1 /* thread_info.h: 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 7 #ifndef _ASM_X86_THREAD_INFO_H 8 #define _ASM_X86_THREAD_INFO_H 9 10 #include <linux/compiler.h> 11 #include <asm/page.h> 12 #include <asm/percpu.h> 13 #include <asm/types.h> 14 15 /* 16 * low level task data that entry.S needs immediate access to 17 * - this struct should fit entirely inside of one cache line 18 * - this struct shares the supervisor stack pages 19 */ 20 #ifndef __ASSEMBLY__ 21 struct task_struct; 22 struct exec_domain; 23 #include <asm/processor.h> 24 #include <linux/atomic.h> 25 26 struct thread_info { 27 struct task_struct *task; /* main task structure */ 28 struct exec_domain *exec_domain; /* execution domain */ 29 __u32 flags; /* low level flags */ 30 __u32 status; /* thread synchronous flags */ 31 __u32 cpu; /* current CPU */ 32 int saved_preempt_count; 33 mm_segment_t addr_limit; 34 struct restart_block restart_block; 35 void __user *sysenter_return; 36 unsigned int sig_on_uaccess_error:1; 37 unsigned int uaccess_err:1; /* uaccess failed */ 38 }; 39 40 #define INIT_THREAD_INFO(tsk) \ 41 { \ 42 .task = &tsk, \ 43 .exec_domain = &default_exec_domain, \ 44 .flags = 0, \ 45 .cpu = 0, \ 46 .saved_preempt_count = INIT_PREEMPT_COUNT, \ 47 .addr_limit = KERNEL_DS, \ 48 .restart_block = { \ 49 .fn = do_no_restart_syscall, \ 50 }, \ 51 } 52 53 #define init_thread_info (init_thread_union.thread_info) 54 #define init_stack (init_thread_union.stack) 55 56 #else /* !__ASSEMBLY__ */ 57 58 #include <asm/asm-offsets.h> 59 60 #endif 61 62 /* 63 * thread information flags 64 * - these are process state flags that various assembly files 65 * may need to access 66 * - pending work-to-be-done flags are in LSW 67 * - other flags in MSW 68 * Warning: layout of LSW is hardcoded in entry.S 69 */ 70 #define TIF_SYSCALL_TRACE 0 /* syscall trace active */ 71 #define TIF_NOTIFY_RESUME 1 /* callback before returning to user */ 72 #define TIF_SIGPENDING 2 /* signal pending */ 73 #define TIF_NEED_RESCHED 3 /* rescheduling necessary */ 74 #define TIF_SINGLESTEP 4 /* reenable singlestep on user return*/ 75 #define TIF_SYSCALL_EMU 6 /* syscall emulation active */ 76 #define TIF_SYSCALL_AUDIT 7 /* syscall auditing active */ 77 #define TIF_SECCOMP 8 /* secure computing */ 78 #define TIF_MCE_NOTIFY 10 /* notify userspace of an MCE */ 79 #define TIF_USER_RETURN_NOTIFY 11 /* notify kernel of userspace return */ 80 #define TIF_UPROBE 12 /* breakpointed or singlestepping */ 81 #define TIF_NOTSC 16 /* TSC is not accessible in userland */ 82 #define TIF_IA32 17 /* IA32 compatibility process */ 83 #define TIF_FORK 18 /* ret_from_fork */ 84 #define TIF_NOHZ 19 /* in adaptive nohz mode */ 85 #define TIF_MEMDIE 20 /* is terminating due to OOM killer */ 86 #define TIF_IO_BITMAP 22 /* uses