xref: /linux/drivers/ata/libata-scsi.c (revision b3b77c8caef1750ebeea1054e39e358550ea9f55)
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/slab.h>
37 #include <linux/kernel.h>
38 #include <linux/blkdev.h>
39 #include <linux/spinlock.h>
40 #include <scsi/scsi.h>
41 #include <scsi/scsi_host.h>
42 #include <scsi/scsi_cmnd.h>
43 #include <scsi/scsi_eh.h>
44 #include <scsi/scsi_device.h>
45 #include <scsi/scsi_tcq.h>
46 #include <scsi/scsi_transport.h>
47 #include <linux/libata.h>
48 #include <linux/hdreg.h>
49 #include <linux/uaccess.h>
50 #include <linux/suspend.h>
51 #include <asm/unaligned.h>
52 
53 #include "libata.h"
54 
55 #define SECTOR_SIZE		512
56 #define ATA_SCSI_RBUF_SIZE	4096
57 
58 static DEFINE_SPINLOCK(ata_scsi_rbuf_lock);
59 static u8 ata_scsi_rbuf[ATA_SCSI_RBUF_SIZE];
60 
61 typedef unsigned int (*ata_xlat_func_t)(struct ata_queued_cmd *qc);
62 
63 static struct ata_device *__ata_scsi_find_dev(struct ata_port *ap,
64 					const struct scsi_device *scsidev);
65 static struct ata_device *ata_scsi_find_dev(struct ata_port *ap,
66 					    const struct scsi_device *scsidev);
67 static int ata_scsi_user_scan(struct Scsi_Host *shost, unsigned int channel,
68 			      unsigned int id, unsigned int lun);
69 
70 
71 #define RW_RECOVERY_MPAGE 0x1
72 #define RW_RECOVERY_MPAGE_LEN 12
73 #define CACHE_MPAGE 0x8
74 #define CACHE_MPAGE_LEN 20
75 #define CONTROL_MPAGE 0xa
76 #define CONTROL_MPAGE_LEN 12
77 #define ALL_MPAGES 0x3f
78 #define ALL_SUB_MPAGES 0xff
79 
80 
81 static const u8 def_rw_recovery_mpage[RW_RECOVERY_MPAGE_LEN] = {
82 	RW_RECOVERY_MPAGE,
83 	RW_RECOVERY_MPAGE_LEN - 2,
84 	(1 << 7),	/* AWRE */
85 	0,		/* read retry count */
86 	0, 0, 0, 0,
87 	0,		/* write retry count */
88 	0, 0, 0
89 };
90 
91 static const u8 def_cache_mpage[CACHE_MPAGE_LEN] = {
92 	CACHE_MPAGE,
93 	CACHE_MPAGE_LEN - 2,
94 	0,		/* contains WCE, needs to be 0 for logic */
95 	0, 0, 0, 0, 0, 0, 0, 0, 0,
96 	0,		/* contains DRA, needs to be 0 for logic */
97 	0, 0, 0, 0, 0, 0, 0
98 };
99 
100 static const u8 def_control_mpage[CONTROL_MPAGE_LEN] = {
101 	CONTROL_MPAGE,
102 	CONTROL_MPAGE_LEN - 2,
103 	2,	/* DSENSE=0, GLTSD=1 */
104 	0,	/* [QAM+QERR may be 1, see 05-359r1] */
105 	0, 0, 0, 0, 0xff, 0xff,
106 	0, 30	/* extended self test time, see 05-359r1 */
107 };
108 
109 /*
110  * libata transport template.  libata doesn't do real transport stuff.
111  * It just needs the eh_timed_out hook.
112  */
113 static struct scsi_transport_template ata_scsi_transport_template = {
114 	.eh_strategy_handler	= ata_scsi_error,
115 	.eh_timed_out		= ata_scsi_timed_out,
116 	.user_scan		= ata_scsi_user_scan,
117 };
118 
119 
120 static const struct {
121 	enum link_pm	value;
122 	const char	*name;
123 } link_pm_policy[] = {
124 	{ NOT_AVAILABLE, "max_performance" },
125 	{ MIN_POWER, "min_power" },
126 	{ MAX_PERFORMANCE, "max_performance" },
127 	{ MEDIUM_POWER, "medium_power" },
128 };
129 
130 static const char *ata_scsi_lpm_get(enum link_pm policy)
131 {
132 	int i;
133 
134 	for (i = 0; i < ARRAY_SIZE(link_pm_policy); i++)
135 		if (link_pm_policy[i].value == policy)
136 			return link_pm_policy[i].name;
137 
138 	return NULL;
139 }
140 
141 static ssize_t ata_scsi_lpm_put(struct device *dev,
142 				struct device_attribute *attr,
143 				const char *buf, size_t count)
144 {
145 	struct Scsi_Host *shost = class_to_shost(dev);
146 	struct ata_port *ap = ata_shost_to_port(shost);
147 	enum link_pm policy = 0;
148 	int i;
149 
150 	/*
151 	 * we are skipping array location 0 on purpose - this
152 	 * is because a value of NOT_AVAILABLE is displayed
153 	 * to the user as max_performance, but when the user
154 	 * writes "max_performance", they actually want the
155 	 * value to match MAX_PERFORMANCE.
156 	 */
157 	for (i = 1; i < ARRAY_SIZE(link_pm_policy); i++) {
158 		const int len = strlen(link_pm_policy[i].name);
159 		if (strncmp(link_pm_policy[i].name, buf, len) == 0) {
160 			policy = link_pm_policy[i].value;
161 			break;
162 		}
163 	}
164 	if (!policy)
165 		return -EINVAL;
166 
167 	ata_lpm_schedule(ap, policy);
168 	return count;
169 }
170 
171 static ssize_t
172 ata_scsi_lpm_show(struct device *dev, struct device_attribute *attr, char *buf)
173 {
174 	struct Scsi_Host *shost = class_to_shost(dev);
175 	struct ata_port *ap = ata_shost_to_port(shost);
176 	const char *policy =
177 		ata_scsi_lpm_get(ap->pm_policy);
178 
179 	if (!policy)
180 		return -EINVAL;
181 
182 	return snprintf(buf, 23, "%s\n", policy);
183 }
184 DEVICE_ATTR(link_power_management_policy, S_IRUGO | S_IWUSR,
185 		ata_scsi_lpm_show, ata_scsi_lpm_put);
186 EXPORT_SYMBOL_GPL(dev_attr_link_power_management_policy);
187 
188 static ssize_t ata_scsi_park_show(struct device *device,
189 				  struct device_attribute *attr, char *buf)
190 {
191 	struct scsi_device *sdev = to_scsi_device(device);
192 	struct ata_port *ap;
193 	struct ata_link *link;
194 	struct ata_device *dev;
195 	unsigned long flags, now;
196 	unsigned int uninitialized_var(msecs);
197 	int rc = 0;
198 
199 	ap = ata_shost_to_port(sdev->host);
200 
201 	spin_lock_irqsave(ap->lock, flags);
202 	dev = ata_scsi_find_dev(ap, sdev);
203 	if (!dev) {
204 		rc = -ENODEV;
205 		goto unlock;
206 	}
207 	if (dev->flags & ATA_DFLAG_NO_UNLOAD) {
208 		rc = -EOPNOTSUPP;
209 		goto unlock;
210 	}
211 
212 	link = dev->link;
213 	now = jiffies;
214 	if (ap->pflags & ATA_PFLAG_EH_IN_PROGRESS &&
215 	    link->eh_context.unloaded_mask & (1 << dev->devno) &&
216 	    time_after(dev->unpark_deadline, now))
217 		msecs = jiffies_to_msecs(dev->unpark_deadline - now);
218 	else
219 		msecs = 0;
220 
221 unlock:
222 	spin_unlock_irq(ap->lock);
223 
224 	return rc ? rc : snprintf(buf, 20, "%u\n", msecs);
225 }
226 
227 static ssize_t ata_scsi_park_store(struct device *device,
228 				   struct device_attribute *attr,
229 				   const char *buf, size_t len)
230 {
231 	struct scsi_device *sdev = to_scsi_device(device);
232 	struct ata_port *ap;
233 	struct ata_device *dev;
234 	long int input;
235 	unsigned long flags;
236 	int rc;
237 
238 	rc = strict_strtol(buf, 10, &input);
239 	if (rc || input < -2)
240 		return -EINVAL;
241 	if (input > ATA_TMOUT_MAX_PARK) {
242 		rc = -EOVERFLOW;
243 		input = ATA_TMOUT_MAX_PARK;
244 	}
245 
246 	ap = ata_shost_to_port(sdev->host);
247 
248 	spin_lock_irqsave(ap->lock, flags);
249 	dev = ata_scsi_find_dev(ap, sdev);
250 	if (unlikely(!dev)) {
251 		rc = -ENODEV;
252 		goto unlock;
253 	}
254 	if (dev->class != ATA_DEV_ATA) {
255 		rc = -EOPNOTSUPP;
256 		goto unlock;
257 	}
258 
259 	if (input >= 0) {
260 		if (dev->flags & ATA_DFLAG_NO_UNLOAD) {
261 			rc = -EOPNOTSUPP;
262 			goto unlock;
263 		}
264 
265 		dev->unpark_deadline = ata_deadline(jiffies, input);
266 		dev->link->eh_info.dev_action[dev->devno] |= ATA_EH_PARK;
267 		ata_port_schedule_eh(ap);
268 		complete(&ap->park_req_pending);
269 	} else {
270 		switch (input) {
271 		case -1:
272 			dev->flags &= ~ATA_DFLAG_NO_UNLOAD;
273 			break;
274 		case -2:
275 			dev->flags |= ATA_DFLAG_NO_UNLOAD;
276 			break;
277 		}
278 	}
279 unlock:
280 	spin_unlock_irqrestore(ap->lock, flags);
281 
282 	return rc ? rc : len;
283 }
284 DEVICE_ATTR(unload_heads, S_IRUGO | S_IWUSR,
285 	    ata_scsi_park_show, ata_scsi_park_store);
286 EXPORT_SYMBOL_GPL(dev_attr_unload_heads);
287 
288 static void ata_scsi_set_sense(struct scsi_cmnd *cmd, u8 sk, u8 asc, u8 ascq)
289 {
290 	cmd->result = (DRIVER_SENSE << 24) | SAM_STAT_CHECK_CONDITION;
291 
292 	scsi_build_sense_buffer(0, cmd->sense_buffer, sk, asc, ascq);
293 }
294 
295 static ssize_t
296 ata_scsi_em_message_store(struct device *dev, struct device_attribute *attr,
297 			  const char *buf, size_t count)
298 {
299 	struct Scsi_Host *shost = class_to_shost(dev);
300 	struct ata_port *ap = ata_shost_to_port(shost);
301 	if (ap->ops->em_store && (ap->flags & ATA_FLAG_EM))
302 		return ap->ops->em_store(ap, buf, count);
303 	return -EINVAL;
304 }
305 
306 static ssize_t
307 ata_scsi_em_message_show(struct device *dev, struct device_attribute *attr,
308 			 char *buf)
309 {
310 	struct Scsi_Host *shost = class_to_shost(dev);
311 	struct ata_port *ap = ata_shost_to_port(shost);
312 
313 	if (ap->ops->em_show && (ap->flags & ATA_FLAG_EM))
314 		return ap->ops->em_show(ap, buf);
315 	return -EINVAL;
316 }
317 DEVICE_ATTR(em_message, S_IRUGO | S_IWUSR,
318 		ata_scsi_em_message_show, ata_scsi_em_message_store);
319 EXPORT_SYMBOL_GPL(dev_attr_em_message);
320 
321 static ssize_t
322 ata_scsi_em_message_type_show(struct device *dev, struct device_attribute *attr,
323 			      char *buf)
324 {
325 	struct Scsi_Host *shost = class_to_shost(dev);
326 	struct ata_port *ap = ata_shost_to_port(shost);
327 
328 	return snprintf(buf, 23, "%d\n", ap->em_message_type);
329 }
330 DEVICE_ATTR(em_message_type, S_IRUGO,
331 		  ata_scsi_em_message_type_show, NULL);
332 EXPORT_SYMBOL_GPL(dev_attr_em_message_type);
333 
334 static ssize_t
335 ata_scsi_activity_show(struct device *dev, struct device_attribute *attr,
336 		char *buf)
337 {
338 	struct scsi_device *sdev = to_scsi_device(dev);
339 	struct ata_port *ap = ata_shost_to_port(sdev->host);
340 	struct ata_device *atadev = ata_scsi_find_dev(ap, sdev);
341 
342 	if (ap->ops->sw_activity_show && (ap->flags & ATA_FLAG_SW_ACTIVITY))
343 		return ap->ops->sw_activity_show(atadev, buf);
344 	return -EINVAL;
345 }
346 
347 static ssize_t
348 ata_scsi_activity_store(struct device *dev, struct device_attribute *attr,
349 	const char *buf, size_t count)
350 {
351 	struct scsi_device *sdev = to_scsi_device(dev);
352 	struct ata_port *ap = ata_shost_to_port(sdev->host);
353 	struct ata_device *atadev = ata_scsi_find_dev(ap, sdev);
354 	enum sw_activity val;
355 	int rc;
356 
357 	if (ap->ops->sw_activity_store && (ap->flags & ATA_FLAG_SW_ACTIVITY)) {
358 		val = simple_strtoul(buf, NULL, 0);
359 		switch (val) {
360 		case OFF: case BLINK_ON: case BLINK_OFF:
361 			rc = ap->ops->sw_activity_store(atadev, val);
362 			if (!rc)
363 				return count;
364 			else
365 				return rc;
366 		}
367 	}
368 	return -EINVAL;
369 }
370 DEVICE_ATTR(sw_activity, S_IWUSR | S_IRUGO, ata_scsi_activity_show,
371 			ata_scsi_activity_store);
372 EXPORT_SYMBOL_GPL(dev_attr_sw_activity);
373 
374 struct device_attribute *ata_common_sdev_attrs[] = {
375 	&dev_attr_unload_heads,
376 	NULL
377 };
378 EXPORT_SYMBOL_GPL(ata_common_sdev_attrs);
379 
380 static void ata_scsi_invalid_field(struct scsi_cmnd *cmd,
381 				   void (*done)(struct scsi_cmnd *))
382 {
383 	ata_scsi_set_sense(cmd, ILLEGAL_REQUEST, 0x24, 0x0);
384 	/* "Invalid field in cbd" */
385 	done(cmd);
386 }
387 
388 /**
389  *	ata_std_bios_param - generic bios head/sector/cylinder calculator used by sd.
390  *	@sdev: SCSI device for which BIOS geometry is to be determined
391  *	@bdev: block device associated with @sdev
392  *	@capacity: capacity of SCSI device
393  *	@geom: location to which geometry will be output
394  *
395  *	Generic bios head/sector/cylinder calculator
396  *	used by sd. Most BIOSes nowadays expect a XXX/255/16  (CHS)
397  *	mapping. Some situations may arise where the disk is not
398  *	bootable if this is not used.
399  *
400  *	LOCKING:
401  *	Defined by the SCSI layer.  We don't really care.
402  *
403  *	RETURNS:
404  *	Zero.
405  */
406 int ata_std_bios_param(struct scsi_device *sdev, struct block_device *bdev,
407 		       sector_t capacity, int geom[])
408 {
409 	geom[0] = 255;
410 	geom[1] = 63;
411 	sector_div(capacity, 255*63);
412 	geom[2] = capacity;
413 
414 	return 0;
415 }
416 
417 /**
418  *	ata_get_identity - Handler for HDIO_GET_IDENTITY ioctl
419  *	@ap: target port
420  *	@sdev: SCSI device to get identify data for
421  *	@arg: User buffer area for identify data
422  *
423  *	LOCKING:
424  *	Defined by the SCSI layer.  We don't really care.
425  *
426  *	RETURNS:
427  *	Zero on success, negative errno on error.
428  */
429 static int ata_get_identity(struct ata_port *ap, struct scsi_device *sdev,
430 			    void __user *arg)
431 {
432 	struct ata_device *dev = ata_scsi_find_dev(ap, sdev);
433 	u16 __user *dst = arg;
434 	char buf[40];
435 
436 	if (!dev)
437 		return -ENOMSG;
438 
439 	if (copy_to_user(dst, dev->id, ATA_ID_WORDS * sizeof(u16)))
440 		return -EFAULT;
441 
442 	ata_id_string(dev->id, buf, ATA_ID_PROD, ATA_ID_PROD_LEN);
443 	if (copy_to_user(dst + ATA_ID_PROD, buf, ATA_ID_PROD_LEN))
444 		return -EFAULT;
445 
446 	ata_id_string(dev->id, buf, ATA_ID_FW_REV, ATA_ID_FW_REV_LEN);
447 	if (copy_to_user(dst + ATA_ID_FW_REV, buf, ATA_ID_FW_REV_LEN))
448 		return -EFAULT;
449 
450 	ata_id_string(dev->id, buf, ATA_ID_SERNO, ATA_ID_SERNO_LEN);
451 	if (copy_to_user(dst + ATA_ID_SERNO, buf, ATA_ID_SERNO_LEN))
452 		return -EFAULT;
453 
454 	return 0;
455 }
456 
457 /**
458  *	ata_cmd_ioctl - Handler for HDIO_DRIVE_CMD ioctl
459  *	@scsidev: Device to which we are issuing command
460  *	@arg: User provided data for issuing command
461  *
462  *	LOCKING:
463  *	Defined by the SCSI layer.  We don't really care.
464  *
465  *	RETURNS:
466  *	Zero on success, negative errno on error.
