xref: /openbmc/linux/drivers/ata/libata-scsi.c (revision 02b4e275)
1 /*
2  *  libata-scsi.c - helper library for ATA
3  *
4  *  Maintained by:  Tejun Heo <tj@kernel.org>
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 <linux/export.h>
41 #include <scsi/scsi.h>
42 #include <scsi/scsi_host.h>
43 #include <scsi/scsi_cmnd.h>
44 #include <scsi/scsi_eh.h>
45 #include <scsi/scsi_device.h>
46 #include <scsi/scsi_tcq.h>
47 #include <scsi/scsi_transport.h>
48 #include <linux/libata.h>
49 #include <linux/hdreg.h>
50 #include <linux/uaccess.h>
51 #include <linux/suspend.h>
52 #include <asm/unaligned.h>
53 
54 #include "libata.h"
55 #include "libata-transport.h"
56 
57 #define ATA_SCSI_RBUF_SIZE	4096
58 
59 static DEFINE_SPINLOCK(ata_scsi_rbuf_lock);
60 static u8 ata_scsi_rbuf[ATA_SCSI_RBUF_SIZE];
61 
62 typedef unsigned int (*ata_xlat_func_t)(struct ata_queued_cmd *qc);
63 
64 static struct ata_device *__ata_scsi_find_dev(struct ata_port *ap,
65 					const struct scsi_device *scsidev);
66 static struct ata_device *ata_scsi_find_dev(struct ata_port *ap,
67 					    const struct scsi_device *scsidev);
68 
69 #define RW_RECOVERY_MPAGE 0x1
70 #define RW_RECOVERY_MPAGE_LEN 12
71 #define CACHE_MPAGE 0x8
72 #define CACHE_MPAGE_LEN 20
73 #define CONTROL_MPAGE 0xa
74 #define CONTROL_MPAGE_LEN 12
75 #define ALL_MPAGES 0x3f
76 #define ALL_SUB_MPAGES 0xff
77 
78 
79 static const u8 def_rw_recovery_mpage[RW_RECOVERY_MPAGE_LEN] = {
80 	RW_RECOVERY_MPAGE,
81 	RW_RECOVERY_MPAGE_LEN - 2,
82 	(1 << 7),	/* AWRE */
83 	0,		/* read retry count */
84 	0, 0, 0, 0,
85 	0,		/* write retry count */
86 	0, 0, 0
87 };
88 
89 static const u8 def_cache_mpage[CACHE_MPAGE_LEN] = {
90 	CACHE_MPAGE,
91 	CACHE_MPAGE_LEN - 2,
92 	0,		/* contains WCE, needs to be 0 for logic */
93 	0, 0, 0, 0, 0, 0, 0, 0, 0,
94 	0,		/* contains DRA, needs to be 0 for logic */
95 	0, 0, 0, 0, 0, 0, 0
96 };
97 
98 static const u8 def_control_mpage[CONTROL_MPAGE_LEN] = {
99 	CONTROL_MPAGE,
100 	CONTROL_MPAGE_LEN - 2,
101 	2,	/* DSENSE=0, GLTSD=1 */
102 	0,	/* [QAM+QERR may be 1, see 05-359r1] */
103 	0, 0, 0, 0, 0xff, 0xff,
104 	0, 30	/* extended self test time, see 05-359r1 */
105 };
106 
107 static const char *ata_lpm_policy_names[] = {
108 	[ATA_LPM_UNKNOWN]	= "max_performance",
109 	[ATA_LPM_MAX_POWER]	= "max_performance",
110 	[ATA_LPM_MED_POWER]	= "medium_power",
111 	[ATA_LPM_MIN_POWER]	= "min_power",
112 };
113 
114 static ssize_t ata_scsi_lpm_store(struct device *device,
115 				  struct device_attribute *attr,
116 				  const char *buf, size_t count)
117 {
118 	struct Scsi_Host *shost = class_to_shost(device);
119 	struct ata_port *ap = ata_shost_to_port(shost);
120 	struct ata_link *link;
121 	struct ata_device *dev;
122 	enum ata_lpm_policy policy;
123 	unsigned long flags;
124 
125 	/* UNKNOWN is internal state, iterate from MAX_POWER */
126 	for (policy = ATA_LPM_MAX_POWER;
127 	     policy < ARRAY_SIZE(ata_lpm_policy_names); policy++) {
128 		const char *name = ata_lpm_policy_names[policy];
129 
130 		if (strncmp(name, buf, strlen(name)) == 0)
131 			break;
132 	}
133 	if (policy == ARRAY_SIZE(ata_lpm_policy_names))
134 		return -EINVAL;
135 
136 	spin_lock_irqsave(ap->lock, flags);
137 
138 	ata_for_each_link(link, ap, EDGE) {
139 		ata_for_each_dev(dev, &ap->link, ENABLED) {
140 			if (dev->horkage & ATA_HORKAGE_NOLPM) {
141 				count = -EOPNOTSUPP;
142 				goto out_unlock;
143 			}
144 		}
145 	}
146 
147 	ap->target_lpm_policy = policy;
148 	ata_port_schedule_eh(ap);
149 out_unlock:
150 	spin_unlock_irqrestore(ap->lock, flags);
151 	return count;
152 }
153 
154 static ssize_t ata_scsi_lpm_show(struct device *dev,
155 				 struct device_attribute *attr, char *buf)
156 {
157 	struct Scsi_Host *shost = class_to_shost(dev);
158 	struct ata_port *ap = ata_shost_to_port(shost);
159 
160 	if (ap->target_lpm_policy >= ARRAY_SIZE(ata_lpm_policy_names))
161 		return -EINVAL;
162 
163 	return snprintf(buf, PAGE_SIZE, "%s\n",
164 			ata_lpm_policy_names[ap->target_lpm_policy]);
165 }
166 DEVICE_ATTR(link_power_management_policy, S_IRUGO | S_IWUSR,
167 	    ata_scsi_lpm_show, ata_scsi_lpm_store);
168 EXPORT_SYMBOL_GPL(dev_attr_link_power_management_policy);
169 
170 static ssize_t ata_scsi_park_show(struct device *device,
171 				  struct device_attribute *attr, char *buf)
172 {
173 	struct scsi_device *sdev = to_scsi_device(device);
174 	struct ata_port *ap;
175 	struct ata_link *link;
176 	struct ata_device *dev;
177 	unsigned long flags, now;
178 	unsigned int uninitialized_var(msecs);
179 	int rc = 0;
180 
181 	ap = ata_shost_to_port(sdev->host);
182 
183 	spin_lock_irqsave(ap->lock, flags);
184 	dev = ata_scsi_find_dev(ap, sdev);
185 	if (!dev) {
186 		rc = -ENODEV;
187 		goto unlock;
188 	}
189 	if (dev->flags & ATA_DFLAG_NO_UNLOAD) {
190 		rc = -EOPNOTSUPP;
191 		goto unlock;
192 	}
193 
194 	link = dev->link;
195 	now = jiffies;
196 	if (ap->pflags & ATA_PFLAG_EH_IN_PROGRESS &&
197 	    link->eh_context.unloaded_mask & (1 << dev->devno) &&
198 	    time_after(dev->unpark_deadline, now))
199 		msecs = jiffies_to_msecs(dev->unpark_deadline - now);
200 	else
201 		msecs = 0;
202 
203 unlock:
204 	spin_unlock_irq(ap->lock);
205 
206 	return rc ? rc : snprintf(buf, 20, "%u\n", msecs);
207 }
208 
209 static ssize_t ata_scsi_park_store(struct device *device,
210 				   struct device_attribute *attr,
211 				   const char *buf, size_t len)
212 {
213 	struct scsi_device *sdev = to_scsi_device(device);
214 	struct ata_port *ap;
215 	struct ata_device *dev;
216 	long int input;
217 	unsigned long flags;
218 	int rc;
219 
220 	rc = kstrtol(buf, 10, &input);
221 	if (rc)
222 		return rc;
223 	if (input < -2)
224 		return -EINVAL;
225 	if (input > ATA_TMOUT_MAX_PARK) {
226 		rc = -EOVERFLOW;
227 		input = ATA_TMOUT_MAX_PARK;
228 	}
229 
230 	ap = ata_shost_to_port(sdev->host);
231 
232 	spin_lock_irqsave(ap->lock, flags);
233 	dev = ata_scsi_find_dev(ap, sdev);
234 	if (unlikely(!dev)) {
235 		rc = -ENODEV;
236 		goto unlock;
237 	}
238 	if (dev->class != ATA_DEV_ATA &&
239 	    dev->class != ATA_DEV_ZAC) {
240 		rc = -EOPNOTSUPP;
241 		goto unlock;
242 	}
243 
244 	if (input >= 0) {
245 		if (dev->flags & ATA_DFLAG_NO_UNLOAD) {
246 			rc = -EOPNOTSUPP;
247 			goto unlock;
248 		}
249 
250 		dev->unpark_deadline = ata_deadline(jiffies, input);
251 		dev->link->eh_info.dev_action[dev->devno] |= ATA_EH_PARK;
252 		ata_port_schedule_eh(ap);
253 		complete(&ap->park_req_pending);
254 	} else {
255 		switch (input) {
256 		case -1:
257 			dev->flags &= ~ATA_DFLAG_NO_UNLOAD;
258 			break;
259 		case -2:
260 			dev->flags |= ATA_DFLAG_NO_UNLOAD;
261 			break;
262 		}
263 	}
264 unlock:
265 	spin_unlock_irqrestore(ap->lock, flags);
266 
267 	return rc ? rc : len;
268 }
269 DEVICE_ATTR(unload_heads, S_IRUGO | S_IWUSR,
270 	    ata_scsi_park_show, ata_scsi_park_store);
271 EXPORT_SYMBOL_GPL(dev_attr_unload_heads);
272 
273 void ata_scsi_set_sense(struct scsi_cmnd *cmd, u8 sk, u8 asc, u8 ascq)
274 {
275 	if (!cmd)
276 		return;
277 
278 	cmd->result = (DRIVER_SENSE << 24) | SAM_STAT_CHECK_CONDITION;
279 
280 	scsi_build_sense_buffer(0, cmd->sense_buffer, sk, asc, ascq);
281 }
282 
283 void ata_scsi_set_sense_information(struct scsi_cmnd *cmd,
284 				    const struct ata_taskfile *tf)
285 {
286 	u64 information;
287 
288 	if (!cmd)
289 		return;
290 
291 	information = ata_tf_read_block(tf, NULL);
292 	scsi_set_sense_information(cmd->sense_buffer, information);
293 }
294 
295 static ssize_t
296 ata_scsi_em_message_store(struct device *dev, struct device_attribute *attr,
297 			  const char *buf, size_t count)
298 {
299 	struct Scsi_Host *shost = class_to_shost(dev);
300 	struct ata_port *ap = ata_shost_to_port(shost);
301 	if (ap->ops->em_store && (ap->flags & ATA_FLAG_EM))
302 		return ap->ops->em_store(ap, buf, count);
303 	return -EINVAL;
304 }
305 
306 static ssize_t
307 ata_scsi_em_message_show(struct device *dev, struct device_attribute *attr,
308 			 char *buf)
309 {
310 	struct Scsi_Host *shost = class_to_shost(dev);
311 	struct ata_port *ap = ata_shost_to_port(shost);
312 
313 	if (ap->ops->em_show && (ap->flags & ATA_FLAG_EM))
314 		return ap->ops->em_show(ap, buf);
315 	return -EINVAL;
316 }
317 DEVICE_ATTR(em_message, S_IRUGO | S_IWUSR,
318 		ata_scsi_em_message_show, ata_scsi_em_message_store);
319 EXPORT_SYMBOL_GPL(dev_attr_em_message);
320 
321 static ssize_t
322 ata_scsi_em_message_type_show(struct device *dev, struct device_attribute *attr,
323 			      char *buf)
324 {
325 	struct Scsi_Host *shost = class_to_shost(dev);
326 	struct ata_port *ap = ata_shost_to_port(shost);
327 
328 	return snprintf(buf, 23, "%d\n", ap->em_message_type);
329 }
330 DEVICE_ATTR(em_message_type, S_IRUGO,
331 		  ata_scsi_em_message_type_show, NULL);
332 EXPORT_SYMBOL_GPL(dev_attr_em_message_type);
333 
334 static ssize_t
335 ata_scsi_activity_show(struct device *dev, struct device_attribute *attr,
336 		char *buf)
337 {
338 	struct scsi_device *sdev = to_scsi_device(dev);
339 	struct ata_port *ap = ata_shost_to_port(sdev->host);
340 	struct ata_device *atadev = ata_scsi_find_dev(ap, sdev);
341 
342 	if (atadev && ap->ops->sw_activity_show &&
343 	    (ap->flags & ATA_FLAG_SW_ACTIVITY))
344 		return ap->ops->sw_activity_show(atadev, buf);
345 	return -EINVAL;
346 }
347 
348 static ssize_t
349 ata_scsi_activity_store(struct device *dev, struct device_attribute *attr,
350 	const char *buf, size_t count)
351 {
352 	struct scsi_device *sdev = to_scsi_device(dev);
353 	struct ata_port *ap = ata_shost_to_port(sdev->host);
354 	struct ata_device *atadev = ata_scsi_find_dev(ap, sdev);
355 	enum sw_activity val;
356 	int rc;
357 
358 	if (atadev && ap->ops->sw_activity_store &&
359 	    (ap->flags & ATA_FLAG_SW_ACTIVITY)) {
360 		val = simple_strtoul(buf, NULL, 0);
361 		switch (val) {
362 		case OFF: case BLINK_ON: case BLINK_OFF:
363 			rc = ap->ops->sw_activity_store(atadev, val);
364 			if (!rc)
365 				return count;
366 			else
367 				return rc;
368 		}
369 	}
370 	return -EINVAL;
371 }
372 DEVICE_ATTR(sw_activity, S_IWUSR | S_IRUGO, ata_scsi_activity_show,
373 			ata_scsi_activity_store);
374 EXPORT_SYMBOL_GPL(dev_attr_sw_activity);
375 
376 struct device_attribute *ata_common_sdev_attrs[] = {
377 	&dev_attr_unload_heads,
378 	NULL
379 };
380 EXPORT_SYMBOL_GPL(ata_common_sdev_attrs);
381 
382 static void ata_scsi_invalid_field(struct scsi_cmnd *cmd)
383 {
384 	ata_scsi_set_sense(cmd, ILLEGAL_REQUEST, 0x24, 0x0);
385 	/* "Invalid field in cbd" */
386 	cmd->scsi_done(cmd);
387 }
388 
389 /**
390  *	ata_std_bios_param - generic bios head/sector/cylinder calculator used by sd.
391  *	@sdev: SCSI device for which BIOS geometry is to be determined
392  *	@bdev: block device associated with @sdev
393  *	@capacity: capacity of SCSI device
394  *	@geom: location to which geometry will be output
395  *
396  *	Generic bios head/sector/cylinder calculator
397  *	used by sd. Most BIOSes nowadays expect a XXX/255/16  (CHS)
398  *	mapping. Some situations may arise where the disk is not
399  *	bootable if this is not used.
400  *
401  *	LOCKING:
402  *	Defined by the SCSI layer.  We don't really care.
403  *
404  *	RETURNS:
405  *	Zero.
406  */
407 int ata_std_bios_param(struct scsi_device *sdev, struct block_device *bdev,
408 		       sector_t capacity, int geom[])
409 {
410 	geom[0] = 255;
411 	geom[1] = 63;
412 	sector_div(capacity, 255*63);
413 	geom[2] = capacity;
414 
415 	return 0;
416 }
417 
418 /**
419  *	ata_scsi_unlock_native_capacity - unlock native capacity
420  *	@sdev: SCSI device to adjust device capacity for
421  *
422  *	This function is called if a partition on @sdev extends beyond
423  *	the end of the device.  It requests EH to unlock HPA.
424  *
425  *	LOCKING:
426  *	Defined by the SCSI layer.  Might sleep.
427  */
428 void ata_scsi_unlock_native_capacity(struct scsi_device *sdev)
429 {
430 	struct ata_port *ap = ata_shost_to_port(sdev->host);
431 	struct ata_device *dev;
432 	unsigned long flags;
433 
434 	spin_lock_irqsave(ap->lock, flags);
435 
436 	dev = ata_scsi_find_dev(ap, sdev);
437 	if (dev && dev->n_sectors < dev->n_native_sectors) {
438 		dev->flags |= ATA_DFLAG_UNLOCK_HPA;
439 		dev->link->eh_info.action |= ATA_EH_RESET;
440 		ata_port_schedule_eh(ap);
441 	}
442 
443 	spin_unlock_irqrestore(ap->lock, flags);
444 	ata_port_wait_eh(ap);
445 }
446 
447 /**
448  *	ata_get_identity - Handler for HDIO_GET_IDENTITY ioctl
449  *	@ap: target port
450  *	@sdev: SCSI device to get identify data for
451  *	@arg: User buffer area for identify data
452  *
453  *	LOCKING:
454  *	Defined by the SCSI layer.  We don't really care.
