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     char *target_xml;
  36 } GDBProcess;
  37
  38 enum RSState {
  39     RS_INACTIVE,
  40     RS_IDLE,
  41     RS_GETLINE,
  42     RS_GETLINE_ESC,
  43     RS_GETLINE_RLE,
  44     RS_CHKSUM1,
  45     RS_CHKSUM2,
  46 };
  47
  48 typedef struct GDBState {
  49     bool init;       /* have we been initialised? */
  50     CPUState *c_cpu; /* current CPU for step/continue ops */
  51     CPUState *g_cpu; /* current CPU for other ops */
  52     CPUState *query_cpu; /* for q{f|s}ThreadInfo */
  53     enum RSState state; /* parsing state */
  54     char line_buf[MAX_PACKET_LENGTH];
  55     int line_buf_index;
  56     int line_sum; /* running checksum */
  57     int line_csum; /* checksum at the end of the packet */
  58     GByteArray *last_packet;
  59     int signal;
  60     bool multiprocess;
  61     GDBProcess *processes;
  62     int process_num;
  63     GString *str_buf;
  64     GByteArray *mem_buf;
  65     int sstep_flags;
  66     int supported_sstep_flags;
  67     /*
  68      * Whether we are allowed to send a stop reply packet at this moment.
  69      * Must be set off after sending the stop reply itself.
  70      */
  71     bool allow_stop_reply;
  72 } GDBState;
  73
  74 /* lives in main gdbstub.c */
  75 extern GDBState gdbserver_state;
  76
  77 /*
  78  * Inline utility function, convert from int to hex and back
  79  */
  80
  81 static inline int fromhex(int v)
  82 {
  83     if (v >= '0' && v <= '9') {
  84         return v - '0';
  85     } else if (v >= 'A' && v <= 'F') {
  86         return v - 'A' + 10;
  87     } else if (v >= 'a' && v <= 'f') {
  88         return v - 'a' + 10;
  89     } else {
  90         return 0;
  91     }
  92 }
  93
  94 static inline int tohex(int v)
  95 {
  96     if (v < 10) {
  97         return v + '0';
  98     } else {
  99         return v - 10 + 'a';
 100     }
 101 }
 102
 103 /*
 104  * Connection helpers for both system and user backends
 105  */
 106
 107 void gdb_put_strbuf(void);
 108 int gdb_put_packet(const char *buf);
 109 int gdb_put_packet_binary(const char *buf, int len, bool dump);
 110 void gdb_hextomem(GByteArray *mem, const char *buf, int len);
 111 void gdb_memtohex(GString *buf, const uint8_t *mem, int len);
 112 void gdb_memtox(GString *buf, const char *mem, int len);
 113 void gdb_read_byte(uint8_t ch);
 114
 115 /*
 116  * Packet acknowledgement - we handle this slightly differently
 117  * between user and softmmu mode, mainly to deal with the differences
 118  * between the flexible chardev and the direct fd approaches.
 119  *
 120  * We currently don't support a negotiated QStartNoAckMode
 121  */
 122
 123 /**
 124  * gdb_got_immediate_ack() - check ok to continue
 125  *
 126  * Returns true to continue, false to re-transmit for user only, the
 127  * softmmu stub always returns true.
 128  */
 129 bool gdb_got_immediate_ack(void);
 130 /* utility helpers */
 131 GDBProcess *gdb_get_process(uint32_t pid);
 132 CPUState *gdb_get_first_cpu_in_process(GDBProcess *process);
 133 CPUState *gdb_first_attached_cpu(void);
 134 void gdb_append_thread_id(CPUState *cpu, GString *buf);
 135 int gdb_get_cpu_index(CPUState *cpu);
 136 unsigned int gdb_get_max_cpus(void); /* both */
 137 bool gdb_can_reverse(void); /* softmmu, stub for user */
 138
 139 void gdb_create_default_process(GDBState *s);
 140
 141 /* signal mapping, common for softmmu, specialised for user-mode */
 142 int gdb_signal_to_target(int sig);
 143 int gdb_target_signal_to_gdb(int sig);
 144
 145 int gdb_get_char(void); /* user only */
 146
 147 /**
 148  * gdb_continue() - handle continue in mode specific way.
