Commit graph

12874 commits

Author SHA1 Message Date
Sage Weil 3a5e14048a Btrfs: notreelog mount option
Add a 'notreelog' mount option to disable the tree log (used by fsync,
O_SYNC writes).  This is much slower, but the tree logging produces
inconsistent views into the FS for ceph.

Signed-off-by: Sage Weil <sage@newdream.net>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2009-04-02 16:49:40 -04:00
Eric Paris a9572a15a8 Btrfs: introduce btrfs_show_options
btrfs options can change at times other than mount, yet /proc/mounts shows the
options string used when the fs was mounted (an example would be when btrfs
determines that barriers aren't useful and turns them off.)  This patch
instead outputs the actual options in use by btrfs.

Signed-off-by: Eric Paris <eparis@redhat.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2009-04-02 16:46:06 -04:00
Chris Mason fa9c0d795f Btrfs: rework allocation clustering
Because btrfs is copy-on-write, we end up picking new locations for
blocks very often.  This makes it fairly difficult to maintain perfect
read patterns over time, but we can at least do some optimizations
for writes.

This is done today by remembering the last place we allocated and
trying to find a free space hole big enough to hold more than just one
allocation.  The end result is that we tend to write sequentially to
the drive.

This happens all the time for metadata and it happens for data
when mounted -o ssd.  But, the way we record it is fairly racey
and it tends to fragment the free space over time because we are trying
to allocate fairly large areas at once.

This commit gets rid of the races by adding a free space cluster object
with dedicated locking to make sure that only one process at a time
is out replacing the cluster.

The free space fragmentation is somewhat solved by allowing a cluster
to be comprised of smaller free space extents.  This part definitely
adds some CPU time to the cluster allocations, but it allows the allocator
to consume the small holes left behind by cow.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2009-04-03 09:47:43 -04:00
Chris Mason 8e73f27501 Btrfs: Optimize locking in btrfs_next_leaf()
btrfs_next_leaf was using blocking locks when it could have been using
faster spinning ones instead.  This adds a few extra checks around
the pieces that block and switches over to spinning locks.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2009-04-03 10:14:18 -04:00
Chris Mason c8c42864f6 Btrfs: break up btrfs_search_slot into smaller pieces
btrfs_search_slot was doing too many things at once.  This breaks
it up into more reasonable units.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2009-04-03 10:14:18 -04:00
Josef Bacik 04018de5d4 Btrfs: kill the pinned_mutex
This patch removes the pinned_mutex.  The extent io map has an internal tree
lock that protects the tree itself, and since we only copy the extent io map
when we are committing the transaction we don't need it there.  We also don't
need it when caching the block group since searching through the tree is also
protected by the internal map spin lock.

Signed-off-by: Josef Bacik <jbacik@redhat.com>
2009-04-03 10:14:18 -04:00
Josef Bacik 6226cb0a5e Btrfs: kill the block group alloc mutex
This patch removes the block group alloc mutex used to protect the free space
tree for allocations and replaces it with a spin lock which is used only to
protect the free space rb tree.  This means we only take the lock when we are
directly manipulating the tree, which makes us a touch faster with
multi-threaded workloads.

This patch also gets rid of btrfs_find_free_space and replaces it with
btrfs_find_space_for_alloc, which takes the number of bytes you want to
allocate, and empty_size, which is used to indicate how much free space should
be at the end of the allocation.

It will return an offset for the allocator to use.  If we don't end up using it
we _must_ call btrfs_add_free_space to put it back.  This is the tradeoff to
kill the alloc_mutex, since we need to make sure nobody else comes along and
takes our space.

Signed-off-by: Josef Bacik <jbacik@redhat.com>
2009-04-03 10:14:18 -04:00
Josef Bacik 2552d17e32 Btrfs: clean up find_free_extent
I've replaced the strange looping constructs with a list_for_each_entry on
space_info->block_groups.  If we have a hint we just jump into the loop with
the block group and start looking for space.  If we don't find anything we
start at the beginning and start looking.  We never come out of the loop with a
ref on the block_group _unless_ we found space to use, then we drop it after we
set the trans block_group.

