Merge branch 'master' of /pub/scm/linux/kernel/git/torvalds/linux-2.6

1 files changed, 23 insertions, 7 deletions

diff --git a/fs/buffer.c b/fs/buffer.c
index 826baf4f04b..3ebccf4aa7e 100644
--- a/fs/buffer.c
+++ b/fs/buffer.c
@@ -67,14 +67,14 @@ static int sync_buffer(void *word)
 	return 0;
 }
 
-void fastcall __lock_buffer(struct buffer_head *bh)
+void __lock_buffer(struct buffer_head *bh)
 {
 	wait_on_bit_lock(&bh->b_state, BH_Lock, sync_buffer,
 							TASK_UNINTERRUPTIBLE);
 }
 EXPORT_SYMBOL(__lock_buffer);
 
-void fastcall unlock_buffer(struct buffer_head *bh)
+void unlock_buffer(struct buffer_head *bh)
 {
 	smp_mb__before_clear_bit();
 	clear_buffer_locked(bh);
@@ -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))
@@ -1164,7 +1179,7 @@ __getblk_slow(struct block_device *bdev, sector_t block, int size)
  * mark_buffer_dirty() is atomic.  It takes bh->b_page->mapping->private_lock,
  * mapping->tree_lock and the global inode_lock.
  */
-void fastcall mark_buffer_dirty(struct buffer_head *bh)
+void mark_buffer_dirty(struct buffer_head *bh)
 {
 	WARN_ON_ONCE(!buffer_uptodate(bh));
 	if (!buffer_dirty(bh) && !test_set_buffer_dirty(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);
@@ -1436,6 +1451,7 @@ void invalidate_bh_lrus(void)
 {
 	on_each_cpu(invalidate_bh_lru, NULL, 1, 1);
 }
+EXPORT_SYMBOL_GPL(invalidate_bh_lrus);
 
 void set_bh_page(struct buffer_head *bh,
 		struct page *page, unsigned long offset)
@@ -3021,7 +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);