Commit graph

253 commits

Author SHA1 Message Date
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
Trond Myklebust
c988950eb6 NFS: Simplify nfs_wb_page_cancel()
In all cases we should be able to just remove the request and call
cancel_dirty_page().

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2010-03-05 15:44:55 -05:00
Trond Myklebust
2928db1ffe NFS: Ensure inode is always marked I_DIRTY_DATASYNC, if it has unstable pages
Since nfs_scan_list() doesn't wait for locked pages, we have a race in
which it is possible to end up with an inode that needs to send a COMMIT,
but which does not have the I_DIRTY_DATASYNC flag set.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2010-03-05 15:44:54 -05:00
Trond Myklebust
5bad5abec4 NFS: Run COMMIT as an asynchronous RPC call when wbc->for_background is set
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Acked-by: Wu Fengguang <fengguang.wu@intel.com>
2010-03-05 15:44:54 -05:00
Trond Myklebust
420e3646bb NFS: Reduce the number of unnecessary COMMIT calls
If the caller is doing a non-blocking flush, and there are still writebacks
pending on the wire, we can usually defer the COMMIT call until those
writes are done.

Also ensure that we honour the wbc->nonblocking flag.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2010-03-05 15:44:54 -05:00
Trond Myklebust
ff778d02bf NFS: Add a count of the number of unstable writes carried by an inode
In order to know when we should do opportunistic commits of the unstable
writes, when the VM is doing a background flush, we add a field to count
the number of unstable writes.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2010-03-05 15:44:54 -05:00
Trond Myklebust
8fc795f703 NFS: Cleanup - move nfs_write_inode() into fs/nfs/write.c
The sole purpose of nfs_write_inode is to commit unstable writes, so
move it into fs/nfs/write.c, and make nfs_commit_inode static.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2010-03-05 15:44:53 -05:00
Trond Myklebust
7549ad5f9b NFS: Remove a redundant check for PageFsCache in nfs_migrate_page()
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Acked-by: David Howells <dhowells@redhat.com>
2010-02-09 14:29:21 -05:00
H Hartley Sweeten
0aa05887af NFS: Make nfs_commitdata_release static
The symbol nfs_commitdata_release is only used locally
in this file. Make it static to prevent the following sparse warning:

warning: symbol 'nfs_commitdata_release' was not declared. Should it be static?

Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Cc: Trond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Reviewed-by: Chuck Lever <chuck.lever@oracle.com>
2010-01-26 15:42:03 -05:00
Trond Myklebust
c9edda7140 NFS: Fix a reference leak in nfs_wb_cancel_page()
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Cc: stable@kernel.org
Reviewed-by: Chuck Lever <chuck.lever@oracle.com>
2010-01-26 15:41:34 -05:00
Trond Myklebust
52c9948b1f Merge branch 'nfs-for-2.6.33' 2009-12-13 13:56:27 -05:00
Trond Myklebust
190f38e5ce NFS: Fix nfs_migrate_page()
The call to migrate_page() will cause the page->private field to be
cleared.
Also fix up the locking around the page->private transfer, so that we ensure
that calls to nfs_page_find_request() don't end up racing.

Finally, fix up a double free bug: nfs_unlock_request() already calls
nfs_release_request() for us...

Reported-by: Wu Fengguang <fengguang.wu@intel.com>
Tested-by: Andi Kleen <andi@firstfloor.org>
Cc: stable@kernel.org
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2009-12-10 09:05:55 -05:00
Christoph Hellwig
6b2f3d1f76 vfs: Implement proper O_SYNC semantics
While Linux provided an O_SYNC flag basically since day 1, it took until
Linux 2.4.0-test12pre2 to actually get it implemented for filesystems,
since that day we had generic_osync_around with only minor changes and the
great "For now, when the user asks for O_SYNC, we'll actually give
O_DSYNC" comment.  This patch intends to actually give us real O_SYNC
semantics in addition to the O_DSYNC semantics.  After Jan's O_SYNC
patches which are required before this patch it's actually surprisingly
simple, we just need to figure out when to set the datasync flag to
vfs_fsync_range and when not.

This patch renames the existing O_SYNC flag to O_DSYNC while keeping it's
numerical value to keep binary compatibility, and adds a new real O_SYNC
flag.  To guarantee backwards compatiblity it is defined as expanding to
both the O_DSYNC and the new additional binary flag (__O_SYNC) to make
sure we are backwards-compatible when compiled against the new headers.

