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