i386/linux/linux-2.3.21/drivers/scsi/scsi_ioctl.c

   1 #define __NO_VERSION__
   2 #include <linux/module.h>
   3
   4 #include <asm/io.h>
   5 #include <asm/uaccess.h>
   6 #include <asm/system.h>
   7 #include <asm/page.h>
   8
   9 #include <linux/interrupt.h>
  10 #include <linux/errno.h>
  11 #include <linux/kernel.h>
  12 #include <linux/sched.h>
  13 #include <linux/mm.h>
  14 #include <linux/string.h>
  15
  16 #include <linux/blk.h>
  17 #include "scsi.h"
  18 #include "hosts.h"
  19 #include <scsi/scsi_ioctl.h>
  20
  21 #define NORMAL_RETRIES                  5
  22 #define NORMAL_TIMEOUT                  (10 * HZ)
  23 #define FORMAT_UNIT_TIMEOUT             (2 * 60 * 60 * HZ)
  24 #define START_STOP_TIMEOUT              (60 * HZ)
  25 #define MOVE_MEDIUM_TIMEOUT             (5 * 60 * HZ)
  26 #define READ_ELEMENT_STATUS_TIMEOUT     (5 * 60 * HZ)
  27
  28 #define MAX_BUF PAGE_SIZE
  29
  30 #define max(a,b) (((a) > (b)) ? (a) : (b))
  31
  32 /*
  33  * If we are told to probe a host, we will return 0 if  the host is not
  34  * present, 1 if the host is present, and will return an identifying
  35  * string at *arg, if arg is non null, filling to the length stored at
  36  * (int *) arg
  37  */
  38
  39 static int ioctl_probe(struct Scsi_Host *host, void *buffer)
  40 {
  41         int temp, result;
  42         unsigned int len, slen;
  43         const char *string;
  44
  45         if ((temp = host->hostt->present) && buffer) {
  46                 result = verify_area(VERIFY_READ, buffer, sizeof(long));
  47                 if (result)
  48                         return result;
  49
  50                 get_user(len, (unsigned int *) buffer);
  51                 if (host->hostt->info)
  52                         string = host->hostt->info(host);
  53                 else
  54                         string = host->hostt->name;
  55                 if (string) {
  56                         slen = strlen(string);
  57                         if (len > slen)
  58                                 len = slen + 1;
  59                         result = verify_area(VERIFY_WRITE, buffer, len);
  60                         if (result)
  61                                 return result;
  62
  63                         copy_to_user(buffer, string, len);
  64                 }
  65         }
  66         return temp;
  67 }
  68
  69 /*
  70
  71  * The SCSI_IOCTL_SEND_COMMAND ioctl sends a command out to the SCSI host.
  72  * The NORMAL_TIMEOUT and NORMAL_RETRIES  variables are used.
  73  *
  74  * dev is the SCSI device struct ptr, *(int *) arg is the length of the
  75  * input data, if any, not including the command string & counts,
  76  * *((int *)arg + 1) is the output buffer size in bytes.
  77  *
  78  * *(char *) ((int *) arg)[2] the actual command byte.
  79  *
  80  * Note that if more than MAX_BUF bytes are requested to be transfered,
  81  * the ioctl will fail with error EINVAL.  MAX_BUF can be increased in
  82  * the future by increasing the size that scsi_malloc will accept.
  83  *
  84  * This size *does not* include the initial lengths that were passed.
  85  *
  86  * The SCSI command is read from the memory location immediately after the
  87  * length words, and the input data is right after the command.  The SCSI
  88  * routines know the command size based on the opcode decode.
  89  *
  90  * The output area is then filled in starting from the command byte.
