Commit Graph

2271 Commits

Author SHA1 Message Date
Dmitry Monakhov
4b1f166071 ext4: add i_data_sem sanity check
Each caller of ext4_ext_dirty must hold i_data_sem,
The only exception is migration code, let's make it convenient.

Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Jan Kara <jack@suse.cz>
2014-07-27 22:28:15 -04:00
Xiaoguang Wang
b27b1535ac ext4: fix wrong size computation in ext4_mb_normalize_request()
As the member fe_len defined in struct ext4_free_extent is expressed as
number of clusters, the variable "size" computation is wrong, we need to
first translate fe_len to block number, then to bytes.

Signed-off-by: Xiaoguang Wang <wangxg.fnst@cn.fujitsu.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Lukas Czerner <lczerner@redhat.com>
2014-07-27 22:26:36 -04:00
Zheng Liu
83447ccb4d ext4: make ext4_has_inline_data() as a inline function
Now ext4_has_inline_data() is used in wide spread codepaths.  So we need
to make it as a inline function to avoid burning some CPU cycles.

Change in text size:

         text     data      bss     dec     hex filename
before: 326110    19258    5528  350896   55ab0 fs/ext4/ext4.o
after:  326227    19258    5528  351013   55b25 fs/ext4/ext4.o

I use the following script to measure the CPU usage.

  #!/bin/bash

  shm_base='/dev/shm'
  img=${shm_base}/ext4-img
  mnt=/mnt/loop

  e2fsprgs_base=$HOME/e2fsprogs
  mkfs=${e2fsprgs_base}/misc/mke2fs
  fsck=${e2fsprgs_base}/e2fsck/e2fsck

  sudo umount $mnt
  dd if=/dev/zero of=$img bs=4k count=3145728
  ${mkfs} -t ext4 -O inline_data -F $img
  sudo mount -t ext4 -o loop $img $mnt

  # start testing...
  testdir="${mnt}/testdir"
  mkdir $testdir
  cd $testdir

  echo "start testing..."
  for ((cnt=0;cnt<100;cnt++)); do

  for ((i=0;i<5;i++)); do
  	for ((j=0;j<5;j++)); do
  		for ((k=0;k<5;k++)); do
  			for ((l=0;l<5;l++)); do
  				mkdir -p $i/$j/$k/$l
  				echo "$i-$j-$k-$l" > $i/$j/$k/$l/testfile
  			done
  		done
  	done
  done

  ls -R $testdir > /dev/null
  rm -rf $testdir/*

  done

The result of `perf top -G -U` is as below.

vanilla:
 13.92%  [ext4]  [k] ext4_do_update_inode
  9.36%  [ext4]  [k] __ext4_get_inode_loc
  4.07%  [ext4]  [k] ftrace_define_fields_ext4_writepages
  3.83%  [ext4]  [k] __ext4_handle_dirty_metadata
  3.42%  [ext4]  [k] ext4_get_inode_flags
  2.71%  [ext4]  [k] ext4_mark_iloc_dirty
  2.46%  [ext4]  [k] ftrace_define_fields_ext4_direct_IO_enter
  2.26%  [ext4]  [k] ext4_get_inode_loc
  2.22%  [ext4]  [k] ext4_has_inline_data
  [...]

After applied the patch, we don't see ext4_has_inline_data() because it
has been inlined and perf couldn't sample it.  Although it doesn't mean
that the CPU cycles can be saved but at least the overhead of function
calls can be eliminated.  So IMHO we'd better inline this function.

Cc: Andreas Dilger <adilger.kernel@dilger.ca>
Signed-off-by: Zheng Liu <wenqing.lz@taobao.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2014-07-15 10:10:04 -04:00
Zhang Zhen
590a141863 ext4: remove readpage() check in ext4_mmap_file()
There is no kind of file which does not supply a page reading function.

Signed-off-by: Zhang Zhen <zhenzhang.zhang@huawei.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2014-07-15 09:56:19 -04:00
Lukas Czerner
4f579ae7de ext4: fix punch hole on files with indirect mapping
Currently punch hole code on files with direct/indirect mapping has some
problems which may lead to a data loss. For example (from Jan Kara):

fallocate -n -p 10240000 4096

will punch the range 10240000 - 12632064 instead of the range 1024000 -
10244096.

Also the code is a bit weird and it's not using infrastructure provided
by indirect.c, but rather creating it's own way.

This patch fixes the issues as well as making the operation to run 4
times faster from my testing (punching out 60GB file). It uses similar
approach used in ext4_ind_truncate() which takes advantage of
ext4_free_branches() function.

Also rename the ext4_free_hole_blocks() to something more sensible, like
the equivalent we have for extent mapped files. Call it
ext4_ind_remove_space().

