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: %02d\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_printf(s, "%c", sdev->vendor[i]);
 193                 else
 194                         seq_printf(s, " ");
 195         }
 196
 197         seq_printf(s, " Model: ");
 198         for (i = 0; i < 16; i++) {
 199                 if (sdev->model[i] >= 0x20)
 200                         seq_printf(s, "%c", sdev->model[i]);
 201                 else
 202                         seq_printf(s, " ");
 203         }
 204
 205         seq_printf(s, " Rev: ");
 206         for (i = 0; i < 4; i++) {
 207                 if (sdev->rev[i] >= 0x20)
 208                         seq_printf(s, "%c", sdev->rev[i]);
 209                 else
 210                         seq_printf(s, " ");
 211         }
 212
 213         seq_printf(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_printf(s, " CCS\n");
 220         else
 221                 seq_printf(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, 1);
 255         scsi_host_put(shost);
 256         return error;
 257 }
 258
 259 /**
 260  * scsi_remove_single_device - Respond to user request to remove a device
 261  * @host: user-supplied decimal integer
 262  * @channel: user-supplied decimal integer
 263  * @id: user-supplied decimal integer
 264  * @lun: user-supplied decimal integer
 265  *
 266  * Description: called by writing "scsi remove-single-device" to
 267  * /proc/scsi/scsi.  Does a scsi_device_lookup() and scsi_remove_device()
 268  */
 269 static int scsi_remove_single_device(uint host, uint channel, uint id, uint lun)
 270 {
 271         struct scsi_device *sdev;
 272         struct Scsi_Host *shost;
 273         int error = -ENXIO;
 274
 275         shost = scsi_host_lookup(host);
 276         if (!shost)
 277                 return error;
 278         sdev = scsi_device_lookup(shost, channel, id, lun);
 279         if (sdev) {
 280                 scsi_remove_device(sdev);
 281                 scsi_device_put(sdev);
 282                 error = 0;
 283         }
 284
 285         scsi_host_put(shost);
 286         return error;
 287 }
 288
 289 /**
 290  * proc_scsi_write - handle writes to /proc/scsi/scsi
 291  * @file: not used
 292  * @buf: buffer to write
 293  * @length: length of buf, at most PAGE_SIZE
 294  * @ppos: not used
 295  *
 296  * Description: this provides a legacy mechanism to add or remove devices by
 297  * Host, Channel, ID, and Lun.  To use,
 298  * "echo 'scsi add-single-device 0 1 2 3' > /proc/scsi/scsi" or
 299  * "echo 'scsi remove-single-device 0 1 2 3' > /proc/scsi/scsi" with
 300  * "0 1 2 3" replaced by the Host, Channel, Id, and Lun.
 301  *
 302  * Note: this seems to be aimed at parallel SCSI. Most modern busses (USB,
 303  * SATA, Firewire, Fibre Channel, etc) dynamically assign these values to
 304  * provide a unique identifier and nothing more.
 305  */
 306
 307
 308 static ssize_t proc_scsi_write(struct file *file, const char __user *buf,
 309                                size_t length, loff_t *ppos)
 310 {
 311         int host, channel, id, lun;
 312         char *buffer, *p;
 313         int err;
 314
 315         if (!buf || length > PAGE_SIZE)
 316                 return -EINVAL;
 317
 318         buffer = (char *)__get_free_page(GFP_KERNEL);
 319         if (!buffer)
 320                 return -ENOMEM;
 321
 322         err = -EFAULT;
 323         if (copy_from_user(buffer, buf, length))
 324                 goto out;
 325
 326         err = -EINVAL;
 327         if (length < PAGE_SIZE)
 328                 buffer[length] = '\0';
 329         else if (buffer[PAGE_SIZE-1])
 330                 goto out;
 331
 332         /*
 333          * Usage: echo "scsi add-single-device 0 1 2 3" >/proc/scsi/scsi
 334          * with  "0 1 2 3" replaced by your "Host Channel Id Lun".
 335          */
 336         if (!strncmp("scsi add-single-device", buffer, 22)) {
 337                 p = buffer + 23;
 338
 339                 host = simple_strtoul(p, &p, 0);
 340                 channel = simple_strtoul(p + 1, &p, 0);
 341                 id = simple_strtoul(p + 1, &p, 0);
 342                 lun = simple_strtoul(p + 1, &p, 0);
 343
 344                 err = scsi_add_single_device(host, channel, id, lun);
 345
 346         /*
 347          * Usage: echo "scsi remove-single-device 0 1 2 3" >/proc/scsi/scsi
 348          * with  "0 1 2 3" replaced by your "Host Channel Id Lun".
