X-Git-Url: http://pilppa.org/gitweb/gitweb.cgi?a=blobdiff_plain;f=fs%2Fbuffer.c;h=7d51e649b19a7d8f84061186fbd84326420f44f8;hb=308c05e35e3517d19bb67a7e97772235c9e15cd7;hp=826baf4f04bc738fdfea27f6652bc3c0bfe9969d;hpb=6e5565f949af1322f8f3d3f43d044645ae448499;p=linux-2.6-omap-h63xx.git

diff --git a/fs/buffer.c b/fs/buffer.c
index 826baf4f04b..7d51e649b19 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);
@@ -360,16 +360,19 @@ void invalidate_bdev(struct block_device *bdev)
  */
 static void free_more_memory(void)
 {
-	struct zone **zones;
-	pg_data_t *pgdat;
+	struct zone *zone;
+	int nid;
 
 	wakeup_pdflush(1024);
 	yield();
 
-	for_each_online_pgdat(pgdat) {
-		zones = pgdat->node_zonelists[gfp_zone(GFP_NOFS)].zones;
-		if (*zones)
-			try_to_free_pages(zones, 0, GFP_NOFS);
+	for_each_online_node(nid) {
+		(void)first_zones_zonelist(node_zonelist(nid, GFP_NOFS),
+						gfp_zone(GFP_NOFS), NULL,
+						&zone);
+		if (zone)
+			try_to_free_pages(node_zonelist(nid, GFP_NOFS), 0,
+						GFP_NOFS);
 	}
 }
 
@@ -627,8 +630,7 @@ repeat:
 }
 
 /**
- * sync_mapping_buffers - write out and wait upon a mapping's "associated"
- *                        buffers
+ * sync_mapping_buffers - write out & wait upon a mapping's "associated" buffers
  * @mapping: the mapping which wants those buffers written
  *
  * Starts I/O against the buffers at mapping->private_list, and waits upon
@@ -678,7 +680,7 @@ 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 +796,7 @@ 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 +804,14 @@ 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 +830,17 @@ 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,
+				 &mapping->private_list);
+			bh->b_assoc_map = mapping;
+		}
 		spin_unlock(lock);
 		wait_on_buffer(bh);
 		if (!buffer_uptodate(bh))
@@ -1164,10 +1181,23 @@ __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))
+
+	/*
+	 * Very *carefully* optimize the it-is-already-dirty case.
+	 *
+	 * Don't let the final "is it dirty" escape to before we
+	 * perhaps modified the buffer.
+	 */
+	if (buffer_dirty(bh)) {
+		smp_mb();
+		if (buffer_dirty(bh))
+			return;
+	}
+
+	if (!test_set_buffer_dirty(bh))
 		__set_page_dirty(bh->b_page, page_mapping(bh->b_page), 0);
 }
 
@@ -1195,7 +1225,7 @@ 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 +1466,7 @@ 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)
@@ -2549,14 +2580,13 @@ int nobh_write_end(struct file *file, struct address_space *mapping,
 	struct inode *inode = page->mapping->host;
 	struct buffer_head *head = fsdata;
 	struct buffer_head *bh;
+	BUG_ON(fsdata != NULL && page_has_buffers(page));
 
-	if (!PageMappedToDisk(page)) {
-		if (unlikely(copied < len) && !page_has_buffers(page))
-			attach_nobh_buffers(page, head);
-		if (page_has_buffers(page))
-			return generic_write_end(file, mapping, pos, len,
-						copied, page, fsdata);
-	}
+	if (unlikely(copied < len) && !page_has_buffers(page))
+		attach_nobh_buffers(page, head);
+	if (page_has_buffers(page))
+		return generic_write_end(file, mapping, pos, len,
+					copied, page, fsdata);
 
 	SetPageUptodate(page);
 	set_page_dirty(page);
@@ -3021,7 +3051,7 @@ 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);
@@ -3153,8 +3183,7 @@ static void recalc_bh_state(void)
 	
 struct buffer_head *alloc_buffer_head(gfp_t gfp_flags)
 {
-	struct buffer_head *ret = kmem_cache_alloc(bh_cachep,
-				set_migrateflags(gfp_flags, __GFP_RECLAIMABLE));
+	struct buffer_head *ret = kmem_cache_alloc(bh_cachep, gfp_flags);
 	if (ret) {
 		INIT_LIST_HEAD(&ret->b_assoc_buffers);
 		get_cpu_var(bh_accounting).nr++;
@@ -3198,7 +3227,7 @@ static int buffer_cpu_notify(struct notifier_block *self,
 }
 
 /**
- * bh_uptodate_or_lock: Test whether the buffer is uptodate
+ * bh_uptodate_or_lock - Test whether the buffer is uptodate
  * @bh: struct buffer_head
  *
  * Return true if the buffer is up-to-date and false,
@@ -3217,7 +3246,7 @@ int bh_uptodate_or_lock(struct buffer_head *bh)
 EXPORT_SYMBOL(bh_uptodate_or_lock);
 
 /**
- * bh_submit_read: Submit a locked buffer for reading
+ * bh_submit_read - Submit a locked buffer for reading
  * @bh: struct buffer_head
  *
  * Returns zero on success and -EIO on error.