 149  */
 150 void gdb_continue(void);
 151
 152 /**
 153  * gdb_continue_partial() - handle partial continue in mode specific way.
 154  */
 155 int gdb_continue_partial(char *newstates);
 156
 157 /*
 158  * Helpers with separate softmmu and user implementations
 159  */
 160 void gdb_put_buffer(const uint8_t *buf, int len);
 161
 162 /*
 163  * Command handlers - either specialised or softmmu or user only
 164  */
 165 void gdb_init_gdbserver_state(void);
 166
 167 typedef enum GDBThreadIdKind {
 168     GDB_ONE_THREAD = 0,
 169     GDB_ALL_THREADS,     /* One process, all threads */
 170     GDB_ALL_PROCESSES,
 171     GDB_READ_THREAD_ERR
 172 } GDBThreadIdKind;
 173
 174 typedef union GdbCmdVariant {
 175     const char *data;
 176     uint8_t opcode;
 177     unsigned long val_ul;
 178     unsigned long long val_ull;
 179     struct {
 180         GDBThreadIdKind kind;
 181         uint32_t pid;
 182         uint32_t tid;
 183     } thread_id;
 184 } GdbCmdVariant;
 185
 186 #define get_param(p, i)    (&g_array_index(p, GdbCmdVariant, i))
 187
 188 void gdb_handle_query_rcmd(GArray *params, void *user_ctx); /* softmmu */
 189 void gdb_handle_query_offsets(GArray *params, void *user_ctx); /* user */
 190 void gdb_handle_query_xfer_auxv(GArray *params, void *user_ctx); /*user */
 191 void gdb_handle_v_file_open(GArray *params, void *user_ctx); /* user */
 192 void gdb_handle_v_file_close(GArray *params, void *user_ctx); /* user */
 193 void gdb_handle_v_file_pread(GArray *params, void *user_ctx); /* user */
 194 void gdb_handle_v_file_readlink(GArray *params, void *user_ctx); /* user */
 195 void gdb_handle_query_xfer_exec_file(GArray *params, void *user_ctx); /* user */
 196
 197 void gdb_handle_query_attached(GArray *params, void *user_ctx); /* both */
 198
 199 /* softmmu only */
 200 void gdb_handle_query_qemu_phy_mem_mode(GArray *params, void *user_ctx);
 201 void gdb_handle_set_qemu_phy_mem_mode(GArray *params, void *user_ctx);
 202
 203 /* sycall handling */
 204 void gdb_handle_file_io(GArray *params, void *user_ctx);
 205 bool gdb_handled_syscall(void);
 206 void gdb_disable_syscalls(void);
 207 void gdb_syscall_reset(void);
 208
 209 /* user/softmmu specific syscall handling */
 210 void gdb_syscall_handling(const char *syscall_packet);
 211
 212 /*
 213  * Break/Watch point support - there is an implementation for softmmu
 214  * and user mode.
 215  */
 216 bool gdb_supports_guest_debug(void);
 217 int gdb_breakpoint_insert(CPUState *cs, int type, vaddr addr, vaddr len);
 218 int gdb_breakpoint_remove(CPUState *cs, int type, vaddr addr, vaddr len);
 219 void gdb_breakpoint_remove_all(CPUState *cs);
 220
 221 /**
 222  * gdb_target_memory_rw_debug() - handle debug access to memory
 223  * @cs: CPUState
 224  * @addr: nominal address, could be an entire physical address
 225  * @buf: data
 226  * @len: length of access
 227  * @is_write: is it a write operation
 228  *
 229  * This function is specialised depending on the mode we are running
 230  * in. For system guests we can switch the interpretation of the
 231  * address to a physical address.
 232  */
 233 int gdb_target_memory_rw_debug(CPUState *cs, hwaddr addr,
 234                                uint8_t *buf, int len, bool is_write);
 235
 236 #endif /* GDBSTUB_INTERNALS_H */