I/O bitmap */ 87 #define TIF_FORCED_TF 24 /* true if TF in eflags artificially */ 88 #define TIF_BLOCKSTEP 25 /* set when we want DEBUGCTLMSR_BTF */ 89 #define TIF_LAZY_MMU_UPDATES 27 /* task is updating the mmu lazily */ 90 #define TIF_SYSCALL_TRACEPOINT 28 /* syscall tracepoint instrumentation */ 91 #define TIF_ADDR32 29 /* 32-bit address space on 64 bits */ 92 #define TIF_X32 30 /* 32-bit native x86-64 binary */ 93 94 #define _TIF_SYSCALL_TRACE (1 << TIF_SYSCALL_TRACE) 95 #define _TIF_NOTIFY_RESUME (1 << TIF_NOTIFY_RESUME) 96 #define _TIF_SIGPENDING (1 << TIF_SIGPENDING) 97 #define _TIF_SINGLESTEP (1 << TIF_SINGLESTEP) 98 #define _TIF_NEED_RESCHED (1 << TIF_NEED_RESCHED) 99 #define _TIF_SYSCALL_EMU (1 << TIF_SYSCALL_EMU) 100 #define _TIF_SYSCALL_AUDIT (1 << TIF_SYSCALL_AUDIT) 101 #define _TIF_SECCOMP (1 << TIF_SECCOMP) 102 #define _TIF_MCE_NOTIFY (1 << TIF_MCE_NOTIFY) 103 #define _TIF_USER_RETURN_NOTIFY (1 << TIF_USER_RETURN_NOTIFY) 104 #define _TIF_UPROBE (1 << TIF_UPROBE) 105 #define _TIF_NOTSC (1 << TIF_NOTSC) 106 #define _TIF_IA32 (1 << TIF_IA32) 107 #define _TIF_FORK (1 << TIF_FORK) 108 #define _TIF_NOHZ (1 << TIF_NOHZ) 109 #define _TIF_IO_BITMAP (1 << TIF_IO_BITMAP) 110 #define _TIF_FORCED_TF (1 << TIF_FORCED_TF) 111 #define _TIF_BLOCKSTEP (1 << TIF_BLOCKSTEP) 112 #define _TIF_LAZY_MMU_UPDATES (1 << TIF_LAZY_MMU_UPDATES) 113 #define _TIF_SYSCALL_TRACEPOINT (1 << TIF_SYSCALL_TRACEPOINT) 114 #define _TIF_ADDR32 (1 << TIF_ADDR32) 115 #define _TIF_X32 (1 << TIF_X32) 116 117 /* work to do in syscall_trace_enter() */ 118 #define _TIF_WORK_SYSCALL_ENTRY \ 119 (_TIF_SYSCALL_TRACE | _TIF_SYSCALL_EMU | _TIF_SYSCALL_AUDIT | \ 120 _TIF_SECCOMP | _TIF_SINGLESTEP | _TIF_SYSCALL_TRACEPOINT | \ 121 _TIF_NOHZ) 122 123 /* work to do in syscall_trace_leave() */ 124 #define _TIF_WORK_SYSCALL_EXIT \ 125 (_TIF_SYSCALL_TRACE | _TIF_SYSCALL_AUDIT | _TIF_SINGLESTEP | \ 126 _TIF_SYSCALL_TRACEPOINT | _TIF_NOHZ) 127 128 /* work to do on interrupt/exception return */ 129 #define _TIF_WORK_MASK \ 130 (0x0000FFFF & \ 131 ~(_TIF_SYSCALL_TRACE|_TIF_SYSCALL_AUDIT| \ 132 _TIF_SINGLESTEP|_TIF_SECCOMP|_TIF_SYSCALL_EMU)) 133 134 /* work to do on any return to user space */ 135 #define _TIF_ALLWORK_MASK \ 136 ((0x0000FFFF & ~_TIF_SECCOMP) | _TIF_SYSCALL_TRACEPOINT | \ 137 _TIF_NOHZ) 138 139 /* Only used for 64 bit */ 140 #define _TIF_DO_NOTIFY_MASK \ 141 (_TIF_SIGPENDING | _TIF_MCE_NOTIFY | _TIF_NOTIFY_RESUME | \ 142 _TIF_USER_RETURN_NOTIFY) 143 144 /* flags to check in __switch_to() */ 145 #define _TIF_WORK_CTXSW \ 146 (_TIF_IO_BITMAP|_TIF_NOTSC|_TIF_BLOCKSTEP) 147 148 #define _TIF_WORK_CTXSW_PREV (_TIF_WORK_CTXSW|_TIF_USER_RETURN_NOTIFY) 149 #define _TIF_WORK_CTXSW_NEXT (_TIF_WORK_CTXSW) 150 151 #define STACK_WARN (THREAD_SIZE/8) 152 #define KERNEL_STACK_OFFSET (5*(BITS_PER_LONG/8)) 153 154 /* 155 * macros/functions for gaining access to the thread information structure 156 * 157 * preempt_count needs to be 1 initially, until the scheduler is functional. 