xref: /linux/include/scsi/scsi.h (revision 93d90ad708b8da6efc0e487b66111aa9db7f70c7)
1 /*
2  * This header file contains public constants and structures used by
3  * the scsi code for linux.
4  *
5  * For documentation on the OPCODES, MESSAGES, and SENSE values,
6  * please consult the SCSI standard.
7  */
8 #ifndef _SCSI_SCSI_H
9 #define _SCSI_SCSI_H
10 
11 #include <linux/types.h>
12 #include <linux/scatterlist.h>
13 #include <linux/kernel.h>
14 
15 struct scsi_cmnd;
16 
17 enum scsi_timeouts {
18 	SCSI_DEFAULT_EH_TIMEOUT		= 10 * HZ,
19 };
20 
21 /*
22  * The maximum number of SG segments that we will put inside a
23  * scatterlist (unless chaining is used). Should ideally fit inside a
24  * single page, to avoid a higher order allocation.  We could define this
25  * to SG_MAX_SINGLE_ALLOC to pack correctly at the highest order.  The
26  * minimum value is 32
27  */
28 #define SCSI_MAX_SG_SEGMENTS	128
29 
30 /*
31  * Like SCSI_MAX_SG_SEGMENTS, but for archs that have sg chaining. This limit
32  * is totally arbitrary, a setting of 2048 will get you at least 8mb ios.
33  */
34 #ifdef CONFIG_ARCH_HAS_SG_CHAIN
35 #define SCSI_MAX_SG_CHAIN_SEGMENTS	2048
36 #else
37 #define SCSI_MAX_SG_CHAIN_SEGMENTS	SCSI_MAX_SG_SEGMENTS
38 #endif
39 
40 /*
41  * DIX-capable adapters effectively support infinite chaining for the
42  * protection information scatterlist
43  */
44 #define SCSI_MAX_PROT_SG_SEGMENTS	0xFFFF
45 
46 /*
47  * Special value for scanning to specify scanning or rescanning of all
48  * possible channels, (target) ids, or luns on a given shost.
49  */
50 #define SCAN_WILD_CARD	~0
51 
52 /*
53  *      SCSI opcodes
54  */
55 
56 #define TEST_UNIT_READY       0x00
57 #define REZERO_UNIT           0x01
58 #define REQUEST_SENSE         0x03
59 #define FORMAT_UNIT           0x04
60 #define READ_BLOCK_LIMITS     0x05
61 #define REASSIGN_BLOCKS       0x07
62 #define INITIALIZE_ELEMENT_STATUS 0x07
63 #define READ_6                0x08
64 #define WRITE_6               0x0a
65 #define SEEK_6                0x0b
66 #define READ_REVERSE          0x0f
67 #define WRITE_FILEMARKS       0x10
68 #define SPACE                 0x11
69 #define INQUIRY               0x12
70 #define RECOVER_BUFFERED_DATA 0x14
71 #define MODE_SELECT           0x15
72 #define RESERVE               0x16
73 #define RELEASE               0x17
74 #define COPY                  0x18
75 #define ERASE                 0x19
76 #define MODE_SENSE            0x1a
77 #define START_STOP            0x1b
78 #define RECEIVE_DIAGNOSTIC    0x1c
79 #define SEND_DIAGNOSTIC       0x1d
80 #define ALLOW_MEDIUM_REMOVAL  0x1e
81 
82 #define READ_FORMAT_CAPACITIES 0x23
83 #define SET_WINDOW            0x24
84 #define READ_CAPACITY         0x25
85 #define READ_10               0x28
86 #define WRITE_10              0x2a
87 #define SEEK_10               0x2b
88 #define POSITION_TO_ELEMENT   0x2b
89 #define WRITE_VERIFY          0x2e
90 #define VERIFY                0x2f
91 #define SEARCH_HIGH           0x30
92 #define SEARCH_EQUAL          0x31
