Commit Graph

41981 Commits

Author SHA1 Message Date
Jeff Layton
5c1c669a1b locks: don't allocate a lock context for an F_UNLCK request
In the event that we get an F_UNLCK request on an inode that has no lock
context, there is no reason to allocate one. Change
locks_get_lock_context to take a "type" pointer and avoid allocating a
new context if it's F_UNLCK.

Then, fix the callers to return appropriately if that function returns
NULL.

Signed-off-by: Jeff Layton <jlayton@primarydata.com>
2015-04-03 09:04:03 -04:00
Daniel Wagner
663d5af750 locks: Add lockdep assertion for blocked_lock_lock
Annonate insert, remove and iterate function that we need
blocked_lock_lock held.

Signed-off-by: Daniel Wagner <daniel.wagner@bmw-carit.de>
Signed-off-by: Jeff Layton <jeff.layton@primarydata.com>
2015-04-03 09:04:03 -04:00
Jeff Layton
9b8c86956d locks: remove extraneous IS_POSIX and IS_FLOCK tests
We know that the locks being passed into this function are of the
correct type, now that they live on their own lists.

Signed-off-by: Jeff Layton <jeff.layton@primarydata.com>
2015-04-03 09:04:02 -04:00
Daniel Wagner
9cd29044bd locks: Remove unnecessary IS_POSIX test
Since following change

commit bd61e0a9c8
Author: Jeff Layton <jlayton@primarydata.com>
Date:   Fri Jan 16 15:05:55 2015 -0500

    locks: convert posix locks to file_lock_context

all Posix locks are kept on their a separate list, so the test is
redudant.

Signed-off-by: Daniel Wagner <daniel.wagner@bmw-carit.de>
Cc: Jeff Layton <jlayton@primarydata.com>
Cc: "J. Bruce Fields" <bfields@fieldses.org>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Jeff Layton <jeff.layton@primarydata.com>
2015-04-03 09:04:02 -04:00
Eric Whitney
9d21c9fa2c ext4: don't release reserved space for previously allocated cluster
When xfstests' auto group is run on a bigalloc filesystem with a
4.0-rc3 kernel, e2fsck failures and kernel warnings occur for some
tests. e2fsck reports incorrect iblocks values, and the warnings
indicate that the space reserved for delayed allocation is being
overdrawn at allocation time.

Some of these errors occur because the reserved space is incorrectly
decreased by one cluster when ext4_ext_map_blocks satisfies an
allocation request by mapping an unused portion of a previously
allocated cluster.  Because a cluster's worth of reserved space was
already released when it was first allocated, it should not be released
again.

This patch appears to correct the e2fsck failure reported for
generic/232 and the kernel warnings produced by ext4/001, generic/009,
and generic/033.  Failures and warnings for some other tests remain to
be addressed.

Signed-off-by: Eric Whitney <enwlinux@gmail.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2015-04-03 00:17:31 -04:00
Eric Whitney
94426f4b96 ext4: fix loss of delalloc extent info in ext4_zero_range()
In ext4_zero_range(), removing a file's entire block range from the
extent status tree removes all records of that file's delalloc extents.
The delalloc accounting code uses this information, and its loss can
then lead to accounting errors and kernel warnings at writeback time and
subsequent file system damage.  This is most noticeable on bigalloc
file systems where code in ext4_ext_map_blocks() handles cases where
delalloc extents share clusters with a newly allocated extent.

Because we're not deleting a block range and are correctly updating the
status of its associated extent, there is no need to remove anything
from the extent status tree.

When this patch is combined with an unrelated bug fix for
ext4_zero_range(), kernel warnings and e2fsck errors reported during
xfstests runs on bigalloc filesystems are greatly reduced without
introducing regressions on other xfstests-bld test scenarios.

Signed-off-by: Eric Whitney <enwlinux@gmail.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2015-04-03 00:13:42 -04:00
Lukas Czerner
0f2af21aae ext4: allocate entire range in zero range
Currently there is a bug in zero range code which causes zero range
calls to only allocate block aligned portion of the range, while
ignoring the rest in some cases.

In some cases, namely if the end of the range is past i_size, we do
attempt to preallocate the last nonaligned block. However this might
cause kernel to BUG() in some carefully designed zero range requests
on setups where page size > block size.

Fix this problem by first preallocating the entire range, including
the nonaligned edges and converting the written extents to unwritten
in the next step. This approach will also give us the advantage of
having the range to be as linearly contiguous as possible.

Signed-off-by: Lukas Czerner <lczerner@redhat.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2015-04-03 00:09:13 -04:00
Maurizio Lombardi
5a4f3145aa ext4: remove unnecessary lock/unlock of i_block_reservation_lock
This is a leftover of commit 71d4f7d032

Signed-off-by: Maurizio Lombardi <mlombard@redhat.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Lukas Czerner <lczerner@redhat.com>
2015-04-03 00:02:53 -04:00
Christoph Hellwig
08439fec26 ext4: remove block_device_ejected
bdi->dev now never goes away, so this function became useless.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2015-04-02 23:56:32 -04:00
Wei Yuan
5f80f62ada ext4: remove useless condition in if statement.
In this if statement, the previous condition is useless, the later one
has covered it.

