nfs4_lookup_revalidate only uses 'parent' to get 'dir', and only
uses 'dir' if 'inode == NULL'.

So we don't need to find out what 'parent' or 'dir' is until we
know that 'inode' is NULL.

By moving 'dget_parent' inside the 'if', we can reduce the number of
call sites for 'dput(parent)'.
Signed-off-by: NNeilBrown <neilb@suse.de>
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

This may be used to limit the number of cached credentials building up
inside the access cache.
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

Mostly scripted conversion of the smp_mb__* barriers.
Signed-off-by: NPeter Zijlstra <peterz@infradead.org>
Acked-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com>
Link: http://lkml.kernel.org/n/tip-55dhyhocezdw1dg7u19hmh1u@git.kernel.org
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: linux-arch@vger.kernel.org
Signed-off-by: NIngo Molnar <mingo@kernel.org>

There is no guarantee that the strings in the nfs_cache_array will be
NULL-terminated. In the event that we end up hitting a readdir loop, we
need to ensure that we pass the warning message the length of the
string.
Reported-by: NLachlan McIlroy <lmcilroy@redhat.com>
Signed-off-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

There isn't much sense in maintaining two separate versions of rename
code. Convert nfs_rename to use the asynchronous rename infrastructure
that nfs_sillyrename uses, and emulate synchronous behavior by having
the task just wait on the reply.
Signed-off-by: NJeff Layton <jlayton@redhat.com>
Tested-by: NAnna Schumaker <Anna.Schumaker@netapp.com>
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

Try to detect 'ls -l' by having nfs_getattr() look at whether or not
there is an opendir() file descriptor for the parent directory.
If so, then assume that we want to force use of readdirplus in order
to avoid the multiple GETATTR calls over the wire.
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

Changes in commit a0b8cab3 ("mm: remove lru parameter from
__pagevec_lru_add and remove parts of pagevec API") have introduced a
call to add_to_page_cache_lru() which causes a leak in nfs_symlink() as
now the page gets an extra refcount that is not dropped.

Jan Stancek observed and reported the leak effect while running test8
from Connectathon Testsuite.  After several iterations over the test
case, which creates several symlinks on a NFS mountpoint, the test
system was quickly getting into an out-of-memory scenario.

This patch fixes the page leak by dropping that extra refcount
add_to_page_cache_lru() is grabbing.
Signed-off-by: NJan Stancek <jstancek@redhat.com>
Signed-off-by: NRafael Aquini <aquini@redhat.com>
Acked-by: NMel Gorman <mgorman@suse.de>
Acked-by: NRik van Riel <riel@redhat.com>
Cc: Jeff Layton <jlayton@redhat.com>
Cc: Trond Myklebust <trond.myklebust@primarydata.com>
Cc: <stable@vger.kernel.org>	[3.11.x+]
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

If the setting of NFS_INO_INVALIDATING gets reordered to before the
clearing of NFS_INO_INVALID_DATA, then another task may hit a race
window where both appear to be clear, even though the inode's pages are
still in need of invalidation. Fix this by adding the appropriate memory
barriers.
Signed-off-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

There is a possible race in how the nfs_invalidate_mapping function is
handled.  Currently, we go and invalidate the pages in the file and then
clear NFS_INO_INVALID_DATA.

The problem is that it's possible for a stale page to creep into the
mapping after the page was invalidated (i.e., via readahead). If another
writer comes along and sets the flag after that happens but before
invalidate_inode_pages2 returns then we could clear the flag
without the cache having been properly invalidated.

So, we must clear the flag first and then invalidate the pages. Doing
this however, opens another race:

It's possible to have two concurrent read() calls that end up in
nfs_revalidate_mapping at the same time. The first one clears the
NFS_INO_INVALID_DATA flag and then goes to call nfs_invalidate_mapping.

Just before calling that though, the other task races in, checks the
flag and finds it cleared. At that point, it trusts that the mapping is
good and gets the lock on the page, allowing the read() to be satisfied
from the cache even though the data is no longer valid.

These effects are easily manifested by running diotest3 from the LTP
test suite on NFS. That program does a series of DIO writes and buffered
reads. The operations are serialized and page-aligned but the existing
code fails the test since it occasionally allows a read to come out of
the cache incorrectly. While mixing direct and buffered I/O isn't
recommended, I believe it's possible to hit this in other ways that just
use buffered I/O, though that situation is much harder to reproduce.

