Commit Graph

353 Commits

Author SHA1 Message Date
Nicolai Stange 935244cd54 ext4: silence UBSAN in ext4_mb_init()
Currently, in ext4_mb_init(), there's a loop like the following:

  do {
    ...
    offset += 1 << (sb->s_blocksize_bits - i);
    i++;
  } while (i <= sb->s_blocksize_bits + 1);

Note that the updated offset is used in the loop's next iteration only.

However, at the last iteration, that is at i == sb->s_blocksize_bits + 1,
the shift count becomes equal to (unsigned)-1 > 31 (c.f. C99 6.5.7(3))
and UBSAN reports

  UBSAN: Undefined behaviour in fs/ext4/mballoc.c:2621:15
  shift exponent 4294967295 is too large for 32-bit type 'int'
  [...]
  Call Trace:
   [<ffffffff818c4d25>] dump_stack+0xbc/0x117
   [<ffffffff818c4c69>] ? _atomic_dec_and_lock+0x169/0x169
   [<ffffffff819411ab>] ubsan_epilogue+0xd/0x4e
   [<ffffffff81941cac>] __ubsan_handle_shift_out_of_bounds+0x1fb/0x254
   [<ffffffff81941ab1>] ? __ubsan_handle_load_invalid_value+0x158/0x158
   [<ffffffff814b6dc1>] ? kmem_cache_alloc+0x101/0x390
   [<ffffffff816fc13b>] ? ext4_mb_init+0x13b/0xfd0
   [<ffffffff814293c7>] ? create_cache+0x57/0x1f0
   [<ffffffff8142948a>] ? create_cache+0x11a/0x1f0
   [<ffffffff821c2168>] ? mutex_lock+0x38/0x60
   [<ffffffff821c23ab>] ? mutex_unlock+0x1b/0x50
   [<ffffffff814c26ab>] ? put_online_mems+0x5b/0xc0
   [<ffffffff81429677>] ? kmem_cache_create+0x117/0x2c0
   [<ffffffff816fcc49>] ext4_mb_init+0xc49/0xfd0
   [...]

Observe that the mentioned shift exponent, 4294967295, equals (unsigned)-1.

Unless compilers start to do some fancy transformations (which at least
GCC 6.0.0 doesn't currently do), the issue is of cosmetic nature only: the
such calculated value of offset is never used again.

Silence UBSAN by introducing another variable, offset_incr, holding the
next increment to apply to offset and adjust that one by right shifting it
by one position per loop iteration.

Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=114701
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=112161

Cc: stable@vger.kernel.org
Signed-off-by: Nicolai Stange <nicstange@gmail.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2016-05-05 19:46:19 -04:00
Nicolai Stange b5cb316cdf ext4: address UBSAN warning in mb_find_order_for_block()
Currently, in mb_find_order_for_block(), there's a loop like the following:

  while (order <= e4b->bd_blkbits + 1) {
    ...
    bb += 1 << (e4b->bd_blkbits - order);
  }

Note that the updated bb is used in the loop's next iteration only.

However, at the last iteration, that is at order == e4b->bd_blkbits + 1,
the shift count becomes negative (c.f. C99 6.5.7(3)) and UBSAN reports

  UBSAN: Undefined behaviour in fs/ext4/mballoc.c:1281:11
  shift exponent -1 is negative
  [...]
  Call Trace:
   [<ffffffff818c4d35>] dump_stack+0xbc/0x117
   [<ffffffff818c4c79>] ? _atomic_dec_and_lock+0x169/0x169
   [<ffffffff819411bb>] ubsan_epilogue+0xd/0x4e
   [<ffffffff81941cbc>] __ubsan_handle_shift_out_of_bounds+0x1fb/0x254
   [<ffffffff81941ac1>] ? __ubsan_handle_load_invalid_value+0x158/0x158
   [<ffffffff816e93a0>] ? ext4_mb_generate_from_pa+0x590/0x590
   [<ffffffff816502c8>] ? ext4_read_block_bitmap_nowait+0x598/0xe80
   [<ffffffff816e7b7e>] mb_find_order_for_block+0x1ce/0x240
   [...]

Unless compilers start to do some fancy transformations (which at least
GCC 6.0.0 doesn't currently do), the issue is of cosmetic nature only: the
such calculated value of bb is never used again.

Silence UBSAN by introducing another variable, bb_incr, holding the next
increment to apply to bb and adjust that one by right shifting it by one
position per loop iteration.

Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=114701
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=112161

Cc: stable@vger.kernel.org
Signed-off-by: Nicolai Stange <nicstange@gmail.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2016-05-05 17:38:03 -04:00
Jakub Wilk 8d2ae1cbe8 ext4: remove trailing \n from ext4_warning/ext4_error calls
Messages passed to ext4_warning() or ext4_error() don't need trailing
newlines, because these function add the newlines themselves.

Signed-off-by: Jakub Wilk <jwilk@jwilk.net>
2016-04-27 01:11:21 -04:00
Kirill A. Shutemov ea1754a084 mm, fs: remove remaining PAGE_CACHE_* and page_cache_{get,release} usage
Mostly direct substitution with occasional adjustment or removing
outdated comments.

Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-04-04 10:41:08 -07:00
Kirill A. Shutemov 09cbfeaf1a mm, fs: get rid of PAGE_CACHE_* and page_cache_{get,release} macros
PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} macros were introduced *long* time
ago with promise that one day it will be possible to implement page
cache with bigger chunks than PAGE_SIZE.

This promise never materialized.  And unlikely will.

We have many places where PAGE_CACHE_SIZE assumed to be equal to
PAGE_SIZE.  And it's constant source of confusion on whether
PAGE_CACHE_* or PAGE_* constant should be used in a particular case,
especially on the border between fs and mm.

Global switching to PAGE_CACHE_SIZE != PAGE_SIZE would cause to much
breakage to be doable.

Let's stop pretending that pages in page cache are special.  They are
not.

The changes are pretty straight-forward:

 - <foo> << (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> <foo>;

 - <foo> >> (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> <foo>;

 - PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} -> PAGE_{SIZE,SHIFT,MASK,ALIGN};

 - page_cache_get() -> get_page();

 - page_cache_release() -> put_page();

This patch contains automated changes generated with coccinelle using
script below.  For some reason, coccinelle doesn't patch header files.
I've called spatch for them manually.

The only adjustment after coccinelle is revert of changes to
PAGE_CAHCE_ALIGN definition: we are going to drop it later.

There are few places in the code where coccinelle didn't reach.  I'll
fix them manually in a separate patch.  Comments and documentation also
will be addressed with the separate patch.

virtual patch

@@
expression E;
@@
- E << (PAGE_CACHE_SHIFT - PAGE_SHIFT)
+ E

@@
expression E;
@@
- E >> (PAGE_CACHE_SHIFT - PAGE_SHIFT)
+ E

@@
@@
- PAGE_CACHE_SHIFT
+ PAGE_SHIFT

@@
@@
- PAGE_CACHE_SIZE
+ PAGE_SIZE

@@
@@
- PAGE_CACHE_MASK
+ PAGE_MASK

@@
expression E;
@@
- PAGE_CACHE_ALIGN(E)
+ PAGE_ALIGN(E)

@@
expression E;
@@
- page_cache_get(E)
+ get_page(E)

@@
expression E;
@@
- page_cache_release(E)
+ put_page(E)

Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-04-04 10:41:08 -07:00
Konstantin Khlebnikov adb7ef600c ext4: use __GFP_NOFAIL in ext4_free_blocks()
This might be unexpected but pages allocated for sbi->s_buddy_cache are
charged to current memory cgroup. So, GFP_NOFS allocation could fail if
current task has been killed by OOM or if current memory cgroup has no
free memory left. Block allocator cannot handle such failures here yet.

Signed-off-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2016-03-13 17:29:06 -04:00
Adam Buchbinder b8a07463c8 ext4: fix misspellings in comments.
Signed-off-by: Adam Buchbinder <adam.buchbinder@gmail.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2016-03-09 23:49:05 -05:00
Daeho Jeong f96c450dab ext4: make sure to revoke all the freeable blocks in ext4_free_blocks
Now, ext4_free_blocks() doesn't revoke data blocks of per-file data
journalled inode and it can cause file data inconsistency problems.
Even though data blocks of per-file data journalled inode are already
forgotten by jbd2_journal_invalidatepage() in advance of invoking
ext4_free_blocks(), we still need to revoke the data blocks here.
Moreover some of the metadata blocks, which are not found by
sb_find_get_block(), are still needed to be revoked, but this is also
missing here.

