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 #ifndef __ASSEMBLY__ 27 28 #include <linux/build_bug.h> 29 #include <linux/cache.h> 30 #include <linux/init.h> 31 #include <linux/stddef.h> 32 #include <linux/string.h> 33 #include <linux/thread_info.h> 34 35 #include <vdso/processor.h> 36 37 #include <asm/alternative.h> 38 #include <asm/cpufeature.h> 39 #include <asm/hw_breakpoint.h> 40 #include <asm/kasan.h> 41 #include <asm/lse.h> 42 #include <asm/pgtable-hwdef.h> 43 #include <asm/pointer_auth.h> 44 #include <asm/ptrace.h> 45 #include <asm/spectre.h> 46 #include <asm/types.h> 47 48 /* 49 * TASK_SIZE - the maximum size of a user space task. 50 * TASK_UNMAPPED_BASE - the lower boundary of the mmap VM area. 51 */ 52 53 #define DEFAULT_MAP_WINDOW_64 (UL(1) << VA_BITS_MIN) 54 #define TASK_SIZE_64 (UL(1) << vabits_actual) 55 #define TASK_SIZE_MAX (UL(1) << VA_BITS) 56 57 #ifdef CONFIG_COMPAT 58 #if defined(CONFIG_ARM64_64K_PAGES) && defined(CONFIG_KUSER_HELPERS) 59 /* 60 * With CONFIG_ARM64_64K_PAGES enabled, the last page is occupied 61 * by the compat vectors page. 62 */ 63 #define TASK_SIZE_32 UL(0x100000000) 64 #else 65 #define TASK_SIZE_32 (UL(0x100000000) - PAGE_SIZE) 66 #endif /* CONFIG_ARM64_64K_PAGES */ 67 #define TASK_SIZE (test_thread_flag(TIF_32BIT) ? \ 68 TASK_SIZE_32 : TASK_SIZE_64) 69 #define TASK_SIZE_OF(tsk) (test_tsk_thread_flag(tsk, TIF_32BIT) ? \ 70 TASK_SIZE_32 : TASK_SIZE_64) 71 #define DEFAULT_MAP_WINDOW (test_thread_flag(TIF_32BIT) ? \ 72 TASK_SIZE_32 : DEFAULT_MAP_WINDOW_64) 73 #else 74 #define TASK_SIZE TASK_SIZE_64 75 #define DEFAULT_MAP_WINDOW DEFAULT_MAP_WINDOW_64 76 #endif /* CONFIG_COMPAT */ 77 78 #ifdef CONFIG_ARM64_FORCE_52BIT 79 #define STACK_TOP_MAX TASK_SIZE_64 80 #define TASK_UNMAPPED_BASE (PAGE_ALIGN(TASK_SIZE / 4)) 81 #else 82 #define STACK_TOP_MAX DEFAULT_MAP_WINDOW_64 83 #define TASK_UNMAPPED_BASE (PAGE_ALIGN(DEFAULT_MAP_WINDOW / 4)) 84 #endif /* CONFIG_ARM64_FORCE_52BIT */ 85 86 #ifdef CONFIG_COMPAT 87 #define AARCH32_VECTORS_BASE 0xffff0000 88 #define STACK_TOP (test_thread_flag(TIF_32BIT) ? \ 89 AARCH32_VECTORS_BASE : STACK_TOP_MAX) 90 #else 91 #define STACK_TOP STACK_TOP_MAX 92 #endif /* CONFIG_COMPAT */ 93 94 #ifndef CONFIG_ARM64_FORCE_52BIT 95 #define arch_get_mmap_end(addr, len, flags) \ 96 (((addr) > DEFAULT_MAP_WINDOW) ? TASK_SIZE : DEFAULT_MAP_WINDOW) 97 98 #define arch_get_mmap_base(addr, base) ((addr > DEFAULT_MAP_WINDOW) ? \ 99 base + TASK_SIZE - DEFAULT_MAP_WINDOW :\ 100 base) 101 #endif /* CONFIG_ARM64_FORCE_52BIT */ 102 103 extern phys_addr_t arm64_dma_phys_limit; 104 #define ARCH_LOW_ADDRESS_LIMIT (arm64_dma_phys_limit - 1) 105 106 struct debug_info { 107 #ifdef CONFIG_HAVE_HW_BREAKPOINT 108 /* Have we suspended stepping by a debugger? */ 109 int suspended_step; 110 /* Allow breakpoints and watchpoints to be disabled for this thread. */ 111 int bps_disabled; 112 int wps_disabled; 