linux-stable.git/fs/ext4, branch v3.4.8

ext4: undo ext4_calc_metadata_amount if we fail to claim space

2012-08-09T15:31:41+00:00

commit 03179fe92318e7934c180d96f12eff2cb36ef7b6 upstream.

The function ext4_calc_metadata_amount() has side effects, although
it's not obvious from its function name.  So if we fail to claim
space, regardless of whether we retry to claim the space again, or
return an error, we need to undo these side effects.

Otherwise we can end up incorrectly calculating the number of metadata
blocks needed for the operation, which was responsible for an xfstests
failure for test #271 when using an ext2 file system with delalloc
enabled.

Reported-by: Brian Foster 
Signed-off-by: "Theodore Ts'o" 
Signed-off-by: Greg Kroah-Hartman

ext4: don't let i_reserved_meta_blocks go negative

2012-08-09T15:31:41+00:00

commit 97795d2a5b8d3c8dc4365d4bd3404191840453ba upstream.

If we hit a condition where we have allocated metadata blocks that
were not appropriately reserved, we risk underflow of
ei->i_reserved_meta_blocks.  In turn, this can throw
sbi->s_dirtyclusters_counter significantly out of whack and undermine
the nondelalloc fallback logic in ext4_nonda_switch().  Warn if this
occurs and set i_allocated_meta_blocks to avoid this problem.

This condition is reproduced by xfstests 270 against ext2 with
delalloc enabled:

Mar 28 08:58:02 localhost kernel: [  171.526344] EXT4-fs (loop1): delayed block allocation failed for inode 14 at logical offset 64486 with max blocks 64 with error -28
Mar 28 08:58:02 localhost kernel: [  171.526346] EXT4-fs (loop1): This should not happen!! Data will be lost

270 ultimately fails with an inconsistent filesystem and requires an
fsck to repair.  The cause of the error is an underflow in
ext4_da_update_reserve_space() due to an unreserved meta block
allocation.

Signed-off-by: Brian Foster 
Signed-off-by: "Theodore Ts'o" 
Signed-off-by: Greg Kroah-Hartman

ext4: fix hole punch failure when depth is greater than 0

2012-08-09T15:31:41+00:00

commit 968dee77220768a5f52cf8b21d0bdb73486febef upstream.

Whether to continue removing extents or not is decided by the return
value of function ext4_ext_more_to_rm() which checks 2 conditions:
a) if there are no more indexes to process.
b) if the number of entries are decreased in the header of "depth -1".

In case of hole punch, if the last block to be removed is not part of
the last extent index than this index will not be deleted, hence the
number of valid entries in the extent header of "depth - 1" will
remain as it is and ext4_ext_more_to_rm will return 0 although the
required blocks are not yet removed.

This patch fixes the above mentioned problem as instead of removing
the extents from the end of file, it starts removing the blocks from
the particular extent from which removing blocks is actually required
and continue backward until done.

Signed-off-by: Ashish Sangwan 
Signed-off-by: Namjae Jeon 
Reviewed-by: Lukas Czerner 
Signed-off-by: Greg Kroah-Hartman

ext4: fix overhead calculation used by ext4_statfs()

2012-08-09T15:31:41+00:00

commit 952fc18ef9ec707ebdc16c0786ec360295e5ff15 upstream.

Commit f975d6bcc7a introduced bug which caused ext4_statfs() to
miscalculate the number of file system overhead blocks.  This causes
the f_blocks field in the statfs structure to be larger than it should
be.  This would in turn cause the "df" output to show the number of
data blocks in the file system and the number of data blocks used to
be larger than they should be.

Signed-off-by: "Theodore Ts'o" 
Signed-off-by: Greg Kroah-Hartman

ext4: pass a char * to ext4_count_free() instead of a buffer_head ptr

2012-08-09T15:31:40+00:00

commit f6fb99cadcd44660c68e13f6eab28333653621e6 upstream.

Make it possible for ext4_count_free to operate on buffers and not
just data in buffer_heads.

