arm64: handle 52-bit physical addresses in page table entries

The top 4 bits of a 52-bit physical address are positioned at bits
12..15 of a page table entry. Introduce macros to convert between a
physical address and its placement in a table entry, and change all
macros/functions that access PTEs to use them.

Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Tested-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Tested-by: Bob Picco <bob.picco@oracle.com>
Reviewed-by: Bob Picco <bob.picco@oracle.com>
Signed-off-by: Kristina Martsenko <kristina.martsenko@arm.com>
[catalin.marinas@arm.com: some long lines wrapped]
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>

1 files changed, 38 insertions, 12 deletions

diff --git a/arch/arm64/include/asm/pgtable.h b/arch/arm64/include/asm/pgtable.h
index 5d9554fb2692..4fd8af303e2c 100644
--- a/arch/arm64/include/asm/pgtable.h
+++ b/arch/arm64/include/asm/pgtable.h
@@ -57,9 +57,22 @@ extern unsigned long empty_zero_page[PAGE_SIZE / sizeof(unsigned long)];
 
 #define pte_ERROR(pte)		__pte_error(__FILE__, __LINE__, pte_val(pte))
 
-#define pte_pfn(pte)		((pte_val(pte) & PHYS_MASK) >> PAGE_SHIFT)
+/*
+ * Macros to convert between a physical address and its placement in a
+ * page table entry, taking care of 52-bit addresses.
+ */
+#ifdef CONFIG_ARM64_PA_BITS_52
+#define __pte_to_phys(pte)	\
+	((pte_val(pte) & PTE_ADDR_LOW) | ((pte_val(pte) & PTE_ADDR_HIGH) << 36))
+#define __phys_to_pte_val(phys)	(((phys) | ((phys) >> 36)) & PTE_ADDR_MASK)
+#else
+#define __pte_to_phys(pte)	(pte_val(pte) & PTE_ADDR_MASK)
+#define __phys_to_pte_val(phys)	(phys)
+#endif
 
-#define pfn_pte(pfn,prot)	(__pte(((phys_addr_t)(pfn) << PAGE_SHIFT) | pgprot_val(prot)))
+#define pte_pfn(pte)		(__pte_to_phys(pte) >> PAGE_SHIFT)
+#define pfn_pte(pfn,prot)	\
+	__pte(__phys_to_pte_val((phys_addr_t)(pfn) << PAGE_SHIFT) | pgprot_val(prot))
 
 #define pte_none(pte)		(!pte_val(pte))
 #define pte_clear(mm,addr,ptep)	set_pte(ptep, __pte(0))
@@ -284,6 +297,11 @@ static inline int pte_same(pte_t pte_a, pte_t pte_b)
 
 #define __HAVE_ARCH_PTE_SPECIAL
 
+static inline pte_t pgd_pte(pgd_t pgd)
+{
+	return __pte(pgd_val(pgd));
+}
+
 static inline pte_t pud_pte(pud_t pud)
 {
 	return __pte(pud_val(pud));
@@ -349,16 +367,24 @@ static inline int pmd_protnone(pmd_t pmd)
 
 #define pmd_mkhuge(pmd)		(__pmd(pmd_val(pmd) & ~PMD_TABLE_BIT))
 
-#define pmd_pfn(pmd)		(((pmd_val(pmd) & PMD_MASK) & PHYS_MASK) >> PAGE_SHIFT)
-#define pfn_pmd(pfn,prot)	(__pmd(((phys_addr_t)(pfn) << PAGE_SHIFT) | pgprot_val(prot)))
+#define __pmd_to_phys(pmd)	__pte_to_phys(pmd_pte(pmd))
+#define __phys_to_pmd_val(phys)	__phys_to_pte_val(phys)
+#define pmd_pfn(pmd)		((__pmd_to_phys(pmd) & PMD_MASK) >> PAGE_SHIFT)
+#define pfn_pmd(pfn,prot)	__pmd(__phys_to_pmd_val((phys_addr_t)(pfn) << PAGE_SHIFT) | pgprot_val(prot))
 #define mk_pmd(page,prot)	pfn_pmd(page_to_pfn(page),prot)
 
