Commit Graph

1868 Commits

Author SHA1 Message Date
Linus Torvalds
d895cb1af1 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull vfs pile (part one) from Al Viro:
 "Assorted stuff - cleaning namei.c up a bit, fixing ->d_name/->d_parent
  locking violations, etc.

  The most visible changes here are death of FS_REVAL_DOT (replaced with
  "has ->d_weak_revalidate()") and a new helper getting from struct file
  to inode.  Some bits of preparation to xattr method interface changes.

  Misc patches by various people sent this cycle *and* ocfs2 fixes from
  several cycles ago that should've been upstream right then.

  PS: the next vfs pile will be xattr stuff."

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (46 commits)
  saner proc_get_inode() calling conventions
  proc: avoid extra pde_put() in proc_fill_super()
  fs: change return values from -EACCES to -EPERM
  fs/exec.c: make bprm_mm_init() static
  ocfs2/dlm: use GFP_ATOMIC inside a spin_lock
  ocfs2: fix possible use-after-free with AIO
  ocfs2: Fix oops in ocfs2_fast_symlink_readpage() code path
  get_empty_filp()/alloc_file() leave both ->f_pos and ->f_version zero
  target: writev() on single-element vector is pointless
  export kernel_write(), convert open-coded instances
  fs: encode_fh: return FILEID_INVALID if invalid fid_type
  kill f_vfsmnt
  vfs: kill FS_REVAL_DOT by adding a d_weak_revalidate dentry op
  nfsd: handle vfs_getattr errors in acl protocol
  switch vfs_getattr() to struct path
  default SET_PERSONALITY() in linux/elf.h
  ceph: prepopulate inodes only when request is aborted
  d_hash_and_lookup(): export, switch open-coded instances
  9p: switch v9fs_set_create_acl() to inode+fid, do it before d_instantiate()
  9p: split dropping the acls from v9fs_set_create_acl()
  ...
2013-02-26 20:16:07 -08:00
Linus Torvalds
6515925b82 The one new feature added in this patch series is the ability to use
the "punch hole" functionality for inodes that are not using extent
 maps.
 
 In the bug fix category, we fixed some races in the AIO and fstrim
 code, and some potential NULL pointer dereferences and memory leaks in
 error handling code paths.
 
 In the optimization category, we fixed a performance regression in the
 jbd2 layer introduced by commit d9b0193 (introduced in v3.0) which
 shows up in the AIM7 benchmark.  We also further optimized jbd2 by
 minimize the amount of time that transaction handles are held active.
 
 This patch series also features some additional enhancement of the
 extent status tree, which is now used to cache extent information in a
 more efficient/compact form than what we use on-disk.
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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 Theodore Ts'o:
 "The one new feature added in this patch series is the ability to use
  the "punch hole" functionality for inodes that are not using extent
  maps.

  In the bug fix category, we fixed some races in the AIO and fstrim
  code, and some potential NULL pointer dereferences and memory leaks in
  error handling code paths.

  In the optimization category, we fixed a performance regression in the
  jbd2 layer introduced by commit d9b01934d5 ("jbd: fix fsync() tid
  wraparound bug", introduced in v3.0) which shows up in the AIM7
  benchmark.  We also further optimized jbd2 by minimize the amount of
  time that transaction handles are held active.

  This patch series also features some additional enhancement of the
  extent status tree, which is now used to cache extent information in a
  more efficient/compact form than what we use on-disk."

* tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: (65 commits)
  ext4: fix free clusters calculation in bigalloc filesystem
  ext4: no need to remove extent if len is 0 in ext4_es_remove_extent()
  ext4: fix xattr block allocation/release with bigalloc
  ext4: reclaim extents from extent status tree
  ext4: adjust some functions for reclaiming extents from extent status tree
  ext4: remove single extent cache
  ext4: lookup block mapping in extent status tree
  ext4: track all extent status in extent status tree
  ext4: let ext4_ext_map_blocks return EXT4_MAP_UNWRITTEN flag
  ext4: rename and improbe ext4_es_find_extent()
  ext4: add physical block and status member into extent status tree
  ext4: refine extent status tree
  ext4: use ERR_PTR() abstraction for ext4_append()
  ext4: refactor code to read directory blocks into ext4_read_dirblock()
  ext4: add debugging context for warning in ext4_da_update_reserve_space()
  ext4: use KERN_WARNING for warning messages
  jbd2: use module parameters instead of debugfs for jbd_debug
  ext4: use module parameters instead of debugfs for mballoc_debug
  ext4: start handle at the last possible moment when creating inodes
  ext4: fix the number of credits needed for acl ops with inline data
  ...
2013-02-26 14:52:45 -08:00
Linus Torvalds
bbbd27e694 Merge branch 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs
Pull ext2, ext3, udf updates from Jan Kara:
 "Several UDF fixes, a support for UDF extent cache, and couple of ext2
  and ext3 cleanups and minor fixes"

* 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs:
  Ext2: remove the static function release_blocks to optimize the kernel
  Ext2: mark inode dirty after the function dquot_free_block_nodirty is called
  Ext2: remove the overhead check about sb in the function ext2_new_blocks
  udf: Remove unused s_extLength from udf_bitmap
  udf: Make s_block_bitmap standard array
  udf: Fix bitmap overflow on large filesystems with small block size
  udf: add extent cache support in case of file reading
  udf: Write LVID to disk after opening / closing
  Ext3: return ENOMEM rather than EIO if sb_getblk fails
  Ext2: return ENOMEM rather than EIO if sb_getblk fails
  Ext3: use unlikely to improve the efficiency of the kernel
  Ext2: use unlikely to improve the efficiency of the kernel
  Ext3: add necessary check in case IO error happens
  Ext2: free memory allocated and forget buffer head when io error happens
  ext3: Fix memory leak when quota options are specified multiple times
  ext3, ext4, ocfs2: remove unused macro NAMEI_RA_INDEX
2013-02-26 14:51:52 -08:00
Al Viro
496ad9aa8e new helper: file_inode(file)
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-02-22 23:31:31 -05:00
Lukas Czerner
304e220f08 ext4: fix free clusters calculation in bigalloc filesystem
ext4_has_free_clusters() should tell us whether there is enough free
clusters to allocate, however number of free clusters in the file system
is converted to blocks using EXT4_C2B() which is not only wrong use of
the macro (we should have used EXT4_NUM_B2C) but it's also completely
wrong concept since everything else is in cluster units.

Moreover when calculating number of root clusters we should be using
macro EXT4_NUM_B2C() instead of EXT4_B2C() otherwise the result might be
off by one. However r_blocks_count should always be a multiple of the
cluster ratio so doing a plain bit shift should be enough here. We
avoid using EXT4_B2C() because it's confusing.

As a result of the first problem number of free clusters is much bigger
than it should have been and ext4_has_free_clusters() would return 1 even
if there is really not enough free clusters available.

Fix this by removing the EXT4_C2B() conversion of free clusters and
using bit shift when calculating number of root clusters. This bug
affects number of xfstests tests covering file system ENOSPC situation
handling. With this patch most of the ENOSPC problems with bigalloc file
system disappear, especially the errors caused by delayed allocation not
having enough space when the actual allocation is finally requested.

Signed-off-by: Lukas Czerner <lczerner@redhat.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Cc: stable@vger.kernel.org
2013-02-22 15:27:52 -05:00
Eryu Guan
d438147211 ext4: no need to remove extent if len is 0 in ext4_es_remove_extent()
len is 0 means no extent needs to be removed, so return immediately.
Otherwise it could trigger the following BUG_ON() in
ext4_es_remove_extent()

	end = lblk + len - 1;
	BUG_ON(end < lblk);

This could be reproduced by a simple truncate(1) command by an
unprivileged user

	truncate -s $(($((2**32 - 1)) * 4096)) /mnt/ext4/testfile

The same is true for __es_insert_extent().

Patched kernel passed xfstests regression test.

