Граф коммитов

275 Коммитов

Автор SHA1 Сообщение Дата
Trond Myklebust 3731d44bba NFSv4: Fix an Oops in pnfs_mark_request_commit() when doing O_DIRECT
Fix an Oopsable condition in pnfs_mark_request_commit() when we're
putting a set of writes on the commit list to reschedule them after a
failed pNFS attempt.

Fixes: 9c455a8c1e ("NFS/pNFS: Clean up pNFS commit operations")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2021-06-13 19:36:49 -04:00
Linus Torvalds 37711e5e23 NFS client updates for Linux 5.9
Highlights include:
 
 Stable fixes:
 - pNFS: Don't return layout segments that are being used for I/O
 - pNFS: Don't move layout segments off the active list when being used for I/O
 
 Features:
 - NFS: Add support for user xattrs through the NFSv4.2 protocol
 - NFS: Allow applications to speed up readdir+statx() using AT_STATX_DONT_SYNC
 - NFSv4.0 allow nconnect for v4.0
 
 Bugfixes and cleanups:
 - nfs: ensure correct writeback errors are returned on close()
 - nfs: nfs_file_write() should check for writeback errors
 - nfs: Fix getxattr kernel panic and memory overflow
 - NFS: Fix the pNFS/flexfiles mirrored read failover code
 - SUNRPC: dont update timeout value on connection reset
 - freezer: Add unsafe versions of freezable_schedule_timeout_interruptible for NFS
 - sunrpc: destroy rpc_inode_cachep after unregister_filesystem
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Merge tag 'nfs-for-5.9-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs

Pull NFS client updates from Trond Myklebust:
 "Stable fixes:
   - pNFS: Don't return layout segments that are being used for I/O
   - pNFS: Don't move layout segments off the active list when being used for I/O

  Features:
   - NFS: Add support for user xattrs through the NFSv4.2 protocol
   - NFS: Allow applications to speed up readdir+statx() using AT_STATX_DONT_SYNC
   - NFSv4.0 allow nconnect for v4.0

  Bugfixes and cleanups:
   - nfs: ensure correct writeback errors are returned on close()
   - nfs: nfs_file_write() should check for writeback errors
   - nfs: Fix getxattr kernel panic and memory overflow
   - NFS: Fix the pNFS/flexfiles mirrored read failover code
   - SUNRPC: dont update timeout value on connection reset
   - freezer: Add unsafe versions of freezable_schedule_timeout_interruptible for NFS
   - sunrpc: destroy rpc_inode_cachep after unregister_filesystem"

* tag 'nfs-for-5.9-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs: (32 commits)
  NFS: Fix flexfiles read failover
  fs: nfs: delete repeated words in comments
  rpc_pipefs: convert comma to semicolon
  nfs: Fix getxattr kernel panic and memory overflow
  NFS: Don't return layout segments that are in use
  NFS: Don't move layouts to plh_return_segs list while in use
  NFS: Add layout segment info to pnfs read/write/commit tracepoints
  NFS: Add tracepoints for layouterror and layoutstats.
  NFS: Report the stateid + status in trace_nfs4_layoutreturn_on_close()
  SUNRPC dont update timeout value on connection reset
  nfs: nfs_file_write() should check for writeback errors
  nfs: ensure correct writeback errors are returned on close()
  NFSv4.2: xattr cache: get rid of cache discard work queue
  NFS: remove redundant initialization of variable result
  NFSv4.0 allow nconnect for v4.0
  freezer: Add unsafe versions of freezable_schedule_timeout_interruptible for NFS
  sunrpc: destroy rpc_inode_cachep after unregister_filesystem
  NFSv4.2: add client side xattr caching.
  NFSv4.2: hook in the user extended attribute handlers
  NFSv4.2: add the extended attribute proc functions.
  ...
2020-08-15 08:26:55 -07:00
Colin Ian King 9a74a2b87f NFS: remove redundant initialization of variable result
The variable result is being initialized with a value that is never read
and it is being updated later with a new value.  The initialization is
redundant and can be removed.

Addresses-Coverity: ("Unused value")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2020-07-28 11:04:06 -04:00
Olga Kornievskaia 65caafd0d2 SUNRPC reverting d03727b248 ("NFSv4 fix CLOSE not waiting for direct IO compeletion")
Reverting commit d03727b248 "NFSv4 fix CLOSE not waiting for
direct IO compeletion". This patch made it so that fput() by calling
inode_dio_done() in nfs_file_release() would wait uninterruptably
for any outstanding directIO to the file (but that wait on IO should
be killable).