This also means that all places that don't care about the differences can
just check O_DSYNC and get the right behaviour for O_SYNC, too - only
places that actuall care need to check __O_SYNC in addition.  Drivers and
network filesystems have been updated in a fail safe way to always do the
full sync magic if O_DSYNC is set.  The few places setting O_SYNC for
lower layers are kept that way for now to stay failsafe.

We enforce that O_DSYNC is set when __O_SYNC is set early in the open path
to make sure we always get these sane options.

Note that parisc really screwed up their headers as they already define a
O_DSYNC that has always been a no-op.  We try to repair it by using it for
the new O_DSYNC and redefinining O_SYNC to send both the traditional
O_SYNC numerical value _and_ the O_DSYNC one.

Cc: Richard Henderson <rth@twiddle.net>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Grant Grundler <grundler@parisc-linux.org>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Andreas Dilger <adilger@sun.com>
Acked-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Acked-by: Kyle McMartin <kyle@mcmartin.ca>
Acked-by: Ulrich Drepper <drepper@redhat.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Jan Kara <jack@suse.cz>
2009-12-10 15:02:50 +01:00
Trond Myklebust
0110ee152b NFS: Fix up the declaration of nfs4_restart_rpc when NFSv4 not configured
Also rename it: it is used in generic code, and so should not have a 'nfs4'
prefix.

Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2009-12-07 09:00:24 -05:00
Trond Myklebust
d61e612a72 NFSv41: Clean up slot table management
We no longer need to maintain a distinction between nfs41_sequence_done and
nfs41_sequence_free_slot.

This fixes a number of slot table leakages in the NFSv4.1 code.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2009-12-05 19:32:19 -05:00
Andy Adamson
e608e79f1b nfs41: call free slot from nfs4_restart_rpc
nfs41_sequence_free_slot can be called multiple times on SEQUENCE operation
errors.
No reason to inline nfs4_restart_rpc

Reported-by: Trond Myklebust <trond.myklebust@netapp.com>

nfs_writeback_done and nfs_readpage_retry call nfs4_restart_rpc outside the
error handler, and the slot is not freed prior to restarting in the rpc_prepare
state during session reset.

Fix this by moving the call to nfs41_sequence_free_slot from the error
path of nfs41_sequence_done into nfs4_restart_rpc, and by removing the test
for NFS4CLNT_SESSION_SETUP.
Always free slot and goto the rpc prepare state on async errors.

Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2009-12-04 15:55:29 -05:00
Wu Fengguang
b17621fed6 writeback: introduce wbc.for_background
It will lower the flush priority for NFS, and maybe more in future.

Signed-off-by: Wu Fengguang <fengguang.wu@intel.com>
Cc: Trond Myklebust <Trond.Myklebust@netapp.com>
Cc: Jens Axboe <jens.axboe@oracle.com>
Cc: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2009-12-03 13:54:25 +01:00
Jens Axboe
1fe06ad892 writeback: get rid of wbc->for_writepages
It's only set, it's never checked. Kill it.

Acked-by: Jan Kara <jack@suse.cz>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2009-09-16 15:16:18 +02:00
Trond Myklebust
6a396f67d2 Merge branch 'nfsv4_xdr_cleanups-for-2.6.32' into nfs-for-2.6.32
Conflicts:
	fs/nfs/nfs4xdr.c
2009-08-19 18:21:52 -04:00
Trond Myklebust
1ae88b2e44 NFS: Fix an O_DIRECT Oops...
We can't call nfs_readdata_release()/nfs_writedata_release() without
first initialising and referencing args.context. Doing so inside
nfs_direct_read_schedule_segment()/nfs_direct_write_schedule_segment()
causes an Oops.

We should rather be calling nfs_readdata_free()/nfs_writedata_free() in
those cases.

Looking at the O_DIRECT code, the "struct nfs_direct_req" is already
referencing the nfs_open_context for us. Since the readdata and writedata
structures carry a reference to that, we can simplify things by getting rid
of the extra nfs_open_context references, so that we can replace all
instances of nfs_readdata_release()/nfs_writedata_release().

