Module Name: src
Committed By: yamaguchi
Date: Wed Apr 19 00:38:30 UTC 2023
Modified Files:
src/sys/dev/pci: virtio.c
Log Message:
Fix not to allocate unnecessary descriptor
fixes PR/57358
To generate a diff of this commit:
cvs rdiff -u -r1.75 -r1.76 src/sys/dev/pci/virtio.c
Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.
Modified files:
Index: src/sys/dev/pci/virtio.c
diff -u src/sys/dev/pci/virtio.c:1.75 src/sys/dev/pci/virtio.c:1.76
--- src/sys/dev/pci/virtio.c:1.75 Wed Apr 19 00:23:45 2023
+++ src/sys/dev/pci/virtio.c Wed Apr 19 00:38:30 2023
@@ -1,4 +1,4 @@
-/* $NetBSD: virtio.c,v 1.75 2023/04/19 00:23:45 yamaguchi Exp $ */
+/* $NetBSD: virtio.c,v 1.76 2023/04/19 00:38:30 yamaguchi Exp $ */
/*
* Copyright (c) 2020 The NetBSD Foundation, Inc.
@@ -28,7 +28,7 @@
*/
#include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: virtio.c,v 1.75 2023/04/19 00:23:45 yamaguchi Exp $");
+__KERNEL_RCSID(0, "$NetBSD: virtio.c,v 1.76 2023/04/19 00:38:30 yamaguchi Exp $");
#include <sys/param.h>
#include <sys/systm.h>
@@ -1096,17 +1096,18 @@ virtio_enqueue_reserve(struct virtio_sof
}
vd[i].flags = virtio_rw16(sc, 0);
} else {
- uint16_t s;
+ if (nsegs > 1) {
+ uint16_t s;
- s = vq_alloc_slot(sc, vq, nsegs - 1);
- if (s == VRING_DESC_CHAIN_END) {
- vq_free_slot(sc, vq, slot);
- return EAGAIN;
+ s = vq_alloc_slot(sc, vq, nsegs - 1);
+ if (s == VRING_DESC_CHAIN_END) {
+ vq_free_slot(sc, vq, slot);
+ return EAGAIN;
+ }
+ vd->next = virtio_rw16(sc, s);
+ vd->flags = virtio_rw16(sc, VRING_DESC_F_NEXT);
}
- vd->next = virtio_rw16(sc, s);
- vd->flags = virtio_rw16(sc, VRING_DESC_F_NEXT);
-
vdx->desc_base = &vq->vq_desc[0];
vdx->desc_free_idx = slot;
}
