1/* thread_info.h: Meta low-level thread information 2 * 3 * Copyright (C) 2002 David Howells (dhowells@redhat.com) 4 * - Incorporating suggestions made by Linus Torvalds and Dave Miller 5 * 6 * Meta port by Imagination Technologies 7 */ 8 9#ifndef _ASM_THREAD_INFO_H 10#define _ASM_THREAD_INFO_H 11 12#include <linux/compiler.h> 13#include <asm/page.h> 14 15#ifndef __ASSEMBLY__ 16#include <asm/processor.h> 17#endif 18 19/* 20 * low level task data that entry.S needs immediate access to 21 * - this struct should fit entirely inside of one cache line 22 * - this struct shares the supervisor stack pages 23 * - if the contents of this structure are changed, the assembly constants must 24 * also be changed 25 */ 26#ifndef __ASSEMBLY__ 27 28/* This must be 8 byte aligned so we can ensure stack alignment. */ 29struct thread_info { 30 struct task_struct *task; /* main task structure */ 31 struct exec_domain *exec_domain; /* execution domain */ 32 unsigned long flags; /* low level flags */ 33 unsigned long status; /* thread-synchronous flags */ 34 u32 cpu; /* current CPU */ 35 int preempt_count; /* 0 => preemptable, <0 => BUG */ 36 37 mm_segment_t addr_limit; /* thread address space */ 38 struct restart_block restart_block; 39 40 u8 supervisor_stack[0]; 41}; 42 43#else /* !__ASSEMBLY__ */ 44 45#include <generated/asm-offsets.h> 46 47#endif 48 49#ifdef CONFIG_4KSTACKS 50#define THREAD_SHIFT 12 51#else 52#define THREAD_SHIFT 13 53#endif 54 55#if THREAD_SHIFT >= PAGE_SHIFT 56#define THREAD_SIZE_ORDER (THREAD_SHIFT - PAGE_SHIFT) 57#else 58#define THREAD_SIZE_ORDER 0 59#endif 60 61#define THREAD_SIZE (PAGE_SIZE << THREAD_SIZE_ORDER) 62 63#define STACK_WARN (THREAD_SIZE/8) 64/* 65 * macros/functions for gaining access to the thread information structure 66 */ 67#ifndef __ASSEMBLY__ 68 69#define INIT_THREAD_INFO(tsk) \ 70{ \ 71 .task = &tsk, \ 72 .exec_domain = &default_exec_domain, \ 73 .flags = 0, \ 74 .cpu = 0, \ 75 .preempt_count = INIT_PREEMPT_COUNT, \ 76 .addr_limit = KERNEL_DS, \ 77 .restart_block = { \ 78 .fn = do_no_restart_syscall, \ 79 }, \ 80} 81 82#define init_thread_info (init_thread_union.thread_info) 83#define init_stack (init_thread_union.stack) 84 85/* how to get the current stack pointer from C */ 86register unsigned long current_stack_pointer asm("A0StP") __used; 87 88/* how to get the thread information struct from C */ 89static inline struct thread_info *current_thread_info(void) 90{ 91 return (struct thread_info *)(current_stack_pointer & 92 ~(THREAD_SIZE - 1)); 93} 94 95#define __HAVE_ARCH_KSTACK_END 96static inline int kstack_end(void *addr) 97{ 98 return addr == (void *) (((unsigned long) addr & ~(THREAD_SIZE - 1)) 99 + sizeof(struct thread_info)); 100} 101 102#endif 103 104/* 105 * thread information flags 106 * - these are process state flags that various assembly files may need to 107 * access 108 * - pending work-to-be-done flags are in LSW 109 * - other flags in MSW 110 */ 111#define TIF_SYSCALL_TRACE 0 /* syscall trace active */ 112#define TIF_SIGPENDING 1 /* signal pending */ 113#define TIF_NEED_RESCHED 2 /* rescheduling necessary */ 114#define TIF_SINGLESTEP 3 /* restore singlestep on return to user 115 mode */ 116#define TIF_SYSCALL_AUDIT 4 /* syscall auditing active */ 117#define TIF_SECCOMP 5 /* secure computing */ 118#define TIF_RESTORE_SIGMASK 6 /* restore signal mask in do_signal() */ 119#define TIF_NOTIFY_RESUME 7 /* callback before returning to user */ 120#define TIF_POLLING_NRFLAG 8 /* true if poll_idle() is polling 121 TIF_NEED_RESCHED */ 122#define TIF_MEMDIE 9 /* is terminating due to OOM killer */ 123#define TIF_SYSCALL_TRACEPOINT 10 /* syscall tracepoint instrumentation */ 124 125 126#define _TIF_SYSCALL_TRACE (1<<TIF_SYSCALL_TRACE) 127#define _TIF_SIGPENDING (1<<TIF_SIGPENDING) 128#define _TIF_NEED_RESCHED (1<<TIF_NEED_RESCHED) 129#define _TIF_SINGLESTEP (1<<TIF_SINGLESTEP) 130#define _TIF_SYSCALL_AUDIT (1<<TIF_SYSCALL_AUDIT) 131#define _TIF_SECCOMP (1<<TIF_SECCOMP) 132#define _TIF_NOTIFY_RESUME (1<<TIF_NOTIFY_RESUME) 133#define _TIF_RESTORE_SIGMASK (1<<TIF_RESTORE_SIGMASK) 134#define _TIF_SYSCALL_TRACEPOINT (1<<TIF_SYSCALL_TRACEPOINT) 135 136/* work to do in syscall trace */ 137#define _TIF_WORK_SYSCALL_MASK (_TIF_SYSCALL_TRACE | _TIF_SINGLESTEP | \ 138 _TIF_SYSCALL_AUDIT | _TIF_SECCOMP | \ 139 _TIF_SYSCALL_TRACEPOINT) 140 141/* work to do on any return to u-space */ 142#define _TIF_ALLWORK_MASK (_TIF_SYSCALL_TRACE | _TIF_SIGPENDING | \ 143 _TIF_NEED_RESCHED | _TIF_SYSCALL_AUDIT | \ 144 _TIF_SINGLESTEP | _TIF_RESTORE_SIGMASK | \ 145 _TIF_NOTIFY_RESUME) 146 147/* work to do on interrupt/exception return */ 148#define _TIF_WORK_MASK (_TIF_ALLWORK_MASK & ~(_TIF_SYSCALL_TRACE | \ 149 _TIF_SYSCALL_AUDIT | _TIF_SINGLESTEP)) 150 151#endif /* _ASM_THREAD_INFO_H */ 152