Signed-off-by: Weiyuan <weiyuan.wei@huawei.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Lukas Czerner <lczerner@redhat.com>
2015-04-02 23:50:48 -04:00
Sheng Yong
72b8e0f9fa ext4: remove unused header files
Remove unused header files and header files which are included in
ext4.h.

Signed-off-by: Sheng Yong <shengyong1@huawei.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2015-04-02 23:47:42 -04:00
Eric W. Biederman
0c56fe3142 mnt: Don't propagate unmounts to locked mounts
If the first mount in shared subtree is locked don't unmount the
shared subtree.

This is ensured by walking through the mounts parents before children
and marking a mount as unmountable if it is not locked or it is locked
but it's parent is marked.

This allows recursive mount detach to propagate through a set of
mounts when unmounting them would not reveal what is under any locked
mount.

Cc: stable@vger.kernel.org
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2015-04-02 20:34:20 -05:00
Eric W. Biederman
5d88457eb5 mnt: On an unmount propagate clearing of MNT_LOCKED
A prerequisite of calling umount_tree is that the point where the tree
is mounted at is valid to unmount.

If we are propagating the effect of the unmount clear MNT_LOCKED in
every instance where the same filesystem is mounted on the same
mountpoint in the mount tree, as we know (by virtue of the fact
that umount_tree was called) that it is safe to reveal what
is at that mountpoint.

Cc: stable@vger.kernel.org
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2015-04-02 20:34:19 -05:00
Eric W. Biederman
411a938b5a mnt: Delay removal from the mount hash.
- Modify __lookup_mnt_hash_last to ignore mounts that have MNT_UMOUNTED set.
- Don't remove mounts from the mount hash table in propogate_umount
- Don't remove mounts from the mount hash table in umount_tree before
  the entire list of mounts to be umounted is selected.
- Remove mounts from the mount hash table as the last thing that
  happens in the case where a mount has a parent in umount_tree.
  Mounts without parents are not hashed (by definition).

This paves the way for delaying removal from the mount hash table even
farther and fixing the MNT_LOCKED vs MNT_DETACH issue.

Cc: stable@vger.kernel.org
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2015-04-02 20:34:19 -05:00
Eric W. Biederman
590ce4bcbf mnt: Add MNT_UMOUNT flag
In some instances it is necessary to know if the the unmounting
process has begun on a mount.  Add MNT_UMOUNT to make that reliably
testable.

This fix gets used in fixing locked mounts in MNT_DETACH

Cc: stable@vger.kernel.org
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2015-04-02 20:34:18 -05:00
Eric W. Biederman
c003b26ff9 mnt: In umount_tree reuse mnt_list instead of mnt_hash
umount_tree builds a list of mounts that need to be unmounted.
Utilize mnt_list for this purpose instead of mnt_hash.  This begins to
allow keeping a mount on the mnt_hash after it is unmounted, which is
necessary for a properly functioning MNT_LOCKED implementation.

The fact that mnt_list is an ordinary list makding available list_move
is nice bonus.

Cc: stable@vger.kernel.org
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2015-04-02 20:34:18 -05:00
Eric W. Biederman
8318e667f1 mnt: Don't propagate umounts in __detach_mounts
Invoking mount propagation from __detach_mounts is inefficient and
wrong.

It is inefficient because __detach_mounts already walks the list of
mounts that where something needs to be done, and mount propagation
walks some subset of those mounts again.

It is actively wrong because if the dentry that is passed to
__detach_mounts is not part of the path to a mount that mount should
not be affected.

change_mnt_propagation(p,MS_PRIVATE) modifies the mount propagation
tree of a master mount so it's slaves are connected to another master
if possible.  Which means even removing a mount from the middle of a
mount tree with __detach_mounts will not deprive any mount propagated
mount events.

Cc: stable@vger.kernel.org
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2015-04-02 20:34:17 -05:00
Eric W. Biederman
e819f15210 mnt: Improve the umount_tree flags
- Remove the unneeded declaration from pnode.h
- Mark umount_tree static as it has no callers outside of namespace.c
- Define an enumeration of umount_tree's flags.
- Pass umount_tree's flags in by name

This removes the magic numbers 0, 1 and 2 making the code a little
clearer and makes it possible for there to be lazy unmounts that don't
propagate.  Which is what __detach_mounts actually wants for example.

Cc: stable@vger.kernel.org
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2015-04-02 20:34:17 -05:00
Eric W. Biederman
a3b3c5627c mnt: Use hlist_move_list in namespace_unlock
Small cleanup to make the code more readable and maintainable.

Signed-off-by: Eric Biederman <ebiederm@xmission.com>
2015-04-02 20:33:53 -05:00
Xiaoguang Wang
4255c224b9 ext4: fix comments in ext4_can_extents_be_merged()
Since commit a9b8241594, we are allowed to merge unwritten extents,
so here these comments are wrong, remove it.

