diff options
Diffstat (limited to 'fs/btrfs/defrag.c')
| -rw-r--r-- | fs/btrfs/defrag.c | 152 |
1 files changed, 148 insertions, 4 deletions
diff --git a/fs/btrfs/defrag.c b/fs/btrfs/defrag.c index f2ff4cbe8656..5244561e2016 100644 --- a/fs/btrfs/defrag.c +++ b/fs/btrfs/defrag.c @@ -338,13 +338,118 @@ int btrfs_run_defrag_inodes(struct btrfs_fs_info *fs_info) } /* + * Check if two blocks addresses are close, used by defrag. + */ +static bool close_blocks(u64 blocknr, u64 other, u32 blocksize) +{ + if (blocknr < other && other - (blocknr + blocksize) < SZ_32K) + return true; + if (blocknr > other && blocknr - (other + blocksize) < SZ_32K) + return true; + return false; +} + +/* + * Go through all the leaves pointed to by a node and reallocate them so that + * disk order is close to key order. + */ +static int btrfs_realloc_node(struct btrfs_trans_handle *trans, + struct btrfs_root *root, + struct extent_buffer *parent, + int start_slot, u64 *last_ret, + struct btrfs_key *progress) +{ + struct btrfs_fs_info *fs_info = root->fs_info; + const u32 blocksize = fs_info->nodesize; + const int end_slot = btrfs_header_nritems(parent) - 1; + u64 search_start = *last_ret; + u64 last_block = 0; + int ret = 0; + bool progress_passed = false; + + /* + * COWing must happen through a running transaction, which always + * matches the current fs generation (it's a transaction with a state + * less than TRANS_STATE_UNBLOCKED). If it doesn't, then turn the fs + * into error state to prevent the commit of any transaction. + */ + if (unlikely(trans->transaction != fs_info->running_transaction || + trans->transid != fs_info->generation)) { + btrfs_abort_transaction(trans, -EUCLEAN); + btrfs_crit(fs_info, +"unexpected transaction when attempting to reallocate parent %llu for root %llu, transaction %llu running transaction %llu fs generation %llu", + parent->start, btrfs_root_id(root), trans->transid, + fs_info->running_transaction->transid, + fs_info->generation); + return -EUCLEAN; + } + + if (btrfs_header_nritems(parent) <= 1) + return 0; + + for (int i = start_slot; i <= end_slot; i++) { + struct extent_buffer *cur; + struct btrfs_disk_key disk_key; + u64 blocknr; + u64 other; + bool close = true; + + btrfs_node_key(parent, &disk_key, i); + if (!progress_passed && btrfs_comp_keys(&disk_key, progress) < 0) + continue; + + progress_passed = true; + blocknr = btrfs_node_blockptr(parent, i); + if (last_block == 0) + last_block = blocknr; + + if (i > 0) { + other = btrfs_node_blockptr(parent, i - 1); + close = close_blocks(blocknr, other, blocksize); + } + if (!close && i < end_slot) { + other = btrfs_node_blockptr(parent, i + 1); + close = close_blocks(blocknr, other, blocksize); + } + if (close) { + last_block = blocknr; + continue; + } + + cur = btrfs_read_node_slot(parent, i); + if (IS_ERR(cur)) + return PTR_ERR(cur); + if (search_start == 0) + search_start = last_block; + + btrfs_tree_lock(cur); + ret = btrfs_force_cow_block(trans, root, cur, parent, i, + &cur, search_start, + min(16 * blocksize, + (end_slot - i) * blocksize), + BTRFS_NESTING_COW); + if (ret) { + btrfs_tree_unlock(cur); + free_extent_buffer(cur); + break; + } + search_start = cur->start; + last_block = cur->start; + *last_ret = search_start; + btrfs_tree_unlock(cur); + free_extent_buffer(cur); + } + return ret; +} + +/* * Defrag all the leaves in a given btree. * Read all the leaves and try to get key order to * better reflect disk order */ -int btrfs_defrag_leaves(struct btrfs_trans_handle *trans, - struct btrfs_root *root) +static int btrfs_defrag_leaves(struct btrfs_trans_handle *trans, + struct btrfs_root *root) { struct btrfs_path *path = NULL; struct btrfs_key key; @@ -461,6 +566,45 @@ done: } /* + * Defrag a given btree. Every leaf in the btree is read and defragmented. + */ +int btrfs_defrag_root(struct btrfs_root *root) +{ + struct btrfs_fs_info *fs_info = root->fs_info; + int ret; + + if (test_and_set_bit(BTRFS_ROOT_DEFRAG_RUNNING, &root->state)) + return 0; + + while (1) { + struct btrfs_trans_handle *trans; + + trans = btrfs_start_transaction(root, 0); + if (IS_ERR(trans)) { + ret = PTR_ERR(trans); + break; + } + + ret = btrfs_defrag_leaves(trans, root); + + btrfs_end_transaction(trans); + btrfs_btree_balance_dirty(fs_info); + cond_resched(); + + if (btrfs_fs_closing(fs_info) || ret != -EAGAIN) + break; + + if (btrfs_defrag_cancelled(fs_info)) { + btrfs_debug(fs_info, "defrag_root cancelled"); + ret = -EAGAIN; + break; + } + } + clear_bit(BTRFS_ROOT_DEFRAG_RUNNING, &root->state); + return ret; +} + +/* * Defrag specific helper to get an extent map. * * Differences between this and btrfs_get_extent() are: @@ -891,8 +1035,8 @@ static int defrag_collect_targets(struct btrfs_inode *inode, * very likely resulting in a larger extent after writeback is * triggered (except in a case of free space fragmentation). */ - if (test_range_bit(&inode->io_tree, cur, cur + range_len - 1, - EXTENT_DELALLOC, 0, NULL)) + if (test_range_bit_exists(&inode->io_tree, cur, cur + range_len - 1, + EXTENT_DELALLOC)) goto next; /* |