113 /* Hardware breakpoints pinned to this task. */ 114 struct perf_event *hbp_break[ARM_MAX_BRP]; 115 struct perf_event *hbp_watch[ARM_MAX_WRP]; 116 #endif 117 }; 118 119 enum vec_type { 120 ARM64_VEC_SVE = 0, 121 ARM64_VEC_SME, 122 ARM64_VEC_MAX, 123 }; 124 125 enum fp_type { 126 FP_STATE_CURRENT, /* Save based on current task state. */ 127 FP_STATE_FPSIMD, 128 FP_STATE_SVE, 129 }; 130 131 struct cpu_context { 132 unsigned long x19; 133 unsigned long x20; 134 unsigned long x21; 135 unsigned long x22; 136 unsigned long x23; 137 unsigned long x24; 138 unsigned long x25; 139 unsigned long x26; 140 unsigned long x27; 141 unsigned long x28; 142 unsigned long fp; 143 unsigned long sp; 144 unsigned long pc; 145 }; 146 147 struct thread_struct { 148 struct cpu_context cpu_context; /* cpu context */ 149 150 /* 151 * Whitelisted fields for hardened usercopy: 152 * Maintainers must ensure manually that this contains no 153 * implicit padding. 154 */ 155 struct { 156 unsigned long tp_value; /* TLS register */ 157 unsigned long tp2_value; 158 struct user_fpsimd_state fpsimd_state; 159 } uw; 160 161 enum fp_type fp_type; /* registers FPSIMD or SVE? */ 162 unsigned int fpsimd_cpu; 163 void *sve_state; /* SVE registers, if any */ 164 void *sme_state; /* ZA and ZT state, if any */ 165 unsigned int vl[ARM64_VEC_MAX]; /* vector length */ 166 unsigned int vl_onexec[ARM64_VEC_MAX]; /* vl after next exec */ 167 unsigned long fault_address; /* fault info */ 168 unsigned long fault_code; /* ESR_EL1 value */ 169 struct debug_info debug; /* debugging */ 170 #ifdef CONFIG_ARM64_PTR_AUTH 171 struct ptrauth_keys_user keys_user; 172 #ifdef CONFIG_ARM64_PTR_AUTH_KERNEL 173 struct ptrauth_keys_kernel keys_kernel; 174 #endif 175 #endif 176 #ifdef CONFIG_ARM64_MTE 177 u64 mte_ctrl; 178 #endif 179 u64 sctlr_user; 180 u64 svcr; 181 u64 tpidr2_el0; 182 }; 183 184 static inline unsigned int thread_get_vl(struct thread_struct *thread, 185 enum vec_type type) 186 { 187 return thread->vl[type]; 188 } 189 190 static inline unsigned int thread_get_sve_vl(struct thread_struct *thread) 191 { 192 return thread_get_vl(thread, ARM64_VEC_SVE); 193 } 194 195 static inline unsigned int thread_get_sme_vl(struct thread_struct *thread) 196 { 197 return thread_get_vl(thread, ARM64_VEC_SME); 198 } 199 200 static inline unsigned int thread_get_cur_vl(struct thread_struct *thread) 201 { 202 if (system_supports_sme() && (thread->svcr & SVCR_SM_MASK)) 203 return thread_get_sme_vl(thread); 204 else 205 return thread_get_sve_vl(thread); 206 } 207 208 unsigned int task_get_vl(const struct task_struct *task, enum vec_type type); 209 void task_set_vl(struct task_struct *task, enum vec_type type, 210 unsigned long vl); 211 void task_set_vl_onexec(struct task_struct *task, enum vec_type type, 212 unsigned long vl); 213 unsigned int task_get_vl_onexec(const struct task_struct *task, 214 enum vec_type