Linux kernel mirror (for testing)
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linux
1/*
2 * Based on arch/arm/include/asm/memory.h
3 *
4 * Copyright (C) 2000-2002 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 * Note: this file should not be included by non-asm/.h files
20 */
21#ifndef __ASM_MEMORY_H
22#define __ASM_MEMORY_H
23
24#include <linux/compiler.h>
25#include <linux/const.h>
26#include <linux/types.h>
27#include <asm/bug.h>
28#include <asm/page-def.h>
29#include <asm/sizes.h>
30
31/*
32 * Size of the PCI I/O space. This must remain a power of two so that
33 * IO_SPACE_LIMIT acts as a mask for the low bits of I/O addresses.
34 */
35#define PCI_IO_SIZE SZ_16M
36
37/*
38 * Log2 of the upper bound of the size of a struct page. Used for sizing
39 * the vmemmap region only, does not affect actual memory footprint.
40 * We don't use sizeof(struct page) directly since taking its size here
41 * requires its definition to be available at this point in the inclusion
42 * chain, and it may not be a power of 2 in the first place.
43 */
44#define STRUCT_PAGE_MAX_SHIFT 6
45
46/*
47 * VMEMMAP_SIZE - allows the whole linear region to be covered by
48 * a struct page array
49 */
50#define VMEMMAP_SIZE (UL(1) << (VA_BITS - PAGE_SHIFT - 1 + STRUCT_PAGE_MAX_SHIFT))
51
52/*
53 * PAGE_OFFSET - the virtual address of the start of the linear map (top
54 * (VA_BITS - 1))
55 * KIMAGE_VADDR - the virtual address of the start of the kernel image
56 * VA_BITS - the maximum number of bits for virtual addresses.
57 * VA_START - the first kernel virtual address.
58 */
59#define VA_BITS (CONFIG_ARM64_VA_BITS)
60#define VA_START (UL(0xffffffffffffffff) - \
61 (UL(1) << VA_BITS) + 1)
62#define PAGE_OFFSET (UL(0xffffffffffffffff) - \
63 (UL(1) << (VA_BITS - 1)) + 1)
64#define KIMAGE_VADDR (MODULES_END)
65#define MODULES_END (MODULES_VADDR + MODULES_VSIZE)
66#define MODULES_VADDR (VA_START + KASAN_SHADOW_SIZE)
67#define MODULES_VSIZE (SZ_128M)
68#define VMEMMAP_START (PAGE_OFFSET - VMEMMAP_SIZE)
69#define PCI_IO_END (VMEMMAP_START - SZ_2M)
70#define PCI_IO_START (PCI_IO_END - PCI_IO_SIZE)
71#define FIXADDR_TOP (PCI_IO_START - SZ_2M)
72
73#define KERNEL_START _text
74#define KERNEL_END _end
75
76/*
77 * KASAN requires 1/8th of the kernel virtual address space for the shadow
78 * region. KASAN can bloat the stack significantly, so double the (minimum)
79 * stack size when KASAN is in use.
80 */
81#ifdef CONFIG_KASAN
82#define KASAN_SHADOW_SCALE_SHIFT 3
83#define KASAN_SHADOW_SIZE (UL(1) << (VA_BITS - KASAN_SHADOW_SCALE_SHIFT))
84#define KASAN_THREAD_SHIFT 1
85#else
86#define KASAN_SHADOW_SIZE (0)
87#define KASAN_THREAD_SHIFT 0
88#endif
89
90#define MIN_THREAD_SHIFT (14 + KASAN_THREAD_SHIFT)
91
92/*
93 * VMAP'd stacks are allocated at page granularity, so we must ensure that such
94 * stacks are a multiple of page size.
95 */
96#if defined(CONFIG_VMAP_STACK) && (MIN_THREAD_SHIFT < PAGE_SHIFT)
97#define THREAD_SHIFT PAGE_SHIFT
98#else
99#define THREAD_SHIFT MIN_THREAD_SHIFT
100#endif
101
102#if THREAD_SHIFT >= PAGE_SHIFT
103#define THREAD_SIZE_ORDER (THREAD_SHIFT - PAGE_SHIFT)
104#endif
105
106#define THREAD_SIZE (UL(1) << THREAD_SHIFT)
107
108/*
109 * By aligning VMAP'd stacks to 2 * THREAD_SIZE, we can detect overflow by
110 * checking sp & (1 << THREAD_SHIFT), which we can do cheaply in the entry
111 * assembly.
