1 /* 2 * Changes: 3 * Arnaldo Carvalho de Melo <acme@conectiva.com.br> 08/23/2000 4 * - get rid of some verify_areas and use __copy*user and __get/put_user 5 * for the ones that remain 6 */ 7 #include <linux/module.h> 8 #include <linux/blkdev.h> 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 #include <asm/uaccess.h> 16 17 #include <scsi/scsi.h> 18 #include <scsi/scsi_device.h> 19 #include <scsi/scsi_eh.h> 20 #include <scsi/scsi_host.h> 21 #include <scsi/scsi_ioctl.h> 22 #include <scsi/scsi_request.h> 23 #include <scsi/sg.h> 24 #include <scsi/scsi_dbg.h> 25 26 #include "scsi_logging.h" 27 28 #define NORMAL_RETRIES 5 29 #define IOCTL_NORMAL_TIMEOUT (10 * HZ) 30 31 #define MAX_BUF PAGE_SIZE 32 33 /** 34 * ioctl_probe -- return host identification 35 * @host: host to identify 36 * @buffer: userspace buffer for identification 37 * 38 * Return an identifying string at @buffer, if @buffer is non-NULL, filling 39 * to the length stored at * (int *) @buffer. 40 */ 41 static int ioctl_probe(struct Scsi_Host *host, void __user *buffer) 42 { 43 unsigned int len, slen; 44 const char *string; 45 46 if (buffer) { 47 if (get_user(len, (unsigned int __user *) buffer)) 48 return -EFAULT; 49 50 if (host->hostt->info) 51 string = host->hostt->info(host); 52 else 53 string = host->hostt->name; 54 if (string) { 55 slen = strlen(string); 56 if (len > slen) 57 len = slen + 1; 58 if (copy_to_user(buffer, string, len)) 59 return -EFAULT; 60 } 61 } 62 return 1; 63 } 64 65 /* 66 67 * The SCSI_IOCTL_SEND_COMMAND ioctl sends a command out to the SCSI host. 68 * The IOCTL_NORMAL_TIMEOUT and NORMAL_RETRIES variables are used. 69 * 70 * dev is the SCSI device struct ptr, *(int *) arg is the length of the 71 * input data, if any, not including the command string & counts, 72 * *((int *)arg + 1) is the output buffer size in bytes. 73 * 74 * *(char *) ((int *) arg)[2] the actual command byte. 75 * 76 * Note that if more than MAX_BUF bytes are requested to be transferred, 77 * the ioctl will fail with error EINVAL. 78 * 79 * This size *does not* include the initial lengths that were passed. 80 * 81 * The SCSI command is read from the memory location immediately after the 82 * length words, and the input data is right after the command. The SCSI 83 * routines know the command size based on the opcode decode. 84 * 85 * The output area is then filled in starting from the command byte. 86 */ 87 88 static int ioctl_internal_command(struct scsi_device *sdev, char *cmd, 89 int timeout, int retries) 90 { 91 int result; 92 struct scsi_sense_hdr sshdr; 93 94 SCSI_LOG_IOCTL(1, printk("Trying ioctl with scsi command %d\n", *cmd)); 95 96 result = scsi_execute_req(sdev, cmd, DMA_NONE, NULL, 0, 97 &sshdr, timeout, retries); 98 99 SCSI_LOG_IOCTL(2, printk("Ioctl returned 0x%x\n", result)); 100 101 if ((driver_byte(result) & DRIVER_SENSE) && 102 (scsi_sense_valid(&sshdr))) { 103 switch (sshdr.sense_key) { 104 case ILLEGAL_REQUEST: 105 if (cmd[0] == ALLOW_MEDIUM_REMOVAL) 106 sdev->lockable = 0; 107 else 108 printk(KERN_INFO "ioctl_internal_command: " 109 "ILLEGAL REQUEST asc=0x%x ascq=0x%x\n", 110 sshdr.asc, sshdr.ascq); 111 break; 112 case NOT_READY: /* This happens if there is no disc in drive */ 113 if (sdev->removable && (cmd[0] != TEST_UNIT_READY)) { 114 printk(KERN_INFO "Device not ready. Make sure" 115 " there is a disc in the drive.