1 /* SPDX-License-Identifier: GPL-2.0-only */
3 * Based on arch/arm/include/asm/memory.h
5 * Copyright (C) 2000-2002 Russell King
6 * Copyright (C) 2012 ARM Ltd.
8 * Note: this file should not be included by non-asm/.h files
10 #ifndef __ASM_MEMORY_H
11 #define __ASM_MEMORY_H
13 #include <linux/compiler.h>
14 #include <linux/const.h>
15 #include <linux/types.h>
17 #include <asm/page-def.h>
18 #include <linux/sizes.h>
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.
24 #define PCI_IO_SIZE SZ_16M
27 * VMEMMAP_SIZE - allows the whole linear region to be covered by
30 * If we are configured with a 52-bit kernel VA then our VMEMMAP_SIZE
31 * neads to cover the memory region from the beginning of the 52-bit
32 * PAGE_OFFSET all the way to VA_START 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.
36 #define VMEMMAP_SIZE ((_VA_START(VA_BITS_MIN) - PAGE_OFFSET) \
37 >> (PAGE_SHIFT - STRUCT_PAGE_MAX_SHIFT))
40 * PAGE_OFFSET - the virtual address of the start of the linear map (top
42 * KIMAGE_VADDR - the virtual address of the start of the kernel image
43 * VA_BITS - the maximum number of bits for virtual addresses.
44 * VA_START - the first kernel virtual address.
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)
61 #define VA_BITS_MIN (48)
63 #define VA_BITS_MIN (VA_BITS)
65 #define _VA_START(va) (-(UL(1) << ((va) - 1)))
67 #define KERNEL_START _text
68 #define KERNEL_END _end
70 #ifdef CONFIG_ARM64_VA_BITS_52
71 #define MAX_USER_VA_BITS 52
73 #define MAX_USER_VA_BITS VA_BITS
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.
82 #define KASAN_SHADOW_OFFSET _AC(CONFIG_KASAN_SHADOW_OFFSET, UL)
83 #define KASAN_SHADOW_END ((UL(1) << (64 - KASAN_SHADOW_SCALE_SHIFT)) \
84 + KASAN_SHADOW_OFFSET)
85 #define KASAN_THREAD_SHIFT 1
87 #define KASAN_THREAD_SHIFT 0
88 #define KASAN_SHADOW_END (_VA_START(VA_BITS_MIN))
91 #define MIN_THREAD_SHIFT (14 + KASAN_THREAD_SHIFT)
94 * VMAP'd stacks are allocated at page granularity, so we must ensure that such
95 * stacks are a multiple of page size.
97 #if defined(CONFIG_VMAP_STACK) && (MIN_THREAD_SHIFT < PAGE_SHIFT)
98 #define THREAD_SHIFT PAGE_SHIFT
100 #define THREAD_SHIFT MIN_THREAD_SHIFT
103 #if THREAD_SHIFT >= PAGE_SHIFT
104 #define THREAD_SIZE_ORDER (THREAD_SHIFT - PAGE_SHIFT)
107 #define THREAD_SIZE (UL(1) << THREAD_SHIFT)
110 * By aligning VMAP'd stacks to 2 * THREAD_SIZE, we can detect overflow by
111 * checking sp & (1 << THREAD_SHIFT), which we can do cheaply in the entry
114 #ifdef CONFIG_VMAP_STACK
115 #define THREAD_ALIGN (2 * THREAD_SIZE)
117 #define THREAD_ALIGN THREAD_SIZE
120 #define IRQ_STACK_SIZE THREAD_SIZE
122 #define OVERFLOW_STACK_SIZE SZ_4K
125 * Alignment of kernel segments (e.g. .text, .data).
127 #if defined(CONFIG_DEBUG_ALIGN_RODATA)
129 * 4 KB granule: 1 level 2 entry
130 * 16 KB granule: 128 level 3 entries, with contiguous bit
131 * 64 KB granule: 32 level 3 entries, with contiguous bit
133 #define SEGMENT_ALIGN SZ_2M
136 * 4 KB granule: 16 level 3 entries, with contiguous bit
137 * 16 KB granule: 4 level 3 entries, without contiguous bit
138 * 64 KB granule: 1 level 3 entry
140 #define SEGMENT_ALIGN SZ_64K
144 * Memory types available.