Reported-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Tested-by: Catalin Marinas <catalin.marinas@arm.com>
Cc: stable@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-08-12 08:21:39 -07:00
Trond Myklebust
074cc1deec NFS: Add a ->migratepage() aop for NFS
Make NFS a bit more friendly to NUMA and memory hot removal...

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2009-08-10 08:54:13 -04:00
Linus Torvalds
81e4e1ba7e Revert "fuse: Fix build error" as unnecessary
This reverts commit 097041e576.

Trond had a better fix, which is the parent of this one ("Fix compile
error due to congestion_wait() changes")

Requested-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Acked-by: Larry Finger <Larry.Finger@lwfinger.net>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-07-11 11:22:34 -07:00
Larry Finger
097041e576 fuse: Fix build error
When building v2.6.31-rc2-344-g69ca06c, the following build errors are
found due to missing includes:

 CC [M]  fs/fuse/dev.o
fs/fuse/dev.c: In function ‘request_end’:
fs/fuse/dev.c:289: error: ‘BLK_RW_SYNC’ undeclared (first use in this function)
...
fs/nfs/write.c: In function ‘nfs_set_page_writeback’:
fs/nfs/write.c:207: error: ‘BLK_RW_ASYNC’ undeclared (first use in this function)

Signed-off-by: Larry Finger@lwfinger.net>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-07-10 19:09:46 -07:00
Jens Axboe
8aa7e847d8 Fix congestion_wait() sync/async vs read/write confusion
Commit 1faa16d228 accidentally broke
the bdi congestion wait queue logic, causing us to wait on congestion
for WRITE (== 1) when we really wanted BLK_RW_ASYNC (== 0) instead.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2009-07-10 20:31:53 +02:00
Andy Adamson
eedc020e71 nfs41: use rpc prepare call state for session reset
[nfs41: change nfs4_restart_rpc argument]
[nfs41: check for session not minorversion]
[nfs41: trigger the state manager for session reset]
Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
[always define nfs4_restart_rpc]
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2009-06-17 12:25:07 -07:00
Andy Adamson
21d9a851aa nfs41 commit sequence setup done support
Separate commit calls from nfs41: sequence setup/done support

Implement the commit rpc_call_prepare method for
asynchronuos nfs rpcs, call nfs41_setup_sequence from
respective rpc_call_validate_args methods.

Call nfs4_sequence_done from respective rpc_call_done methods.

Note that we need to pass a pointer to the nfs_server in calls data
for passing on to nfs4_sequence_done.

Signed-off-by: Andy Adamson<andros@netapp.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
[pnfs: client data server write validate and release]
Signed-off-by: Andy Adamson<andros@umich.edu>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
[nfs41: Support sessions with O_DIRECT.]
Signed-off-by: Dean Hildebrand <dhildeb@us.ibm.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
[nfs41: separate free slot from sequence done]
[nfs41: nfs4_sequence_free_slot use nfs_client for data server]
Signed-off-by: Andy Adamson<andros@umich.edu>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2009-06-17 10:46:50 -07:00
Andy Adamson
def6ed7ef4 nfs41 write sequence setup done support
Separate write calls from nfs41: sequence setup/done support

Implement the write rpc_call_prepare method for
asynchronuos nfs rpcs, call nfs41_setup_sequence from
respective rpc_call_validate_args methods.

Call nfs4_sequence_done from respective rpc_call_done methods.

Note that we need to pass a pointer to the nfs_server in calls data
for passing on to nfs4_sequence_done.

Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
[pnfs: client data server write validate and release]
Signed-off-by: Andy Adamson <andros@umich.edu>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
[move the nfs4_sequence_free_slot call in nfs_readpage_retry from]
[nfs41: separate free slot from sequence done
Signed-off-by: Andy Adamson <andros@umich.edu>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
[nfs41: Support sessions with O_DIRECT.]
Signed-off-by: Dean Hildebrand <dhildeb@us.ibm.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
[nfs41: nfs4_sequence_free_slot use nfs_client for data server]
Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2009-06-17 10:46:49 -07:00
Andy Adamson
5f7dbd5c75 nfs41: set up seq_res.sr_slotid
Initialize nfs4_sequence_res sr_slotid to NFS4_MAX_SLOT_TABLE.