93 #define SEARCH_LOW            0x32
94 #define SET_LIMITS            0x33
95 #define PRE_FETCH             0x34
96 #define READ_POSITION         0x34
97 #define SYNCHRONIZE_CACHE     0x35
98 #define LOCK_UNLOCK_CACHE     0x36
99 #define READ_DEFECT_DATA      0x37
100 #define MEDIUM_SCAN           0x38
101 #define COMPARE               0x39
102 #define COPY_VERIFY           0x3a
103 #define WRITE_BUFFER          0x3b
104 #define READ_BUFFER           0x3c
105 #define UPDATE_BLOCK          0x3d
106 #define READ_LONG             0x3e
107 #define WRITE_LONG            0x3f
108 #define CHANGE_DEFINITION     0x40
109 #define WRITE_SAME            0x41
110 #define UNMAP		      0x42
111 #define READ_TOC              0x43
112 #define READ_HEADER           0x44
113 #define GET_EVENT_STATUS_NOTIFICATION 0x4a
114 #define LOG_SELECT            0x4c
115 #define LOG_SENSE             0x4d
116 #define XDWRITEREAD_10        0x53
117 #define MODE_SELECT_10        0x55
118 #define RESERVE_10            0x56
119 #define RELEASE_10            0x57
120 #define MODE_SENSE_10         0x5a
121 #define PERSISTENT_RESERVE_IN 0x5e
122 #define PERSISTENT_RESERVE_OUT 0x5f
123 #define VARIABLE_LENGTH_CMD   0x7f
124 #define REPORT_LUNS           0xa0
125 #define SECURITY_PROTOCOL_IN  0xa2
126 #define MAINTENANCE_IN        0xa3
127 #define MAINTENANCE_OUT       0xa4
128 #define MOVE_MEDIUM           0xa5
129 #define EXCHANGE_MEDIUM       0xa6
130 #define READ_12               0xa8
131 #define SERVICE_ACTION_OUT_12 0xa9
132 #define WRITE_12              0xaa
133 #define READ_MEDIA_SERIAL_NUMBER 0xab /* Obsolete with SPC-2 */
134 #define SERVICE_ACTION_IN_12  0xab
135 #define WRITE_VERIFY_12       0xae
136 #define VERIFY_12	      0xaf
137 #define SEARCH_HIGH_12        0xb0
138 #define SEARCH_EQUAL_12       0xb1
139 #define SEARCH_LOW_12         0xb2
140 #define SECURITY_PROTOCOL_OUT 0xb5
141 #define READ_ELEMENT_STATUS   0xb8
142 #define SEND_VOLUME_TAG       0xb6
143 #define WRITE_LONG_2          0xea
144 #define EXTENDED_COPY         0x83
145 #define RECEIVE_COPY_RESULTS  0x84
146 #define ACCESS_CONTROL_IN     0x86
147 #define ACCESS_CONTROL_OUT    0x87
148 #define READ_16               0x88
149 #define COMPARE_AND_WRITE     0x89
150 #define WRITE_16              0x8a
151 #define READ_ATTRIBUTE        0x8c
152 #define WRITE_ATTRIBUTE	      0x8d
153 #define VERIFY_16	      0x8f
154 #define SYNCHRONIZE_CACHE_16  0x91
155 #define WRITE_SAME_16	      0x93
156 #define SERVICE_ACTION_BIDIRECTIONAL 0x9d
157 #define SERVICE_ACTION_IN_16  0x9e
158 #define SERVICE_ACTION_OUT_16 0x9f
159 /* values for service action in */
160 #define	SAI_READ_CAPACITY_16  0x10
161 #define SAI_GET_LBA_STATUS    0x12
162 #define SAI_REPORT_REFERRALS  0x13
163 /* values for VARIABLE_LENGTH_CMD service action codes
164  * see spc4r17 Section D.3.5, table D.7 and D.8 */
165 #define VLC_SA_RECEIVE_CREDENTIAL 0x1800
166 /* values for maintenance in */
167 #define MI_REPORT_IDENTIFYING_INFORMATION 0x05
168 #define MI_REPORT_TARGET_PGS  0x0a