455  *
456  *	RETURNS:
457  *	Zero on success, negative errno on error.
458  */
459 static int ata_get_identity(struct ata_port *ap, struct scsi_device *sdev,
460 			    void __user *arg)
461 {
462 	struct ata_device *dev = ata_scsi_find_dev(ap, sdev);
463 	u16 __user *dst = arg;
464 	char buf[40];
465 
466 	if (!dev)
467 		return -ENOMSG;
468 
469 	if (copy_to_user(dst, dev->id, ATA_ID_WORDS * sizeof(u16)))
470 		return -EFAULT;
471 
472 	ata_id_string(dev->id, buf, ATA_ID_PROD, ATA_ID_PROD_LEN);
473 	if (copy_to_user(dst + ATA_ID_PROD, buf, ATA_ID_PROD_LEN))
474 		return -EFAULT;
475 
476 	ata_id_string(dev->id, buf, ATA_ID_FW_REV, ATA_ID_FW_REV_LEN);
477 	if (copy_to_user(dst + ATA_ID_FW_REV, buf, ATA_ID_FW_REV_LEN))
478 		return -EFAULT;
479 
480 	ata_id_string(dev->id, buf, ATA_ID_SERNO, ATA_ID_SERNO_LEN);
481 	if (copy_to_user(dst + ATA_ID_SERNO, buf, ATA_ID_SERNO_LEN))
482 		return -EFAULT;
483 
484 	return 0;
485 }
486 
487 /**
488  *	ata_cmd_ioctl - Handler for HDIO_DRIVE_CMD ioctl
489  *	@scsidev: Device to which we are issuing command
490  *	@arg: User provided data for issuing command
491  *
492  *	LOCKING:
493  *	Defined by the SCSI layer.  We don't really care.
494  *
495  *	RETURNS:
496  *	Zero on success, negative errno on error.
497  */
498 int ata_cmd_ioctl(struct scsi_device *scsidev, void __user *arg)
499 {
500 	int rc = 0;
501 	u8 scsi_cmd[MAX_COMMAND_SIZE];
502 	u8 args[4], *argbuf = NULL, *sensebuf = NULL;
503 	int argsize = 0;
504 	enum dma_data_direction data_dir;
505 	int cmd_result;
506 
507 	if (arg == NULL)
508 		return -EINVAL;
509 
510 	if (copy_from_user(args, arg, sizeof(args)))
511 		return -EFAULT;
512 
513 	sensebuf = kzalloc(SCSI_SENSE_BUFFERSIZE, GFP_NOIO);
514 	if (!sensebuf)
515 		return -ENOMEM;
516 
517 	memset(scsi_cmd, 0, sizeof(scsi_cmd));
518 
519 	if (args[3]) {
520 		argsize = ATA_SECT_SIZE * args[3];
521 		argbuf = kmalloc(argsize, GFP_KERNEL);
522 		if (argbuf == NULL) {
523 			rc = -ENOMEM;
524 			goto error;
525 		}
526 
527 		scsi_cmd[1]  = (4 << 1); /* PIO Data-in */
528 		scsi_cmd[2]  = 0x0e;     /* no off.line or cc, read from dev,
529 					    block count in sector count field */
530 		data_dir = DMA_FROM_DEVICE;
531 	} else {
532 		scsi_cmd[1]  = (3 << 1); /* Non-data */
533 		scsi_cmd[2]  = 0x20;     /* cc but no off.line or data xfer */
534 		data_dir = DMA_NONE;
535 	}
536 
537 	scsi_cmd[0] = ATA_16;
538 
539 	scsi_cmd[4] = args[2];
540 	if (args[0] == ATA_CMD_SMART) { /* hack -- ide driver does this too */
541 		scsi_cmd[6]  = args[3];
542 		scsi_cmd[8]  = args[1];
543 		scsi_cmd[10] = 0x4f;
544 		scsi_cmd[12] = 0xc2;
545 	} else {
546 		scsi_cmd[6]  = args[1];
547 	}
548 	scsi_cmd[14] = args[0];
549 
550 	/* Good values for timeout and retries?  Values below
551 	   from scsi_ioctl_send_command() for default case... */
552 	cmd_result = scsi_execute(scsidev, scsi_cmd, data_dir, argbuf, argsize,
553 				  sensebuf, (10*HZ), 5, 0, NULL);
554 
555 	if (driver_byte(cmd_result) == DRIVER_SENSE) {/* sense data available */
556 		u8 *desc = sensebuf + 8;
557 		cmd_result &= ~(0xFF<<24); /* DRIVER_SENSE is not an error */
558 
559 		/* If we set cc then ATA pass-through will cause a
560 		 * check condition even if no error. Filter that. */
561 		if (cmd_result & SAM_STAT_CHECK_CONDITION) {
562 			struct scsi_sense_hdr sshdr;
563 			scsi_normalize_sense(sensebuf, SCSI_SENSE_BUFFERSIZE,
564 					     &sshdr);
565 			if (sshdr.sense_key == RECOVERED_ERROR &&
566 			    sshdr.asc == 0 && sshdr.ascq == 0x1d)
567 				cmd_result &= ~SAM_STAT_CHECK_CONDITION;
568 		}
569 
570 		/* Send userspace a few ATA registers (same as drivers/ide) */
571 		if (sensebuf[0] == 0x72 &&	/* format is "descriptor" */
572 		    desc[0] == 0x09) {		/* code is "ATA Descriptor" */
573 			args[0] = desc[13];	/* status */
574 			args[1] = desc[3];	/* error */
575 			args[2] = desc[5];	/* sector count (0:7) */
576 			if (copy_to_user(arg, args, sizeof(args)))
577 				rc = -EFAULT;
578 		}
579 	}
580 
581 
582 	if (cmd_result) {
583 		rc = -EIO;
584 		goto error;
585 	}
586 
587 	if ((argbuf)
588 	 && copy_to_user(arg + sizeof(args), argbuf, argsize))
589 		rc = -EFAULT;
590 error:
591 	kfree(sensebuf);
592 	kfree(argbuf);
593 	return rc;
594 }
595 
596 /**
597  *	ata_task_ioctl - Handler for HDIO_DRIVE_TASK ioctl
598  *	@scsidev: Device to which we are issuing command
599  *	@arg: User provided data for issuing command
600  *
601  *	LOCKING:
602  *	Defined by the SCSI layer.  We don't really care.
603  *
604  *	RETURNS:
605  *	Zero on success, negative errno on error.
606  */
607 int ata_task_ioctl(struct scsi_device *scsidev, void __user *arg)
608 {
609 	int rc = 0;
610 	u8 scsi_cmd[MAX_COMMAND_SIZE];
611 	u8 args[7], *sensebuf = NULL;
612 	int cmd_result;
613 
614 	if (arg == NULL)
615 		return -EINVAL;
616 
617 	if (copy_from_user(args, arg, sizeof(args)))
618 		return -EFAULT;
619 
620 	sensebuf = kzalloc(SCSI_SENSE_BUFFERSIZE, GFP_NOIO);
621 	if (!sensebuf)
622 		return -ENOMEM;
623 
624 	memset(scsi_cmd, 0, sizeof(scsi_cmd));
625 	scsi_cmd[0]  = ATA_16;
626 	scsi_cmd[1]  = (3 << 1); /* Non-data */
627 	scsi_cmd[2]  = 0x20;     /* cc but no off.line or data xfer */
628 	scsi_cmd[4]  = args[1];
629 	scsi_cmd[6]  = args[2];
630 	scsi_cmd[8]  = args[3];
631 	scsi_cmd[10] = args[4];
632 	scsi_cmd[12] = args[5];
633 	scsi_cmd[13] = args[6] & 0x4f;
634 	scsi_cmd[14] = args[0];
635 
636 	/* Good values for timeout and retries?  Values below
637 	   from scsi_ioctl_send_command() for default case... */
638 	cmd_result = scsi_execute(scsidev, scsi_cmd, DMA_NONE, NULL, 0,
639 				sensebuf, (10*HZ), 5, 0, NULL);
640 
641 	if (driver_byte(cmd_result) == DRIVER_SENSE) {/* sense data available */
642 		u8 *desc = sensebuf + 8;
643 		cmd_result &= ~(0xFF<<24); /* DRIVER_SENSE is not an error */
644 
645 		/* If we set cc then ATA pass-through will cause a
646 		 * check condition even if no error. Filter that. */
647 		if (cmd_result & SAM_STAT_CHECK_CONDITION) {
648 			struct scsi_sense_hdr sshdr;
649 			scsi_normalize_sense(sensebuf, SCSI_SENSE_BUFFERSIZE,
650 						&sshdr);
651 			if (sshdr.sense_key == RECOVERED_ERROR &&
652 			    sshdr.asc == 0 && sshdr.ascq == 0x1d)
653 				cmd_result &= ~SAM_STAT_CHECK_CONDITION;
654 		}
655 
656 		/* Send userspace ATA registers */
657 		if (sensebuf[0] == 0x72 &&	/* format is "descriptor" */
658 				desc[0] == 0x09) {/* code is "ATA Descriptor" */
659 			args[0] = desc[13];	/* status */
660 			args[1] = desc[3];	/* error */
661 			args[2] = desc[5];	/* sector count (0:7) */
662 			args[3] = desc[7];	/* lbal */
663 			args[4] = desc[9];	/* lbam */
664 			args[5] = desc[11];	/* lbah */
665 			args[6] = desc[12];	/* select */
666 			if (copy_to_user(arg, args, sizeof(args)))
667 				rc = -EFAULT;
668 		}
669 	}
670 
671 	if (cmd_result) {
672 		rc = -EIO;
673 		goto error;
674 	}
675 
676  error:
677 	kfree(sensebuf);
678 	return rc;
679 }
680 
681 static int ata_ioc32(struct ata_port *ap)
682 {
683 	if (ap->flags & ATA_FLAG_PIO_DMA)
684 		return 1;
685 	if (ap->pflags & ATA_PFLAG_PIO32)
686 		return 1;
687 	return 0;
688 }
689 
690 int ata_sas_scsi_ioctl(struct ata_port *ap, struct scsi_device *scsidev,
691 		     int cmd, void __user *arg)
692 {
693 	int val = -EINVAL, rc = -EINVAL;
694 	unsigned long flags;
695 
696 	switch (cmd) {
697 	case ATA_IOC_GET_IO32:
698 		spin_lock_irqsave(ap->lock, flags);
699 		val = ata_ioc32(ap);
700 		spin_unlock_irqrestore(ap->lock, flags);
701 		if (copy_to_user(arg, &val, 1))
702 			return -EFAULT;
703 		return 0;
704 
705 	case ATA_IOC_SET_IO32:
706 		val = (unsigned long) arg;
707 		rc = 0;
708 		spin_lock_irqsave(ap->lock, flags);
709 		if (ap->pflags & ATA_PFLAG_PIO32CHANGE) {
710 			if (val)
711 				ap->pflags |= ATA_PFLAG_PIO32;
712 			else
713 				ap->pflags &= ~ATA_PFLAG_PIO32;
714 		} else {
715 			if (val != ata_ioc32(ap))
716 				rc = -EINVAL;
717 		}
718 		spin_unlock_irqrestore(ap->lock, flags);
719 		return rc;
720 
721 	case HDIO_GET_IDENTITY:
722 		return ata_get_identity(ap, scsidev, arg);
723 
724 	case HDIO_DRIVE_CMD:
725 		if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
726 			return -EACCES;
727 		return ata_cmd_ioctl(scsidev, arg);
728 
729 	case HDIO_DRIVE_TASK:
730 		if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
731 			return -EACCES;
732 		return ata_task_ioctl(scsidev, arg);
733 
734 	default:
735 		rc = -ENOTTY;
736 		break;
737 	}
738 
739 	return rc;
740 }
741 EXPORT_SYMBOL_GPL(ata_sas_scsi_ioctl);
742 
743 int ata_scsi_ioctl(struct scsi_device *scsidev, int cmd, void __user *arg)
744 {
745 	return ata_sas_scsi_ioctl(ata_shost_to_port(scsidev->host),
746 				scsidev, cmd, arg);
747 }
748 EXPORT_SYMBOL_GPL(ata_scsi_ioctl);
749 
750 /**
751  *	ata_scsi_qc_new - acquire new ata_queued_cmd reference
752  *	@dev: ATA device to which the new command is attached
753  *	@cmd: SCSI command that originated this ATA command
754  *
755  *	Obtain a reference to an unused ata_queued_cmd structure,
756  *	which is the basic libata structure representing a single
757  *	ATA command sent to the hardware.
758  *
759  *	If a command was available, fill in the SCSI-specific
760  *	portions of the structure with information on the
761  *	current command.
762  *
763  *	LOCKING:
764  *	spin_lock_irqsave(host lock)
765  *
766  *	RETURNS:
767  *	Command allocated, or %NULL if none available.
768  */
769 static struct ata_queued_cmd *ata_scsi_qc_new(struct ata_device *dev,
770 					      struct scsi_cmnd *cmd)
771 {
772 	struct ata_queued_cmd *qc;
773 
774 	qc = ata_qc_new_init(dev, cmd->request->tag);
775 	if (qc) {
776 		qc->scsicmd = cmd;
777 		qc->scsidone = cmd->scsi_done;
778 
779 		qc->sg = scsi_sglist(cmd);
780 		qc->n_elem = scsi_sg_count(cmd);
781 	} else {
782 		cmd->result = (DID_OK << 16) | (QUEUE_FULL << 1);
783 		cmd->scsi_done(cmd);
784 	}
785 
786 	return qc;
787 }
788 
789 static void ata_qc_set_pc_nbytes(struct ata_queued_cmd *qc)
790 {
791 	struct scsi_cmnd *scmd = qc->scsicmd;
792 
793 	qc->extrabytes = scmd->request->extra_len;
794 	qc->nbytes = scsi_bufflen(scmd) + qc->extrabytes;
795 }
796 
797 /**
798  *	ata_dump_status - user friendly display of error info
799  *	@id: id of the port in question
800  *	@tf: ptr to filled out taskfile
801  *
802  *	Decode and dump the ATA error/status registers for the user so
803  *	that they have some idea what really happened at the non
804  *	make-believe layer.
805  *
806  *	LOCKING:
807  *	inherited from caller
808  */
809 static void ata_dump_status(unsigned id, struct ata_taskfile *tf)
810 {
811 	u8 stat = tf->command, err = tf->feature;
812 
813 	printk(KERN_WARNING "ata%u: status=0x%02x { ", id, stat);
814 	if (stat & ATA_BUSY) {
815 		printk("Busy }\n");	/* Data is not valid in this case */
816 	} else {
817 		if (stat & ATA_DRDY)	printk("DriveReady ");
818 		if (stat & ATA_DF)	printk("DeviceFault ");
819 		if (stat & ATA_DSC)	printk("SeekComplete ");
820 		if (stat & ATA_DRQ)	printk("DataRequest ");
821 		if (stat & ATA_CORR)	printk("CorrectedError ");
822 		if (stat & ATA_SENSE)	printk("Sense ");
823 		if (stat & ATA_ERR)	printk("Error ");
824 		printk("}\n");
825 
826 		if (err) {
827 			printk(KERN_WARNING "ata%u: error=0x%02x { ", id, err);
828 			if (err & ATA_ABORTED)	printk("DriveStatusError ");
829 			if (err & ATA_ICRC) {
830 				if (err & ATA_ABORTED)
831 						printk("BadCRC ");
832 				else		printk("Sector ");
833 			}
834 			if (err & ATA_UNC)	printk("UncorrectableError ");
835 			if (err & ATA_IDNF)	printk("SectorIdNotFound ");
836 			if (err & ATA_TRK0NF)	printk("TrackZeroNotFound ");
837 			if (err & ATA_AMNF)	printk("AddrMarkNotFound ");
838 			printk("}\n");
839 		}
840 	}
841 }
842 
843 /**
844  *	ata_to_sense_error - convert ATA error to SCSI error
845  *	@id: ATA device number
846  *	@drv_stat: value contained in ATA status register
847  *	@drv_err: value contained in ATA error register
848  *	@sk: the sense key we'll fill out
849  *	@asc: the additional sense code we'll fill out
850  *	@ascq: the additional sense code qualifier we'll fill out
851  *	@verbose: be verbose
852  *
853  *	Converts an ATA error into a SCSI error.  Fill out pointers to
854  *	SK, ASC, and ASCQ bytes for later use in fixed or descriptor
855  *	format sense blocks.
