Btrfs: Add support for mirroring across drives

Signed-off-by: Chris Mason <chris.mason@oracle.com>

1 files changed, 6 insertions, 5 deletions

diff --git a/fs/btrfs/volumes.h b/fs/btrfs/volumes.h
index 12f297eb0559..35dec3efd78c 100644
--- a/fs/btrfs/volumes.h
+++ b/fs/btrfs/volumes.h
@@ -18,12 +18,16 @@
 
 #ifndef __BTRFS_VOLUMES_
 #define __BTRFS_VOLUMES_
+
 struct btrfs_device {
         struct list_head dev_list;
         struct btrfs_root *dev_root;
+        spinlock_t io_lock;
 
         struct block_device *bdev;
 
+        u64 total_ios;
+
         char *name;
 
         /* the internal btrfs device id */
@@ -68,9 +72,9 @@ struct btrfs_fs_devices {
 int btrfs_alloc_dev_extent(struct btrfs_trans_handle *trans,
                            struct btrfs_device *device,
                            u64 owner, u64 num_bytes, u64 *start);
-int btrfs_map_block(struct btrfs_mapping_tree *map_tree,
+int btrfs_map_block(struct btrfs_mapping_tree *map_tree, int rw, int stripe_nr,
                     u64 logical, u64 *phys, u64 *length,
-                    struct btrfs_device **dev);
+                    struct btrfs_device **dev, int *total_stripes);
 int btrfs_read_sys_array(struct btrfs_root *root);
 int btrfs_read_chunk_tree(struct btrfs_root *root);
 int btrfs_alloc_chunk(struct btrfs_trans_handle *trans,
@@ -80,9 +84,6 @@ void btrfs_mapping_init(struct btrfs_mapping_tree *tree);
 void btrfs_mapping_tree_free(struct btrfs_mapping_tree *tree);
 int btrfs_map_bio(struct btrfs_root *root, int rw, struct bio *bio);
 int btrfs_read_super_device(struct btrfs_root *root, struct extent_buffer *buf);
-int btrfs_map_block(struct btrfs_mapping_tree *map_tree,
-                    u64 logical, u64 *phys, u64 *length,
-                    struct btrfs_device **dev);
 int btrfs_open_devices(struct btrfs_fs_devices *fs_devices,
                        int flags, void *holder);
 int btrfs_scan_one_device(const char *path, int flags, void *holder,