Commit Graph

345 Commits

Author SHA1 Message Date
Trond Myklebust
ac3c860c75 NFS: NFSoRDMA Client Side Changes
In addition to a variety of bugfixes, these patches are mostly geared at
 enabling both swap and backchannel support to the NFS over RDMA client.
 
 Signed-off-by: Anna Schumake <Anna.Schumaker@Netapp.com>
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Merge tag 'nfs-rdma-4.4-2' of git://git.linux-nfs.org/projects/anna/nfs-rdma

NFS: NFSoRDMA Client Side Changes

In addition to a variety of bugfixes, these patches are mostly geared at
enabling both swap and backchannel support to the NFS over RDMA client.

Signed-off-by: Anna Schumake <Anna.Schumaker@Netapp.com>
2015-11-02 17:09:24 -05:00
Chuck Lever
76566773a1 NFS: Enable client side NFSv4.1 backchannel to use other transports
Forechannel transports get their own "bc_up" method to create an
endpoint for the backchannel service.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
[Anna Schumaker: Add forward declaration of struct net to xprt.h]
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2015-11-02 16:29:13 -05:00
Chuck Lever
42e5c3e272 SUNRPC: Abstract backchannel operations
xprt_{setup,destroy}_backchannel() won't be adequate for RPC/RMDA
bi-direction. In particular, receive buffers have to be pre-
registered and posted in order to receive incoming backchannel
requests.

Add a virtual function call to allow the insertion of appropriate
backchannel setup and destruction methods for each transport.

In addition, freeing a backchannel request is a little different
for RPC/RDMA. Introduce an rpc_xprt_op to handle the difference.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-by: Sagi Grimberg <sagig@mellanox.com>
Tested-By: Devesh Sharma <devesh.sharma@avagotech.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2015-11-02 13:45:15 -05:00
Trond Myklebust
31303d6cbb SUNRPC: Use MSG_SENDPAGE_NOTLAST in xs_send_pagedata()
If we're sending more than one page via kernel_sendpage(), then set
MSG_SENDPAGE_NOTLAST between the pages so that we don't send suboptimal
frames (see commit 2f53384424 and commit 35f9c09fe9).

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-10-08 09:12:35 -04:00
Trond Myklebust
a26480942c SUNRPC: Move AF_LOCAL receive data path into a workqueue context
Now that we've done it for TCP and UDP, let's convert AF_LOCAL as well.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-10-08 08:27:05 -04:00
Trond Myklebust
f9b2ee714c SUNRPC: Move UDP receive data path into a workqueue context
Now that we've done it for TCP, let's convert UDP as well.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-10-08 08:27:04 -04:00
Trond Myklebust
edc1b01cd3 SUNRPC: Move TCP receive data path into a workqueue context
Stream protocols such as TCP can often build up a backlog of data to be
read due to ordering. Combine this with the fact that some workloads such
as NFS read()-intensive workloads need to receive a lot of data per RPC
call, and it turns out that receiving the data from inside a softirq
context can cause starvation.

The following patch moves the TCP data receive into a workqueue context.
We still end up calling tcp_read_sock(), but we do so from a process
context, meaning that softirqs are enabled for most of the time.

With this patch, I see a doubling of read bandwidth when running a
multi-threaded iozone workload between a virtual client and server setup.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-10-08 08:27:04 -04:00
Trond Myklebust
66d7a56a62 SUNRPC: Refactor TCP receive
Move the TCP data receive loop out of xs_tcp_data_ready(). Doing so
will allow us to move the data receive out of the softirq context in
a set of followup patches.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-10-08 08:27:04 -04:00
Trond Myklebust
4b0ab51db3 SUNRPC: xs_sock_mark_closed() does not need to trigger socket autoclose
Under all conditions, it should be quite sufficient just to mark
the socket as disconnected. It will then be closed by the
transport shutdown or reconnect code.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-09-19 16:38:35 -04:00
Trond Myklebust
0fdea1e8a2 SUNRPC: Ensure that we wait for connections to complete before retrying
Commit 718ba5b873, moved the responsibility for unlocking the socket to
xs_tcp_setup_socket, meaning that the socket will be unlocked before we
know that it has finished trying to connect. The following patch is based on
an initial patch by Russell King to ensure that we delay clearing the
XPRT_CONNECTING flag until we either know that we failed to initiate
a connection attempt, or the connection attempt itself failed.

