1433fc58eSAsias He /* 2433fc58eSAsias He * vhost transport for vsock 3433fc58eSAsias He * 4433fc58eSAsias He * Copyright (C) 2013-2015 Red Hat, Inc. 5433fc58eSAsias He * Author: Asias He <asias@redhat.com> 6433fc58eSAsias He * Stefan Hajnoczi <stefanha@redhat.com> 7433fc58eSAsias He * 8433fc58eSAsias He * This work is licensed under the terms of the GNU GPL, version 2. 9433fc58eSAsias He */ 10433fc58eSAsias He #include <linux/miscdevice.h> 11433fc58eSAsias He #include <linux/atomic.h> 12433fc58eSAsias He #include <linux/module.h> 13433fc58eSAsias He #include <linux/mutex.h> 14433fc58eSAsias He #include <linux/vmalloc.h> 15433fc58eSAsias He #include <net/sock.h> 16433fc58eSAsias He #include <linux/virtio_vsock.h> 17433fc58eSAsias He #include <linux/vhost.h> 18*834e772cSStefan Hajnoczi #include <linux/hashtable.h> 19433fc58eSAsias He 20433fc58eSAsias He #include <net/af_vsock.h> 21433fc58eSAsias He #include "vhost.h" 22433fc58eSAsias He 23433fc58eSAsias He #define VHOST_VSOCK_DEFAULT_HOST_CID 2 24433fc58eSAsias He 25433fc58eSAsias He enum { 26433fc58eSAsias He VHOST_VSOCK_FEATURES = VHOST_FEATURES, 27433fc58eSAsias He }; 28433fc58eSAsias He 29433fc58eSAsias He /* Used to track all the vhost_vsock instances on the system. */ 30433fc58eSAsias He static DEFINE_SPINLOCK(vhost_vsock_lock); 31*834e772cSStefan Hajnoczi static DEFINE_READ_MOSTLY_HASHTABLE(vhost_vsock_hash, 8); 32433fc58eSAsias He 33433fc58eSAsias He struct vhost_vsock { 34433fc58eSAsias He struct vhost_dev dev; 35433fc58eSAsias He struct vhost_virtqueue vqs[2]; 36433fc58eSAsias He 37*834e772cSStefan Hajnoczi /* Link to global vhost_vsock_hash, writes use vhost_vsock_lock */ 38*834e772cSStefan Hajnoczi struct hlist_node hash; 39433fc58eSAsias He 40433fc58eSAsias He struct vhost_work send_pkt_work; 41433fc58eSAsias He spinlock_t send_pkt_list_lock; 42433fc58eSAsias He struct list_head send_pkt_list; /* host->guest pending packets */ 43433fc58eSAsias He 44433fc58eSAsias He atomic_t queued_replies; 45433fc58eSAsias He 46433fc58eSAsias He u32 guest_cid; 47433fc58eSAsias He }; 48433fc58eSAsias He 49433fc58eSAsias He static u32 vhost_transport_get_local_cid(void) 50433fc58eSAsias He { 51433fc58eSAsias He return VHOST_VSOCK_DEFAULT_HOST_CID; 52433fc58eSAsias He } 53433fc58eSAsias He 54*834e772cSStefan Hajnoczi /* Callers that dereference the return value must hold vhost_vsock_lock or the 55*834e772cSStefan Hajnoczi * RCU read lock. 56*834e772cSStefan Hajnoczi */ 57*834e772cSStefan Hajnoczi static struct vhost_vsock *vhost_vsock_get(u32 guest_cid) 58433fc58eSAsias He { 59433fc58eSAsias He struct vhost_vsock *vsock; 60433fc58eSAsias He 61*834e772cSStefan Hajnoczi hash_for_each_possible_rcu(vhost_vsock_hash, vsock, hash, guest_cid) { 62433fc58eSAsias He u32 other_cid = vsock->guest_cid; 63433fc58eSAsias He 64433fc58eSAsias He /* Skip instances that have no CID yet */ 65433fc58eSAsias He if (other_cid == 0) 66433fc58eSAsias He continue; 67433fc58eSAsias He 68ff3c1b1aSVaibhav Murkute if (other_cid == guest_cid) 69433fc58eSAsias He return vsock; 70ff3c1b1aSVaibhav Murkute 71433fc58eSAsias He } 72433fc58eSAsias He 73433fc58eSAsias He return NULL; 74433fc58eSAsias He } 75433fc58eSAsias He 76433fc58eSAsias He static void 77433fc58eSAsias He vhost_transport_do_send_pkt(struct vhost_vsock *vsock, 78433fc58eSAsias He struct vhost_virtqueue *vq) 79433fc58eSAsias He { 80433fc58eSAsias He struct vhost_virtqueue *tx_vq = &vsock->vqs[VSOCK_VQ_TX]; 81433fc58eSAsias He bool added = false; 82433fc58eSAsias He bool restart_tx = false; 83433fc58eSAsias He 84433fc58eSAsias He mutex_lock(&vq->mutex); 85433fc58eSAsias He 86433fc58eSAsias He if (!vq->private_data) 87433fc58eSAsias He goto out; 88433fc58eSAsias He 89433fc58eSAsias He /* Avoid further vmexits, we're already processing the virtqueue */ 90433fc58eSAsias He vhost_disable_notify(&vsock->dev, vq); 91433fc58eSAsias He 92433fc58eSAsias He for (;;) { 93433fc58eSAsias He struct virtio_vsock_pkt *pkt; 94433fc58eSAsias He struct iov_iter iov_iter; 95433fc58eSAsias He unsigned out, in; 96433fc58eSAsias He size_t nbytes; 97433fc58eSAsias He size_t len; 98433fc58eSAsias He int head; 99433fc58eSAsias He 100433fc58eSAsias He spin_lock_bh(&vsock->send_pkt_list_lock); 101433fc58eSAsias He if (list_empty(&vsock->send_pkt_list)) { 102433fc58eSAsias He spin_unlock_bh(&vsock->send_pkt_list_lock); 103433fc58eSAsias He vhost_enable_notify(&vsock->dev, vq); 104433fc58eSAsias He break; 105433fc58eSAsias He } 106433fc58eSAsias He 107433fc58eSAsias He pkt = list_first_entry(&vsock->send_pkt_list, 108433fc58eSAsias He struct virtio_vsock_pkt, list); 109433fc58eSAsias He list_del_init(&pkt->list); 110433fc58eSAsias He spin_unlock_bh(&vsock->send_pkt_list_lock); 111433fc58eSAsias He 112433fc58eSAsias He head = vhost_get_vq_desc(vq, vq->iov, ARRAY_SIZE(vq->iov), 113433fc58eSAsias He &out, &in, NULL, NULL); 114433fc58eSAsias He if (head < 0) { 115433fc58eSAsias He spin_lock_bh(&vsock->send_pkt_list_lock); 116433fc58eSAsias He list_add(&pkt->list, &vsock->send_pkt_list); 117433fc58eSAsias He spin_unlock_bh(&vsock->send_pkt_list_lock); 118433fc58eSAsias He break; 119433fc58eSAsias He } 120433fc58eSAsias He 121433fc58eSAsias He if (head == vq->num) { 122433fc58eSAsias He spin_lock_bh(&vsock->send_pkt_list_lock); 123433fc58eSAsias He list_add(&pkt->list, &vsock->send_pkt_list); 124433fc58eSAsias He spin_unlock_bh(&vsock->send_pkt_list_lock); 125433fc58eSAsias He 126433fc58eSAsias He /* We cannot finish yet if more buffers snuck in while 127433fc58eSAsias He * re-enabling notify. 128433fc58eSAsias He */ 129433fc58eSAsias He if (unlikely(vhost_enable_notify(&vsock->dev, vq))) { 130433fc58eSAsias He vhost_disable_notify(&vsock->dev, vq); 131433fc58eSAsias He continue; 132433fc58eSAsias He } 133433fc58eSAsias He break; 134433fc58eSAsias He } 135433fc58eSAsias He 136433fc58eSAsias He if (out) { 137433fc58eSAsias He virtio_transport_free_pkt(pkt); 138433fc58eSAsias He vq_err(vq, "Expected 0 output buffers, got %u\n", out); 139433fc58eSAsias He break; 140433fc58eSAsias He } 141433fc58eSAsias He 142433fc58eSAsias He len = iov_length(&vq->iov[out], in); 143433fc58eSAsias He iov_iter_init(&iov_iter, READ, &vq->iov[out], in, len); 144433fc58eSAsias He 145433fc58eSAsias He nbytes = copy_to_iter(&pkt->hdr, sizeof(pkt->hdr), &iov_iter); 146433fc58eSAsias He if (nbytes != sizeof(pkt->hdr)) { 147433fc58eSAsias He virtio_transport_free_pkt(pkt); 148433fc58eSAsias He vq_err(vq, "Faulted on copying pkt hdr\n"); 149433fc58eSAsias He break; 150433fc58eSAsias He } 151433fc58eSAsias He 152433fc58eSAsias He nbytes = copy_to_iter(pkt->buf, pkt->len, &iov_iter); 153433fc58eSAsias He if (nbytes != pkt->len) { 154433fc58eSAsias He virtio_transport_free_pkt(pkt); 155433fc58eSAsias He vq_err(vq, "Faulted on copying pkt buf\n"); 156433fc58eSAsias He break; 157433fc58eSAsias He } 158433fc58eSAsias He 159433fc58eSAsias He vhost_add_used(vq, head, sizeof(pkt->hdr) + pkt->len); 160433fc58eSAsias He added = true; 161433fc58eSAsias He 162433fc58eSAsias He if (pkt->reply) { 163433fc58eSAsias He int val; 164433fc58eSAsias He 165433fc58eSAsias He val = atomic_dec_return(&vsock->queued_replies); 166433fc58eSAsias He 167433fc58eSAsias He /* Do we have resources to resume tx processing? */ 168433fc58eSAsias He if (val + 1 == tx_vq->num) 169433fc58eSAsias He restart_tx = true; 170433fc58eSAsias He } 171433fc58eSAsias He 17282dfb540SGerard Garcia /* Deliver to monitoring devices all correctly transmitted 17382dfb540SGerard Garcia * packets. 17482dfb540SGerard Garcia */ 17582dfb540SGerard Garcia virtio_transport_deliver_tap_pkt(pkt); 17682dfb540SGerard Garcia 177433fc58eSAsias He virtio_transport_free_pkt(pkt); 178433fc58eSAsias He } 179433fc58eSAsias He if (added) 180433fc58eSAsias He vhost_signal(&vsock->dev, vq); 181433fc58eSAsias He 182433fc58eSAsias He out: 183433fc58eSAsias He mutex_unlock(&vq->mutex); 184433fc58eSAsias He 185433fc58eSAsias He if (restart_tx) 186433fc58eSAsias He vhost_poll_queue(&tx_vq->poll); 187433fc58eSAsias He } 188433fc58eSAsias He 189433fc58eSAsias He static void vhost_transport_send_pkt_work(struct vhost_work *work) 190433fc58eSAsias He { 191433fc58eSAsias He struct vhost_virtqueue *vq; 192433fc58eSAsias He struct vhost_vsock *vsock; 193433fc58eSAsias He 194433fc58eSAsias He vsock = container_of(work, struct vhost_vsock, send_pkt_work); 195433fc58eSAsias He vq = &vsock->vqs[VSOCK_VQ_RX]; 196433fc58eSAsias He 197433fc58eSAsias He vhost_transport_do_send_pkt(vsock, vq); 198433fc58eSAsias He } 199433fc58eSAsias He 200433fc58eSAsias He static int 201433fc58eSAsias He vhost_transport_send_pkt(struct virtio_vsock_pkt *pkt) 202433fc58eSAsias He { 203433fc58eSAsias He struct vhost_vsock *vsock; 204433fc58eSAsias He int len = pkt->len; 205433fc58eSAsias He 206*834e772cSStefan Hajnoczi rcu_read_lock(); 207*834e772cSStefan Hajnoczi 208433fc58eSAsias He /* Find the vhost_vsock according to guest context id */ 209433fc58eSAsias He vsock = vhost_vsock_get(le64_to_cpu(pkt->hdr.dst_cid)); 210433fc58eSAsias