webprobe/webprobe_debugfs.c

   1 /**
   2  *  webprobe/webprobe_debugfs.c
   3  *
   4  * This program is free software; you can redistribute it and/or modify
   5  * it under the terms of the GNU General Public License as published by
   6  * the Free Software Foundation; either version 2 of the License, or
   7  * (at your option) any later version.
   8  *
   9  * This program is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  * GNU General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU General Public License
  15  * along with this program; if not, see <http://www.gnu.org/licenses/>.
  16  *
  17  * Copyright (C) Samsung Electronics, 2015
  18  *
  19  * 2015          Anastasia Lyupa <a.lyupa@samsung.com>
  20  *
  21  */
  22
  23 #include <linux/module.h>
  24 #include <linux/slab.h>
  25 #include <linux/debugfs.h>
  26 #include <linux/uaccess.h>
  27
  28 #include <master/swap_debugfs.h>
  29 #include <master/swap_initializer.h>
  30
  31 #include "webprobe_debugfs.h"
  32 #include "webprobe.h"
  33
  34 static const char ENABLED_FILE[] =              "enabled";
  35 static const char APP_INFO_FILE[] =             "app_info";
  36 static const char INSPSERVER_START_FILE[] =     "inspector_server_start";
  37 static const char TICK_PROBE_FILE[] =           "tick_probe";
  38
  39 enum { max_count = 256 };
  40 static char app_info[max_count];
  41
  42 /* ============================================================================
  43  * ===              DEBUGFS FOR WEBPROBE INSTRUMENTATION                    ===
  44  * ============================================================================
  45  */
  46
  47 static ssize_t read_enabled(struct file *file, char __user *user_buf,
  48                             size_t count, loff_t *ppos)
  49 {
  50         char buf[2];
  51
  52         buf[0] = web_prof_enabled() ? '1' : '0';
  53         buf[1] = '\n';
  54
  55         return simple_read_from_buffer(user_buf, count, ppos, buf, 2);
  56 }
  57
  58 static ssize_t write_enabled(struct file *file, const char __user *user_buf,
  59                              size_t count, loff_t *ppos)
  60 {
  61         int ret = 0;
  62         char buf[32];
  63         size_t buf_size;
  64
  65         buf_size = min(count, (sizeof(buf) - 1));
  66         if (copy_from_user(buf, user_buf, buf_size))
  67                 return -EFAULT;
  68
  69         buf[buf_size] = '\0';
  70         switch (buf[0]) {
  71         case '1':
  72                 ret = web_prof_enable();
  73                 break;
  74         case '0':
  75                 ret = web_prof_disable();
  76                 break;
  77         default:
  78                 return -EINVAL;
  79         }
  80
  81         if (ret)
  82                 return ret;
  83
  84         return count;
  85 }
  86
  87 static const struct file_operations fops_enabled = {
  88         .write =        write_enabled,
  89         .read =         read_enabled,
  90         .open =         swap_init_simple_open,
  91         .release =      swap_init_simple_release,
  92 };
  93
  94 static ssize_t write_app_info(struct file *file, const char __user *user_buf,
  95                               size_t count, loff_t *ppos)
  96 {
  97         int ret = 0;
  98         char *buf, *path, *id;
  99         int n;
 100
 101         if (count > max_count)
 102                 return -ENOMEM;
 103
 104         buf = kmalloc(count + 1, GFP_KERNEL);
 105         if (!buf)
 106                 return -ENOMEM;
 107
 108         if (copy_from_user(buf, user_buf, count)) {
 109                 ret = -EFAULT;
 110                 goto free_buf;
 111         }
 112
 113         buf[count] = '\0';
 114
 115         path = kmalloc(count, GFP_KERNEL);
 116         if (!path) {
 117                 ret = -ENOMEM;
 118                 goto free_buf;
 119         }
 120
 121         id = kmalloc(count, GFP_KERNEL);
 122         if (!id) {
 123                 ret = -ENOMEM;
 124                 goto free_path;
 125         }
 126
 127         n = sscanf(buf, "%s %s", path, id);
 128
 129         if (n != 2) {
 130                 ret = -EINVAL;
 131                 goto free_app_info;
 132         }
 133
 134         web_prof_data_set(path, id);
 135         snprintf(app_info, sizeof(app_info), "%s\n", buf);
 136
 137 free_app_info:
 138         kfree(id);
 139 free_path:
 140         kfree(path);
 141 free_buf:
 142         kfree(buf);
 143
 144         return ret ? ret : count;
 145 }
 146
 147 static ssize_t read_app_info(struct file *file, char __user *userbuf,
 148                              size_t count, loff_t *ppos)
 149 {
 150         return simple_read_from_buffer(userbuf, count, ppos, app_info,
 151                                        sizeof(app_info) - 1);
 152 }
 153
 154 static const struct file_operations fops_app_info = {
 155         .write =        write_app_info,
 156         .read =         read_app_info,
 157         .open =         swap_init_simple_open,
 158         .release =      swap_init_simple_release,
 159 };
 160
 161 /* ============================================================================
 162  * ===                             INIT/EXIT                                ===
 163  * ============================================================================
 164  */
 165
 166 static struct dentry *webprobe_dir;
 167
 168 void webprobe_debugfs_exit(void)
 169 {
 170         debugfs_remove_recursive(webprobe_dir);
 171         webprobe_dir = NULL;
 172 }
 173
 174 int webprobe_debugfs_init(void)
 175 {
 176         struct dentry *dentry;
 177
 178         dentry = swap_debugfs_getdir();
 179         if (!dentry)
 180                 return -ENOENT;
 181
 182         webprobe_dir = debugfs_create_dir("webprobe", dentry);
 183         if (!webprobe_dir)
 184                 return -ENOMEM;
 185
 186         dentry = debugfs_create_file(ENABLED_FILE, 0600, webprobe_dir, NULL,
 187                                      &fops_enabled);
 188
 189         dentry = debugfs_create_file(APP_INFO_FILE, 0600, webprobe_dir,
 190                                      NULL, &fops_app_info);
 191         if (!dentry)
 192                 goto fail;
 193
 194         dentry = debugfs_create_x64(INSPSERVER_START_FILE, 0600, webprobe_dir,
 195                                     web_prof_addr_ptr(INSPSERVER_START));
 196         if (!dentry)
 197                 goto fail;
 198
 199         dentry = debugfs_create_x64(TICK_PROBE_FILE, 0600, webprobe_dir,
 200                                     web_prof_addr_ptr(TICK_PROBE));
 201         if (!dentry)
 202                 goto fail;
 203
 204         return 0;
 205
 206 fail:
 207         webprobe_debugfs_exit();
 208         return -ENOMEM;
 209 }