Commit graph

227 commits

Author SHA1 Message Date
Trond Myklebust 1ca018d28d pNFS: Fix a memory leak when attempted pnfs fails
pnfs_do_write() expects the call to pnfs_write_through_mds() to free the
pgio header and to release the layout segment before exiting. The problem
is that nfs_pgio_data_destroy() doesn't actually do this; it only frees
the memory allocated by nfs_generic_pgio().

Ditto for pnfs_do_read()...

Fix in both cases is to add a call to hdr->release(hdr).

Cc: stable@vger.kernel.org
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-06-17 20:00:26 -04:00
Trond Myklebust 21330b6670 Merge branch 'bugfixes'
* bugfixes:
  NFSv4: Return delegations synchronously in evict_inode
  SUNRPC: Fix a regression when reconnecting
  NFS: remount with security change should return EINVAL
  nfs: do not export discarded symbols
  NFSv4.1: don't export static symbol
2015-04-23 15:16:27 -04:00
Trond Myklebust 5bb89b4702 NFSv4.1/pnfs: Separate out metadata and data consistency for pNFS
The LAYOUTCOMMIT operation means different things to different layout types.
For blocks and objects, it is both a data and metadata consistency operation.
For files and flexfiles, it is only a metadata consistency operation.

This patch separates out the 2 cases, allowing the files/flexfiles layout
drivers to optimise away the data consistency calls to layoutcommit.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-03-27 12:39:38 -04:00
Trond Myklebust 7140171ea9 NFSv4.1/pnfs: Ensure we send layoutcommit before return-on-close
We must not send a close or delegreturn that would result in a
return-on-close of the layout without ensuring that we've also
sent the necessary layoutcommit.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-03-27 12:39:38 -04:00
Trond Myklebust 67af7611ec NFSv4.1/pnfs: Refactor pnfs_set_layoutcommit()
pnfs_set_layoutcommit() and pnfs_commit_set_layoutcommit() are 100% identical
except for the function arguments. Refactor to eliminate the difference.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-03-27 12:39:36 -04:00
Trond Myklebust 29559b11ae NFSv4.1/pnfs: Fix setting of layoutcommit last write byte
If the NFS_INO_LAYOUTCOMMIT flag was unset, then we _must_ ensure that
we also reset the last write byte (lwb) for that layout. The current
code depends on us clearing the lwb when we clear NFS_INO_LAYOUTCOMMIT,
which is not the case when we call pnfs_clear_layoutcommit().

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-03-27 12:39:35 -04:00
Julia Lawall 5b833825fd NFSv4.1: don't export static symbol
The semantic patch that fixes this problem is as follows:
(http://coccinelle.lip6.fr/)

// <smpl>
@r@
type T;
identifier f;
@@

static T f (...) { ... }

@@
identifier r.f;
declarer name EXPORT_SYMBOL_GPL;
@@

-EXPORT_SYMBOL_GPL(f);
// </smpl>

Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-03-12 11:53:11 -04:00
Dan Carpenter 4c21462acc pnfs: delete an unintended goto
There was an extra goto here where it shouldn't be, because of a merge
error.

Fixes: e2c63e091e ('Merge branch 'flexfiles'')
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-02-10 08:41:23 -05:00
Trond Myklebust 4ef2e4f84c NFSv4.1: Fix pnfs_put_lseg races
pnfs_layoutreturn_free_lseg_async() can also race with inode put in
the general case. We can now fix this, and also simplify the code.

