Commit Graph

494 Commits

Author SHA1 Message Date
Linus Torvalds efd52b5d36 NFS client updates for Linux 4.16
Highlights include:
 
 Stable bugfixes:
 - Fix breakages in the nfsstat utility due to the inclusion of the NFSv4
   LOOKUPP operation.
 - Fix a NULL pointer dereference in nfs_idmap_prepare_pipe_upcall() due to
   nfs_idmap_legacy_upcall() being called without an 'aux' parameter.
 - Fix a refcount leak in the standard O_DIRECT error path.
 - Fix a refcount leak in the pNFS O_DIRECT fallback to MDS path.
 - Fix CPU latency issues with nfs_commit_release_pages()
 - Fix the LAYOUTUNAVAILABLE error case in the file layout type.
 - NFS: Fix a race between mmap() and O_DIRECT
 
 Features:
 - Support the statx() mask and query flags to enable optimisations when
   the user is requesting only attributes that are already up to date in
   the inode cache, or is specifying the AT_STATX_DONT_SYNC flag.
 - Add a module alias for the SCSI pNFS layout type.
 
 Bugfixes:
 - Automounting when resolving a NFSv4 referral should preserve the RDMA
   transport protocol settings.
 - Various other RDMA bugfixes from Chuck.
 - pNFS block layout fixes.
 - Always set NFS_LOCK_LOST when a lock is lost.
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Merge tag 'nfs-for-4.16-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs

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

  Stable bugfixes:

   - Fix breakages in the nfsstat utility due to the inclusion of the
     NFSv4 LOOKUPP operation

   - Fix a NULL pointer dereference in nfs_idmap_prepare_pipe_upcall()
     due to nfs_idmap_legacy_upcall() being called without an 'aux'
     parameter

   - Fix a refcount leak in the standard O_DIRECT error path

   - Fix a refcount leak in the pNFS O_DIRECT fallback to MDS path

   - Fix CPU latency issues with nfs_commit_release_pages()

   - Fix the LAYOUTUNAVAILABLE error case in the file layout type

   - NFS: Fix a race between mmap() and O_DIRECT

  Features:

   - Support the statx() mask and query flags to enable optimisations
     when the user is requesting only attributes that are already up to
     date in the inode cache, or is specifying the AT_STATX_DONT_SYNC
     flag

   - Add a module alias for the SCSI pNFS layout type

  Bugfixes:

   - Automounting when resolving a NFSv4 referral should preserve the
     RDMA transport protocol settings

   - Various other RDMA bugfixes from Chuck

   - pNFS block layout fixes

   - Always set NFS_LOCK_LOST when a lock is lost"

* tag 'nfs-for-4.16-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs: (69 commits)
  NFS: Fix a race between mmap() and O_DIRECT
  NFS: Remove a redundant call to unmap_mapping_range()
  pnfs/blocklayout: Ensure disk address in block device map
  pnfs/blocklayout: pnfs_block_dev_map uses bytes, not sectors
  lockd: Fix server refcounting
  SUNRPC: Fix null rpc_clnt dereference in rpc_task_queued tracepoint
  SUNRPC: Micro-optimize __rpc_execute
  SUNRPC: task_run_action should display tk_callback
  sunrpc: Format RPC events consistently for display
  SUNRPC: Trace xprt_timer events
  xprtrdma: Correct some documenting comments
  xprtrdma: Fix "bytes registered" accounting
  xprtrdma: Instrument allocation/release of rpcrdma_req/rep objects
  xprtrdma: Add trace points to instrument QP and CQ access upcalls
  xprtrdma: Add trace points in the client-side backchannel code paths
  xprtrdma: Add trace points for connect events
  xprtrdma: Add trace points to instrument MR allocation and recovery
  xprtrdma: Add trace points to instrument memory invalidation
  xprtrdma: Add trace points in reply decoder path
  xprtrdma: Add trace points to instrument memory registration
  ..
2018-01-30 19:03:48 -08:00
Linus Torvalds a4b7fd7d34 inode->i_version rework for v4.16
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Merge tag 'iversion-v4.16-1' of git://git.kernel.org/pub/scm/linux/kernel/git/jlayton/linux

Pull inode->i_version rework from Jeff Layton:
 "This pile of patches is a rework of the inode->i_version field. We
  have traditionally incremented that field on every inode data or
  metadata change. Typically this increment needs to be logged on disk
  even when nothing else has changed, which is rather expensive.

  It turns out though that none of the consumers of that field actually
  require this behavior. The only real requirement for all of them is
  that it be different iff the inode has changed since the last time the
  field was checked.