This has been tested mostly with fsx and some xfstests which are testing
punch hole but does not require unwritten extents which are not
supported with direct/indirect mapping. Not problems showed up even with
1024k block size.

CC: stable@vger.kernel.org
Signed-off-by: Lukas Czerner <lczerner@redhat.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2014-07-15 06:03:38 -04:00
Theodore Ts'o
71d4f7d032 ext4: remove metadata reservation checks
Commit 27dd438542 ("ext4: introduce reserved space") reserves 2% of
the file system space to make sure metadata allocations will always
succeed.  Given that, tracking the reservation of metadata blocks is
no longer necessary.

Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2014-07-15 06:02:38 -04:00
Theodore Ts'o
d5e03cbb0c ext4: rearrange initialization to fix EXT4FS_DEBUG
The EXT4FS_DEBUG is a *very* developer specific #ifdef designed for
ext4 developers only.  (You have to modify fs/ext4/ext4.h to enable
it.)

Rearrange how we initialize data structures to avoid calling
ext4_count_free_clusters() until the multiblock allocator has been
initialized.

This also allows us to only call ext4_count_free_clusters() once, and
simplifies the code somewhat.

(Thanks to Chen Gang <gang.chen.5i5j@gmail.com> for pointing out a
!CONFIG_SMP compile breakage in the original patch.)

Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Lukas Czerner <lczerner@redhat.com>
2014-07-15 06:01:38 -04:00
Namjae Jeon
bf40c92635 ext4: fix potential null pointer dereference in ext4_free_inode
Fix potential null pointer dereferencing problem caused by e43bb4e612
("ext4: decrement free clusters/inodes counters when block group declared bad")

Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Namjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: Ashish Sangwan <a.sangwan@samsung.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Lukas Czerner <lczerner@redhat.com>
2014-07-12 16:11:42 -04:00
Theodore Ts'o
3f1f9b8513 ext4: fix a potential deadlock in __ext4_es_shrink()
This fixes the following lockdep complaint:

[ INFO: possible circular locking dependency detected ]
3.16.0-rc2-mm1+ #7 Tainted: G           O  
-------------------------------------------------------
kworker/u24:0/4356 is trying to acquire lock:
 (&(&sbi->s_es_lru_lock)->rlock){+.+.-.}, at: [<ffffffff81285fff>] __ext4_es_shrink+0x4f/0x2e0

but task is already holding lock:
 (&ei->i_es_lock){++++-.}, at: [<ffffffff81286961>] ext4_es_insert_extent+0x71/0x180

which lock already depends on the new lock.

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(&ei->i_es_lock);
                               lock(&(&sbi->s_es_lru_lock)->rlock);
                               lock(&ei->i_es_lock);
  lock(&(&sbi->s_es_lru_lock)->rlock);

 *** DEADLOCK ***

6 locks held by kworker/u24:0/4356:
 #0:  ("writeback"){.+.+.+}, at: [<ffffffff81071d00>] process_one_work+0x180/0x560
 #1:  ((&(&wb->dwork)->work)){+.+.+.}, at: [<ffffffff81071d00>] process_one_work+0x180/0x560
 #2:  (&type->s_umount_key#22){++++++}, at: [<ffffffff811a9c74>] grab_super_passive+0x44/0x90
 #3:  (jbd2_handle){+.+...}, at: [<ffffffff812979f9>] start_this_handle+0x189/0x5f0
 #4:  (&ei->i_data_sem){++++..}, at: [<ffffffff81247062>] ext4_map_blocks+0x132/0x550
 #5:  (&ei->i_es_lock){++++-.}, at: [<ffffffff81286961>] ext4_es_insert_extent+0x71/0x180

stack backtrace:
CPU: 0 PID: 4356 Comm: kworker/u24:0 Tainted: G           O   3.16.0-rc2-mm1+ #7
Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
Workqueue: writeback bdi_writeback_workfn (flush-253:0)
 ffffffff8213dce0 ffff880014b07538 ffffffff815df0bb 0000000000000007
 ffffffff8213e040 ffff880014b07588 ffffffff815db3dd ffff880014b07568
 ffff880014b07610 ffff88003b868930 ffff88003b868908 ffff88003b868930
Call Trace:
 [<ffffffff815df0bb>] dump_stack+0x4e/0x68
 [<ffffffff815db3dd>] print_circular_bug+0x1fb/0x20c
 [<ffffffff810a7a3e>] __lock_acquire+0x163e/0x1d00
 [<ffffffff815e89dc>] ? retint_restore_args+0xe/0xe
 [<ffffffff815ddc7b>] ? __slab_alloc+0x4a8/0x4ce
 [<ffffffff81285fff>] ? __ext4_es_shrink+0x4f/0x2e0
 [<ffffffff810a8707>] lock_acquire+0x87/0x120
 [<ffffffff81285fff>] ? __ext4_es_shrink+0x4f/0x2e0
 [<ffffffff8128592d>] ? ext4_es_free_extent+0x5d/0x70
 [<ffffffff815e6f09>] _raw_spin_lock+0x39/0x50
 [<ffffffff81285fff>] ? __ext4_es_shrink+0x4f/0x2e0
 [<ffffffff8119760b>] ? kmem_cache_alloc+0x18b/0x1a0
 [<ffffffff81285fff>] __ext4_es_shrink+0x4f/0x2e0
 [<ffffffff812869b8>] ext4_es_insert_extent+0xc8/0x180
 [<ffffffff812470f4>] ext4_map_blocks+0x1c4/0x550
 [<ffffffff8124c4c4>] ext4_writepages+0x6d4/0xd00
	...