Signed-off-by: Daeho Jeong <daeho.jeong@samsung.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Jan Kara <jack@suse.cz>
2016-02-21 18:31:41 -05:00
Huaitong Han 802cf1f9f5 ext4: add a line break for proc mb_groups display
This patch adds a line break for proc mb_groups display.

Signed-off-by: Huaitong Han <huaitong.han@intel.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Andreas Dilger <adilger@dilger.ca>
2016-02-12 00:17:16 -05:00
Andrew Morton 79211c8ed1 remove abs64()
Switch everything to the new and more capable implementation of abs().
Mainly to give the new abs() a bit of a workout.

Cc: Michal Nazarewicz <mina86@mina86.com>
Cc: John Stultz <john.stultz@linaro.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-11-09 15:11:24 -08:00
John Stultz 16175039e6 ext4: fix abs() usage in ext4_mb_check_group_pa
The ext4_fsblk_t type is a long long, which should not be used
with abs(), as is done in ext4_mb_check_group_pa().

This patch modifies ext4_mb_check_group_pa() to use abs64()
instead.

Signed-off-by: John Stultz <john.stultz@linaro.org>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2015-10-19 00:01:05 -04:00
Daeho Jeong 9c02ac9798 ext4: fix xfstest generic/269 double revoked buffer bug with bigalloc
When you repeatly execute xfstest generic/269 with bigalloc_1k option
enabled using the below command:

"./kvm-xfstests -c bigalloc_1k -m nodelalloc -C 1000 generic/269"

you can easily see the below bug message.

"JBD2 unexpected failure: jbd2_journal_revoke: !buffer_revoked(bh);"

This means that an already revoked buffer is erroneously revoked again
and it is caused by doing revoke for the buffer at the wrong position
in ext4_free_blocks(). We need to re-position the buffer revoke
procedure for an unspecified buffer after checking the cluster boundary
for bigalloc option. If not, some part of the cluster can be doubly
revoked.

Signed-off-by: Daeho Jeong <daeho.jeong@samsung.com>
2015-10-17 22:28:21 -04:00
Darrick J. Wong 9008a58e5d ext4: make the bitmap read routines return real error codes
Make the bitmap reaading routines return real error codes (EIO,
EFSCORRUPTED, EFSBADCRC) which can then be reflected back to
userspace for more precise diagnosis work.

In particular, this means that mballoc no longer claims that we're out
of memory if the block bitmaps become corrupt.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2015-10-17 21:33:24 -04:00
Theodore Ts'o ebd173beb8 ext4: move procfs registration code to fs/ext4/sysfs.c
This allows us to refactor the procfs code, which saves a bit of
compiled space.  More importantly it isolates most of the procfs
support code into a single file, so it's easier to #ifdef it out if
the proc file system has been disabled.

Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2015-09-23 12:46:17 -04:00
Linus Torvalds 1c4c7159ed Bug fixes (all for stable kernels) for ext4:
* address corner cases for indirect blocks->extent migration
   * fix reserved block accounting invalidate_page when
 	page_size != block_size (i.e., ppc or 1k block size file systems)
   * fix deadlocks when a memcg is under heavy memory pressure
   * fix fencepost error in lazytime optimization
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Merge tag 'ext4_for_linus_stable' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4

Pull ext4 bugfixes from Ted Ts'o:
 "Bug fixes (all for stable kernels) for ext4:

   - address corner cases for indirect blocks->extent migration

   - fix reserved block accounting invalidate_page when
     page_size != block_size (i.e., ppc or 1k block size file systems)

   - fix deadlocks when a memcg is under heavy memory pressure

   - fix fencepost error in lazytime optimization"

* tag 'ext4_for_linus_stable' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4:
  ext4: replace open coded nofail allocation in ext4_free_blocks()
  ext4: correctly migrate a file with a hole at the beginning
  ext4: be more strict when migrating to non-extent based file
  ext4: fix reservation release on invalidatepage for delalloc fs
  ext4: avoid deadlocks in the writeback path by using sb_getblk_gfp
  bufferhead: Add _gfp version for sb_getblk()
  ext4: fix fencepost error in lazytime optimization
2015-07-05 16:24:54 -07:00
Michal Hocko 7444a072c3 ext4: replace open coded nofail allocation in ext4_free_blocks()
ext4_free_blocks is looping around the allocation request and mimics
__GFP_NOFAIL behavior without any allocation fallback strategy. Let's
remove the open coded loop and replace it with __GFP_NOFAIL. Without the
flag the allocator has no way to find out never-fail requirement and
cannot help in any way.