The problem is that the checking/clearing of that flag and the
invalidation of the mapping really need to be atomic. Fix this by
serializing concurrent invalidations with a bitlock.

At the same time, we also need to allow other places that check
NFS_INO_INVALID_DATA to check whether we might be in the middle of
invalidating the file, so fix up a couple of places that do that
to look for the new NFS_INO_INVALIDATING flag.

Doing this requires us to be careful not to set the bitlock
unnecessarily, so this code only does that if it believes it will
be doing an invalidation.
Signed-off-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

A fileid in NFS is a uint64. There are some occurrences where dprintk()
outputs a signed fileid. This leads to confusion and more difficult to
read debugging (negative fileids matching positive inode numbers).
Signed-off-by: NNiels de Vos <ndevos@redhat.com>
CC: Santosh Pradhan <spradhan@redhat.com>
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

This check was added by Al Viro with
d9e80b7d "nfs d_revalidate() is too
trigger-happy with d_drop()", with the explanation that we don't want to
remove the root of a disconnected tree, which will still be included on
the s_anon list.

But DCACHE_DISCONNECTED does *not* actually identify dentries that are
disconnected from the dentry tree or hashed on s_anon.  IS_ROOT() is the
way to do that.

Also add a comment from Al's commit to remind us why this check is
there.
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

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

Use i_writecount to control whether to get an fscache cookie in nfs_open() as
NFS does not do write caching yet.  I *think* this is the cause of a problem
encountered by Mark Moseley whereby __fscache_uncache_page() gets a NULL
pointer dereference because cookie->def is NULL:

BUG: unable to handle kernel NULL pointer dereference at 0000000000000010
IP: [<ffffffff812a1903>] __fscache_uncache_page+0x23/0x160
PGD 0
Thread overran stack, or stack corrupted
Oops: 0000 [#1] SMP
Modules linked in: ...
CPU: 7 PID: 18993 Comm: php Not tainted 3.11.1 #1
Hardware name: Dell Inc. PowerEdge R420/072XWF, BIOS 1.3.5 08/21/2012
task: ffff8804203460c0 ti: ffff880420346640
RIP: 0010:[<ffffffff812a1903>] __fscache_uncache_page+0x23/0x160
RSP: 0018:ffff8801053af878 EFLAGS: 00210286
RAX: 0000000000000000 RBX: ffff8800be2f8780 RCX: ffff88022ffae5e8
RDX: 0000000000004c66 RSI: ffffea00055ff440 RDI: ffff8800be2f8780
RBP: ffff8801053af898 R08: 0000000000000001 R09: 0000000000000003
R10: 0000000000000000 R11: 0000000000000000 R12: ffffea00055ff440
R13: 0000000000001000 R14: ffff8800c50be538 R15: 0000000000000000
FS: 0000000000000000(0000) GS:ffff88042fc60000(0063) knlGS:00000000e439c700
CS: 0010 DS: 002b ES: 002b CR0: 0000000080050033
CR2: 0000000000000010 CR3: 0000000001d8f000 CR4: 00000000000607f0
Stack:
...
Call Trace:
[<ffffffff81365a72>] __nfs_fscache_invalidate_page+0x42/0x70
[<ffffffff813553d5>] nfs_invalidate_page+0x75/0x90
[<ffffffff811b8f5e>] truncate_inode_page+0x8e/0x90
[<ffffffff811b90ad>] truncate_inode_pages_range.part.12+0x14d/0x620
[<ffffffff81d6387d>] ? __mutex_lock_slowpath+0x1fd/0x2e0
[<ffffffff811b95d3>] truncate_inode_pages_range+0x53/0x70
[<ffffffff811b969d>] truncate_inode_pages+0x2d/0x40
[<ffffffff811b96ff>] truncate_pagecache+0x4f/0x70
[<ffffffff81356840>] nfs_setattr_update_inode+0xa0/0x120
[<ffffffff81368de4>] nfs3_proc_setattr+0xc4/0xe0
[<ffffffff81357f78>] nfs_setattr+0xc8/0x150
[<ffffffff8122d95b>] notify_change+0x1cb/0x390
[<ffffffff8120a55b>] do_truncate+0x7b/0xc0
[<ffffffff8121f96c>] do_last+0xa4c/0xfd0
[<ffffffff8121ffbc>] path_openat+0xcc/0x670
[<ffffffff81220a0e>] do_filp_open+0x4e/0xb0
[<ffffffff8120ba1f>] do_sys_open+0x13f/0x2b0
[<ffffffff8126aaf6>] compat_SyS_open+0x36/0x50
[<ffffffff81d7204c>] sysenter_dispatch+0x7/0x24

