Pull nfsd updates from Bruce Fields:
"Highlights:
- support the NFSv4.2 SEEK operation (allowing clients to support
SEEK_HOLE/SEEK_DATA), thanks to Anna.
- end the grace period early in a number of cases, mitigating a
long-standing annoyance, thanks to Jeff
- improve SMP scalability, thanks to Trond"
* 'for-3.18' of git://linux-nfs.org/~bfields/linux: (55 commits)
nfsd: eliminate "to_delegation" define
NFSD: Implement SEEK
NFSD: Add generic v4.2 infrastructure
svcrdma: advertise the correct max payload
nfsd: introduce nfsd4_callback_ops
nfsd: split nfsd4_callback initialization and use
nfsd: introduce a generic nfsd4_cb
nfsd: remove nfsd4_callback.cb_op
nfsd: do not clear rpc_resp in nfsd4_cb_done_sequence
nfsd: fix nfsd4_cb_recall_done error handling
nfsd4: clarify how grace period ends
nfsd4: stop grace_time update at end of grace period
nfsd: skip subsequent UMH "create" operations after the first one for v4.0 clients
nfsd: set and test NFSD4_CLIENT_STABLE bit to reduce nfsdcltrack upcalls
nfsd: serialize nfsdcltrack upcalls for a particular client
nfsd: pass extra info in env vars to upcalls to allow for early grace period end
nfsd: add a v4_end_grace file to /proc/fs/nfsd
lockd: add a /proc/fs/lockd/nlm_end_grace file
nfsd: reject reclaim request when client has already sent RECLAIM_COMPLETE
nfsd: remove redundant boot_time parm from grace_done client tracking op
...
Commit 2f60ea6b8c ("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: Andy Adamson <andros@netapp.com>
Link: http://lkml.kernel.org/r/1411486536-23401-1-git-send-email-andros@netapp.com
Fixes: 2f60ea6b8c (NFSv4: The NFSv4.0 client must send RENEW calls...)
Cc: stable@vger.kernel.org # 3.2.x
Signed-off-by: Trond 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: Trond 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: Trond 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: James Pearson <james-p@moving-picture.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Steve Dickson <steved@redhat.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Silence a few warnings about missing symbols that are due to missing
includes of nfs3_fs.h.
Fixes: 00a36a1090 (NFS: Move v3 declarations out of internal.h)
Fixes: cb8c20fa53 (NFS: Move NFS v3 acl functions to nfs3_fs.h)
Signed-off-by: Trond 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: NeilBrown <neilb@suse.de>
Acked-by: Jeff Layton <jlayton@primarydata.com>
Signed-off-by: Trond 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: NeilBrown <neilb@suse.de>
Acked-by: Jeff Layton <jlayton@primarydata.com>
Signed-off-by: Trond 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: NeilBrown <neilb@suse.de>
Acked-by: Jeff Layton <jlayton@primarydata.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
commit b31268ac79
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: NeilBrown <neilb@suse.de>
Signed-off-by: Trond 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: NeilBrown <neilb@suse.de>
Signed-off-by: Trond 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: Olga Kornievskaia <kolga@netapp.com>
Fixes: c9fdeb280b (NFS: Add basic migration support to state manager thread)
Cc: stable@vger.kernel.org # 3.13+
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Commit 65b38851a1
("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: Fabian Frederick <fabf@skynet.be>
Fixes: 65b38851a1 (NFS: Fix /proc/fs/nfsfs/servers and...)
Cc: stable@vger.kernel.org # 3.4.x+
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
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: James Drews <drews@engr.wisc.edu>
Link: http://lkml.kernel.org/r/541AD7E5.8020409@engr.wisc.edu
Fixes: aee7af356e (NFSv4: Fix problems with close in the presence...)
Cc: stable@vger.kernel.org # 2.6.33+
Signed-off-by: Trond 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: Steve Dickson <steved@redhat.com>
Signed-off-by: Trond 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: Peng Tao <tao.peng@primarydata.com>
Signed-off-by: Trond 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: Anna Schumaker <Anna.Schumaker@Netapp.com>
Signed-off-by: Trond 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: Anna Schumaker <Anna.Schumaker@Netapp.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
I am generally against the "one big header file" approach, and
everything in the client includes this file. Let's move all the NFS v3
declarations into a v3-only header file.
