diff options
Diffstat (limited to 'drivers/vhost')
| -rw-r--r-- | drivers/vhost/Kconfig | 30 | ||||
| -rw-r--r-- | drivers/vhost/Kconfig.tcm | 6 | ||||
| -rw-r--r-- | drivers/vhost/Makefile | 8 | ||||
| -rw-r--r-- | drivers/vhost/net.c | 549 | ||||
| -rw-r--r-- | drivers/vhost/scsi.c | 2367 | ||||
| -rw-r--r-- | drivers/vhost/tcm_vhost.c | 1593 | ||||
| -rw-r--r-- | drivers/vhost/tcm_vhost.h | 111 | ||||
| -rw-r--r-- | drivers/vhost/test.c | 67 | ||||
| -rw-r--r-- | drivers/vhost/vhost.c | 383 | ||||
| -rw-r--r-- | drivers/vhost/vhost.h | 76 | ||||
| -rw-r--r-- | drivers/vhost/vringh.c | 1010 |
11 files changed, 3999 insertions, 2201 deletions
diff --git a/drivers/vhost/Kconfig b/drivers/vhost/Kconfig index 202bba6c997..017a1e8a8f6 100644 --- a/drivers/vhost/Kconfig +++ b/drivers/vhost/Kconfig @@ -1,6 +1,8 @@ config VHOST_NET - tristate "Host kernel accelerator for virtio net (EXPERIMENTAL)" - depends on NET && EVENTFD && (TUN || !TUN) && (MACVTAP || !MACVTAP) && EXPERIMENTAL + tristate "Host kernel accelerator for virtio net" + depends on NET && EVENTFD && (TUN || !TUN) && (MACVTAP || !MACVTAP) + select VHOST + select VHOST_RING ---help--- This kernel module can be loaded in host kernel to accelerate guest networking with virtio_net. Not to be confused with virtio_net @@ -9,6 +11,24 @@ config VHOST_NET To compile this driver as a module, choose M here: the module will be called vhost_net. -if STAGING -source "drivers/vhost/Kconfig.tcm" -endif +config VHOST_SCSI + tristate "VHOST_SCSI TCM fabric driver" + depends on TARGET_CORE && EVENTFD && m + select VHOST + select VHOST_RING + default n + ---help--- + Say M here to enable the vhost_scsi TCM fabric module + for use with virtio-scsi guests + +config VHOST_RING + tristate + ---help--- + This option is selected by any driver which needs to access + the host side of a virtio ring. + +config VHOST + tristate + ---help--- + This option is selected by any driver which needs to access + the core of vhost. diff --git a/drivers/vhost/Kconfig.tcm b/drivers/vhost/Kconfig.tcm deleted file mode 100644 index a9c6f76e320..00000000000 --- a/drivers/vhost/Kconfig.tcm +++ /dev/null @@ -1,6 +0,0 @@ -config TCM_VHOST - tristate "TCM_VHOST fabric module (EXPERIMENTAL)" - depends on TARGET_CORE && EVENTFD && EXPERIMENTAL && m - default n - ---help--- - Say M here to enable the TCM_VHOST fabric module for use with virtio-scsi guests diff --git a/drivers/vhost/Makefile b/drivers/vhost/Makefile index a27b053bc9a..e0441c34db1 100644 --- a/drivers/vhost/Makefile +++ b/drivers/vhost/Makefile @@ -1,4 +1,8 @@ obj-$(CONFIG_VHOST_NET) += vhost_net.o -vhost_net-y := vhost.o net.o +vhost_net-y := net.o -obj-$(CONFIG_TCM_VHOST) += tcm_vhost.o +obj-$(CONFIG_VHOST_SCSI) += vhost_scsi.o +vhost_scsi-y := scsi.o + +obj-$(CONFIG_VHOST_RING) += vringh.o +obj-$(CONFIG_VHOST) += vhost.o diff --git a/drivers/vhost/net.c b/drivers/vhost/net.c index ebd08b21b23..8dae2f724a3 100644 --- a/drivers/vhost/net.c +++ b/drivers/vhost/net.c @@ -15,9 +15,9 @@ #include <linux/moduleparam.h> #include <linux/mutex.h> #include <linux/workqueue.h> -#include <linux/rcupdate.h> #include <linux/file.h> #include <linux/slab.h> +#include <linux/vmalloc.h> #include <linux/net.h> #include <linux/if_packet.h> @@ -59,25 +59,52 @@ MODULE_PARM_DESC(experimental_zcopytx, "Enable Zero Copy TX;" #define VHOST_DMA_IS_DONE(len) ((len) >= VHOST_DMA_DONE_LEN) enum { + VHOST_NET_FEATURES = VHOST_FEATURES | + (1ULL << VHOST_NET_F_VIRTIO_NET_HDR) | + (1ULL << VIRTIO_NET_F_MRG_RXBUF), +}; + +enum { VHOST_NET_VQ_RX = 0, VHOST_NET_VQ_TX = 1, VHOST_NET_VQ_MAX = 2, }; -enum vhost_net_poll_state { - VHOST_NET_POLL_DISABLED = 0, - VHOST_NET_POLL_STARTED = 1, - VHOST_NET_POLL_STOPPED = 2, +struct vhost_net_ubuf_ref { + /* refcount follows semantics similar to kref: + * 0: object is released + * 1: no outstanding ubufs + * >1: outstanding ubufs + */ + atomic_t refcount; + wait_queue_head_t wait; + struct vhost_virtqueue *vq; +}; + +struct vhost_net_virtqueue { + struct vhost_virtqueue vq; + /* hdr is used to store the virtio header. + * Since each iovec has >= 1 byte length, we never need more than + * header length entries to store the header. */ + struct iovec hdr[sizeof(struct virtio_net_hdr_mrg_rxbuf)]; + size_t vhost_hlen; + size_t sock_hlen; + /* vhost zerocopy support fields below: */ + /* last used idx for outstanding DMA zerocopy buffers */ + int upend_idx; + /* first used idx for DMA done zerocopy buffers */ + int done_idx; + /* an array of userspace buffers info */ + struct ubuf_info *ubuf_info; + /* Reference counting for outstanding ubufs. + * Protected by vq mutex. Writers must also take device mutex. */ + struct vhost_net_ubuf_ref *ubufs; }; struct vhost_net { struct vhost_dev dev; - struct vhost_virtqueue vqs[VHOST_NET_VQ_MAX]; + struct vhost_net_virtqueue vqs[VHOST_NET_VQ_MAX]; struct vhost_poll poll[VHOST_NET_VQ_MAX]; - /* Tells us whether we are polling a socket for TX. - * We only do this when socket buffer fills up. - * Protected by tx vq lock. */ - enum vhost_net_poll_state tx_poll_state; /* Number of TX recently submitted. * Protected by tx vq lock. */ unsigned tx_packets; @@ -88,6 +115,96 @@ struct vhost_net { bool tx_flush; }; +static unsigned vhost_net_zcopy_mask __read_mostly; + +static void vhost_net_enable_zcopy(int vq) +{ + vhost_net_zcopy_mask |= 0x1 << vq; +} + +static struct vhost_net_ubuf_ref * +vhost_net_ubuf_alloc(struct vhost_virtqueue *vq, bool zcopy) +{ + struct vhost_net_ubuf_ref *ubufs; + /* No zero copy backend? Nothing to count. */ + if (!zcopy) + return NULL; + ubufs = kmalloc(sizeof(*ubufs), GFP_KERNEL); + if (!ubufs) + return ERR_PTR(-ENOMEM); + atomic_set(&ubufs->refcount, 1); + init_waitqueue_head(&ubufs->wait); + ubufs->vq = vq; + return ubufs; +} + +static int vhost_net_ubuf_put(struct vhost_net_ubuf_ref *ubufs) +{ + int r = atomic_sub_return(1, &ubufs->refcount); + if (unlikely(!r)) + wake_up(&ubufs->wait); + return r; +} + +static void vhost_net_ubuf_put_and_wait(struct vhost_net_ubuf_ref *ubufs) +{ + vhost_net_ubuf_put(ubufs); + wait_event(ubufs->wait, !atomic_read(&ubufs->refcount)); +} + +static void vhost_net_ubuf_put_wait_and_free(struct vhost_net_ubuf_ref *ubufs) +{ + vhost_net_ubuf_put_and_wait(ubufs); + kfree(ubufs); +} + +static void vhost_net_clear_ubuf_info(struct vhost_net *n) +{ + int i; + + for (i = 0; i < VHOST_NET_VQ_MAX; ++i) { + kfree(n->vqs[i].ubuf_info); + n->vqs[i].ubuf_info = NULL; + } +} + +static int vhost_net_set_ubuf_info(struct vhost_net *n) +{ + bool zcopy; + int i; + + for (i = 0; i < VHOST_NET_VQ_MAX; ++i) { + zcopy = vhost_net_zcopy_mask & (0x1 << i); + if (!zcopy) + continue; + n->vqs[i].ubuf_info = kmalloc(sizeof(*n->vqs[i].ubuf_info) * + UIO_MAXIOV, GFP_KERNEL); + if (!n->vqs[i].ubuf_info) + goto err; + } + return 0; + +err: + vhost_net_clear_ubuf_info(n); + return -ENOMEM; +} + +static void vhost_net_vq_reset(struct vhost_net *n) +{ + int i; + + vhost_net_clear_ubuf_info(n); + + for (i = 0; i < VHOST_NET_VQ_MAX; i++) { + n->vqs[i].done_idx = 0; + n->vqs[i].upend_idx = 0; + n->vqs[i].ubufs = NULL; + n->vqs[i].vhost_hlen = 0; + n->vqs[i].sock_hlen = 0; + } + +} + static void vhost_net_tx_packet(struct vhost_net *net) { ++net->tx_packets; @@ -155,78 +272,69 @@ static void copy_iovec_hdr(const struct iovec *from, struct iovec *to, } } -/* Caller must have TX VQ lock */ -static void tx_poll_stop(struct vhost_net *net) -{ - if (likely(net->tx_poll_state != VHOST_NET_POLL_STARTED)) - return; - vhost_poll_stop(net->poll + VHOST_NET_VQ_TX); - net->tx_poll_state = VHOST_NET_POLL_STOPPED; -} - -/* Caller must have TX VQ lock */ -static void tx_poll_start(struct vhost_net *net, struct socket *sock) -{ - if (unlikely(net->tx_poll_state != VHOST_NET_POLL_STOPPED)) - return; - vhost_poll_start(net->poll + VHOST_NET_VQ_TX, sock->file); - net->tx_poll_state = VHOST_NET_POLL_STARTED; -} - /* In case of DMA done not in order in lower device driver for some reason. * upend_idx is used to track end of used idx, done_idx is used to track head * of used idx. Once lower device DMA done contiguously, we will signal KVM * guest used idx. */ -static int vhost_zerocopy_signal_used(struct vhost_net *net, - struct vhost_virtqueue *vq) +static void vhost_zerocopy_signal_used(struct vhost_net *net, + struct vhost_virtqueue *vq) { - int i; + struct vhost_net_virtqueue *nvq = + container_of(vq, struct vhost_net_virtqueue, vq); + int i, add; int j = 0; - for (i = vq->done_idx; i != vq->upend_idx; i = (i + 1) % UIO_MAXIOV) { + for (i = nvq->done_idx; i != nvq->upend_idx; i = (i + 1) % UIO_MAXIOV) { if (vq->heads[i].len == VHOST_DMA_FAILED_LEN) vhost_net_tx_err(net); if (VHOST_DMA_IS_DONE(vq->heads[i].len)) { vq->heads[i].len = VHOST_DMA_CLEAR_LEN; - vhost_add_used_and_signal(vq->dev, vq, - vq->heads[i].id, 0); ++j; } else break; } - if (j) - vq->done_idx = i; - return j; + while (j) { + add = min(UIO_MAXIOV - nvq->done_idx, j); + vhost_add_used_and_signal_n(vq->dev, vq, + &vq->heads[nvq->done_idx], add); + nvq->done_idx = (nvq->done_idx + add) % UIO_MAXIOV; + j -= add; + } } static void vhost_zerocopy_callback(struct ubuf_info *ubuf, bool success) { - struct vhost_ubuf_ref *ubufs = ubuf->ctx; + struct vhost_net_ubuf_ref *ubufs = ubuf->ctx; struct vhost_virtqueue *vq = ubufs->vq; - int cnt = atomic_read(&ubufs->kref.refcount); + int cnt; + + rcu_read_lock_bh(); + + /* set len to mark this desc buffers done DMA */ + vq->heads[ubuf->desc].len = success ? + VHOST_DMA_DONE_LEN : VHOST_DMA_FAILED_LEN; + cnt = vhost_net_ubuf_put(ubufs); /* * Trigger polling thread if guest stopped submitting new buffers: - * in this case, the refcount after decrement will eventually reach 1 - * so here it is 2. + * in this case, the refcount after decrement will eventually reach 1. * We also trigger polling periodically after each 16 packets * (the value 16 here is more or less arbitrary, it's tuned to trigger * less than 10% of times). */ - if (cnt <= 2 || !(cnt % 16)) + if (cnt <= 1 || !(cnt % 16)) vhost_poll_queue(&vq->poll); - /* set len to mark this desc buffers done DMA */ - vq->heads[ubuf->desc].len = success ? - VHOST_DMA_DONE_LEN : VHOST_DMA_FAILED_LEN; - vhost_ubuf_put(ubufs); + + rcu_read_unlock_bh(); } /* 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) { - struct vhost_virtqueue *vq = &net->dev.vqs[VHOST_NET_VQ_TX]; + struct vhost_net_virtqueue *nvq = &net->vqs[VHOST_NET_VQ_TX]; + struct vhost_virtqueue *vq = &nvq->vq; unsigned out, in, s; int head; struct msghdr msg = { @@ -238,39 +346,35 @@ static void handle_tx(struct vhost_net *net) .msg_flags = MSG_DONTWAIT, }; size_t len, total_len = 0; - int err, wmem; + int err; size_t hdr_size; struct socket *sock; - struct vhost_ubuf_ref *uninitialized_var(ubufs); + struct vhost_net_ubuf_ref *uninitialized_var(ubufs); bool zcopy, zcopy_used; - /* TODO: check that we are running from vhost_worker? */ - sock = rcu_dereference_check(vq->private_data, 1); + mutex_lock(&vq->mutex); + sock = vq->private_data; if (!sock) - return; - - wmem = atomic_read(&sock->sk->sk_wmem_alloc); - if (wmem >= sock->sk->sk_sndbuf) { - mutex_lock(&vq->mutex); - tx_poll_start(net, sock); - mutex_unlock(&vq->mutex); - return; - } + goto out; - mutex_lock(&vq->mutex); vhost_disable_notify(&net->dev, vq); - if (wmem < sock->sk->sk_sndbuf / 2) - tx_poll_stop(net); - hdr_size = vq->vhost_hlen; - zcopy = vq->ubufs; + hdr_size = nvq->vhost_hlen; + zcopy = nvq->ubufs; for (;;) { /* Release DMAs done buffers first */ if (zcopy) vhost_zerocopy_signal_used(net, vq); - head = vhost_get_vq_desc(&net->dev, vq, vq->iov, + /* If more outstanding DMAs, queue the work. + * Handle upend_idx wrap around + */ + if (unlikely((nvq->upend_idx + vq->num - VHOST_MAX_PEND) + % UIO_MAXIOV == nvq->done_idx)) + break; + + head = vhost_get_vq_desc(vq, vq->iov, ARRAY_SIZE(vq->iov), &out, &in, NULL, NULL); @@ -279,25 +383,6 @@ static void handle_tx(struct vhost_net *net) break; /* Nothing new? Wait for eventfd to tell us they refilled. */ if (head == vq->num) { - int num_pends; - - wmem = atomic_read(&sock->sk->sk_wmem_alloc); - if (wmem >= sock->sk->sk_sndbuf * 3 / 4) { - tx_poll_start(net, sock); - set_bit(SOCK_ASYNC_NOSPACE, &sock->flags); - break; - } - /* If more outstanding DMAs, queue the work. - * Handle upend_idx wrap around - */ - num_pends = likely(vq->upend_idx >= vq->done_idx) ? - (vq->upend_idx - vq->done_idx) : - (vq->upend_idx + UIO_MAXIOV - vq->done_idx); - if (unlikely(num_pends > VHOST_MAX_PEND)) { - tx_poll_start(net, sock); - set_bit(SOCK_ASYNC_NOSPACE, &sock->flags); - break; - } if (unlikely(vhost_enable_notify(&net->dev, vq))) { vhost_disable_notify(&net->dev, vq); continue; @@ -310,57 +395,50 @@ static void handle_tx(struct vhost_net *net) break; } /* Skip header. TODO: support TSO. */ - s = move_iovec_hdr(vq->iov, vq->hdr, hdr_size, out); + s = move_iovec_hdr(vq->iov, nvq->hdr, hdr_size, out); msg.msg_iovlen = out; len = iov_length(vq->iov, out); /* Sanity check */ if (!len) { vq_err(vq, "Unexpected header len for TX: " "%zd expected %zd\n", - iov_length(vq->hdr, s), hdr_size); + iov_length(nvq->hdr, s), hdr_size); break; } - zcopy_used = zcopy && (len >= VHOST_GOODCOPY_LEN || - vq->upend_idx != vq->done_idx); + + zcopy_used = zcopy && len >= VHOST_GOODCOPY_LEN + && (nvq->upend_idx + 1) % UIO_MAXIOV != + nvq->done_idx + && vhost_net_tx_select_zcopy(net); /* use msg_control to pass vhost zerocopy ubuf info to skb */ if (zcopy_used) { - vq->heads[vq->upend_idx].id = head; - if (!vhost_net_tx_select_zcopy(net) || - len < VHOST_GOODCOPY_LEN) { - /* copy don't need to wait for DMA done */ - vq->heads[vq->upend_idx].len = - VHOST_DMA_DONE_LEN; - msg.msg_control = NULL; - msg.msg_controllen = 0; - ubufs = NULL; - } else { - struct ubuf_info *ubuf = &vq->ubuf_info[head]; - - vq->heads[vq->upend_idx].len = - VHOST_DMA_IN_PROGRESS; - ubuf->callback = vhost_zerocopy_callback; - ubuf->ctx = vq->ubufs; - ubuf->desc = vq->upend_idx; - msg.msg_control = ubuf; - msg.msg_controllen = sizeof(ubuf); - ubufs = vq->ubufs; - kref_get(&ubufs->kref); - } - vq->upend_idx = (vq->upend_idx + 1) % UIO_MAXIOV; + struct ubuf_info *ubuf; + ubuf = nvq->ubuf_info + nvq->upend_idx; + + vq->heads[nvq->upend_idx].id = head; + vq->heads[nvq->upend_idx].len = VHOST_DMA_IN_PROGRESS; + ubuf->callback = vhost_zerocopy_callback; + ubuf->ctx = nvq->ubufs; + ubuf->desc = nvq->upend_idx; + msg.msg_control = ubuf; + msg.msg_controllen = sizeof(ubuf); + ubufs = nvq->ubufs; + atomic_inc(&ubufs->refcount); + nvq->upend_idx = (nvq->upend_idx + 1) % UIO_MAXIOV; + } else { + msg.msg_control = NULL; + ubufs = NULL; } /* TODO: Check specific error and bomb out unless ENOBUFS? */ err = sock->ops->sendmsg(NULL, sock, &msg, len); if (unlikely(err < 0)) { if (zcopy_used) { - if (ubufs) - vhost_ubuf_put(ubufs); - vq->upend_idx = ((unsigned)vq->upend_idx - 1) % - UIO_MAXIOV; + vhost_net_ubuf_put(ubufs); + nvq->upend_idx = ((unsigned)nvq->upend_idx - 1) + % UIO_MAXIOV; } vhost_discard_vq_desc(vq, 1); - if (err == -EAGAIN || err == -ENOBUFS) - tx_poll_start(net, sock); break; } if (err != len) @@ -377,7 +455,7 @@ static void handle_tx(struct vhost_net *net) break; } } - +out: mutex_unlock(&vq->mutex); } @@ -428,9 +506,13 @@ static int get_rx_bufs(struct vhost_virtqueue *vq, r = -ENOBUFS; goto err; } - d = vhost_get_vq_desc(vq->dev, vq, vq->iov + seg, + r = vhost_get_vq_desc(vq, vq->iov + seg, ARRAY_SIZE(vq->iov) - seg, &out, &in, log, log_num); + if (unlikely(r < 0)) + goto err; + + d = r; if (d == vq->num) { r = 0; goto err; @@ -455,6 +537,12 @@ static int get_rx_bufs(struct vhost_virtqueue *vq, *iovcount = seg; if (unlikely(log)) *log_num = nlogs; + + /* Detect overrun */ + if (unlikely(datalen > 0)) { + r = UIO_MAXIOV + 1; + goto err; + } return headcount; err: vhost_discard_vq_desc(vq, headcount); @@ -465,7 +553,8 @@ err: * read-size critical section for our kind of RCU. */ static void handle_rx(struct vhost_net *net) { - struct vhost_virtqueue *vq = &net->dev.vqs[VHOST_NET_VQ_RX]; + struct vhost_net_virtqueue *nvq = &net->vqs[VHOST_NET_VQ_RX]; + struct vhost_virtqueue *vq = &nvq->vq; unsigned uninitialized_var(in), log; struct vhost_log *vq_log; struct msghdr msg = { @@ -485,20 +574,20 @@ static void handle_rx(struct vhost_net *net) s16 headcount; size_t vhost_hlen, sock_hlen; size_t vhost_len, sock_len; - /* TODO: check that we are running from vhost_worker? */ - struct socket *sock = rcu_dereference_check(vq->private_data, 1); - - if (!sock) - return; + struct socket *sock; mutex_lock(&vq->mutex); + sock = vq->private_data; + if (!sock) + goto out; vhost_disable_notify(&net->dev, vq); - vhost_hlen = vq->vhost_hlen; - sock_hlen = vq->sock_hlen; - vq_log = unlikely(vhost_has_feature(&net->dev, VHOST_F_LOG_ALL)) ? + vhost_hlen = nvq->vhost_hlen; + sock_hlen = nvq->sock_hlen; + + vq_log = unlikely(vhost_has_feature(vq, VHOST_F_LOG_ALL)) ? vq->log : NULL; - mergeable = vhost_has_feature(&net->dev, VIRTIO_NET_F_MRG_RXBUF); + mergeable = vhost_has_feature(vq, VIRTIO_NET_F_MRG_RXBUF); while ((sock_len = peek_head_len(sock->sk))) { sock_len += sock_hlen; @@ -509,6 +598,14 @@ static void handle_rx(struct vhost_net *net) /* On error, stop handling until the next kick. */ if (unlikely(headcount < 0)) break; + /* On overrun, truncate and discard */ + if (unlikely(headcount > UIO_MAXIOV)) { + msg.msg_iovlen = 1; + err = sock->ops->recvmsg(NULL, sock, &msg, + 1, MSG_DONTWAIT | MSG_TRUNC); + pr_debug("Discarded rx packet: len %zd\n", sock_len); + continue; + } /* OK, now we need to know about added descriptors. */ if (!headcount) { if (unlikely(vhost_enable_notify(&net->dev, vq))) { @@ -524,11 +621,11 @@ static void handle_rx(struct vhost_net *net) /* We don't need to be notified again. */ if (unlikely((vhost_hlen))) /* Skip header. TODO: support TSO. */ - move_iovec_hdr(vq->iov, vq->hdr, vhost_hlen, in); + move_iovec_hdr(vq->iov, nvq->hdr, vhost_hlen, in); else /* Copy the header for use in VIRTIO_NET_F_MRG_RXBUF: * needed because recvmsg can modify msg_iov. */ - copy_iovec_hdr(vq->iov, vq->hdr, sock_hlen, in); + copy_iovec_hdr(vq->iov, nvq->hdr, sock_hlen, in); msg.msg_iovlen = in; err = sock->ops->recvmsg(NULL, sock, &msg, sock_len, MSG_DONTWAIT | MSG_TRUNC); @@ -542,7 +639,7 @@ static void handle_rx(struct vhost_net *net) continue; } if (unlikely(vhost_hlen) && - memcpy_toiovecend(vq->hdr, (unsigned char *)&hdr, 0, + memcpy_toiovecend(nvq->hdr, (unsigned char *)&hdr, 0, vhost_hlen)) { vq_err(vq, "Unable to write vnet_hdr at addr %p\n", vq->iov->iov_base); @@ -550,7 +647,7 @@ static void handle_rx(struct vhost_net *net) } /* TODO: Should check and handle checksum. */ if (likely(mergeable) && - memcpy_toiovecend(vq->hdr, (unsigned char *)&headcount, + memcpy_toiovecend(nvq->hdr, (unsigned char *)&headcount, offsetof(typeof(hdr), num_buffers), sizeof hdr.num_buffers)) { vq_err(vq, "Failed num_buffers write"); @@ -567,7 +664,7 @@ static void handle_rx(struct vhost_net *net) break; } } - +out: mutex_unlock(&vq->mutex); } @@ -605,25 +702,40 @@ static void handle_rx_net(struct vhost_work *work) static int vhost_net_open(struct inode *inode, struct file *f) { - struct vhost_net *n = kmalloc(sizeof *n, GFP_KERNEL); + struct vhost_net *n; struct vhost_dev *dev; - int r; + struct vhost_virtqueue **vqs; + int i; - if (!n) + n = kmalloc(sizeof *n, GFP_KERNEL | __GFP_NOWARN | __GFP_REPEAT); + if (!n) { + n = vmalloc(sizeof *n); + if (!n) + return -ENOMEM; + } + vqs = kmalloc(VHOST_NET_VQ_MAX * sizeof(*vqs), GFP_KERNEL); + if (!vqs) { + kvfree(n); return -ENOMEM; + } dev = &n->dev; - n->vqs[VHOST_NET_VQ_TX].handle_kick = handle_tx_kick; - n->vqs[VHOST_NET_VQ_RX].handle_kick = handle_rx_kick; - r = vhost_dev_init(dev, n->vqs, VHOST_NET_VQ_MAX); - if (r < 0) { - kfree(n); - return r; + vqs[VHOST_NET_VQ_TX] = &n->vqs[VHOST_NET_VQ_TX].vq; + vqs[VHOST_NET_VQ_RX] = &n->vqs[VHOST_NET_VQ_RX].vq; + n->vqs[VHOST_NET_VQ_TX].vq.handle_kick = handle_tx_kick; + n->vqs[VHOST_NET_VQ_RX].vq.handle_kick = handle_rx_kick; + for (i = 0; i < VHOST_NET_VQ_MAX; i++) { + n->vqs[i].ubufs = NULL; + n->vqs[i].ubuf_info = NULL; + n->vqs[i].upend_idx = 0; + n->vqs[i].done_idx = 0; + n->vqs[i].vhost_hlen = 0; + n->vqs[i].sock_hlen = 0; } + vhost_dev_init(dev, vqs, VHOST_NET_VQ_MAX); vhost_poll_init(n->poll + VHOST_NET_VQ_TX, handle_tx_net, POLLOUT, dev); vhost_poll_init(n->poll + VHOST_NET_VQ_RX, handle_rx_net, POLLIN, dev); - n->tx_poll_state = VHOST_NET_POLL_DISABLED; f->private_data = n; @@ -633,29 +745,27 @@ static int vhost_net_open(struct inode *inode, struct file *f) static void vhost_net_disable_vq(struct vhost_net *n, struct vhost_virtqueue *vq) { + struct vhost_net_virtqueue *nvq = + container_of(vq, struct vhost_net_virtqueue, vq); + struct vhost_poll *poll = n->poll + (nvq - n->vqs); if (!vq->private_data) return; - if (vq == n->vqs + VHOST_NET_VQ_TX) { - tx_poll_stop(n); - n->tx_poll_state = VHOST_NET_POLL_DISABLED; - } else - vhost_poll_stop(n->poll + VHOST_NET_VQ_RX); + vhost_poll_stop(poll); } -static void vhost_net_enable_vq(struct vhost_net *n, +static int vhost_net_enable_vq(struct vhost_net *n, struct vhost_virtqueue *vq) { + struct vhost_net_virtqueue *nvq = + container_of(vq, struct vhost_net_virtqueue, vq); + struct vhost_poll *poll = n->poll + (nvq - n->vqs); struct socket *sock; - sock = rcu_dereference_protected(vq->private_data, - lockdep_is_held(&vq->mutex)); + sock = vq->private_data; if (!sock) - return; - if (vq == n->vqs + VHOST_NET_VQ_TX) { - n->tx_poll_state = VHOST_NET_POLL_STOPPED; - tx_poll_start(n, sock); - } else - vhost_poll_start(n->poll + VHOST_NET_VQ_RX, sock->file); + return 0; + + return vhost_poll_start(poll, sock->file); } static struct socket *vhost_net_stop_vq(struct vhost_net *n, @@ -664,10 +774,9 @@ static struct socket *vhost_net_stop_vq(struct vhost_net *n, struct socket *sock; mutex_lock(&vq->mutex); - sock = rcu_dereference_protected(vq->private_data, - lockdep_is_held(&vq->mutex)); + sock = vq->private_data; vhost_net_disable_vq(n, vq); - rcu_assign_pointer(vq->private_data, NULL); + vq->private_data = NULL; mutex_unlock(&vq->mutex); return sock; } @@ -675,30 +784,30 @@ static struct socket *vhost_net_stop_vq(struct vhost_net *n, static void vhost_net_stop(struct vhost_net *n, struct socket **tx_sock, struct socket **rx_sock) { - *tx_sock = vhost_net_stop_vq(n, n->vqs + VHOST_NET_VQ_TX); - *rx_sock = vhost_net_stop_vq(n, n->vqs + VHOST_NET_VQ_RX); + *tx_sock = vhost_net_stop_vq(n, &n->vqs[VHOST_NET_VQ_TX].vq); + *rx_sock = vhost_net_stop_vq(n, &n->vqs[VHOST_NET_VQ_RX].vq); } static void vhost_net_flush_vq(struct vhost_net *n, int index) { vhost_poll_flush(n->poll + index); - vhost_poll_flush(&n->dev.vqs[index].poll); + vhost_poll_flush(&n->vqs[index].vq.poll); } static void vhost_net_flush(struct vhost_net *n) { vhost_net_flush_vq(n, VHOST_NET_VQ_TX); vhost_net_flush_vq(n, VHOST_NET_VQ_RX); - if (n->dev.vqs[VHOST_NET_VQ_TX].ubufs) { - mutex_lock(&n->dev.vqs[VHOST_NET_VQ_TX].mutex); + if (n->vqs[VHOST_NET_VQ_TX].ubufs) { + mutex_lock(&n->vqs[VHOST_NET_VQ_TX].vq.mutex); n->tx_flush = true; - mutex_unlock(&n->dev.vqs[VHOST_NET_VQ_TX].mutex); + mutex_unlock(&n->vqs[VHOST_NET_VQ_TX].vq.mutex); /* Wait for all lower device DMAs done. */ - vhost_ubuf_put_and_wait(n->dev.vqs[VHOST_NET_VQ_TX].ubufs); - mutex_lock(&n->dev.vqs[VHOST_NET_VQ_TX].mutex); + vhost_net_ubuf_put_and_wait(n->vqs[VHOST_NET_VQ_TX].ubufs); + mutex_lock(&n->vqs[VHOST_NET_VQ_TX].vq.mutex); n->tx_flush = false; - kref_init(&n->dev.vqs[VHOST_NET_VQ_TX].ubufs->kref); - mutex_unlock(&n->dev.vqs[VHOST_NET_VQ_TX].mutex); + atomic_set(&n->vqs[VHOST_NET_VQ_TX].ubufs->refcount, 1); + mutex_unlock(&n->vqs[VHOST_NET_VQ_TX].vq.mutex); } } @@ -712,14 +821,18 @@ static int vhost_net_release(struct inode *inode, struct file *f) vhost_net_flush(n); vhost_dev_stop(&n->dev); vhost_dev_cleanup(&n->dev, false); + vhost_net_vq_reset(n); if (tx_sock) - fput(tx_sock->file); + sockfd_put(tx_sock); if (rx_sock) - fput(rx_sock->file); + sockfd_put(rx_sock); + /* Make sure no callbacks are outstanding */ + synchronize_rcu_bh(); /* We do an extra flush before freeing memory, * since jobs can re-queue themselves. */ vhost_net_flush(n); - kfree(n); + kfree(n->dev.vqs); + kvfree(n); return 0; } @@ -752,7 +865,7 @@ static struct socket *get_raw_socket(int fd) } return sock; err: - fput(sock->file); + sockfd_put(sock); return ERR_PTR(r); } @@ -792,7 +905,8 @@ static long vhost_net_set_backend(struct vhost_net *n, unsigned index, int fd) { struct socket *sock, *oldsock; struct vhost_virtqueue *vq; - struct vhost_ubuf_ref *ubufs, *oldubufs = NULL; + struct vhost_net_virtqueue *nvq; + struct vhost_net_ubuf_ref *ubufs, *oldubufs = NULL; int r; mutex_lock(&n->dev.mutex); @@ -804,7 +918,8 @@ static long vhost_net_set_backend(struct vhost_net *n, unsigned index, int fd) r = -ENOBUFS; goto err; } - vq = n->vqs + index; + vq = &n->vqs[index].vq; + nvq = &n->vqs[index]; mutex_lock(&vq->mutex); /* Verify that ring has been setup correctly. */ @@ -819,23 +934,26 @@ static long vhost_net_set_backend(struct vhost_net *n, unsigned index, int fd) } /* start polling new socket */ - oldsock = rcu_dereference_protected(vq->private_data, - lockdep_is_held(&vq->mutex)); + oldsock = vq->private_data; if (sock != oldsock) { - ubufs = vhost_ubuf_alloc(vq, sock && vhost_sock_zcopy(sock)); + ubufs = vhost_net_ubuf_alloc(vq, + sock && vhost_sock_zcopy(sock)); if (IS_ERR(ubufs)) { r = PTR_ERR(ubufs); goto err_ubufs; } - oldubufs = vq->ubufs; - vq->ubufs = ubufs; - vhost_net_disable_vq(n, vq); - rcu_assign_pointer(vq->private_data, sock); - vhost_net_enable_vq(n, vq); + vhost_net_disable_vq(n, vq); + vq->private_data = sock; r = vhost_init_used(vq); if (r) - goto err_vq; + goto err_used; + r = vhost_net_enable_vq(n, vq); + if (r) + goto err_used; + + oldubufs = nvq->ubufs; + nvq->ubufs = ubufs; n->tx_packets = 0; n->tx_zcopy_err = 0; @@ -845,7 +963,7 @@ static long vhost_net_set_backend(struct vhost_net *n, unsigned index, int fd) mutex_unlock(&vq->mutex); if (oldubufs) { - vhost_ubuf_put_and_wait(oldubufs); + vhost_net_ubuf_put_wait_and_free(oldubufs); mutex_lock(&vq->mutex); vhost_zerocopy_signal_used(n, vq); mutex_unlock(&vq->mutex); @@ -853,14 +971,19 @@ static long vhost_net_set_backend(struct vhost_net *n, unsigned index, int fd) if (oldsock) { vhost_net_flush_vq(n, index); - fput(oldsock->file); + sockfd_put(oldsock); } mutex_unlock(&n->dev.mutex); return 0; +err_used: + vq->private_data = oldsock; + vhost_net_enable_vq(n, vq); + if (ubufs) + vhost_net_ubuf_put_wait_and_free(ubufs); err_ubufs: - fput(sock->file); + sockfd_put(sock); err_vq: mutex_unlock(&vq->mutex); err: @@ -873,20 +996,27 @@ static long vhost_net_reset_owner(struct vhost_net *n) struct socket *tx_sock = NULL; struct socket *rx_sock = NULL; long err; + struct vhost_memory *memory; mutex_lock(&n->dev.mutex); err = vhost_dev_check_owner(&n->dev); if (err) goto done; + memory = vhost_dev_reset_owner_prepare(); + if (!memory) { + err = -ENOMEM; + goto done; + } vhost_net_stop(n, &tx_sock, &rx_sock); vhost_net_flush(n); - err = vhost_dev_reset_owner(&n->dev); + vhost_dev_reset_owner(&n->dev, memory); + vhost_net_vq_reset(n); done: mutex_unlock(&n->dev.mutex); if (tx_sock) - fput(tx_sock->file); + sockfd_put(tx_sock); if (rx_sock) - fput(rx_sock->file); + sockfd_put(rx_sock); return err; } @@ -913,19 +1043,38 @@ static int vhost_net_set_features(struct vhost_net *n, u64 features) mutex_unlock(&n->dev.mutex); return -EFAULT; } - n->dev.acked_features = features; - smp_wmb(); for (i = 0; i < VHOST_NET_VQ_MAX; ++i) { - mutex_lock(&n->vqs[i].mutex); + mutex_lock(&n->vqs[i].vq.mutex); + n->vqs[i].vq.acked_features = features; n->vqs[i].vhost_hlen = vhost_hlen; n->vqs[i].sock_hlen = sock_hlen; - mutex_unlock(&n->vqs[i].mutex); + mutex_unlock(&n->vqs[i].vq.mutex); } - vhost_net_flush(n); mutex_unlock(&n->dev.mutex); return 0; } +static long vhost_net_set_owner(struct vhost_net *n) +{ + int r; + + mutex_lock(&n->dev.mutex); + if (vhost_dev_has_owner(&n->dev)) { + r = -EBUSY; + goto out; + } + r = vhost_net_set_ubuf_info(n); + if (r) + goto out; + r = vhost_dev_set_owner(&n->dev); + if (r) + vhost_net_clear_ubuf_info(n); + vhost_net_flush(n); +out: + mutex_unlock(&n->dev.mutex); + return r; +} + static long vhost_net_ioctl(struct file *f, unsigned int ioctl, unsigned long arg) { @@ -954,6 +1103,8 @@ static long vhost_net_ioctl(struct file *f, unsigned int ioctl, return vhost_net_set_features(n, features); case VHOST_RESET_OWNER: return vhost_net_reset_owner(n); + case VHOST_SET_OWNER: + return vhost_net_set_owner(n); default: mutex_lock(&n->dev.mutex); r = vhost_dev_ioctl(&n->dev, ioctl, argp); @@ -994,7 +1145,7 @@ static struct miscdevice vhost_net_misc = { static int vhost_net_init(void) { if (experimental_zcopytx) - vhost_enable_zcopy(VHOST_NET_VQ_TX); + vhost_net_enable_zcopy(VHOST_NET_VQ_TX); return misc_register(&vhost_net_misc); } module_init(vhost_net_init); diff --git a/drivers/vhost/scsi.c b/drivers/vhost/scsi.c new file mode 100644 index 00000000000..69906cacd04 --- /dev/null +++ b/drivers/vhost/scsi.c @@ -0,0 +1,2367 @@ +/******************************************************************************* + * Vhost kernel TCM fabric driver for virtio SCSI initiators + * + * (C) Copyright 2010-2013 Datera, Inc. + * (C) Copyright 2010-2012 IBM Corp. + * + * Licensed to the Linux Foundation under the General Public License (GPL) version 2. + * + * Authors: Nicholas A. Bellinger <nab@daterainc.com> + * Stefan Hajnoczi <stefanha@linux.vnet.ibm.com> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + ****************************************************************************/ + +#include <linux/module.h> +#include <linux/moduleparam.h> +#include <generated/utsrelease.h> +#include <linux/utsname.h> +#include <linux/init.h> +#include <linux/slab.h> +#include <linux/kthread.h> +#include <linux/types.h> +#include <linux/string.h> +#include <linux/configfs.h> +#include <linux/ctype.h> +#include <linux/compat.h> +#include <linux/eventfd.h> +#include <linux/fs.h> +#include <linux/miscdevice.h> +#include <asm/unaligned.h> +#include <scsi/scsi.h> +#include <scsi/scsi_tcq.h> +#include <target/target_core_base.h> +#include <target/target_core_fabric.h> +#include <target/target_core_fabric_configfs.h> +#include <target/target_core_configfs.h> +#include <target/configfs_macros.h> +#include <linux/vhost.h> +#include <linux/virtio_scsi.h> +#include <linux/llist.h> +#include <linux/bitmap.h> +#include <linux/percpu_ida.h> + +#include "vhost.h" + +#define TCM_VHOST_VERSION "v0.1" +#define TCM_VHOST_NAMELEN 256 +#define TCM_VHOST_MAX_CDB_SIZE 32 +#define TCM_VHOST_DEFAULT_TAGS 256 +#define TCM_VHOST_PREALLOC_SGLS 2048 +#define TCM_VHOST_PREALLOC_UPAGES 2048 +#define TCM_VHOST_PREALLOC_PROT_SGLS 512 + +struct vhost_scsi_inflight { + /* Wait for the flush operation to finish */ + struct completion comp; + /* Refcount for the inflight reqs */ + struct kref kref; +}; + +struct tcm_vhost_cmd { + /* Descriptor from vhost_get_vq_desc() for virt_queue segment */ + int tvc_vq_desc; + /* virtio-scsi initiator task attribute */ + int tvc_task_attr; + /* virtio-scsi initiator data direction */ + enum dma_data_direction tvc_data_direction; + /* Expected data transfer length from virtio-scsi header */ + u32 tvc_exp_data_len; + /* The Tag from include/linux/virtio_scsi.h:struct virtio_scsi_cmd_req */ + u64 tvc_tag; + /* The number of scatterlists associated with this cmd */ + u32 tvc_sgl_count; + u32 tvc_prot_sgl_count; + /* Saved unpacked SCSI LUN for tcm_vhost_submission_work() */ + u32 tvc_lun; + /* Pointer to the SGL formatted memory from virtio-scsi */ + struct scatterlist *tvc_sgl; + struct scatterlist *tvc_prot_sgl; + struct page **tvc_upages; + /* Pointer to response */ + struct virtio_scsi_cmd_resp __user *tvc_resp; + /* Pointer to vhost_scsi for our device */ + struct vhost_scsi *tvc_vhost; + /* Pointer to vhost_virtqueue for the cmd */ + struct vhost_virtqueue *tvc_vq; + /* Pointer to vhost nexus memory */ + struct tcm_vhost_nexus *tvc_nexus; + /* The TCM I/O descriptor that is accessed via container_of() */ + struct se_cmd tvc_se_cmd; + /* work item used for cmwq dispatch to tcm_vhost_submission_work() */ + struct work_struct work; + /* Copy of the incoming SCSI command descriptor block (CDB) */ + unsigned char tvc_cdb[TCM_VHOST_MAX_CDB_SIZE]; + /* Sense buffer that will be mapped into outgoing status */ + unsigned char tvc_sense_buf[TRANSPORT_SENSE_BUFFER]; + /* Completed commands list, serviced from vhost worker thread */ + struct llist_node tvc_completion_list; + /* Used to track inflight cmd */ + struct vhost_scsi_inflight *inflight; +}; + +struct tcm_vhost_nexus { + /* Pointer to TCM session for I_T Nexus */ + struct se_session *tvn_se_sess; +}; + +struct tcm_vhost_nacl { + /* Binary World Wide unique Port Name for Vhost Initiator port */ + u64 iport_wwpn; + /* ASCII formatted WWPN for Sas Initiator port */ + char iport_name[TCM_VHOST_NAMELEN]; + /* Returned by tcm_vhost_make_nodeacl() */ + struct se_node_acl se_node_acl; +}; + +struct tcm_vhost_tpg { + /* Vhost port target portal group tag for TCM */ + u16 tport_tpgt; + /* Used to track number of TPG Port/Lun Links wrt to explict I_T Nexus shutdown */ + int tv_tpg_port_count; + /* Used for vhost_scsi device reference to tpg_nexus, protected by tv_tpg_mutex */ + int tv_tpg_vhost_count; + /* list for tcm_vhost_list */ + struct list_head tv_tpg_list; + /* Used to protect access for tpg_nexus */ + struct mutex tv_tpg_mutex; + /* Pointer to the TCM VHost I_T Nexus for this TPG endpoint */ + struct tcm_vhost_nexus *tpg_nexus; + /* Pointer back to tcm_vhost_tport */ + struct tcm_vhost_tport *tport; + /* Returned by tcm_vhost_make_tpg() */ + struct se_portal_group se_tpg; + /* Pointer back to vhost_scsi, protected by tv_tpg_mutex */ + struct vhost_scsi *vhost_scsi; +}; + +struct tcm_vhost_tport { + /* SCSI protocol the tport is providing */ + u8 tport_proto_id; + /* Binary World Wide unique Port Name for Vhost Target port */ + u64 tport_wwpn; + /* ASCII formatted WWPN for Vhost Target port */ + char tport_name[TCM_VHOST_NAMELEN]; + /* Returned by tcm_vhost_make_tport() */ + struct se_wwn tport_wwn; +}; + +struct tcm_vhost_evt { + /* event to be sent to guest */ + struct virtio_scsi_event event; + /* event list, serviced from vhost worker thread */ + struct llist_node list; +}; + +enum { + VHOST_SCSI_VQ_CTL = 0, + VHOST_SCSI_VQ_EVT = 1, + VHOST_SCSI_VQ_IO = 2, +}; + +enum { + VHOST_SCSI_FEATURES = VHOST_FEATURES | (1ULL << VIRTIO_SCSI_F_HOTPLUG) | + (1ULL << VIRTIO_SCSI_F_T10_PI) +}; + +#define VHOST_SCSI_MAX_TARGET 256 +#define VHOST_SCSI_MAX_VQ 128 +#define VHOST_SCSI_MAX_EVENT 128 + +struct vhost_scsi_virtqueue { + struct vhost_virtqueue vq; + /* + * Reference counting for inflight reqs, used for flush operation. At + * each time, one reference tracks new commands submitted, while we + * wait for another one to reach 0. + */ + struct vhost_scsi_inflight inflights[2]; + /* + * Indicate current inflight in use, protected by vq->mutex. + * Writers must also take dev mutex and flush under it. + */ + int inflight_idx; +}; + +struct vhost_scsi { + /* Protected by vhost_scsi->dev.mutex */ + struct tcm_vhost_tpg **vs_tpg; + char vs_vhost_wwpn[TRANSPORT_IQN_LEN]; + + struct vhost_dev dev; + struct vhost_scsi_virtqueue vqs[VHOST_SCSI_MAX_VQ]; + + struct vhost_work vs_completion_work; /* cmd completion work item */ + struct llist_head vs_completion_list; /* cmd completion queue */ + + struct vhost_work vs_event_work; /* evt injection work item */ + struct llist_head vs_event_list; /* evt injection queue */ + + bool vs_events_missed; /* any missed events, protected by vq->mutex */ + int vs_events_nr; /* num of pending events, protected by vq->mutex */ +}; + +/* Local pointer to allocated TCM configfs fabric module */ +static struct target_fabric_configfs *tcm_vhost_fabric_configfs; + +static struct workqueue_struct *tcm_vhost_workqueue; + +/* Global spinlock to protect tcm_vhost TPG list for vhost IOCTL access */ +static DEFINE_MUTEX(tcm_vhost_mutex); +static LIST_HEAD(tcm_vhost_list); + +static int iov_num_pages(struct iovec *iov) +{ + return (PAGE_ALIGN((unsigned long)iov->iov_base + iov->iov_len) - + ((unsigned long)iov->iov_base & PAGE_MASK)) >> PAGE_SHIFT; +} + +static void tcm_vhost_done_inflight(struct kref *kref) +{ + struct vhost_scsi_inflight *inflight; + + inflight = container_of(kref, struct vhost_scsi_inflight, kref); + complete(&inflight->comp); +} + +static void tcm_vhost_init_inflight(struct vhost_scsi *vs, + struct vhost_scsi_inflight *old_inflight[]) +{ + struct vhost_scsi_inflight *new_inflight; + struct vhost_virtqueue *vq; + int idx, i; + + for (i = 0; i < VHOST_SCSI_MAX_VQ; i++) { + vq = &vs->vqs[i].vq; + + mutex_lock(&vq->mutex); + + /* store old infight */ + idx = vs->vqs[i].inflight_idx; + if (old_inflight) + old_inflight[i] = &vs->vqs[i].inflights[idx]; + + /* setup new infight */ + vs->vqs[i].inflight_idx = idx ^ 1; + new_inflight = &vs->vqs[i].inflights[idx ^ 1]; + kref_init(&new_inflight->kref); + init_completion(&new_inflight->comp); + + mutex_unlock(&vq->mutex); + } +} + +static struct vhost_scsi_inflight * +tcm_vhost_get_inflight(struct vhost_virtqueue *vq) +{ + struct vhost_scsi_inflight *inflight; + struct vhost_scsi_virtqueue *svq; + + svq = container_of(vq, struct vhost_scsi_virtqueue, vq); + inflight = &svq->inflights[svq->inflight_idx]; + kref_get(&inflight->kref); + + return inflight; +} + +static void tcm_vhost_put_inflight(struct vhost_scsi_inflight *inflight) +{ + kref_put(&inflight->kref, tcm_vhost_done_inflight); +} + +static int tcm_vhost_check_true(struct se_portal_group *se_tpg) +{ + return 1; +} + +static int tcm_vhost_check_false(struct se_portal_group *se_tpg) +{ + return 0; +} + +static char *tcm_vhost_get_fabric_name(void) +{ + return "vhost"; +} + +static u8 tcm_vhost_get_fabric_proto_ident(struct se_portal_group *se_tpg) +{ + struct tcm_vhost_tpg *tpg = container_of(se_tpg, + struct tcm_vhost_tpg, se_tpg); + struct tcm_vhost_tport *tport = tpg->tport; + + switch (tport->tport_proto_id) { + case SCSI_PROTOCOL_SAS: + return sas_get_fabric_proto_ident(se_tpg); + case SCSI_PROTOCOL_FCP: + return fc_get_fabric_proto_ident(se_tpg); + case SCSI_PROTOCOL_ISCSI: + return iscsi_get_fabric_proto_ident(se_tpg); + default: + pr_err("Unknown tport_proto_id: 0x%02x, using" + " SAS emulation\n", tport->tport_proto_id); + break; + } + + return sas_get_fabric_proto_ident(se_tpg); +} + +static char *tcm_vhost_get_fabric_wwn(struct se_portal_group *se_tpg) +{ + struct tcm_vhost_tpg *tpg = container_of(se_tpg, + struct tcm_vhost_tpg, se_tpg); + struct tcm_vhost_tport *tport = tpg->tport; + + return &tport->tport_name[0]; +} + +static u16 tcm_vhost_get_tag(struct se_portal_group *se_tpg) +{ + struct tcm_vhost_tpg *tpg = container_of(se_tpg, + struct tcm_vhost_tpg, se_tpg); + return tpg->tport_tpgt; +} + +static u32 tcm_vhost_get_default_depth(struct se_portal_group *se_tpg) +{ + return 1; +} + +static u32 +tcm_vhost_get_pr_transport_id(struct se_portal_group *se_tpg, + struct se_node_acl *se_nacl, + struct t10_pr_registration *pr_reg, + int *format_code, + unsigned char *buf) +{ + struct tcm_vhost_tpg *tpg = container_of(se_tpg, + struct tcm_vhost_tpg, se_tpg); + struct tcm_vhost_tport *tport = tpg->tport; + + switch (tport->tport_proto_id) { + case SCSI_PROTOCOL_SAS: + return sas_get_pr_transport_id(se_tpg, se_nacl, pr_reg, + format_code, buf); + case SCSI_PROTOCOL_FCP: + return fc_get_pr_transport_id(se_tpg, se_nacl, pr_reg, + format_code, buf); + case SCSI_PROTOCOL_ISCSI: + return iscsi_get_pr_transport_id(se_tpg, se_nacl, pr_reg, + format_code, buf); + default: + pr_err("Unknown tport_proto_id: 0x%02x, using" + " SAS emulation\n", tport->tport_proto_id); + break; + } + + return sas_get_pr_transport_id(se_tpg, se_nacl, pr_reg, + format_code, buf); +} + +static u32 +tcm_vhost_get_pr_transport_id_len(struct se_portal_group *se_tpg, + struct se_node_acl *se_nacl, + struct t10_pr_registration *pr_reg, + int *format_code) +{ + struct tcm_vhost_tpg *tpg = container_of(se_tpg, + struct tcm_vhost_tpg, se_tpg); + struct tcm_vhost_tport *tport = tpg->tport; + + switch (tport->tport_proto_id) { + case SCSI_PROTOCOL_SAS: + return sas_get_pr_transport_id_len(se_tpg, se_nacl, pr_reg, + format_code); + case SCSI_PROTOCOL_FCP: + return fc_get_pr_transport_id_len(se_tpg, se_nacl, pr_reg, + format_code); + case SCSI_PROTOCOL_ISCSI: + return iscsi_get_pr_transport_id_len(se_tpg, se_nacl, pr_reg, + format_code); + default: + pr_err("Unknown tport_proto_id: 0x%02x, using" + " SAS emulation\n", tport->tport_proto_id); + break; + } + + return sas_get_pr_transport_id_len(se_tpg, se_nacl, pr_reg, + format_code); +} + +static char * +tcm_vhost_parse_pr_out_transport_id(struct se_portal_group *se_tpg, + const char *buf, + u32 *out_tid_len, + char **port_nexus_ptr) +{ + struct tcm_vhost_tpg *tpg = container_of(se_tpg, + struct tcm_vhost_tpg, se_tpg); + struct tcm_vhost_tport *tport = tpg->tport; + + switch (tport->tport_proto_id) { + case SCSI_PROTOCOL_SAS: + return sas_parse_pr_out_transport_id(se_tpg, buf, out_tid_len, + port_nexus_ptr); + case SCSI_PROTOCOL_FCP: + return fc_parse_pr_out_transport_id(se_tpg, buf, out_tid_len, + port_nexus_ptr); + case SCSI_PROTOCOL_ISCSI: + return iscsi_parse_pr_out_transport_id(se_tpg, buf, out_tid_len, + port_nexus_ptr); + default: + pr_err("Unknown tport_proto_id: 0x%02x, using" + " SAS emulation\n", tport->tport_proto_id); + break; + } + + return sas_parse_pr_out_transport_id(se_tpg, buf, out_tid_len, + port_nexus_ptr); +} + +static struct se_node_acl * +tcm_vhost_alloc_fabric_acl(struct se_portal_group *se_tpg) +{ + struct tcm_vhost_nacl *nacl; + + nacl = kzalloc(sizeof(struct tcm_vhost_nacl), GFP_KERNEL); + if (!nacl) { + pr_err("Unable to allocate struct tcm_vhost_nacl\n"); + return NULL; + } + + return &nacl->se_node_acl; +} + +static void +tcm_vhost_release_fabric_acl(struct se_portal_group *se_tpg, + struct se_node_acl *se_nacl) +{ + struct tcm_vhost_nacl *nacl = container_of(se_nacl, + struct tcm_vhost_nacl, se_node_acl); + kfree(nacl); +} + +static u32 tcm_vhost_tpg_get_inst_index(struct se_portal_group *se_tpg) +{ + return 1; +} + +static void tcm_vhost_release_cmd(struct se_cmd *se_cmd) +{ + struct tcm_vhost_cmd *tv_cmd = container_of(se_cmd, + struct tcm_vhost_cmd, tvc_se_cmd); + struct se_session *se_sess = se_cmd->se_sess; + int i; + + if (tv_cmd->tvc_sgl_count) { + for (i = 0; i < tv_cmd->tvc_sgl_count; i++) + put_page(sg_page(&tv_cmd->tvc_sgl[i])); + } + if (tv_cmd->tvc_prot_sgl_count) { + for (i = 0; i < tv_cmd->tvc_prot_sgl_count; i++) + put_page(sg_page(&tv_cmd->tvc_prot_sgl[i])); + } + + tcm_vhost_put_inflight(tv_cmd->inflight); + percpu_ida_free(&se_sess->sess_tag_pool, se_cmd->map_tag); +} + +static int tcm_vhost_shutdown_session(struct se_session *se_sess) +{ + return 0; +} + +static void tcm_vhost_close_session(struct se_session *se_sess) +{ + return; +} + +static u32 tcm_vhost_sess_get_index(struct se_session *se_sess) +{ + return 0; +} + +static int tcm_vhost_write_pending(struct se_cmd *se_cmd) +{ + /* Go ahead and process the write immediately */ + target_execute_cmd(se_cmd); + return 0; +} + +static int tcm_vhost_write_pending_status(struct se_cmd *se_cmd) +{ + return 0; +} + +static void tcm_vhost_set_default_node_attrs(struct se_node_acl *nacl) +{ + return; +} + +static u32 tcm_vhost_get_task_tag(struct se_cmd *se_cmd) +{ + return 0; +} + +static int tcm_vhost_get_cmd_state(struct se_cmd *se_cmd) +{ + return 0; +} + +static void vhost_scsi_complete_cmd(struct tcm_vhost_cmd *cmd) +{ + struct vhost_scsi *vs = cmd->tvc_vhost; + + llist_add(&cmd->tvc_completion_list, &vs->vs_completion_list); + + vhost_work_queue(&vs->dev, &vs->vs_completion_work); +} + +static int tcm_vhost_queue_data_in(struct se_cmd *se_cmd) +{ + struct tcm_vhost_cmd *cmd = container_of(se_cmd, + struct tcm_vhost_cmd, tvc_se_cmd); + vhost_scsi_complete_cmd(cmd); + return 0; +} + +static int tcm_vhost_queue_status(struct se_cmd *se_cmd) +{ + struct tcm_vhost_cmd *cmd = container_of(se_cmd, + struct tcm_vhost_cmd, tvc_se_cmd); + vhost_scsi_complete_cmd(cmd); + return 0; +} + +static void tcm_vhost_queue_tm_rsp(struct se_cmd *se_cmd) +{ + return; +} + +static void tcm_vhost_aborted_task(struct se_cmd *se_cmd) +{ + return; +} + +static void tcm_vhost_free_evt(struct vhost_scsi *vs, struct tcm_vhost_evt *evt) +{ + vs->vs_events_nr--; + kfree(evt); +} + +static struct tcm_vhost_evt * +tcm_vhost_allocate_evt(struct vhost_scsi *vs, + u32 event, u32 reason) +{ + struct vhost_virtqueue *vq = &vs->vqs[VHOST_SCSI_VQ_EVT].vq; + struct tcm_vhost_evt *evt; + + if (vs->vs_events_nr > VHOST_SCSI_MAX_EVENT) { + vs->vs_events_missed = true; + return NULL; + } + + evt = kzalloc(sizeof(*evt), GFP_KERNEL); + if (!evt) { + vq_err(vq, "Failed to allocate tcm_vhost_evt\n"); + vs->vs_events_missed = true; + return NULL; + } + + evt->event.event = event; + evt->event.reason = reason; + vs->vs_events_nr++; + + return evt; +} + +static void vhost_scsi_free_cmd(struct tcm_vhost_cmd *cmd) +{ + struct se_cmd *se_cmd = &cmd->tvc_se_cmd; + + /* TODO locking against target/backend threads? */ + transport_generic_free_cmd(se_cmd, 0); + +} + +static int vhost_scsi_check_stop_free(struct se_cmd *se_cmd) +{ + return target_put_sess_cmd(se_cmd->se_sess, se_cmd); +} + +static void +tcm_vhost_do_evt_work(struct vhost_scsi *vs, struct tcm_vhost_evt *evt) +{ + struct vhost_virtqueue *vq = &vs->vqs[VHOST_SCSI_VQ_EVT].vq; + struct virtio_scsi_event *event = &evt->event; + struct virtio_scsi_event __user *eventp; + unsigned out, in; + int head, ret; + + if (!vq->private_data) { + vs->vs_events_missed = true; + return; + } + +again: + vhost_disable_notify(&vs->dev, vq); + head = vhost_get_vq_desc(vq, vq->iov, + ARRAY_SIZE(vq->iov), &out, &in, + NULL, NULL); + if (head < 0) { + vs->vs_events_missed = true; + return; + } + if (head == vq->num) { + if (vhost_enable_notify(&vs->dev, vq)) + goto again; + vs->vs_events_missed = true; + return; + } + + if ((vq->iov[out].iov_len != sizeof(struct virtio_scsi_event))) { + vq_err(vq, "Expecting virtio_scsi_event, got %zu bytes\n", + vq->iov[out].iov_len); + vs->vs_events_missed = true; + return; + } + + if (vs->vs_events_missed) { + event->event |= VIRTIO_SCSI_T_EVENTS_MISSED; + vs->vs_events_missed = false; + } + + eventp = vq->iov[out].iov_base; + ret = __copy_to_user(eventp, event, sizeof(*event)); + if (!ret) + vhost_add_used_and_signal(&vs->dev, vq, head, 0); + else + vq_err(vq, "Faulted on tcm_vhost_send_event\n"); +} + +static void tcm_vhost_evt_work(struct vhost_work *work) +{ + struct vhost_scsi *vs = container_of(work, struct vhost_scsi, + vs_event_work); + struct vhost_virtqueue *vq = &vs->vqs[VHOST_SCSI_VQ_EVT].vq; + struct tcm_vhost_evt *evt; + struct llist_node *llnode; + + mutex_lock(&vq->mutex); + llnode = llist_del_all(&vs->vs_event_list); + while (llnode) { + evt = llist_entry(llnode, struct tcm_vhost_evt, list); + llnode = llist_next(llnode); + tcm_vhost_do_evt_work(vs, evt); + tcm_vhost_free_evt(vs, evt); + } + mutex_unlock(&vq->mutex); +} + +/* Fill in status and signal that we are done processing this command + * + * This is scheduled in the vhost work queue so we are called with the owner + * process mm and can access the vring. + */ +static void vhost_scsi_complete_cmd_work(struct vhost_work *work) +{ + struct vhost_scsi *vs = container_of(work, struct vhost_scsi, + vs_completion_work); + DECLARE_BITMAP(signal, VHOST_SCSI_MAX_VQ); + struct virtio_scsi_cmd_resp v_rsp; + struct tcm_vhost_cmd *cmd; + struct llist_node *llnode; + struct se_cmd *se_cmd; + int ret, vq; + + bitmap_zero(signal, VHOST_SCSI_MAX_VQ); + llnode = llist_del_all(&vs->vs_completion_list); + while (llnode) { + cmd = llist_entry(llnode, struct tcm_vhost_cmd, + tvc_completion_list); + llnode = llist_next(llnode); + se_cmd = &cmd->tvc_se_cmd; + + pr_debug("%s tv_cmd %p resid %u status %#02x\n", __func__, + cmd, se_cmd->residual_count, se_cmd->scsi_status); + + memset(&v_rsp, 0, sizeof(v_rsp)); + v_rsp.resid = se_cmd->residual_count; + /* TODO is status_qualifier field needed? */ + v_rsp.status = se_cmd->scsi_status; + v_rsp.sense_len = se_cmd->scsi_sense_length; + memcpy(v_rsp.sense, cmd->tvc_sense_buf, + v_rsp.sense_len); + ret = copy_to_user(cmd->tvc_resp, &v_rsp, sizeof(v_rsp)); + if (likely(ret == 0)) { + struct vhost_scsi_virtqueue *q; + vhost_add_used(cmd->tvc_vq, cmd->tvc_vq_desc, 0); + q = container_of(cmd->tvc_vq, struct vhost_scsi_virtqueue, vq); + vq = q - vs->vqs; + __set_bit(vq, signal); + } else + pr_err("Faulted on virtio_scsi_cmd_resp\n"); + + vhost_scsi_free_cmd(cmd); + } + + vq = -1; + while ((vq = find_next_bit(signal, VHOST_SCSI_MAX_VQ, vq + 1)) + < VHOST_SCSI_MAX_VQ) + vhost_signal(&vs->dev, &vs->vqs[vq].vq); +} + +static struct tcm_vhost_cmd * +vhost_scsi_get_tag(struct vhost_virtqueue *vq, struct tcm_vhost_tpg *tpg, + unsigned char *cdb, u64 scsi_tag, u16 lun, u8 task_attr, + u32 exp_data_len, int data_direction) +{ + struct tcm_vhost_cmd *cmd; + struct tcm_vhost_nexus *tv_nexus; + struct se_session *se_sess; + struct scatterlist *sg, *prot_sg; + struct page **pages; + int tag; + + tv_nexus = tpg->tpg_nexus; + if (!tv_nexus) { + pr_err("Unable to locate active struct tcm_vhost_nexus\n"); + return ERR_PTR(-EIO); + } + se_sess = tv_nexus->tvn_se_sess; + + tag = percpu_ida_alloc(&se_sess->sess_tag_pool, TASK_RUNNING); + if (tag < 0) { + pr_err("Unable to obtain tag for tcm_vhost_cmd\n"); + return ERR_PTR(-ENOMEM); + } + + cmd = &((struct tcm_vhost_cmd *)se_sess->sess_cmd_map)[tag]; + sg = cmd->tvc_sgl; + prot_sg = cmd->tvc_prot_sgl; + pages = cmd->tvc_upages; + memset(cmd, 0, sizeof(struct tcm_vhost_cmd)); + + cmd->tvc_sgl = sg; + cmd->tvc_prot_sgl = prot_sg; + cmd->tvc_upages = pages; + cmd->tvc_se_cmd.map_tag = tag; + cmd->tvc_tag = scsi_tag; + cmd->tvc_lun = lun; + cmd->tvc_task_attr = task_attr; + cmd->tvc_exp_data_len = exp_data_len; + cmd->tvc_data_direction = data_direction; + cmd->tvc_nexus = tv_nexus; + cmd->inflight = tcm_vhost_get_inflight(vq); + + memcpy(cmd->tvc_cdb, cdb, TCM_VHOST_MAX_CDB_SIZE); + + return cmd; +} + +/* + * Map a user memory range into a scatterlist + * + * Returns the number of scatterlist entries used or -errno on error. + */ +static int +vhost_scsi_map_to_sgl(struct tcm_vhost_cmd *tv_cmd, + struct scatterlist *sgl, + unsigned int sgl_count, + struct iovec *iov, + struct page **pages, + bool write) +{ + unsigned int npages = 0, pages_nr, offset, nbytes; + struct scatterlist *sg = sgl; + void __user *ptr = iov->iov_base; + size_t len = iov->iov_len; + int ret, i; + + pages_nr = iov_num_pages(iov); + if (pages_nr > sgl_count) { + pr_err("vhost_scsi_map_to_sgl() pages_nr: %u