[PATCH v5 05/14] nEPT: make guest's A/D bits depends on guest's paging mode

Gleb Natapov
2013-07-31T14:49:08Z

This patch makes guest A/D bits definition to be dependable on paging
mode, so when EPT support will be added it will be able to define them
differently.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
---
arch/x86/kvm/paging_tmpl.h | 30 ++++++++++++++++++++++--------
1 file changed, 22 insertions(+), 8 deletions(-)

diff --git a/arch/x86/kvm/paging_tmpl.h b/arch/x86/kvm/paging_tmpl.h
index fb26ca9..7581395 100644
--- a/arch/x86/kvm/paging_tmpl.h
+++ b/arch/x86/kvm/paging_tmpl.h
@@ -32,6 +32,10 @@
#define PT_LVL_OFFSET_MASK(lvl) PT64_LVL_OFFSET_MASK(lvl)
#define PT_INDEX(addr, level) PT64_INDEX(addr, level)
#define PT_LEVEL_BITS PT64_LEVEL_BITS
+ #define PT_GUEST_ACCESSED_MASK PT_ACCESSED_MASK
+ #define PT_GUEST_DIRTY_MASK PT_DIRTY_MASK
+ #define PT_GUEST_DIRTY_SHIFT PT_DIRTY_SHIFT
+ #define PT_GUEST_ACCESSED_SHIFT PT_ACCESSED_SHIFT
#ifdef CONFIG_X86_64
#define PT_MAX_FULL_LEVELS 4
#define CMPXCHG cmpxchg
@@ -49,6 +53,10 @@
#define PT_INDEX(addr, level) PT32_INDEX(addr, level)
#define PT_LEVEL_BITS PT32_LEVEL_BITS
#define PT_MAX_FULL_LEVELS 2
+ #define PT_GUEST_ACCESSED_MASK PT_ACCESSED_MASK
+ #define PT_GUEST_DIRTY_MASK PT_DIRTY_MASK
+ #define PT_GUEST_DIRTY_SHIFT PT_DIRTY_SHIFT
+ #define PT_GUEST_ACCESSED_SHIFT PT_ACCESSED_SHIFT
#define CMPXCHG cmpxchg
#else
#error Invalid PTTYPE value
@@ -88,7 +96,8 @@ static inline void FNAME(protect_clean_gpte)(unsigned *access, unsigned gpte)

mask = (unsigned)~ACC_WRITE_MASK;
/* Allow write access to dirty gptes */
- mask |= (gpte >> (PT_DIRTY_SHIFT - PT_WRITABLE_SHIFT)) & PT_WRITABLE_MASK;
+ mask |= (gpte >> (PT_GUEST_DIRTY_SHIFT - PT_WRITABLE_SHIFT)) &
+ PT_WRITABLE_MASK;
*access &= mask;
}

@@ -138,7 +147,7 @@ static bool FNAME(prefetch_invalid_gpte)(struct kvm_vcpu *vcpu,
if (!FNAME(is_present_gpte)(gpte))
goto no_present;

- if (!(gpte & PT_ACCESSED_MASK))
+ if (!(gpte & PT_GUEST_ACCESSED_MASK))
goto no_present;

return false;
@@ -174,14 +183,14 @@ static int FNAME(update_accessed_dirty_bits)(struct kvm_vcpu *vcpu,
table_gfn = walker->table_gfn[level - 1];
ptep_user = walker->ptep_user[level - 1];
index = offset_in_page(ptep_user) / sizeof(pt_element_t);
- if (!(pte & PT_ACCESSED_MASK)) {
+ if (!(pte & PT_GUEST_ACCESSED_MASK)) {
trace_kvm_mmu_set_accessed_bit(table_gfn, index, sizeof(pte));
- pte |= PT_ACCESSED_MASK;
+ pte |= PT_GUEST_ACCESSED_MASK;
}
if (level == walker->level && write_fault &&
- !(pte & PT_DIRTY_MASK)) {
+ !(pte & PT_GUEST_DIRTY_MASK)) {
trace_kvm_mmu_set_dirty_bit(table_gfn, index, sizeof(pte));
- pte |= PT_DIRTY_MASK;
+ pte |= PT_GUEST_DIRTY_MASK;
}
if (pte == orig_pte)
continue;
@@ -235,7 +244,7 @@ retry_walk:
ASSERT((!is_long_mode(vcpu) && is_pae(vcpu)) ||
(mmu->get_cr3(vcpu) & CR3_NONPAE_RESERVED_BITS) == 0);

- accessed_dirty = PT_ACCESSED_MASK;
+ accessed_dirty = PT_GUEST_ACCESSED_MASK;
pt_access = pte_access = ACC_ALL;
++walker->level;

@@ -310,7 +319,8 @@ retry_walk:
* On a write fault, fold the dirty bit into accessed_dirty by
* shifting it one place right.
*/
- accessed_dirty &= pte >> (PT_DIRTY_SHIFT - PT_ACCESSED_SHIFT);
+ accessed_dirty &= pte >>
+ (PT_GUEST_DIRTY_SHIFT - PT_GUEST_ACCESSED_SHIFT);

if (unlikely(!accessed_dirty)) {
ret = FNAME(update_accessed_dirty_bits)(vcpu, mmu, walker, write_fault);
@@ -886,3 +896,7 @@ static int FNAME(sync_page)(struct kvm_vcpu *vcpu, struct kvm_mmu_page *sp)
#undef gpte_to_gfn
#undef gpte_to_gfn_lvl
#undef CMPXCHG
+#undef PT_GUEST_ACCESSED_MASK
+#undef PT_GUEST_DIRTY_MASK
+#undef PT_GUEST_DIRTY_SHIFT
+#undef PT_GUEST_ACCESSED_SHIFT
--
1.7.10.4