X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=blobdiff_plain;f=fs%2Fbuffer.c;h=62cfd17dc5fee6c87a1dbaabe5e01299e89dc5ad;hb=9fddaca2293d768eb21ea115e5eedec7f1c13c1c;hp=b9bb7ad6897b90456332813bc15615741171c9c8;hpb=e7de369050534025b33aab1033358bf47a577e4d;p=linux-2.6

diff --git a/fs/buffer.c b/fs/buffer.c
index b9bb7ad689..62cfd17dc5 100644
--- a/fs/buffer.c
+++ b/fs/buffer.c
@@ -1022,12 +1022,13 @@ try_again:
 
 		bh->b_state = 0;
 		atomic_set(&bh->b_count, 0);
+		bh->b_private = NULL;
 		bh->b_size = size;
 
 		/* Link the buffer to its page */
 		set_bh_page(bh, page, offset);
 
-		bh->b_end_io = NULL;
+		init_buffer(bh, NULL, NULL);
 	}
 	return head;
 /*
@@ -1165,7 +1166,7 @@ failed:
  * some of those buffers may be aliases of filesystem data.
  * grow_dev_page() will go BUG() if this happens.
  */
-static inline int
+static int
 grow_buffers(struct block_device *bdev, sector_t block, int size)
 {
 	struct page *page;
@@ -1391,7 +1392,7 @@ static void bh_lru_install(struct buffer_head *bh)
 /*
  * Look up the bh in this cpu's LRU.  If it's there, move it to the head.
  */
-static inline struct buffer_head *
+static struct buffer_head *
 lookup_bh_lru(struct block_device *bdev, sector_t block, int size)
 {
 	struct buffer_head *ret = NULL;
@@ -1541,7 +1542,7 @@ EXPORT_SYMBOL(set_bh_page);
 /*
  * Called when truncating a buffer on a page completely.
  */
-static inline void discard_buffer(struct buffer_head * bh)
+static void discard_buffer(struct buffer_head * bh)
 {
 	lock_buffer(bh);
 	clear_buffer_dirty(bh);
@@ -2866,22 +2867,22 @@ void ll_rw_block(int rw, int nr, struct buffer_head *bhs[])
 		else if (test_set_buffer_locked(bh))
 			continue;
 
-		get_bh(bh);
 		if (rw == WRITE || rw == SWRITE) {
 			if (test_clear_buffer_dirty(bh)) {
 				bh->b_end_io = end_buffer_write_sync;
+				get_bh(bh);
 				submit_bh(WRITE, bh);
 				continue;
 			}
 		} else {
 			if (!buffer_uptodate(bh)) {
 				bh->b_end_io = end_buffer_read_sync;
+				get_bh(bh);
 				submit_bh(rw, bh);
 				continue;
 			}
 		}
 		unlock_buffer(bh);
-		put_bh(bh);
 	}
 }
 
@@ -3049,6 +3050,66 @@ asmlinkage long sys_bdflush(int func, long data)
 	return 0;
 }
 
+/*
+ * Migration function for pages with buffers. This function can only be used
+ * if the underlying filesystem guarantees that no other references to "page"
+ * exist.
+ */
+#ifdef CONFIG_MIGRATION
+int buffer_migrate_page(struct page *newpage, struct page *page)
+{
+	struct address_space *mapping = page->mapping;
+	struct buffer_head *bh, *head;
+
+	if (!mapping)
+		return -EAGAIN;
+
+	if (!page_has_buffers(page))
+		return migrate_page(newpage, page);
+
+	head = page_buffers(page);
+
+	if (migrate_page_remove_references(newpage, page, 3))
+		return -EAGAIN;
+
+	bh = head;
+	do {
+		get_bh(bh);
+		lock_buffer(bh);
+		bh = bh->b_this_page;
+
+	} while (bh != head);
+
+	ClearPagePrivate(page);
+	set_page_private(newpage, page_private(page));
+	set_page_private(page, 0);
+	put_page(page);
+	get_page(newpage);
+
+	bh = head;
+	do {
+		set_bh_page(bh, newpage, bh_offset(bh));
+		bh = bh->b_this_page;
+
+	} while (bh != head);
+
+	SetPagePrivate(newpage);
+
+	migrate_page_copy(newpage, page);
+
+	bh = head;
+	do {
+		unlock_buffer(bh);
+ 		put_bh(bh);
+		bh = bh->b_this_page;
+
+	} while (bh != head);
+
+	return 0;
+}
+EXPORT_SYMBOL(buffer_migrate_page);
+#endif
+
 /*
  * Buffer-head allocation
  */