We are now keeping the MTU information synced between asoc, transport
and dst, which makes the check at sctp_packet_config() not needed
anymore. As it was the sole caller to this function, lets remove it.
Signed-off-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Which makes sure that the MTU respects the minimum value of
SCTP_DEFAULT_MINSEGMENT and that it is correctly aligned.
Signed-off-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
and avoid the open-coded versions of it.
Now sctp_datamsg_from_user can just re-use asoc->frag_point as it will
always be updated.
Signed-off-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
When given a MTU, this function calculates how much payload we can carry
on it. Without a MTU, it calculates the amount of header overhead we
have.
So that when we have extra overhead, like the one added for IP options
on SELinux patches, it is easier to handle it.
Signed-off-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
All changes to asoc PMTU should now go through this wrapper, making it
easier to track them and to do other actions upon it.
Signed-off-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
As noticed by Xin Long, the if() here is always true as PMTU can never
be 0.
Reported-by: Xin Long <lucien.xin@gmail.com>
Signed-off-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
There was only one case that sctp_assoc_add_peer couldn't handle, which
is when SPP_PMTUD_DISABLE is set and pathmtu not initialized.
So add this situation to sctp_transport_route and reuse what was
already in there.
Signed-off-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
In tcp_select_initial_window(), we only set rcv_wnd to
tcp_default_init_rwnd() if current mss > (1 << wscale). Otherwise,
rcv_wnd is kept at the full receive space of the socket which is a
value way larger than tcp_default_init_rwnd().
With larger initial rcv_wnd value, receive buffer autotuning logic
takes longer to kick in and increase the receive buffer.
In a TCP throughput test where receiver has rmem[2] set to 125MB
(wscale is 11), we see the connection gets recvbuf limited at the
beginning of the connection and gets less throughput overall.
Signed-off-by: Wei Wang <weiwan@google.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Acked-by: Soheil Hassas Yeganeh <soheil@google.com>
Acked-by: Yuchung Cheng <ycheng@google.com>
Acked-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
If sockopt TCP_DEFER_ACCEPT is set, the accept is delayed till
data is available.
Signed-off-by: Ursula Braun <ubraun@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Setting sockopt TCP_NODELAY or resetting sockopt TCP_CORK
triggers data transfer.
For a corked SMC socket RDMA writes are deferred, if there is
still sufficient send buffer space available.
Signed-off-by: Ursula Braun <ubraun@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Several TCP sockopts do not work for SMC. One example are the
TCP_FASTOPEN sockopts, since SMC-connection setup is based on the TCP
three-way-handshake.
If the SMC socket is still in state SMC_INIT, such sockopts trigger
fallback to TCP. Otherwise an error is returned.
Signed-off-by: Ursula Braun <ubraun@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The struct smc_cdc_msg must be defined as packed so the
size is 44 bytes.
And change the structure size check so sizeof is checked.
Signed-off-by: Karsten Graul <kgraul@linux.ibm.com>
Signed-off-by: Ursula Braun <ubraun@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
kbuild test robot says:
>coccinelle warnings: (new ones prefixed by >>)
>>> net/core/dev.c:1588:2-3: Unneeded semicolon
So, let's remove it.
Reported-by: kbuild test robot <lkp@intel.com>
Signed-off-by: Kirill Tkhai <ktkhai@virtuozzo.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Use hlist_entry_safe() instead of open-coding it.
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Reviewed-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Reviewed-by: Stephen Hemminger <stephen@networkplumber.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Implement the same type of ethtool diversion that we have for
ETH_SS_STATS and make it work with ETH_SS_PHY_STATS. This allows
providing PHY level statistics for CPU ports that are directly
connecting to a PHY device.
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
In preparation for having more call sites attempting to obtain a
reference against a PHY device corresponding to a particular port,
introduce a helper function for that purpose.
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Up until now we largely assumed that we were interested in ETH_SS_STATS
type of strings for all ethtool operations, this is about to change with
the introduction of additional string sets, e.g: ETH_SS_PHY_STATS.
Update all functions to take an appropriate stringset argument and act
on it when it is different than ETH_SS_STATS for now.
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This is completely redundant with what netdev_set_default_ethtool_ops()
does, we are always guaranteed to have a valid dev->ethtool_ops pointer,
however, within that structure, not all function calls may be populated,
so we still have to check them individually.