467  */
468 int ata_cmd_ioctl(struct scsi_device *scsidev, void __user *arg)
469 {
470 	int rc = 0;
471 	u8 scsi_cmd[MAX_COMMAND_SIZE];
472 	u8 args[4], *argbuf = NULL, *sensebuf = NULL;
473 	int argsize = 0;
474 	enum dma_data_direction data_dir;
475 	int cmd_result;
476 
477 	if (arg == NULL)
478 		return -EINVAL;
479 
480 	if (copy_from_user(args, arg, sizeof(args)))
481 		return -EFAULT;
482 
483 	sensebuf = kzalloc(SCSI_SENSE_BUFFERSIZE, GFP_NOIO);
484 	if (!sensebuf)
485 		return -ENOMEM;
486 
487 	memset(scsi_cmd, 0, sizeof(scsi_cmd));
488 
489 	if (args[3]) {
490 		argsize = SECTOR_SIZE * args[3];
491 		argbuf = kmalloc(argsize, GFP_KERNEL);
492 		if (argbuf == NULL) {
493 			rc = -ENOMEM;
494 			goto error;
495 		}
496 
497 		scsi_cmd[1]  = (4 << 1); /* PIO Data-in */
498 		scsi_cmd[2]  = 0x0e;     /* no off.line or cc, read from dev,
499 					    block count in sector count field */
500 		data_dir = DMA_FROM_DEVICE;
501 	} else {
502 		scsi_cmd[1]  = (3 << 1); /* Non-data */
503 		scsi_cmd[2]  = 0x20;     /* cc but no off.line or data xfer */
504 		data_dir = DMA_NONE;
505 	}
506 
507 	scsi_cmd[0] = ATA_16;
508 
509 	scsi_cmd[4] = args[2];
510 	if (args[0] == ATA_CMD_SMART) { /* hack -- ide driver does this too */
511 		scsi_cmd[6]  = args[3];
512 		scsi_cmd[8]  = args[1];
513 		scsi_cmd[10] = 0x4f;
514 		scsi_cmd[12] = 0xc2;
515 	} else {
516 		scsi_cmd[6]  = args[1];
517 	}
518 	scsi_cmd[14] = args[0];
519 
520 	/* Good values for timeout and retries?  Values below
521 	   from scsi_ioctl_send_command() for default case... */
522 	cmd_result = scsi_execute(scsidev, scsi_cmd, data_dir, argbuf, argsize,
523 				  sensebuf, (10*HZ), 5, 0, NULL);
524 
525 	if (driver_byte(cmd_result) == DRIVER_SENSE) {/* sense data available */
526 		u8 *desc = sensebuf + 8;
527 		cmd_result &= ~(0xFF<<24); /* DRIVER_SENSE is not an error */
528 
529 		/* If we set cc then ATA pass-through will cause a
530 		 * check condition even if no error. Filter that. */
531 		if (cmd_result & SAM_STAT_CHECK_CONDITION) {
532 			struct scsi_sense_hdr sshdr;
533 			scsi_normalize_sense(sensebuf, SCSI_SENSE_BUFFERSIZE,
534 					     &sshdr);
535 			if (sshdr.sense_key == 0 &&
536 			    sshdr.asc == 0 && sshdr.ascq == 0)
537 				cmd_result &= ~SAM_STAT_CHECK_CONDITION;
538 		}
539 
540 		/* Send userspace a few ATA registers (same as drivers/ide) */
541 		if (sensebuf[0] == 0x72 &&	/* format is "descriptor" */
542 		    desc[0] == 0x09) {		/* code is "ATA Descriptor" */
543 			args[0] = desc[13];	/* status */
544 			args[1] = desc[3];	/* error */
545 			args[2] = desc[5];	/* sector count (0:7) */
546 			if (copy_to_user(arg, args, sizeof(args)))
547 				rc = -EFAULT;
548 		}
549 	}
550 
551 
552 	if (cmd_result) {
553 		rc = -EIO;
554 		goto error;
555 	}
556 
557 	if ((argbuf)
558 	 && copy_to_user(arg + sizeof(args), argbuf, argsize))
559 		rc = -EFAULT;
560 error:
561 	kfree(sensebuf);
562 	kfree(argbuf);
563 	return rc;
564 }
565 
566 /**
567  *	ata_task_ioctl - Handler for HDIO_DRIVE_TASK ioctl
568  *	@scsidev: Device to which we are issuing command
569  *	@arg: User provided data for issuing command
570  *
571  *	LOCKING:
572  *	Defined by the SCSI layer.  We don't really care.
573  *
574  *	RETURNS:
575  *	Zero on success, negative errno on error.
576  */
577 int ata_task_ioctl(struct scsi_device *scsidev, void __user *arg)
578 {
579 	int rc = 0;
580 	u8 scsi_cmd[MAX_COMMAND_SIZE];
581 	u8 args[7], *sensebuf = NULL;
582 	int cmd_result;
583 
584 	if (arg == NULL)
585 		return -EINVAL;
586 
587 	if (copy_from_user(args, arg, sizeof(args)))
588 		return -EFAULT;
589 
590 	sensebuf = kzalloc(SCSI_SENSE_BUFFERSIZE, GFP_NOIO);
591 	if (!sensebuf)
592 		return -ENOMEM;
593 
594 	memset(scsi_cmd, 0, sizeof(scsi_cmd));
595 	scsi_cmd[0]  = ATA_16;
596 	scsi_cmd[1]  = (3 << 1); /* Non-data */
597 	scsi_cmd[2]  = 0x20;     /* cc but no off.line or data xfer */
598 	scsi_cmd[4]  = args[1];
599 	scsi_cmd[6]  = args[2];
600 	scsi_cmd[8]  = args[3];
601 	scsi_cmd[10] = args[4];
602 	scsi_cmd[12] = args[5];
603 	scsi_cmd[13] = args[6] & 0x4f;
604 	scsi_cmd[14] = args[0];
605 
606 	/* Good values for timeout and retries?  Values below
607 	   from scsi_ioctl_send_command() for default case... */
608 	cmd_result = scsi_execute(scsidev, scsi_cmd, DMA_NONE, NULL, 0,
609 				sensebuf, (10*HZ), 5, 0, NULL);
610 
611 	if (driver_byte(cmd_result) == DRIVER_SENSE) {/* sense data available */
612 		u8 *desc = sensebuf + 8;
613 		cmd_result &= ~(0xFF<<24); /* DRIVER_SENSE is not an error */
614 
615 		/* If we set cc then ATA pass-through will cause a
616 		 * check condition even if no error. Filter that. */
617 		if (cmd_result & SAM_STAT_CHECK_CONDITION) {
618 			struct scsi_sense_hdr sshdr;
619 			scsi_normalize_sense(sensebuf, SCSI_SENSE_BUFFERSIZE,
620 						&sshdr);
621 			if (sshdr.sense_key == 0 &&
622 				sshdr.asc == 0 && sshdr.ascq == 0)
623 				cmd_result &= ~SAM_STAT_CHECK_CONDITION;
624 		}
625 
626 		/* Send userspace ATA registers */
627 		if (sensebuf[0] == 0x72 &&	/* format is "descriptor" */
628 				desc[0] == 0x09) {/* code is "ATA Descriptor" */
629 			args[0] = desc[13];	/* status */
630 			args[1] = desc[3];	/* error */
631 			args[2] = desc[5];	/* sector count (0:7) */
632 			args[3] = desc[7];	/* lbal */
633 			args[4] = desc[9];	/* lbam */
634 			args[5] = desc[11];	/* lbah */
635 			args[6] = desc[12];	/* select */
636 			if (copy_to_user(arg, args, sizeof(args)))
637 				rc = -EFAULT;
638 		}
639 	}
640 
641 	if (cmd_result) {
642 		rc = -EIO;
643 		goto error;
644 	}
645 
646  error:
647 	kfree(sensebuf);
648 	return rc;
649 }
650 
651 static int ata_ioc32(struct ata_port *ap)
652 {
653 	if (ap->flags & ATA_FLAG_PIO_DMA)
654 		return 1;
655 	if (ap->pflags & ATA_PFLAG_PIO32)
656 		return 1;
657 	return 0;
658 }
659 
660 int ata_sas_scsi_ioctl(struct ata_port *ap, struct scsi_device *scsidev,
661 		     int cmd, void __user *arg)
662 {
663 	int val = -EINVAL, rc = -EINVAL;
664 	unsigned long flags;
665 
666 	switch (cmd) {
667 	case ATA_IOC_GET_IO32:
668 		spin_lock_irqsave(ap->lock, flags);
669 		val = ata_ioc32(ap);
670 		spin_unlock_irqrestore(ap->lock, flags);
671 		if (copy_to_user(arg, &val, 1))
672 			return -EFAULT;
673 		return 0;
674 
675 	case ATA_IOC_SET_IO32:
676 		val = (unsigned long) arg;
677 		rc = 0;
678 		spin_lock_irqsave(ap->lock, flags);
679 		if (ap->pflags & ATA_PFLAG_PIO32CHANGE) {
680 			if (val)
681 				ap->pflags |= ATA_PFLAG_PIO32;
682 			else
683 				ap->pflags &= ~ATA_PFLAG_PIO32;
684 		} else {
685 			if (val != ata_ioc32(ap))
686 				rc = -EINVAL;
687 		}
688 		spin_unlock_irqrestore(ap->lock, flags);
689 		return rc;
690 
691 	case HDIO_GET_IDENTITY:
692 		return ata_get_identity(ap, scsidev, arg);
693 
694 	case HDIO_DRIVE_CMD:
695 		if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
696 			return -EACCES;
697 		return ata_cmd_ioctl(scsidev, arg);
698 
699 	case HDIO_DRIVE_TASK:
700 		if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
701 			return -EACCES;
702 		return ata_task_ioctl(scsidev, arg);
703 
704 	default:
705 		rc = -ENOTTY;
706 		break;
707 	}
708 
709 	return rc;
710 }
711 EXPORT_SYMBOL_GPL(ata_sas_scsi_ioctl);
712 
713 int ata_scsi_ioctl(struct scsi_device *scsidev, int cmd, void __user *arg)
714 {
715 	return ata_sas_scsi_ioctl(ata_shost_to_port(scsidev->host),
716 				scsidev, cmd, arg);
717 }
718 EXPORT_SYMBOL_GPL(ata_scsi_ioctl);
719 
720 /**
721  *	ata_scsi_qc_new - acquire new ata_queued_cmd reference
722  *	@dev: ATA device to which the new command is attached
723  *	@cmd: SCSI command that originated this ATA command
724  *	@done: SCSI command completion function
725  *
726  *	Obtain a reference to an unused ata_queued_cmd structure,
727  *	which is the basic libata structure representing a single
728  *	ATA command sent to the hardware.
729  *
730  *	If a command was available, fill in the SCSI-specific
731  *	portions of the structure with information on the
732  *	current command.
733  *
734  *	LOCKING:
735  *	spin_lock_irqsave(host lock)
736  *
737  *	RETURNS:
738  *	Command allocated, or %NULL if none available.
739  */
740 static struct ata_queued_cmd *ata_scsi_qc_new(struct ata_device *dev,
741 					      struct scsi_cmnd *cmd,
742 					      void (*done)(struct scsi_cmnd *))
743 {
744 	struct ata_queued_cmd *qc;
745 
746 	qc = ata_qc_new_init(dev);
747 	if (qc) {
748 		qc->scsicmd = cmd;
749 		qc->scsidone = done;
750 
751 		qc->sg = scsi_sglist(cmd);
752 		qc->n_elem = scsi_sg_count(cmd);
753 	} else {
754 		cmd->result = (DID_OK << 16) | (QUEUE_FULL << 1);
755 		done(cmd);
756 	}
757 
758 	return qc;
759 }
760 
761 static void ata_qc_set_pc_nbytes(struct ata_queued_cmd *qc)
762 {
763 	struct scsi_cmnd *scmd = qc->scsicmd;
764 
765 	qc->extrabytes = scmd->request->extra_len;
766 	qc->nbytes = scsi_bufflen(scmd) + qc->extrabytes;
767 }
768 
769 /**
770  *	ata_dump_status - user friendly display of error info
771  *	@id: id of the port in question
772  *	@tf: ptr to filled out taskfile
773  *
774  *	Decode and dump the ATA error/status registers for the user so
775  *	that they have some idea what really happened at the non
776  *	make-believe layer.
777  *
778  *	LOCKING:
779  *	inherited from caller
780  */
781 static void ata_dump_status(unsigned id, struct ata_taskfile *tf)
782 {
783 	u8 stat = tf->command, err = tf->feature;
784 
785 	printk(KERN_WARNING "ata%u: status=0x%02x { ", id, stat);
786 	if (stat & ATA_BUSY) {
787 		printk("Busy }\n");	/* Data is not valid in this case */
788 	} else {
789 		if (stat & 0x40)	printk("DriveReady ");
790 		if (stat & 0x20)	printk("DeviceFault ");
791 		if (stat & 0x10)	printk("SeekComplete ");
792 		if (stat & 0x08)	printk("DataRequest ");
793 		if (stat & 0x04)	printk("CorrectedError ");
794 		if (stat & 0x02)	printk("Index ");
795 		if (stat & 0x01)	printk("Error ");
796 		printk("}\n");
797 
798 		if (err) {
799 			printk(KERN_WARNING "ata%u: error=0x%02x { ", id, err);
800 			if (err & 0x04)		printk("DriveStatusError ");
801 			if (err & 0x80) {
802 				if (err & 0x04)	printk("BadCRC ");
803 				else		printk("Sector ");
804 			}
805 			if (err & 0x40)		printk("UncorrectableError ");
806 			if (err & 0x10)		printk("SectorIdNotFound ");
807 			if (err & 0x02)		printk("TrackZeroNotFound ");
808 			if (err & 0x01)		printk("AddrMarkNotFound ");
809 			printk("}\n");
810 		}
811 	}
812 }
813 
814 /**
815  *	ata_to_sense_error - convert ATA error to SCSI error
816  *	@id: ATA device number
817  *	@drv_stat: value contained in ATA status register
818  *	@drv_err: value contained in ATA error register
819  *	@sk: the sense key we'll fill out
820  *	@asc: the additional sense code we'll fill out
821  *	@ascq: the additional sense code qualifier we'll fill out
822  *	@verbose: be verbose
823  *
824  *	Converts an ATA error into a SCSI error.  Fill out pointers to
825  *	SK, ASC, and ASCQ bytes for later use in fixed or descriptor
826  *	format sense blocks.
827  *
828  *	LOCKING:
829  *	spin_lock_irqsave(host lock)
830  */
831 static void ata_to_sense_error(unsigned id, u8 drv_stat, u8 drv_err, u8 *sk,
832 			       u8 *asc, u8 *ascq, int verbose)
833 {
834 	int i;
835 
836 	/* Based on the 3ware driver translation table */
837 	static const unsigned char sense_table[][4] = {
838 		/* BBD|ECC|ID|MAR */
839 		{0xd1, 		ABORTED_COMMAND, 0x00, 0x00}, 	// Device busy                  Aborted command
840 		/* BBD|ECC|ID */
841 		{0xd0,  	ABORTED_COMMAND, 0x00, 0x00}, 	// Device busy                  Aborted command
842 		/* ECC|MC|MARK */
843 		{0x61, 		HARDWARE_ERROR, 0x00, 0x00}, 	// Device fault                 Hardware error
844 		/* ICRC|ABRT */		/* NB: ICRC & !ABRT is BBD */
845 		{0x84, 		ABORTED_COMMAND, 0x47, 0x00}, 	// Data CRC error               SCSI parity error
846 		/* MC|ID|ABRT|TRK0|MARK */
847 		{0x37, 		NOT_READY, 0x04, 0x00}, 	// Unit offline                 Not ready
848 		/* MCR|MARK */
849 		{0x09, 		NOT_READY, 0x04, 0x00}, 	// Unrecovered disk error       Not ready
850 		/*  Bad address mark */
851 		{0x01, 		MEDIUM_ERROR, 0x13, 0x00}, 	// Address mark not found       Address mark not found for data field
852 		/* TRK0 */
853 		{0x02, 		HARDWARE_ERROR, 0x00, 0x00}, 	// Track 0 not found		  Hardware error
854 		/* Abort & !ICRC */
855 		{0x04, 		ABORTED_COMMAND, 0x00, 0x00}, 	// Aborted command              Aborted command
856 		/* Media change request */
857 		{0x08, 		NOT_READY, 0x04, 0x00}, 	// Media change request	  FIXME: faking offline
858 		/* SRV */
859 		{0x10, 		ABORTED_COMMAND, 0x14, 0x00}, 	// ID not found                 Recorded entity not found
860 		/* Media change */
861 		{0x08,  	NOT_READY, 0x04, 0x00}, 	// Media change		  FIXME: faking offline
862 		/* ECC */
863 		{0x40, 		MEDIUM_ERROR, 0x11, 0x04}, 	// Uncorrectable ECC error      Unrecovered read error
864 		/* BBD - block marked bad */
865 		{0x80, 		MEDIUM_ERROR, 0x11, 0x04}, 	// Block marked bad		  Medium error, unrecovered read error
866 		{0xFF, 0xFF, 0xFF, 0xFF}, // END mark
867 	};
868 	static const unsigned char stat_table[][4] = {
869 		/* Must be first because BUSY means no other bits valid */
870 		{0x80, 		ABORTED_COMMAND, 0x47, 0x00},	// Busy, fake parity for now
871 		{0x20, 		HARDWARE_ERROR,  0x00, 0x00}, 	// Device fault
872 		{0x08, 		ABORTED_COMMAND, 0x47, 0x00},	// Timed out in xfer, fake parity for now
873 		{0x04, 		RECOVERED_ERROR, 0x11, 0x00},	// Recovered ECC error	  Medium error, recovered
874 		{0xFF, 0xFF, 0xFF, 0xFF}, // END mark
875 	};
876 
877 	/*
878 	 *	Is this an error we can process/parse
879 	 */
880 	if (drv_stat & ATA_BUSY) {
881 		drv_err = 0;	/* Ignore the err bits, they're invalid */
882 	}
883 
884 	if (drv_err) {
885 		/* Look for drv_err */
886 		for (i = 0; sense_table[i][0] != 0xFF; i++) {
887 			/* Look for best matches first */
888 			if ((sense_table[i][0] & drv_err) ==
889 			    sense_table[i][0]) {
890 				*sk = sense_table[i][1];
891 				*asc = sense_table[i][2];
892 				*ascq = sense_table[i][3];
893 				goto translate_done;
894 			}
895 		}
896 		/* No immediate match */
897 		if (verbose)
898 			printk(KERN_WARNING "ata%u: no sense translation for "
899 			       "error 0x%02x\n", id, drv_err);
900 	}
901 
902 	/* Fall back to interpreting status bits */
903 	for (i = 0; stat_table[i][0] != 0xFF; i++) {
904 		if (stat_table[i][0] & drv_stat) {
905 			*sk = stat_table[i][1];
906 			*asc = stat_table[i][2];
907 			*ascq = stat_table[i][3];
908 			goto translate_done;
909 		}
910 	}
911 	/* No error?  Undecoded? */
912 	if (verbose)
913 		printk(KERN_WARNING "ata%u: no sense translation for "
914 		       "status: 0x%02x\n", id, drv_stat);
915 
916 	/* We need a sensible error return here, which is tricky, and one
917 	   that won't cause people to do things like return a disk wrongly */
918 	*sk = ABORTED_COMMAND;
919 	*asc = 0x00;
920 	*ascq = 0x00;
921 
922  translate_done:
923 	if (verbose)
924 		printk(KERN_ERR "ata%u: translated ATA stat/err 0x%02x/%02x "
925 		       "to SCSI SK/ASC/ASCQ 0x%x/%02x/%02x\n",
926 		       id, drv_stat, drv_err, *sk, *asc, *ascq);
927 	return;
928 }
929 
930 /*
931  *	ata_gen_passthru_sense - Generate check condition sense block.
932  *	@qc: Command that completed.
933  *
934  *	This function is specific to the ATA descriptor format sense
935  *	block specified for the ATA pass through commands.  Regardless
936  *	of whether the command errored or not, return a sense
937  *	block. Copy all controller registers into the sense
938  *	block. Clear sense key, ASC & ASCQ if there is no error.
939  *
940  *	LOCKING:
941  *	None.
942  */
943 static void ata_gen_passthru_sense(struct ata_queued_cmd *qc)
944 {
945 	struct scsi_cmnd *cmd = qc->scsicmd;
946 	struct ata_taskfile *tf = &qc->result_tf;
947 	unsigned char *sb = cmd->sense_buffer;
948 	unsigned char *desc = sb + 8;
949 	int verbose = qc->ap->ops->error_handler == NULL;
950 
951 	memset(sb, 0, SCSI_SENSE_BUFFERSIZE);
952 
953 	cmd->result = (DRIVER_SENSE << 24) | SAM_STAT_CHECK_CONDITION;
954 
955 	/*
956 	 * Use ata_to_sense_error() to map status register bits
957 	 * onto sense key, asc & ascq.