Fixes: 718ba5b873 ("SUNRPC: Add helpers to prevent socket create from racing")
Reported-by: Russell King <linux@arm.linux.org.uk>
Reported-by: Russell King <rmk+kernel@arm.linux.org.uk>
Tested-by: Russell King <rmk+kernel@arm.linux.org.uk>
Tested-by: Benjamin Coddington <bcodding@redhat.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-09-17 18:01:28 -04:00
Trond Myklebust
03c78827db SUNRPC: Fix races between socket connection and destroy code
When we're destroying the socket transport, we need to ensure that
we cancel any existing delayed connection attempts, and order them
w.r.t. the call to xs_close().

Reported-by:"Suzuki K. Poulose" <suzuki.poulose@arm.com>
Acked-by: Jeff Layton <jlayton@poochiereds.net>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-09-17 15:48:23 -04:00
Trond Myklebust
099392048c SUNRPC: Prevent SYN+SYNACK+RST storms
Add a shutdown() call before we release the socket in order to ensure the
reset is sent before we try to reconnect.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-08-29 19:11:21 -07:00
Trond Myklebust
0c78789e3a SUNRPC: xs_reset_transport must mark the connection as disconnected
In case the reconnection attempt fails.

Cc: stable@vger.kernel.org
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-08-29 13:40:32 -07:00
Trond Myklebust
c2126157ea SUNRPC: Allow sockets to do GFP_NOIO allocations
Follow up to commit c4a7ca7749 ("SUNRPC: Allow waiting on memory
allocation"). Allows the RPC socket code to do non-IO blocking.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-08-19 21:46:15 -05:00
Trond Myklebust
99b1a4c32a SUNRPC: Fix a thinko in xs_connect()
It is rather pointless to test the value of transport->inet after
calling xs_reset_transport(), since it will always be zero, and
so we will never see any exponential back off behaviour.
Also don't force early connections for SOFTCONN tasks. If the server
disconnects us, we should respect the exponential backoff.

Cc: stable@vger.kernel.org # 4.0+
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-08-17 13:05:49 -05:00
Linus Torvalds
d8132e08d2 NFS client bugfixes for Linux 4.2
Highlights include:
 
 Stable patches:
 - Fix a situation where the client uses the wrong (zero) stateid.
 - Fix a memory leak in nfs_do_recoalesce
 
 Bugfixes:
 - Plug a memory leak when ->prepare_layoutcommit fails
 - Fix an Oops in the NFSv4 open code
 - Fix a backchannel deadlock
 - Fix a livelock in sunrpc when sendmsg fails due to low memory availability
 - Don't revalidate the mapping if both size and change attr are up to date
 - Ensure we don't miss a file extension when doing pNFS
 - Several fixes to handle NFSv4.1 sequence operation status bits correctly
 - Several pNFS layout return bugfixes
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Merge tag 'nfs-for-4.2-2' of git://git.linux-nfs.org/projects/trondmy/linux-nfs

Pull NFS client bugfixes from Trond Myklebust:
 "Highlights include:

  Stable patches:
   - Fix a situation where the client uses the wrong (zero) stateid.
   - Fix a memory leak in nfs_do_recoalesce

  Bugfixes:
   - Plug a memory leak when ->prepare_layoutcommit fails
   - Fix an Oops in the NFSv4 open code
   - Fix a backchannel deadlock
   - Fix a livelock in sunrpc when sendmsg fails due to low memory
     availability
   - Don't revalidate the mapping if both size and change attr are up to
     date
   - Ensure we don't miss a file extension when doing pNFS
   - Several fixes to handle NFSv4.1 sequence operation status bits
     correctly
   - Several pNFS layout return bugfixes"