169 #define MI_REPORT_ALIASES     0x0b
170 #define MI_REPORT_SUPPORTED_OPERATION_CODES 0x0c
171 #define MI_REPORT_SUPPORTED_TASK_MANAGEMENT_FUNCTIONS 0x0d
172 #define MI_REPORT_PRIORITY    0x0e
173 #define MI_REPORT_TIMESTAMP   0x0f
174 #define MI_MANAGEMENT_PROTOCOL_IN 0x10
175 /* value for MI_REPORT_TARGET_PGS ext header */
176 #define MI_EXT_HDR_PARAM_FMT  0x20
177 /* values for maintenance out */
178 #define MO_SET_IDENTIFYING_INFORMATION 0x06
179 #define MO_SET_TARGET_PGS     0x0a
180 #define MO_CHANGE_ALIASES     0x0b
181 #define MO_SET_PRIORITY       0x0e
182 #define MO_SET_TIMESTAMP      0x0f
183 #define MO_MANAGEMENT_PROTOCOL_OUT 0x10
184 /* values for variable length command */
185 #define XDREAD_32	      0x03
186 #define XDWRITE_32	      0x04
187 #define XPWRITE_32	      0x06
188 #define XDWRITEREAD_32	      0x07
189 #define READ_32		      0x09
190 #define VERIFY_32	      0x0a
191 #define WRITE_32	      0x0b
192 #define WRITE_SAME_32	      0x0d
193 
194 /* Values for T10/04-262r7 */
195 #define	ATA_16		      0x85	/* 16-byte pass-thru */
196 #define	ATA_12		      0xa1	/* 12-byte pass-thru */
197 
198 /*
199  *	SCSI command lengths
200  */
201 
202 #define SCSI_MAX_VARLEN_CDB_SIZE 260
203 
204 /* defined in T10 SCSI Primary Commands-2 (SPC2) */
205 struct scsi_varlen_cdb_hdr {
206 	__u8 opcode;        /* opcode always == VARIABLE_LENGTH_CMD */
207 	__u8 control;
208 	__u8 misc[5];
209 	__u8 additional_cdb_length;         /* total cdb length - 8 */
210 	__be16 service_action;
211 	/* service specific data follows */
212 };
213 
214 static inline unsigned
215 scsi_varlen_cdb_length(const void *hdr)
216 {
217 	return ((struct scsi_varlen_cdb_hdr *)hdr)->additional_cdb_length + 8;
218 }
219 
220 extern const unsigned char scsi_command_size_tbl[8];
221 #define COMMAND_SIZE(opcode) scsi_command_size_tbl[((opcode) >> 5) & 7]
222 
223 static inline unsigned
224 scsi_command_size(const unsigned char *cmnd)
225 {
226 	return (cmnd[0] == VARIABLE_LENGTH_CMD) ?
227 		scsi_varlen_cdb_length(cmnd) : COMMAND_SIZE(cmnd[0]);
228 }
229 
230 #ifdef CONFIG_ACPI
231 struct acpi_bus_type;
232 
233 extern int
234 scsi_register_acpi_bus_type(struct acpi_bus_type *bus);
235 
236 extern void
237 scsi_unregister_acpi_bus_type(struct acpi_bus_type *bus);
238 #endif
239 
240 /*
241  *  SCSI Architecture Model (SAM) Status codes. Taken from SAM-3 draft
242  *  T10/1561-D Revision 4 Draft dated 7th November 2002.
243  */
244 #define SAM_STAT_GOOD            0x00
245 #define SAM_STAT_CHECK_CONDITION 0x02
246 #define SAM_STAT_CONDITION_MET   0x04
247 #define SAM_STAT_BUSY            0x08
248 #define SAM_STAT_INTERMEDIATE    0x10
249 #define SAM_STAT_INTERMEDIATE_CONDITION_MET 0x14
250 #define SAM_STAT_RESERVATION_CONFLICT 0x18
251 #define SAM_STAT_COMMAND_TERMINATED 0x22	/* obsolete in SAM-3 */
252 #define SAM_STAT_TASK_SET_FULL   0x28
253 #define SAM_STAT_ACA_ACTIVE      0x30
254 #define SAM_STAT_TASK_ABORTED    0x40
255 
256 /** scsi_status_is_good - check the status return.
