1 /* SPDX-License-Identifier: GPL-2.0 */
2 /* thread_info.h: PowerPC low-level thread information
3 * adapted from the i386 version by Paul Mackerras
4 *
5 * Copyright (C) 2002 David Howells (dhowells@redhat.com)
6 * - Incorporating suggestions made by Linus Torvalds and Dave Miller
7 */
8
9 #ifndef _ASM_POWERPC_THREAD_INFO_H
10 #define _ASM_POWERPC_THREAD_INFO_H
11
12 #include <asm/asm-const.h>
13 #include <asm/page.h>
14
15 #ifdef __KERNEL__
16
17 #if defined(CONFIG_KASAN) && CONFIG_THREAD_SHIFT < 15
18 #define MIN_THREAD_SHIFT (CONFIG_THREAD_SHIFT + 1)
19 #else
20 #define MIN_THREAD_SHIFT CONFIG_THREAD_SHIFT
21 #endif
22
23 #if defined(CONFIG_VMAP_STACK) && MIN_THREAD_SHIFT < PAGE_SHIFT
24 #define THREAD_SHIFT PAGE_SHIFT
25 #else
26 #define THREAD_SHIFT MIN_THREAD_SHIFT
27 #endif
28
29 #define THREAD_SIZE (1 << THREAD_SHIFT)
30
31 /*
32 * By aligning VMAP'd stacks to 2 * THREAD_SIZE, we can detect overflow by
33 * checking sp & (1 << THREAD_SHIFT), which we can do cheaply in the entry
34 * assembly.
35 */
36 #ifdef CONFIG_VMAP_STACK
37 #define THREAD_ALIGN_SHIFT (THREAD_SHIFT + 1)
38 #else
39 #define THREAD_ALIGN_SHIFT THREAD_SHIFT
40 #endif
41
42 #define THREAD_ALIGN (1 << THREAD_ALIGN_SHIFT)
43
44 #ifndef __ASSEMBLY__
45 #include <linux/cache.h>
46 #include <asm/processor.h>
47 #include <asm/accounting.h>
48 #include <asm/ppc_asm.h>
49
50 #define SLB_PRELOAD_NR 16U
51 /*
52 * low level task data.
53 */
54 struct thread_info {
55 int preempt_count; /* 0 => preemptable,
56 <0 => BUG */
57 #ifdef CONFIG_SMP
58 unsigned int cpu;
59 #endif
60 unsigned long local_flags; /* private flags for thread */
61 #ifdef CONFIG_LIVEPATCH_64
62 unsigned long *livepatch_sp;
63 #endif
64 #if defined(CONFIG_VIRT_CPU_ACCOUNTING_NATIVE) && defined(CONFIG_PPC32)
65 struct cpu_accounting_data accounting;
66 #endif
67 unsigned char slb_preload_nr;
68 unsigned char slb_preload_tail;
69 u32 slb_preload_esid[SLB_PRELOAD_NR];
70
71 /* low level flags - has atomic operations done on it */
72 unsigned long flags ____cacheline_aligned_in_smp;
73 };
74
75 /*
76 * macros/functions for gaining access to the thread information structure
77 */
78 #define INIT_THREAD_INFO(tsk) \
79 { \
80 .preempt_count = INIT_PREEMPT_COUNT, \
81 .flags = 0, \
82 }
83
84 #define THREAD_SIZE_ORDER (THREAD_SHIFT - PAGE_SHIFT)
85
86 /* how to get the thread information struct from C */
87 extern int arch_dup_task_struct(struct task_struct *dst, struct task_struct *src);
88
89 void arch_setup_new_exec(void);
90 #define arch_setup_new_exec arch_setup_new_exec
91
92 #endif /* __ASSEMBLY__ */
93
94 /*
95 * thread information flag bit numbers
96 */
97 #define TIF_SYSCALL_TRACE 0 /* syscall trace active */
98 #define TIF_SIGPENDING 1 /* signal pending */
99 #define TIF_NEED_RESCHED 2 /* rescheduling necessary */