[was nfs41: sequence res use slotid]
Signed-off-by: Andy Adamson <andros@netapp.com>
[pulled definition of struct nfs4_sequence_res.sr_slotid to here]
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2009-06-17 10:46:30 -07:00
Trond Myklebust
47c6256420 NFS: Fix up a mismerged patch
Move the definition of nfs_need_commit() into the #ifdef CONFIG_NFS_V3
section as originally intended in the patch "NFS: cleanup - remove
struct nfs_inode->ncommit"

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2009-03-19 15:17:40 -04:00
Trond Myklebust
72cb77f4a5 NFS: Throttle page dirtying while we're flushing to disk
The following patch is a combination of a patch by myself and Peter
Staubach.

Trond: If we allow other processes to dirty pages while a process is doing
a consistency sync to disk, we can end up never making progress.

Peter: Attached is a patch which addresses a continuing problem with
the NFS client generating out of order WRITE requests.  While
this is compliant with all of the current protocol
specifications, there are servers in the market which can not
handle out of order WRITE requests very well.  Also, this may
lead to sub-optimal block allocations in the underlying file
system on the server.  This may cause the read throughputs to
be reduced when reading the file from the server.

Peter: There has been a lot of work recently done to address out of
order issues on a systemic level.  However, the NFS client is
still susceptible to the problem.  Out of order WRITE
requests can occur when pdflush is in the middle of writing
out pages while the process dirtying the pages calls
generic_file_buffered_write which calls
generic_perform_write which calls
balance_dirty_pages_rate_limited which ends up calling
writeback_inodes which ends up calling back into the NFS
client to writes out dirty pages for the same file that
pdflush happens to be working with.

Signed-off-by: Peter Staubach <staubach@redhat.com>
[modification by Trond to merge the two similar patches]
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2009-03-11 14:10:30 -04:00
Trond Myklebust
fb8a1f11b6 NFS: cleanup - remove struct nfs_inode->ncommit
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2009-03-11 14:10:29 -04:00
Trond Myklebust
d7fb120774 NFS: Don't use range_cyclic for data integrity syncs
It is more efficient to write linearly starting from the beginning of the
file.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-10-07 18:19:05 -04:00
Trond Myklebust
a3d01454bc NFS: Remove BKL requirement from attribute updates
The main problem is dealing with inode->i_size: we need to set the
inode->i_lock on all attribute updates, and so vmtruncate won't cut it.
Make an NFS-private version of vmtruncate that has the necessary locking
semantics.

The result should be that the following inode attribute updates are
protected by inode->i_lock
	nfsi->cache_validity
	nfsi->read_cache_jiffies
	nfsi->attrtimeo
	nfsi->attrtimeo_timestamp
	nfsi->change_attr
	nfsi->last_updated
	nfsi->cache_change_attribute
	nfsi->access_cache
	nfsi->access_cache_entry_lru
	nfsi->access_cache_inode_lru
	nfsi->acl_access
	nfsi->acl_default
	nfsi->nfs_page_tree
	nfsi->ncommit
	nfsi->npages
	nfsi->open_files
	nfsi->silly_list
	nfsi->acl
	nfsi->open_states
	inode->i_size
	inode->i_atime
	inode->i_mtime
	inode->i_ctime
	inode->i_nlink
	inode->i_uid
	inode->i_gid

The following is protected by dir->i_mutex
	nfsi->cookieverf

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-07-15 18:10:51 -04:00
Trond Myklebust
e468bae97d NFS: Allow redirtying of a completed unstable write.
Currently, if an unstable write completes, we cannot redirty the page in
order to reflect a new change in the page data until after we've sent a
COMMIT request.

This patch allows a page rewrite to proceed without the unnecessary COMMIT
step, putting it immediately back onto the dirty page list, undoing the
VM unstable write accounting, and removing the NFS_PAGE_TAG_COMMIT tag from
the NFS radix tree.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-07-09 12:09:24 -04:00
Trond Myklebust
e7d39069e3 NFS: Clean up nfs_update_request()
Simplify the loop in nfs_update_request by moving into a separate function
the code that attempts to update an existing cached NFS write.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-07-09 12:09:23 -04:00
Chuck Lever
48186c7d57 NFS: Fix trace debugging nits in write.c
Clean up: fix a few dprintk messages that still need to show the RPC task ID
correctly, and be sure we use the preferred %lld or %llu instead of %Ld or
%Lu.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-07-09 12:09:05 -04:00
Trond Myklebust
7e5f614660 NFS: Revert commit 44dd151d
Revert commit 44dd151d "NFS: Don't mark a written page as uptodate until it
is on disk". While it is true that the write may fail, that is always the
case. There is no reason why we should treat data on pages that are not
already marked as PG_uptodate as being special. The only thing we gain is a
noticeable slowdown when re-reading these pages.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-07-09 12:08:46 -04:00
Trond Myklebust
efc91ed019 NFS: Optimise append writes with holes
If a file is being extended, and we're creating a hole, we might as well
declare the entire page to be up to date.

