xref: /linux/drivers/ata/libata-scsi.c (revision 492c826b9facefa84995f4dea917e301b5ee0884)
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 #include "libata-transport.h"
55 
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 
68 #define RW_RECOVERY_MPAGE 0x1
69 #define RW_RECOVERY_MPAGE_LEN 12
70 #define CACHE_MPAGE 0x8
71 #define CACHE_MPAGE_LEN 20
72 #define CONTROL_MPAGE 0xa
73 #define CONTROL_MPAGE_LEN 12
74 #define ALL_MPAGES 0x3f
75 #define ALL_SUB_MPAGES 0xff
76 
77 
78 static const u8 def_rw_recovery_mpage[RW_RECOVERY_MPAGE_LEN] = {
79 	RW_RECOVERY_MPAGE,
80 	RW_RECOVERY_MPAGE_LEN - 2,
81 	(1 << 7),	/* AWRE */
82 	0,		/* read retry count */
83 	0, 0, 0, 0,
84 	0,		/* write retry count */
85 	0, 0, 0
86 };
87 
88 static const u8 def_cache_mpage[CACHE_MPAGE_LEN] = {
89 	CACHE_MPAGE,
90 	CACHE_MPAGE_LEN - 2,
91 	0,		/* contains WCE, needs to be 0 for logic */
92 	0, 0, 0, 0, 0, 0, 0, 0, 0,
93 	0,		/* contains DRA, needs to be 0 for logic */
94 	0, 0, 0, 0, 0, 0, 0
95 };
96 
97 static const u8 def_control_mpage[CONTROL_MPAGE_LEN] = {
98 	CONTROL_MPAGE,
99 	CONTROL_MPAGE_LEN - 2,
100 	2,	/* DSENSE=0, GLTSD=1 */
101 	0,	/* [QAM+QERR may be 1, see 05-359r1] */
102 	0, 0, 0, 0, 0xff, 0xff,
103 	0, 30	/* extended self test time, see 05-359r1 */
104 };
105 
106 static const char *ata_lpm_policy_names[] = {
107 	[ATA_LPM_UNKNOWN]	= "max_performance",
108 	[ATA_LPM_MAX_POWER]	= "max_performance",
109 	[ATA_LPM_MED_POWER]	= "medium_power",
110 	[ATA_LPM_MIN_POWER]	= "min_power",
111 };
112 
113 static ssize_t ata_scsi_lpm_store(struct device *dev,
114 				  struct device_attribute *attr,
115 				  const char *buf, size_t count)
116 {
117 	struct Scsi_Host *shost = class_to_shost(dev);
118 	struct ata_port *ap = ata_shost_to_port(shost);
119 	enum ata_lpm_policy policy;
120 	unsigned long flags;
121 
122 	/* UNKNOWN is internal state, iterate from MAX_POWER */
123 	for (policy = ATA_LPM_MAX_POWER;
124 	     policy < ARRAY_SIZE(ata_lpm_policy_names); policy++) {
125 		const char *name = ata_lpm_policy_names[policy];
126 
127 		if (strncmp(name, buf, strlen(name)) == 0)
128 			break;
129 	}
130 	if (policy == ARRAY_SIZE(ata_lpm_policy_names))
131 		return -EINVAL;
132 
133 	spin_lock_irqsave(ap->lock, flags);
134 	ap->target_lpm_policy = policy;
135 	ata_port_schedule_eh(ap);
136 	spin_unlock_irqrestore(ap->lock, flags);
137 
138 	return count;
139 }
140 
141 static ssize_t ata_scsi_lpm_show(struct device *dev,
142 				 struct device_attribute *attr, char *buf)
143 {
144 	struct Scsi_Host *shost = class_to_shost(dev);
145 	struct ata_port *ap = ata_shost_to_port(shost);
146 
147 	if (ap->target_lpm_policy >= ARRAY_SIZE(ata_lpm_policy_names))
148 		return -EINVAL;
149 
150 	return snprintf(buf, PAGE_SIZE, "%s\n",
151 			ata_lpm_policy_names[ap->target_lpm_policy]);
152 }
153 DEVICE_ATTR(link_power_management_policy, S_IRUGO | S_IWUSR,
154 	    ata_scsi_lpm_show, ata_scsi_lpm_store);
155 EXPORT_SYMBOL_GPL(dev_attr_link_power_management_policy);
156 
157 static ssize_t ata_scsi_park_show(struct device *device,
158 				  struct device_attribute *attr, char *buf)
159 {
160 	struct scsi_device *sdev = to_scsi_device(device);
161 	struct ata_port *ap;
162 	struct ata_link *link;
163 	struct ata_device *dev;
164 	unsigned long flags, now;
165 	unsigned int uninitialized_var(msecs);
166 	int rc = 0;
167 
168 	ap = ata_shost_to_port(sdev->host);
169 
170 	spin_lock_irqsave(ap->lock, flags);
171 	dev = ata_scsi_find_dev(ap, sdev);
172 	if (!dev) {
173 		rc = -ENODEV;
174 		goto unlock;
175 	}
176 	if (dev->flags & ATA_DFLAG_NO_UNLOAD) {
177 		rc = -EOPNOTSUPP;
178 		goto unlock;
179 	}
180 
181 	link = dev->link;
182 	now = jiffies;
183 	if (ap->pflags & ATA_PFLAG_EH_IN_PROGRESS &&
184 	    link->eh_context.unloaded_mask & (1 << dev->devno) &&
185 	    time_after(dev->unpark_deadline, now))
186 		msecs = jiffies_to_msecs(dev->unpark_deadline - now);
187 	else
188 		msecs = 0;
189 
190 unlock:
191 	spin_unlock_irq(ap->lock);
192 
193 	return rc ? rc : snprintf(buf, 20, "%u\n", msecs);
194 }
195 
196 static ssize_t ata_scsi_park_store(struct device *device,
197 				   struct device_attribute *attr,
198 				   const char *buf, size_t len)
199 {
200 	struct scsi_device *sdev = to_scsi_device(device);
201 	struct ata_port *ap;
202 	struct ata_device *dev;
203 	long int input;
204 	unsigned long flags;
205 	int rc;
206 
207 	rc = strict_strtol(buf, 10, &input);
208 	if (rc || input < -2)
209 		return -EINVAL;
210 	if (input > ATA_TMOUT_MAX_PARK) {
211 		rc = -EOVERFLOW;
212 		input = ATA_TMOUT_MAX_PARK;
213 	}
214 
215 	ap = ata_shost_to_port(sdev->host);
216 
217 	spin_lock_irqsave(ap->lock, flags);
218 	dev = ata_scsi_find_dev(ap, sdev);
219 	if (unlikely(!dev)) {
220 		rc = -ENODEV;
221 		goto unlock;
222 	}
223 	if (dev->class != ATA_DEV_ATA) {
224 		rc = -EOPNOTSUPP;
225 		goto unlock;
226 	}
227 
228 	if (input >= 0) {
229 		if (dev->flags & ATA_DFLAG_NO_UNLOAD) {
230 			rc = -EOPNOTSUPP;
231 			goto unlock;
232 		}
233 
234 		dev->unpark_deadline = ata_deadline(jiffies, input);
235 		dev->link->eh_info.dev_action[dev->devno] |= ATA_EH_PARK;
236 		ata_port_schedule_eh(ap);
237 		complete(&ap->park_req_pending);
238 	} else {
239 		switch (input) {
240 		case -1:
241 			dev->flags &= ~ATA_DFLAG_NO_UNLOAD;
242 			break;
243 		case -2:
244 			dev->flags |= ATA_DFLAG_NO_UNLOAD;
245 			break;
246 		}
247 	}
248 unlock:
249 	spin_unlock_irqrestore(ap->lock, flags);
250 
251 	return rc ? rc : len;
252 }
253 DEVICE_ATTR(unload_heads, S_IRUGO | S_IWUSR,
254 	    ata_scsi_park_show, ata_scsi_park_store);
255 EXPORT_SYMBOL_GPL(dev_attr_unload_heads);
256 
257 static void ata_scsi_set_sense(struct scsi_cmnd *cmd, u8 sk, u8 asc, u8 ascq)
258 {
259 	cmd->result = (DRIVER_SENSE << 24) | SAM_STAT_CHECK_CONDITION;
260 
261 	scsi_build_sense_buffer(0, cmd->sense_buffer, sk, asc, ascq);
262 }
263 
264 static ssize_t
265 ata_scsi_em_message_store(struct device *dev, struct device_attribute *attr,
266 			  const char *buf, size_t count)
267 {
268 	struct Scsi_Host *shost = class_to_shost(dev);
269 	struct ata_port *ap = ata_shost_to_port(shost);
270 	if (ap->ops->em_store && (ap->flags & ATA_FLAG_EM))
271 		return ap->ops->em_store(ap, buf, count);
272 	return -EINVAL;
273 }
274 
275 static ssize_t
276 ata_scsi_em_message_show(struct device *dev, struct device_attribute *attr,
277 			 char *buf)
278 {
279 	struct Scsi_Host *shost = class_to_shost(dev);
280 	struct ata_port *ap = ata_shost_to_port(shost);
281 
282 	if (ap->ops->em_show && (ap->flags & ATA_FLAG_EM))
283 		return ap->ops->em_show(ap, buf);
284 	return -EINVAL;
285 }
286 DEVICE_ATTR(em_message, S_IRUGO | S_IWUSR,
287 		ata_scsi_em_message_show, ata_scsi_em_message_store);
288 EXPORT_SYMBOL_GPL(dev_attr_em_message);
289 
290 static ssize_t
291 ata_scsi_em_message_type_show(struct device *dev, struct device_attribute *attr,
292 			      char *buf)
293 {
294 	struct Scsi_Host *shost = class_to_shost(dev);
295 	struct ata_port *ap = ata_shost_to_port(shost);
296 
297 	return snprintf(buf, 23, "%d\n", ap->em_message_type);
298 }
299 DEVICE_ATTR(em_message_type, S_IRUGO,
300 		  ata_scsi_em_message_type_show, NULL);
301 EXPORT_SYMBOL_GPL(dev_attr_em_message_type);
302 
303 static ssize_t
304 ata_scsi_activity_show(struct device *dev, struct device_attribute *attr,
305 		char *buf)
306 {
307 	struct scsi_device *sdev = to_scsi_device(dev);
308 	struct ata_port *ap = ata_shost_to_port(sdev->host);
309 	struct ata_device *atadev = ata_scsi_find_dev(ap, sdev);
310 
311 	if (ap->ops->sw_activity_show && (ap->flags & ATA_FLAG_SW_ACTIVITY))
312 		return ap->ops->sw_activity_show(atadev, buf);
313 	return -EINVAL;
314 }
315 
316 static ssize_t
317 ata_scsi_activity_store(struct device *dev, struct device_attribute *attr,
318 	const char *buf, size_t count)
319 {
320 	struct scsi_device *sdev = to_scsi_device(dev);
321 	struct ata_port *ap = ata_shost_to_port(sdev->host);
322 	struct ata_device *atadev = ata_scsi_find_dev(ap, sdev);
323 	enum sw_activity val;
324 	int rc;
325 
326 	if (ap->ops->sw_activity_store && (ap->flags & ATA_FLAG_SW_ACTIVITY)) {
327 		val = simple_strtoul(buf, NULL, 0);
328 		switch (val) {
329 		case OFF: case BLINK_ON: case BLINK_OFF:
330 			rc = ap->ops->sw_activity_store(atadev, val);
331 			if (!rc)
332 				return count;
333 			else
334 				return rc;
335 		}
336 	}
337 	return -EINVAL;
338 }
339 DEVICE_ATTR(sw_activity, S_IWUSR | S_IRUGO, ata_scsi_activity_show,
340 			ata_scsi_activity_store);
341 EXPORT_SYMBOL_GPL(dev_attr_sw_activity);
342 
343 struct device_attribute *ata_common_sdev_attrs[] = {
344 	&dev_attr_unload_heads,
345 	NULL
346 };
347 EXPORT_SYMBOL_GPL(ata_common_sdev_attrs);
348 
349 static void ata_scsi_invalid_field(struct scsi_cmnd *cmd)
350 {
351 	ata_scsi_set_sense(cmd, ILLEGAL_REQUEST, 0x24, 0x0);
352 	/* "Invalid field in cbd" */
353 	cmd->scsi_done(cmd);
354 }
355 
356 /**
357  *	ata_std_bios_param - generic bios head/sector/cylinder calculator used by sd.
358  *	@sdev: SCSI device for which BIOS geometry is to be determined
359  *	@bdev: block device associated with @sdev
360  *	@capacity: capacity of SCSI device
361  *	@geom: location to which geometry will be output
362  *
363  *	Generic bios head/sector/cylinder calculator
364  *	used by sd. Most BIOSes nowadays expect a XXX/255/16  (CHS)
365  *	mapping. Some situations may arise where the disk is not
366  *	bootable if this is not used.
367  *
368  *	LOCKING:
369  *	Defined by the SCSI layer.  We don't really care.
370  *
371  *	RETURNS:
372  *	Zero.
373  */
374 int ata_std_bios_param(struct scsi_device *sdev, struct block_device *bdev,
375 		       sector_t capacity, int geom[])
376 {
377 	geom[0] = 255;
378 	geom[1] = 63;
379 	sector_div(capacity, 255*63);
380 	geom[2] = capacity;
381 
382 	return 0;
383 }
384 
385 /**
386  *	ata_scsi_unlock_native_capacity - unlock native capacity
387  *	@sdev: SCSI device to adjust device capacity for
388  *
389  *	This function is called if a partition on @sdev extends beyond
390  *	the end of the device.  It requests EH to unlock HPA.
391  *
392  *	LOCKING:
393  *	Defined by the SCSI layer.  Might sleep.
394  */
395 void ata_scsi_unlock_native_capacity(struct scsi_device *sdev)
396 {
397 	struct ata_port *ap = ata_shost_to_port(sdev->host);
398 	struct ata_device *dev;
399 	unsigned long flags;
400 
401 	spin_lock_irqsave(ap->lock, flags);
402 
403 	dev = ata_scsi_find_dev(ap, sdev);
404 	if (dev && dev->n_sectors < dev->n_native_sectors) {
405 		dev->flags |= ATA_DFLAG_UNLOCK_HPA;
406 		dev->link->eh_info.action |= ATA_EH_RESET;
407 		ata_port_schedule_eh(ap);
408 	}
409 
410 	spin_unlock_irqrestore(ap->lock, flags);
411 	ata_port_wait_eh(ap);
412 }
413 
414 /**
415  *	ata_get_identity - Handler for HDIO_GET_IDENTITY ioctl
416  *	@ap: target port
417  *	@sdev: SCSI device to get identify data for
418  *	@arg: User buffer area for identify data
419  *
420  *	LOCKING:
421  *	Defined by the SCSI layer.  We don't really care.
422  *
423  *	RETURNS:
424  *	Zero on success, negative errno on error.
425  */
426 static int ata_get_identity(struct ata_port *ap, struct scsi_device *sdev,
427 			    void __user *arg)
428 {
429 	struct ata_device *dev = ata_scsi_find_dev(ap, sdev);
430 	u16 __user *dst = arg;
431 	char buf[40];
432 
433 	if (!dev)
434 		return -ENOMSG;
435 
436 	if (copy_to_user(dst, dev->id, ATA_ID_WORDS * sizeof(u16)))
437 		return -EFAULT;
438 
439 	ata_id_string(dev->id, buf, ATA_ID_PROD, ATA_ID_PROD_LEN);
440 	if (copy_to_user(dst + ATA_ID_PROD, buf, ATA_ID_PROD_LEN))
441 		return -EFAULT;
442 
443 	ata_id_string(dev->id, buf, ATA_ID_FW_REV, ATA_ID_FW_REV_LEN);
444 	if (copy_to_user(dst + ATA_ID_FW_REV, buf, ATA_ID_FW_REV_LEN))
445 		return -EFAULT;
446 
447 	ata_id_string(dev->id, buf, ATA_ID_SERNO, ATA_ID_SERNO_LEN);
448 	if (copy_to_user(dst + ATA_ID_SERNO, buf, ATA_ID_SERNO_LEN))
449 		return -EFAULT;
450 
451 	return 0;
452 }
453 
454 /**
455  *	ata_cmd_ioctl - Handler for HDIO_DRIVE_CMD ioctl
456  *	@scsidev: Device to which we are issuing command
457  *	@arg: User provided data for issuing command
458  *
459  *	LOCKING:
460  *	Defined by the SCSI layer.  We don't really care.
461  *
462  *	RETURNS:
463  *	Zero on success, negative errno on error.
464  */
465 int ata_cmd_ioctl(struct scsi_device *scsidev, void __user *arg)
466 {
467 	int rc = 0;
468 	u8 scsi_cmd[MAX_COMMAND_SIZE];
469 	u8 args[4], *argbuf = NULL, *sensebuf = NULL;
470 	int argsize = 0;
471 	enum dma_data_direction data_dir;
472 	int cmd_result;
473 
474 	if (arg == NULL)
475 		return -EINVAL;
476 
477 	if (copy_from_user(args, arg, sizeof(args)))
478 		return -EFAULT;
479 
480 	sensebuf = kzalloc(SCSI_SENSE_BUFFERSIZE, GFP_NOIO);
481 	if (!sensebuf)
482 		return -ENOMEM;
483 
484 	memset(scsi_cmd, 0, sizeof(scsi_cmd));
485 
486 	if (args[3]) {
487 		argsize = ATA_SECT_SIZE * args[3];
488 		argbuf = kmalloc(argsize, GFP_KERNEL);
489 		if (argbuf == NULL) {
490 			rc = -ENOMEM;
491 			goto error;
492 		}
493 
494 		scsi_cmd[1]  = (4 << 1); /* PIO Data-in */
495 		scsi_cmd[2]  = 0x0e;     /* no off.line or cc, read from dev,
496 					    block count in sector count field */
497 		data_dir = DMA_FROM_DEVICE;
498 	} else {
499 		scsi_cmd[1]  = (3 << 1); /* Non-data */
500 		scsi_cmd[2]  = 0x20;     /* cc but no off.line or data xfer */
501 		data_dir = DMA_NONE;
502 	}
503 
504 	scsi_cmd[0] = ATA_16;
505 
506 	scsi_cmd[4] = args[2];
507 	if (args[0] == ATA_CMD_SMART) { /* hack -- ide driver does this too */
508 		scsi_cmd[6]  = args[3];
509 		scsi_cmd[8]  = args[1];
510 		scsi_cmd[10] = 0x4f;
511 		scsi_cmd[12] = 0xc2;
512 	} else {
513 		scsi_cmd[6]  = args[1];
514 	}
515 	scsi_cmd[14] = args[0];
516 
517 	/* Good values for timeout and retries?  Values below
518 	   from scsi_ioctl_send_command() for default case... */
519 	cmd_result = scsi_execute(scsidev, scsi_cmd, data_dir, argbuf, argsize,
520 				  sensebuf, (10*HZ), 5, 0, NULL);
521 
522 	if (driver_byte(cmd_result) == DRIVER_SENSE) {/* sense data available */
523 		u8 *desc = sensebuf + 8;
524 		cmd_result &= ~(0xFF<<24); /* DRIVER_SENSE is not an error */
525 
526 		/* If we set cc then ATA pass-through will cause a
527 		 * check condition even if no error. Filter that. */
528 		if (cmd_result & SAM_STAT_CHECK_CONDITION) {
529 			struct scsi_sense_hdr sshdr;
530 			scsi_normalize_sense(sensebuf, SCSI_SENSE_BUFFERSIZE,
531 					     &sshdr);
532 			if (sshdr.sense_key == 0 &&
533 			    sshdr.asc == 0 && sshdr.ascq == 0)
534 				cmd_result &= ~SAM_STAT_CHECK_CONDITION;
535 		}
536 
537 		/* Send userspace a few ATA registers (same as drivers/ide) */
538 		if (sensebuf[0] == 0x72 &&	/* format is "descriptor" */
539 		    desc[0] == 0x09) {		/* code is "ATA Descriptor" */
540 			args[0] = desc[13];	/* status */
541 			args[1] = desc[3];	/* error */
542 			args[2] = desc[5];	/* sector count (0:7) */
543 			if (copy_to_user(arg, args, sizeof(args)))
544 				rc = -EFAULT;
545 		}
546 	}
547 
548 
549 	if (cmd_result) {
550 		rc = -EIO;
551 		goto error;
552 	}
553 
554 	if ((argbuf)
555 	 && copy_to_user(arg + sizeof(args), argbuf, argsize))
556 		rc = -EFAULT;
557 error:
558 	kfree(sensebuf);
559 	kfree(argbuf);
560 	return rc;
561 }
562 
563 /**
564  *	ata_task_ioctl - Handler for HDIO_DRIVE_TASK ioctl
565  *	@scsidev: Device to which we are issuing command
566  *	@arg: User provided data for issuing command
567  *
568  *	LOCKING:
569  *	Defined by the SCSI layer.  We don't really care.
