xref: /openbmc/linux/arch/arm64/include/asm/page.h (revision 0da85d1e)
1 /*
2  * Based on arch/arm/include/asm/page.h
3  *
4  * Copyright (C) 1995-2003 Russell King
5  * Copyright (C) 2012 ARM Ltd.
6  *
7  * This program is free software; you can redistribute it and/or modify
8  * it under the terms of the GNU General Public License version 2 as
9  * published by the Free Software Foundation.
10  *
11  * This program is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14  * GNU General Public License for more details.
15  *
16  * You should have received a copy of the GNU General Public License
17  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
18  */
19 #ifndef __ASM_PAGE_H
20 #define __ASM_PAGE_H
21 
22 /* PAGE_SHIFT determines the page size */
23 #ifdef CONFIG_ARM64_64K_PAGES
24 #define PAGE_SHIFT		16
25 #else
26 #define PAGE_SHIFT		12
27 #endif
28 #define PAGE_SIZE		(_AC(1,UL) << PAGE_SHIFT)
29 #define PAGE_MASK		(~(PAGE_SIZE-1))
30 
31 /*
32  * The idmap and swapper page tables need some space reserved in the kernel
33  * image. Both require pgd, pud (4 levels only) and pmd tables to (section)
34  * map the kernel. With the 64K page configuration, swapper and idmap need to
35  * map to pte level. The swapper also maps the FDT (see __create_page_tables
36  * for more information). Note that the number of ID map translation levels
37  * could be increased on the fly if system RAM is out of reach for the default
38  * VA range, so 3 pages are reserved in all cases.
39  */
40 #ifdef CONFIG_ARM64_64K_PAGES
41 #define SWAPPER_PGTABLE_LEVELS	(CONFIG_PGTABLE_LEVELS)
42 #else
43 #define SWAPPER_PGTABLE_LEVELS	(CONFIG_PGTABLE_LEVELS - 1)
44 #endif
45 
46 #define SWAPPER_DIR_SIZE	(SWAPPER_PGTABLE_LEVELS * PAGE_SIZE)
47 #define IDMAP_DIR_SIZE		(3 * PAGE_SIZE)
48 
49 #ifndef __ASSEMBLY__
50 
51 #include <asm/pgtable-types.h>
52 
53 extern void __cpu_clear_user_page(void *p, unsigned long user);
54 extern void __cpu_copy_user_page(void *to, const void *from,
55 				 unsigned long user);
56 extern void copy_page(void *to, const void *from);
57 extern void clear_page(void *to);
58 
59 #define clear_user_page(addr,vaddr,pg)  __cpu_clear_user_page(addr, vaddr)
60 #define copy_user_page(to,from,vaddr,pg) __cpu_copy_user_page(to, from, vaddr)
61 
62 typedef struct page *pgtable_t;
63 
64 #ifdef CONFIG_HAVE_ARCH_PFN_VALID
65 extern int pfn_valid(unsigned long);
66 #endif
67 
68 #include <asm/memory.h>
69 
70 #endif /* !__ASSEMBLY__ */
71 
72 #define VM_DATA_DEFAULT_FLAGS \
73 	(((current->personality & READ_IMPLIES_EXEC) ? VM_EXEC : 0) | \
74 	 VM_READ | VM_WRITE | VM_MAYREAD | VM_MAYWRITE | VM_MAYEXEC)
75 
76 #include <asm-generic/getorder.h>
77 
78 #endif
79