Signed-off-by: Michal Hocko <mhocko@suse.cz>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@vger.kernel.org
2015-07-05 12:33:44 -04:00
Linus Torvalds e4bc13adfd Merge branch 'for-4.2/writeback' of git://git.kernel.dk/linux-block
Pull cgroup writeback support from Jens Axboe:
 "This is the big pull request for adding cgroup writeback support.

  This code has been in development for a long time, and it has been
  simmering in for-next for a good chunk of this cycle too.  This is one
  of those problems that has been talked about for at least half a
  decade, finally there's a solution and code to go with it.

  Also see last weeks writeup on LWN:

        http://lwn.net/Articles/648292/"

* 'for-4.2/writeback' of git://git.kernel.dk/linux-block: (85 commits)
  writeback, blkio: add documentation for cgroup writeback support
  vfs, writeback: replace FS_CGROUP_WRITEBACK with SB_I_CGROUPWB
  writeback: do foreign inode detection iff cgroup writeback is enabled
  v9fs: fix error handling in v9fs_session_init()
  bdi: fix wrong error return value in cgwb_create()
  buffer: remove unusued 'ret' variable
  writeback: disassociate inodes from dying bdi_writebacks
  writeback: implement foreign cgroup inode bdi_writeback switching
  writeback: add lockdep annotation to inode_to_wb()
  writeback: use unlocked_inode_to_wb transaction in inode_congested()
  writeback: implement unlocked_inode_to_wb transaction and use it for stat updates
  writeback: implement [locked_]inode_to_wb_and_lock_list()
  writeback: implement foreign cgroup inode detection
  writeback: make writeback_control track the inode being written back
  writeback: relocate wb[_try]_get(), wb_put(), inode_{attach|detach}_wb()
  mm: vmscan: disable memcg direct reclaim stalling if cgroup writeback support is in use
  writeback: implement memcg writeback domain based throttling
  writeback: reset wb_domain->dirty_limit[_tstmp] when memcg domain size changes
  writeback: implement memcg wb_domain
  writeback: update wb_over_bg_thresh() to use wb_domain aware operations
  ...
2015-06-25 16:00:17 -07:00
Rasmus Villemoes 97b4af2f76 ext4: mballoc: avoid 20-argument function call
Making a function call with 20 arguments is rather expensive in both
stack and .text. In this case, doing the formatting manually doesn't
make it any less readable, so we might as well save 155 bytes of .text
and 112 bytes of stack.

Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
2015-06-15 00:32:58 -04:00
Lukas Czerner 42ac1848ea ext4: return error code from ext4_mb_good_group()
Currently ext4_mb_good_group() only returns 0 or 1 depending on whether
the allocation group is suitable for use or not. However we might get
various errors and fail while initializing new group including -EIO
which would never get propagated up the call chain. This might lead to
an endless loop at writeback when we're trying to find a good group to
allocate from and we fail to initialize new group (read error for
example).

Fix this by returning proper error code from ext4_mb_good_group() and
using it in ext4_mb_regular_allocator(). In ext4_mb_regular_allocator()
we will always return only the first occurred error from
ext4_mb_good_group() and we only propagate it back  to the caller if we
do not get any other errors and we fail to allocate any blocks.

Note that with other modes than errors=continue, we will fail
immediately in ext4_mb_good_group() in case of error, however with
errors=continue we should try to continue using the file system, that's
why we're not going to fail immediately when we see an error from
ext4_mb_good_group(), but rather when we fail to find a suitable block
group to allocate from due to an problem in group initialization.

Signed-off-by: Lukas Czerner <lczerner@redhat.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
2015-06-08 11:40:40 -04:00
Lukas Czerner bbdc322f2c ext4: try to initialize all groups we can in case of failure on ppc64
Currently on the machines with page size > block size when initializing
block group buddy cache we initialize it for all the block group bitmaps
in the page. However in the case of read error, checksum error, or if
a single bitmap is in any way corrupted we would fail to initialize all
of the bitmaps. This is problematic because we will not have access to
the other allocation groups even though those might be perfectly fine
and usable.

Fix this by reading all the bitmaps instead of error out on the first
problem and simply skip the bitmaps which were either not read properly,
or are not valid.

