1 /* SPDX-License-Identifier: GPL-2.0-only */
2 /*
3 * Based on arch/arm/include/asm/memory.h
4 *
5 * Copyright (C) 2000-2002 Russell King
6 * Copyright (C) 2012 ARM Ltd.
7 *
8 * Note: this file should not be included by non-asm/.h files
9 */
10 #ifndef __ASM_MEMORY_H
11 #define __ASM_MEMORY_H
12
13 #include <linux/const.h>
14 #include <linux/sizes.h>
15 #include <asm/page-def.h>
16
17 /*
18 * Size of the PCI I/O space. This must remain a power of two so that
19 * IO_SPACE_LIMIT acts as a mask for the low bits of I/O addresses.
20 */
21 #define PCI_IO_SIZE SZ_16M
22
23 /*
24 * VMEMMAP_SIZE - allows the whole linear region to be covered by
25 * a struct page array
26 *
27 * If we are configured with a 52-bit kernel VA then our VMEMMAP_SIZE
28 * needs to cover the memory region from the beginning of the 52-bit
29 * PAGE_OFFSET all the way to PAGE_END for 48-bit. This allows us to
30 * keep a constant PAGE_OFFSET and "fallback" to using the higher end
31 * of the VMEMMAP where 52-bit support is not available in hardware.
32 */
33 #define VMEMMAP_SIZE ((_PAGE_END(VA_BITS_MIN) - PAGE_OFFSET) \
34 >> (PAGE_SHIFT - STRUCT_PAGE_MAX_SHIFT))
35
36 /*
37 * PAGE_OFFSET - the virtual address of the start of the linear map, at the
38 * start of the TTBR1 address space.
39 * PAGE_END - the end of the linear map, where all other kernel mappings begin.
40 * KIMAGE_VADDR - the virtual address of the start of the kernel image.
41 * VA_BITS - the maximum number of bits for virtual addresses.
42 */
43 #define VA_BITS (CONFIG_ARM64_VA_BITS)
44 #define _PAGE_OFFSET(va) (-(UL(1) << (va)))
45 #define PAGE_OFFSET (_PAGE_OFFSET(VA_BITS))
46 #define KIMAGE_VADDR (MODULES_END)
47 #define BPF_JIT_REGION_START (KASAN_SHADOW_END)
48 #define BPF_JIT_REGION_SIZE (SZ_128M)
49 #define BPF_JIT_REGION_END (BPF_JIT_REGION_START + BPF_JIT_REGION_SIZE)
50 #define MODULES_END (MODULES_VADDR + MODULES_VSIZE)
51 #define MODULES_VADDR (BPF_JIT_REGION_END)
52 #define MODULES_VSIZE (SZ_128M)
53 #define VMEMMAP_START (-VMEMMAP_SIZE - SZ_2M)
54 #define VMEMMAP_END (VMEMMAP_START + VMEMMAP_SIZE)
55 #define PCI_IO_END (VMEMMAP_START - SZ_2M)
56 #define PCI_IO_START (PCI_IO_END - PCI_IO_SIZE)
57 #define FIXADDR_TOP (PCI_IO_START - SZ_2M)
58
59 #if VA_BITS > 48
60 #define VA_BITS_MIN (48)
61 #else
62 #define VA_BITS_MIN (VA_BITS)
63 #endif
64
65 #define _PAGE_END(va) (-(UL(1) << ((va) - 1)))
66
67 #define KERNEL_START _text
68 #define KERNEL_END _end
69
70 /*
71 * Generic and tag-based KASAN require 1/8th and 1/16th of the kernel virtual
72 * address space for the shadow region respectively. They can bloat the stack
73 * significantly, so double the (minimum) stack size when they are in use.
