diff options
Diffstat (limited to 'drivers/vhost')
| -rw-r--r-- | drivers/vhost/net.c | 80 | ||||
| -rw-r--r-- | drivers/vhost/scsi.c | 101 | ||||
| -rw-r--r-- | drivers/vhost/test.c | 2 | ||||
| -rw-r--r-- | drivers/vhost/vhost.c | 69 | ||||
| -rw-r--r-- | drivers/vhost/vhost.h | 5 |
5 files changed, 182 insertions, 75 deletions
diff --git a/drivers/vhost/net.c b/drivers/vhost/net.c index 9eda69e40..f744eeb3e 100644 --- a/drivers/vhost/net.c +++ b/drivers/vhost/net.c @@ -287,6 +287,43 @@ static void vhost_zerocopy_callback(struct ubuf_info *ubuf, bool success) rcu_read_unlock_bh(); } +static inline unsigned long busy_clock(void) +{ + return local_clock() >> 10; +} + +static bool vhost_can_busy_poll(struct vhost_dev *dev, + unsigned long endtime) +{ + return likely(!need_resched()) && + likely(!time_after(busy_clock(), endtime)) && + likely(!signal_pending(current)) && + !vhost_has_work(dev); +} + +static int vhost_net_tx_get_vq_desc(struct vhost_net *net, + struct vhost_virtqueue *vq, + struct iovec iov[], unsigned int iov_size, + unsigned int *out_num, unsigned int *in_num) +{ + unsigned long uninitialized_var(endtime); + int r = vhost_get_vq_desc(vq, vq->iov, ARRAY_SIZE(vq->iov), + out_num, in_num, NULL, NULL); + + if (r == vq->num && vq->busyloop_timeout) { + preempt_disable(); + endtime = busy_clock() + vq->busyloop_timeout; + while (vhost_can_busy_poll(vq->dev, endtime) && + vhost_vq_avail_empty(vq->dev, vq)) + cpu_relax_lowlatency(); + preempt_enable(); + r = vhost_get_vq_desc(vq, vq->iov, ARRAY_SIZE(vq->iov), + out_num, in_num, NULL, NULL); + } + + return r; +} + /* Expects to be always run from workqueue - which acts as * read-size critical section for our kind of RCU. */ static void handle_tx(struct vhost_net *net) @@ -331,10 +368,9 @@ static void handle_tx(struct vhost_net *net) % UIO_MAXIOV == nvq->done_idx)) break; - head = vhost_get_vq_desc(vq, vq->iov, - ARRAY_SIZE(vq->iov), - &out, &in, - NULL, NULL); + head = vhost_net_tx_get_vq_desc(net, vq, vq->iov, + ARRAY_SIZE(vq->iov), + &out, &in); /* On error, stop handling until the next kick. */ if (unlikely(head < 0)) break; @@ -435,6 +471,38 @@ static int peek_head_len(struct sock *sk) return len; } +static int vhost_net_rx_peek_head_len(struct vhost_net *net, struct sock *sk) +{ + struct vhost_net_virtqueue *nvq = &net->vqs[VHOST_NET_VQ_TX]; + struct vhost_virtqueue *vq = &nvq->vq; + unsigned long uninitialized_var(endtime); + int len = peek_head_len(sk); + + if (!len && vq->busyloop_timeout) { + /* Both tx vq and rx socket were polled here */ + mutex_lock(&vq->mutex); + vhost_disable_notify(&net->dev, vq); + + preempt_disable(); + endtime = busy_clock() + vq->busyloop_timeout; + + while (vhost_can_busy_poll(&net->dev, endtime) && + skb_queue_empty(&sk->sk_receive_queue) && + vhost_vq_avail_empty(&net->dev, vq)) + cpu_relax_lowlatency(); + + preempt_enable(); + + if (vhost_enable_notify(&net->dev, vq)) + vhost_poll_queue(&vq->poll); + mutex_unlock(&vq->mutex); + + len = peek_head_len(sk); + } + + return