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 struct exec_domain *exec_domain; /* execution domain */
30 unsigned long flags; /* low level flags */
31 unsigned long status; /* thread-synchronous flags */
32 __u32 homecache_cpu; /* CPU we are homecached on */
33 __u32 cpu; /* current CPU */
34 int preempt_count; /* 0 => preemptable,
35 <0 => BUG */
36
37 mm_segment_t addr_limit; /* thread address space
38 (KERNEL_DS or USER_DS) */
39 struct single_step_state *step_state; /* single step state
40 (if non-zero) */
41 int align_ctl; /* controls unaligned access */
42 #ifdef __tilegx__
43 unsigned long unalign_jit_tmp[4]; /* temp r0..r3 storage */
44 void __user *unalign_jit_base; /* unalign fixup JIT base */
45 #endif
46 };
47
48 /*
49 * macros/functions for gaining access to the thread information structure.
50 */
51 #define INIT_THREAD_INFO(tsk) \
52 { \
53 .task = &tsk, \
54 .exec_domain = &default_exec_domain, \
55 .flags = 0, \
56 .cpu = 0, \
57 .preempt_count = INIT_PREEMPT_COUNT, \
58 .addr_limit = KERNEL_DS, \
59 .step_state = NULL, \
60 .align_ctl = 0, \
61 }
62
63 #define init_thread_info (init_thread_union.thread_info)
64 #define init_stack (init_thread_union.stack)
65
66 #endif /* !__ASSEMBLY__ */
67
68 #if PAGE_SIZE < 8192
69 #define THREAD_SIZE_ORDER (13 - PAGE_SHIFT)
70 #else
71 #define THREAD_SIZE_ORDER (0)
72 #endif
73 #define THREAD_SIZE_PAGES (1 << THREAD_SIZE_ORDER)
74
75 #define THREAD_SIZE (PAGE_SIZE << THREAD_SIZE_ORDER)
76 #define LOG2_THREAD_SIZE (PAGE_SHIFT + THREAD_SIZE_ORDER)
77
78 #define STACK_WARN (THREAD_SIZE/8)
79
80 #ifndef __ASSEMBLY__
81
82 void arch_release_thread_info(struct thread_info *info);
83
84 /* How to get the thread information struct from C. */
85 register unsigned long stack_pointer __asm__("sp");
86
87 #define current_thread_info() \
88 ((struct thread_info *)(stack_pointer & -THREAD_SIZE))
89
90 /* Sit on a nap instruction until interrupted. */
91 extern void smp_nap(void);
92
93 /* Enable interrupts racelessly and nap forever: helper for arch_cpu_idle(). */
94 extern void _cpu_idle(void);
95
96 #else /* __ASSEMBLY__ */
97
98 /*
99 * How to get the thread information struct from assembly.
100 * Note that we use different macros since different architectures
101 * have different semantics in their "mm" instruction and we would
102 * like to guarantee that the macro expands to exactly one instruction.
103 */
104 #ifdef __tilegx__
105 #define EXTRACT_THREAD_INFO(reg) mm reg, zero, LOG2_THREAD_SIZE, 63
106 #else
107 #define GET_THREAD_INFO(reg) mm reg, sp, zero, LOG2_THREAD_SIZE, 31
108 #endif
109
110 #endif /* !__ASSEMBLY__ */
111
112 /*
113 * Thread information flags that various assembly files may need to access.
114 * Keep flags accessed frequently in low bits, particular since it makes
115 * it easier to build constants in assembly.
116 */
117 #define TIF_SIGPENDING 0 /* signal pending */
118 #define TIF_NEED_RESCHED 1 /* rescheduling necessary */
119 #define TIF_SINGLESTEP 2 /* restore singlestep on return to
120 user mode */
121 #define TIF_ASYNC_TLB 3 /* got an async TLB fault in kernel */
122 #define TIF_SYSCALL_TRACE 4 /* syscall trace active */
123 #define TIF_SYSCALL_AUDIT 5 /* syscall auditing active */
124 #define TIF_SECCOMP 6 /* secure computing */
125 #define TIF_MEMDIE 7 /* OOM killer at work */
126 #define TIF_NOTIFY_RESUME 8 /* callback before returning to user */
127 #define TIF_SYSCALL_TRACEPOINT 9 /* syscall tracepoint instrumentation */
128 #define TIF_POLLING_NRFLAG 10 /* idle is polling for TIF_NEED_RESCHED */
129
130 #define _TIF_SIGPENDING (1<<TIF_SIGPENDING)
131 #define _TIF_NEED_RESCHED (1<<TIF_NEED_RESCHED)
132 #define _TIF_SINGLESTEP (1<<TIF_SINGLESTEP)
133 #define _TIF_ASYNC_TLB (1<<TIF_ASYNC_TLB)
134 #define _TIF_SYSCALL_TRACE (1<<TIF_SYSCALL_TRACE)
135 #define _TIF_SYSCALL_AUDIT (1<<TIF_SYSCALL_AUDIT)
136 #define _TIF_SECCOMP (1<<TIF_SECCOMP)
137 #define _TIF_MEMDIE (1<<TIF_MEMDIE)
138 #define _TIF_NOTIFY_RESUME (1<<TIF_NOTIFY_RESUME)
139 #define _TIF_SYSCALL_TRACEPOINT (1<<TIF_SYSCALL_TRACEPOINT)
140 #define _TIF_POLLING_NRFLAG (1<<TIF_POLLING_NRFLAG)
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)
146
147 /* Work to do at syscall entry. */
148 #define _TIF_SYSCALL_ENTRY_WORK (_TIF_SYSCALL_TRACE | _TIF_SYSCALL_TRACEPOINT)
149
150 /* Work to do at syscall exit. */
151 #define _TIF_SYSCALL_EXIT_WORK (_TIF_SYSCALL_TRACE | _TIF_SYSCALL_TRACEPOINT)
152
153 /*
154 * Thread-synchronous status.
155 *
156 * This is different from the flags in that nobody else
157 * ever touches our thread-synchronous status, so we don't
158 * have to worry about atomic accesses.
159 */
160 #ifdef __tilegx__
161 #define TS_COMPAT 0x0001 /* 32-bit compatibility mode */
162 #endif
163 #define TS_RESTORE_SIGMASK 0x0008 /* restore signal mask in do_signal */
164
165 #ifndef __ASSEMBLY__
166 #define HAVE_SET_RESTORE_SIGMASK 1
set_restore_sigmask(void)167 static inline void set_restore_sigmask(void)
168 {
169 struct thread_info *ti = current_thread_info();
170 ti->status |= TS_RESTORE_SIGMASK;
171 WARN_ON(!test_bit(TIF_SIGPENDING, &ti->flags));
172 }
clear_restore_sigmask(void)173 static inline void clear_restore_sigmask(void)
174 {
175 current_thread_info()->status &= ~TS_RESTORE_SIGMASK;
176 }
test_restore_sigmask(void)177 static inline bool test_restore_sigmask(void)
178 {
179 return current_thread_info()->status & TS_RESTORE_SIGMASK;
180 }
test_and_clear_restore_sigmask(void)181 static inline bool test_and_clear_restore_sigmask(void)
182 {
183 struct thread_info *ti = current_thread_info();
184 if (!(ti->status & TS_RESTORE_SIGMASK))
185 return false;
186 ti->status &= ~TS_RESTORE_SIGMASK;
187 return true;
188 }
189 #endif /* !__ASSEMBLY__ */
190
191 #endif /* _ASM_TILE_THREAD_INFO_H */
192