Commit graph

41372 commits

Author SHA1 Message Date
Jaegeuk Kim
1b77c416e7 f2fs: use a page temporarily for encrypted gced page
That encrypted page is used temporarily, so we don't need to mark it accessed.

Reviewed-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-08-05 08:08:04 -07:00
Chao Yu
8f46dcaea8 f2fs: expose f2fs_write_cache_pages
If there are gced dirty pages and normal dirty pages in the mapping
of one inode, we might writeback them alternately with discontinuous
block address, resulting in low performance.

This patch introduces f2fs_write_cache_pages with codes copied from
write_cache_pages in mm/page-writeback.c.

In this function, we refactor flow with two steps:
1) writeback all cold type pages.
2) writeback all non-cold type pages.

By using this method, f2fs will writeback dirty pages with the same
temperature in bunch mode, it makes writeouted block being with
more continuous address, so they can be merged as much as possible
in f2fs bio cache, and also it will reduce the chance of submiting
small IO from block layer.

Test environment: 8g nokia sd card (very old sd card, but it shows
better effect when testing with this patch, and with a 32g kingston
sd card, I didn't see much more improvement).

Test step:
1. touch testfile;
2. truncate -s 512K testfile;
3. write all pages with odd index;
4. trigger gc by ioctl;
5. write all pages with even index;
6. time fsync testfile.

before:
real	0m0.402s
user	0m0.000s
sys	0m0.000s

after:
real	0m0.143s
user	0m0.004s
sys	0m0.004s

Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-08-04 14:09:59 -07:00
Chao Yu
037fe70c9a f2fs: correct return value of ->setxattr
This patch fixes to return correct error number of ->setxattr, which
is reported by xfstest tests/generic/026 as below:

generic/026      - output mismatch
    --- tests/generic/026.out
    +++ results/generic/026.out.bad
    @@ -4,6 +4,6 @@
     1 below acl max
     acl max
     1 above acl max
    -chacl: cannot set access acl on "largeaclfile": Argument list too long
    +chacl: cannot set access acl on "largeaclfile": Numerical result out of range
     use 16 aces
     use 17 aces
    ...
Ran: generic/026
Failures: generic/026
Failed 1 of 1 tests

Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-08-04 14:09:59 -07:00
Chao Yu
bd936f8407 f2fs: cleanup write_orphan_inodes
Previously, since 'commit 4531929e39 ("f2fs: move grabing orphan
pages out of protection region")' was committed, in write_orphan_inodes(),
we will grab all meta page in a batch before we use them under spinlock,
so that we can avoid large time delay of grabbing meta pages under
spinlock.

Now, 'commit d6c67a4fee ("f2fs: revmove spin_lock for
write_orphan_inodes")' remove the spinlock in write_orphan_inodes,
so there is no issue we describe above, we'd better recover to move
the grab operation to original place for readability.

Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-08-04 14:09:59 -07:00
Chao Yu
5b3391244d f2fs: warm up cold page after mmaped write
With cost-benifit method, background gc will consider old section with
fewer valid blocks as candidate victim, these old blocks in section will
be treated as cold data, and laterly will be moved into cold segment.

But if the gcing page is attached by user through buffered or mmaped
write, we should reset the page as non-cold one, because this page may
have more opportunity for further updating.

So fix to add clearing code for the missed 'mmap' case.

Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-08-04 14:09:59 -07:00
Chao Yu
c1c1b58359 f2fs: add new ioctl F2FS_IOC_GARBAGE_COLLECT
When background gc is off, the only way to trigger gc is executing
a force gc in some operations who wants to grab space in disk.

The executing condition is limited: to execute force gc, we should
wait for the time when there is almost no more free section for LFS
allocation. This seems not reasonable for our user who wants to
control triggering gc by himself.

This patch introduces F2FS_IOC_GARBAGE_COLLECT interface for
triggering garbage collection by using ioctl. It provides our users
one more option to trigger gc.

Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-08-04 14:09:58 -07:00
Chao Yu
a28ef1f5ae f2fs: maintain extent cache in separated file
This patch moves extent cache related code from data.c into extent_cache.c
since extent cache is independent feature, and its codes are not relate to
others in data.c, it's better for us to maintain them in separated place.

There is no functionality change, but several small coding style fixes
including:
* rename __drop_largest_extent to f2fs_drop_largest_extent for exporting;
* rename misspelled word 'untill' to 'until';
* remove unneeded 'return' in the end of f2fs_destroy_extent_tree().

Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-08-04 14:09:58 -07:00
Fan Li
3c7df87dad f2fs: don't try to split extents shorter than F2FS_MIN_EXTENT_LEN
Since only parts of extents longer than F2FS_MIN_EXTENT_LEN will
be kept in extent cache after split, extents already shorter than
F2FS_MIN_EXTENT_LEN don't need to try split at all.

Signed-off-by: Fan Li <fanofcode.li@samsung.com>
Reviewed-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-08-04 14:09:58 -07:00
Chao Yu
90d4388ac2 f2fs: fix to update page flag
This patch fixes to update page flag (e.g. Uptodate/cold flag) in
->write_begin.

Otherwise, page will be non-uptodate when we try to write entire
page, and cold data flag in page will not be clean when gced page
is being rewritten.

Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-08-04 14:09:57 -07:00
Jaegeuk Kim
7023a1ad17 f2fs: shrink unreferenced extent_caches first
If an extent_tree entry has a zero reference count, we can drop it from the
cache in higher priority rather than currently referencing entries.

Reviewed-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-08-04 14:09:57 -07:00
Chao Yu
bb96a8d51e f2fs: enhance multithread performance
In ->writepages, we use writepages mutex lock to serialize all block
address allocation and page submitting pairs from different inodes.
This method makes our delayed dirty pages of one inode being written
continously as many as possible.

But there is one problem that we did not submit current cached bio in
protection region of writepages mutex lock, so there is a small chance
that we submit the one of other thread's as below, resulting in
splitting more bios.

thread 1			thread 2
->writepages
  lock(writepages)
  ->write_cache_pages
  unlock(writepages)
				  lock(writepages)
				  ->write_cache_pages
  ->f2fs_submit_merged_bio
				    ->writepage
				  unlock(writepages)

fs_mark-6535  [002] ....  2242.270230: f2fs_submit_write_bio: dev = (1,0), WRITE_SYNC, DATA, sector = 5766152, size = 524288
fs_mark-6536  [000] ....  2242.270361: f2fs_submit_write_bio: dev = (1,0), WRITE_SYNC, DATA, sector = 5767176, size = 4096
fs_mark-6536  [000] ....  2242.270370: f2fs_submit_write_bio: dev = (1,0), WRITE_SYNC, NODE, sector = 8138112, size = 4096
fs_mark-6535  [002] ....  2242.270776: f2fs_submit_write_bio: dev = (1,0), WRITE_SYNC, DATA, sector = 5767184, size = 516096

This may really increase time of block layer works, and may cause
larger IO lantency.

This patch moves the submitting operation into region of writepages
mutex lock to avoid bio splits when concurrently writebacking is
intensive.

my test environment: virtual machine,
intel cpu i5 2500, 8GB size memory, 4GB size ramdisk

time fs_mark  -t  16  -L  1  -s  524288  -S  1  -d  /mnt/f2fs/

before:
real	0m4.244s
user	0m0.088s
sys	0m12.336s

after:
real	0m3.822s
user	0m0.072s
sys	0m10.760s

Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-08-04 14:09:57 -07:00
Chao Yu
741a7bea79 f2fs: restrict multimedia filename
When testing with fs_mark, some blocks were written out as cold
data which were mixed with warm data, resulting in splitting more
bios.

This is because fs_mark will create file with random filename as
below:

559551ee~~~~~~~~15Z29OCC05JCKQP60JQ42MKV
559551ee~~~~~~~~NZAZ6X8OA8LHIIP6XD0L58RM
559551ef~~~~~~~~B15YDSWAK789HPSDZKYTW6WM
559551f1~~~~~~~~2DAE5DPS79785BUNTFWBEMP3
559551f1~~~~~~~~1MYDY0BKSQCJPI32Q8C514RM
559551f1~~~~~~~~YQOTMAOMN5CVRFOUNI026MP4
559551f3~~~~~~~~1WF42LPRTQJNPPGR3EINKMPE
559551f3~~~~~~~~8Y2NRK7CEPPAA02LY936PJPG

They are regarded as cold file since their filename are ended with
multimedia files' extension, but this should be wrong as we only
match the extension of filename, not the whole one.

In this patch, we try to fix the format of multimedia filename to:
"filename + '.' + extension", then we set cold file only its
filename matches the format.

So after this change, it will reduce the probability we set the
wrong cold file, also it helps a little for fs_mark's performance
on f2fs.

Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-08-04 14:09:57 -07:00
Nicholas Krause
c1079892f4 f2fs: make the function check_dnode have a return type of bool and change it's name to is_alive
This makes the function check_dnode have a return type of bool
due to this particular function only ever returning either one
or zero as its return value and changes the name of the function
to is_alive in order to better explain this function's intended
work of checking if a dnode is still in use by the filesystem.

Signed-off-by: Nicholas Krause <xerofoify@gmail.com>
[Jaegeuk Kim: change the return value check for the renamed function]
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-08-04 14:09:56 -07:00
Jaegeuk Kim
84bc926c07 f2fs: check the largest extent at look-up time
Because of the extent shrinker or other -ENOMEM scenarios, it cannot guarantee
that the largest extent would be cached in the tree all the time.

Instead of relying on extent_tree, we can simply check the cached one in extent
tree accordingly.

Reviewed-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-08-04 14:09:56 -07:00
Jaegeuk Kim
3e72f72139 f2fs: use extent_cache by default
We don't need to handle the duplicate extent information.

The integrated rule is:
 - update on-disk extent with largest one tracked by in-memory extent_cache
 - destroy extent_tree for the truncation case
 - drop per-inode extent_cache by shrinker

Reviewed-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-08-04 14:09:56 -07:00
Jaegeuk Kim
7daaea256d f2fs: add noextent_cache mount option
This patch adds noextent_cache mount option.

Reviewed-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-08-04 14:09:55 -07:00
Jaegeuk Kim
554df79e52 f2fs: shrink extent_cache entries
This patch registers shrinking extent_caches.

Reviewed-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-08-04 14:09:55 -07:00
Jaegeuk Kim
1b38dc8e74 f2fs: shrink nat_cache entries
This patch registers shrinking nat_cache entries.

