Commit d3fccc7e authored by Ard Biesheuvel's avatar Ard Biesheuvel Committed by Paolo Bonzini

kvm: fix kvm_is_mmio_pfn() and rename to kvm_is_reserved_pfn()

This reverts commit 85c8555f ("KVM: check for !is_zero_pfn() in
kvm_is_mmio_pfn()") and renames the function to kvm_is_reserved_pfn.

The problem being addressed by the patch above was that some ARM code
based the memory mapping attributes of a pfn on the return value of
kvm_is_mmio_pfn(), whose name indeed suggests that such pfns should
be mapped as device memory.

However, kvm_is_mmio_pfn() doesn't do quite what it says on the tin,
and the existing non-ARM users were already using it in a way which
suggests that its name should probably have been 'kvm_is_reserved_pfn'
from the beginning, e.g., whether or not to call get_page/put_page on
it etc. This means that returning false for the zero page is a mistake
and the patch above should be reverted.
Signed-off-by: default avatarArd Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: default avatarPaolo Bonzini <pbonzini@redhat.com>
parent bb55e9b1
...@@ -1563,7 +1563,7 @@ int kvm_arch_prepare_memory_region(struct kvm *kvm, ...@@ -1563,7 +1563,7 @@ int kvm_arch_prepare_memory_region(struct kvm *kvm,
for (i = 0; i < npages; i++) { for (i = 0; i < npages; i++) {
pfn = gfn_to_pfn(kvm, base_gfn + i); pfn = gfn_to_pfn(kvm, base_gfn + i);
if (!kvm_is_mmio_pfn(pfn)) { if (!kvm_is_reserved_pfn(pfn)) {
kvm_set_pmt_entry(kvm, base_gfn + i, kvm_set_pmt_entry(kvm, base_gfn + i,
pfn << PAGE_SHIFT, pfn << PAGE_SHIFT,
_PAGE_AR_RWX | _PAGE_MA_WB); _PAGE_AR_RWX | _PAGE_MA_WB);
......
...@@ -630,7 +630,7 @@ static int mmu_spte_clear_track_bits(u64 *sptep) ...@@ -630,7 +630,7 @@ static int mmu_spte_clear_track_bits(u64 *sptep)
* kvm mmu, before reclaiming the page, we should * kvm mmu, before reclaiming the page, we should
* unmap it from mmu first. * unmap it from mmu first.
*/ */
WARN_ON(!kvm_is_mmio_pfn(pfn) && !page_count(pfn_to_page(pfn))); WARN_ON(!kvm_is_reserved_pfn(pfn) && !page_count(pfn_to_page(pfn)));
if (!shadow_accessed_mask || old_spte & shadow_accessed_mask) if (!shadow_accessed_mask || old_spte & shadow_accessed_mask)
kvm_set_pfn_accessed(pfn); kvm_set_pfn_accessed(pfn);
...@@ -2461,7 +2461,7 @@ static int set_spte(struct kvm_vcpu *vcpu, u64 *sptep, ...@@ -2461,7 +2461,7 @@ static int set_spte(struct kvm_vcpu *vcpu, u64 *sptep,
spte |= PT_PAGE_SIZE_MASK; spte |= PT_PAGE_SIZE_MASK;
if (tdp_enabled) if (tdp_enabled)
spte |= kvm_x86_ops->get_mt_mask(vcpu, gfn, spte |= kvm_x86_ops->get_mt_mask(vcpu, gfn,
kvm_is_mmio_pfn(pfn)); kvm_is_reserved_pfn(pfn));
if (host_writable) if (host_writable)
spte |= SPTE_HOST_WRITEABLE; spte |= SPTE_HOST_WRITEABLE;
...@@ -2737,7 +2737,7 @@ static void transparent_hugepage_adjust(struct kvm_vcpu *vcpu, ...@@ -2737,7 +2737,7 @@ static void transparent_hugepage_adjust(struct kvm_vcpu *vcpu,
* PT_PAGE_TABLE_LEVEL and there would be no adjustment done * PT_PAGE_TABLE_LEVEL and there would be no adjustment done
* here. * here.
*/ */
if (!is_error_noslot_pfn(pfn) && !kvm_is_mmio_pfn(pfn) && if (!is_error_noslot_pfn(pfn) && !kvm_is_reserved_pfn(pfn) &&
level == PT_PAGE_TABLE_LEVEL && level == PT_PAGE_TABLE_LEVEL &&
PageTransCompound(pfn_to_page(pfn)) && PageTransCompound(pfn_to_page(pfn)) &&
!has_wrprotected_page(vcpu->kvm, gfn, PT_DIRECTORY_LEVEL)) { !has_wrprotected_page(vcpu->kvm, gfn, PT_DIRECTORY_LEVEL)) {
......
...@@ -703,7 +703,7 @@ void kvm_arch_sync_events(struct kvm *kvm); ...@@ -703,7 +703,7 @@ void kvm_arch_sync_events(struct kvm *kvm);
