diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h
index 1993eb1cb2cd4b695a149d92db5f36e791d29ea0..4e60d3695e4ec91f784f13d830bade500d01507a 100644
--- a/include/linux/kvm_host.h
+++ b/include/linux/kvm_host.h
@@ -423,6 +423,7 @@ void kvm_arch_flush_shadow(struct kvm *kvm);
int gfn_to_page_many_atomic(struct kvm *kvm, gfn_t gfn, struct page **pages,
int nr_pages);
+struct page *get_bad_page(void);
struct page *gfn_to_page(struct kvm *kvm, gfn_t gfn);
unsigned long gfn_to_hva(struct kvm *kvm, gfn_t gfn);
void kvm_release_page_clean(struct page *page);
@@ -576,7 +577,7 @@ void kvm_arch_sync_events(struct kvm *kvm);
int kvm_cpu_has_pending_timer(struct kvm_vcpu *vcpu);
void kvm_vcpu_kick(struct kvm_vcpu *vcpu);
-int kvm_is_mmio_pfn(pfn_t pfn);
+bool kvm_is_mmio_pfn(pfn_t pfn);
struct kvm_irq_ack_notifier {
struct hlist_node link;
diff --git a/virt/kvm/async_pf.c b/virt/kvm/async_pf.c
index ebae24b62c90ec7af4270c2097b1182593c00b7d..79722782d9d7227e5179a92a14833e2f32ce5d1c 100644
--- a/virt/kvm/async_pf.c
+++ b/virt/kvm/async_pf.c
@@ -203,8 +203,7 @@ int kvm_async_pf_wakeup_all(struct kvm_vcpu *vcpu)
if (!work)
return -ENOMEM;
- work->page = bad_page;
- get_page(bad_page);
+ work->page = get_bad_page();
INIT_LIST_HEAD(&work->queue); /* for list_del to work */
spin_lock(&vcpu->async_pf.lock);
diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index 0014ee99dc7f9394c6139faffe0b590f9ab233fd..de89497fe4c77264f0008d5f78c36cb24515e796 100644
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -100,17 +100,11 @@ EXPORT_SYMBOL_GPL(kvm_rebooting);
static bool largepages_enabled = true;
-struct page *bad_page;
-static pfn_t bad_pfn;
-
-static struct page *hwpoison_page;
-static pfn_t hwpoison_pfn;
-
-static struct page *fault_page;
-static pfn_t fault_pfn;
-
-inline int kvm_is_mmio_pfn(pfn_t pfn)
+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);
@@ -939,34 +933,55 @@ EXPORT_SYMBOL_GPL(kvm_disable_largepages);
int is_error_page(struct page *page)
{
- return page == bad_page || page == hwpoison_page || page == fault_page;
+ return IS_ERR(page);
}
EXPORT_SYMBOL_GPL(is_error_page);
int is_error_pfn(pfn_t pfn)
{
- return pfn == bad_pfn || pfn == hwpoison_pfn || pfn == fault_pfn;
+ return IS_ERR_VALUE(pfn);
}
EXPORT_SYMBOL_GPL(is_error_pfn);
+static pfn_t get_bad_pfn(void)
+{
+ return -ENOENT;
+}
+
+pfn_t get_fault_pfn(void)
+{
+ return -EFAULT;
+}
+EXPORT_SYMBOL_GPL(get_fault_pfn);
+
+static pfn_t get_hwpoison_pfn(void)
+{
+ return -EHWPOISON;
+}
+
int is_hwpoison_pfn(pfn_t pfn)
{
- return pfn == hwpoison_pfn;
+ return pfn == -EHWPOISON;
}
EXPORT_SYMBOL_GPL(is_hwpoison_pfn);
int is_noslot_pfn(pfn_t pfn)
{
- return pfn == bad_pfn;
+ return pfn == -ENOENT;
}
EXPORT_SYMBOL_GPL(is_noslot_pfn);
int is_invalid_pfn(pfn_t pfn)
{
- return pfn == hwpoison_pfn || pfn == fault_pfn;
+ return !is_noslot_pfn(pfn) && is_error_pfn(pfn);
}
EXPORT_SYMBOL_GPL(is_invalid_pfn);
+struct page *get_bad_page(void)
+{
+ return ERR_PTR(-ENOENT);
+}
+
static inline unsigned long bad_hva(void)
{
return PAGE_OFFSET;
@@ -1038,13 +1053,6 @@ unsigned long gfn_to_hva(struct kvm *kvm, gfn_t gfn)
}
EXPORT_SYMBOL_GPL(gfn_to_hva);
-pfn_t get_fault_pfn(void)
-{
- get_page(fault_page);
- return fault_pfn;
