[PATCH v6 05/26] virtio_ring: split: extract the logic of init vq and attach vring
From: Xuan Zhuo <xuanzhuo@linux.alibaba.com>
Date: 2022-02-24 08:11:43
Also in:
bpf, kvm, linux-remoteproc, linux-s390, linux-um, platform-driver-x86, virtualization
Subsystem:
the rest, virtio core · Maintainers:
Linus Torvalds, "Michael S. Tsirkin", Jason Wang
Split the logic of split assignment vq into three parts. 1. The assignment passed from the function parameter 2. The part that attaches vring to vq. -- __vring_virtqueue_attach_split() 3. The part that initializes vq to a fixed value -- __vring_virtqueue_init_split() This feature is required for subsequent virtuqueue reset vring Signed-off-by: Xuan Zhuo <xuanzhuo@linux.alibaba.com> --- drivers/virtio/virtio_ring.c | 111 +++++++++++++++++++++-------------- 1 file changed, 67 insertions(+), 44 deletions(-)
diff --git a/drivers/virtio/virtio_ring.c b/drivers/virtio/virtio_ring.c
index d32793615451..dc6313b79305 100644
--- a/drivers/virtio/virtio_ring.c
+++ b/drivers/virtio/virtio_ring.c@@ -2196,34 +2196,40 @@ irqreturn_t vring_interrupt(int irq, void *_vq) } EXPORT_SYMBOL_GPL(vring_interrupt); -/* Only available for split ring */ -struct virtqueue *__vring_new_virtqueue(unsigned int index, - struct vring vring, - struct virtio_device *vdev, - bool weak_barriers, - bool context, - bool (*notify)(struct virtqueue *), - void (*callback)(struct virtqueue *), - const char *name) +static int __vring_virtqueue_attach_split(struct vring_virtqueue *vq, + struct virtio_device *vdev, + struct vring vring) { - struct vring_virtqueue *vq; + vq->vq.num_free = vring.num; - if (virtio_has_feature(vdev, VIRTIO_F_RING_PACKED)) - return NULL; + vq->split.vring = vring; + vq->split.queue_dma_addr = 0; + vq->split.queue_size_in_bytes = 0; - vq = kmalloc(sizeof(*vq), GFP_KERNEL); - if (!vq) - return NULL; + vq->split.desc_state = kmalloc_array(vring.num, + sizeof(struct vring_desc_state_split), GFP_KERNEL); + if (!vq->split.desc_state) + goto err_state; + vq->split.desc_extra = vring_alloc_desc_extra(vq, vring.num); + if (!vq->split.desc_extra) + goto err_extra; + + memset(vq->split.desc_state, 0, vring.num * + sizeof(struct vring_desc_state_split)); + return 0; + +err_extra: + kfree(vq->split.desc_state); +err_state: + return -ENOMEM; +} + +static void __vring_virtqueue_init_split(struct vring_virtqueue *vq, + struct virtio_device *vdev) +{ vq->packed_ring = false; - vq->vq.callback = callback; - vq->vq.vdev = vdev; - vq->vq.name = name; - vq->vq.num_free = vring.num; - vq->vq.index = index; vq->we_own_ring = false; - vq->notify = notify; - vq->weak_barriers = weak_barriers; vq->broken = false; vq->last_used_idx = 0; vq->event_triggered = false;
@@ -2234,50 +2240,67 @@ struct virtqueue *__vring_new_virtqueue(unsigned int index, vq->last_add_time_valid = false; #endif - vq->indirect = virtio_has_feature(vdev, VIRTIO_RING_F_INDIRECT_DESC) && - !context; vq->event = virtio_has_feature(vdev, VIRTIO_RING_F_EVENT_IDX); if (virtio_has_feature(vdev, VIRTIO_F_ORDER_PLATFORM)) vq->weak_barriers = false; - 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; /* No callback? Tell other side not to bother us. */ - if (!callback) { + if (!vq->vq.callback) { vq->split.avail_flags_shadow |= VRING_AVAIL_F_NO_INTERRUPT; if (!vq->event) vq->split.vring.avail->flags = cpu_to_virtio16(vdev, vq->split.avail_flags_shadow); } - vq->split.desc_state = kmalloc_array(vring.num, - sizeof(struct vring_desc_state_split), GFP_KERNEL); - if (!vq->split.desc_state) - goto err_state; - - vq->split.desc_extra = vring_alloc_desc_extra(vq, vring.num); - if (!vq->split.desc_extra) - goto err_extra; - /* Put everything in free lists. */ vq->free_head = 0; - memset(vq->split.desc_state, 0, vring.num * - sizeof(struct vring_desc_state_split)); +} + +/* Only available for split ring */ +struct virtqueue *__vring_new_virtqueue(unsigned int index, + struct vring vring, + struct virtio_device *vdev, + bool weak_barriers, + bool context, + bool (*notify)(struct virtqueue *), + void (*callback)(struct virtqueue *), + const char *name) +{ + struct vring_virtqueue *vq; + int err; + + if (virtio_has_feature(vdev, VIRTIO_F_RING_PACKED)) + return NULL; + + vq = kmalloc(sizeof(*vq), GFP_KERNEL); + if (!vq) + return NULL; + + vq->vq.callback = callback; + vq->vq.vdev = vdev; + vq->vq.name = name; + vq->vq.index = index; + vq->notify = notify; + vq->weak_barriers = weak_barriers; + vq->indirect = virtio_has_feature(vdev, VIRTIO_RING_F_INDIRECT_DESC) && + !context; + + err = __vring_virtqueue_attach_split(vq, vdev, vring); + if (err) + goto err; + + __vring_virtqueue_init_split(vq, vdev); spin_lock(&vdev->vqs_list_lock); list_add_tail(&vq->vq.list, &vdev->vqs); spin_unlock(&vdev->vqs_list_lock); - return &vq->vq; -err_extra: - kfree(vq->split.desc_state); -err_state: + return &vq->vq; +err: kfree(vq); return NULL; }
--
2.31.0