AuxXxilium/linux_dsm_epyc7002
1
0
Fork 0
mirror of https://github.com/AuxXxilium/linux_dsm_epyc7002.git synced 2024-12-13 20:46:47 +07:00
Code Issues Actions Packages Projects Releases Wiki Activity
00e907127e
linux_dsm_epyc7002/net/rxrpc/call_accept.c

682 lines
17 KiB
C
Raw Normal View History

[AF_RXRPC]: Provide secure RxRPC sockets for use by userspace and kernel both Provide AF_RXRPC sockets that can be used to talk to AFS servers, or serve answers to AFS clients. KerberosIV security is fully supported. The patches and some example test programs can be found in: http://people.redhat.com/~dhowells/rxrpc/ This will eventually replace the old implementation of kernel-only RxRPC currently resident in net/rxrpc/. Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-27 05:48:28 +07:00
/* incoming call handling
*
* Copyright (C) 2007 Red Hat, Inc. All Rights Reserved.
* Written by David Howells (dhowells@redhat.com)
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version
* 2 of the License, or (at your option) any later version.
*/
rxrpc: Use pr_<level> and pr_fmt, reduce object size a few KB Use the more common kernel logging style and reduce object size. The logging message prefix changes from a mixture of "RxRPC:" and "RXRPC:" to "af_rxrpc: ". $ size net/rxrpc/built-in.o* text data bss dec hex filename 64172 1972 8304 74448 122d0 net/rxrpc/built-in.o.new 67512 1972 8304 77788 12fdc net/rxrpc/built-in.o.old Miscellanea: o Consolidate the ASSERT macros to use a single pr_err call with decimal and hexadecimal output and a stringified #OP argument Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-06-03 02:08:52 +07:00
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
[AF_RXRPC]: Provide secure RxRPC sockets for use by userspace and kernel both Provide AF_RXRPC sockets that can be used to talk to AFS servers, or serve answers to AFS clients. KerberosIV security is fully supported. The patches and some example test programs can be found in: http://people.redhat.com/~dhowells/rxrpc/ This will eventually replace the old implementation of kernel-only RxRPC currently resident in net/rxrpc/. Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-27 05:48:28 +07:00
#include <linux/module.h>
#include <linux/net.h>
#include <linux/skbuff.h>
#include <linux/errqueue.h>
#include <linux/udp.h>
#include <linux/in.h>
#include <linux/in6.h>
#include <linux/icmp.h>
include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h percpu.h is included by sched.h and module.h and thus ends up being included when building most .c files. percpu.h includes slab.h which in turn includes gfp.h making everything defined by the two files universally available and complicating inclusion dependencies. percpu.h -> slab.h dependency is about to be removed. Prepare for this change by updating users of gfp and slab facilities include those headers directly instead of assuming availability. As this conversion needs to touch large number of source files, the following script is used as the basis of conversion. http://userweb.kernel.org/~tj/misc/slabh-sweep.py The script does the followings. * Scan files for gfp and slab usages and update includes such that only the necessary includes are there. ie. if only gfp is used, gfp.h, if slab is used, slab.h. * When the script inserts a new include, it looks at the include blocks and try to put the new include such that its order conforms to its surrounding. It's put in the include block which contains core kernel includes, in the same order that the rest are ordered - alphabetical, Christmas tree, rev-Xmas-tree or at the end if there doesn't seem to be any matching order. * If the script can't find a place to put a new include (mostly because the file doesn't have fitting include block), it prints out an error message indicating which .h file needs to be added to the file. The conversion was done in the following steps. 1. The initial automatic conversion of all .c files updated slightly over 4000 files, deleting around 700 includes and adding ~480 gfp.h and ~3000 slab.h inclusions. The script emitted errors for ~400 files. 2. Each error was manually checked. Some didn't need the inclusion, some needed manual addition while adding it to implementation .h or embedding .c file was more appropriate for others. This step added inclusions to around 150 files. 3. The script was run again and the output was compared to the edits from #2 to make sure no file was left behind. 4. Several build tests were done and a couple of problems were fixed. e.g. lib/decompress_*.c used malloc/free() wrappers around slab APIs requiring slab.h to be added manually. 5. The script was run on all .h files but without automatically editing them as sprinkling gfp.h and slab.h inclusions around .h files could easily lead to inclusion dependency hell. Most gfp.h inclusion directives were ignored as stuff from gfp.h was usually wildly available and often used in preprocessor macros. Each slab.h inclusion directive was examined and added manually as necessary. 6. percpu.h was updated not to include slab.h. 7. Build test were done on the following configurations and failures were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my distributed build env didn't work with gcov compiles) and a few more options had to be turned off depending on archs to make things build (like ipr on powerpc/64 which failed due to missing writeq). * x86 and x86_64 UP and SMP allmodconfig and a custom test config. * powerpc and powerpc64 SMP allmodconfig * sparc and sparc64 SMP allmodconfig * ia64 SMP allmodconfig * s390 SMP allmodconfig * alpha SMP allmodconfig * um on x86_64 SMP allmodconfig 8. percpu.h modifications were reverted so that it could be applied as a separate patch and serve as bisection point. Given the fact that I had only a couple of failures from tests on step 6, I'm fairly confident about the coverage of this conversion patch. If there is a breakage, it's likely to be something in one of the arch headers which should be easily discoverable easily on most builds of the specific arch. Signed-off-by: Tejun Heo <tj@kernel.org> Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
2010-03-24 15:04:11 +07:00
#include <linux/gfp.h>
rxrpc: Preallocate peers, conns and calls for incoming service requests Make it possible for the data_ready handler called from the UDP transport socket to completely instantiate an rxrpc_call structure and make it immediately live by preallocating all the memory it might need. The idea is to cut out the background thread usage as much as possible. [Note that the preallocated structs are not actually used in this patch - that will be done in a future patch.] If insufficient resources are available in the preallocation buffers, it will be possible to discard the DATA packet in the data_ready handler or schedule a BUSY packet without the need to schedule an attempt at allocation in a background thread. To this end: (1) Preallocate rxrpc_peer, rxrpc_connection and rxrpc_call structs to a maximum number each of the listen backlog size. The backlog size is limited to a maxmimum of 32. Only this many of each can be in the preallocation buffer. (2) For userspace sockets, the preallocation is charged initially by listen() and will be recharged by accepting or rejecting pending new incoming calls. (3) For kernel services {,re,dis}charging of the preallocation buffers is handled manually. Two notifier callbacks have to be provided before kernel_listen() is invoked: (a) An indication that a new call has been instantiated. This can be used to trigger background recharging. (b) An indication that a call is being discarded. This is used when the socket is being released. A function, rxrpc_kernel_charge_accept() is called by the kernel service to preallocate a single call. It should be passed the user ID to be used for that call and a callback to associate the rxrpc call with the kernel service's side of the ID. (4) Discard the preallocation when the socket is closed. (5) Temporarily bump the refcount on the call allocated in rxrpc_incoming_call() so that rxrpc_release_call() can ditch the preallocation ref on service calls unconditionally. This will no longer be necessary once the preallocation is used. Note that this does not yet control the number of active service calls on a client - that will come in a later patch. A future development would be to provide a setsockopt() call that allows a userspace server to manually charge the preallocation buffer. This would allow user call IDs to be provided in advance and the awkward manual accept stage to be bypassed. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-08 17:10:12 +07:00
#include <linux/circ_buf.h>
[AF_RXRPC]: Provide secure RxRPC sockets for use by userspace and kernel both Provide AF_RXRPC sockets that can be used to talk to AFS servers, or serve answers to AFS clients. KerberosIV security is fully supported. The patches and some example test programs can be found in: http://people.redhat.com/~dhowells/rxrpc/ This will eventually replace the old implementation of kernel-only RxRPC currently resident in net/rxrpc/. Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-27 05:48:28 +07:00
#include <net/sock.h>
#include <net/af_rxrpc.h>
#include <net/ip.h>
#include "ar-internal.h"
rxrpc: Preallocate peers, conns and calls for incoming service requests Make it possible for the data_ready handler called from the UDP transport socket to completely instantiate an rxrpc_call structure and make it immediately live by preallocating all the memory it might need. The idea is to cut out the background thread usage as much as possible. [Note that the preallocated structs are not actually used in this patch - that will be done in a future patch.] If insufficient resources are available in the preallocation buffers, it will be possible to discard the DATA packet in the data_ready handler or schedule a BUSY packet without the need to schedule an attempt at allocation in a background thread. To this end: (1) Preallocate rxrpc_peer, rxrpc_connection and rxrpc_call structs to a maximum number each of the listen backlog size. The backlog size is limited to a maxmimum of 32. Only this many of each can be in the preallocation buffer. (2) For userspace sockets, the preallocation is charged initially by listen() and will be recharged by accepting or rejecting pending new incoming calls. (3) For kernel services {,re,dis}charging of the preallocation buffers is handled manually. Two notifier callbacks have to be provided before kernel_listen() is invoked: (a) An indication that a new call has been instantiated. This can be used to trigger background recharging. (b) An indication that a call is being discarded. This is used when the socket is being released. A function, rxrpc_kernel_charge_accept() is called by the kernel service to preallocate a single call. It should be passed the user ID to be used for that call and a callback to associate the rxrpc call with the kernel service's side of the ID. (4) Discard the preallocation when the socket is closed. (5) Temporarily bump the refcount on the call allocated in rxrpc_incoming_call() so that rxrpc_release_call() can ditch the preallocation ref on service calls unconditionally. This will no longer be necessary once the preallocation is used. Note that this does not yet control the number of active service calls on a client - that will come in a later patch. A future development would be to provide a setsockopt() call that allows a userspace server to manually charge the preallocation buffer. This would allow user call IDs to be provided in advance and the awkward manual accept stage to be bypassed. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-08 17:10:12 +07:00
/*
* Preallocate a single service call, connection and peer and, if possible,
* give them a user ID and attach the user's side of the ID to them.
*/
static int rxrpc_service_prealloc_one(struct rxrpc_sock *rx,
struct rxrpc_backlog *b,
rxrpc_notify_rx_t notify_rx,
rxrpc_user_attach_call_t user_attach_call,
unsigned long user_call_ID, gfp_t gfp)
{
const void *here = __builtin_return_address(0);
struct rxrpc_call *call;
int max, tmp;
unsigned int size = RXRPC_BACKLOG_MAX;
unsigned int head, tail, call_head, call_tail;
max = rx->sk.sk_max_ack_backlog;
tmp = rx->sk.sk_ack_backlog;
if (tmp >= max) {
_leave(" = -ENOBUFS [full %u]", max);
return -ENOBUFS;
}
max -= tmp;
/* We don't need more conns and peers than we have calls, but on the
* other hand, we shouldn't ever use more peers than conns or conns
* than calls.
*/
call_head = b->call_backlog_head;
call_tail = READ_ONCE(b->call_backlog_tail);
tmp = CIRC_CNT(call_head, call_tail, size);
if (tmp >= max) {
_leave(" = -ENOBUFS [enough %u]", tmp);
return -ENOBUFS;
}
max = tmp + 1;
head = b->peer_backlog_head;
tail = READ_ONCE(b->peer_backlog_tail);
if (CIRC_CNT(head, tail, size) < max) {
struct rxrpc_peer *peer = rxrpc_alloc_peer(rx->local, gfp);
if (!peer)
return -ENOMEM;
b->peer_backlog[head] = peer;
smp_store_release(&b->peer_backlog_head,
(head + 1) & (size - 1));
}
head = b->conn_backlog_head;
tail = READ_ONCE(b->conn_backlog_tail);
if (CIRC_CNT(head, tail, size) < max) {
struct rxrpc_connection *conn;
conn = rxrpc_prealloc_service_connection(gfp);
if (!conn)
return -ENOMEM;
b->conn_backlog[head] = conn;
smp_store_release(&b->conn_backlog_head,
(head + 1) & (size - 1));
}
/* Now it gets complicated, because calls get registered with the
* socket here, particularly if a user ID is preassigned by the user.
*/
call = rxrpc_alloc_call(gfp);
if (!call)
return -ENOMEM;
call->flags |= (1 << RXRPC_CALL_IS_SERVICE);
call->state = RXRPC_CALL_SERVER_PREALLOC;
trace_rxrpc_call(call, rxrpc_call_new_service,
atomic_read(&call->usage),
here, (const void *)user_call_ID);
write_lock(&rx->call_lock);
if (user_attach_call) {
struct rxrpc_call *xcall;
struct rb_node *parent, **pp;
/* Check the user ID isn't already in use */
pp = &rx->calls.rb_node;
parent = NULL;
while (*pp) {
parent = *pp;
xcall = rb_entry(parent, struct rxrpc_call, sock_node);
if (user_call_ID < call->user_call_ID)
pp = &(*pp)->rb_left;
else if (user_call_ID > call->user_call_ID)
pp = &(*pp)->rb_right;
else
goto id_in_use;
}
call->user_call_ID = user_call_ID;
call->notify_rx = notify_rx;
rxrpc_get_call(call, rxrpc_call_got);
user_attach_call(call, user_call_ID);
rxrpc_get_call(call, rxrpc_call_got_userid);
rb_link_node(&call->sock_node, parent, pp);
rb_insert_color(&call->sock_node, &rx->calls);
set_bit(RXRPC_CALL_HAS_USERID, &call->flags);
}
write_unlock(&rx->call_lock);
write_lock(&rxrpc_call_lock);
list_add_tail(&call->link, &rxrpc_calls);
write_unlock(&rxrpc_call_lock);
b->call_backlog[call_head] = call;
smp_store_release(&b->call_backlog_head, (call_head + 1) & (size - 1));
_leave(" = 0 [%d -> %lx]", call->debug_id, user_call_ID);
return 0;
id_in_use:
write_unlock(&rx->call_lock);
rxrpc_cleanup_call(call);
_leave(" = -EBADSLT");
return -EBADSLT;
}
/*
* Preallocate sufficient service connections, calls and peers to cover the
* entire backlog of a socket. When a new call comes in, if we don't have
* sufficient of each available, the call gets rejected as busy or ignored.
*
* The backlog is replenished when a connection is accepted or rejected.
*/
int rxrpc_service_prealloc(struct rxrpc_sock *rx, gfp_t gfp)
{
struct rxrpc_backlog *b = rx->backlog;
if (!b) {
b = kzalloc(sizeof(struct rxrpc_backlog), gfp);
if (!b)
return -ENOMEM;
rx->backlog = b;
}
if (rx->discard_new_call)
return 0;
while (rxrpc_service_prealloc_one(rx, b, NULL, NULL, 0, gfp) == 0)
;
return 0;
}
/*
* Discard the preallocation on a service.
*/
void rxrpc_discard_prealloc(struct rxrpc_sock *rx)
{
struct rxrpc_backlog *b = rx->backlog;
unsigned int size = RXRPC_BACKLOG_MAX, head, tail;
if (!b)
return;
rx->backlog = NULL;
head = b->peer_backlog_head;
tail = b->peer_backlog_tail;
while (CIRC_CNT(head, tail, size) > 0) {
struct rxrpc_peer *peer = b->peer_backlog[tail];
kfree(peer);
tail = (tail + 1) & (size - 1);
}
head = b->conn_backlog_head;
tail = b->conn_backlog_tail;
while (CIRC_CNT(head, tail, size) > 0) {
struct rxrpc_connection *conn = b->conn_backlog[tail];
write_lock(&rxrpc_connection_lock);
list_del(&conn->link);
list_del(&conn->proc_link);
write_unlock(&rxrpc_connection_lock);
kfree(conn);
tail = (tail + 1) & (size - 1);
}
head = b->call_backlog_head;
tail = b->call_backlog_tail;
while (CIRC_CNT(head, tail, size) > 0) {
struct rxrpc_call *call = b->call_backlog[tail];
if (rx->discard_new_call) {
_debug("discard %lx", call->user_call_ID);
rx->discard_new_call(call, call->user_call_ID);
}
rxrpc_call_completed(call);
rxrpc_release_call(rx, call);
rxrpc_put_call(call, rxrpc_call_put);
tail = (tail + 1) & (size - 1);
}
kfree(b);
}
[AF_RXRPC]: Provide secure RxRPC sockets for use by userspace and kernel both Provide AF_RXRPC sockets that can be used to talk to AFS servers, or serve answers to AFS clients. KerberosIV security is fully supported. The patches and some example test programs can be found in: http://people.redhat.com/~dhowells/rxrpc/ This will eventually replace the old implementation of kernel-only RxRPC currently resident in net/rxrpc/. Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-27 05:48:28 +07:00
/*
* generate a connection-level abort
*/
static int rxrpc_busy(struct rxrpc_local *local, struct sockaddr_rxrpc *srx,
rxrpc: Keep the skb private record of the Rx header in host byte order Currently, a copy of the Rx packet header is copied into the the sk_buff private data so that we can advance the pointer into the buffer, potentially discarding the original. At the moment, this copy is held in network byte order, but this means we're doing a lot of unnecessary translations. The reasons it was done this way are that we need the values in network byte order occasionally and we can use the copy, slightly modified, as part of an iov array when sending an ack or an abort packet. However, it seems more reasonable on review that it would be better kept in host byte order and that we make up a new header when we want to send another packet. To this end, rename the original header struct to rxrpc_wire_header (with BE fields) and institute a variant called rxrpc_host_header that has host order fields. Change the struct in the sk_buff private data into an rxrpc_host_header and translate the values when filling it in. This further allows us to keep values kept in various structures in host byte order rather than network byte order and allows removal of some fields that are byteswapped duplicates. Signed-off-by: David Howells <dhowells@redhat.com>
2016-03-04 22:53:46 +07:00
struct rxrpc_wire_header *whdr)
[AF_RXRPC]: Provide secure RxRPC sockets for use by userspace and kernel both Provide AF_RXRPC sockets that can be used to talk to AFS servers, or serve answers to AFS clients. KerberosIV security is fully supported. The patches and some example test programs can be found in: http://people.redhat.com/~dhowells/rxrpc/ This will eventually replace the old implementation of kernel-only RxRPC currently resident in net/rxrpc/. Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-27 05:48:28 +07:00
{
struct msghdr msg;
struct kvec iov[1];
size_t len;
int ret;
_enter("%d,,", local->debug_id);
rxrpc: Keep the skb private record of the Rx header in host byte order Currently, a copy of the Rx packet header is copied into the the sk_buff private data so that we can advance the pointer into the buffer, potentially discarding the original. At the moment, this copy is held in network byte order, but this means we're doing a lot of unnecessary translations. The reasons it was done this way are that we need the values in network byte order occasionally and we can use the copy, slightly modified, as part of an iov array when sending an ack or an abort packet. However, it seems more reasonable on review that it would be better kept in host byte order and that we make up a new header when we want to send another packet. To this end, rename the original header struct to rxrpc_wire_header (with BE fields) and institute a variant called rxrpc_host_header that has host order fields. Change the struct in the sk_buff private data into an rxrpc_host_header and translate the values when filling it in. This further allows us to keep values kept in various structures in host byte order rather than network byte order and allows removal of some fields that are byteswapped duplicates. Signed-off-by: David Howells <dhowells@redhat.com>
2016-03-04 22:53:46 +07:00
whdr->type = RXRPC_PACKET_TYPE_BUSY;
whdr->serial = htonl(1);
[AF_RXRPC]: Provide secure RxRPC sockets for use by userspace and kernel both Provide AF_RXRPC sockets that can be used to talk to AFS servers, or serve answers to AFS clients. KerberosIV security is fully supported. The patches and some example test programs can be found in: http://people.redhat.com/~dhowells/rxrpc/ This will eventually replace the old implementation of kernel-only RxRPC currently resident in net/rxrpc/. Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-27 05:48:28 +07:00
msg.msg_name = &srx->transport.sin;
msg.msg_namelen = sizeof(srx->transport.sin);
msg.msg_control = NULL;
msg.msg_controllen = 0;
msg.msg_flags = 0;
rxrpc: Keep the skb private record of the Rx header in host byte order Currently, a copy of the Rx packet header is copied into the the sk_buff private data so that we can advance the pointer into the buffer, potentially discarding the original. At the moment, this copy is held in network byte order, but this means we're doing a lot of unnecessary translations. The reasons it was done this way are that we need the values in network byte order occasionally and we can use the copy, slightly modified, as part of an iov array when sending an ack or an abort packet. However, it seems more reasonable on review that it would be better kept in host byte order and that we make up a new header when we want to send another packet. To this end, rename the original header struct to rxrpc_wire_header (with BE fields) and institute a variant called rxrpc_host_header that has host order fields. Change the struct in the sk_buff private data into an rxrpc_host_header and translate the values when filling it in. This further allows us to keep values kept in various structures in host byte order rather than network byte order and allows removal of some fields that are byteswapped duplicates. Signed-off-by: David Howells <dhowells@redhat.com>
2016-03-04 22:53:46 +07:00
iov[0].iov_base = whdr;
iov[0].iov_len = sizeof(*whdr);
[AF_RXRPC]: Provide secure RxRPC sockets for use by userspace and kernel both Provide AF_RXRPC sockets that can be used to talk to AFS servers, or serve answers to AFS clients. KerberosIV security is fully supported. The patches and some example test programs can be found in: http://people.redhat.com/~dhowells/rxrpc/ This will eventually replace the old implementation of kernel-only RxRPC currently resident in net/rxrpc/. Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-27 05:48:28 +07:00
len = iov[0].iov_len;
rxrpc: Keep the skb private record of the Rx header in host byte order Currently, a copy of the Rx packet header is copied into the the sk_buff private data so that we can advance the pointer into the buffer, potentially discarding the original. At the moment, this copy is held in network byte order, but this means we're doing a lot of unnecessary translations. The reasons it was done this way are that we need the values in network byte order occasionally and we can use the copy, slightly modified, as part of an iov array when sending an ack or an abort packet. However, it seems more reasonable on review that it would be better kept in host byte order and that we make up a new header when we want to send another packet. To this end, rename the original header struct to rxrpc_wire_header (with BE fields) and institute a variant called rxrpc_host_header that has host order fields. Change the struct in the sk_buff private data into an rxrpc_host_header and translate the values when filling it in. This further allows us to keep values kept in various structures in host byte order rather than network byte order and allows removal of some fields that are byteswapped duplicates. Signed-off-by: David Howells <dhowells@redhat.com>
2016-03-04 22:53:46 +07:00
_proto("Tx BUSY %%1");
[AF_RXRPC]: Provide secure RxRPC sockets for use by userspace and kernel both Provide AF_RXRPC sockets that can be used to talk to AFS servers, or serve answers to AFS clients. KerberosIV security is fully supported. The patches and some example test programs can be found in: http://people.redhat.com/~dhowells/rxrpc/ This will eventually replace the old implementation of kernel-only RxRPC currently resident in net/rxrpc/. Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-27 05:48:28 +07:00
ret = kernel_sendmsg(local->socket, &msg, iov, 1, len);
if (ret < 0) {
_leave(" = -EAGAIN [sendmsg failed: %d]", ret);
return -EAGAIN;
}
_leave(" = 0");
return 0;
}
/*
* accept an incoming call that needs peer, transport and/or connection setting
* up
*/
static int rxrpc_accept_incoming_call(struct rxrpc_local *local,
struct rxrpc_sock *rx,
struct sk_buff *skb,
struct sockaddr_rxrpc *srx)
{
struct rxrpc_connection *conn;
struct rxrpc_skb_priv *sp, *nsp;
struct rxrpc_call *call;
struct sk_buff *notification;
int ret;
_enter("");
sp = rxrpc_skb(skb);
/* get a notification message to send to the server app */
notification = alloc_skb(0, GFP_NOFS);
rxrpc: Check allocation failure. alloc_skb() can return NULL. Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-03-22 20:50:19 +07:00
if (!notification) {
_debug("no memory");
ret = -ENOMEM;
goto error_nofree;
}
[AF_RXRPC]: Provide secure RxRPC sockets for use by userspace and kernel both Provide AF_RXRPC sockets that can be used to talk to AFS servers, or serve answers to AFS clients. KerberosIV security is fully supported. The patches and some example test programs can be found in: http://people.redhat.com/~dhowells/rxrpc/ This will eventually replace the old implementation of kernel-only RxRPC currently resident in net/rxrpc/. Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-27 05:48:28 +07:00
rxrpc_new_skb(notification);
notification->mark = RXRPC_SKB_MARK_NEW_CALL;
rxrpc: Move peer lookup from call-accept to new-incoming-conn Move the lookup of a peer from a call that's being accepted into the function that creates a new incoming connection. This will allow us to avoid incrementing the peer's usage count in some cases in future. Note that I haven't bother to integrate rxrpc_get_addr_from_skb() with rxrpc_extract_addr_from_skb() as I'm going to delete the former in the very near future. Signed-off-by: David Howells <dhowells@redhat.com>
2016-06-29 20:40:39 +07:00
conn = rxrpc_incoming_connection(local, srx, skb);
[AF_RXRPC]: Provide secure RxRPC sockets for use by userspace and kernel both Provide AF_RXRPC sockets that can be used to talk to AFS servers, or serve answers to AFS clients. KerberosIV security is fully supported. The patches and some example test programs can be found in: http://people.redhat.com/~dhowells/rxrpc/ This will eventually replace the old implementation of kernel-only RxRPC currently resident in net/rxrpc/. Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-27 05:48:28 +07:00
if (IS_ERR(conn)) {
_debug("no conn");
ret = PTR_ERR(conn);
goto error;
}
rxrpc: Pass sk_buff * rather than rxrpc_host_header * to functions Pass a pointer to struct sk_buff rather than struct rxrpc_host_header to functions so that they can in the future get at transport protocol parameters rather than just RxRPC parameters. Signed-off-by: David Howells <dhowells@redhat.com>
2016-06-16 19:31:07 +07:00
call = rxrpc_incoming_call(rx, conn, skb);
[AF_RXRPC]: Provide secure RxRPC sockets for use by userspace and kernel both Provide AF_RXRPC sockets that can be used to talk to AFS servers, or serve answers to AFS clients. KerberosIV security is fully supported. The patches and some example test programs can be found in: http://people.redhat.com/~dhowells/rxrpc/ This will eventually replace the old implementation of kernel-only RxRPC currently resident in net/rxrpc/. Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-27 05:48:28 +07:00
rxrpc_put_connection(conn);
if (IS_ERR(call)) {
_debug("no call");
ret = PTR_ERR(call);
goto error;
}
/* attach the call to the socket */
read_lock_bh(&local->services_lock);
if (rx->sk.sk_state == RXRPC_CLOSE)
goto invalid_service;
write_lock(&rx->call_lock);
if (!test_and_set_bit(RXRPC_CALL_INIT_ACCEPT, &call->flags)) {
