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Message-Id: <1359617098-18451-1-git-send-email-dmonakhov@openvz.org> Date: Thu, 31 Jan 2013 11:24:58 +0400 From: Dmitry Monakhov <dmonakhov@...nvz.org> To: linux-ext4@...r.kernel.org Cc: tytso@....edu, jack@...e.cz, xiaoqiangnk@...il.com, Dmitry Monakhov <dmonakhov@...nvz.org> Subject: [PATCH] ext4: ext4_split_extent shoult take care about extent zeroout We have to update extent's state after first ext4_split_extent_at otherwise this result in following trace: ->ext4_ext_handle_uninitialized_extents (ex=[1000:20:uninit], lblock 1000, max_blocks 10) ->ext4_split_extent_at(ex=[1000,128], lblk 10010) /// First split ->ext4_ext_split() -> ENOSPC ->ext4_ext_zeroout ->ext4_ext_dirty -> ex=[1000:20:init] ->ext4_split_extent_at(ex=[1000,128], lblk 10000) /// Second split if(split == ee_block) if (split_flag & EXT4_EXT_MARK_UNINIT2) ext4_ext_mark_uninitialized(ex); ex=[1000:20:uninit] /// The bug! ->ext4_ext_dirty ->ex=[1000:20:uninit] At the end ext4_convert_unwritten_extents_endio() will findout large uninitialized extent. TESTCASE: https://github.com/dmonakhov/xfstests/commit/1a1c4f337d4d198803436c63a56625b1a78d8a5e Signed-off-by: Dmitry Monakhov <dmonakhov@...nvz.org> --- fs/ext4/extents.c | 14 ++++++++++---- 1 files changed, 10 insertions(+), 4 deletions(-) diff --git a/fs/ext4/extents.c b/fs/ext4/extents.c index 97cac01..7a3f679 100644 --- a/fs/ext4/extents.c +++ b/fs/ext4/extents.c @@ -3091,18 +3091,24 @@ static int ext4_split_extent(handle_t *handle, if (err) goto out; } - + /* Update path is required because previous ext4_split_extent_at() may + * result in split of original leaf or extent zeroout. + */ ext4_ext_drop_refs(path); path = ext4_ext_find_extent(inode, map->m_lblk, path); if (IS_ERR(path)) return PTR_ERR(path); + depth = ext_depth(inode); + ex = path[depth].p_ext; + uninitialized = ext4_ext_is_uninitialized(ex); if (map->m_lblk >= ee_block) { split_flag1 = split_flag & EXT4_EXT_MAY_ZEROOUT; - if (uninitialized) + if (uninitialized) { split_flag1 |= EXT4_EXT_MARK_UNINIT1; - if (split_flag & EXT4_EXT_MARK_UNINIT2) - split_flag1 |= EXT4_EXT_MARK_UNINIT2; + if (split_flag & EXT4_EXT_MARK_UNINIT2) + split_flag1 |= EXT4_EXT_MARK_UNINIT2; + } err = ext4_split_extent_at(handle, inode, path, map->m_lblk, split_flag1, flags); if (err) -- 1.7.1 -- To unsubscribe from this list: send the line "unsubscribe linux-ext4" in the body of a message to majordomo@...r.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
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