This gives the filesystem more information about the writeback that
is happening.  Trond requested this for the NFS unstable write handling,
and other filesystems might benefit from this too by beeing able to
distinguish between the different callers in more detail.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Similar to the fsync issue fixed a while ago in commit
2daea67e we need to write for data to
actually hit the disk before writing out the metadata to guarantee
data integrity for filesystems that modify the inode in the data I/O
completion path.  Currently XFS and NFS handle this manually, and AFS
has a write_inode method that does nothing but waiting for data, while
others are possibly missing out on this.

Fortunately this change has a lot less impact than the fsync change
as none of the write_inode methods starts data writeout of any form
by itself.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

rehashing the negative placeholder opens a race with d_lookup();
we unhash it almost immediately (by d_move()), but the race
window is there.  Since d_move() doesn't rely on target being
hashed, we don't need that d_rehash() at all.
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

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

Add a new UMOUNT_NOFOLLOW flag to umount(2).  This is needed to prevent
symlink attacks in unprivileged unmounts (fuse, samba, ncpfs).

Additionally, return -EINVAL if an unknown flag is used (and specify
an explicitly unused flag: UMOUNT_UNUSED).  This makes it possible for
the caller to determine if a flag is supported or not.

CC: Eugene Teo <eugene@redhat.com>
CC: Michael Kerrisk <mtk.manpages@gmail.com>
Signed-off-by: NMiklos Szeredi <mszeredi@suse.cz>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

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

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

It hadn't been needed since we'd sanitized the logics in
mark_mounts_for_expiry() (which, in turn, used to be a
rudiment of bad old times when namespace_sem was per-ns).
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

no more users left outside of fs/*.c (and very few outside of
fs/namespace.c, actually)
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

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

Just use dentry_unhash() there
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

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

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

... especially when it only needs (and initializes) .d_name of it
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

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

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

apply function to vfsmounts in set returned by collect_mounts(),
stop if it returns non-zero.
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

RFC says we need to follow the chain of mounts if there's more
than one stacked on that point.
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

No need to open-code follow_up() in it and locking can be lighter.
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

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

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

Analog of is_subdir for vfsmount,dentry pairs, moved from audit_tree.c
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

The handling of mount flags in set_mnt_shared() got a little tangled
up during previous cleanups, with the following problems:

* MNT_PNODE_MASK is defined as a literal constant when it should be a
bitwise xor of other MNT_* flags
* set_mnt_shared() clears and then sets MNT_SHARED (part of MNT_PNODE_MASK)
* MNT_PNODE_MASK could use a comment in mount.h
* MNT_PNODE_MASK is a terrible name, change to MNT_SHARED_MASK

This patch fixes these problems.
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

... and get rid of open-coding its guts (i.e. RIP autofs4_force_release())
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

path to mnt/mnt->mnt_root is no worse than that to
mnt->mnt_parent/mnt->mnt_mountpoint *and* needs no
pinning the sucker down (mnt is not going away and
mnt->mnt_root won't change)
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

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

First of all, get_source() never results in CL_PROPAGATION
alone.  We either get CL_MAKE_SHARED (for the continuation
of peer group) or CL_SLAVE (slave that is not shared) or both
(beginning of peer group among slaves).  Massage the code to
make that explicit, kill CL_PROPAGATION test in clone_mnt()
(nothing sets CL_MAKE_SHARED without CL_PROPAGATION and in
clone_mnt() we are checking CL_PROPAGATION after we'd found
that there's no CL_SLAVE, so the check for CL_MAKE_SHARED
would do just as well).

Fix comments, while we are at it...
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

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

... instead of mixing FMODE_ and O_
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Invalidate sb->s_bdev on remount,ro.

Fixes a problem reported by Jorge Boncompte who is seeing corruption
trying to snapshot a minix filesystem image.  Some filesystems modify
their metadata via a path other than the bdev buffer cache (eg.  they may
use a private linear mapping for their metadata, or implement directories
in pagecache, etc).  Also, file data modifications usually go to the bdev
via their own mappings.

These updates are not coherent with buffercache IO (eg.  via /dev/bdev)
and never have been.  However there could be a reasonable expectation that
after a mount -oremount,ro operation then the buffercache should
subsequently be coherent with previous filesystem modifications.

So invalidate the bdev mappings on a remount,ro operation to provide a
coherency point.

The problem was exposed when we switched the old rd to brd because old rd
didn't really function like a normal block device and updates to rd via
mappings other than the buffercache would still end up going into its
buffercache.  But the same problem has always affected other "normal"
block devices, including loop.