Cc: Peng Tao <tao.peng@primarydata.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-02-05 23:44:18 -05:00
Trond Myklebust e4af440aaf NFSv4.1: pnfs_send_layoutreturn should use GFP_NOFS
In we want to be able to call pnfs_send_layoutreturn() from within the
writeback path, we really want it to use GFP_NOFS in order to prevent
recursion.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-02-05 22:16:50 -05:00
Trond Myklebust e2c63e091e Merge branch 'flexfiles'
* flexfiles: (53 commits)
  pnfs: lookup new lseg at lseg boundary
  nfs41: .init_read and .init_write can be called with valid pg_lseg
  pnfs: Update documentation on the Layout Drivers
  pnfs/flexfiles: Add the FlexFile Layout Driver
  nfs: count DIO good bytes correctly with mirroring
  nfs41: wait for LAYOUTRETURN before retrying LAYOUTGET
  nfs: add a helper to set NFS_ODIRECT_RESCHED_WRITES to direct writes
  nfs41: add NFS_LAYOUT_RETRY_LAYOUTGET to layout header flags
  nfs/flexfiles: send layoutreturn before freeing lseg
  nfs41: introduce NFS_LAYOUT_RETURN_BEFORE_CLOSE
  nfs41: allow async version layoutreturn
  nfs41: add range to layoutreturn args
  pnfs: allow LD to ask to resend read through pnfs
  nfs: add nfs_pgio_current_mirror helper
  nfs: only reset desc->pg_mirror_idx when mirroring is supported
  nfs41: add a debug warning if we destroy an unempty layout
  pnfs: fail comparison when bucket verifier not set
  nfs: mirroring support for direct io
  nfs: add mirroring support to pgio layer
  pnfs: pass ds_commit_idx through the commit path
  ...

Conflicts:
	fs/nfs/pnfs.c
	fs/nfs/pnfs.h
2015-02-03 16:01:27 -05:00
Weston Andros Adamson 7c13789e3e pnfs: lookup new lseg at lseg boundary
Before mirroring support was added, the pageio descriptor's pg_lseg was
set to null when an RPC was sent. Because of this, pg_init was called
at lseg boundaries with pg_lseg = NULL, and it could be set to the new
lseg.

Signed-off-by: Weston Andros Adamson <dros@primarydata.com>
2015-02-03 11:06:54 -08:00
Peng Tao cb5d04bc39 nfs41: .init_read and .init_write can be called with valid pg_lseg
With pgio refactoring in v3.15, .init_read and .init_write can be
called with valid pgio->pg_lseg. file layout was fixed at that time
by commit c6194271f (pnfs: filelayout: support non page aligned
layouts). But the generic helper still needs to be fixed.

Cc: stable@vger.kernel.org # 3.15+
Signed-off-by: Peng Tao <tao.peng@primarydata.com>
2015-02-03 11:06:53 -08:00
Tom Haynes d67ae825a5 pnfs/flexfiles: Add the FlexFile Layout Driver
The flexfile layout is a new layout that extends the
file layout. It is currently being drafted as a specification at
https://datatracker.ietf.org/doc/draft-ietf-nfsv4-layout-types/

Signed-off-by: Weston Andros Adamson <dros@primarydata.com>
Signed-off-by: Tom Haynes <loghyr@primarydata.com>
Signed-off-by: Tao Peng <bergwolf@primarydata.com>
2015-02-03 11:06:52 -08:00
Peng Tao aa8a45ee97 nfs41: wait for LAYOUTRETURN before retrying LAYOUTGET
Also take care to stop waiting if someone clears retry bit.

Signed-off-by: Peng Tao <tao.peng@primarydata.com>
2015-02-03 11:06:51 -08:00
Peng Tao c829013dca nfs41: add NFS_LAYOUT_RETRY_LAYOUTGET to layout header flags
Use it to indicate that LD wants to retry layoutget. LD can set
it whenever it wants the common pnfs code to return and retry
pnfs path through a new layout.

The bit gets cleared when client does a new layoutget, when client
closes the file (ROC case), or when kernel needs to evict the inode
(non-ROC case).

Signed-off-by: Peng Tao <tao.peng@primarydata.com>
2015-02-03 11:06:50 -08:00
Peng Tao 27b6f53987 nfs/flexfiles: send layoutreturn before freeing lseg
Otherwise we'll lose error tracking information when
encoding layoutreturn.

pnfs_put_lseg may be called from rpc callbacks. So we should not
call pnfs_send_layoutreturn directly because it can deadlock in
the rpc layer.

Signed-off-by: Peng Tao <tao.peng@primarydata.com>
Signed-off-by: Tom Haynes <loghyr@primarydata.com>
2015-02-03 11:06:50 -08:00
Peng Tao 193e3aa2cc nfs41: introduce NFS_LAYOUT_RETURN_BEFORE_CLOSE
When it is set, generic pnfs would try to send layoutreturn right
before last close/delegation_return regard less NFS_LAYOUT_ROC is
set or not. LD can then make sure layoutreturn is always sent
rather than being omitted.

