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 when HCR_EL2.FWB=0. See R_HMNDG, 179 * R_TNHFM, R_GQFSF and I_MCQKW for the details on how these attributes get 180 * combined with Stage-1. 181 */ 182 #define MT_S2_NORMAL 0xf 183 #define MT_S2_NORMAL_NC 0x5 184 #define MT_S2_DEVICE_nGnRE 0x1 185 #define MT_S2_AS_S1 MT_S2_NORMAL 186 187 /* 188 * Memory types for Stage-2 translation when HCR_EL2.FWB=1. Stage-2 enforces 189 * Normal-WB and Device-nGnRE, unless we actively say that S1 wins. See 190 * R_VRJSW and R_RHWZM for details. 191 */ 192 #define MT_S2_FWB_NORMAL 6 193 #define MT_S2_FWB_NORMAL_NC 5 194 #define MT_S2_FWB_DEVICE_nGnRE 1 195 #define MT_S2_FWB_AS_S1 7 196 197 #ifdef CONFIG_ARM64_4K_PAGES 198 #define IOREMAP_MAX_ORDER (PUD_SHIFT) 199 #else 200 #define IOREMAP_MAX_ORDER (PMD_SHIFT) 201 #endif 202 203 /* 204 * Open-coded (swapper_pg_dir - reserved_pg_dir) as this cannot be calculated 205 * until link time. 206 */ 207 #define RESERVED_SWAPPER_OFFSET (PAGE_SIZE) 208 209 /* 210 * Open-coded (swapper_pg_dir - tramp_pg_dir) as this cannot be calculated 211 * until link time. 212 */ 213 #define TRAMP_SWAPPER_OFFSET (2 * PAGE_SIZE) 214 215 #ifndef __ASSEMBLER__ 216 217 #include <linux/bitops.h> 218 #include <linux/compiler.h> 219 #include <linux/mmdebug.h> 220 #include <linux/types.h> 221 #include <asm/boot.h> 222 #include <asm/bug.h> 223 #include <asm/sections.h> 224 #include <asm/sysreg.h> 225 226 static inline u64 __pure read_tcr(void) 227 { 228 u64 tcr; 229 230 // read_sysreg() uses asm volatile, so avoid it here 231 asm("mrs %0, tcr_el1" : "=r"(tcr)); 232 return tcr; 233 } 234 235 #if VA_BITS > 48 236 // For reasons of #include hell, we can't use TCR_T1SZ_OFFSET/TCR_T1SZ_MASK here 237 #define vabits_actual (64 - ((read_tcr() >> 16) & 63)) 238 #else 239 #define vabits_actual ((u64)VA_BITS) 240 #endif 241 242 extern s64 memstart_addr; 243 /* PHYS_OFFSET - the physical address of the start of memory. */ 244 #define PHYS_OFFSET ({ VM_BUG_ON(memstart_addr & 1); memstart_addr; }) 245 246 /* the offset between the kernel virtual and physical mappings */ 247 extern u64 kimage_voffset; 248 249 static inline unsigned long kaslr_offset(void) 250 { 251 return (u64)&_text - KIMAGE_VADDR; 252 } 253 254 #ifdef CONFIG_RANDOMIZE_BASE 255 void kaslr_init(void); 256 static inline bool kaslr_enabled(void) 257 { 258 extern bool __kaslr_is_enabled; 259 return __kaslr_is_enabled; 260 } 261 #else 262 static inline void kaslr_init(void) { } 263 static inline bool kaslr_enabled(void) { return false; } 264 #endif 265 266 /* 267 * Allow all memory at the discovery stage. We will clip it later. 268 */ 269 #define MIN_MEMBLOCK_ADDR 0 270 #define MAX_MEMBLOCK_ADDR U64_MAX 271 272 /* 273 * PFNs are used to describe any physical page; this means 274 * PFN 0 == physical address 0. 275 * 276 * This is the PFN of the first RAM page in the kernel 277 * direct-mapped view. We assume this is the first page 278 * of RAM in the mem_map as well. 279 */ 280 #define PHYS_PFN_OFFSET (PHYS_OFFSET >> PAGE_SHIFT) 281 282 /* 283 * When dealing with data aborts, watchpoints, or instruction traps we may end 284 * up with a tagged userland pointer. Clear the tag to get a sane pointer to 285 * pass on to access_ok(), for instance. 