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 	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 
32 /*
33  * Macros/functions for gaining access to the thread information structure.
34  */
35 #define INIT_THREAD_INFO(tsk)			\
36 {						\
37 	.task		= &tsk,			\
38 	.addr_limit	= KERNEL_DS,		\
39 	.preempt_count	= INIT_PREEMPT_COUNT,	\
40 }
41 
42 #define init_thread_info	(init_thread_union.thread_info)
43 #define init_stack		(init_thread_union.stack)
44 
45 /* How to get the thread information struct from C.  */
46 register struct thread_info *__current_thread_info __asm__("$8");
47 #define current_thread_info()  __current_thread_info
48 
49 #endif /* __ASSEMBLY__ */
50 
51 /* Thread information allocation.  */
52 #define THREAD_SIZE_ORDER 1
53 #define THREAD_SIZE (2*PAGE_SIZE)
54 
55 /*
56  * Thread information flags:
57  * - these are process state flags and used from assembly
58  * - pending work-to-be-done flags come first and must be assigned to be
59  *   within bits 0 to 7 to fit in and immediate operand.
60  *
61  * TIF_SYSCALL_TRACE is known to be 0 via blbs.
62  */
63 #define TIF_SYSCALL_TRACE	0	/* syscall trace active */
64 #define TIF_NOTIFY_RESUME	1	/* callback before returning to user */
65 #define TIF_SIGPENDING		2	/* signal pending */
66 #define TIF_NEED_RESCHED	3	/* rescheduling necessary */
67 #define TIF_SYSCALL_AUDIT	4	/* syscall audit active */
68 #define TIF_DIE_IF_KERNEL	9	/* dik recursion lock */
69 #define TIF_MEMDIE		13	/* is terminating due to OOM killer */
70 #define TIF_POLLING_NRFLAG	14	/* idle is polling for TIF_NEED_RESCHED */
71 
72 #define _TIF_SYSCALL_TRACE	(1<<TIF_SYSCALL_TRACE)
73 #define _TIF_SIGPENDING		(1<<TIF_SIGPENDING)
74 #define _TIF_NEED_RESCHED	(1<<TIF_NEED_RESCHED)
75 #define _TIF_NOTIFY_RESUME	(1<<TIF_NOTIFY_RESUME)
76 #define _TIF_SYSCALL_AUDIT	(1<<TIF_SYSCALL_AUDIT)
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)
82 
83 /* Work to do on any return to userspace.  */
84 #define _TIF_ALLWORK_MASK	(_TIF_WORK_MASK		\
85 				 | _TIF_SYSCALL_TRACE)
86 
87 #define TS_UAC_NOPRINT		0x0001	/* ! Preserve the following three */
88 #define TS_UAC_NOFIX		0x0002	/* ! flags as they match          */
89 #define TS_UAC_SIGBUS		0x0004	/* ! userspace part of 'osf_sysinfo' */
90 
91 #define SET_UNALIGN_CTL(task,value)	({				\
92 	__u32 status = task_thread_info(task)->status & ~UAC_BITMASK;	\
93 	if (value & PR_UNALIGN_NOPRINT)					\
94 		status |= TS_UAC_NOPRINT;				\
95 	if (value & PR_UNALIGN_SIGBUS)					\
96 		status |= TS_UAC_SIGBUS;				\
97 	if (value & 4)	/* alpha-specific */				\
98 		status |= TS_UAC_NOFIX;					\
99 	task_thread_info(task)->status = status;			\
100 	0; })
101 
102 #define GET_UNALIGN_CTL(task,value)	({				\
103 	__u32 status = task_thread_info(task)->status & ~UAC_BITMASK;	\
104 	__u32 res = 0;							\
105 	if (status & TS_UAC_NOPRINT)					\
106 		res |= PR_UNALIGN_NOPRINT;				\
107 	if (status & TS_UAC_SIGBUS)					\
108 		res |= PR_UNALIGN_SIGBUS;				\
109 	if (status & TS_UAC_NOFIX)					\
110 		res |= 4;						\
111 	put_user(res, (int __user *)(value));				\
112 	})
113 
114 #endif /* __KERNEL__ */
115 #endif /* _ALPHA_THREAD_INFO_H */
116