570  *
571  *	RETURNS:
572  *	Zero on success, negative errno on error.
573  */
574 int ata_task_ioctl(struct scsi_device *scsidev, void __user *arg)
575 {
576 	int rc = 0;
577 	u8 scsi_cmd[MAX_COMMAND_SIZE];
578 	u8 args[7], *sensebuf = NULL;
579 	int cmd_result;
580 
581 	if (arg == NULL)
582 		return -EINVAL;
583 
584 	if (copy_from_user(args, arg, sizeof(args)))
585 		return -EFAULT;
586 
587 	sensebuf = kzalloc(SCSI_SENSE_BUFFERSIZE, GFP_NOIO);
588 	if (!sensebuf)
589 		return -ENOMEM;
590 
591 	memset(scsi_cmd, 0, sizeof(scsi_cmd));
592 	scsi_cmd[0]  = ATA_16;
593 	scsi_cmd[1]  = (3 << 1); /* Non-data */
594 	scsi_cmd[2]  = 0x20;     /* cc but no off.line or data xfer */
595 	scsi_cmd[4]  = args[1];
596 	scsi_cmd[6]  = args[2];
597 	scsi_cmd[8]  = args[3];
598 	scsi_cmd[10] = args[4];
599 	scsi_cmd[12] = args[5];
600 	scsi_cmd[13] = args[6] & 0x4f;
601 	scsi_cmd[14] = args[0];
602 
603 	/* Good values for timeout and retries?  Values below
604 	   from scsi_ioctl_send_command() for default case... */
605 	cmd_result = scsi_execute(scsidev, scsi_cmd, DMA_NONE, NULL, 0,
606 				sensebuf, (10*HZ), 5, 0, NULL);
607 
608 	if (driver_byte(cmd_result) == DRIVER_SENSE) {/* sense data available */
609 		u8 *desc = sensebuf + 8;
610 		cmd_result &= ~(0xFF<<24); /* DRIVER_SENSE is not an error */
611 
612 		/* If we set cc then ATA pass-through will cause a
613 		 * check condition even if no error. Filter that. */
614 		if (cmd_result & SAM_STAT_CHECK_CONDITION) {
615 			struct scsi_sense_hdr sshdr;
616 			scsi_normalize_sense(sensebuf, SCSI_SENSE_BUFFERSIZE,
617 						&sshdr);
618 			if (sshdr.sense_key == 0 &&
619 				sshdr.asc == 0 && sshdr.ascq == 0)
620 				cmd_result &= ~SAM_STAT_CHECK_CONDITION;
621 		}
622 
623 		/* Send userspace ATA registers */
624 		if (sensebuf[0] == 0x72 &&	/* format is "descriptor" */
625 				desc[0] == 0x09) {/* code is "ATA Descriptor" */
626 			args[0] = desc[13];	/* status */
627 			args[1] = desc[3];	/* error */
628 			args[2] = desc[5];	/* sector count (0:7) */
629 			args[3] = desc[7];	/* lbal */
630 			args[4] = desc[9];	/* lbam */
631 			args[5] = desc[11];	/* lbah */
632 			args[6] = desc[12];	/* select */
633 			if (copy_to_user(arg, args, sizeof(args)))
634 				rc = -EFAULT;
635 		}
636 	}
637 
638 	if (cmd_result) {
639 		rc = -EIO;
640 		goto error;
641 	}
642 
643  error:
644 	kfree(sensebuf);
645 	return rc;
646 }
647 
648 static int ata_ioc32(struct ata_port *ap)
649 {
650 	if (ap->flags & ATA_FLAG_PIO_DMA)
651 		return 1;
652 	if (ap->pflags & ATA_PFLAG_PIO32)
653 		return 1;
654 	return 0;
655 }
656 
657 int ata_sas_scsi_ioctl(struct ata_port *ap, struct scsi_device *scsidev,
658 		     int cmd, void __user *arg)
659 {
660 	int val = -EINVAL, rc = -EINVAL;
661 	unsigned long flags;
662 
663 	switch (cmd) {
664 	case ATA_IOC_GET_IO32:
665 		spin_lock_irqsave(ap->lock, flags);
666 		val = ata_ioc32(ap);
667 		spin_unlock_irqrestore(ap->lock, flags);
668 		if (copy_to_user(arg, &val, 1))
669 			return -EFAULT;
670 		return 0;
671 
672 	case ATA_IOC_SET_IO32:
673 		val = (unsigned long) arg;
674 		rc = 0;
675 		spin_lock_irqsave(ap->lock, flags);
676 		if (ap->pflags & ATA_PFLAG_PIO32CHANGE) {
677 			if (val)
678 				ap->pflags |= ATA_PFLAG_PIO32;
679 			else
680 				ap->pflags &= ~ATA_PFLAG_PIO32;
681 		} else {
682 			if (val != ata_ioc32(ap))
683 				rc = -EINVAL;
684 		}
685 		spin_unlock_irqrestore(ap->lock, flags);
686 		return rc;
687 
688 	case HDIO_GET_IDENTITY:
689 		return ata_get_identity(ap, scsidev, arg);
690 
691 	case HDIO_DRIVE_CMD:
692 		if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
693 			return -EACCES;
694 		return ata_cmd_ioctl(scsidev, arg);
695 
696 	case HDIO_DRIVE_TASK:
697 		if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
698 			return -EACCES;
699 		return ata_task_ioctl(scsidev, arg);
700 
701 	default:
702 		rc = -ENOTTY;
703 		break;
704 	}
705 
706 	return rc;
707 }
708 EXPORT_SYMBOL_GPL(ata_sas_scsi_ioctl);
709 
710 int ata_scsi_ioctl(struct scsi_device *scsidev, int cmd, void __user *arg)
711 {
712 	return ata_sas_scsi_ioctl(ata_shost_to_port(scsidev->host),
713 				scsidev, cmd, arg);
714 }
715 EXPORT_SYMBOL_GPL(ata_scsi_ioctl);
716 
717 /**
718  *	ata_scsi_qc_new - acquire new ata_queued_cmd reference
719  *	@dev: ATA device to which the new command is attached
720  *	@cmd: SCSI command that originated this ATA command
721  *
722  *	Obtain a reference to an unused ata_queued_cmd structure,
723  *	which is the basic libata structure representing a single
724  *	ATA command sent to the hardware.
725  *
726  *	If a command was available, fill in the SCSI-specific
727  *	portions of the structure with information on the
728  *	current command.
729  *
730  *	LOCKING:
731  *	spin_lock_irqsave(host lock)
732  *
733  *	RETURNS:
734  *	Command allocated, or %NULL if none available.
735  */
736 static struct ata_queued_cmd *ata_scsi_qc_new(struct ata_device *dev,
737 					      struct scsi_cmnd *cmd)
738 {
739 	struct ata_queued_cmd *qc;
740 
741 	qc = ata_qc_new_init(dev);
742 	if (qc) {
743 		qc->scsicmd = cmd;
744 		qc->scsidone = cmd->scsi_done;
745 
746 		qc->sg = scsi_sglist(cmd);
747 		qc->n_elem = scsi_sg_count(cmd);
748 	} else {
749 		cmd->result = (DID_OK << 16) | (QUEUE_FULL << 1);
750 		cmd->scsi_done(cmd);
751 	}
752 
753 	return qc;
754 }
755 
756 static void ata_qc_set_pc_nbytes(struct ata_queued_cmd *qc)
757 {
758 	struct scsi_cmnd *scmd = qc->scsicmd;
759 
760 	qc->extrabytes = scmd->request->extra_len;
761 	qc->nbytes = scsi_bufflen(scmd) + qc->extrabytes;
762 }
763 
764 /**
765  *	ata_dump_status - user friendly display of error info
766  *	@id: id of the port in question
767  *	@tf: ptr to filled out taskfile
768  *
769  *	Decode and dump the ATA error/status registers for the user so
770  *	that they have some idea what really happened at the non
771  *	make-believe layer.
772  *
773  *	LOCKING:
774  *	inherited from caller
775  */
776 static void ata_dump_status(unsigned id, struct ata_taskfile *tf)
777 {
778 	u8 stat = tf->command, err = tf->feature;
779 
780 	printk(KERN_WARNING "ata%u: status=0x%02x { ", id, stat);
781 	if (stat & ATA_BUSY) {
782 		printk("Busy }\n");	/* Data is not valid in this case */
783 	} else {
784 		if (stat & 0x40)	printk("DriveReady ");
785 		if (stat & 0x20)	printk("DeviceFault ");
786 		if (stat & 0x10)	printk("SeekComplete ");
787 		if (stat & 0x08)	printk("DataRequest ");
788 		if (stat & 0x04)	printk("CorrectedError ");
789 		if (stat & 0x02)	printk("Index ");
790 		if (stat & 0x01)	printk("Error ");
791 		printk("}\n");
792 
793 		if (err) {
794 			printk(KERN_WARNING "ata%u: error=0x%02x { ", id, err);
795 			if (err & 0x04)		printk("DriveStatusError ");
796 			if (err & 0x80) {
797 				if (err & 0x04)	printk("BadCRC ");
798 				else		printk("Sector ");
799 			}
800 			if (err & 0x40)		printk("UncorrectableError ");
801 			if (err & 0x10)		printk("SectorIdNotFound ");
802 			if (err & 0x02)		printk("TrackZeroNotFound ");
803 			if (err & 0x01)		printk("AddrMarkNotFound ");
804 			printk("}\n");
805 		}
806 	}
807 }
808 
809 /**
810  *	ata_to_sense_error - convert ATA error to SCSI error
811  *	@id: ATA device number
812  *	@drv_stat: value contained in ATA status register
813  *	@drv_err: value contained in ATA error register
814  *	@sk: the sense key we'll fill out
815  *	@asc: the additional sense code we'll fill out
816  *	@ascq: the additional sense code qualifier we'll fill out
817  *	@verbose: be verbose
818  *
819  *	Converts an ATA error into a SCSI error.  Fill out pointers to
820  *	SK, ASC, and ASCQ bytes for later use in fixed or descriptor
821  *	format sense blocks.
822  *
823  *	LOCKING:
824  *	spin_lock_irqsave(host lock)
825  */
826 static void ata_to_sense_error(unsigned id, u8 drv_stat, u8 drv_err, u8 *sk,
827 			       u8 *asc, u8 *ascq, int verbose)
828 {
829 	int i;
830 
831 	/* Based on the 3ware driver translation table */
832 	static const unsigned char sense_table[][4] = {
833 		/* BBD|ECC|ID|MAR */
834 		{0xd1, 		ABORTED_COMMAND, 0x00, 0x00}, 	// Device busy                  Aborted command
835 		/* BBD|ECC|ID */
836 		{0xd0,  	ABORTED_COMMAND, 0x00, 0x00}, 	// Device busy                  Aborted command
837 		/* ECC|MC|MARK */
838 		{0x61, 		HARDWARE_ERROR, 0x00, 0x00}, 	// Device fault                 Hardware error
839 		/* ICRC|ABRT */		/* NB: ICRC & !ABRT is BBD */
840 		{0x84, 		ABORTED_COMMAND, 0x47, 0x00}, 	// Data CRC error               SCSI parity error
841 		/* MC|ID|ABRT|TRK0|MARK */
842 		{0x37, 		NOT_READY, 0x04, 0x00}, 	// Unit offline                 Not ready
843 		/* MCR|MARK */
844 		{0x09, 		NOT_READY, 0x04, 0x00}, 	// Unrecovered disk error       Not ready
845 		/*  Bad address mark */
846 		{0x01, 		MEDIUM_ERROR, 0x13, 0x00}, 	// Address mark not found       Address mark not found for data field
847 		/* TRK0 */
848 		{0x02, 		HARDWARE_ERROR, 0x00, 0x00}, 	// Track 0 not found		  Hardware error
849 		/* Abort & !ICRC */
850 		{0x04, 		ABORTED_COMMAND, 0x00, 0x00}, 	// Aborted command              Aborted command
851 		/* Media change request */
852 		{0x08, 		NOT_READY, 0x04, 0x00}, 	// Media change request	  FIXME: faking offline
853 		/* SRV */
854 		{0x10, 		ABORTED_COMMAND, 0x14, 0x00}, 	// ID not found                 Recorded entity not found
855 		/* Media change */
856 		{0x08,  	NOT_READY, 0x04, 0x00}, 	// Media change		  FIXME: faking offline
857 		/* ECC */
858 		{0x40, 		MEDIUM_ERROR, 0x11, 0x04}, 	// Uncorrectable ECC error      Unrecovered read error
859 		/* BBD - block marked bad */
860 		{0x80, 		MEDIUM_ERROR, 0x11, 0x04}, 	// Block marked bad		  Medium error, unrecovered read error
861 		{0xFF, 0xFF, 0xFF, 0xFF}, // END mark
862 	};
863 	static const unsigned char stat_table[][4] = {
864 		/* Must be first because BUSY means no other bits valid */
865 		{0x80, 		ABORTED_COMMAND, 0x47, 0x00},	// Busy, fake parity for now
866 		{0x20, 		HARDWARE_ERROR,  0x00, 0x00}, 	// Device fault
867 		{0x08, 		ABORTED_COMMAND, 0x47, 0x00},	// Timed out in xfer, fake parity for now
868 		{0x04, 		RECOVERED_ERROR, 0x11, 0x00},	// Recovered ECC error	  Medium error, recovered
869 		{0xFF, 0xFF, 0xFF, 0xFF}, // END mark
870 	};
871 
872 	/*
873 	 *	Is this an error we can process/parse
874 	 */
875 	if (drv_stat & ATA_BUSY) {
876 		drv_err = 0;	/* Ignore the err bits, they're invalid */
877 	}
878 
879 	if (drv_err) {
880 		/* Look for drv_err */
881 		for (i = 0; sense_table[i][0] != 0xFF; i++) {
882 			/* Look for best matches first */
883 			if ((sense_table[i][0] & drv_err) ==
884 			    sense_table[i][0]) {
885 				*sk = sense_table[i][1];
886 				*asc = sense_table[i][2];
887 				*ascq = sense_table[i][3];
888 				goto translate_done;
889 			}
890 		}
891 		/* No immediate match */
892 		if (verbose)
893 			printk(KERN_WARNING "ata%u: no sense translation for "
894 			       "error 0x%02x\n", id, drv_err);
895 	}
896 
897 	/* Fall back to interpreting status bits */
898 	for (i = 0; stat_table[i][0] != 0xFF; i++) {
899 		if (stat_table[i][0] & drv_stat) {
900 			*sk = stat_table[i][1];
901 			*asc = stat_table[i][2];
902 			*ascq = stat_table[i][3];
903 			goto translate_done;
904 		}
905 	}
906 	/* No error?  Undecoded? */
907 	if (verbose)
908 		printk(KERN_WARNING "ata%u: no sense translation for "
909 		       "status: 0x%02x\n", id, drv_stat);
910 
911 	/* We need a sensible error return here, which is tricky, and one
912 	   that won't cause people to do things like return a disk wrongly */
913 	*sk = ABORTED_COMMAND;
914 	*asc = 0x00;
915 	*ascq = 0x00;
916 
917  translate_done:
918 	if (verbose)
919 		printk(KERN_ERR "ata%u: translated ATA stat/err 0x%02x/%02x "
920 		       "to SCSI SK/ASC/ASCQ 0x%x/%02x/%02x\n",
921 		       id, drv_stat, drv_err, *sk, *asc, *ascq);
922 	return;
923 }
924 
925 /*
926  *	ata_gen_passthru_sense - Generate check condition sense block.
927  *	@qc: Command that completed.
928  *
929  *	This function is specific to the ATA descriptor format sense
930  *	block specified for the ATA pass through commands.  Regardless
931  *	of whether the command errored or not, return a sense
932  *	block. Copy all controller registers into the sense
933  *	block. Clear sense key, ASC & ASCQ if there is no error.
934  *
935  *	LOCKING:
936  *	None.
937  */
938 static void ata_gen_passthru_sense(struct ata_queued_cmd *qc)
939 {
940 	struct scsi_cmnd *cmd = qc->scsicmd;
941 	struct ata_taskfile *tf = &qc->result_tf;
942 	unsigned char *sb = cmd->sense_buffer;
943 	unsigned char *desc = sb + 8;
944 	int verbose = qc->ap->ops->error_handler == NULL;
945 
946 	memset(sb, 0, SCSI_SENSE_BUFFERSIZE);
947 
948 	cmd->result = (DRIVER_SENSE << 24) | SAM_STAT_CHECK_CONDITION;
949 
950 	/*
951 	 * Use ata_to_sense_error() to map status register bits
952 	 * onto sense key, asc & ascq.
953 	 */
954 	if (qc->err_mask ||
955 	    tf->command & (ATA_BUSY | ATA_DF | ATA_ERR | ATA_DRQ)) {
956 		ata_to_sense_error(qc->ap->print_id, tf->command, tf->feature,
957 				   &sb[1], &sb[2], &sb[3], verbose);
958 		sb[1] &= 0x0f;
959 	}
960 
961 	/*
962 	 * Sense data is current and format is descriptor.
963 	 */
964 	sb[0] = 0x72;
965 
966 	desc[0] = 0x09;
967 
968 	/* set length of additional sense data */
969 	sb[7] = 14;
970 	desc[1] = 12;
971 
972 	/*
973 	 * Copy registers into sense buffer.
974 	 */
975 	desc[2] = 0x00;
976 	desc[3] = tf->feature;	/* == error reg */
977 	desc[5] = tf->nsect;
978 	desc[7] = tf->lbal;
979 	desc[9] = tf->lbam;
980 	desc[11] = tf->lbah;
981 	desc[12] = tf->device;
982 	desc[13] = tf->command; /* == status reg */
983 
984 	/*
985 	 * Fill in Extend bit, and the high order bytes
986 	 * if applicable.
987 	 */
988 	if (tf->flags & ATA_TFLAG_LBA48) {
989 		desc[2] |= 0x01;
990 		desc[4] = tf->hob_nsect;
991 		desc[6] = tf->hob_lbal;
992 		desc[8] = tf->hob_lbam;
993 		desc[10] = tf->hob_lbah;
994 	}
995 }
996 
997 /**
998  *	ata_gen_ata_sense - generate a SCSI fixed sense block
999  *	@qc: Command that we are erroring out
1000  *
1001  *	Generate sense block for a failed ATA command @qc.  Descriptor
1002  *	format is used to accommodate LBA48 block address.
1003  *
1004  *	LOCKING:
1005  *	None.