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add a new callback: get_ethtool_phy_stats() which allows network device
drivers not making use of the PHY library to return PHY statistics.
Update ethtool_get_phy_stats(), __ethtool_get_sset_count() and
__ethtool_get_strings() accordingly to interogate the network device
about ETH_SS_PHY_STATS.
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
In order to make it possible for network device drivers that do not
necessarily have a phy_device attached, but still report PHY statistics,
have a preliminary refactoring consisting in creating helper functions
that encapsulate the PHY device driver knowledge within PHYLIB.
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The 'pppol2tp' procfs and 'l2tp/tunnels' debugfs files handle reference
counting of sessions differently than for tunnels.
For consistency, use the same mechanism for handling both sessions and
tunnels. That is, drop the reference on the previous session just
before looking up the next one (rather than in .show()). If necessary
(if dump stops before *_next_session() returns NULL), drop the last
reference in .stop().
Signed-off-by: Guillaume Nault <g.nault@alphalink.fr>
Signed-off-by: David S. Miller <davem@davemloft.net>
After the introduction of a 128-bit node identity it may be difficult
for a user to correlate between this identity and the generated node
hash address.
We now try to make this easier by introducing a new ioctl() call for
fetching a node identity by using the hash value as key. This will
be particularly useful when we extend some of the commands in the
'tipc' tool, but we also expect regular user applications to need
this feature.
Acked-by: Ying Xue <ying.xue@windriver.com>
Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Daniel Borkmann says:
====================
pull-request: bpf-next 2018-04-27
The following pull-request contains BPF updates for your *net-next* tree.
The main changes are:
1) Add extensive BPF helper description into include/uapi/linux/bpf.h
and a new script bpf_helpers_doc.py which allows for generating a
man page out of it. Thus, every helper in BPF now comes with proper
function signature, detailed description and return code explanation,
from Quentin.
2) Migrate the BPF collect metadata tunnel tests from BPF samples over
to the BPF selftests and further extend them with v6 vxlan, geneve
and ipip tests, simplify the ipip tests, improve documentation and
convert to bpf_ntoh*() / bpf_hton*() api, from William.
3) Currently, helpers that expect ARG_PTR_TO_MAP_{KEY,VALUE} can only
access stack and packet memory. Extend this to allow such helpers
to also use map values, which enabled use cases where value from
a first lookup can be directly used as a key for a second lookup,
from Paul.
4) Add a new helper bpf_skb_get_xfrm_state() for tc BPF programs in
order to retrieve XFRM state information containing SPI, peer
address and reqid values, from Eyal.
5) Various optimizations in nfp driver's BPF JIT in order to turn ADD
and SUB instructions with negative immediate into the opposite
operation with a positive immediate such that nfp can better fit
small immediates into instructions. Savings in instruction count
up to 4% have been observed, from Jakub.
6) Add the BPF prog's gpl_compatible flag to struct bpf_prog_info
and add support for dumping this through bpftool, from Jiri.
7) Move the BPF sockmap samples over into BPF selftests instead since
sockmap was rather a series of tests than sample anyway and this way
this can be run from automated bots, from John.
8) Follow-up fix for bpf_adjust_tail() helper in order to make it work
with generic XDP, from Nikita.
9) Some follow-up cleanups to BTF, namely, removing unused defines from
BTF uapi header and renaming 'name' struct btf_* members into name_off
to make it more clear they are offsets into string section, from Martin.
10) Remove test_sock_addr from TEST_GEN_PROGS in BPF selftests since
not run directly but invoked from test_sock_addr.sh, from Yonghong.
11) Remove redundant ret assignment in sample BPF loader, from Wang.
12) Add couple of missing files to BPF selftest's gitignore, from Anders.
There are two trivial merge conflicts while pulling:
1) Remove samples/sockmap/Makefile since all sockmap tests have been
moved to selftests.
2) Add both hunks from tools/testing/selftests/bpf/.gitignore to the
file since git should ignore all of them.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
When bpf_adjust_tail was introduced for generic xdp, it changed skb's tail
pointer, so it was pointing to the new "end of the packet". However skb's
len field wasn't properly modified, so on the wire ethernet frame had
original (or even bigger, if adjust_head was used) size. This diff is
fixing this.
