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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 ([email protected])
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 __ASSEMBLER__
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 */
54struct thread_info {
55 int preempt_count; /* 0 => preemptable,
56 <0 => BUG */
57#ifdef CONFIG_SMP
58 unsigned int cpu;
59#endif
60 unsigned long exit_flags; /* Exit Flags for entry/exit */
61 unsigned long syscall_work; /* SYSCALL_WORK_ flags */
62 unsigned long local_flags; /* private flags for thread */
63#ifdef CONFIG_LIVEPATCH_64
64 unsigned long *livepatch_sp;
65#endif
66#if defined(CONFIG_VIRT_CPU_ACCOUNTING_NATIVE) && defined(CONFIG_PPC32)
67 struct cpu_accounting_data accounting;
68#endif
69 unsigned char slb_preload_nr;
70 unsigned char slb_preload_tail;
71 u32 slb_preload_esid[SLB_PRELOAD_NR];
72
73 /* low level flags - has atomic operations done on it */
74 unsigned long flags ____cacheline_aligned_in_smp;
75};
76
77/*
78 * macros/functions for gaining access to the thread information structure
79 */
80#define INIT_THREAD_INFO(tsk) \
81{ \
82 .preempt_count = INIT_PREEMPT_COUNT, \
83 .flags = 0, \
84}
85
86#define THREAD_SIZE_ORDER (THREAD_SHIFT - PAGE_SHIFT)
87
88/* how to get the thread information struct from C */
89extern int arch_dup_task_struct(struct task_struct *dst, struct task_struct *src);
90
91void arch_setup_new_exec(void);
92#define arch_setup_new_exec arch_setup_new_exec
93
94#endif /* __ASSEMBLER__ */
95
96/*
97 * thread information flag bit numbers
98 */
99#define TIF_SYSCALL_TRACE 0 /* syscall trace active */
100#define TIF_SIGPENDING 1 /* signal pending */
101#define TIF_NEED_RESCHED 2 /* rescheduling necessary */
102#define TIF_NOTIFY_SIGNAL 3 /* signal notifications exist */
103#define TIF_SYSCALL_EMU 4 /* syscall emulation active */
104#define TIF_RESTORE_TM 5 /* need to restore TM FP/VEC/VSX */
105#define TIF_PATCH_PENDING 6 /* pending live patching update */
106#define TIF_SYSCALL_AUDIT 7 /* syscall auditing active */
107#define TIF_SINGLESTEP 8 /* singlestepping active */
108#define TIF_NEED_RESCHED_LAZY 9 /* Scheduler driven lazy preemption */
109#define TIF_SECCOMP 10 /* secure computing */
110#define TIF_RESTOREALL 11 /* Restore all regs (implies NOERROR) */
111#define TIF_NOERROR 12 /* Force successful syscall return */
112#define TIF_NOTIFY_RESUME 13 /* callback before returning to user */
113#define TIF_UPROBE 14 /* breakpointed or single-stepping */
114#define TIF_SYSCALL_TRACEPOINT 15 /* syscall tracepoint instrumentation */
115#define TIF_EMULATE_STACK_STORE 16 /* Is an instruction emulation
116 for stack store? */
117#define TIF_MEMDIE 17 /* is terminating due to OOM killer */
118#if defined(CONFIG_PPC64)
119#define TIF_ELF2ABI 18 /* function descriptors must die! */
120#endif
121#define TIF_POLLING_NRFLAG 19 /* true if poll_idle() is polling TIF_NEED_RESCHED */
122#define TIF_32BIT 20 /* 32 bit binary */
123#define TIF_SYSCALL_RET 21 /* syscall error value set */
124
125/* as above, but as bit values */
126#define _TIF_SYSCALL_TRACE (1<<TIF_SYSCALL_TRACE)
127#define _TIF_SIGPENDING (1<<TIF_SIGPENDING)
128#define _TIF_NEED_RESCHED (1<<TIF_NEED_RESCHED)
129#define _TIF_NEED_RESCHED_LAZY (1<<TIF_NEED_RESCHED_LAZY)
130#define _TIF_NOTIFY_SIGNAL (1<<TIF_NOTIFY_SIGNAL)
131#define _TIF_POLLING_NRFLAG (1<<TIF_POLLING_NRFLAG)
132#define _TIF_32BIT (1<<TIF_32BIT)
133#define _TIF_RESTORE_TM (1<<TIF_RESTORE_TM)
134#define _TIF_PATCH_PENDING (1<<TIF_PATCH_PENDING)
135#define _TIF_SYSCALL_AUDIT (1<<TIF_SYSCALL_AUDIT)