He if (!vsock) { 211*834e772cSStefan Hajnoczi rcu_read_unlock(); 212433fc58eSAsias He virtio_transport_free_pkt(pkt); 213433fc58eSAsias He return -ENODEV; 214433fc58eSAsias He } 215433fc58eSAsias He 216433fc58eSAsias He if (pkt->reply) 217433fc58eSAsias He atomic_inc(&vsock->queued_replies); 218433fc58eSAsias He 219433fc58eSAsias He spin_lock_bh(&vsock->send_pkt_list_lock); 220433fc58eSAsias He list_add_tail(&pkt->list, &vsock->send_pkt_list); 221433fc58eSAsias He spin_unlock_bh(&vsock->send_pkt_list_lock); 222433fc58eSAsias He 223433fc58eSAsias He vhost_work_queue(&vsock->dev, &vsock->send_pkt_work); 224*834e772cSStefan Hajnoczi 225*834e772cSStefan Hajnoczi rcu_read_unlock(); 226433fc58eSAsias He return len; 227433fc58eSAsias He } 228433fc58eSAsias He 22916320f36SPeng Tao static int 23016320f36SPeng Tao vhost_transport_cancel_pkt(struct vsock_sock *vsk) 23116320f36SPeng Tao { 23216320f36SPeng Tao struct vhost_vsock *vsock; 23316320f36SPeng Tao struct virtio_vsock_pkt *pkt, *n; 23416320f36SPeng Tao int cnt = 0; 235*834e772cSStefan Hajnoczi int ret = -ENODEV; 23616320f36SPeng Tao LIST_HEAD(freeme); 23716320f36SPeng Tao 238*834e772cSStefan Hajnoczi rcu_read_lock(); 239*834e772cSStefan Hajnoczi 24016320f36SPeng Tao /* Find the vhost_vsock according to guest context id */ 24116320f36SPeng Tao vsock = vhost_vsock_get(vsk->remote_addr.svm_cid); 24216320f36SPeng Tao if (!vsock) 243*834e772cSStefan Hajnoczi goto out; 24416320f36SPeng Tao 24516320f36SPeng Tao spin_lock_bh(&vsock->send_pkt_list_lock); 24616320f36SPeng Tao list_for_each_entry_safe(pkt, n, &vsock->send_pkt_list, list) { 24716320f36SPeng Tao if (pkt->vsk != vsk) 24816320f36SPeng Tao continue; 24916320f36SPeng Tao list_move(&pkt->list, &freeme); 25016320f36SPeng Tao } 25116320f36SPeng Tao spin_unlock_bh(&vsock->send_pkt_list_lock); 25216320f36SPeng Tao 25316320f36SPeng Tao list_for_each_entry_safe(pkt, n, &freeme, list) { 25416320f36SPeng Tao if (pkt->reply) 25516320f36SPeng Tao cnt++; 25616320f36SPeng Tao list_del(&pkt->list); 25716320f36SPeng Tao virtio_transport_free_pkt(pkt); 25816320f36SPeng Tao } 25916320f36SPeng Tao 26016320f36SPeng Tao if (cnt) { 26116320f36SPeng Tao struct vhost_virtqueue *tx_vq = &vsock->vqs[VSOCK_VQ_TX]; 26216320f36SPeng Tao int new_cnt; 26316320f36SPeng Tao 26416320f36SPeng Tao new_cnt = atomic_sub_return(cnt, &vsock->queued_replies); 26516320f36SPeng Tao if (new_cnt + cnt >= tx_vq->num && new_cnt < tx_vq->num) 26616320f36SPeng Tao vhost_poll_queue(&tx_vq->poll); 26716320f36SPeng Tao } 26816320f36SPeng Tao 269*834e772cSStefan Hajnoczi ret = 0; 270*834e772cSStefan Hajnoczi out: 271*834e772cSStefan Hajnoczi rcu_read_unlock(); 272*834e772cSStefan Hajnoczi return ret; 27316320f36SPeng Tao } 27416320f36SPeng Tao 275433fc58eSAsias He static struct virtio_vsock_pkt * 276433fc58eSAsias He vhost_vsock_alloc_pkt(struct vhost_virtqueue *vq, 277433fc58eSAsias He unsigned int out, unsigned int in) 278433fc58eSAsias He { 279433fc58eSAsias He struct virtio_vsock_pkt *pkt; 280433fc58eSAsias He struct iov_iter iov_iter; 281433fc58eSAsias He size_t nbytes; 282433fc58eSAsias He size_t len; 283433fc58eSAsias He 284433fc58eSAsias He if (in != 0) { 285433fc58eSAsias He vq_err(vq, "Expected 0 input buffers, got %u\n", in); 286433fc58eSAsias He return NULL; 287433fc58eSAsias He } 288433fc58eSAsias He 289433fc58eSAsias He pkt = kzalloc(sizeof(*pkt), GFP_KERNEL); 290433fc58eSAsias He if (!pkt) 291433fc58eSAsias He return NULL; 292433fc58eSAsias He 293433fc58eSAsias He len = iov_length(vq->iov, out); 294433fc58eSAsias He iov_iter_init(&iov_iter, WRITE, vq->iov, out, len); 295433fc58eSAsias He 296433fc58eSAsias He nbytes = copy_from_iter(&pkt->hdr, sizeof(pkt->hdr), &iov_iter); 297433fc58eSAsias He if (nbytes != sizeof(pkt->hdr)) { 298433fc58eSAsias He vq_err(vq, "Expected %zu bytes for pkt->hdr, got %zu bytes\n", 299433fc58eSAsias He sizeof(pkt->hdr), nbytes); 300433fc58eSAsias He kfree(pkt); 301433fc58eSAsias He return NULL; 302433fc58eSAsias He } 303433fc58eSAsias He 304433fc58eSAsias He if (le16_to_cpu(pkt->hdr.type) == VIRTIO_VSOCK_TYPE_STREAM) 305433fc58eSAsias He pkt->len = le32_to_cpu(pkt->hdr.len); 306433fc58eSAsias He 307433fc58eSAsias He /* No payload */ 308433fc58eSAsias He if (!pkt->len) 309433fc58eSAsias He return pkt; 310433fc58eSAsias He 311433fc58eSAsias He /* The pkt is too big */ 312433fc58eSAsias He if (pkt->len > VIRTIO_VSOCK_MAX_PKT_BUF_SIZE) { 313433fc58eSAsias He kfree(pkt); 314433fc58eSAsias He return NULL; 315433fc58eSAsias He } 