[PATCH v15 15/25] xfs: don't report dio_mem_align and dio_offset_align for fsverity files

Sashiko.dev reported that while fsverity files falls back to the
buffered IO for Direct I/O, they should not report non-zero values in
dio_mem_align and dio_offset_align, meaning it's not supported.

The STATX_DIOALIGN | STATX_DIO_READ_ALIGN flags are used to explicitly
report if DIO is supported or not. They can not indicate that fallback
to the buffered IO is used in this case. The zero alignment values also
mean that DIO is not supported on this file, see statx(2).

Signed-off-by: Andrey Albershteyn <[email protected]>
Acked-by: Eric Biggers <[email protected]>
---
 fs/xfs/xfs_iops.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/fs/xfs/xfs_iops.c b/fs/xfs/xfs_iops.c
index 55667cc762f8..70637cdcc299 100644
--- a/fs/xfs/xfs_iops.c
+++ b/fs/xfs/xfs_iops.c
@@ -35,6 +35,7 @@
 #include <linux/security.h>
 #include <linux/iversion.h>
 #include <linux/fiemap.h>
+#include <linux/fsverity.h>
 
 /*
  * Directories have different lock order w.r.t. mmap_lock compared to regular
@@ -580,6 +581,10 @@ xfs_report_dioalign(
 	struct block_device	*bdev = target->bt_bdev;
 
 	stat->result_mask |= STATX_DIOALIGN | STATX_DIO_READ_ALIGN;
+
+	if (fsverity_active(VFS_I(ip)))
+		return;
+
 	stat->dio_mem_align = bdev_dma_alignment(bdev) + 1;
 
 	/*
-- 
2.54.0