This code is run under lock_kernel(), which is dropped during
sleeping operations, so the following race is possible:

CPU1:                                CPU2:
  vfs_setlease();                    vfs_setlease();
  lock_kernel();
                                     lock_kernel(); /* spin */
  generic_setlease():
    ...
    for (before = ...)
    /* here we found some lease after
     * which we will insert the new one
     */
    fl = locks_alloc_lock();
    /* go to sleep in this allocation and
     * drop the BKL
     */
                                     generic_setlease():
                                       ...
                                       for (before = ...)
                                       /* here we find the "before" pointing
                                        * at the one we found on CPU1
                                        */
                                      ->fl_change(my_before, arg);
                                              lease_modify();
                                                     locks_free_lock();
                                                     /* and we freed it */
                                     ...
                                     unlock_kernel();
   locks_insert_lock(before, fl);
   /* OOPS! We have just tried to add the lease
    * at the tail of already removed one
    */

The similar races are already handled in other code - all the
allocations are performed before any checks/updates.

Thanks to Kamalesh Babulal for testing and for a bug report on an
earlier version.
Signed-off-by: NPavel Emelyanov <xemul@openvz.org>
Signed-off-by: NJ. Bruce Fields <bfields@citi.umich.edu>
Cc: Kamalesh Babulal <kamalesh@linux.vnet.ibm.com>

This routine deletes all the elements from the list
with the "while (!list_empty())" loop, and we already
have a list_first_entry() macro to help it look nicer :)
Signed-off-by: NPavel Emelyanov <xemul@openvz.org>

This comment wasn't updated when lease support was added, and it makes
essentially the same mistake that the code made before a recent bugfix.
Signed-off-by: NJ. Bruce Fields <bfields@citi.umich.edu>

When the flock_lock_file() is called to change the flock
from F_RDLCK to F_WRLCK or vice versa the existing flock
can be removed without appropriate warning.

Look:
        for_each_lock(inode, before) {
                struct file_lock *fl = *before;
                if (IS_POSIX(fl))
                        break;
                if (IS_LEASE(fl))
                        continue;
                if (filp != fl->fl_file)
                        continue;
                if (request->fl_type == fl->fl_type)
                        goto out;
                found = 1;
                locks_delete_lock(before); <<<<<< !
                break;
        }

if after this point the subsequent locks_alloc_lock() will
fail the return code will be -ENOMEM, but the existing lock
is already removed.

This is a known feature that such "re-locking" is not atomic,
but in the racy case the file should stay locked (although by
some other process), but in this case the file will be unlocked.

The proposal is to prepare the lock in advance keeping no chance
to fail in the future code.

Found during making the flocks pid-namespaces aware.

(Note: Thanks to Reuben Farrelly for finding a bug in an earlier version
of this patch.)
Signed-off-by: NPavel Emelyanov <xemul@openvz.org>
Signed-off-by: NJ. Bruce Fields <bfields@citi.umich.edu>
Cc: Reuben Farrelly <reuben-linuxkernel@reub.net>

There's no need for another variable local to this loop; we can use the
variable (of the same name!) already declared at the top of the function,
and not used till later (at which point it's initialized, so this is safe).
Signed-off-by: NJ. Bruce Fields <bfields@citi.umich.edu>

The first argument to posix_locks_conflict() is meant to be a lock request,
and the second a lock from an inode's lock request.  It doesn't really
make a difference which order you call them in, since the only
asymmetric test in posix_lock_conflict() is the check whether the second
argument is a posix lock--and every caller already does that check for
some reason.

But may as well fix posix_test_lock() to call posix_locks_conflict()
with the arguments in the same order as everywhere else.
Signed-off-by: N"J. Bruce Fields" <bfields@citi.umich.edu>

The recent fix for a circular lock dependency unfortunately introduced a
potential memory leak in the event where the call to nlmsvc_lookup_host
fails for some reason.