1006  */
1007 static void ata_gen_ata_sense(struct ata_queued_cmd *qc)
1008 {
1009 	struct ata_device *dev = qc->dev;
1010 	struct scsi_cmnd *cmd = qc->scsicmd;
1011 	struct ata_taskfile *tf = &qc->result_tf;
1012 	unsigned char *sb = cmd->sense_buffer;
1013 	unsigned char *desc = sb + 8;
1014 	int verbose = qc->ap->ops->error_handler == NULL;
1015 	u64 block;
1016 
1017 	memset(sb, 0, SCSI_SENSE_BUFFERSIZE);
1018 
1019 	cmd->result = (DRIVER_SENSE << 24) | SAM_STAT_CHECK_CONDITION;
1020 
1021 	/* sense data is current and format is descriptor */
1022 	sb[0] = 0x72;
1023 
1024 	/* Use ata_to_sense_error() to map status register bits
1025 	 * onto sense key, asc & ascq.
1026 	 */
1027 	if (qc->err_mask ||
1028 	    tf->command & (ATA_BUSY | ATA_DF | ATA_ERR | ATA_DRQ)) {
1029 		ata_to_sense_error(qc->ap->print_id, tf->command, tf->feature,
1030 				   &sb[1], &sb[2], &sb[3], verbose);
1031 		sb[1] &= 0x0f;
1032 	}
1033 
1034 	block = ata_tf_read_block(&qc->result_tf, dev);
1035 
1036 	/* information sense data descriptor */
1037 	sb[7] = 12;
1038 	desc[0] = 0x00;
1039 	desc[1] = 10;
1040 
1041 	desc[2] |= 0x80;	/* valid */
1042 	desc[6] = block >> 40;
1043 	desc[7] = block >> 32;
1044 	desc[8] = block >> 24;
1045 	desc[9] = block >> 16;
1046 	desc[10] = block >> 8;
1047 	desc[11] = block;
1048 }
1049 
1050 static void ata_scsi_sdev_config(struct scsi_device *sdev)
1051 {
1052 	sdev->use_10_for_rw = 1;
1053 	sdev->use_10_for_ms = 1;
1054 
1055 	/* Schedule policy is determined by ->qc_defer() callback and
1056 	 * it needs to see every deferred qc.  Set dev_blocked to 1 to
1057 	 * prevent SCSI midlayer from automatically deferring
1058 	 * requests.
1059 	 */
1060 	sdev->max_device_blocked = 1;
1061 }
1062 
1063 /**
1064  *	atapi_drain_needed - Check whether data transfer may overflow
1065  *	@rq: request to be checked
1066  *
1067  *	ATAPI commands which transfer variable length data to host
1068  *	might overflow due to application error or hardare bug.  This
1069  *	function checks whether overflow should be drained and ignored
1070  *	for @request.
1071  *
1072  *	LOCKING:
1073  *	None.
1074  *
1075  *	RETURNS:
1076  *	1 if ; otherwise, 0.
1077  */
1078 static int atapi_drain_needed(struct request *rq)
1079 {
1080 	if (likely(rq->cmd_type != REQ_TYPE_BLOCK_PC))
1081 		return 0;
1082 
1083 	if (!blk_rq_bytes(rq) || (rq->cmd_flags & REQ_WRITE))
1084 		return 0;
1085 
1086 	return atapi_cmd_type(rq->cmd[0]) == ATAPI_MISC;
1087 }
1088 
1089 static int ata_scsi_dev_config(struct scsi_device *sdev,
1090 			       struct ata_device *dev)
1091 {
1092 	struct request_queue *q = sdev->request_queue;
1093 
1094 	if (!ata_id_has_unload(dev->id))
1095 		dev->flags |= ATA_DFLAG_NO_UNLOAD;
1096 
1097 	/* configure max sectors */
1098 	blk_queue_max_hw_sectors(q, dev->max_sectors);
1099 
1100 	if (dev->class == ATA_DEV_ATAPI) {
1101 		void *buf;
1102 
1103 		sdev->sector_size = ATA_SECT_SIZE;
1104 
1105 		/* set DMA padding */
1106 		blk_queue_update_dma_pad(q, ATA_DMA_PAD_SZ - 1);
1107 
1108 		/* configure draining */
1109 		buf = kmalloc(ATAPI_MAX_DRAIN, q->bounce_gfp | GFP_KERNEL);
1110 		if (!buf) {
1111 			ata_dev_printk(dev, KERN_ERR,
1112 				       "drain buffer allocation failed\n");
1113 			return -ENOMEM;
1114 		}
1115 
1116 		blk_queue_dma_drain(q, atapi_drain_needed, buf, ATAPI_MAX_DRAIN);
1117 	} else {
1118 		sdev->sector_size = ata_id_logical_sector_size(dev->id);
1119 		sdev->manage_start_stop = 1;
1120 	}
1121 
1122 	/*
1123 	 * ata_pio_sectors() expects buffer for each sector to not cross
1124 	 * page boundary.  Enforce it by requiring buffers to be sector
1125 	 * aligned, which works iff sector_size is not larger than
1126 	 * PAGE_SIZE.  ATAPI devices also need the alignment as
1127 	 * IDENTIFY_PACKET is executed as ATA_PROT_PIO.
1128 	 */
1129 	if (sdev->sector_size > PAGE_SIZE)
1130 		ata_dev_printk(dev, KERN_WARNING,
1131 			"sector_size=%u > PAGE_SIZE, PIO may malfunction\n",
1132 			sdev->sector_size);
1133 
1134 	blk_queue_update_dma_alignment(q, sdev->sector_size - 1);
1135 
1136 	if (dev->flags & ATA_DFLAG_AN)
1137 		set_bit(SDEV_EVT_MEDIA_CHANGE, sdev->supported_events);
1138 
1139 	if (dev->flags & ATA_DFLAG_NCQ) {
1140 		int depth;
1141 
1142 		depth = min(sdev->host->can_queue, ata_id_queue_depth(dev->id));
1143 		depth = min(ATA_MAX_QUEUE - 1, depth);
1144 		scsi_adjust_queue_depth(sdev, MSG_SIMPLE_TAG, depth);
1145 	}
1146 
1147 	blk_queue_flush_queueable(q, false);
1148 
1149 	dev->sdev = sdev;
1150 	return 0;
1151 }
1152 
1153 /**
1154  *	ata_scsi_slave_config - Set SCSI device attributes
1155  *	@sdev: SCSI device to examine
1156  *
1157  *	This is called before we actually start reading
1158  *	and writing to the device, to configure certain
1159  *	SCSI mid-layer behaviors.
1160  *
1161  *	LOCKING:
1162  *	Defined by SCSI layer.  We don't really care.
1163  */
1164 
1165 int ata_scsi_slave_config(struct scsi_device *sdev)
1166 {
1167 	struct ata_port *ap = ata_shost_to_port(sdev->host);
1168 	struct ata_device *dev = __ata_scsi_find_dev(ap, sdev);
1169 	int rc = 0;
1170 
1171 	ata_scsi_sdev_config(sdev);
1172 
1173 	if (dev)
1174 		rc = ata_scsi_dev_config(sdev, dev);
1175 
1176 	return rc;
1177 }
1178 
1179 /**
1180  *	ata_scsi_slave_destroy - SCSI device is about to be destroyed
1181  *	@sdev: SCSI device to be destroyed
1182  *
1183  *	@sdev is about to be destroyed for hot/warm unplugging.  If
1184  *	this unplugging was initiated by libata as indicated by NULL
1185  *	dev->sdev, this function doesn't have to do anything.
1186  *	Otherwise, SCSI layer initiated warm-unplug is in progress.
1187  *	Clear dev->sdev, schedule the device for ATA detach and invoke
1188  *	EH.
1189  *
1190  *	LOCKING:
1191  *	Defined by SCSI layer.  We don't really care.
1192  */
1193 void ata_scsi_slave_destroy(struct scsi_device *sdev)
1194 {
1195 	struct ata_port *ap = ata_shost_to_port(sdev->host);
1196 	struct request_queue *q = sdev->request_queue;
1197 	unsigned long flags;
1198 	struct ata_device *dev;
1199 
1200 	if (!ap->ops->error_handler)
1201 		return;
1202 
1203 	spin_lock_irqsave(ap->lock, flags);
1204 	dev = __ata_scsi_find_dev(ap, sdev);
1205 	if (dev && dev->sdev) {
1206 		/* SCSI device already in CANCEL state, no need to offline it */
1207 		dev->sdev = NULL;
1208 		dev->flags |= ATA_DFLAG_DETACH;
1209 		ata_port_schedule_eh(ap);
1210 	}
1211 	spin_unlock_irqrestore(ap->lock, flags);
1212 
1213 	kfree(q->dma_drain_buffer);
1214 	q->dma_drain_buffer = NULL;
1215 	q->dma_drain_size = 0;
1216 }
1217 
1218 /**
1219  *	ata_scsi_change_queue_depth - SCSI callback for queue depth config
1220  *	@sdev: SCSI device to configure queue depth for
1221  *	@queue_depth: new queue depth
1222  *	@reason: calling context
1223  *
1224  *	This is libata standard hostt->change_queue_depth callback.
1225  *	SCSI will call into this callback when user tries to set queue
1226  *	depth via sysfs.
1227  *
1228  *	LOCKING:
1229  *	SCSI layer (we don't care)
1230  *
1231  *	RETURNS:
1232  *	Newly configured queue depth.
1233  */
1234 int ata_scsi_change_queue_depth(struct scsi_device *sdev, int queue_depth,
1235 				int reason)
1236 {
1237 	struct ata_port *ap = ata_shost_to_port(sdev->host);
1238 	struct ata_device *dev;
1239 	unsigned long flags;
1240 
1241 	if (reason != SCSI_QDEPTH_DEFAULT)
1242 		return -EOPNOTSUPP;
1243 
1244 	if (queue_depth < 1 || queue_depth == sdev->queue_depth)
1245 		return sdev->queue_depth;
1246 
1247 	dev = ata_scsi_find_dev(ap, sdev);
1248 	if (!dev || !ata_dev_enabled(dev))
1249 		return sdev->queue_depth;
1250 
1251 	/* NCQ enabled? */
1252 	spin_lock_irqsave(ap->lock, flags);
1253 	dev->flags &= ~ATA_DFLAG_NCQ_OFF;
1254 	if (queue_depth == 1 || !ata_ncq_enabled(dev)) {
1255 		dev->flags |= ATA_DFLAG_NCQ_OFF;
1256 		queue_depth = 1;
1257 	}
1258 	spin_unlock_irqrestore(ap->lock, flags);
1259 
1260 	/* limit and apply queue depth */
1261 	queue_depth = min(queue_depth, sdev->host->can_queue);
1262 	queue_depth = min(queue_depth, ata_id_queue_depth(dev->id));
1263 	queue_depth = min(queue_depth, ATA_MAX_QUEUE - 1);
1264 
1265 	if (sdev->queue_depth == queue_depth)
1266 		return -EINVAL;
1267 
1268 	scsi_adjust_queue_depth(sdev, MSG_SIMPLE_TAG, queue_depth);
1269 	return queue_depth;
1270 }
1271 
1272 /**
1273  *	ata_scsi_start_stop_xlat - Translate SCSI START STOP UNIT command
1274  *	@qc: Storage for translated ATA taskfile
1275  *
1276  *	Sets up an ATA taskfile to issue STANDBY (to stop) or READ VERIFY
1277  *	(to start). Perhaps these commands should be preceded by
1278  *	CHECK POWER MODE to see what power mode the device is already in.
1279  *	[See SAT revision 5 at www.t10.org]
1280  *
1281  *	LOCKING:
1282  *	spin_lock_irqsave(host lock)
1283  *
1284  *	RETURNS:
1285  *	Zero on success, non-zero on error.
1286  */
1287 static unsigned int ata_scsi_start_stop_xlat(struct ata_queued_cmd *qc)
1288 {
1289 	struct scsi_cmnd *scmd = qc->scsicmd;
1290 	struct ata_taskfile *tf = &qc->tf;
1291 	const u8 *cdb = scmd->cmnd;
1292 
1293 	if (scmd->cmd_len < 5)
1294 		goto invalid_fld;
1295 
1296 	tf->flags |= ATA_TFLAG_DEVICE | ATA_TFLAG_ISADDR;
1297 	tf->protocol = ATA_PROT_NODATA;
1298 	if (cdb[1] & 0x1) {
1299 		;	/* ignore IMMED bit, violates sat-r05 */
1300 	}
1301 	if (cdb[4] & 0x2)
1302 		goto invalid_fld;       /* LOEJ bit set not supported */
1303 	if (((cdb[4] >> 4) & 0xf) != 0)
1304 		goto invalid_fld;       /* power conditions not supported */
1305 
1306 	if (cdb[4] & 0x1) {
1307 		tf->nsect = 1;	/* 1 sector, lba=0 */
1308 
1309 		if (qc->dev->flags & ATA_DFLAG_LBA) {
1310 			tf->flags |= ATA_TFLAG_LBA;
1311 
1312 			tf->lbah = 0x0;
1313 			tf->lbam = 0x0;
1314 			tf->lbal = 0x0;
1315 			tf->device |= ATA_LBA;
1316 		} else {
1317 			/* CHS */
1318 			tf->lbal = 0x1; /* sect */
1319 			tf->lbam = 0x0; /* cyl low */
1320 			tf->lbah = 0x0; /* cyl high */
1321 		}
1322 
1323 		tf->command = ATA_CMD_VERIFY;	/* READ VERIFY */
1324 	} else {
1325 		/* Some odd clown BIOSen issue spindown on power off (ACPI S4
1326 		 * or S5) causing some drives to spin up and down again.
1327 		 */
1328 		if ((qc->ap->flags & ATA_FLAG_NO_POWEROFF_SPINDOWN) &&
1329 		    system_state == SYSTEM_POWER_OFF)
1330 			goto skip;
1331 
1332 		if ((qc->ap->flags & ATA_FLAG_NO_HIBERNATE_SPINDOWN) &&
1333 		     system_entering_hibernation())
1334 			goto skip;
1335 
1336 		/* Issue ATA STANDBY IMMEDIATE command */
1337 		tf->command = ATA_CMD_STANDBYNOW1;
1338 	}
1339 
1340 	/*
1341 	 * Standby and Idle condition timers could be implemented but that
1342 	 * would require libata to implement the Power condition mode page
1343 	 * and allow the user to change it. Changing mode pages requires
1344 	 * MODE SELECT to be implemented.
1345 	 */
1346 
1347 	return 0;
1348 
1349  invalid_fld:
1350 	ata_scsi_set_sense(scmd, ILLEGAL_REQUEST, 0x24, 0x0);
1351 	/* "Invalid field in cbd" */
1352 	return 1;
1353  skip:
1354 	scmd->result = SAM_STAT_GOOD;
1355 	return 1;
1356 }
1357 
1358 
1359 /**
1360  *	ata_scsi_flush_xlat - Translate SCSI SYNCHRONIZE CACHE command
1361  *	@qc: Storage for translated ATA taskfile
1362  *
1363  *	Sets up an ATA taskfile to issue FLUSH CACHE or
1364  *	FLUSH CACHE EXT.
1365  *
1366  *	LOCKING:
1367  *	spin_lock_irqsave(host lock)
1368  *
1369  *	RETURNS:
1370  *	Zero on success, non-zero on error.
1371  */
1372 static unsigned int ata_scsi_flush_xlat(struct ata_queued_cmd *qc)
1373 {
1374 	struct ata_taskfile *tf = &qc->tf;
1375 
1376 	tf->flags |= ATA_TFLAG_DEVICE;
1377 	tf->protocol = ATA_PROT_NODATA;
1378 
1379 	if (qc->dev->flags & ATA_DFLAG_FLUSH_EXT)
1380 		tf->command = ATA_CMD_FLUSH_EXT;
1381 	else
1382 		tf->command = ATA_CMD_FLUSH;
1383 
1384 	/* flush is critical for IO integrity, consider it an IO command */
1385 	qc->flags |= ATA_QCFLAG_IO;
1386 
1387 	return 0;
1388 }
1389 
1390 /**
1391  *	scsi_6_lba_len - Get LBA and transfer length
1392  *	@cdb: SCSI command to translate
1393  *
1394  *	Calculate LBA and transfer length for 6-byte commands.
1395  *
1396  *	RETURNS:
1397  *	@plba: the LBA
1398  *	@plen: the transfer length
1399  */
1400 static void scsi_6_lba_len(const u8 *cdb, u64 *plba, u32 *plen)
1401 {
1402 	u64 lba = 0;
1403 	u32 len;
1404 
1405 	VPRINTK("six-byte command\n");
1406 
1407 	lba |= ((u64)(cdb[1] & 0x1f)) << 16;
1408 	lba |= ((u64)cdb[2]) << 8;
1409 	lba |= ((u64)cdb[3]);
1410 
1411 	len = cdb[4];
1412 
1413 	*plba = lba;
1414 	*plen = len;
1415 }
1416 
1417 /**
1418  *	scsi_10_lba_len - Get LBA and transfer length
1419  *	@cdb: SCSI command to translate
1420  *
1421  *	Calculate LBA and transfer length for 10-byte commands.
1422  *
1423  *	RETURNS:
1424  *	@plba: the LBA
1425  *	@plen: the transfer length
1426  */
1427 static void scsi_10_lba_len(const u8 *cdb, u64 *plba, u32 *plen)
1428 {
1429 	u64 lba = 0;
1430 	u32 len = 0;
1431 
1432 	VPRINTK("ten-byte command\n");
1433 
1434 	lba |= ((u64)cdb[2]) << 24;
1435 	lba |= ((u64)cdb[3]) << 16;
1436 	lba |= ((u64)cdb[4]) << 8;
1437 	lba |= ((u64)cdb[5]);
1438 
1439 	len |= ((u32)cdb[7]) << 8;
1440 	len |= ((u32)cdb[8]);
1441 
1442 	*plba = lba;
1443 	*plen = len;
1444 }
1445 
1446 /**
1447  *	scsi_16_lba_len - Get LBA and transfer length
1448  *	@cdb: SCSI command to translate
1449  *
1450  *	Calculate LBA and transfer length for 16-byte commands.
1451  *
1452  *	RETURNS:
1453  *	@plba: the LBA
1454  *	@plen: the transfer length
1455  */
1456 static void scsi_16_lba_len(const u8 *cdb, u64 *plba, u32 *plen)
1457 {
1458 	u64 lba = 0;
1459 	u32 len = 0;
1460 
1461 	VPRINTK("sixteen-byte command\n");
1462 
1463 	lba |= ((u64)cdb[2]) << 56;
1464 	lba |= ((u64)cdb[3]) << 48;
1465 	lba |= ((u64)cdb[4]) << 40;
1466 	lba |= ((u64)cdb[5]) << 32;
1467 	lba |= ((u64)cdb[6]) << 24;
1468 	lba |= ((u64)cdb[7]) << 16;
1469 	lba |= ((u64)cdb[8]) << 8;
1470 	lba |= ((u64)cdb[9]);
1471 
1472 	len |= ((u32)cdb[10]) << 24;
1473 	len |= ((u32)cdb[11]) << 16;
1474 	len |= ((u32)cdb[12]) << 8;
1475 	len |= ((u32)cdb[13]);
1476 
1477 	*plba = lba;
1478 	*plen = len;
1479 }
1480 
1481 /**
1482  *	ata_scsi_verify_xlat - Translate SCSI VERIFY command into an ATA one
1483  *	@qc: Storage for translated ATA taskfile
1484  *
1485  *	Converts SCSI VERIFY command to an ATA READ VERIFY command.
1486  *
1487  *	LOCKING:
1488  *	spin_lock_irqsave(host lock)
1489  *
1490  *	RETURNS:
1491  *	Zero on success, non-zero on error.