  91  */
  92
  93 static void scsi_ioctl_done(Scsi_Cmnd * SCpnt)
  94 {
  95         struct request *req;
  96
  97         req = &SCpnt->request;
  98         req->rq_status = RQ_SCSI_DONE;  /* Busy, but indicate request done */
  99
 100         if (req->sem != NULL) {
 101                 up(req->sem);
 102         }
 103 }
 104
 105 static int ioctl_internal_command(Scsi_Device * dev, char *cmd,
 106                                   int timeout, int retries)
 107 {
 108         unsigned long flags;
 109         int result;
 110         Scsi_Cmnd *SCpnt;
 111         Scsi_Device *SDpnt;
 112
 113         spin_lock_irqsave(&io_request_lock, flags);
 114
 115         SCSI_LOG_IOCTL(1, printk("Trying ioctl with scsi command %d\n", cmd[0]));
 116         SCpnt = scsi_allocate_device(NULL, dev, 1);
 117         {
 118                 DECLARE_MUTEX_LOCKED(sem);
 119                 SCpnt->request.sem = &sem;
 120                 scsi_do_cmd(SCpnt, cmd, NULL, 0, scsi_ioctl_done, timeout, retries);
 121                 spin_unlock_irqrestore(&io_request_lock, flags);
 122                 down(&sem);
 123                 spin_lock_irqsave(&io_request_lock, flags);
 124                 SCpnt->request.sem = NULL;
 125         }
 126
 127         SCSI_LOG_IOCTL(2, printk("Ioctl returned  0x%x\n", SCpnt->result));
 128
 129         if (driver_byte(SCpnt->result) != 0)
 130                 switch (SCpnt->sense_buffer[2] & 0xf) {
 131                 case ILLEGAL_REQUEST:
 132                         if (cmd[0] == ALLOW_MEDIUM_REMOVAL)
 133                                 dev->lockable = 0;
 134                         else
 135                                 printk("SCSI device (ioctl) reports ILLEGAL REQUEST.\n");
 136                         break;
 137                 case NOT_READY: /* This happens if there is no disc in drive */
 138                         if (dev->removable && (cmd[0] != TEST_UNIT_READY)) {
 139                                 printk(KERN_INFO "Device not ready.  Make sure there is a disc in the drive.\n");
 140                                 break;
 141                         }
 142                 case UNIT_ATTENTION:
 143                         if (dev->removable) {
 144                                 dev->changed = 1;
 145                                 SCpnt->result = 0;      /* This is no longer considered an error */
 146                                 /* gag this error, VFS will log it anyway /axboe */
 147                                 /* printk(KERN_INFO "Disc change detected.\n"); */
 148                                 break;
 149                         };
 150                 default:        /* Fall through for non-removable media */
 151                         printk("SCSI error: host %d id %d lun %d return code = %x\n",
 152                                dev->host->host_no,
 153                                dev->id,
 154                                dev->lun,
 155                                SCpnt->result);
 156                         printk("\tSense class %x, sense error %x, extended sense %x\n",
 157                                sense_class(SCpnt->sense_buffer[0]),
 158                                sense_error(SCpnt->sense_buffer[0]),
 159                                SCpnt->sense_buffer[2] & 0xf);
 160
 161                 };
 162
 163         result = SCpnt->result;
 164
 165         SCSI_LOG_IOCTL(2, printk("IOCTL Releasing command\n"));
 166         SDpnt = SCpnt->device;
 167         scsi_release_command(SCpnt);
 168         SCpnt = NULL;
 169
 170         if (!SDpnt->was_reset && SDpnt->scsi_request_fn)
 171                 (*SDpnt->scsi_request_fn) ();
 172
 173         wake_up(&SDpnt->device_wait);
 174         spin_unlock_irqrestore(&io_request_lock, flags);
 175         return result;
 176 }
 177
 178 /*
 179  * This interface is depreciated - users should use the scsi generic (sg)
 180  * interface instead, as this is a more flexible approach to performing
 181  * generic SCSI commands on a device.
 182  *
 183  * The structure that we are passed should look like:
 184  *
 185  * struct sdata {
 186  *  unsigned int inlen;      [i] Length of data to be written to device
 187  *  unsigned int outlen;     [i] Length of data to be read from device
 188  *  unsigned char cmd[x];    [i] SCSI command (6 <= x <= 12).
 189  *                           [o] Data read from device starts here.
 190  *                           [o] On error, sense buffer starts here.
 191  *  unsigned char wdata[y];  [i] Data written to device starts here.
 192  * };
 193  * Notes:
 194  *   -  The SCSI command length is determined by examining the 1st byte
 195  *      of the given command. There is no way to override this.
 196  *   -  Data transfers are limited to PAGE_SIZE (4K on i386, 8K on alpha).
 197  *   -  The length (x + y) must be at least OMAX_SB_LEN bytes long to
 198  *      accomodate the sense buffer when an error occurs.
 199  *      The sense buffer is truncated to OMAX_SB_LEN (16) bytes so that
 200  *      old code will not be surprised.
 201  *   -  If a Unix error occurs (e.g. ENOMEM) then the user will receive
 202  *      a negative return and the Unix error code in 'errno'.
 203  *      If the SCSI command succeeds then 0 is returned.
 204  *      Positive numbers returned are the compacted SCSI error codes (4
 205  *      bytes in one int) where the lowest byte is the SCSI status.
 206  *      See the drivers/scsi/scsi.h file for more information on this.