 #define pud_write(pud)		pte_write(pud_pte(pud))
-#define pud_pfn(pud)		(((pud_val(pud) & PUD_MASK) & PHYS_MASK) >> PAGE_SHIFT)
-#define pfn_pud(pfn,prot)	(__pud(((phys_addr_t)(pfn) << PAGE_SHIFT) | pgprot_val(prot)))
+
+#define __pud_to_phys(pud)	__pte_to_phys(pud_pte(pud))
+#define __phys_to_pud_val(phys)	__phys_to_pte_val(phys)
+#define pud_pfn(pud)		((__pud_to_phys(pud) & PUD_MASK) >> PAGE_SHIFT)
+#define pfn_pud(pfn,prot)	__pud(__phys_to_pud_val((phys_addr_t)(pfn) << PAGE_SHIFT) | pgprot_val(prot))
 
 #define set_pmd_at(mm, addr, pmdp, pmd)	set_pte_at(mm, addr, (pte_t *)pmdp, pmd_pte(pmd))
 
+#define __pgd_to_phys(pgd)	__pte_to_phys(pgd_pte(pgd))
+#define __phys_to_pgd_val(phys)	__phys_to_pte_val(phys)
+
 #define __pgprot_modify(prot,mask,bits) \
 	__pgprot((pgprot_val(prot) & ~(mask)) | (bits))
 
@@ -409,7 +435,7 @@ static inline void pmd_clear(pmd_t *pmdp)
 
 static inline phys_addr_t pmd_page_paddr(pmd_t pmd)
 {
-	return pmd_val(pmd) & PHYS_MASK & (s32)PAGE_MASK;
+	return __pmd_to_phys(pmd);
 }
 
 /* Find an entry in the third-level page table. */
@@ -427,7 +453,7 @@ static inline phys_addr_t pmd_page_paddr(pmd_t pmd)
 #define pte_set_fixmap_offset(pmd, addr)	pte_set_fixmap(pte_offset_phys(pmd, addr))
 #define pte_clear_fixmap()		clear_fixmap(FIX_PTE)
 
-#define pmd_page(pmd)		pfn_to_page(__phys_to_pfn(pmd_val(pmd) & PHYS_MASK))
+#define pmd_page(pmd)		pfn_to_page(__phys_to_pfn(__pmd_to_phys(pmd)))
 
 /* use ONLY for statically allocated translation tables */
 #define pte_offset_kimg(dir,addr)	((pte_t *)__phys_to_kimg(pte_offset_phys((dir), (addr))))
@@ -460,7 +486,7 @@ static inline void pud_clear(pud_t *pudp)
 
 static inline phys_addr_t pud_page_paddr(pud_t pud)
 {
-	return pud_val(pud) & PHYS_MASK & (s32)PAGE_MASK;
+	return __pud_to_phys(pud);
 }
 
 /* Find an entry in the second-level page table. */
@@ -473,7 +499,7 @@ static inline phys_addr_t pud_page_paddr(pud_t pud)
 #define pmd_set_fixmap_offset(pud, addr)	pmd_set_fixmap(pmd_offset_phys(pud, addr))
 #define pmd_clear_fixmap()		clear_fixmap(FIX_PMD)
 
-#define pud_page(pud)		pfn_to_page(__phys_to_pfn(pud_val(pud) & PHYS_MASK))
+#define pud_page(pud)		pfn_to_page(__phys_to_pfn(__pud_to_phys(pud)))
 
 /* use ONLY for statically allocated translation tables */
 #define pmd_offset_kimg(dir,addr)	((pmd_t *)__phys_to_kimg(pmd_offset_phys((dir), (addr))))
@@ -512,7 +538,7 @@ static inline void pgd_clear(pgd_t *pgdp)
 
 static inline phys_addr_t pgd_page_paddr(pgd_t pgd)
 {
-	return pgd_val(pgd) & PHYS_MASK & (s32)PAGE_MASK;
+	return __pgd_to_phys(pgd);
 }
 
 /* Find an entry in the frst-level page table. */
@@ -525,7 +551,7 @@ static inline phys_addr_t pgd_page_paddr(pgd_t pgd)
 #define pud_set_fixmap_offset(pgd, addr)	pud_set_fixmap(pud_offset_phys(pgd, addr))
 #define pud_clear_fixmap()		clear_fixmap(FIX_PUD)
 
-#define pgd_page(pgd)		pfn_to_page(__phys_to_pfn(pgd_val(pgd) & PHYS_MASK))
+#define pgd_page(pgd)		pfn_to_page(__phys_to_pfn(__pgd_to_phys(pgd)))
 
 /* use ONLY for statically allocated translation tables */
 #define pud_offset_kimg(dir,addr)	((pud_t *)__phys_to_kimg(pud_offset_phys((dir), (addr))))