1 #ifndef _ALPHA_THREAD_INFO_H
2 #define _ALPHA_THREAD_INFO_H
3 
4 #ifdef __KERNEL__
5 
6 #ifndef __ASSEMBLY__
7 #include <asm/processor.h>
8 #include <asm/types.h>
9 #include <asm/hwrpb.h>
10 #include <asm/sysinfo.h>
11 #endif
12 
13 #ifndef __ASSEMBLY__
14 struct thread_info {
15 	struct pcb_struct	pcb;		/* palcode state */
16 
17 	struct task_struct	*task;		/* main task structure */
18 	unsigned int		flags;		/* low level flags */
19 	unsigned int		ieee_state;	/* see fpu.h */
20 
21 	struct exec_domain	*exec_domain;	/* execution domain */
22 	mm_segment_t		addr_limit;	/* thread address space */
23 	unsigned		cpu;		/* current CPU */
24 	int			preempt_count; /* 0 => preemptable, <0 => BUG */
25 	unsigned int		status;		/* thread-synchronous flags */
26 
27 	int bpt_nsaved;
28 	unsigned long bpt_addr[2];		/* breakpoint handling  */
29 	unsigned int bpt_insn[2];
30 
31 	struct restart_block	restart_block;
32 };
33 
34 /*
35  * Macros/functions for gaining access to the thread information structure.
36  */
37 #define INIT_THREAD_INFO(tsk)			\
38 {						\
39 	.task		= &tsk,			\
40 	.exec_domain	= &default_exec_domain,	\
41 	.addr_limit	= KERNEL_DS,		\
42 	.preempt_count	= INIT_PREEMPT_COUNT,	\
43 	.restart_block = {			\
44 		.fn = do_no_restart_syscall,	\
45 	},					\
46 }
47 
48 #define init_thread_info	(init_thread_union.thread_info)
49 #define init_stack		(init_thread_union.stack)
50 
51 /* How to get the thread information struct from C.  */
52 register struct thread_info *__current_thread_info __asm__("$8");
53 #define current_thread_info()  __current_thread_info
54 
55 #endif /* __ASSEMBLY__ */
56 
57 /* Thread information allocation.  */
58 #define THREAD_SIZE_ORDER 1
59 #define THREAD_SIZE (2*PAGE_SIZE)
60 
61 #define PREEMPT_ACTIVE		0x40000000
62 
63 /*
64  * Thread information flags:
65  * - these are process state flags and used from assembly
66  * - pending work-to-be-done flags come first and must be assigned to be
67  *   within bits 0 to 7 to fit in and immediate operand.
68  *
69  * TIF_SYSCALL_TRACE is known to be 0 via blbs.
70  */
71 #define TIF_SYSCALL_TRACE	0	/* syscall trace active */
72 #define TIF_NOTIFY_RESUME	1	/* callback before returning to user */
73 #define TIF_SIGPENDING		2	/* signal pending */
74 #define TIF_NEED_RESCHED	3	/* rescheduling necessary */
75 #define TIF_DIE_IF_KERNEL	9	/* dik recursion lock */
76 #define TIF_MEMDIE		13	/* is terminating due to OOM killer */
77 
78 #define _TIF_SYSCALL_TRACE	(1<<TIF_SYSCALL_TRACE)
79 #define _TIF_SIGPENDING		(1<<TIF_SIGPENDING)
80 #define _TIF_NEED_RESCHED	(1<<TIF_NEED_RESCHED)
81 #define _TIF_NOTIFY_RESUME	(1<<TIF_NOTIFY_RESUME)
82 
83 /* Work to do on interrupt/exception return.  */
84 #define _TIF_WORK_MASK		(_TIF_SIGPENDING | _TIF_NEED_RESCHED | \
85 				 _TIF_NOTIFY_RESUME)
86 
87 /* Work to do on any return to userspace.  */
88 #define _TIF_ALLWORK_MASK	(_TIF_WORK_MASK		\
89 				 | _TIF_SYSCALL_TRACE)
90 
91 #define TS_UAC_NOPRINT		0x0001	/* ! Preserve the following three */
92 #define TS_UAC_NOFIX		0x0002	/* ! flags as they match          */
93 #define TS_UAC_SIGBUS		0x0004	/* ! userspace part of 'osf_sysinfo' */
94 #define TS_RESTORE_SIGMASK	0x0008	/* restore signal mask in do_signal() */
95 #define TS_POLLING		0x0010	/* idle task polling need_resched,
96 					   skip sending interrupt */
97 
98 #define tsk_is_polling(t) (task_thread_info(t)->status & TS_POLLING)
99 
100 #ifndef __ASSEMBLY__
101 #define HAVE_SET_RESTORE_SIGMASK	1
102 static inline void set_restore_sigmask(void)
103 {
104 	struct thread_info *ti = current_thread_info();
105 	ti->status |= TS_RESTORE_SIGMASK;
106 	WARN_ON(!test_bit(TIF_SIGPENDING, (unsigned long *)&ti->flags));
107 }
108 static inline void clear_restore_sigmask(void)
109 {
110 	current_thread_info()->status &= ~TS_RESTORE_SIGMASK;
111 }
112 static inline bool test_restore_sigmask(void)
113 {
114 	return current_thread_info()->status & TS_RESTORE_SIGMASK;
115 }
116 static inline bool test_and_clear_restore_sigmask(void)
117 {
118 	struct thread_info *ti = current_thread_info();
119 	if (!(ti->status & TS_RESTORE_SIGMASK))
120 		return false;
121 	ti->status &= ~TS_RESTORE_SIGMASK;
122 	return true;
123 }
124 #endif
125 
126 #define SET_UNALIGN_CTL(task,value)	({				\
127 	__u32 status = task_thread_info(task)->status & ~UAC_BITMASK;	\
128 	if (value & PR_UNALIGN_NOPRINT)					\
129 		status |= TS_UAC_NOPRINT;				\
130 	if (value & PR_UNALIGN_SIGBUS)					\
131 		status |= TS_UAC_SIGBUS;				\
132 	if (value & 4)	/* alpha-specific */				\
133 		status |= TS_UAC_NOFIX;					\
134 	task_thread_info(task)->status = status;			\
135 	0; })
136 
137 #define GET_UNALIGN_CTL(task,value)	({				\
138 	__u32 status = task_thread_info(task)->status & ~UAC_BITMASK;	\
139 	__u32 res = 0;							\
140 	if (status & TS_UAC_NOPRINT)					\
141 		res |= PR_UNALIGN_NOPRINT;				\
142 	if (status & TS_UAC_SIGBUS)					\
143 		res |= PR_UNALIGN_SIGBUS;				\
144 	if (status & TS_UAC_NOFIX)					\
145 		res |= 4;						\
146 	put_user(res, (int __user *)(value));				\
147 	})
148 
149 #endif /* __KERNEL__ */
150 #endif /* _ALPHA_THREAD_INFO_H */
151