From 4a6fbf54cf6cdd0882624201bfefc4b1a033571b Mon Sep 17 00:00:00 2001 From: Tiwei Bie Date: Wed, 21 Nov 2018 18:03:27 +0800 Subject: [PATCH] virtio_ring: introduce packed ring support Introduce the packed ring support. Packed ring can only be created by vring_create_virtqueue() and each chunk of packed ring will be allocated individually. Packed ring can not be created on preallocated memory by vring_new_virtqueue() or the likes currently. Signed-off-by: Tiwei Bie Signed-off-by: David S. Miller --- drivers/virtio/virtio_ring.c | 900 +++++++++++++++++++++++++++++++++-- 1 file changed, 870 insertions(+), 30 deletions(-) diff --git a/drivers/virtio/virtio_ring.c b/drivers/virtio/virtio_ring.c index aafe1969b45e3..b63eee2034e78 100644 --- a/drivers/virtio/virtio_ring.c +++ b/drivers/virtio/virtio_ring.c @@ -83,9 +83,26 @@ struct vring_desc_state_split { struct vring_desc *indir_desc; /* Indirect descriptor, if any. */ }; +struct vring_desc_state_packed { + void *data; /* Data for callback. */ + struct vring_packed_desc *indir_desc; /* Indirect descriptor, if any. */ + u16 num; /* Descriptor list length. */ + u16 next; /* The next desc state in a list. */ + u16 last; /* The last desc state in a list. */ +}; + +struct vring_desc_extra_packed { + dma_addr_t addr; /* Buffer DMA addr. */ + u32 len; /* Buffer length. */ + u16 flags; /* Descriptor flags. */ +}; + struct vring_virtqueue { struct virtqueue vq; + /* Is this a packed ring? */ + bool packed_ring; + /* Is DMA API used? */ bool use_dma_api; @@ -109,23 +126,64 @@ struct vring_virtqueue { /* Last used index we've seen. */ u16 last_used_idx; - struct { - /* Actual memory layout for this queue */ - struct vring vring; + union { + /* Available for split ring */ + struct { + /* Actual memory layout for this queue. */ + struct vring vring; + + /* Last written value to avail->flags */ + u16 avail_flags_shadow; - /* Last written value to avail->flags */ - u16 avail_flags_shadow; + /* + * Last written value to avail->idx in + * guest byte order. + */ + u16 avail_idx_shadow; + + /* Per-descriptor state. */ + struct vring_desc_state_split *desc_state; + + /* DMA address and size information */ + dma_addr_t queue_dma_addr; + size_t queue_size_in_bytes; + } split; - /* Last written value to avail->idx in guest byte order */ - u16 avail_idx_shadow; + /* Available for packed ring */ + struct { + /* Actual memory layout for this queue. */ + struct vring_packed vring; - /* Per-descriptor state. */ - struct vring_desc_state_split *desc_state; + /* Driver ring wrap counter. */ + bool avail_wrap_counter; - /* DMA, allocation, and size information */ - size_t queue_size_in_bytes; - dma_addr_t queue_dma_addr; - } split; + /* Device ring wrap counter. */ + bool used_wrap_counter; + + /* Avail used flags. */ + u16 avail_used_flags; + + /* Index of the next avail descriptor. */ + u16 next_avail_idx; + + /* + * Last written value to driver->flags in + * guest byte order. + */ + u16 event_flags_shadow; + + /* Per-descriptor state. */ + struct vring_desc_state_packed *desc_state; + struct vring_desc_extra_packed *desc_extra; + + /* DMA address and size information */ + dma_addr_t ring_dma_addr; + dma_addr_t driver_event_dma_addr; + dma_addr_t device_event_dma_addr; + size_t ring_size_in_bytes; + size_t event_size_in_bytes; + } packed; + }; /* How to notify other side. FIXME: commonalize hcalls! */ bool (*notify)(struct virtqueue *vq); @@ -840,6 +898,717 @@ static struct virtqueue *vring_create_virtqueue_split( } +/* + * Packed