diff options
| -rw-r--r-- | fs/buffer.c | 23 |
1 files changed, 19 insertions, 4 deletions
diff --git a/fs/buffer.c b/fs/buffer.c index 6f0bddddcf4..3ebccf4aa7e 100644 --- a/fs/buffer.c +++ b/fs/buffer.c @@ -678,7 +678,7 @@ void mark_buffer_dirty_inode(struct buffer_head *bh, struct inode *inode) } else { BUG_ON(mapping->assoc_mapping != buffer_mapping); } - if (list_empty(&bh->b_assoc_buffers)) { + if (!bh->b_assoc_map) { spin_lock(&buffer_mapping->private_lock); list_move_tail(&bh->b_assoc_buffers, &mapping->private_list); @@ -794,6 +794,7 @@ static int fsync_buffers_list(spinlock_t *lock, struct list_head *list) { struct buffer_head *bh; struct list_head tmp; + struct address_space *mapping; int err = 0, err2; INIT_LIST_HEAD(&tmp); @@ -801,9 +802,14 @@ static int fsync_buffers_list(spinlock_t *lock, struct list_head *list) spin_lock(lock); while (!list_empty(list)) { bh = BH_ENTRY(list->next); + mapping = bh->b_assoc_map; __remove_assoc_queue(bh); + /* Avoid race with mark_buffer_dirty_inode() which does + * a lockless check and we rely on seeing the dirty bit */ + smp_mb(); if (buffer_dirty(bh) || buffer_locked(bh)) { list_add(&bh->b_assoc_buffers, &tmp); + bh->b_assoc_map = mapping; if (buffer_dirty(bh)) { get_bh(bh); spin_unlock(lock); @@ -822,8 +828,17 @@ static int fsync_buffers_list(spinlock_t *lock, struct list_head *list) while (!list_empty(&tmp)) { bh = BH_ENTRY(tmp.prev); - list_del_init(&bh->b_assoc_buffers); get_bh(bh); + mapping = bh->b_assoc_map; + __remove_assoc_queue(bh); + /* Avoid race with mark_buffer_dirty_inode() which does + * a lockless check and we rely on seeing the dirty bit */ + smp_mb(); + if (buffer_dirty(bh)) { + list_add(&bh->b_assoc_buffers, + &bh->b_assoc_map->private_list); + bh->b_assoc_map = mapping; + } spin_unlock(lock); wait_on_buffer(bh); if (!buffer_uptodate(bh)) @@ -1195,7 +1210,7 @@ void __brelse(struct buffer_head * buf) void __bforget(struct buffer_head *bh) { clear_buffer_dirty(bh); - if (!list_empty(&bh->b_assoc_buffers)) { + if (bh->b_assoc_map) { struct address_space *buffer_mapping = bh->b_page->mapping; spin_lock(&buffer_mapping->private_lock); @@ -3022,7 +3037,7 @@ drop_buffers(struct page *page, struct buffer_head **buffers_to_free) do { struct buffer_head *next = bh->b_this_page; - if (!list_empty(&bh->b_assoc_buffers)) + if (bh->b_assoc_map) __remove_assoc_queue(bh); bh = next; } while (bh != head); |