From 7235acdb1144460d9f520f0d931f3cbb79eb244c Mon Sep 17 00:00:00 2001 From: Jason Wang Date: Mon, 25 Apr 2016 22:14:32 -0400 Subject: vhost: simplify work flushing We used to implement the work flushing through tracking queued seq, done seq, and the number of flushing. This patch simplify this by just implement work flushing through another kind of vhost work with completion. This will be used by lockless enqueuing patch. Signed-off-by: Jason Wang Reviewed-by: Michael S. Tsirkin Signed-off-by: Michael S. Tsirkin --- drivers/vhost/vhost.c | 53 ++++++++++++++++++++------------------------------- 1 file changed, 21 insertions(+), 32 deletions(-) (limited to 'drivers') diff --git a/drivers/vhost/vhost.c b/drivers/vhost/vhost.c index 669fef1e2bb6..73dd16d0f587 100644 --- a/drivers/vhost/vhost.c +++ b/drivers/vhost/vhost.c @@ -131,6 +131,19 @@ static void vhost_reset_is_le(struct vhost_virtqueue *vq) vq->is_le = virtio_legacy_is_little_endian(); } +struct vhost_flush_struct { + struct vhost_work work; + struct completion wait_event; +}; + +static void vhost_flush_work(struct vhost_work *work) +{ + struct vhost_flush_struct *s; + + s = container_of(work, struct vhost_flush_struct, work); + complete(&s->wait_event); +} + static void vhost_poll_func(struct file *file, wait_queue_head_t *wqh, poll_table *pt) { @@ -158,8 +171,6 @@ void vhost_work_init(struct vhost_work *work, vhost_work_fn_t fn) INIT_LIST_HEAD(&work->node); work->fn = fn; init_waitqueue_head(&work->done); - work->flushing = 0; - work->queue_seq = work->done_seq = 0; } EXPORT_SYMBOL_GPL(vhost_work_init); @@ -211,31 +222,17 @@ void vhost_poll_stop(struct vhost_poll *poll) } EXPORT_SYMBOL_GPL(vhost_poll_stop); -static bool vhost_work_seq_done(struct vhost_dev *dev, struct vhost_work *work, - unsigned seq) -{ - int left; - - spin_lock_irq(&dev->work_lock); - left = seq - work->done_seq; - spin_unlock_irq(&dev->work_lock); - return left <= 0; -} - void vhost_work_flush(struct vhost_dev *dev, struct vhost_work *work) { - unsigned seq; - int flushing; + struct vhost_flush_struct flush; + + if (dev->worker) { + init_completion(&flush.wait_event); + vhost_work_init(&flush.work, vhost_flush_work); - spin_lock_irq(&dev->work_lock); - seq = work->queue_seq; - work->flushing++; - spin_unlock_irq(&dev->work_lock); - wait_event(work->done, vhost_work_seq_done(dev, work, seq)); - spin_lock_irq(&dev->work_lock); - flushing = --work->flushing; - spin_unlock_irq(&dev->work_lock); - BUG_ON(flushing < 0); + vhost_work_queue(dev, &flush.work); + wait_for_completion(&flush.wait_event); + } } EXPORT_SYMBOL_GPL(vhost_work_flush); @@ -254,7 +251,6 @@ void vhost_work_queue(struct vhost_dev *dev, struct vhost_work *work) spin_lock_irqsave(&dev->work_lock, flags); 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 { @@ -310,7 +306,6 @@ static int vhost_worker(void *data) { struct vhost_dev *dev = data; struct vhost_work *work = NULL; - unsigned uninitialized_var(seq); mm_segment_t oldfs = get_fs(); set_fs(USER_DS); @@ -321,11 +316,6 @@ static int vhost_worker(void *data) set_current_state(TASK_INTERRUPTIBLE); spin_lock_irq(&dev->work_lock); - if (work) { - work->done_seq = seq; - if (work->flushing) - wake_up_all(&work->done); - } if (kthread_should_stop()) { spin_unlock_irq(&dev->work_lock); @@ -336,7 +326,6 @@ static int vhost_worker(void *data) work = list_first_entry(&dev->work_list, struct vhost_work, node); list_del_init(&work->node); - seq = work->queue_seq; } else work = NULL; spin_unlock_irq(&dev->work_lock); -- cgit v1.2.1 From 04b96e5528ca97199b429810fe963185a67dd40e Mon Sep 17 00:00:00 2001 From: Jason Wang Date: Mon, 25 Apr 2016 22:14:33 -0400 Subject: vhost: lockless enqueuing We use spinlock to synchronize the work list now which may cause unnecessary contentions. So this patch switch to use llist to remove this contention. Pktgen tests shows about 5% improvement: Before: ~1300000 pps After: ~1370000 pps Signed-off-by: Jason Wang Reviewed-by: Michael S. Tsirkin Signed-off-by: Michael S. Tsirkin --- drivers/vhost/vhost.c | 52 +++++++++++++++++++++++++-------------------------- drivers/vhost/vhost.h | 7 ++++--- 2 files changed, 29 insertions(+), 30 deletions(-) (limited to 'drivers') diff --git a/drivers/vhost/vhost.c b/drivers/vhost/vhost.c index 73dd16d0f587..0061a7bd85f6 100644 --- a/drivers/vhost/vhost.c +++ b/drivers/vhost/vhost.c @@ -168,7 +168,7 @@ static int vhost_poll_wakeup(wait_queue_t *wait, unsigned mode, int sync, void vhost_work_init(struct vhost_work *work, vhost_work_fn_t fn) { - INIT_LIST_HEAD(&work->node); + clear_bit(VHOST_WORK_QUEUED, &work->flags); work->fn = fn; init_waitqueue_head(&work->done); } @@ -246,15 +246,16 @@ EXPORT_SYMBOL_GPL(vhost_poll_flush); void vhost_work_queue(struct vhost_dev *dev, struct vhost_work *work) { - unsigned long flags; + if (!dev->worker) + return; - spin_lock_irqsave(&dev->work_lock, flags); - if (list_empty(&work->node)) { - list_add_tail(&work->node, &dev->work_list); - spin_unlock_irqrestore(&dev->work_lock, flags); + if (!test_and_set_bit(VHOST_WORK_QUEUED, &work->flags)) { + /* We can only add the work to the list after we're + * sure it was not in the list. + */ + smp_mb(); + llist_add(&work->node, &dev->work_list); wake_up_process(dev->worker); - } else { - spin_unlock_irqrestore(&dev->work_lock, flags); } } EXPORT_SYMBOL_GPL(vhost_work_queue); @@ -262,7 +263,7 @@ EXPORT_SYMBOL_GPL(vhost_work_queue); /* A lockless hint for busy polling code to exit the loop */ bool vhost_has_work(struct vhost_dev *dev) { - return !list_empty(&dev->work_list); + return !llist_empty(&dev->work_list); } EXPORT_SYMBOL_GPL(vhost_has_work); @@ -305,7 +306,8 @@ static void vhost_vq_reset(struct vhost_dev *dev, static int vhost_worker(void *data) { struct vhost_dev *dev = data; - struct vhost_work *work = NULL; + struct vhost_work *work, *work_next; + struct llist_node *node; mm_segment_t oldfs = get_fs(); set_fs(USER_DS); @@ -315,29 +317,25 @@ static int vhost_worker(void *data) /* mb paired w/ kthread_stop */ set_current_state(TASK_INTERRUPTIBLE); - spin_lock_irq(&dev->work_lock); - if (kthread_should_stop()) { - spin_unlock_irq(&dev->work_lock); __set_current_state(TASK_RUNNING); break; } - if (!list_empty(&dev->work_list)) { - work = list_first_entry(&dev->work_list, - struct vhost_work, node); - list_del_init(&work->node); - } else - work = NULL; - spin_unlock_irq(&dev->work_lock); - if (work) { + node = llist_del_all(&dev->work_list); + if (!node) + schedule(); + + node = llist_reverse_order(node); + /* make sure flag is seen after deletion */ + smp_wmb(); + llist_for_each_entry_safe(work, work_next, node, node) { + clear_bit(VHOST_WORK_QUEUED, &work->flags); __set_current_state(TASK_RUNNING); work->fn(work); if (need_resched()) schedule(); - } else - schedule(); - + } } unuse_mm(dev->mm); set_fs(oldfs); @@ -398,9 +396,9 @@ void vhost_dev_init(struct vhost_dev *dev, dev->log_file = NULL; dev->memory = NULL; dev->mm = NULL; - spin_lock_init(&dev->work_lock); - INIT_LIST_HEAD(&dev->work_list); dev->worker = NULL; + init_llist_head(&dev->work_list); + for (i = 0; i < dev->nvqs; ++i) { vq = dev->vqs[i]; @@ -566,7 +564,7 @@ void vhost_dev_cleanup(struct vhost_dev *dev, bool locked) /* No one will access memory at this point */ kvfree(dev->memory); dev->memory = NULL; - WARN_ON(!list_empty(&dev->work_list)); + WARN_ON(!llist_empty(&dev->work_list)); if (dev->worker) { kthread_stop(dev->worker); dev->worker = NULL; diff --git a/drivers/vhost/vhost.h b/drivers/vhost/vhost.h index d36d8beb3351..6690e645d2f8 100644 --- a/drivers/vhost/vhost.h +++ b/drivers/vhost/vhost.h @@ -15,13 +15,15 @@ struct vhost_work; typedef void (*vhost_work_fn_t)(struct vhost_work *work); +#define VHOST_WORK_QUEUED 1 struct vhost_work { - struct list_head node; + struct llist_node node; vhost_work_fn_t fn; wait_queue_head_t done; int flushing; unsigned queue_seq; unsigned done_seq; + unsigned long flags; }; /* Poll a file (eventfd or socket) */ @@ -126,8 +128,7 @@ struct vhost_dev { int nvqs; struct file *log_file; struct eventfd_ctx *log_ctx; - spinlock_t work_lock; - struct list_head work_list; + struct llist_head work_list; struct task_struct *worker; }; -- cgit v1.2.1 From 37cf99e08c6fb4dcea0f9ad2b13b6daa8c76a711 Mon Sep 17 00:00:00 2001 From: Konstantin Neumoin Date: Mon, 11 Jul 2016 15:28:59 +0300 Subject: balloon: check the number of available pages in leak balloon The balloon has a special mechanism that is subscribed to the oom notification which leads to deflation for a fixed number of pages. The number is always fixed even when the balloon is fully deflated. But leak_balloon did not expect that the pages to deflate will be more than taken, and raise a "BUG" in balloon_page_dequeue when page list will be empty. So, the simplest solution would be to check that the number of releases pages is less or equal to the number taken pages. Cc: stable@vger.kernel.org Signed-off-by: Konstantin Neumoin Signed-off-by: Denis V. Lunev CC: Michael S. Tsirkin Signed-off-by: Michael S. Tsirkin --- drivers/virtio/virtio_balloon.c | 2 ++ 1 file changed, 2 insertions(+) (limited to 'drivers') diff --git a/drivers/virtio/virtio_balloon.c b/drivers/virtio/virtio_balloon.c index 476c0e3a7150..f6ea8f4ba7cf 100644 --- a/drivers/virtio/virtio_balloon.c +++ b/drivers/virtio/virtio_balloon.c @@ -202,6 +202,8 @@ static unsigned leak_balloon(struct virtio_balloon *vb, size_t num) num = min(num, ARRAY_SIZE(vb->pfns)); mutex_lock(&vb->balloon_lock); + /* We can't release more pages than taken */ + num = min(num, (size_t)vb->num_pages); for (vb->num_pfns = 0; vb->num_pfns < num; vb->num_pfns += VIRTIO_BALLOON_PAGES_PER_PAGE) { page = balloon_page_dequeue(vb_dev_info); -- cgit v1.2.1 From 1a937693993ff10d7e80cca6ddd55f3000aa6376 Mon Sep 17 00:00:00 2001 From: "Michael S. Tsirkin" Date: Mon, 18 Apr 2016 12:58:14 +0300 Subject: virtio: new feature to detect IOMMU device quirk The interaction between virtio and IOMMUs is messy. On most systems with virtio, physical addresses match bus addresses, and it doesn't particularly matter which one we use to program the device. On some systems, including Xen and any system with a physical device that speaks virtio behind a physical IOMMU, we must program the IOMMU for virtio DMA to work at all. On other systems, including SPARC and PPC64, virtio-pci devices are enumerated as though they are behind an IOMMU, but the virtio host ignores the IOMMU, so we must either pretend that the IOMMU isn't there or somehow map everything as the identity. Add a feature bit to detect that quirk: VIRTIO_F_IOMMU_PLATFORM. Any device with this feature bit set to 0 needs a quirk and has to be passed physical addresses (as opposed to bus addresses) even though the device is behind an IOMMU. Note: it has to be a per-device quirk because for example, there could be a mix of passed-through and virtual virtio devices. As another example, some devices could be implemented