Reported-by: Minchan Kim <minchan@kernel.org>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reported-by: Minchan Kim <minchan@kernel.org>
Cc: stable@vger.kernel.org
Cc: Zheng Liu <gnehzuil.liu@gmail.com>
2014-07-12 15:32:24 -04:00
Theodore Ts'o
f9ae9cf5d7 ext4: revert commit which was causing fs corruption after journal replays
Commit 007649375f ("ext4: initialize multi-block allocator before
checking block descriptors") causes the block group descriptor's count
of the number of free blocks to become inconsistent with the number of
free blocks in the allocation bitmap.  This is a harmless form of fs
corruption, but it causes the kernel to potentially remount the file
system read-only, or to panic, depending on the file systems's error
behavior.

Thanks to Eric Whitney for his tireless work to reproduce and to find
the guilty commit.

Fixes: 007649375f ("ext4: initialize multi-block allocator before checking block descriptors"

Cc: stable@vger.kernel.org  # 3.15
Reported-by: David Jander <david@protonic.nl>
Reported-by: Matteo Croce <technoboy85@gmail.com>
Tested-by: Eric Whitney <enwlinux@gmail.com>
Suggested-by: Eric Whitney <enwlinux@gmail.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2014-07-11 13:55:40 -04:00
Eric Sandeen
5dd214248f ext4: disable synchronous transaction batching if max_batch_time==0
The mount manpage says of the max_batch_time option,

	This optimization can be turned off entirely
	by setting max_batch_time to 0.

But the code doesn't do that.  So fix the code to do
that.

Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@vger.kernel.org
2014-07-05 19:18:22 -04:00
Theodore Ts'o
94d4c066a4 ext4: clarify ext4_error message in ext4_mb_generate_buddy_error()
We are spending a lot of time explaining to users what this error
means.  Let's try to improve the message to avoid this problem.

Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@vger.kernel.org
2014-07-05 19:15:50 -04:00
Theodore Ts'o
ae0f78de2c ext4: clarify error count warning messages
Make it clear that values printed are times, and that it is error
since last fsck. Also add note about fsck version required.

Signed-off-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Andreas Dilger <adilger@dilger.ca>
Cc: stable@vger.kernel.org
2014-07-05 18:40:52 -04:00
Theodore Ts'o
61c219f581 ext4: fix unjournalled bg descriptor while initializing inode bitmap
The first time that we allocate from an uninitialized inode allocation
bitmap, if the block allocation bitmap is also uninitalized, we need
to get write access to the block group descriptor before we start
modifying the block group descriptor flags and updating the free block
count, etc.  Otherwise, there is the potential of a bad journal
checksum (if journal checksums are enabled), and of the file system
becoming inconsistent if we crash at exactly the wrong time.

Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@vger.kernel.org
2014-07-05 16:28:35 -04:00
Jan Kara
a93cd4cf86 ext4: Fix hole punching for files with indirect blocks
Hole punching code for files with indirect blocks wrongly computed
number of blocks which need to be cleared when traversing the indirect
block tree. That could result in punching more blocks than actually
requested and thus effectively cause a data loss. For example:

fallocate -n -p 10240000 4096

will punch the range 10240000 - 12632064 instead of the range 1024000 -
10244096. Fix the calculation.

CC: stable@vger.kernel.org
Fixes: 8bad6fc813
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2014-06-26 12:30:54 -04:00
Jan Kara
77ea2a4ba6 ext4: Fix block zeroing when punching holes in indirect block files
free_holes_block() passed local variable as a block pointer
to ext4_clear_blocks(). Thus ext4_clear_blocks() zeroed out this local
variable instead of proper place in inode / indirect block. We later
zero out proper place in inode / indirect block but don't dirty the
inode / buffer again which can lead to subtle issues (some changes e.g.
to inode can be lost).

Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2014-06-26 12:28:57 -04:00
Namjae Jeon
e43bb4e612 ext4: decrement free clusters/inodes counters when block group declared bad
We should decrement free clusters counter when block bitmap is marked
as corrupt and free inodes counter when the allocation bitmap is
marked as corrupt to avoid misunderstanding due to incorrect available
size in statfs result.  User can get immediately ENOSPC error from
write begin without reaching for the writepages.