Signed-off-by: Josef Bacik <jbacik@redhat.com>
2009-04-03 10:14:19 -04:00
Josef Bacik 70cb074345 Btrfs: free space cache cleanups
This patch cleans up the free space cache code a bit.  It better documents the
idiosyncrasies of tree_search_offset and makes the code make a bit more sense.
I took out the info allocation at the start of __btrfs_add_free_space and put it
where it makes more sense.  This was left over cruft from when alloc_mutex
existed.  Also all of the re-searches we do to make sure we inserted properly.

Signed-off-by: Josef Bacik <jbacik@redhat.com>
2009-04-03 10:14:19 -04:00
Chris Mason bedf762ba3 Btrfs: unplug in the async bio submission threads
Btrfs pages being written get set to writeback, and then may go through
a number of steps before they hit the block layer.  This includes compression,
checksumming and async bio submission.

The end result is that someone who writes a page and then does
wait_on_page_writeback is likely to unplug the queue before the bio they
cared about got there.

We could fix this by marking bios sync, or by doing more frequent unplugs,
but this commit just changes the async bio submission code to unplug
after it has processed all the bios for a device.  The async bio submission
does a fair job of collection bios, so this shouldn't be a huge problem
for reducing merging at the elevator.

For streaming O_DIRECT writes on a 5 drive array, it boosts performance
from 386MB/s to 460MB/s.

Thanks to Hisashi Hifumi for helping with this work.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2009-04-03 10:32:58 -04:00
Chris Mason b765ead57d Btrfs: keep processing bios for a given bdev if our proc is batching
Btrfs uses async helper threads to submit write bios so the checksumming
helper threads don't block on the disk.

The submit bio threads may process bios for more than one block device,
so when they find one device congested they try to move on to other
devices instead of blocking in get_request_wait for one device.

This does a pretty good job of keeping multiple devices busy, but the
congested flag has a number of problems.  A congested device may still
give you a request, and other procs that aren't backing off the congested
device may starve you out.

This commit uses the io_context stored in current to decide if our process
has been made a batching process by the block layer.  If so, it keeps
sending IO down for at least one batch.  This helps make sure we do
a good amount of work each time we visit a bdev, and avoids large IO
stalls in multi-device workloads.

It's also very ugly.  A better solution is in the works with Jens Axboe.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2009-04-03 10:27:10 -04:00
Chris Mason d57e62b897 Btrfs: try to free metadata pages when we free btree blocks
COW means we cycle though blocks fairly quickly, and once we
free an extent on disk, it doesn't make much sense to keep the pages around.

This commit tries to immediately free the page when we free the extent,
which lowers our memory footprint significantly.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2009-03-31 14:27:58 -04:00
Chris Mason 5a3f23d515 Btrfs: add extra flushing for renames and truncates
Renames and truncates are both common ways to replace old data with new
data.  The filesystem can make an effort to make sure the new data is
on disk before actually replacing the old data.

This is especially important for rename, which many application use as
though it were atomic for both the data and the metadata involved.  The
current btrfs code will happily replace a file that is fully on disk
with one that was just created and still has pending IO.

If we crash after transaction commit but before the IO is done, we'll end
up replacing a good file with a zero length file.  The solution used
here is to create a list of inodes that need special ordering and force
them to disk before the commit is done.  This is similar to the
ext3 style data=ordering, except it is only done on selected files.

Btrfs is able to get away with this because it does not wait on commits
very often, even for fsync (which use a sub-commit).

For renames, we order the file when it wasn't already
on disk and when it is replacing an existing file.  Larger files
are sent to filemap_flush right away (before the transaction handle is
opened).

For truncates, we order if the file goes from non-zero size down to
zero size.  This is a little different, because at the time of the
truncate the file has no dirty bytes to order.  But, we flag the inode
so that it is added to the ordered list on close (via release method).  We
also immediately add it to the ordered list of the current transaction
so that we can try to flush down any writes the application sneaks in
before commit.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2009-03-31 14:27:58 -04:00
Chris Mason 1a81af4d1d Btrfs: make sure btrfs_update_delayed_ref doesn't increase ref_mod
btrfs_update_delayed_ref is optimized to add and remove different
references in one pass through the delayed ref tree.  It is a zero
sum on the total number of refs on a given extent.

But, the code was recording an extra ref in the head node.  This
never made it down to the disk but was used when deciding if it was
safe to free the extent while dropping snapshots.

The fix used here is to make sure the ref_mod count is unchanged
on the head ref when btrfs_update_delayed_ref is called.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2009-03-25 09:55:11 -04:00
Chris Mason af4176b49c Btrfs: optimize fsyncs on old files
The fsync log has code to make sure all of the parents of a file are in the
log along with the file.  It uses a minimal log of the parent directory
inodes, just enough to get the parent directory on disk.