Signed-off-by: Eryu Guan <guaneryu@gmail.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Reviewed-by: Zheng Liu <wenqing.lz@taobao.com>
2013-02-22 15:27:47 -05:00
Darrick J. Wong
1d1d1a7672 mm: only enforce stable page writes if the backing device requires it
Create a helper function to check if a backing device requires stable
page writes and, if so, performs the necessary wait.  Then, make it so
that all points in the memory manager that handle making pages writable
use the helper function.  This should provide stable page write support
to most filesystems, while eliminating unnecessary waiting for devices
that don't require the feature.

Before this patchset, all filesystems would block, regardless of whether
or not it was necessary.  ext3 would wait, but still generate occasional
checksum errors.  The network filesystems were left to do their own
thing, so they'd wait too.

After this patchset, all the disk filesystems except ext3 and btrfs will
wait only if the hardware requires it.  ext3 (if necessary) snapshots
pages instead of blocking, and btrfs provides its own bdi so the mm will
never wait.  Network filesystems haven't been touched, so either they
provide their own stable page guarantees or they don't block at all.
The blocking behavior is back to what it was before 3.0 if you don't
have a disk requiring stable page writes.

Here's the result of using dbench to test latency on ext2:

3.8.0-rc3:
 Operation      Count    AvgLat    MaxLat
 ----------------------------------------
 WriteX        109347     0.028    59.817
 ReadX         347180     0.004     3.391
 Flush          15514    29.828   287.283

Throughput 57.429 MB/sec  4 clients  4 procs  max_latency=287.290 ms

3.8.0-rc3 + patches:
 WriteX        105556     0.029     4.273
 ReadX         335004     0.005     4.112
 Flush          14982    30.540   298.634

Throughput 55.4496 MB/sec  4 clients  4 procs  max_latency=298.650 ms

As you can see, the maximum write latency drops considerably with this
patch enabled.  The other filesystems (ext3/ext4/xfs/btrfs) behave
similarly, but see the cover letter for those results.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Acked-by: Steven Whitehouse <swhiteho@redhat.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Artem Bityutskiy <dedekind1@gmail.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Mark Fasheh <mfasheh@suse.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Eric Van Hensbergen <ericvh@gmail.com>
Cc: Ron Minnich <rminnich@sandia.gov>
Cc: Latchesar Ionkov <lucho@ionkov.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-02-21 17:22:19 -08:00
Lukas Czerner
1231b3a1eb ext4: fix xattr block allocation/release with bigalloc
Currently when new xattr block is created or released we we would call
dquot_free_block() or dquot_alloc_block() respectively, among the else
decrementing or incrementing the number of blocks assigned to the
inode by one block.

This however does not work for bigalloc file system because we always
allocate/free the whole cluster so we have to count with that in
dquot_free_block() and dquot_alloc_block() as well.

Use the clusters-to-blocks conversion EXT4_C2B() when passing number of
blocks to the dquot_alloc/free functions to fix the problem.

The problem has been revealed by xfstests #117 (and possibly others).

Signed-off-by: Lukas Czerner <lczerner@redhat.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Reviewed-by: Eric Sandeen <sandeen@redhat.com>
Cc: stable@vger.kernel.org
2013-02-18 12:12:07 -05:00
Zheng Liu
74cd15cd02 ext4: reclaim extents from extent status tree
Although extent status is loaded on-demand, we also need to reclaim
extent from the tree when we are under a heavy memory pressure because
in some cases fragmented extent tree causes status tree costs too much
memory.

Here we maintain a lru list in super_block.  When the extent status of
an inode is accessed and changed, this inode will be move to the tail
of the list.  The inode will be dropped from this list when it is
cleared.  In the inode, a counter is added to count the number of
cached objects in extent status tree.  Here only written/unwritten/hole
extent is counted because delayed extent doesn't be reclaimed due to
fiemap, bigalloc and seek_data/hole need it.  The counter will be
increased as a new extent is allocated, and it will be decreased as a
extent is freed.

In this commit we use normal shrinker framework to reclaim memory from
the status tree.  ext4_es_reclaim_extents_count() traverses the lru list
to count the number of reclaimable extents.  ext4_es_shrink() tries to
reclaim written/unwritten/hole extents from extent status tree.  The
inode that has been shrunk is moved to the tail of lru list.

