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