2006-11-21 17:17:03

by Andrew Morton

[permalink] [raw]
Subject: + ext4-fix-reservation-extension.patch added to -mm tree


The patch titled
ext4: fix reservation extension
has been added to the -mm tree. Its filename is
ext4-fix-reservation-extension.patch

See http://www.zip.com.au/~akpm/linux/patches/stuff/added-to-mm.txt to find
out what to do about this

------------------------------------------------------
Subject: ext4: fix reservation extension
From: Mingming Cao <[email protected]>

Hugh Dickins wrote:
> Not found anything relevant, but I keep noticing these lines
> in ext2_try_to_allocate_with_rsv(), ext3 and ext4 similar:
>
> } else if (grp_goal > 0 &&
> (my_rsv->rsv_end - grp_goal + 1) < *count)
> try_to_extend_reservation(my_rsv, sb,
> *count-my_rsv->rsv_end + grp_goal - 1);
>
> They're wrong, a no-op in most groups, aren't they? rsv_end is an
> absolute block number, whereas grp_goal is group-relative, so the
> calculation ought to bring in group_first_block? Or I'm confused.
>

Signed-off-by: Mingming Cao <[email protected]>
Cc: "[email protected]" <[email protected]>
Cc: Hugh Dickins <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
---

fs/ext4/balloc.c | 12 ++++++++----
1 file changed, 8 insertions(+), 4 deletions(-)

diff -puN fs/ext2/balloc.c~ext4-fix-reservation-extension fs/ext2/balloc.c
diff -puN fs/ext3/balloc.c~ext4-fix-reservation-extension fs/ext3/balloc.c
diff -puN fs/ext4/balloc.c~ext4-fix-reservation-extension fs/ext4/balloc.c
--- a/fs/ext4/balloc.c~ext4-fix-reservation-extension
+++ a/fs/ext4/balloc.c
@@ -1324,10 +1324,14 @@ ext4_try_to_allocate_with_rsv(struct sup
if (!goal_in_my_reservation(&my_rsv->rsv_window,
grp_goal, group, sb))
grp_goal = -1;
- } else if (grp_goal > 0 &&
- (my_rsv->rsv_end-grp_goal+1) < *count)
- try_to_extend_reservation(my_rsv, sb,
- *count-my_rsv->rsv_end + grp_goal - 1);
+ } else if (grp_goal > 0) {
+ int curr = my_rsv->rsv_end -
+ (grp_goal + group_first_block) + 1;
+
+ if (curr < *count)
+ try_to_extend_reservation(my_rsv, sb,
+ *count - curr);
+ }

if ((my_rsv->rsv_start > group_last_block) ||
(my_rsv->rsv_end < group_first_block)) {
_

Patches currently in -mm which might be from [email protected] are

ext3-fix-reservation-extension.patch
ext4-fix-reservation-extension.patch
ext2-reservations.patch
ext2-fix-reservation-extension.patch