Commit Graph

224 Commits

Author SHA1 Message Date
Boaz Harrosh
2bea038c52 pnfs: write: Set mds_offset in the generic layer - it is needed by all LDs
In current pnfs tree, all the layouts set mds_offset in their
.write_pagelist member.
mds_offset is only used by generic layer and should be handled by it.

This patch is for upstream. It is needed in this -rc series to fix a
bug in objects layout_commit.

I'll send patches for objects and blocks to be
squashed into current pnfs tree.

TODO: It looks like the read path needs the same patch.

Signed-off-by: Boaz Harrosh <bharrosh@panasas.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2011-06-28 14:12:11 -04:00
Benny Halevy
dfed206b88 NFSv4.1: unify pnfs_pageio_init functions
Use common code for pnfs_pageio_init_{read,write} and use
a common generic pg_test function.

Note that this function always assumes the the layout driver's
pg_test method is implemented.

[Fix BUG]
Signed-off-by: Boaz Harrosh <bharrosh@panasas.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
2011-05-29 20:56:43 +03:00
Benny Halevy
fb3296eb46 pnfs: Use byte-range for layoutget
Add offset and count parameters to pnfs_update_layout and use them to get
the layout in the pageio path.

Order cache layout segments in the following order:
* offset (ascending)
* length (descending)
* iomode (RW before READ)

Test byte range against the layout segment in use in pnfs_{read,write}_pg_test
so not to coalesce pages not using the same layout segment.

[fix lseg ordering]
[clean up pnfs_find_lseg lseg arg]
[remove unnecessary FIXME]
[fix ordering in pnfs_insert_layout]
[clean up pnfs_insert_layout]
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
2011-05-29 20:52:32 +03:00
Trond Myklebust
a75b9df9d3 NFSv4.1: Ensure that layoutget uses the correct gfp modes
Currently, writebacks may end up recursing back into the filesystem due to
GFP_KERNEL direct reclaims in the pnfs subsystem.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2011-05-11 22:52:13 -04:00
Trond Myklebust
c0d0e96b84 NFS: Get rid of pointless test in nfs_commit_done
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2011-04-12 19:34:23 -04:00
Trond Myklebust
4b38a6db01 NFS: Eliminate duplicate call to nfs_mark_request_dirty
We only need to call nfs_mark_request_dirty() once in nfs_writepage_setup().

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2011-04-12 19:34:22 -04:00
Dave Chinner
0d88f6e804 nfs: don't call __mark_inode_dirty while holding i_lock
nfs_scan_commit() is called with the inode->i_lock held, but it then
calls __mark_inode_dirty() while still holding the lock. This causes
a deadlock.

Push the inode->i_lock into nfs_scan_commit() so it can protect only
the parts of the code it needs to and can be dropped before the call
to __mark_inode_dirty() to avoid the deadlock.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Tested-by: Will Simoneau <simoneau@ele.uri.edu>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-04-12 14:17:24 -07:00
Trond Myklebust
4d65c520fb NFS: Fix a hang in the writeback path
Now that the inode scalability patches have been merged, it is no longer
safe to call igrab() under the inode->i_lock.
Now that we no longer call nfs_clear_request() until the nfs_page is
being freed, we know that we are always holding a reference to the
nfs_open_context, which again holds a reference to the path, and so
the inode cannot be freed until the last nfs_page has been removed
from the radix tree and freed.

We can therefore skip the igrab()/iput() altogether.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2011-03-27 17:48:07 +02:00
Andy Adamson
ef31153786 NFSv4.1 convert layoutcommit sync to boolean
Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2011-03-24 15:49:48 -04:00
Andy Adamson
863a3c6c68 NFSv4.1: layoutcommit
The filelayout driver sends LAYOUTCOMMIT only when COMMIT goes to
the data server (as opposed to the MDS) and the data server WRITE
is not NFS_FILE_SYNC.

Only whole file layout support means that there is only one IOMODE_RW layout
segment.

Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Alexandros Batsakis <batsakis@netapp.com>
Signed-off-by: Boaz Harrosh <bharrosh@panasas.com>
Signed-off-by: Dean Hildebrand <dhildeb@us.ibm.com>
Signed-off-by: Fred Isaman <iisaman@citi.umich.edu>
Signed-off-by: Mingyang Guo <guomingyang@nrchpc.ac.cn>
Signed-off-by: Tao Guo <guotao@nrchpc.ac.cn>
Signed-off-by: Zhang Jingwang <zhangjingwang@nrchpc.ac.cn>
Tested-by: Boaz Harrosh <bharrosh@panasas.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
Signed-off-by: Fred Isaman <iisaman@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2011-03-23 15:29:04 -04:00
Fred Isaman
e0c2b38018 NFSv4.1: filelayout driver specific code for COMMIT
Implement all the hooks created in the previous patches.
This requires exporting quite a few functions and adding a few
structure fields.

Signed-off-by: Fred Isaman <iisaman@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2011-03-23 15:29:04 -04:00
Fred Isaman
988b6dceb0 NFSv4.1: remove GETATTR from ds commits
Any COMMIT compound directed to a data server needs to have the
GETATTR calls suppressed.  We here, make sure the field we are testing
(data->lseg) is set and refcounted correctly.

Signed-off-by: Fred Isaman <iisaman@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2011-03-23 15:29:03 -04:00
Fred Isaman
a861a1e1c3 NFSv4.1: add generic layer hooks for pnfs COMMIT
We create three major hooks for the pnfs code.

pnfs_mark_request_commit() is called during writeback_done from
nfs_mark_request_commit, which gives the driver an opportunity to
claim it wants control over commiting a particular req.

pnfs_choose_commit_list() is called from nfs_scan_list
to choose which list a given req should be added to, based on
where we intend to send it for COMMIT.  It is up to the driver
to have preallocated list headers for each destination it may need.

pnfs_commit_list() is how the driver actually takes control, it is
used instead of nfs_commit_list().

In order to pass information between the above functions, we create
a union in nfs_page to hold a lseg (which is possible because the req is
not on any list while in transition), and add some flags to indicate
if we need to use the pnfs code.

Signed-off-by: Fred Isaman <iisaman@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2011-03-23 15:29:03 -04:00
Fred Isaman
5917ce8440 NFSv4.1: pull out code from nfs_commit_release
Create a separate support function for later use by data server
commit code.

Signed-off-by: Fred Isaman <iisaman@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2011-03-23 15:29:03 -04:00
Fred Isaman
64bfeb49bd NFSv4.1: pull error handling out of nfs_commit_list
Create a separate support function for later use by data server
commit code.

Signed-off-by: Fred Isaman <iisaman@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2011-03-23 15:29:03 -04:00
Fred Isaman
9ace33cdc6 NFSv4.1: rearrange nfs_commit_rpcsetup
Reorder nfs_commit_rpcsetup, preparing for a pnfs entry point.

Signed-off-by: Fred Isaman <iisaman@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2011-03-23 15:29:02 -04:00
Fred Isaman
465d52437d NFSv4.1: don't send COMMIT to ds for data sync writes
Based on consensus reached in Feb 2011 interim IETF meeting regarding
use of LAYOUTCOMMIT, it has been decided that a NFS_DATA_SYNC return
from a WRITE to data server should not initiate a COMMIT.

Signed-off-by: Fred Isaman <iisaman@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2011-03-23 15:29:02 -04:00
Trond Myklebust
b8413f98f9 NFS: Fix a hang/infinite loop in nfs_wb_page()
When one of the two waits in nfs_commit_inode() is interrupted, it
returns a non-negative value, which causes nfs_wb_page() to think
that the operation was successful causing it to busy-loop rather
than exiting.
It also causes nfs_file_fsync() to incorrectly report the file as
being successfully committed to disk.

This patch fixes both problems by ensuring that we return an error
if the attempts to wait fail.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Cc: stable@kernel.org
2011-03-21 21:09:24 -04:00
Trond Myklebust
b31268ac79 FS: Use stable writes when not doing a bulk flush
If we're only doing a single write, and there are no other unstable
writes being queued up, we might want to just flip to using a stable
write RPC call.

Reviewed-by: NeilBrown <neilb@suse.de>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2011-03-21 21:08:17 -04:00
Fred Isaman
36fe432d33 NFSv4.1: Clear lseg pointer in ->doio function
Now that we have access to the pointer, clear it immediately after
the put, instead of in caller.

