qemu/gdbstub/user-target.c

/*
 * Target specific user-mode handling
 *
 * Copyright (c) 2003-2005 Fabrice Bellard
 * Copyright (c) 2022 Linaro Ltd
 *
 * SPDX-License-Identifier: LGPL-2.0+
 */

#include "qemu/osdep.h"
#include "exec/gdbstub.h"
#include "qemu.h"
#include "internals.h"

/*
 * Map target signal numbers to GDB protocol signal numbers and vice
 * versa.  For user emulation's currently supported systems, we can
 * assume most signals are defined.
 */

static int gdb_signal_table[] = {
    0,
    TARGET_SIGHUP,
    TARGET_SIGINT,
    TARGET_SIGQUIT,
    TARGET_SIGILL,
    TARGET_SIGTRAP,
    TARGET_SIGABRT,
    -1, /* SIGEMT */
    TARGET_SIGFPE,
    TARGET_SIGKILL,
    TARGET_SIGBUS,
    TARGET_SIGSEGV,
    TARGET_SIGSYS,
    TARGET_SIGPIPE,
    TARGET_SIGALRM,
    TARGET_SIGTERM,
    TARGET_SIGURG,
    TARGET_SIGSTOP,
    TARGET_SIGTSTP,
    TARGET_SIGCONT,
    TARGET_SIGCHLD,
    TARGET_SIGTTIN,
    TARGET_SIGTTOU,
    TARGET_SIGIO,
    TARGET_SIGXCPU,
    TARGET_SIGXFSZ,
    TARGET_SIGVTALRM,
    TARGET_SIGPROF,
    TARGET_SIGWINCH,
    -1, /* SIGLOST */
    TARGET_SIGUSR1,
    TARGET_SIGUSR2,
#ifdef TARGET_SIGPWR
    TARGET_SIGPWR,
#else
    -1,
#endif
    -1, /* SIGPOLL */
    -1,
    -1,
    -1,
    -1,
    -1,
    -1,
    -1,
    -1,
    -1,
    -1,
    -1,
#ifdef __SIGRTMIN
    __SIGRTMIN + 1,
    __SIGRTMIN + 2,
    __SIGRTMIN + 3,
    __SIGRTMIN + 4,
    __SIGRTMIN + 5,
    __SIGRTMIN + 6,
    __SIGRTMIN + 7,
    __SIGRTMIN + 8,
    __SIGRTMIN + 9,
    __SIGRTMIN + 10,
    __SIGRTMIN + 11,
    __SIGRTMIN + 12,
    __SIGRTMIN + 13,
    __SIGRTMIN + 14,
    __SIGRTMIN + 15,
    __SIGRTMIN + 16,
    __SIGRTMIN + 17,
    __SIGRTMIN + 18,
    __SIGRTMIN + 19,
    __SIGRTMIN + 20,
    __SIGRTMIN + 21,
    __SIGRTMIN + 22,
    __SIGRTMIN + 23,
    __SIGRTMIN + 24,
    __SIGRTMIN + 25,
    __SIGRTMIN + 26,
    __SIGRTMIN + 27,
    __SIGRTMIN + 28,
    __SIGRTMIN + 29,
    __SIGRTMIN + 30,
    __SIGRTMIN + 31,
    -1, /* SIGCANCEL */
    __SIGRTMIN,
    __SIGRTMIN + 32,
    __SIGRTMIN + 33,
    __SIGRTMIN + 34,
    __SIGRTMIN + 35,
    __SIGRTMIN + 36,
    __SIGRTMIN + 37,
    __SIGRTMIN + 38,
    __SIGRTMIN + 39,
    __SIGRTMIN + 40,
    __SIGRTMIN + 41,
    __SIGRTMIN + 42,
    __SIGRTMIN + 43,
    __SIGRTMIN + 44,
    __SIGRTMIN + 45,
    __SIGRTMIN + 46,
    __SIGRTMIN + 47,
    __SIGRTMIN + 48,
    __SIGRTMIN + 49,
    __SIGRTMIN + 50,
    __SIGRTMIN + 51,
    __SIGRTMIN + 52,
    __SIGRTMIN + 53,
    __SIGRTMIN + 54,
    __SIGRTMIN + 55,
    __SIGRTMIN + 56,
    __SIGRTMIN + 57,
    __SIGRTMIN + 58,
    __SIGRTMIN + 59,
    __SIGRTMIN + 60,
    __SIGRTMIN + 61,
    __SIGRTMIN + 62,
    __SIGRTMIN + 63,
    __SIGRTMIN + 64,
    __SIGRTMIN + 65,
    __SIGRTMIN + 66,
    __SIGRTMIN + 67,
    __SIGRTMIN + 68,
    __SIGRTMIN + 69,
    __SIGRTMIN + 70,
    __SIGRTMIN + 71,
    __SIGRTMIN + 72,
    __SIGRTMIN + 73,
    __SIGRTMIN + 74,
    __SIGRTMIN + 75,
    __SIGRTMIN + 76,
    __SIGRTMIN + 77,
    __SIGRTMIN + 78,
    __SIGRTMIN + 79,
    __SIGRTMIN + 80,
    __SIGRTMIN + 81,
    __SIGRTMIN + 82,
    __SIGRTMIN + 83,
    __SIGRTMIN + 84,
    __SIGRTMIN + 85,
    __SIGRTMIN + 86,
    __SIGRTMIN + 87,
    __SIGRTMIN + 88,
    __SIGRTMIN + 89,
    __SIGRTMIN + 90,
    __SIGRTMIN + 91,
    __SIGRTMIN + 92,
    __SIGRTMIN + 93,
    __SIGRTMIN + 94,
    __SIGRTMIN + 95,
    -1, /* SIGINFO */
    -1, /* UNKNOWN */
    -1, /* DEFAULT */
    -1,
    -1,
    -1,
    -1,
    -1,
    -1
#endif
};

