xref: /openbmc/linux/arch/arm64/include/asm/memory.h (revision 4fc4dca8)
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 <linux/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  * VMEMMAP_SIZE - allows the whole linear region to be covered by
39  *                a struct page array
40  */
41 #define VMEMMAP_SIZE (UL(1) << (VA_BITS - PAGE_SHIFT - 1 + STRUCT_PAGE_MAX_SHIFT))
42 
43 /*
44  * PAGE_OFFSET - the virtual address of the start of the linear map (top
45  *		 (VA_BITS - 1))
46  * KIMAGE_VADDR - the virtual address of the start of the kernel image
47  * VA_BITS - the maximum number of bits for virtual addresses.
48  * VA_START - the first kernel virtual address.
49  */
50 #define VA_BITS			(CONFIG_ARM64_VA_BITS)
51 #define VA_START		(UL(0xffffffffffffffff) - \
52 	(UL(1) << VA_BITS) + 1)
53 #define PAGE_OFFSET		(UL(0xffffffffffffffff) - \
54 	(UL(1) << (VA_BITS - 1)) + 1)
55 #define KIMAGE_VADDR		(MODULES_END)
56 #define BPF_JIT_REGION_START	(VA_START + KASAN_SHADOW_SIZE)
57 #define BPF_JIT_REGION_SIZE	(SZ_128M)
58 #define BPF_JIT_REGION_END	(BPF_JIT_REGION_START + BPF_JIT_REGION_SIZE)
59 #define MODULES_END		(MODULES_VADDR + MODULES_VSIZE)
60 #define MODULES_VADDR		(BPF_JIT_REGION_END)
61 #define MODULES_VSIZE		(SZ_128M)
62 #define VMEMMAP_START		(PAGE_OFFSET - VMEMMAP_SIZE)
63 #define PCI_IO_END		(VMEMMAP_START - SZ_2M)
64 #define PCI_IO_START		(PCI_IO_END - PCI_IO_SIZE)
65 #define FIXADDR_TOP		(PCI_IO_START - SZ_2M)
66 
67 #define KERNEL_START      _text
68 #define KERNEL_END        _end
69 
70 #ifdef CONFIG_ARM64_USER_VA_BITS_52
71 #define MAX_USER_VA_BITS	52
72 #else
73 #define MAX_USER_VA_BITS	VA_BITS
74 #endif
75 
76 /*
77  * Generic and tag-based KASAN require 1/8th and 1/16th of the kernel virtual
78  * address space for the shadow region respectively. They can bloat the stack
79  * significantly, so double the (minimum) stack size when they are in use.
80  */
81 #ifdef CONFIG_KASAN
82 #define KASAN_SHADOW_SIZE	(UL(1) << (VA_BITS - KASAN_SHADOW_SCALE_SHIFT))
83 #define KASAN_THREAD_SHIFT	1
84 #else
85 #define KASAN_SHADOW_SIZE	(0)
86 #define KASAN_THREAD_SHIFT	0
87 #endif
88 
89 #define MIN_THREAD_SHIFT	(14 + KASAN_THREAD_SHIFT)
90 
91 /*
92  * VMAP'd stacks are allocated at page granularity, so we must ensure that such
93  * stacks are a multiple of page size.
94  */
95 #if defined(CONFIG_VMAP_STACK) && (MIN_THREAD_SHIFT < PAGE_SHIFT)
96 #define THREAD_SHIFT		PAGE_SHIFT
97 #else
98 #define THREAD_SHIFT		MIN_THREAD_SHIFT
99 #endif
100 
101 #if THREAD_SHIFT >= PAGE_SHIFT
102 #define THREAD_SIZE_ORDER	(THREAD_SHIFT - PAGE_SHIFT)
103 #endif
104 
105 #define THREAD_SIZE		(UL(1) << THREAD_SHIFT)
106 
107 /*
108  * By aligning VMAP'd stacks to 2 * THREAD_SIZE, we can detect overflow by
109  * checking sp & (1 << THREAD_SHIFT), which we can do cheaply in the entry
110  * assembly.
111  */
112 #ifdef CONFIG_VMAP_STACK
113 #define THREAD_ALIGN		(2 * THREAD_SIZE)
114 #else
115 #define THREAD_ALIGN		THREAD_SIZE
116 #endif
117 
118 #define IRQ_STACK_SIZE		THREAD_SIZE
119 
120 #define OVERFLOW_STACK_SIZE	SZ_4K
121 
122 /*
123  * Alignment of kernel segments (e.g. .text, .data).
124  */
125 #if defined(CONFIG_DEBUG_ALIGN_RODATA)
126 /*
127  *  4 KB granule:   1 level 2 entry
128  * 16 KB granule: 128 level 3 entries, with contiguous bit
129  * 64 KB granule:  32 level 3 entries, with contiguous bit
130  */
131 #define SEGMENT_ALIGN			SZ_2M
132 #else
133 /*
134  *  4 KB granule:  16 level 3 entries, with contiguous bit
135  * 16 KB granule:   4 level 3 entries, without contiguous bit
136  * 64 KB granule:   1 level 3 entry
137  */
138 #define SEGMENT_ALIGN			SZ_64K
139 #endif
140 
141 /*
142  * Memory types available.
