diff options
| -rw-r--r-- | hw/block/virtio-blk.c | 2 | ||||
| -rw-r--r-- | hw/char/virtio-serial-bus.c | 2 | ||||
| -rw-r--r-- | hw/scsi/virtio-scsi.c | 3 | ||||
| -rw-r--r-- | hw/virtio/virtio.c | 887 | ||||
| -rw-r--r-- | include/hw/virtio/virtio.h | 10 |
5 files changed, 829 insertions, 75 deletions
diff --git a/hw/block/virtio-blk.c b/hw/block/virtio-blk.c index ba846fe9dc..7dbdeaaab9 100644 --- a/hw/block/virtio-blk.c +++ b/hw/block/virtio-blk.c @@ -1052,7 +1052,7 @@ static void virtio_blk_save_device(VirtIODevice *vdev, QEMUFile *f) qemu_put_be32(f, virtio_get_queue_index(req->vq)); } - qemu_put_virtqueue_element(f, &req->elem); + qemu_put_virtqueue_element(vdev, f, &req->elem); req = req->next; } qemu_put_sbyte(f, 0); diff --git a/hw/char/virtio-serial-bus.c b/hw/char/virtio-serial-bus.c index 4e0ed829ae..33259042a9 100644 --- a/hw/char/virtio-serial-bus.c +++ b/hw/char/virtio-serial-bus.c @@ -708,7 +708,7 @@ static void virtio_serial_save_device(VirtIODevice *vdev, QEMUFile *f) if (elem_popped) { qemu_put_be32s(f, &port->iov_idx); qemu_put_be64s(f, &port->iov_offset); - qemu_put_virtqueue_element(f, port->elem); + qemu_put_virtqueue_element(vdev, f, port->elem); } } } diff --git a/hw/scsi/virtio-scsi.c b/hw/scsi/virtio-scsi.c index ee52aa7d17..e8b2b64d09 100644 --- a/hw/scsi/virtio-scsi.c +++ b/hw/scsi/virtio-scsi.c @@ -190,11 +190,12 @@ static void virtio_scsi_save_request(QEMUFile *f, SCSIRequest *sreq) { VirtIOSCSIReq *req = sreq->hba_private; VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(req->dev); + VirtIODevice *vdev = VIRTIO_DEVICE(req->dev); uint32_t n = virtio_get_queue_index(req->vq) - 2; assert(n < vs->conf.num_queues); qemu_put_be32s(f, &n); - qemu_put_virtqueue_element(f, &req->elem); + qemu_put_virtqueue_element(vdev, f, &req->elem); } static void *virtio_scsi_load_request(QEMUFile *f, SCSIRequest *sreq) diff --git a/hw/virtio/virtio.c b/hw/virtio/virtio.c index 74cc10fad9..a694b4ab50 100644 --- a/hw/virtio/virtio.c +++ b/hw/virtio/virtio.c @@ -96,6 +96,7 @@ typedef struct VRingPackedDescEvent { struct VirtQueue { VRing vring; + VirtQueueElement *used_elems; /* Next head to pop */ uint16_t last_avail_idx; @@ -160,6 +161,7 @@ static void virtio_init_region_cache(VirtIODevice *vdev, int n) VRingMemoryRegionCaches *new = NULL; hwaddr addr, size; int64_t len; + bool packed; addr = vq->vring.desc; @@ -168,8 +170,10 @@ static void virtio_init_region_cache(VirtIODevice *vdev, int n) } new = g_new0(VRingMemoryRegionCaches, 1); size = virtio_queue_get_desc_size(vdev, n); + packed = virtio_vdev_has_feature(vq->vdev, VIRTIO_F_RING_PACKED) ? + true : false; len = address_space_cache_init(&new->desc, vdev->dma_as, - addr, size, false); + addr, size, packed); if (len < size) { virtio_error(vdev, "Cannot map desc"); goto err_desc; @@ -225,8 +229,8 @@ void virtio_queue_update_rings(VirtIODevice *vdev, int n) } /* Called within rcu_read_lock(). */ -static void vring_desc_read(VirtIODevice *vdev, VRingDesc *desc, - MemoryRegionCache *cache, int i) +static void vring_split_desc_read(VirtIODevice *vdev, VRingDesc *desc, + MemoryRegionCache *cache, int i) { address_space_read_cached(cache, i * sizeof(VRingDesc), desc, sizeof(VRingDesc)); @@ -236,6 +240,7 @@ static void vring_desc_read(VirtIODevice *vdev, VRingDesc *desc, virtio_tswap16s(vdev, &desc->next); } +/* Called within rcu_read_lock(). */ static VRingMemoryRegionCaches *vring_get_region_caches(struct VirtQueue *vq) { VRingMemoryRegionCaches *caches = atomic_rcu_read(&vq->vring.caches); @@ -370,6 +375,95 @@ int virtio_queue_ready(VirtQueue *vq) return vq->vring.avail != 0; } +static void vring_packed_desc_read_flags(VirtIODevice *vdev, + uint16_t *flags, + MemoryRegionCache *cache, + int i) +{ + address_space_read_cached(cache, + i * sizeof(VRingPackedDesc) + + offsetof(VRingPackedDesc, flags), + flags, sizeof(*flags)); + virtio_tswap16s(vdev, flags); +} + +static void vring_packed_desc_read(VirtIODevice *vdev, + VRingPackedDesc *desc, + MemoryRegionCache *cache, + int i, bool strict_order) +{ + hwaddr off = i * sizeof(VRingPackedDesc); + + vring_packed_desc_read_flags(vdev, &desc->flags, cache, i); + + if (strict_order) { + /* Make sure flags is read before the rest fields. */ + smp_rmb(); + } + + address_space_read_cached(cache, off + offsetof(VRingPackedDesc, addr), + &desc->addr, sizeof(desc->addr)); + address_space_read_cached(cache, off + offsetof(VRingPackedDesc, id), + &desc->id, sizeof(desc->id)); + address_space_read_cached(cache, off + offsetof(VRingPackedDesc, len), + &desc->len, sizeof(desc->len)); + virtio_tswap64s(vdev, &desc->addr); + virtio_tswap16s(vdev, &desc->id); + virtio_tswap32s(vdev, &desc->len); +} + +static void vring_packed_desc_write_data(VirtIODevice *vdev, + VRingPackedDesc *desc, + MemoryRegionCache *cache, + int i) +{ + hwaddr off_id = i * sizeof(VRingPackedDesc) + + offsetof(VRingPackedDesc, id); + hwaddr off_len = i * sizeof(VRingPackedDesc) + + offsetof(VRingPackedDesc, len); + + virtio_tswap32s(vdev, &desc->len); + virtio_tswap16s(vdev, &desc->id); + address_space_write_cached(cache, off_id, &desc->id, sizeof(desc->id)); + address_space_cache_invalidate(cache, off_id, sizeof(desc->id)); + address_space_write_cached(cache, off_len, &desc->len, sizeof(desc->len)); + address_space_cache_invalidate(cache, off_len, sizeof(desc->len)); +} + +static void vring_packed_desc_write_flags(VirtIODevice *vdev, + VRingPackedDesc *desc, + MemoryRegionCache *cache, + int i) +{ + hwaddr off = i * sizeof(VRingPackedDesc) + offsetof(VRingPackedDesc, flags); + + virtio_tswap16s(vdev, &desc->flags); + address_space_write_cached(cache, off, &desc->flags, sizeof(desc->flags)); + address_space_cache_invalidate(cache, off, sizeof(desc->flags)); +} + +static void vring_packed_desc_write(VirtIODevice *vdev, + VRingPackedDesc *desc, + MemoryRegionCache *cache, + int i, bool strict_order) +{ + vring_packed_desc_write_data(vdev, desc, cache, i); + if (strict_order) { + /* Make sure data is wrote before flags. */ + smp_wmb(); + } + vring_packed_desc_write_flags(vdev, desc, cache, i); +} + +static inline bool is_desc_avail(uint16_t flags, bool wrap_counter) +{ + bool avail, used; + + avail = !!(flags & (1 << VRING_PACKED_DESC_F_AVAIL)); + used = !!(flags & (1 << VRING_PACKED_DESC_F_USED)); + return (avail != used) && (avail == wrap_counter); +} + /* Fetch avail_idx from VQ memory only when we really need to know if * guest has added some buffers. * Called within rcu_read_lock(). */ @@ -390,7 +484,7 @@ static int virtio_queue_empty_rcu(VirtQueue *vq) return vring_avail_idx(vq) == vq->last_avail_idx; } -int virtio_queue_empty(VirtQueue *vq) +static int virtio_queue_split_empty(VirtQueue *vq) { bool empty; @@ -412,6 +506,41 @@ int virtio_queue_empty(VirtQueue *vq) return empty; } +static int virtio_queue_packed_empty_rcu(VirtQueue *vq) +{ + struct VRingPackedDesc desc; + VRingMemoryRegionCaches *cache; + + if (unlikely(!vq->vring.desc)) { + return 1; + } + + cache = vring_get_region_caches(vq); + vring_packed_desc_read_flags(vq->vdev, &desc.flags, &cache->desc, + vq->last_avail_idx); + + return !is_desc_avail(desc.flags, vq->last_avail_wrap_counter); +} + +static int virtio_queue_packed_empty(VirtQueue *vq) +{ + bool empty; + + rcu_read_lock(); + empty = virtio_queue_packed_empty_rcu(vq); + rcu_read_unlock(); + return empty; +} + +int virtio_queue_empty(VirtQueue *vq) +{ + if (virtio_vdev_has_feature(vq->vdev, VIRTIO_F_RING_PACKED)) { + return virtio_queue_packed_empty(vq); + } else { + return virtio_queue_split_empty(vq); + } +} + static void virtqueue_unmap_sg(VirtQueue *vq, const VirtQueueElement *elem, unsigned int len) { @@ -449,10 +578,25 @@ static void virtqueue_unmap_sg(VirtQueue *vq, const VirtQueueElement *elem, void virtqueue_detach_element(VirtQueue *vq, const VirtQueueElement *elem, unsigned int len) { - vq->inuse--; + vq->inuse -= elem->ndescs; virtqueue_unmap_sg(vq, elem, len); } +static void virtqueue_split_rewind(VirtQueue *vq, unsigned int num) +{ + vq->last_avail_idx -= num; +} + +static void virtqueue_packed_rewind(VirtQueue *vq, unsigned int num) +{ + if (vq->last_avail_idx < num) { + vq->last_avail_idx = vq->vring.num + vq->last_avail_idx - num; + vq->last_avail_wrap_counter ^= 1; + } else { + vq->last_avail_idx -= num; + } +} + /* virtqueue_unpop: * @vq: The #VirtQueue * @elem: The #VirtQueueElement @@ -464,7 +608,13 @@ void virtqueue_detach_element(VirtQueue *vq, const VirtQueueElement *elem, void virtqueue_unpop(VirtQueue *vq, const VirtQueueElement *elem, unsigned int len) { - vq->last_avail_idx--; + + if (virtio_vdev_has_feature(vq->vdev, VIRTIO_F_RING_PACKED)) { + virtqueue_packed_rewind(vq, 1); + } else { + virtqueue_split_rewind(vq, 1); + } + virtqueue_detach_element(vq, elem, len); } @@ -485,25 +635,21 @@ bool virtqueue_rewind(VirtQueue *vq, unsigned int num) if (num > vq->inuse) { return false; } - vq->last_avail_idx -= num; + vq->inuse -= num; + if (virtio_vdev_has_feature(vq->vdev, VIRTIO_F_RING_PACKED)) { + virtqueue_packed_rewind(vq, num); + } else { + virtqueue_split_rewind(vq, num); + } return true; } -/* Called within rcu_read_lock(). */ -void virtqueue_fill(VirtQueue *vq, const VirtQueueElement *elem, +static void virtqueue_split_fill(VirtQueue *vq, const VirtQueueElement *elem, unsigned int len, unsigned int idx) { VRingUsedElem uelem; - trace_virtqueue_fill(vq, elem, len, idx); - - virtqueue_unmap_sg(vq, elem, len); - - if (unlikely(vq->vdev->broken)) { - return; - } - if (unlikely(!vq->vring.used)) { return; } @@ -515,16 +661,72 @@ void virtqueue_fill(VirtQueue *vq, const VirtQueueElement *elem, vring_used_write(vq, &uelem, idx); } +static void virtqueue_packed_fill(VirtQueue *vq, const VirtQueueElement *elem, + unsigned int len, unsigned int idx) +{ + vq->used_elems[idx].index = elem->index; + vq->used_elems[idx].len = len; + vq->used_elems[idx].ndescs = elem->ndescs; +} + +static void virtqueue_packed_fill_desc(VirtQueue *vq, + const VirtQueueElement *elem, + unsigned int idx, + bool strict_order) +{ + uint16_t head; + VRingMemoryRegionCaches *caches; + VRingPackedDesc desc = { + .id = elem->index, + .len = elem->len, + }; + bool wrap_counter = vq->used_wrap_counter; + + if (unlikely(!vq->vring.desc)) { + return; + } + + head = vq->used_idx + idx; + if (head >= vq->vring.num) { + head -= vq->vring.num; + wrap_counter ^= 1; + } + if (wrap_counter) { + desc.flags |= (1 << VRING_PACKED_DESC_F_AVAIL); + desc.flags |= (1 << VRING_PACKED_DESC_F_USED); + } else { + desc.flags &= ~(1 << VRING_PACKED_DESC_F_AVAIL); + desc.flags &= ~(1 << VRING_PACKED_DESC_F_USED); + } + + caches = vring_get_region_caches(vq); + vring_packed_desc_write(vq->vdev, &desc, &caches->desc, head, strict_order); +} + /* Called within rcu_read_lock(). */ -void virtqueue_flush(VirtQueue *vq, unsigned int count) +void virtqueue_fill(VirtQueue *vq, const VirtQueueElement *elem, + unsigned int len, unsigned int idx) { - uint16_t old, new; + trace_virtqueue_fill(vq, elem, len, idx); + + virtqueue_unmap_sg(vq, elem, len); if (unlikely(vq->vdev->broken)) { - vq->inuse -= count; return; } + if (virtio_vdev_has_feature(vq->vdev, VIRTIO_F_RING_PACKED)) { + virtqueue_packed_fill(vq, elem, len, idx); + } else { + virtqueue_split_fill(vq, elem, len, idx); + } +} + +/* Called within rcu_read_lock(). */ +static void virtqueue_split_flush(VirtQueue *vq, unsigned int count) +{ + uint16_t old, new; + if (unlikely(!vq->vring.used)) { return; } @@ -540,6 +742,43 @@ void virtqueue_flush(VirtQueue *vq, unsigned int count) vq->signalled_used_valid = false; } +static void virtqueue_packed_flush(VirtQueue *vq, unsigned int count) +{ + unsigned int i, ndescs = 0; + + if (unlikely(!vq->vring.desc)) { + return; + } + + for (i = 1; i < count; i++) { + virtqueue_packed_fill_desc(vq, &vq->used_elems[i], i, false); + ndescs += vq->used_elems[i].ndescs; + } + virtqueue_packed_fill_desc(vq, &vq->used_elems[0], 0, true); + ndescs += vq->used_elems[0].ndescs; + + vq->inuse -= ndescs; + vq->used_idx += ndescs; + if (vq->used_idx >= vq->vring.num) { + vq->used_idx -= vq->vring.num; + vq->used_wrap_counter ^= 1; + } +} + +void virtqueue_flush(VirtQueue *vq, unsigned int count) +{ + if (unlikely(vq->vdev->broken)) { + vq->inuse -= count; + return; + } + + if (virtio_vdev_has_feature(vq->vdev, VIRTIO_F_RING_PACKED)) { + virtqueue_packed_flush(vq, count); + } else { + virtqueue_split_flush(vq, count); + } +} + void virtqueue_push(VirtQueue *vq, const VirtQueueElement *elem, unsigned int len) { @@ -592,9 +831,9 @@ enum { VIRTQUEUE_READ_DESC_MORE = 1, /* more buffers in chain */ }; -static int virtqueue_read_next_desc(VirtIODevice *vdev, VRingDesc *desc, - MemoryRegionCache *desc_cache, unsigned int max, - unsigned int *next) +static int virtqueue_split_read_next_desc(VirtIODevice *vdev, VRingDesc *desc, + MemoryRegionCache *desc_cache, + unsigned int max, unsigned int *next) { /* If this descriptor says it doesn't chain, we're done. */ if (!(desc->flags & VRING_DESC_F_NEXT)) { @@ -611,13 +850,13 @@ static int virtqueue_read_next_desc(VirtIODevice *vdev, VRingDesc *desc, return VIRTQUEUE_READ_DESC_ERROR; } - vring_desc_read(vdev, desc, desc_cache, *next); + vring_split_desc_read(vdev, desc, desc_cache, *next); return VIRTQUEUE_READ_DESC_MORE; } -void virtqueue_get_avail_bytes(VirtQueue *vq, unsigned int *in_bytes, - unsigned int *out_bytes, - unsigned max_in_bytes, unsigned max_out_bytes) +static void virtqueue_split_get_avail_bytes(VirtQueue *vq, + unsigned int *in_bytes, unsigned int *out_bytes, + unsigned max_in_bytes, unsigned max_out_bytes) { VirtIODevice *vdev = vq->vdev; unsigned int max, idx; @@ -627,27 +866,12 @@ void virtqueue_get_avail_bytes(VirtQueue *vq, unsigned int *in_bytes, int64_t len = 0; int rc; - if (unlikely(!vq->vring.desc)) { - if (in_bytes) { - *in_bytes = 0; - } - if (out_bytes) { - *out_bytes = 0; - } - return; - } - rcu_read_lock(); idx = vq->last_avail_idx; total_bufs = in_total = out_total = 0; max = vq->vring.num; caches = vring_get_region_caches(vq); - if (caches->desc.len < max * sizeof(VRingDesc)) { - virtio_error(vdev, "Cannot map descriptor ring"); - goto err; - } - while ((rc = virtqueue_num_heads(vq, idx)) > 0) { MemoryRegionCache *desc_cache = &caches->desc; unsigned int num_bufs; @@ -660,7 +884,7 @@ void virtqueue_get_avail_bytes(VirtQueue *vq, unsigned int *in_bytes, goto err; } - vring_desc_read(vdev, &desc, desc_cache, i); + vring_split_desc_read(vdev, &desc, desc_cache, i); if (desc.flags & VRING_DESC_F_INDIRECT) { if (!desc.len || (desc.len % sizeof(VRingDesc))) { @@ -686,7 +910,7 @@ void virtqueue_get_avail_bytes(VirtQueue *vq, unsigned int *in_bytes, max = desc.len / sizeof(VRingDesc); num_bufs = i = 0; - vring_desc_read(vdev, &desc, desc_cache, i); + vring_split_desc_read(vdev, &desc, desc_cache, i); } do { @@ -705,7 +929,7 @@ void virtqueue_get_avail_bytes(VirtQueue *vq, unsigned int *in_bytes, goto done; } - rc = virtqueue_read_next_desc(vdev, &desc, desc_cache, max, &i); + rc = virtqueue_split_read_next_desc(vdev, &desc, desc_cache, max, &i); } while (rc == VIRTQUEUE_READ_DESC_MORE); if (rc == VIRTQUEUE_READ_DESC_ERROR) { @@ -740,6 +964,186 @@ err: goto done; } +static int virtqueue_packed_read_next_desc(VirtQueue *vq, + VRingPackedDesc *desc, + MemoryRegionCache + *desc_cache, + unsigned int max, + unsigned int *next, + bool indirect) +{ + /* If this descriptor says it doesn't chain, we're done. */ + if (!indirect && !(desc->flags & VRING_DESC_F_NEXT)) { + return VIRTQUEUE_READ_DESC_DONE; + } + + ++*next; + if (*next == max) { + if (indirect) { + return VIRTQUEUE_READ_DESC_DONE; + } else { + (*next) -= vq->vring.num; + } + } + + vring_packed_desc_read(vq->vdev, desc, desc_cache, *next, false); + return VIRTQUEUE_READ_DESC_MORE; +} + +static void virtqueue_packed_get_avail_bytes(VirtQueue *vq, + unsigned int *in_bytes, + unsigned int *out_bytes, + unsigned max_in_bytes, + unsigned max_out_bytes) +{ + VirtIODevice *vdev = vq->vdev; + unsigned int max, idx; + unsigned int total_bufs, in_total, out_total; + MemoryRegionCache *desc_cache; + VRingMemoryRegionCaches *caches; + MemoryRegionCache indirect_desc_cache = MEMORY_REGION_CACHE_INVALID; + int64_t len = 0; + VRingPackedDesc desc; + bool wrap_counter; + + rcu_read_lock(); + idx = vq->last_avail_idx; + wrap_counter = vq->last_avail_wrap_counter; + total_bufs = in_total = out_total = 0; + + max = vq->vring.num; + caches = vring_get_region_caches(vq); + + for (;;) { + unsigned int num_bufs = total_bufs; + unsigned int i = idx; + int rc; + + desc_cache = &caches->desc; + vring_packed_desc_read(vdev, &desc, desc_cache, idx, true); + if (!is_desc_avail(desc.flags, wrap_counter)) { + break; + } + + if (desc.flags & VRING_DESC_F_INDIRECT) { + if (desc.len % sizeof(VRingPackedDesc)) { + virtio_error(vdev, "Invalid size for indirect buffer table"); + goto err; + } + + /* If we've got too many, that implies a descriptor loop. */ + if (num_bufs >= max) { + virtio_error(vdev, "Looped descriptor"); + goto err; + } + + /* loop over the indirect descriptor table */ + len = address_space_cache_init(&indirect_desc_cache, + vdev->dma_as, + desc.addr, desc.len, false); + desc_cache = &indirect_desc_cache; + if (len < desc.len) { + virtio_error(vdev, "Cannot map indirect buffer"); + goto err; + } + + max = desc.len / sizeof(VRingPackedDesc); + num_bufs = i = 0; + vring_packed_desc_read(vdev, &desc, desc_cache, i, false); + } + + do { + /* If we've got too many, that implies a descriptor loop. */ + if (++num_bufs > max) { + virtio_error(vdev, "Looped descriptor"); + goto err; + } + + if (desc.flags & VRING_DESC_F_WRITE) { + in_total += desc.len; + } else { + out_total += desc.len; + } + if (in_total >= max_in_bytes && out_total >= max_out_bytes) { + goto done; + } + + rc = virtqueue_packed_read_next_desc(vq, &desc, desc_cache, max, + &i, desc_cache == + &indirect_desc_cache); + } while (rc == VIRTQUEUE_READ_DESC_MORE); + + if (desc_cache == &indirect_desc_cache) { + address_space_cache_destroy(&indirect_desc_cache); + total_bufs++; + idx++; + } else { + idx += num_bufs - total_bufs; + total_bufs = num_bufs; + } + + if (idx >= vq->vring.num) { + idx -= vq->vring.num; + wrap_counter ^= 1; + } + } + + /* Record the index and wrap counter for a kick we want */ + vq->shadow_avail_idx = idx; + vq->shadow_avail_wrap_counter = wrap_counter; +done: + address_space_cache_destroy(&indirect_desc_cache); + if (in_bytes) { + *in_bytes = in_total; + } + if (out_bytes) { + *out_bytes = out_total; + } + rcu_read_unlock(); + return; + +err: + in_total = out_total = 0; + goto done; +} + +void virtqueue_get_avail_bytes(VirtQueue *vq, unsigned int *in_bytes, + unsigned int *out_bytes, + unsigned max_in_bytes, unsigned max_out_bytes) +{ + uint16_t desc_size; + VRingMemoryRegionCaches *caches; + + if (unlikely(!vq->vring.desc)) { + goto err; + } + + caches = vring_get_region_caches(vq); + desc_size = virtio_vdev_has_feature(vq->vdev, VIRTIO_F_RING_PACKED) ? + sizeof(VRingPackedDesc) : sizeof(VRingDesc); + if (caches->desc.len < vq->vring.num * desc_size) { + virtio_error(vq->vdev, "Cannot map descriptor ring"); + goto err; + } + + if (virtio_vdev_has_feature(vq->vdev, VIRTIO_F_RING_PACKED)) { + virtqueue_packed_get_avail_bytes(vq, in_bytes, out_bytes, + max_in_bytes, max_out_bytes); + } else { + virtqueue_split_get_avail_bytes(vq, in_bytes, out_bytes, + max_in_bytes, max_out_bytes); + } + + return; +err: + if (in_bytes) { + *in_bytes = 0; + } + if (out_bytes) { + *out_bytes = 0; + } +} + int virtqueue_avail_bytes(VirtQueue *vq, unsigned int in_bytes, unsigned int out_bytes) { @@ -864,7 +1268,7 @@ static void *virtqueue_alloc_element(size_t sz, unsigned out_num, unsigned in_nu return elem; } -void *virtqueue_pop(VirtQueue *vq, size_t sz) +static void *virtqueue_split_pop(VirtQueue *vq, size_t sz) { unsigned int i, head, max; VRingMemoryRegionCaches *caches; @@ -879,9 +1283,6 @@ void *virtqueue_pop(VirtQueue *vq, size_t sz) VRingDesc desc; int rc; - if (unlikely(vdev->broken)) { - return NULL; - } rcu_read_lock(); if (virtio_queue_empty_rcu(vq)) { goto done; @@ -917,7 +1318,7 @@ void *virtqueue_pop(VirtQueue *vq, size_t sz) } desc_cache = &caches->desc; - vring_desc_read(vdev, &desc, desc_cache, i); + vring_split_desc_read(vdev, &desc, desc_cache, i); if (desc.flags & VRING_DESC_F_INDIRECT) { if (!desc.len || (desc.len % sizeof(VRingDesc))) { virtio_error(vdev, "Invalid size for indirect buffer table"); @@ -935,7 +1336,7 @@ void *virtqueue_pop(VirtQueue *vq, size_t sz) max = desc.len / sizeof(VRingDesc); i = 0; - vring_desc_read(vdev, &desc, desc_cache, i); + vring_split_desc_read(vdev, &desc, desc_cache, i); } /* Collect all the descriptors */ @@ -966,7 +1367,7 @@ void *virtqueue_pop(VirtQueue *vq, size_t sz) goto err_undo_map; } - rc = virtqueue_read_next_desc(vdev, &desc, desc_cache, max, &i); + rc = virtqueue_split_read_next_desc(vdev, &desc, desc_cache, max, &i); } while (rc == VIRTQUEUE_READ_DESC_MORE); if (rc == VIRTQUEUE_READ_DESC_ERROR) { @@ -976,6 +1377,7 @@ void *virtqueue_pop(VirtQueue *vq, size_t sz) /* Now copy what we have collected and mapped */ elem = virtqueue_alloc_element(sz, out_num, in_num); elem->index = head; + elem->ndescs = 1; for (i = 0; i < out_num; i++) { elem->out_addr[i] = addr[i]; elem->out_sg[i] = iov[i]; @@ -999,23 +1401,204 @@ err_undo_map: goto done; } -/* virtqueue_drop_all: - * @vq: The #VirtQueue - * Drops all queued buffers and indicates them to the guest - * as if they are done. Useful when buffers can not be - * processed but must be returned to the guest. - */ -unsigned int virtqueue_drop_all(VirtQueue *vq) +static void *virtqueue_packed_pop(VirtQueue *vq, size_t sz) { + unsigned int i, max; + VRingMemoryRegionCaches *caches; + MemoryRegionCache indirect_desc_cache = MEMORY_REGION_CACHE_INVALID; + MemoryRegionCache *desc_cache; + int64_t len; + VirtIODevice *vdev = vq->vdev; + VirtQueueElement *elem = NULL; + unsigned out_num, in_num, elem_entries; + hwaddr addr[VIRTQUEUE_MAX_SIZE]; + struct iovec iov[VIRTQUEUE_MAX_SIZE]; + VRingPackedDesc desc; + uint16_t id; + int rc; + + rcu_read_lock(); + if (virtio_queue_packed_empty_rcu(vq)) { + goto done; + } + + /* When we start there are none of either input nor output. */ + out_num = in_num = elem_entries = 0; + + max = vq->vring.num; + + if (vq->inuse >= vq->vring.num) { + virtio_error(vdev, "Virtqueue size exceeded"); + goto done; + } + + i = vq->last_avail_idx; + + caches = vring_get_region_caches(vq); + if (caches->desc.len < max * sizeof(VRingDesc)) { + virtio_error(vdev, "Cannot map descriptor ring"); + goto done; + } + + desc_cache = &caches->desc; + vring_packed_desc_read(vdev, &desc, desc_cache, i, true); + id = desc.id; + if (desc.flags & VRING_DESC_F_INDIRECT) { + if (desc.len % sizeof(VRingPackedDesc)) { + virtio_error(vdev, "Invalid size for indirect buffer table"); + goto done; + } + + /* loop over the indirect descriptor table */ + len = address_space_cache_init(&indirect_desc_cache, vdev->dma_as, + desc.addr, desc.len, false); + desc_cache = &indirect_desc_cache; + if (len < desc.len) { + virtio_error(vdev, "Cannot map indirect buffer"); + goto done; + } + + max = desc.len / sizeof(VRingPackedDesc); + i = 0; + vring_packed_desc_read(vdev, &desc, desc_cache, i, false); + } + + /* Collect all the descriptors */ + do { + bool map_ok; + + if (desc.flags & VRING_DESC_F_WRITE) { + map_ok = virtqueue_map_desc(vdev, &in_num, addr + out_num, + iov + out_num, + VIRTQUEUE_MAX_SIZE - out_num, true, + desc.addr, desc.len); + } else { + if (in_num) { + virtio_error(vdev, "Incorrect order for descriptors"); + goto err_undo_map; + } + map_ok = virtqueue_map_desc(vdev, &out_num, addr, iov, + VIRTQUEUE_MAX_SIZE, false, + desc.addr, desc.len); + } + if (!map_ok) { + goto err_undo_map; + } + + /* If we've got too many, that implies a descriptor loop. */ + if (++elem_entries > max) { + virtio_error(vdev, "Looped descriptor"); + goto err_undo_map; + } + + rc = virtqueue_packed_read_next_desc(vq, &desc, desc_cache, max, &i, + desc_cache == + &indirect_desc_cache); + } while (rc == VIRTQUEUE_READ_DESC_MORE); + + /* Now copy what we have collected and mapped */ + elem = virtqueue_alloc_element(sz, out_num, in_num); + for (i = 0; i < out_num; i++) { + elem->out_addr[i] = addr[i]; + elem->out_sg[i] = iov[i]; + } + for (i = 0; i < in_num; i++) { + elem->in_addr[i] = addr[out_num + i]; + elem->in_sg[i] = iov[out_num + i]; + } + + elem->index = id; + elem->ndescs = (desc_cache == &indirect_desc_cache) ? 1 : elem_entries; + vq->last_avail_idx += elem->ndescs; + vq->inuse += elem->ndescs; + + if (vq->last_avail_idx >= vq->vring.num) { + vq->last_avail_idx -= vq->vring.num; + vq->last_avail_wrap_counter ^= 1; + } + + vq->shadow_avail_idx = vq->last_avail_idx; + vq->shadow_avail_wrap_counter = vq->last_avail_wrap_counter; + + trace_virtqueue_pop(vq, elem, elem->in_num, elem->out_num); +done: + address_space_cache_destroy(&indirect_desc_cache); + rcu_read_unlock(); + + return elem; + +err_undo_map: + virtqueue_undo_map_desc(out_num, in_num, iov); + goto done; +} + +void *virtqueue_pop(VirtQueue *vq, size_t sz) +{ + if (unlikely(vq->vdev->broken)) { + return NULL; + } + + if (virtio_vdev_has_feature(vq->vdev, VIRTIO_F_RING_PACKED)) { + return virtqueue_packed_pop(vq, sz); + } else { + return virtqueue_split_pop(vq, sz); + } +} + +static unsigned int virtqueue_packed_drop_all(VirtQueue *vq) +{ + VRingMemoryRegionCaches *caches; + MemoryRegionCache *desc_cache; unsigned int dropped = 0; VirtQueueElement elem = {}; VirtIODevice *vdev = vq->vdev; - bool fEventIdx = virtio_vdev_has_feature(vdev, VIRTIO_RING_F_EVENT_IDX); + VRingPackedDesc desc; - if (unlikely(vdev->broken)) { - return 0; + caches = vring_get_region_caches(vq); + desc_cache = &caches->desc; + + virtio_queue_set_notification(vq, 0); + + while (vq->inuse < vq->vring.num) { + unsigned int idx = vq->last_avail_idx; + /* + * works similar to virtqueue_pop but does not map buffers + * and does not allocate any memory. + */ + vring_packed_desc_read(vdev, &desc, desc_cache, + vq->last_avail_idx , true); + if (!is_desc_avail(desc.flags, vq->last_avail_wrap_counter)) { + break; + } + elem.index = desc.id; + elem.ndescs = 1; + while (virtqueue_packed_read_next_desc(vq, &desc, desc_cache, + vq->vring.num, &idx, false)) { + ++elem.ndescs; + } + /* + * immediately push the element, nothing to unmap + * as both in_num and out_num are set to 0. + */ + virtqueue_push(vq, &elem, 0); + dropped++; + vq->last_avail_idx += elem.ndescs; + if (vq->last_avail_idx >= vq->vring.num) { + vq->last_avail_idx -= vq->vring.num; + vq->last_avail_wrap_counter ^= 1; + } } + return dropped; +} + +static unsigned int virtqueue_split_drop_all(VirtQueue *vq) +{ + unsigned int dropped = 0; + VirtQueueElement elem = {}; + VirtIODevice *vdev = vq->vdev; + bool fEventIdx = virtio_vdev_has_feature(vdev, VIRTIO_RING_F_EVENT_IDX); + while (!virtio_queue_empty(vq) && vq->inuse < vq->vring.num) { /* works similar to virtqueue_pop but does not map buffers * and does not allocate any memory */ @@ -1037,6 +1620,27 @@ unsigned int virtqueue_drop_all(VirtQueue *vq) return dropped; } +/* virtqueue_drop_all: + * @vq: The #VirtQueue + * Drops all queued buffers and indicates them to the guest + * as if they are done. Useful when buffers can not be + * processed but must be returned to the guest. + */ +unsigned int virtqueue_drop_all(VirtQueue *vq) +{ + struct VirtIODevice *vdev = vq->vdev; + + if (unlikely(vdev->broken)) { + return 0; + } + + if (virtio_vdev_has_feature(vdev, VIRTIO_F_RING_PACKED)) { + return virtqueue_packed_drop_all(vq); + } else { + return virtqueue_split_drop_all(vq); + } +} + /* Reading and writing a structure directly to QEMUFile is *awful*, but * it is what QEMU has always done by mistake. We can change it sooner * or later by bumping the version number of the affected vm states. @@ -1093,11 +1697,16 @@ void *qemu_get_virtqueue_element(VirtIODevice *vdev, QEMUFile *f, size_t sz) elem->out_sg[i].iov_len = data.out_sg[i].iov_len; } + if (virtio_host_has_feature(vdev, VIRTIO_F_RING_PACKED)) { + qemu_get_be32s(f, &elem->ndescs); + } + virtqueue_map(vdev, elem); return elem; } -void qemu_put_virtqueue_element(QEMUFile *f, VirtQueueElement *elem) +void qemu_put_virtqueue_element(VirtIODevice *vdev, QEMUFile *f, + VirtQueueElement *elem) { VirtQueueElementOld data; int i; @@ -1125,6 +1734,11 @@ void qemu_put_virtqueue_element(QEMUFile *f, VirtQueueElement *elem) /* Do not save iov_base as above. */ data.out_sg[i].iov_len = elem->out_sg[i].iov_len; } + + if (virtio_host_has_feature(vdev, VIRTIO_F_RING_PACKED)) { + qemu_put_be32s(f, &elem->ndescs); + } + qemu_put_buffer(f, (uint8_t *)&data, sizeof(VirtQueueElementOld)); } @@ -1249,6 +1863,9 @@ void virtio_reset(void *opaque) vdev->vq[i].last_avail_idx = 0; vdev->vq[i].shadow_avail_idx = 0; vdev->vq[i].used_idx = 0; + vdev->vq[i].last_avail_wrap_counter = true; + vdev->vq[i].shadow_avail_wrap_counter = true; + vdev->vq[i].used_wrap_counter = true; virtio_queue_set_vector(vdev, i, VIRTIO_NO_VECTOR); vdev->vq[i].signalled_used = 0; vdev->vq[i].signalled_used_valid = false; @@ -1639,6 +2256,8 @@ VirtQueue *virtio_add_queue(VirtIODevice *vdev, int queue_size, vdev->vq[i].vring.align = VIRTIO_PCI_VRING_ALIGN; vdev->vq[i].handle_output = handle_output; vdev->vq[i].handle_aio_output = NULL; + vdev->vq[i].used_elems = g_malloc0(sizeof(VirtQueueElement) * + queue_size); return &vdev->vq[i]; } @@ -1653,6 +2272,7 @@ void virtio_del_queue(VirtIODevice *vdev, int n) vdev->vq[n].vring.num_default = 0; vdev->vq[n].handle_output = NULL; vdev->vq[n].handle_aio_output = NULL; + g_free(vdev->vq[n].used_elems); } static void virtio_set_isr(VirtIODevice *vdev, int value) @@ -1780,6 +2400,13 @@ static bool virtio_virtqueue_needed(void *opaque) return virtio_host_has_feature(vdev, VIRTIO_F_VERSION_1); } +static bool virtio_packed_virtqueue_needed(void *opaque) +{ + VirtIODevice *vdev = opaque; + + return virtio_host_has_feature(vdev, VIRTIO_F_RING_PACKED); +} + static bool virtio_ringsize_needed(void *opaque) { VirtIODevice *vdev = opaque; @@ -1828,6 +2455,20 @@ static const VMStateDescription vmstate_virtqueue = { } }; +static const VMStateDescription vmstate_packed_virtqueue = { + .name = "packed_virtqueue_state", + .version_id = 1, + .minimum_version_id = 1, + .fields = (VMStateField[]) { + VMSTATE_UINT16(last_avail_idx, struct VirtQueue), + VMSTATE_BOOL(last_avail_wrap_counter, struct VirtQueue), + VMSTATE_UINT16(used_idx, struct VirtQueue), + VMSTATE_BOOL(used_wrap_counter, struct VirtQueue), + VMSTATE_UINT32(inuse, struct VirtQueue), + VMSTATE_END_OF_LIST() + } +}; + static const VMStateDescription vmstate_virtio_virtqueues = { .name = "virtio/virtqueues", .version_id = 1, @@ -1840,6 +2481,18 @@ static const VMStateDescription vmstate_virtio_virtqueues = { } }; +static const VMStateDescription vmstate_virtio_packed_virtqueues = { + .name = "virtio/packed_virtqueues", + .version_id = 1, + .minimum_version_id = 1, + .needed = &virtio_packed_virtqueue_needed, + .fields = (VMStateField[]) { + VMSTATE_STRUCT_VARRAY_POINTER_KNOWN(vq, struct VirtIODevice, + VIRTIO_QUEUE_MAX, 0, vmstate_packed_virtqueue, VirtQueue), + VMSTATE_END_OF_LIST() + } +}; + static const VMStateDescription vmstate_ringsize = { .name = "ringsize_state", .version_id = 1, @@ -1972,6 +2625,7 @@ static const VMStateDescription vmstate_virtio = { &vmstate_virtio_broken, &vmstate_virtio_extra_state, &vmstate_virtio_started, + &vmstate_virtio_packed_virtqueues, NULL } }; @@ -2271,6 +2925,13 @@ int virtio_load(VirtIODevice *vdev, QEMUFile *f, int version_id) virtio_queue_update_rings(vdev, i); } + if (virtio_vdev_has_feature(vdev, VIRTIO_F_RING_PACKED)) { + vdev->vq[i].shadow_avail_idx = vdev->vq[i].last_avail_idx; + vdev->vq[i].shadow_avail_wrap_counter = + vdev->vq[i].last_avail_wrap_counter; + continue; + } + nheads = vring_avail_idx(&vdev->vq[i]) - vdev->vq[i].last_avail_idx; /* Check it isn't doing strange things with descriptor numbers. */ if (nheads > vdev->vq[i].vring.num) { @@ -2414,6 +3075,10 @@ hwaddr virtio_queue_get_avail_size(VirtIODevice *vdev, int n) { int s; + if (virtio_vdev_has_feature(vdev, VIRTIO_F_RING_PACKED)) { + return sizeof(struct VRingPackedDescEvent); + } + s = virtio_vdev_has_feature(vdev, VIRTIO_RING_F_EVENT_IDX) ? 2 : 0; return offsetof(VRingAvail, ring) + sizeof(uint16_t) * vdev->vq[n].vring.num + s; @@ -2423,23 +3088,83 @@ hwaddr virtio_queue_get_used_size(VirtIODevice *vdev, int n) { int s; + if (virtio_vdev_has_feature(vdev, VIRTIO_F_RING_PACKED)) { + return sizeof(struct VRingPackedDescEvent); + } + s = virtio_vdev_has_feature(vdev, VIRTIO_RING_F_EVENT_IDX) ? 