The problem the patch was also trying to address was REMOVE returning
ERR_ACCESS because the file is still opened, is supposed to be resolved
by server returning ERR_FILE_OPEN and not ERR_ACCESS.

Signed-off-by: Olga Kornievskaia <kolga@netapp.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2020-07-17 14:47:38 -04:00
Olga Kornievskaia d03727b248 NFSv4 fix CLOSE not waiting for direct IO compeletion
Figuring out the root case for the REMOVE/CLOSE race and
suggesting the solution was done by Neil Brown.

Currently what happens is that direct IO calls hold a reference
on the open context which is decremented as an asynchronous task
in the nfs_direct_complete(). Before reference is decremented,
control is returned to the application which is free to close the
file. When close is being processed, it decrements its reference
on the open_context but since directIO still holds one, it doesn't
sent a close on the wire. It returns control to the application
which is free to do other operations. For instance, it can delete a
file. Direct IO is finally releasing its reference and triggering
an asynchronous close. Which races with the REMOVE. On the server,
REMOVE can be processed before the CLOSE, failing the REMOVE with
EACCES as the file is still opened.

Signed-off-by: Olga Kornievskaia <kolga@netapp.com>
Suggested-by: Neil Brown <neilb@suse.com>
CC: stable@vger.kernel.org
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2020-06-26 08:43:14 -04:00
Chuck Lever ba838a75e7 NFS: Fix direct WRITE throughput regression
I measured a 50% throughput regression for large direct writes.

The observed on-the-wire behavior is that the client sends every
NFS WRITE twice: once as an UNSTABLE WRITE plus a COMMIT, and once
as a FILE_SYNC WRITE.

This is because the nfs_write_match_verf() check in
nfs_direct_commit_complete() fails for every WRITE.

Buffered writes use nfs_write_completion(), which sets req->wb_verf
correctly. Direct writes use nfs_direct_write_completion(), which
does not set req->wb_verf at all. This leaves req->wb_verf set to
all zeroes for every direct WRITE, and thus
nfs_direct_commit_completion() always sets NFS_ODIRECT_RESCHED_WRITES.

This fix appears to restore nearly all of the lost performance.

Fixes: 1f28476dcb ("NFS: Fix O_DIRECT commit verifier handling")
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2020-06-11 13:33:48 -04:00
Colin Ian King 86b936672e NFS: remove redundant initialization of variable result
The variable result is being initialized with a value that is never read
and it is being updated later with a new value.  The initialization is
redundant and can be removed.

Addresses-Coverity: ("Unused value")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2020-06-11 13:33:48 -04:00
Trond Myklebust ed5d588fe4 NFS: Try to join page groups before an O_DIRECT retransmission
If we have to retransmit requests, try to join their page groups
first.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2020-04-01 13:37:57 -04:00
Trond Myklebust f02cec9d33 NFS: Fix a request reference leak in nfs_direct_write_clear_reqs()
nfs_direct_write_scan_commit_list() will lock the request and bump
the reference count, but we also need to account for the reference
that was taken when we initially added the request to the commit list.

