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  * Copyright IBM Corp. 1999, 2002
   9  *
  10  * /proc interface for the dasd driver.
  11  *
  12  */
  13
  14 #include <linux/ctype.h>
  15 #include <linux/slab.h>
  16 #include <linux/string.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 <linux/uaccess.h>
  23
  24 #include "dasd_int.h"
  25
  26 static struct proc_dir_entry *dasd_proc_root_entry = NULL;
  27 static struct proc_dir_entry *dasd_devices_entry = NULL;
  28 static struct proc_dir_entry *dasd_statistics_entry = NULL;
  29
  30 static int
  31 dasd_devices_show(struct seq_file *m, void *v)
  32 {
  33         struct dasd_device *device;
  34         struct dasd_block *block;
  35         char *substr;
  36
  37         device = dasd_device_from_devindex((unsigned long) v - 1);
  38         if (IS_ERR(device))
  39                 return 0;
  40         if (device->block)
  41                 block = device->block;
  42         else {
  43                 dasd_put_device(device);
  44                 return 0;
  45         }
  46         /* Print device number. */
  47         seq_printf(m, "%s", dev_name(&device->cdev->dev));
  48         /* Print discipline string. */
  49         if (device->discipline != NULL)
  50                 seq_printf(m, "(%s)", device->discipline->name);
  51         else
  52                 seq_printf(m, "(none)");
  53         /* Print kdev. */
  54         if (block->gdp)
  55                 seq_printf(m, " at (%3d:%6d)",
  56                            MAJOR(disk_devt(block->gdp)),
  57                            MINOR(disk_devt(block->gdp)));
  58         else
  59                 seq_printf(m, "  at (???:??????)");
  60         /* Print device name. */
  61         if (block->gdp)
  62                 seq_printf(m, " is %-8s", block->gdp->disk_name);
  63         else
  64                 seq_printf(m, " is ????????");
  65         /* Print devices features. */
  66         substr = (device->features & DASD_FEATURE_READONLY) ? "(ro)" : " ";
  67         seq_printf(m, "%4s: ", substr);
  68         /* Print device status information. */
  69         switch (device->state) {
  70         case DASD_STATE_NEW:
  71                 seq_printf(m, "new");
  72                 break;
  73         case DASD_STATE_KNOWN:
  74                 seq_printf(m, "detected");
  75                 break;
  76         case DASD_STATE_BASIC:
  77                 seq_printf(m, "basic");
  78                 break;
  79         case DASD_STATE_UNFMT:
  80                 seq_printf(m, "unformatted");
  81                 break;
  82         case DASD_STATE_READY:
  83         case DASD_STATE_ONLINE:
  84                 seq_printf(m, "active ");
  85                 if (dasd_check_blocksize(block->bp_block))
  86                         seq_printf(m, "n/f       ");
  87                 else
  88                         seq_printf(m,
  89                                    "at blocksize: %u, %lu blocks, %lu MB",
  90                                    block->bp_block, block->blocks,
  91                                    ((block->bp_block >> 9) *
  92                                     block->blocks) >> 11);
  93                 break;
  94         default:
  95                 seq_printf(m, "no stat");
  96                 break;
  97         }
  98         dasd_put_device(device);
  99         if (dasd_probeonly)
 100                 seq_printf(m, "(probeonly)");
 101         seq_printf(m, "\n");
 102         return 0;
 103 }
 104
 105 static void *dasd_devices_start(struct seq_file *m, loff_t *pos)
 106 {
 107         if (*pos >= dasd_max_devindex)
 108                 return NULL;
 109         return (void *)((unsigned long) *pos + 1);
 110 }
 111
 112 static void *dasd_devices_next(struct seq_file *m, void *v, loff_t *pos)
 113 {
 114         ++*pos;
 115         return dasd_devices_start(m, pos);
 116 }
 117
 118 static void dasd_devices_stop(struct seq_file *m, void *v)
 119 {
 120 }
 121
 122 static const struct seq_operations dasd_devices_seq_ops = {
 123         .start          = dasd_devices_start,
 124         .next           = dasd_devices_next,
 125         .stop           = dasd_devices_stop,
 126         .show           = dasd_devices_show,
 127 };
 128
 129 #ifdef CONFIG_DASD_PROFILE
 130 static int dasd_stats_all_block_on(void)
 131 {
 132         int i, rc;
 133         struct dasd_device *device;
 134
 135         rc = 0;
 136         for (i = 0; i < dasd_max_devindex; ++i) {
 137                 device = dasd_device_from_devindex(i);
 138                 if (IS_ERR(device))