greater than" + " sgl_count: %u\n", pages_nr, sgl_count); + return -ENOBUFS; + } + if (pages_nr > TCM_VHOST_PREALLOC_UPAGES) { + pr_err("vhost_scsi_map_to_sgl() pages_nr: %u greater than" + " preallocated TCM_VHOST_PREALLOC_UPAGES: %u\n", + pages_nr, TCM_VHOST_PREALLOC_UPAGES); + return -ENOBUFS; + } + + ret = get_user_pages_fast((unsigned long)ptr, pages_nr, write, pages); + /* No pages were pinned */ + if (ret < 0) + goto out; + /* Less pages pinned than wanted */ + if (ret != pages_nr) { + for (i = 0; i < ret; i++) + put_page(pages[i]); + ret = -EFAULT; + goto out; + } + + while (len > 0) { + offset = (uintptr_t)ptr & ~PAGE_MASK; + nbytes = min_t(unsigned int, PAGE_SIZE - offset, len); + sg_set_page(sg, pages[npages], nbytes, offset); + ptr += nbytes; + len -= nbytes; + sg++; + npages++; + } + +out: + return ret; +} + +static int +vhost_scsi_map_iov_to_sgl(struct tcm_vhost_cmd *cmd, + struct iovec *iov, + int niov, + bool write) +{ + struct scatterlist *sg = cmd->tvc_sgl; + unsigned int sgl_count = 0; + int ret, i; + + for (i = 0; i < niov; i++) + sgl_count += iov_num_pages(&iov[i]); + + if (sgl_count > TCM_VHOST_PREALLOC_SGLS) { + pr_err("vhost_scsi_map_iov_to_sgl() sgl_count: %u greater than" + " preallocated TCM_VHOST_PREALLOC_SGLS: %u\n", + sgl_count, TCM_VHOST_PREALLOC_SGLS); + return -ENOBUFS; + } + + pr_debug("%s sg %p sgl_count %u\n", __func__, sg, sgl_count); + sg_init_table(sg, sgl_count); + cmd->tvc_sgl_count = sgl_count; + + pr_debug("Mapping iovec %p for %u pages\n", &iov[0], sgl_count); + + for (i = 0; i < niov; i++) { + ret = vhost_scsi_map_to_sgl(cmd, sg, sgl_count, &iov[i], + cmd->tvc_upages, write); + if (ret < 0) { + for (i = 0; i < cmd->tvc_sgl_count; i++) + put_page(sg_page(&cmd->tvc_sgl[i])); + + cmd->tvc_sgl_count = 0; + return ret; + } + sg += ret; + sgl_count -= ret; + } + return 0; +} + +static int +vhost_scsi_map_iov_to_prot(struct tcm_vhost_cmd *cmd, + struct iovec *iov, + int niov, + bool write) +{ + struct scatterlist *prot_sg = cmd->tvc_prot_sgl; + unsigned int prot_sgl_count = 0; + int ret, i; + + for (i = 0; i < niov; i++) + prot_sgl_count += iov_num_pages(&iov[i]); + + if (prot_sgl_count > TCM_VHOST_PREALLOC_PROT_SGLS) { + pr_err("vhost_scsi_map_iov_to_prot() sgl_count: %u greater than" + " preallocated TCM_VHOST_PREALLOC_PROT_SGLS: %u\n", + prot_sgl_count, TCM_VHOST_PREALLOC_PROT_SGLS); + return -ENOBUFS; + } + + pr_debug("%s prot_sg %p prot_sgl_count %u\n", __func__, + prot_sg, prot_sgl_count); + sg_init_table(prot_sg, prot_sgl_count); + cmd->tvc_prot_sgl_count = prot_sgl_count; + + for (i = 0; i < niov; i++) { + ret = vhost_scsi_map_to_sgl(cmd, prot_sg, prot_sgl_count, &iov[i], + cmd->tvc_upages, write); + if (ret < 0) { + for (i = 0; i < cmd->tvc_prot_sgl_count; i++) + put_page(sg_page(&cmd->tvc_prot_sgl[i])); + + cmd->tvc_prot_sgl_count = 0; + return ret; + } + prot_sg += ret; + prot_sgl_count -= ret; + } + return 0; +} + +static void tcm_vhost_submission_work(struct work_struct *work) +{ + struct tcm_vhost_cmd *cmd = + container_of(work, struct tcm_vhost_cmd, work); + struct tcm_vhost_nexus *tv_nexus; + struct se_cmd *se_cmd = &cmd->tvc_se_cmd; + struct scatterlist *sg_ptr, *sg_prot_ptr = NULL; + int rc; + + /* FIXME: BIDI operation */ + if (cmd->tvc_sgl_count) { + sg_ptr = cmd->tvc_sgl; + + if (cmd->tvc_prot_sgl_count) + sg_prot_ptr = cmd->tvc_prot_sgl; + else + se_cmd->prot_pto = true; + } else { + sg_ptr = NULL; + } + tv_nexus = cmd->tvc_nexus; + + rc = target_submit_cmd_map_sgls(se_cmd, tv_nexus->tvn_se_sess, + cmd->tvc_cdb, &cmd->tvc_sense_buf[0], + cmd->tvc_lun, cmd->tvc_exp_data_len, + cmd->tvc_task_attr, cmd->tvc_data_direction, + TARGET_SCF_ACK_KREF, sg_ptr, cmd->tvc_sgl_count, + NULL, 0, sg_prot_ptr, cmd->tvc_prot_sgl_count); + if (rc < 0) { + transport_send_check_condition_and_sense(se_cmd, + TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE, 0); + transport_generic_free_cmd(se_cmd, 0); + } +} + +static void +vhost_scsi_send_bad_target(struct vhost_scsi *vs, + struct vhost_virtqueue *vq, + int head, unsigned out) +{ + struct virtio_scsi_cmd_resp __user *resp; + struct virtio_scsi_cmd_resp rsp; + int ret; + + memset(&rsp, 0, sizeof(rsp)); + rsp.response = VIRTIO_SCSI_S_BAD_TARGET; + resp = vq->iov[out].iov_base; + ret = __copy_to_user(resp, &rsp, sizeof(rsp)); + if (!ret) + vhost_add_used_and_signal(&vs->dev, vq, head, 0); + else + pr_err("Faulted on virtio_scsi_cmd_resp\n"); +} + +static void +vhost_scsi_handle_vq(struct vhost_scsi *vs, struct vhost_virtqueue *vq) +{ + struct tcm_vhost_tpg **vs_tpg; + struct virtio_scsi_cmd_req v_req; + struct virtio_scsi_cmd_req_pi v_req_pi; + struct tcm_vhost_tpg *tpg; + struct tcm_vhost_cmd *cmd; + u64 tag; + u32 exp_data_len, data_first, data_num, data_direction, prot_first; + unsigned out, in, i; + int head, ret, data_niov, prot_niov, prot_bytes; + size_t req_size; + u16 lun; + u8 *target, *lunp, task_attr; + bool hdr_pi; + void *req, *cdb; + + mutex_lock(&vq->mutex); + /* + * We can handle the vq only after the endpoint is setup by calling the + * VHOST_SCSI_SET_ENDPOINT ioctl. + */ + vs_tpg = vq->private_data; + if (!vs_tpg) + goto out; + + vhost_disable_notify(&vs->dev, vq); + + for (;;) { + head = vhost_get_vq_desc(vq, vq->iov, + ARRAY_SIZE(vq->iov), &out, &in, + NULL, NULL); + pr_debug("vhost_get_vq_desc: head: %d, out: %u in: %u\n", + head, out, in); + /* On error, stop handling until the next kick. */ + if (unlikely(head < 0)) + break; + /* Nothing new? Wait for eventfd to tell us they refilled. */ + if (head == vq->num) { + if (unlikely(vhost_enable_notify(&vs->dev, vq))) { + vhost_disable_notify(&vs->dev, vq); + continue; + } + break; + } + + /* FIXME: BIDI operation */ + if (out == 1 && in == 1) { + data_direction = DMA_NONE; + data_first = 0; + data_num = 0; + } else if (out == 1 && in > 1) { + data_direction = DMA_FROM_DEVICE; + data_first = out + 1; + data_num = in - 1; + } else if (out > 1 && in == 1) { + data_direction = DMA_TO_DEVICE; + data_first = 1; + data_num = out - 1; + } else { + vq_err(vq, "Invalid buffer layout out: %u in: %u\n", + out, in); + break; + } + + /* + * Check for a sane resp buffer so we can report errors to + * the guest. + */ + if (unlikely(vq->iov[out].iov_len != + sizeof(struct virtio_scsi_cmd_resp))) { + vq_err(vq, "Expecting virtio_scsi_cmd_resp, got %zu" + " bytes\n", vq->iov[out].iov_len); + break; + } + + if (vhost_has_feature(vq, VIRTIO_SCSI_F_T10_PI)) { + req = &v_req_pi; + lunp = &v_req_pi.lun[0]; + target = &v_req_pi.lun[1]; + req_size = sizeof(v_req_pi); + hdr_pi = true; + } else { + req = &v_req; + lunp = &v_req.lun[0]; + target = &v_req.lun[1]; + req_size = sizeof(v_req); + hdr_pi = false; + } + + if (unlikely(vq->iov[0].iov_len < req_size)) { + pr_err("Expecting virtio-scsi header: %zu, got %zu\n", + req_size, vq->iov[0].iov_len); + break; + } + ret = memcpy_fromiovecend(req, &vq->iov[0], 0, req_size); + if (unlikely(ret)) { + vq_err(vq, "Faulted on virtio_scsi_cmd_req\n"); + break; + } + + /* virtio-scsi spec requires byte 0 of the lun to be 1 */ + if (unlikely(*lunp != 1)) { + vhost_scsi_send_bad_target(vs, vq, head, out); + continue; + } + + tpg = ACCESS_ONCE(vs_tpg[*target]); + + /* Target does not exist, fail the request */ + if (unlikely(!tpg)) { + vhost_scsi_send_bad_target(vs, vq, head, out); + continue; + } + + data_niov = data_num; + prot_niov = prot_first = prot_bytes = 0; + /* + * Determine if any protection information iovecs are preceeding + * the actual data payload, and adjust data_first + data_niov + * values accordingly for vhost_scsi_map_iov_to_sgl() below. + * + * Also extract virtio_scsi header bits for vhost_scsi_get_tag() + */ + if (hdr_pi) { + if (v_req_pi.pi_bytesout) { + if (data_direction != DMA_TO_DEVICE) { + vq_err(vq, "Received non zero do_pi_niov" + ", but wrong data_direction\n"); + goto err_cmd; + } + prot_bytes = v_req_pi.pi_bytesout; + } else if (v_req_pi.pi_bytesin) { + if (data_direction != DMA_FROM_DEVICE) { + vq_err(vq, "Received non zero di_pi_niov" + ", but wrong data_direction\n"); + goto err_cmd; + } + prot_bytes = v_req_pi.pi_bytesin; + } + if (prot_bytes) { + int tmp = 0; + + for (i = 0; i < data_num; i++) { + tmp += vq->iov[data_first + i].iov_len; + prot_niov++; + if (tmp >= prot_bytes) + break; + } + prot_first = data_first; + data_first += prot_niov; + data_niov = data_num - prot_niov; + } + tag = v_req_pi.tag; + task_attr = v_req_pi.task_attr; + cdb = &v_req_pi.cdb[0]; + lun = ((v_req_pi.lun[2] << 8) | v_req_pi.lun[3]) & 0x3FFF; + } else { + tag = v_req.tag; + task_attr = v_req.task_attr; + cdb = &v_req.cdb[0]; + lun = ((v_req.lun[2] << 8) | v_req.lun[3]) & 0x3FFF; + } + exp_data_len = 0; + for (i = 0; i < data_niov; i++) + exp_data_len += vq->iov[data_first + i].iov_len; + /* + * Check that the recieved CDB size does not exceeded our + * hardcoded max for vhost-scsi + * + * TODO what if cdb was too small for varlen cdb header? + */ + if (unlikely(scsi_command_size(cdb) > TCM_VHOST_MAX_CDB_SIZE)) { + vq_err(vq, "Received SCSI CDB with command_size: %d that" + " exceeds SCSI_MAX_VARLEN_CDB_SIZE: %d\n", + scsi_command_size(cdb), TCM_VHOST_MAX_CDB_SIZE); + goto err_cmd; + } + + cmd = vhost_scsi_get_tag(vq, tpg, cdb, tag, lun, task_attr, + exp_data_len + prot_bytes, + data_direction); + if (IS_ERR(cmd)) { + vq_err(vq, "vhost_scsi_get_tag failed %ld\n", + PTR_ERR(cmd)); + goto err_cmd; + } + + pr_debug("Allocated tv_cmd: %p exp_data_len: %d, data_direction" + ": %d\n", cmd, exp_data_len, data_direction); + + cmd->tvc_vhost = vs; + cmd->tvc_vq = vq; + cmd->tvc_resp = vq->iov[out].iov_base; + + pr_debug("vhost_scsi got command opcode: %#02x, lun: %d\n", + cmd->tvc_cdb[0], cmd->tvc_lun); + + if (prot_niov) { + ret = vhost_scsi_map_iov_to_prot(cmd, + &vq->iov[prot_first], prot_niov, + data_direction == DMA_FROM_DEVICE); + if (unlikely(ret)) { + vq_err(vq, "Failed to map iov to" + " prot_sgl\n"); + goto err_free; + } + } + if (data_direction != DMA_NONE) { + ret = vhost_scsi_map_iov_to_sgl(cmd, + &vq->iov[data_first], data_niov, + data_direction == DMA_FROM_DEVICE); + if (unlikely(ret)) { + vq_err(vq, "Failed to map iov to sgl\n"); + goto err_free; + } + } + /* + * Save the descriptor from vhost_get_vq_desc() to be used to + * complete the virtio-scsi request in TCM callback context via + * tcm_vhost_queue_data_in() and tcm_vhost_queue_status() + */ + cmd->tvc_vq_desc = head; + /* + * Dispatch tv_cmd descriptor for cmwq execution in process + * context provided by tcm_vhost_workqueue. This also ensures + * tv_cmd is executed on the same kworker CPU as this vhost + * thread to gain positive L2 cache locality effects.. + */ + INIT_WORK(&cmd->work, tcm_vhost_submission_work); + queue_work(tcm_vhost_workqueue, &cmd->work); + } + + mutex_unlock(&vq->mutex); + return; + +err_free: + vhost_scsi_free_cmd(cmd); +err_cmd: + vhost_scsi_send_bad_target(vs, vq, head, out); +out: + mutex_unlock(&vq->mutex); +} + +static void vhost_scsi_ctl_handle_kick(struct vhost_work *work) +{ + pr_debug("%s: The handling func for control queue.\n", __func__); +} + +static void +tcm_vhost_send_evt(struct vhost_scsi *vs, + struct tcm_vhost_tpg *tpg, + struct se_lun *lun, + u32 event, + u32 reason) +{ + struct tcm_vhost_evt *evt; + + evt = tcm_vhost_allocate_evt(vs, event, reason); + if (!evt) + return; + + if (tpg && lun) { + /* TODO: share lun setup code with virtio-scsi.ko */ + /* + * Note: evt->event is zeroed when we allocate it and + * lun[4-7] need to be zero according to virtio-scsi spec. + */ + evt->event.lun[0] = 0x01; + evt->event.lun[1] = tpg->tport_tpgt & 0xFF; + if (lun->unpacked_lun >= 256) + evt->event.lun[2] = lun->unpacked_lun >> 8 | 0x40 ; + evt->event.lun[3] = lun->unpacked_lun & 0xFF; + } + + llist_add(&evt->list, &vs->vs_event_list); + vhost_work_queue(&vs->dev, &vs->vs_event_work); +} + +static void vhost_scsi_evt_handle_kick(struct vhost_work *work) +{ + struct vhost_virtqueue *vq = container_of(work, struct vhost_virtqueue, + poll.work); + struct vhost_scsi *vs = container_of(vq->dev, struct vhost_scsi, dev); + + mutex_lock(&vq->mutex); + if (!vq->private_data) + goto out; + + if (vs->vs_events_missed) + tcm_vhost_send_evt(vs, NULL, NULL, VIRTIO_SCSI_T_NO_EVENT, 0); +out: + mutex_unlock(&vq->mutex); +} + +static void vhost_scsi_handle_kick(struct vhost_work *work) +{ + struct vhost_virtqueue *vq = container_of(work, struct vhost_virtqueue, + poll.work); + struct vhost_scsi *vs = container_of(vq->dev, struct vhost_scsi, dev); + + vhost_scsi_handle_vq(vs, vq); +} + +static void vhost_scsi_flush_vq(struct vhost_scsi *vs, int index) +{ + vhost_poll_flush(&vs->vqs[index].vq.poll); +} + +/* Callers must hold dev mutex */ +static void vhost_scsi_flush(struct vhost_scsi *vs) +{ + struct vhost_scsi_inflight *old_inflight[VHOST_SCSI_MAX_VQ]; + int i; + + /* Init new inflight and remember the old inflight */ + tcm_vhost_init_inflight(vs, old_inflight); + + /* + * The inflight->kref was initialized to 1. We decrement it here to + * indicate the start of the flush operation so that it will reach 0 + * when all the reqs are finished. + */ + for (i = 0; i < VHOST_SCSI_MAX_VQ; i++) + kref_put(&old_inflight[i]->kref, tcm_vhost_done_inflight); + + /* Flush both the vhost poll and vhost work */ + for (i = 0; i < VHOST_SCSI_MAX_VQ; i++) + vhost_scsi_flush_vq(vs, i); + vhost_work_flush(&vs->dev, &vs->vs_completion_work); + vhost_work_flush(&vs->dev, &vs->vs_event_work); + + /* Wait for all reqs issued before the flush to be finished */ + for (i = 0; i < VHOST_SCSI_MAX_VQ; i++) + wait_for_completion(&old_inflight[i]->comp); +} + +/* + * Called from vhost_scsi_ioctl() context to walk the list of available + * tcm_vhost_tpg with an active struct tcm_vhost_nexus + * + * The lock nesting rule is: + * tcm_vhost_mutex -> vs->dev.mutex -> tpg->tv_tpg_mutex -> vq->mutex + */ +static int +vhost_scsi_set_endpoint(struct vhost_scsi *vs, + struct vhost_scsi_target *t) +{ + struct tcm_vhost_tport *tv_tport; + struct tcm_vhost_tpg *tpg; + struct tcm_vhost_tpg **vs_tpg; + struct vhost_virtqueue *vq; + int index, ret, i, len; + bool match = false; + + mutex_lock(&tcm_vhost_mutex); + mutex_lock(&vs->dev.mutex); + + /* Verify that ring has been setup correctly. */ + for (index = 0; index < vs->dev.nvqs; ++index) { + /* Verify that ring has been setup correctly. */ + if (!vhost_vq_access_ok(&vs->vqs[index].vq)) { + ret = -EFAULT; + goto out; + } + } + + len = sizeof(vs_tpg[0]) * VHOST_SCSI_MAX_TARGET; + vs_tpg = kzalloc(len, GFP_KERNEL); + if (!vs_tpg) { + ret = -ENOMEM; + goto out; + } + if (vs->vs_tpg) + memcpy(vs_tpg, vs->vs_tpg, len); + + list_for_each_entry(tpg, &tcm_vhost_list, tv_tpg_list) { + mutex_lock(&tpg->tv_tpg_mutex); + if (!tpg->tpg_nexus) { + mutex_unlock(&tpg->tv_tpg_mutex); + continue; + } + if (tpg->tv_tpg_vhost_count != 0) { + mutex_unlock(&tpg->tv_tpg_mutex); + continue; + } + tv_tport = tpg->tport; + + if (!strcmp(tv_tport->tport_name, t->vhost_wwpn)) { + if (vs->vs_tpg && vs->vs_tpg[tpg->tport_tpgt]) { + kfree(vs_tpg); + mutex_unlock(&tpg->tv_tpg_mutex); + ret = -EEXIST; + goto out; + } + tpg->tv_tpg_vhost_count++; + tpg->vhost_scsi = vs; + vs_tpg[tpg->tport_tpgt] = tpg; + smp_mb__after_atomic(); + match = true; + } + mutex_unlock(&tpg->tv_tpg_mutex); + } + + if (match) { + memcpy(vs->vs_vhost_wwpn, t->vhost_wwpn, + sizeof(vs->vs_vhost_wwpn)); + for (i = 0; i < VHOST_SCSI_MAX_VQ; i++) { + vq = &vs->vqs[i].vq; + mutex_lock(&vq->mutex); + vq->private_data = vs_tpg; + vhost_init_used(vq); + mutex_unlock(&vq->mutex); + } + ret = 0; + } else { + ret = -EEXIST; + } + + /* + * Act as synchronize_rcu to make sure access to + * old vs->vs_tpg is finished. + */ + vhost_scsi_flush(vs); + kfree(vs->vs_tpg); + vs->vs_tpg = vs_tpg; + +out: + mutex_unlock(&vs->dev.mutex); + mutex_unlock(&tcm_vhost_mutex); + return ret; +} + +static int +vhost_scsi_clear_endpoint(struct vhost_scsi *vs, + struct vhost_scsi_target *t) +{ + struct tcm_vhost_tport *tv_tport; + struct tcm_vhost_tpg *tpg; + struct vhost_virtqueue *vq; + bool match = false; + int index, ret, i; + u8 target; + + mutex_lock(&tcm_vhost_mutex); + mutex_lock(&vs->dev.mutex); + /* Verify that ring has been setup correctly. */ + for (index = 0; index < vs->dev.nvqs; ++index) { + if (!vhost_vq_access_ok(&vs->vqs[index].vq)) { + ret = -EFAULT; + goto err_dev; + } + } + + if (!vs->vs_tpg) { + ret = 0; + goto err_dev; + } + + for (i = 0; i < VHOST_SCSI_MAX_TARGET; i++) { + target = i; + tpg = vs->vs_tpg[target]; + if (!tpg) + continue; + + mutex_lock(&tpg->tv_tpg_mutex); + tv_tport = tpg->tport; + if (!tv_tport) { + ret = -ENODEV; + goto err_tpg; + } + + if (strcmp(tv_tport->tport_name, t->vhost_wwpn)) { + pr_warn("tv_tport->tport_name: %s, tpg->tport_tpgt: %hu" + " does not match t->vhost_wwpn: %s, t->vhost_tpgt: %hu\n", + tv_tport->tport_name, tpg->tport_tpgt, + t->vhost_wwpn, t->vhost_tpgt); + ret = -EINVAL; + goto err_tpg; + } + tpg->tv_tpg_vhost_count--; + tpg->vhost_scsi = NULL; + vs->vs_tpg[target] = NULL; + match = true; + mutex_unlock(&tpg->tv_tpg_mutex); + } + if (match) { + for (i = 0; i < VHOST_SCSI_MAX_VQ; i++) { + vq = &vs->vqs[i].vq; + mutex_lock(&vq->mutex); + vq->private_data = NULL; + mutex_unlock(&vq->mutex); + } + } + /* + * Act as synchronize_rcu to make sure access to + * old vs->vs_tpg is finished. + */ + vhost_scsi_flush(vs); + kfree(vs->vs_tpg); + vs->vs_tpg = NULL; + WARN_ON(vs->vs_events_nr); + mutex_unlock(&vs->dev.mutex); + mutex_unlock(&tcm_vhost_mutex); + return 0; + +err_tpg: + mutex_unlock(&tpg->tv_tpg_mutex); +err_dev: + mutex_unlock(&vs->dev.mutex); + mutex_unlock(&tcm_vhost_mutex); + return ret; +} + +static int vhost_scsi_set_features(struct vhost_scsi *vs, u64 features) +{ + struct vhost_virtqueue *vq; + int i; + + if (features & ~VHOST_SCSI_FEATURES) + return -EOPNOTSUPP; + + mutex_lock(&vs->dev.mutex); + if ((features & (1 << VHOST_F_LOG_ALL)) && + !vhost_log_access_ok(&vs->dev)) { + mutex_unlock(&vs->dev.mutex); + return -EFAULT; + } + + for (i = 0; i < VHOST_SCSI_MAX_VQ; i++) { + vq = &vs->vqs[i].vq; + mutex_lock(&vq->mutex); + vq->acked_features = features; + mutex_unlock(&vq->mutex); + } + mutex_unlock(&vs->dev.mutex); + return 0; +} + +static int vhost_scsi_open(struct inode *inode, struct file *f) +{ + struct vhost_scsi *vs; + struct vhost_virtqueue **vqs; + int r = -ENOMEM, i; + + vs = kzalloc(sizeof(*vs), GFP_KERNEL | __GFP_NOWARN | __GFP_REPEAT); + if (!vs) { + vs = vzalloc(sizeof(*vs)); + if (!vs) + goto err_vs; + } + + vqs = kmalloc(VHOST_SCSI_MAX_VQ * sizeof(*vqs), GFP_KERNEL); + if (!vqs) + goto err_vqs; + + vhost_work_init(&vs->vs_completion_work, vhost_scsi_complete_cmd_work); + vhost_work_init(&vs->vs_event_work, tcm_vhost_evt_work); + + vs->vs_events_nr = 0; + vs->vs_events_missed = false; + + vqs[VHOST_SCSI_VQ_CTL] = &vs->vqs[VHOST_SCSI_VQ_CTL].vq; + vqs[VHOST_SCSI_VQ_EVT] = &vs->vqs[VHOST_SCSI_VQ_EVT].vq; + vs->vqs[VHOST_SCSI_VQ_CTL].vq.handle_kick = vhost_scsi_ctl_handle_kick; + vs->vqs[VHOST_SCSI_VQ_EVT].vq.handle_kick = vhost_scsi_evt_handle_kick; + for (i = VHOST_SCSI_VQ_IO; i < VHOST_SCSI_MAX_VQ; i++) { + vqs[i] = &vs->vqs[i].vq; + vs->vqs[i].vq.handle_kick = vhost_scsi_handle_kick; + } + vhost_dev_init(&vs->dev, vqs, VHOST_SCSI_MAX_VQ); + + tcm_vhost_init_inflight(vs, NULL); + + f->private_data = vs; + return 0; + +err_vqs: + kvfree(vs); +err_vs: + return r; +} + +static int vhost_scsi_release(struct inode *inode, struct file *f) +{ + struct vhost_scsi *vs = f->private_data; + struct vhost_scsi_target t; + + mutex_lock(&vs->dev.mutex); + memcpy(t.vhost_wwpn, vs->vs_vhost_wwpn, sizeof(t.vhost_wwpn)); + mutex_unlock(&vs->dev.mutex); + vhost_scsi_clear_endpoint(vs, &t); + vhost_dev_stop(&vs->dev); + vhost_dev_cleanup(&vs->dev, false); + /* Jobs can re-queue themselves in evt kick handler. Do extra flush. */ + vhost_scsi_flush(vs); + kfree(vs->dev.vqs); + kvfree(vs); + return 0; +} + +static long +vhost_scsi_ioctl(struct file *f, + unsigned int ioctl, + unsigned long arg) +{ + struct vhost_scsi *vs = f->private_data; + struct vhost_scsi_target backend; + void __user *argp = (void __user *)arg; + u64 __user *featurep = argp; + u32 __user *eventsp = argp; + u32 events_missed; + u64 features; + int r, abi_version = VHOST_SCSI_ABI_VERSION; + struct vhost_virtqueue *vq = &vs->vqs[VHOST_SCSI_VQ_EVT].vq; + + switch (ioctl) { + case VHOST_SCSI_SET_ENDPOINT: + if (copy_from_user(&backend, argp, sizeof backend)) + return -EFAULT; + if (backend.reserved != 0) + return -EOPNOTSUPP; + + return vhost_scsi_set_endpoint(vs, &backend); + case VHOST_SCSI_CLEAR_ENDPOINT: + if (copy_from_user(&backend, argp, sizeof backend)) + return -EFAULT; + if (backend.reserved != 0) + return -EOPNOTSUPP; + + return vhost_scsi_clear_endpoint(vs, &backend); + case VHOST_SCSI_GET_ABI_VERSION: + if (copy_to_user(argp, &abi_version, sizeof abi_version)) + return -EFAULT; + return 0; + case VHOST_SCSI_SET_EVENTS_MISSED: + if (get_user(events_missed, eventsp)) + return -EFAULT; + mutex_lock(&vq->mutex); + vs->vs_events_missed = events_missed; + mutex_unlock(&vq->mutex); + return 0; + case VHOST_SCSI_GET_EVENTS_MISSED: + mutex_lock(&vq->mutex); + events_missed = vs->vs_events_missed; + mutex_unlock(&vq->mutex); + if (put_user(events_missed, eventsp)) + return -EFAULT; + return 0; + case VHOST_GET_FEATURES: + features = VHOST_SCSI_FEATURES; + if (copy_to_user(featurep, &features, sizeof features)) + return -EFAULT; + return 0; + case VHOST_SET_FEATURES: + if (copy_from_user(&features, featurep, sizeof features)) + return -EFAULT; + return vhost_scsi_set_features(vs, features); + default: + mutex_lock(&vs->dev.mutex); + r = vhost_dev_ioctl(&vs->dev, ioctl, argp); + /* TODO: flush backend after dev ioctl. */ + if (r == -ENOIOCTLCMD) + r = vhost_vring_ioctl(&vs->dev, ioctl, argp); + mutex_unlock(&vs->dev.mutex); + return r; + } +} + +#ifdef CONFIG_COMPAT +static long vhost_scsi_compat_ioctl(struct file *f, unsigned int ioctl, + unsigned long arg) +{ + return vhost_scsi_ioctl(f, ioctl, (unsigned long)compat_ptr(arg)); +} +#endif + +static const struct file_operations vhost_scsi_fops = { + .owner = THIS_MODULE, + .release = vhost_scsi_release, + .unlocked_ioctl = vhost_scsi_ioctl, +#ifdef CONFIG_COMPAT + .compat_ioctl = vhost_scsi_compat_ioctl, +#endif + .open = vhost_scsi_open, + .llseek = noop_llseek, +}; + +static struct miscdevice vhost_scsi_misc = { + MISC_DYNAMIC_MINOR, + "vhost-scsi", + &vhost_scsi_fops, +}; + +static int __init vhost_scsi_register(void) +{ + return misc_register(&vhost_scsi_misc); +} + +static int vhost_scsi_deregister(void) +{ + return misc_deregister(&vhost_scsi_misc); +} + +static char *tcm_vhost_dump_proto_id(struct tcm_vhost_tport *tport) +{ + switch (tport->tport_proto_id) { + case SCSI_PROTOCOL_SAS: + return "SAS"; + case SCSI_PROTOCOL_FCP: + return "FCP"; + case SCSI_PROTOCOL_ISCSI: + return "iSCSI"; + default: + break; + } + + return "Unknown"; +} + +static void +tcm_vhost_do_plug(struct tcm_vhost_tpg *tpg, + struct se_lun *lun, bool plug) +{ + + struct vhost_scsi *vs = tpg->vhost_scsi; + struct vhost_virtqueue *vq; + u32 reason; + + if (!vs) + return; + + mutex_lock(&vs->dev.mutex); + + if (plug) + reason = VIRTIO_SCSI_EVT_RESET_RESCAN; + else + reason = VIRTIO_SCSI_EVT_RESET_REMOVED; + + vq = &vs->vqs[VHOST_SCSI_VQ_EVT].vq; + mutex_lock(&vq->mutex); + if (vhost_has_feature(vq, VIRTIO_SCSI_F_HOTPLUG)) + tcm_vhost_send_evt(vs, tpg, lun, + VIRTIO_SCSI_T_TRANSPORT_RESET, reason); + mutex_unlock(&vq->mutex); + mutex_unlock(&vs->dev.mutex); +} + +static void tcm_vhost_hotplug(struct tcm_vhost_tpg *tpg, struct se_lun *lun) +{ + tcm_vhost_do_plug(tpg, lun, true); +} + +static void tcm_vhost_hotunplug(struct tcm_vhost_tpg *tpg, struct se_lun *lun) +{ + tcm_vhost_do_plug(tpg, lun, false); +} + +static int tcm_vhost_port_link(struct se_portal_group *se_tpg, + struct se_lun *lun) +{ + struct tcm_vhost_tpg *tpg = container_of(se_tpg, + struct tcm_vhost_tpg, se_tpg); + + mutex_lock(&tcm_vhost_mutex); + + mutex_lock(&tpg->tv_tpg_mutex); + tpg->tv_tpg_port_count++; + mutex_unlock(&tpg->tv_tpg_mutex); + + tcm_vhost_hotplug(tpg, lun); + + mutex_unlock(&tcm_vhost_mutex); + + return 0; +} + +static void tcm_vhost_port_unlink(struct se_portal_group *se_tpg, + struct se_lun *lun) +{ + struct tcm_vhost_tpg *tpg = container_of(se_tpg, + struct tcm_vhost_tpg, se_tpg); + + mutex_lock(&tcm_vhost_mutex); + + mutex_lock(&tpg->tv_tpg_mutex); + tpg->tv_tpg_port_count--; + mutex_unlock(&tpg->tv_tpg_mutex); + + tcm_vhost_hotunplug(tpg, lun); + + mutex_unlock(&tcm_vhost_mutex); +} + +static struct se_node_acl * +tcm_vhost_make_nodeacl(struct se_portal_group *se_tpg, + struct config_group *group, + const char *name) +{ + struct se_node_acl *se_nacl, *se_nacl_new; + struct tcm_vhost_nacl *nacl; + u64 wwpn = 0; + u32 nexus_depth; + + /* tcm_vhost_parse_wwn(name, &wwpn, 1) < 0) + return ERR_PTR(-EINVAL); */ + se_nacl_new = tcm_vhost_alloc_fabric_acl(se_tpg); + if (!se_nacl_new) + return ERR_PTR(-ENOMEM); + + nexus_depth = 1; + /* + * se_nacl_new may be released by core_tpg_add_initiator_node_acl() + * when converting a NodeACL from demo mode -> explict + */ + se_nacl = core_tpg_add_initiator_node_acl(se_tpg, se_nacl_new, + name, nexus_depth); + if (IS_ERR(se_nacl)) { + tcm_vhost_release_fabric_acl(se_tpg, se_nacl_new); + return se_nacl; + } + /* + * Locate our struct tcm_vhost_nacl and set the FC Nport WWPN + */ + nacl = container_of(se_nacl, struct tcm_vhost_nacl, se_node_acl); + nacl->iport_wwpn = wwpn; + + return se_nacl; +} + +static void tcm_vhost_drop_nodeacl(struct se_node_acl *se_acl) +{ + struct tcm_vhost_nacl *nacl = container_of(se_acl, + struct tcm_vhost_nacl, se_node_acl); + core_tpg_del_initiator_node_acl(se_acl->se_tpg, se_acl, 1); + kfree(nacl); +} + +static void tcm_vhost_free_cmd_map_res(struct tcm_vhost_nexus *nexus, + struct se_session *se_sess) +{ + struct tcm_vhost_cmd *tv_cmd; + unsigned int i; + + if (!se_sess->sess_cmd_map) + return; + + for (i = 0; i < TCM_VHOST_DEFAULT_TAGS; i++) { + tv_cmd = &((struct tcm_vhost_cmd *)se_sess->sess_cmd_map)[i]; + + kfree(tv_cmd->tvc_sgl); + kfree(tv_cmd->tvc_prot_sgl); + kfree(tv_cmd->tvc_upages); + } +} + +static int tcm_vhost_make_nexus(struct tcm_vhost_tpg *tpg, + const char *name) +{ + struct se_portal_group *se_tpg; + struct se_session *se_sess; + struct tcm_vhost_nexus *tv_nexus; + struct tcm_vhost_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 tcm_vhost_nexus), GFP_KERNEL); + if (!tv_nexus) { + mutex_unlock(&tpg->tv_tpg_mutex); + pr_err("Unable to allocate struct tcm_vhost_nexus\n"); + return -ENOMEM; + } + /* + * Initialize the struct se_session pointer and setup tagpool + * for struct tcm_vhost_cmd descriptors + */ + tv_nexus->tvn_se_sess = transport_init_session_tags( + TCM_VHOST_DEFAULT_TAGS, + sizeof(struct tcm_vhost_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 < TCM_VHOST_DEFAULT_TAGS; i++) { + tv_cmd = &((struct tcm_vhost_cmd *)se_sess->sess_cmd_map)[i]; + + tv_cmd->tvc_sgl = kzalloc(sizeof(struct scatterlist) * + TCM_VHOST_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 *) * + TCM_VHOST_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) * + TCM_VHOST_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; + } + } + /* + * Since we are running in 'demo mode' this call with generate a + * struct se_node_acl for the tcm_vhost 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) { + mutex_unlock(&tpg->tv_tpg_mutex); + pr_debug("core_tpg_check_initiator_node_acl() failed" + " for %s\n", name); + goto out; + } + /* + * Now register the TCM vhost virtual I_T Nexus as active with the + * call to __transport_register_session() + */ + __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: + tcm_vhost_free_cmd_map_res(tv_nexus, se_sess); + transport_free_session(se_sess); + kfree(tv_nexus); + return -ENOMEM; +} + +static int tcm_vhost_drop_nexus(struct tcm_vhost_tpg *tpg) +{ + struct se_session *se_sess; + struct tcm_vhost_nexus *tv_nexus; + + mutex_lock(&tpg->tv_tpg_mutex); + tv_nexus = tpg->tpg_nexus; + if (!tv_nexus) { + mutex_unlock(&tpg->tv_tpg_mutex); + return -ENODEV; + } + + se_sess = tv_nexus->tvn_se_sess; + if (!se_sess) { + mutex_unlock(&tpg->tv_tpg_mutex); + return -ENODEV; + } + + if (tpg->tv_tpg_port_count != 0) { + mutex_unlock(&tpg->tv_tpg_mutex); + pr_err("Unable to remove TCM_vhost I_T Nexus with" + " active TPG port count: %d\n", + tpg->tv_tpg_port_count); + return -EBUSY; + } + + if (tpg->tv_tpg_vhost_count != 0) { + mutex_unlock(&tpg->tv_tpg_mutex); + pr_err("Unable to remove TCM_vhost I_T Nexus with" + " active TPG vhost count: %d\n", + tpg->tv_tpg_vhost_count); + return -EBUSY; + } + + pr_debug("TCM_vhost_ConfigFS: Removing I_T Nexus to emulated" + " %s Initiator Port: %s\n", tcm_vhost_dump_proto_id(tpg->tport), + tv_nexus->tvn_se_sess->se_node_acl->initiatorname); + + tcm_vhost_free_cmd_map_res(tv_nexus, se_sess); + /* + * Release the SCSI I_T Nexus to the emulated vhost Target Port + */ + transport_deregister_session(tv_nexus->tvn_se_sess); + tpg->tpg_nexus = NULL; + mutex_unlock(&tpg->tv_tpg_mutex); + + kfree(tv_nexus); + return 0; +} + +static ssize_t tcm_vhost_tpg_show_nexus(struct se_portal_group *se_tpg, + char *page) +{ + struct tcm_vhost_tpg *tpg = container_of(se_tpg, + struct tcm_vhost_tpg, se_tpg); + struct tcm_vhost_nexus *tv_nexus; + ssize_t ret; + + mutex_lock(&tpg->tv_tpg_mutex); + tv_nexus = tpg->tpg_nexus; + if (!tv_nexus) { + mutex_unlock(&tpg->tv_tpg_mutex); + return -ENODEV; + } + ret = snprintf(page, PAGE_SIZE, "%s\n", + tv_nexus->tvn_se_sess->se_node_acl->initiatorname); + mutex_unlock(&tpg->tv_tpg_mutex); + + return ret; +} + +static ssize_t tcm_vhost_tpg_store_nexus(struct se_portal_group *se_tpg, + const char *page, + size_t count) +{ + struct tcm_vhost_tpg *tpg = container_of(se_tpg, + struct tcm_vhost_tpg, se_tpg); + struct tcm_vhost_tport *tport_wwn = tpg->tport; + unsigned char i_port[TCM_VHOST_NAMELEN], *ptr, *port_ptr; + int ret; + /* + * Shutdown the active I_T nexus if 'NULL' is passed.. + */ + if (!strncmp(page, "NULL", 4)) { + ret = tcm_vhost_drop_nexus(tpg); + return (!ret) ? count : ret; + } + /* + * Otherwise make sure the passed virtual Initiator port WWN matches + * the fabric protocol_id set in tcm_vhost_make_tport(), and call + * tcm_vhost_make_nexus(). + */ + if (strlen(page) >= TCM_VHOST_NAMELEN) { + pr_err("Emulated NAA Sas Address: %s, exceeds" + " max: %d\n", page, TCM_VHOST_NAMELEN); + return -EINVAL; + } + snprintf(&i_port[0], TCM_VHOST_NAMELEN, "%s", page); + + ptr = strstr(i_port, "naa."); + if (ptr) { + if (tport_wwn->tport_proto_id != SCSI_PROTOCOL_SAS) { + pr_err("Passed SAS Initiator Port %s does not" + " match target port protoid: %s\n", i_port, + tcm_vhost_dump_proto_id(tport_wwn)); + return -EINVAL; + } + port_ptr = &i_port[0]; + goto check_newline; + } + ptr = strstr(i_port, "fc."); + if (ptr) { + if (tport_wwn->tport_proto_id != SCSI_PROTOCOL_FCP) { + pr_err("Passed FCP Initiator Port %s does not" + " match target port protoid: %s\n", i_port, + tcm_vhost_dump_proto_id(tport_wwn)); + return -EINVAL; + } + port_ptr = &i_port[3]; /* Skip over "fc." */ + goto check_newline; + } + ptr = strstr(i_port, "iqn."); + if (ptr) { + if (tport_wwn->tport_proto_id != SCSI_PROTOCOL_ISCSI) { + pr_err("Passed iSCSI Initiator Port %s does not" + " match target port protoid: %s\n", i_port, + tcm_vhost_dump_proto_id(tport_wwn)); + return -EINVAL; + } + port_ptr = &i_port[0]; + goto check_newline; + } + pr_err("Unable to locate prefix for emulated Initiator Port:" + " %s\n", i_port); + return -EINVAL; + /* + * Clear any trailing newline for the NAA WWN + */ +check_newline: + if (i_port[strlen(i_port)-1] == '\n') + i_port[strlen(i_port)-1] = '\0'; + + ret = tcm_vhost_make_nexus(tpg, port_ptr); + if (ret < 0) + return ret; + + return count; +} + +TF_TPG_BASE_ATTR(tcm_vhost, nexus, S_IRUGO | S_IWUSR); + +static struct configfs_attribute *tcm_vhost_tpg_attrs[] = { + &tcm_vhost_tpg_nexus.attr, + NULL, +}; + +static struct se_portal_group * +tcm_vhost_make_tpg(struct se_wwn *wwn, + struct config_group *group, + const char *name) +{ + struct tcm_vhost_tport *tport = container_of(wwn, + struct tcm_vhost_tport, tport_wwn); + + struct tcm_vhost_tpg *tpg; + unsigned long tpgt; + int ret; + + if (strstr(name, "tpgt_") != name) + return ERR_PTR(-EINVAL); + if (kstrtoul(name + 5, 10, &tpgt) || tpgt > UINT_MAX) + return ERR_PTR(-EINVAL); + + tpg = kzalloc(sizeof(struct tcm_vhost_tpg), GFP_KERNEL); + if (!tpg) { + pr_err("Unable to allocate struct tcm_vhost_tpg"); + return ERR_PTR(-ENOMEM); + } + mutex_init(&tpg->tv_tpg_mutex); + INIT_LIST_HEAD(&tpg->tv_tpg_list); + tpg->tport = tport; + tpg->tport_tpgt = tpgt; + + ret = core_tpg_register(&tcm_vhost_fabric_configfs->tf_ops, wwn, + &tpg->se_tpg, tpg, TRANSPORT_TPG_TYPE_NORMAL); + if (ret < 0) { + kfree(tpg); + return NULL; + } + mutex_lock(&tcm_vhost_mutex); + list_add_tail(&tpg->tv_tpg_list, &tcm_vhost_list); + mutex_unlock(&tcm_vhost_mutex); + + return &tpg->se_tpg; +} + +static void tcm_vhost_drop_tpg(struct se_portal_group *se_tpg) +{ + struct tcm_vhost_tpg *tpg = container_of(se_tpg, + struct tcm_vhost_tpg, se_tpg); + + mutex_lock(&tcm_vhost_mutex); + list_del(&tpg->tv_tpg_list); + mutex_unlock(&tcm_vhost_mutex); + /* + * Release the virtual I_T Nexus for this vhost TPG + */ + tcm_vhost_drop_nexus(tpg); + /* + * Deregister the se_tpg from TCM.. + */ + core_tpg_deregister(se_tpg); + kfree(tpg); +} + +static struct se_wwn * +tcm_vhost_make_tport(struct target_fabric_configfs *tf, + struct config_group *group, + const char *name) +{ + struct tcm_vhost_tport *tport; + char *ptr; + u64 wwpn = 0; + int off = 0; + + /* if (tcm_vhost_parse_wwn(name, &wwpn, 1) < 0) + return ERR_PTR(-EINVAL); */ + + tport = kzalloc(sizeof(struct tcm_vhost_tport), GFP_KERNEL); + if (!tport) { + pr_err("Unable to allocate struct tcm_vhost_tport"); + return ERR_PTR(-ENOMEM); + } + tport->tport_wwpn = wwpn; + /* + * Determine the emulated Protocol Identifier and Target Port Name + * based on the incoming configfs directory name. + */ + ptr = strstr(name, "naa."); + if (ptr) { + tport->tport_proto_id = SCSI_PROTOCOL_SAS; + goto check_len; + } + ptr = strstr(name, "fc."); + if (ptr) { + tport->tport_proto_id = SCSI_PROTOCOL_FCP; + off = 3; /* Skip over "fc." */ + goto check_len; + } + ptr = strstr(name, "iqn."); + if (ptr) { + tport->tport_proto_id = SCSI_PROTOCOL_ISCSI; + goto check_len; + } + + pr_err("Unable to locate prefix for emulated Target Port:" + " %s\n", name); + kfree(tport); + return ERR_PTR(-EINVAL); + +check_len: + if (strlen(name) >= TCM_VHOST_NAMELEN) { + pr_err("Emulated %s Address: %s, exceeds" + " max: %d\n", name, tcm_vhost_dump_proto_id(tport), + TCM_VHOST_NAMELEN); + kfree(tport); + return ERR_PTR(-EINVAL); + } + snprintf(&tport->tport_name[0], TCM_VHOST_NAMELEN, "%s", &name[off]); + + pr_debug("TCM_VHost_ConfigFS: Allocated emulated Target" + " %s Address: %s\n", tcm_vhost_dump_proto_id(tport), name); + + return &tport->tport_wwn; +} + +static void tcm_vhost_drop_tport(struct se_wwn *wwn) +{ + struct tcm_vhost_tport *tport = container_of(wwn, + struct tcm_vhost_tport, tport_wwn); + + pr_debug("TCM_VHost_ConfigFS: Deallocating emulated Target" + " %s Address: %s\n", tcm_vhost_dump_proto_id(tport), + tport->tport_name); + + kfree(tport); +} + +static ssize_t +tcm_vhost_wwn_show_attr_version(struct target_fabric_configfs *tf, + char *page) +{ + return sprintf(page, "TCM_VHOST fabric module %s on %s/%s" + "on "UTS_RELEASE"\n", TCM_VHOST_VERSION, utsname()->sysname, + utsname()->machine); +} + +TF_WWN_ATTR_RO(tcm_vhost, version); + +static struct configfs_attribute *tcm_vhost_wwn_attrs[] = { + &tcm_vhost_wwn_version.attr, + NULL, +}; + +static struct target_core_fabric_ops tcm_vhost_ops = { + .get_fabric_name = tcm_vhost_get_fabric_name, + .get_fabric_proto_ident = tcm_vhost_get_fabric_proto_ident, + .tpg_get_wwn = tcm_vhost_get_fabric_wwn, + .tpg_get_tag = tcm_vhost_get_tag, + .tpg_get_default_depth = tcm_vhost_get_default_depth, + .tpg_get_pr_transport_id = tcm_vhost_get_pr_transport_id, + .tpg_get_pr_transport_id_len = tcm_vhost_get_pr_transport_id_len, + .tpg_parse_pr_out_transport_id = tcm_vhost_parse_pr_out_transport_id, + .tpg_check_demo_mode = tcm_vhost_check_true, + .tpg_check_demo_mode_cache = tcm_vhost_check_true, + .tpg_check_demo_mode_write_protect = tcm_vhost_check_false, + .tpg_check_prod_mode_write_protect = tcm_vhost_check_false, + .tpg_alloc_fabric_acl = tcm_vhost_alloc_fabric_acl, + .tpg_release_fabric_acl = tcm_vhost_release_fabric_acl, + .tpg_get_inst_index = tcm_vhost_tpg_get_inst_index, + .release_cmd = tcm_vhost_release_cmd, + .check_stop_free = vhost_scsi_check_stop_free, + .shutdown_session = tcm_vhost_shutdown_session, + .close_session = tcm_vhost_close_session, + .sess_get_index = tcm_vhost_sess_get_index, + .sess_get_initiator_sid = NULL, + .write_pending = tcm_vhost_write_pending, + .write_pending_status = tcm_vhost_write_pending_status, + .set_default_node_attributes = tcm_vhost_set_default_node_attrs, + .get_task_tag = tcm_vhost_get_task_tag, + .get_cmd_state = tcm_vhost_get_cmd_state, + .queue_data_in = tcm_vhost_queue_data_in, + .queue_status = tcm_vhost_queue_status, + .queue_tm_rsp = tcm_vhost_queue_tm_rsp, + .aborted_task = tcm_vhost_aborted_task, + /* + * Setup callers for generic logic in target_core_fabric_configfs.c + */ + .fabric_make_wwn = tcm_vhost_make_tport, + .fabric_drop_wwn = tcm_vhost_drop_tport, + .fabric_make_tpg = tcm_vhost_make_tpg, + .fabric_drop_tpg = tcm_vhost_drop_tpg, + .fabric_post_link = tcm_vhost_port_link, + .fabric_pre_unlink = tcm_vhost_port_unlink, + .fabric_make_np = NULL, + .fabric_drop_np = NULL, + .fabric_make_nodeacl = tcm_vhost_make_nodeacl, + .fabric_drop_nodeacl = tcm_vhost_drop_nodeacl, +}; + +static int tcm_vhost_register_configfs(void) +{ + struct target_fabric_configfs *fabric; + int ret; + + pr_debug("TCM_VHOST fabric module %s on %s/%s" + " on "UTS_RELEASE"\n", TCM_VHOST_VERSION, utsname()->sysname, + utsname()->machine); + /* + * Register the top level struct config_item_type with TCM core + */ + fabric = target_fabric_configfs_init(THIS_MODULE, "vhost"); + if (IS_ERR(fabric)) { + pr_err("target_fabric_configfs_init() failed\n"); + return PTR_ERR(fabric); + } + /* + * Setup fabric->tf_ops from our local tcm_vhost_ops + */ + fabric->tf_ops = tcm_vhost_ops; + /* + * Setup default attribute lists for various fabric->tf_cit_tmpl + */ + fabric->tf_cit_tmpl.tfc_wwn_cit.ct_attrs = tcm_vhost_wwn_attrs; + fabric->tf_cit_tmpl.tfc_tpg_base_cit.ct_attrs = tcm_vhost_tpg_attrs; + fabric->tf_cit_tmpl.tfc_tpg_attrib_cit.ct_attrs = NULL; + fabric->tf_cit_tmpl.tfc_tpg_param_cit.ct_attrs = NULL; + fabric->tf_cit_tmpl.tfc_tpg_np_base_cit.ct_attrs = NULL; + fabric->tf_cit_tmpl.tfc_tpg_nacl_base_cit.ct_attrs = NULL; + fabric->tf_cit_tmpl.tfc_tpg_nacl_attrib_cit.ct_attrs = NULL; + fabric->tf_cit_tmpl.tfc_tpg_nacl_auth_cit.ct_attrs = NULL; + fabric->tf_cit_tmpl.tfc_tpg_nacl_param_cit.ct_attrs = NULL; + /* + * Register the fabric for use within TCM + */ + ret = target_fabric_configfs_register(fabric); + if (ret < 0) { + pr_err("target_fabric_configfs_register() failed" + " for TCM_VHOST\n"); + return ret; + } + /* + * Setup our local pointer to *fabric + */ + tcm_vhost_fabric_configfs = fabric; + pr_debug("TCM_VHOST[0] - Set fabric -> tcm_vhost_fabric_configfs\n"); + return 0; +}; + +static void tcm_vhost_deregister_configfs(void) +{ + if (!tcm_vhost_fabric_configfs) + return; + + target_fabric_configfs_deregister(tcm_vhost_fabric_configfs); + tcm_vhost_fabric_configfs = NULL; + pr_debug("TCM_VHOST[0] - Cleared tcm_vhost_fabric_configfs\n"); +}; + +static int __init tcm_vhost_init(void) +{ + int ret = -ENOMEM; + /* + * Use our own dedicated workqueue for submitting I/O into + * target core to avoid contention within system_wq. + */ + tcm_vhost_workqueue = alloc_workqueue("tcm_vhost", 0, 0); + if (!tcm_vhost_workqueue) + goto out; + + ret = vhost_scsi_register(); + if (ret < 0) + goto out_destroy_workqueue; + + ret = tcm_vhost_register_configfs(); + if (ret < 0) + goto out_vhost_scsi_deregister; + + return 0; + +out_vhost_scsi_deregister: + vhost_scsi_deregister(); +out_destroy_workqueue: + destroy_workqueue(tcm_vhost_workqueue); +out: + return ret; +}; + +static void tcm_vhost_exit(void) +{ + tcm_vhost_deregister_configfs(); + vhost_scsi_deregister(); + destroy_workqueue(tcm_vhost_workqueue); +}; + +MODULE_DESCRIPTION("VHOST_SCSI series fabric driver"); +MODULE_ALIAS("tcm_vhost"); +MODULE_LICENSE("GPL"); +module_init(tcm_vhost_init); +module_exit(tcm_vhost_exit); diff --git a/drivers/vhost/tcm_vhost.c b/drivers/vhost/tcm_vhost.c deleted file mode 100644 index b20df5c829f..00000000000 --- a/drivers/vhost/tcm_vhost.c +++ /dev/null @@ -1,1593 +0,0 @@ -/******************************************************************************* - * Vhost kernel TCM fabric driver for virtio SCSI initiators - * - * (C) Copyright 2010-2012 RisingTide Systems LLC. - * (C) Copyright 2010-2012 IBM Corp. - * - * Licensed to the Linux Foundation under the General Public License (GPL) version 2. - * - * Authors: Nicholas A. Bellinger <nab@risingtidesystems.com> - * Stefan Hajnoczi <stefanha@linux.vnet.ibm.com> - * - * This program is free software; you can redistribute it and/or modify - * it under the terms of the GNU General Public License as published by - * the Free Software Foundation; either version 2 of the License, or - * (at your option) any later version. - * - * This program is distributed in the hope that it will be useful, - * but WITHOUT ANY WARRANTY; without even the implied warranty of - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the - * GNU General Public License for more details. - * - ****************************************************************************/ - -#include <linux/module.h> -#include <linux/moduleparam.h> -#include <generated/utsrelease.h> -#include <linux/utsname.h> -#include <linux/init.h> -#include <linux/slab.h> -#include <linux/kthread.h> -#include <linux/types.h> -#include <linux/string.h> -#include <linux/configfs.h> -#include <linux/ctype.h> -#include <linux/compat.h> -#include <linux/eventfd.h> -#include <linux/fs.h> -#include <linux/miscdevice.h> -#include <asm/unaligned.h> -#include <scsi/scsi.h> -#include <scsi/scsi_tcq.h> -#include <target/target_core_base.h> -#include <target/target_core_fabric.h> -#include <target/target_core_fabric_configfs.h> -#include <target/target_core_configfs.h> -#include <target/configfs_macros.h> -#include <linux/vhost.h> -#include <linux/virtio_net.h> /* TODO vhost.h currently depends on this */ -#include <linux/virtio_scsi.h> - -#include "vhost.c" -#include "vhost.h" -#include "tcm_vhost.h" - -enum { - VHOST_SCSI_VQ_CTL = 0, - VHOST_SCSI_VQ_EVT = 1, - VHOST_SCSI_VQ_IO = 2, -}; - -struct vhost_scsi { - struct tcm_vhost_tpg *vs_tpg; /* Protected by vhost_scsi->dev.mutex */ - struct vhost_dev dev; - struct vhost_virtqueue vqs[3]; - - struct vhost_work vs_completion_work; /* cmd completion work item */ - struct list_head vs_completion_list; /* cmd completion queue */ - spinlock_t vs_completion_lock; /* protects s_completion_list */ -}; - -/* Local pointer to allocated TCM configfs fabric module */ -static struct target_fabric_configfs *tcm_vhost_fabric_configfs; - -static struct workqueue_struct *tcm_vhost_workqueue; - -/* Global spinlock to protect tcm_vhost TPG list for vhost IOCTL access */ -static DEFINE_MUTEX(tcm_vhost_mutex); -static LIST_HEAD(tcm_vhost_list); - -static int tcm_vhost_check_true(struct se_portal_group *se_tpg) -{ - return 1; -} - -static int tcm_vhost_check_false(struct se_portal_group *se_tpg) -{ - return 0; -} - -static char *tcm_vhost_get_fabric_name(void) -{ - return "vhost"; -} - -static u8 tcm_vhost_get_fabric_proto_ident(struct se_portal_group *se_tpg) -{ - struct tcm_vhost_tpg *tpg = container_of(se_tpg, - struct tcm_vhost_tpg, se_tpg); - struct tcm_vhost_tport *tport = tpg->tport; - - switch (tport->tport_proto_id) { - case SCSI_PROTOCOL_SAS: - return sas_get_fabric_proto_ident(se_tpg); - case SCSI_PROTOCOL_FCP: - return fc_get_fabric_proto_ident(se_tpg); - case SCSI_PROTOCOL_ISCSI: - return iscsi_get_fabric_proto_ident(se_tpg); - default: - pr_err("Unknown tport_proto_id: 0x%02x, using" - " SAS emulation\n", tport->tport_proto_id); - break; - } - - return sas_get_fabric_proto_ident(se_tpg); -} - -static char *tcm_vhost_get_fabric_wwn(struct se_portal_group *se_tpg) -{ - struct tcm_vhost_tpg *tpg = container_of(se_tpg, - struct tcm_vhost_tpg, se_tpg); - struct tcm_vhost_tport *tport = tpg->tport; - - return &tport->tport_name[0]; -} - -static u16 tcm_vhost_get_tag(struct se_portal_group *se_tpg) -{ - struct tcm_vhost_tpg *tpg = container_of(se_tpg, - struct tcm_vhost_tpg, se_tpg); - return tpg->tport_tpgt; -} - -static u32 tcm_vhost_get_default_depth(struct se_portal_group *se_tpg) -{ - return 1; -} - -static u32 tcm_vhost_get_pr_transport_id(struct se_portal_group *se_tpg, - struct se_node_acl *se_nacl, - struct t10_pr_registration *pr_reg, - int *format_code, - unsigned char *buf) -{ - struct tcm_vhost_tpg *tpg = container_of(se_tpg, - struct tcm_vhost_tpg, se_tpg); - struct tcm_vhost_tport *tport = tpg->tport; - - switch (tport->tport_proto_id) { - case SCSI_PROTOCOL_SAS: - return sas_get_pr_transport_id(se_tpg, se_nacl, pr_reg, - format_code, buf); - case SCSI_PROTOCOL_FCP: - return fc_get_pr_transport_id(se_tpg, se_nacl, pr_reg, - format_code, buf); - case SCSI_PROTOCOL_ISCSI: - return iscsi_get_pr_transport_id(se_tpg, se_nacl, pr_reg, - format_code, buf); - default: - pr_err("Unknown tport_proto_id: 0x%02x, using" - " SAS emulation\n", tport->tport_proto_id); - break; - } - - return sas_get_pr_transport_id(se_tpg, se_nacl, pr_reg, - format_code, buf); -} - -static u32 tcm_vhost_get_pr_transport_id_len(struct se_portal_group *se_tpg, - struct se_node_acl *se_nacl, - struct t10_pr_registration *pr_reg, - int *format_code) -{ - struct tcm_vhost_tpg *tpg = container_of(se_tpg, - struct tcm_vhost_tpg, se_tpg); - struct tcm_vhost_tport *tport = tpg->tport; - - switch (tport->tport_proto_id) { - case SCSI_PROTOCOL_SAS: - return sas_get_pr_transport_id_len(se_tpg, se_nacl, pr_reg, - format_code); - case SCSI_PROTOCOL_FCP: - return fc_get_pr_transport_id_len(se_tpg, se_nacl, pr_reg, - format_code); - case SCSI_PROTOCOL_ISCSI: - return iscsi_get_pr_transport_id_len(se_tpg, se_nacl, pr_reg, - format_code); - default: - pr_err("Unknown tport_proto_id: 0x%02x, using" - " SAS emulation\n", tport->tport_proto_id); - break; - } - - return sas_get_pr_transport_id_len(se_tpg, se_nacl, pr_reg, - format_code); -} - -static char *tcm_vhost_parse_pr_out_transport_id(struct se_portal_group *se_tpg, - const char *buf, - u32 *out_tid_len, - char **port_nexus_ptr) -{ - struct tcm_vhost_tpg *tpg = container_of(se_tpg, - struct tcm_vhost_tpg, se_tpg); - struct tcm_vhost_tport *tport = tpg->tport; - - switch (tport->tport_proto_id) { - case SCSI_PROTOCOL_SAS: - return sas_parse_pr_out_transport_id(se_tpg, buf, out_tid_len, - port_nexus_ptr); - case SCSI_PROTOCOL_FCP: - return fc_parse_pr_out_transport_id(se_tpg, buf, out_tid_len, - port_nexus_ptr); - case SCSI_PROTOCOL_ISCSI: - return iscsi_parse_pr_out_transport_id(se_tpg, buf, out_tid_len, - port_nexus_ptr); - default: - pr_err("Unknown tport_proto_id: 0x%02x, using" - " SAS emulation\n", tport->tport_proto_id); - break; - } - - return sas_parse_pr_out_transport_id(se_tpg, buf, out_tid_len, - port_nexus_ptr); -} - -static struct se_node_acl *tcm_vhost_alloc_fabric_acl( - struct se_portal_group *se_tpg) -{ - struct tcm_vhost_nacl *nacl; - - nacl = kzalloc(sizeof(struct tcm_vhost_nacl), GFP_KERNEL); - if (!nacl) { - pr_err("Unable to allocate struct tcm_vhost_nacl\n"); - return NULL; - } - - return &nacl->se_node_acl; -} - -static void tcm_vhost_release_fabric_acl(struct se_portal_group *se_tpg, - struct se_node_acl *se_nacl) -{ - struct tcm_vhost_nacl *nacl = container_of(se_nacl, - struct tcm_vhost_nacl, se_node_acl); - kfree(nacl); -} - -static u32 tcm_vhost_tpg_get_inst_index(struct se_portal_group *se_tpg) -{ - return 1; -} - -static void tcm_vhost_release_cmd(struct se_cmd *se_cmd) -{ - return; -} - -static int tcm_vhost_shutdown_session(struct se_session *se_sess) -{ - return 0; -} - -static void tcm_vhost_close_session(struct se_session *se_sess) -{ - return; -} - -static u32 tcm_vhost_sess_get_index(struct se_session *se_sess) -{ - return 0; -} - -static int tcm_vhost_write_pending(struct se_cmd *se_cmd) -{ - /* Go ahead and process the write immediately */ - target_execute_cmd(se_cmd); - return 0; -} - -static int tcm_vhost_write_pending_status(struct se_cmd *se_cmd) -{ - return 0; -} - -static void tcm_vhost_set_default_node_attrs(struct se_node_acl *nacl) -{ - return; -} - -static u32 tcm_vhost_get_task_tag(struct se_cmd *se_cmd) -{ - return 0; -} - -static int tcm_vhost_get_cmd_state(struct se_cmd *se_cmd) -{ - return 0; -} - -static void vhost_scsi_complete_cmd(struct tcm_vhost_cmd *tv_cmd) -{ - struct vhost_scsi *vs = tv_cmd->tvc_vhost; - - spin_lock_bh(&vs->vs_completion_lock); - list_add_tail(&tv_cmd->tvc_completion_list, &vs->vs_completion_list); - spin_unlock_bh(&vs->vs_completion_lock); - - vhost_work_queue(&vs->dev, &vs->vs_completion_work); -} - -static int tcm_vhost_queue_data_in(struct se_cmd *se_cmd) -{ - struct tcm_vhost_cmd *tv_cmd = container_of(se_cmd, - struct tcm_vhost_cmd, tvc_se_cmd); - vhost_scsi_complete_cmd(tv_cmd); - return 0; -} - -static int tcm_vhost_queue_status(struct se_cmd *se_cmd) -{ - struct tcm_vhost_cmd *tv_cmd = container_of(se_cmd, - struct tcm_vhost_cmd, tvc_se_cmd); - vhost_scsi_complete_cmd(tv_cmd); - return 0; -} - -static int tcm_vhost_queue_tm_rsp(struct se_cmd *se_cmd) -{ - return 0; -} - -static void vhost_scsi_free_cmd(struct tcm_vhost_cmd *tv_cmd) -{ - struct se_cmd *se_cmd = &tv_cmd->tvc_se_cmd; - - /* TODO locking against target/backend threads? */ - transport_generic_free_cmd(se_cmd, 1); - - if (tv_cmd->tvc_sgl_count) { - u32 i; - for (i = 0; i < tv_cmd->tvc_sgl_count; i++) - put_page(sg_page(&tv_cmd->tvc_sgl[i])); - - kfree(tv_cmd->tvc_sgl); - } - - kfree(tv_cmd); -} - -/* Dequeue a command from the completion list */ -static struct tcm_vhost_cmd *vhost_scsi_get_cmd_from_completion( - struct vhost_scsi *vs) -{ - struct tcm_vhost_cmd *tv_cmd = NULL; - - spin_lock_bh(&vs->vs_completion_lock); - if (list_empty(&vs->vs_completion_list)) { - spin_unlock_bh(&vs->vs_completion_lock); - return NULL; - } - - list_for_each_entry(tv_cmd, &vs->vs_completion_list, - tvc_completion_list) { - list_del(&tv_cmd->tvc_completion_list); - break; - } - spin_unlock_bh(&vs->vs_completion_lock); - return tv_cmd; -} - -/* Fill in status and signal that we are done processing this command - * - * This is scheduled in the vhost work queue so we are called with the owner - * process mm and can access the vring. - */ -static void vhost_scsi_complete_cmd_work(struct vhost_work *work) -{ - struct vhost_scsi *vs = container_of(work, struct vhost_scsi, - vs_completion_work); - struct tcm_vhost_cmd *tv_cmd; - - while ((tv_cmd = vhost_scsi_get_cmd_from_completion(vs))) { - struct virtio_scsi_cmd_resp v_rsp; - struct se_cmd *se_cmd = &tv_cmd->tvc_se_cmd; - int ret; - - pr_debug("%s tv_cmd %p resid %u status %#02x\n", __func__, - tv_cmd, se_cmd->residual_count, se_cmd->scsi_status); - - memset(&v_rsp, 0, sizeof(v_rsp)); - v_rsp.resid = se_cmd->residual_count; - /* TODO is status_qualifier field needed? */ - v_rsp.status = se_cmd->scsi_status; - v_rsp.sense_len = se_cmd->scsi_sense_length; - memcpy(v_rsp.sense, tv_cmd->tvc_sense_buf, - v_rsp.sense_len); - ret = copy_to_user(tv_cmd->tvc_resp, &v_rsp, sizeof(v_rsp)); - if (likely(ret == 0)) - vhost_add_used(&vs->vqs[2], tv_cmd->tvc_vq_desc, 0); - else - pr_err("Faulted on virtio_scsi_cmd_resp\n"); - - vhost_scsi_free_cmd(tv_cmd); - } - - vhost_signal(&vs->dev, &vs->vqs[2]); -} - -static struct tcm_vhost_cmd *vhost_scsi_allocate_cmd( - struct tcm_vhost_tpg *tv_tpg, - struct virtio_scsi_cmd_req *v_req, - u32 exp_data_len, - int data_direction) -{ - struct tcm_vhost_cmd *tv_cmd; - struct tcm_vhost_nexus *tv_nexus; - - tv_nexus = tv_tpg->tpg_nexus; - if (!tv_nexus) { - pr_err("Unable to locate active struct tcm_vhost_nexus\n"); - return ERR_PTR(-EIO); - } - - tv_cmd = kzalloc(sizeof(struct tcm_vhost_cmd), GFP_ATOMIC); - if (!tv_cmd) { - pr_err("Unable to allocate struct tcm_vhost_cmd\n"); - return ERR_PTR(-ENOMEM); - } - INIT_LIST_HEAD(&tv_cmd->tvc_completion_list); - tv_cmd->tvc_tag = v_req->tag; - tv_cmd->tvc_task_attr = v_req->task_attr; - tv_cmd->tvc_exp_data_len = exp_data_len; - tv_cmd->tvc_data_direction = data_direction; - tv_cmd->tvc_nexus = tv_nexus; - - return tv_cmd; -} - -/* - * Map a user memory range into a scatterlist - * - * Returns the number of scatterlist entries used or -errno on error. - */ -static int vhost_scsi_map_to_sgl(struct scatterlist *sgl, - unsigned int sgl_count, void __user *ptr, size_t len, int write) -{ - struct scatterlist *sg = sgl; - unsigned int npages = 0; - int ret; - - while (len > 0) { - struct page *page; - unsigned int offset = (uintptr_t)ptr & ~PAGE_MASK; - unsigned int nbytes = min_t(unsigned int, - PAGE_SIZE - offset, len); - - if (npages == sgl_count) { - ret = -ENOBUFS; - goto err; - } - - ret = get_user_pages_fast((unsigned long)ptr, 1, write, &page); - BUG_ON(ret == 0); /* we should either get our page or fail */ - if (ret < 0) - goto err; - - sg_set_page(sg, page, nbytes, offset); - ptr += nbytes; - len -= nbytes; - sg++; - npages++; - } - return npages; - -err: - /* Put pages that we hold */ - for (sg = sgl; sg != &sgl[npages]; sg++) - put_page(sg_page(sg)); - return ret; -} - -static int vhost_scsi_map_iov_to_sgl(struct tcm_vhost_cmd *tv_cmd, - struct iovec *iov, unsigned int niov, int write) -{ - int ret; - unsigned int i; - u32 sgl_count; - struct scatterlist *sg; - - /* - * Find out how long sglist needs to be - */ - sgl_count = 0; - for (i = 0; i < niov; i++) { - sgl_count += (((uintptr_t)iov[i].iov_base + iov[i].iov_len + - PAGE_SIZE - 1) >> PAGE_SHIFT) - - ((uintptr_t)iov[i].iov_base >> PAGE_SHIFT); - } - /* TODO overflow checking */ - - sg = kmalloc(sizeof(tv_cmd->tvc_sgl[0]) * sgl_count, GFP_ATOMIC); - if (!sg) - return -ENOMEM; - pr_debug("%s sg %p sgl_count %u is_err %d\n", __func__, - sg, sgl_count, !sg); - sg_init_table(sg, sgl_count); - - tv_cmd->tvc_sgl = sg; - tv_cmd->tvc_sgl_count = sgl_count; - - pr_debug("Mapping %u iovecs for %u pages\n", niov, sgl_count); - for (i = 0; i < niov; i++) { - ret = vhost_scsi_map_to_sgl(sg, sgl_count, iov[i].iov_base, - iov[i].iov_len, write); - if (ret < 0) { - for (i = 0; i < tv_cmd->tvc_sgl_count; i++) - put_page(sg_page(&tv_cmd->tvc_sgl[i])); - kfree(tv_cmd->tvc_sgl); - tv_cmd->tvc_sgl = NULL; - tv_cmd->tvc_sgl_count = 0; - return ret; - } - - sg += ret; - sgl_count -= ret; - } - return 0; -} - -static void tcm_vhost_submission_work(struct work_struct *work) -{ - struct tcm_vhost_cmd *tv_cmd = - container_of(work, struct tcm_vhost_cmd, work); - struct tcm_vhost_nexus *tv_nexus; - struct se_cmd *se_cmd = &tv_cmd->tvc_se_cmd; - struct scatterlist *sg_ptr, *sg_bidi_ptr = NULL; - int rc, sg_no_bidi = 0; - - if (tv_cmd->tvc_sgl_count) { - sg_ptr = tv_cmd->tvc_sgl; -/* FIXME: Fix BIDI operation in tcm_vhost_submission_work() */ -#if 0 - if (se_cmd->se_cmd_flags & SCF_BIDI) { - sg_bidi_ptr = NULL; - sg_no_bidi = 0; - } -#endif - } else { - sg_ptr = NULL; - } - tv_nexus = tv_cmd->tvc_nexus; - - rc = target_submit_cmd_map_sgls(se_cmd, tv_nexus->tvn_se_sess, - tv_cmd->tvc_cdb, &tv_cmd->tvc_sense_buf[0], - tv_cmd->tvc_lun, tv_cmd->tvc_exp_data_len, - tv_cmd->tvc_task_attr, tv_cmd->tvc_data_direction, - 0, sg_ptr, tv_cmd->tvc_sgl_count, - sg_bidi_ptr, sg_no_bidi); - if (rc < 0) { - transport_send_check_condition_and_sense(se_cmd, - TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE, 0); - transport_generic_free_cmd(se_cmd, 0); - } -} - -static void vhost_scsi_handle_vq(struct vhost_scsi *vs) -{ - struct vhost_virtqueue *vq = &vs->vqs[2]; - struct virtio_scsi_cmd_req v_req; - struct tcm_vhost_tpg *tv_tpg; - struct tcm_vhost_cmd *tv_cmd; - u32 exp_data_len, data_first, data_num, data_direction; - unsigned out, in, i; - int head, ret; - - /* Must use ioctl VHOST_SCSI_SET_ENDPOINT */ - tv_tpg = vs->vs_tpg; - if (unlikely(!tv_tpg)) { - pr_err("%s endpoint not set\n", __func__); - return; - } - - mutex_lock(&vq->mutex); - vhost_disable_notify(&vs->dev, vq); - - for (;;) { - head = vhost_get_vq_desc(&vs->dev, vq, vq->iov, - ARRAY_SIZE(vq->iov), &out, &in, - NULL, NULL); - pr_debug("vhost_get_vq_desc: head: %d, out: %u in: %u\n", - head, out, in); - /* On error, stop handling until the next kick. */ - if (unlikely(head < 0)) - break; - /* Nothing new? Wait for eventfd to tell us they refilled. */ - if (head == vq->num) { - if (unlikely(vhost_enable_notify(&vs->dev, vq))) { - vhost_disable_notify(&vs->dev, vq); - continue; - } - break; - } - -/* FIXME: BIDI operation */ - if (out == 1 && in == 1) { - data_direction = DMA_NONE; - data_first = 0; - data_num = 0; - } else if (out == 1 && in > 1) { - data_direction = DMA_FROM_DEVICE; - data_first = out + 1; - data_num = in - 1; - } else if (out > 1 && in == 1) { - data_direction = DMA_TO_DEVICE; - data_first = 1; - data_num = out - 1; - } else { - vq_err(vq, "Invalid buffer layout out: %u in: %u\n", - out, in); - break; - } - - /* - * Check for a sane resp buffer so we can report errors to - * the guest. - */ - if (unlikely(vq->iov[out].iov_len != - sizeof(struct virtio_scsi_cmd_resp))) { - vq_err(vq, "Expecting virtio_scsi_cmd_resp, got %zu" - " bytes\n", vq->iov[out].iov_len); - break; - } - - if (unlikely(vq->iov[0].iov_len != sizeof(v_req))) { - vq_err(vq, "Expecting virtio_scsi_cmd_req, got %zu" - " bytes\n", vq->iov[0].iov_len); - break; - } - pr_debug("Calling __copy_from_user: vq->iov[0].iov_base: %p," - " len: %zu\n", vq->iov[0].iov_base, sizeof(v_req)); - ret = __copy_from_user(&v_req, vq->iov[0].iov_base, - sizeof(v_req)); - if (unlikely(ret)) { - vq_err(vq, "Faulted on virtio_scsi_cmd_req\n"); - break; - } - - exp_data_len = 0; - for (i = 0; i < data_num; i++) - exp_data_len += vq->iov[data_first + i].iov_len; - - tv_cmd = vhost_scsi_allocate_cmd(tv_tpg, &v_req, - exp_data_len, data_direction); - if (IS_ERR(tv_cmd)) { - vq_err(vq, "vhost_scsi_allocate_cmd failed %ld\n", - PTR_ERR(tv_cmd)); - break; - } - pr_debug("Allocated tv_cmd: %p exp_data_len: %d, data_direction" - ": %d\n", tv_cmd, exp_data_len, data_direction); - - tv_cmd->tvc_vhost = vs; - - if (unlikely(vq->iov[out].iov_len != - sizeof(struct virtio_scsi_cmd_resp))) { - vq_err(vq, "Expecting virtio_scsi_cmd_resp, got %zu" - " bytes, out: %d, in: %d\n", - vq->iov[out].iov_len, out, in); - break; - } - - tv_cmd->tvc_resp = vq->iov[out].iov_base; - - /* - * Copy in the recieved CDB descriptor into tv_cmd->tvc_cdb - * that will be used by tcm_vhost_new_cmd_map() and down into - * target_setup_cmd_from_cdb() - */ - memcpy(tv_cmd->tvc_cdb, v_req.cdb, TCM_VHOST_MAX_CDB_SIZE); - /* - * Check that the recieved CDB size does not exceeded our - * hardcoded max for tcm_vhost - */ - /* TODO what if cdb was too small for varlen cdb header? */ - if (unlikely(scsi_command_size(tv_cmd->tvc_cdb) > - TCM_VHOST_MAX_CDB_SIZE)) { - vq_err(vq, "Received SCSI CDB with command_size: %d that" - " exceeds SCSI_MAX_VARLEN_CDB_SIZE: %d\n", - scsi_command_size(tv_cmd->tvc_cdb), - TCM_VHOST_MAX_CDB_SIZE); - break; /* TODO */ - } - tv_cmd->tvc_lun = ((v_req.lun[2] << 8) | v_req.lun[3]) & 0x3FFF; - - pr_debug("vhost_scsi got command opcode: %#02x, lun: %d\n", - tv_cmd->tvc_cdb[0], tv_cmd->tvc_lun); - - if (data_direction != DMA_NONE) { - ret = vhost_scsi_map_iov_to_sgl(tv_cmd, - &vq->iov[data_first], data_num, - data_direction == DMA_TO_DEVICE); - if (unlikely(ret)) { - vq_err(vq, "Failed to map iov to sgl\n"); - break; /* TODO */ - } - } - - /* - * Save the descriptor from vhost_get_vq_desc() to be used to - * complete the virtio-scsi request in TCM callback context via - * tcm_vhost_queue_data_in() and tcm_vhost_queue_status() - */ - tv_cmd->tvc_vq_desc = head; - /* - * Dispatch tv_cmd descriptor for cmwq execution in process - * context provided by tcm_vhost_workqueue. This also ensures - * tv_cmd is executed on the same kworker CPU as this vhost - * thread to gain positive L2 cache locality effects.. - */ - INIT_WORK(&tv_cmd->work, tcm_vhost_submission_work); - queue_work(tcm_vhost_workqueue, &tv_cmd->work); - } - - mutex_unlock(&vq->mutex); -} - -static void vhost_scsi_ctl_handle_kick(struct vhost_work *work) -{ - pr_debug("%s: The handling func for control queue.\n", __func__); -} - -static void vhost_scsi_evt_handle_kick(struct vhost_work *work) -{ - pr_debug("%s: The handling func for event queue.\n", __func__); -} - -static void vhost_scsi_handle_kick(struct vhost_work *work) -{ - struct vhost_virtqueue *vq = container_of(work, struct vhost_virtqueue, - poll.work); - struct vhost_scsi *vs = container_of(vq->dev, struct vhost_scsi, dev); - - vhost_scsi_handle_vq(vs); -} - -/* - * Called from vhost_scsi_ioctl() context to walk the list of available - * tcm_vhost_tpg with an active struct tcm_vhost_nexus - */ -static int vhost_scsi_set_endpoint( - struct vhost_scsi *vs, - struct vhost_scsi_target *t) -{ - struct tcm_vhost_tport *tv_tport; - struct tcm_vhost_tpg *tv_tpg; - int index; - - mutex_lock(&vs->dev.mutex); - /* Verify that ring has been setup correctly. */ - for (index = 0; index < vs->dev.nvqs; ++index) { - /* Verify that ring has been setup correctly. */ - if (!vhost_vq_access_ok(&vs->vqs[index])) { - mutex_unlock(&vs->dev.mutex); - return -EFAULT; - } - } - mutex_unlock(&vs->dev.mutex); - - mutex_lock(&tcm_vhost_mutex); - list_for_each_entry(tv_tpg, &tcm_vhost_list, tv_tpg_list) { - mutex_lock(&tv_tpg->tv_tpg_mutex); - if (!tv_tpg->tpg_nexus) { - mutex_unlock(&tv_tpg->tv_tpg_mutex); - continue; - } - if (tv_tpg->tv_tpg_vhost_count != 0) { - mutex_unlock(&tv_tpg->tv_tpg_mutex); - continue; - } - tv_tport = tv_tpg->tport; - - if (!strcmp(tv_tport->tport_name, t->vhost_wwpn) && - (tv_tpg->tport_tpgt == t->vhost_tpgt)) { - tv_tpg->tv_tpg_vhost_count++; - mutex_unlock(&tv_tpg->tv_tpg_mutex); - mutex_unlock(&tcm_vhost_mutex); - - mutex_lock(&vs->dev.mutex); - if (vs->vs_tpg) { - mutex_unlock(&vs->dev.mutex); - mutex_lock(&tv_tpg->tv_tpg_mutex); - tv_tpg->tv_tpg_vhost_count--; - mutex_unlock(&tv_tpg->tv_tpg_mutex); - return -EEXIST; - } - - vs->vs_tpg = tv_tpg; - smp_mb__after_atomic_inc(); - mutex_unlock(&vs->dev.mutex); - return 0; - } - mutex_unlock(&tv_tpg->tv_tpg_mutex); - } - mutex_unlock(&tcm_vhost_mutex); - return -EINVAL; -} - -static int vhost_scsi_clear_endpoint( - struct vhost_scsi *vs, - struct vhost_scsi_target *t) -{ - struct tcm_vhost_tport *tv_tport; - struct tcm_vhost_tpg *tv_tpg; - int index, ret; - - mutex_lock(&vs->dev.mutex); - /* Verify that ring has been setup correctly. */ - for (index = 0; index < vs->dev.nvqs; ++index) { - if (!vhost_vq_access_ok(&vs->vqs[index])) { - ret = -EFAULT; - goto err; - } - } - - if (!vs->vs_tpg) { - ret = -ENODEV; - goto err; - } - tv_tpg = vs->vs_tpg; - tv_tport = tv_tpg->tport; - - if (strcmp(tv_tport->tport_name, t->vhost_wwpn) || - (tv_tpg->tport_tpgt != t->vhost_tpgt)) { - pr_warn("tv_tport->tport_name: %s, tv_tpg->tport_tpgt: %hu" - " does not match t->vhost_wwpn: %s, t->vhost_tpgt: %hu\n", - tv_tport->tport_name, tv_tpg->tport_tpgt, - t->vhost_wwpn, t->vhost_tpgt); - ret = -EINVAL; - goto err; - } - tv_tpg->tv_tpg_vhost_count--; - vs->vs_tpg = NULL; - mutex_unlock(&vs->dev.mutex); - - return 0; - -err: - mutex_unlock(&vs->dev.mutex); - return ret; -} - -static int vhost_scsi_open(struct inode *inode, struct file *f) -{ - struct vhost_scsi *s; - int r; - - s = kzalloc(sizeof(*s), GFP_KERNEL); - if (!s) - return -ENOMEM; - - vhost_work_init(&s->vs_completion_work, vhost_scsi_complete_cmd_work); - INIT_LIST_HEAD(&s->vs_completion_list); - spin_lock_init(&s->vs_completion_lock); - - s->vqs[VHOST_SCSI_VQ_CTL].handle_kick = vhost_scsi_ctl_handle_kick; - s->vqs[VHOST_SCSI_VQ_EVT].handle_kick = vhost_scsi_evt_handle_kick; - s->vqs[VHOST_SCSI_VQ_IO].handle_kick = vhost_scsi_handle_kick; - r = vhost_dev_init(&s->dev, s->vqs, 3); - if (r < 0) { - kfree(s); - return r; - } - - f->private_data = s; - return 0; -} - -static int vhost_scsi_release(struct inode *inode, struct file *f) -{ - struct vhost_scsi *s = f->private_data; - - if (s->vs_tpg && s->vs_tpg->tport) { - struct vhost_scsi_target backend; - - memcpy(backend.vhost_wwpn, s->vs_tpg->tport->tport_name, - sizeof(backend.vhost_wwpn)); - backend.vhost_tpgt = s->vs_tpg->tport_tpgt; - vhost_scsi_clear_endpoint(s, &backend); - } - - vhost_dev_stop(&s->dev); - vhost_dev_cleanup(&s->dev, false); - kfree(s); - return 0; -} - -static void vhost_scsi_flush_vq(struct vhost_scsi *vs, int index) -{ - vhost_poll_flush(&vs->dev.vqs[index].poll); -} - -static void vhost_scsi_flush(struct vhost_scsi *vs) -{ - vhost_scsi_flush_vq(vs, VHOST_SCSI_VQ_CTL); - vhost_scsi_flush_vq(vs, VHOST_SCSI_VQ_EVT); - vhost_scsi_flush_vq(vs, VHOST_SCSI_VQ_IO); -} - -static int vhost_scsi_set_features(struct vhost_scsi *vs, u64 features) -{ - if (features & ~VHOST_FEATURES) - return -EOPNOTSUPP; - - mutex_lock(&vs->dev.mutex); - if ((features & (1 << VHOST_F_LOG_ALL)) && - !vhost_log_access_ok(&vs->dev)) { - mutex_unlock(&vs->dev.mutex); - return -EFAULT; - } - vs->dev.acked_features = features; - smp_wmb(); - vhost_scsi_flush(vs); - mutex_unlock(&vs->dev.mutex); - return 0; -} - -static long vhost_scsi_ioctl(struct file *f, unsigned int ioctl, - unsigned long arg) -{ - struct vhost_scsi *vs = f->private_data; - struct vhost_scsi_target backend; - void __user *argp = (void __user *)arg; - u64 __user *featurep = argp; - u64 features; - int r, abi_version = VHOST_SCSI_ABI_VERSION; - - switch (ioctl) { - case VHOST_SCSI_SET_ENDPOINT: - if (copy_from_user(&backend, argp, sizeof backend)) - return -EFAULT; - if (backend.reserved != 0) - return -EOPNOTSUPP; - - return vhost_scsi_set_endpoint(vs, &backend); - case VHOST_SCSI_CLEAR_ENDPOINT: - if (copy_from_user(&backend, argp, sizeof backend)) - return -EFAULT; - if (backend.reserved != 0) - return -EOPNOTSUPP; - - return vhost_scsi_clear_endpoint(vs, &backend); - case VHOST_SCSI_GET_ABI_VERSION: - if (copy_to_user(argp, &abi_version, sizeof abi_version)) - return -EFAULT; - return 0; - case VHOST_GET_FEATURES: - features = VHOST_FEATURES; - if (copy_to_user(featurep, &features, sizeof features)) - return -EFAULT; - return 0; - case VHOST_SET_FEATURES: - if (copy_from_user(&features, featurep, sizeof features)) - return -EFAULT; - return vhost_scsi_set_features(vs, features); - default: - mutex_lock(&vs->dev.mutex); - r = vhost_dev_ioctl(&vs->dev, ioctl, argp); - /* TODO: flush backend after dev ioctl. */ - if (r == -ENOIOCTLCMD) - r = vhost_vring_ioctl(&vs->dev, ioctl, argp); - mutex_unlock(&vs->dev.mutex); - return r; - } -} - -#ifdef CONFIG_COMPAT -static long vhost_scsi_compat_ioctl(struct file *f, unsigned int ioctl, - unsigned long arg) -{ - return vhost_scsi_ioctl(f, ioctl, (unsigned long)compat_ptr(arg)); -} -#endif - -static const struct file_operations vhost_scsi_fops = { - .owner = THIS_MODULE, - .release = vhost_scsi_release, - .unlocked_ioctl = vhost_scsi_ioctl, -#ifdef CONFIG_COMPAT - .compat_ioctl = vhost_scsi_compat_ioctl, -#endif - .open = vhost_scsi_open, - .llseek = noop_llseek, -}; - -static struct miscdevice vhost_scsi_misc = { - MISC_DYNAMIC_MINOR, - "vhost-scsi", - &vhost_scsi_fops, -}; - -static int __init vhost_scsi_register(void) -{ - return misc_register(&vhost_scsi_misc); -} - -static int vhost_scsi_deregister(void) -{ - return misc_deregister(&vhost_scsi_misc); -} - -static char *tcm_vhost_dump_proto_id(struct tcm_vhost_tport *tport) -{ - switch (tport->tport_proto_id) { - case SCSI_PROTOCOL_SAS: - return "SAS"; - case SCSI_PROTOCOL_FCP: - return "FCP"; - case SCSI_PROTOCOL_ISCSI: - return "iSCSI"; - default: - break; - } - - return "Unknown"; -} - -static int tcm_vhost_port_link(struct se_portal_group *se_tpg, - struct se_lun *lun) -{ - struct tcm_vhost_tpg *tv_tpg = container_of(se_tpg, - struct tcm_vhost_tpg, se_tpg); - - mutex_lock(&tv_tpg->tv_tpg_mutex); - tv_tpg->tv_tpg_port_count++; - mutex_unlock(&tv_tpg->tv_tpg_mutex); - - return 0; -} - -static void tcm_vhost_port_unlink(struct se_portal_group *se_tpg, - struct se_lun *se_lun) -{ - struct tcm_vhost_tpg *tv_tpg = container_of(se_tpg, - struct tcm_vhost_tpg, se_tpg); - - mutex_lock(&tv_tpg->tv_tpg_mutex); - tv_tpg->tv_tpg_port_count--; - mutex_unlock(&tv_tpg->tv_tpg_mutex); -} - -static struct se_node_acl *tcm_vhost_make_nodeacl( - struct se_portal_group *se_tpg, - struct config_group *group, - const char *name) -{ - struct se_node_acl *se_nacl, *se_nacl_new; - struct tcm_vhost_nacl *nacl; - u64 wwpn = 0; - u32 nexus_depth; - - /* tcm_vhost_parse_wwn(name, &wwpn, 1) < 0) - return ERR_PTR(-EINVAL); */ - se_nacl_new = tcm_vhost_alloc_fabric_acl(se_tpg); - if (!se_nacl_new) - return ERR_PTR(-ENOMEM); - - nexus_depth = 1; - /* - * se_nacl_new may be released by core_tpg_add_initiator_node_acl() - * when converting a NodeACL from demo mode -> explict - */ - se_nacl = core_tpg_add_initiator_node_acl(se_tpg, se_nacl_new, - name, nexus_depth); - if (IS_ERR(se_nacl)) { - tcm_vhost_release_fabric_acl(se_tpg, se_nacl_new); - return se_nacl; - } - /* - * Locate our struct tcm_vhost_nacl and set the FC Nport WWPN - */ - nacl = container_of(se_nacl, struct tcm_vhost_nacl, se_node_acl); - nacl->iport_wwpn = wwpn; - - return se_nacl; -} - -static void tcm_vhost_drop_nodeacl(struct se_node_acl *se_acl) -{ - struct tcm_vhost_nacl *nacl = container_of(se_acl, - struct tcm_vhost_nacl, se_node_acl); - core_tpg_del_initiator_node_acl(se_acl->se_tpg, se_acl, 1); - kfree(nacl); -} - -static int tcm_vhost_make_nexus(struct tcm_vhost_tpg *tv_tpg, - const char *name) -{ - struct se_portal_group *se_tpg; - struct tcm_vhost_nexus *tv_nexus; - - mutex_lock(&tv_tpg->tv_tpg_mutex); - if (tv_tpg->tpg_nexus) { - mutex_unlock(&tv_tpg->tv_tpg_mutex); - pr_debug("tv_tpg->tpg_nexus already exists\n"); - return -EEXIST; - } - se_tpg = &tv_tpg->se_tpg; - - tv_nexus = kzalloc(sizeof(struct tcm_vhost_nexus), GFP_KERNEL); - if (!tv_nexus) { - mutex_unlock(&tv_tpg->tv_tpg_mutex); - pr_err("Unable to allocate struct tcm_vhost_nexus\n"); - return -ENOMEM; - } - /* - * Initialize the struct se_session pointer - */ - tv_nexus->tvn_se_sess = transport_init_session(); - if (IS_ERR(tv_nexus->tvn_se_sess)) { - mutex_unlock(&tv_tpg->tv_tpg_mutex); - kfree(tv_nexus); - return -ENOMEM; - } - /* - * Since we are running in 'demo mode' this call with generate a - * struct se_node_acl for the tcm_vhost 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) { - mutex_unlock(&tv_tpg->tv_tpg_mutex); - pr_debug("core_tpg_check_initiator_node_acl() failed" - " for %s\n", name); - transport_free_session(tv_nexus->tvn_se_sess); - kfree(tv_nexus); - return -ENOMEM; - } - /* - * Now register the TCM vhost virtual I_T Nexus as active with the - * call to __transport_register_session() - */ - __transport_register_session(se_tpg, tv_nexus->tvn_se_sess->se_node_acl, - tv_nexus->tvn_se_sess, tv_nexus); - tv_tpg->tpg_nexus = tv_nexus; - - mutex_unlock(&tv_tpg->tv_tpg_mutex); - return 0; -} - -static int tcm_vhost_drop_nexus(struct tcm_vhost_tpg *tpg) -{ - struct se_session *se_sess; - struct tcm_vhost_nexus *tv_nexus; - - mutex_lock(&tpg->tv_tpg_mutex); - tv_nexus = tpg->tpg_nexus; - if (!tv_nexus) { - mutex_unlock(&tpg->tv_tpg_mutex); - return -ENODEV; - } - - se_sess = tv_nexus->tvn_se_sess; - if (!se_sess) { - mutex_unlock(&tpg->tv_tpg_mutex); - return -ENODEV; - } - - if (tpg->tv_tpg_port_count != 0) { - mutex_unlock(&tpg->tv_tpg_mutex); - pr_err("Unable to remove TCM_vhost I_T Nexus with" - " active TPG port count: %d\n", - tpg->tv_tpg_port_count); - return -EBUSY; - } - - if (tpg->tv_tpg_vhost_count != 0) { - mutex_unlock(&tpg->tv_tpg_mutex); - pr_err("Unable to remove TCM_vhost I_T Nexus with" - " active TPG vhost count: %d\n", - tpg->tv_tpg_vhost_count); - return -EBUSY; - } - - pr_debug("TCM_vhost_ConfigFS: Removing I_T Nexus to emulated" - " %s Initiator Port: %s\n", tcm_vhost_dump_proto_id(tpg->tport), - tv_nexus->tvn_se_sess->se_node_acl->initiatorname); - /* - * Release the SCSI I_T Nexus to the emulated vhost Target Port - */ - transport_deregister_session(tv_nexus->tvn_se_sess); - tpg->tpg_nexus = NULL; - mutex_unlock(&tpg->tv_tpg_mutex); - - kfree(tv_nexus); - return 0; -} - -static ssize_t tcm_vhost_tpg_show_nexus(struct se_portal_group *se_tpg, - char *page) -{ - struct tcm_vhost_tpg *tv_tpg = container_of(se_tpg, - struct tcm_vhost_tpg, se_tpg); - struct tcm_vhost_nexus *tv_nexus; - ssize_t ret; - - mutex_lock(&tv_tpg->tv_tpg_mutex); - tv_nexus = tv_tpg->tpg_nexus; - if (!tv_nexus) { - mutex_unlock(&tv_tpg->tv_tpg_mutex); - return -ENODEV; - } - ret = snprintf(page, PAGE_SIZE, "%s\n", - tv_nexus->tvn_se_sess->se_node_acl->initiatorname); - mutex_unlock(&tv_tpg->tv_tpg_mutex); - - return ret; -} - -static ssize_t tcm_vhost_tpg_store_nexus(struct se_portal_group *se_tpg, - const char *page, - size_t count) -{ - struct tcm_vhost_tpg *tv_tpg = container_of(se_tpg, - struct tcm_vhost_tpg, se_tpg); - struct tcm_vhost_tport *tport_wwn = tv_tpg->tport; - unsigned char i_port[TCM_VHOST_NAMELEN], *ptr, *port_ptr; - int ret; - /* - * Shutdown the active I_T nexus if 'NULL' is passed.. - */ - if (!strncmp(page, "NULL", 4)) { - ret = tcm_vhost_drop_nexus(tv_tpg); - return (!ret) ? count : ret; - } - /* - * Otherwise make sure the passed virtual Initiator port WWN matches - * the fabric protocol_id set in tcm_vhost_make_tport(), and call - * tcm_vhost_make_nexus(). - */ - if (strlen(page) >= TCM_VHOST_NAMELEN) { - pr_err("Emulated NAA Sas Address: %s, exceeds" - " max: %d\n", page, TCM_VHOST_NAMELEN); - return -EINVAL; - } - snprintf(&i_port[0], TCM_VHOST_NAMELEN, "%s", page); - - ptr = strstr(i_port, "naa."); - if (ptr) { - if (tport_wwn->tport_proto_id != SCSI_PROTOCOL_SAS) { - pr_err("Passed SAS Initiator Port %s does not" - " match target port protoid: %s\n", i_port, - tcm_vhost_dump_proto_id(tport_wwn)); - return -EINVAL; - } - port_ptr = &i_port[0]; - goto check_newline; - } - ptr = strstr(i_port, "fc."); - if (ptr) { - if (tport_wwn->tport_proto_id != SCSI_PROTOCOL_FCP) { - pr_err("Passed FCP Initiator Port %s does not" - " match target port protoid: %s\n", i_port, - tcm_vhost_dump_proto_id(tport_wwn)); - return -EINVAL; - } - port_ptr = &i_port[3]; /* Skip over "fc." */ - goto check_newline; - } - ptr = strstr(i_port, "iqn."); - if (ptr) { - if (tport_wwn->tport_proto_id != SCSI_PROTOCOL_ISCSI) { - pr_err("Passed iSCSI Initiator Port %s does not" - " match target port protoid: %s\n", i_port, - tcm_vhost_dump_proto_id(tport_wwn)); - return -EINVAL; - } - port_ptr = &i_port[0]; - goto check_newline; - } - pr_err("Unable to locate prefix for emulated Initiator Port:" - " %s\n", i_port); - return -EINVAL; - /* - * Clear any trailing newline for the NAA WWN - */ -check_newline: - if (i_port[strlen(i_port)-1] == '\n') - i_port[strlen(i_port)-1] = '\0'; - - ret = tcm_vhost_make_nexus(tv_tpg, port_ptr); - if (ret < 0) - return ret; - - return count; -} - -TF_TPG_BASE_ATTR(tcm_vhost, nexus, S_IRUGO | S_IWUSR); - -static struct configfs_attribute *tcm_vhost_tpg_attrs[] = { - &tcm_vhost_tpg_nexus.attr, - NULL, -}; - -static struct se_portal_group *tcm_vhost_make_tpg(struct se_wwn *wwn, - struct config_group *group, - const char *name) -{ - struct tcm_vhost_tport *tport = container_of(wwn, - struct tcm_vhost_tport, tport_wwn); - - struct tcm_vhost_tpg *tpg; - unsigned long tpgt; - int ret; - - if (strstr(name, "tpgt_") != name) - return ERR_PTR(-EINVAL); - if (kstrtoul(name + 5, 10, &tpgt) || tpgt > UINT_MAX) - return ERR_PTR(-EINVAL); - - tpg = kzalloc(sizeof(struct tcm_vhost_tpg), GFP_KERNEL); - if (!tpg) { - pr_err("Unable to allocate struct tcm_vhost_tpg"); - return ERR_PTR(-ENOMEM); - } - mutex_init(&tpg->tv_tpg_mutex); - INIT_LIST_HEAD(&tpg->tv_tpg_list); - tpg->tport = tport; - tpg->tport_tpgt = tpgt; - - ret = core_tpg_register(&tcm_vhost_fabric_configfs->tf_ops, wwn, - &tpg->se_tpg, tpg, TRANSPORT_TPG_TYPE_NORMAL); - if (ret < 0) { - kfree(tpg); - return NULL; - } - mutex_lock(&tcm_vhost_mutex); - list_add_tail(&tpg->tv_tpg_list, &tcm_vhost_list); - mutex_unlock(&tcm_vhost_mutex); - - return &tpg->se_tpg; -} - -static void tcm_vhost_drop_tpg(struct se_portal_group *se_tpg) -{ - struct tcm_vhost_tpg *tpg = container_of(se_tpg, - struct tcm_vhost_tpg, se_tpg); - - mutex_lock(&tcm_vhost_mutex); - list_del(&tpg->tv_tpg_list); - mutex_unlock(&tcm_vhost_mutex); - /* - * Release the virtual I_T Nexus for this vhost TPG - */ - tcm_vhost_drop_nexus(tpg); - /* - * Deregister the se_tpg from TCM.. - */ - core_tpg_deregister(se_tpg); - kfree(tpg); -} - -static struct se_wwn *tcm_vhost_make_tport(struct target_fabric_configfs *tf, - struct config_group *group, - const char *name) -{ - struct tcm_vhost_tport *tport; - char *ptr; - u64 wwpn = 0; - int off = 0; - - /* if (tcm_vhost_parse_wwn(name, &wwpn, 1) < 0) - return ERR_PTR(-EINVAL); */ - - tport = kzalloc(sizeof(struct tcm_vhost_tport), GFP_KERNEL); - if (!tport) { - pr_err("Unable to allocate struct tcm_vhost_tport"); - return ERR_PTR(-ENOMEM); - } - tport->tport_wwpn = wwpn; - /* - * Determine the emulated Protocol Identifier and Target Port Name - * based on the incoming configfs directory name. - */ - ptr = strstr(name, "naa."); - if (ptr) { - tport->tport_proto_id = SCSI_PROTOCOL_SAS; - goto check_len; - } - ptr = strstr(name, "fc."); - if (ptr) { - tport->tport_proto_id = SCSI_PROTOCOL_FCP; - off = 3; /* Skip over "fc." */ - goto check_len; - } - ptr = strstr(name, "iqn."); - if (ptr) { - tport->tport_proto_id = SCSI_PROTOCOL_ISCSI; - goto check_len; - } - - pr_err("Unable to locate prefix for emulated Target Port:" - " %s\n", name); - kfree(tport); - return ERR_PTR(-EINVAL); - -check_len: - if (strlen(name) >= TCM_VHOST_NAMELEN) { - pr_err("Emulated %s Address: %s, exceeds" - " max: %d\n", name, tcm_vhost_dump_proto_id(tport), - TCM_VHOST_NAMELEN); - kfree(tport); - return ERR_PTR(-EINVAL); - } - snprintf(&tport->tport_name[0], TCM_VHOST_NAMELEN, "%s", &name[off]); - - pr_debug("TCM_VHost_ConfigFS: Allocated emulated Target" - " %s Address: %s\n", tcm_vhost_dump_proto_id(tport), name); - - return &tport->tport_wwn; -} - -static void tcm_vhost_drop_tport(struct se_wwn *wwn) -{ - struct tcm_vhost_tport *tport = container_of(wwn, - struct tcm_vhost_tport, tport_wwn); - - pr_debug("TCM_VHost_ConfigFS: Deallocating emulated Target" - " %s Address: %s\n", tcm_vhost_dump_proto_id(tport), - tport->tport_name); - - kfree(tport); -} - -static ssize_t tcm_vhost_wwn_show_attr_version( - struct target_fabric_configfs *tf, - char *page) -{ - return sprintf(page, "TCM_VHOST fabric module %s on %s/%s" - "on "UTS_RELEASE"\n", TCM_VHOST_VERSION, utsname()->sysname, - utsname()->machine); -} - -TF_WWN_ATTR_RO(tcm_vhost, version); - -static struct configfs_attribute *tcm_vhost_wwn_attrs[] = { - &tcm_vhost_wwn_version.attr, - NULL, -}; - -static struct target_core_fabric_ops tcm_vhost_ops = { - .get_fabric_name = tcm_vhost_get_fabric_name, - .get_fabric_proto_ident = tcm_vhost_get_fabric_proto_ident, - .tpg_get_wwn = tcm_vhost_get_fabric_wwn, - .tpg_get_tag = tcm_vhost_get_tag, - .tpg_get_default_depth = tcm_vhost_get_default_depth, - .tpg_get_pr_transport_id = tcm_vhost_get_pr_transport_id, - .tpg_get_pr_transport_id_len = tcm_vhost_get_pr_transport_id_len, - .tpg_parse_pr_out_transport_id = tcm_vhost_parse_pr_out_transport_id, - .tpg_check_demo_mode = tcm_vhost_check_true, - .tpg_check_demo_mode_cache = tcm_vhost_check_true, - .tpg_check_demo_mode_write_protect = tcm_vhost_check_false, - .tpg_check_prod_mode_write_protect = tcm_vhost_check_false, - .tpg_alloc_fabric_acl = tcm_vhost_alloc_fabric_acl, - .tpg_release_fabric_acl = tcm_vhost_release_fabric_acl, - .tpg_get_inst_index = tcm_vhost_tpg_get_inst_index, - .release_cmd = tcm_vhost_release_cmd, - .shutdown_session = tcm_vhost_shutdown_session, - .close_session = tcm_vhost_close_session, - .sess_get_index = tcm_vhost_sess_get_index, - .sess_get_initiator_sid = NULL, - .write_pending = tcm_vhost_write_pending, - .write_pending_status = tcm_vhost_write_pending_status, - .set_default_node_attributes = tcm_vhost_set_default_node_attrs, - .get_task_tag = tcm_vhost_get_task_tag, - .get_cmd_state = tcm_vhost_get_cmd_state, - .queue_data_in = tcm_vhost_queue_data_in, - .queue_status = tcm_vhost_queue_status, - .queue_tm_rsp = tcm_vhost_queue_tm_rsp, - /* - * Setup callers for generic logic in target_core_fabric_configfs.c - */ - .fabric_make_wwn = tcm_vhost_make_tport, - .fabric_drop_wwn = tcm_vhost_drop_tport, - .fabric_make_tpg = tcm_vhost_make_tpg, - .fabric_drop_tpg = tcm_vhost_drop_tpg, - .fabric_post_link = tcm_vhost_port_link, - .fabric_pre_unlink = tcm_vhost_port_unlink, - .fabric_make_np = NULL, - .fabric_drop_np = NULL, - .fabric_make_nodeacl = tcm_vhost_make_nodeacl, - .fabric_drop_nodeacl = tcm_vhost_drop_nodeacl, -}; - -static int tcm_vhost_register_configfs(void) -{ - struct target_fabric_configfs *fabric; - int ret; - - pr_debug("TCM_VHOST fabric module %s on %s/%s" - " on "UTS_RELEASE"\n", TCM_VHOST_VERSION, utsname()->sysname, - utsname()->machine); - /* - * Register the top level struct config_item_type with TCM core - */ - fabric = target_fabric_configfs_init(THIS_MODULE, "vhost"); - if (IS_ERR(fabric)) { - pr_err("target_fabric_configfs_init() failed\n"); - return PTR_ERR(fabric); - } - /* - * Setup fabric->tf_ops from our local tcm_vhost_ops - */ - fabric->tf_ops = tcm_vhost_ops; - /* - * Setup default attribute lists for various fabric->tf_cit_tmpl - */ - TF_CIT_TMPL(fabric)->tfc_wwn_cit.ct_attrs = tcm_vhost_wwn_attrs; - TF_CIT_TMPL(fabric)->tfc_tpg_base_cit.ct_attrs = tcm_vhost_tpg_attrs; - TF_CIT_TMPL(fabric)->tfc_tpg_attrib_cit.ct_attrs = NULL; - TF_CIT_TMPL(fabric)->tfc_tpg_param_cit.ct_attrs = NULL; - TF_CIT_TMPL(fabric)->tfc_tpg_np_base_cit.ct_attrs = NULL; - TF_CIT_TMPL(fabric)->tfc_tpg_nacl_base_cit.ct_attrs = NULL; - TF_CIT_TMPL(fabric)->tfc_tpg_nacl_attrib_cit.ct_attrs = NULL; - TF_CIT_TMPL(fabric)->tfc_tpg_nacl_auth_cit.ct_attrs = NULL; - TF_CIT_TMPL(fabric)->tfc_tpg_nacl_param_cit.ct_attrs = NULL; - /* - * Register the fabric for use within TCM - */ - ret = target_fabric_configfs_register(fabric); - if (ret < 0) { - pr_err("target_fabric_configfs_register() failed" - " for TCM_VHOST\n"); - return ret; - } - /* - * Setup our local pointer to *fabric - */ - tcm_vhost_fabric_configfs = fabric; - pr_debug("TCM_VHOST[0] - Set fabric -> tcm_vhost_fabric_configfs\n"); - return 0; -}; - -static void tcm_vhost_deregister_configfs(void) -{ - if (!tcm_vhost_fabric_configfs) - return; - - target_fabric_configfs_deregister(tcm_vhost_fabric_configfs); - tcm_vhost_fabric_configfs = NULL; - pr_debug("TCM_VHOST[0] - Cleared tcm_vhost_fabric_configfs\n"); -}; - -static int __init tcm_vhost_init(void) -{ - int ret = -ENOMEM; - /* - * Use our own dedicated workqueue for submitting I/O into - * target core to avoid contention within system_wq. - */ - tcm_vhost_workqueue = alloc_workqueue("tcm_vhost", 0, 0); - if (!tcm_vhost_workqueue) - goto out; - - ret = vhost_scsi_register(); - if (ret < 0) - goto out_destroy_workqueue; - - ret = tcm_vhost_register_configfs(); - if (ret < 0) - goto out_vhost_scsi_deregister; - - return 0; - -out_vhost_scsi_deregister: - vhost_scsi_deregister(); -out_destroy_workqueue: - destroy_workqueue(tcm_vhost_workqueue); -out: - return ret; -}; - -static void tcm_vhost_exit(void) -{ - tcm_vhost_deregister_configfs(); - vhost_scsi_deregister(); - destroy_workqueue(tcm_vhost_workqueue); -}; - -MODULE_DESCRIPTION("TCM_VHOST series fabric driver"); -MODULE_LICENSE("GPL"); -module_init(tcm_vhost_init); -module_exit(tcm_vhost_exit); diff --git a/drivers/vhost/tcm_vhost.h b/drivers/vhost/tcm_vhost.h deleted file mode 100644 index 7e87c63ecbc..00000000000 --- a/drivers/vhost/tcm_vhost.h +++ /dev/null @@ -1,111 +0,0 @@ -#define TCM_VHOST_VERSION "v0.1" -#define TCM_VHOST_NAMELEN 256 -#define TCM_VHOST_MAX_CDB_SIZE 32 - -struct tcm_vhost_cmd { - /* Descriptor from vhost_get_vq_desc() for virt_queue segment */ - int tvc_vq_desc; - /* virtio-scsi initiator task attribute */ - int tvc_task_attr; - /* virtio-scsi initiator data direction */ - enum dma_data_direction tvc_data_direction; - /* Expected data transfer length from virtio-scsi header */ - u32 tvc_exp_data_len; - /* The Tag from include/linux/virtio_scsi.h:struct virtio_scsi_cmd_req */ - u64 tvc_tag; - /* The number of scatterlists associated with this cmd */ - u32 tvc_sgl_count; - /* Saved unpacked SCSI LUN for tcm_vhost_submission_work() */ - u32 tvc_lun; - /* Pointer to the SGL formatted memory from virtio-scsi */ - struct scatterlist *tvc_sgl; - /* Pointer to response */ - struct virtio_scsi_cmd_resp __user *tvc_resp; - /* Pointer to vhost_scsi for our device */ - struct vhost_scsi *tvc_vhost; - /* Pointer to vhost nexus memory */ - struct tcm_vhost_nexus *tvc_nexus; - /* The TCM I/O descriptor that is accessed via container_of() */ - struct se_cmd tvc_se_cmd; - /* work item used for cmwq dispatch to tcm_vhost_submission_work() */ - struct work_struct work; - /* Copy of the incoming SCSI command descriptor block (CDB) */ - unsigned char tvc_cdb[TCM_VHOST_MAX_CDB_SIZE]; - /* Sense buffer that will be mapped into outgoing status */ - unsigned char tvc_sense_buf[TRANSPORT_SENSE_BUFFER]; - /* Completed commands list, serviced from vhost worker thread */ - struct list_head tvc_completion_list; -}; - -struct tcm_vhost_nexus { - /* Pointer to TCM session for I_T Nexus */ - struct se_session *tvn_se_sess; -}; - -struct tcm_vhost_nacl { - /* Binary World Wide unique Port Name for Vhost Initiator port */ - u64 iport_wwpn; - /* ASCII formatted WWPN for Sas Initiator port */ - char iport_name[TCM_VHOST_NAMELEN]; - /* Returned by tcm_vhost_make_nodeacl() */ - struct se_node_acl se_node_acl; -}; - -struct tcm_vhost_tpg { - /* Vhost port target portal group tag for TCM */ - u16 tport_tpgt; - /* Used to track number of TPG Port/Lun Links wrt to explict I_T Nexus shutdown */ - int tv_tpg_port_count; - /* Used for vhost_scsi device reference to tpg_nexus, protected by tv_tpg_mutex */ - int tv_tpg_vhost_count; - /* list for tcm_vhost_list */ - struct list_head tv_tpg_list; - /* Used to protect access for tpg_nexus */ - struct mutex tv_tpg_mutex; - /* Pointer to the TCM VHost I_T Nexus for this TPG endpoint */ - struct tcm_vhost_nexus *tpg_nexus; - /* Pointer back to tcm_vhost_tport */ - struct tcm_vhost_tport *tport; - /* Returned by tcm_vhost_make_tpg() */ - struct se_portal_group se_tpg; -}; - -struct tcm_vhost_tport { - /* SCSI protocol the tport is providing */ - u8 tport_proto_id; - /* Binary World Wide unique Port Name for Vhost Target port */ - u64 tport_wwpn; - /* ASCII formatted WWPN for Vhost Target port */ - char tport_name[TCM_VHOST_NAMELEN]; - /* Returned by tcm_vhost_make_tport() */ - struct se_wwn tport_wwn; -}; - -/* - * As per request from MST, keep TCM_VHOST related ioctl defines out of - * linux/vhost.h (user-space) for now.. - */ - -#include <linux/vhost.h> - -/* - * Used by QEMU userspace to ensure a consistent vhost-scsi ABI. - * - * ABI Rev 0: July 2012 version starting point for v3.6-rc merge candidate + - * RFC-v2 vhost-scsi userspace. Add GET_ABI_VERSION ioctl usage - */ - -#define VHOST_SCSI_ABI_VERSION 0 - -struct vhost_scsi_target { - int abi_version; - char vhost_wwpn[TRANSPORT_IQN_LEN]; - unsigned short vhost_tpgt; - unsigned short reserved; -}; - -/* VHOST_SCSI specific defines */ -#define VHOST_SCSI_SET_ENDPOINT _IOW(VHOST_VIRTIO, 0x40, struct vhost_scsi_target) -#define VHOST_SCSI_CLEAR_ENDPOINT _IOW(VHOST_VIRTIO, 0x41, struct vhost_scsi_target) -/* Changing this breaks userspace. */ -#define VHOST_SCSI_GET_ABI_VERSION _IOW(VHOST_VIRTIO, 0x42, int) diff --git a/drivers/vhost/test.c b/drivers/vhost/test.c index 91d6f060aad..d9c501eaa6c 100644 --- a/drivers/vhost/test.c +++ b/drivers/vhost/test.c @@ -13,12 +13,11 @@ #include <linux/module.h> #include <linux/mutex.h> #include <linux/workqueue.h> -#include <linux/rcupdate.h> #include <linux/file.h> #include <linux/slab.h> #include "test.h" -#include "vhost.c" +#include "vhost.h" /* Max number of bytes transferred before requeueing the job. * Using this limit prevents one virtqueue from starving others. */ @@ -38,21 +37,23 @@ struct vhost_test { * read-size critical section for our kind of RCU. */ static void handle_vq(struct vhost_test *n) { - struct vhost_virtqueue *vq = &n->dev.vqs[VHOST_TEST_VQ]; + struct vhost_virtqueue *vq = &n->vqs[VHOST_TEST_VQ]; unsigned out, in; int head; size_t len, total_len = 0; void *private; - private = rcu_dereference_check(vq->private_data, 1); - if (!private) + mutex_lock(&vq->mutex); + private = vq->private_data; + if (!private) { + mutex_unlock(&vq->mutex); return; + } - mutex_lock(&vq->mutex); vhost_disable_notify(&n->dev, vq); for (;;) { - head = vhost_get_vq_desc(&n->dev, vq, vq->iov, + head = vhost_get_vq_desc(vq, vq->iov, ARRAY_SIZE(vq->iov), &out, &in, NULL, NULL); @@ -102,18 +103,20 @@ static int vhost_test_open(struct inode *inode, struct file *f) { struct vhost_test *n = kmalloc(sizeof *n, GFP_KERNEL); struct vhost_dev *dev; - int r; + struct vhost_virtqueue **vqs; if (!n) return -ENOMEM; + vqs = kmalloc(VHOST_TEST_VQ_MAX * sizeof(*vqs), GFP_KERNEL); + if (!vqs) { + kfree(n); + return -ENOMEM; + } dev = &n->dev; + vqs[VHOST_TEST_VQ] = &n->vqs[VHOST_TEST_VQ]; n->vqs[VHOST_TEST_VQ].handle_kick = handle_vq_kick; - r = vhost_dev_init(dev, n->vqs, VHOST_TEST_VQ_MAX); - if (r < 0) { - kfree(n); - return r; - } + vhost_dev_init(dev, vqs, VHOST_TEST_VQ_MAX); f->private_data = n; @@ -126,9 +129,8 @@ static void *vhost_test_stop_vq(struct vhost_test *n, void *private; mutex_lock(&vq->mutex); - private = rcu_dereference_protected(vq->private_data, - lockdep_is_held(&vq->mutex)); - rcu_assign_pointer(vq->private_data, NULL); + private = vq->private_data; + vq->private_data = NULL; mutex_unlock(&vq->mutex); return private; } @@ -140,7 +142,7 @@ static void vhost_test_stop(struct vhost_test *n, void **privatep) static void vhost_test_flush_vq(struct vhost_test *n, int index) { - vhost_poll_flush(&n->dev.vqs[index].poll); + vhost_poll_flush(&n->vqs[index].poll); } static void vhost_test_flush(struct vhost_test *n) @@ -191,9 +193,8 @@ static long vhost_test_run(struct vhost_test *n, int test) priv = test ? n : NULL; /* start polling new socket */ - oldpriv = rcu_dereference_protected(vq->private_data, - lockdep_is_held(&vq->mutex)); - rcu_assign_pointer(vq->private_data, priv); + oldpriv = vq->private_data; + vq->private_data = priv; r = vhost_init_used(&n->vqs[index]); @@ -219,13 +220,20 @@ static long vhost_test_reset_owner(struct vhost_test *n) { void *priv = NULL; long err; + struct vhost_memory *memory; + mutex_lock(&n->dev.mutex); err = vhost_dev_check_owner(&n->dev); if (err) goto done; + memory = vhost_dev_reset_owner_prepare(); + if (!memory) { + err = -ENOMEM; + goto done; + } vhost_test_stop(n, &priv); vhost_test_flush(n); - err = vhost_dev_reset_owner(&n->dev); + vhost_dev_reset_owner(&n->dev, memory); done: mutex_unlock(&n->dev.mutex); return err; @@ -233,15 +241,18 @@ done: static int vhost_test_set_features(struct vhost_test *n, u64 features) { + struct vhost_virtqueue *vq; + mutex_lock(&n->dev.mutex); if ((features & (1 << VHOST_F_LOG_ALL)) && !vhost_log_access_ok(&n->dev)) { mutex_unlock(&n->dev.mutex); return -EFAULT; } - n->dev.acked_features = features; - smp_wmb(); - vhost_test_flush(n); + vq = &n->vqs[VHOST_TEST_VQ]; + mutex_lock(&vq->mutex); + vq->acked_features = features; + mutex_unlock(&vq->mutex); mutex_unlock(&n->dev.mutex); return 0; } @@ -261,21 +272,23 @@ static long vhost_test_ioctl(struct file *f, unsigned int ioctl, return -EFAULT; return vhost_test_run(n, test); case VHOST_GET_FEATURES: - features = VHOST_NET_FEATURES; + features = VHOST_FEATURES; if (copy_to_user(featurep, &features, sizeof features)) return -EFAULT; return 0; case VHOST_SET_FEATURES: if (copy_from_user(&features, featurep, sizeof features)) return -EFAULT; - if (features & ~VHOST_NET_FEATURES) + if (features & ~VHOST_FEATURES) return -EOPNOTSUPP; return vhost_test_set_features(n, features); case VHOST_RESET_OWNER: return vhost_test_reset_owner(n); default: mutex_lock(&n->dev.mutex); - r = vhost_dev_ioctl(&n->dev, ioctl, arg); + r = vhost_dev_ioctl(&n->dev, ioctl, argp); + if (r == -ENOIOCTLCMD) + r = vhost_vring_ioctl(&n->dev, ioctl, argp); vhost_test_flush(n); mutex_unlock(&n->dev.mutex); return r; diff --git a/drivers/vhost/vhost.c b/drivers/vhost/vhost.c index 34389f75fe6..c90f4374442 100644 --- a/drivers/vhost/vhost.c +++ b/drivers/vhost/vhost.c @@ -13,18 +13,18 @@ #include <linux/eventfd.h> #include <linux/vhost.h> -#include <linux/virtio_net.h> +#include <linux/uio.h> #include <linux/mm.h> #include <linux/mmu_context.h> #include <linux/miscdevice.h> #include <linux/mutex.h> -#include <linux/rcupdate.h> #include <linux/poll.h> #include <linux/file.h> #include <linux/highmem.h> #include <linux/slab.h> #include <linux/kthread.h> #include <linux/cgroup.h> +#include <linux/module.h> #include "vhost.h" @@ -33,8 +33,6 @@ enum { VHOST_MEMORY_F_LOG = 0x1, }; -static unsigned vhost_zcopy_mask __read_mostly; - #define vhost_used_event(vq) ((u16 __user *)&vq->avail->ring[vq->num]) #define vhost_avail_event(vq) ((u16 __user *)&vq->used->ring[vq->num]) @@ -68,6 +66,7 @@ void vhost_work_init(struct vhost_work *work, vhost_work_fn_t fn) work->flushing = 0; work->queue_seq = work->done_seq = 0; } +EXPORT_SYMBOL_GPL(vhost_work_init); /* Init poll structure */ void vhost_poll_init(struct vhost_poll *poll, vhost_work_fn_t fn, @@ -77,27 +76,45 @@ void vhost_poll_init(struct vhost_poll *poll, vhost_work_fn_t fn, init_poll_funcptr(&poll->table, vhost_poll_func); poll->mask = mask; poll->dev = dev; + poll->wqh = NULL; vhost_work_init(&poll->work, fn); } +EXPORT_SYMBOL_GPL(vhost_poll_init); /* Start polling a file. We add ourselves to file's wait queue. The caller must * keep a reference to a file until after vhost_poll_stop is called. */ -void vhost_poll_start(struct vhost_poll *poll, struct file *file) +int vhost_poll_start(struct vhost_poll *poll, struct file *file) { unsigned long mask; + int ret = 0; + + if (poll->wqh) + return 0; mask = file->f_op->poll(file, &poll->table); if (mask) vhost_poll_wakeup(&poll->wait, 0, 0, (void *)mask); + if (mask & POLLERR) { + if (poll->wqh) + remove_wait_queue(poll->wqh, &poll->wait); + ret = -EINVAL; + } + + return ret; } +EXPORT_SYMBOL_GPL(vhost_poll_start); /* Stop polling a file. After this function returns, it becomes safe to drop the * file reference. You must also flush afterwards. */ void vhost_poll_stop(struct vhost_poll *poll) { - remove_wait_queue(poll->wqh, &poll->wait); + if (poll->wqh) { + remove_wait_queue(poll->wqh, &poll->wait); + poll->wqh = NULL; + } } +EXPORT_SYMBOL_GPL(vhost_poll_stop); static bool vhost_work_seq_done(struct vhost_dev *dev, struct vhost_work *work, unsigned seq) @@ -110,7 +127,7 @@ static bool vhost_work_seq_done(struct vhost_dev *dev, struct vhost_work *work, return left <= 0; } -static void vhost_work_flush(struct vhost_dev *dev, struct vhost_work *work) +void vhost_work_flush(struct vhost_dev *dev, struct vhost_work *work) { unsigned seq; int flushing; @@ -125,6 +142,7 @@ static void vhost_work_flush(struct vhost_dev *dev, struct vhost_work *work) spin_unlock_irq(&dev->work_lock); BUG_ON(flushing < 0); } +EXPORT_SYMBOL_GPL(vhost_work_flush); /* Flush any work that has been scheduled. When calling this, don't hold any * locks that are also used by the callback. */ @@ -132,6 +150,7 @@ void vhost_poll_flush(struct vhost_poll *poll) { vhost_work_flush(poll->dev, &poll->work); } +EXPORT_SYMBOL_GPL(vhost_poll_flush); void vhost_work_queue(struct vhost_dev *dev, struct vhost_work *work) { @@ -141,15 +160,19 @@ void vhost_work_queue(struct vhost_dev *dev, struct vhost_work *work) if (list_empty(&work->node)) { list_add_tail(&work->node, &dev->work_list); work->queue_seq++; + spin_unlock_irqrestore(&dev->work_lock, flags); wake_up_process(dev->worker); + } else { + spin_unlock_irqrestore(&dev->work_lock, flags); } - spin_unlock_irqrestore(&dev->work_lock, flags); } +EXPORT_SYMBOL_GPL(vhost_work_queue); void vhost_poll_queue(struct vhost_poll *poll) { vhost_work_queue(poll->dev, &poll->work); } +EXPORT_SYMBOL_GPL(vhost_poll_queue); static void vhost_vq_reset(struct vhost_dev *dev, struct vhost_virtqueue *vq) @@ -166,9 +189,8 @@ static void vhost_vq_reset(struct vhost_dev *dev, vq->used_flags = 0; vq->log_used = false; vq->log_addr = -1ull; - vq->vhost_hlen = 0; - vq->sock_hlen = 0; vq->private_data = NULL; + vq->acked_features = 0; vq->log_base = NULL; vq->error_ctx = NULL; vq->error = NULL; @@ -176,9 +198,7 @@ static void vhost_vq_reset(struct vhost_dev *dev, vq->call_ctx = NULL; vq->call = NULL; vq->log_ctx = NULL; - vq->upend_idx = 0; - vq->done_idx = 0; - vq->ubufs = NULL; + vq->memory = NULL; } static int vhost_worker(void *data) @@ -238,43 +258,28 @@ static void vhost_vq_free_iovecs(struct vhost_virtqueue *vq) vq->log = NULL; kfree(vq->heads); vq->heads = NULL; - kfree(vq->ubuf_info); - vq->ubuf_info = NULL; -} - -void vhost_enable_zcopy(int vq) -{ - vhost_zcopy_mask |= 0x1 << vq; } /* Helper to allocate iovec buffers for all vqs. */ static long vhost_dev_alloc_iovecs(struct vhost_dev *dev) { + struct vhost_virtqueue *vq; int i; - bool zcopy; for (i = 0; i < dev->nvqs; ++i) { - dev->vqs[i].indirect = kmalloc(sizeof *dev->vqs[i].indirect * - UIO_MAXIOV, GFP_KERNEL); - dev->vqs[i].log = kmalloc(sizeof *dev->vqs[i].log * UIO_MAXIOV, - GFP_KERNEL); - dev->vqs[i].heads = kmalloc(sizeof *dev->vqs[i].heads * - UIO_MAXIOV, GFP_KERNEL); - zcopy = vhost_zcopy_mask & (0x1 << i); - if (zcopy) - dev->vqs[i].ubuf_info = - kmalloc(sizeof *dev->vqs[i].ubuf_info * - UIO_MAXIOV, GFP_KERNEL); - if (!dev->vqs[i].indirect || !dev->vqs[i].log || - !dev->vqs[i].heads || - (zcopy && !dev->vqs[i].ubuf_info)) + vq = dev->vqs[i]; + vq->indirect = kmalloc(sizeof *vq->indirect * UIO_MAXIOV, + GFP_KERNEL); + vq->log = kmalloc(sizeof *vq->log * UIO_MAXIOV, GFP_KERNEL); + vq->heads = kmalloc(sizeof *vq->heads * UIO_MAXIOV, GFP_KERNEL); + if (!vq->indirect || !vq->log || !vq->heads) goto err_nomem; } return 0; err_nomem: for (; i >= 0; --i) - vhost_vq_free_iovecs(&dev->vqs[i]); + vhost_vq_free_iovecs(dev->vqs[i]); return -ENOMEM; } @@ -283,12 +288,13 @@ static void vhost_dev_free_iovecs(struct vhost_dev *dev) int i; for (i = 0; i < dev->nvqs; ++i) - vhost_vq_free_iovecs(&dev->vqs[i]); + vhost_vq_free_iovecs(dev->vqs[i]); } -long vhost_dev_init(struct vhost_dev *dev, - struct vhost_virtqueue *vqs, int nvqs) +void vhost_dev_init(struct vhost_dev *dev, + struct vhost_virtqueue **vqs, int nvqs) { + struct vhost_virtqueue *vq; int i; dev->vqs = vqs; @@ -303,20 +309,19 @@ long vhost_dev_init(struct vhost_dev *dev, dev->worker = NULL; for (i = 0; i < dev->nvqs; ++i) { - dev->vqs[i].log = NULL; - dev->vqs[i].indirect = NULL; - dev->vqs[i].heads = NULL; - dev->vqs[i].ubuf_info = NULL; - dev->vqs[i].dev = dev; - mutex_init(&dev->vqs[i].mutex); - vhost_vq_reset(dev, dev->vqs + i); - if (dev->vqs[i].handle_kick) - vhost_poll_init(&dev->vqs[i].poll, - dev->vqs[i].handle_kick, POLLIN, dev); + vq = dev->vqs[i]; + vq->log = NULL; + vq->indirect = NULL; + vq->heads = NULL; + vq->dev = dev; + mutex_init(&vq->mutex); + vhost_vq_reset(dev, vq); + if (vq->handle_kick) + vhost_poll_init(&vq->poll, vq->handle_kick, + POLLIN, dev); } - - return 0; } +EXPORT_SYMBOL_GPL(vhost_dev_init); /* Caller should have device mutex */ long vhost_dev_check_owner(struct vhost_dev *dev) @@ -324,6 +329,7 @@ long vhost_dev_check_owner(struct vhost_dev *dev) /* Are you the owner? If not, I don't think you mean to do that */ return dev->mm == current->mm ? 