  Given that, we can optimize away most of the i_version increments and
  avoid dirtying inode metadata when the only change is to the i_version
  and no one is querying it. Queries of the i_version field are rather
  rare, so we can help write performance under many common workloads.

  This patch series converts existing accesses of the i_version field to
  a new API, and then converts all of the in-kernel filesystems to use
  it. The last patch in the series then converts the backend
  implementation to a scheme that optimizes away a large portion of the
  metadata updates when no one is looking at it.

  In my own testing this series significantly helps performance with
  small I/O sizes. I also got this email for Christmas this year from
  the kernel test robot (a 244% r/w bandwidth improvement with XFS over
  DAX, with 4k writes):

    https://lkml.org/lkml/2017/12/25/8

  A few of the earlier patches in this pile are also flowing to you via
  other trees (mm, integrity, and nfsd trees in particular)".

* tag 'iversion-v4.16-1' of git://git.kernel.org/pub/scm/linux/kernel/git/jlayton/linux: (22 commits)
  fs: handle inode->i_version more efficiently
  btrfs: only dirty the inode in btrfs_update_time if something was changed
  xfs: avoid setting XFS_ILOG_CORE if i_version doesn't need incrementing
  fs: only set S_VERSION when updating times if necessary
  IMA: switch IMA over to new i_version API
  xfs: convert to new i_version API
  ufs: use new i_version API
  ocfs2: convert to new i_version API
  nfsd: convert to new i_version API
  nfs: convert to new i_version API
  ext4: convert to new i_version API
  ext2: convert to new i_version API
  exofs: switch to new i_version API
  btrfs: convert to new i_version API
  afs: convert to new i_version API
  affs: convert to new i_version API
  fat: convert to new i_version API
  fs: don't take the i_lock in inode_inc_iversion
  fs: new API for handling inode->i_version
  ntfs: remove i_version handling
  ...
2018-01-29 13:33:53 -08:00
Jeff Layton 1eb5d98f16 nfs: convert to new i_version API
For NFS, we just use the "raw" API since the i_version is mostly
managed by the server. The exception there is when the client
holds a write delegation, but we only need to bump it once
there anyway to handle CB_GETATTR.

Tested-by: Krzysztof Kozlowski <krzk@kernel.org>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
2018-01-29 06:42:21 -05:00
Trond Myklebust 7f1bda447c NFS: Add a cond_resched() to nfs_commit_release_pages()
The commit list can get very large, and so we need a cond_resched()
in nfs_commit_release_pages() in order to ensure we don't hog the CPU
for excessive periods of time.

Reported-by: Mike Galbraith <efault@gmx.de>
Cc: stable@vger.kernel.org
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2018-01-14 23:06:28 -05:00
Scott Mayhew dc4fd9ab01 nfs: don't wait on commit in nfs_commit_inode() if there were no commit requests
If there were no commit requests, then nfs_commit_inode() should not
wait on the commit or mark the inode dirty, otherwise the following
BUG_ON can be triggered:

[ 1917.130762] kernel BUG at fs/inode.c:578!
[ 1917.130766] Oops: Exception in kernel mode, sig: 5 [#1]
[ 1917.130768] SMP NR_CPUS=2048 NUMA pSeries
[ 1917.130772] Modules linked in: iscsi_tcp libiscsi_tcp libiscsi scsi_transport_iscsi blocklayoutdriver rpcsec_gss_krb5 auth_rpcgss nfsv4 dns_resolver nfs lockd grace fscache sunrpc sg nx_crypto pseries_rng ip_tables xfs libcrc32c sd_mod crc_t10dif crct10dif_generic crct10dif_common ibmvscsi scsi_transport_srp ibmveth scsi_tgt dm_mirror dm_region_hash dm_log dm_mod
[ 1917.130805] CPU: 2 PID: 14923 Comm: umount.nfs4 Tainted: G               ------------ T 3.10.0-768.el7.ppc64 #1
[ 1917.130810] task: c0000005ecd88040 ti: c00000004cea0000 task.ti: c00000004cea0000
[ 1917.130813] NIP: c000000000354178 LR: c000000000354160 CTR: c00000000012db80
[ 1917.130816] REGS: c00000004cea3720 TRAP: 0700   Tainted: G               ------------ T  (3.10.0-768.el7.ppc64)
[ 1917.130820] MSR: 8000000100029032 <SF,EE,ME,IR,DR,RI>  CR: 22002822  XER: 20000000
[ 1917.130828] CFAR: c00000000011f594 SOFTE: 1
GPR00: c000000000354160 c00000004cea39a0 c0000000014c4700 c0000000018cc750
GPR04: 000000000000c750 80c0000000000000 0600000000000000 04eeb76bea749a03
GPR08: 0000000000000034 c0000000018cc758 0000000000000001 d000000005e619e8
GPR12: c00000000012db80 c000000007b31200 0000000000000000 0000000000000000
GPR16: 0000000000000000 0000000000000000 0000000000000000 0000000000000000
GPR20: 0000000000000000 0000000000000000 0000000000000000 0000000000000000
GPR24: 0000000000000000 c000000000dfc3ec 0000000000000000 c0000005eefc02c0
GPR28: d0000000079dbd50 c0000005b94a02c0 c0000005b94a0250 c0000005b94a01c8
[ 1917.130867] NIP [c000000000354178] .evict+0x1c8/0x350
[ 1917.130871] LR [c000000000354160] .evict+0x1b0/0x350
[ 1917.130873] Call Trace:
[ 1917.130876] [c00000004cea39a0] [c000000000354160] .evict+0x1b0/0x350 (unreliable)
[ 1917.130880] [c00000004cea3a30] [c0000000003558cc] .evict_inodes+0x13c/0x270
[ 1917.130884] [c00000004cea3af0] [c000000000327d20] .kill_anon_super+0x70/0x1e0
[ 1917.130896] [c00000004cea3b80] [d000000005e43e30] .nfs_kill_super+0x20/0x60 [nfs]
[ 1917.130900] [c00000004cea3c00] [c000000000328a20] .deactivate_locked_super+0xa0/0x1b0
[ 1917.130903] [c00000004cea3c80] [c00000000035ba54] .cleanup_mnt+0xd4/0x180
[ 1917.130907] [c00000004cea3d10] [c000000000119034] .task_work_run+0x114/0x150
[ 1917.130912] [c00000004cea3db0] [c00000000001ba6c] .do_notify_resume+0xcc/0x100
[ 1917.130916] [c00000004cea3e30] [c00000000000a7b0] .ret_from_except_lite+0x5c/0x60
[ 1917.130919] Instruction dump:
[ 1917.130921] 7fc3f378 486734b5 60000000 387f00a0 38800003 4bdcb365 60000000 e95f00a0
[ 1917.130927] 694a0060 7d4a0074 794ad182 694a0001 <0b0a0000> 892d02a4 2f890000 40de0134

Signed-off-by: Scott Mayhew <smayhew@redhat.com>
Cc: stable@vger.kernel.org # 4.5+
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2017-12-15 14:31:50 -05:00
Markus Elfring 0671d8f108 nfs/write: Use common error handling code in nfs_lock_and_join_requests()
Add a jump target so that a bit of exception handling can be better reused
at the end of this function.

This issue was detected by using the Coccinelle software.

Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2017-11-17 16:43:50 -05:00
NeilBrown bf4b490597 NFS: various changes relating to reporting IO errors.
1/ remove 'start' and 'end' args from nfs_file_fsync_commit().
   They aren't used.

2/ Make nfs_context_set_write_error() a "static inline" in internal.h
   so we can...

3/ Use nfs_context_set_write_error() instead of mapping_set_error()
   if nfs_pageio_add_request() fails before sending any request.
   NFS generally keeps errors in the open_context, not the mapping,
   so this is more consistent.

4/ If filemap_write_and_write_range() reports any error, still
   check ctx->error.  The value in ctx->error is likely to be
   more useful.  As part of this, NFS_CONTEXT_ERROR_WRITE is
   cleared slightly earlier, before nfs_file_fsync_commit() is called,
   rather than at the start of that function.

Signed-off-by: NeilBrown <neilb@suse.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2017-09-11 22:28:56 -04:00
Chuck Lever 8224b2734a NFS: Add static NFS I/O tracepoints
Tools like tcpdump and rpcdebug can be very useful. But there are
plenty of environments where they are difficult or impossible to
use. For example, we've had customers report I/O failures during
workloads so heavy that collecting network traffic or enabling
RPC debugging are themselves onerous.

The kernel's static tracepoints are lightweight (less likely to
introduce timing changes) and efficient (the trace data is compact).
They also work in scenarios where capturing network traffic is not
possible due to lack of hardware support (some InfiniBand HCAs) or
where data or network privacy is a concern.

Introduce tracepoints that show when an NFS READ, WRITE, or COMMIT
is initiated, and when it completes. Record the arguments and
results of each operation, which are not shown by existing sunrpc
module's tracepoints.

