• Home
  • Line#
  • Scopes#
  • Navigate#
  • Raw
  • Download
1  /*
2   * Copyright (C) 2017 The Android Open Source Project
3   *
4   * Licensed under the Apache License, Version 2.0 (the "License");
5   * you may not use this file except in compliance with the License.
6   * You may obtain a copy of the License at
7   *
8   *      http://www.apache.org/licenses/LICENSE-2.0
9   *
10   * Unless required by applicable law or agreed to in writing, software
11   * distributed under the License is distributed on an "AS IS" BASIS,
12   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13   * See the License for the specific language governing permissions and
14   * limitations under the License.
15   */
16  
17  #include <stdint.h>
18  #include <string.h>
19  
20  #include <functional>
21  
22  #include <unwindstack/Elf.h>
23  #include <unwindstack/MachineMips64.h>
24  #include <unwindstack/MapInfo.h>
25  #include <unwindstack/Memory.h>
26  #include <unwindstack/RegsMips64.h>
27  #include <unwindstack/UcontextMips64.h>
28  #include <unwindstack/UserMips64.h>
29  
30  namespace unwindstack {
31  
RegsMips64()32  RegsMips64::RegsMips64()
33      : RegsImpl<uint64_t>(MIPS64_REG_LAST, Location(LOCATION_REGISTER, MIPS64_REG_RA)) {}
34  
Arch()35  ArchEnum RegsMips64::Arch() {
36    return ARCH_MIPS64;
37  }
38  
pc()39  uint64_t RegsMips64::pc() {
40    return regs_[MIPS64_REG_PC];
41  }
42  
sp()43  uint64_t RegsMips64::sp() {
44    return regs_[MIPS64_REG_SP];
45  }
46  
set_pc(uint64_t pc)47  void RegsMips64::set_pc(uint64_t pc) {
48    regs_[MIPS64_REG_PC] = pc;
49  }
50  
set_sp(uint64_t sp)51  void RegsMips64::set_sp(uint64_t sp) {
52    regs_[MIPS64_REG_SP] = sp;
53  }
54  
GetPcAdjustment(uint64_t rel_pc,Elf *)55  uint64_t RegsMips64::GetPcAdjustment(uint64_t rel_pc, Elf*) {
56    if (rel_pc < 8) {
57      return 0;
58    }
59    // For now, just assume no compact branches
60    return 8;
61  }
62  
SetPcFromReturnAddress(Memory *)63  bool RegsMips64::SetPcFromReturnAddress(Memory*) {
64    uint64_t ra = regs_[MIPS64_REG_RA];
65    if (regs_[MIPS64_REG_PC] == ra) {
66      return false;
67    }
68  
69    regs_[MIPS64_REG_PC] = ra;
70    return true;
71  }
72  
IterateRegisters(std::function<void (const char *,uint64_t)> fn)73  void RegsMips64::IterateRegisters(std::function<void(const char*, uint64_t)> fn) {
74    fn("r0", regs_[MIPS64_REG_R0]);
75    fn("r1", regs_[MIPS64_REG_R1]);
76    fn("r2", regs_[MIPS64_REG_R2]);
77    fn("r3", regs_[MIPS64_REG_R3]);
78    fn("r4", regs_[MIPS64_REG_R4]);
79    fn("r5", regs_[MIPS64_REG_R5]);
80    fn("r6", regs_[MIPS64_REG_R6]);
81    fn("r7", regs_[MIPS64_REG_R7]);
82    fn("r8", regs_[MIPS64_REG_R8]);
83    fn("r9", regs_[MIPS64_REG_R9]);
84    fn("r10", regs_[MIPS64_REG_R10]);
85    fn("r11", regs_[MIPS64_REG_R11]);
86    fn("r12", regs_[MIPS64_REG_R12]);
87    fn("r13", regs_[MIPS64_REG_R13]);
88    fn("r14", regs_[MIPS64_REG_R14]);
89    fn("r15", regs_[MIPS64_REG_R15]);
90    fn("r16", regs_[MIPS64_REG_R16]);
91    fn("r17", regs_[MIPS64_REG_R17]);
92    fn("r18", regs_[MIPS64_REG_R18]);