Fixes: 198d83bb3 (" bpf: make generic xdp compatible w/ bpf_xdp_adjust_tail")
Signed-off-by: Nikita V. Shirokov <tehnerd@tehnerd.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Virtual devices such as tunnels and bonding can handle large packets.
Only segment packets when reaching a physical or loopback device.
Signed-off-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Allow specifying segment size in the send call.
The new control message performs the same function as socket option
UDP_SEGMENT while avoiding the extra system call.
[ Export udp_cmsg_send for ipv6. -DaveM ]
Signed-off-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
When sending large datagrams that are later segmented, store data in
page frags to avoid copying from linear in skb_segment.
Signed-off-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
skb_segment by default transfers allocated wmem from the gso skb
to the tail of the segment list. This underreports real truesize
of the list, especially if the tail might be dropped.
Similar to tcp_gso_segment, update wmem_alloc with the aggregate
list truesize and make each segment responsible for its own
share by setting skb->destructor.
Clear gso_skb->destructor prior to calling skb_segment to skip
the default assignment to tail.
Signed-off-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Support generic segmentation offload for udp datagrams. Callers can
concatenate and send at once the payload of multiple datagrams with
the same destination.
To set segment size, the caller sets socket option UDP_SEGMENT to the
length of each discrete payload. This value must be smaller than or
equal to the relevant MTU.
A follow-up patch adds cmsg UDP_SEGMENT to specify segment size on a
per send call basis.
Total byte length may then exceed MTU. If not an exact multiple of
segment size, the last segment will be shorter.
The implementation adds a gso_size field to the udp socket, ip(v6)
cmsg cookie and inet_cork structure to be able to set the value at
setsockopt or cmsg time and to work with both lockless and corked
paths.
Initial benchmark numbers show UDP GSO about as expensive as TCP GSO.
tcp tso
3197 MB/s 54232 msg/s 54232 calls/s
6,457,754,262 cycles
tcp gso
1765 MB/s 29939 msg/s 29939 calls/s
11,203,021,806 cycles
tcp without tso/gso *
739 MB/s 12548 msg/s 12548 calls/s
11,205,483,630 cycles
udp
876 MB/s 14873 msg/s 624666 calls/s
11,205,777,429 cycles
udp gso
2139 MB/s 36282 msg/s 36282 calls/s
11,204,374,561 cycles
[*] after reverting commit 0a6b2a1dc2
("tcp: switch to GSO being always on")
Measured total system cycles ('-a') for one core while pinning both
the network receive path and benchmark process to that core:
perf stat -a -C 12 -e cycles \
./udpgso_bench_tx -C 12 -4 -D "$DST" -l 4
Note the reduction in calls/s with GSO. Bytes per syscall drops
increases from 1470 to 61818.
Signed-off-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Implement generic segmentation offload support for udp datagrams. A
follow-up patch adds support to the protocol stack to generate such
packets.
UDP GSO is not UFO. UFO fragments a single large datagram. GSO splits
a large payload into a number of discrete UDP datagrams.
The implementation adds a GSO type SKB_UDP_GSO_L4 to differentiate it
from UFO (SKB_UDP_GSO).
IPPROTO_UDPLITE is excluded, as that protocol has no gso handler
registered.
[ Export __udp_gso_segment for ipv6. -DaveM ]
Signed-off-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
UDP segmentation offload needs access to inet_cork in the udp layer.
Pass the struct to ip(6)_make_skb instead of allocating it on the
stack in that function itself.
This patch is a noop otherwise.
Signed-off-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Daniel Borkmann says:
====================
pull-request: bpf 2018-04-25
The following pull-request contains BPF updates for your *net* tree.
The main changes are:
1) Fix to clear the percpu metadata_dst that could otherwise carry
stale ip_tunnel_info, from William.
2) Fix that reduces the number of passes in x64 JIT with regards to
dead code sanitation to avoid risk of prog rejection, from Gianluca.
3) Several fixes of sockmap programs, besides others, fixing a double
page_put() in error path, missing refcount hold for pinned sockmap,
adding required -target bpf for clang in sample Makefile, from John.
4) Fix to disable preemption in __BPF_PROG_RUN_ARRAY() paths, from Roman.
