diff options
| -rw-r--r-- | hw/block/dataplane/virtio-blk.c | 29 | ||||
| -rw-r--r-- | hw/block/virtio-blk.c | 46 | ||||
| -rw-r--r-- | hw/virtio/dataplane/vring.c | 17 | ||||
| -rw-r--r-- | include/hw/virtio/dataplane/vring.h | 2 | ||||
| -rw-r--r-- | include/hw/virtio/virtio-blk.h | 6 |
5 files changed, 48 insertions, 52 deletions
diff --git a/hw/block/dataplane/virtio-blk.c b/hw/block/dataplane/virtio-blk.c index bed9f13793..227bb15efc 100644 --- a/hw/block/dataplane/virtio-blk.c +++ b/hw/block/dataplane/virtio-blk.c @@ -65,7 +65,7 @@ static void complete_request_vring(VirtIOBlockReq *req, unsigned char status) { stb_p(&req->in->status, status); - vring_push(&req->dev->dataplane->vring, req->elem, + vring_push(&req->dev->dataplane->vring, &req->elem, req->qiov.size + sizeof(*req->in)); notify_guest(req->dev->dataplane); } @@ -74,33 +74,32 @@ static void handle_notify(EventNotifier *e) { VirtIOBlockDataPlane *s = container_of(e, VirtIOBlockDataPlane, host_notifier); - - VirtQueueElement *elem; - VirtIOBlockReq *req; - int ret; - MultiReqBuffer mrb = { - .num_writes = 0, - }; + VirtIOBlock *vblk = VIRTIO_BLK(s->vdev); event_notifier_test_and_clear(&s->host_notifier); bdrv_io_plug(s->blk->conf.bs); for (;;) { + MultiReqBuffer mrb = { + .num_writes = 0, + }; + int ret; + /* Disable guest->host notifies to avoid unnecessary vmexits */ vring_disable_notification(s->vdev, &s->vring); for (;;) { - ret = vring_pop(s->vdev, &s->vring, &elem); + VirtIOBlockReq *req = virtio_blk_alloc_request(vblk); + + ret = vring_pop(s->vdev, &s->vring, &req->elem); if (ret < 0) { - assert(elem == NULL); + virtio_blk_free_request(req); break; /* no more requests */ } - trace_virtio_blk_data_plane_process_request(s, elem->out_num, - elem->in_num, elem->index); + trace_virtio_blk_data_plane_process_request(s, req->elem.out_num, + req->elem.in_num, + req->elem.index); - req = g_slice_new(VirtIOBlockReq); - req->dev = VIRTIO_BLK(s->vdev); - req->elem = elem; virtio_blk_handle_request(req, &mrb); } diff --git a/hw/block/virtio-blk.c b/hw/block/virtio-blk.c index b06a56d942..02cd6b059a 100644 --- a/hw/block/virtio-blk.c +++ b/hw/block/virtio-blk.c @@ -29,20 +29,18 @@ #include "hw/virtio/virtio-bus.h" #include "hw/virtio/virtio-access.h" -static VirtIOBlockReq *virtio_blk_alloc_request(VirtIOBlock *s) +VirtIOBlockReq *virtio_blk_alloc_request(VirtIOBlock *s) { VirtIOBlockReq *req = g_slice_new(VirtIOBlockReq); req->dev = s; req->qiov.size = 0; req->next = NULL; - req->elem = g_slice_new(VirtQueueElement); return req; } -static void virtio_blk_free_request(VirtIOBlockReq *req) +void virtio_blk_free_request(VirtIOBlockReq *req) { if (req) { - g_slice_free(VirtQueueElement, req->elem); g_slice_free(VirtIOBlockReq, req); } } @@ -56,7 +54,7 @@ static void virtio_blk_complete_request(VirtIOBlockReq *req, trace_virtio_blk_req_complete(req, status); stb_p(&req->in->status, status); - virtqueue_push(s->vq, req->elem, req->qiov.size + sizeof(*req->in)); + virtqueue_push(s->vq, &req->elem, req->qiov.size + sizeof(*req->in)); virtio_notify(vdev, s->vq); } @@ -121,7 +119,7 @@ static