by an out of process hypervisor backend (in case of qemu vhost, or vhost-user) and so support for an IOMMU needs to be coded up separately. It would be cleanest to handle this in IOMMU core code, but that needs per-device DMA ops. While we are waiting for that to be implemented, use a work-around in virtio core. Note: a "noiommu" feature is a quirk - add a wrapper to make that clear. Signed-off-by: Michael S. Tsirkin --- drivers/virtio/virtio_ring.c | 15 ++++++++++++++- 1 file changed, 14 insertions(+), 1 deletion(-) (limited to 'drivers') diff --git a/drivers/virtio/virtio_ring.c b/drivers/virtio/virtio_ring.c index ca6bfddaacad..114a0c88afb8 100644 --- a/drivers/virtio/virtio_ring.c +++ b/drivers/virtio/virtio_ring.c @@ -117,7 +117,10 @@ struct vring_virtqueue { #define to_vvq(_vq) container_of(_vq, struct vring_virtqueue, vq) /* - * The interaction between virtio and a possible IOMMU is a mess. + * Modern virtio devices have feature bits to specify whether they need a + * quirk and bypass the IOMMU. If not there, just use the DMA API. + * + * If there, the interaction between virtio and DMA API is messy. * * On most systems with virtio, physical addresses match bus addresses, * and it doesn't particularly matter whether we use the DMA API. @@ -133,10 +136,18 @@ struct vring_virtqueue { * * For the time being, we preserve historic behavior and bypass the DMA * API. + * + * TODO: install a per-device DMA ops structure that does the right thing + * taking into account all the above quirks, and use the DMA API + * unconditionally on data path. */ static bool vring_use_dma_api(struct virtio_device *vdev) { + if (!virtio_has_iommu_quirk(vdev)) + return true; + + /* Otherwise, we are left to guess. */ /* * In theory, it's possible to have a buggy QEMU-supposed * emulated Q35 IOMMU and Xen enabled at the same time. On @@ -1099,6 +1110,8 @@ void vring_transport_features(struct virtio_device *vdev) break; case VIRTIO_F_VERSION_1: break; + case VIRTIO_F_IOMMU_PLATFORM: + break; default: /* We don't understand this bit. */ __virtio_clear_bit(vdev, i); -- cgit v1.2.1 From 48783646bdd9311fb754895854433be9bb189b0a Mon Sep 17 00:00:00 2001 From: "Michael S. Tsirkin" Date: Tue, 2 Aug 2016 02:56:01 +0300 Subject: vop: pull in vhost Kconfig VOP selects VHOST_RING. Pull in Kconfig that includes it to make it self-containing. Signed-off-by: Michael S. Tsirkin --- drivers/misc/mic/Kconfig | 4 ++++ 1 file changed, 4 insertions(+) (limited to 'drivers') diff --git a/drivers/misc/mic/Kconfig b/drivers/misc/mic/Kconfig index 89e5917e1c33..355bcddb3ed4 100644 --- a/drivers/misc/mic/Kconfig +++ b/drivers/misc/mic/Kconfig @@ -146,3 +146,7 @@ config VOP More information about the Intel MIC family as well as the Linux OS and tools for MIC to use with this driver are available from . + +if VOP +source "drivers/vhost/Kconfig" +endif -- cgit v1.2.1 From 6190efb08c16dcd68c64b096a28f47ab33f017d7 Mon Sep 17 00:00:00 2001 From: "Michael S. Tsirkin" Date: Tue, 2 Aug 2016 01:53:13 +0300 Subject: vhost: drop vringh dependency vringh isn't used by vhost net or scsi - it's used by CAIF only at the moment. Drop the dependency. Signed-off-by: Michael S. Tsirkin --- drivers/vhost/Kconfig | 2 -- 1 file changed, 2 deletions(-) (limited to 'drivers') diff --git a/drivers/vhost/Kconfig b/drivers/vhost/Kconfig index 533eaf04f12f..387d30d8f2a8 100644 --- a/drivers/vhost/Kconfig +++ b/drivers/vhost/Kconfig @@ -2,7 +2,6 @@ config VHOST_NET 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 @@ -15,7 +14,6 @@ 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 -- cgit v1.2.1 From 433fc58e6bf2c8bd97e57153ed28e64fd78207b8 Mon Sep 17 00:00:00 2001 From: Asias He Date: Thu, 28 Jul 2016 15:36:34 +0100 Subject: VSOCK: Introduce vhost_vsock.ko VM sockets vhost transport implementation. This driver runs on the host. Signed-off-by: Asias He Signed-off-by: Stefan Hajnoczi Signed-off-by: Michael S. Tsirkin --- drivers/vhost/vsock.c | 722 ++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 722 insertions(+) create mode 100644 drivers/vhost/vsock.c (limited to 'drivers') diff --git a/drivers/vhost/vsock.c b/drivers/vhost/vsock.c new file mode 100644 index 000000000000..028ca16c2d36 --- /dev/null +++ b/drivers/vhost/vsock.c @@ -0,0 +1,722 @@ +/* + * vhost transport for vsock + * + * Copyright (C) 2013-2015 Red Hat, Inc. + * Author: Asias He + * Stefan Hajnoczi + * + * This work is licensed under the terms of the GNU GPL, version 2. + */ +#include +#include +#include +#include +#include +#include +#include +#include + +#include +#include "vhost.h" + +#define VHOST_VSOCK_DEFAULT_HOST_CID 2 + +enum { + VHOST_VSOCK_FEATURES = VHOST_FEATURES, +}; + +/* Used to track all the vhost_vsock instances on the system. */ +static DEFINE_SPINLOCK(vhost_vsock_lock); +static LIST_HEAD(vhost_vsock_list); + +struct vhost_vsock { + struct vhost_dev dev; + struct vhost_virtqueue vqs[2]; + + /* Link to global vhost_vsock_list, protected by vhost_vsock_lock */ + struct list_head list; + + struct vhost_work send_pkt_work; + spinlock_t send_pkt_list_lock; + struct list_head send_pkt_list; /* host->guest pending packets */ + + atomic_t queued_replies; + + u32 guest_cid; +}; + +static u32 vhost_transport_get_local_cid(void) +{ + return VHOST_VSOCK_DEFAULT_HOST_CID; +} + +static struct vhost_vsock *vhost_vsock_get(u32 guest_cid) +{ + struct vhost_vsock *vsock; + + spin_lock_bh(&vhost_vsock_lock); + list_for_each_entry(vsock, &vhost_vsock_list, list) { + u32 other_cid = vsock->guest_cid; + + /* Skip instances that have no CID yet */ + if (other_cid == 0) + continue; + + if (other_cid == guest_cid) { + spin_unlock_bh(&vhost_vsock_lock); + return vsock; + } + } + spin_unlock_bh(&vhost_vsock_lock); + + return NULL; +} + +static void +vhost_transport_do_send_pkt(struct vhost_vsock *vsock, + struct vhost_virtqueue *vq) +{ + struct vhost_virtqueue *tx_vq = &vsock->vqs[VSOCK_VQ_TX]; + bool added = false; + bool restart_tx = false; + + mutex_lock(&vq->mutex); + + if (!vq->private_data) + goto out; + + /* Avoid further vmexits, we're already processing the virtqueue */ + vhost_disable_notify(&vsock->dev, vq); + + for (;;) { + struct virtio_vsock_pkt *pkt; + struct iov_iter iov_iter; + unsigned out, in; + size_t nbytes; + size_t len; + int head; + + spin_lock_bh(&vsock->send_pkt_list_lock); + if (list_empty(&vsock->send_pkt_list)) { + spin_unlock_bh(&vsock->send_pkt_list_lock); + vhost_enable_notify(&vsock->dev, vq); + break; + } + + pkt = list_first_entry(&vsock->send_pkt_list, + struct virtio_vsock_pkt, list); + list_del_init(&pkt->list); + spin_unlock_bh(&vsock->send_pkt_list_lock); + + head = vhost_get_vq_desc(vq, vq->iov, ARRAY_SIZE(vq->iov), + &out, &in, NULL, NULL); + if (head < 0) { + spin_lock_bh(&vsock->send_pkt_list_lock); + list_add(&pkt->list, &vsock->send_pkt_list); + spin_unlock_bh(&vsock->send_pkt_list_lock); + break; + } + + if (head == vq->num) { + spin_lock_bh(&vsock->send_pkt_list_lock); + list_add(&pkt->list, &vsock->send_pkt_list); + spin_unlock_bh(&vsock->send_pkt_list_lock); + + /* We cannot finish yet if more buffers snuck in while + * re-enabling notify. + */ + if (unlikely(vhost_enable_notify(&vsock->dev, vq))) { + vhost_disable_notify(&vsock->dev, vq); + continue; + } + break; + } + + if (out) { + virtio_transport_free_pkt(pkt); + vq_err(vq, "Expected 0 output buffers, got %u\n", out); + break; + } + + len = iov_length(&vq->iov[out], in); + iov_iter_init(&iov_iter, READ, &vq->iov[out], in, len); + + nbytes = copy_to_iter(&pkt->hdr, sizeof(pkt->hdr), &iov_iter); + if (nbytes != sizeof(pkt->hdr)) { + virtio_transport_free_pkt(pkt); + vq_err(vq, "Faulted on copying pkt hdr\n"); + break; + } + + nbytes = copy_to_iter(pkt->buf, pkt->len, &iov_iter); + if (nbytes != pkt->len) { + virtio_transport_free_pkt(pkt); + vq_err(vq, "Faulted on copying pkt buf\n"); + break; + } + + vhost_add_used(vq, head, sizeof(pkt->hdr) + pkt->len); + added = true; + + if (pkt->reply) { + int val; + + val = atomic_dec_return(&vsock->queued_replies); + + /* Do we have resources to resume tx processing? */ + if (val + 1 == tx_vq->num) + restart_tx = true; + } + + virtio_transport_free_pkt(pkt); + } + if (added) + vhost_signal(&vsock->dev, vq); + +out: + mutex_unlock(&vq->mutex); + + if (restart_tx) + vhost_poll_queue(&tx_vq->poll); +} + +static void vhost_transport_send_pkt_work(struct vhost_work *work) +{ + struct vhost_virtqueue *vq; + struct vhost_vsock *vsock; + + vsock = container_of(work, struct vhost_vsock, send_pkt_work); + vq = &vsock->vqs[VSOCK_VQ_RX]; + + vhost_transport_do_send_pkt(vsock, vq); +} + +static int +vhost_transport_send_pkt(struct virtio_vsock_pkt *pkt) +{ + struct vhost_vsock *vsock; + struct vhost_virtqueue *vq; + int len = pkt->len; + + /* Find the vhost_vsock according to guest context id */ + vsock = vhost_vsock_get(le64_to_cpu(pkt->hdr.dst_cid)); + if (!vsock) { + virtio_transport_free_pkt(pkt); + return -ENODEV; + } + + vq = &vsock->vqs[VSOCK_VQ_RX]; + + if (pkt->reply) + atomic_inc(&vsock->queued_replies); + + spin_lock_bh(&vsock->send_pkt_list_lock); + list_add_tail(&pkt->list, &vsock->send_pkt_list); + spin_unlock_bh(&vsock->send_pkt_list_lock); + + vhost_work_queue(&vsock->dev, &vsock->send_pkt_work); + return len; +} + +static struct virtio_vsock_pkt * +vhost_vsock_alloc_pkt(struct vhost_virtqueue *vq, + unsigned int out, unsigned int in) +{ + struct virtio_vsock_pkt *pkt; + struct iov_iter iov_iter; + size_t nbytes; + size_t len; + + if (in != 0) { + vq_err(vq, "Expected 0 input buffers, got %u\n", in); + return NULL; + } + + pkt = kzalloc(sizeof(*pkt), GFP_KERNEL); + if (!pkt) + return NULL; + + len = iov_length(vq->iov, out); + iov_iter_init(&iov_iter, WRITE, vq->iov, out, len); + + nbytes = copy_from_iter(&pkt->hdr, sizeof(pkt->hdr), &iov_iter); + if (nbytes != sizeof(pkt->hdr)) { + vq_err(vq, "Expected %zu bytes for pkt->hdr, got %zu bytes\n", + sizeof(pkt->hdr), nbytes); + kfree(pkt); + return NULL; + } + + if (le16_to_cpu(pkt->hdr.type) == VIRTIO_VSOCK_TYPE_STREAM) + pkt->len = le32_to_cpu(pkt->hdr.len); + + /* No payload */ + if (!pkt->len) + return pkt; + + /* The pkt is too big */ + if (pkt->len > VIRTIO_VSOCK_MAX_PKT_BUF_SIZE) { + kfree(pkt); + return NULL; + } + + pkt->buf = kmalloc(pkt->len, GFP_KERNEL); + if (!pkt->buf) { + kfree(pkt); + return NULL; + } + + nbytes = copy_from_iter(pkt->buf, pkt->len, &iov_iter); + if (nbytes != pkt->len) { + vq_err(vq, "Expected %u byte payload, got %zu bytes\n", + pkt->len, nbytes); + virtio_transport_free_pkt(pkt); + return NULL; + } + + return pkt; +} + +/* Is there space left for replies to rx packets? */ +static bool vhost_vsock_more_replies(struct vhost_vsock *vsock) +{ + struct vhost_virtqueue *vq = &vsock->vqs[VSOCK_VQ_TX]; + int val; + + smp_rmb(); /* paired with atomic_inc() and atomic_dec_return() */ + val = atomic_read(&vsock->queued_replies); + + return val < vq->num; +} + +static void vhost_vsock_handle_tx_kick(struct