NFSv4.0 does not have TEST_STATEID/FREE_STATEID functionality, so
unlike NFSv4.1, the recovery procedure when stateids have expired or
have been revoked requires us to just forget the delegation.

http://lkml.kernel.org/r/CAN-5tyHwG=Cn2Q9KsHWadewjpTTy_K26ee+UnSvHvG4192p-Xw@mail.gmail.com
Cc: stable@vger.kernel.org
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

Somehow the nfs_v4_1_minor_ops had the NFS_CAP_SEEK flag set, enabling
SEEK over v4.1.  This is wrong, and can make servers crash.
Signed-off-by: NAnna Schumaker <Anna.Schumaker@Netapp.com>
Tested-by: NJ. Bruce Fields <bfields@redhat.com>
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

Variable 'err' needn't be initialized when nfs_getattr() uses it to
check whether it should call generic_fillattr() or not. That can result
in spurious error returns. Initialize 'err' properly.
Signed-off-by: NJan Kara <jack@suse.cz>
Cc: stable@vger.kernel.org
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

Commit 3a6fd1f0 (pnfs/blocklayout: remove read-modify-write handling
in bl_write_pagelist) introduced a bogus assignment pg_index = pg_index
in variable initialization. AFAICS it's just a typo so remove it.
Spotted by Coverity (id 1248711).

CC: Christoph Hellwig <hch@lst.de>
Signed-off-by: NJan Kara <jack@suse.cz>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

This WARN_ON_ONCE was supposed to catch reference counting bugs, but can
trigger in inappropriate situations.

This was reproducible using NFSv2 on an architecture with 64K pages -- we
verified that it was not a reference counting bug and the warning was
safe to ignore.
Reported-by: NWill Deacon <will.deacon@arm.com>
Tested-by: NWill Deacon <will.deacon@arm.com>
Signed-off-by: NWeston Andros Adamson <dros@primarydata.com>
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

The rpc_pipefs code isn't thread safe, leading to occasional use after
frees when running xfstests generic/241 (dbench).
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Link: http://lkml.kernel.org/r/1411740170-18611-2-git-send-email-hch@lst.de
Cc: stable@vger.kernel.org # 3.17.x
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

For pNFS direct writes, layout driver may dynamically allocate ds_cinfo.buckets.
So we need to take care to free them when freeing dreq.

Ideally this needs to be done inside layout driver where ds_cinfo.buckets
are allocated. But buckets are attached to dreq and reused across LD IO iterations.
So I feel it's OK to free them in the generic layer.

Cc: stable@vger.kernel.org [v3.4+]
Signed-off-by: NPeng Tao <tao.peng@primarydata.com>
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

This reverts commit 4fa2c54b.

This reverts commit f39c0104.

If the OPEN rpc call to the server fails with an ENOENT call, nfs_atomic_open
will create a negative dentry for that file, however it currently fails
to call nfs_set_verifier(), thus causing the dentry to be immediately
revalidated on the next call to nfs_lookup_revalidate() instead of following
the usual lookup caching rules.
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

I no longer have access to the Panasas email.
So change to an email that can always reach me.
Signed-off-by: NBoaz Harrosh <ooo@electrozaur.com>

REQ_KERNEL is no longer used. Remove it and drop the redundant uio
argument to nfs_file_direct_{read,write}.
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>
Cc: Christoph Hellwig <hch@infradead.org>
Reported-by: NDan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: NJens Axboe <axboe@fb.com>

It is OK for pageused == pagecount in the loop, as long as we don't add
another entry to the *pages array. Move the test so that it only triggers
in that case.
Reported-by: NSteve Dickson <SteveD@redhat.com>
Fixes: bba5c188 (nfs: disallow duplicate pages in pgio page vectors)
Cc: Weston Andros Adamson <dros@primarydata.com>
Cc: stable@vger.kernel.org # 3.16.x
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

