gdbstub/internals.h

   1 /*
   2  * gdbstub internals
   3  *
   4  * Copyright (c) 2022 Linaro Ltd
   5  *
   6  * SPDX-License-Identifier: GPL-2.0-or-later
   7  */
   8
   9 #ifndef GDBSTUB_INTERNALS_H
  10 #define GDBSTUB_INTERNALS_H
  11
  12 #include "exec/cpu-common.h"
  13
  14 #define MAX_PACKET_LENGTH 4096
  15
  16 /*
  17  * Shared structures and definitions
  18  */
  19
  20 enum {
  21     GDB_SIGNAL_0 = 0,
  22     GDB_SIGNAL_INT = 2,
  23     GDB_SIGNAL_QUIT = 3,
  24     GDB_SIGNAL_TRAP = 5,
  25     GDB_SIGNAL_ABRT = 6,
  26     GDB_SIGNAL_ALRM = 14,
  27     GDB_SIGNAL_IO = 23,
  28     GDB_SIGNAL_XCPU = 24,
  29     GDB_SIGNAL_UNKNOWN = 143
  30 };
  31
  32 typedef struct GDBProcess {
  33     uint32_t pid;
  34     bool attached;
  35
  36     char target_xml[1024];
  37 } GDBProcess;
  38
  39 enum RSState {
  40     RS_INACTIVE,
  41     RS_IDLE,
  42     RS_GETLINE,
  43     RS_GETLINE_ESC,
  44     RS_GETLINE_RLE,
  45     RS_CHKSUM1,
  46     RS_CHKSUM2,
  47 };
  48
  49 typedef struct GDBState {
  50     bool init;       /* have we been initialised? */
  51     CPUState *c_cpu; /* current CPU for step/continue ops */
  52     CPUState *g_cpu; /* current CPU for other ops */
  53     CPUState *query_cpu; /* for q{f|s}ThreadInfo */
  54     enum RSState state; /* parsing state */
  55     char line_buf[MAX_PACKET_LENGTH];
  56     int line_buf_index;
  57     int line_sum; /* running checksum */
  58     int line_csum; /* checksum at the end of the packet */
  59     GByteArray *last_packet;
  60     int signal;
  61     bool multiprocess;
  62     GDBProcess *processes;
  63     int process_num;
  64     GString *str_buf;
  65     GByteArray *mem_buf;
  66     int sstep_flags;
  67     int supported_sstep_flags;
  68 } GDBState;
  69
  70 /* lives in main gdbstub.c */
  71 extern GDBState gdbserver_state;
  72
  73 /*
  74  * Inline utility function, convert from int to hex and back
  75  */
  76
  77 static inline int fromhex(int v)
  78 {
  79     if (v >= '0' && v <= '9') {
  80         return v - '0';
  81     } else if (v >= 'A' && v <= 'F') {
  82         return v - 'A' + 10;
  83     } else if (v >= 'a' && v <= 'f') {
  84         return v - 'a' + 10;
  85     } else {
  86         return 0;
  87     }
  88 }
  89
  90 static inline int tohex(int v)
  91 {
  92     if (v < 10) {
  93         return v + '0';
  94     } else {
  95         return v - 10 + 'a';
  96     }
  97 }
  98
  99 /*
 100  * Connection helpers for both softmmu and user backends
 101  */
 102
 103 void gdb_put_strbuf(void);
 104 int gdb_put_packet(const char *buf);
 105 int gdb_put_packet_binary(const char *buf, int len, bool dump);
 106 void gdb_hextomem(GByteArray *mem, const char *buf, int len);
 107 void gdb_memtohex(GString *buf, const uint8_t *mem, int len);
 108 void gdb_memtox(GString *buf, const char *mem, int len);
 109 void gdb_read_byte(uint8_t ch);
 110
 111 /*
 112  * Packet acknowledgement - we handle this slightly differently
 113  * between user and softmmu mode, mainly to deal with the differences
 114  * between the flexible chardev and the direct fd approaches.
 115  *
 116  * We currently don't support a negotiated QStartNoAckMode
 117  */
 118
 119 /**
 120  * gdb_got_immediate_ack() - check ok to continue
 121  *
 122  * Returns true to continue, false to re-transmit for user only, the
 123  * softmmu stub always returns true.