ring specific functions - *_packed(). + */ + +static void vring_unmap_state_packed(const struct vring_virtqueue *vq, + struct vring_desc_extra_packed *state) +{ + u16 flags; + + if (!vq->use_dma_api) + return; + + flags = state->flags; + + if (flags & VRING_DESC_F_INDIRECT) { + dma_unmap_single(vring_dma_dev(vq), + state->addr, state->len, + (flags & VRING_DESC_F_WRITE) ? + DMA_FROM_DEVICE : DMA_TO_DEVICE); + } else { + dma_unmap_page(vring_dma_dev(vq), + state->addr, state->len, + (flags & VRING_DESC_F_WRITE) ? + DMA_FROM_DEVICE : DMA_TO_DEVICE); + } +} + +static void vring_unmap_desc_packed(const struct vring_virtqueue *vq, + struct vring_packed_desc *desc) +{ + u16 flags; + + if (!vq->use_dma_api) + return; + + flags = le16_to_cpu(desc->flags); + + if (flags & VRING_DESC_F_INDIRECT) { + dma_unmap_single(vring_dma_dev(vq), + le64_to_cpu(desc->addr), + le32_to_cpu(desc->len), + (flags & VRING_DESC_F_WRITE) ? + DMA_FROM_DEVICE : DMA_TO_DEVICE); + } else { + dma_unmap_page(vring_dma_dev(vq), + le64_to_cpu(desc->addr), + le32_to_cpu(desc->len), + (flags & VRING_DESC_F_WRITE) ? + DMA_FROM_DEVICE : DMA_TO_DEVICE); + } +} + +static struct vring_packed_desc *alloc_indirect_packed(unsigned int total_sg, + gfp_t gfp) +{ + struct vring_packed_desc *desc; + + /* + * We require lowmem mappings for the descriptors because + * otherwise virt_to_phys will give us bogus addresses in the + * virtqueue. + */ + gfp &= ~__GFP_HIGHMEM; + + desc = kmalloc_array(total_sg, sizeof(struct vring_packed_desc), gfp); + + return desc; +} + +static int virtqueue_add_indirect_packed(struct vring_virtqueue *vq, + struct scatterlist *sgs[], + unsigned int total_sg, + unsigned int out_sgs, + unsigned int in_sgs, + void *data, + gfp_t gfp) +{ + struct vring_packed_desc *desc; + struct scatterlist *sg; + unsigned int i, n, err_idx; + u16 head, id; + dma_addr_t addr; + + head = vq->packed.next_avail_idx; + desc = alloc_indirect_packed(total_sg, gfp); + + if (unlikely(vq->vq.num_free < 1)) { + pr_debug("Can't add buf len 1 - avail = 0\n"); + END_USE(vq); + return -ENOSPC; + } + + i = 0; + id = vq->free_head; + BUG_ON(id == vq->packed.vring.num); + + for (n = 0; n < out_sgs + in_sgs; n++) { + for (sg = sgs[n]; sg; sg = sg_next(sg)) { + addr = vring_map_one_sg(vq, sg, n < out_sgs ? + DMA_TO_DEVICE : DMA_FROM_DEVICE); + if (vring_mapping_error(vq, addr)) + goto unmap_release; + + desc[i].flags = cpu_to_le16(n < out_sgs ? + 0 : VRING_DESC_F_WRITE); + desc[i].addr = cpu_to_le64(addr); + desc[i].len = cpu_to_le32(sg->length); + i++; + } + } + + /* Now that the indirect table is filled in, map it. */ + addr = vring_map_single(vq, desc, + total_sg * sizeof(struct vring_packed_desc), + DMA_TO_DEVICE); + if (vring_mapping_error(vq, addr)) + goto unmap_release; + + vq->packed.vring.desc[head].addr = cpu_to_le64(addr); + vq->packed.vring.desc[head].len = cpu_to_le32(total_sg * + sizeof(struct vring_packed_desc)); + vq->packed.vring.desc[head].id = cpu_to_le16(id); + + if (vq->use_dma_api) { + vq->packed.desc_extra[id].addr = addr; + vq->packed.desc_extra[id].len = total_sg * + sizeof(struct vring_packed_desc); + vq->packed.desc_extra[id].flags = VRING_DESC_F_INDIRECT | + vq->packed.avail_used_flags; + } + + /* + * A driver MUST NOT make the first descriptor in the list + * available before all subsequent descriptors comprising + * the list are made available. + */ + virtio_wmb(vq->weak_barriers); + vq->packed.vring.desc[head].flags = cpu_to_le16(VRING_DESC_F_INDIRECT | + vq->packed.avail_used_flags); + + /* We're using some buffers from the free list. */ + vq->vq.num_free -= 1; + + /* Update free pointer */ + n = head + 1; + if (n >= vq->packed.vring.num) { + n = 0; + vq->packed.avail_wrap_counter ^= 1; + vq->packed.avail_used_flags ^= + 1 << VRING_PACKED_DESC_F_AVAIL | + 1 << VRING_PACKED_DESC_F_USED; + } + vq->packed.next_avail_idx = n; + vq->free_head = vq->packed.desc_state[id].next; + + /* Store token and indirect buffer state. */ + vq->packed.desc_state[id].num = 1; + vq->packed.desc_state[id].data = data; + vq->packed.desc_state[id].indir_desc = desc; + vq->packed.desc_state[id].last = id; + + vq->num_added += 1; + + pr_debug("Added buffer head %i to %p\n", head, vq); + END_USE(vq); + + return 0; + +unmap_release: + err_idx = i; + + for (i = 0; i < err_idx; i++) + vring_unmap_desc_packed(vq, &desc[i]); + + kfree(desc); + + END_USE(vq); + return -EIO; +} + +static inline int virtqueue_add_packed(struct virtqueue *_vq, + struct scatterlist *sgs[], + unsigned int total_sg, + unsigned int out_sgs, + unsigned int in_sgs, + void *data, + void *ctx, + gfp_t gfp) +{ + struct vring_virtqueue *vq = to_vvq(_vq); + struct vring_packed_desc *desc; + struct scatterlist *sg; + unsigned int i, n, c, descs_used, err_idx; + __le16 uninitialized_var(head_flags), flags; + u16 head, id, uninitialized_var(prev), curr, avail_used_flags; + + START_USE(vq); + + BUG_ON(data == NULL); + BUG_ON(ctx && vq->indirect); + + if (unlikely(vq->broken)) { + END_USE(vq); + return -EIO; + } + + LAST_ADD_TIME_UPDATE(vq); + + BUG_ON(total_sg == 0); + + if (virtqueue_use_indirect(_vq, total_sg)) + return virtqueue_add_indirect_packed(vq, sgs, total_sg, + out_sgs, in_sgs, data, gfp); + + head = vq->packed.next_avail_idx; + avail_used_flags = vq->packed.avail_used_flags; + + WARN_ON_ONCE(total_sg > vq->packed.vring.num && !vq->indirect); + + desc = vq->packed.vring.desc; + i = head; + descs_used = total_sg; + + if (unlikely(vq->vq.num_free < descs_used)) { + pr_debug("Can't add buf len %i - avail = %i\n", + descs_used, vq->vq.num_free); + END_USE(vq); + return -ENOSPC; + } + + id = vq->free_head; + BUG_ON(id == vq->packed.vring.num); + + curr = id; + c = 0; + for (n = 0; n < out_sgs + in_sgs; n++) { + for (sg = sgs[n]; sg; sg = sg_next(sg)) { + dma_addr_t addr = vring_map_one_sg(vq, sg, n < out_sgs ? + DMA_TO_DEVICE : DMA_FROM_DEVICE); + if (vring_mapping_error(vq, addr)) + goto unmap_release; + + flags = cpu_to_le16(vq->packed.avail_used_flags | + (++c == total_sg ? 0 : VRING_DESC_F_NEXT) | + (n < out_sgs ? 0 : VRING_DESC_F_WRITE)); + if (i == head) + head_flags = flags; + else + desc[i].flags = flags; + + desc[i].addr = cpu_to_le64(addr); + desc[i].len = cpu_to_le32(sg->length); + desc[i].id = cpu_to_le16(id); + + if (unlikely(vq->use_dma_api)) { + vq->packed.desc_extra[curr].addr = addr; + vq->packed.desc_extra[curr].len = sg->length; + vq->packed.desc_extra[curr].flags = + le16_to_cpu(flags); + } + prev = curr; + curr = vq->packed.desc_state[curr].next; + + if ((unlikely(++i >= vq->packed.vring.num))) { + i = 0; + vq->packed.avail_used_flags ^= + 1 << VRING_PACKED_DESC_F_AVAIL | + 1 << VRING_PACKED_DESC_F_USED; + } + } + } + + if (i < head) + vq->packed.avail_wrap_counter ^= 1; + + /* We're using some buffers from the free list. */ + vq->vq.num_free -= descs_used; + + /* Update free pointer */ + vq->packed.next_avail_idx = i; + vq->free_head = curr; + + /* Store token. */ + vq->packed.desc_state[id].num = descs_used; + vq->packed.desc_state[id].data = data; + vq->packed.desc_state[id].indir_desc = ctx; + vq->packed.desc_state[id].last = prev; + + /* + * A driver MUST NOT make the first descriptor in the list + * available before all subsequent descriptors comprising + * the list are made available. + */ + virtio_wmb(vq->weak_barriers); + vq->packed.vring.desc[head].flags = head_flags; + vq->num_added += descs_used; + + pr_debug("Added buffer head %i to %p\n", head, vq); + END_USE(vq); + + return 0; + +unmap_release: + err_idx = i; + i = head; + + vq->packed.avail_used_flags = avail_used_flags; + + for (n = 0; n < total_sg; n++) { + if (i == err_idx) + break; + vring_unmap_desc_packed(vq, &desc[i]); + i++; + if (i >= vq->packed.vring.num) + i = 0; + } + + END_USE(vq); + return -EIO; +} + +static bool virtqueue_kick_prepare_packed(struct virtqueue *_vq) +{ + struct vring_virtqueue *vq = to_vvq(_vq); + u16 flags; + bool needs_kick; + union { + struct { + __le16 off_wrap; + __le16 flags; + }; + u32 u32; + } snapshot; + + START_USE(vq); + + /* + * We need to expose the new flags value before checking notification + * suppressions. + */ + virtio_mb(vq->weak_barriers); + + vq->num_added = 0; + + snapshot.u32 = *(u32 *)vq->packed.vring.device; + flags = le16_to_cpu(snapshot.flags); + + LAST_ADD_TIME_CHECK(vq); + LAST_ADD_TIME_INVALID(vq); + + needs_kick = (flags != VRING_PACKED_EVENT_FLAG_DISABLE); + END_USE(vq); + return needs_kick; +} + +static void detach_buf_packed(struct vring_virtqueue *vq, + unsigned int id, void **ctx) +{ + struct vring_desc_state_packed *state = NULL; + struct vring_packed_desc *desc; + unsigned int i, curr; + + state = &vq->packed.desc_state[id]; + + /* Clear data ptr. */ + state->data = NULL; + + vq->packed.desc_state[state->last].next = vq->free_head; + vq->free_head = id; + vq->vq.num_free += state->num; + + if (unlikely(vq->use_dma_api)) { + curr = id; + for (i = 0; i < state->num; i++) { + vring_unmap_state_packed(vq, + &vq->packed.desc_extra[curr]); + curr = vq->packed.desc_state[curr].next; + } + } + + if (vq->indirect) { + u32 len; + + /* Free the indirect table, if any, now that it's unmapped. */ + desc = state->indir_desc; + if (!desc) + return; + + if (vq->use_dma_api) { + len = vq->packed.desc_extra[id].len; + for (i = 0; i < len / sizeof(struct vring_packed_desc); + i++) + vring_unmap_desc_packed(vq, &desc[i]); + } + kfree(desc); + state->indir_desc = NULL; + } else if (ctx) { + *ctx = state->indir_desc; + } +} + +static inline bool is_used_desc_packed(const struct vring_virtqueue *vq, + u16 idx, bool used_wrap_counter) +{ + bool avail, used; + u16 flags; + + flags = le16_to_cpu(vq->packed.vring.desc[idx].flags); + avail = !!(flags & (1 << VRING_PACKED_DESC_F_AVAIL)); + used = !!(flags & (1 << VRING_PACKED_DESC_F_USED)); + + return avail == used && used == used_wrap_counter; +} + +static inline bool more_used_packed(const struct vring_virtqueue *vq) +{ + return is_used_desc_packed(vq, vq->last_used_idx, + vq->packed.used_wrap_counter); +} + +static void *virtqueue_get_buf_ctx_packed(struct virtqueue *_vq, + unsigned int *len, + void **ctx) +{ + struct vring_virtqueue *vq = to_vvq(_vq); + u16 last_used, id; + void *ret; + + START_USE(vq); + + if (unlikely(vq->broken)) { + END_USE(vq); + return NULL; + } + + if (!more_used_packed(vq)) { + pr_debug("No more buffers in queue\n"); + END_USE(vq); + return NULL; + } + + /* Only get used elements after they have been exposed by host. */ + virtio_rmb(vq->weak_barriers); + + last_used = vq->last_used_idx; + id = le16_to_cpu(vq->packed.vring.desc[last_used].id); + *len = le32_to_cpu(vq->packed.vring.desc[last_used].len); + + if (unlikely(id >= vq->packed.vring.num)) { + BAD_RING(vq, "id %u out of range\n", id); + return NULL; + } + if (unlikely(!vq->packed.desc_state[id].data)) { + BAD_RING(vq, "id %u is not a head!