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_RANGE (_PAGE_END(VA_BITS_MIN) - PAGE_OFFSET) 34 #define VMEMMAP_SIZE ((VMEMMAP_RANGE >> PAGE_SHIFT) * sizeof(struct page)) 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 (_PAGE_END(VA_BITS_MIN)) 49 #define MODULES_VSIZE (SZ_2G) 50 #define VMEMMAP_START (VMEMMAP_END - VMEMMAP_SIZE) 51 #define VMEMMAP_END (-UL(SZ_1G)) 52 #define PCI_IO_START (VMEMMAP_END + SZ_8M) 53 #define PCI_IO_END (PCI_IO_START + PCI_IO_SIZE) 54 #define FIXADDR_TOP (-UL(SZ_8M)) 55 56 #if VA_BITS > 48 57 #ifdef CONFIG_ARM64_16K_PAGES 58 #define VA_BITS_MIN (47) 59 #else 60 #define VA_BITS_MIN (48) 61 #endif 62 #else 63 #define VA_BITS_MIN (VA_BITS) 64 #endif 65 66 #define _PAGE_END(va) (-(UL(1) << ((va) - 1))) 67 68 #define KERNEL_START _text 69 #define KERNEL_END _end 70 71 /* 72 * Generic and Software Tag-Based KASAN modes require 1/8th and 1/16th of the 73 * kernel virtual address space for storing the shadow memory respectively. 74 * 75 * The mapping between a virtual memory address and its corresponding shadow 76 * memory address is defined based on the formula: 77 * 78 * shadow_addr = (addr >> KASAN_SHADOW_SCALE_SHIFT) + KASAN_SHADOW_OFFSET 79 * 80 * where KASAN_SHADOW_SCALE_SHIFT is the order of the number of bits that map 81 * to a single shadow byte and KASAN_SHADOW_OFFSET is a constant that offsets 82 * the mapping. Note that KASAN_SHADOW_OFFSET does not point to the start of 83 * the shadow memory region. 84 * 85 * Based on this mapping, we define two constants: 86 * 87 * KASAN_SHADOW_START: the start of the shadow memory region; 88 * KASAN_SHADOW_END: the end of the shadow memory region. 89 * 90 * KASAN_SHADOW_END is defined first as the shadow address that corresponds to 91 * the upper bound of possible virtual kernel memory addresses UL(1) << 64 92 * according to the mapping formula. 93 * 94 * KASAN_SHADOW_START is defined second based on KASAN_SHADOW_END. The shadow 95 * memory start must map to the lowest possible kernel virtual memory address 96 * and thus it depends on the actual bitness of the address space. 97 * 98 * As KASAN inserts redzones between stack variables, this increases the stack 99 * memory usage significantly. Thus, we double the (minimum) stack size. 100 */ 101 #if defined(CONFIG_KASAN_GENERIC) || defined(CONFIG_KASAN_SW_TAGS) 102 #define KASAN_SHADOW_OFFSET _AC(CONFIG_KASAN_SHADOW_OFFSET, UL) 103 #define KASAN_SHADOW_END ((UL(1) << (64 - KASAN_SHADOW_SCALE_SHIFT)) + KASAN_SHADOW_OFFSET) 104 #define _KASAN_SHADOW_START(va) (KASAN_SHADOW_END - (UL(1) << ((va) - KASAN_SHADOW_SCALE_SHIFT))) 105 #define KASAN_SHADOW_START _KASAN_SHADOW_START(vabits_actual) 106 #define PAGE_END KASAN_SHADOW_START 107 #define KASAN_THREAD_SHIFT 1 108 #else 109 #define KASAN_THREAD_SHIFT 0 110 #define PAGE_END (_PAGE_END(VA_BITS_MIN)) 111 #endif /* CONFIG_KASAN */ 112 113 #define DIRECT_MAP_PHYSMEM_END __pa(PAGE_END - 1) 114 115 #define MIN_THREAD_SHIFT (14 + KASAN_THREAD_SHIFT) 116 117 /* 118 * VMAP'd stacks are allocated at page granularity, so we must ensure that such 119 * stacks are a multiple of page size. 120 */ 121 #if (MIN_THREAD_SHIFT < PAGE_SHIFT) 122 #define THREAD_SHIFT PAGE_SHIFT 123 #else 124 #define THREAD_SHIFT MIN_THREAD_SHIFT 125 #endif 126 127 #if THREAD_SHIFT >= PAGE_SHIFT 128 #define THREAD_SIZE_ORDER (THREAD_SHIFT - PAGE_SHIFT) 129 #endif 130 131 #define THREAD_SIZE (UL(1) << THREAD_SHIFT) 132 133 /* 134 * By aligning VMAP'd stacks to 2 * THREAD_SIZE, we can detect overflow by 135 * checking sp & (1 << THREAD_SHIFT), which we can do cheaply in the entry 136 * assembly. 