Commit Graph

144 Commits

Author SHA1 Message Date
Linus Torvalds
42e1b14b6e Merge branch 'locking-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull locking updates from Ingo Molnar:
 "The main changes in this cycle were:

   - Implement wraparound-safe refcount_t and kref_t types based on
     generic atomic primitives (Peter Zijlstra)

   - Improve and fix the ww_mutex code (Nicolai Hähnle)

   - Add self-tests to the ww_mutex code (Chris Wilson)

   - Optimize percpu-rwsems with the 'rcuwait' mechanism (Davidlohr
     Bueso)

   - Micro-optimize the current-task logic all around the core kernel
     (Davidlohr Bueso)

   - Tidy up after recent optimizations: remove stale code and APIs,
     clean up the code (Waiman Long)

   - ... plus misc fixes, updates and cleanups"

* 'locking-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (50 commits)
  fork: Fix task_struct alignment
  locking/spinlock/debug: Remove spinlock lockup detection code
  lockdep: Fix incorrect condition to print bug msgs for MAX_LOCKDEP_CHAIN_HLOCKS
  lkdtm: Convert to refcount_t testing
  kref: Implement 'struct kref' using refcount_t
  refcount_t: Introduce a special purpose refcount type
  sched/wake_q: Clarify queue reinit comment
  sched/wait, rcuwait: Fix typo in comment
  locking/mutex: Fix lockdep_assert_held() fail
  locking/rtmutex: Flip unlikely() branch to likely() in __rt_mutex_slowlock()
  locking/rwsem: Reinit wake_q after use
  locking/rwsem: Remove unnecessary atomic_long_t casts
  jump_labels: Move header guard #endif down where it belongs
  locking/atomic, kref: Implement kref_put_lock()
  locking/ww_mutex: Turn off __must_check for now
  locking/atomic, kref: Avoid more abuse
  locking/atomic, kref: Use kref_get_unless_zero() more
  locking/atomic, kref: Kill kref_sub()
  locking/atomic, kref: Add kref_read()
  locking/atomic, kref: Add KREF_INIT()
  ...
2017-02-20 13:23:30 -08:00
Peter Zijlstra
2c935bc572 locking/atomic, kref: Add kref_read()
Since we need to change the implementation, stop exposing internals.

Provide kref_read() to read the current reference count; typically
used for debug messages.

Kills two anti-patterns:

	atomic_read(&kref->refcount)
	kref->refcount.counter

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-01-14 11:37:18 +01:00
Scott Mayhew
546125d161 sunrpc: don't call sleeping functions from the notifier block callbacks
The inet6addr_chain is an atomic notifier chain, so we can't call
anything that might sleep (like lock_sock)... instead of closing the
socket from svc_age_temp_xprts_now (which is called by the notifier
function), just have the rpc service threads do it instead.

Cc: stable@vger.kernel.org
Fixes: c3d4879e01 "sunrpc: Add a function to close..."
Signed-off-by: Scott Mayhew <smayhew@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2017-01-12 15:56:40 -05:00
Scott Mayhew
ea08e39230 sunrpc: svc_age_temp_xprts_now should not call setsockopt non-tcp transports
This fixes the following panic that can occur with NFSoRDMA.