Signed-off-by: Xiaoguang Wang <wangxg.fnst@cn.fujitsu.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2015-04-02 16:53:11 -04:00
Rasmus Villemoes
80cfb71e2e ext4: fix transposition typo in format string
According to C99, %*.s means the same as %*.0s, in other words, print as
many spaces as the field width argument says and effectively ignore the
string argument. That is certainly not what was meant here. The kernel's
printf implementation, however, treats it as if the . was not there,
i.e. as %*s. I don't know if de->name is nul-terminated or not, but in
any case I'm guessing the intention was to use de->name_len as precision
instead of field width.

[ Note: this is debugging code which is commented out, so this is not
  security issue; a developer would have to explicitly enable
  INLINE_DIR_DEBUG before this would be an issue. ]

Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2015-04-02 16:42:43 -04:00
Konstantin Khlebnikov
7071b71587 ext4: fix bh leak on error paths in ext4_rename() and ext4_cross_rename()
Release references to buffer-heads if ext4_journal_start() fails.

Fixes: 5b61de7575 ("ext4: start handle at least possible moment when renaming files")
Signed-off-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Jan Kara <jack@suse.cz>
2015-04-02 16:32:15 -04:00
David Howells
4a47132ff4 FS-Cache: Retain the netfs context in the retrieval op earlier
Now that the retrieval operation may be disposed of by fscache_put_operation()
before we actually set the context, the retrieval-specific cleanup operation
can produce a NULL-pointer dereference when it tries to unconditionally clean
up the netfs context.

Given that it is expected that we'll get at least as far as the place where we
currently set the context pointer and it is unlikely we'll go through the
error handling paths prior to that point, retain the context right from the
point that the retrieval op is allocated.

Concomitant to this, we need to retain the cookie pointer in the retrieval op
also so that we can call the netfs to release its context in the release
method.

In addition, we might now get into fscache_release_retrieval_op() with the op
only initialised.  To this end, set the operation to DEAD only after the
release method has been called and skip the n_pages test upon cleanup if the
op is still in the INITIALISED state.

Without these changes, the following oops might be seen:

	BUG: unable to handle kernel NULL pointer dereference at 00000000000000b8
	...
	RIP: 0010:[<ffffffffa0089c98>] fscache_release_retrieval_op+0xae/0x100
	...
	Call Trace:
	 [<ffffffffa0088560>] fscache_put_operation+0x117/0x2e0
	 [<ffffffffa008b8f5>] __fscache_read_or_alloc_pages+0x351/0x3ac
	 [<ffffffffa00b761f>] __nfs_readpages_from_fscache+0x59/0xbf [nfs]
	 [<ffffffffa00b06c5>] nfs_readpages+0x10c/0x185 [nfs]
	 [<ffffffff81124925>] ? alloc_pages_current+0x119/0x13e
	 [<ffffffff810ee5fd>] ? __page_cache_alloc+0xfb/0x10a
	 [<ffffffff810f87f8>] __do_page_cache_readahead+0x188/0x22c
	 [<ffffffff810f8b3a>] ondemand_readahead+0x29e/0x2af
	 [<ffffffff810f8c92>] page_cache_sync_readahead+0x38/0x3a
	 [<ffffffff810ef337>] generic_file_read_iter+0x1a2/0x55a
	 [<ffffffffa00a9dff>] ? nfs_revalidate_mapping+0xd6/0x288 [nfs]
	 [<ffffffffa00a6a23>] nfs_file_read+0x49/0x70 [nfs]
	 [<ffffffff811363be>] new_sync_read+0x78/0x9c
	 [<ffffffff81137164>] __vfs_read+0x13/0x38
	 [<ffffffff8113721e>] vfs_read+0x95/0x121
	 [<ffffffff811372f6>] SyS_read+0x4c/0x8a
	 [<ffffffff81557a52>] system_call_fastpath+0x12/0x17

Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Steve Dickson <steved@redhat.com>
Acked-by: Jeff Layton <jeff.layton@primarydata.com>
2015-04-02 14:28:53 +01:00
David Howells
d3b97ca4a9 FS-Cache: The operation cancellation method needs calling in more places
Any time an incomplete operation is cancelled, the operation cancellation
function needs to be called to clean up.  This is currently being passed
directly to some of the functions that might want to call it, but not all.

Instead, pass the cancellation method pointer to the fscache_operation_init()
and have that cache it in the operation struct.  Further, plug in a dummy
cancellation handler if the caller declines to set one as this allows us to
call the function unconditionally (the extra overhead isn't worth bothering
about as we don't expect to be calling this typically).

The cancellation method must thence be called everywhere the CANCELLED state
is set.  Note that we call it *before* setting the CANCELLED state such that
the method can use the old state value to guide its operation.

fscache_do_cancel_retrieval() needs moving higher up in the sources so that
the init function can use it now.

