Use translations added in VhostIOVATree in SVQ. Now every element needs to store the previous address also, so VirtQueue can consume the elements properly. This adds a little overhead per VQ element, having to allocate more memory to stash them. As a possible optimization, this allocation could be avoided if the descriptor is not a chain but a single one, but this is left undone.
TODO: iova range should be queried before, and add logic to fail when GPA is outside of its range and memory listener or svq add it. Signed-off-by: Eugenio Pérez <[email protected]> --- hw/virtio/vhost-shadow-virtqueue.h | 4 +- hw/virtio/vhost-shadow-virtqueue.c | 130 ++++++++++++++++++++++++----- hw/virtio/vhost-vdpa.c | 40 ++++++++- hw/virtio/trace-events | 1 + 4 files changed, 152 insertions(+), 23 deletions(-) diff --git a/hw/virtio/vhost-shadow-virtqueue.h b/hw/virtio/vhost-shadow-virtqueue.h index b7baa424a7..a0e6b5267a 100644 --- a/hw/virtio/vhost-shadow-virtqueue.h +++ b/hw/virtio/vhost-shadow-virtqueue.h @@ -11,6 +11,7 @@ #define VHOST_SHADOW_VIRTQUEUE_H #include "hw/virtio/vhost.h" +#include "hw/virtio/vhost-iova-tree.h" typedef struct VhostShadowVirtqueue VhostShadowVirtqueue; @@ -28,7 +29,8 @@ bool vhost_svq_start(struct vhost_dev *dev, unsigned idx, void vhost_svq_stop(struct vhost_dev *dev, unsigned idx, VhostShadowVirtqueue *svq); -VhostShadowVirtqueue *vhost_svq_new(struct vhost_dev *dev, int idx); +VhostShadowVirtqueue *vhost_svq_new(struct vhost_dev *dev, int idx, + VhostIOVATree *iova_map); void vhost_svq_free(VhostShadowVirtqueue *vq); diff --git a/hw/virtio/vhost-shadow-virtqueue.c b/hw/virtio/vhost-shadow-virtqueue.c index 2fd0bab75d..9db538547e 100644 --- a/hw/virtio/vhost-shadow-virtqueue.c +++ b/hw/virtio/vhost-shadow-virtqueue.c @@ -11,12 +11,19 @@ #include "hw/virtio/vhost-shadow-virtqueue.h" #include "hw/virtio/vhost.h" #include "hw/virtio/virtio-access.h" +#include "hw/virtio/vhost-iova-tree.h" #include "standard-headers/linux/vhost_types.h" #include "qemu/error-report.h" #include "qemu/main-loop.h" +typedef struct SVQElement { + VirtQueueElement elem; + void **in_sg_stash; + void **out_sg_stash; +} SVQElement; + /* Shadow virtqueue to relay notifications */ typedef struct VhostShadowVirtqueue { /* Shadow vring */ @@ -46,8 +53,11 @@ typedef struct VhostShadowVirtqueue { /* Virtio device */ VirtIODevice *vdev; + /* IOVA mapping if used */ + VhostIOVATree *iova_map; + /* Map for returning guest's descriptors */ - VirtQueueElement **ring_id_maps; + SVQElement **ring_id_maps; /* Next head to expose to device */ uint16_t avail_idx_shadow; @@ -79,13 +89,6 @@ bool vhost_svq_valid_device_features(uint64_t *dev_features) continue; case VIRTIO_F_ACCESS_PLATFORM: - /* SVQ needs this feature disabled. Can't continue */ - if (*dev_features & BIT_ULL(b)) { - clear_bit(b, dev_features); - r = false; - } - break; - case VIRTIO_F_VERSION_1: /* SVQ needs this feature, so can't continue */ if (!