Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
tjh.dev
kernel
os
linux
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