1 /* 2 * Based on arch/arm/include/asm/processor.h 3 * 4 * Copyright (C) 1995-1999 Russell King 5 * Copyright (C) 2012 ARM Ltd. 6 * 7 * This program is free software; you can redistribute it and/or modify 8 * it under the terms of the GNU General Public License version 2 as 9 * published by the Free Software Foundation. 10 * 11 * This program is distributed in the hope that it will be useful, 12 * but WITHOUT ANY WARRANTY; without even the implied warranty of 13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 14 * GNU General Public License for more details. 15 * 16 * You should have received a copy of the GNU General Public License 17 * along with this program. If not, see <http://www.gnu.org/licenses/>. 18 */ 19 #ifndef __ASM_PROCESSOR_H 20 #define __ASM_PROCESSOR_H 21 22 #define TASK_SIZE_64 (UL(1) << VA_BITS) 23 24 #define KERNEL_DS UL(-1) 25 #define USER_DS (TASK_SIZE_64 - 1) 26 27 #ifndef __ASSEMBLY__ 28 #ifdef __KERNEL__ 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 36 #include <asm/alternative.h> 37 #include <asm/cpufeature.h> 38 #include <asm/hw_breakpoint.h> 39 #include <asm/lse.h> 40 #include <asm/pgtable-hwdef.h> 41 #include <asm/ptrace.h> 42 #include <asm/types.h> 43 44 /* 45 * TASK_SIZE - the maximum size of a user space task. 46 * TASK_UNMAPPED_BASE - the lower boundary of the mmap VM area. 47 */ 48 #ifdef CONFIG_COMPAT 49 #define TASK_SIZE_32 UL(0x100000000) 50 #define TASK_SIZE (test_thread_flag(TIF_32BIT) ? \ 51 TASK_SIZE_32 : TASK_SIZE_64) 52 #define TASK_SIZE_OF(tsk) (test_tsk_thread_flag(tsk, TIF_32BIT) ? \ 53 TASK_SIZE_32 : TASK_SIZE_64) 54 #else 55 #define TASK_SIZE TASK_SIZE_64 56 #endif /* CONFIG_COMPAT */ 57 58 #define TASK_UNMAPPED_BASE (PAGE_ALIGN(TASK_SIZE / 4)) 59 60 #define STACK_TOP_MAX TASK_SIZE_64 61 #ifdef CONFIG_COMPAT 62 #define AARCH32_VECTORS_BASE 0xffff0000 63 #define STACK_TOP (test_thread_flag(TIF_32BIT) ? \ 64 AARCH32_VECTORS_BASE : STACK_TOP_MAX) 65 #else 66 #define STACK_TOP STACK_TOP_MAX 67 #endif /* CONFIG_COMPAT */ 68 69 extern phys_addr_t arm64_dma_phys_limit; 70 #define ARCH_LOW_ADDRESS_LIMIT (arm64_dma_phys_limit - 1) 71 72 struct debug_info { 73 #ifdef CONFIG_HAVE_HW_BREAKPOINT 74 /* Have we suspended stepping by a debugger? */ 75 int suspended_step; 76 /* Allow breakpoints and watchpoints to be disabled for this thread. */ 77 int bps_disabled; 78 int wps_disabled; 79 /* Hardware breakpoints pinned to this task. */ 80 struct perf_event *hbp_break[ARM_MAX_BRP]; 81 struct perf_event *hbp_watch[ARM_MAX_WRP]; 82 #endif 83 }; 84 85 struct cpu_context { 86 unsigned long x19; 87 unsigned long x20; 88 unsigned long x21; 89 unsigned long x22; 90 unsigned long x23; 91 unsigned long x24; 92 unsigned long x25; 93 unsigned long x26; 94 unsigned long x27; 95 unsigned long x28; 96 unsigned long fp; 97 unsigned long sp; 98 unsigned long pc; 99 }; 100 101 struct thread_struct { 102 struct cpu_context cpu_context; /* cpu context */ 103 104 /* 105 * Whitelisted fields for hardened usercopy: 106 * Maintainers must ensure manually that this contains no 107 * implicit padding. 108 */ 109 struct { 110 unsigned long tp_value; /* TLS register */ 111 unsigned long tp2_value; 112 struct user_fpsimd_state fpsimd_state; 113 } uw; 114 115 unsigned int fpsimd_cpu; 116 void *sve_state; /* SVE registers, if any */ 117 unsigned int sve_vl; /* SVE vector length */ 118 unsigned int sve_vl_onexec; /* SVE vl after next exec */ 119 unsigned long fault_address; /* fault info */ 120 unsigned long fault_code; /* ESR_EL1 value */ 121 struct debug_info debug; /* debugging */ 122 }; 123 124 static inline void arch_thread_struct_whitelist(unsigned long *offset, 125 unsigned long *size) 126 { 127 /* Verify that there is no padding among the whitelisted fields: */ 128 BUILD_BUG_ON(sizeof_field(struct thread_struct, uw) != 129 sizeof_field(struct thread_struct, uw.tp_value) + 130 sizeof_field(struct thread_struct, uw.tp2_value) + 131 sizeof_field(struct thread_struct, uw.fpsimd_state)); 132 133 *offset = offsetof(struct thread_struct, uw); 134 *size = sizeof_field(struct thread_struct, uw); 