bool kvm_is_mmio_pfn(pfn_t pfn)
{
- if (is_error_pfn(pfn))
- return false;
-
if (pfn_valid(pfn)) {
int reserved;
struct page *tail = pfn_to_page(pfn);
/*
* Switches to specified vcpu, until a matching vcpu_put()
*/
-void vcpu_load(struct kvm_vcpu *vcpu)
+int vcpu_load(struct kvm_vcpu *vcpu)
{
int cpu;
- mutex_lock(&vcpu->mutex);
+ if (mutex_lock_killable(&vcpu->mutex))
+ return -EINTR;
if (unlikely(vcpu->pid != current->pids[PIDTYPE_PID].pid)) {
/* The thread running this VCPU changed. */
struct pid *oldpid = vcpu->pid;
preempt_notifier_register(&vcpu->preempt_notifier);
kvm_arch_vcpu_load(vcpu, cpu);
put_cpu();
+ return 0;
}
void vcpu_put(struct kvm_vcpu *vcpu)
int idx;
idx = srcu_read_lock(&kvm->srcu);
- kvm_arch_flush_shadow(kvm);
+ kvm_arch_flush_shadow_all(kvm);
srcu_read_unlock(&kvm->srcu, idx);
}
#if defined(CONFIG_MMU_NOTIFIER) && defined(KVM_ARCH_WANT_MMU_NOTIFIER)
mmu_notifier_unregister(&kvm->mmu_notifier, kvm->mm);
#else
- kvm_arch_flush_shadow(kvm);
+ kvm_arch_flush_shadow_all(kvm);
#endif
kvm_arch_destroy_vm(kvm);
kvm_free_physmem(kvm);
slots->generation++;
}
+static int check_memory_region_flags(struct kvm_userspace_memory_region *mem)
+{
+ u32 valid_flags = KVM_MEM_LOG_DIRTY_PAGES;
+
+#ifdef KVM_CAP_READONLY_MEM
+ valid_flags |= KVM_MEM_READONLY;
+#endif
+
+ if (mem->flags & ~valid_flags)
+ return -EINVAL;
+
+ return 0;
+}
+
/*
* Allocate some memory and give it an address in the guest physical address
* space.
struct kvm_memory_slot old, new;
struct kvm_memslots *slots, *old_memslots;
+ r = check_memory_region_flags(mem);
+ if (r)
+ goto out;
+
r = -EINVAL;
/* General sanity checks */
if (mem->memory_size & (PAGE_SIZE - 1))
/* destroy any largepage mappings for dirty tracking */
}
- if (!npages) {
+ if (!npages || base_gfn != old.base_gfn) {
struct kvm_memory_slot *slot;
r = -ENOMEM;
old_memslots = kvm->memslots;
rcu_assign_pointer(kvm->memslots, slots);
synchronize_srcu_expedited(&kvm->srcu);
- /* From this point no new shadow pages pointing to a deleted
- * memslot will be created.
+ /* From this point no new shadow pages pointing to a deleted,
+ * or moved, memslot will be created.
*
* validation of sp->gfn happens in:
* - gfn_to_hva (kvm_read_guest, gfn_to_pfn)
* - kvm_is_visible_gfn (mmu_check_roots)
*/
- kvm_arch_flush_shadow(kvm);
+ kvm_arch_flush_shadow_memslot(kvm, slot);
kfree(old_memslots);
}
kvm_arch_commit_memory_region(kvm, mem, old, user_alloc);
- /*
- * If the new memory slot is created, we need to clear all
- * mmio sptes.
