3.16.7-ckt11 -stable review patch. If anyone has any objections, please let me know.
------------------ From: Theodore Ts'o <[email protected]> commit 713e8dde3e71e92db2d8cc8459d236ce1fb576ce upstream. We accidently aliased EXT4_EX_NOCACHE and EXT4_GET_CONVERT_UNWRITTEN falgs, which apparently was hiding a bug that was unmasked when this flag aliasing issue was addressed (see the subsequent commit). The reproduction case was: fsx -N 10000 -l 500000 -r 4096 -t 4096 -w 4096 -Z -R -W /vdb/junk ... which would cause fsx to report corruption in the data file. The fix we have is a bit of an overkill, but I'd much rather be conservative for now, and we can optimize ZERO_RANGE_FL handling later. The fact that we need to zap the extent_status cache for the inode is unfortunate, but correctness is far more important than performance. Signed-off-by: Theodore Ts'o <[email protected]> Cc: Namjae Jeon <[email protected]> Cc: Moritz Muehlenhoff <[email protected]> Signed-off-by: Luis Henriques <[email protected]> --- fs/ext4/extents.c | 21 ++++++++++++++------- 1 file changed, 14 insertions(+), 7 deletions(-) diff --git a/fs/ext4/extents.c b/fs/ext4/extents.c index 467661264ad0..2a4b4f3b1ae2 100644 --- a/fs/ext4/extents.c +++ b/fs/ext4/extents.c @@ -4796,7 +4796,8 @@ static long ext4_zero_range(struct file *file, loff_t offset, max_blocks -= lblk; flags = EXT4_GET_BLOCKS_CREATE_UNWRIT_EXT | - EXT4_GET_BLOCKS_CONVERT_UNWRITTEN; + EXT4_GET_BLOCKS_CONVERT_UNWRITTEN | + EXT4_EX_NOCACHE; if (mode & FALLOC_FL_KEEP_SIZE) flags |= EXT4_GET_BLOCKS_KEEP_SIZE; @@ -4834,15 +4835,21 @@ static long ext4_zero_range(struct file *file, loff_t offset, ext4_inode_block_unlocked_dio(inode); inode_dio_wait(inode); + ret = ext4_alloc_file_blocks(file, lblk, max_blocks, new_size, + flags, mode); + if (ret) + goto out_dio; /* * Remove entire range from the extent status tree. + * + * ext4_es_remove_extent(inode, lblk, max_blocks) is + * NOT sufficient. I'm not sure why this is the case, + * but let's be conservative and remove the extent + * status tree for the entire inode. There should be + * no outstanding delalloc extents thanks to the + * filemap_write_and_wait_range() call above. */ - ret = ext4_es_remove_extent(inode, lblk, max_blocks); - if (ret) - goto out_dio; - - ret = ext4_alloc_file_blocks(file, lblk, max_blocks, new_size, - flags, mode); + ret = ext4_es_remove_extent(inode, 0, EXT_MAX_BLOCKS); if (ret) goto out_dio; } -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
