Commit Graph

411 Commits

Author SHA1 Message Date
NeilBrown a534ecb013 NFSv4: add cl_root_cred for use when machine cred is not available.
NFSv4 state management tries a root credential when no machine
credential is available, as can happen with kerberos.
It does this by replacing the cl_machine_cred with a root credential.
This means that any user of the machine credential needs to take
a lock while getting a reference to the machine credential, which is
a little cumbersome.

So introduce an explicit cl_root_cred, and never free either
credential until client shutdown.  This means that no locking
is needed to reference these credentials.  Future patches
will make use of this.

This is only a temporary addition.  both cl_machine_cred and
cl_root_cred will disappear later in the series.

Signed-off-by: NeilBrown <neilb@suse.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2018-12-19 13:52:45 -05:00
Trond Myklebust aeabb3c961 NFSv4: Fix a NFSv4 state manager deadlock
Fix a deadlock whereby the NFSv4 state manager can get stuck in the
delegation return code, waiting for a layout return to complete in
another thread. If the server reboots before that other thread
completes, then we need to be able to start a second state
manager thread in order to perform recovery.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2018-11-19 20:11:45 -05:00
Trond Myklebust a1aa09be21 NFSv4: Ensure that the state manager exits the loop on SIGKILL
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2018-11-12 16:39:13 -05:00
Trond Myklebust 21a446cf18 NFSv4: Don't exit the state manager without clearing NFS4CLNT_MANAGER_RUNNING
If we exit the NFSv4 state manager due to a umount, then we can end up
leaving the NFS4CLNT_MANAGER_RUNNING flag set. If another mount causes
the nfs4_client to be rereferenced before it is destroyed, then we end
up never being able to recover state.

Fixes: 47c2199b6e ("NFSv4.1: Ensure state manager thread dies on last ...")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Cc: stable@vger.kernel.org # v4.15+
2018-11-12 16:39:13 -05:00
Anna Schumaker 80f4236886 NFSv4: Split out NFS v4.2 copy completion functions
The convention in the rest of the code is to have a separate function
for anything that might be ifdef-ed out.

Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2018-09-30 15:35:17 -04:00
Anna Schumaker 000d3f9566 NFS: Reduce indentation of nfs4_recovery_handle_error()
This is to match kernel coding style for switch statements.

Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2018-09-30 15:35:17 -04:00
Anna Schumaker 35a61606a6 NFS: Reduce indentation of the switch statement in nfs4_reclaim_open_state()
Most places in the kernel tend to line up cases with the switch to
reduce indentation, so move this over to match that style.
Additionally, I handle the (status >= 0) case in the switch so that we
only "goto restart" from a single place after error handling.

Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2018-09-30 15:35:17 -04:00
Anna Schumaker cb7a8384dc NFS: Split out the body of nfs4_reclaim_open_state()
Moving all of this into a new function removes the need for cramped
indentation, making the code overall easier to look at.   I also take
this chance to switch copy recovery over to using
nfs4_stateid_match_other()

Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2018-09-30 15:35:17 -04:00
Trond Myklebust ace9fad43a NFSv4: Convert struct nfs4_state to use refcount_t
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2018-09-30 15:35:17 -04:00
Trond Myklebust 9ae075fdd1 NFSv4: Convert open state lookup to use RCU
Further reduce contention on the inode->i_lock.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2018-09-30 15:35:17 -04:00
Trond Myklebust 0de43976fb NFS: Convert lookups of the open context to RCU
Reduce contention on the inode->i_lock by ensuring that we use RCU
when looking up the NFS open context.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2018-09-30 15:35:17 -04:00
Trond Myklebust 994b15b983 NFSv4.1 fix infinite loop on I/O.
The previous fix broke recovery of delegated stateids because it assumes
that if we did not mark the delegation as suspect, then the delegation has
effectively been revoked, and so it removes that delegation irrespectively
of whether or not it is valid and still in use. While this is "mostly
harmless" for ordinary I/O, we've seen pNFS fail with LAYOUTGET spinning
in an infinite loop while complaining that we're using an invalid stateid
(in this case the all-zero stateid).

What we rather want to do here is ensure that the delegation is always
correctly marked as needing testing when that is the case. So we want
to close the loophole offered by nfs4_schedule_stateid_recovery(),
which marks the state as needing to be reclaimed, but not the
delegation that may be backing it.

Fixes: 0e3d3e5df0 ("NFSv4.1 fix infinite loop on IO BAD_STATEID error")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Cc: stable@vger.kernel.org # v4.11+
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2018-09-14 16:24:11 -04:00
Trond Myklebust 8aafd2fde3 NFSv4: Don't busy wait if NFSv4 session draining is interrupted
Catch the ERESTARTSYS error so that it can be processed by the callers.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2018-08-13 17:23:37 -04:00
Olga Kornievskaia e4648aa4f9 NFS recover from destination server reboot for copies
Mark the destination state to indicate a server-side copy is
happening. On detecting a reboot and recovering open state check
if any state is engaged in a server-side copy, if so, find the
copy and mark it and then signal the waiting thread. Upon wakeup,
if copy was marked then propage EAGAIN to the nfsd_copy_file_range
and restart the copy from scratch.

Signed-off-by: Olga Kornievskaia <kolga@netapp.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2018-08-13 17:04:23 -04:00
Gustavo A. R. Silva 01e03bdc74 NFS: Mark expected switch fall-throughs
In preparation to enabling -Wimplicit-fallthrough, mark switch cases
where we are expecting to fall through.

Warning level 2 was used: -Wimplicit-fallthrough=2

Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2018-08-08 16:50:02 -04:00
Fred Isaman 2409a976a2 pnfs: Add LAYOUTGET to OPEN of a new file
This triggers when have no pre-existing inode to attach to.
The preexisting case is saved for later.

Signed-off-by: Fred Isaman <fred.isaman@gmail.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2018-05-31 15:03:11 -04:00
Matthew Wilcox aae5730e2d nfs: Use ida_simple API
Allocate the owner_id when we allocate the state and free it when we free
the state.  That lets us get rid of a gnarly ida_pre_get() / ida_get_new()
loop.

Signed-off-by: Matthew Wilcox <mawilcox@microsoft.com>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2018-04-10 16:06:22 -04:00
NeilBrown dce2630c7d NFSv4: always set NFS_LOCK_LOST when a lock is lost.
There are 2 comments in the NFSv4 code which suggest that
SIGLOST should possibly be sent to a process.  In these
cases a lock has been lost.
The current practice is to set NFS_LOCK_LOST so that
read/write returns EIO when a lock is lost.
So change these comments to code when sets NFS_LOCK_LOST.

One case is when lock recovery after apparent server restart
fails with NFS4ERR_DENIED, NFS4ERR_RECLAIM_BAD, or
NFS4ERRO_RECLAIM_CONFLICT.  The other case is when a lock
attempt as part of lease recovery fails with NFS4ERR_DENIED.

In an ideal world, these should not happen.  However I have
a packet trace showing an NFSv4.1 session getting
NFS4ERR_BADSESSION after an extended network parition.  The
NFSv4.1 client treats this like server reboot until/unless
it get NFS4ERR_NO_GRACE, in which case it switches over to
"nograce" recovery mode.  In this network trace, the client
attempts to recover a lock and the server (incorrectly)
reports NFS4ERR_DENIED rather than NFS4ERR_NO_GRACE.  This
leads to the ineffective comment and the client then
continues to write using the OPEN stateid.

Signed-off-by: NeilBrown <neilb@suse.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2018-01-14 23:06:29 -05:00
Trond Myklebust 445f288d70 NFSv4: Ensure gcc 4.4.4 can compile initialiser for "invalid_stateid"
gcc 4.4.4 is too old to have full C11 anonymous union support, so
the current initialiser fails to compile.

Reported-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
(compile-)Tested-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Reviewed-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2017-11-29 13:46:32 -05:00
Trond Myklebust fcd8843c40 NFSv4: Replace closed stateids with the "invalid special stateid"
When decoding a CLOSE, replace the stateid returned by the server
with the "invalid special stateid" described in RFC5661, Section 8.2.3.

In nfs_set_open_stateid_locked, ignore stateids from closed state.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2017-11-17 16:43:49 -05:00
Trond Myklebust 46280d9d3d NFSv4: Check the open stateid when searching for expired state
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2017-11-17 16:43:49 -05:00
Trond Myklebust c82bac6f4b NFSv4: Don't try to CLOSE if the stateid 'other' field has changed
If the stateid is no longer recognised on the server, either due to a
restart, or due to a competing CLOSE call, then we do not have to
retry. Any open contexts that triggered a reopen of the file, will
also act as triggers for any CLOSE for the updated stateids.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2017-11-17 16:43:47 -05:00
Trond Myklebust 12f275cdd1 NFSv4: Retry CLOSE and DELEGRETURN on NFS4ERR_OLD_STATEID.
If we're racing with an OPEN, then retry the operation instead of
declaring it a success.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
[Andrew W Elble: Fix a typo in nfs4_refresh_open_stateid]
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2017-11-17 16:43:47 -05:00
Trond Myklebust c9399f21c2 NFSv4: Fix OPEN / CLOSE race
Ben Coddington has noted the following race between OPEN and CLOSE
on a single client.

Process 1		Process 2		Server
=========		=========		======

1)  OPEN file
2)			OPEN file
3)						Process OPEN (1) seqid=1
4)						Process OPEN (2) seqid=2
5)						Reply OPEN (2)
6)			Receive reply (2)
7)			new stateid, seqid=2

8)			CLOSE file, using
			stateid w/ seqid=2
9)						Reply OPEN (1)
10(						Process CLOSE (8)
11)						Reply CLOSE (8)
12)						Forget stateid
						file closed

13)			Receive reply (7)
14)			Forget stateid
			file closed.

