diff options
Diffstat (limited to 'fs/ext4/extents.c')
-rw-r--r-- | fs/ext4/extents.c | 261 |
1 files changed, 261 insertions, 0 deletions
diff --git a/fs/ext4/extents.c b/fs/ext4/extents.c index a2bb87d75500..559100f3e23c 100644 --- a/fs/ext4/extents.c +++ b/fs/ext4/extents.c @@ -5804,3 +5804,264 @@ out: return err ? err : mapped; } + +/* + * Updates physical block address and unwritten status of extent + * starting at lblk start and of len. If such an extent doesn't exist, + * this function splits the extent tree appropriately to create an + * extent like this. This function is called in the fast commit + * replay path. Returns 0 on success and error on failure. + */ +int ext4_ext_replay_update_ex(struct inode *inode, ext4_lblk_t start, + int len, int unwritten, ext4_fsblk_t pblk) +{ + struct ext4_ext_path *path = NULL, *ppath; + struct ext4_extent *ex; + int ret; + + path = ext4_find_extent(inode, start, NULL, 0); + if (!path) + return -EINVAL; + ex = path[path->p_depth].p_ext; + if (!ex) { + ret = -EFSCORRUPTED; + goto out; + } + + if (le32_to_cpu(ex->ee_block) != start || + ext4_ext_get_actual_len(ex) != len) { + /* We need to split this extent to match our extent first */ + ppath = path; + down_write(&EXT4_I(inode)->i_data_sem); + ret = ext4_force_split_extent_at(NULL, inode, &ppath, start, 1); + up_write(&EXT4_I(inode)->i_data_sem); + if (ret) + goto out; + kfree(path); + path = ext4_find_extent(inode, start, NULL, 0); + if (IS_ERR(path)) + return -1; + ppath = path; + ex = path[path->p_depth].p_ext; + WARN_ON(le32_to_cpu(ex->ee_block) != start); + if (ext4_ext_get_actual_len(ex) != len) { + down_write(&EXT4_I(inode)->i_data_sem); + ret = ext4_force_split_extent_at(NULL, inode, &ppath, + start + len, 1); + up_write(&EXT4_I(inode)->i_data_sem); + if (ret) + goto out; + kfree(path); + path = ext4_find_extent(inode, start, NULL, 0); + if (IS_ERR(path)) + return -EINVAL; + ex = path[path->p_depth].p_ext; + } + } + if (unwritten) + ext4_ext_mark_unwritten(ex); + else + ext4_ext_mark_initialized(ex); + ext4_ext_store_pblock(ex, pblk); + down_write(&EXT4_I(inode)->i_data_sem); + ret = ext4_ext_dirty(NULL, inode, &path[path->p_depth]); + up_write(&EXT4_I(inode)->i_data_sem); +out: + ext4_ext_drop_refs(path); + kfree(path); + ext4_mark_inode_dirty(NULL, inode); + return ret; +} + +/* Try to shrink the extent tree */ +void ext4_ext_replay_shrink_inode(struct inode *inode, ext4_lblk_t end) +{ + struct ext4_ext_path *path = NULL; + struct ext4_extent *ex; + ext4_lblk_t old_cur, cur = 0; + + while (cur < end) { + path = ext4_find_extent(inode, cur, NULL, 0); + if (IS_ERR(path)) + return; + ex = path[path->p_depth].p_ext; + if (!ex) { + ext4_ext_drop_refs(path); + kfree(path); + ext4_mark_inode_dirty(NULL, inode); + return; + } + old_cur = cur; + cur = le32_to_cpu(ex->ee_block) + ext4_ext_get_actual_len(ex); + if (cur <= old_cur) + cur = old_cur + 1; + ext4_ext_try_to_merge(NULL, inode, path, ex); + down_write(&EXT4_I(inode)->i_data_sem); + ext4_ext_dirty(NULL, inode, &path[path->p_depth]); + up_write(&EXT4_I(inode)->i_data_sem); + ext4_mark_inode_dirty(NULL, inode); + ext4_ext_drop_refs(path); + kfree(path); + } +} + +/* Check if *cur is a hole and if it is, skip it */ +static void skip_hole(struct inode *inode, ext4_lblk_t *cur) +{ + int ret; + struct ext4_map_blocks map; + + map.m_lblk = *cur; + map.m_len = ((inode->i_size) >> inode->i_sb->s_blocksize_bits) - *cur; + + ret = ext4_map_blocks(NULL, inode, &map, 0); + if (ret != 0) + return; + *cur = *cur + map.m_len; +} + +/* Count