linux-toradex.git/fs/ext4/mballoc.c, branch v3.0.75

ext4: use atomic64_t for the per-flexbg free_clusters count

2013-04-05T17:16:52+00:00

commit 90ba983f6889e65a3b506b30dc606aa9d1d46cd2 upstream.

A user who was using a 8TB+ file system and with a very large flexbg
size (> 65536) could cause the atomic_t used in the struct flex_groups
to overflow.  This was detected by PaX security patchset:

http://forums.grsecurity.net/viewtopic.php?f=3&t=3289&p=12551#p12551

This bug was introduced in commit 9f24e4208f7e, so it's been around
since 2.6.30.  :-(

Fix this by using an atomic64_t for struct orlav_stats's
free_clusters.

[Backported for 3.0-stable. Renamed free_clusters back to free_blocks;
fixed a few more atomic_read's of free_blocks left in 3.0.]

Signed-off-by: "Theodore Ts'o" 
Reviewed-by: Lukas Czerner 
Signed-off-by: Lingzhu Xiang 
Reviewed-by: CAI Qian 
Signed-off-by: Greg Kroah-Hartman

ext4: fix race in ext4_mb_add_n_trim()

2013-03-03T22:09:05+00:00

commit f1167009711032b0d747ec89a632a626c901a1ad upstream.

In ext4_mb_add_n_trim(), lg_prealloc_lock should be taken when
changing the lg_prealloc_list.

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

ext4: remove mb_groups before tearing down the buddy_cache

2012-06-09T15:33:04+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

2012-06-09T15:33:04+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

ext4: fix i_blocks/quota accounting when extent insertion fails

2011-08-05T04:58:39+00:00

commit 7132de744ba76930d13033061018ddd7e3e8cd91 upstream.

The current implementation of ext4_free_blocks() always calls
dquot_free_block This looks quite sensible in the most cases: blocks
to be freed are associated with inode and were accounted in quota and
i_blocks some time ago.

However, there is a case when blocks to free were not accounted by the
time calling ext4_free_blocks() yet:

1. delalloc is on, write_begin pre-allocated some space in quota
2. write-back happens, ext4 allocates some blocks in ext4_ext_map_blocks()
3. then ext4_ext_map_blocks() gets an error (e.g.  ENOSPC) from
   ext4_ext_insert_extent() and calls ext4_free_blocks().

In this scenario, ext4_free_blocks() calls dquot_free_block() who, in
turn, decrements i_blocks for blocks which were not accounted yet (due
to delalloc) After clean umount, e2fsck reports something like:

> Inode 21, i_blocks is 5080, should be 5128.  Fix?
because i_blocks was erroneously decremented as explained above.

The patch fixes the problem by passing the new flag
EXT4_FREE_BLOCKS_NO_QUOT_UPDATE to ext4_free_blocks(), to request
that the dquot_free_block() call be skipped.

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

ext4: fixed tracepoints cleanup

2011-06-06T13:51:52+00:00

While creating fixed tracepoints for ext3, basically by porting them
from ext4, I found a lot of useless retyping, wrong type usage, useless
variable passing and other inconsistencies in the ext4 fixed tracepoint
code.

This patch cleans the fixed tracepoint code for ext4 and also simplify
some of them.

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

ext4: correct comments for ext4_free_blocks()

2011-06-06T03:26:40+00:00

metadata is not parameter of ext4_free_blocks() any more.

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

ext4: add flag to ext4_has_free_blocks

2011-05-25T11:41:26+00:00

This patch adds an allocation request flag to the ext4_has_free_blocks
function which enables the use of reserved blocks.  This will allow a
punch hole to proceed even if the disk is full.  Punching a hole may
require additional blocks to first split the extents.

Because ext4_has_free_blocks is a low level function, the flag needs
to be passed down through several functions listed below:

ext4_ext_insert_extent
ext4_ext_create_new_leaf
ext4_ext_grow_indepth
ext4_ext_split
ext4_ext_new_meta_block
ext4_mb_new_blocks
ext4_claim_free_blocks
ext4_has_free_blocks

[ext4 punch hole patch series 1/5 v7]

Signed-off-by: Allison Henderson 
Signed-off-by: "Theodore Ts'o" 
Reviewed-by: Mingming Cao

ext4: protect bb_first_free in ext4_trim_all_free() with group lock

2011-05-24T22:28:07+00:00

We should protect reading bd_info->bb_first_free with the group lock
because otherwise we might miss some free blocks. This is not a big deal
at all, but the change to do right thing is really simple, so lets do
that.

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

ext4: only load buddy bitmap in ext4_trim_fs() when it is needed

2011-05-24T22:16:27+00:00

Currently we are loading buddy ext4_mb_load_buddy() for every block
group we are going through in ext4_trim_fs() in many cases just to find
out that there is not enough space to be bothered with. As Amir Goldstein
suggested we can use bb_free information directly from ext4_group_info.

This commit removes ext4_mb_load_buddy() from ext4_trim_fs() and rather
get the ext4_group_info via ext4_get_group_info() and use the bb_free
information directly from that. This avoids unnecessary call to load
buddy in the case the group does not have enough free space to trim.
Loading buddy is now moved to ext4_trim_all_free().

Tested by me with xfstests 251.

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