vhost_work *work) +{ + struct vhost_virtqueue *vq = container_of(work, struct vhost_virtqueue, + poll.work); + struct vhost_vsock *vsock = container_of(vq->dev, struct vhost_vsock, + dev); + struct virtio_vsock_pkt *pkt; + int head; + unsigned int out, in; + bool added = false; + + mutex_lock(&vq->mutex); + + if (!vq->private_data) + goto out; + + vhost_disable_notify(&vsock->dev, vq); + for (;;) { + if (!vhost_vsock_more_replies(vsock)) { + /* Stop tx until the device processes already + * pending replies. Leave tx virtqueue + * callbacks disabled. + */ + goto no_more_replies; + } + + head = vhost_get_vq_desc(vq, vq->iov, ARRAY_SIZE(vq->iov), + &out, &in, NULL, NULL); + if (head < 0) + break; + + if (head == vq->num) { + if (unlikely(vhost_enable_notify(&vsock->dev, vq))) { + vhost_disable_notify(&vsock->dev, vq); + continue; + } + break; + } + + pkt = vhost_vsock_alloc_pkt(vq, out, in); + if (!pkt) { + vq_err(vq, "Faulted on pkt\n"); + continue; + } + + /* Only accept correctly addressed packets */ + if (le64_to_cpu(pkt->hdr.src_cid) == vsock->guest_cid) + virtio_transport_recv_pkt(pkt); + else + virtio_transport_free_pkt(pkt); + + vhost_add_used(vq, head, sizeof(pkt->hdr) + pkt->len); + added = true; + } + +no_more_replies: + if (added) + vhost_signal(&vsock->dev, vq); + +out: + mutex_unlock(&vq->mutex); +} + +static void vhost_vsock_handle_rx_kick(struct vhost_work *work) +{ + struct vhost_virtqueue *vq = container_of(work, struct vhost_virtqueue, + poll.work); + struct vhost_vsock *vsock = container_of(vq->dev, struct vhost_vsock, + dev); + + vhost_transport_do_send_pkt(vsock, vq); +} + +static int vhost_vsock_start(struct vhost_vsock *vsock) +{ + size_t i; + int ret; + + mutex_lock(&vsock->dev.mutex); + + ret = vhost_dev_check_owner(&vsock->dev); + if (ret) + goto err; + + for (i = 0; i < ARRAY_SIZE(vsock->vqs); i++) { + struct vhost_virtqueue *vq = &vsock->vqs[i]; + + mutex_lock(&vq->mutex); + + if (!vhost_vq_access_ok(vq)) { + ret = -EFAULT; + mutex_unlock(&vq->mutex); + goto err_vq; + } + + if (!vq->private_data) { + vq->private_data = vsock; + vhost_vq_init_access(vq); + } + + mutex_unlock(&vq->mutex); + } + + mutex_unlock(&vsock->dev.mutex); + return 0; + +err_vq: + for (i = 0; i < ARRAY_SIZE(vsock->vqs); i++) { + struct vhost_virtqueue *vq = &vsock->vqs[i]; + + mutex_lock(&vq->mutex); + vq->private_data = NULL; + mutex_unlock(&vq->mutex); + } +err: + mutex_unlock(&vsock->dev.mutex); + return ret; +} + +static int vhost_vsock_stop(struct vhost_vsock *vsock) +{ + size_t i; + int ret; + + mutex_lock(&vsock->dev.mutex); + + ret = vhost_dev_check_owner(&vsock->dev); + if (ret) + goto err; + + for (i = 0; i < ARRAY_SIZE(vsock->vqs); i++) { + struct vhost_virtqueue *vq = &vsock->vqs[i]; + + mutex_lock(&vq->mutex); + vq->private_data = NULL; + mutex_unlock(&vq->mutex); + } + +err: + mutex_unlock(&vsock->dev.mutex); + return ret; +} + +static void vhost_vsock_free(struct vhost_vsock *vsock) +{ + if (is_vmalloc_addr(vsock)) + vfree(vsock); + else + kfree(vsock); +} + +static int vhost_vsock_dev_open(struct inode *inode, struct file *file) +{ + struct vhost_virtqueue **vqs; + struct vhost_vsock *vsock; + int ret; + + /* This struct is large and allocation could fail, fall back to vmalloc + * if there is no other way. + */ + vsock = kzalloc(sizeof(*vsock), GFP_KERNEL | __GFP_NOWARN | __GFP_REPEAT); + if (!vsock) { + vsock = vmalloc(sizeof(*vsock)); + if (!vsock) + return -ENOMEM; + } + + vqs = kmalloc_array(ARRAY_SIZE(vsock->vqs), sizeof(*vqs), GFP_KERNEL); + if (!vqs) { + ret = -ENOMEM; + goto out; + } + + atomic_set(&vsock->queued_replies, 0); + + vqs[VSOCK_VQ_TX] = &vsock->vqs[VSOCK_VQ_TX]; + vqs[VSOCK_VQ_RX] = &vsock->vqs[VSOCK_VQ_RX]; + vsock->vqs[VSOCK_VQ_TX].handle_kick = vhost_vsock_handle_tx_kick; + vsock->vqs[VSOCK_VQ_RX].handle_kick = vhost_vsock_handle_rx_kick; + + vhost_dev_init(&vsock->dev, vqs, ARRAY_SIZE(vsock->vqs)); + + file->private_data = vsock; + spin_lock_init(&vsock->send_pkt_list_lock); + INIT_LIST_HEAD(&vsock->send_pkt_list); + vhost_work_init(&vsock->send_pkt_work, vhost_transport_send_pkt_work); + + spin_lock_bh(&vhost_vsock_lock); + list_add_tail(&vsock->list, &vhost_vsock_list); + spin_unlock_bh(&vhost_vsock_lock); + return 0; + +out: + vhost_vsock_free(vsock); + return ret; +} + +static void vhost_vsock_flush(struct vhost_vsock *vsock) +{ + int i; + + for (i = 0; i < ARRAY_SIZE(vsock->vqs); i++) + if (vsock->vqs[i].handle_kick) + vhost_poll_flush(&vsock->vqs[i].poll); + vhost_work_flush(&vsock->dev, &vsock->send_pkt_work); +} + +static void vhost_vsock_reset_orphans(struct sock *sk) +{ + struct vsock_sock *vsk = vsock_sk(sk); + + /* vmci_transport.c doesn't take sk_lock here either. At least we're + * under vsock_table_lock so the sock cannot disappear while we're + * executing. + */ + + if (!vhost_vsock_get(vsk->local_addr.svm_cid)) { + sock_set_flag(sk, SOCK_DONE); + vsk->peer_shutdown = SHUTDOWN_MASK; + sk->sk_state = SS_UNCONNECTED; + sk->sk_err = ECONNRESET; + sk->sk_error_report(sk); + } +} + +static int vhost_vsock_dev_release(struct inode *inode, struct file *file) +{ + struct vhost_vsock *vsock = file->private_data; + + spin_lock_bh(&vhost_vsock_lock); + list_del(&vsock->list); + spin_unlock_bh(&vhost_vsock_lock); + + /* Iterating over all connections for all CIDs to find orphans is + * inefficient. Room for improvement here. */ + vsock_for_each_connected_socket(vhost_vsock_reset_orphans); + + vhost_vsock_stop(vsock); + vhost_vsock_flush(vsock); + vhost_dev_stop(&vsock->dev); + + spin_lock_bh(&vsock->send_pkt_list_lock); + while (!list_empty(&vsock->send_pkt_list)) { + struct virtio_vsock_pkt *pkt; + + pkt = list_first_entry(&vsock->send_pkt_list, + struct virtio_vsock_pkt, list); + list_del_init(&pkt->list); + virtio_transport_free_pkt(pkt); + } + spin_unlock_bh(&vsock->send_pkt_list_lock); + + vhost_dev_cleanup(&vsock->dev, false); + kfree(vsock->dev.vqs); + vhost_vsock_free(vsock); + return 0; +} + +static int vhost_vsock_set_cid(struct vhost_vsock *vsock, u64 guest_cid) +{ + struct vhost_vsock *other; + + /* Refuse reserved CIDs */ + if (guest_cid <= VMADDR_CID_HOST || + guest_cid == U32_MAX) + return -EINVAL; + + /* 64-bit CIDs are not yet supported */ + if (guest_cid > U32_MAX) + return -EINVAL; + + /* Refuse if CID is already in use */ + other = vhost_vsock_get(guest_cid); + if (other && other != vsock) + return -EADDRINUSE; + + spin_lock_bh(&vhost_vsock_lock); + vsock->guest_cid = guest_cid; + spin_unlock_bh(&vhost_vsock_lock); + + return 0; +} + +static int vhost_vsock_set_features(struct vhost_vsock *vsock, u64 features) +{ + struct vhost_virtqueue *vq; + int i; + + if (features & ~VHOST_VSOCK_FEATURES) + return -EOPNOTSUPP; + + mutex_lock(&vsock->dev.mutex); + if ((features & (1 << VHOST_F_LOG_ALL)) && + !vhost_log_access_ok(&vsock->dev)) { + mutex_unlock(&vsock->dev.mutex); + return -EFAULT; + } + + for (i = 0; i < ARRAY_SIZE(vsock->vqs); i++) { + vq = &vsock->vqs[i]; + mutex_lock(&vq->mutex); + vq->acked_features = features; + mutex_unlock(&vq->mutex); + } + mutex_unlock(&vsock->dev.mutex); + return 0; +} + +static long vhost_vsock_dev_ioctl(struct file *f, unsigned int ioctl, + unsigned long arg) +{ + struct vhost_vsock *vsock = f->private_data; + void __user *argp = (void __user *)arg; + u64 guest_cid; + u64 features; + int start; + int r; + + switch (ioctl) { + case VHOST_VSOCK_SET_GUEST_CID: + if (copy_from_user(&guest_cid, argp, sizeof(guest_cid))) + return -EFAULT; + return vhost_vsock_set_cid(vsock, guest_cid); + case VHOST_VSOCK_SET_RUNNING: + if (copy_from_user(&start, argp, sizeof(start))) + return -EFAULT; + if (start) + return vhost_vsock_start(vsock); + else + return vhost_vsock_stop(vsock); + case VHOST_GET_FEATURES: + features = VHOST_VSOCK_FEATURES; + if (copy_to_user(argp, &features, sizeof(features))) + return -EFAULT; + return 0; + case VHOST_SET_FEATURES: + if (copy_from_user(&features, argp, sizeof(features))) + return -EFAULT; + return vhost_vsock_set_features(vsock, features); + default: + mutex_lock(&vsock->dev.mutex); + r = vhost_dev_ioctl(&vsock->dev, ioctl, argp); + if (r == -ENOIOCTLCMD) + r = vhost_vring_ioctl(&vsock->dev, ioctl, argp); + else + vhost_vsock_flush(vsock); + mutex_unlock(&vsock->dev.mutex); + return r; + } +} + +static const struct file_operations vhost_vsock_fops = { + .owner = THIS_MODULE, + .open = vhost_vsock_dev_open, + .release = vhost_vsock_dev_release, + .llseek = noop_llseek, + .unlocked_ioctl = vhost_vsock_dev_ioctl, +}; + +static struct miscdevice vhost_vsock_misc = { + .minor = MISC_DYNAMIC_MINOR, + .name = "vhost-vsock", + .fops = &vhost_vsock_fops, +}; + +static struct virtio_transport vhost_transport = { + .transport = { + .get_local_cid = vhost_transport_get_local_cid, + + .init = virtio_transport_do_socket_init, + .destruct = virtio_transport_destruct, + .release = virtio_transport_release, + .connect = virtio_transport_connect, + .shutdown = virtio_transport_shutdown, + + .dgram_enqueue = virtio_transport_dgram_enqueue, + .dgram_dequeue = virtio_transport_dgram_dequeue, + .dgram_bind = virtio_transport_dgram_bind, + .dgram_allow = virtio_transport_dgram_allow, + + .stream_enqueue = virtio_transport_stream_enqueue, + .stream_dequeue = virtio_transport_stream_dequeue, + .stream_has_data = virtio_transport_stream_has_data, + .stream_has_space = virtio_transport_stream_has_space, + .stream_rcvhiwat = virtio_transport_stream_rcvhiwat, + .stream_is_active = virtio_transport_stream_is_active, + .stream_allow = virtio_transport_stream_allow, + + .notify_poll_in = virtio_transport_notify_poll_in, + .notify_poll_out = virtio_transport_notify_poll_out, + .notify_recv_init = virtio_transport_notify_recv_init, + .notify_recv_pre_block = virtio_transport_notify_recv_pre_block, + .notify_recv_pre_dequeue = virtio_transport_notify_recv_pre_dequeue, + .notify_recv_post_dequeue = virtio_transport_notify_recv_post_dequeue, + .notify_send_init = virtio_transport_notify_send_init, + .notify_send_pre_block = virtio_transport_notify_send_pre_block, + .notify_send_pre_enqueue = virtio_transport_notify_send_pre_enqueue, + .notify_send_post_enqueue = virtio_transport_notify_send_post_enqueue, + + .set_buffer_size = virtio_transport_set_buffer_size, + .set_min_buffer_size = virtio_transport_set_min_buffer_size, + .set_max_buffer_size = virtio_transport_set_max_buffer_size, + .get_buffer_size = virtio_transport_get_buffer_size, + .get_min_buffer_size = virtio_transport_get_min_buffer_size, + .get_max_buffer_size = virtio_transport_get_max_buffer_size, + }, + + .send_pkt = vhost_transport_send_pkt, +}; + +static int __init vhost_vsock_init(void) +{ + int ret; + + ret = vsock_core_init(&vhost_transport.transport); + if (ret < 0) + return ret; + return misc_register(&vhost_vsock_misc); +}; + +static void __exit vhost_vsock_exit(void) +{ + misc_deregister(&vhost_vsock_misc); + vsock_core_exit(); +}; + +module_init(vhost_vsock_init); +module_exit(vhost_vsock_exit); +MODULE_LICENSE("GPL