Without this, the following oops may be seen:

	FS-Cache: Assertion failed
	FS-Cache: 3 == 0 is false
	------------[ cut here ]------------
	kernel BUG at ../fs/fscache/page.c:261!
	...
	RIP: 0010:[<ffffffffa0089c1b>]  fscache_release_retrieval_op+0x77/0x100
	 [<ffffffffa008853d>] fscache_put_operation+0x114/0x2da
	 [<ffffffffa008b8c2>] __fscache_read_or_alloc_pages+0x358/0x3b3
	 [<ffffffffa00b761f>] __nfs_readpages_from_fscache+0x59/0xbf [nfs]
	 [<ffffffffa00b06c5>] nfs_readpages+0x10c/0x185 [nfs]
	 [<ffffffff81124925>] ? alloc_pages_current+0x119/0x13e
	 [<ffffffff810ee5fd>] ? __page_cache_alloc+0xfb/0x10a
	 [<ffffffff810f87f8>] __do_page_cache_readahead+0x188/0x22c
	 [<ffffffff810f8b3a>] ondemand_readahead+0x29e/0x2af
	 [<ffffffff810f8c92>] page_cache_sync_readahead+0x38/0x3a
	 [<ffffffff810ef337>] generic_file_read_iter+0x1a2/0x55a
	 [<ffffffffa00a9dff>] ? nfs_revalidate_mapping+0xd6/0x288 [nfs]
	 [<ffffffffa00a6a23>] nfs_file_read+0x49/0x70 [nfs]
	 [<ffffffff811363be>] new_sync_read+0x78/0x9c
	 [<ffffffff81137164>] __vfs_read+0x13/0x38
	 [<ffffffff8113721e>] vfs_read+0x95/0x121
	 [<ffffffff811372f6>] SyS_read+0x4c/0x8a
	 [<ffffffff81557a52>] system_call_fastpath+0x12/0x17

The assertion is showing that the remaining number of pages (n_pages) is not 0
when the operation is being released.

Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Steve Dickson <steved@redhat.com>
Acked-by: Jeff Layton <jeff.layton@primarydata.com>
2015-04-02 14:28:53 +01:00
David Howells
a39caadf06 FS-Cache: Put an aborted initialised op so that it is accounted correctly
Call fscache_put_operation() or a wrapper on any op that has gone through
fscache_operation_init() so that the accounting shown in /proc is done
correctly, specifically fscache_n_op_release.

fscache_put_operation() therefore now allows an op in the INITIALISED state as
well as in the CANCELLED and COMPLETE states.

Note that this means that an operation can get put that doesn't have its
->object pointer filled in, so anything that depends on the object needs to be
conditional in fscache_put_operation().

Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Steve Dickson <steved@redhat.com>
Acked-by: Jeff Layton <jeff.layton@primarydata.com>
2015-04-02 14:28:53 +01:00
David Howells
73c04a47bf FS-Cache: Fix cancellation of in-progress operation
Cancellation of an in-progress operation needs to update the relevant counters
and start any operations that are pending waiting on this one.

Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Steve Dickson <steved@redhat.com>
Acked-by: Jeff Layton <jeff.layton@primarydata.com>
2015-04-02 14:28:53 +01:00
David Howells
03cdd0e4b9 FS-Cache: Count the number of initialised operations
Count and display through /proc/fs/fscache/stats the number of initialised
operations.

Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Steve Dickson <steved@redhat.com>
Acked-by: Jeff Layton <jeff.layton@primarydata.com>
2015-04-02 14:28:53 +01:00
David Howells
1339ec98e3 FS-Cache: Out of line fscache_operation_init()
Out of line fscache_operation_init() so that it can access internal FS-Cache
features, such as stats, in a later commit.

Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Steve Dickson <steved@redhat.com>
Acked-by: Jeff Layton <jeff.layton@primarydata.com>
2015-04-02 14:28:53 +01:00
David Howells
418b7eb9e1 FS-Cache: Permit fscache_cancel_op() to cancel in-progress operations too
Currently, fscache_cancel_op() only cancels pending operations - attempts to
cancel in-progress operations are ignored.  This leads to a problem in
fscache_wait_for_operation_activation() whereby the wait is terminated, but
the object has been killed.

The check at the end of the function now triggers because it's no longer
contingent on the cache having produced an I/O error since the commit that
fixed the logic error in fscache_object_is_dead().

The result of the check is that it tries to cancel the operation - but since
the object may not be pending by this point, the cancellation request may be
ignored - with the result that the the object is just put by the caller and
fscache_put_operation has an assertion failure because the operation isn't in
either the COMPLETE or the CANCELLED states.

To fix this, we permit in-progress ops to be cancelled under some
circumstances.