(*dev_features & BIT_ULL(b))) { @@ -126,6 +129,64 @@ static void vhost_svq_set_notification(VhostShadowVirtqueue *svq, bool enable) } } +static void vhost_svq_stash_addr(void ***stash, const struct iovec *iov, + size_t num) +{ + size_t i; + + if (num == 0) { + return; + } + + *stash = g_new(void *, num); + for (i = 0; i < num; ++i) { + (*stash)[i] = iov[i].iov_base; + } +} + +static void vhost_svq_unstash_addr(void **stash, struct iovec *iov, size_t num) +{ + size_t i; + + if (num == 0) { + return; + } + + for (i = 0; i < num; ++i) { + iov[i].iov_base = stash[i]; + } + g_free(stash); +} + +static void vhost_svq_translate_addr(const VhostShadowVirtqueue *svq, + struct iovec *iovec, size_t num) +{ + size_t i; + + for (i = 0; i < num; ++i) { + VhostDMAMap needle = { + .translated_addr = iovec[i].iov_base, + .size = iovec[i].iov_len, + }; + size_t off; + + const VhostDMAMap *map = vhost_iova_tree_find_iova(svq->iova_map, + &needle); + /* + * Map cannot be NULL since iova map contains all guest space and + * qemu already has a physical address mapped + */ + assert(map); + + /* + * Map->iova chunk size is ignored. What to do if descriptor + * (addr, size) does not fit is delegated to the device. + */ + off = needle.translated_addr - map->translated_addr; + iovec[i].iov_base = (void *)(map->iova + off); + } +} + static void vhost_vring_write_descs(VhostShadowVirtqueue *svq, const struct iovec *iovec, size_t num, bool more_descs, bool write) @@ -156,8 +217,9 @@ static void vhost_vring_write_descs(VhostShadowVirtqueue *svq, } static unsigned vhost_svq_add_split(VhostShadowVirtqueue *svq, - VirtQueueElement *elem) + SVQElement *svq_elem) { + VirtQueueElement *elem = &svq_elem->elem; int head; unsigned avail_idx; vring_avail_t *avail = svq->vring.avail; @@ -167,6 +229,12 @@ static unsigned vhost_svq_add_split(VhostShadowVirtqueue *svq, /* We need some descriptors here */ assert(elem->out_num || elem->in_num); + vhost_svq_stash_addr(&svq_elem->in_sg_stash, elem->in_sg, elem->in_num); + vhost_svq_stash_addr(&svq_elem->out_sg_stash, elem->out_sg, elem->out_num); + + vhost_svq_translate_addr(svq, elem->in_sg, elem->in_num); + vhost_svq_translate_addr(svq, elem->out_sg, elem->out_num); + vhost_vring_write_descs(svq, elem->out_sg, elem->out_num, elem->in_num > 0, false); vhost_vring_write_descs(svq, elem->in_sg, elem->in_num, false, true); @@ -187,7 +255,7 @@ static unsigned vhost_svq_add_split(VhostShadowVirtqueue *svq, } -static void vhost_svq_add(VhostShadowVirtqueue *svq, VirtQueueElement *elem) +static void vhost_svq_add(VhostShadowVirtqueue *svq, SVQElement *elem) { unsigned qemu_head = vhost_svq_add_split(svq, elem); @@ -221,7 +289,7 @@ static void vhost_handle_guest_kick(EventNotifier *n) } while (true) { - VirtQueueElement *elem = virtqueue_pop(svq->vq, sizeof(*elem)); + SVQElement *elem = virtqueue_pop(svq->vq, sizeof(*elem)); if (!elem) { break; } @@ -247,7 +315,7 @@ static bool vhost_svq_more_used(VhostShadowVirtqueue *svq) return svq->used_idx != svq->shadow_used_idx; } -static VirtQueueElement *vhost_svq_get_buf(VhostShadowVirtqueue *svq) +static SVQElement *vhost_svq_get_buf(VhostShadowVirtqueue *svq) { vring_desc_t *descs = svq->vring.desc; const