LXR qemu/contrib/plugins/drcov.c

   1/*
   2 * Copyright (C) 2021, Ivanov Arkady <arkadiy.ivanov@ispras.ru>
   3 *
   4 * Drcov - a DynamoRIO-based tool that collects coverage information
   5 * from a binary. Primary goal this script is to have coverage log
   6 * files that work in Lighthouse.
   7 *
   8 * License: GNU GPL, version 2 or later.
   9 *   See the COPYING file in the top-level directory.
  10 */
  11
  12#include <inttypes.h>
  13#include <assert.h>
  14#include <stdlib.h>
  15#include <inttypes.h>
  16#include <string.h>
  17#include <unistd.h>
  18#include <stdio.h>
  19#include <glib.h>
  20
  21#include <qemu-plugin.h>
  22
  23QEMU_PLUGIN_EXPORT int qemu_plugin_version = QEMU_PLUGIN_VERSION;
  24
  25static char header[] = "DRCOV VERSION: 2\n"
  26                "DRCOV FLAVOR: drcov-64\n"
  27                "Module Table: version 2, count 1\n"
  28                "Columns: id, base, end, entry, path\n";
  29
  30static FILE *fp;
  31static const char *file_name = "file.drcov.trace";
  32static GMutex lock;
  33
  34typedef struct {
  35    uint32_t start;
  36    uint16_t size;
  37    uint16_t mod_id;
  38    bool     exec;
  39} bb_entry_t;
  40
  41/* Translated blocks */
  42static GPtrArray *blocks;
  43
  44static void printf_header(unsigned long count)
  45{
  46    fprintf(fp, "%s", header);
  47    const char *path = qemu_plugin_path_to_binary();
  48    uint64_t start_code = qemu_plugin_start_code();
  49    uint64_t end_code = qemu_plugin_end_code();
  50    uint64_t entry = qemu_plugin_entry_code();
  51    fprintf(fp, "0, 0x%lx, 0x%lx, 0x%lx, %s\n",
  52            start_code, end_code, entry, path);
  53    fprintf(fp, "BB Table: %ld bbs\n", count);
  54}
  55
  56static void printf_char_array32(uint32_t data)
  57{
  58    const uint8_t *bytes = (const uint8_t *)(&data);
  59    fwrite(bytes, sizeof(char), sizeof(data), fp);
  60}
  61
  62static void printf_char_array16(uint16_t data)
  63{
  64    const uint8_t *bytes = (const uint8_t *)(&data);
  65    fwrite(bytes, sizeof(char), sizeof(data), fp);
  66}
  67
  68
  69static void printf_el(gpointer data, gpointer user_data)
  70{
  71    bb_entry_t *bb = (bb_entry_t *)data;
  72    if (bb->exec) {
  73        printf_char_array32(bb->start);
  74        printf_char_array16(bb->size);
  75        printf_char_array16(bb->mod_id);
  76    }
  77    g_free(bb);
  78}
  79
  80static void count_block(gpointer data, gpointer user_data)
  81{
  82    unsigned long *count = (unsigned long *) user_data;
  83    bb_entry_t *bb = (bb_entry_t *)data;
  84    if (bb->exec) {
  85        *count = *count + 1;
  86    }
  87}
  88
  89static void plugin_exit(qemu_plugin_id_t id, void *p)
  90{
  91    unsigned long count = 0;
  92    g_mutex_lock(&lock);
  93    g_ptr_array_foreach(blocks, count_block, &count);
  94
  95    /* Print function */
  96    printf_header(count);
  97    g_ptr_array_foreach(blocks, printf_el, NULL);
  98
  99    /* Clear */
 100    g_ptr_array_free(blocks, true);
 101
 102    fclose(fp);
 103
 104    g_mutex_unlock(&lock);
 105}
 106
 107static void plugin_init(void)
 108{
 109    fp = fopen(file_name, "wb");
 110    blocks = g_ptr_array_sized_new(128);
 111}
 112
 113static void vcpu_tb_exec(unsigned int cpu_index, void *udata)
 114{
 115    bb_entry_t *bb = (bb_entry_t *) udata;
 116
 117    g_mutex_lock(&lock);
 118    bb->exec = true;
 119    g_mutex_unlock(&lock);
 120}
 121
 122static void vcpu_tb_trans(qemu_plugin_id_t id, struct qemu_plugin_tb *tb)
 123{
 124    uint64_t pc = qemu_plugin_tb_vaddr(tb);
 125    size_t n = qemu_plugin_tb_n_insns(tb);
 126
 127    g_mutex_lock(&lock);
 128
 129    bb_entry_t *bb = g_new0(bb_entry_t, 1);
 130    for (int i = 0; i < n; i++) {
 131        bb->size += qemu_plugin_insn_size(qemu_plugin_tb_get_insn(tb, i));
 132    }
 133
 134    bb->start = pc;
 135    bb->mod_id = 0;
 136    bb->exec = false;
 137    g_ptr_array_add(blocks, bb);
 138
 139    g_mutex_unlock(&lock);
 140    qemu_plugin_register_vcpu_tb_exec_cb(tb, vcpu_tb_exec,
 141                                         QEMU_PLUGIN_CB_NO_REGS,
 142                                         (void *)bb);
 143
 144}
 145
 146QEMU_PLUGIN_EXPORT
 147int qemu_plugin_install(qemu_plugin_id_t id, const qemu_info_t *info,
 148                        int argc, char **argv)
 149{
 150    for (int i = 0; i < argc; i++) {
 151        g_autofree char **tokens = g_strsplit(argv[i], "=", 2);
 152        if (g_strcmp0(tokens[0], "filename") == 0) {
 153            file_name = g_strdup(tokens[1]);
 154        }
 155    }
 156
 157    plugin_init();
 158
 159    qemu_plugin_register_vcpu_tb_trans_cb(id, vcpu_tb_trans);
 160    qemu_plugin_register_atexit_cb(id, plugin_exit, NULL);
 161
 162    return 0;
 163}
 164