856  *
857  *	LOCKING:
858  *	spin_lock_irqsave(host lock)
859  */
860 static void ata_to_sense_error(unsigned id, u8 drv_stat, u8 drv_err, u8 *sk,
861 			       u8 *asc, u8 *ascq, int verbose)
862 {
863 	int i;
864 
865 	/* Based on the 3ware driver translation table */
866 	static const unsigned char sense_table[][4] = {
867 		/* BBD|ECC|ID|MAR */
868 		{0xd1,		ABORTED_COMMAND, 0x00, 0x00},
869 			// Device busy                  Aborted command
870 		/* BBD|ECC|ID */
871 		{0xd0,		ABORTED_COMMAND, 0x00, 0x00},
872 			// Device busy                  Aborted command
873 		/* ECC|MC|MARK */
874 		{0x61,		HARDWARE_ERROR, 0x00, 0x00},
875 			// Device fault                 Hardware error
876 		/* ICRC|ABRT */		/* NB: ICRC & !ABRT is BBD */
877 		{0x84,		ABORTED_COMMAND, 0x47, 0x00},
878 			// Data CRC error               SCSI parity error
879 		/* MC|ID|ABRT|TRK0|MARK */
880 		{0x37,		NOT_READY, 0x04, 0x00},
881 			// Unit offline                 Not ready
882 		/* MCR|MARK */
883 		{0x09,		NOT_READY, 0x04, 0x00},
884 			// Unrecovered disk error       Not ready
885 		/*  Bad address mark */
886 		{0x01,		MEDIUM_ERROR, 0x13, 0x00},
887 			// Address mark not found for data field
888 		/* TRK0 - Track 0 not found */
889 		{0x02,		HARDWARE_ERROR, 0x00, 0x00},
890 			// Hardware error
891 		/* Abort: 0x04 is not translated here, see below */
892 		/* Media change request */
893 		{0x08,		NOT_READY, 0x04, 0x00},
894 			// FIXME: faking offline
895 		/* SRV/IDNF - ID not found */
896 		{0x10,		ILLEGAL_REQUEST, 0x21, 0x00},
897 			// Logical address out of range
898 		/* MC - Media Changed */
899 		{0x20,		UNIT_ATTENTION, 0x28, 0x00},
900 			// Not ready to ready change, medium may have changed
901 		/* ECC - Uncorrectable ECC error */
902 		{0x40,		MEDIUM_ERROR, 0x11, 0x04},
903 			// Unrecovered read error
904 		/* BBD - block marked bad */
905 		{0x80,		MEDIUM_ERROR, 0x11, 0x04},
906 			// Block marked bad	Medium error, unrecovered read error
907 		{0xFF, 0xFF, 0xFF, 0xFF}, // END mark
908 	};
909 	static const unsigned char stat_table[][4] = {
910 		/* Must be first because BUSY means no other bits valid */
911 		{0x80,		ABORTED_COMMAND, 0x47, 0x00},
912 		// Busy, fake parity for now
913 		{0x40,		ILLEGAL_REQUEST, 0x21, 0x04},
914 		// Device ready, unaligned write command
915 		{0x20,		HARDWARE_ERROR,  0x44, 0x00},
916 		// Device fault, internal target failure
917 		{0x08,		ABORTED_COMMAND, 0x47, 0x00},
918 		// Timed out in xfer, fake parity for now
919 		{0x04,		RECOVERED_ERROR, 0x11, 0x00},
920 		// Recovered ECC error	  Medium error, recovered
921 		{0xFF, 0xFF, 0xFF, 0xFF}, // END mark
922 	};
923 
924 	/*
925 	 *	Is this an error we can process/parse
926 	 */
927 	if (drv_stat & ATA_BUSY) {
928 		drv_err = 0;	/* Ignore the err bits, they're invalid */
929 	}
930 
931 	if (drv_err) {
932 		/* Look for drv_err */
933 		for (i = 0; sense_table[i][0] != 0xFF; i++) {
934 			/* Look for best matches first */
935 			if ((sense_table[i][0] & drv_err) ==
936 			    sense_table[i][0]) {
937 				*sk = sense_table[i][1];
938 				*asc = sense_table[i][2];
939 				*ascq = sense_table[i][3];
940 				goto translate_done;
941 			}
942 		}
943 	}
944 
945 	/*
946 	 * Fall back to interpreting status bits.  Note that if the drv_err
947 	 * has only the ABRT bit set, we decode drv_stat.  ABRT by itself
948 	 * is not descriptive enough.
949 	 */
950 	for (i = 0; stat_table[i][0] != 0xFF; i++) {
951 		if (stat_table[i][0] & drv_stat) {
952 			*sk = stat_table[i][1];
953 			*asc = stat_table[i][2];
954 			*ascq = stat_table[i][3];
955 			goto translate_done;
956 		}
957 	}
958 
959 	/*
960 	 * We need a sensible error return here, which is tricky, and one
961 	 * that won't cause people to do things like return a disk wrongly.
962 	 */
963 	*sk = ABORTED_COMMAND;
964 	*asc = 0x00;
965 	*ascq = 0x00;
966 
967  translate_done:
968 	if (verbose)
969 		printk(KERN_ERR "ata%u: translated ATA stat/err 0x%02x/%02x "
970 		       "to SCSI SK/ASC/ASCQ 0x%x/%02x/%02x\n",
971 		       id, drv_stat, drv_err, *sk, *asc, *ascq);
972 	return;
973 }
974 
975 /*
976  *	ata_gen_passthru_sense - Generate check condition sense block.
977  *	@qc: Command that completed.
978  *
979  *	This function is specific to the ATA descriptor format sense
980  *	block specified for the ATA pass through commands.  Regardless
981  *	of whether the command errored or not, return a sense
982  *	block. Copy all controller registers into the sense
983  *	block. If there was no error, we get the request from an ATA
984  *	passthrough command, so we use the following sense data:
985  *	sk = RECOVERED ERROR
986  *	asc,ascq = ATA PASS-THROUGH INFORMATION AVAILABLE
987  *
988  *
989  *	LOCKING:
990  *	None.
991  */
992 static void ata_gen_passthru_sense(struct ata_queued_cmd *qc)
993 {
994 	struct scsi_cmnd *cmd = qc->scsicmd;
995 	struct ata_taskfile *tf = &qc->result_tf;
996 	unsigned char *sb = cmd->sense_buffer;
997 	unsigned char *desc = sb + 8;
998 	int verbose = qc->ap->ops->error_handler == NULL;
999 
1000 	memset(sb, 0, SCSI_SENSE_BUFFERSIZE);
1001 
1002 	cmd->result = (DRIVER_SENSE << 24) | SAM_STAT_CHECK_CONDITION;
1003 
1004 	/*
1005 	 * Use ata_to_sense_error() to map status register bits
1006 	 * onto sense key, asc & ascq.
1007 	 */
1008 	if (qc->err_mask ||
1009 	    tf->command & (ATA_BUSY | ATA_DF | ATA_ERR | ATA_DRQ)) {
1010 		ata_to_sense_error(qc->ap->print_id, tf->command, tf->feature,
1011 				   &sb[1], &sb[2], &sb[3], verbose);
1012 		sb[1] &= 0x0f;
1013 	} else {
1014 		sb[1] = RECOVERED_ERROR;
1015 		sb[2] = 0;
1016 		sb[3] = 0x1D;
1017 	}
1018 
1019 	/*
1020 	 * Sense data is current and format is descriptor.
1021 	 */
1022 	sb[0] = 0x72;
1023 
1024 	desc[0] = 0x09;
1025 
1026 	/* set length of additional sense data */
1027 	sb[7] = 14;
1028 	desc[1] = 12;
1029 
1030 	/*
1031 	 * Copy registers into sense buffer.
1032 	 */
1033 	desc[2] = 0x00;
1034 	desc[3] = tf->feature;	/* == error reg */
1035 	desc[5] = tf->nsect;
1036 	desc[7] = tf->lbal;
1037 	desc[9] = tf->lbam;
1038 	desc[11] = tf->lbah;
1039 	desc[12] = tf->device;
1040 	desc[13] = tf->command; /* == status reg */
1041 
1042 	/*
1043 	 * Fill in Extend bit, and the high order bytes
1044 	 * if applicable.
1045 	 */
1046 	if (tf->flags & ATA_TFLAG_LBA48) {
1047 		desc[2] |= 0x01;
1048 		desc[4] = tf->hob_nsect;
1049 		desc[6] = tf->hob_lbal;
1050 		desc[8] = tf->hob_lbam;
1051 		desc[10] = tf->hob_lbah;
1052 	}
1053 }
1054 
1055 /**
1056  *	ata_gen_ata_sense - generate a SCSI fixed sense block
1057  *	@qc: Command that we are erroring out
1058  *
1059  *	Generate sense block for a failed ATA command @qc.  Descriptor
1060  *	format is used to accommodate LBA48 block address.
1061  *
1062  *	LOCKING:
1063  *	None.
1064  */
1065 static void ata_gen_ata_sense(struct ata_queued_cmd *qc)
1066 {
1067 	struct ata_device *dev = qc->dev;
1068 	struct scsi_cmnd *cmd = qc->scsicmd;
1069 	struct ata_taskfile *tf = &qc->result_tf;
1070 	unsigned char *sb = cmd->sense_buffer;
1071 	unsigned char *desc = sb + 8;
1072 	int verbose = qc->ap->ops->error_handler == NULL;
1073 	u64 block;
1074 
1075 	memset(sb, 0, SCSI_SENSE_BUFFERSIZE);
1076 
1077 	cmd->result = (DRIVER_SENSE << 24) | SAM_STAT_CHECK_CONDITION;
1078 
1079 	/* sense data is current and format is descriptor */
1080 	sb[0] = 0x72;
1081 
1082 	/* Use ata_to_sense_error() to map status register bits
1083 	 * onto sense key, asc & ascq.
1084 	 */
1085 	if (qc->err_mask ||
1086 	    tf->command & (ATA_BUSY | ATA_DF | ATA_ERR | ATA_DRQ)) {
1087 		ata_to_sense_error(qc->ap->print_id, tf->command, tf->feature,
1088 				   &sb[1], &sb[2], &sb[3], verbose);
1089 		sb[1] &= 0x0f;
1090 	}
1091 
1092 	block = ata_tf_read_block(&qc->result_tf, dev);
1093 
1094 	/* information sense data descriptor */
1095 	sb[7] = 12;
1096 	desc[0] = 0x00;
1097 	desc[1] = 10;
1098 
1099 	desc[2] |= 0x80;	/* valid */
1100 	desc[6] = block >> 40;
1101 	desc[7] = block >> 32;
1102 	desc[8] = block >> 24;
1103 	desc[9] = block >> 16;
1104 	desc[10] = block >> 8;
1105 	desc[11] = block;
1106 }
1107 
1108 static void ata_scsi_sdev_config(struct scsi_device *sdev)
1109 {
1110 	sdev->use_10_for_rw = 1;
1111 	sdev->use_10_for_ms = 1;
1112 	sdev->no_report_opcodes = 1;
1113 	sdev->no_write_same = 1;
1114 
1115 	/* Schedule policy is determined by ->qc_defer() callback and
1116 	 * it needs to see every deferred qc.  Set dev_blocked to 1 to
1117 	 * prevent SCSI midlayer from automatically deferring
1118 	 * requests.
1119 	 */
1120 	sdev->max_device_blocked = 1;
1121 }
1122 
1123 /**
1124  *	atapi_drain_needed - Check whether data transfer may overflow
1125  *	@rq: request to be checked
1126  *
1127  *	ATAPI commands which transfer variable length data to host
1128  *	might overflow due to application error or hardare bug.  This
1129  *	function checks whether overflow should be drained and ignored
1130  *	for @request.
1131  *
1132  *	LOCKING:
1133  *	None.
1134  *
1135  *	RETURNS:
1136  *	1 if ; otherwise, 0.
1137  */
1138 static int atapi_drain_needed(struct request *rq)
1139 {
1140 	if (likely(rq->cmd_type != REQ_TYPE_BLOCK_PC))
1141 		return 0;
1142 
1143 	if (!blk_rq_bytes(rq) || (rq->cmd_flags & REQ_WRITE))
1144 		return 0;
1145 
1146 	return atapi_cmd_type(rq->cmd[0]) == ATAPI_MISC;
1147 }
1148 
1149 static int ata_scsi_dev_config(struct scsi_device *sdev,
1150 			       struct ata_device *dev)
1151 {
1152 	struct request_queue *q = sdev->request_queue;
1153 
1154 	if (!ata_id_has_unload(dev->id))
1155 		dev->flags |= ATA_DFLAG_NO_UNLOAD;
1156 
1157 	/* configure max sectors */
1158 	blk_queue_max_hw_sectors(q, dev->max_sectors);
1159 
1160 	if (dev->class == ATA_DEV_ATAPI) {
1161 		void *buf;
1162 
1163 		sdev->sector_size = ATA_SECT_SIZE;
1164 
1165 		/* set DMA padding */
1166 		blk_queue_update_dma_pad(q, ATA_DMA_PAD_SZ - 1);
1167 
1168 		/* configure draining */
1169 		buf = kmalloc(ATAPI_MAX_DRAIN, q->bounce_gfp | GFP_KERNEL);
1170 		if (!buf) {
1171 			ata_dev_err(dev, "drain buffer allocation failed\n");
1172 			return -ENOMEM;
1173 		}
1174 
1175 		blk_queue_dma_drain(q, atapi_drain_needed, buf, ATAPI_MAX_DRAIN);
1176 	} else {
1177 		sdev->sector_size = ata_id_logical_sector_size(dev->id);
1178 		sdev->manage_start_stop = 1;
1179 	}
1180 
1181 	/*
1182 	 * ata_pio_sectors() expects buffer for each sector to not cross
1183 	 * page boundary.  Enforce it by requiring buffers to be sector
1184 	 * aligned, which works iff sector_size is not larger than
1185 	 * PAGE_SIZE.  ATAPI devices also need the alignment as
1186 	 * IDENTIFY_PACKET is executed as ATA_PROT_PIO.
1187 	 */
1188 	if (sdev->sector_size > PAGE_SIZE)
1189 		ata_dev_warn(dev,
1190 			"sector_size=%u > PAGE_SIZE, PIO may malfunction\n",
1191 			sdev->sector_size);
1192 
1193 	blk_queue_update_dma_alignment(q, sdev->sector_size - 1);
1194 
1195 	if (dev->flags & ATA_DFLAG_AN)
1196 		set_bit(SDEV_EVT_MEDIA_CHANGE, sdev->supported_events);
1197 
1198 	if (dev->flags & ATA_DFLAG_NCQ) {
1199 		int depth;
1200 
1201 		depth = min(sdev->host->can_queue, ata_id_queue_depth(dev->id));
1202 		depth = min(ATA_MAX_QUEUE - 1, depth);
1203 		scsi_change_queue_depth(sdev, depth);
1204 	}
1205 
1206 	blk_queue_flush_queueable(q, false);
1207 
1208 	dev->sdev = sdev;
1209 	return 0;
1210 }
1211 
1212 /**
1213  *	ata_scsi_slave_config - Set SCSI device attributes
1214  *	@sdev: SCSI device to examine
1215  *
1216  *	This is called before we actually start reading
1217  *	and writing to the device, to configure certain
1218  *	SCSI mid-layer behaviors.
1219  *
1220  *	LOCKING:
1221  *	Defined by SCSI layer.  We don't really care.
1222  */
1223 
1224 int ata_scsi_slave_config(struct scsi_device *sdev)
1225 {
1226 	struct ata_port *ap = ata_shost_to_port(sdev->host);
1227 	struct ata_device *dev = __ata_scsi_find_dev(ap, sdev);
1228 	int rc = 0;
1229 
1230 	ata_scsi_sdev_config(sdev);
1231 
1232 	if (dev)
1233 		rc = ata_scsi_dev_config(sdev, dev);
1234 
1235 	return rc;
1236 }
1237 
1238 /**
1239  *	ata_scsi_slave_destroy - SCSI device is about to be destroyed
1240  *	@sdev: SCSI device to be destroyed
1241  *
1242  *	@sdev is about to be destroyed for hot/warm unplugging.  If
1243  *	this unplugging was initiated by libata as indicated by NULL
1244  *	dev->sdev, this function doesn't have to do anything.
1245  *	Otherwise, SCSI layer initiated warm-unplug is in progress.
1246  *	Clear dev->sdev, schedule the device for ATA detach and invoke
1247  *	EH.
1248  *
1249  *	LOCKING:
1250  *	Defined by SCSI layer.  We don't really care.
