From: Jan Kara Subject: [PATCH 01/18] ext4: Handle transient ENOSPC properly for DAX Date: Mon, 18 Apr 2016 23:35:24 +0200 Message-ID: <1461015341-20153-2-git-send-email-jack@suse.cz> References: <1461015341-20153-1-git-send-email-jack@suse.cz> Cc: linux-ext4@vger.kernel.org, linux-mm@kvack.org, Ross Zwisler , Dan Williams , linux-nvdimm@lists.01.org, Matthew Wilcox , Jan Kara To: linux-fsdevel@vger.kernel.org Return-path: In-Reply-To: <1461015341-20153-1-git-send-email-jack@suse.cz> Sender: owner-linux-mm@kvack.org List-Id: linux-ext4.vger.kernel.org ext4_dax_get_blocks() was accidentally omitted fixing get blocks handlers to properly handle transient ENOSPC errors. Fix it now to use ext4_get_blocks_trans() helper which takes care of these errors. Signed-off-by: Jan Kara --- fs/ext4/inode.c | 75 +++++++++++++++------------------------------------------ 1 file changed, 20 insertions(+), 55 deletions(-) diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c index 981a1fc30eaa..3e0c06028668 100644 --- a/fs/ext4/inode.c +++ b/fs/ext4/inode.c @@ -3218,72 +3218,37 @@ static int ext4_releasepage(struct page *page, gfp_t wait) int ext4_dax_mmap_get_block(struct inode *inode, sector_t iblock, struct buffer_head *bh_result, int create) { - int ret, err; - int credits; - struct ext4_map_blocks map; - handle_t *handle = NULL; - int flags = 0; + int ret; ext4_debug("ext4_dax_mmap_get_block: inode %lu, create flag %d\n", inode->i_ino, create); - map.m_lblk = iblock; - map.m_len = bh_result->b_size >> inode->i_blkbits; - credits = ext4_chunk_trans_blocks(inode, map.m_len); - if (create) { - flags |= EXT4_GET_BLOCKS_PRE_IO | EXT4_GET_BLOCKS_CREATE_ZERO; - handle = ext4_journal_start(inode, EXT4_HT_MAP_BLOCKS, credits); - if (IS_ERR(handle)) { - ret = PTR_ERR(handle); - return ret; - } - } + if (!create) + return _ext4_get_block(inode, iblock, bh_result, 0); - ret = ext4_map_blocks(handle, inode, &map, flags); - if (create) { - err = ext4_journal_stop(handle); - if (ret >= 0 && err < 0) - ret = err; - } - if (ret <= 0) - goto out; - if (map.m_flags & EXT4_MAP_UNWRITTEN) { - int err2; + ret = ext4_get_block_trans(inode, iblock, bh_result, + EXT4_GET_BLOCKS_PRE_IO | + EXT4_GET_BLOCKS_CREATE_ZERO); + if (ret < 0) + return ret; + if (buffer_unwritten(bh_result)) { /* * We are protected by i_mmap_sem so we know block cannot go * away from under us even though we dropped i_data_sem. * Convert extent to written and write zeros there. - * - * Note: We may get here even when create == 0. */ - handle = ext4_journal_start(inode, EXT4_HT_MAP_BLOCKS, credits); - if (IS_ERR(handle)) { - ret = PTR_ERR(handle); - goto out; - } - - err = ext4_map_blocks(handle, inode, &map, - EXT4_GET_BLOCKS_CONVERT | EXT4_GET_BLOCKS_CREATE_ZERO); - if (err < 0) - ret = err; - err2 = ext4_journal_stop(handle); - if (err2 < 0 && ret > 0) - ret = err2; - } -out: - WARN_ON_ONCE(ret == 0 && create); - if (ret > 0) { - map_bh(bh_result, inode->i_sb, map.m_pblk); - /* - * At least for now we have to clear BH_New so that DAX code - * doesn't attempt to zero blocks again in a racy way. - */ - map.m_flags &= ~EXT4_MAP_NEW; - ext4_update_bh_state(bh_result, map.m_flags); - bh_result->b_size = map.m_len << inode->i_blkbits; - ret = 0; + ret = ext4_get_block_trans(inode, iblock, bh_result, + EXT4_GET_BLOCKS_CONVERT | + EXT4_GET_BLOCKS_CREATE_ZERO); + if (ret < 0) + return ret; } - return ret; + /* + * At least for now we have to clear BH_New so that DAX code + * doesn't attempt to zero blocks again in a racy way. + */ + clear_buffer_new(bh_result); + return 0; } #endif -- 2.6.6 -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org