1 /* SPDX-License-Identifier: GPL-2.0 */ 2 /* thread_info.h: MIPS low-level thread information 3 * 4 * Copyright (C) 2002 David Howells (dhowells@redhat.com) 5 * - Incorporating suggestions made by Linus Torvalds and Dave Miller 6 */ 7 8 #ifndef _ASM_THREAD_INFO_H 9 #define _ASM_THREAD_INFO_H 10 11 #ifdef __KERNEL__ 12 13 14 #ifndef __ASSEMBLY__ 15 16 #include <asm/processor.h> 17 18 /* 19 * low level task data that entry.S needs immediate access to 20 * - this struct should fit entirely inside of one cache line 21 * - this struct shares the supervisor stack pages 22 * - if the contents of this structure are changed, the assembly constants 23 * must also be changed 24 */ 25 struct thread_info { 26 struct task_struct *task; /* main task structure */ 27 unsigned long flags; /* low level flags */ 28 unsigned long tp_value; /* thread pointer */ 29 __u32 cpu; /* current CPU */ 30 int preempt_count; /* 0 => preemptable, <0 => BUG */ 31 mm_segment_t addr_limit; /* 32 * thread address space limit: 33 * 0x7fffffff for user-thead 34 * 0xffffffff for kernel-thread 35 */ 36 struct pt_regs *regs; 37 long syscall; /* syscall number */ 38 }; 39 40 /* 41 * macros/functions for gaining access to the thread information structure 42 */ 43 #define INIT_THREAD_INFO(tsk) \ 44 { \ 45 .task = &tsk, \ 46 .flags = _TIF_FIXADE, \ 47 .cpu = 0, \ 48 .preempt_count = INIT_PREEMPT_COUNT, \ 49 .addr_limit = KERNEL_DS, \ 50 } 51 52 /* 53 * A pointer to the struct thread_info for the currently executing thread is 54 * held in register $28/$gp. 55 * 56 * We declare __current_thread_info as a global register variable rather than a 57 * local register variable within current_thread_info() because clang doesn't 58 * support explicit local register variables. 59 * 60 * When building the VDSO we take care not to declare the global register 61 * variable because this causes GCC to not preserve the value of $28/$gp in 62 * functions that change its value (which is common in the PIC VDSO when 63 * accessing the GOT). Since the VDSO shouldn't be accessing 64 * __current_thread_info anyway we declare it extern in order to cause a link 65 * failure if it's referenced. 66 */ 67 #ifdef __VDSO__ 68 extern struct thread_info *__current_thread_info; 69 #else 70 register struct thread_info *__current_thread_info __asm__("$28"); 71 #endif 72 73 static inline struct thread_info *current_thread_info(void) 74 { 75 return __current_thread_info; 76 } 77 78 #endif /* !__ASSEMBLY__ */ 79 80 /* thread information allocation */ 81 #if defined(CONFIG_PAGE_SIZE_4KB) && defined(CONFIG_32BIT) 82 #define THREAD_SIZE_ORDER (1) 83 #endif 84 #if defined(CONFIG_PAGE_SIZE_4KB) && defined(CONFIG_64BIT) 85 #define THREAD_SIZE_ORDER (2) 86 #endif 87 #ifdef CONFIG_PAGE_SIZE_8KB 88 #define THREAD_SIZE_ORDER (1) 89 #endif 90 #ifdef CONFIG_PAGE_SIZE_16KB 91 #define THREAD_SIZE_ORDER (0) 92 #endif 93 #ifdef CONFIG_PAGE_SIZE_32KB 94 #define THREAD_SIZE_ORDER (0) 95 #endif 96 #ifdef CONFIG_PAGE_SIZE_64KB 97 #define THREAD_SIZE_ORDER (0) 98 #endif 99 100 #define THREAD_SIZE (PAGE_SIZE << THREAD_SIZE_ORDER) 101 #define THREAD_MASK (THREAD_SIZE - 1UL) 102 103 #define STACK_WARN (THREAD_SIZE / 8) 104 105 /* 106 * thread information flags 107 * - these are process state flags that various assembly files may need to 108 * access 109 * - pending work-to-be-done flags are in LSW 110 * - other flags in MSW 111 */ 112 #define TIF_SIGPENDING 1 /* signal pending */ 113 #define TIF_NEED_RESCHED 2 /* rescheduling necessary */ 114 #define TIF_SYSCALL_AUDIT 3 /* syscall auditing active */ 115 #define TIF_SECCOMP 4 /* secure computing */ 116 #define TIF_NOTIFY_RESUME 5 /* callback before