146 #define MT_DEVICE_nGnRnE 0
147 #define MT_DEVICE_nGnRE 1
148 #define MT_DEVICE_GRE 2
149 #define MT_NORMAL_NC 3
151 #define MT_NORMAL_WT 5
154 * Memory types for Stage-2 translation
156 #define MT_S2_NORMAL 0xf
157 #define MT_S2_DEVICE_nGnRE 0x1
160 * Memory types for Stage-2 translation when ID_AA64MMFR2_EL1.FWB is 0001
161 * Stage-2 enforces Normal-WB and Device-nGnRE
163 #define MT_S2_FWB_NORMAL 6
164 #define MT_S2_FWB_DEVICE_nGnRE 1
166 #ifdef CONFIG_ARM64_4K_PAGES
167 #define IOREMAP_MAX_ORDER (PUD_SHIFT)
169 #define IOREMAP_MAX_ORDER (PMD_SHIFT)
173 extern u64 vabits_actual;
174 #define VA_START (_VA_START(vabits_actual))
176 #include <linux/bitops.h>
177 #include <linux/mmdebug.h>
179 extern s64 physvirt_offset;
180 extern s64 memstart_addr;
181 /* PHYS_OFFSET - the physical address of the start of memory. */
182 #define PHYS_OFFSET ({ VM_BUG_ON(memstart_addr & 1); memstart_addr; })
184 /* the virtual base of the kernel image (minus TEXT_OFFSET) */
185 extern u64 kimage_vaddr;
187 /* the offset between the kernel virtual and physical mappings */
188 extern u64 kimage_voffset;
190 static inline unsigned long kaslr_offset(void)
192 return kimage_vaddr - KIMAGE_VADDR;
196 * Allow all memory at the discovery stage. We will clip it later.
198 #define MIN_MEMBLOCK_ADDR 0
199 #define MAX_MEMBLOCK_ADDR U64_MAX
202 * PFNs are used to describe any physical page; this means
203 * PFN 0 == physical address 0.
205 * This is the PFN of the first RAM page in the kernel
206 * direct-mapped view. We assume this is the first page
207 * of RAM in the mem_map as well.
209 #define PHYS_PFN_OFFSET (PHYS_OFFSET >> PAGE_SHIFT)
212 * When dealing with data aborts, watchpoints, or instruction traps we may end
213 * up with a tagged userland pointer. Clear the tag to get a sane pointer to
214 * pass on to access_ok(), for instance.
216 #define untagged_addr(addr) \
217 ((__typeof__(addr))sign_extend64((u64)(addr), 55))
219 #ifdef CONFIG_KASAN_SW_TAGS
220 #define __tag_shifted(tag) ((u64)(tag) << 56)
221 #define __tag_reset(addr) untagged_addr(addr)
222 #define __tag_get(addr) (__u8)((u64)(addr) >> 56)
224 #define __tag_shifted(tag) 0UL
225 #define __tag_reset(addr) (addr)
226 #define __tag_get(addr) 0
229 static inline const void *__tag_set(const void *addr, u8 tag)
231 u64 __addr = (u64)addr & ~__tag_shifted(0xff);
232 return (const void *)(__addr | __tag_shifted(tag));
236 * Physical vs virtual RAM address space conversion. These are
237 * private definitions which should NOT be used outside memory.h
238 * files. Use virt_to_phys/phys_to_virt/__pa/__va instead.
243 * The linear kernel range starts at the bottom of the virtual address
244 * space. Testing the top bit for the start of the region is a
245 * sufficient check and avoids having to worry about the tag.
