ext4: Don't allow new groups to be added during block allocation

After we mark the blocks in the buddy cache as allocated,
we need to ensure that we don't reinit the buddy cache until
the block bitmap is updated.  This commit achieves this by holding
the group_info alloc_semaphore till ext4_mb_release_context

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Cc: stable@kernel.org
This commit is contained in:
Aneesh Kumar K.V
2009-01-05 21:46:55 -05:00
committed by Theodore Ts'o
parent 648f5879f5
commit 8556e8f3b6
2 changed files with 18 additions and 3 deletions

View File

@ -195,6 +195,11 @@ struct ext4_allocation_context {
__u8 ac_op; /* operation, for history only */
struct page *ac_bitmap_page;
struct page *ac_buddy_page;
/*
* pointer to the held semaphore upon successful
* block allocation
*/
struct rw_semaphore *alloc_semp;
struct ext4_prealloc_space *ac_pa;
struct ext4_locality_group *ac_lg;
};