Thanks to Roel Kluin for spotting this.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

When IOCB_FLAG_RESFD flag is set and iocb->aio_resfd is incorrect,
statement 'goto out_put_req' is executed. At label 'out_put_req',
aio_put_req(..) is called, which requires 'req->ki_filp' set.

Signed-off-by: Yan Zheng<yanzheng@21cn.com>
Cc: Zach Brown <zach.brown@oracle.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The fs was not unlocking the local alloc inode mutex in the code path in
which it failed to find a window of free bits in the global bitmap.
Signed-off-by: NSunil Mushran <sunil.mushran@oracle.com>
Signed-off-by: NMark Fasheh <mark.fasheh@oracle.com>

Nick Piggin points out that splice isn't being good about the mmap
semaphore: while two readers can nest inside each others, it does leave
a possible deadlock if a writer (ie a new mmap()) comes in during that
nesting.

Original "just move the locking" patch by Nick, replaced by one by me
based on an optimistic pagefault_disable().  And then Jens tested and
updated that patch.
Reported-by: NNick Piggin <npiggin@suse.de>
Tested-by: NJens Axboe <jens.axboe@oracle.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This reverts commit b394e43e.

Lachlan McIlroy says:
    It tried to fix an issue where log replay is replaying an inode cluster
    initialisation transaction that should not be replayed because the inode
    cluster on disk is more up to date.  Since we don't log file sizes (we
    rely on inode flushing to get them to disk) then we can't just replay
    all the transations in the log and expect the inode to be completely
    restored.  We lose file size updates.  Unfortunately this fix is causing
    more (serious) problems than it is fixing.

SGI-PV: 969656
SGI-Modid: xfs-linux-melb:xfs-kern:29804a
Signed-off-by: NLachlan McIlroy <lachlan@sgi.com>
Signed-off-by: NTim Shimmin <tes@sgi.com>

It doesn't look as if the NFS file name limit is being initialised correctly
in the struct nfs_server. Make sure that we limit whatever is being set in
nfs_probe_fsinfo() and nfs_init_server().

Also ensure that readdirplus and nfs4_path_walk respect our file name
limits.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The problem is that the garbage collector for the 'host' structures
nlm_gc_hosts(), holds nlm_host_mutex while calling down to
nlmsvc_mark_resources, which, eventually takes the file->f_mutex.

We cannot therefore call nlmsvc_lookup_host() from within
nlmsvc_create_block, since the caller will already hold file->f_mutex, so
the attempt to grab nlm_host_mutex may deadlock.

Fix the problem by calling nlmsvc_lookup_host() outside the file->f_mutex.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Different types of ufs hold state in different places, to hide complexity
of this, there is ufs_get_fs_state, it returns state according to
"UFS_SB(sb)->s_flags", but during mount ufs_get_fs_state is called, before
setting s_flags, this cause message for ufs types like sun ufs: "fs need
fsck", and remount in readonly state.
Signed-off-by: NEvgeniy Dushistov <dushistov@mail.ru>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Cc: Bernd Schmidt <bernd.schmidt@analog.com>
Cc: David McCullough <davidm@snapgear.com>
Cc: Greg Ungerer <gerg@snapgear.com>
Cc: Miles Bader <miles.bader@necel.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NBryan Wu <bryan.wu@analog.com>

Add minimum support for the Blackfin relocations, since we don't have
enough space in each reloc.  The idea is to store a value with one
relocation so that subsequent ones can access it.

Actually, this patch is required for Blackfin.  Currently if BINFMT_FLAT is
enabled, git-tree kernel will fail to compile.
Signed-off-by: NBernd Schmidt <bernd.schmidt@analog.com>
Signed-off-by: NBryan Wu <bryan.wu@analog.com>
Cc: David McCullough <davidm@snapgear.com>
Cc: Greg Ungerer <gerg@snapgear.com>
Cc: Miles Bader <miles.bader@necel.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>

Johannes just found that we are missing a compat-ioctl
declaration. The fix is trivial. As previous patches for compat-ioctl,
this should also go to stable.