len; +} + /* This is a multi-buffer version of vhost_get_desc, that works if * vq has read descriptors only. * @vq - the relevant virtqueue @@ -553,7 +621,7 @@ static void handle_rx(struct vhost_net *net) vq->log : NULL; mergeable = vhost_has_feature(vq, VIRTIO_NET_F_MRG_RXBUF); - while ((sock_len = peek_head_len(sock->sk))) { + while ((sock_len = vhost_net_rx_peek_head_len(net, sock->sk))) { sock_len += sock_hlen; vhost_len = sock_len + vhost_hlen; headcount = get_rx_bufs(vq, vq->heads, vhost_len, @@ -917,7 +985,7 @@ static long vhost_net_set_backend(struct vhost_net *n, unsigned index, int fd) vhost_net_disable_vq(n, vq); vq->private_data = sock; - r = vhost_init_used(vq); + r = vhost_vq_init_access(vq); if (r) goto err_used; r = vhost_net_enable_vq(n, vq); diff --git a/drivers/vhost/scsi.c b/drivers/vhost/scsi.c index 29cfc57d4..0e6fd556c 100644 --- a/drivers/vhost/scsi.c +++ b/drivers/vhost/scsi.c @@ -1274,7 +1274,7 @@ vhost_scsi_set_endpoint(struct vhost_scsi *vs, vq = &vs->vqs[i].vq; mutex_lock(&vq->mutex); vq->private_data = vs_tpg; - vhost_init_used(vq); + vhost_vq_init_access(vq); mutex_unlock(&vq->mutex); } ret = 0; @@ -1664,8 +1664,7 @@ static void vhost_scsi_port_unlink(struct se_portal_group *se_tpg, mutex_unlock(&vhost_scsi_mutex); } -static void vhost_scsi_free_cmd_map_res(struct vhost_scsi_nexus *nexus, - struct se_session *se_sess) +static void vhost_scsi_free_cmd_map_res(struct se_session *se_sess) { struct vhost_scsi_cmd *tv_cmd; unsigned int i; @@ -1721,98 +1720,82 @@ static struct configfs_attribute *vhost_scsi_tpg_attrib_attrs[] = { NULL, }; -static int vhost_scsi_make_nexus(struct vhost_scsi_tpg *tpg, - const char *name) +static int vhost_scsi_nexus_cb(struct se_portal_group *se_tpg, + struct se_session *se_sess, void *p) { - struct se_portal_group *se_tpg; - struct se_session *se_sess; - struct vhost_scsi_nexus *tv_nexus; struct vhost_scsi_cmd *tv_cmd; unsigned int i; - mutex_lock(&tpg->tv_tpg_mutex); - if (tpg->tpg_nexus) { - mutex_unlock(&tpg->tv_tpg_mutex); - pr_debug("tpg->tpg_nexus already exists\n"); - return -EEXIST; - } - se_tpg = &tpg->se_tpg; - - tv_nexus = kzalloc(sizeof(struct vhost_scsi_nexus), GFP_KERNEL); - if (!tv_nexus) { - mutex_unlock(&tpg->tv_tpg_mutex); - pr_err("Unable to allocate struct vhost_scsi_nexus\n"); - return -ENOMEM; - } - /* - * Initialize the struct se_session pointer and setup tagpool - * for struct vhost_scsi_cmd descriptors - */ - tv_nexus->tvn_se_sess = transport_init_session_tags( - VHOST_SCSI_DEFAULT_TAGS, - sizeof(struct vhost_scsi_cmd), - TARGET_PROT_DIN_PASS | TARGET_PROT_DOUT_PASS); - if (IS_ERR(tv_nexus->tvn_se_sess)) { - mutex_unlock(&tpg->tv_tpg_mutex); - kfree(tv_nexus); - return -ENOMEM; - } - se_sess = tv_nexus->tvn_se_sess; for (i = 0; i < VHOST_SCSI_DEFAULT_TAGS; i++) { tv_cmd = &((struct vhost_scsi_cmd *)se_sess->sess_cmd_map)[i]; tv_cmd->tvc_sgl = kzalloc(sizeof(struct scatterlist) * VHOST_SCSI_PREALLOC_SGLS, GFP_KERNEL); if (!tv_cmd->tvc_sgl) { - mutex_unlock(&tpg->tv_tpg_mutex); pr_err("Unable