From da02877987e6e173ebba137d4e1e155e1f1151cd Mon Sep 17 00:00:00 2001 From: Catalin Marinas Date: Tue, 22 Nov 2011 17:30:29 +0000 Subject: [PATCH] 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 --- arch/arm/include/asm/pgalloc.h | 24 ++++++++++++ arch/arm/include/asm/pgtable-3level.h | 53 +++++++++++++++++++++++++++ arch/arm/include/asm/proc-fns.h | 21 +++++++++++ arch/arm/mm/ioremap.c | 8 ++-- arch/arm/mm/pgd.c | 51 ++++++++++++++++++++++++-- 5 files changed, 150 insertions(+), 7 deletions(-) diff --git a/arch/arm/include/asm/pgalloc.h b/arch/arm/include/asm/pgalloc.h index 7418894a737f..943504f53f57 100644 --- a/arch/arm/include/asm/pgalloc.h +++ b/arch/arm/include/asm/pgalloc.h @@ -25,6 +25,26 @@ #define _PAGE_USER_TABLE (PMD_TYPE_TABLE | PMD_BIT4 | PMD_DOMAIN(DOMAIN_USER)) #define _PAGE_KERNEL_TABLE (PMD_TYPE_TABLE | PMD_BIT4 | PMD_DOMAIN(DOMAIN_KERNEL)) +#ifdef CONFIG_ARM_LPAE + +static inline pmd_t *pmd_alloc_one(struct mm_struct *mm, unsigned long addr) +{ + return (pmd_t *)get_zeroed_page(GFP_KERNEL | __GFP_REPEAT); +} + +static inline void pmd_free(struct mm_struct *mm, pmd_t *pmd) +{ + BUG_ON((unsigned long)pmd & (PAGE_SIZE-1)); + free_page((unsigned long)pmd); +} + +static inline void pud_populate(struct mm_struct *mm, pud_t *pud, pmd_t *pmd) +{ + set_pud(pud, __pud(__pa(pmd) | PMD_TYPE_TABLE)); +} + +#else /* !CONFIG_ARM_LPAE */ + /* * Since we have only two-level page tables, these are trivial */ @@ -32,6 +52,8 @@ #define pmd_free(mm, pmd) do { } while (0) #define pud_populate(mm,pmd,pte) BUG() +#endif /* CONFIG_ARM_LPAE */ + extern pgd_t *pgd_alloc(struct mm_struct *mm); extern void pgd_free(struct mm_struct *mm, pgd_t *pgd); @@ -109,7 +131,9 @@ static inline void __pmd_populate(pmd_t *pmdp, phys_addr_t pte, { pmdval_t pmdval = (pte + PTE_HWTABLE_OFF) | prot; pmdp[0] = __pmd(pmdval); +#ifndef CONFIG_ARM_LPAE pmdp[1] = __pmd(pmdval + 256 * sizeof(pte_t)); +#endif flush_pmd_entry(pmdp); } diff --git a/arch/arm/include/asm/pgtable-3level.h b/arch/arm/include/asm/pgtable-3level.h index 79bf0acc40db..759af70f9a0a 100644 --- a/arch/arm/include/asm/pgtable-3level.h +++ b/arch/arm/include/asm/pgtable-3level.h @@ -99,4 +99,57 @@ #define L_PTE_MT_DEV_CACHED (_AT(pteval_t, 3) << 2) /* normal inner write-back */ #define L_PTE_MT_MASK (_AT(pteval_t, 7) << 2) +/* + * Software PGD flags. + */ +#define L_PGD_SWAPPER (_AT(pgdval_t, 1) << 55) /* swapper_pg_dir entry */ + +#ifndef __ASSEMBLY__ + +#define pud_none(pud) (!pud_val(pud)) +#define pud_bad(pud) (!(pud_val(pud) & 2)) +#define pud_present(pud) (pud_val(pud)) + +#define pud_clear(pudp) \ + do { \ + *pudp = __pud(0); \ + clean_pmd_entry(pudp); \ + } while (0) + +#define set_pud(pudp, pud) \ + do { \ + *pudp = pud; \ + flush_pmd_entry(pudp); \ + } while (0) + +static inline pmd_t *pud_page_vaddr(pud_t pud) +{ + return __va(pud_val(pud) & PHYS_MASK & (s32)PAGE_MASK); +} + +/* Find an entry in the second-level page table.. */ +#define pmd_index(addr) (((addr) >> PMD_SHIFT) & (PTRS_PER_PMD - 1)) +static inline pmd_t *pmd_offset(pud_t *pud, unsigned long addr) +{ + return (pmd_t *)pud_page_vaddr(*pud) + pmd_index(addr); +} + +#define pmd_bad(pmd) (!