xref: /openbmc/linux/drivers/ata/libata-scsi.c (revision 64c70b1c)
1 /*
2  *  libata-scsi.c - helper library for ATA
3  *
4  *  Maintained by:  Jeff Garzik <jgarzik@pobox.com>
5  *    		    Please ALWAYS copy linux-ide@vger.kernel.org
6  *		    on emails.
7  *
8  *  Copyright 2003-2004 Red Hat, Inc.  All rights reserved.
9  *  Copyright 2003-2004 Jeff Garzik
10  *
11  *
12  *  This program is free software; you can redistribute it and/or modify
13  *  it under the terms of the GNU General Public License as published by
14  *  the Free Software Foundation; either version 2, or (at your option)
15  *  any later version.
16  *
17  *  This program is distributed in the hope that it will be useful,
18  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
19  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
20  *  GNU General Public License for more details.
21  *
22  *  You should have received a copy of the GNU General Public License
23  *  along with this program; see the file COPYING.  If not, write to
24  *  the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
25  *
26  *
27  *  libata documentation is available via 'make {ps|pdf}docs',
28  *  as Documentation/DocBook/libata.*
29  *
30  *  Hardware documentation available from
31  *  - http://www.t10.org/
32  *  - http://www.t13.org/
33  *
34  */
35 
36 #include <linux/kernel.h>
37 #include <linux/blkdev.h>
38 #include <linux/spinlock.h>
39 #include <scsi/scsi.h>
40 #include <scsi/scsi_host.h>
41 #include <scsi/scsi_cmnd.h>
42 #include <scsi/scsi_eh.h>
43 #include <scsi/scsi_device.h>
44 #include <scsi/scsi_tcq.h>
45 #include <scsi/scsi_transport.h>
46 #include <linux/libata.h>
47 #include <linux/hdreg.h>
48 #include <asm/uaccess.h>
49 
50 #include "libata.h"
51 
52 #define SECTOR_SIZE	512
53 
54 typedef unsigned int (*ata_xlat_func_t)(struct ata_queued_cmd *qc);
55 
56 static struct ata_device * __ata_scsi_find_dev(struct ata_port *ap,
57 					const struct scsi_device *scsidev);
58 static struct ata_device * ata_scsi_find_dev(struct ata_port *ap,
59 					    const struct scsi_device *scsidev);
60 static int ata_scsi_user_scan(struct Scsi_Host *shost, unsigned int channel,
61 			      unsigned int id, unsigned int lun);
62 
63 
64 #define RW_RECOVERY_MPAGE 0x1
65 #define RW_RECOVERY_MPAGE_LEN 12
66 #define CACHE_MPAGE 0x8
67 #define CACHE_MPAGE_LEN 20
68 #define CONTROL_MPAGE 0xa
69 #define CONTROL_MPAGE_LEN 12
70 #define ALL_MPAGES 0x3f
71 #define ALL_SUB_MPAGES 0xff
72 
73 
74 static const u8 def_rw_recovery_mpage[] = {
75 	RW_RECOVERY_MPAGE,
76 	RW_RECOVERY_MPAGE_LEN - 2,
77 	(1 << 7) |	/* AWRE, sat-r06 say it shall be 0 */
78 	    (1 << 6),	/* ARRE (auto read reallocation) */
79 	0,		/* read retry count */
80 	0, 0, 0, 0,
81 	0,		/* write retry count */
82 	0, 0, 0
83 };
84 
85 static const u8 def_cache_mpage[CACHE_MPAGE_LEN] = {
86 	CACHE_MPAGE,
87 	CACHE_MPAGE_LEN - 2,
88 	0,		/* contains WCE, needs to be 0 for logic */
89 	0, 0, 0, 0, 0, 0, 0, 0, 0,
90 	0,		/* contains DRA, needs to be 0 for logic */
91 	0, 0, 0, 0, 0, 0, 0
92 };
93 
94 static const u8 def_control_mpage[CONTROL_MPAGE_LEN] = {
95 	CONTROL_MPAGE,
96 	CONTROL_MPAGE_LEN - 2,
97 	2,	/* DSENSE=0, GLTSD=1 */
98 	0,	/* [QAM+QERR may be 1, see 05-359r1] */
99 	0, 0, 0, 0, 0xff, 0xff,
100 	0, 30	/* extended self test time, see 05-359r1 */
101 };
102 
103 /*
104  * libata transport template.  libata doesn't do real transport stuff.
105  * It just needs the eh_timed_out hook.
106  */
107 static struct scsi_transport_template ata_scsi_transport_template = {
108 	.eh_strategy_handler	= ata_scsi_error,
109 	.eh_timed_out		= ata_scsi_timed_out,
110 	.user_scan		= ata_scsi_user_scan,
111 };
112 
113 
114 static void ata_scsi_invalid_field(struct scsi_cmnd *cmd,
115 				   void (*done)(struct scsi_cmnd *))
116 {
117 	ata_scsi_set_sense(cmd, ILLEGAL_REQUEST, 0x24, 0x0);
118 	/* "Invalid field in cbd" */
119 	done(cmd);
120 }
121 
122 /**
123  *	ata_std_bios_param - generic bios head/sector/cylinder calculator used by sd.
124  *	@sdev: SCSI device for which BIOS geometry is to be determined
125  *	@bdev: block device associated with @sdev
126  *	@capacity: capacity of SCSI device
127  *	@geom: location to which geometry will be output
128  *
129  *	Generic bios head/sector/cylinder calculator
130  *	used by sd. Most BIOSes nowadays expect a XXX/255/16  (CHS)
131  *	mapping. Some situations may arise where the disk is not
132  *	bootable if this is not used.
133  *
134  *	LOCKING:
135  *	Defined by the SCSI layer.  We don't really care.
136  *
137  *	RETURNS:
138  *	Zero.
139  */
140 int ata_std_bios_param(struct scsi_device *sdev, struct block_device *bdev,
141 		       sector_t capacity, int geom[])
142 {
143 	geom[0] = 255;
144 	geom[1] = 63;
145 	sector_div(capacity, 255*63);
146 	geom[2] = capacity;
147 
148 	return 0;
149 }
150 
151 /**
152  *	ata_get_identity - Handler for HDIO_GET_IDENTITY ioctl
153  *	@sdev: SCSI device to get identify data for
154  *	@arg: User buffer area for identify data
155  *
156  *	LOCKING:
157  *	Defined by the SCSI layer.  We don't really care.
158  *
159  *	RETURNS:
160  *	Zero on success, negative errno on error.
161  */
162 static int ata_get_identity(struct scsi_device *sdev, void __user *arg)
163 {
164 	struct ata_port *ap = ata_shost_to_port(sdev->host);
165 	struct ata_device *dev = ata_scsi_find_dev(ap, sdev);
166 	u16 __user *dst = arg;
167 	char buf[40];
168 
169 	if (!dev)
170 		return -ENOMSG;
171 
172 	if (copy_to_user(dst, dev->id, ATA_ID_WORDS * sizeof(u16)))
173 		return -EFAULT;
174 
175 	ata_id_string(dev->id, buf, ATA_ID_PROD, ATA_ID_PROD_LEN);
176 	if (copy_to_user(dst + ATA_ID_PROD, buf, ATA_ID_PROD_LEN))
177 		return -EFAULT;
178 
179 	ata_id_string(dev->id, buf, ATA_ID_FW_REV, ATA_ID_FW_REV_LEN);
180 	if (copy_to_user(dst + ATA_ID_FW_REV, buf, ATA_ID_FW_REV_LEN))
181 		return -EFAULT;
182 
183 	ata_id_string(dev->id, buf, ATA_ID_SERNO, ATA_ID_SERNO_LEN);
184 	if (copy_to_user(dst + ATA_ID_SERNO, buf, ATA_ID_SERNO_LEN))
185 		return -EFAULT;
186 
187 	return 0;
188 }
189 
190 /**
191  *	ata_cmd_ioctl - Handler for HDIO_DRIVE_CMD ioctl
192  *	@scsidev: Device to which we are issuing command
193  *	@arg: User provided data for issuing command
194  *
195  *	LOCKING:
196  *	Defined by the SCSI layer.  We don't really care.
197  *
198  *	RETURNS:
199  *	Zero on success, negative errno on error.
200  */
201 int ata_cmd_ioctl(struct scsi_device *scsidev, void __user *arg)
202 {
203 	int rc = 0;
204 	u8 scsi_cmd[MAX_COMMAND_SIZE];
205 	u8 args[4], *argbuf = NULL, *sensebuf = NULL;
206 	int argsize = 0;
207 	enum dma_data_direction data_dir;
208 	int cmd_result;
209 
210 	if (arg == NULL)
211 		return -EINVAL;
212 
213 	if (copy_from_user(args, arg, sizeof(args)))
214 		return -EFAULT;
215 
216 	sensebuf = kzalloc(SCSI_SENSE_BUFFERSIZE, GFP_NOIO);
217 	if (!sensebuf)
218 		return -ENOMEM;
219 
220 	memset(scsi_cmd, 0, sizeof(scsi_cmd));
221 
222 	if (args[3]) {
223 		argsize = SECTOR_SIZE * args[3];
224 		argbuf = kmalloc(argsize, GFP_KERNEL);
225 		if (argbuf == NULL) {
226 			rc = -ENOMEM;
227 			goto error;
228 		}
229 
230 		scsi_cmd[1]  = (4 << 1); /* PIO Data-in */
231 		scsi_cmd[2]  = 0x0e;     /* no off.line or cc, read from dev,
232 		                            block count in sector count field */
233 		data_dir = DMA_FROM_DEVICE;
234 	} else {
235 		scsi_cmd[1]  = (3 << 1); /* Non-data */
236 		scsi_cmd[2]  = 0x20;     /* cc but no off.line or data xfer */
237 		data_dir = DMA_NONE;
238 	}
239 
240 	scsi_cmd[0] = ATA_16;
241 
242 	scsi_cmd[4] = args[2];
243 	if (args[0] == WIN_SMART) { /* hack -- ide driver does this too... */
244 		scsi_cmd[6]  = args[3];
245 		scsi_cmd[8]  = args[1];
246 		scsi_cmd[10] = 0x4f;
247 		scsi_cmd[12] = 0xc2;
248 	} else {
249 		scsi_cmd[6]  = args[1];
250 	}
251 	scsi_cmd[14] = args[0];
252 
253 	/* Good values for timeout and retries?  Values below
254 	   from scsi_ioctl_send_command() for default case... */
255 	cmd_result = scsi_execute(scsidev, scsi_cmd, data_dir, argbuf, argsize,
256 	                          sensebuf, (10*HZ), 5, 0);
257 
258 	if (driver_byte(cmd_result) == DRIVER_SENSE) {/* sense data available */
259 		u8 *desc = sensebuf + 8;
260 		cmd_result &= ~(0xFF<<24); /* DRIVER_SENSE is not an error */
261 
262 		/* If we set cc then ATA pass-through will cause a
263 		 * check condition even if no error. Filter that. */
264 		if (cmd_result & SAM_STAT_CHECK_CONDITION) {
265 			struct scsi_sense_hdr sshdr;
266 			scsi_normalize_sense(sensebuf, SCSI_SENSE_BUFFERSIZE,
267 			                      &sshdr);
268 			if (sshdr.sense_key==0 &&
269 			    sshdr.asc==0 && sshdr.ascq==0)
270 				cmd_result &= ~SAM_STAT_CHECK_CONDITION;
271 		}
272 
273 		/* Send userspace a few ATA registers (same as drivers/ide) */
274 		if (sensebuf[0] == 0x72 &&     /* format is "descriptor" */
275 		    desc[0] == 0x09 ) {        /* code is "ATA Descriptor" */
276 			args[0] = desc[13];    /* status */
277 			args[1] = desc[3];     /* error */
278 			args[2] = desc[5];     /* sector count (0:7) */
279 			if (copy_to_user(arg, args, sizeof(args)))
280 				rc = -EFAULT;
281 		}
282 	}
283 
284 
285 	if (cmd_result) {
286 		rc = -EIO;
287 		goto error;
288 	}
289 
290 	if ((argbuf)
291 	 && copy_to_user(arg + sizeof(args), argbuf, argsize))
292 		rc = -EFAULT;
293 error:
294 	kfree(sensebuf);
295 	kfree(argbuf);
296 	return rc;
297 }
298 
299 /**
300  *	ata_task_ioctl - Handler for HDIO_DRIVE_TASK ioctl
301  *	@scsidev: Device to which we are issuing command
302  *	@arg: User provided data for issuing command
303  *
304  *	LOCKING:
305  *	Defined by the SCSI layer.  We don't really care.
306  *
307  *	RETURNS:
308  *	Zero on success, negative errno on error.
309  */
310 int ata_task_ioctl(struct scsi_device *scsidev, void __user *arg)
311 {
312 	int rc = 0;
313 	u8 scsi_cmd[MAX_COMMAND_SIZE];
314 	u8 args[7], *sensebuf = NULL;
315 	int cmd_result;
316 
317 	if (arg == NULL)
318 		return -EINVAL;
319 
320 	if (copy_from_user(args, arg, sizeof(args)))
321 		return -EFAULT;
322 
323 	sensebuf = kzalloc(SCSI_SENSE_BUFFERSIZE, GFP_NOIO);
324 	if (!sensebuf)
325 		return -ENOMEM;
326 
327 	memset(scsi_cmd, 0, sizeof(scsi_cmd));
328 	scsi_cmd[0]  = ATA_16;
329 	scsi_cmd[1]  = (3 << 1); /* Non-data */
330 	scsi_cmd[2]  = 0x20;     /* cc but no off.line or data xfer */
331 	scsi_cmd[4]  = args[1];
332 	scsi_cmd[6]  = args[2];
333 	scsi_cmd[8]  = args[3];
334 	scsi_cmd[10] = args[4];
335 	scsi_cmd[12] = args[5];
336 	scsi_cmd[13] = args[6] & 0x4f;
337 	scsi_cmd[14] = args[0];
338 
339 	/* Good values for timeout and retries?  Values below
340 	   from scsi_ioctl_send_command() for default case... */
341 	cmd_result = scsi_execute(scsidev, scsi_cmd, DMA_NONE, NULL, 0,
342 				sensebuf, (10*HZ), 5, 0);
343 
344 	if (driver_byte(cmd_result) == DRIVER_SENSE) {/* sense data available */
345 		u8 *desc = sensebuf + 8;
346 		cmd_result &= ~(0xFF<<24); /* DRIVER_SENSE is not an error */
347 
348 		/* If we set cc then ATA pass-through will cause a
349 		 * check condition even if no error. Filter that. */
350 		if (cmd_result & SAM_STAT_CHECK_CONDITION) {
351 			struct scsi_sense_hdr sshdr;
352 			scsi_normalize_sense(sensebuf, SCSI_SENSE_BUFFERSIZE,
353 						&sshdr);
354 			if (sshdr.sense_key==0 &&
355 				sshdr.asc==0 && sshdr.ascq==0)
356 				cmd_result &= ~SAM_STAT_CHECK_CONDITION;
357 		}
358 
359 		/* Send userspace ATA registers */
360 		if (sensebuf[0] == 0x72 &&	/* format is "descriptor" */
361 				desc[0] == 0x09) {/* code is "ATA Descriptor" */
362 			args[0] = desc[13];	/* status */
363 			args[1] = desc[3];	/* error */
364 			args[2] = desc[5];	/* sector count (0:7) */
365 			args[3] = desc[7];	/* lbal */
366 			args[4] = desc[9];	/* lbam */
367 			args[5] = desc[11];	/* lbah */
368 			args[6] = desc[12];	/* select */
369 			if (copy_to_user(arg, args, sizeof(args)))
370 				rc = -EFAULT;
371 		}
372 	}
373 
374 	if (cmd_result) {
375 		rc = -EIO;
376 		goto error;
377 	}
378 
379  error:
380 	kfree(sensebuf);
381 	return rc;
382 }
383 
384 int ata_scsi_ioctl(struct scsi_device *scsidev, int cmd, void __user *arg)
385 {
386 	int val = -EINVAL, rc = -EINVAL;
387 
388 	switch (cmd) {
389 	case ATA_IOC_GET_IO32:
390 		val = 0;
391 		if (copy_to_user(arg, &val, 1))
392 			return -EFAULT;
393 		return 0;
394 
395 	case ATA_IOC_SET_IO32:
396 		val = (unsigned long) arg;
397 		if (val != 0)
398 			return -EINVAL;
399 		return 0;
400 
401 	case HDIO_GET_IDENTITY:
402 		return ata_get_identity(scsidev, arg);
403 
404 	case HDIO_DRIVE_CMD:
405 		if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
406 			return -EACCES;
407 		return ata_cmd_ioctl(scsidev, arg);
408 
409 	case HDIO_DRIVE_TASK:
410 		if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
411 			return -EACCES;
412 		return ata_task_ioctl(scsidev, arg);
413 
414 	default:
415 		rc = -ENOTTY;
416 		break;
417 	}
418 
419 	return rc;
420 }
421 
422 /**
423  *	ata_scsi_qc_new - acquire new ata_queued_cmd reference
424  *	@dev: ATA device to which the new command is attached
425  *	@cmd: SCSI command that originated this ATA command
426  *	@done: SCSI command completion function
427  *
428  *	Obtain a reference to an unused ata_queued_cmd structure,
429  *	which is the basic libata structure representing a single
430  *	ATA command sent to the hardware.