returning to user */ 117 #define TIF_UPROBE 6 /* breakpointed or singlestepping */ 118 #define TIF_NOTIFY_SIGNAL 7 /* signal notifications exist */ 119 #define TIF_RESTORE_SIGMASK 9 /* restore signal mask in do_signal() */ 120 #define TIF_USEDFPU 16 /* FPU was used by this task this quantum (SMP) */ 121 #define TIF_MEMDIE 18 /* is terminating due to OOM killer */ 122 #define TIF_NOHZ 19 /* in adaptive nohz mode */ 123 #define TIF_FIXADE 20 /* Fix address errors in software */ 124 #define TIF_LOGADE 21 /* Log address errors to syslog */ 125 #define TIF_32BIT_REGS 22 /* 32-bit general purpose registers */ 126 #define TIF_32BIT_ADDR 23 /* 32-bit address space (o32/n32) */ 127 #define TIF_FPUBOUND 24 /* thread bound to FPU-full CPU set */ 128 #define TIF_LOAD_WATCH 25 /* If set, load watch registers */ 129 #define TIF_SYSCALL_TRACEPOINT 26 /* syscall tracepoint instrumentation */ 130 #define TIF_32BIT_FPREGS 27 /* 32-bit floating point registers */ 131 #define TIF_HYBRID_FPREGS 28 /* 64b FP registers, odd singles in bits 63:32 of even doubles */ 132 #define TIF_USEDMSA 29 /* MSA has been used this quantum */ 133 #define TIF_MSA_CTX_LIVE 30 /* MSA context must be preserved */ 134 #define TIF_SYSCALL_TRACE 31 /* syscall trace active */ 135 136 #define _TIF_SYSCALL_TRACE (1<<TIF_SYSCALL_TRACE) 137 #define _TIF_SIGPENDING (1<<TIF_SIGPENDING) 138 #define _TIF_NEED_RESCHED (1<<TIF_NEED_RESCHED) 139 #define _TIF_SYSCALL_AUDIT (1<<TIF_SYSCALL_AUDIT) 140 #define _TIF_SECCOMP (1<<TIF_SECCOMP) 141 #define _TIF_NOTIFY_RESUME (1<<TIF_NOTIFY_RESUME) 142 #define _TIF_UPROBE (1<<TIF_UPROBE) 143 #define _TIF_NOTIFY_SIGNAL (1<<TIF_NOTIFY_SIGNAL) 144 #define _TIF_USEDFPU (1<<TIF_USEDFPU) 145 #define _TIF_NOHZ (1<<TIF_NOHZ) 146 #define _TIF_FIXADE (1<<TIF_FIXADE) 147 #define _TIF_LOGADE (1<<TIF_LOGADE) 148 #define _TIF_32BIT_REGS (1<<TIF_32BIT_REGS) 149 #define _TIF_32BIT_ADDR (1<<TIF_32BIT_ADDR) 150 #define _TIF_FPUBOUND (1<<TIF_FPUBOUND) 151 #define _TIF_LOAD_WATCH (1<<TIF_LOAD_WATCH) 152 #define _TIF_32BIT_FPREGS (1<<TIF_32BIT_FPREGS) 153 #define _TIF_HYBRID_FPREGS (1<<TIF_HYBRID_FPREGS) 154 #define _TIF_USEDMSA (1<<TIF_USEDMSA) 155 #define _TIF_MSA_CTX_LIVE (1<<TIF_MSA_CTX_LIVE) 156 #define _TIF_SYSCALL_TRACEPOINT (1<<TIF_SYSCALL_TRACEPOINT) 157 158 #define _TIF_WORK_SYSCALL_ENTRY (_TIF_NOHZ | _TIF_SYSCALL_TRACE | \ 159 _TIF_SYSCALL_AUDIT | \ 160 _TIF_SYSCALL_TRACEPOINT | _TIF_SECCOMP) 161 162 /* work to do in syscall_trace_leave() */ 163 #define _TIF_WORK_SYSCALL_EXIT (_TIF_NOHZ | _TIF_SYSCALL_TRACE | \ 164 _TIF_SYSCALL_AUDIT | _TIF_SYSCALL_TRACEPOINT) 165 166 /* work to do on interrupt/exception return */ 167 #define _TIF_WORK_MASK \ 168 (_TIF_SIGPENDING | _TIF_NEED_RESCHED | _TIF_NOTIFY_RESUME | \ 169 _TIF_UPROBE | _TIF_NOTIFY_SIGNAL) 170 /* work to do on any return to u-space */ 171 #define _TIF_ALLWORK_MASK (_TIF_NOHZ | _TIF_WORK_MASK | \ 172 _TIF_WORK_SYSCALL_EXIT | \ 173 _TIF_SYSCALL_TRACEPOINT) 174 175 /* 176 * We stash processor id into a COP0 register to retrieve it fast 177 * at kernel exception entry. 178 */ 179 #if defined(CONFIG_MIPS_PGD_C0_CONTEXT) 180 #define SMP_CPUID_REG 20, 0 /* XCONTEXT */ 181 #define ASM_SMP_CPUID_REG $20 182 #define SMP_CPUID_PTRSHIFT 48 183 #else 184 #define SMP_CPUID_REG 4, 0 /* CONTEXT */ 185 #define ASM_SMP_CPUID_REG $4 186 #define SMP_CPUID_PTRSHIFT 23 187 #endif 188 189 #ifdef CONFIG_64BIT 190 #define SMP_CPUID_REGSHIFT (SMP_CPUID_PTRSHIFT + 3) 191 #else 192 #define SMP_CPUID_REGSHIFT (SMP_CPUID_PTRSHIFT + 2) 193 #endif 194 195 #define ASM_CPUID_MFC0 MFC0 196 #define UASM_i_CPUID_MFC0 UASM_i_MFC0 197 198 #endif /* __KERNEL__ */ 199 #endif /* _ASM_THREAD_INFO_H */ 200