Reviewed-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-08-04 14:09:55 -07:00
Jaegeuk Kim
2658e50de6 f2fs: introduce a shrinker for mounted fs
This patch introduces a shrinker targeting to reduce memory footprint consumed
by a number of in-memory f2fs data structures.

In addition, it newly adds:
 - sbi->umount_mutex to avoid data races on shrinker and put_super
 - sbi->shruinker_run_no to not revisit objects

Note that the basic implementation was copied from fs/ubifs/shrinker.c

Reviewed-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-08-04 14:09:54 -07:00
Jaegeuk Kim
244f4fc1c5 f2fs: set cached_en after checking finally
This patch relocates cached_en not only to be covered by spin_lock, but also
to set once after checking out completely.

Reviewed-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-08-04 14:09:54 -07:00
Jaegeuk Kim
cbe91923a9 f2fs: update on-disk extents even under extent_cache
Previously, f2fs_update_extent_cache() updates in-memory extent_cache all the
time, and then finally preserves its up-to-date extent into on-disk one during
f2fs_evict_inode.

But, in the following scenario:

1. mount
2. open & write an extent X
3. f2fs_evict_inode; on-disk extent is X
4. open & update the extent X with Y
5. sync; trigger checkpoint
6. power-cut

after power-on, f2fs should serve extent Y, but we have an on-disk extent X.

This causes a failure on xfstests/311.

Reviewed-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-08-04 14:09:54 -07:00
Jaegeuk Kim
7a2cb67867 f2fs: fix wrong block address calculation for a split extent
This patch fixes wrong calculation on block address field when an extent is
split.

Reviewed-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-08-04 14:09:54 -07:00
Jaegeuk Kim
97a7b2c274 f2fs: convert inline_data for various fallocate
For newly added fallocate types, it should convert inline_data before handling
block swapping.

Reviewed-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-08-04 14:09:53 -07:00
Jaegeuk Kim
c9b63bd01d f2fs: avoid to use failed inode immediately
Before iput is called, the inode number used by a bad inode can be reassigned
to other new inode, resulting in any abnormal behaviors on the new inode.
This should not happen for the new inode.

Reviewed-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-08-04 14:09:53 -07:00
Jaegeuk Kim
eca616f8c1 f2fs: avoid freed stat information
The write_checkpoint can update stat information, so we should destroy the stat
structure after it.

Reviewed-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-08-04 14:09:53 -07:00
Chao Yu
5ac9f36fca f2fs: fix to record dirty page count for symlink
Dirty page can be exist in mapping of newly created symlink, but previously
we did not maintain the counting of dirty page for symlink like we maintained
for regular/directory, so the counting we lookuped should be wrong.

This patch adds missed dirty page counting for symlink to fix this issue.

Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-08-04 14:09:52 -07:00
Markus Elfring
92859a5efd f2fs crypto: delete an unnecessary check before the function call "key_put"
The key_put() function tests whether its argument is NULL and then
returns immediately. Thus the test around the call is not needed.

This issue was detected by using the Coccinelle software.

Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-08-04 14:09:52 -07:00
Linus Torvalds
7e884479bf Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client
Pull Ceph fixes from Sage Weil:
 "There are two critical regression fixes for CephFS from Zheng, and an
  RBD completion fix for layered images from Ilya"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client:
  rbd: fix copyup completion race
  ceph: always re-send cap flushes when MDS recovers
  ceph: fix ceph_encode_locks_to_buffer()
2015-08-03 11:09:07 -07:00
Linus Torvalds
01183609ab Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull VFS fix from Al Viro:
 "Spurious ENOTDIR fix"

This should fix the problems reported by Dominique Martinet and Hugh
Dickins.

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  link_path_walk(): be careful when failing with ENOTDIR
2015-08-01 17:42:14 -07:00
Al Viro
97242f99a0 link_path_walk(): be careful when failing with ENOTDIR
In RCU mode we might end up with dentry evicted just we check
that it's a directory.  In such case we should return ECHILD
rather than ENOTDIR, so that pathwalk would be retries in non-RCU
mode.

Breakage had been introduced in commit b18825a - prior to that
we were looking at nd->inode, which had been fetched before
verifying that ->d_seq was still valid.  That form of check
would only be satisfied if at some point the pathname prefix
would indeed have resolved to a non-directory.  The fix consists
of checking ->d_seq after we'd run into a non-directory dentry,
and failing with ECHILD in case of mismatch.

Note that all branches since 3.12 have that problem...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-08-01 20:18:38 -04:00
Linus Torvalds
acea568fa9 Merge branch 'for-linus-4.2' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs
Pull btrfs fixes from Chris Mason:
 "Filipe fixed up a hard to trigger ENOSPC regression from our merge
  window pull, and we have a few other smaller fixes"

* 'for-linus-4.2' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs:
  Btrfs: fix quick exhaustion of the system array in the superblock
  btrfs: its btrfs_err() instead of btrfs_error()
  btrfs: Avoid NULL pointer dereference of free_extent_buffer when read_tree_block() fail
  btrfs: Fix lockdep warning of btrfs_run_delayed_iputs()
2015-07-31 17:05:37 -07:00
Yan, Zheng
fc927cd32f ceph: always re-send cap flushes when MDS recovers
commit e548e9b93d makes the kclient
only re-send cap flush once during MDS failover. If the kclient sends
a cap flush after MDS enters reconnect stage but before MDS recovers.
The kclient will skip re-sending the same cap flush when MDS recovers.

