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1 /*
2 * scsi.h Copyright (C) 1992 Drew Eckhardt
3 * generic SCSI package header file by
4 * Drew Eckhardt
5 *
6 * <drew@colorado.edu>
7 *
8 * Modified by Eric Youngdale eric@tantalus.nrl.navy.mil to
9 * add scatter-gather, multiple outstanding request, and other
10 * enhancements.
11 */
12
13 #ifndef _SCSI_H
14 #define _SCSI_H
15
16 /*
17 $Header: /usr/src/linux/kernel/blk_drv/scsi/RCS/scsi.h,v 1.3 1993/09/24 12:20:33 drew Exp $
18
19 For documentation on the OPCODES, MESSAGES, and SENSE values,
20 please consult the SCSI standard.
21
22 */
23
24 /*
25 SCSI opcodes
26 */
27
28 #define TEST_UNIT_READY 0x00
29 #define REZERO_UNIT 0x01
30 #define REQUEST_SENSE 0x03
31 #define FORMAT_UNIT 0x04
32 #define READ_BLOCK_LIMITS 0x05
33 #define REASSIGN_BLOCKS 0x07
34 #define READ_6 0x08
35 #define WRITE_6 0x0a
36 #define SEEK_6 0x0b
37 #define READ_REVERSE 0x0f
38 #define WRITE_FILEMARKS 0x10
39 #define SPACE 0x11
40 #define INQUIRY 0x12
41 #define RECOVER_BUFFERED_DATA 0x14
42 #define MODE_SELECT 0x15
43 #define RESERVE 0x16
44 #define RELEASE 0x17
45 #define COPY 0x18
46 #define ERASE 0x19
47 #define MODE_SENSE 0x1a
48 #define START_STOP 0x1b
49 #define RECEIVE_DIAGNOSTIC 0x1c
50 #define SEND_DIAGNOSTIC 0x1d
51 #define ALLOW_MEDIUM_REMOVAL 0x1e
52
53 #define READ_CAPACITY 0x25
54 #define READ_10 0x28
55 #define WRITE_10 0x2a
56 #define SEEK_10 0x2b
57 #define WRITE_VERIFY 0x2e
58 #define VERIFY 0x2f
59 #define SEARCH_HIGH 0x30
60 #define SEARCH_EQUAL 0x31
61 #define SEARCH_LOW 0x32
62 #define SET_LIMITS 0x33
63 #define PRE_FETCH 0x34
64 #define READ_POSITION 0x34
65 #define SYNCHRONIZE_CACHE 0x35
66 #define LOCK_UNLOCK_CACHE 0x36
67 #define READ_DEFECT_DATA 0x37
68 #define COMPARE 0x39
69 #define COPY_VERIFY 0x3a
70 #define WRITE_BUFFER 0x3b
71 #define READ_BUFFER 0x3c
72 #define READ_LONG 0x3e
73 #define CHANGE_DEFINITION 0x40
74 #define LOG_SELECT 0x4c
75 #define LOG_SENSE 0x4d
76 #define MODE_SELECT_10 0x55
77 #define MODE_SENSE_10 0x5a
78
79 extern volatile int in_scan_scsis;
80 extern const unsigned char scsi_command_size[8];
81 #define COMMAND_SIZE(opcode) scsi_command_size[((opcode) >> 5) & 7]
82
83 /*
84 MESSAGE CODES
85 */
86
87 #define COMMAND_COMPLETE 0x00
88 #define EXTENDED_MESSAGE 0x01
89 #define EXTENDED_MODIFY_DATA_POINTER 0x00
90 #define EXTENDED_SDTR 0x01
91 #define EXTENDED_EXTENDED_IDENTIFY 0x02 /* SCSI-I only */
92 #define EXTENDED_WDTR 0x03
93 #define SAVE_POINTERS 0x02
94 #define RESTORE_POINTERS 0x03
95 #define DISCONNECT 0x04
96 #define INITIATOR_ERROR 0x05
97 #define ABORT 0x06
98 #define MESSAGE_REJECT 0x07
99 #define NOP 0x08
100 #define MSG_PARITY_ERROR 0x09
101 #define LINKED_CMD_COMPLETE 0x0a
102 #define LINKED_FLG_CMD_COMPLETE 0x0b
103 #define BUS_DEVICE_RESET 0x0c
104
105 #define INITIATE_RECOVERY 0x0f /* SCSI-II only */
106 #define RELEASE_RECOVERY 0x10 /* SCSI-II only */
107
108 #define SIMPLE_QUEUE_TAG 0x20
109 #define HEAD_OF_QUEUE_TAG 0x21
110 #define ORDERED_QUEUE_TAG 0x22
111
112 #define IDENTIFY_BASE 0x80
113 #define IDENTIFY(can_disconnect, lun) (IDENTIFY_BASE |\
114 ((can_disconnect) ? 0x40 : 0) |\
115 ((lun) & 0x07))
116
117
118 /*
119 Status codes
120 */
121
122 #define GOOD 0x00
123 #define CHECK_CONDITION 0x01
124 #define CONDITION_GOOD 0x02
125 #define BUSY 0x04
126 #define INTERMEDIATE_GOOD 0x08
127 #define INTERMEDIATE_C_GOOD 0x0a
128 #define RESERVATION_CONFLICT 0x0c
129
130 #define STATUS_MASK 0x1e
131
132 /*
133 the return of the status word will be in the following format :
134 The low byte is the status returned by the SCSI command,
135 with vendor specific bits masked.