136#define _TIF_SINGLESTEP (1<<TIF_SINGLESTEP)
137#define _TIF_SECCOMP (1<<TIF_SECCOMP)
138#define _TIF_RESTOREALL (1<<TIF_RESTOREALL)
139#define _TIF_NOERROR (1<<TIF_NOERROR)
140#define _TIF_NOTIFY_RESUME (1<<TIF_NOTIFY_RESUME)
141#define _TIF_UPROBE (1<<TIF_UPROBE)
142#define _TIF_SYSCALL_TRACEPOINT (1<<TIF_SYSCALL_TRACEPOINT)
143#define _TIF_EMULATE_STACK_STORE (1<<TIF_EMULATE_STACK_STORE)
144#define _TIF_SYSCALL_EMU (1<<TIF_SYSCALL_EMU)
145#define _TIF_SYSCALL_DOTRACE (_TIF_SYSCALL_TRACE | _TIF_SYSCALL_AUDIT | \
146 _TIF_SECCOMP | _TIF_SYSCALL_TRACEPOINT | \
147 _TIF_SYSCALL_EMU)
148
149#define _TIF_USER_WORK_MASK (_TIF_SIGPENDING | _TIF_NEED_RESCHED | \
150 _TIF_NEED_RESCHED_LAZY | _TIF_NOTIFY_RESUME | \
151 _TIF_UPROBE | _TIF_RESTORE_TM | \
152 _TIF_PATCH_PENDING | _TIF_NOTIFY_SIGNAL)
153
154#define _TIF_PERSYSCALL_MASK (_TIF_RESTOREALL|_TIF_NOERROR)
155
156/* Bits in local_flags */
157/* Don't move TLF_NAPPING without adjusting the code in entry_32.S */
158#define TLF_NAPPING 0 /* idle thread enabled NAP mode */
159#define TLF_SLEEPING 1 /* suspend code enabled SLEEP mode */
160#define TLF_RUNLATCH 4 /* Is the runlatch enabled? */
161
162#define _TLF_NAPPING (1 << TLF_NAPPING)
163#define _TLF_SLEEPING (1 << TLF_SLEEPING)
164#define _TLF_RUNLATCH (1 << TLF_RUNLATCH)
165
166#ifndef __ASSEMBLER__
167
168static inline void clear_thread_local_flags(unsigned int flags)
169{
170 struct thread_info *ti = current_thread_info();
171 ti->local_flags &= ~flags;
172}
173
174static inline bool test_thread_local_flags(unsigned int flags)
175{
176 struct thread_info *ti = current_thread_info();
177 return (ti->local_flags & flags) != 0;
178}
179
180#ifdef CONFIG_COMPAT
181#define is_32bit_task() (test_thread_flag(TIF_32BIT))
182#define is_tsk_32bit_task(tsk) (test_tsk_thread_flag(tsk, TIF_32BIT))
183#define clear_tsk_compat_task(tsk) (clear_tsk_thread_flag(p, TIF_32BIT))
184#else
185#define is_32bit_task() (IS_ENABLED(CONFIG_PPC32))
186#define is_tsk_32bit_task(tsk) (IS_ENABLED(CONFIG_PPC32))
187#define clear_tsk_compat_task(tsk) do { } while (0)
188#endif
189
190#if defined(CONFIG_PPC64)
191#define is_elf2_task() (test_thread_flag(TIF_ELF2ABI))
192#else
193#define is_elf2_task() (0)
194#endif
195
196/*
197 * Walks up the stack frames to make sure that the specified object is
198 * entirely contained by a single stack frame.
199 *
200 * Returns:
201 * GOOD_FRAME if within a frame
202 * BAD_STACK if placed across a frame boundary (or outside stack)
203 */
204static inline int arch_within_stack_frames(const void * const stack,
205 const void * const stackend,
206 const void *obj, unsigned long len)
207{
208 const void *params;
209 const void *frame;
210
211 params = *(const void * const *)current_stack_pointer + STACK_FRAME_PARAMS;
212 frame = **(const void * const * const *)current_stack_pointer;
213
214 /*
215 * low -----------------------------------------------------------> high
216 * [backchain][metadata][params][local vars][saved registers][backchain]
217 * ^------------------------------------^
218 * | allows copies only in this region |
219 * | |
220 * params frame
221 * The metadata region contains the saved LR, CR etc.
222 */
223 while (stack <= frame && frame < stackend) {
224 if (obj + len <= frame)
225 return obj >= params ? GOOD_FRAME : BAD_STACK;
226 params = frame + STACK_FRAME_PARAMS;
227 frame = *(const void * const *)frame;
228 }
229
230 return BAD_STACK;
231}
232
233#ifdef CONFIG_PPC32
234extern void *emergency_ctx[];
235#endif
236
237#endif /* !__ASSEMBLER__ */
238
239#endif /* __KERNEL__ */
240
241#endif /* _ASM_POWERPC_THREAD_INFO_H */