PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} macros were introduced *long* time
ago with promise that one day it will be possible to implement page
cache with bigger chunks than PAGE_SIZE.

This promise never materialized.  And unlikely will.

We have many places where PAGE_CACHE_SIZE assumed to be equal to
PAGE_SIZE.  And it's constant source of confusion on whether
PAGE_CACHE_* or PAGE_* constant should be used in a particular case,
especially on the border between fs and mm.

Global switching to PAGE_CACHE_SIZE != PAGE_SIZE would cause to much
breakage to be doable.

Let's stop pretending that pages in page cache are special.  They are
not.

The changes are pretty straight-forward:

 - <foo> << (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> <foo>;

 - <foo> >> (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> <foo>;

 - PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} -> PAGE_{SIZE,SHIFT,MASK,ALIGN};

 - page_cache_get() -> get_page();

 - page_cache_release() -> put_page();

This patch contains automated changes generated with coccinelle using
script below.  For some reason, coccinelle doesn't patch header files.
I've called spatch for them manually.

The only adjustment after coccinelle is revert of changes to
PAGE_CAHCE_ALIGN definition: we are going to drop it later.

There are few places in the code where coccinelle didn't reach.  I'll
fix them manually in a separate patch.  Comments and documentation also
will be addressed with the separate patch.

virtual patch

@@
expression E;
@@
- E << (PAGE_CACHE_SHIFT - PAGE_SHIFT)
+ E

@@
expression E;
@@
- E >> (PAGE_CACHE_SHIFT - PAGE_SHIFT)
+ E

@@
@@
- PAGE_CACHE_SHIFT
+ PAGE_SHIFT

@@
@@
- PAGE_CACHE_SIZE
+ PAGE_SIZE

@@
@@
- PAGE_CACHE_MASK
+ PAGE_MASK

@@
expression E;
@@
- PAGE_CACHE_ALIGN(E)
+ PAGE_ALIGN(E)

@@
expression E;
@@
- page_cache_get(E)
+ get_page(E)

@@
expression E;
@@
- page_cache_release(E)
+ put_page(E)
Signed-off-by: NKirill A. Shutemov <kirill.shutemov@linux.intel.com>
Acked-by: NMichal Hocko <mhocko@suse.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

I noticed that all the callers of this function pass cinfo->mds->list as
an argument in addition to the cinfo structure itself.  Let's get rid of
the extra argument, since it doesn't seem to be adding anything.
Signed-off-by: NAnna Schumaker <Anna.Schumaker@Netapp.com>
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

The use of wait_on_atomic_t() for waiting on I/O to complete before
unlocking allows us to git rid of the NFS_IO_INPROGRESS flag, and thus the
nfs_iocounter's flags member, and finally the nfs_iocounter altogether.
The count of I/O is moved to the lock context, and the counter
increment/decrement functions become simple enough to open-code.
Signed-off-by: NBenjamin Coddington <bcodding@redhat.com>
[Trond: Fix up conflict with existing function nfs_wait_atomic_killable()]
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

If two processes share the same credentials and NFSv4 open stateid, then
allow them both to dirty the same page, even if their nfs_open_context
differs.
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

If the layout segment is invalid, then we should not be adding more
write requests to the commit list. Instead, those writes should be
replayed after requesting a new layout.
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

Allow synchronous RPC calls to wait for pending RPC calls to finish,
but also allow asynchronous ones to just fire off another commit.

With this patch, the xfstests generic/074 test completes in 226s
instead of 242s
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

The flexfiles layout in particular, seems to want to poke around in the
O_DIRECT flags when retransmitting.
This patch sets up an interface to allow it to call back into O_DIRECT
to handle retransmission correctly. It also fixes a potential bug whereby
we could change the behaviour of O_DIRECT if an error is already pending.
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

Instead of dropping pages when write fails, only do it when
we get fatal failure in launder_page write back.
Signed-off-by: NPeng Tao <tao.peng@primarydata.com>
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

When we fail to queue a read page to IO descriptor,
we need to clean it up otherwise it is hanging around
preventing nfs module from being removed.

When we fail to queue a write page to IO descriptor,
we need to clean it up and also save the failure status
to open context. Then at file close, we can try to write
pages back again and drop the page if it fails to writeback
in .launder_page, which will be done in the next patch.
Signed-off-by: NPeng Tao <tao.peng@primarydata.com>
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

If there are already writes queued up for commit, then don't flush
just this page even if it is a reclaim issue.
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

Background flush is needed in order to satisfy the global page limits.
Don't subvert by reducing the priority.
This should also address a write starvation issue that was reported by
Neil Brown.
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

If non rpc-based layout driver return bad length of data, nfs retries
by calling rpc_restart_call_prepare() that cause an NULL reference panic.

