Xuan Zhuo
2022-Mar-08 12:34 UTC
[PATCH v7 04/26] virtio_ring: split: extract the logic of creating vring
Separate the logic of split to create vring queue.
For the convenience of passing parameters, add a structure
vring_split.
This feature is required for subsequent virtuqueue reset vring.
Signed-off-by: Xuan Zhuo <xuanzhuo at linux.alibaba.com>
---
drivers/virtio/virtio_ring.c | 74 +++++++++++++++++++++++++-----------
1 file changed, 51 insertions(+), 23 deletions(-)
diff --git a/drivers/virtio/virtio_ring.c b/drivers/virtio/virtio_ring.c
index b87130c8f312..d32793615451 100644
--- a/drivers/virtio/virtio_ring.c
+++ b/drivers/virtio/virtio_ring.c
@@ -85,6 +85,13 @@ struct vring_desc_extra {
u16 next; /* The next desc state in a list. */
};
+struct vring_split {
+ void *queue;
+ dma_addr_t dma_addr;
+ size_t queue_size_in_bytes;
+ struct vring vring;
+};
+
struct vring_virtqueue {
struct virtqueue vq;
@@ -915,28 +922,21 @@ static void *virtqueue_detach_unused_buf_split(struct
virtqueue *_vq)
return NULL;
}
-static struct virtqueue *vring_create_virtqueue_split(
- unsigned int index,
- unsigned int num,
- unsigned int vring_align,
- struct virtio_device *vdev,
- bool weak_barriers,
- bool may_reduce_num,
- bool context,
- bool (*notify)(struct virtqueue *),
- void (*callback)(struct virtqueue *),
- const char *name)
+static int vring_create_vring_split(struct vring_split *vring,
+ struct virtio_device *vdev,
+ unsigned int vring_align,
+ bool weak_barriers,
+ bool may_reduce_num,
+ u32 num)
{
- struct virtqueue *vq;
void *queue = NULL;
dma_addr_t dma_addr;
size_t queue_size_in_bytes;
- struct vring vring;
/* We assume num is a power of 2. */
if (num & (num - 1)) {
dev_warn(&vdev->dev, "Bad virtqueue length %u\n", num);
- return NULL;
+ return -EINVAL;
}
/* TODO: allocate each queue chunk individually */
@@ -947,11 +947,11 @@ static struct virtqueue *vring_create_virtqueue_split(
if (queue)
break;
if (!may_reduce_num)
- return NULL;
+ return -ENOMEM;
}
if (!num)
- return NULL;
+ return -ENOMEM;
if (!queue) {
/* Try to get a single page. You are my only hope! */
@@ -959,21 +959,49 @@ static struct virtqueue *vring_create_virtqueue_split(
&dma_addr, GFP_KERNEL|__GFP_ZERO);
}
if (!queue)
- return NULL;
+ return -ENOMEM;
queue_size_in_bytes = vring_size(num, vring_align);
- vring_init(&vring, num, queue, vring_align);
+ vring_init(&vring->vring, num, queue, vring_align);
+
+ vring->dma_addr = dma_addr;
+ vring->queue = queue;
+ vring->queue_size_in_bytes = queue_size_in_bytes;
+
+ return 0;
+}
+
+static struct virtqueue *vring_create_virtqueue_split(
+ unsigned int index,
+ unsigned int num,
+ unsigned int vring_align,
+ struct virtio_device *vdev,
+ bool weak_barriers,
+ bool may_reduce_num,
+ bool context,
+ bool (*notify)(struct virtqueue *),
+ void (*callback)(struct virtqueue *),
+ const char *name)
+{
+ struct vring_split vring;
+ struct virtqueue *vq;
+ int err;
+
+ err = vring_create_vring_split(&vring, vdev, vring_align, weak_barriers,
+ may_reduce_num, num);
+ if (err)
+ return NULL;
- vq = __vring_new_virtqueue(index, vring, vdev, weak_barriers, context,
+ vq = __vring_new_virtqueue(index, vring.vring, vdev, weak_barriers, context,
notify, callback, name);
if (!vq) {
- vring_free_queue(vdev, queue_size_in_bytes, queue,
- dma_addr);
+ vring_free_queue(vdev, vring.queue_size_in_bytes, vring.queue,
+ vring.dma_addr);
return NULL;
}
- to_vvq(vq)->split.queue_dma_addr = dma_addr;
- to_vvq(vq)->split.queue_size_in_bytes = queue_size_in_bytes;
+ to_vvq(vq)->split.queue_dma_addr = vring.dma_addr;
+ to_vvq(vq)->split.queue_size_in_bytes = vring.queue_size_in_bytes;
to_vvq(vq)->we_own_ring = true;
return vq;
--
2.31.0
Jason Wang
2022-Mar-09 06:46 UTC
[PATCH v7 04/26] virtio_ring: split: extract the logic of creating vring