Signed-off-by: Lukas Czerner <lczerner@redhat.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2015-06-08 11:38:37 -04:00
Tejun Heo 66114cad64 writeback: separate out include/linux/backing-dev-defs.h
With the planned cgroup writeback support, backing-dev related
declarations will be more widely used across block and cgroup;
unfortunately, including backing-dev.h from include/linux/blkdev.h
makes cyclic include dependency quite likely.

This patch separates out backing-dev-defs.h which only has the
essential definitions and updates blkdev.h to include it.  c files
which need access to more backing-dev details now include
backing-dev.h directly.  This takes backing-dev.h off the common
include dependency chain making it a lot easier to use it across block
and cgroup.

v2: fs/fat build failure fixed.

Signed-off-by: Tejun Heo <tj@kernel.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Cc: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Jens Axboe <axboe@fb.com>
2015-06-02 08:33:34 -06:00
Markus Elfring bfcba2d035 ext4: Remove an unnecessary check for NULL before iput()
The iput() function tests whether its argument is NULL and then
returns immediately. Thus the test around the call is not needed.

This issue was detected by using the Coccinelle software.

Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2014-11-25 20:01:37 -05:00
Dmitry Monakhov 4fdb554318 ext4: cleanup GFP flags inside resize path
We must use GFP_NOFS instead GFP_KERNEL inside ext4_mb_add_groupinfo
and ext4_calculate_overhead() because they are called from inside a
journal transaction. Call trace:

ioctl
 ->ext4_group_add
   ->journal_start
   ->ext4_setup_new_descs
     ->ext4_mb_add_groupinfo -> GFP_KERNEL
   ->ext4_flex_group_add
     ->ext4_update_super
       ->ext4_calculate_overhead  -> GFP_KERNEL
   ->journal_stop

Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2014-11-25 13:08:04 -05:00
Al Viro b93b41d4c7 ext4: kill ext4_kvfree()
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2014-11-20 12:19:11 -05:00
Linus Torvalds c2661b8060 A large number of cleanups and bug fixes, with some (minor) journal
optimizations.
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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:
 "A large number of cleanups and bug fixes, with some (minor) journal
  optimizations"

[ This got sent to me before -rc1, but was stuck in my spam folder.   - Linus ]

* tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: (67 commits)
  ext4: check s_chksum_driver when looking for bg csum presence
  ext4: move error report out of atomic context in ext4_init_block_bitmap()
  ext4: Replace open coded mdata csum feature to helper function
  ext4: delete useless comments about ext4_move_extents
  ext4: fix reservation overflow in ext4_da_write_begin
  ext4: add ext4_iget_normal() which is to be used for dir tree lookups
  ext4: don't orphan or truncate the boot loader inode
  ext4: grab missed write_count for EXT4_IOC_SWAP_BOOT
  ext4: optimize block allocation on grow indepth
  ext4: get rid of code duplication
  ext4: fix over-defensive complaint after journal abort
  ext4: fix return value of ext4_do_update_inode
  ext4: fix mmap data corruption when blocksize < pagesize
  vfs: fix data corruption when blocksize < pagesize for mmaped data
  ext4: fold ext4_nojournal_sops into ext4_sops
  ext4: support freezing ext2 (nojournal) file systems
  ext4: fold ext4_sync_fs_nojournal() into ext4_sync_fs()
  ext4: don't check quota format when there are no quota files
  jbd2: simplify calling convention around __jbd2_journal_clean_checkpoint_list
  jbd2: avoid pointless scanning of checkpoint lists
  ...
2014-10-20 09:50:11 -07:00
Linus Torvalds 0429fbc0bd Merge branch 'for-3.18-consistent-ops' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu
Pull percpu consistent-ops changes from Tejun Heo:
 "Way back, before the current percpu allocator was implemented, static
  and dynamic percpu memory areas were allocated and handled separately
  and had their own accessors.  The distinction has been gone for many
  years now; however, the now duplicate two sets of accessors remained
  with the pointer based ones - this_cpu_*() - evolving various other
  operations over time.  During the process, we also accumulated other
  inconsistent operations.

  This pull request contains Christoph's patches to clean up the
  duplicate accessor situation.  __get_cpu_var() uses are replaced with
  with this_cpu_ptr() and __this_cpu_ptr() with raw_cpu_ptr().

  Unfortunately, the former sometimes is tricky thanks to C being a bit
  messy with the distinction between lvalues and pointers, which led to
  a rather ugly solution for cpumask_var_t involving the introduction of
  this_cpu_cpumask_var_ptr().

