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author | 2019-07-17 11:26:09 -0700 | |
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committer | 2019-07-17 11:26:09 -0700 | |
commit | 3a1d5384b7decbff6519daa9c65a35665e227323 (patch) | |
tree | 7442f1b74d452d82d6702f8cd25173cc81c0c634 /drivers/vhost | |
parent | Merge tag 'vfio-v5.3-rc1' of git://github.com/awilliam/linux-vfio (diff) | |
parent | virtio-mmio: add error check for platform_get_irq (diff) | |
download | linux-3a1d5384b7decbff6519daa9c65a35665e227323.tar.gz linux-3a1d5384b7decbff6519daa9c65a35665e227323.tar.bz2 linux-3a1d5384b7decbff6519daa9c65a35665e227323.zip |
Merge tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost
Pull virtio, vhost updates from Michael Tsirkin:
"Fixes, features, performance:
- new iommu device
- vhost guest memory access using vmap (just meta-data for now)
- minor fixes"
* tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost:
virtio-mmio: add error check for platform_get_irq
scsi: virtio_scsi: Use struct_size() helper
iommu/virtio: Add event queue
iommu/virtio: Add probe request
iommu: Add virtio-iommu driver
PCI: OF: Initialize dev->fwnode appropriately
of: Allow the iommu-map property to omit untranslated devices
dt-bindings: virtio: Add virtio-pci-iommu node
dt-bindings: virtio-mmio: Add IOMMU description
vhost: fix clang build warning
vhost: access vq metadata through kernel virtual address
vhost: factor out setting vring addr and num
vhost: introduce helpers to get the size of metadata area
vhost: rename vq_iotlb_prefetch() to vq_meta_prefetch()
vhost: fine grain userspace memory accessors
vhost: generalize adding used elem
Diffstat (limited to 'drivers/vhost')
-rw-r--r-- | drivers/vhost/net.c | 4 | ||||
-rw-r--r-- | drivers/vhost/vhost.c | 850 | ||||
-rw-r--r-- | drivers/vhost/vhost.h | 43 |
3 files changed, 771 insertions, 126 deletions
diff --git a/drivers/vhost/net.c b/drivers/vhost/net.c index 247e5585af5d..1a2dd53caade 100644 --- a/drivers/vhost/net.c +++ b/drivers/vhost/net.c @@ -956,7 +956,7 @@ static void handle_tx(struct vhost_net *net) if (!sock) goto out; - if (!vq_iotlb_prefetch(vq)) + if (!vq_meta_prefetch(vq)) goto out; vhost_disable_notify(&net->dev, vq); @@ -1125,7 +1125,7 @@ static void handle_rx(struct vhost_net *net) if (!sock) goto out; - if (!vq_iotlb_prefetch(vq)) + if (!vq_meta_prefetch(vq)) goto out; vhost_disable_notify(&net->dev, vq); diff --git a/drivers/vhost/vhost.c b/drivers/vhost/vhost.c index ff8892c38666..0536f8526359 100644 --- a/drivers/vhost/vhost.c +++ b/drivers/vhost/vhost.c @@ -298,6 +298,160 @@ static void vhost_vq_meta_reset(struct vhost_dev *d) __vhost_vq_meta_reset(d->vqs[i]); } +#if VHOST_ARCH_CAN_ACCEL_UACCESS +static void vhost_map_unprefetch(struct vhost_map *map) +{ + kfree(map->pages); + map->pages = NULL; + map->npages = 0; + map->addr = NULL; +} + +static void vhost_uninit_vq_maps(struct vhost_virtqueue *vq) +{ + struct vhost_map *map[VHOST_NUM_ADDRS]; + int i; + + spin_lock(&vq->mmu_lock); + for (i = 0; i < VHOST_NUM_ADDRS; i++) { + map[i] = rcu_dereference_protected(vq->maps[i], + lockdep_is_held(&vq->mmu_lock)); + if (map[i]) + rcu_assign_pointer(vq->maps[i], NULL); + } + spin_unlock(&vq->mmu_lock); + + synchronize_rcu(); + + for (i = 0; i < VHOST_NUM_ADDRS; i++) + if (map[i]) + vhost_map_unprefetch(map[i]); + +} + +static void vhost_reset_vq_maps(struct vhost_virtqueue *vq) +{ + int i; + + vhost_uninit_vq_maps(vq); + for (i = 0; i < VHOST_NUM_ADDRS; i++) + vq->uaddrs[i].size = 0; +} + +static bool vhost_map_range_overlap(struct vhost_uaddr *uaddr, + unsigned long start, + unsigned long end) +{ + if (unlikely(!uaddr->size)) + return false; + + return !