135 } 136 137 #ifdef CONFIG_COMPAT 138 #define task_user_tls(t) \ 139 ({ \ 140 unsigned long *__tls; \ 141 if (is_compat_thread(task_thread_info(t))) \ 142 __tls = &(t)->thread.uw.tp2_value; \ 143 else \ 144 __tls = &(t)->thread.uw.tp_value; \ 145 __tls; \ 146 }) 147 #else 148 #define task_user_tls(t) (&(t)->thread.uw.tp_value) 149 #endif 150 151 /* Sync TPIDR_EL0 back to thread_struct for current */ 152 void tls_preserve_current_state(void); 153 154 #define INIT_THREAD { \ 155 .fpsimd_cpu = NR_CPUS, \ 156 } 157 158 static inline void start_thread_common(struct pt_regs *regs, unsigned long pc) 159 { 160 memset(regs, 0, sizeof(*regs)); 161 forget_syscall(regs); 162 regs->pc = pc; 163 } 164 165 static inline void start_thread(struct pt_regs *regs, unsigned long pc, 166 unsigned long sp) 167 { 168 start_thread_common(regs, pc); 169 regs->pstate = PSR_MODE_EL0t; 170 171 if (arm64_get_ssbd_state() != ARM64_SSBD_FORCE_ENABLE) 172 regs->pstate |= PSR_SSBS_BIT; 173 174 regs->sp = sp; 175 } 176 177 #ifdef CONFIG_COMPAT 178 static inline void compat_start_thread(struct pt_regs *regs, unsigned long pc, 179 unsigned long sp) 180 { 181 start_thread_common(regs, pc); 182 regs->pstate = PSR_AA32_MODE_USR; 183 if (pc & 1) 184 regs->pstate |= PSR_AA32_T_BIT; 185 186 #ifdef __AARCH64EB__ 187 regs->pstate |= PSR_AA32_E_BIT; 188 #endif 189 190 if (arm64_get_ssbd_state() != ARM64_SSBD_FORCE_ENABLE) 191 regs->pstate |= PSR_AA32_SSBS_BIT; 192 193 regs->compat_sp = sp; 194 } 195 #endif 196 197 /* Forward declaration, a strange C thing */ 198 struct task_struct; 199 200 /* Free all resources held by a thread. */ 201 extern void release_thread(struct task_struct *); 202 203 unsigned long get_wchan(struct task_struct *p); 204 205 static inline void cpu_relax(void) 206 { 207 asm volatile("yield" ::: "memory"); 208 } 209 210 /* Thread switching */ 211 extern struct task_struct *cpu_switch_to(struct task_struct *prev, 212 struct task_struct *next); 213 214 #define task_pt_regs(p) \ 215 ((struct pt_regs *)(THREAD_SIZE + task_stack_page(p)) - 1) 216 217 #define KSTK_EIP(tsk) ((unsigned long)task_pt_regs(tsk)->pc) 218 #define KSTK_ESP(tsk) user_stack_pointer(task_pt_regs(tsk)) 219 220 /* 221 * Prefetching support 222 */ 223 #define ARCH_HAS_PREFETCH 224 static inline void prefetch(const void *ptr) 225 { 226 asm volatile("prfm pldl1keep, %a0\n" : : "p" (ptr)); 227 } 228 229 #define ARCH_HAS_PREFETCHW 230 static inline void prefetchw(const void *ptr) 231 { 232 asm volatile("prfm pstl1keep, %a0\n" : : "p" (ptr)); 233 } 234 235 #define ARCH_HAS_SPINLOCK_PREFETCH 236 static inline void spin_lock_prefetch(const void *ptr) 237 { 238 asm volatile(ARM64_LSE_ATOMIC_INSN( 239 "prfm pstl1strm, %a0", 240 "nop") : : "p" (ptr)); 241 } 242 243 #define HAVE_ARCH_PICK_MMAP_LAYOUT 244 245 #endif 246 247 extern unsigned long __ro_after_init signal_minsigstksz; /* sigframe size */ 248 extern void __init minsigstksz_setup(void); 249 250 /* 251 * Not at the top of the file due to a direct #include cycle between 252 * <asm/fpsimd.h> and <asm/processor.h>. Deferring this #include 253 * ensures that contents of processor.h are visible to fpsimd.h even if 254 * processor.h is included first. 255 * 256 * These prctl helpers are the only things in this file that require 257 * fpsimd.h. The core code expects them to be in this header. 258 */ 259 #include <asm/fpsimd.h> 260 261 /* Userspace interface for PR_SVE_{SET,GET}_VL prctl()s: */ 262 #define SVE_SET_VL(arg) sve_set_current_vl(arg) 263 #define SVE_GET_VL() sve_get_current_vl() 264 265 /* 266 * For CONFIG_GCC_PLUGIN_STACKLEAK 267 * 268 * These need to be macros because otherwise we get stuck in a nightmare 269 * of header definitions for the use of task_stack_page. 270 */ 271 272 #define current_top_of_stack() \ 273 ({ \ 274 struct stack_info _info; \ 275 BUG_ON(!on_accessible_stack(current, current_stack_pointer, &_info)); \ 276 _info.high; \ 277 }) 278 #define on_thread_stack() (on_task_stack(current, current_stack_pointer, NULL)) 279 280 #endif /* __ASSEMBLY__ */ 281 #endif /* __ASM_PROCESSOR_H */ 282