1492  */
1493 static unsigned int ata_scsi_verify_xlat(struct ata_queued_cmd *qc)
1494 {
1495 	struct scsi_cmnd *scmd = qc->scsicmd;
1496 	struct ata_taskfile *tf = &qc->tf;
1497 	struct ata_device *dev = qc->dev;
1498 	u64 dev_sectors = qc->dev->n_sectors;
1499 	const u8 *cdb = scmd->cmnd;
1500 	u64 block;
1501 	u32 n_block;
1502 
1503 	tf->flags |= ATA_TFLAG_ISADDR | ATA_TFLAG_DEVICE;
1504 	tf->protocol = ATA_PROT_NODATA;
1505 
1506 	if (cdb[0] == VERIFY) {
1507 		if (scmd->cmd_len < 10)
1508 			goto invalid_fld;
1509 		scsi_10_lba_len(cdb, &block, &n_block);
1510 	} else if (cdb[0] == VERIFY_16) {
1511 		if (scmd->cmd_len < 16)
1512 			goto invalid_fld;
1513 		scsi_16_lba_len(cdb, &block, &n_block);
1514 	} else
1515 		goto invalid_fld;
1516 
1517 	if (!n_block)
1518 		goto nothing_to_do;
1519 	if (block >= dev_sectors)
1520 		goto out_of_range;
1521 	if ((block + n_block) > dev_sectors)
1522 		goto out_of_range;
1523 
1524 	if (dev->flags & ATA_DFLAG_LBA) {
1525 		tf->flags |= ATA_TFLAG_LBA;
1526 
1527 		if (lba_28_ok(block, n_block)) {
1528 			/* use LBA28 */
1529 			tf->command = ATA_CMD_VERIFY;
1530 			tf->device |= (block >> 24) & 0xf;
1531 		} else if (lba_48_ok(block, n_block)) {
1532 			if (!(dev->flags & ATA_DFLAG_LBA48))
1533 				goto out_of_range;
1534 
1535 			/* use LBA48 */
1536 			tf->flags |= ATA_TFLAG_LBA48;
1537 			tf->command = ATA_CMD_VERIFY_EXT;
1538 
1539 			tf->hob_nsect = (n_block >> 8) & 0xff;
1540 
1541 			tf->hob_lbah = (block >> 40) & 0xff;
1542 			tf->hob_lbam = (block >> 32) & 0xff;
1543 			tf->hob_lbal = (block >> 24) & 0xff;
1544 		} else
1545 			/* request too large even for LBA48 */
1546 			goto out_of_range;
1547 
1548 		tf->nsect = n_block & 0xff;
1549 
1550 		tf->lbah = (block >> 16) & 0xff;
1551 		tf->lbam = (block >> 8) & 0xff;
1552 		tf->lbal = block & 0xff;
1553 
1554 		tf->device |= ATA_LBA;
1555 	} else {
1556 		/* CHS */
1557 		u32 sect, head, cyl, track;
1558 
1559 		if (!lba_28_ok(block, n_block))
1560 			goto out_of_range;
1561 
1562 		/* Convert LBA to CHS */
1563 		track = (u32)block / dev->sectors;
1564 		cyl   = track / dev->heads;
1565 		head  = track % dev->heads;
1566 		sect  = (u32)block % dev->sectors + 1;
1567 
1568 		DPRINTK("block %u track %u cyl %u head %u sect %u\n",
1569 			(u32)block, track, cyl, head, sect);
1570 
1571 		/* Check whether the converted CHS can fit.
1572 		   Cylinder: 0-65535
1573 		   Head: 0-15
1574 		   Sector: 1-255*/
1575 		if ((cyl >> 16) || (head >> 4) || (sect >> 8) || (!sect))
1576 			goto out_of_range;
1577 
1578 		tf->command = ATA_CMD_VERIFY;
1579 		tf->nsect = n_block & 0xff; /* Sector count 0 means 256 sectors */
1580 		tf->lbal = sect;
1581 		tf->lbam = cyl;
1582 		tf->lbah = cyl >> 8;
1583 		tf->device |= head;
1584 	}
1585 
1586 	return 0;
1587 
1588 invalid_fld:
1589 	ata_scsi_set_sense(scmd, ILLEGAL_REQUEST, 0x24, 0x0);
1590 	/* "Invalid field in cbd" */
1591 	return 1;
1592 
1593 out_of_range:
1594 	ata_scsi_set_sense(scmd, ILLEGAL_REQUEST, 0x21, 0x0);
1595 	/* "Logical Block Address out of range" */
1596 	return 1;
1597 
1598 nothing_to_do:
1599 	scmd->result = SAM_STAT_GOOD;
1600 	return 1;
1601 }
1602 
1603 /**
1604  *	ata_scsi_rw_xlat - Translate SCSI r/w command into an ATA one
1605  *	@qc: Storage for translated ATA taskfile
1606  *
1607  *	Converts any of six SCSI read/write commands into the
1608  *	ATA counterpart, including starting sector (LBA),
1609  *	sector count, and taking into account the device's LBA48
1610  *	support.
1611  *
1612  *	Commands %READ_6, %READ_10, %READ_16, %WRITE_6, %WRITE_10, and
1613  *	%WRITE_16 are currently supported.
1614  *
1615  *	LOCKING:
1616  *	spin_lock_irqsave(host lock)
1617  *
1618  *	RETURNS:
1619  *	Zero on success, non-zero on error.
1620  */
1621 static unsigned int ata_scsi_rw_xlat(struct ata_queued_cmd *qc)
1622 {
1623 	struct scsi_cmnd *scmd = qc->scsicmd;
1624 	const u8 *cdb = scmd->cmnd;
1625 	unsigned int tf_flags = 0;
1626 	u64 block;
1627 	u32 n_block;
1628 	int rc;
1629 
1630 	if (cdb[0] == WRITE_10 || cdb[0] == WRITE_6 || cdb[0] == WRITE_16)
1631 		tf_flags |= ATA_TFLAG_WRITE;
1632 
1633 	/* Calculate the SCSI LBA, transfer length and FUA. */
1634 	switch (cdb[0]) {
1635 	case READ_10:
1636 	case WRITE_10:
1637 		if (unlikely(scmd->cmd_len < 10))
1638 			goto invalid_fld;
1639 		scsi_10_lba_len(cdb, &block, &n_block);
1640 		if (unlikely(cdb[1] & (1 << 3)))
1641 			tf_flags |= ATA_TFLAG_FUA;
1642 		break;
1643 	case READ_6:
1644 	case WRITE_6:
1645 		if (unlikely(scmd->cmd_len < 6))
1646 			goto invalid_fld;
1647 		scsi_6_lba_len(cdb, &block, &n_block);
1648 
1649 		/* for 6-byte r/w commands, transfer length 0
1650 		 * means 256 blocks of data, not 0 block.
1651 		 */
1652 		if (!n_block)
1653 			n_block = 256;
1654 		break;
1655 	case READ_16:
1656 	case WRITE_16:
1657 		if (unlikely(scmd->cmd_len < 16))
1658 			goto invalid_fld;
1659 		scsi_16_lba_len(cdb, &block, &n_block);
1660 		if (unlikely(cdb[1] & (1 << 3)))
1661 			tf_flags |= ATA_TFLAG_FUA;
1662 		break;
1663 	default:
1664 		DPRINTK("no-byte command\n");
1665 		goto invalid_fld;
1666 	}
1667 
1668 	/* Check and compose ATA command */
1669 	if (!n_block)
1670 		/* For 10-byte and 16-byte SCSI R/W commands, transfer
1671 		 * length 0 means transfer 0 block of data.
1672 		 * However, for ATA R/W commands, sector count 0 means
1673 		 * 256 or 65536 sectors, not 0 sectors as in SCSI.
1674 		 *
1675 		 * WARNING: one or two older ATA drives treat 0 as 0...
1676 		 */
1677 		goto nothing_to_do;
1678 
1679 	qc->flags |= ATA_QCFLAG_IO;
1680 	qc->nbytes = n_block * scmd->device->sector_size;
1681 
1682 	rc = ata_build_rw_tf(&qc->tf, qc->dev, block, n_block, tf_flags,
1683 			     qc->tag);
1684 	if (likely(rc == 0))
1685 		return 0;
1686 
1687 	if (rc == -ERANGE)
1688 		goto out_of_range;
1689 	/* treat all other errors as -EINVAL, fall through */
1690 invalid_fld:
1691 	ata_scsi_set_sense(scmd, ILLEGAL_REQUEST, 0x24, 0x0);
1692 	/* "Invalid field in cbd" */
1693 	return 1;
1694 
1695 out_of_range:
1696 	ata_scsi_set_sense(scmd, ILLEGAL_REQUEST, 0x21, 0x0);
1697 	/* "Logical Block Address out of range" */
1698 	return 1;
1699 
1700 nothing_to_do:
1701 	scmd->result = SAM_STAT_GOOD;
1702 	return 1;
1703 }
1704 
1705 static void ata_scsi_qc_complete(struct ata_queued_cmd *qc)
1706 {
1707 	struct ata_port *ap = qc->ap;
1708 	struct scsi_cmnd *cmd = qc->scsicmd;
1709 	u8 *cdb = cmd->cmnd;
1710 	int need_sense = (qc->err_mask != 0);
1711 
1712 	/* For ATA pass thru (SAT) commands, generate a sense block if
1713 	 * user mandated it or if there's an error.  Note that if we
1714 	 * generate because the user forced us to, a check condition
1715 	 * is generated and the ATA register values are returned
1716 	 * whether the command completed successfully or not. If there
1717 	 * was no error, SK, ASC and ASCQ will all be zero.
1718 	 */
1719 	if (((cdb[0] == ATA_16) || (cdb[0] == ATA_12)) &&
1720 	    ((cdb[2] & 0x20) || need_sense)) {
1721 		ata_gen_passthru_sense(qc);
1722 	} else {
1723 		if (!need_sense) {
1724 			cmd->result = SAM_STAT_GOOD;
1725 		} else {
1726 			/* TODO: decide which descriptor format to use
1727 			 * for 48b LBA devices and call that here
1728 			 * instead of the fixed desc, which is only
1729 			 * good for smaller LBA (and maybe CHS?)
1730 			 * devices.
1731 			 */
1732 			ata_gen_ata_sense(qc);
1733 		}
1734 	}
1735 
1736 	if (need_sense && !ap->ops->error_handler)
1737 		ata_dump_status(ap->print_id, &qc->result_tf);
1738 
1739 	qc->scsidone(cmd);
1740 
1741 	ata_qc_free(qc);
1742 }
1743 
1744 /**
1745  *	ata_scsi_translate - Translate then issue SCSI command to ATA device
1746  *	@dev: ATA device to which the command is addressed
1747  *	@cmd: SCSI command to execute
1748  *	@xlat_func: Actor which translates @cmd to an ATA taskfile
1749  *
1750  *	Our ->queuecommand() function has decided that the SCSI
1751  *	command issued can be directly translated into an ATA
1752  *	command, rather than handled internally.
1753  *
1754  *	This function sets up an ata_queued_cmd structure for the
1755  *	SCSI command, and sends that ata_queued_cmd to the hardware.
1756  *
1757  *	The xlat_func argument (actor) returns 0 if ready to execute
1758  *	ATA command, else 1 to finish translation. If 1 is returned
1759  *	then cmd->result (and possibly cmd->sense_buffer) are assumed
1760  *	to be set reflecting an error condition or clean (early)
1761  *	termination.
1762  *
1763  *	LOCKING:
1764  *	spin_lock_irqsave(host lock)
1765  *
1766  *	RETURNS:
1767  *	0 on success, SCSI_ML_QUEUE_DEVICE_BUSY if the command
1768  *	needs to be deferred.
1769  */
1770 static int ata_scsi_translate(struct ata_device *dev, struct scsi_cmnd *cmd,
1771 			      ata_xlat_func_t xlat_func)
1772 {
1773 	struct ata_port *ap = dev->link->ap;
1774 	struct ata_queued_cmd *qc;
1775 	int rc;
1776 
1777 	VPRINTK("ENTER\n");
1778 
1779 	qc = ata_scsi_qc_new(dev, cmd);
1780 	if (!qc)
1781 		goto err_mem;
1782 
1783 	/* data is present; dma-map it */
1784 	if (cmd->sc_data_direction == DMA_FROM_DEVICE ||
1785 	    cmd->sc_data_direction == DMA_TO_DEVICE) {
1786 		if (unlikely(scsi_bufflen(cmd) < 1)) {
1787 			ata_dev_printk(dev, KERN_WARNING,
1788 				       "WARNING: zero len r/w req\n");
1789 			goto err_did;
1790 		}
1791 
1792 		ata_sg_init(qc, scsi_sglist(cmd), scsi_sg_count(cmd));
1793 
1794 		qc->dma_dir = cmd->sc_data_direction;
1795 	}
1796 
1797 	qc->complete_fn = ata_scsi_qc_complete;
1798 
1799 	if (xlat_func(qc))
1800 		goto early_finish;
1801 
1802 	if (ap->ops->qc_defer) {
1803 		if ((rc = ap->ops->qc_defer(qc)))
1804 			goto defer;
1805 	}
1806 
1807 	/* select device, send command to hardware */
1808 	ata_qc_issue(qc);
1809 
1810 	VPRINTK("EXIT\n");
1811 	return 0;
1812 
1813 early_finish:
1814 	ata_qc_free(qc);
1815 	cmd->scsi_done(cmd);
1816 	DPRINTK("EXIT - early finish (good or error)\n");
1817 	return 0;
1818 
1819 err_did:
1820 	ata_qc_free(qc);
1821 	cmd->result = (DID_ERROR << 16);
1822 	cmd->scsi_done(cmd);
1823 err_mem:
1824 	DPRINTK("EXIT - internal\n");
1825 	return 0;
1826 
1827 defer:
1828 	ata_qc_free(qc);
1829 	DPRINTK("EXIT - defer\n");
1830 	if (rc == ATA_DEFER_LINK)
1831 		return SCSI_MLQUEUE_DEVICE_BUSY;
1832 	else
1833 		return SCSI_MLQUEUE_HOST_BUSY;
1834 }
1835 
1836 /**
1837  *	ata_scsi_rbuf_get - Map response buffer.
1838  *	@cmd: SCSI command containing buffer to be mapped.
1839  *	@flags: unsigned long variable to store irq enable status
1840  *	@copy_in: copy in from user buffer
1841  *
1842  *	Prepare buffer for simulated SCSI commands.
1843  *
1844  *	LOCKING:
1845  *	spin_lock_irqsave(ata_scsi_rbuf_lock) on success
1846  *
1847  *	RETURNS:
1848  *	Pointer to response buffer.
1849  */
1850 static void *ata_scsi_rbuf_get(struct scsi_cmnd *cmd, bool copy_in,
1851 			       unsigned long *flags)
1852 {
1853 	spin_lock_irqsave(&ata_scsi_rbuf_lock, *flags);
1854 
1855 	memset(ata_scsi_rbuf, 0, ATA_SCSI_RBUF_SIZE);
1856 	if (copy_in)
1857 		sg_copy_to_buffer(scsi_sglist(cmd), scsi_sg_count(cmd),
1858 				  ata_scsi_rbuf, ATA_SCSI_RBUF_SIZE);
1859 	return ata_scsi_rbuf;
1860 }
1861 
1862 /**
1863  *	ata_scsi_rbuf_put - Unmap response buffer.
1864  *	@cmd: SCSI command containing buffer to be unmapped.
1865  *	@copy_out: copy out result
1866  *	@flags: @flags passed to ata_scsi_rbuf_get()
1867  *
1868  *	Returns rbuf buffer.  The result is copied to @cmd's buffer if
1869  *	@copy_back is true.
1870  *
1871  *	LOCKING:
1872  *	Unlocks ata_scsi_rbuf_lock.
1873  */
1874 static inline void ata_scsi_rbuf_put(struct scsi_cmnd *cmd, bool copy_out,
1875 				     unsigned long *flags)
1876 {
1877 	if (copy_out)
1878 		sg_copy_from_buffer(scsi_sglist(cmd), scsi_sg_count(cmd),
1879 				    ata_scsi_rbuf, ATA_SCSI_RBUF_SIZE);
1880 	spin_unlock_irqrestore(&ata_scsi_rbuf_lock, *flags);
1881 }
1882 
1883 /**
1884  *	ata_scsi_rbuf_fill - wrapper for SCSI command simulators
1885  *	@args: device IDENTIFY data / SCSI command of interest.
1886  *	@actor: Callback hook for desired SCSI command simulator
1887  *
1888  *	Takes care of the hard work of simulating a SCSI command...
1889  *	Mapping the response buffer, calling the command's handler,
1890  *	and handling the handler's return value.  This return value
1891  *	indicates whether the handler wishes the SCSI command to be
1892  *	completed successfully (0), or not (in which case cmd->result
1893  *	and sense buffer are assumed to be set).
1894  *
1895  *	LOCKING:
1896  *	spin_lock_irqsave(host lock)
1897  */
1898 static void ata_scsi_rbuf_fill(struct ata_scsi_args *args,
1899 		unsigned int (*actor)(struct ata_scsi_args *args, u8 *rbuf))
1900 {
1901 	u8 *rbuf;
1902 	unsigned int rc;
1903 	struct scsi_cmnd *cmd = args->cmd;
1904 	unsigned long flags;
1905 
1906 	rbuf = ata_scsi_rbuf_get(cmd, false, &flags);
1907 	rc = actor(args, rbuf);
1908 	ata_scsi_rbuf_put(cmd, rc == 0, &flags);
1909 
1910 	if (rc == 0)
1911 		cmd->result = SAM_STAT_GOOD;
1912 	args->done(cmd);
1913 }
1914 
1915 /**
1916  *	ata_scsiop_inq_std - Simulate INQUIRY command
1917  *	@args: device IDENTIFY data / SCSI command of interest.
1918  *	@rbuf: Response buffer, to which simulated SCSI cmd output is sent.
1919  *
1920  *	Returns standard device identification data associated
1921  *	with non-VPD INQUIRY command output.
1922  *
1923  *	LOCKING:
1924  *	spin_lock_irqsave(host lock)
1925  */
1926 static unsigned int ata_scsiop_inq_std(struct ata_scsi_args *args, u8 *rbuf)
1927 {
1928 	const u8 versions[] = {
1929 		0x60,	/* SAM-3 (no version claimed) */
1930 
1931 		0x03,
1932 		0x20,	/* SBC-2 (no version claimed) */
1933 
1934 		0x02,
1935 		0x60	/* SPC-3 (no version claimed) */
1936 	};
1937 	u8 hdr[] = {
1938 		TYPE_DISK,
1939 		0,
1940 		0x5,	/* claim SPC-3 version compatibility */
1941 		2,
1942 		95 - 4
1943 	};
1944 
1945 	VPRINTK("ENTER\n");
1946 
1947 	/* set scsi removeable (RMB) bit per ata bit */
1948 	if (ata_id_removeable(args->id))
1949 		hdr[1] |= (1 << 7);
1950 
1951 	memcpy(rbuf, hdr, sizeof(hdr));
1952 	memcpy(&rbuf[8], "ATA     ", 8);
1953 	ata_id_string(args->id, &rbuf[16], ATA_ID_PROD, 16);
1954 	ata_id_string(args->id, &rbuf[32], ATA_ID_FW_REV, 4);
1955 
1956 	if (rbuf[32] == 0 || rbuf[32] == ' ')
1957 		memcpy(&rbuf[32], "n/a ", 4);
1958 
1959 	memcpy(rbuf + 59, versions, sizeof(versions));
1960 
1961 	return 0;
1962 }
1963 
1964 /**
1965  *	ata_scsiop_inq_00 - Simulate INQUIRY VPD page 0, list of pages
1966  *	@args: device IDENTIFY data / SCSI command of interest.