- */
- if (npages && old.base_gfn != mem->guest_phys_addr >> PAGE_SHIFT)
- kvm_arch_flush_shadow(kvm);
-
kvm_free_physmem_slot(&old, &new);
kfree(old_memslots);
}
EXPORT_SYMBOL_GPL(kvm_disable_largepages);
-int is_error_page(struct page *page)
-{
- return IS_ERR(page);
-}
-EXPORT_SYMBOL_GPL(is_error_page);
-
-struct page *get_bad_page(void)
-{
- return ERR_PTR(-ENOENT);
-}
-
-static inline unsigned long bad_hva(void)
-{
- return PAGE_OFFSET;
-}
-
-int kvm_is_error_hva(unsigned long addr)
-{
- return addr == bad_hva();
-}
-EXPORT_SYMBOL_GPL(kvm_is_error_hva);
-
struct kvm_memory_slot *gfn_to_memslot(struct kvm *kvm, gfn_t gfn)
{
return __gfn_to_memslot(kvm_memslots(kvm), gfn);
return size;
}
-static unsigned long gfn_to_hva_many(struct kvm_memory_slot *slot, gfn_t gfn,
- gfn_t *nr_pages)
+static bool memslot_is_readonly(struct kvm_memory_slot *slot)
+{
+ return slot->flags & KVM_MEM_READONLY;
+}
+
+static unsigned long __gfn_to_hva_many(struct kvm_memory_slot *slot, gfn_t gfn,
+ gfn_t *nr_pages, bool write)
{
if (!slot || slot->flags & KVM_MEMSLOT_INVALID)
- return bad_hva();
+ return KVM_HVA_ERR_BAD;
+
+ if (memslot_is_readonly(slot) && write)
+ return KVM_HVA_ERR_RO_BAD;
if (nr_pages)
*nr_pages = slot->npages - (gfn - slot->base_gfn);
- return gfn_to_hva_memslot(slot, gfn);
+ return __gfn_to_hva_memslot(slot, gfn);
+}
+
+static unsigned long gfn_to_hva_many(struct kvm_memory_slot *slot, gfn_t gfn,
+ gfn_t *nr_pages)
+{
+ return __gfn_to_hva_many(slot, gfn, nr_pages, true);
+}
+
+unsigned long gfn_to_hva_memslot(struct kvm_memory_slot *slot,
+ gfn_t gfn)
+{
+ return gfn_to_hva_many(slot, gfn, NULL);
}
+EXPORT_SYMBOL_GPL(gfn_to_hva_memslot);
unsigned long gfn_to_hva(struct kvm *kvm, gfn_t gfn)
{
}
EXPORT_SYMBOL_GPL(gfn_to_hva);
+/*
+ * The hva returned by this function is only allowed to be read.
+ * It should pair with kvm_read_hva() or kvm_read_hva_atomic().
+ */
+static unsigned long gfn_to_hva_read(struct kvm *kvm, gfn_t gfn)
+{
+ return __gfn_to_hva_many(gfn_to_memslot(kvm, gfn), gfn, NULL, false);
+}
+
+static int kvm_read_hva(void *data, void __user *hva, int len)
+{
+ return __copy_from_user(data, hva, len);
+}
+
+static int kvm_read_hva_atomic(void *data, void __user *hva, int len)
+{
+ return __copy_from_user_inatomic(data, hva, len);
+}
+
int get_user_page_nowait(struct task_struct *tsk, struct mm_struct *mm,
unsigned long start, int write, struct page **page)
{
return rc == -EHWPOISON;
}
-static pfn_t hva_to_pfn(unsigned long addr, bool atomic, bool *async,
- bool write_fault, bool *writable)
+/*
+ * The atomic path to get the writable pfn which will be stored in @pfn,
+ * true indicates success, otherwise false is returned.
+ */
+static bool hva_to_pfn_fast(unsigned long addr, bool atomic, bool *async,
+ bool write_fault, bool *writable, pfn_t *pfn)
{
struct page *page[1];
- int npages = 0;
- pfn_t pfn;
-
- /* we can do it either atomically or asynchronously, not both */
- BUG_ON(atomic && async);
-
- BUG_ON(!write_fault && !writable);
+ int npages;
- if (writable)
- *writable = true;
+ if (!(async || atomic))
+ return false;
- if (atomic || async)
- npages = __get_user_pages_fast(addr, 1, 1, page);
+ /*
+ * Fast pin a writable pfn only if it is a write fault request
+ * or the caller allows to map a writable pfn for a read fault
+ * request.
+ */
+ if (!(write_fault || writable))
+ return false;
- if (unlikely(npages != 1) && !atomic) {
- might_sleep();
+ npages = __get_user_pages_fast(addr, 1, 1, page);
+ if (npages == 1) {
+ *pfn = page_to_pfn(page[0]);
if (writable)
- *writable = write_fault;
-
- if (async) {
- down_read(¤t->mm->mmap_sem);
- npages = get_user_page_nowait(current, current->mm,
- addr, write_fault, page);
- up_read(¤t->mm->mmap_sem);
- } else
- npages = get_user_pages_fast(addr, 1, write_fault,
- page);
-
- /* map read fault as writable if possible */
- if (unlikely(!write_fault) && npages == 1) {
- struct page *wpage[1];
-
- npages = __get_user_pages_fast(addr, 1, 1, wpage);
- if (npages == 1) {
- *writable = true;
- put_page(page[0]);
- page[0] = wpage[0];
- }
- npages = 1;
- }
+ *writable = true;
+ return true;
}
- if (unlikely(npages != 1)) {
- struct vm_area_struct *vma;
+ return false;
+}
+
+/*
+ * The slow path to get the pfn of the specified host virtual address,
+ * 1 indicates success, -errno is returned if error is detected.