If the transaction that originally created a file is fully on disk,
and the file hasn't been renamed or linked into other directories, we
can safely skip the parent directory walk.  We know the file is on disk
somewhere and we can go ahead and just log that single file.

This is more important now because unrelated unlinks in the parent directory
might make us force a commit if we try to log the parent.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2009-03-24 16:14:52 -04:00
Chris Mason 12fcfd22fe Btrfs: tree logging unlink/rename fixes
The tree logging code allows individual files or directories to be logged
without including operations on other files and directories in the FS.
It tries to commit the minimal set of changes to disk in order to
fsync the single file or directory that was sent to fsync or O_SYNC.

The tree logging code was allowing files and directories to be unlinked
if they were part of a rename operation where only one directory
in the rename was in the fsync log.  This patch adds a few new rules
to the tree logging.

1) on rename or unlink, if the inode being unlinked isn't in the fsync
log, we must force a full commit before doing an fsync of the directory
where the unlink was done.  The commit isn't done during the unlink,
but it is forced the next time we try to log the parent directory.

Solution: record transid of last unlink/rename per directory when the
directory wasn't already logged.  For renames this is only done when
renaming to a different directory.

mkdir foo/some_dir
normal commit
rename foo/some_dir foo2/some_dir
mkdir foo/some_dir
fsync foo/some_dir/some_file

The fsync above will unlink the original some_dir without recording
it in its new location (foo2).  After a crash, some_dir will be gone
unless the fsync of some_file forces a full commit

2) we must log any new names for any file or dir that is in the fsync
log.  This way we make sure not to lose files that are unlinked during
the same transaction.

2a) we must log any new names for any file or dir during rename
when the directory they are being removed from was logged.

2a is actually the more important variant.  Without the extra logging
a crash might unlink the old name without recreating the new one

3) after a crash, we must go through any directories with a link count
of zero and redo the rm -rf

mkdir f1/foo
normal commit
rm -rf f1/foo
fsync(f1)

The directory f1 was fully removed from the FS, but fsync was never
called on f1, only its parent dir.  After a crash the rm -rf must
be replayed.  This must be able to recurse down the entire
directory tree.  The inode link count fixup code takes care of the
ugly details.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2009-03-24 16:14:52 -04:00
Chris Mason a74ac32207 Btrfs: Make sure i_nlink doesn't hit zero too soon during log replay
During log replay, inodes are copied from the log to the main filesystem
btrees.  Sometimes they have a zero link count in the log but they actually
gain links during the replay or have some in the main btree.

This patch updates the link count to be at least one after copying the
inode out of the log.  This makes sure the inode is deleted during an
iput while the rest of the replay code is still working on it.

The log replay has fixup code to make sure that link counts are correct
at the end of the replay, so we could use any non-zero number here and
it would work fine.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2009-03-24 16:14:51 -04:00
Chris Mason a4b6e07d1a Btrfs: limit balancing work while flushing delayed refs
The delayed reference mechanism is responsible for all updates to the
extent allocation trees, including those updates created while processing
the delayed references.

This commit tries to limit the amount of work that gets created during
the final run of delayed refs before a commit.  It avoids cowing new blocks
unless it is required to finish the commit, and so it avoids new allocations
that were not really required.

The goal is to avoid infinite loops where we are always making more work
on the final run of delayed refs.  Over the long term we'll make a
special log for the last delayed ref updates as well.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2009-03-24 16:14:51 -04:00
Chris Mason 5d13a98f3b Btrfs: readahead checksums during btrfs_finish_ordered_io
This reads in blocks in the checksum btree before starting the
transaction in btrfs_finish_ordered_io.  It makes it much more likely
we'll be able to do operations inside the transaction without
needing any btree reads, which limits transaction latencies overall.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2009-03-24 16:14:51 -04:00
Chris Mason b9473439d3 Btrfs: leave btree locks spinning more often
btrfs_mark_buffer dirty would set dirty bits in the extent_io tree
for the buffers it was dirtying.  This may require a kmalloc and it
was not atomic.  So, anyone who called btrfs_mark_buffer_dirty had to
set any btree locks they were holding to blocking first.