This patch lets nfs retry through MDS for non rpc-based layout driver
return bad length of data.

[13034.883329] BUG: unable to handle kernel NULL pointer dereference at           (null)
[13034.884902] IP: [<ffffffffa00db372>] rpc_restart_call_prepare+0x62/0x90 [sunrpc]
[13034.886558] PGD 0
[13034.888126] Oops: 0000 [#1] KASAN
[13034.889710] Modules linked in: blocklayoutdriver(OE) nfsv4(OE) nfs(OE) fscache(E) nfsd(OE) xfs libcrc32c coretemp btrfs crct10dif_pclmul crc32_pclmul crc32c_intel ghash_clmulni_intel ppdev vmw_balloon auth_rpcgss shpchp nfs_acl lockd vmw_vmci parport_pc xor raid6_pq grace parport sunrpc i2c_piix4 vmwgfx drm_kms_helper ttm drm mptspi e1000 serio_raw scsi_transport_spi mptscsih mptbase ata_generic pata_acpi [last unloaded: fscache]
[13034.898260] CPU: 0 PID: 10112 Comm: kworker/0:1 Tainted: G           OE   4.3.0-rc5+ #279
[13034.899932] Hardware name: VMware, Inc. VMware Virtual Platform/440BX Desktop Reference Platform, BIOS 6.00 07/02/2015
[13034.903342] Workqueue: events bl_read_cleanup [blocklayoutdriver]
[13034.905059] task: ffff88006a9148c0 ti: ffff880035e90000 task.ti: ffff880035e90000
[13034.906827] RIP: 0010:[<ffffffffa00db372>]  [<ffffffffa00db372>] rpc_restart_call_prepare+0x62/0x90 [sunrpc]
[13034.910522] RSP: 0018:ffff880035e97b58  EFLAGS: 00010282
[13034.912378] RAX: fffffbfff04a5a94 RBX: ffff880068fe4858 RCX: 0000000000000003
[13034.914339] RDX: dffffc0000000000 RSI: 0000000000000003 RDI: 0000000000000282
[13034.916236] RBP: ffff880035e97b68 R08: 0000000000000001 R09: 0000000000000001
[13034.918229] R10: 0000000000000000 R11: 0000000000000001 R12: 0000000000000000
[13034.920007] R13: ffff880068fe4858 R14: ffff880068fe4a60 R15: 0000000000001000
[13034.921845] FS:  0000000000000000(0000) GS:ffffffff82247000(0000) knlGS:0000000000000000
[13034.923645] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[13034.925525] CR2: 0000000000000000 CR3: 00000000063dd000 CR4: 00000000001406f0
[13034.932808] Stack:
[13034.934813]  ffff880068fe4780 0000000000001000 ffff880035e97ba8 ffffffffa08800d2
[13034.936675]  ffffffffa088029d ffff880068fe4780 ffff880068fe4858 ffffffffa089c0a0
[13034.938593]  ffff880068fe47e0 ffff88005d59faf0 ffff880035e97be0 ffffffffa087e08f
[13034.940454] Call Trace:
[13034.942388]  [<ffffffffa08800d2>] nfs_readpage_result+0x112/0x200 [nfs]
[13034.944317]  [<ffffffffa088029d>] ? nfs_readpage_done+0xdd/0x160 [nfs]
[13034.946267]  [<ffffffffa087e08f>] nfs_pgio_result+0x9f/0x120 [nfs]
[13034.948166]  [<ffffffffa09266cc>] pnfs_ld_read_done+0x7c/0x1e0 [nfsv4]
[13034.950247]  [<ffffffffa03b07ee>] bl_read_cleanup+0x2e/0x60 [blocklayoutdriver]
[13034.952156]  [<ffffffff810ebf62>] process_one_work+0x412/0x870
[13034.954102]  [<ffffffff810ebe84>] ? process_one_work+0x334/0x870
[13034.955949]  [<ffffffff810ebb50>] ? queue_delayed_work_on+0x40/0x40
[13034.957985]  [<ffffffff810ec441>] worker_thread+0x81/0x6a0
[13034.959817]  [<ffffffff810ec3c0>] ? process_one_work+0x870/0x870
[13034.961785]  [<ffffffff810f43bd>] kthread+0x17d/0x1a0
[13034.963544]  [<ffffffff810f4240>] ? kthread_create_on_node+0x330/0x330
[13034.965479]  [<ffffffff81100428>] ? finish_task_switch+0x88/0x220
[13034.967223]  [<ffffffff810f4240>] ? kthread_create_on_node+0x330/0x330
[13034.968929]  [<ffffffff81b6ae5f>] ret_from_fork+0x3f/0x70
[13034.970534]  [<ffffffff810f4240>] ? kthread_create_on_node+0x330/0x330
[13034.972176] Code: c7 43 50 40 84 0d a0 e8 3d fe 1c e1 48 8d 7b 58 c7 83 e4 00 00 00 00 00 00 00 e8 ca fe 1c e1 4c 8b 63 58 4c 89 e7 e8 be fe 1c e1 <49> 83 3c 24 00 74 12 48 c7 43 50 f0 a2 0e a0 b8 01 00 00 00 5b
[13034.977148] RIP  [<ffffffffa00db372>] rpc_restart_call_prepare+0x62/0x90 [sunrpc]
[13034.978780]  RSP <ffff880035e97b58>
[13034.980399] CR2: 0000000000000000
Signed-off-by: NKinglong Mee <kinglongmee@gmail.com>
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