15) Receive reply (1).
16) New stateid seqid=1
    is really the same
    stateid that was
    closed.

IOW: the reply to the first OPEN is delayed. Since "Process 2" does
not wait before closing the file, and it does not cache the closed
stateid, then when the delayed reply is finally received, it is treated
as setting up a new stateid by the client.

The fix is to ensure that the client processes the OPEN and CLOSE calls
in the same order in which the server processed them.

This commit ensures that we examine the seqid of the stateid
returned by OPEN. If it is a new stateid, we assume the seqid
must be equal to the value 1, and that each state transition
increments the seqid value by 1 (See RFC7530, Section 9.1.4.2,
and RFC5661, Section 8.2.2).

If the tracker sees that an OPEN returns with a seqid that is greater
than the cached seqid + 1, then it bumps a flag to ensure that the
caller waits for the RPCs carrying the missing seqids to complete.

Note that there can still be pathologies where the server crashes before
it can even send us the missing seqids. Since the OPEN call is still
holding a slot when it waits here, that could cause the recovery to
stall forever. To avoid that, we time out after a 5 second wait.

Reported-by: Benjamin Coddington <bcodding@redhat.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2017-11-17 16:43:45 -05:00
Elena Reshetova 212bf41d88 fs, nfs: convert nfs_client.cl_count from atomic_t to refcount_t
atomic_t variables are currently used to implement reference
counters with the following properties:
 - counter is initialized to 1 using atomic_set()
 - a resource is freed upon counter reaching zero
 - once counter reaches zero, its further
   increments aren't allowed
 - counter schema uses basic atomic operations
   (set, inc, inc_not_zero, dec_and_test, etc.)

Such atomic variables should be converted to a newly provided
refcount_t type and API that prevents accidental counter overflows
and underflows. This is important since overflows and underflows
can lead to use-after-free situation and be exploitable.

The variable nfs_client.cl_count is used as pure reference counter.
Convert it to refcount_t and fix up the operations.

Suggested-by: Kees Cook <keescook@chromium.org>
Reviewed-by: David Windsor <dwindsor@gmail.com>
Reviewed-by: Hans Liljestrand <ishkamiel@gmail.com>
Signed-off-by: Elena Reshetova <elena.reshetova@intel.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2017-11-17 13:48:01 -05:00
Elena Reshetova 194bc1f481 fs, nfs: convert nfs4_lock_state.ls_count from atomic_t to refcount_t
atomic_t variables are currently used to implement reference
counters with the following properties:
 - counter is initialized to 1 using atomic_set()
 - a resource is freed upon counter reaching zero
 - once counter reaches zero, its further
   increments aren't allowed
 - counter schema uses basic atomic operations
   (set, inc, inc_not_zero, dec_and_test, etc.)

Such atomic variables should be converted to a newly provided
refcount_t type and API that prevents accidental counter overflows
and underflows. This is important since overflows and underflows
can lead to use-after-free situation and be exploitable.

The variable nfs4_lock_state.ls_count  is used as pure reference counter.
Convert it to refcount_t and fix up the operations.

Suggested-by: Kees Cook <keescook@chromium.org>
Reviewed-by: David Windsor <dwindsor@gmail.com>
Reviewed-by: Hans Liljestrand <ishkamiel@gmail.com>
Signed-off-by: Elena Reshetova <elena.reshetova@intel.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2017-11-17 13:48:00 -05:00
Linus Torvalds b86faee6d1 NFS client updates for Linux 4.13
Stable bugfixes:
 - Fix -EACCESS on commit to DS handling
 - Fix initialization of nfs_page_array->npages
 - Only invalidate dentries that are actually invalid
 
 Features:
 - Enable NFSoRDMA transparent state migration
 - Add support for lookup-by-filehandle
 - Add support for nfs re-exporting
 
 Other bugfixes and cleanups:
 - Christoph cleaned up the way we declare NFS operations
 - Clean up various internal structures
 - Various cleanups to commits
 - Various improvements to error handling
 - Set the dt_type of . and .. entries in NFS v4
 - Make slot allocation more reliable
 - Fix fscache stat printing
 - Fix uninitialized variable warnings
 - Fix potential list overrun in nfs_atomic_open()
 - Fix a race in NFSoRDMA RPC reply handler
 - Fix return size for nfs42_proc_copy()
 - Fix against MAC forgery timing attacks
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Merge tag 'nfs-for-4.13-1' of git://git.linux-nfs.org/projects/anna/linux-nfs

Pull NFS client updates from Anna Schumaker:
 "Stable bugfixes:
   - Fix -EACCESS on commit to DS handling
   - Fix initialization of nfs_page_array->npages
   - Only invalidate dentries that are actually invalid

  Features:
   - Enable NFSoRDMA transparent state migration
   - Add support for lookup-by-filehandle
   - Add support for nfs re-exporting

  Other bugfixes and cleanups:
   - Christoph cleaned up the way we declare NFS operations
   - Clean up various internal structures
   - Various cleanups to commits
   - Various improvements to error handling
   - Set the dt_type of . and .. entries in NFS v4
   - Make slot allocation more reliable
   - Fix fscache stat printing
   - Fix uninitialized variable warnings
   - Fix potential list overrun in nfs_atomic_open()
   - Fix a race in NFSoRDMA RPC reply handler
   - Fix return size for nfs42_proc_copy()
   - Fix against MAC forgery timing attacks"

* tag 'nfs-for-4.13-1' of git://git.linux-nfs.org/projects/anna/linux-nfs: (68 commits)
  NFS: Don't run wake_up_bit() when nobody is waiting...
  nfs: add export operations
  nfs4: add NFSv4 LOOKUPP handlers
  nfs: add a nfs_ilookup helper
  nfs: replace d_add with d_splice_alias in atomic_open
  sunrpc: use constant time memory comparison for mac
  NFSv4.2 fix size storage for nfs42_proc_copy
  xprtrdma: Fix documenting comments in frwr_ops.c
  xprtrdma: Replace PAGE_MASK with offset_in_page()
  xprtrdma: FMR does not need list_del_init()
  xprtrdma: Demote "connect" log messages
  NFSv4.1: Use seqid returned by EXCHANGE_ID after state migration
  NFSv4.1: Handle EXCHGID4_FLAG_CONFIRMED_R during NFSv4.1 migration
  xprtrdma: Don't defer MR recovery if ro_map fails
  xprtrdma: Fix FRWR invalidation error recovery
  xprtrdma: Fix client lock-up after application signal fires
  xprtrdma: Rename rpcrdma_req::rl_free
  xprtrdma: Pass only the list of registered MRs to ro_unmap_sync
  xprtrdma: Pre-mark remotely invalidated MRs
  xprtrdma: On invalidation failure, remove MWs from rl_registered
  ...
2017-07-13 14:35:37 -07:00
Chuck Lever 8dcbec6d20 NFSv4.1: Handle EXCHGID4_FLAG_CONFIRMED_R during NFSv4.1 migration
Transparent State Migration copies a client's lease state from the
server where a filesystem used to reside to the server where it now
resides. When an NFSv4.1 client first contacts that destination
server, it uses EXCHANGE_ID to detect trunking relationships.

The lease that was copied there is returned to that client, but the
destination server sets EXCHGID4_FLAG_CONFIRMED_R when replying to
the client. This is because the lease was confirmed on the source
server (before it was copied).

Normally, when CONFIRMED_R is set, a client purges the lease and
creates a new one. However, that throws away the entire benefit of
Transparent State Migration.

Therefore, the client must not purge that lease when it is possible
that Transparent State Migration has occurred.

Reported-by: Xuan Qi <xuan.qi@oracle.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Tested-by: Xuan Qi <xuan.qi@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2017-07-13 16:00:12 -04:00
Trond Myklebust 898fc11bb2 NFS: Trunking detection should handle ERESTARTSYS/EINTR
Currently, it will return EIO in those cases.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2017-06-27 21:44:58 -04:00
Trond Myklebust 0048fdd066 NFSv4.1: RECLAIM_COMPLETE must handle NFS4ERR_CONN_NOT_BOUND_TO_SESSION
If the server returns NFS4ERR_CONN_NOT_BOUND_TO_SESSION because we
are trunking, then RECLAIM_COMPLETE must handle that by calling
nfs4_schedule_session_recovery() and then retrying.

Reported-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Tested-by: Chuck Lever <chuck.lever@oracle.com>
2017-05-05 12:01:50 -04:00
Wei Yongjun 68e33bd6bb NFSv4: Fix warning for using 0 as NULL
Fixes the following sparse warning:

fs/nfs/nfs4state.c:862:60: warning: Using plain integer as NULL pointer

Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2017-01-30 13:14:51 -05:00
Chuck Lever 406dab8450 nfs: Fix "Don't increment lock sequence ID after NFS4ERR_MOVED"
Lock sequence IDs are bumped in decode_lock by calling
nfs_increment_seqid(). nfs_increment_sequid() does not use the
seqid_mutating_err() function fixed in commit 059aa73482 ("Don't
increment lock sequence ID after NFS4ERR_MOVED").