v2"); +MODULE_AUTHOR("Asias He"); +MODULE_DESCRIPTION("vhost transport for vsock "); -- cgit v1.2.1 From 304ba62fd4e670c1a5784585da0fac9f7309ef6c Mon Sep 17 00:00:00 2001 From: Asias He Date: Thu, 28 Jul 2016 15:36:35 +0100 Subject: VSOCK: Add Makefile and Kconfig Enable virtio-vsock and vhost-vsock. Signed-off-by: Asias He Signed-off-by: Stefan Hajnoczi Signed-off-by: Michael S. Tsirkin --- drivers/vhost/Kconfig | 14 ++++++++++++++ drivers/vhost/Makefile | 4 ++++ 2 files changed, 18 insertions(+) (limited to 'drivers') diff --git a/drivers/vhost/Kconfig b/drivers/vhost/Kconfig index 387d30d8f2a8..f77f15bd3b0c 100644 --- a/drivers/vhost/Kconfig +++ b/drivers/vhost/Kconfig @@ -19,6 +19,20 @@ config VHOST_SCSI Say M here to enable the vhost_scsi TCM fabric module for use with virtio-scsi guests +config VHOST_VSOCK + tristate "vhost virtio-vsock driver" + depends on VSOCKETS && EVENTFD + select VIRTIO_VSOCKETS_COMMON + select VHOST + default n + ---help--- + This kernel module can be loaded in the host kernel to provide AF_VSOCK + sockets for communicating with guests. The guests must have the + virtio_transport.ko driver loaded to use the virtio-vsock device. + + To compile this driver as a module, choose M here: the module will be called + vhost_vsock. + config VHOST_RING tristate ---help--- diff --git a/drivers/vhost/Makefile b/drivers/vhost/Makefile index e0441c34db1c..6b012b986b57 100644 --- a/drivers/vhost/Makefile +++ b/drivers/vhost/Makefile @@ -4,5 +4,9 @@ vhost_net-y := net.o obj-$(CONFIG_VHOST_SCSI) += vhost_scsi.o vhost_scsi-y := scsi.o +obj-$(CONFIG_VHOST_VSOCK) += vhost_vsock.o +vhost_vsock-y := vsock.o + obj-$(CONFIG_VHOST_RING) += vringh.o + obj-$(CONFIG_VHOST) += vhost.o -- cgit v1.2.1 From bfe2bc512884d0b1c5297a15350f940ca80e439b Mon Sep 17 00:00:00 2001 From: Jason Wang Date: Thu, 23 Jun 2016 02:04:30 -0400 Subject: vhost: introduce vhost memory accessors This patch introduces vhost memory accessors which were just wrappers for userspace address access helpers. This is a requirement for vhost device iotlb implementation which will add iotlb translations in those accessors. Signed-off-by: Jason Wang Signed-off-by: Michael S. Tsirkin --- drivers/vhost/vhost.c | 50 +++++++++++++++++++++++++++++++++++--------------- 1 file changed, 35 insertions(+), 15 deletions(-) (limited to 'drivers') diff --git a/drivers/vhost/vhost.c b/drivers/vhost/vhost.c index 0061a7bd85f6..e1b5047d8f19 100644 --- a/drivers/vhost/vhost.c +++ b/drivers/vhost/vhost.c @@ -638,6 +638,22 @@ static int memory_access_ok(struct vhost_dev *d, struct vhost_memory *mem, return 1; } +#define vhost_put_user(vq, x, ptr) __put_user(x, ptr) + +static int vhost_copy_to_user(struct vhost_virtqueue *vq, void *to, + const void *from, unsigned size) +{ + return __copy_to_user(to, from, size); +} + +#define vhost_get_user(vq, x, ptr) __get_user(x, ptr) + +static int vhost_copy_from_user(struct vhost_virtqueue *vq, void *to, + void *from, unsigned size) +{ + return __copy_from_user(to, from, size); +} + static int vq_access_ok(struct vhost_virtqueue *vq, unsigned int num, struct vring_desc __user *desc, struct vring_avail __user *avail, @@ -1143,7 +1159,8 @@ EXPORT_SYMBOL_GPL(vhost_log_write); static int vhost_update_used_flags(struct vhost_virtqueue *vq) { void __user *used; - if (__put_user(cpu_to_vhost16(vq, vq->used_flags), &vq->used->flags) < 0) + if (vhost_put_user(vq, cpu_to_vhost16(vq, vq->used_flags), + &vq->used->flags) < 0) return -EFAULT; if (unlikely(vq->log_used)) { /* Make sure the flag is seen before log. */ @@ -1161,7 +1178,8 @@ static int vhost_update_used_flags(struct vhost_virtqueue *vq) static int vhost_update_avail_event(struct vhost_virtqueue *vq, u16 avail_event) { - if (__put_user(cpu_to_vhost16(vq, vq->avail_idx), vhost_avail_event(vq))) + if (vhost_put_user(vq, cpu_to_vhost16(vq, vq->avail_idx), + vhost_avail_event(vq))) return -EFAULT; if (unlikely(vq->log_used)) { void __user *used; @@ -1199,7 +1217,7 @@ int vhost_vq_init_access(struct vhost_virtqueue *vq) r = -EFAULT; goto err; } - r = __get_user(last_used_idx, &vq->used->idx); + r = vhost_get_user(vq, last_used_idx, &vq->used->idx); if (r) goto err; vq->last_used_idx = vhost16_to_cpu(vq, last_used_idx); @@ -1379,7 +1397,7 @@ int vhost_get_vq_desc(struct vhost_virtqueue *vq, /* Check it isn't doing very strange things with descriptor numbers. */ last_avail_idx = vq->last_avail_idx; - if (unlikely(__get_user(avail_idx, &vq->avail->idx))) { + if (unlikely(vhost_get_user(vq, avail_idx, &vq->avail->idx))) { vq_err(vq, "Failed to access avail idx at %p\n", &vq->avail->idx); return -EFAULT; @@ -1401,8 +1419,8 @@ int vhost_get_vq_desc(struct vhost_virtqueue *vq, /* Grab the next descriptor number they're advertising, and increment * the index we've seen. */ - if (unlikely(__get_user(ring_head, - &vq->avail->ring[last_avail_idx & (vq->num - 1)]))) { + if (unlikely(vhost_get_user(vq, ring_head, + &vq->avail->ring[last_avail_idx & (vq->num - 1)]))) { vq_err(vq, "Failed to read head: idx %d address %p\n", last_avail_idx, &vq->avail->ring[last_avail_idx % vq->num]); @@ -1437,7 +1455,8 @@ int vhost_get_vq_desc(struct vhost_virtqueue *vq, i, vq->num, head); return -EINVAL; } - ret = __copy_from_user(&desc, vq->desc + i, sizeof desc); + ret = vhost_copy_from_user(vq, &desc, vq->desc + i, + sizeof desc); if (unlikely(ret)) { vq_err(vq, "Failed to get descriptor: idx %d addr %p\n", i, vq->desc + i); @@ -1525,15 +1544,15 @@ static int __vhost_add_used_n(struct vhost_virtqueue *vq, start = vq->last_used_idx & (vq->num - 1); used = vq->used->ring + start; if (count == 1) { - if (__put_user(heads[0].id, &used->id)) { + if (vhost_put_user(vq, heads[0].id, &used->id)) { vq_err(vq, "Failed to write used id"); return -EFAULT; } - if (__put_user(heads[0].len, &used->len)) { + if (vhost_put_user(vq, 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)) { + } else if (vhost_copy_to_user(vq, used, heads, count * sizeof *used)) { vq_err(vq, "Failed to write used"); return -EFAULT; } @@ -1577,7 +1596,8 @@ int vhost_add_used_n(struct vhost_virtqueue *vq, struct vring_used_elem *heads, /* Make sure buffer is written before we update index. */ smp_wmb(); - if (__put_user(cpu_to_vhost16(vq, vq->last_used_idx), &vq->used->idx)) { + if (vhost_put_user(vq, cpu_to_vhost16(vq, vq->last_used_idx), + &vq->used->idx)) { vq_err(vq, "Failed to increment used idx"); return -EFAULT; } @@ -1609,7 +1629,7 @@ static bool vhost_notify(struct vhost_dev *dev, struct vhost_virtqueue *vq) if (!vhost_has_feature(vq, VIRTIO_RING_F_EVENT_IDX)) { __virtio16 flags; - if (__get_user(flags, &vq->avail->flags)) { + if (vhost_get_user(vq, flags, &vq->avail->flags)) { vq_err(vq, "Failed to get flags"); return true; } @@ -1623,7 +1643,7 @@ static bool vhost_notify(struct vhost_dev *dev, struct vhost_virtqueue *vq) if (unlikely(!v)) return true; - if (__get_user(event, vhost_used_event(vq))) { + if (vhost_get_user(vq, event, vhost_used_event(vq))) { vq_err(vq, "Failed to get used event idx"); return true; } @@ -1665,7 +1685,7 @@ bool vhost_vq_avail_empty(struct vhost_dev *dev, struct vhost_virtqueue *vq) __virtio16 avail_idx; int r; - r = __get_user(avail_idx, &vq->avail->idx); + r = vhost_get_user(vq, avail_idx, &vq->avail->idx); if (r) return false; @@ -1700,7 +1720,7 @@ bool vhost_enable_notify(struct vhost_dev *dev, struct vhost_virtqueue *vq) /* They could have slipped one in as we were doing that: make * sure it's written, then check again. */ smp_mb(); - r = __get_user(avail_idx, &vq->avail->idx); + r = vhost_get_user(vq, avail_idx, &vq->avail->idx); if (r) { vq_err(vq, "Failed to check avail idx at %p: %d\n", &vq->avail->idx, r); -- cgit v1.2.1 From a9709d6874d55130663567577a9b05c35138cc6b Mon Sep 17 00:00:00 2001 From: Jason Wang Date: Thu, 23 Jun 2016 02:04:31 -0400 Subject: vhost: convert pre sorted vhost memory array to interval tree Current pre-sorted memory region array has some limitations for future device IOTLB conversion: 1) need extra work for adding and removing a single region, and it's expected to be slow because of sorting or memory re-allocation. 2) need extra work of removing a large range which may intersect several regions with different size. 3) need trick for a replacement policy like LRU To overcome the above shortcomings, this patch convert it to interval tree which can easily address the above issue with almost no extra work. The patch could be used for: - Extend the current API and only let the userspace to send diffs of memory table. - Simplify Device IOTLB implementation. Signed-off-by: Jason Wang Signed-off-by: Michael S. Tsirkin --- drivers/vhost/net.c | 8 +-- drivers/vhost/vhost.c | 182 ++++++++++++++++++++++++++++---------------------- drivers/vhost/vhost.h | 27 ++++++-- 3 files changed, 128 insertions(+), 89 deletions(-) (limited to 'drivers') diff --git a/drivers/vhost/net.c b/drivers/vhost/net.c index f744eeb3e2b4..a6b270aff9ef 100644 --- a/drivers/vhost/net.c +++ b/drivers/vhost/net.c @@ -1036,20 +1036,20 @@ 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; + struct vhost_umem *umem; mutex_lock(&n->dev.mutex); err = vhost_dev_check_owner(&n->dev); if (err) goto done; - memory = vhost_dev_reset_owner_prepare(); - if (!memory) { + umem = vhost_dev_reset_owner_prepare(); + if (!umem) { err = -ENOMEM; goto done; } vhost_net_stop(n, &tx_sock, &rx_sock); vhost_net_flush(n); - vhost_dev_reset_owner(&n->dev, memory); + vhost_dev_reset_owner(&n->dev, umem); vhost_net_vq_reset(n); done: mutex_unlock(&n->dev.mutex); diff --git a/drivers/vhost/vhost.c b/drivers/vhost/vhost.c index e1b5047d8f19..8071f3638db9 100644 --- a/drivers/vhost/vhost.c +++ b/drivers/vhost/vhost.c @@ -27,6 +27,7 @@ #include #include #include +#include #include "vhost.h" @@ -42,6 +43,10 @@ enum { #define vhost_used_event(vq) ((__virtio16 __user *)&vq->avail->ring[vq->num]) #define vhost_avail_event(vq) ((__virtio16 __user *)&vq->used->ring[vq->num]) +INTERVAL_TREE_DEFINE(struct vhost_umem_node, + rb, __u64, __subtree_last, + START, LAST, , vhost_umem_interval_tree); + #ifdef CONFIG_VHOST_CROSS_ENDIAN_LEGACY static void vhost_disable_cross_endian(struct vhost_virtqueue *vq) { @@ -297,10 +302,10 @@ static void vhost_vq_reset(struct vhost_dev *dev, vq->call_ctx = NULL; vq->call = NULL; vq->log_ctx = NULL; - vq->memory = NULL; vhost_reset_is_le(vq); vhost_disable_cross_endian(vq); vq->busyloop_timeout = 0; + vq->umem = NULL; } static int vhost_worker(void *data) @@ -394,7 +399,7 @@ void vhost_dev_init(struct vhost_dev *dev, mutex_init(&dev->mutex); dev->log_ctx = NULL; dev->log_file = NULL; - dev->memory = NULL; + dev->umem = NULL; dev->mm = NULL; dev->worker = NULL; init_llist_head(&dev->work_list); @@ -499,27 +504,36 @@ err_mm: } EXPORT_SYMBOL_GPL(vhost_dev_set_owner); -struct vhost_memory *vhost_dev_reset_owner_prepare(void) +static void *vhost_kvzalloc(unsigned