to allocate tv_cmd->tvc_sgl\n"); goto out; } tv_cmd->tvc_upages = kzalloc(sizeof(struct page *) * - VHOST_SCSI_PREALLOC_UPAGES, GFP_KERNEL); + VHOST_SCSI_PREALLOC_UPAGES, GFP_KERNEL); if (!tv_cmd->tvc_upages) { - mutex_unlock(&tpg->tv_tpg_mutex); pr_err("Unable to allocate tv_cmd->tvc_upages\n"); goto out; } tv_cmd->tvc_prot_sgl = kzalloc(sizeof(struct scatterlist) * - VHOST_SCSI_PREALLOC_PROT_SGLS, GFP_KERNEL); + VHOST_SCSI_PREALLOC_PROT_SGLS, GFP_KERNEL); if (!tv_cmd->tvc_prot_sgl) { - mutex_unlock(&tpg->tv_tpg_mutex); pr_err("Unable to allocate tv_cmd->tvc_prot_sgl\n"); goto out; } } + return 0; +out: + vhost_scsi_free_cmd_map_res(se_sess); + return -ENOMEM; +} + +static int vhost_scsi_make_nexus(struct vhost_scsi_tpg *tpg, + const char *name) +{ + struct se_portal_group *se_tpg; + struct vhost_scsi_nexus *tv_nexus; + + mutex_lock(&tpg->tv_tpg_mutex); + if (tpg->tpg_nexus) { + mutex_unlock(&tpg->tv_tpg_mutex); + pr_debug("tpg->tpg_nexus already exists\n"); + return -EEXIST; + } + se_tpg = &tpg->se_tpg; + + tv_nexus = kzalloc(sizeof(struct vhost_scsi_nexus), GFP_KERNEL); + if (!tv_nexus) { + mutex_unlock(&tpg->tv_tpg_mutex); + pr_err("Unable to allocate struct vhost_scsi_nexus\n"); + return -ENOMEM; + } /* * Since we are running in 'demo mode' this call with generate a * struct se_node_acl for the vhost_scsi struct se_portal_group with * the SCSI Initiator port name of the passed configfs group 'name'. */ - tv_nexus->tvn_se_sess->se_node_acl = core_tpg_check_initiator_node_acl( - se_tpg, (unsigned char *)name); - if (!tv_nexus->tvn_se_sess->se_node_acl) { + tv_nexus->tvn_se_sess = target_alloc_session(&tpg->se_tpg, + VHOST_SCSI_DEFAULT_TAGS, + sizeof(struct vhost_scsi_cmd), + TARGET_PROT_DIN_PASS | TARGET_PROT_DOUT_PASS, + (unsigned char *)name, tv_nexus, + vhost_scsi_nexus_cb); + if (IS_ERR(tv_nexus->tvn_se_sess)) { mutex_unlock(&tpg->tv_tpg_mutex); - pr_debug("core_tpg_check_initiator_node_acl() failed" - " for %s\n", name); - goto out; + kfree(tv_nexus); + return -ENOMEM; } - /* - * Now register the TCM vhost virtual I_T Nexus as active. - */ - transport_register_session(se_tpg, tv_nexus->tvn_se_sess->se_node_acl, - tv_nexus->tvn_se_sess, tv_nexus); tpg->tpg_nexus = tv_nexus; mutex_unlock(&tpg->tv_tpg_mutex); return 0; - -out: - vhost_scsi_free_cmd_map_res(tv_nexus, se_sess); - transport_free_session(se_sess); - kfree(tv_nexus); - return -ENOMEM; } static int vhost_scsi_drop_nexus(struct vhost_scsi_tpg *tpg) @@ -1853,7 +1836,7 @@ static int vhost_scsi_drop_nexus(struct vhost_scsi_tpg *tpg) " %s Initiator Port: %s\n", vhost_scsi_dump_proto_id(tpg->tport), tv_nexus->tvn_se_sess->se_node_acl->initiatorname); - vhost_scsi_free_cmd_map_res(tv_nexus, se_sess); + vhost_scsi_free_cmd_map_res(se_sess); /* * Release the SCSI I_T Nexus to the emulated vhost Target Port */ diff --git a/drivers/vhost/test.c b/drivers/vhost/test.c index f2882ac98..388eec4e1 100644 --- a/drivers/vhost/test.c +++ b/drivers/vhost/test.c @@ -196,7 +196,7 @@ static long vhost_test_run(struct