Commit Graph

1971 Commits

Author SHA1 Message Date
Benny Halevy 35c8bb543c NFSv4.1: use layout driver in global device cache
pnfs deviceids are unique per server, per layout type.
struct nfs_client is currently used to distinguish deviceids from
different nfs servers, yet these may clash between different layout
types on the same server.  Therefore, use the layout driver associated
with each deviceid at insertion time to look it up, unhash, or
delete it.

Signed-off-by: Benny Halevy <bhalevy@panasas.com>
2011-05-29 20:52:31 +03:00
Marc Eshel 1be5683b03 pnfs: CB_NOTIFY_DEVICEID
Note: This functionlaity is incomplete as all layout segments referring to
the 'to be removed device id' need to be reaped, and all in flight I/O drained.

[use be32 res in nfs4_callback_devicenotify]
[use nfs_client to qualify deviceid for cb_notify_deviceid]
[use global deviceid cache for CB_NOTIFY_DEVICEID]
[refactor device cache _lookup_deviceid]
[refactor device cache _find_get_deviceid]
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
[Bug in new global-device-cache code]
[layout_driver MUST set free_deviceid_node if using dev-cache]
Signed-off-by: Boaz Harrosh <bharrosh@panasas.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
2011-05-29 20:52:31 +03:00
Benny Halevy 1775bc342c NFSv4.1: purge deviceid cache on nfs_free_client
Use the pnfs_layoutdriver_type both as a qualifier for the deviceid,
distinguishing deviceid from different layout types on the server,
and for freeing the layout-driver allocated structure containing the
nfs4_deviceid_node.

[BUG in _deviceid_purge_client]
[layout_driver MUST set free_deviceid_node if using dev-cache]
[let ver < 4.1 compile]
Signed-off-by: Boaz Harrosh <bharrosh@panasas.com>
[removed EXPORT_SYMBOL_GPL(nfs4_deviceid_purge_client)]
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
2011-05-29 20:50:42 +03:00
Benny Halevy a1eaecbc4c NFSv4.1: make deviceid cache global
Move deviceid cache from the pnfs files layout driver to the
generic layer in preparation for the objects layout driver.

Signed-off-by: Benny Halevy <bhalevy@panasas.com>
2011-05-29 12:09:48 +03:00
Benny Halevy 45df3c8b0f pnfs: resolve header dependency in pnfs.h
Some definitions in the header file depend on nfs_fs.h so pnfs.h can't
be included independently.

Signed-off-by: Benny Halevy <bhalevy@panasas.com>
2011-05-29 12:09:48 +03:00
Benny Halevy 67d51f65bd NFSv4.1: use struct nfs_client to qualify deviceid
deviceids are unique per server, per layout type.
Therefore, in the global cache in the files layout driver
deviceids from different servers may clash so we need
to qualify them with a struct nfs_client that represents
the nfs server that returned the deviceid.

Introduced in 2.6.39 commit ea8eecdd
"NFSv4.1 move deviceid cache to filelayout driver"

Signed-off-by: Benny Halevy <bhalevy@panasas.com>
2011-05-29 12:09:47 +03:00
Jim Rees 3b6445a6f6 NFSv4.1: fix typo in filelayout_check_layout
Signed-off-by: Jim Rees <rees@umich.edu>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
2011-05-29 12:09:46 +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
Andy Adamson 2887fe4552 NFSv4.1: remove pnfs_layout_hdr from pnfs_destroy_all_layouts tmp_list
Prevents an infinite loop as list was never emptied.

Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2011-05-11 14:20:13 -04:00
Andy Adamson a8a4ae3a89 NFSv41: Resend on NFS4ERR_RETRY_UNCACHED_REP
Free the slot and resend the RPC with new session <slot#,seq#>.

For nfs4_async_handle_error, return -EAGAIN and set the task->tk_status to 0
to restart the async rpc in the rpc_restart_call_prepare state which resets
the slot.

For nfs4_handle_exception, retrying a call that uses nfs4_call_sync will
reset the slot via nfs41_call_sync_prepare.

For open/close/lock/locku/delegreturn/layoutcommit/unlink/rename/write
cachethis is true, so these operations will not trigger an
NFS4ERR_RETRY_UNCACHED_REP.

Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2011-05-11 14:01:33 -04:00
Jeff Layton 26c4c17073 nfs: don't lose MS_SYNCHRONOUS on remount of noac mount
On a remount, the VFS layer will clear the MS_SYNCHRONOUS bit on the
assumption that the flags on the mount syscall will have it set if the
remounted fs is supposed to keep it.

In the case of "noac" though, MS_SYNCHRONOUS is implied. A remount of
such a mount will lose the MS_SYNCHRONOUS flag since "sync" isn't part
of the mount options.

Reported-by: Max Matveev <makc@redhat.com>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Cc: stable@kernel.org
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2011-04-27 16:20:01 -04:00
Bryan Schumaker 613e901e1e NFS: Return meaningful status from decode_secinfo()
When compiling, I was getting this warning:
fs/nfs/nfs4xdr.c: In function ‘decode_secinfo’:
fs/nfs/nfs4xdr.c:4839:6: warning: variable ‘status’ set but not used
[-Wunused-but-set-variable]

We were unconditionally returning 0 as long as there wasn't an error
coming out of xdr_inline_decode().  We probably want to check the error
status coming out of decode_op_hdr() and decode_secinfo_gss(), rather
than assuming that everything is OK all the time.

Signed-off-by: Bryan Schumaker <bjschuma@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2011-04-27 16:17:29 -04:00
Trond Myklebust 28331a46d8 NFSv4: Ensure we request the ordinary fileid when doing readdirplus
When readdir() returns a directory entry for the root of a mounted
filesystem, Linux follows the old convention of returning the inode
number of the covered directory (despite newer versions of POSIX declaring
that this is a bug).
To ensure this continues to work, the NFSv4 readdir implementation requests
the 'mounted-on-fileid' from the server.

However, readdirplus also needs to instantiate an inode for this entry, and
for that, we also need to request the real fileid as per this patch.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2011-04-27 15:57:16 -04:00
Trond Myklebust 1bd714f2a1 NFSv4: Ensure that clientid and session establishment can time out
The following patch ensures that we do not get permanently trapped in
the RPC layer when trying to establish a new client id or session.
This again ensures that the state manager can finish in a timely
fashion when the last filesystem to reference the nfs_client exits.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2011-04-24 14:29:33 -04:00
Trond Myklebust fd954ae124 NFSv4.1: Don't loop forever in nfs4_proc_create_session
If a server for some reason keeps sending NFS4ERR_DELAY errors, we can end
up looping forever inside nfs4_proc_create_session, and so the usual
mechanisms for detecting if the nfs_client is dead don't work.

Fix this by ensuring that we loop inside the nfs4_state_manager thread
instead.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2011-04-24 14:28:18 -04:00
Bryan Schumaker fb8a5ba811 NFSv4: Handle NFS4ERR_WRONGSEC outside of nfs4_handle_exception()
I only want to try other secflavors during an initial mount if
NFS4ERR_WRONGSEC is returned.  nfs4_handle_exception() could
potentially map other errors to EPERM, so we should handle this
error specially for correctness.

Signed-off-by: Bryan Schumaker <bjschuma@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2011-04-18 17:06:00 -04:00
Bryan Schumaker 468f86134e NFSv4.1: Don't update sequence number if rpc_task is not sent
If we fail to contact the gss upcall program, then no message will
be sent to the server.  The client still updated the sequence number,
however, and this lead to NFS4ERR_SEQ_MISMATCH for the next several
RPC calls.

Signed-off-by: Bryan Schumaker <bjschuma@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2011-04-18 17:05:48 -04:00
Trond Myklebust 47c2199b6e NFSv4.1: Ensure state manager thread dies on last umount
Currently, the state manager may continue to try recovering state forever
even after the last filesystem to reference that nfs_client has umounted.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Cc: stable@kernel.org
2011-04-15 18:28:22 -04:00
Bryan Schumaker c3dfc2808a NFS: Use correct variable for page bounds checking
While decoding a secinfo reply, I store the list of supported sec
flavors on a page accessible through res->flavors.  Before reading
each new flavor, I do some math to determine if there is enough
space left on this page, and I break out of my read look if there
isn't.  In order to perform this check correctly, I need to use the
address of res->flavors, rather than the address of res.