5) Fix tools/bpf/ Makefile with regards to a lex/yacc build error
seen on older gcc-5, from John.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
The function rds_ib_setup_qp is calling rds_ib_get_client_data and
should correspondingly call rds_ib_dev_put. This call was lost in
the non-error path with the introduction of error handling done in
commit 3b12f73a5c ("rds: ib: add error handle")
Signed-off-by: Dag Moxnes <dag.moxnes@oracle.com>
Reviewed-by: Håkon Bugge <haakon.bugge@oracle.com>
Acked-by: Santosh Shilimkar <santosh.shilimkar@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The internal CLC socket should exist till the SMC-socket is released.
Function tcp_listen_worker() releases the internal CLC socket of a
listen socket, if an smc_close_active() is called. This function
is called for the final release(), but it is called for shutdown
SHUT_RDWR as well. This opens a door for protection faults, if
socket calls using the internal CLC socket are called for a
shutdown listen socket.
With the changes of
commit 3d50206759 ("net/smc: simplify wait when closing listen socket")
there is no need anymore to release the internal CLC socket in
function tcp_listen_worker((). It is sufficient to release it in
smc_release().
Fixes: 127f497058 ("net/smc: release clcsock from tcp_listen_worker")
Signed-off-by: Ursula Braun <ubraun@linux.ibm.com>
Reported-by: syzbot+9045fc589fcd196ef522@syzkaller.appspotmail.com
Reported-by: syzbot+28a2c86cf19c81d871fa@syzkaller.appspotmail.com
Reported-by: syzbot+9605e6cace1b5efd4a0a@syzkaller.appspotmail.com
Reported-by: syzbot+cf9012c597c8379d535c@syzkaller.appspotmail.com
Signed-off-by: David S. Miller <davem@davemloft.net>
After Commit 4f00878126 ("sctp: apply rhashtable api to send/recv
path"), there's no place using sctp_assoc_is_match, so remove it.
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Move the check on FRA_L3MDEV attribute to helper to improve the
readability of fib_nl2rule. Update the extack messages to be
clear when the configuration option is disabled versus an invalid
value has been passed.
Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
It's currently written as:
if (!tchunk->tsn_gap_acked) { [1]
tchunk->tsn_gap_acked = 1;
...
}
if (TSN_lte(tsn, sack_ctsn)) {
if (!tchunk->tsn_gap_acked) {
/* SFR-CACC processing */
...
}
}
Which causes the SFR-CACC processing on ack reception to never process,
as tchunk->tsn_gap_acked is always true by then. Block [1] was
moved to that position by the commit marked below.
This patch fixes it by doing SFR-CACC processing earlier, before
tsn_gap_acked is set to true.
Fixes: 31b02e1549 ("sctp: Failover transmitted list on transport delete")
Signed-off-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Reviewed-by: Xin Long <lucien.xin@gmail.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
sctp_make_sack() make changes to the asoc and this cast is just
bypassing the const attribute. As there is no need to have the const
there, just remove it and fix the violation.
Signed-off-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Reviewed-by: Xin Long <lucien.xin@gmail.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch extends NTF_EXT_LEARNED support to the neighbour system.
Example use-case: An Ethernet VPN implementation (eg in FRR routing suite)
can use this flag to add dynamic reachable external neigh entires
learned via control plane. The use of neigh NTF_EXT_LEARNED in this
patch is consistent with its use with bridge and vxlan fdb entries.
Signed-off-by: Roopa Prabhu <roopa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The addrconf_ifdown() evaluates keep_addr_on_down state twice. There
is no need to do it.
Cc: David Ahern <dsahern@gmail.com>
Signed-off-by: Ivan Vecera <cera@cera.cz>
Signed-off-by: David S. Miller <davem@davemloft.net>
ECMP (equal-cost multipath) hashes are typically computed on the packets'
5-tuple(src IP, dst IP, src port, dst port, L4 proto).
For encapsulated packets, the L4 data is not readily available and ECMP
hashing will often revert to (src IP, dst IP). This will lead to traffic
polarization on a single ECMP path, causing congestion and waste of network
capacity.
In IPv6, the 20-bit flow label field is also used as part of the ECMP hash.
In the lack of L4 data, the hashing will be on (src IP, dst IP, flow
label). Having a non-zero flow label is thus important for proper traffic
load balancing when L4 data is unavailable (i.e., when packets are
encapsulated).
Currently, the seg6_do_srh_encap() function extracts the original packet's
flow label and set it as the outer IPv6 flow label. There are two issues
with this behaviour:
a) There is no guarantee that the inner flow label is set by the source.
b) If the original packet is not IPv6, the flow label will be set to
zero (e.g., IPv4 or L2 encap).