More info :
	http://marc.info/?l=linux-wireless&m=119029667902588&w=2Signed-off-by: NJean Tourrilhes <jt@hpl.hp.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

The ocfs2_vote_msg and ocfs2_response_msg structs needed to be
packed to ensure similar sizeofs in 32-bit and 64-bit arches. Without this,
we had inadvertantly broken 32/64 bit cross mounts.
Signed-off-by: NSunil Mushran <sunil.mushran@oracle.com>
Signed-off-by: NMark Fasheh <mark.fasheh@oracle.com>

The target page offsets were being incorrectly set a second time in
ocfs2_prepare_page_for_write(), which was causing problems on a 16k page
size kernel. Additionally, ocfs2_write_failure() was incorrectly using those
parameters instead of the parameters for the individual page being cleaned
up.
Signed-off-by: NMark Fasheh <mark.fasheh@oracle.com>

This was broken for file systems whose cluster size is greater than page
size. Pos needs to be incremented as we loop through the descriptors, and
len needs to be capped to the size of a single cluster.
Signed-off-by: NMark Fasheh <mark.fasheh@oracle.com>

The ocfs2 write code loops through a page much like the block code, except
that ocfs2 allocation units can be any size, including larger than page
size. Typically it's equal to or larger than page size - most kernels run 4k
pages, the minimum ocfs2 allocation (cluster) size.

Some changes introduced during 2.6.23 changed the way writes to pages are
handled, and inadvertantly broke support for > 4k page size. Instead of just
writing one cluster at a time, we now handle the whole page in one pass.

This means that multiple (small) seperate allocations might happen in the
same pass. The allocation code howver typically optimizes by getting the
maximum which was reserved. This triggered a BUG_ON in the extend code where
it'd ask for a single bit (for one part of a > 4k page) and get back more
than it asked for.

Fix this by providing a variant of the high level allocation function which
allows the caller to specify a maximum. The traditional function remains and
just calls the new one with a maximum determined from the initial
reservation.
Signed-off-by: NMark Fasheh <mark.fasheh@oracle.com>

This simplifies signalfd code, by avoiding it to remain attached to the
sighand during its lifetime.

In this way, the signalfd remain attached to the sighand only during
poll(2) (and select and epoll) and read(2).  This also allows to remove
all the custom "tsk == current" checks in kernel/signal.c, since
dequeue_signal() will only be called by "current".

I think this is also what Ben was suggesting time ago.

The external effect of this, is that a thread can extract only its own
private signals and the group ones.  I think this is an acceptable
behaviour, in that those are the signals the thread would be able to
fetch w/out signalfd.
Signed-off-by: NDavide Libenzi <davidel@xmailserver.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The new xlog_recover_do_reg_buffer checks call be16_to_cpu on di_gen which
is a 32bit value so sparse rightly complains. Fortunately the warning is
harmless because we don't care for the value, but only whether it's
non-NULL. Due to that fact we can simply kill the endian swaps on this and
the previous di_mode check entirely.

SGI-PV: 969656
SGI-Modid: xfs-linux-melb:xfs-kern:29709a
Signed-off-by: NChristoph Hellwig <hch@infradead.org>
Signed-off-by: NLachlan McIlroy <lachlan@sgi.com>
Signed-off-by: NTim Shimmin <tes@sgi.com>

xfs_filestream_mount() sets up an mru cache with:
  err = xfs_mru_cache_create(&mp->m_filestream, lifetime, grp_count,
  (xfs_mru_cache_free_func_t)xfs_fstrm_free_func);
but that cast is causing problems...
  typedef void (*xfs_mru_cache_free_func_t)(unsigned long, void*);
but:
  void xfs_fstrm_free_func( xfs_ino_t ino, fstrm_item_t *item)
so on a 32-bit box, it's casting (32, 32) args into (64, 32) and I assume
it's getting garbage for *item, which subsequently causes an explosion.
With this change the filestreams xfsqa tests don't oops on my 32-bit box.

