Messages in this thread Patch in this message | | | From | Kees Cook <> | Subject | [PATCH 1/8] arm: use generic fixmap.h | Date | Thu, 7 Aug 2014 08:01:46 -0700 |
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From: Mark Salter <msalter@redhat.com>
ARM is different from other architectures in that fixmap pages are indexed with a positive offset from FIXADDR_START. Other architectures index with a negative offset from FIXADDR_TOP. In order to use the generic fixmap.h definitions, this patch redefines FIXADDR_TOP to be inclusive of the useable range. That is, FIXADDR_TOP is the virtual address of the topmost fixed page. The newly defined FIXADDR_END is the first virtual address past the fixed mappings.
Signed-off-by: Mark Salter <msalter@redhat.com> Reviewed-by: Doug Anderson <dianders@chromium.org> [update for "ARM: 8031/2: change fixmap mapping region to support 32 CPUs"] [flipped highmem order, thanks to Laura Abbott] Signed-off-by: Kees Cook <keescook@chromium.org> Cc: Laura Abbott <lauraa@codeaurora.org> --- arch/arm/include/asm/fixmap.h | 27 +++++++++------------------ arch/arm/mm/highmem.c | 8 ++++++-- arch/arm/mm/init.c | 2 +- 3 files changed, 16 insertions(+), 21 deletions(-)
diff --git a/arch/arm/include/asm/fixmap.h b/arch/arm/include/asm/fixmap.h index 74124b0d0d79..190142d174ee 100644 --- a/arch/arm/include/asm/fixmap.h +++ b/arch/arm/include/asm/fixmap.h @@ -2,27 +2,18 @@ #define _ASM_FIXMAP_H #define FIXADDR_START 0xffc00000UL -#define FIXADDR_TOP 0xffe00000UL -#define FIXADDR_SIZE (FIXADDR_TOP - FIXADDR_START) +#define FIXADDR_END 0xffe00000UL +#define FIXADDR_TOP (FIXADDR_END - PAGE_SIZE) +#define FIXADDR_SIZE (FIXADDR_END - FIXADDR_START) #define FIX_KMAP_NR_PTES (FIXADDR_SIZE >> PAGE_SHIFT) -#define __fix_to_virt(x) (FIXADDR_START + ((x) << PAGE_SHIFT)) -#define __virt_to_fix(x) (((x) - FIXADDR_START) >> PAGE_SHIFT) +enum fixed_addresses { + FIX_KMAP_BEGIN, + FIX_KMAP_END = FIX_KMAP_NR_PTES - 1, + __end_of_fixed_addresses +}; -extern void __this_fixmap_does_not_exist(void); - -static inline unsigned long fix_to_virt(const unsigned int idx) -{ - if (idx >= FIX_KMAP_NR_PTES) - __this_fixmap_does_not_exist(); - return __fix_to_virt(idx); -} - -static inline unsigned int virt_to_fix(const unsigned long vaddr) -{ - BUG_ON(vaddr >= FIXADDR_TOP || vaddr < FIXADDR_START); - return __virt_to_fix(vaddr); -} +#include <asm-generic/fixmap.h> #endif diff --git a/arch/arm/mm/highmem.c b/arch/arm/mm/highmem.c index 45aeaaca9052..a1241ee8425e 100644 --- a/arch/arm/mm/highmem.c +++ b/arch/arm/mm/highmem.c @@ -23,14 +23,18 @@ pte_t *fixmap_page_table; static inline void set_fixmap_pte(int idx, pte_t pte) { unsigned long vaddr = __fix_to_virt(idx); - set_pte_ext(fixmap_page_table + idx, pte, 0); + pte_t *ppte = pte_offset_kernel(pmd_off_k(FIXADDR_START), vaddr); + + set_pte_ext(ppte, pte, 0); local_flush_tlb_kernel_page(vaddr); } static inline pte_t get_fixmap_pte(unsigned long vaddr) { unsigned long idx = __virt_to_fix(vaddr); - return *(fixmap_page_table + idx); + pte_t *ppte = pte_offset_kernel(pmd_off_k(FIXADDR_START), vaddr); + + return *ppte; } void *kmap(struct page *page) diff --git a/arch/arm/mm/init.c b/arch/arm/mm/init.c index 659c75d808dc..ad82c05bfc3a 100644 --- a/arch/arm/mm/init.c +++ b/arch/arm/mm/init.c @@ -570,7 +570,7 @@ void __init mem_init(void) MLK(DTCM_OFFSET, (unsigned long) dtcm_end), MLK(ITCM_OFFSET, (unsigned long) itcm_end), #endif - MLK(FIXADDR_START, FIXADDR_TOP), + MLK(FIXADDR_START, FIXADDR_END), MLM(VMALLOC_START, VMALLOC_END), MLM(PAGE_OFFSET, (unsigned long)high_memory), #ifdef CONFIG_HIGHMEM -- 1.9.1
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