431  *
432  *	If a command was available, fill in the SCSI-specific
433  *	portions of the structure with information on the
434  *	current command.
435  *
436  *	LOCKING:
437  *	spin_lock_irqsave(host lock)
438  *
439  *	RETURNS:
440  *	Command allocated, or %NULL if none available.
441  */
442 static struct ata_queued_cmd *ata_scsi_qc_new(struct ata_device *dev,
443 					      struct scsi_cmnd *cmd,
444 					      void (*done)(struct scsi_cmnd *))
445 {
446 	struct ata_queued_cmd *qc;
447 
448 	qc = ata_qc_new_init(dev);
449 	if (qc) {
450 		qc->scsicmd = cmd;
451 		qc->scsidone = done;
452 
453 		if (cmd->use_sg) {
454 			qc->__sg = (struct scatterlist *) cmd->request_buffer;
455 			qc->n_elem = cmd->use_sg;
456 		} else if (cmd->request_bufflen) {
457 			qc->__sg = &qc->sgent;
458 			qc->n_elem = 1;
459 		}
460 	} else {
461 		cmd->result = (DID_OK << 16) | (QUEUE_FULL << 1);
462 		done(cmd);
463 	}
464 
465 	return qc;
466 }
467 
468 /**
469  *	ata_dump_status - user friendly display of error info
470  *	@id: id of the port in question
471  *	@tf: ptr to filled out taskfile
472  *
473  *	Decode and dump the ATA error/status registers for the user so
474  *	that they have some idea what really happened at the non
475  *	make-believe layer.
476  *
477  *	LOCKING:
478  *	inherited from caller
479  */
480 static void ata_dump_status(unsigned id, struct ata_taskfile *tf)
481 {
482 	u8 stat = tf->command, err = tf->feature;
483 
484 	printk(KERN_WARNING "ata%u: status=0x%02x { ", id, stat);
485 	if (stat & ATA_BUSY) {
486 		printk("Busy }\n");	/* Data is not valid in this case */
487 	} else {
488 		if (stat & 0x40)	printk("DriveReady ");
489 		if (stat & 0x20)	printk("DeviceFault ");
490 		if (stat & 0x10)	printk("SeekComplete ");
491 		if (stat & 0x08)	printk("DataRequest ");
492 		if (stat & 0x04)	printk("CorrectedError ");
493 		if (stat & 0x02)	printk("Index ");
494 		if (stat & 0x01)	printk("Error ");
495 		printk("}\n");
496 
497 		if (err) {
498 			printk(KERN_WARNING "ata%u: error=0x%02x { ", id, err);
499 			if (err & 0x04)		printk("DriveStatusError ");
500 			if (err & 0x80) {
501 				if (err & 0x04)	printk("BadCRC ");
502 				else		printk("Sector ");
503 			}
504 			if (err & 0x40)		printk("UncorrectableError ");
505 			if (err & 0x10)		printk("SectorIdNotFound ");
506 			if (err & 0x02)		printk("TrackZeroNotFound ");
507 			if (err & 0x01)		printk("AddrMarkNotFound ");
508 			printk("}\n");
509 		}
510 	}
511 }
512 
513 /**
514  *	ata_to_sense_error - convert ATA error to SCSI error
515  *	@id: ATA device number
516  *	@drv_stat: value contained in ATA status register
517  *	@drv_err: value contained in ATA error register
518  *	@sk: the sense key we'll fill out
519  *	@asc: the additional sense code we'll fill out
520  *	@ascq: the additional sense code qualifier we'll fill out
521  *	@verbose: be verbose
522  *
523  *	Converts an ATA error into a SCSI error.  Fill out pointers to
524  *	SK, ASC, and ASCQ bytes for later use in fixed or descriptor
525  *	format sense blocks.
526  *
527  *	LOCKING:
528  *	spin_lock_irqsave(host lock)
529  */
530 static void ata_to_sense_error(unsigned id, u8 drv_stat, u8 drv_err, u8 *sk,
531 			       u8 *asc, u8 *ascq, int verbose)
532 {
533 	int i;
534 
535 	/* Based on the 3ware driver translation table */
536 	static const unsigned char sense_table[][4] = {
537 		/* BBD|ECC|ID|MAR */
538 		{0xd1, 		ABORTED_COMMAND, 0x00, 0x00}, 	// Device busy                  Aborted command
539 		/* BBD|ECC|ID */
540 		{0xd0,  	ABORTED_COMMAND, 0x00, 0x00}, 	// Device busy                  Aborted command
541 		/* ECC|MC|MARK */
542 		{0x61, 		HARDWARE_ERROR, 0x00, 0x00}, 	// Device fault                 Hardware error
543 		/* ICRC|ABRT */		/* NB: ICRC & !ABRT is BBD */
544 		{0x84, 		ABORTED_COMMAND, 0x47, 0x00}, 	// Data CRC error               SCSI parity error
545 		/* MC|ID|ABRT|TRK0|MARK */
546 		{0x37, 		NOT_READY, 0x04, 0x00}, 	// Unit offline                 Not ready
547 		/* MCR|MARK */
548 		{0x09, 		NOT_READY, 0x04, 0x00}, 	// Unrecovered disk error       Not ready
549 		/*  Bad address mark */
550 		{0x01, 		MEDIUM_ERROR, 0x13, 0x00}, 	// Address mark not found       Address mark not found for data field
551 		/* TRK0 */
552 		{0x02, 		HARDWARE_ERROR, 0x00, 0x00}, 	// Track 0 not found		  Hardware error
553 		/* Abort & !ICRC */
554 		{0x04, 		ABORTED_COMMAND, 0x00, 0x00}, 	// Aborted command              Aborted command
555 		/* Media change request */
556 		{0x08, 		NOT_READY, 0x04, 0x00}, 	// Media change request	  FIXME: faking offline
557 		/* SRV */
558 		{0x10, 		ABORTED_COMMAND, 0x14, 0x00}, 	// ID not found                 Recorded entity not found
559 		/* Media change */
560 		{0x08,  	NOT_READY, 0x04, 0x00}, 	// Media change		  FIXME: faking offline
561 		/* ECC */
562 		{0x40, 		MEDIUM_ERROR, 0x11, 0x04}, 	// Uncorrectable ECC error      Unrecovered read error
563 		/* BBD - block marked bad */
564 		{0x80, 		MEDIUM_ERROR, 0x11, 0x04}, 	// Block marked bad		  Medium error, unrecovered read error
565 		{0xFF, 0xFF, 0xFF, 0xFF}, // END mark
566 	};
567 	static const unsigned char stat_table[][4] = {
568 		/* Must be first because BUSY means no other bits valid */
569 		{0x80, 		ABORTED_COMMAND, 0x47, 0x00},	// Busy, fake parity for now
570 		{0x20, 		HARDWARE_ERROR,  0x00, 0x00}, 	// Device fault
571 		{0x08, 		ABORTED_COMMAND, 0x47, 0x00},	// Timed out in xfer, fake parity for now
572 		{0x04, 		RECOVERED_ERROR, 0x11, 0x00},	// Recovered ECC error	  Medium error, recovered
573 		{0xFF, 0xFF, 0xFF, 0xFF}, // END mark
574 	};
575 
576 	/*
577 	 *	Is this an error we can process/parse
578 	 */
579 	if (drv_stat & ATA_BUSY) {
580 		drv_err = 0;	/* Ignore the err bits, they're invalid */
581 	}
582 
583 	if (drv_err) {
584 		/* Look for drv_err */
585 		for (i = 0; sense_table[i][0] != 0xFF; i++) {
586 			/* Look for best matches first */
587 			if ((sense_table[i][0] & drv_err) ==
588 			    sense_table[i][0]) {
589 				*sk = sense_table[i][1];
590 				*asc = sense_table[i][2];
591 				*ascq = sense_table[i][3];
592 				goto translate_done;
593 			}
594 		}
595 		/* No immediate match */
596 		if (verbose)
597 			printk(KERN_WARNING "ata%u: no sense translation for "
598 			       "error 0x%02x\n", id, drv_err);
599 	}
600 
601 	/* Fall back to interpreting status bits */
602 	for (i = 0; stat_table[i][0] != 0xFF; i++) {
603 		if (stat_table[i][0] & drv_stat) {
604 			*sk = stat_table[i][1];
605 			*asc = stat_table[i][2];
606 			*ascq = stat_table[i][3];
607 			goto translate_done;
608 		}
609 	}
610 	/* No error?  Undecoded? */
611 	if (verbose)
612 		printk(KERN_WARNING "ata%u: no sense translation for "
613 		       "status: 0x%02x\n", id, drv_stat);
614 
615 	/* We need a sensible error return here, which is tricky, and one
616 	   that won't cause people to do things like return a disk wrongly */
617 	*sk = ABORTED_COMMAND;
618 	*asc = 0x00;
619 	*ascq = 0x00;
620 
621  translate_done:
622 	if (verbose)
623 		printk(KERN_ERR "ata%u: translated ATA stat/err 0x%02x/%02x "
624 		       "to SCSI SK/ASC/ASCQ 0x%x/%02x/%02x\n",
625 		       id, drv_stat, drv_err, *sk, *asc, *ascq);
626 	return;
627 }
628 
629 /*
630  *	ata_gen_passthru_sense - Generate check condition sense block.
631  *	@qc: Command that completed.
632  *
633  *	This function is specific to the ATA descriptor format sense
634  *	block specified for the ATA pass through commands.  Regardless
635  *	of whether the command errored or not, return a sense
636  *	block. Copy all controller registers into the sense
637  *	block. Clear sense key, ASC & ASCQ if there is no error.
638  *
639  *	LOCKING:
640  *	None.
641  */
642 static void ata_gen_passthru_sense(struct ata_queued_cmd *qc)
643 {
644 	struct scsi_cmnd *cmd = qc->scsicmd;
645 	struct ata_taskfile *tf = &qc->result_tf;
646 	unsigned char *sb = cmd->sense_buffer;
647 	unsigned char *desc = sb + 8;
648 	int verbose = qc->ap->ops->error_handler == NULL;
649 
650 	memset(sb, 0, SCSI_SENSE_BUFFERSIZE);
651 
652 	cmd->result = (DRIVER_SENSE << 24) | SAM_STAT_CHECK_CONDITION;
653 
654 	/*
655 	 * Use ata_to_sense_error() to map status register bits
656 	 * onto sense key, asc & ascq.
657 	 */
658 	if (qc->err_mask ||
659 	    tf->command & (ATA_BUSY | ATA_DF | ATA_ERR | ATA_DRQ)) {
660 		ata_to_sense_error(qc->ap->print_id, tf->command, tf->feature,
661 				   &sb[1], &sb[2], &sb[3], verbose);
662 		sb[1] &= 0x0f;
663 	}
664 
665 	/*
666 	 * Sense data is current and format is descriptor.
667 	 */
668 	sb[0] = 0x72;
669 
670 	desc[0] = 0x09;
671 
672 	/* set length of additional sense data */
673 	sb[7] = 14;
674 	desc[1] = 12;
675 
676 	/*
677 	 * Copy registers into sense buffer.
678 	 */
679 	desc[2] = 0x00;
680 	desc[3] = tf->feature;	/* == error reg */
681 	desc[5] = tf->nsect;
682 	desc[7] = tf->lbal;
683 	desc[9] = tf->lbam;
684 	desc[11] = tf->lbah;
685 	desc[12] = tf->device;
686 	desc[13] = tf->command; /* == status reg */
687 
688 	/*
689 	 * Fill in Extend bit, and the high order bytes
690 	 * if applicable.
691 	 */
692 	if (tf->flags & ATA_TFLAG_LBA48) {
693 		desc[2] |= 0x01;
694 		desc[4] = tf->hob_nsect;
695 		desc[6] = tf->hob_lbal;
696 		desc[8] = tf->hob_lbam;
697 		desc[10] = tf->hob_lbah;
698 	}
699 }
700 
701 /**
702  *	ata_gen_ata_sense - generate a SCSI fixed sense block
703  *	@qc: Command that we are erroring out
704  *
705  *	Generate sense block for a failed ATA command @qc.  Descriptor
706  *	format is used to accomodate LBA48 block address.
707  *
708  *	LOCKING:
709  *	None.
710  */
711 static void ata_gen_ata_sense(struct ata_queued_cmd *qc)
712 {
713 	struct ata_device *dev = qc->dev;
714 	struct scsi_cmnd *cmd = qc->scsicmd;
715 	struct ata_taskfile *tf = &qc->result_tf;
716 	unsigned char *sb = cmd->sense_buffer;
717 	unsigned char *desc = sb + 8;
718 	int verbose = qc->ap->ops->error_handler == NULL;
719 	u64 block;
720 
721 	memset(sb, 0, SCSI_SENSE_BUFFERSIZE);
722 
723 	cmd->result = (DRIVER_SENSE << 24) | SAM_STAT_CHECK_CONDITION;
724 
725 	/* sense data is current and format is descriptor */
726 	sb[0] = 0x72;
727 
728 	/* Use ata_to_sense_error() to map status register bits
729 	 * onto sense key, asc & ascq.
730 	 */
731 	if (qc->err_mask ||
732 	    tf->command & (ATA_BUSY | ATA_DF | ATA_ERR | ATA_DRQ)) {
733 		ata_to_sense_error(qc->ap->print_id, tf->command, tf->feature,
734 				   &sb[1], &sb[2], &sb[3], verbose);
735 		sb[1] &= 0x0f;
736 	}
737 
738 	block = ata_tf_read_block(&qc->result_tf, dev);
739 
740 	/* information sense data descriptor */
741 	sb[7] = 12;
742 	desc[0] = 0x00;
743 	desc[1] = 10;
744 
745 	desc[2] |= 0x80;	/* valid */
746 	desc[6] = block >> 40;
747 	desc[7] = block >> 32;
748 	desc[8] = block >> 24;
749 	desc[9] = block >> 16;
750 	desc[10] = block >> 8;
751 	desc[11] = block;
752 }
753 
754 static void ata_scsi_sdev_config(struct scsi_device *sdev)
755 {
756 	sdev->use_10_for_rw = 1;
757 	sdev->use_10_for_ms = 1;
758 }
759 
760 static void ata_scsi_dev_config(struct scsi_device *sdev,
761 				struct ata_device *dev)
762 {
763 	/* configure max sectors */
764 	blk_queue_max_sectors(sdev->request_queue, dev->max_sectors);
765 
766 	/* SATA DMA transfers must be multiples of 4 byte, so
767 	 * we need to pad ATAPI transfers using an extra sg.
768 	 * Decrement max hw segments accordingly.
769 	 */
770 	if (dev->class == ATA_DEV_ATAPI) {
771 		request_queue_t *q = sdev->request_queue;
772 		blk_queue_max_hw_segments(q, q->max_hw_segments - 1);
773 	}
774 
775 	if (dev->flags & ATA_DFLAG_NCQ) {
776 		int depth;
777 
778 		depth = min(sdev->host->can_queue, ata_id_queue_depth(dev->id));
779 		depth = min(ATA_MAX_QUEUE - 1, depth);
780 		scsi_adjust_queue_depth(sdev, MSG_SIMPLE_TAG, depth);
781 	}
782 }
783 
784 /**
785  *	ata_scsi_slave_config - Set SCSI device attributes
786  *	@sdev: SCSI device to examine
787  *
788  *	This is called before we actually start reading
789  *	and writing to the device, to configure certain
790  *	SCSI mid-layer behaviors.
791  *
792  *	LOCKING:
793  *	Defined by SCSI layer.  We don't really care.
794  */
795 
796 int ata_scsi_slave_config(struct scsi_device *sdev)
797 {
798 	struct ata_port *ap = ata_shost_to_port(sdev->host);
799 	struct ata_device *dev = __ata_scsi_find_dev(ap, sdev);
800 
801 	ata_scsi_sdev_config(sdev);
802 
803 	blk_queue_max_phys_segments(sdev->request_queue, LIBATA_MAX_PRD);
804 
805 	sdev->manage_start_stop = 1;
806 
807 	if (dev)
808 		ata_scsi_dev_config(sdev, dev);
809 
810 	return 0;	/* scsi layer doesn't check return value, sigh */
811 }
812 
813 /**
814  *	ata_scsi_slave_destroy - SCSI device is about to be destroyed
815  *	@sdev: SCSI device to be destroyed
816  *
817  *	@sdev is about to be destroyed for hot/warm unplugging.  If
818  *	this unplugging was initiated by libata as indicated by NULL
819  *	dev->sdev, this function doesn't have to do anything.
820  *	Otherwise, SCSI layer initiated warm-unplug is in progress.
821  *	Clear dev->sdev, schedule the device for ATA detach and invoke
822  *	EH.