* tag 'nfs-for-4.2-2' of git://git.linux-nfs.org/projects/trondmy/linux-nfs: (28 commits)
  nfs: Fix an oops caused by using other thread's stack space in ASYNC mode
  nfs: plug memory leak when ->prepare_layoutcommit fails
  SUNRPC: Report TCP errors to the caller
  sunrpc: translate -EAGAIN to -ENOBUFS when socket is writable.
  NFSv4.2: handle NFS-specific llseek errors
  NFS: Don't clear desc->pg_moreio in nfs_do_recoalesce()
  NFS: Fix a memory leak in nfs_do_recoalesce
  NFS: nfs_mark_for_revalidate should always set NFS_INO_REVAL_PAGECACHE
  NFS: Remove the "NFS_CAP_CHANGE_ATTR" capability
  NFS: Set NFS_INO_REVAL_PAGECACHE if the change attribute is uninitialised
  NFS: Don't revalidate the mapping if both size and change attr are up to date
  NFSv4/pnfs: Ensure we don't miss a file extension
  NFSv4: We must set NFS_OPEN_STATE flag in nfs_resync_open_stateid_locked
  SUNRPC: xprt_complete_bc_request must also decrement the free slot count
  SUNRPC: Fix a backchannel deadlock
  pNFS: Don't throw out valid layout segments
  pNFS: pnfs_roc_drain() fix a race with open
  pNFS: Fix races between return-on-close and layoutreturn.
  pNFS: pnfs_roc_drain should return 'true' when sleeping
  pNFS: Layoutreturn must invalidate all existing layout segments.
  ...
2015-07-28 09:37:44 -07:00
Trond Myklebust
f580dd0428 SUNRPC: Report TCP errors to the caller
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-07-27 17:56:57 -04:00
NeilBrown
743c69e7c0 sunrpc: translate -EAGAIN to -ENOBUFS when socket is writable.
The networking layer does not reliably report the distinction between
a non-block write failing because:
 1/ the queue is too full already and
 2/ a memory allocation attempt failed.

The distinction is important because in the first case it is
appropriate to retry as soon as the socket reports that it is
writable, and in the second case a small delay is required as the
socket will most likely report as writable but kmalloc could still
fail.

sk_stream_wait_memory() exhibits this distinction nicely, setting
'vm_wait' if a small wait is needed.  However in the non-blocking case
it always returns -EAGAIN no matter the cause of the failure.  This
-EAGAIN call get all the way to sunrpc.

The sunrpc layer expects EAGAIN to indicate the first cause, and
ENOBUFS to indicate the second.  Various documentation suggests that
this is not unreasonable, but does not guarantee the desired error
codes.

The result of getting -EAGAIN when -ENOBUFS is expected is that the
send is tried again in a tight loop and soft lockups are reported.

so: add tests after calls to xs_sendpages() to translate -EAGAIN into
-ENOBUFS if the socket is writable.  This cannot happen inside
xs_sendpages() as the test for "is socket writable" is different
between TCP and UDP.

With this change, the tight loop retrying xs_sendpages() becomes a
loop which only retries every 250ms, and so will not trigger a
soft-lockup warning.

It is possible that the write did fail because the queue was too full
and by the time xs_sendpages() completed, the queue was writable
again.  In this case an extra 250ms delay is inserted that isn't
really needed.  This circumstance suggests a degree of congestion so a
delay is not necessarily a bad thing, and it can only cause a single
250ms delay, not a series of them.

Signed-off-by: NeilBrown <neilb@suse.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-07-27 11:16:56 -04:00
Trond Myklebust
b5872f0c67 SUNRPC: Don't confuse ENOBUFS with a write_space issue
ENOBUFS means that memory allocations are failing due to an actual
low memory situation. It should not be confused with being out of
socket buffer space.

Handle the problem by just punting to the delay in call_status.

Reported-by: Neil Brown <neilb@suse.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-07-03 09:42:54 -04:00
Linus Torvalds
8688d9540c NFS client updates for Linux 4.2
Highlights include:
 
 Stable patches:
 - Fix a crash in the NFSv4 file locking code.
 - Fix an fsync() regression, where we were failing to retry I/O in some
   circumstances.
 - Fix an infinite loop in NFSv4.0 OPEN stateid recovery
 - Fix a memory leak when an attempted pnfs fails.
 - Fix a memory leak in the backchannel code
 - Large hostnames were not supported correctly in NFSv4.1
 - Fix a pNFS/flexfiles bug that was impeding error reporting on I/O.
 - Fix a couple of credential issues in pNFS/flexfiles
 
