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/compiler.h>
14 #include <linux/const.h>
15 #include <linux/sizes.h>
16 #include <linux/types.h>
17 #include <asm/bug.h>
18 #include <asm/page-def.h>
19
20 /*
21 * Size of the PCI I/O space. This must remain a power of two so that
22 * IO_SPACE_LIMIT acts as a mask for the low bits of I/O addresses.
23 */
24 #define PCI_IO_SIZE SZ_16M
25
26 /*
27 * VMEMMAP_SIZE - allows the whole linear region to be covered by
28 * a struct page array
29 *
30 * If we are configured with a 52-bit kernel VA then our VMEMMAP_SIZE
31 * needs to cover the memory region from the beginning of the 52-bit
32 * PAGE_OFFSET all the way to PAGE_END for 48-bit. This allows us to
33 * keep a constant PAGE_OFFSET and "fallback" to using the higher end
34 * of the VMEMMAP where 52-bit support is not available in hardware.
35 */
36 #define VMEMMAP_SIZE ((_PAGE_END(VA_BITS_MIN) - PAGE_OFFSET) \
37 >> (PAGE_SHIFT - STRUCT_PAGE_MAX_SHIFT))
38
39 /*
40 * PAGE_OFFSET - the virtual address of the start of the linear map, at the
41 * start of the TTBR1 address space.
42 * PAGE_END - the end of the linear map, where all other kernel mappings begin.
43 * KIMAGE_VADDR - the virtual address of the start of the kernel image.
44 * VA_BITS - the maximum number of bits for virtual addresses.
45 */
46 #define VA_BITS (CONFIG_ARM64_VA_BITS)
47 #define _PAGE_OFFSET(va) (-(UL(1) << (va)))
48 #define PAGE_OFFSET (_PAGE_OFFSET(VA_BITS))
49 #define KIMAGE_VADDR (MODULES_END)
50 #define BPF_JIT_REGION_START (KASAN_SHADOW_END)
51 #define BPF_JIT_REGION_SIZE (SZ_128M)
52 #define BPF_JIT_REGION_END (BPF_JIT_REGION_START + BPF_JIT_REGION_SIZE)
53 #define MODULES_END (MODULES_VADDR + MODULES_VSIZE)
54 #define MODULES_VADDR (BPF_JIT_REGION_END)
55 #define MODULES_VSIZE (SZ_128M)
56 #define VMEMMAP_START (-VMEMMAP_SIZE - SZ_2M)
57 #define PCI_IO_END (VMEMMAP_START - SZ_2M)
58 #define PCI_IO_START (PCI_IO_END - PCI_IO_SIZE)
59 #define FIXADDR_TOP (PCI_IO_START - SZ_2M)
60
61 #if VA_BITS > 48
62 #define VA_BITS_MIN (48)
63 #else
64 #define VA_BITS_MIN (VA_BITS)
65 #endif
66
67 #define _PAGE_END(va) (-(UL(1) << ((va) - 1)))
68
69 #define KERNEL_START _text
70 #define KERNEL_END _end
71
72 #ifdef CONFIG_ARM64_VA_BITS_52
73 #define MAX_USER_VA_BITS 52
74 #else
75 #define MAX_USER_VA_BITS VA_BITS
76 #endif
77
78 /*
79 * Generic and tag-based KASAN require 1/8th and 1/16th of the kernel virtual
80 * address space for the shadow region respectively. They can bloat the stack
81 * significantly, so double the (minimum) stack size when they are in use.
82 */
83 #ifdef CONFIG_KASAN
84 #define KASAN_SHADOW_OFFSET _AC(CONFIG_KASAN_SHADOW_OFFSET, UL)
85 #define KASAN_SHADOW_END ((UL(1) << (64 - KASAN_SHADOW_SCALE_SHIFT)) \
86 + KASAN_SHADOW_OFFSET)
87 #define KASAN_THREAD_SHIFT 1
88 #else
89 #define KASAN_THREAD_SHIFT 0
90 #define KASAN_SHADOW_END (_PAGE_END(VA_BITS_MIN))
91 #endif /* CONFIG_KASAN */
92
93 #define MIN_THREAD_SHIFT (14 + KASAN_THREAD_SHIFT)
94
95 /*
96 * VMAP'd stacks are allocated at page granularity, so we must ensure that such
97 * stacks are a multiple of page size.