\n", id); + return NULL; + } + + /* detach_buf_packed clears data, so grab it now. */ + ret = vq->packed.desc_state[id].data; + detach_buf_packed(vq, id, ctx); + + vq->last_used_idx += vq->packed.desc_state[id].num; + if (unlikely(vq->last_used_idx >= vq->packed.vring.num)) { + vq->last_used_idx -= vq->packed.vring.num; + vq->packed.used_wrap_counter ^= 1; + } + + LAST_ADD_TIME_INVALID(vq); + + END_USE(vq); + return ret; +} + +static void virtqueue_disable_cb_packed(struct virtqueue *_vq) +{ + struct vring_virtqueue *vq = to_vvq(_vq); + + if (vq->packed.event_flags_shadow != VRING_PACKED_EVENT_FLAG_DISABLE) { + vq->packed.event_flags_shadow = VRING_PACKED_EVENT_FLAG_DISABLE; + vq->packed.vring.driver->flags = + cpu_to_le16(vq->packed.event_flags_shadow); + } +} + +static unsigned virtqueue_enable_cb_prepare_packed(struct virtqueue *_vq) +{ + struct vring_virtqueue *vq = to_vvq(_vq); + + START_USE(vq); + + /* + * We optimistically turn back on interrupts, then check if there was + * more to do. + */ + + if (vq->packed.event_flags_shadow == VRING_PACKED_EVENT_FLAG_DISABLE) { + vq->packed.event_flags_shadow = VRING_PACKED_EVENT_FLAG_ENABLE; + vq->packed.vring.driver->flags = + cpu_to_le16(vq->packed.event_flags_shadow); + } + + END_USE(vq); + return vq->last_used_idx | ((u16)vq->packed.used_wrap_counter << + VRING_PACKED_EVENT_F_WRAP_CTR); +} + +static bool virtqueue_poll_packed(struct virtqueue *_vq, u16 off_wrap) +{ + struct vring_virtqueue *vq = to_vvq(_vq); + bool wrap_counter; + u16 used_idx; + + wrap_counter = off_wrap >> VRING_PACKED_EVENT_F_WRAP_CTR; + used_idx = off_wrap & ~(1 << VRING_PACKED_EVENT_F_WRAP_CTR); + + return is_used_desc_packed(vq, used_idx, wrap_counter); +} + +static bool virtqueue_enable_cb_delayed_packed(struct virtqueue *_vq) +{ + struct vring_virtqueue *vq = to_vvq(_vq); + u16 used_idx, wrap_counter; + + START_USE(vq); + + /* + * We optimistically turn back on interrupts, then check if there was + * more to do. + */ + + used_idx = vq->last_used_idx; + wrap_counter = vq->packed.used_wrap_counter; + + if (vq->packed.event_flags_shadow == VRING_PACKED_EVENT_FLAG_DISABLE) { + vq->packed.event_flags_shadow = VRING_PACKED_EVENT_FLAG_ENABLE; + vq->packed.vring.driver->flags = + cpu_to_le16(vq->packed.event_flags_shadow); + } + + /* + * We need to update event suppression structure first + * before re-checking for more used buffers. + */ + virtio_mb(vq->weak_barriers); + + if (is_used_desc_packed(vq, used_idx, wrap_counter)) { + END_USE(vq); + return false; + } + + END_USE(vq); + return true; +} + +static void *virtqueue_detach_unused_buf_packed(struct virtqueue *_vq) +{ + struct vring_virtqueue *vq = to_vvq(_vq); + unsigned int i; + void *buf; + + START_USE(vq); + + for (i = 0; i < vq->packed.vring.num; i++) { + if (!vq->packed.desc_state[i].data) + continue; + /* detach_buf clears data, so grab it now. */ + buf = vq->packed.desc_state[i].data; + detach_buf_packed(vq, i, NULL); + END_USE(vq); + return buf; + } + /* That should have freed everything. */ + BUG_ON(vq->vq.num_free != vq->packed.vring.num); + + END_USE(vq); + return NULL; +} + +static struct virtqueue *vring_create_virtqueue_packed( + 