 Bugfixes + cleanups:
 - Open flag sanity checks in the NFSv4 atomic open codepath
 - More NFSv4 delegation related bugfixes
 - Various NFSv4.1 backchannel bugfixes and cleanups
 - Fix the NFS swap socket code
 - Various cleanups of the NFSv4 SETCLIENTID and EXCHANGE_ID code
 - Fix a UDP transport deadlock issue
 
 Features:
 - More RDMA client transport improvements
 - NFSv4.2 LAYOUTSTATS functionality for pnfs flexfiles.
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Merge tag 'nfs-for-4.2-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs

Pull NFS client updates from Trond Myklebust:
 "Highlights include:

  Stable patches:
   - Fix a crash in the NFSv4 file locking code.
   - Fix an fsync() regression, where we were failing to retry I/O in
     some circumstances.
   - Fix an infinite loop in NFSv4.0 OPEN stateid recovery
   - Fix a memory leak when an attempted pnfs fails.
   - Fix a memory leak in the backchannel code
   - Large hostnames were not supported correctly in NFSv4.1
   - Fix a pNFS/flexfiles bug that was impeding error reporting on I/O.
   - Fix a couple of credential issues in pNFS/flexfiles

  Bugfixes + cleanups:
   - Open flag sanity checks in the NFSv4 atomic open codepath
   - More NFSv4 delegation related bugfixes
   - Various NFSv4.1 backchannel bugfixes and cleanups
   - Fix the NFS swap socket code
   - Various cleanups of the NFSv4 SETCLIENTID and EXCHANGE_ID code
   - Fix a UDP transport deadlock issue

  Features:
   - More RDMA client transport improvements
   - NFSv4.2 LAYOUTSTATS functionality for pnfs flexfiles"

* tag 'nfs-for-4.2-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs: (87 commits)
  nfs: Remove invalid tk_pid from debug message
  nfs: Remove invalid NFS_ATTR_FATTR_V4_REFERRAL checking in nfs4_get_rootfh
  nfs: Drop bad comment in nfs41_walk_client_list()
  nfs: Remove unneeded micro checking of CONFIG_PROC_FS
  nfs: Don't setting FILE_CREATED flags always
  nfs: Use remove_proc_subtree() instead remove_proc_entry()
  nfs: Remove unused argument in nfs_server_set_fsinfo()
  nfs: Fix a memory leak when meeting an unsupported state protect
  nfs: take extra reference to fl->fl_file when running a LOCKU operation
  NFSv4: When returning a delegation, don't reclaim an incompatible open mode.
  NFSv4.2: LAYOUTSTATS is optional to implement
  NFSv4.2: Fix up a decoding error in layoutstats
  pNFS/flexfiles: Fix the reset of struct pgio_header when resending
  pNFS/flexfiles: Turn off layoutcommit for servers that don't need it
  pnfs/flexfiles: protect ktime manipulation with mirror lock
  nfs: provide pnfs_report_layoutstat when NFS42 is disabled
  nfs: verify open flags before allowing open
  nfs: always update creds in mirror, even when we have an already connected ds
  nfs: fix potential credential leak in ff_layout_update_mirror_cred
  pnfs/flexfiles: report layoutstat regularly
  ...
2015-07-02 11:32:23 -07:00
Trond Myklebust
775f06ab49 SUNRPC: Set the TCP user timeout option on client sockets
Use the TCP_USER_TIMEOUT socket option to advertise to the server
how long we will keep the connection open if there is unacknowledged
data. See RFC5482.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-06-20 15:31:54 -04:00
Trond Myklebust
4876cc779f SUNRPC: Ensure we release the TCP socket once it has been closed
This fixes a regression introduced by commit caf4ccd4e8 ("SUNRPC:
Make xs_tcp_close() do a socket shutdown rather than a sock_release").
Prior to that commit, the autoclose feature would ensure that an
idle connection would result in the socket being both disconnected and
released, whereas now only gets disconnected.

While the current behaviour is harmless, it does leave the port bound
until either RPC traffic resumes or the RPC client is shut down.