Signed-off-by: "Theodore Ts'o" 
Signed-off-by: Greg Kroah-Hartman

ext4: fix duplicated mnt_drop_write call in EXT4_IOC_MOVE_EXT

2012-07-29T15:04:19+00:00

commit 331ae4962b975246944ea039697a8f1cadce42bb upstream.

Caused, AFAICS, by mismerge in commit ff9cb1c4eead ("Merge branch
'for_linus' into for_linus_merged")

Signed-off-by: Al Viro 
Cc: Theodore Ts'o 
Signed-off-by: Linus Torvalds 
Signed-off-by: Greg Kroah-Hartman

ext4: fix the free blocks calculation for ext3 file systems w/ uninit_bg

2012-06-17T18:21:23+00:00

commit b0dd6b70f0fda17ae9762fbb72d98e40a4f66556 upstream.

Ext3 filesystems that are converted to use as many ext4 file system
features as possible will enable uninit_bg to speed up e2fsck times.
These file systems will have a native ext3 layout of inode tables and
block allocation bitmaps (as opposed to ext4's flex_bg layout).
Unfortunately, in these cases, when first allocating a block in an
uninitialized block group, ext4 would incorrectly calculate the number
of free blocks in that block group, and then errorneously report that
the file system was corrupt:

EXT4-fs error (device vdd): ext4_mb_generate_buddy:741: group 30, 32254 clusters in bitmap, 32258 in gd

This problem can be reproduced via:

    mke2fs -q -t ext4 -O ^flex_bg /dev/vdd 5g
    mount -t ext4 /dev/vdd /mnt
    fallocate -l 4600m /mnt/test

The problem was caused by a bone headed mistake in the check to see if a
particular metadata block was part of the block group.

Many thanks to Kees Cook for finding and bisecting the buggy commit
which introduced this bug (commit fd034a84e1, present since v3.2).

Reported-by: Sander Eikelenboom 
Reported-by: Kees Cook 
Signed-off-by: "Theodore Ts'o" 
Tested-by: Kees Cook 
Signed-off-by: Greg Kroah-Hartman

ext4: don't set i_flags in EXT4_IOC_SETFLAGS

2012-06-09T15:36:19+00:00

commit b22b1f178f6799278d3178d894f37facb2085765 upstream.

Commit 7990696 uses the ext4_{set,clear}_inode_flags() functions to
change the i_flags automatically but fails to remove the error setting
of i_flags.  So we still have the problem of trashing state flags.
Fix this by removing the assignment.

Signed-off-by: Tao Ma 
Signed-off-by: "Theodore Ts'o" 
Signed-off-by: Greg Kroah-Hartman

ext4: remove mb_groups before tearing down the buddy_cache

2012-06-09T15:36:16+00:00

commit 95599968d19db175829fb580baa6b68939b320fb upstream.

We can't have references held on pages in the s_buddy_cache while we are
trying to truncate its pages and put the inode.  All the pages must be
gone before we reach clear_inode.  This can only be gauranteed if we
can prevent new users from grabbing references to s_buddy_cache's pages.

The original bug can be reproduced and the bug fix can be verified by:

while true; do mount -t ext4 /dev/ram0 /export/hda3/ram0; \
	umount /export/hda3/ram0; done &

while true; do cat /proc/fs/ext4/ram0/mb_groups; done

Signed-off-by: Salman Qazi 
Signed-off-by: "Theodore Ts'o" 
Signed-off-by: Greg Kroah-Hartman

ext4: add ext4_mb_unload_buddy in the error path

2012-06-09T15:36:16+00:00

commit 02b7831019ea4e7994968c84b5826fa8b248ffc8 upstream.

ext4_free_blocks fails to pair an ext4_mb_load_buddy with a matching
ext4_mb_unload_buddy when it fails a memory allocation.

Signed-off-by: Salman Qazi 
Signed-off-by: "Theodore Ts'o" 
Signed-off-by: Greg Kroah-Hartman