From ffb9e0f05fab5f7fe62c5d6964825e59e91be0db Mon Sep 17 00:00:00 2001 From: Qu Wenruo Date: Thu, 10 Oct 2019 10:39:27 +0800 Subject: btrfs: block-group: Refactor btrfs_read_block_groups() Refactor the work inside the loop of btrfs_read_block_groups() into one separate function, read_one_block_group(). This allows read_one_block_group to be reused for later BG_TREE feature. The refactor does the following extra fix: - Use btrfs_fs_incompat() to replace open-coded feature check Reviewed-by: Johannes Thumshirn Reviewed-by: Anand Jain Signed-off-by: Qu Wenruo Reviewed-by: David Sterba Signed-off-by: David Sterba --- fs/btrfs/block-group.c | 219 ++++++++++++++++++++++++------------------------- 1 file changed, 108 insertions(+), 111 deletions(-) (limited to 'fs/btrfs') diff --git a/fs/btrfs/block-group.c b/fs/btrfs/block-group.c index 9ce9c2e318cf..1bde24d336ca 100644 --- a/fs/btrfs/block-group.c +++ b/fs/btrfs/block-group.c @@ -1686,6 +1686,109 @@ static int check_chunk_block_group_mappings(struct btrfs_fs_info *fs_info) return ret; } +static int read_one_block_group(struct btrfs_fs_info *info, + struct btrfs_path *path, + int need_clear) +{ + struct extent_buffer *leaf = path->nodes[0]; + struct btrfs_block_group_cache *cache; + struct btrfs_space_info *space_info; + struct btrfs_key key; + struct btrfs_block_group_item bgi; + const bool mixed = btrfs_fs_incompat(info, MIXED_GROUPS); + int slot = path->slots[0]; + int ret; + + btrfs_item_key_to_cpu(leaf, &key, slot); + ASSERT(key.type == BTRFS_BLOCK_GROUP_ITEM_KEY); + + cache = btrfs_create_block_group_cache(info, key.objectid, key.offset); + if (!cache) + return -ENOMEM; + + if (need_clear) { + /* + * When we mount with old space cache, we need to + * set BTRFS_DC_CLEAR and set dirty flag. + * + * a) Setting 'BTRFS_DC_CLEAR' makes sure that we + * truncate the old free space cache inode and + * setup a new one. + * b) Setting 'dirty flag' makes sure that we flush + * the new space cache info onto disk. + */ + if (btrfs_test_opt(info, SPACE_CACHE)) + cache->disk_cache_state = BTRFS_DC_CLEAR; + } + read_extent_buffer(leaf, &bgi, btrfs_item_ptr_offset(leaf, slot), + sizeof(bgi)); + cache->used = btrfs_stack_block_group_used(&bgi); + cache->flags = btrfs_stack_block_group_flags(&bgi); + if (!mixed && ((cache->flags & BTRFS_BLOCK_GROUP_METADATA) && + (cache->flags & BTRFS_BLOCK_GROUP_DATA))) { + btrfs_err(info, +"bg %llu is a mixed block group but filesystem hasn't enabled mixed block groups", + cache->start); + ret = -EINVAL; + goto error; + } + + /* + * We need to exclude the super stripes now so that the space info has + * super bytes accounted for, otherwise we'll think we have more space + * than we actually do. + */ + ret = exclude_super_stripes(cache); + if (ret) { + /* We may have excluded something, so call this just in case. */ + btrfs_free_excluded_extents(cache); + goto error; + } + + /* + * Check for two cases, either we are full, and therefore don't need + * to bother with the caching work since we won't find any space, or we + * are empty, and we can just add all the space in and be done with it. + * This saves us _a_lot_ of time, particularly in the full case. + */ + if (key.offset == cache->used) { + cache->last_byte_to_unpin = (u64)-1; + cache->cached = BTRFS_CACHE_FINISHED; + btrfs_free_excluded_extents(cache); + } else if (cache->used == 0) { + cache->last_byte_to_unpin = (u64)-1; + cache->cached = BTRFS_CACHE_FINISHED; + add_new_free_space(cache, key.objectid, + key.objectid + key.offset); + btrfs_free_excluded_extents(cache); + } + + ret = btrfs_add_block_group_cache(info, cache); + if (ret) { + btrfs_remove_free_space_cache(cache); + goto error; + } + trace_btrfs_add_block_group(info, cache, 0); + btrfs_update_space_info(info, cache->flags, key.offset, + cache->used, cache->bytes_super, &space_info); + + cache->space_info = space_info; + + link_block_group(cache); + + set_avail_alloc_bits(info, cache->flags); + if (btrfs_chunk_readonly(info, cache->start)) { + inc_block_group_ro(cache, 1); + } else if (cache->used == 0) { + ASSERT(list_empty(&cache->bg_list)); + btrfs_mark_bg_unused(cache); + } + return 0; +error: + btrfs_put_block_group(cache); + return ret; +} + int btrfs_read_block_groups(struct btrfs_fs_info *info) { struct btrfs_path *path; @@ -1693,15 +1796,8 @@ int btrfs_read_block_groups(struct btrfs_fs_info *info) struct btrfs_block_group_cache *cache; struct btrfs_space_info *space_info; struct btrfs_key key; - struct btrfs_key found_key; - struct extent_buffer *leaf; int need_clear = 0; u64 cache_gen; - u64 feature; - int mixed; - - feature = btrfs_super_incompat_flags(info->super_copy); - mixed = !!