Reported-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-06-19 19:20:12 -04:00
Chuck Lever
4a06825839 SUNRPC: Transport fault injection
It has been exceptionally useful to exercise the logic that handles
local immediate errors and RDMA connection loss.  To enable
developers to test this regularly and repeatably, add logic to
simulate connection loss every so often.

Fault injection is disabled by default. It is enabled with

  $ sudo echo xxx > /sys/kernel/debug/sunrpc/inject_fault/disconnect

where "xxx" is a large positive number of transport method calls
before a disconnect. A value of several thousand is usually a good
number that allows reasonable forward progress while still causing a
lot of connection drops.

These hooks are disabled when SUNRPC_DEBUG is turned off.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-06-10 18:37:26 -04:00
Jeff Layton
d67fa4d85a sunrpc: turn swapper_enable/disable functions into rpc_xprt_ops
RDMA xprts don't have a sock_xprt, but an rdma_xprt, so the
xs_swapper_enable/disable functions will likely oops when fed an RDMA
xprt. Turn these functions into rpc_xprt_ops so that that doesn't
occur. For now the RDMA versions are no-ops that just return -EINVAL
on an attempt to swapon.

Cc: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Jeff Layton <jeff.layton@primarydata.com>
Reviewed-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-06-10 18:26:26 -04:00
Jeff Layton
d6e971d8ec sunrpc: lock xprt before trying to set memalloc on the sockets
It's possible that we could race with a call to xs_reset_transport, in
which case the xprt->inet pointer could be zeroed out while we're
accessing it. Lock the xprt before we try to set memalloc on it.

Cc: Mel Gorman <mgorman@suse.de>
Signed-off-by: Jeff Layton <jeff.layton@primarydata.com>
Reviewed-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-06-10 18:26:24 -04:00
Jeff Layton
264d1df3b3 sunrpc: if we're closing down a socket, clear memalloc on it first
We currently increment the memalloc_socks counter if we have a xprt that
is associated with a swapfile. That socket can be replaced however
during a reconnect event, and the memalloc_socks counter is never
decremented if that occurs.

When tearing down a xprt socket, check to see if the xprt is set up for
swapping and sk_clear_memalloc before releasing the socket if so.

Acked-by: Mel Gorman <mgorman@suse.de>
Signed-off-by: Jeff Layton <jeff.layton@primarydata.com>
Reviewed-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-06-10 18:26:22 -04:00
Jeff Layton
8e2281330f sunrpc: make xprt->swapper an atomic_t
Split xs_swapper into enable/disable functions and eliminate the
"enable" flag.

Currently, it's racy if you have multiple swapon/swapoff operations
running in parallel over the same xprt. Also fix it so that we only
set it to a memalloc socket on a 0->1 transition and only clear it
on a 1->0 transition.

Cc: Mel Gorman <mgorman@suse.de>
Signed-off-by: Jeff Layton <jeff.layton@primarydata.com>
Reviewed-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-06-10 18:26:18 -04:00
Jeff Layton
3c87ef6efb sunrpc: keep a count of swapfiles associated with the rpc_clnt
Jerome reported seeing a warning pop when working with a swapfile on
NFS. The nfs_swap_activate can end up calling sk_set_memalloc while
holding the rcu_read_lock and that function can sleep.

To fix that, we need to take a reference to the xprt while holding the
rcu_read_lock, set the socket up for swapping and then drop that
reference. But, xprt_put is not exported and having NFS deal with the
underlying xprt is a bit of layering violation anyway.

Fix this by adding a set of activate/deactivate functions that take a
rpc_clnt pointer instead of an rpc_xprt, and have nfs_swap_activate and
nfs_swap_deactivate call those.

Also, add a per-rpc_clnt atomic counter to keep track of the number of
active swapfiles associated with it. When the counter does a 0->1
transition, we enable swapping on the xprt, when we do a 1->0 transition
we disable swapping on it.

This also allows us to be a bit more selective with the RPC_TASK_SWAPPER
flag. If non-swapper and swapper clnts are sharing a xprt, then we only
need to flag the tasks from the swapper clnt with that flag.

