drivers/s390/block/dasd_proc.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   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  * Coypright IBM Corp. 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/slab.h>
  18 #include <linux/string.h>
  19 #include <linux/seq_file.h>
  20 #include <linux/vmalloc.h>
  21 #include <linux/proc_fs.h>
  22
  23 #include <asm/debug.h>
  24 #include <linux/uaccess.h>
  25
  26 /* This is ugly... */
  27 #define PRINTK_HEADER "dasd_proc:"
  28
  29 #include "dasd_int.h"
  30
  31 static struct proc_dir_entry *dasd_proc_root_entry = NULL;
  32 static struct proc_dir_entry *dasd_devices_entry = NULL;
  33 static struct proc_dir_entry *dasd_statistics_entry = NULL;
  34
  35 static int
  36 dasd_devices_show(struct seq_file *m, void *v)
  37 {
  38         struct dasd_device *device;
  39         struct dasd_block *block;
  40         char *substr;
  41
  42         device = dasd_device_from_devindex((unsigned long) v - 1);
  43         if (IS_ERR(device))
  44                 return 0;
  45         if (device->block)
  46                 block = device->block;
  47         else {
  48                 dasd_put_device(device);
  49                 return 0;
  50         }
  51         /* Print device number. */
  52         seq_printf(m, "%s", dev_name(&device->cdev->dev));
  53         /* Print discipline string. */
  54         if (device->discipline != NULL)
  55                 seq_printf(m, "(%s)", device->discipline->name);
  56         else
  57                 seq_printf(m, "(none)");
  58         /* Print kdev. */
  59         if (block->gdp)
  60                 seq_printf(m, " at (%3d:%6d)",
  61                            MAJOR(disk_devt(block->gdp)),
  62                            MINOR(disk_devt(block->gdp)));
  63         else
  64                 seq_printf(m, "  at (???:??????)");
  65         /* Print device name. */
  66         if (block->gdp)
  67                 seq_printf(m, " is %-8s", block->gdp->disk_name);
  68         else
  69                 seq_printf(m, " is ????????");
  70         /* Print devices features. */
  71         substr = (device->features & DASD_FEATURE_READONLY) ? "(ro)" : " ";
  72         seq_printf(m, "%4s: ", substr);
  73         /* Print device status information. */
  74         switch (device->state) {
  75         case DASD_STATE_NEW:
  76                 seq_printf(m, "new");
  77                 break;
  78         case DASD_STATE_KNOWN:
  79                 seq_printf(m, "detected");
  80                 break;
  81         case DASD_STATE_BASIC:
  82                 seq_printf(m, "basic");
  83                 break;
  84         case DASD_STATE_UNFMT:
  85                 seq_printf(m, "unformatted");
  86                 break;
  87         case DASD_STATE_READY:
  88         case DASD_STATE_ONLINE:
  89                 seq_printf(m, "active ");
  90                 if (dasd_check_blocksize(block->bp_block))
  91                         seq_printf(m, "n/f       ");
  92                 else
  93                         seq_printf(m,
  94                                    "at blocksize: %u, %lu blocks, %lu MB",
  95                                    block->bp_block, block->blocks,
  96                                    ((block->bp_block >> 9) *
  97                                     block->blocks) >> 11);
  98                 break;
  99         default:
 100                 seq_printf(m, "no stat");
 101                 break;
 102         }
 103         dasd_put_device(device);
 104         if (dasd_probeonly)
 105                 seq_printf(m, "(probeonly)");
 106         seq_printf(m, "\n");
 107         return 0;
 108 }
 109
 110 static void *dasd_devices_start(struct seq_file *m, loff_t *pos)
 111 {
 112         if (*pos >= dasd_max_devindex)
 113                 return NULL;
 114         return (void *)((unsigned long) *pos + 1);
 115 }
 116
 117 static void *dasd_devices_next(struct seq_file *m, void *v, loff_t *pos)
 118 {
 119         ++*pos;
 120         return dasd_devices_start(m, pos);
 121 }
 122
 123 static void dasd_devices_stop(struct seq_file *m, void *v)
 124 {
 125 }
 126
 127 static const struct seq_operations dasd_devices_seq_ops = {
 128         .start          = dasd_devices_start,
 129         .next           = dasd_devices_next,
 130         .stop           = dasd_devices_stop,
 131         .show           = dasd_devices_show,
 132 };
 133
 134 static int dasd_devices_open(struct inode *inode, struct file *file)
 135 {
 136         return seq_open(file, &dasd_devices_seq_ops);
 137 }
 138
 139 static const struct file_operations dasd_devices_file_ops = {
 140         .owner          = THIS_MODULE,
 141         .open           = dasd_devices_open,
 142         .read           = seq_read,
 143         .llseek         = seq_lseek,
 144         .release        = seq_release,
 145 };
 146
 147 #ifdef CONFIG_DASD_PROFILE
