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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 MODULES_END		(MODULES_VADDR + MODULES_VSIZE)
48 #define MODULES_VADDR		(KASAN_SHADOW_END)
49 #define MODULES_VSIZE		(SZ_128M)
50 #define VMEMMAP_START		(-VMEMMAP_SIZE - SZ_2M)
51 #define VMEMMAP_END		(VMEMMAP_START + VMEMMAP_SIZE)
52 #define PCI_IO_END		(VMEMMAP_START - SZ_2M)
53 #define PCI_IO_START		(PCI_IO_END - PCI_IO_SIZE)
54 #define FIXADDR_TOP		(PCI_IO_START - SZ_2M)
55 
56 #if VA_BITS > 48
57 #define VA_BITS_MIN		(48)
58 #else
59 #define VA_BITS_MIN		(VA_BITS)
60 #endif
61 
62 #define _PAGE_END(va)		(-(UL(1) << ((va) - 1)))
63 
64 #define KERNEL_START		_text
65 #define KERNEL_END		_end
66 
67 /*
68  * Generic and tag-based KASAN require 1/8th and 1/16th of the kernel virtual
69  * address space for the shadow region respectively. They can bloat the stack
70  * significantly, so double the (minimum) stack size when they are in use.
71  */
72 #if defined(CONFIG_KASAN_GENERIC) || defined(CONFIG_KASAN_SW_TAGS)
73 #define KASAN_SHADOW_OFFSET	_AC(CONFIG_KASAN_SHADOW_OFFSET, UL)
74 #define KASAN_SHADOW_END	((UL(1) << (64 - KASAN_SHADOW_SCALE_SHIFT)) \
75 					+ KASAN_SHADOW_OFFSET)
76 #define KASAN_THREAD_SHIFT	1
77 #else
78 #define KASAN_THREAD_SHIFT	0
79 #define KASAN_SHADOW_END	(_PAGE_END(VA_BITS_MIN))
80 #endif /* CONFIG_KASAN */
81 
82 #define MIN_THREAD_SHIFT	(14 + KASAN_THREAD_SHIFT)
83 
84 /*
85  * VMAP'd stacks are allocated at page granularity, so we must ensure that such
86  * stacks are a multiple of page size.
87  */
88 #if defined(CONFIG_VMAP_STACK) && (MIN_THREAD_SHIFT < PAGE_SHIFT)
89 #define THREAD_SHIFT		PAGE_SHIFT
90 #else
91 #define THREAD_SHIFT		MIN_THREAD_SHIFT
92 #endif
93 
94 #if THREAD_SHIFT >= PAGE_SHIFT
95 #define THREAD_SIZE_ORDER	(THREAD_SHIFT - PAGE_SHIFT)
96 #endif
97 
98 #define THREAD_SIZE		(UL(1) << THREAD_SHIFT)
99 
100 /*
101  * By aligning VMAP'd stacks to 2 * THREAD_SIZE, we can detect overflow by
102  * checking sp & (1 << THREAD_SHIFT), which we can do cheaply in the entry
103  * assembly.
104  */
105 #ifdef CONFIG_VMAP_STACK
106 #define THREAD_ALIGN		(2 * THREAD_SIZE)
107 #else
108 #define THREAD_ALIGN		THREAD_SIZE
109 #endif
110 
111 #define IRQ_STACK_SIZE		THREAD_SIZE
112 
113 #define OVERFLOW_STACK_SIZE	SZ_4K
114 
115 /*
116  * Alignment of kernel segments (e.g. .text, .data).
117  *
118  *  4 KB granule:  16 level 3 entries, with contiguous bit
119  * 16 KB granule:   4 level 3 entries, without contiguous bit
120  * 64 KB granule:   1 level 3 entry
121  */
122 #define SEGMENT_ALIGN		SZ_64K
123 
124 /*
125  * Memory types available.
