xref: /openbmc/linux/arch/arm64/include/asm/memory.h (revision a20eefae)
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/types.h>
16 #include <asm/bug.h>
17 #include <asm/page-def.h>
18 #include <linux/sizes.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 #define VMEMMAP_SIZE (UL(1) << (VA_BITS - PAGE_SHIFT - 1 + STRUCT_PAGE_MAX_SHIFT))
31 
32 /*
33  * PAGE_OFFSET - the virtual address of the start of the linear map (top
34  *		 (VA_BITS - 1))
35  * KIMAGE_VADDR - the virtual address of the start of the kernel image
36  * VA_BITS - the maximum number of bits for virtual addresses.
37  * VA_START - the first kernel virtual address.
38  */
39 #define VA_BITS			(CONFIG_ARM64_VA_BITS)
40 #define VA_START		(UL(0xffffffffffffffff) - \
41 	(UL(1) << VA_BITS) + 1)
42 #define PAGE_OFFSET		(UL(0xffffffffffffffff) - \
43 	(UL(1) << (VA_BITS - 1)) + 1)
44 #define KIMAGE_VADDR		(MODULES_END)
45 #define BPF_JIT_REGION_START	(VA_START + KASAN_SHADOW_SIZE)
46 #define BPF_JIT_REGION_SIZE	(SZ_128M)
47 #define BPF_JIT_REGION_END	(BPF_JIT_REGION_START + BPF_JIT_REGION_SIZE)
48 #define MODULES_END		(MODULES_VADDR + MODULES_VSIZE)
49 #define MODULES_VADDR		(BPF_JIT_REGION_END)
50 #define MODULES_VSIZE		(SZ_128M)
51 #define VMEMMAP_START		(PAGE_OFFSET - 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 #define KERNEL_START      _text
57 #define KERNEL_END        _end
58 
59 #ifdef CONFIG_ARM64_USER_VA_BITS_52
60 #define MAX_USER_VA_BITS	52
61 #else
62 #define MAX_USER_VA_BITS	VA_BITS
63 #endif
64 
65 /*
66  * Generic and tag-based KASAN require 1/8th and 1/16th of the kernel virtual
67  * address space for the shadow region respectively. They can bloat the stack
68  * significantly, so double the (minimum) stack size when they are in use.
69  */
70 #ifdef CONFIG_KASAN
71 #define KASAN_SHADOW_SIZE	(UL(1) << (VA_BITS - KASAN_SHADOW_SCALE_SHIFT))
72 #define KASAN_THREAD_SHIFT	1
73 #else
74 #define KASAN_SHADOW_SIZE	(0)
75 #define KASAN_THREAD_SHIFT	0
76 #endif
77 
78 #define MIN_THREAD_SHIFT	(14 + KASAN_THREAD_SHIFT)
79 
80 /*
81  * VMAP'd stacks are allocated at page granularity, so we must ensure that such
82  * stacks are a multiple of page size.
83  */
84 #if defined(CONFIG_VMAP_STACK) && (MIN_THREAD_SHIFT < PAGE_SHIFT)
85 #define THREAD_SHIFT		PAGE_SHIFT
86 #else
87 #define THREAD_SHIFT		MIN_THREAD_SHIFT
88 #endif
89 
90 #if THREAD_SHIFT >= PAGE_SHIFT
91 #define THREAD_SIZE_ORDER	(THREAD_SHIFT - PAGE_SHIFT)
92 #endif
93 
94 #define THREAD_SIZE		(UL(1) << THREAD_SHIFT)
95 
96 /*
97  * By aligning VMAP'd stacks to 2 * THREAD_SIZE, we can detect overflow by
98  * checking sp & (1 << THREAD_SHIFT), which we can do cheaply in the entry
99  * assembly.
100  */
101 #ifdef CONFIG_VMAP_STACK
102 #define THREAD_ALIGN		(2 * THREAD_SIZE)
103 #else
104 #define THREAD_ALIGN		THREAD_SIZE
105 #endif
106 
107 #define IRQ_STACK_SIZE		THREAD_SIZE
108 
109 #define OVERFLOW_STACK_SIZE	SZ_4K
110 
111 /*
112  * Alignment of kernel segments (e.g. .text, .data).
