The BKL is completely out of the picture in the lockd and sunrpc code
these days. Update the antiquated comments that refer to it.
Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Testing has shown that the pool->sp_lock can be a bottleneck on a busy
server. Every time data is received on a socket, the server must take
that lock in order to dequeue a thread from the sp_threads list.
Address this problem by eliminating the sp_threads list (which contains
threads that are currently idle) and replacing it with a RQ_BUSY flag in
svc_rqst. This allows us to walk the sp_all_threads list under the
rcu_read_lock and find a suitable thread for the xprt by doing a
test_and_set_bit.
Note that we do still have a potential atomicity problem however with
this approach. We don't want svc_xprt_do_enqueue to set the
rqst->rq_xprt pointer unless a test_and_set_bit of RQ_BUSY returned
zero (which indicates that the thread was idle). But, by the time we
check that, the bit could be flipped by a waking thread.
To address this, we acquire a new per-rqst spinlock (rq_lock) and take
that before doing the test_and_set_bit. If that returns false, then we
can set rq_xprt and drop the spinlock. Then, when the thread wakes up,
it must set the bit under the same spinlock and can trust that if it was
already set then the rq_xprt is also properly set.
With this scheme, the case where we have an idle thread no longer needs
to take the highly contended pool->sp_lock at all, and that removes the
bottleneck.
That still leaves one issue: What of the case where we walk the whole
sp_all_threads list and don't find an idle thread? Because the search is
lockess, it's possible for the queueing to race with a thread that is
going to sleep. To address that, we queue the xprt and then search again.
If we find an idle thread at that point, we can't attach the xprt to it
directly since that might race with a different thread waking up and
finding it. All we can do is wake the idle thread back up and let it
attempt to find the now-queued xprt.
Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Tested-by: Chris Worley <chris.worley@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
...also make the manipulation of sp_all_threads list use RCU-friendly
functions.
Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Tested-by: Chris Worley <chris.worley@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Currently all svc_create callers pass in NULL for the shutdown parm,
which then gets fixed up to be svc_rpcb_cleanup if the service uses
rpcbind.
Simplify this by instead having the the only caller that requires it
(lockd) pass in svc_rpcb_cleanup and get rid of the special casing.
Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Highlights include:
Features:
- NFSv4.2 client support for hole punching and preallocation.
- Further RPC/RDMA client improvements.
- Add more RPC transport debugging tracepoints.
- Add RPC debugging tools in debugfs.
Bugfixes:
- Stable fix for layoutget error handling
- Fix a change in COMMIT behaviour resulting from the recent io code updates
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1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=wOP3
-----END PGP SIGNATURE-----
Merge tag 'nfs-for-3.19-1' into nfsd for-3.19 branch
Mainly what I need is 860a0d9e51 "sunrpc: add some tracepoints in
svc_rqst handling functions", which subsequent server rpc patches from
jlayton depend on. I'm merging this later tag on the assumption that's
more likely to be a tested and stable point.
Currently, it leaks when the allocation fails.
Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
It's always set to whatever CONFIG_SUNRPC_DEBUG is, so just use that.
Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
...just around svc_send, svc_recv and svc_process for now.
Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
The m->pool_to[] array has "maxpools" number of elements. It's
allocated in svc_pool_map_alloc_arrays() which we called earlier in the
function. This test should be >= instead of >.
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
We're always _only_ waking up tasks from within the sp_threads list, so
we know that they are enqueued and alive. The rq_wait waitqueue is just
a distraction with extra atomic semantics.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
rq_usedeferral and rq_splice_ok are used as 0 and 1, just defined to bool.
Signed-off-by: Kinglong Mee <kinglongmee@gmail.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
NFSv4 clients can contact port 2049 directly instead of needing the
portmapper.
Therefore a failure to register to the portmapper when starting an
NFSv4-only server isn't really a problem.
But Gareth Williams reports that an attempt to start an NFSv4-only
server without starting portmap fails:
#rpc.nfsd -N 2 -N 3
rpc.nfsd: writing fd to kernel failed: errno 111 (Connection refused)
rpc.nfsd: unable to set any sockets for nfsd
Add a flag to svc_version to tell the rpc layer it can safely ignore an
rpcbind failure in the NFSv4-only case.
Reported-by: Gareth Williams <gareth@garethwilliams.me.uk>
Reviewed-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Kinglong Mee <kinglongmee@gmail.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Calling kthread_run with a single name parameter causes it to be handled
as a format string. Many callers are passing potentially dynamic string
content, so use "%s" in those cases to avoid any potential accidents.
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Rewrite server shutdown to remove the assumption that there are no
longer any threads running (no longer true, for example, when shutting
down the service in one network namespace while it's still running in
others).
