diff options
Diffstat (limited to 'arch/powerpc/kvm/book3s_64_vio.c')
| -rw-r--r-- | arch/powerpc/kvm/book3s_64_vio.c | 102 |
1 files changed, 81 insertions, 21 deletions
diff --git a/arch/powerpc/kvm/book3s_64_vio.c b/arch/powerpc/kvm/book3s_64_vio.c index f02b04973710..66270e07449a 100644 --- a/arch/powerpc/kvm/book3s_64_vio.c +++ b/arch/powerpc/kvm/book3s_64_vio.c @@ -228,11 +228,33 @@ static void release_spapr_tce_table(struct rcu_head *head) unsigned long i, npages = kvmppc_tce_pages(stt->size); for (i = 0; i < npages; i++) - __free_page(stt->pages[i]); + if (stt->pages[i]) + __free_page(stt->pages[i]); kfree(stt); } +static struct page *kvm_spapr_get_tce_page(struct kvmppc_spapr_tce_table *stt, + unsigned long sttpage) +{ + struct page *page = stt->pages[sttpage]; + + if (page) + return page; + + mutex_lock(&stt->alloc_lock); + page = stt->pages[sttpage]; + if (!page) { + page = alloc_page(GFP_KERNEL | __GFP_ZERO); + WARN_ON_ONCE(!page); + if (page) + stt->pages[sttpage] = page; + } + mutex_unlock(&stt->alloc_lock); + + return page; +} + static vm_fault_t kvm_spapr_tce_fault(struct vm_fault *vmf) { struct kvmppc_spapr_tce_table *stt = vmf->vma->vm_file->private_data; @@ -241,7 +263,10 @@ static vm_fault_t kvm_spapr_tce_fault(struct vm_fault *vmf) if (vmf->pgoff >= kvmppc_tce_pages(stt->size)) return VM_FAULT_SIGBUS; - page = stt->pages[vmf->pgoff]; + page = kvm_spapr_get_tce_page(stt, vmf->pgoff); + if (!page) + return VM_FAULT_OOM; + get_page(page); vmf->page = page; return 0; @@ -296,7 +321,6 @@ long kvm_vm_ioctl_create_spapr_tce(struct kvm *kvm, struct kvmppc_spapr_tce_table *siter; unsigned long npages, size = args->size; int ret = -ENOMEM; - int i; if (!args->size || args->page_shift < 12 || args->page_shift > 34 || (args->offset + args->size > (ULLONG_MAX >> args->page_shift))) @@ -318,14 +342,9 @@ long kvm_vm_ioctl_create_spapr_tce(struct kvm *kvm, stt->offset = args->offset; stt->size = size; stt->kvm = kvm; + mutex_init(&stt->alloc_lock); INIT_LIST_HEAD_RCU(&stt->iommu_tables); - for (i = 0; i < npages; i++) { - stt->pages[i] = alloc_page(GFP_KERNEL | __GFP_ZERO); - if (!stt->pages[i]) - goto fail; - } - mutex_lock(&kvm->lock); /* Check this LIOBN hasn't been previously allocated */ @@ -352,17 +371,28 @@ long kvm_vm_ioctl_create_spapr_tce(struct kvm *kvm, if (ret >= 0) return ret; - fail: - for (i = 0; i < npages; i++) - if (stt->pages[i]) - __free_page(stt->pages[i]); - kfree(stt); fail_acct: kvmppc_account_memlimit(kvmppc_stt_pages(npages), false); return ret; } +static long kvmppc_tce_to_ua(struct kvm *kvm, unsigned long tce, + unsigned long *ua) +{ + unsigned long gfn = tce >> PAGE_SHIFT; + struct kvm_memory_slot *memslot; + + memslot = search_memslots(kvm_memslots(kvm), gfn); + if (!memslot) + return -EINVAL; + + *ua = __gfn_to_hva_memslot(memslot, gfn) | + (tce & ~(PAGE_MASK | TCE_PCI_READ | TCE_PCI_WRITE)); + + return 0; +} + static long kvmppc_tce_validate(struct kvmppc_spapr_tce_table *stt, unsigned long tce) { @@ -378,7 +408,7 @@ static long kvmppc_tce_validate(struct kvmppc_spapr_tce_table *stt, if (iommu_tce_check_gpa(stt->page_shift, gpa)) return H_TOO_HARD; - if (kvmppc_tce_to_ua(stt->kvm, tce, &ua, NULL)) + if (kvmppc_tce_to_ua(stt->kvm, tce, &ua)) return H_TOO_HARD; list_for_each_entry_rcu(stit, &stt->iommu_tables, next) { @@ -397,6 +427,36 @@ static long kvmppc_tce_validate(struct kvmppc_spapr_tce_table *stt, return H_SUCCESS; } +/* + * Handles TCE requests for emulated devices. + * Puts guest TCE values to the table and expects user space to convert them. + * Cannot fail so kvmppc_tce_validate must be called before it. + */ +static void kvmppc_tce_put(struct kvmppc_spapr_tce_table *stt, + unsigned long idx, unsigned long tce) +{ + struct page *page; + u64 *tbl; + unsigned long sttpage; + + idx -= stt->offset; + sttpage = idx / TCES_PER_PAGE; + page = stt->pages[sttpage]; + + if (!page) { + /* We allow any TCE, not just with read|write permissions */ + if (!tce) + return; + + page = kvm_spapr_get_tce_page(stt, sttpage); + if (!page) + return; + } + tbl = page_to_virt(page); + + tbl[idx % TCES_PER_PAGE] = tce; +} + static void kvmppc_clear_tce(struct mm_struct *mm, struct iommu_table *tbl, unsigned long entry) { @@ -543,15 +603,15 @@ long kvmppc_h_put_tce(struct kvm_vcpu *vcpu, unsigned long liobn, if (ret != H_SUCCESS) return ret; + idx = srcu_read_lock(&vcpu->kvm->srcu); + ret = kvmppc_tce_validate(stt, tce); if (ret != H_SUCCESS) - return ret; + goto unlock_exit; dir = iommu_tce_direction(tce); - idx = srcu_read_lock(&vcpu->kvm->srcu); - - if ((dir != DMA_NONE) && kvmppc_tce_to_ua(vcpu->kvm, tce, &ua, NULL)) { + if ((dir != DMA_NONE) && kvmppc_tce_to_ua(vcpu->kvm, tce, &ua)) { ret = H_PARAMETER; goto unlock_exit; } @@ -612,7 +672,7 @@ long kvmppc_h_put_tce_indirect(struct kvm_vcpu *vcpu, return ret; idx = srcu_read_lock(&vcpu->kvm->srcu); - if (kvmppc_tce_to_ua(vcpu->kvm, tce_list, &ua, NULL)) { + if (kvmppc_tce_to_ua(vcpu->kvm, tce_list, &ua)) { ret = H_TOO_HARD; goto unlock_exit; } @@ -647,7 +707,7 @@ long kvmppc_h_put_tce_indirect(struct kvm_vcpu *vcpu, } tce = be64_to_cpu(tce); - if (kvmppc_tce_to_ua(vcpu->kvm, tce, &ua, NULL)) + if (kvmppc_tce_to_ua(vcpu->kvm, tce, &ua)) return H_PARAMETER; list_for_each_entry_lockless(stit, &stt->iommu_tables, next) { |