Fixes: fb5f7f20cd ("NFS: commit errors should be fatal")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2020-04-01 13:37:56 -04:00
Trond Myklebust 9c455a8c1e NFS/pNFS: Clean up pNFS commit operations
Move the pNFS commit related operations into a separate structure
that can be carried by the pnfs_ds_commit_info.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2020-03-27 16:34:35 -04:00
Trond Myklebust 0aa647b736 NFS: Remove bucket array from struct pnfs_ds_commit_info
Remove the unused bucket array in struct pnfs_ds_commit_info.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2020-03-27 16:34:35 -04:00
Trond Myklebust 1f28476dcb NFS: Fix O_DIRECT commit verifier handling
Instead of trying to save the commit verifiers and checking them against
previous writes, adopt the same strategy as for buffered writes, of
just checking the verifiers at commit time.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2020-03-27 16:34:34 -04:00
Trond Myklebust fb5f7f20cd NFS: commit errors should be fatal
Fix the O_DIRECT code to avoid retries if the COMMIT fails with a fatal
error.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2020-03-27 16:34:34 -04:00
Trond Myklebust 18f4129696 NFS/pNFS: Allow O_DIRECT to release the DS commitinfo
Add a pNFS callback to allow the O_DIRECT code to release the DS
commitinfo when freeing the dreq.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2020-03-27 16:34:34 -04:00
Trond Myklebust c21e716884 NFSv4/pnfs: Support a list of commit arrays in struct pnfs_ds_commit_info
When we have multiple layout segments with different lists of mirrored
data, we need to track the commits on a per layout segment basis.
This patch adds a list to support this tracking in struct
pnfs_ds_commit_info.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2020-03-27 16:34:34 -04:00
Misono Tomohiro 8605cf0e85 NFS: direct.c: Fix memory leak of dreq when nfs_get_lock_context fails
When dreq is allocated by nfs_direct_req_alloc(), dreq->kref is
initialized to 2. Therefore we need to call nfs_direct_req_release()
twice to release the allocated dreq. Usually it is called in
nfs_file_direct_{read, write}() and nfs_direct_complete().

However, current code only calls nfs_direct_req_relese() once if
nfs_get_lock_context() fails in nfs_file_direct_{read, write}().
So, that case would result in memory leak.

Fix this by adding the missing call.

Signed-off-by: Misono Tomohiro <misono.tomohiro@jp.fujitsu.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2020-03-22 16:47:58 -04:00
Trond Myklebust 4daaeba938 NFS: Fix nfs_direct_write_reschedule_io()
The 'hdr->good_bytes' is defined as the number of bytes we expect to
read or write starting at offset hdr->io_start. In the case of a partial
read/write we may end up adjusting hdr->args.offset and hdr->args.count
to skip I/O for data that was already read/written, and so we must ensure
the calculation takes that into account.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2020-01-15 10:54:33 -05:00
Trond Myklebust 221203ce64 NFS/pnfs: Fix pnfs_generic_prepare_to_resend_writes()
Instead of making assumptions about the commit verifier contents, change
the commit code to ensure we always check that the verifier was set
by the XDR code.

Fixes: f54bcf2ece ("pnfs: Prepare for flexfiles by pulling out common code")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2020-01-15 10:54:32 -05:00
Trond Myklebust 0b57484779 NFS: Remove redundant mirror tracking in O_DIRECT
We no longer need the extra mirror length tracking in the O_DIRECT code,
as we are able to track the maximum contiguous length in dreq->max_count.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2019-10-09 11:45:59 -04:00
Trond Myklebust 031d73ed76 NFS: Fix O_DIRECT accounting of number of bytes read/written
When a series of O_DIRECT reads or writes are truncated, either due to
eof or due to an error, then we should return the number of contiguous
bytes that were received/sent starting at the offset specified by the
application.

Currently, we are failing to correctly check contiguity, and so we're
failing the generic/465 in xfstests when the race between the read
and write RPCs causes the file to get extended while the 2 reads are
outstanding. If the first read RPC call wins the race and returns with
eof set, we should treat the second read RPC as being truncated.

Reported-by: Su Yanjun <suyj.fnst@cn.fujitsu.com>
Fixes: 1ccbad9f9f ("nfs: fix DIO good bytes calculation")
Cc: stable@vger.kernel.org # 4.1+
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2019-10-09 11:45:59 -04:00
Trond Myklebust eb2c50da9e NFS: Ensure O_DIRECT reports an error if the bytes read/written is 0
If the attempt to resend the I/O results in no bytes being read/written,
we must ensure that we report the error.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Fixes: 0a00b77b33 ("nfs: mirroring support for direct io")
Cc: stable@vger.kernel.org # v3.20+
2019-08-19 08:56:04 -04:00
Thomas Gleixner 457c899653 treewide: Add SPDX license identifier for missed files
Add SPDX license identifiers to all files which:

 - Have no license information of any form

 - Have EXPORT_.*_SYMBOL_GPL inside which was used in the
   initial scan/conversion to ignore the file

These files fall under the project license, GPL v2 only. The resulting SPDX
license identifier is:

