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 <asm/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 int uaccess_err; 44 }; 45 46 #define INIT_THREAD_INFO(tsk) \ 47 { \ 48 .task = &tsk, \ 49 .exec_domain = &default_exec_domain, \ 50 .flags = 0, \ 51 .cpu = 0, \ 52 .preempt_count = INIT_PREEMPT_COUNT, \ 53 .addr_limit = KERNEL_DS, \ 54 .restart_block = { \ 55 .fn = do_no_restart_syscall, \ 56 }, \ 57 } 58 59 #define init_thread_info (init_thread_union.thread_info) 60 #define init_stack (init_thread_union.stack) 61 62 #else /* !__ASSEMBLY__ */ 63 64 #include <asm/asm-offsets.h> 65 66 #endif 67 68 /* 69 * thread information flags 70 * - these are process state flags that various assembly files 71 * may need to access 72 * - pending work-to-be-done flags are in LSW 73 * - other flags in MSW 74 * Warning: layout of LSW is hardcoded in entry.S 75 */ 76 #define TIF_SYSCALL_TRACE 0 /* syscall trace active */ 77 #define TIF_NOTIFY_RESUME 1 /* callback before returning to user */ 78 #define TIF_SIGPENDING 2 /* signal pending */ 79 #define TIF_NEED_RESCHED 3 /* rescheduling necessary */ 80 #define TIF_SINGLESTEP 4 /* reenable singlestep on user return*/ 81 #define TIF_IRET 5 /* force IRET */ 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_NOTSC 16 /* TSC is not accessible in userland */ 87 #define TIF_IA32 17 /* 32bit process */ 88 #define TIF_FORK 18 /* ret_from_fork */ 89 #define TIF_ABI_PENDING 19 90 #define TIF_MEMDIE 20 91 #define TIF_DEBUG 21 /* uses debug registers */ 92 #define TIF_IO_BITMAP 22 /* uses I/O bitmap */ 93 #define TIF_FREEZE 23 /* is freezing for suspend */ 94 #define TIF_FORCED_TF 24 /* true if TF in eflags artificially */ 95 #define TIF_DEBUGCTLMSR 25 /* uses thread_struct.debugctlmsr */ 96 #define TIF_DS_AREA_MSR 26 /* uses thread_struct.ds_area_msr */ 97 #define TIF_LAZY_MMU_UPDATES 27 /* task is updating the mmu lazily */ 98 #define TIF_SYSCALL_FTRACE 28 /* for ftrace syscall instrumentation */ 99 100 #define _TIF_SYSCALL_TRACE (1 << TIF_SYSCALL_TRACE) 101 #define _TIF_NOTIFY_RESUME (1 << TIF_NOTIFY_RESUME) 102 #define _TIF_SIGPENDING (1 << TIF_SIGPENDING) 103 #define _TIF_SINGLESTEP (1 << TIF_SINGLESTEP) 104 #define _TIF_NEED_RESCHED (1 << TIF_NEED_RESCHED) 105 #define _TIF_IRET (1 << TIF_IRET) 106 #define _TIF_SYSCALL_EMU (1 << TIF_SYSCALL_EMU) 107 #define _TIF_SYSCALL_AUDIT (1 << TIF_SYSCALL_AUDIT) 108 #define _TIF_SECCOMP (1 << TIF_SECCOMP) 109 #define _TIF_MCE_NOTIFY (1 << TIF_MCE_NOTIFY) 110 #define _TIF_NOTSC (1 << TIF_NOTSC) 111 #define _TIF_IA32 (1 << TIF_IA32) 112 #define _TIF_FORK (1 << TIF_FORK) 113 #define _TIF_ABI_PENDING (1 << TIF_ABI_PENDING) 114 #define _TIF_DEBUG (1 << TIF_DEBUG) 115 #define _TIF_IO_BITMAP (1 << TIF_IO_BITMAP) 116 #define _TIF_FREEZE (1 << TIF_FREEZE) 117 #define _TIF_FORCED_TF (1 << TIF_FORCED_TF) 118 #define _TIF_DEBUGCTLMSR (1 << TIF_DEBUGCTLMSR) 119 #define _TIF_DS_AREA_MSR (1 << TIF_DS_AREA_MSR) 120 #define _TIF_LAZY_MMU_UPDATES (1 << TIF_LAZY_MMU_UPDATES) 121 #define _TIF_SYSCALL_FTRACE (1 << TIF_SYSCALL_FTRACE) 122 123 /* work to do in syscall_trace_enter() */ 124 #define _TIF_WORK_SYSCALL_ENTRY \ 125 (_TIF_SYSCALL_TRACE | _TIF_SYSCALL_EMU | _TIF_SYSCALL_FTRACE | \ 126 _TIF_SYSCALL_AUDIT | _TIF_SECCOMP | _TIF_SINGLESTEP) 127 128 /* work to do in syscall_trace_leave() */ 129 #define _TIF_WORK_SYSCALL_EXIT \ 130 (_TIF_SYSCALL_TRACE | _TIF_SYSCALL_AUDIT | _TIF_SINGLESTEP | \ 131 _TIF_SYSCALL_FTRACE) 132 133 /* work to do on interrupt/exception return */ 134 #define _TIF_WORK_MASK \ 135 (0x0000FFFF & \ 136 ~(_TIF_SYSCALL_TRACE|_TIF_SYSCALL_AUDIT| \ 137 _TIF_SINGLESTEP|_TIF_SECCOMP|_TIF_SYSCALL_EMU)) 138 139 /* work to do on any return to user space */ 140 #define _TIF_ALLWORK_MASK ((0x0000FFFF & ~_TIF_SECCOMP) | _TIF_SYSCALL_FTRACE) 141 142 /* Only used for 64 bit */ 143 #define _TIF_DO_NOTIFY_MASK \ 144 (_TIF_SIGPENDING|_TIF_MCE_NOTIFY|_TIF_NOTIFY_RESUME) 145 146 /* flags to check in __switch_to() */ 147 #define _TIF_WORK_CTXSW \ 148 (_TIF_IO_BITMAP|_TIF_DEBUGCTLMSR|_TIF_DS_AREA_MSR|_TIF_NOTSC) 149 150 #define _TIF_WORK_CTXSW_PREV _TIF_WORK_CTXSW 151 #define _TIF_WORK_CTXSW_NEXT (_TIF_WORK_CTXSW|_TIF_DEBUG) 152 153 #define PREEMPT_ACTIVE 0x10000000 154 155 /* thread information allocation */ 156 #ifdef CONFIG_DEBUG_STACK_USAGE 157 #define THREAD_FLAGS (GFP_KERNEL | __GFP_NOTRACK | __GFP_ZERO) 158 #else 159 #define THREAD_FLAGS (GFP_KERNEL | __GFP_NOTRACK) 160 #endif 161 162 #define __HAVE_ARCH_THREAD_INFO_ALLOCATOR 163 164 #define alloc_thread_info(tsk) \ 165 ((struct thread_info *)__get_free_pages(THREAD_FLAGS, THREAD_ORDER)) 166 167 #ifdef CONFIG_X86_32 168 169 #define STACK_WARN (THREAD_SIZE/8) 170 /* 171 * macros/functions for gaining access to the thread information structure 172 * 173 * preempt_count needs to be 1 initially, until the scheduler is functional. 174 */ 175 #ifndef __ASSEMBLY__ 176 177 178 /* how to get the current stack pointer from C */ 179 register unsigned long current_stack_pointer asm("esp") __used; 180 181 /* how to get the thread information struct from C */ 182 static inline struct thread_info *current_thread_info(void) 183 { 184 return (struct thread_info *) 185 (current_stack_pointer & ~(THREAD_SIZE - 1)); 186 } 187 188 #else /* !__ASSEMBLY__ */ 189 190 /* how to get the thread information struct from ASM */ 191 #define GET_THREAD_INFO(reg) \ 192 movl $-THREAD_SIZE, reg; \ 193 andl %esp, reg 194 195 /* use this one if reg already contains %esp */ 196 #define GET_THREAD_INFO_WITH_ESP(reg) \ 197 andl $-THREAD_SIZE, reg 198 199 #endif 200 201 #else /* X86_32 */ 202 203 #include <asm/percpu.h> 204 #define KERNEL_STACK_OFFSET (5*8) 205 206 /* 207 * macros/functions for gaining access to the thread information structure 208 * preempt_count needs to be 1 initially, until the scheduler is functional. 209 */ 210 #ifndef __ASSEMBLY__ 211 DECLARE_PER_CPU(unsigned long, kernel_stack); 212 213 static inline struct thread_info *current_thread_info(void) 214 { 215 struct thread_info *ti; 216 ti = (void *)(percpu_read_stable(kernel_stack) + 217 KERNEL_STACK_OFFSET - THREAD_SIZE); 218 return ti; 219 } 220 221 #else /* !__ASSEMBLY__ */ 222 223 /* how to get the thread information struct from ASM */ 224 #define GET_THREAD_INFO(reg) \ 225 movq PER_CPU_VAR(kernel_stack),reg ; \ 226 subq $(THREAD_SIZE-KERNEL_STACK_OFFSET),reg 227 228 #endif 229 230 #endif /* !X86_32 */ 231 232 /* 233 * Thread-synchronous status. 234 * 235 * This is different from the flags in that nobody else 236 * ever touches our thread-synchronous status, so we don't 237 * have to worry about atomic accesses. 238 */ 239 #define TS_USEDFPU 0x0001 /* FPU was used by this task 240 this quantum (SMP) */ 241 #define TS_COMPAT 0x0002 /* 32bit syscall active (64BIT)*/ 242 #define TS_POLLING 0x0004 /* true if in idle loop 243 and not sleeping */ 244 #define TS_RESTORE_SIGMASK 0x0008 /* restore signal mask in do_signal() */ 245 #define TS_XSAVE 0x0010 /* Use xsave/xrstor */ 246 247 #define tsk_is_polling(t) (task_thread_info(t)->status & TS_POLLING) 248 249 #ifndef __ASSEMBLY__ 250 #define HAVE_SET_RESTORE_SIGMASK 1 251 static inline void set_restore_sigmask(void) 252 { 253 struct thread_info *ti = current_thread_info(); 254 ti->status |= TS_RESTORE_SIGMASK; 255 set_bit(TIF_SIGPENDING, (unsigned long *)&ti->flags); 256 } 257 #endif /* !__ASSEMBLY__ */ 258 259 #ifndef __ASSEMBLY__ 260 extern void arch_task_cache_init(void); 261 extern void free_thread_info(struct thread_info *ti); 262 extern int arch_dup_task_struct(struct task_struct *dst, struct task_struct *src); 263 #define arch_task_cache_init arch_task_cache_init 264 #endif 265 #endif /* _ASM_X86_THREAD_INFO_H */ 266