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 void __user *sysenter_return; 35 unsigned int sig_on_uaccess_error:1; 36 unsigned int uaccess_err:1; /* uaccess failed */ 37 }; 38 39 #define INIT_THREAD_INFO(tsk) \ 40 { \ 41 .task = &tsk, \ 42 .exec_domain = &default_exec_domain, \ 43 .flags = 0, \ 44 .cpu = 0, \ 45 .saved_preempt_count = INIT_PREEMPT_COUNT, \ 46 .addr_limit = KERNEL_DS, \ 47 } 48 49 #define init_thread_info (init_thread_union.thread_info) 50 #define init_stack (init_thread_union.stack) 51 52 #else /* !__ASSEMBLY__ */ 53 54 #include <asm/asm-offsets.h> 55 56 #endif 57 58 /* 59 * thread information flags 60 * - these are process state flags that various assembly files 61 * may need to access 62 * - pending work-to-be-done flags are in LSW 63 * - other flags in MSW 64 * Warning: layout of LSW is hardcoded in entry.S 65 */ 66 #define TIF_SYSCALL_TRACE 0 /* syscall trace active */ 67 #define TIF_NOTIFY_RESUME 1 /* callback before returning to user */ 68 #define TIF_SIGPENDING 2 /* signal pending */ 69 #define TIF_NEED_RESCHED 3 /* rescheduling necessary */ 70 #define TIF_SINGLESTEP 4 /* reenable singlestep on user return*/ 71 #define TIF_SYSCALL_EMU 6 /* syscall emulation active */ 72 #define TIF_SYSCALL_AUDIT 7 /* syscall auditing active */ 73 #define TIF_SECCOMP 8 /* secure computing */ 74 #define TIF_USER_RETURN_NOTIFY 11 /* notify kernel of userspace return */ 75 #define TIF_UPROBE 12 /* breakpointed or singlestepping */ 76 #define TIF_NOTSC 16 /* TSC is not accessible in userland */ 77 #define TIF_IA32 17 /* IA32 compatibility process */ 78 #define TIF_FORK 18 /* ret_from_fork */ 79 #define TIF_NOHZ 19 /* in adaptive nohz mode */ 80 #define TIF_MEMDIE 20 /* is terminating due to OOM killer */ 81 #define TIF_POLLING_NRFLAG 21 /* idle is polling for TIF_NEED_RESCHED */ 82 #define TIF_IO_BITMAP 22 /* uses I/O bitmap */ 83 #define TIF_FORCED_TF 24 /* true if TF in eflags artificially */ 84 #define TIF_BLOCKSTEP 25 /* set when we want DEBUGCTLMSR_BTF */ 85 #define TIF_LAZY_MMU_UPDATES 27 /* task is updating the mmu lazily */ 86 #define TIF_SYSCALL_TRACEPOINT 28 /* syscall tracepoint instrumentation */ 87 #define TIF_ADDR32 29 /* 32-bit address space on 64 bits */ 88 #define TIF_X32 30 /* 32-bit native x86-64 binary */ 89 90 #define _TIF_SYSCALL_TRACE (1 << TIF_SYSCALL_TRACE) 91 #define _TIF_NOTIFY_RESUME (1 << TIF_NOTIFY_RESUME) 92 #define _TIF_SIGPENDING (1 << TIF_SIGPENDING) 93 #define _TIF_SINGLESTEP (1 << TIF_SINGLESTEP) 94 #define _TIF_NEED_RESCHED (1 << TIF_NEED_RESCHED) 95 #define _TIF_SYSCALL_EMU (1 << TIF_SYSCALL_EMU) 96 #define _TIF_SYSCALL_AUDIT (1 << TIF_SYSCALL_AUDIT) 97 #define _TIF_SECCOMP (1 << TIF_SECCOMP) 98 #define _TIF_USER_RETURN_NOTIFY (1 << TIF_USER_RETURN_NOTIFY) 99 #define _TIF_UPROBE (1 << TIF_UPROBE) 100 #define _TIF_NOTSC (1 << TIF_NOTSC) 101 #define _TIF_IA32 (1 << TIF_IA32) 102 #define _TIF_FORK (1 << TIF_FORK) 103 #define _TIF_NOHZ (1 << TIF_NOHZ) 104 #define _TIF_POLLING_NRFLAG (1 << TIF_POLLING_NRFLAG) 105 #define _TIF_IO_BITMAP (1 << TIF_IO_BITMAP) 106 #define _TIF_FORCED_TF (1 << TIF_FORCED_TF) 107 #define _TIF_BLOCKSTEP (1 << TIF_BLOCKSTEP) 108 #define _TIF_LAZY_MMU_UPDATES (1 << TIF_LAZY_MMU_UPDATES) 109 #define _TIF_SYSCALL_TRACEPOINT (1 << TIF_SYSCALL_TRACEPOINT) 110 #define _TIF_ADDR32 (1 << TIF_ADDR32) 111 #define _TIF_X32 (1 << TIF_X32) 112 113 /* work to do in syscall_trace_enter() */ 114 #define _TIF_WORK_SYSCALL_ENTRY \ 115 (_TIF_SYSCALL_TRACE | _TIF_SYSCALL_EMU | _TIF_SYSCALL_AUDIT | \ 116 _TIF_SECCOMP | _TIF_SINGLESTEP | _TIF_SYSCALL_TRACEPOINT | \ 117 _TIF_NOHZ) 118 119 /* work to do in syscall_trace_leave() */ 120 #define _TIF_WORK_SYSCALL_EXIT \ 121 (_TIF_SYSCALL_TRACE | _TIF_SYSCALL_AUDIT | _TIF_SINGLESTEP | \ 122 _TIF_SYSCALL_TRACEPOINT | _TIF_NOHZ) 123 124 /* work to do on interrupt/exception return */ 125 #define _TIF_WORK_MASK \ 126 (0x0000FFFF & \ 127 ~(_TIF_SYSCALL_TRACE|_TIF_SYSCALL_AUDIT| \ 128 _TIF_SINGLESTEP|_TIF_SECCOMP|_TIF_SYSCALL_EMU)) 129 130 /* work to do on any return to user space */ 131 #define _TIF_ALLWORK_MASK \ 132 ((0x0000FFFF & ~_TIF_SECCOMP) | _TIF_SYSCALL_TRACEPOINT | \ 133 _TIF_NOHZ) 134 135 /* Only used for 64 bit */ 136 #define _TIF_DO_NOTIFY_MASK \ 137 (_TIF_SIGPENDING | _TIF_NOTIFY_RESUME | \ 138 _TIF_USER_RETURN_NOTIFY | _TIF_UPROBE) 139 140 /* flags to check in __switch_to() */ 141 #define _TIF_WORK_CTXSW \ 142 (_TIF_IO_BITMAP|_TIF_NOTSC|_TIF_BLOCKSTEP) 143 144 #define _TIF_WORK_CTXSW_PREV (_TIF_WORK_CTXSW|_TIF_USER_RETURN_NOTIFY) 145 #define _TIF_WORK_CTXSW_NEXT (_TIF_WORK_CTXSW) 146 147 #define STACK_WARN (THREAD_SIZE/8) 148 #define KERNEL_STACK_OFFSET (5*(BITS_PER_LONG/8)) 149 150 /* 151 * macros/functions for gaining access to the thread information structure 152 * 153 * preempt_count needs to be 1 initially, until the scheduler is functional. 154 */ 155 #ifndef __ASSEMBLY__ 156 157 DECLARE_PER_CPU(unsigned long, kernel_stack); 158 159 static inline struct thread_info *current_thread_info(void) 160 { 161 struct thread_info *ti; 162 ti = (void *)(this_cpu_read_stable(kernel_stack) + 163 KERNEL_STACK_OFFSET - THREAD_SIZE); 164 return ti; 165 } 166 167 static inline unsigned long current_stack_pointer(void) 168 { 169 unsigned long sp; 170 #ifdef CONFIG_X86_64 171 asm("mov %%rsp,%0" : "=g" (sp)); 172 #else 173 asm("mov %%esp,%0" : "=g" (sp)); 174 #endif 175 return sp; 176 } 177 178 #else /* !__ASSEMBLY__ */ 179 180 /* how to get the thread information struct from ASM */ 181 #define GET_THREAD_INFO(reg) \ 182 _ASM_MOV PER_CPU_VAR(kernel_stack),reg ; \ 183 _ASM_SUB $(THREAD_SIZE-KERNEL_STACK_OFFSET),reg ; 184 185 /* 186 * Same if PER_CPU_VAR(kernel_stack) is, perhaps with some offset, already in 187 * a certain register (to be used in assembler memory operands). 188 */ 189 #define THREAD_INFO(reg, off) KERNEL_STACK_OFFSET+(off)-THREAD_SIZE(reg) 190 191 #endif 192 193 /* 194 * Thread-synchronous status. 195 * 196 * This is different from the flags in that nobody else 197 * ever touches our thread-synchronous status, so we don't 198 * have to worry about atomic accesses. 199 */ 200 #define TS_COMPAT 0x0002 /* 32bit syscall active (64BIT)*/ 201 #define TS_RESTORE_SIGMASK 0x0008 /* restore signal mask in do_signal() */ 202 203 #ifndef __ASSEMBLY__ 204 #define HAVE_SET_RESTORE_SIGMASK 1 205 static inline void set_restore_sigmask(void) 206 { 207 struct thread_info *ti = current_thread_info(); 208 ti->status |= TS_RESTORE_SIGMASK; 209 WARN_ON(!test_bit(TIF_SIGPENDING, (unsigned long *)&ti->flags)); 210 } 211 static inline void clear_restore_sigmask(void) 212 { 213 current_thread_info()->status &= ~TS_RESTORE_SIGMASK; 214 } 215 static inline bool test_restore_sigmask(void) 216 { 217 return current_thread_info()->status & TS_RESTORE_SIGMASK; 218 } 219 static inline bool test_and_clear_restore_sigmask(void) 220 { 221 struct thread_info *ti = current_thread_info(); 222 if (!(ti->status & TS_RESTORE_SIGMASK)) 223 return false; 224 ti->status &= ~TS_RESTORE_SIGMASK; 225 return true; 226 } 227 228 static inline bool is_ia32_task(void) 229 { 230 #ifdef CONFIG_X86_32 231 return true; 232 #endif 233 #ifdef CONFIG_IA32_EMULATION 234 if (current_thread_info()->status & TS_COMPAT) 235 return true; 236 #endif 237 return false; 238 } 239 #endif /* !__ASSEMBLY__ */ 240 241 #ifndef __ASSEMBLY__ 242 extern void arch_task_cache_init(void); 243 extern int arch_dup_task_struct(struct task_struct *dst, struct task_struct *src); 244 extern void arch_release_task_struct(struct task_struct *tsk); 245 #endif 246 #endif /* _ASM_X86_THREAD_INFO_H */ 247