This commit changes dirty tracking for extent buffers to just use a flag
in the extent buffer.  Now that we have one and only one extent buffer
per page, this can be safely done without losing dirty bits along the way.

This also introduces a path->leave_spinning flag that callers of
btrfs_search_slot can use to indicate they will properly deal with a
path returned where all the locks are spinning instead of blocking.

Many of the btree search callers now expect spinning paths,
resulting in better btree concurrency overall.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2009-03-24 16:14:28 -04:00
Chris Mason 89573b9c51 Btrfs: Only let very young transactions grow during commit
Commits are fairly expensive, and so btrfs has code to sit around for a while
during the commit and let new writers come in.

But, while we're sitting there, new delayed refs might be added, and those
can be expensive to process as well.  Unless the transaction is very very
young, it makes sense to go ahead and let the commit finish without hanging
around.

The commit grow loop isn't as important as it used to be, the fsync logging
code handles most performance critical syncs now.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2009-03-24 16:14:28 -04:00
Chris Mason 66d7e85ea7 Btrfs: Check for a blocking lock before taking the spin
This reduces contention on the extent buffer spin locks by testing for a
blocking lock before trying to take the spinlock.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2009-03-24 16:14:27 -04:00
Chris Mason 7f366cfecf Btrfs: reduce stack in cow_file_range
The fs/btrfs/inode.c code to run delayed allocation during writout
needed some stack usage optimization.  This is the first pass, it does
the check for compression earlier on, which allows us to do the common
(no compression) case higher up in the call chain.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2009-03-24 16:14:27 -04:00
Chris Mason b7ec40d784 Btrfs: reduce stalls during transaction commit
To avoid deadlocks and reduce latencies during some critical operations, some
transaction writers are allowed to jump into the running transaction and make
it run a little longer, while others sit around and wait for the commit to
finish.

This is a bit unfair, especially when the callers that jump in do a bunch
of IO that makes all the others procs on the box wait.  This commit
reduces the stalls this produces by pre-reading file extent pointers
during btrfs_finish_ordered_io before the transaction is joined.

It also tunes the drop_snapshot code to politely wait for transactions
that have started writing out their delayed refs to finish.  This avoids
new delayed refs being flooded into the queue while we're trying to
close off the transaction.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2009-03-24 16:14:26 -04:00
Chris Mason c3e69d58e8 Btrfs: process the delayed reference queue in clusters
The delayed reference queue maintains pending operations that need to
be done to the extent allocation tree.  These are processed by
finding records in the tree that are not currently being processed one at
a time.

This is slow because it uses lots of time searching through the rbtree
and because it creates lock contention on the extent allocation tree
when lots of different procs are running delayed refs at the same time.

This commit changes things to grab a cluster of refs for processing,
using a cursor into the rbtree as the starting point of the next search.
This way we walk smoothly through the rbtree.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2009-03-24 16:14:26 -04:00
Chris Mason 1887be66dc Btrfs: try to cleanup delayed refs while freeing extents
When extents are freed, it is likely that we've removed the last
delayed reference update for the extent.  This checks the delayed
ref tree when things are freed, and if no ref updates area left it
immediately processes the delayed ref.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2009-03-24 16:14:26 -04:00
Chris Mason 44871b1b24 Btrfs: reduce stack usage in some crucial tree balancing functions
Many of the tree balancing functions follow the same pattern.

1) cow a block
2) do something to the result

This commit breaks them up into two functions so the variables and
code required for part two don't suck down stack during part one.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2009-03-24 16:14:25 -04:00
Chris Mason 56bec294de Btrfs: do extent allocation and reference count updates in the background
The extent allocation tree maintains a reference count and full
back reference information for every extent allocated in the
filesystem.  For subvolume and snapshot trees, every time
a block goes through COW, the new copy of the block adds a reference
on every block it points to.

If a btree node points to 150 leaves, then the COW code needs to go
and add backrefs on 150 different extents, which might be spread all
over the extent allocation tree.

These updates currently happen during btrfs_cow_block, and most COWs
happen during btrfs_search_slot.  btrfs_search_slot has locks held
on both the parent and the node we are COWing, and so we really want
to avoid IO during the COW if we can.

This commit adds an rbtree of pending reference count updates and extent
allocations.  The tree is ordered by byte number of the extent and byte number
of the parent for the back reference.  The tree allows us to:

1) Modify back references in something close to disk order, reducing seeks
2) Significantly reduce the number of modifications made as block pointers
are balanced around
3) Do all of the extent insertion and back reference modifications outside
of the performance critical btrfs_search_slot code.