316433fc58eSAsias He 317433fc58eSAsias He pkt->buf = kmalloc(pkt->len, GFP_KERNEL); 318433fc58eSAsias He if (!pkt->buf) { 319433fc58eSAsias He kfree(pkt); 320433fc58eSAsias He return NULL; 321433fc58eSAsias He } 322433fc58eSAsias He 323433fc58eSAsias He nbytes = copy_from_iter(pkt->buf, pkt->len, &iov_iter); 324433fc58eSAsias He if (nbytes != pkt->len) { 325433fc58eSAsias He vq_err(vq, "Expected %u byte payload, got %zu bytes\n", 326433fc58eSAsias He pkt->len, nbytes); 327433fc58eSAsias He virtio_transport_free_pkt(pkt); 328433fc58eSAsias He return NULL; 329433fc58eSAsias He } 330433fc58eSAsias He 331433fc58eSAsias He return pkt; 332433fc58eSAsias He } 333433fc58eSAsias He 334433fc58eSAsias He /* Is there space left for replies to rx packets? */ 335433fc58eSAsias He static bool vhost_vsock_more_replies(struct vhost_vsock *vsock) 336433fc58eSAsias He { 337433fc58eSAsias He struct vhost_virtqueue *vq = &vsock->vqs[VSOCK_VQ_TX]; 338433fc58eSAsias He int val; 339433fc58eSAsias He 340433fc58eSAsias He smp_rmb(); /* paired with atomic_inc() and atomic_dec_return() */ 341433fc58eSAsias He val = atomic_read(&vsock->queued_replies); 342433fc58eSAsias He 343433fc58eSAsias He return val < vq->num; 344433fc58eSAsias He } 345433fc58eSAsias He 346433fc58eSAsias He static void vhost_vsock_handle_tx_kick(struct vhost_work *work) 347433fc58eSAsias He { 348433fc58eSAsias He struct vhost_virtqueue *vq = container_of(work, struct vhost_virtqueue, 349433fc58eSAsias He poll.work); 350433fc58eSAsias He struct vhost_vsock *vsock = container_of(vq->dev, struct vhost_vsock, 351433fc58eSAsias He dev); 352433fc58eSAsias He struct virtio_vsock_pkt *pkt; 353433fc58eSAsias He int head; 354433fc58eSAsias He unsigned int out, in; 355433fc58eSAsias He bool added = false; 356433fc58eSAsias He 357433fc58eSAsias He mutex_lock(&vq->mutex); 358433fc58eSAsias He 359433fc58eSAsias He if (!vq->private_data) 360433fc58eSAsias He goto out; 361433fc58eSAsias He 362433fc58eSAsias He vhost_disable_notify(&vsock->dev, vq); 363433fc58eSAsias He for (;;) { 3643fda5d6eSStefan Hajnoczi u32 len; 3653fda5d6eSStefan Hajnoczi 366433fc58eSAsias He if (!vhost_vsock_more_replies(vsock)) { 367433fc58eSAsias He /* Stop tx until the device processes already 368433fc58eSAsias He * pending replies. Leave tx virtqueue 369433fc58eSAsias He * callbacks disabled. 370433fc58eSAsias He */ 371433fc58eSAsias He goto no_more_replies; 372433fc58eSAsias He } 373433fc58eSAsias He 374433fc58eSAsias He head = vhost_get_vq_desc(vq, vq->iov, ARRAY_SIZE(vq->iov), 375433fc58eSAsias He &out, &in, NULL, NULL); 376433fc58eSAsias He if (head < 0) 377433fc58eSAsias He break; 378433fc58eSAsias He 379433fc58eSAsias He if (head == vq->num) { 380433fc58eSAsias He if (unlikely(vhost_enable_notify(&vsock->dev, vq))) { 381433fc58eSAsias He vhost_disable_notify(&vsock->dev, vq); 382433fc58eSAsias He continue; 383433fc58eSAsias He } 384433fc58eSAsias He break; 385433fc58eSAsias He } 386433fc58eSAsias He 387433fc58eSAsias He pkt = vhost_vsock_alloc_pkt(vq, out, in); 388433fc58eSAsias He if (!pkt) { 389433fc58eSAsias He vq_err(vq, "Faulted on pkt\n"); 390433fc58eSAsias He continue; 391433fc58eSAsias He } 392433fc58eSAsias He 3933fda5d6eSStefan Hajnoczi len = pkt->len; 3943fda5d6eSStefan Hajnoczi 39582dfb540SGerard Garcia /* Deliver to monitoring devices all received packets */ 39682dfb540SGerard Garcia virtio_transport_deliver_tap_pkt(pkt); 39782dfb540SGerard Garcia 398433fc58eSAsias He /* Only accept correctly addressed packets */ 399433fc58eSAsias He if (le64_to_cpu(pkt->hdr.src_cid) == vsock->guest_cid) 400433fc58eSAsias He virtio_transport_recv_pkt(pkt); 401433fc58eSAsias He else 402433fc58eSAsias He virtio_transport_free_pkt(pkt); 403433fc58eSAsias He 4043fda5d6eSStefan Hajnoczi vhost_add_used(vq, head, sizeof(pkt->hdr) + len); 405433fc58eSAsias He added = true; 406433fc58eSAsias He } 407433fc58eSAsias He 408433fc58eSAsias He no_more_replies: 409433fc58eSAsias He if (added) 410433fc58eSAsias He vhost_signal(&vsock->dev, vq); 411433fc58eSAsias He 412433fc58eSAsias He out: 413433fc58eSAsias He mutex_unlock(&vq->mutex); 414433fc58eSAsias He } 415433fc58eSAsias He 416433fc58eSAsias He static void vhost_vsock_handle_rx_kick(struct vhost_work *work) 417433fc58eSAsias He { 418433fc58eSAsias He struct vhost_virtqueue *vq = container_of(work, struct vhost_virtqueue, 419433fc58eSAsias He poll.work); 420433fc58eSAsias He struct vhost_vsock *vsock = container_of(vq->dev, struct vhost_vsock, 421433fc58eSAsias He dev); 