247 #define __is_lm_address(addr) (!(((u64)addr) & BIT(vabits_actual - 1)))
249 #define __lm_to_phys(addr) (((addr) + physvirt_offset))
250 #define __kimg_to_phys(addr) ((addr) - kimage_voffset)
252 #define __virt_to_phys_nodebug(x) ({ \
253 phys_addr_t __x = (phys_addr_t)(__tag_reset(x)); \
254 __is_lm_address(__x) ? __lm_to_phys(__x) : \
255 __kimg_to_phys(__x); \
258 #define __pa_symbol_nodebug(x) __kimg_to_phys((phys_addr_t)(x))
260 #ifdef CONFIG_DEBUG_VIRTUAL
261 extern phys_addr_t __virt_to_phys(unsigned long x);
262 extern phys_addr_t __phys_addr_symbol(unsigned long x);
264 #define __virt_to_phys(x) __virt_to_phys_nodebug(x)
265 #define __phys_addr_symbol(x) __pa_symbol_nodebug(x)
268 #define __phys_to_virt(x) ((unsigned long)((x) - physvirt_offset))
269 #define __phys_to_kimg(x) ((unsigned long)((x) + kimage_voffset))
272 * Convert a page to/from a physical address
274 #define page_to_phys(page) (__pfn_to_phys(page_to_pfn(page)))
275 #define phys_to_page(phys) (pfn_to_page(__phys_to_pfn(phys)))
278 * Note: Drivers should NOT use these. They are the wrong
279 * translation for translating DMA addresses. Use the driver
280 * DMA support - see dma-mapping.h.
282 #define virt_to_phys virt_to_phys
283 static inline phys_addr_t virt_to_phys(const volatile void *x)
285 return __virt_to_phys((unsigned long)(x));
288 #define phys_to_virt phys_to_virt
289 static inline void *phys_to_virt(phys_addr_t x)
291 return (void *)(__phys_to_virt(x));
295 * Drivers should NOT use these either.
297 #define __pa(x) __virt_to_phys((unsigned long)(x))
298 #define __pa_symbol(x) __phys_addr_symbol(RELOC_HIDE((unsigned long)(x), 0))
299 #define __pa_nodebug(x) __virt_to_phys_nodebug((unsigned long)(x))
300 #define __va(x) ((void *)__phys_to_virt((phys_addr_t)(x)))
301 #define pfn_to_kaddr(pfn) __va((pfn) << PAGE_SHIFT)
302 #define virt_to_pfn(x) __phys_to_pfn(__virt_to_phys((unsigned long)(x)))
303 #define sym_to_pfn(x) __phys_to_pfn(__pa_symbol(x))
306 * virt_to_page(k) convert a _valid_ virtual address to struct page *
307 * virt_addr_valid(k) indicates whether a virtual address is valid
309 #define ARCH_PFN_OFFSET ((unsigned long)PHYS_PFN_OFFSET)
311 #if !defined(CONFIG_SPARSEMEM_VMEMMAP) || defined(CONFIG_DEBUG_VIRTUAL)
312 #define virt_to_page(kaddr) pfn_to_page(virt_to_pfn(kaddr))
314 #define page_to_virt(x) ({ \
315 __typeof__(x) __page = x; \
316 u64 __idx = ((u64)__page - VMEMMAP_START) / sizeof(struct page);\
317 u64 __addr = PAGE_OFFSET + (__idx * PAGE_SIZE); \
318 (void *)__tag_set((const void *)__addr, page_kasan_tag(__page));\
321 #define virt_to_page(x) ({ \
322 u64 __idx = (__tag_reset((u64)x) - PAGE_OFFSET) / PAGE_SIZE; \
323 u64 __addr = VMEMMAP_START + (__idx * sizeof(struct page)); \
324 (struct page *)__addr; \
328 #define virt_addr_valid(addr) ({ \
329 __typeof__(addr) __addr = addr; \
330 __is_lm_address(__addr) && pfn_valid(virt_to_pfn(__addr)); \
336 * Given that the GIC architecture permits ITS implementations that can only be
337 * configured with a LPI table address once, GICv3 systems with many CPUs may
338 * end up reserving a lot of different regions after a kexec for their LPI
339 * tables (one per CPU), as we are forced to reuse the same memory after kexec
340 * (and thus reserve it persistently with EFI beforehand)
342 #if defined(CONFIG_EFI) && defined(CONFIG_ARM_GIC_V3_ITS)
343 # define INIT_MEMBLOCK_RESERVED_REGIONS (INIT_MEMBLOCK_REGIONS + NR_CPUS + 1)
346 #include <asm-generic/memory_model.h>