113  */
114 #if defined(CONFIG_DEBUG_ALIGN_RODATA)
115 /*
116  *  4 KB granule:   1 level 2 entry
117  * 16 KB granule: 128 level 3 entries, with contiguous bit
118  * 64 KB granule:  32 level 3 entries, with contiguous bit
119  */
120 #define SEGMENT_ALIGN			SZ_2M
121 #else
122 /*
123  *  4 KB granule:  16 level 3 entries, with contiguous bit
124  * 16 KB granule:   4 level 3 entries, without contiguous bit
125  * 64 KB granule:   1 level 3 entry
126  */
127 #define SEGMENT_ALIGN			SZ_64K
128 #endif
129 
130 /*
131  * Memory types available.
132  */
133 #define MT_DEVICE_nGnRnE	0
134 #define MT_DEVICE_nGnRE		1
135 #define MT_DEVICE_GRE		2
136 #define MT_NORMAL_NC		3
137 #define MT_NORMAL		4
138 #define MT_NORMAL_WT		5
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/mmdebug.h>
163 
164 extern s64			memstart_addr;
165 /* PHYS_OFFSET - the physical address of the start of memory. */
166 #define PHYS_OFFSET		({ VM_BUG_ON(memstart_addr & 1); memstart_addr; })
167 
168 /* the virtual base of the kernel image (minus TEXT_OFFSET) */
169 extern u64			kimage_vaddr;
170 
171 /* the offset between the kernel virtual and physical mappings */
172 extern u64			kimage_voffset;
173 
174 static inline unsigned long kaslr_offset(void)
175 {
176 	return kimage_vaddr - KIMAGE_VADDR;
177 }
178 
179 /* the actual size of a user virtual address */
180 extern u64			vabits_user;
181 
182 /*
183  * Allow all memory at the discovery stage. We will clip it later.
184  */
185 #define MIN_MEMBLOCK_ADDR	0
186 #define MAX_MEMBLOCK_ADDR	U64_MAX
187 
188 /*
189  * PFNs are used to describe any physical page; this means
190  * PFN 0 == physical address 0.
191  *
192  * This is the PFN of the first RAM page in the kernel
193  * direct-mapped view.  We assume this is the first page
194  * of RAM in the mem_map as well.
195  */
196 #define PHYS_PFN_OFFSET	(PHYS_OFFSET >> PAGE_SHIFT)
197 
198 /*
199  * When dealing with data aborts, watchpoints, or instruction traps we may end
200  * up with a tagged userland pointer. Clear the tag to get a sane pointer to
201  * pass on to access_ok(), for instance.
202  */
203 #define untagged_addr(addr)	\
204 	((__typeof__(addr))sign_extend64((u64)(addr), 55))
205 
206 #ifdef CONFIG_KASAN_SW_TAGS
207 #define __tag_shifted(tag)	((u64)(tag) << 56)
208 #define __tag_set(addr, tag)	(__typeof__(addr))( \
209 		((u64)(addr) & ~__tag_shifted(0xff)) | __tag_shifted(tag))
210 #define __tag_reset(addr)	untagged_addr(addr)
211 #define __tag_get(addr)		(__u8)((u64)(addr) >> 56)
212 #else
213 #define __tag_set(addr, tag)	(addr)
214 #define __tag_reset(addr)	(addr)
215 #define __tag_get(addr)		0
216 #endif
217 
218 /*
219  * Physical vs virtual RAM address space conversion.  These are
220  * private definitions which should NOT be used outside memory.h
221  * files.  Use virt_to_phys/phys_to_virt/__pa/__va instead.
222  */
223 
224 
225 /*
226  * The linear kernel range starts in the middle of the virtual adddress
227  * space. Testing the top bit for the start of the region is a
228  * sufficient check.
229  */
230 #define __is_lm_address(addr)	(!!((addr) & BIT(VA_BITS - 1)))
231 
232 #define __lm_to_phys(addr)	(((addr) & ~PAGE_OFFSET) + PHYS_OFFSET)
233 #define __kimg_to_phys(addr)	((addr) - kimage_voffset)
234 
235 #define __virt_to_phys_nodebug(x) ({					\
236 	phys_addr_t __x = (phys_addr_t)(x);				\
237 	__is_lm_address(__x) ? __lm_to_phys(__x) :			\
238 			       __kimg_to_phys(__x);			\
239 })
240 
241 #define __pa_symbol_nodebug(x)	__kimg_to_phys((phys_addr_t)(x))
242 
243 #ifdef CONFIG_DEBUG_VIRTUAL
244 extern phys_addr_t __virt_to_phys(unsigned long x);
245 extern phys_addr_t __phys_addr_symbol(unsigned long x);
246 #else
247 #define __virt_to_phys(x)	__virt_to_phys_nodebug(x)
248 #define __phys_addr_symbol(x)	__pa_symbol_nodebug(x)
249 #endif
250 
251 #define __phys_to_virt(x)	((unsigned long)((x) - PHYS_OFFSET) | PAGE_OFFSET)
252 #define __phys_to_kimg(x)	((unsigned long)((x) + kimage_voffset))
253 
254 /*
255  * Convert a page to/from a physical address
256  */
257 #define page_to_phys(page)	(__pfn_to_phys(page_to_pfn(page)))
258 #define phys_to_page(phys)	(pfn_to_page(__phys_to_pfn(phys)))
259 
260 /*
261  * Note: Drivers should NOT use these.  They are the wrong
262  * translation for translating DMA addresses.  Use the driver
263  * DMA support - see dma-mapping.h.