100 #define TIF_NOTIFY_SIGNAL 3 /* signal notifications exist */
101 #define TIF_SYSCALL_EMU 4 /* syscall emulation active */
102 #define TIF_RESTORE_TM 5 /* need to restore TM FP/VEC/VSX */
103 #define TIF_PATCH_PENDING 6 /* pending live patching update */
104 #define TIF_SYSCALL_AUDIT 7 /* syscall auditing active */
105 #define TIF_SINGLESTEP 8 /* singlestepping active */
106 #define TIF_SECCOMP 10 /* secure computing */
107 #define TIF_RESTOREALL 11 /* Restore all regs (implies NOERROR) */
108 #define TIF_NOERROR 12 /* Force successful syscall return */
109 #define TIF_NOTIFY_RESUME 13 /* callback before returning to user */
110 #define TIF_UPROBE 14 /* breakpointed or single-stepping */
111 #define TIF_SYSCALL_TRACEPOINT 15 /* syscall tracepoint instrumentation */
112 #define TIF_EMULATE_STACK_STORE 16 /* Is an instruction emulation
113 for stack store? */
114 #define TIF_MEMDIE 17 /* is terminating due to OOM killer */
115 #if defined(CONFIG_PPC64)
116 #define TIF_ELF2ABI 18 /* function descriptors must die! */
117 #endif
118 #define TIF_POLLING_NRFLAG 19 /* true if poll_idle() is polling TIF_NEED_RESCHED */
119 #define TIF_32BIT 20 /* 32 bit binary */
120
121 /* as above, but as bit values */
122 #define _TIF_SYSCALL_TRACE (1<<TIF_SYSCALL_TRACE)
123 #define _TIF_SIGPENDING (1<<TIF_SIGPENDING)
124 #define _TIF_NEED_RESCHED (1<<TIF_NEED_RESCHED)
125 #define _TIF_NOTIFY_SIGNAL (1<<TIF_NOTIFY_SIGNAL)
126 #define _TIF_POLLING_NRFLAG (1<<TIF_POLLING_NRFLAG)
127 #define _TIF_32BIT (1<<TIF_32BIT)
128 #define _TIF_RESTORE_TM (1<<TIF_RESTORE_TM)
129 #define _TIF_PATCH_PENDING (1<<TIF_PATCH_PENDING)
130 #define _TIF_SYSCALL_AUDIT (1<<TIF_SYSCALL_AUDIT)
131 #define _TIF_SINGLESTEP (1<<TIF_SINGLESTEP)
132 #define _TIF_SECCOMP (1<<TIF_SECCOMP)
133 #define _TIF_RESTOREALL (1<<TIF_RESTOREALL)
134 #define _TIF_NOERROR (1<<TIF_NOERROR)
135 #define _TIF_NOTIFY_RESUME (1<<TIF_NOTIFY_RESUME)
136 #define _TIF_UPROBE (1<<TIF_UPROBE)
137 #define _TIF_SYSCALL_TRACEPOINT (1<<TIF_SYSCALL_TRACEPOINT)
138 #define _TIF_EMULATE_STACK_STORE (1<<TIF_EMULATE_STACK_STORE)
139 #define _TIF_SYSCALL_EMU (1<<TIF_SYSCALL_EMU)
140 #define _TIF_SYSCALL_DOTRACE (_TIF_SYSCALL_TRACE | _TIF_SYSCALL_AUDIT | \
141 _TIF_SECCOMP | _TIF_SYSCALL_TRACEPOINT | \
142 _TIF_SYSCALL_EMU)
143
144 #define _TIF_USER_WORK_MASK (_TIF_SIGPENDING | _TIF_NEED_RESCHED | \
145 _TIF_NOTIFY_RESUME | _TIF_UPROBE | \
146 _TIF_RESTORE_TM | _TIF_PATCH_PENDING | \
147 _TIF_NOTIFY_SIGNAL)
148 #define _TIF_PERSYSCALL_MASK (_TIF_RESTOREALL|_TIF_NOERROR)
149
150 /* Bits in local_flags */
151 /* Don't move TLF_NAPPING without adjusting the code in entry_32.S */
152 #define TLF_NAPPING 0 /* idle thread enabled NAP mode */
153 #define TLF_SLEEPING 1 /* suspend code enabled SLEEP mode */
154 #define TLF_LAZY_MMU 3 /* tlb_batch is active */
