1 /* SPDX-License-Identifier: GPL-2.0-only */ 2 /* 3 * Based on arch/arm/include/asm/processor.h 4 * 5 * Copyright (C) 1995-1999 Russell King 6 * Copyright (C) 2012 ARM Ltd. 7 */ 8 #ifndef __ASM_PROCESSOR_H 9 #define __ASM_PROCESSOR_H 10 11 /* 12 * On arm64 systems, unaligned accesses by the CPU are cheap, and so there is 13 * no point in shifting all network buffers by 2 bytes just to make some IP 14 * header fields appear aligned in memory, potentially sacrificing some DMA 15 * performance on some platforms. 16 */ 17 #define NET_IP_ALIGN 0 18 19 #define MTE_CTRL_GCR_USER_EXCL_SHIFT 0 20 #define MTE_CTRL_GCR_USER_EXCL_MASK 0xffff 21 22 #define MTE_CTRL_TCF_SYNC (1UL << 16) 23 #define MTE_CTRL_TCF_ASYNC (1UL << 17) 24 #define MTE_CTRL_TCF_ASYMM (1UL << 18) 25 26 #define MTE_CTRL_STORE_ONLY (1UL << 19) 27 28 #ifndef __ASSEMBLER__ 29 30 #include <linux/build_bug.h> 31 #include <linux/cache.h> 32 #include <linux/init.h> 33 #include <linux/stddef.h> 34 #include <linux/string.h> 35 #include <linux/thread_info.h> 36 37 #include <vdso/processor.h> 38 39 #include <asm/alternative.h> 40 #include <asm/cpufeature.h> 41 #include <asm/hw_breakpoint.h> 42 #include <asm/kasan.h> 43 #include <asm/lse.h> 44 #include <asm/pgtable-hwdef.h> 45 #include <asm/pointer_auth.h> 46 #include <asm/ptrace.h> 47 #include <asm/spectre.h> 48 #include <asm/types.h> 49 50 /* 51 * TASK_SIZE - the maximum size of a user space task. 52 * TASK_UNMAPPED_BASE - the lower boundary of the mmap VM area. 53 */ 54 55 #define DEFAULT_MAP_WINDOW_64 (UL(1) << VA_BITS_MIN) 56 #define TASK_SIZE_64 (UL(1) << vabits_actual) 57 #define TASK_SIZE_MAX (UL(1) << VA_BITS) 58 59 #ifdef CONFIG_COMPAT 60 #if defined(CONFIG_ARM64_64K_PAGES) && defined(CONFIG_KUSER_HELPERS) 61 /* 62 * With CONFIG_ARM64_64K_PAGES enabled, the last page is occupied 63 * by the compat vectors page. 64 */ 65 #define TASK_SIZE_32 UL(0x100000000) 66 #else 67 #define TASK_SIZE_32 (UL(0x100000000) - PAGE_SIZE) 68 #endif /* CONFIG_ARM64_64K_PAGES */ 69 #define TASK_SIZE (test_thread_flag(TIF_32BIT) ? \ 70 TASK_SIZE_32 : TASK_SIZE_64) 71 #define TASK_SIZE_OF(tsk) (test_tsk_thread_flag(tsk, TIF_32BIT) ? \ 72 TASK_SIZE_32 : TASK_SIZE_64) 73 #define DEFAULT_MAP_WINDOW (test_thread_flag(TIF_32BIT) ? \ 74 TASK_SIZE_32 : DEFAULT_MAP_WINDOW_64) 75 #else 76 #define TASK_SIZE TASK_SIZE_64 77 #define DEFAULT_MAP_WINDOW DEFAULT_MAP_WINDOW_64 78 #endif /* CONFIG_COMPAT */ 79 80 #ifdef CONFIG_ARM64_FORCE_52BIT 81 #define STACK_TOP_MAX TASK_SIZE_64 82 #define TASK_UNMAPPED_BASE (PAGE_ALIGN(TASK_SIZE / 4)) 83 #else 84 #define STACK_TOP_MAX DEFAULT_MAP_WINDOW_64 85 #define TASK_UNMAPPED_BASE (PAGE_ALIGN(DEFAULT_MAP_WINDOW / 4)) 86 #endif /* CONFIG_ARM64_FORCE_52BIT */ 87 88 #ifdef CONFIG_COMPAT 89 #define AARCH32_VECTORS_BASE 0xffff0000 90 #define STACK_TOP (test_thread_flag(TIF_32BIT) ? \ 91 AARCH32_VECTORS_BASE : STACK_TOP_MAX) 92 #else 93 #define STACK_TOP STACK_TOP_MAX 94 #endif /* CONFIG_COMPAT */ 95 96 #ifndef CONFIG_ARM64_FORCE_52BIT 97 #define arch_get_mmap_end(addr, len, flags) \ 98 (((addr) > DEFAULT_MAP_WINDOW) ? TASK_SIZE : DEFAULT_MAP_WINDOW) 99 100 #define arch_get_mmap_base(addr, base) ((addr > DEFAULT_MAP_WINDOW) ? \ 101 base + TASK_SIZE - DEFAULT_MAP_WINDOW :\ 102 base) 103 #endif /* CONFIG_ARM64_FORCE_52BIT */ 104 105 extern phys_addr_t arm64_dma_phys_limit; 106 #define ARCH_LOW_ADDRESS_LIMIT (arm64_dma_phys_limit - 1) 107 108 struct debug_info { 109 #ifdef CONFIG_HAVE_HW_BREAKPOINT 110 /* Have we suspended stepping by a debugger? */ 111 int suspended_step; 112 /* Allow breakpoints and watchpoints to be disabled for this thread. */ 113 int bps_disabled; 114 int wps_disabled; 115 /* Hardware breakpoints pinned to this task. */ 116 struct perf_event *hbp_break[ARM_MAX_BRP]; 117 struct perf_event *hbp_watch[ARM_MAX_WRP]; 118 #endif 119 }; 120 121 enum vec_type { 122 ARM64_VEC_SVE = 0, 123 ARM64_VEC_SME, 124 ARM64_VEC_MAX, 125 }; 126 127 enum fp_type { 128 FP_STATE_CURRENT, /* Save based on current task state. */ 129 FP_STATE_FPSIMD, 130 FP_STATE_SVE, 131 }; 132 133 struct cpu_context { 134 unsigned long x19; 135 unsigned long x20; 136 unsigned long x21; 137 unsigned long x22; 138 unsigned long x23; 139 unsigned long x24; 140 unsigned long x25; 141 unsigned long x26; 142 unsigned long x27; 143 unsigned long x28; 144 unsigned long fp; 145 unsigned long sp; 146 unsigned long pc; 147 }; 148 149 struct thread_struct { 150 struct cpu_context cpu_context; /* cpu context */ 151 152 /* 153 * Whitelisted fields for hardened usercopy: 154 * Maintainers must ensure manually that this contains no 155 * implicit padding. 156 */ 157 struct { 158 unsigned long tp_value; /* TLS register */ 159 unsigned long tp2_value; 160 u64 fpmr; 161 unsigned long pad; 162 struct user_fpsimd_state fpsimd_state; 163 } uw; 164 165 enum fp_type fp_type; /* registers FPSIMD or SVE? */ 166 unsigned int fpsimd_cpu; 167 void *sve_state; /* SVE registers, if any */ 168 void *sme_state; /* ZA and ZT state, if any */ 169 unsigned int vl[ARM64_VEC_MAX]; /* vector length */ 170 unsigned int vl_onexec[ARM64_VEC_MAX]; /* vl after next exec */ 171 unsigned long fault_address; /* fault info */ 172 unsigned long fault_code; /* ESR_EL1 value */ 173 struct debug_info debug; /* debugging */ 174 175 /* 176 * Set [cleared] by kernel_neon_begin() [kernel_neon_end()] to the 177 * address of a caller provided buffer that will be used to preserve a 178 * task's kernel mode FPSIMD state while it is scheduled out. 179 */ 180 struct user_fpsimd_state *kernel_fpsimd_state; 181 unsigned int kernel_fpsimd_cpu; 182 #ifdef CONFIG_ARM64_PTR_AUTH 183 struct ptrauth_keys_user keys_user; 184 #ifdef CONFIG_ARM64_PTR_AUTH_KERNEL 185 struct ptrauth_keys_kernel keys_kernel; 186 #endif 187 #endif 188 #ifdef CONFIG_ARM64_MTE 189 u64 mte_ctrl; 190 #endif 191 u64 sctlr_user; 192 u64 svcr; 193 u64 tpidr2_el0; 194 u64 por_el0; 195 #ifdef CONFIG_ARM64_GCS 196 unsigned int gcs_el0_mode; 197 unsigned int gcs_el0_locked; 198 u64 gcspr_el0; 199 u64 gcs_base; 200 u64 gcs_size; 201 #endif 202 }; 203 204 static inline unsigned int thread_get_vl(struct thread_struct *thread, 205 enum vec_type type) 206 { 207 return thread->vl[type]; 208 } 209 210 static inline unsigned int thread_get_sve_vl(struct thread_struct *thread) 211 { 212 return thread_get_vl(thread, ARM64_VEC_SVE); 213 } 214 215 static inline unsigned int thread_get_sme_vl(struct thread_struct *thread) 216 { 217 return thread_get_vl(thread, ARM64_VEC_SME); 218 } 219 220 static inline unsigned int thread_get_cur_vl(struct thread_struct *thread) 221 { 222 if (system_supports_sme() && (thread->svcr & SVCR_SM_MASK)) 223 return thread_get_sme_vl(thread); 224 else 225 return thread_get_sve_vl(thread); 226 } 227 228 unsigned int task_get_vl(const struct task_struct *task, enum vec_type type); 229 void task_set_vl(struct task_struct *task, enum vec_type type, 230 unsigned long vl); 231 void task_set_vl_onexec(struct task_struct *task, enum vec_type type, 232 unsigned long vl); 233 unsigned int task_get_vl_onexec(const struct task_struct *task, 234 enum vec_type type); 235 236 static inline unsigned int task_get_sve_vl(const struct task_struct *task) 237 { 238 return task_get_vl(task, ARM64_VEC_SVE); 239 } 240 241 static inline unsigned int task_get_sme_vl(const struct task_struct *task) 242 { 243 return task_get_vl(task, ARM64_VEC_SME); 244 } 245 246 static inline void task_set_sve_vl(struct task_struct *task, unsigned long vl) 247 { 248 task_set_vl(task, ARM64_VEC_SVE, vl); 249 } 250 251 static inline unsigned int task_get_sve_vl_onexec(const struct task_struct *task) 252 { 253 return task_get_vl_onexec(task, ARM64_VEC_SVE); 254 } 255 256 static inline void task_set_sve_vl_onexec(struct task_struct *task, 257 unsigned long vl) 258 { 259 task_set_vl_onexec(task, ARM64_VEC_SVE, vl); 260 } 261 262 #define SCTLR_USER_MASK \ 263 (SCTLR_ELx_ENIA | SCTLR_ELx_ENIB | SCTLR_ELx_ENDA | SCTLR_ELx_ENDB | \ 264 SCTLR_EL1_TCF0_MASK) 265 266 static inline void arch_thread_struct_whitelist(unsigned long *offset, 267 unsigned long *size) 268 { 269 /* Verify that there is no padding among the whitelisted fields: */ 270 BUILD_BUG_ON(sizeof_field(struct thread_struct, uw) != 271 sizeof_field(struct thread_struct, uw.tp_value) + 272 sizeof_field(struct thread_struct, uw.tp2_value) + 273 sizeof_field(struct thread_struct, uw.fpmr) + 274 sizeof_field(struct thread_struct, uw.pad) + 275 sizeof_field(struct thread_struct, uw.fpsimd_state)); 276 277 *offset = offsetof(struct thread_struct, uw); 278 *size = sizeof_field(struct thread_struct, uw); 279 } 280 281 #ifdef CONFIG_COMPAT 282 #define task_user_tls(t) \ 283 ({ \ 284 unsigned long *__tls; \ 285 if (is_compat_thread(task_thread_info(t))) \ 286 __tls = &(t)->thread.uw.tp2_value; \ 287 else \ 288 __tls = &(t)->thread.uw.tp_value; \ 289 __tls; \ 290 }) 291 #else 292 #define task_user_tls(t) (&(t)->thread.uw.tp_value) 293 #endif 294 295 /* Sync TPIDR_EL0 back to thread_struct for current */ 296 void tls_preserve_current_state(void); 297 298 #define INIT_THREAD { \ 299 .fpsimd_cpu = NR_CPUS, \ 300 } 301 302 static inline void start_thread_common(struct pt_regs *regs, unsigned long pc, 303 unsigned long pstate) 304 { 305 /* 306 * Ensure all GPRs are zeroed, and initialize PC + PSTATE. 307 * The SP (or compat SP) will be initialized later. 308 */ 309 regs->user_regs = (struct user_pt_regs) { 310 .pc = pc, 311 .pstate = pstate, 312 }; 313 314 /* 315 * To allow the syscalls:sys_exit_execve tracepoint we need to preserve 316 * syscallno, but do not need orig_x0 or the original GPRs. 317 */ 318 regs->orig_x0 = 0; 319 320 /* 321 * An exec from a kernel thread won't have an existing PMR value. 322 */ 323 if (system_uses_irq_prio_masking()) 324 regs->pmr = GIC_PRIO_IRQON; 325 326 /* 327 * The pt_regs::stackframe field must remain valid throughout this 328 * function as a stacktrace can be taken at any time. Any user or 329 * kernel task should have a valid final frame. 