The bug results in an oops that looks something like this:

	FS-Cache: fscache_wait_for_operation_activation() = -ENOBUFS [obj dead 3]
	FS-Cache:
	FS-Cache: Assertion failed
	FS-Cache: 3 == 5 is false
	------------[ cut here ]------------
	kernel BUG at ../fs/fscache/operation.c:432!
	...
	RIP: 0010:[<ffffffffa0088574>] fscache_put_operation+0xf2/0x2cd
	Call Trace:
	 [<ffffffffa008b92a>] __fscache_read_or_alloc_pages+0x2ec/0x3b3
	 [<ffffffffa00b761f>] __nfs_readpages_from_fscache+0x59/0xbf [nfs]
	 [<ffffffffa00b06c5>] nfs_readpages+0x10c/0x185 [nfs]
	 [<ffffffff81124925>] ? alloc_pages_current+0x119/0x13e
	 [<ffffffff810ee5fd>] ? __page_cache_alloc+0xfb/0x10a
	 [<ffffffff810f87f8>] __do_page_cache_readahead+0x188/0x22c
	 [<ffffffff810f8b3a>] ondemand_readahead+0x29e/0x2af
	 [<ffffffff810f8c92>] page_cache_sync_readahead+0x38/0x3a
	 [<ffffffff810ef337>] generic_file_read_iter+0x1a2/0x55a
	 [<ffffffffa00a9dff>] ? nfs_revalidate_mapping+0xd6/0x288 [nfs]
	 [<ffffffffa00a6a23>] nfs_file_read+0x49/0x70 [nfs]
	 [<ffffffff811363be>] new_sync_read+0x78/0x9c
	 [<ffffffff81137164>] __vfs_read+0x13/0x38
	 [<ffffffff8113721e>] vfs_read+0x95/0x121
	 [<ffffffff811372f6>] SyS_read+0x4c/0x8a
	 [<ffffffff81557a52>] system_call_fastpath+0x12/0x17

Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Steve Dickson <steved@redhat.com>
Acked-by: Jeff Layton <jeff.layton@primarydata.com>
2015-04-02 14:28:53 +01:00
David Howells
8702152630 FS-Cache: fscache_object_is_dead() has wrong logic, kill it
fscache_object_is_dead() returns true only if the object is marked dead and
the cache got an I/O error.  This should be a logical OR instead.  Since two
of the callers got split up into handling for separate subcases, expand the
other callers and kill the function.  This is probably the right thing to do
anyway since one of the subcases isn't about the object at all, but rather
about the cache.

Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Steve Dickson <steved@redhat.com>
Acked-by: Jeff Layton <jeff.layton@primarydata.com>
2015-04-02 14:28:53 +01:00
David Howells
f09b443d0e FS-Cache: Synchronise object death state change vs operation submission
When an object is being marked as no longer live, do this under the object
spinlock to prevent a race with operation submission targeted on that object.

The problem occurs due to the following pair of intertwined sequences when the
cache tries to create an object that would take it over the hard available
space limit:

 NETFS INTERFACE
 ===============
 (A) The netfs calls fscache_acquire_cookie().  object creation is deferred to
     the object state machine and the netfs is allowed to continue.

	OBJECT STATE MACHINE KTHREAD
	============================
	(1) The object is looked up on disk by fscache_look_up_object()
	    calling cachefiles_walk_to_object().  The latter finds that the
	    object is not yet represented on disk and calls
	    fscache_object_lookup_negative().

	(2) fscache_object_lookup_negative() sets FSCACHE_COOKIE_NO_DATA_YET
	    and clears FSCACHE_COOKIE_LOOKING_UP, thus allowing the netfs to
	    start queuing read operations.

 (B) The netfs calls fscache_read_or_alloc_pages().  This calls
     fscache_wait_for_deferred_lookup() which sees FSCACHE_COOKIE_LOOKING_UP
     become clear, allowing the read to begin.

 (C) A read operation is set up and passed to fscache_submit_op() to deal
     with.

	(3) cachefiles_walk_to_object() calls cachefiles_has_space(), which
	    fails (or one of the file operations to create stuff fails).
	    cachefiles returns an error to fscache.

	(4) fscache_look_up_object() transits to the LOOKUP_FAILURE state,

	(5) fscache_lookup_failure() sets FSCACHE_OBJECT_LOOKED_UP and
	    FSCACHE_COOKIE_UNAVAILABLE and clears FSCACHE_COOKIE_LOOKING_UP
	    then transits to the KILL_OBJECT state.

	(6) fscache_kill_object() clears FSCACHE_OBJECT_IS_LIVE in an attempt
	    to reject any further requests from the netfs.

	(7) object->n_ops is examined and found to be 0.
	    fscache_kill_object() transits to the DROP_OBJECT state.

 (D) fscache_submit_op() locks the object spinlock, sees if it can dispatch
     the op immediately by calling fscache_object_is_active() - which fails
     since FSCACHE_OBJECT_IS_AVAILABLE has not yet been set.

 (E) fscache_submit_op() then tests FSCACHE_OBJECT_LOOKED_UP - which is set.
     It then queues the object and increments object->n_ops.

	(8) fscache_drop_object() releases the object and eventually
	    fscache_put_object() calls cachefiles_put_object() which suffers
	    an assertion failure here:

		ASSERTCMP(object->fscache.n_ops, ==, 0);

Locking the object spinlock in step (6) around the clearance of
FSCACHE_OBJECT_IS_LIVE ensures that the the decision trees in
fscache_submit_op() and fscache_submit_exclusive_op() don't see the IS_LIVE
flag being cleared mid-decision: either the op is queued before step (7) - in
which case fscache_kill_object() will see n_ops>0 and will deal with the op -
or the op will be rejected.

This, combined with rejecting op submission if the target object is dying, fix
the problem.