SteveD reports the following Oops:
 RIP: 0010:[<ffffffffa053461d>]  [<ffffffffa053461d>] __put_nfs_open_context+0x1d/0x100 [nfs]
 RSP: 0018:ffff880fed687b90  EFLAGS: 00010286
 RAX: 0000000000000024 RBX: 0000000000000000 RCX: 0000000000000006
 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
 RBP: ffff880fed687bc0 R08: 0000000000000092 R09: 000000000000047a
 R10: 0000000000000000 R11: ffff880fed6878d6 R12: ffff880fed687d20
 R13: ffff880fed687d20 R14: 0000000000000070 R15: ffffea000aa33ec0
 FS:  00007fce290f0740(0000) GS:ffff8807ffc60000(0000) knlGS:0000000000000000
 CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
 CR2: 0000000000000070 CR3: 00000007f2e79000 CR4: 00000000000007e0
 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
 Stack:
  0000000000000000 ffff880036c5e510 ffff880fed687d20 ffff880fed687d20
  ffff880036c5e200 ffffea000aa33ec0 ffff880fed687bd0 ffffffffa0534710
  ffff880fed687be8 ffffffffa053d5f0 ffff880036c5e200 ffff880fed687c08
 Call Trace:
  [<ffffffffa0534710>] put_nfs_open_context+0x10/0x20 [nfs]
  [<ffffffffa053d5f0>] nfs_pgio_data_destroy+0x20/0x40 [nfs]
  [<ffffffffa053d672>] nfs_pgio_error+0x22/0x40 [nfs]
  [<ffffffffa053d8f4>] nfs_generic_pgio+0x74/0x2e0 [nfs]
  [<ffffffffa06b18c3>] pnfs_generic_pg_writepages+0x63/0x210 [nfsv4]
  [<ffffffffa053d579>] nfs_pageio_doio+0x19/0x50 [nfs]
  [<ffffffffa053eb84>] nfs_pageio_complete+0x24/0x30 [nfs]
  [<ffffffffa053cb25>] nfs_direct_write_schedule_iovec+0x115/0x1f0 [nfs]
  [<ffffffffa053675f>] ? nfs_get_lock_context+0x4f/0x120 [nfs]
  [<ffffffffa053d252>] nfs_file_direct_write+0x262/0x420 [nfs]
  [<ffffffffa0532d91>] nfs_file_write+0x131/0x1d0 [nfs]
  [<ffffffffa0532c60>] ? nfs_need_sync_write.isra.17+0x40/0x40 [nfs]
  [<ffffffff812127b8>] do_io_submit+0x3b8/0x840
  [<ffffffff81212c50>] SyS_io_submit+0x10/0x20
  [<ffffffff81610f29>] system_call_fastpath+0x16/0x1b

This is due to the calls to nfs_pgio_error() in nfs_generic_pgio(), which
happen before the nfs_pgio_header's open context is referenced in
nfs_pgio_rpcsetup().
Reported-by: NSteve Dickson <SteveD@redhat.com>
Cc: stable@vger.kernel.org # 3.16.x
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

Now that d_invalidate can no longer fail, stop returning a useless
return code.  For the few callers that checked the return code update
remove the handling of d_invalidate failure.
Reviewed-by: NMiklos Szeredi <miklos@szeredi.hu>
Signed-off-by: N"Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Now that check_submounts_and_drop can not fail and is called from
d_invalidate there is no longer a need to call check_submounts_and_drom
from filesystem d_revalidate methods so remove it.
Reviewed-by: NMiklos Szeredi <miklos@szeredi.hu>
Signed-off-by: N"Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

You cannot call pnfs_put_lseg_async() more than once per lseg, so it
is really an inappropriate way to deal with a refcount issue.

Instead, replace it with a function that decrements the refcount, and
puts the final 'free' operation (which is incompatible with locks) on
the workqueue.