 139                         continue;
 140                 if (device->block)
 141                         rc = dasd_profile_on(&device->block->profile);
 142                 dasd_put_device(device);
 143                 if (rc)
 144                         return rc;
 145         }
 146         return 0;
 147 }
 148
 149 static void dasd_stats_all_block_off(void)
 150 {
 151         int i;
 152         struct dasd_device *device;
 153
 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                         dasd_profile_off(&device->block->profile);
 160                 dasd_put_device(device);
 161         }
 162 }
 163
 164 static void dasd_stats_all_block_reset(void)
 165 {
 166         int i;
 167         struct dasd_device *device;
 168
 169         for (i = 0; i < dasd_max_devindex; ++i) {
 170                 device = dasd_device_from_devindex(i);
 171                 if (IS_ERR(device))
 172                         continue;
 173                 if (device->block)
 174                         dasd_profile_reset(&device->block->profile);
 175                 dasd_put_device(device);
 176         }
 177 }
 178
 179 static void dasd_statistics_array(struct seq_file *m, unsigned int *array, int factor)
 180 {
 181         int i;
 182
 183         for (i = 0; i < 32; i++) {
 184                 seq_printf(m, "%7d ", array[i] / factor);
 185                 if (i == 15)
 186                         seq_putc(m, '\n');
 187         }
 188         seq_putc(m, '\n');
 189 }
 190 #endif /* CONFIG_DASD_PROFILE */
 191
 192 static int dasd_stats_proc_show(struct seq_file *m, void *v)
 193 {
 194 #ifdef CONFIG_DASD_PROFILE
 195         struct dasd_profile_info *prof;
 196         int factor;
 197
 198         spin_lock_bh(&dasd_global_profile.lock);
 199         prof = dasd_global_profile.data;
 200         if (!prof) {
 201                 spin_unlock_bh(&dasd_global_profile.lock);
 202                 seq_printf(m, "Statistics are off - they might be "
 203                                     "switched on using 'echo set on > "
 204                                     "/proc/dasd/statistics'\n");
 205                 return 0;
 206         }
 207
 208         /* prevent counter 'overflow' on output */
 209         for (factor = 1; (prof->dasd_io_reqs / factor) > 9999999;
 210              factor *= 10);
 211
 212         seq_printf(m, "%d dasd I/O requests\n", prof->dasd_io_reqs);
 213         seq_printf(m, "with %u sectors(512B each)\n",
 214                        prof->dasd_io_sects);
 215         seq_printf(m, "Scale Factor is  %d\n", factor);
 216         seq_printf(m,
 217                        "   __<4    ___8    __16    __32    __64    _128 "
 218                        "   _256    _512    __1k    __2k    __4k    __8k "
 219                        "   _16k    _32k    _64k    128k\n");
 220         seq_printf(m,
 221                        "   _256    _512    __1M    __2M    __4M    __8M "
 222                        "   _16M    _32M    _64M    128M    256M    512M "
 223                        "   __1G    __2G    __4G " "   _>4G\n");
 224
 225         seq_printf(m, "Histogram of sizes (512B secs)\n");
 226         dasd_statistics_array(m, prof->dasd_io_secs, factor);
 227         seq_printf(m, "Histogram of I/O times (microseconds)\n");
 228         dasd_statistics_array(m, prof->dasd_io_times, factor);
 229         seq_printf(m, "Histogram of I/O times per sector\n");
 230         dasd_statistics_array(m, prof->dasd_io_timps, factor);
 231         seq_printf(m, "Histogram of I/O time till ssch\n");
 232         dasd_statistics_array(m, prof->dasd_io_time1, factor);
 233         seq_printf(m, "Histogram of I/O time between ssch and irq\n");
 234         dasd_statistics_array(m, prof->dasd_io_time2, factor);
 235         seq_printf(m, "Histogram of I/O time between ssch "
 236                             "and irq per sector\n");
 237         dasd_statistics_array(m, prof->dasd_io_time2ps, factor);
 238         seq_printf(m, "Histogram of I/O time between irq and end\n");
 239         dasd_statistics_array(m, prof->dasd_io_time3, factor);
 240         seq_printf(m, "# of req in chanq at enqueuing (1..32) \n");
 241         dasd_statistics_array(m, prof->dasd_io_nr_req, factor);
 242         spin_unlock_bh(&dasd_global_profile.lock);
 243 #else
 244         seq_printf(m, "Statistics are not activated in this kernel\n");
 245 #endif
 246         return 0;
 247 }
 248
 249 static int dasd_stats_proc_open(struct inode *inode, struct file *file)
 250 {
 251         return single_open(file, dasd_stats_proc_show, NULL);
 252 }
 253
 254 static ssize_t dasd_stats_proc_write(struct file *file,
