1 /* thread_info.h: MIPS low-level thread information
2 *
3 * Copyright (C) 2002 David Howells (dhowells@redhat.com)
4 * - Incorporating suggestions made by Linus Torvalds and Dave Miller
5 */
6
7 #ifndef _ASM_THREAD_INFO_H
8 #define _ASM_THREAD_INFO_H
9
10 #ifdef __KERNEL__
11
12
13 #ifndef __ASSEMBLY__
14
15 #include <asm/processor.h>
16
17 /*
18 * low level task data that entry.S needs immediate access to
19 * - this struct should fit entirely inside of one cache line
20 * - this struct shares the supervisor stack pages
21 * - if the contents of this structure are changed, the assembly constants
22 * must also be changed
23 */
24 struct thread_info {
25 struct task_struct *task; /* main task structure */
26 struct exec_domain *exec_domain; /* execution domain */
27 unsigned long flags; /* low level flags */
28 unsigned long tp_value; /* thread pointer */
29 __u32 cpu; /* current CPU */
30 int preempt_count; /* 0 => preemptable, <0 => BUG */
31 int r2_emul_return; /* 1 => Returning from R2 emulator */
32 mm_segment_t addr_limit; /*
33 * thread address space limit:
34 * 0x7fffffff for user-thead
35 * 0xffffffff for kernel-thread
36 */
37 struct pt_regs *regs;
38 long syscall; /* syscall number */
39 };
40
41 /*
42 * macros/functions for gaining access to the thread information structure
43 */
44 #define INIT_THREAD_INFO(tsk) \
45 { \
46 .task = &tsk, \
47 .exec_domain = &default_exec_domain, \
48 .flags = _TIF_FIXADE, \
49 .cpu = 0, \
50 .preempt_count = INIT_PREEMPT_COUNT, \
51 .addr_limit = KERNEL_DS, \
52 }
53
54 #define init_thread_info (init_thread_union.thread_info)
55 #define init_stack (init_thread_union.stack)
56
57 /* How to get the thread information struct from C. */
58 register struct thread_info *__current_thread_info __asm__("$28");
59
current_thread_info(void)60 static inline struct thread_info *current_thread_info(void)
61 {
62 return __current_thread_info;
63 }
64
65 #endif /* !__ASSEMBLY__ */
66
67 /* thread information allocation */
68 #if defined(CONFIG_PAGE_SIZE_4KB) && defined(CONFIG_32BIT)
69 #define THREAD_SIZE_ORDER (1)
70 #endif
71 #if defined(CONFIG_PAGE_SIZE_4KB) && defined(CONFIG_64BIT)
72 #define THREAD_SIZE_ORDER (2)
73 #endif
74 #ifdef CONFIG_PAGE_SIZE_8KB
75 #define THREAD_SIZE_ORDER (1)
76 #endif
77 #ifdef CONFIG_PAGE_SIZE_16KB
78 #define THREAD_SIZE_ORDER (0)
79 #endif
80 #ifdef CONFIG_PAGE_SIZE_32KB
81 #define THREAD_SIZE_ORDER (0)
82 #endif
83 #ifdef CONFIG_PAGE_SIZE_64KB
84 #define THREAD_SIZE_ORDER (0)
85 #endif
86
87 #define THREAD_SIZE (PAGE_SIZE << THREAD_SIZE_ORDER)
88 #define THREAD_MASK (THREAD_SIZE - 1UL)
89
90 #define STACK_WARN (THREAD_SIZE / 8)
91
92 /*
93 * thread information flags
94 * - these are process state flags that various assembly files may need to
95 * access
96 * - pending work-to-be-done flags are in LSW
97 * - other flags in MSW
98 */
99 #define TIF_SIGPENDING 1 /* signal pending */
100 #define TIF_NEED_RESCHED 2 /* rescheduling necessary */
101 #define TIF_SYSCALL_AUDIT 3 /* syscall auditing active */
102 #define TIF_SECCOMP 4 /* secure computing */
103 #define TIF_NOTIFY_RESUME 5 /* callback before returning to user */
104 #define TIF_RESTORE_SIGMASK 9 /* restore signal mask in do_signal() */
105 #define TIF_USEDFPU 16 /* FPU was used by this task this quantum (SMP) */
