1/* 2 * Thread support for the Hexagon architecture 3 * 4 * Copyright (c) 2010-2011, The Linux Foundation. All rights reserved. 5 * 6 * This program is free software; you can redistribute it and/or modify 7 * it under the terms of the GNU General Public License version 2 and 8 * only version 2 as published by the Free Software Foundation. 9 * 10 * This program is distributed in the hope that it will be useful, 11 * but WITHOUT ANY WARRANTY; without even the implied warranty of 12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 13 * GNU General Public License for more details. 14 * 15 * You should have received a copy of the GNU General Public License 16 * along with this program; if not, write to the Free Software 17 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 18 * 02110-1301, USA. 19 */ 20 21#ifndef _ASM_THREAD_INFO_H 22#define _ASM_THREAD_INFO_H 23 24#ifdef __KERNEL__ 25 26#ifndef __ASSEMBLY__ 27#include <asm/processor.h> 28#include <asm/registers.h> 29#include <asm/page.h> 30#endif 31 32#define THREAD_SHIFT 12 33#define THREAD_SIZE (1<<THREAD_SHIFT) 34#define THREAD_SIZE_ORDER (THREAD_SHIFT - PAGE_SHIFT) 35 36#ifndef __ASSEMBLY__ 37 38typedef struct { 39 unsigned long seg; 40} mm_segment_t; 41 42/* 43 * This is union'd with the "bottom" of the kernel stack. 44 * It keeps track of thread info which is handy for routines 45 * to access quickly. 46 */ 47 48struct thread_info { 49 struct task_struct *task; /* main task structure */ 50 unsigned long flags; /* low level flags */ 51 __u32 cpu; /* current cpu */ 52 int preempt_count; /* 0=>preemptible,<0=>BUG */ 53 mm_segment_t addr_limit; /* segmentation sux */ 54 /* 55 * used for syscalls somehow; 56 * seems to have a function pointer and four arguments 57 */ 58 /* Points to the current pt_regs frame */ 59 struct pt_regs *regs; 60 /* 61 * saved kernel sp at switch_to time; 62 * not sure if this is used (it's not in the VM model it seems; 63 * see thread_struct) 64 */ 65 unsigned long sp; 66}; 67 68#else /* !__ASSEMBLY__ */ 69 70#include <asm/asm-offsets.h> 71 72#endif /* __ASSEMBLY__ */ 73 74#ifndef __ASSEMBLY__ 75 76#define INIT_THREAD_INFO(tsk) \ 77{ \ 78 .task = &tsk, \ 79 .flags = 0, \ 80 .cpu = 0, \ 81 .preempt_count = 1, \ 82 .addr_limit = KERNEL_DS, \ 83 .sp = 0, \ 84 .regs = NULL, \ 85} 86 87#define init_thread_info (init_thread_union.thread_info) 88#define init_stack (init_thread_union.stack) 89 90/* Tacky preprocessor trickery */ 91#define qqstr(s) qstr(s) 92#define qstr(s) #s 93#define QUOTED_THREADINFO_REG qqstr(THREADINFO_REG) 94 95register struct thread_info *__current_thread_info asm(QUOTED_THREADINFO_REG); 96#define current_thread_info() __current_thread_info 97 98#endif /* __ASSEMBLY__ */ 99 100/* 101 * thread information flags 102 * - these are process state flags that various assembly files 103 * may need to access 104 * - pending work-to-be-done flags are in LSW 105 * - other flags in MSW 106 */ 107 108#define TIF_SYSCALL_TRACE 0 /* syscall trace active */ 109#define TIF_NOTIFY_RESUME 1 /* resumption notification requested */ 110#define TIF_SIGPENDING 2 /* signal pending */ 111#define TIF_NEED_RESCHED 3 /* rescheduling necessary */ 112#define TIF_SINGLESTEP 4 /* restore ss @ return to usr mode */ 113#define TIF_RESTORE_SIGMASK 6 /* restore sig mask in do_signal() */ 114/* true if poll_idle() is polling TIF_NEED_RESCHED */ 115#define TIF_MEMDIE 17 /* OOM killer killed process */ 116 117#define _TIF_SYSCALL_TRACE (1 << TIF_SYSCALL_TRACE) 118#define _TIF_NOTIFY_RESUME (1 << TIF_NOTIFY_RESUME) 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/* work to do on interrupt/exception return - All but TIF_SYSCALL_TRACE */ 124#define _TIF_WORK_MASK (0x0000FFFF & ~_TIF_SYSCALL_TRACE) 125 126/* work to do on any return to u-space */ 127#define _TIF_ALLWORK_MASK 0x0000FFFF 128 129#endif /* __KERNEL__ */ 130 131#endif 132