vring_used_t *used = svq->vring.used; @@ -279,7 +347,7 @@ static VirtQueueElement *vhost_svq_get_buf(VhostShadowVirtqueue *svq) descs[used_elem.id].next = svq->free_head; svq->free_head = used_elem.id; - svq->ring_id_maps[used_elem.id]->len = used_elem.len; + svq->ring_id_maps[used_elem.id]->elem.len = used_elem.len; return g_steal_pointer(&svq->ring_id_maps[used_elem.id]); } @@ -296,12 +364,19 @@ static void vhost_svq_handle_call_no_test(EventNotifier *n) vhost_svq_set_notification(svq, false); while (true) { - g_autofree VirtQueueElement *elem = vhost_svq_get_buf(svq); - if (!elem) { + g_autofree SVQElement *svq_elem = vhost_svq_get_buf(svq); + VirtQueueElement *elem; + if (!svq_elem) { break; } assert(i < svq->vring.num); + elem = &svq_elem->elem; + + vhost_svq_unstash_addr(svq_elem->in_sg_stash, elem->in_sg, + elem->in_num); + vhost_svq_unstash_addr(svq_elem->out_sg_stash, elem->out_sg, + elem->out_num); virtqueue_fill(vq, elem, elem->len, i++); } @@ -451,14 +526,24 @@ void vhost_svq_stop(struct vhost_dev *dev, unsigned idx, event_notifier_set_handler(&svq->host_notifier, NULL); for (i = 0; i < svq->vring.num; ++i) { - g_autofree VirtQueueElement *elem = svq->ring_id_maps[i]; + g_autofree SVQElement *svq_elem = svq->ring_id_maps[i]; + VirtQueueElement *elem; + + if (!svq_elem) { + continue; + } + + elem = &svq_elem->elem; + vhost_svq_unstash_addr(svq_elem->in_sg_stash, elem->in_sg, + elem->in_num); + vhost_svq_unstash_addr(svq_elem->out_sg_stash, elem->out_sg, + elem->out_num); + /* * Although the doc says we must unpop in order, it's ok to unpop * everything. */ - if (elem) { - virtqueue_unpop(svq->vq, elem, elem->len); - } + virtqueue_unpop(svq->vq, elem, elem->len); } } @@ -466,7 +551,8 @@ void vhost_svq_stop(struct vhost_dev *dev, unsigned idx, * Creates vhost shadow virtqueue, and instruct vhost device to use the shadow * methods and file descriptors. */ -VhostShadowVirtqueue *vhost_svq_new(struct vhost_dev *dev, int idx) +VhostShadowVirtqueue *vhost_svq_new(struct vhost_dev *dev, int idx, + VhostIOVATree *iova_map) { int vq_idx = dev->vq_index + idx; unsigned num = virtio_queue_get_num(dev->vdev, vq_idx); @@ -500,11 +586,13 @@ VhostShadowVirtqueue *vhost_svq_new(struct vhost_dev *dev, int idx) memset(svq->vring.desc, 0, driver_size); svq->vring.used = qemu_memalign(qemu_real_host_page_size, device_size); memset(svq->vring.used, 0, device_size); + svq->iova_map = iova_map; + for (i = 0; i < num - 1; i++) { svq->vring.desc[i].next = cpu_to_le16(i + 1); } - svq->ring_id_maps = g_new0(VirtQueueElement *, num); + svq->ring_id_maps = g_new0(SVQElement *, num); event_notifier_set_handler(&svq->call_notifier, vhost_svq_handle_call); return g_steal_pointer(&svq); diff --git a/hw/virtio/vhost-vdpa.c b/hw/virtio/vhost-vdpa.c index a9c680b487..f5a12fee9d 100644 --- a/hw/virtio/vhost-vdpa.c +++ b/hw/virtio/vhost-vdpa.c @@ -176,6 +176,18 @@ static void vhost_vdpa_listener_region_add(MemoryListener *listener, vaddr, section->readonly); llsize = int128_sub(llend, int128_make64(iova)); + if (v->shadow_vqs_enabled) { + VhostDMAMap