drivers/s390/block/dasd_proc.c

   1 /*
   2  * File...........: linux/drivers/s390/block/dasd_proc.c
   3  * Author(s)......: Holger Smolinski <Holger.Smolinski@de.ibm.com>
   4  *                  Horst Hummel <Horst.Hummel@de.ibm.com>
   5  *                  Carsten Otte <Cotte@de.ibm.com>
   6  *                  Martin Schwidefsky <schwidefsky@de.ibm.com>
   7  * Bugreports.to..: <Linux390@de.ibm.com>
   8  * (C) IBM Corporation, IBM Deutschland Entwicklung GmbH, 1999-2002
   9  *
  10  * /proc interface for the dasd driver.
  11  *
  12  */
  13
  14 #define KMSG_COMPONENT "dasd"
  15
  16 #include <linux/ctype.h>
  17 #include <linux/seq_file.h>
  18 #include <linux/vmalloc.h>
  19 #include <linux/proc_fs.h>
  20
  21 #include <asm/debug.h>
  22 #include <asm/uaccess.h>
  23
  24 /* This is ugly... */
  25 #define PRINTK_HEADER "dasd_proc:"
  26
  27 #include "dasd_int.h"
  28
  29 static struct proc_dir_entry *dasd_proc_root_entry = NULL;
  30 static struct proc_dir_entry *dasd_devices_entry = NULL;
  31 static struct proc_dir_entry *dasd_statistics_entry = NULL;
  32
  33 #ifdef CONFIG_DASD_PROFILE
  34 static char *
  35 dasd_get_user_string(const char __user *user_buf, size_t user_len)
  36 {
  37         char *buffer;
  38
  39         buffer = kmalloc(user_len + 1, GFP_KERNEL);
  40         if (buffer == NULL)
  41                 return ERR_PTR(-ENOMEM);
  42         if (copy_from_user(buffer, user_buf, user_len) != 0) {
  43                 kfree(buffer);
  44                 return ERR_PTR(-EFAULT);
  45         }
  46         /* got the string, now strip linefeed. */
  47         if (buffer[user_len - 1] == '\n')
  48                 buffer[user_len - 1] = 0;
  49         else
  50                 buffer[user_len] = 0;
  51         return buffer;
  52 }
  53 #endif /* CONFIG_DASD_PROFILE */
  54
  55 static int
  56 dasd_devices_show(struct seq_file *m, void *v)
  57 {
  58         struct dasd_device *device;
  59         struct dasd_block *block;
  60         char *substr;
  61
  62         device = dasd_device_from_devindex((unsigned long) v - 1);
  63         if (IS_ERR(device))
  64                 return 0;
  65         if (device->block)
  66                 block = device->block;
  67         else {
  68                 dasd_put_device(device);
  69                 return 0;
  70         }
  71         /* Print device number. */
  72         seq_printf(m, "%s", dev_name(&device->cdev->dev));
  73         /* Print discipline string. */
  74         if (device != NULL && device->discipline != NULL)
  75                 seq_printf(m, "(%s)", device->discipline->name);
  76         else
  77                 seq_printf(m, "(none)");
  78         /* Print kdev. */
  79         if (block->gdp)
  80                 seq_printf(m, " at (%3d:%6d)",
  81                            MAJOR(disk_devt(block->gdp)),
  82                            MINOR(disk_devt(block->gdp)));
  83         else
  84                 seq_printf(m, "  at (???:??????)");
  85         /* Print device name. */
  86         if (block->gdp)
  87                 seq_printf(m, " is %-8s", block->gdp->disk_name);
  88         else
  89                 seq_printf(m, " is ????????");
  90         /* Print devices features. */
  91         substr = (device->features & DASD_FEATURE_READONLY) ? "(ro)" : " ";
  92         seq_printf(m, "%4s: ", substr);
  93         /* Print device status information. */
  94         switch ((device != NULL) ? device->state : -1) {
  95         case -1:
  96                 seq_printf(m, "unknown");
  97                 break;
  98         case DASD_STATE_NEW:
  99                 seq_printf(m, "new");
 100                 break;
 101         case DASD_STATE_KNOWN:
 102                 seq_printf(m, "detected");
 103                 break;
 104         case DASD_STATE_BASIC:
 105                 seq_printf(m, "basic");
 106                 break;
 107         case DASD_STATE_UNFMT:
 108                 seq_printf(m, "unformatted");
 109                 break;
 110         case DASD_STATE_READY:
 111         case DASD_STATE_ONLINE:
 112                 seq_printf(m, "active ");
 113                 if (dasd_check_blocksize(block->bp_block))
 114                         seq_printf(m, "n/f       ");
 115                 else
 116                         seq_printf(m,
 117                                    "at blocksize: %d, %lld blocks, %lld MB",
 118                                    block->bp_block, block->blocks,
 119                                    ((block->bp_block >> 9) *
 120                                     block->blocks) >> 11);
 121                 break;
 122         default:
 123                 seq_printf(m, "no stat");
 124                 break;