958 	 */
959 	if (qc->err_mask ||
960 	    tf->command & (ATA_BUSY | ATA_DF | ATA_ERR | ATA_DRQ)) {
961 		ata_to_sense_error(qc->ap->print_id, tf->command, tf->feature,
962 				   &sb[1], &sb[2], &sb[3], verbose);
963 		sb[1] &= 0x0f;
964 	}
965 
966 	/*
967 	 * Sense data is current and format is descriptor.
968 	 */
969 	sb[0] = 0x72;
970 
971 	desc[0] = 0x09;
972 
973 	/* set length of additional sense data */
974 	sb[7] = 14;
975 	desc[1] = 12;
976 
977 	/*
978 	 * Copy registers into sense buffer.
979 	 */
980 	desc[2] = 0x00;
981 	desc[3] = tf->feature;	/* == error reg */
982 	desc[5] = tf->nsect;
983 	desc[7] = tf->lbal;
984 	desc[9] = tf->lbam;
985 	desc[11] = tf->lbah;
986 	desc[12] = tf->device;
987 	desc[13] = tf->command; /* == status reg */
988 
989 	/*
990 	 * Fill in Extend bit, and the high order bytes
991 	 * if applicable.
992 	 */
993 	if (tf->flags & ATA_TFLAG_LBA48) {
994 		desc[2] |= 0x01;
995 		desc[4] = tf->hob_nsect;
996 		desc[6] = tf->hob_lbal;
997 		desc[8] = tf->hob_lbam;
998 		desc[10] = tf->hob_lbah;
999 	}
1000 }
1001 
1002 /**
1003  *	ata_gen_ata_sense - generate a SCSI fixed sense block
1004  *	@qc: Command that we are erroring out
1005  *
1006  *	Generate sense block for a failed ATA command @qc.  Descriptor
1007  *	format is used to accomodate LBA48 block address.
1008  *
1009  *	LOCKING:
1010  *	None.
1011  */
1012 static void ata_gen_ata_sense(struct ata_queued_cmd *qc)
1013 {
1014 	struct ata_device *dev = qc->dev;
1015 	struct scsi_cmnd *cmd = qc->scsicmd;
1016 	struct ata_taskfile *tf = &qc->result_tf;
1017 	unsigned char *sb = cmd->sense_buffer;
1018 	unsigned char *desc = sb + 8;
1019 	int verbose = qc->ap->ops->error_handler == NULL;
1020 	u64 block;
1021 
1022 	memset(sb, 0, SCSI_SENSE_BUFFERSIZE);
1023 
1024 	cmd->result = (DRIVER_SENSE << 24) | SAM_STAT_CHECK_CONDITION;
1025 
1026 	/* sense data is current and format is descriptor */
1027 	sb[0] = 0x72;
1028 
1029 	/* Use ata_to_sense_error() to map status register bits
1030 	 * onto sense key, asc & ascq.
1031 	 */
1032 	if (qc->err_mask ||
1033 	    tf->command & (ATA_BUSY | ATA_DF | ATA_ERR | ATA_DRQ)) {
1034 		ata_to_sense_error(qc->ap->print_id, tf->command, tf->feature,
1035 				   &sb[1], &sb[2], &sb[3], verbose);
1036 		sb[1] &= 0x0f;
1037 	}
1038 
1039 	block = ata_tf_read_block(&qc->result_tf, dev);
1040 
1041 	/* information sense data descriptor */
1042 	sb[7] = 12;
1043 	desc[0] = 0x00;
1044 	desc[1] = 10;
1045 
1046 	desc[2] |= 0x80;	/* valid */
1047 	desc[6] = block >> 40;
1048 	desc[7] = block >> 32;
1049 	desc[8] = block >> 24;
1050 	desc[9] = block >> 16;
1051 	desc[10] = block >> 8;
1052 	desc[11] = block;
1053 }
1054 
1055 static void ata_scsi_sdev_config(struct scsi_device *sdev)
1056 {
1057 	sdev->use_10_for_rw = 1;
1058 	sdev->use_10_for_ms = 1;
1059 
1060 	/* Schedule policy is determined by ->qc_defer() callback and
1061 	 * it needs to see every deferred qc.  Set dev_blocked to 1 to
1062 	 * prevent SCSI midlayer from automatically deferring
1063 	 * requests.
1064 	 */
1065 	sdev->max_device_blocked = 1;
1066 }
1067 
1068 /**
1069  *	atapi_drain_needed - Check whether data transfer may overflow
1070  *	@rq: request to be checked
1071  *
1072  *	ATAPI commands which transfer variable length data to host
1073  *	might overflow due to application error or hardare bug.  This
1074  *	function checks whether overflow should be drained and ignored
1075  *	for @request.
1076  *
1077  *	LOCKING:
1078  *	None.
1079  *
1080  *	RETURNS:
1081  *	1 if ; otherwise, 0.
1082  */
1083 static int atapi_drain_needed(struct request *rq)
1084 {
1085 	if (likely(!blk_pc_request(rq)))
1086 		return 0;
1087 
1088 	if (!blk_rq_bytes(rq) || (rq->cmd_flags & REQ_RW))
1089 		return 0;
1090 
1091 	return atapi_cmd_type(rq->cmd[0]) == ATAPI_MISC;
1092 }
1093 
1094 static int ata_scsi_dev_config(struct scsi_device *sdev,
1095 			       struct ata_device *dev)
1096 {
1097 	if (!ata_id_has_unload(dev->id))
1098 		dev->flags |= ATA_DFLAG_NO_UNLOAD;
1099 
1100 	/* configure max sectors */
1101 	blk_queue_max_hw_sectors(sdev->request_queue, dev->max_sectors);
1102 
1103 	if (dev->class == ATA_DEV_ATAPI) {
1104 		struct request_queue *q = sdev->request_queue;
1105 		void *buf;
1106 
1107 		/* set the min alignment and padding */
1108 		blk_queue_update_dma_alignment(sdev->request_queue,
1109 					       ATA_DMA_PAD_SZ - 1);
1110 		blk_queue_update_dma_pad(sdev->request_queue,
1111 					 ATA_DMA_PAD_SZ - 1);
1112 
1113 		/* configure draining */
1114 		buf = kmalloc(ATAPI_MAX_DRAIN, q->bounce_gfp | GFP_KERNEL);
1115 		if (!buf) {
1116 			ata_dev_printk(dev, KERN_ERR,
1117 				       "drain buffer allocation failed\n");
1118 			return -ENOMEM;
1119 		}
1120 
1121 		blk_queue_dma_drain(q, atapi_drain_needed, buf, ATAPI_MAX_DRAIN);
1122 	} else {
1123 		/* ATA devices must be sector aligned */
1124 		blk_queue_update_dma_alignment(sdev->request_queue,
1125 					       ATA_SECT_SIZE - 1);
1126 		sdev->manage_start_stop = 1;
1127 	}
1128 
1129 	if (dev->flags & ATA_DFLAG_AN)
1130 		set_bit(SDEV_EVT_MEDIA_CHANGE, sdev->supported_events);
1131 
1132 	if (dev->flags & ATA_DFLAG_NCQ) {
1133 		int depth;
1134 
1135 		depth = min(sdev->host->can_queue, ata_id_queue_depth(dev->id));
1136 		depth = min(ATA_MAX_QUEUE - 1, depth);
1137 		scsi_adjust_queue_depth(sdev, MSG_SIMPLE_TAG, depth);
1138 	}
1139 
1140 	return 0;
1141 }
1142 
1143 /**
1144  *	ata_scsi_slave_config - Set SCSI device attributes
1145  *	@sdev: SCSI device to examine
1146  *
1147  *	This is called before we actually start reading
1148  *	and writing to the device, to configure certain
1149  *	SCSI mid-layer behaviors.
1150  *
1151  *	LOCKING:
1152  *	Defined by SCSI layer.  We don't really care.
1153  */
1154 
1155 int ata_scsi_slave_config(struct scsi_device *sdev)
1156 {
1157 	struct ata_port *ap = ata_shost_to_port(sdev->host);
1158 	struct ata_device *dev = __ata_scsi_find_dev(ap, sdev);
1159 	int rc = 0;
1160 
1161 	ata_scsi_sdev_config(sdev);
1162 
1163 	if (dev)
1164 		rc = ata_scsi_dev_config(sdev, dev);
1165 
1166 	return rc;
1167 }
1168 
1169 /**
1170  *	ata_scsi_slave_destroy - SCSI device is about to be destroyed
1171  *	@sdev: SCSI device to be destroyed
1172  *
1173  *	@sdev is about to be destroyed for hot/warm unplugging.  If
1174  *	this unplugging was initiated by libata as indicated by NULL
1175  *	dev->sdev, this function doesn't have to do anything.
1176  *	Otherwise, SCSI layer initiated warm-unplug is in progress.
1177  *	Clear dev->sdev, schedule the device for ATA detach and invoke
1178  *	EH.
1179  *
1180  *	LOCKING:
1181  *	Defined by SCSI layer.  We don't really care.
1182  */
1183 void ata_scsi_slave_destroy(struct scsi_device *sdev)
1184 {
1185 	struct ata_port *ap = ata_shost_to_port(sdev->host);
1186 	struct request_queue *q = sdev->request_queue;
1187 	unsigned long flags;
1188 	struct ata_device *dev;
1189 
1190 	if (!ap->ops->error_handler)
1191 		return;
1192 
1193 	spin_lock_irqsave(ap->lock, flags);
1194 	dev = __ata_scsi_find_dev(ap, sdev);
1195 	if (dev && dev->sdev) {
1196 		/* SCSI device already in CANCEL state, no need to offline it */
1197 		dev->sdev = NULL;
1198 		dev->flags |= ATA_DFLAG_DETACH;
1199 		ata_port_schedule_eh(ap);
1200 	}
1201 	spin_unlock_irqrestore(ap->lock, flags);
1202 
1203 	kfree(q->dma_drain_buffer);
1204 	q->dma_drain_buffer = NULL;
1205 	q->dma_drain_size = 0;
1206 }
1207 
1208 /**
1209  *	ata_scsi_change_queue_depth - SCSI callback for queue depth config
1210  *	@sdev: SCSI device to configure queue depth for
1211  *	@queue_depth: new queue depth
1212  *	@reason: calling context
1213  *
1214  *	This is libata standard hostt->change_queue_depth callback.
1215  *	SCSI will call into this callback when user tries to set queue
1216  *	depth via sysfs.
1217  *
1218  *	LOCKING:
1219  *	SCSI layer (we don't care)
1220  *
1221  *	RETURNS:
1222  *	Newly configured queue depth.
1223  */
1224 int ata_scsi_change_queue_depth(struct scsi_device *sdev, int queue_depth,
1225 				int reason)
1226 {
1227 	struct ata_port *ap = ata_shost_to_port(sdev->host);
1228 	struct ata_device *dev;
1229 	unsigned long flags;
1230 
1231 	if (reason != SCSI_QDEPTH_DEFAULT)
1232 		return -EOPNOTSUPP;
1233 
1234 	if (queue_depth < 1 || queue_depth == sdev->queue_depth)
1235 		return sdev->queue_depth;
1236 
1237 	dev = ata_scsi_find_dev(ap, sdev);
1238 	if (!dev || !ata_dev_enabled(dev))
1239 		return sdev->queue_depth;
1240 
1241 	/* NCQ enabled? */
1242 	spin_lock_irqsave(ap->lock, flags);
1243 	dev->flags &= ~ATA_DFLAG_NCQ_OFF;
1244 	if (queue_depth == 1 || !ata_ncq_enabled(dev)) {
1245 		dev->flags |= ATA_DFLAG_NCQ_OFF;
1246 		queue_depth = 1;
1247 	}
1248 	spin_unlock_irqrestore(ap->lock, flags);
1249 
1250 	/* limit and apply queue depth */
1251 	queue_depth = min(queue_depth, sdev->host->can_queue);
1252 	queue_depth = min(queue_depth, ata_id_queue_depth(dev->id));
1253 	queue_depth = min(queue_depth, ATA_MAX_QUEUE - 1);
1254 
1255 	if (sdev->queue_depth == queue_depth)
1256 		return -EINVAL;
1257 
1258 	scsi_adjust_queue_depth(sdev, MSG_SIMPLE_TAG, queue_depth);
1259 	return queue_depth;
1260 }
1261 
1262 /**
1263  *	ata_scsi_start_stop_xlat - Translate SCSI START STOP UNIT command
1264  *	@qc: Storage for translated ATA taskfile
1265  *
1266  *	Sets up an ATA taskfile to issue STANDBY (to stop) or READ VERIFY
1267  *	(to start). Perhaps these commands should be preceded by
1268  *	CHECK POWER MODE to see what power mode the device is already in.
1269  *	[See SAT revision 5 at www.t10.org]
1270  *
1271  *	LOCKING:
1272  *	spin_lock_irqsave(host lock)
1273  *
1274  *	RETURNS:
1275  *	Zero on success, non-zero on error.
1276  */
1277 static unsigned int ata_scsi_start_stop_xlat(struct ata_queued_cmd *qc)
1278 {
1279 	struct scsi_cmnd *scmd = qc->scsicmd;
1280 	struct ata_taskfile *tf = &qc->tf;
1281 	const u8 *cdb = scmd->cmnd;
1282 
1283 	if (scmd->cmd_len < 5)
1284 		goto invalid_fld;
1285 
1286 	tf->flags |= ATA_TFLAG_DEVICE | ATA_TFLAG_ISADDR;
1287 	tf->protocol = ATA_PROT_NODATA;
1288 	if (cdb[1] & 0x1) {
1289 		;	/* ignore IMMED bit, violates sat-r05 */
1290 	}
1291 	if (cdb[4] & 0x2)
1292 		goto invalid_fld;       /* LOEJ bit set not supported */
1293 	if (((cdb[4] >> 4) & 0xf) != 0)
1294 		goto invalid_fld;       /* power conditions not supported */
1295 
1296 	if (cdb[4] & 0x1) {
1297 		tf->nsect = 1;	/* 1 sector, lba=0 */
1298 
1299 		if (qc->dev->flags & ATA_DFLAG_LBA) {
1300 			tf->flags |= ATA_TFLAG_LBA;
1301 
1302 			tf->lbah = 0x0;
1303 			tf->lbam = 0x0;
1304 			tf->lbal = 0x0;
1305 			tf->device |= ATA_LBA;
1306 		} else {
1307 			/* CHS */
1308 			tf->lbal = 0x1; /* sect */
1309 			tf->lbam = 0x0; /* cyl low */
1310 			tf->lbah = 0x0; /* cyl high */
1311 		}
1312 
1313 		tf->command = ATA_CMD_VERIFY;	/* READ VERIFY */
1314 	} else {
1315 		/* Some odd clown BIOSen issue spindown on power off (ACPI S4
1316 		 * or S5) causing some drives to spin up and down again.
1317 		 */
1318 		if ((qc->ap->flags & ATA_FLAG_NO_POWEROFF_SPINDOWN) &&
1319 		    system_state == SYSTEM_POWER_OFF)
1320 			goto skip;
1321 
1322 		if ((qc->ap->flags & ATA_FLAG_NO_HIBERNATE_SPINDOWN) &&
1323 		     system_entering_hibernation())
1324 			goto skip;
1325 
1326 		/* Issue ATA STANDBY IMMEDIATE command */
1327 		tf->command = ATA_CMD_STANDBYNOW1;
1328 	}
1329 
1330 	/*
1331 	 * Standby and Idle condition timers could be implemented but that
1332 	 * would require libata to implement the Power condition mode page
1333 	 * and allow the user to change it. Changing mode pages requires
1334 	 * MODE SELECT to be implemented.
1335 	 */
1336 
1337 	return 0;
1338 
1339  invalid_fld:
1340 	ata_scsi_set_sense(scmd, ILLEGAL_REQUEST, 0x24, 0x0);
1341 	/* "Invalid field in cbd" */
1342 	return 1;
1343  skip:
1344 	scmd->result = SAM_STAT_GOOD;
1345 	return 1;
1346 }
1347 
1348 
1349 /**
1350  *	ata_scsi_flush_xlat - Translate SCSI SYNCHRONIZE CACHE command
1351  *	@qc: Storage for translated ATA taskfile
1352  *
1353  *	Sets up an ATA taskfile to issue FLUSH CACHE or
1354  *	FLUSH CACHE EXT.
1355  *
1356  *	LOCKING:
1357  *	spin_lock_irqsave(host lock)
1358  *
1359  *	RETURNS:
1360  *	Zero on success, non-zero on error.
1361  */
1362 static unsigned int ata_scsi_flush_xlat(struct ata_queued_cmd *qc)
1363 {
1364 	struct ata_taskfile *tf = &qc->tf;
1365 
1366 	tf->flags |= ATA_TFLAG_DEVICE;
1367 	tf->protocol = ATA_PROT_NODATA;
1368 
1369 	if (qc->dev->flags & ATA_DFLAG_FLUSH_EXT)
1370 		tf->command = ATA_CMD_FLUSH_EXT;
1371 	else
1372 		tf->command = ATA_CMD_FLUSH;
1373 
1374 	/* flush is critical for IO integrity, consider it an IO command */
1375 	qc->flags |= ATA_QCFLAG_IO;
1376 
1377 	return 0;
1378 }
1379 
1380 /**
1381  *	scsi_6_lba_len - Get LBA and transfer length
1382  *	@cdb: SCSI command to translate
1383  *
1384  *	Calculate LBA and transfer length for 6-byte commands.
1385  *
1386  *	RETURNS:
1387  *	@plba: the LBA
1388  *	@plen: the transfer length
1389  */
1390 static void scsi_6_lba_len(const u8 *cdb, u64 *plba, u32 *plen)
1391 {
1392 	u64 lba = 0;
1393 	u32 len;
1394 
1395 	VPRINTK("six-byte command\n");
1396 
1397 	lba |= ((u64)(cdb[1] & 0x1f)) << 16;
1398 	lba |= ((u64)cdb[2]) << 8;
1399 	lba |= ((u64)cdb[3]);
1400 
1401 	len = cdb[4];
1402 
1403 	*plba = lba;
1404 	*plen = len;
1405 }
1406 
1407 /**
1408  *	scsi_10_lba_len - Get LBA and transfer length
1409  *	@cdb: SCSI command to translate
1410  *
1411  *	Calculate LBA and transfer length for 10-byte commands.
1412  *
1413  *	RETURNS:
1414  *	@plba: the LBA
1415  *	@plen: the transfer length
1416  */
1417 static void scsi_10_lba_len(const u8 *cdb, u64 *plba, u32 *plen)
1418 {
1419 	u64 lba = 0;
1420 	u32 len = 0;
1421 
1422 	VPRINTK("ten-byte command\n");
1423 
1424 	lba |= ((u64)cdb[2]) << 24;
1425 	lba |= ((u64)cdb[3]) << 16;
1426 	lba |= ((u64)cdb[4]) << 8;
1427 	lba |= ((u64)cdb[5]);
1428 
1429 	len |= ((u32)cdb[7]) << 8;
1430 	len |= ((u32)cdb[8]);
1431 
1432 	*plba = lba;
1433 	*plen = len;
1434 }
1435 
1436 /**
1437  *	scsi_16_lba_len - Get LBA and transfer length
1438  *	@cdb: SCSI command to translate
1439  *
1440  *	Calculate LBA and transfer length for 16-byte commands.