SGI-PV: 967795
SGI-Modid: xfs-linux-melb:xfs-kern:29510a
Signed-off-by: NEric Sandeen <sandeen@sandeen.net>
Signed-off-by: NDavid Chinner <dgc@sgi.com>
Signed-off-by: NTim Shimmin <tes@sgi.com>

The do_split() function for htree dir blocks is intended to split a leaf
block to make room for a new entry.  It sorts the entries in the original
block by hash value, then moves the last half of the entries to the new
block - without accounting for how much space this actually moves.  (IOW,
it moves half of the entry *count* not half of the entry *space*).  If by
chance we have both large & small entries, and we move only the smallest
entries, and we have a large new entry to insert, we may not have created
enough space for it.

The patch below stores each record size when calculating the dx_map, and
then walks the hash-sorted dx_map, calculating how many entries must be
moved to more evenly split the existing entries between the old block and
the new block, guaranteeing enough space for the new entry.

The dx_map "offs" member is reduced to u16 so that the overall map size
does not change - it is temporarily stored at the end of the new block, and
if it grows too large it may be overwritten.  By making offs and size both
u16, we won't grow the map size.

Also add a few comments to the functions involved.

This fixes the testcase reported by hooanon05@yahoo.co.jp on the
linux-ext4 list, "ext3 dir_index causes an error"

Thanks to Andreas Dilger for discussing the problem & solution with me.
Signed-off-by: NEric Sandeen <sandeen@redhat.com>
Signed-off-by: NAndreas Dilger <adilger@clusterfs.com>
Tested-by: NJunjiro Okajima <hooanon05@yahoo.co.jp>
Cc: Theodore Ts'o <tytso@mit.edu>
Cc: <linux-ext4@vger.kernel.org>
Cc: <stable@kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

NFS unregisters sysctls only if V4 support is compiled in.  However, sysctl
table is not V4 specific, so unregister it always.

Steps to reproduce:

	[build nfs.ko with CONFIG_NFS_V4=n]
	modrobe nfs
	rmmod nfs
	ls /proc/sys

Unable to handle kernel paging request at ffffffff880661c0 RIP:
 [<ffffffff802af8e3>] proc_sys_readdir+0xd3/0x350
PGD 203067 PUD 207063 PMD 7e216067 PTE 0
Oops: 0000 [1] SMP
CPU 1
Modules linked in: lockd nfs_acl sunrpc
Pid: 3335, comm: ls Not tainted 2.6.23-rc3-bloat #2
RIP: 0010:[<ffffffff802af8e3>]  [<ffffffff802af8e3>] proc_sys_readdir+0xd3/0x350
RSP: 0018:ffff81007fd93e78  EFLAGS: 00010286
RAX: ffffffff880661c0 RBX: ffffffff80466370 RCX: ffffffff880661c0
RDX: 00000000000014c0 RSI: ffff81007f3ad020 RDI: ffff81007efd8b40
RBP: 0000000000000018 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000001 R11: ffffffff802a8570 R12: ffffffff880661c0
R13: ffff81007e219640 R14: ffff81007efd8b40 R15: ffff81007ded7280
FS:  00002ba25ef03060(0000) GS:ffff81007ff81258(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 000000008005003b
CR2: ffffffff880661c0 CR3: 000000007dfaf000 CR4: 00000000000006e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Process ls (pid: 3335, threadinfo ffff81007fd92000, task ffff81007d8a0000)
Stack:  ffff81007f3ad150 ffffffff80283f30 ffff81007fd93f48 ffff81007efd8b40
 ffff81007ee00440 0000000422222222 0000000200035593 ffffffff88037e9a
 2222222222222222 ffffffff80466500 ffff81007e416400 ffff81007e219640
Call Trace:
 [<ffffffff80283f30>] filldir+0x0/0xf0
 [<ffffffff80283f30>] filldir+0x0/0xf0
 [<ffffffff802840c7>] vfs_readdir+0xa7/0xc0
 [<ffffffff80284376>] sys_getdents+0x96/0xe0
 [<ffffffff8020bb3e>] system_call+0x7e/0x83