This causes problem for newly created inode. The MDS handles cap
flushes before replaying unsafe requests, so it's possible that MDS
find corresponding inode is missing when handling cap flush. The fix
is reverting to old behaviour: always re-send when MDS recovers

Signed-off-by: Yan, Zheng <zyan@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2015-07-31 11:38:53 +03:00
Yan, Zheng
f6762cb2ca ceph: fix ceph_encode_locks_to_buffer()
posix locks should be in ctx->flc_posix list

Signed-off-by: Yan, Zheng <zyan@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2015-07-31 11:38:47 +03:00
Linus Torvalds
8400935737 xfs: updates for 4.2-rc4
- remote attribute log recovery corruption fixes
 - DAX page faults need to use direct mappings, not a page cache
   mapping.
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Merge tag 'xfs-for-linus-4.2-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/dgc/linux-xfs

Pull xfs fixes from Dave Chinner:
 "There are a couple of recently found, long standing remote attribute
  corruption fixes caused by log recovery getting confused after a
  crash, and the new DAX code in XFS (merged in 4.2-rc1) needs to
  actually use the DAX fault path on read faults.

  Summary:

   - remote attribute log recovery corruption fixes

   - DAX page faults need to use direct mappings, not a page cache
     mapping"

* tag 'xfs-for-linus-4.2-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/dgc/linux-xfs:
  xfs: remote attributes need to be considered data
  xfs: remote attribute headers contain an invalid LSN
  xfs: call dax_fault on read page faults for DAX
2015-07-30 20:36:49 -07:00
Dave Chinner
df150ed102 xfs: remote attributes need to be considered data
We don't log remote attribute contents, and instead write them
synchronously before we commit the block allocation and attribute
tree update transaction. As a result we are writing to the allocated
space before the allcoation has been made permanent.

As a result, we cannot consider this allocation to be a metadata
allocation. Metadata allocation can take blocks from the free list
and so reuse them before the transaction that freed the block is
committed to disk. This behaviour is perfectly fine for journalled
metadata changes as log recovery will ensure the free operation is
replayed before the overwrite, but for remote attribute writes this
is not the case.

Hence we have to consider the remote attribute blocks to contain
data and allocate accordingly. We do this by dropping the
XFS_BMAPI_METADATA flag from the block allocation. This means the
allocation will not use blocks that are on the busy list without
first ensuring that the freeing transaction has been committed to
disk and the blocks removed from the busy list. This ensures we will
never overwrite a freed block without first ensuring that it is
really free.

cc: <stable@vger.kernel.org>
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2015-07-29 11:48:02 +10:00
Dave Chinner
e3c32ee9e3 xfs: remote attribute headers contain an invalid LSN
In recent testing, a system that crashed failed log recovery on
restart with a bad symlink buffer magic number:

XFS (vda): Starting recovery (logdev: internal)
XFS (vda): Bad symlink block magic!
XFS: Assertion failed: 0, file: fs/xfs/xfs_log_recover.c, line: 2060

On examination of the log via xfs_logprint, none of the symlink
buffers in the log had a bad magic number, nor were any other types
of buffer log format headers mis-identified as symlink buffers.
Tracing was used to find the buffer the kernel was tripping over,
and xfs_db identified it's contents as:

000: 5841524d 00000000 00000346 64d82b48 8983e692 d71e4680 a5f49e2c b317576e
020: 00000000 00602038 00000000 006034ce d0020000 00000000 4d4d4d4d 4d4d4d4d
040: 4d4d4d4d 4d4d4d4d 4d4d4d4d 4d4d4d4d 4d4d4d4d 4d4d4d4d 4d4d4d4d 4d4d4d4d
060: 4d4d4d4d 4d4d4d4d 4d4d4d4d 4d4d4d4d 4d4d4d4d 4d4d4d4d 4d4d4d4d 4d4d4d4d
.....

This is a remote attribute buffer, which are notable in that they
are not logged but are instead written synchronously by the remote
attribute code so that they exist on disk before the attribute
transactions are committed to the journal.

The above remote attribute block has an invalid LSN in it - cycle
0xd002000, block 0 - which means when log recovery comes along to
determine if the transaction that writes to the underlying block
should be replayed, it sees a block that has a future LSN and so
does not replay the buffer data in the transaction. Instead, it
validates the buffer magic number and attaches the buffer verifier
to it.  It is this buffer magic number check that is failing in the
above assert, indicating that we skipped replay due to the LSN of
the underlying buffer.

The problem here is that the remote attribute buffers cannot have a
valid LSN placed into them, because the transaction that contains 
the attribute tree pointer changes and the block allocation that the
attribute data is being written to hasn't yet been committed. Hence
the LSN field in the attribute block is completely unwritten,
thereby leaving the underlying contents of the block in the LSN
field. It could have any value, and hence a future overwrite of the
block by log recovery may or may not work correctly.

