diff --git a/fs/ext4/extents.c b/fs/ext4/extents.c index bd42ab29efec..cd4479c08031 100644 --- a/fs/ext4/extents.c +++ b/fs/ext4/extents.c @@ -2202,14 +2202,39 @@ int ext4_ext_index_trans_blocks(struct inode *inode, int nrblocks, int chunk) } static int ext4_remove_blocks(handle_t *handle, struct inode *inode, - struct ext4_extent *ex, - ext4_lblk_t from, ext4_lblk_t to) + struct ext4_extent *ex, + ext4_fsblk_t *partial_cluster, + ext4_lblk_t from, ext4_lblk_t to) { + struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb); unsigned short ee_len = ext4_ext_get_actual_len(ex); + ext4_fsblk_t pblk; int flags = EXT4_FREE_BLOCKS_FORGET; if (S_ISDIR(inode->i_mode) || S_ISLNK(inode->i_mode)) flags |= EXT4_FREE_BLOCKS_METADATA; + /* + * For bigalloc file systems, we never free a partial cluster + * at the beginning of the extent. Instead, we make a note + * that we tried freeing the cluster, and check to see if we + * need to free it on a subsequent call to ext4_remove_blocks, + * or at the end of the ext4_truncate() operation. + */ + flags |= EXT4_FREE_BLOCKS_NOFREE_FIRST_CLUSTER; + + /* + * If we have a partial cluster, and it's different from the + * cluster of the last block, we need to explicitly free the + * partial cluster here. + */ + pblk = ext4_ext_pblock(ex) + ee_len - 1; + if (*partial_cluster && (EXT4_B2C(sbi, pblk) != *partial_cluster)) { + ext4_free_blocks(handle, inode, NULL, + EXT4_C2B(sbi, *partial_cluster), + sbi->s_cluster_ratio, flags); + *partial_cluster = 0; + } + #ifdef EXTENTS_STATS { struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb); @@ -2229,12 +2254,24 @@ static int ext4_remove_blocks(handle_t *handle, struct inode *inode, && to == le32_to_cpu(ex->ee_block) + ee_len - 1) { /* tail removal */ ext4_lblk_t num; - ext4_fsblk_t start; num = le32_to_cpu(ex->ee_block) + ee_len - from; - start = ext4_ext_pblock(ex) + ee_len - num; - ext_debug("free last %u blocks starting %llu\n", num, start); - ext4_free_blocks(handle, inode, NULL, start, num, flags); + pblk = ext4_ext_pblock(ex) + ee_len - num; + ext_debug("free last %u blocks starting %llu\n", num, pblk); + ext4_free_blocks(handle, inode, NULL, pblk, num, flags); + /* + * If the block range to be freed didn't start at the + * beginning of a cluster, and we removed the entire + * extent, save the partial cluster here, since we + * might need to delete if we determine that the + * truncate operation has removed all of the blocks in + * the cluster. + */ + if (pblk & (sbi->s_cluster_ratio - 1) && + (ee_len == num)) + *partial_cluster = EXT4_B2C(sbi, pblk); + else + *partial_cluster = 0; } else if (from == le32_to_cpu(ex->ee_block) && to <= le32_to_cpu(ex->ee_block) + ee_len - 1) { /* head removal */ @@ -2269,9 +2306,10 @@ static int ext4_remove_blocks(handle_t *handle, struct inode *inode, */ static int ext4_ext_rm_leaf(handle_t *handle, struct inode *inode, - struct ext4_ext_path *path, ext4_lblk_t start, - ext4_lblk_t end) + struct ext4_ext_path *path, ext4_fsblk_t *partial_cluster, + ext4_lblk_t start, ext4_lblk_t end) { + struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb); int err = 0, correct_index = 0; int depth = ext_depth(inode), credits; struct ext4_extent_header *eh; @@ -2423,7 +2461,8 @@ ext4_ext_rm_leaf(handle_t *handle, struct inode *inode, if (err) goto out; - err = ext4_remove_blocks(handle, inode, ex, a, b); + err = ext4_remove_blocks(handle, inode, ex, partial_cluster, + a, b); if (err) goto out; @@ -2471,7 +2510,8 @@ ext4_ext_rm_leaf(handle_t *handle, struct inode *inode, sizeof(struct ext4_extent)); } le16_add_cpu(&eh->eh_entries, -1); - } + } else + *partial_cluster = 0; ext_debug("new extent: %u:%u:%llu\n", block, num, ext4_ext_pblock(ex)); @@ -2483,6 +2523,25 @@ ext4_ext_rm_leaf(handle_t *handle, struct inode *inode, if (correct_index && eh->eh_entries) err = ext4_ext_correct_indexes(handle, inode, path); + /* + * If there is still a entry in the leaf node, check to see if + * it references the partial cluster. This is the only place + * where it could; if it doesn't, we can free the cluster. + */ + if (*partial_cluster && ex >= EXT_FIRST_EXTENT(eh) && + (EXT4_B2C(sbi, ext4_ext_pblock(ex) + ex_ee_len - 1) != + *partial_cluster)) { + int flags = EXT4_FREE_BLOCKS_FORGET; + + if (S_ISDIR(inode->i_mode) || S_ISLNK(inode->i_mode)) + flags |= EXT4_FREE_BLOCKS_METADATA; + + ext4_free_blocks(handle, inode, NULL, + EXT4_C2B(sbi, *partial_cluster), + sbi->s_cluster_ratio, flags); + *partial_cluster = 0; + } + /* if this leaf is free, then we should * remove it from index block above */ if (err == 0 && eh->eh_entries == 0 && path[depth].p_bh != NULL) @@ -2518,6 +2577,7 @@ static int ext4_ext_remove_space(struct inode *inode, ext4_lblk_t start) struct super_block *sb = inode->i_sb; int depth = ext_depth(inode); struct ext4_ext_path *path; + ext4_fsblk_t partial_cluster = 0; handle_t *handle; int i, err; @@ -2553,7 +2613,8 @@ again: if (i == depth) { /* this is leaf block */ err = ext4_ext_rm_leaf(handle, inode, path, - start, EXT_MAX_BLOCKS - 1); + &partial_cluster, start, + EXT_MAX_BLOCKS - 1); /* root level has p_bh == NULL, brelse() eats this */ brelse(path[i].p_bh); path[i].p_bh = NULL; @@ -3495,6 +3556,8 @@ int ext4_ext_map_blocks(handle_t *handle, struct inode *inode, ee_len = ext4_ext_get_actual_len(ex); /* if found extent covers block, simply return it */ if (in_range(map->m_lblk, ee_block, ee_len)) { + ext4_fsblk_t partial_cluster = 0; + newblock = map->m_lblk - ee_block + ee_start; /* number of remaining blocks in the extent */ allocated = ee_len - (map->m_lblk - ee_block); @@ -3578,7 +3641,8 @@ int ext4_ext_map_blocks(handle_t *handle, struct inode *inode, ext4_ext_invalidate_cache(inode); err = ext4_ext_rm_leaf(handle, inode, path, - map->m_lblk, map->m_lblk + punched_out); + &partial_cluster, map->m_lblk, + map->m_lblk + punched_out); if (!err && path->p_hdr->eh_entries == 0) { /*