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