286 */ 287 #define __untagged_addr(addr) \ 288 ((__force __typeof__(addr))sign_extend64((__force u64)(addr), 55)) 289 290 #define untagged_addr(addr) ({ \ 291 u64 __addr = (__force u64)(addr); \ 292 __addr &= __untagged_addr(__addr); \ 293 (__force __typeof__(addr))__addr; \ 294 }) 295 296 #if defined(CONFIG_KASAN_SW_TAGS) || defined(CONFIG_KASAN_HW_TAGS) 297 #define __tag_shifted(tag) ((u64)(tag) << 56) 298 #define __tag_reset(addr) __untagged_addr(addr) 299 #define __tag_get(addr) (__u8)((u64)(addr) >> 56) 300 #else 301 #define __tag_shifted(tag) 0UL 302 #define __tag_reset(addr) (addr) 303 #define __tag_get(addr) 0 304 #endif /* CONFIG_KASAN_SW_TAGS || CONFIG_KASAN_HW_TAGS */ 305 306 static inline const void *__tag_set(const void *addr, u8 tag) 307 { 308 u64 __addr = (u64)addr & ~__tag_shifted(0xff); 309 return (const void *)(__addr | __tag_shifted(tag)); 310 } 311 312 #ifdef CONFIG_KASAN_HW_TAGS 313 #define arch_enable_tag_checks_sync() mte_enable_kernel_sync() 314 #define arch_enable_tag_checks_async() mte_enable_kernel_async() 315 #define arch_enable_tag_checks_asymm() mte_enable_kernel_asymm() 316 #define arch_enable_tag_checks_write_only() mte_enable_kernel_store_only() 317 #define arch_suppress_tag_checks_start() mte_enable_tco() 318 #define arch_suppress_tag_checks_stop() mte_disable_tco() 319 #define arch_force_async_tag_fault() mte_check_tfsr_exit() 320 #define arch_get_random_tag() mte_get_random_tag() 321 #define arch_get_mem_tag(addr) mte_get_mem_tag(addr) 322 #define arch_set_mem_tag_range(addr, size, tag, init) \ 323 mte_set_mem_tag_range((addr), (size), (tag), (init)) 324 #endif /* CONFIG_KASAN_HW_TAGS */ 325 326 /* 327 * Physical vs virtual RAM address space conversion. These are 328 * private definitions which should NOT be used outside memory.h 329 * files. Use virt_to_phys/phys_to_virt/__pa/__va instead. 330 */ 331 332 333 /* 334 * Check whether an arbitrary address is within the linear map, which 335 * lives in the [PAGE_OFFSET, PAGE_END) interval at the bottom of the 336 * kernel's TTBR1 address range. 337 */ 338 #define __is_lm_address(addr) (((u64)(addr) - PAGE_OFFSET) < (PAGE_END - PAGE_OFFSET)) 339 340 #define __lm_to_phys(addr) (((addr) - PAGE_OFFSET) + PHYS_OFFSET) 341 #define __kimg_to_phys(addr) ((addr) - kimage_voffset) 342 343 #define __virt_to_phys_nodebug(x) ({ \ 344 phys_addr_t __x = (phys_addr_t)(__tag_reset(x)); \ 345 __is_lm_address(__x) ? __lm_to_phys(__x) : __kimg_to_phys(__x); \ 346 }) 347 348 #define __pa_symbol_nodebug(x) __kimg_to_phys((phys_addr_t)(x)) 349 350 #ifdef CONFIG_DEBUG_VIRTUAL 351 extern phys_addr_t __virt_to_phys(unsigned long x); 352 extern phys_addr_t __phys_addr_symbol(unsigned long x); 353 #else 354 #define __virt_to_phys(x) __virt_to_phys_nodebug(x) 355 #define __phys_addr_symbol(x) __pa_symbol_nodebug(x) 356 #endif /* CONFIG_DEBUG_VIRTUAL */ 357 358 #define __phys_to_virt(x) ((unsigned long)((x) - PHYS_OFFSET) | PAGE_OFFSET) 359 #define __phys_to_kimg(x) ((unsigned long)((x) + kimage_voffset)) 360 361 /* 362 * Note: Drivers should NOT use these. They are the wrong 363 * translation for translating DMA addresses. Use the driver 364 * DMA