1441  *
1442  *	RETURNS:
1443  *	@plba: the LBA
1444  *	@plen: the transfer length
1445  */
1446 static void scsi_16_lba_len(const u8 *cdb, u64 *plba, u32 *plen)
1447 {
1448 	u64 lba = 0;
1449 	u32 len = 0;
1450 
1451 	VPRINTK("sixteen-byte command\n");
1452 
1453 	lba |= ((u64)cdb[2]) << 56;
1454 	lba |= ((u64)cdb[3]) << 48;
1455 	lba |= ((u64)cdb[4]) << 40;
1456 	lba |= ((u64)cdb[5]) << 32;
1457 	lba |= ((u64)cdb[6]) << 24;
1458 	lba |= ((u64)cdb[7]) << 16;
1459 	lba |= ((u64)cdb[8]) << 8;
1460 	lba |= ((u64)cdb[9]);
1461 
1462 	len |= ((u32)cdb[10]) << 24;
1463 	len |= ((u32)cdb[11]) << 16;
1464 	len |= ((u32)cdb[12]) << 8;
1465 	len |= ((u32)cdb[13]);
1466 
1467 	*plba = lba;
1468 	*plen = len;
1469 }
1470 
1471 /**
1472  *	ata_scsi_verify_xlat - Translate SCSI VERIFY command into an ATA one
1473  *	@qc: Storage for translated ATA taskfile
1474  *
1475  *	Converts SCSI VERIFY command to an ATA READ VERIFY command.
1476  *
1477  *	LOCKING:
1478  *	spin_lock_irqsave(host lock)
1479  *
1480  *	RETURNS:
1481  *	Zero on success, non-zero on error.
1482  */
1483 static unsigned int ata_scsi_verify_xlat(struct ata_queued_cmd *qc)
1484 {
1485 	struct scsi_cmnd *scmd = qc->scsicmd;
1486 	struct ata_taskfile *tf = &qc->tf;
1487 	struct ata_device *dev = qc->dev;
1488 	u64 dev_sectors = qc->dev->n_sectors;
1489 	const u8 *cdb = scmd->cmnd;
1490 	u64 block;
1491 	u32 n_block;
1492 
1493 	tf->flags |= ATA_TFLAG_ISADDR | ATA_TFLAG_DEVICE;
1494 	tf->protocol = ATA_PROT_NODATA;
1495 
1496 	if (cdb[0] == VERIFY) {
1497 		if (scmd->cmd_len < 10)
1498 			goto invalid_fld;
1499 		scsi_10_lba_len(cdb, &block, &n_block);
1500 	} else if (cdb[0] == VERIFY_16) {
1501 		if (scmd->cmd_len < 16)
1502 			goto invalid_fld;
1503 		scsi_16_lba_len(cdb, &block, &n_block);
1504 	} else
1505 		goto invalid_fld;
1506 
1507 	if (!n_block)
1508 		goto nothing_to_do;
1509 	if (block >= dev_sectors)
1510 		goto out_of_range;
1511 	if ((block + n_block) > dev_sectors)
1512 		goto out_of_range;
1513 
1514 	if (dev->flags & ATA_DFLAG_LBA) {
1515 		tf->flags |= ATA_TFLAG_LBA;
1516 
1517 		if (lba_28_ok(block, n_block)) {
1518 			/* use LBA28 */
1519 			tf->command = ATA_CMD_VERIFY;
1520 			tf->device |= (block >> 24) & 0xf;
1521 		} else if (lba_48_ok(block, n_block)) {
1522 			if (!(dev->flags & ATA_DFLAG_LBA48))
1523 				goto out_of_range;
1524 
1525 			/* use LBA48 */
1526 			tf->flags |= ATA_TFLAG_LBA48;
1527 			tf->command = ATA_CMD_VERIFY_EXT;
1528 
1529 			tf->hob_nsect = (n_block >> 8) & 0xff;
1530 
1531 			tf->hob_lbah = (block >> 40) & 0xff;
1532 			tf->hob_lbam = (block >> 32) & 0xff;
1533 			tf->hob_lbal = (block >> 24) & 0xff;
1534 		} else
1535 			/* request too large even for LBA48 */
1536 			goto out_of_range;
1537 
1538 		tf->nsect = n_block & 0xff;
1539 
1540 		tf->lbah = (block >> 16) & 0xff;
1541 		tf->lbam = (block >> 8) & 0xff;
1542 		tf->lbal = block & 0xff;
1543 
1544 		tf->device |= ATA_LBA;
1545 	} else {
1546 		/* CHS */
1547 		u32 sect, head, cyl, track;
1548 
1549 		if (!lba_28_ok(block, n_block))
1550 			goto out_of_range;
1551 
1552 		/* Convert LBA to CHS */
1553 		track = (u32)block / dev->sectors;
1554 		cyl   = track / dev->heads;
1555 		head  = track % dev->heads;
1556 		sect  = (u32)block % dev->sectors + 1;
1557 
1558 		DPRINTK("block %u track %u cyl %u head %u sect %u\n",
1559 			(u32)block, track, cyl, head, sect);
1560 
1561 		/* Check whether the converted CHS can fit.
1562 		   Cylinder: 0-65535
1563 		   Head: 0-15
1564 		   Sector: 1-255*/
1565 		if ((cyl >> 16) || (head >> 4) || (sect >> 8) || (!sect))
1566 			goto out_of_range;
1567 
1568 		tf->command = ATA_CMD_VERIFY;
1569 		tf->nsect = n_block & 0xff; /* Sector count 0 means 256 sectors */
1570 		tf->lbal = sect;
1571 		tf->lbam = cyl;
1572 		tf->lbah = cyl >> 8;
1573 		tf->device |= head;
1574 	}
1575 
1576 	return 0;
1577 
1578 invalid_fld:
1579 	ata_scsi_set_sense(scmd, ILLEGAL_REQUEST, 0x24, 0x0);
1580 	/* "Invalid field in cbd" */
1581 	return 1;
1582 
1583 out_of_range:
1584 	ata_scsi_set_sense(scmd, ILLEGAL_REQUEST, 0x21, 0x0);
1585 	/* "Logical Block Address out of range" */
1586 	return 1;
1587 
1588 nothing_to_do:
1589 	scmd->result = SAM_STAT_GOOD;
1590 	return 1;
1591 }
1592 
1593 /**
1594  *	ata_scsi_rw_xlat - Translate SCSI r/w command into an ATA one
1595  *	@qc: Storage for translated ATA taskfile
1596  *
1597  *	Converts any of six SCSI read/write commands into the
1598  *	ATA counterpart, including starting sector (LBA),
1599  *	sector count, and taking into account the device's LBA48
1600  *	support.
1601  *
1602  *	Commands %READ_6, %READ_10, %READ_16, %WRITE_6, %WRITE_10, and
1603  *	%WRITE_16 are currently supported.
1604  *
1605  *	LOCKING:
1606  *	spin_lock_irqsave(host lock)
1607  *
1608  *	RETURNS:
1609  *	Zero on success, non-zero on error.
1610  */
1611 static unsigned int ata_scsi_rw_xlat(struct ata_queued_cmd *qc)
1612 {
1613 	struct scsi_cmnd *scmd = qc->scsicmd;
1614 	const u8 *cdb = scmd->cmnd;
1615 	unsigned int tf_flags = 0;
1616 	u64 block;
1617 	u32 n_block;
1618 	int rc;
1619 
1620 	if (cdb[0] == WRITE_10 || cdb[0] == WRITE_6 || cdb[0] == WRITE_16)
1621 		tf_flags |= ATA_TFLAG_WRITE;
1622 
1623 	/* Calculate the SCSI LBA, transfer length and FUA. */
1624 	switch (cdb[0]) {
1625 	case READ_10:
1626 	case WRITE_10:
1627 		if (unlikely(scmd->cmd_len < 10))
1628 			goto invalid_fld;
1629 		scsi_10_lba_len(cdb, &block, &n_block);
1630 		if (unlikely(cdb[1] & (1 << 3)))
1631 			tf_flags |= ATA_TFLAG_FUA;
1632 		break;
1633 	case READ_6:
1634 	case WRITE_6:
1635 		if (unlikely(scmd->cmd_len < 6))
1636 			goto invalid_fld;
1637 		scsi_6_lba_len(cdb, &block, &n_block);
1638 
1639 		/* for 6-byte r/w commands, transfer length 0
1640 		 * means 256 blocks of data, not 0 block.
1641 		 */
1642 		if (!n_block)
1643 			n_block = 256;
1644 		break;
1645 	case READ_16:
1646 	case WRITE_16:
1647 		if (unlikely(scmd->cmd_len < 16))
1648 			goto invalid_fld;
1649 		scsi_16_lba_len(cdb, &block, &n_block);
1650 		if (unlikely(cdb[1] & (1 << 3)))
1651 			tf_flags |= ATA_TFLAG_FUA;
1652 		break;
1653 	default:
1654 		DPRINTK("no-byte command\n");
1655 		goto invalid_fld;
1656 	}
1657 
1658 	/* Check and compose ATA command */
1659 	if (!n_block)
1660 		/* For 10-byte and 16-byte SCSI R/W commands, transfer
1661 		 * length 0 means transfer 0 block of data.
1662 		 * However, for ATA R/W commands, sector count 0 means
1663 		 * 256 or 65536 sectors, not 0 sectors as in SCSI.
1664 		 *
1665 		 * WARNING: one or two older ATA drives treat 0 as 0...
1666 		 */
1667 		goto nothing_to_do;
1668 
1669 	qc->flags |= ATA_QCFLAG_IO;
1670 	qc->nbytes = n_block * ATA_SECT_SIZE;
1671 
1672 	rc = ata_build_rw_tf(&qc->tf, qc->dev, block, n_block, tf_flags,
1673 			     qc->tag);
1674 	if (likely(rc == 0))
1675 		return 0;
1676 
1677 	if (rc == -ERANGE)
1678 		goto out_of_range;
1679 	/* treat all other errors as -EINVAL, fall through */
1680 invalid_fld:
1681 	ata_scsi_set_sense(scmd, ILLEGAL_REQUEST, 0x24, 0x0);
1682 	/* "Invalid field in cbd" */
1683 	return 1;
1684 
1685 out_of_range:
1686 	ata_scsi_set_sense(scmd, ILLEGAL_REQUEST, 0x21, 0x0);
1687 	/* "Logical Block Address out of range" */
1688 	return 1;
1689 
1690 nothing_to_do:
1691 	scmd->result = SAM_STAT_GOOD;
1692 	return 1;
1693 }
1694 
1695 static void ata_scsi_qc_complete(struct ata_queued_cmd *qc)
1696 {
1697 	struct ata_port *ap = qc->ap;
1698 	struct scsi_cmnd *cmd = qc->scsicmd;
1699 	u8 *cdb = cmd->cmnd;
1700 	int need_sense = (qc->err_mask != 0);
1701 
1702 	/* For ATA pass thru (SAT) commands, generate a sense block if
1703 	 * user mandated it or if there's an error.  Note that if we
1704 	 * generate because the user forced us to, a check condition
1705 	 * is generated and the ATA register values are returned
1706 	 * whether the command completed successfully or not. If there
1707 	 * was no error, SK, ASC and ASCQ will all be zero.
1708 	 */
1709 	if (((cdb[0] == ATA_16) || (cdb[0] == ATA_12)) &&
1710 	    ((cdb[2] & 0x20) || need_sense)) {
1711 		ata_gen_passthru_sense(qc);
1712 	} else {
1713 		if (!need_sense) {
1714 			cmd->result = SAM_STAT_GOOD;
1715 		} else {
1716 			/* TODO: decide which descriptor format to use
1717 			 * for 48b LBA devices and call that here
1718 			 * instead of the fixed desc, which is only
1719 			 * good for smaller LBA (and maybe CHS?)
1720 			 * devices.
1721 			 */
1722 			ata_gen_ata_sense(qc);
1723 		}
1724 	}
1725 
1726 	if (need_sense && !ap->ops->error_handler)
1727 		ata_dump_status(ap->print_id, &qc->result_tf);
1728 
1729 	qc->scsidone(cmd);
1730 
1731 	ata_qc_free(qc);
1732 }
1733 
1734 /**
1735  *	ata_scsi_translate - Translate then issue SCSI command to ATA device
1736  *	@dev: ATA device to which the command is addressed
1737  *	@cmd: SCSI command to execute
1738  *	@done: SCSI command completion function
1739  *	@xlat_func: Actor which translates @cmd to an ATA taskfile
1740  *
1741  *	Our ->queuecommand() function has decided that the SCSI
1742  *	command issued can be directly translated into an ATA
1743  *	command, rather than handled internally.
1744  *
1745  *	This function sets up an ata_queued_cmd structure for the
1746  *	SCSI command, and sends that ata_queued_cmd to the hardware.
1747  *
1748  *	The xlat_func argument (actor) returns 0 if ready to execute
1749  *	ATA command, else 1 to finish translation. If 1 is returned
1750  *	then cmd->result (and possibly cmd->sense_buffer) are assumed
1751  *	to be set reflecting an error condition or clean (early)
1752  *	termination.
1753  *
1754  *	LOCKING:
1755  *	spin_lock_irqsave(host lock)
1756  *
1757  *	RETURNS:
1758  *	0 on success, SCSI_ML_QUEUE_DEVICE_BUSY if the command
1759  *	needs to be deferred.
1760  */
1761 static int ata_scsi_translate(struct ata_device *dev, struct scsi_cmnd *cmd,
1762 			      void (*done)(struct scsi_cmnd *),
1763 			      ata_xlat_func_t xlat_func)
1764 {
1765 	struct ata_port *ap = dev->link->ap;
1766 	struct ata_queued_cmd *qc;
1767 	int rc;
1768 
1769 	VPRINTK("ENTER\n");
1770 
1771 	qc = ata_scsi_qc_new(dev, cmd, done);
1772 	if (!qc)
1773 		goto err_mem;
1774 
1775 	/* data is present; dma-map it */
1776 	if (cmd->sc_data_direction == DMA_FROM_DEVICE ||
1777 	    cmd->sc_data_direction == DMA_TO_DEVICE) {
1778 		if (unlikely(scsi_bufflen(cmd) < 1)) {
1779 			ata_dev_printk(dev, KERN_WARNING,
1780 				       "WARNING: zero len r/w req\n");
1781 			goto err_did;
1782 		}
1783 
1784 		ata_sg_init(qc, scsi_sglist(cmd), scsi_sg_count(cmd));
1785 
1786 		qc->dma_dir = cmd->sc_data_direction;
1787 	}
1788 
1789 	qc->complete_fn = ata_scsi_qc_complete;
1790 
1791 	if (xlat_func(qc))
1792 		goto early_finish;
1793 
1794 	if (ap->ops->qc_defer) {
1795 		if ((rc = ap->ops->qc_defer(qc)))
1796 			goto defer;
1797 	}
1798 
1799 	/* select device, send command to hardware */
1800 	ata_qc_issue(qc);
1801 
1802 	VPRINTK("EXIT\n");
1803 	return 0;
1804 
1805 early_finish:
1806 	ata_qc_free(qc);
1807 	qc->scsidone(cmd);
1808 	DPRINTK("EXIT - early finish (good or error)\n");
1809 	return 0;
1810 
1811 err_did:
1812 	ata_qc_free(qc);
1813 	cmd->result = (DID_ERROR << 16);
1814 	qc->scsidone(cmd);
1815 err_mem:
1816 	DPRINTK("EXIT - internal\n");
1817 	return 0;
1818 
1819 defer:
1820 	ata_qc_free(qc);
1821 	DPRINTK("EXIT - defer\n");
1822 	if (rc == ATA_DEFER_LINK)
1823 		return SCSI_MLQUEUE_DEVICE_BUSY;
1824 	else
1825 		return SCSI_MLQUEUE_HOST_BUSY;
1826 }
1827 
1828 /**
1829  *	ata_scsi_rbuf_get - Map response buffer.
1830  *	@cmd: SCSI command containing buffer to be mapped.
1831  *	@flags: unsigned long variable to store irq enable status
1832  *	@copy_in: copy in from user buffer
1833  *
1834  *	Prepare buffer for simulated SCSI commands.
1835  *
1836  *	LOCKING:
1837  *	spin_lock_irqsave(ata_scsi_rbuf_lock) on success
1838  *
1839  *	RETURNS:
1840  *	Pointer to response buffer.
1841  */
1842 static void *ata_scsi_rbuf_get(struct scsi_cmnd *cmd, bool copy_in,
1843 			       unsigned long *flags)
1844 {
1845 	spin_lock_irqsave(&ata_scsi_rbuf_lock, *flags);
1846 
1847 	memset(ata_scsi_rbuf, 0, ATA_SCSI_RBUF_SIZE);
1848 	if (copy_in)
1849 		sg_copy_to_buffer(scsi_sglist(cmd), scsi_sg_count(cmd),
1850 				  ata_scsi_rbuf, ATA_SCSI_RBUF_SIZE);
1851 	return ata_scsi_rbuf;
1852 }
1853 
1854 /**
1855  *	ata_scsi_rbuf_put - Unmap response buffer.
1856  *	@cmd: SCSI command containing buffer to be unmapped.
1857  *	@copy_out: copy out result
1858  *	@flags: @flags passed to ata_scsi_rbuf_get()
1859  *
1860  *	Returns rbuf buffer.  The result is copied to @cmd's buffer if
1861  *	@copy_back is true.
1862  *
1863  *	LOCKING:
1864  *	Unlocks ata_scsi_rbuf_lock.
1865  */
1866 static inline void ata_scsi_rbuf_put(struct scsi_cmnd *cmd, bool copy_out,
1867 				     unsigned long *flags)
1868 {
1869 	if (copy_out)
1870 		sg_copy_from_buffer(scsi_sglist(cmd), scsi_sg_count(cmd),
1871 				    ata_scsi_rbuf, ATA_SCSI_RBUF_SIZE);
1872 	spin_unlock_irqrestore(&ata_scsi_rbuf_lock, *flags);
1873 }
1874 
1875 /**
1876  *	ata_scsi_rbuf_fill - wrapper for SCSI command simulators
1877  *	@args: device IDENTIFY data / SCSI command of interest.
1878  *	@actor: Callback hook for desired SCSI command simulator
1879  *
1880  *	Takes care of the hard work of simulating a SCSI command...
1881  *	Mapping the response buffer, calling the command's handler,
1882  *	and handling the handler's return value.  This return value
1883  *	indicates whether the handler wishes the SCSI command to be
1884  *	completed successfully (0), or not (in which case cmd->result
1885  *	and sense buffer are assumed to be set).
1886  *
1887  *	LOCKING:
1888  *	spin_lock_irqsave(host lock)
1889  */
1890 static void ata_scsi_rbuf_fill(struct ata_scsi_args *args,
1891 		unsigned int (*actor)(struct ata_scsi_args *args, u8 *rbuf))
1892 {
1893 	u8 *rbuf;
1894 	unsigned int rc;
1895 	struct scsi_cmnd *cmd = args->cmd;
1896 	unsigned long flags;
1897 
1898 	rbuf = ata_scsi_rbuf_get(cmd, false, &flags);
1899 	rc = actor(args, rbuf);
1900 	ata_scsi_rbuf_put(cmd, rc == 0, &flags);
1901 
1902 	if (rc == 0)
1903 		cmd->result = SAM_STAT_GOOD;
1904 	args->done(cmd);
1905 }
1906 
1907 /**
1908  *	ata_scsiop_inq_std - Simulate INQUIRY command
1909  *	@args: device IDENTIFY data / SCSI command of interest.
