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author | Alex Williamson <alex.williamson@redhat.com> | 2021-02-02 19:17:48 +0300 |
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committer | Alex Williamson <alex.williamson@redhat.com> | 2021-02-02 19:17:48 +0300 |
commit | 76adb20f924f8d27ed50d02cd29cadedb59fd88f (patch) | |
tree | 90838d7747333619c7836252b37147b104d5b689 /drivers/vfio/vfio_iommu_type1.c | |
parent | 7e31d6dc2c78b2a0ba0039ca97ca98a581e8db82 (diff) | |
parent | 898b9eaeb3fe5eb1ac510f2c4775c8277206752c (diff) | |
download | linux-76adb20f924f8d27ed50d02cd29cadedb59fd88f.tar.xz |
Merge branch 'v5.12/vfio/next-vaddr' into v5.12/vfio/next
Diffstat (limited to 'drivers/vfio/vfio_iommu_type1.c')
-rw-r--r-- | drivers/vfio/vfio_iommu_type1.c | 249 |
1 files changed, 217 insertions, 32 deletions
diff --git a/drivers/vfio/vfio_iommu_type1.c b/drivers/vfio/vfio_iommu_type1.c index 706b88b5d4ee..ec9fd95a138b 100644 --- a/drivers/vfio/vfio_iommu_type1.c +++ b/drivers/vfio/vfio_iommu_type1.c @@ -31,6 +31,7 @@ #include <linux/rbtree.h> #include <linux/sched/signal.h> #include <linux/sched/mm.h> +#include <linux/kthread.h> #include <linux/slab.h> #include <linux/uaccess.h> #include <linux/vfio.h> @@ -69,11 +70,15 @@ struct vfio_iommu { struct rb_root dma_list; struct blocking_notifier_head notifier; unsigned int dma_avail; + unsigned int vaddr_invalid_count; uint64_t pgsize_bitmap; uint64_t num_non_pinned_groups; + wait_queue_head_t vaddr_wait; bool v2; bool nesting; bool dirty_page_tracking; + bool pinned_page_dirty_scope; + bool container_open; }; struct vfio_domain { @@ -92,6 +97,7 @@ struct vfio_dma { int prot; /* IOMMU_READ/WRITE */ bool iommu_mapped; bool lock_cap; /* capable(CAP_IPC_LOCK) */ + bool vaddr_invalid; struct task_struct *task; struct rb_root pfn_list; /* Ex-user pinned pfn list */ unsigned long *bitmap; @@ -143,6 +149,8 @@ struct vfio_regions { #define DIRTY_BITMAP_PAGES_MAX ((u64)INT_MAX) #define DIRTY_BITMAP_SIZE_MAX DIRTY_BITMAP_BYTES(DIRTY_BITMAP_PAGES_MAX) +#define WAITED 1 + static int put_pfn(unsigned long pfn, int prot); static struct vfio_group *vfio_iommu_find_iommu_group(struct vfio_iommu *iommu, @@ -172,6 +180,31 @@ static struct vfio_dma *vfio_find_dma(struct vfio_iommu *iommu, return NULL; } +static struct rb_node *vfio_find_dma_first_node(struct vfio_iommu *iommu, + dma_addr_t start, size_t size) +{ + struct rb_node *res = NULL; + struct rb_node *node = iommu->dma_list.rb_node; + struct vfio_dma *dma_res = NULL; + + while (node) { + struct vfio_dma *dma = rb_entry(node, struct vfio_dma, node); + + if (start < dma->iova + dma->size) { + res = node; + dma_res = dma; + if (start >= dma->iova) + break; + node = node->rb_left; + } else { + node = node->rb_right; + } + } + if (res && size && dma_res->iova >= start + size) + res = NULL; + return res; +} + static void vfio_link_dma(struct vfio_iommu *iommu, struct vfio_dma *new) { struct rb_node **link = &iommu->dma_list.rb_node, *parent = NULL; @@ -490,6 +523,61 @@ done: return ret; } +static int vfio_wait(struct vfio_iommu *iommu) +{ + DEFINE_WAIT(wait); + + prepare_to_wait(&iommu->vaddr_wait, &wait, TASK_KILLABLE); + mutex_unlock(&iommu->lock); + schedule(); + mutex_lock(&iommu->lock); + finish_wait(&iommu->vaddr_wait, &wait); + if (kthread_should_stop() || !iommu->container_open || + fatal_signal_pending(current)) { + return -EFAULT; + } + return WAITED; +} + +/* + * Find dma struct and wait for its vaddr to be valid. iommu lock is dropped + * if the task waits, but is re-locked on return. Return result in *dma_p. + * Return 0 on success with no waiting, WAITED on success if waited, and -errno + * on error. + */ +static int vfio_find_dma_valid(struct vfio_iommu *iommu, dma_addr_t start, + size_t size, struct vfio_dma **dma_p) +{ + int ret; + + do { + *dma_p = vfio_find_dma(iommu, start, size); + if (!