136
137 The next byte is the message which followed the SCSI status.
138 This allows a stos to be used, since the Intel is a little
139 endian machine.
140
141 The final byte is a host return code, which is one of the following.
142
143 IE
144 lsb msb
145 status msg host code
146
147 Our errors returned by OUR driver, NOT SCSI message. Or'd with
148 SCSI message passed back to driver <IF any>.
149 */
150
151 /* NO error */
152 #define DID_OK 0x00
153 /* Couldn't connect before timeout period */
154 #define DID_NO_CONNECT 0x01
155 /* BUS stayed busy through time out period */
156 #define DID_BUS_BUSY 0x02
157 /* TIMED OUT for other reason */
158 #define DID_TIME_OUT 0x03
159 /* BAD target. */
160 #define DID_BAD_TARGET 0x04
161 /* Told to abort for some other reason */
162 #define DID_ABORT 0x05
163 /*
164 Parity error
165 */
166 #define DID_PARITY 0x06
167 /*
168 Internal error
169 */
170 #define DID_ERROR 0x07
171 /*
172 Reset by somebody.
173 */
174 #define DID_RESET 0x08
175 /*
176 Got an interrupt we weren't expecting.
177 */
178 #define DID_BAD_INTR 0x09
179
180 /*
181 Driver status
182 */
183 #define DRIVER_OK 0x00
184
185 /*
186 These indicate the error that occured, and what is available.
187 */
188
189 #define DRIVER_BUSY 0x01
190 #define DRIVER_SOFT 0x02
191 #define DRIVER_MEDIA 0x03
192 #define DRIVER_ERROR 0x04
193
194 #define DRIVER_INVALID 0x05
195 #define DRIVER_TIMEOUT 0x06
196 #define DRIVER_HARD 0x07
197
198 #define SUGGEST_RETRY 0x10
199 #define SUGGEST_ABORT 0x20
200 #define SUGGEST_REMAP 0x30
201 #define SUGGEST_DIE 0x40
202 #define SUGGEST_SENSE 0x80
203 #define SUGGEST_IS_OK 0xff
204
205 #define DRIVER_SENSE 0x08
206
207 #define DRIVER_MASK 0x0f
208 #define SUGGEST_MASK 0xf0
209
210 /*
211
212 SENSE KEYS
213 */
214
215 #define NO_SENSE 0x00
216 #define RECOVERED_ERROR 0x01
217 #define NOT_READY 0x02
218 #define MEDIUM_ERROR 0x03
219 #define HARDWARE_ERROR 0x04
220 #define ILLEGAL_REQUEST 0x05
221 #define UNIT_ATTENTION 0x06
222 #define DATA_PROTECT 0x07
223 #define BLANK_CHECK 0x08
224 #define COPY_ABORTED 0x0a
225 #define ABORTED_COMMAND 0x0b
226 #define VOLUME_OVERFLOW 0x0d
227 #define MISCOMPARE 0x0e
228
229
230 /*
231 DEVICE TYPES
232
233 */
234
235 #define TYPE_DISK 0x00
236 #define TYPE_TAPE 0x01
237 #define TYPE_WORM 0x04 /* Treated as ROM by our system */
238 #define TYPE_ROM 0x05
239 #define TYPE_MOD 0x07 /* Magneto-optical disk - treated as TYPE_DISK */
240 #define TYPE_NO_LUN 0x7f
241
242
243 #define MAX_COMMAND_SIZE 12
244 /*
245 SCSI command sets
246
247 */
248
249 #define SCSI_UNKNOWN 0
250 #define SCSI_1 1
251 #define SCSI_1_CCS 2
252 #define SCSI_2 3
253
254 /*
255 Every SCSI command starts with a one byte OP-code.
256 The next byte's high three bits are the LUN of the
257 device. Any multi-byte quantities are stored high byte
258 first, and may have a 5 bit MSB in the same byte
259 as the LUN.