This patch adds a function, named seg6_make_flowlabel(), that computes a
flow label from a given skb. It supports IPv6, IPv4 and L2 payloads, and
leverages the per namespace 'seg6_flowlabel" sysctl value.
The currently support behaviours are as follows:
-1 set flowlabel to zero.
0 copy flowlabel from Inner paceket in case of Inner IPv6
(Set flowlabel to 0 in case IPv4/L2)
1 Compute the flowlabel using seg6_make_flowlabel()
This patch has been tested for IPv6, IPv4, and L2 traffic.
Signed-off-by: Ahmed Abdelsalam <amsalam20@gmail.com>
Acked-by: David Lebrun <dlebrun@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The percpu metadata_dst might carry the stale ip_tunnel_info
and cause incorrect behavior. When mixing tests using ipv4/ipv6
bpf vxlan and geneve tunnel, the ipv6 tunnel info incorrectly uses
ipv4's src ip addr as its ipv6 src address, because the previous
tunnel info does not clean up. The patch zeros the fields in
ip_tunnel_info.
Signed-off-by: William Tu <u9012063@gmail.com>
Reported-by: Yifeng Sun <pkusunyifeng@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
This commit introduces a helper which allows fetching xfrm state
parameters by eBPF programs attached to TC.
Prototype:
bpf_skb_get_xfrm_state(skb, index, xfrm_state, size, flags)
skb: pointer to skb
index: the index in the skb xfrm_state secpath array
xfrm_state: pointer to 'struct bpf_xfrm_state'
size: size of 'struct bpf_xfrm_state'
flags: reserved for future extensions
The helper returns 0 on success. Non zero if no xfrm state at the index
is found - or non exists at all.
struct bpf_xfrm_state currently includes the SPI, peer IPv4/IPv6
address and the reqid; it can be further extended by adding elements to
its end - indicating the populated fields by the 'size' argument -
keeping backwards compatibility.
Typical usage:
struct bpf_xfrm_state x = {};
bpf_skb_get_xfrm_state(skb, 0, &x, sizeof(x), 0);
...
Signed-off-by: Eyal Birger <eyal.birger@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
rt6_remove_exception_rt() is called under rcu_read_lock() only.
We lock rt6_exception_lock a bit later, so we do not hold
rt6_exception_lock yet.
Fixes: 8a14e46f14 ("net/ipv6: Fix missing rcu dereferences on from")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Cc: David Ahern <dsahern@gmail.com>
Acked-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
A duplicated null check on sgout is redundant as it is known to be
already true because of the identical earlier check. Remove it.
Detected by cppcheck:
net/tls/tls_sw.c:696: (warning) Identical inner 'if' condition is always
true.
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Distributed filesystems are most effective when the server and client
clocks are synchronised. Embedded devices often use NFS for their
root filesystem but typically do not contain an RTC, so the clocks of
the NFS server and the embedded device will be out-of-sync when the root
filesystem is mounted (and may not be synchronised until late in the
boot process).
Extend ipconfig with the ability to export IP addresses of NTP servers
it discovers to /proc/net/ipconfig/ntp_servers. They can be supplied as
follows:
- If ipconfig is configured manually via the "ip=" or "nfsaddrs="
kernel command line parameters, one NTP server can be specified in
the new "<ntp0-ip>" parameter.
- If ipconfig is autoconfigured via DHCP, request DHCP option 42 in
the DHCPDISCOVER message, and record the IP addresses of up to three
NTP servers sent by the responding DHCP server in the subsequent
DHCPOFFER message.
ipconfig will only write the NTP server IP addresses it discovers to
/proc/net/ipconfig/ntp_servers, one per line (in the order received from
the DHCP server, if DHCP autoconfiguration is used); making use of these
NTP servers is the responsibility of a user space process (e.g. an
initrd/initram script that invokes an NTP client before mounting an NFS
root filesystem).
Signed-off-by: Chris Novakovic <chris@chrisn.me.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
To allow ipconfig to report IP configuration details to user space
processes without cluttering /proc/net, create a new subdirectory
/proc/net/ipconfig. All files containing IP configuration details should
be written to this directory.
Signed-off-by: Chris Novakovic <chris@chrisn.me.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
