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2311 commits

Author SHA1 Message Date
Zheng Liu
e963bb1de4 ext4: improve extents status tree trace point
This commit improves the trace point of extents status tree.  We rename
trace_ext4_es_shrink_enter in ext4_es_count() because it is also used
in ext4_es_scan() and we can not identify them from the result.

Further this commit fixes a variable name in trace point in order to
keep consistency with others.

Cc: Andreas Dilger <adilger.kernel@dilger.ca>
Cc: Jan Kara <jack@suse.cz>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Zheng Liu <wenqing.lz@taobao.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2014-09-01 22:22:13 -04:00
Seunghun Lee
d91bd2c1d7 ext4: fix comments about get_blocks
get_blocks is renamed to get_block.

Signed-off-by: Seunghun Lee <waydi1@gmail.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2014-09-01 22:15:30 -04:00
Darrick J. Wong
45f1a9c3f6 ext4: enable block_validity by default
Enable by default the block_validity feature, which checks for
collisions between newly allocated blocks and critical system
metadata.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2014-09-01 21:34:09 -04:00
Theodore Ts'o
ed8a1a766a ext4: rename ext4_ext_find_extent() to ext4_find_extent()
Make the function name less redundant.

Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2014-09-01 14:43:09 -04:00
Theodore Ts'o
3bdf14b4d7 ext4: reuse path object in ext4_move_extents()
Reuse the path object in ext4_move_extents() so we don't unnecessarily
free and reallocate it.

Also clean up the get_ext_path() wrapper so that it has the same
semantics of freeing the path object on error as ext4_ext_find_extent().

Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2014-09-01 14:42:09 -04:00
Theodore Ts'o
ee4bd0d963 ext4: reuse path object in ext4_ext_shift_extents()
Now that the semantics of ext4_ext_find_extent() are much cleaner,
it's safe and more efficient to reuse the path object across the
multiple calls to ext4_ext_find_extent() in ext4_ext_shift_extents().

Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2014-09-01 14:41:09 -04:00
Theodore Ts'o
10809df84a ext4: teach ext4_ext_find_extent() to realloc path if necessary
This adds additional safety in case for some reason we end reusing a
path structure which isn't big enough for current depth of the inode.

Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2014-09-01 14:40:09 -04:00
Theodore Ts'o
b7ea89ad0a ext4: allow a NULL argument to ext4_ext_drop_refs()
Teach ext4_ext_drop_refs() to accept a NULL argument, much like
kfree().  This allows us to drop a lot of checks to make sure path is
non-NULL before calling ext4_ext_drop_refs().

Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2014-09-01 14:39:09 -04:00
Theodore Ts'o
523f431ccf ext4: call ext4_ext_drop_refs() from ext4_ext_find_extent()
In nearly all of the calls to ext4_ext_find_extent() where the caller
is trying to recycle the path object, ext4_ext_drop_refs() gets called
to release the buffer heads before the path object gets overwritten.
To simplify things for the callers, and to avoid the possibility of a
memory leak, make ext4_ext_find_extent() responsible for dropping the
buffers.

Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2014-09-01 14:38:09 -04:00
Theodore Ts'o
dfe5080939 ext4: drop EXT4_EX_NOFREE_ON_ERR from rest of extents handling code
Drop EXT4_EX_NOFREE_ON_ERR from ext4_ext_create_new_leaf(),
ext4_split_extent(), ext4_convert_unwritten_extents_endio().

This requires fixing all of their callers to potentially
ext4_ext_find_extent() to free the struct ext4_ext_path object in case
of an error, and there are interlocking dependencies all the way up to
ext4_ext_map_blocks(), ext4_swap_extents(), and
ext4_ext_remove_space().

Once this is done, we can drop the EXT4_EX_NOFREE_ON_ERR flag since it
is no longer necessary.

Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2014-09-01 14:37:09 -04:00
Theodore Ts'o
4f224b8b7b ext4: drop EXT4_EX_NOFREE_ON_ERR in convert_initialized_extent()
Transfer responsibility of freeing struct ext4_ext_path on error to
ext4_ext_find_extent().

Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2014-09-01 14:36:09 -04:00
Theodore Ts'o
e8b83d9303 ext4: collapse ext4_convert_initialized_extents()
The function ext4_convert_initialized_extents() is only called by a
single function --- ext4_ext_convert_initalized_extents().  Inline the
code and get rid of the unnecessary bits in order to simplify the code.

Rename ext4_ext_convert_initalized_extents() to
convert_initalized_extents() since it's a static function that is
actually only used in a single caller, ext4_ext_map_blocks().

Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2014-09-01 14:35:09 -04:00
Theodore Ts'o
705912ca95 ext4: teach ext4_ext_find_extent() to free path on error
Right now, there are a places where it is all to easy to leak memory
on an error path, via a usage like this:

	struct ext4_ext_path *path = NULL

	while (...) {
		...
		path = ext4_ext_find_extent(inode, block, path, 0);
		if (IS_ERR(path)) {
			/* oops, if path was non-NULL before the call to
			   ext4_ext_find_extent, we've leaked it!  :-(  */
			...
			return PTR_ERR(path);
		}
		...
	}

Unfortunately, there some code paths where we are doing the following
instead:

	path = ext4_ext_find_extent(inode, block, orig_path, 0);

and where it's important that we _not_ free orig_path in the case
where ext4_ext_find_extent() returns an error.

So change the function signature of ext4_ext_find_extent() so that it
takes a struct ext4_ext_path ** for its third argument, and by
default, on an error, it will free the struct ext4_ext_path, and then
zero out the struct ext4_ext_path * pointer.  In order to avoid
causing problems, we add a flag EXT4_EX_NOFREE_ON_ERR which causes
ext4_ext_find_extent() to use the original behavior of forcing the
caller to deal with freeing the original path pointer on the error
case.

The goal is to get rid of EXT4_EX_NOFREE_ON_ERR entirely, but this
allows for a gentle transition and makes the patches easier to verify.

Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2014-09-01 14:34:09 -04:00
Theodore Ts'o
bd30d702fc ext4: fix accidental flag aliasing in ext4_map_blocks flags
Commit b8a8684502 introduced an accidental flag aliasing between
EXT4_EX_NOCACHE and EXT4_GET_BLOCKS_CONVERT_UNWRITTEN.

Fortunately, this didn't introduce any untorward side effects --- we
got lucky.  Nevertheless, fix this and leave a warning to hopefully
avoid this from happening in the future.

Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2014-09-01 14:33:09 -04:00
Theodore Ts'o
713e8dde3e ext4: fix ZERO_RANGE bug hidden by flag aliasing
We accidently aliased EXT4_EX_NOCACHE and EXT4_GET_CONVERT_UNWRITTEN
falgs, which apparently was hiding a bug that was unmasked when this
flag aliasing issue was addressed (see the subsequent commit).  The
reproduction case was:

   fsx -N 10000 -l 500000 -r 4096 -t 4096 -w 4096 -Z -R -W /vdb/junk

... which would cause fsx to report corruption in the data file.

The fix we have is a bit of an overkill, but I'd much rather be
conservative for now, and we can optimize ZERO_RANGE_FL handling
later.  The fact that we need to zap the extent_status cache for the
inode is unfortunate, but correctness is far more important than
performance.

Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: Namjae Jeon <namjae.jeon@samsung.com>
2014-09-01 14:32:09 -04:00
Theodore Ts'o
19008f6dfa ext4: fix ext4_swap_extents() error handling
If ext4_ext_find_extent() returns an error, we have to clear path1 or
path2 or else we would end up trying to free an ERR_PTR, which would
be bad.

