| Message ID | 20220720030436.79520-9-xuanzhuo@linux.alibaba.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | virtio pci support VIRTIO_F_RING_RESET | expand |
在 2022/7/20 11:04, Xuan Zhuo 写道: > Separate the logic of split to create vring queue. > > This feature is required for subsequent virtuqueue reset vring. > > Signed-off-by: Xuan Zhuo <xuanzhuo@linux.alibaba.com> > --- > drivers/virtio/virtio_ring.c | 68 ++++++++++++++++++++++-------------- > 1 file changed, 42 insertions(+), 26 deletions(-) > > diff --git a/drivers/virtio/virtio_ring.c b/drivers/virtio/virtio_ring.c > index c94c5461e702..c7971438bb2c 100644 > --- a/drivers/virtio/virtio_ring.c > +++ b/drivers/virtio/virtio_ring.c > @@ -950,28 +950,19 @@ static void vring_free_split(struct vring_virtqueue_split *vring_split, > kfree(vring_split->desc_extra); > } > > -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_alloc_queue_split(struct vring_virtqueue_split *vring_split, > + struct virtio_device *vdev, > + u32 num, > + unsigned int vring_align, > + bool may_reduce_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 */ > @@ -982,11 +973,11 @@ 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! */ > @@ -994,21 +985,46 @@ static struct virtqueue *vring_create_virtqueue_split( > &dma_addr, GFP_KERNEL|__GFP_ZERO); > } > if (!queue) > - return NULL; > + return -ENOMEM; > + > + vring_init(&vring_split->vring, num, queue, vring_align); > > - queue_size_in_bytes = vring_size(num, vring_align); > - vring_init(&vring, num, queue, vring_align); > + vring_split->queue_dma_addr = dma_addr; > + vring_split->queue_size_in_bytes = vring_size(num, vring_align); > + > + 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_virtqueue_split vring_split = {}; > + struct virtqueue *vq; > + int err; > + > + err = vring_alloc_queue_split(&vring_split, vdev, num, vring_align, > + may_reduce_num); > + if (err) > + return NULL; > > - vq = __vring_new_virtqueue(index, vring, vdev, weak_barriers, context, > - notify, callback, name); > + vq = __vring_new_virtqueue(index, vring_split.vring, vdev, weak_barriers, > + context, notify, callback, name); > if (!vq) { > - vring_free_queue(vdev, queue_size_in_bytes, queue, > - dma_addr); > + vring_free_split(&vring_split, vdev); > 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_split.queue_dma_addr; > + to_vvq(vq)->split.queue_size_in_bytes = vring_split.queue_size_in_bytes; This still seems a little bit redundant since the current logic is a little bit complicated since the vq->split is not initialized in a single place. I wonder if it's better to: vring_alloc_queue_split() vring_alloc_desc_extra() (reorder to make patch 9 come first) then we can simply assign vring_split to vq->split in __vring_new_virtqueue() since it has: vq->split.queue_dma_addr = 0; vq->split.queue_size_in_bytes = 0; vq->split.vring = vring; vq->split.avail_flags_shadow = 0; vq->split.avail_idx_shadow = 0; This seems to simplify the logic and task of e.g virtqueue_vring_attach_split() to a simple: vq->split= vring_split; And if this makes sense, we can do something similar to packed ring. Thanks > to_vvq(vq)->we_own_ring = true; > > return vq;
On Thu, 21 Jul 2022 17:13:49 +0800, Jason Wang <jasowang@redhat.com> wrote: > > 在 2022/7/20 11:04, Xuan Zhuo 写道: > > Separate the logic of split to create vring queue. > > > > This feature is required for subsequent virtuqueue reset vring. > > > > Signed-off-by: Xuan Zhuo <xuanzhuo@linux.alibaba.com> > > --- > > drivers/virtio/virtio_ring.c | 68 ++++++++++++++++++++++-------------- > > 1 file changed, 42 insertions(+), 26 deletions(-) > > > > diff --git a/drivers/virtio/virtio_ring.c b/drivers/virtio/virtio_ring.c > > index c94c5461e702..c7971438bb2c 100644 > > --- a/drivers/virtio/virtio_ring.c > > +++ b/drivers/virtio/virtio_ring.c > > @@ -950,28 +950,19 @@ static void vring_free_split(struct vring_virtqueue_split *vring_split, > > kfree(vring_split->desc_extra); > > } > > > > -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_alloc_queue_split(struct vring_virtqueue_split *vring_split, > > + struct virtio_device *vdev, > > + u32 num, > > + unsigned int vring_align, > > + bool may_reduce_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 */ > > @@ -982,11 +973,11 @@ 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! */ > > @@ -994,21 +985,46 @@ static struct virtqueue *vring_create_virtqueue_split( > > &dma_addr, GFP_KERNEL|__GFP_ZERO); > > } > > if (!queue) > > - return NULL; > > + return -ENOMEM; > > + > > + vring_init(&vring_split->vring, num, queue, vring_align); > > > > - queue_size_in_bytes = vring_size(num, vring_align); > > - vring_init(&vring, num, queue, vring_align); > > + vring_split->queue_dma_addr = dma_addr; > > + vring_split->queue_size_in_bytes = vring_size(num, vring_align); > > + > > + 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_virtqueue_split vring_split = {}; > > + struct virtqueue *vq; > > + int err; > > + > > + err = vring_alloc_queue_split(&vring_split, vdev, num, vring_align, > > + may_reduce_num); > > + if (err) > > + return NULL; > > > > - vq = __vring_new_virtqueue(index, vring, vdev, weak_barriers, context, > > - notify, callback, name); > > + vq = __vring_new_virtqueue(index, vring_split.vring, vdev, weak_barriers, > > + context, notify, callback, name); > > if (!vq) { > > - vring_free_queue(vdev, queue_size_in_bytes, queue, > > - dma_addr); > > + vring_free_split(&vring_split, vdev); > > 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_split.queue_dma_addr; > > + to_vvq(vq)->split.queue_size_in_bytes = vring_split.queue_size_in_bytes; > > > This still seems a little bit redundant since the current logic is a > little bit complicated since the vq->split is not initialized in a > single place. > > I wonder if it's better to: > > vring_alloc_queue_split() > vring_alloc_desc_extra() (reorder to make patch 9 come first) > > then we can simply assign vring_split to vq->split in > __vring_new_virtqueue() since it has: > > vq->split.queue_dma_addr = 0; > vq->split.queue_size_in_bytes = 0; > > vq->split.vring = vring; > vq->split.avail_flags_shadow = 0; > vq->split.avail_idx_shadow = 0; > > This seems to simplify the logic and task of e.g > virtqueue_vring_attach_split() to a simple: > > vq->split= vring_split; This does look simpler. The reason for not doing this is that the argument accepted by __vring_new_virtqueue() is "struct vring", and __vring_new_virtqueue() is an export symbol. I took a look, and the only external direct call to __vring_new_virtqueue is here. tools/virtio/virtio_test.c static void vq_reset(struct vq_info *info, int num, struct virtio_device *vdev) { if (info->vq) vring_del_virtqueue(info->vq); memset(info->ring, 0, vring_size(num, 4096)); vring_init(&info->vring, num, info->ring, 4096); info->vq = __vring_new_virtqueue(info->idx, info->vring, vdev, true, false, vq_notify, vq_callback, "test"); assert(info->vq); info->vq->priv = info; } I think this could be replaced with vring_new_virtqueue() so that we don't need to make __vring_new_virtqueue as an export function so we can make some modifications to it. nit: vring_alloc_desc_extra() should not have to be extract from __vring_new_virtqueue() . Thanks. > > And if this makes sense, we can do something similar to packed ring. > > Thanks > > > > to_vvq(vq)->we_own_ring = true; > > > > return vq; >
diff --git a/drivers/virtio/virtio_ring.c b/drivers/virtio/virtio_ring.c index c94c5461e702..c7971438bb2c 100644 --- a/drivers/virtio/virtio_ring.c +++ b/drivers/virtio/virtio_ring.c @@ -950,28 +950,19 @@ static void vring_free_split(struct vring_virtqueue_split *vring_split, kfree(vring_split->desc_extra); } -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_alloc_queue_split(struct vring_virtqueue_split *vring_split, + struct virtio_device *vdev, + u32 num, + unsigned int vring_align, + bool may_reduce_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 */ @@ -982,11 +973,11 @@ 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! */ @@ -994,21 +985,46 @@ static struct virtqueue *vring_create_virtqueue_split( &dma_addr, GFP_KERNEL|__GFP_ZERO); } if (!queue) - return NULL; + return -ENOMEM; + + vring_init(&vring_split->vring, num, queue, vring_align); - queue_size_in_bytes = vring_size(num, vring_align); - vring_init(&vring, num, queue, vring_align); + vring_split->queue_dma_addr = dma_addr; + vring_split->queue_size_in_bytes = vring_size(num, vring_align); + + 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_virtqueue_split vring_split = {}; + struct virtqueue *vq; + int err; + + err = vring_alloc_queue_split(&vring_split, vdev, num, vring_align, + may_reduce_num); + if (err) + return NULL; - vq = __vring_new_virtqueue(index, vring, vdev, weak_barriers, context, - notify, callback, name); + vq = __vring_new_virtqueue(index, vring_split.vring, vdev, weak_barriers, + context, notify, callback, name); if (!vq) { - vring_free_queue(vdev, queue_size_in_bytes, queue, - dma_addr); + vring_free_split(&vring_split, vdev); 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_split.queue_dma_addr; + to_vvq(vq)->split.queue_size_in_bytes = vring_split.queue_size_in_bytes; to_vvq(vq)->we_own_ring = true; return vq;
Separate the logic of split to create vring queue. This feature is required for subsequent virtuqueue reset vring. Signed-off-by: Xuan Zhuo <xuanzhuo@linux.alibaba.com> --- drivers/virtio/virtio_ring.c | 68 ++++++++++++++++++++++-------------- 1 file changed, 42 insertions(+), 26 deletions(-)