rxrpc: Improve the call tracking tracepoint Improve the call tracking tracepoint by showing more differentiation between some of the put and get events, including: (1) Getting and putting refs for the socket call user ID tree. (2) Getting and putting refs for queueing and failing to queue the call processor work item. Note that these aren't necessarily used in this patch, but will be taken advantage of in future patches. An enum is added for the event subtype numbers rather than coding them directly as decimal numbers and a table of 3-letter strings is provided rather than a sequence of ?: operators. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-07 20:34:21 +07:00
rxrpc_get_call(call, rxrpc_call_got);
[AF_RXRPC]: Provide secure RxRPC sockets for use by userspace and kernel both Provide AF_RXRPC sockets that can be used to talk to AFS servers, or serve answers to AFS clients. KerberosIV security is fully supported. The patches and some example test programs can be found in: http://people.redhat.com/~dhowells/rxrpc/ This will eventually replace the old implementation of kernel-only RxRPC currently resident in net/rxrpc/. Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-27 05:48:28 +07:00
spin_lock(&call->conn->state_lock);
if (sp->hdr.securityIndex > 0 &&
rxrpc: Turn connection #defines into enums and put outside struct def Turn the connection event and state #define lists into enums and move outside of the struct definition. Whilst we're at it, change _SERVER to _SERVICE in those identifiers and add EV_ into the event name to distinguish them from flags and states. Also add a symbol indicating the number of states and use that in the state text array. Signed-off-by: David Howells <dhowells@redhat.com>
2016-06-27 16:32:02 +07:00
call->conn->state == RXRPC_CONN_SERVICE_UNSECURED) {
[AF_RXRPC]: Provide secure RxRPC sockets for use by userspace and kernel both Provide AF_RXRPC sockets that can be used to talk to AFS servers, or serve answers to AFS clients. KerberosIV security is fully supported. The patches and some example test programs can be found in: http://people.redhat.com/~dhowells/rxrpc/ This will eventually replace the old implementation of kernel-only RxRPC currently resident in net/rxrpc/. Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-27 05:48:28 +07:00
_debug("await conn sec");
list_add_tail(&call->accept_link, &rx->secureq);
rxrpc: Turn connection #defines into enums and put outside struct def Turn the connection event and state #define lists into enums and move outside of the struct definition. Whilst we're at it, change _SERVER to _SERVICE in those identifiers and add EV_ into the event name to distinguish them from flags and states. Also add a symbol indicating the number of states and use that in the state text array. Signed-off-by: David Howells <dhowells@redhat.com>
2016-06-27 16:32:02 +07:00
call->conn->state = RXRPC_CONN_SERVICE_CHALLENGING;
set_bit(RXRPC_CONN_EV_CHALLENGE, &call->conn->events);
[AF_RXRPC]: Add an interface to the AF_RXRPC module for the AFS filesystem to use Add an interface to the AF_RXRPC module so that the AFS filesystem module can more easily make use of the services available. AFS still opens a socket but then uses the action functions in lieu of sendmsg() and registers an intercept functions to grab messages before they're queued on the socket Rx queue. This permits AFS (or whatever) to: (1) Avoid the overhead of using the recvmsg() call. (2) Use different keys directly on individual client calls on one socket rather than having to open a whole slew of sockets, one for each key it might want to use. (3) Avoid calling request_key() at the point of issue of a call or opening of a socket. This is done instead by AFS at the point of open(), unlink() or other VFS operation and the key handed through. (4) Request the use of something other than GFP_KERNEL to allocate memory. Furthermore: (*) The socket buffer markings used by RxRPC are made available for AFS so that it can interpret the cooked RxRPC messages itself. (*) rxgen (un)marshalling abort codes are made available. The following documentation for the kernel interface is added to Documentation/networking/rxrpc.txt: ========================= AF_RXRPC KERNEL INTERFACE ========================= The AF_RXRPC module also provides an interface for use by in-kernel utilities such as the AFS filesystem. This permits such a utility to: (1) Use different keys directly on individual client calls on one socket rather than having to open a whole slew of sockets, one for each key it might want to use. (2) Avoid having RxRPC call request_key() at the point of issue of a call or opening of a socket. Instead the utility is responsible for requesting a key at the appropriate point. AFS, for instance, would do this during VFS operations such as open() or unlink(). The key is then handed through when the call is initiated. (3) Request the use of something other than GFP_KERNEL to allocate memory. (4) Avoid the overhead of using the recvmsg() call. RxRPC messages can be intercepted before they get put into the socket Rx queue and the socket buffers manipulated directly. To use the RxRPC facility, a kernel utility must still open an AF_RXRPC socket, bind an addess as appropriate and listen if it's to be a server socket, but then it passes this to the kernel interface functions. The kernel interface functions are as follows: (*) Begin a new client call. struct rxrpc_call * rxrpc_kernel_begin_call(struct socket *sock, struct sockaddr_rxrpc *srx, struct key *key, unsigned long user_call_ID, gfp_t gfp); This allocates the infrastructure to make a new RxRPC call and assigns call and connection numbers. The call will be made on the UDP port that the socket is bound to. The call will go to the destination address of a connected client socket unless an alternative is supplied (srx is non-NULL). If a key is supplied then this will be used to secure the call instead of the key bound to the socket with the RXRPC_SECURITY_KEY sockopt. Calls secured in this way will still share connections if at all possible. The user_call_ID is equivalent to that supplied to sendmsg() in the control data buffer. It is entirely feasible to use this to point to a kernel data structure. If this function is successful, an opaque reference to the RxRPC call is returned. The caller now holds a reference on this and it must be properly ended. (*) End a client call. void rxrpc_kernel_end_call(struct rxrpc_call *call); This is used to end a previously begun call. The user_call_ID is expunged from AF_RXRPC's knowledge and will not be seen again in association with the specified call. (*) Send data through a call. int rxrpc_kernel_send_data(struct rxrpc_call *call, struct msghdr *msg, size_t len); This is used to supply either the request part of a client call or the reply part of a server call. msg.msg_iovlen and msg.msg_iov specify the data buffers to be used. msg_iov may not be NULL and must point exclusively to in-kernel virtual addresses. msg.msg_flags may be given MSG_MORE if there will be subsequent data sends for this call. The msg must not specify a destination address, control data or any flags other than MSG_MORE. len is the total amount of data to transmit. (*) Abort a call. void rxrpc_kernel_abort_call(struct rxrpc_call *call, u32 abort_code); This is used to abort a call if it's still in an abortable state. The abort code specified will be placed in the ABORT message sent. (*) Intercept received RxRPC messages. typedef void (*rxrpc_interceptor_t)(struct sock *sk, unsigned long user_call_ID, struct sk_buff *skb); void rxrpc_kernel_intercept_rx_messages(struct socket *sock, rxrpc_interceptor_t interceptor); This installs an interceptor function on the specified AF_RXRPC socket. All messages that would otherwise wind up in the socket's Rx queue are then diverted to this function. Note that care must be taken to process the messages in the right order to maintain DATA message sequentiality. The interceptor function itself is provided with the address of the socket and handling the incoming message, the ID assigned by the kernel utility to the call and the socket buffer containing the message. The skb->mark field indicates the type of message: MARK MEANING =============================== ======================================= RXRPC_SKB_MARK_DATA Data message RXRPC_SKB_MARK_FINAL_ACK Final ACK received for an incoming call RXRPC_SKB_MARK_BUSY Client call rejected as server busy RXRPC_SKB_MARK_REMOTE_ABORT Call aborted by peer RXRPC_SKB_MARK_NET_ERROR Network error detected RXRPC_SKB_MARK_LOCAL_ERROR Local error encountered RXRPC_SKB_MARK_NEW_CALL New incoming call awaiting acceptance The remote abort message can be probed with rxrpc_kernel_get_abort_code(). The two error messages can be probed with rxrpc_kernel_get_error_number(). A new call can be accepted with rxrpc_kernel_accept_call(). Data messages can have their contents extracted with the usual bunch of socket buffer manipulation functions. A data message can be determined to be the last one in a sequence with rxrpc_kernel_is_data_last(). When a data message has been used up, rxrpc_kernel_data_delivered() should be called on it.. Non-data messages should be handled to rxrpc_kernel_free_skb() to dispose of. It is possible to get extra refs on all types of message for later freeing, but this may pin the state of a call until the message is finally freed. (*) Accept an incoming call. struct rxrpc_call * rxrpc_kernel_accept_call(struct socket *sock, unsigned long user_call_ID); This is used to accept an incoming call and to assign it a call ID. This function is similar to rxrpc_kernel_begin_call() and calls accepted must be ended in the same way. If this function is successful, an opaque reference to the RxRPC call is returned. The caller now holds a reference on this and it must be properly ended. (*) Reject an incoming call. int rxrpc_kernel_reject_call(struct socket *sock); This is used to reject the first incoming call on the socket's queue with a BUSY message. -ENODATA is returned if there were no incoming calls. Other errors may be returned if the call had been aborted (-ECONNABORTED) or had timed out (-ETIME). (*) Record the delivery of a data message and free it. void rxrpc_kernel_data_delivered(struct sk_buff *skb); This is used to record a data message as having been delivered and to update the ACK state for the call. The socket buffer will be freed. (*) Free a message. void rxrpc_kernel_free_skb(struct sk_buff *skb); This is used to free a non-DATA socket buffer intercepted from an AF_RXRPC socket. (*) Determine if a data message is the last one on a call. bool rxrpc_kernel_is_data_last(struct sk_buff *skb); This is used to determine if a socket buffer holds the last data message to be received for a call (true will be returned if it does, false if not). The data message will be part of the reply on a client call and the request on an incoming call. In the latter case there will be more messages, but in the former case there will not. (*) Get the abort code from an abort message. u32 rxrpc_kernel_get_abort_code(struct sk_buff *skb); This is used to extract the abort code from a remote abort message. (*) Get the error number from a local or network error message. int rxrpc_kernel_get_error_number(struct sk_buff *skb); This is used to extract the error number from a message indicating either a local error occurred or a network error occurred. Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-27 05:50:17 +07:00
rxrpc_queue_conn(call->conn);
[AF_RXRPC]: Provide secure RxRPC sockets for use by userspace and kernel both Provide AF_RXRPC sockets that can be used to talk to AFS servers, or serve answers to AFS clients. KerberosIV security is fully supported. The patches and some example test programs can be found in: http://people.redhat.com/~dhowells/rxrpc/ This will eventually replace the old implementation of kernel-only RxRPC currently resident in net/rxrpc/. Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-27 05:48:28 +07:00
} else {
_debug("conn ready");
call->state = RXRPC_CALL_SERVER_ACCEPTING;
list_add_tail(&call->accept_link, &rx->acceptq);
rxrpc: Trace rxrpc_call usage Add a trace event for debuging rxrpc_call struct usage. Signed-off-by: David Howells <dhowells@redhat.com>
2016-08-30 15:49:29 +07:00
rxrpc_get_call_for_skb(call, notification);
[AF_RXRPC]: Provide secure RxRPC sockets for use by userspace and kernel both Provide AF_RXRPC sockets that can be used to talk to AFS servers, or serve answers to AFS clients. KerberosIV security is fully supported. The patches and some example test programs can be found in: http://people.redhat.com/~dhowells/rxrpc/ This will eventually replace the old implementation of kernel-only RxRPC currently resident in net/rxrpc/. Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-27 05:48:28 +07:00
nsp = rxrpc_skb(notification);
nsp->call = call;
ASSERTCMP(atomic_read(&call->usage), >=, 3);
_debug("notify");
spin_lock(&call->lock);
ret = rxrpc_queue_rcv_skb(call, notification, true,
false);
spin_unlock(&call->lock);
notification = NULL;
net/rxrpc: Use BUG_ON if (...) BUG(); should be replaced with BUG_ON(...) when the test has no side-effects to allow a definition of BUG_ON that drops the code completely. The semantic patch that makes this change is as follows: (http://www.emn.fr/x-info/coccinelle/) // <smpl> @ disable unlikely @ expression E,f; @@ ( if (<... f(...) ...>) { BUG(); } | - if (unlikely(E)) { BUG(); } + BUG_ON(E); ) @@ expression E,f; @@ ( if (<... f(...) ...>) { BUG(); } | - if (E) { BUG(); } + BUG_ON(E); ) // </smpl> Signed-off-by: Julia Lawall <julia@diku.dk> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-02-18 09:42:03 +07:00
BUG_ON(ret < 0);
[AF_RXRPC]: Provide secure RxRPC sockets for use by userspace and kernel both Provide AF_RXRPC sockets that can be used to talk to AFS servers, or serve answers to AFS clients. KerberosIV security is fully supported. The patches and some example test programs can be found in: http://people.redhat.com/~dhowells/rxrpc/ This will eventually replace the old implementation of kernel-only RxRPC currently resident in net/rxrpc/. Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-27 05:48:28 +07:00
}
spin_unlock(&call->conn->state_lock);
_debug("queued");
}
write_unlock(&rx->call_lock);
_debug("process");
rxrpc_fast_process_packet(call, skb);
_debug("done");
read_unlock_bh(&local->services_lock);
rxrpc_free_skb(notification);
rxrpc: Improve the call tracking tracepoint Improve the call tracking tracepoint by showing more differentiation between some of the put and get events, including: (1) Getting and putting refs for the socket call user ID tree. (2) Getting and putting refs for queueing and failing to queue the call processor work item. Note that these aren't necessarily used in this patch, but will be taken advantage of in future patches. An enum is added for the event subtype numbers rather than coding them directly as decimal numbers and a table of 3-letter strings is provided rather than a sequence of ?: operators. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-07 20:34:21 +07:00
rxrpc_put_call(call, rxrpc_call_put);
[AF_RXRPC]: Provide secure RxRPC sockets for use by userspace and kernel both Provide AF_RXRPC sockets that can be used to talk to AFS servers, or serve answers to AFS clients. KerberosIV security is fully supported. The patches and some example test programs can be found in: http://people.redhat.com/~dhowells/rxrpc/ This will eventually replace the old implementation of kernel-only RxRPC currently resident in net/rxrpc/. Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-27 05:48:28 +07:00
_leave(" = 0");
return 0;
invalid_service:
_debug("invalid");
read_unlock_bh(&local->services_lock);
rxrpc: Calls shouldn't hold socket refs rxrpc calls shouldn't hold refs on the sock struct. This was done so that the socket wouldn't go away whilst the call was in progress, such that the call could reach the socket's queues. However, we can mark the socket as requiring an RCU release and rely on the RCU read lock. To make this work, we do: (1) rxrpc_release_call() removes the call's call user ID. This is now only called from socket operations and not from the call processor: rxrpc_accept_call() / rxrpc_kernel_accept_call() rxrpc_reject_call() / rxrpc_kernel_reject_call() rxrpc_kernel_end_call() rxrpc_release_calls_on_socket() rxrpc_recvmsg() Though it is also called in the cleanup path of rxrpc_accept_incoming_call() before we assign a user ID. (2) Pass the socket pointer into rxrpc_release_call() rather than getting it from the call so that we can get rid of uninitialised calls. (3) Fix call processor queueing to pass a ref to the work queue and to release that ref at the end of the processor function (or to pass it back to the work queue if we have to requeue). (4) Skip out of the call processor function asap if the call is complete and don't requeue it if the call is complete. (5) Clean up the call immediately that the refcount reaches 0 rather than trying to defer it. Actual deallocation is deferred to RCU, however. (6) Don't hold socket refs for allocated calls. (7) Use the RCU read lock when queueing a message on a socket and treat the call's socket pointer according to RCU rules and check it for NULL. We also need to use the RCU read lock when viewing a call through procfs. (8) Transmit the final ACK/ABORT to a client call in rxrpc_release_call() if this hasn't been done yet so that we can then disconnect the call. Once the call is disconnected, it won't have any access to the connection struct and the UDP socket for the call work processor to be able to send the ACK. Terminal retransmission will be handled by the connection processor. (9) Release all calls immediately on the closing of a socket rather than trying to defer this. Incomplete calls will be aborted. The call refcount model is much simplified. Refs are held on the call by: (1) A socket's user ID tree. (2) A socket's incoming call secureq and acceptq. (3) A kernel service that has a call in progress. (4) A queued call work processor. We have to take care to put any call that we failed to queue. (5) sk_buffs on a socket's receive queue. A future patch will get rid of this. Whilst we're at it, we can do: (1) Get rid of the RXRPC_CALL_EV_RELEASE event. Release is now done entirely from the socket routines and never from the call's processor. (2) Get rid of the RXRPC_CALL_DEAD state. Calls now end in the RXRPC_CALL_COMPLETE state. (3) Get rid of the rxrpc_call::destroyer work item. Calls are now torn down when their refcount reaches 0 and then handed over to RCU for final cleanup. (4) Get rid of the rxrpc_call::deadspan timer. Calls are cleaned up immediately they're finished with and don't hang around. Post-completion retransmission is handled by the connection processor once the call is disconnected. (5) Get rid of the dead call expiry setting as there's no longer a timer to set. (6) rxrpc_destroy_all_calls() can just check that the call list is empty. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-07 15:19:31 +07:00
rxrpc_release_call(rx, call);
rxrpc: Improve the call tracking tracepoint Improve the call tracking tracepoint by showing more differentiation between some of the put and get events, including: (1) Getting and putting refs for the socket call user ID tree. (2) Getting and putting refs for queueing and failing to queue the call processor work item. Note that these aren't necessarily used in this patch, but will be taken advantage of in future patches. An enum is added for the event subtype numbers rather than coding them directly as decimal numbers and a table of 3-letter strings is provided rather than a sequence of ?: operators. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-07 20:34:21 +07:00
rxrpc_put_call(call, rxrpc_call_put);
[AF_RXRPC]: Provide secure RxRPC sockets for use by userspace and kernel both Provide AF_RXRPC sockets that can be used to talk to AFS servers, or serve answers to AFS clients. KerberosIV security is fully supported. The patches and some example test programs can be found in: http://people.redhat.com/~dhowells/rxrpc/ This will eventually replace the old implementation of kernel-only RxRPC currently resident in net/rxrpc/. Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-27 05:48:28 +07:00
ret = -ECONNREFUSED;
error:
rxrpc_free_skb(notification);
rxrpc: Check allocation failure. alloc_skb() can return NULL. Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-03-22 20:50:19 +07:00
error_nofree:
[AF_RXRPC]: Provide secure RxRPC sockets for use by userspace and kernel both Provide AF_RXRPC sockets that can be used to talk to AFS servers, or serve answers to AFS clients. KerberosIV security is fully supported. The patches and some example test programs can be found in: http://people.redhat.com/~dhowells/rxrpc/ This will eventually replace the old implementation of kernel-only RxRPC currently resident in net/rxrpc/. Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-27 05:48:28 +07:00
_leave(" = %d", ret);
return ret;
}
/*
* accept incoming calls that need peer, transport and/or connection setting up
* - the packets we get are all incoming client DATA packets that have seq == 1
*/
rxrpc: Rework local endpoint management Rework the local RxRPC endpoint management. Local endpoint objects are maintained in a flat list as before. This should be okay as there shouldn't be more than one per open AF_RXRPC socket (there can be fewer as local endpoints can be shared if their local service ID is 0 and they share the same local transport parameters). Changes: (1) Local endpoints may now only be shared if they have local service ID 0 (ie. they're not being used for listening). This prevents a scenario where process A is listening of the Cache Manager port and process B contacts a fileserver - which may then attempt to send CM requests back to B. But if A and B are sharing a local endpoint, A will get the CM requests meant for B. (2) We use a mutex to handle lookups and don't provide RCU-only lookups since we only expect to access the list when opening a socket or destroying an endpoint. The local endpoint object is pointed to by the transport socket's sk_user_data for the life of the transport socket - allowing us to refer to it directly from the sk_data_ready and sk_error_report callbacks. (3) atomic_inc_not_zero() now exists and can be used to only share a local endpoint if the last reference hasn't yet gone. (4) We can remove rxrpc_local_lock - a spinlock that had to be taken with BH processing disabled given that we assume sk_user_data won't change under us. (5) The transport socket is shut down before we clear the sk_user_data pointer so that we can be sure that the transport socket's callbacks won't be invoked once the RCU destruction is scheduled. (6) Local endpoints have a work item that handles both destruction and event processing. The means that destruction doesn't then need to wait for event processing. The event queues can then be cleared after the transport socket is shut down. (7) Local endpoints are no longer available for resurrection beyond the life of the sockets that had them open. As soon as their last ref goes, they are scheduled for destruction and may not have their usage count moved from 0. Signed-off-by: David Howells <dhowells@redhat.com>
2016-04-04 20:00:35 +07:00
void rxrpc_accept_incoming_calls(struct rxrpc_local *local)
[AF_RXRPC]: Provide secure RxRPC sockets for use by userspace and kernel both Provide AF_RXRPC sockets that can be used to talk to AFS servers, or serve answers to AFS clients. KerberosIV security is fully supported. The patches and some example test programs can be found in: http://people.redhat.com/~dhowells/rxrpc/ This will eventually replace the old implementation of kernel-only RxRPC currently resident in net/rxrpc/. Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-27 05:48:28 +07:00
{
struct rxrpc_skb_priv *sp;
struct sockaddr_rxrpc srx;
struct rxrpc_sock *rx;
rxrpc: Keep the skb private record of the Rx header in host byte order Currently, a copy of the Rx packet header is copied into the the sk_buff private data so that we can advance the pointer into the buffer, potentially discarding the original. At the moment, this copy is held in network byte order, but this means we're doing a lot of unnecessary translations. The reasons it was done this way are that we need the values in network byte order occasionally and we can use the copy, slightly modified, as part of an iov array when sending an ack or an abort packet. However, it seems more reasonable on review that it would be better kept in host byte order and that we make up a new header when we want to send another packet. To this end, rename the original header struct to rxrpc_wire_header (with BE fields) and institute a variant called rxrpc_host_header that has host order fields. Change the struct in the sk_buff private data into an rxrpc_host_header and translate the values when filling it in. This further allows us to keep values kept in various structures in host byte order rather than network byte order and allows removal of some fields that are byteswapped duplicates. Signed-off-by: David Howells <dhowells@redhat.com>
2016-03-04 22:53:46 +07:00
struct rxrpc_wire_header whdr;
[AF_RXRPC]: Provide secure RxRPC sockets for use by userspace and kernel both Provide AF_RXRPC sockets that can be used to talk to AFS servers, or serve answers to AFS clients. KerberosIV security is fully supported. The patches and some example test programs can be found in: http://people.redhat.com/~dhowells/rxrpc/ This will eventually replace the old implementation of kernel-only RxRPC currently resident in net/rxrpc/. Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-27 05:48:28 +07:00
struct sk_buff *skb;
int ret;
_enter("%d", local->debug_id);
skb = skb_dequeue(&local->accept_queue);
if (!skb) {
_leave("\n");
return;
}
_net("incoming call skb %p", skb);
rxrpc: Use a tracepoint for skb accounting debugging Use a tracepoint to log various skb accounting points to help in debugging refcounting errors. Signed-off-by: David Howells <dhowells@redhat.com>
2016-08-23 21:27:24 +07:00
rxrpc_see_skb(skb);
[AF_RXRPC]: Provide secure RxRPC sockets for use by userspace and kernel both Provide AF_RXRPC sockets that can be used to talk to AFS servers, or serve answers to AFS clients. KerberosIV security is fully supported. The patches and some example test programs can be found in: http://people.redhat.com/~dhowells/rxrpc/ This will eventually replace the old implementation of kernel-only RxRPC currently resident in net/rxrpc/. Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-27 05:48:28 +07:00
sp = rxrpc_skb(skb);
rxrpc: Keep the skb private record of the Rx header in host byte order Currently, a copy of the Rx packet header is copied into the the sk_buff private data so that we can advance the pointer into the buffer, potentially discarding the original. At the moment, this copy is held in network byte order, but this means we're doing a lot of unnecessary translations. The reasons it was done this way are that we need the values in network byte order occasionally and we can use the copy, slightly modified, as part of an iov array when sending an ack or an abort packet. However, it seems more reasonable on review that it would be better kept in host byte order and that we make up a new header when we want to send another packet. To this end, rename the original header struct to rxrpc_wire_header (with BE fields) and institute a variant called rxrpc_host_header that has host order fields. Change the struct in the sk_buff private data into an rxrpc_host_header and translate the values when filling it in. This further allows us to keep values kept in various structures in host byte order rather than network byte order and allows removal of some fields that are byteswapped duplicates. Signed-off-by: David Howells <dhowells@redhat.com>
2016-03-04 22:53:46 +07:00
/* Set up a response packet header in case we need it */
whdr.epoch = htonl(sp->hdr.epoch);
whdr.cid = htonl(sp->hdr.cid);
whdr.callNumber = htonl(sp->hdr.callNumber);
whdr.seq = htonl(sp->hdr.seq);
whdr.serial = 0;
whdr.flags = 0;
whdr.type = 0;
whdr.userStatus = 0;
whdr.securityIndex = sp->hdr.securityIndex;
whdr._rsvd = 0;
whdr.serviceId = htons(sp->hdr.serviceId);
rxrpc: Move peer lookup from call-accept to new-incoming-conn Move the lookup of a peer from a call that's being accepted into the function that creates a new incoming connection. This will allow us to avoid incrementing the peer's usage count in some cases in future. Note that I haven't bother to integrate rxrpc_get_addr_from_skb() with rxrpc_extract_addr_from_skb() as I'm going to delete the former in the very near future. Signed-off-by: David Howells <dhowells@redhat.com>
