xref: /openbmc/linux/arch/x86/include/asm/pgtable_32.h (revision 293d5b43)
1 #ifndef _ASM_X86_PGTABLE_32_H
2 #define _ASM_X86_PGTABLE_32_H
3 
4 #include <asm/pgtable_32_types.h>
5 
6 /*
7  * The Linux memory management assumes a three-level page table setup. On
8  * the i386, we use that, but "fold" the mid level into the top-level page
9  * table, so that we physically have the same two-level page table as the
10  * i386 mmu expects.
11  *
12  * This file contains the functions and defines necessary to modify and use
13  * the i386 page table tree.
14  */
15 #ifndef __ASSEMBLY__
16 #include <asm/processor.h>
17 #include <asm/fixmap.h>
18 #include <linux/threads.h>
19 #include <asm/paravirt.h>
20 
21 #include <linux/bitops.h>
22 #include <linux/list.h>
23 #include <linux/spinlock.h>
24 
25 struct mm_struct;
26 struct vm_area_struct;
27 
28 extern pgd_t swapper_pg_dir[1024];
29 extern pgd_t initial_page_table[1024];
30 
31 static inline void pgtable_cache_init(void) { }
32 static inline void check_pgt_cache(void) { }
33 void paging_init(void);
34 
35 /*
36  * Define this if things work differently on an i386 and an i486:
37  * it will (on an i486) warn about kernel memory accesses that are
38  * done without a 'access_ok(VERIFY_WRITE,..)'
39  */
40 #undef TEST_ACCESS_OK
41 
42 #ifdef CONFIG_X86_PAE
43 # include <asm/pgtable-3level.h>
44 #else
45 # include <asm/pgtable-2level.h>
46 #endif
47 
48 #if defined(CONFIG_HIGHPTE)
49 #define pte_offset_map(dir, address)					\
50 	((pte_t *)kmap_atomic(pmd_page(*(dir))) +		\
51 	 pte_index((address)))
52 #define pte_unmap(pte) kunmap_atomic((pte))
53 #else
54 #define pte_offset_map(dir, address)					\
55 	((pte_t *)page_address(pmd_page(*(dir))) + pte_index((address)))
56 #define pte_unmap(pte) do { } while (0)
57 #endif
58 
59 /* Clear a kernel PTE and flush it from the TLB */
60 #define kpte_clear_flush(ptep, vaddr)		\
61 do {						\
62 	pte_clear(&init_mm, (vaddr), (ptep));	\
63 	__flush_tlb_one((vaddr));		\
64 } while (0)
65 
66 #endif /* !__ASSEMBLY__ */
67 
68 /*
69  * kern_addr_valid() is (1) for FLATMEM and (0) for
70  * SPARSEMEM and DISCONTIGMEM
71  */
72 #ifdef CONFIG_FLATMEM
73 #define kern_addr_valid(addr)	(1)
74 #else
75 #define kern_addr_valid(kaddr)	(0)
76 #endif
77 
78 #endif /* _ASM_X86_PGTABLE_32_H */
79