1 /* 2 * include/asm-xtensa/thread_info.h 3 * 4 * This file is subject to the terms and conditions of the GNU General Public 5 * License. See the file "COPYING" in the main directory of this archive 6 * for more details. 7 * 8 * Copyright (C) 2001 - 2005 Tensilica Inc. 9 */ 10 11 #ifndef _XTENSA_THREAD_INFO_H 12 #define _XTENSA_THREAD_INFO_H 13 14 #include <asm/kmem_layout.h> 15 16 #define CURRENT_SHIFT KERNEL_STACK_SHIFT 17 18 #ifndef __ASSEMBLY__ 19 # include <asm/processor.h> 20 #endif 21 22 /* 23 * low level task data that entry.S needs immediate access to 24 * - this struct should fit entirely inside of one cache line 25 * - this struct shares the supervisor stack pages 26 * - if the contents of this structure are changed, the assembly constants 27 * must also be changed 28 */ 29 30 #ifndef __ASSEMBLY__ 31 32 #if XTENSA_HAVE_COPROCESSORS 33 34 typedef struct xtregs_coprocessor { 35 xtregs_cp0_t cp0; 36 xtregs_cp1_t cp1; 37 xtregs_cp2_t cp2; 38 xtregs_cp3_t cp3; 39 xtregs_cp4_t cp4; 40 xtregs_cp5_t cp5; 41 xtregs_cp6_t cp6; 42 xtregs_cp7_t cp7; 43 } xtregs_coprocessor_t; 44 45 #endif 46 47 struct thread_info { 48 struct task_struct *task; /* main task structure */ 49 unsigned long flags; /* low level flags */ 50 unsigned long status; /* thread-synchronous flags */ 51 __u32 cpu; /* current CPU */ 52 __s32 preempt_count; /* 0 => preemptable,< 0 => BUG*/ 53 54 mm_segment_t addr_limit; /* thread address space */ 55 56 unsigned long cpenable; 57 58 /* Allocate storage for extra user states and coprocessor states. */ 59 #if XTENSA_HAVE_COPROCESSORS 60 xtregs_coprocessor_t xtregs_cp; 61 #endif 62 xtregs_user_t xtregs_user; 63 }; 64 65 #endif 66 67 /* 68 * macros/functions for gaining access to the thread information structure 69 */ 70 71 #ifndef __ASSEMBLY__ 72 73 #define INIT_THREAD_INFO(tsk) \ 74 { \ 75 .task = &tsk, \ 76 .flags = 0, \ 77 .cpu = 0, \ 78 .preempt_count = INIT_PREEMPT_COUNT, \ 79 .addr_limit = KERNEL_DS, \ 80 } 81 82 #define init_thread_info (init_thread_union.thread_info) 83 #define init_stack (init_thread_union.stack) 84 85 /* how to get the thread information struct from C */ 86 static inline struct thread_info *current_thread_info(void) 87 { 88 struct thread_info *ti; 89 __asm__("extui %0, a1, 0, "__stringify(CURRENT_SHIFT)"\n\t" 90 "xor %0, a1, %0" : "=&r" (ti) : ); 91 return ti; 92 } 93 94 #else /* !__ASSEMBLY__ */ 95 96 /* how to get the thread information struct from ASM */ 97 #define GET_THREAD_INFO(reg,sp) \ 98 extui reg, sp, 0, CURRENT_SHIFT; \ 99 xor reg, sp, reg 100 #endif 101 102 103 /* 104 * thread information flags 105 * - these are process state flags that various assembly files may need to access 106 * - pending work-to-be-done flags are in LSW 107 * - other flags in MSW 108 */ 109 #define TIF_SYSCALL_TRACE 0 /* syscall trace active */ 110 #define TIF_SIGPENDING 1 /* signal pending */ 111 #define TIF_NEED_RESCHED 2 /* rescheduling necessary */ 112 #define TIF_SINGLESTEP 3 /* restore singlestep on return to user mode */ 113 #define TIF_MEMDIE 5 /* is terminating due to OOM killer */ 114 #define TIF_RESTORE_SIGMASK 6 /* restore signal mask in do_signal() */ 115 #define TIF_NOTIFY_RESUME 7 /* callback before returning to user */ 116 #define TIF_DB_DISABLED 8 /* debug trap disabled for syscall */ 117 118 #define _TIF_SYSCALL_TRACE (1<<TIF_SYSCALL_TRACE) 119 #define _TIF_SIGPENDING (1<<TIF_SIGPENDING) 120 #define _TIF_NEED_RESCHED (1<<TIF_NEED_RESCHED) 121 #define _TIF_SINGLESTEP (1<<TIF_SINGLESTEP) 122 123 #define _TIF_WORK_MASK 0x0000FFFE /* work to do on interrupt/exception return */ 124 #define _TIF_ALLWORK_MASK 0x0000FFFF /* work to do on any return to u-space */ 125 126 /* 127 * Thread-synchronous status. 128 * 129 * This is different from the flags in that nobody else 130 * ever touches our thread-synchronous status, so we don't 131 * have to worry about atomic accesses. 132 */ 133 #define TS_USEDFPU 0x0001 /* FPU was used by this task this quantum (SMP) */ 134 135 #define THREAD_SIZE KERNEL_STACK_SIZE 136 #define THREAD_SIZE_ORDER (KERNEL_STACK_SHIFT - PAGE_SHIFT) 137 138 #endif /* _XTENSA_THREAD_INFO */ 139