Cc: Darrick J. Wong<darrick.wong@oracle.com>
Reported-by: Amit Sahrawat <amit.sahrawat83@gmail.com>
Signed-off-by: Namjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: Ashish Sangwan <a.sangwan@samsung.com>
2014-06-26 10:11:53 -04:00
Jan Kara
c5c7b8ddfb ext4: Fix buffer double free in ext4_alloc_branch()
Error recovery in ext4_alloc_branch() calls ext4_forget() even for
buffer corresponding to indirect block it did not allocate. This leads
to brelse() being called twice for that buffer (once from ext4_forget()
and once from cleanup in ext4_ind_map_blocks()) leading to buffer use
count misaccounting. Eventually (but often much later because there
are other users of the buffer) we will see messages like:
VFS: brelse: Trying to free free buffer

Another manifestation of this problem is an error:
JBD2 unexpected failure: jbd2_journal_revoke: !buffer_revoked(bh);
inconsistent data on disk

The fix is easy - don't forget buffer we did not allocate. Also add an
explanatory comment because the indexing at ext4_alloc_branch() is
somewhat subtle.

Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@vger.kernel.org
2014-06-15 23:46:28 -04:00
Linus Torvalds
16b9057804 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull vfs updates from Al Viro:
 "This the bunch that sat in -next + lock_parent() fix.  This is the
  minimal set; there's more pending stuff.

  In particular, I really hope to get acct.c fixes merged this cycle -
  we need that to deal sanely with delayed-mntput stuff.  In the next
  pile, hopefully - that series is fairly short and localized
  (kernel/acct.c, fs/super.c and fs/namespace.c).  In this pile: more
  iov_iter work.  Most of prereqs for ->splice_write with sane locking
  order are there and Kent's dio rewrite would also fit nicely on top of
  this pile"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (70 commits)
  lock_parent: don't step on stale ->d_parent of all-but-freed one
  kill generic_file_splice_write()
  ceph: switch to iter_file_splice_write()
  shmem: switch to iter_file_splice_write()
  nfs: switch to iter_splice_write_file()
  fs/splice.c: remove unneeded exports
  ocfs2: switch to iter_file_splice_write()
  ->splice_write() via ->write_iter()
  bio_vec-backed iov_iter
  optimize copy_page_{to,from}_iter()
  bury generic_file_aio_{read,write}
  lustre: get rid of messing with iovecs
  ceph: switch to ->write_iter()
  ceph_sync_direct_write: stop poking into iov_iter guts
  ceph_sync_read: stop poking into iov_iter guts
  new helper: copy_page_from_iter()
  fuse: switch to ->write_iter()
  btrfs: switch to ->write_iter()
  ocfs2: switch to ->write_iter()
  xfs: switch to ->write_iter()
  ...
2014-06-12 10:30:18 -07:00
Al Viro
8d0207652c ->splice_write() via ->write_iter()
iter_file_splice_write() - a ->splice_write() instance that gathers the
pipe buffers, builds a bio_vec-based iov_iter covering those and feeds
it to ->write_iter().  A bunch of simple cases coverted to that...

[AV: fixed the braino spotted by Cyrill]

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2014-06-12 00:18:51 -04:00
Linus Torvalds
f8409abdc5 Clean ups and miscellaneous bug fixes, in particular for the new
collapse_range and zero_range fallocate functions.  In addition,
 improve the scalability of adding and remove inodes from the orphan
 list.
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Merge tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4

Pull ext4 updates from Ted Ts'o:
 "Clean ups and miscellaneous bug fixes, in particular for the new
  collapse_range and zero_range fallocate functions.  In addition,
  improve the scalability of adding and remove inodes from the orphan
  list"

* tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: (25 commits)
  ext4: handle symlink properly with inline_data
  ext4: fix wrong assert in ext4_mb_normalize_request()
  ext4: fix zeroing of page during writeback
  ext4: remove unused local variable "stored" from ext4_readdir(...)
  ext4: fix ZERO_RANGE test failure in data journalling
  ext4: reduce contention on s_orphan_lock
  ext4: use sbi in ext4_orphan_{add|del}()
  ext4: use EXT_MAX_BLOCKS in ext4_es_can_be_merged()
  ext4: add missing BUFFER_TRACE before ext4_journal_get_write_access
  ext4: remove unnecessary double parentheses
  ext4: do not destroy ext4_groupinfo_caches if ext4_mb_init() fails
  ext4: make local functions static
  ext4: fix block bitmap validation when bigalloc, ^flex_bg
  ext4: fix block bitmap initialization under sparse_super2
  ext4: find the group descriptors on a 1k-block bigalloc,meta_bg filesystem
  ext4: avoid unneeded lookup when xattr name is invalid
  ext4: fix data integrity sync in ordered mode
  ext4: remove obsoleted check
  ext4: add a new spinlock i_raw_lock to protect the ext4's raw inode
  ext4: fix locking for O_APPEND writes
  ...
2014-06-08 13:03:35 -07:00
Mel Gorman
2457aec637 mm: non-atomically mark page accessed during page cache allocation where possible
aops->write_begin may allocate a new page and make it visible only to have
mark_page_accessed called almost immediately after.  Once the page is
visible the atomic operations are necessary which is noticable overhead
when writing to an in-memory filesystem like tmpfs but should also be
noticable with fast storage.  The objective of the patch is to initialse
the accessed information with non-atomic operations before the page is
visible.