The difference against NFS_LAYOUT_RETURN is that
NFS_LAYOUT_RETURN_BEFORE_CLOSE does not block usage of the layout so
LD can set it and expect generic layer to try pnfs path at the
same time.

Signed-off-by: Peng Tao <tao.peng@primarydata.com>
Signed-off-by: Tom Haynes <loghyr@primarydata.com>
2015-02-03 11:06:50 -08:00
Peng Tao 6c16605d6e nfs41: allow async version layoutreturn
Signed-off-by: Peng Tao <tao.peng@primarydata.com>
Signed-off-by: Tom Haynes <loghyr@primarydata.com>
2015-02-03 11:06:49 -08:00
Peng Tao 15eb67c153 nfs41: add range to layoutreturn args
So that callers can specify which range to return.

Signed-off-by: Peng Tao <tao.peng@primarydata.com>
Signed-off-by: Tom Haynes <loghyr@primarydata.com>
2015-02-03 11:06:49 -08:00
Peng Tao ceb11e13df pnfs: allow LD to ask to resend read through pnfs
If current IO cannot be completed due to some transient errors,
LD may want to ask generic layer to resend the request through
pnfs again.

Signed-off-by: Peng Tao <tao.peng@primarydata.com>
Signed-off-by: Tom Haynes <loghyr@primarydata.com>
2015-02-03 11:06:48 -08:00
Peng Tao 48d635f14a nfs: add nfs_pgio_current_mirror helper
Let it return current nfs_pgio_mirror in use depending on pg_mirror_count.
For read, we always use pg_mirrors[0], so this effectively gives us freedom
to use pg_mirror_idx to track the actual mirror to read from through out the
IO stack.

Signed-off-by: Peng Tao <tao.peng@primarydata.com>
Signed-off-by: Tom Haynes <loghyr@primarydata.com>
2015-02-03 11:06:48 -08:00
Peng Tao 566f873763 nfs41: add a debug warning if we destroy an unempty layout
So that we can detect the case if some layout segments are still
pinned which is surely a bug that we need to fix.

Signed-off-by: Peng Tao <tao.peng@primarydata.com>
2015-02-03 11:06:47 -08:00
Weston Andros Adamson a7d42ddb30 nfs: add mirroring support to pgio layer
This patch adds mirrored write support to the pgio layer. The default
is to use one mirror, but pgio callers may define callbacks to change
this to any value up to the (arbitrarily selected) limit of 16.

The basic idea is to break out members of nfs_pageio_descriptor that cannot
be shared between mirrored DSes and put them in a new structure.

Signed-off-by: Weston Andros Adamson <dros@primarydata.com>
2015-02-03 11:06:45 -08:00
Weston Andros Adamson 180bb5ec06 pnfs: release lseg in pnfs_generic_pg_cleanup
This is needed to support mirrored writes - the first write can't just
trash the lseg, we need to keep it around until all mirrors have
written.

Signed-off-by: Weston Andros Adamson <dros@primarydata.com>
2015-02-03 11:06:44 -08:00
Peng Tao e736a5b98c nfs41: clear NFS_LAYOUT_RETURN if layoutreturn is sent or failed to send
So that pnfs path is not disabled for ever.

Signed-off-by: Peng Tao <tao.peng@primarydata.com>
Signed-off-by: Tom Haynes <Thomas.Haynes@primarydata.com>
2015-02-03 11:06:42 -08:00
Peng Tao aa1e0e3a8e nfs41: send layoutreturn in last put_lseg
If current lseg is the last lseg marked with NFS_LSEG_LAYOUTRETURN,
send layoutreturn.

Signed-off-by: Peng Tao <tao.peng@primarydata.com>
Signed-off-by: Tom Haynes <Thomas.Haynes@primarydata.com>
2015-02-03 11:06:42 -08:00
Peng Tao ce6ab4f238 nfs41: don't use a layout if it is marked for returning
And if we are to return the same type of layouts, don't bother
sending more layoutgets.

Signed-off-by: Peng Tao <tao.peng@primarydata.com>
Signed-off-by: Tom Haynes <Thomas.Haynes@primarydata.com>
2015-02-03 11:06:41 -08:00
Peng Tao 016256df3a nfs41: add a helper to mark layout for return
It marks all matching layout segments as NFS_LSEG_LAYOUTRETURN,
which is an indicator for pnfs_put_lseg() to send layoutreturn,
and also prevents pnfs_update_layout() from using the returning
segments. Once it is set, it never gets cleared.