  GPL-2.0-only

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-21 10:50:45 +02:00
Trond Myklebust 33344e0f7e pNFS: Add tracking to limit the number of pNFS retries
When the client is reading or writing using pNFS, and hits an error
on the DS, then it typically sends a LAYOUTERROR and/or LAYOUTRETURN
to the MDS, before redirtying the failed pages, and going for a new
round of reads/writebacks. The problem is that if the server has no
way to fix the DS, then we may need a way to interrupt this loop
after a set number of attempts have been made.
This patch adds an optional module parameter that allows the admin
to specify how many times to retry the read/writeback process before
failing with a fatal error.
The default behaviour is to retry forever.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2019-04-25 14:18:14 -04:00
Trond Myklebust 28b1d3f5a7 NFS: Remove unused argument from nfs_create_request()
All the callers of nfs_create_request() are now creating page group
heads, so we can remove the redundant 'last' page argument.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2019-04-25 14:18:14 -04:00
Trond Myklebust df3accb849 NFS: Pass error information to the pgio error cleanup routine
Allow the caller to pass error information when cleaning up a failed
I/O request so that we can conditionally take action to cancel the
request altogether if the error turned out to be fatal.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2019-02-20 15:14:20 -05:00
Trond Myklebust 078b5fd92c NFS: Clean up list moves of struct nfs_page
In several places we're just moving the struct nfs_page from one list to
another by first removing from the existing list, then adding to the new
one.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2019-02-20 15:14:20 -05:00
Dave Kleikamp ad3cba223a nfs: don't dirty kernel pages read by direct-io
When we use direct_IO with an NFS backing store, we can trigger a
WARNING in __set_page_dirty(), as below, since we're dirtying the page
unnecessarily in nfs_direct_read_completion().

To fix, replicate the logic in commit 53cbf3b157 ("fs: direct-io:
don't dirtying pages for ITER_BVEC/ITER_KVEC direct read").

Other filesystems that implement direct_IO handle this; most use
blockdev_direct_IO(). ceph and cifs have similar logic.

mount 127.0.0.1:/export /nfs
dd if=/dev/zero of=/nfs/image bs=1M count=200
losetup --direct-io=on -f /nfs/image
mkfs.btrfs /dev/loop0
mount -t btrfs /dev/loop0 /mnt/

kernel: WARNING: CPU: 0 PID: 8067 at fs/buffer.c:580 __set_page_dirty+0xaf/0xd0
kernel: Modules linked in: loop(E) nfsv3(E) rpcsec_gss_krb5(E) nfsv4(E) dns_resolver(E) nfs(E) fscache(E) nfsd(E) auth_rpcgss(E) nfs_acl(E) lockd(E) grace(E) fuse(E) tun(E) ip6t_rpfilter(E) ipt_REJECT(E) nf_
kernel:  snd_seq(E) snd_seq_device(E) snd_pcm(E) video(E) snd_timer(E) snd(E) soundcore(E) ip_tables(E) xfs(E) libcrc32c(E) sd_mod(E) sr_mod(E) cdrom(E) ata_generic(E) pata_acpi(E) crc32c_intel(E) ahci(E) li
kernel: CPU: 0 PID: 8067 Comm: kworker/0:2 Tainted: G            E     4.20.0-rc1.master.20181111.ol7.x86_64 #1
kernel: Hardware name: innotek GmbH VirtualBox/VirtualBox, BIOS VirtualBox 12/01/2006
kernel: Workqueue: nfsiod rpc_async_release [sunrpc]
kernel: RIP: 0010:__set_page_dirty+0xaf/0xd0
kernel: Code: c3 48 8b 02 f6 c4 04 74 d4 48 89 df e8 ba 05 f7 ff 48 89 c6 eb cb 48 8b 43 08 a8 01 75 1f 48 89 d8 48 8b 00 a8 04 74 02 eb 87 <0f> 0b eb 83 48 83 e8 01 eb 9f 48 83 ea 01 0f 1f 00 eb 8b 48 83 e8
kernel: RSP: 0000:ffffc1c8825b7d78 EFLAGS: 00013046
kernel: RAX: 000fffffc0020089 RBX: fffff2b603308b80 RCX: 0000000000000001
kernel: RDX: 0000000000000001 RSI: ffff9d11478115c8 RDI: ffff9d11478115d0
kernel: RBP: ffffc1c8825b7da0 R08: 0000646f6973666e R09: 8080808080808080
kernel: R10: 0000000000000001 R11: 0000000000000000 R12: ffff9d11478115d0
kernel: R13: ffff9d11478115c8 R14: 0000000000003246 R15: 0000000000000001
kernel: FS:  0000000000000000(0000) GS:ffff9d115ba00000(0000) knlGS:0000000000000000
kernel: CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
kernel: CR2: 00007f408686f640 CR3: 0000000104d8e004 CR4: 00000000000606f0
kernel: DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
kernel: DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
kernel: Call Trace:
kernel:  __set_page_dirty_buffers+0xb6/0x110
kernel:  set_page_dirty+0x52/0xb0
kernel:  nfs_direct_read_completion+0xc4/0x120 [nfs]
kernel:  nfs_pgio_release+0x10/0x20 [nfs]
kernel:  rpc_free_task+0x30/0x70 [sunrpc]
kernel:  rpc_async_release+0x12/0x20 [sunrpc]
kernel:  process_one_work+0x174/0x390
kernel:  worker_thread+0x4f/0x3e0
kernel:  kthread+0x102/0x140
kernel:  ? drain_workqueue+0x130/0x130
kernel:  ? kthread_stop+0x110/0x110
kernel:  ret_from_fork+0x35/0x40
kernel: ---[ end trace 01341980905412c9 ]---