The code at the instruction pointer was disassembled:

> (gdb) disas __fscache_uncache_page
> Dump of assembler code for function __fscache_uncache_page:
> ...
> 0xffffffff812a18ff <+31>: mov 0x48(%rbx),%rax
> 0xffffffff812a1903 <+35>: cmpb $0x0,0x10(%rax)
> 0xffffffff812a1907 <+39>: je 0xffffffff812a19cd <__fscache_uncache_page+237>

These instructions make up:

	ASSERTCMP(cookie->def->type, !=, FSCACHE_COOKIE_TYPE_INDEX);

That cmpb is the faulting instruction (%rax is 0).  So cookie->def is NULL -
which presumably means that the cookie has already been at least partway
through __fscache_relinquish_cookie().

What I think may be happening is something like a three-way race on the same
file:

	PROCESS 1	PROCESS 2	PROCESS 3
	===============	===============	===============
	open(O_TRUNC|O_WRONLY)
			open(O_RDONLY)
					open(O_WRONLY)
	-->nfs_open()
	-->nfs_fscache_set_inode_cookie()
	nfs_fscache_inode_lock()
	nfs_fscache_disable_inode_cookie()
	__fscache_relinquish_cookie()
	nfs_inode->fscache = NULL
	<--nfs_fscache_set_inode_cookie()

			-->nfs_open()
			-->nfs_fscache_set_inode_cookie()
			nfs_fscache_inode_lock()
			nfs_fscache_enable_inode_cookie()
			__fscache_acquire_cookie()
			nfs_inode->fscache = cookie
			<--nfs_fscache_set_inode_cookie()
	<--nfs_open()
	-->nfs_setattr()
	...
	...
	-->nfs_invalidate_page()
	-->__nfs_fscache_invalidate_page()
	cookie = nfsi->fscache
					-->nfs_open()
					-->nfs_fscache_set_inode_cookie()
					nfs_fscache_inode_lock()
					nfs_fscache_disable_inode_cookie()
					-->__fscache_relinquish_cookie()
	-->__fscache_uncache_page(cookie)
	<crash>
					<--__fscache_relinquish_cookie()
					nfs_inode->fscache = NULL
					<--nfs_fscache_set_inode_cookie()

What is needed is something to prevent process #2 from reacquiring the cookie
- and I think checking i_writecount should do the trick.

It's also possible to have a two-way race on this if the file is opened
O_TRUNC|O_RDONLY instead.
Reported-by: NMark Moseley <moseleymark@gmail.com>
Signed-off-by: NDavid Howells <dhowells@redhat.com>

Determine if we've created a new file by examining the directory change
attribute and/or the O_EXCL flag.

This fixes a regression when doing a non-exclusive create of a new file.
If the FILE_CREATED flag is not set, the atomic_open() command will
perform full file access permissions checks instead of just checking
for MAY_OPEN.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Set FILE_CREATED on O_CREAT|O_EXCL.  If the NFS server honored our request
for exclusivity then this must be correct.

Currently this is a no-op, since the VFS sets FILE_CREATED anyway.  The
next patch will, however, require this flag to be always set by
filesystems.
Signed-off-by: NMiklos Szeredi <mszeredi@suse.cz>
Cc: Trond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Convert the filesystem shrinkers to use the new API, and standardise some
of the behaviours of the shrinkers at the same time.  For example,
nr_to_scan means the number of objects to scan, not the number of objects
to free.

I refactored the CIFS idmap shrinker a little - it really needs to be
broken up into a shrinker per tree and keep an item count with the tree
root so that we don't need to walk the tree every time the shrinker needs
to count the number of objects in the tree (i.e.  all the time under
memory pressure).