For instance, the recorded offset and count can be used to match an
"initiate" event to a "done" event. If an NFS READ result returns
fewer bytes than requested or zero, seeing the EOF flag can be
probative. Seeing an NFS4ERR_BAD_STATEID result is also indication
of a particular class of problems. The timing information attached
to each event record can often be useful as well.

Usage example:

[root@manet tmp]# trace-cmd record -e nfs:*initiate* -e nfs:*done
/sys/kernel/debug/tracing/events/nfs/*initiate*/filter
/sys/kernel/debug/tracing/events/nfs/*done/filter
Hit Ctrl^C to stop recording
^CKernel buffer statistics:
  Note: "entries" are the entries left in the kernel ring buffer and are not
        recorded in the trace data. They should all be zero.

CPU: 0
entries: 0
overrun: 0
commit overrun: 0
bytes: 3680
oldest event ts:    78.367422
now ts:   100.124419
dropped events: 0
read events: 74

... and so on.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2017-09-11 22:20:38 -04:00
Trond Myklebust 1bd5d6d08e NFS: Count the bytes of skipped subrequests in nfs_lock_and_join_requests()
If we skip a subrequest due to a zero refcount, we should still count
the byte range that it covered so that we accurately reconstruct the
original request size.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2017-09-09 16:43:09 -04:00
Trond Myklebust 8b77484f2b NFS: Don't hold the group lock when calling nfs_release_request()
That can deadlock if this is the last reference since
nfs_page_group_destroy() calls nfs_page_group_sync_on_bit().
Note that even if the page was removed from the subpage list,
the req->wb_head could still be pointing to the old head.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2017-09-09 15:36:40 -04:00
Trond Myklebust 5d2a9d9dac NFS: Remove pnfs_generic_transfer_commit_list()
It's pretty much a duplicate of nfs_scan_commit_list() that also
clears the PG_COMMIT_TO_DS flag.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2017-09-09 12:51:40 -04:00
Trond Myklebust 137da553db NFS: nfs_lock_and_join_requests and nfs_scan_commit_list can deadlock
Since the commit list is not ordered, it is possible for nfs_scan_commit_list
to hold a request that nfs_lock_and_join_requests() is waiting for, while
at the same time trying to grab a request that nfs_lock_and_join_requests
already holds.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2017-09-09 12:28:01 -04:00
NeilBrown 237f8306c3 NFS: don't expect errors from mempool_alloc().
Commit fbe77c30e9 ("NFS: move rw_mode to nfs_pageio_header")
reintroduced some pointless code that commit 518662e0fc ("NFS: fix
usage of mempools.") had recently removed.

Remove it again.

Cc: Benjamin Coddington <bcodding@redhat.com>
Signed-off-by: NeilBrown <neilb@suse.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2017-09-06 12:31:15 -04:00
Trond Myklebust 7af7a5963c Merge branch 'bugfixes' 2017-08-20 13:04:12 -04:00
Trond Myklebust 3bde7afdab NFS: Remove unused parameter gfp_flags from nfs_pageio_init()
Now that the mirror allocation has been moved, the parameter can go.
Also remove the redundant symbol export.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2017-08-20 11:35:33 -04:00
Trond Myklebust 2ce209c42c NFS: Wait for requests that are locked on the commit list
If a request is on the commit list, but is locked, we will currently skip
it, which can lead to livelocking when the commit count doesn't reduce
to zero.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2017-08-15 11:54:48 -04:00
Trond Myklebust 4b9bb25b36 NFS: Switch to using mapping->private_lock for page writeback lookups.
Switch from using the inode->i_lock for this to avoid contention with
other metadata manipulation.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2017-08-15 11:54:48 -04:00
Trond Myklebust 5cb953d4b1 NFS: Use an atomic_long_t to count the number of commits
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2017-08-15 11:54:48 -04:00
Trond Myklebust a6b6d5b85a NFS: Use an atomic_long_t to count the number of requests
Rather than forcing us to take the inode->i_lock just in order to bump
the number.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2017-08-15 11:54:47 -04:00
Trond Myklebust e824f99ada NFSv4: Use a mutex to protect the per-inode commit lists
The commit lists can get very large, so using the inode->i_lock can
end up affecting general metadata performance.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2017-08-15 11:54:47 -04:00
Trond Myklebust b30d2f04c3 NFS: Refactor nfs_page_find_head_request()
Split out the 2 cases so that we can treat the locking differently.
The issue is that the locking in the pageswapcache cache is highly
linked to the commit list locking.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2017-08-15 11:54:47 -04:00
Trond Myklebust bd37d6fce1 NFSv4: Convert nfs_lock_and_join_requests() to use nfs_page_find_head_request()
Hide the locking from nfs_lock_and_join_requests() so that we can
separate out the requirements for swapcache pages.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2017-08-15 11:54:47 -04:00
Trond Myklebust 7e8a30f8b4 NFS: Fix up nfs_page_group_covers_page()
Fix up the test in nfs_page_group_covers_page(). The simplest implementation
is to check that we have a set of intersecting or contiguous subrequests
that connect page offset 0 to nfs_page_length(req->wb_page).

