diff --git a/fs/ext4/extents.c b/fs/ext4/extents.c index 228eeaf2dccf31a5550f4008473951a6d660ec62..ee611daf07486547651290e53d478ab51cb9451e 100644 --- a/fs/ext4/extents.c +++ b/fs/ext4/extents.c @@ -2631,11 +2631,21 @@ static int ext4_ext_convert_to_initialized(handle_t *handle, struct ext4_extent *ex2 = NULL; struct ext4_extent *ex3 = NULL; struct ext4_extent_header *eh; - ext4_lblk_t ee_block; + ext4_lblk_t ee_block, eof_block; unsigned int allocated, ee_len, depth; ext4_fsblk_t newblock; int err = 0; int ret = 0; + int may_zeroout; + + ext_debug("ext4_ext_convert_to_initialized: inode %lu, logical" + "block %llu, max_blocks %u\n", inode->i_ino, + (unsigned long long)iblock, max_blocks); + + eof_block = (inode->i_size + inode->i_sb->s_blocksize - 1) >> + inode->i_sb->s_blocksize_bits; + if (eof_block < iblock + max_blocks) + eof_block = iblock + max_blocks; depth = ext_depth(inode); eh = path[depth].p_hdr; @@ -2644,16 +2654,23 @@ static int ext4_ext_convert_to_initialized(handle_t *handle, ee_len = ext4_ext_get_actual_len(ex); allocated = ee_len - (iblock - ee_block); newblock = iblock - ee_block + ext_pblock(ex); + ex2 = ex; orig_ex.ee_block = ex->ee_block; orig_ex.ee_len = cpu_to_le16(ee_len); ext4_ext_store_pblock(&orig_ex, ext_pblock(ex)); + /* + * It is safe to convert extent to initialized via explicit + * zeroout only if extent is fully insde i_size or new_size. + */ + may_zeroout = ee_block + ee_len <= eof_block; + err = ext4_ext_get_access(handle, inode, path + depth); if (err) goto out; /* If extent has less than 2*EXT4_EXT_ZERO_LEN zerout directly */ - if (ee_len <= 2*EXT4_EXT_ZERO_LEN) { + if (ee_len <= 2*EXT4_EXT_ZERO_LEN && may_zeroout) { err = ext4_ext_zeroout(inode, &orig_ex); if (err) goto fix_extent_len; @@ -2684,7 +2701,7 @@ static int ext4_ext_convert_to_initialized(handle_t *handle, if (allocated > max_blocks) { unsigned int newdepth; /* If extent has less than EXT4_EXT_ZERO_LEN zerout directly */ - if (allocated <= EXT4_EXT_ZERO_LEN) { + if (allocated <= EXT4_EXT_ZERO_LEN && may_zeroout) { /* * iblock == ee_block is handled by the zerouout * at the beginning. @@ -2760,7 +2777,7 @@ static int ext4_ext_convert_to_initialized(handle_t *handle, ex3->ee_len = cpu_to_le16(allocated - max_blocks); ext4_ext_mark_uninitialized(ex3); err = ext4_ext_insert_extent(handle, inode, path, ex3, 0); - if (err == -ENOSPC) { + if (err == -ENOSPC && may_zeroout) { err = ext4_ext_zeroout(inode, &orig_ex); if (err) goto fix_extent_len; @@ -2784,8 +2801,10 @@ static int ext4_ext_convert_to_initialized(handle_t *handle, * update the extent length after successful insert of the * split extent */ - orig_ex.ee_len = cpu_to_le16(ee_len - - ext4_ext_get_actual_len(ex3)); + ee_len -= ext4_ext_get_actual_len(ex3); + orig_ex.ee_len = cpu_to_le16(ee_len); + may_zeroout = ee_block + ee_len <= eof_block; + depth = newdepth; ext4_ext_drop_refs(path); path = ext4_ext_find_extent(inode, iblock, path); @@ -2809,7 +2828,7 @@ static int ext4_ext_convert_to_initialized(handle_t *handle, * otherwise give the extent a chance to merge to left */ if (le16_to_cpu(orig_ex.ee_len) <= EXT4_EXT_ZERO_LEN && - iblock != ee_block) { + iblock != ee_block && may_zeroout) { err = ext4_ext_zeroout(inode, &orig_ex); if (err) goto fix_extent_len; @@ -2878,7 +2897,7 @@ static int ext4_ext_convert_to_initialized(handle_t *handle, goto out; insert: err = ext4_ext_insert_extent(handle, inode, path, &newex, 0); - if (err == -ENOSPC) { + if (err == -ENOSPC && may_zeroout) { err = ext4_ext_zeroout(inode, &orig_ex); if (err) goto fix_extent_len; @@ -2938,14 +2957,21 @@ static int ext4_split_unwritten_extents(handle_t *handle, struct ext4_extent *ex2 = NULL; struct ext4_extent *ex3 = NULL; struct ext4_extent_header *eh; - ext4_lblk_t ee_block; + ext4_lblk_t ee_block, eof_block; unsigned int allocated, ee_len, depth; ext4_fsblk_t newblock; int err = 0; + int may_zeroout; + + ext_debug("ext4_split_unwritten_extents: inode %lu, logical" + "block %llu, max_blocks %u\n", inode->i_ino, + (unsigned long long)iblock, max_blocks); + + eof_block = (inode->i_size + inode->i_sb->s_blocksize - 1) >> + inode->i_sb->s_blocksize_bits; + if (eof_block < iblock + max_blocks) + eof_block = iblock + max_blocks; - ext_debug("ext4_split_unwritten_extents: inode %lu," - "iblock %llu, max_blocks %u\n", inode->i_ino, - (unsigned long long)iblock, max_blocks); depth = ext_depth(inode); eh = path[depth].p_hdr; ex = path[depth].p_ext; @@ -2953,11 +2979,18 @@ static int ext4_split_unwritten_extents(handle_t *handle, ee_len = ext4_ext_get_actual_len(ex); allocated = ee_len - (iblock - ee_block); newblock = iblock - ee_block + ext_pblock(ex); + ex2 = ex; orig_ex.ee_block = ex->ee_block; orig_ex.ee_len = cpu_to_le16(ee_len); ext4_ext_store_pblock(&orig_ex, ext_pblock(ex)); + /* + * It is safe to convert extent to initialized via explicit + * zeroout only if extent is fully insde i_size or new_size. + */ + may_zeroout = ee_block + ee_len <= eof_block; + /* * If the uninitialized extent begins at the same logical * block where the write begins, and the write completely @@ -2992,7 +3025,7 @@ static int ext4_split_unwritten_extents(handle_t *handle, ex3->ee_len = cpu_to_le16(allocated - max_blocks); ext4_ext_mark_uninitialized(ex3); err = ext4_ext_insert_extent(handle, inode, path, ex3, flags); - if (err == -ENOSPC) { + if (err == -ENOSPC && may_zeroout) { err = ext4_ext_zeroout(inode, &orig_ex); if (err) goto fix_extent_len; @@ -3016,8 +3049,10 @@ static int ext4_split_unwritten_extents(handle_t *handle, * update the extent length after successful insert of the * split extent */ - orig_ex.ee_len = cpu_to_le16(ee_len - - ext4_ext_get_actual_len(ex3)); + ee_len -= ext4_ext_get_actual_len(ex3); + orig_ex.ee_len = cpu_to_le16(ee_len); + may_zeroout = ee_block + ee_len <= eof_block; + depth = newdepth; ext4_ext_drop_refs(path); path = ext4_ext_find_extent(inode, iblock, path); @@ -3063,7 +3098,7 @@ static int ext4_split_unwritten_extents(handle_t *handle, goto out; insert: err = ext4_ext_insert_extent(handle, inode, path, &newex, flags); - if (err == -ENOSPC) { + if (err == -ENOSPC && may_zeroout) { err = ext4_ext_zeroout(inode, &orig_ex); if (err) goto fix_extent_len;