Btrfs: Don't use kmap_atomic(..., KM_IRQ0) during checksum verifies

[safe/jmp/linux-2.6] / fs / btrfs / disk-io.h

diff --git a/fs/btrfs/disk-io.h b/fs/btrfs/disk-io.h
index 717e948..c0ff404 100644 (file)
--- a/fs/btrfs/disk-io.h
+++ b/fs/btrfs/disk-io.h
@@ -19,8 +19,20 @@
 #ifndef __DISKIO__
 #define __DISKIO__
 
-#define BTRFS_SUPER_INFO_OFFSET (16 * 1024)
+#define BTRFS_SUPER_INFO_OFFSET (64 * 1024)
 #define BTRFS_SUPER_INFO_SIZE 4096
+
+#define BTRFS_SUPER_MIRROR_MAX  3
+#define BTRFS_SUPER_MIRROR_SHIFT 12
+
+static inline u64 btrfs_sb_offset(int mirror)
+{
+       u64 start = 16 * 1024;
+       if (mirror)
+               return start << (BTRFS_SUPER_MIRROR_SHIFT * mirror);
+       return BTRFS_SUPER_INFO_OFFSET;
+}
+
 struct btrfs_device;
 struct btrfs_fs_devices;
 
@@ -37,7 +49,8 @@ struct btrfs_root *open_ctree(struct super_block *sb,
                              char *options);
 int close_ctree(struct btrfs_root *root);
 int write_ctree_super(struct btrfs_trans_handle *trans,
-                     struct btrfs_root *root);
+                     struct btrfs_root *root, int max_mirrors);
+struct buffer_head *btrfs_read_dev_super(struct block_device *bdev);
 int btrfs_commit_super(struct btrfs_root *root);
 struct extent_buffer *btrfs_find_tree_block(struct btrfs_root *root,
                                            u64 bytenr, u32 blocksize);