\n"); 116 break; 117 } 118 case UNIT_ATTENTION: 119 if (sdev->removable) { 120 sdev->changed = 1; 121 result = 0; /* This is no longer considered an error */ 122 break; 123 } 124 default: /* Fall through for non-removable media */ 125 printk(KERN_INFO "ioctl_internal_command: <%d %d %d " 126 "%d> return code = %x\n", 127 sdev->host->host_no, 128 sdev->channel, 129 sdev->id, 130 sdev->lun, 131 result); 132 scsi_print_sense_hdr(" ", &sshdr); 133 break; 134 } 135 } 136 137 SCSI_LOG_IOCTL(2, printk("IOCTL Releasing command\n")); 138 return result; 139 } 140 141 int scsi_set_medium_removal(struct scsi_device *sdev, char state) 142 { 143 char scsi_cmd[MAX_COMMAND_SIZE]; 144 int ret; 145 146 if (!sdev->removable || !sdev->lockable) 147 return 0; 148 149 scsi_cmd[0] = ALLOW_MEDIUM_REMOVAL; 150 scsi_cmd[1] = 0; 151 scsi_cmd[2] = 0; 152 scsi_cmd[3] = 0; 153 scsi_cmd[4] = state; 154 scsi_cmd[5] = 0; 155 156 ret = ioctl_internal_command(sdev, scsi_cmd, 157 IOCTL_NORMAL_TIMEOUT, NORMAL_RETRIES); 158 if (ret == 0) 159 sdev->locked = (state == SCSI_REMOVAL_PREVENT); 160 return ret; 161 } 162 EXPORT_SYMBOL(scsi_set_medium_removal); 163 164 /* 165 * This interface is deprecated - users should use the scsi generic (sg) 166 * interface instead, as this is a more flexible approach to performing 167 * generic SCSI commands on a device. 168 * 169 * The structure that we are passed should look like: 170 * 171 * struct sdata { 172 * unsigned int inlen; [i] Length of data to be written to device 173 * unsigned int outlen; [i] Length of data to be read from device 174 * unsigned char cmd[x]; [i] SCSI command (6 <= x <= 12). 175 * [o] Data read from device starts here. 176 * [o] On error, sense buffer starts here. 177 * unsigned char wdata[y]; [i] Data written to device starts here. 178 * }; 179 * Notes: 180 * - The SCSI command length is determined by examining the 1st byte 181 * of the given command. There is no way to override this. 182 * - Data transfers are limited to PAGE_SIZE (4K on i386, 8K on alpha). 183 * - The length (x + y) must be at least OMAX_SB_LEN bytes long to 184 * accommodate the sense buffer when an error occurs. 185 * The sense buffer is truncated to OMAX_SB_LEN (16) bytes so that 186 * old code will not be surprised. 187 * - If a Unix error occurs (e.g. ENOMEM) then the user will receive 188 * a negative return and the Unix error code in 'errno'. 189 * If the SCSI command succeeds then 0 is returned. 190 * Positive numbers returned are the compacted SCSI error codes (4 191 * bytes in one int) where the lowest byte is the SCSI status. 192 * See the drivers/scsi/scsi.h file for more information on this. 193 * 194 */ 195 #define OMAX_SB_LEN 16 /* Old sense buffer length */ 196 197 int scsi_ioctl_send_command(struct scsi_device *sdev, 198 struct scsi_ioctl_command __user *sic) 199 { 200 char *buf; 201 unsigned char cmd[MAX_COMMAND_SIZE]; 202 unsigned char sense[SCSI_SENSE_BUFFERSIZE]; 203 char __user *cmd_in; 204 unsigned char opcode; 205 unsigned int inlen, outlen, cmdlen; 206 unsigned int needed, buf_needed; 207 int timeout, retries, result; 208 int data_direction, gfp_mask = GFP_KERNEL; 209 210 if (!sic) 211 return -EINVAL; 212 213 if (sdev->host->unchecked_isa_dma) 214 gfp_mask |= GFP_DMA; 215 216 /* 217 * Verify that we can read at least this much. 218 */ 219 if (!access_ok(VERIFY_READ, sic, sizeof(Scsi_Ioctl_Command))) 220 return -EFAULT; 221 222 if(__get_user(inlen, &sic->inlen)) 223 return -EFAULT; 224 225 if(__get_user(outlen, &sic->outlen)) 226 return -EFAULT; 227 228 /* 229 * We do not transfer more than MAX_BUF with this interface. 230 * If the user needs to transfer more data than this, they 231 * should use scsi_generics (sg) instead. 