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/types.h> 13 14 /* 15 * low level task data that entry.S needs immediate access to 16 * - this struct should fit entirely inside of one cache line 17 * - this struct shares the supervisor stack pages 18 */ 19 #ifndef __ASSEMBLY__ 20 struct task_struct; 21 struct exec_domain; 22 #include <asm/processor.h> 23 #include <asm/ftrace.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 preempt_count; /* 0 => preemptable, 33 <0 => BUG */ 34 mm_segment_t addr_limit; 35 struct restart_block restart_block; 36 void __user *sysenter_return; 37 #ifdef CONFIG_X86_32 38 unsigned long previous_esp; /* ESP of the previous stack in 39 case of nested (IRQ) stacks 40 */ 41 __u8 supervisor_stack[0]; 42 #endif 43 unsigned int sig_on_uaccess_error:1; 44 unsigned int uaccess_err:1; /* uaccess failed */ 45 }; 46 47 #define INIT_THREAD_INFO(tsk) \ 48 { \ 49 .task = &tsk, \ 50 .exec_domain = &default_exec_domain, \ 51 .flags = 0, \ 52 .cpu = 0, \ 53 .preempt_count = INIT_PREEMPT_COUNT, \ 54 .addr_limit = KERNEL_DS, \ 55 .restart_block = { \ 56 .fn = do_no_restart_syscall, \ 57 }, \ 58 } 59 60 #define init_thread_info (init_thread_union.thread_info) 61 #define init_stack (init_thread_union.stack) 62 63 #else /* !__ASSEMBLY__ */ 64 65 #include <asm/asm-offsets.h> 66 67 #endif 68 69 /* 70 * thread information flags 71 * - these are process state flags that various assembly files 72 * may need to access 73 * - pending work-to-be-done flags are in LSW 74 * - other flags in MSW 75 * Warning: layout of LSW is hardcoded in entry.S 76 */ 77 #define TIF_SYSCALL_TRACE 0 /* syscall trace active */ 78 #define TIF_NOTIFY_RESUME 1 /* callback before returning to user */ 79 #define TIF_SIGPENDING 2 /* signal pending */ 80 #define TIF_NEED_RESCHED 3 /* rescheduling necessary */ 81 #define TIF_SINGLESTEP 4 /* reenable singlestep on user return*/ 82 #define TIF_SYSCALL_EMU 6 /* syscall emulation active */ 83 #define TIF_SYSCALL_AUDIT 7 /* syscall auditing active */ 84 #define TIF_SECCOMP 8 /* secure computing */ 85 #define TIF_MCE_NOTIFY 10 /* notify userspace of an MCE */ 86 #define TIF_USER_RETURN_NOTIFY 11 /* notify kernel of userspace return */ 87 #define TIF_UPROBE 12 /* breakpointed or singlestepping */ 88 #define TIF_NOTSC 16 /* TSC is not accessible in userland */ 89 #define TIF_IA32 17 /* IA32 compatibility process */ 90 #define TIF_FORK 18 /* ret_from_fork */ 91 #define TIF_NOHZ 19 /* in adaptive nohz mode */ 92 #define TIF_MEMDIE 20 /* is terminating due to OOM killer */ 93 #define TIF_DEBUG 21 /* uses debug registers */ 94 #define TIF_IO_BITMAP 22 /* uses I/O bitmap */ 95 #define TIF_FORCED_TF 24 /* true if TF in eflags artificially */ 96 #define TIF_BLOCKSTEP 25 /* set when we want DEBUGCTLMSR_BTF */ 97 #define TIF_LAZY_MMU_UPDATES 27 /* task is updating the mmu lazily */ 98 #define TIF_SYSCALL_TRACEPOINT 28 /* syscall tracepoint instrumentation */ 99 #define TIF_ADDR32 29 /* 32-bit address space on 64 bits */ 100 #define TIF_X32 30 /* 32-bit native x86-64 binary */ 101 102 #define _TIF_SYSCALL_TRACE (1 << TIF_SYSCALL_TRACE) 103 #define _TIF_NOTIFY_RESUME (1 << TIF_NOTIFY_RESUME) 104 #define _TIF_SIGPENDING (1 << TIF_SIGPENDING) 105 #define _TIF_SINGLESTEP (1 << TIF_SINGLESTEP) 106 #define _TIF_NEED_RESCHED (1 << TIF_NEED_RESCHED) 107 #define _TIF_SYSCALL_EMU (1 << TIF_SYSCALL_EMU) 108 #define _TIF_SYSCALL_AUDIT (1 << TIF_SYSCALL_AUDIT) 109 #define _TIF_SECCOMP (1 << TIF_SECCOMP) 110 #define _TIF_MCE_NOTIFY (1 << TIF_MCE_NOTIFY) 111 #define _TIF_USER_RETURN_NOTIFY (1 << TIF_USER_RETURN_NOTIFY) 112 #define _TIF_UPROBE (1 << TIF_UPROBE) 113 #define _TIF_NOTSC (1 << TIF_NOTSC) 114 #define _TIF_IA32 (1 << TIF_IA32) 115 #define _TIF_FORK (1 << TIF_FORK) 116 #define _TIF_NOHZ (1 << TIF_NOHZ) 117 #define _TIF_DEBUG (1 << TIF_DEBUG) 118 #define _TIF_IO_BITMAP (1 << TIF_IO_BITMAP) 119 #define _TIF_FORCED_TF (1 << TIF_FORCED_TF) 120 #define _TIF_BLOCKSTEP (1 << TIF_BLOCKSTEP) 121 #define _TIF_LAZY_MMU_UPDATES (1 << TIF_LAZY_MMU_UPDATES) 122 #define _TIF_SYSCALL_TRACEPOINT (1 << TIF_SYSCALL_TRACEPOINT) 123 #define _TIF_ADDR32 (1 << TIF_ADDR32) 124 #define _TIF_X32 (1 << TIF_X32) 125 126 /* work to do in syscall_trace_enter() */ 127 #define _TIF_WORK_SYSCALL_ENTRY \ 128 (_TIF_SYSCALL_TRACE | _TIF_SYSCALL_EMU | _TIF_SYSCALL_AUDIT | \ 129 _TIF_SECCOMP | _TIF_SINGLESTEP | _TIF_SYSCALL_TRACEPOINT | \ 130 _TIF_NOHZ) 131 132 /* work to do in syscall_trace_leave() */ 133 #define _TIF_WORK_SYSCALL_EXIT \ 134 (_TIF_SYSCALL_TRACE | _TIF_SYSCALL_AUDIT | _TIF_SINGLESTEP | \ 135 _TIF_SYSCALL_TRACEPOINT | _TIF_NOHZ) 136 137 /* work to do on interrupt/exception return */ 138 #define _TIF_WORK_MASK \ 139 (0x0000FFFF & \ 140 ~(_TIF_SYSCALL_TRACE|_TIF_SYSCALL_AUDIT| \ 141 _TIF_SINGLESTEP|_TIF_SECCOMP|_TIF_SYSCALL_EMU)) 142 143 /* work to do on any return to user space */ 144 #define _TIF_ALLWORK_MASK \ 145 ((0x0000FFFF & ~_TIF_SECCOMP) | _TIF_SYSCALL_TRACEPOINT | \ 146 _TIF_NOHZ) 147 148 /* Only used for 64 bit */ 149 #define _TIF_DO_NOTIFY_MASK \ 150 (_TIF_SIGPENDING | _TIF_MCE_NOTIFY | _TIF_NOTIFY_RESUME | \ 151 _TIF_USER_RETURN_NOTIFY) 152 153 /* flags to check in __switch_to() */ 154 #define _TIF_WORK_CTXSW \ 155 (_TIF_IO_BITMAP|_TIF_NOTSC|_TIF_BLOCKSTEP) 156 157 #define _TIF_WORK_CTXSW_PREV (_TIF_WORK_CTXSW|_TIF_USER_RETURN_NOTIFY) 158 #define _TIF_WORK_CTXSW_NEXT (_TIF_WORK_CTXSW|_TIF_DEBUG) 159 160 #define PREEMPT_ACTIVE 0x10000000 161 162 #ifdef CONFIG_X86_32 163 164 #define STACK_WARN (THREAD_SIZE/8) 165 /* 166 * macros/functions for gaining access to the thread information structure 167 * 168 * preempt_count needs to be 1 initially, until the scheduler is functional. 169 */ 170 #ifndef __ASSEMBLY__ 171 172 173 /* how to get the current stack pointer from C */ 174 register unsigned long current_stack_pointer asm("esp") __used; 175 176 /* how to get the thread information struct from C */ 177 static inline struct thread_info *current_thread_info(void) 178 { 179 return (struct thread_info *) 180 (current_stack_pointer & ~(THREAD_SIZE - 1)); 181 } 182 183 #else /* !