257  *
258  * @status: the status passed up from the driver (including host and
259  *          driver components)
260  *
261  * This returns true for known good conditions that may be treated as
262  * command completed normally
263  */
264 static inline int scsi_status_is_good(int status)
265 {
266 	/*
267 	 * FIXME: bit0 is listed as reserved in SCSI-2, but is
268 	 * significant in SCSI-3.  For now, we follow the SCSI-2
269 	 * behaviour and ignore reserved bits.
270 	 */
271 	status &= 0xfe;
272 	return ((status == SAM_STAT_GOOD) ||
273 		(status == SAM_STAT_INTERMEDIATE) ||
274 		(status == SAM_STAT_INTERMEDIATE_CONDITION_MET) ||
275 		/* FIXME: this is obsolete in SAM-3 */
276 		(status == SAM_STAT_COMMAND_TERMINATED));
277 }
278 
279 /*
280  *  Status codes. These are deprecated as they are shifted 1 bit right
281  *  from those found in the SCSI standards. This causes confusion for
282  *  applications that are ported to several OSes. Prefer SAM Status codes
283  *  above.
284  */
285 
286 #define GOOD                 0x00
287 #define CHECK_CONDITION      0x01
288 #define CONDITION_GOOD       0x02
289 #define BUSY                 0x04
290 #define INTERMEDIATE_GOOD    0x08
291 #define INTERMEDIATE_C_GOOD  0x0a
292 #define RESERVATION_CONFLICT 0x0c
293 #define COMMAND_TERMINATED   0x11
294 #define QUEUE_FULL           0x14
295 #define ACA_ACTIVE           0x18
296 #define TASK_ABORTED         0x20
297 
298 #define STATUS_MASK          0xfe
299 
300 /*
301  *  SENSE KEYS
302  */
303 
304 #define NO_SENSE            0x00
305 #define RECOVERED_ERROR     0x01
306 #define NOT_READY           0x02
307 #define MEDIUM_ERROR        0x03
308 #define HARDWARE_ERROR      0x04
309 #define ILLEGAL_REQUEST     0x05
310 #define UNIT_ATTENTION      0x06
311 #define DATA_PROTECT        0x07
312 #define BLANK_CHECK         0x08
313 #define COPY_ABORTED        0x0a
314 #define ABORTED_COMMAND     0x0b
315 #define VOLUME_OVERFLOW     0x0d
316 #define MISCOMPARE          0x0e
317 
318 
319 /*
320  *  DEVICE TYPES
321  *  Please keep them in 0x%02x format for $MODALIAS to work
322  */
323 
324 #define TYPE_DISK           0x00
325 #define TYPE_TAPE           0x01
326 #define TYPE_PRINTER        0x02
327 #define TYPE_PROCESSOR      0x03    /* HP scanners use this */
328 #define TYPE_WORM           0x04    /* Treated as ROM by our system */
329 #define TYPE_ROM            0x05
330 #define TYPE_SCANNER        0x06
331 #define TYPE_MOD            0x07    /* Magneto-optical disk -
332 				     * - treated as TYPE_DISK */
333 #define TYPE_MEDIUM_CHANGER 0x08
334 #define TYPE_COMM           0x09    /* Communications device */
335 #define TYPE_RAID           0x0c
336 #define TYPE_ENCLOSURE      0x0d    /* Enclosure Services Device */
337 #define TYPE_RBC	    0x0e
338 #define TYPE_OSD            0x11
339 #define TYPE_ZBC            0x14
340 #define TYPE_WLUN           0x1e    /* well-known logical unit */
341 #define TYPE_NO_LUN         0x7f
342 
343 /* SCSI protocols; these are taken from SPC-3 section 7.5 */
