Commit 57208fa7 "NFS: Create an write_pageio_init() function"
did not modify the calls in direct.c, preventing direct io from
using pnfs.  This reintroduces that capability.
Signed-off-by: NFred Isaman <iisaman@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Commit 1abb5088 "NFS: Create an read_pageio_init() function"
did not modify the call in direct.c, preventing direct io from
using pnfs.  This reintroduces that capability.
Signed-off-by: NFred Isaman <iisaman@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Fix 2 bugs in nfs_direct_write_reschedule:

 - The request needs to be removed from the 'reqs' list before it can
   be added to 'failed'.
 - Fix an infinite loop if the 'failed' list is non-empty.
Reported-by: NJulia Lawall <julia.lawall@lip6.fr>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

In nfs_direct_write_reschedule(), the requests from nfs_scan_commit_list
have a refcount of 2, whereas the operations in
nfs_direct_write_completion_ops expect them to have a refcount of 1.

This patch adds a call to release the extra references.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>
Cc: Fred Isaman <iisaman@netapp.com>

This reverts a hunk from commit 04277086
"NFS: Clean up - Simplify reference counting in fs/nfs/direct.c"

The cleanups in that patch affect the write path, but by the time
processing hits commit the removed reference has been added back by
nfs_scan_commit_list().  Without this reversion, any page that is
sent to commit holds on to an unbalanced reference that is never
freed.  The immediate effect is an imbalance over the wire between
OPENs and CLOSEs.
Signed-off-by: NFred Isaman <iisaman@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

The new commit code fails to copy the verifier into the wb_verf field
of _all_ the nfs_page structures; it only copies it into the first entry.
The consequence is that most requests end up failing to match in
nfs_commit_release.

Fix is to copy the verifier into the req->wb_verf field in
nfs_write_completion.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>
Cc: Fred Isaman <iisaman@netapp.com>

Use the same mechanism as the block devices are using, but move the
helper functions from fs/direct-io.c into fs/inode.c to remove the
dependency on CONFIG_BLOCK.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Fred Isaman <iisaman@netapp.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Keep track of the number of bytes read or written via buffered, direct, and
mem-mapped i/o for use by mdsthreshold size_io hints.
Signed-off-by: NAndy Adamson <andros@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>
Cc: Fred Isaman <iisaman@netapp.com>

Function rename to ensure that the functionality of nfs_unlock_request()
mirrors that of nfs_lock_request(). Then let nfs_unlock_and_release_request()
do the work of what used to be called nfs_unlock_request()...
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>
Cc: Fred Isaman <iisaman@netapp.com>

We only have two places where we need to grab a reference when trying
to lock the nfs_page. We're better off making that explicit.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>
Cc: Fred Isaman <iisaman@netapp.com>

Fix the following sparse warnings:

fs/nfs/direct.c:221:6: warning: symbol 'nfs_direct_readpage_release' was
not declared. Should it be static?
fs/nfs/read.c:38:43: warning: non-ANSI function declaration of function
'nfs_readhdr_alloc'
fs/nfs/objlayout/objio_osd.c:214:5: warning: symbol '__alloc_objio_seg'
was not declared. Should it be static?
Reported-by: NDan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>
Cc: Fred Isaman <iisaman@netapp.com>
Cc: Boaz Harrosh <bharrosh@panasas.com>

Fix the following compile warnings:
fs/nfs/direct.c: In function 'nfs_direct_read_schedule_segment':
fs/nfs/direct.c:325:11: warning: comparison of distinct pointer types
lacks a cast [enabled by default]
fs/nfs/direct.c:325:11: warning: comparison of distinct pointer types
lacks a cast [enabled by default]
fs/nfs/direct.c:325:11: warning: comparison of distinct pointer types
lacks a cast [enabled by default]
fs/nfs/direct.c:352:27: warning: comparison of distinct pointer types
lacks a cast [enabled by default]
fs/nfs/direct.c: In function 'nfs_direct_write_schedule_segment':
fs/nfs/direct.c:622:11: warning: comparison of distinct pointer types
lacks a cast [enabled by default]
fs/nfs/direct.c:622:11: warning: comparison of distinct pointer types
lacks a cast [enabled by default]
fs/nfs/direct.c:622:11: warning: comparison of distinct pointer types
lacks a cast [enabled by default]
fs/nfs/direct.c:650:27: warning: comparison of distinct pointer types
lacks a cast [enabled by default]
Reported-by: NStephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>
Cc: Fred Isaman <iisaman@netapp.com>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>

Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>
Cc: Fred Isaman <iisaman@netapp.com>

Simplify the initialisation of O_DIRECT requests.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>
Cc: Fred Isaman <iisaman@netapp.com>

The O_DIRECT code shouldn't need to hold 2 references to each page. The
reference held by the struct nfs_page should suffice.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>
Cc: Fred Isaman <iisaman@netapp.com>

Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>
Cc: Fred Isaman <iisaman@netapp.com>

Currently we do break out of the for() loop, but we also need to
break out of the enclosing do {} while()...
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>
Cc: Fred Isaman <iisaman@netapp.com>

v2 doesn't have commits, so this function can be a no-op.
Signed-off-by: NBryan Schumaker <bjschuma@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

This also has the advantage that it allows directio to use pnfs.
Signed-off-by: NFred Isaman <iisaman@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

This also has the advantage that it allows directio to use pnfs.
Signed-off-by: NFred Isaman <iisaman@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Decouple nfs_pgio_header and nfs_write_data, and have (possibly
multiple) nfs_write_datas each take a refcount on nfs_pgio_header.