1251  */
1252 void ata_scsi_slave_destroy(struct scsi_device *sdev)
1253 {
1254 	struct ata_port *ap = ata_shost_to_port(sdev->host);
1255 	struct request_queue *q = sdev->request_queue;
1256 	unsigned long flags;
1257 	struct ata_device *dev;
1258 
1259 	if (!ap->ops->error_handler)
1260 		return;
1261 
1262 	spin_lock_irqsave(ap->lock, flags);
1263 	dev = __ata_scsi_find_dev(ap, sdev);
1264 	if (dev && dev->sdev) {
1265 		/* SCSI device already in CANCEL state, no need to offline it */
1266 		dev->sdev = NULL;
1267 		dev->flags |= ATA_DFLAG_DETACH;
1268 		ata_port_schedule_eh(ap);
1269 	}
1270 	spin_unlock_irqrestore(ap->lock, flags);
1271 
1272 	kfree(q->dma_drain_buffer);
1273 	q->dma_drain_buffer = NULL;
1274 	q->dma_drain_size = 0;
1275 }
1276 
1277 /**
1278  *	__ata_change_queue_depth - helper for ata_scsi_change_queue_depth
1279  *	@ap: ATA port to which the device change the queue depth
1280  *	@sdev: SCSI device to configure queue depth for
1281  *	@queue_depth: new queue depth
1282  *
1283  *	libsas and libata have different approaches for associating a sdev to
1284  *	its ata_port.
1285  *
1286  */
1287 int __ata_change_queue_depth(struct ata_port *ap, struct scsi_device *sdev,
1288 			     int queue_depth)
1289 {
1290 	struct ata_device *dev;
1291 	unsigned long flags;
1292 
1293 	if (queue_depth < 1 || queue_depth == sdev->queue_depth)
1294 		return sdev->queue_depth;
1295 
1296 	dev = ata_scsi_find_dev(ap, sdev);
1297 	if (!dev || !ata_dev_enabled(dev))
1298 		return sdev->queue_depth;
1299 
1300 	/* NCQ enabled? */
1301 	spin_lock_irqsave(ap->lock, flags);
1302 	dev->flags &= ~ATA_DFLAG_NCQ_OFF;
1303 	if (queue_depth == 1 || !ata_ncq_enabled(dev)) {
1304 		dev->flags |= ATA_DFLAG_NCQ_OFF;
1305 		queue_depth = 1;
1306 	}
1307 	spin_unlock_irqrestore(ap->lock, flags);
1308 
1309 	/* limit and apply queue depth */
1310 	queue_depth = min(queue_depth, sdev->host->can_queue);
1311 	queue_depth = min(queue_depth, ata_id_queue_depth(dev->id));
1312 	queue_depth = min(queue_depth, ATA_MAX_QUEUE - 1);
1313 
1314 	if (sdev->queue_depth == queue_depth)
1315 		return -EINVAL;
1316 
1317 	return scsi_change_queue_depth(sdev, queue_depth);
1318 }
1319 
1320 /**
1321  *	ata_scsi_change_queue_depth - SCSI callback for queue depth config
1322  *	@sdev: SCSI device to configure queue depth for
1323  *	@queue_depth: new queue depth
1324  *
1325  *	This is libata standard hostt->change_queue_depth callback.
1326  *	SCSI will call into this callback when user tries to set queue
1327  *	depth via sysfs.
1328  *
1329  *	LOCKING:
1330  *	SCSI layer (we don't care)
1331  *
1332  *	RETURNS:
1333  *	Newly configured queue depth.
1334  */
1335 int ata_scsi_change_queue_depth(struct scsi_device *sdev, int queue_depth)
1336 {
1337 	struct ata_port *ap = ata_shost_to_port(sdev->host);
1338 
1339 	return __ata_change_queue_depth(ap, sdev, queue_depth);
1340 }
1341 
1342 /**
1343  *	ata_scsi_start_stop_xlat - Translate SCSI START STOP UNIT command
1344  *	@qc: Storage for translated ATA taskfile
1345  *
1346  *	Sets up an ATA taskfile to issue STANDBY (to stop) or READ VERIFY
1347  *	(to start). Perhaps these commands should be preceded by
1348  *	CHECK POWER MODE to see what power mode the device is already in.
1349  *	[See SAT revision 5 at www.t10.org]
1350  *
1351  *	LOCKING:
1352  *	spin_lock_irqsave(host lock)
1353  *
1354  *	RETURNS:
1355  *	Zero on success, non-zero on error.
1356  */
1357 static unsigned int ata_scsi_start_stop_xlat(struct ata_queued_cmd *qc)
1358 {
1359 	struct scsi_cmnd *scmd = qc->scsicmd;
1360 	struct ata_taskfile *tf = &qc->tf;
1361 	const u8 *cdb = scmd->cmnd;
1362 
1363 	if (scmd->cmd_len < 5)
1364 		goto invalid_fld;
1365 
1366 	tf->flags |= ATA_TFLAG_DEVICE | ATA_TFLAG_ISADDR;
1367 	tf->protocol = ATA_PROT_NODATA;
1368 	if (cdb[1] & 0x1) {
1369 		;	/* ignore IMMED bit, violates sat-r05 */
1370 	}
1371 	if (cdb[4] & 0x2)
1372 		goto invalid_fld;       /* LOEJ bit set not supported */
1373 	if (((cdb[4] >> 4) & 0xf) != 0)
1374 		goto invalid_fld;       /* power conditions not supported */
1375 
1376 	if (cdb[4] & 0x1) {
1377 		tf->nsect = 1;	/* 1 sector, lba=0 */
1378 
1379 		if (qc->dev->flags & ATA_DFLAG_LBA) {
1380 			tf->flags |= ATA_TFLAG_LBA;
1381 
1382 			tf->lbah = 0x0;
1383 			tf->lbam = 0x0;
1384 			tf->lbal = 0x0;
1385 			tf->device |= ATA_LBA;
1386 		} else {
1387 			/* CHS */
1388 			tf->lbal = 0x1; /* sect */
1389 			tf->lbam = 0x0; /* cyl low */
1390 			tf->lbah = 0x0; /* cyl high */
1391 		}
1392 
1393 		tf->command = ATA_CMD_VERIFY;	/* READ VERIFY */
1394 	} else {
1395 		/* Some odd clown BIOSen issue spindown on power off (ACPI S4
1396 		 * or S5) causing some drives to spin up and down again.
1397 		 */
1398 		if ((qc->ap->flags & ATA_FLAG_NO_POWEROFF_SPINDOWN) &&
1399 		    system_state == SYSTEM_POWER_OFF)
1400 			goto skip;
1401 
1402 		if ((qc->ap->flags & ATA_FLAG_NO_HIBERNATE_SPINDOWN) &&
1403 		     system_entering_hibernation())
1404 			goto skip;
1405 
1406 		/* Issue ATA STANDBY IMMEDIATE command */
1407 		tf->command = ATA_CMD_STANDBYNOW1;
1408 	}
1409 
1410 	/*
1411 	 * Standby and Idle condition timers could be implemented but that
1412 	 * would require libata to implement the Power condition mode page
1413 	 * and allow the user to change it. Changing mode pages requires
1414 	 * MODE SELECT to be implemented.
1415 	 */
1416 
1417 	return 0;
1418 
1419  invalid_fld:
1420 	ata_scsi_set_sense(scmd, ILLEGAL_REQUEST, 0x24, 0x0);
1421 	/* "Invalid field in cbd" */
1422 	return 1;
1423  skip:
1424 	scmd->result = SAM_STAT_GOOD;
1425 	return 1;
1426 }
1427 
1428 
1429 /**
1430  *	ata_scsi_flush_xlat - Translate SCSI SYNCHRONIZE CACHE command
1431  *	@qc: Storage for translated ATA taskfile
1432  *
1433  *	Sets up an ATA taskfile to issue FLUSH CACHE or
1434  *	FLUSH CACHE EXT.
1435  *
1436  *	LOCKING:
1437  *	spin_lock_irqsave(host lock)
1438  *
1439  *	RETURNS:
1440  *	Zero on success, non-zero on error.
1441  */
1442 static unsigned int ata_scsi_flush_xlat(struct ata_queued_cmd *qc)
1443 {
1444 	struct ata_taskfile *tf = &qc->tf;
1445 
1446 	tf->flags |= ATA_TFLAG_DEVICE;
1447 	tf->protocol = ATA_PROT_NODATA;
1448 
1449 	if (qc->dev->flags & ATA_DFLAG_FLUSH_EXT)
1450 		tf->command = ATA_CMD_FLUSH_EXT;
1451 	else
1452 		tf->command = ATA_CMD_FLUSH;
1453 
1454 	/* flush is critical for IO integrity, consider it an IO command */
1455 	qc->flags |= ATA_QCFLAG_IO;
1456 
1457 	return 0;
1458 }
1459 
1460 /**
1461  *	scsi_6_lba_len - Get LBA and transfer length
1462  *	@cdb: SCSI command to translate
1463  *
1464  *	Calculate LBA and transfer length for 6-byte commands.
1465  *
1466  *	RETURNS:
1467  *	@plba: the LBA
1468  *	@plen: the transfer length
1469  */
1470 static void scsi_6_lba_len(const u8 *cdb, u64 *plba, u32 *plen)
1471 {
1472 	u64 lba = 0;
1473 	u32 len;
1474 
1475 	VPRINTK("six-byte command\n");
1476 
1477 	lba |= ((u64)(cdb[1] & 0x1f)) << 16;
1478 	lba |= ((u64)cdb[2]) << 8;
1479 	lba |= ((u64)cdb[3]);
1480 
1481 	len = cdb[4];
1482 
1483 	*plba = lba;
1484 	*plen = len;
1485 }
1486 
1487 /**
1488  *	scsi_10_lba_len - Get LBA and transfer length
1489  *	@cdb: SCSI command to translate
1490  *
1491  *	Calculate LBA and transfer length for 10-byte commands.
1492  *
1493  *	RETURNS:
1494  *	@plba: the LBA
1495  *	@plen: the transfer length
1496  */
1497 static void scsi_10_lba_len(const u8 *cdb, u64 *plba, u32 *plen)
1498 {
1499 	u64 lba = 0;
1500 	u32 len = 0;
1501 
1502 	VPRINTK("ten-byte command\n");
1503 
1504 	lba |= ((u64)cdb[2]) << 24;
1505 	lba |= ((u64)cdb[3]) << 16;
1506 	lba |= ((u64)cdb[4]) << 8;
1507 	lba |= ((u64)cdb[5]);
1508 
1509 	len |= ((u32)cdb[7]) << 8;
1510 	len |= ((u32)cdb[8]);
1511 
1512 	*plba = lba;
1513 	*plen = len;
1514 }
1515 
1516 /**
1517  *	scsi_16_lba_len - Get LBA and transfer length
1518  *	@cdb: SCSI command to translate
1519  *
1520  *	Calculate LBA and transfer length for 16-byte commands.
1521  *
1522  *	RETURNS:
1523  *	@plba: the LBA
1524  *	@plen: the transfer length
1525  */
1526 static void scsi_16_lba_len(const u8 *cdb, u64 *plba, u32 *plen)
1527 {
1528 	u64 lba = 0;
1529 	u32 len = 0;
1530 
1531 	VPRINTK("sixteen-byte command\n");
1532 
1533 	lba |= ((u64)cdb[2]) << 56;
1534 	lba |= ((u64)cdb[3]) << 48;
1535 	lba |= ((u64)cdb[4]) << 40;
1536 	lba |= ((u64)cdb[5]) << 32;
1537 	lba |= ((u64)cdb[6]) << 24;
1538 	lba |= ((u64)cdb[7]) << 16;
1539 	lba |= ((u64)cdb[8]) << 8;
1540 	lba |= ((u64)cdb[9]);
1541 
1542 	len |= ((u32)cdb[10]) << 24;
1543 	len |= ((u32)cdb[11]) << 16;
1544 	len |= ((u32)cdb[12]) << 8;
1545 	len |= ((u32)cdb[13]);
1546 
1547 	*plba = lba;
1548 	*plen = len;
1549 }
1550 
1551 /**
1552  *	ata_scsi_verify_xlat - Translate SCSI VERIFY command into an ATA one
1553  *	@qc: Storage for translated ATA taskfile
1554  *
1555  *	Converts SCSI VERIFY command to an ATA READ VERIFY command.
1556  *
1557  *	LOCKING:
1558  *	spin_lock_irqsave(host lock)
1559  *
1560  *	RETURNS:
1561  *	Zero on success, non-zero on error.
1562  */
1563 static unsigned int ata_scsi_verify_xlat(struct ata_queued_cmd *qc)
1564 {
1565 	struct scsi_cmnd *scmd = qc->scsicmd;
1566 	struct ata_taskfile *tf = &qc->tf;
1567 	struct ata_device *dev = qc->dev;
1568 	u64 dev_sectors = qc->dev->n_sectors;
1569 	const u8 *cdb = scmd->cmnd;
1570 	u64 block;
1571 	u32 n_block;
1572 
1573 	tf->flags |= ATA_TFLAG_ISADDR | ATA_TFLAG_DEVICE;
1574 	tf->protocol = ATA_PROT_NODATA;
1575 
1576 	if (cdb[0] == VERIFY) {
1577 		if (scmd->cmd_len < 10)
1578 			goto invalid_fld;
1579 		scsi_10_lba_len(cdb, &block, &n_block);
1580 	} else if (cdb[0] == VERIFY_16) {
1581 		if (scmd->cmd_len < 16)
1582 			goto invalid_fld;
1583 		scsi_16_lba_len(cdb, &block, &n_block);
1584 	} else
1585 		goto invalid_fld;
1586 
1587 	if (!n_block)
1588 		goto nothing_to_do;
1589 	if (block >= dev_sectors)
1590 		goto out_of_range;
1591 	if ((block + n_block) > dev_sectors)
1592 		goto out_of_range;
1593 
1594 	if (dev->flags & ATA_DFLAG_LBA) {
1595 		tf->flags |= ATA_TFLAG_LBA;
1596 
1597 		if (lba_28_ok(block, n_block)) {
1598 			/* use LBA28 */
1599 			tf->command = ATA_CMD_VERIFY;
1600 			tf->device |= (block >> 24) & 0xf;
1601 		} else if (lba_48_ok(block, n_block)) {
1602 			if (!(dev->flags & ATA_DFLAG_LBA48))
1603 				goto out_of_range;
1604 
1605 			/* use LBA48 */
1606 			tf->flags |= ATA_TFLAG_LBA48;
1607 			tf->command = ATA_CMD_VERIFY_EXT;
1608 
1609 			tf->hob_nsect = (n_block >> 8) & 0xff;
1610 
1611 			tf->hob_lbah = (block >> 40) & 0xff;
1612 			tf->hob_lbam = (block >> 32) & 0xff;
1613 			tf->hob_lbal = (block >> 24) & 0xff;
1614 		} else
1615 			/* request too large even for LBA48 */
1616 			goto out_of_range;
1617 
1618 		tf->nsect = n_block & 0xff;
1619 
1620 		tf->lbah = (block >> 16) & 0xff;
1621 		tf->lbam = (block >> 8) & 0xff;
1622 		tf->lbal = block & 0xff;
1623 
1624 		tf->device |= ATA_LBA;
1625 	} else {
1626 		/* CHS */
1627 		u32 sect, head, cyl, track;
1628 
1629 		if (!lba_28_ok(block, n_block))
1630 			goto out_of_range;
1631 
1632 		/* Convert LBA to CHS */
1633 		track = (u32)block / dev->sectors;
1634 		cyl   = track / dev->heads;
1635 		head  = track % dev->heads;
1636 		sect  = (u32)block % dev->sectors + 1;
1637 
1638 		DPRINTK("block %u track %u cyl %u head %u sect %u\n",
1639 			(u32)block, track, cyl, head, sect);
1640 
1641 		/* Check whether the converted CHS can fit.
1642 		   Cylinder: 0-65535
1643 		   Head: 0-15
1644 		   Sector: 1-255*/
1645 		if ((cyl >> 16) || (head >> 4) || (sect >> 8) || (!sect))
1646 			goto out_of_range;
1647 
1648 		tf->command = ATA_CMD_VERIFY;
1649 		tf->nsect = n_block & 0xff; /* Sector count 0 means 256 sectors */
1650 		tf->lbal = sect;
1651 		tf->lbam = cyl;
1652 		tf->lbah = cyl >> 8;
1653 		tf->device |= head;
1654 	}
1655 
1656 	return 0;
1657 
1658 invalid_fld:
1659 	ata_scsi_set_sense(scmd, ILLEGAL_REQUEST, 0x24, 0x0);
1660 	/* "Invalid field in cbd" */
1661 	return 1;
1662 
1663 out_of_range:
1664 	ata_scsi_set_sense(scmd, ILLEGAL_REQUEST, 0x21, 0x0);
1665 	/* "Logical Block Address out of range" */
1666 	return 1;
1667 
1668 nothing_to_do:
1669 	scmd->result = SAM_STAT_GOOD;
1670 	return 1;
1671 }
1672 
1673 /**
1674  *	ata_scsi_rw_xlat - Translate SCSI r/w command into an ATA one
1675  *	@qc: Storage for translated ATA taskfile
1676  *
1677  *	Converts any of six SCSI read/write commands into the
1678  *	ATA counterpart, including starting sector (LBA),
1679  *	sector count, and taking into account the device's LBA48
1680  *	support.