This patch significantly improves the write performance for sparse files
in the case where lseek(SEEK_END) is used to append several non-contiguous
writes at intervals of < PAGE_SIZE.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-07-09 12:08:45 -04:00
Trond Myklebust
f3d47a3a6a NFS: Fix a preemption count leak in nfs_update_request
The commit 2785259631 (nfs: use GFP_NOFS
preloads for radix-tree insertion) appears to have introduced a bug:
We only want to call radix_tree_preload() once after creating a request.
Calling it every time we loop after we created the request, will cause
preemption count leaks.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Cc: Nick Piggin <npiggin@suse.de>
2008-07-09 12:08:39 -04:00
Trond Myklebust
03fa9e84e5 NFS: nfs_updatepage(): don't mark page as dirty if an error occurred
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-06-23 17:09:07 -04:00
Fred Isaman
38def50fab nfs: fix race in nfs_dirty_request
When called from nfs_flush_incompatible, the req is not locked, so
req->wb_page might be set to NULL before it is used by PageWriteback.

Signed-off-by: Fred Isaman <iisaman@citi.umich.edu>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-05-16 09:43:23 -07:00
Trond Myklebust
dbae4c73f0 NFS: Ensure that rpc_run_task() errors are propagated back to the caller
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-04-19 16:53:08 -04:00
Trond Myklebust
c9d8f89d98 NFS: Ensure that the write code cleans up properly when rpc_run_task() fails
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-04-19 16:53:05 -04:00
Trond Myklebust
73e3302f60 NFS: Fix nfs_wb_page() to always exit with an error or a clean page
It is possible for nfs_wb_page() to sometimes exit with 0 return value, yet
the page is left in a dirty state.
For instance in the case where the server rebooted, and the COMMIT request
failed, then all the previously "clean" pages which were cached by the
server, but were not guaranteed to have been writted out to disk,
have to be redirtied and resent to the server.
The fix is to have nfs_wb_page_priority() check that the page is clean
before it exits...

This fixes a condition that triggers the BUG_ON(PagePrivate(page)) in
nfs_create_request() when we're in the nfs_readpage() path.

Also eliminate a redundant BUG_ON(!PageLocked(page)) while we're at it. It
turns out that clear_page_dirty_for_io() has the exact same test.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-04-19 16:52:58 -04:00
Fred
6d884e8fc8 nfs: nfs_redirty_request
Both flush functions have the same error handling routine.  Pull
it out as a function.

Signed-off-by: Fred Isaman <iisaman@citi.umich.edu>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-03-19 17:59:56 -04:00
Trond Myklebust
c7c350e92a Merge branch 'hotfixes' into devel 2008-03-19 17:59:44 -04:00
Fred Isaman
f8512ad0da nfs: don't ignore return value from nfs_pageio_add_request
Ignoring the return value from nfs_pageio_add_request can cause deadlocks.

In read path:
  call nfs_pageio_add_request from readpage_async_filler
  assume at this point that there are requests already in desc, that
    can't be merged with the current request.
  so nfs_pageio_doio is fired up to clear out desc.
  assume something goes wrong in setting up the io, so desc->pg_error is set.
  This causes nfs_pageio_add_request to return 0, *WITHOUT* adding the original
    request.
  BUT, since return code is ignored, readpage_async_filler assumes it has
    been added, and does nothing further, leaving page locked.
  do_generic_mapping_read will eventually call lock_page, resulting in deadlock