232 */ 233 if (inlen > MAX_BUF) 234 return -EINVAL; 235 if (outlen > MAX_BUF) 236 return -EINVAL; 237 238 cmd_in = sic->data; 239 if(get_user(opcode, cmd_in)) 240 return -EFAULT; 241 242 needed = buf_needed = (inlen > outlen ? inlen : outlen); 243 if (buf_needed) { 244 buf_needed = (buf_needed + 511) & ~511; 245 if (buf_needed > MAX_BUF) 246 buf_needed = MAX_BUF; 247 buf = kmalloc(buf_needed, gfp_mask); 248 if (!buf) 249 return -ENOMEM; 250 memset(buf, 0, buf_needed); 251 if (inlen == 0) { 252 data_direction = DMA_FROM_DEVICE; 253 } else if (outlen == 0 ) { 254 data_direction = DMA_TO_DEVICE; 255 } else { 256 /* 257 * Can this ever happen? 258 */ 259 data_direction = DMA_BIDIRECTIONAL; 260 } 261 262 } else { 263 buf = NULL; 264 data_direction = DMA_NONE; 265 } 266 267 /* 268 * Obtain the command from the user's address space. 269 */ 270 cmdlen = COMMAND_SIZE(opcode); 271 272 result = -EFAULT; 273 274 if (!access_ok(VERIFY_READ, cmd_in, cmdlen + inlen)) 275 goto error; 276 277 if(__copy_from_user(cmd, cmd_in, cmdlen)) 278 goto error; 279 280 /* 281 * Obtain the data to be sent to the device (if any). 282 */ 283 284 if(copy_from_user(buf, cmd_in + cmdlen, inlen)) 285 goto error; 286 287 switch (opcode) { 288 case SEND_DIAGNOSTIC: 289 case FORMAT_UNIT: 290 timeout = FORMAT_UNIT_TIMEOUT; 291 retries = 1; 292 break; 293 case START_STOP: 294 timeout = START_STOP_TIMEOUT; 295 retries = NORMAL_RETRIES; 296 break; 297 case MOVE_MEDIUM: 298 timeout = MOVE_MEDIUM_TIMEOUT; 299 retries = NORMAL_RETRIES; 300 break; 301 case READ_ELEMENT_STATUS: 302 timeout = READ_ELEMENT_STATUS_TIMEOUT; 303 retries = NORMAL_RETRIES; 304 break; 305 case READ_DEFECT_DATA: 306 timeout = READ_DEFECT_DATA_TIMEOUT; 307 retries = 1; 308 break; 309 default: 310 timeout = IOCTL_NORMAL_TIMEOUT; 311 retries = NORMAL_RETRIES; 312 break; 313 } 314 315 result = scsi_execute(sdev, cmd, data_direction, buf, needed, 316 sense, timeout, retries, 0); 317 318 /* 319 * If there was an error condition, pass the info back to the user. 320 */ 321 if (result) { 322 int sb_len = sizeof(*sense); 323 324 sb_len = (sb_len > OMAX_SB_LEN) ? OMAX_SB_LEN : sb_len; 325 if (copy_to_user(cmd_in, sense, sb_len)) 326 result = -EFAULT; 327 } else { 328 if (copy_to_user(cmd_in, buf, outlen)) 329 result = -EFAULT; 330 } 331 332 error: 333 kfree(buf); 334 return result; 335 } 336 EXPORT_SYMBOL(scsi_ioctl_send_command); 337 338 /* 339 * The scsi_ioctl_get_pci() function places into arg the value 340 * pci_dev::slot_name (8 characters) for the PCI device (if any). 341 * Returns: 0 on success 342 * -ENXIO if there isn't a PCI device pointer 343 * (could be because the SCSI driver hasn't been 344 * updated yet, or because it isn't a SCSI 345 * device) 346 * any copy_to_user() error on failure there 347 */ 348 static int scsi_ioctl_get_pci(struct scsi_device *sdev, void __user *arg) 349 { 350 struct device *dev = scsi_get_device(sdev->host); 351 352 if (!dev) 353 return -ENXIO; 354 return copy_to_user(arg, dev->bus_id, sizeof(dev->bus_id))? -EFAULT: 0; 355 } 356 357 358 /* 359 * the scsi_ioctl() function differs from most ioctls in that it does 360 * not take a major/minor number as the dev field. Rather, it takes 361 * a pointer to a scsi_devices[] element, a structure. 362 */ 363 int scsi_ioctl(struct scsi_device *sdev, int cmd, void __user *arg) 364 { 365 char scsi_cmd[MAX_COMMAND_SIZE]; 366 367 /* No idea how this happens.... */ 368 if (!sdev) 369 return -ENXIO; 370 371 /* 372 * If we are in the middle of error recovery, don't let anyone 373 * else try and use this device. Also, if error recovery fails, it 374 * may try and take the device offline, in which case all further 375 * access to the device is prohibited. 