823  *
824  *	LOCKING:
825  *	Defined by SCSI layer.  We don't really care.
826  */
827 void ata_scsi_slave_destroy(struct scsi_device *sdev)
828 {
829 	struct ata_port *ap = ata_shost_to_port(sdev->host);
830 	unsigned long flags;
831 	struct ata_device *dev;
832 
833 	if (!ap->ops->error_handler)
834 		return;
835 
836 	spin_lock_irqsave(ap->lock, flags);
837 	dev = __ata_scsi_find_dev(ap, sdev);
838 	if (dev && dev->sdev) {
839 		/* SCSI device already in CANCEL state, no need to offline it */
840 		dev->sdev = NULL;
841 		dev->flags |= ATA_DFLAG_DETACH;
842 		ata_port_schedule_eh(ap);
843 	}
844 	spin_unlock_irqrestore(ap->lock, flags);
845 }
846 
847 /**
848  *	ata_scsi_change_queue_depth - SCSI callback for queue depth config
849  *	@sdev: SCSI device to configure queue depth for
850  *	@queue_depth: new queue depth
851  *
852  *	This is libata standard hostt->change_queue_depth callback.
853  *	SCSI will call into this callback when user tries to set queue
854  *	depth via sysfs.
855  *
856  *	LOCKING:
857  *	SCSI layer (we don't care)
858  *
859  *	RETURNS:
860  *	Newly configured queue depth.
861  */
862 int ata_scsi_change_queue_depth(struct scsi_device *sdev, int queue_depth)
863 {
864 	struct ata_port *ap = ata_shost_to_port(sdev->host);
865 	struct ata_device *dev;
866 	unsigned long flags;
867 
868 	if (queue_depth < 1 || queue_depth == sdev->queue_depth)
869 		return sdev->queue_depth;
870 
871 	dev = ata_scsi_find_dev(ap, sdev);
872 	if (!dev || !ata_dev_enabled(dev))
873 		return sdev->queue_depth;
874 
875 	/* NCQ enabled? */
876 	spin_lock_irqsave(ap->lock, flags);
877 	dev->flags &= ~ATA_DFLAG_NCQ_OFF;
878 	if (queue_depth == 1 || !ata_ncq_enabled(dev)) {
879 		dev->flags |= ATA_DFLAG_NCQ_OFF;
880 		queue_depth = 1;
881 	}
882 	spin_unlock_irqrestore(ap->lock, flags);
883 
884 	/* limit and apply queue depth */
885 	queue_depth = min(queue_depth, sdev->host->can_queue);
886 	queue_depth = min(queue_depth, ata_id_queue_depth(dev->id));
887 	queue_depth = min(queue_depth, ATA_MAX_QUEUE - 1);
888 
889 	if (sdev->queue_depth == queue_depth)
890 		return -EINVAL;
891 
892 	scsi_adjust_queue_depth(sdev, MSG_SIMPLE_TAG, queue_depth);
893 	return queue_depth;
894 }
895 
896 /* XXX: for spindown warning */
897 static void ata_delayed_done_timerfn(unsigned long arg)
898 {
899 	struct scsi_cmnd *scmd = (void *)arg;
900 
901 	scmd->scsi_done(scmd);
902 }
903 
904 /* XXX: for spindown warning */
905 static void ata_delayed_done(struct scsi_cmnd *scmd)
906 {
907 	static struct timer_list timer;
908 
909 	setup_timer(&timer, ata_delayed_done_timerfn, (unsigned long)scmd);
910 	mod_timer(&timer, jiffies + 5 * HZ);
911 }
912 
913 /**
914  *	ata_scsi_start_stop_xlat - Translate SCSI START STOP UNIT command
915  *	@qc: Storage for translated ATA taskfile
916  *
917  *	Sets up an ATA taskfile to issue STANDBY (to stop) or READ VERIFY
918  *	(to start). Perhaps these commands should be preceded by
919  *	CHECK POWER MODE to see what power mode the device is already in.
920  *	[See SAT revision 5 at www.t10.org]
921  *
922  *	LOCKING:
923  *	spin_lock_irqsave(host lock)
924  *
925  *	RETURNS:
926  *	Zero on success, non-zero on error.
927  */
928 static unsigned int ata_scsi_start_stop_xlat(struct ata_queued_cmd *qc)
929 {
930 	struct scsi_cmnd *scmd = qc->scsicmd;
931 	struct ata_taskfile *tf = &qc->tf;
932 	const u8 *cdb = scmd->cmnd;
933 
934 	if (scmd->cmd_len < 5)
935 		goto invalid_fld;
936 
937 	tf->flags |= ATA_TFLAG_DEVICE | ATA_TFLAG_ISADDR;
938 	tf->protocol = ATA_PROT_NODATA;
939 	if (cdb[1] & 0x1) {
940 		;	/* ignore IMMED bit, violates sat-r05 */
941 	}
942 	if (cdb[4] & 0x2)
943 		goto invalid_fld;       /* LOEJ bit set not supported */
944 	if (((cdb[4] >> 4) & 0xf) != 0)
945 		goto invalid_fld;       /* power conditions not supported */
946 	if (cdb[4] & 0x1) {
947 		tf->nsect = 1;	/* 1 sector, lba=0 */
948 
949 		if (qc->dev->flags & ATA_DFLAG_LBA) {
950 			tf->flags |= ATA_TFLAG_LBA;
951 
952 			tf->lbah = 0x0;
953 			tf->lbam = 0x0;
954 			tf->lbal = 0x0;
955 			tf->device |= ATA_LBA;
956 		} else {
957 			/* CHS */
958 			tf->lbal = 0x1; /* sect */
959 			tf->lbam = 0x0; /* cyl low */
960 			tf->lbah = 0x0; /* cyl high */
961 		}
962 
963 		tf->command = ATA_CMD_VERIFY;	/* READ VERIFY */
964 	} else {
965 		/* XXX: This is for backward compatibility, will be
966 		 * removed.  Read Documentation/feature-removal-schedule.txt
967 		 * for more info.
968 		 */
969 		if ((qc->dev->flags & ATA_DFLAG_SPUNDOWN) &&
970 		    (system_state == SYSTEM_HALT ||
971 		     system_state == SYSTEM_POWER_OFF)) {
972 			static unsigned long warned = 0;
973 
974 			if (!test_and_set_bit(0, &warned)) {
975 				ata_dev_printk(qc->dev, KERN_WARNING,
976 					"DISK MIGHT NOT BE SPUN DOWN PROPERLY. "
977 					"UPDATE SHUTDOWN UTILITY\n");
978 				ata_dev_printk(qc->dev, KERN_WARNING,
979 					"For more info, visit "
980 					"http://linux-ata.org/shutdown.html\n");
981 
982 				/* ->scsi_done is not used, use it for
983 				 * delayed completion.
984 				 */
985 				scmd->scsi_done = qc->scsidone;
986 				qc->scsidone = ata_delayed_done;
987 			}
988 			scmd->result = SAM_STAT_GOOD;
989 			return 1;
990 		}
991 
992 		/* Issue ATA STANDBY IMMEDIATE command */
993 		tf->command = ATA_CMD_STANDBYNOW1;
994 	}
995 
996 	/*
997 	 * Standby and Idle condition timers could be implemented but that
998 	 * would require libata to implement the Power condition mode page
999 	 * and allow the user to change it. Changing mode pages requires
1000 	 * MODE SELECT to be implemented.
1001 	 */
1002 
1003 	return 0;
1004 
1005 invalid_fld:
1006 	ata_scsi_set_sense(scmd, ILLEGAL_REQUEST, 0x24, 0x0);
1007 	/* "Invalid field in cbd" */
1008 	return 1;
1009 }
1010 
1011 
1012 /**
1013  *	ata_scsi_flush_xlat - Translate SCSI SYNCHRONIZE CACHE command
1014  *	@qc: Storage for translated ATA taskfile
1015  *
1016  *	Sets up an ATA taskfile to issue FLUSH CACHE or
1017  *	FLUSH CACHE EXT.
1018  *
1019  *	LOCKING:
1020  *	spin_lock_irqsave(host lock)
1021  *
1022  *	RETURNS:
1023  *	Zero on success, non-zero on error.
1024  */
1025 static unsigned int ata_scsi_flush_xlat(struct ata_queued_cmd *qc)
1026 {
1027 	struct ata_taskfile *tf = &qc->tf;
1028 
1029 	tf->flags |= ATA_TFLAG_DEVICE;
1030 	tf->protocol = ATA_PROT_NODATA;
1031 
1032 	if (qc->dev->flags & ATA_DFLAG_FLUSH_EXT)
1033 		tf->command = ATA_CMD_FLUSH_EXT;
1034 	else
1035 		tf->command = ATA_CMD_FLUSH;
1036 
1037 	return 0;
1038 }
1039 
1040 /**
1041  *	scsi_6_lba_len - Get LBA and transfer length
1042  *	@cdb: SCSI command to translate
1043  *
1044  *	Calculate LBA and transfer length for 6-byte commands.
1045  *
1046  *	RETURNS:
1047  *	@plba: the LBA
1048  *	@plen: the transfer length
1049  */
1050 static void scsi_6_lba_len(const u8 *cdb, u64 *plba, u32 *plen)
1051 {
1052 	u64 lba = 0;
1053 	u32 len;
1054 
1055 	VPRINTK("six-byte command\n");
1056 
1057 	lba |= ((u64)(cdb[1] & 0x1f)) << 16;
1058 	lba |= ((u64)cdb[2]) << 8;
1059 	lba |= ((u64)cdb[3]);
1060 
1061 	len = cdb[4];
1062 
1063 	*plba = lba;
1064 	*plen = len;
1065 }
1066 
1067 /**
1068  *	scsi_10_lba_len - Get LBA and transfer length
1069  *	@cdb: SCSI command to translate
1070  *
1071  *	Calculate LBA and transfer length for 10-byte commands.
1072  *
1073  *	RETURNS:
1074  *	@plba: the LBA
1075  *	@plen: the transfer length
1076  */
1077 static void scsi_10_lba_len(const u8 *cdb, u64 *plba, u32 *plen)
1078 {
1079 	u64 lba = 0;
1080 	u32 len = 0;
1081 
1082 	VPRINTK("ten-byte command\n");
1083 
1084 	lba |= ((u64)cdb[2]) << 24;
1085 	lba |= ((u64)cdb[3]) << 16;
1086 	lba |= ((u64)cdb[4]) << 8;
1087 	lba |= ((u64)cdb[5]);
1088 
1089 	len |= ((u32)cdb[7]) << 8;
1090 	len |= ((u32)cdb[8]);
1091 
1092 	*plba = lba;
1093 	*plen = len;
1094 }
1095 
1096 /**
1097  *	scsi_16_lba_len - Get LBA and transfer length
1098  *	@cdb: SCSI command to translate
1099  *
1100  *	Calculate LBA and transfer length for 16-byte commands.
1101  *
1102  *	RETURNS:
1103  *	@plba: the LBA
1104  *	@plen: the transfer length
1105  */
1106 static void scsi_16_lba_len(const u8 *cdb, u64 *plba, u32 *plen)
1107 {
1108 	u64 lba = 0;
1109 	u32 len = 0;
1110 
1111 	VPRINTK("sixteen-byte command\n");
1112 
1113 	lba |= ((u64)cdb[2]) << 56;
1114 	lba |= ((u64)cdb[3]) << 48;
1115 	lba |= ((u64)cdb[4]) << 40;
1116 	lba |= ((u64)cdb[5]) << 32;
1117 	lba |= ((u64)cdb[6]) << 24;
1118 	lba |= ((u64)cdb[7]) << 16;
1119 	lba |= ((u64)cdb[8]) << 8;
1120 	lba |= ((u64)cdb[9]);
1121 
1122 	len |= ((u32)cdb[10]) << 24;
1123 	len |= ((u32)cdb[11]) << 16;
1124 	len |= ((u32)cdb[12]) << 8;
1125 	len |= ((u32)cdb[13]);
1126 
1127 	*plba = lba;
1128 	*plen = len;
1129 }
1130 
1131 /**
1132  *	ata_scsi_verify_xlat - Translate SCSI VERIFY command into an ATA one
1133  *	@qc: Storage for translated ATA taskfile
1134  *
1135  *	Converts SCSI VERIFY command to an ATA READ VERIFY command.
1136  *
1137  *	LOCKING:
1138  *	spin_lock_irqsave(host lock)
1139  *
1140  *	RETURNS:
1141  *	Zero on success, non-zero on error.
1142  */
1143 static unsigned int ata_scsi_verify_xlat(struct ata_queued_cmd *qc)
1144 {
1145 	struct scsi_cmnd *scmd = qc->scsicmd;
1146 	struct ata_taskfile *tf = &qc->tf;
1147 	struct ata_device *dev = qc->dev;
1148 	u64 dev_sectors = qc->dev->n_sectors;
1149 	const u8 *cdb = scmd->cmnd;
1150 	u64 block;
1151 	u32 n_block;
1152 
1153 	tf->flags |= ATA_TFLAG_ISADDR | ATA_TFLAG_DEVICE;
1154 	tf->protocol = ATA_PROT_NODATA;
1155 
1156 	if (cdb[0] == VERIFY) {
1157 		if (scmd->cmd_len < 10)
1158 			goto invalid_fld;
1159 		scsi_10_lba_len(cdb, &block, &n_block);
1160 	} else if (cdb[0] == VERIFY_16) {
1161 		if (scmd->cmd_len < 16)
1162 			goto invalid_fld;
1163 		scsi_16_lba_len(cdb, &block, &n_block);
1164 	} else
1165 		goto invalid_fld;
1166 
1167 	if (!n_block)
1168 		goto nothing_to_do;
1169 	if (block >= dev_sectors)
1170 		goto out_of_range;
1171 	if ((block + n_block) > dev_sectors)
1172 		goto out_of_range;
1173 
1174 	if (dev->flags & ATA_DFLAG_LBA) {
1175 		tf->flags |= ATA_TFLAG_LBA;
1176 
1177 		if (lba_28_ok(block, n_block)) {
1178 			/* use LBA28 */
1179 			tf->command = ATA_CMD_VERIFY;
1180 			tf->device |= (block >> 24) & 0xf;
1181 		} else if (lba_48_ok(block, n_block)) {
1182 			if (!(dev->flags & ATA_DFLAG_LBA48))
1183 				goto out_of_range;
1184 
1185 			/* use LBA48 */
1186 			tf->flags |= ATA_TFLAG_LBA48;
1187 			tf->command = ATA_CMD_VERIFY_EXT;
1188 
1189 			tf->hob_nsect = (n_block >> 8) & 0xff;
1190 
1191 			tf->hob_lbah = (block >> 40) & 0xff;
1192 			tf->hob_lbam = (block >> 32) & 0xff;
1193 			tf->hob_lbal = (block >> 24) & 0xff;
1194 		} else
1195 			/* request too large even for LBA48 */
1196 			goto out_of_range;
1197 
1198 		tf->nsect = n_block & 0xff;
1199 
1200 		tf->lbah = (block >> 16) & 0xff;
1201 		tf->lbam = (block >> 8) & 0xff;
1202 		tf->lbal = block & 0xff;
1203 
1204 		tf->device |= ATA_LBA;
1205 	} else {
1206 		/* CHS */
1207 		u32 sect, head, cyl, track;
1208 
1209 		if (!lba_28_ok(block, n_block))
1210 			goto out_of_range;
1211 
1212 		/* Convert LBA to CHS */
1213 		track = (u32)block / dev->sectors;
1214 		cyl   = track / dev->heads;
1215 		head  = track % dev->heads;
1216 		sect  = (u32)block % dev->sectors + 1;
1217 
1218 		DPRINTK("block %u track %u cyl %u head %u sect %u\n",
1219 			(u32)block, track, cyl, head, sect);
1220 
1221 		/* Check whether the converted CHS can fit.
1222 		   Cylinder: 0-65535
1223 		   Head: 0-15
1224 		   Sector: 1-255*/
1225 		if ((cyl >> 16) || (head >> 4) || (sect >> 8) || (!sect))
1226 			goto out_of_range;
1227 
1228 		tf->command = ATA_CMD_VERIFY;
1229 		tf->nsect = n_block & 0xff; /* Sector count 0 means 256 sectors */
1230 		tf->lbal = sect;
1231 		tf->lbam = cyl;
1232 		tf->lbah = cyl >> 8;
1233 		tf->device |= head;
1234 	}
1235 
1236 	return 0;
1237 
1238 invalid_fld:
1239 	ata_scsi_set_sense(scmd, ILLEGAL_REQUEST, 0x24, 0x0);
1240 	/* "Invalid field in cbd" */
1241 	return 1;
1242 
1243 out_of_range:
1244 	ata_scsi_set_sense(scmd, ILLEGAL_REQUEST, 0x21, 0x0);
1245 	/* "Logical Block Address out of range" */
1246 	return 1;
1247 
1248 nothing_to_do:
1249 	scmd->result = SAM_STAT_GOOD;
1250 	return 1;
1251 }
1252 
1253 /**
1254  *	ata_scsi_rw_xlat - Translate SCSI r/w command into an ATA one
1255  *	@qc: Storage for translated ATA taskfile
1256  *
1257  *	Converts any of six SCSI read/write commands into the
1258  *	ATA counterpart, including starting sector (LBA),
1259  *	sector count, and taking into account the device's LBA48
1260  *	support.