2016-06-29 20:40:39 +07:00
if (rxrpc_extract_addr_from_skb(&srx, skb) < 0)
goto drop;
[AF_RXRPC]: Provide secure RxRPC sockets for use by userspace and kernel both Provide AF_RXRPC sockets that can be used to talk to AFS servers, or serve answers to AFS clients. KerberosIV security is fully supported. The patches and some example test programs can be found in: http://people.redhat.com/~dhowells/rxrpc/ This will eventually replace the old implementation of kernel-only RxRPC currently resident in net/rxrpc/. Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-27 05:48:28 +07:00
/* get the socket providing the service */
read_lock_bh(&local->services_lock);
rxrpc: Convert rxrpc_local::services to an hlist Convert the rxrpc_local::services list to an hlist so that it can be accessed under RCU conditions more readily. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-08 17:10:11 +07:00
hlist_for_each_entry(rx, &local->services, listen_link) {
rxrpc: Keep the skb private record of the Rx header in host byte order Currently, a copy of the Rx packet header is copied into the the sk_buff private data so that we can advance the pointer into the buffer, potentially discarding the original. At the moment, this copy is held in network byte order, but this means we're doing a lot of unnecessary translations. The reasons it was done this way are that we need the values in network byte order occasionally and we can use the copy, slightly modified, as part of an iov array when sending an ack or an abort packet. However, it seems more reasonable on review that it would be better kept in host byte order and that we make up a new header when we want to send another packet. To this end, rename the original header struct to rxrpc_wire_header (with BE fields) and institute a variant called rxrpc_host_header that has host order fields. Change the struct in the sk_buff private data into an rxrpc_host_header and translate the values when filling it in. This further allows us to keep values kept in various structures in host byte order rather than network byte order and allows removal of some fields that are byteswapped duplicates. Signed-off-by: David Howells <dhowells@redhat.com>
2016-03-04 22:53:46 +07:00
if (rx->srx.srx_service == sp->hdr.serviceId &&
[AF_RXRPC]: Provide secure RxRPC sockets for use by userspace and kernel both Provide AF_RXRPC sockets that can be used to talk to AFS servers, or serve answers to AFS clients. KerberosIV security is fully supported. The patches and some example test programs can be found in: http://people.redhat.com/~dhowells/rxrpc/ This will eventually replace the old implementation of kernel-only RxRPC currently resident in net/rxrpc/. Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-27 05:48:28 +07:00
rx->sk.sk_state != RXRPC_CLOSE)
goto found_service;
}
read_unlock_bh(&local->services_lock);
goto invalid_service;
found_service:
rxrpc: Keep the skb private record of the Rx header in host byte order Currently, a copy of the Rx packet header is copied into the the sk_buff private data so that we can advance the pointer into the buffer, potentially discarding the original. At the moment, this copy is held in network byte order, but this means we're doing a lot of unnecessary translations. The reasons it was done this way are that we need the values in network byte order occasionally and we can use the copy, slightly modified, as part of an iov array when sending an ack or an abort packet. However, it seems more reasonable on review that it would be better kept in host byte order and that we make up a new header when we want to send another packet. To this end, rename the original header struct to rxrpc_wire_header (with BE fields) and institute a variant called rxrpc_host_header that has host order fields. Change the struct in the sk_buff private data into an rxrpc_host_header and translate the values when filling it in. This further allows us to keep values kept in various structures in host byte order rather than network byte order and allows removal of some fields that are byteswapped duplicates. Signed-off-by: David Howells <dhowells@redhat.com>
2016-03-04 22:53:46 +07:00
_debug("found service %hd", rx->srx.srx_service);
[AF_RXRPC]: Provide secure RxRPC sockets for use by userspace and kernel both Provide AF_RXRPC sockets that can be used to talk to AFS servers, or serve answers to AFS clients. KerberosIV security is fully supported. The patches and some example test programs can be found in: http://people.redhat.com/~dhowells/rxrpc/ This will eventually replace the old implementation of kernel-only RxRPC currently resident in net/rxrpc/. Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-27 05:48:28 +07:00
if (sk_acceptq_is_full(&rx->sk))
goto backlog_full;
sk_acceptq_added(&rx->sk);
read_unlock_bh(&local->services_lock);
ret = rxrpc_accept_incoming_call(local, rx, skb, &srx);
if (ret < 0)
sk_acceptq_removed(&rx->sk);
switch (ret) {
case -ECONNRESET: /* old calls are ignored */
case -ECONNABORTED: /* aborted calls are reaborted or ignored */
case 0:
rxrpc: Rework local endpoint management Rework the local RxRPC endpoint management. Local endpoint objects are maintained in a flat list as before. This should be okay as there shouldn't be more than one per open AF_RXRPC socket (there can be fewer as local endpoints can be shared if their local service ID is 0 and they share the same local transport parameters). Changes: (1) Local endpoints may now only be shared if they have local service ID 0 (ie. they're not being used for listening). This prevents a scenario where process A is listening of the Cache Manager port and process B contacts a fileserver - which may then attempt to send CM requests back to B. But if A and B are sharing a local endpoint, A will get the CM requests meant for B. (2) We use a mutex to handle lookups and don't provide RCU-only lookups since we only expect to access the list when opening a socket or destroying an endpoint. The local endpoint object is pointed to by the transport socket's sk_user_data for the life of the transport socket - allowing us to refer to it directly from the sk_data_ready and sk_error_report callbacks. (3) atomic_inc_not_zero() now exists and can be used to only share a local endpoint if the last reference hasn't yet gone. (4) We can remove rxrpc_local_lock - a spinlock that had to be taken with BH processing disabled given that we assume sk_user_data won't change under us. (5) The transport socket is shut down before we clear the sk_user_data pointer so that we can be sure that the transport socket's callbacks won't be invoked once the RCU destruction is scheduled. (6) Local endpoints have a work item that handles both destruction and event processing. The means that destruction doesn't then need to wait for event processing. The event queues can then be cleared after the transport socket is shut down. (7) Local endpoints are no longer available for resurrection beyond the life of the sockets that had them open. As soon as their last ref goes, they are scheduled for destruction and may not have their usage count moved from 0. Signed-off-by: David Howells <dhowells@redhat.com>
2016-04-04 20:00:35 +07:00
return;
[AF_RXRPC]: Provide secure RxRPC sockets for use by userspace and kernel both Provide AF_RXRPC sockets that can be used to talk to AFS servers, or serve answers to AFS clients. KerberosIV security is fully supported. The patches and some example test programs can be found in: http://people.redhat.com/~dhowells/rxrpc/ This will eventually replace the old implementation of kernel-only RxRPC currently resident in net/rxrpc/. Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-27 05:48:28 +07:00
case -ECONNREFUSED:
goto invalid_service;
case -EBUSY:
goto busy;
case -EKEYREJECTED:
goto security_mismatch;
default:
BUG();
}
backlog_full:
read_unlock_bh(&local->services_lock);
busy:
rxrpc: Keep the skb private record of the Rx header in host byte order Currently, a copy of the Rx packet header is copied into the the sk_buff private data so that we can advance the pointer into the buffer, potentially discarding the original. At the moment, this copy is held in network byte order, but this means we're doing a lot of unnecessary translations. The reasons it was done this way are that we need the values in network byte order occasionally and we can use the copy, slightly modified, as part of an iov array when sending an ack or an abort packet. However, it seems more reasonable on review that it would be better kept in host byte order and that we make up a new header when we want to send another packet. To this end, rename the original header struct to rxrpc_wire_header (with BE fields) and institute a variant called rxrpc_host_header that has host order fields. Change the struct in the sk_buff private data into an rxrpc_host_header and translate the values when filling it in. This further allows us to keep values kept in various structures in host byte order rather than network byte order and allows removal of some fields that are byteswapped duplicates. Signed-off-by: David Howells <dhowells@redhat.com>
2016-03-04 22:53:46 +07:00
rxrpc_busy(local, &srx, &whdr);
[AF_RXRPC]: Provide secure RxRPC sockets for use by userspace and kernel both Provide AF_RXRPC sockets that can be used to talk to AFS servers, or serve answers to AFS clients. KerberosIV security is fully supported. The patches and some example test programs can be found in: http://people.redhat.com/~dhowells/rxrpc/ This will eventually replace the old implementation of kernel-only RxRPC currently resident in net/rxrpc/. Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-27 05:48:28 +07:00
rxrpc_free_skb(skb);
rxrpc: Rework local endpoint management Rework the local RxRPC endpoint management. Local endpoint objects are maintained in a flat list as before. This should be okay as there shouldn't be more than one per open AF_RXRPC socket (there can be fewer as local endpoints can be shared if their local service ID is 0 and they share the same local transport parameters). Changes: (1) Local endpoints may now only be shared if they have local service ID 0 (ie. they're not being used for listening). This prevents a scenario where process A is listening of the Cache Manager port and process B contacts a fileserver - which may then attempt to send CM requests back to B. But if A and B are sharing a local endpoint, A will get the CM requests meant for B. (2) We use a mutex to handle lookups and don't provide RCU-only lookups since we only expect to access the list when opening a socket or destroying an endpoint. The local endpoint object is pointed to by the transport socket's sk_user_data for the life of the transport socket - allowing us to refer to it directly from the sk_data_ready and sk_error_report callbacks. (3) atomic_inc_not_zero() now exists and can be used to only share a local endpoint if the last reference hasn't yet gone. (4) We can remove rxrpc_local_lock - a spinlock that had to be taken with BH processing disabled given that we assume sk_user_data won't change under us. (5) The transport socket is shut down before we clear the sk_user_data pointer so that we can be sure that the transport socket's callbacks won't be invoked once the RCU destruction is scheduled. (6) Local endpoints have a work item that handles both destruction and event processing. The means that destruction doesn't then need to wait for event processing. The event queues can then be cleared after the transport socket is shut down. (7) Local endpoints are no longer available for resurrection beyond the life of the sockets that had them open. As soon as their last ref goes, they are scheduled for destruction and may not have their usage count moved from 0. Signed-off-by: David Howells <dhowells@redhat.com>
2016-04-04 20:00:35 +07:00
return;
[AF_RXRPC]: Provide secure RxRPC sockets for use by userspace and kernel both Provide AF_RXRPC sockets that can be used to talk to AFS servers, or serve answers to AFS clients. KerberosIV security is fully supported. The patches and some example test programs can be found in: http://people.redhat.com/~dhowells/rxrpc/ This will eventually replace the old implementation of kernel-only RxRPC currently resident in net/rxrpc/. Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-27 05:48:28 +07:00
rxrpc: Move peer lookup from call-accept to new-incoming-conn Move the lookup of a peer from a call that's being accepted into the function that creates a new incoming connection. This will allow us to avoid incrementing the peer's usage count in some cases in future. Note that I haven't bother to integrate rxrpc_get_addr_from_skb() with rxrpc_extract_addr_from_skb() as I'm going to delete the former in the very near future. Signed-off-by: David Howells <dhowells@redhat.com>
2016-06-29 20:40:39 +07:00
drop:
rxrpc_free_skb(skb);
return;
[AF_RXRPC]: Provide secure RxRPC sockets for use by userspace and kernel both Provide AF_RXRPC sockets that can be used to talk to AFS servers, or serve answers to AFS clients. KerberosIV security is fully supported. The patches and some example test programs can be found in: http://people.redhat.com/~dhowells/rxrpc/ This will eventually replace the old implementation of kernel-only RxRPC currently resident in net/rxrpc/. Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-27 05:48:28 +07:00
invalid_service:
skb->priority = RX_INVALID_OPERATION;
rxrpc_reject_packet(local, skb);
rxrpc: Rework local endpoint management Rework the local RxRPC endpoint management. Local endpoint objects are maintained in a flat list as before. This should be okay as there shouldn't be more than one per open AF_RXRPC socket (there can be fewer as local endpoints can be shared if their local service ID is 0 and they share the same local transport parameters). Changes: (1) Local endpoints may now only be shared if they have local service ID 0 (ie. they're not being used for listening). This prevents a scenario where process A is listening of the Cache Manager port and process B contacts a fileserver - which may then attempt to send CM requests back to B. But if A and B are sharing a local endpoint, A will get the CM requests meant for B. (2) We use a mutex to handle lookups and don't provide RCU-only lookups since we only expect to access the list when opening a socket or destroying an endpoint. The local endpoint object is pointed to by the transport socket's sk_user_data for the life of the transport socket - allowing us to refer to it directly from the sk_data_ready and sk_error_report callbacks. (3) atomic_inc_not_zero() now exists and can be used to only share a local endpoint if the last reference hasn't yet gone. (4) We can remove rxrpc_local_lock - a spinlock that had to be taken with BH processing disabled given that we assume sk_user_data won't change under us. (5) The transport socket is shut down before we clear the sk_user_data pointer so that we can be sure that the transport socket's callbacks won't be invoked once the RCU destruction is scheduled. (6) Local endpoints have a work item that handles both destruction and event processing. The means that destruction doesn't then need to wait for event processing. The event queues can then be cleared after the transport socket is shut down. (7) Local endpoints are no longer available for resurrection beyond the life of the sockets that had them open. As soon as their last ref goes, they are scheduled for destruction and may not have their usage count moved from 0. Signed-off-by: David Howells <dhowells@redhat.com>
2016-04-04 20:00:35 +07:00
return;
[AF_RXRPC]: Provide secure RxRPC sockets for use by userspace and kernel both Provide AF_RXRPC sockets that can be used to talk to AFS servers, or serve answers to AFS clients. KerberosIV security is fully supported. The patches and some example test programs can be found in: http://people.redhat.com/~dhowells/rxrpc/ This will eventually replace the old implementation of kernel-only RxRPC currently resident in net/rxrpc/. Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-27 05:48:28 +07:00
/* can't change connection security type mid-flow */
security_mismatch:
skb->priority = RX_PROTOCOL_ERROR;
rxrpc_reject_packet(local, skb);
rxrpc: Rework local endpoint management Rework the local RxRPC endpoint management. Local endpoint objects are maintained in a flat list as before. This should be okay as there shouldn't be more than one per open AF_RXRPC socket (there can be fewer as local endpoints can be shared if their local service ID is 0 and they share the same local transport parameters). Changes: (1) Local endpoints may now only be shared if they have local service ID 0 (ie. they're not being used for listening). This prevents a scenario where process A is listening of the Cache Manager port and process B contacts a fileserver - which may then attempt to send CM requests back to B. But if A and B are sharing a local endpoint, A will get the CM requests meant for B. (2) We use a mutex to handle lookups and don't provide RCU-only lookups since we only expect to access the list when opening a socket or destroying an endpoint. The local endpoint object is pointed to by the transport socket's sk_user_data for the life of the transport socket - allowing us to refer to it directly from the sk_data_ready and sk_error_report callbacks. (3) atomic_inc_not_zero() now exists and can be used to only share a local endpoint if the last reference hasn't yet gone. (4) We can remove rxrpc_local_lock - a spinlock that had to be taken with BH processing disabled given that we assume sk_user_data won't change under us. (5) The transport socket is shut down before we clear the sk_user_data pointer so that we can be sure that the transport socket's callbacks won't be invoked once the RCU destruction is scheduled. (6) Local endpoints have a work item that handles both destruction and event processing. The means that destruction doesn't then need to wait for event processing. The event queues can then be cleared after the transport socket is shut down. (7) Local endpoints are no longer available for resurrection beyond the life of the sockets that had them open. As soon as their last ref goes, they are scheduled for destruction and may not have their usage count moved from 0. Signed-off-by: David Howells <dhowells@redhat.com>
2016-04-04 20:00:35 +07:00
return;
[AF_RXRPC]: Provide secure RxRPC sockets for use by userspace and kernel both Provide AF_RXRPC sockets that can be used to talk to AFS servers, or serve answers to AFS clients. KerberosIV security is fully supported. The patches and some example test programs can be found in: http://people.redhat.com/~dhowells/rxrpc/ This will eventually replace the old implementation of kernel-only RxRPC currently resident in net/rxrpc/. Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-27 05:48:28 +07:00
}
/*
* handle acceptance of a call by userspace
* - assign the user call ID to the call at the front of the queue
*/
[AF_RXRPC]: Add an interface to the AF_RXRPC module for the AFS filesystem to use Add an interface to the AF_RXRPC module so that the AFS filesystem module can more easily make use of the services available. AFS still opens a socket but then uses the action functions in lieu of sendmsg() and registers an intercept functions to grab messages before they're queued on the socket Rx queue. This permits AFS (or whatever) to: (1) Avoid the overhead of using the recvmsg() call. (2) Use different keys directly on individual client calls on one socket rather than having to open a whole slew of sockets, one for each key it might want to use. (3) Avoid calling request_key() at the point of issue of a call or opening of a socket. This is done instead by AFS at the point of open(), unlink() or other VFS operation and the key handed through. (4) Request the use of something other than GFP_KERNEL to allocate memory. Furthermore: (*) The socket buffer markings used by RxRPC are made available for AFS so that it can interpret the cooked RxRPC messages itself. (*) rxgen (un)marshalling abort codes are made available. The following documentation for the kernel interface is added to Documentation/networking/rxrpc.txt: ========================= AF_RXRPC KERNEL INTERFACE ========================= The AF_RXRPC module also provides an interface for use by in-kernel utilities such as the AFS filesystem. This permits such a utility to: (1) Use different keys directly on individual client calls on one socket rather than having to open a whole slew of sockets, one for each key it might want to use. (2) Avoid having RxRPC call request_key() at the point of issue of a call or opening of a socket. Instead the utility is responsible for requesting a key at the appropriate point. AFS, for instance, would do this during VFS operations such as open() or unlink(). The key is then handed through when the call is initiated. (3) Request the use of something other than GFP_KERNEL to allocate memory. (4) Avoid the overhead of using the recvmsg() call. RxRPC messages can be intercepted before they get put into the socket Rx queue and the socket buffers manipulated directly. To use the RxRPC facility, a kernel utility must still open an AF_RXRPC socket, bind an addess as appropriate and listen if it's to be a server socket, but then it passes this to the kernel interface functions. The kernel interface functions are as follows: (*) Begin a new client call. struct rxrpc_call * rxrpc_kernel_begin_call(struct socket *sock, struct sockaddr_rxrpc *srx, struct key *key, unsigned long user_call_ID, gfp_t gfp); This allocates the infrastructure to make a new RxRPC call and assigns call and connection numbers. The call will be made on the UDP port that the socket is bound to. The call will go to the destination address of a connected client socket unless an alternative is supplied (srx is non-NULL). If a key is supplied then this will be used to secure the call instead of the key bound to the socket with the RXRPC_SECURITY_KEY sockopt. Calls secured in this way will still share connections if at all possible. The user_call_ID is equivalent to that supplied to sendmsg() in the control data buffer. It is entirely feasible to use this to point to a kernel data structure. If this function is successful, an opaque reference to the RxRPC call is returned. The caller now holds a reference on this and it must be properly ended. (*) End a client call. void rxrpc_kernel_end_call(struct rxrpc_call *call); This is used to end a previously begun call. The user_call_ID is expunged from AF_RXRPC's knowledge and will not be seen again in association with the specified call. (*) Send data through a call. int rxrpc_kernel_send_data(struct rxrpc_call *call, struct msghdr *msg, size_t len); This is used to supply either the request part of a client call or the reply part of a server call. msg.msg_iovlen and msg.msg_iov specify the data buffers to be used. msg_iov may not be NULL and must point exclusively to in-kernel virtual addresses. msg.msg_flags may be given MSG_MORE if there will be subsequent data sends for this call. The msg must not specify a destination address, control data or any flags other than MSG_MORE. len is the total amount of data to transmit. (*) Abort a call. void rxrpc_kernel_abort_call(struct rxrpc_call *call, u32 abort_code); This is used to abort a call if it's still in an abortable state. The abort code specified will be placed in the ABORT message sent. (*) Intercept received RxRPC messages. typedef void (*rxrpc_interceptor_t)(struct sock *sk, unsigned long user_call_ID, struct sk_buff *skb); void rxrpc_kernel_intercept_rx_messages(struct socket *sock, rxrpc_interceptor_t interceptor); This installs an interceptor function on the specified AF_RXRPC socket. All messages that would otherwise wind up in the socket's Rx queue are then diverted to this function. Note that care must be taken to process the messages in the right order to maintain DATA message sequentiality. The interceptor function itself is provided with the address of the socket and handling the incoming message, the ID assigned by the kernel utility to the call and the socket buffer containing the message. The skb->mark field indicates the type of message: MARK MEANING =============================== ======================================= RXRPC_SKB_MARK_DATA Data message RXRPC_SKB_MARK_FINAL_ACK Final ACK received for an incoming call RXRPC_SKB_MARK_BUSY Client call rejected as server busy RXRPC_SKB_MARK_REMOTE_ABORT Call aborted by peer RXRPC_SKB_MARK_NET_ERROR Network error detected RXRPC_SKB_MARK_LOCAL_ERROR Local error encountered RXRPC_SKB_MARK_NEW_CALL New incoming call awaiting acceptance The remote abort message can be probed with rxrpc_kernel_get_abort_code(). The two error messages can be probed with rxrpc_kernel_get_error_number(). A new call can be accepted with rxrpc_kernel_accept_call(). Data messages can have their contents extracted with the usual bunch of socket buffer manipulation functions. A data message can be determined to be the last one in a sequence with rxrpc_kernel_is_data_last(). When a data message has been used up, rxrpc_kernel_data_delivered() should be called on it.. Non-data messages should be handled to rxrpc_kernel_free_skb() to dispose of. It is possible to get extra refs on all types of message for later freeing, but this may pin the state of a call until the message is finally freed. (*) Accept an incoming call. struct rxrpc_call * rxrpc_kernel_accept_call(struct socket *sock, unsigned long user_call_ID); This is used to accept an incoming call and to assign it a call ID. This function is similar to rxrpc_kernel_begin_call() and calls accepted must be ended in the same way. If this function is successful, an opaque reference to the RxRPC call is returned. The caller now holds a reference on this and it must be properly ended. (*) Reject an incoming call. int rxrpc_kernel_reject_call(struct socket *sock); This is used to reject the first incoming call on the socket's queue with a BUSY message. -ENODATA is returned if there were no incoming calls. Other errors may be returned if the call had been aborted (-ECONNABORTED) or had timed out (-ETIME). (*) Record the delivery of a data message and free it. void rxrpc_kernel_data_delivered(struct sk_buff *skb); This is used to record a data message as having been delivered and to update the ACK state for the call. The socket buffer will be freed. (*) Free a message. void rxrpc_kernel_free_skb(struct sk_buff *skb); This is used to free a non-DATA socket buffer intercepted from an AF_RXRPC socket. (*) Determine if a data message is the last one on a call. bool rxrpc_kernel_is_data_last(struct sk_buff *skb); This is used to determine if a socket buffer holds the last data message to be received for a call (true will be returned if it does, false if not). The data message will be part of the reply on a client call and the request on an incoming call. In the latter case there will be more messages, but in the former case there will not. (*) Get the abort code from an abort message. u32 rxrpc_kernel_get_abort_code(struct sk_buff *skb); This is used to extract the abort code from a remote abort message. (*) Get the error number from a local or network error message. int rxrpc_kernel_get_error_number(struct sk_buff *skb); This is used to extract the error number from a message indicating either a local error occurred or a network error occurred. Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-27 05:50:17 +07:00
struct rxrpc_call *rxrpc_accept_call(struct rxrpc_sock *rx,
