drivers/scsi/scsi_proc.c

   1 /*
   2  * linux/drivers/scsi/scsi_proc.c
   3  *
   4  * The functions in this file provide an interface between
   5  * the PROC file system and the SCSI device drivers
   6  * It is mainly used for debugging, statistics and to pass
   7  * information directly to the lowlevel driver.
   8  *
   9  * (c) 1995 Michael Neuffer neuffer@goofy.zdv.uni-mainz.de
  10  * Version: 0.99.8   last change: 95/09/13
  11  *
  12  * generic command parser provided by:
  13  * Andreas Heilwagen <crashcar@informatik.uni-koblenz.de>
  14  *
  15  * generic_proc_info() support of xxxx_info() by:
  16  * Michael A. Griffith <grif@acm.org>
  17  */
  18
  19 #include <linux/module.h>
  20 #include <linux/init.h>
  21 #include <linux/string.h>
  22 #include <linux/mm.h>
  23 #include <linux/proc_fs.h>
  24 #include <linux/errno.h>
  25 #include <linux/blkdev.h>
  26 #include <linux/seq_file.h>
  27 #include <linux/mutex.h>
  28 #include <linux/gfp.h>
  29 #include <asm/uaccess.h>
  30
  31 #include <scsi/scsi.h>
  32 #include <scsi/scsi_device.h>
  33 #include <scsi/scsi_host.h>
  34 #include <scsi/scsi_transport.h>
  35
  36 #include "scsi_priv.h"
  37 #include "scsi_logging.h"
  38
  39
  40 /* 4K page size, but our output routines, use some slack for overruns */
  41 #define PROC_BLOCK_SIZE (3*1024)
  42
  43 static struct proc_dir_entry *proc_scsi;
  44
  45 /* Protect sht->present and sht->proc_dir */
  46 static DEFINE_MUTEX(global_host_template_mutex);
  47
  48 static ssize_t proc_scsi_host_write(struct file *file, const char __user *buf,
  49                            size_t count, loff_t *ppos)
  50 {
  51         struct Scsi_Host *shost = PDE_DATA(file_inode(file));
  52         ssize_t ret = -ENOMEM;
  53         char *page;
  54
  55         if (count > PROC_BLOCK_SIZE)
  56                 return -EOVERFLOW;
  57
  58         if (!shost->hostt->write_info)
  59                 return -EINVAL;
  60
  61         page = (char *)__get_free_page(GFP_KERNEL);
  62         if (page) {
  63                 ret = -EFAULT;
  64                 if (copy_from_user(page, buf, count))
  65                         goto out;
  66                 ret = shost->hostt->write_info(shost, page, count);
  67         }
  68 out:
  69         free_page((unsigned long)page);
  70         return ret;
  71 }
  72
  73 static int proc_scsi_show(struct seq_file *m, void *v)
  74 {
  75         struct Scsi_Host *shost = m->private;
  76         return shost->hostt->show_info(m, shost);
  77 }
  78
  79 static int proc_scsi_host_open(struct inode *inode, struct file *file)
  80 {
  81         return single_open_size(file, proc_scsi_show, PDE_DATA(inode),
  82                                 4 * PAGE_SIZE);
  83 }
  84
  85 static const struct file_operations proc_scsi_fops = {
  86         .open = proc_scsi_host_open,
  87         .release = single_release,
  88         .read = seq_read,
  89         .llseek = seq_lseek,
  90         .write = proc_scsi_host_write
  91 };
  92
  93 /**
  94  * scsi_proc_hostdir_add - Create directory in /proc for a scsi host
  95  * @sht: owner of this directory
  96  *
  97  * Sets sht->proc_dir to the new directory.