1681  *
1682  *	Commands %READ_6, %READ_10, %READ_16, %WRITE_6, %WRITE_10, and
1683  *	%WRITE_16 are currently supported.
1684  *
1685  *	LOCKING:
1686  *	spin_lock_irqsave(host lock)
1687  *
1688  *	RETURNS:
1689  *	Zero on success, non-zero on error.
1690  */
1691 static unsigned int ata_scsi_rw_xlat(struct ata_queued_cmd *qc)
1692 {
1693 	struct scsi_cmnd *scmd = qc->scsicmd;
1694 	const u8 *cdb = scmd->cmnd;
1695 	unsigned int tf_flags = 0;
1696 	u64 block;
1697 	u32 n_block;
1698 	int rc;
1699 
1700 	if (cdb[0] == WRITE_10 || cdb[0] == WRITE_6 || cdb[0] == WRITE_16)
1701 		tf_flags |= ATA_TFLAG_WRITE;
1702 
1703 	/* Calculate the SCSI LBA, transfer length and FUA. */
1704 	switch (cdb[0]) {
1705 	case READ_10:
1706 	case WRITE_10:
1707 		if (unlikely(scmd->cmd_len < 10))
1708 			goto invalid_fld;
1709 		scsi_10_lba_len(cdb, &block, &n_block);
1710 		if (cdb[1] & (1 << 3))
1711 			tf_flags |= ATA_TFLAG_FUA;
1712 		break;
1713 	case READ_6:
1714 	case WRITE_6:
1715 		if (unlikely(scmd->cmd_len < 6))
1716 			goto invalid_fld;
1717 		scsi_6_lba_len(cdb, &block, &n_block);
1718 
1719 		/* for 6-byte r/w commands, transfer length 0
1720 		 * means 256 blocks of data, not 0 block.
1721 		 */
1722 		if (!n_block)
1723 			n_block = 256;
1724 		break;
1725 	case READ_16:
1726 	case WRITE_16:
1727 		if (unlikely(scmd->cmd_len < 16))
1728 			goto invalid_fld;
1729 		scsi_16_lba_len(cdb, &block, &n_block);
1730 		if (cdb[1] & (1 << 3))
1731 			tf_flags |= ATA_TFLAG_FUA;
1732 		break;
1733 	default:
1734 		DPRINTK("no-byte command\n");
1735 		goto invalid_fld;
1736 	}
1737 
1738 	/* Check and compose ATA command */
1739 	if (!n_block)
1740 		/* For 10-byte and 16-byte SCSI R/W commands, transfer
1741 		 * length 0 means transfer 0 block of data.
1742 		 * However, for ATA R/W commands, sector count 0 means
1743 		 * 256 or 65536 sectors, not 0 sectors as in SCSI.
1744 		 *
1745 		 * WARNING: one or two older ATA drives treat 0 as 0...
1746 		 */
1747 		goto nothing_to_do;
1748 
1749 	qc->flags |= ATA_QCFLAG_IO;
1750 	qc->nbytes = n_block * scmd->device->sector_size;
1751 
1752 	rc = ata_build_rw_tf(&qc->tf, qc->dev, block, n_block, tf_flags,
1753 			     qc->tag);
1754 	if (likely(rc == 0))
1755 		return 0;
1756 
1757 	if (rc == -ERANGE)
1758 		goto out_of_range;
1759 	/* treat all other errors as -EINVAL, fall through */
1760 invalid_fld:
1761 	ata_scsi_set_sense(scmd, ILLEGAL_REQUEST, 0x24, 0x0);
1762 	/* "Invalid field in cbd" */
1763 	return 1;
1764 
1765 out_of_range:
1766 	ata_scsi_set_sense(scmd, ILLEGAL_REQUEST, 0x21, 0x0);
1767 	/* "Logical Block Address out of range" */
1768 	return 1;
1769 
1770 nothing_to_do:
1771 	scmd->result = SAM_STAT_GOOD;
1772 	return 1;
1773 }
1774 
1775 static void ata_scsi_qc_complete(struct ata_queued_cmd *qc)
1776 {
1777 	struct ata_port *ap = qc->ap;
1778 	struct scsi_cmnd *cmd = qc->scsicmd;
1779 	u8 *cdb = cmd->cmnd;
1780 	int need_sense = (qc->err_mask != 0);
1781 
1782 	/* For ATA pass thru (SAT) commands, generate a sense block if
1783 	 * user mandated it or if there's an error.  Note that if we
1784 	 * generate because the user forced us to [CK_COND =1], a check
1785 	 * condition is generated and the ATA register values are returned
1786 	 * whether the command completed successfully or not. If there
1787 	 * was no error, we use the following sense data:
1788 	 * sk = RECOVERED ERROR
1789 	 * asc,ascq = ATA PASS-THROUGH INFORMATION AVAILABLE
1790 	 */
1791 	if (((cdb[0] == ATA_16) || (cdb[0] == ATA_12)) &&
1792 	    ((cdb[2] & 0x20) || need_sense)) {
1793 		ata_gen_passthru_sense(qc);
1794 	} else {
1795 		if (qc->flags & ATA_QCFLAG_SENSE_VALID) {
1796 			cmd->result = SAM_STAT_CHECK_CONDITION;
1797 		} else if (!need_sense) {
1798 			cmd->result = SAM_STAT_GOOD;
1799 		} else {
1800 			/* TODO: decide which descriptor format to use
1801 			 * for 48b LBA devices and call that here
1802 			 * instead of the fixed desc, which is only
1803 			 * good for smaller LBA (and maybe CHS?)
1804 			 * devices.
1805 			 */
1806 			ata_gen_ata_sense(qc);
1807 		}
1808 	}
1809 
1810 	if (need_sense && !ap->ops->error_handler)
1811 		ata_dump_status(ap->print_id, &qc->result_tf);
1812 
1813 	qc->scsidone(cmd);
1814 
1815 	ata_qc_free(qc);
1816 }
1817 
1818 /**
1819  *	ata_scsi_translate - Translate then issue SCSI command to ATA device
1820  *	@dev: ATA device to which the command is addressed
1821  *	@cmd: SCSI command to execute
1822  *	@xlat_func: Actor which translates @cmd to an ATA taskfile
1823  *
1824  *	Our ->queuecommand() function has decided that the SCSI
1825  *	command issued can be directly translated into an ATA
1826  *	command, rather than handled internally.
1827  *
1828  *	This function sets up an ata_queued_cmd structure for the
1829  *	SCSI command, and sends that ata_queued_cmd to the hardware.
1830  *
1831  *	The xlat_func argument (actor) returns 0 if ready to execute
1832  *	ATA command, else 1 to finish translation. If 1 is returned
1833  *	then cmd->result (and possibly cmd->sense_buffer) are assumed
1834  *	to be set reflecting an error condition or clean (early)
1835  *	termination.
1836  *
1837  *	LOCKING:
1838  *	spin_lock_irqsave(host lock)
1839  *
1840  *	RETURNS:
1841  *	0 on success, SCSI_ML_QUEUE_DEVICE_BUSY if the command
1842  *	needs to be deferred.
1843  */
1844 static int ata_scsi_translate(struct ata_device *dev, struct scsi_cmnd *cmd,
1845 			      ata_xlat_func_t xlat_func)
1846 {
1847 	struct ata_port *ap = dev->link->ap;
1848 	struct ata_queued_cmd *qc;
1849 	int rc;
1850 
1851 	VPRINTK("ENTER\n");
1852 
1853 	qc = ata_scsi_qc_new(dev, cmd);
1854 	if (!qc)
1855 		goto err_mem;
1856 
1857 	/* data is present; dma-map it */
1858 	if (cmd->sc_data_direction == DMA_FROM_DEVICE ||
1859 	    cmd->sc_data_direction == DMA_TO_DEVICE) {
1860 		if (unlikely(scsi_bufflen(cmd) < 1)) {
1861 			ata_dev_warn(dev, "WARNING: zero len r/w req\n");
1862 			goto err_did;
1863 		}
1864 
1865 		ata_sg_init(qc, scsi_sglist(cmd), scsi_sg_count(cmd));
1866 
1867 		qc->dma_dir = cmd->sc_data_direction;
1868 	}
1869 
1870 	qc->complete_fn = ata_scsi_qc_complete;
1871 
1872 	if (xlat_func(qc))
1873 		goto early_finish;
1874 
1875 	if (ap->ops->qc_defer) {
1876 		if ((rc = ap->ops->qc_defer(qc)))
1877 			goto defer;
1878 	}
1879 
1880 	/* select device, send command to hardware */
1881 	ata_qc_issue(qc);
1882 
1883 	VPRINTK("EXIT\n");
1884 	return 0;
1885 
1886 early_finish:
1887 	ata_qc_free(qc);
1888 	cmd->scsi_done(cmd);
1889 	DPRINTK("EXIT - early finish (good or error)\n");
1890 	return 0;
1891 
1892 err_did:
1893 	ata_qc_free(qc);
1894 	cmd->result = (DID_ERROR << 16);
1895 	cmd->scsi_done(cmd);
1896 err_mem:
1897 	DPRINTK("EXIT - internal\n");
1898 	return 0;
1899 
1900 defer:
1901 	ata_qc_free(qc);
1902 	DPRINTK("EXIT - defer\n");
1903 	if (rc == ATA_DEFER_LINK)
1904 		return SCSI_MLQUEUE_DEVICE_BUSY;
1905 	else
1906 		return SCSI_MLQUEUE_HOST_BUSY;
1907 }
1908 
1909 /**
1910  *	ata_scsi_rbuf_get - Map response buffer.
1911  *	@cmd: SCSI command containing buffer to be mapped.
1912  *	@flags: unsigned long variable to store irq enable status
1913  *	@copy_in: copy in from user buffer
1914  *
1915  *	Prepare buffer for simulated SCSI commands.
1916  *
1917  *	LOCKING:
1918  *	spin_lock_irqsave(ata_scsi_rbuf_lock) on success
1919  *
1920  *	RETURNS:
1921  *	Pointer to response buffer.
1922  */
1923 static void *ata_scsi_rbuf_get(struct scsi_cmnd *cmd, bool copy_in,
1924 			       unsigned long *flags)
1925 {
1926 	spin_lock_irqsave(&ata_scsi_rbuf_lock, *flags);
1927 
1928 	memset(ata_scsi_rbuf, 0, ATA_SCSI_RBUF_SIZE);
1929 	if (copy_in)
1930 		sg_copy_to_buffer(scsi_sglist(cmd), scsi_sg_count(cmd),
1931 				  ata_scsi_rbuf, ATA_SCSI_RBUF_SIZE);
1932 	return ata_scsi_rbuf;
1933 }
1934 
1935 /**
1936  *	ata_scsi_rbuf_put - Unmap response buffer.
1937  *	@cmd: SCSI command containing buffer to be unmapped.
1938  *	@copy_out: copy out result
1939  *	@flags: @flags passed to ata_scsi_rbuf_get()
1940  *
1941  *	Returns rbuf buffer.  The result is copied to @cmd's buffer if
1942  *	@copy_back is true.
1943  *
1944  *	LOCKING:
1945  *	Unlocks ata_scsi_rbuf_lock.
1946  */
1947 static inline void ata_scsi_rbuf_put(struct scsi_cmnd *cmd, bool copy_out,
1948 				     unsigned long *flags)
1949 {
1950 	if (copy_out)
1951 		sg_copy_from_buffer(scsi_sglist(cmd), scsi_sg_count(cmd),
1952 				    ata_scsi_rbuf, ATA_SCSI_RBUF_SIZE);
1953 	spin_unlock_irqrestore(&ata_scsi_rbuf_lock, *flags);
1954 }
1955 
1956 /**
1957  *	ata_scsi_rbuf_fill - wrapper for SCSI command simulators
1958  *	@args: device IDENTIFY data / SCSI command of interest.
1959  *	@actor: Callback hook for desired SCSI command simulator
1960  *
1961  *	Takes care of the hard work of simulating a SCSI command...
1962  *	Mapping the response buffer, calling the command's handler,
1963  *	and handling the handler's return value.  This return value
1964  *	indicates whether the handler wishes the SCSI command to be
1965  *	completed successfully (0), or not (in which case cmd->result
1966  *	and sense buffer are assumed to be set).
1967  *
1968  *	LOCKING:
1969  *	spin_lock_irqsave(host lock)
1970  */
1971 static void ata_scsi_rbuf_fill(struct ata_scsi_args *args,
1972 		unsigned int (*actor)(struct ata_scsi_args *args, u8 *rbuf))
1973 {
1974 	u8 *rbuf;
1975 	unsigned int rc;
1976 	struct scsi_cmnd *cmd = args->cmd;
1977 	unsigned long flags;
1978 
1979 	rbuf = ata_scsi_rbuf_get(cmd, false, &flags);
1980 	rc = actor(args, rbuf);
1981 	ata_scsi_rbuf_put(cmd, rc == 0, &flags);
1982 
1983 	if (rc == 0)
1984 		cmd->result = SAM_STAT_GOOD;
1985 	args->done(cmd);
1986 }
1987 
1988 /**
1989  *	ata_scsiop_inq_std - Simulate INQUIRY command
1990  *	@args: device IDENTIFY data / SCSI command of interest.
1991  *	@rbuf: Response buffer, to which simulated SCSI cmd output is sent.
1992  *
1993  *	Returns standard device identification data associated
1994  *	with non-VPD INQUIRY command output.
1995  *
1996  *	LOCKING:
1997  *	spin_lock_irqsave(host lock)
1998  */
1999 static unsigned int ata_scsiop_inq_std(struct ata_scsi_args *args, u8 *rbuf)
2000 {
2001 	const u8 versions[] = {
2002 		0x00,
2003 		0x60,	/* SAM-3 (no version claimed) */
2004 
2005 		0x03,
2006 		0x20,	/* SBC-2 (no version claimed) */
2007 
2008 		0x02,
2009 		0x60	/* SPC-3 (no version claimed) */
2010 	};
2011 	const u8 versions_zbc[] = {
2012 		0x00,
2013 		0xA0,	/* SAM-5 (no version claimed) */
2014 
2015 		0x04,
2016 		0xC0,	/* SBC-3 (no version claimed) */
2017 
2018 		0x04,
2019 		0x60,	/* SPC-4 (no version claimed) */
2020 
2021 		0x60,
2022 		0x20,   /* ZBC (no version claimed) */
2023 	};
2024 
2025 	u8 hdr[] = {
2026 		TYPE_DISK,
2027 		0,
2028 		0x5,	/* claim SPC-3 version compatibility */
2029 		2,
2030 		95 - 4
2031 	};
2032 
2033 	VPRINTK("ENTER\n");
2034 
2035 	/* set scsi removable (RMB) bit per ata bit */
2036 	if (ata_id_removable(args->id))
2037 		hdr[1] |= (1 << 7);
2038 
2039 	if (args->dev->class == ATA_DEV_ZAC) {
2040 		hdr[0] = TYPE_ZBC;
2041 		hdr[2] = 0x6; /* ZBC is defined in SPC-4 */
2042 	}
2043 
2044 	memcpy(rbuf, hdr, sizeof(hdr));
2045 	memcpy(&rbuf[8], "ATA     ", 8);
2046 	ata_id_string(args->id, &rbuf[16], ATA_ID_PROD, 16);
2047 
2048 	/* From SAT, use last 2 words from fw rev unless they are spaces */
2049 	ata_id_string(args->id, &rbuf[32], ATA_ID_FW_REV + 2, 4);
2050 	if (strncmp(&rbuf[32], "    ", 4) == 0)
2051 		ata_id_string(args->id, &rbuf[32], ATA_ID_FW_REV, 4);
2052 
2053 	if (rbuf[32] == 0 || rbuf[32] == ' ')
2054 		memcpy(&rbuf[32], "n/a ", 4);
2055 
2056 	if (args->dev->class == ATA_DEV_ZAC)
2057 		memcpy(rbuf + 58, versions_zbc, sizeof(versions_zbc));
2058 	else
2059 		memcpy(rbuf + 58, versions, sizeof(versions));
2060 
2061 	return 0;
2062 }
2063 
2064 /**
2065  *	ata_scsiop_inq_00 - Simulate INQUIRY VPD page 0, list of pages
2066  *	@args: device IDENTIFY data / SCSI command of interest.