general protection fault: 0000 [#1] SMP
Modules linked in: rpcrdma ib_isert iscsi_target_mod ib_iser libiscsi
scsi_transport_iscsi ib_srpt target_core_mod ib_srp scsi_transport_srp
scsi_tgt ib_ipoib rdma_ucm ib_ucm ib_uverbs ib_umad rdma_cm ib_cm iw_cm
mlx5_ib ib_core intel_powerclamp coretemp kvm_intel kvm sg ioatdma
ipmi_devintf ipmi_ssif dcdbas iTCO_wdt iTCO_vendor_support pcspkr
irqbypass sb_edac shpchp dca crc32_pclmul ghash_clmulni_intel edac_core
lpc_ich aesni_intel lrw gf128mul glue_helper ablk_helper mei_me mei
ipmi_si cryptd wmi ipmi_msghandler acpi_pad acpi_power_meter nfsd
auth_rpcgss nfs_acl lockd grace sunrpc ip_tables xfs libcrc32c sd_mod
crc_t10dif crct10dif_generic mgag200 i2c_algo_bit drm_kms_helper
syscopyarea sysfillrect sysimgblt ahci fb_sys_fops ttm libahci mlx5_core
tg3 crct10dif_pclmul drm crct10dif_common
ptp i2c_core libata crc32c_intel pps_core fjes dm_mirror dm_region_hash
dm_log dm_mod
CPU: 1 PID: 120 Comm: kworker/1:1 Not tainted 3.10.0-514.el7.x86_64 #1
Hardware name: Dell Inc. PowerEdge R320/0KM5PX, BIOS 2.4.2 01/29/2015
Workqueue: events check_lifetime
task: ffff88031f506dd0 ti: ffff88031f584000 task.ti: ffff88031f584000
RIP: 0010:[<ffffffff8168d847>]  [<ffffffff8168d847>]
_raw_spin_lock_bh+0x17/0x50
RSP: 0018:ffff88031f587ba8  EFLAGS: 00010206
RAX: 0000000000020000 RBX: 20041fac02080072 RCX: ffff88031f587fd8
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 20041fac02080072
RBP: ffff88031f587bb0 R08: 0000000000000008 R09: ffffffff8155be77
R10: ffff880322a59b00 R11: ffffea000bf39f00 R12: 20041fac02080072
R13: 000000000000000d R14: ffff8800c4fbd800 R15: 0000000000000001
FS:  0000000000000000(0000) GS:ffff880322a40000(0000)
knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f3c52d4547e CR3: 00000000019ba000 CR4: 00000000001407e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Stack:
20041fac02080002 ffff88031f587bd0 ffffffff81557830 20041fac02080002
ffff88031f587c78 ffff88031f587c40 ffffffff8155ae08 000000010157df32
0000000800000001 ffff88031f587c20 ffffffff81096acb ffffffff81aa37d0
Call Trace:
[<ffffffff81557830>] lock_sock_nested+0x20/0x50
[<ffffffff8155ae08>] sock_setsockopt+0x78/0x940
[<ffffffff81096acb>] ? lock_timer_base.isra.33+0x2b/0x50
[<ffffffff8155397d>] kernel_setsockopt+0x4d/0x50
[<ffffffffa0386284>] svc_age_temp_xprts_now+0x174/0x1e0 [sunrpc]
[<ffffffffa03b681d>] nfsd_inetaddr_event+0x9d/0xd0 [nfsd]
[<ffffffff81691ebc>] notifier_call_chain+0x4c/0x70
[<ffffffff810b687d>] __blocking_notifier_call_chain+0x4d/0x70
[<ffffffff810b68b6>] blocking_notifier_call_chain+0x16/0x20
[<ffffffff815e8538>] __inet_del_ifa+0x168/0x2d0
[<ffffffff815e8cef>] check_lifetime+0x25f/0x270
[<ffffffff810a7f3b>] process_one_work+0x17b/0x470
[<ffffffff810a8d76>] worker_thread+0x126/0x410
[<ffffffff810a8c50>] ? rescuer_thread+0x460/0x460
[<ffffffff810b052f>] kthread+0xcf/0xe0
[<ffffffff810b0460>] ? kthread_create_on_node+0x140/0x140
[<ffffffff81696418>] ret_from_fork+0x58/0x90
[<ffffffff810b0460>] ? kthread_create_on_node+0x140/0x140
Code: ca 75 f1 5d c3 0f 1f 80 00 00 00 00 eb d9 66 0f 1f 44 00 00 0f 1f
44 00 00 55 48 89 e5 53 48 89 fb e8 7e 04 a0 ff b8 00 00 02 00 <f0> 0f
c1 03 89 c2 c1 ea 10 66 39 c2 75 03 5b 5d c3 83 e2 fe 0f
RIP  [<ffffffff8168d847>] _raw_spin_lock_bh+0x17/0x50
RSP <ffff88031f587ba8>