422433fc58eSAsias He 423433fc58eSAsias He vhost_transport_do_send_pkt(vsock, vq); 424433fc58eSAsias He } 425433fc58eSAsias He 426433fc58eSAsias He static int vhost_vsock_start(struct vhost_vsock *vsock) 427433fc58eSAsias He { 4280516ffd8SStefan Hajnoczi struct vhost_virtqueue *vq; 429433fc58eSAsias He size_t i; 430433fc58eSAsias He int ret; 431433fc58eSAsias He 432433fc58eSAsias He mutex_lock(&vsock->dev.mutex); 433433fc58eSAsias He 434433fc58eSAsias He ret = vhost_dev_check_owner(&vsock->dev); 435433fc58eSAsias He if (ret) 436433fc58eSAsias He goto err; 437433fc58eSAsias He 438433fc58eSAsias He for (i = 0; i < ARRAY_SIZE(vsock->vqs); i++) { 4390516ffd8SStefan Hajnoczi vq = &vsock->vqs[i]; 440433fc58eSAsias He 441433fc58eSAsias He mutex_lock(&vq->mutex); 442433fc58eSAsias He 443433fc58eSAsias He if (!vhost_vq_access_ok(vq)) { 444433fc58eSAsias He ret = -EFAULT; 445433fc58eSAsias He goto err_vq; 446433fc58eSAsias He } 447433fc58eSAsias He 448433fc58eSAsias He if (!vq->private_data) { 449433fc58eSAsias He vq->private_data = vsock; 4500516ffd8SStefan Hajnoczi ret = vhost_vq_init_access(vq); 4510516ffd8SStefan Hajnoczi if (ret) 4520516ffd8SStefan Hajnoczi goto err_vq; 453433fc58eSAsias He } 454433fc58eSAsias He 455433fc58eSAsias He mutex_unlock(&vq->mutex); 456433fc58eSAsias He } 457433fc58eSAsias He 458433fc58eSAsias He mutex_unlock(&vsock->dev.mutex); 459433fc58eSAsias He return 0; 460433fc58eSAsias He 461433fc58eSAsias He err_vq: 4620516ffd8SStefan Hajnoczi vq->private_data = NULL; 4630516ffd8SStefan Hajnoczi mutex_unlock(&vq->mutex); 4640516ffd8SStefan Hajnoczi 465433fc58eSAsias He for (i = 0; i < ARRAY_SIZE(vsock->vqs); i++) { 4660516ffd8SStefan Hajnoczi vq = &vsock->vqs[i]; 467433fc58eSAsias He 468433fc58eSAsias He mutex_lock(&vq->mutex); 469433fc58eSAsias He vq->private_data = NULL; 470433fc58eSAsias He mutex_unlock(&vq->mutex); 471433fc58eSAsias He } 472433fc58eSAsias He err: 473433fc58eSAsias He mutex_unlock(&vsock->dev.mutex); 474433fc58eSAsias He return ret; 475433fc58eSAsias He } 476433fc58eSAsias He 477433fc58eSAsias He static int vhost_vsock_stop(struct vhost_vsock *vsock) 478433fc58eSAsias He { 479433fc58eSAsias He size_t i; 480433fc58eSAsias He int ret; 481433fc58eSAsias He 482433fc58eSAsias He mutex_lock(&vsock->dev.mutex); 483433fc58eSAsias He 484433fc58eSAsias He ret = vhost_dev_check_owner(&vsock->dev); 485433fc58eSAsias He if (ret) 486433fc58eSAsias He goto err; 487433fc58eSAsias He 488433fc58eSAsias He for (i = 0; i < ARRAY_SIZE(vsock->vqs); i++) { 489433fc58eSAsias He struct vhost_virtqueue *vq = &vsock->vqs[i]; 490433fc58eSAsias He 491433fc58eSAsias He mutex_lock(&vq->mutex); 492433fc58eSAsias He vq->private_data = NULL; 493433fc58eSAsias He mutex_unlock(&vq->mutex); 494433fc58eSAsias He } 495433fc58eSAsias He 496433fc58eSAsias He err: 497433fc58eSAsias He mutex_unlock(&vsock->dev.mutex); 498433fc58eSAsias He return ret; 499433fc58eSAsias He } 500433fc58eSAsias He 501433fc58eSAsias He static void vhost_vsock_free(struct vhost_vsock *vsock) 502433fc58eSAsias He { 503b226acabSWei Yongjun kvfree(vsock); 504433fc58eSAsias He } 505433fc58eSAsias He 506433fc58eSAsias He static int vhost_vsock_dev_open(struct inode *inode, struct file *file) 507433fc58eSAsias He { 508433fc58eSAsias He struct vhost_virtqueue **vqs; 509433fc58eSAsias He struct vhost_vsock *vsock; 510433fc58eSAsias He int ret; 511433fc58eSAsias He 512433fc58eSAsias He /* This struct is large and allocation could fail, fall back to vmalloc 513433fc58eSAsias He * if there is no other way. 514433fc58eSAsias He */ 515dcda9b04SMichal Hocko vsock = kvmalloc(sizeof(*vsock), GFP_KERNEL | __GFP_RETRY_MAYFAIL); 516433fc58eSAsias He if (!vsock) 517433fc58eSAsias He return -ENOMEM; 518433fc58eSAsias He 519433fc58eSAsias He vqs = kmalloc_array(ARRAY_SIZE(vsock->vqs), sizeof(*vqs), GFP_KERNEL); 520433fc58eSAsias He if (!vqs) { 521433fc58eSAsias He ret = -ENOMEM; 522433fc58eSAsias He goto out; 523433fc58eSAsias He } 524433fc58eSAsias He 525a72b69dcSStefan Hajnoczi vsock->guest_cid = 0; /* no CID assigned yet */ 526a72b69dcSStefan Hajnoczi 527433fc58eSAsias He atomic_set(&vsock->queued_replies, 0); 528433fc58eSAsias He 529433fc58eSAsias He vqs[VSOCK_VQ_TX] = &vsock->vqs[VSOCK_VQ_TX]; 530433fc58eSAsias He vqs[VSOCK_VQ_RX] = &vsock->vqs[VSOCK_VQ_RX]; 531433fc58eSAsias He vsock->vqs[VSOCK_VQ_TX].handle_kick = vhost_vsock_handle_tx_kick; 532433fc58eSAsias He vsock->vqs[VSOCK_VQ_RX].handle_kick = vhost_vsock_handle_rx_kick; 533433fc58eSAsias He 534433fc58eSAsias He