#3 has the added benefit of greatly reducing the btrfs stack footprint.
The extent allocation tree modifications are done without the deep
(and somewhat recursive) call chains used in the past.

These delayed back reference updates must be done before the transaction
commits, and so the rbtree is tied to the transaction.  Throttling is
implemented to help keep the queue of backrefs at a reasonable size.

Since there was a similar mechanism in place for the extent tree
extents, that is removed and replaced by the delayed reference tree.

Yan Zheng <yan.zheng@oracle.com> helped review and fixup this code.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2009-03-24 16:14:25 -04:00
Chris Mason 9fa8cfe706 Btrfs: don't preallocate metadata blocks during btrfs_search_slot
In order to avoid doing expensive extent management with tree locks held,
btrfs_search_slot will preallocate tree blocks for use by COW without
any tree locks held.

A later commit moves all of the extent allocation work for COW into
a delayed update mechanism, and this preallocation will no longer be
required.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2009-03-24 16:14:25 -04:00
Gertjan van Wingerde f762dd6821 Update my email address
Update all previous incarnations of my email address to the correct one.

Signed-off-by: Gertjan van Wingerde <gwingerde@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-03-22 11:28:37 -07:00
Tyler Hicks 2aac0cf886 eCryptfs: NULL crypt_stat dereference during lookup
If ecryptfs_encrypted_view or ecryptfs_xattr_metadata were being
specified as mount options, a NULL pointer dereference of crypt_stat
was possible during lookup.

This patch moves the crypt_stat assignment into
ecryptfs_lookup_and_interpose_lower(), ensuring that crypt_stat
will not be NULL before we attempt to dereference it.

Thanks to Dan Carpenter and his static analysis tool, smatch, for
finding this bug.

Signed-off-by: Tyler Hicks <tyhicks@linux.vnet.ibm.com>
Acked-by: Dustin Kirkland <kirkland@canonical.com>
Cc: Dan Carpenter <error27@gmail.com>
Cc: Serge Hallyn <serue@us.ibm.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-03-22 11:20:43 -07:00
Tyler Hicks 8faece5f90 eCryptfs: Allocate a variable number of pages for file headers
When allocating the memory used to store the eCryptfs header contents, a
single, zeroed page was being allocated with get_zeroed_page().
However, the size of an eCryptfs header is either PAGE_CACHE_SIZE or
ECRYPTFS_MINIMUM_HEADER_EXTENT_SIZE (8192), whichever is larger, and is
stored in the file's private_data->crypt_stat->num_header_bytes_at_front
field.

ecryptfs_write_metadata_to_contents() was using
num_header_bytes_at_front to decide how many bytes should be written to
the lower filesystem for the file header.  Unfortunately, at least 8K
was being written from the page, despite the chance of the single,
zeroed page being smaller than 8K.  This resulted in random areas of
kernel memory being written between the 0x1000 and 0x1FFF bytes offsets
in the eCryptfs file headers if PAGE_SIZE was 4K.

This patch allocates a variable number of pages, calculated with
num_header_bytes_at_front, and passes the number of allocated pages
along to ecryptfs_write_metadata_to_contents().

Thanks to Florian Streibelt for reporting the data leak and working with
me to find the problem.  2.6.28 is the only kernel release with this
vulnerability.  Corresponds to CVE-2009-0787

Signed-off-by: Tyler Hicks <tyhicks@linux.vnet.ibm.com>
Acked-by: Dustin Kirkland <kirkland@canonical.com>
Reviewed-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Eugene Teo <eugeneteo@kernel.sg>
Cc: Greg KH <greg@kroah.com>
Cc: dann frazier <dannf@dannf.org>
Cc: Serge E. Hallyn <serue@us.ibm.com>
Cc: Florian Streibelt <florian@f-streibelt.de>
Cc: stable@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-03-22 11:20:43 -07:00
Jeff Moyer 65c24491b4 aio: lookup_ioctx can return the wrong value when looking up a bogus context
The libaio test harness turned up a problem whereby lookup_ioctx on a
bogus io context was returning the 1 valid io context from the list
(harness/cases/3.p).

Because of that, an extra put_iocontext was done, and when the process
exited, it hit a BUG_ON in the put_iocontext macro called from exit_aio
(since we expect a users count of 1 and instead get 0).

