In pNFS/flexfiles, we want to return the layout without necessarily marking
it as having completely failed. We therefore move the call to
pnfs_layout_io_set_failed() out of pnfs_error_mark_layout_for_return(),
and then ensura that pNFS/files layout calls it separately.
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

For ERESTARTSYS/EIO/EROFS/ENOSPC/E2BIG in layoutget, we
should just bail out instead of hiding the error and
retrying inband IO.

Change all the call sites to pop the error all the way up.
Signed-off-by: NPeng Tao <tao.peng@primarydata.com>
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

If filelayout_decode_layout fail, _filelayout_free_lseg will causes
a double freeing of fh_array.

[ 1179.279800] BUG: unable to handle kernel NULL pointer dereference at           (null)
[ 1179.280198] IP: [<ffffffffa027222d>] filelayout_free_fh_array.isra.11+0x1d/0x70 [nfs_layout_nfsv41_files]
[ 1179.281010] PGD 0
[ 1179.281443] Oops: 0000 [#1]
[ 1179.281831] Modules linked in: nfs_layout_nfsv41_files(OE) nfsv4(OE) nfs(OE) fscache(E) xfs libcrc32c coretemp nfsd crct10dif_pclmul ppdev crc32_pclmul crc32c_intel auth_rpcgss ghash_clmulni_intel nfs_acl lockd vmw_balloon grace sunrpc parport_pc vmw_vmci parport shpchp i2c_piix4 vmwgfx drm_kms_helper ttm drm serio_raw mptspi scsi_transport_spi mptscsih e1000 mptbase ata_generic pata_acpi [last unloaded: fscache]
[ 1179.283891] CPU: 0 PID: 13336 Comm: cat Tainted: G           OE   4.3.0-rc1-pnfs+ #244
[ 1179.284323] Hardware name: VMware, Inc. VMware Virtual Platform/440BX Desktop Reference Platform, BIOS 6.00 05/20/2014
[ 1179.285206] task: ffff8800501d48c0 ti: ffff88003e3c4000 task.ti: ffff88003e3c4000
[ 1179.285668] RIP: 0010:[<ffffffffa027222d>]  [<ffffffffa027222d>] filelayout_free_fh_array.isra.11+0x1d/0x70 [nfs_layout_nfsv41_files]
[ 1179.286612] RSP: 0018:ffff88003e3c77f8  EFLAGS: 00010202
[ 1179.287092] RAX: 0000000000000000 RBX: ffff88001fe78900 RCX: 0000000000000000
[ 1179.287731] RDX: ffffea0000f40760 RSI: ffff88001fe789c8 RDI: ffff88001fe789c0
[ 1179.288383] RBP: ffff88003e3c7810 R08: ffffea0000f40760 R09: 0000000000000000
[ 1179.289170] R10: 0000000000000000 R11: 0000000000000001 R12: ffff88001fe789c8
[ 1179.289959] R13: ffff88001fe789c0 R14: ffff88004ec05a80 R15: ffff88004f935b88
[ 1179.290791] FS:  00007f4e66bb5700(0000) GS:ffffffff81c29000(0000) knlGS:0000000000000000
[ 1179.291580] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 1179.292209] CR2: 0000000000000000 CR3: 00000000203f8000 CR4: 00000000001406f0
[ 1179.292731] Stack:
[ 1179.293195]  ffff88001fe78900 00000000000000d0 ffff88001fe78178 ffff88003e3c7868
