xref: /openbmc/linux/drivers/ata/libata-scsi.c (revision a09d2831)
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 <linux/uaccess.h>
49 #include <linux/suspend.h>
50 #include <asm/unaligned.h>
51 
52 #include "libata.h"
53 
54 #define SECTOR_SIZE		512
55 #define ATA_SCSI_RBUF_SIZE	4096
56 
57 static DEFINE_SPINLOCK(ata_scsi_rbuf_lock);
58 static u8 ata_scsi_rbuf[ATA_SCSI_RBUF_SIZE];
59 
60 typedef unsigned int (*ata_xlat_func_t)(struct ata_queued_cmd *qc);
61 
62 static struct ata_device *__ata_scsi_find_dev(struct ata_port *ap,
63 					const struct scsi_device *scsidev);
64 static struct ata_device *ata_scsi_find_dev(struct ata_port *ap,
65 					    const struct scsi_device *scsidev);
66 static int ata_scsi_user_scan(struct Scsi_Host *shost, unsigned int channel,
67 			      unsigned int id, unsigned int lun);
68 
69 
70 #define RW_RECOVERY_MPAGE 0x1
71 #define RW_RECOVERY_MPAGE_LEN 12
72 #define CACHE_MPAGE 0x8
73 #define CACHE_MPAGE_LEN 20
74 #define CONTROL_MPAGE 0xa
75 #define CONTROL_MPAGE_LEN 12
76 #define ALL_MPAGES 0x3f
77 #define ALL_SUB_MPAGES 0xff
78 
79 
80 static const u8 def_rw_recovery_mpage[RW_RECOVERY_MPAGE_LEN] = {
81 	RW_RECOVERY_MPAGE,
82 	RW_RECOVERY_MPAGE_LEN - 2,
83 	(1 << 7),	/* AWRE */
84 	0,		/* read retry count */
85 	0, 0, 0, 0,
86 	0,		/* write retry count */
87 	0, 0, 0
88 };
89 
90 static const u8 def_cache_mpage[CACHE_MPAGE_LEN] = {
91 	CACHE_MPAGE,
92 	CACHE_MPAGE_LEN - 2,
93 	0,		/* contains WCE, needs to be 0 for logic */
94 	0, 0, 0, 0, 0, 0, 0, 0, 0,
95 	0,		/* contains DRA, needs to be 0 for logic */
96 	0, 0, 0, 0, 0, 0, 0
97 };
98 
99 static const u8 def_control_mpage[CONTROL_MPAGE_LEN] = {
100 	CONTROL_MPAGE,
101 	CONTROL_MPAGE_LEN - 2,
102 	2,	/* DSENSE=0, GLTSD=1 */
103 	0,	/* [QAM+QERR may be 1, see 05-359r1] */
104 	0, 0, 0, 0, 0xff, 0xff,
105 	0, 30	/* extended self test time, see 05-359r1 */
106 };
107 
108 /*
109  * libata transport template.  libata doesn't do real transport stuff.
110  * It just needs the eh_timed_out hook.
111  */
112 static struct scsi_transport_template ata_scsi_transport_template = {
113 	.eh_strategy_handler	= ata_scsi_error,
114 	.eh_timed_out		= ata_scsi_timed_out,
115 	.user_scan		= ata_scsi_user_scan,
116 };
117 
118 
119 static const struct {
120 	enum link_pm	value;
121 	const char	*name;
122 } link_pm_policy[] = {
123 	{ NOT_AVAILABLE, "max_performance" },
124 	{ MIN_POWER, "min_power" },
125 	{ MAX_PERFORMANCE, "max_performance" },
126 	{ MEDIUM_POWER, "medium_power" },
127 };
128 
129 static const char *ata_scsi_lpm_get(enum link_pm policy)
130 {
131 	int i;
132 
133 	for (i = 0; i < ARRAY_SIZE(link_pm_policy); i++)
134 		if (link_pm_policy[i].value == policy)
135 			return link_pm_policy[i].name;
136 
137 	return NULL;
138 }
139 
140 static ssize_t ata_scsi_lpm_put(struct device *dev,
141 				struct device_attribute *attr,
142 				const char *buf, size_t count)
143 {
144 	struct Scsi_Host *shost = class_to_shost(dev);
145 	struct ata_port *ap = ata_shost_to_port(shost);
146 	enum link_pm policy = 0;
147 	int i;
148 
149 	/*
150 	 * we are skipping array location 0 on purpose - this
151 	 * is because a value of NOT_AVAILABLE is displayed
152 	 * to the user as max_performance, but when the user
153 	 * writes "max_performance", they actually want the
154 	 * value to match MAX_PERFORMANCE.
155 	 */
156 	for (i = 1; i < ARRAY_SIZE(link_pm_policy); i++) {
157 		const int len = strlen(link_pm_policy[i].name);
158 		if (strncmp(link_pm_policy[i].name, buf, len) == 0) {
159 			policy = link_pm_policy[i].value;
160 			break;
161 		}
162 	}
163 	if (!policy)
164 		return -EINVAL;
165 
166 	ata_lpm_schedule(ap, policy);
167 	return count;
168 }
169 
170 static ssize_t
171 ata_scsi_lpm_show(struct device *dev, struct device_attribute *attr, char *buf)
172 {
173 	struct Scsi_Host *shost = class_to_shost(dev);
174 	struct ata_port *ap = ata_shost_to_port(shost);
175 	const char *policy =
176 		ata_scsi_lpm_get(ap->pm_policy);
177 
178 	if (!policy)
179 		return -EINVAL;
180 
181 	return snprintf(buf, 23, "%s\n", policy);
182 }
183 DEVICE_ATTR(link_power_management_policy, S_IRUGO | S_IWUSR,
184 		ata_scsi_lpm_show, ata_scsi_lpm_put);
185 EXPORT_SYMBOL_GPL(dev_attr_link_power_management_policy);
186 
187 static ssize_t ata_scsi_park_show(struct device *device,
188 				  struct device_attribute *attr, char *buf)
189 {
190 	struct scsi_device *sdev = to_scsi_device(device);
191 	struct ata_port *ap;
192 	struct ata_link *link;
193 	struct ata_device *dev;
194 	unsigned long flags, now;
195 	unsigned int uninitialized_var(msecs);
196 	int rc = 0;
197 
198 	ap = ata_shost_to_port(sdev->host);
199 
200 	spin_lock_irqsave(ap->lock, flags);
201 	dev = ata_scsi_find_dev(ap, sdev);
202 	if (!dev) {
203 		rc = -ENODEV;
204 		goto unlock;
205 	}
206 	if (dev->flags & ATA_DFLAG_NO_UNLOAD) {
207 		rc = -EOPNOTSUPP;
208 		goto unlock;
209 	}
210 
211 	link = dev->link;
212 	now = jiffies;
213 	if (ap->pflags & ATA_PFLAG_EH_IN_PROGRESS &&
214 	    link->eh_context.unloaded_mask & (1 << dev->devno) &&
215 	    time_after(dev->unpark_deadline, now))
216 		msecs = jiffies_to_msecs(dev->unpark_deadline - now);
217 	else
218 		msecs = 0;
219 
220 unlock:
221 	spin_unlock_irq(ap->lock);
222 
223 	return rc ? rc : snprintf(buf, 20, "%u\n", msecs);
224 }
225 
226 static ssize_t ata_scsi_park_store(struct device *device,
227 				   struct device_attribute *attr,
228 				   const char *buf, size_t len)
229 {
230 	struct scsi_device *sdev = to_scsi_device(device);
231 	struct ata_port *ap;
232 	struct ata_device *dev;
233 	long int input;
234 	unsigned long flags;
235 	int rc;
236 
237 	rc = strict_strtol(buf, 10, &input);
238 	if (rc || input < -2)
239 		return -EINVAL;
240 	if (input > ATA_TMOUT_MAX_PARK) {
241 		rc = -EOVERFLOW;
242 		input = ATA_TMOUT_MAX_PARK;
243 	}
244 
245 	ap = ata_shost_to_port(sdev->host);
246 
247 	spin_lock_irqsave(ap->lock, flags);
248 	dev = ata_scsi_find_dev(ap, sdev);
249 	if (unlikely(!dev)) {
250 		rc = -ENODEV;
251 		goto unlock;
252 	}
253 	if (dev->class != ATA_DEV_ATA) {
254 		rc = -EOPNOTSUPP;
255 		goto unlock;
256 	}
257 
258 	if (input >= 0) {
259 		if (dev->flags & ATA_DFLAG_NO_UNLOAD) {
260 			rc = -EOPNOTSUPP;
261 			goto unlock;
262 		}
263 
264 		dev->unpark_deadline = ata_deadline(jiffies, input);
265 		dev->link->eh_info.dev_action[dev->devno] |= ATA_EH_PARK;
266 		ata_port_schedule_eh(ap);
267 		complete(&ap->park_req_pending);
268 	} else {
269 		switch (input) {
270 		case -1:
271 			dev->flags &= ~ATA_DFLAG_NO_UNLOAD;
272 			break;
273 		case -2:
274 			dev->flags |= ATA_DFLAG_NO_UNLOAD;
275 			break;
276 		}
277 	}
278 unlock:
279 	spin_unlock_irqrestore(ap->lock, flags);
280 
281 	return rc ? rc : len;
282 }
283 DEVICE_ATTR(unload_heads, S_IRUGO | S_IWUSR,
284 	    ata_scsi_park_show, ata_scsi_park_store);
285 EXPORT_SYMBOL_GPL(dev_attr_unload_heads);
286 
287 static void ata_scsi_set_sense(struct scsi_cmnd *cmd, u8 sk, u8 asc, u8 ascq)
288 {
289 	cmd->result = (DRIVER_SENSE << 24) | SAM_STAT_CHECK_CONDITION;
290 
291 	scsi_build_sense_buffer(0, cmd->sense_buffer, sk, asc, ascq);
292 }
293 
294 static ssize_t
295 ata_scsi_em_message_store(struct device *dev, struct device_attribute *attr,
296 			  const char *buf, size_t count)
297 {
298 	struct Scsi_Host *shost = class_to_shost(dev);
299 	struct ata_port *ap = ata_shost_to_port(shost);
300 	if (ap->ops->em_store && (ap->flags & ATA_FLAG_EM))
301 		return ap->ops->em_store(ap, buf, count);
302 	return -EINVAL;
303 }
304 
305 static ssize_t
306 ata_scsi_em_message_show(struct device *dev, struct device_attribute *attr,
307 			 char *buf)
308 {
309 	struct Scsi_Host *shost = class_to_shost(dev);
310 	struct ata_port *ap = ata_shost_to_port(shost);
311 
312 	if (ap->ops->em_show && (ap->flags & ATA_FLAG_EM))
313 		return ap->ops->em_show(ap, buf);
314 	return -EINVAL;
315 }
316 DEVICE_ATTR(em_message, S_IRUGO | S_IWUSR,
317 		ata_scsi_em_message_show, ata_scsi_em_message_store);
318 EXPORT_SYMBOL_GPL(dev_attr_em_message);
319 
320 static ssize_t
321 ata_scsi_em_message_type_show(struct device *dev, struct device_attribute *attr,
322 			      char *buf)
323 {
324 	struct Scsi_Host *shost = class_to_shost(dev);
325 	struct ata_port *ap = ata_shost_to_port(shost);
326 
327 	return snprintf(buf, 23, "%d\n", ap->em_message_type);
328 }
329 DEVICE_ATTR(em_message_type, S_IRUGO,
330 		  ata_scsi_em_message_type_show, NULL);
331 EXPORT_SYMBOL_GPL(dev_attr_em_message_type);
332 
333 static ssize_t
334 ata_scsi_activity_show(struct device *dev, struct device_attribute *attr,
335 		char *buf)
336 {
337 	struct scsi_device *sdev = to_scsi_device(dev);
338 	struct ata_port *ap = ata_shost_to_port(sdev->host);
339 	struct ata_device *atadev = ata_scsi_find_dev(ap, sdev);
340 
341 	if (ap->ops->sw_activity_show && (ap->flags & ATA_FLAG_SW_ACTIVITY))
342 		return ap->ops->sw_activity_show(atadev, buf);
343 	return -EINVAL;
344 }
345 
346 static ssize_t
347 ata_scsi_activity_store(struct device *dev, struct device_attribute *attr,
348 	const char *buf, size_t count)
349 {
350 	struct scsi_device *sdev = to_scsi_device(dev);
351 	struct ata_port *ap = ata_shost_to_port(sdev->host);
352 	struct ata_device *atadev = ata_scsi_find_dev(ap, sdev);
353 	enum sw_activity val;
354 	int rc;
355 
356 	if (ap->ops->sw_activity_store && (ap->flags & ATA_FLAG_SW_ACTIVITY)) {
357 		val = simple_strtoul(buf, NULL, 0);
358 		switch (val) {
359 		case OFF: case BLINK_ON: case BLINK_OFF:
360 			rc = ap->ops->sw_activity_store(atadev, val);
361 			if (!rc)
362 				return count;
363 			else
364 				return rc;
365 		}
366 	}
367 	return -EINVAL;
368 }
369 DEVICE_ATTR(sw_activity, S_IWUSR | S_IRUGO, ata_scsi_activity_show,
370 			ata_scsi_activity_store);
371 EXPORT_SYMBOL_GPL(dev_attr_sw_activity);
372 
373 struct device_attribute *ata_common_sdev_attrs[] = {
374 	&dev_attr_unload_heads,
375 	NULL
376 };
377 EXPORT_SYMBOL_GPL(ata_common_sdev_attrs);
378 
379 static void ata_scsi_invalid_field(struct scsi_cmnd *cmd,
380 				   void (*done)(struct scsi_cmnd *))
381 {
382 	ata_scsi_set_sense(cmd, ILLEGAL_REQUEST, 0x24, 0x0);
383 	/* "Invalid field in cbd" */
384 	done(cmd);
385 }
386 
387 /**
388  *	ata_std_bios_param - generic bios head/sector/cylinder calculator used by sd.
389  *	@sdev: SCSI device for which BIOS geometry is to be determined
390  *	@bdev: block device associated with @sdev
391  *	@capacity: capacity of SCSI device
392  *	@geom: location to which geometry will be output
393  *
394  *	Generic bios head/sector/cylinder calculator
395  *	used by sd. Most BIOSes nowadays expect a XXX/255/16  (CHS)
396  *	mapping. Some situations may arise where the disk is not
397  *	bootable if this is not used.
398  *
399  *	LOCKING:
400  *	Defined by the SCSI layer.  We don't really care.
401  *
402  *	RETURNS:
403  *	Zero.
404  */
405 int ata_std_bios_param(struct scsi_device *sdev, struct block_device *bdev,
406 		       sector_t capacity, int geom[])
407 {
408 	geom[0] = 255;
409 	geom[1] = 63;
410 	sector_div(capacity, 255*63);
411 	geom[2] = capacity;
412 
413 	return 0;
414 }
415 
416 /**
417  *	ata_get_identity - Handler for HDIO_GET_IDENTITY ioctl
418  *	@ap: target port
419  *	@sdev: SCSI device to get identify data for
420  *	@arg: User buffer area for identify data
421  *
422  *	LOCKING:
423  *	Defined by the SCSI layer.  We don't really care.
424  *
425  *	RETURNS:
426  *	Zero on success, negative errno on error.
427  */
428 static int ata_get_identity(struct ata_port *ap, struct scsi_device *sdev,
429 			    void __user *arg)
430 {
431 	struct ata_device *dev = ata_scsi_find_dev(ap, sdev);
432 	u16 __user *dst = arg;
433 	char buf[40];
434 
435 	if (!dev)
436 		return -ENOMSG;
437 
438 	if (copy_to_user(dst, dev->id, ATA_ID_WORDS * sizeof(u16)))
439 		return -EFAULT;
440 
441 	ata_id_string(dev->id, buf, ATA_ID_PROD, ATA_ID_PROD_LEN);
442 	if (copy_to_user(dst + ATA_ID_PROD, buf, ATA_ID_PROD_LEN))
443 		return -EFAULT;
444 
445 	ata_id_string(dev->id, buf, ATA_ID_FW_REV, ATA_ID_FW_REV_LEN);
446 	if (copy_to_user(dst + ATA_ID_FW_REV, buf, ATA_ID_FW_REV_LEN))
447 		return -EFAULT;
448 
449 	ata_id_string(dev->id, buf, ATA_ID_SERNO, ATA_ID_SERNO_LEN);
450 	if (copy_to_user(dst + ATA_ID_SERNO, buf, ATA_ID_SERNO_LEN))
451 		return -EFAULT;
452 
453 	return 0;
454 }
455 
456 /**
457  *	ata_cmd_ioctl - Handler for HDIO_DRIVE_CMD ioctl
458  *	@scsidev: Device to which we are issuing command
459  *	@arg: User provided data for issuing command
460  *
461  *	LOCKING:
462  *	Defined by the SCSI layer.  We don't really care.
463  *
464  *	RETURNS:
465  *	Zero on success, negative errno on error.
466  */
467 int ata_cmd_ioctl(struct scsi_device *scsidev, void __user *arg)
468 {
469 	int rc = 0;
470 	u8 scsi_cmd[MAX_COMMAND_SIZE];
471 	u8 args[4], *argbuf = NULL, *sensebuf = NULL;
472 	int argsize = 0;
473 	enum dma_data_direction data_dir;
474 	int cmd_result;
475 
476 	if (arg == NULL)
477 		return -EINVAL;
478 
479 	if (copy_from_user(args, arg, sizeof(args)))
480 		return -EFAULT;
481 
482 	sensebuf = kzalloc(SCSI_SENSE_BUFFERSIZE, GFP_NOIO);
483 	if (!sensebuf)
484 		return -ENOMEM;
485 
486 	memset(scsi_cmd, 0, sizeof(scsi_cmd));
487 
488 	if (args[3]) {
489 		argsize = SECTOR_SIZE * args[3];
490 		argbuf = kmalloc(argsize, GFP_KERNEL);
491 		if (argbuf == NULL) {
492 			rc = -ENOMEM;
493 			goto error;
494 		}
495 
496 		scsi_cmd[1]  = (4 << 1); /* PIO Data-in */
497 		scsi_cmd[2]  = 0x0e;     /* no off.line or cc, read from dev,
498 					    block count in sector count field */
499 		data_dir = DMA_FROM_DEVICE;
500 	} else {
501 		scsi_cmd[1]  = (3 << 1); /* Non-data */
502 		scsi_cmd[2]  = 0x20;     /* cc but no off.line or data xfer */
503 		data_dir = DMA_NONE;
504 	}
505 
506 	scsi_cmd[0] = ATA_16;
507 
508 	scsi_cmd[4] = args[2];
509 	if (args[0] == ATA_CMD_SMART) { /* hack -- ide driver does this too */
510 		scsi_cmd[6]  = args[3];
511 		scsi_cmd[8]  = args[1];
512 		scsi_cmd[10] = 0x4f;
513 		scsi_cmd[12] = 0xc2;
514 	} else {
515 		scsi_cmd[6]  = args[1];
516 	}
517 	scsi_cmd[14] = args[0];
518 
519 	/* Good values for timeout and retries?  Values below
520 	   from scsi_ioctl_send_command() for default case... */
521 	cmd_result = scsi_execute(scsidev, scsi_cmd, data_dir, argbuf, argsize,
522 				  sensebuf, (10*HZ), 5, 0, NULL);
523 
524 	if (driver_byte(cmd_result) == DRIVER_SENSE) {/* sense data available */
525 		u8 *desc = sensebuf + 8;
526 		cmd_result &= ~(0xFF<<24); /* DRIVER_SENSE is not an error */
527 
528 		/* If we set cc then ATA pass-through will cause a
529 		 * check condition even if no error. Filter that. */
530 		if (cmd_result & SAM_STAT_CHECK_CONDITION) {
531 			struct scsi_sense_hdr sshdr;
532 			scsi_normalize_sense(sensebuf, SCSI_SENSE_BUFFERSIZE,
533 					     &sshdr);
534 			if (sshdr.sense_key == 0 &&
535 			    sshdr.asc == 0 && sshdr.ascq == 0)
536 				cmd_result &= ~SAM_STAT_CHECK_CONDITION;
537 		}
538 
539 		/* Send userspace a few ATA registers (same as drivers/ide) */
540 		if (sensebuf[0] == 0x72 &&	/* format is "descriptor" */
541 		    desc[0] == 0x09) {		/* code is "ATA Descriptor" */
542 			args[0] = desc[13];	/* status */
543 			args[1] = desc[3];	/* error */
544 			args[2] = desc[5];	/* sector count (0:7) */
545 			if (copy_to_user(arg, args, sizeof(args)))
546 				rc = -EFAULT;
547 		}
548 	}
549 
550 
551 	if (cmd_result) {
552 		rc = -EIO;
553 		goto error;
554 	}
555 
556 	if ((argbuf)
557 	 && copy_to_user(arg + sizeof(args), argbuf, argsize))
558 		rc = -EFAULT;
559 error:
560 	kfree(sensebuf);
561 	kfree(argbuf);
562 	return rc;
563 }
564 
565 /**
566  *	ata_task_ioctl - Handler for HDIO_DRIVE_TASK ioctl
567  *	@scsidev: Device to which we are issuing command
568  *	@arg: User provided data for issuing command
569  *
570  *	LOCKING:
571  *	Defined by the SCSI layer.  We don't really care.
