phys_addr_t addr = start, end = start + size;
phys_addr_t next;
- pgd = pgdp + pgd_index(addr);
+ pgd = pgdp + kvm_pgd_index(addr);
do {
next = kvm_pgd_addr_end(addr, end);
if (!pgd_none(*pgd))
phys_addr_t next;
pgd_t *pgd;
- pgd = kvm->arch.pgd + pgd_index(addr);
+ pgd = kvm->arch.pgd + kvm_pgd_index(addr);
do {
next = kvm_pgd_addr_end(addr, end);
stage2_flush_puds(kvm, pgd, addr, next);
__phys_to_pfn(phys_addr), PAGE_HYP_DEVICE);
}
+/* Free the HW pgd, one page at a time */
+static void kvm_free_hwpgd(void *hwpgd)
+{
+ free_pages_exact(hwpgd, kvm_get_hwpgd_size());
+}
+
+/* Allocate the HW PGD, making sure that each page gets its own refcount */
+static void *kvm_alloc_hwpgd(void)
+{
+ unsigned int size = kvm_get_hwpgd_size();
+
+ return alloc_pages_exact(size, GFP_KERNEL | __GFP_ZERO);
+}
+
/**
* kvm_alloc_stage2_pgd - allocate level-1 table for stage-2 translation.
* @kvm: The KVM struct pointer for the VM.
*/
int kvm_alloc_stage2_pgd(struct kvm *kvm)
{
- int ret;
pgd_t *pgd;
+ void *hwpgd;
if (kvm->arch.pgd != NULL) {
kvm_err("kvm_arch already initialized?\n");
return -EINVAL;
}
+ hwpgd = kvm_alloc_hwpgd();
+ if (!hwpgd)
+ return -ENOMEM;
+
+ /* When the kernel uses more levels of page tables than the
+ * guest, we allocate a fake PGD and pre-populate it to point
+ * to the next-level page table, which will be the real
+ * initial page table pointed to by the VTTBR.
+ *
+ * When KVM_PREALLOC_LEVEL==2, we allocate a single page for
+ * the PMD and the kernel will use folded pud.
+ * When KVM_PREALLOC_LEVEL==1, we allocate 2 consecutive PUD
+ * pages.
+ */
if (KVM_PREALLOC_LEVEL > 0) {
+ int i;
+
/*
* Allocate fake pgd for the page table manipulation macros to
* work. This is not used by the hardware and we have no
*/
pgd = (pgd_t *)kmalloc(PTRS_PER_S2_PGD * sizeof(pgd_t),
GFP_KERNEL | __GFP_ZERO);
+
+ if (!pgd) {
+ kvm_free_hwpgd(hwpgd);
+ return -ENOMEM;
+ }
+
+ /* Plug the HW PGD into the fake one. */
+ for (i = 0; i < PTRS_PER_S2_PGD; i++) {
+ if (KVM_PREALLOC_LEVEL == 1)
+ pgd_populate(NULL, pgd + i,
+ (pud_t *)hwpgd + i * PTRS_PER_PUD);
+ else if (KVM_PREALLOC_LEVEL == 2)
+ pud_populate(NULL, pud_offset(pgd, 0) + i,
+ (pmd_t *)hwpgd + i * PTRS_PER_PMD);
+ }
} else {
/*
* Allocate actual first-level Stage-2 page table used by the
* hardware for Stage-2 page table walks.
*/
- pgd = (pgd_t *)__get_free_pages(GFP_KERNEL | __GFP_ZERO, S2_PGD_ORDER);
+ pgd = (pgd_t *)hwpgd;
}
- if (!pgd)
- return -ENOMEM;
-
- ret = kvm_prealloc_hwpgd(kvm, pgd);
- if (ret)
- goto out_err;
-
kvm_clean_pgd(pgd);
kvm->arch.pgd = pgd;
return 0;
-out_err:
- if (KVM_PREALLOC_LEVEL > 0)
- kfree(pgd);
- else
- free_pages((unsigned long)pgd, S2_PGD_ORDER);
- return ret;
}
/**
return;
unmap_stage2_range(kvm, 0, KVM_PHYS_SIZE);
- kvm_free_hwpgd(kvm);
+ kvm_free_hwpgd(kvm_get_hwpgd(kvm));
if (KVM_PREALLOC_LEVEL > 0)
kfree(kvm->arch.pgd);
- else
- free_pages((unsigned long)kvm->arch.pgd, S2_PGD_ORDER);
+
kvm->arch.pgd = NULL;
}
pgd_t *pgd;
pud_t *pud;
- pgd = kvm->arch.pgd + pgd_index(addr);
+ pgd = kvm->arch.pgd + kvm_pgd_index(addr);
if (WARN_ON(pgd_none(*pgd))) {
if (!cache)
return NULL;
pgd_t *pgd;
phys_addr_t next;
- pgd = kvm->arch.pgd + pgd_index(addr);
+ pgd = kvm->arch.pgd + kvm_pgd_index(addr);
do {
/*
* Release kvm_mmu_lock periodically if the memory region is
return ret;
}
+/*
+ * Resolve the access fault by making the page young again.
+ * Note that because the faulting entry is guaranteed not to be
+ * cached in the TLB, we don't need to invalidate anything.
+ */
+static void handle_access_fault(struct kvm_vcpu *vcpu, phys_addr_t fault_ipa)
+{
+ pmd_t *pmd;
+ pte_t *pte;
+ pfn_t pfn;
+ bool pfn_valid = false;
+
+ trace_kvm_access_fault(fault_ipa);
+
+ spin_lock(&vcpu->kvm->mmu_lock);
+
+ pmd = stage2_get_pmd(vcpu->kvm, NULL, fault_ipa);
+ if (!pmd || pmd_none(*pmd)) /* Nothing there */
+ goto out;
+
+ if (kvm_pmd_huge(*pmd)) { /* THP, HugeTLB */
+ *pmd = pmd_mkyoung(*pmd);
+ pfn = pmd_pfn(*pmd);
+ pfn_valid = true;
+ goto out;
+ }
+
+ pte = pte_offset_kernel(pmd, fault_ipa);
+ if (pte_none(*pte)) /* Nothing there either */
+ goto out;
+
+ *pte = pte_mkyoung(*pte); /* Just a page... */
+ pfn = pte_pfn(*pte);
+ pfn_valid = true;
+out:
+ spin_unlock(&vcpu->kvm->mmu_lock);
+ if (pfn_valid)
+ kvm_set_pfn_accessed(pfn);
+}
+
/**
* kvm_handle_guest_abort - handles all 2nd stage aborts
* @vcpu: the VCPU pointer
/* Userspace should not be able to register out-of-bounds IPAs */
VM_BUG_ON(fault_ipa >= KVM_PHYS_SIZE);
+ if (fault_status == FSC_ACCESS) {
+ handle_access_fault(vcpu, fault_ipa);
+ ret = 1;
+ goto out_unlock;
+ }
+
ret = user_mem_abort(vcpu, fault_ipa, memslot, hva, fault_status);
if (ret == 0)
ret = 1;
git.samba.org / sfrench / cifs-2.6.git / blobdiff