1 /* thread_info.h: PowerPC low-level thread information
2  * adapted from the i386 version by Paul Mackerras
3  *
4  * Copyright (C) 2002  David Howells (dhowells@redhat.com)
5  * - Incorporating suggestions made by Linus Torvalds and Dave Miller
6  */
7 
8 #ifndef _ASM_POWERPC_THREAD_INFO_H
9 #define _ASM_POWERPC_THREAD_INFO_H
10 
11 #ifdef __KERNEL__
12 
13 /* We have 8k stacks on ppc32 and 16k on ppc64 */
14 
15 #if defined(CONFIG_PPC64)
16 #define THREAD_SHIFT		14
17 #elif defined(CONFIG_PPC_256K_PAGES)
18 #define THREAD_SHIFT		15
19 #else
20 #define THREAD_SHIFT		13
21 #endif
22 
23 #define THREAD_SIZE		(1 << THREAD_SHIFT)
24 
25 #ifdef CONFIG_PPC64
26 #define CURRENT_THREAD_INFO(dest, sp)	clrrdi dest, sp, THREAD_SHIFT
27 #else
28 #define CURRENT_THREAD_INFO(dest, sp)	rlwinm dest, sp, 0, 0, 31-THREAD_SHIFT
29 #endif
30 
31 #ifndef __ASSEMBLY__
32 #include <linux/cache.h>
33 #include <asm/processor.h>
34 #include <asm/page.h>
35 #include <linux/stringify.h>
36 
37 /*
38  * low level task data.
39  */
40 struct thread_info {
41 	struct task_struct *task;		/* main task structure */
42 	struct exec_domain *exec_domain;	/* execution domain */
43 	int		cpu;			/* cpu we're on */
44 	int		preempt_count;		/* 0 => preemptable,
45 						   <0 => BUG */
46 	struct restart_block restart_block;
47 	unsigned long	local_flags;		/* private flags for thread */
48 
49 	/* low level flags - has atomic operations done on it */
50 	unsigned long	flags ____cacheline_aligned_in_smp;
51 };
52 
53 /*
54  * macros/functions for gaining access to the thread information structure
55  */
56 #define INIT_THREAD_INFO(tsk)			\
57 {						\
58 	.task =		&tsk,			\
59 	.exec_domain =	&default_exec_domain,	\
60 	.cpu =		0,			\
61 	.preempt_count = INIT_PREEMPT_COUNT,	\
62 	.restart_block = {			\
63 		.fn = do_no_restart_syscall,	\
64 	},					\
65 	.flags =	0,			\
66 }
67 
68 #define init_thread_info	(init_thread_union.thread_info)
69 #define init_stack		(init_thread_union.stack)
70 
71 #define THREAD_SIZE_ORDER	(THREAD_SHIFT - PAGE_SHIFT)
72 
73 /* how to get the thread information struct from C */
74 static inline struct thread_info *current_thread_info(void)
75 {
76 	register unsigned long sp asm("r1");
77 
78 	/* gcc4, at least, is smart enough to turn this into a single
79 	 * rlwinm for ppc32 and clrrdi for ppc64 */
80 	return (struct thread_info *)(sp & ~(THREAD_SIZE-1));
81 }
82 
83 #endif /* __ASSEMBLY__ */
84 
85 #define PREEMPT_ACTIVE		0x10000000
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_POLLING_NRFLAG	3	/* true if poll_idle() is polling
94 					   TIF_NEED_RESCHED */
95 #define TIF_32BIT		4	/* 32 bit binary */
96 #define TIF_PERFMON_WORK	5	/* work for pfm_handle_work() */
97 #define TIF_PERFMON_CTXSW	6	/* perfmon needs ctxsw calls */
98 #define TIF_SYSCALL_AUDIT	7	/* syscall auditing active */
99 #define TIF_SINGLESTEP		8	/* singlestepping active */
100 #define TIF_MEMDIE		9	/* is terminating due to OOM killer */
101 #define TIF_SECCOMP		10	/* secure computing */
102 #define TIF_RESTOREALL		11	/* Restore all regs (implies NOERROR) */
103 #define TIF_NOERROR		12	/* Force successful syscall return */