__ASSEMBLY__ */ 184 185 /* how to get the thread information struct from ASM */ 186 #define GET_THREAD_INFO(reg) \ 187 movl $-THREAD_SIZE, reg; \ 188 andl %esp, reg 189 190 /* use this one if reg already contains %esp */ 191 #define GET_THREAD_INFO_WITH_ESP(reg) \ 192 andl $-THREAD_SIZE, reg 193 194 #endif 195 196 #else /* X86_32 */ 197 198 #include <asm/percpu.h> 199 #define KERNEL_STACK_OFFSET (5*8) 200 201 /* 202 * macros/functions for gaining access to the thread information structure 203 * preempt_count needs to be 1 initially, until the scheduler is functional. 204 */ 205 #ifndef __ASSEMBLY__ 206 DECLARE_PER_CPU(unsigned long, kernel_stack); 207 208 static inline struct thread_info *current_thread_info(void) 209 { 210 struct thread_info *ti; 211 ti = (void *)(this_cpu_read_stable(kernel_stack) + 212 KERNEL_STACK_OFFSET - THREAD_SIZE); 213 return ti; 214 } 215 216 #else /* !__ASSEMBLY__ */ 217 218 /* how to get the thread information struct from ASM */ 219 #define GET_THREAD_INFO(reg) \ 220 movq PER_CPU_VAR(kernel_stack),reg ; \ 221 subq $(THREAD_SIZE-KERNEL_STACK_OFFSET),reg 222 223 /* 224 * Same if PER_CPU_VAR(kernel_stack) is, perhaps with some offset, already in 225 * a certain register (to be used in assembler memory operands). 226 */ 227 #define THREAD_INFO(reg, off) KERNEL_STACK_OFFSET+(off)-THREAD_SIZE(reg) 228 229 #endif 230 231 #endif /* !X86_32 */ 232 233 /* 234 * Thread-synchronous status. 235 * 236 * This is different from the flags in that nobody else 237 * ever touches our thread-synchronous status, so we don't 238 * have to worry about atomic accesses. 239 */ 240 #define TS_COMPAT 0x0002 /* 32bit syscall active (64BIT)*/ 241 #define TS_POLLING 0x0004 /* idle task polling need_resched, 242 skip sending interrupt */ 243 #define TS_RESTORE_SIGMASK 0x0008 /* restore signal mask in do_signal() */ 244 245 #define tsk_is_polling(t) (task_thread_info(t)->status & TS_POLLING) 246 247 #ifndef __ASSEMBLY__ 248 #define HAVE_SET_RESTORE_SIGMASK 1 249 static inline void set_restore_sigmask(void) 250 { 251 struct thread_info *ti = current_thread_info(); 252 ti->status |= TS_RESTORE_SIGMASK; 253 WARN_ON(!test_bit(TIF_SIGPENDING, (unsigned long *)&ti->flags)); 254 } 255 static inline void clear_restore_sigmask(void) 256 { 257 current_thread_info()->status &= ~TS_RESTORE_SIGMASK; 258 } 259 static inline bool test_restore_sigmask(void) 260 { 261 return current_thread_info()->status & TS_RESTORE_SIGMASK; 262 } 263 static inline bool test_and_clear_restore_sigmask(void) 264 { 265 struct thread_info *ti = current_thread_info(); 266 if (!(ti->status & TS_RESTORE_SIGMASK)) 267 return false; 268 ti->status &= ~TS_RESTORE_SIGMASK; 269 return true; 270 } 271 272 static inline bool is_ia32_task(void) 273 { 274 #ifdef CONFIG_X86_32 275 return true; 276 #endif 277 #ifdef CONFIG_IA32_EMULATION 278 if (current_thread_info()->status & TS_COMPAT) 279 return true; 280 #endif 281 return false; 282 } 283 #endif /* !__ASSEMBLY__ */ 284 285 #ifndef __ASSEMBLY__ 286 extern void arch_task_cache_init(void); 287 extern int arch_dup_task_struct(struct task_struct *dst, struct task_struct *src); 288 extern void arch_release_task_struct(struct task_struct *tsk); 289 #endif 290 #endif /* _ASM_X86_THREAD_INFO_H */ 291