155 #define TLF_RUNLATCH 4 /* Is the runlatch enabled? */
156
157 #define _TLF_NAPPING (1 << TLF_NAPPING)
158 #define _TLF_SLEEPING (1 << TLF_SLEEPING)
159 #define _TLF_LAZY_MMU (1 << TLF_LAZY_MMU)
160 #define _TLF_RUNLATCH (1 << TLF_RUNLATCH)
161
162 #ifndef __ASSEMBLY__
163
clear_thread_local_flags(unsigned int flags)164 static inline void clear_thread_local_flags(unsigned int flags)
165 {
166 struct thread_info *ti = current_thread_info();
167 ti->local_flags &= ~flags;
168 }
169
test_thread_local_flags(unsigned int flags)170 static inline bool test_thread_local_flags(unsigned int flags)
171 {
172 struct thread_info *ti = current_thread_info();
173 return (ti->local_flags & flags) != 0;
174 }
175
176 #ifdef CONFIG_COMPAT
177 #define is_32bit_task() (test_thread_flag(TIF_32BIT))
178 #define is_tsk_32bit_task(tsk) (test_tsk_thread_flag(tsk, TIF_32BIT))
179 #define clear_tsk_compat_task(tsk) (clear_tsk_thread_flag(p, TIF_32BIT))
180 #else
181 #define is_32bit_task() (IS_ENABLED(CONFIG_PPC32))
182 #define is_tsk_32bit_task(tsk) (IS_ENABLED(CONFIG_PPC32))
183 #define clear_tsk_compat_task(tsk) do { } while (0)
184 #endif
185
186 #if defined(CONFIG_PPC64)
187 #define is_elf2_task() (test_thread_flag(TIF_ELF2ABI))
188 #else
189 #define is_elf2_task() (0)
190 #endif
191
192 /*
193 * Walks up the stack frames to make sure that the specified object is
194 * entirely contained by a single stack frame.
195 *
196 * Returns:
197 * GOOD_FRAME if within a frame
198 * BAD_STACK if placed across a frame boundary (or outside stack)
199 */
arch_within_stack_frames(const void * const stack,const void * const stackend,const void * obj,unsigned long len)200 static inline int arch_within_stack_frames(const void * const stack,
201 const void * const stackend,
202 const void *obj, unsigned long len)
203 {
204 const void *params;
205 const void *frame;
206
207 params = *(const void * const *)current_stack_pointer + STACK_FRAME_PARAMS;
208 frame = **(const void * const * const *)current_stack_pointer;
209
210 /*
211 * low -----------------------------------------------------------> high
212 * [backchain][metadata][params][local vars][saved registers][backchain]
213 * ^------------------------------------^
214 * | allows copies only in this region |
215 * | |
216 * params frame
217 * The metadata region contains the saved LR, CR etc.
218 */
219 while (stack <= frame && frame < stackend) {
220 if (obj + len <= frame)
221 return obj >= params ? GOOD_FRAME : BAD_STACK;
222 params = frame + STACK_FRAME_PARAMS;
223 frame = *(const void * const *)frame;
224 }
225
226 return BAD_STACK;
227 }
228
229 #ifdef CONFIG_PPC32
230 extern void *emergency_ctx[];
231 #endif
232
233 #endif /* !__ASSEMBLY__ */
234
235 #endif /* __KERNEL__ */
236
237 #endif /* _ASM_POWERPC_THREAD_INFO_H */
238