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