vhost_test *n, int test) oldpriv = vq->private_data; vq->private_data = priv; - r = vhost_init_used(&n->vqs[index]); + r = vhost_vq_init_access(&n->vqs[index]); mutex_unlock(&vq->mutex); diff --git a/drivers/vhost/vhost.c b/drivers/vhost/vhost.c index 236553e81..669fef1e2 100644 --- a/drivers/vhost/vhost.c +++ b/drivers/vhost/vhost.c @@ -43,11 +43,21 @@ enum { #define vhost_avail_event(vq) ((__virtio16 __user *)&vq->used->ring[vq->num]) #ifdef CONFIG_VHOST_CROSS_ENDIAN_LEGACY -static void vhost_vq_reset_user_be(struct vhost_virtqueue *vq) +static void vhost_disable_cross_endian(struct vhost_virtqueue *vq) { vq->user_be = !virtio_legacy_is_little_endian(); } +static void vhost_enable_cross_endian_big(struct vhost_virtqueue *vq) +{ + vq->user_be = true; +} + +static void vhost_enable_cross_endian_little(struct vhost_virtqueue *vq) +{ + vq->user_be = false; +} + static long vhost_set_vring_endian(struct vhost_virtqueue *vq, int __user *argp) { struct vhost_vring_state s; @@ -62,7 +72,10 @@ static long vhost_set_vring_endian(struct vhost_virtqueue *vq, int __user *argp) s.num != VHOST_VRING_BIG_ENDIAN) return -EINVAL; - vq->user_be = s.num; + if (s.num == VHOST_VRING_BIG_ENDIAN) + vhost_enable_cross_endian_big(vq); + else + vhost_enable_cross_endian_little(vq); return 0; } @@ -91,7 +104,7 @@ static void vhost_init_is_le(struct vhost_virtqueue *vq) vq->is_le = vhost_has_feature(vq, VIRTIO_F_VERSION_1) || !vq->user_be; } #else -static void vhost_vq_reset_user_be(struct vhost_virtqueue *vq) +static void vhost_disable_cross_endian(struct vhost_virtqueue *vq) { } @@ -113,6 +126,11 @@ static void vhost_init_is_le(struct vhost_virtqueue *vq) } #endif /* CONFIG_VHOST_CROSS_ENDIAN_LEGACY */ +static void vhost_reset_is_le(struct vhost_virtqueue *vq) +{ + vq->is_le = virtio_legacy_is_little_endian(); +} + static void vhost_poll_func(struct file *file, wait_queue_head_t *wqh, poll_table *pt) { @@ -245,6 +263,13 @@ void vhost_work_queue(struct vhost_dev *dev, struct vhost_work *work) } EXPORT_SYMBOL_GPL(vhost_work_queue); +/* A lockless hint for busy polling code to exit the loop */ +bool vhost_has_work(struct vhost_dev *dev) +{ + return !list_empty(&dev->work_list); +} +EXPORT_SYMBOL_GPL(vhost_has_work); + void vhost_poll_queue(struct vhost_poll *poll) { vhost_work_queue(poll->dev, &poll->work); @@ -276,8 +301,9 @@ static void vhost_vq_reset(struct vhost_dev *dev, vq->call = NULL; vq->log_ctx = NULL; vq->memory = NULL; - vq->is_le = virtio_legacy_is_little_endian(); - vhost_vq_reset_user_be(vq); + vhost_reset_is_le(vq); + vhost_disable_cross_endian(vq); + vq->busyloop_timeout = 0; } static int vhost_worker(void *data) @@ -912,6 +938,19 @@ long vhost_vring_ioctl(struct vhost_dev *d, int ioctl, void __user *argp) case VHOST_GET_VRING_ENDIAN: r = vhost_get_vring_endian(vq, idx, argp); break; + case VHOST_SET_VRING_BUSYLOOP_TIMEOUT: + if (copy_from_user(&s, argp, sizeof(s))) { + r = -EFAULT; + break; + } + vq->busyloop_timeout = s.num; + break; + case VHOST_GET_VRING_BUSYLOOP_TIMEOUT: + s.index = idx; + s.num = vq->busyloop_timeout; + if (copy_to_user(argp, &s, sizeof(s))) + r = -EFAULT; + break; default: r = -ENOIOCTLCMD; } @@ -1152,14 +1191,14 @@ static int vhost_update_avail_event(struct vhost_virtqueue *vq, u16 avail_event) return 0; } -int vhost_init_used(struct vhost_virtqueue *vq) +int vhost_vq_init_access(struct vhost_virtqueue *vq) { __virtio16 last_used_idx; int r; bool is_le = vq->is_le; if (!vq->private_data) { - vq->is_le = virtio_legacy_is_little_endian(); + vhost_reset_is_le(vq); return 0; } @@ -1182,7 +1221,7 @@ err: vq->is_le = is_le; return r; } -EXPORT_SYMBOL_GPL(vhost_init_used); +EXPORT_SYMBOL_GPL(vhost_vq_init_access); static int translate_desc(struct vhost_virtqueue *vq, u64 addr, u32 len, struct iovec iov[], int iov_size) @@ -1633,6 +1672,20 @@ void vhost_add_used_and_signal_n(struct vhost_dev *dev, } EXPORT_SYMBOL_GPL(vhost_add_used_and_signal_n); +/* return true if we're sure that avaiable ring is empty */ +bool vhost_vq_avail_empty(struct vhost_dev *dev, struct vhost_virtqueue *vq) +{ + __virtio16 avail_idx; + int r; + + r = __get_user(avail_idx, &vq->avail->idx); + if (r) + return false; + + return vhost16_to_cpu(vq, avail_idx) == vq->avail_idx; +} +EXPORT_SYMBOL_GPL(vhost_vq_avail_empty); + /* OK, now we need to know about added descriptors. */ bool vhost_enable_notify(struct vhost_dev *dev, struct vhost_virtqueue *vq) { diff --git a/drivers/vhost/vhost.h b/drivers/vhost/vhost.h index d3f767448..d36d8beb3 100644 --- a/drivers/vhost/vhost.h +++ b/drivers/vhost/vhost.h @@ -37,6 +37,7 @@ struct vhost_poll { void vhost_work_init(struct vhost_work *work, vhost_work_fn_t fn); void vhost_work_queue(struct vhost_dev *dev, struct vhost_work *work); +bool vhost_has_work(struct vhost_dev *dev); void vhost_poll_init(struct vhost_poll *poll, vhost_work_fn_t fn, unsigned long mask, struct vhost_dev *dev); @@ -114,6 +115,7 @@ struct vhost_virtqueue { /* Ring endianness requested by userspace for cross-endian support. */ bool user_be; #endif + u32 busyloop_timeout; }; struct vhost_dev { @@ -148,7 +150,7 @@ int vhost_get_vq_desc(struct vhost_virtqueue *, struct vhost_log *log, unsigned int *log_num); void vhost_discard_vq_desc(struct vhost_virtqueue *, int n); -int vhost_init_used(struct vhost_virtqueue *); +int vhost_vq_init_access(struct vhost_virtqueue *); int vhost_add_used(struct vhost_virtqueue *, unsigned int head, int len); int vhost_add_used_n(struct vhost_virtqueue *, struct vring_used_elem *heads, unsigned count); @@ -158,6 +160,7 @@ void vhost_add_used_and_signal_n(struct vhost_dev *, struct vhost_virtqueue *, struct vring_used_elem *heads, unsigned count); void vhost_signal(struct vhost_dev *, struct vhost_virtqueue *); void vhost_disable_notify(struct vhost_dev *, struct vhost_virtqueue *); +bool vhost_vq_avail_empty(struct vhost_dev *, struct vhost_virtqueue *); bool vhost_enable_notify(struct vhost_dev *, struct vhost_virtqueue *); int vhost_log_write(struct vhost_virtqueue *vq, struct vhost_log *log, |