Fixes: 059aa73482 ("Don't increment lock sequence ID after ...")
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Tested-by: Xuan Qi <xuan.qi@oracle.com>
Cc: stable@vger.kernel.org # v3.7+
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2017-01-26 15:25:03 -05:00
Trond Myklebust c6180a6237 NFSv4: Fix client recovery when server reboots multiple times
If the server reboots multiple times, the client should rely on the
server to tell it that it cannot reclaim state as per section 9.6.3.4
in RFC7530 and section 8.4.2.1 in RFC5661.
Currently, the client is being to conservative, and is assuming that
if the server reboots while state recovery is in progress, then it must
ignore state that was not recovered before the reboot.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2017-01-13 13:31:32 -05:00
NeilBrown 86cfb04185 NFS: Don't disconnect open-owner on NFS4ERR_BAD_SEQID
When an NFS4ERR_BAD_SEQID is received the open-owner is removed from
the ->state_owners rbtree so that it will no longer be used.

If any stateids attached to this open-owner are still in use, and if a
request using one gets an NFS4ERR_BAD_STATEID reply, this can for bad.

The state is marked as needing recovery and the nfs4_state_manager()
is scheduled to clean up.  nfs4_state_manager() finds states to be
recovered by walking the state_owners rbtree.  As the open-owner is
not in the rbtree, the bad state is not found so nfs4_state_manager()
completes having done nothing.  The request is then retried, with a
predicatable result (indefinite retries).

If the stateid is for a delegation, this open_owner will be used
to open files when the delegation is returned.  For that to work,
a new open-owner needs to be presented to the server.

This patch changes NFS4ERR_BAD_SEQID handling to leave the open-owner
in the rbtree but updates the 'create_time' so it looks like a new
open-owner.  With this the indefinite retries no longer happen.

Signed-off-by: NeilBrown <neilb@suse.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2016-12-19 17:29:51 -05:00
NeilBrown 3f8f25489f NFSv4: ensure __nfs4_find_lock_state returns consistent result.
If a file has both flock locks and OFD locks, then it is possible that
two different nfs4 lock states could apply to file accesses from a
single process.

It is not possible to know, efficiently, which one is "correct".
Presumably the state which represents a lock that covers the region
undergoing IO would be the "correct" one to use, but finding that has
a non-trivial cost and would provide miniscule value.

Currently we just return whichever is first in the list, which could
result in inconsistent behaviour if an application ever put it self in
this position.  As consistent behaviour is preferable (when perfectly
correct behaviour is not available), change the search to return a
consistent result in this circumstance.
Specifically: if there is both a flock and OFD lock state, always return
the flock one.

Reviewed-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: NeilBrown <neilb@suse.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2016-12-19 17:29:50 -05:00
Trond Myklebust d94cbf6c73 NFSv4.1: Don't schedule lease recovery in nfs4_schedule_session_recovery()
If the session has an error, then we want to start by recovering the
session, as any SEQUENCE we send is going to fail with a session
error.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2016-12-04 19:34:38 -05:00
NeilBrown d51fdb87a6 NFS: discard nfs_lockowner structure.
It now has only one field and is only used in one structure.
So replaced it in that structure by the field it contains.

Signed-off-by: NeilBrown <neilb@suse.com>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2016-12-01 17:58:13 -05:00
NeilBrown 8d42443166 NFSv4: enhance nfs4_copy_lock_stateid to use a flock stateid if there is one
A process can have two possible lock owner for a given open file:
a per-process Posix lock owner and a per-open-file flock owner
Use both of these when searching for a suitable stateid to use.

With this patch, READ/WRITE requests will use the correct stateid
if a flock lock is active.

Signed-off-by: NeilBrown <neilb@suse.com>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2016-12-01 17:58:05 -05:00
NeilBrown 1739347549 NFSv4: change nfs4_select_rw_stateid to take a lock_context inplace of lock_owner
The only time that a lock_context is not immediately available is in
setattr, and now that it has an open_context, it can easily find one
with nfs_get_lock_context.
This removes the need for the on-stack nfs_lockowner.

This change is preparation for correctly support flock stateids.

Signed-off-by: NeilBrown <neilb@suse.com>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2016-12-01 17:57:56 -05:00
Benjamin Coddington d41cbfc9a6 NFSv4.1: Handle NFS4ERR_OLD_STATEID in nfs4_reclaim_open_state
Now that we're doing TEST_STATEID in nfs4_reclaim_open_state(), we can have
a NFS4ERR_OLD_STATEID returned from nfs41_open_expired() .  Instead of
marking state recovery as failed, mark the state for recovery again.

Signed-off-by: Benjamin Coddington <bcodding@redhat.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2016-11-18 14:27:27 -05:00
Trond Myklebust 7ebeb7fe74 NFSv4: If recovery failed for a specific open stateid, then don't retry
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Tested-by: Oleg Drokin <green@linuxhacker.ru>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2016-09-27 14:35:27 -04:00
Trond Myklebust 304020fe48 NFSv4: Open state recovery must account for file permission changes
If the file permissions change on the server, then we may not be able to
recover open state. If so, we need to ensure that we mark the file
descriptor appropriately.

Cc: stable@vger.kernel.org
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Tested-by: Oleg Drokin <green@linuxhacker.ru>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2016-09-27 14:35:19 -04:00
Trond Myklebust 6c2d8f8d30 NFSv4: nfs_inode_find_state_and_recover() should check all stateids
Modify the helper nfs_inode_find_state_and_recover() so that it
can check all open/lock/delegation state trackers on that inode for
whether or not they need are affected by a revoked stateid error.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Tested-by: Oleg Drokin <green@linuxhacker.ru>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2016-09-27 14:34:35 -04:00
Trond Myklebust 45870d6909 NFSv4.1: Test delegation stateids when server declares "some state revoked"
According to RFC5661, if any of the SEQUENCE status bits
SEQ4_STATUS_EXPIRED_ALL_STATE_REVOKED,
SEQ4_STATUS_EXPIRED_SOME_STATE_REVOKED, SEQ4_STATUS_ADMIN_STATE_REVOKED,
or SEQ4_STATUS_RECALLABLE_STATE_REVOKED are set, then we need to use
TEST_STATEID to figure out which stateids have been revoked, so we
can acknowledge the loss of state using FREE_STATEID.

While we already do this for open and lock state, we have not been doing
so for all the delegations.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Tested-by: Oleg Drokin <green@linuxhacker.ru>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2016-09-27 14:33:44 -04:00
Trond Myklebust 0a014a44a5 NFSv4.1: Don't deadlock the state manager on the SEQUENCE status flags
As described in RFC5661, section 18.46, some of the status flags exist
in order to tell the client when it needs to acknowledge the existence of
revoked state on the server and/or to recover state.
Those flags will then remain set until the recovery procedure is done.

In order to avoid looping, the client therefore needs to ignore
those particular flags while recovering.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Tested-by: Oleg Drokin <green@linuxhacker.ru>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2016-09-27 14:31:27 -04:00
Trond Myklebust fb10fb67ad NFSv4: Cleanup the setting of the nfs4 lease period
Make a helper function nfs4_set_lease_period() and have
nfs41_setup_state_renewal() and nfs4_do_fsinfo() use it.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2016-08-05 19:13:08 -04:00
Oleg Drokin cea7f829d3 nfs4: Fix potential use after free of state in nfs4_do_reclaim.
Commit e8d975e73e ("fixing infinite OPEN loop in 4.0 stateid recovery")
introduced access to state after it was just potentially freed by
nfs4_put_open_state leading to a random data corruption somewhere.

BUG: unable to handle kernel paging request at ffff88004941ee40
IP: [<ffffffff813baf01>] nfs4_do_reclaim+0x461/0x740
PGD 3501067 PUD 3504067 PMD 6ff37067 PTE 800000004941e060
Oops: 0002 [#1] SMP DEBUG_PAGEALLOC
Modules linked in: loop rpcsec_gss_krb5 acpi_cpufreq tpm_tis joydev i2c_piix4 pcspkr tpm virtio_console nfsd ttm drm_kms_helper syscopyarea sysfillrect sysimgblt fb_sys_fops floppy serio_raw virtio_blk drm
CPU: 6 PID: 2161 Comm: 192.168.10.253- Not tainted 4.7.0-rc1-vm-nfs+ #112
Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
task: ffff8800463dcd00 ti: ffff88003ff48000 task.ti: ffff88003ff48000
RIP: 0010:[<ffffffff813baf01>]  [<ffffffff813baf01>] nfs4_do_reclaim+0x461/0x740
RSP: 0018:ffff88003ff4bd68  EFLAGS: 00010246
RAX: 0000000000000000 RBX: ffffffff81a49900 RCX: 00000000000000e8
RDX: 00000000000000e8 RSI: ffff8800418b9930 RDI: ffff880040c96c88
RBP: ffff88003ff4bdf8 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: ffff880040c96c98
R13: ffff88004941ee20 R14: ffff88004941ee40 R15: ffff88004941ee00
FS:  0000000000000000(0000) GS:ffff88006d000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffff88004941ee40 CR3: 0000000060b0b000 CR4: 00000000000006e0
Stack:
 ffffffff813baad5 ffff8800463dcd00 ffff880000000001 ffffffff810e6b68
 ffff880043ddbc88 ffff8800418b9800 ffff8800418b98c8 ffff88004941ee48
 ffff880040c96c90 ffff880040c96c00 ffff880040c96c20 ffff880040c96c40
Call Trace:
 [<ffffffff813baad5>] ? nfs4_do_reclaim+0x35/0x740
 [<ffffffff810e6b68>] ? trace_hardirqs_on_caller+0x128/0x1b0
 [<ffffffff813bb7cd>] nfs4_run_state_manager+0x5ed/0xa40
 [<ffffffff813bb1e0>] ? nfs4_do_reclaim+0x740/0x740
 [<ffffffff813bb1e0>] ? nfs4_do_reclaim+0x740/0x740
 [<ffffffff810af0d1>] kthread+0x101/0x120
 [<ffffffff810e6b68>] ? trace_hardirqs_on_caller+0x128/0x1b0
 [<ffffffff818843af>] ret_from_fork+0x1f/0x40
 [<ffffffff810aefd0>] ? kthread_create_on_node+0x250/0x250
Code: 65 80 4c 8b b5 78 ff ff ff e8 fc 88 4c 00 48 8b 7d 88 e8 13 67 d2 ff 49 8b 47 40 a8 02 0f 84 d3 01 00 00 4c 89 ff e8 7f f9 ff ff <f0> 41 80 26 7f 48 8b 7d c8 e8 b1 84 4c 00 e9 39 fd ff ff 3d e6
RIP  [<ffffffff813baf01>] nfs4_do_reclaim+0x461/0x740
 RSP <ffff88003ff4bd68>
CR2: ffff88004941ee40

Signed-off-by: Oleg Drokin <green@linuxhacker.ru>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2016-06-24 12:01:00 -04:00
Linus Torvalds e0714ec4f9 nfs: fix anonymous member initializer build failure with older compilers
Older versions of gcc don't understand named initializers inside a
anonymous structure or union member.  It can be worked around by adding
the bracin gin the initializer for the anonymous member.

