1 /*
2 * Copyright (C) 2002 David Howells (dhowells@redhat.com)
3 * Copyright 2010 Tilera Corporation. All Rights Reserved.
4 *
5 * This program is free software; you can redistribute it and/or
6 * modify it under the terms of the GNU General Public License
7 * as published by the Free Software Foundation, version 2.
8 *
9 * This program is distributed in the hope that it will be useful, but
10 * WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
12 * NON INFRINGEMENT. See the GNU General Public License for
13 * more details.
14 */
15
16 #ifndef _ASM_TILE_THREAD_INFO_H
17 #define _ASM_TILE_THREAD_INFO_H
18
19 #include <asm/processor.h>
20 #include <asm/page.h>
21 #ifndef __ASSEMBLY__
22
23 /*
24 * Low level task data that assembly code needs immediate access to.
25 * The structure is placed at the bottom of the supervisor stack.
26 */
27 struct thread_info {
28 struct task_struct *task; /* main task structure */
29 unsigned long flags; /* low level flags */
30 unsigned long status; /* thread-synchronous flags */
31 __u32 homecache_cpu; /* CPU we are homecached on */
32 __u32 cpu; /* current CPU */
33 int preempt_count; /* 0 => preemptable,
34 <0 => BUG */
35
36 mm_segment_t addr_limit; /* thread address space
37 (KERNEL_DS or USER_DS) */
38 struct single_step_state *step_state; /* single step state
39 (if non-zero) */
40 int align_ctl; /* controls unaligned access */
41 #ifdef __tilegx__
42 unsigned long unalign_jit_tmp[4]; /* temp r0..r3 storage */
43 void __user *unalign_jit_base; /* unalign fixup JIT base */
44 #endif
45 };
46
47 /*
48 * macros/functions for gaining access to the thread information structure.
49 */
50 #define INIT_THREAD_INFO(tsk) \
51 { \
52 .task = &tsk, \
53 .flags = 0, \
54 .cpu = 0, \
55 .preempt_count = INIT_PREEMPT_COUNT, \
56 .addr_limit = KERNEL_DS, \
57 .step_state = NULL, \
58 .align_ctl = 0, \
59 }
60
61 #define init_thread_info (init_thread_union.thread_info)
62 #define init_stack (init_thread_union.stack)
63
64 #endif /* !__ASSEMBLY__ */
65
66 #if PAGE_SIZE < 8192
67 #define THREAD_SIZE_ORDER (13 - PAGE_SHIFT)
68 #else
69 #define THREAD_SIZE_ORDER (0)
70 #endif
71 #define THREAD_SIZE_PAGES (1 << THREAD_SIZE_ORDER)
72
73 #define THREAD_SIZE (PAGE_SIZE << THREAD_SIZE_ORDER)
74 #define LOG2_THREAD_SIZE (PAGE_SHIFT + THREAD_SIZE_ORDER)
75
76 #define STACK_WARN (THREAD_SIZE/8)
77
78 #ifndef __ASSEMBLY__
79
80 void arch_release_thread_info(struct thread_info *info);
81
82 /* How to get the thread information struct from C. */
83 register unsigned long stack_pointer __asm__("sp");
84
85 #define current_thread_info() \
86 ((struct thread_info *)(stack_pointer & -THREAD_SIZE))
87
88 /* Sit on a nap instruction until interrupted. */
89 extern void smp_nap(void);
90
91 /* Enable interrupts racelessly and nap forever: helper for arch_cpu_idle(). */
92 extern void _cpu_idle(void);
93
94 #else /* __ASSEMBLY__ */
95
96 /*
97 * How to get the thread information struct from assembly.
98 * Note that we use different macros since different architectures
99 * have different semantics in their "mm" instruction and we would
100 * like to guarantee that the macro expands to exactly one instruction.
101 */
102 #ifdef __tilegx__
103 #define EXTRACT_THREAD_INFO(reg) mm reg, zero, LOG2_THREAD_SIZE, 63
104 #else
105 #define GET_THREAD_INFO(reg) mm reg, sp, zero, LOG2_THREAD_SIZE, 31
106 #endif
107
108 #endif /* !__ASSEMBLY__ */
109
110 /*
111 * Thread information flags that various assembly files may need to access.
112 * Keep flags accessed frequently in low bits, particular since it makes
113 * it easier to build constants in assembly.