[glommer@openvz.org: fixes for ext4, ubifs, nfs, cifs and glock. Fixes are needed mainly due to new code merged in the tree]
[assorted fixes folded in]
Signed-off-by: NDave Chinner <dchinner@redhat.com>
Signed-off-by: NGlauber Costa <glommer@openvz.org>
Acked-by: NMel Gorman <mgorman@suse.de>
Acked-by: NArtem Bityutskiy <artem.bityutskiy@linux.intel.com>
Acked-by: NJan Kara <jack@suse.cz>
Acked-by: NSteven Whitehouse <swhiteho@redhat.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: "Theodore Ts'o" <tytso@mit.edu>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Cc: Arve Hjønnevåg <arve@android.com>
Cc: Carlos Maiolino <cmaiolino@redhat.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Chuck Lever <chuck.lever@oracle.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: David Rientjes <rientjes@google.com>
Cc: Gleb Natapov <gleb@redhat.com>
Cc: Greg Thelen <gthelen@google.com>
Cc: J. Bruce Fields <bfields@redhat.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Jerome Glisse <jglisse@redhat.com>
Cc: John Stultz <john.stultz@linaro.org>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Kent Overstreet <koverstreet@google.com>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Steven Whitehouse <swhiteho@redhat.com>
Cc: Thomas Hellstrom <thellstrom@vmware.com>
Cc: Trond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

The sysctl knob sysctl_vfs_cache_pressure is used to determine which
percentage of the shrinkable objects in our cache we should actively try
to shrink.

It works great in situations in which we have many objects (at least more
than 100), because the aproximation errors will be negligible.  But if
this is not the case, specially when total_objects < 100, we may end up
concluding that we have no objects at all (total / 100 = 0, if total <
100).

This is certainly not the biggest killer in the world, but may matter in
very low kernel memory situations.
Signed-off-by: NGlauber Costa <glommer@openvz.org>
Reviewed-by: NCarlos Maiolino <cmaiolino@redhat.com>
Acked-by: NKAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Acked-by: NMel Gorman <mgorman@suse.de>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: "Theodore Ts'o" <tytso@mit.edu>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Cc: Arve Hjønnevåg <arve@android.com>
Cc: Carlos Maiolino <cmaiolino@redhat.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Chuck Lever <chuck.lever@oracle.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: David Rientjes <rientjes@google.com>
Cc: Gleb Natapov <gleb@redhat.com>
Cc: Greg Thelen <gthelen@google.com>
Cc: J. Bruce Fields <bfields@redhat.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Jerome Glisse <jglisse@redhat.com>
Cc: John Stultz <john.stultz@linaro.org>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Kent Overstreet <koverstreet@google.com>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Steven Whitehouse <swhiteho@redhat.com>
Cc: Thomas Hellstrom <thellstrom@vmware.com>
Cc: Trond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Do have_submounts(), shrink_dcache_parent() and d_drop() atomically.

check_submounts_and_drop() can deal with negative dentries and
non-directories as well.

Non-directories can also be mounted on.  And just like directories we don't
want these to disappear with invalidation.
Signed-off-by: NMiklos Szeredi <mszeredi@suse.cz>
CC: Trond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

If an NFS client does

	mkdir("dir");
	fd = open("dir/file");
	unlink("dir/file");
	close(fd);
	rmdir("dir");

then the asynchronous nature of the sillyrename operation means that
we can end up getting EBUSY for the rmdir() in the above test. Fix
that by ensuring that we wait for any in-progress sillyrenames
before sending the rmdir() to the server.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

We don't want to pass the context argument to trace_nfs_atomic_open_exit()
after it has been released.
Reported-by: NDan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

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

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

Add tracepoints for mknod, mkdir, rmdir, remove (unlink) and symlink.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

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

Add tracepoints for lookup, lookup_revalidate and atomic_open
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

When doing an open of a directory, ensure that we do pass the lookup flags
from nfs_atomic_open into nfs_lookup.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Add tracepoints for inode attribute updates, attribute revalidation,
writeback start/end fsync start/end, attribute change start/end,
permission check start/end.