[akpm@linux-foundation.org: repair comment layout]
Reported-by: N"Jorge Boncompte [DTI2]" <jorge@dti2.net>
Tested-by: N"Jorge Boncompte [DTI2]" <jorge@dti2.net>
Signed-off-by: NNick Piggin <npiggin@suse.de>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Cleanup EXPORT* macros according to Documantation/CodingStyle.

Move EXPORT* macros to the line immediately after the closing
function brace.
Signed-off-by: NH Hartley Sweeten <hsweeten@visionengravers.com>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

EXPORT_SYMBOL(proc_symlink);
EXPORT_SYMBOL(proc_mkdir);
EXPORT_SYMBOL(create_proc_entry);
EXPORT_SYMBOL(proc_create_data);
EXPORT_SYMBOL(remove_proc_entry);

Those EXPORT_SYMBOL shouldn't be in fs/proc/root.c,
should be in fs/proc/generic.c.
Signed-off-by: NHelight.Xu <helight.xu@gmail.com>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Remove the EXPORT_UNUSED_SYMBOL of simple_prepare_write

Collapse simple_prepare_write into it's only caller, though
making it simpler and clearer to understand.
Signed-off-by: NBoaz Harrosh <bharrosh@panasas.com>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

* simple_commit_write was only called by simple_write_end.
  Open coding it makes it tiny bit less heavy on the arithmetic and
  much more readable.

* While at it use zero_user() for clearing a partial page.
* While at it add a docbook comment for simple_write_end.
Signed-off-by: NBoaz Harrosh <bharrosh@panasas.com>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

This reverts commit 213614d5.

Alas, ->d_revalidate() can't rely on ->lookup() finishing what
it's started; if d_alloc() in do_lookup() fails, we are not going
to call ->lookup() at all.
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Currently we were adding ioctl cmds/structures for ocfs2 into ocfs2_fs.h
which was used for define ocfs2 on-disk layout. That sounds a little bit
confusing, and it may be quickly polluted espcially when growing the
ocfs2_info_request ioctls afterwards(it will grow i bet).

As a result, such OCFS2 IOCs do need to be placed somewhere other than
ocfs2_fs.h, a separated ocfs2_ioctl.h will be added to store such ioctl
structures and definitions which could also be used from userspace to
invoke ioctls call.
Signed-off-by: NTristan Ye <tristan.ye@oracle.com>
Signed-off-by: NJoel Becker <joel.becker@oracle.com>

This reverts commit 9f7cdbc3.

It's causing oopses om dm setups, so revert it until we investigate.
Reported-by: NDmitry Torokhov <dmitry.torokhov@gmail.com>
Tested-by: NSteven Rostedt <rostedt@goodmis.org>
Signed-off-by: NJens Axboe <jens.axboe@oracle.com>

This patch changes glock numbers from printing in decimal to hex.
Since DLM prints corresponding resource IDs in hex, it makes debugging
easier.
Signed-off-by: NBob Peterson <rpeterso@redhat.com>
Signed-off-by: NSteven Whitehouse <swhiteho@redhat.com>

When we queue data buffers for ordered write, the buffers are added
to the head of the ordered write list. When the log needs to push
these buffers to disk, it also walks the list from the head. The
result is that the the ordered buffers are submitted to disk in
reverse order.

For large writes, this means that whenever the log flushes large
streams of reverse sequential order buffers are pushed down into the
block layers. The elevators don't handle this particularly well, so
IO rates tend to be significantly lower than if the IO was issued in
ascending block order.

Queue new ordered buffers to the tail of the ordered buffer list to
ensure that IO is dispatched in the order it was submitted. This
should significantly improve large sequential write speeds. On a
disk capable of 85MB/s, speeds increase from 50MB/s to 65MB/s for
noop and from 38MB/s to 50MB/s for cfq.
Signed-off-by: NDave Chinner <dchinner@redhat.com>
Signed-off-by: NSteven Whitehouse <swhiteho@redhat.com>

As a consequence of the previous patch, we can now remove the
loop which used to be required due to the circular dependency
between the inodes and glocks. Instead we can just invalidate
the inodes, and then clear up any glocks which are left.

Also we no longer need the rwsem since there is no longer any
danger of the inode invalidation calling back into the glock
code (and from there back into the inode code).
Signed-off-by: NSteven Whitehouse <swhiteho@redhat.com>