Fix this by always writing an invalid LSN to the remote attribute
block, as any buffer in log recovery that needs to write over the
remote attribute should occur. We are protected from having old data
written over the attribute by the fact that freeing the block before
the remote attribute is written will result in the buffer being
marked stale in the log and so all changes prior to the buffer stale
transaction will be cancelled by log recovery.

Hence it is safe to ignore the LSN in the case or synchronously
written, unlogged metadata such as remote attribute blocks, and to
ensure we do that correctly, we need to write an invalid LSN to all
remote attribute blocks to trigger immediate recovery of metadata
that is written over the top.

As a further protection for filesystems that may already have remote
attribute blocks with bad LSNs on disk, change the log recovery code
to always trigger immediate recovery of metadata over remote
attribute blocks.

cc: <stable@vger.kernel.org>
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2015-07-29 11:48:01 +10:00
Dave Chinner
b2442c5a7f xfs: call dax_fault on read page faults for DAX
When modifying the patch series to handle the XFS MMAP_LOCK nesting
of page faults, I botched the conversion of the read page fault
path, and so it is only every calling through the page cache. Re-add
the necessary __dax_fault() call for such files.

Because the get_blocks callback on read faults may not set up the
mapping buffer correctly to allow unwritten extent completion to be
run, we need to allow callers of __dax_fault() to pass a null
complete_unwritten() callback. The DAX code always zeros the
unwritten page when it is read faulted so there are no stale data
exposure issues with not doing the conversion. The only downside
will be the potential for increased CPU overhead on repeated read
faults of the same page. If this proves to be a problem, then the
filesystem needs to fix it's get_block callback and provide a
convert_unwritten() callback to the read fault path.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Matthew Wilcox <willy@linux.intel.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2015-07-29 11:48:00 +10:00
Linus Torvalds
d8132e08d2 NFS client bugfixes for Linux 4.2
Highlights include:
 
 Stable patches:
 - Fix a situation where the client uses the wrong (zero) stateid.
 - Fix a memory leak in nfs_do_recoalesce
 
 Bugfixes:
 - Plug a memory leak when ->prepare_layoutcommit fails
 - Fix an Oops in the NFSv4 open code
 - Fix a backchannel deadlock
 - Fix a livelock in sunrpc when sendmsg fails due to low memory availability
 - Don't revalidate the mapping if both size and change attr are up to date
 - Ensure we don't miss a file extension when doing pNFS
 - Several fixes to handle NFSv4.1 sequence operation status bits correctly
 - Several pNFS layout return bugfixes
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Merge tag 'nfs-for-4.2-2' of git://git.linux-nfs.org/projects/trondmy/linux-nfs

Pull NFS client bugfixes from Trond Myklebust:
 "Highlights include:

  Stable patches:
   - Fix a situation where the client uses the wrong (zero) stateid.
   - Fix a memory leak in nfs_do_recoalesce

  Bugfixes:
   - Plug a memory leak when ->prepare_layoutcommit fails
   - Fix an Oops in the NFSv4 open code
   - Fix a backchannel deadlock
   - Fix a livelock in sunrpc when sendmsg fails due to low memory
     availability
   - Don't revalidate the mapping if both size and change attr are up to
     date
   - Ensure we don't miss a file extension when doing pNFS
   - Several fixes to handle NFSv4.1 sequence operation status bits
     correctly
   - Several pNFS layout return bugfixes"

* tag 'nfs-for-4.2-2' of git://git.linux-nfs.org/projects/trondmy/linux-nfs: (28 commits)
  nfs: Fix an oops caused by using other thread's stack space in ASYNC mode
  nfs: plug memory leak when ->prepare_layoutcommit fails
  SUNRPC: Report TCP errors to the caller
  sunrpc: translate -EAGAIN to -ENOBUFS when socket is writable.
  NFSv4.2: handle NFS-specific llseek errors
  NFS: Don't clear desc->pg_moreio in nfs_do_recoalesce()
  NFS: Fix a memory leak in nfs_do_recoalesce
  NFS: nfs_mark_for_revalidate should always set NFS_INO_REVAL_PAGECACHE
  NFS: Remove the "NFS_CAP_CHANGE_ATTR" capability
  NFS: Set NFS_INO_REVAL_PAGECACHE if the change attribute is uninitialised
  NFS: Don't revalidate the mapping if both size and change attr are up to date
  NFSv4/pnfs: Ensure we don't miss a file extension
  NFSv4: We must set NFS_OPEN_STATE flag in nfs_resync_open_stateid_locked
  SUNRPC: xprt_complete_bc_request must also decrement the free slot count
  SUNRPC: Fix a backchannel deadlock
  pNFS: Don't throw out valid layout segments
  pNFS: pnfs_roc_drain() fix a race with open
  pNFS: Fix races between return-on-close and layoutreturn.
  pNFS: pnfs_roc_drain should return 'true' when sleeping
  pNFS: Layoutreturn must invalidate all existing layout segments.
  ...
2015-07-28 09:37:44 -07:00
Kinglong Mee
a49c269111 nfs: Fix an oops caused by using other thread's stack space in ASYNC mode
An oops caused by using other thread's stack space in sunrpc ASYNC sending thread.