The problem shows up as the following oops:

CacheFiles: Assertion failed
CacheFiles: 1 == 0 is false
------------[ cut here ]------------
kernel BUG at ../fs/cachefiles/interface.c:339!
...
RIP: 0010:[<ffffffffa014fd9c>]  [<ffffffffa014fd9c>] cachefiles_put_object+0x2a4/0x301 [cachefiles]
...
Call Trace:
 [<ffffffffa008674b>] fscache_put_object+0x18/0x21 [fscache]
 [<ffffffffa00883e6>] fscache_object_work_func+0x3ba/0x3c9 [fscache]
 [<ffffffff81054dad>] process_one_work+0x226/0x441
 [<ffffffff81055d91>] worker_thread+0x273/0x36b
 [<ffffffff81055b1e>] ? rescuer_thread+0x2e1/0x2e1
 [<ffffffff81059b9d>] kthread+0x10e/0x116
 [<ffffffff81059a8f>] ? kthread_create_on_node+0x1bb/0x1bb
 [<ffffffff815579ac>] ret_from_fork+0x7c/0xb0
 [<ffffffff81059a8f>] ? kthread_create_on_node+0x1bb/0x1bb

Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Steve Dickson <steved@redhat.com>
Acked-by: Jeff Layton <jeff.layton@primarydata.com>
2015-04-02 14:28:53 +01:00
David Howells
6515d1dbf4 FS-Cache: Handle a new operation submitted against a killed object
Reject new operations that are being submitted against an object if that
object has failed its lookup or creation states or has been killed by the
cache backend for some other reason, such as having been culled.

Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Steve Dickson <steved@redhat.com>
Acked-by: Jeff Layton <jeff.layton@primarydata.com>
2015-04-02 14:28:53 +01:00
David Howells
30ceec6284 FS-Cache: When submitting an op, cancel it if the target object is dying
When submitting an operation, prefer to cancel the operation immediately
rather than queuing it for later processing if the object is marked as dying
(ie. the object state machine has reached the KILL_OBJECT state).

Whilst we're at it, change the series of related test_bit() calls into a
READ_ONCE() and bitwise-AND operators to reduce the number of load
instructions (test_bit() has a volatile address).

Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Steve Dickson <steved@redhat.com>
Acked-by: Jeff Layton <jeff.layton@primarydata.com>
2015-04-02 14:28:53 +01:00
David Howells
3c3059841a FS-Cache: Move fscache_report_unexpected_submission() to make it more available
Move fscache_report_unexpected_submission() up within operation.c so that it
can be called from fscache_submit_exclusive_op() too.

Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Steve Dickson <steved@redhat.com>
Acked-by: Jeff Layton <jeff.layton@primarydata.com>
2015-04-02 14:28:53 +01:00
Nathaniel Wesley Filardo
53d5864bc6 kafs: Add more "unified AFS" error codes
This should cover the set emitted by viced and the volume server.

Signed-off-by: Nathaniel Wesley Filardo <nwf@cs.jhu.edu>
Signed-off-by: David Howells <dhowells@redhat.com>
2015-04-01 21:36:15 +01:00
Guenter Roeck
4a3d1caf8a fs: btrfs: Add missing include file
Building alpha:allmodconfig fails with

fs/btrfs/inode.c: In function 'check_direct_IO':
fs/btrfs/inode.c:8050:2: error: implicit declaration of function 'iov_iter_alignment'

due to a missing include file.

Fixes: 3737c63e1fb0 ("fs: move struct kiocb to fs.h")
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Acked-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
2015-04-01 12:32:07 -07:00
Linus Torvalds
b6c3a5946c Merge tag 'lazytime_fix' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4
Pull lazytime fixes from Ted Ts'o:
 "This fixes a problem in the lazy time patches, which can cause
  frequently updated inods to never have their timestamps updated.

  These changes guarantee that no timestamp on disk will be stale by
  more than 24 hours"

* tag 'lazytime_fix' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4:
  fs: add dirtytime_expire_seconds sysctl
  fs: make sure the timestamps for lazytime inodes eventually get written
2015-04-01 10:05:42 -07:00
Linus Torvalds
1e848913f0 Merge branch 'for-4.0' of git://linux-nfs.org/~bfields/linux
Pull nfsd fixes from Bruce Fields:
 "Two main issues:

   - We found that turning on pNFS by default (when it's configured at
     build time) was too aggressive, so we want to switch the default
     before the 4.0 release.

   - Recent client changes to increase open parallelism uncovered a
     serious bug lurking in the server's open code.

  Also fix a krb5/selinux regression.