When this loop was broken early I lied to the caller and told them
that the entire list had been decoded.  This could lead to problems
if the caller tries to use any the garbage data claiming to be a
valid sec flavor.  I fixed this by using res->flavors->num_flavors
as a counter, incrementing it every time a sec flavor is
successfully decoded.

Signed-off-by: Bryan Schumaker <bjschuma@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2011-04-13 15:12:23 -04:00
Bryan Schumaker 9b7160c55a NFS: don't negotiate when user specifies sec flavor
We were always attempting sec flavor negotiation, even if the user
told us a specific sec flavor to use.  If that sec flavor fails,
we should return an error rather than continuing with sec flavor
negotiation.

Signed-off-by: Bryan Schumaker <bjschuma@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2011-04-13 15:12:23 -04:00
Bryan Schumaker 801a16dc7b NFS: Attempt mount with default sec flavor first
nfs4_lookup_root() is already configured to use either RPC_AUTH_UNIX
or a user specified flavor (through -o sec=<whatever>).  We should
use this flavor first, and only attempt negotiation if it fails
with -EPERM.

Signed-off-by: Bryan Schumaker <bjschuma@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2011-04-13 15:12:23 -04:00
Bryan Schumaker 0fabee243a NFS: flav_array honors NFS_MAX_SECFLAVORS
NFS_MAX_SECFLAVORS should already take into account RPC_AUTH_UNIX
and RPC_AUTH_NULL, so we don't need to set aside extra slots
for them.

Signed-off-by: Bryan Schumaker <bjschuma@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2011-04-13 15:12:22 -04:00
Bryan Schumaker d1a8016a2d NFS: Fix infinite loop in gss_create_upcall()
There can be an infinite loop if gss_create_upcall() is called without
the userspace program running.  To prevent this, we return -EACCES if
we notice that pipe_version hasn't changed (indicating that the pipe
has not been opened).

Signed-off-by: Bryan Schumaker <bjschuma@netapp.com>

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2011-04-13 15:12:22 -04:00
Weston Andros Adamson 79a48a1f5d Don't mark_inode_dirty_sync() while holding lock
mark_inode_dirty_sync() grabs the same inode lock!

race conditions between holding the lock in pnfs_set_layoutcommit() and in
mark_inode_dirty_sync() can result in a second call to pnfs_layoutcommit_inode(), but
this will be a noop as NFS_INO_LAYOUTCOMMIT won't be set in the second call

Signed-off-by: Weston Andros Adamson <dros@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2011-04-13 13:15:51 -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
Bryan Schumaker 561f0b0ad0 NFS: Remove unused argument from nfs_find_best_sec()
The inode was used in an earlier version of the code, but it isn't
used anymore.

Signed-off-by: Bryan Schumaker <bjschuma@netapp.com>
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
Jesper Juhl 160bc1604f NFS: Remove dead code from nfs_fs_mount()
In fs/nfs/super.c::nfs_fs_mount() we test for a NULL 'data':

...
 		if (data == NULL || mntfh == NULL)
 			goto out_free_fh;
...

and then further down in the function we test 'data' again:

...
 			nfs_fscache_get_super_cookie(
 				s, data ? data->fscache_uniq : NULL, NULL);
...

this second check is just dead code since there is no way 'data' could
possibly be NULL here.
We also rely on a non-NULL 'data' in more than one location between these
two tests, further proving the point that the second test is bogus.

This patch removes the dead code.

Signed-off-by: Jesper Juhl <jj@chaosbits.net>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2011-04-12 19:34:21 -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
Linus Torvalds 94c8a984ae Merge branch 'bugfixes' of git://git.linux-nfs.org/projects/trondmy/nfs-2.6
* 'bugfixes' of git://git.linux-nfs.org/projects/trondmy/nfs-2.6:
  NFS: Change initial mount authflavor only when server returns NFS4ERR_WRONGSEC
  NFS: Fix a signed vs. unsigned secinfo bug
  Revert "net/sunrpc: Use static const char arrays"
2011-04-08 11:47:35 -07:00
Bryan Schumaker 37adb89fad NFS: Change initial mount authflavor only when server returns NFS4ERR_WRONGSEC
When attempting an initial mount, we should only attempt other
authflavors if AUTH_UNIX receives a NFS4ERR_WRONGSEC error.
This allows other errors to be passed back to userspace programs.