2067  *	@rbuf: Response buffer, to which simulated SCSI cmd output is sent.
2068  *
2069  *	Returns list of inquiry VPD pages available.
2070  *
2071  *	LOCKING:
2072  *	spin_lock_irqsave(host lock)
2073  */
2074 static unsigned int ata_scsiop_inq_00(struct ata_scsi_args *args, u8 *rbuf)
2075 {
2076 	const u8 pages[] = {
2077 		0x00,	/* page 0x00, this page */
2078 		0x80,	/* page 0x80, unit serial no page */
2079 		0x83,	/* page 0x83, device ident page */
2080 		0x89,	/* page 0x89, ata info page */
2081 		0xb0,	/* page 0xb0, block limits page */
2082 		0xb1,	/* page 0xb1, block device characteristics page */
2083 		0xb2,	/* page 0xb2, thin provisioning page */
2084 	};
2085 
2086 	rbuf[3] = sizeof(pages);	/* number of supported VPD pages */
2087 	memcpy(rbuf + 4, pages, sizeof(pages));
2088 	return 0;
2089 }
2090 
2091 /**
2092  *	ata_scsiop_inq_80 - Simulate INQUIRY VPD page 80, device serial number
2093  *	@args: device IDENTIFY data / SCSI command of interest.
2094  *	@rbuf: Response buffer, to which simulated SCSI cmd output is sent.
2095  *
2096  *	Returns ATA device serial number.
2097  *
2098  *	LOCKING:
2099  *	spin_lock_irqsave(host lock)
2100  */
2101 static unsigned int ata_scsiop_inq_80(struct ata_scsi_args *args, u8 *rbuf)
2102 {
2103 	const u8 hdr[] = {
2104 		0,
2105 		0x80,			/* this page code */
2106 		0,
2107 		ATA_ID_SERNO_LEN,	/* page len */
2108 	};
2109 
2110 	memcpy(rbuf, hdr, sizeof(hdr));
2111 	ata_id_string(args->id, (unsigned char *) &rbuf[4],
2112 		      ATA_ID_SERNO, ATA_ID_SERNO_LEN);
2113 	return 0;
2114 }
2115 
2116 /**
2117  *	ata_scsiop_inq_83 - Simulate INQUIRY VPD page 83, device identity
2118  *	@args: device IDENTIFY data / SCSI command of interest.
2119  *	@rbuf: Response buffer, to which simulated SCSI cmd output is sent.
2120  *
2121  *	Yields two logical unit device identification designators:
2122  *	 - vendor specific ASCII containing the ATA serial number
2123  *	 - SAT defined "t10 vendor id based" containing ASCII vendor
2124  *	   name ("ATA     "), model and serial numbers.
2125  *
2126  *	LOCKING:
2127  *	spin_lock_irqsave(host lock)
2128  */
2129 static unsigned int ata_scsiop_inq_83(struct ata_scsi_args *args, u8 *rbuf)
2130 {
2131 	const int sat_model_serial_desc_len = 68;
2132 	int num;
2133 
2134 	rbuf[1] = 0x83;			/* this page code */
2135 	num = 4;
2136 
2137 	/* piv=0, assoc=lu, code_set=ACSII, designator=vendor */
2138 	rbuf[num + 0] = 2;
2139 	rbuf[num + 3] = ATA_ID_SERNO_LEN;
2140 	num += 4;
2141 	ata_id_string(args->id, (unsigned char *) rbuf + num,
2142 		      ATA_ID_SERNO, ATA_ID_SERNO_LEN);
2143 	num += ATA_ID_SERNO_LEN;
2144 
2145 	/* SAT defined lu model and serial numbers descriptor */
2146 	/* piv=0, assoc=lu, code_set=ACSII, designator=t10 vendor id */
2147 	rbuf[num + 0] = 2;
2148 	rbuf[num + 1] = 1;
2149 	rbuf[num + 3] = sat_model_serial_desc_len;
2150 	num += 4;
2151 	memcpy(rbuf + num, "ATA     ", 8);
2152 	num += 8;
2153 	ata_id_string(args->id, (unsigned char *) rbuf + num, ATA_ID_PROD,
2154 		      ATA_ID_PROD_LEN);
2155 	num += ATA_ID_PROD_LEN;
2156 	ata_id_string(args->id, (unsigned char *) rbuf + num, ATA_ID_SERNO,
2157 		      ATA_ID_SERNO_LEN);
2158 	num += ATA_ID_SERNO_LEN;
2159 
2160 	if (ata_id_has_wwn(args->id)) {
2161 		/* SAT defined lu world wide name */
2162 		/* piv=0, assoc=lu, code_set=binary, designator=NAA */
2163 		rbuf[num + 0] = 1;
2164 		rbuf[num + 1] = 3;
2165 		rbuf[num + 3] = ATA_ID_WWN_LEN;
2166 		num += 4;
2167 		ata_id_string(args->id, (unsigned char *) rbuf + num,
2168 			      ATA_ID_WWN, ATA_ID_WWN_LEN);
2169 		num += ATA_ID_WWN_LEN;
2170 	}
2171 	rbuf[3] = num - 4;    /* page len (assume less than 256 bytes) */
2172 	return 0;
2173 }
2174 
2175 /**
2176  *	ata_scsiop_inq_89 - Simulate INQUIRY VPD page 89, ATA info
2177  *	@args: device IDENTIFY data / SCSI command of interest.
2178  *	@rbuf: Response buffer, to which simulated SCSI cmd output is sent.
2179  *
2180  *	Yields SAT-specified ATA VPD page.
2181  *
2182  *	LOCKING:
2183  *	spin_lock_irqsave(host lock)
2184  */
2185 static unsigned int ata_scsiop_inq_89(struct ata_scsi_args *args, u8 *rbuf)
2186 {
2187 	struct ata_taskfile tf;
2188 
2189 	memset(&tf, 0, sizeof(tf));
2190 
2191 	rbuf[1] = 0x89;			/* our page code */
2192 	rbuf[2] = (0x238 >> 8);		/* page size fixed at 238h */
2193 	rbuf[3] = (0x238 & 0xff);
2194 
2195 	memcpy(&rbuf[8], "linux   ", 8);
2196 	memcpy(&rbuf[16], "libata          ", 16);
2197 	memcpy(&rbuf[32], DRV_VERSION, 4);
2198 
2199 	/* we don't store the ATA device signature, so we fake it */
2200 
2201 	tf.command = ATA_DRDY;		/* really, this is Status reg */
2202 	tf.lbal = 0x1;
2203 	tf.nsect = 0x1;
2204 
2205 	ata_tf_to_fis(&tf, 0, 1, &rbuf[36]);	/* TODO: PMP? */
2206 	rbuf[36] = 0x34;		/* force D2H Reg FIS (34h) */
2207 
2208 	rbuf[56] = ATA_CMD_ID_ATA;
2209 
2210 	memcpy(&rbuf[60], &args->id[0], 512);
2211 	return 0;
2212 }
2213 
2214 static unsigned int ata_scsiop_inq_b0(struct ata_scsi_args *args, u8 *rbuf)
2215 {
2216 	u16 min_io_sectors;
2217 
2218 	rbuf[1] = 0xb0;
2219 	rbuf[3] = 0x3c;		/* required VPD size with unmap support */
2220 
2221 	/*
2222 	 * Optimal transfer length granularity.
2223 	 *
2224 	 * This is always one physical block, but for disks with a smaller
2225 	 * logical than physical sector size we need to figure out what the
2226 	 * latter is.
2227 	 */
2228 	min_io_sectors = 1 << ata_id_log2_per_physical_sector(args->id);
2229 	put_unaligned_be16(min_io_sectors, &rbuf[6]);
2230 
2231 	/*
2232 	 * Optimal unmap granularity.
2233 	 *
2234 	 * The ATA spec doesn't even know about a granularity or alignment
2235 	 * for the TRIM command.  We can leave away most of the unmap related
2236 	 * VPD page entries, but we have specifify a granularity to signal
2237 	 * that we support some form of unmap - in thise case via WRITE SAME
2238 	 * with the unmap bit set.
2239 	 */
2240 	if (ata_id_has_trim(args->id)) {
2241 		put_unaligned_be64(65535 * 512 / 8, &rbuf[36]);
2242 		put_unaligned_be32(1, &rbuf[28]);
2243 	}
2244 
2245 	return 0;
2246 }
2247 
2248 static unsigned int ata_scsiop_inq_b1(struct ata_scsi_args *args, u8 *rbuf)
2249 {
2250 	int form_factor = ata_id_form_factor(args->id);
2251 	int media_rotation_rate = ata_id_rotation_rate(args->id);
2252 
2253 	rbuf[1] = 0xb1;
2254 	rbuf[3] = 0x3c;
2255 	rbuf[4] = media_rotation_rate >> 8;
2256 	rbuf[5] = media_rotation_rate;
2257 	rbuf[7] = form_factor;
2258 
2259 	return 0;
2260 }
2261 
2262 static unsigned int ata_scsiop_inq_b2(struct ata_scsi_args *args, u8 *rbuf)
2263 {
2264 	/* SCSI Thin Provisioning VPD page: SBC-3 rev 22 or later */
2265 	rbuf[1] = 0xb2;
2266 	rbuf[3] = 0x4;
2267 	rbuf[5] = 1 << 6;	/* TPWS */
2268 
2269 	return 0;
2270 }
2271 
2272 /**
2273  *	ata_scsiop_noop - Command handler that simply returns success.
2274  *	@args: device IDENTIFY data / SCSI command of interest.
2275  *	@rbuf: Response buffer, to which simulated SCSI cmd output is sent.
2276  *
2277  *	No operation.  Simply returns success to caller, to indicate
2278  *	that the caller should successfully complete this SCSI command.
2279  *
2280  *	LOCKING:
2281  *	spin_lock_irqsave(host lock)
2282  */
2283 static unsigned int ata_scsiop_noop(struct ata_scsi_args *args, u8 *rbuf)
2284 {
2285 	VPRINTK("ENTER\n");
2286 	return 0;
2287 }
2288 
2289 /**
2290  *	modecpy - Prepare response for MODE SENSE
2291  *	@dest: output buffer
2292  *	@src: data being copied
2293  *	@n: length of mode page
2294  *	@changeable: whether changeable parameters are requested
2295  *
2296  *	Generate a generic MODE SENSE page for either current or changeable
2297  *	parameters.
2298  *
2299  *	LOCKING:
2300  *	None.
2301  */
2302 static void modecpy(u8 *dest, const u8 *src, int n, bool changeable)
2303 {
2304 	if (changeable) {
2305 		memcpy(dest, src, 2);
2306 		memset(dest + 2, 0, n - 2);
2307 	} else {
2308 		memcpy(dest, src, n);
2309 	}
2310 }
2311 
2312 /**
2313  *	ata_msense_caching - Simulate MODE SENSE caching info page
2314  *	@id: device IDENTIFY data
2315  *	@buf: output buffer
2316  *	@changeable: whether changeable parameters are requested
2317  *
2318  *	Generate a caching info page, which conditionally indicates
2319  *	write caching to the SCSI layer, depending on device
2320  *	capabilities.
2321  *
2322  *	LOCKING:
2323  *	None.
2324  */
2325 static unsigned int ata_msense_caching(u16 *id, u8 *buf, bool changeable)
2326 {
2327 	modecpy(buf, def_cache_mpage, sizeof(def_cache_mpage), changeable);
2328 	if (changeable || ata_id_wcache_enabled(id))
2329 		buf[2] |= (1 << 2);	/* write cache enable */
2330 	if (!changeable && !ata_id_rahead_enabled(id))
2331 		buf[12] |= (1 << 5);	/* disable read ahead */
2332 	return sizeof(def_cache_mpage);
2333 }
2334 
2335 /**
2336  *	ata_msense_ctl_mode - Simulate MODE SENSE control mode page
2337  *	@buf: output buffer
2338  *	@changeable: whether changeable parameters are requested
2339  *
2340  *	Generate a generic MODE SENSE control mode page.
2341  *
2342  *	LOCKING:
2343  *	None.
2344  */
2345 static unsigned int ata_msense_ctl_mode(u8 *buf, bool changeable)
2346 {
2347 	modecpy(buf, def_control_mpage, sizeof(def_control_mpage), changeable);
2348 	return sizeof(def_control_mpage);
2349 }
2350 
2351 /**
2352  *	ata_msense_rw_recovery - Simulate MODE SENSE r/w error recovery page
2353  *	@buf: output buffer
2354  *	@changeable: whether changeable parameters are requested
2355  *
2356  *	Generate a generic MODE SENSE r/w error recovery page.
2357  *
2358  *	LOCKING:
2359  *	None.
2360  */
2361 static unsigned int ata_msense_rw_recovery(u8 *buf, bool changeable)
2362 {
2363 	modecpy(buf, def_rw_recovery_mpage, sizeof(def_rw_recovery_mpage),
2364 		changeable);
2365 	return sizeof(def_rw_recovery_mpage);
2366 }
2367 
2368 /*
2369  * We can turn this into a real blacklist if it's needed, for now just
2370  * blacklist any Maxtor BANC1G10 revision firmware
2371  */
2372 static int ata_dev_supports_fua(u16 *id)
2373 {
2374 	unsigned char model[ATA_ID_PROD_LEN + 1], fw[ATA_ID_FW_REV_LEN + 1];
2375 
2376 	if (!libata_fua)
2377 		return 0;
2378 	if (!ata_id_has_fua(id))
2379 		return 0;
2380 
2381 	ata_id_c_string(id, model, ATA_ID_PROD, sizeof(model));
2382 	ata_id_c_string(id, fw, ATA_ID_FW_REV, sizeof(fw));
2383 
2384 	if (strcmp(model, "Maxtor"))
2385 		return 1;
2386 	if (strcmp(fw, "BANC1G10"))
2387 		return 1;
2388 
2389 	return 0; /* blacklisted */
2390 }
2391 
2392 /**
2393  *	ata_scsiop_mode_sense - Simulate MODE SENSE 6, 10 commands
2394  *	@args: device IDENTIFY data / SCSI command of interest.
2395  *	@rbuf: Response buffer, to which simulated SCSI cmd output is sent.
2396  *
2397  *	Simulate MODE SENSE commands. Assume this is invoked for direct
2398  *	access devices (e.g. disks) only. There should be no block
2399  *	descriptor for other device types.
2400  *
2401  *	LOCKING:
2402  *	spin_lock_irqsave(host lock)
2403  */
2404 static unsigned int ata_scsiop_mode_sense(struct ata_scsi_args *args, u8 *rbuf)
2405 {
2406 	struct ata_device *dev = args->dev;
2407 	u8 *scsicmd = args->cmd->cmnd, *p = rbuf;
2408 	const u8 sat_blk_desc[] = {
2409 		0, 0, 0, 0,	/* number of blocks: sat unspecified */
2410 		0,
2411 		0, 0x2, 0x0	/* block length: 512 bytes */
2412 	};
2413 	u8 pg, spg;
2414 	unsigned int ebd, page_control, six_byte;
2415 	u8 dpofua;
2416 
2417 	VPRINTK("ENTER\n");
2418 
2419 	six_byte = (scsicmd[0] == MODE_SENSE);
2420 	ebd = !(scsicmd[1] & 0x8);      /* dbd bit inverted == edb */
2421 	/*
2422 	 * LLBA bit in msense(10) ignored (compliant)
2423 	 */
2424 
2425 	page_control = scsicmd[2] >> 6;
2426 	switch (page_control) {
2427 	case 0: /* current */
2428 	case 1: /* changeable */
2429 	case 2: /* defaults */
2430 		break;  /* supported */
2431 	case 3: /* saved */
2432 		goto saving_not_supp;
2433 	default:
2434 		goto invalid_fld;
2435 	}
2436 
2437 	if (six_byte)
2438 		p += 4 + (ebd ? 8 : 0);
2439 	else
2440 		p += 8 + (ebd ? 8 : 0);
2441 
2442 	pg = scsicmd[2] & 0x3f;
2443 	spg = scsicmd[3];
2444 	/*
2445 	 * No mode subpages supported (yet) but asking for _all_
2446 	 * subpages may be valid
2447 	 */
2448 	if (spg && (spg != ALL_SUB_MPAGES))
2449 		goto invalid_fld;
2450 
2451 	switch(pg) {
2452 	case RW_RECOVERY_MPAGE:
2453 		p += ata_msense_rw_recovery(p, page_control == 1);
2454 		break;
2455 
2456 	case CACHE_MPAGE:
2457 		p += ata_msense_caching(args->id, p, page_control == 1);
2458 		break;
2459 
2460 	case CONTROL_MPAGE:
2461 		p += ata_msense_ctl_mode(p, page_control == 1);
2462 		break;
2463 
2464 	case ALL_MPAGES:
2465 		p += ata_msense_rw_recovery(p, page_control == 1);
2466 		p += ata_msense_caching(args->id, p, page_control == 1);
2467 		p += ata_msense_ctl_mode(p, page_control == 1);
2468 		break;
2469 
2470 	default:		/* invalid page code */
2471 		goto invalid_fld;
2472 	}
2473 
2474 	dpofua = 0;
2475 	if (ata_dev_supports_fua(args->id) && (dev->flags & ATA_DFLAG_LBA48) &&
2476 	    (!(dev->flags & ATA_DFLAG_PIO) || dev->multi_count))
2477 		dpofua = 1 << 4;
2478 
2479 	if (six_byte) {
2480 		rbuf[0] = p - rbuf - 1;
2481 		rbuf[2] |= dpofua;
2482 		if (ebd) {
2483 			rbuf[3] = sizeof(sat_blk_desc);
2484 			memcpy(rbuf + 4, sat_blk_desc, sizeof(sat_blk_desc));
2485 		}
2486 	} else {
2487 		unsigned int output_len = p - rbuf - 2;
2488 
2489 		rbuf[0] = output_len >> 8;
2490 		rbuf[1] = output_len;
2491 		rbuf[3] |= dpofua;
2492 		if (ebd) {
2493 			rbuf[7] = sizeof(sat_blk_desc);
2494 			memcpy(rbuf + 8, sat_blk_desc, sizeof(sat_blk_desc));
2495 		}
2496 	}
2497 	return 0;
2498 
2499 invalid_fld:
2500 	ata_scsi_set_sense(args->cmd, ILLEGAL_REQUEST, 0x24, 0x0);
2501 	/* "Invalid field in cbd" */
2502 	return 1;
2503 
2504 saving_not_supp:
2505 	ata_scsi_set_sense(args->cmd, ILLEGAL_REQUEST, 0x39, 0x0);
2506 	 /* "Saving parameters not supported" */
2507 	return 1;
2508 }
2509 
2510 /**
2511  *	ata_scsiop_read_cap - Simulate READ CAPACITY[ 16] commands
2512  *	@args: device IDENTIFY data / SCSI command of interest.
