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 24 struct thread_info { 25 struct task_struct *task; /* main task structure */ 26 struct exec_domain *exec_domain; /* execution domain */ 27 unsigned long flags; /* low level flags */ 28 __u32 status; /* thread synchronous flags */ 29 __u32 cpu; /* current CPU */ 30 int preempt_count; /* 0 => preemptable, 31 <0 => BUG */ 32 mm_segment_t addr_limit; 33 struct restart_block restart_block; 34 void __user *sysenter_return; 35 #ifdef CONFIG_X86_32 36 unsigned long previous_esp; /* ESP of the previous stack in 37 case of nested (IRQ) stacks 38 */ 39 __u8 supervisor_stack[0]; 40 #endif 41 }; 42 43 #define INIT_THREAD_INFO(tsk) \ 44 { \ 45 .task = &tsk, \ 46 .exec_domain = &default_exec_domain, \ 47 .flags = 0, \ 48 .cpu = 0, \ 49 .preempt_count = 1, \ 50 .addr_limit = KERNEL_DS, \ 51 .restart_block = { \ 52 .fn = do_no_restart_syscall, \ 53 }, \ 54 } 55 56 #define init_thread_info (init_thread_union.thread_info) 57 #define init_stack (init_thread_union.stack) 58 59 #else /* !__ASSEMBLY__ */ 60 61 #include <asm/asm-offsets.h> 62 63 #endif 64 65 /* 66 * thread information flags 67 * - these are process state flags that various assembly files 68 * may need to access 69 * - pending work-to-be-done flags are in LSW 70 * - other flags in MSW 71 * Warning: layout of LSW is hardcoded in entry.S 72 */ 73 #define TIF_SYSCALL_TRACE 0 /* syscall trace active */ 74 #define TIF_NOTIFY_RESUME 1 /* callback before returning to user */ 75 #define TIF_SIGPENDING 2 /* signal pending */ 76 #define TIF_NEED_RESCHED 3 /* rescheduling necessary */ 77 #define TIF_SINGLESTEP 4 /* reenable singlestep on user return*/ 78 #define TIF_IRET 5 /* force IRET */ 79 #define TIF_SYSCALL_EMU 6 /* syscall emulation active */ 80 #define TIF_SYSCALL_AUDIT 7 /* syscall auditing active */ 81 #define TIF_SECCOMP 8 /* secure computing */ 82 #define TIF_MCE_NOTIFY 10 /* notify userspace of an MCE */ 83 #define TIF_NOTSC 16 /* TSC is not accessible in userland */ 84 #define TIF_IA32 17 /* 32bit process */ 85 #define TIF_FORK 18 /* ret_from_fork */ 86 #define TIF_ABI_PENDING 19 87 #define TIF_MEMDIE 20 88 #define TIF_DEBUG 21 /* uses debug registers */ 89 #define TIF_IO_BITMAP 22 /* uses I/O bitmap */ 90 #define TIF_FREEZE 23 /* is freezing for suspend */ 91 #define TIF_FORCED_TF 24 /* true if TF in eflags artificially */ 92 #define TIF_DEBUGCTLMSR 25 /* uses thread_struct.debugctlmsr */ 93 #define TIF_DS_AREA_MSR 26 /* uses thread_struct.ds_area_msr */ 94 #define TIF_BTS_TRACE_TS 27 /* record scheduling event timestamps */ 95 96 #define _TIF_SYSCALL_TRACE (1 << TIF_SYSCALL_TRACE) 97 #define _TIF_NOTIFY_RESUME (1 << TIF_NOTIFY_RESUME) 98 #define _TIF_SIGPENDING (1 << TIF_SIGPENDING) 99 #define _TIF_SINGLESTEP (1 << TIF_SINGLESTEP) 100 #define _TIF_NEED_RESCHED (1 << TIF_NEED_RESCHED) 101 #define _TIF_IRET (1 << TIF_IRET) 102 #define _TIF_SYSCALL_EMU (1 << TIF_SYSCALL_EMU) 103 #define _TIF_SYSCALL_AUDIT (1 << TIF_SYSCALL_AUDIT) 104 #define _TIF_SECCOMP (1 << TIF_SECCOMP) 105 #define _TIF_MCE_NOTIFY (1 << TIF_MCE_NOTIFY) 106 #define _TIF_NOTSC (1 << TIF_NOTSC) 107 #define _TIF_IA32 (1 << TIF_IA32) 108 #define _TIF_FORK (1 << TIF_FORK) 109 #define _TIF_ABI_PENDING (1 << TIF_ABI_PENDING) 110 #define _TIF_DEBUG (1 << TIF_DEBUG) 111 #define _TIF_IO_BITMAP (1 << TIF_IO_BITMAP) 112 #define _TIF_FREEZE (1 << TIF_FREEZE) 113 #define _TIF_FORCED_TF (1 << TIF_FORCED_TF) 114 #define _TIF_DEBUGCTLMSR (1 << TIF_DEBUGCTLMSR) 115 #define _TIF_DS_AREA_MSR (1 << TIF_DS_AREA_MSR) 116 #define _TIF_BTS_TRACE_TS (1 << TIF_BTS_TRACE_TS) 117 118 /* work to do in syscall_trace_enter() */ 119 #define _TIF_WORK_SYSCALL_ENTRY \ 120 (_TIF_SYSCALL_TRACE | _TIF_SYSCALL_EMU | \ 121 _TIF_SYSCALL_AUDIT | _TIF_SECCOMP | _TIF_SINGLESTEP) 122 123 /* work to do in syscall_trace_leave() */ 124 #define _TIF_WORK_SYSCALL_EXIT \ 125 (_TIF_SYSCALL_TRACE | _TIF_SYSCALL_AUDIT | _TIF_SINGLESTEP) 126 127 /* work to do on interrupt/exception return */ 128 #define _TIF_WORK_MASK \ 129 (0x0000FFFF & \ 130 ~(_TIF_SYSCALL_TRACE|_TIF_SYSCALL_AUDIT| \ 131 _TIF_SINGLESTEP|_TIF_SECCOMP|_TIF_SYSCALL_EMU)) 132 133 /* work to do on any return to user space */ 134 #define _TIF_ALLWORK_MASK (0x0000FFFF & ~_TIF_SECCOMP) 135 136 /* Only used for 64 bit */ 137 #define _TIF_DO_NOTIFY_MASK \ 138 (_TIF_SIGPENDING|_TIF_MCE_NOTIFY|_TIF_NOTIFY_RESUME) 139 140 /* flags to check in __switch_to() */ 141 #define _TIF_WORK_CTXSW \ 142 (_TIF_IO_BITMAP|_TIF_DEBUGCTLMSR|_TIF_DS_AREA_MSR|_TIF_BTS_TRACE_TS| \ 143 _TIF_NOTSC) 144 145 #define _TIF_WORK_CTXSW_PREV _TIF_WORK_CTXSW 146 #define _TIF_WORK_CTXSW_NEXT (_TIF_WORK_CTXSW|_TIF_DEBUG) 147 148 #define PREEMPT_ACTIVE 0x10000000 149 150 /* thread information allocation */ 151 #ifdef CONFIG_DEBUG_STACK_USAGE 152 #define THREAD_FLAGS (GFP_KERNEL | __GFP_ZERO) 153 #else 154 #define THREAD_FLAGS GFP_KERNEL 155 #endif 156 157 #define __HAVE_ARCH_THREAD_INFO_ALLOCATOR 158 159 #define alloc_thread_info(tsk) \ 160 ((struct thread_info *)__get_free_pages(THREAD_FLAGS, THREAD_ORDER)) 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/pda.h> 199 200 /* 201 * macros/functions for gaining access to the thread information structure 202 * preempt_count needs to be 1 initially, until the scheduler is functional. 203 */ 204 #ifndef __ASSEMBLY__ 205 static inline struct thread_info *current_thread_info(void) 206 { 207 struct thread_info *ti; 208 ti = (void *)(read_pda(kernelstack) + PDA_STACKOFFSET - THREAD_SIZE); 209 return ti; 210 } 211 212 /* do not use in interrupt context */ 213 static inline struct thread_info *stack_thread_info(void) 214 { 215 struct thread_info *ti; 216 asm("andq %%rsp,%0; " : "=r" (ti) : "0" (~(THREAD_SIZE - 1))); 217 return ti; 218 } 219 220 #else /* !__ASSEMBLY__ */ 221 222 /* how to get the thread information struct from ASM */ 223 #define GET_THREAD_INFO(reg) \ 224 movq %gs:pda_kernelstack,reg ; \ 225 subq $(THREAD_SIZE-PDA_STACKOFFSET),reg 226 227 #endif 228 229 #endif /* !X86_32 */ 230 231 /* 232 * Thread-synchronous status. 233 * 234 * This is different from the flags in that nobody else 235 * ever touches our thread-synchronous status, so we don't 236 * have to worry about atomic accesses. 237 */ 238 #define TS_USEDFPU 0x0001 /* FPU was used by this task 239 this quantum (SMP) */ 240 #define TS_COMPAT 0x0002 /* 32bit syscall active (64BIT)*/ 241 #define TS_POLLING 0x0004 /* true if in idle loop 242 and not sleeping */ 243 #define TS_RESTORE_SIGMASK 0x0008 /* restore signal mask in do_signal() */ 244 #define TS_XSAVE 0x0010 /* Use xsave/xrstor */ 245 246 #define tsk_is_polling(t) (task_thread_info(t)->status & TS_POLLING) 247 248 #ifndef __ASSEMBLY__ 249 #define HAVE_SET_RESTORE_SIGMASK 1 250 static inline void set_restore_sigmask(void) 251 { 252 struct thread_info *ti = current_thread_info(); 253 ti->status |= TS_RESTORE_SIGMASK; 254 set_bit(TIF_SIGPENDING, (unsigned long *)&ti->flags); 255 } 256 #endif /* !__ASSEMBLY__ */ 257 258 #ifndef __ASSEMBLY__ 259 extern void arch_task_cache_init(void); 260 extern void free_thread_info(struct thread_info *ti); 261 extern int arch_dup_task_struct(struct task_struct *dst, struct task_struct *src); 262 #define arch_task_cache_init arch_task_cache_init 263 #endif 264 #endif /* _ASM_X86_THREAD_INFO_H */ 265