diff options
Diffstat (limited to 'fs/ext4/mballoc.c')
| -rw-r--r-- | fs/ext4/mballoc.c | 157 |
1 files changed, 79 insertions, 78 deletions
diff --git a/fs/ext4/mballoc.c b/fs/ext4/mballoc.c index 381ac56..328ea9c 100644 --- a/fs/ext4/mballoc.c +++ b/fs/ext4/mballoc.c @@ -947,6 +947,85 @@ out: } /* + * lock the group_info alloc_sem of all the groups + * belonging to the same buddy cache page. This + * make sure other parallel operation on the buddy + * cache doesn't happen whild holding the buddy cache + * lock + */ +static int ext4_mb_get_buddy_cache_lock(struct super_block *sb, + ext4_group_t group) +{ + int i; + int block, pnum; + int blocks_per_page; + int groups_per_page; + ext4_group_t ngroups = ext4_get_groups_count(sb); + ext4_group_t first_group; + struct ext4_group_info *grp; + + blocks_per_page = PAGE_CACHE_SIZE / sb->s_blocksize; + /* + * the buddy cache inode stores the block bitmap + * and buddy information in consecutive blocks. + * So for each group we need two blocks. + */ + block = group * 2; + pnum = block / blocks_per_page; + first_group = pnum * blocks_per_page / 2; + + groups_per_page = blocks_per_page >> 1; + if (groups_per_page == 0) + groups_per_page = 1; + /* read all groups the page covers into the cache */ + for (i = 0; i < groups_per_page; i++) { + + if ((first_group + i) >= ngroups) + break; + grp = ext4_get_group_info(sb, first_group + i); + /* take all groups write allocation + * semaphore. This make sure there is + * no block allocation going on in any + * of that groups + */ + down_write_nested(&grp->alloc_sem, i); + } + return i; +} + +static void ext4_mb_put_buddy_cache_lock(struct super_block *sb, + ext4_group_t group, int locked_group) +{ + int i; + int block, pnum; + int blocks_per_page; + ext4_group_t first_group; + struct ext4_group_info *grp; + + blocks_per_page = PAGE_CACHE_SIZE / sb->s_blocksize; + /* + * the buddy cache inode stores the block bitmap + * and buddy information in consecutive blocks. + * So for each group we need two blocks. + */ + block = group * 2; + pnum = block / blocks_per_page; + first_group = pnum * blocks_per_page / 2; + /* release locks on all the groups */ + for (i = 0; i < locked_group; i++) { + + grp = ext4_get_group_info(sb, first_group + i); + /* take all groups write allocation + * semaphore. This make sure there is + * no block allocation going on in any + * of that groups + */ + up_write(&grp->alloc_sem); + } + +} + +/* * Locking note: This routine calls ext4_mb_init_cache(), which takes the * block group lock of all groups for this page; do not hold the BG lock when * calling this routine! @@ -1923,84 +2002,6 @@ static int ext4_mb_good_group(struct ext4_allocation_context *ac, return 0; } -/* - * lock the group_info alloc_sem of all the groups - * belonging to the same buddy cache page. This - * make sure other parallel operation on the buddy - * cache doesn't happen whild holding the buddy cache - * lock - */ -int ext4_mb_get_buddy_cache_lock(struct super_block *sb, ext4_group_t group) -{ - int i; - int block, pnum; - int blocks_per_page; - int groups_per_page; - ext4_group_t ngroups = ext4_get_groups_count(sb); - ext4_group_t first_group; - struct ext4_group_info *grp; - - blocks_per_page = PAGE_CACHE_SIZE / sb->s_blocksize; - /* - * the buddy cache inode stores the block bitmap - * and buddy information in consecutive blocks. - * So for each group we need two blocks. - */ - block = group * 2; - pnum = block / blocks_per_page; - first_group = pnum * blocks_per_page / 2; - - groups_per_page = blocks_per_page >> 1; - if (groups_per_page == 0) - groups_per_page = 1; - /* read all groups the page covers into the cache */ - for (i = 0; i < groups_per_page; i++) { - - if ((first_group + i) >= ngroups) - break; - grp = ext4_get_group_info(sb, first_group + i); - /* take all groups write allocation - * semaphore. This make sure there is - * no block allocation going on in any - * of that groups - */ - down_write_nested(&grp->alloc_sem, i); - } - return i; -} - -void ext4_mb_put_buddy_cache_lock(struct super_block *sb, - ext4_group_t group, int locked_group) -{ - int i; - int block, pnum; - int blocks_per_page; - ext4_group_t first_group; - struct ext4_group_info *grp; - - blocks_per_page = PAGE_CACHE_SIZE / sb->s_blocksize; - /* - * the buddy cache inode stores the block bitmap - * and buddy information in consecutive blocks. - * So for each group we need two blocks. - */ - block = group * 2; - pnum = block / blocks_per_page; - first_group = pnum * blocks_per_page / 2; - /* release locks on all the groups */ - for (i = 0; i < locked_group; i++) { - - grp = ext4_get_group_info(sb, first_group + i); - /* take all groups write allocation - * semaphore. This make sure there is - * no block allocation going on in any - * of that groups - */ - up_write(&grp->alloc_sem); - } - -} - static noinline_for_stack int ext4_mb_regular_allocator(struct ext4_allocation_context *ac) { |