126  *
127  * IMPORTANT: MT_NORMAL must be index 0 since vm_get_page_prot() may 'or' in
128  *	      the MT_NORMAL_TAGGED memory type for PROT_MTE mappings. Note
129  *	      that protection_map[] only contains MT_NORMAL attributes.
130  */
131 #define MT_NORMAL		0
132 #define MT_NORMAL_TAGGED	1
133 #define MT_NORMAL_NC		2
134 #define MT_NORMAL_WT		3
135 #define MT_DEVICE_nGnRnE	4
136 #define MT_DEVICE_nGnRE		5
137 #define MT_DEVICE_GRE		6
138 #define MT_NORMAL_iNC_oWB	7
139 
140 /*
141  * Memory types for Stage-2 translation
142  */
143 #define MT_S2_NORMAL		0xf
144 #define MT_S2_DEVICE_nGnRE	0x1
145 
146 /*
147  * Memory types for Stage-2 translation when ID_AA64MMFR2_EL1.FWB is 0001
148  * Stage-2 enforces Normal-WB and Device-nGnRE
149  */
150 #define MT_S2_FWB_NORMAL	6
151 #define MT_S2_FWB_DEVICE_nGnRE	1
152 
153 #ifdef CONFIG_ARM64_4K_PAGES
154 #define IOREMAP_MAX_ORDER	(PUD_SHIFT)
155 #else
156 #define IOREMAP_MAX_ORDER	(PMD_SHIFT)
157 #endif
158 
159 #ifndef __ASSEMBLY__
160 
161 #include <linux/bitops.h>
162 #include <linux/compiler.h>
163 #include <linux/mmdebug.h>
164 #include <linux/types.h>
165 #include <asm/bug.h>
166 
167 extern u64			vabits_actual;
168 #define PAGE_END		(_PAGE_END(vabits_actual))
169 
170 extern s64			memstart_addr;
171 /* PHYS_OFFSET - the physical address of the start of memory. */
172 #define PHYS_OFFSET		({ VM_BUG_ON(memstart_addr & 1); memstart_addr; })
173 
174 /* the virtual base of the kernel image */
175 extern u64			kimage_vaddr;
176 
177 /* the offset between the kernel virtual and physical mappings */
178 extern u64			kimage_voffset;
179 
kaslr_offset(void)180 static inline unsigned long kaslr_offset(void)
181 {
182 	return kimage_vaddr - KIMAGE_VADDR;
183 }
184 
185 /*
186  * Allow all memory at the discovery stage. We will clip it later.
187  */
188 #define MIN_MEMBLOCK_ADDR	0
189 #define MAX_MEMBLOCK_ADDR	U64_MAX
190 
191 /*
192  * PFNs are used to describe any physical page; this means
193  * PFN 0 == physical address 0.
194  *
195  * This is the PFN of the first RAM page in the kernel
196  * direct-mapped view.  We assume this is the first page
197  * of RAM in the mem_map as well.
198  */
199 #define PHYS_PFN_OFFSET	(PHYS_OFFSET >> PAGE_SHIFT)
200 
201 /*
202  * When dealing with data aborts, watchpoints, or instruction traps we may end
203  * up with a tagged userland pointer. Clear the tag to get a sane pointer to
204  * pass on to access_ok(), for instance.