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2017-08-15 11:54:47 -04:00
Trond Myklebust 1344b7ea17 NFS: Remove unused parameter from nfs_page_group_lock()
nfs_page_group_lock() is now always called with the 'nonblock'
parameter set to 'false'.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2017-08-15 11:54:47 -04:00
Trond Myklebust 902a4c0046 NFS: Remove nfs_page_group_clear_bits()
At this point, we only expect ever to potentially see PG_REMOVE and
PG_TEARDOWN being set on the subrequests.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2017-08-15 11:54:47 -04:00
Trond Myklebust 5b2b5187fa NFS: Fix nfs_page_group_destroy() and nfs_lock_and_join_requests() race cases
Since nfs_page_group_destroy() does not take any locks on the requests
to be freed, we need to ensure that we don't inadvertently free the
request in nfs_destroy_unlinked_subrequests() while the last reference
is being released elsewhere.

Do this by:

1) Taking a reference to the request unless it is already being freed
2) Checking (under the page group lock) if PG_TEARDOWN is already set before
   freeing an unreferenced request in nfs_destroy_unlinked_subrequests()

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2017-08-15 11:54:47 -04:00
Trond Myklebust 74a6d4b5ae NFS: Further optimise nfs_lock_and_join_requests()
When locking the entire group in order to remove subrequests,
the locks are always taken in order, and with the page group
lock being taken after the page head is locked. The intention
is that:

1) The lock on the group head guarantees that requests may not
   be removed from the group (although new entries could be appended
   if we're not holding the group lock).
2) It is safe to drop and retake the page group lock while iterating
   through the list, in particular when waiting for a subrequest lock.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2017-08-15 11:54:47 -04:00
Trond Myklebust b5bab9bf91 NFS: Reduce inode->i_lock contention in nfs_lock_and_join_requests()
We should no longer need the inode->i_lock, now that we've
straightened out the request locking. The locking schema is now:

1) Lock page head request
2) Lock the page group
3) Lock the subrequests one by one

Note that there is a subtle race with nfs_inode_remove_request() due
to the fact that the latter does not lock the page head, when removing
it from the struct page. Only the last subrequest is locked, hence
we need to re-check that the PagePrivate(page) is still set after
we've locked all the subrequests.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2017-08-15 11:54:47 -04:00
Trond Myklebust 7e6cca6caf NFS: Remove page group limit in nfs_flush_incompatible()
nfs_try_to_update_request() should be able to cope now.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2017-08-15 11:54:47 -04:00
Trond Myklebust f6032f216f NFS: Teach nfs_try_to_update_request() to deal with request page_groups
Simplify the code, and avoid some flushes to disk.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2017-08-15 11:54:47 -04:00
Trond Myklebust b66aaa8dfe NFS: Fix the inode request accounting when pages have subrequests
Both nfs_destroy_unlinked_subrequests() and nfs_lock_and_join_requests()
manipulate the inode flags adjusting the NFS_I(inode)->nrequests.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2017-08-15 11:54:47 -04:00
Trond Myklebust 31a01f093e NFS: Don't unlock writebacks before declaring PG_WB_END
We don't want nfs_lock_and_join_requests() to start fiddling with
the request before the call to nfs_page_group_sync_on_bit().

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2017-08-15 11:54:46 -04:00
Trond Myklebust e14bebf6de NFS: Don't check request offset and size without holding a lock
Request offsets and sizes are not guaranteed to be stable unless you
are holding the request locked.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2017-08-15 11:54:46 -04:00
Trond Myklebust a0e265bc78 NFS: Fix an ABBA issue in nfs_lock_and_join_requests()
All other callers of nfs_page_group_lock() appear to already hold the
page lock on the head page, so doing it in the opposite order here
is inefficient, although not deadlock prone since we roll back all
locks on contention.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2017-08-15 11:54:46 -04:00
Trond Myklebust 7cb9cd9aa2 NFS: Fix a reference and lock leak in nfs_lock_and_join_requests()
Yes, this is a situation that should never happen (hence the WARN_ON)
but we should still ensure that we free up the locks and references to
the faulty pages.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2017-08-15 11:54:46 -04:00
Trond Myklebust 1403390d83 NFS: Reduce lock contention in nfs_try_to_update_request()
Micro-optimisation to move the lockless check into the for(;;) loop.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2017-08-15 11:54:46 -04:00
Trond Myklebust 82749dd4ef NFS: Reduce lock contention in nfs_page_find_head_request()
Add a lockless check for whether or not the page might be carrying
an existing writeback before we grab the inode->i_lock.

