linux-stable.git/fs/ext4/resize.c, branch linux-3.6.y

ext4: remove erroneous ext4_superblock_csum_set() in update_backups()

2012-12-03T19:38:15+00:00

commit bef53b01faeb791e27605cba1a71ba21364cb23e upstream.

The update_backups() function is used to backup all the metadata
blocks, so we should not take it for granted that 'data' is pointed to
a super block and use ext4_superblock_csum_set to calculate the
checksum there.  In case where the data is a group descriptor block,
it will corrupt the last group descriptor, and then e2fsck will
complain about it it.

As all the metadata checksums should already be OK when we do the
backup, remove the wrong ext4_superblock_csum_set and it should be
just fine.

Reported-by: "Theodore Ts'o" 
Signed-off-by: Tao Ma 
Signed-off-by: "Theodore Ts'o" 
Cc: Ben Hutchings 
Signed-off-by: Greg Kroah-Hartman

ext4: fix metadata checksum calculation for the superblock

2012-11-26T20:14:31+00:00

commit 06db49e68ae70cf16819b85a14057acb2820776a upstream.

The function ext4_handle_dirty_super() was calculating the superblock
on the wrong block data.  As a result, when the superblock is modified
while it is mounted (most commonly, when inodes are added or removed
from the orphan list), the superblock checksum would be wrong.  We
didn't notice because the superblock *was* being correctly calculated
in ext4_commit_super(), and this would get called when the file system
was unmounted.  So the problem only became obvious if the system
crashed while the file system was mounted.

Fix this by removing the poorly designed function signature for
ext4_superblock_csum_set(); if it only took a single argument, the
pointer to a struct superblock, the ambiguity which caused this
mistake would have been impossible.

Reported-by: George Spelvin 
Signed-off-by: "Theodore Ts'o" 
Tested-by: George Spelvin

ext4: Checksum the block bitmap properly with bigalloc enabled

2012-10-28T17:56:09+00:00

commit 79f1ba49569e5aec919b653c55b03274c2331701 upstream.

In mke2fs, we only checksum the whole bitmap block and it is right.
While in the kernel, we use EXT4_BLOCKS_PER_GROUP to indicate the
size of the checksumed bitmap which is wrong when we enable bigalloc.
The right size should be EXT4_CLUSTERS_PER_GROUP and this patch fixes
it.

Also as every caller of ext4_block_bitmap_csum_set and
ext4_block_bitmap_csum_verify pass in EXT4_BLOCKS_PER_GROUP(sb)/8,
we'd better removes this parameter and sets it in the function itself.

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

ext4: avoid duplicate writes of the backup bg descriptor blocks

2012-10-12T20:50:23+00:00

commit 2ebd1704ded88a8ae29b5f3998b13959c715c4be upstream.

The resize code was needlessly writing the backup block group
descriptor blocks multiple times (once per block group) during an
online resize.

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

ext4: don't copy non-existent gdt blocks when resizing

2012-10-12T20:50:23+00:00

commit 6df935ad2fced9033ab52078825fcaf6365f34b7 upstream.

The resize code was copying blocks at the beginning of each block
group in order to copy the superblock and block group descriptor table
(gdt) blocks.  This was, unfortunately, being done even for block
groups that did not have super blocks or gdt blocks.  This is a
complete waste of perfectly good I/O bandwidth, to skip writing those
blocks for sparse bg's.

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

ext4: ignore last group w/o enough space when resizing instead of BUG'ing

2012-10-12T20:50:23+00:00

commit 03c1c29053f678234dbd51bf3d65f3b7529021de upstream.

If the last group does not have enough space for group tables, ignore
it instead of calling BUG_ON().

Reported-by: Daniel Drake 
Signed-off-by: Yongqiang Yang 
Signed-off-by: "Theodore Ts'o" 
Signed-off-by: Greg Kroah-Hartman

ext4: remove unnecessary argument from __ext4_handle_dirty_metadata()

2012-07-23T00:37:31+00:00

The '__ext4_handle_dirty_metadata()' does not need the 'now' argument
anymore and we can kill it.

Signed-off-by: Artem Bityutskiy 
Signed-off-by: "Theodore Ts'o" 
Reviewed-by: Jan Kara

ext4: remove unused variable in ext4_update_super()

2012-07-23T00:23:31+00:00

Signed-off-by: "Theodore Ts'o"

ext4: fix overhead calculation used by ext4_statfs()

2012-07-09T20:27:05+00:00

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" 
Cc: stable@kernel.org

ext4: remove redundundant "(char *) bh->b_data" casts

2012-05-28T21:47:52+00:00

The b_data field of the buffer_head is already a char *, so there's no
point casting it to a char *.

Signed-off-by: "Theodore Ts'o"