Without this, gcc 4.4.4 will fail the build with

    CC      fs/nfs/nfs4state.o
  fs/nfs/nfs4state.c:69: error: unknown field ‘data’ specified in initializer
  fs/nfs/nfs4state.c:69: warning: missing braces around initializer
  fs/nfs/nfs4state.c:69: warning: (near initialization for ‘zero_stateid.<anonymous>.data’)
  make[2]: *** [fs/nfs/nfs4state.o] Error 1

introduced in commit 93b717fd81 ("NFSv4: Label stateids with the type")

Reported-and-tested-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Anna Schumaker <Anna.Schumaker@netapp.com>
Cc: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-05-27 17:20:27 -07:00
Trond Myklebust abf4e13cc1 NFSv4: Use the right stateid for delegations in setattr, read and write
When we're using a delegation to represent our open state, we should
ensure that we use the stateid that was used to create that delegation.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2016-05-17 15:48:07 -04:00
Trond Myklebust 93b717fd81 NFSv4: Label stateids with the type
In order to more easily distinguish what kind of stateid we are dealing
with, introduce a type that can be used to label the stateid structure.

The label will be useful both for debugging, but also when dealing with
operations like SETATTR, READ and WRITE that can take several different
types of stateid as arguments.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2016-05-17 15:48:06 -04:00
Trond Myklebust 4a0954ef34 NFSv4: Don't try to reclaim unused state owners
Currently, we don't test if the state owner is in use before we try to
recover it. The problem is that if the refcount is zero, then the
state owner will be waiting on the lru list for garbage collection.
The expectation in that case is that if you bump the refcount, then
you must also remove the state owner from the lru list. Otherwise
the call to nfs4_put_state_owner will corrupt that list by trying
to add our state owner a second time.

Avoid the whole problem by just skipping state owners that hold no
state.

Reported-by: Andrew W Elble <aweits@rit.edu>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-10-02 15:43:07 -04:00
Olga Kornievskaia a41cbe86df Failing to send a CLOSE if file is opened WRONLY and server reboots on a 4.x mount
A test case is as the description says:
open(foobar, O_WRONLY);
sleep()  --> reboot the server
close(foobar)

The bug is because in nfs4state.c in nfs4_reclaim_open_state() a few
line before going to restart, there is
clear_bit(NFS4CLNT_RECLAIM_NOGRACE, &state->flags).

NFS4CLNT_RECLAIM_NOGRACE is a flag for the client states not open
owner states. Value of NFS4CLNT_RECLAIM_NOGRACE is 4 which is the
value of NFS_O_WRONLY_STATE in nfs4_state->flags. So clearing it wipes
out state and when we go to close it, “call_close” doesn’t get set as
state flag is not set and CLOSE doesn’t go on the wire.

Signed-off-by: Olga Kornievskaia <aglo@umich.edu>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-09-17 15:48:11 -04:00
Anna Schumaker 3f10a6af4b NFS: Remove nfs41_server_notify_{target|highest}_slotid_update()
All these functions do is call nfs41_ping_server() without adding
anything.  Let's remove them and give nfs41_ping_server() a better name
instead.

Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-08-17 13:32:00 -05:00
Trond Myklebust b13529059c NFSv4.1: Handle SEQ4_STATUS_BACKCHANNEL_FAULT correctly
RFC5661 states:

      The server has encountered an unrecoverable fault with the
      backchannel (e.g., it has lost track of the sequence ID for a slot
      in the backchannel).  The client MUST stop sending more requests
      on the session's fore channel, wait for all outstanding requests
      to complete on the fore and back channel, and then destroy the
      session.

Ensure we do so...

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-07-05 15:50:18 -04:00
Trond Myklebust 4099287feb NFSv4.1: Handle SEQ4_STATUS_RECALLABLE_STATE_REVOKED status bit correctly
Try to handle this for now by invalidating all outstanding layouts for this
server and then testing all the open+lock+delegation stateids.
At some later stage, we may want to optimise by separating out the testing of
delegation stateids only, and adding testing of layout stateids.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-07-05 15:50:18 -04:00
Trond Myklebust 8b895ce652 NFSv4.1: Handle SEQ4_STATUS_EXPIRED_SOME_STATE_REVOKED status bit correctly.
If the server tells us that only some state has been revoked, then we
need to run the full TEST_STATEID dog and pony show in order to discover
which locks and delegations are still OK. Currently we blow away all
state, which means that we lose all locks!

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-07-05 15:46:38 -04:00
Trond Myklebust 5cae02f427 NFSv4: Always drain the slot table before re-establishing the lease
While the NFSv4.1 code has always drained the slot tables in order to stop
non-recovery related RPC calls when doing lease recovery, the NFSv4 code
did not.
The reason for the difference in behaviour is that NFSv4 does not have
session state, and so RPC calls can in theory proceed while recovery is
happening. In practice, however, anything I/O or state related needs to
wait until recovery is over.

This patch changes the behaviour of NFSv4 to match that of NFSv4.1 so that
we can simplify the state recovery code by assuming that we do not have to
deal with races between recovery and ordinary I/O.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-06-02 08:55:27 -04:00
Olga Kornievskaia e8d975e73e fixing infinite OPEN loop in 4.0 stateid recovery
Problem: When an operation like WRITE receives a BAD_STATEID, even though
recovery code clears the RECLAIM_NOGRACE recovery flag before recovering
the open state, because of clearing delegation state for the associated
inode, nfs_inode_find_state_and_recover() gets called and it makes the
same state with RECLAIM_NOGRACE flag again. As a results, when we restart
looking over the open states, we end up in the infinite loop instead of
breaking out in the next test of state flags.

Solution: unset the RECLAIM_NOGRACE set because of
calling of nfs_inode_find_state_and_recover() after returning from calling
recover_open() function.

Signed-off-by: Olga Kornievskaia <kolga@netapp.com>
Cc: stable@vger.kernel.org
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-06-01 09:58:02 -04:00
Linus Torvalds 59953fba87 NFS client updates for Linux 4.1
Highlights include:
 
 Stable patches:
 - Fix a regression in /proc/self/mountstats
 - Fix the pNFS flexfiles O_DIRECT support
 - Fix high load average due to callback thread sleeping
 
 Bugfixes:
 - Various patches to fix the pNFS layoutcommit support
 - Do not cache pNFS deviceids unless server notifications are enabled
 - Fix a SUNRPC transport reconnection regression
 - make debugfs file creation failure non-fatal in SUNRPC
 - Another fix for circular directory warnings on NFSv4 "junctioned" mountpoints
 - Fix locking around NFSv4.2 fallocate() support
 - Truncating NFSv4 file opens should also sync O_DIRECT writes
 - Prevent infinite loop in rpcrdma_ep_create()
 
 Features:
 - Various improvements to the RDMA transport code's handling of memory
   registration
 - Various code cleanups
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Merge tag 'nfs-for-4.1-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs

Pull NFS client updates from Trond Myklebust:
 "Another set of mainly bugfixes and a couple of cleanups.  No new
  functionality in this round.

  Highlights include:

  Stable patches:
   - Fix a regression in /proc/self/mountstats
   - Fix the pNFS flexfiles O_DIRECT support
   - Fix high load average due to callback thread sleeping

  Bugfixes:
   - Various patches to fix the pNFS layoutcommit support
   - Do not cache pNFS deviceids unless server notifications are enabled
   - Fix a SUNRPC transport reconnection regression
   - make debugfs file creation failure non-fatal in SUNRPC
   - Another fix for circular directory warnings on NFSv4 "junctioned"
     mountpoints
   - Fix locking around NFSv4.2 fallocate() support
   - Truncating NFSv4 file opens should also sync O_DIRECT writes
   - Prevent infinite loop in rpcrdma_ep_create()

  Features:
   - Various improvements to the RDMA transport code's handling of
     memory registration
   - Various code cleanups"

* tag 'nfs-for-4.1-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs: (55 commits)
  fs/nfs: fix new compiler warning about boolean in switch
  nfs: Remove unneeded casts in nfs
  NFS: Don't attempt to decode missing directory entries
  Revert "nfs: replace nfs_add_stats with nfs_inc_stats when add one"
  NFS: Rename idmap.c to nfs4idmap.c
  NFS: Move nfs_idmap.h into fs/nfs/
  NFS: Remove CONFIG_NFS_V4 checks from nfs_idmap.h
  NFS: Add a stub for GETDEVICELIST
  nfs: remove WARN_ON_ONCE from nfs_direct_good_bytes
  nfs: fix DIO good bytes calculation
  nfs: Fetch MOUNTED_ON_FILEID when updating an inode
  sunrpc: make debugfs file creation failure non-fatal
  nfs: fix high load average due to callback thread sleeping
  NFS: Reduce time spent holding the i_mutex during fallocate()
  NFS: Don't zap caches on fallocate()
  xprtrdma: Make rpcrdma_{un}map_one() into inline functions
  xprtrdma: Handle non-SEND completions via a callout
  xprtrdma: Add "open" memreg op
  xprtrdma: Add "destroy MRs" memreg op
  xprtrdma: Add "reset MRs" memreg op
  ...
2015-04-26 17:33:59 -07:00
Anna Schumaker 40c64c26a4 NFS: Move nfs_idmap.h into fs/nfs/
This file is only used internally to the NFS v4 module, so it doesn't
need to be in the global include path.  I also renamed it from
nfs_idmap.h to nfs4idmap.h to emphasize that it's an NFSv4-only include
file.

Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-04-23 15:16:14 -04:00
David Howells 2b0143b5c9 VFS: normal filesystems (and lustre): d_inode() annotations
that's the bulk of filesystem drivers dealing with inodes of their own

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-04-15 15:06:57 -04:00
Trond Myklebust e11259f920 NFSv4.1: Clear the old state by our client id before establishing a new lease
If the call to exchange-id returns with the EXCHGID4_FLAG_CONFIRMED_R flag
set, then that means our lease was established by a previous mount instance.
Ensure that we detect this situation, and that we clear the state held by
that mount.

Reported-by: Jorge Mora <Jorge.Mora@netapp.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-03-03 21:52:30 -05:00
Trond Myklebust 48d66b9749 NFSv4: Fix a race in NFSv4.1 server trunking discovery
We do not want to allow a race with another NFS mount to cause
nfs41_walk_client_list() to establish a lease on our nfs_client before
we're done checking for trunking.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-03-03 20:42:23 -05:00
Linus Torvalds 6f83e5bd3e NFS client updates for Linux 3.20
Highlights incluse:
 
 Features:
 - Removing the forced serialisation of open()/close() calls in NFSv4.x (x>0)
   makes for a significant performance improvement in metadata intensive
   workloads.
 - Full support for the pNFS "flexible files" layout type
 - Further RPC/RDMA client improvements from Chuck
 
 Bugfixes:
 - Stable fix: NFSv4.1 backchannel calls blocking operations with !TASK_RUNNING
 - Stable fix: pnfs_generic_pg_init_read/write can be called with lseg == NULL
 - Stable fix: Fix an Oopsable condition when nsm_mon_unmon is called as part
   of the namespace cleanup,
 - Stable fix: Ensure we reference the inode for return-on-close in delegreturn
 
 - Use SO_REUSEPORT to ensure that NFSv3 TCP connections can rebind to the
   same source address/port combination during a disconnect/reconnect event.
   This is a requirement imposed by most NFSv3 server duplicate reply cache
   implementations.
 
 Optimisations:
 - Ask for no NFSv4.1 delegations on OPEN if using O_DIRECT
 
 Other:
 - Add Anna Schumaker as co-maintainer for the NFS client
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Merge tag 'nfs-for-3.20-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs

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

  Features:
   - Removing the forced serialisation of open()/close() calls in
     NFSv4.x (x>0) makes for a significant performance improvement in
     metadata intensive workloads.
   - Full support for the pNFS "flexible files" layout type
   - Further RPC/RDMA client improvements from Chuck

  Bugfixes:
   - Stable fix: NFSv4.1 backchannel calls blocking operations with !TASK_RUNNING
   - Stable fix: pnfs_generic_pg_init_read/write can be called with lseg == NULL
   - Stable fix: Fix an Oopsable condition when nsm_mon_unmon is called
     as part of the namespace cleanup,
   - Stable fix: Ensure we reference the inode for return-on-close in
     delegreturn
   - Use SO_REUSEPORT to ensure that NFSv3 TCP connections can rebind to
     the same source address/port combination during a disconnect/
     reconnect event.  This is a requirement imposed by most NFSv3
     server duplicate reply cache implementations.

  Optimisations:
   - Ask for no NFSv4.1 delegations on OPEN if using O_DIRECT

  Other:
   - Add Anna Schumaker as co-maintainer for the NFS client"

* tag 'nfs-for-3.20-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs: (119 commits)
  SUNRPC: Cleanup to remove xs_tcp_close()
  pnfs: delete an unintended goto
  pnfs/flexfiles: Do not dprintk after the free
  SUNRPC: Fix stupid typo in xs_sock_set_reuseport
  SUNRPC: Define xs_tcp_fin_timeout only if CONFIG_SUNRPC_DEBUG
  SUNRPC: Handle connection reset more efficiently.
  SUNRPC: Remove the redundant XPRT_CONNECTION_CLOSE flag
  SUNRPC: Make xs_tcp_close() do a socket shutdown rather than a sock_release
  SUNRPC: Ensure xs_tcp_shutdown() requests a full close of the connection
  SUNRPC: Cleanup to remove remaining uses of XPRT_CONNECTION_ABORT
  SUNRPC: Remove TCP socket linger code
  SUNRPC: Remove TCP client connection reset hack
  SUNRPC: TCP/UDP always close the old socket before reconnecting
  SUNRPC: Add helpers to prevent socket create from racing
  SUNRPC: Ensure xs_reset_transport() resets the close connection flags
  SUNRPC: Do not clear the source port in xs_reset_transport
  SUNRPC: Handle EADDRINUSE on connect
  SUNRPC: Set SO_REUSEPORT socket option for TCP connections
  NFSv4.1: Fix pnfs_put_lseg races
  NFSv4.1: pnfs_send_layoutreturn should use GFP_NOFS
  ...
2015-02-11 17:14:54 -08:00
Trond Myklebust a67964197c NFSv4: Check for NULL argument in nfs_*_seqid() functions
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-01-23 23:06:45 -05:00
Trond Myklebust badc76dd0d NFSv4: Convert nfs_alloc_seqid() to return an ERR_PTR() if allocation fails
When we relax the sequencing on the NFSv4.1 OPEN/CLOSE code, we will want
to use the value NULL to indicate that no sequencing is needed.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-01-23 23:06:44 -05:00
Jeff Layton 6109c85037 locks: add a dedicated spinlock to protect i_flctx lists
We can now add a dedicated spinlock without expanding struct inode.
Change to using that to protect the various i_flctx lists.

Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Acked-by: Christoph Hellwig <hch@lst.de>
2015-01-16 16:08:49 -05:00
Jeff Layton bd61e0a9c8 locks: convert posix locks to file_lock_context
Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Acked-by: Christoph Hellwig <hch@lst.de>
2015-01-16 16:08:16 -05:00
Jeff Layton 5263e31e45 locks: move flock locks to file_lock_context
Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Acked-by: Christoph Hellwig <hch@lst.de>
2015-01-16 15:09:25 -05:00
Trond Myklebust 72c23f0819 Merge branch 'bugfixes' into linux-next
* bugfixes:
  NFSv4.1: Fix an NFSv4.1 state renewal regression
  NFSv4: fix open/lock state recovery error handling
  NFSv4: Fix lock recovery when CREATE_SESSION/SETCLIENTID_CONFIRM fails
  NFS: Fabricate fscache server index key correctly
  SUNRPC: Add missing support for RPC_CLNT_CREATE_NO_RETRANS_TIMEOUT
  nfs: fix duplicate proc entries
2014-09-30 17:21:41 -04:00
Trond Myklebust df817ba357 NFSv4: fix open/lock state recovery error handling
The current open/lock state recovery unfortunately does not handle errors
such as NFS4ERR_CONN_NOT_BOUND_TO_SESSION correctly. Instead of looping,
just proceeds as if the state manager is finished recovering.
This patch ensures that we loop back, handle higher priority errors
and complete the open/lock state recovery.

Cc: stable@vger.kernel.org
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2014-09-28 16:03:04 -04:00
Trond Myklebust a4339b7b68 NFSv4: Fix lock recovery when CREATE_SESSION/SETCLIENTID_CONFIRM fails
If a NFSv4.x server returns NFS4ERR_STALE_CLIENTID in response to a
CREATE_SESSION or SETCLIENTID_CONFIRM in order to tell us that it rebooted
a second time, then the client will currently take this to mean that it must
declare all locks to be stale, and hence ineligible for reboot recovery.

RFC3530 and RFC5661 both suggest that the client should instead rely on the
server to respond to inelegible open share, lock and delegation reclaim
requests with NFS4ERR_NO_GRACE in this situation.

Cc: stable@vger.kernel.org
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2014-09-28 16:03:03 -04:00
Olga Kornievskaia 8faaa6d5d4 Fixing lease renewal
Commit c9fdeb28 removed a 'continue' after checking if the lease needs
to be renewed. However, if client hasn't moved, the code falls down to
starting reboot recovery erroneously (ie., sends open reclaim and gets
back stale_clientid error) before recovering from getting stale_clientid
on the renew operation.

Signed-off-by: Olga Kornievskaia <kolga@netapp.com>
Fixes: c9fdeb280b (NFS: Add basic migration support to state manager thread)
Cc: stable@vger.kernel.org # 3.13+
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2014-09-24 23:03:15 -04:00
Jeff Layton 0c0e0d3c09 nfs: revert "nfs4: queue free_lock_state job submission to nfsiod"
This reverts commit 49a4bda22e.