114 */
115 #define TIF_SIGPENDING 0 /* signal pending */
116 #define TIF_NEED_RESCHED 1 /* rescheduling necessary */
117 #define TIF_SINGLESTEP 2 /* restore singlestep on return to
118 user mode */
119 #define TIF_ASYNC_TLB 3 /* got an async TLB fault in kernel */
120 #define TIF_SYSCALL_TRACE 4 /* syscall trace active */
121 #define TIF_SYSCALL_AUDIT 5 /* syscall auditing active */
122 #define TIF_SECCOMP 6 /* secure computing */
123 #define TIF_MEMDIE 7 /* OOM killer at work */
124 #define TIF_NOTIFY_RESUME 8 /* callback before returning to user */
125 #define TIF_SYSCALL_TRACEPOINT 9 /* syscall tracepoint instrumentation */
126 #define TIF_POLLING_NRFLAG 10 /* idle is polling for TIF_NEED_RESCHED */
127 #define TIF_NOHZ 11 /* in adaptive nohz mode */
128
129 #define _TIF_SIGPENDING (1<<TIF_SIGPENDING)
130 #define _TIF_NEED_RESCHED (1<<TIF_NEED_RESCHED)
131 #define _TIF_SINGLESTEP (1<<TIF_SINGLESTEP)
132 #define _TIF_ASYNC_TLB (1<<TIF_ASYNC_TLB)
133 #define _TIF_SYSCALL_TRACE (1<<TIF_SYSCALL_TRACE)
134 #define _TIF_SYSCALL_AUDIT (1<<TIF_SYSCALL_AUDIT)
135 #define _TIF_SECCOMP (1<<TIF_SECCOMP)
136 #define _TIF_MEMDIE (1<<TIF_MEMDIE)
137 #define _TIF_NOTIFY_RESUME (1<<TIF_NOTIFY_RESUME)
138 #define _TIF_SYSCALL_TRACEPOINT (1<<TIF_SYSCALL_TRACEPOINT)
139 #define _TIF_POLLING_NRFLAG (1<<TIF_POLLING_NRFLAG)
140 #define _TIF_NOHZ (1<<TIF_NOHZ)
141
142 /* Work to do on any return to user space. */
143 #define _TIF_ALLWORK_MASK \
144 (_TIF_SIGPENDING | _TIF_NEED_RESCHED | _TIF_SINGLESTEP | \
145 _TIF_ASYNC_TLB | _TIF_NOTIFY_RESUME | _TIF_NOHZ)
146
147 /* Work to do at syscall entry. */
148 #define _TIF_SYSCALL_ENTRY_WORK \
149 (_TIF_SYSCALL_TRACE | _TIF_SYSCALL_TRACEPOINT | _TIF_NOHZ)
150
151 /* Work to do at syscall exit. */
152 #define _TIF_SYSCALL_EXIT_WORK (_TIF_SYSCALL_TRACE | _TIF_SYSCALL_TRACEPOINT)
153
154 /*
155 * Thread-synchronous status.
156 *
157 * This is different from the flags in that nobody else
158 * ever touches our thread-synchronous status, so we don't
159 * have to worry about atomic accesses.
160 */
161 #ifdef __tilegx__
162 #define TS_COMPAT 0x0001 /* 32-bit compatibility mode */
163 #endif
164 #define TS_RESTORE_SIGMASK 0x0008 /* restore signal mask in do_signal */
165
166 #ifndef __ASSEMBLY__
167 #define HAVE_SET_RESTORE_SIGMASK 1
set_restore_sigmask(void)168 static inline void set_restore_sigmask(void)
169 {
170 struct thread_info *ti = current_thread_info();
171 ti->status |= TS_RESTORE_SIGMASK;
172 WARN_ON(!test_bit(TIF_SIGPENDING, &ti->flags));
173 }
clear_restore_sigmask(void)174 static inline void clear_restore_sigmask(void)
175 {
176 current_thread_info()->status &= ~TS_RESTORE_SIGMASK;
177 }
test_restore_sigmask(void)178 static inline bool test_restore_sigmask(void)
179 {
180 return current_thread_info()->status & TS_RESTORE_SIGMASK;
181 }
test_and_clear_restore_sigmask(void)182 static inline bool test_and_clear_restore_sigmask(void)
183 {
184 struct thread_info *ti = current_thread_info();
185 if (!(ti->status & TS_RESTORE_SIGMASK))
186 return false;
187 ti->status &= ~TS_RESTORE_SIGMASK;
188 return true;
189 }
190 #endif /* !__ASSEMBLY__ */
191
192 #endif /* _ASM_TILE_THREAD_INFO_H */
193