 349          */
 350         } else if (!strncmp("scsi remove-single-device", buffer, 25)) {
 351                 p = buffer + 26;
 352
 353                 host = simple_strtoul(p, &p, 0);
 354                 channel = simple_strtoul(p + 1, &p, 0);
 355                 id = simple_strtoul(p + 1, &p, 0);
 356                 lun = simple_strtoul(p + 1, &p, 0);
 357
 358                 err = scsi_remove_single_device(host, channel, id, lun);
 359         }
 360
 361         /*
 362          * convert success returns so that we return the
 363          * number of bytes consumed.
 364          */
 365         if (!err)
 366                 err = length;
 367
 368  out:
 369         free_page((unsigned long)buffer);
 370         return err;
 371 }
 372
 373 static int always_match(struct device *dev, void *data)
 374 {
 375         return 1;
 376 }
 377
 378 static inline struct device *next_scsi_device(struct device *start)
 379 {
 380         struct device *next = bus_find_device(&scsi_bus_type, start, NULL,
 381                                               always_match);
 382         put_device(start);
 383         return next;
 384 }
 385
 386 static void *scsi_seq_start(struct seq_file *sfile, loff_t *pos)
 387 {
 388         struct device *dev = NULL;
 389         loff_t n = *pos;
 390
 391         while ((dev = next_scsi_device(dev))) {
 392                 if (!n--)
 393                         break;
 394                 sfile->private++;
 395         }
 396         return dev;
 397 }
 398
 399 static void *scsi_seq_next(struct seq_file *sfile, void *v, loff_t *pos)
 400 {
 401         (*pos)++;
 402         sfile->private++;
 403         return next_scsi_device(v);
 404 }
 405
 406 static void scsi_seq_stop(struct seq_file *sfile, void *v)
 407 {
 408         put_device(v);
 409 }
 410
 411 static int scsi_seq_show(struct seq_file *sfile, void *dev)
 412 {
 413         if (!sfile->private)
 414                 seq_puts(sfile, "Attached devices:\n");
 415
 416         return proc_print_scsidevice(dev, sfile);
 417 }
 418
 419 static const struct seq_operations scsi_seq_ops = {
 420         .start  = scsi_seq_start,
 421         .next   = scsi_seq_next,
 422         .stop   = scsi_seq_stop,
 423         .show   = scsi_seq_show
 424 };
 425
 426 /**
 427  * proc_scsi_open - glue function
 428  * @inode: not used
 429  * @file: passed to single_open()
 430  *
 431  * Associates proc_scsi_show with this file
 432  */
 433 static int proc_scsi_open(struct inode *inode, struct file *file)
 434 {
 435         /*
 436          * We don't really need this for the write case but it doesn't
 437          * harm either.
 438          */
 439         return seq_open(file, &scsi_seq_ops);
 440 }
 441
 442 static const struct file_operations proc_scsi_operations = {
 443         .owner          = THIS_MODULE,
 444         .open           = proc_scsi_open,
 445         .read           = seq_read,
 446         .write          = proc_scsi_write,
 447         .llseek         = seq_lseek,
 448         .release        = seq_release,
 449 };
 450
 451 /**
 452  * scsi_init_procfs - create scsi and scsi/scsi in procfs
 453  */
 454 int __init scsi_init_procfs(void)
 455 {
 456         struct proc_dir_entry *pde;
 457
 458         proc_scsi = proc_mkdir("scsi", NULL);
 459         if (!proc_scsi)
 460                 goto err1;
 461
 462         pde = proc_create("scsi/scsi", 0, NULL, &proc_scsi_operations);
 463         if (!pde)
 464                 goto err2;
 465
 466         return 0;
 467
 468 err2:
 469         remove_proc_entry("scsi", NULL);
 470 err1:
 471         return -ENOMEM;
 472 }
 473
 474 /**
 475  * scsi_exit_procfs - Remove scsi/scsi and scsi from procfs
 476  */
 477 void scsi_exit_procfs(void)
 478 {
 479         remove_proc_entry("scsi/scsi", NULL);
 480         remove_proc_entry("scsi", NULL);
 481 }