diff options
Diffstat (limited to 'include/asm-powerpc')
| -rw-r--r-- | include/asm-powerpc/fixmap.h | 106 | ||||
| -rw-r--r-- | include/asm-powerpc/highmem.h | 41 |
2 files changed, 128 insertions, 19 deletions
diff --git a/include/asm-powerpc/fixmap.h b/include/asm-powerpc/fixmap.h new file mode 100644 index 000000000000..8428b38a3d30 --- /dev/null +++ b/include/asm-powerpc/fixmap.h @@ -0,0 +1,106 @@ +/* + * fixmap.h: compile-time virtual memory allocation + * + * This file is subject to the terms and conditions of the GNU General Public + * License. See the file "COPYING" in the main directory of this archive + * for more details. + * + * Copyright (C) 1998 Ingo Molnar + * + * Copyright 2008 Freescale Semiconductor Inc. + * Port to powerpc added by Kumar Gala + */ + +#ifndef _ASM_FIXMAP_H +#define _ASM_FIXMAP_H + +extern unsigned long FIXADDR_TOP; + +#ifndef __ASSEMBLY__ +#include <linux/kernel.h> +#include <asm/page.h> +#ifdef CONFIG_HIGHMEM +#include <linux/threads.h> +#include <asm/kmap_types.h> +#endif + +/* + * Here we define all the compile-time 'special' virtual + * addresses. The point is to have a constant address at + * compile time, but to set the physical address only + * in the boot process. We allocate these special addresses + * from the end of virtual memory (0xfffff000) backwards. + * Also this lets us do fail-safe vmalloc(), we + * can guarantee that these special addresses and + * vmalloc()-ed addresses never overlap. + * + * these 'compile-time allocated' memory buffers are + * fixed-size 4k pages. (or larger if used with an increment + * highger than 1) use fixmap_set(idx,phys) to associate + * physical memory with fixmap indices. + * + * TLB entries of such buffers will not be flushed across + * task switches. + */ +enum fixed_addresses { + FIX_HOLE, +#ifdef CONFIG_HIGHMEM + FIX_KMAP_BEGIN, /* reserved pte's for temporary kernel mappings */ + FIX_KMAP_END = FIX_KMAP_BEGIN+(KM_TYPE_NR*NR_CPUS)-1, +#endif + /* FIX_PCIE_MCFG, */ + __end_of_fixed_addresses +}; + +extern void __set_fixmap (enum fixed_addresses idx, + phys_addr_t phys, pgprot_t flags); + +#define set_fixmap(idx, phys) \ + __set_fixmap(idx, phys, PAGE_KERNEL) +/* + * Some hardware wants to get fixmapped without caching. + */ +#define set_fixmap_nocache(idx, phys) \ + __set_fixmap(idx, phys, PAGE_KERNEL_NOCACHE) + +#define clear_fixmap(idx) \ + __set_fixmap(idx, 0, __pgprot(0)) + +#define __FIXADDR_SIZE (__end_of_fixed_addresses << PAGE_SHIFT) +#define FIXADDR_START (FIXADDR_TOP - __FIXADDR_SIZE) + +#define __fix_to_virt(x) (FIXADDR_TOP - ((x) << PAGE_SHIFT)) +#define __virt_to_fix(x) ((FIXADDR_TOP - ((x)&PAGE_MASK)) >> PAGE_SHIFT) + +extern void __this_fixmap_does_not_exist(void); + +/* + * 'index to address' translation. If anyone tries to use the idx + * directly without tranlation, we catch the bug with a NULL-deference + * kernel oops. Illegal ranges of incoming indices are caught too. + */ +static __always_inline unsigned long fix_to_virt(const unsigned int idx) +{ + /* + * this branch gets completely eliminated after inlining, + * except when someone tries to use fixaddr indices in an + * illegal way. (such as mixing up address types or using + * out-of-range indices). + * + * If it doesn't get removed, the linker will complain + * loudly with a reasonably clear error message.. + */ + if (idx >= __end_of_fixed_addresses) + __this_fixmap_does_not_exist(); + + return __fix_to_virt(idx); +} + +static inline unsigned long virt_to_fix(const unsigned long vaddr) +{ + BUG_ON(vaddr >= FIXADDR_TOP || vaddr < FIXADDR_START); + return __virt_to_fix(vaddr); +} + +#endif /* !