Cc: Weston Andros Adamson <dros@primarydata.com>
Fixes: e6cf82d1: pnfs: add pnfs_put_lseg_async
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

nfs4_insert_deviceid_node() was removed in 661373b1Signed-off-by: NTom Haynes <loghyr@primarydata.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

Commit 2f60ea6b ("NFSv4: The NFSv4.0 client must send RENEW calls if it holds a delegation") set the NFS4_RENEW_TIMEOUT flag in nfs4_renew_state, and does
not put an nfs41_proc_async_sequence call, the NFSv4.1 lease renewal heartbeat
call, on the wire to renew the NFSv4.1 state if the flag was not set.

The NFS4_RENEW_TIMEOUT flag is set when "now" is after the last renewal
(cl_last_renewal) plus the lease time divided by 3. This is arbitrary and
sometimes does the following:

In normal operation, the only way a future state renewal call is put on the
wire is via a call to nfs4_schedule_state_renewal, which schedules a
nfs4_renew_state workqueue task. nfs4_renew_state determines if the
NFS4_RENEW_TIMEOUT should be set, and the calls nfs41_proc_async_sequence,
which only gets sent if the NFS4_RENEW_TIMEOUT flag is set.
Then the nfs41_proc_async_sequence rpc_release function schedules
another state remewal via nfs4_schedule_state_renewal.

Without this change we can get into a state where an application stops
accessing the NFSv4.1 share, state renewal calls stop due to the
NFS4_RENEW_TIMEOUT flag _not_ being set. The only way to recover
from this situation is with a clientid re-establishment, once the application
resumes and the server has timed out the lease and so returns
NFS4ERR_BAD_SESSION on the subsequent SEQUENCE operation.

An example application:
open, lock, write a file.

sleep for 6 * lease (could be less)

ulock, close.

In the above example with NFSv4.1 delegations enabled, without this change,
there are no OP_SEQUENCE state renewal calls during the sleep, and the
clientid is recovered due to lease expiration on the close.

This issue does not occur with NFSv4.1 delegations disabled, nor with
NFSv4.0, with or without delegations enabled.
Signed-off-by: NAndy Adamson <andros@netapp.com>
Link: http://lkml.kernel.org/r/1411486536-23401-1-git-send-email-andros@netapp.com
Fixes: 2f60ea6b (NFSv4: The NFSv4.0 client must send RENEW calls...)
Cc: stable@vger.kernel.org # 3.2.x
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

The SEEK operation is used when an application makes an lseek call with
either the SEEK_HOLE or SEEK_DATA flags set.  I fall back on
nfs_file_llseek() if the server does not have SEEK support.
Signed-off-by: NAnna Schumaker <Anna.Schumaker@Netapp.com>
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

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: NTrond Myklebust <trond.myklebust@primarydata.com>

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: NTrond Myklebust <trond.myklebust@primarydata.com>

When fabricating a server index key for fscache, we should clear the index key
buffer before starting to fill it in, not in the middle.
Reported-by: NJames Pearson <james-p@moving-picture.com>
Signed-off-by: NDavid Howells <dhowells@redhat.com>
Acked-by: NSteve Dickson <steved@redhat.com>
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

Silence a few warnings about missing symbols that are due to missing
includes of nfs3_fs.h.

Fixes: 00a36a10 (NFS: Move v3 declarations out of internal.h)
Fixes: cb8c20fa (NFS: Move NFS v3 acl functions to nfs3_fs.h)
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

Now that nfs_release_page() doesn't block indefinitely, other deadlock
avoidance mechanisms aren't needed.
 - it doesn't hurt for kswapd to block occasionally.  If it doesn't
   want to block it would clear __GFP_WAIT.  The current_is_kswapd()
   was only added to avoid deadlocks and we have a new approach for
   that.
 - memory allocation in the SUNRPC layer can very rarely try to
   ->releasepage() a page it is trying to handle.  The deadlock
   is removed as nfs_release_page() doesn't block indefinitely.