For the moment keeps nfs_write_header as a way to preallocate a single
nfs_write_data with the nfs_pgio_header.  The code doesn't need this,
and would be prettier without, but given the amount of churn I am
already introducing I didn't want to play with tuning new mempools.

This also fixes bug in pnfs_ld_handle_write_error.  In the case of
desc->pg_bsize < PAGE_CACHE_SIZE, the pages list was empty, causing
replay attempt to do nothing.
Signed-off-by: NFred Isaman <iisaman@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Decouple nfs_pgio_header and nfs_read_data, and have (possibly
multiple) nfs_read_datas each take a refcount on nfs_pgio_header.

For the moment keeps nfs_read_header as a way to preallocate a single
nfs_read_data with the nfs_pgio_header.  The code doesn't need this,
and would be prettier without, but given the amount of churn I am
already introducing I didn't want to play with tuning new mempools.

This also fixes bug in pnfs_ld_handle_read_error.  In the case of
desc->pg_bsize < PAGE_CACHE_SIZE, the pages list was empty, causing
replay attempt to do nothing.
Signed-off-by: NFred Isaman <iisaman@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Both nfs_read_data and nfs_write_data devote several fields which
can be combined into a single shared struct.
Signed-off-by: NFred Isaman <iisaman@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

In order to avoid duplicating all the data in nfs_read_data whenever we
split it up into multiple RPC calls (either due to a short read result
or due to rsize < PAGE_SIZE), we split out the bits that are the same
per RPC call into a separate "header" structure.

The goal this patch moves towards is to have a single header
refcounted by several rpc_data structures.  Thus, want to always refer
from rpc_data to the header, and not the other way.  This patch comes
close to that ideal, but the directio code currently needs some
special casing, isolated in the nfs_direct_[read_write]hdr_release()
functions.  This will be dealt with in a future patch.
Signed-off-by: NFred Isaman <iisaman@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Signed-off-by: NFred Isaman <iisaman@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Commits don't need the vectors of pages, etc. that writes do. Split out
a separate structure for the commit operation.
Signed-off-by: NFred Isaman <iisaman@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Signed-off-by: NFred Isaman <iisaman@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Remove all #inclusions of asm/system.h preparatory to splitting and killing
it.  Performed with the following command:

perl -p -i -e 's!^#\s*include\s*<asm/system[.]h>.*\n!!' `grep -Irl '^#\s*include\s*<asm/system[.]h>' *`
Signed-off-by: NDavid Howells <dhowells@redhat.com>

This is an NFS v4 specific operation, so it belongs in the NFS v4 code
and not the generic client.
Signed-off-by: NBryan Schumaker <bjschuma@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

This is an NFS v4 specific operation, so it belongs in the NFS v4 code
and not the generic client.
Signed-off-by: NBryan Schumaker <bjschuma@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

This allows us to move duplicated code in <asm/atomic.h>
(atomic_inc_not_zero() for now) to <linux/atomic.h>
Signed-off-by: NArun Sharma <asharma@fb.com>
Reviewed-by: NEric Dumazet <eric.dumazet@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: David Miller <davem@davemloft.net>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Acked-by: NMike Frysinger <vapier@gentoo.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

just dentry, please...
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Account NFS direct-io reads and writes into Task I/O Accounting.
Do it before complition to handle aio.

NFS have unusual direct-io implementation,
thus accounting in generic code does not work.
Signed-off-by: NKonstantin Khlebnikov <khlebnikov@openvz.org>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

The code was doing nothing more in either branch of the if.
Signed-off-by: NFred Isaman <iisaman@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Nick Piggin reports:

> I'm getting use after frees in aio code in NFS
>
> [ 2703.396766] Call Trace:
> [ 2703.396858]  [<ffffffff8100b057>] ? native_sched_clock+0x27/0x80
> [ 2703.396959]  [<ffffffff8108509e>] ? put_lock_stats+0xe/0x40
> [ 2703.397058]  [<ffffffff81088348>] ? lock_release_holdtime+0xa8/0x140
> [ 2703.397159]  [<ffffffff8108a2a5>] lock_acquire+0x95/0x1b0
> [ 2703.397260]  [<ffffffff811627db>] ? aio_put_req+0x2b/0x60
> [ 2703.397361]  [<ffffffff81039701>] ? get_parent_ip+0x11/0x50
> [ 2703.397464]  [<ffffffff81612a31>] _raw_spin_lock_irq+0x41/0x80
> [ 2703.397564]  [<ffffffff811627db>] ? aio_put_req+0x2b/0x60
> [ 2703.397662]  [<ffffffff811627db>] aio_put_req+0x2b/0x60
> [ 2703.397761]  [<ffffffff811647fe>] do_io_submit+0x2be/0x7c0
> [ 2703.397895]  [<ffffffff81164d0b>] sys_io_submit+0xb/0x10
> [ 2703.397995]  [<ffffffff8100307b>] system_call_fastpath+0x16/0x1b
>
> Adding some tracing, it is due to nfs completing the request then
> returning something other than -EIOCBQUEUED, so aio.c
> also completes the request.