Signed-off-by: Scott Mayhew <smayhew@redhat.com>
Fixes: c3d4879e ("sunrpc: Add a function to close temporary transports immediately")
Reviewed-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2016-11-14 10:30:58 -05:00
Trond Myklebust
f4a4906e56 SUNRPC: Remove unused callback xpo_adjust_wspace()
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2016-07-13 15:53:50 -04:00
Trond Myklebust
ff3ac5c3dc SUNRPC: Add a server side per-connection limit
Allow the user to limit the number of requests serviced through a single
connection, to help prevent faster clients from starving slower clients.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2016-07-13 15:53:48 -04:00
Trond Myklebust
104f6351f7 SUNRPC: Add tracepoints for dropped and deferred requests
Dropping and/or deferring requests has an impact on performance. Let's
make sure we can trace those events.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2016-07-13 15:53:43 -04:00
Trond Myklebust
82ea2d7615 SUNRPC: Add a tracepoint for server socket out-of-space conditions
Add a tracepoint to track when the processing of incoming RPC data gets
deferred due to out-of-space issues on the outgoing transport.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2016-07-13 15:53:42 -04:00
J. Bruce Fields
39a9beab5a rpc: share one xps between all backchannels
The spec allows backchannels for multiple clients to share the same tcp
connection.  When that happens, we need to use the same xprt for all of
them.  Similarly, we need the same xps.

This fixes list corruption introduced by the multipath code.

Cc: stable@vger.kernel.org
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Acked-by: Trond Myklebust <trondmy@primarydata.com>
2016-06-15 10:32:25 -04:00
J. Bruce Fields
d96b9c9398 svcrpc: autoload rdma module
This should fix failures like:

	# rpc.nfsd --rdma
	rpc.nfsd: Unable to request RDMA services: Protocol not supported

Reported-by: Steve Dickson <steved@redhat.com>
Reviewed-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2016-05-23 10:55:24 -04:00
Scott Mayhew
c3d4879e01 sunrpc: Add a function to close temporary transports immediately
Add a function svc_age_temp_xprts_now() to close temporary transports
whose xpt_local matches the address passed in server_addr immediately
instead of waiting for them to be closed by the timer function.

The function is intended to be used by notifier_blocks that will be
added to nfsd and lockd that will run when an ip address is deleted.

This will eliminate the ACK storms and client hangs that occur in
HA-NFS configurations where nfsd & lockd is left running on the cluster
nodes all the time and the NFS 'service' is migrated back and forth
within a short timeframe.

Signed-off-by: Scott Mayhew <smayhew@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2015-12-23 10:08:15 -05:00
Jeff Layton
b9e13cdfac nfsd/sunrpc: turn enqueueing a svc_xprt into a svc_serv operation
For now, all services use svc_xprt_do_enqueue, but once we add
workqueue-based service support, we'll need to do something different.

Signed-off-by: Shirley Ma <shirley.ma@oracle.com>
Acked-by: Jeff Layton <jlayton@primarydata.com>
Tested-by: Shirley Ma <shirley.ma@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2015-08-10 16:05:42 -04:00
Jeff Layton
3c5199143b sunrpc/lockd: fix references to the BKL
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>
2015-01-23 10:29:12 -05:00
Jeff Layton
acf06a7fa1 sunrpc: only call test_bit once in svc_xprt_received
...move the WARN_ON_ONCE inside the following if block since they use
the same condition.

Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2014-12-09 11:29:14 -05:00
Jeff Layton
83a712e0af sunrpc: add some tracepoints around enqueue and dequeue of svc_xprt
These were useful when I was tracking down a race condition between
svc_xprt_do_enqueue and svc_get_next_xprt.

Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2014-12-09 11:29:14 -05:00
Jeff Layton
b1691bc03d sunrpc: convert to lockless lookup of queued server threads
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>
2014-12-09 11:22:22 -05:00
Jeff Layton
403c7b4444 sunrpc: fix potential races in pool_stats collection
In a later patch, we'll be removing some spinlocking around the socket
and thread queueing code in order to fix some contention problems. At
that point, the stats counters will no longer be protected by the
sp_lock.

Change the counters to atomic_long_t fields, except for the
"sockets_queued" counter which will still be manipulated under a
spinlock.

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>
2014-12-09 11:22:22 -05:00
Jeff Layton
ceff739c53 sunrpc: have svc_wake_up only deal with pool 0
The way that svc_wake_up works is a bit inefficient. It walks all of the
available pools for a service and either wakes up a task in each one or
sets the SP_TASK_PENDING flag in each one.

When svc_wake_up is called, there is no need to wake up more than one
thread to do this work. In practice, only lockd currently uses this
function and it's single threaded anyway. Thus, this just boils down to
doing a wake up of a thread in pool 0 or setting a single flag.

Eliminate the for loop in this function and change it to just operate on
pool 0. Also update the comments that sit above it and get rid of some
code that has been commented out for years now.

Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2014-12-09 11:22:21 -05:00
Jeff Layton
4d5db3f536 sunrpc: convert sp_task_pending flag to use atomic bitops
In a later patch, we'll want to be able to handle this flag without
holding the sp_lock. Change this field to an unsigned long flags
field, and declare a new flag in it that can be managed with atomic
bitops.

Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2014-12-09 11:22:21 -05:00
Jeff Layton
78b65eb3fd sunrpc: move rq_dropme flag into rq_flags
Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2014-12-09 11:22:20 -05:00
Jeff Layton
30660e04b0 sunrpc: move rq_usedeferral flag to rq_flags
Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2014-12-09 11:22:20 -05:00
Jeff Layton
4d152e2c9a sunrpc: add a generic rq_flags field to svc_rqst and move rq_secure to it
In a later patch, we're going to need some atomic bit flags. Since that
field will need to be an unsigned long, we mitigate that space
consumption by migrating some other bitflags to the new field. Start
with the rq_secure flag.

Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2014-12-09 11:21:20 -05:00
J. Bruce Fields
2941b0e91b NFS client updates for Linux 3.19
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
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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.
2014-12-09 11:12:26 -05:00
Jeff Layton
8d65ef760d sunrpc: eliminate the XPT_DETACHED flag
All it does is indicate whether a xprt has already been deleted from
a list or not, which is unnecessary since we use list_del_init and it's
always set and checked under the sv_lock anyway.

Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2014-12-01 12:45:26 -07:00
Jeff Layton
860a0d9e51 sunrpc: add some tracepoints in svc_rqst handling functions
...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>
2014-11-24 12:53:34 -05:00
J. Bruce Fields
ae89254da6 SUNRPC: Fix compile on non-x86
current_task appears to be x86-only, oops.

Let's just delete this check entirely:

Any developer that adds a new user without setting rq_task will get a
crash the first time they test it.  I also don't think there are
normally any important locks held here, and I can't see any other reason
why killing a server thread would bring the whole box down.

So the effort to fail gracefully here looks like overkill.

Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Fixes: 983c684466 "SUNRPC: get rid of the request wait queue"
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2014-08-28 15:51:35 -04:00
Trond Myklebust
0c0746d03e SUNRPC: More optimisations of svc_xprt_enqueue()
Just move the transport locking out of the spin lock protected area
altogether.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2014-08-17 12:00:11 -04:00
Trond Myklebust
a4aa8054a6 SUNRPC: Fix broken kthread_should_stop test in svc_get_next_xprt
We should definitely not be exiting svc_get_next_xprt() with the
thread enqueued. Fix this by ensuring that we fall through to
the dequeue.
Also move the test itself outside the spin lock protected section.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2014-08-17 12:00:11 -04:00
Trond Myklebust
983c684466 SUNRPC: get rid of the request wait queue
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>
2014-08-17 12:00:11 -04:00
Trond Myklebust
106f359cf4 SUNRPC: Do not grab pool->sp_lock unnecessarily in svc_get_next_xprt
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2014-08-17 12:00:10 -04:00
Trond Myklebust
9e5b208dc9 SUNRPC: Do not override wspace tests in svc_handle_xprt
We already determined that there was enough wspace when we
called svc_xprt_enqueue.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2014-08-17 12:00:10 -04:00
Trond Myklebust
518776800c SUNRPC: Allow svc_reserve() to notify TCP socket that space has been freed
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2014-07-29 16:10:20 -04:00
Trond Myklebust
0971374e28 SUNRPC: Reduce contention in svc_xprt_enqueue()
Ensure that all calls to svc_xprt_enqueue() except svc_xprt_received()
check the value of XPT_BUSY, before attempting to grab spinlocks etc.
This is to avoid situations such as the following "perf" trace,
which shows heavy contention on the pool spinlock:

    54.15%            nfsd  [kernel.kallsyms]        [k] _raw_spin_lock_bh
                      |
                      --- _raw_spin_lock_bh
                         |
                         |--71.43%-- svc_xprt_enqueue
                         |          |
                         |          |--50.31%-- svc_reserve
                         |          |
                         |          |--31.35%-- svc_xprt_received
                         |          |
                         |          |--18.34%-- svc_tcp_data_ready
...

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2014-07-29 16:10:15 -04:00
J. Bruce Fields
2825a7f907 nfsd4: allow encoding across page boundaries
After this we can handle for example getattr of very large ACLs.

Read, readdir, readlink are still special cases with their own limits.

Also we can't handle a new operation starting close to the end of a
page.

Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2014-05-30 17:31:54 -04:00
Trond Myklebust
c789102c20 SUNRPC: Fix a module reference leak in svc_handle_xprt
If the accept() call fails, we need to put the module reference.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Cc: stable@vger.kernel.org
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2014-05-22 15:57:22 -04:00
Chuck Lever
16e4d93f6d NFSD: Ignore client's source port on RDMA transports
An NFS/RDMA client's source port is meaningless for RDMA transports.
The transport layer typically sets the source port value on the
connection to a random ephemeral port.

Currently, NFS server administrators must specify the "insecure"
export option to enable clients to access exports via RDMA.

But this means NFS clients can access such an export via IP using an
ephemeral port, which may not be desirable.

This patch eliminates the need to specify the "insecure" export
option to allow NFS/RDMA clients access to an export.

BugLink: https://bugzilla.linux-nfs.org/show_bug.cgi?id=250
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2014-05-22 15:55:48 -04:00
Rashika Kheria
e1d83ee673 net: Mark functions as static in net/sunrpc/svc_xprt.c
Mark functions as static in net/sunrpc/svc_xprt.c because they are not
used outside this file.

This eliminates the following warning in net/sunrpc/svc_xprt.c:
net/sunrpc/svc_xprt.c:574:5: warning: no previous prototype for ‘svc_alloc_arg’ [-Wmissing-prototypes]
net/sunrpc/svc_xprt.c:615:18: warning: no previous prototype for ‘svc_get_next_xprt’ [-Wmissing-prototypes]
net/sunrpc/svc_xprt.c:694:6: warning: no previous prototype for ‘svc_add_new_temp_xprt’ [-Wmissing-prototypes]

Signed-off-by: Rashika Kheria <rashika.kheria@gmail.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-02-09 17:32:50 -08:00
J. Bruce Fields
cc630d9f47 svcrpc: fix rpc server shutdown races
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>
2013-02-17 10:53:51 -05:00
J. Bruce Fields
e75bafbff2 svcrpc: make svc_age_temp_xprts enqueue under sv_lock
svc_age_temp_xprts expires xprts in a two-step process: first it takes
the sv_lock and moves the xprts to expire off their server-wide list
(sv_tempsocks or sv_permsocks) to a local list.  Then it drops the
sv_lock and enqueues and puts each one.