260 */
261
262
263 /*
264 The scsi_device struct contains what we know about each given scsi
265 device.
266 */
267
268 typedef struct scsi_device {
269 struct scsi_device * next; /* Used for linked list */
270 unsigned char id, lun;
271 int attached; /* # of high level drivers attached to this */
272 int access_count; /* Count of open channels/mounts */
273 struct wait_queue * device_wait; /* Used to wait if device is busy */
274 struct Scsi_Host * host;
275 void (*scsi_request_fn)(void); /* Used to jumpstart things after an ioctl */
276 void *hostdata; /* available to low-level driver */
277 char type;
278 char scsi_level;
279 unsigned writeable:1;
280 unsigned removable:1;
281 unsigned random:1;
282 unsigned changed:1; /* Data invalid due to media change */
283 unsigned busy:1; /* Used to prevent races */
284 unsigned lockable:1; /* Able to prevent media removal */
285 unsigned borken:1; /* Tell the Seagate driver to be
286 painfully slow on this device */
287 unsigned tagged_supported:1; /* Supports SCSI-II tagged queuing */
288 unsigned tagged_queue:1; /*SCSI-II tagged queuing enabled */
289 unsigned disconnect:1; /* can disconnect */
290 unsigned soft_reset:1; /* Uses soft reset option */
291 unsigned char current_tag; /* current tag */
292 unsigned sync:1; /* Negotiate for sync transfers */
293 unsigned char sync_min_period; /* Not less than this period */
294 unsigned char sync_max_offset; /* Not greater than this offset */
295 } Scsi_Device;
296 /*
297 Use these to separate status msg and our bytes
298 */
299
300 #define status_byte(result) (((result) >> 1) & 0xf)
301 #define msg_byte(result) (((result) >> 8) & 0xff)
302 #define host_byte(result) (((result) >> 16) & 0xff)
303 #define driver_byte(result) (((result) >> 24) & 0xff)
304 #define suggestion(result) (driver_byte(result) & SUGGEST_MASK)
305
306 #define sense_class(sense) (((sense) >> 4) & 0x7)
307 #define sense_error(sense) ((sense) & 0xf)
308 #define sense_valid(sense) ((sense) & 0x80);
309
310 /*
311 These are the SCSI devices available on the system.
312 */
313
314 extern Scsi_Device * scsi_devices;
315 /*
316 Initializes all SCSI devices. This scans all scsi busses.
317 */
318
319 extern unsigned long scsi_dev_init (unsigned long, unsigned long);
320
321 struct scatterlist {
322 char * address; /* Location data is to be transferred to */
323 char * alt_address; /* Location of actual if address is a
324 dma indirect buffer. NULL otherwise */
325 unsigned int length;
326 };
327
328 #define ISA_DMA_THRESHOLD (0x00ffffff)
329 #define CONTIGUOUS_BUFFERS(X,Y) ((X->b_data+X->b_size) == Y->b_data)
330
331
332 /*
333 * These are the return codes for the abort and reset functions. The mid-level
334 * code uses these to decide what to do next. Each of the low level abort
335 * and reset functions must correctly indicate what it has done.
336 */
337
338 /* We did not do anything. Wait
339 some more for this command to complete, and if this does not work, try
340 something more serious. */
341 #define SCSI_ABORT_SNOOZE 0
342
343 /* This means that we were able to abort the command. We have already
344 called the mid-level done function, and do not expect an interrupt that will
345 lead to another call to the mid-level done function for this command */
346 #define SCSI_ABORT_SUCCESS 1
347
348 /* We called for an abort of this command, and we should get an interrupt
349 when this succeeds. Thus we should not restore the timer for this
350 command in the mid-level abort function. */
351 #define SCSI_ABORT_PENDING 2
352
353 /* Unable to abort - command is currently on the bus. Grin and bear it. */
354 #define SCSI_ABORT_BUSY 3
355
356 /* The command is not active in the low level code. Command probably
357 finished. */
358 #define SCSI_ABORT_NOT_RUNNING 4
359
360 /* Something went wrong. The low level driver will indicate the correct
361 error condition when it calls scsi_done, so the mid-level abort function
362 can simply wait until this comes through */
363 #define SCSI_ABORT_ERROR 5
364
365 /* We do not know how to reset the bus, or we do not want to. Bummer.