Signed-off-by: Zheng Liu <wenqing.lz@taobao.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Cc: Jan kara <jack@suse.cz>
2013-02-18 00:32:55 -05:00
Zheng Liu
bdedbb7b8d ext4: adjust some functions for reclaiming extents from extent status tree
This commit changes some interfaces in extent status tree because we
need to use inode to count the cached objects in a extent status tree.

Signed-off-by: Zheng Liu <wenqing.lz@taobao.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Cc: Jan kara <jack@suse.cz>
2013-02-18 00:32:02 -05:00
Zheng Liu
69eb33dc24 ext4: remove single extent cache
Single extent cache could be removed because we have extent status tree
as a extent cache, and it would be better.

Signed-off-by: Zheng Liu <wenqing.lz@taobao.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Cc: Jan kara <jack@suse.cz>
2013-02-18 00:31:07 -05:00
Zheng Liu
d100eef244 ext4: lookup block mapping in extent status tree
After tracking all extent status, we already have a extent cache in
memory.  Every time we want to lookup a block mapping, we can first
try to lookup it in extent status tree to avoid a potential disk I/O.

A new function called ext4_es_lookup_extent is defined to finish this
work.  When we try to lookup a block mapping, we always call
ext4_map_blocks and/or ext4_da_map_blocks.  So in these functions we
first try to lookup a block mapping in extent status tree.

A new flag EXT4_GET_BLOCKS_NO_PUT_HOLE is used in ext4_da_map_blocks
in order not to put a hole into extent status tree because this hole
will be converted to delayed extent in the tree immediately.

Signed-off-by: Zheng Liu <wenqing.lz@taobao.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Cc: Jan kara <jack@suse.cz>
2013-02-18 00:29:59 -05:00
Zheng Liu
f7fec032aa ext4: track all extent status in extent status tree
By recording the phycisal block and status, extent status tree is able
to track the status of every extents.  When we call _map_blocks
functions to lookup an extent or create a new written/unwritten/delayed
extent, this extent will be inserted into extent status tree.

We don't load all extents from disk in alloc_inode() because it costs
too much memory, and if a file is opened and closed frequently it will
takes too much time to load all extent information.  So currently when
we create/lookup an extent, this extent will be inserted into extent
status tree.  Hence, the extent status tree may not comprehensively
contain all of the extents found in the file.

Here a condition we need to take care is that an extent might contains
unwritten and delayed status simultaneously because an extent is delayed
allocated and could be allocated by fallocate.  At this time we need to
keep delayed status because later we need to update delayed reservation
space using it.

Signed-off-by: Zheng Liu <wenqing.lz@taobao.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Cc: Jan kara <jack@suse.cz>
2013-02-18 00:28:47 -05:00
Zheng Liu
a25a4e1a5d ext4: let ext4_ext_map_blocks return EXT4_MAP_UNWRITTEN flag
This commit lets ext4_ext_map_blocks return EXT4_MAP_UNWRITTEN flag
because in later commit ext4_map_blocks needs to use this flag to
determine the extent status.

Signed-off-by: Zheng Liu <wenqing.lz@taobao.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Reviewed-by: Jan Kara <jack@suse.cz>
2013-02-18 00:28:04 -05:00
Zheng Liu
be401363ac ext4: rename and improbe ext4_es_find_extent()
This commit renames ext4_es_find_extent with ext4_es_find_delayed_extent
and improve this function.  First, we split input and output parameter.
Second, this function never return the first block of the next delayed
extent after 'es'.

Signed-off-by: Zheng Liu <wenqing.lz@taobao.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Cc: Jan kara <jack@suse.cz>
2013-02-18 00:27:26 -05:00
Zheng Liu
fdc0212e86 ext4: add physical block and status member into extent status tree
This commit adds two members in extent_status structure to let it record
physical block and extent status.  Here es_pblk is used to record both
of them because physical block only has 48 bits.  So extent status could
be stashed into it so that we can save some memory.  Now written,
unwritten, delayed and hole are defined as status.

Due to new member is added into extent status tree, all interfaces need
to be adjusted.

Signed-off-by: Zheng Liu <wenqing.lz@taobao.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Reviewed-by: Jan Kara <jack@suse.cz>
2013-02-18 00:26:51 -05:00
Zheng Liu
06b0c88621 ext4: refine extent status tree
This commit refines the extent status tree code.