rxrpc: Don't expose skbs to in-kernel users [ver #2] Don't expose skbs to in-kernel users, such as the AFS filesystem, but instead provide a notification hook the indicates that a call needs attention and another that indicates that there's a new call to be collected. This makes the following possibilities more achievable: (1) Call refcounting can be made simpler if skbs don't hold refs to calls. (2) skbs referring to non-data events will be able to be freed much sooner rather than being queued for AFS to pick up as rxrpc_kernel_recv_data will be able to consult the call state. (3) We can shortcut the receive phase when a call is remotely aborted because we don't have to go through all the packets to get to the one cancelling the operation. (4) It makes it easier to do encryption/decryption directly between AFS's buffers and sk_buffs. (5) Encryption/decryption can more easily be done in the AFS's thread contexts - usually that of the userspace process that issued a syscall - rather than in one of rxrpc's background threads on a workqueue. (6) AFS will be able to wait synchronously on a call inside AF_RXRPC. To make this work, the following interface function has been added: int rxrpc_kernel_recv_data( struct socket *sock, struct rxrpc_call *call, void *buffer, size_t bufsize, size_t *_offset, bool want_more, u32 *_abort_code); This is the recvmsg equivalent. It allows the caller to find out about the state of a specific call and to transfer received data into a buffer piecemeal. afs_extract_data() and rxrpc_kernel_recv_data() now do all the extraction logic between them. They don't wait synchronously yet because the socket lock needs to be dealt with. Five interface functions have been removed: rxrpc_kernel_is_data_last() rxrpc_kernel_get_abort_code() rxrpc_kernel_get_error_number() rxrpc_kernel_free_skb() rxrpc_kernel_data_consumed() As a temporary hack, sk_buffs going to an in-kernel call are queued on the rxrpc_call struct (->knlrecv_queue) rather than being handed over to the in-kernel user. To process the queue internally, a temporary function, temp_deliver_data() has been added. This will be replaced with common code between the rxrpc_recvmsg() path and the kernel_rxrpc_recv_data() path in a future patch. Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-08-31 02:42:14 +07:00
unsigned long user_call_ID,
rxrpc_notify_rx_t notify_rx)
[AF_RXRPC]: Provide secure RxRPC sockets for use by userspace and kernel both Provide AF_RXRPC sockets that can be used to talk to AFS servers, or serve answers to AFS clients. KerberosIV security is fully supported. The patches and some example test programs can be found in: http://people.redhat.com/~dhowells/rxrpc/ This will eventually replace the old implementation of kernel-only RxRPC currently resident in net/rxrpc/. Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-27 05:48:28 +07:00
{
struct rxrpc_call *call;
struct rb_node *parent, **pp;
int ret;
_enter(",%lx", user_call_ID);
ASSERT(!irqs_disabled());
write_lock(&rx->call_lock);
ret = -ENODATA;
if (list_empty(&rx->acceptq))
goto out;
/* check the user ID isn't already in use */
ret = -EBADSLT;
pp = &rx->calls.rb_node;
parent = NULL;
while (*pp) {
parent = *pp;
call = rb_entry(parent, struct rxrpc_call, sock_node);
if (user_call_ID < call->user_call_ID)
pp = &(*pp)->rb_left;
else if (user_call_ID > call->user_call_ID)
pp = &(*pp)->rb_right;
else
goto out;
}
/* dequeue the first call and check it's still valid */
call = list_entry(rx->acceptq.next, struct rxrpc_call, accept_link);
list_del_init(&call->accept_link);
sk_acceptq_removed(&rx->sk);
rxrpc: Trace rxrpc_call usage Add a trace event for debuging rxrpc_call struct usage. Signed-off-by: David Howells <dhowells@redhat.com>
2016-08-30 15:49:29 +07:00
rxrpc_see_call(call);
[AF_RXRPC]: Provide secure RxRPC sockets for use by userspace and kernel both Provide AF_RXRPC sockets that can be used to talk to AFS servers, or serve answers to AFS clients. KerberosIV security is fully supported. The patches and some example test programs can be found in: http://people.redhat.com/~dhowells/rxrpc/ This will eventually replace the old implementation of kernel-only RxRPC currently resident in net/rxrpc/. Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-27 05:48:28 +07:00
write_lock_bh(&call->state_lock);
switch (call->state) {
case RXRPC_CALL_SERVER_ACCEPTING:
call->state = RXRPC_CALL_SERVER_RECV_REQUEST;
break;
rxrpc: Calls should only have one terminal state Condense the terminal states of a call state machine to a single state, plus a separate completion type value. The value is then set, along with error and abort code values, only when the call is transitioned to the completion state. Helpers are provided to simplify this. Signed-off-by: David Howells <dhowells@redhat.com>
2016-08-30 15:49:28 +07:00
case RXRPC_CALL_COMPLETE:
ret = call->error;
[AF_RXRPC]: Provide secure RxRPC sockets for use by userspace and kernel both Provide AF_RXRPC sockets that can be used to talk to AFS servers, or serve answers to AFS clients. KerberosIV security is fully supported. The patches and some example test programs can be found in: http://people.redhat.com/~dhowells/rxrpc/ This will eventually replace the old implementation of kernel-only RxRPC currently resident in net/rxrpc/. Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-27 05:48:28 +07:00
goto out_release;
default:
BUG();
}
/* formalise the acceptance */
rxrpc: Improve the call tracking tracepoint Improve the call tracking tracepoint by showing more differentiation between some of the put and get events, including: (1) Getting and putting refs for the socket call user ID tree. (2) Getting and putting refs for queueing and failing to queue the call processor work item. Note that these aren't necessarily used in this patch, but will be taken advantage of in future patches. An enum is added for the event subtype numbers rather than coding them directly as decimal numbers and a table of 3-letter strings is provided rather than a sequence of ?: operators. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-07 20:34:21 +07:00
rxrpc_get_call(call, rxrpc_call_got_userid);
rxrpc: Don't expose skbs to in-kernel users [ver #2] Don't expose skbs to in-kernel users, such as the AFS filesystem, but instead provide a notification hook the indicates that a call needs attention and another that indicates that there's a new call to be collected. This makes the following possibilities more achievable: (1) Call refcounting can be made simpler if skbs don't hold refs to calls. (2) skbs referring to non-data events will be able to be freed much sooner rather than being queued for AFS to pick up as rxrpc_kernel_recv_data will be able to consult the call state. (3) We can shortcut the receive phase when a call is remotely aborted because we don't have to go through all the packets to get to the one cancelling the operation. (4) It makes it easier to do encryption/decryption directly between AFS's buffers and sk_buffs. (5) Encryption/decryption can more easily be done in the AFS's thread contexts - usually that of the userspace process that issued a syscall - rather than in one of rxrpc's background threads on a workqueue. (6) AFS will be able to wait synchronously on a call inside AF_RXRPC. To make this work, the following interface function has been added: int rxrpc_kernel_recv_data( struct socket *sock, struct rxrpc_call *call, void *buffer, size_t bufsize, size_t *_offset, bool want_more, u32 *_abort_code); This is the recvmsg equivalent. It allows the caller to find out about the state of a specific call and to transfer received data into a buffer piecemeal. afs_extract_data() and rxrpc_kernel_recv_data() now do all the extraction logic between them. They don't wait synchronously yet because the socket lock needs to be dealt with. Five interface functions have been removed: rxrpc_kernel_is_data_last() rxrpc_kernel_get_abort_code() rxrpc_kernel_get_error_number() rxrpc_kernel_free_skb() rxrpc_kernel_data_consumed() As a temporary hack, sk_buffs going to an in-kernel call are queued on the rxrpc_call struct (->knlrecv_queue) rather than being handed over to the in-kernel user. To process the queue internally, a temporary function, temp_deliver_data() has been added. This will be replaced with common code between the rxrpc_recvmsg() path and the kernel_rxrpc_recv_data() path in a future patch. Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-08-31 02:42:14 +07:00
call->notify_rx = notify_rx;
[AF_RXRPC]: Provide secure RxRPC sockets for use by userspace and kernel both Provide AF_RXRPC sockets that can be used to talk to AFS servers, or serve answers to AFS clients. KerberosIV security is fully supported. The patches and some example test programs can be found in: http://people.redhat.com/~dhowells/rxrpc/ This will eventually replace the old implementation of kernel-only RxRPC currently resident in net/rxrpc/. Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-27 05:48:28 +07:00
call->user_call_ID = user_call_ID;
rb_link_node(&call->sock_node, parent, pp);
rb_insert_color(&call->sock_node, &rx->calls);
if (test_and_set_bit(RXRPC_CALL_HAS_USERID, &call->flags))
BUG();
rxrpc: Rename call events to begin RXRPC_CALL_EV_ Rename call event names to begin RXRPC_CALL_EV_ to distinguish them from the flags. Signed-off-by: David Howells <dhowells@redhat.com>
2016-03-04 22:53:46 +07:00
if (test_and_set_bit(RXRPC_CALL_EV_ACCEPTED, &call->events))
[AF_RXRPC]: Provide secure RxRPC sockets for use by userspace and kernel both Provide AF_RXRPC sockets that can be used to talk to AFS servers, or serve answers to AFS clients. KerberosIV security is fully supported. The patches and some example test programs can be found in: http://people.redhat.com/~dhowells/rxrpc/ This will eventually replace the old implementation of kernel-only RxRPC currently resident in net/rxrpc/. Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-27 05:48:28 +07:00
BUG();
write_unlock_bh(&call->state_lock);
write_unlock(&rx->call_lock);
rxrpc: Calls shouldn't hold socket refs rxrpc calls shouldn't hold refs on the sock struct. This was done so that the socket wouldn't go away whilst the call was in progress, such that the call could reach the socket's queues. However, we can mark the socket as requiring an RCU release and rely on the RCU read lock. To make this work, we do: (1) rxrpc_release_call() removes the call's call user ID. This is now only called from socket operations and not from the call processor: rxrpc_accept_call() / rxrpc_kernel_accept_call() rxrpc_reject_call() / rxrpc_kernel_reject_call() rxrpc_kernel_end_call() rxrpc_release_calls_on_socket() rxrpc_recvmsg() Though it is also called in the cleanup path of rxrpc_accept_incoming_call() before we assign a user ID. (2) Pass the socket pointer into rxrpc_release_call() rather than getting it from the call so that we can get rid of uninitialised calls. (3) Fix call processor queueing to pass a ref to the work queue and to release that ref at the end of the processor function (or to pass it back to the work queue if we have to requeue). (4) Skip out of the call processor function asap if the call is complete and don't requeue it if the call is complete. (5) Clean up the call immediately that the refcount reaches 0 rather than trying to defer it. Actual deallocation is deferred to RCU, however. (6) Don't hold socket refs for allocated calls. (7) Use the RCU read lock when queueing a message on a socket and treat the call's socket pointer according to RCU rules and check it for NULL. We also need to use the RCU read lock when viewing a call through procfs. (8) Transmit the final ACK/ABORT to a client call in rxrpc_release_call() if this hasn't been done yet so that we can then disconnect the call. Once the call is disconnected, it won't have any access to the connection struct and the UDP socket for the call work processor to be able to send the ACK. Terminal retransmission will be handled by the connection processor. (9) Release all calls immediately on the closing of a socket rather than trying to defer this. Incomplete calls will be aborted. The call refcount model is much simplified. Refs are held on the call by: (1) A socket's user ID tree. (2) A socket's incoming call secureq and acceptq. (3) A kernel service that has a call in progress. (4) A queued call work processor. We have to take care to put any call that we failed to queue. (5) sk_buffs on a socket's receive queue. A future patch will get rid of this. Whilst we're at it, we can do: (1) Get rid of the RXRPC_CALL_EV_RELEASE event. Release is now done entirely from the socket routines and never from the call's processor. (2) Get rid of the RXRPC_CALL_DEAD state. Calls now end in the RXRPC_CALL_COMPLETE state. (3) Get rid of the rxrpc_call::destroyer work item. Calls are now torn down when their refcount reaches 0 and then handed over to RCU for final cleanup. (4) Get rid of the rxrpc_call::deadspan timer. Calls are cleaned up immediately they're finished with and don't hang around. Post-completion retransmission is handled by the connection processor once the call is disconnected. (5) Get rid of the dead call expiry setting as there's no longer a timer to set. (6) rxrpc_destroy_all_calls() can just check that the call list is empty. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-07 15:19:31 +07:00
rxrpc_queue_call(call);
[AF_RXRPC]: Add an interface to the AF_RXRPC module for the AFS filesystem to use Add an interface to the AF_RXRPC module so that the AFS filesystem module can more easily make use of the services available. AFS still opens a socket but then uses the action functions in lieu of sendmsg() and registers an intercept functions to grab messages before they're queued on the socket Rx queue. This permits AFS (or whatever) to: (1) Avoid the overhead of using the recvmsg() call. (2) Use different keys directly on individual client calls on one socket rather than having to open a whole slew of sockets, one for each key it might want to use. (3) Avoid calling request_key() at the point of issue of a call or opening of a socket. This is done instead by AFS at the point of open(), unlink() or other VFS operation and the key handed through. (4) Request the use of something other than GFP_KERNEL to allocate memory. Furthermore: (*) The socket buffer markings used by RxRPC are made available for AFS so that it can interpret the cooked RxRPC messages itself. (*) rxgen (un)marshalling abort codes are made available. The following documentation for the kernel interface is added to Documentation/networking/rxrpc.txt: ========================= AF_RXRPC KERNEL INTERFACE ========================= The AF_RXRPC module also provides an interface for use by in-kernel utilities such as the AFS filesystem. This permits such a utility to: (1) Use different keys directly on individual client calls on one socket rather than having to open a whole slew of sockets, one for each key it might want to use. (2) Avoid having RxRPC call request_key() at the point of issue of a call or opening of a socket. Instead the utility is responsible for requesting a key at the appropriate point. AFS, for instance, would do this during VFS operations such as open() or unlink(). The key is then handed through when the call is initiated. (3) Request the use of something other than GFP_KERNEL to allocate memory. (4) Avoid the overhead of using the recvmsg() call. RxRPC messages can be intercepted before they get put into the socket Rx queue and the socket buffers manipulated directly. To use the RxRPC facility, a kernel utility must still open an AF_RXRPC socket, bind an addess as appropriate and listen if it's to be a server socket, but then it passes this to the kernel interface functions. The kernel interface functions are as follows: (*) Begin a new client call. struct rxrpc_call * rxrpc_kernel_begin_call(struct socket *sock, struct sockaddr_rxrpc *srx, struct key *key, unsigned long user_call_ID, gfp_t gfp); This allocates the infrastructure to make a new RxRPC call and assigns call and connection numbers. The call will be made on the UDP port that the socket is bound to. The call will go to the destination address of a connected client socket unless an alternative is supplied (srx is non-NULL). If a key is supplied then this will be used to secure the call instead of the key bound to the socket with the RXRPC_SECURITY_KEY sockopt. Calls secured in this way will still share connections if at all possible. The user_call_ID is equivalent to that supplied to sendmsg() in the control data buffer. It is entirely feasible to use this to point to a kernel data structure. If this function is successful, an opaque reference to the RxRPC call is returned. The caller now holds a reference on this and it must be properly ended. (*) End a client call. void rxrpc_kernel_end_call(struct rxrpc_call *call); This is used to end a previously begun call. The user_call_ID is expunged from AF_RXRPC's knowledge and will not be seen again in association with the specified call. (*) Send data through a call. int rxrpc_kernel_send_data(struct rxrpc_call *call, struct msghdr *msg, size_t len); This is used to supply either the request part of a client call or the reply part of a server call. msg.msg_iovlen and msg.msg_iov specify the data buffers to be used. msg_iov may not be NULL and must point exclusively to in-kernel virtual addresses. msg.msg_flags may be given MSG_MORE if there will be subsequent data sends for this call. The msg must not specify a destination address, control data or any flags other than MSG_MORE. len is the total amount of data to transmit. (*) Abort a call. void rxrpc_kernel_abort_call(struct rxrpc_call *call, u32 abort_code); This is used to abort a call if it's still in an abortable state. The abort code specified will be placed in the ABORT message sent. (*) Intercept received RxRPC messages. typedef void (*rxrpc_interceptor_t)(struct sock *sk, unsigned long user_call_ID, struct sk_buff *skb); void rxrpc_kernel_intercept_rx_messages(struct socket *sock, rxrpc_interceptor_t interceptor); This installs an interceptor function on the specified AF_RXRPC socket. All messages that would otherwise wind up in the socket's Rx queue are then diverted to this function. Note that care must be taken to process the messages in the right order to maintain DATA message sequentiality. The interceptor function itself is provided with the address of the socket and handling the incoming message, the ID assigned by the kernel utility to the call and the socket buffer containing the message. The skb->mark field indicates the type of message: MARK MEANING =============================== ======================================= RXRPC_SKB_MARK_DATA Data message RXRPC_SKB_MARK_FINAL_ACK Final ACK received for an incoming call RXRPC_SKB_MARK_BUSY Client call rejected as server busy RXRPC_SKB_MARK_REMOTE_ABORT Call aborted by peer RXRPC_SKB_MARK_NET_ERROR Network error detected RXRPC_SKB_MARK_LOCAL_ERROR Local error encountered RXRPC_SKB_MARK_NEW_CALL New incoming call awaiting acceptance The remote abort message can be probed with rxrpc_kernel_get_abort_code(). The two error messages can be probed with rxrpc_kernel_get_error_number(). A new call can be accepted with rxrpc_kernel_accept_call(). Data messages can have their contents extracted with the usual bunch of socket buffer manipulation functions. A data message can be determined to be the last one in a sequence with rxrpc_kernel_is_data_last(). When a data message has been used up, rxrpc_kernel_data_delivered() should be called on it.. Non-data messages should be handled to rxrpc_kernel_free_skb() to dispose of. It is possible to get extra refs on all types of message for later freeing, but this may pin the state of a call until the message is finally freed. (*) Accept an incoming call. struct rxrpc_call * rxrpc_kernel_accept_call(struct socket *sock, unsigned long user_call_ID); This is used to accept an incoming call and to assign it a call ID. This function is similar to rxrpc_kernel_begin_call() and calls accepted must be ended in the same way. If this function is successful, an opaque reference to the RxRPC call is returned. The caller now holds a reference on this and it must be properly ended. (*) Reject an incoming call. int rxrpc_kernel_reject_call(struct socket *sock); This is used to reject the first incoming call on the socket's queue with a BUSY message. -ENODATA is returned if there were no incoming calls. Other errors may be returned if the call had been aborted (-ECONNABORTED) or had timed out (-ETIME). (*) Record the delivery of a data message and free it. void rxrpc_kernel_data_delivered(struct sk_buff *skb); This is used to record a data message as having been delivered and to update the ACK state for the call. The socket buffer will be freed. (*) Free a message. void rxrpc_kernel_free_skb(struct sk_buff *skb); This is used to free a non-DATA socket buffer intercepted from an AF_RXRPC socket. (*) Determine if a data message is the last one on a call. bool rxrpc_kernel_is_data_last(struct sk_buff *skb); This is used to determine if a socket buffer holds the last data message to be received for a call (true will be returned if it does, false if not). The data message will be part of the reply on a client call and the request on an incoming call. In the latter case there will be more messages, but in the former case there will not. (*) Get the abort code from an abort message. u32 rxrpc_kernel_get_abort_code(struct sk_buff *skb); This is used to extract the abort code from a remote abort message. (*) Get the error number from a local or network error message. int rxrpc_kernel_get_error_number(struct sk_buff *skb); This is used to extract the error number from a message indicating either a local error occurred or a network error occurred. Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-27 05:50:17 +07:00
_leave(" = %p{%d}", call, call->debug_id);
return call;
out_release:
write_unlock_bh(&call->state_lock);
rxrpc: Calls shouldn't hold socket refs rxrpc calls shouldn't hold refs on the sock struct. This was done so that the socket wouldn't go away whilst the call was in progress, such that the call could reach the socket's queues. However, we can mark the socket as requiring an RCU release and rely on the RCU read lock. To make this work, we do: (1) rxrpc_release_call() removes the call's call user ID. This is now only called from socket operations and not from the call processor: rxrpc_accept_call() / rxrpc_kernel_accept_call() rxrpc_reject_call() / rxrpc_kernel_reject_call() rxrpc_kernel_end_call() rxrpc_release_calls_on_socket() rxrpc_recvmsg() Though it is also called in the cleanup path of rxrpc_accept_incoming_call() before we assign a user ID. (2) Pass the socket pointer into rxrpc_release_call() rather than getting it from the call so that we can get rid of uninitialised calls. (3) Fix call processor queueing to pass a ref to the work queue and to release that ref at the end of the processor function (or to pass it back to the work queue if we have to requeue). (4) Skip out of the call processor function asap if the call is complete and don't requeue it if the call is complete. (5) Clean up the call immediately that the refcount reaches 0 rather than trying to defer it. Actual deallocation is deferred to RCU, however. (6) Don't hold socket refs for allocated calls. (7) Use the RCU read lock when queueing a message on a socket and treat the call's socket pointer according to RCU rules and check it for NULL. We also need to use the RCU read lock when viewing a call through procfs. (8) Transmit the final ACK/ABORT to a client call in rxrpc_release_call() if this hasn't been done yet so that we can then disconnect the call. Once the call is disconnected, it won't have any access to the connection struct and the UDP socket for the call work processor to be able to send the ACK. Terminal retransmission will be handled by the connection processor. (9) Release all calls immediately on the closing of a socket rather than trying to defer this. Incomplete calls will be aborted. The call refcount model is much simplified. Refs are held on the call by: (1) A socket's user ID tree. (2) A socket's incoming call secureq and acceptq. (3) A kernel service that has a call in progress. (4) A queued call work processor. We have to take care to put any call that we failed to queue. (5) sk_buffs on a socket's receive queue. A future patch will get rid of this. Whilst we're at it, we can do: (1) Get rid of the RXRPC_CALL_EV_RELEASE event. Release is now done entirely from the socket routines and never from the call's processor. (2) Get rid of the RXRPC_CALL_DEAD state. Calls now end in the RXRPC_CALL_COMPLETE state. (3) Get rid of the rxrpc_call::destroyer work item. Calls are now torn down when their refcount reaches 0 and then handed over to RCU for final cleanup. (4) Get rid of the rxrpc_call::deadspan timer. Calls are cleaned up immediately they're finished with and don't hang around. Post-completion retransmission is handled by the connection processor once the call is disconnected. (5) Get rid of the dead call expiry setting as there's no longer a timer to set. (6) rxrpc_destroy_all_calls() can just check that the call list is empty. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-07 15:19:31 +07:00
write_unlock(&rx->call_lock);
_debug("release %p", call);
rxrpc_release_call(rx, call);
_leave(" = %d", ret);
return ERR_PTR(ret);