So we don't need to set PF_FSTRANS for sunrpc network operations any
more.
Signed-off-by: NNeilBrown <neilb@suse.de>
Acked-by: NJeff Layton <jlayton@primarydata.com>
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

If nfs_release_page() is called on a sequence of pages which are all
in the same file which is blocked on COMMIT, each page could
contribute a 1 second delay which could be come excessive.  I have
seen delays of as much as 208 seconds.

To keep the delay to one second, mark the bdi as write-congested
if the commit didn't finished.  Once it does finish, the
write-congested flag will be cleared by nfs_commit_release_pages().

With this, the longest total delay in try_to_free_pages that I have
seen is under 3 seconds.  With no waiting in nfs_release_page at all
I have seen delays of nearly 1.5 seconds.
Signed-off-by: NNeilBrown <neilb@suse.de>
Acked-by: NJeff Layton <jlayton@primarydata.com>
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

Support for loop-back mounted NFS filesystems is useful when NFS is
used to access shared storage in a high-availability cluster.

If the node running the NFS server fails, some other node can mount the
filesystem and start providing NFS service.  If that node already had
the filesystem NFS mounted, it will now have it loop-back mounted.

nfsd can suffer a deadlock when allocating memory and entering direct
reclaim.
While direct reclaim does not write to the NFS filesystem it can send
and wait for a COMMIT through nfs_release_page().

This patch modifies nfs_release_page() to wait a limited time for the
commit to complete - one second.  If the commit doesn't complete
in this time, nfs_release_page() will fail.  This means it might now
fail in some cases where it wouldn't before.  These cases are only
when 'gfp' includes '__GFP_WAIT'.

nfs_release_page() is only called by try_to_release_page(), and that
can only be called on an NFS page with required 'gfp' flags from
 - page_cache_pipe_buf_steal() in splice.c
 - shrink_page_list() in vmscan.c
 - invalidate_inode_pages2_range() in truncate.c

The first two handle failure quite safely.  The last is only called
after ->launder_page() has been called, and that will have waited
for the commit to finish already.

So aborting if the commit takes longer than 1 second is perfectly safe.
Signed-off-by: NNeilBrown <neilb@suse.de>
Acked-by: NJeff Layton <jlayton@primarydata.com>
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

commit b31268ac
  FS: Use stable writes when not doing a bulk flush

was a bit heavy handed.
The particular problem that lead to this patch was that
small writes to an O_SYNC file we being written as UNSTABLE writes
followed by a commit.
This is appropriate for large writes (which require multiple NFS
requests) but for small writes (single NFS request), using
NFS_FILE_SYNC is more efficient.

So that patch causes the code to select between the two methods
depending on how many nfs requests get generated.

Unfortunately this ends up applying to non O_SYNC writes as well.
In particular if you memory-map a file and update random pages, then
when they are eventually written out by writeback they will go as
NFS_FILE_SYNC.  This is inefficient and slows down the application.

So: only set FLUSH_COND_STABLE when wbc->sync_mode is WB_SYNC_ALL.
With this patch:
 O_SYNC writes are NFS_FILE_SYNC for single requests, and NFS_UNSTABLE
    followed by COMMIT for multiple requests
 Writing immediately before close of fsync follow the same pattern.
 Non-O_SYNC writes without an fsync of close eventually get flushed
 out as UNSTABLE and a commit follows eventually as appropriate.
Signed-off-by: NNeilBrown <neilb@suse.de>
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

Currently asynchronous NFSv4 request will be retried with
exponential timeout (from 1/10 to 15 seconds), but async
requests will always use a 15second retry.

Some "async" requests are really synchronous though.  The
async mechanism is used to allow the request to continue if
the requesting process is killed.
In those cases, an exponential retry is appropriate.