(pmd_val(pmd) & 2)) + +#define copy_pmd(pmdpd,pmdps) \ + do { \ + *pmdpd = *pmdps; \ + flush_pmd_entry(pmdpd); \ + } while (0) + +#define pmd_clear(pmdp) \ + do { \ + *pmdp = __pmd(0); \ + clean_pmd_entry(pmdp); \ + } while (0) + +#define set_pte_ext(ptep,pte,ext) cpu_set_pte_ext(ptep,__pte(pte_val(pte)|(ext))) + +#endif /* __ASSEMBLY__ */ + #endif /* _ASM_PGTABLE_3LEVEL_H */ 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 diff --git a/arch/arm/mm/ioremap.c b/arch/arm/mm/ioremap.c index c3fa40da3b75..d1f78bacb015 100644 --- a/arch/arm/mm/ioremap.c +++ b/arch/arm/mm/ioremap.c @@ -64,7 +64,7 @@ void __check_kvm_seq(struct mm_struct *mm) } while (seq != init_mm.context.kvm_seq); } -#ifndef CONFIG_SMP +#if !defined(CONFIG_SMP) && !defined(CONFIG_ARM_LPAE) /* * Section support is unsafe on SMP - If you iounmap and ioremap a region, * the other CPUs will not see this change until their next context switch. @@ -202,11 +202,13 @@ void __iomem * __arm_ioremap_pfn_caller(unsigned long pfn, unsigned long addr; struct vm_struct * area; +#ifndef CONFIG_ARM_LPAE /* * High mappings must be supersection aligned */ if (pfn >= 0x100000 && (__pfn_to_phys(pfn) & ~SUPERSECTION_MASK)) return NULL; +#endif /* * Don't allow RAM to be mapped - this causes problems with ARMv6+ @@ -228,7 +230,7 @@ void __iomem * __arm_ioremap_pfn_caller(unsigned long pfn, return NULL; addr = (unsigned long)area->addr; -#ifndef CONFIG_SMP +#if !defined(CONFIG_SMP) && !defined(CONFIG_ARM_LPAE) if (DOMAIN_IO == 0 && (((cpu_architecture() >= CPU_ARCH_ARMv6) && (get_cr() & CR_XP)) || cpu_is_xsc3()) && pfn >= 0x100000 && @@ -320,7 +322,7 @@ __arm_ioremap_exec(unsigned long phys_addr, size_t size, bool cached) void __iounmap(volatile void __iomem *io_addr) { void *addr = (void *)(PAGE_MASK & (unsigned long)io_addr); -#ifndef CONFIG_SMP +#if !defined(CONFIG_SMP) && !defined(CONFIG_ARM_LPAE) struct vm_struct **p, *tmp; /* diff --git a/arch/arm/mm/pgd.c b/arch/arm/mm/pgd.c index b2027c154b2a..a3e78ccabd65 100644 --- a/arch/arm/mm/pgd.c +++ b/arch/arm/mm/pgd.c @@ -10,6 +10,7 @@ #include #include #include +#include #include #include @@ -17,6 +18,14 @@ #include "mm.h" +#ifdef CONFIG_ARM_LPAE +#define __pgd_alloc() kmalloc(PTRS_PER_PGD * sizeof(pgd_t), GFP_KERNEL) +#define __pgd_free(pgd) kfree(pgd) +#else +#define __pgd_alloc() (pgd_t *)__get_free_pages(GFP_KERNEL, 2) +#define __pgd_free(pgd) free_pages((unsigned long)pgd, 2) +#endif + /* * need to get a 16k page for level 1 */ @@ -27,7 +36,7 @@ pgd_t *pgd_alloc(struct mm_struct *mm) pmd_t *new_pmd, *init_pmd; pte_t *new_pte, *init_pte; - new_pgd = (pgd_t *)__get_free_pages(GFP_KERNEL, 2); + new_pgd = __pgd_alloc(); if (!new_pgd) goto no_pgd; @@ -42,10 +51,25 @@ pgd_t *pgd_alloc(struct mm_struct *mm) clean_dcache_area(new_pgd, PTRS_PER_PGD * sizeof(pgd_t)); +#ifdef CONFIG_ARM_LPAE + /* + * Allocate PMD table for modules and pkmap mappings. + */ + new_pud = pud_alloc(mm, new_pgd + pgd_index(MODULES_VADDR), + MODULES_VADDR); + if (!new_pud) + goto no_pud; + + new_pmd = pmd_alloc(mm, new_pud, 0); + if (!new_pmd) + goto no_pmd; +#endif + if (!vectors_high()) { /* * On ARM, first page must always be allocated since it - * contains the machine vectors. + * contains the machine vectors. The vectors are always high + * with LPAE. */ new_pud = pud_alloc(mm, new_pgd, 0); if (!new_pud) @@ -74,7 +98,7 @@ no_pte: no_pmd: pud_free(mm, new_pud); no_pud: - free_pages((unsigned long)new_pgd, 2); + __pgd_free(new_pgd); no_pgd: return NULL; } @@ -111,5 +135,24 @@ no_pud: pgd_clear(pgd); pud_free(mm, pud); no_pgd: - free_pages((unsigned long) pgd_base, 2); +#ifdef CONFIG_ARM_LPAE + /* + * Free modules/pkmap or identity pmd tables. + */ + for (pgd = pgd_base; pgd < pgd_base + PTRS_PER_PGD; pgd++) { + if (pgd_none_or_clear_bad(pgd)) + continue; + if (pgd_val(*pgd) & L_PGD_SWAPPER) + continue; + pud = pud_offset(pgd, 0); + if (pud_none_or_clear_bad(pud)) + continue; + pmd = pmd_offset(pud, 0); + pud_clear(pud); + pmd_free(mm, pmd); + pgd_clear(pgd); + pud_free(mm, pud); + } +#endif + __pgd_free(pgd_base); } -- 2.30.2