[AF_RXRPC]: Add an interface to the AF_RXRPC module for the AFS filesystem to use Add an interface to the AF_RXRPC module so that the AFS filesystem module can more easily make use of the services available. AFS still opens a socket but then uses the action functions in lieu of sendmsg() and registers an intercept functions to grab messages before they're queued on the socket Rx queue. This permits AFS (or whatever) to: (1) Avoid the overhead of using the recvmsg() call. (2) Use different keys directly on individual client calls on one socket rather than having to open a whole slew of sockets, one for each key it might want to use. (3) Avoid calling request_key() at the point of issue of a call or opening of a socket. This is done instead by AFS at the point of open(), unlink() or other VFS operation and the key handed through. (4) Request the use of something other than GFP_KERNEL to allocate memory. Furthermore: (*) The socket buffer markings used by RxRPC are made available for AFS so that it can interpret the cooked RxRPC messages itself. (*) rxgen (un)marshalling abort codes are made available. The following documentation for the kernel interface is added to Documentation/networking/rxrpc.txt: ========================= AF_RXRPC KERNEL INTERFACE ========================= The AF_RXRPC module also provides an interface for use by in-kernel utilities such as the AFS filesystem. This permits such a utility to: (1) Use different keys directly on individual client calls on one socket rather than having to open a whole slew of sockets, one for each key it might want to use. (2) Avoid having RxRPC call request_key() at the point of issue of a call or opening of a socket. Instead the utility is responsible for requesting a key at the appropriate point. AFS, for instance, would do this during VFS operations such as open() or unlink(). The key is then handed through when the call is initiated. (3) Request the use of something other than GFP_KERNEL to allocate memory. (4) Avoid the overhead of using the recvmsg() call. RxRPC messages can be intercepted before they get put into the socket Rx queue and the socket buffers manipulated directly. To use the RxRPC facility, a kernel utility must still open an AF_RXRPC socket, bind an addess as appropriate and listen if it's to be a server socket, but then it passes this to the kernel interface functions. The kernel interface functions are as follows: (*) Begin a new client call. struct rxrpc_call * rxrpc_kernel_begin_call(struct socket *sock, struct sockaddr_rxrpc *srx, struct key *key, unsigned long user_call_ID, gfp_t gfp); This allocates the infrastructure to make a new RxRPC call and assigns call and connection numbers. The call will be made on the UDP port that the socket is bound to. The call will go to the destination address of a connected client socket unless an alternative is supplied (srx is non-NULL). If a key is supplied then this will be used to secure the call instead of the key bound to the socket with the RXRPC_SECURITY_KEY sockopt. Calls secured in this way will still share connections if at all possible. The user_call_ID is equivalent to that supplied to sendmsg() in the control data buffer. It is entirely feasible to use this to point to a kernel data structure. If this function is successful, an opaque reference to the RxRPC call is returned. The caller now holds a reference on this and it must be properly ended. (*) End a client call. void rxrpc_kernel_end_call(struct rxrpc_call *call); This is used to end a previously begun call. The user_call_ID is expunged from AF_RXRPC's knowledge and will not be seen again in association with the specified call. (*) Send data through a call. int rxrpc_kernel_send_data(struct rxrpc_call *call, struct msghdr *msg, size_t len); This is used to supply either the request part of a client call or the reply part of a server call. msg.msg_iovlen and msg.msg_iov specify the data buffers to be used. msg_iov may not be NULL and must point exclusively to in-kernel virtual addresses. msg.msg_flags may be given MSG_MORE if there will be subsequent data sends for this call. The msg must not specify a destination address, control data or any flags other than MSG_MORE. len is the total amount of data to transmit. (*) Abort a call. void rxrpc_kernel_abort_call(struct rxrpc_call *call, u32 abort_code); This is used to abort a call if it's still in an abortable state. The abort code specified will be placed in the ABORT message sent. (*) Intercept received RxRPC messages. typedef void (*rxrpc_interceptor_t)(struct sock *sk, unsigned long user_call_ID, struct sk_buff *skb); void rxrpc_kernel_intercept_rx_messages(struct socket *sock, rxrpc_interceptor_t interceptor); This installs an interceptor function on the specified AF_RXRPC socket. All messages that would otherwise wind up in the socket's Rx queue are then diverted to this function. Note that care must be taken to process the messages in the right order to maintain DATA message sequentiality. The interceptor function itself is provided with the address of the socket and handling the incoming message, the ID assigned by the kernel utility to the call and the socket buffer containing the message. The skb->mark field indicates the type of message: MARK MEANING =============================== ======================================= RXRPC_SKB_MARK_DATA Data message RXRPC_SKB_MARK_FINAL_ACK Final ACK received for an incoming call RXRPC_SKB_MARK_BUSY Client call rejected as server busy RXRPC_SKB_MARK_REMOTE_ABORT Call aborted by peer RXRPC_SKB_MARK_NET_ERROR Network error detected RXRPC_SKB_MARK_LOCAL_ERROR Local error encountered RXRPC_SKB_MARK_NEW_CALL New incoming call awaiting acceptance The remote abort message can be probed with rxrpc_kernel_get_abort_code(). The two error messages can be probed with rxrpc_kernel_get_error_number(). A new call can be accepted with rxrpc_kernel_accept_call(). Data messages can have their contents extracted with the usual bunch of socket buffer manipulation functions. A data message can be determined to be the last one in a sequence with rxrpc_kernel_is_data_last(). When a data message has been used up, rxrpc_kernel_data_delivered() should be called on it.. Non-data messages should be handled to rxrpc_kernel_free_skb() to dispose of. It is possible to get extra refs on all types of message for later freeing, but this may pin the state of a call until the message is finally freed. (*) Accept an incoming call. struct rxrpc_call * rxrpc_kernel_accept_call(struct socket *sock, unsigned long user_call_ID); This is used to accept an incoming call and to assign it a call ID. This function is similar to rxrpc_kernel_begin_call() and calls accepted must be ended in the same way. If this function is successful, an opaque reference to the RxRPC call is returned. The caller now holds a reference on this and it must be properly ended. (*) Reject an incoming call. int rxrpc_kernel_reject_call(struct socket *sock); This is used to reject the first incoming call on the socket's queue with a BUSY message. -ENODATA is returned if there were no incoming calls. Other errors may be returned if the call had been aborted (-ECONNABORTED) or had timed out (-ETIME). (*) Record the delivery of a data message and free it. void rxrpc_kernel_data_delivered(struct sk_buff *skb); This is used to record a data message as having been delivered and to update the ACK state for the call. The socket buffer will be freed. (*) Free a message. void rxrpc_kernel_free_skb(struct sk_buff *skb); This is used to free a non-DATA socket buffer intercepted from an AF_RXRPC socket. (*) Determine if a data message is the last one on a call. bool rxrpc_kernel_is_data_last(struct sk_buff *skb); This is used to determine if a socket buffer holds the last data message to be received for a call (true will be returned if it does, false if not). The data message will be part of the reply on a client call and the request on an incoming call. In the latter case there will be more messages, but in the former case there will not. (*) Get the abort code from an abort message. u32 rxrpc_kernel_get_abort_code(struct sk_buff *skb); This is used to extract the abort code from a remote abort message. (*) Get the error number from a local or network error message. int rxrpc_kernel_get_error_number(struct sk_buff *skb); This is used to extract the error number from a message indicating either a local error occurred or a network error occurred. Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-27 05:50:17 +07:00
out:
write_unlock(&rx->call_lock);
_leave(" = %d", ret);
return ERR_PTR(ret);
}
/*
rxrpc: Adjust some whitespace and comments Remove some excess whitespace, insert some missing spaces and adjust a couple of comments. Signed-off-by: David Howells <dhowells@redhat.com>
2016-03-04 22:56:19 +07:00
* Handle rejection of a call by userspace
[AF_RXRPC]: Add an interface to the AF_RXRPC module for the AFS filesystem to use Add an interface to the AF_RXRPC module so that the AFS filesystem module can more easily make use of the services available. AFS still opens a socket but then uses the action functions in lieu of sendmsg() and registers an intercept functions to grab messages before they're queued on the socket Rx queue. This permits AFS (or whatever) to: (1) Avoid the overhead of using the recvmsg() call. (2) Use different keys directly on individual client calls on one socket rather than having to open a whole slew of sockets, one for each key it might want to use. (3) Avoid calling request_key() at the point of issue of a call or opening of a socket. This is done instead by AFS at the point of open(), unlink() or other VFS operation and the key handed through. (4) Request the use of something other than GFP_KERNEL to allocate memory. Furthermore: (*) The socket buffer markings used by RxRPC are made available for AFS so that it can interpret the cooked RxRPC messages itself. (*) rxgen (un)marshalling abort codes are made available. The following documentation for the kernel interface is added to Documentation/networking/rxrpc.txt: ========================= AF_RXRPC KERNEL INTERFACE ========================= The AF_RXRPC module also provides an interface for use by in-kernel utilities such as the AFS filesystem. This permits such a utility to: (1) Use different keys directly on individual client calls on one socket rather than having to open a whole slew of sockets, one for each key it might want to use. (2) Avoid having RxRPC call request_key() at the point of issue of a call or opening of a socket. Instead the utility is responsible for requesting a key at the appropriate point. AFS, for instance, would do this during VFS operations such as open() or unlink(). The key is then handed through when the call is initiated. (3) Request the use of something other than GFP_KERNEL to allocate memory. (4) Avoid the overhead of using the recvmsg() call. RxRPC messages can be intercepted before they get put into the socket Rx queue and the socket buffers manipulated directly. To use the RxRPC facility, a kernel utility must still open an AF_RXRPC socket, bind an addess as appropriate and listen if it's to be a server socket, but then it passes this to the kernel interface functions. The kernel interface functions are as follows: (*) Begin a new client call. struct rxrpc_call * rxrpc_kernel_begin_call(struct socket *sock, struct sockaddr_rxrpc *srx, struct key *key, unsigned long user_call_ID, gfp_t gfp); This allocates the infrastructure to make a new RxRPC call and assigns call and connection numbers. The call will be made on the UDP port that the socket is bound to. The call will go to the destination address of a connected client socket unless an alternative is supplied (srx is non-NULL). If a key is supplied then this will be used to secure the call instead of the key bound to the socket with the RXRPC_SECURITY_KEY sockopt. Calls secured in this way will still share connections if at all possible. The user_call_ID is equivalent to that supplied to sendmsg() in the control data buffer. It is entirely feasible to use this to point to a kernel data structure. If this function is successful, an opaque reference to the RxRPC call is returned. The caller now holds a reference on this and it must be properly ended. (*) End a client call. void rxrpc_kernel_end_call(struct rxrpc_call *call); This is used to end a previously begun call. The user_call_ID is expunged from AF_RXRPC's knowledge and will not be seen again in association with the specified call. (*) Send data through a call. int rxrpc_kernel_send_data(struct rxrpc_call *call, struct msghdr *msg, size_t len); This is used to supply either the request part of a client call or the reply part of a server call. msg.msg_iovlen and msg.msg_iov specify the data buffers to be used. msg_iov may not be NULL and must point exclusively to in-kernel virtual addresses. msg.msg_flags may be given MSG_MORE if there will be subsequent data sends for this call. The msg must not specify a destination address, control data or any flags other than MSG_MORE. len is the total amount of data to transmit. (*) Abort a call. void rxrpc_kernel_abort_call(struct rxrpc_call *call, u32 abort_code); This is used to abort a call if it's still in an abortable state. The abort code specified will be placed in the ABORT message sent. (*) Intercept received RxRPC messages. typedef void (*rxrpc_interceptor_t)(struct sock *sk, unsigned long user_call_ID, struct sk_buff *skb); void rxrpc_kernel_intercept_rx_messages(struct socket *sock, rxrpc_interceptor_t interceptor); This installs an interceptor function on the specified AF_RXRPC socket. All messages that would otherwise wind up in the socket's Rx queue are then diverted to this function. Note that care must be taken to process the messages in the right order to maintain DATA message sequentiality. The interceptor function itself is provided with the address of the socket and handling the incoming message, the ID assigned by the kernel utility to the call and the socket buffer containing the message. The skb->mark field indicates the type of message: MARK MEANING =============================== ======================================= RXRPC_SKB_MARK_DATA Data message RXRPC_SKB_MARK_FINAL_ACK Final ACK received for an incoming call RXRPC_SKB_MARK_BUSY Client call rejected as server busy RXRPC_SKB_MARK_REMOTE_ABORT Call aborted by peer RXRPC_SKB_MARK_NET_ERROR Network error detected RXRPC_SKB_MARK_LOCAL_ERROR Local error encountered RXRPC_SKB_MARK_NEW_CALL New incoming call awaiting acceptance The remote abort message can be probed with rxrpc_kernel_get_abort_code(). The two error messages can be probed with rxrpc_kernel_get_error_number(). A new call can be accepted with rxrpc_kernel_accept_call(). Data messages can have their contents extracted with the usual bunch of socket buffer manipulation functions. A data message can be determined to be the last one in a sequence with rxrpc_kernel_is_data_last(). When a data message has been used up, rxrpc_kernel_data_delivered() should be called on it.. Non-data messages should be handled to rxrpc_kernel_free_skb() to dispose of. It is possible to get extra refs on all types of message for later freeing, but this may pin the state of a call until the message is finally freed. (*) Accept an incoming call. struct rxrpc_call * rxrpc_kernel_accept_call(struct socket *sock, unsigned long user_call_ID); This is used to accept an incoming call and to assign it a call ID. This function is similar to rxrpc_kernel_begin_call() and calls accepted must be ended in the same way. If this function is successful, an opaque reference to the RxRPC call is returned. The caller now holds a reference on this and it must be properly ended. (*) Reject an incoming call. int rxrpc_kernel_reject_call(struct socket *sock); This is used to reject the first incoming call on the socket's queue with a BUSY message. -ENODATA is returned if there were no incoming calls. Other errors may be returned if the call had been aborted (-ECONNABORTED) or had timed out (-ETIME). (*) Record the delivery of a data message and free it. void rxrpc_kernel_data_delivered(struct sk_buff *skb); This is used to record a data message as having been delivered and to update the ACK state for the call. The socket buffer will be freed. (*) Free a message. void rxrpc_kernel_free_skb(struct sk_buff *skb); This is used to free a non-DATA socket buffer intercepted from an AF_RXRPC socket. (*) Determine if a data message is the last one on a call. bool rxrpc_kernel_is_data_last(struct sk_buff *skb); This is used to determine if a socket buffer holds the last data message to be received for a call (true will be returned if it does, false if not). The data message will be part of the reply on a client call and the request on an incoming call. In the latter case there will be more messages, but in the former case there will not. (*) Get the abort code from an abort message. u32 rxrpc_kernel_get_abort_code(struct sk_buff *skb); This is used to extract the abort code from a remote abort message. (*) Get the error number from a local or network error message. int rxrpc_kernel_get_error_number(struct sk_buff *skb); This is used to extract the error number from a message indicating either a local error occurred or a network error occurred. Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-27 05:50:17 +07:00
* - reject the call at the front of the queue
*/
int rxrpc_reject_call(struct rxrpc_sock *rx)
{
struct rxrpc_call *call;
int ret;
_enter("");
ASSERT(!irqs_disabled());
write_lock(&rx->call_lock);
ret = -ENODATA;
rxrpc: Calls shouldn't hold socket refs rxrpc calls shouldn't hold refs on the sock struct. This was done so that the socket wouldn't go away whilst the call was in progress, such that the call could reach the socket's queues. However, we can mark the socket as requiring an RCU release and rely on the RCU read lock. To make this work, we do: (1) rxrpc_release_call() removes the call's call user ID. This is now only called from socket operations and not from the call processor: rxrpc_accept_call() / rxrpc_kernel_accept_call() rxrpc_reject_call() / rxrpc_kernel_reject_call() rxrpc_kernel_end_call() rxrpc_release_calls_on_socket() rxrpc_recvmsg() Though it is also called in the cleanup path of rxrpc_accept_incoming_call() before we assign a user ID. (2) Pass the socket pointer into rxrpc_release_call() rather than getting it from the call so that we can get rid of uninitialised calls. (3) Fix call processor queueing to pass a ref to the work queue and to release that ref at the end of the processor function (or to pass it back to the work queue if we have to requeue). (4) Skip out of the call processor function asap if the call is complete and don't requeue it if the call is complete. (5) Clean up the call immediately that the refcount reaches 0 rather than trying to defer it. Actual deallocation is deferred to RCU, however. (6) Don't hold socket refs for allocated calls. (7) Use the RCU read lock when queueing a message on a socket and treat the call's socket pointer according to RCU rules and check it for NULL. We also need to use the RCU read lock when viewing a call through procfs. (8) Transmit the final ACK/ABORT to a client call in rxrpc_release_call() if this hasn't been done yet so that we can then disconnect the call. Once the call is disconnected, it won't have any access to the connection struct and the UDP socket for the call work processor to be able to send the ACK. Terminal retransmission will be handled by the connection processor. (9) Release all calls immediately on the closing of a socket rather than trying to defer this. Incomplete calls will be aborted. The call refcount model is much simplified. Refs are held on the call by: (1) A socket's user ID tree. (2) A socket's incoming call secureq and acceptq. (3) A kernel service that has a call in progress. (4) A queued call work processor. We have to take care to put any call that we failed to queue. (5) sk_buffs on a socket's receive queue. A future patch will get rid of this. Whilst we're at it, we can do: (1) Get rid of the RXRPC_CALL_EV_RELEASE event. Release is now done entirely from the socket routines and never from the call's processor. (2) Get rid of the RXRPC_CALL_DEAD state. Calls now end in the RXRPC_CALL_COMPLETE state. (3) Get rid of the rxrpc_call::destroyer work item. Calls are now torn down when their refcount reaches 0 and then handed over to RCU for final cleanup. (4) Get rid of the rxrpc_call::deadspan timer. Calls are cleaned up immediately they're finished with and don't hang around. Post-completion retransmission is handled by the connection processor once the call is disconnected. (5) Get rid of the dead call expiry setting as there's no longer a timer to set. (6) rxrpc_destroy_all_calls() can just check that the call list is empty. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-07 15:19:31 +07:00
if (list_empty(&rx->acceptq)) {
write_unlock(&rx->call_lock);
_leave(" = -ENODATA");
return -ENODATA;
}
[AF_RXRPC]: Add an interface to the AF_RXRPC module for the AFS filesystem to use Add an interface to the AF_RXRPC module so that the AFS filesystem module can more easily make use of the services available. AFS still opens a socket but then uses the action functions in lieu of sendmsg() and registers an intercept functions to grab messages before they're queued on the socket Rx queue. This permits AFS (or whatever) to: (1) Avoid the overhead of using the recvmsg() call. (2) Use different keys directly on individual client calls on one socket rather than having to open a whole slew of sockets, one for each key it might want to use. (3) Avoid calling request_key() at the point of issue of a call or opening of a socket. This is done instead by AFS at the point of open(), unlink() or other VFS operation and the key handed through. (4) Request the use of something other than GFP_KERNEL to allocate memory. Furthermore: (*) The socket buffer markings used by RxRPC are made available for AFS so that it can interpret the cooked RxRPC messages itself. (*) rxgen (un)marshalling abort codes are made available. The following documentation for the kernel interface is added to Documentation/networking/rxrpc.txt: ========================= AF_RXRPC KERNEL INTERFACE ========================= The AF_RXRPC module also provides an interface for use by in-kernel utilities such as the AFS filesystem. This permits such a utility to: (1) Use different keys directly on individual client calls on one socket rather than having to open a whole slew of sockets, one for each key it might want to use. (2) Avoid having RxRPC call request_key() at the point of issue of a call or opening of a socket. Instead the utility is responsible for requesting a key at the appropriate point. AFS, for instance, would do this during VFS operations such as open() or unlink(). The key is then handed through when the call is initiated. (3) Request the use of something other than GFP_KERNEL to allocate memory. (4) Avoid the overhead of using the recvmsg() call. RxRPC messages can be intercepted before they get put into the socket Rx queue and the socket buffers manipulated directly. To use the RxRPC facility, a kernel utility must still open an AF_RXRPC socket, bind an addess as appropriate and listen if it's to be a server socket, but then it passes this to the kernel interface functions. The kernel interface functions are as follows: (*) Begin a new client call. struct rxrpc_call * rxrpc_kernel_begin_call(struct socket *sock, struct sockaddr_rxrpc *srx, struct key *key, unsigned long user_call_ID, gfp_t gfp); This allocates the infrastructure to make a new RxRPC call and assigns call and connection numbers. The call will be made on the UDP port that the socket is bound to. The call will go to the destination address of a connected client socket unless an alternative is supplied (srx is non-NULL). If a key is supplied then this will be used to secure the call instead of the key bound to the socket with the RXRPC_SECURITY_KEY sockopt. Calls secured in this way will still share connections if at all possible. The user_call_ID is equivalent to that supplied to sendmsg() in the control data buffer. It is entirely feasible to use this to point to a kernel data structure. If this function is successful, an opaque reference to the RxRPC call is returned. The caller now holds a reference on this and it must be properly ended. (*) End a client call. void rxrpc_kernel_end_call(struct rxrpc_call *call); This is used to end a previously begun call. The user_call_ID is expunged from AF_RXRPC's knowledge and will not be seen again in association with the specified call. (*) Send data through a call. int rxrpc_kernel_send_data(struct rxrpc_call *call, struct msghdr *msg, size_t len); This is used to supply either the request part of a client call or the reply part of a server call. msg.msg_iovlen and msg.msg_iov specify the data buffers to be used. msg_iov may not be NULL and must point exclusively to in-kernel virtual addresses. msg.msg_flags may be given MSG_MORE if there will be subsequent data sends for this call. The msg must not specify a destination address, control data or any flags other than MSG_MORE. len is the total amount of data to transmit. (*) Abort a call. void rxrpc_kernel_abort_call(struct rxrpc_call *call, u32 abort_code); This is used to abort a call if it's still in an abortable state. The abort code specified will be placed in the ABORT message sent. (*) Intercept received RxRPC messages. typedef void (*rxrpc_interceptor_t)(struct sock *sk, unsigned long user_call_ID, struct sk_buff *skb); void rxrpc_kernel_intercept_rx_messages(struct socket *sock, rxrpc_interceptor_t interceptor); This installs an interceptor function on the specified AF_RXRPC socket. All messages that would otherwise wind up in the socket's Rx queue are then diverted to this function. Note that care must be taken to process the messages in the right order to maintain DATA message sequentiality. The interceptor function itself is provided with the address of the socket and handling the incoming message, the ID assigned by the kernel utility to the call and the socket buffer containing the message. The skb->mark field indicates the type of message: MARK MEANING =============================== ======================================= RXRPC_SKB_MARK_DATA Data message RXRPC_SKB_MARK_FINAL_ACK Final ACK received for an incoming call RXRPC_SKB_MARK_BUSY Client call rejected as server busy RXRPC_SKB_MARK_REMOTE_ABORT Call aborted by peer RXRPC_SKB_MARK_NET_ERROR Network error detected RXRPC_SKB_MARK_LOCAL_ERROR Local error encountered RXRPC_SKB_MARK_NEW_CALL New incoming call awaiting acceptance The remote abort message can be probed with rxrpc_kernel_get_abort_code(). The two error messages can be probed with rxrpc_kernel_get_error_number(). A new call can be accepted with rxrpc_kernel_accept_call(). Data messages can have their contents extracted with the usual bunch of socket buffer manipulation functions. A data message can be determined to be the last one in a sequence with rxrpc_kernel_is_data_last(). When a data message has been used up, rxrpc_kernel_data_delivered() should be called on it.. Non-data messages should be handled to rxrpc_kernel_free_skb() to dispose of. It is possible to get extra refs on all types of message for later freeing, but this may pin the state of a call until the message is finally freed. (*) Accept an incoming call. struct rxrpc_call * rxrpc_kernel_accept_call(struct socket *sock, unsigned long user_call_ID); This is used to accept an incoming call and to assign it a call ID. This function is similar to rxrpc_kernel_begin_call() and calls accepted must be ended in the same way. If this function is successful, an opaque reference to the RxRPC call is returned. The caller now holds a reference on this and it must be properly ended. (*) Reject an incoming call. int rxrpc_kernel_reject_call(struct socket *sock); This is used to reject the first incoming call on the socket's queue with a BUSY message. -ENODATA is returned if there were no incoming calls. Other errors may be returned if the call had been aborted (-ECONNABORTED) or had timed out (-ETIME). (*) Record the delivery of a data message and free it. void rxrpc_kernel_data_delivered(struct sk_buff *skb); This is used to record a data message as having been delivered and to update the ACK state for the call. The socket buffer will be freed. (*) Free a message. void rxrpc_kernel_free_skb(struct sk_buff *skb); This is used to free a non-DATA socket buffer intercepted from an AF_RXRPC socket. (*) Determine if a data message is the last one on a call. bool rxrpc_kernel_is_data_last(struct sk_buff *skb); This is used to determine if a socket buffer holds the last data message to be received for a call (true will be returned if it does, false if not). The data message will be part of the reply on a client call and the request on an incoming call. In the latter case there will be more messages, but in the former case there will not. (*) Get the abort code from an abort message. u32 rxrpc_kernel_get_abort_code(struct sk_buff *skb); This is used to extract the abort code from a remote abort message. (*) Get the error number from a local or network error message. int rxrpc_kernel_get_error_number(struct sk_buff *skb); This is used to extract the error number from a message indicating either a local error occurred or a network error occurred. Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-27 05:50:17 +07:00
/* dequeue the first call and check it's still valid */
call = list_entry(rx->acceptq.next, struct rxrpc_call, accept_link);
list_del_init(&call->accept_link);
sk_acceptq_removed(&rx->sk);
rxrpc: Trace rxrpc_call usage Add a trace event for debuging rxrpc_call struct usage. Signed-off-by: David Howells <dhowells@redhat.com>
2016-08-30 15:49:29 +07:00
rxrpc_see_call(call);