93    fn("r19", regs_[MIPS64_REG_R19]);
94    fn("r20", regs_[MIPS64_REG_R20]);
95    fn("r21", regs_[MIPS64_REG_R21]);
96    fn("r22", regs_[MIPS64_REG_R22]);
97    fn("r23", regs_[MIPS64_REG_R23]);
98    fn("r24", regs_[MIPS64_REG_R24]);
99    fn("r25", regs_[MIPS64_REG_R25]);
100    fn("r26", regs_[MIPS64_REG_R26]);
101    fn("r27", regs_[MIPS64_REG_R27]);
102    fn("r28", regs_[MIPS64_REG_R28]);
103    fn("sp", regs_[MIPS64_REG_SP]);
104    fn("r30", regs_[MIPS64_REG_R30]);
105    fn("ra", regs_[MIPS64_REG_RA]);
106    fn("pc", regs_[MIPS64_REG_PC]);
107  }
108  
Read(void * remote_data)109  Regs* RegsMips64::Read(void* remote_data) {
110    mips64_user_regs* user = reinterpret_cast<mips64_user_regs*>(remote_data);
111    RegsMips64* regs = new RegsMips64();
112    uint64_t* reg_data = reinterpret_cast<uint64_t*>(regs->RawData());
113  
114    memcpy(regs->RawData(), &user->regs[MIPS64_EF_R0], (MIPS64_REG_R31 + 1) * sizeof(uint64_t));
115  
116    reg_data[MIPS64_REG_PC] = user->regs[MIPS64_EF_CP0_EPC];
117    return regs;
118  }
119  
CreateFromUcontext(void * ucontext)120  Regs* RegsMips64::CreateFromUcontext(void* ucontext) {
121    mips64_ucontext_t* mips64_ucontext = reinterpret_cast<mips64_ucontext_t*>(ucontext);
122  
123    RegsMips64* regs = new RegsMips64();
124    // Copy 64 bit sc_regs over to 64 bit regs
125    memcpy(regs->RawData(), &mips64_ucontext->uc_mcontext.sc_regs[0], 32 * sizeof(uint64_t));
126    (*regs)[MIPS64_REG_PC] = mips64_ucontext->uc_mcontext.sc_pc;
127    return regs;
128  }
129  
StepIfSignalHandler(uint64_t elf_offset,Elf * elf,Memory * process_memory)130  bool RegsMips64::StepIfSignalHandler(uint64_t elf_offset, Elf* elf, Memory* process_memory) {
131    uint64_t data;
132    Memory* elf_memory = elf->memory();
133    // Read from elf memory since it is usually more expensive to read from
134    // process memory.
135    if (!elf_memory->Read(elf_offset, &data, sizeof(data))) {
136      return false;
137    }
138  
139    // Look for the kernel sigreturn function.
140    // __vdso_rt_sigreturn:
141    // 0x2402145b     li  v0, 0x145b
142    // 0x0000000c     syscall
143    if (data != 0x0000000c2402145bULL) {
144      return false;
145    }
146  
147    // vdso_rt_sigreturn => read rt_sigframe
148    // offset = siginfo offset + sizeof(siginfo) + uc_mcontext offset
149    // read 64 bit sc_regs[32] from stack into 64 bit regs_
150    uint64_t sp = regs_[MIPS64_REG_SP];
151    if (!process_memory->Read(sp + 24 + 128 + 40, regs_.data(),
152                              sizeof(uint64_t) * (MIPS64_REG_LAST - 1))) {
153      return false;
154    }
155  
156    // offset = siginfo offset + sizeof(siginfo) + uc_mcontext offset + sc_pc offset
157    // read 64 bit sc_pc from stack into 64 bit regs_[MIPS64_REG_PC]
158    if (!process_memory->Read(sp + 24 + 128 + 40 + 576, &regs_[MIPS64_REG_PC], sizeof(uint64_t))) {
159      return false;
160    }
161    return true;
162  }
163  
Clone()164  Regs* RegsMips64::Clone() {
165    return new RegsMips64(*this);
166  }
167  
168  }  // namespace unwindstack
169