Christoph reported an oops due to the above commit:

generic/089 242s ...[ 2187.041239] general protection fault: 0000 [#1]
SMP
[ 2187.042899] Modules linked in:
[ 2187.044000] CPU: 0 PID: 11913 Comm: kworker/0:1 Not tainted 3.16.0-rc6+ #1151
[ 2187.044287] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2007
[ 2187.044287] Workqueue: nfsiod free_lock_state_work
[ 2187.044287] task: ffff880072b50cd0 ti: ffff88007a4ec000 task.ti: ffff88007a4ec000
[ 2187.044287] RIP: 0010:[<ffffffff81361ca6>]  [<ffffffff81361ca6>] free_lock_state_work+0x16/0x30
[ 2187.044287] RSP: 0018:ffff88007a4efd58  EFLAGS: 00010296
[ 2187.044287] RAX: 6b6b6b6b6b6b6b6b RBX: ffff88007a947ac0 RCX: 8000000000000000
[ 2187.044287] RDX: ffffffff826af9e0 RSI: ffff88007b093c00 RDI: ffff88007b093db8
[ 2187.044287] RBP: ffff88007a4efd58 R08: ffffffff832d3e10 R09: 000001c40efc0000
[ 2187.044287] R10: 0000000000000000 R11: 0000000000059e30 R12: ffff88007fc13240
[ 2187.044287] R13: ffff88007fc18b00 R14: ffff88007b093db8 R15: 0000000000000000
[ 2187.044287] FS:  0000000000000000(0000) GS:ffff88007fc00000(0000) knlGS:0000000000000000
[ 2187.044287] CS:  0010 DS: 0000 ES: 0000 CR0: 000000008005003b
[ 2187.044287] CR2: 00007f93ec33fb80 CR3: 0000000079dc2000 CR4: 00000000000006f0
[ 2187.044287] Stack:
[ 2187.044287]  ffff88007a4efdd8 ffffffff810cc877 ffffffff810cc80d ffff88007fc13258
[ 2187.044287]  000000007a947af0 0000000000000000 ffffffff8353ccc8 ffffffff82b6f3d0
[ 2187.044287]  0000000000000000 ffffffff82267679 ffff88007a4efdd8 ffff88007fc13240
[ 2187.044287] Call Trace:
[ 2187.044287]  [<ffffffff810cc877>] process_one_work+0x1c7/0x490
[ 2187.044287]  [<ffffffff810cc80d>] ? process_one_work+0x15d/0x490
[ 2187.044287]  [<ffffffff810cd569>] worker_thread+0x119/0x4f0
[ 2187.044287]  [<ffffffff810fbbad>] ? trace_hardirqs_on+0xd/0x10
[ 2187.044287]  [<ffffffff810cd450>] ? init_pwq+0x190/0x190
[ 2187.044287]  [<ffffffff810d3c6f>] kthread+0xdf/0x100
[ 2187.044287]  [<ffffffff810d3b90>] ? __init_kthread_worker+0x70/0x70
[ 2187.044287]  [<ffffffff81d9873c>] ret_from_fork+0x7c/0xb0
[ 2187.044287]  [<ffffffff810d3b90>] ? __init_kthread_worker+0x70/0x70
[ 2187.044287] Code: 0f 1f 44 00 00 31 c0 5d c3 66 66 66 2e 0f 1f 84 00 00 00 00 00 55 48 8d b7 48 fe ff ff 48 8b 87 58 fe ff ff 48 89 e5 48 8b 40 30 <48> 8b 00 48 8b 10 48 89 c7 48 8b 92 90 03 00 00 ff 52 28 5d c3
[ 2187.044287] RIP  [<ffffffff81361ca6>] free_lock_state_work+0x16/0x30
[ 2187.044287]  RSP <ffff88007a4efd58>
[ 2187.103626] ---[ end trace 0f11326d28e5d8fa ]---

The original reason for this patch was because the fl_release_private
operation couldn't sleep. With commit ed9814d858 (locks: defer freeing
locks in locks_delete_lock until after i_lock has been dropped), this is
no longer a problem so we can revert this patch.

Reported-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Tested-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2014-09-08 17:00:32 -07:00
Linus Torvalds 06b8ab5528 NFS client updates for Linux 3.17
Highlights include:
 
 - Stable fix for a bug in nfs3_list_one_acl()
 - Speed up NFS path walks by supporting LOOKUP_RCU
 - More read/write code cleanups
 - pNFS fixes for layout return on close
 - Fixes for the RCU handling in the rpcsec_gss code
 - More NFS/RDMA fixes
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Merge tag 'nfs-for-3.17-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs

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

   - stable fix for a bug in nfs3_list_one_acl()
   - speed up NFS path walks by supporting LOOKUP_RCU
   - more read/write code cleanups
   - pNFS fixes for layout return on close
   - fixes for the RCU handling in the rpcsec_gss code
   - more NFS/RDMA fixes"

* tag 'nfs-for-3.17-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs: (79 commits)
  nfs: reject changes to resvport and sharecache during remount
  NFS: Avoid infinite loop when RELEASE_LOCKOWNER getting expired error
  SUNRPC: remove all refcounting of groupinfo from rpcauth_lookupcred
  NFS: fix two problems in lookup_revalidate in RCU-walk
  NFS: allow lockless access to access_cache
  NFS: teach nfs_lookup_verify_inode to handle LOOKUP_RCU
  NFS: teach nfs_neg_need_reval to understand LOOKUP_RCU
  NFS: support RCU_WALK in nfs_permission()
  sunrpc/auth: allow lockless (rcu) lookup of credential cache.
  NFS: prepare for RCU-walk support but pushing tests later in code.
  NFS: nfs4_lookup_revalidate: only evaluate parent if it will be used.
  NFS: add checks for returned value of try_module_get()
  nfs: clear_request_commit while holding i_lock
  pnfs: add pnfs_put_lseg_async
  pnfs: find swapped pages on pnfs commit lists too
  nfs: fix comment and add warn_on for PG_INODE_REF
  nfs: check wait_on_bit_lock err in page_group_lock
  sunrpc: remove "ec" argument from encrypt_v2 operation
  sunrpc: clean up sparse endianness warnings in gss_krb5_wrap.c
  sunrpc: clean up sparse endianness warnings in gss_krb5_seal.c
  ...
2014-08-13 18:13:19 -06:00
NeilBrown 743162013d sched: Remove proliferation of wait_on_bit() action functions
The current "wait_on_bit" interface requires an 'action'
function to be provided which does the actual waiting.
There are over 20 such functions, many of them identical.
Most cases can be satisfied by one of just two functions, one
which uses io_schedule() and one which just uses schedule().

So:
 Rename wait_on_bit and        wait_on_bit_lock to
        wait_on_bit_action and wait_on_bit_lock_action
 to make it explicit that they need an action function.

 Introduce new wait_on_bit{,_lock} and wait_on_bit{,_lock}_io
 which are *not* given an action function but implicitly use
 a standard one.
 The decision to error-out if a signal is pending is now made
 based on the 'mode' argument rather than being encoded in the action
 function.

 All instances of the old wait_on_bit and wait_on_bit_lock which
 can use the new version have been changed accordingly and their
 action functions have been discarded.
 wait_on_bit{_lock} does not return any specific error code in the
 event of a signal so the caller must check for non-zero and
 interpolate their own error code as appropriate.

The wait_on_bit() call in __fscache_wait_on_invalidate() was
ambiguous as it specified TASK_UNINTERRUPTIBLE but used
fscache_wait_bit_interruptible as an action function.
David Howells confirms this should be uniformly
"uninterruptible"

The main remaining user of wait_on_bit{,_lock}_action is NFS
which needs to use a freezer-aware schedule() call.

A comment in fs/gfs2/glock.c notes that having multiple 'action'
functions is useful as they display differently in the 'wchan'
field of 'ps'. (and /proc/$PID/wchan).
As the new bit_wait{,_io} functions are tagged "__sched", they
will not show up at all, but something higher in the stack.  So
the distinction will still be visible, only with different
function names (gds2_glock_wait versus gfs2_glock_dq_wait in the
gfs2/glock.c case).

Since first version of this patch (against 3.15) two new action
functions appeared, on in NFS and one in CIFS.  CIFS also now
uses an action function that makes the same freezer aware
schedule call as NFS.