vhost_dev_init(&vsock->dev, vqs, ARRAY_SIZE(vsock->vqs)); 535433fc58eSAsias He 536433fc58eSAsias He file->private_data = vsock; 537433fc58eSAsias He spin_lock_init(&vsock->send_pkt_list_lock); 538433fc58eSAsias He INIT_LIST_HEAD(&vsock->send_pkt_list); 539433fc58eSAsias He vhost_work_init(&vsock->send_pkt_work, vhost_transport_send_pkt_work); 540433fc58eSAsias He return 0; 541433fc58eSAsias He 542433fc58eSAsias He out: 543433fc58eSAsias He vhost_vsock_free(vsock); 544433fc58eSAsias He return ret; 545433fc58eSAsias He } 546433fc58eSAsias He 547433fc58eSAsias He static void vhost_vsock_flush(struct vhost_vsock *vsock) 548433fc58eSAsias He { 549433fc58eSAsias He int i; 550433fc58eSAsias He 551433fc58eSAsias He for (i = 0; i < ARRAY_SIZE(vsock->vqs); i++) 552433fc58eSAsias He if (vsock->vqs[i].handle_kick) 553433fc58eSAsias He vhost_poll_flush(&vsock->vqs[i].poll); 554433fc58eSAsias He vhost_work_flush(&vsock->dev, &vsock->send_pkt_work); 555433fc58eSAsias He } 556433fc58eSAsias He 557433fc58eSAsias He static void vhost_vsock_reset_orphans(struct sock *sk) 558433fc58eSAsias He { 559433fc58eSAsias He struct vsock_sock *vsk = vsock_sk(sk); 560433fc58eSAsias He 561433fc58eSAsias He /* vmci_transport.c doesn't take sk_lock here either. At least we're 562433fc58eSAsias He * under vsock_table_lock so the sock cannot disappear while we're 563433fc58eSAsias He * executing. 564433fc58eSAsias He */ 565433fc58eSAsias He 566c38f57daSStefan Hajnoczi /* If the peer is still valid, no need to reset connection */ 567c38f57daSStefan Hajnoczi if (vhost_vsock_get(vsk->remote_addr.svm_cid)) 568c38f57daSStefan Hajnoczi return; 569c38f57daSStefan Hajnoczi 570c38f57daSStefan Hajnoczi /* If the close timeout is pending, let it expire. This avoids races 571c38f57daSStefan Hajnoczi * with the timeout callback. 572c38f57daSStefan Hajnoczi */ 573c38f57daSStefan Hajnoczi if (vsk->close_work_scheduled) 574c38f57daSStefan Hajnoczi return; 575c38f57daSStefan Hajnoczi 576433fc58eSAsias He sock_set_flag(sk, SOCK_DONE); 577433fc58eSAsias He vsk->peer_shutdown = SHUTDOWN_MASK; 578433fc58eSAsias He sk->sk_state = SS_UNCONNECTED; 579433fc58eSAsias He sk->sk_err = ECONNRESET; 580433fc58eSAsias He sk->sk_error_report(sk); 581433fc58eSAsias He } 582433fc58eSAsias He 583433fc58eSAsias He static int vhost_vsock_dev_release(struct inode *inode, struct file *file) 584433fc58eSAsias He { 585433fc58eSAsias He struct vhost_vsock *vsock = file->private_data; 586433fc58eSAsias He 587433fc58eSAsias He spin_lock_bh(&vhost_vsock_lock); 588*834e772cSStefan Hajnoczi if (vsock->guest_cid) 589*834e772cSStefan Hajnoczi hash_del_rcu(&vsock->hash); 590433fc58eSAsias He spin_unlock_bh(&vhost_vsock_lock); 591433fc58eSAsias He 592*834e772cSStefan Hajnoczi /* Wait for other CPUs to finish using vsock */ 593*834e772cSStefan Hajnoczi synchronize_rcu(); 594*834e772cSStefan Hajnoczi 595433fc58eSAsias He /* Iterating over all connections for all CIDs to find orphans is 596433fc58eSAsias He * inefficient. Room for improvement here. */ 597433fc58eSAsias He vsock_for_each_connected_socket(vhost_vsock_reset_orphans); 598433fc58eSAsias He 599433fc58eSAsias He vhost_vsock_stop(vsock); 600433fc58eSAsias He vhost_vsock_flush(vsock); 601433fc58eSAsias He vhost_dev_stop(&vsock->dev); 602433fc58eSAsias He 603433fc58eSAsias He spin_lock_bh(&vsock->send_pkt_list_lock); 604433fc58eSAsias He while (!list_empty(&vsock->send_pkt_list)) { 605433fc58eSAsias He struct virtio_vsock_pkt *pkt; 606433fc58eSAsias He 607433fc58eSAsias He pkt = list_first_entry(&vsock->send_pkt_list, 608433fc58eSAsias He struct virtio_vsock_pkt, list); 609433fc58eSAsias He list_del_init(&pkt->list); 610433fc58eSAsias He virtio_transport_free_pkt(pkt); 611433fc58eSAsias He } 612433fc58eSAsias He spin_unlock_bh(&vsock->send_pkt_list_lock); 613433fc58eSAsias He 614f6f93f75S夷则(Caspar) vhost_dev_cleanup(&vsock->dev); 615433fc58eSAsias He kfree(vsock->dev.vqs); 616433fc58eSAsias He vhost_vsock_free(vsock); 617433fc58eSAsias He return 0; 618433fc58eSAsias He } 619433fc58eSAsias He 620433fc58eSAsias He static int vhost_vsock_set_cid(struct vhost_vsock *vsock, u64 guest_cid) 621433fc58eSAsias He { 622433fc58eSAsias He struct vhost_vsock *other; 623433fc58eSAsias He 624433fc58eSAsias He /* Refuse reserved CIDs */ 625433fc58eSAsias He if (guest_cid <= VMADDR_CID_HOST || 626433fc58eSAsias He guest_cid == U32_MAX) 627433fc58eSAsias He return -EINVAL; 628433fc58eSAsias He 629433fc58eSAsias He /* 64-bit CIDs are not yet supported */ 630433fc58eSAsias