112 */
113#ifdef CONFIG_VMAP_STACK
114#define THREAD_ALIGN (2 * THREAD_SIZE)
115#else
116#define THREAD_ALIGN THREAD_SIZE
117#endif
118
119#define IRQ_STACK_SIZE THREAD_SIZE
120
121#define OVERFLOW_STACK_SIZE SZ_4K
122
123/*
124 * Alignment of kernel segments (e.g. .text, .data).
125 */
126#if defined(CONFIG_DEBUG_ALIGN_RODATA)
127/*
128 * 4 KB granule: 1 level 2 entry
129 * 16 KB granule: 128 level 3 entries, with contiguous bit
130 * 64 KB granule: 32 level 3 entries, with contiguous bit
131 */
132#define SEGMENT_ALIGN SZ_2M
133#else
134/*
135 * 4 KB granule: 16 level 3 entries, with contiguous bit
136 * 16 KB granule: 4 level 3 entries, without contiguous bit
137 * 64 KB granule: 1 level 3 entry
138 */
139#define SEGMENT_ALIGN SZ_64K
140#endif
141
142/*
143 * Memory types available.
144 */
145#define MT_DEVICE_nGnRnE 0
146#define MT_DEVICE_nGnRE 1
147#define MT_DEVICE_GRE 2
148#define MT_NORMAL_NC 3
149#define MT_NORMAL 4
150#define MT_NORMAL_WT 5
151
152/*
153 * Memory types for Stage-2 translation
154 */
155#define MT_S2_NORMAL 0xf
156#define MT_S2_DEVICE_nGnRE 0x1
157
158#ifdef CONFIG_ARM64_4K_PAGES
159#define IOREMAP_MAX_ORDER (PUD_SHIFT)
160#else
161#define IOREMAP_MAX_ORDER (PMD_SHIFT)
162#endif
163
164#ifdef CONFIG_BLK_DEV_INITRD
165#define __early_init_dt_declare_initrd(__start, __end) \
166 do { \
167 initrd_start = (__start); \
168 initrd_end = (__end); \
169 } while (0)
170#endif
171
172#ifndef __ASSEMBLY__
173
174#include <linux/bitops.h>
175#include <linux/mmdebug.h>
176
177extern s64 memstart_addr;
178/* PHYS_OFFSET - the physical address of the start of memory. */
179#define PHYS_OFFSET ({ VM_BUG_ON(memstart_addr & 1); memstart_addr; })
180
181/* the virtual base of the kernel image (minus TEXT_OFFSET) */
182extern u64 kimage_vaddr;
183
184/* the offset between the kernel virtual and physical mappings */
185extern u64 kimage_voffset;
186
187static inline unsigned long kaslr_offset(void)
188{
189 return kimage_vaddr - KIMAGE_VADDR;
190}
191
192/*
193 * Allow all memory at the discovery stage. We will clip it later.
194 */
195#define MIN_MEMBLOCK_ADDR 0
196#define MAX_MEMBLOCK_ADDR U64_MAX
197
198/*
199 * PFNs are used to describe any physical page; this means
200 * PFN 0 == physical address 0.
201 *
202 * This is the PFN of the first RAM page in the kernel
203 * direct-mapped view. We assume this is the first page
204 * of RAM in the mem_map as well.
205 */
206#define PHYS_PFN_OFFSET (PHYS_OFFSET >> PAGE_SHIFT)
207
208/*
209 * Physical vs virtual RAM address space conversion. These are
210 * private definitions which should NOT be used outside memory.h
211 * files. Use virt_to_phys/phys_to_virt/__pa/__va instead.
212 */
213
214
215/*
216 * The linear kernel range starts in the middle of the virtual adddress
217 * space. Testing the top bit for the start of the region is a
218 * sufficient check.