In write path:
  page is marked dirty by generic_perform_write
  nfs_writepages is called
  call nfs_pageio_add_request from nfs_page_async_flush
  assume at this point that there are requests already in desc, that
    can't be merged with the current request.
  so nfs_pageio_doio is fired up to clear out desc.
  assume something goes wrong in setting up the io, so desc->pg_error is set.
  This causes nfs_page_async_flush to return 0, *WITHOUT* adding the original
    request, yet marking the request as locked (PG_BUSY) and in writeback,
    clearing dirty marks.
  The next time a write is done to the page, deadlock will result as
    nfs_write_end calls nfs_update_request

Signed-off-by: Fred Isaman <iisaman@citi.umich.edu>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-03-19 17:59:02 -04:00
Trond Myklebust
af1b8c2ff7 NFS: Fix an f_mode/f_flags confusion in fs/nfs/write.c
O_SYNC is stored in filp->f_flags.
Thanks to Al Viro for pointing out the bug.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-03-07 14:33:40 -05:00
Trond Myklebust
cdd0972945 Merge branch 'cleanups' into next 2008-02-28 23:48:05 -08:00
Trond Myklebust
5e4424af9a SUNRPC: Remove now-redundant RCU-safe rpc_task free path
Now that we've tightened up the locking rules for RPC queue wakeups, we can
remove the RCU-safe kfree calls...

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-02-28 23:26:28 -08:00
Trond Myklebust
101070ca2f NFS: Ensure that the asynchronous RPC calls complete on nfsiod.
We want to ensure that rpc_call_ops that involve mntput() are run on nfsiod
rather than on rpciod, so that they don't deadlock when the resulting
umount calls rpc_shutdown_client(). Hence we specify that read, write and
commit calls must complete on nfsiod.
Ditto for NFSv4 open, lock, locku and close asynchronous calls.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-02-25 21:40:37 -08:00
Trond Myklebust
383ba71938 NFS: Fix a deadlock with lazy umount
We can't allow rpc callback functions like task->tk_ops->rpc_call_prepare()
and task->tk_ops->rpc_call_done() to call mntput() in any way, since
that will cause a deadlock when the call to rpc_shutdown_client() attempts
to wait on 'task' to complete.

We can avoid the above deadlock by moving calls to mntput to
task->tk_ops->rpc_release() callback, since at that time the task will be
marked as completed, and so rpc_shutdown_client won't attempt to wait on
it.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-02-25 21:40:33 -08:00
Trond Myklebust
4b5621f6b1 NFS: Fix an f_mode/f_flags confusion in fs/nfs/write.c
O_SYNC is stored in filp->f_flags.
Thanks to Al Viro for pointing out the bug.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-02-25 15:56:29 -08:00
Nick Piggin
2785259631 nfs: use GFP_NOFS preloads for radix-tree insertion
NFS should use GFP_NOFS mode radix tree preloads rather than GFP_ATOMIC
allocations at radix-tree insertion-time.  This is important to reduce the
atomic memory requirement.

Signed-off-by: Nick Piggin <npiggin@suse.de>
Cc: Trond Myklebust <trond.myklebust@fys.uio.no>
Cc: "J. Bruce Fields" <bfields@fieldses.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-02-13 23:24:09 -05:00
Trond Myklebust
5d47a35600 NFS: Fix a potential file corruption issue when writing
If the inode is flagged as having an invalid mapping, then we can't rely on
the PageUptodate() flag. Ensure that we don't use the "anti-fragmentation"
write optimisation in nfs_updatepage(), since that will cause NFS to write
out areas of the page that are no longer guaranteed to be up to date.

A potential corruption could occur in the following scenario:

client 1			client 2
===============			===============
				fd=open("f",O_CREAT|O_WRONLY,0644);
				write(fd,"fubar\n",6);	// cache last page
				close(fd);
fd=open("f",O_WRONLY|O_APPEND);
write(fd,"foo\n",4);
close(fd);

				fd=open("f",O_WRONLY|O_APPEND);
				write(fd,"bar\n",4);
				close(fd);
-----
The bug may lead to the file "f" reading 'fubar\n\0\0\0\nbar\n' because
client 2 does not update the cached page after re-opening the file for
write. Instead it keeps it marked as PageUptodate() until someone calls
invaldate_inode_pages2() (typically by calling read()).