(end < uaddr->uaddr || start > uaddr->uaddr - 1 + uaddr->size); +} + +static void vhost_invalidate_vq_start(struct vhost_virtqueue *vq, + int index, + unsigned long start, + unsigned long end) +{ + struct vhost_uaddr *uaddr = &vq->uaddrs[index]; + struct vhost_map *map; + int i; + + if (!vhost_map_range_overlap(uaddr, start, end)) + return; + + spin_lock(&vq->mmu_lock); + ++vq->invalidate_count; + + map = rcu_dereference_protected(vq->maps[index], + lockdep_is_held(&vq->mmu_lock)); + if (map) { + if (uaddr->write) { + for (i = 0; i < map->npages; i++) + set_page_dirty(map->pages[i]); + } + rcu_assign_pointer(vq->maps[index], NULL); + } + spin_unlock(&vq->mmu_lock); + + if (map) { + synchronize_rcu(); + vhost_map_unprefetch(map); + } +} + +static void vhost_invalidate_vq_end(struct vhost_virtqueue *vq, + int index, + unsigned long start, + unsigned long end) +{ + if (!vhost_map_range_overlap(&vq->uaddrs[index], start, end)) + return; + + spin_lock(&vq->mmu_lock); + --vq->invalidate_count; + spin_unlock(&vq->mmu_lock); +} + +static int vhost_invalidate_range_start(struct mmu_notifier *mn, + const struct mmu_notifier_range *range) +{ + struct vhost_dev *dev = container_of(mn, struct vhost_dev, + mmu_notifier); + int i, j; + + if (!mmu_notifier_range_blockable(range)) + return -EAGAIN; + + for (i = 0; i < dev->nvqs; i++) { + struct vhost_virtqueue *vq = dev->vqs[i]; + + for (j = 0; j < VHOST_NUM_ADDRS; j++) + vhost_invalidate_vq_start(vq, j, + range->start, + range->end); + } + + return 0; +} + +static void vhost_invalidate_range_end(struct mmu_notifier *mn, + const struct mmu_notifier_range *range) +{ + struct vhost_dev *dev = container_of(mn, struct vhost_dev, + mmu_notifier); + int i, j; + + for (i = 0; i < dev->nvqs; i++) { + struct vhost_virtqueue *vq = dev->vqs[i]; + + for (j = 0; j < VHOST_NUM_ADDRS; j++) + vhost_invalidate_vq_end(vq, j, + range->start, + range->end); + } +} + +static const struct mmu_notifier_ops vhost_mmu_notifier_ops = { + .invalidate_range_start = vhost_invalidate_range_start, + .invalidate_range_end = vhost_invalidate_range_end, +}; + +static void vhost_init_maps(struct vhost_dev *dev) +{ + struct vhost_virtqueue *vq; + int i, j; + + dev->mmu_notifier.ops = &vhost_mmu_notifier_ops; + + for (i = 0; i < dev->nvqs; ++i) { + vq = dev->vqs[i]; + for (j = 0; j < VHOST_NUM_ADDRS; j++) + RCU_INIT_POINTER(vq->maps[j], NULL); + } +} +#endif + static void vhost_vq_reset(struct vhost_dev *dev, struct vhost_virtqueue *vq) { @@ -326,7 +480,11 @@ static void vhost_vq_reset(struct vhost_dev *dev, vq->busyloop_timeout = 0; vq->umem = NULL; vq->iotlb = NULL; + vq->invalidate_count = 0; __vhost_vq_meta_reset(vq); +#if VHOST_ARCH_CAN_ACCEL_UACCESS + vhost_reset_vq_maps(vq); +#endif } static int vhost_worker(void *data) @@ -427,6 +585,32 @@ bool vhost_exceeds_weight(struct vhost_virtqueue *vq, } EXPORT_SYMBOL_GPL(vhost_exceeds_weight); +static size_t vhost_get_avail_size(struct vhost_virtqueue *vq, + unsigned int num) +{ + size_t event __maybe_unused = + vhost_has_feature(vq, VIRTIO_RING_F_EVENT_IDX) ? 2 : 0; + + return sizeof(*vq->avail) + + sizeof(*vq->avail->ring) * num + event; +} + +static size_t vhost_get_used_size(struct vhost_virtqueue *vq, + unsigned int num) +{ + size_t event __maybe_unused = + vhost_has_feature(vq, VIRTIO_RING_F_EVENT_IDX) ? 2 : 0; + + return sizeof(*vq->used) + + sizeof(*vq->used->ring) * num + event; +} + +static size_t vhost_get_desc_size(struct vhost_virtqueue *vq, + unsigned int num) +{ + return sizeof(*vq->desc) * num; +} + void vhost_dev_init(struct vhost_dev *dev, struct vhost_virtqueue **vqs, int nvqs, int iov_limit, int weight, int byte_weight) @@ -450,7 +634,9 @@ void vhost_dev_init(struct vhost_dev *dev, INIT_LIST_HEAD(&dev->read_list); INIT_LIST_HEAD(&dev->pending_list); spin_lock_init(&dev->iotlb_lock); - +#if VHOST_ARCH_CAN_ACCEL_UACCESS + vhost_init_maps(dev); +#endif for (i = 0; i < dev->nvqs; ++i) { vq = dev->vqs[i]; @@ -459,6 +645,7 @@ void vhost_dev_init(struct vhost_dev *dev, vq->heads = NULL; vq->dev = dev; mutex_init(&vq->mutex); + spin_lock_init(&vq->mmu_lock); vhost_vq_reset(dev, vq); if (vq->handle_kick) vhost_poll_init(&vq->poll, vq->handle_kick, @@ -538,7 +725,18 @@ long vhost_dev_set_owner(struct vhost_dev *dev) if (err) goto err_cgroup; +#if VHOST_ARCH_CAN_ACCEL_UACCESS + err = mmu_notifier_register(&dev->mmu_notifier, dev->mm); + if (err) + goto err_mmu_notifier; +#endif + return 0; + +#if VHOST_ARCH_CAN_ACCEL_UACCESS +err_mmu_notifier: + vhost_dev_free_iovecs(dev); +#endif err_cgroup: kthread_stop(worker); dev->worker = NULL; @@ -629,6 +827,107 @@ static void vhost_clear_msg(struct vhost_dev *dev) spin_unlock(&dev->iotlb_lock); } +#if VHOST_ARCH_CAN_ACCEL_UACCESS +static void vhost_setup_uaddr(struct vhost_virtqueue *vq, + int index, unsigned long uaddr, + size_t size, bool write) +{ + struct vhost_uaddr *addr = &vq->uaddrs[index]; + + addr->uaddr = uaddr; + addr->size = size; + addr->write = write; +} + +static void vhost_setup_vq_uaddr(struct vhost_virtqueue *vq) +{ + vhost_setup_uaddr(vq, VHOST_ADDR_DESC, + (unsigned long)vq->desc, + vhost_get_desc_size(vq, vq->num), + false); + vhost_setup_uaddr(vq, VHOST_ADDR_AVAIL, + (unsigned long)vq->avail, + vhost_get_avail_size(vq, vq->num), + false); + vhost_setup_uaddr(vq, VHOST_ADDR_USED, + (unsigned long)vq->used, + vhost_get_used_size(vq, vq->num), + true); +} + +static int vhost_map_prefetch(struct vhost_virtqueue *vq, + int index) +{ + struct vhost_map *map; + struct vhost_uaddr *uaddr = &vq->uaddrs[index]; + struct page **pages; + int npages = DIV_ROUND_UP(uaddr->size, PAGE_SIZE); + int npinned; + void *vaddr, *v; + int err; + int i; + + spin_lock(&vq->mmu_lock); + + err = -EFAULT; + if (vq->invalidate_count) + goto err; + + err = -ENOMEM; + map = kmalloc(sizeof(*map), GFP_ATOMIC); + if (!map) + goto err; + + pages = kmalloc_array(npages, sizeof(struct page *), GFP_ATOMIC); + if (!pages) + goto err_pages; + + err = EFAULT; + npinned = __get_user_pages_fast(uaddr->uaddr, npages, + uaddr->write, pages); + if (npinned > 0) + release_pages(pages, npinned); + if (npinned != npages) + goto err_gup; + + for (i = 0; i < npinned; i++) + if (PageHighMem(pages[i])) + goto err_gup; + + vaddr = v = page_address(pages[0]); + + /* For simplicity, fallback to userspace address if VA is not + * contigious. + */ + for (i = 1; i < npinned; i++) { + v += PAGE_SIZE; + if (v != page_address(pages[i])) + goto err_gup; + } + + map->addr = vaddr + (uaddr->uaddr & (PAGE_SIZE - 1)); + map->npages = npages; + map->pages = pages; + + rcu_assign_pointer(vq->maps[index], map); + /* No need for a synchronize_rcu(). This function should be + * called by dev->worker so we are serialized with all + * readers. + */ + spin_unlock(&vq->mmu_lock); + + return 0; + +err_gup: + kfree(pages); +err_pages: + kfree(map); +err: + spin_unlock(&vq->mmu_lock); + return err; +} +#endif + void vhost_dev_cleanup(struct vhost_dev *dev) { int i; @@ -658,8 +957,16 @@ void vhost_dev_cleanup(struct vhost_dev *dev) kthread_stop(dev->worker); dev->worker = NULL; } - if (dev->mm) + if (dev->mm) { +#if VHOST_ARCH_CAN_ACCEL_UACCESS + mmu_notifier_unregister(&dev->mmu_notifier, dev->mm); +#endif mmput(dev->mm); + } +#if VHOST_ARCH_CAN_ACCEL_UACCESS + for (i = 0; i < dev->nvqs; i++) + vhost_uninit_vq_maps(dev->vqs[i]); +#endif dev->mm = NULL; } EXPORT_SYMBOL_GPL(vhost_dev_cleanup); @@ -886,6 +1193,113 @@ static inline void __user *__vhost_get_user(struct vhost_virtqueue *vq, ret; \ }) +static inline int vhost_put_avail_event(struct vhost_virtqueue *vq) +{ +#if VHOST_ARCH_CAN_ACCEL_UACCESS + struct vhost_map *map; + struct vring_used *used; + + if (!vq->iotlb) { + rcu_read_lock(); + + map = rcu_dereference(vq->maps[VHOST_ADDR_USED]); + if (likely(map)) { + used = map->addr; + *((__virtio16 *)&used->ring[vq->num]) = + cpu_to_vhost16(vq, vq->avail_idx); + rcu_read_unlock(); + return 0; + } + + rcu_read_unlock(); + } +#endif + + return vhost_put_user(vq, cpu_to_vhost16(vq, vq->avail_idx), + vhost_avail_event(vq)); +} + +static inline int vhost_put_used(struct vhost_virtqueue *vq, + struct vring_used_elem *head, int idx, + int count) +{ +#if VHOST_ARCH_CAN_ACCEL_UACCESS + struct vhost_map *map; + struct vring_used *used; + size_t size; + + if (!vq->iotlb) { + rcu_read_lock(); + + map = rcu_dereference(vq->maps[VHOST_ADDR_USED]); + if (likely(map)) { + used = map->addr; + size = count * sizeof(*head); + memcpy(used->ring + idx, head, size); + rcu_read_unlock(); + return 0; + } + + rcu_read_unlock(); + } +#endif + + return vhost_copy_to_user(vq, vq->used->ring + idx, head, + count * sizeof(*head)); +} + +static inline int vhost_put_used_flags(struct vhost_virtqueue *vq) + +{ +#if VHOST_ARCH_CAN_ACCEL_UACCESS + struct vhost_map *map; + struct vring_used *used; + + if (!vq->iotlb) { + rcu_read_lock(); + + map = rcu_dereference(vq->maps[VHOST_ADDR_USED]); + if (likely(map)) { + used = map->addr; + used->flags = cpu_to_vhost16(vq, vq->used_flags); + rcu_read_unlock(); + return 0; + } + + rcu_read_unlock(); + } +#endif + + return vhost_put_user(vq, cpu_to_vhost16(vq, vq->used_flags), + &vq->used->flags); +} + +static inline int vhost_put_used_idx(struct vhost_virtqueue *vq) + +{ +#if VHOST_ARCH_CAN_ACCEL_UACCESS + struct vhost_map *map; + struct vring_used *used; + + if (!vq->iotlb) { + rcu_read_lock(); + + map = rcu_dereference(vq->maps[VHOST_ADDR_USED]); + if (likely(map)) { + used = map->addr; + used->idx = cpu_to_vhost16(vq, vq->last_used_idx); + rcu_read_unlock(); + return 0; + } + + rcu_read_unlock(); + } +#endif + + return vhost_put_user(vq, cpu_to_vhost16(vq, vq->last_used_idx), + &vq->used->idx); +} + #define vhost_get_user(vq, x, ptr, type) \ ({ \ int ret; \ @@ -924,6 +1338,155 @@ static void vhost_dev_unlock_vqs(struct vhost_dev *d) mutex_unlock(&d->vqs[i]->mutex); } +static inline int vhost_get_avail_idx(struct vhost_virtqueue *vq, + __virtio16 *idx) +{ +#if VHOST_ARCH_CAN_ACCEL_UACCESS + struct vhost_map *map; + struct vring_avail *avail; + + if (!vq->iotlb) { + rcu_read_lock(); + + map = rcu_dereference(vq->maps[VHOST_ADDR_AVAIL]); + if (likely(map)) { + avail = map->addr; + *idx = avail->idx; + rcu_read_unlock(); + return 0; + } + + rcu_read_unlock(); + } +#endif + + return vhost_get_avail(vq, *idx, &vq->avail->idx); +} + +static inline int vhost_get_avail_head(struct vhost_virtqueue *vq, + __virtio16 *head, int idx) +{ +#if VHOST_ARCH_CAN_ACCEL_UACCESS + struct vhost_map *map; + struct vring_avail *avail; + + if (!vq->iotlb) { + rcu_read_lock(); + + map = rcu_dereference(vq->maps[VHOST_ADDR_AVAIL]); + if (likely(map)) { + avail = map->addr; + *head = avail->ring[idx & (vq->num - 1)]; + rcu_read_unlock(); + return 0; + } + + rcu_read_unlock(); + } +#endif + + return vhost_get_avail(vq, *head, + &vq->avail->ring[idx & (vq->num - 1)]); +} + +static inline int vhost_get_avail_flags(struct vhost_virtqueue *vq, + __virtio16 *flags) +{ +#if VHOST_ARCH_CAN_ACCEL_UACCESS + struct vhost_map *map; + struct vring_avail *avail; + + if (!vq->iotlb) { + rcu_read_lock(); + + map = rcu_dereference(vq->maps[VHOST_ADDR_AVAIL]); + if (likely(map)) { + avail = map->addr; + *flags = avail->flags; + rcu_read_unlock(); + return 0; + } + + rcu_read_unlock(); + } +#endif + + return vhost_get_avail(vq, *flags, &vq->avail->flags); +} + +static inline int vhost_get_used_event(struct vhost_virtqueue *vq, + __virtio16 *event) +{ +#if VHOST_ARCH_CAN_ACCEL_UACCESS + struct vhost_map *map; + struct vring_avail *avail; + + if (!vq->iotlb) { + rcu_read_lock(); + map = rcu_dereference(vq->maps[VHOST_ADDR_AVAIL]); + if (likely(map)) { + avail = map->addr; + *event = (__virtio16)avail->ring[vq->num]; + rcu_read_unlock(); + return 0; + } + rcu_read_unlock(); + } +#endif + + return vhost_get_avail(vq, *event, vhost_used_event(vq)); +} + +static inline