572  *
573  *	RETURNS:
574  *	Zero on success, negative errno on error.
575  */
576 int ata_task_ioctl(struct scsi_device *scsidev, void __user *arg)
577 {
578 	int rc = 0;
579 	u8 scsi_cmd[MAX_COMMAND_SIZE];
580 	u8 args[7], *sensebuf = NULL;
581 	int cmd_result;
582 
583 	if (arg == NULL)
584 		return -EINVAL;
585 
586 	if (copy_from_user(args, arg, sizeof(args)))
587 		return -EFAULT;
588 
589 	sensebuf = kzalloc(SCSI_SENSE_BUFFERSIZE, GFP_NOIO);
590 	if (!sensebuf)
591 		return -ENOMEM;
592 
593 	memset(scsi_cmd, 0, sizeof(scsi_cmd));
594 	scsi_cmd[0]  = ATA_16;
595 	scsi_cmd[1]  = (3 << 1); /* Non-data */
596 	scsi_cmd[2]  = 0x20;     /* cc but no off.line or data xfer */
597 	scsi_cmd[4]  = args[1];
598 	scsi_cmd[6]  = args[2];
599 	scsi_cmd[8]  = args[3];
600 	scsi_cmd[10] = args[4];
601 	scsi_cmd[12] = args[5];
602 	scsi_cmd[13] = args[6] & 0x4f;
603 	scsi_cmd[14] = args[0];
604 
605 	/* Good values for timeout and retries?  Values below
606 	   from scsi_ioctl_send_command() for default case... */
607 	cmd_result = scsi_execute(scsidev, scsi_cmd, DMA_NONE, NULL, 0,
608 				sensebuf, (10*HZ), 5, 0, NULL);
609 
610 	if (driver_byte(cmd_result) == DRIVER_SENSE) {/* sense data available */
611 		u8 *desc = sensebuf + 8;
612 		cmd_result &= ~(0xFF<<24); /* DRIVER_SENSE is not an error */
613 
614 		/* If we set cc then ATA pass-through will cause a
615 		 * check condition even if no error. Filter that. */
616 		if (cmd_result & SAM_STAT_CHECK_CONDITION) {
617 			struct scsi_sense_hdr sshdr;
618 			scsi_normalize_sense(sensebuf, SCSI_SENSE_BUFFERSIZE,
619 						&sshdr);
620 			if (sshdr.sense_key == 0 &&
621 				sshdr.asc == 0 && sshdr.ascq == 0)
622 				cmd_result &= ~SAM_STAT_CHECK_CONDITION;
623 		}
624 
625 		/* Send userspace ATA registers */
626 		if (sensebuf[0] == 0x72 &&	/* format is "descriptor" */
627 				desc[0] == 0x09) {/* code is "ATA Descriptor" */
628 			args[0] = desc[13];	/* status */
629 			args[1] = desc[3];	/* error */
630 			args[2] = desc[5];	/* sector count (0:7) */
631 			args[3] = desc[7];	/* lbal */
632 			args[4] = desc[9];	/* lbam */
633 			args[5] = desc[11];	/* lbah */
634 			args[6] = desc[12];	/* select */
635 			if (copy_to_user(arg, args, sizeof(args)))
636 				rc = -EFAULT;
637 		}
638 	}
639 
640 	if (cmd_result) {
641 		rc = -EIO;
642 		goto error;
643 	}
644 
645  error:
646 	kfree(sensebuf);
647 	return rc;
648 }
649 
650 static int ata_ioc32(struct ata_port *ap)
651 {
652 	if (ap->flags & ATA_FLAG_PIO_DMA)
653 		return 1;
654 	if (ap->pflags & ATA_PFLAG_PIO32)
655 		return 1;
656 	return 0;
657 }
658 
659 int ata_sas_scsi_ioctl(struct ata_port *ap, struct scsi_device *scsidev,
660 		     int cmd, void __user *arg)
661 {
662 	int val = -EINVAL, rc = -EINVAL;
663 	unsigned long flags;
664 
665 	switch (cmd) {
666 	case ATA_IOC_GET_IO32:
667 		spin_lock_irqsave(ap->lock, flags);
668 		val = ata_ioc32(ap);
669 		spin_unlock_irqrestore(ap->lock, flags);
670 		if (copy_to_user(arg, &val, 1))
671 			return -EFAULT;
672 		return 0;
673 
674 	case ATA_IOC_SET_IO32:
675 		val = (unsigned long) arg;
676 		rc = 0;
677 		spin_lock_irqsave(ap->lock, flags);
678 		if (ap->pflags & ATA_PFLAG_PIO32CHANGE) {
679 			if (val)
680 				ap->pflags |= ATA_PFLAG_PIO32;
681 			else
682 				ap->pflags &= ~ATA_PFLAG_PIO32;
683 		} else {
684 			if (val != ata_ioc32(ap))
685 				rc = -EINVAL;
686 		}
687 		spin_unlock_irqrestore(ap->lock, flags);
688 		return rc;
689 
690 	case HDIO_GET_IDENTITY:
691 		return ata_get_identity(ap, scsidev, arg);
692 
693 	case HDIO_DRIVE_CMD:
694 		if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
695 			return -EACCES;
696 		return ata_cmd_ioctl(scsidev, arg);
697 
698 	case HDIO_DRIVE_TASK:
699 		if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
700 			return -EACCES;
701 		return ata_task_ioctl(scsidev, arg);
702 
703 	default:
704 		rc = -ENOTTY;
705 		break;
706 	}
707 
708 	return rc;
709 }
710 EXPORT_SYMBOL_GPL(ata_sas_scsi_ioctl);
711 
712 int ata_scsi_ioctl(struct scsi_device *scsidev, int cmd, void __user *arg)
713 {
714 	return ata_sas_scsi_ioctl(ata_shost_to_port(scsidev->host),
715 				scsidev, cmd, arg);
716 }
717 EXPORT_SYMBOL_GPL(ata_scsi_ioctl);
718 
719 /**
720  *	ata_scsi_qc_new - acquire new ata_queued_cmd reference
721  *	@dev: ATA device to which the new command is attached
722  *	@cmd: SCSI command that originated this ATA command
723  *	@done: SCSI command completion function
724  *
725  *	Obtain a reference to an unused ata_queued_cmd structure,
726  *	which is the basic libata structure representing a single
727  *	ATA command sent to the hardware.
728  *
729  *	If a command was available, fill in the SCSI-specific
730  *	portions of the structure with information on the
731  *	current command.
732  *
733  *	LOCKING:
734  *	spin_lock_irqsave(host lock)
735  *
736  *	RETURNS:
737  *	Command allocated, or %NULL if none available.
738  */
739 static struct ata_queued_cmd *ata_scsi_qc_new(struct ata_device *dev,
740 					      struct scsi_cmnd *cmd,
741 					      void (*done)(struct scsi_cmnd *))
742 {
743 	struct ata_queued_cmd *qc;
744 
745 	qc = ata_qc_new_init(dev);
746 	if (qc) {
747 		qc->scsicmd = cmd;
748 		qc->scsidone = done;
749 
750 		qc->sg = scsi_sglist(cmd);
751 		qc->n_elem = scsi_sg_count(cmd);
752 	} else {
753 		cmd->result = (DID_OK << 16) | (QUEUE_FULL << 1);
754 		done(cmd);
755 	}
756 
757 	return qc;
758 }
759 
760 static void ata_qc_set_pc_nbytes(struct ata_queued_cmd *qc)
761 {
762 	struct scsi_cmnd *scmd = qc->scsicmd;
763 
764 	qc->extrabytes = scmd->request->extra_len;
765 	qc->nbytes = scsi_bufflen(scmd) + qc->extrabytes;
766 }
767 
768 /**
769  *	ata_dump_status - user friendly display of error info
770  *	@id: id of the port in question
771  *	@tf: ptr to filled out taskfile
772  *
773  *	Decode and dump the ATA error/status registers for the user so
774  *	that they have some idea what really happened at the non
775  *	make-believe layer.
776  *
777  *	LOCKING:
778  *	inherited from caller
779  */
780 static void ata_dump_status(unsigned id, struct ata_taskfile *tf)
781 {
782 	u8 stat = tf->command, err = tf->feature;
783 
784 	printk(KERN_WARNING "ata%u: status=0x%02x { ", id, stat);
785 	if (stat & ATA_BUSY) {
786 		printk("Busy }\n");	/* Data is not valid in this case */
787 	} else {
788 		if (stat & 0x40)	printk("DriveReady ");
789 		if (stat & 0x20)	printk("DeviceFault ");
790 		if (stat & 0x10)	printk("SeekComplete ");
791 		if (stat & 0x08)	printk("DataRequest ");
792 		if (stat & 0x04)	printk("CorrectedError ");
793 		if (stat & 0x02)	printk("Index ");
794 		if (stat & 0x01)	printk("Error ");
795 		printk("}\n");
796 
797 		if (err) {
798 			printk(KERN_WARNING "ata%u: error=0x%02x { ", id, err);
799 			if (err & 0x04)		printk("DriveStatusError ");
800 			if (err & 0x80) {
801 				if (err & 0x04)	printk("BadCRC ");
802 				else		printk("Sector ");
803 			}
804 			if (err & 0x40)		printk("UncorrectableError ");
805 			if (err & 0x10)		printk("SectorIdNotFound ");
806 			if (err & 0x02)		printk("TrackZeroNotFound ");
807 			if (err & 0x01)		printk("AddrMarkNotFound ");
808 			printk("}\n");
809 		}
810 	}
811 }
812 
813 /**
814  *	ata_to_sense_error - convert ATA error to SCSI error
815  *	@id: ATA device number
816  *	@drv_stat: value contained in ATA status register
817  *	@drv_err: value contained in ATA error register
818  *	@sk: the sense key we'll fill out
819  *	@asc: the additional sense code we'll fill out
820  *	@ascq: the additional sense code qualifier we'll fill out
821  *	@verbose: be verbose
822  *
823  *	Converts an ATA error into a SCSI error.  Fill out pointers to
824  *	SK, ASC, and ASCQ bytes for later use in fixed or descriptor
825  *	format sense blocks.
826  *
827  *	LOCKING:
828  *	spin_lock_irqsave(host lock)
829  */
830 static void ata_to_sense_error(unsigned id, u8 drv_stat, u8 drv_err, u8 *sk,
831 			       u8 *asc, u8 *ascq, int verbose)
832 {
833 	int i;
834 
835 	/* Based on the 3ware driver translation table */
836 	static const unsigned char sense_table[][4] = {
837 		/* BBD|ECC|ID|MAR */
838 		{0xd1, 		ABORTED_COMMAND, 0x00, 0x00}, 	// Device busy                  Aborted command
839 		/* BBD|ECC|ID */
840 		{0xd0,  	ABORTED_COMMAND, 0x00, 0x00}, 	// Device busy                  Aborted command
841 		/* ECC|MC|MARK */
842 		{0x61, 		HARDWARE_ERROR, 0x00, 0x00}, 	// Device fault                 Hardware error
843 		/* ICRC|ABRT */		/* NB: ICRC & !ABRT is BBD */
844 		{0x84, 		ABORTED_COMMAND, 0x47, 0x00}, 	// Data CRC error               SCSI parity error
845 		/* MC|ID|ABRT|TRK0|MARK */
846 		{0x37, 		NOT_READY, 0x04, 0x00}, 	// Unit offline                 Not ready
847 		/* MCR|MARK */
848 		{0x09, 		NOT_READY, 0x04, 0x00}, 	// Unrecovered disk error       Not ready
849 		/*  Bad address mark */
850 		{0x01, 		MEDIUM_ERROR, 0x13, 0x00}, 	// Address mark not found       Address mark not found for data field
851 		/* TRK0 */
852 		{0x02, 		HARDWARE_ERROR, 0x00, 0x00}, 	// Track 0 not found		  Hardware error
853 		/* Abort & !ICRC */
854 		{0x04, 		ABORTED_COMMAND, 0x00, 0x00}, 	// Aborted command              Aborted command
855 		/* Media change request */
856 		{0x08, 		NOT_READY, 0x04, 0x00}, 	// Media change request	  FIXME: faking offline
857 		/* SRV */
858 		{0x10, 		ABORTED_COMMAND, 0x14, 0x00}, 	// ID not found                 Recorded entity not found
859 		/* Media change */
860 		{0x08,  	NOT_READY, 0x04, 0x00}, 	// Media change		  FIXME: faking offline
861 		/* ECC */
862 		{0x40, 		MEDIUM_ERROR, 0x11, 0x04}, 	// Uncorrectable ECC error      Unrecovered read error
863 		/* BBD - block marked bad */
864 		{0x80, 		MEDIUM_ERROR, 0x11, 0x04}, 	// Block marked bad		  Medium error, unrecovered read error
865 		{0xFF, 0xFF, 0xFF, 0xFF}, // END mark
866 	};
867 	static const unsigned char stat_table[][4] = {
868 		/* Must be first because BUSY means no other bits valid */
869 		{0x80, 		ABORTED_COMMAND, 0x47, 0x00},	// Busy, fake parity for now
870 		{0x20, 		HARDWARE_ERROR,  0x00, 0x00}, 	// Device fault
871 		{0x08, 		ABORTED_COMMAND, 0x47, 0x00},	// Timed out in xfer, fake parity for now
872 		{0x04, 		RECOVERED_ERROR, 0x11, 0x00},	// Recovered ECC error	  Medium error, recovered
873 		{0xFF, 0xFF, 0xFF, 0xFF}, // END mark
874 	};
875 
876 	/*
877 	 *	Is this an error we can process/parse
878 	 */
879 	if (drv_stat & ATA_BUSY) {
880 		drv_err = 0;	/* Ignore the err bits, they're invalid */
881 	}
882 
883 	if (drv_err) {
884 		/* Look for drv_err */
885 		for (i = 0; sense_table[i][0] != 0xFF; i++) {
886 			/* Look for best matches first */
887 			if ((sense_table[i][0] & drv_err) ==
888 			    sense_table[i][0]) {
889 				*sk = sense_table[i][1];
890 				*asc = sense_table[i][2];
891 				*ascq = sense_table[i][3];
892 				goto translate_done;
893 			}
894 		}
895 		/* No immediate match */
896 		if (verbose)
897 			printk(KERN_WARNING "ata%u: no sense translation for "
898 			       "error 0x%02x\n", id, drv_err);
899 	}
900 
901 	/* Fall back to interpreting status bits */
902 	for (i = 0; stat_table[i][0] != 0xFF; i++) {
903 		if (stat_table[i][0] & drv_stat) {
904 			*sk = stat_table[i][1];
905 			*asc = stat_table[i][2];
906 			*ascq = stat_table[i][3];
907 			goto translate_done;
908 		}
909 	}
910 	/* No error?  Undecoded? */
911 	if (verbose)
912 		printk(KERN_WARNING "ata%u: no sense translation for "
913 		       "status: 0x%02x\n", id, drv_stat);
914 
915 	/* We need a sensible error return here, which is tricky, and one
916 	   that won't cause people to do things like return a disk wrongly */
917 	*sk = ABORTED_COMMAND;
918 	*asc = 0x00;
919 	*ascq = 0x00;
920 
921  translate_done:
922 	if (verbose)
923 		printk(KERN_ERR "ata%u: translated ATA stat/err 0x%02x/%02x "
924 		       "to SCSI SK/ASC/ASCQ 0x%x/%02x/%02x\n",
925 		       id, drv_stat, drv_err, *sk, *asc, *ascq);
926 	return;
927 }
928 
929 /*
930  *	ata_gen_passthru_sense - Generate check condition sense block.
931  *	@qc: Command that completed.
932  *
933  *	This function is specific to the ATA descriptor format sense
934  *	block specified for the ATA pass through commands.  Regardless
935  *	of whether the command errored or not, return a sense
936  *	block. Copy all controller registers into the sense
937  *	block. Clear sense key, ASC & ASCQ if there is no error.
938  *
939  *	LOCKING:
940  *	None.
941  */
942 static void ata_gen_passthru_sense(struct ata_queued_cmd *qc)
943 {
944 	struct scsi_cmnd *cmd = qc->scsicmd;
945 	struct ata_taskfile *tf = &qc->result_tf;
946 	unsigned char *sb = cmd->sense_buffer;
947 	unsigned char *desc = sb + 8;
948 	int verbose = qc->ap->ops->error_handler == NULL;
949 
950 	memset(sb, 0, SCSI_SENSE_BUFFERSIZE);
951 
952 	cmd->result = (DRIVER_SENSE << 24) | SAM_STAT_CHECK_CONDITION;
953 
954 	/*
955 	 * Use ata_to_sense_error() to map status register bits
956 	 * onto sense key, asc & ascq.
957 	 */
958 	if (qc->err_mask ||
959 	    tf->command & (ATA_BUSY | ATA_DF | ATA_ERR | ATA_DRQ)) {
960 		ata_to_sense_error(qc->ap->print_id, tf->command, tf->feature,
961 				   &sb[1], &sb[2], &sb[3], verbose);
962 		sb[1] &= 0x0f;
963 	}
964 
965 	/*
966 	 * Sense data is current and format is descriptor.
967 	 */
968 	sb[0] = 0x72;
969 
970 	desc[0] = 0x09;
971 
972 	/* set length of additional sense data */
973 	sb[7] = 14;
974 	desc[1] = 12;
975 
976 	/*
977 	 * Copy registers into sense buffer.