98 */
99 #if defined(CONFIG_VMAP_STACK) && (MIN_THREAD_SHIFT < PAGE_SHIFT)
100 #define THREAD_SHIFT PAGE_SHIFT
101 #else
102 #define THREAD_SHIFT MIN_THREAD_SHIFT
103 #endif
104
105 #if THREAD_SHIFT >= PAGE_SHIFT
106 #define THREAD_SIZE_ORDER (THREAD_SHIFT - PAGE_SHIFT)
107 #endif
108
109 #define THREAD_SIZE (UL(1) << THREAD_SHIFT)
110
111 /*
112 * By aligning VMAP'd stacks to 2 * THREAD_SIZE, we can detect overflow by
113 * checking sp & (1 << THREAD_SHIFT), which we can do cheaply in the entry
114 * assembly.
115 */
116 #ifdef CONFIG_VMAP_STACK
117 #define THREAD_ALIGN (2 * THREAD_SIZE)
118 #else
119 #define THREAD_ALIGN THREAD_SIZE
120 #endif
121
122 #define IRQ_STACK_SIZE THREAD_SIZE
123
124 #define OVERFLOW_STACK_SIZE SZ_4K
125
126 /*
127 * Alignment of kernel segments (e.g. .text, .data).
128 */
129 #if defined(CONFIG_DEBUG_ALIGN_RODATA)
130 /*
131 * 4 KB granule: 1 level 2 entry
132 * 16 KB granule: 128 level 3 entries, with contiguous bit
133 * 64 KB granule: 32 level 3 entries, with contiguous bit
134 */
135 #define SEGMENT_ALIGN SZ_2M
136 #else
137 /*
138 * 4 KB granule: 16 level 3 entries, with contiguous bit
139 * 16 KB granule: 4 level 3 entries, without contiguous bit
140 * 64 KB granule: 1 level 3 entry
141 */
142 #define SEGMENT_ALIGN SZ_64K
143 #endif
144
145 /*
146 * Memory types available.
147 */
148 #define MT_DEVICE_nGnRnE 0
149 #define MT_DEVICE_nGnRE 1
150 #define MT_DEVICE_GRE 2
151 #define MT_NORMAL_NC 3
152 #define MT_NORMAL 4
153 #define MT_NORMAL_WT 5
154
155 /*
156 * Memory types for Stage-2 translation
157 */
158 #define MT_S2_NORMAL 0xf
159 #define MT_S2_DEVICE_nGnRE 0x1
160
161 /*
162 * Memory types for Stage-2 translation when ID_AA64MMFR2_EL1.FWB is 0001
163 * Stage-2 enforces Normal-WB and Device-nGnRE
164 */
165 #define MT_S2_FWB_NORMAL 6
166 #define MT_S2_FWB_DEVICE_nGnRE 1
167
168 #ifdef CONFIG_ARM64_4K_PAGES
169 #define IOREMAP_MAX_ORDER (PUD_SHIFT)
170 #else
171 #define IOREMAP_MAX_ORDER (PMD_SHIFT)
172 #endif
173
174 #ifndef __ASSEMBLY__
175 extern u64 vabits_actual;
176 #define PAGE_END (_PAGE_END(vabits_actual))
177
178 #include <linux/bitops.h>
179 #include <linux/mmdebug.h>
180
181 extern s64 physvirt_offset;
182 extern s64 memstart_addr;
183 /* PHYS_OFFSET - the physical address of the start of memory. */
184 #define PHYS_OFFSET ({ VM_BUG_ON(memstart_addr & 1); memstart_addr; })
185
186 /* the virtual base of the kernel image (minus TEXT_OFFSET) */
187 extern u64 kimage_vaddr;
188
189 /* the offset between the kernel virtual and physical mappings */
190 extern u64 kimage_voffset;
191
kaslr_offset(void)192 static inline unsigned long kaslr_offset(void)
193 {
194 return kimage_vaddr - KIMAGE_VADDR;
195 }
196
197 /*
198 * Allow all memory at the discovery stage. We will clip it later.
199 */
200 #define MIN_MEMBLOCK_ADDR 0
201 #define MAX_MEMBLOCK_ADDR U64_MAX
202
203 /*
204 * PFNs are used to describe any physical page; this means
205 * PFN 0 == physical address 0.