Also eliminate some redundant code and mark the error paths as unlikely()

Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2014-08-31 15:03:14 -04:00
Dmitry Monakhov
fcf6b1b729 ext4: refactor ext4_move_extents code base
ext4_move_extents is too complex for review. It has duplicate almost
each function available in the rest of other codebase. It has useless
artificial restriction orig_offset == donor_offset. But in fact logic
of ext4_move_extents is very simple:

Iterate extents one by one (similar to ext4_fill_fiemap_extents)
   ->Iterate each page covered extent (similar to generic_perform_write)
     ->swap extents for covered by page (can be shared with IOC_MOVE_DATA)

Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2014-08-30 23:52:19 -04:00
Dmitry Monakhov
f8fb4f4150 ext4: use ext4_ext_next_allocated_block instead of mext_next_extent
This allows us to make mext_next_extent static and potentially get rid
of it.

Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2014-08-30 23:50:56 -04:00
Dmitry Monakhov
ee124d2746 ext4: use ext4_update_i_disksize instead of opencoded ones
Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2014-08-30 23:34:06 -04:00
Wang Shilong
52c826db6d ext4: remove a duplicate call in ext4_init_new_dir()
ext4_journal_get_write_access() has just been called in ext4_append()
calling it again here is duplicated.

Signed-off-by: Wang Shilong <wshilong@ddn.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2014-08-29 23:20:44 -04:00
Theodore Ts'o
f8b3b59d4d ext4: convert do_split() to use the ERR_PTR convention
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2014-08-29 20:52:18 -04:00
Theodore Ts'o
dd73b5d5cb ext4: convert dx_probe() to use the ERR_PTR convention
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2014-08-29 20:52:17 -04:00
Theodore Ts'o
1c2150283c ext4: convert ext4_bread() to use the ERR_PTR convention
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2014-08-29 20:52:15 -04:00
Theodore Ts'o
1056008226 ext4: convert ext4_getblk() to use the ERR_PTR convention
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2014-08-29 20:51:32 -04:00
Theodore Ts'o
537d8f9380 ext4: convert ext4_dx_find_entry() to use the ERR_PTR convention
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2014-08-29 20:49:51 -04:00
Darrick J. Wong
d80d448c6c ext4: fix same-dir rename when inline data directory overflows
When performing a same-directory rename, it's possible that adding or
setting the new directory entry will cause the directory to overflow
the inline data area, which causes the directory to be converted to an
extent-based directory.  Under this circumstance it is necessary to
re-read the directory when deleting the old dirent because the "old
directory" context still points to i_block in the inode table, which
is now an extent tree root!  The delete fails with an FS error, and
the subsequent fsck complains about incorrect link counts and
hardlinked directories.

Test case (originally found with flat_dir_test in the metadata_csum
test program):

# mkfs.ext4 -O inline_data /dev/sda
# mount /dev/sda /mnt
# mkdir /mnt/x
# touch /mnt/x/changelog.gz /mnt/x/copyright /mnt/x/README.Debian
# sync
# for i in /mnt/x/*; do mv $i $i.longer; done
# ls -la /mnt/x/
total 0
-rw-r--r-- 1 root root 0 Aug 25 12:03 changelog.gz.longer
-rw-r--r-- 1 root root 0 Aug 25 12:03 copyright
-rw-r--r-- 1 root root 0 Aug 25 12:03 copyright.longer
-rw-r--r-- 1 root root 0 Aug 25 12:03 README.Debian.longer

(Hey!  Why are there four files now??)

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@vger.kernel.org
2014-08-28 22:22:29 -04:00
Darrick J. Wong
db9ee22036 jbd2: fix descriptor block size handling errors with journal_csum
It turns out that there are some serious problems with the on-disk
format of journal checksum v2.  The foremost is that the function to
calculate descriptor tag size returns sizes that are too big.  This
causes alignment issues on some architectures and is compounded by the
fact that some parts of jbd2 use the structure size (incorrectly) to
determine the presence of a 64bit journal instead of checking the
feature flags.

Therefore, introduce journal checksum v3, which enlarges the
descriptor block tag format to allow for full 32-bit checksums of
journal blocks, fix the journal tag function to return the correct
sizes, and fix the jbd2 recovery code to use feature flags to
determine 64bitness.

Add a few function helpers so we don't have to open-code quite so
many pieces.

