Since commit 7e790dd5fc ("inotify: fix
error paths in inotify_update_watch") inotify changed the manor in which
it gave watch descriptors back to userspace. Previous to this commit
inotify acted like the following:
inotify_add_watch(X, Y, Z) = 1
inotify_rm_watch(X, 1);
inotify_add_watch(X, Y, Z) = 2
but after this patch inotify would return watch descriptors like so:
inotify_add_watch(X, Y, Z) = 1
inotify_rm_watch(X, 1);
inotify_add_watch(X, Y, Z) = 1
which I saw as equivalent to opening an fd where
open(file) = 1;
close(1);
open(file) = 1;
seemed perfectly reasonable. The issue is that quite a bit of userspace
apparently relies on the behavior in which watch descriptors will not be
quickly reused. KDE relies on it, I know some selinux packages rely on
it, and I have heard complaints from other random sources such as debian
bug 558981.
Although the man page implies what we do is ok, we broke userspace so
this patch almost reverts us to the old behavior. It is still slightly
racey and I have patches that would fix that, but they are rather large
and this will fix it for all real world cases. The race is as follows:
- task1 creates a watch and blocks in idr_new_watch() before it updates
the hint.
- task2 creates a watch and updates the hint.
- task1 updates the hint with it's older wd
- task removes the watch created by task2
- task adds a new watch and will reuse the wd originally given to task2
it requires moving some locking around the hint (last_wd) but this should
solve it for the real world and be -stable safe.
As a side effect this patch papers over a bug in the lib/idr code which
is causing a large number WARN's to pop on people's system and many
reports in kerneloops.org. I'm working on the root cause of that idr
bug seperately but this should make inotify immune to that issue.
Signed-off-by: Eric Paris <eparis@redhat.com>
Cc: stable@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Move xfsbdstrat and xfs_bdstrat_cb from xfs_lrw.c and xfs_bioerror
and xfs_bioerror_relse from xfs_rw.c into xfs_buf.c. This also
means xfs_bioerror and xfs_bioerror_relse can be marked static now.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
Fold XFS_bwrite into it's only caller, xfs_bwrite and move it into
xfs_buf.c instead of leaving it as a fairly large inline function.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
Don't bother using XFS_bwrite as it doesn't provide much code for
our use case. Instead opencode it and fold xlog_bdstrat_cb into the
new xlog_bdstrat helper.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
Now that the perag structure is allocated memory rather than held in
an array, we don't need to have the busy extent array external to
the structure. Embed it into the perag structure to avoid needing an
extra allocation when setting up.
Signed-off-by: Dave Chinner <david@fromorbit.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
Add proper error handling in case an error occurs while initializing
new perag structures for a mount point. The mount structure is
restored to its previous state by deleting and freeing any perag
structures added during the call.
Signed-off-by: Dave Chinner <david@fromorbit.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
The filestreams cache flush is not needed in the sync code as it
does not affect data writeback, and it is now not used by the growfs
code, either, so kill it.
Signed-off-by: Dave Chinner <david@fromorbit.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
Uninline xfs_perag_{get,put} so that tracepoints can be inserted
into them to speed debugging of reference count problems.
Signed-off-by: Dave Chinner <david@fromorbit.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
Reference count the per-ag structures to ensure that we keep get/put
pairs balanced. Assert that the reference counts are zero at unmount
time to catch leaks. In future, reference counts will enable us to
safely remove perag structures by allowing us to detect when they
are no longer in use.
Signed-off-by: Dave Chinner <david@fromorbit.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
The use of an array for the per-ag structures requires reallocation
of the array when growing the filesystem. This requires locking
access to the array to avoid use after free situations, and the
locking is difficult to get right. To avoid needing to reallocate an
array, change the per-ag structures to an allocated object per ag
and index them using a tree structure.
The AGs are always densely indexed (hence the use of an array), but
the number supported is 2^32 and lookups tend to be random and hence
indexing needs to scale. A simple choice is a radix tree - it works
well with this sort of index. This change also removes another
large contiguous allocation from the mount/growfs path in XFS.
The growing process now needs to change to only initialise the new
AGs required for the extra space, and as such only needs to
exclusively lock the tree for inserts. The rest of the code only
needs to lock the tree while doing lookups, and hence this will
remove all the deadlocks that currently occur on the m_perag_lock as
it is now an innermost lock. The lock is also changed to a spinlock
from a read/write lock as the hold time is now extremely short.
