1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _ALPHA_THREAD_INFO_H
3 #define _ALPHA_THREAD_INFO_H
4 
5 #ifdef __KERNEL__
6 
7 #ifndef __ASSEMBLY__
8 #include <asm/processor.h>
9 #include <asm/types.h>
10 #include <asm/hwrpb.h>
11 #include <asm/sysinfo.h>
12 #endif
13 
14 #ifndef __ASSEMBLY__
15 struct thread_info {
16 	struct pcb_struct	pcb;		/* palcode state */
17 
18 	struct task_struct	*task;		/* main task structure */
19 	unsigned int		flags;		/* low level flags */
20 	unsigned int		ieee_state;	/* see fpu.h */
21 
22 	unsigned		cpu;		/* current CPU */
23 	int			preempt_count; /* 0 => preemptable, <0 => BUG */
24 	unsigned int		status;		/* thread-synchronous flags */
25 
26 	int bpt_nsaved;
27 	unsigned long bpt_addr[2];		/* breakpoint handling  */
28 	unsigned int bpt_insn[2];
29 	unsigned long fp[32];
30 };
31 
32 /*
33  * Macros/functions for gaining access to the thread information structure.
34  */
35 #define INIT_THREAD_INFO(tsk)			\
36 {						\
37 	.task		= &tsk,			\
38 	.preempt_count	= INIT_PREEMPT_COUNT,	\
39 }
40 
41 /* How to get the thread information struct from C.  */
42 register struct thread_info *__current_thread_info __asm__("$8");
43 #define current_thread_info()  __current_thread_info
44 
45 register unsigned long *current_stack_pointer __asm__ ("$30");
46 
47 #endif /* __ASSEMBLY__ */
48 
49 /* Thread information allocation.  */
50 #define THREAD_SIZE_ORDER 1
51 #define THREAD_SIZE (2*PAGE_SIZE)
52 
53 /*
54  * Thread information flags:
55  * - these are process state flags and used from assembly
56  * - pending work-to-be-done flags come first and must be assigned to be
57  *   within bits 0 to 7 to fit in and immediate operand.
58  *
59  * TIF_SYSCALL_TRACE is known to be 0 via blbs.
60  */
61 #define TIF_SYSCALL_TRACE	0	/* syscall trace active */
62 #define TIF_NOTIFY_RESUME	1	/* callback before returning to user */
63 #define TIF_SIGPENDING		2	/* signal pending */
64 #define TIF_NEED_RESCHED	3	/* rescheduling necessary */
65 #define TIF_SYSCALL_AUDIT	4	/* syscall audit active */
66 #define TIF_NOTIFY_SIGNAL	5	/* signal notifications exist */
67 #define TIF_DIE_IF_KERNEL	9	/* dik recursion lock */
68 #define TIF_MEMDIE		13	/* is terminating due to OOM killer */
69 #define TIF_POLLING_NRFLAG	14	/* idle is polling for TIF_NEED_RESCHED */
70 
71 #define _TIF_SYSCALL_TRACE	(1<<TIF_SYSCALL_TRACE)
72 #define _TIF_SIGPENDING		(1<<TIF_SIGPENDING)
73 #define _TIF_NEED_RESCHED	(1<<TIF_NEED_RESCHED)
74 #define _TIF_NOTIFY_RESUME	(1<<TIF_NOTIFY_RESUME)
75 #define _TIF_SYSCALL_AUDIT	(1<<TIF_SYSCALL_AUDIT)
76 #define _TIF_NOTIFY_SIGNAL	(1<<TIF_NOTIFY_SIGNAL)
77 #define _TIF_POLLING_NRFLAG	(1<<TIF_POLLING_NRFLAG)
78 
79 /* Work to do on interrupt/exception return.  */
80 #define _TIF_WORK_MASK		(_TIF_SIGPENDING | _TIF_NEED_RESCHED | \
81 				 _TIF_NOTIFY_RESUME | _TIF_NOTIFY_SIGNAL)
82 
83 #define TS_UAC_NOPRINT		0x0001	/* ! Preserve the following three */
84 #define TS_UAC_NOFIX		0x0002	/* ! flags as they match          */
85 #define TS_UAC_SIGBUS		0x0004	/* ! userspace part of 'osf_sysinfo' */
86 
87 #define TS_SAVED_FP		0x0008
88 #define TS_RESTORE_FP		0x0010
89 
90 #define SET_UNALIGN_CTL(task,value)	({				\
91 	__u32 status = task_thread_info(task)->status & ~UAC_BITMASK;	\
92 	if (value & PR_UNALIGN_NOPRINT)					\
93 		status |= TS_UAC_NOPRINT;				\
94 	if (value & PR_UNALIGN_SIGBUS)					\
95 		status |= TS_UAC_SIGBUS;				\
96 	if (value & 4)	/* alpha-specific */				\
97 		status |= TS_UAC_NOFIX;					\
98 	task_thread_info(task)->status = status;			\
99 	0; })
100 
101 #define GET_UNALIGN_CTL(task,value)	({				\
102 	__u32 status = task_thread_info(task)->status & ~UAC_BITMASK;	\
103 	__u32 res = 0;							\
104 	if (status & TS_UAC_NOPRINT)					\
105 		res |= PR_UNALIGN_NOPRINT;				\
106 	if (status & TS_UAC_SIGBUS)					\
107 		res |= PR_UNALIGN_SIGBUS;				\
108 	if (status & TS_UAC_NOFIX)					\
109 		res |= 4;						\
110 	put_user(res, (int __user *)(value));				\
111 	})
112 
113 #ifndef __ASSEMBLY__
114 extern void __save_fpu(void);
115 
116 static inline void save_fpu(void)
117 {
118 	if (!(current_thread_info()->status & TS_SAVED_FP)) {
119 		current_thread_info()->status |= TS_SAVED_FP;
120 		__save_fpu();
121 	}
122 }
123 #endif
124 
125 #endif /* __KERNEL__ */
126 #endif /* _ALPHA_THREAD_INFO_H */
127