int gdb_signal_to_target(int sig)
{
    if (sig < ARRAY_SIZE(gdb_signal_table)) {
        return gdb_signal_table[sig];
    } else {
        return -1;
    }
}

int gdb_target_signal_to_gdb(int sig)
{
    int i;
    for (i = 0; i < ARRAY_SIZE(gdb_signal_table); i++) {
        if (gdb_signal_table[i] == sig) {
            return i;
        }
    }
    return GDB_SIGNAL_UNKNOWN;
}

int gdb_get_cpu_index(CPUState *cpu)
{
    TaskState *ts = (TaskState *) cpu->opaque;
    return ts ? ts->ts_tid : -1;
}

/*
 * User-mode specific command helpers
 */

void gdb_handle_query_offsets(GArray *params, void *user_ctx)
{
    TaskState *ts;

    ts = gdbserver_state.c_cpu->opaque;
    g_string_printf(gdbserver_state.str_buf,
                    "Text=" TARGET_ABI_FMT_lx
                    ";Data=" TARGET_ABI_FMT_lx
                    ";Bss=" TARGET_ABI_FMT_lx,
                    ts->info->code_offset,
                    ts->info->data_offset,
                    ts->info->data_offset);
    gdb_put_strbuf();
}

#if defined(CONFIG_LINUX)
/* Partial user only duplicate of helper in gdbstub.c */
static inline int target_memory_rw_debug(CPUState *cpu, target_ulong addr,
                                         uint8_t *buf, int len, bool is_write)
{
    CPUClass *cc;
    cc = CPU_GET_CLASS(cpu);
    if (cc->memory_rw_debug) {
        return cc->memory_rw_debug(cpu, addr, buf, len, is_write);
    }
    return cpu_memory_rw_debug(cpu, addr, buf, len, is_write);
}

void gdb_handle_query_xfer_auxv(GArray *params, void *user_ctx)
{
    TaskState *ts;
    unsigned long offset, len, saved_auxv, auxv_len;

    if (params->len < 2) {
        gdb_put_packet("E22");
        return;
    }

    offset = get_param(params, 0)->val_ul;
    len = get_param(params, 1)->val_ul;
    ts = gdbserver_state.c_cpu->opaque;
    saved_auxv = ts->info->saved_auxv;
    auxv_len = ts->info->auxv_len;

    if (offset >= auxv_len) {
        gdb_put_packet("E00");
        return;
    }

    if (len > (MAX_PACKET_LENGTH - 5) / 2) {
        len = (MAX_PACKET_LENGTH - 5) / 2;
    }

    if (len < auxv_len - offset) {
        g_string_assign(gdbserver_state.str_buf, "m");
    } else {
        g_string_assign(gdbserver_state.str_buf, "l");
        len = auxv_len - offset;
    }

    g_byte_array_set_size(gdbserver_state.mem_buf, len);
    if (target_memory_rw_debug(gdbserver_state.g_cpu, saved_auxv + offset,
                               gdbserver_state.mem_buf->data, len, false)) {
        gdb_put_packet("E14");
        return;
    }

    gdb_memtox(gdbserver_state.str_buf,
           (const char *)gdbserver_state.mem_buf->data, len);
    gdb_put_packet_binary(gdbserver_state.str_buf->str,
                      gdbserver_state.str_buf->len, true);
}
#endif