VirtIOBlockReq *virtio_blk_get_request(VirtIOBlock *s) { VirtIOBlockReq *req = virtio_blk_alloc_request(s); - if (!virtqueue_pop(s->vq, req->elem)) { + if (!virtqueue_pop(s->vq, &req->elem)) { virtio_blk_free_request(req); return NULL; } @@ -254,7 +252,7 @@ static void virtio_blk_handle_scsi(VirtIOBlockReq *req) { int status; - status = virtio_blk_handle_scsi_req(req->dev, req->elem); + status = virtio_blk_handle_scsi_req(req->dev, &req->elem); virtio_blk_req_complete(req, status); virtio_blk_free_request(req); } @@ -351,12 +349,12 @@ static void virtio_blk_handle_read(VirtIOBlockReq *req) void virtio_blk_handle_request(VirtIOBlockReq *req, MultiReqBuffer *mrb) { uint32_t type; - struct iovec *in_iov = req->elem->in_sg; - struct iovec *iov = req->elem->out_sg; - unsigned in_num = req->elem->in_num; - unsigned out_num = req->elem->out_num; + struct iovec *in_iov = req->elem.in_sg; + struct iovec *iov = req->elem.out_sg; + unsigned in_num = req->elem.in_num; + unsigned out_num = req->elem.out_num; - if (req->elem->out_num < 1 || req->elem->in_num < 1) { + if (req->elem.out_num < 1 || req->elem.in_num < 1) { error_report("virtio-blk missing headers"); exit(1); } @@ -393,19 +391,19 @@ void virtio_blk_handle_request(VirtIOBlockReq *req, MultiReqBuffer *mrb) * NB: per existing s/n string convention the string is * terminated by '\0' only when shorter than buffer. */ - strncpy(req->elem->in_sg[0].iov_base, + strncpy(req->elem.in_sg[0].iov_base, s->blk.serial ? s->blk.serial : "", - MIN(req->elem->in_sg[0].iov_len, VIRTIO_BLK_ID_BYTES)); + MIN(req->elem.in_sg[0].iov_len, VIRTIO_BLK_ID_BYTES)); virtio_blk_req_complete(req, VIRTIO_BLK_S_OK); virtio_blk_free_request(req); } else if (type & VIRTIO_BLK_T_OUT) { - qemu_iovec_init_external(&req->qiov, &req->elem->out_sg[1], - req->elem->out_num - 1); + qemu_iovec_init_external(&req->qiov, &req->elem.out_sg[1], + req->elem.out_num - 1); virtio_blk_handle_write(req, mrb); } else if (type == VIRTIO_BLK_T_IN || type == VIRTIO_BLK_T_BARRIER) { /* VIRTIO_BLK_T_IN is 0, so we can't just & it. */ - qemu_iovec_init_external(&req->qiov, &req->elem->in_sg[0], - req->elem->in_num - 1); + qemu_iovec_init_external(&req->qiov, &req->elem.in_sg[0], + req->elem.in_num - 1); virtio_blk_handle_read(req); } else { virtio_blk_req_complete(req, VIRTIO_BLK_S_UNSUPP); @@ -629,7 +627,7 @@ static void virtio_blk_save_device(VirtIODevice *vdev, QEMUFile *f) while (req) { qemu_put_sbyte(f, 1); - qemu_put_buffer(f, (unsigned char *)req->elem, + qemu_put_buffer(f, (unsigned char *)&req->elem, sizeof(VirtQueueElement)); req = req->next; } @@ -654,15 +652,15 @@ static int virtio_blk_load_device(VirtIODevice *vdev, QEMUFile *f, while (qemu_get_sbyte(f)) { VirtIOBlockReq *req = virtio_blk_alloc_request(s); - qemu_get_buffer(f, (unsigned char *)req->elem, + qemu_get_buffer(f, (unsigned char *)&req->elem, sizeof(VirtQueueElement)); req->next = s->rq; s->rq = req; - virtqueue_map_sg(req->elem->in_sg, req->elem->in_addr, - req->elem->in_num, 1); - virtqueue_map_sg(req->elem->out_sg, req->elem->out_addr, - req->elem->out_num, 