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author | Chris Mason <chris.mason@oracle.com> | 2008-09-05 20:13:11 (GMT) |
---|---|---|
committer | Chris Mason <chris.mason@oracle.com> | 2008-09-25 15:04:07 (GMT) |
commit | e02119d5a7b4396c5a872582fddc8bd6d305a70a (patch) | |
tree | 825efe2a79dbca8d61256183f3526a5b5dc40dc6 /fs/btrfs/extent-tree.c | |
parent | a1b32a5932cfac7c38b442582285f3da2a09dfd8 (diff) | |
download | linux-fsl-qoriq-e02119d5a7b4396c5a872582fddc8bd6d305a70a.tar.xz |
Btrfs: Add a write ahead tree log to optimize synchronous operations
File syncs and directory syncs are optimized by copying their
items into a special (copy-on-write) log tree. There is one log tree per
subvolume and the btrfs super block points to a tree of log tree roots.
After a crash, items are copied out of the log tree and back into the
subvolume. See tree-log.c for all the details.
Signed-off-by: Chris Mason <chris.mason@oracle.com>
Diffstat (limited to 'fs/btrfs/extent-tree.c')
-rw-r--r-- | fs/btrfs/extent-tree.c | 93 |
1 files changed, 75 insertions, 18 deletions
diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c index e63b3b4..646b914 100644 --- a/fs/btrfs/extent-tree.c +++ b/fs/btrfs/extent-tree.c @@ -496,6 +496,23 @@ static int match_extent_ref(struct extent_buffer *leaf, return ret == 0; } +/* simple helper to search for an existing extent at a given offset */ +int btrfs_lookup_extent(struct btrfs_root *root, struct btrfs_path *path, + u64 start, u64 len) +{ + int ret; + struct btrfs_key key; + + maybe_lock_mutex(root); + key.objectid = start; + key.offset = len; + btrfs_set_key_type(&key, BTRFS_EXTENT_ITEM_KEY); + ret = btrfs_search_slot(NULL, root->fs_info->extent_root, &key, path, + 0, 0); + maybe_unlock_mutex(root); + return ret; +} + static int noinline lookup_extent_backref(struct btrfs_trans_handle *trans, struct btrfs_root *root, struct btrfs_path *path, u64 bytenr, @@ -1409,7 +1426,7 @@ static u64 first_logical_byte(struct btrfs_root *root, u64 search_start) } -static int update_pinned_extents(struct btrfs_root *root, +int btrfs_update_pinned_extents(struct btrfs_root *root, u64 bytenr, u64 num, int pin) { u64 len; @@ -1492,7 +1509,7 @@ int btrfs_finish_extent_commit(struct btrfs_trans_handle *trans, EXTENT_DIRTY); if (ret) break; - update_pinned_extents(root, start, end + 1 - start, 0); + btrfs_update_pinned_extents(root, start, end + 1 - start, 0); clear_extent_dirty(unpin, start, end, GFP_NOFS); set_extent_dirty(free_space_cache, start, end, GFP_NOFS); if (need_resched()) { @@ -1538,14 +1555,11 @@ static int finish_current_insert(struct btrfs_trans_handle *trans, clear_extent_bits(&info->extent_ins, start, end, EXTENT_LOCKED, GFP_NOFS); - eb = btrfs_find_tree_block(extent_root, ins.objectid, + eb = btrfs_find_create_tree_block(extent_root, ins.objectid, ins.offset); - if (!btrfs_buffer_uptodate(eb, trans->transid)) { - mutex_unlock(&extent_root->fs_info->alloc_mutex); + if (!btrfs_buffer_uptodate(eb, trans->transid)) btrfs_read_buffer(eb, trans->transid); - mutex_lock(&extent_root->fs_info->alloc_mutex); - } btrfs_tree_lock(eb); level = btrfs_header_level(eb); @@ -1585,13 +1599,20 @@ static int pin_down_bytes(struct btrfs_root *root, u64 bytenr, u32 num_bytes, struct extent_buffer *buf; buf = btrfs_find_tree_block(root, bytenr, num_bytes); if (buf) { + /* we can reuse a block if it hasn't been written + * and it is from this transaction. We can't + * reuse anything from the tree log root because + * it has tiny sub-transactions. + */ if (btrfs_buffer_uptodate(buf, 0) && btrfs_try_tree_lock(buf)) { u64 transid = root->fs_info->running_transaction->transid; u64 header_transid = btrfs_header_generation(buf); - if (header_transid == transid && + if (btrfs_header_owner(buf) != + BTRFS_TREE_LOG_OBJECTID && + header_transid == transid && !btrfs_header_flag(buf, BTRFS_HEADER_FLAG_WRITTEN)) { clean_tree_block(NULL, root, buf); @@ -1603,7 +1624,7 @@ static int pin_down_bytes(struct btrfs_root *root, u64 bytenr, u32 num_bytes, } free_extent_buffer(buf); } - update_pinned_extents(root, bytenr, num_bytes, 1); + btrfs_update_pinned_extents(root, bytenr, num_bytes, 1); } else { set_extent_bits(&root->fs_info->pending_del, bytenr, bytenr + num_bytes - 1, @@ -1801,7 +1822,7 @@ static int del_pending_extents(struct btrfs_trans_handle *trans, struct GFP_NOFS); if (!test_range_bit(&extent_root->fs_info->extent_ins, start, end, EXTENT_LOCKED, 0)) { - update_pinned_extents(extent_root, start, + btrfs_update_pinned_extents(extent_root, start, end + 1 - start, 1); ret = __free_extent(trans, extent_root, start, end + 1 - start, @@ -1919,6 +1940,12 @@ static int noinline find_free_extent(struct btrfs_trans_handle *trans, if ((data & BTRFS_BLOCK_GROUP_DATA) && btrfs_test_opt(root, SSD)) { last_ptr = &root->fs_info->last_data_alloc; } + if (root->root_key.objectid == BTRFS_TREE_LOG_OBJECTID) { + last_ptr = &root->fs_info->last_log_alloc; + if (!last_ptr == 0 && root->fs_info->last_alloc) { + *last_ptr = root->fs_info->last_alloc + empty_cluster; + } + } if (last_ptr) { if (*last_ptr) @@ -2268,6 +2295,35 @@ int btrfs_alloc_reserved_extent(struct btrfs_trans_handle *trans, maybe_unlock_mutex(root); return ret; } + +/* + * this is used by the tree logging recovery code. It records that + * an extent has been allocated and makes sure to clear the free + * space cache bits as well + */ +int btrfs_alloc_logged_extent(struct btrfs_trans_handle *trans, + struct btrfs_root *root, + u64 root_objectid, u64 ref_generation, + u64 owner, u64 owner_offset, + struct btrfs_key *ins) +{ + int ret; + struct btrfs_block_group_cache *block_group; + + maybe_lock_mutex(root); + block_group = btrfs_lookup_block_group(root->fs_info, ins->objectid); + cache_block_group(root, block_group); + + clear_extent_dirty(&root->fs_info->free_space_cache, + ins->objectid, ins->objectid + ins->offset - 1, + GFP_NOFS); + ret = __btrfs_alloc_reserved_extent(trans, root, root_objectid, + ref_generation, owner, + owner_offset, ins); + maybe_unlock_mutex(root); + return ret; +} + /* * finds a free extent and does all the dirty work required for allocation * returns the key for the extent through ins, and a tree buffer for @@ -2350,9 +2406,8 @@ struct extent_buffer *btrfs_alloc_free_block(struct btrfs_trans_handle *trans, return buf; } -static int noinline drop_leaf_ref_no_cache(struct btrfs_trans_handle *trans, - struct btrfs_root *root, - struct extent_buffer *leaf) +int btrfs_drop_leaf_ref(struct btrfs_trans_handle *trans, + struct btrfs_root *root, struct extent_buffer *leaf) { u64 leaf_owner; u64 leaf_generation; @@ -2402,9 +2457,9 @@ static int noinline drop_leaf_ref_no_cache(struct btrfs_trans_handle *trans, return 0; } -static int noinline drop_leaf_ref(struct btrfs_trans_handle *trans, - struct btrfs_root *root, - struct btrfs_leaf_ref *ref) +static int noinline cache_drop_leaf_ref(struct btrfs_trans_handle *trans, + struct btrfs_root *root, + struct btrfs_leaf_ref *ref) { int i; int ret; @@ -2512,7 +2567,7 @@ static int noinline walk_down_tree(struct btrfs_trans_handle *trans, btrfs_header_nritems(cur)) break; if (*level == 0) { - ret = drop_leaf_ref_no_cache(trans, root, cur); + ret = btrfs_drop_leaf_ref(trans, root, cur); BUG_ON(ret); break; } @@ -2552,7 +2607,7 @@ static int noinline walk_down_tree(struct btrfs_trans_handle *trans, btrfs_node_key_to_cpu(cur, &key, path->slots[*level]); ref = btrfs_lookup_leaf_ref(root, bytenr); if (ref) { - ret = drop_leaf_ref(trans, root, ref); + ret = cache_drop_leaf_ref(trans, root, ref); BUG_ON(ret); btrfs_remove_leaf_ref(root, ref); btrfs_free_leaf_ref(root, ref); @@ -3628,6 +3683,8 @@ int btrfs_make_block_group(struct btrfs_trans_handle *trans, extent_root = root->fs_info->extent_root; block_group_cache = &root->fs_info->block_group_cache; + root->fs_info->last_trans_new_blockgroup = trans->transid; + cache = kzalloc(sizeof(*cache), GFP_NOFS); BUG_ON(!cache); cache->key.objectid = chunk_offset; |