For example, if two different clients both open a file and
get a READ delegation, and one client then unlinks the file
(while still holding an open file descriptor), that unlink
will used the "silly-rename" handling which is async.
The first rename will result in NFS4ERR_DELAY while the
delegation is reclaimed from the other client.  The rename
will not be retried for 15 seconds, causing an unlink to take
15 seconds rather than 100msec.

This patch only added exponential timeout for async unlink and
async rename.  Other async calls, such as 'close' are sometimes
waited for so they might benefit from exponential timeout too.
Signed-off-by: NNeilBrown <neilb@suse.de>
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

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: NOlga Kornievskaia <kolga@netapp.com>
Fixes: c9fdeb28 (NFS: Add basic migration support to state manager thread)
Cc: stable@vger.kernel.org # 3.13+
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

Commit 65b38851
("NFS: Fix /proc/fs/nfsfs/servers and /proc/fs/nfsfs/volumes")

updated the following function:
static int nfs_volume_list_open(struct inode *inode, struct file *file)

it used &nfs_server_list_ops instead of &nfs_volume_list_ops
which means cat /proc/fs/nfsfs/volumes = /proc/fs/nfsfs/servers
Signed-off-by: NFabian Frederick <fabf@skynet.be>
Fixes: 65b38851 (NFS: Fix /proc/fs/nfsfs/servers and...)
Cc: stable@vger.kernel.org # 3.4.x+
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

kbuild test robot reports:

   fs/built-in.o: In function `bl_map_stripe':
   >> :(.text+0x965b4): undefined reference to `__aeabi_uldivmod'
   >> :(.text+0x965cc): undefined reference to `__aeabi_uldivmod'
   >> :(.text+0x96604): undefined reference to `__aeabi_uldivmod'

Fixes: 5c83746a (pnfs/blocklayout: in-kernel GETDEVICEINFO XDR parsing)
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Christoph Hellwig <hch@lst.de>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

schedule(), io_schedule() and schedule_timeout() always return
with TASK_RUNNING state set, so one more setting is unnecessary.

(All places in patch are visible good, only exception is
 kiblnd_scheduler() from:

      drivers/staging/lustre/lnet/klnds/o2iblnd/o2iblnd_cb.c

 Its schedule() is one line above standard 3 lines of unified diff)

No places where set_current_state() is used for mb().
Signed-off-by: NKirill Tkhai <ktkhai@parallels.com>
Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1410529254.3569.23.camel@tkhai
Cc: Alasdair Kergon <agk@redhat.com>
Cc: Anil Belur <askb23@gmail.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Dave Kleikamp <shaggy@kernel.org>
Cc: David Airlie <airlied@linux.ie>
Cc: David Howells <dhowells@redhat.com>
Cc: Dmitry Eremin <dmitry.eremin@intel.com>
Cc: Frank Blaschka <blaschka@linux.vnet.ibm.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Helge Deller <deller@gmx.de>
Cc: Isaac Huang <he.huang@intel.com>
Cc: James E.J. Bottomley <JBottomley@parallels.com>
Cc: James E.J. Bottomley <jejb@parisc-linux.org>
Cc: J. Bruce Fields <bfields@fieldses.org>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: Jesper Nilsson <jesper.nilsson@axis.com>
Cc: Jiri Slaby <jslaby@suse.cz>
Cc: Laura Abbott <lauraa@codeaurora.org>
Cc: Liang Zhen <liang.zhen@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Masaru Nomura <massa.nomura@gmail.com>
Cc: Michael Opdenacker <michael.opdenacker@free-electrons.com>
Cc: Mikael Starvik <starvik@axis.com>
Cc: Mike Snitzer <snitzer@redhat.com>
Cc: Neil Brown <neilb@suse.de>
Cc: Oleg Drokin <green@linuxhacker.ru>
Cc: Peng Tao <bergwolf@gmail.com>
Cc: Richard Weinberger <richard@nod.at>
Cc: Robert Love <robert.w.love@intel.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Trond Myklebust <trond.myklebust@primarydata.com>
Cc: Ursula Braun <ursula.braun@de.ibm.com>
Cc: Zi Shen Lim <zlim.lnx@gmail.com>
Cc: devel@driverdev.osuosl.org
Cc: dm-devel@redhat.com
Cc: dri-devel@lists.freedesktop.org
Cc: fcoe-devel@open-fcoe.org
Cc: jfs-discussion@lists.sourceforge.net
Cc: linux390@de.ibm.com
Cc: linux-afs@lists.infradead.org
Cc: linux-cris-kernel@axis.com
Cc: linux-kernel@vger.kernel.org
Cc: linux-nfs@vger.kernel.org
Cc: linux-parisc@vger.kernel.org
Cc: linux-raid@vger.kernel.org
Cc: linux-s390@vger.kernel.org
Cc: linux-scsi@vger.kernel.org
Cc: qla2xxx-upstream@qlogic.com
Cc: user-mode-linux-devel@lists.sourceforge.net
Cc: user-mode-linux-user@lists.sourceforge.net
Signed-off-by: NIngo Molnar <mingo@kernel.org>