1910  *	@rbuf: Response buffer, to which simulated SCSI cmd output is sent.
1911  *
1912  *	Returns standard device identification data associated
1913  *	with non-VPD INQUIRY command output.
1914  *
1915  *	LOCKING:
1916  *	spin_lock_irqsave(host lock)
1917  */
1918 static unsigned int ata_scsiop_inq_std(struct ata_scsi_args *args, u8 *rbuf)
1919 {
1920 	const u8 versions[] = {
1921 		0x60,	/* SAM-3 (no version claimed) */
1922 
1923 		0x03,
1924 		0x20,	/* SBC-2 (no version claimed) */
1925 
1926 		0x02,
1927 		0x60	/* SPC-3 (no version claimed) */
1928 	};
1929 	u8 hdr[] = {
1930 		TYPE_DISK,
1931 		0,
1932 		0x5,	/* claim SPC-3 version compatibility */
1933 		2,
1934 		95 - 4
1935 	};
1936 
1937 	VPRINTK("ENTER\n");
1938 
1939 	/* set scsi removeable (RMB) bit per ata bit */
1940 	if (ata_id_removeable(args->id))
1941 		hdr[1] |= (1 << 7);
1942 
1943 	memcpy(rbuf, hdr, sizeof(hdr));
1944 	memcpy(&rbuf[8], "ATA     ", 8);
1945 	ata_id_string(args->id, &rbuf[16], ATA_ID_PROD, 16);
1946 	ata_id_string(args->id, &rbuf[32], ATA_ID_FW_REV, 4);
1947 
1948 	if (rbuf[32] == 0 || rbuf[32] == ' ')
1949 		memcpy(&rbuf[32], "n/a ", 4);
1950 
1951 	memcpy(rbuf + 59, versions, sizeof(versions));
1952 
1953 	return 0;
1954 }
1955 
1956 /**
1957  *	ata_scsiop_inq_00 - Simulate INQUIRY VPD page 0, list of pages
1958  *	@args: device IDENTIFY data / SCSI command of interest.
1959  *	@rbuf: Response buffer, to which simulated SCSI cmd output is sent.
1960  *
1961  *	Returns list of inquiry VPD pages available.
1962  *
1963  *	LOCKING:
1964  *	spin_lock_irqsave(host lock)
1965  */
1966 static unsigned int ata_scsiop_inq_00(struct ata_scsi_args *args, u8 *rbuf)
1967 {
1968 	const u8 pages[] = {
1969 		0x00,	/* page 0x00, this page */
1970 		0x80,	/* page 0x80, unit serial no page */
1971 		0x83,	/* page 0x83, device ident page */
1972 		0x89,	/* page 0x89, ata info page */
1973 		0xb0,	/* page 0xb0, block limits page */
1974 		0xb1,	/* page 0xb1, block device characteristics page */
1975 	};
1976 
1977 	rbuf[3] = sizeof(pages);	/* number of supported VPD pages */
1978 	memcpy(rbuf + 4, pages, sizeof(pages));
1979 	return 0;
1980 }
1981 
1982 /**
1983  *	ata_scsiop_inq_80 - Simulate INQUIRY VPD page 80, device serial number
1984  *	@args: device IDENTIFY data / SCSI command of interest.
1985  *	@rbuf: Response buffer, to which simulated SCSI cmd output is sent.
1986  *
1987  *	Returns ATA device serial number.
1988  *
1989  *	LOCKING:
1990  *	spin_lock_irqsave(host lock)
1991  */
1992 static unsigned int ata_scsiop_inq_80(struct ata_scsi_args *args, u8 *rbuf)
1993 {
1994 	const u8 hdr[] = {
1995 		0,
1996 		0x80,			/* this page code */
1997 		0,
1998 		ATA_ID_SERNO_LEN,	/* page len */
1999 	};
2000 
2001 	memcpy(rbuf, hdr, sizeof(hdr));
2002 	ata_id_string(args->id, (unsigned char *) &rbuf[4],
2003 		      ATA_ID_SERNO, ATA_ID_SERNO_LEN);
2004 	return 0;
2005 }
2006 
2007 /**
2008  *	ata_scsiop_inq_83 - Simulate INQUIRY VPD page 83, device identity
2009  *	@args: device IDENTIFY data / SCSI command of interest.
2010  *	@rbuf: Response buffer, to which simulated SCSI cmd output is sent.
2011  *
2012  *	Yields two logical unit device identification designators:
2013  *	 - vendor specific ASCII containing the ATA serial number
2014  *	 - SAT defined "t10 vendor id based" containing ASCII vendor
2015  *	   name ("ATA     "), model and serial numbers.
2016  *
2017  *	LOCKING:
2018  *	spin_lock_irqsave(host lock)
2019  */
2020 static unsigned int ata_scsiop_inq_83(struct ata_scsi_args *args, u8 *rbuf)
2021 {
2022 	const int sat_model_serial_desc_len = 68;
2023 	int num;
2024 
2025 	rbuf[1] = 0x83;			/* this page code */
2026 	num = 4;
2027 
2028 	/* piv=0, assoc=lu, code_set=ACSII, designator=vendor */
2029 	rbuf[num + 0] = 2;
2030 	rbuf[num + 3] = ATA_ID_SERNO_LEN;
2031 	num += 4;
2032 	ata_id_string(args->id, (unsigned char *) rbuf + num,
2033 		      ATA_ID_SERNO, ATA_ID_SERNO_LEN);
2034 	num += ATA_ID_SERNO_LEN;
2035 
2036 	/* SAT defined lu model and serial numbers descriptor */
2037 	/* piv=0, assoc=lu, code_set=ACSII, designator=t10 vendor id */
2038 	rbuf[num + 0] = 2;
2039 	rbuf[num + 1] = 1;
2040 	rbuf[num + 3] = sat_model_serial_desc_len;
2041 	num += 4;
2042 	memcpy(rbuf + num, "ATA     ", 8);
2043 	num += 8;
2044 	ata_id_string(args->id, (unsigned char *) rbuf + num, ATA_ID_PROD,
2045 		      ATA_ID_PROD_LEN);
2046 	num += ATA_ID_PROD_LEN;
2047 	ata_id_string(args->id, (unsigned char *) rbuf + num, ATA_ID_SERNO,
2048 		      ATA_ID_SERNO_LEN);
2049 	num += ATA_ID_SERNO_LEN;
2050 
2051 	rbuf[3] = num - 4;    /* page len (assume less than 256 bytes) */
2052 	return 0;
2053 }
2054 
2055 /**
2056  *	ata_scsiop_inq_89 - Simulate INQUIRY VPD page 89, ATA info
2057  *	@args: device IDENTIFY data / SCSI command of interest.
2058  *	@rbuf: Response buffer, to which simulated SCSI cmd output is sent.
2059  *
2060  *	Yields SAT-specified ATA VPD page.
2061  *
2062  *	LOCKING:
2063  *	spin_lock_irqsave(host lock)
2064  */
2065 static unsigned int ata_scsiop_inq_89(struct ata_scsi_args *args, u8 *rbuf)
2066 {
2067 	struct ata_taskfile tf;
2068 
2069 	memset(&tf, 0, sizeof(tf));
2070 
2071 	rbuf[1] = 0x89;			/* our page code */
2072 	rbuf[2] = (0x238 >> 8);		/* page size fixed at 238h */
2073 	rbuf[3] = (0x238 & 0xff);
2074 
2075 	memcpy(&rbuf[8], "linux   ", 8);
2076 	memcpy(&rbuf[16], "libata          ", 16);
2077 	memcpy(&rbuf[32], DRV_VERSION, 4);
2078 	ata_id_string(args->id, &rbuf[32], ATA_ID_FW_REV, 4);
2079 
2080 	/* we don't store the ATA device signature, so we fake it */
2081 
2082 	tf.command = ATA_DRDY;		/* really, this is Status reg */
2083 	tf.lbal = 0x1;
2084 	tf.nsect = 0x1;
2085 
2086 	ata_tf_to_fis(&tf, 0, 1, &rbuf[36]);	/* TODO: PMP? */
2087 	rbuf[36] = 0x34;		/* force D2H Reg FIS (34h) */
2088 
2089 	rbuf[56] = ATA_CMD_ID_ATA;
2090 
2091 	memcpy(&rbuf[60], &args->id[0], 512);
2092 	return 0;
2093 }
2094 
2095 static unsigned int ata_scsiop_inq_b0(struct ata_scsi_args *args, u8 *rbuf)
2096 {
2097 	u32 min_io_sectors;
2098 
2099 	rbuf[1] = 0xb0;
2100 	rbuf[3] = 0x3c;		/* required VPD size with unmap support */
2101 
2102 	/*
2103 	 * Optimal transfer length granularity.
2104 	 *
2105 	 * This is always one physical block, but for disks with a smaller
2106 	 * logical than physical sector size we need to figure out what the
2107 	 * latter is.
2108 	 */
2109 	if (ata_id_has_large_logical_sectors(args->id))
2110 		min_io_sectors = ata_id_logical_per_physical_sectors(args->id);
2111 	else
2112 		min_io_sectors = 1;
2113 	put_unaligned_be16(min_io_sectors, &rbuf[6]);
2114 
2115 	/*
2116 	 * Optimal unmap granularity.
2117 	 *
2118 	 * The ATA spec doesn't even know about a granularity or alignment
2119 	 * for the TRIM command.  We can leave away most of the unmap related
2120 	 * VPD page entries, but we have specifify a granularity to signal
2121 	 * that we support some form of unmap - in thise case via WRITE SAME
2122 	 * with the unmap bit set.
2123 	 */
2124 	if (ata_id_has_trim(args->id)) {
2125 		put_unaligned_be32(65535 * 512 / 8, &rbuf[20]);
2126 		put_unaligned_be32(1, &rbuf[28]);
2127 	}
2128 
2129 	return 0;
2130 }
2131 
2132 static unsigned int ata_scsiop_inq_b1(struct ata_scsi_args *args, u8 *rbuf)
2133 {
2134 	int form_factor = ata_id_form_factor(args->id);
2135 	int media_rotation_rate = ata_id_rotation_rate(args->id);
2136 
2137 	rbuf[1] = 0xb1;
2138 	rbuf[3] = 0x3c;
2139 	rbuf[4] = media_rotation_rate >> 8;
2140 	rbuf[5] = media_rotation_rate;
2141 	rbuf[7] = form_factor;
2142 
2143 	return 0;
2144 }
2145 
2146 /**
2147  *	ata_scsiop_noop - Command handler that simply returns success.
2148  *	@args: device IDENTIFY data / SCSI command of interest.
2149  *	@rbuf: Response buffer, to which simulated SCSI cmd output is sent.
2150  *
2151  *	No operation.  Simply returns success to caller, to indicate
2152  *	that the caller should successfully complete this SCSI command.
2153  *
2154  *	LOCKING:
2155  *	spin_lock_irqsave(host lock)
2156  */
2157 static unsigned int ata_scsiop_noop(struct ata_scsi_args *args, u8 *rbuf)
2158 {
2159 	VPRINTK("ENTER\n");
2160 	return 0;
2161 }
2162 
2163 /**
2164  *	ata_msense_caching - Simulate MODE SENSE caching info page
2165  *	@id: device IDENTIFY data
2166  *	@buf: output buffer
2167  *
2168  *	Generate a caching info page, which conditionally indicates
2169  *	write caching to the SCSI layer, depending on device
2170  *	capabilities.
2171  *
2172  *	LOCKING:
2173  *	None.
2174  */
2175 static unsigned int ata_msense_caching(u16 *id, u8 *buf)
2176 {
2177 	memcpy(buf, def_cache_mpage, sizeof(def_cache_mpage));
2178 	if (ata_id_wcache_enabled(id))
2179 		buf[2] |= (1 << 2);	/* write cache enable */
2180 	if (!ata_id_rahead_enabled(id))
2181 		buf[12] |= (1 << 5);	/* disable read ahead */
2182 	return sizeof(def_cache_mpage);
2183 }
2184 
2185 /**
2186  *	ata_msense_ctl_mode - Simulate MODE SENSE control mode page
2187  *	@buf: output buffer
2188  *
2189  *	Generate a generic MODE SENSE control mode page.
2190  *
2191  *	LOCKING:
2192  *	None.
2193  */
2194 static unsigned int ata_msense_ctl_mode(u8 *buf)
2195 {
2196 	memcpy(buf, def_control_mpage, sizeof(def_control_mpage));
2197 	return sizeof(def_control_mpage);
2198 }
2199 
2200 /**
2201  *	ata_msense_rw_recovery - Simulate MODE SENSE r/w error recovery page
2202  *	@buf: output buffer
2203  *
2204  *	Generate a generic MODE SENSE r/w error recovery page.
2205  *
2206  *	LOCKING:
2207  *	None.
2208  */
2209 static unsigned int ata_msense_rw_recovery(u8 *buf)
2210 {
2211 	memcpy(buf, def_rw_recovery_mpage, sizeof(def_rw_recovery_mpage));
2212 	return sizeof(def_rw_recovery_mpage);
2213 }
2214 
2215 /*
2216  * We can turn this into a real blacklist if it's needed, for now just
2217  * blacklist any Maxtor BANC1G10 revision firmware
2218  */
2219 static int ata_dev_supports_fua(u16 *id)
2220 {
2221 	unsigned char model[ATA_ID_PROD_LEN + 1], fw[ATA_ID_FW_REV_LEN + 1];
2222 
2223 	if (!libata_fua)
2224 		return 0;
2225 	if (!ata_id_has_fua(id))
2226 		return 0;
2227 
2228 	ata_id_c_string(id, model, ATA_ID_PROD, sizeof(model));
2229 	ata_id_c_string(id, fw, ATA_ID_FW_REV, sizeof(fw));
2230 
2231 	if (strcmp(model, "Maxtor"))
2232 		return 1;
2233 	if (strcmp(fw, "BANC1G10"))
2234 		return 1;
2235 
2236 	return 0; /* blacklisted */
2237 }
2238 
2239 /**
2240  *	ata_scsiop_mode_sense - Simulate MODE SENSE 6, 10 commands
2241  *	@args: device IDENTIFY data / SCSI command of interest.
2242  *	@rbuf: Response buffer, to which simulated SCSI cmd output is sent.
2243  *
2244  *	Simulate MODE SENSE commands. Assume this is invoked for direct
2245  *	access devices (e.g. disks) only. There should be no block
2246  *	descriptor for other device types.
2247  *
2248  *	LOCKING:
2249  *	spin_lock_irqsave(host lock)
2250  */
2251 static unsigned int ata_scsiop_mode_sense(struct ata_scsi_args *args, u8 *rbuf)
2252 {
2253 	struct ata_device *dev = args->dev;
2254 	u8 *scsicmd = args->cmd->cmnd, *p = rbuf;
2255 	const u8 sat_blk_desc[] = {
2256 		0, 0, 0, 0,	/* number of blocks: sat unspecified */
2257 		0,
2258 		0, 0x2, 0x0	/* block length: 512 bytes */
2259 	};
2260 	u8 pg, spg;
2261 	unsigned int ebd, page_control, six_byte;
2262 	u8 dpofua;
2263 
2264 	VPRINTK("ENTER\n");
2265 
2266 	six_byte = (scsicmd[0] == MODE_SENSE);
2267 	ebd = !(scsicmd[1] & 0x8);      /* dbd bit inverted == edb */
2268 	/*
2269 	 * LLBA bit in msense(10) ignored (compliant)
2270 	 */
2271 
2272 	page_control = scsicmd[2] >> 6;
2273 	switch (page_control) {
2274 	case 0: /* current */
2275 		break;  /* supported */
2276 	case 3: /* saved */
2277 		goto saving_not_supp;
2278 	case 1: /* changeable */
2279 	case 2: /* defaults */
2280 	default:
2281 		goto invalid_fld;
2282 	}
2283 
2284 	if (six_byte)
2285 		p += 4 + (ebd ? 8 : 0);
2286 	else
2287 		p += 8 + (ebd ? 8 : 0);
2288 
2289 	pg = scsicmd[2] & 0x3f;
2290 	spg = scsicmd[3];
2291 	/*
2292 	 * No mode subpages supported (yet) but asking for _all_
2293 	 * subpages may be valid
2294 	 */
2295 	if (spg && (spg != ALL_SUB_MPAGES))
2296 		goto invalid_fld;
2297 
2298 	switch(pg) {
2299 	case RW_RECOVERY_MPAGE:
2300 		p += ata_msense_rw_recovery(p);
2301 		break;
2302 
2303 	case CACHE_MPAGE:
2304 		p += ata_msense_caching(args->id, p);
2305 		break;
2306 
2307 	case CONTROL_MPAGE:
2308 		p += ata_msense_ctl_mode(p);
2309 		break;
2310 
2311 	case ALL_MPAGES:
2312 		p += ata_msense_rw_recovery(p);
2313 		p += ata_msense_caching(args->id, p);
2314 		p += ata_msense_ctl_mode(p);
2315 		break;
2316 
2317 	default:		/* invalid page code */
2318 		goto invalid_fld;
2319 	}
2320 
2321 	dpofua = 0;
2322 	if (ata_dev_supports_fua(args->id) && (dev->flags & ATA_DFLAG_LBA48) &&
2323 	    (!(dev->flags & ATA_DFLAG_PIO) || dev->multi_count))
2324 		dpofua = 1 << 4;
2325 
2326 	if (six_byte) {
2327 		rbuf[0] = p - rbuf - 1;
2328 		rbuf[2] |= dpofua;
2329 		if (ebd) {
2330 			rbuf[3] = sizeof(sat_blk_desc);
2331 			memcpy(rbuf + 4, sat_blk_desc, sizeof(sat_blk_desc));
2332 		}
2333 	} else {
2334 		unsigned int output_len = p - rbuf - 2;
2335 
2336 		rbuf[0] = output_len >> 8;
2337 		rbuf[1] = output_len;
2338 		rbuf[3] |= dpofua;
2339 		if (ebd) {
2340 			rbuf[7] = sizeof(sat_blk_desc);
2341 			memcpy(rbuf + 8, sat_blk_desc, sizeof(sat_blk_desc));
2342 		}
2343 	}
2344 	return 0;
2345 
2346 invalid_fld:
2347 	ata_scsi_set_sense(args->cmd, ILLEGAL_REQUEST, 0x24, 0x0);
2348 	/* "Invalid field in cbd" */
2349 	return 1;
2350 
2351 saving_not_supp:
2352 	ata_scsi_set_sense(args->cmd, ILLEGAL_REQUEST, 0x39, 0x0);
2353 	 /* "Saving parameters not supported" */
2354 	return 1;
2355 }
2356 
2357 /**
2358  *	ata_scsiop_read_cap - Simulate READ CAPACITY[ 16] commands
2359  *	@args: device IDENTIFY data / SCSI command of interest.
2360  *	@rbuf: Response buffer, to which simulated SCSI cmd output is sent.
2361  *
2362  *	Simulate READ CAPACITY commands.
2363  *
2364  *	LOCKING:
2365  *	None.