344 enum scsi_protocol {
345 	SCSI_PROTOCOL_FCP = 0,	/* Fibre Channel */
346 	SCSI_PROTOCOL_SPI = 1,	/* parallel SCSI */
347 	SCSI_PROTOCOL_SSA = 2,	/* Serial Storage Architecture - Obsolete */
348 	SCSI_PROTOCOL_SBP = 3,	/* firewire */
349 	SCSI_PROTOCOL_SRP = 4,	/* Infiniband RDMA */
350 	SCSI_PROTOCOL_ISCSI = 5,
351 	SCSI_PROTOCOL_SAS = 6,
352 	SCSI_PROTOCOL_ADT = 7,	/* Media Changers */
353 	SCSI_PROTOCOL_ATA = 8,
354 	SCSI_PROTOCOL_UNSPEC = 0xf, /* No specific protocol */
355 };
356 
357 /* Returns a human-readable name for the device */
358 extern const char * scsi_device_type(unsigned type);
359 
360 /*
361  * standard mode-select header prepended to all mode-select commands
362  */
363 
364 struct ccs_modesel_head {
365 	__u8 _r1;			/* reserved */
366 	__u8 medium;		/* device-specific medium type */
367 	__u8 _r2;			/* reserved */
368 	__u8 block_desc_length;	/* block descriptor length */
369 	__u8 density;		/* device-specific density code */
370 	__u8 number_blocks_hi;	/* number of blocks in this block desc */
371 	__u8 number_blocks_med;
372 	__u8 number_blocks_lo;
373 	__u8 _r3;
374 	__u8 block_length_hi;	/* block length for blocks in this desc */
375 	__u8 block_length_med;
376 	__u8 block_length_lo;
377 };
378 
379 /*
380  * ScsiLun: 8 byte LUN.
381  */
382 struct scsi_lun {
383 	__u8 scsi_lun[8];
384 };
385 
386 /*
387  * The Well Known LUNS (SAM-3) in our int representation of a LUN
388  */
389 #define SCSI_W_LUN_BASE 0xc100
390 #define SCSI_W_LUN_REPORT_LUNS (SCSI_W_LUN_BASE + 1)
391 #define SCSI_W_LUN_ACCESS_CONTROL (SCSI_W_LUN_BASE + 2)
392 #define SCSI_W_LUN_TARGET_LOG_PAGE (SCSI_W_LUN_BASE + 3)
393 
394 static inline int scsi_is_wlun(u64 lun)
395 {
396 	return (lun & 0xff00) == SCSI_W_LUN_BASE;
397 }
398 
399 
400 /*
401  *  MESSAGE CODES
402  */
403 
404 #define COMMAND_COMPLETE    0x00
405 #define EXTENDED_MESSAGE    0x01
406 #define     EXTENDED_MODIFY_DATA_POINTER    0x00
407 #define     EXTENDED_SDTR                   0x01
408 #define     EXTENDED_EXTENDED_IDENTIFY      0x02    /* SCSI-I only */
409 #define     EXTENDED_WDTR                   0x03
410 #define     EXTENDED_PPR                    0x04
411 #define     EXTENDED_MODIFY_BIDI_DATA_PTR   0x05
412 #define SAVE_POINTERS       0x02
413 #define RESTORE_POINTERS    0x03
414 #define DISCONNECT          0x04
415 #define INITIATOR_ERROR     0x05
416 #define ABORT_TASK_SET      0x06
417 #define MESSAGE_REJECT      0x07
418 #define NOP                 0x08
419 #define MSG_PARITY_ERROR    0x09
420 #define LINKED_CMD_COMPLETE 0x0a
421 #define LINKED_FLG_CMD_COMPLETE 0x0b
422 #define TARGET_RESET        0x0c
423 #define ABORT_TASK          0x0d
424 #define CLEAR_TASK_SET      0x0e
425 #define INITIATE_RECOVERY   0x0f            /* SCSI-II only */
426 #define RELEASE_RECOVERY    0x10            /* SCSI-II only */
427 #define CLEAR_ACA           0x16
428 #define LOGICAL_UNIT_RESET  0x17
429 #define SIMPLE_QUEUE_TAG    0x20
430 #define HEAD_OF_QUEUE_TAG   0x21
431 #define ORDERED_QUEUE_TAG   0x22