1261  *
1262  *	Commands %READ_6, %READ_10, %READ_16, %WRITE_6, %WRITE_10, and
1263  *	%WRITE_16 are currently supported.
1264  *
1265  *	LOCKING:
1266  *	spin_lock_irqsave(host lock)
1267  *
1268  *	RETURNS:
1269  *	Zero on success, non-zero on error.
1270  */
1271 static unsigned int ata_scsi_rw_xlat(struct ata_queued_cmd *qc)
1272 {
1273 	struct scsi_cmnd *scmd = qc->scsicmd;
1274 	const u8 *cdb = scmd->cmnd;
1275 	unsigned int tf_flags = 0;
1276 	u64 block;
1277 	u32 n_block;
1278 	int rc;
1279 
1280 	if (cdb[0] == WRITE_10 || cdb[0] == WRITE_6 || cdb[0] == WRITE_16)
1281 		tf_flags |= ATA_TFLAG_WRITE;
1282 
1283 	/* Calculate the SCSI LBA, transfer length and FUA. */
1284 	switch (cdb[0]) {
1285 	case READ_10:
1286 	case WRITE_10:
1287 		if (unlikely(scmd->cmd_len < 10))
1288 			goto invalid_fld;
1289 		scsi_10_lba_len(cdb, &block, &n_block);
1290 		if (unlikely(cdb[1] & (1 << 3)))
1291 			tf_flags |= ATA_TFLAG_FUA;
1292 		break;
1293 	case READ_6:
1294 	case WRITE_6:
1295 		if (unlikely(scmd->cmd_len < 6))
1296 			goto invalid_fld;
1297 		scsi_6_lba_len(cdb, &block, &n_block);
1298 
1299 		/* for 6-byte r/w commands, transfer length 0
1300 		 * means 256 blocks of data, not 0 block.
1301 		 */
1302 		if (!n_block)
1303 			n_block = 256;
1304 		break;
1305 	case READ_16:
1306 	case WRITE_16:
1307 		if (unlikely(scmd->cmd_len < 16))
1308 			goto invalid_fld;
1309 		scsi_16_lba_len(cdb, &block, &n_block);
1310 		if (unlikely(cdb[1] & (1 << 3)))
1311 			tf_flags |= ATA_TFLAG_FUA;
1312 		break;
1313 	default:
1314 		DPRINTK("no-byte command\n");
1315 		goto invalid_fld;
1316 	}
1317 
1318 	/* Check and compose ATA command */
1319 	if (!n_block)
1320 		/* For 10-byte and 16-byte SCSI R/W commands, transfer
1321 		 * length 0 means transfer 0 block of data.
1322 		 * However, for ATA R/W commands, sector count 0 means
1323 		 * 256 or 65536 sectors, not 0 sectors as in SCSI.
1324 		 *
1325 		 * WARNING: one or two older ATA drives treat 0 as 0...
1326 		 */
1327 		goto nothing_to_do;
1328 
1329 	qc->flags |= ATA_QCFLAG_IO;
1330 	qc->nbytes = n_block * ATA_SECT_SIZE;
1331 
1332 	rc = ata_build_rw_tf(&qc->tf, qc->dev, block, n_block, tf_flags,
1333 			     qc->tag);
1334 	if (likely(rc == 0))
1335 		return 0;
1336 
1337 	if (rc == -ERANGE)
1338 		goto out_of_range;
1339 	/* treat all other errors as -EINVAL, fall through */
1340 invalid_fld:
1341 	ata_scsi_set_sense(scmd, ILLEGAL_REQUEST, 0x24, 0x0);
1342 	/* "Invalid field in cbd" */
1343 	return 1;
1344 
1345 out_of_range:
1346 	ata_scsi_set_sense(scmd, ILLEGAL_REQUEST, 0x21, 0x0);
1347 	/* "Logical Block Address out of range" */
1348 	return 1;
1349 
1350 nothing_to_do:
1351 	scmd->result = SAM_STAT_GOOD;
1352 	return 1;
1353 }
1354 
1355 static void ata_scsi_qc_complete(struct ata_queued_cmd *qc)
1356 {
1357 	struct ata_port *ap = qc->ap;
1358 	struct scsi_cmnd *cmd = qc->scsicmd;
1359 	u8 *cdb = cmd->cmnd;
1360  	int need_sense = (qc->err_mask != 0);
1361 
1362 	/* We snoop the SET_FEATURES - Write Cache ON/OFF command, and
1363 	 * schedule EH_REVALIDATE operation to update the IDENTIFY DEVICE
1364 	 * cache
1365 	 */
1366 	if (ap->ops->error_handler && !need_sense) {
1367 		switch (qc->tf.command) {
1368 		case ATA_CMD_SET_FEATURES:
1369 			if ((qc->tf.feature == SETFEATURES_WC_ON) ||
1370 			    (qc->tf.feature == SETFEATURES_WC_OFF)) {
1371 				ap->eh_info.action |= ATA_EH_REVALIDATE;
1372 				ata_port_schedule_eh(ap);
1373 			}
1374 			break;
1375 
1376 		case ATA_CMD_INIT_DEV_PARAMS: /* CHS translation changed */
1377 		case ATA_CMD_SET_MULTI: /* multi_count changed */
1378 			ap->eh_info.action |= ATA_EH_REVALIDATE;
1379 			ata_port_schedule_eh(ap);
1380 			break;
1381 		}
1382 	}
1383 
1384 	/* For ATA pass thru (SAT) commands, generate a sense block if
1385 	 * user mandated it or if there's an error.  Note that if we
1386 	 * generate because the user forced us to, a check condition
1387 	 * is generated and the ATA register values are returned
1388 	 * whether the command completed successfully or not. If there
1389 	 * was no error, SK, ASC and ASCQ will all be zero.
1390 	 */
1391 	if (((cdb[0] == ATA_16) || (cdb[0] == ATA_12)) &&
1392  	    ((cdb[2] & 0x20) || need_sense)) {
1393 		ata_gen_passthru_sense(qc);
1394 	} else {
1395 		if (!need_sense) {
1396 			cmd->result = SAM_STAT_GOOD;
1397 		} else {
1398 			/* TODO: decide which descriptor format to use
1399 			 * for 48b LBA devices and call that here
1400 			 * instead of the fixed desc, which is only
1401 			 * good for smaller LBA (and maybe CHS?)
1402 			 * devices.
1403 			 */
1404 			ata_gen_ata_sense(qc);
1405 		}
1406 	}
1407 
1408 	/* XXX: track spindown state for spindown skipping and warning */
1409 	if (unlikely(qc->tf.command == ATA_CMD_STANDBY ||
1410 		     qc->tf.command == ATA_CMD_STANDBYNOW1))
1411 		qc->dev->flags |= ATA_DFLAG_SPUNDOWN;
1412 	else if (likely(system_state != SYSTEM_HALT &&
1413 			system_state != SYSTEM_POWER_OFF))
1414 		qc->dev->flags &= ~ATA_DFLAG_SPUNDOWN;
1415 
1416 	if (need_sense && !ap->ops->error_handler)
1417 		ata_dump_status(ap->print_id, &qc->result_tf);
1418 
1419 	qc->scsidone(cmd);
1420 
1421 	ata_qc_free(qc);
1422 }
1423 
1424 /**
1425  *	ata_scmd_need_defer - Check whether we need to defer scmd
1426  *	@dev: ATA device to which the command is addressed
1427  *	@is_io: Is the command IO (and thus possibly NCQ)?
1428  *
1429  *	NCQ and non-NCQ commands cannot run together.  As upper layer
1430  *	only knows the queue depth, we are responsible for maintaining
1431  *	exclusion.  This function checks whether a new command can be
1432  *	issued to @dev.
1433  *
1434  *	LOCKING:
1435  *	spin_lock_irqsave(host lock)
1436  *
1437  *	RETURNS:
1438  *	1 if deferring is needed, 0 otherwise.
1439  */
1440 static int ata_scmd_need_defer(struct ata_device *dev, int is_io)
1441 {
1442 	struct ata_port *ap = dev->ap;
1443 	int is_ncq = is_io && ata_ncq_enabled(dev);
1444 
1445 	if (is_ncq) {
1446 		if (!ata_tag_valid(ap->active_tag))
1447 			return 0;
1448 	} else {
1449 		if (!ata_tag_valid(ap->active_tag) && !ap->sactive)
1450 			return 0;
1451 	}
1452 	return 1;
1453 }
1454 
1455 /**
1456  *	ata_scsi_translate - Translate then issue SCSI command to ATA device
1457  *	@dev: ATA device to which the command is addressed
1458  *	@cmd: SCSI command to execute
1459  *	@done: SCSI command completion function
1460  *	@xlat_func: Actor which translates @cmd to an ATA taskfile
1461  *
1462  *	Our ->queuecommand() function has decided that the SCSI
1463  *	command issued can be directly translated into an ATA
1464  *	command, rather than handled internally.
1465  *
1466  *	This function sets up an ata_queued_cmd structure for the
1467  *	SCSI command, and sends that ata_queued_cmd to the hardware.
1468  *
1469  *	The xlat_func argument (actor) returns 0 if ready to execute
1470  *	ATA command, else 1 to finish translation. If 1 is returned
1471  *	then cmd->result (and possibly cmd->sense_buffer) are assumed
1472  *	to be set reflecting an error condition or clean (early)
1473  *	termination.
1474  *
1475  *	LOCKING:
1476  *	spin_lock_irqsave(host lock)
1477  *
1478  *	RETURNS:
1479  *	0 on success, SCSI_ML_QUEUE_DEVICE_BUSY if the command
1480  *	needs to be deferred.
1481  */
1482 static int ata_scsi_translate(struct ata_device *dev, struct scsi_cmnd *cmd,
1483 			      void (*done)(struct scsi_cmnd *),
1484 			      ata_xlat_func_t xlat_func)
1485 {
1486 	struct ata_queued_cmd *qc;
1487 	int is_io = xlat_func == ata_scsi_rw_xlat;
1488 
1489 	VPRINTK("ENTER\n");
1490 
1491 	if (unlikely(ata_scmd_need_defer(dev, is_io)))
1492 		goto defer;
1493 
1494 	qc = ata_scsi_qc_new(dev, cmd, done);
1495 	if (!qc)
1496 		goto err_mem;
1497 
1498 	/* data is present; dma-map it */
1499 	if (cmd->sc_data_direction == DMA_FROM_DEVICE ||
1500 	    cmd->sc_data_direction == DMA_TO_DEVICE) {
1501 		if (unlikely(cmd->request_bufflen < 1)) {
1502 			ata_dev_printk(dev, KERN_WARNING,
1503 				       "WARNING: zero len r/w req\n");
1504 			goto err_did;
1505 		}
1506 
1507 		if (cmd->use_sg)
1508 			ata_sg_init(qc, cmd->request_buffer, cmd->use_sg);
1509 		else
1510 			ata_sg_init_one(qc, cmd->request_buffer,
1511 					cmd->request_bufflen);
1512 
1513 		qc->dma_dir = cmd->sc_data_direction;
1514 	}
1515 
1516 	qc->complete_fn = ata_scsi_qc_complete;
1517 
1518 	if (xlat_func(qc))
1519 		goto early_finish;
1520 
1521 	/* select device, send command to hardware */
1522 	ata_qc_issue(qc);
1523 
1524 	VPRINTK("EXIT\n");
1525 	return 0;
1526 
1527 early_finish:
1528         ata_qc_free(qc);
1529 	qc->scsidone(cmd);
1530 	DPRINTK("EXIT - early finish (good or error)\n");
1531 	return 0;
1532 
1533 err_did:
1534 	ata_qc_free(qc);
1535 	cmd->result = (DID_ERROR << 16);
1536 	qc->scsidone(cmd);
1537 err_mem:
1538 	DPRINTK("EXIT - internal\n");
1539 	return 0;
1540 
1541 defer:
1542 	DPRINTK("EXIT - defer\n");
1543 	return SCSI_MLQUEUE_DEVICE_BUSY;
1544 }
1545 
1546 /**
1547  *	ata_scsi_rbuf_get - Map response buffer.
1548  *	@cmd: SCSI command containing buffer to be mapped.
1549  *	@buf_out: Pointer to mapped area.
1550  *
1551  *	Maps buffer contained within SCSI command @cmd.
1552  *
1553  *	LOCKING:
1554  *	spin_lock_irqsave(host lock)
1555  *
1556  *	RETURNS:
1557  *	Length of response buffer.
1558  */
1559 
1560 static unsigned int ata_scsi_rbuf_get(struct scsi_cmnd *cmd, u8 **buf_out)
1561 {
1562 	u8 *buf;
1563 	unsigned int buflen;
1564 
1565 	if (cmd->use_sg) {
1566 		struct scatterlist *sg;
1567 
1568 		sg = (struct scatterlist *) cmd->request_buffer;
1569 		buf = kmap_atomic(sg->page, KM_IRQ0) + sg->offset;
1570 		buflen = sg->length;
1571 	} else {
1572 		buf = cmd->request_buffer;
1573 		buflen = cmd->request_bufflen;
1574 	}
1575 
1576 	*buf_out = buf;
1577 	return buflen;
1578 }
1579 
1580 /**
1581  *	ata_scsi_rbuf_put - Unmap response buffer.
1582  *	@cmd: SCSI command containing buffer to be unmapped.
1583  *	@buf: buffer to unmap
1584  *
1585  *	Unmaps response buffer contained within @cmd.
1586  *
1587  *	LOCKING:
1588  *	spin_lock_irqsave(host lock)
1589  */
1590 
1591 static inline void ata_scsi_rbuf_put(struct scsi_cmnd *cmd, u8 *buf)
1592 {
1593 	if (cmd->use_sg) {
1594 		struct scatterlist *sg;
1595 
1596 		sg = (struct scatterlist *) cmd->request_buffer;
1597 		kunmap_atomic(buf - sg->offset, KM_IRQ0);
1598 	}
1599 }
1600 
1601 /**
1602  *	ata_scsi_rbuf_fill - wrapper for SCSI command simulators
1603  *	@args: device IDENTIFY data / SCSI command of interest.
1604  *	@actor: Callback hook for desired SCSI command simulator
1605  *
1606  *	Takes care of the hard work of simulating a SCSI command...
1607  *	Mapping the response buffer, calling the command's handler,
1608  *	and handling the handler's return value.  This return value
1609  *	indicates whether the handler wishes the SCSI command to be
1610  *	completed successfully (0), or not (in which case cmd->result
1611  *	and sense buffer are assumed to be set).
1612  *
1613  *	LOCKING:
1614  *	spin_lock_irqsave(host lock)
1615  */
1616 
1617 void ata_scsi_rbuf_fill(struct ata_scsi_args *args,
1618 		        unsigned int (*actor) (struct ata_scsi_args *args,
1619 			     		   u8 *rbuf, unsigned int buflen))
1620 {
1621 	u8 *rbuf;
1622 	unsigned int buflen, rc;
1623 	struct scsi_cmnd *cmd = args->cmd;
1624 
1625 	buflen = ata_scsi_rbuf_get(cmd, &rbuf);
1626 	memset(rbuf, 0, buflen);
1627 	rc = actor(args, rbuf, buflen);
1628 	ata_scsi_rbuf_put(cmd, rbuf);
1629 
1630 	if (rc == 0)
1631 		cmd->result = SAM_STAT_GOOD;
1632 	args->done(cmd);
1633 }
1634 
1635 /**
1636  *	ATA_SCSI_RBUF_SET - helper to set values in SCSI response buffer
1637  *	@idx: byte index into SCSI response buffer
1638  *	@val: value to set
1639  *
1640  *	To be used by SCSI command simulator functions.  This macros
1641  *	expects two local variables, u8 *rbuf and unsigned int buflen,
1642  *	are in scope.
1643  *
1644  *	LOCKING:
1645  *	None.
1646  */
1647 #define ATA_SCSI_RBUF_SET(idx, val) do { \
1648 		if ((idx) < buflen) rbuf[(idx)] = (u8)(val); \
1649 	} while (0)
1650 
1651 /**
1652  *	ata_scsiop_inq_std - Simulate INQUIRY command
1653  *	@args: device IDENTIFY data / SCSI command of interest.
1654  *	@rbuf: Response buffer, to which simulated SCSI cmd output is sent.
1655  *	@buflen: Response buffer length.
1656  *
1657  *	Returns standard device identification data associated
1658  *	with non-VPD INQUIRY command output.