366 Anyway, just wait a little more for the command in question, and hope that
367 it eventually finishes. If it never finishes, the SCSI device could
368 hang, so use this with caution. */
369 #define SCSI_RESET_SNOOZE 0
370
371 /* We do not know how to reset the bus, or we do not want to. Bummer.
372 We have given up on this ever completing. The mid-level code will
373 request sense information to decide how to proceed from here. */
374 #define SCSI_RESET_PUNT 1
375
376 /* This means that we were able to reset the bus. We have restarted all of
377 the commands that should be restarted, and we should be able to continue
378 on normally from here. We do not expect any interrupts that will return
379 DID_RESET to any of the other commands in the host_queue, and the mid-level
380 code does not need to do anything special to keep the commands alive. */
381 #define SCSI_RESET_SUCCESS 2
382
383 /* We called for an reset of this bus, and we should get an interrupt
384 when this succeeds. Each command should get it's own status
385 passed up to scsi_done, but this has not happened yet. */
386 #define SCSI_RESET_PENDING 3
387
388 /* We did a reset, but do not expect an interrupt to signal DID_RESET.
389 This tells the upper level code to request the sense info, and this
390 should keep the command alive. */
391 #define SCSI_RESET_WAKEUP 4
392
393 /* Something went wrong, and we do not know how to fix it. */
394 #define SCSI_RESET_ERROR 5
395
396 void * scsi_malloc(unsigned int);
397 int scsi_free(void *, unsigned int);
398 extern unsigned int dma_free_sectors; /* How much room do we have left */
399 extern unsigned int need_isa_buffer; /* True if some devices need indirection
400 buffers */
401
402 /*
403 The Scsi_Cmnd structure is used by scsi.c internally, and for communication with
404 low level drivers that support multiple outstanding commands.
405 */
406 typedef struct scsi_pointer {
407 char * ptr; /* data pointer */
408 int this_residual; /* left in this buffer */
409 struct scatterlist *buffer; /* which buffer */
410 int buffers_residual; /* how many buffers left */
411
412 volatile int Status;
413 volatile int Message;
414 volatile int have_data_in;
415 volatile int sent_command;
416 volatile int phase;
417 } Scsi_Pointer;
418
419 typedef struct scsi_cmnd {
420 struct Scsi_Host * host;
421 Scsi_Device * device;
422 unsigned char target, lun;
423 struct scsi_cmnd *next, *prev;
424
425 /* These elements define the operation we are about to perform */
426 unsigned char cmnd[12];
427 unsigned request_bufflen; /* Actual request size */
428
429 void * request_buffer; /* Actual requested buffer */
430
431 /* These elements define the operation we ultimately want to perform */
432 unsigned char data_cmnd[12];
433 unsigned short old_use_sg; /* We save use_sg here when requesting
434 sense info */
435 unsigned short use_sg; /* Number of pieces of scatter-gather */
436 unsigned short sglist_len; /* size of malloc'd scatter-gather list */
437 unsigned short abort_reason; /* If the mid-level code requests an
438 abort, this is the reason. */
439 unsigned bufflen; /* Size of data buffer */
440 void *buffer; /* Data buffer */
441
442 unsigned underflow; /* Return error if less than this amount is
443 transfered */
444
445 unsigned transfersize; /* How much we are guaranteed to transfer with
446 each SCSI transfer (ie, between disconnect /
447 reconnects. Probably == sector size */
448
449
450
451 struct request request; /* A copy of the command we are working on*/
452
453 unsigned char sense_buffer[16]; /* Sense for this command, if needed*/
454
455
456 int retries;
457 int allowed;
458 int timeout_per_command, timeout_total, timeout;
459 /*
460 * We handle the timeout differently if it happens when a reset,
461 * abort, etc are in process.
462 */
463
464 unsigned volatile char internal_timeout;
465
466 unsigned flags;
467
468 /* These variables are for the cdrom only. Once we have variable size buffers
469 in the buffer cache, they will go away. */
470 int this_count;
471 /* End of special cdrom variables */
472
473 /* Low-level done function - can be used by low-level driver to point
474 to completion function. Not used by mid/upper level code. */
475 void (*scsi_done)(struct scsi_cmnd *);
476 void (*done)(struct scsi_cmnd *); /* Mid-level done function */
477
478 /* The following fields can be written to by the host specific code.