+ */
+static int hva_to_pfn_slow(unsigned long addr, bool *async, bool write_fault,
+ bool *writable, pfn_t *pfn)
+{
+ struct page *page[1];
+ int npages = 0;
+
+ might_sleep();
- if (atomic)
- return KVM_PFN_ERR_FAULT;
+ if (writable)
+ *writable = write_fault;
+ if (async) {
down_read(¤t->mm->mmap_sem);
- if (npages == -EHWPOISON ||
- (!async && check_user_page_hwpoison(addr))) {
- up_read(¤t->mm->mmap_sem);
- return KVM_PFN_ERR_HWPOISON;
- }
-
- vma = find_vma_intersection(current->mm, addr, addr+1);
-
- if (vma == NULL)
- pfn = KVM_PFN_ERR_FAULT;
- else if ((vma->vm_flags & VM_PFNMAP)) {
- pfn = ((addr - vma->vm_start) >> PAGE_SHIFT) +
- vma->vm_pgoff;
- BUG_ON(!kvm_is_mmio_pfn(pfn));
- } else {
- if (async && (vma->vm_flags & VM_WRITE))
- *async = true;
- pfn = KVM_PFN_ERR_FAULT;
- }
+ npages = get_user_page_nowait(current, current->mm,
+ addr, write_fault, page);
up_read(¤t->mm->mmap_sem);
} else
- pfn = page_to_pfn(page[0]);
+ npages = get_user_pages_fast(addr, 1, write_fault,
+ page);
+ if (npages != 1)
+ return npages;
+
+ /* map read fault as writable if possible */
+ if (unlikely(!write_fault) && writable) {
+ struct page *wpage[1];
+
+ npages = __get_user_pages_fast(addr, 1, 1, wpage);
+ if (npages == 1) {
+ *writable = true;
+ put_page(page[0]);
+ page[0] = wpage[0];
+ }
+
+ npages = 1;
+ }
+ *pfn = page_to_pfn(page[0]);
+ return npages;
+}
+
+static bool vma_is_valid(struct vm_area_struct *vma, bool write_fault)
+{
+ if (unlikely(!(vma->vm_flags & VM_READ)))
+ return false;
+
+ if (write_fault && (unlikely(!(vma->vm_flags & VM_WRITE))))
+ return false;
+ return true;
+}
+
+/*
+ * Pin guest page in memory and return its pfn.
+ * @addr: host virtual address which maps memory to the guest
+ * @atomic: whether this function can sleep
+ * @async: whether this function need to wait IO complete if the
+ * host page is not in the memory
+ * @write_fault: whether we should get a writable host page
+ * @writable: whether it allows to map a writable host page for !@write_fault
+ *
+ * The function will map a writable host page for these two cases:
+ * 1): @write_fault = true
+ * 2): @write_fault = false && @writable, @writable will tell the caller
+ * whether the mapping is writable.
+ */
+static pfn_t hva_to_pfn(unsigned long addr, bool atomic, bool *async,
+ bool write_fault, bool *writable)
+{
+ struct vm_area_struct *vma;
+ pfn_t pfn = 0;
+ int npages;
+
+ /* we can do it either atomically or asynchronously, not both */
+ BUG_ON(atomic && async);
+
+ if (hva_to_pfn_fast(addr, atomic, async, write_fault, writable, &pfn))
+ return pfn;
+
+ if (atomic)
+ return KVM_PFN_ERR_FAULT;
+
+ npages = hva_to_pfn_slow(addr, async, write_fault, writable, &pfn);
+ if (npages == 1)
+ return pfn;
+
+ down_read(¤t->mm->mmap_sem);
+ if (npages == -EHWPOISON ||
+ (!async && check_user_page_hwpoison(addr))) {
+ pfn = KVM_PFN_ERR_HWPOISON;
+ goto exit;
+ }
+
+ vma = find_vma_intersection(current->mm, addr, addr + 1);
+
+ if (vma == NULL)
+ pfn = KVM_PFN_ERR_FAULT;
+ else if ((vma->vm_flags & VM_PFNMAP)) {
+ pfn = ((addr - vma->vm_start) >> PAGE_SHIFT) +
+ vma->vm_pgoff;
+ BUG_ON(!kvm_is_mmio_pfn(pfn));
+ } else {
+ if (async && vma_is_valid(vma, write_fault))
+ *async = true;
+ pfn = KVM_PFN_ERR_FAULT;
+ }
+exit:
+ up_read(¤t->mm->mmap_sem);
return pfn;
}
-pfn_t hva_to_pfn_atomic(unsigned long addr)