mem_region = { + .translated_addr = vaddr, + .size = int128_get64(llsize) - 1, + .perm = IOMMU_ACCESS_FLAG(true, section->readonly), + }; + + int r = vhost_iova_tree_alloc(v->iova_map, &mem_region); + assert(r == VHOST_DMA_MAP_OK); + + iova = mem_region.iova; + } ret = vhost_vdpa_dma_map(v, iova, int128_get64(llsize), vaddr, section->readonly); @@ -754,6 +766,23 @@ static bool vhost_vdpa_force_iommu(struct vhost_dev *dev) return true; } +static int vhost_vdpa_get_iova_range(struct vhost_dev *dev, + hwaddr *first, hwaddr *last) +{ + int ret; + struct vhost_vdpa_iova_range range; + + ret = vhost_vdpa_call(dev, VHOST_VDPA_GET_IOVA_RANGE, &range); + if (ret != 0) { + return ret; + } + + *first = range.first; + *last = range.last; + trace_vhost_vdpa_get_iova_range(dev, *first, *last); + return ret; +} + /** * Maps QEMU vaddr memory to device in a suitable way for shadow virtqueue: * - It always reference qemu memory address, not guest's memory. @@ -881,6 +910,7 @@ static bool vhost_vdpa_svq_start_vq(struct vhost_dev *dev, unsigned idx) static unsigned vhost_vdpa_enable_svq(struct vhost_vdpa *v, bool enable) { struct vhost_dev *hdev = v->dev; + hwaddr iova_first, iova_last; unsigned n; int r; @@ -894,7 +924,7 @@ static unsigned vhost_vdpa_enable_svq(struct vhost_vdpa *v, bool enable) /* Allocate resources */ assert(v->shadow_vqs->len == 0); for (n = 0; n < hdev->nvqs; ++n) { - VhostShadowVirtqueue *svq = vhost_svq_new(hdev, n); + VhostShadowVirtqueue *svq = vhost_svq_new(hdev, n, v->iova_map); if (unlikely(!svq)) { g_ptr_array_set_size(v->shadow_vqs, 0); return 0; @@ -903,6 +933,8 @@ static unsigned vhost_vdpa_enable_svq(struct vhost_vdpa *v, bool enable) } } + r = vhost_vdpa_get_iova_range(hdev, &iova_first, &iova_last); + assert(r == 0); r = vhost_vdpa_vring_pause(hdev); assert(r == 0); @@ -913,6 +945,12 @@ static unsigned vhost_vdpa_enable_svq(struct vhost_vdpa *v, bool enable) } } + memory_listener_unregister(&v->listener); + if (vhost_vdpa_dma_unmap(v, iova_first, + (iova_last - iova_first) & TARGET_PAGE_MASK)) { + error_report("Fail to invalidate device iotlb"); + } + /* Reset device so it can be configured */ r = vhost_vdpa_dev_start(hdev, false); assert(r == 0); diff --git a/hw/virtio/trace-events b/hw/virtio/trace-events index 8ed19e9d0c..650e521e35 100644 --- a/hw/virtio/trace-events +++ b/hw/virtio/trace-events @@ -52,6 +52,7 @@ vhost_vdpa_set_vring_call(void *dev, unsigned int index, int fd) "dev: %p index: vhost_vdpa_get_features(void *dev, uint64_t features) "dev: %p features: 0x%"PRIx64 vhost_vdpa_set_owner(void *dev) "dev: %p" vhost_vdpa_vq_get_addr(void *dev, void *vq, uint64_t desc_user_addr, uint64_t avail_user_addr, uint64_t used_user_addr) "dev: %p vq: %p desc_user_addr: 0x%"PRIx64" avail_user_addr: 0x%"PRIx64" used_user_addr: 0x%"PRIx64 +vhost_vdpa_get_iova_range(void *dev, uint64_t first, uint64_t last) "dev: %p first: 0x%"PRIx64" last: 0x%"PRIx64 # virtio.c virtqueue_alloc_element(void *elem, size_t sz, unsigned in_num, unsigned out_num) "elem %p size %zd in_num %u out_num %u" -- 2.27.0