If all other conditions in nfs_can_extend_write() are met, and there
are no locks, then we should be able to assume close-to-open semantics
and the ability to extend our write to cover the whole page.

With this patch, the xfstests generic/074 test completes in 242s instead
of >1400s on my test rig.

Fixes: bd61e0a9 ("locks: convert posix locks to file_lock_context")
Cc: Jeff Layton <jlayton@primarydata.com>
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

Currently, we are crediting all the calls to nfs_writepages_callback()
(i.e. the nfs_writepages() callback) to nfs_writepage(). Aside from
being inconsistent with the behaviour of the equivalent readpage/readpages
accounting, this also means that we cannot distinguish between bulk writes
and single page writebacks (which confuses the 'nfsiostat -p' tool).
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

There is a reference leak of layout segment after resetting
pageio read/write to mds.
Signed-off-by: NKinglong Mee <kinglongmee@gmail.com>
Cc: stable@vger.kernel.org # v4.0+
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

All nfs_write_inode() does is pass its arguments to
nfs_commit_unstable_pages().  Let's cut out the middle man and have
nfs_write_pages() do the work directly.
Signed-off-by: NAnna Schumaker <Anna.Schumaker@Netapp.com>
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

pnfs_layout_mark_request_commit() needs to ensure that it adds the
request to the commit list atomically with all the other updates
in order to prevent corruption to buckets[ds_commit_idx].wlseg
due to races with pnfs_generic_clear_request_commit().

Fixes: 338d00cf ("pnfs: Refactor the *_layout_mark_request_commit...")
Cc: stable@vger.kernel.org # v4.0+
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

pNFS writes don't return attributes, however that doesn't mean that we
should ignore the fact that they may be extending the file. This patch
ensures that if a write is seen to extend the file, then we always set
an attribute barrier, and update the cached file size.
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

Before rpc_run_task(), tk_pid is uninitiated as 0 always.
Signed-off-by: NKinglong Mee <kinglongmee@gmail.com>
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

If a write attempt fails, and the write is queued up for resending to
the server, as opposed to being dropped, then we need to set the
appropriate flag so that nfs_file_fsync() does the right thing.

Cc: stable@vger.kernel.org
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

This was only ever set to nfs_writeback_release_common(), a function
which is completely empty.  Let's just drop this function pointer and
simplify the code a bit.
Signed-off-by: NAnna Schumaker <Anna.Schumaker@Netapp.com>
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

Currently, a bdi (backing_dev_info) embeds single wb (bdi_writeback)
and the role of the separation is unclear.  For cgroup support for
writeback IOs, a bdi will be updated to host multiple wb's where each
wb serves writeback IOs of a different cgroup on the bdi.  To achieve
that, a wb should carry all states necessary for servicing writeback
IOs for a cgroup independently.

This patch moves bdi->bdi_stat[] into wb.

* enum bdi_stat_item is renamed to wb_stat_item and the prefix of all
  enums is changed from BDI_ to WB_.

* BDI_STAT_BATCH() -> WB_STAT_BATCH()

* [__]{add|inc|dec|sum}_wb_stat(bdi, ...) -> [__]{add|inc}_wb_stat(wb, ...)

* bdi_stat[_error]() -> wb_stat[_error]()

* bdi_writeout_inc() -> wb_writeout_inc()

* stat init is moved to bdi_wb_init() and bdi_wb_exit() is added and
  frees stat.

* As there's still only one bdi_writeback per backing_dev_info, all
  uses of bdi->stat[] are mechanically replaced with bdi->wb.stat[]
  introducing no behavior changes.
Signed-off-by: NTejun Heo <tj@kernel.org>
Reviewed-by: NJan Kara <jack@suse.cz>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Wu Fengguang <fengguang.wu@intel.com>
Cc: Miklos Szeredi <miklos@szeredi.hu>
Cc: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: NJens Axboe <axboe@fb.com>

When running the Connectathon basic tests against a Solaris NFS
server over NFSv4.0, test5 reports that stat(2) returns a file size
of zero instead of 1MB.