 125         }
 126         dasd_put_device(device);
 127         if (dasd_probeonly)
 128                 seq_printf(m, "(probeonly)");
 129         seq_printf(m, "\n");
 130         return 0;
 131 }
 132
 133 static void *dasd_devices_start(struct seq_file *m, loff_t *pos)
 134 {
 135         if (*pos >= dasd_max_devindex)
 136                 return NULL;
 137         return (void *)((unsigned long) *pos + 1);
 138 }
 139
 140 static void *dasd_devices_next(struct seq_file *m, void *v, loff_t *pos)
 141 {
 142         ++*pos;
 143         return dasd_devices_start(m, pos);
 144 }
 145
 146 static void dasd_devices_stop(struct seq_file *m, void *v)
 147 {
 148 }
 149
 150 static const struct seq_operations dasd_devices_seq_ops = {
 151         .start          = dasd_devices_start,
 152         .next           = dasd_devices_next,
 153         .stop           = dasd_devices_stop,
 154         .show           = dasd_devices_show,
 155 };
 156
 157 static int dasd_devices_open(struct inode *inode, struct file *file)
 158 {
 159         return seq_open(file, &dasd_devices_seq_ops);
 160 }
 161
 162 static const struct file_operations dasd_devices_file_ops = {
 163         .owner          = THIS_MODULE,
 164         .open           = dasd_devices_open,
 165         .read           = seq_read,
 166         .llseek         = seq_lseek,
 167         .release        = seq_release,
 168 };
 169
 170 static int
 171 dasd_calc_metrics(char *page, char **start, off_t off,
 172                   int count, int *eof, int len)
 173 {
 174         len = (len > off) ? len - off : 0;
 175         if (len > count)
 176                 len = count;
 177         if (len < count)
 178                 *eof = 1;
 179         *start = page + off;
 180         return len;
 181 }
 182
 183 #ifdef CONFIG_DASD_PROFILE
 184 static char *
 185 dasd_statistics_array(char *str, unsigned int *array, int factor)
 186 {
 187         int i;
 188
 189         for (i = 0; i < 32; i++) {
 190                 str += sprintf(str, "%7d ", array[i] / factor);
 191                 if (i == 15)
 192                         str += sprintf(str, "\n");
 193         }
 194         str += sprintf(str,"\n");
 195         return str;
 196 }
 197 #endif /* CONFIG_DASD_PROFILE */
 198
 199 static int
 200 dasd_statistics_read(char *page, char **start, off_t off,
 201                      int count, int *eof, void *data)
 202 {
 203         unsigned long len;
 204 #ifdef CONFIG_DASD_PROFILE
 205         struct dasd_profile_info_t *prof;
 206         char *str;
 207         int factor;
 208
 209         /* check for active profiling */
 210         if (dasd_profile_level == DASD_PROFILE_OFF) {
 211                 len = sprintf(page, "Statistics are off - they might be "
 212                                     "switched on using 'echo set on > "
 213                                     "/proc/dasd/statistics'\n");
 214                 return dasd_calc_metrics(page, start, off, count, eof, len);
 215         }
 216
 217         prof = &dasd_global_profile;
 218         /* prevent counter 'overflow' on output */
 219         for (factor = 1; (prof->dasd_io_reqs / factor) > 9999999;
 220              factor *= 10);
 221
 222         str = page;
 223         str += sprintf(str, "%d dasd I/O requests\n", prof->dasd_io_reqs);
 224         str += sprintf(str, "with %u sectors(512B each)\n",
 225                        prof->dasd_io_sects);
 226         str += sprintf(str, "Scale Factor is  %d\n", factor);
 227         str += sprintf(str,
 228                        "   __<4    ___8    __16    __32    __64    _128 "
 229                        "   _256    _512    __1k    __2k    __4k    __8k "
 230                        "   _16k    _32k    _64k    128k\n");
 231         str += sprintf(str,
 232                        "   _256    _512    __1M    __2M    __4M    __8M "
 233                        "   _16M    _32M    _64M    128M    256M    512M "
 234                        "   __1G    __2G    __4G " "   _>4G\n");
 235
 236         str += sprintf(str, "Histogram of sizes (512B secs)\n");
 237         str = dasd_statistics_array(str, prof->dasd_io_secs, factor);
 238         str += sprintf(str, "Histogram of I/O times (microseconds)\n");
 239         str = dasd_statistics_array(str, prof->dasd_io_times, factor);
 240         str += sprintf(str, "Histogram of I/O times per sector\n");
 241         str = dasd_statistics_array(str, prof->dasd_io_timps, factor);
 242         str += sprintf(str, "Histogram of I/O time till ssch\n");
 243         str = dasd_statistics_array(str, prof->dasd_io_time1, factor);
 244         str += sprintf(str, "Histogram of I/O time between ssch and irq\n");
 245         str = dasd_statistics_array(str, prof->dasd_io_time2, factor);