It also sets proper io failure bit so that pnfs path can be retried
after PNFS_LAYOUTGET_RETRY_TIMEOUT second.

Signed-off-by: Peng Tao <tao.peng@primarydata.com>
Signed-off-by: Tom Haynes <Thomas.Haynes@primarydata.com>
2015-02-03 11:06:41 -08:00
Peng Tao f40eb5d044 nfs41: make a helper function to send layoutreturn
It allows to specify different iomode to return.

Signed-off-by: Peng Tao <tao.peng@primarydata.com>
Signed-off-by: Tom Haynes <Thomas.Haynes@primarydata.com>
2015-02-03 11:06:41 -08:00
Peng Tao 4579d6b897 nfs41: pass iomode through layoutreturn args
So that it is possible to return a specific iomode layouts.

Signed-off-by: Peng Tao <tao.peng@primarydata.com>
Signed-off-by: Tom Haynes <Thomas.Haynes@primarydata.com>
2015-02-03 11:06:40 -08:00
Peng Tao 9bf87482dd nfs41: serialize first layoutget of a file
Per RFC 5661 Errata 3208:
| A client MAY always forget its layout state and associated
| layout stateid at any time (See also section 12.5.5.1).
| In such case, the client MUST use a non-layout stateid for the next
| LAYOUTGET operation. This will signal the server that the client has
| no more layouts on the file and its respective layout state can be
| released before issuing a new layout in response to LAYOUTGET.

In order to make such a signal unique to server, client needs to serialize
all layoutgets using non-layout stateid. We implement this by serializing
layoutgets when client has no layout segments at hand.

Signed-off-by: Peng Tao <tao.peng@primarydata.com>
Signed-off-by: Tom Haynes <Thomas.Haynes@primarydata.com>
2015-02-03 11:06:39 -08:00
Peng Tao abb9a0079c nfs41: close a small race window when adding new layout to global list
Signed-off-by: Peng Tao <tao.peng@primarydata.com>
Signed-off-by: Tom Haynes <Thomas.Haynes@primarydata.com>
2015-02-03 11:06:39 -08:00
Peng Tao 72cff4494e nfs/flexclient: export pnfs_layoutcommit_inode
flexfiles needs to start layoutcommit when necessary

Signed-off-by: Peng Tao <tao.peng@primarydata.com>
2015-02-03 11:06:38 -08:00
Trond Myklebust 40dd4b7aee NFSv4.1: Optimise layout return-on-close
Optimise the layout return on close code by ensuring that

1) Add a check for whether we hold a layout before taking any spinlocks
2) Only take the spin lock once
3) Use nfs_state->state to speed up open file checks

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-01-24 18:46:48 -05:00
Trond Myklebust 6543f80367 NFSv4.1/pnfs: replace broken pnfs_put_lseg_async
You cannot call pnfs_put_lseg_async() more than once per lseg, so it
is really an inappropriate way to deal with a refcount issue.

Instead, replace it with a function that decrements the refcount, and
puts the final 'free' operation (which is incompatible with locks) on
the workqueue.

Cc: Weston Andros Adamson <dros@primarydata.com>
Fixes: e6cf82d183: pnfs: add pnfs_put_lseg_async
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2014-10-08 16:45:43 -04:00
Christoph Hellwig c88953d87f pnfs: add return_range method
If a layout driver keeps per-inode state outside of the layout segments it
needs to be notified of any layout returns or recalls on an inode, and not
just about the freeing of layout segments.  Add a method to acomplish this,
which will allow the block layout driver to handle the case of truncated
and re-expanded files properly.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2014-09-10 12:47:03 -07:00
Christoph Hellwig 7c5d187581 pnfs: force a layout commit when encountering busy segments during recall
Expedite layout recall processing by forcing a layout commit when
we see busy segments.  Without it the layout recall might have to wait
until the VM decided to start writeback for the file, which can introduce
long delays.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2014-09-10 12:47:02 -07:00
Christoph Hellwig 5f919c9f10 pnfs: allow splicing pre-encoded pages into the layoutcommit args
Currently there is no XDR buffer space allocated for the per-layout driver
layoutcommit payload, which leads to server buffer overflows in the
blocklayout driver even under simple workloads.  As we can't do per-layout
sizes for XDR operations we'll have to splice a previously encoded list
of pages into the XDR stream, similar to how we handle ACL buffers.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2014-09-10 12:47:01 -07:00
Christoph Hellwig 47abadefad pnfs: avoid using stale stateids after layoutreturn
After we issued a layoutreturn operations the may free the layout stateid
and will thus cause bad stateid error when the client uses it again.