[AF_RXRPC]: Add an interface to the AF_RXRPC module for the AFS filesystem to use Add an interface to the AF_RXRPC module so that the AFS filesystem module can more easily make use of the services available. AFS still opens a socket but then uses the action functions in lieu of sendmsg() and registers an intercept functions to grab messages before they're queued on the socket Rx queue. This permits AFS (or whatever) to: (1) Avoid the overhead of using the recvmsg() call. (2) Use different keys directly on individual client calls on one socket rather than having to open a whole slew of sockets, one for each key it might want to use. (3) Avoid calling request_key() at the point of issue of a call or opening of a socket. This is done instead by AFS at the point of open(), unlink() or other VFS operation and the key handed through. (4) Request the use of something other than GFP_KERNEL to allocate memory. Furthermore: (*) The socket buffer markings used by RxRPC are made available for AFS so that it can interpret the cooked RxRPC messages itself. (*) rxgen (un)marshalling abort codes are made available. The following documentation for the kernel interface is added to Documentation/networking/rxrpc.txt: ========================= AF_RXRPC KERNEL INTERFACE ========================= The AF_RXRPC module also provides an interface for use by in-kernel utilities such as the AFS filesystem. This permits such a utility to: (1) Use different keys directly on individual client calls on one socket rather than having to open a whole slew of sockets, one for each key it might want to use. (2) Avoid having RxRPC call request_key() at the point of issue of a call or opening of a socket. Instead the utility is responsible for requesting a key at the appropriate point. AFS, for instance, would do this during VFS operations such as open() or unlink(). The key is then handed through when the call is initiated. (3) Request the use of something other than GFP_KERNEL to allocate memory. (4) Avoid the overhead of using the recvmsg() call. RxRPC messages can be intercepted before they get put into the socket Rx queue and the socket buffers manipulated directly. To use the RxRPC facility, a kernel utility must still open an AF_RXRPC socket, bind an addess as appropriate and listen if it's to be a server socket, but then it passes this to the kernel interface functions. The kernel interface functions are as follows: (*) Begin a new client call. struct rxrpc_call * rxrpc_kernel_begin_call(struct socket *sock, struct sockaddr_rxrpc *srx, struct key *key, unsigned long user_call_ID, gfp_t gfp); This allocates the infrastructure to make a new RxRPC call and assigns call and connection numbers. The call will be made on the UDP port that the socket is bound to. The call will go to the destination address of a connected client socket unless an alternative is supplied (srx is non-NULL). If a key is supplied then this will be used to secure the call instead of the key bound to the socket with the RXRPC_SECURITY_KEY sockopt. Calls secured in this way will still share connections if at all possible. The user_call_ID is equivalent to that supplied to sendmsg() in the control data buffer. It is entirely feasible to use this to point to a kernel data structure. If this function is successful, an opaque reference to the RxRPC call is returned. The caller now holds a reference on this and it must be properly ended. (*) End a client call. void rxrpc_kernel_end_call(struct rxrpc_call *call); This is used to end a previously begun call. The user_call_ID is expunged from AF_RXRPC's knowledge and will not be seen again in association with the specified call. (*) Send data through a call. int rxrpc_kernel_send_data(struct rxrpc_call *call, struct msghdr *msg, size_t len); This is used to supply either the request part of a client call or the reply part of a server call. msg.msg_iovlen and msg.msg_iov specify the data buffers to be used. msg_iov may not be NULL and must point exclusively to in-kernel virtual addresses. msg.msg_flags may be given MSG_MORE if there will be subsequent data sends for this call. The msg must not specify a destination address, control data or any flags other than MSG_MORE. len is the total amount of data to transmit. (*) Abort a call. void rxrpc_kernel_abort_call(struct rxrpc_call *call, u32 abort_code); This is used to abort a call if it's still in an abortable state. The abort code specified will be placed in the ABORT message sent. (*) Intercept received RxRPC messages. typedef void (*rxrpc_interceptor_t)(struct sock *sk, unsigned long user_call_ID, struct sk_buff *skb); void rxrpc_kernel_intercept_rx_messages(struct socket *sock, rxrpc_interceptor_t interceptor); This installs an interceptor function on the specified AF_RXRPC socket. All messages that would otherwise wind up in the socket's Rx queue are then diverted to this function. Note that care must be taken to process the messages in the right order to maintain DATA message sequentiality. The interceptor function itself is provided with the address of the socket and handling the incoming message, the ID assigned by the kernel utility to the call and the socket buffer containing the message. The skb->mark field indicates the type of message: MARK MEANING =============================== ======================================= RXRPC_SKB_MARK_DATA Data message RXRPC_SKB_MARK_FINAL_ACK Final ACK received for an incoming call RXRPC_SKB_MARK_BUSY Client call rejected as server busy RXRPC_SKB_MARK_REMOTE_ABORT Call aborted by peer RXRPC_SKB_MARK_NET_ERROR Network error detected RXRPC_SKB_MARK_LOCAL_ERROR Local error encountered RXRPC_SKB_MARK_NEW_CALL New incoming call awaiting acceptance The remote abort message can be probed with rxrpc_kernel_get_abort_code(). The two error messages can be probed with rxrpc_kernel_get_error_number(). A new call can be accepted with rxrpc_kernel_accept_call(). Data messages can have their contents extracted with the usual bunch of socket buffer manipulation functions. A data message can be determined to be the last one in a sequence with rxrpc_kernel_is_data_last(). When a data message has been used up, rxrpc_kernel_data_delivered() should be called on it.. Non-data messages should be handled to rxrpc_kernel_free_skb() to dispose of. It is possible to get extra refs on all types of message for later freeing, but this may pin the state of a call until the message is finally freed. (*) Accept an incoming call. struct rxrpc_call * rxrpc_kernel_accept_call(struct socket *sock, unsigned long user_call_ID); This is used to accept an incoming call and to assign it a call ID. This function is similar to rxrpc_kernel_begin_call() and calls accepted must be ended in the same way. If this function is successful, an opaque reference to the RxRPC call is returned. The caller now holds a reference on this and it must be properly ended. (*) Reject an incoming call. int rxrpc_kernel_reject_call(struct socket *sock); This is used to reject the first incoming call on the socket's queue with a BUSY message. -ENODATA is returned if there were no incoming calls. Other errors may be returned if the call had been aborted (-ECONNABORTED) or had timed out (-ETIME). (*) Record the delivery of a data message and free it. void rxrpc_kernel_data_delivered(struct sk_buff *skb); This is used to record a data message as having been delivered and to update the ACK state for the call. The socket buffer will be freed. (*) Free a message. void rxrpc_kernel_free_skb(struct sk_buff *skb); This is used to free a non-DATA socket buffer intercepted from an AF_RXRPC socket. (*) Determine if a data message is the last one on a call. bool rxrpc_kernel_is_data_last(struct sk_buff *skb); This is used to determine if a socket buffer holds the last data message to be received for a call (true will be returned if it does, false if not). The data message will be part of the reply on a client call and the request on an incoming call. In the latter case there will be more messages, but in the former case there will not. (*) Get the abort code from an abort message. u32 rxrpc_kernel_get_abort_code(struct sk_buff *skb); This is used to extract the abort code from a remote abort message. (*) Get the error number from a local or network error message. int rxrpc_kernel_get_error_number(struct sk_buff *skb); This is used to extract the error number from a message indicating either a local error occurred or a network error occurred. Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-27 05:50:17 +07:00
write_lock_bh(&call->state_lock);
switch (call->state) {
case RXRPC_CALL_SERVER_ACCEPTING:
rxrpc: Calls should only have one terminal state Condense the terminal states of a call state machine to a single state, plus a separate completion type value. The value is then set, along with error and abort code values, only when the call is transitioned to the completion state. Helpers are provided to simplify this. Signed-off-by: David Howells <dhowells@redhat.com>
2016-08-30 15:49:28 +07:00
__rxrpc_set_call_completion(call, RXRPC_CALL_SERVER_BUSY,
0, ECONNABORTED);
rxrpc: Rename call events to begin RXRPC_CALL_EV_ Rename call event names to begin RXRPC_CALL_EV_ to distinguish them from the flags. Signed-off-by: David Howells <dhowells@redhat.com>
2016-03-04 22:53:46 +07:00
if (test_and_set_bit(RXRPC_CALL_EV_REJECT_BUSY, &call->events))
[AF_RXRPC]: Add an interface to the AF_RXRPC module for the AFS filesystem to use Add an interface to the AF_RXRPC module so that the AFS filesystem module can more easily make use of the services available. AFS still opens a socket but then uses the action functions in lieu of sendmsg() and registers an intercept functions to grab messages before they're queued on the socket Rx queue. This permits AFS (or whatever) to: (1) Avoid the overhead of using the recvmsg() call. (2) Use different keys directly on individual client calls on one socket rather than having to open a whole slew of sockets, one for each key it might want to use. (3) Avoid calling request_key() at the point of issue of a call or opening of a socket. This is done instead by AFS at the point of open(), unlink() or other VFS operation and the key handed through. (4) Request the use of something other than GFP_KERNEL to allocate memory. Furthermore: (*) The socket buffer markings used by RxRPC are made available for AFS so that it can interpret the cooked RxRPC messages itself. (*) rxgen (un)marshalling abort codes are made available. The following documentation for the kernel interface is added to Documentation/networking/rxrpc.txt: ========================= AF_RXRPC KERNEL INTERFACE ========================= The AF_RXRPC module also provides an interface for use by in-kernel utilities such as the AFS filesystem. This permits such a utility to: (1) Use different keys directly on individual client calls on one socket rather than having to open a whole slew of sockets, one for each key it might want to use. (2) Avoid having RxRPC call request_key() at the point of issue of a call or opening of a socket. Instead the utility is responsible for requesting a key at the appropriate point. AFS, for instance, would do this during VFS operations such as open() or unlink(). The key is then handed through when the call is initiated. (3) Request the use of something other than GFP_KERNEL to allocate memory. (4) Avoid the overhead of using the recvmsg() call. RxRPC messages can be intercepted before they get put into the socket Rx queue and the socket buffers manipulated directly. To use the RxRPC facility, a kernel utility must still open an AF_RXRPC socket, bind an addess as appropriate and listen if it's to be a server socket, but then it passes this to the kernel interface functions. The kernel interface functions are as follows: (*) Begin a new client call. struct rxrpc_call * rxrpc_kernel_begin_call(struct socket *sock, struct sockaddr_rxrpc *srx, struct key *key, unsigned long user_call_ID, gfp_t gfp); This allocates the infrastructure to make a new RxRPC call and assigns call and connection numbers. The call will be made on the UDP port that the socket is bound to. The call will go to the destination address of a connected client socket unless an alternative is supplied (srx is non-NULL). If a key is supplied then this will be used to secure the call instead of the key bound to the socket with the RXRPC_SECURITY_KEY sockopt. Calls secured in this way will still share connections if at all possible. The user_call_ID is equivalent to that supplied to sendmsg() in the control data buffer. It is entirely feasible to use this to point to a kernel data structure. If this function is successful, an opaque reference to the RxRPC call is returned. The caller now holds a reference on this and it must be properly ended. (*) End a client call. void rxrpc_kernel_end_call(struct rxrpc_call *call); This is used to end a previously begun call. The user_call_ID is expunged from AF_RXRPC's knowledge and will not be seen again in association with the specified call. (*) Send data through a call. int rxrpc_kernel_send_data(struct rxrpc_call *call, struct msghdr *msg, size_t len); This is used to supply either the request part of a client call or the reply part of a server call. msg.msg_iovlen and msg.msg_iov specify the data buffers to be used. msg_iov may not be NULL and must point exclusively to in-kernel virtual addresses. msg.msg_flags may be given MSG_MORE if there will be subsequent data sends for this call. The msg must not specify a destination address, control data or any flags other than MSG_MORE. len is the total amount of data to transmit. (*) Abort a call. void rxrpc_kernel_abort_call(struct rxrpc_call *call, u32 abort_code); This is used to abort a call if it's still in an abortable state. The abort code specified will be placed in the ABORT message sent. (*) Intercept received RxRPC messages. typedef void (*rxrpc_interceptor_t)(struct sock *sk, unsigned long user_call_ID, struct sk_buff *skb); void rxrpc_kernel_intercept_rx_messages(struct socket *sock, rxrpc_interceptor_t interceptor); This installs an interceptor function on the specified AF_RXRPC socket. All messages that would otherwise wind up in the socket's Rx queue are then diverted to this function. Note that care must be taken to process the messages in the right order to maintain DATA message sequentiality. The interceptor function itself is provided with the address of the socket and handling the incoming message, the ID assigned by the kernel utility to the call and the socket buffer containing the message. The skb->mark field indicates the type of message: MARK MEANING =============================== ======================================= RXRPC_SKB_MARK_DATA Data message RXRPC_SKB_MARK_FINAL_ACK Final ACK received for an incoming call RXRPC_SKB_MARK_BUSY Client call rejected as server busy RXRPC_SKB_MARK_REMOTE_ABORT Call aborted by peer RXRPC_SKB_MARK_NET_ERROR Network error detected RXRPC_SKB_MARK_LOCAL_ERROR Local error encountered RXRPC_SKB_MARK_NEW_CALL New incoming call awaiting acceptance The remote abort message can be probed with rxrpc_kernel_get_abort_code(). The two error messages can be probed with rxrpc_kernel_get_error_number(). A new call can be accepted with rxrpc_kernel_accept_call(). Data messages can have their contents extracted with the usual bunch of socket buffer manipulation functions. A data message can be determined to be the last one in a sequence with rxrpc_kernel_is_data_last(). When a data message has been used up, rxrpc_kernel_data_delivered() should be called on it.. Non-data messages should be handled to rxrpc_kernel_free_skb() to dispose of. It is possible to get extra refs on all types of message for later freeing, but this may pin the state of a call until the message is finally freed. (*) Accept an incoming call. struct rxrpc_call * rxrpc_kernel_accept_call(struct socket *sock, unsigned long user_call_ID); This is used to accept an incoming call and to assign it a call ID. This function is similar to rxrpc_kernel_begin_call() and calls accepted must be ended in the same way. If this function is successful, an opaque reference to the RxRPC call is returned. The caller now holds a reference on this and it must be properly ended. (*) Reject an incoming call. int rxrpc_kernel_reject_call(struct socket *sock); This is used to reject the first incoming call on the socket's queue with a BUSY message. -ENODATA is returned if there were no incoming calls. Other errors may be returned if the call had been aborted (-ECONNABORTED) or had timed out (-ETIME). (*) Record the delivery of a data message and free it. void rxrpc_kernel_data_delivered(struct sk_buff *skb); This is used to record a data message as having been delivered and to update the ACK state for the call. The socket buffer will be freed. (*) Free a message. void rxrpc_kernel_free_skb(struct sk_buff *skb); This is used to free a non-DATA socket buffer intercepted from an AF_RXRPC socket. (*) Determine if a data message is the last one on a call. bool rxrpc_kernel_is_data_last(struct sk_buff *skb); This is used to determine if a socket buffer holds the last data message to be received for a call (true will be returned if it does, false if not). The data message will be part of the reply on a client call and the request on an incoming call. In the latter case there will be more messages, but in the former case there will not. (*) Get the abort code from an abort message. u32 rxrpc_kernel_get_abort_code(struct sk_buff *skb); This is used to extract the abort code from a remote abort message. (*) Get the error number from a local or network error message. int rxrpc_kernel_get_error_number(struct sk_buff *skb); This is used to extract the error number from a message indicating either a local error occurred or a network error occurred. Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-27 05:50:17 +07:00
rxrpc_queue_call(call);
ret = 0;
rxrpc: Calls shouldn't hold socket refs rxrpc calls shouldn't hold refs on the sock struct. This was done so that the socket wouldn't go away whilst the call was in progress, such that the call could reach the socket's queues. However, we can mark the socket as requiring an RCU release and rely on the RCU read lock. To make this work, we do: (1) rxrpc_release_call() removes the call's call user ID. This is now only called from socket operations and not from the call processor: rxrpc_accept_call() / rxrpc_kernel_accept_call() rxrpc_reject_call() / rxrpc_kernel_reject_call() rxrpc_kernel_end_call() rxrpc_release_calls_on_socket() rxrpc_recvmsg() Though it is also called in the cleanup path of rxrpc_accept_incoming_call() before we assign a user ID. (2) Pass the socket pointer into rxrpc_release_call() rather than getting it from the call so that we can get rid of uninitialised calls. (3) Fix call processor queueing to pass a ref to the work queue and to release that ref at the end of the processor function (or to pass it back to the work queue if we have to requeue). (4) Skip out of the call processor function asap if the call is complete and don't requeue it if the call is complete. (5) Clean up the call immediately that the refcount reaches 0 rather than trying to defer it. Actual deallocation is deferred to RCU, however. (6) Don't hold socket refs for allocated calls. (7) Use the RCU read lock when queueing a message on a socket and treat the call's socket pointer according to RCU rules and check it for NULL. We also need to use the RCU read lock when viewing a call through procfs. (8) Transmit the final ACK/ABORT to a client call in rxrpc_release_call() if this hasn't been done yet so that we can then disconnect the call. Once the call is disconnected, it won't have any access to the connection struct and the UDP socket for the call work processor to be able to send the ACK. Terminal retransmission will be handled by the connection processor. (9) Release all calls immediately on the closing of a socket rather than trying to defer this. Incomplete calls will be aborted. The call refcount model is much simplified. Refs are held on the call by: (1) A socket's user ID tree. (2) A socket's incoming call secureq and acceptq. (3) A kernel service that has a call in progress. (4) A queued call work processor. We have to take care to put any call that we failed to queue. (5) sk_buffs on a socket's receive queue. A future patch will get rid of this. Whilst we're at it, we can do: (1) Get rid of the RXRPC_CALL_EV_RELEASE event. Release is now done entirely from the socket routines and never from the call's processor. (2) Get rid of the RXRPC_CALL_DEAD state. Calls now end in the RXRPC_CALL_COMPLETE state. (3) Get rid of the rxrpc_call::destroyer work item. Calls are now torn down when their refcount reaches 0 and then handed over to RCU for final cleanup. (4) Get rid of the rxrpc_call::deadspan timer. Calls are cleaned up immediately they're finished with and don't hang around. Post-completion retransmission is handled by the connection processor once the call is disconnected. (5) Get rid of the dead call expiry setting as there's no longer a timer to set. (6) rxrpc_destroy_all_calls() can just check that the call list is empty. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-07 15:19:31 +07:00
break;
rxrpc: Calls should only have one terminal state Condense the terminal states of a call state machine to a single state, plus a separate completion type value. The value is then set, along with error and abort code values, only when the call is transitioned to the completion state. Helpers are provided to simplify this. Signed-off-by: David Howells <dhowells@redhat.com>
2016-08-30 15:49:28 +07:00
case RXRPC_CALL_COMPLETE:
ret = call->error;
rxrpc: Calls shouldn't hold socket refs rxrpc calls shouldn't hold refs on the sock struct. This was done so that the socket wouldn't go away whilst the call was in progress, such that the call could reach the socket's queues. However, we can mark the socket as requiring an RCU release and rely on the RCU read lock. To make this work, we do: (1) rxrpc_release_call() removes the call's call user ID. This is now only called from socket operations and not from the call processor: rxrpc_accept_call() / rxrpc_kernel_accept_call() rxrpc_reject_call() / rxrpc_kernel_reject_call() rxrpc_kernel_end_call() rxrpc_release_calls_on_socket() rxrpc_recvmsg() Though it is also called in the cleanup path of rxrpc_accept_incoming_call() before we assign a user ID. (2) Pass the socket pointer into rxrpc_release_call() rather than getting it from the call so that we can get rid of uninitialised calls. (3) Fix call processor queueing to pass a ref to the work queue and to release that ref at the end of the processor function (or to pass it back to the work queue if we have to requeue). (4) Skip out of the call processor function asap if the call is complete and don't requeue it if the call is complete. (5) Clean up the call immediately that the refcount reaches 0 rather than trying to defer it. Actual deallocation is deferred to RCU, however. (6) Don't hold socket refs for allocated calls. (7) Use the RCU read lock when queueing a message on a socket and treat the call's socket pointer according to RCU rules and check it for NULL. We also need to use the RCU read lock when viewing a call through procfs. (8) Transmit the final ACK/ABORT to a client call in rxrpc_release_call() if this hasn't been done yet so that we can then disconnect the call. Once the call is disconnected, it won't have any access to the connection struct and the UDP socket for the call work processor to be able to send the ACK. Terminal retransmission will be handled by the connection processor. (9) Release all calls immediately on the closing of a socket rather than trying to defer this. Incomplete calls will be aborted. The call refcount model is much simplified. Refs are held on the call by: (1) A socket's user ID tree. (2) A socket's incoming call secureq and acceptq. (3) A kernel service that has a call in progress. (4) A queued call work processor. We have to take care to put any call that we failed to queue. (5) sk_buffs on a socket's receive queue. A future patch will get rid of this. Whilst we're at it, we can do: (1) Get rid of the RXRPC_CALL_EV_RELEASE event. Release is now done entirely from the socket routines and never from the call's processor. (2) Get rid of the RXRPC_CALL_DEAD state. Calls now end in the RXRPC_CALL_COMPLETE state. (3) Get rid of the rxrpc_call::destroyer work item. Calls are now torn down when their refcount reaches 0 and then handed over to RCU for final cleanup. (4) Get rid of the rxrpc_call::deadspan timer. Calls are cleaned up immediately they're finished with and don't hang around. Post-completion retransmission is handled by the connection processor once the call is disconnected. (5) Get rid of the dead call expiry setting as there's no longer a timer to set. (6) rxrpc_destroy_all_calls() can just check that the call list is empty. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-07 15:19:31 +07:00
break;
[AF_RXRPC]: Add an interface to the AF_RXRPC module for the AFS filesystem to use Add an interface to the AF_RXRPC module so that the AFS filesystem module can more easily make use of the services available. AFS still opens a socket but then uses the action functions in lieu of sendmsg() and registers an intercept functions to grab messages before they're queued on the socket Rx queue. This permits AFS (or whatever) to: (1) Avoid the overhead of using the recvmsg() call. (2) Use different keys directly on individual client calls on one socket rather than having to open a whole slew of sockets, one for each key it might want to use. (3) Avoid calling request_key() at the point of issue of a call or opening of a socket. This is done instead by AFS at the point of open(), unlink() or other VFS operation and the key handed through. (4) Request the use of something other than GFP_KERNEL to allocate memory. Furthermore: (*) The socket buffer markings used by RxRPC are made available for AFS so that it can interpret the cooked RxRPC messages itself. (*) rxgen (un)marshalling abort codes are made available. The following documentation for the kernel interface is added to Documentation/networking/rxrpc.txt: ========================= AF_RXRPC KERNEL INTERFACE ========================= The AF_RXRPC module also provides an interface for use by in-kernel utilities such as the AFS filesystem. This permits such a utility to: (1) Use different keys directly on individual client calls on one socket rather than having to open a whole slew of sockets, one for each key it might want to use. (2) Avoid having RxRPC call request_key() at the point of issue of a call or opening of a socket. Instead the utility is responsible for requesting a key at the appropriate point. AFS, for instance, would do this during VFS operations such as open() or unlink(). The key is then handed through when the call is initiated. (3) Request the use of something other than GFP_KERNEL to allocate memory. (4) Avoid the overhead of using the recvmsg() call. RxRPC messages can be intercepted before they get put into the socket Rx queue and the socket buffers manipulated directly. To use the RxRPC facility, a kernel utility must still open an AF_RXRPC socket, bind an addess as appropriate and listen if it's to be a server socket, but then it passes this to the kernel interface functions. The kernel interface functions are as follows: (*) Begin a new client call. struct rxrpc_call * rxrpc_kernel_begin_call(struct socket *sock, struct sockaddr_rxrpc *srx, struct key *key, unsigned long user_call_ID, gfp_t gfp); This allocates the infrastructure to make a new RxRPC call and assigns call and connection numbers. The call will be made on the UDP port that the socket is bound to. The call will go to the destination address of a connected client socket unless an alternative is supplied (srx is non-NULL). If a key is supplied then this will be used to secure the call instead of the key bound to the socket with the RXRPC_SECURITY_KEY sockopt. Calls secured in this way will still share connections if at all possible. The user_call_ID is equivalent to that supplied to sendmsg() in the control data buffer. It is entirely feasible to use this to point to a kernel data structure. If this function is successful, an opaque reference to the RxRPC call is returned. The caller now holds a reference on this and it must be properly ended. (*) End a client call. void rxrpc_kernel_end_call(struct rxrpc_call *call); This is used to end a previously begun call. The user_call_ID is expunged from AF_RXRPC's knowledge and will not be seen again in association with the specified call. (*) Send data through a call. int rxrpc_kernel_send_data(struct rxrpc_call *call, struct msghdr *msg, size_t len); This is used to supply either the request part of a client call or the reply part of a server call. msg.msg_iovlen and msg.msg_iov specify the data buffers to be used. msg_iov may not be NULL and must point exclusively to in-kernel virtual addresses. msg.msg_flags may be given MSG_MORE if there will be subsequent data sends for this call. The msg must not specify a destination address, control data or any flags other than MSG_MORE. len is the total amount of data to transmit. (*) Abort a call. void rxrpc_kernel_abort_call(struct rxrpc_call *call, u32 abort_code); This is used to abort a call if it's still in an abortable state. The abort code specified will be placed in the ABORT message sent. (*) Intercept received RxRPC messages. typedef void (*rxrpc_interceptor_t)(struct sock *sk, unsigned long user_call_ID, struct sk_buff *skb); void rxrpc_kernel_intercept_rx_messages(struct socket *sock, rxrpc_interceptor_t interceptor); This installs an interceptor function on the specified AF_RXRPC socket. All messages that would otherwise wind up in the socket's Rx queue are then diverted to this function. Note that care must be taken to process the messages in the right order to maintain DATA message sequentiality. The interceptor function itself is provided with the address of the socket and handling the incoming message, the ID assigned by the kernel utility to the call and the socket buffer containing the message. The skb->mark field indicates the type of message: MARK MEANING =============================== ======================================= RXRPC_SKB_MARK_DATA Data message RXRPC_SKB_MARK_FINAL_ACK Final ACK received for an incoming call RXRPC_SKB_MARK_BUSY Client call rejected as server busy RXRPC_SKB_MARK_REMOTE_ABORT Call aborted by peer RXRPC_SKB_MARK_NET_ERROR Network error detected RXRPC_SKB_MARK_LOCAL_ERROR Local error encountered RXRPC_SKB_MARK_NEW_CALL New incoming call awaiting acceptance The remote abort message can be probed with rxrpc_kernel_get_abort_code(). The two error messages can be probed with rxrpc_kernel_get_error_number(). A new call can be accepted with rxrpc_kernel_accept_call(). Data messages can have their contents extracted with the usual bunch of socket buffer manipulation functions. A data message can be determined to be the last one in a sequence with rxrpc_kernel_is_data_last(). When a data message has been used up, rxrpc_kernel_data_delivered() should be called on it.. Non-data messages should be handled to rxrpc_kernel_free_skb() to dispose of. It is possible to get extra refs on all types of message for later freeing, but this may pin the state of a call until the message is finally freed. (*) Accept an incoming call. struct rxrpc_call * rxrpc_kernel_accept_call(struct socket *sock, unsigned long user_call_ID); This is used to accept an incoming call and to assign it a call ID. This function is similar to rxrpc_kernel_begin_call() and calls accepted must be ended in the same way. If this function is successful, an opaque reference to the RxRPC call is returned. The caller now holds a reference on this and it must be properly ended. (*) Reject an incoming call. int rxrpc_kernel_reject_call(struct socket *sock); This is used to reject the first incoming call on the socket's queue with a BUSY message. -ENODATA is returned if there were no incoming calls. Other errors may be returned if the call had been aborted (-ECONNABORTED) or had timed out (-ETIME). (*) Record the delivery of a data message and free it. void rxrpc_kernel_data_delivered(struct sk_buff *skb); This is used to record a data message as having been delivered and to update the ACK state for the call. The socket buffer will be freed. (*) Free a message. void rxrpc_kernel_free_skb(struct sk_buff *skb); This is used to free a non-DATA socket buffer intercepted from an AF_RXRPC socket. (*) Determine if a data message is the last one on a call. bool rxrpc_kernel_is_data_last(struct sk_buff *skb); This is used to determine if a socket buffer holds the last data message to be received for a call (true will be returned if it does, false if not). The data message will be part of the reply on a client call and the request on an incoming call. In the latter case there will be more messages, but in the former case there will not. (*) Get the abort code from an abort message. u32 rxrpc_kernel_get_abort_code(struct sk_buff *skb); This is used to extract the abort code from a remote abort message. (*) Get the error number from a local or network error message. int rxrpc_kernel_get_error_number(struct sk_buff *skb); This is used to extract the error number from a message indicating either a local error occurred or a network error occurred. Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-27 05:50:17 +07:00