int kvm_cpu_has_pending_timer(struct kvm_vcpu *vcpu); int kvm_cpu_has_pending_timer(struct kvm_vcpu *vcpu);
void kvm_vcpu_kick(struct kvm_vcpu *vcpu); void kvm_vcpu_kick(struct kvm_vcpu *vcpu);
bool kvm_is_mmio_pfn(pfn_t pfn); bool kvm_is_reserved_pfn(pfn_t pfn);
struct kvm_irq_ack_notifier { struct kvm_irq_ack_notifier {
struct hlist_node link; struct hlist_node link;
......
...@@ -107,10 +107,10 @@ EXPORT_SYMBOL_GPL(kvm_rebooting); ...@@ -107,10 +107,10 @@ EXPORT_SYMBOL_GPL(kvm_rebooting);
static bool largepages_enabled = true; static bool largepages_enabled = true;
bool kvm_is_mmio_pfn(pfn_t pfn) bool kvm_is_reserved_pfn(pfn_t pfn)
{ {
if (pfn_valid(pfn)) if (pfn_valid(pfn))
return !is_zero_pfn(pfn) && PageReserved(pfn_to_page(pfn)); return PageReserved(pfn_to_page(pfn));
return true; return true;
} }
...@@ -1321,7 +1321,7 @@ static pfn_t hva_to_pfn(unsigned long addr, bool atomic, bool *async, ...@@ -1321,7 +1321,7 @@ static pfn_t hva_to_pfn(unsigned long addr, bool atomic, bool *async,
else if ((vma->vm_flags & VM_PFNMAP)) { else if ((vma->vm_flags & VM_PFNMAP)) {
pfn = ((addr - vma->vm_start) >> PAGE_SHIFT) + pfn = ((addr - vma->vm_start) >> PAGE_SHIFT) +
vma->vm_pgoff; vma->vm_pgoff;
BUG_ON(!kvm_is_mmio_pfn(pfn)); BUG_ON(!kvm_is_reserved_pfn(pfn));
} else { } else {
if (async && vma_is_valid(vma, write_fault)) if (async && vma_is_valid(vma, write_fault))
*async = true; *async = true;
...@@ -1427,7 +1427,7 @@ static struct page *kvm_pfn_to_page(pfn_t pfn) ...@@ -1427,7 +1427,7 @@ static struct page *kvm_pfn_to_page(pfn_t pfn)
if (is_error_noslot_pfn(pfn)) if (is_error_noslot_pfn(pfn))
return KVM_ERR_PTR_BAD_PAGE; return KVM_ERR_PTR_BAD_PAGE;
if (kvm_is_mmio_pfn(pfn)) { if (kvm_is_reserved_pfn(pfn)) {
WARN_ON(1); WARN_ON(1);
return KVM_ERR_PTR_BAD_PAGE; return KVM_ERR_PTR_BAD_PAGE;
} }
...@@ -1456,7 +1456,7 @@ EXPORT_SYMBOL_GPL(kvm_release_page_clean); ...@@ -1456,7 +1456,7 @@ EXPORT_SYMBOL_GPL(kvm_release_page_clean);
void kvm_release_pfn_clean(pfn_t pfn) void kvm_release_pfn_clean(pfn_t pfn)
{ {
if (!is_error_noslot_pfn(pfn) && !kvm_is_mmio_pfn(pfn)) if (!is_error_noslot_pfn(pfn) && !kvm_is_reserved_pfn(pfn))
put_page(pfn_to_page(pfn)); put_page(pfn_to_page(pfn));
} }
EXPORT_SYMBOL_GPL(kvm_release_pfn_clean); EXPORT_SYMBOL_GPL(kvm_release_pfn_clean);
...@@ -1477,7 +1477,7 @@ static void kvm_release_pfn_dirty(pfn_t pfn) ...@@ -1477,7 +1477,7 @@ static void kvm_release_pfn_dirty(pfn_t pfn)
void kvm_set_pfn_dirty(pfn_t pfn) void kvm_set_pfn_dirty(pfn_t pfn)
{ {
if (!kvm_is_mmio_pfn(pfn)) { if (!kvm_is_reserved_pfn(pfn)) {
struct page *page = pfn_to_page(pfn); struct page *page = pfn_to_page(pfn);
if (!PageReserved(page)) if (!PageReserved(page))
SetPageDirty(page); SetPageDirty(page);
...@@ -1487,14 +1487,14 @@ EXPORT_SYMBOL_GPL(kvm_set_pfn_dirty); ...@@ -1487,14 +1487,14 @@ EXPORT_SYMBOL_GPL(kvm_set_pfn_dirty);
void kvm_set_pfn_accessed(pfn_t pfn) void kvm_set_pfn_accessed(pfn_t pfn)
{ {
if (!kvm_is_mmio_pfn(pfn)) if (!kvm_is_reserved_pfn(pfn))
mark_page_accessed(pfn_to_page(pfn)); mark_page_accessed(pfn_to_page(pfn));
} }
EXPORT_SYMBOL_GPL(kvm_set_pfn_accessed); EXPORT_SYMBOL_GPL(kvm_set_pfn_accessed);
void kvm_get_pfn(pfn_t pfn) void kvm_get_pfn(pfn_t pfn)
{ {
if (!kvm_is_mmio_pfn(pfn)) if (!kvm_is_reserved_pfn(pfn))
get_page(pfn_to_page(pfn)); get_page(pfn_to_page(pfn));
} }
EXPORT_SYMBOL_GPL(kvm_get_pfn); EXPORT_SYMBOL_GPL(kvm_get_pfn);
......
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