I see no reason for this: svc_xprt_enqueue() will take sp_lock, but the
sv_lock and sp_lock are not otherwise nested anywhere (and documentation
at the top of this file claims it's correct to nest these with sp_lock
inside.)

Cc: stable@kernel.org
Tested-by: Jason Tibbitts <tibbs@math.uh.edu>
Tested-by: Paweł Sikora <pawel.sikora@agmk.net>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2013-02-17 10:53:16 -05:00
Andriy Skulysh
35525b7978 sunrpc: Fix lockd sleeping until timeout
There is a race in enqueueing thread to a pool and
waking up a thread.
lockd doesn't wake up on reception of lock granted callback
if svc_wake_up() is called before lockd's thread is added
to a pool.

Signed-off-by: Andriy Skulysh <Andriy_Skulysh@xyratex.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2013-01-23 18:17:39 -05:00
Weston Andros Adamson
0104729807 SUNRPC: remove BUG_ON in svc_delete_xprt
Replace BUG_ON() with WARN_ON_ONCE().

Signed-off-by: Weston Andros Adamson <dros@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-11-04 14:43:42 -05:00
Weston Andros Adamson
b25cd058f2 SUNRPC: remove BUG_ONs checking RPCSVC_MAXPAGES
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>
2012-11-04 14:43:41 -05:00
Weston Andros Adamson
ff1fdb9b80 SUNRPC: remove BUG_ON in svc_xprt_received
Replace BUG_ON() with a WARN_ON_ONCE() and early return.

Signed-off-by: Weston Andros Adamson <dros@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-11-04 14:43:41 -05:00
J. Bruce Fields
65b2e6656b svcrpc: split up svc_handle_xprt
Move initialization of newly accepted socket into a helper.

Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2012-08-21 17:42:02 -04:00
J. Bruce Fields
6797fa5a01 svcrpc: break up svc_recv
Matter of taste, I suppose, but svc_recv breaks up naturally into:

	allocate pages and setup arg
	dequeue (wait for, if necessary) next socket
	do something with that socket

And I find it easier to read when it doesn't go on for pages and pages.

Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2012-08-21 17:42:01 -04:00
J. Bruce Fields
6741019c82 svcrpc: make svc_xprt_received static
Note this isn't used outside svc_xprt.c.

May as well move it so we don't need a declaration while we're here.

Also remove an outdated comment.

Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2012-08-21 17:42:01 -04:00
J. Bruce Fields
9f9d2ebe69 svcrpc: make xpo_recvfrom return only >=0
The only errors returned from xpo_recvfrom have been -EAGAIN and
-EAFNOSUPPORT.  The latter was removed by a previous patch.  That leaves
only -EAGAIN, which is treated just like 0 by the caller (svc_recv).

So, just ditch -EAGAIN and return 0 instead.

Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2012-08-21 17:41:07 -04:00
J. Bruce Fields
39b5530137 svcrpc: share some setup of listening sockets
There's some duplicate code here.

Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2012-08-21 17:07:48 -04:00
J. Bruce Fields
c334196694 svcrpc: make svc_create_xprt enqueue on clearing XPT_BUSY
Whenever we clear XPT_BUSY we should call svc_xprt_enqueue().  Without
that we may fail to notice any events (such as new connections) that
arrived while XPT_BUSY was set.

Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2012-08-21 17:07:36 -04:00
J. Bruce Fields
719f8bcc88 svcrpc: fix xpt_list traversal locking on shutdown
Server threads are not running at this point, but svc_age_temp_xprts
still may be, so we need this locking.

Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2012-08-21 14:08:40 -04:00