fs/xfs: Update xfs_ioctl_setattr_dax_invalidate()

Because of the separation of FS_XFLAG_DAX from S_DAX and the delayed
setting of S_DAX, data invalidation no longer needs to happen when
FS_XFLAG_DAX is changed.

Change xfs_ioctl_setattr_dax_invalidate() to be
xfs_ioctl_dax_check_set_cache() and alter the code to reflect the new
functionality.

Furthermore, we no longer need the locking so we remove the join_flags
logic.

Signed-off-by: Ira Weiny <ira.weiny@intel.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>

diff --git a/fs/xfs/xfs_ioctl.c b/fs/xfs/xfs_ioctl.c
index 104495ac187cfc69bd1a9fb6bb158ecd53117ad7..ff474f2c9acf6262dc8eaeb89477d7ecf4653dd2 100644 (file)
--- a/fs/xfs/xfs_ioctl.c
+++ b/fs/xfs/xfs_ioctl.c
@@ -1245,64 +1245,26 @@ xfs_ioctl_setattr_xflags(
        return 0;
 }
 
-/*
- * If we are changing DAX flags, we have to ensure the file is clean and any
- * cached objects in the address space are invalidated and removed. This
- * requires us to lock out other IO and page faults similar to a truncate
- * operation. The locks need to be held until the transaction has been committed
- * so that the cache invalidation is atomic with respect to the DAX flag
- * manipulation.
- */
-static int
-xfs_ioctl_setattr_dax_invalidate(
+static void
+xfs_ioctl_setattr_prepare_dax(
        struct xfs_inode        *ip,
-       struct fsxattr          *fa,
-       int                     *join_flags)
+       struct fsxattr          *fa)
 {
-       struct inode            *inode = VFS_I(ip);
-       struct super_block      *sb = inode->i_sb;
-       int                     error;
-
-       *join_flags = 0;
-
-       /*
-        * It is only valid to set the DAX flag on regular files and
-        * directories on filesystems where the block size is equal to the page
-        * size. On directories it serves as an inherited hint so we don't
-        * have to check the device for dax support or flush pagecache.
-        */
-       if (fa->fsx_xflags & FS_XFLAG_DAX) {
-               struct xfs_buftarg      *target = xfs_inode_buftarg(ip);
-
-               if (!bdev_dax_supported(target->bt_bdev, sb->s_blocksize))
-                       return -EINVAL;
-       }
-
-       /* If the DAX state is not changing, we have nothing to do here. */
-       if ((fa->fsx_xflags & FS_XFLAG_DAX) && IS_DAX(inode))
-               return 0;
-       if (!(fa->fsx_xflags & FS_XFLAG_DAX) && !IS_DAX(inode))
-               return 0;
+       struct xfs_mount        *mp = ip->i_mount;
+       struct inode            *inode = VFS_I(ip);
 
        if (S_ISDIR(inode->i_mode))
-               return 0;
-
-       /* lock, flush and invalidate mapping in preparation for flag change */
-       xfs_ilock(ip, XFS_MMAPLOCK_EXCL | XFS_IOLOCK_EXCL);
-       error = filemap_write_and_wait(inode->i_mapping);
-       if (error)
-               goto out_unlock;
-       error = invalidate_inode_pages2(inode->i_mapping);
-       if (error)
-               goto out_unlock;
-
-       *join_flags = XFS_MMAPLOCK_EXCL | XFS_IOLOCK_EXCL;
-       return 0;
+               return;
 
-out_unlock:
-       xfs_iunlock(ip, XFS_MMAPLOCK_EXCL | XFS_IOLOCK_EXCL);
-       return error;
+       if ((mp->m_flags & XFS_MOUNT_DAX_ALWAYS) ||
+           (mp->m_flags & XFS_MOUNT_DAX_NEVER))
+               return;
 
+       if (((fa->fsx_xflags & FS_XFLAG_DAX) &&
+           !(ip->i_d.di_flags2 & XFS_DIFLAG2_DAX)) ||
+           (!(fa->fsx_xflags & FS_XFLAG_DAX) &&
+            (ip->i_d.di_flags2 & XFS_DIFLAG2_DAX)))
+               d_mark_dontcache(inode);
 }
 