? 2022/3/8 ??8:34, Xuan Zhuo ??:> Separate the logic of split to create vring queue. > > For the convenience of passing parameters, add a structure > vring_split. > > This feature is required for subsequent virtuqueue reset vring. > > Signed-off-by: Xuan Zhuo <xuanzhuo at linux.alibaba.com> > --- > drivers/virtio/virtio_ring.c | 74 +++++++++++++++++++++++++----------- > 1 file changed, 51 insertions(+), 23 deletions(-) > > diff --git a/drivers/virtio/virtio_ring.c b/drivers/virtio/virtio_ring.c > index b87130c8f312..d32793615451 100644 > --- a/drivers/virtio/virtio_ring.c > +++ b/drivers/virtio/virtio_ring.c > @@ -85,6 +85,13 @@ struct vring_desc_extra { > u16 next; /* The next desc state in a list. */ > }; > > +struct vring_split { > + void *queue; > + dma_addr_t dma_addr; > + size_t queue_size_in_bytes; > + struct vring vring; > +};So this structure will be only used in vring_create_vring_split() which seems not that useful. More see below.> + > struct vring_virtqueue { > struct virtqueue vq; > > @@ -915,28 +922,21 @@ static void *virtqueue_detach_unused_buf_split(struct virtqueue *_vq) > return NULL; > } > > -static struct virtqueue *vring_create_virtqueue_split( > - unsigned int index, > - unsigned int num, > - unsigned int vring_align, > - struct virtio_device *vdev, > - bool weak_barriers, > - bool may_reduce_num, > - bool context, > - bool (*notify)(struct virtqueue *), > - void (*callback)(struct virtqueue *), > - const char *name) > +static int vring_create_vring_split(struct vring_split *vring, > + struct virtio_device *vdev, > + unsigned int vring_align, > + bool weak_barriers, > + bool may_reduce_num, > + u32 num)I'd rename this as vring_alloc_queue_split() and let it simply return the address of queue like vring_alloc_queue(). And let it simple accept dma_addr_t *dma_adder instead of vring_split.> { > - struct virtqueue *vq; > void *queue = NULL; > dma_addr_t dma_addr; > size_t queue_size_in_bytes; > - struct vring vring; > > /* We assume num is a power of 2. */ > if (num & (num - 1)) { > dev_warn(&vdev->dev, "Bad virtqueue length %u\n", num); > - return NULL; > + return -EINVAL; > } > > /* TODO: allocate each queue chunk individually */ > @@ -947,11 +947,11 @@ static struct virtqueue *vring_create_virtqueue_split( > if (queue) > break; > if (!may_reduce_num) > - return NULL; > + return -ENOMEM; > } > > if (!num) > - return NULL; > + return -ENOMEM; > > if (!queue) { > /* Try to get a single page. You are my only hope! */ > @@ -959,21 +959,49 @@ static struct virtqueue *vring_create_virtqueue_split( > &dma_addr, GFP_KERNEL|__GFP_ZERO); > } > if (!queue) > - return NULL; > + return -ENOMEM; > > queue_size_in_bytes = vring_size(num, vring_align); > - vring_init(&vring, num, queue, vring_align); > + vring_init(&vring->vring, num, queue, vring_align);It's better to move this to its caller (vring_create_virtqueue_split), so we have rather simple logic below:> + > + vring->dma_addr = dma_addr; > + vring->queue = queue; > + vring->queue_size_in_bytes = queue_size_in_bytes; > + > + return 0; > +} > + > +static struct virtqueue *vring_create_virtqueue_split( > + unsigned int index, > + unsigned int num, > + unsigned int vring_align, > + struct virtio_device *vdev, > + bool weak_barriers, > + bool may_reduce_num, > + bool context, > + bool (*notify)(struct virtqueue *), > + void (*callback)(struct virtqueue *), > + const char *name) > +{ > + struct vring_split vring; > + struct virtqueue *vq; > + int err; > + > + err = vring_create_vring_split(&vring, vdev, vring_align, weak_barriers, > + may_reduce_num, num); > + if (err) > + return NULL;queue = vring_alloc_queue_split(vdev, &dma_addr, ...); if (!queue) ??? return -ENOMEM; vring_init(); ... Thanks> > - vq = __vring_new_virtqueue(index, vring, vdev, weak_barriers, context, > + vq = __vring_new_virtqueue(index, vring.vring, vdev, weak_barriers, context, > notify, callback, name); > if (!vq) { > - vring_free_queue(vdev, queue_size_in_bytes, queue, > - dma_addr); > + vring_free_queue(vdev, vring.queue_size_in_bytes, vring.queue, > + vring.dma_addr); > return NULL; > } > > - to_vvq(vq)->split.queue_dma_addr = dma_addr; > - to_vvq(vq)->split.queue_size_in_bytes = queue_size_in_bytes; > + to_vvq(vq)->split.queue_dma_addr = vring.dma_addr; > + to_vvq(vq)->split.queue_size_in_bytes = vring.queue_size_in_bytes; > to_vvq(vq)->we_own_ring = true; > > return vq;