On 12/3/20 3:44 PM, Darrick J. Wong wrote:
> On Tue, Dec 01, 2020 at 01:16:09PM -0600, Eric Sandeen wrote:
>> We don't yet support dax on reflinked files, but that is in the works.
>>
>> Further, having the flag set does not automatically mean that the inode
>> is actually "in the CPU direct access state," which depends on several
>> other conditions in addition to the flag being set.
>>
>> As such, we should not catch this as corruption in the verifier - simply
>> not actually enabling S_DAX on reflinked files is enough for now.
>>
>> Fixes: 4f435ebe7d04 ("xfs: don't mix reflink and DAX mode for now")
>> Signed-off-by: Eric Sandeen <sandeen@xxxxxxxxxx>
>> ---
>> fs/xfs/libxfs/xfs_inode_buf.c | 4 ----
>> 1 file changed, 4 deletions(-)
>>
>> diff --git a/fs/xfs/libxfs/xfs_inode_buf.c b/fs/xfs/libxfs/xfs_inode_buf.c
>> index c667c63f2cb0..4d7410e49db4 100644
>> --- a/fs/xfs/libxfs/xfs_inode_buf.c
>> +++ b/fs/xfs/libxfs/xfs_inode_buf.c
>> @@ -547,10 +547,6 @@ xfs_dinode_verify(
>> if ((flags2 & XFS_DIFLAG2_REFLINK) && (flags & XFS_DIFLAG_REALTIME))
>> return __this_address;
>>
>> - /* don't let reflink and dax mix */
>> - if ((flags2 & XFS_DIFLAG2_REFLINK) && (flags2 & XFS_DIFLAG2_DAX))
>> - return __this_address;
>
> If we're going to let in inodes with the DAX and REFLINK iflags set,
> doesn't that mean that xfs_inode_should_enable_dax needs to return false
> if REFLINK is set?
I think it does already, no?
static bool
xfs_inode_should_enable_dax(
struct xfs_inode *ip)
{
if (!IS_ENABLED(CONFIG_FS_DAX))
return false;
if (ip->i_mount->m_flags & XFS_MOUNT_DAX_NEVER)
return false;
if (!xfs_inode_supports_dax(ip)) <------
return false;
----> xfs_inode_supports_dax --->
static bool
xfs_inode_supports_dax(
struct xfs_inode *ip)
{
struct xfs_mount *mp = ip->i_mount;
/* Only supported on regular files. */
if (!S_ISREG(VFS_I(ip)->i_mode))
return false;
/* Only supported on non-reflinked files. */
if (xfs_is_reflink_inode(ip))
return false;