  98  */
  99
 100 void scsi_proc_hostdir_add(struct scsi_host_template *sht)
 101 {
 102         if (!sht->show_info)
 103                 return;
 104
 105         mutex_lock(&global_host_template_mutex);
 106         if (!sht->present++) {
 107                 sht->proc_dir = proc_mkdir(sht->proc_name, proc_scsi);
 108                 if (!sht->proc_dir)
 109                         printk(KERN_ERR "%s: proc_mkdir failed for %s\n",
 110                                __func__, sht->proc_name);
 111         }
 112         mutex_unlock(&global_host_template_mutex);
 113 }
 114
 115 /**
 116  * scsi_proc_hostdir_rm - remove directory in /proc for a scsi host
 117  * @sht: owner of directory
 118  */
 119 void scsi_proc_hostdir_rm(struct scsi_host_template *sht)
 120 {
 121         if (!sht->show_info)
 122                 return;
 123
 124         mutex_lock(&global_host_template_mutex);
 125         if (!--sht->present && sht->proc_dir) {
 126                 remove_proc_entry(sht->proc_name, proc_scsi);
 127                 sht->proc_dir = NULL;
 128         }
 129         mutex_unlock(&global_host_template_mutex);
 130 }
 131
 132
 133 /**
 134  * scsi_proc_host_add - Add entry for this host to appropriate /proc dir
 135  * @shost: host to add
 136  */
 137 void scsi_proc_host_add(struct Scsi_Host *shost)
 138 {
 139         struct scsi_host_template *sht = shost->hostt;
 140         struct proc_dir_entry *p;
 141         char name[10];
 142
 143         if (!sht->proc_dir)
 144                 return;
 145
 146         sprintf(name,"%d", shost->host_no);
 147         p = proc_create_data(name, S_IRUGO | S_IWUSR,
 148                 sht->proc_dir, &proc_scsi_fops, shost);
 149         if (!p)
 150                 printk(KERN_ERR "%s: Failed to register host %d in"
 151                        "%s\n", __func__, shost->host_no,
 152                        sht->proc_name);
 153 }
 154
 155 /**
 156  * scsi_proc_host_rm - remove this host's entry from /proc
 157  * @shost: which host
 158  */
 159 void scsi_proc_host_rm(struct Scsi_Host *shost)
 160 {
 161         char name[10];
 162
 163         if (!shost->hostt->proc_dir)
 164                 return;
 165
 166         sprintf(name,"%d", shost->host_no);
 167         remove_proc_entry(name, shost->hostt->proc_dir);
 168 }
 169 /**
 170  * proc_print_scsidevice - return data about this host
 171  * @dev: A scsi device
 172  * @data: &struct seq_file to output to.
 173  *
 174  * Description: prints Host, Channel, Id, Lun, Vendor, Model, Rev, Type,
 175  * and revision.
 176  */
 177 static int proc_print_scsidevice(struct device *dev, void *data)
 178 {
 179         struct scsi_device *sdev;
 180         struct seq_file *s = data;
 181         int i;
 182
 183         if (!scsi_is_sdev_device(dev))
 184                 goto out;
 185
 186         sdev = to_scsi_device(dev);
 187         seq_printf(s,
 188                 "Host: scsi%d Channel: %02d Id: %02d Lun: %02llu\n  Vendor: ",
 189                 sdev->host->host_no, sdev->channel, sdev->id, sdev->lun);
 190         for (i = 0; i < 8; i++) {
 191                 if (sdev->vendor[i] >= 0x20)
 192                         seq_putc(s, sdev->vendor[i]);
 193                 else
 194                         seq_putc(s, ' ');
 195         }
 196
 197         seq_puts(s, " Model: ");
 198         for (i = 0; i < 16; i++) {
 199                 if (sdev->model[i] >= 0x20)
 200                         seq_putc(s, sdev->model[i]);
 201                 else
 202                         seq_putc(s, ' ');
 203         }
 204
 205         seq_puts(s, " Rev: ");
 206         for (i = 0; i < 4; i++) {
 207                 if (sdev->rev[i] >= 0x20)
 208                         seq_putc(s, sdev->rev[i]);
 209                 else
 210                         seq_putc(s, ' ');
 211         }
 212
 213         seq_putc(s, '\n');
 214
 215         seq_printf(s, "  Type:   %s ", scsi_device_type(sdev->type));
 216         seq_printf(s, "               ANSI  SCSI revision: %02x",
 217                         sdev->scsi_level - (sdev->scsi_level > 1));
 218         if (sdev->scsi_level == 2)
 219                 seq_puts(s, " CCS\n");
 220         else
 221                 seq_putc(s, '\n');
 222
 223 out:
 224         return 0;
 225 }
 226
 227 /**
 228  * scsi_add_single_device - Respond to user request to probe for/add device
 229  * @host: user-supplied decimal integer
 230  * @channel: user-supplied decimal integer
 231  * @id: user-supplied decimal integer
 232  * @lun: user-supplied decimal integer
 233  *
 234  * Description: called by writing "scsi add-single-device" to /proc/scsi/scsi.
