1 /*
2  * include/asm-xtensa/thread_info.h
3  *
4  * This file is subject to the terms and conditions of the GNU General Public
5  * License.  See the file "COPYING" in the main directory of this archive
6  * for more details.
7  *
8  * Copyright (C) 2001 - 2005 Tensilica Inc.
9  */
10 
11 #ifndef _XTENSA_THREAD_INFO_H
12 #define _XTENSA_THREAD_INFO_H
13 
14 #include <linux/stringify.h>
15 #include <asm/kmem_layout.h>
16 
17 #define CURRENT_SHIFT KERNEL_STACK_SHIFT
18 
19 #ifndef __ASSEMBLY__
20 # include <asm/processor.h>
21 #endif
22 
23 /*
24  * low level task data that entry.S needs immediate access to
25  * - this struct should fit entirely inside of one cache line
26  * - this struct shares the supervisor stack pages
27  * - if the contents of this structure are changed, the assembly constants
28  *   must also be changed
29  */
30 
31 #ifndef __ASSEMBLY__
32 
33 #if XTENSA_HAVE_COPROCESSORS
34 
35 typedef struct xtregs_coprocessor {
36 	xtregs_cp0_t cp0;
37 	xtregs_cp1_t cp1;
38 	xtregs_cp2_t cp2;
39 	xtregs_cp3_t cp3;
40 	xtregs_cp4_t cp4;
41 	xtregs_cp5_t cp5;
42 	xtregs_cp6_t cp6;
43 	xtregs_cp7_t cp7;
44 } xtregs_coprocessor_t;
45 
46 #endif
47 
48 struct thread_info {
49 	struct task_struct	*task;		/* main task structure */
50 	unsigned long		flags;		/* low level flags */
51 	unsigned long		status;		/* thread-synchronous flags */
52 	__u32			cpu;		/* current CPU */
53 	__s32			preempt_count;	/* 0 => preemptable,< 0 => BUG*/
54 
55 	mm_segment_t		addr_limit;	/* thread address space */
56 
57 	unsigned long		cpenable;
58 #if XCHAL_HAVE_EXCLUSIVE
59 	/* result of the most recent exclusive store */
60 	unsigned long		atomctl8;
61 #endif
62 
63 	/* Allocate storage for extra user states and coprocessor states. */
64 #if XTENSA_HAVE_COPROCESSORS
65 	xtregs_coprocessor_t	xtregs_cp;
66 #endif
67 	xtregs_user_t		xtregs_user;
68 };
69 
70 #endif
71 
72 /*
73  * macros/functions for gaining access to the thread information structure
74  */
75 
76 #ifndef __ASSEMBLY__
77 
78 #define INIT_THREAD_INFO(tsk)			\
79 {						\
80 	.task		= &tsk,			\
81 	.flags		= 0,			\
82 	.cpu		= 0,			\
83 	.preempt_count	= INIT_PREEMPT_COUNT,	\
84 	.addr_limit	= KERNEL_DS,		\
85 }
86 
87 /* how to get the thread information struct from C */
current_thread_info(void)88 static inline struct thread_info *current_thread_info(void)
89 {
90 	struct thread_info *ti;
91 	 __asm__("extui %0, a1, 0, "__stringify(CURRENT_SHIFT)"\n\t"
92 	         "xor %0, a1, %0" : "=&r" (ti) : );
93 	return ti;
94 }
95 
96 #else /* !__ASSEMBLY__ */
97 
98 /* how to get the thread information struct from ASM */
99 #define GET_THREAD_INFO(reg,sp) \
100 	extui reg, sp, 0, CURRENT_SHIFT; \
101 	xor   reg, sp, reg
102 #endif
103 
104 
105 /*
106  * thread information flags
107  * - these are process state flags that various assembly files may need to access
108  */
109 #define TIF_SYSCALL_TRACE	0	/* syscall trace active */
110 #define TIF_SIGPENDING		1	/* signal pending */
111 #define TIF_NEED_RESCHED	2	/* rescheduling necessary */
112 #define TIF_SINGLESTEP		3	/* restore singlestep on return to user mode */
113 #define TIF_SYSCALL_TRACEPOINT	4	/* syscall tracepoint instrumentation */
114 #define TIF_NOTIFY_SIGNAL	5	/* signal notifications exist */
115 #define TIF_RESTORE_SIGMASK	6	/* restore signal mask in do_signal() */
116 #define TIF_NOTIFY_RESUME	7	/* callback before returning to user */
117 #define TIF_DB_DISABLED		8	/* debug trap disabled for syscall */
118 #define TIF_SYSCALL_AUDIT	9	/* syscall auditing active */
119 #define TIF_SECCOMP		10	/* secure computing */
120 #define TIF_MEMDIE		11	/* is terminating due to OOM killer */
121 
122 #define _TIF_SYSCALL_TRACE	(1<<TIF_SYSCALL_TRACE)
123 #define _TIF_SIGPENDING		(1<<TIF_SIGPENDING)
124 #define _TIF_NEED_RESCHED	(1<<TIF_NEED_RESCHED)
125 #define _TIF_SINGLESTEP		(1<<TIF_SINGLESTEP)
126 #define _TIF_SYSCALL_TRACEPOINT	(1<<TIF_SYSCALL_TRACEPOINT)
127 #define _TIF_NOTIFY_SIGNAL	(1<<TIF_NOTIFY_SIGNAL)
128 #define _TIF_NOTIFY_RESUME	(1<<TIF_NOTIFY_RESUME)
129 #define _TIF_SYSCALL_AUDIT	(1<<TIF_SYSCALL_AUDIT)
130 #define _TIF_SECCOMP		(1<<TIF_SECCOMP)
131 
132 #define _TIF_WORK_MASK		(_TIF_SYSCALL_TRACE | _TIF_SINGLESTEP | \
133 				 _TIF_SYSCALL_TRACEPOINT | \
134 				 _TIF_SYSCALL_AUDIT | _TIF_SECCOMP)
135 
136 #define THREAD_SIZE KERNEL_STACK_SIZE
137 #define THREAD_SIZE_ORDER (KERNEL_STACK_SHIFT - PAGE_SHIFT)
138 
139 #endif	/* _XTENSA_THREAD_INFO */
140