xfs: don't forbid setting dax flag on directories if device doesn't dax (aaacdd25) · Commits · 戴 / test

On a directory, the DAX flag is merely a hint that files created in the directory should have the DAX flag set at creation time. We don't care if the underlying device supports DAX or not because directory metadata are always cached in DRAM. We don't care if new files get the flag even if the device doesn't support DAX because we always check for DAX support before setting the VFS flag (S_DAX). Signed-off-by:

Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by:

Dave Chinner <dchinner@redhat.com>

fs/xfs/xfs_ioctl.c

+7 −2

Original line number	Diff line number	Diff line
		@@ -1098,12 +1098,14 @@ xfs_ioctl_setattr_dax_invalidate(
		/*
		* 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 inherit hint.
		* 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) {
		if (!(S_ISREG(inode->i_mode) \|\| S_ISDIR(inode->i_mode)))
		return -EINVAL;
		if (!bdev_dax_supported(xfs_find_bdev_for_inode(VFS_I(ip)),
		if (S_ISREG(inode->i_mode) &&
		!bdev_dax_supported(xfs_find_bdev_for_inode(VFS_I(ip)),
		sb->s_blocksize))
		return -EINVAL;
		}
		@@ -1114,6 +1116,9 @@ xfs_ioctl_setattr_dax_invalidate(
		if (!(fa->fsx_xflags & FS_XFLAG_DAX) && !IS_DAX(inode))
		return 0;

		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);

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