James Drew reports another bug whereby the NFS client is now sending
an OPEN_DOWNGRADE in a situation where it should really have sent a
CLOSE: the client is opening the file for O_RDWR, but then trying to
do a downgrade to O_RDONLY, which is not allowed by the NFSv4 spec.
Reported-by: NJames Drews <drews@engr.wisc.edu>
Link: http://lkml.kernel.org/r/541AD7E5.8020409@engr.wisc.edu
Fixes: aee7af35 (NFSv4: Fix problems with close in the presence...)
Cc: stable@vger.kernel.org # 2.6.33+
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

There is a race between nfs4_state_manager() and
nfs_server_remove_lists() that happens during a nfsv3 mount.

The v3 mount notices there is already a supper block so
nfs_server_remove_lists() called which uses the nfs_client_lock
spin lock to synchronize access to the client list.

At the same time nfs4_state_manager() is running through
the client list looking for work to do, using the same
lock. When nfs4_state_manager() wins the race to the
list, a v3 client pointer is found and not ignored
properly which causes the panic.

Moving some protocol checks before the state checking
avoids the panic.

CC: Stable Tree <stable@vger.kernel.org>
Signed-off-by: NSteve Dickson <steved@redhat.com>
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

A previous patch added a ->match_preparse() method to the key type.  This is
allowed to override the function called by the iteration algorithm.
Therefore, we can just set a default that simply checks for an exact match of
the key description with the original criterion data and allow match_preparse
to override it as needed.

The key_type::match op is then redundant and can be removed, as can the
user_match() function.
Signed-off-by: NDavid Howells <dhowells@redhat.com>
Acked-by: NVivek Goyal <vgoyal@redhat.com>

Signed-off-by: NStephen Rothwell <sfr@canb.auug.org.au>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

Both blocks layout and objects layout want to use it to avoid CB_LAYOUTRECALL
but that should only happen if client is doing truncation to a smaller size.
For other cases, we let server decide if it wants to recall client's layouts.
Change PNFS_LAYOUTRET_ON_SETATTR to follow the logic and not to send
layoutreturn unnecessarily.

Cc: Christoph Hellwig <hch@lst.de>
Cc: Boaz Harrosh <boaz@plexistor.com>
Signed-off-by: NPeng Tao <tao.peng@primarydata.com>
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

This code is internal to the v3 module, so other parts of the client
shouldn't have any knowledge of it.

nfs3_getxattr(), nfs3_setxattr(), and nfs3_removexattr() no longer exist
anywhere so I remove the declarations while I'm here.
Signed-off-by: NAnna Schumaker <Anna.Schumaker@Netapp.com>
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

This check is already performed by the module loading code - if the
module can't be found then -EPROTONOSUPPORT will be returned.  Let's
handle v3 this way, too.
Signed-off-by: NAnna Schumaker <Anna.Schumaker@Netapp.com>
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>