Wang Shilong
2013-Mar-01 11:36 UTC
[PATCH 2/2] Btrfs: cleanup to make the function btrfs_delalloc_reserve_metadata more logic
From: Wang Shilong <wangsl-fnst@cn.fujitsu.com> The original code is a little confusing and not clear, The right way to deal with the kernel code like this: [...] if (ret) goto out; [...] So i move the common clean_up code to the place labeled with out_fail, this will be easier to maintain. Signed-off-by: Wang Shilong <wangsl-fnst@cn.fujitsu.com> --- fs/btrfs/extent-tree.c | 82 ++++++++++++++++++++++------------------------- 1 files changed, 38 insertions(+), 44 deletions(-) diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c index f0c960b..8e57870 100644 --- a/fs/btrfs/extent-tree.c +++ b/fs/btrfs/extent-tree.c @@ -4721,6 +4721,8 @@ int btrfs_delalloc_reserve_metadata(struct inode *inode, u64 num_bytes) enum btrfs_reserve_flush_enum flush = BTRFS_RESERVE_FLUSH_ALL; int ret = 0; bool delalloc_lock = true; + u64 to_free = 0; + unsigned dropped; /* If we are a free space inode we need to not flush since we will be in * the middle of a transaction commit. We also don''t need the delalloc @@ -4764,55 +4766,19 @@ int btrfs_delalloc_reserve_metadata(struct inode *inode, u64 num_bytes) csum_bytes = BTRFS_I(inode)->csum_bytes; spin_unlock(&BTRFS_I(inode)->lock); - if (root->fs_info->quota_enabled) + if (root->fs_info->quota_enabled) { ret = btrfs_qgroup_reserve(root, num_bytes + nr_extents * root->leafsize); + if (ret) + goto out_fail; + } - /* - * ret != 0 here means the qgroup reservation failed, we go straight to - * the shared error handling then. - */ - if (ret == 0) { - ret = reserve_metadata_bytes(root, block_rsv, - to_reserve, flush); - if (ret && root->fs_info->quota_enabled) { + ret = reserve_metadata_bytes(root, block_rsv, to_reserve, flush); + if (unlikely(ret)) { + if (root->fs_info->quota_enabled) btrfs_qgroup_free(root, num_bytes + nr_extents * root->leafsize); - } - } - - if (ret) { - u64 to_free = 0; - unsigned dropped; - - spin_lock(&BTRFS_I(inode)->lock); - dropped = drop_outstanding_extent(inode); - /* - * If the inodes csum_bytes is the same as the original - * csum_bytes then we know we haven''t raced with any free()ers - * so we can just reduce our inodes csum bytes and carry on. - * Otherwise we have to do the normal free thing to account for - * the case that the free side didn''t free up its reserve - * because of this outstanding reservation. - */ - if (BTRFS_I(inode)->csum_bytes == csum_bytes) - calc_csum_metadata_size(inode, num_bytes, 0); - else - to_free = calc_csum_metadata_size(inode, num_bytes, 0); - spin_unlock(&BTRFS_I(inode)->lock); - if (dropped) - to_free += btrfs_calc_trans_metadata_size(root, dropped); - - if (to_free) { - btrfs_block_rsv_release(root, block_rsv, to_free); - trace_btrfs_space_reservation(root->fs_info, - "delalloc", - btrfs_ino(inode), - to_free, 0); - } - if (delalloc_lock) - mutex_unlock(&BTRFS_I(inode)->delalloc_mutex); - return ret; + goto out_fail; } spin_lock(&BTRFS_I(inode)->lock); @@ -4833,6 +4799,34 @@ int btrfs_delalloc_reserve_metadata(struct inode *inode, u64 num_bytes) block_rsv_add_bytes(block_rsv, to_reserve, 1); return 0; + +out_fail: + spin_lock(&BTRFS_I(inode)->lock); + dropped = drop_outstanding_extent(inode); + /* + * If the inodes csum_bytes is the same as the original + * csum_bytes then we know we haven''t raced with any free()ers + * so we can just reduce our inodes csum bytes and carry on. + * Otherwise we have to do the normal free thing to account for + * the case that the free side didn''t free up its reserve + * because of this outstanding reservation. + */ + if (BTRFS_I(inode)->csum_bytes == csum_bytes) + calc_csum_metadata_size(inode, num_bytes, 0); + else + to_free = calc_csum_metadata_size(inode, num_bytes, 0); + spin_unlock(&BTRFS_I(inode)->lock); + if (dropped) + to_free += btrfs_calc_trans_metadata_size(root, dropped); + + if (to_free) { + btrfs_block_rsv_release(root, block_rsv, to_free); + trace_btrfs_space_reservation(root->fs_info, "delalloc", + btrfs_ino(inode), to_free, 0); + } + if (delalloc_lock) + mutex_unlock(&BTRFS_I(inode)->delalloc_mutex); + return ret; } /** -- 1.7.7.6 -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html