To complete the picture, the per-ag structures will need to be
reference counted to ensure that we don't free/modify them while
they are still in use. This will be done in subsequent patch.
Signed-off-by: Dave Chinner <david@fromorbit.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
Convert the remaining direct lookups of the per ag structures to use
get/put accesses. Ensure that the loops across AGs and prior users
of the interface balance gets and puts correctly.
Signed-off-by: Dave Chinner <david@fromorbit.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
Use xfs_perag_get() and xfs_perag_put() in the filestreams code.
Signed-off-by: Dave Chinner <david@fromorbit.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
Start abstracting the perag references so that the indexing of the
structures is not directly coded into all the places that uses the
perag structures. This will allow us to separate the use of the
perag structure and the way it is indexed and hence avoid the known
deadlocks related to growing a busy filesystem.
Signed-off-by: Dave Chinner <david@fromorbit.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
xfs_get_perag is really getting the perag that an inode belongs to
based on it's inode number. Convert the use of this function to just
get the perag from a provided ag number. Use this new function to
obtain the per-ag structure when traversing the per AG inode trees
for sync and reclaim.
Signed-off-by: Dave Chinner <david@fromorbit.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
The xfsbufd wakes every xfsbufd_centisecs (once per second by
default) for each filesystem even when the filesystem is idle. If
the xfsbufd has nothing to do, put it into a long term sleep and
only wake it up when there is work pending (i.e. dirty buffers to
flush soon). This will make laptop power misers happy.
Signed-off-by: Dave Chinner <david@fromorbit.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
Now that the AIL push algorithm is traversal safe, we don't need a
watchdog function in the xfsaild to catch pushes that fail to make
progress. Remove the watchdog timeout and make pushes purely driven
by demand. This will remove the once-per-second wakeup that is seen
when the filesystem is idle and make laptop power misers happy.
Signed-off-by: Dave Chinner <david@fromorbit.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
Remove the roll-your-own linked list operations.
Signed-off-by: Dave Chinner <david@fromorbit.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
Just minor housekeeping, a lot more functions can be trivially made
static; others could if we reordered things a bit...
Signed-off-by: Eric Sandeen <sandeen@sandeen.net>
Signed-off-by: Alex Elder <aelder@sgi.com>
The swap extent ioctl passes in a target inode and a temporary inode
which are clearly named in the ioctl structure. The code then
assigns temp to target and vice versa, making it extremely difficult
to work out which inode is which later in the code. Make this
consistent throughout the code.
Also make xfs_swap_extent static as there are no external users of
the function.
Signed-off-by: Dave Chinner <david@fromorbit.com>
Signed-off-by: Alex Elder <aelder@sgi.com>
To be able to diagnose whether the swap extents function is
detecting compatible inode data fork configurations for swapping
extents, add tracing points to the code to allow us to see the
format of the inode forks before and after the swap.
Signed-off-by: Dave Chinner <david@fromorbit.com>
Signed-off-by: Alex Elder <aelder@sgi.com>
When swapping extents, we can corrupt inodes by swapping data forks
that are in incompatible formats. This is caused by the two indoes
having different fork offsets due to the presence of an attribute
fork on an attr2 filesystem. xfs_fsr tries to be smart about
setting the fork offset, but the trick it plays only works on attr1
(old fixed format attribute fork) filesystems.
Changing the way xfs_fsr sets up the attribute fork will prevent
this situation from ever occurring, so in the kernel code we can get
by with a preventative fix - check that the data fork in the
defragmented inode is in a format valid for the inode it is being
swapped into. This will lead to files that will silently and
potentially repeatedly fail defragmentation, so issue a warning to
the log when this particular failure occurs to let us know that
xfs_fsr needs updating/fixing.
To help identify how to improve xfs_fsr to avoid this issue, add
trace points for the inodes being swapped so that we can determine
why the swap was rejected and to confirm that the code is making the
right decisions and modifications when swapping forks.
A further complication is even when the swap is allowed to proceed
when the fork offset is different between the two inodes then value
for the maximum number of extents the data fork can hold can be
wrong. Make sure these are also set correctly after the swap occurs.
Signed-off-by: Dave Chinner <david@fromorbit.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
When xfs_rtfind_forw() returns an error, the block is returned
uninitialised. xfs_rtfree_range() is not checking the error return,
so could be using an uninitialised block number for modifying bitmap
summary info.