[ 1179.293676]  ffffffffa0272737 0000000000000001 0000000000000001 ffff88001fe78800
[ 1179.294151]  00000000614fffce ffffffff81727671 ffff88001fe78100 ffff88001fe78100
[ 1179.294623] Call Trace:
[ 1179.295092]  [<ffffffffa0272737>] filelayout_alloc_lseg+0xa7/0x2d0 [nfs_layout_nfsv41_files]
[ 1179.295625]  [<ffffffff81727671>] ? out_of_line_wait_on_bit+0x81/0xb0
[ 1179.296133]  [<ffffffffa040407e>] pnfs_layout_process+0xae/0x320 [nfsv4]
[ 1179.296632]  [<ffffffffa03e0a01>] nfs4_proc_layoutget+0x2b1/0x360 [nfsv4]
[ 1179.297134]  [<ffffffffa0402983>] pnfs_update_layout+0x853/0xb30 [nfsv4]
[ 1179.297632]  [<ffffffffa039db24>] ? nfs_get_lock_context+0x74/0x170 [nfs]
[ 1179.298158]  [<ffffffffa0271807>] filelayout_pg_init_read+0x37/0x50 [nfs_layout_nfsv41_files]
[ 1179.298834]  [<ffffffffa03a72d9>] __nfs_pageio_add_request+0x119/0x460 [nfs]
[ 1179.299385]  [<ffffffffa03a6bd7>] ? nfs_create_request.part.9+0x37/0x2e0 [nfs]
[ 1179.299872]  [<ffffffffa03a7cc3>] nfs_pageio_add_request+0xa3/0x1b0 [nfs]
[ 1179.300362]  [<ffffffffa03a8635>] readpage_async_filler+0x85/0x260 [nfs]
[ 1179.300907]  [<ffffffff81180cb1>] read_cache_pages+0x91/0xd0
[ 1179.301391]  [<ffffffffa03a85b0>] ? nfs_read_completion+0x220/0x220 [nfs]
[ 1179.301867]  [<ffffffffa03a8dc8>] nfs_readpages+0x128/0x200 [nfs]
[ 1179.302330]  [<ffffffff81180ef3>] __do_page_cache_readahead+0x203/0x280
[ 1179.302784]  [<ffffffff81180dc8>] ? __do_page_cache_readahead+0xd8/0x280
[ 1179.303413]  [<ffffffff81181116>] ondemand_readahead+0x1a6/0x2f0
[ 1179.303855]  [<ffffffff81181371>] page_cache_sync_readahead+0x31/0x50
[ 1179.304286]  [<ffffffff811750a6>] generic_file_read_iter+0x4a6/0x5c0
[ 1179.304711]  [<ffffffffa03a0316>] ? __nfs_revalidate_mapping+0x1f6/0x240 [nfs]
[ 1179.305132]  [<ffffffffa039ccf2>] nfs_file_read+0x52/0xa0 [nfs]
[ 1179.305540]  [<ffffffff811e343c>] __vfs_read+0xcc/0x100
[ 1179.305936]  [<ffffffff811e3d15>] vfs_read+0x85/0x130
[ 1179.306326]  [<ffffffff811e4a98>] SyS_read+0x58/0xd0
[ 1179.306708]  [<ffffffff8172caaf>] entry_SYSCALL_64_fastpath+0x12/0x76
[ 1179.307094] Code: c4 66 66 66 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 55 48 89 e5 41 55 41 54 53 8b 07 49 89 f4 85 c0 74 47 48 8b 06 49 89 fd <48> 8b 38 48 85 ff 74 22 31 db eb 0c 48 63 d3 48 8b 3c d0 48 85
[ 1179.308357] RIP  [<ffffffffa027222d>] filelayout_free_fh_array.isra.11+0x1d/0x70 [nfs_layout_nfsv41_files]
[ 1179.309177]  RSP <ffff88003e3c77f8>
[ 1179.309582] CR2: 0000000000000000
Signed-off-by: NKinglong Mee <kinglongmee@gmail.com>
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