 148 static int dasd_stats_all_block_on(void)
 149 {
 150         int i, rc;
 151         struct dasd_device *device;
 152
 153         rc = 0;
 154         for (i = 0; i < dasd_max_devindex; ++i) {
 155                 device = dasd_device_from_devindex(i);
 156                 if (IS_ERR(device))
 157                         continue;
 158                 if (device->block)
 159                         rc = dasd_profile_on(&device->block->profile);
 160                 dasd_put_device(device);
 161                 if (rc)
 162                         return rc;
 163         }
 164         return 0;
 165 }
 166
 167 static void dasd_stats_all_block_off(void)
 168 {
 169         int i;
 170         struct dasd_device *device;
 171
 172         for (i = 0; i < dasd_max_devindex; ++i) {
 173                 device = dasd_device_from_devindex(i);
 174                 if (IS_ERR(device))
 175                         continue;
 176                 if (device->block)
 177                         dasd_profile_off(&device->block->profile);
 178                 dasd_put_device(device);
 179         }
 180 }
 181
 182 static void dasd_stats_all_block_reset(void)
 183 {
 184         int i;
 185         struct dasd_device *device;
 186
 187         for (i = 0; i < dasd_max_devindex; ++i) {
 188                 device = dasd_device_from_devindex(i);
 189                 if (IS_ERR(device))
 190                         continue;
 191                 if (device->block)
 192                         dasd_profile_reset(&device->block->profile);
 193                 dasd_put_device(device);
 194         }
 195 }
 196
 197 static void dasd_statistics_array(struct seq_file *m, unsigned int *array, int factor)
 198 {
 199         int i;
 200
 201         for (i = 0; i < 32; i++) {
 202                 seq_printf(m, "%7d ", array[i] / factor);
 203                 if (i == 15)
 204                         seq_putc(m, '\n');
 205         }
 206         seq_putc(m, '\n');
 207 }
 208 #endif /* CONFIG_DASD_PROFILE */
 209
 210 static int dasd_stats_proc_show(struct seq_file *m, void *v)
 211 {
 212 #ifdef CONFIG_DASD_PROFILE
 213         struct dasd_profile_info *prof;
 214         int factor;
 215
 216         spin_lock_bh(&dasd_global_profile.lock);
 217         prof = dasd_global_profile.data;
 218         if (!prof) {
 219                 spin_unlock_bh(&dasd_global_profile.lock);
 220                 seq_printf(m, "Statistics are off - they might be "
 221                                     "switched on using 'echo set on > "
 222                                     "/proc/dasd/statistics'\n");
 223                 return 0;
 224         }
 225
 226         /* prevent counter 'overflow' on output */
 227         for (factor = 1; (prof->dasd_io_reqs / factor) > 9999999;
 228              factor *= 10);
 229
 230         seq_printf(m, "%d dasd I/O requests\n", prof->dasd_io_reqs);
 231         seq_printf(m, "with %u sectors(512B each)\n",
 232                        prof->dasd_io_sects);
 233         seq_printf(m, "Scale Factor is  %d\n", factor);
 234         seq_printf(m,
 235                        "   __<4    ___8    __16    __32    __64    _128 "
 236                        "   _256    _512    __1k    __2k    __4k    __8k "
 237                        "   _16k    _32k    _64k    128k\n");
 238         seq_printf(m,
 239                        "   _256    _512    __1M    __2M    __4M    __8M "
 240                        "   _16M    _32M    _64M    128M    256M    512M "
 241                        "   __1G    __2G    __4G " "   _>4G\n");
 242
 243         seq_printf(m, "Histogram of sizes (512B secs)\n");
 244         dasd_statistics_array(m, prof->dasd_io_secs, factor);
 245         seq_printf(m, "Histogram of I/O times (microseconds)\n");
 246         dasd_statistics_array(m, prof->dasd_io_times, factor);
 247         seq_printf(m, "Histogram of I/O times per sector\n");
 248         dasd_statistics_array(m, prof->dasd_io_timps, factor);
 249         seq_printf(m, "Histogram of I/O time till ssch\n");
 250         dasd_statistics_array(m, prof->dasd_io_time1, factor);
 251         seq_printf(m, "Histogram of I/O time between ssch and irq\n");
 252         dasd_statistics_array(m, prof->dasd_io_time2, factor);
 253         seq_printf(m, "Histogram of I/O time between ssch "
 254                             "and irq per sector\n");
 255         dasd_statistics_array(m, prof->dasd_io_time2ps, factor);
 256         seq_printf(m, "Histogram of I/O time between irq and end\n");
 257         dasd_statistics_array(m, prof->dasd_io_time3, factor);
 258         seq_printf(m, "# of req in chanq at enqueuing (1..32) \n");
 259         dasd_statistics_array(m, prof->dasd_io_nr_req, factor);
 260         spin_unlock_bh(&dasd_global_profile.lock);
 261 #else
 262         seq_printf(m, "Statistics are not activated in this kernel\n");
 263 #endif
 264         return 0;
 265 }
 266