long size) { - return kmalloc(offsetof(struct vhost_memory, regions), GFP_KERNEL); + void *n = kzalloc(size, GFP_KERNEL | __GFP_NOWARN | __GFP_REPEAT); + + if (!n) + n = vzalloc(size); + return n; +} + +struct vhost_umem *vhost_dev_reset_owner_prepare(void) +{ + return vhost_kvzalloc(sizeof(struct vhost_umem)); } EXPORT_SYMBOL_GPL(vhost_dev_reset_owner_prepare); /* Caller should have device mutex */ -void vhost_dev_reset_owner(struct vhost_dev *dev, struct vhost_memory *memory) +void vhost_dev_reset_owner(struct vhost_dev *dev, struct vhost_umem *umem) { int i; vhost_dev_cleanup(dev, true); /* Restore memory to default empty mapping. */ - memory->nregions = 0; - dev->memory = memory; + INIT_LIST_HEAD(&umem->umem_list); + dev->umem = umem; /* 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; + dev->vqs[i]->umem = umem; } EXPORT_SYMBOL_GPL(vhost_dev_reset_owner); @@ -536,6 +550,21 @@ void vhost_dev_stop(struct vhost_dev *dev) } EXPORT_SYMBOL_GPL(vhost_dev_stop); +static void vhost_umem_clean(struct vhost_umem *umem) +{ + struct vhost_umem_node *node, *tmp; + + if (!umem) + return; + + list_for_each_entry_safe(node, tmp, &umem->umem_list, link) { + vhost_umem_interval_tree_remove(node, &umem->umem_tree); + list_del(&node->link); + kvfree(node); + } + kvfree(umem); +} + /* Caller should have device mutex if and only if locked is set */ void vhost_dev_cleanup(struct vhost_dev *dev, bool locked) { @@ -562,8 +591,8 @@ 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 */ - kvfree(dev->memory); - dev->memory = NULL; + vhost_umem_clean(dev->umem); + dev->umem = NULL; WARN_ON(!llist_empty(&dev->work_list)); if (dev->worker) { kthread_stop(dev->worker); @@ -589,25 +618,25 @@ static int log_access_ok(void __user *log_base, u64 addr, unsigned long sz) } /* Caller should have vq mutex and device mutex. */ -static int vq_memory_access_ok(void __user *log_base, struct vhost_memory *mem, +static int vq_memory_access_ok(void __user *log_base, struct vhost_umem *umem, int log_all) { - int i; + struct vhost_umem_node *node; - if (!mem) + if (!umem) return 0; - for (i = 0; i < mem->nregions; ++i) { - struct vhost_memory_region *m = mem->regions + i; - unsigned long a = m->userspace_addr; - if (m->memory_size > ULONG_MAX) + list_for_each_entry(node, &umem->umem_list, link) { + unsigned long a = node->userspace_addr; + + if (node->size > ULONG_MAX) return 0; else if (!access_ok(VERIFY_WRITE, (void __user *)a, - m->memory_size)) + node->size)) return 0; else if (log_all && !log_access_ok(log_base, - m->guest_phys_addr, - m->memory_size)) + node->start, + node->size)) return 0; } return 1; @@ -615,7 +644,7 @@ static int vq_memory_access_ok(void __user *log_base, struct vhost_memory *mem, /* Can we switch to this memory table? */ /* Caller should have device mutex but not vq mutex */ -static int memory_access_ok(struct vhost_dev *d, struct vhost_memory *mem, +static int memory_access_ok(struct vhost_dev *d, struct vhost_umem *umem, int log_all) { int i; @@ -628,7 +657,8 @@ static int memory_access_ok(struct vhost_dev *d, struct vhost_memory *mem, 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); + ok = vq_memory_access_ok(d->vqs[i]->log_base, + umem, log); else ok = 1; mutex_unlock(&d->vqs[i]->mutex); @@ -671,7 +701,7 @@ static int vq_access_ok(struct vhost_virtqueue *vq, unsigned int num, /* Caller should have device mutex but not vq mutex */ int vhost_log_access_ok(struct vhost_dev *dev) { - return memory_access_ok(dev, dev->memory, 1); + return memory_access_ok(dev, dev->umem, 1); } EXPORT_SYMBOL_GPL(vhost_log_access_ok); @@ -682,7 +712,7 @@ static int vq_log_access_ok(struct vhost_virtqueue *vq, { size_t s = vhost_has_feature(vq, VIRTIO_RING_F_EVENT_IDX) ? 2 : 0; - return vq_memory_access_ok(log_base, vq->memory, + return vq_memory_access_ok(log_base, vq->umem, vhost_has_feature(vq, VHOST_F_LOG_ALL)) && (!vq->log_used || log_access_ok(log_base, vq->log_addr, sizeof *vq->used + @@ -698,28 +728,12 @@ int vhost_vq_access_ok(struct vhost_virtqueue *vq) } EXPORT_SYMBOL_GPL(vhost_vq_access_ok); -static int vhost_memory_reg_sort_cmp(const void *p1, const void *p2) -{ - const struct vhost_memory_region *r1 = p1, *r2 = p2; - if (r1->guest_phys_addr < r2->guest_phys_addr) - return 1; - if (r1->guest_phys_addr > r2->guest_phys_addr) - return -1; - return 0; -} - -static void *vhost_kvzalloc(unsigned long size) -{ - void *n = kzalloc(size, GFP_KERNEL | __GFP_NOWARN | __GFP_REPEAT); - - if (!n) - n = vzalloc(size); - return n; -} - static long vhost_set_memory(struct vhost_dev *d, struct vhost_memory __user *m) { - struct vhost_memory mem, *newmem, *oldmem; + struct vhost_memory mem, *newmem; + struct vhost_memory_region *region; + struct vhost_umem_node *node; + struct vhost_umem *newumem, *oldumem; unsigned long size = offsetof(struct vhost_memory, regions); int i; @@ -739,24 +753,52 @@ static long vhost_set_memory(struct vhost_dev *d, struct vhost_memory __user *m) kvfree(newmem); return -EFAULT; } - sort(newmem->regions, newmem->nregions, sizeof(*newmem->regions), - vhost_memory_reg_sort_cmp, NULL); - if (!memory_access_ok(d, newmem, 0)) { + newumem = vhost_kvzalloc(sizeof(*newumem)); + if (!newumem) { kvfree(newmem); - return -EFAULT; + return -ENOMEM; + } + + newumem->umem_tree = RB_ROOT; + INIT_LIST_HEAD(&newumem->umem_list); + + for (region = newmem->regions; + region < newmem->regions + mem.nregions; + region++) { + node = vhost_kvzalloc(sizeof(*node)); + if (!node) + goto err; + node->start = region->guest_phys_addr; + node->size = region->memory_size; + node->last = node->start + node->size - 1; + node->userspace_addr = region->userspace_addr; + INIT_LIST_HEAD(&node->link); + list_add_tail(&node->link, &newumem->umem_list); + vhost_umem_interval_tree_insert(node, &newumem->umem_tree); } - oldmem = d->memory; - d->memory = newmem; + + if (!memory_access_ok(d, newumem, 0)) + goto err; + + oldumem = d->umem; + d->umem = newumem; /* 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; + d->vqs[i]->umem = newumem; mutex_unlock(&d->vqs[i]->mutex); } - kvfree(oldmem); + + kvfree(newmem); + vhost_umem_clean(oldumem); return 0; + +err: + vhost_umem_clean(newumem); + kvfree(newmem); + return -EFAULT; } long vhost_vring_ioctl(struct vhost_dev *d, int ioctl, void __user *argp) @@ -1059,28 +1101,6 @@ done: } EXPORT_SYMBOL_GPL(vhost_dev_ioctl); -static const struct vhost_memory_region *find_region(struct vhost_memory *mem, - __u64 addr, __u32 len) -{ - const struct vhost_memory_region *reg; - int start = 0, end = mem->nregions; - - while (start < end) { - int slot = start + (end - start) / 2; - reg = mem->regions + slot; - if (addr >= reg->guest_phys_addr) - end = slot; - else - start = slot + 1; - } - - reg = mem->regions + start; - if (addr >= reg->guest_phys_addr && - reg->guest_phys_addr + reg->memory_size > addr) - return reg; - return NULL; -} - /* TODO: This is really inefficient. We need something like get_user() * (instruction directly accesses the data, with an exception table entry * returning -EFAULT). See Documentation/x86/exception-tables.txt. @@ -1231,29 +1251,29 @@ EXPORT_SYMBOL_GPL(vhost_vq_init_access); static int translate_desc(struct vhost_virtqueue *vq, u64 addr, u32 len, struct iovec iov[], int iov_size) { - const struct vhost_memory_region *reg; - struct vhost_memory *mem; + const struct vhost_umem_node *node; + struct vhost_umem *umem = vq->umem; struct iovec *_iov; u64 s = 0; int ret = 0; - mem = vq->memory; while ((u64)len > s) { u64 size; if (unlikely(ret >= iov_size)) { ret = -ENOBUFS; break; } - reg = find_region(mem, addr, len); - if (unlikely(!reg)) { + node = vhost_umem_interval_tree_iter_first(&umem->umem_tree, + addr, addr + len - 1); + if (node == NULL || node->start > addr) { ret = -EFAULT; break; } _iov = iov + ret; - size = reg->memory_size - addr + reg->guest_phys_addr; + size = node->size - addr + node->start; _iov->iov_len = min((u64)len - s, size); _iov->iov_base = (void __user *)(unsigned long) - (reg->userspace_addr + addr - reg->guest_phys_addr); + (node->userspace_addr + addr - node->start); s += size; addr += size; ++ret; diff --git a/drivers/vhost/vhost.h b/drivers/vhost/vhost.h index 6690e645d2f8..eaaf6df72218 100644 --- a/drivers/vhost/vhost.h +++ b/drivers/vhost/vhost.h @@ -55,6 +55,25 @@ struct vhost_log { u64 len; }; +#define START(node) ((node)->start) +#define LAST(node) ((node)->last) + +struct vhost_umem_node { + struct rb_node rb; + struct list_head link; + __u64 start; + __u64 last; + __u64 size; + __u64 userspace_addr; + __u64 flags_padding; + __u64 __subtree_last; +}; + +struct vhost_umem { + struct rb_root umem_tree; + struct list_head umem_list; +}; + /* The virtqueue structure describes a queue attached to a device. */ struct vhost_virtqueue { struct vhost_dev *dev; @@ -103,7 +122,7 @@ struct vhost_virtqueue { struct iovec *indirect; struct vring_used_elem *heads; /* Protected by virtqueue mutex. */ - struct vhost_memory *memory; + struct vhost_umem *umem; void *private_data; u64 acked_features; /* Log write descriptors */ @@ -121,7 +140,6 @@ struct vhost_virtqueue { }; struct vhost_dev { - struct vhost_memory *memory; struct mm_struct *mm; struct mutex mutex; struct vhost_virtqueue **vqs; @@ -130,14 +148,15 @@ struct vhost_dev { struct eventfd_ctx *log_ctx; struct llist_head work_list; struct task_struct *worker; + struct vhost_umem *umem; }; 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 *); -struct vhost_memory *vhost_dev_reset_owner_prepare(void); -void vhost_dev_reset_owner(struct vhost_dev *, struct vhost_memory *); +struct vhost_umem *vhost_dev_reset_owner_prepare(void); +void vhost_dev_reset_owner(struct vhost_dev *, struct vhost_umem *); 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); -- cgit v1.2.1 From b2fbd8b0737803f527bc7671a14bd6736d78b5d7 Mon Sep 17 00:00:00 2001 From: "Michael S. Tsirkin" Date: Tue, 2 Aug 2016 01:53:13 +0300 Subject: vhost: drop vringh dependency vringh isn't used by vhost net or scsi - it's used by CAIF only at the moment. Drop the dependency. Signed-off-by: Michael S. Tsirkin --- drivers/Makefile | 1 + 1 file changed, 1 insertion(+) (limited to 'drivers') diff --git a/drivers/Makefile b/drivers/Makefile index 0b6f3d60193d..5d03dbad4484 100644 --- a/drivers/Makefile +++ b/drivers/Makefile @@ -139,6 +139,7 @@ obj-$(CONFIG_OF) += of/ obj-$(CONFIG_SSB) += ssb/ obj-$(CONFIG_BCMA) += bcma/ obj-$(CONFIG_VHOST_RING) += vhost/ +obj-$(CONFIG_VHOST) += vhost/ obj-$(CONFIG_VLYNQ) += vlynq/ obj-$(CONFIG_STAGING) += staging/ obj-y += platform/ -- cgit v1.2.1 From 6b1e6cc7855b09a0a9bfa1d9f30172ba366f161c Mon Sep 17 00:00:00 2001 From: Jason Wang Date: Thu, 23 Jun 2016 02:04:32 -0400 Subject: vhost: new device IOTLB API This patch tries to implement an device IOTLB for vhost. This could be used with userspace(qemu) implementation of DMA remapping to emulate an IOMMU for the guest. The idea is simple, cache the translation in a software