With the planned cgroup writeback support, backing-dev related
declarations will be more widely used across block and cgroup;
unfortunately, including backing-dev.h from include/linux/blkdev.h
makes cyclic include dependency quite likely.

This patch separates out backing-dev-defs.h which only has the
essential definitions and updates blkdev.h to include it.  c files
which need access to more backing-dev details now include
backing-dev.h directly.  This takes backing-dev.h off the common
include dependency chain making it a lot easier to use it across block
and cgroup.

v2: fs/fat build failure fixed.
Signed-off-by: NTejun Heo <tj@kernel.org>
Reviewed-by: NJan Kara <jack@suse.cz>
Cc: Jens Axboe <axboe@kernel.dk>
Signed-off-by: NJens Axboe <axboe@fb.com>

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: NTrond Myklebust <trond.myklebust@primarydata.com>

pnfs_set_layoutcommit() and pnfs_commit_set_layoutcommit() are 100% identical
except for the function arguments. Refactor to eliminate the difference.
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

Make it easier to grep for these functions by name.
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

Use of synchronize_rcu() when unmounting and potentially freeing a lot
of deviceids is problematic. There really is no reason why we can't just
use kfree_rcu() here.
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

The File Layout's filelayout_mark_request_commit() is almost the
Flex File Layout's ff_layout_mark_request_commit(). And that can
be reduced by calling into nfs_request_add_commit_list().
Signed-off-by: NTom Haynes <loghyr@primarydata.com>
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

Signed-off-by: NTom Haynes <loghyr@primarydata.com>
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

Pass ds_commit_idx through the nfs commit path. It's used to select
the commit bucket when using pnfs and is ignored when not using pnfs.
Several functions had to be changed: nfs_retry_commit,
nfs_mark_request_commit, pnfs_mark_request_commit and the pnfs layout
driver .mark_request_commit functions.
Signed-off-by: NTom Haynes <loghyr@primarydata.com>

'ds_commit_idx' is a better name - it is used to select the right
commit bucket for pnfs.
Signed-off-by: NWeston Andros Adamson <dros@primarydata.com>

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: NWeston Andros Adamson <dros@primarydata.com>

Instead of calling layoutreturn directly, call pnfs_error_mark_layout_for_return
to mark layouts for return and let generic code return layout when
layout segments are freed.
Signed-off-by: NPeng Tao <tao.peng@primarydata.com>
Signed-off-by: NTom Haynes <Thomas.Haynes@primarydata.com>

Conflicts:
	fs/nfs/filelayout/filelayout.c

so that flexfile layout client can pass in DS credential instead of
using user cred, which will be done in the next patch.
Signed-off-by: NPeng Tao <tao.peng@primarydata.com>
Signed-off-by: NTom Haynes <Thomas.Haynes@primarydata.com>

pnfs flexfile layout client may want to use NFSv3 ops rather
than the default MDS v4 ops.
Signed-off-by: NPeng Tao <tao.peng@primarydata.com>
Signed-off-by: NTom Haynes <Thomas.Haynes@primarydata.com>

Signed-off-by: NTom Haynes <loghyr@primarydata.com>

flexfile layout may need to set such when making DS connections.
Signed-off-by: NPeng Tao <tao.peng@primarydata.com>
Signed-off-by: NTom Haynes <Thomas.Haynes@primarydata.com>

They can be reused by flexfile layout as well.

Also add a code such that if read fails on one DS and
there are other DSes available to use, don't resend
through MDS but through pNFS so that client can read
from other DSes.
Reviewed-by: NJeff Layton <jlayton@primarydata.com>
Signed-off-by: NPeng Tao <tao.peng@primarydata.com>
Signed-off-by: NTom Haynes <Thomas.Haynes@primarydata.com>

flexfile layout may use different auth flavor as specified by MDS.
Reviewed-by: NJeff Layton <jlayton@primarydata.com>
Signed-off-by: NPeng Tao <tao.peng@primarydata.com>
Signed-off-by: NTom Haynes <Thomas.Haynes@primarydata.com>

It can be reused by flexfiles layout client.
Reviewed-by: NJeff Layton <jlayton@primarydata.com>
Signed-off-by: NPeng Tao <tao.peng@primarydata.com>
Signed-off-by: NTom Haynes <Thomas.Haynes@primarydata.com>

It can be reused by flexfile layout.
Reviewed-by: NJeff Layton <jlayton@primarydata.com>
Signed-off-by: NPeng Tao <tao.peng@primarydata.com>
Signed-off-by: NTom Haynes <Thomas.Haynes@primarydata.com>

Also pull nfs4_pnfs_ds_addr and nfs4_pnfs_ds to generic pnfs.