We currently try to avoid this case by chosing the open stateid if not
lsegs are present for this inode.  But various places can hold refererence
on lsegs and thus cause the list not to be empty shortly after a layout
return.  Add an explicit flag to mark the current layout stateid invalid
and force usage of the openstateid after we did a full file layoutreturn.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2014-09-10 12:47:01 -07:00
Christoph Hellwig 362f74745c pnfs: don't check sequence on new stateids in layoutget
When layoutget returns an entirely new layout stateid it should not
check the generation counter as the new stateid will start with a new
counter entirely unrelated to old one.

The current behavior causes constant layoutget failures against a block
server which allocates a new stateid after an recall that removed all
outstanding layouts.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2014-09-10 12:47:01 -07:00
Christoph Hellwig 1013df6115 pnfs: do not pass uninitialized lsegs to ->free_lseg
Ensure the lsegs are initialized early so that we don't pass an unitialized
one back to ->free_lseg during error processing.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2014-09-10 12:47:01 -07:00
Peng Tao 378520b837 nfs41: add a helper function to set layoutcommit after commit
Track lwb in nfs_commit_data so that we can use it to setup
layoutcommit in commit_done callback.

Signed-off-by: Peng Tao <tao.peng@primarydata.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2014-09-10 12:47:00 -07:00
Linus Torvalds 06b8ab5528 NFS client updates for Linux 3.17
Highlights include:
 
 - Stable fix for a bug in nfs3_list_one_acl()
 - Speed up NFS path walks by supporting LOOKUP_RCU
 - More read/write code cleanups
 - pNFS fixes for layout return on close
 - Fixes for the RCU handling in the rpcsec_gss code
 - More NFS/RDMA fixes
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Merge tag 'nfs-for-3.17-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs

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

   - stable fix for a bug in nfs3_list_one_acl()
   - speed up NFS path walks by supporting LOOKUP_RCU
   - more read/write code cleanups
   - pNFS fixes for layout return on close
   - fixes for the RCU handling in the rpcsec_gss code
   - more NFS/RDMA fixes"

* tag 'nfs-for-3.17-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs: (79 commits)
  nfs: reject changes to resvport and sharecache during remount
  NFS: Avoid infinite loop when RELEASE_LOCKOWNER getting expired error
  SUNRPC: remove all refcounting of groupinfo from rpcauth_lookupcred
  NFS: fix two problems in lookup_revalidate in RCU-walk
  NFS: allow lockless access to access_cache
  NFS: teach nfs_lookup_verify_inode to handle LOOKUP_RCU
  NFS: teach nfs_neg_need_reval to understand LOOKUP_RCU
  NFS: support RCU_WALK in nfs_permission()
  sunrpc/auth: allow lockless (rcu) lookup of credential cache.
  NFS: prepare for RCU-walk support but pushing tests later in code.
  NFS: nfs4_lookup_revalidate: only evaluate parent if it will be used.
  NFS: add checks for returned value of try_module_get()
  nfs: clear_request_commit while holding i_lock
  pnfs: add pnfs_put_lseg_async
  pnfs: find swapped pages on pnfs commit lists too
  nfs: fix comment and add warn_on for PG_INODE_REF
  nfs: check wait_on_bit_lock err in page_group_lock
  sunrpc: remove "ec" argument from encrypt_v2 operation
  sunrpc: clean up sparse endianness warnings in gss_krb5_wrap.c
  sunrpc: clean up sparse endianness warnings in gss_krb5_seal.c
  ...
2014-08-13 18:13:19 -06:00
Weston Andros Adamson e6cf82d183 pnfs: add pnfs_put_lseg_async
This is useful when lsegs need to be released while holding locks.