The problem was introduced by "aio: make the lookup_ioctx() lockless"
(commit abf137dd77).

Thanks to Zach for pointing out that hlist_for_each_entry_rcu will not
return with a NULL tpos at the end of the loop, even if the entry was
not found.

Signed-off-by: Jeff Moyer <jmoyer@redhat.com>
Acked-by: Zach Brown <zach.brown@oracle.com>
Acked-by: Jens Axboe <jens.axboe@oracle.com>
Cc: Benjamin LaHaise <bcrl@kvack.org>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-03-19 15:57:18 -07:00
Davide Libenzi 87c3a86e1c eventfd: remove fput() call from possible IRQ context
Remove a source of fput() call from inside IRQ context.  Myself, like Eric,
wasn't able to reproduce an fput() call from IRQ context, but Jeff said he was
able to, with the attached test program.  Independently from this, the bug is
conceptually there, so we might be better off fixing it.  This patch adds an
optimization similar to the one we already do on ->ki_filp, on ->ki_eventfd.
Playing with ->f_count directly is not pretty in general, but the alternative
here would be to add a brand new delayed fput() infrastructure, that I'm not
sure is worth it.

Signed-off-by: Davide Libenzi <davidel@xmailserver.org>
Cc: Benjamin LaHaise <bcrl@kvack.org>
Cc: Trond Myklebust <trond.myklebust@fys.uio.no>
Cc: Eric Dumazet <dada1@cosmosbay.com>
Signed-off-by: Jeff Moyer <jmoyer@redhat.com>
Cc: Zach Brown <zach.brown@oracle.com>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-03-19 15:57:18 -07:00
Linus Torvalds fe2fd6cc34 Merge git://git.kernel.org/pub/scm/linux/kernel/git/mason/btrfs-unstable
* git://git.kernel.org/pub/scm/linux/kernel/git/mason/btrfs-unstable:
  Btrfs: Clear space_info full when adding new devices
  Btrfs: Fix locking around adding new space_info
2009-03-19 14:49:55 -07:00
Linus Torvalds a8e7d49aa7 Fix race in create_empty_buffers() vs __set_page_dirty_buffers()
Nick Piggin noticed this (very unlikely) race between setting a page
dirty and creating the buffers for it - we need to hold the mapping
private_lock until we've set the page dirty bit in order to make sure
that create_empty_buffers() might not build up a set of buffers without
the dirty bits set when the page is dirty.

I doubt anybody has ever hit this race (and it didn't solve the issue
Nick was looking at), but as Nick says: "Still, it does appear to solve
a real race, which we should close."

Acked-by: Nick Piggin <nickpiggin@yahoo.com.au>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-03-19 11:32:05 -07:00
Linus Torvalds 85bff8857c Merge branch 'for-2.6.29' of git://linux-nfs.org/~bfields/linux
* 'for-2.6.29' of git://linux-nfs.org/~bfields/linux:
  nfsd: nfsd should drop CAP_MKNOD for non-root
  NFSD: provide encode routine for OP_OPENATTR
2009-03-18 09:27:20 -07:00
Linus Torvalds 58cefd2b1e Merge branch 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4
* 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4:
  ext4: fix bb_prealloc_list corruption due to wrong group locking
  ext4: fix bogus BUG_ONs in in mballoc code
  ext4: Print the find_group_flex() warning only once
  ext4: fix header check in ext4_ext_search_right() for deep extent trees.
2009-03-17 20:55:40 -07:00
Benny Halevy 84f09f46b4 NFSD: provide encode routine for OP_OPENATTR
Although this operation is unsupported by our implementation
we still need to provide an encode routine for it to
merely encode its (error) status back in the compound reply.

Thanks for Bill Baker at sun.com for testing with the Sun
OpenSolaris' client, finding, and reporting this bug at
Connectathon 2009.

This bug was introduced in 2.6.27

Signed-off-by: Benny Halevy <bhalevy@panasas.com>
Cc: stable@kernel.org
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2009-03-17 14:54:45 -04:00
Linus Torvalds ee568b25ee Avoid 64-bit "switch()" statements on 32-bit architectures
Commit ee6f779b9e ("filp->f_pos not
correctly updated in proc_task_readdir") changed the proc code to use
filp->f_pos directly, rather than through a temporary variable.  In the
process, that caused the operations to be done on the full 64 bits, even
though the offset is never that big.