support - see dma-mapping.h. 365 */ 366 #define virt_to_phys virt_to_phys 367 static inline phys_addr_t virt_to_phys(const volatile void *x) 368 { 369 return __virt_to_phys((unsigned long)(x)); 370 } 371 372 #define phys_to_virt phys_to_virt 373 static inline void *phys_to_virt(phys_addr_t x) 374 { 375 return (void *)(__phys_to_virt(x)); 376 } 377 378 /* Needed already here for resolving __phys_to_pfn() in virt_to_pfn() */ 379 #include <asm-generic/memory_model.h> 380 381 static inline unsigned long virt_to_pfn(const void *kaddr) 382 { 383 return __phys_to_pfn(virt_to_phys(kaddr)); 384 } 385 386 /* 387 * Drivers should NOT use these either. 388 */ 389 #define __pa(x) __virt_to_phys((unsigned long)(x)) 390 #define __pa_symbol(x) __phys_addr_symbol(RELOC_HIDE((unsigned long)(x), 0)) 391 #define __pa_nodebug(x) __virt_to_phys_nodebug((unsigned long)(x)) 392 #define __va(x) ((void *)__phys_to_virt((phys_addr_t)(x))) 393 #define pfn_to_kaddr(pfn) __va((pfn) << PAGE_SHIFT) 394 #define sym_to_pfn(x) __phys_to_pfn(__pa_symbol(x)) 395 396 /* 397 * virt_to_page(x) convert a _valid_ virtual address to struct page * 398 * virt_addr_valid(x) indicates whether a virtual address is valid 399 */ 400 401 #if defined(CONFIG_DEBUG_VIRTUAL) 402 #define page_to_virt(x) ({ \ 403 __typeof__(x) __page = x; \ 404 void *__addr = __va(page_to_phys(__page)); \ 405 (void *)__tag_set((const void *)__addr, page_kasan_tag(__page));\ 406 }) 407 #define virt_to_page(x) pfn_to_page(virt_to_pfn(x)) 408 #else 409 #define page_to_virt(x) ({ \ 410 __typeof__(x) __page = x; \ 411 u64 __idx = ((u64)__page - VMEMMAP_START) / sizeof(struct page);\ 412 u64 __addr = PAGE_OFFSET + (__idx * PAGE_SIZE); \ 413 (void *)__tag_set((const void *)__addr, page_kasan_tag(__page));\ 414 }) 415 416 #define virt_to_page(x) ({ \ 417 u64 __idx = (__tag_reset((u64)x) - PAGE_OFFSET) / PAGE_SIZE; \ 418 u64 __addr = VMEMMAP_START + (__idx * sizeof(struct page)); \ 419 (struct page *)__addr; \ 420 }) 421 #endif /* CONFIG_DEBUG_VIRTUAL */ 422 423 #define virt_addr_valid(addr) ({ \ 424 __typeof__(addr) __addr = __tag_reset(addr); \ 425 __is_lm_address(__addr) && pfn_is_map_memory(virt_to_pfn(__addr)); \ 426 }) 427 428 void dump_mem_limit(void); 429 #endif /* !__ASSEMBLER__ */ 430 431 /* 432 * Given that the GIC architecture permits ITS implementations that can only be 433 * configured with a LPI table address once, GICv3 systems with many CPUs may 434 * end up reserving a lot of different regions after a kexec for their LPI 435 * tables (one per CPU), as we are forced to reuse the same memory after kexec 436 * (and thus reserve it persistently with EFI beforehand) 437 */ 438 #if defined(CONFIG_EFI) && defined(CONFIG_ARM_GIC_V3_ITS) 439 # define INIT_MEMBLOCK_RESERVED_REGIONS (INIT_MEMBLOCK_REGIONS + NR_CPUS + 1) 440 #endif 441 442 /* 443 * memory regions which marked with flag MEMBLOCK_NOMAP(for example, the memory 444 * of the EFI_UNUSABLE_MEMORY type) may divide a continuous memory block into 445 * multiple parts. As a result, the number of memory regions is large. 446 */ 447 #ifdef CONFIG_EFI 448 #define INIT_MEMBLOCK_MEMORY_REGIONS (INIT_MEMBLOCK_REGIONS * 8) 449 #endif 450 451 452 #endif /* __ASM_MEMORY_H */ 453