Reported-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2017-08-15 11:54:46 -04:00
Trond Myklebust 6d17d653c9 NFS: Simplify page writeback
We don't expect the page header lock to ever be held across I/O, so
it should always be safe to wait for it, even if we're doing nonblocking
writebacks.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2017-08-15 11:54:46 -04:00
Trond Myklebust 1a4edf0f46 NFS: Fix commit policy for non-blocking calls to nfs_write_inode()
Now that the writes will schedule a commit on their own, we don't
need nfs_write_inode() to schedule one if there are outstanding
writes, and we're being called in non-blocking mode.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2017-07-13 15:58:05 -04:00
Trond Myklebust 919e3bd9a8 NFS: Ensure we commit after writeback is complete
If the page cache is being flushed, then we want to ensure that we
do start a commit once the pages are done being flushed.
If we just wait until all I/O is done to that file, we can end up
livelocking until the balance_dirty_pages() mechanism puts its
foot down and forces I/O to stop.
So instead we do more or less the same thing that O_DIRECT does,
and set up a counter to tell us when the flush is done,

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2017-07-13 15:58:05 -04:00
Linus Torvalds 73ccb023a2 NFS client updates for Linux 4.12
Highlights include:
 
 Stable bugfixes:
 - Fix use after free in write error path
 - Use GFP_NOIO for two allocations in writeback
 - Fix a hang in OPEN related to server reboot
 - Check the result of nfs4_pnfs_ds_connect
 - Fix an rcu lock leak
 
 Features:
 - Removal of the unmaintained and unused OSD pNFS layout
 - Cleanup and removal of lots of unnecessary dprintk()s
 - Cleanup and removal of some memory failure paths now that
   GFP_NOFS is guaranteed to never fail.
 - Remove the v3-only data server limitation on pNFS/flexfiles
 
 Bugfixes:
 - RPC/RDMA connection handling bugfixes
 - Copy offload: fixes to ensure the copied data is COMMITed to disk.
 - Readdir: switch back to using the ->iterate VFS interface
 - File locking fixes from Ben Coddington
 - Various use-after-free and deadlock issues in pNFS
 - Write path bugfixes
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Merge tag 'nfs-for-4.12-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs

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

  Stable bugfixes:
   - Fix use after free in write error path
   - Use GFP_NOIO for two allocations in writeback
   - Fix a hang in OPEN related to server reboot
   - Check the result of nfs4_pnfs_ds_connect
   - Fix an rcu lock leak

  Features:
   - Removal of the unmaintained and unused OSD pNFS layout
   - Cleanup and removal of lots of unnecessary dprintk()s
   - Cleanup and removal of some memory failure paths now that GFP_NOFS
     is guaranteed to never fail.
   - Remove the v3-only data server limitation on pNFS/flexfiles

  Bugfixes:
   - RPC/RDMA connection handling bugfixes
   - Copy offload: fixes to ensure the copied data is COMMITed to disk.
   - Readdir: switch back to using the ->iterate VFS interface
   - File locking fixes from Ben Coddington
   - Various use-after-free and deadlock issues in pNFS
   - Write path bugfixes"

* tag 'nfs-for-4.12-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs: (89 commits)
  pNFS/flexfiles: Always attempt to call layoutstats when flexfiles is enabled
  NFSv4.1: Work around a Linux server bug...
  NFS append COMMIT after synchronous COPY
  NFSv4: Fix exclusive create attributes encoding
  NFSv4: Fix an rcu lock leak
  nfs: use kmap/kunmap directly
  NFS: always treat the invocation of nfs_getattr as cache hit when noac is on
  Fix nfs_client refcounting if kmalloc fails in nfs4_proc_exchange_id and nfs4_proc_async_renew
  NFSv4.1: RECLAIM_COMPLETE must handle NFS4ERR_CONN_NOT_BOUND_TO_SESSION
  pNFS: Fix NULL dereference in pnfs_generic_alloc_ds_commits
  pNFS: Fix a typo in pnfs_generic_alloc_ds_commits
  pNFS: Fix a deadlock when coalescing writes and returning the layout
  pNFS: Don't clear the layout return info if there are segments to return
  pNFS: Ensure we commit the layout if it has been invalidated
  pNFS: Don't send COMMITs to the DSes if the server invalidated our layout
  pNFS/flexfiles: Fix up the ff_layout_write_pagelist failure path
  pNFS: Ensure we check layout validity before marking it for return
  NFS4.1 handle interrupted slot reuse from ERR_DELAY
  NFSv4: check return value of xdr_inline_decode
  nfs/filelayout: fix NULL pointer dereference in fl_pnfs_update_layout()
  ...
2017-05-10 13:03:38 -07:00
Olga Kornievskaia e092693443 NFS append COMMIT after synchronous COPY
Instead of messing with the commit path which has been causing issues,
add a COMMIT op after the COPY and ask for stable copies in the first
space.

