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 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__ 68extern struct thread_info *__current_thread_info; 69#else 70register struct thread_info *__current_thread_info __asm__("$28"); 71#endif 72 73static 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