Switching to a 16-byte block size was found to increase journal size
overhead by a maximum of 0.1%, to convert a 32-bit journal with no
checksumming to a 32-bit journal with checksum v3 enabled.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reported-by: TR Reardon <thomas_reardon@hotmail.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@vger.kernel.org
2014-08-28 22:22:29 -04:00
Dmitry Monakhov
6603120e96 ext4: update i_disksize coherently with block allocation on error path
In case of delalloc block i_disksize may be less than i_size. So we
have to update i_disksize each time we allocated and submitted some
blocks beyond i_disksize.  We weren't doing this on the error paths,
so fix this.

testcase: xfstest generic/019

Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@vger.kernel.org
2014-08-28 22:20:41 -04:00
Dmitry Monakhov
c174e6d697 ext4: fix transaction issues for ext4_fallocate and ext_zero_range
After commit f282ac19d8 we use different transactions for
preallocation and i_disksize update which result in complain from fsck
after power-failure.  spotted by generic/019. IMHO this is regression
because fs becomes inconsistent, even more 'e2fsck -p' will no longer
works (which drives admins go crazy) Same transaction requirement
applies ctime,mtime updates

testcase: xfstest generic/019

Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@vger.kernel.org
2014-08-27 18:40:00 -04:00
Dmitry Monakhov
69dc953640 ext4: fix incorect journal credits reservation in ext4_zero_range
Currently we reserve only 4 blocks but in worst case scenario
ext4_zero_partial_blocks() may want to zeroout and convert two
non adjacent blocks.

Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@vger.kernel.org
2014-08-27 18:33:49 -04:00
Dmitry Monakhov
4631dbf677 ext4: move i_size,i_disksize update routines to helper function
Cc: stable@vger.kernel.org # needed for bug fix patches
Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2014-08-23 17:48:28 -04:00
Theodore Ts'o
c99d1e6e83 ext4: fix BUG_ON in mb_free_blocks()
If we suffer a block allocation failure (for example due to a memory
allocation failure), it's possible that we will call
ext4_discard_allocated_blocks() before we've actually allocated any
blocks.  In that case, fe_len and fe_start in ac->ac_f_ex will still
be zero, and this will result in mb_free_blocks(inode, e4b, 0, 0)
triggering the BUG_ON on mb_free_blocks():

	BUG_ON(last >= (sb->s_blocksize << 3));

Fix this by bailing out of ext4_discard_allocated_blocks() if fs_len
is zero.

Also fix a missing ext4_mb_unload_buddy() call in
ext4_discard_allocated_blocks().

Google-Bug-Id: 16844242

Fixes: 86f0afd463
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@vger.kernel.org
2014-08-23 17:47:28 -04:00
Theodore Ts'o
36de928641 ext4: propagate errors up to ext4_find_entry()'s callers
If we run into some kind of error, such as ENOMEM, while calling
ext4_getblk() or ext4_dx_find_entry(), we need to make sure this error
gets propagated up to ext4_find_entry() and then to its callers.  This
way, transient errors such as ENOMEM can get propagated to the VFS.
This is important so that the system calls return the appropriate
error, and also so that in the case of ext4_lookup(), we return an
error instead of a NULL inode, since that will result in a negative
dentry cache entry that will stick around long past the OOM condition
which caused a transient ENOMEM error.

Google-Bug-Id: #17142205

Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@vger.kernel.org
2014-08-23 17:47:19 -04:00
Linus Torvalds
f6f993328b Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull vfs updates from Al Viro:
 "Stuff in here:

   - acct.c fixes and general rework of mnt_pin mechanism.  That allows
     to go for delayed-mntput stuff, which will permit mntput() on deep
     stack without worrying about stack overflows - fs shutdown will
     happen on shallow stack.  IOW, we can do Eric's umount-on-rmdir
     series without introducing tons of stack overflows on new mntput()
     call chains it introduces.
   - Bruce's d_splice_alias() patches
   - more Miklos' rename() stuff.
   - a couple of regression fixes (stable fodder, in the end of branch)
     and a fix for API idiocy in iov_iter.c.