Code: 41 8b 14 24 85 d2 74 dc 49 8b 44 24 08 48 85 c0 74 e7 49 3b
RIP  [<ffffffff802af8e3>] proc_sys_readdir+0xd3/0x350
 RSP <ffff81007fd93e78>
CR2: ffffffff880661c0
Kernel panic - not syncing: Fatal exception
Signed-off-by: NAlexey Dobriyan <adobriyan@gmail.com>
Acked-by: NTrond Myklebust <trond.myklebust@fys.uio.no>
Cc: "J. Bruce Fields" <bfields@fieldses.org>
Cc: <stable@kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Convert asserts (BUGs) in dx_probe from bad on-disk data to recoverable
errors with helpful warnings.  With help catching other asserts from Duane
Griffin <duaneg@dghda.com>
Signed-off-by: NEric Sandeen <sandeen@redhat.com>
Acked-by: NDuane Griffin <duaneg@dghda.com>
Acked-by: NTheodore Ts'o <tytso@mit.edu>
Cc: <stable@kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

SGI-PV: 969656
SGI-Modid: xfs-linux-melb:xfs-kern:29676a
Signed-off-by: NLachlan McIlroy <lachlan@sgi.com>
Signed-off-by: NDavid Chinner <dgc@sgi.com>
Signed-off-by: NTim Shimmin <tes@sgi.com>

SGI-PV: 968767
SGI-Modid: xfs-linux-melb:xfs-kern:29675a
Signed-off-by: NLachlan McIlroy <lachlan@sgi.com>
Signed-off-by: NDavid Chinner <dgc@sgi.com>
Signed-off-by: NTim Shimmin <tes@sgi.com>

Instead of running the mru cache reaper all the time based on a timeout,
we should only run it when the cache has active objects. This allows CPUs
to sleep when there is no activity rather than be woken repeatedly just to
check if there is anything to do.

SGI-PV: 968554
SGI-Modid: xfs-linux-melb:xfs-kern:29305a
Signed-off-by: NDavid Chinner <dgc@sgi.com>
Signed-off-by: NDonald Douwsma <donaldd@sgi.com>
Signed-off-by: NTim Shimmin <tes@sgi.com>

on return from ioctl calls
Signed-off-by: NMasakazu Mokuno <mokuno@sm.sony.co.jp>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

The inode->i_flock list contains the leases, flocks and posix
locks in the specified order. However, the flocks are added in
the head of this list thus hiding the leases from F_GETLEASE
command, from time_out_leases() and other code that expects
the leases to come first.

The following example will demonstrate this:

#define _GNU_SOURCE

#include <unistd.h>
#include <fcntl.h>
#include <stdio.h>
#include <sys/file.h>

static void show_lease(int fd)
{
        int res;

        res = fcntl(fd, F_GETLEASE);
        switch (res) {
                case F_RDLCK:
                        printf("Read lease\n");
                        break;
                case F_WRLCK:
                        printf("Write lease\n");
                        break;
                case F_UNLCK:
                        printf("No leases\n");
                        break;
                default:
                        printf("Some shit\n");
                        break;
        }
}

int main(int argc, char **argv)
{
        int fd, res;

        fd = open(argv[1], O_RDONLY);
        if (fd == -1) {
                perror("Can't open file");
                return 1;
        }

        res = fcntl(fd, F_SETLEASE, F_WRLCK);
        if (res == -1) {
                perror("Can't set lease");
                return 1;
        }

        show_lease(fd);

        if (flock(fd, LOCK_SH) == -1) {
                perror("Can't flock shared");
                return 1;
        }

        show_lease(fd);

        return 0;
}

The first call to show_lease() will show the write lease set, but
the second will show no leases.

