hulk inclusion category: feature bugzilla: https://gitee.com/openeuler/kernel/issues/I9DN5Z CVE: NA
--------------------------------
Factor out two new helpers from ext4_map_blocks(), no logic changes, ext4_map_query_blocks() query the file blocks mapping, and ext4_map_create_blocks() allocate new blocks and create a new extent.
Signed-off-by: Zhang Yi yi.zhang@huawei.com --- fs/ext4/inode.c | 219 ++++++++++++++++++++++++++---------------------- 1 file changed, 117 insertions(+), 102 deletions(-)
diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c index 68adfe6acfcd..8490daedea6a 100644 --- a/fs/ext4/inode.c +++ b/fs/ext4/inode.c @@ -453,6 +453,121 @@ static void ext4_map_blocks_es_recheck(handle_t *handle, } #endif /* ES_AGGRESSIVE_TEST */
+static int ext4_map_query_blocks(handle_t *handle, struct inode *inode, + struct ext4_map_blocks *map, int flags) +{ + unsigned int status; + int retval; + + if (ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS)) + retval = ext4_ext_map_blocks(handle, inode, map, 0); + else + retval = ext4_ind_map_blocks(handle, inode, map, 0); + + if (retval <= 0) + return retval; + + if (unlikely(retval != map->m_len)) { + ext4_warning(inode->i_sb, + "ES len assertion failed for inode " + "%lu: retval %d != map->m_len %d", + inode->i_ino, retval, map->m_len); + WARN_ON(1); + } + + status = map->m_flags & EXT4_MAP_UNWRITTEN ? + EXTENT_STATUS_UNWRITTEN : EXTENT_STATUS_WRITTEN; + if (!(flags & EXT4_GET_BLOCKS_DELALLOC_RESERVE) && + !(status & EXTENT_STATUS_WRITTEN) && + ext4_es_scan_range(inode, &ext4_es_is_delayed, map->m_lblk, + map->m_lblk + map->m_len - 1)) + status |= EXTENT_STATUS_DELAYED; + ext4_es_insert_extent(inode, map->m_lblk, map->m_len, + map->m_pblk, status); + + return retval; +} + +static int ext4_map_create_blocks(handle_t *handle, struct inode *inode, + struct ext4_map_blocks *map, int flags) +{ + struct extent_status es; + unsigned int status; + int err, retval = 0; + + /* + * Here we clear m_flags because after allocating an new extent, + * it will be set again. + */ + map->m_flags &= ~EXT4_MAP_FLAGS; + + /* + * We need to check for EXT4 here because migrate could have + * changed the inode type in between. + */ + if (ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS)) { + retval = ext4_ext_map_blocks(handle, inode, map, flags); + } else { + retval = ext4_ind_map_blocks(handle, inode, map, flags); + + /* + * We allocated new blocks which will result in i_data's + * format changing. Force the migrate to fail by clearing + * migrate flags. + */ + if (retval > 0 && map->m_flags & EXT4_MAP_NEW) + ext4_clear_inode_state(inode, EXT4_STATE_EXT_MIGRATE); + } + if (retval <= 0) + return retval; + + if (unlikely(retval != map->m_len)) { + ext4_warning(inode->i_sb, + "ES len assertion failed for inode %lu: " + "retval %d != map->m_len %d", + inode->i_ino, retval, map->m_len); + WARN_ON(1); + } + + /* + * We have to zeroout blocks before inserting them into extent + * status tree. Otherwise someone could look them up there and + * use them before they are really zeroed. We also have to + * unmap metadata before zeroing as otherwise writeback can + * overwrite zeros with stale data from block device. + */ + if (flags & EXT4_GET_BLOCKS_ZERO && + map->m_flags & EXT4_MAP_MAPPED && map->m_flags & EXT4_MAP_NEW) { + err = ext4_issue_zeroout(inode, map->m_lblk, map->m_pblk, + map->m_len); + if (err) + return err; + } + + /* + * If the extent has been zeroed out, we don't need to update + * extent status tree. + */ + if (flags & EXT4_GET_BLOCKS_PRE_IO && + ext4_es_lookup_extent(inode, map->m_lblk, NULL, &es)) { + if (ext4_es_is_written(&es)) + return retval; + } + + status = map->m_flags & EXT4_MAP_UNWRITTEN ? + EXTENT_STATUS_UNWRITTEN : EXTENT_STATUS_WRITTEN; + if (!(flags & EXT4_GET_BLOCKS_DELALLOC_RESERVE) && + !