2366  */
2367 static unsigned int ata_scsiop_read_cap(struct ata_scsi_args *args, u8 *rbuf)
2368 {
2369 	struct ata_device *dev = args->dev;
2370 	u64 last_lba = dev->n_sectors - 1; /* LBA of the last block */
2371 	u8 log_per_phys = 0;
2372 	u16 lowest_aligned = 0;
2373 	u16 word_106 = dev->id[106];
2374 	u16 word_209 = dev->id[209];
2375 
2376 	if ((word_106 & 0xc000) == 0x4000) {
2377 		/* Number and offset of logical sectors per physical sector */
2378 		if (word_106 & (1 << 13))
2379 			log_per_phys = word_106 & 0xf;
2380 		if ((word_209 & 0xc000) == 0x4000) {
2381 			u16 first = dev->id[209] & 0x3fff;
2382 			if (first > 0)
2383 				lowest_aligned = (1 << log_per_phys) - first;
2384 		}
2385 	}
2386 
2387 	VPRINTK("ENTER\n");
2388 
2389 	if (args->cmd->cmnd[0] == READ_CAPACITY) {
2390 		if (last_lba >= 0xffffffffULL)
2391 			last_lba = 0xffffffff;
2392 
2393 		/* sector count, 32-bit */
2394 		rbuf[0] = last_lba >> (8 * 3);
2395 		rbuf[1] = last_lba >> (8 * 2);
2396 		rbuf[2] = last_lba >> (8 * 1);
2397 		rbuf[3] = last_lba;
2398 
2399 		/* sector size */
2400 		rbuf[6] = ATA_SECT_SIZE >> 8;
2401 		rbuf[7] = ATA_SECT_SIZE & 0xff;
2402 	} else {
2403 		/* sector count, 64-bit */
2404 		rbuf[0] = last_lba >> (8 * 7);
2405 		rbuf[1] = last_lba >> (8 * 6);
2406 		rbuf[2] = last_lba >> (8 * 5);
2407 		rbuf[3] = last_lba >> (8 * 4);
2408 		rbuf[4] = last_lba >> (8 * 3);
2409 		rbuf[5] = last_lba >> (8 * 2);
2410 		rbuf[6] = last_lba >> (8 * 1);
2411 		rbuf[7] = last_lba;
2412 
2413 		/* sector size */
2414 		rbuf[10] = ATA_SECT_SIZE >> 8;
2415 		rbuf[11] = ATA_SECT_SIZE & 0xff;
2416 
2417 		rbuf[12] = 0;
2418 		rbuf[13] = log_per_phys;
2419 		rbuf[14] = (lowest_aligned >> 8) & 0x3f;
2420 		rbuf[15] = lowest_aligned;
2421 
2422 		if (ata_id_has_trim(args->id)) {
2423 			rbuf[14] |= 0x80; /* TPE */
2424 
2425 			if (ata_id_has_zero_after_trim(args->id))
2426 				rbuf[14] |= 0x40; /* TPRZ */
2427 		}
2428 	}
2429 
2430 	return 0;
2431 }
2432 
2433 /**
2434  *	ata_scsiop_report_luns - Simulate REPORT LUNS command
2435  *	@args: device IDENTIFY data / SCSI command of interest.
2436  *	@rbuf: Response buffer, to which simulated SCSI cmd output is sent.
2437  *
2438  *	Simulate REPORT LUNS command.
2439  *
2440  *	LOCKING:
2441  *	spin_lock_irqsave(host lock)
2442  */
2443 static unsigned int ata_scsiop_report_luns(struct ata_scsi_args *args, u8 *rbuf)
2444 {
2445 	VPRINTK("ENTER\n");
2446 	rbuf[3] = 8;	/* just one lun, LUN 0, size 8 bytes */
2447 
2448 	return 0;
2449 }
2450 
2451 static void atapi_sense_complete(struct ata_queued_cmd *qc)
2452 {
2453 	if (qc->err_mask && ((qc->err_mask & AC_ERR_DEV) == 0)) {
2454 		/* FIXME: not quite right; we don't want the
2455 		 * translation of taskfile registers into
2456 		 * a sense descriptors, since that's only
2457 		 * correct for ATA, not ATAPI
2458 		 */
2459 		ata_gen_passthru_sense(qc);
2460 	}
2461 
2462 	qc->scsidone(qc->scsicmd);
2463 	ata_qc_free(qc);
2464 }
2465 
2466 /* is it pointless to prefer PIO for "safety reasons"? */
2467 static inline int ata_pio_use_silly(struct ata_port *ap)
2468 {
2469 	return (ap->flags & ATA_FLAG_PIO_DMA);
2470 }
2471 
2472 static void atapi_request_sense(struct ata_queued_cmd *qc)
2473 {
2474 	struct ata_port *ap = qc->ap;
2475 	struct scsi_cmnd *cmd = qc->scsicmd;
2476 
2477 	DPRINTK("ATAPI request sense\n");
2478 
2479 	/* FIXME: is this needed? */
2480 	memset(cmd->sense_buffer, 0, SCSI_SENSE_BUFFERSIZE);
2481 
2482 #ifdef CONFIG_ATA_SFF
2483 	if (ap->ops->sff_tf_read)
2484 		ap->ops->sff_tf_read(ap, &qc->tf);
2485 #endif
2486 
2487 	/* fill these in, for the case where they are -not- overwritten */
2488 	cmd->sense_buffer[0] = 0x70;
2489 	cmd->sense_buffer[2] = qc->tf.feature >> 4;
2490 
2491 	ata_qc_reinit(qc);
2492 
2493 	/* setup sg table and init transfer direction */
2494 	sg_init_one(&qc->sgent, cmd->sense_buffer, SCSI_SENSE_BUFFERSIZE);
2495 	ata_sg_init(qc, &qc->sgent, 1);
2496 	qc->dma_dir = DMA_FROM_DEVICE;
2497 
2498 	memset(&qc->cdb, 0, qc->dev->cdb_len);
2499 	qc->cdb[0] = REQUEST_SENSE;
2500 	qc->cdb[4] = SCSI_SENSE_BUFFERSIZE;
2501 
2502 	qc->tf.flags |= ATA_TFLAG_ISADDR | ATA_TFLAG_DEVICE;
2503 	qc->tf.command = ATA_CMD_PACKET;
2504 
2505 	if (ata_pio_use_silly(ap)) {
2506 		qc->tf.protocol = ATAPI_PROT_DMA;
2507 		qc->tf.feature |= ATAPI_PKT_DMA;
2508 	} else {
2509 		qc->tf.protocol = ATAPI_PROT_PIO;
2510 		qc->tf.lbam = SCSI_SENSE_BUFFERSIZE;
2511 		qc->tf.lbah = 0;
2512 	}
2513 	qc->nbytes = SCSI_SENSE_BUFFERSIZE;
2514 
2515 	qc->complete_fn = atapi_sense_complete;
2516 
2517 	ata_qc_issue(qc);
2518 
2519 	DPRINTK("EXIT\n");
2520 }
2521 
2522 static void atapi_qc_complete(struct ata_queued_cmd *qc)
2523 {
2524 	struct scsi_cmnd *cmd = qc->scsicmd;
2525 	unsigned int err_mask = qc->err_mask;
2526 
2527 	VPRINTK("ENTER, err_mask 0x%X\n", err_mask);
2528 
2529 	/* handle completion from new EH */
2530 	if (unlikely(qc->ap->ops->error_handler &&
2531 		     (err_mask || qc->flags & ATA_QCFLAG_SENSE_VALID))) {
2532 
2533 		if (!(qc->flags & ATA_QCFLAG_SENSE_VALID)) {
2534 			/* FIXME: not quite right; we don't want the
2535 			 * translation of taskfile registers into a
2536 			 * sense descriptors, since that's only
2537 			 * correct for ATA, not ATAPI
2538 			 */
2539 			ata_gen_passthru_sense(qc);
2540 		}
2541 
2542 		/* SCSI EH automatically locks door if sdev->locked is
2543 		 * set.  Sometimes door lock request continues to
2544 		 * fail, for example, when no media is present.  This
2545 		 * creates a loop - SCSI EH issues door lock which
2546 		 * fails and gets invoked again to acquire sense data
2547 		 * for the failed command.
2548 		 *
2549 		 * If door lock fails, always clear sdev->locked to
2550 		 * avoid this infinite loop.
2551 		 */
2552 		if (qc->cdb[0] == ALLOW_MEDIUM_REMOVAL)
2553 			qc->dev->sdev->locked = 0;
2554 
2555 		qc->scsicmd->result = SAM_STAT_CHECK_CONDITION;
2556 		qc->scsidone(cmd);
2557 		ata_qc_free(qc);
2558 		return;
2559 	}
2560 
2561 	/* successful completion or old EH failure path */
2562 	if (unlikely(err_mask & AC_ERR_DEV)) {
2563 		cmd->result = SAM_STAT_CHECK_CONDITION;
2564 		atapi_request_sense(qc);
2565 		return;
2566 	} else if (unlikely(err_mask)) {
2567 		/* FIXME: not quite right; we don't want the
2568 		 * translation of taskfile registers into
2569 		 * a sense descriptors, since that's only
2570 		 * correct for ATA, not ATAPI
2571 		 */
2572 		ata_gen_passthru_sense(qc);
2573 	} else {
2574 		u8 *scsicmd = cmd->cmnd;
2575 
2576 		if ((scsicmd[0] == INQUIRY) && ((scsicmd[1] & 0x03) == 0)) {
2577 			unsigned long flags;
2578 			u8 *buf;
2579 
2580 			buf = ata_scsi_rbuf_get(cmd, true, &flags);
2581 
2582 	/* ATAPI devices typically report zero for their SCSI version,
2583 	 * and sometimes deviate from the spec WRT response data
2584 	 * format.  If SCSI version is reported as zero like normal,
2585 	 * then we make the following fixups:  1) Fake MMC-5 version,
2586 	 * to indicate to the Linux scsi midlayer this is a modern
2587 	 * device.  2) Ensure response data format / ATAPI information
2588 	 * are always correct.
2589 	 */
2590 			if (buf[2] == 0) {
2591 				buf[2] = 0x5;
2592 				buf[3] = 0x32;
2593 			}
2594 
2595 			ata_scsi_rbuf_put(cmd, true, &flags);
2596 		}
2597 
2598 		cmd->result = SAM_STAT_GOOD;
2599 	}
2600 
2601 	qc->scsidone(cmd);
2602 	ata_qc_free(qc);
2603 }
2604 /**
2605  *	atapi_xlat - Initialize PACKET taskfile
2606  *	@qc: command structure to be initialized
2607  *
2608  *	LOCKING:
2609  *	spin_lock_irqsave(host lock)
2610  *
2611  *	RETURNS:
2612  *	Zero on success, non-zero on failure.
2613  */
2614 static unsigned int atapi_xlat(struct ata_queued_cmd *qc)
2615 {
2616 	struct scsi_cmnd *scmd = qc->scsicmd;
2617 	struct ata_device *dev = qc->dev;
2618 	int nodata = (scmd->sc_data_direction == DMA_NONE);
2619 	int using_pio = !nodata && (dev->flags & ATA_DFLAG_PIO);
2620 	unsigned int nbytes;
2621 
2622 	memset(qc->cdb, 0, dev->cdb_len);
2623 	memcpy(qc->cdb, scmd->cmnd, scmd->cmd_len);
2624 
2625 	qc->complete_fn = atapi_qc_complete;
2626 
2627 	qc->tf.flags |= ATA_TFLAG_ISADDR | ATA_TFLAG_DEVICE;
2628 	if (scmd->sc_data_direction == DMA_TO_DEVICE) {
2629 		qc->tf.flags |= ATA_TFLAG_WRITE;
2630 		DPRINTK("direction: write\n");
2631 	}
2632 
2633 	qc->tf.command = ATA_CMD_PACKET;
2634 	ata_qc_set_pc_nbytes(qc);
2635 
2636 	/* check whether ATAPI DMA is safe */
2637 	if (!nodata && !using_pio && atapi_check_dma(qc))
2638 		using_pio = 1;
2639 
2640 	/* Some controller variants snoop this value for Packet
2641 	 * transfers to do state machine and FIFO management.  Thus we
2642 	 * want to set it properly, and for DMA where it is
2643 	 * effectively meaningless.
2644 	 */
2645 	nbytes = min(ata_qc_raw_nbytes(qc), (unsigned int)63 * 1024);
2646 
2647 	/* Most ATAPI devices which honor transfer chunk size don't
2648 	 * behave according to the spec when odd chunk size which
2649 	 * matches the transfer length is specified.  If the number of
2650 	 * bytes to transfer is 2n+1.  According to the spec, what
2651 	 * should happen is to indicate that 2n+1 is going to be
2652 	 * transferred and transfer 2n+2 bytes where the last byte is
2653 	 * padding.
2654 	 *
2655 	 * In practice, this doesn't happen.  ATAPI devices first
2656 	 * indicate and transfer 2n bytes and then indicate and
2657 	 * transfer 2 bytes where the last byte is padding.
2658 	 *
2659 	 * This inconsistency confuses several controllers which
2660 	 * perform PIO using DMA such as Intel AHCIs and sil3124/32.
2661 	 * These controllers use actual number of transferred bytes to
2662 	 * update DMA poitner and transfer of 4n+2 bytes make those
2663 	 * controller push DMA pointer by 4n+4 bytes because SATA data
2664 	 * FISes are aligned to 4 bytes.  This causes data corruption
2665 	 * and buffer overrun.
2666 	 *
2667 	 * Always setting nbytes to even number solves this problem
2668 	 * because then ATAPI devices don't have to split data at 2n
2669 	 * boundaries.
2670 	 */
2671 	if (nbytes & 0x1)
2672 		nbytes++;
2673 
2674 	qc->tf.lbam = (nbytes & 0xFF);
2675 	qc->tf.lbah = (nbytes >> 8);
2676 
2677 	if (nodata)
2678 		qc->tf.protocol = ATAPI_PROT_NODATA;
2679 	else if (using_pio)
2680 		qc->tf.protocol = ATAPI_PROT_PIO;
2681 	else {
2682 		/* DMA data xfer */
2683 		qc->tf.protocol = ATAPI_PROT_DMA;
2684 		qc->tf.feature |= ATAPI_PKT_DMA;
2685 
2686 		if ((dev->flags & ATA_DFLAG_DMADIR) &&
2687 		    (scmd->sc_data_direction != DMA_TO_DEVICE))
2688 			/* some SATA bridges need us to indicate data xfer direction */
2689 			qc->tf.feature |= ATAPI_DMADIR;
2690 	}
2691 
2692 
2693 	/* FIXME: We need to translate 0x05 READ_BLOCK_LIMITS to a MODE_SENSE
2694 	   as ATAPI tape drives don't get this right otherwise */
2695 	return 0;
2696 }
2697 
2698 static struct ata_device *ata_find_dev(struct ata_port *ap, int devno)
2699 {
2700 	if (!sata_pmp_attached(ap)) {
2701 		if (likely(devno < ata_link_max_devices(&ap->link)))
2702 			return &ap->link.device[devno];
2703 	} else {
2704 		if (likely(devno < ap->nr_pmp_links))
2705 			return &ap->pmp_link[devno].device[0];
2706 	}
2707 
2708 	return NULL;
2709 }
2710 
2711 static struct ata_device *__ata_scsi_find_dev(struct ata_port *ap,
2712 					      const struct scsi_device *scsidev)
2713 {
2714 	int devno;
2715 
2716 	/* skip commands not addressed to targets we simulate */
2717 	if (!sata_pmp_attached(ap)) {
2718 		if (unlikely(scsidev->channel || scsidev->lun))
2719 			return NULL;
2720 		devno = scsidev->id;
2721 	} else {
2722 		if (unlikely(scsidev->id || scsidev->lun))
2723 			return NULL;
2724 		devno = scsidev->channel;
2725 	}
2726 
2727 	return ata_find_dev(ap, devno);
2728 }
2729 
2730 /**
2731  *	ata_scsi_find_dev - lookup ata_device from scsi_cmnd
2732  *	@ap: ATA port to which the device is attached
2733  *	@scsidev: SCSI device from which we derive the ATA device
2734  *
2735  *	Given various information provided in struct scsi_cmnd,
2736  *	map that onto an ATA bus, and using that mapping
2737  *	determine which ata_device is associated with the
2738  *	SCSI command to be sent.
2739  *
2740  *	LOCKING:
2741  *	spin_lock_irqsave(host lock)
2742  *
2743  *	RETURNS:
2744  *	Associated ATA device, or %NULL if not found.
2745  */
2746 static struct ata_device *
2747 ata_scsi_find_dev(struct ata_port *ap, const struct scsi_device *scsidev)
2748 {
2749 	struct ata_device *dev = __ata_scsi_find_dev(ap, scsidev);
2750 
2751 	if (unlikely(!dev || !ata_dev_enabled(dev)))
2752 		return NULL;
2753 
2754 	return dev;
2755 }
2756 
2757 /*
2758  *	ata_scsi_map_proto - Map pass-thru protocol value to taskfile value.
2759  *	@byte1: Byte 1 from pass-thru CDB.
2760  *
2761  *	RETURNS:
2762  *	ATA_PROT_UNKNOWN if mapping failed/unimplemented, protocol otherwise.
2763  */
2764 static u8
2765 ata_scsi_map_proto(u8 byte1)
2766 {
2767 	switch((byte1 & 0x1e) >> 1) {
2768 	case 3:		/* Non-data */
2769 		return ATA_PROT_NODATA;
2770 
2771 	case 6:		/* DMA */
2772 	case 10:	/* UDMA Data-in */
2773 	case 11:	/* UDMA Data-Out */
2774 		return ATA_PROT_DMA;
2775 
2776 	case 4:		/* PIO Data-in */
2777 	case 5:		/* PIO Data-out */
2778 		return ATA_PROT_PIO;
2779 
2780 	case 0:		/* Hard Reset */
2781 	case 1:		/* SRST */
2782 	case 8:		/* Device Diagnostic */
2783 	case 9:		/* Device Reset */
2784 	case 7:		/* DMA Queued */
2785 	case 12:	/* FPDMA */
2786 	case 15:	/* Return Response Info */
2787 	default:	/* Reserved */
2788 		break;
2789 	}
2790 
2791 	return ATA_PROT_UNKNOWN;
2792 }
2793 
2794 /**
2795  *	ata_scsi_pass_thru - convert ATA pass-thru CDB to taskfile
2796  *	@qc: command structure to be initialized
2797  *
2798  *	Handles either 12 or 16-byte versions of the CDB.
2799  *
2800  *	RETURNS:
2801  *	Zero on success, non-zero on failure.
2802  */
2803 static unsigned int ata_scsi_pass_thru(struct ata_queued_cmd *qc)
2804 {
2805 	struct ata_taskfile *tf = &(qc->tf);
2806 	struct scsi_cmnd *scmd = qc->scsicmd;
2807 	struct ata_device *dev = qc->dev;
2808 	const u8 *cdb = scmd->cmnd;
2809 
2810 	if ((tf->protocol = ata_scsi_map_proto(cdb[1])) == ATA_PROT_UNKNOWN)
2811 		goto invalid_fld;
2812 
2813 	/*
2814 	 * 12 and 16 byte CDBs use different offsets to
2815 	 * provide the various register values.
2816 	 */
2817 	if (cdb[0] == ATA_16) {
2818 		/*
2819 		 * 16-byte CDB - may contain extended commands.
2820 		 *
2821 		 * If that is the case, copy the upper byte register values.
2822 		 */
2823 		if (cdb[1] & 0x01) {
2824 			tf->hob_feature = cdb[3];
2825 			tf->hob_nsect = cdb[5];
2826 			tf->hob_lbal = cdb[7];
2827 			tf->hob_lbam = cdb[9];
2828 			tf->hob_lbah = cdb[11];
2829 			tf->flags |= ATA_TFLAG_LBA48;
2830 		} else
2831 			tf->flags &= ~ATA_TFLAG_LBA48;
2832 
2833 		/*
2834 		 * Always copy low byte, device and command registers.