2513  *	@rbuf: Response buffer, to which simulated SCSI cmd output is sent.
2514  *
2515  *	Simulate READ CAPACITY commands.
2516  *
2517  *	LOCKING:
2518  *	None.
2519  */
2520 static unsigned int ata_scsiop_read_cap(struct ata_scsi_args *args, u8 *rbuf)
2521 {
2522 	struct ata_device *dev = args->dev;
2523 	u64 last_lba = dev->n_sectors - 1; /* LBA of the last block */
2524 	u32 sector_size; /* physical sector size in bytes */
2525 	u8 log2_per_phys;
2526 	u16 lowest_aligned;
2527 
2528 	sector_size = ata_id_logical_sector_size(dev->id);
2529 	log2_per_phys = ata_id_log2_per_physical_sector(dev->id);
2530 	lowest_aligned = ata_id_logical_sector_offset(dev->id, log2_per_phys);
2531 
2532 	VPRINTK("ENTER\n");
2533 
2534 	if (args->cmd->cmnd[0] == READ_CAPACITY) {
2535 		if (last_lba >= 0xffffffffULL)
2536 			last_lba = 0xffffffff;
2537 
2538 		/* sector count, 32-bit */
2539 		rbuf[0] = last_lba >> (8 * 3);
2540 		rbuf[1] = last_lba >> (8 * 2);
2541 		rbuf[2] = last_lba >> (8 * 1);
2542 		rbuf[3] = last_lba;
2543 
2544 		/* sector size */
2545 		rbuf[4] = sector_size >> (8 * 3);
2546 		rbuf[5] = sector_size >> (8 * 2);
2547 		rbuf[6] = sector_size >> (8 * 1);
2548 		rbuf[7] = sector_size;
2549 	} else {
2550 		/* sector count, 64-bit */
2551 		rbuf[0] = last_lba >> (8 * 7);
2552 		rbuf[1] = last_lba >> (8 * 6);
2553 		rbuf[2] = last_lba >> (8 * 5);
2554 		rbuf[3] = last_lba >> (8 * 4);
2555 		rbuf[4] = last_lba >> (8 * 3);
2556 		rbuf[5] = last_lba >> (8 * 2);
2557 		rbuf[6] = last_lba >> (8 * 1);
2558 		rbuf[7] = last_lba;
2559 
2560 		/* sector size */
2561 		rbuf[ 8] = sector_size >> (8 * 3);
2562 		rbuf[ 9] = sector_size >> (8 * 2);
2563 		rbuf[10] = sector_size >> (8 * 1);
2564 		rbuf[11] = sector_size;
2565 
2566 		rbuf[12] = 0;
2567 		rbuf[13] = log2_per_phys;
2568 		rbuf[14] = (lowest_aligned >> 8) & 0x3f;
2569 		rbuf[15] = lowest_aligned;
2570 
2571 		if (ata_id_has_trim(args->id)) {
2572 			rbuf[14] |= 0x80; /* LBPME */
2573 
2574 			if (ata_id_has_zero_after_trim(args->id) &&
2575 			    dev->horkage & ATA_HORKAGE_ZERO_AFTER_TRIM) {
2576 				ata_dev_info(dev, "Enabling discard_zeroes_data\n");
2577 				rbuf[14] |= 0x40; /* LBPRZ */
2578 			}
2579 		}
2580 	}
2581 	return 0;
2582 }
2583 
2584 /**
2585  *	ata_scsiop_report_luns - Simulate REPORT LUNS command
2586  *	@args: device IDENTIFY data / SCSI command of interest.
2587  *	@rbuf: Response buffer, to which simulated SCSI cmd output is sent.
2588  *
2589  *	Simulate REPORT LUNS command.
2590  *
2591  *	LOCKING:
2592  *	spin_lock_irqsave(host lock)
2593  */
2594 static unsigned int ata_scsiop_report_luns(struct ata_scsi_args *args, u8 *rbuf)
2595 {
2596 	VPRINTK("ENTER\n");
2597 	rbuf[3] = 8;	/* just one lun, LUN 0, size 8 bytes */
2598 
2599 	return 0;
2600 }
2601 
2602 static void atapi_sense_complete(struct ata_queued_cmd *qc)
2603 {
2604 	if (qc->err_mask && ((qc->err_mask & AC_ERR_DEV) == 0)) {
2605 		/* FIXME: not quite right; we don't want the
2606 		 * translation of taskfile registers into
2607 		 * a sense descriptors, since that's only
2608 		 * correct for ATA, not ATAPI
2609 		 */
2610 		ata_gen_passthru_sense(qc);
2611 	}
2612 
2613 	qc->scsidone(qc->scsicmd);
2614 	ata_qc_free(qc);
2615 }
2616 
2617 /* is it pointless to prefer PIO for "safety reasons"? */
2618 static inline int ata_pio_use_silly(struct ata_port *ap)
2619 {
2620 	return (ap->flags & ATA_FLAG_PIO_DMA);
2621 }
2622 
2623 static void atapi_request_sense(struct ata_queued_cmd *qc)
2624 {
2625 	struct ata_port *ap = qc->ap;
2626 	struct scsi_cmnd *cmd = qc->scsicmd;
2627 
2628 	DPRINTK("ATAPI request sense\n");
2629 
2630 	memset(cmd->sense_buffer, 0, SCSI_SENSE_BUFFERSIZE);
2631 
2632 #ifdef CONFIG_ATA_SFF
2633 	if (ap->ops->sff_tf_read)
2634 		ap->ops->sff_tf_read(ap, &qc->tf);
2635 #endif
2636 
2637 	/* fill these in, for the case where they are -not- overwritten */
2638 	cmd->sense_buffer[0] = 0x70;
2639 	cmd->sense_buffer[2] = qc->tf.feature >> 4;
2640 
2641 	ata_qc_reinit(qc);
2642 
2643 	/* setup sg table and init transfer direction */
2644 	sg_init_one(&qc->sgent, cmd->sense_buffer, SCSI_SENSE_BUFFERSIZE);
2645 	ata_sg_init(qc, &qc->sgent, 1);
2646 	qc->dma_dir = DMA_FROM_DEVICE;
2647 
2648 	memset(&qc->cdb, 0, qc->dev->cdb_len);
2649 	qc->cdb[0] = REQUEST_SENSE;
2650 	qc->cdb[4] = SCSI_SENSE_BUFFERSIZE;
2651 
2652 	qc->tf.flags |= ATA_TFLAG_ISADDR | ATA_TFLAG_DEVICE;
2653 	qc->tf.command = ATA_CMD_PACKET;
2654 
2655 	if (ata_pio_use_silly(ap)) {
2656 		qc->tf.protocol = ATAPI_PROT_DMA;
2657 		qc->tf.feature |= ATAPI_PKT_DMA;
2658 	} else {
2659 		qc->tf.protocol = ATAPI_PROT_PIO;
2660 		qc->tf.lbam = SCSI_SENSE_BUFFERSIZE;
2661 		qc->tf.lbah = 0;
2662 	}
2663 	qc->nbytes = SCSI_SENSE_BUFFERSIZE;
2664 
2665 	qc->complete_fn = atapi_sense_complete;
2666 
2667 	ata_qc_issue(qc);
2668 
2669 	DPRINTK("EXIT\n");
2670 }
2671 
2672 static void atapi_qc_complete(struct ata_queued_cmd *qc)
2673 {
2674 	struct scsi_cmnd *cmd = qc->scsicmd;
2675 	unsigned int err_mask = qc->err_mask;
2676 
2677 	VPRINTK("ENTER, err_mask 0x%X\n", err_mask);
2678 
2679 	/* handle completion from new EH */
2680 	if (unlikely(qc->ap->ops->error_handler &&
2681 		     (err_mask || qc->flags & ATA_QCFLAG_SENSE_VALID))) {
2682 
2683 		if (!(qc->flags & ATA_QCFLAG_SENSE_VALID)) {
2684 			/* FIXME: not quite right; we don't want the
2685 			 * translation of taskfile registers into a
2686 			 * sense descriptors, since that's only
2687 			 * correct for ATA, not ATAPI
2688 			 */
2689 			ata_gen_passthru_sense(qc);
2690 		}
2691 
2692 		/* SCSI EH automatically locks door if sdev->locked is
2693 		 * set.  Sometimes door lock request continues to
2694 		 * fail, for example, when no media is present.  This
2695 		 * creates a loop - SCSI EH issues door lock which
2696 		 * fails and gets invoked again to acquire sense data
2697 		 * for the failed command.
2698 		 *
2699 		 * If door lock fails, always clear sdev->locked to
2700 		 * avoid this infinite loop.
2701 		 *
2702 		 * This may happen before SCSI scan is complete.  Make
2703 		 * sure qc->dev->sdev isn't NULL before dereferencing.
2704 		 */
2705 		if (qc->cdb[0] == ALLOW_MEDIUM_REMOVAL && qc->dev->sdev)
2706 			qc->dev->sdev->locked = 0;
2707 
2708 		qc->scsicmd->result = SAM_STAT_CHECK_CONDITION;
2709 		qc->scsidone(cmd);
2710 		ata_qc_free(qc);
2711 		return;
2712 	}
2713 
2714 	/* successful completion or old EH failure path */
2715 	if (unlikely(err_mask & AC_ERR_DEV)) {
2716 		cmd->result = SAM_STAT_CHECK_CONDITION;
2717 		atapi_request_sense(qc);
2718 		return;
2719 	} else if (unlikely(err_mask)) {
2720 		/* FIXME: not quite right; we don't want the
2721 		 * translation of taskfile registers into
2722 		 * a sense descriptors, since that's only
2723 		 * correct for ATA, not ATAPI
2724 		 */
2725 		ata_gen_passthru_sense(qc);
2726 	} else {
2727 		u8 *scsicmd = cmd->cmnd;
2728 
2729 		if ((scsicmd[0] == INQUIRY) && ((scsicmd[1] & 0x03) == 0)) {
2730 			unsigned long flags;
2731 			u8 *buf;
2732 
2733 			buf = ata_scsi_rbuf_get(cmd, true, &flags);
2734 
2735 	/* ATAPI devices typically report zero for their SCSI version,
2736 	 * and sometimes deviate from the spec WRT response data
2737 	 * format.  If SCSI version is reported as zero like normal,
2738 	 * then we make the following fixups:  1) Fake MMC-5 version,
2739 	 * to indicate to the Linux scsi midlayer this is a modern
2740 	 * device.  2) Ensure response data format / ATAPI information
2741 	 * are always correct.
2742 	 */
2743 			if (buf[2] == 0) {
2744 				buf[2] = 0x5;
2745 				buf[3] = 0x32;
2746 			}
2747 
2748 			ata_scsi_rbuf_put(cmd, true, &flags);
2749 		}
2750 
2751 		cmd->result = SAM_STAT_GOOD;
2752 	}
2753 
2754 	qc->scsidone(cmd);
2755 	ata_qc_free(qc);
2756 }
2757 /**
2758  *	atapi_xlat - Initialize PACKET taskfile
2759  *	@qc: command structure to be initialized
2760  *
2761  *	LOCKING:
2762  *	spin_lock_irqsave(host lock)
2763  *
2764  *	RETURNS:
2765  *	Zero on success, non-zero on failure.
2766  */
2767 static unsigned int atapi_xlat(struct ata_queued_cmd *qc)
2768 {
2769 	struct scsi_cmnd *scmd = qc->scsicmd;
2770 	struct ata_device *dev = qc->dev;
2771 	int nodata = (scmd->sc_data_direction == DMA_NONE);
2772 	int using_pio = !nodata && (dev->flags & ATA_DFLAG_PIO);
2773 	unsigned int nbytes;
2774 
2775 	memset(qc->cdb, 0, dev->cdb_len);
2776 	memcpy(qc->cdb, scmd->cmnd, scmd->cmd_len);
2777 
2778 	qc->complete_fn = atapi_qc_complete;
2779 
2780 	qc->tf.flags |= ATA_TFLAG_ISADDR | ATA_TFLAG_DEVICE;
2781 	if (scmd->sc_data_direction == DMA_TO_DEVICE) {
2782 		qc->tf.flags |= ATA_TFLAG_WRITE;
2783 		DPRINTK("direction: write\n");
2784 	}
2785 
2786 	qc->tf.command = ATA_CMD_PACKET;
2787 	ata_qc_set_pc_nbytes(qc);
2788 
2789 	/* check whether ATAPI DMA is safe */
2790 	if (!nodata && !using_pio && atapi_check_dma(qc))
2791 		using_pio = 1;
2792 
2793 	/* Some controller variants snoop this value for Packet
2794 	 * transfers to do state machine and FIFO management.  Thus we
2795 	 * want to set it properly, and for DMA where it is
2796 	 * effectively meaningless.
2797 	 */
2798 	nbytes = min(ata_qc_raw_nbytes(qc), (unsigned int)63 * 1024);
2799 
2800 	/* Most ATAPI devices which honor transfer chunk size don't
2801 	 * behave according to the spec when odd chunk size which
2802 	 * matches the transfer length is specified.  If the number of
2803 	 * bytes to transfer is 2n+1.  According to the spec, what
2804 	 * should happen is to indicate that 2n+1 is going to be
2805 	 * transferred and transfer 2n+2 bytes where the last byte is
2806 	 * padding.
2807 	 *
2808 	 * In practice, this doesn't happen.  ATAPI devices first
2809 	 * indicate and transfer 2n bytes and then indicate and
2810 	 * transfer 2 bytes where the last byte is padding.
2811 	 *
2812 	 * This inconsistency confuses several controllers which
2813 	 * perform PIO using DMA such as Intel AHCIs and sil3124/32.
2814 	 * These controllers use actual number of transferred bytes to
2815 	 * update DMA poitner and transfer of 4n+2 bytes make those
2816 	 * controller push DMA pointer by 4n+4 bytes because SATA data
2817 	 * FISes are aligned to 4 bytes.  This causes data corruption
2818 	 * and buffer overrun.
2819 	 *
2820 	 * Always setting nbytes to even number solves this problem
2821 	 * because then ATAPI devices don't have to split data at 2n
2822 	 * boundaries.
