Currently we don't allow unaligned writes without inode_lock. This is because zeroing of partial blocks could cause data corruption for racing unaligned writes to the same block. However DAX handles zeroing during block allocation and thus zeroing of partial blocks cannot race. Allow DAX unaligned IO to run without inode_lock.
Signed-off-by: Jan Kara <[email protected]> --- fs/ext4/file.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/fs/ext4/file.c b/fs/ext4/file.c index a6a7becb9465..55f8b922b76d 100644 --- a/fs/ext4/file.c +++ b/fs/ext4/file.c @@ -161,7 +161,8 @@ ext4_file_write_iter(struct kiocb *iocb, struct iov_iter *from) iocb->private = &overwrite; /* Check whether we do a DIO overwrite or not */ - if (o_direct && ext4_should_dioread_nolock(inode) && !unaligned_aio && + if (((o_direct && !unaligned_aio) || IS_DAX(inode)) && + ext4_should_dioread_nolock(inode) && ext4_overwrite_io(inode, iocb->ki_pos, iov_iter_count(from))) overwrite = 1; -- 2.6.6 _______________________________________________ Linux-nvdimm mailing list [email protected] https://lists.01.org/mailman/listinfo/linux-nvdimm