He if (guest_cid > U32_MAX) 631433fc58eSAsias He return -EINVAL; 632433fc58eSAsias He 633433fc58eSAsias He /* Refuse if CID is already in use */ 634433fc58eSAsias He spin_lock_bh(&vhost_vsock_lock); 635*834e772cSStefan Hajnoczi other = vhost_vsock_get(guest_cid); 6366c083c2bSGao feng if (other && other != vsock) { 6376c083c2bSGao feng spin_unlock_bh(&vhost_vsock_lock); 6386c083c2bSGao feng return -EADDRINUSE; 6396c083c2bSGao feng } 640*834e772cSStefan Hajnoczi 641*834e772cSStefan Hajnoczi if (vsock->guest_cid) 642*834e772cSStefan Hajnoczi hash_del_rcu(&vsock->hash); 643*834e772cSStefan Hajnoczi 644433fc58eSAsias He vsock->guest_cid = guest_cid; 645*834e772cSStefan Hajnoczi hash_add_rcu(vhost_vsock_hash, &vsock->hash, guest_cid); 646433fc58eSAsias He spin_unlock_bh(&vhost_vsock_lock); 647433fc58eSAsias He 648433fc58eSAsias He return 0; 649433fc58eSAsias He } 650433fc58eSAsias He 651433fc58eSAsias He static int vhost_vsock_set_features(struct vhost_vsock *vsock, u64 features) 652433fc58eSAsias He { 653433fc58eSAsias He struct vhost_virtqueue *vq; 654433fc58eSAsias He int i; 655433fc58eSAsias He 656433fc58eSAsias He if (features & ~VHOST_VSOCK_FEATURES) 657433fc58eSAsias He return -EOPNOTSUPP; 658433fc58eSAsias He 659433fc58eSAsias He mutex_lock(&vsock->dev.mutex); 660433fc58eSAsias He if ((features & (1 << VHOST_F_LOG_ALL)) && 661433fc58eSAsias He !vhost_log_access_ok(&vsock->dev)) { 662433fc58eSAsias He mutex_unlock(&vsock->dev.mutex); 663433fc58eSAsias He return -EFAULT; 664433fc58eSAsias He } 665433fc58eSAsias He 666433fc58eSAsias He for (i = 0; i < ARRAY_SIZE(vsock->vqs); i++) { 667433fc58eSAsias He vq = &vsock->vqs[i]; 668433fc58eSAsias He mutex_lock(&vq->mutex); 669433fc58eSAsias He vq->acked_features = features; 670433fc58eSAsias He mutex_unlock(&vq->mutex); 671433fc58eSAsias He } 672433fc58eSAsias He mutex_unlock(&vsock->dev.mutex); 673433fc58eSAsias He return 0; 674433fc58eSAsias He } 675433fc58eSAsias He 676433fc58eSAsias He static long vhost_vsock_dev_ioctl(struct file *f, unsigned int ioctl, 677433fc58eSAsias He unsigned long arg) 678433fc58eSAsias He { 679433fc58eSAsias He struct vhost_vsock *vsock = f->private_data; 680433fc58eSAsias He void __user *argp = (void __user *)arg; 681433fc58eSAsias He u64 guest_cid; 682433fc58eSAsias He u64 features; 683433fc58eSAsias He int start; 684433fc58eSAsias He int r; 685433fc58eSAsias He 686433fc58eSAsias He switch (ioctl) { 687433fc58eSAsias He case VHOST_VSOCK_SET_GUEST_CID: 688433fc58eSAsias He if (copy_from_user(&guest_cid, argp, sizeof(guest_cid))) 689433fc58eSAsias He return -EFAULT; 690433fc58eSAsias He return vhost_vsock_set_cid(vsock, guest_cid); 691433fc58eSAsias He case VHOST_VSOCK_SET_RUNNING: 692433fc58eSAsias He if (copy_from_user(&start, argp, sizeof(start))) 693433fc58eSAsias He return -EFAULT; 694433fc58eSAsias He if (start) 695433fc58eSAsias He return vhost_vsock_start(vsock); 696433fc58eSAsias He else 697433fc58eSAsias He return vhost_vsock_stop(vsock); 698433fc58eSAsias He case VHOST_GET_FEATURES: 699433fc58eSAsias He features = VHOST_VSOCK_FEATURES; 700433fc58eSAsias He if (copy_to_user(argp, &features, sizeof(features))) 701433fc58eSAsias He return -EFAULT; 702433fc58eSAsias He return 0; 703433fc58eSAsias He case VHOST_SET_FEATURES: 704433fc58eSAsias He if (copy_from_user(&features, argp, sizeof(features))) 705433fc58eSAsias He return -EFAULT; 706433fc58eSAsias He return vhost_vsock_set_features(vsock, features); 707433fc58eSAsias He default: 708433fc58eSAsias He mutex_lock(&vsock->dev.mutex); 709433fc58eSAsias He r = vhost_dev_ioctl(&vsock->dev, ioctl, argp); 710433fc58eSAsias He if (r == -ENOIOCTLCMD) 711433fc58eSAsias He r = vhost_vring_ioctl(&vsock->dev, ioctl, argp); 712433fc58eSAsias He else 713433fc58eSAsias He vhost_vsock_flush(vsock); 714433fc58eSAsias He mutex_unlock(&vsock->dev.mutex); 715433fc58eSAsias He return r; 716433fc58eSAsias He } 717433fc58eSAsias He } 718433fc58eSAsias He 719dc32bb67SSonny Rao #ifdef CONFIG_COMPAT 720dc32bb67SSonny Rao static long vhost_vsock_dev_compat_ioctl(struct file *f, unsigned int ioctl, 721dc32bb67SSonny Rao unsigned long arg) 722dc32bb67SSonny Rao { 723dc32bb67SSonny Rao return vhost_vsock_dev_ioctl(f, ioctl, (unsigned long)compat_ptr(arg)); 724dc32bb67SSonny Rao } 725dc32bb67SSonny Rao #endif 726dc32bb67SSonny Rao 727433fc58eSAsias He static const struct file_operations vhost_vsock_fops = { 728433fc58eSAsias He .owner = THIS_MODULE, 729433fc58eSAsias He .open = vhost_vsock_dev_open, 730433fc58eSAsias