Signed-off-by: Dave Kleikamp <dave.kleikamp@oracle.com>
Signed-off-by: Santosh Shilimkar <santosh.shilimkar@oracle.com>

[forward-ported to v4.20]
Signed-off-by: Calum Mackay <calum.mackay@oracle.com>
Reviewed-by: Dave Kleikamp <dave.kleikamp@oracle.com>
Reviewed-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2018-12-02 09:43:56 -05:00
NeilBrown 46483c2ea4 NFS: Use an appropriate work queue for direct-write completion
When a direct-write completes, a work_struct is schedule to handle
the completion.
When NFS is being used for swap, the direct write might be a swap-out,
so memory allocation can block until the write completes.
The work queue currently used is not WQ_MEM_RECLAIM, so tasks
can block waiting for memory - this leads to deadlock.

So use nfsiod_workqueue instead.  This will always have a running
thread, and work items should never block waiting for memory.

Signed-off-by: Neil Brown <neilb@suse.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2018-08-08 17:07:38 -04:00
Trond Myklebust d9ee65539d NFS: Fix an incorrect type in struct nfs_direct_req
The start offset needs to be of type loff_t.

Fixed: 5fadeb47dc ("nfs: count DIO good bytes correctly with mirroring")
Cc: stable@vger.kernel.org # v4.0+
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2018-03-08 12:56:31 -05:00
J. Bruce Fields 1b8d97b0a8 NFS: commit direct writes even if they fail partially
If some of the WRITE calls making up an O_DIRECT write syscall fail,
we neglect to commit, even if some of the WRITEs succeed.

We also depend on the commit code to free the reference count on the
nfs_page taken in the "if (request_commit)" case at the end of
nfs_direct_write_completion().  The problem was originally noticed
because ENOSPC's encountered partway through a write would result in a
closed file being sillyrenamed when it should have been unlinked.

Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Cc: stable@vger.kernel.org
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2018-01-16 10:13:23 -05:00
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
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
Anna Schumaker fe4f844d49 NFS: Clean up nfs_direct_commit_complete()
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2017-04-20 13:39:33 -04:00
Anna Schumaker beeb533801 NFS: Remove nfs_direct_readpage_release()
Just remove the function and have the caller use nfs_release_request()
instead.

Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2017-04-20 13:39:33 -04:00
Al Viro 85128b2be6 fix nfs O_DIRECT advancing iov_iter too much
It leaves the iterator advanced by the amount of IO it has requested
instead of the amount actually transferred.  Among other things,
that confuses the hell out of generic_file_splice_read().

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2017-04-17 14:23:20 -04:00
Linus Torvalds 7c0f6ba682 Replace <asm/uaccess.h> with <linux/uaccess.h> globally
This was entirely automated, using the script by Al:

  PATT='^[[:blank:]]*#[[:blank:]]*include[[:blank:]]*<asm/uaccess.h>'
  sed -i -e "s!$PATT!#include <linux/uaccess.h>!" \
        $(git grep -l "$PATT"|grep -v ^include/linux/uaccess.h)

to do the replacement at the end of the merge window.