Signed-off-by: Weston Andros Adamson <dros@primarydata.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2014-08-03 17:05:25 -04:00
NeilBrown 743162013d sched: Remove proliferation of wait_on_bit() action functions
The current "wait_on_bit" interface requires an 'action'
function to be provided which does the actual waiting.
There are over 20 such functions, many of them identical.
Most cases can be satisfied by one of just two functions, one
which uses io_schedule() and one which just uses schedule().

So:
 Rename wait_on_bit and        wait_on_bit_lock to
        wait_on_bit_action and wait_on_bit_lock_action
 to make it explicit that they need an action function.

 Introduce new wait_on_bit{,_lock} and wait_on_bit{,_lock}_io
 which are *not* given an action function but implicitly use
 a standard one.
 The decision to error-out if a signal is pending is now made
 based on the 'mode' argument rather than being encoded in the action
 function.

 All instances of the old wait_on_bit and wait_on_bit_lock which
 can use the new version have been changed accordingly and their
 action functions have been discarded.
 wait_on_bit{_lock} does not return any specific error code in the
 event of a signal so the caller must check for non-zero and
 interpolate their own error code as appropriate.

The wait_on_bit() call in __fscache_wait_on_invalidate() was
ambiguous as it specified TASK_UNINTERRUPTIBLE but used
fscache_wait_bit_interruptible as an action function.
David Howells confirms this should be uniformly
"uninterruptible"

The main remaining user of wait_on_bit{,_lock}_action is NFS
which needs to use a freezer-aware schedule() call.

A comment in fs/gfs2/glock.c notes that having multiple 'action'
functions is useful as they display differently in the 'wchan'
field of 'ps'. (and /proc/$PID/wchan).
As the new bit_wait{,_io} functions are tagged "__sched", they
will not show up at all, but something higher in the stack.  So
the distinction will still be visible, only with different
function names (gds2_glock_wait versus gfs2_glock_dq_wait in the
gfs2/glock.c case).

Since first version of this patch (against 3.15) two new action
functions appeared, on in NFS and one in CIFS.  CIFS also now
uses an action function that makes the same freezer aware
schedule call as NFS.

Signed-off-by: NeilBrown <neilb@suse.de>
Acked-by: David Howells <dhowells@redhat.com> (fscache, keys)
Acked-by: Steven Whitehouse <swhiteho@redhat.com> (gfs2)
Acked-by: Peter Zijlstra <peterz@infradead.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Steve French <sfrench@samba.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/20140707051603.28027.72349.stgit@notabene.brown
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-07-16 15:10:39 +02:00
Weston Andros Adamson 53113ad35e pnfs: clean up *_resend_to_mds
Clean up pnfs_read_done_resend_to_mds and pnfs_write_done_resend_to_mds:
 - instead of passing all arguments from a nfs_pgio_header, just pass the header
 - share the common code

Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Weston Andros Adamson <dros@primarydata.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2014-06-24 18:47:01 -04:00
Weston Andros Adamson 4714fb51fd nfs: remove pgio_header refcount, related cleanup
The refcounting on nfs_pgio_header was related to there being (possibly)
more than one nfs_pgio_data. Now that nfs_pgio_data has been merged into
nfs_pgio_header, there is no reason to do this ref counting.  Just call
the completion callback on nfs_pgio_release/nfs_pgio_error.

Signed-off-by: Weston Andros Adamson <dros@primarydata.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2014-06-24 18:47:01 -04:00
Weston Andros Adamson d45f60c678 nfs: merge nfs_pgio_data into _header
struct nfs_pgio_data only exists as a member of nfs_pgio_header, but is
passed around everywhere, because there used to be multiple _data structs
per _header. Many of these functions then use the _data to find a pointer
to the _header.  This patch cleans this up by merging the nfs_pgio_data
structure into nfs_pgio_header and passing nfs_pgio_header around instead.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Weston Andros Adamson <dros@primarydata.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2014-06-24 18:47:00 -04:00
Weston Andros Adamson 1e7f3a4859 nfs: move nfs_pgio_data and remove nfs_rw_header
nfs_rw_header was used to allocate an nfs_pgio_header along with an
nfs_pgio_data, because a _header would need at least one _data.

Now there is only ever one nfs_pgio_data for each nfs_pgio_header -- move
it to nfs_pgio_header and get rid of nfs_rw_header.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Weston Andros Adamson <dros@primarydata.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2014-06-24 18:46:59 -04:00