2835 		 */
2836 		tf->feature = cdb[4];
2837 		tf->nsect = cdb[6];
2838 		tf->lbal = cdb[8];
2839 		tf->lbam = cdb[10];
2840 		tf->lbah = cdb[12];
2841 		tf->device = cdb[13];
2842 		tf->command = cdb[14];
2843 	} else {
2844 		/*
2845 		 * 12-byte CDB - incapable of extended commands.
2846 		 */
2847 		tf->flags &= ~ATA_TFLAG_LBA48;
2848 
2849 		tf->feature = cdb[3];
2850 		tf->nsect = cdb[4];
2851 		tf->lbal = cdb[5];
2852 		tf->lbam = cdb[6];
2853 		tf->lbah = cdb[7];
2854 		tf->device = cdb[8];
2855 		tf->command = cdb[9];
2856 	}
2857 
2858 	/* enforce correct master/slave bit */
2859 	tf->device = dev->devno ?
2860 		tf->device | ATA_DEV1 : tf->device & ~ATA_DEV1;
2861 
2862 	/* READ/WRITE LONG use a non-standard sect_size */
2863 	qc->sect_size = ATA_SECT_SIZE;
2864 	switch (tf->command) {
2865 	case ATA_CMD_READ_LONG:
2866 	case ATA_CMD_READ_LONG_ONCE:
2867 	case ATA_CMD_WRITE_LONG:
2868 	case ATA_CMD_WRITE_LONG_ONCE:
2869 		if (tf->protocol != ATA_PROT_PIO || tf->nsect != 1)
2870 			goto invalid_fld;
2871 		qc->sect_size = scsi_bufflen(scmd);
2872 	}
2873 
2874 	/*
2875 	 * Set flags so that all registers will be written, pass on
2876 	 * write indication (used for PIO/DMA setup), result TF is
2877 	 * copied back and we don't whine too much about its failure.
2878 	 */
2879 	tf->flags |= ATA_TFLAG_ISADDR | ATA_TFLAG_DEVICE;
2880 	if (scmd->sc_data_direction == DMA_TO_DEVICE)
2881 		tf->flags |= ATA_TFLAG_WRITE;
2882 
2883 	qc->flags |= ATA_QCFLAG_RESULT_TF | ATA_QCFLAG_QUIET;
2884 
2885 	/*
2886 	 * Set transfer length.
2887 	 *
2888 	 * TODO: find out if we need to do more here to
2889 	 *       cover scatter/gather case.
2890 	 */
2891 	ata_qc_set_pc_nbytes(qc);
2892 
2893 	/* We may not issue DMA commands if no DMA mode is set */
2894 	if (tf->protocol == ATA_PROT_DMA && dev->dma_mode == 0)
2895 		goto invalid_fld;
2896 
2897 	/* sanity check for pio multi commands */
2898 	if ((cdb[1] & 0xe0) && !is_multi_taskfile(tf))
2899 		goto invalid_fld;
2900 
2901 	if (is_multi_taskfile(tf)) {
2902 		unsigned int multi_count = 1 << (cdb[1] >> 5);
2903 
2904 		/* compare the passed through multi_count
2905 		 * with the cached multi_count of libata
2906 		 */
2907 		if (multi_count != dev->multi_count)
2908 			ata_dev_printk(dev, KERN_WARNING,
2909 				       "invalid multi_count %u ignored\n",
2910 				       multi_count);
2911 	}
2912 
2913 	/*
2914 	 * Filter SET_FEATURES - XFER MODE command -- otherwise,
2915 	 * SET_FEATURES - XFER MODE must be preceded/succeeded
2916 	 * by an update to hardware-specific registers for each
2917 	 * controller (i.e. the reason for ->set_piomode(),
2918 	 * ->set_dmamode(), and ->post_set_mode() hooks).
2919 	 */
2920 	if (tf->command == ATA_CMD_SET_FEATURES &&
2921 	    tf->feature == SETFEATURES_XFER)
2922 		goto invalid_fld;
2923 
2924 	/*
2925 	 * Filter TPM commands by default. These provide an
2926 	 * essentially uncontrolled encrypted "back door" between
2927 	 * applications and the disk. Set libata.allow_tpm=1 if you
2928 	 * have a real reason for wanting to use them. This ensures
2929 	 * that installed software cannot easily mess stuff up without
2930 	 * user intent. DVR type users will probably ship with this enabled
2931 	 * for movie content management.
2932 	 *
2933 	 * Note that for ATA8 we can issue a DCS change and DCS freeze lock
2934 	 * for this and should do in future but that it is not sufficient as
2935 	 * DCS is an optional feature set. Thus we also do the software filter
2936 	 * so that we comply with the TC consortium stated goal that the user
2937 	 * can turn off TC features of their system.
2938 	 */
2939 	if (tf->command >= 0x5C && tf->command <= 0x5F && !libata_allow_tpm)
2940 		goto invalid_fld;
2941 
2942 	return 0;
2943 
2944  invalid_fld:
2945 	ata_scsi_set_sense(scmd, ILLEGAL_REQUEST, 0x24, 0x00);
2946 	/* "Invalid field in cdb" */
2947 	return 1;
2948 }
2949 
2950 static unsigned int ata_scsi_write_same_xlat(struct ata_queued_cmd *qc)
2951 {
2952 	struct ata_taskfile *tf = &qc->tf;
2953 	struct scsi_cmnd *scmd = qc->scsicmd;
2954 	struct ata_device *dev = qc->dev;
2955 	const u8 *cdb = scmd->cmnd;
2956 	u64 block;
2957 	u32 n_block;
2958 	u32 size;
2959 	void *buf;
2960 
2961 	/* we may not issue DMA commands if no DMA mode is set */
2962 	if (unlikely(!dev->dma_mode))
2963 		goto invalid_fld;
2964 
2965 	if (unlikely(scmd->cmd_len < 16))
2966 		goto invalid_fld;
2967 	scsi_16_lba_len(cdb, &block, &n_block);
2968 
2969 	/* for now we only support WRITE SAME with the unmap bit set */
2970 	if (unlikely(!(cdb[1] & 0x8)))
2971 		goto invalid_fld;
2972 
2973 	/*
2974 	 * WRITE SAME always has a sector sized buffer as payload, this
2975 	 * should never be a multiple entry S/G list.
2976 	 */
2977 	if (!scsi_sg_count(scmd))
2978 		goto invalid_fld;
2979 
2980 	buf = page_address(sg_page(scsi_sglist(scmd)));
2981 	size = ata_set_lba_range_entries(buf, 512, block, n_block);
2982 
2983 	tf->protocol = ATA_PROT_DMA;
2984 	tf->hob_feature = 0;
2985 	tf->feature = ATA_DSM_TRIM;
2986 	tf->hob_nsect = (size / 512) >> 8;
2987 	tf->nsect = size / 512;
2988 	tf->command = ATA_CMD_DSM;
2989 	tf->flags |= ATA_TFLAG_ISADDR | ATA_TFLAG_DEVICE | ATA_TFLAG_LBA48 |
2990 		     ATA_TFLAG_WRITE;
2991 
2992 	ata_qc_set_pc_nbytes(qc);
2993 
2994 	return 0;
2995 
2996  invalid_fld:
2997 	ata_scsi_set_sense(scmd, ILLEGAL_REQUEST, 0x24, 0x00);
2998 	/* "Invalid field in cdb" */
2999 	return 1;
3000 }
3001 
3002 /**
3003  *	ata_get_xlat_func - check if SCSI to ATA translation is possible
3004  *	@dev: ATA device
3005  *	@cmd: SCSI command opcode to consider
3006  *
3007  *	Look up the SCSI command given, and determine whether the
3008  *	SCSI command is to be translated or simulated.
3009  *
3010  *	RETURNS:
3011  *	Pointer to translation function if possible, %NULL if not.
3012  */
3013 
3014 static inline ata_xlat_func_t ata_get_xlat_func(struct ata_device *dev, u8 cmd)
3015 {
3016 	switch (cmd) {
3017 	case READ_6:
3018 	case READ_10:
3019 	case READ_16:
3020 
3021 	case WRITE_6:
3022 	case WRITE_10:
3023 	case WRITE_16:
3024 		return ata_scsi_rw_xlat;
3025 
3026 	case WRITE_SAME_16:
3027 		return ata_scsi_write_same_xlat;
3028 
3029 	case SYNCHRONIZE_CACHE:
3030 		if (ata_try_flush_cache(dev))
3031 			return ata_scsi_flush_xlat;
3032 		break;
3033 
3034 	case VERIFY:
3035 	case VERIFY_16:
3036 		return ata_scsi_verify_xlat;
3037 
3038 	case ATA_12:
3039 	case ATA_16:
3040 		return ata_scsi_pass_thru;
3041 
3042 	case START_STOP:
3043 		return ata_scsi_start_stop_xlat;
3044 	}
3045 
3046 	return NULL;
3047 }
3048 
3049 /**
3050  *	ata_scsi_dump_cdb - dump SCSI command contents to dmesg
3051  *	@ap: ATA port to which the command was being sent
3052  *	@cmd: SCSI command to dump
3053  *
3054  *	Prints the contents of a SCSI command via printk().
3055  */
3056 
3057 static inline void ata_scsi_dump_cdb(struct ata_port *ap,
3058 				     struct scsi_cmnd *cmd)
3059 {
3060 #ifdef ATA_DEBUG
3061 	struct scsi_device *scsidev = cmd->device;
3062 	u8 *scsicmd = cmd->cmnd;
3063 
3064 	DPRINTK("CDB (%u:%d,%d,%d) %02x %02x %02x %02x %02x %02x %02x %02x %02x\n",
3065 		ap->print_id,
3066 		scsidev->channel, scsidev->id, scsidev->lun,
3067 		scsicmd[0], scsicmd[1], scsicmd[2], scsicmd[3],
3068 		scsicmd[4], scsicmd[5], scsicmd[6], scsicmd[7],
3069 		scsicmd[8]);
3070 #endif
3071 }
3072 
3073 static inline int __ata_scsi_queuecmd(struct scsi_cmnd *scmd,
3074 				      void (*done)(struct scsi_cmnd *),
3075 				      struct ata_device *dev)
3076 {
3077 	u8 scsi_op = scmd->cmnd[0];
3078 	ata_xlat_func_t xlat_func;
3079 	int rc = 0;
3080 
3081 	if (dev->class == ATA_DEV_ATA) {
3082 		if (unlikely(!scmd->cmd_len || scmd->cmd_len > dev->cdb_len))
3083 			goto bad_cdb_len;
3084 
3085 		xlat_func = ata_get_xlat_func(dev, scsi_op);
3086 	} else {
3087 		if (unlikely(!scmd->cmd_len))
3088 			goto bad_cdb_len;
3089 
3090 		xlat_func = NULL;
3091 		if (likely((scsi_op != ATA_16) || !atapi_passthru16)) {
3092 			/* relay SCSI command to ATAPI device */
3093 			int len = COMMAND_SIZE(scsi_op);
3094 			if (unlikely(len > scmd->cmd_len || len > dev->cdb_len))
3095 				goto bad_cdb_len;
3096 
3097 			xlat_func = atapi_xlat;
3098 		} else {
3099 			/* ATA_16 passthru, treat as an ATA command */
3100 			if (unlikely(scmd->cmd_len > 16))
3101 				goto bad_cdb_len;
3102 
3103 			xlat_func = ata_get_xlat_func(dev, scsi_op);
3104 		}
3105 	}
3106 
3107 	if (xlat_func)
3108 		rc = ata_scsi_translate(dev, scmd, done, xlat_func);
3109 	else
3110 		ata_scsi_simulate(dev, scmd, done);
3111 
3112 	return rc;
3113 
3114  bad_cdb_len:
3115 	DPRINTK("bad CDB len=%u, scsi_op=0x%02x, max=%u\n",
3116 		scmd->cmd_len, scsi_op, dev->cdb_len);
3117 	scmd->result = DID_ERROR << 16;
3118 	done(scmd);
3119 	return 0;
3120 }
3121 
3122 /**
3123  *	ata_scsi_queuecmd - Issue SCSI cdb to libata-managed device
3124  *	@cmd: SCSI command to be sent
3125  *	@done: Completion function, called when command is complete
3126  *
3127  *	In some cases, this function translates SCSI commands into
3128  *	ATA taskfiles, and queues the taskfiles to be sent to
3129  *	hardware.  In other cases, this function simulates a
3130  *	SCSI device by evaluating and responding to certain
3131  *	SCSI commands.  This creates the overall effect of
3132  *	ATA and ATAPI devices appearing as SCSI devices.
3133  *
3134  *	LOCKING:
3135  *	Releases scsi-layer-held lock, and obtains host lock.
3136  *
3137  *	RETURNS:
3138  *	Return value from __ata_scsi_queuecmd() if @cmd can be queued,
3139  *	0 otherwise.
3140  */
3141 int ata_scsi_queuecmd(struct scsi_cmnd *cmd, void (*done)(struct scsi_cmnd *))
3142 {
3143 	struct ata_port *ap;
3144 	struct ata_device *dev;
3145 	struct scsi_device *scsidev = cmd->device;
3146 	struct Scsi_Host *shost = scsidev->host;
3147 	int rc = 0;
3148 
3149 	ap = ata_shost_to_port(shost);
3150 
3151 	spin_unlock(shost->host_lock);
3152 	spin_lock(ap->lock);
3153 
3154 	ata_scsi_dump_cdb(ap, cmd);
3155 
3156 	dev = ata_scsi_find_dev(ap, scsidev);
3157 	if (likely(dev))
3158 		rc = __ata_scsi_queuecmd(cmd, done, dev);
3159 	else {
3160 		cmd->result = (DID_BAD_TARGET << 16);
3161 		done(cmd);
3162 	}
3163 
3164 	spin_unlock(ap->lock);
3165 	spin_lock(shost->host_lock);
3166 	return rc;
3167 }
3168 
3169 /**
3170  *	ata_scsi_simulate - simulate SCSI command on ATA device
3171  *	@dev: the target device
3172  *	@cmd: SCSI command being sent to device.
3173  *	@done: SCSI command completion function.
3174  *
3175  *	Interprets and directly executes a select list of SCSI commands
3176  *	that can be handled internally.
3177  *
3178  *	LOCKING:
3179  *	spin_lock_irqsave(host lock)
3180  */
3181 
3182 void ata_scsi_simulate(struct ata_device *dev, struct scsi_cmnd *cmd,
3183 		      void (*done)(struct scsi_cmnd *))
3184 {
3185 	struct ata_scsi_args args;
3186 	const u8 *scsicmd = cmd->cmnd;
3187 	u8 tmp8;
3188 
3189 	args.dev = dev;
3190 	args.id = dev->id;
3191 	args.cmd = cmd;
3192 	args.done = done;
3193 
3194 	switch(scsicmd[0]) {
3195 	/* TODO: worth improving? */
3196 	case FORMAT_UNIT:
3197 		ata_scsi_invalid_field(cmd, done);
3198 		break;
3199 
3200 	case INQUIRY:
3201 		if (scsicmd[1] & 2)	           /* is CmdDt set?  */
3202 			ata_scsi_invalid_field(cmd, done);
3203 		else if ((scsicmd[1] & 1) == 0)    /* is EVPD clear? */
3204 			ata_scsi_rbuf_fill(&args, ata_scsiop_inq_std);
3205 		else switch (scsicmd[2]) {
3206 		case 0x00:
3207 			ata_scsi_rbuf_fill(&args, ata_scsiop_inq_00);
3208 			break;
3209 		case 0x80:
3210 			ata_scsi_rbuf_fill(&args, ata_scsiop_inq_80);
3211 			break;
3212 		case 0x83:
3213 			ata_scsi_rbuf_fill(&args, ata_scsiop_inq_83);
3214 			break;
3215 		case 0x89:
3216 			ata_scsi_rbuf_fill(&args, ata_scsiop_inq_89);
3217 			break;
3218 		case 0xb0:
3219 			ata_scsi_rbuf_fill(&args, ata_scsiop_inq_b0);
3220 			break;
3221 		case 0xb1:
3222 			ata_scsi_rbuf_fill(&args, ata_scsiop_inq_b1);
3223 			break;
3224 		default:
3225 			ata_scsi_invalid_field(cmd, done);
3226 			break;
3227 		}
3228 		break;
3229 
3230 	case MODE_SENSE:
3231 	case MODE_SENSE_10:
3232 		ata_scsi_rbuf_fill(&args, ata_scsiop_mode_sense);
3233 		break;
3234 
3235 	case MODE_SELECT:	/* unconditionally return */
3236 	case MODE_SELECT_10:	/* bad-field-in-cdb */
3237 		ata_scsi_invalid_field(cmd, done);
3238 		break;
3239 
3240 	case READ_CAPACITY:
3241 		ata_scsi_rbuf_fill(&args, ata_scsiop_read_cap);
3242 		break;
3243 
3244 	case SERVICE_ACTION_IN:
3245 		if ((scsicmd[1] & 0x1f) == SAI_READ_CAPACITY_16)
3246 			ata_scsi_rbuf_fill(&args, ata_scsiop_read_cap);
3247 		else
3248 			ata_scsi_invalid_field(cmd, done);
3249 		break;
3250 
3251 	case REPORT_LUNS:
3252 		ata_scsi_rbuf_fill(&args, ata_scsiop_report_luns);
3253 		break;
3254 
3255 	case REQUEST_SENSE:
3256 		ata_scsi_set_sense(cmd, 0, 0, 0);
3257 		cmd->result = (DRIVER_SENSE << 24);
3258 		done(cmd);
3259 		break;
3260 
3261 	/* if we reach this, then writeback caching is disabled,
3262 	 * turning this into a no-op.
3263 	 */
3264 	case SYNCHRONIZE_CACHE:
3265 		/* fall through */
3266 
3267 	/* no-op's, complete with success */
3268 	case REZERO_UNIT:
3269 	case SEEK_6:
3270 	case SEEK_10:
3271 	case TEST_UNIT_READY:
3272 		ata_scsi_rbuf_fill(&args, ata_scsiop_noop);
3273 		break;
3274 
3275 	case SEND_DIAGNOSTIC:
3276 		tmp8 = scsicmd[1] & ~(1 << 3);
3277 		if ((tmp8 == 0x4) && (!scsicmd[3]) && (!scsicmd[4]))
3278 			ata_scsi_rbuf_fill(&args, ata_scsiop_noop);
3279 		else
3280 			ata_scsi_invalid_field(cmd, done);
3281 		break;
3282 
3283 	/* all other commands */
3284 	default:
3285 		ata_scsi_set_sense(cmd, ILLEGAL_REQUEST, 0x20, 0x0);
3286 		/* "Invalid command operation code" */
3287 		done(cmd);
3288 		break;
3289 	}
3290 }
3291 
3292 int ata_scsi_add_hosts(struct ata_host *host, struct scsi_host_template *sht)
3293 {
3294 	int i, rc;
3295 
3296 	for (i = 0; i < host->n_ports; i++) {
3297 		struct ata_port *ap = host->ports[i];
3298 		struct Scsi_Host *shost;
3299 
3300 		rc = -ENOMEM;
3301 		shost = scsi_host_alloc(sht, sizeof(struct ata_port *));
3302 		if (!shost)
3303 			goto err_alloc;
3304 
3305 		*(struct ata_port **)&shost->hostdata[0] = ap;
3306 		ap->scsi_host = shost;
3307 
3308 		shost->transportt = &ata_scsi_transport_template;
3309 		shost->unique_id = ap->print_id;
3310 		shost->max_id = 16;
3311 		shost->max_lun = 1;
3312 		shost->max_channel = 1;
3313 		shost->max_cmd_len = 16;
3314 
3315 		/* Schedule policy is determined by ->qc_defer()
3316 		 * callback and it needs to see every deferred qc.
