diff options
Diffstat (limited to 'drivers/vfio/vfio_iommu_type1.c')
| -rw-r--r-- | drivers/vfio/vfio_iommu_type1.c | 110 |
1 files changed, 101 insertions, 9 deletions
diff --git a/drivers/vfio/vfio_iommu_type1.c b/drivers/vfio/vfio_iommu_type1.c index 6cc47af1f06d..3b31e83a9215 100644 --- a/drivers/vfio/vfio_iommu_type1.c +++ b/drivers/vfio/vfio_iommu_type1.c @@ -335,6 +335,32 @@ static int put_pfn(unsigned long pfn, int prot) return 0; } +static int follow_fault_pfn(struct vm_area_struct *vma, struct mm_struct *mm, + unsigned long vaddr, unsigned long *pfn, + bool write_fault) +{ + int ret; + + ret = follow_pfn(vma, vaddr, pfn); + if (ret) { + bool unlocked = false; + + ret = fixup_user_fault(NULL, mm, vaddr, + FAULT_FLAG_REMOTE | + (write_fault ? FAULT_FLAG_WRITE : 0), + &unlocked); + if (unlocked) + return -EAGAIN; + + if (ret) + return ret; + + ret = follow_pfn(vma, vaddr, pfn); + } + + return ret; +} + static int vaddr_get_pfn(struct mm_struct *mm, unsigned long vaddr, int prot, unsigned long *pfn) { @@ -377,12 +403,16 @@ static int vaddr_get_pfn(struct mm_struct *mm, unsigned long vaddr, vaddr = untagged_addr(vaddr); +retry: vma = find_vma_intersection(mm, vaddr, vaddr + 1); if (vma && vma->vm_flags & VM_PFNMAP) { - if (!follow_pfn(vma, vaddr, pfn) && - is_invalid_reserved_pfn(*pfn)) - ret = 0; + ret = follow_fault_pfn(vma, mm, vaddr, pfn, prot & IOMMU_WRITE); + if (ret == -EAGAIN) + goto retry; + + if (!ret && !is_invalid_reserved_pfn(*pfn)) + ret = -EFAULT; } up_read(&mm->mmap_sem); @@ -601,7 +631,8 @@ static int vfio_iommu_type1_pin_pages(void *iommu_data, ret = vfio_add_to_pfn_list(dma, iova, phys_pfn[i]); if (ret) { - vfio_unpin_page_external(dma, iova, do_accounting); + if (put_pfn(phys_pfn[i], dma->prot) && do_accounting) + vfio_lock_acct(dma, -1, true); goto pin_unwind; } } @@ -1187,13 +1218,16 @@ static int vfio_bus_type(struct device *dev, void *data) static int vfio_iommu_replay(struct vfio_iommu *iommu, struct vfio_domain *domain) { - struct vfio_domain *d; + struct vfio_domain *d = NULL; struct rb_node *n; unsigned long limit = rlimit(RLIMIT_MEMLOCK) >> PAGE_SHIFT; int ret; /* Arbitrarily pick the first domain in the list for lookups */ - d = list_first_entry(&iommu->domain_list, struct vfio_domain, next); + if (!list_empty(&iommu->domain_list)) + d = list_first_entry(&iommu->domain_list, + struct vfio_domain, next); + n = rb_first(&iommu->dma_list); for (; n; n = rb_next(n)) { @@ -1211,6 +1245,11 @@ static int vfio_iommu_replay(struct vfio_iommu *iommu, phys_addr_t p; dma_addr_t i; + if (WARN_ON(!d)) { /* mapped w/o a domain?! */ + ret = -EINVAL; + goto unwind; + } + phys = iommu_iova_to_phys(d->domain, iova); if (WARN_ON(!phys)) { @@ -1240,7 +1279,7 @@ static int vfio_iommu_replay(struct vfio_iommu *iommu, if (npage <= 0) { WARN_ON(!npage); ret = (int)npage; - return ret; + goto unwind; } phys = pfn << PAGE_SHIFT; @@ -1249,14 +1288,67 @@ static int vfio_iommu_replay(struct vfio_iommu *iommu, ret = iommu_map(domain->domain, iova, phys, size, dma->prot | domain->prot); - if (ret) - return ret; + if (ret) { + if (!dma->iommu_mapped) + vfio_unpin_pages_remote(dma, iova, + phys >> PAGE_SHIFT, + size >> PAGE_SHIFT, + true); + goto unwind; + } iova += size; } + } + + /* All dmas are now mapped, defer to second tree walk for unwind */ + for (n = rb_first(&iommu->dma_list); n; n = rb_next(n)) { + struct vfio_dma *dma = rb_entry(n, struct vfio_dma, node); + dma->iommu_mapped = true; } + return 0; + +unwind: + for (; n; n = rb_prev(n)) { + struct vfio_dma *dma = rb_entry(n, struct vfio_dma, node); + dma_addr_t iova; + + if (dma->iommu_mapped) { + iommu_unmap(domain->domain, dma->iova, dma->size); + continue; + } + + iova = dma->iova; + while (iova < dma->iova + dma->size) { + phys_addr_t phys, p; + size_t size; + dma_addr_t i; + + phys = iommu_iova_to_phys(domain->domain, iova); + if (!phys) { + iova += PAGE_SIZE; + continue; + } + + size = PAGE_SIZE; + p = phys + size; + i = iova + size; + while (i < dma->iova + dma->size && + p == iommu_iova_to_phys(domain->domain, i)) { + size += PAGE_SIZE; + p += PAGE_SIZE; + i += PAGE_SIZE; + } + + iommu_unmap(domain->domain, iova, size); + vfio_unpin_pages_remote(dma, iova, phys >> PAGE_SHIFT, + size >> PAGE_SHIFT, true); + } + } + + return ret; } /* |