1659  *
1660  *	LOCKING:
1661  *	spin_lock_irqsave(host lock)
1662  */
1663 
1664 unsigned int ata_scsiop_inq_std(struct ata_scsi_args *args, u8 *rbuf,
1665 			       unsigned int buflen)
1666 {
1667 	u8 hdr[] = {
1668 		TYPE_DISK,
1669 		0,
1670 		0x5,	/* claim SPC-3 version compatibility */
1671 		2,
1672 		95 - 4
1673 	};
1674 
1675 	/* set scsi removeable (RMB) bit per ata bit */
1676 	if (ata_id_removeable(args->id))
1677 		hdr[1] |= (1 << 7);
1678 
1679 	VPRINTK("ENTER\n");
1680 
1681 	memcpy(rbuf, hdr, sizeof(hdr));
1682 
1683 	if (buflen > 35) {
1684 		memcpy(&rbuf[8], "ATA     ", 8);
1685 		ata_id_string(args->id, &rbuf[16], ATA_ID_PROD, 16);
1686 		ata_id_string(args->id, &rbuf[32], ATA_ID_FW_REV, 4);
1687 		if (rbuf[32] == 0 || rbuf[32] == ' ')
1688 			memcpy(&rbuf[32], "n/a ", 4);
1689 	}
1690 
1691 	if (buflen > 63) {
1692 		const u8 versions[] = {
1693 			0x60,	/* SAM-3 (no version claimed) */
1694 
1695 			0x03,
1696 			0x20,	/* SBC-2 (no version claimed) */
1697 
1698 			0x02,
1699 			0x60	/* SPC-3 (no version claimed) */
1700 		};
1701 
1702 		memcpy(rbuf + 59, versions, sizeof(versions));
1703 	}
1704 
1705 	return 0;
1706 }
1707 
1708 /**
1709  *	ata_scsiop_inq_00 - Simulate INQUIRY VPD page 0, list of pages
1710  *	@args: device IDENTIFY data / SCSI command of interest.
1711  *	@rbuf: Response buffer, to which simulated SCSI cmd output is sent.
1712  *	@buflen: Response buffer length.
1713  *
1714  *	Returns list of inquiry VPD pages available.
1715  *
1716  *	LOCKING:
1717  *	spin_lock_irqsave(host lock)
1718  */
1719 
1720 unsigned int ata_scsiop_inq_00(struct ata_scsi_args *args, u8 *rbuf,
1721 			      unsigned int buflen)
1722 {
1723 	const u8 pages[] = {
1724 		0x00,	/* page 0x00, this page */
1725 		0x80,	/* page 0x80, unit serial no page */
1726 		0x83	/* page 0x83, device ident page */
1727 	};
1728 	rbuf[3] = sizeof(pages);	/* number of supported VPD pages */
1729 
1730 	if (buflen > 6)
1731 		memcpy(rbuf + 4, pages, sizeof(pages));
1732 
1733 	return 0;
1734 }
1735 
1736 /**
1737  *	ata_scsiop_inq_80 - Simulate INQUIRY VPD page 80, device serial number
1738  *	@args: device IDENTIFY data / SCSI command of interest.
1739  *	@rbuf: Response buffer, to which simulated SCSI cmd output is sent.
1740  *	@buflen: Response buffer length.
1741  *
1742  *	Returns ATA device serial number.
1743  *
1744  *	LOCKING:
1745  *	spin_lock_irqsave(host lock)
1746  */
1747 
1748 unsigned int ata_scsiop_inq_80(struct ata_scsi_args *args, u8 *rbuf,
1749 			      unsigned int buflen)
1750 {
1751 	const u8 hdr[] = {
1752 		0,
1753 		0x80,			/* this page code */
1754 		0,
1755 		ATA_ID_SERNO_LEN,	/* page len */
1756 	};
1757 	memcpy(rbuf, hdr, sizeof(hdr));
1758 
1759 	if (buflen > (ATA_ID_SERNO_LEN + 4 - 1))
1760 		ata_id_string(args->id, (unsigned char *) &rbuf[4],
1761 			      ATA_ID_SERNO, ATA_ID_SERNO_LEN);
1762 
1763 	return 0;
1764 }
1765 
1766 /**
1767  *	ata_scsiop_inq_83 - Simulate INQUIRY VPD page 83, device identity
1768  *	@args: device IDENTIFY data / SCSI command of interest.
1769  *	@rbuf: Response buffer, to which simulated SCSI cmd output is sent.
1770  *	@buflen: Response buffer length.
1771  *
1772  *	Yields two logical unit device identification designators:
1773  *	 - vendor specific ASCII containing the ATA serial number
1774  *	 - SAT defined "t10 vendor id based" containing ASCII vendor
1775  *	   name ("ATA     "), model and serial numbers.
1776  *
1777  *	LOCKING:
1778  *	spin_lock_irqsave(host lock)
1779  */
1780 
1781 unsigned int ata_scsiop_inq_83(struct ata_scsi_args *args, u8 *rbuf,
1782 			      unsigned int buflen)
1783 {
1784 	int num;
1785 	const int sat_model_serial_desc_len = 68;
1786 
1787 	rbuf[1] = 0x83;			/* this page code */
1788 	num = 4;
1789 
1790 	if (buflen > (ATA_ID_SERNO_LEN + num + 3)) {
1791 		/* piv=0, assoc=lu, code_set=ACSII, designator=vendor */
1792 		rbuf[num + 0] = 2;
1793 		rbuf[num + 3] = ATA_ID_SERNO_LEN;
1794 		num += 4;
1795 		ata_id_string(args->id, (unsigned char *) rbuf + num,
1796 			      ATA_ID_SERNO, ATA_ID_SERNO_LEN);
1797 		num += ATA_ID_SERNO_LEN;
1798 	}
1799 	if (buflen > (sat_model_serial_desc_len + num + 3)) {
1800 		/* SAT defined lu model and serial numbers descriptor */
1801 		/* piv=0, assoc=lu, code_set=ACSII, designator=t10 vendor id */
1802 		rbuf[num + 0] = 2;
1803 		rbuf[num + 1] = 1;
1804 		rbuf[num + 3] = sat_model_serial_desc_len;
1805 		num += 4;
1806 		memcpy(rbuf + num, "ATA     ", 8);
1807 		num += 8;
1808 		ata_id_string(args->id, (unsigned char *) rbuf + num,
1809 			      ATA_ID_PROD, ATA_ID_PROD_LEN);
1810 		num += ATA_ID_PROD_LEN;
1811 		ata_id_string(args->id, (unsigned char *) rbuf + num,
1812 			      ATA_ID_SERNO, ATA_ID_SERNO_LEN);
1813 		num += ATA_ID_SERNO_LEN;
1814 	}
1815 	rbuf[3] = num - 4;    /* page len (assume less than 256 bytes) */
1816 	return 0;
1817 }
1818 
1819 /**
1820  *	ata_scsiop_noop - Command handler that simply returns success.
1821  *	@args: device IDENTIFY data / SCSI command of interest.
1822  *	@rbuf: Response buffer, to which simulated SCSI cmd output is sent.
1823  *	@buflen: Response buffer length.
1824  *
1825  *	No operation.  Simply returns success to caller, to indicate
1826  *	that the caller should successfully complete this SCSI command.
1827  *
1828  *	LOCKING:
1829  *	spin_lock_irqsave(host lock)
1830  */
1831 
1832 unsigned int ata_scsiop_noop(struct ata_scsi_args *args, u8 *rbuf,
1833 			    unsigned int buflen)
1834 {
1835 	VPRINTK("ENTER\n");
1836 	return 0;
1837 }
1838 
1839 /**
1840  *	ata_msense_push - Push data onto MODE SENSE data output buffer
1841  *	@ptr_io: (input/output) Location to store more output data
1842  *	@last: End of output data buffer
1843  *	@buf: Pointer to BLOB being added to output buffer
1844  *	@buflen: Length of BLOB
1845  *
1846  *	Store MODE SENSE data on an output buffer.
1847  *
1848  *	LOCKING:
1849  *	None.
1850  */
1851 
1852 static void ata_msense_push(u8 **ptr_io, const u8 *last,
1853 			    const u8 *buf, unsigned int buflen)
1854 {
1855 	u8 *ptr = *ptr_io;
1856 
1857 	if ((ptr + buflen - 1) > last)
1858 		return;
1859 
1860 	memcpy(ptr, buf, buflen);
1861 
1862 	ptr += buflen;
1863 
1864 	*ptr_io = ptr;
1865 }
1866 
1867 /**
1868  *	ata_msense_caching - Simulate MODE SENSE caching info page
1869  *	@id: device IDENTIFY data
1870  *	@ptr_io: (input/output) Location to store more output data
1871  *	@last: End of output data buffer
1872  *
1873  *	Generate a caching info page, which conditionally indicates
1874  *	write caching to the SCSI layer, depending on device
1875  *	capabilities.
1876  *
1877  *	LOCKING:
1878  *	None.
1879  */
1880 
1881 static unsigned int ata_msense_caching(u16 *id, u8 **ptr_io,
1882 				       const u8 *last)
1883 {
1884 	u8 page[CACHE_MPAGE_LEN];
1885 
1886 	memcpy(page, def_cache_mpage, sizeof(page));
1887 	if (ata_id_wcache_enabled(id))
1888 		page[2] |= (1 << 2);	/* write cache enable */
1889 	if (!ata_id_rahead_enabled(id))
1890 		page[12] |= (1 << 5);	/* disable read ahead */
1891 
1892 	ata_msense_push(ptr_io, last, page, sizeof(page));
1893 	return sizeof(page);
1894 }
1895 
1896 /**
1897  *	ata_msense_ctl_mode - Simulate MODE SENSE control mode page
1898  *	@dev: Device associated with this MODE SENSE command
1899  *	@ptr_io: (input/output) Location to store more output data
1900  *	@last: End of output data buffer
1901  *
1902  *	Generate a generic MODE SENSE control mode page.
1903  *
1904  *	LOCKING:
1905  *	None.
1906  */
1907 
1908 static unsigned int ata_msense_ctl_mode(u8 **ptr_io, const u8 *last)
1909 {
1910 	ata_msense_push(ptr_io, last, def_control_mpage,
1911 			sizeof(def_control_mpage));
1912 	return sizeof(def_control_mpage);
1913 }
1914 
1915 /**
1916  *	ata_msense_rw_recovery - Simulate MODE SENSE r/w error recovery page
1917  *	@dev: Device associated with this MODE SENSE command
1918  *	@ptr_io: (input/output) Location to store more output data
1919  *	@last: End of output data buffer
1920  *
1921  *	Generate a generic MODE SENSE r/w error recovery page.
1922  *
1923  *	LOCKING:
1924  *	None.
1925  */
1926 
1927 static unsigned int ata_msense_rw_recovery(u8 **ptr_io, const u8 *last)
1928 {
1929 
1930 	ata_msense_push(ptr_io, last, def_rw_recovery_mpage,
1931 			sizeof(def_rw_recovery_mpage));
1932 	return sizeof(def_rw_recovery_mpage);
1933 }
1934 
1935 /*
1936  * We can turn this into a real blacklist if it's needed, for now just
1937  * blacklist any Maxtor BANC1G10 revision firmware
1938  */
1939 static int ata_dev_supports_fua(u16 *id)
1940 {
1941 	unsigned char model[ATA_ID_PROD_LEN + 1], fw[ATA_ID_FW_REV_LEN + 1];
1942 
1943 	if (!libata_fua)
1944 		return 0;
1945 	if (!ata_id_has_fua(id))
1946 		return 0;
1947 
1948 	ata_id_c_string(id, model, ATA_ID_PROD, sizeof(model));
1949 	ata_id_c_string(id, fw, ATA_ID_FW_REV, sizeof(fw));
1950 
1951 	if (strcmp(model, "Maxtor"))
1952 		return 1;
1953 	if (strcmp(fw, "BANC1G10"))
1954 		return 1;
1955 
1956 	return 0; /* blacklisted */
1957 }
1958 
1959 /**
1960  *	ata_scsiop_mode_sense - Simulate MODE SENSE 6, 10 commands
1961  *	@args: device IDENTIFY data / SCSI command of interest.
1962  *	@rbuf: Response buffer, to which simulated SCSI cmd output is sent.
1963  *	@buflen: Response buffer length.
1964  *
1965  *	Simulate MODE SENSE commands. Assume this is invoked for direct
1966  *	access devices (e.g. disks) only. There should be no block
1967  *	descriptor for other device types.
1968  *
1969  *	LOCKING:
1970  *	spin_lock_irqsave(host lock)
1971  */
1972 
1973 unsigned int ata_scsiop_mode_sense(struct ata_scsi_args *args, u8 *rbuf,
1974 				  unsigned int buflen)
1975 {
1976 	struct ata_device *dev = args->dev;
1977 	u8 *scsicmd = args->cmd->cmnd, *p, *last;
1978 	const u8 sat_blk_desc[] = {
1979 		0, 0, 0, 0,	/* number of blocks: sat unspecified */
1980 		0,
1981 		0, 0x2, 0x0	/* block length: 512 bytes */
1982 	};
1983 	u8 pg, spg;
1984 	unsigned int ebd, page_control, six_byte, output_len, alloc_len, minlen;
1985 	u8 dpofua;
1986 
1987 	VPRINTK("ENTER\n");
1988 
1989 	six_byte = (scsicmd[0] == MODE_SENSE);
1990 	ebd = !(scsicmd[1] & 0x8);      /* dbd bit inverted == edb */
1991 	/*
1992 	 * LLBA bit in msense(10) ignored (compliant)
1993 	 */
1994 
1995 	page_control = scsicmd[2] >> 6;
1996 	switch (page_control) {
1997 	case 0: /* current */
1998 		break;  /* supported */
1999 	case 3: /* saved */
2000 		goto saving_not_supp;
2001 	case 1: /* changeable */
2002 	case 2: /* defaults */
2003 	default:
2004 		goto invalid_fld;
2005 	}
2006 
2007 	if (six_byte) {
2008 		output_len = 4 + (ebd ? 8 : 0);
2009 		alloc_len = scsicmd[4];
2010 	} else {
2011 		output_len = 8 + (ebd ? 8 : 0);
2012 		alloc_len = (scsicmd[7] << 8) + scsicmd[8];
2013 	}
2014 	minlen = (alloc_len < buflen) ? alloc_len : buflen;
2015 
2016 	p = rbuf + output_len;
2017 	last = rbuf + minlen - 1;
2018 
2019 	pg = scsicmd[2] & 0x3f;
2020 	spg = scsicmd[3];
2021 	/*
2022 	 * No mode subpages supported (yet) but asking for _all_
2023 	 * subpages may be valid
2024 	 */
2025 	if (spg && (spg != ALL_SUB_MPAGES))
2026 		goto invalid_fld;
2027 
2028 	switch(pg) {
2029 	case RW_RECOVERY_MPAGE:
2030 		output_len += ata_msense_rw_recovery(&p, last);
2031 		break;
2032 
2033 	case CACHE_MPAGE:
2034 		output_len += ata_msense_caching(args->id, &p, last);
2035 		break;
2036 
2037 	case CONTROL_MPAGE: {
2038 		output_len += ata_msense_ctl_mode(&p, last);
2039 		break;
2040 		}
2041 
2042 	case ALL_MPAGES:
2043 		output_len += ata_msense_rw_recovery(&p, last);
2044 		output_len += ata_msense_caching(args->id, &p, last);
2045 		output_len += ata_msense_ctl_mode(&p, last);
2046 		break;
2047 
2048 	default:		/* invalid page code */
2049 		goto invalid_fld;
2050 	}
2051 
2052 	if (minlen < 1)
2053 		return 0;
2054 
2055 	dpofua = 0;
2056 	if (ata_dev_supports_fua(args->id) && (dev->flags & ATA_DFLAG_LBA48) &&
2057 	    (!(dev->flags & ATA_DFLAG_PIO) || dev->multi_count))
2058 		dpofua = 1 << 4;
2059 
2060 	if (six_byte) {
2061 		output_len--;
2062 		rbuf[0] = output_len;
2063 		if (minlen > 2)
2064 			rbuf[2] |= dpofua;
2065 		if (ebd) {
2066 			if (minlen > 3)
2067 				rbuf[3] = sizeof(sat_blk_desc);
2068 			if (minlen > 11)
2069 				memcpy(rbuf + 4, sat_blk_desc,
2070 				       sizeof(sat_blk_desc));
2071 		}
2072 	} else {
2073 		output_len -= 2;
2074 		rbuf[0] = output_len >> 8;
2075 		if (minlen > 1)
2076 			rbuf[1] = output_len;
2077 		if (minlen > 3)
2078 			rbuf[3] |= dpofua;
2079 		if (ebd) {
2080 			if (minlen > 7)
2081 				rbuf[7] = sizeof(sat_blk_desc);
2082 			if (minlen > 15)
2083 				memcpy(rbuf + 8, sat_blk_desc,
2084 				       sizeof(sat_blk_desc));
2085 		}
2086 	}
2087 	return 0;
2088 
2089 invalid_fld:
2090 	ata_scsi_set_sense(args->cmd, ILLEGAL_REQUEST, 0x24, 0x0);
2091 	/* "Invalid field in cbd" */
2092 	return 1;
2093 
2094 saving_not_supp:
2095 	ata_scsi_set_sense(args->cmd, ILLEGAL_REQUEST, 0x39, 0x0);
2096 	 /* "Saving parameters not supported" */
2097 	return 1;
2098 }
2099 
2100 /**
2101  *	ata_scsiop_read_cap - Simulate READ CAPACITY[ 16] commands
2102  *	@args: device IDENTIFY data / SCSI command of interest.