2 : 0; return offsetof(VRingUsed, ring) + sizeof(VRingUsedElem) * vdev->vq[n].vring.num + s; } -uint16_t virtio_queue_get_last_avail_idx(VirtIODevice *vdev, int n) +static unsigned int virtio_queue_packed_get_last_avail_idx(VirtIODevice *vdev, + int n) +{ + unsigned int avail, used; + + avail = vdev->vq[n].last_avail_idx; + avail |= ((uint16_t)vdev->vq[n].last_avail_wrap_counter) << 15; + + used = vdev->vq[n].used_idx; + used |= ((uint16_t)vdev->vq[n].used_wrap_counter) << 15; + + return avail | used << 16; +} + +static uint16_t virtio_queue_split_get_last_avail_idx(VirtIODevice *vdev, + int n) { return vdev->vq[n].last_avail_idx; } -void virtio_queue_set_last_avail_idx(VirtIODevice *vdev, int n, uint16_t idx) +unsigned int virtio_queue_get_last_avail_idx(VirtIODevice *vdev, int n) { - vdev->vq[n].last_avail_idx = idx; - vdev->vq[n].shadow_avail_idx = idx; + if (virtio_vdev_has_feature(vdev, VIRTIO_F_RING_PACKED)) { + return virtio_queue_packed_get_last_avail_idx(vdev, n); + } else { + return virtio_queue_split_get_last_avail_idx(vdev, n); + } } -void virtio_queue_restore_last_avail_idx(VirtIODevice *vdev, int n) +static void virtio_queue_packed_set_last_avail_idx(VirtIODevice *vdev, + int n, unsigned int idx) +{ + struct VirtQueue *vq = &vdev->vq[n]; + + vq->last_avail_idx = vq->shadow_avail_idx = idx & 0x7fff; + vq->last_avail_wrap_counter = + vq->shadow_avail_wrap_counter = !!(idx & 0x8000); + idx >>= 16; + vq->used_idx = idx & 0x7ffff; + vq->used_wrap_counter = !!(idx & 0x8000); +} + +static void virtio_queue_split_set_last_avail_idx(VirtIODevice *vdev, + int n, unsigned int idx) +{ + vdev->vq[n].last_avail_idx = idx; + vdev->vq[n].shadow_avail_idx = idx; +} + +void virtio_queue_set_last_avail_idx(VirtIODevice *vdev, int n, + unsigned int idx) +{ + if (virtio_vdev_has_feature(vdev, VIRTIO_F_RING_PACKED)) { + virtio_queue_packed_set_last_avail_idx(vdev, n, idx); + } else { + virtio_queue_split_set_last_avail_idx(vdev, n, idx); + } +} + +static void virtio_queue_packed_restore_last_avail_idx(VirtIODevice *vdev, + int n) +{ + /* We don't have a reference like avail idx in shared memory */ + return; +} + +static void virtio_queue_split_restore_last_avail_idx(VirtIODevice *vdev, + int n) { rcu_read_lock(); if (vdev->vq[n].vring.desc) { @@ -2449,7 +3174,22 @@ void virtio_queue_restore_last_avail_idx(VirtIODevice *vdev, int n) rcu_read_unlock(); } -void virtio_queue_update_used_idx(VirtIODevice *vdev, int n) +void virtio_queue_restore_last_avail_idx(VirtIODevice *vdev, int n) +{ + if (virtio_vdev_has_feature(vdev, VIRTIO_F_RING_PACKED)) { + virtio_queue_packed_restore_last_avail_idx(vdev, n); + } else { + virtio_queue_split_restore_last_avail_idx(vdev, n); + } +} + +static void virtio_queue_packed_update_used_idx(VirtIODevice *vdev, int n) +{ + /* used idx was updated through set_last_avail_idx() */ + return; +} + +static void virtio_split_packed_update_used_idx(VirtIODevice *vdev, int n) { rcu_read_lock(); if (vdev->vq[n].vring.desc) { @@ -2458,6 +3198,15 @@ void virtio_queue_update_used_idx(VirtIODevice *vdev, int n) rcu_read_unlock(); } +void virtio_queue_update_used_idx(VirtIODevice *vdev, int n) +{ + if (virtio_vdev_has_feature(vdev, VIRTIO_F_RING_PACKED)) { + return virtio_queue_packed_update_used_idx(vdev, n); + } else { + return virtio_split_packed_update_used_idx(vdev, n); + } +} + void virtio_queue_invalidate_signalled_used(VirtIODevice *vdev, int n) { vdev->vq[n].signalled_used_valid = false; diff --git a/include/hw/virtio/virtio.h b/include/hw/virtio/virtio.h index 48e8d04ff6..d123d5b181 100644 --- a/include/hw/virtio/virtio.h +++ b/include/hw/virtio/virtio.h @@ -59,6 +59,8 @@ typedef struct VirtQueue VirtQueue; typedef struct VirtQueueElement { unsigned int index; + unsigned int len; + unsigned int ndescs; unsigned int out_num; unsigned int in_num; hwaddr *in_addr; @@ -196,7 +198,8 @@ void virtqueue_map(VirtIODevice *vdev, VirtQueueElement *elem); void *virtqueue_pop(VirtQueue *vq, size_t sz); unsigned int virtqueue_drop_all(VirtQueue *vq); void *qemu_get_virtqueue_element(VirtIODevice *vdev, QEMUFile *f, size_t sz); -void qemu_put_virtqueue_element(QEMUFile *f, VirtQueueElement *elem); +void qemu_put_virtqueue_element(VirtIODevice *vdev, QEMUFile *f, + VirtQueueElement *elem); int virtqueue_avail_bytes(VirtQueue *vq, unsigned int in_bytes, unsigned int out_bytes); void virtqueue_get_avail_bytes(VirtQueue *vq, unsigned int *in_bytes, @@ -291,8 +294,9 @@ hwaddr virtio_queue_get_used_addr(VirtIODevice *vdev, int n); hwaddr virtio_queue_get_desc_size(VirtIODevice *vdev, int n); hwaddr virtio_queue_get_avail_size(VirtIODevice *vdev, int n); hwaddr virtio_queue_get_used_size(VirtIODevice *vdev, int n); -uint16_t virtio_queue_get_last_avail_idx(VirtIODevice *vdev, int n); -void virtio_queue_set_last_avail_idx(VirtIODevice *vdev, int n, uint16_t idx); +unsigned int virtio_queue_get_last_avail_idx(VirtIODevice *vdev, int n); +void virtio_queue_set_last_avail_idx(VirtIODevice *vdev, int n, + unsigned int idx); void virtio_queue_restore_last_avail_idx(VirtIODevice *vdev, int n); void virtio_queue_invalidate_signalled_used(VirtIODevice *vdev, int n); void virtio_queue_update_used_idx(VirtIODevice *vdev, int n); |