[ 9839.007187] ------------[ cut here ]------------
[ 9839.007923] kernel BUG at fs/nfs/nfs4xdr.c:910!
[ 9839.008069] invalid opcode: 0000 [#1] SMP
[ 9839.008069] Modules linked in: blocklayoutdriver rpcsec_gss_krb5 nfsv4 dns_resolver nfs fscache snd_hda_codec_generic snd_hda_intel snd_hda_controller snd_hda_codec snd_hwdep snd_seq snd_seq_device snd_pcm joydev iosf_mbi crct10dif_pclmul snd_timer crc32_pclmul crc32c_intel ghash_clmulni_intel snd soundcore ppdev pvpanic parport_pc i2c_piix4 serio_raw virtio_balloon parport acpi_cpufreq nfsd nfs_acl lockd grace auth_rpcgss sunrpc qxl drm_kms_helper virtio_net virtio_console virtio_blk ttm drm virtio_pci virtio_ring virtio ata_generic pata_acpi
[ 9839.008069] CPU: 0 PID: 308 Comm: kworker/0:1H Not tainted 4.0.0-0.rc4.git1.3.fc23.x86_64 #1
[ 9839.008069] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
[ 9839.008069] Workqueue: rpciod rpc_async_schedule [sunrpc]
[ 9839.008069] task: ffff8800d8b4d8e0 ti: ffff880036678000 task.ti: ffff880036678000
[ 9839.008069] RIP: 0010:[<ffffffffa0339cc9>]  [<ffffffffa0339cc9>] reserve_space.part.73+0x9/0x10 [nfsv4]
[ 9839.008069] RSP: 0018:ffff88003667ba58  EFLAGS: 00010246
[ 9839.008069] RAX: 0000000000000000 RBX: 000000001fc15e18 RCX: ffff8800c0193800
[ 9839.008069] RDX: ffff8800e4ae3f24 RSI: 000000001fc15e2c RDI: ffff88003667bcd0
[ 9839.008069] RBP: ffff88003667ba58 R08: ffff8800d9173008 R09: 0000000000000003
[ 9839.008069] R10: ffff88003667bcd0 R11: 000000000000000c R12: 0000000000010000
[ 9839.008069] R13: ffff8800d9173350 R14: 0000000000000000 R15: ffff8800c0067b98
[ 9839.008069] FS:  0000000000000000(0000) GS:ffff88011fc00000(0000) knlGS:0000000000000000
[ 9839.008069] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 9839.008069] CR2: 00007f988c9c8bb0 CR3: 00000000d99b6000 CR4: 00000000000407f0
[ 9839.008069] Stack:
[ 9839.008069]  ffff88003667bbc8 ffffffffa03412c5 00000000c6c55680 ffff880000000003
[ 9839.008069]  0000000000000088 00000010c6c55680 0001000000000002 ffffffff816e87e9
[ 9839.008069]  0000000000000000 00000000477290e2 ffff88003667bab8 ffffffff81327ba3
[ 9839.008069] Call Trace:
[ 9839.008069]  [<ffffffffa03412c5>] encode_attrs+0x435/0x530 [nfsv4]
[ 9839.008069]  [<ffffffff816e87e9>] ? inet_sendmsg+0x69/0xb0
[ 9839.008069]  [<ffffffff81327ba3>] ? selinux_socket_sendmsg+0x23/0x30
[ 9839.008069]  [<ffffffff8164c1df>] ? do_sock_sendmsg+0x9f/0xc0
[ 9839.008069]  [<ffffffff8164c278>] ? kernel_sendmsg+0x58/0x70
[ 9839.008069]  [<ffffffffa011acc0>] ? xdr_reserve_space+0x20/0x170 [sunrpc]
[ 9839.008069]  [<ffffffffa011acc0>] ? xdr_reserve_space+0x20/0x170 [sunrpc]
[ 9839.008069]  [<ffffffffa0341b40>] ? nfs4_xdr_enc_open_noattr+0x130/0x130 [nfsv4]
[ 9839.008069]  [<ffffffffa03419a5>] encode_open+0x2d5/0x340 [nfsv4]
[ 9839.008069]  [<ffffffffa0341b40>] ? nfs4_xdr_enc_open_noattr+0x130/0x130 [nfsv4]
[ 9839.008069]  [<ffffffffa011ab89>] ? xdr_encode_opaque+0x19/0x20 [sunrpc]
[ 9839.008069]  [<ffffffffa0339cfb>] ? encode_string+0x2b/0x40 [nfsv4]
[ 9839.008069]  [<ffffffffa0341bf3>] nfs4_xdr_enc_open+0xb3/0x140 [nfsv4]
[ 9839.008069]  [<ffffffffa0110a4c>] rpcauth_wrap_req+0xac/0xf0 [sunrpc]
[ 9839.008069]  [<ffffffffa01017db>] call_transmit+0x18b/0x2d0 [sunrpc]
[ 9839.008069]  [<ffffffffa0101650>] ? call_decode+0x860/0x860 [sunrpc]
[ 9839.008069]  [<ffffffffa0101650>] ? call_decode+0x860/0x860 [sunrpc]
[ 9839.008069]  [<ffffffffa010caa0>] __rpc_execute+0x90/0x460 [sunrpc]
[ 9839.008069]  [<ffffffffa010ce85>] rpc_async_schedule+0x15/0x20 [sunrpc]
[ 9839.008069]  [<ffffffff810b452b>] process_one_work+0x1bb/0x410
[ 9839.008069]  [<ffffffff810b47d3>] worker_thread+0x53/0x470
[ 9839.008069]  [<ffffffff810b4780>] ? process_one_work+0x410/0x410
[ 9839.008069]  [<ffffffff810b4780>] ? process_one_work+0x410/0x410
[ 9839.008069]  [<ffffffff810ba7b8>] kthread+0xd8/0xf0
[ 9839.008069]  [<ffffffff810ba6e0>] ? kthread_worker_fn+0x180/0x180
[ 9839.008069]  [<ffffffff81786418>] ret_from_fork+0x58/0x90
[ 9839.008069]  [<ffffffff810ba6e0>] ? kthread_worker_fn+0x180/0x180
[ 9839.008069] Code: 00 00 48 c7 c7 21 fa 37 a0 e8 94 1c d6 e0 c6 05 d2 17 05 00 01 8b 03 eb d7 66 0f 1f 84 00 00 00 00 00 66 66 66 66 90 55 48 89 e5 <0f> 0b 0f 1f 44 00 00 66 66 66 66 90 55 48 89 e5 41 54 53 89 f3
[ 9839.008069] RIP  [<ffffffffa0339cc9>] reserve_space.part.73+0x9/0x10 [nfsv4]
[ 9839.008069]  RSP <ffff88003667ba58>
[ 9839.071114] ---[ end trace cc14c03adb522e94 ]---