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
The goal is to create a generic NFS module with code that does not
depend on what versions of NFS are enabled.
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
This code has been around for a while, but never was enabled, although
it is in a working shape.
Note that we implement NOTIFY_DEVICEID4_CHANGE identical to
NOTIFY_DEVICEID4_DELETE. Given that in either case we can't do anything
but preventing further lookups of a given device ID there isn't much difference
in semantics for the two. For the delete case the server MUST ensure that
there are no outstanding layouts, while for the change case it doesn't, but
that has little relevance to the client.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
This patches moves parsing of the GETDEVICEINFO XDR to kernel space, as well
as the management of complex devices. The reason for that is we might have
multiple outstanding complex devices after a NOTIFY_DEVICEID4_CHANGE, which
device mapper or md can't handle as they claim devices exclusively.
But as is turns out simple striping / concatenation is fairly trivial to
implement anyway, so we make our life simpler by reducing the reliance
on blkmapd. For now we still use blkmapd by feeding it synthetic SIMPLE
device XDR to translate device signatures to device numbers, but in the
long runs I have plans to eliminate it entirely.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Create a file to house all the rpc_pipefs boilerplate code instead of
sprinkling it over a few files.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Factor out a helper for all per-extent work, and merge the now trivial
functions for lseg allocation and parsing.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
This isn't device(id) related, so move it into the main file. Simple move
for now, the next commit will clean it up a bit.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Instead of overflowing the XDR send buffer with our extent list allocate
pages and pre-encode the layoutupdate payload into them. We optimistically
allocate a single page use alloc_page and only switch to vmalloc when we
have more extents outstanding. Currently there is only a single testcase
(xfstests generic/113) which can reproduce large enough extent lists for
this to occur.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
The current GETDEVICELIST implementation is buggy in that it doesn't handle
cursors correctly, and in that it returns an error if the server returns
NFSERR_NOTSUPP. Given that there is no actual need for GETDEVICELIST,
it has various issues and might get removed for NFSv4.2 stop using it in
the blocklayout driver, and thus the Linux NFS client as whole.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
The kbuild test robot complained about a new sparse warning in
objio_alloc_deviceid_node, but it turns out that this was just a moved
reference to an existing variable. Fix it to have the right big endian
annotated type.
Note that there are some other endianess issues in this file that I didn't
bother to sort out as they involve global headers.
Reported-by: kbuild test robot <fengguang.wu@intel.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
The kbuild test robot complained that we got the printk format wrong.
Let's just kill these printks instead of fixing them as there is not
point after the initial tree algorithm debugging.
Reported-by: kbuild test robot <fengguang.wu@intel.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
commit 4fa2c54b51
NFS: nfs4_do_open should add negative results to the dcache.
used "d_drop(); d_add();" to ensure that a dentry was hashed
as a negative cached entry.
This is not safe if the dentry has an non-NULL ->d_inode.
It will trigger a BUG_ON in d_instantiate().
In that case, d_delete() is needed.
Also, only d_add if the dentry is currently unhashed, it seems
pointless removed and re-adding it unchanged.
Reported-by: Christoph Hellwig <hch@infradead.org>
Fixes: 4fa2c54b51
Cc: Jeff Layton <jeff.layton@primarydata.com>
Link: http://lkml.kernel.org/r/20140908144525.GB19811@infradead.org
Signed-off-by: NeilBrown <neilb@suse.de>
Acked-by: Jeff Layton <jlayton@primarydata.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
sparse says:
fs/nfs/file.c:543:60: warning: incorrect type in argument 1 (different address spaces)
fs/nfs/file.c:543:60: expected struct rpc_xprt *xprt
fs/nfs/file.c:543:60: got struct rpc_xprt [noderef] <asn:4>*cl_xprt
fs/nfs/file.c:548:53: warning: incorrect type in argument 1 (different address spaces)
fs/nfs/file.c:548:53: expected struct rpc_xprt *xprt
fs/nfs/file.c:548:53: got struct rpc_xprt [noderef] <asn:4>*cl_xprt
cl_xprt is RCU-managed, so we need to take care to dereference and use
it while holding the RCU read lock.