To address this, prevent the NFS direct I/O engine from completing
async iocbs when the forward path returns an error without starting
any I/O.

This fix appears to survive ^C during both "xfstest no. 208" and "fsx
-Z."

It's likely this bug has existed for a very long while, as we are seeing
very similar symptoms in OEL 5.  Copying stable.

Cc: Stable <stable@kernel.org>
Signed-off-by: NChuck Lever <chuck.lever@oracle.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

When an application opens a file with O_DIRECT flag, if the size of
the data that is written is equal to wsize, the client sends a
WRITE RPC with stable flag set to UNSTABLE followed by a single
COMMIT RPC rather than sending a single WRITE RPC with the stable
flag set to FILE_SYNC. This a bug.

Patch to fix this.
Signed-off-by: NArun R Bharadwaj <arun@linux.vnet.ibm.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

A typo, introduced by commit f11ac8db, in the nfs_direct_write()
routine causes writes with O_DIRECT set to fail with a ENOMEM error.
Found-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NSteve Dickson <steved@redhat.com>
Cc: stable@kernel.org
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

This patch fixes bugzilla entry 14501:
  https://bugzilla.kernel.org/show_bug.cgi?id=14501Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h

percpu.h is included by sched.h and module.h and thus ends up being
included when building most .c files.  percpu.h includes slab.h which
in turn includes gfp.h making everything defined by the two files
universally available and complicating inclusion dependencies.

percpu.h -> slab.h dependency is about to be removed.  Prepare for
this change by updating users of gfp and slab facilities include those
headers directly instead of assuming availability.  As this conversion
needs to touch large number of source files, the following script is
used as the basis of conversion.

  http://userweb.kernel.org/~tj/misc/slabh-sweep.py

The script does the followings.

* Scan files for gfp and slab usages and update includes such that
  only the necessary includes are there.  ie. if only gfp is used,
  gfp.h, if slab is used, slab.h.

* When the script inserts a new include, it looks at the include
  blocks and try to put the new include such that its order conforms
  to its surrounding.  It's put in the include block which contains
  core kernel includes, in the same order that the rest are ordered -
  alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
  doesn't seem to be any matching order.

* If the script can't find a place to put a new include (mostly
  because the file doesn't have fitting include block), it prints out
  an error message indicating which .h file needs to be added to the
  file.

The conversion was done in the following steps.

1. The initial automatic conversion of all .c files updated slightly
   over 4000 files, deleting around 700 includes and adding ~480 gfp.h
   and ~3000 slab.h inclusions.  The script emitted errors for ~400
   files.

2. Each error was manually checked.  Some didn't need the inclusion,
   some needed manual addition while adding it to implementation .h or
   embedding .c file was more appropriate for others.  This step added
   inclusions to around 150 files.

3. The script was run again and the output was compared to the edits
   from #2 to make sure no file was left behind.

4. Several build tests were done and a couple of problems were fixed.
   e.g. lib/decompress_*.c used malloc/free() wrappers around slab
   APIs requiring slab.h to be added manually.

5. The script was run on all .h files but without automatically
   editing them as sprinkling gfp.h and slab.h inclusions around .h
   files could easily lead to inclusion dependency hell.  Most gfp.h
   inclusion directives were ignored as stuff from gfp.h was usually
   wildly available and often used in preprocessor macros.  Each
   slab.h inclusion directive was examined and added manually as
   necessary.

6. percpu.h was updated not to include slab.h.

7. Build test were done on the following configurations and failures
   were fixed.  CONFIG_GCOV_KERNEL was turned off for all tests (as my
   distributed build env didn't work with gcov compiles) and a few
   more options had to be turned off depending on archs to make things
   build (like ipr on powerpc/64 which failed due to missing writeq).

   * x86 and x86_64 UP and SMP allmodconfig and a custom test config.
   * powerpc and powerpc64 SMP allmodconfig
   * sparc and sparc64 SMP allmodconfig
   * ia64 SMP allmodconfig
   * s390 SMP allmodconfig
   * alpha SMP allmodconfig
   * um on x86_64 SMP allmodconfig

8. percpu.h modifications were reverted so that it could be applied as
   a separate patch and serve as bisection point.

Given the fact that I had only a couple of failures from tests on step
6, I'm fairly confident about the coverage of this conversion patch.
If there is a breakage, it's likely to be something in one of the arch
headers which should be easily discoverable easily on most builds of
the specific arch.
Signed-off-by: NTejun Heo <tj@kernel.org>
Guess-its-ok-by: NChristoph Lameter <cl@linux-foundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>