Signed-off-by: NeilBrown <neilb@suse.de>
Acked-by: David Howells <dhowells@redhat.com> (fscache, keys)
Acked-by: Steven Whitehouse <swhiteho@redhat.com> (gfs2)
Acked-by: Peter Zijlstra <peterz@infradead.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Steve French <sfrench@samba.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/20140707051603.28027.72349.stgit@notabene.brown
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-07-16 15:10:39 +02:00
Jeff Layton 49a4bda22e nfs4: queue free_lock_state job submission to nfsiod
We got a report of the following warning in Fedora:

BUG: sleeping function called from invalid context at mm/slub.c:969
in_atomic(): 1, irqs_disabled(): 0, pid: 533, name: bash
3 locks held by bash/533:
 #0:  (&sp->so_delegreturn_mutex){+.+...}, at: [<ffffffffa033da62>] nfs4_proc_lock+0x262/0x910 [nfsv4]
 #1:  (&nfsi->rwsem){.+.+.+}, at: [<ffffffffa033da6a>] nfs4_proc_lock+0x26a/0x910 [nfsv4]
 #2:  (&sb->s_type->i_lock_key#23){+.+...}, at: [<ffffffff812998dc>] flock_lock_file_wait+0x8c/0x3a0
CPU: 0 PID: 533 Comm: bash Not tainted 3.15.0-0.rc1.git1.1.fc21.x86_64 #1
Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
 0000000000000000 00000000d664ff3c ffff880078b69a70 ffffffff817e82e0
 0000000000000000 ffff880078b69a98 ffffffff810cf1a4 0000000000000050
 0000000000000050 ffff88007cc01a00 ffff880078b69ad8 ffffffff8121449e
Call Trace:
 [<ffffffff817e82e0>] dump_stack+0x4d/0x66
 [<ffffffff810cf1a4>] __might_sleep+0x184/0x240
 [<ffffffff8121449e>] kmem_cache_alloc_trace+0x4e/0x330
 [<ffffffffa0331124>] ? nfs4_release_lockowner+0x74/0x110 [nfsv4]
 [<ffffffffa0331124>] nfs4_release_lockowner+0x74/0x110 [nfsv4]
 [<ffffffffa0352340>] nfs4_put_lock_state+0x90/0xb0 [nfsv4]
 [<ffffffffa0352375>] nfs4_fl_release_lock+0x15/0x20 [nfsv4]
 [<ffffffff81297515>] locks_free_lock+0x45/0x90
 [<ffffffff8129996c>] flock_lock_file_wait+0x11c/0x3a0
 [<ffffffffa033da6a>] ? nfs4_proc_lock+0x26a/0x910 [nfsv4]
 [<ffffffffa033301e>] do_vfs_lock+0x1e/0x30 [nfsv4]
 [<ffffffffa033da79>] nfs4_proc_lock+0x279/0x910 [nfsv4]
 [<ffffffff810dbb26>] ? local_clock+0x16/0x30
 [<ffffffff810f5a3f>] ? lock_release_holdtime.part.28+0xf/0x200
 [<ffffffffa02f820c>] do_unlk+0x8c/0xc0 [nfs]
 [<ffffffffa02f85c5>] nfs_flock+0xa5/0xf0 [nfs]
 [<ffffffff8129a6f6>] locks_remove_file+0xb6/0x1e0
 [<ffffffff812159d8>] ? kfree+0xd8/0x2d0
 [<ffffffff8123bc63>] __fput+0xd3/0x210
 [<ffffffff8123bdee>] ____fput+0xe/0x10
 [<ffffffff810bfb6d>] task_work_run+0xcd/0xf0
 [<ffffffff81019cd1>] do_notify_resume+0x61/0x90
 [<ffffffff817fbea2>] int_signal+0x12/0x17

The problem is that NFSv4 is trying to do an allocation from
fl_release_private (in order to send a RELEASE_LOCKOWNER call). That
function can be called while holding the inode->i_lock, and it's
currently set up to do __GFP_WAIT allocations. v4.1 code has a
similar problem.

This patch adds a work_struct to the nfs4_lock_state and has the code
queue the free_lock_state operation to nfsiod.

Reported-by: Josh Stone <jistone@redhat.com>
Signed-off-by: Jeff Layton <jlayton@poochiereds.net>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2014-07-12 18:36:35 -04:00
Jeff Layton 8003d3c4aa nfs4: treat lock owners as opaque values
Do the following set of ops with a file on a NFSv4 mount:

    exec 3>>/file/on/nfsv4
    flock -x 3
    exec 3>&-

You'll see the LOCK request go across the wire, but no LOCKU when the
file is closed.

What happens is that the fd is passed across a fork, and the final close
is done in a different process than the opener. That makes
__nfs4_find_lock_state miss finding the correct lock state because it
uses the fl_pid as a search key. A new one is created, and the locking
code treats it as a delegation stateid (because NFS_LOCK_INITIALIZED
isn't set).

The root cause of this breakage seems to be commit 77041ed9b4
(NFSv4: Ensure the lockowners are labelled using the fl_owner and/or
fl_pid).

That changed it so that flock lockowners are allocated based on the
fl_pid. I think this is incorrect. flock locks should be "owned" by the
struct file, and that is already accounted for in the fl_owner field of
the lock request when it comes through nfs_flock.

This patch basically reverts the above commit and with it, a LOCKU is
sent in the above reproducer.

Signed-off-by: Jeff Layton <jlayton@poochiereds.net>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2014-07-12 18:36:31 -04:00
Linus Torvalds d1e1cda862 NFS client updates for Linux 3.16
Highlights include:
 
 - Massive cleanup of the NFS read/write code by Anna and Dros
 - Support multiple NFS read/write requests per page in order to deal with
   non-page aligned pNFS striping. Also cleans up the r/wsize < page size
   code nicely.
 - stable fix for ensuring inode is declared uptodate only after all the
   attributes have been checked.
 - stable fix for a kernel Oops when remounting
 - NFS over RDMA client fixes
 - move the pNFS files layout driver into its own subdirectory
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Merge tag 'nfs-for-3.16-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs

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

   - massive cleanup of the NFS read/write code by Anna and Dros
   - support multiple NFS read/write requests per page in order to deal
     with non-page aligned pNFS striping.  Also cleans up the r/wsize <
     page size code nicely.
   - stable fix for ensuring inode is declared uptodate only after all
     the attributes have been checked.
   - stable fix for a kernel Oops when remounting
   - NFS over RDMA client fixes
   - move the pNFS files layout driver into its own subdirectory"

* tag 'nfs-for-3.16-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs: (79 commits)
  NFS: populate ->net in mount data when remounting
  pnfs: fix lockup caused by pnfs_generic_pg_test
  NFSv4.1: Fix typo in dprintk
  NFSv4.1: Comment is now wrong and redundant to code
  NFS: Use raw_write_seqcount_begin/end int nfs4_reclaim_open_state
  xprtrdma: Disconnect on registration failure
  xprtrdma: Remove BUG_ON() call sites
  xprtrdma: Avoid deadlock when credit window is reset
  SUNRPC: Move congestion window constants to header file
  xprtrdma: Reset connection timeout after successful reconnect
  xprtrdma: Use macros for reconnection timeout constants
  xprtrdma: Allocate missing pagelist
  xprtrdma: Remove Tavor MTU setting
  xprtrdma: Ensure ia->ri_id->qp is not NULL when reconnecting
  xprtrdma: Reduce the number of hardway buffer allocations
  xprtrdma: Limit work done by completion handler
  xprtrmda: Reduce calls to ib_poll_cq() in completion handlers
  xprtrmda: Reduce lock contention in completion handlers
  xprtrdma: Split the completion queue
  xprtrdma: Make rpcrdma_ep_destroy() return void
  ...
2014-06-10 15:02:42 -07:00
Trond Myklebust abbec2da13 NFS: Use raw_write_seqcount_begin/end int nfs4_reclaim_open_state
The addition of lockdep code to write_seqcount_begin/end has lead to
a bunch of false positive claims of ABBA deadlocks with the so_lock
spinlock. Audits show that this simply cannot happen because the
read side code does not spin while holding so_lock.

Cc: <stable@vger.kernel.org> # 3.13.x
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2014-06-05 13:02:47 -04:00
Peter Zijlstra 4e857c58ef arch: Mass conversion of smp_mb__*()
Mostly scripted conversion of the smp_mb__* barriers.

Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Link: http://lkml.kernel.org/n/tip-55dhyhocezdw1dg7u19hmh1u@git.kernel.org
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: linux-arch@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-04-18 14:20:48 +02:00
Trond Myklebust 150e7260f3 NFSv4: Ensure we respect soft mount timeouts during trunking discovery
Tested-by: Steve Dickson <steved@redhat.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2014-03-19 08:34:40 -04:00
Trond Myklebust bd0f725c4c Merge branch 'devel' into linux-next 2014-03-17 15:15:21 -04:00
Trond Myklebust 927864cd92 NFSv4: Fix the return value of nfs4_select_rw_stateid
In commit 5521abfdcf (NFSv4: Resend the READ/WRITE RPC call
if a stateid change causes an error), we overloaded the return value of
nfs4_select_rw_stateid() to cause it to return -EWOULDBLOCK if an RPC
call is outstanding that would cause the NFSv4 lock or open stateid
to change.
That is all redundant when we actually copy the stateid used in the
read/write RPC call that failed, and check that against the current
stateid. It is doubly so, when we consider that in the NFSv4.1 case,
we also set the stateid's seqid to the special value '0', which means
'match the current valid stateid'.

Reported-by: Andy Adamson <andros@netapp.com>
Link: http://lkml.kernel.org/r/1393954269-3974-1-git-send-email-andros@netapp.com
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2014-03-05 11:55:24 -05:00
Trond Myklebust 4f14c194a9 NFSv4: Clear the open state flags if the new stateid does not match
RFC3530 and RFC5661 both prescribe that the 'opaque' field of the
open stateid returned by new OPEN/OPEN_DOWNGRADE/CLOSE calls for
the same file and open owner should match.
If this is not the case, assume that the open state has been lost,
and that we need to recover it.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2014-02-19 21:21:07 -05:00
Andy Adamson 146d70caaa NFS fix error return in nfs4_select_rw_stateid
Do not return an error when nfs4_copy_delegation_stateid succeeds.