That's all fine and dandy per se, but for some unfathomable reason gcc
generates absolutely horrid code when using 64-bit values in switch()
statements.  To the point of actually calling out to gcc helper
functions like __cmpdi2 rather than just doing the trivial comparisons
directly the way gcc does for normal compares.  At which point we get
link failures, because we really don't want to support that kind of
crazy code.

Fix this by just casting the f_pos value to "unsigned long", which
is plenty big enough for /proc, and avoids the gcc code generation issue.

Reported-by: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Zhang Le <r0bertz@gentoo.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-03-17 10:02:35 -07:00
Eric Sandeen d33a1976fb ext4: fix bb_prealloc_list corruption due to wrong group locking
This is for Red Hat bug 490026: EXT4 panic, list corruption in
ext4_mb_new_inode_pa

ext4_lock_group(sb, group) is supposed to protect this list for
each group, and a common code flow to remove an album is like
this:

    ext4_get_group_no_and_offset(sb, pa->pa_pstart, &grp, NULL);
    ext4_lock_group(sb, grp);
    list_del(&pa->pa_group_list);
    ext4_unlock_group(sb, grp);

so it's critical that we get the right group number back for
this prealloc context, to lock the right group (the one 
associated with this pa) and prevent concurrent list manipulation.

however, ext4_mb_put_pa() passes in (pa->pa_pstart - 1) with a 
comment, "-1 is to protect from crossing allocation group".

This makes sense for the group_pa, where pa_pstart is advanced
by the length which has been used (in ext4_mb_release_context()),
and when the entire length has been used, pa_pstart has been
advanced to the first block of the next group.

However, for inode_pa, pa_pstart is never advanced; it's just
set once to the first block in the group and not moved after
that.  So in this case, if we subtract one in ext4_mb_put_pa(),
we are actually locking the *previous* group, and opening the
race with the other threads which do not subtract off the extra
block.

Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-03-16 23:25:40 -04:00
Zhang Le ee6f779b9e filp->f_pos not correctly updated in proc_task_readdir
filp->f_pos only get updated at the end of the function. Thus d_off of those
dirents who are in the middle will be 0, and this will cause a problem in
glibc's readdir implementation, specifically endless loop. Because when overflow
occurs, f_pos will be set to next dirent to read, however it will be 0, unless
the next one is the last one. So it will start over again and again.

There is a sample program in man 2 gendents. This is the output of the program
running on a multithread program's task dir before this patch is applied:

  $ ./a.out /proc/3807/task
  --------------- nread=128 ---------------
  i-node#  file type  d_reclen  d_off   d_name
    506442  directory    16          1  .
    506441  directory    16          0  ..
    506443  directory    16          0  3807
    506444  directory    16          0  3809
    506445  directory    16          0  3812
    506446  directory    16          0  3861
    506447  directory    16          0  3862
    506448  directory    16          8  3863

This is the output after this patch is applied

  $ ./a.out /proc/3807/task
  --------------- nread=128 ---------------
  i-node#  file type  d_reclen  d_off   d_name
    506442  directory    16          1  .
    506441  directory    16          2  ..
    506443  directory    16          3  3807
    506444  directory    16          4  3809
    506445  directory    16          5  3812
    506446  directory    16          6  3861
    506447  directory    16          7  3862
    506448  directory    16          8  3863

Signed-off-by: Zhang Le <r0bertz@gentoo.org>
Acked-by: Al Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-03-16 07:51:33 -07:00
Linus Torvalds 18553c38bc Merge branch 'for-linus' of git://git.kernel.dk/linux-2.6-block
* 'for-linus' of git://git.kernel.dk/linux-2.6-block:
  Fix Xilinx SystemACE driver to handle empty CF slot
  block: fix memory leak in bio_clone()
  block: Add gfp_mask parameter to bio_integrity_clone()
2009-03-14 13:43:18 -07:00
Li Zefan 059ea3318c block: fix memory leak in bio_clone()
If bio_integrity_clone() fails, bio_clone() returns NULL without freeing
the newly allocated bio.

Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2009-03-14 21:06:52 +01:00
un'ichi Nomura 87092698c6 block: Add gfp_mask parameter to bio_integrity_clone()
Stricter gfp_mask might be required for clone allocation.
For example, request-based dm may clone bio in interrupt context
so it has to use GFP_ATOMIC.