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 *vq; + struct vring_packed_desc *ring; + struct vring_packed_desc_event *driver, *device; + dma_addr_t ring_dma_addr, driver_event_dma_addr, device_event_dma_addr; + size_t ring_size_in_bytes, event_size_in_bytes; + unsigned int i; + + ring_size_in_bytes = num * sizeof(struct vring_packed_desc); + + ring = vring_alloc_queue(vdev, ring_size_in_bytes, + &ring_dma_addr, + GFP_KERNEL|__GFP_NOWARN|__GFP_ZERO); + if (!ring) + goto err_ring; + + event_size_in_bytes = sizeof(struct vring_packed_desc_event); + + driver = vring_alloc_queue(vdev, event_size_in_bytes, + &driver_event_dma_addr, + GFP_KERNEL|__GFP_NOWARN|__GFP_ZERO); + if (!driver) + goto err_driver; + + device = vring_alloc_queue(vdev, event_size_in_bytes, + &device_event_dma_addr, + GFP_KERNEL|__GFP_NOWARN|__GFP_ZERO); + if (!device) + goto err_device; + + vq = kmalloc(sizeof(*vq), GFP_KERNEL); + if (!vq) + goto err_vq; + + vq->vq.callback = callback; + vq->vq.vdev = vdev; + vq->vq.name = name; + vq->vq.num_free = num; + vq->vq.index = index; + vq->we_own_ring = true; + vq->notify = notify; + vq->weak_barriers = weak_barriers; + vq->broken = false; + vq->last_used_idx = 0; + vq->num_added = 0; + vq->packed_ring = true; + vq->use_dma_api = vring_use_dma_api(vdev); + list_add_tail(&vq->vq.list, &vdev->vqs); +#ifdef DEBUG + vq->in_use = false; + 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); + + vq->packed.ring_dma_addr = ring_dma_addr; + vq->packed.driver_event_dma_addr = driver_event_dma_addr; + vq->packed.device_event_dma_addr = device_event_dma_addr; + + vq->packed.ring_size_in_bytes = ring_size_in_bytes; + vq->packed.event_size_in_bytes = event_size_in_bytes; + + vq->packed.vring.num = num; + vq->packed.vring.desc = ring; + vq->packed.vring.driver = driver; + vq->packed.vring.device = device; + + vq->packed.next_avail_idx = 0; + vq->packed.avail_wrap_counter = 1; + vq->packed.used_wrap_counter = 1; + vq->packed.event_flags_shadow = 0; + vq->packed.avail_used_flags = 1 << VRING_PACKED_DESC_F_AVAIL; + + vq->packed.desc_state = kmalloc_array(num, + sizeof(struct vring_desc_state_packed), + GFP_KERNEL); + if (!vq->packed.desc_state) + goto err_desc_state; + + memset(vq->packed.desc_state, 0, + num * sizeof(struct vring_desc_state_packed)); + + /* Put everything in free lists. */ + vq->free_head = 0; + for (i = 0; i < num-1; i++) + vq->packed.desc_state[i].next = i + 1; + + vq->packed.desc_extra = kmalloc_array(num, + sizeof(struct vring_desc_extra_packed), + GFP_KERNEL); + if (!vq->packed.desc_extra) + goto err_desc_extra; + + memset(vq->packed.desc_extra, 0, + num * sizeof(struct vring_desc_extra_packed)); + + /* No callback? Tell other side not to bother us. */ + if (!callback) { + vq->packed.event_flags_shadow = VRING_PACKED_EVENT_FLAG_DISABLE; + vq->packed.vring.driver->flags = + cpu_to_le16(vq->packed.event_flags_shadow); + } + + return &vq->vq; + +err_desc_extra: + kfree(vq->packed.desc_state); +err_desc_state: + kfree(vq); +err_vq: + vring_free_queue(vdev, event_size_in_bytes, device, ring_dma_addr); +err_device: + vring_free_queue(vdev, event_size_in_bytes, driver, ring_dma_addr); +err_driver: + vring_free_queue(vdev, ring_size_in_bytes, ring, ring_dma_addr); +err_ring: + return NULL; +} + + /* * Generic functions and exported symbols. */ @@ -853,8 +1622,12 @@ static inline int virtqueue_add(struct virtqueue *_vq, void *ctx, gfp_t gfp) { - return virtqueue_add_split(_vq, sgs, total_sg, - out_sgs, in_sgs, data, ctx, gfp); + struct