Do that by doing what we'd do in normal circumstances: just CLOSE each
socket, then enqueue it.
Since there may not be threads to handle the resulting queued xprts,
also run a simplified version of the svc_recv() loop run by a server to
clean up any closed xprts afterwards.
Cc: stable@kernel.org
Tested-by: Jason Tibbitts <tibbs@math.uh.edu>
Tested-by: Paweł Sikora <pawel.sikora@agmk.net>
Acked-by: Stanislav Kinsbursky <skinsbursky@parallels.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Pull nfsd update from Bruce Fields:
"Included this time:
- more nfsd containerization work from Stanislav Kinsbursky: we're
not quite there yet, but should be by 3.9.
- NFSv4.1 progress: implementation of basic backchannel security
negotiation and the mandatory BACKCHANNEL_CTL operation. See
http://wiki.linux-nfs.org/wiki/index.php/Server_4.0_and_4.1_issues
for remaining TODO's
- Fixes for some bugs that could be triggered by unusual compounds.
Our xdr code wasn't designed with v4 compounds in mind, and it
shows. A more thorough rewrite is still a todo.
- If you've ever seen "RPC: multiple fragments per record not
supported" logged while using some sort of odd userland NFS client,
that should now be fixed.
- Further work from Jeff Layton on our mechanism for storing
information about NFSv4 clients across reboots.
- Further work from Bryan Schumaker on his fault-injection mechanism
(which allows us to discard selective NFSv4 state, to excercise
rarely-taken recovery code paths in the client.)
- The usual mix of miscellaneous bugs and cleanup.
Thanks to everyone who tested or contributed this cycle."
* 'for-3.8' of git://linux-nfs.org/~bfields/linux: (111 commits)
nfsd4: don't leave freed stateid hashed
nfsd4: free_stateid can use the current stateid
nfsd4: cleanup: replace rq_resused count by rq_next_page pointer
nfsd: warn on odd reply state in nfsd_vfs_read
nfsd4: fix oops on unusual readlike compound
nfsd4: disable zero-copy on non-final read ops
svcrpc: fix some printks
NFSD: Correct the size calculation in fault_inject_write
NFSD: Pass correct buffer size to rpc_ntop
nfsd: pass proper net to nfsd_destroy() from NFSd kthreads
nfsd: simplify service shutdown
nfsd: replace boolean nfsd_up flag by users counter
nfsd: simplify NFSv4 state init and shutdown
nfsd: introduce helpers for generic resources init and shutdown
nfsd: make NFSd service structure allocated per net
nfsd: make NFSd service boot time per-net
nfsd: per-net NFSd up flag introduced
nfsd: move per-net startup code to separated function
nfsd: pass net to __write_ports() and down
nfsd: pass net to nfsd_set_nrthreads()
...
Instead of calling BUG_ON(), do a WARN_ON_ONCE() and return -EINVAL.
Signed-off-by: Weston Andros Adamson <dros@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Replace two bounds checking BUG_ON() calls with WARN_ON_ONCE() and resetting
the requested size to RPCSVC_MAXPAGES.
Signed-off-by: Weston Andros Adamson <dros@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Replace BUG_ON() with a WARN() and early return.
Signed-off-by: Weston Andros Adamson <dros@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Highlights include:
- Fix a couple of mount regressions due to the recent cleanups.
- Fix an Oops in the open recovery code
- Fix an rpc_pipefs upcall hang that results from some of the
net namespace work from 3.4.x (stable kernel candidate).
- Fix a couple of write and o_direct regressions that were found
at last weeks Bakeathon testing event in Ann Arbor.
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.4.12 (GNU/Linux)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=unbu
-----END PGP SIGNATURE-----
Merge tag 'nfs-for-3.5-2' of git://git.linux-nfs.org/projects/trondmy/linux-nfs
Pull NFS client bugfixes from Trond Myklebust:
"Highlights include:
- Fix a couple of mount regressions due to the recent cleanups.
- Fix an Oops in the open recovery code
- Fix an rpc_pipefs upcall hang that results from some of the net
namespace work from 3.4.x (stable kernel candidate).
- Fix a couple of write and o_direct regressions that were found at
last weeks Bakeathon testing event in Ann Arbor."
* tag 'nfs-for-3.5-2' of git://git.linux-nfs.org/projects/trondmy/linux-nfs:
NFS: add an endian notation for sparse
NFSv4.1: integer overflow in decode_cb_sequence_args()
rpc_pipefs: allow rpc_purge_list to take a NULL waitq pointer
NFSv4 do not send an empty SETATTR compound
NFSv2: EOF incorrectly set on short read
NFS: Use the NFS_DEFAULT_VERSION for v2 and v3 mounts
NFS: fix directio refcount bug on commit
NFSv4: Fix unnecessary delegation returns in nfs4_do_open
NFSv4.1: Convert another trivial printk into a dprintk
NFS4: Fix open bug when pnfs module blacklisted
NFS: Remove incorrect BUG_ON in nfs_found_client
NFS: Map minor mismatch error to protocol not support error.
