Re: [PATCH RFC v2 05/10] vringh: add vringh_kiov_length() helper

From: Jason Wang
Date: Mon Feb 01 2021 - 01:47:35 EST



On 2021/1/28 下午10:41, Stefano Garzarella wrote:
This new helper returns the total number of bytes covered by
a vringh_kiov.

Suggested-by: Jason Wang <jasowang@xxxxxxxxxx>
Signed-off-by: Stefano Garzarella <sgarzare@xxxxxxxxxx>


Acked-by: Jason Wang <jasowang@xxxxxxxxxx>


---
include/linux/vringh.h | 11 +++++++++++
1 file changed, 11 insertions(+)

diff --git a/include/linux/vringh.h b/include/linux/vringh.h
index 755211ebd195..84db7b8f912f 100644
--- a/include/linux/vringh.h
+++ b/include/linux/vringh.h
@@ -199,6 +199,17 @@ static inline void vringh_kiov_cleanup(struct vringh_kiov *kiov)
kiov->iov = NULL;
}
+static inline size_t vringh_kiov_length(struct vringh_kiov *kiov)
+{
+ size_t len = 0;
+ int i;
+
+ for (i = kiov->i; i < kiov->used; i++)
+ len += kiov->iov[i].iov_len;
+
+ return len;
+}
+
void vringh_kiov_advance(struct vringh_kiov *kiov, size_t len);
int vringh_getdesc_kern(struct vringh *vrh,