Cc: Mel Gorman <mgorman@suse.de>
Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
The VFS never calls setattr with ATTR_SIZE on anything but regular
files. Remove the if check and turn it into an assert similar to
what some other file systems do.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
This will be used by the block layout driver when splitting extents.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
At a simple helper to issue a GETDEVICELIST operation and pre-load
the device id cache based on the result.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Add support to the common pNFS core to issue GETDEVICEINFO calls on
a device ID cache miss. The code is taken from the well debugged
file layout implementation and calls out to the layoutdriver through
a new alloc_deviceid_node method. The calling conventions for
nfs4_find_get_deviceid are changed so that all information needed to
send a GETDEVICEINFO request is passed to the common code.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
This speads up truncate-heavy workloads like fsx by multiple orders of
magnitude.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
This allows removing extents from the extent tree especially on truncate
operations, and thus fixing reads from truncated and re-extended that
previously returned stale data.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Currently the block layout driver tracks extents in three separate
data structures:
- the two list of pnfs_block_extent structures returned by the server
- the list of sectors that were in invalid state but have been written to
- a list of pnfs_block_short_extent structures for LAYOUTCOMMIT
All of these share the property that they are not only highly inefficient
data structures, but also that operations on them are even more inefficient
than nessecary.
In addition there are various implementation defects like:
- using an int to track sectors, causing corruption for large offsets
- incorrect normalization of page or block granularity ranges
- insufficient error handling
- incorrect synchronization as extents can be modified while they are in
use
This patch replace all three data with a single unified rbtree structure
tracking all extents, as well as their in-memory state, although we still
need to instance for read-only and read-write extent due to the arcane
client side COW feature in the block layouts spec.
To fix the problem of extent possibly being modified while in use we make
sure to return a copy of the extent for use in the write path - the
extent can only be invalidated by a layout recall or return which has
to wait until the I/O operations finished due to refcounts on the layout
segment.
The new extent tree work similar to the schemes used by block based
filesystems like XFS or ext4.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
The core nfs code handles setting pages uptodate on reads, no need to mess
with the pageflags outselves. Also remove a debug function to dump page
flags.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Use the new PNFS_READ_WHOLE_PAGE flag to offload read-modify-write
handling to core nfs code, and remove a huge chunk of deadlock prone
mess from the block layout writeback path.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
If a layout driver keeps per-inode state outside of the layout segments it
needs to be notified of any layout returns or recalls on an inode, and not
just about the freeing of layout segments. Add a method to acomplish this,
which will allow the block layout driver to handle the case of truncated
and re-expanded files properly.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Like all block based filesystems, the pNFS block layout driver can't read
or write at a byte granularity and thus has to perform read-modify-write
cycles on writes smaller than this granularity.
Add a flag so that the core NFS code always reads a whole page when
starting a smaller write, so that we can do it in the place where the VFS
expects it instead of doing in very deadlock prone way in the writeback
handler.
Note that in theory we could do less than page size reads here for disks
that have a smaller sector size which are served by a server with a smaller
pnfs block size. But so far that doesn't seem like a worthwhile
optimization.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Expedite layout recall processing by forcing a layout commit when
we see busy segments. Without it the layout recall might have to wait
until the VM decided to start writeback for the file, which can introduce
long delays.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
gcc reports:
linux/fs/nfs/write.c: In function ‘nfs_page_find_head_request_locked.isra.17’:
linux/fs/nfs/write.c:121:64: warning: ‘cinfo.mds’ may be used uninitialized in this function [-Wmaybe-uninitialized]
list_for_each_entry_safe(freq, t, &cinfo.mds->list, wb_list) {
^
linux/fs/nfs/write.c:110:25: note: ‘cinfo.mds’ was declared here
struct nfs_commit_info cinfo;
Reported-by: Anna Schumaker <Anna.Schumaker@netapp.com>
Cc: Weston Andros Adamson <dros@primarydata.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>