Signed-off-by: Fred Isaman <iisaman@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2011-03-11 15:38:45 -05:00
Fred Isaman
c76069bda0 NFSv4.1: rearrange ->doio args
This will make it possible to clear the lseg pointer in the same
function as it is put, instead of in the caller nfs_pageio_doio().

Signed-off-by: Fred Isaman <iisaman@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2011-03-11 15:38:44 -05:00
Fred Isaman
a69aef1496 NFSv4.1: pnfs filelayout driver write
Allows the pnfs filelayout driver to write to the data servers.

Note that COMMIT to data servers will be implemented in a future
patch.  To avoid improper behavior, for the moment any WRITE to a data
server that would also require a COMMIT to the data server is sent
NFS_FILE_SYNC.

Signed-off-by: Andy Adamson <andros@citi.umich.edu>
Signed-off-by: Dean Hildebrand <dhildeb@us.ibm.com>
Signed-off-by: Fred Isaman <iisaman@citi.umich.edu>
Signed-off-by: Mingyang Guo <guomingyang@nrchpc.ac.cn>
Signed-off-by: Oleg Drokin <green@linuxhacker.ru>
Signed-off-by: Ricardo Labiaga <Ricardo.Labiaga@netapp.com>
Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
Signed-off-by: Fred Isaman <iisaman@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2011-03-11 15:38:44 -05:00
Andy Adamson
0382b74409 NFSv4.1: implement generic pnfs layer write switch
Signed-off-by: Andy Adamson <andros@citi.umich.edu>
Signed-off-by: Boaz Harrosh <bharrosh@panasas.com>
Signed-off-by: Dean Hildebrand <dhildeb@us.ibm.com>
Signed-off-by: Fred Isaman <iisaman@citi.umich.edu>
Signed-off-by: J. Bruce Fields <bfields@fieldses.org>
Signed-off-by: Mike Sager <sager@netapp.com>
Signed-off-by: Ricardo Labiaga <Ricardo.Labiaga@netapp.com>
Signed-off-by: Tao Guo <guotao@nrchpc.ac.cn>
Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
Signed-off-by: Fred Isaman <iisaman@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2011-03-11 15:38:44 -05:00
Fred Isaman
44b83799a9 NFSv4.1: trigger LAYOUTGET for writes
Signed-off-by: Fred Isaman <iisaman@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2011-03-11 15:38:44 -05:00
Fred Isaman
5053aa568d NFSv4.1: Send lseg down into nfs_write_rpcsetup
We grab the lseg sent in from the doio function and attach it to
each struct nfs_write_data created.  This is how the lseg will be
sent to the layout driver.

Signed-off-by: Fred Isaman <iisaman@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2011-03-11 15:38:44 -05:00
Andy Adamson
d138d5d17b NFSv4.1: rearrange nfs_write_rpcsetup
Reorder nfs_write_rpcsetup, preparing for a pnfs entry point.

Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Fred Isaman <iisaman@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2011-03-11 15:38:43 -05:00
Fred Isaman
bae724ef95 NFSv4.1: shift pnfs_update_layout locations
Move the pnfs_update_layout call location to nfs_pageio_do_add_request().
Grab the lseg sent in the doio function to nfs_read_rpcsetup and attach
it to each nfs_read_data so it can be sent to the layout driver.

Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Andy Adamson <andros@citi.umich.edu>
Signed-off-by: Dean Hildebrand <dhildeb@us.ibm.com>
Signed-off-by: Fred Isaman <iisaman@citi.umich.edu>
Signed-off-by: Fred Isaman <iisaman@netapp.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
Signed-off-by: Boaz Harrosh <bharrosh@panasas.com>
Signed-off-by: Oleg Drokin <green@linuxhacker.ru>
Signed-off-by: Tao Guo <guotao@nrchpc.ac.cn>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2011-03-11 15:38:42 -05:00
Fred Isaman
94ad1c80e2 NFSv4.1: coelesce across layout stripes
Add a pg_test layout driver hook which is used to avoid coelescing I/O across
layout stripes.

Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Andy Adamson <andros@citi.umich.edu>
Signed-off-by: Dean Hildebrand <dhildeb@us.ibm.com>
Signed-off-by: Fred Isaman <iisaman@citi.umich.edu>
Signed-off-by: Fred Isaman <iisaman@netapp.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
Signed-off-by: Boaz Harrosh <bharrosh@panasas.com>
Signed-off-by: Oleg Drokin <green@linuxhacker.ru>
Signed-off-by: Tao Guo <guotao@nrchpc.ac.cn>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2011-03-11 15:38:42 -05:00
Fred Isaman
136028967a NFS: change nfs_writeback_done to return void
The return values are not used by any callers.

Signed-off-by: Fred Isaman <iisaman@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2011-03-11 15:38:40 -05:00
Jeff Layton
d2224e7afb nfs: close NFSv4 COMMIT vs. CLOSE race
I've been adding in more artificial delays in the NFSv4 commit and close
codepaths to uncover races. The kernel I'm testing has the patch to
close the race in __rpc_wait_for_completion_task that's in Trond's
cthon2011 branch. The reproducer I've been using does this in a loop:

	mkdir("DIR");
	fd = open("DIR/FILE", O_WRONLY|O_CREAT|O_EXCL, 0644);
	write(fd, "abcdefg", 7);
	close(fd);
	unlink("DIR/FILE");
	rmdir("DIR");

The above reproducer shouldn't result in any silly-renaming. However,
when I add a "msleep(100)" just after the nfs_commit_clear_lock call in
nfs_commit_release, I can almost always force one to occur. If I can
force it to occur with that, then it can happen without that delay
given the right timing.

nfs_commit_inode waits for the NFS_INO_COMMIT bit to clear when called
with FLUSH_SYNC set. nfs_commit_rpcsetup on the other hand does not wait
for the task to complete before putting its reference to it, so the last
reference get put in rpc_release task and gets queued to a workqueue.

In this situation, the last open context reference may be put by the
COMMIT release instead of the close() syscall. The close() syscall
returns too quickly and the unlink runs while the d_count is still
high since the COMMIT release hasn't put its dentry reference yet.

Fix this by having rpc_commit_rpcsetup wait for the RPC call to complete
before putting the task reference when FLUSH_SYNC is set. With this, the
last reference is put by the process that's initiating the FLUSH_SYNC
commit and the race is closed.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2011-03-10 15:04:53 -05:00
Fred Isaman
0da2a4ac33 NFS: fix handling of malloc failure during nfs_flush_multi()
Cleanup of the allocated list entries should not call
put_nfs_open_context() on each entry, as the context will
always be NULL, causing an oops.

Signed-off-by: Fred Isaman <iisaman@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2011-01-19 15:37:49 -05:00
Trond Myklebust
2df485a774 nfs: remove extraneous and problematic calls to nfs_clear_request
When a nfs_page is freed, nfs_free_request is called which also calls
nfs_clear_request to clean out the lock and open contexts and free the
pagecache page.

However, a couple of places in the nfs code call nfs_clear_request
themselves. What happens here if the refcount on the request is still high?
We'll be releasing contexts and freeing pointers while the request is
possibly still in use.

Remove those bare calls to nfs_clear_context. That should only be done when
the request is being freed.

Note that when doing this, we need to watch out for tests of req->wb_page.
Previously, nfs_set_page_tag_locked() and nfs_clear_page_tag_locked()
would check the value of req->wb_page to figure out if the page is mapped
into the nfsi->nfs_page_tree. We now indicate the page is mapped using
the new bit PG_MAPPED in req->wb_flags .

Reported-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2010-12-07 23:02:44 -05:00
Wu Fengguang
1b430beee5 writeback: remove nonblocking/encountered_congestion references
This removes more dead code that was somehow missed by commit 0d99519efe
(writeback: remove unused nonblocking and congestion checks).  There are
no behavior change except for the removal of two entries from one of the
ext4 tracing interface.

The nonblocking checks in ->writepages are no longer used because the
flusher now prefer to block on get_request_wait() than to skip inodes on
IO congestion.  The latter will lead to more seeky IO.

The nonblocking checks in ->writepage are no longer used because it's
redundant with the WB_SYNC_NONE check.

We no long set ->nonblocking in VM page out and page migration, because
a) it's effectively redundant with WB_SYNC_NONE in current code
b) it's old semantic of "Don't get stuck on request queues" is mis-behavior:
   that would skip some dirty inodes on congestion and page out others, which
   is unfair in terms of LRU age.