106 #define TIF_MEMDIE 18 /* is terminating due to OOM killer */
107 #define TIF_NOHZ 19 /* in adaptive nohz mode */
108 #define TIF_FIXADE 20 /* Fix address errors in software */
109 #define TIF_LOGADE 21 /* Log address errors to syslog */
110 #define TIF_32BIT_REGS 22 /* 32-bit general purpose registers */
111 #define TIF_32BIT_ADDR 23 /* 32-bit address space (o32/n32) */
112 #define TIF_FPUBOUND 24 /* thread bound to FPU-full CPU set */
113 #define TIF_LOAD_WATCH 25 /* If set, load watch registers */
114 #define TIF_SYSCALL_TRACEPOINT 26 /* syscall tracepoint instrumentation */
115 #define TIF_32BIT_FPREGS 27 /* 32-bit floating point registers */
116 #define TIF_HYBRID_FPREGS 28 /* 64b FP registers, odd singles in bits 63:32 of even doubles */
117 #define TIF_USEDMSA 29 /* MSA has been used this quantum */
118 #define TIF_MSA_CTX_LIVE 30 /* MSA context must be preserved */
119 #define TIF_SYSCALL_TRACE 31 /* syscall trace active */
120
121 #define _TIF_SYSCALL_TRACE (1<<TIF_SYSCALL_TRACE)
122 #define _TIF_SIGPENDING (1<<TIF_SIGPENDING)
123 #define _TIF_NEED_RESCHED (1<<TIF_NEED_RESCHED)
124 #define _TIF_SYSCALL_AUDIT (1<<TIF_SYSCALL_AUDIT)
125 #define _TIF_SECCOMP (1<<TIF_SECCOMP)
126 #define _TIF_NOTIFY_RESUME (1<<TIF_NOTIFY_RESUME)
127 #define _TIF_USEDFPU (1<<TIF_USEDFPU)
128 #define _TIF_NOHZ (1<<TIF_NOHZ)
129 #define _TIF_FIXADE (1<<TIF_FIXADE)
130 #define _TIF_LOGADE (1<<TIF_LOGADE)
131 #define _TIF_32BIT_REGS (1<<TIF_32BIT_REGS)
132 #define _TIF_32BIT_ADDR (1<<TIF_32BIT_ADDR)
133 #define _TIF_FPUBOUND (1<<TIF_FPUBOUND)
134 #define _TIF_LOAD_WATCH (1<<TIF_LOAD_WATCH)
135 #define _TIF_32BIT_FPREGS (1<<TIF_32BIT_FPREGS)
136 #define _TIF_HYBRID_FPREGS (1<<TIF_HYBRID_FPREGS)
137 #define _TIF_USEDMSA (1<<TIF_USEDMSA)
138 #define _TIF_MSA_CTX_LIVE (1<<TIF_MSA_CTX_LIVE)
139 #define _TIF_SYSCALL_TRACEPOINT (1<<TIF_SYSCALL_TRACEPOINT)
140
141 #define _TIF_WORK_SYSCALL_ENTRY (_TIF_NOHZ | _TIF_SYSCALL_TRACE | \
142 _TIF_SYSCALL_AUDIT | \
143 _TIF_SYSCALL_TRACEPOINT | _TIF_SECCOMP)
144
145 /* work to do in syscall_trace_leave() */
146 #define _TIF_WORK_SYSCALL_EXIT (_TIF_NOHZ | _TIF_SYSCALL_TRACE | \
147 _TIF_SYSCALL_AUDIT | _TIF_SYSCALL_TRACEPOINT)
148
149 /* work to do on interrupt/exception return */
150 #define _TIF_WORK_MASK \
151 (_TIF_SIGPENDING | _TIF_NEED_RESCHED | _TIF_NOTIFY_RESUME)
152 /* work to do on any return to u-space */
153 #define _TIF_ALLWORK_MASK (_TIF_NOHZ | _TIF_WORK_MASK | \
154 _TIF_WORK_SYSCALL_EXIT | \
155 _TIF_SYSCALL_TRACEPOINT)
156
157 /*
158 * We stash processor id into a COP0 register to retrieve it fast
159 * at kernel exception entry.
160 */
161 #if defined(CONFIG_MIPS_PGD_C0_CONTEXT)
162 #define SMP_CPUID_REG 20, 0 /* XCONTEXT */
163 #define ASM_SMP_CPUID_REG $20
164 #define SMP_CPUID_PTRSHIFT 48
165 #else
166 #define SMP_CPUID_REG 4, 0 /* CONTEXT */
167 #define ASM_SMP_CPUID_REG $4
168 #define SMP_CPUID_PTRSHIFT 23
169 #endif
170
171 #ifdef CONFIG_64BIT
172 #define SMP_CPUID_REGSHIFT (SMP_CPUID_PTRSHIFT + 3)
173 #else
174 #define SMP_CPUID_REGSHIFT (SMP_CPUID_PTRSHIFT + 2)
175 #endif
176
177 #define ASM_CPUID_MFC0 MFC0
178 #define UASM_i_CPUID_MFC0 UASM_i_MFC0
179
180 #endif /* __KERNEL__ */
181 #endif /* _ASM_THREAD_INFO_H */
182