137 */ 138 #define THREAD_ALIGN (2 * THREAD_SIZE) 139 140 #define IRQ_STACK_SIZE THREAD_SIZE 141 142 #define OVERFLOW_STACK_SIZE SZ_4K 143 144 #define NVHE_STACK_SHIFT PAGE_SHIFT 145 #define NVHE_STACK_SIZE (UL(1) << NVHE_STACK_SHIFT) 146 147 /* 148 * With the minimum frame size of [x29, x30], exactly half the combined 149 * sizes of the hyp and overflow stacks is the maximum size needed to 150 * save the unwinded stacktrace; plus an additional entry to delimit the 151 * end. 152 */ 153 #define NVHE_STACKTRACE_SIZE ((OVERFLOW_STACK_SIZE + NVHE_STACK_SIZE) / 2 + sizeof(long)) 154 155 /* 156 * Alignment of kernel segments (e.g. .text, .data). 157 * 158 * 4 KB granule: 16 level 3 entries, with contiguous bit 159 * 16 KB granule: 4 level 3 entries, without contiguous bit 160 * 64 KB granule: 1 level 3 entry 161 */ 162 #define SEGMENT_ALIGN SZ_64K 163 164 /* 165 * Memory types available. 166 * 167 * IMPORTANT: MT_NORMAL must be index 0 since vm_get_page_prot() may 'or' in 168 * the MT_NORMAL_TAGGED memory type for PROT_MTE mappings. Note 169 * that protection_map[] only contains MT_NORMAL attributes. 170 */ 171 #define MT_NORMAL 0 172 #define MT_NORMAL_TAGGED 1 173 #define MT_NORMAL_NC 2 174 #define MT_DEVICE_nGnRnE 3 175 #define MT_DEVICE_nGnRE 4 176 177 /* 178 * Memory types for Stage-2 translation 179 */ 180 #define MT_S2_NORMAL 0xf 181 #define MT_S2_NORMAL_NC 0x5 182 #define MT_S2_DEVICE_nGnRE 0x1 183 184 /* 185 * Memory types for Stage-2 translation when ID_AA64MMFR2_EL1.FWB is 0001 186 * Stage-2 enforces Normal-WB and Device-nGnRE 187 */ 188 #define MT_S2_FWB_NORMAL 6 189 #define MT_S2_FWB_NORMAL_NC 5 190 #define MT_S2_FWB_DEVICE_nGnRE 1 191 192 #ifdef CONFIG_ARM64_4K_PAGES 193 #define IOREMAP_MAX_ORDER (PUD_SHIFT) 194 #else 195 #define IOREMAP_MAX_ORDER (PMD_SHIFT) 196 #endif 197 198 /* 199 * Open-coded (swapper_pg_dir - reserved_pg_dir) as this cannot be calculated 200 * until link time. 201 */ 202 #define RESERVED_SWAPPER_OFFSET (PAGE_SIZE) 203 204 /* 205 * Open-coded (swapper_pg_dir - tramp_pg_dir) as this cannot be calculated 206 * until link time. 207 */ 208 #define TRAMP_SWAPPER_OFFSET (2 * PAGE_SIZE) 209 210 #ifndef __ASSEMBLY__ 211 212 #include <linux/bitops.h> 213 #include <linux/compiler.h> 214 #include <linux/mmdebug.h> 215 #include <linux/types.h> 216 #include <asm/boot.h> 217 #include <asm/bug.h> 218 #include <asm/sections.h> 219 #include <asm/sysreg.h> 220 221 static inline u64 __pure read_tcr(void) 222 { 223 u64 tcr; 224 225 // read_sysreg() uses asm volatile, so avoid it here 226 asm("mrs %0, tcr_el1" : "=r"(tcr)); 227 return tcr; 228 } 229 230 #if VA_BITS > 48 231 // For reasons of #include hell, we can't use TCR_T1SZ_OFFSET/TCR_T1SZ_MASK here 232 #define vabits_actual (64 - ((read_tcr() >> 16) & 63)) 233 #else 234 #define vabits_actual ((u64)VA_BITS) 235 #endif 236 237 extern s64 memstart_addr; 238 /* PHYS_OFFSET - the physical address of the start of memory. */ 239 #define PHYS_OFFSET ({ VM_BUG_ON(memstart_addr & 1); memstart_addr; }) 240 241 /* the offset between the kernel virtual and physical mappings */ 242 extern u64 kimage_voffset; 243 244 static inline unsigned long kaslr_offset(void) 245 { 246 return (u64)&_text - KIMAGE_VADDR; 247 } 248 249 #ifdef CONFIG_RANDOMIZE_BASE 250 void kaslr_init(void); 251 static inline bool kaslr_enabled(void) 252 { 253 extern bool __kaslr_is_enabled; 254 return __kaslr_is_enabled; 255 } 256 #else 257 static inline void kaslr_init(void) { } 258 static inline bool kaslr_enabled(void) { return false; } 259 #endif 260 261 /* 262 * Allow all memory at the discovery stage. We will clip it later. 