1967  *	@rbuf: Response buffer, to which simulated SCSI cmd output is sent.
1968  *
1969  *	Returns list of inquiry VPD pages available.
1970  *
1971  *	LOCKING:
1972  *	spin_lock_irqsave(host lock)
1973  */
1974 static unsigned int ata_scsiop_inq_00(struct ata_scsi_args *args, u8 *rbuf)
1975 {
1976 	const u8 pages[] = {
1977 		0x00,	/* page 0x00, this page */
1978 		0x80,	/* page 0x80, unit serial no page */
1979 		0x83,	/* page 0x83, device ident page */
1980 		0x89,	/* page 0x89, ata info page */
1981 		0xb0,	/* page 0xb0, block limits page */
1982 		0xb1,	/* page 0xb1, block device characteristics page */
1983 		0xb2,	/* page 0xb2, thin provisioning page */
1984 	};
1985 
1986 	rbuf[3] = sizeof(pages);	/* number of supported VPD pages */
1987 	memcpy(rbuf + 4, pages, sizeof(pages));
1988 	return 0;
1989 }
1990 
1991 /**
1992  *	ata_scsiop_inq_80 - Simulate INQUIRY VPD page 80, device serial number
1993  *	@args: device IDENTIFY data / SCSI command of interest.
1994  *	@rbuf: Response buffer, to which simulated SCSI cmd output is sent.
1995  *
1996  *	Returns ATA device serial number.
1997  *
1998  *	LOCKING:
1999  *	spin_lock_irqsave(host lock)
2000  */
2001 static unsigned int ata_scsiop_inq_80(struct ata_scsi_args *args, u8 *rbuf)
2002 {
2003 	const u8 hdr[] = {
2004 		0,
2005 		0x80,			/* this page code */
2006 		0,
2007 		ATA_ID_SERNO_LEN,	/* page len */
2008 	};
2009 
2010 	memcpy(rbuf, hdr, sizeof(hdr));
2011 	ata_id_string(args->id, (unsigned char *) &rbuf[4],
2012 		      ATA_ID_SERNO, ATA_ID_SERNO_LEN);
2013 	return 0;
2014 }
2015 
2016 /**
2017  *	ata_scsiop_inq_83 - Simulate INQUIRY VPD page 83, device identity
2018  *	@args: device IDENTIFY data / SCSI command of interest.
2019  *	@rbuf: Response buffer, to which simulated SCSI cmd output is sent.
2020  *
2021  *	Yields two logical unit device identification designators:
2022  *	 - vendor specific ASCII containing the ATA serial number
2023  *	 - SAT defined "t10 vendor id based" containing ASCII vendor
2024  *	   name ("ATA     "), model and serial numbers.
2025  *
2026  *	LOCKING:
2027  *	spin_lock_irqsave(host lock)
2028  */
2029 static unsigned int ata_scsiop_inq_83(struct ata_scsi_args *args, u8 *rbuf)
2030 {
2031 	const int sat_model_serial_desc_len = 68;
2032 	int num;
2033 
2034 	rbuf[1] = 0x83;			/* this page code */
2035 	num = 4;
2036 
2037 	/* piv=0, assoc=lu, code_set=ACSII, designator=vendor */
2038 	rbuf[num + 0] = 2;
2039 	rbuf[num + 3] = ATA_ID_SERNO_LEN;
2040 	num += 4;
2041 	ata_id_string(args->id, (unsigned char *) rbuf + num,
2042 		      ATA_ID_SERNO, ATA_ID_SERNO_LEN);
2043 	num += ATA_ID_SERNO_LEN;
2044 
2045 	/* SAT defined lu model and serial numbers descriptor */
2046 	/* piv=0, assoc=lu, code_set=ACSII, designator=t10 vendor id */
2047 	rbuf[num + 0] = 2;
2048 	rbuf[num + 1] = 1;
2049 	rbuf[num + 3] = sat_model_serial_desc_len;
2050 	num += 4;
2051 	memcpy(rbuf + num, "ATA     ", 8);
2052 	num += 8;
2053 	ata_id_string(args->id, (unsigned char *) rbuf + num, ATA_ID_PROD,
2054 		      ATA_ID_PROD_LEN);
2055 	num += ATA_ID_PROD_LEN;
2056 	ata_id_string(args->id, (unsigned char *) rbuf + num, ATA_ID_SERNO,
2057 		      ATA_ID_SERNO_LEN);
2058 	num += ATA_ID_SERNO_LEN;
2059 
2060 	if (ata_id_has_wwn(args->id)) {
2061 		/* SAT defined lu world wide name */
2062 		/* piv=0, assoc=lu, code_set=binary, designator=NAA */
2063 		rbuf[num + 0] = 1;
2064 		rbuf[num + 1] = 3;
2065 		rbuf[num + 3] = ATA_ID_WWN_LEN;
2066 		num += 4;
2067 		ata_id_string(args->id, (unsigned char *) rbuf + num,
2068 			      ATA_ID_WWN, ATA_ID_WWN_LEN);
2069 		num += ATA_ID_WWN_LEN;
2070 	}
2071 	rbuf[3] = num - 4;    /* page len (assume less than 256 bytes) */
2072 	return 0;
2073 }
2074 
2075 /**
2076  *	ata_scsiop_inq_89 - Simulate INQUIRY VPD page 89, ATA info
2077  *	@args: device IDENTIFY data / SCSI command of interest.
2078  *	@rbuf: Response buffer, to which simulated SCSI cmd output is sent.
2079  *
2080  *	Yields SAT-specified ATA VPD page.
2081  *
2082  *	LOCKING:
2083  *	spin_lock_irqsave(host lock)
2084  */
2085 static unsigned int ata_scsiop_inq_89(struct ata_scsi_args *args, u8 *rbuf)
2086 {
2087 	struct ata_taskfile tf;
2088 
2089 	memset(&tf, 0, sizeof(tf));
2090 
2091 	rbuf[1] = 0x89;			/* our page code */
2092 	rbuf[2] = (0x238 >> 8);		/* page size fixed at 238h */
2093 	rbuf[3] = (0x238 & 0xff);
2094 
2095 	memcpy(&rbuf[8], "linux   ", 8);
2096 	memcpy(&rbuf[16], "libata          ", 16);
2097 	memcpy(&rbuf[32], DRV_VERSION, 4);
2098 	ata_id_string(args->id, &rbuf[32], ATA_ID_FW_REV, 4);
2099 
2100 	/* we don't store the ATA device signature, so we fake it */
2101 
2102 	tf.command = ATA_DRDY;		/* really, this is Status reg */
2103 	tf.lbal = 0x1;
2104 	tf.nsect = 0x1;
2105 
2106 	ata_tf_to_fis(&tf, 0, 1, &rbuf[36]);	/* TODO: PMP? */
2107 	rbuf[36] = 0x34;		/* force D2H Reg FIS (34h) */
2108 
2109 	rbuf[56] = ATA_CMD_ID_ATA;
2110 
2111 	memcpy(&rbuf[60], &args->id[0], 512);
2112 	return 0;
2113 }
2114 
2115 static unsigned int ata_scsiop_inq_b0(struct ata_scsi_args *args, u8 *rbuf)
2116 {
2117 	u16 min_io_sectors;
2118 
2119 	rbuf[1] = 0xb0;
2120 	rbuf[3] = 0x3c;		/* required VPD size with unmap support */
2121 
2122 	/*
2123 	 * Optimal transfer length granularity.
2124 	 *
2125 	 * This is always one physical block, but for disks with a smaller
2126 	 * logical than physical sector size we need to figure out what the
2127 	 * latter is.
2128 	 */
2129 	min_io_sectors = 1 << ata_id_log2_per_physical_sector(args->id);
2130 	put_unaligned_be16(min_io_sectors, &rbuf[6]);
2131 
2132 	/*
2133 	 * Optimal unmap granularity.
2134 	 *
2135 	 * The ATA spec doesn't even know about a granularity or alignment
2136 	 * for the TRIM command.  We can leave away most of the unmap related
2137 	 * VPD page entries, but we have specifify a granularity to signal
2138 	 * that we support some form of unmap - in thise case via WRITE SAME
2139 	 * with the unmap bit set.
2140 	 */
2141 	if (ata_id_has_trim(args->id)) {
2142 		put_unaligned_be64(65535 * 512 / 8, &rbuf[36]);
2143 		put_unaligned_be32(1, &rbuf[28]);
2144 	}
2145 
2146 	return 0;
2147 }
2148 
2149 static unsigned int ata_scsiop_inq_b1(struct ata_scsi_args *args, u8 *rbuf)
2150 {
2151 	int form_factor = ata_id_form_factor(args->id);
2152 	int media_rotation_rate = ata_id_rotation_rate(args->id);
2153 
2154 	rbuf[1] = 0xb1;
2155 	rbuf[3] = 0x3c;
2156 	rbuf[4] = media_rotation_rate >> 8;
2157 	rbuf[5] = media_rotation_rate;
2158 	rbuf[7] = form_factor;
2159 
2160 	return 0;
2161 }
2162 
2163 static unsigned int ata_scsiop_inq_b2(struct ata_scsi_args *args, u8 *rbuf)
2164 {
2165 	/* SCSI Thin Provisioning VPD page: SBC-3 rev 22 or later */
2166 	rbuf[1] = 0xb2;
2167 	rbuf[3] = 0x4;
2168 	rbuf[5] = 1 << 6;	/* TPWS */
2169 
2170 	return 0;
2171 }
2172 
2173 /**
2174  *	ata_scsiop_noop - Command handler that simply returns success.
2175  *	@args: device IDENTIFY data / SCSI command of interest.
2176  *	@rbuf: Response buffer, to which simulated SCSI cmd output is sent.
2177  *
2178  *	No operation.  Simply returns success to caller, to indicate
2179  *	that the caller should successfully complete this SCSI command.
2180  *
2181  *	LOCKING:
2182  *	spin_lock_irqsave(host lock)
2183  */
2184 static unsigned int ata_scsiop_noop(struct ata_scsi_args *args, u8 *rbuf)
2185 {
2186 	VPRINTK("ENTER\n");
2187 	return 0;
2188 }
2189 
2190 /**
2191  *	ata_msense_caching - Simulate MODE SENSE caching info page
2192  *	@id: device IDENTIFY data
2193  *	@buf: output buffer
2194  *
2195  *	Generate a caching info page, which conditionally indicates
2196  *	write caching to the SCSI layer, depending on device
2197  *	capabilities.
2198  *
2199  *	LOCKING:
2200  *	None.
2201  */
2202 static unsigned int ata_msense_caching(u16 *id, u8 *buf)
2203 {
2204 	memcpy(buf, def_cache_mpage, sizeof(def_cache_mpage));
2205 	if (ata_id_wcache_enabled(id))
2206 		buf[2] |= (1 << 2);	/* write cache enable */
2207 	if (!ata_id_rahead_enabled(id))
2208 		buf[12] |= (1 << 5);	/* disable read ahead */
2209 	return sizeof(def_cache_mpage);
2210 }
2211 
2212 /**
2213  *	ata_msense_ctl_mode - Simulate MODE SENSE control mode page
2214  *	@buf: output buffer
2215  *
2216  *	Generate a generic MODE SENSE control mode page.
2217  *
2218  *	LOCKING:
2219  *	None.
2220  */
2221 static unsigned int ata_msense_ctl_mode(u8 *buf)
2222 {
2223 	memcpy(buf, def_control_mpage, sizeof(def_control_mpage));
2224 	return sizeof(def_control_mpage);
2225 }
2226 
2227 /**
2228  *	ata_msense_rw_recovery - Simulate MODE SENSE r/w error recovery page
2229  *	@buf: output buffer
2230  *
2231  *	Generate a generic MODE SENSE r/w error recovery page.
2232  *
2233  *	LOCKING:
2234  *	None.
2235  */
2236 static unsigned int ata_msense_rw_recovery(u8 *buf)
2237 {
2238 	memcpy(buf, def_rw_recovery_mpage, sizeof(def_rw_recovery_mpage));
2239 	return sizeof(def_rw_recovery_mpage);
2240 }
2241 
2242 /*
2243  * We can turn this into a real blacklist if it's needed, for now just
2244  * blacklist any Maxtor BANC1G10 revision firmware
2245  */
2246 static int ata_dev_supports_fua(u16 *id)
2247 {
2248 	unsigned char model[ATA_ID_PROD_LEN + 1], fw[ATA_ID_FW_REV_LEN + 1];
2249 
2250 	if (!libata_fua)
2251 		return 0;
2252 	if (!ata_id_has_fua(id))
2253 		return 0;
2254 
2255 	ata_id_c_string(id, model, ATA_ID_PROD, sizeof(model));
2256 	ata_id_c_string(id, fw, ATA_ID_FW_REV, sizeof(fw));
2257 
2258 	if (strcmp(model, "Maxtor"))
2259 		return 1;
2260 	if (strcmp(fw, "BANC1G10"))
2261 		return 1;
2262 
2263 	return 0; /* blacklisted */
2264 }
2265 
2266 /**
2267  *	ata_scsiop_mode_sense - Simulate MODE SENSE 6, 10 commands
2268  *	@args: device IDENTIFY data / SCSI command of interest.
2269  *	@rbuf: Response buffer, to which simulated SCSI cmd output is sent.
2270  *
2271  *	Simulate MODE SENSE commands. Assume this is invoked for direct
2272  *	access devices (e.g. disks) only. There should be no block
2273  *	descriptor for other device types.
2274  *
2275  *	LOCKING:
2276  *	spin_lock_irqsave(host lock)
2277  */
2278 static unsigned int ata_scsiop_mode_sense(struct ata_scsi_args *args, u8 *rbuf)
2279 {
2280 	struct ata_device *dev = args->dev;
2281 	u8 *scsicmd = args->cmd->cmnd, *p = rbuf;
2282 	const u8 sat_blk_desc[] = {
2283 		0, 0, 0, 0,	/* number of blocks: sat unspecified */
2284 		0,
2285 		0, 0x2, 0x0	/* block length: 512 bytes */
2286 	};
2287 	u8 pg, spg;
2288 	unsigned int ebd, page_control, six_byte;
2289 	u8 dpofua;
2290 
2291 	VPRINTK("ENTER\n");
2292 
2293 	six_byte = (scsicmd[0] == MODE_SENSE);
2294 	ebd = !(scsicmd[1] & 0x8);      /* dbd bit inverted == edb */
2295 	/*
2296 	 * LLBA bit in msense(10) ignored (compliant)
2297 	 */
2298 
2299 	page_control = scsicmd[2] >> 6;
2300 	switch (page_control) {
2301 	case 0: /* current */
2302 		break;  /* supported */
2303 	case 3: /* saved */
2304 		goto saving_not_supp;
2305 	case 1: /* changeable */
2306 	case 2: /* defaults */
2307 	default:
2308 		goto invalid_fld;
2309 	}
2310 
2311 	if (six_byte)
2312 		p += 4 + (ebd ? 8 : 0);
2313 	else
2314 		p += 8 + (ebd ? 8 : 0);
2315 
2316 	pg = scsicmd[2] & 0x3f;
2317 	spg = scsicmd[3];
2318 	/*
2319 	 * No mode subpages supported (yet) but asking for _all_
2320 	 * subpages may be valid
2321 	 */
2322 	if (spg && (spg != ALL_SUB_MPAGES))
2323 		goto invalid_fld;
2324 
2325 	switch(pg) {
2326 	case RW_RECOVERY_MPAGE:
2327 		p += ata_msense_rw_recovery(p);
2328 		break;
2329 
2330 	case CACHE_MPAGE:
2331 		p += ata_msense_caching(args->id, p);
2332 		break;
2333 
2334 	case CONTROL_MPAGE:
2335 		p += ata_msense_ctl_mode(p);
2336 		break;
2337 
2338 	case ALL_MPAGES:
2339 		p += ata_msense_rw_recovery(p);
2340 		p += ata_msense_caching(args->id, p);
2341 		p += ata_msense_ctl_mode(p);
2342 		break;
2343 
2344 	default:		/* invalid page code */
2345 		goto invalid_fld;
2346 	}
2347 
2348 	dpofua = 0;
2349 	if (ata_dev_supports_fua(args->id) && (dev->flags & ATA_DFLAG_LBA48) &&
2350 	    (!(dev->flags & ATA_DFLAG_PIO) || dev->multi_count))
2351 		dpofua = 1 << 4;
2352 
2353 	if (six_byte) {
2354 		rbuf[0] = p - rbuf - 1;
2355 		rbuf[2] |= dpofua;
2356 		if (ebd) {
2357 			rbuf[3] = sizeof(sat_blk_desc);
2358 			memcpy(rbuf + 4, sat_blk_desc, sizeof(sat_blk_desc));
2359 		}
2360 	} else {
2361 		unsigned int output_len = p - rbuf - 2;
2362 
2363 		rbuf[0] = output_len >> 8;
2364 		rbuf[1] = output_len;
2365 		rbuf[3] |= dpofua;
2366 		if (ebd) {
2367 			rbuf[7] = sizeof(sat_blk_desc);
2368 			memcpy(rbuf + 8, sat_blk_desc, sizeof(sat_blk_desc));
2369 		}
2370 	}
2371 	return 0;
2372 
2373 invalid_fld:
2374 	ata_scsi_set_sense(args->cmd, ILLEGAL_REQUEST, 0x24, 0x0);
2375 	/* "Invalid field in cbd" */
2376 	return 1;
2377 
2378 saving_not_supp:
2379 	ata_scsi_set_sense(args->cmd, ILLEGAL_REQUEST, 0x39, 0x0);
2380 	 /* "Saving parameters not supported" */
2381 	return 1;
2382 }
2383 
2384 /**
2385  *	ata_scsiop_read_cap - Simulate READ CAPACITY[ 16] commands
2386  *	@args: device IDENTIFY data / SCSI command of interest.
2387  *	@rbuf: Response buffer, to which simulated SCSI cmd output is sent.
2388  *
2389  *	Simulate READ CAPACITY commands.
2390  *
2391  *	LOCKING:
2392  *	None.
2393  */
2394 static unsigned int ata_scsiop_read_cap(struct ata_scsi_args *args, u8 *rbuf)
2395 {
2396 	struct ata_device *dev = args->dev;
2397 	u64 last_lba = dev->n_sectors - 1; /* LBA of the last block */
2398 	u32 sector_size; /* physical sector size in bytes */
2399 	u8 log2_per_phys;
2400 	u16 lowest_aligned;
2401 
2402 	sector_size = ata_id_logical_sector_size(dev->id);
2403 	log2_per_phys = ata_id_log2_per_physical_sector(dev->id);
2404 	lowest_aligned = ata_id_logical_sector_offset(dev->id, log2_per_phys);
2405 
2406 	VPRINTK("ENTER\n");
2407 
2408 	if (args->cmd->cmnd[0] == READ_CAPACITY) {
2409 		if (last_lba >= 0xffffffffULL)
2410 			last_lba = 0xffffffff;
2411 
2412 		/* sector count, 32-bit */
2413 		rbuf[0] = last_lba >> (8 * 3);
2414 		rbuf[1] = last_lba >> (8 * 2);
2415 		rbuf[2] = last_lba >> (8 * 1);
2416 		rbuf[3] = last_lba;
2417 
2418 		/* sector size */
2419 		rbuf[4] = sector_size >> (8 * 3);
2420 		rbuf[5] = sector_size >> (8 * 2);
2421 		rbuf[6] = sector_size >> (8 * 1);
2422 		rbuf[7] = sector_size;
2423 	} else {
2424 		/* sector count, 64-bit */
2425 		rbuf[0] = last_lba >> (8 * 7);
2426 		rbuf[1] = last_lba >> (8 * 6);
2427 		rbuf[2] = last_lba >> (8 * 5);
2428 		rbuf[3] = last_lba >> (8 * 4);
2429 		rbuf[4] = last_lba >> (8 * 3);
2430 		rbuf[5] = last_lba >> (8 * 2);
2431 		rbuf[6] = last_lba >> (8 * 1);
2432 		rbuf[7] = last_lba;
2433 
2434 		/* sector size */
2435 		rbuf[ 8] = sector_size >> (8 * 3);
2436 		rbuf[ 9] = sector_size >> (8 * 2);
2437 		rbuf[10] = sector_size >> (8 * 1);
2438 		rbuf[11] = sector_size;
2439 
2440 		rbuf[12] = 0;
2441 		rbuf[13] = log2_per_phys;
2442 		rbuf[14] = (lowest_aligned >> 8) & 0x3f;
2443 		rbuf[15] = lowest_aligned;
2444 
2445 		if (ata_id_has_trim(args->id)) {
2446 			rbuf[14] |= 0x80; /* TPE */
2447 
2448 			if (ata_id_has_zero_after_trim(args->id))
2449 				rbuf[14] |= 0x40; /* TPRZ */
2450 		}
2451 	}
2452 
2453 	return 0;
2454 }
2455 
2456 /**
2457  *	ata_scsiop_report_luns - Simulate REPORT LUNS command
2458  *	@args: device IDENTIFY data / SCSI command of interest.