Requested-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-12-24 11:46:01 -08:00
Anna Schumaker 4d3b55d3c7 NFS: Remove unused argument from nfs_direct_write_complete()
This parameter hasn't been used since 2a009ec9 (Linux 3.13-rc3), so
let's remove it from this function.

Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2016-12-01 17:50:37 -05:00
Daniel Wagner 024de8f1ad NFS: direct: use complete() instead of complete_all()
There is only one waiter for the completion, therefore there
is no need to use complete_all(). Let's make that clear by
using complete() instead of complete_all().

nfs_file_direct_write() or nfs_file_direct_read() allocated a request
object via nfs_direct_req_alloc(), which initializes the
completion. The request object then is freed later in the exit path.
Between the initialization and the release either
nfs_direct_write_schedule_iovec() resp
nfs_direct_read_schedule_iovec() are called which will asynchronously
process the request. The calling function waits via nfs_direct_wait()
till the async work has been done. Thus there is only one waiter on
the completion.

nfs_direct_pgio_init() and nfs_direct_read_completion() are passed via
function pointers to nfs pageio. The first function does a ref
counting (get_dreq() and put_dreq()) which ensures that
nfs_direct_read_completion() and nfs_direct_read_schedule_iovec() only
call the completion path once.

The usage pattern of the completion is:

waiter context                          waker context

nfs_file_direct_write()
  dreq = nfs_direct_req_alloc()
    init_completion()
  nfs_direct_write_schedule_iovec()
  nfs_direct_wait()
    wait_for_completion_killable()

                                        nfs_direct_write_schedule_work()
                                          nfs_direct_complete()
                                            complete()

nfs_file_direct_read()
  dreq = nfs_direct_req_all()
    init_completion()
  nfs_direct_read_schedule_iovec()
  nfs_direct_wait()
    wait_for_completion_killable()
                                        nfs_direct_read_schedule_iovec()
                                          nfs_direct_complete()
                                            complete()

                                        nfs_direct_read_completion()
                                          nfs_direct_complete()
                                            complete()

Signed-off-by: Daniel Wagner <daniel.wagner@bmw-carit.de>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2016-09-23 09:14:16 -04:00
Linus Torvalds 7f155c7026 NFS client updates for Linux 4.8
Highlights include:
 
 Stable bugfixes:
  - nfs: don't create zero-length requests
  - Several LAYOUTGET bugfixes
 
 Features:
  - Several performance related features
    - More aggressive caching when we can rely on close-to-open cache
      consistency
    - Remove serialisation of O_DIRECT reads and writes
    - Optimise several code paths to not flush to disk unnecessarily. However
      allow for the idiosyncracies of pNFS for those layout types that need
      to issue a LAYOUTCOMMIT before the metadata can be updated on the server.
    - SUNRPC updates to the client data receive path
  - pNFS/SCSI support RH/Fedora dm-mpath device nodes
  - pNFS files/flexfiles can now use unprivileged ports when the generic NFS
    mount options allow it.
 
 Bugfixes:
  - Don't use RDMA direct data placement together with data integrity or
    privacy security flavours
  - Remove the RDMA ALLPHYSICAL memory registration mode as it has potential
    security holes.
  - Several layout recall fixes to improve NFSv4.1 protocol compliance.
  - Fix an Oops in the pNFS files and flexfiles connection setup to the DS
  - Allow retry of operations that used a returned delegation stateid
  - Don't mark the inode as revalidated if a LAYOUTCOMMIT is outstanding
  - Fix writeback races in nfs4_copy_range() and nfs42_proc_deallocate()
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Merge tag 'nfs-for-4.8-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs

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

  Stable bugfixes:
   - nfs: don't create zero-length requests

   - several LAYOUTGET bugfixes

  Features:
   - several performance related features

   - more aggressive caching when we can rely on close-to-open
     cache consistency

   - remove serialisation of O_DIRECT reads and writes

   - optimise several code paths to not flush to disk unnecessarily.

     However allow for the idiosyncracies of pNFS for those layout
     types that need to issue a LAYOUTCOMMIT before the metadata can
     be updated on the server.

   - SUNRPC updates to the client data receive path

   - pNFS/SCSI support RH/Fedora dm-mpath device nodes

   - pNFS files/flexfiles can now use unprivileged ports when
     the generic NFS mount options allow it.