143  */
144 #define MT_DEVICE_nGnRnE	0
145 #define MT_DEVICE_nGnRE		1
146 #define MT_DEVICE_GRE		2
147 #define MT_NORMAL_NC		3
148 #define MT_NORMAL		4
149 #define MT_NORMAL_WT		5
150 
151 /*
152  * Memory types for Stage-2 translation
153  */
154 #define MT_S2_NORMAL		0xf
155 #define MT_S2_DEVICE_nGnRE	0x1
156 
157 /*
158  * Memory types for Stage-2 translation when ID_AA64MMFR2_EL1.FWB is 0001
159  * Stage-2 enforces Normal-WB and Device-nGnRE
160  */
161 #define MT_S2_FWB_NORMAL	6
162 #define MT_S2_FWB_DEVICE_nGnRE	1
163 
164 #ifdef CONFIG_ARM64_4K_PAGES
165 #define IOREMAP_MAX_ORDER	(PUD_SHIFT)
166 #else
167 #define IOREMAP_MAX_ORDER	(PMD_SHIFT)
168 #endif
169 
170 #ifndef __ASSEMBLY__
171 
172 #include <linux/bitops.h>
173 #include <linux/mmdebug.h>
174 
175 extern s64			memstart_addr;
176 /* PHYS_OFFSET - the physical address of the start of memory. */
177 #define PHYS_OFFSET		({ VM_BUG_ON(memstart_addr & 1); memstart_addr; })
178 
179 /* the virtual base of the kernel image (minus TEXT_OFFSET) */
180 extern u64			kimage_vaddr;
181 
182 /* the offset between the kernel virtual and physical mappings */
183 extern u64			kimage_voffset;
184 
185 static inline unsigned long kaslr_offset(void)
186 {
187 	return kimage_vaddr - KIMAGE_VADDR;
188 }
189 
190 /* the actual size of a user virtual address */
191 extern u64			vabits_user;
192 
193 /*
194  * Allow all memory at the discovery stage. We will clip it later.
195  */
196 #define MIN_MEMBLOCK_ADDR	0
197 #define MAX_MEMBLOCK_ADDR	U64_MAX
198 
199 /*
200  * PFNs are used to describe any physical page; this means
201  * PFN 0 == physical address 0.
202  *
203  * This is the PFN of the first RAM page in the kernel
204  * direct-mapped view.  We assume this is the first page
205  * of RAM in the mem_map as well.
206  */
207 #define PHYS_PFN_OFFSET	(PHYS_OFFSET >> PAGE_SHIFT)
208 
209 /*
210  * When dealing with data aborts, watchpoints, or instruction traps we may end
211  * up with a tagged userland pointer. Clear the tag to get a sane pointer to
212  * pass on to access_ok(), for instance.
213  */
214 #define untagged_addr(addr)	\
215 	((__typeof__(addr))sign_extend64((u64)(addr), 55))
216 
217 #ifdef CONFIG_KASAN_SW_TAGS
218 #define __tag_shifted(tag)	((u64)(tag) << 56)
219 #define __tag_set(addr, tag)	(__typeof__(addr))( \
220 		((u64)(addr) & ~__tag_shifted(0xff)) | __tag_shifted(tag))
221 #define __tag_reset(addr)	untagged_addr(addr)
222 #define __tag_get(addr)		(__u8)((u64)(addr) >> 56)
223 #else
224 #define __tag_set(addr, tag)	(addr)
225 #define __tag_reset(addr)	(addr)
226 #define __tag_get(addr)		0
227 #endif
228 
229 /*
230  * Physical vs virtual RAM address space conversion.  These are
231  * private definitions which should NOT be used outside memory.h
232  * files.  Use virt_to_phys/phys_to_virt/__pa/__va instead.
233  */
234 
235 
236 /*
237  * The linear kernel range starts in the middle of the virtual adddress
238  * space. Testing the top bit for the start of the region is a
239  * sufficient check.