264  */
265 #define virt_to_phys virt_to_phys
266 static inline phys_addr_t virt_to_phys(const volatile void *x)
267 {
268 	return __virt_to_phys((unsigned long)(x));
269 }
270 
271 #define phys_to_virt phys_to_virt
272 static inline void *phys_to_virt(phys_addr_t x)
273 {
274 	return (void *)(__phys_to_virt(x));
275 }
276 
277 /*
278  * Drivers should NOT use these either.
279  */
280 #define __pa(x)			__virt_to_phys((unsigned long)(x))
281 #define __pa_symbol(x)		__phys_addr_symbol(RELOC_HIDE((unsigned long)(x), 0))
282 #define __pa_nodebug(x)		__virt_to_phys_nodebug((unsigned long)(x))
283 #define __va(x)			((void *)__phys_to_virt((phys_addr_t)(x)))
284 #define pfn_to_kaddr(pfn)	__va((pfn) << PAGE_SHIFT)
285 #define virt_to_pfn(x)      __phys_to_pfn(__virt_to_phys((unsigned long)(x)))
286 #define sym_to_pfn(x)	    __phys_to_pfn(__pa_symbol(x))
287 
288 /*
289  *  virt_to_page(k)	convert a _valid_ virtual address to struct page *
290  *  virt_addr_valid(k)	indicates whether a virtual address is valid
291  */
292 #define ARCH_PFN_OFFSET		((unsigned long)PHYS_PFN_OFFSET)
293 
294 #if !defined(CONFIG_SPARSEMEM_VMEMMAP) || defined(CONFIG_DEBUG_VIRTUAL)
295 #define virt_to_page(kaddr)	pfn_to_page(__pa(kaddr) >> PAGE_SHIFT)
296 #define _virt_addr_valid(kaddr)	pfn_valid(__pa(kaddr) >> PAGE_SHIFT)
297 #else
298 #define __virt_to_pgoff(kaddr)	(((u64)(kaddr) & ~PAGE_OFFSET) / PAGE_SIZE * sizeof(struct page))
299 #define __page_to_voff(kaddr)	(((u64)(kaddr) & ~VMEMMAP_START) * PAGE_SIZE / sizeof(struct page))
300 
301 #define page_to_virt(page)	({					\
302 	unsigned long __addr =						\
303 		((__page_to_voff(page)) | PAGE_OFFSET);			\
304 	unsigned long __addr_tag =					\
305 		 __tag_set(__addr, page_kasan_tag(page));		\
306 	((void *)__addr_tag);						\
307 })
308 
309 #define virt_to_page(vaddr)	((struct page *)((__virt_to_pgoff(vaddr)) | VMEMMAP_START))
310 
311 #define _virt_addr_valid(kaddr)	pfn_valid((((u64)(kaddr) & ~PAGE_OFFSET) \
312 					   + PHYS_OFFSET) >> PAGE_SHIFT)
313 #endif
314 #endif
315 
316 #define _virt_addr_is_linear(kaddr)	\
317 	(__tag_reset((u64)(kaddr)) >= PAGE_OFFSET)
318 #define virt_addr_valid(kaddr)		\
319 	(_virt_addr_is_linear(kaddr) && _virt_addr_valid(kaddr))
320 
321 /*
322  * Given that the GIC architecture permits ITS implementations that can only be
323  * configured with a LPI table address once, GICv3 systems with many CPUs may
324  * end up reserving a lot of different regions after a kexec for their LPI
325  * tables (one per CPU), as we are forced to reuse the same memory after kexec
326  * (and thus reserve it persistently with EFI beforehand)
327  */
328 #if defined(CONFIG_EFI) && defined(CONFIG_ARM_GIC_V3_ITS)
329 # define INIT_MEMBLOCK_RESERVED_REGIONS	(INIT_MEMBLOCK_REGIONS + NR_CPUS + 1)
330 #endif
331 
332 #include <asm-generic/memory_model.h>
333 
334 #endif
335