number of blocks used by this inode and update i_blocks */ +int ext4_ext_replay_set_iblocks(struct inode *inode) +{ + struct ext4_ext_path *path = NULL, *path2 = NULL; + struct ext4_extent *ex; + ext4_lblk_t cur = 0, end; + int numblks = 0, i, ret = 0; + ext4_fsblk_t cmp1, cmp2; + struct ext4_map_blocks map; + + /* Determin the size of the file first */ + path = ext4_find_extent(inode, EXT_MAX_BLOCKS - 1, NULL, + EXT4_EX_NOCACHE); + if (IS_ERR(path)) + return PTR_ERR(path); + ex = path[path->p_depth].p_ext; + if (!ex) { + ext4_ext_drop_refs(path); + kfree(path); + goto out; + } + end = le32_to_cpu(ex->ee_block) + ext4_ext_get_actual_len(ex); + ext4_ext_drop_refs(path); + kfree(path); + + /* Count the number of data blocks */ + cur = 0; + while (cur < end) { + map.m_lblk = cur; + map.m_len = end - cur; + ret = ext4_map_blocks(NULL, inode, &map, 0); + if (ret < 0) + break; + if (ret > 0) + numblks += ret; + cur = cur + map.m_len; + } + + /* + * Count the number of extent tree blocks. We do it by looking up + * two successive extents and determining the difference between + * their paths. When path is different for 2 successive extents + * we compare the blocks in the path at each level and increment + * iblocks by total number of differences found. + */ + cur = 0; + skip_hole(inode, &cur); + path = ext4_find_extent(inode, cur, NULL, 0); + if (IS_ERR(path)) + goto out; + numblks += path->p_depth; + ext4_ext_drop_refs(path); + kfree(path); + while (cur < end) { + path = ext4_find_extent(inode, cur, NULL, 0); + if (IS_ERR(path)) + break; + ex = path[path->p_depth].p_ext; + if (!ex) { + ext4_ext_drop_refs(path); + kfree(path); + return 0; + } + cur = max(cur + 1, le32_to_cpu(ex->ee_block) + + ext4_ext_get_actual_len(ex)); + skip_hole(inode, &cur); + + path2 = ext4_find_extent(inode, cur, NULL, 0); + if (IS_ERR(path2)) { + ext4_ext_drop_refs(path); + kfree(path); + break; + } + ex = path2[path2->p_depth].p_ext; + for (i = 0; i <= max(path->p_depth, path2->p_depth); i++) { + cmp1 = cmp2 = 0; + if (i <= path->p_depth) + cmp1 = path[i].p_bh ? + path[i].p_bh->b_blocknr : 0; + if (i <= path2->p_depth) + cmp2 = path2[i].p_bh ? + path2[i].p_bh->b_blocknr : 0; + if (cmp1 != cmp2 && cmp2 != 0) + numblks++; + } + ext4_ext_drop_refs(path); + ext4_ext_drop_refs(path2); + kfree(path); + kfree(path2); + } + +out: + inode->i_blocks = numblks << (inode->i_sb->s_blocksize_bits - 9); + ext4_mark_inode_dirty(NULL, inode); + return 0; +} + +int ext4_ext_clear_bb(struct inode *inode) +{ + struct ext4_ext_path *path = NULL; + struct ext4_extent *ex; + ext4_lblk_t cur = 0, end; + int j, ret = 0; + struct ext4_map_blocks map; + + /* Determin the size of the file first */ + path = ext4_find_extent(inode, EXT_MAX_BLOCKS - 1, NULL, + EXT4_EX_NOCACHE); + if (IS_ERR(path)) + return PTR_ERR(path); + ex = path[path->p_depth].p_ext; + if (!ex) { + ext4_ext_drop_refs(path); + kfree(path); + return 0; + } + end = le32_to_cpu(ex->ee_block) + ext4_ext_get_actual_len(ex); + ext4_ext_drop_refs(path); + kfree(path); + + cur = 0; + while (cur < end) { + map.m_lblk = cur; + map.m_len = end - cur; + ret = ext4_map_blocks(NULL, inode, &map, 0); + if (ret < 0) + break; + if (ret > 0) { + path = ext4_find_extent(inode, map.m_lblk, NULL, 0); + if (!IS_ERR_OR_NULL(path)) { + for (j = 0; j < path->p_depth; j++) { + + ext4_mb_mark_bb(inode->i_sb, + path[j].p_block, 1, 0); + } + ext4_ext_drop_refs(path); + kfree(path); + } + ext4_mb_mark_bb(inode->i_sb, map.m_pblk, map.m_len, 0); + } + cur = cur + map.m_len; + } + + return 0; +} |