*dma_p) + ret = -EINVAL; + else if (!(*dma_p)->vaddr_invalid) + ret = 0; + else + ret = vfio_wait(iommu); + } while (ret > 0); + + return ret; +} + +/* + * Wait for all vaddr in the dma_list to become valid. iommu lock is dropped + * if the task waits, but is re-locked on return. Return 0 on success with no + * waiting, WAITED on success if waited, and -errno on error. + */ +static int vfio_wait_all_valid(struct vfio_iommu *iommu) +{ + int ret = 0; + + while (iommu->vaddr_invalid_count && ret >= 0) + ret = vfio_wait(iommu); + + return ret; +} + /* * Attempt to pin pages. We really don't want to track all the pfns and * the iommu can only map chunks of consecutive pfns anyway, so get the @@ -651,6 +739,7 @@ static int vfio_iommu_type1_pin_pages(void *iommu_data, unsigned long remote_vaddr; struct vfio_dma *dma; bool do_accounting; + dma_addr_t iova; if (!iommu || !user_pfn || !phys_pfn) return -EINVAL; @@ -661,6 +750,22 @@ static int vfio_iommu_type1_pin_pages(void *iommu_data, mutex_lock(&iommu->lock); + /* + * Wait for all necessary vaddr's to be valid so they can be used in + * the main loop without dropping the lock, to avoid racing vs unmap. + */ +again: + if (iommu->vaddr_invalid_count) { + for (i = 0; i < npage; i++) { + iova = user_pfn[i] << PAGE_SHIFT; + ret = vfio_find_dma_valid(iommu, iova, PAGE_SIZE, &dma); + if (ret < 0) + goto pin_done; + if (ret == WAITED) + goto again; + } + } + /* Fail if notifier list is empty */ if (!iommu->notifier.head) { ret = -EINVAL; @@ -675,7 +780,6 @@ static int vfio_iommu_type1_pin_pages(void *iommu_data, do_accounting = !IS_IOMMU_CAP_DOMAIN_IN_CONTAINER(iommu); for (i = 0; i < npage; i++) { - dma_addr_t iova; struct vfio_pfn *vpfn; iova = user_pfn[i] << PAGE_SHIFT; @@ -961,6 +1065,10 @@ static void vfio_remove_dma(struct vfio_iommu *iommu, struct vfio_dma *dma) vfio_unlink_dma(iommu, dma); put_task_struct(dma->task); vfio_dma_bitmap_free(dma); + if (dma->vaddr_invalid) { + iommu->vaddr_invalid_count--; + wake_up_all(&iommu->vaddr_wait); + } kfree(dma); iommu->dma_avail++; } @@ -1086,34 +1194,36 @@ static int vfio_dma_do_unmap(struct vfio_iommu *iommu, { struct vfio_dma *dma, *dma_last = NULL; size_t unmapped = 0, pgsize; - int ret = 0, retries = 0; + int ret = -EINVAL, retries = 0; unsigned long pgshift; + dma_addr_t iova = unmap->iova; + unsigned long size = unmap->size; + bool unmap_all = unmap->flags & VFIO_DMA_UNMAP_FLAG_ALL; + bool invalidate_vaddr = unmap->flags & VFIO_DMA_UNMAP_FLAG_VADDR; + struct rb_node *n, *first_n; mutex_lock(&iommu->lock); pgshift = __ffs(iommu->pgsize_bitmap); pgsize = (size_t)1 << pgshift; - if (unmap->iova & (pgsize - 1)) { - ret = -EINVAL; + if (iova & (pgsize - 1)) goto unlock; - } - if (!unmap->size || unmap->size & (pgsize - 1)) { - ret = -EINVAL; + if (unmap_all) { + if (iova || size) + goto unlock; + size = SIZE_MAX; + } else if (!size || size & (pgsize - 1)) { goto unlock; } - if (unmap->iova + unmap->size - 1 < unmap->iova || - unmap->size > SIZE_MAX) { - ret = -EINVAL; + if (iova + size - 1 < iova || size > SIZE_MAX) goto unlock; - } /* When dirty tracking is enabled, allow only min supported pgsize */ if ((unmap->flags & VFIO_DMA_UNMAP_FLAG_GET_DIRTY_BITMAP) && (!iommu->dirty_page_tracking || (bitmap->pgsize != pgsize))) { - ret = -EINVAL; goto unlock; } @@ -1150,21 +1260,25 @@ again: * will only return success and a size of zero if there were no * mappings within the range. */ - if (iommu->v2) { - dma = vfio_find_dma(iommu, unmap->iova, 1); - if (dma && dma->iova != unmap->iova) { - ret = -EINVAL; + if (iommu->v2 && !unmap_all) { + dma = vfio_find_dma(iommu, iova, 1); + if (dma && dma->iova != iova) goto unlock; - } - dma = vfio_find_dma(iommu, unmap->iova + unmap->size - 1, 0); - if (dma && dma->iova + dma->size != unmap->iova + unmap->size) { - ret = -EINVAL; + + dma = vfio_find_dma(iommu, iova + size - 1, 0); + if (dma && dma->iova + dma->size != iova + size) goto unlock; - } } - while ((dma = vfio_find_dma(iommu, unmap->iova, unmap->size))) { - if (!iommu->v2 && unmap->iova > dma->iova) + ret = 0; + n = first_n = vfio_find_dma_first_node(iommu, iova, size); + + while (n) { + dma = rb_entry(n, struct vfio_dma, node); + if (dma->iova >= iova + size) + break; + + if (!iommu->v2 && iova > dma->iova) break; /* * Task with same address space who mapped this iova range is @@ -1173,6 +1287,27 @@ again: if (dma->task->mm != current->mm) break; + if (invalidate_vaddr) { + if (dma->vaddr_invalid) { + struct rb_node *last_n = n; + + for (n = first_n; n != last_n; n = rb_next(n)) { + dma = rb_entry(n, + struct vfio_dma, node); + dma->vaddr_invalid = false; + iommu->vaddr_invalid_count--; + } + ret = -EINVAL; + unmapped = 0; + break; + } + dma->vaddr_invalid = true; + iommu->vaddr_invalid_count++; + unmapped += dma->size; + n = rb_next(n); + continue; + } + if (!RB_EMPTY_ROOT(&dma->pfn_list)) { struct vfio_iommu_type1_dma_unmap nb_unmap; @@ -1202,12 +1337,13 @@ again: if (unmap->flags & VFIO_DMA_UNMAP_FLAG_GET_DIRTY_BITMAP) { ret = update_user_bitmap(bitmap->data, iommu, dma, - unmap->iova, pgsize); + iova, pgsize); if (ret) break; } unmapped += dma->size; + n = rb_next(n); vfio_remove_dma(iommu, dma); } @@ -1311,6 +1447,7 @@ static bool vfio_iommu_iova_dma_valid(struct vfio_iommu *iommu, static int vfio_dma_do_map(struct vfio_iommu *iommu, struct vfio_iommu_type1_dma_map *map) { + bool set_vaddr = map->flags & VFIO_DMA_MAP_FLAG_VADDR; dma_addr_t iova = map->iova; unsigned long vaddr = map->vaddr; size_t size = map->size; @@ -1328,13 +1465,16 @@ static int vfio_dma_do_map(struct vfio_iommu *iommu, if (map->flags & VFIO_DMA_MAP_FLAG_READ) prot |= IOMMU_READ; + if ((prot && set_vaddr) || (!prot && !set_vaddr)) + return -EINVAL; + mutex_lock(&iommu->lock); pgsize = (size_t)1 << __ffs(iommu->pgsize_bitmap); WARN_ON((pgsize - 1) & PAGE_MASK); - if (!prot || !size || (size | iova | vaddr) & (pgsize - 1)) { + if (!size || (size | iova | vaddr) & (pgsize - 1)) { ret = -EINVAL; goto out_unlock; } @@ -1345,7 +1485,21 @@ static int vfio_dma_do_map(struct vfio_iommu *iommu, goto out_unlock; } - if (vfio_find_dma(iommu, iova, size)) { + dma = vfio_find_dma(iommu, iova, size); + if (set_vaddr) { + if (!dma) { + ret = -ENOENT; + } else if (!dma->vaddr_invalid || dma->iova != iova || + dma->size != size) { + ret = -EINVAL; + } else { + dma->vaddr = vaddr; + dma->vaddr_invalid = false; + iommu->vaddr_invalid_count--; + wake_up_all(&iommu->vaddr_wait); + } + goto out_unlock; + } else if (dma) { ret = -EEXIST; goto out_unlock; } @@ -1442,6 +1596,10 @@ static int vfio_iommu_replay(struct vfio_iommu *iommu, unsigned long limit = rlimit(RLIMIT_MEMLOCK) >> PAGE_SHIFT; int ret; + ret = vfio_wait_all_valid(iommu); + if (ret < 0) + return ret; + /* Arbitrarily pick the first domain in the list for lookups */ if (!list_empty(&iommu->domain_list)) d = list_first_entry(&iommu->domain_list, @@ -2417,8 +2575,10 @@ static void *vfio_iommu_type1_open(unsigned long arg) INIT_LIST_HEAD(&iommu->iova_list); iommu->dma_list = RB_ROOT; iommu->dma_avail = dma_entry_limit; + iommu->container_open = true; mutex_init(&iommu->lock); BLOCKING_INIT_NOTIFIER_HEAD(&iommu->notifier); + init_waitqueue_head(&iommu->vaddr_wait); return iommu; } @@ -2487,6 +2647,8 @@ static int vfio_iommu_type1_check_extension(struct vfio_iommu *iommu, case VFIO_TYPE1_IOMMU: case VFIO_TYPE1v2_IOMMU: case VFIO_TYPE1_NESTING_IOMMU: + case VFIO_UNMAP_ALL: + case VFIO_UPDATE_VADDR: return 1; case VFIO_DMA_CC_IOMMU: if (!iommu) @@ -2658,7 +2820,8 @@ static int vfio_iommu_type1_map_dma(struct vfio_iommu *iommu, { struct vfio_iommu_type1_dma_map map; unsigned long minsz; - uint32_t mask = VFIO_DMA_MAP_FLAG_READ | VFIO_DMA_MAP_FLAG_WRITE; + uint32_t mask = VFIO_DMA_MAP_FLAG_READ | VFIO_DMA_MAP_FLAG_WRITE | + VFIO_DMA_MAP_FLAG_VADDR; minsz = offsetofend(struct vfio_iommu_type1_dma_map, size); @@ -2676,6 +2839,9 @@ static int vfio_iommu_type1_unmap_dma(struct vfio_iommu *iommu, { struct vfio_iommu_type1_dma_unmap unmap; struct vfio_bitmap bitmap = { 0 }; + uint32_t mask = VFIO_DMA_UNMAP_FLAG_GET_DIRTY_BITMAP | + VFIO_DMA_UNMAP_FLAG_VADDR | + VFIO_DMA_UNMAP_FLAG_ALL; unsigned long minsz; int ret; @@ -2684,8 +2850,12 @@ static int vfio_iommu_type1_unmap_dma(struct vfio_iommu *iommu, if (copy_from_user(&unmap, (void __user *)arg, minsz)) return -EFAULT; - if (unmap.argsz < minsz || - unmap.flags & ~VFIO_DMA_UNMAP_FLAG_GET_DIRTY_BITMAP) + if (unmap.argsz < minsz || unmap.flags & ~mask) + return -EINVAL; + + if ((unmap.flags & VFIO_DMA_UNMAP_FLAG_GET_DIRTY_BITMAP) && + (unmap.flags & (VFIO_DMA_UNMAP_FLAG_ALL | + VFIO_DMA_UNMAP_FLAG_VADDR))) return -EINVAL; if (unmap.flags & VFIO_DMA_UNMAP_FLAG_GET_DIRTY_BITMAP) { @@ -2876,12 +3046,13 @@ static int vfio_iommu_type1_dma_rw_chunk(struct vfio_iommu *iommu, struct vfio_dma *dma; bool kthread = current->mm == NULL; size_t offset; + int ret; *copied = 0; - dma = vfio_find_dma(iommu, user_iova, 1); - if (!dma) - return -EINVAL; + ret = vfio_find_dma_valid(iommu, user_iova, 1, &dma); + if (ret < 0) + return ret; if ((write && !(dma->prot & IOMMU_WRITE)) || !(dma->prot & IOMMU_READ)) @@ -2973,6 +3144,19 @@ vfio_iommu_type1_group_iommu_domain(void *iommu_data, return domain; } +static void vfio_iommu_type1_notify(void *iommu_data, + enum vfio_iommu_notify_type event) +{ + struct vfio_iommu *iommu = iommu_data; + + if (event != VFIO_IOMMU_CONTAINER_CLOSE) + return; + mutex_lock(&iommu->lock); + iommu->container_open = false; + mutex_unlock(&iommu->lock); + wake_up_all(&iommu->vaddr_wait); +} + static const struct vfio_iommu_driver_ops vfio_iommu_driver_ops_type1 = { .name = "vfio-iommu-type1", .owner = THIS_MODULE, @@ -2987,6 +3171,7 @@ static const struct vfio_iommu_driver_ops vfio_iommu_driver_ops_type1 = { .unregister_notifier = vfio_iommu_type1_unregister_notifier, .dma_rw = vfio_iommu_type1_dma_rw, .group_iommu_domain = vfio_iommu_type1_group_iommu_domain, + .notify = vfio_iommu_type1_notify, }; static int __init vfio_iommu_type1_init(void) |