(status & EXTENT_STATUS_WRITTEN) && + ext4_es_scan_range(inode, &ext4_es_is_delayed, map->m_lblk, + map->m_lblk + map->m_len - 1)) + status |= EXTENT_STATUS_DELAYED; + + ext4_es_insert_extent(inode, map->m_lblk, map->m_len, + map->m_pblk, status); + + return retval; +} + /* * The ext4_map_blocks() function tries to look up the requested blocks, * and returns if the blocks are already mapped. @@ -546,32 +661,7 @@ int ext4_map_blocks(handle_t *handle, struct inode *inode, * file system block. */ down_read(&EXT4_I(inode)->i_data_sem); - if (ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS)) { - retval = ext4_ext_map_blocks(handle, inode, map, 0); - } else { - retval = ext4_ind_map_blocks(handle, inode, map, 0); - } - if (retval > 0) { - unsigned int status; - - if (unlikely(retval != map->m_len)) { - ext4_warning(inode->i_sb, - "ES len assertion failed for inode " - "%lu: retval %d != map->m_len %d", - inode->i_ino, retval, map->m_len); - WARN_ON(1); - } - - status = map->m_flags & EXT4_MAP_UNWRITTEN ? - EXTENT_STATUS_UNWRITTEN : EXTENT_STATUS_WRITTEN; - if (!(flags & EXT4_GET_BLOCKS_DELALLOC_RESERVE) && - !(status & EXTENT_STATUS_WRITTEN) && - ext4_es_scan_range(inode, &ext4_es_is_delayed, map->m_lblk, - map->m_lblk + map->m_len - 1)) - status |= EXTENT_STATUS_DELAYED; - ext4_es_insert_extent(inode, map->m_lblk, map->m_len, - map->m_pblk, status); - } + retval = ext4_map_query_blocks(handle, inode, map, flags); up_read((&EXT4_I(inode)->i_data_sem));
found: @@ -601,12 +691,6 @@ int ext4_map_blocks(handle_t *handle, struct inode *inode, if (!(flags & EXT4_GET_BLOCKS_CONVERT_UNWRITTEN)) return retval;
- /* - * Here we clear m_flags because after allocating an new extent, - * it will be set again. - */ - map->m_flags &= ~EXT4_MAP_FLAGS; - /* * New blocks allocate and/or writing to unwritten extent * will possibly result in updating i_data, so we take @@ -614,76 +698,7 @@ int ext4_map_blocks(handle_t *handle, struct inode *inode, * with create == 1 flag. */ down_write(&EXT4_I(inode)->i_data_sem); - - /* - * We need to check for EXT4 here because migrate - * could have changed the inode type in between - */ - if (ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS)) { - retval = ext4_ext_map_blocks(handle, inode, map, flags); - } else { - retval = ext4_ind_map_blocks(handle, inode, map, flags); - - if (retval > 0 && map->m_flags & EXT4_MAP_NEW) { - /* - * We allocated new blocks which will result in - * i_data's format changing. Force the migrate - * to fail by clearing migrate flags - */ - ext4_clear_inode_state(inode, EXT4_STATE_EXT_MIGRATE); - } - } - - if (retval > 0) { - unsigned int status; - - if (unlikely(retval != map->m_len)) { - ext4_warning(inode->i_sb, - "ES len assertion failed for inode " - "%lu: retval %d != map->m_len %d", - inode->i_ino, retval, map->m_len); - WARN_ON(1); - } - - /* - * We have to zeroout blocks before inserting them into extent - * status tree. Otherwise someone could look them up there and - * use them before they are really zeroed. We also have to - * unmap metadata before zeroing as otherwise writeback can - * overwrite zeros with stale data from block device. - */ - if (flags & EXT4_GET_BLOCKS_ZERO && - map->m_flags & EXT4_MAP_MAPPED && - map->m_flags & EXT4_MAP_NEW) { - ret = ext4_issue_zeroout(inode, map->m_lblk, - map->m_pblk, map->m_len); - if (ret) { - retval = ret; - goto out_sem; - } - } - - /* - * If the extent has been zeroed out, we don't need to update - * extent status tree. - */ - if ((flags & EXT4_GET_BLOCKS_PRE_IO) && - ext4_es_lookup_extent(inode, map->m_lblk, NULL, &es)) { - if (ext4_es_is_written(&es)) - goto out_sem; - } - status = map->m_flags & EXT4_MAP_UNWRITTEN ? - EXTENT_STATUS_UNWRITTEN : EXTENT_STATUS_WRITTEN; - if (!(flags & EXT4_GET_BLOCKS_DELALLOC_RESERVE) && - !(status & EXTENT_STATUS_WRITTEN) && - ext4_es_scan_range(inode, &ext4_es_is_delayed, map->m_lblk, - map->m_lblk + map->m_len - 1)) - status |= EXTENT_STATUS_DELAYED; - ext4_es_insert_extent(inode, map->m_lblk, map->m_len, - map->m_pblk, status); - } - -out_sem: + retval = ext4_map_create_blocks(handle, inode, map, flags); up_write((&EXT4_I(inode)->i_data_sem)); if (retval > 0 && map->m_flags & EXT4_MAP_MAPPED) { ret = check_block_validity(inode, map);