2459  *	@rbuf: Response buffer, to which simulated SCSI cmd output is sent.
2460  *
2461  *	Simulate REPORT LUNS command.
2462  *
2463  *	LOCKING:
2464  *	spin_lock_irqsave(host lock)
2465  */
2466 static unsigned int ata_scsiop_report_luns(struct ata_scsi_args *args, u8 *rbuf)
2467 {
2468 	VPRINTK("ENTER\n");
2469 	rbuf[3] = 8;	/* just one lun, LUN 0, size 8 bytes */
2470 
2471 	return 0;
2472 }
2473 
2474 static void atapi_sense_complete(struct ata_queued_cmd *qc)
2475 {
2476 	if (qc->err_mask && ((qc->err_mask & AC_ERR_DEV) == 0)) {
2477 		/* FIXME: not quite right; we don't want the
2478 		 * translation of taskfile registers into
2479 		 * a sense descriptors, since that's only
2480 		 * correct for ATA, not ATAPI
2481 		 */
2482 		ata_gen_passthru_sense(qc);
2483 	}
2484 
2485 	qc->scsidone(qc->scsicmd);
2486 	ata_qc_free(qc);
2487 }
2488 
2489 /* is it pointless to prefer PIO for "safety reasons"? */
2490 static inline int ata_pio_use_silly(struct ata_port *ap)
2491 {
2492 	return (ap->flags & ATA_FLAG_PIO_DMA);
2493 }
2494 
2495 static void atapi_request_sense(struct ata_queued_cmd *qc)
2496 {
2497 	struct ata_port *ap = qc->ap;
2498 	struct scsi_cmnd *cmd = qc->scsicmd;
2499 
2500 	DPRINTK("ATAPI request sense\n");
2501 
2502 	/* FIXME: is this needed? */
2503 	memset(cmd->sense_buffer, 0, SCSI_SENSE_BUFFERSIZE);
2504 
2505 #ifdef CONFIG_ATA_SFF
2506 	if (ap->ops->sff_tf_read)
2507 		ap->ops->sff_tf_read(ap, &qc->tf);
2508 #endif
2509 
2510 	/* fill these in, for the case where they are -not- overwritten */
2511 	cmd->sense_buffer[0] = 0x70;
2512 	cmd->sense_buffer[2] = qc->tf.feature >> 4;
2513 
2514 	ata_qc_reinit(qc);
2515 
2516 	/* setup sg table and init transfer direction */
2517 	sg_init_one(&qc->sgent, cmd->sense_buffer, SCSI_SENSE_BUFFERSIZE);
2518 	ata_sg_init(qc, &qc->sgent, 1);
2519 	qc->dma_dir = DMA_FROM_DEVICE;
2520 
2521 	memset(&qc->cdb, 0, qc->dev->cdb_len);
2522 	qc->cdb[0] = REQUEST_SENSE;
2523 	qc->cdb[4] = SCSI_SENSE_BUFFERSIZE;
2524 
2525 	qc->tf.flags |= ATA_TFLAG_ISADDR | ATA_TFLAG_DEVICE;
2526 	qc->tf.command = ATA_CMD_PACKET;
2527 
2528 	if (ata_pio_use_silly(ap)) {
2529 		qc->tf.protocol = ATAPI_PROT_DMA;
2530 		qc->tf.feature |= ATAPI_PKT_DMA;
2531 	} else {
2532 		qc->tf.protocol = ATAPI_PROT_PIO;
2533 		qc->tf.lbam = SCSI_SENSE_BUFFERSIZE;
2534 		qc->tf.lbah = 0;
2535 	}
2536 	qc->nbytes = SCSI_SENSE_BUFFERSIZE;
2537 
2538 	qc->complete_fn = atapi_sense_complete;
2539 
2540 	ata_qc_issue(qc);
2541 
2542 	DPRINTK("EXIT\n");
2543 }
2544 
2545 static void atapi_qc_complete(struct ata_queued_cmd *qc)
2546 {
2547 	struct scsi_cmnd *cmd = qc->scsicmd;
2548 	unsigned int err_mask = qc->err_mask;
2549 
2550 	VPRINTK("ENTER, err_mask 0x%X\n", err_mask);
2551 
2552 	/* handle completion from new EH */
2553 	if (unlikely(qc->ap->ops->error_handler &&
2554 		     (err_mask || qc->flags & ATA_QCFLAG_SENSE_VALID))) {
2555 
2556 		if (!(qc->flags & ATA_QCFLAG_SENSE_VALID)) {
2557 			/* FIXME: not quite right; we don't want the
2558 			 * translation of taskfile registers into a
2559 			 * sense descriptors, since that's only
2560 			 * correct for ATA, not ATAPI
2561 			 */
2562 			ata_gen_passthru_sense(qc);
2563 		}
2564 
2565 		/* SCSI EH automatically locks door if sdev->locked is
2566 		 * set.  Sometimes door lock request continues to
2567 		 * fail, for example, when no media is present.  This
2568 		 * creates a loop - SCSI EH issues door lock which
2569 		 * fails and gets invoked again to acquire sense data
2570 		 * for the failed command.
2571 		 *
2572 		 * If door lock fails, always clear sdev->locked to
2573 		 * avoid this infinite loop.
2574 		 *
2575 		 * This may happen before SCSI scan is complete.  Make
2576 		 * sure qc->dev->sdev isn't NULL before dereferencing.
2577 		 */
2578 		if (qc->cdb[0] == ALLOW_MEDIUM_REMOVAL && qc->dev->sdev)
2579 			qc->dev->sdev->locked = 0;
2580 
2581 		qc->scsicmd->result = SAM_STAT_CHECK_CONDITION;
2582 		qc->scsidone(cmd);
2583 		ata_qc_free(qc);
2584 		return;
2585 	}
2586 
2587 	/* successful completion or old EH failure path */
2588 	if (unlikely(err_mask & AC_ERR_DEV)) {
2589 		cmd->result = SAM_STAT_CHECK_CONDITION;
2590 		atapi_request_sense(qc);
2591 		return;
2592 	} else if (unlikely(err_mask)) {
2593 		/* FIXME: not quite right; we don't want the
2594 		 * translation of taskfile registers into
2595 		 * a sense descriptors, since that's only
2596 		 * correct for ATA, not ATAPI
2597 		 */
2598 		ata_gen_passthru_sense(qc);
2599 	} else {
2600 		u8 *scsicmd = cmd->cmnd;
2601 
2602 		if ((scsicmd[0] == INQUIRY) && ((scsicmd[1] & 0x03) == 0)) {
2603 			unsigned long flags;
2604 			u8 *buf;
2605 
2606 			buf = ata_scsi_rbuf_get(cmd, true, &flags);
2607 
2608 	/* ATAPI devices typically report zero for their SCSI version,
2609 	 * and sometimes deviate from the spec WRT response data
2610 	 * format.  If SCSI version is reported as zero like normal,
2611 	 * then we make the following fixups:  1) Fake MMC-5 version,
2612 	 * to indicate to the Linux scsi midlayer this is a modern
2613 	 * device.  2) Ensure response data format / ATAPI information
2614 	 * are always correct.
2615 	 */
2616 			if (buf[2] == 0) {
2617 				buf[2] = 0x5;
2618 				buf[3] = 0x32;
2619 			}
2620 
2621 			ata_scsi_rbuf_put(cmd, true, &flags);
2622 		}
2623 
2624 		cmd->result = SAM_STAT_GOOD;
2625 	}
2626 
2627 	qc->scsidone(cmd);
2628 	ata_qc_free(qc);
2629 }
2630 /**
2631  *	atapi_xlat - Initialize PACKET taskfile
2632  *	@qc: command structure to be initialized
2633  *
2634  *	LOCKING:
2635  *	spin_lock_irqsave(host lock)
2636  *
2637  *	RETURNS:
2638  *	Zero on success, non-zero on failure.
2639  */
2640 static unsigned int atapi_xlat(struct ata_queued_cmd *qc)
2641 {
2642 	struct scsi_cmnd *scmd = qc->scsicmd;
2643 	struct ata_device *dev = qc->dev;
2644 	int nodata = (scmd->sc_data_direction == DMA_NONE);
2645 	int using_pio = !nodata && (dev->flags & ATA_DFLAG_PIO);
2646 	unsigned int nbytes;
2647 
2648 	memset(qc->cdb, 0, dev->cdb_len);
2649 	memcpy(qc->cdb, scmd->cmnd, scmd->cmd_len);
2650 
2651 	qc->complete_fn = atapi_qc_complete;
2652 
2653 	qc->tf.flags |= ATA_TFLAG_ISADDR | ATA_TFLAG_DEVICE;
2654 	if (scmd->sc_data_direction == DMA_TO_DEVICE) {
2655 		qc->tf.flags |= ATA_TFLAG_WRITE;
2656 		DPRINTK("direction: write\n");
2657 	}
2658 
2659 	qc->tf.command = ATA_CMD_PACKET;
2660 	ata_qc_set_pc_nbytes(qc);
2661 
2662 	/* check whether ATAPI DMA is safe */
2663 	if (!nodata && !using_pio && atapi_check_dma(qc))
2664 		using_pio = 1;
2665 
2666 	/* Some controller variants snoop this value for Packet
2667 	 * transfers to do state machine and FIFO management.  Thus we
2668 	 * want to set it properly, and for DMA where it is
2669 	 * effectively meaningless.
2670 	 */
2671 	nbytes = min(ata_qc_raw_nbytes(qc), (unsigned int)63 * 1024);
2672 
2673 	/* Most ATAPI devices which honor transfer chunk size don't
2674 	 * behave according to the spec when odd chunk size which
2675 	 * matches the transfer length is specified.  If the number of
2676 	 * bytes to transfer is 2n+1.  According to the spec, what
2677 	 * should happen is to indicate that 2n+1 is going to be
2678 	 * transferred and transfer 2n+2 bytes where the last byte is
2679 	 * padding.
2680 	 *
2681 	 * In practice, this doesn't happen.  ATAPI devices first
2682 	 * indicate and transfer 2n bytes and then indicate and
2683 	 * transfer 2 bytes where the last byte is padding.
2684 	 *
2685 	 * This inconsistency confuses several controllers which
2686 	 * perform PIO using DMA such as Intel AHCIs and sil3124/32.
2687 	 * These controllers use actual number of transferred bytes to
2688 	 * update DMA poitner and transfer of 4n+2 bytes make those
2689 	 * controller push DMA pointer by 4n+4 bytes because SATA data
2690 	 * FISes are aligned to 4 bytes.  This causes data corruption
2691 	 * and buffer overrun.
2692 	 *
2693 	 * Always setting nbytes to even number solves this problem
2694 	 * because then ATAPI devices don't have to split data at 2n
2695 	 * boundaries.
2696 	 */
2697 	if (nbytes & 0x1)
2698 		nbytes++;
2699 
2700 	qc->tf.lbam = (nbytes & 0xFF);
2701 	qc->tf.lbah = (nbytes >> 8);
2702 
2703 	if (nodata)
2704 		qc->tf.protocol = ATAPI_PROT_NODATA;
2705 	else if (using_pio)
2706 		qc->tf.protocol = ATAPI_PROT_PIO;
2707 	else {
2708 		/* DMA data xfer */
2709 		qc->tf.protocol = ATAPI_PROT_DMA;
2710 		qc->tf.feature |= ATAPI_PKT_DMA;
2711 
2712 		if ((dev->flags & ATA_DFLAG_DMADIR) &&
2713 		    (scmd->sc_data_direction != DMA_TO_DEVICE))
2714 			/* some SATA bridges need us to indicate data xfer direction */
2715 			qc->tf.feature |= ATAPI_DMADIR;
2716 	}
2717 
2718 
2719 	/* FIXME: We need to translate 0x05 READ_BLOCK_LIMITS to a MODE_SENSE
2720 	   as ATAPI tape drives don't get this right otherwise */
2721 	return 0;
2722 }
2723 
2724 static struct ata_device *ata_find_dev(struct ata_port *ap, int devno)
2725 {
2726 	if (!sata_pmp_attached(ap)) {
2727 		if (likely(devno < ata_link_max_devices(&ap->link)))
2728 			return &ap->link.device[devno];
2729 	} else {
2730 		if (likely(devno < ap->nr_pmp_links))
2731 			return &ap->pmp_link[devno].device[0];
2732 	}
2733 
2734 	return NULL;
2735 }
2736 
2737 static struct ata_device *__ata_scsi_find_dev(struct ata_port *ap,
2738 					      const struct scsi_device *scsidev)
2739 {
2740 	int devno;
2741 
2742 	/* skip commands not addressed to targets we simulate */
2743 	if (!sata_pmp_attached(ap)) {
2744 		if (unlikely(scsidev->channel || scsidev->lun))
2745 			return NULL;
2746 		devno = scsidev->id;
2747 	} else {
2748 		if (unlikely(scsidev->id || scsidev->lun))
2749 			return NULL;
2750 		devno = scsidev->channel;
2751 	}
2752 
2753 	return ata_find_dev(ap, devno);
2754 }
2755 
2756 /**
2757  *	ata_scsi_find_dev - lookup ata_device from scsi_cmnd
2758  *	@ap: ATA port to which the device is attached
2759  *	@scsidev: SCSI device from which we derive the ATA device
2760  *
2761  *	Given various information provided in struct scsi_cmnd,
2762  *	map that onto an ATA bus, and using that mapping
2763  *	determine which ata_device is associated with the
2764  *	SCSI command to be sent.
2765  *
2766  *	LOCKING:
2767  *	spin_lock_irqsave(host lock)
2768  *
2769  *	RETURNS:
2770  *	Associated ATA device, or %NULL if not found.
2771  */
2772 static struct ata_device *
2773 ata_scsi_find_dev(struct ata_port *ap, const struct scsi_device *scsidev)
2774 {
2775 	struct ata_device *dev = __ata_scsi_find_dev(ap, scsidev);
2776 
2777 	if (unlikely(!dev || !ata_dev_enabled(dev)))
2778 		return NULL;
2779 
2780 	return dev;
2781 }
2782 
2783 /*
2784  *	ata_scsi_map_proto - Map pass-thru protocol value to taskfile value.
2785  *	@byte1: Byte 1 from pass-thru CDB.
2786  *
2787  *	RETURNS:
2788  *	ATA_PROT_UNKNOWN if mapping failed/unimplemented, protocol otherwise.
2789  */
2790 static u8
2791 ata_scsi_map_proto(u8 byte1)
2792 {
2793 	switch((byte1 & 0x1e) >> 1) {
2794 	case 3:		/* Non-data */
2795 		return ATA_PROT_NODATA;
2796 
2797 	case 6:		/* DMA */
2798 	case 10:	/* UDMA Data-in */
2799 	case 11:	/* UDMA Data-Out */
2800 		return ATA_PROT_DMA;
2801 
2802 	case 4:		/* PIO Data-in */
2803 	case 5:		/* PIO Data-out */
2804 		return ATA_PROT_PIO;
2805 
2806 	case 0:		/* Hard Reset */
2807 	case 1:		/* SRST */
2808 	case 8:		/* Device Diagnostic */
2809 	case 9:		/* Device Reset */
2810 	case 7:		/* DMA Queued */
2811 	case 12:	/* FPDMA */
2812 	case 15:	/* Return Response Info */
2813 	default:	/* Reserved */
2814 		break;
2815 	}
2816 
2817 	return ATA_PROT_UNKNOWN;
2818 }
2819 
2820 /**
2821  *	ata_scsi_pass_thru - convert ATA pass-thru CDB to taskfile
2822  *	@qc: command structure to be initialized
2823  *
2824  *	Handles either 12 or 16-byte versions of the CDB.
2825  *
2826  *	RETURNS:
2827  *	Zero on success, non-zero on failure.
2828  */
2829 static unsigned int ata_scsi_pass_thru(struct ata_queued_cmd *qc)
2830 {
2831 	struct ata_taskfile *tf = &(qc->tf);
2832 	struct scsi_cmnd *scmd = qc->scsicmd;
2833 	struct ata_device *dev = qc->dev;
2834 	const u8 *cdb = scmd->cmnd;
2835 
2836 	if ((tf->protocol = ata_scsi_map_proto(cdb[1])) == ATA_PROT_UNKNOWN)
2837 		goto invalid_fld;
2838 
2839 	/*
2840 	 * 12 and 16 byte CDBs use different offsets to
2841 	 * provide the various register values.
2842 	 */
2843 	if (cdb[0] == ATA_16) {
2844 		/*
2845 		 * 16-byte CDB - may contain extended commands.
2846 		 *
2847 		 * If that is the case, copy the upper byte register values.
2848 		 */
2849 		if (cdb[1] & 0x01) {
2850 			tf->hob_feature = cdb[3];
2851 			tf->hob_nsect = cdb[5];
2852 			tf->hob_lbal = cdb[7];
2853 			tf->hob_lbam = cdb[9];
2854 			tf->hob_lbah = cdb[11];
2855 			tf->flags |= ATA_TFLAG_LBA48;
2856 		} else
2857 			tf->flags &= ~ATA_TFLAG_LBA48;
2858 
2859 		/*
2860 		 * Always copy low byte, device and command registers.
2861 		 */
2862 		tf->feature = cdb[4];
2863 		tf->nsect = cdb[6];
2864 		tf->lbal = cdb[8];
2865 		tf->lbam = cdb[10];
2866 		tf->lbah = cdb[12];
2867 		tf->device = cdb[13];
2868 		tf->command = cdb[14];
2869 	} else {
2870 		/*
2871 		 * 12-byte CDB - incapable of extended commands.
2872 		 */
2873 		tf->flags &= ~ATA_TFLAG_LBA48;
2874 
2875 		tf->feature = cdb[3];
2876 		tf->nsect = cdb[4];
2877 		tf->lbal = cdb[5];
2878 		tf->lbam = cdb[6];
2879 		tf->lbah = cdb[7];
2880 		tf->device = cdb[8];
2881 		tf->command = cdb[9];
2882 	}
2883 
2884 	/* enforce correct master/slave bit */
2885 	tf->device = dev->devno ?