376 */ 377 if (!scsi_block_when_processing_errors(sdev)) 378 return -ENODEV; 379 380 /* Check for deprecated ioctls ... all the ioctls which don't 381 * follow the new unique numbering scheme are deprecated */ 382 switch (cmd) { 383 case SCSI_IOCTL_SEND_COMMAND: 384 case SCSI_IOCTL_TEST_UNIT_READY: 385 case SCSI_IOCTL_BENCHMARK_COMMAND: 386 case SCSI_IOCTL_SYNC: 387 case SCSI_IOCTL_START_UNIT: 388 case SCSI_IOCTL_STOP_UNIT: 389 printk(KERN_WARNING "program %s is using a deprecated SCSI " 390 "ioctl, please convert it to SG_IO\n", current->comm); 391 break; 392 default: 393 break; 394 } 395 396 switch (cmd) { 397 case SCSI_IOCTL_GET_IDLUN: 398 if (!access_ok(VERIFY_WRITE, arg, sizeof(struct scsi_idlun))) 399 return -EFAULT; 400 401 __put_user((sdev->id & 0xff) 402 + ((sdev->lun & 0xff) << 8) 403 + ((sdev->channel & 0xff) << 16) 404 + ((sdev->host->host_no & 0xff) << 24), 405 &((struct scsi_idlun __user *)arg)->dev_id); 406 __put_user(sdev->host->unique_id, 407 &((struct scsi_idlun __user *)arg)->host_unique_id); 408 return 0; 409 case SCSI_IOCTL_GET_BUS_NUMBER: 410 return put_user(sdev->host->host_no, (int __user *)arg); 411 case SCSI_IOCTL_PROBE_HOST: 412 return ioctl_probe(sdev->host, arg); 413 case SCSI_IOCTL_SEND_COMMAND: 414 if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO)) 415 return -EACCES; 416 return scsi_ioctl_send_command(sdev, arg); 417 case SCSI_IOCTL_DOORLOCK: 418 return scsi_set_medium_removal(sdev, SCSI_REMOVAL_PREVENT); 419 case SCSI_IOCTL_DOORUNLOCK: 420 return scsi_set_medium_removal(sdev, SCSI_REMOVAL_ALLOW); 421 case SCSI_IOCTL_TEST_UNIT_READY: 422 return scsi_test_unit_ready(sdev, IOCTL_NORMAL_TIMEOUT, 423 NORMAL_RETRIES); 424 case SCSI_IOCTL_START_UNIT: 425 scsi_cmd[0] = START_STOP; 426 scsi_cmd[1] = 0; 427 scsi_cmd[2] = scsi_cmd[3] = scsi_cmd[5] = 0; 428 scsi_cmd[4] = 1; 429 return ioctl_internal_command(sdev, scsi_cmd, 430 START_STOP_TIMEOUT, NORMAL_RETRIES); 431 case SCSI_IOCTL_STOP_UNIT: 432 scsi_cmd[0] = START_STOP; 433 scsi_cmd[1] = 0; 434 scsi_cmd[2] = scsi_cmd[3] = scsi_cmd[5] = 0; 435 scsi_cmd[4] = 0; 436 return ioctl_internal_command(sdev, scsi_cmd, 437 START_STOP_TIMEOUT, NORMAL_RETRIES); 438 case SCSI_IOCTL_GET_PCI: 439 return scsi_ioctl_get_pci(sdev, arg); 440 default: 441 if (sdev->host->hostt->ioctl) 442 return sdev->host->hostt->ioctl(sdev, cmd, arg); 443 } 444 return -EINVAL; 445 } 446 EXPORT_SYMBOL(scsi_ioctl); 447 448 /* 449 * the scsi_nonblock_ioctl() function is designed for ioctls which may 450 * be executed even if the device is in recovery. 451 */ 452 int scsi_nonblockable_ioctl(struct scsi_device *sdev, int cmd, 453 void __user *arg, struct file *filp) 454 { 455 int val, result; 456 457 /* The first set of iocts may be executed even if we're doing 458 * error processing, as long as the device was opened 459 * non-blocking */ 460 if (filp && filp->f_flags & O_NONBLOCK) { 461 if (sdev->host->shost_state == SHOST_RECOVERY) 462 return -ENODEV; 463 } else if (!scsi_block_when_processing_errors(sdev)) 464 return -ENODEV; 465 466 switch (cmd) { 467 case SG_SCSI_RESET: 468 result = get_user(val, (int __user *)arg); 469 if (result) 470 return result; 471 if (val == SG_SCSI_RESET_NOTHING) 472 return 0; 473 switch (val) { 474 case SG_SCSI_RESET_DEVICE: 475 val = SCSI_TRY_RESET_DEVICE; 476 break; 477 case SG_SCSI_RESET_BUS: 478 val = SCSI_TRY_RESET_BUS; 479 break; 480 case SG_SCSI_RESET_HOST: 481 val = SCSI_TRY_RESET_HOST; 482 break; 483 default: 484 return -EINVAL; 485 } 486 if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO)) 487 return -EACCES; 488 return (scsi_reset_provider(sdev, val) == 489 SUCCESS) ? 0 : -EIO; 490 } 491 return -ENODEV; 492 } 493 EXPORT_SYMBOL(scsi_nonblockable_ioctl); 494