1 /*
2 * Copyright 2004-2010 Analog Devices Inc.
3 *
4 * Licensed under the GPL-2 or later.
5 */
6
7 #ifndef _ASM_THREAD_INFO_H
8 #define _ASM_THREAD_INFO_H
9
10 #include <asm/page.h>
11 #include <asm/entry.h>
12 #include <asm/l1layout.h>
13 #include <linux/compiler.h>
14
15 #ifdef __KERNEL__
16
17 /* Thread Align Mask to reach to the top of the stack
18 * for any process
19 */
20 #define ALIGN_PAGE_MASK 0xffffe000
21
22 /*
23 * Size of kernel stack for each process. This must be a power of 2...
24 */
25 #define THREAD_SIZE_ORDER 1
26 #define THREAD_SIZE 8192 /* 2 pages */
27 #define STACK_WARN (THREAD_SIZE/8)
28
29 #ifndef __ASSEMBLY__
30
31 typedef unsigned long mm_segment_t;
32
33 /*
34 * low level task data.
35 * If you change this, change the TI_* offsets below to match.
36 */
37
38 struct thread_info {
39 struct task_struct *task; /* main task structure */
40 struct exec_domain *exec_domain; /* execution domain */
41 unsigned long flags; /* low level flags */
42 int cpu; /* cpu we're on */
43 int preempt_count; /* 0 => preemptable, <0 => BUG */
44 mm_segment_t addr_limit; /* address limit */
45 #ifndef CONFIG_SMP
46 struct l1_scratch_task_info l1_task_info;
47 #endif
48 };
49
50 /*
51 * macros/functions for gaining access to the thread information structure
52 */
53 #define INIT_THREAD_INFO(tsk) \
54 { \
55 .task = &tsk, \
56 .exec_domain = &default_exec_domain, \
57 .flags = 0, \
58 .cpu = 0, \
59 .preempt_count = INIT_PREEMPT_COUNT, \
60 }
61 #define init_thread_info (init_thread_union.thread_info)
62 #define init_stack (init_thread_union.stack)
63
64 /* Given a task stack pointer, you can find its corresponding
65 * thread_info structure just by masking it to the THREAD_SIZE
66 * boundary (currently 8K as you can see above).
67 */
68 __attribute_const__
current_thread_info(void)69 static inline struct thread_info *current_thread_info(void)
70 {
71 struct thread_info *ti;
72 __asm__("%0 = sp;" : "=da"(ti));
73 return (struct thread_info *)((long)ti & ~((long)THREAD_SIZE-1));
74 }
75
76 #endif /* __ASSEMBLY__ */
77
78 /*
79 * Offsets in thread_info structure, used in assembly code
80 */
81 #define TI_TASK 0
82 #define TI_EXECDOMAIN 4
83 #define TI_FLAGS 8
84 #define TI_CPU 12
85 #define TI_PREEMPT 16
86
87 /*
88 * thread information flag bit numbers
89 */
90 #define TIF_SYSCALL_TRACE 0 /* syscall trace active */
91 #define TIF_SIGPENDING 1 /* signal pending */
92 #define TIF_NEED_RESCHED 2 /* rescheduling necessary */
93 #define TIF_MEMDIE 4 /* is terminating due to OOM killer */
94 #define TIF_RESTORE_SIGMASK 5 /* restore signal mask in do_signal() */
95 #define TIF_IRQ_SYNC 7 /* sync pipeline stage */
96 #define TIF_NOTIFY_RESUME 8 /* callback before returning to user */
97 #define TIF_SINGLESTEP 9
98
99 /* as above, but as bit values */
100 #define _TIF_SYSCALL_TRACE (1<<TIF_SYSCALL_TRACE)
101 #define _TIF_SIGPENDING (1<<TIF_SIGPENDING)
102 #define _TIF_NEED_RESCHED (1<<TIF_NEED_RESCHED)
103 #define _TIF_IRQ_SYNC (1<<TIF_IRQ_SYNC)
104 #define _TIF_NOTIFY_RESUME (1<<TIF_NOTIFY_RESUME)
105 #define _TIF_SINGLESTEP (1<<TIF_SINGLESTEP)
106
107 #define _TIF_WORK_MASK 0x0000FFFE /* work to do on interrupt/exception return */
108
109 #endif /* __KERNEL__ */
110
111 #endif /* _ASM_THREAD_INFO_H */
112