Fix the flock adding so that the leases always stay in the head
of this list.

Found during making the flocks pid-namespaces aware.
Signed-off-by: NPavel Emelyanov <xemul@openvz.org>
Acked-by: N"J. Bruce Fields" <bfields@fieldses.org>
Cc: Trond Myklebust <trond.myklebust@fys.uio.no>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: <stable@kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Taneli Vähäkangas <vahakang@cs.helsinki.fi> reported that commit
786d7e16 aka "Fix rmmod/read/write races
in /proc entries" broke SBCL + SLIME combo.

The old code in do_select() used DEFAULT_POLLMASK, if couldn't find
->poll handler.  The new code makes ->poll always there and returns 0 by
default, which is not correct.  Return DEFAULT_POLLMASK instead.

Steps to reproduce:

	install emacs, SBCL, SLIME
	emacs
	M-x slime	in *inferior-lisp* buffer
	[watch it doing "Connecting to Swank on port X.."]

Please, apply before 2.6.23.

P.S.: why SBCL can't just read(2) /proc/cpuinfo is a mystery.
Signed-off-by: NAlexey Dobriyan <adobriyan@gmail.com>
Cc: T Taneli Vahakangas <vahakang@cs.helsinki.fi>
Cc: Oleg Nesterov <oleg@tv-sign.ru>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

dput must be called before mntput here.
Signed-off-by: NAndreas Gruenbacher <agruen@suse.de>
Acked-By: NDavid Howells <dhowells@redhat.com>
Cc: <stable@kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

If we fail to start a transaction when releasing dquot, we have to call
dquot_release() anyway to mark dquot structure as inactive.  Otherwise we
end in an infinite loop inside dqput().
Signed-off-by: NJan Kara <jack@suse.cz>
Cc: xb <xavier.bru@bull.net>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

We were setting i_blocks too early - before truncating any allocation.
Correct things to set i_blocks after the allocation change.
Signed-off-by: NMark Fasheh <mark.fasheh@oracle.com>

In ocfs2_alloc_write_write_ctxt, the written clusters length is calculated
by the byte length only. This may cause some problems if we start to write
at some position in the end of one cluster and last to a second cluster
while the "len" is smaller than a cluster size. In that case, we have to
write 2 clusters actually.
So we have to take the start position into consideration also.
Signed-off-by: NTao Ma <tao.ma@oracle.com>
Signed-off-by: NMark Fasheh <mark.fasheh@oracle.com>

For some mount option types, ocfs2_parse_options() will try to access
sb->s_fs_info to get at the ocfs2 private superblock. Unfortunately, that
hasn't been allocated yet and will cause a kernel crash.

Fix this by storing options in a struct which can then get pushed into the
ocfs2_super once it's been allocated later. If we need more options which
store to the ocfs2_super in the future, we can just fields to this struct.
Signed-off-by: NTiger Yang <tiger.yang@oracle.com>
Signed-off-by: NMark Fasheh <mark.fasheh@oracle.com>

Update documentation listing ocfs2 features to reflect the current state of
the file system. Add missing descriptions for some mount options which ocfs2
supports.
Signed-off-by: NMark Fasheh <mark.fasheh@oracle.com>

fsid_source decided where to get the 'fsid' number to
return for a GETATTR based on the type of filehandle.
It can be from the device, from the fsid, or from the
UUID.

It is possible for the filehandle to be inconsistent
with the export information, so make sure the export information
actually has the info implied by the value returned by
fsid_source.
Signed-off-by: NNeil Brown <neilb@suse.de>
Cc: "Luiz Fernando N. Capitulino" <lcapitulino@gmail.com>
Signed-off-by: N"J. Bruce Fields" <bfields@citi.umich.edu>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>