From e4da9599c2af95edab2f1e6ae326f22f4afa99be Mon Sep 17 00:00:00 2001 From: Catalin Marinas Date: Mon, 31 Jan 2011 13:50:44 +0000 Subject: [PATCH] ARM: LPAE: Add identity mapping support for the 3-level page table format With LPAE, the pgd is a separate page table with entries pointing to the pmd. The identity_mapping_add() function needs to ensure that the pgd is populated before populating the pmd level. The do..while blocks now loop over the pmd in order to have the same implementation for the two page table formats. The pmd_addr_end() definition has been removed and the generic one used instead. The pmd clean-up is done in the pgd_free() function. Signed-off-by: Catalin Marinas --- arch/arm/include/asm/pgtable.h | 4 ---- arch/arm/mm/idmap.c | 36 ++++++++++++++++++++++++++++++++-- 2 files changed, 34 insertions(+), 6 deletions(-) diff --git a/arch/arm/include/asm/pgtable.h b/arch/arm/include/asm/pgtable.h index 1db9ad6decf0..9645e52f5585 100644 --- a/arch/arm/include/asm/pgtable.h +++ b/arch/arm/include/asm/pgtable.h @@ -263,10 +263,6 @@ static inline pte_t *pmd_page_vaddr(pmd_t pmd) #define pmd_page(pmd) pfn_to_page(__phys_to_pfn(pmd_val(pmd) & PHYS_MASK)) -/* we don't need complex calculations here as the pmd is folded into the pgd */ -#define pmd_addr_end(addr,end) (end) - - #ifndef CONFIG_HIGHPTE #define __pte_map(pmd) pmd_page_vaddr(*(pmd)) #define __pte_unmap(pte) do { } while (0) diff --git a/arch/arm/mm/idmap.c b/arch/arm/mm/idmap.c index 2be9139a4ef3..24e06555bee4 100644 --- a/arch/arm/mm/idmap.c +++ b/arch/arm/mm/idmap.c @@ -1,9 +1,36 @@ +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt + #include #include #include #include +#ifdef CONFIG_ARM_LPAE +static void idmap_add_pmd(pud_t *pud, unsigned long addr, unsigned long end, + unsigned long prot) +{ + pmd_t *pmd; + unsigned long next; + + if (pud_none_or_clear_bad(pud) || (pud_val(*pud) & L_PGD_SWAPPER)) { + pmd = pmd_alloc_one(NULL, addr); + if (!pmd) { + pr_warning("Failed to allocate identity pmd.\n"); + return; + } + pud_populate(NULL, pud, pmd); + pmd += pmd_index(addr); + } else + pmd = pmd_offset(pud, addr); + + do { + next = pmd_addr_end(addr, end); + *pmd = __pmd((addr & PMD_MASK) | prot); + flush_pmd_entry(pmd); + } while (pmd++, addr = next, addr != end); +} +#else /* !CONFIG_ARM_LPAE */ static void idmap_add_pmd(pud_t *pud, unsigned long addr, unsigned long end, unsigned long prot) { @@ -15,6 +42,7 @@ static void idmap_add_pmd(pud_t *pud, unsigned long addr, unsigned long end, pmd[1] = __pmd(addr); flush_pmd_entry(pmd); } +#endif /* CONFIG_ARM_LPAE */ static void idmap_add_pud(pgd_t *pgd, unsigned long addr, unsigned long end, unsigned long prot) @@ -32,7 +60,7 @@ void identity_mapping_add(pgd_t *pgd, unsigned long addr, unsigned long end) { unsigned long prot, next; - prot = PMD_TYPE_SECT | PMD_SECT_AP_WRITE; + prot = PMD_TYPE_SECT | PMD_SECT_AP_WRITE | PMD_SECT_AF; if (cpu_architecture() <= CPU_ARCH_ARMv5TEJ && !cpu_is_xscale()) prot |= PMD_BIT4; @@ -46,7 +74,11 @@ void identity_mapping_add(pgd_t *pgd, unsigned long addr, unsigned long end) #ifdef CONFIG_SMP static void idmap_del_pmd(pud_t *pud, unsigned long addr, unsigned long end) { - pmd_t *pmd = pmd_offset(pud, addr); + pmd_t *pmd; + + if (pud_none_or_clear_bad(pud)) + return; + pmd = pmd_offset(pud, addr); pmd_clear(pmd); } -- 2.39.5