Inspired by Christoph Hellwig. Thanks!

Signed-off-by: Wu Fengguang <fengguang.wu@intel.com>
Cc: Theodore Ts'o <tytso@mit.edu>
Cc: David Howells <dhowells@redhat.com>
Cc: Sage Weil <sage@newdream.net>
Cc: Steve French <sfrench@samba.org>
Cc: Chris Mason <chris.mason@oracle.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-10-26 16:52:05 -07:00
Jeff Layton
a00dd6c03d NFS: don't use FLUSH_SYNC on WB_SYNC_NONE COMMIT calls (try #2)
WB_SYNC_NONE is supposed to mean "don't wait on anything". That should
also include not waiting for COMMIT calls to complete.

WB_SYNC_NONE is also implied when wbc->nonblocking and
wbc->for_background are set, so we can replace those checks in
nfs_commit_unstable_pages with a check for WB_SYNC_NONE.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Reviewed-by: Wu Fengguang <fengguang.wu@intel.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2010-09-29 14:42:30 -04:00
Benny Halevy
dfb4f30983 NFSv4.1: keep seq_res.sr_slot as pointer rather than an index
Having to explicitly initialize sr_slotid to NFS4_MAX_SLOT_TABLE
resulted in numerous bugs.  Keeping the current slot as a pointer
to the slot table is more straight forward and robust as it's
implicitly set up to NULL wherever the seq_res member is initialized
to zeroes.

Signed-off-by: Benny Halevy <bhalevy@panasas.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2010-09-24 09:17:01 -04:00
Linus Torvalds
5df6b8e65a Merge branch 'nfs-for-2.6.36' of git://git.linux-nfs.org/projects/trondmy/nfs-2.6
* 'nfs-for-2.6.36' of git://git.linux-nfs.org/projects/trondmy/nfs-2.6: (42 commits)
  NFS: NFSv4.1 is no longer a "developer only" feature
  NFS: NFS_V4 is no longer an EXPERIMENTAL feature
  NFS: Fix /proc/mount for legacy binary interface
  NFS: Fix the locking in nfs4_callback_getattr
  SUNRPC: Defer deleting the security context until gss_do_free_ctx()
  SUNRPC: prevent task_cleanup running on freed xprt
  SUNRPC: Reduce asynchronous RPC task stack usage
  SUNRPC: Move the bound cred to struct rpc_rqst
  SUNRPC: Clean up of rpc_bindcred()
  SUNRPC: Move remaining RPC client related task initialisation into clnt.c
  SUNRPC: Ensure that rpc_exit() always wakes up a sleeping task
  SUNRPC: Make the credential cache hashtable size configurable
  SUNRPC: Store the hashtable size in struct rpc_cred_cache
  NFS: Ensure the AUTH_UNIX credcache is allocated dynamically
  NFS: Fix the NFS users of rpc_restart_call()
  SUNRPC: The function rpc_restart_call() should return success/failure
  NFSv4: Get rid of the bogus RPC_ASSASSINATED(task) checks
  NFSv4: Clean up the process of renewing the NFSv4 lease
  NFSv4.1: Handle NFS4ERR_DELAY on SEQUENCE correctly
  NFS: nfs_rename() should not have to flush out writebacks
  ...
2010-08-07 13:19:36 -07:00
Trond Myklebust
77a63f3d1e NFS: Fix a typo in include/linux/nfs_fs.h
nfs_commit_inode() needs to be defined irrespectively of whether or not
we are supporting NFSv3 and NFSv4.

Allow the compiler to optimise away code in the NFSv2-only case by
converting it into an inlined stub function.