The intention is to enable performance tracing using 'perf'as well as
improving debugging.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Ever since commit 6168f62c (Add ACCESS operation to OPEN compound)
the NFSv4 atomic open has primed the access cache, and so nfs_permission
will no longer do an RPC call on the wire.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Currently, you can open a NFSv4 file with O_APPEND|O_DIRECT, but cannot
fcntl(F_SETFL,...) with those flags. This flag combination is explicitly
forbidden on NFSv3 opens, and it seems like it should also be on NFSv4.
Reported-by: NChao Ye <cye@redhat.com>
Signed-off-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Make nfs_readdir revalidate only when we're at the beginning of the directory or
if the cached attributes have expired.
Signed-off-by: NScott Mayhew <smayhew@redhat.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

nfs_prime_dcache currently only sets the verifier when it doesn't
initially a matching dentry in the dcache. Set the verifier in the case
where we do find a dentry in the dcache. This ensures that we don't
have to look up the dentry again if we want to use it after a readdir.

Cc: Scott Mayhew <smayhew@redhat.com>
Signed-off-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

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

Now that the LRU to add a page to is decided at LRU-add time, remove the
misleading lru parameter from __pagevec_lru_add.  A consequence of this
is that the pagevec_lru_add_file, pagevec_lru_add_anon and similar
helpers are misleading as the caller no longer has direct control over
what LRU the page is added to.  Unused helpers are removed by this patch
and existing users of pagevec_lru_add_file() are converted to use
lru_cache_add_file() directly and use the per-cpu pagevecs instead of
creating their own pagevec.
Signed-off-by: NMel Gorman <mgorman@suse.de>
Reviewed-by: NJan Kara <jack@suse.cz>
Reviewed-by: NRik van Riel <riel@redhat.com>
Acked-by: NJohannes Weiner <hannes@cmpxchg.org>
Cc: Alexey Lyahkov <alexey.lyashkov@gmail.com>
Cc: Andrew Perepechko <anserper@ya.ru>
Cc: Robin Dong <sanbai@taobao.com>
Cc: Theodore Tso <tytso@mit.edu>
Cc: Hugh Dickins <hughd@google.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Bernd Schubert <bernd.schubert@fastmail.fm>
Cc: David Howells <dhowells@redhat.com>
Cc: Trond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

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

This patch implements the client transport and handling support for labeled
NFS. The patch adds two functions to encode and decode the security label
recommended attribute which makes use of the LSM hooks added earlier. It also
adds code to grab the label from the file attribute structures and encode the
label to be sent back to the server.
Acked-by: NJames Morris <james.l.morris@oracle.com>
Signed-off-by: NMatthew N. Dodd <Matthew.Dodd@sparta.com>
Signed-off-by: NMiguel Rodel Felipe <Rodel_FM@dsi.a-star.edu.sg>
Signed-off-by: NPhua Eu Gene <PHUA_Eu_Gene@dsi.a-star.edu.sg>
Signed-off-by: NKhin Mi Mi Aung <Mi_Mi_AUNG@dsi.a-star.edu.sg>
Signed-off-by: NSteve Dickson <steved@redhat.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

This patch adds the lifecycle management for the security label structure
introduced in an earlier patch. The label is not used yet but allocations and
freeing of the structure is handled.
Signed-off-by: NMatthew N. Dodd <Matthew.Dodd@sparta.com>
Signed-off-by: NMiguel Rodel Felipe <Rodel_FM@dsi.a-star.edu.sg>
Signed-off-by: NPhua Eu Gene <PHUA_Eu_Gene@dsi.a-star.edu.sg>
Signed-off-by: NKhin Mi Mi Aung <Mi_Mi_AUNG@dsi.a-star.edu.sg>
Signed-off-by: NSteve Dickson <steved@redhat.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

After looking at all of the nfsv4 operations the label structure has been added
to the prototypes of the functions which can transmit label data.
Signed-off-by: NMatthew N. Dodd <Matthew.Dodd@sparta.com>
Signed-off-by: NMiguel Rodel Felipe <Rodel_FM@dsi.a-star.edu.sg>
Signed-off-by: NPhua Eu Gene <PHUA_Eu_Gene@dsi.a-star.edu.sg>
Signed-off-by: NKhin Mi Mi Aung <Mi_Mi_AUNG@dsi.a-star.edu.sg>
Signed-off-by: NSteve Dickson <steved@redhat.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

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

We already check the EXEC access mode in the lower layers.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Sometimes, we actually _want_ to do open-by-filehandle, for instance
when recovering opens after a network partition, or when called
from nfs4_file_open.
Enable that functionality using a new capability NFS_CAP_ATOMIC_OPEN_V1,
and which is only enabled for NFSv4.1 servers that support it.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>