int vhost_get_used_idx(struct vhost_virtqueue *vq, + __virtio16 *idx) +{ +#if VHOST_ARCH_CAN_ACCEL_UACCESS + struct vhost_map *map; + struct vring_used *used; + + if (!vq->iotlb) { + rcu_read_lock(); + + map = rcu_dereference(vq->maps[VHOST_ADDR_USED]); + if (likely(map)) { + used = map->addr; + *idx = used->idx; + rcu_read_unlock(); + return 0; + } + + rcu_read_unlock(); + } +#endif + + return vhost_get_used(vq, *idx, &vq->used->idx); +} + +static inline int vhost_get_desc(struct vhost_virtqueue *vq, + struct vring_desc *desc, int idx) +{ +#if VHOST_ARCH_CAN_ACCEL_UACCESS + struct vhost_map *map; + struct vring_desc *d; + + if (!vq->iotlb) { + rcu_read_lock(); + + map = rcu_dereference(vq->maps[VHOST_ADDR_DESC]); + if (likely(map)) { + d = map->addr; + *desc = *(d + idx); + rcu_read_unlock(); + return 0; + } + + rcu_read_unlock(); + } +#endif + + return vhost_copy_from_user(vq, desc, vq->desc + idx, sizeof(*desc)); +} + static int vhost_new_umem_range(struct vhost_umem *umem, u64 start, u64 size, u64 end, u64 userspace_addr, int perm) @@ -1209,13 +1772,9 @@ static bool vq_access_ok(struct vhost_virtqueue *vq, unsigned int num, struct vring_used __user *used) { - size_t s __maybe_unused = vhost_has_feature(vq, VIRTIO_RING_F_EVENT_IDX) ? 2 : 0; - - return access_ok(desc, num * sizeof *desc) && - access_ok(avail, - sizeof *avail + num * sizeof *avail->ring + s) && - access_ok(used, - sizeof *used + num * sizeof *used->ring + s); + return access_ok(desc, vhost_get_desc_size(vq, num)) && + access_ok(avail, vhost_get_avail_size(vq, num)) && + access_ok(used, vhost_get_used_size(vq, num)); } static void vhost_vq_meta_update(struct vhost_virtqueue *vq, @@ -1265,26 +1824,42 @@ static bool iotlb_access_ok(struct vhost_virtqueue *vq, return true; } -int vq_iotlb_prefetch(struct vhost_virtqueue *vq) +#if VHOST_ARCH_CAN_ACCEL_UACCESS +static void vhost_vq_map_prefetch(struct vhost_virtqueue *vq) +{ + struct vhost_map __rcu *map; + int i; + + for (i = 0; i < VHOST_NUM_ADDRS; i++) { + rcu_read_lock(); + map = rcu_dereference(vq->maps[i]); + rcu_read_unlock(); + if (unlikely(!map)) + vhost_map_prefetch(vq, i); + } +} +#endif + +int vq_meta_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) + if (!vq->iotlb) { +#if VHOST_ARCH_CAN_ACCEL_UACCESS + vhost_vq_map_prefetch(vq); +#endif return 1; + } return iotlb_access_ok(vq, VHOST_ACCESS_RO, (u64)(uintptr_t)vq->desc, - num * sizeof(*vq->desc), VHOST_ADDR_DESC) && + vhost_get_desc_size(vq, num), VHOST_ADDR_DESC) && iotlb_access_ok(vq, VHOST_ACCESS_RO, (u64)(uintptr_t)vq->avail, - sizeof *vq->avail + - num * sizeof(*vq->avail->ring) + s, + vhost_get_avail_size(vq, num), VHOST_ADDR_AVAIL) && iotlb_access_ok(vq, VHOST_ACCESS_WO, (u64)(uintptr_t)vq->used, - sizeof *vq->used + - num * sizeof(*vq->used->ring) + s, - VHOST_ADDR_USED); + vhost_get_used_size(vq, num), VHOST_ADDR_USED); } -EXPORT_SYMBOL_GPL(vq_iotlb_prefetch); +EXPORT_SYMBOL_GPL(vq_meta_prefetch); /* Can we log writes? */ /* Caller should have device mutex but not vq mutex */ @@ -1299,13 +1874,10 @@ EXPORT_SYMBOL_GPL(vhost_log_access_ok); static bool vq_log_access_ok(struct vhost_virtqueue *vq, void __user *log_base) { - size_t s = vhost_has_feature(vq, VIRTIO_RING_F_EVENT_IDX) ? 2 : 0; - 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 + - vq->num * sizeof *vq->used->ring + s)); + vhost_get_used_size(vq, vq->num))); } /* Can we start vq? */ @@ -1405,6 +1977,121 @@ err: return -EFAULT; } +static long vhost_vring_set_num(struct vhost_dev *d, + struct vhost_virtqueue *vq, + void __user *argp) +{ + struct vhost_vring_state s; + + /* Resizing ring with an active backend? + * You don't want to do that. */ + if (vq->private_data) + return -EBUSY; + + if (copy_from_user(&s, argp, sizeof s)) + return -EFAULT; + + if (!s.num || s.num > 0xffff || (s.num & (s.num - 1))) + return -EINVAL; + vq->num = s.num; + + return 