device IOTLB (which is implemented as an interval tree) in vhost and use vhost_net file descriptor for reporting IOTLB miss and IOTLB update/invalidation. When vhost meets an IOTLB miss, the fault address, size and access can be read from the file. After userspace finishes the translation, it writes the translated address to the vhost_net file to update the device IOTLB. When device IOTLB is enabled by setting VIRTIO_F_IOMMU_PLATFORM all vq addresses set by ioctl are treated as iova instead of virtual address and the accessing can only be done through IOTLB instead of direct userspace memory access. Before each round or vq processing, all vq metadata is prefetched in device IOTLB to make sure no translation fault happens during vq processing. In most cases, virtqueues are contiguous even in virtual address space. The IOTLB translation for virtqueue itself may make it a little slower. We might add fast path cache on top of this patch. Signed-off-by: Jason Wang [mst: use virtio feature bit: VHOST_F_DEVICE_IOTLB -> VIRTIO_F_IOMMU_PLATFORM ] [mst: fix build warnings ] Signed-off-by: Michael S. Tsirkin [ weiyj.lk: missing unlock on error ] Signed-off-by: Wei Yongjun --- drivers/vhost/net.c | 59 ++++- drivers/vhost/vhost.c | 636 ++++++++++++++++++++++++++++++++++++++++++++++---- drivers/vhost/vhost.h | 32 ++- 3 files changed, 677 insertions(+), 50 deletions(-) (limited to 'drivers') diff --git a/drivers/vhost/net.c b/drivers/vhost/net.c index a6b270aff9ef..0965f869dc57 100644 --- a/drivers/vhost/net.c +++ b/drivers/vhost/net.c @@ -61,7 +61,8 @@ MODULE_PARM_DESC(experimental_zcopytx, "Enable Zero Copy TX;" enum { VHOST_NET_FEATURES = VHOST_FEATURES | (1ULL << VHOST_NET_F_VIRTIO_NET_HDR) | - (1ULL << VIRTIO_NET_F_MRG_RXBUF) + (1ULL << VIRTIO_NET_F_MRG_RXBUF) | + (1ULL << VIRTIO_F_IOMMU_PLATFORM) }; enum { @@ -308,7 +309,7 @@ static int vhost_net_tx_get_vq_desc(struct vhost_net *net, { unsigned long uninitialized_var(endtime); int r = vhost_get_vq_desc(vq, vq->iov, ARRAY_SIZE(vq->iov), - out_num, in_num, NULL, NULL); + out_num, in_num, NULL, NULL); if (r == vq->num && vq->busyloop_timeout) { preempt_disable(); @@ -318,7 +319,7 @@ static int vhost_net_tx_get_vq_desc(struct vhost_net *net, cpu_relax_lowlatency(); preempt_enable(); r = vhost_get_vq_desc(vq, vq->iov, ARRAY_SIZE(vq->iov), - out_num, in_num, NULL, NULL); + out_num, in_num, NULL, NULL); } return r; @@ -351,6 +352,9 @@ static void handle_tx(struct vhost_net *net) if (!sock) goto out; + if (!vq_iotlb_prefetch(vq)) + goto out; + vhost_disable_notify(&net->dev, vq); hdr_size = nvq->vhost_hlen; @@ -612,6 +616,10 @@ static void handle_rx(struct vhost_net *net) sock = vq->private_data; if (!sock) goto out; + + if (!vq_iotlb_prefetch(vq)) + goto out; + vhost_disable_notify(&net->dev, vq); vhost_hlen = nvq->vhost_hlen; @@ -1080,10 +1088,14 @@ static int vhost_net_set_features(struct vhost_net *n, u64 features) } 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; + !vhost_log_access_ok(&n->dev)) + goto out_unlock; + + if ((features & (1ULL << VIRTIO_F_IOMMU_PLATFORM))) { + if (vhost_init_device_iotlb(&n->dev, true)) + goto out_unlock; } + for (i = 0; i < VHOST_NET_VQ_MAX; ++i) { mutex_lock(&n->vqs[i].vq.mutex); n->vqs[i].vq.acked_features = features; @@ -1093,6 +1105,10 @@ static int vhost_net_set_features(struct vhost_net *n, u64 features) } mutex_unlock(&n->dev.mutex); return 0; + +out_unlock: + mutex_unlock(&n->dev.mutex); + return -EFAULT; } static long vhost_net_set_owner(struct vhost_net *n) @@ -1166,9 +1182,40 @@ static long vhost_net_compat_ioctl(struct file *f, unsigned int ioctl, } #endif +static ssize_t vhost_net_chr_read_iter(struct kiocb *iocb, struct iov_iter *to) +{ + struct file *file = iocb->ki_filp; + struct vhost_net *n = file->private_data; + struct vhost_dev *dev = &n->dev; + int noblock = file->f_flags & O_NONBLOCK; + + return vhost_chr_read_iter(dev, to, noblock); +} + +static ssize_t vhost_net_chr_write_iter(struct kiocb *iocb, + struct iov_iter *from) +{ + struct file *file = iocb->ki_filp; + struct vhost_net *n = file->private_data; + struct vhost_dev *dev = &n->dev; + + return vhost_chr_write_iter(dev, from); +} + +static unsigned int vhost_net_chr_poll(struct file *file, poll_table *wait) +{ + struct vhost_net *n = file->private_data; + struct vhost_dev *dev = &n->dev; + + return vhost_chr_poll(file, dev, wait); +} + static const struct file_operations vhost_net_fops = { .owner = THIS_MODULE, .release = vhost_net_release, + .read_iter = vhost_net_chr_read_iter, + .write_iter = vhost_net_chr_write_iter, + .poll = vhost_net_chr_poll, .unlocked_ioctl = vhost_net_ioctl, #ifdef CONFIG_COMPAT .compat_ioctl = vhost_net_compat_ioctl, diff --git a/drivers/vhost/vhost.c b/drivers/vhost/vhost.c index 8071f3638db9..d02c1614921f 100644 --- a/drivers/vhost/vhost.c +++ b/drivers/vhost/vhost.c @@ -35,6 +35,10 @@ static ushort max_mem_regions = 64; module_param(max_mem_regions, ushort, 0444); MODULE_PARM_DESC(max_mem_regions, "Maximum number of memory regions in memory map. (default: 64)"); +static int max_iotlb_entries = 2048; +module_param(max_iotlb_entries, int, 0444); +MODULE_PARM_DESC(max_iotlb_entries, + "Maximum number of iotlb entries. (default: 2048)"); enum { VHOST_MEMORY_F_LOG = 0x1, @@ -306,6 +310,7 @@ static void vhost_vq_reset(struct vhost_dev *dev, vhost_disable_cross_endian(vq); vq->busyloop_timeout = 0; vq->umem = NULL; + vq->iotlb = NULL; } static int vhost_worker(void *data) @@ -400,9 +405,14 @@ void vhost_dev_init(struct vhost_dev *dev, dev->log_ctx = NULL; dev->log_file = NULL; dev->umem = NULL; + dev->iotlb = NULL; dev->mm = NULL; dev->worker = NULL; init_llist_head(&dev->work_list); + init_waitqueue_head(&dev->wait); + INIT_LIST_HEAD(&dev->read_list); + INIT_LIST_HEAD(&dev->pending_list); + spin_lock_init(&dev->iotlb_lock); for (i = 0; i < dev->nvqs; ++i) { @@ -550,6 +560,15 @@ void vhost_dev_stop(struct vhost_dev *dev) } EXPORT_SYMBOL_GPL(vhost_dev_stop); +static void vhost_umem_free(struct vhost_umem *umem, + struct vhost_umem_node *node) +{ + vhost_umem_interval_tree_remove(node, &umem->umem_tree); + list_del(&node->link); + kfree(node); + umem->numem--; +} + static void vhost_umem_clean(struct vhost_umem *umem) { struct vhost_umem_node *node, *tmp; @@ -557,14 +576,31 @@ static void vhost_umem_clean(struct vhost_umem *umem) if (!umem) return; - list_for_each_entry_safe(node, tmp, &umem->umem_list, link) { - vhost_umem_interval_tree_remove(node, &umem->umem_tree); - list_del(&node->link); - kvfree(node); - } + list_for_each_entry_safe(node, tmp, &umem->umem_list, link) + vhost_umem_free(umem, node); + kvfree(umem); } +static void vhost_clear_msg(struct vhost_dev *dev) +{ + struct vhost_msg_node *node, *n; + + spin_lock(&dev->iotlb_lock); + + list_for_each_entry_safe(node, n, &dev->read_list, node) { + list_del(&node->node); + kfree(node); + } + + list_for_each_entry_safe(node, n, &dev->pending_list, node) { + list_del(&node->node); + kfree(node); + } + + spin_unlock(&dev->iotlb_lock); +} + /* Caller should have device mutex if and only if locked is set */ void vhost_dev_cleanup(struct vhost_dev *dev, bool locked) { @@ -593,6 +629,10 @@ void vhost_dev_cleanup(struct vhost_dev *dev, bool locked) /* No one will access memory at this point */ vhost_umem_clean(dev->umem); dev->umem = NULL; + vhost_umem_clean(dev->iotlb); + dev->iotlb = NULL; + vhost_clear_msg(dev); + wake_up_interruptible_poll(&dev->wait, POLLIN | POLLRDNORM); WARN_ON(!llist_empty(&dev->work_list)); if (dev->worker) { kthread_stop(dev->worker); @@ -668,28 +708,381 @@ static int memory_access_ok(struct vhost_dev *d, struct vhost_umem *umem, return 1; } -#define vhost_put_user(vq, x, ptr) __put_user(x, ptr) +static int translate_desc(struct vhost_virtqueue *vq, u64 addr, u32 len, + struct iovec iov[], int iov_size, int access); static int vhost_copy_to_user(struct vhost_virtqueue *vq, void *to, const void *from, unsigned size) { - return __copy_to_user(to, from, size); -} + int ret; -#define vhost_get_user(vq, x, ptr) __get_user(x, ptr) + if (!vq->iotlb) + return __copy_to_user(to, from, size); + else { + /* This function should be called after iotlb + * prefetch, which means we're sure that all vq + * could be access through iotlb. So -EAGAIN should + * not happen in this case. + */ + /* TODO: more fast path */ + struct iov_iter t; + ret = translate_desc(vq, (u64)(uintptr_t)to, size, vq->iotlb_iov, + ARRAY_SIZE(vq->iotlb_iov), + VHOST_ACCESS_WO); + if (ret < 0) + goto out; + iov_iter_init(&t, WRITE, vq->iotlb_iov, ret, size); + ret = copy_to_iter(from, size, &t); + if (ret == size) + ret = 0; + } +out: + return ret; +} static int vhost_copy_from_user(struct vhost_virtqueue *vq, void *to, void *from, unsigned size) { - return __copy_from_user(to, from, size); + int ret; + + if (!vq->iotlb) + return __copy_from_user(to, from, size); + else { + /* This function should be called after iotlb + * prefetch, which means we're sure that vq + * could be access through iotlb. So -EAGAIN should + * not happen in this case. + */ + /* TODO: more fast path */ + struct iov_iter f; + ret = translate_desc(vq, (u64)(uintptr_t)from, size, vq->iotlb_iov, + ARRAY_SIZE(vq->iotlb_iov), + VHOST_ACCESS_RO); + if (ret < 0) { + vq_err(vq, "IOTLB translation failure: uaddr " + "%p size 0x%llx\n", from, + (unsigned long long) size); + goto out; + } + iov_iter_init(&f, READ, vq->iotlb_iov, ret, size); + ret = copy_from_iter(to, size, &f); + if (ret == size) + ret = 0; + } + +out: + return ret; +} + +static void __user *__vhost_get_user(struct vhost_virtqueue *vq, + void *addr, unsigned size) +{ + int ret; + + /* This function should be called after iotlb + * prefetch, which means we're sure that vq + * could be access through iotlb. So -EAGAIN should + * not happen in this case. + */ + /* TODO: more fast path */ + ret = translate_desc(vq, (u64)(uintptr_t)addr, size, vq->iotlb_iov, + ARRAY_SIZE(vq->iotlb_iov), + VHOST_ACCESS_RO); + if (ret < 0) { + vq_err(vq, "IOTLB translation failure: uaddr " + "%p size 0x%llx\n", addr, + (unsigned long long) size); + return NULL; + } + + if (ret != 1 || vq->iotlb_iov[0].iov_len != size) { + vq_err(vq, "Non atomic userspace memory access: uaddr " + "%p size 0x%llx\n", addr, + (unsigned long long) size); + return NULL; + } + + return vq->iotlb_iov[0].iov_base; +} + +#define vhost_put_user(vq, x, ptr) \ +({ \ + int ret = -EFAULT; \ + if (!vq->iotlb) { \ + ret = __put_user(x, ptr); \ + } else { \ + __typeof__(ptr) to = \ + (__typeof__(ptr)) __vhost_get_user(vq, ptr, sizeof(*ptr)); \ + if (to != NULL) \ + ret = __put_user(x, to); \ + else \ + ret = -EFAULT; \ + } \ + ret; \ +}) + +#define vhost_get_user(vq, x, ptr) \ +({ \ + int ret; \ + if (!vq->iotlb) { \ + ret = __get_user(x, ptr); \ + } else { \ + __typeof__(ptr) from = \ + (__typeof__(ptr)) __vhost_get_user(vq, ptr, sizeof(*ptr)); \ + if (from != NULL) \ + ret = __get_user(x, from); \ + else \ + ret = -EFAULT; \ + } \ + ret; \ +}) + +static void vhost_dev_lock_vqs(struct vhost_dev *d) +{ + int i = 0; + for (i = 0; i < d->nvqs; ++i) + mutex_lock(&d->vqs[i]->mutex); +} + +static void vhost_dev_unlock_vqs(struct vhost_dev *d) +{ + int i = 0; + for (i = 0; i < d->nvqs; ++i) + mutex_unlock(&d->vqs[i]->mutex); +} + +static int vhost_new_umem_range(struct vhost_umem *umem, + u64 start, u64 size, u64 end, + u64 userspace_addr, int perm) +{ + struct vhost_umem_node *tmp, *node = kmalloc(sizeof(*node), GFP_ATOMIC); + + if (!node) + return -ENOMEM; + + if (umem->numem == max_iotlb_entries) { + tmp = list_first_entry(&umem->umem_list, typeof(*tmp), link); + vhost_umem_free(umem, tmp); + } + + node->start = start; + node->size = size; + node->last = end; + node->userspace_addr = userspace_addr; + node->perm = perm; + INIT_LIST_HEAD(&node->link); + list_add_tail(&node->link, &umem->umem_list); + vhost_umem_interval_tree_insert(node, &umem->umem_tree); + umem->numem++; + + return 0; +} + +static void vhost_del_umem_range(struct vhost_umem *umem, + u64 start, u64 end) +{ + struct vhost_umem_node *node; + + while ((node = vhost_umem_interval_tree_iter_first(&umem->umem_tree, + start, end))) + vhost_umem_free(umem, node); +} + +static void vhost_iotlb_notify_vq(struct vhost_dev *d, + struct vhost_iotlb_msg *msg) +{ + struct vhost_msg_node *node, *n; + + spin_lock(&d->iotlb_lock); + + list_for_each_entry_safe(node, n, &d->pending_list, node) { + struct vhost_iotlb_msg *vq_msg = &node->msg.iotlb; + if (msg->iova <= vq_msg->iova && + msg->iova + msg->size - 1 > vq_msg->iova && + vq_msg->type == VHOST_IOTLB_MISS) { + vhost_poll_queue(&node->vq->poll); + list_del(&node->node); + kfree(node); + } + } + + spin_unlock(&d->iotlb_lock); +} + +static int umem_access_ok(u64 uaddr, u64 size, int access) +{ + unsigned long a = uaddr; + + if ((access & VHOST_ACCESS_RO) && + !access_ok(VERIFY_READ, (void __user *)a, size)) + return -EFAULT; + if ((access & VHOST_ACCESS_WO) && + !access_ok(VERIFY_WRITE, (void __user *)a, size)) + return -EFAULT; + return 0; +} + +int vhost_process_iotlb_msg(struct vhost_dev *dev, + struct vhost_iotlb_msg *msg) +{ + int ret = 0; + + vhost_dev_lock_vqs(dev); + switch (msg->type) { + case VHOST_IOTLB_UPDATE: + if (!dev->iotlb) { + ret = -EFAULT; + break; + } + if (umem_access_ok(msg->uaddr, msg->size, msg->perm)) { + ret = -EFAULT; + break; + } + if (vhost_new_umem_range(dev->iotlb, msg->iova, msg->size, + msg->iova + msg->size - 1, + msg->uaddr, msg->perm)) { + ret = -ENOMEM; + break; + } + vhost_iotlb_notify_vq(dev, msg); + break; + case VHOST_IOTLB_INVALIDATE: + vhost_del_umem_range(dev->iotlb, msg->iova, + msg->iova + msg->size - 1); + break; + default: + ret = -EINVAL; + break; + } + + vhost_dev_unlock_vqs(dev); + return ret; +} +ssize_t vhost_chr_write_iter(struct vhost_dev *dev, + struct iov_iter *from) +{ + struct vhost_msg_node node; + unsigned size = sizeof(struct vhost_msg); + size_t ret; + int err; + + if (iov_iter_count(from) < size) + return 0; + ret = copy_from_iter(&node.msg, size, from); + if (ret != size) + goto done; + + switch (node.msg.type) { + case VHOST_IOTLB_MSG: + err = vhost_process_iotlb_msg(dev, &node.msg.iotlb); + if (err) + ret = err; + break; + default: + ret = -EINVAL; + break; + } + +done: + return ret; +} +EXPORT_SYMBOL(vhost_chr_write_iter); + +unsigned int vhost_chr_poll(struct file *file, struct vhost_dev *dev, + poll_table *wait) +{ + unsigned int mask = 0; + + poll_wait(file, &dev->wait, wait); + + if (!list_empty(&dev->read_list)) + mask |= POLLIN | POLLRDNORM; + + return mask; +} +EXPORT_SYMBOL(vhost_chr_poll); + +ssize_t vhost_chr_read_iter(struct vhost_dev *dev, struct iov_iter *to, + int noblock) +{ + DEFINE_WAIT(wait); + struct vhost_msg_node *node; + ssize_t ret = 0; + unsigned size = sizeof(struct vhost_msg); + + if (iov_iter_count(to) < size) + return 0; + + while (1) { + if (!noblock) + prepare_to_wait(&dev->wait, &wait, + TASK_INTERRUPTIBLE); + + node = vhost_dequeue_msg(dev, &dev->read_list); + if (node) + break; + if (noblock) { + ret = -EAGAIN; + break; + } + if (signal_pending(current)) { + ret = -ERESTARTSYS; + break; + } + if (!dev->iotlb) { + ret = -EBADFD; + break; + } + + schedule(); + } + + if (!noblock) + finish_wait(&dev->wait, &wait); + + if (node) { + ret = copy_to_iter(&node->msg, size, to); + + if (ret != size || node->msg.type != VHOST_IOTLB_MISS) { + kfree(node); + return ret; + } + + vhost_enqueue_msg(dev, &dev->pending_list, node); + } + + return ret; +} +EXPORT_SYMBOL_GPL(vhost_chr_read_iter); + +static int vhost_iotlb_miss(struct vhost_virtqueue *vq, u64 iova, int access) +{ + struct vhost_dev *dev = vq->dev; + struct vhost_msg_node *node; + struct vhost_iotlb_msg *msg; + + node = vhost_new_msg(vq, VHOST_IOTLB_MISS); + if (!node) + return -ENOMEM; + + msg = &node->msg.iotlb; + msg->type = VHOST_IOTLB_MISS; + msg->iova = iova; + msg->perm = access; + + vhost_enqueue_msg(dev, &dev->read_list, node); + + return 0; } 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(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) && @@ -697,6 +1090,54 @@ static int vq_access_ok(struct vhost_virtqueue *vq, unsigned int num, sizeof *used + num * sizeof *used->ring + s); } +static int iotlb_access_ok(struct vhost_virtqueue *vq, + int access, u64 addr, u64 len) +{ + const struct vhost_umem_node *node; + struct vhost_umem *umem = vq->iotlb; + u64 s = 0, size; + + while (len > s) { + node = vhost_umem_interval_tree_iter_first(&umem->umem_tree, + addr, + addr + len - 1); + if (node == NULL || node->start > addr) { + vhost_iotlb_miss(vq, addr, access); + return false; + } else if (!(node->perm & access)) { + /* Report the possible access violation by + * request another translation from userspace. + */ + return false; + } + + size = node->size - addr + node->start; + s += size; + addr += size; + } + + return true; +} + +int vq_iotlb_prefetch(struct vhost_virtqueue *vq) +{ + size_t s = vhost_has_feature(vq, VIRTIO_RING_F_EVENT_IDX) ? 2 : 0; + unsigned int num = vq->num; + + if (!vq->iotlb) + return 1; + + return iotlb_access_ok(vq, VHOST_ACCESS_RO, (u64)(uintptr_t)vq->desc, + num * sizeof *vq->desc) && + iotlb_access_ok(vq, VHOST_ACCESS_RO, (u64)(uintptr_t)vq->avail, + sizeof *vq->avail + + num * sizeof *vq->avail->ring + s) && + iotlb_access_ok(vq, VHOST_ACCESS_WO, (u64)(uintptr_t)vq->used, + sizeof *vq->used + + num * sizeof *vq->used->ring + s); +} +EXPORT_SYMBOL_GPL(vq_iotlb_prefetch); + /* Can we log writes? */ /* Caller should have device mutex but not vq mutex */ int vhost_log_access_ok(struct vhost_dev *dev) @@ -723,16 +1164,35 @@ static int vq_log_access_ok(struct vhost_virtqueue *vq, /* Caller should have vq mutex and device mutex */ int vhost_vq_access_ok(struct vhost_virtqueue *vq) { + if (vq->iotlb) { + /* When device IOTLB was used, the access validation + * will be validated during prefetching. + */ + return 1; + } 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 struct vhost_umem *vhost_umem_alloc(void) +{ + struct vhost_umem *umem = vhost_kvzalloc(sizeof(*umem)); + + if (!umem) + return NULL; + + umem->umem_tree = RB_ROOT; + umem->numem = 0; + INIT_LIST_HEAD(&umem->umem_list); + + return umem; +} + static long vhost_set_memory(struct vhost_dev *d, struct vhost_memory __user *m) { struct vhost_memory mem, *newmem; struct vhost_memory_region *region; - struct vhost_umem_node *node; struct vhost_umem *newumem, *oldumem; unsigned long size = offsetof(struct vhost_memory, regions); int i; @@ -754,28 +1214,23 @@ static long vhost_set_memory(struct vhost_dev *d, struct vhost_memory __user *m) return -EFAULT; } - newumem = vhost_kvzalloc(sizeof(*newumem)); + newumem = vhost_umem_alloc(); if (!newumem) { kvfree(newmem); return -ENOMEM; } - newumem->umem_tree = RB_ROOT; - INIT_LIST_HEAD(&newumem->umem_list); - for (region = newmem->regions; region < newmem->regions + mem.nregions; region++) { - node = vhost_kvzalloc(sizeof(*node)); - if (!node) + if (vhost_new_umem_range(newumem, + region->guest_phys_addr, + region->memory_size, + region->guest_phys_addr + + region->memory_size - 1, + region->userspace_addr, + VHOST_ACCESS_RW)) goto err; - node->start = region->guest_phys_addr; - node->size = region->memory_size; - node->last = node->start + node->size - 1; - node->userspace_addr = region->userspace_addr; - INIT_LIST_HEAD(&node->link); - list_add_tail(&node->link, &newumem->umem_list); - vhost_umem_interval_tree_insert(node, &newumem->umem_tree); } if (!memory_access_ok(d, newumem, 0)) @@ -1019,6 +1474,30 @@ long vhost_vring_ioctl(struct vhost_dev *d, int ioctl, void __user *argp) } EXPORT_SYMBOL_GPL(vhost_vring_ioctl); +int vhost_init_device_iotlb(struct vhost_dev *d, bool enabled) +{ + struct vhost_umem *niotlb, *oiotlb; + int i; + + niotlb = vhost_umem_alloc(); + if (!niotlb) + return -ENOMEM; + + oiotlb = d->iotlb; + d->iotlb = niotlb; + + for (i = 0; i < d->nvqs; ++i) { + mutex_lock(&d->vqs[i]->mutex); + d->vqs[i]->iotlb = niotlb; + mutex_unlock(&d->vqs[i]->mutex); + } + + vhost_umem_clean(oiotlb); + + return 0; +} +EXPORT_SYMBOL_GPL(vhost_init_device_iotlb); + /* Caller must have device mutex */ long vhost_dev_ioctl(struct vhost_dev *d, unsigned int ioctl, void __user *argp) { @@ -1233,15 +1712,20 @@ int vhost_vq_init_access(struct vhost_virtqueue *vq) if (r) goto err; vq->signalled_used_valid = false; - if (!access_ok(VERIFY_READ, &vq->used->idx, sizeof vq->used->idx)) { + if (!vq->iotlb && + !access_ok(VERIFY_READ, &vq->used->idx, sizeof vq->used->idx)) { r = -EFAULT; goto err; } r = vhost_get_user(vq, last_used_idx, &vq->used->idx); - if (r) + if (r) { + vq_err(vq, "Can't access used idx at %p\n", + &vq->used->idx); goto err; + } vq->last_used_idx = vhost16_to_cpu(vq, last_used_idx); return 0; + err: vq->is_le = is_le; return r; @@ -1249,10 +1733,11 @@ err: EXPORT_SYMBOL_GPL(vhost_vq_init_access); static int translate_desc(struct vhost_virtqueue *vq, u64 addr, u32 len, - struct iovec iov[], int iov_size) + struct iovec iov[], int iov_size, int access) { const struct vhost_umem_node *node; - struct vhost_umem *umem = vq->umem; + struct vhost_dev *dev = vq->dev; + struct vhost_umem *umem = dev->iotlb ? dev->iotlb : dev->umem; struct iovec *_iov; u64 s = 0; int ret = 0; @@ -1263,12 +1748,21 @@ static int translate_desc(struct vhost_virtqueue *vq, u64 addr, u32 len, ret = -ENOBUFS; break; } + node = vhost_umem_interval_tree_iter_first(&umem->umem_tree, addr, addr + len - 1); if (node == NULL || node->start > addr) { - ret = -EFAULT; + if (umem != dev->iotlb) { + ret = -EFAULT; + break; + } + ret = -EAGAIN; + break; + } else if (!