206 *
207 * This is the PFN of the first RAM page in the kernel
208 * direct-mapped view. We assume this is the first page
209 * of RAM in the mem_map as well.
210 */
211 #define PHYS_PFN_OFFSET (PHYS_OFFSET >> PAGE_SHIFT)
212
213 /*
214 * When dealing with data aborts, watchpoints, or instruction traps we may end
215 * up with a tagged userland pointer. Clear the tag to get a sane pointer to
216 * pass on to access_ok(), for instance.
217 */
218 #define __untagged_addr(addr) \
219 ((__force __typeof__(addr))sign_extend64((__force u64)(addr), 55))
220
221 #define untagged_addr(addr) ({ \
222 u64 __addr = (__force u64)(addr); \
223 __addr &= __untagged_addr(__addr); \
224 (__force __typeof__(addr))__addr; \
225 })
226
227 #ifdef CONFIG_KASAN_SW_TAGS
228 #define __tag_shifted(tag) ((u64)(tag) << 56)
229 #define __tag_reset(addr) __untagged_addr(addr)
230 #define __tag_get(addr) (__u8)((u64)(addr) >> 56)
231 #else
232 #define __tag_shifted(tag) 0UL
233 #define __tag_reset(addr) (addr)
234 #define __tag_get(addr) 0
235 #endif /* CONFIG_KASAN_SW_TAGS */
236
__tag_set(const void * addr,u8 tag)237 static inline const void *__tag_set(const void *addr, u8 tag)
238 {
239 u64 __addr = (u64)addr & ~__tag_shifted(0xff);
240 return (const void *)(__addr | __tag_shifted(tag));
241 }
242
243 /*
244 * Physical vs virtual RAM address space conversion. These are
245 * private definitions which should NOT be used outside memory.h
246 * files. Use virt_to_phys/phys_to_virt/__pa/__va instead.
247 */
248
249
250 /*
251 * Check whether an arbitrary address is within the linear map, which
252 * lives in the [PAGE_OFFSET, PAGE_END) interval at the bottom of the
253 * kernel's TTBR1 address range.
254 */
255 #define __is_lm_address(addr) (((u64)(addr) ^ PAGE_OFFSET) < (PAGE_END - PAGE_OFFSET))
256
257 #define __lm_to_phys(addr) (((addr) + physvirt_offset))
258 #define __kimg_to_phys(addr) ((addr) - kimage_voffset)
259
260 #define __virt_to_phys_nodebug(x) ({ \
261 phys_addr_t __x = (phys_addr_t)(__tag_reset(x)); \
262 __is_lm_address(__x) ? __lm_to_phys(__x) : __kimg_to_phys(__x); \
263 })
264
265 #define __pa_symbol_nodebug(x) __kimg_to_phys((phys_addr_t)(x))
266
267 #ifdef CONFIG_DEBUG_VIRTUAL
268 extern phys_addr_t __virt_to_phys(unsigned long x);
269 extern phys_addr_t __phys_addr_symbol(unsigned long x);
270 #else
271 #define __virt_to_phys(x) __virt_to_phys_nodebug(x)
272 #define __phys_addr_symbol(x) __pa_symbol_nodebug(x)
273 #endif /* CONFIG_DEBUG_VIRTUAL */
274
275 #define __phys_to_virt(x) ((unsigned long)((x) - physvirt_offset))
276 #define __phys_to_kimg(x) ((unsigned long)((x) + kimage_voffset))
277
278 /*
279 * Convert a page to/from a physical address
280 */
281 #define page_to_phys(page) (__pfn_to_phys(page_to_pfn(page)))
282 #define phys_to_page(phys) (pfn_to_page(__phys_to_pfn(phys)))
283
284 /*
285 * Note: Drivers should NOT use these. They are the wrong
286 * translation for translating DMA addresses. Use the driver
287 * DMA support - see dma-mapping.h.
288 */
289 #define virt_to_phys virt_to_phys
virt_to_phys(const volatile void * x)290 static inline phys_addr_t virt_to_phys(const volatile void *x)
291 {
292 return __virt_to_phys((unsigned long)(x));
293 }
294
295 #define phys_to_virt phys_to_virt
phys_to_virt(phys_addr_t x)296 static inline void *phys_to_virt(phys_addr_t x)
297 {
298 return (void *)(__phys_to_virt(x));
299 }
300
301 /*
302 * Drivers should NOT use these either.
