From 9036c10208e1fc496cef7692ba66a78699b360dc Mon Sep 17 00:00:00 2001 From: Yan Zheng Date: Thu, 30 Oct 2008 14:19:41 -0400 Subject: Btrfs: update hole handling v2 This patch splits the hole insertion code out of btrfs_setattr into btrfs_cont_expand and updates btrfs_get_extent to properly handle the case that file extent items are not continuous. Signed-off-by: Yan Zheng --- fs/btrfs/inode.c | 189 +++++++++++++++++++++++++++++-------------------------- 1 file changed, 100 insertions(+), 89 deletions(-) (limited to 'fs/btrfs/inode.c') diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c index dd9cd01042b8..8254d6fa6910 100644 --- a/fs/btrfs/inode.c +++ b/fs/btrfs/inode.c @@ -2296,81 +2296,91 @@ out: return ret; } -static int btrfs_setattr(struct dentry *dentry, struct iattr *attr) +int btrfs_cont_expand(struct inode *inode, loff_t size) { - struct inode *inode = dentry->d_inode; + struct btrfs_trans_handle *trans; + struct btrfs_root *root = BTRFS_I(inode)->root; + struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree; + struct extent_map *em; + u64 mask = root->sectorsize - 1; + u64 hole_start = (inode->i_size + mask) & ~mask; + u64 block_end = (size + mask) & ~mask; + u64 last_byte; + u64 cur_offset; + u64 hole_size; int err; - err = inode_change_ok(inode, attr); + if (size <= hole_start) + return 0; + + err = btrfs_check_free_space(root, 1, 0); if (err) return err; - if (S_ISREG(inode->i_mode) && - attr->ia_valid & ATTR_SIZE && attr->ia_size > inode->i_size) { - struct btrfs_trans_handle *trans; - struct btrfs_root *root = BTRFS_I(inode)->root; - struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree; + btrfs_truncate_page(inode->i_mapping, inode->i_size); - u64 mask = root->sectorsize - 1; - u64 hole_start = (inode->i_size + mask) & ~mask; - u64 block_end = (attr->ia_size + mask) & ~mask; - u64 hole_size; - u64 alloc_hint = 0; + while (1) { + struct btrfs_ordered_extent *ordered; + btrfs_wait_ordered_range(inode, hole_start, + block_end - hole_start); + lock_extent(io_tree, hole_start, block_end - 1, GFP_NOFS); + ordered = btrfs_lookup_ordered_extent(inode, hole_start); + if (!ordered) + break; + unlock_extent(io_tree, hole_start, block_end - 1, GFP_NOFS); + btrfs_put_ordered_extent(ordered); + } - if (attr->ia_size <= hole_start) - goto out; + trans = btrfs_start_transaction(root, 1); + btrfs_set_trans_block_group(trans, inode); - err = btrfs_check_free_space(root, 1, 0); - if (err) - goto fail; + cur_offset = hole_start; + while (1) { + em = btrfs_get_extent(inode, NULL, 0, cur_offset, + block_end - cur_offset, 0); + BUG_ON(IS_ERR(em) || !em); + last_byte = min(extent_map_end(em), block_end); + last_byte = (last_byte + mask) & ~mask; + if (test_bit(EXTENT_FLAG_VACANCY, &em->flags)) { + hole_size = last_byte - cur_offset; + err = btrfs_insert_file_extent(trans, root, + inode->i_ino, cur_offset, 0, + 0, hole_size, 0, hole_size, + 0, 0, 0); + btrfs_drop_extent_cache(inode, hole_start, + last_byte - 1, 0); + } + free_extent_map(em); + cur_offset = last_byte; + if (err || cur_offset >= block_end) + break; + } - btrfs_truncate_page(inode->i_mapping, inode->i_size); + btrfs_end_transaction(trans, root); + unlock_extent(io_tree, hole_start, block_end - 1, GFP_NOFS); + return err; +} - hole_size = block_end - hole_start; - while(1) { - struct btrfs_ordered_extent *ordered; - btrfs_wait_ordered_range(inode, hole_start, hole_size); - - lock_extent(io_tree, hole_start, block_end - 1, GFP_NOFS); - ordered = btrfs_lookup_ordered_extent(inode, hole_start); - if (ordered) { - unlock_extent(io_tree, hole_start, - block_end - 1, GFP_NOFS); - btrfs_put_ordered_extent(ordered); - } else { - break; - } - } +static int btrfs_setattr(struct dentry *dentry, struct iattr *attr) +{ + struct inode *inode = dentry->d_inode; + int err; - trans = btrfs_start_transaction(root, 1); - btrfs_set_trans_block_group(trans, inode); - mutex_lock(&BTRFS_I(inode)->extent_mutex); - err = btrfs_drop_extents(trans, root, inode, - hole_start, block_end, hole_start, - &alloc_hint); + err = inode_change_ok(inode, attr); + if (err) + return err; - if (alloc_hint != EXTENT_MAP_INLINE) { - err = btrfs_insert_file_extent(trans, root, - inode->i_ino, - hole_start, 0, 0, - hole_size, 0, hole_size, - 0, 0, 0); - btrfs_drop_extent_cache(inode, hole_start, - (u64)-1, 0); - btrfs_check_file(root, inode); - } - mutex_unlock(&BTRFS_I(inode)->extent_mutex); - btrfs_end_transaction(trans, root); - unlock_extent(io_tree, hole_start, block_end - 1, GFP_NOFS); + if (S_ISREG(inode->i_mode) && + attr->ia_valid & ATTR_SIZE && attr->ia_size > inode->i_size) { + err = btrfs_cont_expand(inode, attr->ia_size); if (err) return err; } -out: + err = inode_setattr(inode, attr); if (!err && ((attr->ia_valid & ATTR_MODE))) err = btrfs_acl_chmod(inode); -fail: return err; } @@ -3456,27 +3466,44 @@ again: if (found_type == BTRFS_FILE_EXTENT_REG) { extent_end = extent_start + btrfs_file_extent_num_bytes(leaf, item); - err = 0; - if (start < extent_start || start >= extent_end) { - em->start = start; - if (start < extent_start) { - if (start + len <= extent_start) - goto not_found; - em->len = extent_end - extent_start; - } else { - em->len = len; + } else if (found_type == BTRFS_FILE_EXTENT_INLINE) { + size_t size; + size = btrfs_file_extent_inline_len(leaf, item); + extent_end = (extent_start + size + root->sectorsize - 1) & + ~((u64)root->sectorsize - 1); + } + + if (start >= extent_end) { + path->slots[0]++; + if (path->slots[0] >= btrfs_header_nritems(leaf)) { + ret = btrfs_next_leaf(root, path); + if (ret < 0) { + err = ret; + goto out; } - goto not_found_em; + if (ret > 0) + goto not_found; + leaf = path->nodes[0]; } + btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]); + if (found_key.objectid != objectid || + found_key.type != BTRFS_EXTENT_DATA_KEY) + goto not_found; + if (start + len <= found_key.offset) + goto not_found; + em->start = start; + em->len = found_key.offset - start; + goto not_found_em; + } + + if (found_type == BTRFS_FILE_EXTENT_REG) { + em->start = extent_start; + em->len = extent_end - extent_start; bytenr = btrfs_file_extent_disk_bytenr(leaf, item); if (bytenr == 0) { - em->start = extent_start; - em->len = extent_end - extent_start; em->block_start = EXTENT_MAP_HOLE; goto insert; } - em->start = extent_start; - em->len = extent_end - extent_start; if (compressed) { set_bit(EXTENT_FLAG_COMPRESSED, &em->flags); em->block_start = bytenr; @@ -3489,38 +3516,21 @@ again: } goto insert; } else if (found_type == BTRFS_FILE_EXTENT_INLINE) { - u64 page_start; unsigned long ptr; char *map; size_t size; size_t extent_offset; size_t copy_size; - size = btrfs_file_extent_inline_len(leaf, item); - extent_end = (extent_start + size + root->sectorsize - 1) & - ~((u64)root->sectorsize - 1); - if (start < extent_start || start >= extent_end) { - em->start = start; - if (start < extent_start) { - if (start + len <= extent_start) - goto not_found; - em->len = extent_end - extent_start; - } else { - em->len = len; - } - goto not_found_em; - } em->block_start = EXTENT_MAP_INLINE; - if (!page || create) { em->start = extent_start; - em->len = (size + root->sectorsize - 1) & - ~((u64)root->sectorsize - 1); + em->len = extent_end - extent_start; goto out; } - page_start = page_offset(page) + pg_offset; - extent_offset = page_start - extent_start; + size = btrfs_file_extent_inline_len(leaf, item); + extent_offset = page_offset(page) + pg_offset - extent_start; copy_size = min_t(u64, PAGE_CACHE_SIZE - pg_offset, size - extent_offset); em->start = extent_start + extent_offset; @@ -3570,6 +3580,7 @@ not_found: em->len = len; not_found_em: em->block_start = EXTENT_MAP_HOLE; + set_bit(EXTENT_FLAG_VACANCY, &em->flags); insert: btrfs_release_path(root, path); if (em->start > start || extent_map_end(em) <= start) { -- cgit v1.2.2