Signed-off-by: Kinglong Mee <kinglongmee@gmail.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-07-28 09:07:03 -04:00
Jeff Layton
3471648a75 nfs: plug memory leak when ->prepare_layoutcommit fails
"data" is currently leaked when the prepare_layoutcommit operation
returns an error. Put the cred before taking the spinlock in that
case, take the lock and then goto out_unlock which will drop the
lock and then free "data".

Signed-off-by: Jeff Layton <jeff.layton@primarydata.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-07-28 09:07:02 -04:00
J. Bruce Fields
bdcc2cd14e NFSv4.2: handle NFS-specific llseek errors
Handle NFS-specific llseek errors instead of letting them leak out to
userspace.

Reported-by: Benjamin Coddington <bcodding@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-07-27 11:16:25 -04:00
Trond Myklebust
d4c30454db NFS: Don't clear desc->pg_moreio in nfs_do_recoalesce()
Recoalescing does not affect whether or not we've already sent off
I/O, and doing so means that we end up sending a bunch of synchronous
for cases where we actually need to be using unstable writes.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-07-27 10:33:12 -04:00
Trond Myklebust
03d5eb65b5 NFS: Fix a memory leak in nfs_do_recoalesce
If the function exits early, then we must put those requests that were
not processed back onto the &mirror->pg_list so they can be cleaned up
by nfs_pgio_error().

Fixes: a7d42ddb30 ("nfs: add mirroring support to pgio layer")
Cc: stable@vger.kernel.org # v4.0+
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-07-27 10:33:08 -04:00
Jaegeuk Kim
6282adbf93 f2fs: call set_page_dirty to attach i_wb for cgroup
The cgroup attaches inode->i_wb via mark_inode_dirty and when set_page_writeback
is called, __inc_wb_stat() updates i_wb's stat.

So, we need to explicitly call set_page_dirty->__mark_inode_dirty in prior to
any writebacking pages.

This patch should resolve the following kernel panic reported by Andreas Reis.

https://bugzilla.kernel.org/show_bug.cgi?id=101801

--- Comment #2 from Andreas Reis <andreas.reis@gmail.com> ---
BUG: unable to handle kernel NULL pointer dereference at 00000000000000a8
IP: [<ffffffff8149deea>] __percpu_counter_add+0x1a/0x90
PGD 2951ff067 PUD 2df43f067 PMD 0
Oops: 0000 [#1] PREEMPT SMP
Modules linked in:
CPU: 7 PID: 10356 Comm: gcc Tainted: G        W       4.2.0-1-cu #1
Hardware name: Gigabyte Technology Co., Ltd. G1.Sniper M5/G1.Sniper M5, BIOS
T01 02/03/2015
task: ffff880295044f80 ti: ffff880295140000 task.ti: ffff880295140000
RIP: 0010:[<ffffffff8149deea>]  [<ffffffff8149deea>]
__percpu_counter_add+0x1a/0x90
RSP: 0018:ffff880295143ac8  EFLAGS: 00010082
RAX: 0000000000000003 RBX: ffffea000a526d40 RCX: 0000000000000001
RDX: 0000000000000020 RSI: 0000000000000001 RDI: 0000000000000088
RBP: ffff880295143ae8 R08: 0000000000000000 R09: ffff88008f69bb30
R10: 00000000fffffffa R11: 0000000000000000 R12: 0000000000000088
R13: 0000000000000001 R14: ffff88041d099000 R15: ffff880084a205d0
FS:  00007f8549374700(0000) GS:ffff88042f3c0000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00000000000000a8 CR3: 000000033e1d5000 CR4: 00000000001406e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Stack:
 0000000000000000 ffffea000a526d40 ffff880084a20738 ffff880084a20750
 ffff880295143b48 ffffffff811cc91e ffff880000000000 0000000000000296
 0000000000000000 ffff880417090198 0000000000000000 ffffea000a526d40
Call Trace:
 [<ffffffff811cc91e>] __test_set_page_writeback+0xde/0x1d0
 [<ffffffff813fee87>] do_write_data_page+0xe7/0x3a0
 [<ffffffff813faeea>] gc_data_segment+0x5aa/0x640
 [<ffffffff813fb0b8>] do_garbage_collect+0x138/0x150
 [<ffffffff813fb3fe>] f2fs_gc+0x1be/0x3e0
 [<ffffffff81405541>] f2fs_balance_fs+0x81/0x90
 [<ffffffff813ee357>] f2fs_unlink+0x47/0x1d0
 [<ffffffff81239329>] vfs_unlink+0x109/0x1b0
 [<ffffffff8123e3d7>] do_unlinkat+0x287/0x2c0
 [<ffffffff8123ebc6>] SyS_unlink+0x16/0x20
 [<ffffffff81942e2e>] entry_SYSCALL_64_fastpath+0x12/0x71
Code: 41 5e 5d c3 0f 1f 00 66 2e 0f 1f 84 00 00 00 00 00 55 48 89 e5 41 55 49
89 f5 41 54 49 89 fc 53 48 83 ec 08 65 ff 05 e6 d9 b6 7e <48> 8b 47 20 48 63 ca
65 8b 18 48 63 db 48 01 f3 48 39 cb 7d 0a
RIP  [<ffffffff8149deea>] __percpu_counter_add+0x1a/0x90
 RSP <ffff880295143ac8>
CR2: 00000000000000a8
---[ end trace 5132449a58ed93a3 ]---
note: gcc[10356] exited with preempt_count 2

