The PAT bit gets relocated to bit 12 when PUD and PMD mappings are
used. This bit 12, however, is not covered by PTE_FLAGS_MASK, which
is used for masking pfn and flags for all levels.
Add pud/pmd mask interfaces to handle pfn and flags properly by using
P?D_PAGE_MASK when PUD/PMD mappings are used, i.e. PSE bit is set.
Suggested-by: Juergen Gross <jgross@xxxxxxxx>
Signed-off-by: Toshi Kani <toshi.kani@xxxxxxx>
Cc: Juergen Gross <jgross@xxxxxxxx>
Cc: Konrad Wilk <konrad.wilk@xxxxxxxxxx>
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: H. Peter Anvin <hpa@xxxxxxxxx>
Cc: Ingo Molnar <mingo@xxxxxxxxxx>
Cc: Borislav Petkov <bp@xxxxxxxxx>
---
arch/x86/include/asm/pgtable_types.h | 36 ++++++++++++++++++++++++++++++++--
1 file changed, 34 insertions(+), 2 deletions(-)
diff --git a/arch/x86/include/asm/pgtable_types.h b/arch/x86/include/asm/pgtable_types.h
index 13f310b..7c8f797 100644
--- a/arch/x86/include/asm/pgtable_types.h
+++ b/arch/x86/include/asm/pgtable_types.h
@@ -209,10 +209,10 @@ enum page_cache_mode {
#include <linux/types.h>
-/* PTE_PFN_MASK extracts the PFN from a (pte|pmd|pud|pgd)val_t */
+/* Extracts the PFN from a (pte|pmd|pud|pgd)val_t of a 4KB page */
#define PTE_PFN_MASK ((pteval_t)PHYSICAL_PAGE_MASK)
-/* PTE_FLAGS_MASK extracts the flags from a (pte|pmd|pud|pgd)val_t */
+/* Extracts the flags from a (pte|pmd|pud|pgd)val_t of a 4KB page */
#define PTE_FLAGS_MASK (~PTE_PFN_MASK)
typedef struct pgprot { pgprotval_t pgprot; } pgprot_t;
@@ -276,11 +276,43 @@ static inline pmdval_t native_pmd_val(pmd_t pmd)
}
#endif
+static inline pudval_t pud_pfn_mask(pud_t pud)
+{
+ if (native_pud_val(pud) & _PAGE_PSE)
+ return PUD_PAGE_MASK & PHYSICAL_PAGE_MASK;
+ else
+ return PTE_PFN_MASK;
+}
+
+static inline pudval_t pud_flags_mask(pud_t pud)
+{
+ if (native_pud_val(pud) & _PAGE_PSE)
+ return ~(PUD_PAGE_MASK & (pudval_t)PHYSICAL_PAGE_MASK);
+ else
+ return ~PTE_PFN_MASK;
+}
+
static inline pudval_t pud_flags(pud_t pud)
{
return native_pud_val(pud) & PTE_FLAGS_MASK;
}
+static inline pmdval_t pmd_pfn_mask(pmd_t pmd)
+{
+ if (native_pmd_val(pmd) & _PAGE_PSE)
+ return PMD_PAGE_MASK & PHYSICAL_PAGE_MASK;
+ else
+ return PTE_PFN_MASK;
+}
+
+static inline pmdval_t pmd_flags_mask(pmd_t pmd)
+{
+ if (native_pmd_val(pmd) & _PAGE_PSE)
+ return ~(PMD_PAGE_MASK & (pmdval_t)PHYSICAL_PAGE_MASK);
+ else
+ return ~PTE_PFN_MASK;
+}
+
static inline pmdval_t pmd_flags(pmd_t pmd)
{
return native_pmd_val(pmd) & PTE_FLAGS_MASK;
--
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