978 	 */
979 	desc[2] = 0x00;
980 	desc[3] = tf->feature;	/* == error reg */
981 	desc[5] = tf->nsect;
982 	desc[7] = tf->lbal;
983 	desc[9] = tf->lbam;
984 	desc[11] = tf->lbah;
985 	desc[12] = tf->device;
986 	desc[13] = tf->command; /* == status reg */
987 
988 	/*
989 	 * Fill in Extend bit, and the high order bytes
990 	 * if applicable.
991 	 */
992 	if (tf->flags & ATA_TFLAG_LBA48) {
993 		desc[2] |= 0x01;
994 		desc[4] = tf->hob_nsect;
995 		desc[6] = tf->hob_lbal;
996 		desc[8] = tf->hob_lbam;
997 		desc[10] = tf->hob_lbah;
998 	}
999 }
1000 
1001 /**
1002  *	ata_gen_ata_sense - generate a SCSI fixed sense block
1003  *	@qc: Command that we are erroring out
1004  *
1005  *	Generate sense block for a failed ATA command @qc.  Descriptor
1006  *	format is used to accomodate LBA48 block address.
1007  *
1008  *	LOCKING:
1009  *	None.
1010  */
1011 static void ata_gen_ata_sense(struct ata_queued_cmd *qc)
1012 {
1013 	struct ata_device *dev = qc->dev;
1014 	struct scsi_cmnd *cmd = qc->scsicmd;
1015 	struct ata_taskfile *tf = &qc->result_tf;
1016 	unsigned char *sb = cmd->sense_buffer;
1017 	unsigned char *desc = sb + 8;
1018 	int verbose = qc->ap->ops->error_handler == NULL;
1019 	u64 block;
1020 
1021 	memset(sb, 0, SCSI_SENSE_BUFFERSIZE);
1022 
1023 	cmd->result = (DRIVER_SENSE << 24) | SAM_STAT_CHECK_CONDITION;
1024 
1025 	/* sense data is current and format is descriptor */
1026 	sb[0] = 0x72;
1027 
1028 	/* Use ata_to_sense_error() to map status register bits
1029 	 * onto sense key, asc & ascq.
1030 	 */
1031 	if (qc->err_mask ||
1032 	    tf->command & (ATA_BUSY | ATA_DF | ATA_ERR | ATA_DRQ)) {
1033 		ata_to_sense_error(qc->ap->print_id, tf->command, tf->feature,
1034 				   &sb[1], &sb[2], &sb[3], verbose);
1035 		sb[1] &= 0x0f;
1036 	}
1037 
1038 	block = ata_tf_read_block(&qc->result_tf, dev);
1039 
1040 	/* information sense data descriptor */
1041 	sb[7] = 12;
1042 	desc[0] = 0x00;
1043 	desc[1] = 10;
1044 
1045 	desc[2] |= 0x80;	/* valid */
1046 	desc[6] = block >> 40;
1047 	desc[7] = block >> 32;
1048 	desc[8] = block >> 24;
1049 	desc[9] = block >> 16;
1050 	desc[10] = block >> 8;
1051 	desc[11] = block;
1052 }
1053 
1054 static void ata_scsi_sdev_config(struct scsi_device *sdev)
1055 {
1056 	sdev->use_10_for_rw = 1;
1057 	sdev->use_10_for_ms = 1;
1058 
1059 	/* Schedule policy is determined by ->qc_defer() callback and
1060 	 * it needs to see every deferred qc.  Set dev_blocked to 1 to
1061 	 * prevent SCSI midlayer from automatically deferring
1062 	 * requests.
1063 	 */
1064 	sdev->max_device_blocked = 1;
1065 }
1066 
1067 /**
1068  *	atapi_drain_needed - Check whether data transfer may overflow
1069  *	@rq: request to be checked
1070  *
1071  *	ATAPI commands which transfer variable length data to host
1072  *	might overflow due to application error or hardare bug.  This
1073  *	function checks whether overflow should be drained and ignored
1074  *	for @request.
1075  *
1076  *	LOCKING:
1077  *	None.
1078  *
1079  *	RETURNS:
1080  *	1 if ; otherwise, 0.
1081  */
1082 static int atapi_drain_needed(struct request *rq)
1083 {
1084 	if (likely(!blk_pc_request(rq)))
1085 		return 0;
1086 
1087 	if (!blk_rq_bytes(rq) || (rq->cmd_flags & REQ_RW))
1088 		return 0;
1089 
1090 	return atapi_cmd_type(rq->cmd[0]) == ATAPI_MISC;
1091 }
1092 
1093 static int ata_scsi_dev_config(struct scsi_device *sdev,
1094 			       struct ata_device *dev)
1095 {
1096 	if (!ata_id_has_unload(dev->id))
1097 		dev->flags |= ATA_DFLAG_NO_UNLOAD;
1098 
1099 	/* configure max sectors */
1100 	blk_queue_max_sectors(sdev->request_queue, dev->max_sectors);
1101 
1102 	if (dev->class == ATA_DEV_ATAPI) {
1103 		struct request_queue *q = sdev->request_queue;
1104 		void *buf;
1105 
1106 		/* set the min alignment and padding */
1107 		blk_queue_update_dma_alignment(sdev->request_queue,
1108 					       ATA_DMA_PAD_SZ - 1);
1109 		blk_queue_update_dma_pad(sdev->request_queue,
1110 					 ATA_DMA_PAD_SZ - 1);
1111 
1112 		/* configure draining */
1113 		buf = kmalloc(ATAPI_MAX_DRAIN, q->bounce_gfp | GFP_KERNEL);
1114 		if (!buf) {
1115 			ata_dev_printk(dev, KERN_ERR,
1116 				       "drain buffer allocation failed\n");
1117 			return -ENOMEM;
1118 		}
1119 
1120 		blk_queue_dma_drain(q, atapi_drain_needed, buf, ATAPI_MAX_DRAIN);
1121 	} else {
1122 		/* ATA devices must be sector aligned */
1123 		blk_queue_update_dma_alignment(sdev->request_queue,
1124 					       ATA_SECT_SIZE - 1);
1125 		sdev->manage_start_stop = 1;
1126 	}
1127 
1128 	if (dev->flags & ATA_DFLAG_AN)
1129 		set_bit(SDEV_EVT_MEDIA_CHANGE, sdev->supported_events);
1130 
1131 	if (dev->flags & ATA_DFLAG_NCQ) {
1132 		int depth;
1133 
1134 		depth = min(sdev->host->can_queue, ata_id_queue_depth(dev->id));
1135 		depth = min(ATA_MAX_QUEUE - 1, depth);
1136 		scsi_adjust_queue_depth(sdev, MSG_SIMPLE_TAG, depth);
1137 	}
1138 
1139 	return 0;
1140 }
1141 
1142 /**
1143  *	ata_scsi_slave_config - Set SCSI device attributes
1144  *	@sdev: SCSI device to examine
1145  *
1146  *	This is called before we actually start reading
1147  *	and writing to the device, to configure certain
1148  *	SCSI mid-layer behaviors.
1149  *
1150  *	LOCKING:
1151  *	Defined by SCSI layer.  We don't really care.
1152  */
1153 
1154 int ata_scsi_slave_config(struct scsi_device *sdev)
1155 {
1156 	struct ata_port *ap = ata_shost_to_port(sdev->host);
1157 	struct ata_device *dev = __ata_scsi_find_dev(ap, sdev);
1158 	int rc = 0;
1159 
1160 	ata_scsi_sdev_config(sdev);
1161 
1162 	if (dev)
1163 		rc = ata_scsi_dev_config(sdev, dev);
1164 
1165 	return rc;
1166 }
1167 
1168 /**
1169  *	ata_scsi_slave_destroy - SCSI device is about to be destroyed
1170  *	@sdev: SCSI device to be destroyed
1171  *
1172  *	@sdev is about to be destroyed for hot/warm unplugging.  If
1173  *	this unplugging was initiated by libata as indicated by NULL
1174  *	dev->sdev, this function doesn't have to do anything.
1175  *	Otherwise, SCSI layer initiated warm-unplug is in progress.
1176  *	Clear dev->sdev, schedule the device for ATA detach and invoke
1177  *	EH.
1178  *
1179  *	LOCKING:
1180  *	Defined by SCSI layer.  We don't really care.
1181  */
1182 void ata_scsi_slave_destroy(struct scsi_device *sdev)
1183 {
1184 	struct ata_port *ap = ata_shost_to_port(sdev->host);
1185 	struct request_queue *q = sdev->request_queue;
1186 	unsigned long flags;
1187 	struct ata_device *dev;
1188 
1189 	if (!ap->ops->error_handler)
1190 		return;
1191 
1192 	spin_lock_irqsave(ap->lock, flags);
1193 	dev = __ata_scsi_find_dev(ap, sdev);
1194 	if (dev && dev->sdev) {
1195 		/* SCSI device already in CANCEL state, no need to offline it */
1196 		dev->sdev = NULL;
1197 		dev->flags |= ATA_DFLAG_DETACH;
1198 		ata_port_schedule_eh(ap);
1199 	}
1200 	spin_unlock_irqrestore(ap->lock, flags);
1201 
1202 	kfree(q->dma_drain_buffer);
1203 	q->dma_drain_buffer = NULL;
1204 	q->dma_drain_size = 0;
1205 }
1206 
1207 /**
1208  *	ata_scsi_change_queue_depth - SCSI callback for queue depth config
1209  *	@sdev: SCSI device to configure queue depth for
1210  *	@queue_depth: new queue depth
1211  *	@reason: calling context
1212  *
1213  *	This is libata standard hostt->change_queue_depth callback.
1214  *	SCSI will call into this callback when user tries to set queue
1215  *	depth via sysfs.
1216  *
1217  *	LOCKING:
1218  *	SCSI layer (we don't care)
1219  *
1220  *	RETURNS:
1221  *	Newly configured queue depth.
1222  */
1223 int ata_scsi_change_queue_depth(struct scsi_device *sdev, int queue_depth,
1224 				int reason)
1225 {
1226 	struct ata_port *ap = ata_shost_to_port(sdev->host);
1227 	struct ata_device *dev;
1228 	unsigned long flags;
1229 
1230 	if (reason != SCSI_QDEPTH_DEFAULT)
1231 		return -EOPNOTSUPP;
1232 
1233 	if (queue_depth < 1 || queue_depth == sdev->queue_depth)
1234 		return sdev->queue_depth;
1235 
1236 	dev = ata_scsi_find_dev(ap, sdev);
1237 	if (!dev || !ata_dev_enabled(dev))
1238 		return sdev->queue_depth;
1239 
1240 	/* NCQ enabled? */
1241 	spin_lock_irqsave(ap->lock, flags);
1242 	dev->flags &= ~ATA_DFLAG_NCQ_OFF;
1243 	if (queue_depth == 1 || !ata_ncq_enabled(dev)) {
1244 		dev->flags |= ATA_DFLAG_NCQ_OFF;
1245 		queue_depth = 1;
1246 	}
1247 	spin_unlock_irqrestore(ap->lock, flags);
1248 
1249 	/* limit and apply queue depth */
1250 	queue_depth = min(queue_depth, sdev->host->can_queue);
1251 	queue_depth = min(queue_depth, ata_id_queue_depth(dev->id));
1252 	queue_depth = min(queue_depth, ATA_MAX_QUEUE - 1);
1253 
1254 	if (sdev->queue_depth == queue_depth)
1255 		return -EINVAL;
1256 
1257 	scsi_adjust_queue_depth(sdev, MSG_SIMPLE_TAG, queue_depth);
1258 	return queue_depth;
1259 }
1260 
1261 /**
1262  *	ata_scsi_start_stop_xlat - Translate SCSI START STOP UNIT command
1263  *	@qc: Storage for translated ATA taskfile
1264  *
1265  *	Sets up an ATA taskfile to issue STANDBY (to stop) or READ VERIFY
1266  *	(to start). Perhaps these commands should be preceded by
1267  *	CHECK POWER MODE to see what power mode the device is already in.
1268  *	[See SAT revision 5 at www.t10.org]
1269  *
1270  *	LOCKING:
1271  *	spin_lock_irqsave(host lock)
1272  *
1273  *	RETURNS:
1274  *	Zero on success, non-zero on error.
1275  */
1276 static unsigned int ata_scsi_start_stop_xlat(struct ata_queued_cmd *qc)
1277 {
1278 	struct scsi_cmnd *scmd = qc->scsicmd;
1279 	struct ata_taskfile *tf = &qc->tf;
1280 	const u8 *cdb = scmd->cmnd;
1281 
1282 	if (scmd->cmd_len < 5)
1283 		goto invalid_fld;
1284 
1285 	tf->flags |= ATA_TFLAG_DEVICE | ATA_TFLAG_ISADDR;
1286 	tf->protocol = ATA_PROT_NODATA;
1287 	if (cdb[1] & 0x1) {
1288 		;	/* ignore IMMED bit, violates sat-r05 */
1289 	}
1290 	if (cdb[4] & 0x2)
1291 		goto invalid_fld;       /* LOEJ bit set not supported */
1292 	if (((cdb[4] >> 4) & 0xf) != 0)
1293 		goto invalid_fld;       /* power conditions not supported */
1294 
1295 	if (cdb[4] & 0x1) {
1296 		tf->nsect = 1;	/* 1 sector, lba=0 */
1297 
1298 		if (qc->dev->flags & ATA_DFLAG_LBA) {
1299 			tf->flags |= ATA_TFLAG_LBA;
1300 
1301 			tf->lbah = 0x0;
1302 			tf->lbam = 0x0;
1303 			tf->lbal = 0x0;
1304 			tf->device |= ATA_LBA;
1305 		} else {
1306 			/* CHS */
1307 			tf->lbal = 0x1; /* sect */
1308 			tf->lbam = 0x0; /* cyl low */
1309 			tf->lbah = 0x0; /* cyl high */
1310 		}
1311 
1312 		tf->command = ATA_CMD_VERIFY;	/* READ VERIFY */
1313 	} else {
1314 		/* Some odd clown BIOSen issue spindown on power off (ACPI S4
1315 		 * or S5) causing some drives to spin up and down again.
1316 		 */
1317 		if ((qc->ap->flags & ATA_FLAG_NO_POWEROFF_SPINDOWN) &&
1318 		    system_state == SYSTEM_POWER_OFF)
1319 			goto skip;
1320 
1321 		if ((qc->ap->flags & ATA_FLAG_NO_HIBERNATE_SPINDOWN) &&
1322 		     system_entering_hibernation())
1323 			goto skip;
1324 
1325 		/* Issue ATA STANDBY IMMEDIATE command */
1326 		tf->command = ATA_CMD_STANDBYNOW1;
1327 	}
1328 
1329 	/*
1330 	 * Standby and Idle condition timers could be implemented but that
1331 	 * would require libata to implement the Power condition mode page
1332 	 * and allow the user to change it. Changing mode pages requires
1333 	 * MODE SELECT to be implemented.
1334 	 */
1335 
1336 	return 0;
1337 
1338  invalid_fld:
1339 	ata_scsi_set_sense(scmd, ILLEGAL_REQUEST, 0x24, 0x0);
1340 	/* "Invalid field in cbd" */
1341 	return 1;
1342  skip:
1343 	scmd->result = SAM_STAT_GOOD;
1344 	return 1;
1345 }
1346 
1347 
1348 /**
1349  *	ata_scsi_flush_xlat - Translate SCSI SYNCHRONIZE CACHE command
1350  *	@qc: Storage for translated ATA taskfile
1351  *
1352  *	Sets up an ATA taskfile to issue FLUSH CACHE or
1353  *	FLUSH CACHE EXT.
1354  *
1355  *	LOCKING:
1356  *	spin_lock_irqsave(host lock)
1357  *
1358  *	RETURNS:
1359  *	Zero on success, non-zero on error.
1360  */
1361 static unsigned int ata_scsi_flush_xlat(struct ata_queued_cmd *qc)
1362 {
1363 	struct ata_taskfile *tf = &qc->tf;
1364 
1365 	tf->flags |= ATA_TFLAG_DEVICE;
1366 	tf->protocol = ATA_PROT_NODATA;
1367 
1368 	if (qc->dev->flags & ATA_DFLAG_FLUSH_EXT)
1369 		tf->command = ATA_CMD_FLUSH_EXT;
1370 	else
1371 		tf->command = ATA_CMD_FLUSH;
1372 
1373 	/* flush is critical for IO integrity, consider it an IO command */
1374 	qc->flags |= ATA_QCFLAG_IO;
1375 
1376 	return 0;
1377 }
1378 
1379 /**
1380  *	scsi_6_lba_len - Get LBA and transfer length
1381  *	@cdb: SCSI command to translate
1382  *
1383  *	Calculate LBA and transfer length for 6-byte commands.
1384  *
1385  *	RETURNS:
1386  *	@plba: the LBA
1387  *	@plen: the transfer length
1388  */
1389 static void scsi_6_lba_len(const u8 *cdb, u64 *plba, u32 *plen)
1390 {
1391 	u64 lba = 0;
1392 	u32 len;
1393 
1394 	VPRINTK("six-byte command\n");
1395 
1396 	lba |= ((u64)(cdb[1] & 0x1f)) << 16;
1397 	lba |= ((u64)cdb[2]) << 8;
1398 	lba |= ((u64)cdb[3]);
1399 
1400 	len = cdb[4];
1401 
1402 	*plba = lba;
1403 	*plen = len;
1404 }
1405 
1406 /**
1407  *	scsi_10_lba_len - Get LBA and transfer length
1408  *	@cdb: SCSI command to translate
1409  *
1410  *	Calculate LBA and transfer length for 10-byte commands.
1411  *
1412  *	RETURNS:
1413  *	@plba: the LBA
1414  *	@plen: the transfer length
1415  */
1416 static void scsi_10_lba_len(const u8 *cdb, u64 *plba, u32 *plen)
1417 {
1418 	u64 lba = 0;
1419 	u32 len = 0;
1420 
1421 	VPRINTK("ten-byte command\n");
1422 
1423 	lba |= ((u64)cdb[2]) << 24;
1424 	lba |= ((u64)cdb[3]) << 16;
1425 	lba |= ((u64)cdb[4]) << 8;
1426 	lba |= ((u64)cdb[5]);
1427 
1428 	len |= ((u32)cdb[7]) << 8;
1429 	len |= ((u32)cdb[8]);
1430 
1431 	*plba = lba;
1432 	*plen = len;
1433 }
1434 
1435 /**
1436  *	scsi_16_lba_len - Get LBA and transfer length
1437  *	@cdb: SCSI command to translate
1438  *
1439  *	Calculate LBA and transfer length for 16-byte commands.