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-07-25 08:54:26 -07:00
Jaegeuk Kim
548aedac51 f2fs: handle error cases in move_encrypted_block
This patch fixes some missing error handlers.

Reviewed-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-07-25 08:54:25 -07:00
Linus Torvalds
33b40178cb Merge branch 'for-linus' of git://git.kernel.dk/linux-block
Pull block fixes from Jens Axboe:
 "Four smaller fixes for the current series.  This contains:

   - A fix for clones of discard bio's, that can cause data corruption.
     From Martin.

   - A fix for null_blk, where in certain queue modes it could access a
     request after it had been freed.  From Mike Krinkin.

   - An error handling leak fix for blkcg, from Tejun.

   - Also from Tejun, export of the functions that a file system needs
     to implement cgroup writeback support"

* 'for-linus' of git://git.kernel.dk/linux-block:
  block: Do a full clone when splitting discard bios
  block: export bio_associate_*() and wbc_account_io()
  blkcg: fix gendisk reference leak in blkg_conf_prep()
  null_blk: fix use-after-free problem
2015-07-24 17:00:04 -07:00
Linus Torvalds
45b4b782e8 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace
Pull namespace fixes from Eric Biederman:
 "While reading through the code of detach_mounts I realized the code
  was slightly off.  Testing it revealed two buggy corner cases that can
  send the code of detach_mounts into an infinite loop.

  Fixing the code to do the right thing removes the possibility of these
  user triggered infinite loops in the code"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace:
  mnt: In detach_mounts detach the appropriate unmounted mount
  mnt: Clarify and correct the disconnect logic in umount_tree
2015-07-23 13:16:21 -07:00
Tejun Heo
5aa2a96b34 block: export bio_associate_*() and wbc_account_io()
bio_associate_blkcg(), bio_associate_current() and wbc_account_io()
are used to implement cgroup writeback support for filesystems and
thus need to be exported.  Export them.

Signed-off-by: Tejun Heo <tj@kernel.org>
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Jens Axboe <axboe@fb.com>
2015-07-23 13:36:44 -06:00
Eric W. Biederman
fe78fcc85a mnt: In detach_mounts detach the appropriate unmounted mount
The handling of in detach_mounts of unmounted but connected mounts is
buggy and can lead to an infinite loop.

Correct the handling of unmounted mounts in detach_mount.  When the
mountpoint of an unmounted but connected mount is connected to a
dentry, and that dentry is deleted we need to disconnect that mount
from the parent mount and the deleted dentry.

Nothing changes for the unmounted and connected children.  They can be
safely ignored.

Cc: stable@vger.kernel.org
Fixes: ce07d891a0 mnt: Honor MNT_LOCKED when detaching mounts
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2015-07-23 11:31:15 -05:00
Eric W. Biederman
f2d0a123bc mnt: Clarify and correct the disconnect logic in umount_tree
rmdir mntpoint will result in an infinite loop when there is
a mount locked on the mountpoint in another mount namespace.

This is because the logic to test to see if a mount should
be disconnected in umount_tree is buggy.

Move the logic to decide if a mount should remain connected to
it's mountpoint into it's own function disconnect_mount so that
clarity of expression instead of terseness of expression becomes
a virtue.

When the conditions where it is invalid to leave a mount connected
are first ruled out, the logic for deciding if a mount should
be disconnected becomes much clearer and simpler.

Fixes: e0c9c0afd2 mnt: Update detach_mounts to leave mounts connected
Fixes: ce07d891a0 mnt: Honor MNT_LOCKED when detaching mounts
Cc: stable@vger.kernel.org
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2015-07-22 20:33:27 -05:00