  The rest is mainly smaller pNFS fixes"

* 'for-4.0' of git://linux-nfs.org/~bfields/linux:
  sunrpc: make debugfs file creation failure non-fatal
  nfsd: require an explicit option to enable pNFS
  NFSD: Fix bad update of layout in nfsd4_return_file_layout
  NFSD: Take care the return value from nfsd4_encode_stateid
  NFSD: Printk blocklayout length and offset as format 0x%llx
  nfsd: return correct lockowner when there is a race on hash insert
  nfsd: return correct openowner when there is a race to put one in the hash
  NFSD: Put exports after nfsd4_layout_verify fail
  NFSD: Error out when register_shrinker() fail
  NFSD: Take care the return value from nfsd4_decode_stateid
  NFSD: Check layout type when returning client layouts
  NFSD: restore trace event lost in mismerge
2015-04-01 09:45:47 -07:00
Chris Mason
dd82525956 Btrfs: free and unlock our path before btrfs_free_and_pin_reserved_extent()
The error handling path for alloc_reserved_tree_block is calling
btrfs_free_and_pin_reserved_extent with a spinning tree lock held.  This
might sleep as we allocate extent_state objects:

 BUG: sleeping function called from invalid context at mm/slub.c:1268
 in_atomic(): 1, irqs_disabled(): 0, pid: 11093, name: kworker/u4:7
 5 locks held by kworker/u4:7/11093:
  #0:  ("%s-%s""btrfs", name){++++.+}, at: [<ffffffff81091d51>] process_one_work+0x151/0x520
  #1:  ((&work->normal_work)){+.+.+.}, at: [<ffffffff81091d51>] process_one_work+0x151/0x520
  #2:  (sb_internal){++++.+}, at: [<ffffffffa003a70e>] start_transaction+0x43e/0x590 [btrfs]
  #3:  (&head_ref->mutex){+.+...}, at: [<ffffffffa0089f8c>] btrfs_delayed_ref_lock+0x4c/0x240 [btrfs]
  #4:  (btrfs-extent-00){++++..}, at: [<ffffffffa007697b>] btrfs_clear_lock_blocking_rw+0x9b/0x150 [btrfs]
 CPU: 0 PID: 11093 Comm: kworker/u4:7 Tainted: G        W 4.0.0-rc6-default+ #246
 Hardware name: Intel Corporation Santa Rosa platform/Matanzas, BIOS TSRSCRB1.86C.0047.B00.0610170821 10/17/06
 Workqueue: btrfs-extent-refs btrfs_extent_refs_helper [btrfs]
  00000000000004f4 ffff88006dd17848 ffffffff81ab0e3b ffff88006dd17848
  ffff88007a944760 ffff88006dd17868 ffffffff8109d516 ffff88006dd17898
  0000000000000000 ffff88006dd17898 ffffffff8109d5b2 ffffffff81aba2bb
 Call Trace:
  [<ffffffff81ab0e3b>] dump_stack+0x4f/0x6c
  [<ffffffff8109d516>] ___might_sleep+0xf6/0x140
  [<ffffffff8109d5b2>] __might_sleep+0x52/0x90
  [<ffffffff81aba2bb>] ? ftrace_call+0x5/0x34
  [<ffffffff81196363>] kmem_cache_alloc+0x163/0x1b0
  [<ffffffffa0056f31>] ? alloc_extent_state+0x31/0x150 [btrfs]
  [<ffffffffa0056f20>] ? alloc_extent_state+0x20/0x150 [btrfs]
  [<ffffffffa0056f31>] alloc_extent_state+0x31/0x150 [btrfs]
  [<ffffffffa005805b>] __set_extent_bit+0x37b/0x5d0 [btrfs]
  [<ffffffff81aba2bb>] ? ftrace_call+0x5/0x34
  [<ffffffffa005888d>] ? set_extent_bit+0xd/0x30 [btrfs]
  [<ffffffffa00588a3>] set_extent_bit+0x23/0x30 [btrfs]
  [<ffffffffa0058e80>] set_extent_dirty+0x20/0x30 [btrfs]
  [<ffffffffa00195ba>] pin_down_extent+0xaa/0x170 [btrfs]
  [<ffffffffa001d8ef>] __btrfs_free_reserved_extent+0xcf/0x160 [btrfs]
  [<ffffffffa0023856>] btrfs_free_and_pin_reserved_extent+0x16/0x20 [btrfs]
  [<ffffffffa002482a>] __btrfs_run_delayed_refs+0xfca/0x1290 [btrfs]
  [<ffffffffa0026eae>] btrfs_run_delayed_refs+0x6e/0x2e0 [btrfs]
  [<ffffffffa0027378>] delayed_ref_async_start+0x48/0xb0 [btrfs]
  [<ffffffffa006c883>] normal_work_helper+0x83/0x350 [btrfs]
  [<ffffffffa006cd79>] ? btrfs_extent_refs_helper+0x9/0x20 [btrfs]
  [<ffffffffa006cd82>] btrfs_extent_refs_helper+0x12/0x20 [btrfs]
  [<ffffffff81091dcb>] process_one_work+0x1cb/0x520
  [<ffffffff81091d51>] ? process_one_work+0x151/0x520
  [<ffffffff811c7abf>] ? seq_read+0x3f/0x400
  [<ffffffff8109260b>] worker_thread+0x5b/0x4e0
  [<ffffffff81097be2>] ? __kthread_parkme+0x12/0xa0
  [<ffffffff810925b0>] ? rescuer_thread+0x450/0x450
  [<ffffffff81098686>] kthread+0xf6/0x120
  [<ffffffff81098590>] ? flush_kthread_worker+0x1b0/0x1b0
  [<ffffffff81ab8088>] ret_from_fork+0x58/0x90
  [<ffffffff81098590>] ? flush_kthread_worker+0x1b0/0x1b0
 ------------[ cut here ]------------

This changes things to free the path first, which will also unlock the
extent buffer.