104 #define TIF_NOTIFY_RESUME	13	/* callback before returning to user */
105 #define TIF_SYSCALL_TRACEPOINT	15	/* syscall tracepoint instrumentation */
106 
107 /* as above, but as bit values */
108 #define _TIF_SYSCALL_TRACE	(1<<TIF_SYSCALL_TRACE)
109 #define _TIF_SIGPENDING		(1<<TIF_SIGPENDING)
110 #define _TIF_NEED_RESCHED	(1<<TIF_NEED_RESCHED)
111 #define _TIF_POLLING_NRFLAG	(1<<TIF_POLLING_NRFLAG)
112 #define _TIF_32BIT		(1<<TIF_32BIT)
113 #define _TIF_PERFMON_WORK	(1<<TIF_PERFMON_WORK)
114 #define _TIF_PERFMON_CTXSW	(1<<TIF_PERFMON_CTXSW)
115 #define _TIF_SYSCALL_AUDIT	(1<<TIF_SYSCALL_AUDIT)
116 #define _TIF_SINGLESTEP		(1<<TIF_SINGLESTEP)
117 #define _TIF_SECCOMP		(1<<TIF_SECCOMP)
118 #define _TIF_RESTOREALL		(1<<TIF_RESTOREALL)
119 #define _TIF_NOERROR		(1<<TIF_NOERROR)
120 #define _TIF_NOTIFY_RESUME	(1<<TIF_NOTIFY_RESUME)
121 #define _TIF_SYSCALL_TRACEPOINT	(1<<TIF_SYSCALL_TRACEPOINT)
122 #define _TIF_SYSCALL_T_OR_A	(_TIF_SYSCALL_TRACE | _TIF_SYSCALL_AUDIT | \
123 				 _TIF_SECCOMP | _TIF_SYSCALL_TRACEPOINT)
124 
125 #define _TIF_USER_WORK_MASK	(_TIF_SIGPENDING | _TIF_NEED_RESCHED | \
126 				 _TIF_NOTIFY_RESUME)
127 #define _TIF_PERSYSCALL_MASK	(_TIF_RESTOREALL|_TIF_NOERROR)
128 
129 /* Bits in local_flags */
130 /* Don't move TLF_NAPPING without adjusting the code in entry_32.S */
131 #define TLF_NAPPING		0	/* idle thread enabled NAP mode */
132 #define TLF_SLEEPING		1	/* suspend code enabled SLEEP mode */
133 #define TLF_RESTORE_SIGMASK	2	/* Restore signal mask in do_signal */
134 #define TLF_LAZY_MMU		3	/* tlb_batch is active */
135 #define TLF_RUNLATCH		4	/* Is the runlatch enabled? */
136 
137 #define _TLF_NAPPING		(1 << TLF_NAPPING)
138 #define _TLF_SLEEPING		(1 << TLF_SLEEPING)
139 #define _TLF_RESTORE_SIGMASK	(1 << TLF_RESTORE_SIGMASK)
140 #define _TLF_LAZY_MMU		(1 << TLF_LAZY_MMU)
141 #define _TLF_RUNLATCH		(1 << TLF_RUNLATCH)
142 
143 #ifndef __ASSEMBLY__
144 #define HAVE_SET_RESTORE_SIGMASK	1
145 static inline void set_restore_sigmask(void)
146 {
147 	struct thread_info *ti = current_thread_info();
148 	ti->local_flags |= _TLF_RESTORE_SIGMASK;
149 	WARN_ON(!test_bit(TIF_SIGPENDING, &ti->flags));
150 }
151 static inline void clear_restore_sigmask(void)
152 {
153 	current_thread_info()->local_flags &= ~_TLF_RESTORE_SIGMASK;
154 }
155 static inline bool test_restore_sigmask(void)
156 {
157 	return current_thread_info()->local_flags & _TLF_RESTORE_SIGMASK;
158 }
159 static inline bool test_and_clear_restore_sigmask(void)
160 {
161 	struct thread_info *ti = current_thread_info();
162 	if (!(ti->local_flags & _TLF_RESTORE_SIGMASK))
163 		return false;
164 	ti->local_flags &= ~_TLF_RESTORE_SIGMASK;
165 	return true;
166 }
167 
168 static inline bool test_thread_local_flags(unsigned int flags)
169 {
170 	struct thread_info *ti = current_thread_info();
171 	return (ti->local_flags & flags) != 0;
172 }
173 
174 #ifdef CONFIG_PPC64
175 #define is_32bit_task()	(test_thread_flag(TIF_32BIT))
176 #else
177 #define is_32bit_task()	(1)
178 #endif
179 
180 #endif	/* !__ASSEMBLY__ */
181 
182 #endif /* __KERNEL__ */
183 
184 #endif /* _ASM_POWERPC_THREAD_INFO_H */
185