479 Everything else should be left alone. */
480
481 Scsi_Pointer SCp; /* Scratchpad used by some host adapters */
482
483 unsigned char * host_scribble; /* The host adapter is allowed to
484 call scsi_malloc and get some memory
485 and hang it here. The host adapter
486 is also expected to call scsi_free
487 to release this memory. (The memory
488 obtained by scsi_malloc is guaranteed
489 to be at an address < 16Mb). */
490
491 int result; /* Status code from lower level driver */
492
493 unsigned char tag; /* SCSI-II queued command tag */
494 unsigned long pid; /* Process ID, starts at 0 */
495 } Scsi_Cmnd;
496
497 /*
498 scsi_abort aborts the current command that is executing on host host.
499 The error code, if non zero is returned in the host byte, otherwise
500 DID_ABORT is returned in the hostbyte.
501 */
502
503 extern int scsi_abort (Scsi_Cmnd *, int code);
504
505 extern void scsi_do_cmd (Scsi_Cmnd *, const void *cmnd ,
506 void *buffer, unsigned bufflen, void (*done)(struct scsi_cmnd *),
507 int timeout, int retries);
508
509
510 extern Scsi_Cmnd * allocate_device(struct request **, Scsi_Device *, int);
511
512 extern Scsi_Cmnd * request_queueable(struct request *, Scsi_Device *);
513 extern int scsi_reset (Scsi_Cmnd *);
514
515 extern int max_scsi_hosts;
516
517 #if defined(MAJOR_NR) && (MAJOR_NR != SCSI_TAPE_MAJOR)
518 static Scsi_Cmnd * end_scsi_request(Scsi_Cmnd * SCpnt, int uptodate, int sectors)
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519 {
520 struct request * req;
521 struct buffer_head * bh;
522
523 req = &SCpnt->request;
524 req->errors = 0;
525 if (!uptodate) {
526 printk(DEVICE_NAME " I/O error: dev %04x, sector %lu\n",
527 req->dev,req->sector);
528 }
529
530 do {
531 if ((bh = req->bh) != NULL) {
532 req->bh = bh->b_reqnext;
533 req->nr_sectors -= bh->b_size >> 9;
534 req->sector += bh->b_size >> 9;
535 bh->b_reqnext = NULL;
536 bh->b_uptodate = uptodate;
537 unlock_buffer(bh);
538 sectors -= bh->b_size >> 9;
539 if ((bh = req->bh) != NULL) {
540 req->current_nr_sectors = bh->b_size >> 9;
541 if (req->nr_sectors < req->current_nr_sectors) {
542 req->nr_sectors = req->current_nr_sectors;
543 printk("end_scsi_request: buffer-list destroyed\n");
544 }
545 }
546 }
547 } while(sectors && bh);
548 if (req->bh){
549 req->buffer = bh->b_data;
550 return SCpnt;
551 };
552 DEVICE_OFF(req->dev);
553 if (req->sem != NULL) {
554 up(req->sem);
555 }
556 req->dev = -1;
557 wake_up(&SCpnt->device->device_wait);
558 return NULL;
559 }
560
561
562 /* This is just like INIT_REQUEST, but we need to be aware of the fact
563 that an interrupt may start another request, so we run this with interrupts
564 turned off */
565
566 #define INIT_SCSI_REQUEST \
567 if (!CURRENT) {\
568 CLEAR_INTR; \
569 sti(); \
570 return; \
571 } \
572 if (MAJOR(CURRENT->dev) != MAJOR_NR) \
573 panic(DEVICE_NAME ": request list destroyed"); \
574 if (CURRENT->bh) { \
575 if (!CURRENT->bh->b_lock) \
576 panic(DEVICE_NAME ": block not locked"); \
577 }
578 #endif
579
580 #define SCSI_SLEEP(QUEUE, CONDITION) { \
581 if (CONDITION) { \
582 struct wait_queue wait = { current, NULL}; \
583 add_wait_queue(QUEUE, &wait); \
584 sleep_repeat: \
585 current->state = TASK_UNINTERRUPTIBLE; \
586 if (CONDITION) { \
587 schedule(); \
588 goto sleep_repeat; \
589 } \
590 remove_wait_queue(QUEUE, &wait); \
591 current->state = TASK_RUNNING; \
592 }; }
593
594 #endif
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*/