  Bugfixes:
   - Don't use RDMA direct data placement together with data
     integrity or privacy security flavours

   - Remove the RDMA ALLPHYSICAL memory registration mode as
     it has potential security holes.

   - Several layout recall fixes to improve NFSv4.1 protocol
     compliance.

   - Fix an Oops in the pNFS files and flexfiles connection
     setup to the DS

   - Allow retry of operations that used a returned delegation
      stateid

   - Don't mark the inode as revalidated if a LAYOUTCOMMIT is
     outstanding

   - Fix writeback races in nfs4_copy_range() and
     nfs42_proc_deallocate()"

* tag 'nfs-for-4.8-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs: (104 commits)
  pNFS: Actively set attributes as invalid if LAYOUTCOMMIT is outstanding
  NFSv4: Clean up lookup of SECINFO_NO_NAME
  NFSv4.2: Fix warning "variable ‘stateids’ set but not used"
  NFSv4: Fix warning "no previous prototype for ‘nfs4_listxattr’"
  SUNRPC: Fix a compiler warning in fs/nfs/clnt.c
  pNFS: Remove redundant smp_mb() from pnfs_init_lseg()
  pNFS: Cleanup - do layout segment initialisation in one place
  pNFS: Remove redundant stateid invalidation
  pNFS: Remove redundant pnfs_mark_layout_returned_if_empty()
  pNFS: Clear the layout metadata if the server changed the layout stateid
  pNFS: Cleanup - don't open code pnfs_mark_layout_stateid_invalid()
  NFS: pnfs_mark_matching_lsegs_return() should match the layout sequence id
  pNFS: Do not set plh_return_seq for non-callback related layoutreturns
  pNFS: Ensure layoutreturn acts as a completion for layout callbacks
  pNFS: Fix CB_LAYOUTRECALL stateid verification
  pNFS: Always update the layout barrier seqid on LAYOUTGET
  pNFS: Always update the layout stateid if NFS_LAYOUT_INVALID_STID is set
  pNFS: Clear the layout return tracking on layout reinitialisation
  pNFS: LAYOUTRETURN should only update the stateid if the layout is valid
  nfs: don't create zero-length requests
  ...
2016-07-30 16:33:25 -07:00
Linus Torvalds 6784725ab0 Merge branch 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull vfs updates from Al Viro:
 "Assorted cleanups and fixes.

  Probably the most interesting part long-term is ->d_init() - that will
  have a bunch of followups in (at least) ceph and lustre, but we'll
  need to sort the barrier-related rules before it can get used for
  really non-trivial stuff.

  Another fun thing is the merge of ->d_iput() callers (dentry_iput()
  and dentry_unlink_inode()) and a bunch of ->d_compare() ones (all
  except the one in __d_lookup_lru())"

* 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (26 commits)
  fs/dcache.c: avoid soft-lockup in dput()
  vfs: new d_init method
  vfs: Update lookup_dcache() comment
  bdev: get rid of ->bd_inodes
  Remove last traces of ->sync_page
  new helper: d_same_name()
  dentry_cmp(): use lockless_dereference() instead of smp_read_barrier_depends()
  vfs: clean up documentation
  vfs: document ->d_real()
  vfs: merge .d_select_inode() into .d_real()
  unify dentry_iput() and dentry_unlink_inode()
  binfmt_misc: ->s_root is not going anywhere
  drop redundant ->owner initializations
  ufs: get rid of redundant checks
  orangefs: constify inode_operations
  missed comment updates from ->direct_IO() prototype change
  file_inode(f)->i_mapping is f->f_mapping
  trim fsnotify hooks a bit
  9p: new helper - v9fs_parent_fid()
  debugfs: ->d_parent is never NULL or negative
  ...
2016-07-28 12:59:05 -07:00
Trond Myklebust 362745268c Merge branch 'writeback' 2016-07-24 17:08:31 -04:00
Trond Myklebust f7b5c340ac NFS: Cleanup nfs_direct_complete()
There is only one caller that sets the "write" argument to true,
so just move the call to nfs_zap_mapping() and get rid of the
now redundant argument.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2016-07-05 19:11:04 -04:00
Trond Myklebust a5864c999d NFS: Do not serialise O_DIRECT reads and writes
Allow dio requests to be scheduled in parallel, but ensuring that they
do not conflict with buffered I/O.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2016-07-05 19:11:04 -04:00
Trond Myklebust 89698b24d2 NFS Cleanup: move call to generic_write_checks() into fs/nfs/direct.c
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2016-07-05 19:11:03 -04:00
Trond Myklebust 2f3c7d87a3 NFS: Remove racy size manipulations in O_DIRECT
On success, the RPC callbacks will ensure that we make the appropriate calls
to nfs_writeback_update_inode()