 235  *
 236  * does scsi_host_lookup() and either user_scan() if that transport
 237  * type supports it, or else scsi_scan_host_selected()
 238  *
 239  * Note: this seems to be aimed exclusively at SCSI parallel busses.
 240  */
 241
 242 static int scsi_add_single_device(uint host, uint channel, uint id, uint lun)
 243 {
 244         struct Scsi_Host *shost;
 245         int error = -ENXIO;
 246
 247         shost = scsi_host_lookup(host);
 248         if (!shost)
 249                 return error;
 250
 251         if (shost->transportt->user_scan)
 252                 error = shost->transportt->user_scan(shost, channel, id, lun);
 253         else
 254                 error = scsi_scan_host_selected(shost, channel, id, lun,
 255                                                 SCSI_SCAN_MANUAL);
 256         scsi_host_put(shost);
 257         return error;
 258 }
 259
 260 /**
 261  * scsi_remove_single_device - Respond to user request to remove a device
 262  * @host: user-supplied decimal integer
 263  * @channel: user-supplied decimal integer
 264  * @id: user-supplied decimal integer
 265  * @lun: user-supplied decimal integer
 266  *
 267  * Description: called by writing "scsi remove-single-device" to
 268  * /proc/scsi/scsi.  Does a scsi_device_lookup() and scsi_remove_device()
 269  */
 270 static int scsi_remove_single_device(uint host, uint channel, uint id, uint lun)
 271 {
 272         struct scsi_device *sdev;
 273         struct Scsi_Host *shost;
 274         int error = -ENXIO;
 275
 276         shost = scsi_host_lookup(host);
 277         if (!shost)
 278                 return error;
 279         sdev = scsi_device_lookup(shost, channel, id, lun);
 280         if (sdev) {
 281                 scsi_remove_device(sdev);
 282                 scsi_device_put(sdev);
 283                 error = 0;
 284         }
 285
 286         scsi_host_put(shost);
 287         return error;
 288 }
 289
 290 /**
 291  * proc_scsi_write - handle writes to /proc/scsi/scsi
 292  * @file: not used
 293  * @buf: buffer to write
 294  * @length: length of buf, at most PAGE_SIZE
 295  * @ppos: not used
 296  *
 297  * Description: this provides a legacy mechanism to add or remove devices by
 298  * Host, Channel, ID, and Lun.  To use,
 299  * "echo 'scsi add-single-device 0 1 2 3' > /proc/scsi/scsi" or
 300  * "echo 'scsi remove-single-device 0 1 2 3' > /proc/scsi/scsi" with
 301  * "0 1 2 3" replaced by the Host, Channel, Id, and Lun.
 302  *
 303  * Note: this seems to be aimed at parallel SCSI. Most modern busses (USB,
 304  * SATA, Firewire, Fibre Channel, etc) dynamically assign these values to
 305  * provide a unique identifier and nothing more.
 306  */
 307
 308
 309 static ssize_t proc_scsi_write(struct file *file, const char __user *buf,
 310                                size_t length, loff_t *ppos)
 311 {
 312         int host, channel, id, lun;
 313         char *buffer, *p;
 314         int err;
 315
 316         if (!buf || length > PAGE_SIZE)
 317                 return -EINVAL;
 318
 319         buffer = (char *)__get_free_page(GFP_KERNEL);
 320         if (!buffer)
 321                 return -ENOMEM;
 322
 323         err = -EFAULT;
 324         if (copy_from_user(buffer, buf, length))
 325                 goto out;
 326
 327         err = -EINVAL;
 328         if (length < PAGE_SIZE)
 329                 buffer[length] = '\0';
 330         else if (buffer[PAGE_SIZE-1])
 331                 goto out;
 332
 333         /*
 334          * Usage: echo "scsi add-single-device 0 1 2 3" >/proc/scsi/scsi
 335          * with  "0 1 2 3" replaced by your "Host Channel Id Lun".
 336          */
 337         if (!strncmp("scsi add-single-device", buffer, 22)) {
 338                 p = buffer + 23;
 339
 340                 host = simple_strtoul(p, &p, 0);
 341                 channel = simple_strtoul(p + 1, &p, 0);
 342                 id = simple_strtoul(p + 1, &p, 0);
 343                 lun = simple_strtoul(p + 1, &p, 0);
 344
 345                 err = scsi_add_single_device(host, channel, id, lun);
 346
 347         /*
 348          * Usage: echo "scsi remove-single-device 0 1 2 3" >/proc/scsi/scsi
 349          * with  "0 1 2 3" replaced by your "Host Channel Id Lun".