2103  *	@rbuf: Response buffer, to which simulated SCSI cmd output is sent.
2104  *	@buflen: Response buffer length.
2105  *
2106  *	Simulate READ CAPACITY commands.
2107  *
2108  *	LOCKING:
2109  *	None.
2110  */
2111 unsigned int ata_scsiop_read_cap(struct ata_scsi_args *args, u8 *rbuf,
2112 			        unsigned int buflen)
2113 {
2114 	u64 last_lba = args->dev->n_sectors - 1; /* LBA of the last block */
2115 
2116 	VPRINTK("ENTER\n");
2117 
2118 	if (args->cmd->cmnd[0] == READ_CAPACITY) {
2119 		if (last_lba >= 0xffffffffULL)
2120 			last_lba = 0xffffffff;
2121 
2122 		/* sector count, 32-bit */
2123 		ATA_SCSI_RBUF_SET(0, last_lba >> (8 * 3));
2124 		ATA_SCSI_RBUF_SET(1, last_lba >> (8 * 2));
2125 		ATA_SCSI_RBUF_SET(2, last_lba >> (8 * 1));
2126 		ATA_SCSI_RBUF_SET(3, last_lba);
2127 
2128 		/* sector size */
2129 		ATA_SCSI_RBUF_SET(6, ATA_SECT_SIZE >> 8);
2130 		ATA_SCSI_RBUF_SET(7, ATA_SECT_SIZE);
2131 	} else {
2132 		/* sector count, 64-bit */
2133 		ATA_SCSI_RBUF_SET(0, last_lba >> (8 * 7));
2134 		ATA_SCSI_RBUF_SET(1, last_lba >> (8 * 6));
2135 		ATA_SCSI_RBUF_SET(2, last_lba >> (8 * 5));
2136 		ATA_SCSI_RBUF_SET(3, last_lba >> (8 * 4));
2137 		ATA_SCSI_RBUF_SET(4, last_lba >> (8 * 3));
2138 		ATA_SCSI_RBUF_SET(5, last_lba >> (8 * 2));
2139 		ATA_SCSI_RBUF_SET(6, last_lba >> (8 * 1));
2140 		ATA_SCSI_RBUF_SET(7, last_lba);
2141 
2142 		/* sector size */
2143 		ATA_SCSI_RBUF_SET(10, ATA_SECT_SIZE >> 8);
2144 		ATA_SCSI_RBUF_SET(11, ATA_SECT_SIZE);
2145 	}
2146 
2147 	return 0;
2148 }
2149 
2150 /**
2151  *	ata_scsiop_report_luns - Simulate REPORT LUNS command
2152  *	@args: device IDENTIFY data / SCSI command of interest.
2153  *	@rbuf: Response buffer, to which simulated SCSI cmd output is sent.
2154  *	@buflen: Response buffer length.
2155  *
2156  *	Simulate REPORT LUNS command.
2157  *
2158  *	LOCKING:
2159  *	spin_lock_irqsave(host lock)
2160  */
2161 
2162 unsigned int ata_scsiop_report_luns(struct ata_scsi_args *args, u8 *rbuf,
2163 				   unsigned int buflen)
2164 {
2165 	VPRINTK("ENTER\n");
2166 	rbuf[3] = 8;	/* just one lun, LUN 0, size 8 bytes */
2167 
2168 	return 0;
2169 }
2170 
2171 /**
2172  *	ata_scsi_set_sense - Set SCSI sense data and status
2173  *	@cmd: SCSI request to be handled
2174  *	@sk: SCSI-defined sense key
2175  *	@asc: SCSI-defined additional sense code
2176  *	@ascq: SCSI-defined additional sense code qualifier
2177  *
2178  *	Helper function that builds a valid fixed format, current
2179  *	response code and the given sense key (sk), additional sense
2180  *	code (asc) and additional sense code qualifier (ascq) with
2181  *	a SCSI command status of %SAM_STAT_CHECK_CONDITION and
2182  *	DRIVER_SENSE set in the upper bits of scsi_cmnd::result .
2183  *
2184  *	LOCKING:
2185  *	Not required
2186  */
2187 
2188 void ata_scsi_set_sense(struct scsi_cmnd *cmd, u8 sk, u8 asc, u8 ascq)
2189 {
2190 	cmd->result = (DRIVER_SENSE << 24) | SAM_STAT_CHECK_CONDITION;
2191 
2192 	cmd->sense_buffer[0] = 0x70;	/* fixed format, current */
2193 	cmd->sense_buffer[2] = sk;
2194 	cmd->sense_buffer[7] = 18 - 8;	/* additional sense length */
2195 	cmd->sense_buffer[12] = asc;
2196 	cmd->sense_buffer[13] = ascq;
2197 }
2198 
2199 /**
2200  *	ata_scsi_badcmd - End a SCSI request with an error
2201  *	@cmd: SCSI request to be handled
2202  *	@done: SCSI command completion function
2203  *	@asc: SCSI-defined additional sense code
2204  *	@ascq: SCSI-defined additional sense code qualifier
2205  *
2206  *	Helper function that completes a SCSI command with
2207  *	%SAM_STAT_CHECK_CONDITION, with a sense key %ILLEGAL_REQUEST
2208  *	and the specified additional sense codes.
2209  *
2210  *	LOCKING:
2211  *	spin_lock_irqsave(host lock)
2212  */
2213 
2214 void ata_scsi_badcmd(struct scsi_cmnd *cmd, void (*done)(struct scsi_cmnd *), u8 asc, u8 ascq)
2215 {
2216 	DPRINTK("ENTER\n");
2217 	ata_scsi_set_sense(cmd, ILLEGAL_REQUEST, asc, ascq);
2218 
2219 	done(cmd);
2220 }
2221 
2222 static void atapi_sense_complete(struct ata_queued_cmd *qc)
2223 {
2224 	if (qc->err_mask && ((qc->err_mask & AC_ERR_DEV) == 0)) {
2225 		/* FIXME: not quite right; we don't want the
2226 		 * translation of taskfile registers into
2227 		 * a sense descriptors, since that's only
2228 		 * correct for ATA, not ATAPI
2229 		 */
2230 		ata_gen_passthru_sense(qc);
2231 	}
2232 
2233 	qc->scsidone(qc->scsicmd);
2234 	ata_qc_free(qc);
2235 }
2236 
2237 /* is it pointless to prefer PIO for "safety reasons"? */
2238 static inline int ata_pio_use_silly(struct ata_port *ap)
2239 {
2240 	return (ap->flags & ATA_FLAG_PIO_DMA);
2241 }
2242 
2243 static void atapi_request_sense(struct ata_queued_cmd *qc)
2244 {
2245 	struct ata_port *ap = qc->ap;
2246 	struct scsi_cmnd *cmd = qc->scsicmd;
2247 
2248 	DPRINTK("ATAPI request sense\n");
2249 
2250 	/* FIXME: is this needed? */
2251 	memset(cmd->sense_buffer, 0, sizeof(cmd->sense_buffer));
2252 
2253 	ap->ops->tf_read(ap, &qc->tf);
2254 
2255 	/* fill these in, for the case where they are -not- overwritten */
2256 	cmd->sense_buffer[0] = 0x70;
2257 	cmd->sense_buffer[2] = qc->tf.feature >> 4;
2258 
2259 	ata_qc_reinit(qc);
2260 
2261 	ata_sg_init_one(qc, cmd->sense_buffer, sizeof(cmd->sense_buffer));
2262 	qc->dma_dir = DMA_FROM_DEVICE;
2263 
2264 	memset(&qc->cdb, 0, qc->dev->cdb_len);
2265 	qc->cdb[0] = REQUEST_SENSE;
2266 	qc->cdb[4] = SCSI_SENSE_BUFFERSIZE;
2267 
2268 	qc->tf.flags |= ATA_TFLAG_ISADDR | ATA_TFLAG_DEVICE;
2269 	qc->tf.command = ATA_CMD_PACKET;
2270 
2271 	if (ata_pio_use_silly(ap)) {
2272 		qc->tf.protocol = ATA_PROT_ATAPI_DMA;
2273 		qc->tf.feature |= ATAPI_PKT_DMA;
2274 	} else {
2275 		qc->tf.protocol = ATA_PROT_ATAPI;
2276 		qc->tf.lbam = (8 * 1024) & 0xff;
2277 		qc->tf.lbah = (8 * 1024) >> 8;
2278 	}
2279 	qc->nbytes = SCSI_SENSE_BUFFERSIZE;
2280 
2281 	qc->complete_fn = atapi_sense_complete;
2282 
2283 	ata_qc_issue(qc);
2284 
2285 	DPRINTK("EXIT\n");
2286 }
2287 
2288 static void atapi_qc_complete(struct ata_queued_cmd *qc)
2289 {
2290 	struct scsi_cmnd *cmd = qc->scsicmd;
2291 	unsigned int err_mask = qc->err_mask;
2292 
2293 	VPRINTK("ENTER, err_mask 0x%X\n", err_mask);
2294 
2295 	/* handle completion from new EH */
2296 	if (unlikely(qc->ap->ops->error_handler &&
2297 		     (err_mask || qc->flags & ATA_QCFLAG_SENSE_VALID))) {
2298 
2299 		if (!(qc->flags & ATA_QCFLAG_SENSE_VALID)) {
2300 			/* FIXME: not quite right; we don't want the
2301 			 * translation of taskfile registers into a
2302 			 * sense descriptors, since that's only
2303 			 * correct for ATA, not ATAPI
2304 			 */
2305 			ata_gen_passthru_sense(qc);
2306 		}
2307 
2308 		/* SCSI EH automatically locks door if sdev->locked is
2309 		 * set.  Sometimes door lock request continues to
2310 		 * fail, for example, when no media is present.  This
2311 		 * creates a loop - SCSI EH issues door lock which
2312 		 * fails and gets invoked again to acquire sense data
2313 		 * for the failed command.
2314 		 *
2315 		 * If door lock fails, always clear sdev->locked to
2316 		 * avoid this infinite loop.
2317 		 */
2318 		if (qc->cdb[0] == ALLOW_MEDIUM_REMOVAL)
2319 			qc->dev->sdev->locked = 0;
2320 
2321 		qc->scsicmd->result = SAM_STAT_CHECK_CONDITION;
2322 		qc->scsidone(cmd);
2323 		ata_qc_free(qc);
2324 		return;
2325 	}
2326 
2327 	/* successful completion or old EH failure path */
2328 	if (unlikely(err_mask & AC_ERR_DEV)) {
2329 		cmd->result = SAM_STAT_CHECK_CONDITION;
2330 		atapi_request_sense(qc);
2331 		return;
2332 	} else if (unlikely(err_mask)) {
2333 		/* FIXME: not quite right; we don't want the
2334 		 * translation of taskfile registers into
2335 		 * a sense descriptors, since that's only
2336 		 * correct for ATA, not ATAPI
2337 		 */
2338 		ata_gen_passthru_sense(qc);
2339 	} else {
2340 		u8 *scsicmd = cmd->cmnd;
2341 
2342 		if ((scsicmd[0] == INQUIRY) && ((scsicmd[1] & 0x03) == 0)) {
2343 			u8 *buf = NULL;
2344 			unsigned int buflen;
2345 
2346 			buflen = ata_scsi_rbuf_get(cmd, &buf);
2347 
2348 	/* ATAPI devices typically report zero for their SCSI version,
2349 	 * and sometimes deviate from the spec WRT response data
2350 	 * format.  If SCSI version is reported as zero like normal,
2351 	 * then we make the following fixups:  1) Fake MMC-5 version,
2352 	 * to indicate to the Linux scsi midlayer this is a modern
2353 	 * device.  2) Ensure response data format / ATAPI information
2354 	 * are always correct.
2355 	 */
2356 			if (buf[2] == 0) {
2357 				buf[2] = 0x5;
2358 				buf[3] = 0x32;
2359 			}
2360 
2361 			ata_scsi_rbuf_put(cmd, buf);
2362 		}
2363 
2364 		cmd->result = SAM_STAT_GOOD;
2365 	}
2366 
2367 	qc->scsidone(cmd);
2368 	ata_qc_free(qc);
2369 }
2370 /**
2371  *	atapi_xlat - Initialize PACKET taskfile
2372  *	@qc: command structure to be initialized
2373  *
2374  *	LOCKING:
2375  *	spin_lock_irqsave(host lock)
2376  *
2377  *	RETURNS:
2378  *	Zero on success, non-zero on failure.
2379  */
2380 static unsigned int atapi_xlat(struct ata_queued_cmd *qc)
2381 {
2382 	struct scsi_cmnd *scmd = qc->scsicmd;
2383 	struct ata_device *dev = qc->dev;
2384 	int using_pio = (dev->flags & ATA_DFLAG_PIO);
2385 	int nodata = (scmd->sc_data_direction == DMA_NONE);
2386 
2387 	memset(qc->cdb, 0, dev->cdb_len);
2388 	memcpy(qc->cdb, scmd->cmnd, scmd->cmd_len);
2389 
2390 	qc->complete_fn = atapi_qc_complete;
2391 
2392 	qc->tf.flags |= ATA_TFLAG_ISADDR | ATA_TFLAG_DEVICE;
2393 	if (scmd->sc_data_direction == DMA_TO_DEVICE) {
2394 		qc->tf.flags |= ATA_TFLAG_WRITE;
2395 		DPRINTK("direction: write\n");
2396 	}
2397 
2398 	qc->tf.command = ATA_CMD_PACKET;
2399 	qc->nbytes = scmd->request_bufflen;
2400 
2401 	/* check whether ATAPI DMA is safe */
2402 	if (!using_pio && ata_check_atapi_dma(qc))
2403 		using_pio = 1;
2404 
2405 	if (using_pio || nodata) {
2406 		/* no data, or PIO data xfer */
2407 		if (nodata)
2408 			qc->tf.protocol = ATA_PROT_ATAPI_NODATA;
2409 		else
2410 			qc->tf.protocol = ATA_PROT_ATAPI;
2411 		qc->tf.lbam = (8 * 1024) & 0xff;
2412 		qc->tf.lbah = (8 * 1024) >> 8;
2413 	} else {
2414 		/* DMA data xfer */
2415 		qc->tf.protocol = ATA_PROT_ATAPI_DMA;
2416 		qc->tf.feature |= ATAPI_PKT_DMA;
2417 
2418 		if (atapi_dmadir && (scmd->sc_data_direction != DMA_TO_DEVICE))
2419 			/* some SATA bridges need us to indicate data xfer direction */
2420 			qc->tf.feature |= ATAPI_DMADIR;
2421 	}
2422 
2423 	return 0;
2424 }
2425 
2426 static struct ata_device * ata_find_dev(struct ata_port *ap, int id)
2427 {
2428 	if (likely(id < ATA_MAX_DEVICES))
2429 		return &ap->device[id];
2430 	return NULL;
2431 }
2432 
2433 static struct ata_device * __ata_scsi_find_dev(struct ata_port *ap,
2434 					const struct scsi_device *scsidev)
2435 {
2436 	/* skip commands not addressed to targets we simulate */
2437 	if (unlikely(scsidev->channel || scsidev->lun))
2438 		return NULL;
2439 
2440 	return ata_find_dev(ap, scsidev->id);
2441 }
2442 
2443 /**
2444  *	ata_scsi_dev_enabled - determine if device is enabled
2445  *	@dev: ATA device
2446  *
2447  *	Determine if commands should be sent to the specified device.
2448  *
2449  *	LOCKING:
2450  *	spin_lock_irqsave(host lock)
2451  *
2452  *	RETURNS:
2453  *	0 if commands are not allowed / 1 if commands are allowed
2454  */
2455 
2456 static int ata_scsi_dev_enabled(struct ata_device *dev)
2457 {
2458 	if (unlikely(!ata_dev_enabled(dev)))
2459 		return 0;
2460 
2461 	if (!atapi_enabled || (dev->ap->flags & ATA_FLAG_NO_ATAPI)) {
2462 		if (unlikely(dev->class == ATA_DEV_ATAPI)) {
2463 			ata_dev_printk(dev, KERN_WARNING,
2464 				       "WARNING: ATAPI is %s, device ignored.\n",
2465 				       atapi_enabled ? "not supported with this driver" : "disabled");
2466 			return 0;
2467 		}
2468 	}
2469 
2470 	return 1;
2471 }
2472 
2473 /**
2474  *	ata_scsi_find_dev - lookup ata_device from scsi_cmnd
2475  *	@ap: ATA port to which the device is attached
2476  *	@scsidev: SCSI device from which we derive the ATA device
2477  *
2478  *	Given various information provided in struct scsi_cmnd,
2479  *	map that onto an ATA bus, and using that mapping
2480  *	determine which ata_device is associated with the
2481  *	SCSI command to be sent.