(node->perm & access)) { + ret = -EPERM; break; } + _iov = iov + ret; size = node->size - addr + node->start; _iov->iov_len = min((u64)len - s, size); @@ -1279,6 +1773,8 @@ static int translate_desc(struct vhost_virtqueue *vq, u64 addr, u32 len, ++ret; } + if (ret == -EAGAIN) + vhost_iotlb_miss(vq, addr, access); return ret; } @@ -1313,7 +1809,7 @@ static int get_indirect(struct vhost_virtqueue *vq, unsigned int i = 0, count, found = 0; u32 len = vhost32_to_cpu(vq, indirect->len); struct iov_iter from; - int ret; + int ret, access; /* Sanity check */ if (unlikely(len % sizeof desc)) { @@ -1325,9 +1821,10 @@ static int get_indirect(struct vhost_virtqueue *vq, } ret = translate_desc(vq, vhost64_to_cpu(vq, indirect->addr), len, vq->indirect, - UIO_MAXIOV); + UIO_MAXIOV, VHOST_ACCESS_RO); if (unlikely(ret < 0)) { - vq_err(vq, "Translation failure %d in indirect.\n", ret); + if (ret != -EAGAIN) + vq_err(vq, "Translation failure %d in indirect.\n", ret); return ret; } iov_iter_init(&from, READ, vq->indirect, ret, len); @@ -1365,16 +1862,22 @@ static int get_indirect(struct vhost_virtqueue *vq, return -EINVAL; } + if (desc.flags & cpu_to_vhost16(vq, VRING_DESC_F_WRITE)) + access = VHOST_ACCESS_WO; + else + access = VHOST_ACCESS_RO; + ret = translate_desc(vq, vhost64_to_cpu(vq, desc.addr), vhost32_to_cpu(vq, desc.len), iov + iov_count, - iov_size - iov_count); + iov_size - iov_count, access); if (unlikely(ret < 0)) { - vq_err(vq, "Translation failure %d indirect idx %d\n", - ret, i); + if (ret != -EAGAIN) + vq_err(vq, "Translation failure %d indirect idx %d\n", + ret, i); return ret; } /* If this is an input descriptor, increment that count. */ - if (desc.flags & cpu_to_vhost16(vq, VRING_DESC_F_WRITE)) { + if (access == VHOST_ACCESS_WO) { *in_num += ret; if (unlikely(log)) { log[*log_num].addr = vhost64_to_cpu(vq, desc.addr); @@ -1413,7 +1916,7 @@ int vhost_get_vq_desc(struct vhost_virtqueue *vq, u16 last_avail_idx; __virtio16 avail_idx; __virtio16 ring_head; - int ret; + int ret, access; /* Check it isn't doing very strange things with descriptor numbers. */ last_avail_idx = vq->last_avail_idx; @@ -1487,22 +1990,28 @@ int vhost_get_vq_desc(struct vhost_virtqueue *vq, out_num, in_num, log, log_num, &desc); if (unlikely(ret < 0)) { - vq_err(vq, "Failure detected " - "in indirect descriptor at idx %d\n", i); + if (ret != -EAGAIN) + vq_err(vq, "Failure detected " + "in indirect descriptor at idx %d\n", i); return ret; } continue; } + if (desc.flags & cpu_to_vhost16(vq, VRING_DESC_F_WRITE)) + access = VHOST_ACCESS_WO; + else + access = VHOST_ACCESS_RO; ret = translate_desc(vq, vhost64_to_cpu(vq, desc.addr), vhost32_to_cpu(vq, desc.len), iov + iov_count, - iov_size - iov_count); + iov_size - iov_count, access); if (unlikely(ret < 0)) { - vq_err(vq, "Translation failure %d descriptor idx %d\n", - ret, i); + if (ret != -EAGAIN) + vq_err(vq, "Translation failure %d descriptor idx %d\n", + ret, i); return ret; } - if (desc.flags & cpu_to_vhost16(vq, VRING_DESC_F_WRITE)) { + if (access == VHOST_ACCESS_WO) { /* If this is an input descriptor, * increment that count. */ *in_num += ret; @@ -1768,6 +2277,47 @@ void vhost_disable_notify(struct vhost_dev *dev, struct vhost_virtqueue *vq) } EXPORT_SYMBOL_GPL(vhost_disable_notify); +/* Create a new message. */ +struct vhost_msg_node *vhost_new_msg(struct vhost_virtqueue *vq, int type) +{ + struct vhost_msg_node *node = kmalloc(sizeof *node, GFP_KERNEL); + if (!node) + return NULL; + node->vq = vq; + node->msg.type = type; + return node; +} +EXPORT_SYMBOL_GPL(vhost_new_msg); + +void vhost_enqueue_msg(struct vhost_dev *dev, struct list_head *head, + struct vhost_msg_node *node) +{ + spin_lock(&dev->iotlb_lock); + list_add_tail(&node->node, head); + spin_unlock(&dev->iotlb_lock); + + wake_up_interruptible_poll(&dev->wait, POLLIN | POLLRDNORM); +} +EXPORT_SYMBOL_GPL(vhost_enqueue_msg); + +struct vhost_msg_node *vhost_dequeue_msg(struct vhost_dev *dev, + struct list_head *head) +{ + struct vhost_msg_node *node = NULL; + + spin_lock(&dev->iotlb_lock); + if (!list_empty(head)) { + node = list_first_entry(head, struct vhost_msg_node, + node); + list_del(&node->node); + } + spin_unlock(&dev->iotlb_lock); + + return node; +} +EXPORT_SYMBOL_GPL(vhost_dequeue_msg); + + static int __init vhost_init(void) { return 0; diff --git a/drivers/vhost/vhost.h b/drivers/vhost/vhost.h index eaaf6df72218..78f3c5fc02e4 100644 --- a/drivers/vhost/vhost.h +++ b/drivers/vhost/vhost.h @@ -65,13 +65,15 @@ struct vhost_umem_node { __u64 last; __u64 size; __u64 userspace_addr; - __u64 flags_padding; + __u32 perm; + __u32 flags_padding; __u64 __subtree_last; }; struct vhost_umem { struct rb_root umem_tree; struct list_head umem_list; + int numem; }; /* The virtqueue structure describes a queue attached to a device. */ @@ -119,10 +121,12 @@ struct vhost_virtqueue { u64 log_addr; struct iovec iov[UIO_MAXIOV]; + struct iovec iotlb_iov[64]; struct iovec *indirect; struct vring_used_elem *heads; /* Protected by virtqueue mutex. */ struct vhost_umem *umem; + struct vhost_umem *iotlb; void *private_data; u64 acked_features; /* Log write descriptors */ @@ -139,6 +143,12 @@ struct vhost_virtqueue { u32 busyloop_timeout; }; +struct vhost_msg_node { + struct vhost_msg msg; + struct vhost_virtqueue *vq; + struct list_head node; +}; + struct vhost_dev { struct mm_struct *mm; struct mutex mutex; @@ -149,6 +159,11 @@ struct vhost_dev { struct llist_head work_list; struct task_struct *worker; struct vhost_umem *umem; + struct vhost_umem *iotlb; + spinlock_t iotlb_lock; + struct list_head read_list; + struct list_head pending_list; + wait_queue_head_t wait; }; void vhost_dev_init(struct vhost_dev *, struct vhost_virtqueue **vqs, int nvqs); @@ -185,6 +200,21 @@ bool vhost_enable_notify(struct vhost_dev *, struct vhost_virtqueue *); int vhost_log_write(struct vhost_virtqueue *vq, struct vhost_log *log, unsigned int log_num, u64 len); +int vq_iotlb_prefetch(struct vhost_virtqueue *vq); + +struct vhost_msg_node *vhost_new_msg(struct vhost_virtqueue *vq, int type); +void vhost_enqueue_msg(struct vhost_dev *dev, + struct list_head *head, + struct vhost_msg_node *node); +struct vhost_msg_node *vhost_dequeue_msg(struct vhost_dev *dev, + struct list_head *head); +unsigned int vhost_chr_poll(struct file *file, struct vhost_dev *dev, + poll_table *wait); +ssize_t vhost_chr_read_iter(struct vhost_dev *dev, struct iov_iter *to, + int noblock); +ssize_t vhost_chr_write_iter(struct vhost_dev *dev, + struct iov_iter *from); +int vhost_init_device_iotlb(struct vhost_dev *d, bool enabled); #define vq_err(vq, fmt, ...) do { \ pr_debug(pr_fmt(fmt), ##__VA_ARGS__); \ -- cgit v1.2.1 From ec33d031a14b3c5dd516627139c9550350dbba3e Mon Sep 17 00:00:00 2001 From: "Michael S. Tsirkin" Date: Mon, 1 Aug 2016 23:20:53 +0300 Subject: vhost: detect 32 bit integer wrap around Detect and fail early if long wrap around is triggered. Signed-off-by: Michael S. Tsirkin --- drivers/vhost/vhost.c | 16 ++++++++++++++-- 1 file changed, 14 insertions(+), 2 deletions(-) (limited to 'drivers') diff --git a/drivers/vhost/vhost.c b/drivers/vhost/vhost.c index d02c1614921f..c6f2d89c0e97 100644 --- a/drivers/vhost/vhost.c +++ b/drivers/vhost/vhost.c @@ -657,6 +657,12 @@ static int log_access_ok(void __user *log_base, u64 addr, unsigned long sz) (sz + VHOST_PAGE_SIZE * 8 - 1) / VHOST_PAGE_SIZE / 8); } +static bool vhost_overflow(u64 uaddr, u64 size) +{ + /* Make sure 64 bit math will not overflow. */ + return uaddr > ULONG_MAX || size > ULONG_MAX || uaddr > ULONG_MAX - size; +} + /* Caller should have vq mutex and device mutex. */ static int vq_memory_access_ok(void __user *log_base, struct vhost_umem *umem, int log_all) @@ -669,9 +675,11 @@ static int vq_memory_access_ok(void __user *log_base, struct vhost_umem *umem, list_for_each_entry(node, &umem->umem_list, link) { unsigned long a = node->userspace_addr; - if (node->size > ULONG_MAX) + if (vhost_overflow(node->userspace_addr, node->size)) return 0; - else if (!access_ok(VERIFY_WRITE, (void __user *)a, + + + if (!access_ok(VERIFY_WRITE, (void __user *)a, node->size)) return 0; else if (log_all && !log_access_ok(log_base, @@ -913,6 +921,10 @@ static int umem_access_ok(u64 uaddr, u64 size, int access) { unsigned long a = uaddr; + /* Make sure 64 bit math will not overflow. */ + if (vhost_overflow(uaddr, size)) + return -EFAULT; + if ((access & VHOST_ACCESS_RO) && !access_ok(VERIFY_READ, (void __user *)a, size)) return -EFAULT; -- cgit v1.2.1 From 4d93824561057d54712066544609dfc7453b210f Mon Sep 17 00:00:00 2001 From: "Michael S. Tsirkin" Date: Tue, 2 Aug 2016 03:03:35 +0300 Subject: vhost: split out vringh Kconfig vringh is pulled in by caif and mic, but the other vhost config does not need to be there. In particular, it makes no sense to have vhost net/scsi/sock under caif/mic. Create a separate Kconfig file and put vringh bits there. Signed-off-by: Michael S. Tsirkin --- drivers/misc/mic/Kconfig | 2 +- drivers/net/caif/Kconfig | 2 +- drivers/vhost/Kconfig | 6 ------ drivers/vhost/Kconfig.vringh | 5 +++++ 4 files changed, 7 insertions(+), 8 deletions(-) create mode 100644 drivers/vhost/Kconfig.vringh (limited to 'drivers') diff --git a/drivers/misc/mic/Kconfig b/drivers/misc/mic/Kconfig index 355bcddb3ed4..6fd9d367dea7 100644 --- a/drivers/misc/mic/Kconfig +++ b/drivers/misc/mic/Kconfig @@ -148,5 +148,5 @@ config VOP . if VOP -source "drivers/vhost/Kconfig" +source "drivers/vhost/Kconfig.vringh" endif diff --git a/drivers/net/caif/Kconfig b/drivers/net/caif/Kconfig index 547098086773..f81df91a9ce1 100644 --- a/drivers/net/caif/Kconfig +++ b/drivers/net/caif/Kconfig @@ -52,5 +52,5 @@ config CAIF_VIRTIO The caif driver for CAIF over Virtio. if CAIF_VIRTIO -source "drivers/vhost/Kconfig" +source "drivers/vhost/Kconfig.vringh" endif diff --git a/drivers/vhost/Kconfig b/drivers/vhost/Kconfig index f77f15bd3b0c..40764ecad9ce 100644 --- a/drivers/vhost/Kconfig +++ b/drivers/vhost/Kconfig @@ -33,12 +33,6 @@ config VHOST_VSOCK To compile this driver as a module, choose M here: the module will be called vhost_vsock. -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--- diff --git a/drivers/vhost/Kconfig.vringh b/drivers/vhost/Kconfig.vringh new file mode 100644 index 000000000000..6a4490c09d7f --- /dev/null +++ b/drivers/vhost/Kconfig.vringh @@ -0,0 +1,5 @@ +config VHOST_RING + tristate + ---help--- + This option is selected by any driver which needs to access + the host side of a virtio ring. -- cgit v1.2.1 From b226acab2f6aaa45c2af27279b63f622b23a44bd Mon Sep 17 00:00:00 2001 From: Wei Yongjun Date: Tue, 2 Aug 2016 13:50:42 +0000 Subject: VSOCK: Use kvfree() Use kvfree() instead of open-coding it. Signed-off-by: Wei Yongjun Signed-off-by: Michael S. Tsirkin --- drivers/vhost/vsock.c | 5 +---- 1 file changed, 1 insertion(+), 4 deletions(-) (limited to 'drivers') diff --git a/drivers/vhost/vsock.c b/drivers/vhost/vsock.c index 028ca16c2d36..0ddf3a2dbfc4 100644 --- a/drivers/vhost/vsock.c +++ b/drivers/vhost/vsock.c @@ -434,10 +434,7 @@ err: static void vhost_vsock_free(struct vhost_vsock *vsock) { - if (is_vmalloc_addr(vsock)) - vfree(vsock); - else - kfree(vsock); + kvfree(vsock); } static int vhost_vsock_dev_open(struct inode *inode, struct file *file) -- cgit v1.2.1