74 */
75 #ifdef CONFIG_KASAN
76 #define KASAN_SHADOW_OFFSET _AC(CONFIG_KASAN_SHADOW_OFFSET, UL)
77 #define KASAN_SHADOW_END ((UL(1) << (64 - KASAN_SHADOW_SCALE_SHIFT)) \
78 + KASAN_SHADOW_OFFSET)
79 #define KASAN_THREAD_SHIFT 1
80 #else
81 #define KASAN_THREAD_SHIFT 0
82 #define KASAN_SHADOW_END (_PAGE_END(VA_BITS_MIN))
83 #endif /* CONFIG_KASAN */
84
85 #define MIN_THREAD_SHIFT (14 + KASAN_THREAD_SHIFT)
86
87 /*
88 * VMAP'd stacks are allocated at page granularity, so we must ensure that such
89 * stacks are a multiple of page size.
90 */
91 #if defined(CONFIG_VMAP_STACK) && (MIN_THREAD_SHIFT < PAGE_SHIFT)
92 #define THREAD_SHIFT PAGE_SHIFT
93 #else
94 #define THREAD_SHIFT MIN_THREAD_SHIFT
95 #endif
96
97 #if THREAD_SHIFT >= PAGE_SHIFT
98 #define THREAD_SIZE_ORDER (THREAD_SHIFT - PAGE_SHIFT)
99 #endif
100
101 #define THREAD_SIZE (UL(1) << THREAD_SHIFT)
102
103 /*
104 * By aligning VMAP'd stacks to 2 * THREAD_SIZE, we can detect overflow by
105 * checking sp & (1 << THREAD_SHIFT), which we can do cheaply in the entry
106 * assembly.
107 */
108 #ifdef CONFIG_VMAP_STACK
109 #define THREAD_ALIGN (2 * THREAD_SIZE)
110 #else
111 #define THREAD_ALIGN THREAD_SIZE
112 #endif
113
114 #define IRQ_STACK_SIZE THREAD_SIZE
115
116 #define OVERFLOW_STACK_SIZE SZ_4K
117
118 /*
119 * Alignment of kernel segments (e.g. .text, .data).
120 *
121 * 4 KB granule: 16 level 3 entries, with contiguous bit
122 * 16 KB granule: 4 level 3 entries, without contiguous bit
123 * 64 KB granule: 1 level 3 entry
124 */
125 #define SEGMENT_ALIGN SZ_64K
126
127 /*
128 * Memory types available.
129 *
130 * IMPORTANT: MT_NORMAL must be index 0 since vm_get_page_prot() may 'or' in
131 * the MT_NORMAL_TAGGED memory type for PROT_MTE mappings. Note
132 * that protection_map[] only contains MT_NORMAL attributes.
133 */
134 #define MT_NORMAL 0
135 #define MT_NORMAL_TAGGED 1
136 #define MT_NORMAL_NC 2
137 #define MT_NORMAL_WT 3
138 #define MT_DEVICE_nGnRnE 4
139 #define MT_DEVICE_nGnRE 5
140 #define MT_DEVICE_GRE 6
141
142 /*
143 * Memory types for Stage-2 translation
144 */
145 #define MT_S2_NORMAL 0xf
146 #define MT_S2_DEVICE_nGnRE 0x1
147
148 /*
149 * Memory types for Stage-2 translation when ID_AA64MMFR2_EL1.FWB is 0001
150 * Stage-2 enforces Normal-WB and Device-nGnRE
151 */
152 #define MT_S2_FWB_NORMAL 6
153 #define MT_S2_FWB_DEVICE_nGnRE 1
154
155 #ifdef CONFIG_ARM64_4K_PAGES
156 #define IOREMAP_MAX_ORDER (PUD_SHIFT)
157 #else
158 #define IOREMAP_MAX_ORDER (PMD_SHIFT)
159 #endif
160
161 #ifndef __ASSEMBLY__
162
163 #include <linux/bitops.h>
164 #include <linux/compiler.h>
165 #include <linux/mmdebug.h>
166 #include <linux/types.h>
167 #include <asm/bug.h>
168
169 extern u64 vabits_actual;
170 #define PAGE_END (_PAGE_END(vabits_actual))
171
172 extern s64 memstart_addr;
173 /* PHYS_OFFSET - the physical address of the start of memory. */
174 #define PHYS_OFFSET ({ VM_BUG_ON(memstart_addr & 1); memstart_addr; })
175
176 /* the virtual base of the kernel image */
177 extern u64 kimage_vaddr;
178
179 /* the offset between the kernel virtual and physical mappings */
180 extern u64 kimage_voffset;
181
kaslr_offset(void)182 static inline unsigned long kaslr_offset(void)
183 {
184 return kimage_vaddr - KIMAGE_VADDR;
185 }
186
187 /*
188 * Allow all memory at the discovery stage. We will clip it later.