205  */
206 #define __untagged_addr(addr)	\
207 	((__force __typeof__(addr))sign_extend64((__force u64)(addr), 55))
208 
209 #define untagged_addr(addr)	({					\
210 	u64 __addr = (__force u64)(addr);					\
211 	__addr &= __untagged_addr(__addr);				\
212 	(__force __typeof__(addr))__addr;				\
213 })
214 
215 #if defined(CONFIG_KASAN_SW_TAGS) || defined(CONFIG_KASAN_HW_TAGS)
216 #define __tag_shifted(tag)	((u64)(tag) << 56)
217 #define __tag_reset(addr)	__untagged_addr(addr)
218 #define __tag_get(addr)		(__u8)((u64)(addr) >> 56)
219 #else
220 #define __tag_shifted(tag)	0UL
221 #define __tag_reset(addr)	(addr)
222 #define __tag_get(addr)		0
223 #endif /* CONFIG_KASAN_SW_TAGS || CONFIG_KASAN_HW_TAGS */
224 
__tag_set(const void * addr,u8 tag)225 static inline const void *__tag_set(const void *addr, u8 tag)
226 {
227 	u64 __addr = (u64)addr & ~__tag_shifted(0xff);
228 	return (const void *)(__addr | __tag_shifted(tag));
229 }
230 
231 #ifdef CONFIG_KASAN_HW_TAGS
232 #define arch_enable_tagging_sync()		mte_enable_kernel_sync()
233 #define arch_enable_tagging_async()		mte_enable_kernel_async()
234 #define arch_set_tagging_report_once(state)	mte_set_report_once(state)
235 #define arch_force_async_tag_fault()		mte_check_tfsr_exit()
236 #define arch_get_random_tag()			mte_get_random_tag()
237 #define arch_get_mem_tag(addr)			mte_get_mem_tag(addr)
238 #define arch_set_mem_tag_range(addr, size, tag, init)	\
239 			mte_set_mem_tag_range((addr), (size), (tag), (init))
240 #endif /* CONFIG_KASAN_HW_TAGS */
241 
242 /*
243  * Physical vs virtual RAM address space conversion.  These are
244  * private definitions which should NOT be used outside memory.h
245  * files.  Use virt_to_phys/phys_to_virt/__pa/__va instead.
246  */
247 
248 
249 /*
250  * Check whether an arbitrary address is within the linear map, which
251  * lives in the [PAGE_OFFSET, PAGE_END) interval at the bottom of the
252  * kernel's TTBR1 address range.
253  */
254 #define __is_lm_address(addr)	(((u64)(addr) ^ PAGE_OFFSET) < (PAGE_END - PAGE_OFFSET))
255 
256 #define __lm_to_phys(addr)	(((addr) & ~PAGE_OFFSET) + PHYS_OFFSET)
257 #define __kimg_to_phys(addr)	((addr) - kimage_voffset)
258 
259 #define __virt_to_phys_nodebug(x) ({					\
260 	phys_addr_t __x = (phys_addr_t)(__tag_reset(x));		\
261 	__is_lm_address(__x) ? __lm_to_phys(__x) : __kimg_to_phys(__x);	\
262 })
263 
264 #define __pa_symbol_nodebug(x)	__kimg_to_phys((phys_addr_t)(x))
265 
266 #ifdef CONFIG_DEBUG_VIRTUAL
267 extern phys_addr_t __virt_to_phys(unsigned long x);
268 extern phys_addr_t __phys_addr_symbol(unsigned long x);
269 #else
270 #define __virt_to_phys(x)	__virt_to_phys_nodebug(x)
271 #define __phys_addr_symbol(x)	__pa_symbol_nodebug(x)
272 #endif /* CONFIG_DEBUG_VIRTUAL */
273 
274 #define __phys_to_virt(x)	((unsigned long)((x) - PHYS_OFFSET) | PAGE_OFFSET)
275 #define __phys_to_kimg(x)	((unsigned long)((x) + kimage_voffset))
276 
277 /*
278  * Convert a page to/from a physical address
279  */
280 #define page_to_phys(page)	(__pfn_to_phys(page_to_pfn(page)))
281 #define phys_to_page(phys)	(pfn_to_page(__phys_to_pfn(phys)))
282 
283 /*
284  * Note: Drivers should NOT use these.  They are the wrong
285  * translation for translating DMA addresses.  Use the driver
286  * DMA support - see dma-mapping.h.