Signed-off-by: Kiyoshi Ueda <k-ueda@ct.jp.nec.com>
Signed-off-by: Jun'ichi Nomura <j-nomura@ce.jp.nec.com>
Acked-by: Martin K. Petersen <martin.petersen@oracle.com>
Cc: Alasdair G Kergon <agk@redhat.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2009-03-14 21:06:51 +01:00
Linus Torvalds f1823acfbc Merge branch 'bugfixes' of git://git.linux-nfs.org/projects/trondmy/nfs-2.6
* 'bugfixes' of git://git.linux-nfs.org/projects/trondmy/nfs-2.6:
  NFS: Fix the fix to Bugzilla #11061, when IPv6 isn't defined...
  SUNRPC: xprt_connect() don't abort the task if the transport isn't bound
  SUNRPC: Fix an Oops due to socket not set up yet...
  Bug 11061, NFS mounts dropped
  NFS: Handle -ESTALE error in access()
  NLM: Fix GRANT callback address comparison when IPv6 is enabled
  NLM: Shrink the IPv4-only version of nlm_cmp_addr()
  NFSv3: Fix posix ACL code
  NFS: Fix misparsing of nfsv4 fs_locations attribute (take 2)
  SUNRPC: Tighten up the task locking rules in __rpc_execute()
2009-03-14 12:00:18 -07:00
Linus Torvalds ff9cb43ce0 Merge branch 'upstream-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mfasheh/ocfs2
* 'upstream-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mfasheh/ocfs2:
  ocfs2: Use xs->bucket to set xattr value outside
  ocfs2: Fix a bug found by sparse check.
  ocfs2: tweak to get the maximum inline data size with xattr
  ocfs2: reserve xattr block for new directory with inline data
2009-03-14 11:59:22 -07:00
Tyler Hicks 84814d642a eCryptfs: don't encrypt file key with filename key
eCryptfs has file encryption keys (FEK), file encryption key encryption
keys (FEKEK), and filename encryption keys (FNEK).  The per-file FEK is
encrypted with one or more FEKEKs and stored in the header of the
encrypted file.  I noticed that the FEK is also being encrypted by the
FNEK.  This is a problem if a user wants to use a different FNEK than
their FEKEK, as their file contents will still be accessible with the
FNEK.

This is a minimalistic patch which prevents the FNEKs signatures from
being copied to the inode signatures list.  Ultimately, it keeps the FEK
from being encrypted with a FNEK.

Signed-off-by: Tyler Hicks <tyhicks@linux.vnet.ibm.com>
Cc: Serge Hallyn <serue@us.ibm.com>
Acked-by: Dustin Kirkland <kirkland@canonical.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-03-14 11:57:22 -07:00
Johannes Weiner 15e7b87676 nommu: ramfs: don't leak pages when adding to page cache fails
When a ramfs nommu mapping is expanded, contiguous pages are allocated
and added to the pagecache.  The caller's reference is then passed on
by moving whole pagevecs to the file lru list.

If the page cache adding fails, make sure that the error path also
moves the pagevec contents which might still contain up to PAGEVEC_SIZE
successfully added pages, of which we would leak references otherwise.

Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: David Howells <dhowells@redhat.com>
Cc: Enrik Berkhan <Enrik.Berkhan@ge.com>
Cc: Nick Piggin <nickpiggin@yahoo.com.au>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-03-14 11:57:22 -07:00
Enrik Berkhan 020fe22ff1 nommu: ramfs: pages allocated to an inode's pagecache may get wrongly discarded
The pages attached to a ramfs inode's pagecache by truncation from nothing
- as done by SYSV SHM for example - may get discarded under memory
pressure.

The problem is that the pages are not marked dirty.  Anything that creates
data in an MMU-based ramfs will cause the pages holding that data will
cause the set_page_dirty() aop to be called.

For the NOMMU-based mmap, set_page_dirty() may be called by write(), but
it won't be called by page-writing faults on writable mmaps, and it isn't
called by ramfs_nommu_expand_for_mapping() when a file is being truncated
from nothing to allocate a contiguous run.

The solution is to mark the pages dirty at the point of allocation by the
truncation code.

Signed-off-by: Enrik Berkhan <Enrik.Berkhan@ge.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Nick Piggin <nickpiggin@yahoo.com.au>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-03-14 11:57:22 -07:00