They can all be reused by flexfile layout as well.
Reviewed-by: NJeff Layton <jlayton@primarydata.com>
Signed-off-by: NPeng Tao <tao.peng@primarydata.com>
Signed-off-by: NTom Haynes <Thomas.Haynes@primarydata.com>

The flexfilelayout driver will share some common code
with the filelayout driver. This set of changes refactors
that common code out to avoid any module depenencies.
Signed-off-by: NTom Haynes <loghyr@primarydata.com>

Now that we got rid of the bdi abuse on character devices we can always use
sb->s_bdi to get at the backing_dev_info for a file, except for the block
device special case.  Export inode_to_bdi and replace uses of
mapping->backing_dev_info with it to prepare for the removal of
mapping->backing_dev_info.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NTejun Heo <tj@kernel.org>
Reviewed-by: NJan Kara <jack@suse.cz>
Signed-off-by: NJens Axboe <axboe@fb.com>

The nfs_put_client() function tests whether its argument is NULL and then
returns immediately. Thus the test around the call is not needed.

This issue was detected by using the Coccinelle software.
Signed-off-by: NMarkus Elfring <elfring@users.sourceforge.net>
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

NFSv4.x (x>0) requires us to call TEST_STATEID+FREE_STATEID if a stateid is
revoked. We will currently fail to do this if the stateid is a delegation.

http://lkml.kernel.org/r/CAN-5tyHwG=Cn2Q9KsHWadewjpTTy_K26ee+UnSvHvG4192p-Xw@mail.gmail.com
Cc: stable@vger.kernel.org
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

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: e6cf82d1: pnfs: add pnfs_put_lseg_async
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

Add support to the common pNFS core to issue GETDEVICEINFO calls on
a device ID cache miss.  The code is taken from the well debugged
file layout implementation and calls out to the layoutdriver through
a new alloc_deviceid_node method.  The calling conventions for
nfs4_find_get_deviceid are changed so that all information needed to
send a GETDEVICEINFO request is passed to the common code.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

Following http://www.rfc-editor.org/errata_search.php?rfc=5661&eid=2751
Don't set layoutcommit for commit_through_mds case.
For FILE_SYNC writes, don't set layoutcommit.
For DATA_SYNC wirtes, set layout commit right after wirtes done.
For UNSTABLE writes, set layout commit when commit done.
Signed-off-by: NPeng Tao <tao.peng@primarydata.com>
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

filelayout_retry_commit was recently split out from alloc_ds_commits,
but was done in such a way that the bucket pointer always starts at
index 0 no matter what the @idx argument is set to.

The intention of the @idx argument is to retry commits starting at
bucket @idx. This is called when alloc_ds_commits fails for a bucket.
Signed-off-by: NWeston Andros Adamson <dros@primarydata.com>
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

Signed-off-by: NWeston Andros Adamson <dros@primarydata.com>
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

nfs_page_find_head_request_locked looks through the regular nfs commit lists
when the page is swapped out, but doesn't look through the pnfs commit lists.

I'm not sure if anyone has hit any issues caused by this.
Suggested-by: NPeng Tao <tao.peng@primarydata.com>
Signed-off-by: NWeston Andros Adamson <dros@primarydata.com>
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

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: NNeilBrown <neilb@suse.de>
Acked-by: David Howells <dhowells@redhat.com> (fscache, keys)
Acked-by: Steven Whitehouse <swhiteho@redhat.com> (gfs2)
Acked-by: NPeter 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.brownSigned-off-by: NIngo Molnar <mingo@kernel.org>

Signed-off-by: NPeng Tao <tao.peng@primarydata.com>
Signed-off-by: NTom Haynes <Thomas.Haynes@primarydata.com>
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

We need to hold cinfo lock while setting bucket->wlseg and adding req to nwritten
list at the same time. Otherwise there might be a window where nwritten list
is empty yet we set bucket->wlseg, in which case ff_layout_scan_ds_commit_list()
may end up clearing bucket->wlseg incorrectly, casuing client to oops later on.

This was found when testing flexfile layout but filelayout has the same problem.
Signed-off-by: NPeng Tao <tao.peng@primarydata.com>
Signed-off-by: NTom Haynes <Thomas.Haynes@primarydata.com>
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

kcalloc manages count*sizeof overflow.

Cc: Trond Myklebust <trond.myklebust@primarydata.com>
Cc: linux-nfs@vger.kernel.org
Signed-off-by: NFabian Frederick <fabf@skynet.be>
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

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: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NWeston Andros Adamson <dros@primarydata.com>
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

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: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NWeston Andros Adamson <dros@primarydata.com>
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

Signed-off-by: NTom Haynes <Thomas.Haynes@primarydata.com>
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>