0 : -EPERM; } +EXPORT_SYMBOL_GPL(vhost_dev_check_owner); struct vhost_attach_cgroups_struct { struct vhost_work work; @@ -351,13 +357,20 @@ static int vhost_attach_cgroups(struct vhost_dev *dev) } /* Caller should have device mutex */ -static long vhost_dev_set_owner(struct vhost_dev *dev) +bool vhost_dev_has_owner(struct vhost_dev *dev) +{ + return dev->mm; +} +EXPORT_SYMBOL_GPL(vhost_dev_has_owner); + +/* Caller should have device mutex */ +long vhost_dev_set_owner(struct vhost_dev *dev) { struct task_struct *worker; int err; /* Is there an owner already? */ - if (dev->mm) { + if (vhost_dev_has_owner(dev)) { err = -EBUSY; goto err_mm; } @@ -392,35 +405,44 @@ err_worker: err_mm: return err; } +EXPORT_SYMBOL_GPL(vhost_dev_set_owner); -/* Caller should have device mutex */ -long vhost_dev_reset_owner(struct vhost_dev *dev) +struct vhost_memory *vhost_dev_reset_owner_prepare(void) { - struct vhost_memory *memory; + return kmalloc(offsetof(struct vhost_memory, regions), GFP_KERNEL); +} +EXPORT_SYMBOL_GPL(vhost_dev_reset_owner_prepare); - /* Restore memory to default empty mapping. */ - memory = kmalloc(offsetof(struct vhost_memory, regions), GFP_KERNEL); - if (!memory) - return -ENOMEM; +/* Caller should have device mutex */ +void vhost_dev_reset_owner(struct vhost_dev *dev, struct vhost_memory *memory) +{ + int i; vhost_dev_cleanup(dev, true); + /* Restore memory to default empty mapping. */ memory->nregions = 0; - RCU_INIT_POINTER(dev->memory, memory); - return 0; + dev->memory = memory; + /* We don't need VQ locks below since vhost_dev_cleanup makes sure + * VQs aren't running. + */ + for (i = 0; i < dev->nvqs; ++i) + dev->vqs[i]->memory = memory; } +EXPORT_SYMBOL_GPL(vhost_dev_reset_owner); void vhost_dev_stop(struct vhost_dev *dev) { int i; for (i = 0; i < dev->nvqs; ++i) { - if (dev->vqs[i].kick && dev->vqs[i].handle_kick) { - vhost_poll_stop(&dev->vqs[i].poll); - vhost_poll_flush(&dev->vqs[i].poll); + if (dev->vqs[i]->kick && dev->vqs[i]->handle_kick) { + vhost_poll_stop(&dev->vqs[i]->poll); + vhost_poll_flush(&dev->vqs[i]->poll); } } } +EXPORT_SYMBOL_GPL(vhost_dev_stop); /* Caller should have device mutex if and only if locked is set */ void vhost_dev_cleanup(struct vhost_dev *dev, bool locked) @@ -428,17 +450,17 @@ void vhost_dev_cleanup(struct vhost_dev *dev, bool locked) int i; for (i = 0; i < dev->nvqs; ++i) { - if (dev->vqs[i].error_ctx) - eventfd_ctx_put(dev->vqs[i].error_ctx); - if (dev->vqs[i].error) - fput(dev->vqs[i].error); - if (dev->vqs[i].kick) - fput(dev->vqs[i].kick); - if (dev->vqs[i].call_ctx) - eventfd_ctx_put(dev->vqs[i].call_ctx); - if (dev->vqs[i].call) - fput(dev->vqs[i].call); - vhost_vq_reset(dev, dev->vqs + i); + if (dev->vqs[i]->error_ctx) + eventfd_ctx_put(dev->vqs[i]->error_ctx); + if (dev->vqs[i]->error) + fput(dev->vqs[i]->error); + if (dev->vqs[i]->kick) + fput(dev->vqs[i]->kick); + if (dev->vqs[i]->call_ctx) + eventfd_ctx_put(dev->vqs[i]->call_ctx); + if (dev->vqs[i]->call) + fput(dev->vqs[i]->call); + vhost_vq_reset(dev, dev->vqs[i]); } vhost_dev_free_iovecs(dev); if (dev->log_ctx) @@ -448,10 +470,8 @@ void vhost_dev_cleanup(struct vhost_dev *dev, bool locked) fput(dev->log_file); dev->log_file = NULL; /* No one will access memory at this point */ - kfree(rcu_dereference_protected(dev->memory, - locked == - lockdep_is_held(&dev->mutex))); - RCU_INIT_POINTER(dev->memory, NULL); + kfree(dev->memory); + dev->memory = NULL; WARN_ON(!list_empty(&dev->work_list)); if (dev->worker) { kthread_stop(dev->worker); @@ -461,6 +481,7 @@ void vhost_dev_cleanup(struct vhost_dev *dev, bool locked) mmput(dev->mm); dev->mm = NULL; } +EXPORT_SYMBOL_GPL(vhost_dev_cleanup); static int log_access_ok(void __user *log_base, u64 addr, unsigned long sz) { @@ -509,26 +530,28 @@ static int memory_access_ok(struct vhost_dev *d, struct vhost_memory *mem, for (i = 0; i < d->nvqs; ++i) { int ok; - mutex_lock(&d->vqs[i].mutex); + bool log; + + mutex_lock(&d->vqs[i]->mutex); + log = log_all || vhost_has_feature(d->vqs[i], VHOST_F_LOG_ALL); /* If ring is inactive, will check when it's enabled. */ - if (d->vqs[i].private_data) - ok = vq_memory_access_ok(d->vqs[i].log_base, mem, - log_all); + if (d->vqs[i]->private_data) + ok = vq_memory_access_ok(d->vqs[i]->log_base, mem, log); else ok = 1; - mutex_unlock(&d->vqs[i].mutex); + mutex_unlock(&d->vqs[i]->mutex); if (!ok) return 0; } return 1; } -static int vq_access_ok(struct vhost_dev *d, unsigned int num, +static int vq_access_ok(struct vhost_virtqueue *vq, unsigned int num, struct vring_desc __user *desc, struct vring_avail __user *avail, struct vring_used __user *used) { - size_t s = vhost_has_feature(d, VIRTIO_RING_F_EVENT_IDX) ? 2 : 0; + size_t s = vhost_has_feature(vq, VIRTIO_RING_F_EVENT_IDX) ? 2 : 0; return access_ok(VERIFY_READ, desc, num * sizeof *desc) && access_ok(VERIFY_READ, avail, sizeof *avail + num * sizeof *avail->ring + s) && @@ -540,25 +563,19 @@ static int vq_access_ok(struct vhost_dev *d, unsigned int num, /* Caller should have device mutex but not vq mutex */ int vhost_log_access_ok(struct vhost_dev *dev) { - struct vhost_memory *mp; - - mp = rcu_dereference_protected(dev->memory, - lockdep_is_held(&dev->mutex)); - return memory_access_ok(dev, mp, 1); + return memory_access_ok(dev, dev->memory, 1); } +EXPORT_SYMBOL_GPL(vhost_log_access_ok); /* Verify access for write logging. */ /* Caller should have vq mutex and device mutex */ -static int vq_log_access_ok(struct vhost_dev *d, struct vhost_virtqueue *vq, +static int vq_log_access_ok(struct vhost_virtqueue *vq, void __user *log_base) { - struct vhost_memory *mp; - size_t s = vhost_has_feature(d, VIRTIO_RING_F_EVENT_IDX) ? 2 : 0; + size_t s = vhost_has_feature(vq, VIRTIO_RING_F_EVENT_IDX) ? 2 : 0; - mp = rcu_dereference_protected(vq->dev->memory, - lockdep_is_held(&vq->mutex)); - return vq_memory_access_ok(log_base, mp, - vhost_has_feature(vq->dev, VHOST_F_LOG_ALL)) && + return vq_memory_access_ok(log_base, vq->memory, + vhost_has_feature(vq, VHOST_F_LOG_ALL)) && (!vq->log_used || log_access_ok(log_base, vq->log_addr, sizeof *vq->used + vq->num * sizeof *vq->used->ring + s)); @@ -568,14 +585,16 @@ static int vq_log_access_ok(struct vhost_dev *d, struct vhost_virtqueue *vq, /* Caller should have vq mutex and device mutex */ int vhost_vq_access_ok(struct vhost_virtqueue *vq) { - return vq_access_ok(vq->dev, vq->num, vq->desc, vq->avail, vq->used) && - vq_log_access_ok(vq->dev, vq, vq->log_base); + return vq_access_ok(vq, vq->num, vq->desc, vq->avail, vq->used) && + vq_log_access_ok(vq, vq->log_base); } +EXPORT_SYMBOL_GPL(vhost_vq_access_ok); static long vhost_set_memory(struct vhost_dev *d, struct vhost_memory __user *m) { struct vhost_memory mem, *newmem, *oldmem; unsigned long size = offsetof(struct vhost_memory, regions); + int i; if (copy_from_user(&mem, m, size)) return -EFAULT; @@ -594,15 +613,19 @@ static long vhost_set_memory(struct vhost_dev *d, struct vhost_memory __user *m) return -EFAULT; } - if (!memory_access_ok(d, newmem, - vhost_has_feature(d, VHOST_F_LOG_ALL))) { + if (!memory_access_ok(d, newmem, 0)) { kfree(newmem); return -EFAULT; } - oldmem = rcu_dereference_protected(d->memory, - lockdep_is_held(&d->mutex)); - rcu_assign_pointer(d->memory, newmem); - synchronize_rcu(); + oldmem = d->memory; + d->memory = newmem; + + /* All memory accesses are done under some VQ mutex. */ + for (i = 0; i < d->nvqs; ++i) { + mutex_lock(&d->vqs[i]->mutex); + d->vqs[i]->memory = newmem; + mutex_unlock(&d->vqs[i]->mutex); + } kfree(oldmem); return 0; } @@ -626,7 +649,7 @@ long vhost_vring_ioctl(struct vhost_dev *d, int ioctl, void __user *argp) if (idx >= d->nvqs) return -ENOBUFS; - vq = d->vqs + idx; + vq = d->vqs[idx]; mutex_lock(&vq->mutex); @@ -701,7 +724,7 @@ long vhost_vring_ioctl(struct vhost_dev *d, int ioctl, void __user *argp) * If it is not, we don't as size might not have been setup. * We will verify when backend is configured. */ if (vq->private_data) { - if (!vq_access_ok(d, vq->num, + if (!vq_access_ok(vq, vq->num, (void __user *)(unsigned long)a.desc_user_addr, (void __user *)(unsigned long)a.avail_user_addr, (void __user *)(unsigned long)a.used_user_addr)) { @@ -792,7 +815,7 @@ long vhost_vring_ioctl(struct vhost_dev *d, int ioctl, void __user *argp) fput(filep); if (pollstart && vq->handle_kick) - vhost_poll_start(&vq->poll, vq->kick); + r = vhost_poll_start(&vq->poll, vq->kick); mutex_unlock(&vq->mutex); @@ -800,6 +823,7 @@ long vhost_vring_ioctl(struct vhost_dev *d, int ioctl, void __user *argp) vhost_poll_flush(&vq->poll); return r; } +EXPORT_SYMBOL_GPL(vhost_vring_ioctl); /* Caller must have device mutex */ long vhost_dev_ioctl(struct vhost_dev *d, unsigned int ioctl, void __user *argp) @@ -837,10 +861,10 @@ long vhost_dev_ioctl(struct vhost_dev *d, unsigned int ioctl, void __user *argp) for (i = 0; i < d->nvqs; ++i) { struct vhost_virtqueue *vq; void __user *base = (void __user *)(unsigned long)p; - vq = d->vqs + i; + vq = d->vqs[i]; mutex_lock(&vq->mutex); /* If ring is inactive, will check when it's enabled. */ - if (vq->private_data && !vq_log_access_ok(d, vq, base)) + if (vq->private_data && !vq_log_access_ok(vq, base)) r = -EFAULT; else vq->log_base = base; @@ -864,9 +888,9 @@ long vhost_dev_ioctl(struct vhost_dev *d, unsigned int ioctl, void __user *argp) } else filep = eventfp; for (i = 0; i < d->nvqs; ++i) { - mutex_lock(&d->vqs[i].mutex); - d->vqs[i].log_ctx = d->log_ctx; - mutex_unlock(&d->vqs[i].mutex); + mutex_lock(&d->vqs[i]->mutex); + d->vqs[i]->log_ctx = d->log_ctx; + mutex_unlock(&d->vqs[i]->mutex); } if (ctx) eventfd_ctx_put(ctx); @@ -880,6 +904,7 @@ long vhost_dev_ioctl(struct vhost_dev *d, unsigned int ioctl, void __user *argp) done: return r; } +EXPORT_SYMBOL_GPL(vhost_dev_ioctl); static const struct vhost_memory_region *find_region(struct vhost_memory *mem, __u64 addr, __u32 len) @@ -971,6 +996,7 @@ int vhost_log_write(struct vhost_virtqueue *vq, struct vhost_log *log, BUG(); return 0; } +EXPORT_SYMBOL_GPL(vhost_log_write); static int vhost_update_used_flags(struct vhost_virtqueue *vq) { @@ -1022,8 +1048,9 @@ int vhost_init_used(struct vhost_virtqueue *vq) vq->signalled_used_valid = false; return get_user(vq->last_used_idx, &vq->used->idx); } +EXPORT_SYMBOL_GPL(vhost_init_used); -static int translate_desc(struct vhost_dev *dev, u64 addr, u32 len, +static int translate_desc(struct vhost_virtqueue *vq, u64 addr, u32 len, struct iovec iov[], int iov_size) { const struct vhost_memory_region *reg; @@ -1032,9 +1059,7 @@ static int translate_desc(struct vhost_dev *dev, u64 addr, u32 len, u64 s = 0; int ret = 0; - rcu_read_lock(); - - mem = rcu_dereference(dev->memory); + mem = vq->memory; while ((u64)len > s) { u64 size; if (unlikely(ret >= iov_size)) { @@ -1056,7 +1081,6 @@ static int translate_desc(struct vhost_dev *dev, u64 addr, u32 len, ++ret; } - rcu_read_unlock(); return ret; } @@ -1081,7 +1105,7 @@ static unsigned next_desc(struct vring_desc *desc) return next; } -static int get_indirect(struct vhost_dev *dev, struct vhost_virtqueue *vq, +static int get_indirect(struct vhost_virtqueue *vq, struct iovec iov[], unsigned int iov_size, unsigned int *out_num, unsigned int *in_num, struct vhost_log *log, unsigned int *log_num, @@ -1100,7 +1124,7 @@ static int get_indirect(struct vhost_dev *dev, struct vhost_virtqueue *vq, return -EINVAL; } - ret = translate_desc(dev, indirect->addr, indirect->len, vq->indirect, + ret = translate_desc(vq, indirect->addr, indirect->len, vq->indirect, UIO_MAXIOV); if (unlikely(ret < 0)) { vq_err(vq, "Translation failure %d in indirect.\n", ret); @@ -1140,7 +1164,7 @@ static int get_indirect(struct vhost_dev *dev, struct vhost_virtqueue *vq, return -EINVAL; } - ret = translate_desc(dev, desc.addr, desc.len, iov + iov_count, + ret = translate_desc(vq, desc.addr, desc.len, iov + iov_count, iov_size - iov_count); if (unlikely(ret < 0)) { vq_err(vq, "Translation failure %d indirect idx %d\n", @@ -1177,7 +1201,7 @@ static int get_indirect(struct vhost_dev *dev, struct vhost_virtqueue *vq, * This function returns the descriptor number found, or vq->num (which is * never a valid descriptor number) if none was found. A negative code is * returned on error. */ -int vhost_get_vq_desc(struct vhost_dev *dev, struct vhost_virtqueue *vq, +int vhost_get_vq_desc(struct vhost_virtqueue *vq, struct iovec iov[], unsigned int iov_size, unsigned int *out_num, unsigned int *in_num, struct vhost_log *log, unsigned int *log_num) @@ -1251,7 +1275,7 @@ int vhost_get_vq_desc(struct vhost_dev *dev, struct vhost_virtqueue *vq, return -EFAULT; } if (desc.flags & VRING_DESC_F_INDIRECT) { - ret = get_indirect(dev, vq, iov, iov_size, + ret = get_indirect(vq, iov, iov_size, out_num, in_num, log, log_num, &desc); if (unlikely(ret < 0)) { @@ -1262,7 +1286,7 @@ int vhost_get_vq_desc(struct vhost_dev *dev, struct vhost_virtqueue *vq, continue; } - ret = translate_desc(dev, desc.addr, desc.len, iov + iov_count, + ret = translate_desc(vq, desc.addr, desc.len, iov + iov_count, iov_size - iov_count); if (unlikely(ret < 0)) { vq_err(vq, "Translation failure %d descriptor idx %d\n", @@ -1298,60 +1322,24 @@ int vhost_get_vq_desc(struct vhost_dev *dev, struct vhost_virtqueue *vq, BUG_ON(!(vq->used_flags & VRING_USED_F_NO_NOTIFY)); return head; } +EXPORT_SYMBOL_GPL(vhost_get_vq_desc); /* Reverse the effect of vhost_get_vq_desc. Useful for error handling. */ void vhost_discard_vq_desc(struct vhost_virtqueue *vq, int n) { vq->last_avail_idx -= n; } +EXPORT_SYMBOL_GPL(vhost_discard_vq_desc); /* After we've used one of their buffers, we tell them about it. We'll then * want to notify the guest, using eventfd. */ int vhost_add_used(struct vhost_virtqueue *vq, unsigned int head, int len) { - struct vring_used_elem __user *used; + struct vring_used_elem heads = { head, len }; - /* The virtqueue contains a ring of used buffers. Get a pointer to the - * next entry in that used ring. */ - used = &vq->used->ring[vq->last_used_idx % vq->num]; - if (__put_user(head, &used->id)) { - vq_err(vq, "Failed to write used id"); - return -EFAULT; - } - if (__put_user(len, &used->len)) { - vq_err(vq, "Failed to write used len"); - return -EFAULT; - } - /* Make sure buffer is written before we update index. */ - smp_wmb(); - if (__put_user(vq->last_used_idx + 1, &vq->used->idx)) { - vq_err(vq, "Failed to increment used idx"); - return -EFAULT; - } - if (unlikely(vq->log_used)) { - /* Make sure data is seen before log. */ - smp_wmb(); - /* Log used ring entry write. */ - log_write(vq->log_base, - vq->log_addr + - ((void __user *)used - (void __user *)vq->used), - sizeof *used); - /* Log used index update. */ - log_write(vq->log_base, - vq->log_addr + offsetof(struct vring_used, idx), - sizeof vq->used->idx); - if (vq->log_ctx) - eventfd_signal(vq->log_ctx, 1); - } - vq->last_used_idx++; - /* If the driver never bothers to signal in a very long while, - * used index might wrap around. If that happens, invalidate - * signalled_used index we stored. TODO: make sure driver - * signals at least once in 2^16 and remove this. */ - if (unlikely(vq->last_used_idx == vq->signalled_used)) - vq->signalled_used_valid = false; - return 0; + return vhost_add_used_n(vq, &heads, 1); } +EXPORT_SYMBOL_GPL(vhost_add_used); static int __vhost_add_used_n(struct vhost_virtqueue *vq, struct vring_used_elem *heads, @@ -1363,7 +1351,16 @@ static int __vhost_add_used_n(struct vhost_virtqueue *vq, start = vq->last_used_idx % vq->num; used = vq->used->ring + start; - if (__copy_to_user(used, heads, count * sizeof *used)) { + if (count == 1) { + if (__put_user(heads[0].id, &used->id)) { + vq_err(vq, "Failed to write used id"); + return -EFAULT; + } + if (__put_user(heads[0].len, &used->len)) { + vq_err(vq, "Failed to write used len"); + return -EFAULT; + } + } else if (__copy_to_user(used, heads, count * sizeof *used)) { vq_err(vq, "Failed to write used"); return -EFAULT; } @@ -1421,6 +1418,7 @@ int vhost_add_used_n(struct vhost_virtqueue *vq, struct vring_used_elem *heads, } return r; } +EXPORT_SYMBOL_GPL(vhost_add_used_n); static bool vhost_notify(struct vhost_dev *dev, struct vhost_virtqueue *vq) { @@ -1431,11 +1429,11 @@ static bool vhost_notify(struct vhost_dev *dev, struct vhost_virtqueue *vq) * interrupts. */ smp_mb(); - if (vhost_has_feature(dev, VIRTIO_F_NOTIFY_ON_EMPTY) && + if (vhost_has_feature(vq, VIRTIO_F_NOTIFY_ON_EMPTY) && unlikely(vq->avail_idx == vq->last_avail_idx)) return true; - if (!vhost_has_feature(dev, VIRTIO_RING_F_EVENT_IDX)) { + if (!vhost_has_feature(vq, VIRTIO_RING_F_EVENT_IDX)) { __u16 flags; if (__get_user(flags, &vq->avail->flags)) { vq_err(vq, "Failed to get flags"); @@ -1465,6 +1463,7 @@ void vhost_signal(struct vhost_dev *dev, struct vhost_virtqueue *vq) if (vq->call_ctx && vhost_notify(dev, vq)) eventfd_signal(vq->call_ctx, 1); } +EXPORT_SYMBOL_GPL(vhost_signal); /* And here's the combo meal deal. Supersize me! */ void vhost_add_used_and_signal(struct vhost_dev *dev, @@ -1474,6 +1473,7 @@ void vhost_add_used_and_signal(struct vhost_dev *dev, vhost_add_used(vq, head, len); vhost_signal(dev, vq); } +EXPORT_SYMBOL_GPL(vhost_add_used_and_signal); /* multi-buffer version of vhost_add_used_and_signal */ void vhost_add_used_and_signal_n(struct vhost_dev *dev, @@ -1483,6 +1483,7 @@ void vhost_add_used_and_signal_n(struct vhost_dev *dev, vhost_add_used_n(vq, heads, count); vhost_signal(dev, vq); } +EXPORT_SYMBOL_GPL(vhost_add_used_and_signal_n); /* OK, now we need to know about added descriptors. */ bool vhost_enable_notify(struct vhost_dev *dev, struct vhost_virtqueue *vq) @@ -1493,7 +1494,7 @@ bool vhost_enable_notify(struct vhost_dev *dev, struct vhost_virtqueue *vq) if (!(vq->used_flags & VRING_USED_F_NO_NOTIFY)) return false; vq->used_flags &= ~VRING_USED_F_NO_NOTIFY; - if (!vhost_has_feature(dev, VIRTIO_RING_F_EVENT_IDX)) { + if (!vhost_has_feature(vq, VIRTIO_RING_F_EVENT_IDX)) { r = vhost_update_used_flags(vq); if (r) { vq_err(vq, "Failed to enable notification at %p: %d\n", @@ -1520,6 +1521,7 @@ bool vhost_enable_notify(struct vhost_dev *dev, struct vhost_virtqueue *vq) return avail_idx != vq->avail_idx; } +EXPORT_SYMBOL_GPL(vhost_enable_notify); /* We don't need to be notified again. */ void vhost_disable_notify(struct vhost_dev *dev, struct vhost_virtqueue *vq) @@ -1529,45 +1531,28 @@ void vhost_disable_notify(struct vhost_dev *dev, struct vhost_virtqueue *vq) if (vq->used_flags & VRING_USED_F_NO_NOTIFY) return; vq->used_flags |= VRING_USED_F_NO_NOTIFY; - if (!vhost_has_feature(dev, VIRTIO_RING_F_EVENT_IDX)) { + if (!vhost_has_feature(vq, VIRTIO_RING_F_EVENT_IDX)) { r = vhost_update_used_flags(vq); if (r) vq_err(vq, "Failed to enable notification at %p: %d\n", &vq->used->flags, r); } } +EXPORT_SYMBOL_GPL(vhost_disable_notify); -static void vhost_zerocopy_done_signal(struct kref *kref) +static int __init vhost_init(void) { - struct vhost_ubuf_ref *ubufs = container_of(kref, struct vhost_ubuf_ref, - kref); - wake_up(&ubufs->wait); + return 0; } -struct vhost_ubuf_ref *vhost_ubuf_alloc(struct vhost_virtqueue *vq, - bool zcopy) +static void __exit vhost_exit(void) { - struct vhost_ubuf_ref *ubufs; - /* No zero copy backend? Nothing to count. */ - if (!zcopy) - return NULL; - ubufs = kmalloc(sizeof *ubufs, GFP_KERNEL); - if (!ubufs) - return ERR_PTR(-ENOMEM); - kref_init(&ubufs->kref); - init_waitqueue_head(&ubufs->wait); - ubufs->vq = vq; - return ubufs; } -void vhost_ubuf_put(struct vhost_ubuf_ref *ubufs) -{ - kref_put(&ubufs->kref, vhost_zerocopy_done_signal); -} +module_init(vhost_init); +module_exit(vhost_exit); -void vhost_ubuf_put_and_wait(struct vhost_ubuf_ref *ubufs) -{ - kref_put(&ubufs->kref, vhost_zerocopy_done_signal); - wait_event(ubufs->wait, !atomic_read(&ubufs->kref.refcount)); - kfree(ubufs); -} +MODULE_VERSION("0.0.1"); +MODULE_LICENSE("GPL v2"); +MODULE_AUTHOR("Michael S. Tsirkin"); +MODULE_DESCRIPTION("Host kernel accelerator for virtio"); diff --git a/drivers/vhost/vhost.h b/drivers/vhost/vhost.h index 2639c58b23a..3eda654b8f5 100644 --- a/drivers/vhost/vhost.h +++ b/drivers/vhost/vhost.h @@ -42,10 +42,12 @@ void vhost_work_queue(struct vhost_dev *dev, struct vhost_work *work); void vhost_poll_init(struct vhost_poll *poll, vhost_work_fn_t fn, unsigned long mask, struct vhost_dev *dev); -void vhost_poll_start(struct vhost_poll *poll, struct file *file); +int vhost_poll_start(struct vhost_poll *poll, struct file *file); void vhost_poll_stop(struct vhost_poll *poll); void vhost_poll_flush(struct vhost_poll *poll); void vhost_poll_queue(struct vhost_poll *poll); +void vhost_work_flush(struct vhost_dev *dev, struct vhost_work *work); +long vhost_vring_ioctl(struct vhost_dev *d, int ioctl, void __user *argp); struct vhost_log { u64 addr; @@ -54,18 +56,6 @@ struct vhost_log { struct vhost_virtqueue; -struct vhost_ubuf_ref { - struct kref kref; - wait_queue_head_t wait; - struct vhost_virtqueue *vq; -}; - -struct vhost_ubuf_ref *vhost_ubuf_alloc(struct vhost_virtqueue *, bool zcopy); -void vhost_ubuf_put(struct vhost_ubuf_ref *); -void vhost_ubuf_put_and_wait(struct vhost_ubuf_ref *); - -struct ubuf_info; - /* The virtqueue structure describes a queue attached to a device. */ struct vhost_virtqueue { struct vhost_dev *dev; @@ -111,46 +101,22 @@ struct vhost_virtqueue { u64 log_addr; struct iovec iov[UIO_MAXIOV]; - /* hdr is used to store the virtio header. - * Since each iovec has >= 1 byte length, we never need more than - * header length entries to store the header. */ - struct iovec hdr[sizeof(struct virtio_net_hdr_mrg_rxbuf)]; struct iovec *indirect; - size_t vhost_hlen; - size_t sock_hlen; struct vring_used_elem *heads; - /* We use a kind of RCU to access private pointer. - * All readers access it from worker, which makes it possible to - * flush the vhost_work instead of synchronize_rcu. Therefore readers do - * not need to call rcu_read_lock/rcu_read_unlock: the beginning of - * vhost_work execution acts instead of rcu_read_lock() and the end of - * vhost_work execution acts instead of rcu_read_unlock(). - * Writers use virtqueue mutex. */ - void __rcu *private_data; + /* Protected by virtqueue mutex. */ + struct vhost_memory *memory; + void *private_data; + unsigned acked_features; /* Log write descriptors */ void __user *log_base; struct vhost_log *log; - /* vhost zerocopy support fields below: */ - /* last used idx for outstanding DMA zerocopy buffers */ - int upend_idx; - /* first used idx for DMA done zerocopy buffers */ - int done_idx; - /* an array of userspace buffers info */ - struct ubuf_info *ubuf_info; - /* Reference counting for outstanding ubufs. - * Protected by vq mutex. Writers must also take device mutex. */ - struct vhost_ubuf_ref *ubufs; }; struct vhost_dev { - /* Readers use RCU to access memory table pointer - * log base pointer and features. - * Writers use mutex below.*/ - struct vhost_memory __rcu *memory; + struct vhost_memory *memory; struct mm_struct *mm; struct mutex mutex; - unsigned acked_features; - struct vhost_virtqueue *vqs; + struct vhost_virtqueue **vqs; int nvqs; struct file *log_file; struct eventfd_ctx *log_ctx; @@ -159,9 +125,12 @@ struct vhost_dev { struct task_struct *worker; }; -long vhost_dev_init(struct vhost_dev *, struct vhost_virtqueue *vqs, int nvqs); +void vhost_dev_init(struct vhost_dev *, struct vhost_virtqueue **vqs, int nvqs); +long vhost_dev_set_owner(struct vhost_dev *dev); +bool vhost_dev_has_owner(struct vhost_dev *dev); long vhost_dev_check_owner(struct vhost_dev *); -long vhost_dev_reset_owner(struct vhost_dev *); +struct vhost_memory *vhost_dev_reset_owner_prepare(void); +void vhost_dev_reset_owner(struct vhost_dev *, struct vhost_memory *); void vhost_dev_cleanup(struct vhost_dev *, bool locked); void vhost_dev_stop(struct vhost_dev *); long vhost_dev_ioctl(struct vhost_dev *, unsigned int ioctl, void __user *argp); @@ -169,7 +138,7 @@ long vhost_vring_ioctl(struct vhost_dev *d, int ioctl, void __user *argp); int vhost_vq_access_ok(struct vhost_virtqueue *vq); int vhost_log_access_ok(struct vhost_dev *); -int vhost_get_vq_desc(struct vhost_dev *, struct vhost_virtqueue *, +int vhost_get_vq_desc(struct vhost_virtqueue *, struct iovec iov[], unsigned int iov_count, unsigned int *out_num, unsigned int *in_num, struct vhost_log *log, unsigned int *log_num); @@ -201,21 +170,10 @@ enum { (1ULL << VIRTIO_RING_F_INDIRECT_DESC) | (1ULL << VIRTIO_RING_F_EVENT_IDX) | (1ULL << VHOST_F_LOG_ALL), - VHOST_NET_FEATURES = VHOST_FEATURES | - (1ULL << VHOST_NET_F_VIRTIO_NET_HDR) | - (1ULL << VIRTIO_NET_F_MRG_RXBUF), }; -static inline int vhost_has_feature(struct vhost_dev *dev, int bit) +static inline int vhost_has_feature(struct vhost_virtqueue *vq, int bit) { - unsigned acked_features; - - /* TODO: check that we are running from vhost_worker or dev mutex is - * held? */ - acked_features = rcu_dereference_index_check(dev->acked_features, 1); - return acked_features & (1 << bit); + return vq->acked_features & (1 << bit); } - -void vhost_enable_zcopy(int vq); - #endif diff --git a/drivers/vhost/vringh.c b/drivers/vhost/vringh.c new file mode 100644 index 00000000000..5174ebac288 --- /dev/null +++ b/drivers/vhost/vringh.c @@ -0,0 +1,1010 @@ +/* + * Helpers for the host side of a virtio ring. + * + * Since these may be in userspace, we use (inline) accessors. + */ +#include <linux/module.h> +#include <linux/vringh.h> +#include <linux/virtio_ring.h> +#include <linux/kernel.h> +#include <linux/ratelimit.h> +#include <linux/uaccess.h> +#include <linux/slab.h> +#include <linux/export.h> + +static __printf(1,2) __cold void vringh_bad(const char *fmt, ...) +{ + static DEFINE_RATELIMIT_STATE(vringh_rs, + DEFAULT_RATELIMIT_INTERVAL, + DEFAULT_RATELIMIT_BURST); + if (__ratelimit(&vringh_rs)) { + va_list ap; + va_start(ap, fmt); + printk(KERN_NOTICE "vringh:"); + vprintk(fmt, ap); + va_end(ap); + } +} + +/* Returns vring->num if empty, -ve on error. */ +static inline int __vringh_get_head(const struct vringh *vrh, + int (*getu16)(u16 *val, const u16 *p), + u16 *last_avail_idx) +{ + u16 avail_idx, i, head; + int err; + + err = getu16(&avail_idx, &vrh->vring.avail->idx); + if (err) { + vringh_bad("Failed to access avail idx at %p", + &vrh->vring.avail->idx); + return err; + } + + if (*last_avail_idx == avail_idx) + return vrh->vring.num; + + /* Only get avail ring entries after they have been exposed by guest. */ + virtio_rmb(vrh->weak_barriers); + + i = *last_avail_idx & (vrh->vring.num - 1); + + err = getu16(&head, &vrh->vring.avail->ring[i]); + if (err) { + vringh_bad("Failed to read head: idx %d address %p", + *last_avail_idx, &vrh->vring.avail->ring[i]); + return err; + } + + if (head >= vrh->vring.num) { + vringh_bad("Guest says index %u > %u is available", + head, vrh->vring.num); + return -EINVAL; + } + + (*last_avail_idx)++; + return head; +} + +/* Copy some bytes to/from the iovec. Returns