Reported-and-tested-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-08-01 15:10:01 -07:00
Trond Myklebust
cfb506e1d3 NFS: Ensure that writepage respects the nonblock flag
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2010-07-30 15:38:56 -04:00
Trond Myklebust
b608b283a9 NFS: kswapd must not block in nfs_release_page
See https://bugzilla.kernel.org/show_bug.cgi?id=16056

If other processes are blocked waiting for kswapd to free up some memory so
that they can make progress, then we cannot allow kswapd to block on those
processes.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Cc: stable@kernel.org
2010-07-30 15:38:42 -04:00
Trond Myklebust
f11ac8db5d NFSv4: Ensure that we track the NFSv4 lock state in read/write requests.
This patch fixes bugzilla entry 14501:
  https://bugzilla.kernel.org/show_bug.cgi?id=14501

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2010-07-30 14:41:56 -04:00
Trond Myklebust
035168ab39 NFSv4.1: Make nfs4_setup_sequence take a nfs_server argument
In anticipation of the day when we have per-filesystem sessions, and also
in order to allow the session to change in the event of a filesystem
migration event.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2010-06-22 13:24:02 -04:00
Trond Myklebust
0522f6aded NFS: Fix another nfs_wb_page() deadlock
J.R. Okajima reports that the call to sync_inode() in nfs_wb_page() can
deadlock with other writeback flush calls. It boils down to the fact
that we cannot ever call writeback_single_inode() while holding a page
lock (even if we do set nr_to_write to zero) since another process may
already be waiting in the call to do_writepages(), and so will deny us
the I_SYNC lock.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2010-05-26 08:43:53 -04:00
Trond Myklebust
c5efa5fc91 NFS: Ensure that we mark the inode as dirty if we exit early from commit
If we exit from nfs_commit_inode() without ensuring that the COMMIT rpc
call has been completed, we must re-mark the inode as dirty. Otherwise,
future calls to sync_inode() with the WB_SYNC_ALL flag set will fail to
ensure that the data is on the disk.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2010-05-26 08:43:52 -04:00
Trond Myklebust
ba8b06e67e NFS: Ensure that nfs_wb_page() waits for Pg_writeback to clear
Neil Brown reports that he is seeing the BUG_ON(ret == 0) trigger in
nfs_page_async_flush. According to the trace in
     https://bugzilla.novell.com/show_bug.cgi?id=599628
the problem appears to be due to nfs_wb_page() not waiting for the
PG_writeback flag to clear.

There is a ditto problem in nfs_wb_page_cancel()

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2010-04-27 18:33:54 -04:00
Trond Myklebust
71d0a6112a NFS: Fix an unstable write data integrity race
Commit 2c61be0a94 (NFS: Ensure that the WRITE
and COMMIT RPC calls are always uninterruptible) exposed a race on file
close. In order to ensure correct close-to-open behaviour, we want to wait
for all outstanding background commit operations to complete.

This patch adds an inode flag that indicates if a commit operation is under
way, and provides a mechanism to allow ->write_inode() to wait for its
completion if this is a data integrity flush.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2010-04-22 15:35:57 -04:00
Trond Myklebust
2c61be0a94 NFS: Ensure that the WRITE and COMMIT RPC calls are always uninterruptible
We always want to ensure that WRITE and COMMIT completes, whether or not
the user presses ^C. Do this by making the call asynchronous, and allowing
the user to do an interruptible wait for rpc_task completion.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2010-04-09 19:54:50 -04:00
Trond Myklebust
a6305ddb08 NFS: Fix a race with the new commit code
This patch fixes a race which occurs due to the fact that we release the
PG_writeback flag while still holding the nfs_page locked.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2010-04-09 19:08:17 -04:00
Trond Myklebust
b80c3cb628 NFS: Ensure that writeback_single_inode() calls write_inode() when syncing
Since writeback_single_inode() checks the inode->i_state flags _before_ it
flushes out the data, we need to ensure that the I_DIRTY_DATASYNC flag is
already set. Otherwise we risk not seeing a call to write_inode(), which
again means that we break fsync() et al...

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2010-04-09 19:08:17 -04:00
Trond Myklebust
7f2f12d963 NFS: Simplify nfs_wb_page()
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2010-03-05 15:44:55 -05:00
Trond Myklebust
acdc53b214 NFS: Replace __nfs_write_mapping with sync_inode()
Now that we have correct COMMIT semantics in writeback_single_inode, we can
reduce and simplify nfs_wb_all(). Also replace nfs_wb_nocommit() with a
call to filemap_write_and_wait(), which doesn't need to hold the
inode->i_mutex.

With that done, we can eliminate nfs_write_mapping() altogether.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2010-03-05 15:44:55 -05:00