NFS: Fix a commit bug
NFS4: Set parsed mount data version to 4
NFSv4.1: Ensure we clear session state flags after a session creation
NFSv4.1: Convert a trivial printk into a dprintk
NFSv4: Fix up decode_attr_mdsthreshold
NFSv4: Fix an Oops in the open recovery code
NFSv4.1: Fix a request leak on the back channel
Pull the rest of the nfsd commits from Bruce Fields:
"... and then I cherry-picked the remainder of the patches from the
head of my previous branch"
This is the rest of the original nfsd branch, rebased without the
delegation stuff that I thought really needed to be redone.
I don't like rebasing things like this in general, but in this situation
this was the lesser of two evils.
* 'for-3.5' of git://linux-nfs.org/~bfields/linux: (50 commits)
nfsd4: fix, consolidate client_has_state
nfsd4: don't remove rebooted client record until confirmation
nfsd4: remove some dprintk's and a comment
nfsd4: return "real" sequence id in confirmed case
nfsd4: fix exchange_id to return confirm flag
nfsd4: clarify that renewing expired client is a bug
nfsd4: simpler ordering of setclientid_confirm checks
nfsd4: setclientid: remove pointless assignment
nfsd4: fix error return in non-matching-creds case
nfsd4: fix setclientid_confirm same_cred check
nfsd4: merge 3 setclientid cases to 2
nfsd4: pull out common code from setclientid cases
nfsd4: merge last two setclientid cases
nfsd4: setclientid/confirm comment cleanup
nfsd4: setclientid remove unnecessary terms from a logical expression
nfsd4: move rq_flavor into svc_cred
nfsd4: stricter cred comparison for setclientid/exchange_id
nfsd4: move principal name into svc_cred
nfsd4: allow removing clients not holding state
nfsd4: rearrange exchange_id logic to simplify
...
The idea is to separate service destruction and per-net operations,
because these are two different things and the mix looks ugly.
Notes:
1) For NFS server this patch looks ugly (sorry for that). But these
place will be rewritten soon during NFSd containerization.
2) LockD per-net counter increase int lockd_up() was moved prior to
make_socks() to make lockd_down_net() call safe in case of error.
Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
This new routine is responsible for service registration in a specified
network context.
The idea is to separate service creation from per-net operations.
Note also: since registering service with svc_bind() can fail, the
service will be destroyed and during destruction it will try to
unregister itself from rpcbind. In this case unregistration has to be
skipped.
Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
If the call to svc_process_common() fails, then the request
needs to be freed before we can exit bc_svc_process.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Cc: stable@vger.kernel.org
Standardize the net core ratelimited logging functions.
Coalesce formats, align arguments.
Change a printk then vprintk sequence to use printf extension %pV.
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch introduces per-net Lockd initialization and destruction routines.
The logic is the same as in global Lockd up and down routines. Probably the
solution is not the best one. But at least it looks clear.
So per-net "up" routine are called only in case of lockd is running already. If
per-net resources are not allocated yet, then service is being registered with
local portmapper and lockd sockets created.
Per-net "down" routine is called on every lockd_down() call in case of global
users counter is not zero.
Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
This function is enough for releasing resources, allocated for network
namespace context, in case of sharing service between them.
IOW, each service "user" (LockD, NFSd, etc), which wants to share service
between network namespaces, have to release related resources by the function,
introduced in this patch, instead of performing service shutdown (of course in
case the service is shared already to the moment of release).
Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
v2: Added comment to BUG_ON's in svc_destroy() to make code looks clearer.
This patch introduces network namespace filter for service destruction
function.
Nothing special here - just do exactly the same operations, but only for
tranports in passed networks namespace context.
BTW, BUG_ON() checks for empty service transports lists were returned into
svc_destroy() function. This is because of swithing generic svc_close_all() to
networks namespace dependable svc_close_net().
Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
On service shutdown we can be sure, that no more users of it left except
current. Thus it looks like using current network namespace context is safe in
this case.
Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Service, using rpcbind (Lockd, NFSd) are starting from userspace call and thus
we can use current network namespace.
There could be a problem with NFSd service, because it's creation can be called
through NFSd fs from different network namespace. But this is a part of "NFSd
per net ns" task and will be fixed in future.
Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Lockd and NFSd services will handle requests from and to many network
nsamespaces. And thus have to be registered and unregistered per network
namespace.
Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
These client are per network namespace and thus can be created for different
network namespaces.
Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Registering rpcbind program requires rpcbind clients, which are per network
namespace context.
Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
* 'for-3.3' of git://linux-nfs.org/~bfields/linux: (31 commits)
nfsd4: nfsd4_create_clid_dir return value is unused
NFSD: Change name of extended attribute containing junction
svcrpc: don't revert to SVC_POOL_DEFAULT on nfsd shutdown
svcrpc: fix double-free on shutdown of nfsd after changing pool mode
nfsd4: be forgiving in the absence of the recovery directory
nfsd4: fix spurious 4.1 post-reboot failures
NFSD: forget_delegations should use list_for_each_entry_safe
NFSD: Only reinitilize the recall_lru list under the recall lock
nfsd4: initialize special stateid's at compile time
NFSd: use network-namespace-aware cache registering routines
SUNRPC: create svc_xprt in proper network namespace
svcrpc: update outdated BKL comment
nfsd41: allow non-reclaim open-by-fh's in 4.1
svcrpc: avoid memory-corruption on pool shutdown
svcrpc: destroy server sockets all at once
svcrpc: make svc_delete_xprt static
nfsd: Fix oops when parsing a 0 length export
nfsd4: Use kmemdup rather than duplicating its implementation
nfsd4: add a separate (lockowner, inode) lookup
nfsd4: fix CONFIG_NFSD_FAULT_INJECTION compile error
...
This was unexpected behavior (at least for me)--why would you want
configuration settings automatically lost on nfsd restart?
In practice this won't affect distributions, which likely set everything
on every startup. But I'd expect the behavior to be less confusing to
someone manually restarting nfsd for testing.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
The pool_to and to_pool fields of the global svc_pool_map are freed on
shutdown, but are initialized in nfsd startup only in the
SVC_POOL_PERCPU and SVC_POOL_PERNODE cases.
They *are* initialized to zero on kernel startup. So as long as you use
only SVC_POOL_GLOBAL (the default), this will never be a problem.
You're also OK if you only ever use SVC_POOL_PERCPU or SVC_POOL_PERNODE.
However, the following sequence events leads to a double-free:
1. set SVC_POOL_PERCPU or SVC_POOL_PERNODE
2. start nfsd: both fields are initialized.
3. shutdown nfsd: both fields are freed.
4. set SVC_POOL_GLOBAL
5. start nfsd: the fields are left untouched.
6. shutdown nfsd: now we try to free them again.
Step 4 is actually unnecessary, since (for some bizarre reason), nfsd
automatically resets the pool mode to SVC_POOL_GLOBAL on shutdown.
Cc: stable@kernel.org
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Instead of testing defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Socket callbacks use svc_xprt_enqueue() to add an xprt to a
pool->sp_sockets list. In normal operation a server thread will later
come along and take the xprt off that list. On shutdown, after all the
threads have exited, we instead manually walk the sv_tempsocks and
sv_permsocks lists to find all the xprt's and delete them.
So the sp_sockets lists don't really matter any more. As a result,
we've mostly just ignored them and hoped they would go away.
Which has gotten us into trouble; witness for example ebc63e531c
"svcrpc: fix list-corrupting race on nfsd shutdown", the result of Ben
Greear noticing that a still-running svc_xprt_enqueue() could re-add an
xprt to an sp_sockets list just before it was deleted. The fix was to
remove it from the list at the end of svc_delete_xprt(). But that only
made corruption less likely--I can see nothing that prevents a
svc_xprt_enqueue() from adding another xprt to the list at the same
moment that we're removing this xprt from the list. In fact, despite
the earlier xpo_detach(), I don't even see what guarantees that
svc_xprt_enqueue() couldn't still be running on this xprt.
So, instead, note that svc_xprt_enqueue() essentially does:
lock sp_lock
if XPT_BUSY unset
add to sp_sockets
unlock sp_lock
So, if we do:
set XPT_BUSY on every xprt.
Empty every sp_sockets list, under the sp_socks locks.
Then we're left knowing that the sp_sockets lists are all empty and will
stay that way, since any svc_xprt_enqueue() will check XPT_BUSY under
the sp_lock and see it set.
And *then* we can continue deleting the xprt's.
(Thanks to Jeff Layton for being correctly suspicious of this code....)
Cc: Ben Greear <greearb@candelatech.com>
Cc: Jeff Layton <jlayton@redhat.com>
Cc: stable@kernel.org
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
There's no reason I can see that we need to call sv_shutdown between
closing the two lists of sockets.
Cc: stable@kernel.org
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
We have to call svc_rpcb_cleanup() explicitly from nfsd_last_thread() since
this function is registered as service shutdown callback and thus nobody else
will done it for us.
Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