  There definitely will be another pile, maybe even two.  I'd like to
  get Eric's series in this time, but even if we miss it, it'll go right
  in the beginning of for-next in the next cycle - the tricky part of
  prereqs is in this pile"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (40 commits)
  fix copy_tree() regression
  __generic_file_write_iter(): fix handling of sync error after DIO
  switch iov_iter_get_pages() to passing maximal number of pages
  fs: mark __d_obtain_alias static
  dcache: d_splice_alias should detect loops
  exportfs: update Exporting documentation
  dcache: d_find_alias needn't recheck IS_ROOT && DCACHE_DISCONNECTED
  dcache: remove unused d_find_alias parameter
  dcache: d_obtain_alias callers don't all want DISCONNECTED
  dcache: d_splice_alias should ignore DCACHE_DISCONNECTED
  dcache: d_splice_alias mustn't create directory aliases
  dcache: close d_move race in d_splice_alias
  dcache: move d_splice_alias
  namei: trivial fix to vfs_rename_dir comment
  VFS: allow ->d_manage() to declare -EISDIR in rcu_walk mode.
  cifs: support RENAME_NOREPLACE
  hostfs: support rename flags
  shmem: support RENAME_EXCHANGE
  shmem: support RENAME_NOREPLACE
  btrfs: add RENAME_NOREPLACE
  ...
2014-08-11 11:44:11 -07:00
Miklos Szeredi
7177a9c4b5 fs: call rename2 if exists
Christoph Hellwig suggests:

1) make vfs_rename call ->rename2 if it exists instead of ->rename
2) switch all filesystems that you're adding NOREPLACE support for to
   use ->rename2
3) see how many ->rename instances we'll have left after a few
   iterations of 2.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2014-08-07 14:40:09 -04:00
Theodore Ts'o
86f0afd463 ext4: fix ext4_discard_allocated_blocks() if we can't allocate the pa struct
If there is a failure while allocating the preallocation structure, a
number of blocks can end up getting marked in the in-memory buddy
bitmap, and then not getting released.  This can result in the
following corruption getting reported by the kernel:

EXT4-fs error (device sda3): ext4_mb_generate_buddy:758: group 1126,
12793 clusters in bitmap, 12729 in gd

In that case, we need to release the blocks using mb_free_blocks().

Tested: fs smoke test; also demonstrated that with injected errors,
	the file system is no longer getting corrupted

Google-Bug-Id: 16657874

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Cc: stable@vger.kernel.org
2014-07-30 22:17:17 -04:00
Namjae Jeon
ee98fa3a8b ext4: fix COLLAPSE RANGE test for bigalloc file systems
Blocks in collapse range should be collapsed per cluster unit when
bigalloc is enable. If bigalloc is not enable, EXT4_CLUSTER_SIZE will
be same with EXT4_BLOCK_SIZE.

With this bug fixed, patch enables COLLAPSE_RANGE for bigalloc, which
fixes a large number of xfstest failures which use fsx.

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>
2014-07-29 10:45:31 -04:00
Darrick J. Wong
40b163f1c4 ext4: check inline directory before converting
Before converting an inline directory to a regular directory, check
the directory entries to make sure they're not obviously broken.
This helps us to avoid a BUG_ON if one of the dirents is trashed.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Andreas Dilger <adilger@dilger.ca>
2014-07-28 13:06:26 -04:00
Dmitry Monakhov
6e2631463f ext4: fix incorrect locking in move_extent_per_page
If we have to copy data we must drop i_data_sem because of
get_blocks() will be called inside mext_page_mkuptodate(), but later we must
reacquire it again because we are about to change extent's tree

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 22:32:27 -04:00
Dmitry Monakhov
29faed1638 ext4: use correct depth value
Inode's depth can be changed from here:
ext4_ext_try_to_merge() ->ext4_ext_try_to_merge_up()
We must use correct value.

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 22:30:29 -04:00
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