It saves a round trip, since after the COPY, the client sends a COMMIT
anyway.

Signed-off-by: Olga Kornievskaia <kolga@netapp.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2017-05-08 19:01:06 -04:00
Trond Myklebust c373fff7bd NFSv4: Don't special case "launder"
If the client receives a fatal server error from nfs_pageio_add_request(),
then we should always truncate the page on which the error occurred.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2017-04-26 13:03:04 -04:00
Trond Myklebust a6598813a4 NFS: Don't write back further requests if there is a pending write error
If the server has already returned a fatal write error that the user
has not yet received on this file, then don't write back the other pages.
Instead, act as if they have been sent, and have returned with the same
error.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2017-04-25 15:42:34 -04:00
Jan Kara 0db10944a7 nfs: Convert to separately allocated bdi
Allocate struct backing_dev_info separately instead of embedding it
inside the superblock. This unifies handling of bdi among users.

CC: Anna Schumaker <anna.schumaker@netapp.com>
CC: linux-nfs@vger.kernel.org
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jan Kara <jack@suse.cz>
Acked-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-04-20 12:09:55 -06:00
Benjamin Coddington fbe77c30e9 NFS: move rw_mode to nfs_pageio_header
Let's try to have it in a cacheline in nfs4_proc_pgio_rpc_prepare().

Signed-off-by: Benjamin Coddington <bcodding@redhat.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2017-04-20 14:00:41 -04:00
Fred Isaman 1f84ccdf37 NFS: Fix use after free in write error path
Signed-off-by: Fred Isaman <fred.isaman@gmail.com>
Fixes: 0bcbf039f6 ("nfs: handle request add failure properly")
Cc: stable@vger.kernel.org # v4.5+
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2017-04-20 13:51:52 -04:00
NeilBrown 518662e0fc NFS: fix usage of mempools.
When passed GFP flags that allow sleeping (such as
GFP_NOIO), mempool_alloc() will never return NULL, it will
wait until memory is available.

This means that we don't need to handle failure, but that we
do need to ensure one thread doesn't call mempool_alloc()
twice on the one pool without queuing or freeing the first
allocation.  If multiple threads did this during times of
high memory pressure, the pool could be exhausted and a
deadlock could result.

pnfs_generic_alloc_ds_commits() attempts to allocate from
the nfs_commit_mempool while already holding an allocation
from that pool.  This is not safe.  So change
nfs_commitdata_alloc() to take a flag that indicates whether
failure is acceptable.

In pnfs_generic_alloc_ds_commits(), accept failure and
handle it as we currently do.  Else where, do not accept
failure, and do not handle it.

Even when failure is acceptable, we want to succeed if
possible.  That means both
 - using an entry from the pool if there is one
 - waiting for direct reclaim is there isn't.

We call mempool_alloc(GFP_NOWAIT) to achieve the first, then
kmem_cache_alloc(GFP_NOIO|__GFP_NORETRY) to achieve the
second.  Each of these can fail, but together they do the
best they can without blocking indefinitely.

The objects returned by kmem_cache_alloc() will still be freed
by mempool_free().  This is safe as mempool_alloc() uses
exactly the same function to allocate objects (since the mempool
was created with mempool_create_slab_pool()).  The object returned
by mempool_alloc() and kmem_cache_alloc() are indistinguishable
so mempool_free() will handle both identically, either adding to the
pool or calling kmem_cache_free().

Also, don't test for failure when allocating from
nfs_wdata_mempool.

Signed-off-by: NeilBrown <neilb@suse.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2017-04-20 13:44:05 -04:00
Kinglong Mee 38a33101dd NFS: fix the fault nrequests decreasing for nfs_inode COPY
The nfs_commit_file for NFSv4.2's COPY operation goes through
the commit path for normal WRITE, but without increase nrequests,
so, the nrequests decreased in nfs_commit_release_pages is fault.
After that, the nrequests will be wrong.