240  */
241 #define __is_lm_address(addr)	(!!((addr) & BIT(VA_BITS - 1)))
242 
243 #define __lm_to_phys(addr)	(((addr) & ~PAGE_OFFSET) + PHYS_OFFSET)
244 #define __kimg_to_phys(addr)	((addr) - kimage_voffset)
245 
246 #define __virt_to_phys_nodebug(x) ({					\
247 	phys_addr_t __x = (phys_addr_t)(x);				\
248 	__is_lm_address(__x) ? __lm_to_phys(__x) :			\
249 			       __kimg_to_phys(__x);			\
250 })
251 
252 #define __pa_symbol_nodebug(x)	__kimg_to_phys((phys_addr_t)(x))
253 
254 #ifdef CONFIG_DEBUG_VIRTUAL
255 extern phys_addr_t __virt_to_phys(unsigned long x);
256 extern phys_addr_t __phys_addr_symbol(unsigned long x);
257 #else
258 #define __virt_to_phys(x)	__virt_to_phys_nodebug(x)
259 #define __phys_addr_symbol(x)	__pa_symbol_nodebug(x)
260 #endif
261 
262 #define __phys_to_virt(x)	((unsigned long)((x) - PHYS_OFFSET) | PAGE_OFFSET)
263 #define __phys_to_kimg(x)	((unsigned long)((x) + kimage_voffset))
264 
265 /*
266  * Convert a page to/from a physical address
267  */
268 #define page_to_phys(page)	(__pfn_to_phys(page_to_pfn(page)))
269 #define phys_to_page(phys)	(pfn_to_page(__phys_to_pfn(phys)))
270 
271 /*
272  * Note: Drivers should NOT use these.  They are the wrong
273  * translation for translating DMA addresses.  Use the driver
274  * DMA support - see dma-mapping.h.
275  */
276 #define virt_to_phys virt_to_phys
277 static inline phys_addr_t virt_to_phys(const volatile void *x)
278 {
279 	return __virt_to_phys((unsigned long)(x));
280 }
281 
282 #define phys_to_virt phys_to_virt
283 static inline void *phys_to_virt(phys_addr_t x)
284 {
285 	return (void *)(__phys_to_virt(x));
286 }
287 
288 /*
289  * Drivers should NOT use these either.
290  */
291 #define __pa(x)			__virt_to_phys((unsigned long)(x))
292 #define __pa_symbol(x)		__phys_addr_symbol(RELOC_HIDE((unsigned long)(x), 0))
293 #define __pa_nodebug(x)		__virt_to_phys_nodebug((unsigned long)(x))
294 #define __va(x)			((void *)__phys_to_virt((phys_addr_t)(x)))
295 #define pfn_to_kaddr(pfn)	__va((pfn) << PAGE_SHIFT)
296 #define virt_to_pfn(x)      __phys_to_pfn(__virt_to_phys((unsigned long)(x)))
297 #define sym_to_pfn(x)	    __phys_to_pfn(__pa_symbol(x))
298 
299 /*
300  *  virt_to_page(k)	convert a _valid_ virtual address to struct page *
301  *  virt_addr_valid(k)	indicates whether a virtual address is valid
302  */
303 #define ARCH_PFN_OFFSET		((unsigned long)PHYS_PFN_OFFSET)
304 
305 #if !defined(CONFIG_SPARSEMEM_VMEMMAP) || defined(CONFIG_DEBUG_VIRTUAL)
306 #define virt_to_page(kaddr)	pfn_to_page(__pa(kaddr) >> PAGE_SHIFT)
307 #define _virt_addr_valid(kaddr)	pfn_valid(__pa(kaddr) >> PAGE_SHIFT)
308 #else
309 #define __virt_to_pgoff(kaddr)	(((u64)(kaddr) & ~PAGE_OFFSET) / PAGE_SIZE * sizeof(struct page))
310 #define __page_to_voff(kaddr)	(((u64)(kaddr) & ~VMEMMAP_START) * PAGE_SIZE / sizeof(struct page))
311 
312 #define page_to_virt(page)	({					\
313 	unsigned long __addr =						\
314 		((__page_to_voff(page)) | PAGE_OFFSET);			\
315 	unsigned long __addr_tag =					\
316 		 __tag_set(__addr, page_kasan_tag(page));		\
317 	((void *)__addr_tag);						\
318 })
319 
320 #define virt_to_page(vaddr)	((struct page *)((__virt_to_pgoff(vaddr)) | VMEMMAP_START))
321 
322 #define _virt_addr_valid(kaddr)	pfn_valid((((u64)(kaddr) & ~PAGE_OFFSET) \
323 					   + PHYS_OFFSET) >> PAGE_SHIFT)
324 #endif
325 #endif
326 
327 #define _virt_addr_is_linear(kaddr)	\
328 	(__tag_reset((u64)(kaddr)) >= PAGE_OFFSET)
329 #define virt_addr_valid(kaddr)		\
330 	(_virt_addr_is_linear(kaddr) && _virt_addr_valid(kaddr))
331 
332 /*
333  * Given that the GIC architecture permits ITS implementations that can only be
334  * configured with a LPI table address once, GICv3 systems with many CPUs may
335  * end up reserving a lot of different regions after a kexec for their LPI
336  * tables (one per CPU), as we are forced to reuse the same memory after kexec
337  * (and thus reserve it persistently with EFI beforehand)
338  */
339 #if defined(CONFIG_EFI) && defined(CONFIG_ARM_GIC_V3_ITS)
340 # define INIT_MEMBLOCK_RESERVED_REGIONS	(INIT_MEMBLOCK_REGIONS + NR_CPUS + 1)
341 #endif
342 
343 #include <asm-generic/memory_model.h>
344 
345 #endif
346