 255                 const char __user *user_buf, size_t user_len, loff_t *pos)
 256 {
 257 #ifdef CONFIG_DASD_PROFILE
 258         char *buffer, *str;
 259         int rc;
 260
 261         if (user_len > 65536)
 262                 user_len = 65536;
 263         buffer = dasd_get_user_string(user_buf, user_len);
 264         if (IS_ERR(buffer))
 265                 return PTR_ERR(buffer);
 266
 267         /* check for valid verbs */
 268         str = skip_spaces(buffer);
 269         if (strncmp(str, "set", 3) == 0 && isspace(str[3])) {
 270                 /* 'set xxx' was given */
 271                 str = skip_spaces(str + 4);
 272                 if (strcmp(str, "on") == 0) {
 273                         /* switch on statistics profiling */
 274                         rc = dasd_stats_all_block_on();
 275                         if (rc) {
 276                                 dasd_stats_all_block_off();
 277                                 goto out_error;
 278                         }
 279                         rc = dasd_profile_on(&dasd_global_profile);
 280                         if (rc) {
 281                                 dasd_stats_all_block_off();
 282                                 goto out_error;
 283                         }
 284                         dasd_profile_reset(&dasd_global_profile);
 285                         dasd_global_profile_level = DASD_PROFILE_ON;
 286                         pr_info("The statistics feature has been switched "
 287                                 "on\n");
 288                 } else if (strcmp(str, "off") == 0) {
 289                         /* switch off statistics profiling */
 290                         dasd_global_profile_level = DASD_PROFILE_OFF;
 291                         dasd_profile_off(&dasd_global_profile);
 292                         dasd_stats_all_block_off();
 293                         pr_info("The statistics feature has been switched "
 294                                 "off\n");
 295                 } else
 296                         goto out_parse_error;
 297         } else if (strncmp(str, "reset", 5) == 0) {
 298                 /* reset the statistics */
 299                 dasd_profile_reset(&dasd_global_profile);
 300                 dasd_stats_all_block_reset();
 301                 pr_info("The statistics have been reset\n");
 302         } else
 303                 goto out_parse_error;
 304         vfree(buffer);
 305         return user_len;
 306 out_parse_error:
 307         rc = -EINVAL;
 308         pr_warn("%s is not a supported value for /proc/dasd/statistics\n", str);
 309 out_error:
 310         vfree(buffer);
 311         return rc;
 312 #else
 313         pr_warn("/proc/dasd/statistics: is not activated in this kernel\n");
 314         return user_len;
 315 #endif                          /* CONFIG_DASD_PROFILE */
 316 }
 317
 318 static const struct proc_ops dasd_stats_proc_ops = {
 319         .proc_open      = dasd_stats_proc_open,
 320         .proc_read      = seq_read,
 321         .proc_lseek     = seq_lseek,
 322         .proc_release   = single_release,
 323         .proc_write     = dasd_stats_proc_write,
 324 };
 325
 326 /*
 327  * Create dasd proc-fs entries.
 328  * In case creation failed, cleanup and return -ENOENT.
 329  */
 330 int
 331 dasd_proc_init(void)
 332 {
 333         dasd_proc_root_entry = proc_mkdir("dasd", NULL);
 334         if (!dasd_proc_root_entry)
 335                 goto out_nodasd;
 336         dasd_devices_entry = proc_create_seq("devices", 0444,
 337                                          dasd_proc_root_entry,
 338                                          &dasd_devices_seq_ops);
 339         if (!dasd_devices_entry)
 340                 goto out_nodevices;
 341         dasd_statistics_entry = proc_create("statistics",
 342                                             S_IFREG | S_IRUGO | S_IWUSR,
 343                                             dasd_proc_root_entry,
 344                                             &dasd_stats_proc_ops);
 345         if (!dasd_statistics_entry)
 346                 goto out_nostatistics;
 347         return 0;
 348
 349  out_nostatistics:
 350         remove_proc_entry("devices", dasd_proc_root_entry);
 351  out_nodevices:
 352         remove_proc_entry("dasd", NULL);
 353  out_nodasd:
 354         return -ENOENT;
 355 }
 356
 357 void
 358 dasd_proc_exit(void)
 359 {
 360         remove_proc_entry("devices", dasd_proc_root_entry);
 361         remove_proc_entry("statistics", dasd_proc_root_entry);
 362         remove_proc_entry("dasd", NULL);
 363 }