-}
-EXPORT_SYMBOL_GPL(get_fault_pfn);
-
int get_user_page_nowait(struct task_struct *tsk, struct mm_struct *mm,
unsigned long start, int write, struct page **page)
{
@@ -1122,8 +1130,7 @@ static pfn_t hva_to_pfn(unsigned long addr, bool atomic, bool *async,
if (npages == -EHWPOISON ||
(!async && check_user_page_hwpoison(addr))) {
up_read(¤t->mm->mmap_sem);
- get_page(hwpoison_page);
- return page_to_pfn(hwpoison_page);
+ return get_hwpoison_pfn();
}
vma = find_vma_intersection(current->mm, addr, addr+1);
@@ -1161,10 +1168,8 @@ static pfn_t __gfn_to_pfn(struct kvm *kvm, gfn_t gfn, bool atomic, bool *async,
*async = false;
addr = gfn_to_hva(kvm, gfn);
- if (kvm_is_error_hva(addr)) {
- get_page(bad_page);
- return page_to_pfn(bad_page);
- }
+ if (kvm_is_error_hva(addr))
+ return get_bad_pfn();
return hva_to_pfn(addr, atomic, async, write_fault, writable);
}
@@ -1218,37 +1223,45 @@ int gfn_to_page_many_atomic(struct kvm *kvm, gfn_t gfn, struct page **pages,
}
EXPORT_SYMBOL_GPL(gfn_to_page_many_atomic);
+static struct page *kvm_pfn_to_page(pfn_t pfn)
+{
+ WARN_ON(kvm_is_mmio_pfn(pfn));
+
+ if (is_error_pfn(pfn) || kvm_is_mmio_pfn(pfn))
+ return get_bad_page();
+
+ return pfn_to_page(pfn);
+}
+
struct page *gfn_to_page(struct kvm *kvm, gfn_t gfn)
{
pfn_t pfn;
pfn = gfn_to_pfn(kvm, gfn);
- if (!kvm_is_mmio_pfn(pfn))
- return pfn_to_page(pfn);
-
- WARN_ON(kvm_is_mmio_pfn(pfn));
- get_page(bad_page);
- return bad_page;
+ return kvm_pfn_to_page(pfn);
}
EXPORT_SYMBOL_GPL(gfn_to_page);
void kvm_release_page_clean(struct page *page)
{
- kvm_release_pfn_clean(page_to_pfn(page));
+ if (!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 (!kvm_is_mmio_pfn(pfn))
+ if (!is_error_pfn(pfn) && !kvm_is_mmio_pfn(pfn))
put_page(pfn_to_page(pfn));
}
EXPORT_SYMBOL_GPL(kvm_release_pfn_clean);
void kvm_release_page_dirty(struct page *page)
{
+ WARN_ON(is_error_page(page));
+
kvm_release_pfn_dirty(page_to_pfn(page));
}
EXPORT_SYMBOL_GPL(kvm_release_page_dirty);
@@ -2771,33 +2784,6 @@ int kvm_init(void *opaque, unsigned vcpu_size, unsigned vcpu_align,
if (r)
goto out_fail;
- bad_page = alloc_page(GFP_KERNEL | __GFP_ZERO);
-
- if (bad_page == NULL) {
- r = -ENOMEM;
- goto out;
- }
-
- bad_pfn = page_to_pfn(bad_page);
-
- hwpoison_page = alloc_page(GFP_KERNEL | __GFP_ZERO);
-
- if (hwpoison_page == NULL) {
- r = -ENOMEM;
- goto out_free_0;
- }
-
- hwpoison_pfn = page_to_pfn(hwpoison_page);
-
- fault_page = alloc_page(GFP_KERNEL | __GFP_ZERO);
-
- if (fault_page == NULL) {
- r = -ENOMEM;
- goto out_free_0;
- }
-
- fault_pfn = page_to_pfn(fault_page);
-
if (!zalloc_cpumask_var(&cpus_hardware_enabled, GFP_KERNEL)) {
r = -ENOMEM;
goto out_free_0;
@@ -2872,12 +2858,6 @@ int kvm_init(void *opaque, unsigned vcpu_size, unsigned vcpu_align,
out_free_0a:
free_cpumask_var(cpus_hardware_enabled);
out_free_0:
- if (fault_page)
- __free_page(fault_page);
- if (hwpoison_page)
- __free_page(hwpoison_page);
- __free_page(bad_page);
-out:
kvm_arch_exit();
out_fail:
return r;
@@ -2897,8 +2877,5 @@ void kvm_exit(void)
kvm_arch_hardware_unsetup();
kvm_arch_exit();
free_cpumask_var(cpus_hardware_enabled);
- __free_page(fault_page);
- __free_page(hwpoison_page);
- __free_page(bad_page);
}
EXPORT_SYMBOL_GPL(kvm_exit);