Signed-off-by: Chris Mason <clm@fb.com>
Reported-by: Dave Sterba <dsterba@suse.cz>
Tested-by: Dave Sterba <dsterba@suse.cz>
2015-04-01 08:36:05 -07:00
David Howells
bfd4e9562c AFS: afs_send_empty_reply() doesn't require an iovec array
afs_send_empty_reply() doesn't require an iovec array with which to initialise
the msghdr, but can pass NULL instead.

Suggested-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David Howells <dhowells@redhat.com>
2015-04-01 16:03:46 +01:00
Jan Kara
3adc12e964 udf: Update ctime and mtime when directory is modified
We failed to update ctime & mtime of a directory when new entry was
created in it during rename, link, create, etc. Fix that.

Reported-by: Taesoo Kim <tsgatesv@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>
2015-04-01 14:26:14 +02:00
Changwoo Min
0fd2ba36b8 udf: return correct errno for udf_update_inode()
Instead of -ENOMEM, properly return -EIO udf_update_inode()
error, similar/consistent to the rest of filesystems.

Signed-off-by: Changwoo Min <changwoo.m@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>
2015-04-01 12:46:46 +02:00
Wei Yuan
78c3eb3c84 ext3: Remove useless condition in if statement.
In this if statement, the previous condition is useless, the later one has covered it.

Signed-off-by: Weiyuan <weiyuan.wei@huawei.com>
Reviewed-by: Lukas Czerner <lczerner@redhat.com>
Signed-off-by: Jan Kara <jack@suse.cz>
2015-04-01 09:39:49 +02:00
Steve French
4c5930e805 Fix warning
Coverity reports a warning due to unitialized attr structure in one
code path.

Reported by Coverity (CID 728535)

Signed-off-by: Steve French <smfrench@gmail.com>
Reviewed-by: Jeff Layton <jlayton@samba.org>
2015-04-01 00:01:47 -05:00
Steve French
dfebe40076 Fix another dereference before null check warning
null tcon is not possible in these paths so
remove confusing null check

Reported by Coverity (CID 728519)

Signed-off-by: Steve French <smfrench@gmail.com>
Reviewed-by: Jeff Layton <jlayton@samba.org>
2015-04-01 00:01:47 -05:00
Steve French
8b7a454443 CIFS: session servername can't be null
remove impossible check

Pointed out by Coverity (CID 115422)

Signed-off-by: Steve French <smfrench@gmail.com>
Reviewed-by: Jeff Layton <jlayton@samba.org>
2015-04-01 00:01:47 -05:00
Steve French
c85c35f8fc Fix warning on impossible comparison
workstation_RFC1001_name is part of the struct and can't be null,
remove impossible comparison (array vs. null)

Pointed out by Coverity (CID 140095)

Signed-off-by: Steve French <smfrench@gmail.com>
Reviewed-by: Jeff Layton <jlayton@samba.org>
2015-04-01 00:01:47 -05:00
Steve French
064bcc0702 Fix coverity warning
Coverity reports a warning for referencing the beginning of the
SMB2/SMB3 frame using the ProtocolId field as an array. Although
it works the same either way, this patch should quiet the warning
and might be a little clearer.

Reported by Coverity (CID 741269)

Signed-off-by: Steve French <smfrench@gmail.com>
Acked-by: Shirish Pargaonkar <shirishpargaonkar@gmail.com>
Acked-by: Sachin Prabhu <sprabhu@redhat.com>
Reviewed-by: Jeff Layton <jlayton@poochiereds.net>
2015-04-01 00:01:47 -05:00
Steve French
8e35310605 Fix dereference before null check warning
null tcon is not likely in these paths in current
code, but obviously it does clarify the code to
check for null (if at all) before derefrencing
rather than after.

Reported by Coverity (CID 1042666)

Signed-off-by: Steve French <smfrench@gmail.com>
Acked-by: Shirish Pargaonkar <shirishpargaonkar@gmail.com>
Acked-by: Sachin Prabhu <sprabhu@redhat.com>
2015-04-01 00:01:47 -05:00
Steve French
f3a31a2bbb Don't ignore errors on encrypting password in SMBTcon
Although unlikely to fail (and tree connect does not commonly send
a password since SECMODE_USER is the default for most servers)
do not ignore errors on SMBNTEncrypt in SMB Tree Connect.

Reported by Coverity (CID 1226853)

Signed-off-by: Steve French <smfrench@gmail.com>
Acked-by: Shirish Pargaonkar <shirishpargaonkar@gmail.com>
Acked-by: Sachin Prabhu <sprabhu@redhat.com>
Reviewed-by: Jeff Layton <jlayton@poochiereds.net>
2015-04-01 00:01:46 -05:00