2886 		tf->device | ATA_DEV1 : tf->device & ~ATA_DEV1;
2887 
2888 	switch (tf->command) {
2889 	/* READ/WRITE LONG use a non-standard sect_size */
2890 	case ATA_CMD_READ_LONG:
2891 	case ATA_CMD_READ_LONG_ONCE:
2892 	case ATA_CMD_WRITE_LONG:
2893 	case ATA_CMD_WRITE_LONG_ONCE:
2894 		if (tf->protocol != ATA_PROT_PIO || tf->nsect != 1)
2895 			goto invalid_fld;
2896 		qc->sect_size = scsi_bufflen(scmd);
2897 		break;
2898 
2899 	/* commands using reported Logical Block size (e.g. 512 or 4K) */
2900 	case ATA_CMD_CFA_WRITE_NE:
2901 	case ATA_CMD_CFA_TRANS_SECT:
2902 	case ATA_CMD_CFA_WRITE_MULT_NE:
2903 	/* XXX: case ATA_CMD_CFA_WRITE_SECTORS_WITHOUT_ERASE: */
2904 	case ATA_CMD_READ:
2905 	case ATA_CMD_READ_EXT:
2906 	case ATA_CMD_READ_QUEUED:
2907 	/* XXX: case ATA_CMD_READ_QUEUED_EXT: */
2908 	case ATA_CMD_FPDMA_READ:
2909 	case ATA_CMD_READ_MULTI:
2910 	case ATA_CMD_READ_MULTI_EXT:
2911 	case ATA_CMD_PIO_READ:
2912 	case ATA_CMD_PIO_READ_EXT:
2913 	case ATA_CMD_READ_STREAM_DMA_EXT:
2914 	case ATA_CMD_READ_STREAM_EXT:
2915 	case ATA_CMD_VERIFY:
2916 	case ATA_CMD_VERIFY_EXT:
2917 	case ATA_CMD_WRITE:
2918 	case ATA_CMD_WRITE_EXT:
2919 	case ATA_CMD_WRITE_FUA_EXT:
2920 	case ATA_CMD_WRITE_QUEUED:
2921 	case ATA_CMD_WRITE_QUEUED_FUA_EXT:
2922 	case ATA_CMD_FPDMA_WRITE:
2923 	case ATA_CMD_WRITE_MULTI:
2924 	case ATA_CMD_WRITE_MULTI_EXT:
2925 	case ATA_CMD_WRITE_MULTI_FUA_EXT:
2926 	case ATA_CMD_PIO_WRITE:
2927 	case ATA_CMD_PIO_WRITE_EXT:
2928 	case ATA_CMD_WRITE_STREAM_DMA_EXT:
2929 	case ATA_CMD_WRITE_STREAM_EXT:
2930 		qc->sect_size = scmd->device->sector_size;
2931 		break;
2932 
2933 	/* Everything else uses 512 byte "sectors" */
2934 	default:
2935 		qc->sect_size = ATA_SECT_SIZE;
2936 	}
2937 
2938 	/*
2939 	 * Set flags so that all registers will be written, pass on
2940 	 * write indication (used for PIO/DMA setup), result TF is
2941 	 * copied back and we don't whine too much about its failure.
2942 	 */
2943 	tf->flags |= ATA_TFLAG_ISADDR | ATA_TFLAG_DEVICE;
2944 	if (scmd->sc_data_direction == DMA_TO_DEVICE)
2945 		tf->flags |= ATA_TFLAG_WRITE;
2946 
2947 	qc->flags |= ATA_QCFLAG_RESULT_TF | ATA_QCFLAG_QUIET;
2948 
2949 	/*
2950 	 * Set transfer length.
2951 	 *
2952 	 * TODO: find out if we need to do more here to
2953 	 *       cover scatter/gather case.
2954 	 */
2955 	ata_qc_set_pc_nbytes(qc);
2956 
2957 	/* We may not issue DMA commands if no DMA mode is set */
2958 	if (tf->protocol == ATA_PROT_DMA && dev->dma_mode == 0)
2959 		goto invalid_fld;
2960 
2961 	/* sanity check for pio multi commands */
2962 	if ((cdb[1] & 0xe0) && !is_multi_taskfile(tf))
2963 		goto invalid_fld;
2964 
2965 	if (is_multi_taskfile(tf)) {
2966 		unsigned int multi_count = 1 << (cdb[1] >> 5);
2967 
2968 		/* compare the passed through multi_count
2969 		 * with the cached multi_count of libata
2970 		 */
2971 		if (multi_count != dev->multi_count)
2972 			ata_dev_printk(dev, KERN_WARNING,
2973 				       "invalid multi_count %u ignored\n",
2974 				       multi_count);
2975 	}
2976 
2977 	/*
2978 	 * Filter SET_FEATURES - XFER MODE command -- otherwise,
2979 	 * SET_FEATURES - XFER MODE must be preceded/succeeded
2980 	 * by an update to hardware-specific registers for each
2981 	 * controller (i.e. the reason for ->set_piomode(),
2982 	 * ->set_dmamode(), and ->post_set_mode() hooks).
2983 	 */
2984 	if (tf->command == ATA_CMD_SET_FEATURES &&
2985 	    tf->feature == SETFEATURES_XFER)
2986 		goto invalid_fld;
2987 
2988 	/*
2989 	 * Filter TPM commands by default. These provide an
2990 	 * essentially uncontrolled encrypted "back door" between
2991 	 * applications and the disk. Set libata.allow_tpm=1 if you
2992 	 * have a real reason for wanting to use them. This ensures
2993 	 * that installed software cannot easily mess stuff up without
2994 	 * user intent. DVR type users will probably ship with this enabled
2995 	 * for movie content management.
2996 	 *
2997 	 * Note that for ATA8 we can issue a DCS change and DCS freeze lock
2998 	 * for this and should do in future but that it is not sufficient as
2999 	 * DCS is an optional feature set. Thus we also do the software filter
3000 	 * so that we comply with the TC consortium stated goal that the user
3001 	 * can turn off TC features of their system.
3002 	 */
3003 	if (tf->command >= 0x5C && tf->command <= 0x5F && !libata_allow_tpm)
3004 		goto invalid_fld;
3005 
3006 	return 0;
3007 
3008  invalid_fld:
3009 	ata_scsi_set_sense(scmd, ILLEGAL_REQUEST, 0x24, 0x00);
3010 	/* "Invalid field in cdb" */
3011 	return 1;
3012 }
3013 
3014 static unsigned int ata_scsi_write_same_xlat(struct ata_queued_cmd *qc)
3015 {
3016 	struct ata_taskfile *tf = &qc->tf;
3017 	struct scsi_cmnd *scmd = qc->scsicmd;
3018 	struct ata_device *dev = qc->dev;
3019 	const u8 *cdb = scmd->cmnd;
3020 	u64 block;
3021 	u32 n_block;
3022 	u32 size;
3023 	void *buf;
3024 
3025 	/* we may not issue DMA commands if no DMA mode is set */
3026 	if (unlikely(!dev->dma_mode))
3027 		goto invalid_fld;
3028 
3029 	if (unlikely(scmd->cmd_len < 16))
3030 		goto invalid_fld;
3031 	scsi_16_lba_len(cdb, &block, &n_block);
3032 
3033 	/* for now we only support WRITE SAME with the unmap bit set */
3034 	if (unlikely(!(cdb[1] & 0x8)))
3035 		goto invalid_fld;
3036 
3037 	/*
3038 	 * WRITE SAME always has a sector sized buffer as payload, this
3039 	 * should never be a multiple entry S/G list.
3040 	 */
3041 	if (!scsi_sg_count(scmd))
3042 		goto invalid_fld;
3043 
3044 	buf = page_address(sg_page(scsi_sglist(scmd)));
3045 	size = ata_set_lba_range_entries(buf, 512, block, n_block);
3046 
3047 	tf->protocol = ATA_PROT_DMA;
3048 	tf->hob_feature = 0;
3049 	tf->feature = ATA_DSM_TRIM;
3050 	tf->hob_nsect = (size / 512) >> 8;
3051 	tf->nsect = size / 512;
3052 	tf->command = ATA_CMD_DSM;
3053 	tf->flags |= ATA_TFLAG_ISADDR | ATA_TFLAG_DEVICE | ATA_TFLAG_LBA48 |
3054 		     ATA_TFLAG_WRITE;
3055 
3056 	ata_qc_set_pc_nbytes(qc);
3057 
3058 	return 0;
3059 
3060  invalid_fld:
3061 	ata_scsi_set_sense(scmd, ILLEGAL_REQUEST, 0x24, 0x00);
3062 	/* "Invalid field in cdb" */
3063 	return 1;
3064 }
3065 
3066 /**
3067  *	ata_get_xlat_func - check if SCSI to ATA translation is possible
3068  *	@dev: ATA device
3069  *	@cmd: SCSI command opcode to consider
3070  *
3071  *	Look up the SCSI command given, and determine whether the
3072  *	SCSI command is to be translated or simulated.
3073  *
3074  *	RETURNS:
3075  *	Pointer to translation function if possible, %NULL if not.
3076  */
3077 
3078 static inline ata_xlat_func_t ata_get_xlat_func(struct ata_device *dev, u8 cmd)
3079 {
3080 	switch (cmd) {
3081 	case READ_6:
3082 	case READ_10:
3083 	case READ_16:
3084 
3085 	case WRITE_6:
3086 	case WRITE_10:
3087 	case WRITE_16:
3088 		return ata_scsi_rw_xlat;
3089 
3090 	case WRITE_SAME_16:
3091 		return ata_scsi_write_same_xlat;
3092 
3093 	case SYNCHRONIZE_CACHE:
3094 		if (ata_try_flush_cache(dev))
3095 			return ata_scsi_flush_xlat;
3096 		break;
3097 
3098 	case VERIFY:
3099 	case VERIFY_16:
3100 		return ata_scsi_verify_xlat;
3101 
3102 	case ATA_12:
3103 	case ATA_16:
3104 		return ata_scsi_pass_thru;
3105 
3106 	case START_STOP:
3107 		return ata_scsi_start_stop_xlat;
3108 	}
3109 
3110 	return NULL;
3111 }
3112 
3113 /**
3114  *	ata_scsi_dump_cdb - dump SCSI command contents to dmesg
3115  *	@ap: ATA port to which the command was being sent
3116  *	@cmd: SCSI command to dump
3117  *
3118  *	Prints the contents of a SCSI command via printk().
3119  */
3120 
3121 static inline void ata_scsi_dump_cdb(struct ata_port *ap,
3122 				     struct scsi_cmnd *cmd)
3123 {
3124 #ifdef ATA_DEBUG
3125 	struct scsi_device *scsidev = cmd->device;
3126 	u8 *scsicmd = cmd->cmnd;
3127 
3128 	DPRINTK("CDB (%u:%d,%d,%d) %02x %02x %02x %02x %02x %02x %02x %02x %02x\n",
3129 		ap->print_id,
3130 		scsidev->channel, scsidev->id, scsidev->lun,
3131 		scsicmd[0], scsicmd[1], scsicmd[2], scsicmd[3],
3132 		scsicmd[4], scsicmd[5], scsicmd[6], scsicmd[7],
3133 		scsicmd[8]);
3134 #endif
3135 }
3136 
3137 static inline int __ata_scsi_queuecmd(struct scsi_cmnd *scmd,
3138 				      struct ata_device *dev)
3139 {
3140 	u8 scsi_op = scmd->cmnd[0];
3141 	ata_xlat_func_t xlat_func;
3142 	int rc = 0;
3143 
3144 	if (dev->class == ATA_DEV_ATA) {
3145 		if (unlikely(!scmd->cmd_len || scmd->cmd_len > dev->cdb_len))
3146 			goto bad_cdb_len;
3147 
3148 		xlat_func = ata_get_xlat_func(dev, scsi_op);
3149 	} else {
3150 		if (unlikely(!scmd->cmd_len))
3151 			goto bad_cdb_len;
3152 
3153 		xlat_func = NULL;
3154 		if (likely((scsi_op != ATA_16) || !atapi_passthru16)) {
3155 			/* relay SCSI command to ATAPI device */
3156 			int len = COMMAND_SIZE(scsi_op);
3157 			if (unlikely(len > scmd->cmd_len || len > dev->cdb_len))
3158 				goto bad_cdb_len;
3159 
3160 			xlat_func = atapi_xlat;
3161 		} else {
3162 			/* ATA_16 passthru, treat as an ATA command */
3163 			if (unlikely(scmd->cmd_len > 16))
3164 				goto bad_cdb_len;
3165 
3166 			xlat_func = ata_get_xlat_func(dev, scsi_op);
3167 		}
3168 	}
3169 
3170 	if (xlat_func)
3171 		rc = ata_scsi_translate(dev, scmd, xlat_func);
3172 	else
3173 		ata_scsi_simulate(dev, scmd);
3174 
3175 	return rc;
3176 
3177  bad_cdb_len:
3178 	DPRINTK("bad CDB len=%u, scsi_op=0x%02x, max=%u\n",
3179 		scmd->cmd_len, scsi_op, dev->cdb_len);
3180 	scmd->result = DID_ERROR << 16;
3181 	scmd->scsi_done(scmd);
3182 	return 0;
3183 }
3184 
3185 /**
3186  *	ata_scsi_queuecmd - Issue SCSI cdb to libata-managed device
3187  *	@shost: SCSI host of command to be sent
3188  *	@cmd: SCSI command to be sent
3189  *
3190  *	In some cases, this function translates SCSI commands into
3191  *	ATA taskfiles, and queues the taskfiles to be sent to
3192  *	hardware.  In other cases, this function simulates a
3193  *	SCSI device by evaluating and responding to certain
3194  *	SCSI commands.  This creates the overall effect of
3195  *	ATA and ATAPI devices appearing as SCSI devices.
3196  *
3197  *	LOCKING:
3198  *	ATA host lock
3199  *
3200  *	RETURNS:
3201  *	Return value from __ata_scsi_queuecmd() if @cmd can be queued,
3202  *	0 otherwise.
3203  */
3204 int ata_scsi_queuecmd(struct Scsi_Host *shost, struct scsi_cmnd *cmd)
3205 {
3206 	struct ata_port *ap;
3207 	struct ata_device *dev;
3208 	struct scsi_device *scsidev = cmd->device;
3209 	int rc = 0;
3210 	unsigned long irq_flags;
3211 
3212 	ap = ata_shost_to_port(shost);
3213 
3214 	spin_lock_irqsave(ap->lock, irq_flags);
3215 
3216 	ata_scsi_dump_cdb(ap, cmd);
3217 
3218 	dev = ata_scsi_find_dev(ap, scsidev);
3219 	if (likely(dev))
3220 		rc = __ata_scsi_queuecmd(cmd, dev);
3221 	else {
3222 		cmd->result = (DID_BAD_TARGET << 16);
3223 		cmd->scsi_done(cmd);
3224 	}
3225 
3226 	spin_unlock_irqrestore(ap->lock, irq_flags);
3227 
3228 	return rc;
3229 }
3230 
3231 /**
3232  *	ata_scsi_simulate - simulate SCSI command on ATA device
3233  *	@dev: the target device
3234  *	@cmd: SCSI command being sent to device.
3235  *
3236  *	Interprets and directly executes a select list of SCSI commands
3237  *	that can be handled internally.
3238  *
3239  *	LOCKING:
3240  *	spin_lock_irqsave(host lock)
3241  */
3242 
3243 void ata_scsi_simulate(struct ata_device *dev, struct scsi_cmnd *cmd)
3244 {
3245 	struct ata_scsi_args args;
3246 	const u8 *scsicmd = cmd->cmnd;
3247 	u8 tmp8;
3248 
3249 	args.dev = dev;
3250 	args.id = dev->id;
3251 	args.cmd = cmd;
3252 	args.done = cmd->scsi_done;
3253 
3254 	switch(scsicmd[0]) {
3255 	/* TODO: worth improving? */
3256 	case FORMAT_UNIT:
3257 		ata_scsi_invalid_field(cmd);
3258 		break;
3259 
3260 	case INQUIRY:
3261 		if (scsicmd[1] & 2)	           /* is CmdDt set?  */
3262 			ata_scsi_invalid_field(cmd);
3263 		else if ((scsicmd[1] & 1) == 0)    /* is EVPD clear? */
3264 			ata_scsi_rbuf_fill(&args, ata_scsiop_inq_std);
3265 		else switch (scsicmd[2]) {
3266 		case 0x00:
3267 			ata_scsi_rbuf_fill(&args, ata_scsiop_inq_00);
3268 			break;
3269 		case 0x80:
3270 			ata_scsi_rbuf_fill(&args, ata_scsiop_inq_80);
3271 			break;
3272 		case 0x83:
3273 			ata_scsi_rbuf_fill(&args, ata_scsiop_inq_83);
3274 			break;
3275 		case 0x89:
3276 			ata_scsi_rbuf_fill(&args, ata_scsiop_inq_89);
3277 			break;
3278 		case 0xb0:
3279 			ata_scsi_rbuf_fill(&args, ata_scsiop_inq_b0);
3280 			break;
3281 		case 0xb1:
3282 			ata_scsi_rbuf_fill(&args, ata_scsiop_inq_b1);
3283 			break;
3284 		case 0xb2:
3285 			ata_scsi_rbuf_fill(&args, ata_scsiop_inq_b2);
3286 			break;
3287 		default:
3288 			ata_scsi_invalid_field(cmd);
3289 			break;
3290 		}
3291 		break;
3292 
3293 	case MODE_SENSE:
3294 	case MODE_SENSE_10:
3295 		ata_scsi_rbuf_fill(&args, ata_scsiop_mode_sense);
3296 		break;
3297 
3298 	case MODE_SELECT:	/* unconditionally return */
3299 	case MODE_SELECT_10:	/* bad-field-in-cdb */
3300 		ata_scsi_invalid_field(cmd);
3301 		break;
3302 
3303 	case READ_CAPACITY:
3304 		ata_scsi_rbuf_fill(&args, ata_scsiop_read_cap);
3305 		break;
3306 
3307 	case SERVICE_ACTION_IN:
3308 		if ((scsicmd[1] & 0x1f) == SAI_READ_CAPACITY_16)
3309 			ata_scsi_rbuf_fill(&args, ata_scsiop_read_cap);
3310 		else
3311 			ata_scsi_invalid_field(cmd);
3312 		break;
3313 
3314 	case REPORT_LUNS:
3315 		ata_scsi_rbuf_fill(&args, ata_scsiop_report_luns);
3316 		break;
3317 
3318 	case REQUEST_SENSE:
3319 		ata_scsi_set_sense(cmd, 0, 0, 0);
3320 		cmd->result = (DRIVER_SENSE << 24);
3321 		cmd->scsi_done(cmd);
3322 		break;
3323 
3324 	/* if we reach this, then writeback caching is disabled,
3325 	 * turning this into a no-op.
3326 	 */
3327 	case SYNCHRONIZE_CACHE:
3328 		/* fall through */
3329 
3330 	/* no-op's, complete with success */
3331 	case REZERO_UNIT:
3332 	case SEEK_6:
3333 	case SEEK_10:
3334 	case TEST_UNIT_READY:
3335 		ata_scsi_rbuf_fill(&args, ata_scsiop_noop);
3336 		break;
3337 
3338 	case SEND_DIAGNOSTIC:
3339 		tmp8 = scsicmd[1] & ~(1 << 3);
3340 		if ((tmp8 == 0x4) && (!scsicmd[3]) && (!scsicmd[4]))
3341 			ata_scsi_rbuf_fill(&args, ata_scsiop_noop);
3342 		else
3343 			ata_scsi_invalid_field(cmd);
3344 		break;
3345 
3346 	/* all other commands */
3347 	default:
3348 		ata_scsi_set_sense(cmd, ILLEGAL_REQUEST, 0x20, 0x0);
3349 		/* "Invalid command operation code" */
3350 		cmd->scsi_done(cmd);
3351 		break;
3352 	}
3353 }
3354 
3355 int ata_scsi_add_hosts(struct ata_host *host, struct scsi_host_template *sht)
3356 {
3357 	int i, rc;
3358 
3359 	for (i = 0; i < host->n_ports; i++) {
3360 		struct ata_port *ap = host->ports[i];
3361 		struct Scsi_Host *shost;
3362 
3363 		rc = -ENOMEM;
3364 		shost = scsi_host_alloc(sht, sizeof(struct ata_port *));
3365 		if (!shost)
3366 			goto err_alloc;
3367 
3368 		*(struct ata_port **)&shost->hostdata[0] = ap;
3369 		ap->scsi_host = shost;
3370 
3371 		shost->transportt = ata_scsi_transport_template;
3372 		shost->unique_id = ap->print_id;
3373 		shost->max_id = 16;
3374 		shost->max_lun = 1;
3375 		shost->max_channel = 1;
3376 		shost->max_cmd_len = 16;
3377 
3378 		/* Schedule policy is determined by ->qc_defer()
3379 		 * callback and it needs to see every deferred qc.
