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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 (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 __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 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 */
87extern int arch_dup_task_struct(struct task_struct *dst, struct task_struct *src);
88
89void arch_setup_new_exec(void);
90#define arch_setup_new_exec arch_setup_new_exec
91
92#endif /* __ASSEMBLER__ */
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_NEED_RESCHED_LAZY 9 /* Scheduler driven lazy preemption */
107#define TIF_SECCOMP 10 /* secure computing */
108#define TIF_RESTOREALL 11 /* Restore all regs (implies NOERROR) */
109#define TIF_NOERROR 12 /* Force successful syscall return */
110#define TIF_NOTIFY_RESUME 13 /* callback before returning to user */
111#define TIF_UPROBE 14 /* breakpointed or single-stepping */
112#define TIF_SYSCALL_TRACEPOINT 15 /* syscall tracepoint instrumentation */
113#define TIF_EMULATE_STACK_STORE 16 /* Is an instruction emulation
114 for stack store? */
115#define TIF_MEMDIE 17 /* is terminating due to OOM killer */
116#if defined(CONFIG_PPC64)
117#define TIF_ELF2ABI 18 /* function descriptors must die! */
118#endif
119#define TIF_POLLING_NRFLAG 19 /* true if poll_idle() is polling TIF_NEED_RESCHED */
120#define TIF_32BIT 20 /* 32 bit binary */
121
122/* as above, but as bit values */
123#define _TIF_SYSCALL_TRACE (1<<TIF_SYSCALL_TRACE)
124#define _TIF_SIGPENDING (1<<TIF_SIGPENDING)
125#define _TIF_NEED_RESCHED (1<<TIF_NEED_RESCHED)
126#define _TIF_NEED_RESCHED_LAZY (1<<TIF_NEED_RESCHED_LAZY)
127#define _TIF_NOTIFY_SIGNAL (1<<TIF_NOTIFY_SIGNAL)
128#define _TIF_POLLING_NRFLAG (1<<TIF_POLLING_NRFLAG)
129#define _TIF_32BIT (1<<TIF_32BIT)
130#define _TIF_RESTORE_TM (1<<TIF_RESTORE_TM)
131#define _TIF_PATCH_PENDING (1<<TIF_PATCH_PENDING)
132#define _TIF_SYSCALL_AUDIT (1<<TIF_SYSCALL_AUDIT)
133#define _TIF_SINGLESTEP (1<<TIF_SINGLESTEP)
134#define _TIF_SECCOMP (1<<TIF_SECCOMP)
135#define _TIF_RESTOREALL (1<<TIF_RESTOREALL)
136#define _TIF_NOERROR (1<<TIF_NOERROR)
137#define _TIF_NOTIFY_RESUME (1<<TIF_NOTIFY_RESUME)
138#define _TIF_UPROBE (1<<TIF_UPROBE)
139#define _TIF_SYSCALL_TRACEPOINT (1<<TIF_SYSCALL_TRACEPOINT)
140#define _TIF_EMULATE_STACK_STORE (1<<TIF_EMULATE_STACK_STORE)
141#define _TIF_SYSCALL_EMU (1<<TIF_SYSCALL_EMU)
142#define _TIF_SYSCALL_DOTRACE (_TIF_SYSCALL_TRACE | _TIF_SYSCALL_AUDIT | \
143 _TIF_SECCOMP | _TIF_SYSCALL_TRACEPOINT | \
144 _TIF_SYSCALL_EMU)
145
146#define _TIF_USER_WORK_MASK (_TIF_SIGPENDING | _TIF_NEED_RESCHED | \
147 _TIF_NEED_RESCHED_LAZY | _TIF_NOTIFY_RESUME | \
148 _TIF_UPROBE | _TIF_RESTORE_TM | \
149 _TIF_PATCH_PENDING | _TIF_NOTIFY_SIGNAL)
150
151#define _TIF_PERSYSCALL_MASK (_TIF_RESTOREALL|_TIF_NOERROR)
152
153/* Bits in local_flags */
154/* Don't move TLF_NAPPING without adjusting the code in entry_32.S */
155#define TLF_NAPPING 0 /* idle thread enabled NAP mode */
156#define TLF_SLEEPING 1 /* suspend code enabled SLEEP mode */
157#define TLF_LAZY_MMU 3 /* tlb_batch is active */
158#define TLF_RUNLATCH 4 /* Is the runlatch enabled? */
159
160#define _TLF_NAPPING (1 << TLF_NAPPING)
161#define _TLF_SLEEPING (1 << TLF_SLEEPING)
162#define _TLF_LAZY_MMU (1 << TLF_LAZY_MMU)
163#define _TLF_RUNLATCH (1 << TLF_RUNLATCH)
164
165#ifndef __ASSEMBLER__
166
167static inline void clear_thread_local_flags(unsigned int flags)
168{
169 struct thread_info *ti = current_thread_info();
170 ti->local_flags &= ~flags;
171}
172
173static inline bool test_thread_local_flags(unsigned int flags)
174{
175 struct thread_info *ti = current_thread_info();
176 return (ti->local_flags & flags) != 0;
177}
178
179#ifdef CONFIG_COMPAT
180#define is_32bit_task() (test_thread_flag(TIF_32BIT))
181#define is_tsk_32bit_task(tsk) (test_tsk_thread_flag(tsk, TIF_32BIT))
182#define clear_tsk_compat_task(tsk) (clear_tsk_thread_flag(p, TIF_32BIT))
183#else
184#define is_32bit_task() (IS_ENABLED(CONFIG_PPC32))
185#define is_tsk_32bit_task(tsk) (IS_ENABLED(CONFIG_PPC32))
186#define clear_tsk_compat_task(tsk) do { } while (0)
187#endif
188
189#if defined(CONFIG_PPC64)
190#define is_elf2_task() (test_thread_flag(TIF_ELF2ABI))
191#else
192#define is_elf2_task() (0)
193#endif
194
195/*
196 * Walks up the stack frames to make sure that the specified object is
197 * entirely contained by a single stack frame.
198 *
199 * Returns:
200 * GOOD_FRAME if within a frame
201 * BAD_STACK if placed across a frame boundary (or outside stack)
202 */
203static inline int arch_within_stack_frames(const void * const stack,
204 const void * const stackend,
205 const void *obj, unsigned long len)
206{
207 const void *params;
208 const void *frame;
209
210 params = *(const void * const *)current_stack_pointer + STACK_FRAME_PARAMS;
211 frame = **(const void * const * const *)current_stack_pointer;
212
213 /*
214 * low -----------------------------------------------------------> high
215 * [backchain][metadata][params][local vars][saved registers][backchain]
216 * ^------------------------------------^
217 * | allows copies only in this region |
218 * | |
219 * params frame
220 * The metadata region contains the saved LR, CR etc.
221 */
222 while (stack <= frame && frame < stackend) {
223 if (obj + len <= frame)
224 return obj >= params ? GOOD_FRAME : BAD_STACK;
225 params = frame + STACK_FRAME_PARAMS;
226 frame = *(const void * const *)frame;
227 }
228
229 return BAD_STACK;
230}
231
232#ifdef CONFIG_PPC32
233extern void *emergency_ctx[];
234#endif
235
236#endif /* !__ASSEMBLER__ */
237
238#endif /* __KERNEL__ */
239
240#endif /* _ASM_POWERPC_THREAD_INFO_H */