 246         str += sprintf(str, "Histogram of I/O time between ssch "
 247                             "and irq per sector\n");
 248         str = dasd_statistics_array(str, prof->dasd_io_time2ps, factor);
 249         str += sprintf(str, "Histogram of I/O time between irq and end\n");
 250         str = dasd_statistics_array(str, prof->dasd_io_time3, factor);
 251         str += sprintf(str, "# of req in chanq at enqueuing (1..32) \n");
 252         str = dasd_statistics_array(str, prof->dasd_io_nr_req, factor);
 253         len = str - page;
 254 #else
 255         len = sprintf(page, "Statistics are not activated in this kernel\n");
 256 #endif
 257         return dasd_calc_metrics(page, start, off, count, eof, len);
 258 }
 259
 260 static int
 261 dasd_statistics_write(struct file *file, const char __user *user_buf,
 262                       unsigned long user_len, void *data)
 263 {
 264 #ifdef CONFIG_DASD_PROFILE
 265         char *buffer, *str;
 266
 267         if (user_len > 65536)
 268                 user_len = 65536;
 269         buffer = dasd_get_user_string(user_buf, user_len);
 270         if (IS_ERR(buffer))
 271                 return PTR_ERR(buffer);
 272         DBF_EVENT(DBF_DEBUG, "/proc/dasd/statictics: '%s'\n", buffer);
 273
 274         /* check for valid verbs */
 275         for (str = buffer; isspace(*str); str++);
 276         if (strncmp(str, "set", 3) == 0 && isspace(str[3])) {
 277                 /* 'set xxx' was given */
 278                 for (str = str + 4; isspace(*str); str++);
 279                 if (strcmp(str, "on") == 0) {
 280                         /* switch on statistics profiling */
 281                         dasd_profile_level = DASD_PROFILE_ON;
 282                         pr_info("The statistics feature has been switched "
 283                                 "on\n");
 284                 } else if (strcmp(str, "off") == 0) {
 285                         /* switch off and reset statistics profiling */
 286                         memset(&dasd_global_profile,
 287                                0, sizeof (struct dasd_profile_info_t));
 288                         dasd_profile_level = DASD_PROFILE_OFF;
 289                         pr_info("The statistics feature has been switched "
 290                                 "off\n");
 291                 } else
 292                         goto out_error;
 293         } else if (strncmp(str, "reset", 5) == 0) {
 294                 /* reset the statistics */
 295                 memset(&dasd_global_profile, 0,
 296                        sizeof (struct dasd_profile_info_t));
 297                 pr_info("The statistics have been reset\n");
 298         } else
 299                 goto out_error;
 300         kfree(buffer);
 301         return user_len;
 302 out_error:
 303         pr_warning("%s is not a supported value for /proc/dasd/statistics\n",
 304                 str);
 305         kfree(buffer);
 306         return -EINVAL;
 307 #else
 308         pr_warning("/proc/dasd/statistics: is not activated in this kernel\n");
 309         return user_len;
 310 #endif                          /* CONFIG_DASD_PROFILE */
 311 }
 312
 313 /*
 314  * Create dasd proc-fs entries.
 315  * In case creation failed, cleanup and return -ENOENT.
 316  */
 317 int
 318 dasd_proc_init(void)
 319 {
 320         dasd_proc_root_entry = proc_mkdir("dasd", NULL);
 321         if (!dasd_proc_root_entry)
 322                 goto out_nodasd;
 323         dasd_devices_entry = proc_create("devices",
 324                                          S_IFREG | S_IRUGO | S_IWUSR,
 325                                          dasd_proc_root_entry,
 326                                          &dasd_devices_file_ops);
 327         if (!dasd_devices_entry)
 328                 goto out_nodevices;
 329         dasd_statistics_entry = create_proc_entry("statistics",
 330                                                   S_IFREG | S_IRUGO | S_IWUSR,
 331                                                   dasd_proc_root_entry);
 332         if (!dasd_statistics_entry)
 333                 goto out_nostatistics;
 334         dasd_statistics_entry->read_proc = dasd_statistics_read;
 335         dasd_statistics_entry->write_proc = dasd_statistics_write;
 336         return 0;
 337
 338  out_nostatistics:
 339         remove_proc_entry("devices", dasd_proc_root_entry);
 340  out_nodevices:
 341         remove_proc_entry("dasd", NULL);
 342  out_nodasd:
 343         return -ENOENT;
 344 }
 345
 346 void
 347 dasd_proc_exit(void)
 348 {
 349         remove_proc_entry("devices", dasd_proc_root_entry);
 350         remove_proc_entry("statistics", dasd_proc_root_entry);
 351         remove_proc_entry("dasd", NULL);
 352 }