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 #ifdef CONFIG_DASD_PROFILE
 135 static int dasd_stats_all_block_on(void)
 136 {
 137         int i, rc;
 138         struct dasd_device *device;
 139
 140         rc = 0;
 141         for (i = 0; i < dasd_max_devindex; ++i) {
 142                 device = dasd_device_from_devindex(i);
 143                 if (IS_ERR(device))
 144                         continue;
 145                 if (device->block)
 146                         rc = dasd_profile_on(&device->block->profile);
 147                 dasd_put_device(device);
 148                 if (rc)
 149                         return rc;
 150         }
 151         return 0;
 152 }
 153
 154 static void dasd_stats_all_block_off(void)
 155 {
 156         int i;
 157         struct dasd_device *device;
 158
 159         for (i = 0; i < dasd_max_devindex; ++i) {
 160                 device = dasd_device_from_devindex(i);
 161                 if (IS_ERR(device))
 162                         continue;
 163                 if (device->block)
 164                         dasd_profile_off(&device->block->profile);
 165                 dasd_put_device(device);
 166         }
 167 }
 168
 169 static void dasd_stats_all_block_reset(void)
 170 {
 171         int i;
 172         struct dasd_device *device;
 173
 174         for (i = 0; i < dasd_max_devindex; ++i) {
 175                 device = dasd_device_from_devindex(i);
 176                 if (IS_ERR(device))
 177                         continue;
 178                 if (device->block)
 179                         dasd_profile_reset(&device->block->profile);
 180                 dasd_put_device(device);
 181         }
 182 }
 183
 184 static void dasd_statistics_array(struct seq_file *m, unsigned int *array, int factor)
 185 {
 186         int i;
 187
 188         for (i = 0; i < 32; i++) {
 189                 seq_printf(m, "%7d ", array[i] / factor);
 190                 if (i == 15)
 191                         seq_putc(m, '\n');
 192         }
 193         seq_putc(m, '\n');
 194 }
 195 #endif /* CONFIG_DASD_PROFILE */
 196
 197 static int dasd_stats_proc_show(struct seq_file *m, void *v)
 198 {
 199 #ifdef CONFIG_DASD_PROFILE
 200         struct dasd_profile_info *prof;
 201         int factor;
 202
 203         spin_lock_bh(&dasd_global_profile.lock);
 204         prof = dasd_global_profile.data;
 205         if (!prof) {
 206                 spin_unlock_bh(&dasd_global_profile.lock);
 207                 seq_printf(m, "Statistics are off - they might be "
 208                                     "switched on using 'echo set on > "
 209                                     "/proc/dasd/statistics'\n");
 210                 return 0;
 211         }
 212
 213         /* prevent counter 'overflow' on output */
 214         for (factor = 1; (prof->dasd_io_reqs / factor) > 9999999;
 215              factor *= 10);
 216
 217         seq_printf(m, "%d dasd I/O requests\n", prof->dasd_io_reqs);
 218         seq_printf(m, "with %u sectors(512B each)\n",
 219                        prof->dasd_io_sects);
 220         seq_printf(m, "Scale Factor is  %d\n", factor);
 221         seq_printf(m,
 222                        "   __<4    ___8    __16    __32    __64    _128 "
 223                        "   _256    _512    __1k    __2k    __4k    __8k "
 224                        "   _16k    _32k    _64k    128k\n");
 225         seq_printf(m,
 226                        "   _256    _512    __1M    __2M    __4M    __8M "
 227                        "   _16M    _32M    _64M    128M    256M    512M "
 228                        "   __1G    __2G    __4G " "   _>4G\n");
 229
 230         seq_printf(m, "Histogram of sizes (512B secs)\n");
 231         dasd_statistics_array(m, prof->dasd_io_secs, factor);
 232         seq_printf(m, "Histogram of I/O times (microseconds)\n");
 233         dasd_statistics_array(m, prof->dasd_io_times, factor);
 234         seq_printf(m, "Histogram of I/O times per sector\n");
 235         dasd_statistics_array(m, prof->dasd_io_timps, factor);
 236         seq_printf(m, "Histogram of I/O time till ssch\n");
 237         dasd_statistics_array(m, prof->dasd_io_time1, factor);
 238         seq_printf(m, "Histogram of I/O time between ssch and irq\n");
 239         dasd_statistics_array(m, prof->dasd_io_time2, factor);
 240         seq_printf(m, "Histogram of I/O time between ssch "
 241                             "and irq per sector\n");
 242         dasd_statistics_array(m, prof->dasd_io_time2ps, factor);
 243         seq_printf(m, "Histogram of I/O time between irq and end\n");
 244         dasd_statistics_array(m, prof->dasd_io_time3, factor);
 245         seq_printf(m, "# of req in chanq at enqueuing (1..32) \n");
 246         dasd_statistics_array(m, prof->dasd_io_nr_req, factor);
 247         spin_unlock_bh(&dasd_global_profile.lock);
 248 #else
 249         seq_printf(m, "Statistics are not activated in this kernel\n");
 250 #endif