The problem was found by gcc when compiling the *userspace* libxfs
code - it is an copy of the kernel code with the exact same bug.
gcc gives an uninitialised variable warning on the userspace code
but not on the kernel code. You gotta love the consistency (Mmmm,
slightly chewy today!).
Signed-off-by: Dave Chinner <david@fromorbit.com>
Signed-off-by: Alex Elder <aelder@sgi.com>
When reclaiming stale inodes, we need to guarantee that inodes are
unpinned before returning with a "clean" status. If we don't we can
reclaim inodes that are pinned, leading to use after free in the
transaction subsystem as transactions complete.
Signed-off-by: Dave Chinner <david@fromorbit.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
lockdep complains about a the lock not being initialised as we do an
ASSERT based check that the lock is not held before we initialise it
to catch inodes freed with the lock held.
lockdep does this check for us in the lock initialisation code, so
remove the ASSERT to stop the lockdep warning.
Signed-off-by: Dave Chinner <david@fromorbit.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
We cannot do direct inode reclaim without taking the flush lock to
ensure that we do not reclaim an inode under IO. We check the inode
is clean before doing direct reclaim, but this is not good enough
because the inode flush code marks the inode clean once it has
copied the in-core dirty state to the backing buffer.
It is the flush lock that determines whether the inode is still
under IO, even though it is marked clean, and the inode is still
required at IO completion so we can't reclaim it even though it is
clean in core. Hence the requirement that we need to take the flush
lock even on clean inodes because this guarantees that the inode
writeback IO has completed and it is safe to reclaim the inode.
With delayed write inode flushing, we coul dend up waiting a long
time on the flush lock even for a clean inode. The background
reclaim already handles this efficiently, so avoid all the problems
by killing the direct reclaim path altogether.
Signed-off-by: Dave Chinner <david@fromorbit.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
The reclaim code will handle flushing of dirty inodes before reclaim
occurs, so avoid them when determining whether an inode is a
candidate for flushing to disk when walking the radix trees. This
is based on a test patch from Christoph Hellwig.
Signed-off-by: Dave Chinner <david@fromorbit.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
Make the inode tree reclaim walk exclusive to avoid races with
concurrent sync walkers and lookups. This is a version of a patch
posted by Christoph Hellwig that avoids all the code duplication.
Signed-off-by: Dave Chinner <david@fromorbit.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
We should update reserve space if it is delalloc buffer
and that is indicated by EXT4_GET_BLOCKS_DELALLOC_RESERVE flag.
So use EXT4_GET_BLOCKS_DELALLOC_RESERVE in place of
EXT4_GET_BLOCKS_UPDATE_RESERVE_SPACE
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
When we fallocate a region of the file which we had recently written,
and which is still in the page cache marked as delayed allocated blocks
we need to make sure we don't do the quota update on writepage path.
This is because the needed quota updated would have already be done
by fallocate.
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
We need to release the journal before we do a write_inode. Otherwise
we could deadlock.
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Instead of playing sick games with path saving, cleanups, just retry
the entire thing once with LOOKUP_REVAL added. Post-.34 we'll convert
all -ESTALE handling in there to that style, rather than playing with
many retry loops deep in the call chain.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
If ->follow_link handler return the error, it should decrement
nd->path refcnt. But, ecryptfs_follow_link() doesn't decrement.
This patch fix it by using usual nd_set_link() style error handling,
instead of playing with nd->path.
Signed-off-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
commit 5300990c03 had stepped on a rather
nasty mess: definitions of ACC_MODE used to be different. Fixed the
resulting breakage, converting them to variant that takes O_... value;
all callers have that and it actually simplifies life (see tomoyo part
of changes).
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
For symlinks generic_readlink() will work just fine and for directories
we don't want ->readlink() at all.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
We end up trying to kfree() nd.last.name on open("/mnt/tmp", O_CREAT)
if /mnt/tmp is an autofs direct mount. The reason is that nd.last_type
is bogus here; we want LAST_BIND for everything of that kind and we
get LAST_NORM left over from finding parent directory.
So make sure that it *is* set properly; set to LAST_BIND before
doing ->follow_link() - for normal symlinks it will be changed
by __vfs_follow_link() and everything else needs it set that way.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Instead of opencoding the fsync calling sequence use vfs_fsync. This also
gets rid of the useless i_mutex over the data writeout.
Consolidate the remaining special code for syncing directories and document
it's quirks.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Since we're checking for LAST_NFS4_OP, use FIRST_NFS4_OP to be consistent.