219 */
220#define __is_lm_address(addr) (!!((addr) & BIT(VA_BITS - 1)))
221
222#define __lm_to_phys(addr) (((addr) & ~PAGE_OFFSET) + PHYS_OFFSET)
223#define __kimg_to_phys(addr) ((addr) - kimage_voffset)
224
225#define __virt_to_phys_nodebug(x) ({ \
226 phys_addr_t __x = (phys_addr_t)(x); \
227 __is_lm_address(__x) ? __lm_to_phys(__x) : \
228 __kimg_to_phys(__x); \
229})
230
231#define __pa_symbol_nodebug(x) __kimg_to_phys((phys_addr_t)(x))
232
233#ifdef CONFIG_DEBUG_VIRTUAL
234extern phys_addr_t __virt_to_phys(unsigned long x);
235extern phys_addr_t __phys_addr_symbol(unsigned long x);
236#else
237#define __virt_to_phys(x) __virt_to_phys_nodebug(x)
238#define __phys_addr_symbol(x) __pa_symbol_nodebug(x)
239#endif
240
241#define __phys_to_virt(x) ((unsigned long)((x) - PHYS_OFFSET) | PAGE_OFFSET)
242#define __phys_to_kimg(x) ((unsigned long)((x) + kimage_voffset))
243
244/*
245 * Convert a page to/from a physical address
246 */
247#define page_to_phys(page) (__pfn_to_phys(page_to_pfn(page)))
248#define phys_to_page(phys) (pfn_to_page(__phys_to_pfn(phys)))
249
250/*
251 * Note: Drivers should NOT use these. They are the wrong
252 * translation for translating DMA addresses. Use the driver
253 * DMA support - see dma-mapping.h.
254 */
255#define virt_to_phys virt_to_phys
256static inline phys_addr_t virt_to_phys(const volatile void *x)
257{
258 return __virt_to_phys((unsigned long)(x));
259}
260
261#define phys_to_virt phys_to_virt
262static inline void *phys_to_virt(phys_addr_t x)
263{
264 return (void *)(__phys_to_virt(x));
265}
266
267/*
268 * Drivers should NOT use these either.
269 */
270#define __pa(x) __virt_to_phys((unsigned long)(x))
271#define __pa_symbol(x) __phys_addr_symbol(RELOC_HIDE((unsigned long)(x), 0))
272#define __pa_nodebug(x) __virt_to_phys_nodebug((unsigned long)(x))
273#define __va(x) ((void *)__phys_to_virt((phys_addr_t)(x)))
274#define pfn_to_kaddr(pfn) __va((pfn) << PAGE_SHIFT)
275#define virt_to_pfn(x) __phys_to_pfn(__virt_to_phys((unsigned long)(x)))
276#define sym_to_pfn(x) __phys_to_pfn(__pa_symbol(x))
277
278/*
279 * virt_to_page(k) convert a _valid_ virtual address to struct page *
280 * virt_addr_valid(k) indicates whether a virtual address is valid
281 */
282#define ARCH_PFN_OFFSET ((unsigned long)PHYS_PFN_OFFSET)
283
284#ifndef CONFIG_SPARSEMEM_VMEMMAP
285#define virt_to_page(kaddr) pfn_to_page(__pa(kaddr) >> PAGE_SHIFT)
286#define _virt_addr_valid(kaddr) pfn_valid(__pa(kaddr) >> PAGE_SHIFT)
287#else
288#define __virt_to_pgoff(kaddr) (((u64)(kaddr) & ~PAGE_OFFSET) / PAGE_SIZE * sizeof(struct page))
289#define __page_to_voff(kaddr) (((u64)(kaddr) & ~VMEMMAP_START) * PAGE_SIZE / sizeof(struct page))
290
291#define page_to_virt(page) ((void *)((__page_to_voff(page)) | PAGE_OFFSET))
292#define virt_to_page(vaddr) ((struct page *)((__virt_to_pgoff(vaddr)) | VMEMMAP_START))
293
294#define _virt_addr_valid(kaddr) pfn_valid((((u64)(kaddr) & ~PAGE_OFFSET) \
295 + PHYS_OFFSET) >> PAGE_SHIFT)
296#endif
297#endif
298
299#define _virt_addr_is_linear(kaddr) (((u64)(kaddr)) >= PAGE_OFFSET)
300#define virt_addr_valid(kaddr) (_virt_addr_is_linear(kaddr) && \
301 _virt_addr_valid(kaddr))
302
303#include <asm-generic/memory_model.h>
304
305#endif