189 */
190 #define MIN_MEMBLOCK_ADDR 0
191 #define MAX_MEMBLOCK_ADDR U64_MAX
192
193 /*
194 * PFNs are used to describe any physical page; this means
195 * PFN 0 == physical address 0.
196 *
197 * This is the PFN of the first RAM page in the kernel
198 * direct-mapped view. We assume this is the first page
199 * of RAM in the mem_map as well.
200 */
201 #define PHYS_PFN_OFFSET (PHYS_OFFSET >> PAGE_SHIFT)
202
203 /*
204 * When dealing with data aborts, watchpoints, or instruction traps we may end
205 * up with a tagged userland pointer. Clear the tag to get a sane pointer to
206 * pass on to access_ok(), for instance.
207 */
208 #define __untagged_addr(addr) \
209 ((__force __typeof__(addr))sign_extend64((__force u64)(addr), 55))
210
211 #define untagged_addr(addr) ({ \
212 u64 __addr = (__force u64)(addr); \
213 __addr &= __untagged_addr(__addr); \
214 (__force __typeof__(addr))__addr; \
215 })
216
217 #ifdef CONFIG_KASAN_SW_TAGS
218 #define __tag_shifted(tag) ((u64)(tag) << 56)
219 #define __tag_reset(addr) __untagged_addr(addr)
220 #define __tag_get(addr) (__u8)((u64)(addr) >> 56)
221 #else
222 #define __tag_shifted(tag) 0UL
223 #define __tag_reset(addr) (addr)
224 #define __tag_get(addr) 0
225 #endif /* CONFIG_KASAN_SW_TAGS */
226
__tag_set(const void * addr,u8 tag)227 static inline const void *__tag_set(const void *addr, u8 tag)
228 {
229 u64 __addr = (u64)addr & ~__tag_shifted(0xff);
230 return (const void *)(__addr | __tag_shifted(tag));
231 }
232
233 /*
234 * Physical vs virtual RAM address space conversion. These are
235 * private definitions which should NOT be used outside memory.h
236 * files. Use virt_to_phys/phys_to_virt/__pa/__va instead.
237 */
238
239
240 /*
241 * The linear kernel range starts at the bottom of the virtual address
242 * space. Testing the top bit for the start of the region is a
243 * sufficient check and avoids having to worry about the tag.
244 */
245 #define __is_lm_address(addr) (!(((u64)addr) & BIT(vabits_actual - 1)))
246
247 #define __lm_to_phys(addr) (((addr) & ~PAGE_OFFSET) + PHYS_OFFSET)
248 #define __kimg_to_phys(addr) ((addr) - kimage_voffset)
249
250 #define __virt_to_phys_nodebug(x) ({ \
251 phys_addr_t __x = (phys_addr_t)(__tag_reset(x)); \
252 __is_lm_address(__x) ? __lm_to_phys(__x) : __kimg_to_phys(__x); \
253 })
254
255 #define __pa_symbol_nodebug(x) __kimg_to_phys((phys_addr_t)(x))
256
257 #ifdef CONFIG_DEBUG_VIRTUAL
258 extern phys_addr_t __virt_to_phys(unsigned long x);
259 extern phys_addr_t __phys_addr_symbol(unsigned long x);
260 #else
261 #define __virt_to_phys(x) __virt_to_phys_nodebug(x)
262 #define __phys_addr_symbol(x) __pa_symbol_nodebug(x)
263 #endif /* CONFIG_DEBUG_VIRTUAL */
264
265 #define __phys_to_virt(x) ((unsigned long)((x) - PHYS_OFFSET) | PAGE_OFFSET)
266 #define __phys_to_kimg(x) ((unsigned long)((x) + kimage_voffset))
267
268 /*
269 * Convert a page to/from a physical address
270 */
271 #define page_to_phys(page) (__pfn_to_phys(page_to_pfn(page)))
272 #define phys_to_page(phys) (pfn_to_page(__phys_to_pfn(phys)))
273
274 /*
275 * Note: Drivers should NOT use these. They are the wrong
276 * translation for translating DMA addresses. Use the driver
277 * DMA support - see dma-mapping.h.