[ 5670.299881] ------------[ cut here ]------------
[ 5670.300295] WARNING: CPU: 0 PID: 27656 at fs/nfs/inode.c:127 nfs_clear_inode+0x66/0x90 [nfs]
[ 5670.300558] Modules linked in: nfsv4(E) nfs(E) fscache(E) tun bridge stp llc fuse ip_set nfnetlink vmw_vsock_vmci_transport vsock snd_seq_midi snd_seq_midi_event ppdev f2fs coretemp crct10dif_pclmul crc32_pclmul ghash_clmulni_intel snd_ens1371 intel_rapl_perf gameport snd_ac97_codec vmw_balloon ac97_bus snd_seq snd_pcm joydev snd_rawmidi snd_timer snd_seq_device snd soundcore nfit parport_pc parport acpi_cpufreq tpm_tis tpm_tis_core tpm i2c_piix4 vmw_vmci shpchp nfsd auth_rpcgss nfs_acl lockd grace sunrpc xfs libcrc32c vmwgfx drm_kms_helper ttm drm e1000 crc32c_intel mptspi scsi_transport_spi serio_raw mptscsih mptbase ata_generic pata_acpi fjes [last unloaded: fscache]
[ 5670.302925] CPU: 0 PID: 27656 Comm: umount.nfs4 Tainted: G        W   E   4.11.0-rc1+ #519
[ 5670.303292] Hardware name: VMware, Inc. VMware Virtual Platform/440BX Desktop Reference Platform, BIOS 6.00 07/02/2015
[ 5670.304094] Call Trace:
[ 5670.304510]  dump_stack+0x63/0x86
[ 5670.304917]  __warn+0xcb/0xf0
[ 5670.305276]  warn_slowpath_null+0x1d/0x20
[ 5670.305661]  nfs_clear_inode+0x66/0x90 [nfs]
[ 5670.306093]  nfs4_evict_inode+0x61/0x70 [nfsv4]
[ 5670.306480]  evict+0xbb/0x1c0
[ 5670.306888]  dispose_list+0x4d/0x70
[ 5670.307233]  evict_inodes+0x178/0x1a0
[ 5670.307579]  generic_shutdown_super+0x44/0xf0
[ 5670.307985]  nfs_kill_super+0x21/0x40 [nfs]
[ 5670.308325]  deactivate_locked_super+0x43/0x70
[ 5670.308698]  deactivate_super+0x5a/0x60
[ 5670.309036]  cleanup_mnt+0x3f/0x90
[ 5670.309407]  __cleanup_mnt+0x12/0x20
[ 5670.309837]  task_work_run+0x80/0xa0
[ 5670.310162]  exit_to_usermode_loop+0x89/0x90
[ 5670.310497]  syscall_return_slowpath+0xaa/0xb0
[ 5670.310875]  entry_SYSCALL_64_fastpath+0xa7/0xa9
[ 5670.311197] RIP: 0033:0x7f1bb3617fe7
[ 5670.311545] RSP: 002b:00007ffecbabb828 EFLAGS: 00000206 ORIG_RAX: 00000000000000a6
[ 5670.311906] RAX: 0000000000000000 RBX: 0000000001dca1f0 RCX: 00007f1bb3617fe7
[ 5670.312239] RDX: 000000000000000c RSI: 0000000000000001 RDI: 0000000001dc83c0
[ 5670.312653] RBP: 0000000001dc83c0 R08: 0000000000000001 R09: 0000000000000000
[ 5670.312998] R10: 0000000000000755 R11: 0000000000000206 R12: 00007ffecbabc66a
[ 5670.313335] R13: 0000000001dc83a0 R14: 0000000000000000 R15: 0000000000000000
[ 5670.313758] ---[ end trace bf4bfe7764e4eb40 ]---

Cc: linux-kernel@vger.kernel.org
Fixes: 67911c8f18 ("NFS: Add nfs_commit_file()")
Signed-off-by: Kinglong Mee <kinglongmee@gmail.com>
Cc: stable@vger.kernel.org # 4.7+
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2017-03-17 16:03:51 -04:00
Nicholas Piggin 600424e3d9 nfs: no PG_private waiters remain, remove waker
Since commit 4f52b6bb ("NFS: Don't call COMMIT in ->releasepage()"),
no tasks wait on PagePrivate, so the wake introduced in commit 95905446
("NFS: avoid deadlocks with loop-back mounted NFS filesystems.") can
be removed.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2017-02-08 17:02:44 -05:00