1 // SPDX-License-Identifier: GPL-2.0-only
3 * Copyright (C) 2014-2016 Pratyush Anand <panand@redhat.com>
5 #include <linux/highmem.h>
6 #include <linux/ptrace.h>
7 #include <linux/uprobes.h>
8 #include <asm/cacheflush.h>
10 #include "decode-insn.h"
12 #define UPROBE_TRAP_NR UINT_MAX
14 bool is_swbp_insn(uprobe_opcode_t *insn)
16 return (*insn & 0xffff) == UPROBE_SWBP_INSN;
19 unsigned long uprobe_get_swbp_addr(struct pt_regs *regs)
21 return instruction_pointer(regs);
24 int arch_uprobe_analyze_insn(struct arch_uprobe *auprobe, struct mm_struct *mm,
29 insn = *(probe_opcode_t *)(&auprobe->insn[0]);
31 auprobe->insn_size = is_insn32(insn) ? 4 : 2;
33 switch (csky_probe_decode_insn(&insn, &auprobe->api)) {
37 case INSN_GOOD_NO_SLOT:
38 auprobe->simulate = true;
48 int arch_uprobe_pre_xol(struct arch_uprobe *auprobe, struct pt_regs *regs)
50 struct uprobe_task *utask = current->utask;
52 utask->autask.saved_trap_no = current->thread.trap_no;
53 current->thread.trap_no = UPROBE_TRAP_NR;
55 instruction_pointer_set(regs, utask->xol_vaddr);
57 user_enable_single_step(current);
62 int arch_uprobe_post_xol(struct arch_uprobe *auprobe, struct pt_regs *regs)
64 struct uprobe_task *utask = current->utask;
66 WARN_ON_ONCE(current->thread.trap_no != UPROBE_TRAP_NR);
68 instruction_pointer_set(regs, utask->vaddr + auprobe->insn_size);
70 user_disable_single_step(current);
75 bool arch_uprobe_xol_was_trapped(struct task_struct *t)
77 if (t->thread.trap_no != UPROBE_TRAP_NR)
83 bool arch_uprobe_skip_sstep(struct arch_uprobe *auprobe, struct pt_regs *regs)
88 if (!auprobe->simulate)
91 insn = *(probe_opcode_t *)(&auprobe->insn[0]);
92 addr = instruction_pointer(regs);
94 if (auprobe->api.handler)
95 auprobe->api.handler(insn, addr, regs);
100 void arch_uprobe_abort_xol(struct arch_uprobe *auprobe, struct pt_regs *regs)
102 struct uprobe_task *utask = current->utask;
105 * Task has received a fatal signal, so reset back to probbed
108 instruction_pointer_set(regs, utask->vaddr);
110 user_disable_single_step(current);
113 bool arch_uretprobe_is_alive(struct return_instance *ret, enum rp_check ctx,
114 struct pt_regs *regs)
116 if (ctx == RP_CHECK_CHAIN_CALL)
117 return regs->usp <= ret->stack;
119 return regs->usp < ret->stack;
123 arch_uretprobe_hijack_return_addr(unsigned long trampoline_vaddr,
124 struct pt_regs *regs)
130 regs->lr = trampoline_vaddr;
135 int arch_uprobe_exception_notify(struct notifier_block *self,
136 unsigned long val, void *data)
141 int uprobe_breakpoint_handler(struct pt_regs *regs)
143 if (uprobe_pre_sstep_notifier(regs))
149 int uprobe_single_step_handler(struct pt_regs *regs)
151 if (uprobe_post_sstep_notifier(regs))