__ASSEMBLY__ */ +#endif diff --git a/include/asm-powerpc/highmem.h b/include/asm-powerpc/highmem.h index f7b21ee302b4..5d99b6489d56 100644 --- a/include/asm-powerpc/highmem.h +++ b/include/asm-powerpc/highmem.h @@ -27,9 +27,7 @@ #include <asm/kmap_types.h> #include <asm/tlbflush.h> #include <asm/page.h> - -/* undef for production */ -#define HIGHMEM_DEBUG 1 +#include <asm/fixmap.h> extern pte_t *kmap_pte; extern pgprot_t kmap_prot; @@ -40,14 +38,12 @@ extern pte_t *pkmap_page_table; * easily, subsequent pte tables have to be allocated in one physical * chunk of RAM. */ -#define PKMAP_BASE CONFIG_HIGHMEM_START #define LAST_PKMAP (1 << PTE_SHIFT) #define LAST_PKMAP_MASK (LAST_PKMAP-1) +#define PKMAP_BASE ((FIXADDR_START - PAGE_SIZE*(LAST_PKMAP + 1)) & PMD_MASK) #define PKMAP_NR(virt) ((virt-PKMAP_BASE) >> PAGE_SHIFT) #define PKMAP_ADDR(nr) (PKMAP_BASE + ((nr) << PAGE_SHIFT)) -#define KMAP_FIX_BEGIN (PKMAP_BASE + 0x00400000UL) - extern void *kmap_high(struct page *page); extern void kunmap_high(struct page *page); @@ -73,7 +69,7 @@ static inline void kunmap(struct page *page) * be used in IRQ contexts, so in some (very limited) cases we need * it. */ -static inline void *kmap_atomic(struct page *page, enum km_type type) +static inline void *kmap_atomic_prot(struct page *page, enum km_type type, pgprot_t prot) { unsigned int idx; unsigned long vaddr; @@ -84,34 +80,39 @@ static inline void *kmap_atomic(struct page *page, enum km_type type) return page_address(page); idx = type + KM_TYPE_NR*smp_processor_id(); - vaddr = KMAP_FIX_BEGIN + idx * PAGE_SIZE; -#ifdef HIGHMEM_DEBUG - BUG_ON(!pte_none(*(kmap_pte+idx))); + vaddr = __fix_to_virt(FIX_KMAP_BEGIN + idx); +#ifdef CONFIG_DEBUG_HIGHMEM + BUG_ON(!pte_none(*(kmap_pte-idx))); #endif - set_pte_at(&init_mm, vaddr, kmap_pte+idx, mk_pte(page, kmap_prot)); + set_pte_at(&init_mm, vaddr, kmap_pte-idx, mk_pte(page, prot)); flush_tlb_page(NULL, vaddr); return (void*) vaddr; } +static inline void *kmap_atomic(struct page *page, enum km_type type) +{ + return kmap_atomic_prot(page, type, kmap_prot); +} + static inline void kunmap_atomic(void *kvaddr, enum km_type type) { -#ifdef HIGHMEM_DEBUG +#ifdef CONFIG_DEBUG_HIGHMEM unsigned long vaddr = (unsigned long) kvaddr & PAGE_MASK; - unsigned int idx = type + KM_TYPE_NR*smp_processor_id(); + enum fixed_addresses idx = type + KM_TYPE_NR*smp_processor_id(); - if (vaddr < KMAP_FIX_BEGIN) { // FIXME + if (vaddr < __fix_to_virt(FIX_KMAP_END)) { pagefault_enable(); return; } - BUG_ON(vaddr != KMAP_FIX_BEGIN + idx * PAGE_SIZE); + BUG_ON(vaddr != __fix_to_virt(FIX_KMAP_BEGIN + idx)); /* * force other mappings to Oops if they'll try to access * this pte without first remap it */ - pte_clear(&init_mm, vaddr, kmap_pte+idx); + pte_clear(&init_mm, vaddr, kmap_pte-idx); flush_tlb_page(NULL, vaddr); #endif pagefault_enable(); @@ -120,12 +121,14 @@ static inline void kunmap_atomic(void *kvaddr, enum km_type type) static inline struct page *kmap_atomic_to_page(void *ptr) { unsigned long idx, vaddr = (unsigned long) ptr; + pte_t *pte; - if (vaddr < KMAP_FIX_BEGIN) + if (vaddr < FIXADDR_START) return virt_to_page(ptr); - idx = (vaddr - KMAP_FIX_BEGIN) >> PAGE_SHIFT; - return pte_page(kmap_pte[idx]); + idx = virt_to_fix(vaddr); + pte = kmap_pte - (idx - FIX_KMAP_BEGIN); + return pte_page(*pte); } #define flush_cache_kmaps() flush_cache_all() |