The bulk of filesystems directly or indirectly use
grab_cache_page_write_begin or find_or_create_page for the initial
allocation of a page cache page.  This patch adds an init_page_accessed()
helper which behaves like the first call to mark_page_accessed() but may
called before the page is visible and can be done non-atomically.

The primary APIs of concern in this care are the following and are used
by most filesystems.

	find_get_page
	find_lock_page
	find_or_create_page
	grab_cache_page_nowait
	grab_cache_page_write_begin

All of them are very similar in detail to the patch creates a core helper
pagecache_get_page() which takes a flags parameter that affects its
behavior such as whether the page should be marked accessed or not.  Then
old API is preserved but is basically a thin wrapper around this core
function.

Each of the filesystems are then updated to avoid calling
mark_page_accessed when it is known that the VM interfaces have already
done the job.  There is a slight snag in that the timing of the
mark_page_accessed() has now changed so in rare cases it's possible a page
gets to the end of the LRU as PageReferenced where as previously it might
have been repromoted.  This is expected to be rare but it's worth the
filesystem people thinking about it in case they see a problem with the
timing change.  It is also the case that some filesystems may be marking
pages accessed that previously did not but it makes sense that filesystems
have consistent behaviour in this regard.

The test case used to evaulate this is a simple dd of a large file done
multiple times with the file deleted on each iterations.  The size of the
file is 1/10th physical memory to avoid dirty page balancing.  In the
async case it will be possible that the workload completes without even
hitting the disk and will have variable results but highlight the impact
of mark_page_accessed for async IO.  The sync results are expected to be
more stable.  The exception is tmpfs where the normal case is for the "IO"
to not hit the disk.

The test machine was single socket and UMA to avoid any scheduling or NUMA
artifacts.  Throughput and wall times are presented for sync IO, only wall
times are shown for async as the granularity reported by dd and the
variability is unsuitable for comparison.  As async results were variable
do to writback timings, I'm only reporting the maximum figures.  The sync
results were stable enough to make the mean and stddev uninteresting.

The performance results are reported based on a run with no profiling.
Profile data is based on a separate run with oprofile running.

async dd
                                    3.15.0-rc3            3.15.0-rc3
                                       vanilla           accessed-v2
ext3    Max      elapsed     13.9900 (  0.00%)     11.5900 ( 17.16%)
tmpfs	Max      elapsed      0.5100 (  0.00%)      0.4900 (  3.92%)
btrfs   Max      elapsed     12.8100 (  0.00%)     12.7800 (  0.23%)
ext4	Max      elapsed     18.6000 (  0.00%)     13.3400 ( 28.28%)
xfs	Max      elapsed     12.5600 (  0.00%)      2.0900 ( 83.36%)

The XFS figure is a bit strange as it managed to avoid a worst case by
sheer luck but the average figures looked reasonable.

        samples percentage
ext3       86107    0.9783  vmlinux-3.15.0-rc4-vanilla        mark_page_accessed
ext3       23833    0.2710  vmlinux-3.15.0-rc4-accessed-v3r25 mark_page_accessed
ext3        5036    0.0573  vmlinux-3.15.0-rc4-accessed-v3r25 init_page_accessed
ext4       64566    0.8961  vmlinux-3.15.0-rc4-vanilla        mark_page_accessed
ext4        5322    0.0713  vmlinux-3.15.0-rc4-accessed-v3r25 mark_page_accessed
ext4        2869    0.0384  vmlinux-3.15.0-rc4-accessed-v3r25 init_page_accessed
xfs        62126    1.7675  vmlinux-3.15.0-rc4-vanilla        mark_page_accessed
xfs         1904    0.0554  vmlinux-3.15.0-rc4-accessed-v3r25 init_page_accessed
xfs          103    0.0030  vmlinux-3.15.0-rc4-accessed-v3r25 mark_page_accessed
btrfs      10655    0.1338  vmlinux-3.15.0-rc4-vanilla        mark_page_accessed
btrfs       2020    0.0273  vmlinux-3.15.0-rc4-accessed-v3r25 init_page_accessed
btrfs        587    0.0079  vmlinux-3.15.0-rc4-accessed-v3r25 mark_page_accessed
tmpfs      59562    3.2628  vmlinux-3.15.0-rc4-vanilla        mark_page_accessed
tmpfs       1210    0.0696  vmlinux-3.15.0-rc4-accessed-v3r25 init_page_accessed
tmpfs         94    0.0054  vmlinux-3.15.0-rc4-accessed-v3r25 mark_page_accessed