 251         return 0;
 252 }
 253
 254 static int dasd_stats_proc_open(struct inode *inode, struct file *file)
 255 {
 256         return single_open(file, dasd_stats_proc_show, NULL);
 257 }
 258
 259 static ssize_t dasd_stats_proc_write(struct file *file,
 260                 const char __user *user_buf, size_t user_len, loff_t *pos)
 261 {
 262 #ifdef CONFIG_DASD_PROFILE
 263         char *buffer, *str;
 264         int rc;
 265
 266         if (user_len > 65536)
 267                 user_len = 65536;
 268         buffer = dasd_get_user_string(user_buf, user_len);
 269         if (IS_ERR(buffer))
 270                 return PTR_ERR(buffer);
 271
 272         /* check for valid verbs */
 273         str = skip_spaces(buffer);
 274         if (strncmp(str, "set", 3) == 0 && isspace(str[3])) {
 275                 /* 'set xxx' was given */
 276                 str = skip_spaces(str + 4);
 277                 if (strcmp(str, "on") == 0) {
 278                         /* switch on statistics profiling */
 279                         rc = dasd_stats_all_block_on();
 280                         if (rc) {
 281                                 dasd_stats_all_block_off();
 282                                 goto out_error;
 283                         }
 284                         rc = dasd_profile_on(&dasd_global_profile);
 285                         if (rc) {
 286                                 dasd_stats_all_block_off();
 287                                 goto out_error;
 288                         }
 289                         dasd_profile_reset(&dasd_global_profile);
 290                         dasd_global_profile_level = DASD_PROFILE_ON;
 291                         pr_info("The statistics feature has been switched "
 292                                 "on\n");
 293                 } else if (strcmp(str, "off") == 0) {
 294                         /* switch off statistics profiling */
 295                         dasd_global_profile_level = DASD_PROFILE_OFF;
 296                         dasd_profile_off(&dasd_global_profile);
 297                         dasd_stats_all_block_off();
 298                         pr_info("The statistics feature has been switched "
 299                                 "off\n");
 300                 } else
 301                         goto out_parse_error;
 302         } else if (strncmp(str, "reset", 5) == 0) {
 303                 /* reset the statistics */
 304                 dasd_profile_reset(&dasd_global_profile);
 305                 dasd_stats_all_block_reset();
 306                 pr_info("The statistics have been reset\n");
 307         } else
 308                 goto out_parse_error;
 309         vfree(buffer);
 310         return user_len;
 311 out_parse_error:
 312         rc = -EINVAL;
 313         pr_warn("%s is not a supported value for /proc/dasd/statistics\n", str);
 314 out_error:
 315         vfree(buffer);
 316         return rc;
 317 #else
 318         pr_warn("/proc/dasd/statistics: is not activated in this kernel\n");
 319         return user_len;
 320 #endif                          /* CONFIG_DASD_PROFILE */
 321 }
 322
 323 static const struct file_operations dasd_stats_proc_fops = {
 324         .owner          = THIS_MODULE,
 325         .open           = dasd_stats_proc_open,
 326         .read           = seq_read,
 327         .llseek         = seq_lseek,
 328         .release        = single_release,
 329         .write          = dasd_stats_proc_write,
 330 };
 331
 332 /*
 333  * Create dasd proc-fs entries.
 334  * In case creation failed, cleanup and return -ENOENT.
 335  */
 336 int
 337 dasd_proc_init(void)
 338 {
 339         dasd_proc_root_entry = proc_mkdir("dasd", NULL);
 340         if (!dasd_proc_root_entry)
 341                 goto out_nodasd;
 342         dasd_devices_entry = proc_create_seq("devices",
 343                                          S_IFREG | S_IRUGO | S_IWUSR,
 344                                          dasd_proc_root_entry,
 345                                          &dasd_devices_seq_ops);
 346         if (!dasd_devices_entry)
 347                 goto out_nodevices;
 348         dasd_statistics_entry = proc_create("statistics",
 349                                             S_IFREG | S_IRUGO | S_IWUSR,
 350                                             dasd_proc_root_entry,
 351                                             &dasd_stats_proc_fops);
 352         if (!dasd_statistics_entry)
 353                 goto out_nostatistics;
 354         return 0;
 355
 356  out_nostatistics:
 357         remove_proc_entry("devices", dasd_proc_root_entry);
 358  out_nodevices:
 359         remove_proc_entry("dasd", NULL);
 360  out_nodasd:
 361         return -ENOENT;
 362 }
 363
 364 void
 365 dasd_proc_exit(void)
 366 {
 367         remove_proc_entry("devices", dasd_proc_root_entry);
 368         remove_proc_entry("statistics", dasd_proc_root_entry);
 369         remove_proc_entry("dasd", NULL);
 370 }