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)	stringify_in_c(clrrdi dest, sp, THREAD_SHIFT)
27 #else
28 #define CURRENT_THREAD_INFO(dest, sp)	stringify_in_c(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 	int		cpu;			/* cpu we're on */
43 	int		preempt_count;		/* 0 => preemptable,
44 						   <0 => BUG */
45 	unsigned long	local_flags;		/* private flags for thread */
46 
47 	/* low level flags - has atomic operations done on it */
48 	unsigned long	flags ____cacheline_aligned_in_smp;
49 };
50 
51 /*
52  * macros/functions for gaining access to the thread information structure
53  */
54 #define INIT_THREAD_INFO(tsk)			\
55 {						\
56 	.task =		&tsk,			\
57 	.cpu =		0,			\
58 	.preempt_count = INIT_PREEMPT_COUNT,	\
59 	.flags =	0,			\
60 }
61 
62 #define init_thread_info	(init_thread_union.thread_info)
63 #define init_stack		(init_thread_union.stack)
64 
65 #define THREAD_SIZE_ORDER	(THREAD_SHIFT - PAGE_SHIFT)
66 
67 /* how to get the thread information struct from C */
68 static inline struct thread_info *current_thread_info(void)
69 {
70 	unsigned long val;
71 
72 	asm (CURRENT_THREAD_INFO(%0,1) : "=r" (val));
73 
74 	return (struct thread_info *)val;
75 }
76 
77 #endif /* __ASSEMBLY__ */
78 
79 /*
80  * thread information flag bit numbers
81  */
82 #define TIF_SYSCALL_TRACE	0	/* syscall trace active */
83 #define TIF_SIGPENDING		1	/* signal pending */
84 #define TIF_NEED_RESCHED	2	/* rescheduling necessary */
85 #define TIF_POLLING_NRFLAG	3	/* true if poll_idle() is polling
86 					   TIF_NEED_RESCHED */
87 #define TIF_32BIT		4	/* 32 bit binary */
88 #define TIF_RESTORE_TM		5	/* need to restore TM FP/VEC/VSX */
89 #define TIF_SYSCALL_AUDIT	7	/* syscall auditing active */
90 #define TIF_SINGLESTEP		8	/* singlestepping active */
91 #define TIF_NOHZ		9	/* in adaptive nohz mode */
92 #define TIF_SECCOMP		10	/* secure computing */
93 #define TIF_RESTOREALL		11	/* Restore all regs (implies NOERROR) */
94 #define TIF_NOERROR		12	/* Force successful syscall return */
95 #define TIF_NOTIFY_RESUME	13	/* callback before returning to user */
96 #define TIF_UPROBE		14	/* breakpointed or single-stepping */
97 #define TIF_SYSCALL_TRACEPOINT	15	/* syscall tracepoint instrumentation */
98 #define TIF_EMULATE_STACK_STORE	16	/* Is an instruction emulation
99 						for stack store? */
100 #define TIF_MEMDIE		17	/* is terminating due to OOM killer */
101 #if defined(CONFIG_PPC64)
102 #define TIF_ELF2ABI		18	/* function descriptors must die! */
103 #endif
104 
105 /* as above, but as bit values */
106 #define _TIF_SYSCALL_TRACE	(1<<TIF_SYSCALL_TRACE)
107 #define _TIF_SIGPENDING		(1<<TIF_SIGPENDING)
108 #define _TIF_NEED_RESCHED	(1<<TIF_NEED_RESCHED)
109 #define _TIF_POLLING_NRFLAG	(1<<TIF_POLLING_NRFLAG)
110 #define _TIF_32BIT		(1<<TIF_32BIT)
111 #define _TIF_RESTORE_TM		(1<<TIF_RESTORE_TM)
112 #define _TIF_SYSCALL_AUDIT	(1<<TIF_SYSCALL_AUDIT)