Acked-by: Mel Gorman <mgorman@suse.de>
Reported-by: Jerome Marchand <jmarchan@redhat.com>
Signed-off-by: Jeff Layton <jeff.layton@primarydata.com>
Reviewed-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-06-10 18:26:14 -04:00
Stefan Hajnoczi
9300fdba25 SUNRPC: drop stale doc comments in xprtsock.c
Several functions have outdated arguments listed in the doc comments.
Drop documentation for arguments that no longer exist.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-06-02 08:55:28 -04:00
Luis R. Rodriguez
9c27847dda kernel/params: constify struct kernel_param_ops uses
Most code already uses consts for the struct kernel_param_ops,
sweep the kernel for the last offending stragglers. Other than
include/linux/moduleparam.h and kernel/params.c all other changes
were generated with the following Coccinelle SmPL patch. Merge
conflicts between trees can be handled with Coccinelle.

In the future git could get Coccinelle merge support to deal with
patch --> fail --> grammar --> Coccinelle --> new patch conflicts
automatically for us on patches where the grammar is available and
the patch is of high confidence. Consider this a feature request.

Test compiled on x86_64 against:

	* allnoconfig
	* allmodconfig
	* allyesconfig

@ const_found @
identifier ops;
@@

const struct kernel_param_ops ops = {
};

@ const_not_found depends on !const_found @
identifier ops;
@@

-struct kernel_param_ops ops = {
+const struct kernel_param_ops ops = {
};

Generated-by: Coccinelle SmPL
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Junio C Hamano <gitster@pobox.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Kees Cook <keescook@chromium.org>
Cc: Tejun Heo <tj@kernel.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: cocci@systeme.lip6.fr
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Luis R. Rodriguez <mcgrof@suse.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2015-05-28 11:32:10 +09:30
Trond Myklebust
c627d31ba0 SUNRPC: Cleanup to remove xs_tcp_close()
xs_tcp_close() is now just a call to xs_tcp_shutdown(), so remove it,
and replace the entry in xs_tcp_ops.

Suggested-by: Anna Schumaker <anna.schumaker@netapp.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-02-10 11:06:04 -05:00
Trond Myklebust
402e23b4ed SUNRPC: Fix stupid typo in xs_sock_set_reuseport
Yes, kernel_setsockopt() hates you for using a char argument.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-02-09 17:31:02 -05:00
Trond Myklebust
54c0987492 SUNRPC: Define xs_tcp_fin_timeout only if CONFIG_SUNRPC_DEBUG
Now that the linger code is gone, the xs_tcp_fin_timeout variable has
no real function. Keep it for now, since it is part of the /proc
interface, but only define it if that /proc interface is enabled.

Suggested-by: Anna Schumaker <Anna.Schumaker@netapp.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-02-09 11:27:45 -05:00
Trond Myklebust
b70ae915e4 SUNRPC: Handle connection reset more efficiently.
If the connection reset is due to an active call on our side, then
the state change is sometimes not reported. Catch those instances
using xs_error_report() instead.
Also remove the xs_tcp_shutdown() call in xs_tcp_send_request() as
the change in behaviour makes it redundant.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-02-09 11:27:42 -05:00
Trond Myklebust
9e2b9f3776 SUNRPC: Remove the redundant XPRT_CONNECTION_CLOSE flag
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-02-09 11:26:06 -05:00
Trond Myklebust
caf4ccd4e8 SUNRPC: Make xs_tcp_close() do a socket shutdown rather than a sock_release
Use of socket shutdown() means that we monitor the shutdown process
through the xs_tcp_state_change() callback, so it is preferable to
a full close in all cases unless we're destroying the transport.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-02-09 11:20:44 -05:00
Trond Myklebust
0efeac261c SUNRPC: Ensure xs_tcp_shutdown() requests a full close of the connection
The previous behaviour left the connection half-open in order to try
to scrape the last replies from the socket. Now that we have more reliable
reconnection, change the behaviour to close down the socket faster.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-02-09 09:31:11 -05:00
Trond Myklebust
505936f59f SUNRPC: Cleanup to remove remaining uses of XPRT_CONNECTION_ABORT
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-02-09 09:20:40 -05:00
Trond Myklebust
9cbc94fb06 SUNRPC: Remove TCP socket linger code
Now that we no longer use the partial shutdown code when closing the
socket, we no longer need to worry about the TCP linger2 state.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-02-09 09:20:40 -05:00
Trond Myklebust
4efdd92c92 SUNRPC: Remove TCP client connection reset hack
Instead we rely on SO_REUSEPORT to provide the reconnection semantics
that we need for NFSv2/v3.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-02-08 21:47:30 -05:00
Trond Myklebust
de84d89030 SUNRPC: TCP/UDP always close the old socket before reconnecting
It is not safe to call xs_reset_transport() from inside xs_udp_setup_socket()
or xs_tcp_setup_socket(), since they do not own the correct locks. Instead,
do it in xs_connect().

