Btrfs: early support for multiple devices
Signed-off-by: Chris Mason <chris.mason@oracle.com>
diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h
index 3f3a23f..01310de 100644
--- a/fs/btrfs/ctree.h
+++ b/fs/btrfs/ctree.h
@@ -13,10 +13,11 @@
#define BTRFS_MAGIC "_BtRfS_M"
#define BTRFS_ROOT_TREE_OBJECTID 1ULL
-#define BTRFS_EXTENT_TREE_OBJECTID 2ULL
-#define BTRFS_FS_TREE_OBJECTID 3ULL
-#define BTRFS_ROOT_TREE_DIR_OBJECTID 4ULL
-#define BTRFS_FIRST_FREE_OBJECTID 5ULL
+#define BTRFS_DEV_TREE_OBJECTID 2ULL
+#define BTRFS_EXTENT_TREE_OBJECTID 3ULL
+#define BTRFS_FS_TREE_OBJECTID 4ULL
+#define BTRFS_ROOT_TREE_DIR_OBJECTID 5ULL
+#define BTRFS_FIRST_FREE_OBJECTID 6ULL
/*
* we can actually store much bigger names, but lets not confuse the rest
@@ -90,6 +91,10 @@
__le64 total_blocks;
__le64 blocks_used;
__le64 root_dir_objectid;
+ /* fields below here vary with the underlying disk */
+ __le64 device_block_start;
+ __le64 device_num_blocks;
+ __le64 device_root;
} __attribute__ ((__packed__));
/*
@@ -223,10 +228,15 @@
u8 csum[BTRFS_CSUM_SIZE];
} __attribute__ ((__packed__));
+struct btrfs_device_item {
+ __le16 pathlen;
+} __attribute__ ((__packed__));
+
struct crypto_hash;
struct btrfs_fs_info {
struct btrfs_root *extent_root;
struct btrfs_root *tree_root;
+ struct btrfs_root *dev_root;
struct btrfs_key current_insert;
struct btrfs_key last_insert;
struct radix_tree_root fs_roots_radix;
@@ -313,10 +323,15 @@
#define BTRFS_EXTENT_ITEM_KEY 8
/*
+ * dev items list the devices that make up the FS
+ */
+#define BTRFS_DEV_ITEM_KEY 9
+
+/*
* string items are for debugging. They just store a short string of
* data in the FS
*/
-#define BTRFS_STRING_ITEM_KEY 9
+#define BTRFS_STRING_ITEM_KEY 10
static inline u64 btrfs_inode_generation(struct btrfs_inode_item *i)
{
@@ -782,6 +797,40 @@
s->root_dir_objectid = cpu_to_le64(val);
}
+static inline u64 btrfs_super_device_block_start(struct btrfs_super_block *s)
+{
+ return le64_to_cpu(s->device_block_start);
+}
+
+static inline void btrfs_set_super_device_block_start(struct btrfs_super_block
+ *s, u64 val)
+{
+ s->device_block_start = cpu_to_le64(val);
+}
+
+static inline u64 btrfs_super_device_num_blocks(struct btrfs_super_block *s)
+{
+ return le64_to_cpu(s->device_num_blocks);
+}
+
+static inline void btrfs_set_super_device_num_blocks(struct btrfs_super_block
+ *s, u64 val)
+{
+ s->device_num_blocks = cpu_to_le64(val);
+}
+
+static inline u64 btrfs_super_device_root(struct btrfs_super_block *s)
+{
+ return le64_to_cpu(s->device_root);
+}
+
+static inline void btrfs_set_super_device_root(struct btrfs_super_block
+ *s, u64 val)
+{
+ s->device_root = cpu_to_le64(val);
+}
+
+
static inline u8 *btrfs_leaf_data(struct btrfs_leaf *l)
{
return (u8 *)l->items;
@@ -849,6 +898,17 @@
e->num_blocks = cpu_to_le64(val);
}
+static inline u16 btrfs_device_pathlen(struct btrfs_device_item *d)
+{
+ return le16_to_cpu(d->pathlen);
+}
+
+static inline void btrfs_set_device_pathlen(struct btrfs_device_item *d,
+ u16 val)
+{
+ d->pathlen = cpu_to_le16(val);
+}
+
static inline struct btrfs_root *btrfs_sb(struct super_block *sb)
{
return sb->s_fs_info;