 207  *
 208  */
 209 #define OMAX_SB_LEN 16   /* Old sense buffer length */
 210
 211 int scsi_ioctl_send_command(Scsi_Device * dev, Scsi_Ioctl_Command * sic)
 212 {
 213         unsigned long flags;
 214         char *buf;
 215         unsigned char cmd[12];
 216         char *cmd_in;
 217         Scsi_Cmnd *SCpnt;
 218         Scsi_Device *SDpnt;
 219         unsigned char opcode;
 220         int inlen, outlen, cmdlen;
 221         int needed, buf_needed;
 222         int timeout, retries, result;
 223
 224         if (!sic)
 225                 return -EINVAL;
 226         /*
 227          * Verify that we can read at least this much.
 228          */
 229         result = verify_area(VERIFY_READ, sic, sizeof(Scsi_Ioctl_Command));
 230         if (result)
 231                 return result;
 232
 233         get_user(inlen, &sic->inlen);
 234         get_user(outlen, &sic->outlen);
 235
 236         /*
 237          * We do not transfer more than MAX_BUF with this interface.
 238          * If the user needs to transfer more data than this, they
 239          * should use scsi_generics (sg) instead.
 240          */
 241         if (inlen > MAX_BUF)
 242                 return -EINVAL;
 243         if (outlen > MAX_BUF)
 244                 return -EINVAL;
 245
 246         cmd_in = sic->data;
 247         get_user(opcode, cmd_in);
 248
 249         needed = buf_needed = (inlen > outlen ? inlen : outlen);
 250         if (buf_needed) {
 251                 buf_needed = (buf_needed + 511) & ~511;
 252                 if (buf_needed > MAX_BUF)
 253                         buf_needed = MAX_BUF;
 254                 spin_lock_irqsave(&io_request_lock, flags);
 255                 buf = (char *) scsi_malloc(buf_needed);
 256                 spin_unlock_irqrestore(&io_request_lock, flags);
 257                 if (!buf)
 258                         return -ENOMEM;
 259                 memset(buf, 0, buf_needed);
 260         } else
 261                 buf = NULL;
 262
 263         /*
 264          * Obtain the command from the user's address space.
 265          */
 266         cmdlen = COMMAND_SIZE(opcode);
 267
 268         result = verify_area(VERIFY_READ, cmd_in, cmdlen + inlen);
 269         if (result)
 270                 return result;
 271
 272         copy_from_user(cmd, cmd_in, cmdlen);
 273
 274         /*
 275          * Obtain the data to be sent to the device (if any).
 276          */
 277         copy_from_user(buf, cmd_in + cmdlen, inlen);
 278
 279         /*
 280          * Set the lun field to the correct value.
 281          */
 282         cmd[1] = (cmd[1] & 0x1f) | (dev->lun << 5);
 283
 284         switch (opcode) {
 285         case FORMAT_UNIT:
 286                 timeout = FORMAT_UNIT_TIMEOUT;
 287                 retries = 1;
 288                 break;
 289         case START_STOP:
 290                 timeout = START_STOP_TIMEOUT;
 291                 retries = NORMAL_RETRIES;
 292                 break;
 293         case MOVE_MEDIUM:
 294                 timeout = MOVE_MEDIUM_TIMEOUT;
 295                 retries = NORMAL_RETRIES;
 296                 break;
 297         case READ_ELEMENT_STATUS:
 298                 timeout = READ_ELEMENT_STATUS_TIMEOUT;
 299                 retries = NORMAL_RETRIES;
 300                 break;
 301         default:
 302                 timeout = NORMAL_TIMEOUT;
 303                 retries = NORMAL_RETRIES;
 304                 break;
 305         }
 306
 307 #ifndef DEBUG_NO_CMD
 308
 309         spin_lock_irqsave(&io_request_lock, flags);
 310
 311         SCpnt = scsi_allocate_device(NULL, dev, 1);
 312
 313         {
 314                 DECLARE_MUTEX_LOCKED(sem);
 315                 SCpnt->request.sem = &sem;
 316                 scsi_do_cmd(SCpnt, cmd, buf, needed, scsi_ioctl_done,
 317                             timeout, retries);
 318                 spin_unlock_irqrestore(&io_request_lock, flags);
 319                 down(&sem);
 320                 SCpnt->request.sem = NULL;
 321         }
 322
 323         /*
 324          * If there was an error condition, pass the info back to the user.