1) A prefix 'es_' is added to to the extent status tree structure
members.

2) Refactored es_remove_extent() so that __es_remove_extent() can be
used by es_insert_extent() to remove the old extent entry(-ies) before
inserting a new one.

3) Rename extent_status_end() to ext4_es_end()

4) ext4_es_can_be_merged() is define to check whether two extents can
be merged or not.

5) Update and clarified comments.

Signed-off-by: Zheng Liu <wenqing.lz@taobao.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Reviewed-by: Jan Kara <jack@suse.cz>
2013-02-18 00:26:51 -05:00
Theodore Ts'o
0f70b40613 ext4: use ERR_PTR() abstraction for ext4_append()
Use ERR_PTR()/IS_ERR() abstraction instead of passing in a separate
pointer to an integer for the error code, as a code cleanup.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2013-02-15 03:35:57 -05:00
Theodore Ts'o
dc6982ff4d ext4: refactor code to read directory blocks into ext4_read_dirblock()
The code to read in directory blocks and verify their metadata
checksums was replicated in ten different places across
fs/ext4/namei.c, and the code was buggy in subtle ways in a number of
those replicated sites.  In some cases, ext4_error() was called with a
training newline.  In others, in particularly in empty_dir(), it was
possible to call ext4_dirent_csum_verify() on an index block, which
would trigger false warnings requesting the system adminsitrator to
run e2fsck.

By refactoring the code, we make the code more readable, as well as
shrinking the compiled object file by over 700 bytes and 50 lines of
code.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2013-02-14 23:59:26 -05:00
Theodore Ts'o
01a523eb51 ext4: add debugging context for warning in ext4_da_update_reserve_space()
Print some additional debugging context to hopefully help to debug a
warning which is getting triggered by xfstests #74.

Also remove extraneous newlines from when printk's were converted to
ext4_warning() and ext4_msg().

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2013-02-14 15:51:58 -05:00
Theodore Ts'o
8de5c325b4 ext4: use KERN_WARNING for warning messages
Some messages printed related to a WARN_ON(1) were printed using
KERN_NOTICE.  Use KERN_WARNING or ext4_warning() instead so that
context related to the WARN_ON() is printed at the same printk warning
level (and log files, etc.)

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2013-02-14 15:11:41 -05:00
Theodore Ts'o
a0b30c1229 ext4: use module parameters instead of debugfs for mballoc_debug
There are multiple reasons to move away from debugfs.  First of all,
we are only using it for a single parameter, and it is much more
complicated to set up (some 30 lines of code compared to 3), and one
more thing that might fail while loading the ext4 module.

Secondly, as a module paramter it can be specified as a boot option if
ext4 is built into the kernel, or as a parameter when the module is
loaded, and it can also be manipulated dynamically under
/sys/module/ext4/parameters/mballoc_debug.  So it is more flexible.

Ultimately we want to move away from using mb_debug() towards
tracepoints, but for now this is still a useful simplification of the
code base.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2013-02-09 16:28:20 -05:00
Theodore Ts'o
1139575a92 ext4: start handle at the last possible moment when creating inodes
In ext4_{create,mknod,mkdir,symlink}(), don't start the journal handle
until the inode has been succesfully allocated.  In order to do this,
we need to start the handle in the ext4_new_inode().  So create a new
variant of this function, ext4_new_inode_start_handle(), so the handle
can be created at the last possible minute, before we need to modify
the inode allocation bitmap block.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2013-02-09 16:27:09 -05:00
Theodore Ts'o
95eaefbdec ext4: fix the number of credits needed for acl ops with inline data
Operations which modify extended attributes may need extra journal
credits if inline data is used, since there is a chance that some
extended attributes may need to get pushed to an external attribute
block.

Changes to reflect this was made in xattr.c, but they were missed in
fs/ext4/acl.c.  To fix this, abstract the calculation of the number of
credits needed for xattr operations to an inline function defined in
ext4_jbd2.h, and use it in acl.c and xattr.c.