432 #define IGNORE_WIDE_RESIDUE 0x23
433 #define ACA                 0x24
434 #define QAS_REQUEST         0x55
435 
436 /* Old SCSI2 names, don't use in new code */
437 #define BUS_DEVICE_RESET    TARGET_RESET
438 #define ABORT               ABORT_TASK_SET
439 
440 /*
441  * Host byte codes
442  */
443 
444 #define DID_OK          0x00	/* NO error                                */
445 #define DID_NO_CONNECT  0x01	/* Couldn't connect before timeout period  */
446 #define DID_BUS_BUSY    0x02	/* BUS stayed busy through time out period */
447 #define DID_TIME_OUT    0x03	/* TIMED OUT for other reason              */
448 #define DID_BAD_TARGET  0x04	/* BAD target.                             */
449 #define DID_ABORT       0x05	/* Told to abort for some other reason     */
450 #define DID_PARITY      0x06	/* Parity error                            */
451 #define DID_ERROR       0x07	/* Internal error                          */
452 #define DID_RESET       0x08	/* Reset by somebody.                      */
453 #define DID_BAD_INTR    0x09	/* Got an interrupt we weren't expecting.  */
454 #define DID_PASSTHROUGH 0x0a	/* Force command past mid-layer            */
455 #define DID_SOFT_ERROR  0x0b	/* The low level driver just wish a retry  */
456 #define DID_IMM_RETRY   0x0c	/* Retry without decrementing retry count  */
457 #define DID_REQUEUE	0x0d	/* Requeue command (no immediate retry) also
458 				 * without decrementing the retry count	   */
459 #define DID_TRANSPORT_DISRUPTED 0x0e /* Transport error disrupted execution
460 				      * and the driver blocked the port to
461 				      * recover the link. Transport class will
462 				      * retry or fail IO */
463 #define DID_TRANSPORT_FAILFAST	0x0f /* Transport class fastfailed the io */
464 #define DID_TARGET_FAILURE 0x10 /* Permanent target failure, do not retry on
465 				 * other paths */
466 #define DID_NEXUS_FAILURE 0x11  /* Permanent nexus failure, retry on other
467 				 * paths might yield different results */
468 #define DID_ALLOC_FAILURE 0x12  /* Space allocation on the device failed */
469 #define DID_MEDIUM_ERROR  0x13  /* Medium error */
470 #define DRIVER_OK       0x00	/* Driver status                           */
471 
472 /*
473  *  These indicate the error that occurred, and what is available.
474  */
475 
476 #define DRIVER_BUSY         0x01
477 #define DRIVER_SOFT         0x02
478 #define DRIVER_MEDIA        0x03
479 #define DRIVER_ERROR        0x04
480 
481 #define DRIVER_INVALID      0x05
482 #define DRIVER_TIMEOUT      0x06
483 #define DRIVER_HARD         0x07
484 #define DRIVER_SENSE	    0x08
485 
486 /*
487  * Internal return values.
488  */
489 
490 #define NEEDS_RETRY     0x2001
491 #define SUCCESS         0x2002
492 #define FAILED          0x2003
493 #define QUEUED          0x2004
494 #define SOFT_ERROR      0x2005
495 #define ADD_TO_MLQUEUE  0x2006
496 #define TIMEOUT_ERROR   0x2007
497 #define SCSI_RETURN_NOT_HANDLED   0x2008
498 #define FAST_IO_FAIL	0x2009
499 
500 /*
501  * Midlevel queue return values.
