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