1440  *
1441  *	RETURNS:
1442  *	@plba: the LBA
1443  *	@plen: the transfer length
1444  */
1445 static void scsi_16_lba_len(const u8 *cdb, u64 *plba, u32 *plen)
1446 {
1447 	u64 lba = 0;
1448 	u32 len = 0;
1449 
1450 	VPRINTK("sixteen-byte command\n");
1451 
1452 	lba |= ((u64)cdb[2]) << 56;
1453 	lba |= ((u64)cdb[3]) << 48;
1454 	lba |= ((u64)cdb[4]) << 40;
1455 	lba |= ((u64)cdb[5]) << 32;
1456 	lba |= ((u64)cdb[6]) << 24;
1457 	lba |= ((u64)cdb[7]) << 16;
1458 	lba |= ((u64)cdb[8]) << 8;
1459 	lba |= ((u64)cdb[9]);
1460 
1461 	len |= ((u32)cdb[10]) << 24;
1462 	len |= ((u32)cdb[11]) << 16;
1463 	len |= ((u32)cdb[12]) << 8;
1464 	len |= ((u32)cdb[13]);
1465 
1466 	*plba = lba;
1467 	*plen = len;
1468 }
1469 
1470 /**
1471  *	ata_scsi_verify_xlat - Translate SCSI VERIFY command into an ATA one
1472  *	@qc: Storage for translated ATA taskfile
1473  *
1474  *	Converts SCSI VERIFY command to an ATA READ VERIFY command.
1475  *
1476  *	LOCKING:
1477  *	spin_lock_irqsave(host lock)
1478  *
1479  *	RETURNS:
1480  *	Zero on success, non-zero on error.
1481  */
1482 static unsigned int ata_scsi_verify_xlat(struct ata_queued_cmd *qc)
1483 {
1484 	struct scsi_cmnd *scmd = qc->scsicmd;
1485 	struct ata_taskfile *tf = &qc->tf;
1486 	struct ata_device *dev = qc->dev;
1487 	u64 dev_sectors = qc->dev->n_sectors;
1488 	const u8 *cdb = scmd->cmnd;
1489 	u64 block;
1490 	u32 n_block;
1491 
1492 	tf->flags |= ATA_TFLAG_ISADDR | ATA_TFLAG_DEVICE;
1493 	tf->protocol = ATA_PROT_NODATA;
1494 
1495 	if (cdb[0] == VERIFY) {
1496 		if (scmd->cmd_len < 10)
1497 			goto invalid_fld;
1498 		scsi_10_lba_len(cdb, &block, &n_block);
1499 	} else if (cdb[0] == VERIFY_16) {
1500 		if (scmd->cmd_len < 16)
1501 			goto invalid_fld;
1502 		scsi_16_lba_len(cdb, &block, &n_block);
1503 	} else
1504 		goto invalid_fld;
1505 
1506 	if (!n_block)
1507 		goto nothing_to_do;
1508 	if (block >= dev_sectors)
1509 		goto out_of_range;
1510 	if ((block + n_block) > dev_sectors)
1511 		goto out_of_range;
1512 
1513 	if (dev->flags & ATA_DFLAG_LBA) {
1514 		tf->flags |= ATA_TFLAG_LBA;
1515 
1516 		if (lba_28_ok(block, n_block)) {
1517 			/* use LBA28 */
1518 			tf->command = ATA_CMD_VERIFY;
1519 			tf->device |= (block >> 24) & 0xf;
1520 		} else if (lba_48_ok(block, n_block)) {
1521 			if (!(dev->flags & ATA_DFLAG_LBA48))
1522 				goto out_of_range;
1523 
1524 			/* use LBA48 */
1525 			tf->flags |= ATA_TFLAG_LBA48;
1526 			tf->command = ATA_CMD_VERIFY_EXT;
1527 
1528 			tf->hob_nsect = (n_block >> 8) & 0xff;
1529 
1530 			tf->hob_lbah = (block >> 40) & 0xff;
1531 			tf->hob_lbam = (block >> 32) & 0xff;
1532 			tf->hob_lbal = (block >> 24) & 0xff;
1533 		} else
1534 			/* request too large even for LBA48 */
1535 			goto out_of_range;
1536 
1537 		tf->nsect = n_block & 0xff;
1538 
1539 		tf->lbah = (block >> 16) & 0xff;
1540 		tf->lbam = (block >> 8) & 0xff;
1541 		tf->lbal = block & 0xff;
1542 
1543 		tf->device |= ATA_LBA;
1544 	} else {
1545 		/* CHS */
1546 		u32 sect, head, cyl, track;
1547 
1548 		if (!lba_28_ok(block, n_block))
1549 			goto out_of_range;
1550 
1551 		/* Convert LBA to CHS */
1552 		track = (u32)block / dev->sectors;
1553 		cyl   = track / dev->heads;
1554 		head  = track % dev->heads;
1555 		sect  = (u32)block % dev->sectors + 1;
1556 
1557 		DPRINTK("block %u track %u cyl %u head %u sect %u\n",
1558 			(u32)block, track, cyl, head, sect);
1559 
1560 		/* Check whether the converted CHS can fit.
1561 		   Cylinder: 0-65535
1562 		   Head: 0-15
1563 		   Sector: 1-255*/
1564 		if ((cyl >> 16) || (head >> 4) || (sect >> 8) || (!sect))
1565 			goto out_of_range;
1566 
1567 		tf->command = ATA_CMD_VERIFY;
1568 		tf->nsect = n_block & 0xff; /* Sector count 0 means 256 sectors */
1569 		tf->lbal = sect;
1570 		tf->lbam = cyl;
1571 		tf->lbah = cyl >> 8;
1572 		tf->device |= head;
1573 	}
1574 
1575 	return 0;
1576 
1577 invalid_fld:
1578 	ata_scsi_set_sense(scmd, ILLEGAL_REQUEST, 0x24, 0x0);
1579 	/* "Invalid field in cbd" */
1580 	return 1;
1581 
1582 out_of_range:
1583 	ata_scsi_set_sense(scmd, ILLEGAL_REQUEST, 0x21, 0x0);
1584 	/* "Logical Block Address out of range" */
1585 	return 1;
1586 
1587 nothing_to_do:
1588 	scmd->result = SAM_STAT_GOOD;
1589 	return 1;
1590 }
1591 
1592 /**
1593  *	ata_scsi_rw_xlat - Translate SCSI r/w command into an ATA one
1594  *	@qc: Storage for translated ATA taskfile
1595  *
1596  *	Converts any of six SCSI read/write commands into the
1597  *	ATA counterpart, including starting sector (LBA),
1598  *	sector count, and taking into account the device's LBA48
1599  *	support.
1600  *
1601  *	Commands %READ_6, %READ_10, %READ_16, %WRITE_6, %WRITE_10, and
1602  *	%WRITE_16 are currently supported.
1603  *
1604  *	LOCKING:
1605  *	spin_lock_irqsave(host lock)
1606  *
1607  *	RETURNS:
1608  *	Zero on success, non-zero on error.
1609  */
1610 static unsigned int ata_scsi_rw_xlat(struct ata_queued_cmd *qc)
1611 {
1612 	struct scsi_cmnd *scmd = qc->scsicmd;
1613 	const u8 *cdb = scmd->cmnd;
1614 	unsigned int tf_flags = 0;
1615 	u64 block;
1616 	u32 n_block;
1617 	int rc;
1618 
1619 	if (cdb[0] == WRITE_10 || cdb[0] == WRITE_6 || cdb[0] == WRITE_16)
1620 		tf_flags |= ATA_TFLAG_WRITE;
1621 
1622 	/* Calculate the SCSI LBA, transfer length and FUA. */
1623 	switch (cdb[0]) {
1624 	case READ_10:
1625 	case WRITE_10:
1626 		if (unlikely(scmd->cmd_len < 10))
1627 			goto invalid_fld;
1628 		scsi_10_lba_len(cdb, &block, &n_block);
1629 		if (unlikely(cdb[1] & (1 << 3)))
1630 			tf_flags |= ATA_TFLAG_FUA;
1631 		break;
1632 	case READ_6:
1633 	case WRITE_6:
1634 		if (unlikely(scmd->cmd_len < 6))
1635 			goto invalid_fld;
1636 		scsi_6_lba_len(cdb, &block, &n_block);
1637 
1638 		/* for 6-byte r/w commands, transfer length 0
1639 		 * means 256 blocks of data, not 0 block.
1640 		 */
1641 		if (!n_block)
1642 			n_block = 256;
1643 		break;
1644 	case READ_16:
1645 	case WRITE_16:
1646 		if (unlikely(scmd->cmd_len < 16))
1647 			goto invalid_fld;
1648 		scsi_16_lba_len(cdb, &block, &n_block);
1649 		if (unlikely(cdb[1] & (1 << 3)))
1650 			tf_flags |= ATA_TFLAG_FUA;
1651 		break;
1652 	default:
1653 		DPRINTK("no-byte command\n");
1654 		goto invalid_fld;
1655 	}
1656 
1657 	/* Check and compose ATA command */
1658 	if (!n_block)
1659 		/* For 10-byte and 16-byte SCSI R/W commands, transfer
1660 		 * length 0 means transfer 0 block of data.
1661 		 * However, for ATA R/W commands, sector count 0 means
1662 		 * 256 or 65536 sectors, not 0 sectors as in SCSI.
1663 		 *
1664 		 * WARNING: one or two older ATA drives treat 0 as 0...
1665 		 */
1666 		goto nothing_to_do;
1667 
1668 	qc->flags |= ATA_QCFLAG_IO;
1669 	qc->nbytes = n_block * ATA_SECT_SIZE;
1670 
1671 	rc = ata_build_rw_tf(&qc->tf, qc->dev, block, n_block, tf_flags,
1672 			     qc->tag);
1673 	if (likely(rc == 0))
1674 		return 0;
1675 
1676 	if (rc == -ERANGE)
1677 		goto out_of_range;
1678 	/* treat all other errors as -EINVAL, fall through */
1679 invalid_fld:
1680 	ata_scsi_set_sense(scmd, ILLEGAL_REQUEST, 0x24, 0x0);
1681 	/* "Invalid field in cbd" */
1682 	return 1;
1683 
1684 out_of_range:
1685 	ata_scsi_set_sense(scmd, ILLEGAL_REQUEST, 0x21, 0x0);
1686 	/* "Logical Block Address out of range" */
1687 	return 1;
1688 
1689 nothing_to_do:
1690 	scmd->result = SAM_STAT_GOOD;
1691 	return 1;
1692 }
1693 
1694 static void ata_scsi_qc_complete(struct ata_queued_cmd *qc)
1695 {
1696 	struct ata_port *ap = qc->ap;
1697 	struct scsi_cmnd *cmd = qc->scsicmd;
1698 	u8 *cdb = cmd->cmnd;
1699 	int need_sense = (qc->err_mask != 0);
1700 
1701 	/* For ATA pass thru (SAT) commands, generate a sense block if
1702 	 * user mandated it or if there's an error.  Note that if we
1703 	 * generate because the user forced us to, a check condition
1704 	 * is generated and the ATA register values are returned
1705 	 * whether the command completed successfully or not. If there
1706 	 * was no error, SK, ASC and ASCQ will all be zero.
1707 	 */
1708 	if (((cdb[0] == ATA_16) || (cdb[0] == ATA_12)) &&
1709 	    ((cdb[2] & 0x20) || need_sense)) {
1710 		ata_gen_passthru_sense(qc);
1711 	} else {
1712 		if (!need_sense) {
1713 			cmd->result = SAM_STAT_GOOD;
1714 		} else {
1715 			/* TODO: decide which descriptor format to use
1716 			 * for 48b LBA devices and call that here
1717 			 * instead of the fixed desc, which is only
1718 			 * good for smaller LBA (and maybe CHS?)
1719 			 * devices.
1720 			 */
1721 			ata_gen_ata_sense(qc);
1722 		}
1723 	}
1724 
1725 	if (need_sense && !ap->ops->error_handler)
1726 		ata_dump_status(ap->print_id, &qc->result_tf);
1727 
1728 	qc->scsidone(cmd);
1729 
1730 	ata_qc_free(qc);
1731 }
1732 
1733 /**
1734  *	ata_scsi_translate - Translate then issue SCSI command to ATA device
1735  *	@dev: ATA device to which the command is addressed
1736  *	@cmd: SCSI command to execute
1737  *	@done: SCSI command completion function
1738  *	@xlat_func: Actor which translates @cmd to an ATA taskfile
1739  *
1740  *	Our ->queuecommand() function has decided that the SCSI
1741  *	command issued can be directly translated into an ATA
1742  *	command, rather than handled internally.
1743  *
1744  *	This function sets up an ata_queued_cmd structure for the
1745  *	SCSI command, and sends that ata_queued_cmd to the hardware.
1746  *
1747  *	The xlat_func argument (actor) returns 0 if ready to execute
1748  *	ATA command, else 1 to finish translation. If 1 is returned
1749  *	then cmd->result (and possibly cmd->sense_buffer) are assumed
1750  *	to be set reflecting an error condition or clean (early)
1751  *	termination.
1752  *
1753  *	LOCKING:
1754  *	spin_lock_irqsave(host lock)
1755  *
1756  *	RETURNS:
1757  *	0 on success, SCSI_ML_QUEUE_DEVICE_BUSY if the command
1758  *	needs to be deferred.
1759  */
1760 static int ata_scsi_translate(struct ata_device *dev, struct scsi_cmnd *cmd,
1761 			      void (*done)(struct scsi_cmnd *),
1762 			      ata_xlat_func_t xlat_func)
1763 {
1764 	struct ata_port *ap = dev->link->ap;
1765 	struct ata_queued_cmd *qc;
1766 	int rc;
1767 
1768 	VPRINTK("ENTER\n");
1769 
1770 	qc = ata_scsi_qc_new(dev, cmd, done);
1771 	if (!qc)
1772 		goto err_mem;
1773 
1774 	/* data is present; dma-map it */
1775 	if (cmd->sc_data_direction == DMA_FROM_DEVICE ||
1776 	    cmd->sc_data_direction == DMA_TO_DEVICE) {
1777 		if (unlikely(scsi_bufflen(cmd) < 1)) {
1778 			ata_dev_printk(dev, KERN_WARNING,
1779 				       "WARNING: zero len r/w req\n");
1780 			goto err_did;
1781 		}
1782 
1783 		ata_sg_init(qc, scsi_sglist(cmd), scsi_sg_count(cmd));
1784 
1785 		qc->dma_dir = cmd->sc_data_direction;
1786 	}
1787 
1788 	qc->complete_fn = ata_scsi_qc_complete;
1789 
1790 	if (xlat_func(qc))
1791 		goto early_finish;
1792 
1793 	if (ap->ops->qc_defer) {
1794 		if ((rc = ap->ops->qc_defer(qc)))
1795 			goto defer;
1796 	}
1797 
1798 	/* select device, send command to hardware */
1799 	ata_qc_issue(qc);
1800 
1801 	VPRINTK("EXIT\n");
1802 	return 0;
1803 
1804 early_finish:
1805 	ata_qc_free(qc);
1806 	qc->scsidone(cmd);
1807 	DPRINTK("EXIT - early finish (good or error)\n");
1808 	return 0;
1809 
1810 err_did:
1811 	ata_qc_free(qc);
1812 	cmd->result = (DID_ERROR << 16);
1813 	qc->scsidone(cmd);
1814 err_mem:
1815 	DPRINTK("EXIT - internal\n");
1816 	return 0;
1817 
1818 defer:
1819 	ata_qc_free(qc);
1820 	DPRINTK("EXIT - defer\n");
1821 	if (rc == ATA_DEFER_LINK)
1822 		return SCSI_MLQUEUE_DEVICE_BUSY;
1823 	else
1824 		return SCSI_MLQUEUE_HOST_BUSY;
1825 }
1826 
1827 /**
1828  *	ata_scsi_rbuf_get - Map response buffer.
1829  *	@cmd: SCSI command containing buffer to be mapped.
1830  *	@flags: unsigned long variable to store irq enable status
1831  *	@copy_in: copy in from user buffer
1832  *
1833  *	Prepare buffer for simulated SCSI commands.
1834  *
1835  *	LOCKING:
1836  *	spin_lock_irqsave(ata_scsi_rbuf_lock) on success
1837  *
1838  *	RETURNS:
1839  *	Pointer to response buffer.
1840  */
1841 static void *ata_scsi_rbuf_get(struct scsi_cmnd *cmd, bool copy_in,
1842 			       unsigned long *flags)
1843 {
1844 	spin_lock_irqsave(&ata_scsi_rbuf_lock, *flags);
1845 
1846 	memset(ata_scsi_rbuf, 0, ATA_SCSI_RBUF_SIZE);
1847 	if (copy_in)
1848 		sg_copy_to_buffer(scsi_sglist(cmd), scsi_sg_count(cmd),
1849 				  ata_scsi_rbuf, ATA_SCSI_RBUF_SIZE);
1850 	return ata_scsi_rbuf;
1851 }
1852 
1853 /**
1854  *	ata_scsi_rbuf_put - Unmap response buffer.
1855  *	@cmd: SCSI command containing buffer to be unmapped.
1856  *	@copy_out: copy out result
1857  *	@flags: @flags passed to ata_scsi_rbuf_get()
1858  *
1859  *	Returns rbuf buffer.  The result is copied to @cmd's buffer if
1860  *	@copy_back is true.
1861  *
1862  *	LOCKING:
1863  *	Unlocks ata_scsi_rbuf_lock.
1864  */
1865 static inline void ata_scsi_rbuf_put(struct scsi_cmnd *cmd, bool copy_out,
1866 				     unsigned long *flags)
1867 {
1868 	if (copy_out)
1869 		sg_copy_from_buffer(scsi_sglist(cmd), scsi_sg_count(cmd),
1870 				    ata_scsi_rbuf, ATA_SCSI_RBUF_SIZE);
1871 	spin_unlock_irqrestore(&ata_scsi_rbuf_lock, *flags);
1872 }
1873 
1874 /**
1875  *	ata_scsi_rbuf_fill - wrapper for SCSI command simulators
1876  *	@args: device IDENTIFY data / SCSI command of interest.
1877  *	@actor: Callback hook for desired SCSI command simulator
1878  *
1879  *	Takes care of the hard work of simulating a SCSI command...
1880  *	Mapping the response buffer, calling the command's handler,
1881  *	and handling the handler's return value.  This return value
1882  *	indicates whether the handler wishes the SCSI command to be
1883  *	completed successfully (0), or not (in which case cmd->result
1884  *	and sense buffer are assumed to be set).
1885  *
1886  *	LOCKING:
1887  *	spin_lock_irqsave(host lock)
1888  */
1889 static void ata_scsi_rbuf_fill(struct ata_scsi_args *args,
1890 		unsigned int (*actor)(struct ata_scsi_args *args, u8 *rbuf))
1891 {
1892 	u8 *rbuf;
1893 	unsigned int rc;
1894 	struct scsi_cmnd *cmd = args->cmd;
1895 	unsigned long flags;
1896 
1897 	rbuf = ata_scsi_rbuf_get(cmd, false, &flags);
1898 	rc = actor(args, rbuf);
1899 	ata_scsi_rbuf_put(cmd, rc == 0, &flags);
1900 
1901 	if (rc == 0)
1902 		cmd->result = SAM_STAT_GOOD;
1903 	args->done(cmd);
1904 }
1905 
1906 /**
1907  *	ata_scsiop_inq_std - Simulate INQUIRY command
1908  *	@args: device IDENTIFY data / SCSI command of interest.
1909  *	@rbuf: Response buffer, to which simulated SCSI cmd output is sent.
1910  *
1911  *	Returns standard device identification data associated
1912  *	with non-VPD INQUIRY command output.
