From 778d03a089c7cc31c5d3f983ecd18704d287fa0e Mon Sep 17 00:00:00 2001 From: "iap10@labyrinth.cl.cam.ac.uk" Date: Thu, 15 Apr 2004 15:55:59 +0000 Subject: bitkeeper revision 1.864.1.1 (407eb08fW2eUAKOIh6v4T-Ew4bCchg) upgrade to linux 2.4.26 --- xenolinux-2.4.26-sparse/include/asm-xen/highmem.h | 132 ++++++++++++++++++++++ 1 file changed, 132 insertions(+) create mode 100644 xenolinux-2.4.26-sparse/include/asm-xen/highmem.h (limited to 'xenolinux-2.4.26-sparse/include/asm-xen/highmem.h') diff --git a/xenolinux-2.4.26-sparse/include/asm-xen/highmem.h b/xenolinux-2.4.26-sparse/include/asm-xen/highmem.h new file mode 100644 index 0000000000..25ef32882c --- /dev/null +++ b/xenolinux-2.4.26-sparse/include/asm-xen/highmem.h @@ -0,0 +1,132 @@ +/* + * highmem.h: virtual kernel memory mappings for high memory + * + * Used in CONFIG_HIGHMEM systems for memory pages which + * are not addressable by direct kernel virtual addresses. + * + * Copyright (C) 1999 Gerhard Wichert, Siemens AG + * Gerhard.Wichert@pdb.siemens.de + * + * + * Redesigned the x86 32-bit VM architecture to deal with + * up to 16 Terabyte physical memory. With current x86 CPUs + * we now support up to 64 Gigabytes physical RAM. + * + * Copyright (C) 1999 Ingo Molnar + */ + +#ifndef _ASM_HIGHMEM_H +#define _ASM_HIGHMEM_H + +#ifdef __KERNEL__ + +#include +#include +#include +#include +#include + +#ifdef CONFIG_DEBUG_HIGHMEM +#define HIGHMEM_DEBUG 1 +#else +#define HIGHMEM_DEBUG 0 +#endif + +/* declarations for highmem.c */ +extern unsigned long highstart_pfn, highend_pfn; + +extern pte_t *kmap_pte; +extern pgprot_t kmap_prot; +extern pte_t *pkmap_page_table; + +extern void kmap_init(void) __init; + +/* + * Right now we initialize only a single pte table. It can be extended + * easily, subsequent pte tables have to be allocated in one physical + * chunk of RAM. + */ +#define PKMAP_BASE (HYPERVISOR_VIRT_START - (1<<23)) +#ifdef CONFIG_X86_PAE +#define LAST_PKMAP 512 +#else +#define LAST_PKMAP 1024 +#endif +#define LAST_PKMAP_MASK (LAST_PKMAP-1) +#define PKMAP_NR(virt) ((virt-PKMAP_BASE) >> PAGE_SHIFT) +#define PKMAP_ADDR(nr) (PKMAP_BASE + ((nr) << PAGE_SHIFT)) + +extern void * FASTCALL(kmap_high(struct page *page, int nonblocking)); +extern void FASTCALL(kunmap_high(struct page *page)); + +#define kmap(page) __kmap(page, 0) +#define kmap_nonblock(page) __kmap(page, 1) + +static inline void *__kmap(struct page *page, int nonblocking) +{ + if (in_interrupt()) + out_of_line_bug(); + if (page < highmem_start_page) + return page_address(page); + return kmap_high(page, nonblocking); +} + +static inline void kunmap(struct page *page) +{ + if (in_interrupt()) + out_of_line_bug(); + if (page < highmem_start_page) + return; + kunmap_high(page); +} + +/* + * The use of kmap_atomic/kunmap_atomic is discouraged - kmap/kunmap + * gives a more generic (and caching) interface. But kmap_atomic can + * 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) +{ + enum fixed_addresses idx; + unsigned long vaddr; + + if (page < highmem_start_page) + return page_address(page); + + idx = type + KM_TYPE_NR*smp_processor_id(); + vaddr = __fix_to_virt(FIX_KMAP_BEGIN + idx); +#if HIGHMEM_DEBUG + if (!pte_none(*(kmap_pte-idx))) + out_of_line_bug(); +#endif + set_pte(kmap_pte-idx, mk_pte(page, kmap_prot)); + __flush_tlb_one(vaddr); + + return (void*) vaddr; +} + +static inline void kunmap_atomic(void *kvaddr, enum km_type type) +{ +#if HIGHMEM_DEBUG + unsigned long vaddr = (unsigned long) kvaddr & PAGE_MASK; + enum fixed_addresses idx = type + KM_TYPE_NR*smp_processor_id(); + + if (vaddr < FIXADDR_START) // FIXME + return; + + if (vaddr != __fix_to_virt(FIX_KMAP_BEGIN+idx)) + out_of_line_bug(); + + /* + * force other mappings to Oops if they'll try to access + * this pte without first remap it + */ + pte_clear(kmap_pte-idx); + __flush_tlb_one(vaddr); +#endif +} + +#endif /* __KERNEL__ */ + +#endif /* _ASM_HIGHMEM_H */ -- cgit v1.2.3