aha/fs/ext2
Mingming Cao d707d31c97 ext2: fix ext2 block reservation early ENOSPC issue
We could run into ENOSPC error on ext2, even when there is free blocks on
the filesystem.

The problem is triggered in the case the goal block group has 0 free
blocks , and the rest block groups are skipped due to the check of
"free_blocks < windowsz/2".  Current code could fall back to non
reservation allocation to prevent early ENOSPC after examing all the block
groups with reservation on , but this code was bypassed if the reservation
window is turned off already, which is true in this case.

This patch fixed two issues:
1) We don't need to turn off block reservation if the goal block group has
0 free blocks left and continue search for the rest of block groups.

Current code the intention is to turn off the block reservation if the
goal allocation group has a few (some) free blocks left (not enough for
make the desired reservation window),to try to allocation in the goal
block group, to get better locality.  But if the goal blocks have 0 free
blocks, it should leave the block reservation on, and continues search for
the next block groups,rather than turn off block reservation completely.

2) we don't need to check the window size if the block reservation is off.

The problem was originally found and fixed in ext4.

Signed-off-by: Mingming Cao <cmm@us.ibm.com>
Cc: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-16 11:21:45 -07:00
..
acl.c [PATCH] sanitize ->permission() prototype 2008-07-26 20:53:14 -04:00
acl.h [PATCH] sanitize ->permission() prototype 2008-07-26 20:53:14 -04:00
balloc.c ext2: fix ext2 block reservation early ENOSPC issue 2008-10-16 11:21:45 -07:00
dir.c ext2: replace remaining __FUNCTION__ occurrences 2008-04-28 08:58:43 -07:00
ext2.h generic block based fiemap implementation 2008-10-03 17:32:43 -04:00
file.c generic block based fiemap implementation 2008-10-03 17:32:43 -04:00
fsync.c header cleaning: don't include smp_lock.h when not used 2007-05-08 11:15:07 -07:00
ialloc.c ext2: le*_add_cpu conversion 2008-04-28 08:58:43 -07:00
inode.c generic block based fiemap implementation 2008-10-03 17:32:43 -04:00
ioctl.c [PATCH] r/o bind mounts: elevate write count for ioctls() 2008-04-19 00:29:24 -04:00
Makefile [PATCH] Make EXT2_DEBUG work again 2006-06-25 10:01:12 -07:00
namei.c iget: stop EXT2 from using iget() and read_inode() 2008-02-07 08:42:27 -08:00
super.c vfs: Use const for kernel parser table 2008-10-13 10:10:37 -07:00
symlink.c [PATCH] mark struct inode_operations const 1 2007-02-12 09:48:46 -08:00
xattr.c ext2: use ext2_group_first_block_no() 2008-04-28 08:58:43 -07:00
xattr.h Remove obsolete #include <linux/config.h> 2006-06-30 19:25:36 +02:00
xattr_security.c ext2: remove double definitions of xattr macros 2008-07-25 10:53:31 -07:00
xattr_trusted.c ext2: remove double definitions of xattr macros 2008-07-25 10:53:31 -07:00
xattr_user.c ext2: remove double definitions of xattr macros 2008-07-25 10:53:31 -07:00
xip.c ext2: replace remaining __FUNCTION__ occurrences 2008-04-28 08:58:43 -07:00
xip.h xip: support non-struct page backed memory 2008-04-28 08:58:23 -07:00