  This converts most of the uses but not all.  Christoph will follow up
  with the remaining conversions in this merge window and hopefully
  remove the obsolete accessors"

* 'for-3.18-consistent-ops' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu: (38 commits)
  irqchip: Properly fetch the per cpu offset
  percpu: Resolve ambiguities in __get_cpu_var/cpumask_var_t -fix
  ia64: sn_nodepda cannot be assigned to after this_cpu conversion. Use __this_cpu_write.
  percpu: Resolve ambiguities in __get_cpu_var/cpumask_var_t
  Revert "powerpc: Replace __get_cpu_var uses"
  percpu: Remove __this_cpu_ptr
  clocksource: Replace __this_cpu_ptr with raw_cpu_ptr
  sparc: Replace __get_cpu_var uses
  avr32: Replace __get_cpu_var with __this_cpu_write
  blackfin: Replace __get_cpu_var uses
  tile: Use this_cpu_ptr() for hardware counters
  tile: Replace __get_cpu_var uses
  powerpc: Replace __get_cpu_var uses
  alpha: Replace __get_cpu_var
  ia64: Replace __get_cpu_var uses
  s390: cio driver &__get_cpu_var replacements
  s390: Replace __get_cpu_var uses
  mips: Replace __get_cpu_var uses
  MIPS: Replace __get_cpu_var uses in FPU emulator.
  arm: Replace __this_cpu_ptr with raw_cpu_ptr
  ...
2014-10-15 07:48:18 +02:00
Dmitry Monakhov dfe076c106 ext4: get rid of code duplication
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2014-10-01 22:26:17 -04:00
Theodore Ts'o 754cfed6bb ext4: drop the EXT4_STATE_DELALLOC_RESERVED flag
Having done a full regression test, we can now drop the
DELALLOC_RESERVED state flag.

Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Jan Kara <jack@suse.cz>
2014-09-04 18:08:22 -04:00
Theodore Ts'o e3cf5d5d9a ext4: prepare to drop EXT4_STATE_DELALLOC_RESERVED
The EXT4_STATE_DELALLOC_RESERVED flag was originally implemented
because it was too hard to make sure the mballoc and get_block flags
could be reliably passed down through all of the codepaths that end up
calling ext4_mb_new_blocks().

Since then, we have mb_flags passed down through most of the code
paths, so getting rid of EXT4_STATE_DELALLOC_RESERVED isn't as tricky
as it used to.

This commit plumbs in the last of what is required, and then adds a
WARN_ON check to make sure we haven't missed anything.  If this passes
a full regression test run, we can then drop
EXT4_STATE_DELALLOC_RESERVED.

Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Jan Kara <jack@suse.cz>
2014-09-04 18:07:25 -04:00
Christoph Lameter a0b6bc63a2 block: Replace __this_cpu_ptr with raw_cpu_ptr
__this_cpu_ptr is being phased out use raw_cpu_ptr instead which was
introduced in 3.15-rc1.

Cc: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Christoph Lameter <cl@linux.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
2014-08-26 13:45:45 -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 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
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
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 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
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
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
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
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
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
jon ernst e2cbd58741 ext4: silence sparse check warning for function ext4_trim_extent
This fixes the following sparse warning:

     CHECK   fs/ext4/mballoc.c
   fs/ext4/mballoc.c:5019:9: warning: context imbalance in
   'ext4_trim_extent' - unexpected unlock

Signed-off-by: "Jon Ernst" <jonernst07@gmail.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2014-04-12 23:01:28 -04:00
Younger Liu c57ab39b96 ext4: return ENOMEM rather than EIO when find_###_page() fails
Return ENOMEM rather than EIO when find_get_page() fails in
ext4_mb_get_buddy_page_lock() and find_or_create_page() fails in
ext4_mb_load_buddy().

Signed-off-by: Younger Liu <younger.liucn@gmail.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2014-04-10 23:03:43 -04:00
Eric Sandeen dc9ddd984d ext4: remove unused ac_ex_scanned
When looking at a bug report with:

> kernel: EXT4-fs: 0 scanned, 0 found

I thought wow, 0 scanned, that's odd?  But it's not odd; it's printing
a variable that is initialized to 0 and never touched again.

It's never been used since the original merge, so I don't really even
know what the original intent was, either.

If anyone knows how to hook it up, speak now via patch, otherwise just
yank it so it's not making a confusing situation more confusing in
kernel logs.

Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2014-02-20 13:32:10 -05:00
Theodore Ts'o ab0c00fccf ext4: make sure ex.fe_logical is initialized
The lowest levels of mballoc set all of the fields of struct
ext4_free_extent except for fe_logical, since they are just trying to
find the requested free set of blocks, and the logical block hasn't
been set yet.  This makes some static code checkers sad.  Set it to
various different debug values, which would be useful when
debugging mballoc if these values were to ever show up due to the
parts of mballoc triyng to use ac->ac_b_ex.fe_logical before it is
properly upper layers of mballoc failing to properly set, usually by
ext4_mb_use_best_found().

Addresses-Coverity-Id: #139697
Addresses-Coverity-Id: #139698
Addresses-Coverity-Id: #139699

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2014-02-20 00:36:41 -05:00
Theodore Ts'o f5a44db5d2 ext4: add explicit casts when masking cluster sizes
The missing casts can cause the high 64-bits of the physical blocks to
be lost.  Set up new macros which allows us to make sure the right
thing happen, even if at some point we end up supporting larger
logical block numbers.

Thanks to the Emese Revfy and the PaX security team for reporting this
issue.

Reported-by: PaX Team <pageexec@freemail.hu>
Reported-by: Emese Revfy <re.emese@gmail.com>                                 
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Cc: stable@vger.kernel.org
2013-12-20 09:29:35 -05:00
Junho Ryu 4e8d213980 ext4: fix use-after-free in ext4_mb_new_blocks
ext4_mb_put_pa should hold pa->pa_lock before accessing pa->pa_count.
While ext4_mb_use_preallocated checks pa->pa_deleted first and then
increments pa->count later, ext4_mb_put_pa decrements pa->pa_count
before holding pa->pa_lock and then sets pa->pa_deleted.

* Free sequence
ext4_mb_put_pa (1):		atomic_dec_and_test pa->pa_count
ext4_mb_put_pa (2):		lock pa->pa_lock
ext4_mb_put_pa (3):			check pa->pa_deleted
ext4_mb_put_pa (4):			set pa->pa_deleted=1
ext4_mb_put_pa (5):		unlock pa->pa_lock
ext4_mb_put_pa (6):		remove pa from a list
ext4_mb_pa_callback:		free pa

* Use sequence
ext4_mb_use_preallocated (1):	iterate over preallocation
ext4_mb_use_preallocated (2):	lock pa->pa_lock
ext4_mb_use_preallocated (3):		check pa->pa_deleted
ext4_mb_use_preallocated (4):		increase pa->pa_count
ext4_mb_use_preallocated (5):	unlock pa->pa_lock
ext4_mb_release_context:	access pa

* Use-after-free sequence
[initial status]		<pa->pa_deleted = 0, pa_count = 1>
ext4_mb_use_preallocated (1):	iterate over preallocation
ext4_mb_use_preallocated (2):	lock pa->pa_lock
ext4_mb_use_preallocated (3):		check pa->pa_deleted
ext4_mb_put_pa (1):		atomic_dec_and_test pa->pa_count
[pa_count decremented]		<pa->pa_deleted = 0, pa_count = 0>
ext4_mb_use_preallocated (4):		increase pa->pa_count
[pa_count incremented]		<pa->pa_deleted = 0, pa_count = 1>
ext4_mb_use_preallocated (5):	unlock pa->pa_lock
ext4_mb_put_pa (2):		lock pa->pa_lock
ext4_mb_put_pa (3):			check pa->pa_deleted
ext4_mb_put_pa (4):			set pa->pa_deleted=1
[race condition!]		<pa->pa_deleted = 1, pa_count = 1>
ext4_mb_put_pa (5):		unlock pa->pa_lock
ext4_mb_put_pa (6):		remove pa from a list
ext4_mb_pa_callback:		free pa
ext4_mb_release_context:	access pa

AddressSanitizer has detected use-after-free in ext4_mb_new_blocks
Bug report: http://goo.gl/rG1On3

Signed-off-by: Junho Ryu <jayr@google.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Cc: stable@vger.kernel.org
2013-12-03 18:10:28 -05:00
Lukas Czerner 8f9ff18920 ext4: fix FITRIM in no journal mode
When using FITRIM ioctl on a file system without journal it will
only trim the block group once, no matter how many times you invoke
FITRIM ioctl and how many block you release from the block group.

