linux-toradex.git/fs/ext4/resize.c, branch v3.5.1

ext4: fix overhead calculation used by ext4_statfs()

2012-08-09T15:23:12+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: 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"

ext4: fix potential integer overflow in alloc_flex_gd()

2012-05-28T18:21:55+00:00

In alloc_flex_gd(), when flexbg_size is large, kmalloc size would
overflow and flex_gd->groups would point to a buffer smaller than
expected, causing OOB accesses when it is used.

Note that in ext4_resize_fs(), flexbg_size is calculated using
sbi->s_log_groups_per_flex, which is read from the disk and only bounded
to [1, 31]. The patch returns NULL for too large flexbg_size.

Reviewed-by: Eric Sandeen 
Signed-off-by: Haogang Chen 
Signed-off-by: "Theodore Ts'o" 
Cc: stable@kernel.org

ext4: make block group checksums use metadata_csum algorithm

2012-04-29T22:45:10+00:00

metadata_csum supersedes uninit_bg.  Convert the ROCOMPAT uninit_bg
flag check to a helper function that covers both, and make the
checksum calculation algorithm use either crc16 or the metadata_csum
chosen algorithm depending on which flag is set.  Print a warning if
we try to mount a filesystem with both feature flags set.

Signed-off-by: Darrick J. Wong 
Signed-off-by: "Theodore Ts'o"

ext4: calculate and verify block bitmap checksum

2012-04-29T22:35:10+00:00

Compute and verify the checksum of the block bitmap; this checksum is
stored in the block group descriptor.

Signed-off-by: Darrick J. Wong 
Signed-off-by: "Theodore Ts'o"

ext4: calculate and verify checksums for inode bitmaps

2012-04-29T22:33:10+00:00

Compute and verify the checksum of the inode bitmap; the checkum is
stored in the block group descriptor.

Signed-off-by: Darrick J. Wong 
Signed-off-by: "Theodore Ts'o"

ext4: calculate and verify superblock checksum

2012-04-29T22:29:10+00:00

Calculate and verify the superblock checksum.  Since the UUID and
block group number are embedded in each copy of the superblock, we
need only checksum the entire block.  Refactor some of the code to
eliminate open-coding of the checksum update call.

Signed-off-by: Darrick J. Wong 
Signed-off-by: "Theodore Ts'o"

ext4: update s_free_{inodes,blocks}_count during online resize

2012-03-20T19:46:11+00:00

When we're doing an online resize of an ext4 filesystem, we need to
update the free inode and block counts in the superblock so that fsck
doesn't complain.

Signed-off-by: Darrick J. Wong 
Signed-off-by: "Theodore Ts'o"

ext4: change some printk() calls to use ext4_msg() instead

2012-03-20T03:41:49+00:00

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

ext4: fix resize when resizing within single group

2012-02-21T04:02:06+00:00

When resizing file system in the way that the new size of the file
system is still in the same group (no new groups are added), then we can
hit a BUG_ON in ext4_alloc_group_tables()

BUG_ON(flex_gd->count == 0 || group_data == NULL);

because flex_gd->count is zero. The reason is the missing check for such
case, so the code always extend the last group fully and then attempt to
add more groups, but at that time n_blocks_count is actually smaller
than o_blocks_count.

It can be easily reproduced like this:

mkfs.ext4 -b 4096 /dev/sda 30M
mount /dev/sda /mnt/test
resize2fs /dev/sda 50M

Fix this by checking whether the resize happens within the singe group
and only add that many blocks into the last group to satisfy user
request. Then o_blocks_count == n_blocks_count and the resize will exit
successfully without and attempt to add more groups into the fs.

Also fix mixing together block number and blocks count which might be
confusing and can easily lead to off-by-one errors (but it is actually
not the case here since the two occurrence of this mix-up will cancel
each other).

Signed-off-by: Lukas Czerner 
Reported-by: Milan Broz 
Reviewed-by: Eric Sandeen 
Signed-off-by: "Theodore Ts'o"