1913  *
1914  *	LOCKING:
1915  *	spin_lock_irqsave(host lock)
1916  */
1917 static unsigned int ata_scsiop_inq_std(struct ata_scsi_args *args, u8 *rbuf)
1918 {
1919 	const u8 versions[] = {
1920 		0x60,	/* SAM-3 (no version claimed) */
1921 
1922 		0x03,
1923 		0x20,	/* SBC-2 (no version claimed) */
1924 
1925 		0x02,
1926 		0x60	/* SPC-3 (no version claimed) */
1927 	};
1928 	u8 hdr[] = {
1929 		TYPE_DISK,
1930 		0,
1931 		0x5,	/* claim SPC-3 version compatibility */
1932 		2,
1933 		95 - 4
1934 	};
1935 
1936 	VPRINTK("ENTER\n");
1937 
1938 	/* set scsi removeable (RMB) bit per ata bit */
1939 	if (ata_id_removeable(args->id))
1940 		hdr[1] |= (1 << 7);
1941 
1942 	memcpy(rbuf, hdr, sizeof(hdr));
1943 	memcpy(&rbuf[8], "ATA     ", 8);
1944 	ata_id_string(args->id, &rbuf[16], ATA_ID_PROD, 16);
1945 	ata_id_string(args->id, &rbuf[32], ATA_ID_FW_REV, 4);
1946 
1947 	if (rbuf[32] == 0 || rbuf[32] == ' ')
1948 		memcpy(&rbuf[32], "n/a ", 4);
1949 
1950 	memcpy(rbuf + 59, versions, sizeof(versions));
1951 
1952 	return 0;
1953 }
1954 
1955 /**
1956  *	ata_scsiop_inq_00 - Simulate INQUIRY VPD page 0, list of pages
1957  *	@args: device IDENTIFY data / SCSI command of interest.
1958  *	@rbuf: Response buffer, to which simulated SCSI cmd output is sent.
1959  *
1960  *	Returns list of inquiry VPD pages available.
1961  *
1962  *	LOCKING:
1963  *	spin_lock_irqsave(host lock)
1964  */
1965 static unsigned int ata_scsiop_inq_00(struct ata_scsi_args *args, u8 *rbuf)
1966 {
1967 	const u8 pages[] = {
1968 		0x00,	/* page 0x00, this page */
1969 		0x80,	/* page 0x80, unit serial no page */
1970 		0x83,	/* page 0x83, device ident page */
1971 		0x89,	/* page 0x89, ata info page */
1972 		0xb0,	/* page 0xb0, block limits page */
1973 		0xb1,	/* page 0xb1, block device characteristics page */
1974 	};
1975 
1976 	rbuf[3] = sizeof(pages);	/* number of supported VPD pages */
1977 	memcpy(rbuf + 4, pages, sizeof(pages));
1978 	return 0;
1979 }
1980 
1981 /**
1982  *	ata_scsiop_inq_80 - Simulate INQUIRY VPD page 80, device serial number
1983  *	@args: device IDENTIFY data / SCSI command of interest.
1984  *	@rbuf: Response buffer, to which simulated SCSI cmd output is sent.
1985  *
1986  *	Returns ATA device serial number.
1987  *
1988  *	LOCKING:
1989  *	spin_lock_irqsave(host lock)
1990  */
1991 static unsigned int ata_scsiop_inq_80(struct ata_scsi_args *args, u8 *rbuf)
1992 {
1993 	const u8 hdr[] = {
1994 		0,
1995 		0x80,			/* this page code */
1996 		0,
1997 		ATA_ID_SERNO_LEN,	/* page len */
1998 	};
1999 
2000 	memcpy(rbuf, hdr, sizeof(hdr));
2001 	ata_id_string(args->id, (unsigned char *) &rbuf[4],
2002 		      ATA_ID_SERNO, ATA_ID_SERNO_LEN);
2003 	return 0;
2004 }
2005 
2006 /**
2007  *	ata_scsiop_inq_83 - Simulate INQUIRY VPD page 83, device identity
2008  *	@args: device IDENTIFY data / SCSI command of interest.
2009  *	@rbuf: Response buffer, to which simulated SCSI cmd output is sent.
2010  *
2011  *	Yields two logical unit device identification designators:
2012  *	 - vendor specific ASCII containing the ATA serial number
2013  *	 - SAT defined "t10 vendor id based" containing ASCII vendor
2014  *	   name ("ATA     "), model and serial numbers.
2015  *
2016  *	LOCKING:
2017  *	spin_lock_irqsave(host lock)
2018  */
2019 static unsigned int ata_scsiop_inq_83(struct ata_scsi_args *args, u8 *rbuf)
2020 {
2021 	const int sat_model_serial_desc_len = 68;
2022 	int num;
2023 
2024 	rbuf[1] = 0x83;			/* this page code */
2025 	num = 4;
2026 
2027 	/* piv=0, assoc=lu, code_set=ACSII, designator=vendor */
2028 	rbuf[num + 0] = 2;
2029 	rbuf[num + 3] = ATA_ID_SERNO_LEN;
2030 	num += 4;
2031 	ata_id_string(args->id, (unsigned char *) rbuf + num,
2032 		      ATA_ID_SERNO, ATA_ID_SERNO_LEN);
2033 	num += ATA_ID_SERNO_LEN;
2034 
2035 	/* SAT defined lu model and serial numbers descriptor */
2036 	/* piv=0, assoc=lu, code_set=ACSII, designator=t10 vendor id */
2037 	rbuf[num + 0] = 2;
2038 	rbuf[num + 1] = 1;
2039 	rbuf[num + 3] = sat_model_serial_desc_len;
2040 	num += 4;
2041 	memcpy(rbuf + num, "ATA     ", 8);
2042 	num += 8;
2043 	ata_id_string(args->id, (unsigned char *) rbuf + num, ATA_ID_PROD,
2044 		      ATA_ID_PROD_LEN);
2045 	num += ATA_ID_PROD_LEN;
2046 	ata_id_string(args->id, (unsigned char *) rbuf + num, ATA_ID_SERNO,
2047 		      ATA_ID_SERNO_LEN);
2048 	num += ATA_ID_SERNO_LEN;
2049 
2050 	rbuf[3] = num - 4;    /* page len (assume less than 256 bytes) */
2051 	return 0;
2052 }
2053 
2054 /**
2055  *	ata_scsiop_inq_89 - Simulate INQUIRY VPD page 89, ATA info
2056  *	@args: device IDENTIFY data / SCSI command of interest.
2057  *	@rbuf: Response buffer, to which simulated SCSI cmd output is sent.
2058  *
2059  *	Yields SAT-specified ATA VPD page.
2060  *
2061  *	LOCKING:
2062  *	spin_lock_irqsave(host lock)
2063  */
2064 static unsigned int ata_scsiop_inq_89(struct ata_scsi_args *args, u8 *rbuf)
2065 {
2066 	struct ata_taskfile tf;
2067 
2068 	memset(&tf, 0, sizeof(tf));
2069 
2070 	rbuf[1] = 0x89;			/* our page code */
2071 	rbuf[2] = (0x238 >> 8);		/* page size fixed at 238h */
2072 	rbuf[3] = (0x238 & 0xff);
2073 
2074 	memcpy(&rbuf[8], "linux   ", 8);
2075 	memcpy(&rbuf[16], "libata          ", 16);
2076 	memcpy(&rbuf[32], DRV_VERSION, 4);
2077 	ata_id_string(args->id, &rbuf[32], ATA_ID_FW_REV, 4);
2078 
2079 	/* we don't store the ATA device signature, so we fake it */
2080 
2081 	tf.command = ATA_DRDY;		/* really, this is Status reg */
2082 	tf.lbal = 0x1;
2083 	tf.nsect = 0x1;
2084 
2085 	ata_tf_to_fis(&tf, 0, 1, &rbuf[36]);	/* TODO: PMP? */
2086 	rbuf[36] = 0x34;		/* force D2H Reg FIS (34h) */
2087 
2088 	rbuf[56] = ATA_CMD_ID_ATA;
2089 
2090 	memcpy(&rbuf[60], &args->id[0], 512);
2091 	return 0;
2092 }
2093 
2094 static unsigned int ata_scsiop_inq_b0(struct ata_scsi_args *args, u8 *rbuf)
2095 {
2096 	u32 min_io_sectors;
2097 
2098 	rbuf[1] = 0xb0;
2099 	rbuf[3] = 0x3c;		/* required VPD size with unmap support */
2100 
2101 	/*
2102 	 * Optimal transfer length granularity.
2103 	 *
2104 	 * This is always one physical block, but for disks with a smaller
2105 	 * logical than physical sector size we need to figure out what the
2106 	 * latter is.
2107 	 */
2108 	if (ata_id_has_large_logical_sectors(args->id))
2109 		min_io_sectors = ata_id_logical_per_physical_sectors(args->id);
2110 	else
2111 		min_io_sectors = 1;
2112 	put_unaligned_be16(min_io_sectors, &rbuf[6]);
2113 
2114 	/*
2115 	 * Optimal unmap granularity.
2116 	 *
2117 	 * The ATA spec doesn't even know about a granularity or alignment
2118 	 * for the TRIM command.  We can leave away most of the unmap related
2119 	 * VPD page entries, but we have specifify a granularity to signal
2120 	 * that we support some form of unmap - in thise case via WRITE SAME
2121 	 * with the unmap bit set.
2122 	 */
2123 	if (ata_id_has_trim(args->id)) {
2124 		put_unaligned_be32(65535 * 512 / 8, &rbuf[20]);
2125 		put_unaligned_be32(1, &rbuf[28]);
2126 	}
2127 
2128 	return 0;
2129 }
2130 
2131 static unsigned int ata_scsiop_inq_b1(struct ata_scsi_args *args, u8 *rbuf)
2132 {
2133 	int form_factor = ata_id_form_factor(args->id);
2134 	int media_rotation_rate = ata_id_rotation_rate(args->id);
2135 
2136 	rbuf[1] = 0xb1;
2137 	rbuf[3] = 0x3c;
2138 	rbuf[4] = media_rotation_rate >> 8;
2139 	rbuf[5] = media_rotation_rate;
2140 	rbuf[7] = form_factor;
2141 
2142 	return 0;
2143 }
2144 
2145 /**
2146  *	ata_scsiop_noop - Command handler that simply returns success.
2147  *	@args: device IDENTIFY data / SCSI command of interest.
2148  *	@rbuf: Response buffer, to which simulated SCSI cmd output is sent.
2149  *
2150  *	No operation.  Simply returns success to caller, to indicate
2151  *	that the caller should successfully complete this SCSI command.
2152  *
2153  *	LOCKING:
2154  *	spin_lock_irqsave(host lock)
2155  */
2156 static unsigned int ata_scsiop_noop(struct ata_scsi_args *args, u8 *rbuf)
2157 {
2158 	VPRINTK("ENTER\n");
2159 	return 0;
2160 }
2161 
2162 /**
2163  *	ata_msense_caching - Simulate MODE SENSE caching info page
2164  *	@id: device IDENTIFY data
2165  *	@buf: output buffer
2166  *
2167  *	Generate a caching info page, which conditionally indicates
2168  *	write caching to the SCSI layer, depending on device
2169  *	capabilities.
2170  *
2171  *	LOCKING:
2172  *	None.
2173  */
2174 static unsigned int ata_msense_caching(u16 *id, u8 *buf)
2175 {
2176 	memcpy(buf, def_cache_mpage, sizeof(def_cache_mpage));
2177 	if (ata_id_wcache_enabled(id))
2178 		buf[2] |= (1 << 2);	/* write cache enable */
2179 	if (!ata_id_rahead_enabled(id))
2180 		buf[12] |= (1 << 5);	/* disable read ahead */
2181 	return sizeof(def_cache_mpage);
2182 }
2183 
2184 /**
2185  *	ata_msense_ctl_mode - Simulate MODE SENSE control mode page
2186  *	@buf: output buffer
2187  *
2188  *	Generate a generic MODE SENSE control mode page.
2189  *
2190  *	LOCKING:
2191  *	None.
2192  */
2193 static unsigned int ata_msense_ctl_mode(u8 *buf)
2194 {
2195 	memcpy(buf, def_control_mpage, sizeof(def_control_mpage));
2196 	return sizeof(def_control_mpage);
2197 }
2198 
2199 /**
2200  *	ata_msense_rw_recovery - Simulate MODE SENSE r/w error recovery page
2201  *	@buf: output buffer
2202  *
2203  *	Generate a generic MODE SENSE r/w error recovery page.
2204  *
2205  *	LOCKING:
2206  *	None.
2207  */
2208 static unsigned int ata_msense_rw_recovery(u8 *buf)
2209 {
2210 	memcpy(buf, def_rw_recovery_mpage, sizeof(def_rw_recovery_mpage));
2211 	return sizeof(def_rw_recovery_mpage);
2212 }
2213 
2214 /*
2215  * We can turn this into a real blacklist if it's needed, for now just
2216  * blacklist any Maxtor BANC1G10 revision firmware
2217  */
2218 static int ata_dev_supports_fua(u16 *id)
2219 {
2220 	unsigned char model[ATA_ID_PROD_LEN + 1], fw[ATA_ID_FW_REV_LEN + 1];
2221 
2222 	if (!libata_fua)
2223 		return 0;
2224 	if (!ata_id_has_fua(id))
2225 		return 0;
2226 
2227 	ata_id_c_string(id, model, ATA_ID_PROD, sizeof(model));
2228 	ata_id_c_string(id, fw, ATA_ID_FW_REV, sizeof(fw));
2229 
2230 	if (strcmp(model, "Maxtor"))
2231 		return 1;
2232 	if (strcmp(fw, "BANC1G10"))
2233 		return 1;
2234 
2235 	return 0; /* blacklisted */
2236 }
2237 
2238 /**
2239  *	ata_scsiop_mode_sense - Simulate MODE SENSE 6, 10 commands
2240  *	@args: device IDENTIFY data / SCSI command of interest.
2241  *	@rbuf: Response buffer, to which simulated SCSI cmd output is sent.
2242  *
2243  *	Simulate MODE SENSE commands. Assume this is invoked for direct
2244  *	access devices (e.g. disks) only. There should be no block
2245  *	descriptor for other device types.
2246  *
2247  *	LOCKING:
2248  *	spin_lock_irqsave(host lock)
2249  */
2250 static unsigned int ata_scsiop_mode_sense(struct ata_scsi_args *args, u8 *rbuf)
2251 {
2252 	struct ata_device *dev = args->dev;
2253 	u8 *scsicmd = args->cmd->cmnd, *p = rbuf;
2254 	const u8 sat_blk_desc[] = {
2255 		0, 0, 0, 0,	/* number of blocks: sat unspecified */
2256 		0,
2257 		0, 0x2, 0x0	/* block length: 512 bytes */
2258 	};
2259 	u8 pg, spg;
2260 	unsigned int ebd, page_control, six_byte;
2261 	u8 dpofua;
2262 
2263 	VPRINTK("ENTER\n");
2264 
2265 	six_byte = (scsicmd[0] == MODE_SENSE);
2266 	ebd = !(scsicmd[1] & 0x8);      /* dbd bit inverted == edb */
2267 	/*
2268 	 * LLBA bit in msense(10) ignored (compliant)
2269 	 */
2270 
2271 	page_control = scsicmd[2] >> 6;
2272 	switch (page_control) {
2273 	case 0: /* current */
2274 		break;  /* supported */
2275 	case 3: /* saved */
2276 		goto saving_not_supp;
2277 	case 1: /* changeable */
2278 	case 2: /* defaults */
2279 	default:
2280 		goto invalid_fld;
2281 	}
2282 
2283 	if (six_byte)
2284 		p += 4 + (ebd ? 8 : 0);
2285 	else
2286 		p += 8 + (ebd ? 8 : 0);
2287 
2288 	pg = scsicmd[2] & 0x3f;
2289 	spg = scsicmd[3];
2290 	/*
2291 	 * No mode subpages supported (yet) but asking for _all_
2292 	 * subpages may be valid
2293 	 */
2294 	if (spg && (spg != ALL_SUB_MPAGES))
2295 		goto invalid_fld;
2296 
2297 	switch(pg) {
2298 	case RW_RECOVERY_MPAGE:
2299 		p += ata_msense_rw_recovery(p);
2300 		break;
2301 
2302 	case CACHE_MPAGE:
2303 		p += ata_msense_caching(args->id, p);
2304 		break;
2305 
2306 	case CONTROL_MPAGE:
2307 		p += ata_msense_ctl_mode(p);
2308 		break;
2309 
2310 	case ALL_MPAGES:
2311 		p += ata_msense_rw_recovery(p);
2312 		p += ata_msense_caching(args->id, p);
2313 		p += ata_msense_ctl_mode(p);
2314 		break;
2315 
2316 	default:		/* invalid page code */
2317 		goto invalid_fld;
2318 	}
2319 
2320 	dpofua = 0;
2321 	if (ata_dev_supports_fua(args->id) && (dev->flags & ATA_DFLAG_LBA48) &&
2322 	    (!(dev->flags & ATA_DFLAG_PIO) || dev->multi_count))
2323 		dpofua = 1 << 4;
2324 
2325 	if (six_byte) {
2326 		rbuf[0] = p - rbuf - 1;
2327 		rbuf[2] |= dpofua;
2328 		if (ebd) {
2329 			rbuf[3] = sizeof(sat_blk_desc);
2330 			memcpy(rbuf + 4, sat_blk_desc, sizeof(sat_blk_desc));
2331 		}
2332 	} else {
2333 		unsigned int output_len = p - rbuf - 2;
2334 
2335 		rbuf[0] = output_len >> 8;
2336 		rbuf[1] = output_len;
2337 		rbuf[3] |= dpofua;
2338 		if (ebd) {
2339 			rbuf[7] = sizeof(sat_blk_desc);
2340 			memcpy(rbuf + 8, sat_blk_desc, sizeof(sat_blk_desc));
2341 		}
2342 	}
2343 	return 0;
2344 
2345 invalid_fld:
2346 	ata_scsi_set_sense(args->cmd, ILLEGAL_REQUEST, 0x24, 0x0);
2347 	/* "Invalid field in cbd" */
2348 	return 1;
2349 
2350 saving_not_supp:
2351 	ata_scsi_set_sense(args->cmd, ILLEGAL_REQUEST, 0x39, 0x0);
2352 	 /* "Saving parameters not supported" */
2353 	return 1;
2354 }
2355 
2356 /**
2357  *	ata_scsiop_read_cap - Simulate READ CAPACITY[ 16] commands
2358  *	@args: device IDENTIFY data / SCSI command of interest.
2359  *	@rbuf: Response buffer, to which simulated SCSI cmd output is sent.
2360  *
2361  *	Simulate READ CAPACITY commands.
2362  *
2363  *	LOCKING:
2364  *	None.