502  */
503 #define SCSI_MLQUEUE_HOST_BUSY   0x1055
504 #define SCSI_MLQUEUE_DEVICE_BUSY 0x1056
505 #define SCSI_MLQUEUE_EH_RETRY    0x1057
506 #define SCSI_MLQUEUE_TARGET_BUSY 0x1058
507 
508 /*
509  *  Use these to separate status msg and our bytes
510  *
511  *  These are set by:
512  *
513  *      status byte = set from target device
514  *      msg_byte    = return status from host adapter itself.
515  *      host_byte   = set by low-level driver to indicate status.
516  *      driver_byte = set by mid-level.
517  */
518 #define status_byte(result) (((result) >> 1) & 0x7f)
519 #define msg_byte(result)    (((result) >> 8) & 0xff)
520 #define host_byte(result)   (((result) >> 16) & 0xff)
521 #define driver_byte(result) (((result) >> 24) & 0xff)
522 
523 #define sense_class(sense)  (((sense) >> 4) & 0x7)
524 #define sense_error(sense)  ((sense) & 0xf)
525 #define sense_valid(sense)  ((sense) & 0x80)
526 
527 /*
528  * default timeouts
529 */
530 #define FORMAT_UNIT_TIMEOUT		(2 * 60 * 60 * HZ)
531 #define START_STOP_TIMEOUT		(60 * HZ)
532 #define MOVE_MEDIUM_TIMEOUT		(5 * 60 * HZ)
533 #define READ_ELEMENT_STATUS_TIMEOUT	(5 * 60 * HZ)
534 #define READ_DEFECT_DATA_TIMEOUT	(60 * HZ )
535 
536 
537 #define IDENTIFY_BASE       0x80
538 #define IDENTIFY(can_disconnect, lun)   (IDENTIFY_BASE |\
539 		     ((can_disconnect) ?  0x40 : 0) |\
540 		     ((lun) & 0x07))
541 
542 /*
543  *  struct scsi_device::scsi_level values. For SCSI devices other than those
544  *  prior to SCSI-2 (i.e. over 12 years old) this value is (resp[2] + 1)
545  *  where "resp" is a byte array of the response to an INQUIRY. The scsi_level
546  *  variable is visible to the user via sysfs.
547  */
548 
549 #define SCSI_UNKNOWN    0
550 #define SCSI_1          1
551 #define SCSI_1_CCS      2
552 #define SCSI_2          3
553 #define SCSI_3          4        /* SPC */
554 #define SCSI_SPC_2      5
555 #define SCSI_SPC_3      6
556 
557 /*
558  * INQ PERIPHERAL QUALIFIERS
559  */
560 #define SCSI_INQ_PQ_CON         0x00
561 #define SCSI_INQ_PQ_NOT_CON     0x01
562 #define SCSI_INQ_PQ_NOT_CAP     0x03
563 
564 
565 /*
566  * Here are some scsi specific ioctl commands which are sometimes useful.
567  *
568  * Note that include/linux/cdrom.h also defines IOCTL 0x5300 - 0x5395
569  */
570 
571 /* Used to obtain PUN and LUN info.  Conflicts with CDROMAUDIOBUFSIZ */
572 #define SCSI_IOCTL_GET_IDLUN		0x5382
573 
574 /* 0x5383 and 0x5384 were used for SCSI_IOCTL_TAGGED_{ENABLE,DISABLE} */
575 
576 /* Used to obtain the host number of a device. */
577 #define SCSI_IOCTL_PROBE_HOST		0x5385
578 
579 /* Used to obtain the bus number for a device */
580 #define SCSI_IOCTL_GET_BUS_NUMBER	0x5386
581 
582 /* Used to obtain the PCI location of a device */
583 #define SCSI_IOCTL_GET_PCI		0x5387
584 
585 /* Pull a u32 out of a SCSI message (using BE SCSI conventions) */
586 static inline __u32 scsi_to_u32(__u8 *ptr)
587 {
588 	return (ptr[0]<<24) + (ptr[1]<<16) + (ptr[2]<<8) + ptr[3];
589 }
590 
591 #endif /* _SCSI_SCSI_H */
592