1 /* thread_info.h: MIPS 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_THREAD_INFO_H
8 #define _ASM_THREAD_INFO_H
9 
10 #ifdef __KERNEL__
11 
12 
13 #ifndef __ASSEMBLY__
14 
15 #include <asm/processor.h>
16 
17 /*
18  * low level task data that entry.S needs immediate access to
19  * - this struct should fit entirely inside of one cache line
20  * - this struct shares the supervisor stack pages
21  * - if the contents of this structure are changed, the assembly constants
22  *   must also be changed
23  */
24 struct thread_info {
25 	struct task_struct	*task;		/* main task structure */
26 	struct exec_domain	*exec_domain;	/* execution domain */
27 	unsigned long		flags;		/* low level flags */
28 	unsigned long		tp_value;	/* thread pointer */
29 	__u32			cpu;		/* current CPU */
30 	int			preempt_count;	/* 0 => preemptable, <0 => BUG */
31 
32 	mm_segment_t		addr_limit;	/* thread address space:
33 						   0-0xBFFFFFFF for user-thead
34 						   0-0xFFFFFFFF for kernel-thread
35 						*/
36 	struct restart_block	restart_block;
37 	struct pt_regs		*regs;
38 };
39 
40 /*
41  * macros/functions for gaining access to the thread information structure
42  */
43 #define INIT_THREAD_INFO(tsk)			\
44 {						\
45 	.task		= &tsk,			\
46 	.exec_domain	= &default_exec_domain,	\
47 	.flags		= _TIF_FIXADE,		\
48 	.cpu		= 0,			\
49 	.preempt_count	= INIT_PREEMPT_COUNT,	\
50 	.addr_limit	= KERNEL_DS,		\
51 	.restart_block	= {			\
52 		.fn = do_no_restart_syscall,	\
53 	},					\
54 }
55 
56 #define init_thread_info	(init_thread_union.thread_info)
57 #define init_stack		(init_thread_union.stack)
58 
59 /* How to get the thread information struct from C.  */
60 register struct thread_info *__current_thread_info __asm__("$28");
61 #define current_thread_info()  __current_thread_info
62 
63 /* thread information allocation */
64 #if defined(CONFIG_PAGE_SIZE_4KB) && defined(CONFIG_32BIT)
65 #define THREAD_SIZE_ORDER (1)
66 #endif
67 #if defined(CONFIG_PAGE_SIZE_4KB) && defined(CONFIG_64BIT)
68 #define THREAD_SIZE_ORDER (2)
69 #endif
70 #ifdef CONFIG_PAGE_SIZE_8KB
71 #define THREAD_SIZE_ORDER (1)
72 #endif
73 #ifdef CONFIG_PAGE_SIZE_16KB
74 #define THREAD_SIZE_ORDER (0)
75 #endif
76 #ifdef CONFIG_PAGE_SIZE_32KB
77 #define THREAD_SIZE_ORDER (0)
78 #endif
79 #ifdef CONFIG_PAGE_SIZE_64KB
80 #define THREAD_SIZE_ORDER (0)
81 #endif
82 
83 #define THREAD_SIZE (PAGE_SIZE << THREAD_SIZE_ORDER)
84 #define THREAD_MASK (THREAD_SIZE - 1UL)
85 
86 #define STACK_WARN	(THREAD_SIZE / 8)
87 
88 #define __HAVE_ARCH_THREAD_INFO_ALLOCATOR
89 
90 #ifdef CONFIG_DEBUG_STACK_USAGE
91 #define alloc_thread_info_node(tsk, node) \
92 		kzalloc_node(THREAD_SIZE, GFP_KERNEL, node)
93 #else
94 #define alloc_thread_info_node(tsk, node) \
95 		kmalloc_node(THREAD_SIZE, GFP_KERNEL, node)