 124  */
 125 bool gdb_got_immediate_ack(void);
 126 /* utility helpers */
 127 CPUState *gdb_first_attached_cpu(void);
 128 void gdb_append_thread_id(CPUState *cpu, GString *buf);
 129 int gdb_get_cpu_index(CPUState *cpu);
 130 unsigned int gdb_get_max_cpus(void); /* both */
 131 bool gdb_can_reverse(void); /* softmmu, stub for user */
 132
 133 void gdb_create_default_process(GDBState *s);
 134
 135 /* signal mapping, common for softmmu, specialised for user-mode */
 136 int gdb_signal_to_target(int sig);
 137 int gdb_target_signal_to_gdb(int sig);
 138
 139 int gdb_get_char(void); /* user only */
 140
 141 /**
 142  * gdb_continue() - handle continue in mode specific way.
 143  */
 144 void gdb_continue(void);
 145
 146 /**
 147  * gdb_continue_partial() - handle partial continue in mode specific way.
 148  */
 149 int gdb_continue_partial(char *newstates);
 150
 151 /*
 152  * Helpers with separate softmmu and user implementations
 153  */
 154 void gdb_put_buffer(const uint8_t *buf, int len);
 155
 156 /*
 157  * Command handlers - either specialised or softmmu or user only
 158  */
 159 void gdb_init_gdbserver_state(void);
 160
 161 typedef enum GDBThreadIdKind {
 162     GDB_ONE_THREAD = 0,
 163     GDB_ALL_THREADS,     /* One process, all threads */
 164     GDB_ALL_PROCESSES,
 165     GDB_READ_THREAD_ERR
 166 } GDBThreadIdKind;
 167
 168 typedef union GdbCmdVariant {
 169     const char *data;
 170     uint8_t opcode;
 171     unsigned long val_ul;
 172     unsigned long long val_ull;
 173     struct {
 174         GDBThreadIdKind kind;
 175         uint32_t pid;
 176         uint32_t tid;
 177     } thread_id;
 178 } GdbCmdVariant;
 179
 180 #define get_param(p, i)    (&g_array_index(p, GdbCmdVariant, i))
 181
 182 void gdb_handle_query_rcmd(GArray *params, void *user_ctx); /* softmmu */
 183 void gdb_handle_query_offsets(GArray *params, void *user_ctx); /* user */
 184 void gdb_handle_query_xfer_auxv(GArray *params, void *user_ctx); /*user */
 185
 186 void gdb_handle_query_attached(GArray *params, void *user_ctx); /* both */
 187
 188 /* softmmu only */
 189 void gdb_handle_query_qemu_phy_mem_mode(GArray *params, void *user_ctx);
 190 void gdb_handle_set_qemu_phy_mem_mode(GArray *params, void *user_ctx);
 191
 192 /* sycall handling */
 193 void gdb_handle_file_io(GArray *params, void *user_ctx);
 194 bool gdb_handled_syscall(void);
 195 void gdb_disable_syscalls(void);
 196 void gdb_syscall_reset(void);
 197
 198 /* user/softmmu specific syscall handling */
 199 void gdb_syscall_handling(const char *syscall_packet);
 200
 201 /*
 202  * Break/Watch point support - there is an implementation for softmmu
 203  * and user mode.
 204  */
 205 bool gdb_supports_guest_debug(void);
 206 int gdb_breakpoint_insert(CPUState *cs, int type, vaddr addr, vaddr len);
 207 int gdb_breakpoint_remove(CPUState *cs, int type, vaddr addr, vaddr len);
 208 void gdb_breakpoint_remove_all(CPUState *cs);
 209
 210 /**
 211  * gdb_target_memory_rw_debug() - handle debug access to memory
 212  * @cs: CPUState
 213  * @addr: nominal address, could be an entire physical address
 214  * @buf: data
 215  * @len: length of access
 216  * @is_write: is it a write operation
 217  *
 218  * This function is specialised depending on the mode we are running
 219  * in. For softmmu guests we can switch the interpretation of the
 220  * address to a physical address.
 221  */
 222 int gdb_target_memory_rw_debug(CPUState *cs, hwaddr addr,
 223                                uint8_t *buf, int len, bool is_write);
 224
 225 #endif /* GDBSTUB_INTERNALS_H */