Also move the function declarations used in inline.c from xattr.h
(where they are non-obviously hidden, and caused problems since
ext4_jbd2.h needs to use the function ext4_has_inline_data), and move
them to ext4.h.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Reviewed-by: Tao Ma <boyu.mt@taobao.com>
Reviewed-by: Jan Kara <jack@suse.cz>
2013-02-09 15:23:03 -05:00
Theodore Ts'o
64044abf05 ext4: fix the number of credits needed for ext4_unlink() and ext4_rmdir()
The ext4_unlink() and ext4_rmdir() don't actually release the blocks
associated with the file/directory.  This gets done in a separate jbd2
handle called via ext4_evict_inode().  Thus, we don't need to reserve
lots of journal credits for the truncate.

Note that using too many journal credits is non-optimal because it can
leading to the journal transmit getting closed too early, before it is
strictly necessary.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Reviewed-by: Jan Kara <jack@suse.cz>
2013-02-09 15:06:24 -05:00
Theodore Ts'o
4b217630d0 ext4: fix the number of credits needed for ext4_ext_migrate()
The migration ioctl creates a temporary inode.  Since this inode is
never linked to a directory, we don't need to reserve journal credits
required for modifying the directory.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Reviewed-by: Jan Kara <jack@suse.cz>
2013-02-09 12:50:27 -05:00
Theodore Ts'o
8dcfaad244 ext4: start handle at the last possible moment in ext4_rmdir()
Don't start the jbd2 transaction handle until after the directory
entry has been found, to minimize the amount of time that a handle is
held active.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Reviewed-by: Jan Kara <jack@suse.cz>
2013-02-09 09:45:11 -05:00
Theodore Ts'o
931b68649d ext4: start handle at the last possible moment in ext4_unlink()
Don't start the jbd2 transaction handle until after the directory
entry has been found, to minimize the amount of time that a handle is
held active.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Reviewed-by: Jan Kara <jack@suse.cz>
2013-02-09 09:43:39 -05:00
Theodore Ts'o
47564bfb95 ext4: grab page before starting transaction handle in write_begin()
The grab_cache_page_write_begin() function can potentially sleep for a
long time, since it may need to do memory allocation which can block
if the system is under significant memory pressure, and because it may
be blocked on page writeback.  If it does take a long time to grab the
page, it's better that we not hold an active jbd2 handle.

So grab a handle on the page first, and _then_ start the transaction
handle.

This commit fixes the following long transaction handle hold time:

postmark-2917  [000] ....   196.435786: jbd2_handle_stats: dev 254,32
   tid 570 type 2 line_no 2541 interval 311 sync 0 requested_blocks 1
   dirtied_blocks 0

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Reviewed-by: Jan Kara <jack@suse.cz>
2013-02-09 09:24:14 -05:00
Theodore Ts'o
9924a92a8c ext4: pass context information to jbd2__journal_start()
So we can better understand what bits of ext4 are responsible for
long-running jbd2 handles, use jbd2__journal_start() so we can pass
context information for logging purposes.

The recommended way for finding the longer-running handles is:

   T=/sys/kernel/debug/tracing
   EVENT=$T/events/jbd2/jbd2_handle_stats
   echo "interval > 5" > $EVENT/filter
   echo 1 > $EVENT/enable

   ./run-my-fs-benchmark

   cat $T/trace > /tmp/problem-handles

This will list handles that were active for longer than 20ms.  Having
longer-running handles is bad, because a commit started at the wrong
time could stall for those 20+ milliseconds, which could delay an
fsync() or an O_SYNC operation.  Here is an example line from the
trace file describing a handle which lived on for 311 jiffies, or over
1.2 seconds:

postmark-2917  [000] ....   196.435786: jbd2_handle_stats: dev 254,32 
   tid 570 type 2 line_no 2541 interval 311 sync 0 requested_blocks 1
   dirtied_blocks 0

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2013-02-08 21:59:22 -05:00
Theodore Ts'o
722887ddc8 ext4: move the jbd2 wrapper functions out of super.c
Move the jbd2 wrapper functions which start and stop handles out of
super.c, where they don't really logically belong, and into
ext4_jbd2.c.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2013-02-08 13:00:31 -05:00
Theodore Ts'o
40ae348762 ext4: optimize mballoc for large allocations
The ext4 block allocator only maintains buddy bitmaps for chunks which
are less than or equal to one quarter of a block group.  That is, for
a file aystem with a 1k blocksize, and where the number of blocks in a
block group is 8192 blocks, the largest chunk size tracked by buddy
bitmaps is 2048 blocks.