num copied. */ +static inline ssize_t vringh_iov_xfer(struct vringh_kiov *iov, + void *ptr, size_t len, + int (*xfer)(void *addr, void *ptr, + size_t len)) +{ + int err, done = 0; + + while (len && iov->i < iov->used) { + size_t partlen; + + partlen = min(iov->iov[iov->i].iov_len, len); + err = xfer(iov->iov[iov->i].iov_base, ptr, partlen); + if (err) + return err; + done += partlen; + len -= partlen; + ptr += partlen; + iov->consumed += partlen; + iov->iov[iov->i].iov_len -= partlen; + iov->iov[iov->i].iov_base += partlen; + + if (!iov->iov[iov->i].iov_len) { + /* Fix up old iov element then increment. */ + iov->iov[iov->i].iov_len = iov->consumed; + iov->iov[iov->i].iov_base -= iov->consumed; + + iov->consumed = 0; + iov->i++; + } + } + return done; +} + +/* May reduce *len if range is shorter. */ +static inline bool range_check(struct vringh *vrh, u64 addr, size_t *len, + struct vringh_range *range, + bool (*getrange)(struct vringh *, + u64, struct vringh_range *)) +{ + if (addr < range->start || addr > range->end_incl) { + if (!getrange(vrh, addr, range)) + return false; + } + BUG_ON(addr < range->start || addr > range->end_incl); + + /* To end of memory? */ + if (unlikely(addr + *len == 0)) { + if (range->end_incl == -1ULL) + return true; + goto truncate; + } + + /* Otherwise, don't wrap. */ + if (addr + *len < addr) { + vringh_bad("Wrapping descriptor %zu@0x%llx", + *len, (unsigned long long)addr); + return false; + } + + if (unlikely(addr + *len - 1 > range->end_incl)) + goto truncate; + return true; + +truncate: + *len = range->end_incl + 1 - addr; + return true; +} + +static inline bool no_range_check(struct vringh *vrh, u64 addr, size_t *len, + struct vringh_range *range, + bool (*getrange)(struct vringh *, + u64, struct vringh_range *)) +{ + return true; +} + +/* No reason for this code to be inline. */ +static int move_to_indirect(int *up_next, u16 *i, void *addr, + const struct vring_desc *desc, + struct vring_desc **descs, int *desc_max) +{ + /* Indirect tables can't have indirect. */ + if (*up_next != -1) { + vringh_bad("Multilevel indirect %u->%u", *up_next, *i); + return -EINVAL; + } + + if (unlikely(desc->len % sizeof(struct vring_desc))) { + vringh_bad("Strange indirect len %u", desc->len); + return -EINVAL; + } + + /* We will check this when we follow it! */ + if (desc->flags & VRING_DESC_F_NEXT) + *up_next = desc->next; + else + *up_next = -2; + *descs = addr; + *desc_max = desc->len / sizeof(struct vring_desc); + + /* Now, start at the first indirect. */ + *i = 0; + return 0; +} + +static int resize_iovec(struct vringh_kiov *iov, gfp_t gfp) +{ + struct kvec *new; + unsigned int flag, new_num = (iov->max_num & ~VRINGH_IOV_ALLOCATED) * 2; + + if (new_num < 8) + new_num = 8; + + flag = (iov->max_num & VRINGH_IOV_ALLOCATED); + if (flag) + new = krealloc(iov->iov, new_num * sizeof(struct iovec), gfp); + else { + new = kmalloc(new_num * sizeof(struct iovec), gfp); + if (new) { + memcpy(new, iov->iov, + iov->max_num * sizeof(struct iovec)); + flag = VRINGH_IOV_ALLOCATED; + } + } + if (!new) + return -ENOMEM; + iov->iov = new; + iov->max_num = (new_num | flag); + return 0; +} + +static u16 __cold return_from_indirect(const struct vringh *vrh, int *up_next, + struct vring_desc **descs, int *desc_max) +{ + u16 i = *up_next; + + *up_next = -1; + *descs = vrh->vring.desc; + *desc_max = vrh->vring.num; + return i; +} + +static int slow_copy(struct vringh *vrh, void *dst, const void *src, + bool (*rcheck)(struct vringh *vrh, u64 addr, size_t *len, + struct vringh_range *range, + bool (*getrange)(struct vringh *vrh, + u64, + struct vringh_range *)), + bool (*getrange)(struct vringh *vrh, + u64 addr, + struct vringh_range *r), + struct vringh_range *range, + int (*copy)(void *dst, const void *src, size_t len)) +{ + size_t part, len = sizeof(struct vring_desc); + + do { + u64 addr; + int err; + + part = len; + addr = (u64)(unsigned long)src - range->offset; + + if (!rcheck(vrh, addr, &part, range, getrange)) + return -EINVAL; + + err = copy(dst, src, part); + if (err) + return err; + + dst += part; + src += part; + len -= part; + } while (len); + return 0; +} + +static inline int +__vringh_iov(struct vringh *vrh, u16 i, + struct vringh_kiov *riov, + struct vringh_kiov *wiov, + bool (*rcheck)(struct vringh *vrh, u64 addr, size_t *len, + struct vringh_range *range, + bool (*getrange)(struct vringh *, u64, + struct vringh_range *)), + bool (*getrange)(struct vringh *, u64, struct vringh_range *), + gfp_t gfp, + int (*copy)(void *dst, const void *src, size_t len)) +{ + int err, count = 0, up_next, desc_max; + struct vring_desc desc, *descs; + struct vringh_range range = { -1ULL, 0 }, slowrange; + bool slow = false; + + /* We start traversing vring's descriptor table. */ + descs = vrh->vring.desc; + desc_max = vrh->vring.num; + up_next = -1; + + if (riov) + riov->i = riov->used = 0; + else if (wiov) + wiov->i = wiov->used = 0; + else + /* You must want something! */ + BUG(); + + for (;;) { + void *addr; + struct vringh_kiov *iov; + size_t len; + + if (unlikely(slow)) + err = slow_copy(vrh, &desc, &descs[i], rcheck, getrange, + &slowrange, copy); + else + err = copy(&desc, &descs[i], sizeof(desc)); + if (unlikely(err)) + goto fail; + + if (unlikely(desc.flags & VRING_DESC_F_INDIRECT)) { + /* Make sure it's OK, and get offset. */ + len = desc.len; + if (!rcheck(vrh, desc.addr, &len, &range, getrange)) { + err = -EINVAL; + goto fail; + } + + if (unlikely(len != desc.len)) { + slow = true; + /* We need to save this range to use offset */ + slowrange = range; + } + + addr = (void *)(long)(desc.addr + range.offset); + err = move_to_indirect(&up_next, &i, addr, &desc, + &descs, &desc_max); + if (err) + goto fail; + continue; + } + + if (count++ == vrh->vring.num) { + vringh_bad("Descriptor loop in %p", descs); + err = -ELOOP; + goto fail; + } + + if (desc.flags & VRING_DESC_F_WRITE) + iov = wiov; + else { + iov = riov; + if (unlikely(wiov && wiov->i)) { + vringh_bad("Readable desc %p after writable", + &descs[i]); + err = -EINVAL; + goto fail; + } + } + + if (!iov) { + vringh_bad("Unexpected %s desc", + !wiov ? "writable" : "readable"); + err = -EPROTO; + goto fail; + } + + again: + /* Make sure it's OK, and get offset. */ + len = desc.len; + if (!rcheck(vrh, desc.addr, &len, &range, getrange)) { + err = -EINVAL; + goto fail; + } + addr = (void *)(unsigned long)(desc.addr + range.offset); + + if (unlikely(iov->used == (iov->max_num & ~VRINGH_IOV_ALLOCATED))) { + err = resize_iovec(iov, gfp); + if (err) + goto fail; + } + + iov->iov[iov->used].iov_base = addr; + iov->iov[iov->used].iov_len = len; + iov->used++; + + if (unlikely(len != desc.len)) { + desc.len -= len; + desc.addr += len; + goto again; + } + + if (desc.flags & VRING_DESC_F_NEXT) { + i = desc.next; + } else { + /* Just in case we need to finish traversing above. */ + if (unlikely(up_next > 0)) { + i = return_from_indirect(vrh, &up_next, + &descs, &desc_max); + slow = false; + } else + break; + } + + if (i >= desc_max) { + vringh_bad("Chained index %u > %u", i, desc_max); + err = -EINVAL; + goto fail; + } + } + + return 0; + +fail: + return err; +} + +static inline int __vringh_complete(struct vringh *vrh, + const struct vring_used_elem *used, + unsigned int num_used, + int (*putu16)(u16 *p, u16 val), + int (*putused)(struct vring_used_elem *dst, + const struct vring_used_elem + *src, unsigned num)) +{ + struct vring_used *used_ring; + int err; + u16 used_idx, off; + + used_ring = vrh->vring.used; + used_idx = vrh->last_used_idx + vrh->completed; + + off = used_idx % vrh->vring.num; + + /* Compiler knows num_used == 1 sometimes, hence extra check */ + if (num_used > 1 && unlikely(off + num_used >= vrh->vring.num)) { + u16 part = vrh->vring.num - off; + err = putused(&used_ring->ring[off], used, part); + if (!err) + err = putused(&used_ring->ring[0], used + part, + num_used - part); + } else + err = putused(&used_ring->ring[off], used, num_used); + + if (err) { + vringh_bad("Failed to write %u used entries %u at %p", + num_used, off, &used_ring->ring[off]); + return err; + } + + /* Make sure buffer is written before we update index. */ + virtio_wmb(vrh->weak_barriers); + + err = putu16(&vrh->vring.used->idx, used_idx + num_used); + if (err) { + vringh_bad("Failed to update used index at %p", + &vrh->vring.used->idx); + return err; + } + + vrh->completed += num_used; + return 0; +} + + +static inline int __vringh_need_notify(struct vringh *vrh, + int (*getu16)(u16 *val, const u16 *p)) +{ + bool notify; + u16 used_event; + int err; + + /* Flush out used index update. This is paired with the + * barrier that the Guest executes when enabling + * interrupts. */ + virtio_mb(vrh->weak_barriers); + + /* Old-style, without event indices. */ + if (!vrh->event_indices) { + u16 flags; + err = getu16(&flags, &vrh->vring.avail->flags); + if (err) { + vringh_bad("Failed to get flags at %p", + &vrh->vring.avail->flags); + return err; + } + return (!(flags & VRING_AVAIL_F_NO_INTERRUPT)); + } + + /* Modern: we know when other side wants to know. */ + err = getu16(&used_event, &vring_used_event(&vrh->vring)); + if (err) { + vringh_bad("Failed to get used event idx at %p", + &vring_used_event(&vrh->vring)); + return err; + } + + /* Just in case we added so many that we wrap. */ + if (unlikely(vrh->completed > 0xffff)) + notify = true; + else + notify = vring_need_event(used_event, + vrh->last_used_idx + vrh->completed, + vrh->last_used_idx); + + vrh->last_used_idx += vrh->completed; + vrh->completed = 0; + return notify; +} + +static inline bool __vringh_notify_enable(struct vringh *vrh, + int (*getu16)(u16 *val, const u16 *p), + int (*putu16)(u16 *p, u16 val)) +{ + u16 avail; + + if (!vrh->event_indices) { + /* Old-school; update flags. */ + if (putu16(&vrh->vring.used->flags, 0) != 0) { + vringh_bad("Clearing used flags %p", + &vrh->vring.used->flags); + return true; + } + } else { + if (putu16(&vring_avail_event(&vrh->vring), + vrh->last_avail_idx) != 0) { + vringh_bad("Updating avail event index %p", + &vring_avail_event(&vrh->vring)); + return true; + } + } + + /* They could have slipped one in as we were doing that: make + * sure it's written, then check again. */ + virtio_mb(vrh->weak_barriers); + + if (getu16(&avail, &vrh->vring.avail->idx) != 0) { + vringh_bad("Failed to check avail idx at %p", + &vrh->vring.avail->idx); + return true; + } + + /* This is unlikely, so we just leave notifications enabled + * (if we're using event_indices, we'll only get one + * notification anyway). */ + return avail == vrh->last_avail_idx; +} + +static inline void __vringh_notify_disable(struct vringh *vrh, + int (*putu16)(u16 *p, u16 val)) +{ + if (!vrh->event_indices) { + /* Old-school; update flags. */ + if (putu16(&vrh->vring.used->flags, VRING_USED_F_NO_NOTIFY)) { + vringh_bad("Setting used flags %p", + &vrh->vring.used->flags); + } + } +} + +/* Userspace access helpers: in this case, addresses are really userspace. */ +static inline int getu16_user(u16 *val, const u16 *p) +{ + return get_user(*val, (__force u16 __user *)p); +} + +static inline int putu16_user(u16 *p, u16 val) +{ + return put_user(val, (__force u16 __user *)p); +} + +static inline int copydesc_user(void *dst, const void *src, size_t len) +{ + return copy_from_user(dst, (__force void __user *)src, len) ? + -EFAULT : 0; +} + +static inline int putused_user(struct vring_used_elem *dst, + const struct vring_used_elem *src, + unsigned int num) +{ + return copy_to_user((__force void __user *)dst, src, + sizeof(*dst) * num) ? -EFAULT : 0; +} + +static inline int xfer_from_user(void *src, void *dst, size_t len) +{ + return copy_from_user(dst, (__force void __user *)src, len) ? + -EFAULT : 0; +} + +static inline int xfer_to_user(void *dst, void *src, size_t len) +{ + return copy_to_user((__force void __user *)dst, src, len) ? + -EFAULT : 0; +} + +/** + * vringh_init_user - initialize a vringh for a userspace vring. + * @vrh: the vringh to initialize. + * @features: the feature bits for this ring. + * @num: the number of elements. + * @weak_barriers: true if we only need memory barriers, not I/O. + * @desc: the userpace descriptor pointer. + * @avail: the userpace avail pointer. + * @used: the userpace used pointer. + * + * Returns an error if num is invalid: you should check pointers + * yourself! + */ +int vringh_init_user(struct vringh *vrh, u32 features, + unsigned int num, bool weak_barriers, + struct vring_desc __user *desc, + struct vring_avail __user *avail, + struct vring_used __user *used) +{ + /* Sane power of 2 please! */ + if (!num || num > 0xffff || (num & (num - 1))) { + vringh_bad("Bad ring size %u", num); + return -EINVAL; + } + + vrh->event_indices = (features & (1 << VIRTIO_RING_F_EVENT_IDX)); + vrh->weak_barriers = weak_barriers; + vrh->completed = 0; + vrh->last_avail_idx = 0; + vrh->last_used_idx = 0; + vrh->vring.num = num; + /* vring expects kernel addresses, but only used via accessors. */ + vrh->vring.desc = (__force struct vring_desc *)desc; + vrh->vring.avail = (__force struct vring_avail *)avail; + vrh->vring.used = (__force struct vring_used *)used; + return 0; +} +EXPORT_SYMBOL(vringh_init_user); + +/** + * vringh_getdesc_user - get next available descriptor from userspace ring. + * @vrh: the userspace vring. + * @riov: where to put the readable descriptors (or NULL) + * @wiov: where to put the writable descriptors (or NULL) + * @getrange: function to call to check ranges. + * @head: head index we received, for passing to vringh_complete_user(). + * + * Returns 0 if there was no descriptor, 1 if there was, or -errno. + * + * Note that on error return, you can tell the difference between an + * invalid ring and a single invalid descriptor: in the former case, + * *head will be vrh->vring.num. You may be able to ignore an invalid + * descriptor, but there's not much you can do with an invalid ring. + * + * Note that you may need to clean up riov and wiov, even on error! + */ +int vringh_getdesc_user(struct vringh *vrh, + struct vringh_iov *riov, + struct vringh_iov *wiov, + bool (*getrange)(struct vringh *vrh, + u64 addr, struct vringh_range *r), + u16 *head) +{ + int err; + + *head = vrh->vring.num; + err = __vringh_get_head(vrh, getu16_user, &vrh->last_avail_idx); + if (err < 0) + return err; + + /* Empty... */ + if (err == vrh->vring.num) + return 0; + + /* We need the layouts to be the identical for this to work */ + BUILD_BUG_ON(sizeof(struct vringh_kiov) != sizeof(struct vringh_iov)); + BUILD_BUG_ON(offsetof(struct vringh_kiov, iov) != + offsetof(struct vringh_iov, iov)); + BUILD_BUG_ON(offsetof(struct vringh_kiov, i) != + offsetof(struct vringh_iov, i)); + BUILD_BUG_ON(offsetof(struct vringh_kiov, used) != + offsetof(struct vringh_iov, used)); + BUILD_BUG_ON(offsetof(struct vringh_kiov, max_num) != + offsetof(struct vringh_iov, max_num)); + BUILD_BUG_ON(sizeof(struct iovec) != sizeof(struct kvec)); + BUILD_BUG_ON(offsetof(struct iovec, iov_base) != + offsetof(struct kvec, iov_base)); + BUILD_BUG_ON(offsetof(struct iovec, iov_len) != + offsetof(struct kvec, iov_len)); + BUILD_BUG_ON(sizeof(((struct iovec *)NULL)->iov_base) + != sizeof(((struct kvec *)NULL)->iov_base)); + BUILD_BUG_ON(sizeof(((struct iovec *)NULL)->iov_len) + != sizeof(((struct kvec *)NULL)->iov_len)); + + *head = err; + err = __vringh_iov(vrh, *head, (struct vringh_kiov *)riov, + (struct vringh_kiov *)wiov, + range_check, getrange, GFP_KERNEL, copydesc_user); + if (err) + return err; + + return 1; +} +EXPORT_SYMBOL(vringh_getdesc_user); + +/** + * vringh_iov_pull_user - copy bytes from vring_iov. + * @riov: the riov as passed to vringh_getdesc_user() (updated as we consume) + * @dst: the place to copy. + * @len: the maximum length to copy. + * + * Returns the bytes copied <= len or a negative errno. + */ +ssize_t vringh_iov_pull_user(struct vringh_iov *riov, void *dst, size_t len) +{ + return vringh_iov_xfer((struct vringh_kiov *)riov, + dst, len, xfer_from_user); +} +EXPORT_SYMBOL(vringh_iov_pull_user); + +/** + * vringh_iov_push_user - copy bytes into vring_iov. + * @wiov: the wiov as passed to vringh_getdesc_user() (updated as we consume) + * @dst: the place to copy. + * @len: the maximum length to copy. + * + * Returns the bytes copied <= len or a negative errno. + */ +ssize_t vringh_iov_push_user(struct vringh_iov *wiov, + const void *src, size_t len) +{ + return vringh_iov_xfer((struct vringh_kiov *)wiov, + (void *)src, len, xfer_to_user); +} +EXPORT_SYMBOL(vringh_iov_push_user); + +/** + * vringh_abandon_user - we've decided not to handle the descriptor(s). + * @vrh: the vring. + * @num: the number of descriptors to put back (ie. num + * vringh_get_user() to undo). + * + * The next vringh_get_user() will return the old descriptor(s) again. + */ +void vringh_abandon_user(struct vringh *vrh, unsigned int num) +{ + /* We only update vring_avail_event(vr) when we want to be notified, + * so we haven't changed that yet. */ + vrh->last_avail_idx -= num; +} +EXPORT_SYMBOL(vringh_abandon_user); + +/** + * vringh_complete_user - we've finished with descriptor, publish it. + * @vrh: the vring. + * @head: the head as filled in by vringh_getdesc_user. + * @len: the length of data we have written. + * + * You should check vringh_need_notify_user() after one or more calls + * to this function. + */ +int vringh_complete_user(struct vringh *vrh, u16 head, u32 len) +{ + struct vring_used_elem used; + + used.id = head; + used.len = len; + return __vringh_complete(vrh, &used, 1, putu16_user, putused_user); +} +EXPORT_SYMBOL(vringh_complete_user); + +/** + * vringh_complete_multi_user - we've finished with many descriptors. + * @vrh: the vring. + * @used: the head, length pairs. + * @num_used: the number of used elements. + * + * You should check vringh_need_notify_user() after one or more calls + * to this function. + */ +int vringh_complete_multi_user(struct vringh *vrh, + const struct vring_used_elem used[], + unsigned num_used) +{ + return __vringh_complete(vrh, used, num_used, + putu16_user, putused_user); +} +EXPORT_SYMBOL(vringh_complete_multi_user); + +/** + * vringh_notify_enable_user - we want to know if something changes. + * @vrh: the vring. + * + * This always enables notifications, but returns false if there are + * now more buffers available in the vring. + */ +bool vringh_notify_enable_user(struct vringh *vrh) +{ + return __vringh_notify_enable(vrh, getu16_user, putu16_user); +} +EXPORT_SYMBOL(vringh_notify_enable_user); + +/** + * vringh_notify_disable_user - don't tell us if something changes. + * @vrh: the vring. + * + * This is our normal running state: we disable and then only enable when + * we're going to sleep. + */ +void vringh_notify_disable_user(struct vringh *vrh) +{ + __vringh_notify_disable(vrh, putu16_user); +} +EXPORT_SYMBOL(vringh_notify_disable_user); + +/** + * vringh_need_notify_user - must we tell the other side about used buffers? + * @vrh: the vring we've called vringh_complete_user() on. + * + * Returns -errno or 0 if we don't need to tell the other side, 1 if we do. + */ +int vringh_need_notify_user(struct vringh *vrh) +{ + return __vringh_need_notify(vrh, getu16_user); +} +EXPORT_SYMBOL(vringh_need_notify_user); + +/* Kernelspace access helpers. */ +static inline int getu16_kern(u16 *val, const u16 *p) +{ + *val = ACCESS_ONCE(*p); + return 0; +} + +static inline int putu16_kern(u16 *p, u16 val) +{ + ACCESS_ONCE(*p) = val; + return 0; +} + +static inline int copydesc_kern(void *dst, const void *src, size_t len) +{ + memcpy(dst, src, len); + return 0; +} + +static inline int putused_kern(struct vring_used_elem *dst, + const struct vring_used_elem *src, + unsigned int num) +{ + memcpy(dst, src, num * sizeof(*dst)); + return 0; +} + +static inline int xfer_kern(void *src, void *dst, size_t len) +{ + memcpy(dst, src, len); + return 0; +} + +/** + * vringh_init_kern - initialize a vringh for a kernelspace vring. + * @vrh: the vringh to initialize. + * @features: the feature bits for this ring. + * @num: the number of elements. + * @weak_barriers: true if we only need memory barriers, not I/O. + * @desc: the userpace descriptor pointer. + * @avail: the userpace avail pointer. + * @used: the userpace used pointer. + * + * Returns an error if num is invalid. + */ +int vringh_init_kern(struct vringh *vrh, u32 features, + unsigned int num, bool weak_barriers, + struct vring_desc *desc, + struct vring_avail *avail, + struct vring_used *used) +{ + /* Sane power of 2 please! */ + if (!num || num > 0xffff || (num & (num - 1))) { + vringh_bad("Bad ring size %u", num); + return -EINVAL; + } + + vrh->event_indices = (features & (1 << VIRTIO_RING_F_EVENT_IDX)); + vrh->weak_barriers = weak_barriers; + vrh->completed = 0; + vrh->last_avail_idx = 0; + vrh->last_used_idx = 0; + vrh->vring.num = num; + vrh->vring.desc = desc; + vrh->vring.avail = avail; + vrh->vring.used = used; + return 0; +} +EXPORT_SYMBOL(vringh_init_kern); + +/** + * vringh_getdesc_kern - get next available descriptor from kernelspace ring. + * @vrh: the kernelspace vring. + * @riov: where to put the readable descriptors (or NULL) + * @wiov: where to put the writable descriptors (or NULL) + * @head: head index we received, for passing to vringh_complete_kern(). + * @gfp: flags for allocating larger riov/wiov. + * + * Returns 0 if there was no descriptor, 1 if there was, or -errno. + * + * Note that on error return, you can tell the difference between an + * invalid ring and a single invalid descriptor: in the former case, + * *head will be vrh->vring.num. You may be able to ignore an invalid + * descriptor, but there's not much you can do with an invalid ring. + * + * Note that you may need to clean up riov and wiov, even on error! + */ +int vringh_getdesc_kern(struct vringh *vrh, + struct vringh_kiov *riov, + struct vringh_kiov *wiov, + u16 *head, + gfp_t gfp) +{ + int err; + + err = __vringh_get_head(vrh, getu16_kern, &vrh->last_avail_idx); + if (err < 0) + return err; + + /* Empty... */ + if (err == vrh->vring.num) + return 0; + + *head = err; + err = __vringh_iov(vrh, *head, riov, wiov, no_range_check, NULL, + gfp, copydesc_kern); + if (err) + return err; + + return 1; +} +EXPORT_SYMBOL(vringh_getdesc_kern); + +/** + * vringh_iov_pull_kern - copy bytes from vring_iov. + * @riov: the riov as passed to vringh_getdesc_kern() (updated as we consume) + * @dst: the place to copy. + * @len: the maximum length to copy. + * + * Returns the bytes copied <= len or a negative errno. + */ +ssize_t vringh_iov_pull_kern(struct vringh_kiov *riov, void *dst, size_t len) +{ + return vringh_iov_xfer(riov, dst, len, xfer_kern); +} +EXPORT_SYMBOL(vringh_iov_pull_kern); + +/** + * vringh_iov_push_kern - copy bytes into vring_iov. + * @wiov: the wiov as passed to vringh_getdesc_kern() (updated as we consume) + * @dst: the place to copy. + * @len: the maximum length to copy. + * + * Returns the bytes copied <= len or a negative errno. + */ +ssize_t vringh_iov_push_kern(struct vringh_kiov *wiov, + const void *src, size_t len) +{ + return vringh_iov_xfer(wiov, (void *)src, len, xfer_kern); +} +EXPORT_SYMBOL(vringh_iov_push_kern); + +/** + * vringh_abandon_kern - we've decided not to handle the descriptor(s). + * @vrh: the vring. + * @num: the number of descriptors to put back (ie. num + * vringh_get_kern() to undo). + * + * The next vringh_get_kern() will return the old descriptor(s) again. + */ +void vringh_abandon_kern(struct vringh *vrh, unsigned int num) +{ + /* We only update vring_avail_event(vr) when we want to be notified, + * so we haven't changed that yet. */ + vrh->last_avail_idx -= num; +} +EXPORT_SYMBOL(vringh_abandon_kern); + +/** + * vringh_complete_kern - we've finished with descriptor, publish it. + * @vrh: the vring. + * @head: the head as filled in by vringh_getdesc_kern. + * @len: the length of data we have written. + * + * You should check vringh_need_notify_kern() after one or more calls + * to this function. + */ +int vringh_complete_kern(struct vringh *vrh, u16 head, u32 len) +{ + struct vring_used_elem used; + + used.id = head; + used.len = len; + + return __vringh_complete(vrh, &used, 1, putu16_kern, putused_kern); +} +EXPORT_SYMBOL(vringh_complete_kern); + +/** + * vringh_notify_enable_kern - we want to know if something changes. + * @vrh: the vring. + * + * This always enables notifications, but returns false if there are + * now more buffers available in the vring. + */ +bool vringh_notify_enable_kern(struct vringh *vrh) +{ + return __vringh_notify_enable(vrh, getu16_kern, putu16_kern); +} +EXPORT_SYMBOL(vringh_notify_enable_kern); + +/** + * vringh_notify_disable_kern - don't tell us if something changes. + * @vrh: the vring. + * + * This is our normal running state: we disable and then only enable when + * we're going to sleep. + */ +void vringh_notify_disable_kern(struct vringh *vrh) +{ + __vringh_notify_disable(vrh, putu16_kern); +} +EXPORT_SYMBOL(vringh_notify_disable_kern); + +/** + * vringh_need_notify_kern - must we tell the other side about used buffers? + * @vrh: the vring we've called vringh_complete_kern() on. + * + * Returns -errno or 0 if we don't need to tell the other side, 1 if we do. + */ +int vringh_need_notify_kern(struct vringh *vrh) +{ + return __vringh_need_notify(vrh, getu16_kern); +} +EXPORT_SYMBOL(vringh_need_notify_kern); + +MODULE_LICENSE("GPL"); |