From e17cade25ff8074101d653557a78df09c16ca276 Mon Sep 17 00:00:00 2001 From: Chris Mason Date: Tue, 15 Apr 2008 15:41:47 -0400 Subject: Btrfs: Add chunk uuids and update multi-device back references Block headers now store the chunk tree uuid Chunk items records the device uuid for each stripes Device extent items record better back refs to the chunk tree Block groups record better back refs to the chunk tree The chunk tree format has also changed. The objectid of BTRFS_CHUNK_ITEM_KEY used to be the logical offset of the chunk. Now it is a chunk tree id, with the logical offset being stored in the offset field of the key. This allows a single chunk tree to record multiple logical address spaces, upping the number of bytes indexed by a chunk tree from 2^64 to 2^128. Signed-off-by: Chris Mason --- fs/btrfs/ctree.c | 12 ++++++++++++ 1 file changed, 12 insertions(+) (limited to 'fs/btrfs/ctree.c') diff --git a/fs/btrfs/ctree.c b/fs/btrfs/ctree.c index e8bf6c2..618e526 100644 --- a/fs/btrfs/ctree.c +++ b/fs/btrfs/ctree.c @@ -1382,6 +1382,11 @@ static int noinline insert_new_root(struct btrfs_trans_handle *trans, write_extent_buffer(c, root->fs_info->fsid, (unsigned long)btrfs_header_fsid(c), BTRFS_FSID_SIZE); + + write_extent_buffer(c, root->fs_info->chunk_tree_uuid, + (unsigned long)btrfs_header_chunk_tree_uuid(c), + BTRFS_UUID_SIZE); + btrfs_set_node_key(c, &lower_key, 0); btrfs_set_node_blockptr(c, 0, lower->start); lower_gen = btrfs_header_generation(lower); @@ -1513,6 +1518,9 @@ static int split_node(struct btrfs_trans_handle *trans, struct btrfs_root write_extent_buffer(split, root->fs_info->fsid, (unsigned long)btrfs_header_fsid(split), BTRFS_FSID_SIZE); + write_extent_buffer(split, root->fs_info->chunk_tree_uuid, + (unsigned long)btrfs_header_chunk_tree_uuid(split), + BTRFS_UUID_SIZE); mid = (c_nritems + 1) / 2; @@ -2043,6 +2051,10 @@ again: write_extent_buffer(right, root->fs_info->fsid, (unsigned long)btrfs_header_fsid(right), BTRFS_FSID_SIZE); + + write_extent_buffer(right, root->fs_info->chunk_tree_uuid, + (unsigned long)btrfs_header_chunk_tree_uuid(right), + BTRFS_UUID_SIZE); if (mid <= slot) { if (nritems == 1 || leaf_space_used(l, mid, nritems - mid) + space_needed > -- cgit v1.1