For a file system with a 4k blocksize, and where the number of blocks
in a block group is 32768 blocks, the largest chunk size tracked by
buddy bitmaps is 8192 blocks.

To work around this code, mballoc.c before this commit would truncate
allocation requests to the number of blocks in a block group minus 10.
Why 10?  Aside from being a completely arbitrary number, it avoids
block allocation to be a power of two larger than 25% of the block
group.  If you try to explicitly fallocate 50% of the block group
size, this will demonstrate the problem; the block allocation code
will scan the all of the blocks in the file system with cr==0 (since
the request is for a natural power of two), but then completely fail
for all blocks groups, since the buddy bitmaps don't track chunk sizes
of 50% of the block group.

To fix this, in these we use ext4_mb_complex_scan_group() instead of
ext4_mb_simple_scan_group().

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Cc: Andreas Dilger <adilger@dilger.ca>
2013-02-04 15:08:40 -05:00
Theodore Ts'o
8dc0aa8cf0 ext4: check incompatible mount options while mounting ext2/3
Check for incompatible mount options when using the ext4 file system
driver to mount ext2 or ext3 file systems.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2013-02-02 23:38:39 -05:00
Jan Kara
e33e60eaed ext4: print error when argument of inode_readahead_blk is invalid
If argument of inode_readahead_blk is too big, we just bail out
without printing any error. Fix this since it could confuse users.

Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2013-02-02 23:14:31 -05:00
Jan Kara
5f3633e36b ext4: make mount option parsing loop more logical
The loop looking for correct mount option entry is more logical if it is
written rewritten as an empty loop looking for correct option entry and then
code handling the option. It also saves one level of indentation for a lot of
code so we can join a couple of split lines.

Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2013-02-02 23:09:36 -05:00
Jan Kara
0efb3b2300 ext4: move several mount options to standard handling loop
Several mount option (resuid, resgid, journal_dev, journal_ioprio) are
currently handled before we enter standard option handling loop. I don't
see a reason for this so move them to normal handling loop to make things
more regular.

Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2013-02-02 22:52:19 -05:00
Cong Ding
0e79537d30 ext4: reduce one "if" comparison in ext4_dirhash()
It is unnecessary to check i<4 after the loop; just do it before the
break.

Signed-off-by: Cong Ding <dinggnu@gmail.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2013-02-01 22:33:21 -05:00
Niu Yawei
f116700971 ext4: fix race in ext4_mb_add_n_trim()
In ext4_mb_add_n_trim(), lg_prealloc_lock should be taken when
changing the lg_prealloc_list.

Signed-off-by: Niu Yawei <yawei.niu@intel.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Cc: stable@vger.kernel.org
2013-02-01 21:31:27 -05:00
Akria Fujita
87e698734b ext4: fix smatch warning in move_extent.c's mext_replace_branches()
Commit 2147b1a6a4 resulted in a new smatch warning:

> fs/ext4/move_extent.c:693 mext_replace_branches()
> 	 warn: variable dereferenced before check 'dext' (see line 683)

Fix this by adding a check to make sure dext is non-NULL before we
derefrence it.

Signed-off-by: Akria Fujita <a-fujita@rs.jp.nec.com>
[ modified by tytso to make sure an ext4_error is called ]
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2013-02-01 20:52:46 -05:00
Julia Lawall
524c19ebc9 ext4: use WARN in ext4_alloc_blocks
Use WARN rather than printk followed by WARN_ON(1), for conciseness.

A simplified version of the semantic patch that makes this transformation
is as follows: (http://coccinelle.lip6.fr/)

// <smpl>
@@
expression list es;
@@

-printk(
+WARN(1,
  es);
-WARN_ON(1);
// </smpl>

Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2013-02-01 20:07:21 -05:00
Jan Kara
091e26dfc1 ext4: fix possible use-after-free with AIO
Running AIO is pinning inode in memory using file reference. Once AIO
is completed using aio_complete(), file reference is put and inode can
be freed from memory. So we have to be sure that calling aio_complete()
is the last thing we do with the inode.