He .release = vhost_vsock_dev_release, 731433fc58eSAsias He .llseek = noop_llseek, 732433fc58eSAsias He .unlocked_ioctl = vhost_vsock_dev_ioctl, 733dc32bb67SSonny Rao #ifdef CONFIG_COMPAT 734dc32bb67SSonny Rao .compat_ioctl = vhost_vsock_dev_compat_ioctl, 735dc32bb67SSonny Rao #endif 736433fc58eSAsias He }; 737433fc58eSAsias He 738433fc58eSAsias He static struct miscdevice vhost_vsock_misc = { 739f4660cc9SStefan Hajnoczi .minor = VHOST_VSOCK_MINOR, 740433fc58eSAsias He .name = "vhost-vsock", 741433fc58eSAsias He .fops = &vhost_vsock_fops, 742433fc58eSAsias He }; 743433fc58eSAsias He 744433fc58eSAsias He static struct virtio_transport vhost_transport = { 745433fc58eSAsias He .transport = { 746433fc58eSAsias He .get_local_cid = vhost_transport_get_local_cid, 747433fc58eSAsias He 748433fc58eSAsias He .init = virtio_transport_do_socket_init, 749433fc58eSAsias He .destruct = virtio_transport_destruct, 750433fc58eSAsias He .release = virtio_transport_release, 751433fc58eSAsias He .connect = virtio_transport_connect, 752433fc58eSAsias He .shutdown = virtio_transport_shutdown, 75316320f36SPeng Tao .cancel_pkt = vhost_transport_cancel_pkt, 754433fc58eSAsias He 755433fc58eSAsias He .dgram_enqueue = virtio_transport_dgram_enqueue, 756433fc58eSAsias He .dgram_dequeue = virtio_transport_dgram_dequeue, 757433fc58eSAsias He .dgram_bind = virtio_transport_dgram_bind, 758433fc58eSAsias He .dgram_allow = virtio_transport_dgram_allow, 759433fc58eSAsias He 760433fc58eSAsias He .stream_enqueue = virtio_transport_stream_enqueue, 761433fc58eSAsias He .stream_dequeue = virtio_transport_stream_dequeue, 762433fc58eSAsias He .stream_has_data = virtio_transport_stream_has_data, 763433fc58eSAsias He .stream_has_space = virtio_transport_stream_has_space, 764433fc58eSAsias He .stream_rcvhiwat = virtio_transport_stream_rcvhiwat, 765433fc58eSAsias He .stream_is_active = virtio_transport_stream_is_active, 766433fc58eSAsias He .stream_allow = virtio_transport_stream_allow, 767433fc58eSAsias He 768433fc58eSAsias He .notify_poll_in = virtio_transport_notify_poll_in, 769433fc58eSAsias He .notify_poll_out = virtio_transport_notify_poll_out, 770433fc58eSAsias He .notify_recv_init = virtio_transport_notify_recv_init, 771433fc58eSAsias He .notify_recv_pre_block = virtio_transport_notify_recv_pre_block, 772433fc58eSAsias He .notify_recv_pre_dequeue = virtio_transport_notify_recv_pre_dequeue, 773433fc58eSAsias He .notify_recv_post_dequeue = virtio_transport_notify_recv_post_dequeue, 774433fc58eSAsias He .notify_send_init = virtio_transport_notify_send_init, 775433fc58eSAsias He .notify_send_pre_block = virtio_transport_notify_send_pre_block, 776433fc58eSAsias He .notify_send_pre_enqueue = virtio_transport_notify_send_pre_enqueue, 777433fc58eSAsias He .notify_send_post_enqueue = virtio_transport_notify_send_post_enqueue, 778433fc58eSAsias He 779433fc58eSAsias He .set_buffer_size = virtio_transport_set_buffer_size, 780433fc58eSAsias He .set_min_buffer_size = virtio_transport_set_min_buffer_size, 781433fc58eSAsias He .set_max_buffer_size = virtio_transport_set_max_buffer_size, 782433fc58eSAsias He .get_buffer_size = virtio_transport_get_buffer_size, 783433fc58eSAsias He .get_min_buffer_size = virtio_transport_get_min_buffer_size, 784433fc58eSAsias He .get_max_buffer_size = virtio_transport_get_max_buffer_size, 785433fc58eSAsias He }, 786433fc58eSAsias He 787433fc58eSAsias He .send_pkt = vhost_transport_send_pkt, 788433fc58eSAsias He }; 789433fc58eSAsias He 790433fc58eSAsias He static int __init vhost_vsock_init(void) 791433fc58eSAsias He { 792433fc58eSAsias He int ret; 793433fc58eSAsias He 794433fc58eSAsias He ret = vsock_core_init(&vhost_transport.transport); 795433fc58eSAsias He if (ret < 0) 796433fc58eSAsias He return ret; 797433fc58eSAsias He return misc_register(&vhost_vsock_misc); 798433fc58eSAsias He }; 799433fc58eSAsias He 800433fc58eSAsias He static void __exit vhost_vsock_exit(void) 801433fc58eSAsias He { 802433fc58eSAsias He misc_deregister(&vhost_vsock_misc); 803433fc58eSAsias He vsock_core_exit(); 804433fc58eSAsias He }; 805433fc58eSAsias He 806433fc58eSAsias He module_init(vhost_vsock_init); 807433fc58eSAsias He module_exit(vhost_vsock_exit); 808433fc58eSAsias He MODULE_LICENSE("GPL v2"); 809433fc58eSAsias He MODULE_AUTHOR("Asias He"); 810433fc58eSAsias He MODULE_DESCRIPTION("vhost transport for vsock "); 811f4660cc9SStefan Hajnoczi MODULE_ALIAS_MISCDEV(VHOST_VSOCK_MINOR); 812f4660cc9SStefan Hajnoczi MODULE_ALIAS("devname:vhost-vsock"); 813