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-02-07 19:20:20 -05:00
Christoph Lameter
eebd2aa355 Pagecache zeroing: zero_user_segment, zero_user_segments and zero_user
Simplify page cache zeroing of segments of pages through 3 functions

zero_user_segments(page, start1, end1, start2, end2)

        Zeros two segments of the page. It takes the position where to
        start and end the zeroing which avoids length calculations and
	makes code clearer.

zero_user_segment(page, start, end)

        Same for a single segment.

zero_user(page, start, length)

        Length variant for the case where we know the length.

We remove the zero_user_page macro. Issues:

1. Its a macro. Inline functions are preferable.

2. The KM_USER0 macro is only defined for HIGHMEM.

   Having to treat this special case everywhere makes the
   code needlessly complex. The parameter for zeroing is always
   KM_USER0 except in one single case that we open code.

Avoiding KM_USER0 makes a lot of code not having to be dealing
with the special casing for HIGHMEM anymore. Dealing with
kmap is only necessary for HIGHMEM configurations. In those
configurations we use KM_USER0 like we do for a series of other
functions defined in highmem.h.

Since KM_USER0 is depends on HIGHMEM the existing zero_user_page
function could not be a macro. zero_user_* functions introduced
here can be be inline because that constant is not used when these
functions are called.

Also extract the flushing of the caches to be outside of the kmap.

[akpm@linux-foundation.org: fix nfs and ntfs build]
[akpm@linux-foundation.org: fix ntfs build some more]
Signed-off-by: Christoph Lameter <clameter@sgi.com>
Cc: Steven French <sfrench@us.ibm.com>
Cc: Michael Halcrow <mhalcrow@us.ibm.com>
Cc: <linux-ext4@vger.kernel.org>
Cc: Steven Whitehouse <swhiteho@redhat.com>
Cc: Trond Myklebust <trond.myklebust@fys.uio.no>
Cc: "J. Bruce Fields" <bfields@fieldses.org>
Cc: Anton Altaparmakov <aia21@cantab.net>
Cc: Mark Fasheh <mark.fasheh@oracle.com>
Cc: David Chinner <dgc@sgi.com>
Cc: Michael Halcrow <mhalcrow@us.ibm.com>
Cc: Steven French <sfrench@us.ibm.com>
Cc: Steven Whitehouse <swhiteho@redhat.com>
Cc: Trond Myklebust <trond.myklebust@fys.uio.no>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-05 09:44:13 -08:00
Linus Torvalds
75659ca0c1 Merge branch 'task_killable' of git://git.kernel.org/pub/scm/linux/kernel/git/willy/misc
* 'task_killable' of git://git.kernel.org/pub/scm/linux/kernel/git/willy/misc: (22 commits)
  Remove commented-out code copied from NFS
  NFS: Switch from intr mount option to TASK_KILLABLE
  Add wait_for_completion_killable
  Add wait_event_killable
  Add schedule_timeout_killable
  Use mutex_lock_killable in vfs_readdir
  Add mutex_lock_killable
  Use lock_page_killable
  Add lock_page_killable
  Add fatal_signal_pending
  Add TASK_WAKEKILL
  exit: Use task_is_*
  signal: Use task_is_*
  sched: Use task_contributes_to_load, TASK_ALL and TASK_NORMAL
  ptrace: Use task_is_*
  power: Use task_is_*
  wait: Use TASK_NORMAL
  proc/base.c: Use task_is_*
  proc/array.c: Use TASK_REPORT
  perfmon: Use task_is_*
  ...

Fixed up conflicts in NFS/sunrpc manually..
2008-02-01 11:45:47 +11:00
Chuck Lever
bf4285e75c NFS: Fix minor mixed sign comparison in NFS client's write logic
Clean up: PAGE_CACHE_SIZE is unsigned, and nfs_pageio_init() takes a size_t.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-01-30 02:06:01 -05:00
Trond Myklebust
0773769191 NFS/SUNRPC: Convert users of rpc_init_task+rpc_execute to rpc_run_task()
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-01-30 02:05:39 -05:00
Trond Myklebust
bdc7f021f3 NFS: Clean up the (commit|read|write)_setup() callback routines
Move the common code for setting up the nfs_write_data and nfs_read_data
structures into fs/nfs/read.c, fs/nfs/write.c and fs/nfs/direct.c.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-01-30 02:05:32 -05:00
Trond Myklebust
3ff7576dda SUNRPC: Clean up the initialisation of priority queue scheduling info.
We want the default scheduling priority (priority == 0) to remain
RPC_PRIORITY_NORMAL.