CC: stable@vger.kernel.org
Reviewed-by: Carlos Maiolino <cmaiolino@redhat.com>
Acked-by: Jeff Moyer <jmoyer@redhat.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2013-01-29 22:48:17 -05:00
Guo Chao
b1deefc99e ext4: remove unnecessary NULL pointer check
brelse() and ext4_journal_force_commit() are both inlined and able
to handle NULL.

Signed-off-by: Guo Chao <yan@linux.vnet.ibm.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2013-01-28 21:41:02 -05:00
Guo Chao
41be871f74 ext4: remove useless assignment in dx_probe()
Signed-off-by: Guo Chao <yan@linux.vnet.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2013-01-28 21:33:28 -05:00
Guo Chao
2bbbee2a68 ext4: remove unused variable in add_dirent_to_buf()
After commit 978fef9 (create __ext4_insert_dentry for dir entry
insertion), 'reclen' is not used anymore.

Signed-off-by: Guo Chao <yan@linux.vnet.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
2013-01-28 21:26:44 -05:00
Guo Chao
d5ac777305 ext4: release buffer when checksum failed
Commit b0336e8d (ext4: calculate and verify checksums of directory
leaf blocks) and commit dbe89444 (ext4: Calculate and verify checksums
for htree nodes) forget to release buffer when checksum failed, at
some places.

Signed-off-by: Guo Chao <yan@linux.vnet.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
2013-01-28 21:23:24 -05:00
Lukas Czerner
b06acd38a4 ext4: remove explicit WARN_ON when ext4_map_blocks() fails
In two places we call WARN_ON() before we print out the debug message,
however we agreed that the WARN_ON() is unnecessary at those places so
remove them.

Also use ext4_warning() instead of ext4_msg() and printk().

Signed-off-by: Lukas Czerner <lczerner@redhat.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2013-01-28 21:21:12 -05:00
Lukas Czerner
cfa7275482 ext4: remove unused variable flags
Remove unused variable flags from dump_completed_IO(). The code is
only exercised when EXT4FS_DEBUG is defined.

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>
2013-01-28 21:14:11 -05:00
Jan Kara
fe386132f6 ext4: fix ext4_writepage() to achieve data=ordered guarantees
So far ext4_writepage() skipped writing pages that had any delayed or
unwritten buffers attached. When blocksize < pagesize this breaks
data=ordered mode guarantees as we can have a page with one freshly
allocated buffer whose allocation is part of the committing
transaction and another buffer in the page which is delayed or
unwritten. So fix this problem by calling ext4_bio_writepage()
anyway. It will submit mapped buffers and leave others alone.

Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2013-01-28 21:06:42 -05:00
Jan Kara
8a850c3fb8 ext4: Make ext4_bio_writepage() handle unprepared buffers
So far ext4_bio_writepage() unconditionally cleared dirty bit on all
buffers underlying the page. That implicitely assumes we can write all
buffers. So far that is true because callers call into
ext4_bio_writepage() make sure all buffers in the page are mapped but:

a) it's a data corruption bug waiting to happen
b) in data=ordered mode when blocksize < pagesize we do need to write
   pages that may have only some of dirty buffers mapped.

So change ext4_bio_writepage() to skip buffers that cannot be written without
clearing their dirty bit.

Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2013-01-28 20:53:28 -05:00
Jan Kara
b6a8e62f8b ext4: simplify mpage_add_bh_to_extent()
The argument b_size of mpage_add_bh_to_extent() was bogus since it was
always == blocksize (which we can easily derive from inode->i_blkbits).
Also second branch of condition:
	if (nrblocks >= EXT4_MAX_TRANS_DATA) {
	} else if ((nrblocks + (b_size >> mpd->inode->i_blkbits)) >
						EXT4_MAX_TRANS_DATA) {
	}
was never taken because (b_size >> mpd->inode->i_blkbits) == 1.

Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2013-01-28 13:06:48 -05:00