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2016-07-05 19:11:02 -04:00
Trond Myklebust a5314a7492 NFS: Ensure we reset the write verifier 'committed' value on resend.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2016-07-05 19:11:02 -04:00
Trond Myklebust 8fc3c38627 NFS: Fix O_DIRECT verifier problems
We should not be interested in looking at the value of the stable field,
since that could take any value.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2016-07-05 19:11:01 -04:00
Trond Myklebust d2a7de0b34 NFS: Fix up O_DIRECT results
if we read or wrote something, we must report it

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Reviewed-by: Jeff Layton <jlayton@poochiereds.net>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2016-06-24 12:01:00 -04:00
Al Viro 90090ae645 missed comment updates from ->direct_IO() prototype change
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-05-29 19:05:03 -04:00
Linus Torvalds ea8ea737c4 NFS client updates for Linux 4.7
Highlights include:
 
 Features:
 - Add support for the NFS v4.2 COPY operation
 - Add support for NFS/RDMA over IPv6
 
 Bugfixes and cleanups:
 - Avoid race that crashes nfs_init_commit()
 - Fix oops in callback path
 - Fix LOCK/OPEN race when unlinking an open file
 - Choose correct stateids when using delegations in setattr, read and write
 - Don't send empty SETATTR after OPEN_CREATE
 - xprtrdma: Prevent server from writing a reply into memory client has released
 - xprtrdma: Support using Read list and Reply chunk in one RPC call
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Merge tag 'nfs-for-4.7-1' of git://git.linux-nfs.org/projects/anna/linux-nfs

Pull NFS client updates from Anna Schumaker:
 "Highlights include:

  Features:
   - Add support for the NFS v4.2 COPY operation
   - Add support for NFS/RDMA over IPv6

  Bugfixes and cleanups:
   - Avoid race that crashes nfs_init_commit()
   - Fix oops in callback path
   - Fix LOCK/OPEN race when unlinking an open file
   - Choose correct stateids when using delegations in setattr, read and
     write
   - Don't send empty SETATTR after OPEN_CREATE
   - xprtrdma: Prevent server from writing a reply into memory client
     has released
   - xprtrdma: Support using Read list and Reply chunk in one RPC call"

* tag 'nfs-for-4.7-1' of git://git.linux-nfs.org/projects/anna/linux-nfs: (61 commits)
  pnfs: pnfs_update_layout needs to consider if strict iomode checking is on
  nfs/flexfiles: Use the layout segment for reading unless it a IOMODE_RW and reading is disabled
  nfs/flexfiles: Helper function to detect FF_FLAGS_NO_READ_IO
  nfs: avoid race that crashes nfs_init_commit
  NFS: checking for NULL instead of IS_ERR() in nfs_commit_file()
  pnfs: make pnfs_layout_process more robust
  pnfs: rework LAYOUTGET retry handling
  pnfs: lift retry logic from send_layoutget to pnfs_update_layout
  pnfs: fix bad error handling in send_layoutget
  flexfiles: add kerneldoc header to nfs4_ff_layout_prepare_ds
  flexfiles: remove pointless setting of NFS_LAYOUT_RETURN_REQUESTED
  pnfs: only tear down lsegs that precede seqid in LAYOUTRETURN args
  pnfs: keep track of the return sequence number in pnfs_layout_hdr
  pnfs: record sequence in pnfs_layout_segment when it's created
  pnfs: don't merge new ff lsegs with ones that have LAYOUTRETURN bit set
  pNFS/flexfiles: When initing reads or writes, we might have to retry connecting to DSes
  pNFS/flexfiles: When checking for available DSes, conditionally check for MDS io
  pNFS/flexfile: Fix erroneous fall back to read/write through the MDS
  NFS: Reclaim writes via writepage are opportunistic
  NFSv4: Use the right stateid for delegations in setattr, read and write
  ...
2016-05-26 10:33:33 -07:00