diff options
| -rw-r--r-- | fs/btrfs/volumes.c | 29 |
1 files changed, 7 insertions, 22 deletions
diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c index 3471698fd831..04809d406813 100644 --- a/fs/btrfs/volumes.c +++ b/fs/btrfs/volumes.c @@ -7370,7 +7370,6 @@ static int read_one_dev(struct extent_buffer *leaf, int btrfs_read_sys_array(struct btrfs_fs_info *fs_info) { - struct btrfs_root *root = fs_info->tree_root; struct btrfs_super_block *super_copy = fs_info->super_copy; struct extent_buffer *sb; struct btrfs_disk_key *disk_key; @@ -7386,30 +7385,16 @@ int btrfs_read_sys_array(struct btrfs_fs_info *fs_info) struct btrfs_key key; ASSERT(BTRFS_SUPER_INFO_SIZE <= fs_info->nodesize); + /* - * This will create extent buffer of nodesize, superblock size is - * fixed to BTRFS_SUPER_INFO_SIZE. If nodesize > sb size, this will - * overallocate but we can keep it as-is, only the first page is used. + * We allocated a dummy extent, just to use extent buffer accessors. + * There will be unused space after BTRFS_SUPER_INFO_SIZE, but + * that's fine, we will not go beyond system chunk array anyway. */ - sb = btrfs_find_create_tree_block(fs_info, BTRFS_SUPER_INFO_OFFSET, - root->root_key.objectid, 0); - if (IS_ERR(sb)) - return PTR_ERR(sb); + sb = alloc_dummy_extent_buffer(fs_info, BTRFS_SUPER_INFO_OFFSET); + if (!sb) + return -ENOMEM; set_extent_buffer_uptodate(sb); - /* - * The sb extent buffer is artificial and just used to read the system array. - * set_extent_buffer_uptodate() call does not properly mark all it's - * pages up-to-date when the page is larger: extent does not cover the - * whole page and consequently check_page_uptodate does not find all - * the page's extents up-to-date (the hole beyond sb), - * write_extent_buffer then triggers a WARN_ON. - * - * Regular short extents go through mark_extent_buffer_dirty/writeback cycle, - * but sb spans only this function. Add an explicit SetPageUptodate call - * to silence the warning eg. on PowerPC 64. - */ - if (PAGE_SIZE > BTRFS_SUPER_INFO_SIZE) - SetPageUptodate(sb->pages[0]); write_extent_buffer(sb, super_copy, 0, BTRFS_SUPER_INFO_SIZE); array_size = btrfs_super_sys_array_size(super_copy); |