[akpm@linux-foundation.org: don't run init_page_accessed() against an uninitialised pointer]
Signed-off-by: Mel Gorman <mgorman@suse.de>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Jan Kara <jack@suse.cz>
Cc: Michal Hocko <mhocko@suse.cz>
Cc: Hugh Dickins <hughd@google.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Theodore Ts'o <tytso@mit.edu>
Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Tested-by: Prabhakar Lad <prabhakar.csengg@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-06-04 16:54:10 -07:00
Matthew Wilcox
1b938c0827 fs/buffer.c: remove block_write_full_page_endio()
The last in-tree caller of block_write_full_page_endio() was removed in
January 2013.  It's time to remove the EXPORT_SYMBOL, which leaves
block_write_full_page() as the only caller of
block_write_full_page_endio(), so inline block_write_full_page_endio()
into block_write_full_page().

Signed-off-by: Matthew Wilcox <matthew.r.wilcox@intel.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Dheeraj Reddy <dheeraj.reddy@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-06-04 16:54:02 -07:00
Linus Torvalds
776edb5931 Merge branch 'locking-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip into next
Pull core locking updates from Ingo Molnar:
 "The main changes in this cycle were:

   - reduced/streamlined smp_mb__*() interface that allows more usecases
     and makes the existing ones less buggy, especially in rarer
     architectures

   - add rwsem implementation comments

   - bump up lockdep limits"

* 'locking-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (33 commits)
  rwsem: Add comments to explain the meaning of the rwsem's count field
  lockdep: Increase static allocations
  arch: Mass conversion of smp_mb__*()
  arch,doc: Convert smp_mb__*()
  arch,xtensa: Convert smp_mb__*()
  arch,x86: Convert smp_mb__*()
  arch,tile: Convert smp_mb__*()
  arch,sparc: Convert smp_mb__*()
  arch,sh: Convert smp_mb__*()
  arch,score: Convert smp_mb__*()
  arch,s390: Convert smp_mb__*()
  arch,powerpc: Convert smp_mb__*()
  arch,parisc: Convert smp_mb__*()
  arch,openrisc: Convert smp_mb__*()
  arch,mn10300: Convert smp_mb__*()
  arch,mips: Convert smp_mb__*()
  arch,metag: Convert smp_mb__*()
  arch,m68k: Convert smp_mb__*()
  arch,m32r: Convert smp_mb__*()
  arch,ia64: Convert smp_mb__*()
  ...
2014-06-03 12:57:53 -07:00
Zheng Liu
bd9db175dd ext4: handle symlink properly with inline_data
This commit tries to fix a bug that we can't read symlink properly with
inline data feature when the length of symlink is greater than 60 bytes
but less than extra space.

The key issue is in ext4_inode_is_fast_symlink() that it doesn't check
whether or not an inode has inline data.  When the user creates a new
symlink, an inode will be allocated with MAY_INLINE_DATA flag.  Then
symlink will be stored in ->i_block and extended attribute space.  In
the mean time, this inode is with inline data flag.  After remounting
it, ext4_inode_is_fast_symlink() function thinks that this inode is a
fast symlink so that the data in ->i_block is copied to the user, and
the data in extra space is trimmed.  In fact this inode should be as a
normal symlink.

The following script can hit this bug.

  #!/bin/bash

  cd ${MNT}
  filename=ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789
  rm -rf test
  mkdir test
  cd test
  echo "hello" >$filename
  ln -s $filename symlinkfile
  cd
  sudo umount /mnt/sda1
  sudo mount -t ext4 /dev/sda1 /mnt/sda1
  readlink /mnt/sda1/test/symlinkfile

After applying this patch, it will break the assumption in e2fsck
because the original implementation doesn't want to support symlink
with inline data.

Reported-by: "Darrick J. Wong" <darrick.wong@oracle.com>
Reported-by: Ian Nartowicz <claws@nartowicz.co.uk>
Cc: Ian Nartowicz <claws@nartowicz.co.uk>
Cc: Tao Ma <tm@tao.ma>
Cc: "Darrick J. Wong" <darrick.wong@oracle.com>
Cc: Andreas Dilger <adilger.kernel@dilger.ca>
Signed-off-by: Zheng Liu <wenqing.lz@taobao.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2014-06-02 10:48:22 -04:00
Maurizio Lombardi
b5b6077855 ext4: fix wrong assert in ext4_mb_normalize_request()
The variable "size" is expressed as number of blocks and not as
number of clusters, this could trigger a kernel panic when using
ext4 with the size of a cluster different from the size of a block.