 267 static int dasd_stats_proc_open(struct inode *inode, struct file *file)
 268 {
 269         return single_open(file, dasd_stats_proc_show, NULL);
 270 }
 271
 272 static ssize_t dasd_stats_proc_write(struct file *file,
 273                 const char __user *user_buf, size_t user_len, loff_t *pos)
 274 {
 275 #ifdef CONFIG_DASD_PROFILE
 276         char *buffer, *str;
 277         int rc;
 278
 279         if (user_len > 65536)
 280                 user_len = 65536;
 281         buffer = dasd_get_user_string(user_buf, user_len);
 282         if (IS_ERR(buffer))
 283                 return PTR_ERR(buffer);
 284
 285         /* check for valid verbs */
 286         str = skip_spaces(buffer);
 287         if (strncmp(str, "set", 3) == 0 && isspace(str[3])) {
 288                 /* 'set xxx' was given */
 289                 str = skip_spaces(str + 4);
 290                 if (strcmp(str, "on") == 0) {
 291                         /* switch on statistics profiling */
 292                         rc = dasd_stats_all_block_on();
 293                         if (rc) {
 294                                 dasd_stats_all_block_off();
 295                                 goto out_error;
 296                         }
 297                         rc = dasd_profile_on(&dasd_global_profile);
 298                         if (rc) {
 299                                 dasd_stats_all_block_off();
 300                                 goto out_error;
 301                         }
 302                         dasd_profile_reset(&dasd_global_profile);
 303                         dasd_global_profile_level = DASD_PROFILE_ON;
 304                         pr_info("The statistics feature has been switched "
 305                                 "on\n");
 306                 } else if (strcmp(str, "off") == 0) {
 307                         /* switch off statistics profiling */
 308                         dasd_global_profile_level = DASD_PROFILE_OFF;
 309                         dasd_profile_off(&dasd_global_profile);
 310                         dasd_stats_all_block_off();
 311                         pr_info("The statistics feature has been switched "
 312                                 "off\n");
 313                 } else
 314                         goto out_parse_error;
 315         } else if (strncmp(str, "reset", 5) == 0) {
 316                 /* reset the statistics */
 317                 dasd_profile_reset(&dasd_global_profile);
 318                 dasd_stats_all_block_reset();
 319                 pr_info("The statistics have been reset\n");
 320         } else
 321                 goto out_parse_error;
 322         vfree(buffer);
 323         return user_len;
 324 out_parse_error:
 325         rc = -EINVAL;
 326         pr_warn("%s is not a supported value for /proc/dasd/statistics\n", str);
 327 out_error:
 328         vfree(buffer);
 329         return rc;
 330 #else
 331         pr_warn("/proc/dasd/statistics: is not activated in this kernel\n");
 332         return user_len;
 333 #endif                          /* CONFIG_DASD_PROFILE */
 334 }
 335
 336 static const struct file_operations dasd_stats_proc_fops = {
 337         .owner          = THIS_MODULE,
 338         .open           = dasd_stats_proc_open,
 339         .read           = seq_read,
 340         .llseek         = seq_lseek,
 341         .release        = single_release,
 342         .write          = dasd_stats_proc_write,
 343 };
 344
 345 /*
 346  * Create dasd proc-fs entries.
 347  * In case creation failed, cleanup and return -ENOENT.
 348  */
 349 int
 350 dasd_proc_init(void)
 351 {
 352         dasd_proc_root_entry = proc_mkdir("dasd", NULL);
 353         if (!dasd_proc_root_entry)
 354                 goto out_nodasd;
 355         dasd_devices_entry = proc_create("devices",
 356                                          S_IFREG | S_IRUGO | S_IWUSR,
 357                                          dasd_proc_root_entry,
 358                                          &dasd_devices_file_ops);
 359         if (!dasd_devices_entry)
 360                 goto out_nodevices;
 361         dasd_statistics_entry = proc_create("statistics",
 362                                             S_IFREG | S_IRUGO | S_IWUSR,
 363                                             dasd_proc_root_entry,
 364                                             &dasd_stats_proc_fops);
 365         if (!dasd_statistics_entry)
 366                 goto out_nostatistics;
 367         return 0;
 368
 369  out_nostatistics:
 370         remove_proc_entry("devices", dasd_proc_root_entry);
 371  out_nodevices:
 372         remove_proc_entry("dasd", NULL);
 373  out_nodasd:
 374         return -ENOENT;
 375 }
 376
 377 void
 378 dasd_proc_exit(void)
 379 {
 380         remove_proc_entry("devices", dasd_proc_root_entry);
 381         remove_proc_entry("statistics", dasd_proc_root_entry);
 382         remove_proc_entry("dasd", NULL);
 383 }