Signed-off-by: Bryan Schumaker <bjschuma@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2011-04-07 13:19:40 -07:00
Bryan Schumaker 418875900e NFS: Fix a signed vs. unsigned secinfo bug
rpc_authflavor_t is cast from an unsigned int, but the
initial code tried to use it as a signed int.  I fix
this by passing an rpc_authflavor_t pointer around, and
returning signed integers from functions.

Signed-off-by: Bryan Schumaker <bjschuma@netapp.com>
Reported-by: Dan Carpenter <error27@gmail.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2011-04-06 13:25:04 -07:00
Lucas De Marchi 25985edced Fix common misspellings
Fixes generated by 'codespell' and manually reviewed.

Signed-off-by: Lucas De Marchi <lucas.demarchi@profusion.mobi>
2011-03-31 11:26:23 -03:00
Dave Chinner 0444d76ae6 fs: don't use igrab() while holding i_lock
Fix the incorrect use of igrab() inside the i_lock in NFS and Ceph‥

If we are already holding the i_lock, we have a reference to the
inode so we can safely use ihold() to gain an extra reference. This
avoids hangs due to lock recursion on the i_lock now that the
inode_lock is gone and igrab() uses the i_lock itself.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: linux-fsdevel@vger.kernel.org
Cc: Ryan Mallon <ryan@bluewatersys.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-03-29 07:50:34 -07:00
Trond Myklebust a0e7e3cf79 NFS: Don't leak RPC clients in NFSv4 secinfo negotiation
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2011-03-27 17:48:17 +02:00
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
Trond Myklebust 0acd220192 Merge branch 'nfs-for-2.6.39' into nfs-for-next 2011-03-24 17:03:14 -04:00
Weston Andros Adamson 35124a0994 Cleanup XDR parsing for LAYOUTGET, GETDEVICEINFO
changes LAYOUTGET and GETDEVICEINFO XDR parsing to:
 - not use vmap, which doesn't work on incoherent archs
 - use xdr_stream parsing for all xdr

Signed-off-by: Weston Andros Adamson <dros@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2011-03-24 17:01:41 -04:00
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 de4b15c7e9 NFSv4.1 pnfs_layoutcommit_inode fixes
Test NFS_INO_LAYOUTCOMMIT before kzalloc
Mark inode dirty to retry LAYOUTCOMMIT on kzalloc failure.
Add comments.

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
Bryan Schumaker 8f70e95f9f NFS: Determine initial mount security
When sec=<something> is not presented as a mount option,
we should attempt to determine what security flavor the
server is using.

Signed-off-by: Bryan Schumaker <bjschuma@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2011-03-24 13:52:42 -04:00
Bryan Schumaker 7ebb931598 NFS: use secinfo when crossing mountpoints
A submount may use different security than the parent
mount does.  We should figure out what sec flavor the
submount uses at mount time.

Signed-off-by: Bryan Schumaker <bjschuma@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2011-03-24 13:52:42 -04:00
Bryan Schumaker 5a5ea0d485 NFS: Add secinfo procedure
This patch adds the nfs4 operation secinfo as a
valid nfs rpc operation.

Signed-off-by: Bryan Schumaker <bjschuma@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2011-03-24 13:52:41 -04:00
Bryan Schumaker 7c5130588d NFS: lookup supports alternate client
A later patch will need to perform a lookup using an
alternate client with a different security flavor.
This patch adds support for doing that on NFS v4.

Signed-off-by: Bryan Schumaker <bjschuma@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2011-03-24 13:52:41 -04:00
Bryan Schumaker e73b83f270 NFS: convert call_sync() to a function
This patch changes nfs4_call_sync() from a macro into a
static inline function.  As a macro, the call_sync()
function will not do any type checking and depends
on the sequence arguments always having the same name.
As a function, we get to have type checking and can
rename the arguments if we so choose.

Signed-off-by: Bryan Schumaker <bjschuma@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2011-03-24 13:52:41 -04:00
Fred Isaman cccb4d063b NFSv4.1 remove temp code that prevented ds commits
Now that all the infrastructure is in place, we will do the
right thing if we remove this special casing.

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
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