ARM: LPAE: Page table maintenance for the 3-level format

This patch modifies the pgd/pmd/pte manipulation functions to support
the 3-level page table format. Since there is no need for an 'ext'
argument to cpu_set_pte_ext(), this patch conditionally defines a
different prototype for this function when CONFIG_ARM_LPAE.

The patch also introduces the L_PGD_SWAPPER flag to mark pgd entries
pointing to pmd tables pre-allocated in the swapper_pg_dir and avoid
trying to free them at run-time. This flag is 0 with the classic page
table format.

Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>

1 files changed, 21 insertions, 0 deletions

diff --git a/arch/arm/include/asm/proc-fns.h b/arch/arm/include/asm/proc-fns.h
index 9e92cb205e65..f3628fb3d2b3 100644
--- a/arch/arm/include/asm/proc-fns.h
+++ b/arch/arm/include/asm/proc-fns.h
@@ -65,7 +65,11 @@ extern struct processor {
          * Set a possibly extended PTE.  Non-extended PTEs should
          * ignore 'ext'.
          */
+#ifdef CONFIG_ARM_LPAE
+        void (*set_pte_ext)(pte_t *ptep, pte_t pte);
+#else
         void (*set_pte_ext)(pte_t *ptep, pte_t pte, unsigned int ext);
+#endif
 
         /* Suspend/resume */
         unsigned int suspend_size;
@@ -79,7 +83,11 @@ extern void cpu_proc_fin(void);
 extern int cpu_do_idle(void);
 extern void cpu_dcache_clean_area(void *, int);
 extern void cpu_do_switch_mm(unsigned long pgd_phys, struct mm_struct *mm);
+#ifdef CONFIG_ARM_LPAE
+extern void cpu_set_pte_ext(pte_t *ptep, pte_t pte);
+#else
 extern void cpu_set_pte_ext(pte_t *ptep, pte_t pte, unsigned int ext);
+#endif
 extern void cpu_reset(unsigned long addr) __attribute__((noreturn));
 
 /* These three are private to arch/arm/kernel/suspend.c */
@@ -107,6 +115,18 @@ extern void cpu_resume(void);
 
 #define cpu_switch_mm(pgd,mm) cpu_do_switch_mm(virt_to_phys(pgd),mm)
 
+#ifdef CONFIG_ARM_LPAE
+#define cpu_get_pgd()   \
+        ({                                              \
+                unsigned long pg, pg2;                  \
+                __asm__("mrrc   p15, 0, %0, %1, c2"     \
+                        : "=r" (pg), "=r" (pg2)         \
+                        :                               \
+                        : "cc");                        \
+                pg &= ~(PTRS_PER_PGD*sizeof(pgd_t)-1);  \
+                (pgd_t *)phys_to_virt(pg);              \
+        })
+#else
 #define cpu_get_pgd()   \
         ({                                              \
                 unsigned long pg;                       \
@@ -115,6 +135,7 @@ extern void cpu_resume(void);
                 pg &= ~0x3fff;                          \
                 (pgd_t *)phys_to_virt(pg);              \
         })
+#endif
 
 #endif