type); 215 216 static inline unsigned int task_get_sve_vl(const struct task_struct *task) 217 { 218 return task_get_vl(task, ARM64_VEC_SVE); 219 } 220 221 static inline unsigned int task_get_sme_vl(const struct task_struct *task) 222 { 223 return task_get_vl(task, ARM64_VEC_SME); 224 } 225 226 static inline void task_set_sve_vl(struct task_struct *task, unsigned long vl) 227 { 228 task_set_vl(task, ARM64_VEC_SVE, vl); 229 } 230 231 static inline unsigned int task_get_sve_vl_onexec(const struct task_struct *task) 232 { 233 return task_get_vl_onexec(task, ARM64_VEC_SVE); 234 } 235 236 static inline void task_set_sve_vl_onexec(struct task_struct *task, 237 unsigned long vl) 238 { 239 task_set_vl_onexec(task, ARM64_VEC_SVE, vl); 240 } 241 242 #define SCTLR_USER_MASK \ 243 (SCTLR_ELx_ENIA | SCTLR_ELx_ENIB | SCTLR_ELx_ENDA | SCTLR_ELx_ENDB | \ 244 SCTLR_EL1_TCF0_MASK) 245 246 static inline void arch_thread_struct_whitelist(unsigned long *offset, 247 unsigned long *size) 248 { 249 /* Verify that there is no padding among the whitelisted fields: */ 250 BUILD_BUG_ON(sizeof_field(struct thread_struct, uw) != 251 sizeof_field(struct thread_struct, uw.tp_value) + 252 sizeof_field(struct thread_struct, uw.tp2_value) + 253 sizeof_field(struct thread_struct, uw.fpsimd_state)); 254 255 *offset = offsetof(struct thread_struct, uw); 256 *size = sizeof_field(struct thread_struct, uw); 257 } 258 259 #ifdef CONFIG_COMPAT 260 #define task_user_tls(t) \ 261 ({ \ 262 unsigned long *__tls; \ 263 if (is_compat_thread(task_thread_info(t))) \ 264 __tls = &(t)->thread.uw.tp2_value; \ 265 else \ 266 __tls = &(t)->thread.uw.tp_value; \ 267 __tls; \ 268 }) 269 #else 270 #define task_user_tls(t) (&(t)->thread.uw.tp_value) 271 #endif 272 273 /* Sync TPIDR_EL0 back to thread_struct for current */ 274 void tls_preserve_current_state(void); 275 276 #define INIT_THREAD { \ 277 .fpsimd_cpu = NR_CPUS, \ 278 } 279 280 static inline void start_thread_common(struct pt_regs *regs, unsigned long pc) 281 { 282 s32 previous_syscall = regs->syscallno; 283 memset(regs, 0, sizeof(*regs)); 284 regs->syscallno = previous_syscall; 285 regs->pc = pc; 286 287 if (system_uses_irq_prio_masking()) 288 regs->pmr_save = GIC_PRIO_IRQON; 289 } 290 291 static inline void start_thread(struct pt_regs *regs, unsigned long pc, 292 unsigned long sp) 293 { 294 start_thread_common(regs, pc); 295 regs->pstate = PSR_MODE_EL0t; 296 spectre_v4_enable_task_mitigation(current); 297 regs->sp = sp; 298 } 299 300 #ifdef CONFIG_COMPAT 301 static inline void compat_start_thread(struct pt_regs *regs, unsigned long pc, 302 unsigned long sp) 303 { 304 start_thread_common(regs, pc); 305 regs->pstate = PSR_AA32_MODE_USR; 306 if (pc & 1) 307 regs->pstate |= PSR_AA32_T_BIT; 308 309 #ifdef __AARCH64EB__ 310 regs->pstate |= PSR_AA32_E_BIT; 311 #endif 312 313 spectre_v4_enable_task_mitigation(current); 314 regs->compat_sp = sp; 