Merge branch 'for-linus' of git://git.linaro.org/people/rmk/linux-arm

[linux.git] / fs / ext4 / balloc.c

diff --git a/fs/ext4/balloc.c b/fs/ext4/balloc.c
index f9e2cd8cf711d2f43a74f5a5f4cc830604cd82d9..4bbd07a6fa189f6ab3f87825e3b94c061972c666 100644 (file)
--- a/fs/ext4/balloc.c
+++ b/fs/ext4/balloc.c
@@ -336,10 +336,10 @@ err_out:
  * Return buffer_head on success or NULL in case of failure.
  */
 struct buffer_head *
-ext4_read_block_bitmap(struct super_block *sb, ext4_group_t block_group)
+ext4_read_block_bitmap_nowait(struct super_block *sb, ext4_group_t block_group)
 {
        struct ext4_group_desc *desc;
-       struct buffer_head *bh = NULL;
+       struct buffer_head *bh;
        ext4_fsblk_t bitmap_blk;
 
        desc = ext4_get_group_desc(sb, block_group, NULL);
@@ -348,9 +348,9 @@ ext4_read_block_bitmap(struct super_block *sb, ext4_group_t block_group)
        bitmap_blk = ext4_block_bitmap(sb, desc);
        bh = sb_getblk(sb, bitmap_blk);
        if (unlikely(!bh)) {
-               ext4_error(sb, "Cannot read block bitmap - "
-                           "block_group = %u, block_bitmap = %llu",
-                           block_group, bitmap_blk);
+               ext4_error(sb, "Cannot get buffer for block bitmap - "
+                          "block_group = %u, block_bitmap = %llu",
+                          block_group, bitmap_blk);
                return NULL;
        }
 
@@ -382,25 +382,50 @@ ext4_read_block_bitmap(struct super_block *sb, ext4_group_t block_group)
                return bh;
        }
        /*
-        * submit the buffer_head for read. We can
-        * safely mark the bitmap as uptodate now.
-        * We do it here so the bitmap uptodate bit
-        * get set with buffer lock held.
+        * submit the buffer_head for reading
         */
+       set_buffer_new(bh);
        trace_ext4_read_block_bitmap_load(sb, block_group);
-       set_bitmap_uptodate(bh);
-       if (bh_submit_read(bh) < 0) {
-               put_bh(bh);
+       bh->b_end_io = ext4_end_bitmap_read;
+       get_bh(bh);
+       submit_bh(READ, bh);
+       return bh;
+}
+
+/* Returns 0 on success, 1 on error */
+int ext4_wait_block_bitmap(struct super_block *sb, ext4_group_t block_group,
+                          struct buffer_head *bh)
+{
+       struct ext4_group_desc *desc;
+
+       if (!buffer_new(bh))
+               return 0;
+       desc = ext4_get_group_desc(sb, block_group, NULL);
+       if (!desc)
+               return 1;
+       wait_on_buffer(bh);
+       if (!buffer_uptodate(bh)) {
                ext4_error(sb, "Cannot read block bitmap - "
-                           "block_group = %u, block_bitmap = %llu",
-                           block_group, bitmap_blk);
-               return NULL;
+                          "block_group = %u, block_bitmap = %llu",
+                          block_group, (unsigned long long) bh->b_blocknr);
+               return 1;
        }
+       clear_buffer_new(bh);
+       /* Panic or remount fs read-only if block bitmap is invalid */
        ext4_valid_block_bitmap(sb, desc, block_group, bh);
-       /*
-        * file system mounted not to panic on error,
-        * continue with corrupt bitmap
-        */
+       return 0;
+}
+
+struct buffer_head *
+ext4_read_block_bitmap(struct super_block *sb, ext4_group_t block_group)
+{
+       struct buffer_head *bh;
+
+       bh = ext4_read_block_bitmap_nowait(sb, block_group);
+       if (ext4_wait_block_bitmap(sb, block_group, bh)) {
+               put_bh(bh);
+               return NULL;
+       }
        return bh;
 }