Cc: stable@vger.kernel.org
Signed-off-by: Maurizio Lombardi <mlombard@redhat.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2014-05-27 12:48:56 -04:00
Jan Kara
eeece469de ext4: fix zeroing of page during writeback
Tail of a page straddling inode size must be zeroed when being written
out due to POSIX requirement that modifications of mmaped page beyond
inode size must not be written to the file. ext4_bio_write_page() did
this only for blocks fully beyond inode size but didn't properly zero
blocks partially beyond inode size. Fix this.

The problem has been uncovered by mmap_11-4 test in openposix test suite
(part of LTP).

Reported-by: Xiaoguang Wang <wangxg.fnst@cn.fujitsu.com>
Fixes: 5a0dc7365c
Fixes: bd2d0210cf
CC: stable@vger.kernel.org
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2014-05-27 12:48:55 -04:00
Giedrius Rekasius
aa13d5f67c ext4: remove unused local variable "stored" from ext4_readdir(...)
Remove local variable "stored" from ext4_readdir(...). This variable 
gets initialized but is never used inside the function.

Signed-off-by: Giedrius Rekasius <giedrius.rekasius@gmail.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2014-05-27 12:48:55 -04:00
Namjae Jeon
e1ee60fd89 ext4: fix ZERO_RANGE test failure in data journalling
xfstests generic/091 is failing when mounting ext4 with data=journal.
I think that this regression is same problem that occurred prior to collapse
range issue. So ZERO RANGE also need to call ext4_force_commit as
collapse range.

Cc: stable@vger.kernel.org
Signed-off-by: Namjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: Ashish Sangwan <a.sangwan@samsung.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2014-05-27 12:48:55 -04:00
Jan Kara
d745a8c20c ext4: reduce contention on s_orphan_lock
Shuffle code around in ext4_orphan_add() and ext4_orphan_del() so that
we avoid taking global s_orphan_lock in some cases and hold it for
shorter time in other cases.

Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2014-05-26 11:56:53 -04:00
Jan Kara
cd2c080c33 ext4: use sbi in ext4_orphan_{add|del}()
Use sbi pointer consistently in ext4_orphan_del() instead of opencoding
it sometimes. Also ext4_orphan_add() uses EXT4_SB(sb) often so create
sbi variable for it as well and use it.

Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2014-05-26 11:39:17 -04:00
Lukas Czerner
0baaea6400 ext4: use EXT_MAX_BLOCKS in ext4_es_can_be_merged()
In ext4_es_can_be_merged() when checking whether we can merge two
extents we should use EXT_MAX_BLOCKS instead of defining it manually.
Also if it is really the case we should notify userspace because clearly
there is a bug in extent status tree implementation since this should
never happen.

Signed-off-by: Lukas Czerner <lczerner@redhat.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Reviewed-by: Zheng Liu <wenqing.lz@taobao.com>
2014-05-12 22:21:43 -04:00
liang xie
5d60125530 ext4: add missing BUFFER_TRACE before ext4_journal_get_write_access
Make them more consistently

Signed-off-by: xieliang <xieliang@xiaomi.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2014-05-12 22:06:43 -04:00
Lukas Czerner
c8b459f492 ext4: remove unnecessary double parentheses
Signed-off-by: Lukas Czerner <lczerner@redhat.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2014-05-12 12:55:07 -04:00
Andrey Tsyvarev
029b10c5a8 ext4: do not destroy ext4_groupinfo_caches if ext4_mb_init() fails
Caches from 'ext4_groupinfo_caches' may be in use by other mounts,
which have already existed.  So, it is incorrect to destroy them when
newly requested mount fails.

Found by Linux File System Verification project (linuxtesting.org).

Signed-off-by: Andrey Tsyvarev <tsyvarev@ispras.ru>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Reviewed-by: Lukas Czerner <lczerner@redhat.com>
2014-05-12 12:34:21 -04:00
Stephen Hemminger
c197855ea1 ext4: make local functions static
I have been running make namespacecheck to look for unneeded globals, and
found these in ext4.

Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2014-05-12 10:50:23 -04:00
Darrick J. Wong
e674e5cbd0 ext4: fix block bitmap validation when bigalloc, ^flex_bg
On a bigalloc,^flex_bg filesystem, the ext4_valid_block_bitmap
function fails to convert from blocks to clusters when spot-checking
the validity of the bitmap block that we've just read from disk.  This
causes ext4 to think that the bitmap is garbage, which results in the
block group being taken offline when it's not necessary.  Add in the
necessary EXT4_B2C() calls to perform the conversions.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2014-05-12 10:17:55 -04:00
Darrick J. Wong
1beeef1b56 ext4: fix block bitmap initialization under sparse_super2
The ext4_bg_has_super() function doesn't know about the new rules for
where backup superblocks go on a sparse_super2 filesystem.  Therefore,
block bitmap initialization doesn't know that it shouldn't reserve
space for backups in groups that are never going to contain backups.
The result of this is e2fsck complaining about the block bitmap being
incorrect (fortunately not in a way that results in cross-linked
files), so fix the whole thing.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2014-05-12 10:16:06 -04:00
Darrick J. Wong
bd63f6b0cd ext4: find the group descriptors on a 1k-block bigalloc,meta_bg filesystem
On a filesystem with a 1k block size, the group descriptors live in
block 2, not block 1.  If the filesystem has bigalloc,meta_bg set,
however, the calculation of the group descriptor table location does
not take this into account and returns the wrong block number.  Fix
the calculation to return the correct value for this case.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2014-05-12 10:06:27 -04:00
Zhang Zhen
230b8c1a7b ext4: avoid unneeded lookup when xattr name is invalid
In ext4_xattr_set_handle() we have checked the xattr name's length. So
we should also check it in ext4_xattr_get() to avoid unneeded lookup
caused by invalid name.

Signed-off-by: Zhang Zhen <zhenzhang.zhang@huawei.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2014-05-12 09:57:59 -04:00
Namjae Jeon
1c8349a171 ext4: fix data integrity sync in ordered mode
When we perform a data integrity sync we tag all the dirty pages with
PAGECACHE_TAG_TOWRITE at start of ext4_da_writepages.  Later we check
for this tag in write_cache_pages_da and creates a struct
mpage_da_data containing contiguously indexed pages tagged with this
tag and sync these pages with a call to mpage_da_map_and_submit.  This
process is done in while loop until all the PAGECACHE_TAG_TOWRITE
pages are synced. We also do journal start and stop in each iteration.
journal_stop could initiate journal commit which would call
ext4_writepage which in turn will call ext4_bio_write_page even for
delayed OR unwritten buffers. When ext4_bio_write_page is called for
such buffers, even though it does not sync them but it clears the
PAGECACHE_TAG_TOWRITE of the corresponding page and hence these pages
are also not synced by the currently running data integrity sync. We
will end up with dirty pages although sync is completed.

This could cause a potential data loss when the sync call is followed
by a truncate_pagecache call, which is exactly the case in
collapse_range.  (It will cause generic/127 failure in xfstests)

To avoid this issue, we can use set_page_writeback_keepwrite instead of
set_page_writeback, which doesn't clear TOWRITE tag.

Cc: stable@vger.kernel.org
Signed-off-by: Namjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: Ashish Sangwan <a.sangwan@samsung.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Reviewed-by: Jan Kara <jack@suse.cz>
2014-05-12 08:12:25 -04:00
Al Viro
9b884164d5 convert ext4 to ->write_iter()
unfortunately, Ted's changes to ext4_file_write() are *still* an
incomplete fix - playing with rlimits can let you smuggle an
unaligned request past the checks.  So there almost certainly
will be more merge PITA around that place...

[fix from Peter Ujfalusi <peter.ujfalusi@ti.com> folded]

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2014-05-06 17:39:36 -04:00
Al Viro
a832475488 Merge ext4 changes in ext4_file_write() into for-next
From ext4.git#dev, needed for switch of ext4 to ->write_iter() ;-/
2014-05-06 17:38:41 -04:00
Al Viro
aad4f8bb42 switch simple generic_file_aio_read() users to ->read_iter()
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2014-05-06 17:37:55 -04:00
Al Viro
31b140398c switch {__,}blockdev_direct_IO() to iov_iter
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2014-05-06 17:32:46 -04:00
Al Viro
a6cbcd4a4a get rid of pointless iov_length() in ->direct_IO()
all callers have iov_length(iter->iov, iter->nr_segs) == iov_iter_count(iter)

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2014-05-06 17:32:45 -04:00
Al Viro
16b1f05d7f ext4: switch the guts of ->direct_IO() to iov_iter
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2014-05-06 17:32:45 -04:00
Al Viro
d8d3d94b80 pass iov_iter to ->direct_IO()
unmodified, for now

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2014-05-06 17:32:44 -04:00
Dmitry Monakhov
236f5ecb4a ext4: remove obsoleted check
BH can not be NULL at this point, ext4_read_dirblock() always return
non null value, and we already have done all necessery checks.

Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2014-04-21 14:38:14 -04:00
Theodore Ts'o
202ee5df38 ext4: add a new spinlock i_raw_lock to protect the ext4's raw inode
To avoid potential data races, use a spinlock which protects the raw
(on-disk) inode.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Reviewed-by: Jan Kara <jack@suse.cz>
2014-04-21 14:37:55 -04:00