278 */
279 #define virt_to_phys virt_to_phys
virt_to_phys(const volatile void * x)280 static inline phys_addr_t virt_to_phys(const volatile void *x)
281 {
282 return __virt_to_phys((unsigned long)(x));
283 }
284
285 #define phys_to_virt phys_to_virt
phys_to_virt(phys_addr_t x)286 static inline void *phys_to_virt(phys_addr_t x)
287 {
288 return (void *)(__phys_to_virt(x));
289 }
290
291 /*
292 * Drivers should NOT use these either.
293 */
294 #define __pa(x) __virt_to_phys((unsigned long)(x))
295 #define __pa_symbol(x) __phys_addr_symbol(RELOC_HIDE((unsigned long)(x), 0))
296 #define __pa_nodebug(x) __virt_to_phys_nodebug((unsigned long)(x))
297 #define __va(x) ((void *)__phys_to_virt((phys_addr_t)(x)))
298 #define pfn_to_kaddr(pfn) __va((pfn) << PAGE_SHIFT)
299 #define virt_to_pfn(x) __phys_to_pfn(__virt_to_phys((unsigned long)(x)))
300 #define sym_to_pfn(x) __phys_to_pfn(__pa_symbol(x))
301
302 /*
303 * virt_to_page(x) convert a _valid_ virtual address to struct page *
304 * virt_addr_valid(x) indicates whether a virtual address is valid
305 */
306 #define ARCH_PFN_OFFSET ((unsigned long)PHYS_PFN_OFFSET)
307
308 #if !defined(CONFIG_SPARSEMEM_VMEMMAP) || defined(CONFIG_DEBUG_VIRTUAL)
309 #define virt_to_page(x) pfn_to_page(virt_to_pfn(x))
310 #else
311 #define page_to_virt(x) ({ \
312 __typeof__(x) __page = x; \
313 u64 __idx = ((u64)__page - VMEMMAP_START) / sizeof(struct page);\
314 u64 __addr = PAGE_OFFSET + (__idx * PAGE_SIZE); \
315 (void *)__tag_set((const void *)__addr, page_kasan_tag(__page));\
316 })
317
318 #define virt_to_page(x) ({ \
319 u64 __idx = (__tag_reset((u64)x) - PAGE_OFFSET) / PAGE_SIZE; \
320 u64 __addr = VMEMMAP_START + (__idx * sizeof(struct page)); \
321 (struct page *)__addr; \
322 })
323 #endif /* !CONFIG_SPARSEMEM_VMEMMAP || CONFIG_DEBUG_VIRTUAL */
324
325 #define virt_addr_valid(addr) ({ \
326 __typeof__(addr) __addr = addr; \
327 __is_lm_address(__addr) && pfn_valid(virt_to_pfn(__addr)); \
328 })
329
330 void dump_mem_limit(void);
331 #endif /* !ASSEMBLY */
332
333 /*
334 * Given that the GIC architecture permits ITS implementations that can only be
335 * configured with a LPI table address once, GICv3 systems with many CPUs may
336 * end up reserving a lot of different regions after a kexec for their LPI
337 * tables (one per CPU), as we are forced to reuse the same memory after kexec
338 * (and thus reserve it persistently with EFI beforehand)
339 */
340 #if defined(CONFIG_EFI) && defined(CONFIG_ARM_GIC_V3_ITS)
341 # define INIT_MEMBLOCK_RESERVED_REGIONS (INIT_MEMBLOCK_REGIONS + NR_CPUS + 1)
342 #endif
343
344 #include <asm-generic/memory_model.h>
345
346 #endif /* __ASM_MEMORY_H */
347