 325          */
 326         if (SCpnt->result) {
 327                 int sb_len = sizeof(SCpnt->sense_buffer);
 328
 329                 sb_len = (sb_len > OMAX_SB_LEN) ? OMAX_SB_LEN : sb_len;
 330                 result = verify_area(VERIFY_WRITE, cmd_in, sb_len);
 331                 if (result)
 332                         return result;
 333                 copy_to_user(cmd_in, SCpnt->sense_buffer, sb_len);
 334         } else {
 335                 result = verify_area(VERIFY_WRITE, cmd_in, outlen);
 336                 if (result)
 337                         return result;
 338                 copy_to_user(cmd_in, buf, outlen);
 339         }
 340         result = SCpnt->result;
 341
 342         spin_lock_irqsave(&io_request_lock, flags);
 343
 344         wake_up(&SCpnt->device->device_wait);
 345         SDpnt = SCpnt->device;
 346         scsi_release_command(SCpnt);
 347         SCpnt = NULL;
 348
 349         if (buf)
 350                 scsi_free(buf, buf_needed);
 351
 352         if (SDpnt->scsi_request_fn)
 353                 (*SDpnt->scsi_request_fn) ();
 354
 355         spin_unlock_irqrestore(&io_request_lock, flags);
 356         return result;
 357 #else
 358         {
 359                 int i;
 360                 printk("scsi_ioctl : device %d.  command = ", dev->id);
 361                 for (i = 0; i < 12; ++i)
 362                         printk("%02x ", cmd[i]);
 363                 printk("\nbuffer =");
 364                 for (i = 0; i < 20; ++i)
 365                         printk("%02x ", buf[i]);
 366                 printk("\n");
 367                 printk("inlen = %d, outlen = %d, cmdlen = %d\n",
 368                        inlen, outlen, cmdlen);
 369                 printk("buffer = %d, cmd_in = %d\n", buffer, cmd_in);
 370         }
 371         return 0;
 372 #endif
 373 }
 374
 375 /*
 376  * the scsi_ioctl() function differs from most ioctls in that it does
 377  * not take a major/minor number as the dev field.  Rather, it takes
 378  * a pointer to a scsi_devices[] element, a structure.
 379  */
 380 int scsi_ioctl(Scsi_Device * dev, int cmd, void *arg)
 381 {
 382         int result;
 383         char scsi_cmd[12];
 384
 385         /* No idea how this happens.... */
 386         if (!dev)
 387                 return -ENXIO;
 388
 389         /*
 390          * If we are in the middle of error recovery, don't let anyone
 391          * else try and use this device.  Also, if error recovery fails, it
 392          * may try and take the device offline, in which case all further
 393          * access to the device is prohibited.
 394          */
 395         if (!scsi_block_when_processing_errors(dev)) {
 396                 return -ENODEV;
 397         }
 398         switch (cmd) {
 399         case SCSI_IOCTL_GET_IDLUN:
 400                 result = verify_area(VERIFY_WRITE, arg, sizeof(Scsi_Idlun));
 401                 if (result)
 402                         return result;
 403
 404                 put_user(dev->id
 405                          + (dev->lun << 8)
 406                          + (dev->channel << 16)
 407                   + ((dev->host->hostt->proc_dir->low_ino & 0xff) << 24),
 408                          &((Scsi_Idlun *) arg)->dev_id);
 409                 put_user(dev->host->unique_id, &((Scsi_Idlun *) arg)->host_unique_id);
 410                 return 0;
 411         case SCSI_IOCTL_GET_BUS_NUMBER:
 412                 result = verify_area(VERIFY_WRITE, (void *) arg, sizeof(int));
 413                 if (result)
 414                         return result;
 415                 put_user(dev->host->host_no, (int *) arg);
 416                 return 0;
 417         case SCSI_IOCTL_TAGGED_ENABLE:
 418                 if (!capable(CAP_SYS_ADMIN))
 419                         return -EACCES;
 420                 if (!dev->tagged_supported)
 421                         return -EINVAL;
 422                 dev->tagged_queue = 1;
 423                 dev->current_tag = 1;
 424                 return 0;
 425         case SCSI_IOCTL_TAGGED_DISABLE:
 426                 if (!capable(CAP_SYS_ADMIN))
 427                         return -EACCES;
 428                 if (!dev->tagged_supported)