315 } 316 #endif 317 318 static __always_inline bool is_ttbr0_addr(unsigned long addr) 319 { 320 /* entry assembly clears tags for TTBR0 addrs */ 321 return addr < TASK_SIZE; 322 } 323 324 static __always_inline bool is_ttbr1_addr(unsigned long addr) 325 { 326 /* TTBR1 addresses may have a tag if KASAN_SW_TAGS is in use */ 327 return arch_kasan_reset_tag(addr) >= PAGE_OFFSET; 328 } 329 330 /* Forward declaration, a strange C thing */ 331 struct task_struct; 332 333 unsigned long __get_wchan(struct task_struct *p); 334 335 void update_sctlr_el1(u64 sctlr); 336 337 /* Thread switching */ 338 extern struct task_struct *cpu_switch_to(struct task_struct *prev, 339 struct task_struct *next); 340 341 #define task_pt_regs(p) \ 342 ((struct pt_regs *)(THREAD_SIZE + task_stack_page(p)) - 1) 343 344 #define KSTK_EIP(tsk) ((unsigned long)task_pt_regs(tsk)->pc) 345 #define KSTK_ESP(tsk) user_stack_pointer(task_pt_regs(tsk)) 346 347 /* 348 * Prefetching support 349 */ 350 #define ARCH_HAS_PREFETCH 351 static inline void prefetch(const void *ptr) 352 { 353 asm volatile("prfm pldl1keep, %a0\n" : : "p" (ptr)); 354 } 355 356 #define ARCH_HAS_PREFETCHW 357 static inline void prefetchw(const void *ptr) 358 { 359 asm volatile("prfm pstl1keep, %a0\n" : : "p" (ptr)); 360 } 361 362 extern unsigned long __ro_after_init signal_minsigstksz; /* sigframe size */ 363 extern void __init minsigstksz_setup(void); 364 365 /* 366 * Not at the top of the file due to a direct #include cycle between 367 * <asm/fpsimd.h> and <asm/processor.h>. Deferring this #include 368 * ensures that contents of processor.h are visible to fpsimd.h even if 369 * processor.h is included first. 370 * 371 * These prctl helpers are the only things in this file that require 372 * fpsimd.h. The core code expects them to be in this header. 373 */ 374 #include <asm/fpsimd.h> 375 376 /* Userspace interface for PR_S[MV]E_{SET,GET}_VL prctl()s: */ 377 #define SVE_SET_VL(arg) sve_set_current_vl(arg) 378 #define SVE_GET_VL() sve_get_current_vl() 379 #define SME_SET_VL(arg) sme_set_current_vl(arg) 380 #define SME_GET_VL() sme_get_current_vl() 381 382 /* PR_PAC_RESET_KEYS prctl */ 383 #define PAC_RESET_KEYS(tsk, arg) ptrauth_prctl_reset_keys(tsk, arg) 384 385 /* PR_PAC_{SET,GET}_ENABLED_KEYS prctl */ 386 #define PAC_SET_ENABLED_KEYS(tsk, keys, enabled) \ 387 ptrauth_set_enabled_keys(tsk, keys, enabled) 388 #define PAC_GET_ENABLED_KEYS(tsk) ptrauth_get_enabled_keys(tsk) 389 390 #ifdef CONFIG_ARM64_TAGGED_ADDR_ABI 391 /* PR_{SET,GET}_TAGGED_ADDR_CTRL prctl */ 392 long set_tagged_addr_ctrl(struct task_struct *task, unsigned long arg); 393 long get_tagged_addr_ctrl(struct task_struct *task); 394 #define SET_TAGGED_ADDR_CTRL(arg) set_tagged_addr_ctrl(current, arg) 395 #define GET_TAGGED_ADDR_CTRL() get_tagged_addr_ctrl(current) 396 #endif 397 398 #endif /* __ASSEMBLY__ */ 399 #endif /* __ASM_PROCESSOR_H */ 400