2365  */
2366 static unsigned int ata_scsiop_read_cap(struct ata_scsi_args *args, u8 *rbuf)
2367 {
2368 	struct ata_device *dev = args->dev;
2369 	u64 last_lba = dev->n_sectors - 1; /* LBA of the last block */
2370 	u8 log_per_phys = 0;
2371 	u16 lowest_aligned = 0;
2372 	u16 word_106 = dev->id[106];
2373 	u16 word_209 = dev->id[209];
2374 
2375 	if ((word_106 & 0xc000) == 0x4000) {
2376 		/* Number and offset of logical sectors per physical sector */
2377 		if (word_106 & (1 << 13))
2378 			log_per_phys = word_106 & 0xf;
2379 		if ((word_209 & 0xc000) == 0x4000) {
2380 			u16 first = dev->id[209] & 0x3fff;
2381 			if (first > 0)
2382 				lowest_aligned = (1 << log_per_phys) - first;
2383 		}
2384 	}
2385 
2386 	VPRINTK("ENTER\n");
2387 
2388 	if (args->cmd->cmnd[0] == READ_CAPACITY) {
2389 		if (last_lba >= 0xffffffffULL)
2390 			last_lba = 0xffffffff;
2391 
2392 		/* sector count, 32-bit */
2393 		rbuf[0] = last_lba >> (8 * 3);
2394 		rbuf[1] = last_lba >> (8 * 2);
2395 		rbuf[2] = last_lba >> (8 * 1);
2396 		rbuf[3] = last_lba;
2397 
2398 		/* sector size */
2399 		rbuf[6] = ATA_SECT_SIZE >> 8;
2400 		rbuf[7] = ATA_SECT_SIZE & 0xff;
2401 	} else {
2402 		/* sector count, 64-bit */
2403 		rbuf[0] = last_lba >> (8 * 7);
2404 		rbuf[1] = last_lba >> (8 * 6);
2405 		rbuf[2] = last_lba >> (8 * 5);
2406 		rbuf[3] = last_lba >> (8 * 4);
2407 		rbuf[4] = last_lba >> (8 * 3);
2408 		rbuf[5] = last_lba >> (8 * 2);
2409 		rbuf[6] = last_lba >> (8 * 1);
2410 		rbuf[7] = last_lba;
2411 
2412 		/* sector size */
2413 		rbuf[10] = ATA_SECT_SIZE >> 8;
2414 		rbuf[11] = ATA_SECT_SIZE & 0xff;
2415 
2416 		rbuf[12] = 0;
2417 		rbuf[13] = log_per_phys;
2418 		rbuf[14] = (lowest_aligned >> 8) & 0x3f;
2419 		rbuf[15] = lowest_aligned;
2420 
2421 		if (ata_id_has_trim(args->id)) {
2422 			rbuf[14] |= 0x80; /* TPE */
2423 
2424 			if (ata_id_has_zero_after_trim(args->id))
2425 				rbuf[14] |= 0x40; /* TPRZ */
2426 		}
2427 	}
2428 
2429 	return 0;
2430 }
2431 
2432 /**
2433  *	ata_scsiop_report_luns - Simulate REPORT LUNS command
2434  *	@args: device IDENTIFY data / SCSI command of interest.
2435  *	@rbuf: Response buffer, to which simulated SCSI cmd output is sent.
2436  *
2437  *	Simulate REPORT LUNS command.
2438  *
2439  *	LOCKING:
2440  *	spin_lock_irqsave(host lock)
2441  */
2442 static unsigned int ata_scsiop_report_luns(struct ata_scsi_args *args, u8 *rbuf)
2443 {
2444 	VPRINTK("ENTER\n");
2445 	rbuf[3] = 8;	/* just one lun, LUN 0, size 8 bytes */
2446 
2447 	return 0;
2448 }
2449 
2450 static void atapi_sense_complete(struct ata_queued_cmd *qc)
2451 {
2452 	if (qc->err_mask && ((qc->err_mask & AC_ERR_DEV) == 0)) {
2453 		/* FIXME: not quite right; we don't want the
2454 		 * translation of taskfile registers into
2455 		 * a sense descriptors, since that's only
2456 		 * correct for ATA, not ATAPI
2457 		 */
2458 		ata_gen_passthru_sense(qc);
2459 	}
2460 
2461 	qc->scsidone(qc->scsicmd);
2462 	ata_qc_free(qc);
2463 }
2464 
2465 /* is it pointless to prefer PIO for "safety reasons"? */
2466 static inline int ata_pio_use_silly(struct ata_port *ap)
2467 {
2468 	return (ap->flags & ATA_FLAG_PIO_DMA);
2469 }
2470 
2471 static void atapi_request_sense(struct ata_queued_cmd *qc)
2472 {
2473 	struct ata_port *ap = qc->ap;
2474 	struct scsi_cmnd *cmd = qc->scsicmd;
2475 
2476 	DPRINTK("ATAPI request sense\n");
2477 
2478 	/* FIXME: is this needed? */
2479 	memset(cmd->sense_buffer, 0, SCSI_SENSE_BUFFERSIZE);
2480 
2481 #ifdef CONFIG_ATA_SFF
2482 	if (ap->ops->sff_tf_read)
2483 		ap->ops->sff_tf_read(ap, &qc->tf);
2484 #endif
2485 
2486 	/* fill these in, for the case where they are -not- overwritten */
2487 	cmd->sense_buffer[0] = 0x70;
2488 	cmd->sense_buffer[2] = qc->tf.feature >> 4;
2489 
2490 	ata_qc_reinit(qc);
2491 
2492 	/* setup sg table and init transfer direction */
2493 	sg_init_one(&qc->sgent, cmd->sense_buffer, SCSI_SENSE_BUFFERSIZE);
2494 	ata_sg_init(qc, &qc->sgent, 1);
2495 	qc->dma_dir = DMA_FROM_DEVICE;
2496 
2497 	memset(&qc->cdb, 0, qc->dev->cdb_len);
2498 	qc->cdb[0] = REQUEST_SENSE;
2499 	qc->cdb[4] = SCSI_SENSE_BUFFERSIZE;
2500 
2501 	qc->tf.flags |= ATA_TFLAG_ISADDR | ATA_TFLAG_DEVICE;
2502 	qc->tf.command = ATA_CMD_PACKET;
2503 
2504 	if (ata_pio_use_silly(ap)) {
2505 		qc->tf.protocol = ATAPI_PROT_DMA;
2506 		qc->tf.feature |= ATAPI_PKT_DMA;
2507 	} else {
2508 		qc->tf.protocol = ATAPI_PROT_PIO;
2509 		qc->tf.lbam = SCSI_SENSE_BUFFERSIZE;
2510 		qc->tf.lbah = 0;
2511 	}
2512 	qc->nbytes = SCSI_SENSE_BUFFERSIZE;
2513 
2514 	qc->complete_fn = atapi_sense_complete;
2515 
2516 	ata_qc_issue(qc);
2517 
2518 	DPRINTK("EXIT\n");
2519 }
2520 
2521 static void atapi_qc_complete(struct ata_queued_cmd *qc)
2522 {
2523 	struct scsi_cmnd *cmd = qc->scsicmd;
2524 	unsigned int err_mask = qc->err_mask;
2525 
2526 	VPRINTK("ENTER, err_mask 0x%X\n", err_mask);
2527 
2528 	/* handle completion from new EH */
2529 	if (unlikely(qc->ap->ops->error_handler &&
2530 		     (err_mask || qc->flags & ATA_QCFLAG_SENSE_VALID))) {
2531 
2532 		if (!(qc->flags & ATA_QCFLAG_SENSE_VALID)) {
2533 			/* FIXME: not quite right; we don't want the
2534 			 * translation of taskfile registers into a
2535 			 * sense descriptors, since that's only
2536 			 * correct for ATA, not ATAPI
2537 			 */
2538 			ata_gen_passthru_sense(qc);
2539 		}
2540 
2541 		/* SCSI EH automatically locks door if sdev->locked is
2542 		 * set.  Sometimes door lock request continues to
2543 		 * fail, for example, when no media is present.  This
2544 		 * creates a loop - SCSI EH issues door lock which
2545 		 * fails and gets invoked again to acquire sense data
2546 		 * for the failed command.
2547 		 *
2548 		 * If door lock fails, always clear sdev->locked to
2549 		 * avoid this infinite loop.
2550 		 */
2551 		if (qc->cdb[0] == ALLOW_MEDIUM_REMOVAL)
2552 			qc->dev->sdev->locked = 0;
2553 
2554 		qc->scsicmd->result = SAM_STAT_CHECK_CONDITION;
2555 		qc->scsidone(cmd);
2556 		ata_qc_free(qc);
2557 		return;
2558 	}
2559 
2560 	/* successful completion or old EH failure path */
2561 	if (unlikely(err_mask & AC_ERR_DEV)) {
2562 		cmd->result = SAM_STAT_CHECK_CONDITION;
2563 		atapi_request_sense(qc);
2564 		return;
2565 	} else if (unlikely(err_mask)) {
2566 		/* FIXME: not quite right; we don't want the
2567 		 * translation of taskfile registers into
2568 		 * a sense descriptors, since that's only
2569 		 * correct for ATA, not ATAPI
2570 		 */
2571 		ata_gen_passthru_sense(qc);
2572 	} else {
2573 		u8 *scsicmd = cmd->cmnd;
2574 
2575 		if ((scsicmd[0] == INQUIRY) && ((scsicmd[1] & 0x03) == 0)) {
2576 			unsigned long flags;
2577 			u8 *buf;
2578 
2579 			buf = ata_scsi_rbuf_get(cmd, true, &flags);
2580 
2581 	/* ATAPI devices typically report zero for their SCSI version,
2582 	 * and sometimes deviate from the spec WRT response data
2583 	 * format.  If SCSI version is reported as zero like normal,
2584 	 * then we make the following fixups:  1) Fake MMC-5 version,
2585 	 * to indicate to the Linux scsi midlayer this is a modern
2586 	 * device.  2) Ensure response data format / ATAPI information
2587 	 * are always correct.
2588 	 */
2589 			if (buf[2] == 0) {
2590 				buf[2] = 0x5;
2591 				buf[3] = 0x32;
2592 			}
2593 
2594 			ata_scsi_rbuf_put(cmd, true, &flags);
2595 		}
2596 
2597 		cmd->result = SAM_STAT_GOOD;
2598 	}
2599 
2600 	qc->scsidone(cmd);
2601 	ata_qc_free(qc);
2602 }
2603 /**
2604  *	atapi_xlat - Initialize PACKET taskfile
2605  *	@qc: command structure to be initialized
2606  *
2607  *	LOCKING:
2608  *	spin_lock_irqsave(host lock)
2609  *
2610  *	RETURNS:
2611  *	Zero on success, non-zero on failure.
2612  */
2613 static unsigned int atapi_xlat(struct ata_queued_cmd *qc)
2614 {
2615 	struct scsi_cmnd *scmd = qc->scsicmd;
2616 	struct ata_device *dev = qc->dev;
2617 	int nodata = (scmd->sc_data_direction == DMA_NONE);
2618 	int using_pio = !nodata && (dev->flags & ATA_DFLAG_PIO);
2619 	unsigned int nbytes;
2620 
2621 	memset(qc->cdb, 0, dev->cdb_len);
2622 	memcpy(qc->cdb, scmd->cmnd, scmd->cmd_len);
2623 
2624 	qc->complete_fn = atapi_qc_complete;
2625 
2626 	qc->tf.flags |= ATA_TFLAG_ISADDR | ATA_TFLAG_DEVICE;
2627 	if (scmd->sc_data_direction == DMA_TO_DEVICE) {
2628 		qc->tf.flags |= ATA_TFLAG_WRITE;
2629 		DPRINTK("direction: write\n");
2630 	}
2631 
2632 	qc->tf.command = ATA_CMD_PACKET;
2633 	ata_qc_set_pc_nbytes(qc);
2634 
2635 	/* check whether ATAPI DMA is safe */
2636 	if (!nodata && !using_pio && atapi_check_dma(qc))
2637 		using_pio = 1;
2638 
2639 	/* Some controller variants snoop this value for Packet
2640 	 * transfers to do state machine and FIFO management.  Thus we
2641 	 * want to set it properly, and for DMA where it is
2642 	 * effectively meaningless.
2643 	 */
2644 	nbytes = min(ata_qc_raw_nbytes(qc), (unsigned int)63 * 1024);
2645 
2646 	/* Most ATAPI devices which honor transfer chunk size don't
2647 	 * behave according to the spec when odd chunk size which
2648 	 * matches the transfer length is specified.  If the number of
2649 	 * bytes to transfer is 2n+1.  According to the spec, what
2650 	 * should happen is to indicate that 2n+1 is going to be
2651 	 * transferred and transfer 2n+2 bytes where the last byte is
2652 	 * padding.
2653 	 *
2654 	 * In practice, this doesn't happen.  ATAPI devices first
2655 	 * indicate and transfer 2n bytes and then indicate and
2656 	 * transfer 2 bytes where the last byte is padding.
2657 	 *
2658 	 * This inconsistency confuses several controllers which
2659 	 * perform PIO using DMA such as Intel AHCIs and sil3124/32.
2660 	 * These controllers use actual number of transferred bytes to
2661 	 * update DMA poitner and transfer of 4n+2 bytes make those
2662 	 * controller push DMA pointer by 4n+4 bytes because SATA data
2663 	 * FISes are aligned to 4 bytes.  This causes data corruption
2664 	 * and buffer overrun.
2665 	 *
2666 	 * Always setting nbytes to even number solves this problem
2667 	 * because then ATAPI devices don't have to split data at 2n
2668 	 * boundaries.
2669 	 */
2670 	if (nbytes & 0x1)
2671 		nbytes++;
2672 
2673 	qc->tf.lbam = (nbytes & 0xFF);
2674 	qc->tf.lbah = (nbytes >> 8);
2675 
2676 	if (nodata)
2677 		qc->tf.protocol = ATAPI_PROT_NODATA;
2678 	else if (using_pio)
2679 		qc->tf.protocol = ATAPI_PROT_PIO;
2680 	else {
2681 		/* DMA data xfer */
2682 		qc->tf.protocol = ATAPI_PROT_DMA;
2683 		qc->tf.feature |= ATAPI_PKT_DMA;
2684 
2685 		if ((dev->flags & ATA_DFLAG_DMADIR) &&
2686 		    (scmd->sc_data_direction != DMA_TO_DEVICE))
2687 			/* some SATA bridges need us to indicate data xfer direction */
2688 			qc->tf.feature |= ATAPI_DMADIR;
2689 	}
2690 
2691 
2692 	/* FIXME: We need to translate 0x05 READ_BLOCK_LIMITS to a MODE_SENSE
2693 	   as ATAPI tape drives don't get this right otherwise */
2694 	return 0;
2695 }
2696 
2697 static struct ata_device *ata_find_dev(struct ata_port *ap, int devno)
2698 {
2699 	if (!sata_pmp_attached(ap)) {
2700 		if (likely(devno < ata_link_max_devices(&ap->link)))
2701 			return &ap->link.device[devno];
2702 	} else {
2703 		if (likely(devno < ap->nr_pmp_links))
2704 			return &ap->pmp_link[devno].device[0];
2705 	}
2706 
2707 	return NULL;
2708 }
2709 
2710 static struct ata_device *__ata_scsi_find_dev(struct ata_port *ap,
2711 					      const struct scsi_device *scsidev)
2712 {
2713 	int devno;
2714 
2715 	/* skip commands not addressed to targets we simulate */
2716 	if (!sata_pmp_attached(ap)) {
2717 		if (unlikely(scsidev->channel || scsidev->lun))
2718 			return NULL;
2719 		devno = scsidev->id;
2720 	} else {
2721 		if (unlikely(scsidev->id || scsidev->lun))
2722 			return NULL;
2723 		devno = scsidev->channel;
2724 	}
2725 
2726 	return ata_find_dev(ap, devno);
2727 }
2728 
2729 /**
2730  *	ata_scsi_find_dev - lookup ata_device from scsi_cmnd
2731  *	@ap: ATA port to which the device is attached
2732  *	@scsidev: SCSI device from which we derive the ATA device
2733  *
2734  *	Given various information provided in struct scsi_cmnd,
2735  *	map that onto an ATA bus, and using that mapping
2736  *	determine which ata_device is associated with the
2737  *	SCSI command to be sent.
2738  *
2739  *	LOCKING:
2740  *	spin_lock_irqsave(host lock)
2741  *
2742  *	RETURNS:
2743  *	Associated ATA device, or %NULL if not found.
2744  */
2745 static struct ata_device *
2746 ata_scsi_find_dev(struct ata_port *ap, const struct scsi_device *scsidev)
2747 {
2748 	struct ata_device *dev = __ata_scsi_find_dev(ap, scsidev);
2749 
2750 	if (unlikely(!dev || !ata_dev_enabled(dev)))
2751 		return NULL;
2752 
2753 	return dev;
2754 }
2755 
2756 /*
2757  *	ata_scsi_map_proto - Map pass-thru protocol value to taskfile value.
2758  *	@byte1: Byte 1 from pass-thru CDB.
2759  *
2760  *	RETURNS:
2761  *	ATA_PROT_UNKNOWN if mapping failed/unimplemented, protocol otherwise.
2762  */
2763 static u8
2764 ata_scsi_map_proto(u8 byte1)
2765 {
2766 	switch((byte1 & 0x1e) >> 1) {
2767 	case 3:		/* Non-data */
2768 		return ATA_PROT_NODATA;
2769 
2770 	case 6:		/* DMA */
2771 	case 10:	/* UDMA Data-in */
2772 	case 11:	/* UDMA Data-Out */
2773 		return ATA_PROT_DMA;
2774 
2775 	case 4:		/* PIO Data-in */
2776 	case 5:		/* PIO Data-out */
2777 		return ATA_PROT_PIO;
2778 
2779 	case 0:		/* Hard Reset */
2780 	case 1:		/* SRST */
2781 	case 8:		/* Device Diagnostic */
2782 	case 9:		/* Device Reset */
2783 	case 7:		/* DMA Queued */
2784 	case 12:	/* FPDMA */
2785 	case 15:	/* Return Response Info */
2786 	default:	/* Reserved */
2787 		break;
2788 	}
2789 
2790 	return ATA_PROT_UNKNOWN;
2791 }
2792 
2793 /**
2794  *	ata_scsi_pass_thru - convert ATA pass-thru CDB to taskfile
2795  *	@qc: command structure to be initialized
2796  *
2797  *	Handles either 12 or 16-byte versions of the CDB.
2798  *
2799  *	RETURNS:
2800  *	Zero on success, non-zero on failure.
2801  */
2802 static unsigned int ata_scsi_pass_thru(struct ata_queued_cmd *qc)
2803 {
2804 	struct ata_taskfile *tf = &(qc->tf);
2805 	struct scsi_cmnd *scmd = qc->scsicmd;
2806 	struct ata_device *dev = qc->dev;
2807 	const u8 *cdb = scmd->cmnd;
2808 
2809 	if ((tf->protocol = ata_scsi_map_proto(cdb[1])) == ATA_PROT_UNKNOWN)
2810 		goto invalid_fld;
2811 
2812 	/*
2813 	 * 12 and 16 byte CDBs use different offsets to
2814 	 * provide the various register values.
2815 	 */
2816 	if (cdb[0] == ATA_16) {
2817 		/*
2818 		 * 16-byte CDB - may contain extended commands.
2819 		 *
2820 		 * If that is the case, copy the upper byte register values.
2821 		 */
2822 		if (cdb[1] & 0x01) {
2823 			tf->hob_feature = cdb[3];
2824 			tf->hob_nsect = cdb[5];
2825 			tf->hob_lbal = cdb[7];
2826 			tf->hob_lbam = cdb[9];
2827 			tf->hob_lbah = cdb[11];
2828 			tf->flags |= ATA_TFLAG_LBA48;
2829 		} else
2830 			tf->flags &= ~ATA_TFLAG_LBA48;
2831 
2832 		/*
2833 		 * Always copy low byte, device and command registers.
