| Message ID | 1407867869-5194-2-git-send-email-keescook@chromium.org (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Tue, Aug 12, 2014 at 11:24 AM, Kees Cook <keescook@chromium.org> wrote: > 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> > [kees: update for a05e54c103b0b8 "ARM: 8031/2: change fixmap ..."] > [kees: fixed highmem usage, thanks to Laura Abbott and Rob Herring] > Signed-off-by: Kees Cook <keescook@chromium.org> > Cc: Laura Abbott <lauraa@codeaurora.org> > Cc: Rob Herring <robh@kernel.org> > --- > arch/arm/include/asm/fixmap.h | 27 +++++++++------------------ > arch/arm/include/asm/highmem.h | 1 - > arch/arm/mm/highmem.c | 15 ++++++++------- > arch/arm/mm/init.c | 2 +- > arch/arm/mm/mmu.c | 6 +++--- > 5 files changed, 21 insertions(+), 30 deletions(-) > > diff --git a/arch/arm/include/asm/fixmap.h b/arch/arm/include/asm/fixmap.h > index 74124b0d0d79..a7add6f9315d 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 FIX_KMAP_NR_PTES (FIXADDR_SIZE >> PAGE_SHIFT) > +#include <asm/kmap_types.h> > > -#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_BEGIN + (KM_TYPE_NR * NR_CPUS) - 1, > > -extern void __this_fixmap_does_not_exist(void); > + __end_of_fixed_addresses > +}; > > -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/include/asm/highmem.h b/arch/arm/include/asm/highmem.h > index 535579511ed0..91b99abe7a95 100644 > --- a/arch/arm/include/asm/highmem.h > +++ b/arch/arm/include/asm/highmem.h > @@ -18,7 +18,6 @@ > } while (0) > > extern pte_t *pkmap_page_table; > -extern pte_t *fixmap_page_table; > > extern void *kmap_high(struct page *page); > extern void kunmap_high(struct page *page); > diff --git a/arch/arm/mm/highmem.c b/arch/arm/mm/highmem.c > index 45aeaaca9052..f87e0b89b738 100644 > --- a/arch/arm/mm/highmem.c > +++ b/arch/arm/mm/highmem.c > @@ -18,19 +18,20 @@ > #include <asm/tlbflush.h> > #include "mm.h" > > -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) > @@ -84,7 +85,7 @@ void *kmap_atomic(struct page *page) > * With debugging enabled, kunmap_atomic forces that entry to 0. > * Make sure it was indeed properly unmapped. > */ > - BUG_ON(!pte_none(*(fixmap_page_table + idx))); > + BUG_ON(!pte_none(*get_fixmap_pte(vaddr))); > #endif Buildbot noticed that with CONFIG_DEBUG_HIGHMEM, this and the next instance shouldn't have the leading "*" in front of the get_fixmap_pte call. I've fixed that in my tree. > /* > * When debugging is off, kunmap_atomic leaves the previous mapping > @@ -134,7 +135,7 @@ void *kmap_atomic_pfn(unsigned long pfn) > idx = type + KM_TYPE_NR * smp_processor_id(); > vaddr = __fix_to_virt(idx); > #ifdef CONFIG_DEBUG_HIGHMEM > - BUG_ON(!pte_none(*(fixmap_page_table + idx))); > + BUG_ON(!pte_none(*get_fixmap_pte(vaddr))); > #endif Here too, as above. -Kees > set_fixmap_pte(idx, pfn_pte(pfn, kmap_prot)); > > 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 > diff --git a/arch/arm/mm/mmu.c b/arch/arm/mm/mmu.c > index 8348ed6b2efe..7fa0966cd15f 100644 > --- a/arch/arm/mm/mmu.c > +++ b/arch/arm/mm/mmu.c > @@ -1326,10 +1326,10 @@ static void __init kmap_init(void) > #ifdef CONFIG_HIGHMEM > pkmap_page_table = early_pte_alloc(pmd_off_k(PKMAP_BASE), > PKMAP_BASE, _PAGE_KERNEL_TABLE); > - > - fixmap_page_table = early_pte_alloc(pmd_off_k(FIXADDR_START), > - FIXADDR_START, _PAGE_KERNEL_TABLE); > #endif > + > + early_pte_alloc(pmd_off_k(FIXADDR_START), FIXADDR_START, > + _PAGE_KERNEL_TABLE); > } > > static void __init map_lowmem(void) > -- > 1.9.1 >
diff --git a/arch/arm/include/asm/fixmap.h b/arch/arm/include/asm/fixmap.h index 74124b0d0d79..a7add6f9315d 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 FIX_KMAP_NR_PTES (FIXADDR_SIZE >> PAGE_SHIFT) +#include <asm/kmap_types.h> -#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_BEGIN + (KM_TYPE_NR * NR_CPUS) - 1, -extern void __this_fixmap_does_not_exist(void); + __end_of_fixed_addresses +}; -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/include/asm/highmem.h b/arch/arm/include/asm/highmem.h index 535579511ed0..91b99abe7a95 100644 --- a/arch/arm/include/asm/highmem.h +++ b/arch/arm/include/asm/highmem.h @@ -18,7 +18,6 @@ } while (0) extern pte_t *pkmap_page_table; -extern pte_t *fixmap_page_table; extern void *kmap_high(struct page *page); extern void kunmap_high(struct page *page); diff --git a/arch/arm/mm/highmem.c b/arch/arm/mm/highmem.c index 45aeaaca9052..f87e0b89b738 100644 --- a/arch/arm/mm/highmem.c +++ b/arch/arm/mm/highmem.c @@ -18,19 +18,20 @@ #include <asm/tlbflush.h> #include "mm.h" -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) @@ -84,7 +85,7 @@ void *kmap_atomic(struct page *page) * With debugging enabled, kunmap_atomic forces that entry to 0. * Make sure it was indeed properly unmapped. */ - BUG_ON(!pte_none(*(fixmap_page_table + idx))); + BUG_ON(!pte_none(*get_fixmap_pte(vaddr))); #endif /* * When debugging is off, kunmap_atomic leaves the previous mapping @@ -134,7 +135,7 @@ void *kmap_atomic_pfn(unsigned long pfn) idx = type + KM_TYPE_NR * smp_processor_id(); vaddr = __fix_to_virt(idx); #ifdef CONFIG_DEBUG_HIGHMEM - BUG_ON(!pte_none(*(fixmap_page_table + idx))); + BUG_ON(!pte_none(*get_fixmap_pte(vaddr))); #endif set_fixmap_pte(idx, pfn_pte(pfn, kmap_prot)); 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 diff --git a/arch/arm/mm/mmu.c b/arch/arm/mm/mmu.c index 8348ed6b2efe..7fa0966cd15f 100644 --- a/arch/arm/mm/mmu.c +++ b/arch/arm/mm/mmu.c @@ -1326,10 +1326,10 @@ static void __init kmap_init(void) #ifdef CONFIG_HIGHMEM pkmap_page_table = early_pte_alloc(pmd_off_k(PKMAP_BASE), PKMAP_BASE, _PAGE_KERNEL_TABLE); - - fixmap_page_table = early_pte_alloc(pmd_off_k(FIXADDR_START), - FIXADDR_START, _PAGE_KERNEL_TABLE); #endif + + early_pte_alloc(pmd_off_k(FIXADDR_START), FIXADDR_START, + _PAGE_KERNEL_TABLE); } static void __init map_lowmem(void)