Also ensure that the priority wait queue scheduling is per process id
instead of sometimes being per thread, and sometimes being per inode.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-01-30 02:05:30 -05:00
Trond Myklebust
84115e1cd4 SUNRPC: Cleanup of rpc_task initialisation
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-01-30 02:05:30 -05:00
Trond Myklebust
acee478afc NFS: Clean up the write request locking.
Ensure that we set/clear NFS_PAGE_TAG_LOCKED when the nfs_page is hashed.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-01-30 02:05:24 -05:00
Matthew Wilcox
150030b78a NFS: Switch from intr mount option to TASK_KILLABLE
By using the TASK_KILLABLE infrastructure, we can get rid of the 'intr'
mount option.  We have to use _killable everywhere instead of _interruptible
as we get rid of rpc_clnt_sigmask/sigunmask.

Signed-off-by: Liam R. Howlett <howlett@gmail.com>
Signed-off-by: Matthew Wilcox <willy@linux.intel.com>
2007-12-06 17:40:25 -05:00
Adrian Bunk
5334eb13d4 NFS: make nfs_wb_page_priority() static
nfs_wb_page_priority() can now become static.

Signed-off-by: Adrian Bunk <bunk@kernel.org>
Cc: Trond Myklebust <trond.myklebust@fys.uio.no>
Cc: "J. Bruce Fields" <bfields@fieldses.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2007-11-26 16:24:48 -05:00
Trond Myklebust
61e930a904 NFS: Fix a writeback race...
This patch fixes a regression that was introduced by commit
44dd151d5c

We cannot zero the user page in nfs_mark_uptodate() any more, since

  a) We'd be modifying the page without holding the page lock
  b) We can race with other updates of the page, most notably
     because of the call to nfs_wb_page() in nfs_writepage_setup().

Instead, we do the zeroing in nfs_update_request() if we see that we're
creating a request that might potentially be marked as up to date.

Thanks to Olivier Paquet for reporting the bug and providing a test-case.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2007-10-19 17:18:57 -04:00
Peter Zijlstra
c9e51e4180 mm: count reclaimable pages per BDI
Count per BDI reclaimable pages; nr_reclaimable = nr_dirty + nr_unstable.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-17 08:42:45 -07:00
Peter Zijlstra
c4dc4beed2 nfs: remove congestion_end()
These patches aim to improve balance_dirty_pages() and directly address three
issues:
  1) inter device starvation
  2) stacked device deadlocks
  3) inter process starvation

1 and 2 are a direct result from removing the global dirty limit and using
per device dirty limits. By giving each device its own dirty limit is will
no longer starve another device, and the cyclic dependancy on the dirty limit
is broken.

In order to efficiently distribute the dirty limit across the independant
devices a floating proportion is used, this will allocate a share of the total
limit proportional to the device's recent activity.

3 is done by also scaling the dirty limit proportional to the current task's
recent dirty rate.

This patch:

nfs: remove congestion_end().  It's redundant, clear_bdi_congested() already
wakes the waiters.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Trond Myklebust <trond.myklebust@fys.uio.no>
Cc: "J. Bruce Fields" <bfields@fieldses.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-17 08:42:44 -07:00
Trond Myklebust
60ccd4ec41 NFS: Remove nfs_begin_data_update/nfs_end_data_update
The lower level routines in fs/nfs/proc.c, fs/nfs/nfs3proc.c and
fs/nfs/nfs4proc.c should already be dealing with the revalidation issues.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2007-10-09 17:19:53 -04:00
Trond Myklebust
cd3758e37d NFS: Replace file->private_data with calls to nfs_file_open_context()
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2007-10-09 17:18:31 -04:00
Trond Myklebust
7b159fc18d NFS: Fall back to synchronous writes when a background write errors...
This helps prevent huge queues of background writes from building up
whenever the server runs out of disk or quota space, or if someone changes
the file access modes behind our backs.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2007-10-09 17:15:23 -04:00
Trond Myklebust
34901f70d1 NFS: Writeback optimisation
Schedule writes using WB_SYNC_NONE first, then come back for a second pass
using WB_SYNC_ALL.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2007-10-09 17:15:21 -04:00