Signed-off-by: Ricardo Labiaga <Ricardo.Labiaga@netapp.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
The server incorrectly assumes that the operations in the
array start with value 0. The first operation (OP_ACCESS)
has a value of 3, causing the check in nfsd4_decode_compound
to be off.
Instead of comparing that the operation number is less than
the number of elements in the array, the server should verify
that it is less than the maximum valid operation number
defined by LAST_NFS4_OP.
Signed-off-by: Ricardo Labiaga <Ricardo.Labiaga@netapp.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
There are two copies of list_sort() in the tree already, one in the DRM
code, another in ubifs. Now XFS needs this as well. Create a generic
list_sort() function from the ubifs version and convert existing users
to it so we don't end up with yet another copy in the tree.
Signed-off-by: Dave Chinner <david@fromorbit.com>
Acked-by: Dave Airlie <airlied@redhat.com>
Acked-by: Artem Bityutskiy <dedekind@infradead.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
If ->follow_link handler return the error, it should decrement
nd->path refcnt.
This patch fix it.
Signed-off-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
If ->follow_link handler returns an error, it should decrement
nd->path refcnt. But ocfs2_fast_follow_link() doesn't decrement.
This patch fixes the problem by using nd_set_link() style error handling
instead of playing with nd->path.
Signed-off-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Signed-off-by: Joel Becker <joel.becker@oracle.com>
* 'for-linus' of git://oss.sgi.com/xfs/xfs:
xfs: Ensure we force all busy extents in range to disk
xfs: Don't flush stale inodes
xfs: fix timestamp handling in xfs_setattr
xfs: use DECLARE_EVENT_CLASS
* git://git.kernel.org/pub/scm/linux/kernel/git/steve/gfs2-2.6-fixes:
GFS2: Use MAX_LFS_FILESIZE for meta inode size
GFS2: Fix gfs2_xattr_acl_chmod()
GFS2: Fix locking bug in rename
GFS2: Ensure uptodate inode size when using O_APPEND
A long time ago we regarded zero page as file_rss and vm_normal_page
doesn't return NULL.
But now, we reinstated ZERO_PAGE and vm_normal_page's implementation can
return NULL in case of zero page. Also we don't count it with file_rss
any more.
Then, RSS and PSS can't be matched. For consistency, Let's ignore zero
page in smaps_pte_range.
Signed-off-by: Minchan Kim <minchan.kim@gmail.com>
Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Acked-by: Hugh Dickins <hugh.dickins@tiscali.co.uk>
Acked-by: Matt Mackall <mpm@selenic.com>
Reviewed-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Commit d899bf7b (procfs: provide stack information for threads) introduced
to show stack information in /proc/{pid}/status. But it cause large
performance regression. Unfortunately /proc/{pid}/status is used ps
command too and ps is one of most important component. Because both to
take mmap_sem and page table walk are heavily operation.
If many process run, the ps performance is,
[before d899bf7b]
% perf stat ps >/dev/null
Performance counter stats for 'ps':
4090.435806 task-clock-msecs # 0.032 CPUs
229 context-switches # 0.000 M/sec
0 CPU-migrations # 0.000 M/sec
234 page-faults # 0.000 M/sec
8587565207 cycles # 2099.425 M/sec
9866662403 instructions # 1.149 IPC
3789415411 cache-references # 926.409 M/sec
30419509 cache-misses # 7.437 M/sec
128.859521955 seconds time elapsed
[after d899bf7b]
% perf stat ps > /dev/null
Performance counter stats for 'ps':
4305.081146 task-clock-msecs # 0.028 CPUs
480 context-switches # 0.000 M/sec
2 CPU-migrations # 0.000 M/sec
237 page-faults # 0.000 M/sec
9021211334 cycles # 2095.480 M/sec
10605887536 instructions # 1.176 IPC
3612650999 cache-references # 839.160 M/sec
23917502 cache-misses # 5.556 M/sec
152.277819582 seconds time elapsed
Thus, this patch revert it. Fortunately /proc/{pid}/task/{tid}/smaps
provide almost same information. we can use it.
Commit d899bf7b introduced two features:
1) Add the annotattion of [thread stack: xxxx] mark to
/proc/{pid}/task/{tid}/maps.
2) Add StackUsage field to /proc/{pid}/status.
I only revert (2), because I haven't seen (1) cause regression.
Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Stefani Seibold <stefani@seibold.net>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Randy Dunlap <randy.dunlap@oracle.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andi Kleen <andi@firstfloor.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