default:
BUG();
}
[AF_RXRPC]: Provide secure RxRPC sockets for use by userspace and kernel both Provide AF_RXRPC sockets that can be used to talk to AFS servers, or serve answers to AFS clients. KerberosIV security is fully supported. The patches and some example test programs can be found in: http://people.redhat.com/~dhowells/rxrpc/ This will eventually replace the old implementation of kernel-only RxRPC currently resident in net/rxrpc/. Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-27 05:48:28 +07:00
write_unlock_bh(&call->state_lock);
write_unlock(&rx->call_lock);
rxrpc: Calls shouldn't hold socket refs rxrpc calls shouldn't hold refs on the sock struct. This was done so that the socket wouldn't go away whilst the call was in progress, such that the call could reach the socket's queues. However, we can mark the socket as requiring an RCU release and rely on the RCU read lock. To make this work, we do: (1) rxrpc_release_call() removes the call's call user ID. This is now only called from socket operations and not from the call processor: rxrpc_accept_call() / rxrpc_kernel_accept_call() rxrpc_reject_call() / rxrpc_kernel_reject_call() rxrpc_kernel_end_call() rxrpc_release_calls_on_socket() rxrpc_recvmsg() Though it is also called in the cleanup path of rxrpc_accept_incoming_call() before we assign a user ID. (2) Pass the socket pointer into rxrpc_release_call() rather than getting it from the call so that we can get rid of uninitialised calls. (3) Fix call processor queueing to pass a ref to the work queue and to release that ref at the end of the processor function (or to pass it back to the work queue if we have to requeue). (4) Skip out of the call processor function asap if the call is complete and don't requeue it if the call is complete. (5) Clean up the call immediately that the refcount reaches 0 rather than trying to defer it. Actual deallocation is deferred to RCU, however. (6) Don't hold socket refs for allocated calls. (7) Use the RCU read lock when queueing a message on a socket and treat the call's socket pointer according to RCU rules and check it for NULL. We also need to use the RCU read lock when viewing a call through procfs. (8) Transmit the final ACK/ABORT to a client call in rxrpc_release_call() if this hasn't been done yet so that we can then disconnect the call. Once the call is disconnected, it won't have any access to the connection struct and the UDP socket for the call work processor to be able to send the ACK. Terminal retransmission will be handled by the connection processor. (9) Release all calls immediately on the closing of a socket rather than trying to defer this. Incomplete calls will be aborted. The call refcount model is much simplified. Refs are held on the call by: (1) A socket's user ID tree. (2) A socket's incoming call secureq and acceptq. (3) A kernel service that has a call in progress. (4) A queued call work processor. We have to take care to put any call that we failed to queue. (5) sk_buffs on a socket's receive queue. A future patch will get rid of this. Whilst we're at it, we can do: (1) Get rid of the RXRPC_CALL_EV_RELEASE event. Release is now done entirely from the socket routines and never from the call's processor. (2) Get rid of the RXRPC_CALL_DEAD state. Calls now end in the RXRPC_CALL_COMPLETE state. (3) Get rid of the rxrpc_call::destroyer work item. Calls are now torn down when their refcount reaches 0 and then handed over to RCU for final cleanup. (4) Get rid of the rxrpc_call::deadspan timer. Calls are cleaned up immediately they're finished with and don't hang around. Post-completion retransmission is handled by the connection processor once the call is disconnected. (5) Get rid of the dead call expiry setting as there's no longer a timer to set. (6) rxrpc_destroy_all_calls() can just check that the call list is empty. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-07 15:19:31 +07:00
rxrpc_release_call(rx, call);
[AF_RXRPC]: Provide secure RxRPC sockets for use by userspace and kernel both Provide AF_RXRPC sockets that can be used to talk to AFS servers, or serve answers to AFS clients. KerberosIV security is fully supported. The patches and some example test programs can be found in: http://people.redhat.com/~dhowells/rxrpc/ This will eventually replace the old implementation of kernel-only RxRPC currently resident in net/rxrpc/. Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-27 05:48:28 +07:00
_leave(" = %d", ret);
return ret;
}
[AF_RXRPC]: Add an interface to the AF_RXRPC module for the AFS filesystem to use Add an interface to the AF_RXRPC module so that the AFS filesystem module can more easily make use of the services available. AFS still opens a socket but then uses the action functions in lieu of sendmsg() and registers an intercept functions to grab messages before they're queued on the socket Rx queue. This permits AFS (or whatever) to: (1) Avoid the overhead of using the recvmsg() call. (2) Use different keys directly on individual client calls on one socket rather than having to open a whole slew of sockets, one for each key it might want to use. (3) Avoid calling request_key() at the point of issue of a call or opening of a socket. This is done instead by AFS at the point of open(), unlink() or other VFS operation and the key handed through. (4) Request the use of something other than GFP_KERNEL to allocate memory. Furthermore: (*) The socket buffer markings used by RxRPC are made available for AFS so that it can interpret the cooked RxRPC messages itself. (*) rxgen (un)marshalling abort codes are made available. The following documentation for the kernel interface is added to Documentation/networking/rxrpc.txt: ========================= AF_RXRPC KERNEL INTERFACE ========================= The AF_RXRPC module also provides an interface for use by in-kernel utilities such as the AFS filesystem. This permits such a utility to: (1) Use different keys directly on individual client calls on one socket rather than having to open a whole slew of sockets, one for each key it might want to use. (2) Avoid having RxRPC call request_key() at the point of issue of a call or opening of a socket. Instead the utility is responsible for requesting a key at the appropriate point. AFS, for instance, would do this during VFS operations such as open() or unlink(). The key is then handed through when the call is initiated. (3) Request the use of something other than GFP_KERNEL to allocate memory. (4) Avoid the overhead of using the recvmsg() call. RxRPC messages can be intercepted before they get put into the socket Rx queue and the socket buffers manipulated directly. To use the RxRPC facility, a kernel utility must still open an AF_RXRPC socket, bind an addess as appropriate and listen if it's to be a server socket, but then it passes this to the kernel interface functions. The kernel interface functions are as follows: (*) Begin a new client call. struct rxrpc_call * rxrpc_kernel_begin_call(struct socket *sock, struct sockaddr_rxrpc *srx, struct key *key, unsigned long user_call_ID, gfp_t gfp); This allocates the infrastructure to make a new RxRPC call and assigns call and connection numbers. The call will be made on the UDP port that the socket is bound to. The call will go to the destination address of a connected client socket unless an alternative is supplied (srx is non-NULL). If a key is supplied then this will be used to secure the call instead of the key bound to the socket with the RXRPC_SECURITY_KEY sockopt. Calls secured in this way will still share connections if at all possible. The user_call_ID is equivalent to that supplied to sendmsg() in the control data buffer. It is entirely feasible to use this to point to a kernel data structure. If this function is successful, an opaque reference to the RxRPC call is returned. The caller now holds a reference on this and it must be properly ended. (*) End a client call. void rxrpc_kernel_end_call(struct rxrpc_call *call); This is used to end a previously begun call. The user_call_ID is expunged from AF_RXRPC's knowledge and will not be seen again in association with the specified call. (*) Send data through a call. int rxrpc_kernel_send_data(struct rxrpc_call *call, struct msghdr *msg, size_t len); This is used to supply either the request part of a client call or the reply part of a server call. msg.msg_iovlen and msg.msg_iov specify the data buffers to be used. msg_iov may not be NULL and must point exclusively to in-kernel virtual addresses. msg.msg_flags may be given MSG_MORE if there will be subsequent data sends for this call. The msg must not specify a destination address, control data or any flags other than MSG_MORE. len is the total amount of data to transmit. (*) Abort a call. void rxrpc_kernel_abort_call(struct rxrpc_call *call, u32 abort_code); This is used to abort a call if it's still in an abortable state. The abort code specified will be placed in the ABORT message sent. (*) Intercept received RxRPC messages. typedef void (*rxrpc_interceptor_t)(struct sock *sk, unsigned long user_call_ID, struct sk_buff *skb); void rxrpc_kernel_intercept_rx_messages(struct socket *sock, rxrpc_interceptor_t interceptor); This installs an interceptor function on the specified AF_RXRPC socket. All messages that would otherwise wind up in the socket's Rx queue are then diverted to this function. Note that care must be taken to process the messages in the right order to maintain DATA message sequentiality. The interceptor function itself is provided with the address of the socket and handling the incoming message, the ID assigned by the kernel utility to the call and the socket buffer containing the message. The skb->mark field indicates the type of message: MARK MEANING =============================== ======================================= RXRPC_SKB_MARK_DATA Data message RXRPC_SKB_MARK_FINAL_ACK Final ACK received for an incoming call RXRPC_SKB_MARK_BUSY Client call rejected as server busy RXRPC_SKB_MARK_REMOTE_ABORT Call aborted by peer RXRPC_SKB_MARK_NET_ERROR Network error detected RXRPC_SKB_MARK_LOCAL_ERROR Local error encountered RXRPC_SKB_MARK_NEW_CALL New incoming call awaiting acceptance The remote abort message can be probed with rxrpc_kernel_get_abort_code(). The two error messages can be probed with rxrpc_kernel_get_error_number(). A new call can be accepted with rxrpc_kernel_accept_call(). Data messages can have their contents extracted with the usual bunch of socket buffer manipulation functions. A data message can be determined to be the last one in a sequence with rxrpc_kernel_is_data_last(). When a data message has been used up, rxrpc_kernel_data_delivered() should be called on it.. Non-data messages should be handled to rxrpc_kernel_free_skb() to dispose of. It is possible to get extra refs on all types of message for later freeing, but this may pin the state of a call until the message is finally freed. (*) Accept an incoming call. struct rxrpc_call * rxrpc_kernel_accept_call(struct socket *sock, unsigned long user_call_ID); This is used to accept an incoming call and to assign it a call ID. This function is similar to rxrpc_kernel_begin_call() and calls accepted must be ended in the same way. If this function is successful, an opaque reference to the RxRPC call is returned. The caller now holds a reference on this and it must be properly ended. (*) Reject an incoming call. int rxrpc_kernel_reject_call(struct socket *sock); This is used to reject the first incoming call on the socket's queue with a BUSY message. -ENODATA is returned if there were no incoming calls. Other errors may be returned if the call had been aborted (-ECONNABORTED) or had timed out (-ETIME). (*) Record the delivery of a data message and free it. void rxrpc_kernel_data_delivered(struct sk_buff *skb); This is used to record a data message as having been delivered and to update the ACK state for the call. The socket buffer will be freed. (*) Free a message. void rxrpc_kernel_free_skb(struct sk_buff *skb); This is used to free a non-DATA socket buffer intercepted from an AF_RXRPC socket. (*) Determine if a data message is the last one on a call. bool rxrpc_kernel_is_data_last(struct sk_buff *skb); This is used to determine if a socket buffer holds the last data message to be received for a call (true will be returned if it does, false if not). The data message will be part of the reply on a client call and the request on an incoming call. In the latter case there will be more messages, but in the former case there will not. (*) Get the abort code from an abort message. u32 rxrpc_kernel_get_abort_code(struct sk_buff *skb); This is used to extract the abort code from a remote abort message. (*) Get the error number from a local or network error message. int rxrpc_kernel_get_error_number(struct sk_buff *skb); This is used to extract the error number from a message indicating either a local error occurred or a network error occurred. Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-27 05:50:17 +07:00
/**
* rxrpc_kernel_accept_call - Allow a kernel service to accept an incoming call
* @sock: The socket on which the impending call is waiting
* @user_call_ID: The tag to attach to the call
rxrpc: Don't expose skbs to in-kernel users [ver #2] Don't expose skbs to in-kernel users, such as the AFS filesystem, but instead provide a notification hook the indicates that a call needs attention and another that indicates that there's a new call to be collected. This makes the following possibilities more achievable: (1) Call refcounting can be made simpler if skbs don't hold refs to calls. (2) skbs referring to non-data events will be able to be freed much sooner rather than being queued for AFS to pick up as rxrpc_kernel_recv_data will be able to consult the call state. (3) We can shortcut the receive phase when a call is remotely aborted because we don't have to go through all the packets to get to the one cancelling the operation. (4) It makes it easier to do encryption/decryption directly between AFS's buffers and sk_buffs. (5) Encryption/decryption can more easily be done in the AFS's thread contexts - usually that of the userspace process that issued a syscall - rather than in one of rxrpc's background threads on a workqueue. (6) AFS will be able to wait synchronously on a call inside AF_RXRPC. To make this work, the following interface function has been added: int rxrpc_kernel_recv_data( struct socket *sock, struct rxrpc_call *call, void *buffer, size_t bufsize, size_t *_offset, bool want_more, u32 *_abort_code); This is the recvmsg equivalent. It allows the caller to find out about the state of a specific call and to transfer received data into a buffer piecemeal. afs_extract_data() and rxrpc_kernel_recv_data() now do all the extraction logic between them. They don't wait synchronously yet because the socket lock needs to be dealt with. Five interface functions have been removed: rxrpc_kernel_is_data_last() rxrpc_kernel_get_abort_code() rxrpc_kernel_get_error_number() rxrpc_kernel_free_skb() rxrpc_kernel_data_consumed() As a temporary hack, sk_buffs going to an in-kernel call are queued on the rxrpc_call struct (->knlrecv_queue) rather than being handed over to the in-kernel user. To process the queue internally, a temporary function, temp_deliver_data() has been added. This will be replaced with common code between the rxrpc_recvmsg() path and the kernel_rxrpc_recv_data() path in a future patch. Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-08-31 02:42:14 +07:00
* @notify_rx: Where to send notifications instead of socket queue
[AF_RXRPC]: Add an interface to the AF_RXRPC module for the AFS filesystem to use Add an interface to the AF_RXRPC module so that the AFS filesystem module can more easily make use of the services available. AFS still opens a socket but then uses the action functions in lieu of sendmsg() and registers an intercept functions to grab messages before they're queued on the socket Rx queue. This permits AFS (or whatever) to: (1) Avoid the overhead of using the recvmsg() call. (2) Use different keys directly on individual client calls on one socket rather than having to open a whole slew of sockets, one for each key it might want to use. (3) Avoid calling request_key() at the point of issue of a call or opening of a socket. This is done instead by AFS at the point of open(), unlink() or other VFS operation and the key handed through. (4) Request the use of something other than GFP_KERNEL to allocate memory. Furthermore: (*) The socket buffer markings used by RxRPC are made available for AFS so that it can interpret the cooked RxRPC messages itself. (*) rxgen (un)marshalling abort codes are made available. The following documentation for the kernel interface is added to Documentation/networking/rxrpc.txt: ========================= AF_RXRPC KERNEL INTERFACE ========================= The AF_RXRPC module also provides an interface for use by in-kernel utilities such as the AFS filesystem. This permits such a utility to: (1) Use different keys directly on individual client calls on one socket rather than having to open a whole slew of sockets, one for each key it might want to use. (2) Avoid having RxRPC call request_key() at the point of issue of a call or opening of a socket. Instead the utility is responsible for requesting a key at the appropriate point. AFS, for instance, would do this during VFS operations such as open() or unlink(). The key is then handed through when the call is initiated. (3) Request the use of something other than GFP_KERNEL to allocate memory. (4) Avoid the overhead of using the recvmsg() call. RxRPC messages can be intercepted before they get put into the socket Rx queue and the socket buffers manipulated directly. To use the RxRPC facility, a kernel utility must still open an AF_RXRPC socket, bind an addess as appropriate and listen if it's to be a server socket, but then it passes this to the kernel interface functions. The kernel interface functions are as follows: (*) Begin a new client call. struct rxrpc_call * rxrpc_kernel_begin_call(struct socket *sock, struct sockaddr_rxrpc *srx, struct key *key, unsigned long user_call_ID, gfp_t gfp); This allocates the infrastructure to make a new RxRPC call and assigns call and connection numbers. The call will be made on the UDP port that the socket is bound to. The call will go to the destination address of a connected client socket unless an alternative is supplied (srx is non-NULL). If a key is supplied then this will be used to secure the call instead of the key bound to the socket with the RXRPC_SECURITY_KEY sockopt. Calls secured in this way will still share connections if at all possible. The user_call_ID is equivalent to that supplied to sendmsg() in the control data buffer. It is entirely feasible to use this to point to a kernel data structure. If this function is successful, an opaque reference to the RxRPC call is returned. The caller now holds a reference on this and it must be properly ended. (*) End a client call. void rxrpc_kernel_end_call(struct rxrpc_call *call); This is used to end a previously begun call. The user_call_ID is expunged from AF_RXRPC's knowledge and will not be seen again in association with the specified call. (*) Send data through a call. int rxrpc_kernel_send_data(struct rxrpc_call *call, struct msghdr *msg, size_t len); This is used to supply either the request part of a client call or the reply part of a server call. msg.msg_iovlen and msg.msg_iov specify the data buffers to be used. msg_iov may not be NULL and must point exclusively to in-kernel virtual addresses. msg.msg_flags may be given MSG_MORE if there will be subsequent data sends for this call. The msg must not specify a destination address, control data or any flags other than MSG_MORE. len is the total amount of data to transmit. (*) Abort a call. void rxrpc_kernel_abort_call(struct rxrpc_call *call, u32 abort_code); This is used to abort a call if it's still in an abortable state. The abort code specified will be placed in the ABORT message sent. (*) Intercept received RxRPC messages. typedef void (*rxrpc_interceptor_t)(struct sock *sk, unsigned long user_call_ID, struct sk_buff *skb); void rxrpc_kernel_intercept_rx_messages(struct socket *sock, rxrpc_interceptor_t interceptor); This installs an interceptor function on the specified AF_RXRPC socket. All messages that would otherwise wind up in the socket's Rx queue are then diverted to this function. Note that care must be taken to process the messages in the right order to maintain DATA message sequentiality. The interceptor function itself is provided with the address of the socket and handling the incoming message, the ID assigned by the kernel utility to the call and the socket buffer containing the message. The skb->mark field indicates the type of message: MARK MEANING =============================== ======================================= RXRPC_SKB_MARK_DATA Data message RXRPC_SKB_MARK_FINAL_ACK Final ACK received for an incoming call RXRPC_SKB_MARK_BUSY Client call rejected as server busy RXRPC_SKB_MARK_REMOTE_ABORT Call aborted by peer RXRPC_SKB_MARK_NET_ERROR Network error detected RXRPC_SKB_MARK_LOCAL_ERROR Local error encountered RXRPC_SKB_MARK_NEW_CALL New incoming call awaiting acceptance The remote abort message can be probed with rxrpc_kernel_get_abort_code(). The two error messages can be probed with rxrpc_kernel_get_error_number(). A new call can be accepted with rxrpc_kernel_accept_call(). Data messages can have their contents extracted with the usual bunch of socket buffer manipulation functions. A data message can be determined to be the last one in a sequence with rxrpc_kernel_is_data_last(). When a data message has been used up, rxrpc_kernel_data_delivered() should be called on it.. Non-data messages should be handled to rxrpc_kernel_free_skb() to dispose of. It is possible to get extra refs on all types of message for later freeing, but this may pin the state of a call until the message is finally freed. (*) Accept an incoming call. struct rxrpc_call * rxrpc_kernel_accept_call(struct socket *sock, unsigned long user_call_ID); This is used to accept an incoming call and to assign it a call ID. This function is similar to rxrpc_kernel_begin_call() and calls accepted must be ended in the same way. If this function is successful, an opaque reference to the RxRPC call is returned. The caller now holds a reference on this and it must be properly ended. (*) Reject an incoming call. int rxrpc_kernel_reject_call(struct socket *sock); This is used to reject the first incoming call on the socket's queue with a BUSY message. -ENODATA is returned if there were no incoming calls. Other errors may be returned if the call had been aborted (-ECONNABORTED) or had timed out (-ETIME). (*) Record the delivery of a data message and free it. void rxrpc_kernel_data_delivered(struct sk_buff *skb); This is used to record a data message as having been delivered and to update the ACK state for the call. The socket buffer will be freed. (*) Free a message. void rxrpc_kernel_free_skb(struct sk_buff *skb); This is used to free a non-DATA socket buffer intercepted from an AF_RXRPC socket. (*) Determine if a data message is the last one on a call. bool rxrpc_kernel_is_data_last(struct sk_buff *skb); This is used to determine if a socket buffer holds the last data message to be received for a call (true will be returned if it does, false if not). The data message will be part of the reply on a client call and the request on an incoming call. In the latter case there will be more messages, but in the former case there will not. (*) Get the abort code from an abort message. u32 rxrpc_kernel_get_abort_code(struct sk_buff *skb); This is used to extract the abort code from a remote abort message. (*) Get the error number from a local or network error message. int rxrpc_kernel_get_error_number(struct sk_buff *skb); This is used to extract the error number from a message indicating either a local error occurred or a network error occurred. Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-27 05:50:17 +07:00
*
* Allow a kernel service to accept an incoming call, assuming the incoming
rxrpc: Don't expose skbs to in-kernel users [ver #2] Don't expose skbs to in-kernel users, such as the AFS filesystem, but instead provide a notification hook the indicates that a call needs attention and another that indicates that there's a new call to be collected. This makes the following possibilities more achievable: (1) Call refcounting can be made simpler if skbs don't hold refs to calls. (2) skbs referring to non-data events will be able to be freed much sooner rather than being queued for AFS to pick up as rxrpc_kernel_recv_data will be able to consult the call state. (3) We can shortcut the receive phase when a call is remotely aborted because we don't have to go through all the packets to get to the one cancelling the operation. (4) It makes it easier to do encryption/decryption directly between AFS's buffers and sk_buffs. (5) Encryption/decryption can more easily be done in the AFS's thread contexts - usually that of the userspace process that issued a syscall - rather than in one of rxrpc's background threads on a workqueue. (6) AFS will be able to wait synchronously on a call inside AF_RXRPC. To make this work, the following interface function has been added: int rxrpc_kernel_recv_data( struct socket *sock, struct rxrpc_call *call, void *buffer, size_t bufsize, size_t *_offset, bool want_more, u32 *_abort_code); This is the recvmsg equivalent. It allows the caller to find out about the state of a specific call and to transfer received data into a buffer piecemeal. afs_extract_data() and rxrpc_kernel_recv_data() now do all the extraction logic between them. They don't wait synchronously yet because the socket lock needs to be dealt with. Five interface functions have been removed: rxrpc_kernel_is_data_last() rxrpc_kernel_get_abort_code() rxrpc_kernel_get_error_number() rxrpc_kernel_free_skb() rxrpc_kernel_data_consumed() As a temporary hack, sk_buffs going to an in-kernel call are queued on the rxrpc_call struct (->knlrecv_queue) rather than being handed over to the in-kernel user. To process the queue internally, a temporary function, temp_deliver_data() has been added. This will be replaced with common code between the rxrpc_recvmsg() path and the kernel_rxrpc_recv_data() path in a future patch. Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-08-31 02:42:14 +07:00
* call is still valid. The caller should immediately trigger their own
* notification as there must be data waiting.
