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