3380 		 * Set host_blocked to 1 to prevent SCSI midlayer from
3381 		 * automatically deferring requests.
3382 		 */
3383 		shost->max_host_blocked = 1;
3384 
3385 		rc = scsi_add_host(ap->scsi_host, ap->host->dev);
3386 		if (rc)
3387 			goto err_add;
3388 	}
3389 
3390 	return 0;
3391 
3392  err_add:
3393 	scsi_host_put(host->ports[i]->scsi_host);
3394  err_alloc:
3395 	while (--i >= 0) {
3396 		struct Scsi_Host *shost = host->ports[i]->scsi_host;
3397 
3398 		scsi_remove_host(shost);
3399 		scsi_host_put(shost);
3400 	}
3401 	return rc;
3402 }
3403 
3404 void ata_scsi_scan_host(struct ata_port *ap, int sync)
3405 {
3406 	int tries = 5;
3407 	struct ata_device *last_failed_dev = NULL;
3408 	struct ata_link *link;
3409 	struct ata_device *dev;
3410 
3411  repeat:
3412 	ata_for_each_link(link, ap, EDGE) {
3413 		ata_for_each_dev(dev, link, ENABLED) {
3414 			struct scsi_device *sdev;
3415 			int channel = 0, id = 0;
3416 
3417 			if (dev->sdev)
3418 				continue;
3419 
3420 			if (ata_is_host_link(link))
3421 				id = dev->devno;
3422 			else
3423 				channel = link->pmp;
3424 
3425 			sdev = __scsi_add_device(ap->scsi_host, channel, id, 0,
3426 						 NULL);
3427 			if (!IS_ERR(sdev)) {
3428 				dev->sdev = sdev;
3429 				scsi_device_put(sdev);
3430 			} else {
3431 				dev->sdev = NULL;
3432 			}
3433 		}
3434 	}
3435 
3436 	/* If we scanned while EH was in progress or allocation
3437 	 * failure occurred, scan would have failed silently.  Check
3438 	 * whether all devices are attached.
3439 	 */
3440 	ata_for_each_link(link, ap, EDGE) {
3441 		ata_for_each_dev(dev, link, ENABLED) {
3442 			if (!dev->sdev)
3443 				goto exit_loop;
3444 		}
3445 	}
3446  exit_loop:
3447 	if (!link)
3448 		return;
3449 
3450 	/* we're missing some SCSI devices */
3451 	if (sync) {
3452 		/* If caller requested synchrnous scan && we've made
3453 		 * any progress, sleep briefly and repeat.
3454 		 */
3455 		if (dev != last_failed_dev) {
3456 			msleep(100);
3457 			last_failed_dev = dev;
3458 			goto repeat;
3459 		}
3460 
3461 		/* We might be failing to detect boot device, give it
3462 		 * a few more chances.
3463 		 */
3464 		if (--tries) {
3465 			msleep(100);
3466 			goto repeat;
3467 		}
3468 
3469 		ata_port_printk(ap, KERN_ERR, "WARNING: synchronous SCSI scan "
3470 				"failed without making any progress,\n"
3471 				"                  switching to async\n");
3472 	}
3473 
3474 	queue_delayed_work(system_long_wq, &ap->hotplug_task,
3475 			   round_jiffies_relative(HZ));
3476 }
3477 
3478 /**
3479  *	ata_scsi_offline_dev - offline attached SCSI device
3480  *	@dev: ATA device to offline attached SCSI device for
3481  *
3482  *	This function is called from ata_eh_hotplug() and responsible
3483  *	for taking the SCSI device attached to @dev offline.  This
3484  *	function is called with host lock which protects dev->sdev
3485  *	against clearing.
3486  *
3487  *	LOCKING:
3488  *	spin_lock_irqsave(host lock)
3489  *
3490  *	RETURNS:
3491  *	1 if attached SCSI device exists, 0 otherwise.
3492  */
3493 int ata_scsi_offline_dev(struct ata_device *dev)
3494 {
3495 	if (dev->sdev) {
3496 		scsi_device_set_state(dev->sdev, SDEV_OFFLINE);
3497 		return 1;
3498 	}
3499 	return 0;
3500 }
3501 
3502 /**
3503  *	ata_scsi_remove_dev - remove attached SCSI device
3504  *	@dev: ATA device to remove attached SCSI device for
3505  *
3506  *	This function is called from ata_eh_scsi_hotplug() and
3507  *	responsible for removing the SCSI device attached to @dev.
3508  *
3509  *	LOCKING:
3510  *	Kernel thread context (may sleep).
3511  */
3512 static void ata_scsi_remove_dev(struct ata_device *dev)
3513 {
3514 	struct ata_port *ap = dev->link->ap;
3515 	struct scsi_device *sdev;
3516 	unsigned long flags;
3517 
3518 	/* Alas, we need to grab scan_mutex to ensure SCSI device
3519 	 * state doesn't change underneath us and thus
3520 	 * scsi_device_get() always succeeds.  The mutex locking can
3521 	 * be removed if there is __scsi_device_get() interface which
3522 	 * increments reference counts regardless of device state.
3523 	 */
3524 	mutex_lock(&ap->scsi_host->scan_mutex);
3525 	spin_lock_irqsave(ap->lock, flags);
3526 
3527 	/* clearing dev->sdev is protected by host lock */
3528 	sdev = dev->sdev;
3529 	dev->sdev = NULL;
3530 
3531 	if (sdev) {
3532 		/* If user initiated unplug races with us, sdev can go
3533 		 * away underneath us after the host lock and
3534 		 * scan_mutex are released.  Hold onto it.
3535 		 */
3536 		if (scsi_device_get(sdev) == 0) {
3537 			/* The following ensures the attached sdev is
3538 			 * offline on return from ata_scsi_offline_dev()
3539 			 * regardless it wins or loses the race
3540 			 * against this function.
3541 			 */
3542 			scsi_device_set_state(sdev, SDEV_OFFLINE);
3543 		} else {
3544 			WARN_ON(1);
3545 			sdev = NULL;
3546 		}
3547 	}
3548 
3549 	spin_unlock_irqrestore(ap->lock, flags);
3550 	mutex_unlock(&ap->scsi_host->scan_mutex);
3551 
3552 	if (sdev) {
3553 		ata_dev_printk(dev, KERN_INFO, "detaching (SCSI %s)\n",
3554 			       dev_name(&sdev->sdev_gendev));
3555 
3556 		scsi_remove_device(sdev);
3557 		scsi_device_put(sdev);
3558 	}
3559 }
3560 
3561 static void ata_scsi_handle_link_detach(struct ata_link *link)
3562 {
3563 	struct ata_port *ap = link->ap;
3564 	struct ata_device *dev;
3565 
3566 	ata_for_each_dev(dev, link, ALL) {
3567 		unsigned long flags;
3568 
3569 		if (!(dev->flags & ATA_DFLAG_DETACHED))
3570 			continue;
3571 
3572 		spin_lock_irqsave(ap->lock, flags);
3573 		dev->flags &= ~ATA_DFLAG_DETACHED;
3574 		spin_unlock_irqrestore(ap->lock, flags);
3575 
3576 		ata_scsi_remove_dev(dev);
3577 	}
3578 }
3579 
3580 /**
3581  *	ata_scsi_media_change_notify - send media change event
3582  *	@dev: Pointer to the disk device with media change event
3583  *
3584  *	Tell the block layer to send a media change notification
3585  *	event.
3586  *
3587  * 	LOCKING:
3588  * 	spin_lock_irqsave(host lock)
3589  */
3590 void ata_scsi_media_change_notify(struct ata_device *dev)
3591 {
3592 	if (dev->sdev)
3593 		sdev_evt_send_simple(dev->sdev, SDEV_EVT_MEDIA_CHANGE,
3594 				     GFP_ATOMIC);
3595 }
3596 
3597 /**
3598  *	ata_scsi_hotplug - SCSI part of hotplug
3599  *	@work: Pointer to ATA port to perform SCSI hotplug on
3600  *
3601  *	Perform SCSI part of hotplug.  It's executed from a separate
3602  *	workqueue after EH completes.  This is necessary because SCSI
3603  *	hot plugging requires working EH and hot unplugging is
3604  *	synchronized with hot plugging with a mutex.
3605  *
3606  *	LOCKING:
3607  *	Kernel thread context (may sleep).
3608  */
3609 void ata_scsi_hotplug(struct work_struct *work)
3610 {
3611 	struct ata_port *ap =
3612 		container_of(work, struct ata_port, hotplug_task.work);
3613 	int i;
3614 
3615 	if (ap->pflags & ATA_PFLAG_UNLOADING) {
3616 		DPRINTK("ENTER/EXIT - unloading\n");
3617 		return;
3618 	}
3619 
3620 	DPRINTK("ENTER\n");
3621 	mutex_lock(&ap->scsi_scan_mutex);
3622 
3623 	/* Unplug detached devices.  We cannot use link iterator here
3624 	 * because PMP links have to be scanned even if PMP is
3625 	 * currently not attached.  Iterate manually.
3626 	 */
3627 	ata_scsi_handle_link_detach(&ap->link);
3628 	if (ap->pmp_link)
3629 		for (i = 0; i < SATA_PMP_MAX_PORTS; i++)
3630 			ata_scsi_handle_link_detach(&ap->pmp_link[i]);
3631 
3632 	/* scan for new ones */
3633 	ata_scsi_scan_host(ap, 0);
3634 
3635 	mutex_unlock(&ap->scsi_scan_mutex);
3636 	DPRINTK("EXIT\n");
3637 }
3638 
3639 /**
3640  *	ata_scsi_user_scan - indication for user-initiated bus scan
3641  *	@shost: SCSI host to scan
3642  *	@channel: Channel to scan
3643  *	@id: ID to scan
3644  *	@lun: LUN to scan
3645  *
3646  *	This function is called when user explicitly requests bus
3647  *	scan.  Set probe pending flag and invoke EH.
3648  *
3649  *	LOCKING:
3650  *	SCSI layer (we don't care)
3651  *
3652  *	RETURNS:
3653  *	Zero.
3654  */
3655 int ata_scsi_user_scan(struct Scsi_Host *shost, unsigned int channel,
3656 		       unsigned int id, unsigned int lun)
3657 {
3658 	struct ata_port *ap = ata_shost_to_port(shost);
3659 	unsigned long flags;
3660 	int devno, rc = 0;
3661 
3662 	if (!ap->ops->error_handler)
3663 		return -EOPNOTSUPP;
3664 
3665 	if (lun != SCAN_WILD_CARD && lun)
3666 		return -EINVAL;
3667 
3668 	if (!sata_pmp_attached(ap)) {
3669 		if (channel != SCAN_WILD_CARD && channel)
3670 			return -EINVAL;
3671 		devno = id;
3672 	} else {
3673 		if (id != SCAN_WILD_CARD && id)
3674 			return -EINVAL;
3675 		devno = channel;
3676 	}
3677 
3678 	spin_lock_irqsave(ap->lock, flags);
3679 
3680 	if (devno == SCAN_WILD_CARD) {
3681 		struct ata_link *link;
3682 
3683 		ata_for_each_link(link, ap, EDGE) {
3684 			struct ata_eh_info *ehi = &link->eh_info;
3685 			ehi->probe_mask |= ATA_ALL_DEVICES;
3686 			ehi->action |= ATA_EH_RESET;
3687 		}
3688 	} else {
3689 		struct ata_device *dev = ata_find_dev(ap, devno);
3690 
3691 		if (dev) {
3692 			struct ata_eh_info *ehi = &dev->link->eh_info;
3693 			ehi->probe_mask |= 1 << dev->devno;
3694 			ehi->action |= ATA_EH_RESET;
3695 		} else
3696 			rc = -EINVAL;
3697 	}
3698 
3699 	if (rc == 0) {
3700 		ata_port_schedule_eh(ap);
3701 		spin_unlock_irqrestore(ap->lock, flags);
3702 		ata_port_wait_eh(ap);
3703 	} else
3704 		spin_unlock_irqrestore(ap->lock, flags);
3705 
3706 	return rc;
3707 }
3708 
3709 /**
3710  *	ata_scsi_dev_rescan - initiate scsi_rescan_device()
3711  *	@work: Pointer to ATA port to perform scsi_rescan_device()
3712  *
3713  *	After ATA pass thru (SAT) commands are executed successfully,
3714  *	libata need to propagate the changes to SCSI layer.
3715  *
3716  *	LOCKING:
3717  *	Kernel thread context (may sleep).
3718  */
3719 void ata_scsi_dev_rescan(struct work_struct *work)
3720 {
3721 	struct ata_port *ap =
3722 		container_of(work, struct ata_port, scsi_rescan_task);
3723 	struct ata_link *link;
3724 	struct ata_device *dev;
3725 	unsigned long flags;
3726 
3727 	mutex_lock(&ap->scsi_scan_mutex);
3728 	spin_lock_irqsave(ap->lock, flags);
3729 
3730 	ata_for_each_link(link, ap, EDGE) {
3731 		ata_for_each_dev(dev, link, ENABLED) {
3732 			struct scsi_device *sdev = dev->sdev;
3733 
3734 			if (!sdev)
3735 				continue;
3736 			if (scsi_device_get(sdev))
3737 				continue;
3738 
3739 			spin_unlock_irqrestore(ap->lock, flags);
3740 			scsi_rescan_device(&(sdev->sdev_gendev));
3741 			scsi_device_put(sdev);
3742 			spin_lock_irqsave(ap->lock, flags);
3743 		}
3744 	}
3745 
3746 	spin_unlock_irqrestore(ap->lock, flags);
3747 	mutex_unlock(&ap->scsi_scan_mutex);
3748 }
3749 
3750 /**
3751  *	ata_sas_port_alloc - Allocate port for a SAS attached SATA device
3752  *	@host: ATA host container for all SAS ports
3753  *	@port_info: Information from low-level host driver
3754  *	@shost: SCSI host that the scsi device is attached to
3755  *
3756  *	LOCKING:
3757  *	PCI/etc. bus probe sem.
3758  *
3759  *	RETURNS:
3760  *	ata_port pointer on success / NULL on failure.
3761  */
3762 
3763 struct ata_port *ata_sas_port_alloc(struct ata_host *host,
3764 				    struct ata_port_info *port_info,
3765 				    struct Scsi_Host *shost)
3766 {
3767 	struct ata_port *ap;
3768 
3769 	ap = ata_port_alloc(host);
3770 	if (!ap)
3771 		return NULL;
3772 
3773 	ap->port_no = 0;
3774 	ap->lock = &host->lock;
3775 	ap->pio_mask = port_info->pio_mask;
3776 	ap->mwdma_mask = port_info->mwdma_mask;
3777 	ap->udma_mask = port_info->udma_mask;
3778 	ap->flags |= port_info->flags;
3779 	ap->ops = port_info->port_ops;
3780 	ap->cbl = ATA_CBL_SATA;
3781 
3782 	return ap;
3783 }
3784 EXPORT_SYMBOL_GPL(ata_sas_port_alloc);
3785 
3786 /**
3787  *	ata_sas_port_start - Set port up for dma.
3788  *	@ap: Port to initialize
3789  *
3790  *	Called just after data structures for each port are
3791  *	initialized.
3792  *
3793  *	May be used as the port_start() entry in ata_port_operations.
3794  *
3795  *	LOCKING:
3796  *	Inherited from caller.
3797  */
3798 int ata_sas_port_start(struct ata_port *ap)
3799 {
3800 	return 0;
3801 }
3802 EXPORT_SYMBOL_GPL(ata_sas_port_start);
3803 
3804 /**
3805  *	ata_port_stop - Undo ata_sas_port_start()
3806  *	@ap: Port to shut down
3807  *
3808  *	May be used as the port_stop() entry in ata_port_operations.
3809  *
3810  *	LOCKING:
3811  *	Inherited from caller.
3812  */
3813 
3814 void ata_sas_port_stop(struct ata_port *ap)
3815 {
3816 }
3817 EXPORT_SYMBOL_GPL(ata_sas_port_stop);
3818 
3819 /**
3820  *	ata_sas_port_init - Initialize a SATA device
3821  *	@ap: SATA port to initialize
3822  *
3823  *	LOCKING:
3824  *	PCI/etc. bus probe sem.
3825  *
3826  *	RETURNS:
3827  *	Zero on success, non-zero on error.
3828  */
3829 
3830 int ata_sas_port_init(struct ata_port *ap)
3831 {
3832 	int rc = ap->ops->port_start(ap);
3833 
3834 	if (!rc) {
3835 		ap->print_id = ata_print_id++;
3836 		rc = ata_port_probe(ap);
3837 	}
3838 
3839 	return rc;
3840 }
3841 EXPORT_SYMBOL_GPL(ata_sas_port_init);
3842 
3843 /**
3844  *	ata_sas_port_destroy - Destroy a SATA port allocated by ata_sas_port_alloc
3845  *	@ap: SATA port to destroy
3846  *
3847  */
3848 
3849 void ata_sas_port_destroy(struct ata_port *ap)
3850 {
3851 	if (ap->ops->port_stop)
3852 		ap->ops->port_stop(ap);
3853 	kfree(ap);
3854 }
3855 EXPORT_SYMBOL_GPL(ata_sas_port_destroy);
3856 
3857 /**
3858  *	ata_sas_slave_configure - Default slave_config routine for libata devices
3859  *	@sdev: SCSI device to configure
3860  *	@ap: ATA port to which SCSI device is attached
3861  *
3862  *	RETURNS:
3863  *	Zero.
3864  */
3865 
3866 int ata_sas_slave_configure(struct scsi_device *sdev, struct ata_port *ap)
3867 {
3868 	ata_scsi_sdev_config(sdev);
3869 	ata_scsi_dev_config(sdev, ap->link.device);
3870 	return 0;
3871 }
3872 EXPORT_SYMBOL_GPL(ata_sas_slave_configure);
3873 
3874 /**
3875  *	ata_sas_queuecmd - Issue SCSI cdb to libata-managed device
3876  *	@cmd: SCSI command to be sent
3877  *	@ap:	ATA port to which the command is being sent
3878  *
3879  *	RETURNS:
3880  *	Return value from __ata_scsi_queuecmd() if @cmd can be queued,
3881  *	0 otherwise.
3882  */
3883 
3884 int ata_sas_queuecmd(struct scsi_cmnd *cmd, struct ata_port *ap)
3885 {
3886 	int rc = 0;
3887 
3888 	ata_scsi_dump_cdb(ap, cmd);
3889 
3890 	if (likely(ata_dev_enabled(ap->link.device)))
3891 		rc = __ata_scsi_queuecmd(cmd, ap->link.device);
3892 	else {
3893 		cmd->result = (DID_BAD_TARGET << 16);
3894 		cmd->scsi_done(cmd);
3895 	}
3896 	return rc;
3897 }
3898 EXPORT_SYMBOL_GPL(ata_sas_queuecmd);
3899