vring_virtqueue *vq = to_vvq(_vq); + + return vq->packed_ring ? virtqueue_add_packed(_vq, sgs, total_sg, + out_sgs, in_sgs, data, ctx, gfp) : + virtqueue_add_split(_vq, sgs, total_sg, + out_sgs, in_sgs, data, ctx, gfp); } /** @@ -973,7 +1746,10 @@ EXPORT_SYMBOL_GPL(virtqueue_add_inbuf_ctx); */ bool virtqueue_kick_prepare(struct virtqueue *_vq) { - return virtqueue_kick_prepare_split(_vq); + struct vring_virtqueue *vq = to_vvq(_vq); + + return vq->packed_ring ? virtqueue_kick_prepare_packed(_vq) : + virtqueue_kick_prepare_split(_vq); } EXPORT_SYMBOL_GPL(virtqueue_kick_prepare); @@ -1040,7 +1816,10 @@ EXPORT_SYMBOL_GPL(virtqueue_kick); void *virtqueue_get_buf_ctx(struct virtqueue *_vq, unsigned int *len, void **ctx) { - return virtqueue_get_buf_ctx_split(_vq, len, ctx); + struct vring_virtqueue *vq = to_vvq(_vq); + + return vq->packed_ring ? virtqueue_get_buf_ctx_packed(_vq, len, ctx) : + virtqueue_get_buf_ctx_split(_vq, len, ctx); } EXPORT_SYMBOL_GPL(virtqueue_get_buf_ctx); @@ -1049,7 +1828,6 @@ void *virtqueue_get_buf(struct virtqueue *_vq, unsigned int *len) return virtqueue_get_buf_ctx(_vq, len, NULL); } EXPORT_SYMBOL_GPL(virtqueue_get_buf); - /** * virtqueue_disable_cb - disable callbacks * @vq: the struct virtqueue we're talking about. @@ -1061,7 +1839,12 @@ EXPORT_SYMBOL_GPL(virtqueue_get_buf); */ void virtqueue_disable_cb(struct virtqueue *_vq) { - virtqueue_disable_cb_split(_vq); + struct vring_virtqueue *vq = to_vvq(_vq); + + if (vq->packed_ring) + virtqueue_disable_cb_packed(_vq); + else + virtqueue_disable_cb_split(_vq); } EXPORT_SYMBOL_GPL(virtqueue_disable_cb); @@ -1079,7 +1862,10 @@ EXPORT_SYMBOL_GPL(virtqueue_disable_cb); */ unsigned virtqueue_enable_cb_prepare(struct virtqueue *_vq) { - return virtqueue_enable_cb_prepare_split(_vq); + struct vring_virtqueue *vq = to_vvq(_vq); + + return vq->packed_ring ? virtqueue_enable_cb_prepare_packed(_vq) : + virtqueue_enable_cb_prepare_split(_vq); } EXPORT_SYMBOL_GPL(virtqueue_enable_cb_prepare); @@ -1097,7 +1883,8 @@ bool virtqueue_poll(struct virtqueue *_vq, unsigned last_used_idx) struct vring_virtqueue *vq = to_vvq(_vq); virtio_mb(vq->weak_barriers); - return virtqueue_poll_split(_vq, last_used_idx); + return vq->packed_ring ? virtqueue_poll_packed(_vq, last_used_idx) : + virtqueue_poll_split(_vq, last_used_idx); } EXPORT_SYMBOL_GPL(virtqueue_poll); @@ -1135,7 +1922,10 @@ EXPORT_SYMBOL_GPL(virtqueue_enable_cb); */ bool virtqueue_enable_cb_delayed(struct virtqueue *_vq) { - return virtqueue_enable_cb_delayed_split(_vq); + struct vring_virtqueue *vq = to_vvq(_vq); + + return vq->packed_ring ? virtqueue_enable_cb_delayed_packed(_vq) : + virtqueue_enable_cb_delayed_split(_vq); } EXPORT_SYMBOL_GPL(virtqueue_enable_cb_delayed); @@ -1149,13 +1939,16 @@ EXPORT_SYMBOL_GPL(virtqueue_enable_cb_delayed); */ void *virtqueue_detach_unused_buf(struct virtqueue *_vq) { - return virtqueue_detach_unused_buf_split(_vq); + struct vring_virtqueue *vq = to_vvq(_vq); + + return vq->packed_ring ? virtqueue_detach_unused_buf_packed(_vq) : + virtqueue_detach_unused_buf_split(_vq); } EXPORT_SYMBOL_GPL(virtqueue_detach_unused_buf); static inline bool more_used(const struct vring_virtqueue *vq) { - return more_used_split(vq); + return vq->packed_ring ? more_used_packed(vq) : more_used_split(vq); } irqreturn_t vring_interrupt(int irq, void *_vq) @@ -1178,6 +1971,7 @@ 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, @@ -1190,10 +1984,14 @@ struct virtqueue *__vring_new_virtqueue(unsigned int index, unsigned int i; struct vring_virtqueue *vq; + if (virtio_has_feature(vdev, VIRTIO_F_RING_PACKED)) + return NULL; + vq = kmalloc(sizeof(*vq), GFP_KERNEL); if (!vq) return NULL; + vq->packed_ring = false; vq->vq.callback = callback; vq->vq.vdev = vdev; vq->vq.name = name; @@ -1261,12 +2059,19 @@ struct virtqueue *vring_create_virtqueue( void (*callback)(struct virtqueue *), const char *name) { + + if (virtio_has_feature(vdev, VIRTIO_F_RING_PACKED)) + return vring_create_virtqueue_packed(index, num, vring_align, + vdev, weak_barriers, may_reduce_num, + context, notify, callback, name); + return vring_create_virtqueue_split(index, num, vring_align, vdev, weak_barriers, may_reduce_num, context, notify, callback, name); } EXPORT_SYMBOL_GPL(vring_create_virtqueue); +/* Only available for split ring */ struct virtqueue *vring_new_virtqueue(unsigned int index, unsigned int num, unsigned int vring_align, @@ -1279,6 +2084,10 @@ struct virtqueue *vring_new_virtqueue(unsigned int index, const char *name) { struct vring vring; + + if (virtio_has_feature(vdev, VIRTIO_F_RING_PACKED)) + return NULL; + vring_init(&vring, num, pages, vring_align); return __vring_new_virtqueue(index, vring, vdev, weak_barriers, context, notify, callback, name); @@ -1290,11 +2099,32 @@ void vring_del_virtqueue(struct virtqueue *_vq) struct vring_virtqueue *vq = to_vvq(_vq); if (vq->we_own_ring) { - vring_free_queue(vq->vq.vdev, - vq->split.queue_size_in_bytes, - vq->split.vring.desc, - vq->split.queue_dma_addr); - kfree(vq->split.desc_state); + if (vq->packed_ring) { + vring_free_queue(vq->vq.vdev, + vq->packed.ring_size_in_bytes, + vq->packed.vring.desc, + vq->packed.ring_dma_addr); + + vring_free_queue(vq->vq.vdev, + vq->packed.event_size_in_bytes, + vq->packed.vring.driver, + vq->packed.driver_event_dma_addr); + + vring_free_queue(vq->vq.vdev, + vq->packed.event_size_in_bytes, + vq->packed.vring.device, + vq->packed.device_event_dma_addr); + + kfree(vq->packed.desc_state); + kfree(vq->packed.desc_extra); + } else { + vring_free_queue(vq->vq.vdev, + vq->split.queue_size_in_bytes, + vq->split.vring.desc, + vq->split.queue_dma_addr); + + kfree(vq->split.desc_state); + } } list_del(&_vq->list); kfree(vq); @@ -1336,7 +2166,7 @@ unsigned int virtqueue_get_vring_size(struct virtqueue *_vq) struct vring_virtqueue *vq = to_vvq(_vq); - return vq->split.vring.num; + return vq->packed_ring ? vq->packed.vring.num : vq->split.vring.num; } EXPORT_SYMBOL_GPL(virtqueue_get_vring_size); @@ -1369,6 +2199,9 @@ dma_addr_t virtqueue_get_desc_addr(struct virtqueue *_vq) BUG_ON(!vq->we_own_ring); + if (vq->packed_ring) + return vq->packed.ring_dma_addr; + return vq->split.queue_dma_addr; } EXPORT_SYMBOL_GPL(virtqueue_get_desc_addr); @@ -1379,6 +2212,9 @@ dma_addr_t virtqueue_get_avail_addr(struct virtqueue *_vq) BUG_ON(!vq->we_own_ring); + if (vq->packed_ring) + return vq->packed.driver_event_dma_addr; + return vq->split.queue_dma_addr + ((char *)vq->split.vring.avail - (char *)vq->split.vring.desc); } @@ -1390,11 +2226,15 @@ dma_addr_t virtqueue_get_used_addr(struct virtqueue *_vq) BUG_ON(!vq->we_own_ring); + if (vq->packed_ring) + return vq->packed.device_event_dma_addr; + return vq->split.queue_dma_addr + ((char *)vq->split.vring.used - (char *)vq->split.vring.desc); } EXPORT_SYMBOL_GPL(virtqueue_get_used_addr); +/* Only available for split ring */ const struct vring *virtqueue_get_vring(struct virtqueue *vq) { return &to_vvq(vq)->split.vring; -- 2.39.5