0; +} + +static long vhost_vring_set_addr(struct vhost_dev *d, + struct vhost_virtqueue *vq, + void __user *argp) +{ + struct vhost_vring_addr a; + + if (copy_from_user(&a, argp, sizeof a)) + return -EFAULT; + if (a.flags & ~(0x1 << VHOST_VRING_F_LOG)) + return -EOPNOTSUPP; + + /* For 32bit, verify that the top 32bits of the user + data are set to zero. */ + if ((u64)(unsigned long)a.desc_user_addr != a.desc_user_addr || + (u64)(unsigned long)a.used_user_addr != a.used_user_addr || + (u64)(unsigned long)a.avail_user_addr != a.avail_user_addr) + return -EFAULT; + + /* Make sure it's safe to cast pointers to vring types. */ + BUILD_BUG_ON(__alignof__ *vq->avail > VRING_AVAIL_ALIGN_SIZE); + BUILD_BUG_ON(__alignof__ *vq->used > VRING_USED_ALIGN_SIZE); + if ((a.avail_user_addr & (VRING_AVAIL_ALIGN_SIZE - 1)) || + (a.used_user_addr & (VRING_USED_ALIGN_SIZE - 1)) || + (a.log_guest_addr & (VRING_USED_ALIGN_SIZE - 1))) + return -EINVAL; + + /* We only verify access here if backend is configured. + * 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(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)) + return -EINVAL; + + /* Also validate log access for used ring if enabled. */ + if ((a.flags & (0x1 << VHOST_VRING_F_LOG)) && + !log_access_ok(vq->log_base, a.log_guest_addr, + sizeof *vq->used + + vq->num * sizeof *vq->used->ring)) + return -EINVAL; + } + + vq->log_used = !!(a.flags & (0x1 << VHOST_VRING_F_LOG)); + vq->desc = (void __user *)(unsigned long)a.desc_user_addr; + vq->avail = (void __user *)(unsigned long)a.avail_user_addr; + vq->log_addr = a.log_guest_addr; + vq->used = (void __user *)(unsigned long)a.used_user_addr; + + return 0; +} + +static long vhost_vring_set_num_addr(struct vhost_dev *d, + struct vhost_virtqueue *vq, + unsigned int ioctl, + void __user *argp) +{ + long r; + + mutex_lock(&vq->mutex); + +#if VHOST_ARCH_CAN_ACCEL_UACCESS + /* Unregister MMU notifer to allow invalidation callback + * can access vq->uaddrs[] without holding a lock. + */ + if (d->mm) + mmu_notifier_unregister(&d->mmu_notifier, d->mm); + + vhost_uninit_vq_maps(vq); +#endif + + switch (ioctl) { + case VHOST_SET_VRING_NUM: + r = vhost_vring_set_num(d, vq, argp); + break; + case VHOST_SET_VRING_ADDR: + r = vhost_vring_set_addr(d, vq, argp); + break; + default: + BUG(); + } + +#if VHOST_ARCH_CAN_ACCEL_UACCESS + vhost_setup_vq_uaddr(vq); + + if (d->mm) + mmu_notifier_register(&d->mmu_notifier, d->mm); +#endif + + mutex_unlock(&vq->mutex); + + return r; +} long vhost_vring_ioctl(struct vhost_dev *d, unsigned int ioctl, void __user *argp) { struct file *eventfp, *filep = NULL; @@ -1414,7 +2101,6 @@ long vhost_vring_ioctl(struct vhost_dev *d, unsigned int ioctl, void __user *arg struct vhost_virtqueue *vq; struct vhost_vring_state s; struct vhost_vring_file f; - struct vhost_vring_addr a; u32 idx; long r; @@ -1427,26 +2113,14 @@ long vhost_vring_ioctl(struct vhost_dev *d, unsigned int ioctl, void __user *arg idx = array_index_nospec(idx, d->nvqs); vq = d->vqs[idx]; + if (ioctl == VHOST_SET_VRING_NUM || + ioctl == VHOST_SET_VRING_ADDR) { + return vhost_vring_set_num_addr(d, vq, ioctl, argp); + } + mutex_lock(&vq->mutex); switch (ioctl) { - case VHOST_SET_VRING_NUM: - /* Resizing ring with an active backend? - * You don't want to do that. */ - if (vq->private_data) { - r = -EBUSY; - break; - } - if (copy_from_user(&s, argp, sizeof s)) { - r = -EFAULT; - break; - } - if (!s.num || s.num > 0xffff || (s.num & (s.num - 1))) { - r = -EINVAL; - break; - } - vq->num = s.num; - break; case VHOST_SET_VRING_BASE: /* Moving base with an active backend? * You don't want to do that. */ @@ -1472,62 +2146,6 @@ long vhost_vring_ioctl(struct vhost_dev *d, unsigned int ioctl, void __user *arg if (copy_to_user(argp, &s, sizeof s)) r = -EFAULT; break; - case VHOST_SET_VRING_ADDR: - if (copy_from_user(&a, argp, sizeof a)) { - r = -EFAULT; - break; - } - if (a.flags & ~(0x1 << VHOST_VRING_F_LOG)) { - r = -EOPNOTSUPP; - break; - } - /* For 32bit, verify that the top 32bits of the user - data are set to zero. */ - if ((u64)(unsigned long)a.desc_user_addr != a.desc_user_addr || - (u64)(unsigned long)a.used_user_addr != a.used_user_addr || - (u64)(unsigned long)a.avail_user_addr != a.avail_user_addr) { - r = -EFAULT; - break; - } - - /* Make sure it's safe to cast pointers to vring types. */ - BUILD_BUG_ON(__alignof__ *vq->avail > VRING_AVAIL_ALIGN_SIZE); - BUILD_BUG_ON(__alignof__ *vq->used > VRING_USED_ALIGN_SIZE); - if ((a.avail_user_addr & (VRING_AVAIL_ALIGN_SIZE - 1)) || - (a.used_user_addr & (VRING_USED_ALIGN_SIZE - 1)) || - (a.log_guest_addr & (VRING_USED_ALIGN_SIZE - 1))) { - r = -EINVAL; - break; - } - - /* We only verify access here if backend is configured. - * 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(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)) { - r = -EINVAL; - break; - } - - /* Also validate log access for used ring if enabled. */ - if ((a.flags & (0x1 << VHOST_VRING_F_LOG)) && - !log_access_ok(vq->log_base, a.log_guest_addr, - sizeof *vq->used + - vq->num * sizeof *vq->used->ring)) { - r = -EINVAL; - break; - } - } - - vq->log_used = !!(a.flags & (0x1 << VHOST_VRING_F_LOG)); - vq->desc = (void __user *)(unsigned long)a.desc_user_addr; - vq->avail = (void __user *)(unsigned long)a.avail_user_addr; - vq->log_addr = a.log_guest_addr; - vq->used = (void __user *)(unsigned long)a.used_user_addr; - break; case VHOST_SET_VRING_KICK: if (copy_from_user(&f, argp, sizeof f)) { r = -EFAULT; @@ -1861,8 +2479,7 @@ EXPORT_SYMBOL_GPL(vhost_log_write); static int vhost_update_used_flags(struct vhost_virtqueue *vq) { void __user *used; - if (vhost_put_user(vq, cpu_to_vhost16(vq, vq->used_flags), - &vq->used->flags) < 0) + if (vhost_put_used_flags(vq)) return -EFAULT; if (unlikely(vq->log_used)) { /* Make sure the flag is seen before log. */ @@ -1879,8 +2496,7 @@ static int vhost_update_used_flags(struct vhost_virtqueue *vq) static int vhost_update_avail_event(struct vhost_virtqueue *vq, u16 avail_event) { - if (vhost_put_user(vq, cpu_to_vhost16(vq, vq->avail_idx), - vhost_avail_event(vq))) + if (vhost_put_avail_event(vq)) return -EFAULT; if (unlikely(vq->log_used)) { void __user *used; @@ -1916,7 +2532,7 @@ int vhost_vq_init_access(struct vhost_virtqueue *vq) r = -EFAULT; goto err; } - r = vhost_get_used(vq, last_used_idx, &vq->used->idx); + r = vhost_get_used_idx(vq, &last_used_idx); if (r) { vq_err(vq, "Can't access used idx at %p\n", &vq->used->idx); @@ -2115,7 +2731,7 @@ int vhost_get_vq_desc(struct vhost_virtqueue *vq, last_avail_idx = vq->last_avail_idx; if (vq->avail_idx == vq->last_avail_idx) { - if (unlikely(vhost_get_avail(vq, avail_idx, &vq->avail->idx))) { + if (unlikely(vhost_get_avail_idx(vq, &avail_idx))) { vq_err(vq, "Failed to access avail idx at %p\n", &vq->avail->idx); return -EFAULT; @@ -2142,8 +2758,7 @@ 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(vhost_get_avail(vq, ring_head, - &vq->avail->ring[last_avail_idx & (vq->num - 1)]))) { + if (unlikely(vhost_get_avail_head(vq, &ring_head, last_avail_idx))) { vq_err(vq, "Failed to read head: idx %d address %p\n", last_avail_idx, &vq->avail->ring[last_avail_idx % vq->num]); @@ -2178,8 +2793,7 @@ int vhost_get_vq_desc(struct vhost_virtqueue *vq, i, vq->num, head); return -EINVAL; } - ret = vhost_copy_from_user(vq, &desc, vq->desc + i, - sizeof desc); + ret = vhost_get_desc(vq, &desc, i); if (unlikely(ret)) { vq_err(vq, "Failed to get descriptor: idx %d addr %p\n", i, vq->desc + i); @@ -2272,16 +2886,7 @@ 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 (vhost_put_user(vq, heads[0].id, &used->id)) { - vq_err(vq, "Failed to write used id"); - return -EFAULT; - } - if (vhost_put_user(vq, heads[0].len, &used->len)) { - vq_err(vq, "Failed