96 #endif
97 
98 #define free_thread_info(info) kfree(info)
99 
100 #endif /* !__ASSEMBLY__ */
101 
102 #define PREEMPT_ACTIVE		0x10000000
103 
104 /*
105  * thread information flags
106  * - these are process state flags that various assembly files may need to
107  *   access
108  * - pending work-to-be-done flags are in LSW
109  * - other flags in MSW
110  */
111 #define TIF_SIGPENDING		1	/* signal pending */
112 #define TIF_NEED_RESCHED	2	/* rescheduling necessary */
113 #define TIF_SYSCALL_AUDIT	3	/* syscall auditing active */
114 #define TIF_SECCOMP		4	/* secure computing */
115 #define TIF_NOTIFY_RESUME	5	/* callback before returning to user */
116 #define TIF_RESTORE_SIGMASK	9	/* restore signal mask in do_signal() */
117 #define TIF_USEDFPU		16	/* FPU was used by this task this quantum (SMP) */
118 #define TIF_POLLING_NRFLAG	17	/* true if poll_idle() is polling TIF_NEED_RESCHED */
119 #define TIF_MEMDIE		18	/* is terminating due to OOM killer */
120 #define TIF_FREEZE		19
121 #define TIF_FIXADE		20	/* Fix address errors in software */
122 #define TIF_LOGADE		21	/* Log address errors to syslog */
123 #define TIF_32BIT_REGS		22	/* also implies 16/32 fprs */
124 #define TIF_32BIT_ADDR		23	/* 32-bit address space (o32/n32) */
125 #define TIF_FPUBOUND		24	/* thread bound to FPU-full CPU set */
126 #define TIF_LOAD_WATCH		25	/* If set, load watch registers */
127 #define TIF_SYSCALL_TRACE	31	/* syscall trace active */
128 
129 #ifdef CONFIG_MIPS32_O32
130 #define TIF_32BIT TIF_32BIT_REGS
131 #elif defined(CONFIG_MIPS32_N32)
132 #define TIF_32BIT _TIF_32BIT_ADDR
133 #endif /* CONFIG_MIPS32_O32 */
134 
135 #define _TIF_SYSCALL_TRACE	(1<<TIF_SYSCALL_TRACE)
136 #define _TIF_SIGPENDING		(1<<TIF_SIGPENDING)
137 #define _TIF_NEED_RESCHED	(1<<TIF_NEED_RESCHED)
138 #define _TIF_SYSCALL_AUDIT	(1<<TIF_SYSCALL_AUDIT)
139 #define _TIF_SECCOMP		(1<<TIF_SECCOMP)
140 #define _TIF_NOTIFY_RESUME	(1<<TIF_NOTIFY_RESUME)
141 #define _TIF_RESTORE_SIGMASK	(1<<TIF_RESTORE_SIGMASK)
142 #define _TIF_USEDFPU		(1<<TIF_USEDFPU)
143 #define _TIF_POLLING_NRFLAG	(1<<TIF_POLLING_NRFLAG)
144 #define _TIF_FREEZE		(1<<TIF_FREEZE)
145 #define _TIF_FIXADE		(1<<TIF_FIXADE)
146 #define _TIF_LOGADE		(1<<TIF_LOGADE)
147 #define _TIF_32BIT_REGS		(1<<TIF_32BIT_REGS)
148 #define _TIF_32BIT_ADDR		(1<<TIF_32BIT_ADDR)
149 #define _TIF_FPUBOUND		(1<<TIF_FPUBOUND)
150 #define _TIF_LOAD_WATCH		(1<<TIF_LOAD_WATCH)
151 
152 /* work to do on interrupt/exception return */
153 #define _TIF_WORK_MASK		(0x0000ffef &				\
154 					~(_TIF_SECCOMP | _TIF_SYSCALL_AUDIT))
155 /* work to do on any return to u-space */
156 #define _TIF_ALLWORK_MASK	(0x8000ffff & ~_TIF_SECCOMP)
157 
158 #endif /* __KERNEL__ */
159 
160 #endif /* _ASM_THREAD_INFO_H */
161