[AF_RXRPC]: Add an interface to the AF_RXRPC module for the AFS filesystem to use Add an interface to the AF_RXRPC module so that the AFS filesystem module can more easily make use of the services available. AFS still opens a socket but then uses the action functions in lieu of sendmsg() and registers an intercept functions to grab messages before they're queued on the socket Rx queue. This permits AFS (or whatever) to: (1) Avoid the overhead of using the recvmsg() call. (2) Use different keys directly on individual client calls on one socket rather than having to open a whole slew of sockets, one for each key it might want to use. (3) Avoid calling request_key() at the point of issue of a call or opening of a socket. This is done instead by AFS at the point of open(), unlink() or other VFS operation and the key handed through. (4) Request the use of something other than GFP_KERNEL to allocate memory. Furthermore: (*) The socket buffer markings used by RxRPC are made available for AFS so that it can interpret the cooked RxRPC messages itself. (*) rxgen (un)marshalling abort codes are made available. The following documentation for the kernel interface is added to Documentation/networking/rxrpc.txt: ========================= AF_RXRPC KERNEL INTERFACE ========================= The AF_RXRPC module also provides an interface for use by in-kernel utilities such as the AFS filesystem. This permits such a utility to: (1) Use different keys directly on individual client calls on one socket rather than having to open a whole slew of sockets, one for each key it might want to use. (2) Avoid having RxRPC call request_key() at the point of issue of a call or opening of a socket. Instead the utility is responsible for requesting a key at the appropriate point. AFS, for instance, would do this during VFS operations such as open() or unlink(). The key is then handed through when the call is initiated. (3) Request the use of something other than GFP_KERNEL to allocate memory. (4) Avoid the overhead of using the recvmsg() call. RxRPC messages can be intercepted before they get put into the socket Rx queue and the socket buffers manipulated directly. To use the RxRPC facility, a kernel utility must still open an AF_RXRPC socket, bind an addess as appropriate and listen if it's to be a server socket, but then it passes this to the kernel interface functions. The kernel interface functions are as follows: (*) Begin a new client call. struct rxrpc_call * rxrpc_kernel_begin_call(struct socket *sock, struct sockaddr_rxrpc *srx, struct key *key, unsigned long user_call_ID, gfp_t gfp); This allocates the infrastructure to make a new RxRPC call and assigns call and connection numbers. The call will be made on the UDP port that the socket is bound to. The call will go to the destination address of a connected client socket unless an alternative is supplied (srx is non-NULL). If a key is supplied then this will be used to secure the call instead of the key bound to the socket with the RXRPC_SECURITY_KEY sockopt. Calls secured in this way will still share connections if at all possible. The user_call_ID is equivalent to that supplied to sendmsg() in the control data buffer. It is entirely feasible to use this to point to a kernel data structure. If this function is successful, an opaque reference to the RxRPC call is returned. The caller now holds a reference on this and it must be properly ended. (*) End a client call. void rxrpc_kernel_end_call(struct rxrpc_call *call); This is used to end a previously begun call. The user_call_ID is expunged from AF_RXRPC's knowledge and will not be seen again in association with the specified call. (*) Send data through a call. int rxrpc_kernel_send_data(struct rxrpc_call *call, struct msghdr *msg, size_t len); This is used to supply either the request part of a client call or the reply part of a server call. msg.msg_iovlen and msg.msg_iov specify the data buffers to be used. msg_iov may not be NULL and must point exclusively to in-kernel virtual addresses. msg.msg_flags may be given MSG_MORE if there will be subsequent data sends for this call. The msg must not specify a destination address, control data or any flags other than MSG_MORE. len is the total amount of data to transmit. (*) Abort a call. void rxrpc_kernel_abort_call(struct rxrpc_call *call, u32 abort_code); This is used to abort a call if it's still in an abortable state. The abort code specified will be placed in the ABORT message sent. (*) Intercept received RxRPC messages. typedef void (*rxrpc_interceptor_t)(struct sock *sk, unsigned long user_call_ID, struct sk_buff *skb); void rxrpc_kernel_intercept_rx_messages(struct socket *sock, rxrpc_interceptor_t interceptor); This installs an interceptor function on the specified AF_RXRPC socket. All messages that would otherwise wind up in the socket's Rx queue are then diverted to this function. Note that care must be taken to process the messages in the right order to maintain DATA message sequentiality. The interceptor function itself is provided with the address of the socket and handling the incoming message, the ID assigned by the kernel utility to the call and the socket buffer containing the message. The skb->mark field indicates the type of message: MARK MEANING =============================== ======================================= RXRPC_SKB_MARK_DATA Data message RXRPC_SKB_MARK_FINAL_ACK Final ACK received for an incoming call RXRPC_SKB_MARK_BUSY Client call rejected as server busy RXRPC_SKB_MARK_REMOTE_ABORT Call aborted by peer RXRPC_SKB_MARK_NET_ERROR Network error detected RXRPC_SKB_MARK_LOCAL_ERROR Local error encountered RXRPC_SKB_MARK_NEW_CALL New incoming call awaiting acceptance The remote abort message can be probed with rxrpc_kernel_get_abort_code(). The two error messages can be probed with rxrpc_kernel_get_error_number(). A new call can be accepted with rxrpc_kernel_accept_call(). Data messages can have their contents extracted with the usual bunch of socket buffer manipulation functions. A data message can be determined to be the last one in a sequence with rxrpc_kernel_is_data_last(). When a data message has been used up, rxrpc_kernel_data_delivered() should be called on it.. Non-data messages should be handled to rxrpc_kernel_free_skb() to dispose of. It is possible to get extra refs on all types of message for later freeing, but this may pin the state of a call until the message is finally freed. (*) Accept an incoming call. struct rxrpc_call * rxrpc_kernel_accept_call(struct socket *sock, unsigned long user_call_ID); This is used to accept an incoming call and to assign it a call ID. This function is similar to rxrpc_kernel_begin_call() and calls accepted must be ended in the same way. If this function is successful, an opaque reference to the RxRPC call is returned. The caller now holds a reference on this and it must be properly ended. (*) Reject an incoming call. int rxrpc_kernel_reject_call(struct socket *sock); This is used to reject the first incoming call on the socket's queue with a BUSY message. -ENODATA is returned if there were no incoming calls. Other errors may be returned if the call had been aborted (-ECONNABORTED) or had timed out (-ETIME). (*) Record the delivery of a data message and free it. void rxrpc_kernel_data_delivered(struct sk_buff *skb); This is used to record a data message as having been delivered and to update the ACK state for the call. The socket buffer will be freed. (*) Free a message. void rxrpc_kernel_free_skb(struct sk_buff *skb); This is used to free a non-DATA socket buffer intercepted from an AF_RXRPC socket. (*) Determine if a data message is the last one on a call. bool rxrpc_kernel_is_data_last(struct sk_buff *skb); This is used to determine if a socket buffer holds the last data message to be received for a call (true will be returned if it does, false if not). The data message will be part of the reply on a client call and the request on an incoming call. In the latter case there will be more messages, but in the former case there will not. (*) Get the abort code from an abort message. u32 rxrpc_kernel_get_abort_code(struct sk_buff *skb); This is used to extract the abort code from a remote abort message. (*) Get the error number from a local or network error message. int rxrpc_kernel_get_error_number(struct sk_buff *skb); This is used to extract the error number from a message indicating either a local error occurred or a network error occurred. Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-27 05:50:17 +07:00
*/
struct rxrpc_call *rxrpc_kernel_accept_call(struct socket *sock,
rxrpc: Don't expose skbs to in-kernel users [ver #2] Don't expose skbs to in-kernel users, such as the AFS filesystem, but instead provide a notification hook the indicates that a call needs attention and another that indicates that there's a new call to be collected. This makes the following possibilities more achievable: (1) Call refcounting can be made simpler if skbs don't hold refs to calls. (2) skbs referring to non-data events will be able to be freed much sooner rather than being queued for AFS to pick up as rxrpc_kernel_recv_data will be able to consult the call state. (3) We can shortcut the receive phase when a call is remotely aborted because we don't have to go through all the packets to get to the one cancelling the operation. (4) It makes it easier to do encryption/decryption directly between AFS's buffers and sk_buffs. (5) Encryption/decryption can more easily be done in the AFS's thread contexts - usually that of the userspace process that issued a syscall - rather than in one of rxrpc's background threads on a workqueue. (6) AFS will be able to wait synchronously on a call inside AF_RXRPC. To make this work, the following interface function has been added: int rxrpc_kernel_recv_data( struct socket *sock, struct rxrpc_call *call, void *buffer, size_t bufsize, size_t *_offset, bool want_more, u32 *_abort_code); This is the recvmsg equivalent. It allows the caller to find out about the state of a specific call and to transfer received data into a buffer piecemeal. afs_extract_data() and rxrpc_kernel_recv_data() now do all the extraction logic between them. They don't wait synchronously yet because the socket lock needs to be dealt with. Five interface functions have been removed: rxrpc_kernel_is_data_last() rxrpc_kernel_get_abort_code() rxrpc_kernel_get_error_number() rxrpc_kernel_free_skb() rxrpc_kernel_data_consumed() As a temporary hack, sk_buffs going to an in-kernel call are queued on the rxrpc_call struct (->knlrecv_queue) rather than being handed over to the in-kernel user. To process the queue internally, a temporary function, temp_deliver_data() has been added. This will be replaced with common code between the rxrpc_recvmsg() path and the kernel_rxrpc_recv_data() path in a future patch. Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-08-31 02:42:14 +07:00
unsigned long user_call_ID,
rxrpc_notify_rx_t notify_rx)
[AF_RXRPC]: Add an interface to the AF_RXRPC module for the AFS filesystem to use Add an interface to the AF_RXRPC module so that the AFS filesystem module can more easily make use of the services available. AFS still opens a socket but then uses the action functions in lieu of sendmsg() and registers an intercept functions to grab messages before they're queued on the socket Rx queue. This permits AFS (or whatever) to: (1) Avoid the overhead of using the recvmsg() call. (2) Use different keys directly on individual client calls on one socket rather than having to open a whole slew of sockets, one for each key it might want to use. (3) Avoid calling request_key() at the point of issue of a call or opening of a socket. This is done instead by AFS at the point of open(), unlink() or other VFS operation and the key handed through. (4) Request the use of something other than GFP_KERNEL to allocate memory. Furthermore: (*) The socket buffer markings used by RxRPC are made available for AFS so that it can interpret the cooked RxRPC messages itself. (*) rxgen (un)marshalling abort codes are made available. The following documentation for the kernel interface is added to Documentation/networking/rxrpc.txt: ========================= AF_RXRPC KERNEL INTERFACE ========================= The AF_RXRPC module also provides an interface for use by in-kernel utilities such as the AFS filesystem. This permits such a utility to: (1) Use different keys directly on individual client calls on one socket rather than having to open a whole slew of sockets, one for each key it might want to use. (2) Avoid having RxRPC call request_key() at the point of issue of a call or opening of a socket. Instead the utility is responsible for requesting a key at the appropriate point. AFS, for instance, would do this during VFS operations such as open() or unlink(). The key is then handed through when the call is initiated. (3) Request the use of something other than GFP_KERNEL to allocate memory. (4) Avoid the overhead of using the recvmsg() call. RxRPC messages can be intercepted before they get put into the socket Rx queue and the socket buffers manipulated directly. To use the RxRPC facility, a kernel utility must still open an AF_RXRPC socket, bind an addess as appropriate and listen if it's to be a server socket, but then it passes this to the kernel interface functions. The kernel interface functions are as follows: (*) Begin a new client call. struct rxrpc_call * rxrpc_kernel_begin_call(struct socket *sock, struct sockaddr_rxrpc *srx, struct key *key, unsigned long user_call_ID, gfp_t gfp); This allocates the infrastructure to make a new RxRPC call and assigns call and connection numbers. The call will be made on the UDP port that the socket is bound to. The call will go to the destination address of a connected client socket unless an alternative is supplied (srx is non-NULL). If a key is supplied then this will be used to secure the call instead of the key bound to the socket with the RXRPC_SECURITY_KEY sockopt. Calls secured in this way will still share connections if at all possible. The user_call_ID is equivalent to that supplied to sendmsg() in the control data buffer. It is entirely feasible to use this to point to a kernel data structure. If this function is successful, an opaque reference to the RxRPC call is returned. The caller now holds a reference on this and it must be properly ended. (*) End a client call. void rxrpc_kernel_end_call(struct rxrpc_call *call); This is used to end a previously begun call. The user_call_ID is expunged from AF_RXRPC's knowledge and will not be seen again in association with the specified call. (*) Send data through a call. int rxrpc_kernel_send_data(struct rxrpc_call *call, struct msghdr *msg, size_t len); This is used to supply either the request part of a client call or the reply part of a server call. msg.msg_iovlen and msg.msg_iov specify the data buffers to be used. msg_iov may not be NULL and must point exclusively to in-kernel virtual addresses. msg.msg_flags may be given MSG_MORE if there will be subsequent data sends for this call. The msg must not specify a destination address, control data or any flags other than MSG_MORE. len is the total amount of data to transmit. (*) Abort a call. void rxrpc_kernel_abort_call(struct rxrpc_call *call, u32 abort_code); This is used to abort a call if it's still in an abortable state. The abort code specified will be placed in the ABORT message sent. (*) Intercept received RxRPC messages. typedef void (*rxrpc_interceptor_t)(struct sock *sk, unsigned long user_call_ID, struct sk_buff *skb); void rxrpc_kernel_intercept_rx_messages(struct socket *sock, rxrpc_interceptor_t interceptor); This installs an interceptor function on the specified AF_RXRPC socket. All messages that would otherwise wind up in the socket's Rx queue are then diverted to this function. Note that care must be taken to process the messages in the right order to maintain DATA message sequentiality. The interceptor function itself is provided with the address of the socket and handling the incoming message, the ID assigned by the kernel utility to the call and the socket buffer containing the message. The skb->mark field indicates the type of message: MARK MEANING =============================== ======================================= RXRPC_SKB_MARK_DATA Data message RXRPC_SKB_MARK_FINAL_ACK Final ACK received for an incoming call RXRPC_SKB_MARK_BUSY Client call rejected as server busy RXRPC_SKB_MARK_REMOTE_ABORT Call aborted by peer RXRPC_SKB_MARK_NET_ERROR Network error detected RXRPC_SKB_MARK_LOCAL_ERROR Local error encountered RXRPC_SKB_MARK_NEW_CALL New incoming call awaiting acceptance The remote abort message can be probed with rxrpc_kernel_get_abort_code(). The two error messages can be probed with rxrpc_kernel_get_error_number(). A new call can be accepted with rxrpc_kernel_accept_call(). Data messages can have their contents extracted with the usual bunch of socket buffer manipulation functions. A data message can be determined to be the last one in a sequence with rxrpc_kernel_is_data_last(). When a data message has been used up, rxrpc_kernel_data_delivered() should be called on it.. Non-data messages should be handled to rxrpc_kernel_free_skb() to dispose of. It is possible to get extra refs on all types of message for later freeing, but this may pin the state of a call until the message is finally freed. (*) Accept an incoming call. struct rxrpc_call * rxrpc_kernel_accept_call(struct socket *sock, unsigned long user_call_ID); This is used to accept an incoming call and to assign it a call ID. This function is similar to rxrpc_kernel_begin_call() and calls accepted must be ended in the same way. If this function is successful, an opaque reference to the RxRPC call is returned. The caller now holds a reference on this and it must be properly ended. (*) Reject an incoming call. int rxrpc_kernel_reject_call(struct socket *sock); This is used to reject the first incoming call on the socket's queue with a BUSY message. -ENODATA is returned if there were no incoming calls. Other errors may be returned if the call had been aborted (-ECONNABORTED) or had timed out (-ETIME). (*) Record the delivery of a data message and free it. void rxrpc_kernel_data_delivered(struct sk_buff *skb); This is used to record a data message as having been delivered and to update the ACK state for the call. The socket buffer will be freed. (*) Free a message. void rxrpc_kernel_free_skb(struct sk_buff *skb); This is used to free a non-DATA socket buffer intercepted from an AF_RXRPC socket. (*) Determine if a data message is the last one on a call. bool rxrpc_kernel_is_data_last(struct sk_buff *skb); This is used to determine if a socket buffer holds the last data message to be received for a call (true will be returned if it does, false if not). The data message will be part of the reply on a client call and the request on an incoming call. In the latter case there will be more messages, but in the former case there will not. (*) Get the abort code from an abort message. u32 rxrpc_kernel_get_abort_code(struct sk_buff *skb); This is used to extract the abort code from a remote abort message. (*) Get the error number from a local or network error message. int rxrpc_kernel_get_error_number(struct sk_buff *skb); This is used to extract the error number from a message indicating either a local error occurred or a network error occurred. Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-27 05:50:17 +07:00
{
struct rxrpc_call *call;
_enter(",%lx", user_call_ID);
rxrpc: Don't expose skbs to in-kernel users [ver #2] Don't expose skbs to in-kernel users, such as the AFS filesystem, but instead provide a notification hook the indicates that a call needs attention and another that indicates that there's a new call to be collected. This makes the following possibilities more achievable: (1) Call refcounting can be made simpler if skbs don't hold refs to calls. (2) skbs referring to non-data events will be able to be freed much sooner rather than being queued for AFS to pick up as rxrpc_kernel_recv_data will be able to consult the call state. (3) We can shortcut the receive phase when a call is remotely aborted because we don't have to go through all the packets to get to the one cancelling the operation. (4) It makes it easier to do encryption/decryption directly between AFS's buffers and sk_buffs. (5) Encryption/decryption can more easily be done in the AFS's thread contexts - usually that of the userspace process that issued a syscall - rather than in one of rxrpc's background threads on a workqueue. (6) AFS will be able to wait synchronously on a call inside AF_RXRPC. To make this work, the following interface function has been added: int rxrpc_kernel_recv_data( struct socket *sock, struct rxrpc_call *call, void *buffer, size_t bufsize, size_t *_offset, bool want_more, u32 *_abort_code); This is the recvmsg equivalent. It allows the caller to find out about the state of a specific call and to transfer received data into a buffer piecemeal. afs_extract_data() and rxrpc_kernel_recv_data() now do all the extraction logic between them. They don't wait synchronously yet because the socket lock needs to be dealt with. Five interface functions have been removed: rxrpc_kernel_is_data_last() rxrpc_kernel_get_abort_code() rxrpc_kernel_get_error_number() rxrpc_kernel_free_skb() rxrpc_kernel_data_consumed() As a temporary hack, sk_buffs going to an in-kernel call are queued on the rxrpc_call struct (->knlrecv_queue) rather than being handed over to the in-kernel user. To process the queue internally, a temporary function, temp_deliver_data() has been added. This will be replaced with common code between the rxrpc_recvmsg() path and the kernel_rxrpc_recv_data() path in a future patch. Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-08-31 02:42:14 +07:00
call = rxrpc_accept_call(rxrpc_sk(sock->sk), user_call_ID, notify_rx);
[AF_RXRPC]: Add an interface to the AF_RXRPC module for the AFS filesystem to use Add an interface to the AF_RXRPC module so that the AFS filesystem module can more easily make use of the services available. AFS still opens a socket but then uses the action functions in lieu of sendmsg() and registers an intercept functions to grab messages before they're queued on the socket Rx queue. This permits AFS (or whatever) to: (1) Avoid the overhead of using the recvmsg() call. (2) Use different keys directly on individual client calls on one socket rather than having to open a whole slew of sockets, one for each key it might want to use. (3) Avoid calling request_key() at the point of issue of a call or opening of a socket. This is done instead by AFS at the point of open(), unlink() or other VFS operation and the key handed through. (4) Request the use of something other than GFP_KERNEL to allocate memory. Furthermore: (*) The socket buffer markings used by RxRPC are made available for AFS so that it can interpret the cooked RxRPC messages itself. (*) rxgen (un)marshalling abort codes are made available. The following documentation for the kernel interface is added to Documentation/networking/rxrpc.txt: ========================= AF_RXRPC KERNEL INTERFACE ========================= The AF_RXRPC module also provides an interface for use by in-kernel utilities such as the AFS filesystem. This permits such a utility to: (1) Use different keys directly on individual client calls on one socket rather than having to open a whole slew of sockets, one for each key it might want to use. (2) Avoid having RxRPC call request_key() at the point of issue of a call or opening of a socket. Instead the utility is responsible for requesting a key at the appropriate point. AFS, for instance, would do this during VFS operations such as open() or unlink(). The key is then handed through when the call is initiated. (3) Request the use of something other than GFP_KERNEL to allocate memory. (4) Avoid the overhead of using the recvmsg() call. RxRPC messages can be intercepted before they get put into the socket Rx queue and the socket buffers manipulated directly. To use the RxRPC facility, a kernel utility must still open an AF_RXRPC socket, bind an addess as appropriate and listen if it's to be a server socket, but then it passes this to the kernel interface functions. The kernel interface functions are as follows: (*) Begin a new client call. struct rxrpc_call * rxrpc_kernel_begin_call(struct socket *sock, struct sockaddr_rxrpc *srx, struct key *key, unsigned long user_call_ID, gfp_t gfp); This allocates the infrastructure to make a new RxRPC call and assigns call and connection numbers. The call will be made on the UDP port that the socket is bound to. The call will go to the destination address of a connected client socket unless an alternative is supplied (srx is non-NULL). If a key is supplied then this will be used to secure the call instead of the key bound to the socket with the RXRPC_SECURITY_KEY sockopt. Calls secured in this way will still share connections if at all possible. The user_call_ID is equivalent to that supplied to sendmsg() in the control data buffer. It is entirely feasible to use this to point to a kernel data structure. If this function is successful, an opaque reference to the RxRPC call is returned. The caller now holds a reference on this and it must be properly ended. (*) End a client call. void rxrpc_kernel_end_call(struct rxrpc_call *call); This is used to end a previously begun call. The user_call_ID is expunged from AF_RXRPC's knowledge and will not be seen again in association with the specified call. (*) Send data through a call. int rxrpc_kernel_send_data(struct rxrpc_call *call, struct msghdr *msg, size_t len); This is used to supply either the request part of a client call or the reply part of a server call. msg.msg_iovlen and msg.msg_iov specify the data buffers to be used. msg_iov may not be NULL and must point exclusively to in-kernel virtual addresses. msg.msg_flags may be given MSG_MORE if there will be subsequent data sends for this call. The msg must not specify a destination address, control data or any flags other than MSG_MORE. len is the total amount of data to transmit. (*) Abort a call. void rxrpc_kernel_abort_call(struct rxrpc_call *call, u32 abort_code); This is used to abort a call if it's still in an abortable state. The abort code specified will be placed in the ABORT message sent. (*) Intercept received RxRPC messages. typedef void (*rxrpc_interceptor_t)(struct sock *sk, unsigned long user_call_ID, struct sk_buff *skb); void rxrpc_kernel_intercept_rx_messages(struct socket *sock, rxrpc_interceptor_t interceptor); This installs an interceptor function on the specified AF_RXRPC socket. All messages that would otherwise wind up in the socket's Rx queue are then diverted to this function. Note that care must be taken to process the messages in the right order to maintain DATA message sequentiality. The interceptor function itself is provided with the address of the socket and handling the incoming message, the ID assigned by the kernel utility to the call and the socket buffer containing the message. The skb->mark field indicates the type of message: MARK MEANING =============================== ======================================= RXRPC_SKB_MARK_DATA Data message RXRPC_SKB_MARK_FINAL_ACK Final ACK received for an incoming call RXRPC_SKB_MARK_BUSY Client call rejected as server busy RXRPC_SKB_MARK_REMOTE_ABORT Call aborted by peer RXRPC_SKB_MARK_NET_ERROR Network error detected RXRPC_SKB_MARK_LOCAL_ERROR Local error encountered RXRPC_SKB_MARK_NEW_CALL New incoming call awaiting acceptance The remote abort message can be probed with rxrpc_kernel_get_abort_code(). The two error messages can be probed with rxrpc_kernel_get_error_number(). A new call can be accepted with rxrpc_kernel_accept_call(). Data messages can have their contents extracted with the usual bunch of socket buffer manipulation functions. A data message can be determined to be the last one in a sequence with rxrpc_kernel_is_data_last(). When a data message has been used up, rxrpc_kernel_data_delivered() should be called on it.. Non-data messages should be handled to rxrpc_kernel_free_skb() to dispose of. It is possible to get extra refs on all types of message for later freeing, but this may pin the state of a call until the message is finally freed. (*) Accept an incoming call. struct rxrpc_call * rxrpc_kernel_accept_call(struct socket *sock, unsigned long user_call_ID); This is used to accept an incoming call and to assign it a call ID. This function is similar to rxrpc_kernel_begin_call() and calls accepted must be ended in the same way. If this function is successful, an opaque reference to the RxRPC call is returned. The caller now holds a reference on this and it must be properly ended. (*) Reject an incoming call. int rxrpc_kernel_reject_call(struct socket *sock); This is used to reject the first incoming call on the socket's queue with a BUSY message. -ENODATA is returned if there were no incoming calls. Other errors may be returned if the call had been aborted (-ECONNABORTED) or had timed out (-ETIME). (*) Record the delivery of a data message and free it. void rxrpc_kernel_data_delivered(struct sk_buff *skb); This is used to record a data message as having been delivered and to update the ACK state for the call. The socket buffer will be freed. (*) Free a message. void rxrpc_kernel_free_skb(struct sk_buff *skb); This is used to free a non-DATA socket buffer intercepted from an AF_RXRPC socket. (*) Determine if a data message is the last one on a call. bool rxrpc_kernel_is_data_last(struct sk_buff *skb); This is used to determine if a socket buffer holds the last data message to be received for a call (true will be returned if it does, false if not). The data message will be part of the reply on a client call and the request on an incoming call. In the latter case there will be more messages, but in the former case there will not. (*) Get the abort code from an abort message. u32 rxrpc_kernel_get_abort_code(struct sk_buff *skb); This is used to extract the abort code from a remote abort message. (*) Get the error number from a local or network error message. int rxrpc_kernel_get_error_number(struct sk_buff *skb); This is used to extract the error number from a message indicating either a local error occurred or a network error occurred. Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-27 05:50:17 +07:00
_leave(" = %p", call);
return call;
}
EXPORT_SYMBOL(rxrpc_kernel_accept_call);
/**
* rxrpc_kernel_reject_call - Allow a kernel service to reject an incoming call
* @sock: The socket on which the impending call is waiting
*
* Allow a kernel service to reject an incoming call with a BUSY message,
* assuming the incoming call is still valid.
*/
int rxrpc_kernel_reject_call(struct socket *sock)
{
int ret;
_enter("");
ret = rxrpc_reject_call(rxrpc_sk(sock->sk));
_leave(" = %d", ret);
return ret;
}
EXPORT_SYMBOL(rxrpc_kernel_reject_call);
rxrpc: Preallocate peers, conns and calls for incoming service requests Make it possible for the data_ready handler called from the UDP transport socket to completely instantiate an rxrpc_call structure and make it immediately live by preallocating all the memory it might need. The idea is to cut out the background thread usage as much as possible. [Note that the preallocated structs are not actually used in this patch - that will be done in a future patch.] If insufficient resources are available in the preallocation buffers, it will be possible to discard the DATA packet in the data_ready handler or schedule a BUSY packet without the need to schedule an attempt at allocation in a background thread. To this end: (1) Preallocate rxrpc_peer, rxrpc_connection and rxrpc_call structs to a maximum number each of the listen backlog size. The backlog size is limited to a maxmimum of 32. Only this many of each can be in the preallocation buffer. (2) For userspace sockets, the preallocation is charged initially by listen() and will be recharged by accepting or rejecting pending new incoming calls. (3) For kernel services {,re,dis}charging of the preallocation buffers is handled manually. Two notifier callbacks have to be provided before kernel_listen() is invoked: (a) An indication that a new call has been instantiated. This can be used to trigger background recharging. (b) An indication that a call is being discarded. This is used when the socket is being released. A function, rxrpc_kernel_charge_accept() is called by the kernel service to preallocate a single call. It should be passed the user ID to be used for that call and a callback to associate the rxrpc call with the kernel service's side of the ID. (4) Discard the preallocation when the socket is closed. (5) Temporarily bump the refcount on the call allocated in rxrpc_incoming_call() so that rxrpc_release_call() can ditch the preallocation ref on service calls unconditionally. This will no longer be necessary once the preallocation is used. Note that this does not yet control the number of active service calls on a client - that will come in a later patch. A future development would be to provide a setsockopt() call that allows a userspace server to manually charge the preallocation buffer. This would allow user call IDs to be provided in advance and the awkward manual accept stage to be bypassed. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-08 17:10:12 +07:00
/*
* rxrpc_kernel_charge_accept - Charge up socket with preallocated calls
* @sock: The socket on which to preallocate
* @notify_rx: Event notification function for the call
* @user_attach_call: Func to attach call to user_call_ID
* @user_call_ID: The tag to attach to the preallocated call
* @gfp: The allocation conditions.
*
* Charge up the socket with preallocated calls, each with a user ID. A
* function should be provided to effect the attachment from the user's side.
* The user is given a ref to hold on the call.
*
* Note that the call may be come connected before this function returns.
*/
int rxrpc_kernel_charge_accept(struct socket *sock,
rxrpc_notify_rx_t notify_rx,
rxrpc_user_attach_call_t user_attach_call,
unsigned long user_call_ID, gfp_t gfp)
{
struct rxrpc_sock *rx = rxrpc_sk(sock->sk);
struct rxrpc_backlog *b = rx->backlog;
if (sock->sk->sk_state == RXRPC_CLOSE)
return -ESHUTDOWN;
return rxrpc_service_prealloc_one(rx, b, notify_rx,
user_attach_call, user_call_ID,
gfp);
}
EXPORT_SYMBOL(rxrpc_kernel_charge_accept);
Reference in New Issue Copy Permalink