+static pfn_t
+__gfn_to_pfn_memslot(struct kvm_memory_slot *slot, gfn_t gfn, bool atomic,
+ bool *async, bool write_fault, bool *writable)
{
- return hva_to_pfn(addr, true, NULL, true, NULL);
+ unsigned long addr = __gfn_to_hva_many(slot, gfn, NULL, write_fault);
+
+ if (addr == KVM_HVA_ERR_RO_BAD)
+ return KVM_PFN_ERR_RO_FAULT;
+
+ if (kvm_is_error_hva(addr))
+ return KVM_PFN_ERR_BAD;
+
+ /* Do not map writable pfn in the readonly memslot. */
+ if (writable && memslot_is_readonly(slot)) {
+ *writable = false;
+ writable = NULL;
+ }
+
+ return hva_to_pfn(addr, atomic, async, write_fault,
+ writable);
}
-EXPORT_SYMBOL_GPL(hva_to_pfn_atomic);
static pfn_t __gfn_to_pfn(struct kvm *kvm, gfn_t gfn, bool atomic, bool *async,
bool write_fault, bool *writable)
{
- unsigned long addr;
+ struct kvm_memory_slot *slot;
if (async)
*async = false;
- addr = gfn_to_hva(kvm, gfn);
- if (kvm_is_error_hva(addr))
- return KVM_PFN_ERR_BAD;
+ slot = gfn_to_memslot(kvm, gfn);
- return hva_to_pfn(addr, atomic, async, write_fault, writable);
+ return __gfn_to_pfn_memslot(slot, gfn, atomic, async, write_fault,
+ writable);
}
pfn_t gfn_to_pfn_atomic(struct kvm *kvm, gfn_t gfn)
pfn_t gfn_to_pfn_memslot(struct kvm_memory_slot *slot, gfn_t gfn)
{
- unsigned long addr = gfn_to_hva_memslot(slot, gfn);
- return hva_to_pfn(addr, false, NULL, true, NULL);
+ return __gfn_to_pfn_memslot(slot, gfn, false, NULL, true, NULL);
}
+pfn_t gfn_to_pfn_memslot_atomic(struct kvm_memory_slot *slot, gfn_t gfn)
+{
+ return __gfn_to_pfn_memslot(slot, gfn, true, NULL, true, NULL);
+}
+EXPORT_SYMBOL_GPL(gfn_to_pfn_memslot_atomic);
+
int gfn_to_page_many_atomic(struct kvm *kvm, gfn_t gfn, struct page **pages,
int nr_pages)
{
static struct page *kvm_pfn_to_page(pfn_t pfn)
{
- WARN_ON(kvm_is_mmio_pfn(pfn));
+ if (is_error_pfn(pfn))
+ return KVM_ERR_PTR_BAD_PAGE;
- if (is_error_pfn(pfn) || kvm_is_mmio_pfn(pfn))
- return get_bad_page();
+ if (kvm_is_mmio_pfn(pfn)) {
+ WARN_ON(1);
+ return KVM_ERR_PTR_BAD_PAGE;
+ }
return pfn_to_page(pfn);
}
void kvm_release_page_clean(struct page *page)
{
- if (!is_error_page(page))
- kvm_release_pfn_clean(page_to_pfn(page));
+ WARN_ON(is_error_page(page));
+
+ kvm_release_pfn_clean(page_to_pfn(page));
}
EXPORT_SYMBOL_GPL(kvm_release_page_clean);
void kvm_release_pfn_clean(pfn_t pfn)
{
- if (!is_error_pfn(pfn) && !kvm_is_mmio_pfn(pfn))
+ WARN_ON(is_error_pfn(pfn));
+
+ if (!kvm_is_mmio_pfn(pfn))
put_page(pfn_to_page(pfn));
}
EXPORT_SYMBOL_GPL(kvm_release_pfn_clean);
int r;
unsigned long addr;
- addr = gfn_to_hva(kvm, gfn);
+ addr = gfn_to_hva_read(kvm, gfn);
if (kvm_is_error_hva(addr))
return -EFAULT;
- r = __copy_from_user(data, (void __user *)addr + offset, len);
+ r = kvm_read_hva(data, (void __user *)addr + offset, len);
if (r)
return -EFAULT;
return 0;
gfn_t gfn = gpa >> PAGE_SHIFT;
int offset = offset_in_page(gpa);
- addr = gfn_to_hva(kvm, gfn);
+ addr = gfn_to_hva_read(kvm, gfn);
if (kvm_is_error_hva(addr))
return -EFAULT;
pagefault_disable();
- r = __copy_from_user_inatomic(data, (void __user *)addr + offset, len);
+ r = kvm_read_hva_atomic(data, (void __user *)addr + offset, len);
pagefault_enable();
if (r)
return -EFAULT;
#endif
- vcpu_load(vcpu);
+ r = vcpu_load(vcpu);
+ if (r)
+ return r;
switch (ioctl) {
case KVM_RUN:
r = -EINVAL;
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