On success, nfs_commit_inode() can return a positive result; see
other call sites such as nfs_file_fsync_commit() and
nfs_commit_unstable_pages().

The call site recently added in nfs_wb_all() does not prevent that
positive return value from leaking to its callers. If it leaks
through nfs_sync_inode() back to nfs_getattr(), that causes stat(2)
to return a positive return value to user space while also not
filling in the passed-in struct stat.

Additional clean up: the new logic in nfs_wb_all() is rewritten in
bfields-normal form.

Fixes: 5bb89b47 ("NFSv4.1/pnfs: Separate out metadata . . .")
Signed-off-by: NChuck Lever <chuck.lever@oracle.com>
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

This reverts commit 5a254d08.

Since commit 5a254d08 ("nfs: replace nfs_add_stats with
nfs_inc_stats when add one"), nfs_readpage and nfs_do_writepage use
nfs_inc_stats to increment NFSIOS_READPAGES and NFSIOS_WRITEPAGES
instead of nfs_add_stats.

However nfs_inc_stats does not do the same thing as nfs_add_stats with
value 1 because these functions work on distinct stats:
nfs_inc_stats increments stats from "enum nfs_stat_eventcounters" (in
server->io_stats->events) and nfs_add_stats those from "enum
nfs_stat_bytecounters" (in server->io_stats->bytes).
Signed-off-by: NNicolas Iooss <nicolas.iooss_linux@m4x.org>
Fixes: 5a254d08 ("nfs: replace nfs_add_stats with nfs_inc_stats...")
Cc: stable@vger.kernel.org # 3.19+
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

that's the bulk of filesystem drivers dealing with inodes of their own
Signed-off-by: NDavid Howells <dhowells@redhat.com>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

This patch replaces cancel_dirty_page() with a helper function
account_page_cleaned() which only updates counters.  It's called from
truncate_complete_page() and from try_to_free_buffers() (hack for ext3).
Page is locked in both cases, page-lock protects against concurrent
dirtiers: see commit 2d6d7f98 ("mm: protect set_page_dirty() from
ongoing truncation").

Delete_from_page_cache() shouldn't be called for dirty pages, they must
be handled by caller (either written or truncated).  This patch treats
final dirty accounting fixup at the end of __delete_from_page_cache() as
a debug check and adds WARN_ON_ONCE() around it.  If something removes
dirty pages without proper handling that might be a bug and unwritten
data might be lost.

Hugetlbfs has no dirty pages accounting, ClearPageDirty() is enough
here.

cancel_dirty_page() in nfs_wb_page_cancel() is redundant.  This is
helper for nfs_invalidate_page() and it's called only in case complete
invalidation.

The mess was started in v2.6.20 after commits 46d2277c ("Clean up
and make try_to_free_buffers() not race with dirty pages") and
3e67c098 ("truncate: clear page dirtiness before running
try_to_free_buffers()") first was reverted right in v2.6.20 in commit
ecdfc978 ("Resurrect 'try_to_free_buffers()' VM hackery"), second in
v2.6.25 commit a2b34564 ("Fix dirty page accounting leak with ext3
data=journal").

Custom fixes were introduced between these points.  NFS in v2.6.23, commit
1b3b4a1a ("NFS: Fix a write request leak in nfs_invalidate_page()").
Kludge in __delete_from_page_cache() in v2.6.24, commit 3a692790 ("Do
dirty page accounting when removing a page from the page cache").  Since
v2.6.25 all of them are redundant.

[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: NKonstantin Khlebnikov <khlebnikov@yandex-team.ru>
Cc: Tejun Heo <tj@kernel.org>
Cc: Jan Kara <jack@suse.cz>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

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>

Ensure that other operations that race with our write RPC calls
cannot revert the file size updates that were made on the server.
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>
Tested-by: NChuck Lever <chuck.lever@oracle.com>

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>

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: NWeston Andros Adamson <dros@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>

This is needed for mirrored DS support, where multuple requests
cover the same range.
Signed-off-by: NWeston Andros Adamson <dros@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>

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>

We can now add a dedicated spinlock without expanding struct inode.
Change to using that to protect the various i_flctx lists.
Signed-off-by: NJeff Layton <jlayton@primarydata.com>
Acked-by: NChristoph Hellwig <hch@lst.de>

Signed-off-by: NJeff Layton <jlayton@primarydata.com>
Acked-by: NChristoph Hellwig <hch@lst.de>

Signed-off-by: NJeff Layton <jlayton@primarydata.com>
Acked-by: NChristoph Hellwig <hch@lst.de>

Signed-off-by: NLi RongQing <roy.qing.li@gmail.com>
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>