2482  *
2483  *	LOCKING:
2484  *	spin_lock_irqsave(host lock)
2485  *
2486  *	RETURNS:
2487  *	Associated ATA device, or %NULL if not found.
2488  */
2489 static struct ata_device *
2490 ata_scsi_find_dev(struct ata_port *ap, const struct scsi_device *scsidev)
2491 {
2492 	struct ata_device *dev = __ata_scsi_find_dev(ap, scsidev);
2493 
2494 	if (unlikely(!dev || !ata_scsi_dev_enabled(dev)))
2495 		return NULL;
2496 
2497 	return dev;
2498 }
2499 
2500 /*
2501  *	ata_scsi_map_proto - Map pass-thru protocol value to taskfile value.
2502  *	@byte1: Byte 1 from pass-thru CDB.
2503  *
2504  *	RETURNS:
2505  *	ATA_PROT_UNKNOWN if mapping failed/unimplemented, protocol otherwise.
2506  */
2507 static u8
2508 ata_scsi_map_proto(u8 byte1)
2509 {
2510 	switch((byte1 & 0x1e) >> 1) {
2511 		case 3:		/* Non-data */
2512 			return ATA_PROT_NODATA;
2513 
2514 		case 6:		/* DMA */
2515 		case 10:	/* UDMA Data-in */
2516 		case 11:	/* UDMA Data-Out */
2517 			return ATA_PROT_DMA;
2518 
2519 		case 4:		/* PIO Data-in */
2520 		case 5:		/* PIO Data-out */
2521 			return ATA_PROT_PIO;
2522 
2523 		case 0:		/* Hard Reset */
2524 		case 1:		/* SRST */
2525 		case 8:		/* Device Diagnostic */
2526 		case 9:		/* Device Reset */
2527 		case 7:		/* DMA Queued */
2528 		case 12:	/* FPDMA */
2529 		case 15:	/* Return Response Info */
2530 		default:	/* Reserved */
2531 			break;
2532 	}
2533 
2534 	return ATA_PROT_UNKNOWN;
2535 }
2536 
2537 /**
2538  *	ata_scsi_pass_thru - convert ATA pass-thru CDB to taskfile
2539  *	@qc: command structure to be initialized
2540  *
2541  *	Handles either 12 or 16-byte versions of the CDB.
2542  *
2543  *	RETURNS:
2544  *	Zero on success, non-zero on failure.
2545  */
2546 static unsigned int ata_scsi_pass_thru(struct ata_queued_cmd *qc)
2547 {
2548 	struct ata_taskfile *tf = &(qc->tf);
2549 	struct scsi_cmnd *scmd = qc->scsicmd;
2550 	struct ata_device *dev = qc->dev;
2551 	const u8 *cdb = scmd->cmnd;
2552 
2553 	if ((tf->protocol = ata_scsi_map_proto(cdb[1])) == ATA_PROT_UNKNOWN)
2554 		goto invalid_fld;
2555 
2556 	/* We may not issue DMA commands if no DMA mode is set */
2557 	if (tf->protocol == ATA_PROT_DMA && dev->dma_mode == 0)
2558 		goto invalid_fld;
2559 
2560 	/*
2561 	 * 12 and 16 byte CDBs use different offsets to
2562 	 * provide the various register values.
2563 	 */
2564 	if (cdb[0] == ATA_16) {
2565 		/*
2566 		 * 16-byte CDB - may contain extended commands.
2567 		 *
2568 		 * If that is the case, copy the upper byte register values.
2569 		 */
2570 		if (cdb[1] & 0x01) {
2571 			tf->hob_feature = cdb[3];
2572 			tf->hob_nsect = cdb[5];
2573 			tf->hob_lbal = cdb[7];
2574 			tf->hob_lbam = cdb[9];
2575 			tf->hob_lbah = cdb[11];
2576 			tf->flags |= ATA_TFLAG_LBA48;
2577 		} else
2578 			tf->flags &= ~ATA_TFLAG_LBA48;
2579 
2580 		/*
2581 		 * Always copy low byte, device and command registers.
2582 		 */
2583 		tf->feature = cdb[4];
2584 		tf->nsect = cdb[6];
2585 		tf->lbal = cdb[8];
2586 		tf->lbam = cdb[10];
2587 		tf->lbah = cdb[12];
2588 		tf->device = cdb[13];
2589 		tf->command = cdb[14];
2590 	} else {
2591 		/*
2592 		 * 12-byte CDB - incapable of extended commands.
2593 		 */
2594 		tf->flags &= ~ATA_TFLAG_LBA48;
2595 
2596 		tf->feature = cdb[3];
2597 		tf->nsect = cdb[4];
2598 		tf->lbal = cdb[5];
2599 		tf->lbam = cdb[6];
2600 		tf->lbah = cdb[7];
2601 		tf->device = cdb[8];
2602 		tf->command = cdb[9];
2603 	}
2604 
2605 	/* enforce correct master/slave bit */
2606 	tf->device = dev->devno ?
2607 		tf->device | ATA_DEV1 : tf->device & ~ATA_DEV1;
2608 
2609 	/* sanity check for pio multi commands */
2610 	if ((cdb[1] & 0xe0) && !is_multi_taskfile(tf))
2611 		goto invalid_fld;
2612 
2613 	if (is_multi_taskfile(tf)) {
2614 		unsigned int multi_count = 1 << (cdb[1] >> 5);
2615 
2616 		/* compare the passed through multi_count
2617 		 * with the cached multi_count of libata
2618 		 */
2619 		if (multi_count != dev->multi_count)
2620 			ata_dev_printk(dev, KERN_WARNING,
2621 				       "invalid multi_count %u ignored\n",
2622 				       multi_count);
2623 	}
2624 
2625 	/* READ/WRITE LONG use a non-standard sect_size */
2626 	qc->sect_size = ATA_SECT_SIZE;
2627 	switch (tf->command) {
2628 	case ATA_CMD_READ_LONG:
2629 	case ATA_CMD_READ_LONG_ONCE:
2630 	case ATA_CMD_WRITE_LONG:
2631 	case ATA_CMD_WRITE_LONG_ONCE:
2632 		if (tf->protocol != ATA_PROT_PIO || tf->nsect != 1)
2633 			goto invalid_fld;
2634 		qc->sect_size = scmd->request_bufflen;
2635 	}
2636 
2637 	/*
2638 	 * Filter SET_FEATURES - XFER MODE command -- otherwise,
2639 	 * SET_FEATURES - XFER MODE must be preceded/succeeded
2640 	 * by an update to hardware-specific registers for each
2641 	 * controller (i.e. the reason for ->set_piomode(),
2642 	 * ->set_dmamode(), and ->post_set_mode() hooks).
2643 	 */
2644 	if ((tf->command == ATA_CMD_SET_FEATURES)
2645 	 && (tf->feature == SETFEATURES_XFER))
2646 		goto invalid_fld;
2647 
2648 	/*
2649 	 * Set flags so that all registers will be written,
2650 	 * and pass on write indication (used for PIO/DMA
2651 	 * setup.)
2652 	 */
2653 	tf->flags |= (ATA_TFLAG_ISADDR | ATA_TFLAG_DEVICE);
2654 
2655 	if (scmd->sc_data_direction == DMA_TO_DEVICE)
2656 		tf->flags |= ATA_TFLAG_WRITE;
2657 
2658 	/*
2659 	 * Set transfer length.
2660 	 *
2661 	 * TODO: find out if we need to do more here to
2662 	 *       cover scatter/gather case.
2663 	 */
2664 	qc->nbytes = scmd->request_bufflen;
2665 
2666 	/* request result TF */
2667 	qc->flags |= ATA_QCFLAG_RESULT_TF;
2668 
2669 	return 0;
2670 
2671  invalid_fld:
2672 	ata_scsi_set_sense(scmd, ILLEGAL_REQUEST, 0x24, 0x00);
2673 	/* "Invalid field in cdb" */
2674 	return 1;
2675 }
2676 
2677 /**
2678  *	ata_get_xlat_func - check if SCSI to ATA translation is possible
2679  *	@dev: ATA device
2680  *	@cmd: SCSI command opcode to consider
2681  *
2682  *	Look up the SCSI command given, and determine whether the
2683  *	SCSI command is to be translated or simulated.
2684  *
2685  *	RETURNS:
2686  *	Pointer to translation function if possible, %NULL if not.
2687  */
2688 
2689 static inline ata_xlat_func_t ata_get_xlat_func(struct ata_device *dev, u8 cmd)
2690 {
2691 	switch (cmd) {
2692 	case READ_6:
2693 	case READ_10:
2694 	case READ_16:
2695 
2696 	case WRITE_6:
2697 	case WRITE_10:
2698 	case WRITE_16:
2699 		return ata_scsi_rw_xlat;
2700 
2701 	case SYNCHRONIZE_CACHE:
2702 		if (ata_try_flush_cache(dev))
2703 			return ata_scsi_flush_xlat;
2704 		break;
2705 
2706 	case VERIFY:
2707 	case VERIFY_16:
2708 		return ata_scsi_verify_xlat;
2709 
2710 	case ATA_12:
2711 	case ATA_16:
2712 		return ata_scsi_pass_thru;
2713 
2714 	case START_STOP:
2715 		return ata_scsi_start_stop_xlat;
2716 	}
2717 
2718 	return NULL;
2719 }
2720 
2721 /**
2722  *	ata_scsi_dump_cdb - dump SCSI command contents to dmesg
2723  *	@ap: ATA port to which the command was being sent
2724  *	@cmd: SCSI command to dump
2725  *
2726  *	Prints the contents of a SCSI command via printk().
2727  */
2728 
2729 static inline void ata_scsi_dump_cdb(struct ata_port *ap,
2730 				     struct scsi_cmnd *cmd)
2731 {
2732 #ifdef ATA_DEBUG
2733 	struct scsi_device *scsidev = cmd->device;
2734 	u8 *scsicmd = cmd->cmnd;
2735 
2736 	DPRINTK("CDB (%u:%d,%d,%d) %02x %02x %02x %02x %02x %02x %02x %02x %02x\n",
2737 		ap->print_id,
2738 		scsidev->channel, scsidev->id, scsidev->lun,
2739 		scsicmd[0], scsicmd[1], scsicmd[2], scsicmd[3],
2740 		scsicmd[4], scsicmd[5], scsicmd[6], scsicmd[7],
2741 		scsicmd[8]);
2742 #endif
2743 }
2744 
2745 static inline int __ata_scsi_queuecmd(struct scsi_cmnd *scmd,
2746 				      void (*done)(struct scsi_cmnd *),
2747 				      struct ata_device *dev)
2748 {
2749 	int rc = 0;
2750 
2751 	if (unlikely(!scmd->cmd_len || scmd->cmd_len > dev->cdb_len)) {
2752 		DPRINTK("bad CDB len=%u, max=%u\n",
2753 			scmd->cmd_len, dev->cdb_len);
2754 		scmd->result = DID_ERROR << 16;
2755 		done(scmd);
2756 		return 0;
2757 	}
2758 
2759 	if (dev->class == ATA_DEV_ATA) {
2760 		ata_xlat_func_t xlat_func = ata_get_xlat_func(dev,
2761 							      scmd->cmnd[0]);
2762 
2763 		if (xlat_func)
2764 			rc = ata_scsi_translate(dev, scmd, done, xlat_func);
2765 		else
2766 			ata_scsi_simulate(dev, scmd, done);
2767 	} else
2768 		rc = ata_scsi_translate(dev, scmd, done, atapi_xlat);
2769 
2770 	return rc;
2771 }
2772 
2773 /**
2774  *	ata_scsi_queuecmd - Issue SCSI cdb to libata-managed device
2775  *	@cmd: SCSI command to be sent
2776  *	@done: Completion function, called when command is complete
2777  *
2778  *	In some cases, this function translates SCSI commands into
2779  *	ATA taskfiles, and queues the taskfiles to be sent to
2780  *	hardware.  In other cases, this function simulates a
2781  *	SCSI device by evaluating and responding to certain
2782  *	SCSI commands.  This creates the overall effect of
2783  *	ATA and ATAPI devices appearing as SCSI devices.
2784  *
2785  *	LOCKING:
2786  *	Releases scsi-layer-held lock, and obtains host lock.
2787  *
2788  *	RETURNS:
2789  *	Return value from __ata_scsi_queuecmd() if @cmd can be queued,
2790  *	0 otherwise.
2791  */
2792 int ata_scsi_queuecmd(struct scsi_cmnd *cmd, void (*done)(struct scsi_cmnd *))
2793 {
2794 	struct ata_port *ap;
2795 	struct ata_device *dev;
2796 	struct scsi_device *scsidev = cmd->device;
2797 	struct Scsi_Host *shost = scsidev->host;
2798 	int rc = 0;
2799 
2800 	ap = ata_shost_to_port(shost);
2801 
2802 	spin_unlock(shost->host_lock);
2803 	spin_lock(ap->lock);
2804 
2805 	ata_scsi_dump_cdb(ap, cmd);
2806 
2807 	dev = ata_scsi_find_dev(ap, scsidev);
2808 	if (likely(dev))
2809 		rc = __ata_scsi_queuecmd(cmd, done, dev);
2810 	else {
2811 		cmd->result = (DID_BAD_TARGET << 16);
2812 		done(cmd);
2813 	}
2814 
2815 	spin_unlock(ap->lock);
2816 	spin_lock(shost->host_lock);
2817 	return rc;
2818 }
2819 
2820 /**
2821  *	ata_scsi_simulate - simulate SCSI command on ATA device
2822  *	@dev: the target device
2823  *	@cmd: SCSI command being sent to device.
2824  *	@done: SCSI command completion function.
2825  *
2826  *	Interprets and directly executes a select list of SCSI commands
2827  *	that can be handled internally.
2828  *
2829  *	LOCKING:
2830  *	spin_lock_irqsave(host lock)
2831  */
2832 
2833 void ata_scsi_simulate(struct ata_device *dev, struct scsi_cmnd *cmd,
2834 		      void (*done)(struct scsi_cmnd *))
2835 {
2836 	struct ata_scsi_args args;
2837 	const u8 *scsicmd = cmd->cmnd;
2838 
2839 	args.dev = dev;
2840 	args.id = dev->id;
2841 	args.cmd = cmd;
2842 	args.done = done;
2843 
2844 	switch(scsicmd[0]) {
2845 		/* no-op's, complete with success */
2846 		case SYNCHRONIZE_CACHE:
2847 		case REZERO_UNIT:
2848 		case SEEK_6:
2849 		case SEEK_10:
2850 		case TEST_UNIT_READY:
2851 		case FORMAT_UNIT:		/* FIXME: correct? */
2852 		case SEND_DIAGNOSTIC:		/* FIXME: correct? */
2853 			ata_scsi_rbuf_fill(&args, ata_scsiop_noop);
2854 			break;
2855 
2856 		case INQUIRY:
2857 			if (scsicmd[1] & 2)	           /* is CmdDt set?  */
2858 				ata_scsi_invalid_field(cmd, done);
2859 			else if ((scsicmd[1] & 1) == 0)    /* is EVPD clear? */
2860 				ata_scsi_rbuf_fill(&args, ata_scsiop_inq_std);
2861 			else if (scsicmd[2] == 0x00)
2862 				ata_scsi_rbuf_fill(&args, ata_scsiop_inq_00);
2863 			else if (scsicmd[2] == 0x80)
2864 				ata_scsi_rbuf_fill(&args, ata_scsiop_inq_80);
2865 			else if (scsicmd[2] == 0x83)
2866 				ata_scsi_rbuf_fill(&args, ata_scsiop_inq_83);
2867 			else
2868 				ata_scsi_invalid_field(cmd, done);
2869 			break;
2870 
2871 		case MODE_SENSE:
2872 		case MODE_SENSE_10:
2873 			ata_scsi_rbuf_fill(&args, ata_scsiop_mode_sense);
2874 			break;
2875 
2876 		case MODE_SELECT:	/* unconditionally return */
2877 		case MODE_SELECT_10:	/* bad-field-in-cdb */
2878 			ata_scsi_invalid_field(cmd, done);
2879 			break;
2880 
2881 		case READ_CAPACITY:
2882 			ata_scsi_rbuf_fill(&args, ata_scsiop_read_cap);
2883 			break;
2884 
2885 		case SERVICE_ACTION_IN:
2886 			if ((scsicmd[1] & 0x1f) == SAI_READ_CAPACITY_16)
2887 				ata_scsi_rbuf_fill(&args, ata_scsiop_read_cap);
2888 			else
2889 				ata_scsi_invalid_field(cmd, done);
2890 			break;
2891 
2892 		case REPORT_LUNS:
2893 			ata_scsi_rbuf_fill(&args, ata_scsiop_report_luns);
2894 			break;
2895 
2896 		/* mandatory commands we haven't implemented yet */
2897 		case REQUEST_SENSE:
2898 
2899 		/* all other commands */
2900 		default:
2901 			ata_scsi_set_sense(cmd, ILLEGAL_REQUEST, 0x20, 0x0);
2902 			/* "Invalid command operation code" */
2903 			done(cmd);
2904 			break;
2905 	}
2906 }
2907 
2908 int ata_scsi_add_hosts(struct ata_host *host, struct scsi_host_template *sht)
2909 {
2910 	int i, rc;
2911 
2912 	for (i = 0; i < host->n_ports; i++) {
2913 		struct ata_port *ap = host->ports[i];
2914 		struct Scsi_Host *shost;
2915 
2916 		rc = -ENOMEM;
2917 		shost = scsi_host_alloc(sht, sizeof(struct ata_port *));
2918 		if (!shost)
2919 			goto err_alloc;
2920 
2921 		*(struct ata_port **)&shost->hostdata[0] = ap;
2922 		ap->scsi_host = shost;
2923 
2924 		shost->transportt = &ata_scsi_transport_template;
2925 		shost->unique_id = ap->print_id;
2926 		shost->max_id = 16;
2927 		shost->max_lun = 1;
2928 		shost->max_channel = 1;
2929 		shost->max_cmd_len = 16;
2930 
2931 		rc = scsi_add_host(ap->scsi_host, ap->host->dev);
2932 		if (rc)
2933 			goto err_add;
2934 	}
2935 
2936 	return 0;
2937 
2938  err_add:
2939 	scsi_host_put(host->ports[i]->scsi_host);
2940  err_alloc:
2941 	while (--i >= 0) {
2942 		struct Scsi_Host *shost = host->ports[i]->scsi_host;
2943 
2944 		scsi_remove_host(shost);
2945 		scsi_host_put(shost);
2946 	}
2947 	return rc;
2948 }
2949 
2950 void ata_scsi_scan_host(struct ata_port *ap)
2951 {
2952 	unsigned int i;
2953 
2954 	if (ap->flags & ATA_FLAG_DISABLED)
2955 		return;
2956 
2957 	for (i = 0; i < ATA_MAX_DEVICES; i++) {
2958 		struct ata_device *dev = &ap->device[i];
2959 		struct scsi_device *sdev;
2960 
2961 		if (!ata_dev_enabled(dev) || dev->sdev)
2962 			continue;
2963 
2964 		sdev = __scsi_add_device(ap->scsi_host, 0, i, 0, NULL);
2965 		if (!IS_ERR(sdev)) {
2966 			dev->sdev = sdev;
2967 			scsi_device_put(sdev);
2968 		}
2969 	}
2970 }
2971 
2972 /**
2973  *	ata_scsi_offline_dev - offline attached SCSI device
2974  *	@dev: ATA device to offline attached SCSI device for
2975  *
2976  *	This function is called from ata_eh_hotplug() and responsible
2977  *	for taking the SCSI device attached to @dev offline.  This
2978  *	function is called with host lock which protects dev->sdev
2979  *	against clearing.