330 */ 331 WARN_ON_ONCE(regs->stackframe.record.fp != 0); 332 WARN_ON_ONCE(regs->stackframe.record.lr != 0); 333 WARN_ON_ONCE(regs->stackframe.type != FRAME_META_TYPE_FINAL); 334 } 335 336 static inline void start_thread(struct pt_regs *regs, unsigned long pc, 337 unsigned long sp) 338 { 339 start_thread_common(regs, pc, PSR_MODE_EL0t); 340 spectre_v4_enable_task_mitigation(current); 341 regs->sp = sp; 342 } 343 344 #ifdef CONFIG_COMPAT 345 static inline void compat_start_thread(struct pt_regs *regs, unsigned long pc, 346 unsigned long sp) 347 { 348 unsigned long pstate = PSR_AA32_MODE_USR; 349 if (pc & 1) 350 pstate |= PSR_AA32_T_BIT; 351 if (IS_ENABLED(CONFIG_CPU_BIG_ENDIAN)) 352 pstate |= PSR_AA32_E_BIT; 353 354 start_thread_common(regs, pc, pstate); 355 spectre_v4_enable_task_mitigation(current); 356 regs->compat_sp = sp; 357 } 358 #endif 359 360 static __always_inline bool is_ttbr0_addr(unsigned long addr) 361 { 362 /* entry assembly clears tags for TTBR0 addrs */ 363 return addr < TASK_SIZE; 364 } 365 366 static __always_inline bool is_ttbr1_addr(unsigned long addr) 367 { 368 /* TTBR1 addresses may have a tag if KASAN_SW_TAGS is in use */ 369 return arch_kasan_reset_tag(addr) >= PAGE_OFFSET; 370 } 371 372 /* Forward declaration, a strange C thing */ 373 struct task_struct; 374 375 unsigned long __get_wchan(struct task_struct *p); 376 377 void update_sctlr_el1(u64 sctlr); 378 379 /* Thread switching */ 380 extern struct task_struct *cpu_switch_to(struct task_struct *prev, 381 struct task_struct *next); 382 383 #define task_pt_regs(p) \ 384 ((struct pt_regs *)(THREAD_SIZE + task_stack_page(p)) - 1) 385 386 #define KSTK_EIP(tsk) ((unsigned long)task_pt_regs(tsk)->pc) 387 #define KSTK_ESP(tsk) user_stack_pointer(task_pt_regs(tsk)) 388 389 /* 390 * Prefetching support 391 */ 392 #define ARCH_HAS_PREFETCH 393 static inline void prefetch(const void *ptr) 394 { 395 asm volatile("prfm pldl1keep, %a0\n" : : "p" (ptr)); 396 } 397 398 #define ARCH_HAS_PREFETCHW 399 static inline void prefetchw(const void *ptr) 400 { 401 asm volatile("prfm pstl1keep, %a0\n" : : "p" (ptr)); 402 } 403 404 extern unsigned long __ro_after_init signal_minsigstksz; /* sigframe size */ 405 extern void __init minsigstksz_setup(void); 406 407 /* 408 * Not at the top of the file due to a direct #include cycle between 409 * <asm/fpsimd.h> and <asm/processor.h>. Deferring this #include 410 * ensures that contents of processor.h are visible to fpsimd.h even if 411 * processor.h is included first. 412 * 413 * These prctl helpers are the only things in this file that require 414 * fpsimd.h. The core code expects them to be in this header. 415 */ 416 #include <asm/fpsimd.h> 417 418 /* Userspace interface for PR_S[MV]E_{SET,GET}_VL prctl()s: */ 419 #define SVE_SET_VL(arg) sve_set_current_vl(arg) 420 #define SVE_GET_VL() sve_get_current_vl() 421 #define SME_SET_VL(arg) sme_set_current_vl(arg) 422 #define SME_GET_VL() sme_get_current_vl() 423 424 /* PR_PAC_RESET_KEYS prctl */ 425 #define PAC_RESET_KEYS(tsk, arg) ptrauth_prctl_reset_keys(tsk, arg) 426 427 /* PR_PAC_{SET,GET}_ENABLED_KEYS prctl */ 428 #define PAC_SET_ENABLED_KEYS(tsk, keys, enabled) \ 429 ptrauth_set_enabled_keys(tsk, keys, enabled) 430 #define PAC_GET_ENABLED_KEYS(tsk) ptrauth_get_enabled_keys(tsk) 431 432 #ifdef CONFIG_ARM64_TAGGED_ADDR_ABI 433 /* PR_{SET,GET}_TAGGED_ADDR_CTRL prctl */ 434 long set_tagged_addr_ctrl(struct task_struct *task, unsigned long arg); 435 long get_tagged_addr_ctrl(struct task_struct *task); 436 #define SET_TAGGED_ADDR_CTRL(arg) set_tagged_addr_ctrl(current, arg) 437 #define GET_TAGGED_ADDR_CTRL() get_tagged_addr_ctrl(current) 438 #endif 439 440 int get_tsc_mode(unsigned long adr); 441 int set_tsc_mode(unsigned int val); 442 #define GET_TSC_CTL(adr) get_tsc_mode((adr)) 443 #define SET_TSC_CTL(val) set_tsc_mode((val)) 444 445 #endif /* __ASSEMBLER__ */ 446 #endif /* __ASM_PROCESSOR_H */ 447