2 * highmem.h: virtual kernel memory mappings for high memory
4 * Used in CONFIG_HIGHMEM systems for memory pages which
5 * are not addressable by direct kernel virtual addresses.
7 * Copyright (C) 1999 Gerhard Wichert, Siemens AG
8 * Gerhard.Wichert@pdb.siemens.de
11 * Redesigned the x86 32-bit VM architecture to deal with
12 * up to 16 Terabyte physical memory. With current x86 CPUs
13 * we now support up to 64 Gigabytes physical RAM.
15 * Copyright (C) 1999 Ingo Molnar <mingo@redhat.com>
18 #ifndef _ASM_X86_HIGHMEM_H
19 #define _ASM_X86_HIGHMEM_H
23 #include <linux/interrupt.h>
24 #include <linux/threads.h>
25 #include <asm/kmap_types.h>
26 #include <asm/tlbflush.h>
27 #include <asm/paravirt.h>
28 #include <asm/fixmap.h>
30 /* declarations for highmem.c */
31 extern unsigned long highstart_pfn
, highend_pfn
;
34 * Right now we initialize only a single pte table. It can be extended
35 * easily, subsequent pte tables have to be allocated in one physical
44 * temp fixed addresses
46 * Persistent kmap area
53 #define LAST_PKMAP_MASK (LAST_PKMAP-1)
54 #define PKMAP_NR(virt) ((virt-PKMAP_BASE) >> PAGE_SHIFT)
55 #define PKMAP_ADDR(nr) (PKMAP_BASE + ((nr) << PAGE_SHIFT))
57 extern void *kmap_high(struct page
*page
);
58 extern void kunmap_high(struct page
*page
);
60 void *kmap(struct page
*page
);
61 extern void kunmap_virt(void *ptr
);
62 extern struct page
*kmap_to_page(void *ptr
);
63 void kunmap(struct page
*page
);
65 void *__kmap_atomic_prot(struct page
*page
, enum km_type type
, pgprot_t prot
);
66 void *__kmap_atomic(struct page
*page
, enum km_type type
);
67 void *__kmap_atomic_direct(struct page
*page
, enum km_type type
);
68 void __kunmap_atomic(void *kvaddr
, enum km_type type
);
69 void *__kmap_atomic_pfn(unsigned long pfn
, enum km_type type
);
70 struct page
*__kmap_atomic_to_page(void *ptr
);
72 void kunmap(struct page
*page
);
73 void *kmap_atomic_prot(struct page
*page
, enum km_type type
, pgprot_t prot
);
74 void *kmap_atomic(struct page
*page
, enum km_type type
);
75 void kunmap_atomic(void *kvaddr
, enum km_type type
);
76 void *kmap_atomic_pfn(unsigned long pfn
, enum km_type type
);
77 void *kmap_atomic_prot_pfn(unsigned long pfn
, enum km_type type
, pgprot_t prot
);
78 struct page
*kmap_atomic_to_page(void *ptr
);
80 #ifndef CONFIG_PARAVIRT
81 #define kmap_atomic_pte(page, type) kmap_atomic(page, type)
82 #define kmap_atomic_pte_direct(page, type) kmap_atomic_direct(page, type)
85 #define flush_cache_kmaps() do { } while (0)
87 extern void add_highpages_with_active_regions(int nid
, unsigned long start_pfn
,
88 unsigned long end_pfn
);
91 * on PREEMPT_RT kmap_atomic() is a wrapper that uses kmap():
93 #ifdef CONFIG_PREEMPT_RT
94 # define kmap_atomic_prot(page, type, prot) ({ pagefault_disable(); kmap(page); })
95 # define kmap_atomic(page, type) ({ pagefault_disable(); kmap(page); })
96 # define kmap_atomic_pfn(pfn, type) kmap(pfn_to_page(pfn))
97 # define kunmap_atomic(kvaddr, type) do { pagefault_enable(); kunmap_virt(kvaddr); } while(0)
98 # define kmap_atomic_to_page(kvaddr) kmap_to_page(kvaddr)
99 # define kmap_atomic_direct(page, type) __kmap_atomic_direct(page, type)
100 # define kunmap_atomic_direct(kvaddr, type) __kunmap_atomic(kvaddr, type)
102 # define kmap_atomic_prot(page, type, prot) __kmap_atomic_prot(page, type, prot)
103 # define kmap_atomic(page, type) __kmap_atomic(page, type)
104 # define kmap_atomic_pfn(pfn, type) __kmap_atomic_pfn(pfn, type)
105 # define kunmap_atomic(kvaddr, type) __kunmap_atomic(kvaddr, type)
106 # define kmap_atomic_to_page(kvaddr) __kmap_atomic_to_page(kvaddr)
107 # define kmap_atomic_direct(page, type) __kmap_atomic(page, type)
108 # define kunmap_atomic_direct(kvaddr, type) __kunmap_atomic(kvaddr, type)
111 #endif /* __KERNEL__ */
113 #endif /* _ASM_X86_HIGHMEM_H */