 350          */
 351         } else if (!strncmp("scsi remove-single-device", buffer, 25)) {
 352                 p = buffer + 26;
 353
 354                 host = simple_strtoul(p, &p, 0);
 355                 channel = simple_strtoul(p + 1, &p, 0);
 356                 id = simple_strtoul(p + 1, &p, 0);
 357                 lun = simple_strtoul(p + 1, &p, 0);
 358
 359                 err = scsi_remove_single_device(host, channel, id, lun);
 360         }
 361
 362         /*
 363          * convert success returns so that we return the
 364          * number of bytes consumed.
 365          */
 366         if (!err)
 367                 err = length;
 368
 369  out:
 370         free_page((unsigned long)buffer);
 371         return err;
 372 }
 373
 374 static int always_match(struct device *dev, void *data)
 375 {
 376         return 1;
 377 }
 378
 379 static inline struct device *next_scsi_device(struct device *start)
 380 {
 381         struct device *next = bus_find_device(&scsi_bus_type, start, NULL,
 382                                               always_match);
 383         put_device(start);
 384         return next;
 385 }
 386
 387 static void *scsi_seq_start(struct seq_file *sfile, loff_t *pos)
 388 {
 389         struct device *dev = NULL;
 390         loff_t n = *pos;
 391
 392         while ((dev = next_scsi_device(dev))) {
 393                 if (!n--)
 394                         break;
 395                 sfile->private++;
 396         }
 397         return dev;
 398 }
 399
 400 static void *scsi_seq_next(struct seq_file *sfile, void *v, loff_t *pos)
 401 {
 402         (*pos)++;
 403         sfile->private++;
 404         return next_scsi_device(v);
 405 }
 406
 407 static void scsi_seq_stop(struct seq_file *sfile, void *v)
 408 {
 409         put_device(v);
 410 }
 411
 412 static int scsi_seq_show(struct seq_file *sfile, void *dev)
 413 {
 414         if (!sfile->private)
 415                 seq_puts(sfile, "Attached devices:\n");
 416
 417         return proc_print_scsidevice(dev, sfile);
 418 }
 419
 420 static const struct seq_operations scsi_seq_ops = {
 421         .start  = scsi_seq_start,
 422         .next   = scsi_seq_next,
 423         .stop   = scsi_seq_stop,
 424         .show   = scsi_seq_show
 425 };
 426
 427 /**
 428  * proc_scsi_open - glue function
 429  * @inode: not used
 430  * @file: passed to single_open()
 431  *
 432  * Associates proc_scsi_show with this file
 433  */
 434 static int proc_scsi_open(struct inode *inode, struct file *file)
 435 {
 436         /*
 437          * We don't really need this for the write case but it doesn't
 438          * harm either.
 439          */
 440         return seq_open(file, &scsi_seq_ops);
 441 }
 442
 443 static const struct file_operations proc_scsi_operations = {
 444         .owner          = THIS_MODULE,
 445         .open           = proc_scsi_open,
 446         .read           = seq_read,
 447         .write          = proc_scsi_write,
 448         .llseek         = seq_lseek,
 449         .release        = seq_release,
 450 };
 451
 452 /**
 453  * scsi_init_procfs - create scsi and scsi/scsi in procfs
 454  */
 455 int __init scsi_init_procfs(void)
 456 {
 457         struct proc_dir_entry *pde;
 458
 459         proc_scsi = proc_mkdir("scsi", NULL);
 460         if (!proc_scsi)
 461                 goto err1;
 462
 463         pde = proc_create("scsi/scsi", 0, NULL, &proc_scsi_operations);
 464         if (!pde)
 465                 goto err2;
 466
 467         return 0;
 468
 469 err2:
 470         remove_proc_entry("scsi", NULL);
 471 err1:
 472         return -ENOMEM;
 473 }
 474
 475 /**
 476  * scsi_exit_procfs - Remove scsi/scsi and scsi from procfs
 477  */
 478 void scsi_exit_procfs(void)
 479 {
 480         remove_proc_entry("scsi/scsi", NULL);
 481         remove_proc_entry("scsi", NULL);
 482 }