287  */
288 #define virt_to_phys virt_to_phys
virt_to_phys(const volatile void * x)289 static inline phys_addr_t virt_to_phys(const volatile void *x)
290 {
291 	return __virt_to_phys((unsigned long)(x));
292 }
293 
294 #define phys_to_virt phys_to_virt
phys_to_virt(phys_addr_t x)295 static inline void *phys_to_virt(phys_addr_t x)
296 {
297 	return (void *)(__phys_to_virt(x));
298 }
299 
300 /*
301  * Drivers should NOT use these either.
302  */
303 #define __pa(x)			__virt_to_phys((unsigned long)(x))
304 #define __pa_symbol(x)		__phys_addr_symbol(RELOC_HIDE((unsigned long)(x), 0))
305 #define __pa_nodebug(x)		__virt_to_phys_nodebug((unsigned long)(x))
306 #define __va(x)			((void *)__phys_to_virt((phys_addr_t)(x)))
307 #define pfn_to_kaddr(pfn)	__va((pfn) << PAGE_SHIFT)
308 #define virt_to_pfn(x)		__phys_to_pfn(__virt_to_phys((unsigned long)(x)))
309 #define sym_to_pfn(x)		__phys_to_pfn(__pa_symbol(x))
310 
311 /*
312  * With non-canonical CFI jump tables, the compiler replaces function
313  * address references with the address of the function's CFI jump
314  * table entry. This results in __pa_symbol(function) returning the
315  * physical address of the jump table entry, which can lead to address
316  * space confusion since the jump table points to the function's
317  * virtual address. Therefore, use inline assembly to ensure we are
318  * always taking the address of the actual function.
319  */
320 #define __va_function(x) ({						\
321 	void *addr;							\
322 	asm("adrp %0, " __stringify(x) "\n\t"				\
323 	    "add  %0, %0, :lo12:" __stringify(x) : "=r" (addr));	\
324 	addr;								\
325 })
326 
327 #define __pa_function(x) 	__pa_symbol(__va_function(x))
328 
329 /*
330  *  virt_to_page(x)	convert a _valid_ virtual address to struct page *
331  *  virt_addr_valid(x)	indicates whether a virtual address is valid
332  */
333 #define ARCH_PFN_OFFSET		((unsigned long)PHYS_PFN_OFFSET)
334 
335 #if !defined(CONFIG_SPARSEMEM_VMEMMAP) || defined(CONFIG_DEBUG_VIRTUAL)
336 #define page_to_virt(x)	({						\
337 	__typeof__(x) __page = x;					\
338 	void *__addr = __va(page_to_phys(__page));			\
339 	(void *)__tag_set((const void *)__addr, page_kasan_tag(__page));\
340 })
341 #define virt_to_page(x)		pfn_to_page(virt_to_pfn(x))
342 #else
343 #define page_to_virt(x)	({						\
344 	__typeof__(x) __page = x;					\
345 	u64 __idx = ((u64)__page - VMEMMAP_START) / sizeof(struct page);\
346 	u64 __addr = PAGE_OFFSET + (__idx * PAGE_SIZE);			\
347 	(void *)__tag_set((const void *)__addr, page_kasan_tag(__page));\
348 })
349 
350 #define virt_to_page(x)	({						\
351 	u64 __idx = (__tag_reset((u64)x) - PAGE_OFFSET) / PAGE_SIZE;	\
352 	u64 __addr = VMEMMAP_START + (__idx * sizeof(struct page));	\
353 	(struct page *)__addr;						\
354 })
355 #endif /* !CONFIG_SPARSEMEM_VMEMMAP || CONFIG_DEBUG_VIRTUAL */
356 
357 #define virt_addr_valid(addr)	({					\
358 	__typeof__(addr) __addr = __tag_reset(addr);			\
359 	__is_lm_address(__addr) && pfn_valid(virt_to_pfn(__addr));	\
360 })
361 
362 void dump_mem_limit(void);
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