3317 		 * Set host_blocked to 1 to prevent SCSI midlayer from
3318 		 * automatically deferring requests.
3319 		 */
3320 		shost->max_host_blocked = 1;
3321 
3322 		rc = scsi_add_host(ap->scsi_host, ap->host->dev);
3323 		if (rc)
3324 			goto err_add;
3325 	}
3326 
3327 	return 0;
3328 
3329  err_add:
3330 	scsi_host_put(host->ports[i]->scsi_host);
3331  err_alloc:
3332 	while (--i >= 0) {
3333 		struct Scsi_Host *shost = host->ports[i]->scsi_host;
3334 
3335 		scsi_remove_host(shost);
3336 		scsi_host_put(shost);
3337 	}
3338 	return rc;
3339 }
3340 
3341 void ata_scsi_scan_host(struct ata_port *ap, int sync)
3342 {
3343 	int tries = 5;
3344 	struct ata_device *last_failed_dev = NULL;
3345 	struct ata_link *link;
3346 	struct ata_device *dev;
3347 
3348  repeat:
3349 	ata_for_each_link(link, ap, EDGE) {
3350 		ata_for_each_dev(dev, link, ENABLED) {
3351 			struct scsi_device *sdev;
3352 			int channel = 0, id = 0;
3353 
3354 			if (dev->sdev)
3355 				continue;
3356 
3357 			if (ata_is_host_link(link))
3358 				id = dev->devno;
3359 			else
3360 				channel = link->pmp;
3361 
3362 			sdev = __scsi_add_device(ap->scsi_host, channel, id, 0,
3363 						 NULL);
3364 			if (!IS_ERR(sdev)) {
3365 				dev->sdev = sdev;
3366 				scsi_device_put(sdev);
3367 			}
3368 		}
3369 	}
3370 
3371 	/* If we scanned while EH was in progress or allocation
3372 	 * failure occurred, scan would have failed silently.  Check
3373 	 * whether all devices are attached.
3374 	 */
3375 	ata_for_each_link(link, ap, EDGE) {
3376 		ata_for_each_dev(dev, link, ENABLED) {
3377 			if (!dev->sdev)
3378 				goto exit_loop;
3379 		}
3380 	}
3381  exit_loop:
3382 	if (!link)
3383 		return;
3384 
3385 	/* we're missing some SCSI devices */
3386 	if (sync) {
3387 		/* If caller requested synchrnous scan && we've made
3388 		 * any progress, sleep briefly and repeat.
3389 		 */
3390 		if (dev != last_failed_dev) {
3391 			msleep(100);
3392 			last_failed_dev = dev;
3393 			goto repeat;
3394 		}
3395 
3396 		/* We might be failing to detect boot device, give it
3397 		 * a few more chances.
3398 		 */
3399 		if (--tries) {
3400 			msleep(100);
3401 			goto repeat;
3402 		}
3403 
3404 		ata_port_printk(ap, KERN_ERR, "WARNING: synchronous SCSI scan "
3405 				"failed without making any progress,\n"
3406 				"                  switching to async\n");
3407 	}
3408 
3409 	queue_delayed_work(ata_aux_wq, &ap->hotplug_task,
3410 			   round_jiffies_relative(HZ));
3411 }
3412 
3413 /**
3414  *	ata_scsi_offline_dev - offline attached SCSI device
3415  *	@dev: ATA device to offline attached SCSI device for
3416  *
3417  *	This function is called from ata_eh_hotplug() and responsible
3418  *	for taking the SCSI device attached to @dev offline.  This
3419  *	function is called with host lock which protects dev->sdev
3420  *	against clearing.
3421  *
3422  *	LOCKING:
3423  *	spin_lock_irqsave(host lock)
3424  *
3425  *	RETURNS:
3426  *	1 if attached SCSI device exists, 0 otherwise.
3427  */
3428 int ata_scsi_offline_dev(struct ata_device *dev)
3429 {
3430 	if (dev->sdev) {
3431 		scsi_device_set_state(dev->sdev, SDEV_OFFLINE);
3432 		return 1;
3433 	}
3434 	return 0;
3435 }
3436 
3437 /**
3438  *	ata_scsi_remove_dev - remove attached SCSI device
3439  *	@dev: ATA device to remove attached SCSI device for
3440  *
3441  *	This function is called from ata_eh_scsi_hotplug() and
3442  *	responsible for removing the SCSI device attached to @dev.
3443  *
3444  *	LOCKING:
3445  *	Kernel thread context (may sleep).
3446  */
3447 static void ata_scsi_remove_dev(struct ata_device *dev)
3448 {
3449 	struct ata_port *ap = dev->link->ap;
3450 	struct scsi_device *sdev;
3451 	unsigned long flags;
3452 
3453 	/* Alas, we need to grab scan_mutex to ensure SCSI device
3454 	 * state doesn't change underneath us and thus
3455 	 * scsi_device_get() always succeeds.  The mutex locking can
3456 	 * be removed if there is __scsi_device_get() interface which
3457 	 * increments reference counts regardless of device state.
3458 	 */
3459 	mutex_lock(&ap->scsi_host->scan_mutex);
3460 	spin_lock_irqsave(ap->lock, flags);
3461 
3462 	/* clearing dev->sdev is protected by host lock */
3463 	sdev = dev->sdev;
3464 	dev->sdev = NULL;
3465 
3466 	if (sdev) {
3467 		/* If user initiated unplug races with us, sdev can go
3468 		 * away underneath us after the host lock and
3469 		 * scan_mutex are released.  Hold onto it.
3470 		 */
3471 		if (scsi_device_get(sdev) == 0) {
3472 			/* The following ensures the attached sdev is
3473 			 * offline on return from ata_scsi_offline_dev()
3474 			 * regardless it wins or loses the race
3475 			 * against this function.
3476 			 */
3477 			scsi_device_set_state(sdev, SDEV_OFFLINE);
3478 		} else {
3479 			WARN_ON(1);
3480 			sdev = NULL;
3481 		}
3482 	}
3483 
3484 	spin_unlock_irqrestore(ap->lock, flags);
3485 	mutex_unlock(&ap->scsi_host->scan_mutex);
3486 
3487 	if (sdev) {
3488 		ata_dev_printk(dev, KERN_INFO, "detaching (SCSI %s)\n",
3489 			       dev_name(&sdev->sdev_gendev));
3490 
3491 		scsi_remove_device(sdev);
3492 		scsi_device_put(sdev);
3493 	}
3494 }
3495 
3496 static void ata_scsi_handle_link_detach(struct ata_link *link)
3497 {
3498 	struct ata_port *ap = link->ap;
3499 	struct ata_device *dev;
3500 
3501 	ata_for_each_dev(dev, link, ALL) {
3502 		unsigned long flags;
3503 
3504 		if (!(dev->flags & ATA_DFLAG_DETACHED))
3505 			continue;
3506 
3507 		spin_lock_irqsave(ap->lock, flags);
3508 		dev->flags &= ~ATA_DFLAG_DETACHED;
3509 		spin_unlock_irqrestore(ap->lock, flags);
3510 
3511 		ata_scsi_remove_dev(dev);
3512 	}
3513 }
3514 
3515 /**
3516  *	ata_scsi_media_change_notify - send media change event
3517  *	@dev: Pointer to the disk device with media change event
3518  *
3519  *	Tell the block layer to send a media change notification
3520  *	event.
3521  *
3522  * 	LOCKING:
3523  * 	spin_lock_irqsave(host lock)
3524  */
3525 void ata_scsi_media_change_notify(struct ata_device *dev)
3526 {
3527 	if (dev->sdev)
3528 		sdev_evt_send_simple(dev->sdev, SDEV_EVT_MEDIA_CHANGE,
3529 				     GFP_ATOMIC);
3530 }
3531 
3532 /**
3533  *	ata_scsi_hotplug - SCSI part of hotplug
3534  *	@work: Pointer to ATA port to perform SCSI hotplug on
3535  *
3536  *	Perform SCSI part of hotplug.  It's executed from a separate
3537  *	workqueue after EH completes.  This is necessary because SCSI
3538  *	hot plugging requires working EH and hot unplugging is
3539  *	synchronized with hot plugging with a mutex.
3540  *
3541  *	LOCKING:
3542  *	Kernel thread context (may sleep).
3543  */
3544 void ata_scsi_hotplug(struct work_struct *work)
3545 {
3546 	struct ata_port *ap =
3547 		container_of(work, struct ata_port, hotplug_task.work);
3548 	int i;
3549 
3550 	if (ap->pflags & ATA_PFLAG_UNLOADING) {
3551 		DPRINTK("ENTER/EXIT - unloading\n");
3552 		return;
3553 	}
3554 
3555 	DPRINTK("ENTER\n");
3556 
3557 	/* Unplug detached devices.  We cannot use link iterator here
3558 	 * because PMP links have to be scanned even if PMP is
3559 	 * currently not attached.  Iterate manually.
3560 	 */
3561 	ata_scsi_handle_link_detach(&ap->link);
3562 	if (ap->pmp_link)
3563 		for (i = 0; i < SATA_PMP_MAX_PORTS; i++)
3564 			ata_scsi_handle_link_detach(&ap->pmp_link[i]);
3565 
3566 	/* scan for new ones */
3567 	ata_scsi_scan_host(ap, 0);
3568 
3569 	DPRINTK("EXIT\n");
3570 }
3571 
3572 /**
3573  *	ata_scsi_user_scan - indication for user-initiated bus scan
3574  *	@shost: SCSI host to scan
3575  *	@channel: Channel to scan
3576  *	@id: ID to scan
3577  *	@lun: LUN to scan
3578  *
3579  *	This function is called when user explicitly requests bus
3580  *	scan.  Set probe pending flag and invoke EH.
3581  *
3582  *	LOCKING:
3583  *	SCSI layer (we don't care)
3584  *
3585  *	RETURNS:
3586  *	Zero.
3587  */
3588 static int ata_scsi_user_scan(struct Scsi_Host *shost, unsigned int channel,
3589 			      unsigned int id, unsigned int lun)
3590 {
3591 	struct ata_port *ap = ata_shost_to_port(shost);
3592 	unsigned long flags;
3593 	int devno, rc = 0;
3594 
3595 	if (!ap->ops->error_handler)
3596 		return -EOPNOTSUPP;
3597 
3598 	if (lun != SCAN_WILD_CARD && lun)
3599 		return -EINVAL;
3600 
3601 	if (!sata_pmp_attached(ap)) {
3602 		if (channel != SCAN_WILD_CARD && channel)
3603 			return -EINVAL;
3604 		devno = id;
3605 	} else {
3606 		if (id != SCAN_WILD_CARD && id)
3607 			return -EINVAL;
3608 		devno = channel;
3609 	}
3610 
3611 	spin_lock_irqsave(ap->lock, flags);
3612 
3613 	if (devno == SCAN_WILD_CARD) {
3614 		struct ata_link *link;
3615 
3616 		ata_for_each_link(link, ap, EDGE) {
3617 			struct ata_eh_info *ehi = &link->eh_info;
3618 			ehi->probe_mask |= ATA_ALL_DEVICES;
3619 			ehi->action |= ATA_EH_RESET;
3620 		}
3621 	} else {
3622 		struct ata_device *dev = ata_find_dev(ap, devno);
3623 
3624 		if (dev) {
3625 			struct ata_eh_info *ehi = &dev->link->eh_info;
3626 			ehi->probe_mask |= 1 << dev->devno;
3627 			ehi->action |= ATA_EH_RESET;
3628 		} else
3629 			rc = -EINVAL;
3630 	}
3631 
3632 	if (rc == 0) {
3633 		ata_port_schedule_eh(ap);
3634 		spin_unlock_irqrestore(ap->lock, flags);
3635 		ata_port_wait_eh(ap);
3636 	} else
3637 		spin_unlock_irqrestore(ap->lock, flags);
3638 
3639 	return rc;
3640 }
3641 
3642 /**
3643  *	ata_scsi_dev_rescan - initiate scsi_rescan_device()
3644  *	@work: Pointer to ATA port to perform scsi_rescan_device()
3645  *
3646  *	After ATA pass thru (SAT) commands are executed successfully,
3647  *	libata need to propagate the changes to SCSI layer.  This
3648  *	function must be executed from ata_aux_wq such that sdev
3649  *	attach/detach don't race with rescan.
3650  *
3651  *	LOCKING:
3652  *	Kernel thread context (may sleep).
3653  */
3654 void ata_scsi_dev_rescan(struct work_struct *work)
3655 {
3656 	struct ata_port *ap =
3657 		container_of(work, struct ata_port, scsi_rescan_task);
3658 	struct ata_link *link;
3659 	struct ata_device *dev;
3660 	unsigned long flags;
3661 
3662 	spin_lock_irqsave(ap->lock, flags);
3663 
3664 	ata_for_each_link(link, ap, EDGE) {
3665 		ata_for_each_dev(dev, link, ENABLED) {
3666 			struct scsi_device *sdev = dev->sdev;
3667 
3668 			if (!sdev)
3669 				continue;
3670 			if (scsi_device_get(sdev))
3671 				continue;
3672 
3673 			spin_unlock_irqrestore(ap->lock, flags);
3674 			scsi_rescan_device(&(sdev->sdev_gendev));
3675 			scsi_device_put(sdev);
3676 			spin_lock_irqsave(ap->lock, flags);
3677 		}
3678 	}
3679 
3680 	spin_unlock_irqrestore(ap->lock, flags);
3681 }
3682 
3683 /**
3684  *	ata_sas_port_alloc - Allocate port for a SAS attached SATA device
3685  *	@host: ATA host container for all SAS ports
3686  *	@port_info: Information from low-level host driver
3687  *	@shost: SCSI host that the scsi device is attached to
3688  *
3689  *	LOCKING:
3690  *	PCI/etc. bus probe sem.
3691  *
3692  *	RETURNS:
3693  *	ata_port pointer on success / NULL on failure.
3694  */
3695 
3696 struct ata_port *ata_sas_port_alloc(struct ata_host *host,
3697 				    struct ata_port_info *port_info,
3698 				    struct Scsi_Host *shost)
3699 {
3700 	struct ata_port *ap;
3701 
3702 	ap = ata_port_alloc(host);
3703 	if (!ap)
3704 		return NULL;
3705 
3706 	ap->port_no = 0;
3707 	ap->lock = shost->host_lock;
3708 	ap->pio_mask = port_info->pio_mask;
3709 	ap->mwdma_mask = port_info->mwdma_mask;
3710 	ap->udma_mask = port_info->udma_mask;
3711 	ap->flags |= port_info->flags;
3712 	ap->ops = port_info->port_ops;
3713 	ap->cbl = ATA_CBL_SATA;
3714 
3715 	return ap;
3716 }
3717 EXPORT_SYMBOL_GPL(ata_sas_port_alloc);
3718 
3719 /**
3720  *	ata_sas_port_start - Set port up for dma.
3721  *	@ap: Port to initialize
3722  *
3723  *	Called just after data structures for each port are
3724  *	initialized.
3725  *
3726  *	May be used as the port_start() entry in ata_port_operations.
3727  *
3728  *	LOCKING:
3729  *	Inherited from caller.
3730  */
3731 int ata_sas_port_start(struct ata_port *ap)
3732 {
3733 	return 0;
3734 }
3735 EXPORT_SYMBOL_GPL(ata_sas_port_start);
3736 
3737 /**
3738  *	ata_port_stop - Undo ata_sas_port_start()
3739  *	@ap: Port to shut down
3740  *
3741  *	May be used as the port_stop() entry in ata_port_operations.
3742  *
3743  *	LOCKING:
3744  *	Inherited from caller.
3745  */
3746 
3747 void ata_sas_port_stop(struct ata_port *ap)
3748 {
3749 }
3750 EXPORT_SYMBOL_GPL(ata_sas_port_stop);
3751 
3752 /**
3753  *	ata_sas_port_init - Initialize a SATA device
3754  *	@ap: SATA port to initialize
3755  *
3756  *	LOCKING:
3757  *	PCI/etc. bus probe sem.
3758  *
3759  *	RETURNS:
3760  *	Zero on success, non-zero on error.
3761  */
3762 
3763 int ata_sas_port_init(struct ata_port *ap)
3764 {
3765 	int rc = ap->ops->port_start(ap);
3766 
3767 	if (!rc) {
3768 		ap->print_id = ata_print_id++;
3769 		rc = ata_bus_probe(ap);
3770 	}
3771 
3772 	return rc;
3773 }
3774 EXPORT_SYMBOL_GPL(ata_sas_port_init);
3775 
3776 /**
3777  *	ata_sas_port_destroy - Destroy a SATA port allocated by ata_sas_port_alloc
3778  *	@ap: SATA port to destroy
3779  *
3780  */
3781 
3782 void ata_sas_port_destroy(struct ata_port *ap)
3783 {
3784 	if (ap->ops->port_stop)
3785 		ap->ops->port_stop(ap);
3786 	kfree(ap);
3787 }
3788 EXPORT_SYMBOL_GPL(ata_sas_port_destroy);
3789 
3790 /**
3791  *	ata_sas_slave_configure - Default slave_config routine for libata devices
3792  *	@sdev: SCSI device to configure
3793  *	@ap: ATA port to which SCSI device is attached
3794  *
3795  *	RETURNS:
3796  *	Zero.
3797  */
3798 
3799 int ata_sas_slave_configure(struct scsi_device *sdev, struct ata_port *ap)
3800 {
3801 	ata_scsi_sdev_config(sdev);
3802 	ata_scsi_dev_config(sdev, ap->link.device);
3803 	return 0;
3804 }
3805 EXPORT_SYMBOL_GPL(ata_sas_slave_configure);
3806 
3807 /**
3808  *	ata_sas_queuecmd - Issue SCSI cdb to libata-managed device
3809  *	@cmd: SCSI command to be sent
3810  *	@done: Completion function, called when command is complete
3811  *	@ap:	ATA port to which the command is being sent
3812  *
3813  *	RETURNS:
3814  *	Return value from __ata_scsi_queuecmd() if @cmd can be queued,
3815  *	0 otherwise.
3816  */
3817 
3818 int ata_sas_queuecmd(struct scsi_cmnd *cmd, void (*done)(struct scsi_cmnd *),
3819 		     struct ata_port *ap)
3820 {
3821 	int rc = 0;
3822 
3823 	ata_scsi_dump_cdb(ap, cmd);
3824 
3825 	if (likely(ata_dev_enabled(ap->link.device)))
3826 		rc = __ata_scsi_queuecmd(cmd, done, ap->link.device);
3827 	else {
3828 		cmd->result = (DID_BAD_TARGET << 16);
3829 		done(cmd);
3830 	}
3831 	return rc;
3832 }
3833 EXPORT_SYMBOL_GPL(ata_sas_queuecmd);
3834