 /*
@@ -1310,17 +1272,10 @@ out_unlock:
  * have permission to do so. On success, return a clean transaction and the
  * inode locked exclusively ready for further operation specific checks. On
  * failure, return an error without modifying or locking the inode.
- *
- * The inode might already be IO locked on call. If this is the case, it is
- * indicated in @join_flags and we take full responsibility for ensuring they
- * are unlocked from now on. Hence if we have an error here, we still have to
- * unlock them. Otherwise, once they are joined to the transaction, they will
- * be unlocked on commit/cancel.
  */
 static struct xfs_trans *
 xfs_ioctl_setattr_get_trans(
-       struct xfs_inode        *ip,
-       int                     join_flags)
+       struct xfs_inode        *ip)
 {
        struct xfs_mount        *mp = ip->i_mount;
        struct xfs_trans        *tp;
@@ -1337,8 +1292,7 @@ xfs_ioctl_setattr_get_trans(
                goto out_unlock;
 
        xfs_ilock(ip, XFS_ILOCK_EXCL);
-       xfs_trans_ijoin(tp, ip, XFS_ILOCK_EXCL | join_flags);
-       join_flags = 0;
+       xfs_trans_ijoin(tp, ip, XFS_ILOCK_EXCL);
 
        /*
         * CAP_FOWNER overrides the following restrictions:
@@ -1359,8 +1313,6 @@ xfs_ioctl_setattr_get_trans(
 out_cancel:
        xfs_trans_cancel(tp);
 out_unlock:
-       if (join_flags)
-               xfs_iunlock(ip, join_flags);
        return ERR_PTR(error);
 }
 
@@ -1486,7 +1438,6 @@ xfs_ioctl_setattr(
        struct xfs_dquot        *pdqp = NULL;
        struct xfs_dquot        *olddquot = NULL;
        int                     code;
-       int                     join_flags = 0;
 
        trace_xfs_ioctl_setattr(ip);
 
@@ -1510,18 +1461,9 @@ xfs_ioctl_setattr(
                        return code;
        }
 
-       /*
-        * Changing DAX config may require inode locking for mapping
-        * invalidation. These need to be held all the way to transaction commit
-        * or cancel time, so need to be passed through to
-        * xfs_ioctl_setattr_get_trans() so it can apply them to the join call
-        * appropriately.
-        */
-       code = xfs_ioctl_setattr_dax_invalidate(ip, fa, &join_flags);
-       if (code)
-               goto error_free_dquots;
+       xfs_ioctl_setattr_prepare_dax(ip, fa);
 
-       tp = xfs_ioctl_setattr_get_trans(ip, join_flags);
+       tp = xfs_ioctl_setattr_get_trans(ip);
        if (IS_ERR(tp)) {
                code = PTR_ERR(tp);
                goto error_free_dquots;
@@ -1651,7 +1593,6 @@ xfs_ioc_setxflags(
        struct fsxattr          fa;
        struct fsxattr          old_fa;
        unsigned int            flags;
-       int                     join_flags = 0;
        int                     error;
 
        if (copy_from_user(&flags, arg, sizeof(flags)))
@@ -1668,18 +1609,9 @@ xfs_ioc_setxflags(
        if (error)
                return error;
 
-       /*
-        * Changing DAX config may require inode locking for mapping
-        * invalidation. These need to be held all the way to transaction commit
-        * or cancel time, so need to be passed through to
-        * xfs_ioctl_setattr_get_trans() so it can apply them to the join call
-        * appropriately.
-        */
-       error = xfs_ioctl_setattr_dax_invalidate(ip, &fa, &join_flags);
-       if (error)
-               goto out_drop_write;
+       xfs_ioctl_setattr_prepare_dax(ip, &fa);
 
-       tp = xfs_ioctl_setattr_get_trans(ip, join_flags);
+       tp = xfs_ioctl_setattr_get_trans(ip);
        if (IS_ERR(tp)) {
                error = PTR_ERR(tp);
                goto out_drop_write;