0); + virtqueue_map_sg(req->elem.in_sg, req->elem.in_addr, + req->elem.in_num, 1); + virtqueue_map_sg(req->elem.out_sg, req->elem.out_addr, + req->elem.out_num, 0); } return 0; diff --git a/hw/virtio/dataplane/vring.c b/hw/virtio/dataplane/vring.c index 5d17d39c17..67cb2b823e 100644 --- a/hw/virtio/dataplane/vring.c +++ b/hw/virtio/dataplane/vring.c @@ -301,14 +301,16 @@ static void vring_unmap_element(VirtQueueElement *elem) * Stolen from linux/drivers/vhost/vhost.c. */ int vring_pop(VirtIODevice *vdev, Vring *vring, - VirtQueueElement **p_elem) + VirtQueueElement *elem) { struct vring_desc desc; unsigned int i, head, found = 0, num = vring->vr.num; uint16_t avail_idx, last_avail_idx; - VirtQueueElement *elem = NULL; int ret; + /* Initialize elem so it can be safely unmapped */ + elem->in_num = elem->out_num = 0; + /* If there was a fatal error then refuse operation */ if (vring->broken) { ret = -EFAULT; @@ -340,10 +342,8 @@ int vring_pop(VirtIODevice *vdev, Vring *vring, * the index we've seen. */ head = vring->vr.avail->ring[last_avail_idx % num]; - elem = g_slice_new(VirtQueueElement); elem->index = head; - elem->in_num = elem->out_num = 0; - + /* If their number is silly, that's an error. */ if (unlikely(head >= num)) { error_report("Guest says index %u > %u is available", head, num); @@ -391,7 +391,6 @@ int vring_pop(VirtIODevice *vdev, Vring *vring, /* On success, increment avail index. */ vring->last_avail_idx++; - *p_elem = elem; return head; out: @@ -399,11 +398,7 @@ out: if (ret == -EFAULT) { vring->broken = true; } - if (elem) { - vring_unmap_element(elem); - g_slice_free(VirtQueueElement, elem); - } - *p_elem = NULL; + vring_unmap_element(elem); return ret; } diff --git a/include/hw/virtio/dataplane/vring.h b/include/hw/virtio/dataplane/vring.h index b23edd276b..af73ee2ae3 100644 --- a/include/hw/virtio/dataplane/vring.h +++ b/include/hw/virtio/dataplane/vring.h @@ -53,7 +53,7 @@ void vring_teardown(Vring *vring, VirtIODevice *vdev, int n); void vring_disable_notification(VirtIODevice *vdev, Vring *vring); bool vring_enable_notification(VirtIODevice *vdev, Vring *vring); bool vring_should_notify(VirtIODevice *vdev, Vring *vring); -int vring_pop(VirtIODevice *vdev, Vring *vring, VirtQueueElement **elem); +int vring_pop(VirtIODevice *vdev, Vring *vring, VirtQueueElement *elem); void vring_push(Vring *vring, VirtQueueElement *elem, int len); #endif /* VRING_H */ diff --git a/include/hw/virtio/virtio-blk.h b/include/hw/virtio/virtio-blk.h index b3080a2144..afb7b8db3a 100644 --- a/include/hw/virtio/virtio-blk.h +++ b/include/hw/virtio/virtio-blk.h @@ -144,7 +144,7 @@ typedef struct MultiReqBuffer { typedef struct VirtIOBlockReq { VirtIOBlock *dev; - VirtQueueElement *elem; + VirtQueueElement elem; struct virtio_blk_inhdr *in; struct virtio_blk_outhdr out; QEMUIOVector qiov; @@ -152,6 +152,10 @@ typedef struct VirtIOBlockReq { BlockAcctCookie acct; } VirtIOBlockReq; +VirtIOBlockReq *virtio_blk_alloc_request(VirtIOBlock *s); + +void virtio_blk_free_request(VirtIOBlockReq *req); + int virtio_blk_handle_scsi_req(VirtIOBlock *blk, VirtQueueElement *elem); |