Signed-off-by: Andy Adamson <andros@netapp.com>
Link: http://lkml.kernel.org/r/1392737765-41942-1-git-send-email-andros@netapp.com
Fixes: ef1820f9be (NFSv4: Don't try to recover NFSv4 locks when...)
Cc: NeilBrown <neilb@suse.de>
Cc: stable@vger.kernel.org # 3.12+
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2014-02-19 09:31:56 -05:00
Toralf Förster 16a6ddc709 point to the right include file in a comment (left over from a9004abc3)
Signed-off-by: Toralf Förster <toralf.foerster@gmx.de>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2014-01-05 15:51:35 -05:00
Linus Torvalds 673fdfe3f0 NFS client bugfixes:
- Stable fix for data corruption when retransmitting O_DIRECT writes
 - Stable fix for a deep recursion/stack overflow bug in rpc_release_client
 - Stable fix for infinite looping when mounting a NFSv4.x volume
 - Fix a typo in the nfs mount option parser
 - Allow pNFS layouts to be compiled into the kernel when NFSv4.1 is
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Merge tag 'nfs-for-3.13-2' of git://git.linux-nfs.org/projects/trondmy/linux-nfs

Pull NFS client bugfixes:
 - Stable fix for data corruption when retransmitting O_DIRECT writes
 - Stable fix for a deep recursion/stack overflow bug in rpc_release_client
 - Stable fix for infinite looping when mounting a NFSv4.x volume
 - Fix a typo in the nfs mount option parser
 - Allow pNFS layouts to be compiled into the kernel when NFSv4.1 is

* tag 'nfs-for-3.13-2' of git://git.linux-nfs.org/projects/trondmy/linux-nfs:
  nfs: fix pnfs Kconfig defaults
  NFS: correctly report misuse of "migration" mount option.
  nfs: don't retry detect_trunking with RPC_AUTH_UNIX more than once
  SUNRPC: Avoid deep recursion in rpc_release_client
  SUNRPC: Fix a data corruption issue when retransmitting RPC calls
2013-11-16 13:14:56 -08:00
Wolfram Sang 16735d022f tree-wide: use reinit_completion instead of INIT_COMPLETION
Use this new function to make code more comprehensible, since we are
reinitialzing the completion, not initializing.

[akpm@linux-foundation.org: linux-next resyncs]
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Acked-by: Linus Walleij <linus.walleij@linaro.org> (personally at LCE13)
Cc: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-11-15 09:32:21 +09:00
Jeff Layton 6d769f1e14 nfs: don't retry detect_trunking with RPC_AUTH_UNIX more than once
Currently, when we try to mount and get back NFS4ERR_CLID_IN_USE or
NFS4ERR_WRONGSEC, we create a new rpc_clnt and then try the call again.
There is no guarantee that doing so will work however, so we can end up
retrying the call in an infinite loop.

Worse yet, we create the new client using rpc_clone_client_set_auth,
which creates the new client as a child of the old one. Thus, we can end
up with a *very* long lineage of rpc_clnts. When we go to put all of the
references to them, we can end up with a long call chain that can smash
the stack as each rpc_free_client() call can recurse back into itself.

This patch fixes this by simply ensuring that the SETCLIENTID call will
only be retried in this situation if the last attempt did not use
RPC_AUTH_UNIX.

Note too that with this change, we don't need the (i > 2) check in the
-EACCES case since we now have a more reliable test as to whether we
should reattempt.

Cc: stable@vger.kernel.org # v3.10+
Cc: Chuck Lever <chuck.lever@oracle.com>
Tested-by/Acked-by: Weston Andros Adamson <dros@netapp.com>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2013-11-13 19:21:05 -05:00
Jeff Layton 1acd1c301f nfs: fix inverted test for delegation in nfs4_reclaim_open_state
commit 6686390bab (NFS: remove incorrect "Lock reclaim failed!"
warning.) added a test for a delegation before checking to see if any
reclaimed locks failed. The test however is backward and is only doing
that check when a delegation is held instead of when one isn't.

Cc: NeilBrown <neilb@suse.de>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Fixes: 6686390bab6a: NFS: remove incorrect "Lock reclaim failed!" warning.
Cc: stable@vger.kernel.org # 3.12
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2013-10-31 13:24:07 -04:00
Chuck Lever 0625c2dd6a NFS: Fix possible endless state recovery wait
In nfs4_wait_clnt_recover(), hold a reference to the clp being
waited on.  The state manager can reduce clp->cl_count to 1, in
which case the nfs_put_client() in nfs4_run_state_manager() can
free *clp before wait_on_bit() returns and allows
nfs4_wait_clnt_recover() to run again.

The behavior at that point is non-deterministic.  If the waited-on
bit still happens to be zero, wait_on_bit() will wake the waiter as
expected.  If the bit is set again (say, if the memory was poisoned
when freed) wait_on_bit() can leave the waiter asleep.

This is a narrow fix which ensures the safety of accessing *clp in
nfs4_wait_clnt_recover(), but does not address the continued use
of a possibly freed *clp after nfs4_wait_clnt_recover() returns
(see nfs_end_delegation_return(), for example).

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2013-10-28 15:31:55 -04:00
Chuck Lever d1c2331e75 NFS: Handle SEQ4_STATUS_LEASE_MOVED
With the advent of NFSv4 sessions in NFSv4.1 and following, a "lease
moved" condition is reported differently than it is in NFSv4.0.

NFSv4 minor version 0 servers return an error status code,
NFS4ERR_LEASE_MOVED, to signal that a lease has moved.  This error
causes the whole compound operation to fail.  Normal compounds
against this server continue to fail until the client performs
migration recovery on the migrated share.

Minor version 1 and later servers assert a bit flag in the reply to
a compound's SEQUENCE operation to signal LEASE_MOVED.  This is not
a fatal condition: operations against this server continue normally.
The server asserts this flag until the client performs migration
recovery on the migrated share.

Note that servers MUST NOT return NFS4ERR_LEASE_MOVED to NFSv4
clients not using NFSv4.0.

After the server asserts any of the sr_status_flags in the SEQUENCE
operation in a typical compound, our client initiates standard lease
recovery.  For NFSv4.1+, a stand-alone SEQUENCE operation is
performed to discover what recovery is needed.

If SEQ4_STATUS_LEASE_MOVED is asserted in this stand-alone SEQUENCE
operation, our client attempts to discover which FSIDs have been
migrated, and then performs migration recovery on each.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2013-10-28 15:31:07 -04:00
Chuck Lever b7f7a66e42 NFS: Support NFS4ERR_LEASE_MOVED recovery in state manager
A migration on the FSID in play for the current NFS operation
is reported via the error status code NFS4ERR_MOVED.

"Lease moved" means that a migration has occurred on some other
FSID than the one for the current operation.  It's a signal that
the client should take action immediately to handle a migration
that it may not have noticed otherwise.  This is so that the
client's lease does not expire unnoticed on the destination server.

In NFSv4.0, a moved lease is reported with the NFS4ERR_LEASE_MOVED
error status code.

To recover from NFS4ERR_LEASE_MOVED, check each FSID for that server
to see if it is still present.  Invoke nfs4_try_migration() if the
FSID is no longer present on the server.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2013-10-28 15:30:21 -04:00
Chuck Lever c9fdeb280b NFS: Add basic migration support to state manager thread
Migration recovery and state recovery must be serialized, so handle
both in the state manager thread.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2013-10-28 15:24:40 -04:00
Andy Adamson 3660cd4322 NFSv4 Remove zeroing state kern warnings
As of commit 5d422301f9 we no longer zero the
state.

Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2013-10-28 14:28:53 -04:00
NeilBrown ef1820f9be NFSv4: Don't try to recover NFSv4 locks when they are lost.
When an NFSv4 client loses contact with the server it can lose any
locks that it holds.

Currently when it reconnects to the server it simply tries to reclaim
those locks.  This might succeed even though some other client has
held and released a lock in the mean time.  So the first client might
think the file is unchanged, but it isn't.  This isn't good.

If, when recovery happens, the locks cannot be claimed because some
other client still holds the lock, then we get a message in the kernel
logs, but the client can still write.  So two clients can both think
they have a lock and can both write at the same time.  This is equally
not good.

There was a patch a while ago
  http://comments.gmane.org/gmane.linux.nfs/41917

which tried to address some of this, but it didn't seem to go
anywhere.  That patch would also send a signal to the process.  That
might be useful but for now this patch just causes writes to fail.

For NFSv4 (unlike v2/v3) there is a strong link between the lock and
the write request so we can fairly easily fail any IO of the lock is
gone.  While some applications might not expect this, it is still
safer than allowing the write to succeed.

Because this is a fairly big change in behaviour a module parameter,
"recover_locks", is introduced which defaults to true (the current
behaviour) but can be set to "false" to tell the client not to try to
recover things that were lost.

Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2013-09-04 12:26:32 -04:00
Chuck Lever b6a85258d8 NFS: Fix warning introduced by NFSv4.0 transport blocking patches
When CONFIG_NFS_V4_1 is not enabled, gcc emits this warning:

linux/fs/nfs/nfs4state.c:255:12: warning:
 ‘nfs4_begin_drain_session’ defined but not used [-Wunused-function]
 static int nfs4_begin_drain_session(struct nfs_client *clp)
            ^

Eventually NFSv4.0 migration recovery will invoke this function, but
that has not yet been merged.  Hide nfs4_begin_drain_session()
behind CONFIG_NFS_V4_1 for now.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2013-09-04 12:26:30 -04:00
Chuck Lever 2cf8bca8b9 NFS: Update session draining barriers for NFSv4.0 transport blocking
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2013-09-03 15:26:38 -04:00
Chuck Lever 9d33059c1b NFS: Enable slot table helpers for NFSv4.0
I'd like to re-use NFSv4.1's slot table machinery for NFSv4.0
transport blocking.  Re-organize some of nfs4session.c so the slot
table code is built even when NFS_V4_1 is disabled.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2013-09-03 15:26:33 -04:00