303 */
304 #define __pa(x) __virt_to_phys((unsigned long)(x))
305 #define __pa_symbol(x) __phys_addr_symbol(RELOC_HIDE((unsigned long)(x), 0))
306 #define __pa_nodebug(x) __virt_to_phys_nodebug((unsigned long)(x))
307 #define __va(x) ((void *)__phys_to_virt((phys_addr_t)(x)))
308 #define pfn_to_kaddr(pfn) __va((pfn) << PAGE_SHIFT)
309 #define virt_to_pfn(x) __phys_to_pfn(__virt_to_phys((unsigned long)(x)))
310 #define sym_to_pfn(x) __phys_to_pfn(__pa_symbol(x))
311
312 /*
313 * With non-canonical CFI jump tables, the compiler replaces function
314 * address references with the address of the function's CFI jump
315 * table entry. This results in __pa_symbol(function) returning the
316 * physical address of the jump table entry, which can lead to address
317 * space confusion since the jump table points to the function's
318 * virtual address. Therefore, use inline assembly to ensure we are
319 * always taking the address of the actual function.
320 */
321 #define __va_function(x) ({ \
322 void *addr; \
323 asm("adrp %0, " __stringify(x) "\n\t" \
324 "add %0, %0, :lo12:" __stringify(x) : "=r" (addr)); \
325 addr; \
326 })
327
328 #define __pa_function(x) __pa_symbol(__va_function(x))
329
330 /*
331 * virt_to_page(x) convert a _valid_ virtual address to struct page *
332 * virt_addr_valid(x) indicates whether a virtual address is valid
333 */
334 #define ARCH_PFN_OFFSET ((unsigned long)PHYS_PFN_OFFSET)
335
336 #if !defined(CONFIG_SPARSEMEM_VMEMMAP) || defined(CONFIG_DEBUG_VIRTUAL)
337 #define page_to_virt(x) ({ \
338 __typeof__(x) __page = x; \
339 void *__addr = __va(page_to_phys(__page)); \
340 (void *)__tag_set((const void *)__addr, page_kasan_tag(__page));\
341 })
342 #define virt_to_page(x) pfn_to_page(virt_to_pfn(x))
343 #else
344 #define page_to_virt(x) ({ \
345 __typeof__(x) __page = x; \
346 u64 __idx = ((u64)__page - VMEMMAP_START) / sizeof(struct page);\
347 u64 __addr = PAGE_OFFSET + (__idx * PAGE_SIZE); \
348 (void *)__tag_set((const void *)__addr, page_kasan_tag(__page));\
349 })
350
351 #define virt_to_page(x) ({ \
352 u64 __idx = (__tag_reset((u64)x) - PAGE_OFFSET) / PAGE_SIZE; \
353 u64 __addr = VMEMMAP_START + (__idx * sizeof(struct page)); \
354 (struct page *)__addr; \
355 })
356 #endif /* !CONFIG_SPARSEMEM_VMEMMAP || CONFIG_DEBUG_VIRTUAL */
357
358 #define virt_addr_valid(addr) ({ \
359 __typeof__(addr) __addr = __tag_reset(addr); \
360 __is_lm_address(__addr) && pfn_valid(virt_to_pfn(__addr)); \
361 })
362
363 #endif /* !ASSEMBLY */
364
365 /*
366 * Given that the GIC architecture permits ITS implementations that can only be
367 * configured with a LPI table address once, GICv3 systems with many CPUs may
368 * end up reserving a lot of different regions after a kexec for their LPI
369 * tables (one per CPU), as we are forced to reuse the same memory after kexec
370 * (and thus reserve it persistently with EFI beforehand)
371 */
372 #if defined(CONFIG_EFI) && defined(CONFIG_ARM_GIC_V3_ITS)
373 # define INIT_MEMBLOCK_RESERVED_REGIONS (INIT_MEMBLOCK_REGIONS + NR_CPUS + 1)
374 #endif
375
376 #include <asm-generic/memory_model.h>
377
378 #endif /* __ASM_MEMORY_H */
379