It is because we only clear EXT4_GROUP_INFO_WAS_TRIMMED_BIT in journal
callback. Fix this by clearing the bit in no journal mode as well.

Signed-off-by: Lukas Czerner <lczerner@redhat.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Reported-by: Jorge Fábregas <jorge.fabregas@gmail.com>
2013-10-30 11:10:52 -04:00
Darrick J. Wong 163a203ddb ext4: mark block group as corrupt on block bitmap error
When we notice a block-bitmap corruption (because of device failure or
something else), we should mark this group as corrupt and prevent
further block allocations/deallocations from it. Currently, we end up
generating one error message for every block in the bitmap. This
potentially could make the system unstable as noticed in some
bugs. With this patch, the error will be printed only the first time
and mark the entire block group as corrupted. This prevents future
access allocations/deallocations from it.

Also tested by corrupting the block
bitmap and forcefully introducing the mb_free_blocks error:
(1) create a largefile (2Gb)
$ dd if=/dev/zero of=largefile oflag=direct bs=10485760 count=200
(2) umount filesystem. use dumpe2fs to see which block-bitmaps
are in use by largefile and note their block numbers
(3) use dd to zero-out the used block bitmaps
$ dd if=/dev/zero of=/dev/hdc4 bs=4096 seek=14 count=8 oflag=direct
(4) mount the FS and delete the largefile.
(5) recreate the largefile. verify that the new largefile does not
get any blocks from the groups marked as bad.
Without the patch, we will see mb_free_blocks error for each bit in
each zero'ed out bitmap at (4). With the patch, we only see the error
once per blockgroup:
[  309.706803] EXT4-fs error (device sdb4): ext4_mb_generate_buddy:735: group 15: 32768 clusters in bitmap, 0 in gd. blk grp corrupted.
[  309.720824] EXT4-fs error (device sdb4): ext4_mb_generate_buddy:735: group 14: 32768 clusters in bitmap, 0 in gd. blk grp corrupted.
[  309.732858] EXT4-fs error (device sdb4) in ext4_free_blocks:4802: IO failure
[  309.748321] EXT4-fs error (device sdb4): ext4_mb_generate_buddy:735: group 13: 32768 clusters in bitmap, 0 in gd. blk grp corrupted.
[  309.760331] EXT4-fs error (device sdb4) in ext4_free_blocks:4802: IO failure
[  309.769695] EXT4-fs error (device sdb4): ext4_mb_generate_buddy:735: group 12: 32768 clusters in bitmap, 0 in gd. blk grp corrupted.
[  309.781721] EXT4-fs error (device sdb4) in ext4_free_blocks:4802: IO failure
[  309.798166] EXT4-fs error (device sdb4): ext4_mb_generate_buddy:735: group 11: 32768 clusters in bitmap, 0 in gd. blk grp corrupted.
[  309.810184] EXT4-fs error (device sdb4) in ext4_free_blocks:4802: IO failure
[  309.819532] EXT4-fs error (device sdb4): ext4_mb_generate_buddy:735: group 10: 32768 clusters in bitmap, 0 in gd. blk grp corrupted.

Google-Bug-Id: 7258357

[darrick.wong@oracle.com]
Further modifications (by Darrick) to make more obvious that this corruption
bit applies to blocks only.  Set the corruption flag if the block group bitmap
verification fails.

Original-author: Aditya Kali <adityakali@google.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2013-08-28 17:35:51 -04:00
Jan Kara 7d7345322d ext4: fix warning in ext4_da_update_reserve_space()
reaim workfile.dbase test easily triggers warning in
ext4_da_update_reserve_space():

EXT4-fs warning (device ram0): ext4_da_update_reserve_space:365:
ino 12, allocated 1 with only 0 reserved metadata blocks (releasing 1
blocks with reserved 9 data blocks)

The problem is that (one of) tests creates file and then randomly writes
to it with O_SYNC. That results in writing back pages of the file in
random order so we create extents for written blocks say 0, 2, 4, 6, 8
- this last allocation also allocates new block for extents. Then we
writeout block 1 so we have extents 0-2, 4, 6, 8 and we release
indirect extent block because extents fit in the inode again. Then we
writeout block 10 and we need to allocate indirect extent block again
which triggers the warning because we don't have the reservation
anymore.

Fix the problem by giving back freed metadata blocks resulting from
extent merging into inode's reservation pool.

Signed-off-by: Jan Kara <jack@suse.cz>
2013-08-17 09:36:54 -04:00