2980  *
2981  *	LOCKING:
2982  *	spin_lock_irqsave(host lock)
2983  *
2984  *	RETURNS:
2985  *	1 if attached SCSI device exists, 0 otherwise.
2986  */
2987 int ata_scsi_offline_dev(struct ata_device *dev)
2988 {
2989 	if (dev->sdev) {
2990 		scsi_device_set_state(dev->sdev, SDEV_OFFLINE);
2991 		return 1;
2992 	}
2993 	return 0;
2994 }
2995 
2996 /**
2997  *	ata_scsi_remove_dev - remove attached SCSI device
2998  *	@dev: ATA device to remove attached SCSI device for
2999  *
3000  *	This function is called from ata_eh_scsi_hotplug() and
3001  *	responsible for removing the SCSI device attached to @dev.
3002  *
3003  *	LOCKING:
3004  *	Kernel thread context (may sleep).
3005  */
3006 static void ata_scsi_remove_dev(struct ata_device *dev)
3007 {
3008 	struct ata_port *ap = dev->ap;
3009 	struct scsi_device *sdev;
3010 	unsigned long flags;
3011 
3012 	/* Alas, we need to grab scan_mutex to ensure SCSI device
3013 	 * state doesn't change underneath us and thus
3014 	 * scsi_device_get() always succeeds.  The mutex locking can
3015 	 * be removed if there is __scsi_device_get() interface which
3016 	 * increments reference counts regardless of device state.
3017 	 */
3018 	mutex_lock(&ap->scsi_host->scan_mutex);
3019 	spin_lock_irqsave(ap->lock, flags);
3020 
3021 	/* clearing dev->sdev is protected by host lock */
3022 	sdev = dev->sdev;
3023 	dev->sdev = NULL;
3024 
3025 	if (sdev) {
3026 		/* If user initiated unplug races with us, sdev can go
3027 		 * away underneath us after the host lock and
3028 		 * scan_mutex are released.  Hold onto it.
3029 		 */
3030 		if (scsi_device_get(sdev) == 0) {
3031 			/* The following ensures the attached sdev is
3032 			 * offline on return from ata_scsi_offline_dev()
3033 			 * regardless it wins or loses the race
3034 			 * against this function.
3035 			 */
3036 			scsi_device_set_state(sdev, SDEV_OFFLINE);
3037 		} else {
3038 			WARN_ON(1);
3039 			sdev = NULL;
3040 		}
3041 	}
3042 
3043 	spin_unlock_irqrestore(ap->lock, flags);
3044 	mutex_unlock(&ap->scsi_host->scan_mutex);
3045 
3046 	if (sdev) {
3047 		ata_dev_printk(dev, KERN_INFO, "detaching (SCSI %s)\n",
3048 			       sdev->sdev_gendev.bus_id);
3049 
3050 		scsi_remove_device(sdev);
3051 		scsi_device_put(sdev);
3052 	}
3053 }
3054 
3055 /**
3056  *	ata_scsi_hotplug - SCSI part of hotplug
3057  *	@work: Pointer to ATA port to perform SCSI hotplug on
3058  *
3059  *	Perform SCSI part of hotplug.  It's executed from a separate
3060  *	workqueue after EH completes.  This is necessary because SCSI
3061  *	hot plugging requires working EH and hot unplugging is
3062  *	synchronized with hot plugging with a mutex.
3063  *
3064  *	LOCKING:
3065  *	Kernel thread context (may sleep).
3066  */
3067 void ata_scsi_hotplug(struct work_struct *work)
3068 {
3069 	struct ata_port *ap =
3070 		container_of(work, struct ata_port, hotplug_task.work);
3071 	int i;
3072 
3073 	if (ap->pflags & ATA_PFLAG_UNLOADING) {
3074 		DPRINTK("ENTER/EXIT - unloading\n");
3075 		return;
3076 	}
3077 
3078 	DPRINTK("ENTER\n");
3079 
3080 	/* unplug detached devices */
3081 	for (i = 0; i < ATA_MAX_DEVICES; i++) {
3082 		struct ata_device *dev = &ap->device[i];
3083 		unsigned long flags;
3084 
3085 		if (!(dev->flags & ATA_DFLAG_DETACHED))
3086 			continue;
3087 
3088 		spin_lock_irqsave(ap->lock, flags);
3089 		dev->flags &= ~ATA_DFLAG_DETACHED;
3090 		spin_unlock_irqrestore(ap->lock, flags);
3091 
3092 		ata_scsi_remove_dev(dev);
3093 	}
3094 
3095 	/* scan for new ones */
3096 	ata_scsi_scan_host(ap);
3097 
3098 	/* If we scanned while EH was in progress, scan would have
3099 	 * failed silently.  Requeue if there are enabled but
3100 	 * unattached devices.
3101 	 */
3102 	for (i = 0; i < ATA_MAX_DEVICES; i++) {
3103 		struct ata_device *dev = &ap->device[i];
3104 		if (ata_dev_enabled(dev) && !dev->sdev) {
3105 			queue_delayed_work(ata_aux_wq, &ap->hotplug_task,
3106 				round_jiffies_relative(HZ));
3107 			break;
3108 		}
3109 	}
3110 
3111 	DPRINTK("EXIT\n");
3112 }
3113 
3114 /**
3115  *	ata_scsi_user_scan - indication for user-initiated bus scan
3116  *	@shost: SCSI host to scan
3117  *	@channel: Channel to scan
3118  *	@id: ID to scan
3119  *	@lun: LUN to scan
3120  *
3121  *	This function is called when user explicitly requests bus
3122  *	scan.  Set probe pending flag and invoke EH.
3123  *
3124  *	LOCKING:
3125  *	SCSI layer (we don't care)
3126  *
3127  *	RETURNS:
3128  *	Zero.
3129  */
3130 static int ata_scsi_user_scan(struct Scsi_Host *shost, unsigned int channel,
3131 			      unsigned int id, unsigned int lun)
3132 {
3133 	struct ata_port *ap = ata_shost_to_port(shost);
3134 	unsigned long flags;
3135 	int rc = 0;
3136 
3137 	if (!ap->ops->error_handler)
3138 		return -EOPNOTSUPP;
3139 
3140 	if ((channel != SCAN_WILD_CARD && channel != 0) ||
3141 	    (lun != SCAN_WILD_CARD && lun != 0))
3142 		return -EINVAL;
3143 
3144 	spin_lock_irqsave(ap->lock, flags);
3145 
3146 	if (id == SCAN_WILD_CARD) {
3147 		ap->eh_info.probe_mask |= (1 << ATA_MAX_DEVICES) - 1;
3148 		ap->eh_info.action |= ATA_EH_SOFTRESET;
3149 	} else {
3150 		struct ata_device *dev = ata_find_dev(ap, id);
3151 
3152 		if (dev) {
3153 			ap->eh_info.probe_mask |= 1 << dev->devno;
3154 			ap->eh_info.action |= ATA_EH_SOFTRESET;
3155 			ap->eh_info.flags |= ATA_EHI_RESUME_LINK;
3156 		} else
3157 			rc = -EINVAL;
3158 	}
3159 
3160 	if (rc == 0) {
3161 		ata_port_schedule_eh(ap);
3162 		spin_unlock_irqrestore(ap->lock, flags);
3163 		ata_port_wait_eh(ap);
3164 	} else
3165 		spin_unlock_irqrestore(ap->lock, flags);
3166 
3167 	return rc;
3168 }
3169 
3170 /**
3171  *	ata_scsi_dev_rescan - initiate scsi_rescan_device()
3172  *	@work: Pointer to ATA port to perform scsi_rescan_device()
3173  *
3174  *	After ATA pass thru (SAT) commands are executed successfully,
3175  *	libata need to propagate the changes to SCSI layer.  This
3176  *	function must be executed from ata_aux_wq such that sdev
3177  *	attach/detach don't race with rescan.
3178  *
3179  *	LOCKING:
3180  *	Kernel thread context (may sleep).
3181  */
3182 void ata_scsi_dev_rescan(struct work_struct *work)
3183 {
3184 	struct ata_port *ap =
3185 		container_of(work, struct ata_port, scsi_rescan_task);
3186 	unsigned long flags;
3187 	unsigned int i;
3188 
3189 	spin_lock_irqsave(ap->lock, flags);
3190 
3191 	for (i = 0; i < ATA_MAX_DEVICES; i++) {
3192 		struct ata_device *dev = &ap->device[i];
3193 		struct scsi_device *sdev = dev->sdev;
3194 
3195 		if (!ata_dev_enabled(dev) || !sdev)
3196 			continue;
3197 		if (scsi_device_get(sdev))
3198 			continue;
3199 
3200 		spin_unlock_irqrestore(ap->lock, flags);
3201 		scsi_rescan_device(&(sdev->sdev_gendev));
3202 		scsi_device_put(sdev);
3203 		spin_lock_irqsave(ap->lock, flags);
3204 	}
3205 
3206 	spin_unlock_irqrestore(ap->lock, flags);
3207 }
3208 
3209 /**
3210  *	ata_sas_port_alloc - Allocate port for a SAS attached SATA device
3211  *	@host: ATA host container for all SAS ports
3212  *	@port_info: Information from low-level host driver
3213  *	@shost: SCSI host that the scsi device is attached to
3214  *
3215  *	LOCKING:
3216  *	PCI/etc. bus probe sem.
3217  *
3218  *	RETURNS:
3219  *	ata_port pointer on success / NULL on failure.
3220  */
3221 
3222 struct ata_port *ata_sas_port_alloc(struct ata_host *host,
3223 				    struct ata_port_info *port_info,
3224 				    struct Scsi_Host *shost)
3225 {
3226 	struct ata_port *ap;
3227 
3228 	ap = ata_port_alloc(host);
3229 	if (!ap)
3230 		return NULL;
3231 
3232 	ap->port_no = 0;
3233 	ap->lock = shost->host_lock;
3234 	ap->pio_mask = port_info->pio_mask;
3235 	ap->mwdma_mask = port_info->mwdma_mask;
3236 	ap->udma_mask = port_info->udma_mask;
3237 	ap->flags |= port_info->flags;
3238 	ap->ops = port_info->port_ops;
3239 	ap->cbl = ATA_CBL_SATA;
3240 
3241 	return ap;
3242 }
3243 EXPORT_SYMBOL_GPL(ata_sas_port_alloc);
3244 
3245 /**
3246  *	ata_sas_port_start - Set port up for dma.
3247  *	@ap: Port to initialize
3248  *
3249  *	Called just after data structures for each port are
3250  *	initialized.  Allocates DMA pad.
3251  *
3252  *	May be used as the port_start() entry in ata_port_operations.
3253  *
3254  *	LOCKING:
3255  *	Inherited from caller.
3256  */
3257 int ata_sas_port_start(struct ata_port *ap)
3258 {
3259 	return ata_pad_alloc(ap, ap->dev);
3260 }
3261 EXPORT_SYMBOL_GPL(ata_sas_port_start);
3262 
3263 /**
3264  *	ata_port_stop - Undo ata_sas_port_start()
3265  *	@ap: Port to shut down
3266  *
3267  *	Frees the DMA pad.
3268  *
3269  *	May be used as the port_stop() entry in ata_port_operations.
3270  *
3271  *	LOCKING:
3272  *	Inherited from caller.
3273  */
3274 
3275 void ata_sas_port_stop(struct ata_port *ap)
3276 {
3277 	ata_pad_free(ap, ap->dev);
3278 }
3279 EXPORT_SYMBOL_GPL(ata_sas_port_stop);
3280 
3281 /**
3282  *	ata_sas_port_init - Initialize a SATA device
3283  *	@ap: SATA port to initialize
3284  *
3285  *	LOCKING:
3286  *	PCI/etc. bus probe sem.
3287  *
3288  *	RETURNS:
3289  *	Zero on success, non-zero on error.
3290  */
3291 
3292 int ata_sas_port_init(struct ata_port *ap)
3293 {
3294 	int rc = ap->ops->port_start(ap);
3295 
3296 	if (!rc) {
3297 		ap->print_id = ata_print_id++;
3298 		rc = ata_bus_probe(ap);
3299 	}
3300 
3301 	return rc;
3302 }
3303 EXPORT_SYMBOL_GPL(ata_sas_port_init);
3304 
3305 /**
3306  *	ata_sas_port_destroy - Destroy a SATA port allocated by ata_sas_port_alloc
3307  *	@ap: SATA port to destroy
3308  *
3309  */
3310 
3311 void ata_sas_port_destroy(struct ata_port *ap)
3312 {
3313 	if (ap->ops->port_stop)
3314 		ap->ops->port_stop(ap);
3315 	kfree(ap);
3316 }
3317 EXPORT_SYMBOL_GPL(ata_sas_port_destroy);
3318 
3319 /**
3320  *	ata_sas_slave_configure - Default slave_config routine for libata devices
3321  *	@sdev: SCSI device to configure
3322  *	@ap: ATA port to which SCSI device is attached
3323  *
3324  *	RETURNS:
3325  *	Zero.
3326  */
3327 
3328 int ata_sas_slave_configure(struct scsi_device *sdev, struct ata_port *ap)
3329 {
3330 	ata_scsi_sdev_config(sdev);
3331 	ata_scsi_dev_config(sdev, ap->device);
3332 	return 0;
3333 }
3334 EXPORT_SYMBOL_GPL(ata_sas_slave_configure);
3335 
3336 /**
3337  *	ata_sas_queuecmd - Issue SCSI cdb to libata-managed device
3338  *	@cmd: SCSI command to be sent
3339  *	@done: Completion function, called when command is complete
3340  *	@ap:	ATA port to which the command is being sent
3341  *
3342  *	RETURNS:
3343  *	Return value from __ata_scsi_queuecmd() if @cmd can be queued,
3344  *	0 otherwise.
3345  */
3346 
3347 int ata_sas_queuecmd(struct scsi_cmnd *cmd, void (*done)(struct scsi_cmnd *),
3348 		     struct ata_port *ap)
3349 {
3350 	int rc = 0;
3351 
3352 	ata_scsi_dump_cdb(ap, cmd);
3353 
3354 	if (likely(ata_scsi_dev_enabled(ap->device)))
3355 		rc = __ata_scsi_queuecmd(cmd, done, ap->device);
3356 	else {
3357 		cmd->result = (DID_BAD_TARGET << 16);
3358 		done(cmd);
3359 	}
3360 	return rc;
3361 }
3362 EXPORT_SYMBOL_GPL(ata_sas_queuecmd);
3363