From: Akira Fujita Subject: Re: [PATCH 1/2]ext4: Fix exchanged block count in EXT4_IOC_MOVE_EXT failure Date: Fri, 09 Oct 2009 08:56:07 +0900 Message-ID: <4ACE7C17.106@rs.jp.nec.com> References: <4AC5B8C5.8000205@rs.jp.nec.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-2022-JP Content-Transfer-Encoding: 7bit To: Theodore Tso , linux-ext4@vger.kernel.org Return-path: Received: from TYO202.gate.nec.co.jp ([202.32.8.206]:45315 "EHLO tyo202.gate.nec.co.jp" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1760158AbZJHX5k (ORCPT ); Thu, 8 Oct 2009 19:57:40 -0400 In-Reply-To: <4AC5B8C5.8000205@rs.jp.nec.com> Sender: linux-ext4-owner@vger.kernel.org List-ID: Hi Ted, If my patches do not seem to have a problem, would you add them to the ext4 patch queue? http://marc.info/?l=linux-ext4&m=125447192609335&w=2 http://marc.info/?l=linux-ext4&m=125447192709338&w=2 Regards, Akira Fujita Akira Fujita wrote: > ext4: Fix block count in EXT4_IOC_MOVE_EXT failure > > From: Akira Fujita > > The halfway exchanged block count should be returned to the user-space, > if EXT4_IOC_MOVE_EXT is failed for some reasons > in the environment where block size is not same as page size. > But current EXT4_IOC_MOVE_EXT returns > page-aligned block count to the user-space. > The patch fixes this issue. > > Signed-off-by: Akira Fujita > --- > fs/ext4/move_extent.c | 139 ++++++++++++++++++++++++++----------------------- > 1 files changed, 73 insertions(+), 66 deletions(-) > > diff --git a/fs/ext4/move_extent.c b/fs/ext4/move_extent.c > index 25b6b14..83f8c9e 100644 > --- a/fs/ext4/move_extent.c > +++ b/fs/ext4/move_extent.c > @@ -661,6 +661,7 @@ mext_calc_swap_extents(struct ext4_extent *tmp_dext, > * @donor_inode: donor inode > * @from: block offset of orig_inode > * @count: block count to be replaced > + * @err: pointer to save return value > * > * Replace original inode extents and donor inode extents page by page. > * We implement this replacement in the following three steps: > @@ -671,19 +672,18 @@ mext_calc_swap_extents(struct ext4_extent *tmp_dext, > * 3. Change the block information of donor inode to point at the saved > * original inode blocks in the dummy extents. > * > - * Return 0 on success, or a negative error value on failure. > + * Return replaced block count. > */ > static int > mext_replace_branches(handle_t *handle, struct inode *orig_inode, > struct inode *donor_inode, ext4_lblk_t from, > - ext4_lblk_t count) > + ext4_lblk_t count, int *err) > { > struct ext4_ext_path *orig_path = NULL; > struct ext4_ext_path *donor_path = NULL; > struct ext4_extent *oext, *dext; > struct ext4_extent tmp_dext, tmp_oext; > ext4_lblk_t orig_off = from, donor_off = from; > - int err = 0; > int depth; > int replaced_count = 0; > int dext_alen; > @@ -691,13 +691,13 @@ mext_replace_branches(handle_t *handle, struct inode *orig_inode, > mext_double_down_write(orig_inode, donor_inode); > > /* Get the original extent for the block "orig_off" */ > - err = get_ext_path(orig_inode, orig_off, &orig_path); > - if (err) > + *err = get_ext_path(orig_inode, orig_off, &orig_path); > + if (*err) > goto out; > > /* Get the donor extent for the head */ > - err = get_ext_path(donor_inode, donor_off, &donor_path); > - if (err) > + *err = get_ext_path(donor_inode, donor_off, &donor_path); > + if (*err) > goto out; > depth = ext_depth(orig_inode); > oext = orig_path[depth].p_ext; > @@ -707,9 +707,9 @@ mext_replace_branches(handle_t *handle, struct inode *orig_inode, > dext = donor_path[depth].p_ext; > tmp_dext = *dext; > > - err = mext_calc_swap_extents(&tmp_dext, &tmp_oext, orig_off, > + *err = mext_calc_swap_extents(&tmp_dext, &tmp_oext, orig_off, > donor_off, count); > - if (err) > + if (*err) > goto out; > > /* Loop for the donor extents */ > @@ -718,7 +718,7 @@ mext_replace_branches(handle_t *handle, struct inode *orig_inode, > if (!dext) { > ext4_error(donor_inode->i_sb, __func__, > "The extent for donor must be found"); > - err = -EIO; > + *err = -EIO; > goto out; > } else if (donor_off != le32_to_cpu(tmp_dext.ee_block)) { > ext4_error(donor_inode->i_sb, __func__, > @@ -726,20 +726,20 @@ mext_replace_branches(handle_t *handle, struct inode *orig_inode, > "extent(%u) should be equal", > donor_off, > le32_to_cpu(tmp_dext.ee_block)); > - err = -EIO; > + *err = -EIO; > goto out; > } > > /* Set donor extent to orig extent */ > - err = mext_leaf_block(handle, orig_inode, > + *err = mext_leaf_block(handle, orig_inode, > orig_path, &tmp_dext, &orig_off); > - if (err < 0) > + if (*err) > goto out; > > /* Set orig extent to donor extent */ > - err = mext_leaf_block(handle, donor_inode, > + *err = mext_leaf_block(handle, donor_inode, > donor_path, &tmp_oext, &donor_off); > - if (err < 0) > + if (*err) > goto out; > > dext_alen = ext4_ext_get_actual_len(&tmp_dext); > @@ -753,35 +753,25 @@ mext_replace_branches(handle_t *handle, struct inode *orig_inode, > > if (orig_path) > ext4_ext_drop_refs(orig_path); > - err = get_ext_path(orig_inode, orig_off, &orig_path); > - if (err) > + *err = get_ext_path(orig_inode, orig_off, &orig_path); > + if (*err) > goto out; > depth = ext_depth(orig_inode); > oext = orig_path[depth].p_ext; > - if (le32_to_cpu(oext->ee_block) + > - ext4_ext_get_actual_len(oext) <= orig_off) { > - err = 0; > - goto out; > - } > tmp_oext = *oext; > > if (donor_path) > ext4_ext_drop_refs(donor_path); > - err = get_ext_path(donor_inode, donor_off, &donor_path); > - if (err) > + *err = get_ext_path(donor_inode, donor_off, &donor_path); > + if (*err) > goto out; > depth = ext_depth(donor_inode); > dext = donor_path[depth].p_ext; > - if (le32_to_cpu(dext->ee_block) + > - ext4_ext_get_actual_len(dext) <= donor_off) { > - err = 0; > - goto out; > - } > tmp_dext = *dext; > > - err = mext_calc_swap_extents(&tmp_dext, &tmp_oext, orig_off, > + *err = mext_calc_swap_extents(&tmp_dext, &tmp_oext, orig_off, > donor_off, count - replaced_count); > - if (err) > + if (*err) > goto out; > } > > @@ -796,7 +786,7 @@ out: > } > > mext_double_up_write(orig_inode, donor_inode); > - return err; > + return replaced_count; > } > > /** > @@ -808,16 +798,17 @@ out: > * @data_offset_in_page: block index where data swapping starts > * @block_len_in_page: the number of blocks to be swapped > * @uninit: orig extent is uninitialized or not > + * @err: pointer to save return value > * > * Save the data in original inode blocks and replace original inode extents > * with donor inode extents by calling mext_replace_branches(). > - * Finally, write out the saved data in new original inode blocks. Return 0 > - * on success, or a negative error value on failure. > + * Finally, write out the saved data in new original inode blocks. Return > + * replaced block count. > */ > static int > move_extent_per_page(struct file *o_filp, struct inode *donor_inode, > pgoff_t orig_page_offset, int data_offset_in_page, > - int block_len_in_page, int uninit) > + int block_len_in_page, int uninit, int *err) > { > struct inode *orig_inode = o_filp->f_dentry->d_inode; > struct address_space *mapping = orig_inode->i_mapping; > @@ -829,9 +820,11 @@ move_extent_per_page(struct file *o_filp, struct inode *donor_inode, > long long offs = orig_page_offset << PAGE_CACHE_SHIFT; > unsigned long blocksize = orig_inode->i_sb->s_blocksize; > unsigned int w_flags = 0; > - unsigned int tmp_data_len, data_len; > + unsigned int tmp_data_size, data_size, replaced_size; > void *fsdata; > - int ret, i, jblocks; > + int i, jblocks; > + int err2 = 0; > + int replaced_count = 0; > int blocks_per_page = PAGE_CACHE_SIZE >> orig_inode->i_blkbits; > > /* > @@ -841,8 +834,8 @@ move_extent_per_page(struct file *o_filp, struct inode *donor_inode, > jblocks = ext4_writepage_trans_blocks(orig_inode) * 2; > handle = ext4_journal_start(orig_inode, jblocks); > if (IS_ERR(handle)) { > - ret = PTR_ERR(handle); > - return ret; > + *err = PTR_ERR(handle); > + return 0; > } > > if (segment_eq(get_fs(), KERNEL_DS)) > @@ -858,9 +851,9 @@ move_extent_per_page(struct file *o_filp, struct inode *donor_inode, > * Just swap data blocks between orig and donor. > */ > if (uninit) { > - ret = mext_replace_branches(handle, orig_inode, > - donor_inode, orig_blk_offset, > - block_len_in_page); > + replaced_count = mext_replace_branches(handle, orig_inode, > + donor_inode, orig_blk_offset, > + block_len_in_page, err); > > /* Clear the inode cache not to refer to the old data */ > ext4_ext_invalidate_cache(orig_inode); > @@ -870,27 +863,28 @@ move_extent_per_page(struct file *o_filp, struct inode *donor_inode, > > offs = (long long)orig_blk_offset << orig_inode->i_blkbits; > > - /* Calculate data_len */ > + /* Calculate data_size */ > if ((orig_blk_offset + block_len_in_page - 1) == > ((orig_inode->i_size - 1) >> orig_inode->i_blkbits)) { > /* Replace the last block */ > - tmp_data_len = orig_inode->i_size & (blocksize - 1); > + tmp_data_size = orig_inode->i_size & (blocksize - 1); > /* > - * If data_len equal zero, it shows data_len is multiples of > + * If data_size equal zero, it shows data_size is multiples of > * blocksize. So we set appropriate value. > */ > - if (tmp_data_len == 0) > - tmp_data_len = blocksize; > + if (tmp_data_size == 0) > + tmp_data_size = blocksize; > > - data_len = tmp_data_len + > + data_size = tmp_data_size + > ((block_len_in_page - 1) << orig_inode->i_blkbits); > - } else { > - data_len = block_len_in_page << orig_inode->i_blkbits; > - } > + } else > + data_size = block_len_in_page << orig_inode->i_blkbits; > + > + replaced_size = data_size; > > - ret = a_ops->write_begin(o_filp, mapping, offs, data_len, w_flags, > + *err = a_ops->write_begin(o_filp, mapping, offs, data_size, w_flags, > &page, &fsdata); > - if (unlikely(ret < 0)) > + if (unlikely(*err < 0)) > goto out; > > if (!PageUptodate(page)) { > @@ -911,10 +905,17 @@ move_extent_per_page(struct file *o_filp, struct inode *donor_inode, > /* Release old bh and drop refs */ > try_to_release_page(page, 0); > > - ret = mext_replace_branches(handle, orig_inode, donor_inode, > - orig_blk_offset, block_len_in_page); > - if (ret < 0) > - goto out; > + replaced_count = mext_replace_branches(handle, orig_inode, donor_inode, > + orig_blk_offset, block_len_in_page, > + &err2); > + if (err2) { > + if (replaced_count) { > + block_len_in_page = replaced_count; > + replaced_size = > + block_len_in_page << orig_inode->i_blkbits; > + } else > + goto out; > + } > > /* Clear the inode cache not to refer to the old data */ > ext4_ext_invalidate_cache(orig_inode); > @@ -928,16 +929,16 @@ move_extent_per_page(struct file *o_filp, struct inode *donor_inode, > bh = bh->b_this_page; > > for (i = 0; i < block_len_in_page; i++) { > - ret = ext4_get_block(orig_inode, > + *err = ext4_get_block(orig_inode, > (sector_t)(orig_blk_offset + i), bh, 0); > - if (ret < 0) > + if (*err < 0) > goto out; > > if (bh->b_this_page != NULL) > bh = bh->b_this_page; > } > > - ret = a_ops->write_end(o_filp, mapping, offs, data_len, data_len, > + *err = a_ops->write_end(o_filp, mapping, offs, data_size, replaced_size, > page, fsdata); > page = NULL; > > @@ -951,7 +952,10 @@ out: > out2: > ext4_journal_stop(handle); > > - return ret < 0 ? ret : 0; > + if (err2) > + *err = err2; > + > + return replaced_count; > } > > /** > @@ -1367,15 +1371,17 @@ ext4_move_extents(struct file *o_filp, struct file *d_filp, > while (orig_page_offset <= seq_end_page) { > > /* Swap original branches with new branches */ > - ret1 = move_extent_per_page(o_filp, donor_inode, > + block_len_in_page = move_extent_per_page( > + o_filp, donor_inode, > orig_page_offset, > data_offset_in_page, > - block_len_in_page, uninit); > - if (ret1 < 0) > - goto out; > - orig_page_offset++; > + block_len_in_page, uninit, > + &ret1); > + > /* Count how many blocks we have exchanged */ > *moved_len += block_len_in_page; > + if (ret1 < 0) > + goto out; > if (*moved_len > len) { > ext4_error(orig_inode->i_sb, __func__, > "We replaced blocks too much! " > @@ -1385,6 +1391,7 @@ ext4_move_extents(struct file *o_filp, struct file *d_filp, > goto out; > } > > + orig_page_offset++; > data_offset_in_page = 0; > rest_blocks -= block_len_in_page; > if (rest_blocks > blocks_per_page) > -- > To unsubscribe from this list: send the line "unsubscribe linux-ext4" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html > -- Akira Fujita The First Fundamental Software Development Group, Software Development Division, NEC Software Tohoku, Ltd.