2834 		 */
2835 		tf->feature = cdb[4];
2836 		tf->nsect = cdb[6];
2837 		tf->lbal = cdb[8];
2838 		tf->lbam = cdb[10];
2839 		tf->lbah = cdb[12];
2840 		tf->device = cdb[13];
2841 		tf->command = cdb[14];
2842 	} else {
2843 		/*
2844 		 * 12-byte CDB - incapable of extended commands.
2845 		 */
2846 		tf->flags &= ~ATA_TFLAG_LBA48;
2847 
2848 		tf->feature = cdb[3];
2849 		tf->nsect = cdb[4];
2850 		tf->lbal = cdb[5];
2851 		tf->lbam = cdb[6];
2852 		tf->lbah = cdb[7];
2853 		tf->device = cdb[8];
2854 		tf->command = cdb[9];
2855 	}
2856 
2857 	/* enforce correct master/slave bit */
2858 	tf->device = dev->devno ?
2859 		tf->device | ATA_DEV1 : tf->device & ~ATA_DEV1;
2860 
2861 	/* READ/WRITE LONG use a non-standard sect_size */
2862 	qc->sect_size = ATA_SECT_SIZE;
2863 	switch (tf->command) {
2864 	case ATA_CMD_READ_LONG:
2865 	case ATA_CMD_READ_LONG_ONCE:
2866 	case ATA_CMD_WRITE_LONG:
2867 	case ATA_CMD_WRITE_LONG_ONCE:
2868 		if (tf->protocol != ATA_PROT_PIO || tf->nsect != 1)
2869 			goto invalid_fld;
2870 		qc->sect_size = scsi_bufflen(scmd);
2871 	}
2872 
2873 	/*
2874 	 * Set flags so that all registers will be written, pass on
2875 	 * write indication (used for PIO/DMA setup), result TF is
2876 	 * copied back and we don't whine too much about its failure.
2877 	 */
2878 	tf->flags = ATA_TFLAG_ISADDR | ATA_TFLAG_DEVICE;
2879 	if (scmd->sc_data_direction == DMA_TO_DEVICE)
2880 		tf->flags |= ATA_TFLAG_WRITE;
2881 
2882 	qc->flags |= ATA_QCFLAG_RESULT_TF | ATA_QCFLAG_QUIET;
2883 
2884 	/*
2885 	 * Set transfer length.
2886 	 *
2887 	 * TODO: find out if we need to do more here to
2888 	 *       cover scatter/gather case.
2889 	 */
2890 	ata_qc_set_pc_nbytes(qc);
2891 
2892 	/* We may not issue DMA commands if no DMA mode is set */
2893 	if (tf->protocol == ATA_PROT_DMA && dev->dma_mode == 0)
2894 		goto invalid_fld;
2895 
2896 	/* sanity check for pio multi commands */
2897 	if ((cdb[1] & 0xe0) && !is_multi_taskfile(tf))
2898 		goto invalid_fld;
2899 
2900 	if (is_multi_taskfile(tf)) {
2901 		unsigned int multi_count = 1 << (cdb[1] >> 5);
2902 
2903 		/* compare the passed through multi_count
2904 		 * with the cached multi_count of libata
2905 		 */
2906 		if (multi_count != dev->multi_count)
2907 			ata_dev_printk(dev, KERN_WARNING,
2908 				       "invalid multi_count %u ignored\n",
2909 				       multi_count);
2910 	}
2911 
2912 	/*
2913 	 * Filter SET_FEATURES - XFER MODE command -- otherwise,
2914 	 * SET_FEATURES - XFER MODE must be preceded/succeeded
2915 	 * by an update to hardware-specific registers for each
2916 	 * controller (i.e. the reason for ->set_piomode(),
2917 	 * ->set_dmamode(), and ->post_set_mode() hooks).
2918 	 */
2919 	if (tf->command == ATA_CMD_SET_FEATURES &&
2920 	    tf->feature == SETFEATURES_XFER)
2921 		goto invalid_fld;
2922 
2923 	/*
2924 	 * Filter TPM commands by default. These provide an
2925 	 * essentially uncontrolled encrypted "back door" between
2926 	 * applications and the disk. Set libata.allow_tpm=1 if you
2927 	 * have a real reason for wanting to use them. This ensures
2928 	 * that installed software cannot easily mess stuff up without
2929 	 * user intent. DVR type users will probably ship with this enabled
2930 	 * for movie content management.
2931 	 *
2932 	 * Note that for ATA8 we can issue a DCS change and DCS freeze lock
2933 	 * for this and should do in future but that it is not sufficient as
2934 	 * DCS is an optional feature set. Thus we also do the software filter
2935 	 * so that we comply with the TC consortium stated goal that the user
2936 	 * can turn off TC features of their system.
2937 	 */
2938 	if (tf->command >= 0x5C && tf->command <= 0x5F && !libata_allow_tpm)
2939 		goto invalid_fld;
2940 
2941 	return 0;
2942 
2943  invalid_fld:
2944 	ata_scsi_set_sense(scmd, ILLEGAL_REQUEST, 0x24, 0x00);
2945 	/* "Invalid field in cdb" */
2946 	return 1;
2947 }
2948 
2949 static unsigned int ata_scsi_write_same_xlat(struct ata_queued_cmd *qc)
2950 {
2951 	struct ata_taskfile *tf = &qc->tf;
2952 	struct scsi_cmnd *scmd = qc->scsicmd;
2953 	struct ata_device *dev = qc->dev;
2954 	const u8 *cdb = scmd->cmnd;
2955 	u64 block;
2956 	u32 n_block;
2957 	u32 size;
2958 	void *buf;
2959 
2960 	/* we may not issue DMA commands if no DMA mode is set */
2961 	if (unlikely(!dev->dma_mode))
2962 		goto invalid_fld;
2963 
2964 	if (unlikely(scmd->cmd_len < 16))
2965 		goto invalid_fld;
2966 	scsi_16_lba_len(cdb, &block, &n_block);
2967 
2968 	/* for now we only support WRITE SAME with the unmap bit set */
2969 	if (unlikely(!(cdb[1] & 0x8)))
2970 		goto invalid_fld;
2971 
2972 	/*
2973 	 * WRITE SAME always has a sector sized buffer as payload, this
2974 	 * should never be a multiple entry S/G list.
2975 	 */
2976 	if (!scsi_sg_count(scmd))
2977 		goto invalid_fld;
2978 
2979 	buf = page_address(sg_page(scsi_sglist(scmd)));
2980 	size = ata_set_lba_range_entries(buf, 512, block, n_block);
2981 
2982 	tf->protocol = ATA_PROT_DMA;
2983 	tf->hob_feature = 0;
2984 	tf->feature = ATA_DSM_TRIM;
2985 	tf->hob_nsect = (size / 512) >> 8;
2986 	tf->nsect = size / 512;
2987 	tf->command = ATA_CMD_DSM;
2988 	tf->flags |= ATA_TFLAG_ISADDR | ATA_TFLAG_DEVICE | ATA_TFLAG_LBA48 |
2989 		     ATA_TFLAG_WRITE;
2990 
2991 	ata_qc_set_pc_nbytes(qc);
2992 
2993 	return 0;
2994 
2995  invalid_fld:
2996 	ata_scsi_set_sense(scmd, ILLEGAL_REQUEST, 0x24, 0x00);
2997 	/* "Invalid field in cdb" */
2998 	return 1;
2999 }
3000 
3001 /**
3002  *	ata_get_xlat_func - check if SCSI to ATA translation is possible
3003  *	@dev: ATA device
3004  *	@cmd: SCSI command opcode to consider
3005  *
3006  *	Look up the SCSI command given, and determine whether the
3007  *	SCSI command is to be translated or simulated.
3008  *
3009  *	RETURNS:
3010  *	Pointer to translation function if possible, %NULL if not.
3011  */
3012 
3013 static inline ata_xlat_func_t ata_get_xlat_func(struct ata_device *dev, u8 cmd)
3014 {
3015 	switch (cmd) {
3016 	case READ_6:
3017 	case READ_10:
3018 	case READ_16:
3019 
3020 	case WRITE_6:
3021 	case WRITE_10:
3022 	case WRITE_16:
3023 		return ata_scsi_rw_xlat;
3024 
3025 	case WRITE_SAME_16:
3026 		return ata_scsi_write_same_xlat;
3027 
3028 	case SYNCHRONIZE_CACHE:
3029 		if (ata_try_flush_cache(dev))
3030 			return ata_scsi_flush_xlat;
3031 		break;
3032 
3033 	case VERIFY:
3034 	case VERIFY_16:
3035 		return ata_scsi_verify_xlat;
3036 
3037 	case ATA_12:
3038 	case ATA_16:
3039 		return ata_scsi_pass_thru;
3040 
3041 	case START_STOP:
3042 		return ata_scsi_start_stop_xlat;
3043 	}
3044 
3045 	return NULL;
3046 }
3047 
3048 /**
3049  *	ata_scsi_dump_cdb - dump SCSI command contents to dmesg
3050  *	@ap: ATA port to which the command was being sent
3051  *	@cmd: SCSI command to dump
3052  *
3053  *	Prints the contents of a SCSI command via printk().
3054  */
3055 
3056 static inline void ata_scsi_dump_cdb(struct ata_port *ap,
3057 				     struct scsi_cmnd *cmd)
3058 {
3059 #ifdef ATA_DEBUG
3060 	struct scsi_device *scsidev = cmd->device;
3061 	u8 *scsicmd = cmd->cmnd;
3062 
3063 	DPRINTK("CDB (%u:%d,%d,%d) %02x %02x %02x %02x %02x %02x %02x %02x %02x\n",
3064 		ap->print_id,
3065 		scsidev->channel, scsidev->id, scsidev->lun,
3066 		scsicmd[0], scsicmd[1], scsicmd[2], scsicmd[3],
3067 		scsicmd[4], scsicmd[5], scsicmd[6], scsicmd[7],
3068 		scsicmd[8]);
3069 #endif
3070 }
3071 
3072 static inline int __ata_scsi_queuecmd(struct scsi_cmnd *scmd,
3073 				      void (*done)(struct scsi_cmnd *),
3074 				      struct ata_device *dev)
3075 {
3076 	u8 scsi_op = scmd->cmnd[0];
3077 	ata_xlat_func_t xlat_func;
3078 	int rc = 0;
3079 
3080 	if (dev->class == ATA_DEV_ATA) {
3081 		if (unlikely(!scmd->cmd_len || scmd->cmd_len > dev->cdb_len))
3082 			goto bad_cdb_len;
3083 
3084 		xlat_func = ata_get_xlat_func(dev, scsi_op);
3085 	} else {
3086 		if (unlikely(!scmd->cmd_len))
3087 			goto bad_cdb_len;
3088 
3089 		xlat_func = NULL;
3090 		if (likely((scsi_op != ATA_16) || !atapi_passthru16)) {
3091 			/* relay SCSI command to ATAPI device */
3092 			int len = COMMAND_SIZE(scsi_op);
3093 			if (unlikely(len > scmd->cmd_len || len > dev->cdb_len))
3094 				goto bad_cdb_len;
3095 
3096 			xlat_func = atapi_xlat;
3097 		} else {
3098 			/* ATA_16 passthru, treat as an ATA command */
3099 			if (unlikely(scmd->cmd_len > 16))
3100 				goto bad_cdb_len;
3101 
3102 			xlat_func = ata_get_xlat_func(dev, scsi_op);
3103 		}
3104 	}
3105 
3106 	if (xlat_func)
3107 		rc = ata_scsi_translate(dev, scmd, done, xlat_func);
3108 	else
3109 		ata_scsi_simulate(dev, scmd, done);
3110 
3111 	return rc;
3112 
3113  bad_cdb_len:
3114 	DPRINTK("bad CDB len=%u, scsi_op=0x%02x, max=%u\n",
3115 		scmd->cmd_len, scsi_op, dev->cdb_len);
3116 	scmd->result = DID_ERROR << 16;
3117 	done(scmd);
3118 	return 0;
3119 }
3120 
3121 /**
3122  *	ata_scsi_queuecmd - Issue SCSI cdb to libata-managed device
3123  *	@cmd: SCSI command to be sent
3124  *	@done: Completion function, called when command is complete
3125  *
3126  *	In some cases, this function translates SCSI commands into
3127  *	ATA taskfiles, and queues the taskfiles to be sent to
3128  *	hardware.  In other cases, this function simulates a
3129  *	SCSI device by evaluating and responding to certain
3130  *	SCSI commands.  This creates the overall effect of
3131  *	ATA and ATAPI devices appearing as SCSI devices.
3132  *
3133  *	LOCKING:
3134  *	Releases scsi-layer-held lock, and obtains host lock.
3135  *
3136  *	RETURNS:
3137  *	Return value from __ata_scsi_queuecmd() if @cmd can be queued,
3138  *	0 otherwise.
3139  */
3140 int ata_scsi_queuecmd(struct scsi_cmnd *cmd, void (*done)(struct scsi_cmnd *))
3141 {
3142 	struct ata_port *ap;
3143 	struct ata_device *dev;
3144 	struct scsi_device *scsidev = cmd->device;
3145 	struct Scsi_Host *shost = scsidev->host;
3146 	int rc = 0;
3147 
3148 	ap = ata_shost_to_port(shost);
3149 
3150 	spin_unlock(shost->host_lock);
3151 	spin_lock(ap->lock);
3152 
3153 	ata_scsi_dump_cdb(ap, cmd);
3154 
3155 	dev = ata_scsi_find_dev(ap, scsidev);
3156 	if (likely(dev))
3157 		rc = __ata_scsi_queuecmd(cmd, done, dev);
3158 	else {
3159 		cmd->result = (DID_BAD_TARGET << 16);
3160 		done(cmd);
3161 	}
3162 
3163 	spin_unlock(ap->lock);
3164 	spin_lock(shost->host_lock);
3165 	return rc;
3166 }
3167 
3168 /**
3169  *	ata_scsi_simulate - simulate SCSI command on ATA device
3170  *	@dev: the target device
3171  *	@cmd: SCSI command being sent to device.
3172  *	@done: SCSI command completion function.
3173  *
3174  *	Interprets and directly executes a select list of SCSI commands
3175  *	that can be handled internally.
3176  *
3177  *	LOCKING:
3178  *	spin_lock_irqsave(host lock)
3179  */
3180 
3181 void ata_scsi_simulate(struct ata_device *dev, struct scsi_cmnd *cmd,
3182 		      void (*done)(struct scsi_cmnd *))
3183 {
3184 	struct ata_scsi_args args;
3185 	const u8 *scsicmd = cmd->cmnd;
3186 	u8 tmp8;
3187 
3188 	args.dev = dev;
3189 	args.id = dev->id;
3190 	args.cmd = cmd;
3191 	args.done = done;
3192 
3193 	switch(scsicmd[0]) {
3194 	/* TODO: worth improving? */
3195 	case FORMAT_UNIT:
3196 		ata_scsi_invalid_field(cmd, done);
3197 		break;
3198 
3199 	case INQUIRY:
3200 		if (scsicmd[1] & 2)	           /* is CmdDt set?  */
3201 			ata_scsi_invalid_field(cmd, done);
3202 		else if ((scsicmd[1] & 1) == 0)    /* is EVPD clear? */
3203 			ata_scsi_rbuf_fill(&args, ata_scsiop_inq_std);
3204 		else switch (scsicmd[2]) {
3205 		case 0x00:
3206 			ata_scsi_rbuf_fill(&args, ata_scsiop_inq_00);
3207 			break;
3208 		case 0x80:
3209 			ata_scsi_rbuf_fill(&args, ata_scsiop_inq_80);
3210 			break;
3211 		case 0x83:
3212 			ata_scsi_rbuf_fill(&args, ata_scsiop_inq_83);
3213 			break;
3214 		case 0x89:
3215 			ata_scsi_rbuf_fill(&args, ata_scsiop_inq_89);
3216 			break;
3217 		case 0xb0:
3218 			ata_scsi_rbuf_fill(&args, ata_scsiop_inq_b0);
3219 			break;
3220 		case 0xb1:
3221 			ata_scsi_rbuf_fill(&args, ata_scsiop_inq_b1);
3222 			break;
3223 		default:
3224 			ata_scsi_invalid_field(cmd, done);
3225 			break;
3226 		}
3227 		break;
3228 
3229 	case MODE_SENSE:
3230 	case MODE_SENSE_10:
3231 		ata_scsi_rbuf_fill(&args, ata_scsiop_mode_sense);
3232 		break;
3233 
3234 	case MODE_SELECT:	/* unconditionally return */
3235 	case MODE_SELECT_10:	/* bad-field-in-cdb */
3236 		ata_scsi_invalid_field(cmd, done);
3237 		break;
3238 
3239 	case READ_CAPACITY:
3240 		ata_scsi_rbuf_fill(&args, ata_scsiop_read_cap);
3241 		break;
3242 
3243 	case SERVICE_ACTION_IN:
3244 		if ((scsicmd[1] & 0x1f) == SAI_READ_CAPACITY_16)
3245 			ata_scsi_rbuf_fill(&args, ata_scsiop_read_cap);
3246 		else
3247 			ata_scsi_invalid_field(cmd, done);
3248 		break;
3249 
3250 	case REPORT_LUNS:
3251 		ata_scsi_rbuf_fill(&args, ata_scsiop_report_luns);
3252 		break;
3253 
3254 	case REQUEST_SENSE:
3255 		ata_scsi_set_sense(cmd, 0, 0, 0);
3256 		cmd->result = (DRIVER_SENSE << 24);
3257 		done(cmd);
3258 		break;
3259 
3260 	/* if we reach this, then writeback caching is disabled,
3261 	 * turning this into a no-op.
3262 	 */
3263 	case SYNCHRONIZE_CACHE:
3264 		/* fall through */
3265 
3266 	/* no-op's, complete with success */
3267 	case REZERO_UNIT:
3268 	case SEEK_6:
3269 	case SEEK_10:
3270 	case TEST_UNIT_READY:
3271 		ata_scsi_rbuf_fill(&args, ata_scsiop_noop);
3272 		break;
3273 
3274 	case SEND_DIAGNOSTIC:
3275 		tmp8 = scsicmd[1] & ~(1 << 3);
3276 		if ((tmp8 == 0x4) && (!scsicmd[3]) && (!scsicmd[4]))
3277 			ata_scsi_rbuf_fill(&args, ata_scsiop_noop);
3278 		else
3279 			ata_scsi_invalid_field(cmd, done);
3280 		break;
3281 
3282 	/* all other commands */
3283 	default:
3284 		ata_scsi_set_sense(cmd, ILLEGAL_REQUEST, 0x20, 0x0);
3285 		/* "Invalid command operation code" */
3286 		done(cmd);
3287 		break;
3288 	}
3289 }
3290 
3291 int ata_scsi_add_hosts(struct ata_host *host, struct scsi_host_template *sht)
3292 {
3293 	int i, rc;
3294 
3295 	for (i = 0; i < host->n_ports; i++) {
3296 		struct ata_port *ap = host->ports[i];
3297 		struct Scsi_Host *shost;
3298 
3299 		rc = -ENOMEM;
3300 		shost = scsi_host_alloc(sht, sizeof(struct ata_port *));
3301 		if (!shost)
3302 			goto err_alloc;
3303 
3304 		*(struct ata_port **)&shost->hostdata[0] = ap;
3305 		ap->scsi_host = shost;
3306 
3307 		shost->transportt = &ata_scsi_transport_template;
3308 		shost->unique_id = ap->print_id;
3309 		shost->max_id = 16;
3310 		shost->max_lun = 1;
3311 		shost->max_channel = 1;
3312 		shost->max_cmd_len = 16;
3313 
3314 		/* Schedule policy is determined by ->qc_defer()
3315 		 * callback and it needs to see every deferred qc.
