[PATCH 1/2 v2] ext4: check free block counters in ext4_mb_find_by_goal

[PATCH 1/2 v2] ext4: check free block counters in ext4_mb_find_by_goal

[Yongqiang Yang]

Free block counters should be checked before doing allocation.

Signed-off-by: Yongqiang Yang <xiaoqiangnk@gmail.com>
---
 fs/ext4/mballoc.c |    3 +++
 1 files changed, 3 insertions(+), 0 deletions(-)

diff --git a/fs/ext4/mballoc.c b/fs/ext4/mballoc.c
index 6873571..5d4c21a 100644
--- a/fs/ext4/mballoc.c
+++ b/fs/ext4/mballoc.c
@@ -1659,10 +1659,13 @@ int ext4_mb_find_by_goal(struct ext4_allocation_context *ac,
 	int max;
 	int err;
 	struct ext4_sb_info *sbi = EXT4_SB(ac->ac_sb);
+	struct ext4_group_info *grp = ext4_get_group_info(ac->ac_sb, group);
 	struct ext4_free_extent ex;
 
 	if (!(ac->ac_flags & EXT4_MB_HINT_TRY_GOAL))
 		return 0;
+	if (grp->bb_free == 0)
+		return 0;
 
 	err = ext4_mb_load_buddy(ac->ac_sb, group, e4b);
 	if (err)
-- 
1.7.5.1

[PATCH 2/2 v2] ext4: check free inode count before allocaing an inode

[Yongqiang Yang]

Recnetly, I ecountered some corrupted filesystems in which some
groups' free inode counts were 65535, it seemed that free inode
count was overflow.  This patch teaches ext4 to check free inode
count before allocaing an inode.

Signed-off-by: Yongqiang Yang <xiaoqiangnk@gmail.com>
---
 fs/ext4/ialloc.c |    9 +++++++++
 1 files changed, 9 insertions(+), 0 deletions(-)

diff --git a/fs/ext4/ialloc.c b/fs/ext4/ialloc.c
index 26154b8..fa36372 100644
--- a/fs/ext4/ialloc.c
+++ b/fs/ext4/ialloc.c
@@ -697,6 +697,15 @@ got_group:
 		if (!gdp)
 			goto fail;
 
+		/*
+		 * Check free inodes count before loading bitmap.
+		 */
+		if (ext4_free_inodes_count(sb, gdp) == 0) {
+			if (++group == ngroups)
+				group = 0;
+			continue;
+		}
+
 		brelse(inode_bitmap_bh);
 		inode_bitmap_bh = ext4_read_inode_bitmap(sb, group);
 		if (!inode_bitmap_bh)
-- 
1.7.5.1

Re: [PATCH 2/2 v2] ext4: check free inode count before allocaing an inode

[Theodore Ts'o]

On Thu, Sep 06, 2012 at 09:16:55PM +0800, Yongqiang Yang wrote:
> Recnetly, I ecountered some corrupted filesystems in which some
> groups' free inode counts were 65535, it seemed that free inode
> count was overflow.  This patch teaches ext4 to check free inode
> count before allocaing an inode.
> 
> Signed-off-by: Yongqiang Yang <xiaoqiangnk@gmail.com>

Thanks, applied.

						- Ted

Re: [PATCH 1/2 v2] ext4: check free block counters in ext4_mb_find_by_goal

[Theodore Ts'o]

On Thu, Sep 06, 2012 at 09:16:54PM +0800, Yongqiang Yang wrote:
> Free block counters should be checked before doing allocation.
> 
> Signed-off-by: Yongqiang Yang <xiaoqiangnk@gmail.com>

Thanks, applied.

						- Ted