 429                         return -EINVAL;
 430                 dev->tagged_queue = 0;
 431                 dev->current_tag = 0;
 432                 return 0;
 433         case SCSI_IOCTL_PROBE_HOST:
 434                 return ioctl_probe(dev->host, arg);
 435         case SCSI_IOCTL_SEND_COMMAND:
 436                 if (!capable(CAP_SYS_ADMIN))
 437                         return -EACCES;
 438                 return scsi_ioctl_send_command((Scsi_Device *) dev,
 439                                              (Scsi_Ioctl_Command *) arg);
 440         case SCSI_IOCTL_DOORLOCK:
 441                 if (!dev->removable || !dev->lockable)
 442                         return 0;
 443                 scsi_cmd[0] = ALLOW_MEDIUM_REMOVAL;
 444                 scsi_cmd[1] = dev->lun << 5;
 445                 scsi_cmd[2] = scsi_cmd[3] = scsi_cmd[5] = 0;
 446                 scsi_cmd[4] = SCSI_REMOVAL_PREVENT;
 447                 return ioctl_internal_command((Scsi_Device *) dev, scsi_cmd,
 448                                          NORMAL_TIMEOUT, NORMAL_RETRIES);
 449                 break;
 450         case SCSI_IOCTL_DOORUNLOCK:
 451                 if (!dev->removable || !dev->lockable)
 452                         return 0;
 453                 scsi_cmd[0] = ALLOW_MEDIUM_REMOVAL;
 454                 scsi_cmd[1] = dev->lun << 5;
 455                 scsi_cmd[2] = scsi_cmd[3] = scsi_cmd[5] = 0;
 456                 scsi_cmd[4] = SCSI_REMOVAL_ALLOW;
 457                 return ioctl_internal_command((Scsi_Device *) dev, scsi_cmd,
 458                                          NORMAL_TIMEOUT, NORMAL_RETRIES);
 459         case SCSI_IOCTL_TEST_UNIT_READY:
 460                 scsi_cmd[0] = TEST_UNIT_READY;
 461                 scsi_cmd[1] = dev->lun << 5;
 462                 scsi_cmd[2] = scsi_cmd[3] = scsi_cmd[5] = 0;
 463                 scsi_cmd[4] = 0;
 464                 return ioctl_internal_command((Scsi_Device *) dev, scsi_cmd,
 465                                          NORMAL_TIMEOUT, NORMAL_RETRIES);
 466                 break;
 467         case SCSI_IOCTL_START_UNIT:
 468                 scsi_cmd[0] = START_STOP;
 469                 scsi_cmd[1] = dev->lun << 5;
 470                 scsi_cmd[2] = scsi_cmd[3] = scsi_cmd[5] = 0;
 471                 scsi_cmd[4] = 1;
 472                 return ioctl_internal_command((Scsi_Device *) dev, scsi_cmd,
 473                                      START_STOP_TIMEOUT, NORMAL_RETRIES);
 474                 break;
 475         case SCSI_IOCTL_STOP_UNIT:
 476                 scsi_cmd[0] = START_STOP;
 477                 scsi_cmd[1] = dev->lun << 5;
 478                 scsi_cmd[2] = scsi_cmd[3] = scsi_cmd[5] = 0;
 479                 scsi_cmd[4] = 0;
 480                 return ioctl_internal_command((Scsi_Device *) dev, scsi_cmd,
 481                                      START_STOP_TIMEOUT, NORMAL_RETRIES);
 482                 break;
 483         default:
 484                 if (dev->host->hostt->ioctl)
 485                         return dev->host->hostt->ioctl(dev, cmd, arg);
 486                 return -EINVAL;
 487         }
 488         return -EINVAL;
 489 }
 490
 491 /*
 492  * Just like scsi_ioctl, only callable from kernel space with no
 493  * fs segment fiddling.
 494  */
 495
 496 int kernel_scsi_ioctl(Scsi_Device * dev, int cmd, void *arg)
 497 {
 498         mm_segment_t oldfs;
 499         int tmp;
 500         oldfs = get_fs();
 501         set_fs(get_ds());
 502         tmp = scsi_ioctl(dev, cmd, arg);
 503         set_fs(oldfs);
 504         return tmp;
 505 }
 506
 507 /*
 508  * Overrides for Emacs so that we almost follow Linus's tabbing style.
 509  * Emacs will notice this stuff at the end of the file and automatically
 510  * adjust the settings for this buffer only.  This must remain at the end
 511  * of the file.
 512  * ---------------------------------------------------------------------------
 513  * Local variables:
 514  * c-indent-level: 4
 515  * c-brace-imaginary-offset: 0
 516  * c-brace-offset: -4
 517  * c-argdecl-indent: 4
 518  * c-label-offset: -4
 519  * c-continued-statement-offset: 4
 520  * c-continued-brace-offset: 0
 521  * indent-tabs-mode: nil
 522  * tab-width: 8
 523  * End:
 524  */