158 */ 159 #ifndef __ASSEMBLY__ 160 161 DECLARE_PER_CPU(unsigned long, kernel_stack); 162 163 static inline struct thread_info *current_thread_info(void) 164 { 165 struct thread_info *ti; 166 ti = (void *)(this_cpu_read_stable(kernel_stack) + 167 KERNEL_STACK_OFFSET - THREAD_SIZE); 168 return ti; 169 } 170 171 #else /* !__ASSEMBLY__ */ 172 173 /* how to get the thread information struct from ASM */ 174 #define GET_THREAD_INFO(reg) \ 175 _ASM_MOV PER_CPU_VAR(kernel_stack),reg ; \ 176 _ASM_SUB $(THREAD_SIZE-KERNEL_STACK_OFFSET),reg ; 177 178 /* 179 * Same if PER_CPU_VAR(kernel_stack) is, perhaps with some offset, already in 180 * a certain register (to be used in assembler memory operands). 181 */ 182 #define THREAD_INFO(reg, off) KERNEL_STACK_OFFSET+(off)-THREAD_SIZE(reg) 183 184 #endif 185 186 /* 187 * Thread-synchronous status. 188 * 189 * This is different from the flags in that nobody else 190 * ever touches our thread-synchronous status, so we don't 191 * have to worry about atomic accesses. 192 */ 193 #define TS_COMPAT 0x0002 /* 32bit syscall active (64BIT)*/ 194 #define TS_POLLING 0x0004 /* idle task polling need_resched, 195 skip sending interrupt */ 196 #define TS_RESTORE_SIGMASK 0x0008 /* restore signal mask in do_signal() */ 197 198 #ifndef __ASSEMBLY__ 199 #define HAVE_SET_RESTORE_SIGMASK 1 200 static inline void set_restore_sigmask(void) 201 { 202 struct thread_info *ti = current_thread_info(); 203 ti->status |= TS_RESTORE_SIGMASK; 204 WARN_ON(!test_bit(TIF_SIGPENDING, (unsigned long *)&ti->flags)); 205 } 206 static inline void clear_restore_sigmask(void) 207 { 208 current_thread_info()->status &= ~TS_RESTORE_SIGMASK; 209 } 210 static inline bool test_restore_sigmask(void) 211 { 212 return current_thread_info()->status & TS_RESTORE_SIGMASK; 213 } 214 static inline bool test_and_clear_restore_sigmask(void) 215 { 216 struct thread_info *ti = current_thread_info(); 217 if (!(ti->status & TS_RESTORE_SIGMASK)) 218 return false; 219 ti->status &= ~TS_RESTORE_SIGMASK; 220 return true; 221 } 222 223 static inline bool is_ia32_task(void) 224 { 225 #ifdef CONFIG_X86_32 226 return true; 227 #endif 228 #ifdef CONFIG_IA32_EMULATION 229 if (current_thread_info()->status & TS_COMPAT) 230 return true; 231 #endif 232 return false; 233 } 234 #endif /* !__ASSEMBLY__ */ 235 236 #ifndef __ASSEMBLY__ 237 extern void arch_task_cache_init(void); 238 extern int arch_dup_task_struct(struct task_struct *dst, struct task_struct *src); 239 extern void arch_release_task_struct(struct task_struct *tsk); 240 #endif 241 #endif /* _ASM_X86_THREAD_INFO_H */ 242