(feature & BTRFS_FEATURE_INCOMPAT_MIXED_GROUPS); key.objectid = 0; key.offset = 0; @@ -1719,118 +1815,19 @@ int btrfs_read_block_groups(struct btrfs_fs_info *info) need_clear = 1; while (1) { - struct btrfs_block_group_item bgi; - ret = find_first_block_group(info, path, &key); if (ret > 0) break; if (ret != 0) goto error; - leaf = path->nodes[0]; - btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]); - - cache = btrfs_create_block_group_cache(info, found_key.objectid, - found_key.offset); - if (!cache) { - ret = -ENOMEM; - goto error; - } - - if (need_clear) { - /* - * When we mount with old space cache, we need to - * set BTRFS_DC_CLEAR and set dirty flag. - * - * a) Setting 'BTRFS_DC_CLEAR' makes sure that we - * truncate the old free space cache inode and - * setup a new one. - * b) Setting 'dirty flag' makes sure that we flush - * the new space cache info onto disk. - */ - if (btrfs_test_opt(info, SPACE_CACHE)) - cache->disk_cache_state = BTRFS_DC_CLEAR; - } - - read_extent_buffer(leaf, &bgi, - btrfs_item_ptr_offset(leaf, path->slots[0]), - sizeof(bgi)); - /* cache::chunk_objectid is unused */ - cache->used = btrfs_stack_block_group_used(&bgi); - cache->flags = btrfs_stack_block_group_flags(&bgi); - if (!mixed && - ((cache->flags & BTRFS_BLOCK_GROUP_METADATA) && - (cache->flags & BTRFS_BLOCK_GROUP_DATA))) { - btrfs_err(info, -"bg %llu is a mixed block group but filesystem hasn't enabled mixed block groups", - cache->start); - btrfs_put_block_group(cache); - ret = -EINVAL; + btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]); + ret = read_one_block_group(info, path, need_clear); + if (ret < 0) goto error; - } - - key.objectid = found_key.objectid + found_key.offset; + key.objectid += key.offset; + key.offset = 0; btrfs_release_path(path); - - /* - * We need to exclude the super stripes now so that the space - * info has super bytes accounted for, otherwise we'll think - * we have more space than we actually do. - */ - ret = exclude_super_stripes(cache); - if (ret) { - /* - * We may have excluded something, so call this just in - * case. - */ - btrfs_free_excluded_extents(cache); - btrfs_put_block_group(cache); - goto error; - } - - /* - * Check for two cases, either we are full, and therefore - * don't need to bother with the caching work since we won't - * find any space, or we are empty, and we can just add all - * the space in and be done with it. This saves us _a_lot_ of - * time, particularly in the full case. - */ - if (found_key.offset == cache->used) { - cache->last_byte_to_unpin = (u64)-1; - cache->cached = BTRFS_CACHE_FINISHED; - btrfs_free_excluded_extents(cache); - } else if (cache->used == 0) { - cache->last_byte_to_unpin = (u64)-1; - cache->cached = BTRFS_CACHE_FINISHED; - add_new_free_space(cache, found_key.objectid, - found_key.objectid + - found_key.offset); - btrfs_free_excluded_extents(cache); - } - - ret = btrfs_add_block_group_cache(info, cache); - if (ret) { - btrfs_remove_free_space_cache(cache); - btrfs_put_block_group(cache); - goto error; - } - - trace_btrfs_add_block_group(info, cache, 0); - btrfs_update_space_info(info, cache->flags, found_key.offset, - cache->used, - cache->bytes_super, &space_info); - - cache->space_info = space_info; - - link_block_group(cache); - - set_avail_alloc_bits(info, cache->flags); - if (btrfs_chunk_readonly(info, cache->start)) { - inc_block_group_ro(cache, 1); - } else if (cache->used == 0) { - ASSERT(list_empty(&cache->bg_list)); - btrfs_mark_bg_unused(cache); - } } list_for_each_entry_rcu(space_info, &info->space_info, list) { -- cgit v1.2.3-59-g8ed1b