to write used len"); - return -EFAULT; - } - } else if (vhost_copy_to_user(vq, used, heads, count * sizeof *used)) { + if (vhost_put_used(vq, heads, start, count)) { vq_err(vq, "Failed to write used"); return -EFAULT; } @@ -2323,8 +2928,7 @@ 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 (vhost_put_user(vq, cpu_to_vhost16(vq, vq->last_used_idx), - &vq->used->idx)) { + if (vhost_put_used_idx(vq)) { vq_err(vq, "Failed to increment used idx"); return -EFAULT; } @@ -2357,7 +2961,7 @@ 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 (vhost_get_avail(vq, flags, &vq->avail->flags)) { + if (vhost_get_avail_flags(vq, &flags)) { vq_err(vq, "Failed to get flags"); return true; } @@ -2371,7 +2975,7 @@ static bool vhost_notify(struct vhost_dev *dev, struct vhost_virtqueue *vq) if (unlikely(!v)) return true; - if (vhost_get_avail(vq, event, vhost_used_event(vq))) { + if (vhost_get_used_event(vq, &event)) { vq_err(vq, "Failed to get used event idx"); return true; } @@ -2416,7 +3020,7 @@ bool vhost_vq_avail_empty(struct vhost_dev *dev, struct vhost_virtqueue *vq) if (vq->avail_idx != vq->last_avail_idx) return false; - r = vhost_get_avail(vq, avail_idx, &vq->avail->idx); + r = vhost_get_avail_idx(vq, &avail_idx); if (unlikely(r)) return false; vq->avail_idx = vhost16_to_cpu(vq, avail_idx); @@ -2452,7 +3056,7 @@ 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 = vhost_get_avail(vq, avail_idx, &vq->avail->idx); + r = vhost_get_avail_idx(vq, &avail_idx); if (r) { vq_err(vq, "Failed to check avail idx at %p: %d\n", &vq->avail->idx, r); diff --git a/drivers/vhost/vhost.h b/drivers/vhost/vhost.h index 27a78a9b8cc7..819296332913 100644 --- a/drivers/vhost/vhost.h +++ b/drivers/vhost/vhost.h @@ -12,6 +12,9 @@ #include <linux/virtio_config.h> #include <linux/virtio_ring.h> #include <linux/atomic.h> +#include <linux/pagemap.h> +#include <linux/mmu_notifier.h> +#include <asm/cacheflush.h> struct vhost_work; typedef void (*vhost_work_fn_t)(struct vhost_work *work); @@ -80,6 +83,24 @@ enum vhost_uaddr_type { VHOST_NUM_ADDRS = 3, }; +struct vhost_map { + int npages; + void *addr; + struct page **pages; +}; + +struct vhost_uaddr { + unsigned long uaddr; + size_t size; + bool write; +}; + +#if defined(CONFIG_MMU_NOTIFIER) && ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE == 0 +#define VHOST_ARCH_CAN_ACCEL_UACCESS 1 +#else +#define VHOST_ARCH_CAN_ACCEL_UACCESS 0 +#endif + /* The virtqueue structure describes a queue attached to a device. */ struct vhost_virtqueue { struct vhost_dev *dev; @@ -90,7 +111,22 @@ struct vhost_virtqueue { struct vring_desc __user *desc; struct vring_avail __user *avail; struct vring_used __user *used; + +#if VHOST_ARCH_CAN_ACCEL_UACCESS + /* Read by memory accessors, modified by meta data + * prefetching, MMU notifier and vring ioctl(). + * Synchonrized through mmu_lock (writers) and RCU (writers + * and readers). + */ + struct vhost_map __rcu *maps[VHOST_NUM_ADDRS]; + /* Read by MMU notifier, modified by vring ioctl(), + * synchronized through MMU notifier + * registering/unregistering. + */ + struct vhost_uaddr uaddrs[VHOST_NUM_ADDRS]; +#endif const struct vhost_umem_node *meta_iotlb[VHOST_NUM_ADDRS]; + struct file *kick; struct eventfd_ctx *call_ctx; struct eventfd_ctx *error_ctx; @@ -145,6 +181,8 @@ struct vhost_virtqueue { bool user_be; #endif u32 busyloop_timeout; + spinlock_t mmu_lock; + int invalidate_count; }; struct vhost_msg_node { @@ -158,6 +196,9 @@ struct vhost_msg_node { struct vhost_dev { struct mm_struct *mm; +#ifdef CONFIG_MMU_NOTIFIER + struct mmu_notifier mmu_notifier; +#endif struct mutex mutex; struct vhost_virtqueue **vqs; int nvqs; @@ -212,7 +253,7 @@ 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, struct iovec *iov, int count); -int vq_iotlb_prefetch(struct vhost_virtqueue *vq); +int vq_meta_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, |