3316 		 * Set host_blocked to 1 to prevent SCSI midlayer from
3317 		 * automatically deferring requests.
3318 		 */
3319 		shost->max_host_blocked = 1;
3320 
3321 		rc = scsi_add_host(ap->scsi_host, ap->host->dev);
3322 		if (rc)
3323 			goto err_add;
3324 	}
3325 
3326 	return 0;
3327 
3328  err_add:
3329 	scsi_host_put(host->ports[i]->scsi_host);
3330  err_alloc:
3331 	while (--i >= 0) {
3332 		struct Scsi_Host *shost = host->ports[i]->scsi_host;
3333 
3334 		scsi_remove_host(shost);
3335 		scsi_host_put(shost);
3336 	}
3337 	return rc;
3338 }
3339 
3340 void ata_scsi_scan_host(struct ata_port *ap, int sync)
3341 {
3342 	int tries = 5;
3343 	struct ata_device *last_failed_dev = NULL;
3344 	struct ata_link *link;
3345 	struct ata_device *dev;
3346 
3347 	if (ap->flags & ATA_FLAG_DISABLED)
3348 		return;
3349 
3350  repeat:
3351 	ata_for_each_link(link, ap, EDGE) {
3352 		ata_for_each_dev(dev, link, ENABLED) {
3353 			struct scsi_device *sdev;
3354 			int channel = 0, id = 0;
3355 
3356 			if (dev->sdev)
3357 				continue;
3358 
3359 			if (ata_is_host_link(link))
3360 				id = dev->devno;
3361 			else
3362 				channel = link->pmp;
3363 
3364 			sdev = __scsi_add_device(ap->scsi_host, channel, id, 0,
3365 						 NULL);
3366 			if (!IS_ERR(sdev)) {
3367 				dev->sdev = sdev;
3368 				scsi_device_put(sdev);
3369 			}
3370 		}
3371 	}
3372 
3373 	/* If we scanned while EH was in progress or allocation
3374 	 * failure occurred, scan would have failed silently.  Check
3375 	 * whether all devices are attached.
3376 	 */
3377 	ata_for_each_link(link, ap, EDGE) {
3378 		ata_for_each_dev(dev, link, ENABLED) {
3379 			if (!dev->sdev)
3380 				goto exit_loop;
3381 		}
3382 	}
3383  exit_loop:
3384 	if (!link)
3385 		return;
3386 
3387 	/* we're missing some SCSI devices */
3388 	if (sync) {
3389 		/* If caller requested synchrnous scan && we've made
3390 		 * any progress, sleep briefly and repeat.
3391 		 */
3392 		if (dev != last_failed_dev) {
3393 			msleep(100);
3394 			last_failed_dev = dev;
3395 			goto repeat;
3396 		}
3397 
3398 		/* We might be failing to detect boot device, give it
3399 		 * a few more chances.
3400 		 */
3401 		if (--tries) {
3402 			msleep(100);
3403 			goto repeat;
3404 		}
3405 
3406 		ata_port_printk(ap, KERN_ERR, "WARNING: synchronous SCSI scan "
3407 				"failed without making any progress,\n"
3408 				"                  switching to async\n");
3409 	}
3410 
3411 	queue_delayed_work(ata_aux_wq, &ap->hotplug_task,
3412 			   round_jiffies_relative(HZ));
3413 }
3414 
3415 /**
3416  *	ata_scsi_offline_dev - offline attached SCSI device
3417  *	@dev: ATA device to offline attached SCSI device for
3418  *
3419  *	This function is called from ata_eh_hotplug() and responsible
3420  *	for taking the SCSI device attached to @dev offline.  This
3421  *	function is called with host lock which protects dev->sdev
3422  *	against clearing.
3423  *
3424  *	LOCKING:
3425  *	spin_lock_irqsave(host lock)
3426  *
3427  *	RETURNS:
3428  *	1 if attached SCSI device exists, 0 otherwise.
3429  */
3430 int ata_scsi_offline_dev(struct ata_device *dev)
3431 {
3432 	if (dev->sdev) {
3433 		scsi_device_set_state(dev->sdev, SDEV_OFFLINE);
3434 		return 1;
3435 	}
3436 	return 0;
3437 }
3438 
3439 /**
3440  *	ata_scsi_remove_dev - remove attached SCSI device
3441  *	@dev: ATA device to remove attached SCSI device for
3442  *
3443  *	This function is called from ata_eh_scsi_hotplug() and
3444  *	responsible for removing the SCSI device attached to @dev.
3445  *
3446  *	LOCKING:
3447  *	Kernel thread context (may sleep).
3448  */
3449 static void ata_scsi_remove_dev(struct ata_device *dev)
3450 {
3451 	struct ata_port *ap = dev->link->ap;
3452 	struct scsi_device *sdev;
3453 	unsigned long flags;
3454 
3455 	/* Alas, we need to grab scan_mutex to ensure SCSI device
3456 	 * state doesn't change underneath us and thus
3457 	 * scsi_device_get() always succeeds.  The mutex locking can
3458 	 * be removed if there is __scsi_device_get() interface which
3459 	 * increments reference counts regardless of device state.
3460 	 */
3461 	mutex_lock(&ap->scsi_host->scan_mutex);
3462 	spin_lock_irqsave(ap->lock, flags);
3463 
3464 	/* clearing dev->sdev is protected by host lock */
3465 	sdev = dev->sdev;
3466 	dev->sdev = NULL;
3467 
3468 	if (sdev) {
3469 		/* If user initiated unplug races with us, sdev can go
3470 		 * away underneath us after the host lock and
3471 		 * scan_mutex are released.  Hold onto it.
3472 		 */
3473 		if (scsi_device_get(sdev) == 0) {
3474 			/* The following ensures the attached sdev is
3475 			 * offline on return from ata_scsi_offline_dev()
3476 			 * regardless it wins or loses the race
3477 			 * against this function.
3478 			 */
3479 			scsi_device_set_state(sdev, SDEV_OFFLINE);
3480 		} else {
3481 			WARN_ON(1);
3482 			sdev = NULL;
3483 		}
3484 	}
3485 
3486 	spin_unlock_irqrestore(ap->lock, flags);
3487 	mutex_unlock(&ap->scsi_host->scan_mutex);
3488 
3489 	if (sdev) {
3490 		ata_dev_printk(dev, KERN_INFO, "detaching (SCSI %s)\n",
3491 			       dev_name(&sdev->sdev_gendev));
3492 
3493 		scsi_remove_device(sdev);
3494 		scsi_device_put(sdev);
3495 	}
3496 }
3497 
3498 static void ata_scsi_handle_link_detach(struct ata_link *link)
3499 {
3500 	struct ata_port *ap = link->ap;
3501 	struct ata_device *dev;
3502 
3503 	ata_for_each_dev(dev, link, ALL) {
3504 		unsigned long flags;
3505 
3506 		if (!(dev->flags & ATA_DFLAG_DETACHED))
3507 			continue;
3508 
3509 		spin_lock_irqsave(ap->lock, flags);
3510 		dev->flags &= ~ATA_DFLAG_DETACHED;
3511 		spin_unlock_irqrestore(ap->lock, flags);
3512 
3513 		ata_scsi_remove_dev(dev);
3514 	}
3515 }
3516 
3517 /**
3518  *	ata_scsi_media_change_notify - send media change event
3519  *	@dev: Pointer to the disk device with media change event
3520  *
3521  *	Tell the block layer to send a media change notification
3522  *	event.
3523  *
3524  * 	LOCKING:
3525  * 	spin_lock_irqsave(host lock)
3526  */
3527 void ata_scsi_media_change_notify(struct ata_device *dev)
3528 {
3529 	if (dev->sdev)
3530 		sdev_evt_send_simple(dev->sdev, SDEV_EVT_MEDIA_CHANGE,
3531 				     GFP_ATOMIC);
3532 }
3533 
3534 /**
3535  *	ata_scsi_hotplug - SCSI part of hotplug
3536  *	@work: Pointer to ATA port to perform SCSI hotplug on
3537  *
3538  *	Perform SCSI part of hotplug.  It's executed from a separate
3539  *	workqueue after EH completes.  This is necessary because SCSI
3540  *	hot plugging requires working EH and hot unplugging is
3541  *	synchronized with hot plugging with a mutex.
3542  *
3543  *	LOCKING:
3544  *	Kernel thread context (may sleep).
3545  */
3546 void ata_scsi_hotplug(struct work_struct *work)
3547 {
3548 	struct ata_port *ap =
3549 		container_of(work, struct ata_port, hotplug_task.work);
3550 	int i;
3551 
3552 	if (ap->pflags & ATA_PFLAG_UNLOADING) {
3553 		DPRINTK("ENTER/EXIT - unloading\n");
3554 		return;
3555 	}
3556 
3557 	DPRINTK("ENTER\n");
3558 
3559 	/* Unplug detached devices.  We cannot use link iterator here
3560 	 * because PMP links have to be scanned even if PMP is
3561 	 * currently not attached.  Iterate manually.
3562 	 */
3563 	ata_scsi_handle_link_detach(&ap->link);
3564 	if (ap->pmp_link)
3565 		for (i = 0; i < SATA_PMP_MAX_PORTS; i++)
3566 			ata_scsi_handle_link_detach(&ap->pmp_link[i]);
3567 
3568 	/* scan for new ones */
3569 	ata_scsi_scan_host(ap, 0);
3570 
3571 	DPRINTK("EXIT\n");
3572 }
3573 
3574 /**
3575  *	ata_scsi_user_scan - indication for user-initiated bus scan
3576  *	@shost: SCSI host to scan
3577  *	@channel: Channel to scan
3578  *	@id: ID to scan
3579  *	@lun: LUN to scan
3580  *
3581  *	This function is called when user explicitly requests bus
3582  *	scan.  Set probe pending flag and invoke EH.
3583  *
3584  *	LOCKING:
3585  *	SCSI layer (we don't care)
3586  *
3587  *	RETURNS:
3588  *	Zero.
3589  */
3590 static int ata_scsi_user_scan(struct Scsi_Host *shost, unsigned int channel,
3591 			      unsigned int id, unsigned int lun)
3592 {
3593 	struct ata_port *ap = ata_shost_to_port(shost);
3594 	unsigned long flags;
3595 	int devno, rc = 0;
3596 
3597 	if (!ap->ops->error_handler)
3598 		return -EOPNOTSUPP;
3599 
3600 	if (lun != SCAN_WILD_CARD && lun)
3601 		return -EINVAL;
3602 
3603 	if (!sata_pmp_attached(ap)) {
3604 		if (channel != SCAN_WILD_CARD && channel)
3605 			return -EINVAL;
3606 		devno = id;
3607 	} else {
3608 		if (id != SCAN_WILD_CARD && id)
3609 			return -EINVAL;
3610 		devno = channel;
3611 	}
3612 
3613 	spin_lock_irqsave(ap->lock, flags);
3614 
3615 	if (devno == SCAN_WILD_CARD) {
3616 		struct ata_link *link;
3617 
3618 		ata_for_each_link(link, ap, EDGE) {
3619 			struct ata_eh_info *ehi = &link->eh_info;
3620 			ehi->probe_mask |= ATA_ALL_DEVICES;
3621 			ehi->action |= ATA_EH_RESET;
3622 		}
3623 	} else {
3624 		struct ata_device *dev = ata_find_dev(ap, devno);
3625 
3626 		if (dev) {
3627 			struct ata_eh_info *ehi = &dev->link->eh_info;
3628 			ehi->probe_mask |= 1 << dev->devno;
3629 			ehi->action |= ATA_EH_RESET;
3630 		} else
3631 			rc = -EINVAL;
3632 	}
3633 
3634 	if (rc == 0) {
3635 		ata_port_schedule_eh(ap);
3636 		spin_unlock_irqrestore(ap->lock, flags);
3637 		ata_port_wait_eh(ap);
3638 	} else
3639 		spin_unlock_irqrestore(ap->lock, flags);
3640 
3641 	return rc;
3642 }
3643 
3644 /**
3645  *	ata_scsi_dev_rescan - initiate scsi_rescan_device()
3646  *	@work: Pointer to ATA port to perform scsi_rescan_device()
3647  *
3648  *	After ATA pass thru (SAT) commands are executed successfully,
3649  *	libata need to propagate the changes to SCSI layer.  This
3650  *	function must be executed from ata_aux_wq such that sdev
3651  *	attach/detach don't race with rescan.
3652  *
3653  *	LOCKING:
3654  *	Kernel thread context (may sleep).
3655  */
3656 void ata_scsi_dev_rescan(struct work_struct *work)
3657 {
3658 	struct ata_port *ap =
3659 		container_of(work, struct ata_port, scsi_rescan_task);
3660 	struct ata_link *link;
3661 	struct ata_device *dev;
3662 	unsigned long flags;
3663 
3664 	spin_lock_irqsave(ap->lock, flags);
3665 
3666 	ata_for_each_link(link, ap, EDGE) {
3667 		ata_for_each_dev(dev, link, ENABLED) {
3668 			struct scsi_device *sdev = dev->sdev;
3669 
3670 			if (!sdev)
3671 				continue;
3672 			if (scsi_device_get(sdev))
3673 				continue;
3674 
3675 			spin_unlock_irqrestore(ap->lock, flags);
3676 			scsi_rescan_device(&(sdev->sdev_gendev));
3677 			scsi_device_put(sdev);
3678 			spin_lock_irqsave(ap->lock, flags);
3679 		}
3680 	}
3681 
3682 	spin_unlock_irqrestore(ap->lock, flags);
3683 }
3684 
3685 /**
3686  *	ata_sas_port_alloc - Allocate port for a SAS attached SATA device
3687  *	@host: ATA host container for all SAS ports
3688  *	@port_info: Information from low-level host driver
3689  *	@shost: SCSI host that the scsi device is attached to
3690  *
3691  *	LOCKING:
3692  *	PCI/etc. bus probe sem.
3693  *
3694  *	RETURNS:
3695  *	ata_port pointer on success / NULL on failure.
3696  */
3697 
3698 struct ata_port *ata_sas_port_alloc(struct ata_host *host,
3699 				    struct ata_port_info *port_info,
3700 				    struct Scsi_Host *shost)
3701 {
3702 	struct ata_port *ap;
3703 
3704 	ap = ata_port_alloc(host);
3705 	if (!ap)
3706 		return NULL;
3707 
3708 	ap->port_no = 0;
3709 	ap->lock = shost->host_lock;
3710 	ap->pio_mask = port_info->pio_mask;
3711 	ap->mwdma_mask = port_info->mwdma_mask;
3712 	ap->udma_mask = port_info->udma_mask;
3713 	ap->flags |= port_info->flags;
3714 	ap->ops = port_info->port_ops;
3715 	ap->cbl = ATA_CBL_SATA;
3716 
3717 	return ap;
3718 }
3719 EXPORT_SYMBOL_GPL(ata_sas_port_alloc);
3720 
3721 /**
3722  *	ata_sas_port_start - Set port up for dma.
3723  *	@ap: Port to initialize
3724  *
3725  *	Called just after data structures for each port are
3726  *	initialized.
3727  *
3728  *	May be used as the port_start() entry in ata_port_operations.
3729  *
3730  *	LOCKING:
3731  *	Inherited from caller.
3732  */
3733 int ata_sas_port_start(struct ata_port *ap)
3734 {
3735 	return 0;
3736 }
3737 EXPORT_SYMBOL_GPL(ata_sas_port_start);
3738 
3739 /**
3740  *	ata_port_stop - Undo ata_sas_port_start()
3741  *	@ap: Port to shut down
3742  *
3743  *	May be used as the port_stop() entry in ata_port_operations.
3744  *
3745  *	LOCKING:
3746  *	Inherited from caller.
3747  */
3748 
3749 void ata_sas_port_stop(struct ata_port *ap)
3750 {
3751 }
3752 EXPORT_SYMBOL_GPL(ata_sas_port_stop);
3753 
3754 /**
3755  *	ata_sas_port_init - Initialize a SATA device
3756  *	@ap: SATA port to initialize
3757  *
3758  *	LOCKING:
3759  *	PCI/etc. bus probe sem.
3760  *
3761  *	RETURNS:
3762  *	Zero on success, non-zero on error.
3763  */
3764 
3765 int ata_sas_port_init(struct ata_port *ap)
3766 {
3767 	int rc = ap->ops->port_start(ap);
3768 
3769 	if (!rc) {
3770 		ap->print_id = ata_print_id++;
3771 		rc = ata_bus_probe(ap);
3772 	}
3773 
3774 	return rc;
3775 }
3776 EXPORT_SYMBOL_GPL(ata_sas_port_init);
3777 
3778 /**
3779  *	ata_sas_port_destroy - Destroy a SATA port allocated by ata_sas_port_alloc
3780  *	@ap: SATA port to destroy
3781  *
3782  */
3783 
3784 void ata_sas_port_destroy(struct ata_port *ap)
3785 {
3786 	if (ap->ops->port_stop)
3787 		ap->ops->port_stop(ap);
3788 	kfree(ap);
3789 }
3790 EXPORT_SYMBOL_GPL(ata_sas_port_destroy);
3791 
3792 /**
3793  *	ata_sas_slave_configure - Default slave_config routine for libata devices
3794  *	@sdev: SCSI device to configure
3795  *	@ap: ATA port to which SCSI device is attached
3796  *
3797  *	RETURNS:
3798  *	Zero.
3799  */
3800 
3801 int ata_sas_slave_configure(struct scsi_device *sdev, struct ata_port *ap)
3802 {
3803 	ata_scsi_sdev_config(sdev);
3804 	ata_scsi_dev_config(sdev, ap->link.device);
3805 	return 0;
3806 }
3807 EXPORT_SYMBOL_GPL(ata_sas_slave_configure);
3808 
3809 /**
3810  *	ata_sas_queuecmd - Issue SCSI cdb to libata-managed device
3811  *	@cmd: SCSI command to be sent
3812  *	@done: Completion function, called when command is complete
3813  *	@ap:	ATA port to which the command is being sent
3814  *
3815  *	RETURNS:
3816  *	Return value from __ata_scsi_queuecmd() if @cmd can be queued,
3817  *	0 otherwise.
3818  */
3819 
3820 int ata_sas_queuecmd(struct scsi_cmnd *cmd, void (*done)(struct scsi_cmnd *),
3821 		     struct ata_port *ap)
3822 {
3823 	int rc = 0;
3824 
3825 	ata_scsi_dump_cdb(ap, cmd);
3826 
3827 	if (likely(ata_dev_enabled(ap->link.device)))
3828 		rc = __ata_scsi_queuecmd(cmd, done, ap->link.device);
3829 	else {
3830 		cmd->result = (DID_BAD_TARGET << 16);
3831 		done(cmd);
3832 	}
3833 	return rc;
3834 }
3835 EXPORT_SYMBOL_GPL(ata_sas_queuecmd);
3836