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-02-08 21:47:30 -05:00
Trond Myklebust
718ba5b873 SUNRPC: Add helpers to prevent socket create from racing
The socket lock is currently held by the task that is requesting the
connection be established. While that is efficient in the case where
the connection happens quickly, it is racy in the case where it doesn't.
What we really want is for the connect helper to be able to block access
to the socket while it is being set up.

This patch does so by arranging to transfer the socket lock from the
task that is requesting the connect attempt, and then releasing that
lock once everything is done.
This scheme also gives us automatic protection against collisions with
the RPC close code, so we can kill the cancel_delayed_work_sync()
call in xs_close().

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-02-08 21:47:29 -05:00
Trond Myklebust
6cc7e90836 SUNRPC: Ensure xs_reset_transport() resets the close connection flags
Otherwise, we may end up looping.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-02-08 21:47:28 -05:00
Trond Myklebust
76698b2358 SUNRPC: Do not clear the source port in xs_reset_transport
Now that we can reuse bound ports after a close, we never really want to
clear the transport's source port after it has been set. Doing so really
messes up the NFSv3 DRC on the server.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-02-08 21:47:28 -05:00
Trond Myklebust
3913c78c3a SUNRPC: Handle EADDRINUSE on connect
Now that we're setting SO_REUSEPORT, we still need to handle the
case where a connect() is attempted, but the old socket is still
lingering.
Essentially, all we want to do here is handle the error by waiting
a few seconds and then retrying.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-02-08 21:47:27 -05:00
Trond Myklebust
4dda9c8a5e SUNRPC: Set SO_REUSEPORT socket option for TCP connections
When using TCP, we need the ability to reuse port numbers after
a disconnection, so that the NFSv3 server knows that we're the same
client. Currently we use a hack to work around the TCP socket's
TIME_WAIT: we send an RST instead of closing, which doesn't
always work...
The SO_REUSEPORT option added in Linux 3.9 allows us to bind multiple
TCP connections to the same source address+port combination, and thus
to use ordinary TCP close() instead of the current hack.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-02-08 18:52:11 -05:00
Jeff Layton
f895b252d4 sunrpc: eliminate RPC_DEBUG
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>
2014-11-24 17:31:46 -05:00
Jeff Layton
1a867a0898 sunrpc: add tracepoints in xs_tcp_data_recv
Add tracepoints inside the main loop on xs_tcp_data_recv that allow
us to keep an eye on what's happening during each phase of it.

Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2014-11-24 12:53:35 -05:00
Jeff Layton
3705ad64f1 sunrpc: add new tracepoints in xprt handling code
...so we can keep track of when calls are sent and replies received.

Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2014-11-24 12:53:35 -05:00
NeilBrown
1aff525629 NFS/SUNRPC: Remove other deadlock-avoidance mechanisms in nfs_release_page()
Now that nfs_release_page() doesn't block indefinitely, other deadlock
avoidance mechanisms aren't needed.
 - it doesn't hurt for kswapd to block occasionally.  If it doesn't
   want to block it would clear __GFP_WAIT.  The current_is_kswapd()
   was only added to avoid deadlocks and we have a new approach for
   that.
 - memory allocation in the SUNRPC layer can very rarely try to
   ->releasepage() a page it is trying to handle.  The deadlock
   is removed as nfs_release_page() doesn't block indefinitely.

So we don't need to set PF_FSTRANS for sunrpc network operations any
more.

Signed-off-by: NeilBrown <neilb@suse.de>
Acked-by: Jeff Layton <jlayton@primarydata.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2014-09-25 08:25:47 -04:00