263 */ 264 #define MIN_MEMBLOCK_ADDR 0 265 #define MAX_MEMBLOCK_ADDR U64_MAX 266 267 /* 268 * PFNs are used to describe any physical page; this means 269 * PFN 0 == physical address 0. 270 * 271 * This is the PFN of the first RAM page in the kernel 272 * direct-mapped view. We assume this is the first page 273 * of RAM in the mem_map as well. 274 */ 275 #define PHYS_PFN_OFFSET (PHYS_OFFSET >> PAGE_SHIFT) 276 277 /* 278 * When dealing with data aborts, watchpoints, or instruction traps we may end 279 * up with a tagged userland pointer. Clear the tag to get a sane pointer to 280 * pass on to access_ok(), for instance. 281 */ 282 #define __untagged_addr(addr) \ 283 ((__force __typeof__(addr))sign_extend64((__force u64)(addr), 55)) 284 285 #define untagged_addr(addr) ({ \ 286 u64 __addr = (__force u64)(addr); \ 287 __addr &= __untagged_addr(__addr); \ 288 (__force __typeof__(addr))__addr; \ 289 }) 290 291 #if defined(CONFIG_KASAN_SW_TAGS) || defined(CONFIG_KASAN_HW_TAGS) 292 #define __tag_shifted(tag) ((u64)(tag) << 56) 293 #define __tag_reset(addr) __untagged_addr(addr) 294 #define __tag_get(addr) (__u8)((u64)(addr) >> 56) 295 #else 296 #define __tag_shifted(tag) 0UL 297 #define __tag_reset(addr) (addr) 298 #define __tag_get(addr) 0 299 #endif /* CONFIG_KASAN_SW_TAGS || CONFIG_KASAN_HW_TAGS */ 300 301 static inline const void *__tag_set(const void *addr, u8 tag) 302 { 303 u64 __addr = (u64)addr & ~__tag_shifted(0xff); 304 return (const void *)(__addr | __tag_shifted(tag)); 305 } 306 307 #ifdef CONFIG_KASAN_HW_TAGS 308 #define arch_enable_tag_checks_sync() mte_enable_kernel_sync() 309 #define arch_enable_tag_checks_async() mte_enable_kernel_async() 310 #define arch_enable_tag_checks_asymm() mte_enable_kernel_asymm() 311 #define arch_suppress_tag_checks_start() mte_enable_tco() 312 #define arch_suppress_tag_checks_stop() mte_disable_tco() 313 #define arch_force_async_tag_fault() mte_check_tfsr_exit() 314 #define arch_get_random_tag() mte_get_random_tag() 315 #define arch_get_mem_tag(addr) mte_get_mem_tag(addr) 316 #define arch_set_mem_tag_range(addr, size, tag, init) \ 317 mte_set_mem_tag_range((addr), (size), (tag), (init)) 318 #endif /* CONFIG_KASAN_HW_TAGS */ 319 320 /* 321 * Physical vs virtual RAM address space conversion. These are 322 * private definitions which should NOT be used outside memory.h 323 * files. Use virt_to_phys/phys_to_virt/__pa/__va instead. 324 */ 325 326 327 /* 328 * Check whether an arbitrary address is within the linear map, which 329 * lives in the [PAGE_OFFSET, PAGE_END) interval at the bottom of the 330 * kernel's TTBR1 address range. 331 */ 332 #define __is_lm_address(addr) (((u64)(addr) - PAGE_OFFSET) < (PAGE_END - PAGE_OFFSET)) 333 334 #define __lm_to_phys(addr) (((addr) - PAGE_OFFSET) + PHYS_OFFSET) 335 #define __kimg_to_phys(addr) ((addr) - kimage_voffset) 336 337 #define __virt_to_phys_nodebug(x) ({ \ 338 phys_addr_t __x = (phys_addr_t)(__tag_reset(x)); \ 339 __is_lm_address(__x) ? __lm_to_phys(__x) : __kimg_to_phys(__x); \ 340 }) 341 342 #define __pa_symbol_nodebug(x) __kimg_to_phys((phys_addr_t)(x)) 343 344 #ifdef CONFIG_DEBUG_VIRTUAL 345 extern phys_addr_t __virt_to_phys(unsigned long x); 346 extern phys_addr_t __phys_addr_symbol(unsigned long x); 347 #else 348 #define __virt_to_phys(x) __virt_to_phys_nodebug(x) 349 #define __phys_addr_symbol(x) __pa_symbol_nodebug(x) 350 #endif /* CONFIG_DEBUG_VIRTUAL */ 351 352 #define __phys_to_virt(x) ((unsigned long)((x) - PHYS_OFFSET) | PAGE_OFFSET) 353 #define __phys_to_kimg(x) ((unsigned long)((x) + kimage_voffset)) 354 355 /* 356 * Note: Drivers should NOT use these. They are the wrong 357 * translation for translating DMA addresses. Use the driver 358 * DMA support - see dma-mapping.h. 359 */ 360 #define virt_to_phys virt_to_phys 361 static inline phys_addr_t virt_to_phys(const volatile void *x) 362 { 363 return __virt_to_phys((unsigned long)(x)); 364 } 365 366 #define phys_to_virt phys_to_virt 367 static inline void *phys_to_virt(phys_addr_t x) 368 { 369 return (void *)(__phys_to_virt(x)); 370 } 371 372 /* Needed already here for resolving __phys_to_pfn() in virt_to_pfn() */ 373 #include <asm-generic/memory_model.h> 374 375 static inline unsigned long virt_to_pfn(const void *kaddr) 376 { 377 return __phys_to_pfn(virt_to_phys(kaddr)); 378 } 379 380 /* 381 * Drivers should NOT use these either. 382 */ 383 #define __pa(x) __virt_to_phys((unsigned long)(x)) 384 #define __pa_symbol(x) __phys_addr_symbol(RELOC_HIDE((unsigned long)(x), 0)) 385 #define __pa_nodebug(x) __virt_to_phys_nodebug((unsigned long)(x)) 386 #define __va(x) ((void *)__phys_to_virt((phys_addr_t)(x))) 387 #define pfn_to_kaddr(pfn) __va((pfn) << PAGE_SHIFT) 388 #define sym_to_pfn(x) __phys_to_pfn(__pa_symbol(x)) 389 390 /* 391 * virt_to_page(x) convert a _valid_ virtual address to struct page * 392 * virt_addr_valid(x) indicates whether a virtual address is valid 393 */ 394 #define ARCH_PFN_OFFSET ((unsigned long)PHYS_PFN_OFFSET) 395 396 #if defined(CONFIG_DEBUG_VIRTUAL) 397 #define page_to_virt(x) ({ \ 398 __typeof__(x) __page = x; \ 399 void *__addr = __va(page_to_phys(__page)); \ 400 (void *)__tag_set((const void *)__addr, page_kasan_tag(__page));\ 401 }) 402 #define virt_to_page(x) pfn_to_page(virt_to_pfn(x)) 403 #else 404 #define page_to_virt(x) ({ \ 405 __typeof__(x) __page = x; \ 406 u64 __idx = ((u64)__page - VMEMMAP_START) / sizeof(struct page);\ 407 u64 __addr = PAGE_OFFSET + (__idx * PAGE_SIZE); \ 408 (void *)__tag_set((const void *)__addr, page_kasan_tag(__page));\ 409 }) 410 411 #define virt_to_page(x) ({ \ 412 u64 __idx = (__tag_reset((u64)x) - PAGE_OFFSET) / PAGE_SIZE; \ 413 u64 __addr = VMEMMAP_START + (__idx * sizeof(struct page)); \ 414 (struct page *)__addr; \ 415 }) 416 #endif /* CONFIG_DEBUG_VIRTUAL */ 417 418 #define virt_addr_valid(addr) ({ \ 419 __typeof__(addr) __addr = __tag_reset(addr); \ 420 __is_lm_address(__addr) && pfn_is_map_memory(virt_to_pfn(__addr)); \ 421 }) 422 423 void dump_mem_limit(void); 424 #endif /* !ASSEMBLY */ 425 426 /* 427 * Given that the GIC architecture permits ITS implementations that can only be 428 * configured with a LPI table address once, GICv3 systems with many CPUs may 429 * end up reserving a lot of different regions after a kexec for their LPI 430 * tables (one per CPU), as we are forced to reuse the same memory after kexec 431 * (and thus reserve it persistently with EFI beforehand) 432 */ 433 #if defined(CONFIG_EFI) && defined(CONFIG_ARM_GIC_V3_ITS) 434 # define INIT_MEMBLOCK_RESERVED_REGIONS (INIT_MEMBLOCK_REGIONS + NR_CPUS + 1) 435 #endif 436 437 /* 438 * memory regions which marked with flag MEMBLOCK_NOMAP(for example, the memory 439 * of the EFI_UNUSABLE_MEMORY type) may divide a continuous memory block into 440 * multiple parts. As a result, the number of memory regions is large. 441 */ 442 #ifdef CONFIG_EFI 443 #define INIT_MEMBLOCK_MEMORY_REGIONS (INIT_MEMBLOCK_REGIONS * 8) 444 #endif 445 446 447 #endif /* __ASM_MEMORY_H */ 448