virtio: Allocate virtqueue in page-size units
In preparation for explicit bouncing of virtqueue pages for devices
advertising the VIRTIO_F_IOMMU_PLATFORM feature, introduce a couple
of wrappers around virtqueue allocation and freeing operations,
ensuring that buffers are handled in terms of page-size units.
Signed-off-by: Will Deacon <willdeacon@google.com>
[ Paul: pick from the Android tree. Rebase to the upstream ]
Signed-off-by: Ying-Chun Liu (PaulLiu) <paul.liu@linaro.org>
Cc: Bin Meng <bmeng.cn@gmail.com>
Link: https://android.googlesource.com/platform/external/u-boot/+/b4bb5227d4cf4fdfcd8b4e1ff2692d3a54d1482a
Reviewed-by: Simon Glass <sjg@chromium.org>
diff --git a/drivers/virtio/virtio_ring.c b/drivers/virtio/virtio_ring.c
index f71bab7..5aeb13f 100644
--- a/drivers/virtio/virtio_ring.c
+++ b/drivers/virtio/virtio_ring.c
@@ -15,6 +15,17 @@
#include <virtio_ring.h>
#include <linux/bug.h>
#include <linux/compat.h>
+#include <linux/kernel.h>
+
+static void *virtio_alloc_pages(struct udevice *vdev, u32 npages)
+{
+ return memalign(PAGE_SIZE, npages * PAGE_SIZE);
+}
+
+static void virtio_free_pages(struct udevice *vdev, void *ptr, u32 npages)
+{
+ free(ptr);
+}
static unsigned int virtqueue_attach_desc(struct virtqueue *vq, unsigned int i,
struct virtio_sg *sg, u16 flags)
@@ -271,6 +282,8 @@
unsigned int vring_align,
struct udevice *udev)
{
+ struct virtio_dev_priv *uc_priv = dev_get_uclass_priv(udev);
+ struct udevice *vdev = uc_priv->vdev;
struct virtqueue *vq;
void *queue = NULL;
struct vring vring;
@@ -283,7 +296,9 @@
/* TODO: allocate each queue chunk individually */
for (; num && vring_size(num, vring_align) > PAGE_SIZE; num /= 2) {
- queue = memalign(PAGE_SIZE, vring_size(num, vring_align));
+ size_t sz = vring_size(num, vring_align);
+
+ queue = virtio_alloc_pages(vdev, DIV_ROUND_UP(sz, PAGE_SIZE));
if (queue)
break;
}
@@ -293,7 +308,7 @@
if (!queue) {
/* Try to get a single page. You are my only hope! */
- queue = memalign(PAGE_SIZE, vring_size(num, vring_align));
+ queue = virtio_alloc_pages(vdev, 1);
}
if (!queue)
return NULL;
@@ -303,7 +318,7 @@
vq = __vring_new_virtqueue(index, vring, udev);
if (!vq) {
- free(queue);
+ virtio_free_pages(vdev, queue, DIV_ROUND_UP(vring.size, PAGE_SIZE));
return NULL;
}
debug("(%s): created vring @ %p for vq @ %p with num %u\n", udev->name,
@@ -314,7 +329,8 @@
void vring_del_virtqueue(struct virtqueue *vq)
{
- free(vq->vring.desc);
+ virtio_free_pages(vq->vdev, vq->vring.desc,
+ DIV_ROUND_UP(vq->vring.size, PAGE_SIZE));
free(vq->vring_desc_shadow);
list_del(&vq->list);
free(vq);
diff --git a/include/virtio_ring.h b/include/virtio_ring.h
index c77c212..8f8a55c 100644
--- a/include/virtio_ring.h
+++ b/include/virtio_ring.h
@@ -86,6 +86,7 @@
struct vring {
unsigned int num;
+ size_t size;
struct vring_desc *desc;
struct vring_avail *avail;
struct vring_used *used;
@@ -137,16 +138,6 @@
#define vring_used_event(vr) ((vr)->avail->ring[(vr)->num])
#define vring_avail_event(vr) (*(__virtio16 *)&(vr)->used->ring[(vr)->num])
-static inline void vring_init(struct vring *vr, unsigned int num, void *p,
- unsigned long align)
-{
- vr->num = num;
- vr->desc = p;
- vr->avail = p + num * sizeof(struct vring_desc);
- vr->used = (void *)(((uintptr_t)&vr->avail->ring[num] +
- sizeof(__virtio16) + align - 1) & ~(align - 1));
-}
-
static inline unsigned int vring_size(unsigned int num, unsigned long align)
{
return ((sizeof(struct vring_desc) * num +
@@ -154,6 +145,17 @@
sizeof(__virtio16) * 3 + sizeof(struct vring_used_elem) * num;
}
+static inline void vring_init(struct vring *vr, unsigned int num, void *p,
+ unsigned long align)
+{
+ vr->num = num;
+ vr->size = vring_size(num, align);
+ vr->desc = p;
+ vr->avail = p + num * sizeof(struct vring_desc);
+ vr->used = (void *)(((uintptr_t)&vr->avail->ring[num] +
+ sizeof(__virtio16) + align - 1) & ~(align - 1));
+}
+
/*
* The following is used with USED_EVENT_IDX and AVAIL_EVENT_IDX.
* Assuming a given event_idx value from the other side, if we have just