113 #define _TIF_SINGLESTEP		(1<<TIF_SINGLESTEP)
114 #define _TIF_SECCOMP		(1<<TIF_SECCOMP)
115 #define _TIF_RESTOREALL		(1<<TIF_RESTOREALL)
116 #define _TIF_NOERROR		(1<<TIF_NOERROR)
117 #define _TIF_NOTIFY_RESUME	(1<<TIF_NOTIFY_RESUME)
118 #define _TIF_UPROBE		(1<<TIF_UPROBE)
119 #define _TIF_SYSCALL_TRACEPOINT	(1<<TIF_SYSCALL_TRACEPOINT)
120 #define _TIF_EMULATE_STACK_STORE	(1<<TIF_EMULATE_STACK_STORE)
121 #define _TIF_NOHZ		(1<<TIF_NOHZ)
122 #define _TIF_SYSCALL_DOTRACE	(_TIF_SYSCALL_TRACE | _TIF_SYSCALL_AUDIT | \
123 				 _TIF_SECCOMP | _TIF_SYSCALL_TRACEPOINT | \
124 				 _TIF_NOHZ)
125 
126 #define _TIF_USER_WORK_MASK	(_TIF_SIGPENDING | _TIF_NEED_RESCHED | \
127 				 _TIF_NOTIFY_RESUME | _TIF_UPROBE | \
128 				 _TIF_RESTORE_TM)
129 #define _TIF_PERSYSCALL_MASK	(_TIF_RESTOREALL|_TIF_NOERROR)
130 
131 /* Bits in local_flags */
132 /* Don't move TLF_NAPPING without adjusting the code in entry_32.S */
133 #define TLF_NAPPING		0	/* idle thread enabled NAP mode */
134 #define TLF_SLEEPING		1	/* suspend code enabled SLEEP mode */
135 #define TLF_RESTORE_SIGMASK	2	/* Restore signal mask in do_signal */
136 #define TLF_LAZY_MMU		3	/* tlb_batch is active */
137 #define TLF_RUNLATCH		4	/* Is the runlatch enabled? */
138 
139 #define _TLF_NAPPING		(1 << TLF_NAPPING)
140 #define _TLF_SLEEPING		(1 << TLF_SLEEPING)
141 #define _TLF_RESTORE_SIGMASK	(1 << TLF_RESTORE_SIGMASK)
142 #define _TLF_LAZY_MMU		(1 << TLF_LAZY_MMU)
143 #define _TLF_RUNLATCH		(1 << TLF_RUNLATCH)
144 
145 #ifndef __ASSEMBLY__
146 #define HAVE_SET_RESTORE_SIGMASK	1
147 static inline void set_restore_sigmask(void)
148 {
149 	struct thread_info *ti = current_thread_info();
150 	ti->local_flags |= _TLF_RESTORE_SIGMASK;
151 	WARN_ON(!test_bit(TIF_SIGPENDING, &ti->flags));
152 }
153 static inline void clear_restore_sigmask(void)
154 {
155 	current_thread_info()->local_flags &= ~_TLF_RESTORE_SIGMASK;
156 }
157 static inline bool test_restore_sigmask(void)
158 {
159 	return current_thread_info()->local_flags & _TLF_RESTORE_SIGMASK;
160 }
161 static inline bool test_and_clear_restore_sigmask(void)
162 {
163 	struct thread_info *ti = current_thread_info();
164 	if (!(ti->local_flags & _TLF_RESTORE_SIGMASK))
165 		return false;
166 	ti->local_flags &= ~_TLF_RESTORE_SIGMASK;
167 	return true;
168 }
169 
170 static inline bool test_thread_local_flags(unsigned int flags)
171 {
172 	struct thread_info *ti = current_thread_info();
173 	return (ti->local_flags & flags) != 0;
174 }
175 
176 #ifdef CONFIG_PPC64
177 #define is_32bit_task()	(test_thread_flag(TIF_32BIT))
178 #else
179 #define is_32bit_task()	(1)
180 #endif
181 
182 #if defined(CONFIG_PPC64)
183 #define is_elf2_task() (test_thread_flag(TIF_ELF2ABI))
184 #else
185 #define is_elf2_task() (0)
186 #endif
187 
188 #endif	/* !__ASSEMBLY__ */
189 
190 #endif /* __KERNEL__ */
191 
192 #endif /* _ASM_POWERPC_THREAD_INFO_H */
193