2823 	 */
2824 	if (nbytes & 0x1)
2825 		nbytes++;
2826 
2827 	qc->tf.lbam = (nbytes & 0xFF);
2828 	qc->tf.lbah = (nbytes >> 8);
2829 
2830 	if (nodata)
2831 		qc->tf.protocol = ATAPI_PROT_NODATA;
2832 	else if (using_pio)
2833 		qc->tf.protocol = ATAPI_PROT_PIO;
2834 	else {
2835 		/* DMA data xfer */
2836 		qc->tf.protocol = ATAPI_PROT_DMA;
2837 		qc->tf.feature |= ATAPI_PKT_DMA;
2838 
2839 		if ((dev->flags & ATA_DFLAG_DMADIR) &&
2840 		    (scmd->sc_data_direction != DMA_TO_DEVICE))
2841 			/* some SATA bridges need us to indicate data xfer direction */
2842 			qc->tf.feature |= ATAPI_DMADIR;
2843 	}
2844 
2845 
2846 	/* FIXME: We need to translate 0x05 READ_BLOCK_LIMITS to a MODE_SENSE
2847 	   as ATAPI tape drives don't get this right otherwise */
2848 	return 0;
2849 }
2850 
2851 static struct ata_device *ata_find_dev(struct ata_port *ap, int devno)
2852 {
2853 	if (!sata_pmp_attached(ap)) {
2854 		if (likely(devno < ata_link_max_devices(&ap->link)))
2855 			return &ap->link.device[devno];
2856 	} else {
2857 		if (likely(devno < ap->nr_pmp_links))
2858 			return &ap->pmp_link[devno].device[0];
2859 	}
2860 
2861 	return NULL;
2862 }
2863 
2864 static struct ata_device *__ata_scsi_find_dev(struct ata_port *ap,
2865 					      const struct scsi_device *scsidev)
2866 {
2867 	int devno;
2868 
2869 	/* skip commands not addressed to targets we simulate */
2870 	if (!sata_pmp_attached(ap)) {
2871 		if (unlikely(scsidev->channel || scsidev->lun))
2872 			return NULL;
2873 		devno = scsidev->id;
2874 	} else {
2875 		if (unlikely(scsidev->id || scsidev->lun))
2876 			return NULL;
2877 		devno = scsidev->channel;
2878 	}
2879 
2880 	return ata_find_dev(ap, devno);
2881 }
2882 
2883 /**
2884  *	ata_scsi_find_dev - lookup ata_device from scsi_cmnd
2885  *	@ap: ATA port to which the device is attached
2886  *	@scsidev: SCSI device from which we derive the ATA device
2887  *
2888  *	Given various information provided in struct scsi_cmnd,
2889  *	map that onto an ATA bus, and using that mapping
2890  *	determine which ata_device is associated with the
2891  *	SCSI command to be sent.
2892  *
2893  *	LOCKING:
2894  *	spin_lock_irqsave(host lock)
2895  *
2896  *	RETURNS:
2897  *	Associated ATA device, or %NULL if not found.
2898  */
2899 static struct ata_device *
2900 ata_scsi_find_dev(struct ata_port *ap, const struct scsi_device *scsidev)
2901 {
2902 	struct ata_device *dev = __ata_scsi_find_dev(ap, scsidev);
2903 
2904 	if (unlikely(!dev || !ata_dev_enabled(dev)))
2905 		return NULL;
2906 
2907 	return dev;
2908 }
2909 
2910 /*
2911  *	ata_scsi_map_proto - Map pass-thru protocol value to taskfile value.
2912  *	@byte1: Byte 1 from pass-thru CDB.
2913  *
2914  *	RETURNS:
2915  *	ATA_PROT_UNKNOWN if mapping failed/unimplemented, protocol otherwise.
2916  */
2917 static u8
2918 ata_scsi_map_proto(u8 byte1)
2919 {
2920 	switch((byte1 & 0x1e) >> 1) {
2921 	case 3:		/* Non-data */
2922 		return ATA_PROT_NODATA;
2923 
2924 	case 6:		/* DMA */
2925 	case 10:	/* UDMA Data-in */
2926 	case 11:	/* UDMA Data-Out */
2927 		return ATA_PROT_DMA;
2928 
2929 	case 4:		/* PIO Data-in */
2930 	case 5:		/* PIO Data-out */
2931 		return ATA_PROT_PIO;
2932 
2933 	case 0:		/* Hard Reset */
2934 	case 1:		/* SRST */
2935 	case 8:		/* Device Diagnostic */
2936 	case 9:		/* Device Reset */
2937 	case 7:		/* DMA Queued */
2938 	case 12:	/* FPDMA */
2939 	case 15:	/* Return Response Info */
2940 	default:	/* Reserved */
2941 		break;
2942 	}
2943 
2944 	return ATA_PROT_UNKNOWN;
2945 }
2946 
2947 /**
2948  *	ata_scsi_pass_thru - convert ATA pass-thru CDB to taskfile
2949  *	@qc: command structure to be initialized
2950  *
2951  *	Handles either 12 or 16-byte versions of the CDB.
2952  *
2953  *	RETURNS:
2954  *	Zero on success, non-zero on failure.
2955  */
2956 static unsigned int ata_scsi_pass_thru(struct ata_queued_cmd *qc)
2957 {
2958 	struct ata_taskfile *tf = &(qc->tf);
2959 	struct scsi_cmnd *scmd = qc->scsicmd;
2960 	struct ata_device *dev = qc->dev;
2961 	const u8 *cdb = scmd->cmnd;
2962 
2963 	if ((tf->protocol = ata_scsi_map_proto(cdb[1])) == ATA_PROT_UNKNOWN)
2964 		goto invalid_fld;
2965 
2966 	/*
2967 	 * 12 and 16 byte CDBs use different offsets to
2968 	 * provide the various register values.
2969 	 */
2970 	if (cdb[0] == ATA_16) {
2971 		/*
2972 		 * 16-byte CDB - may contain extended commands.
2973 		 *
2974 		 * If that is the case, copy the upper byte register values.
2975 		 */
2976 		if (cdb[1] & 0x01) {
2977 			tf->hob_feature = cdb[3];
2978 			tf->hob_nsect = cdb[5];
2979 			tf->hob_lbal = cdb[7];
2980 			tf->hob_lbam = cdb[9];
2981 			tf->hob_lbah = cdb[11];
2982 			tf->flags |= ATA_TFLAG_LBA48;
2983 		} else
2984 			tf->flags &= ~ATA_TFLAG_LBA48;
2985 
2986 		/*
2987 		 * Always copy low byte, device and command registers.
2988 		 */
2989 		tf->feature = cdb[4];
2990 		tf->nsect = cdb[6];
2991 		tf->lbal = cdb[8];
2992 		tf->lbam = cdb[10];
2993 		tf->lbah = cdb[12];
2994 		tf->device = cdb[13];
2995 		tf->command = cdb[14];
2996 	} else {
2997 		/*
2998 		 * 12-byte CDB - incapable of extended commands.
2999 		 */
3000 		tf->flags &= ~ATA_TFLAG_LBA48;
3001 
3002 		tf->feature = cdb[3];
3003 		tf->nsect = cdb[4];
3004 		tf->lbal = cdb[5];
3005 		tf->lbam = cdb[6];
3006 		tf->lbah = cdb[7];
3007 		tf->device = cdb[8];
3008 		tf->command = cdb[9];
3009 	}
3010 
3011 	/* enforce correct master/slave bit */
3012 	tf->device = dev->devno ?
3013 		tf->device | ATA_DEV1 : tf->device & ~ATA_DEV1;
3014 
3015 	switch (tf->command) {
3016 	/* READ/WRITE LONG use a non-standard sect_size */
3017 	case ATA_CMD_READ_LONG:
3018 	case ATA_CMD_READ_LONG_ONCE:
3019 	case ATA_CMD_WRITE_LONG:
3020 	case ATA_CMD_WRITE_LONG_ONCE:
3021 		if (tf->protocol != ATA_PROT_PIO || tf->nsect != 1)
3022 			goto invalid_fld;
3023 		qc->sect_size = scsi_bufflen(scmd);
3024 		break;
3025 
3026 	/* commands using reported Logical Block size (e.g. 512 or 4K) */
3027 	case ATA_CMD_CFA_WRITE_NE:
3028 	case ATA_CMD_CFA_TRANS_SECT:
3029 	case ATA_CMD_CFA_WRITE_MULT_NE:
3030 	/* XXX: case ATA_CMD_CFA_WRITE_SECTORS_WITHOUT_ERASE: */
3031 	case ATA_CMD_READ:
3032 	case ATA_CMD_READ_EXT:
3033 	case ATA_CMD_READ_QUEUED:
3034 	/* XXX: case ATA_CMD_READ_QUEUED_EXT: */
3035 	case ATA_CMD_FPDMA_READ:
3036 	case ATA_CMD_READ_MULTI:
3037 	case ATA_CMD_READ_MULTI_EXT:
3038 	case ATA_CMD_PIO_READ:
3039 	case ATA_CMD_PIO_READ_EXT:
3040 	case ATA_CMD_READ_STREAM_DMA_EXT:
3041 	case ATA_CMD_READ_STREAM_EXT:
3042 	case ATA_CMD_VERIFY:
3043 	case ATA_CMD_VERIFY_EXT:
3044 	case ATA_CMD_WRITE:
3045 	case ATA_CMD_WRITE_EXT:
3046 	case ATA_CMD_WRITE_FUA_EXT:
3047 	case ATA_CMD_WRITE_QUEUED:
3048 	case ATA_CMD_WRITE_QUEUED_FUA_EXT:
3049 	case ATA_CMD_FPDMA_WRITE:
3050 	case ATA_CMD_WRITE_MULTI:
3051 	case ATA_CMD_WRITE_MULTI_EXT:
3052 	case ATA_CMD_WRITE_MULTI_FUA_EXT:
3053 	case ATA_CMD_PIO_WRITE:
3054 	case ATA_CMD_PIO_WRITE_EXT:
3055 	case ATA_CMD_WRITE_STREAM_DMA_EXT:
3056 	case ATA_CMD_WRITE_STREAM_EXT:
3057 		qc->sect_size = scmd->device->sector_size;
3058 		break;
3059 
3060 	/* Everything else uses 512 byte "sectors" */
3061 	default:
3062 		qc->sect_size = ATA_SECT_SIZE;
3063 	}
3064 
3065 	/*
3066 	 * Set flags so that all registers will be written, pass on
3067 	 * write indication (used for PIO/DMA setup), result TF is
3068 	 * copied back and we don't whine too much about its failure.
3069 	 */
3070 	tf->flags |= ATA_TFLAG_ISADDR | ATA_TFLAG_DEVICE;
3071 	if (scmd->sc_data_direction == DMA_TO_DEVICE)
3072 		tf->flags |= ATA_TFLAG_WRITE;
3073 
3074 	qc->flags |= ATA_QCFLAG_RESULT_TF | ATA_QCFLAG_QUIET;
3075 
3076 	/*
3077 	 * Set transfer length.
3078 	 *
3079 	 * TODO: find out if we need to do more here to
3080 	 *       cover scatter/gather case.
3081 	 */
3082 	ata_qc_set_pc_nbytes(qc);
3083 
3084 	/* We may not issue DMA commands if no DMA mode is set */
3085 	if (tf->protocol == ATA_PROT_DMA && dev->dma_mode == 0)
3086 		goto invalid_fld;
3087 
3088 	/* sanity check for pio multi commands */
3089 	if ((cdb[1] & 0xe0) && !is_multi_taskfile(tf))
3090 		goto invalid_fld;
3091 
3092 	if (is_multi_taskfile(tf)) {
3093 		unsigned int multi_count = 1 << (cdb[1] >> 5);
3094 
3095 		/* compare the passed through multi_count
3096 		 * with the cached multi_count of libata
3097 		 */
3098 		if (multi_count != dev->multi_count)
3099 			ata_dev_warn(dev, "invalid multi_count %u ignored\n",
3100 				     multi_count);
3101 	}
3102 
3103 	/*
3104 	 * Filter SET_FEATURES - XFER MODE command -- otherwise,
3105 	 * SET_FEATURES - XFER MODE must be preceded/succeeded
3106 	 * by an update to hardware-specific registers for each
3107 	 * controller (i.e. the reason for ->set_piomode(),
3108 	 * ->set_dmamode(), and ->post_set_mode() hooks).
3109 	 */
3110 	if (tf->command == ATA_CMD_SET_FEATURES &&
3111 	    tf->feature == SETFEATURES_XFER)
3112 		goto invalid_fld;
3113 
3114 	/*
3115 	 * Filter TPM commands by default. These provide an
3116 	 * essentially uncontrolled encrypted "back door" between
3117 	 * applications and the disk. Set libata.allow_tpm=1 if you
3118 	 * have a real reason for wanting to use them. This ensures
3119 	 * that installed software cannot easily mess stuff up without
3120 	 * user intent. DVR type users will probably ship with this enabled
3121 	 * for movie content management.
3122 	 *
3123 	 * Note that for ATA8 we can issue a DCS change and DCS freeze lock
3124 	 * for this and should do in future but that it is not sufficient as
3125 	 * DCS is an optional feature set. Thus we also do the software filter
3126 	 * so that we comply with the TC consortium stated goal that the user
3127 	 * can turn off TC features of their system.
3128 	 */
3129 	if (tf->command >= 0x5C && tf->command <= 0x5F && !libata_allow_tpm)
3130 		goto invalid_fld;
3131 
3132 	return 0;
3133 
3134  invalid_fld:
3135 	ata_scsi_set_sense(scmd, ILLEGAL_REQUEST, 0x24, 0x00);
3136 	/* "Invalid field in cdb" */
3137 	return 1;
3138 }
3139 
3140 static unsigned int ata_scsi_write_same_xlat(struct ata_queued_cmd *qc)
3141 {
3142 	struct ata_taskfile *tf = &qc->tf;
3143 	struct scsi_cmnd *scmd = qc->scsicmd;
3144 	struct ata_device *dev = qc->dev;
3145 	const u8 *cdb = scmd->cmnd;
3146 	u64 block;
3147 	u32 n_block;
3148 	u32 size;
3149 	void *buf;
3150 
3151 	/* we may not issue DMA commands if no DMA mode is set */
3152 	if (unlikely(!dev->dma_mode))
3153 		goto invalid_fld;
3154 
3155 	if (unlikely(scmd->cmd_len < 16))
3156 		goto invalid_fld;
3157 	scsi_16_lba_len(cdb, &block, &n_block);
3158 
3159 	/* for now we only support WRITE SAME with the unmap bit set */
3160 	if (unlikely(!(cdb[1] & 0x8)))
3161 		goto invalid_fld;
3162 
3163 	/*
3164 	 * WRITE SAME always has a sector sized buffer as payload, this
3165 	 * should never be a multiple entry S/G list.
3166 	 */
3167 	if (!scsi_sg_count(scmd))
3168 		goto invalid_fld;
3169 
3170 	buf = page_address(sg_page(scsi_sglist(scmd)));
3171 	size = ata_set_lba_range_entries(buf, 512, block, n_block);
3172 
3173 	if (ata_ncq_enabled(dev) && ata_fpdma_dsm_supported(dev)) {
3174 		/* Newer devices support queued TRIM commands */
3175 		tf->protocol = ATA_PROT_NCQ;
3176 		tf->command = ATA_CMD_FPDMA_SEND;
3177 		tf->hob_nsect = ATA_SUBCMD_FPDMA_SEND_DSM & 0x1f;
3178 		tf->nsect = qc->tag << 3;
3179 		tf->hob_feature = (size / 512) >> 8;
3180 		tf->feature = size / 512;
3181 
3182 		tf->auxiliary = 1;
3183 	} else {
3184 		tf->protocol = ATA_PROT_DMA;
3185 		tf->hob_feature = 0;
3186 		tf->feature = ATA_DSM_TRIM;
3187 		tf->hob_nsect = (size / 512) >> 8;
3188 		tf->nsect = size / 512;
3189 		tf->command = ATA_CMD_DSM;
3190 	}
3191 
3192 	tf->flags |= ATA_TFLAG_ISADDR | ATA_TFLAG_DEVICE | ATA_TFLAG_LBA48 |
3193 		     ATA_TFLAG_WRITE;
3194 
3195 	ata_qc_set_pc_nbytes(qc);
3196 
3197 	return 0;
3198 
3199  invalid_fld:
3200 	ata_scsi_set_sense(scmd, ILLEGAL_REQUEST, 0x24, 0x00);
3201 	/* "Invalid field in cdb" */
3202 	return 1;
3203 }
3204 
3205 /**
3206  *	ata_mselect_caching - Simulate MODE SELECT for caching info page
3207  *	@qc: Storage for translated ATA taskfile
3208  *	@buf: input buffer
3209  *	@len: number of valid bytes in the input buffer
3210  *
3211  *	Prepare a taskfile to modify caching information for the device.
3212  *
3213  *	LOCKING:
3214  *	None.
3215  */
3216 static int ata_mselect_caching(struct ata_queued_cmd *qc,
3217 			       const u8 *buf, int len)
3218 {
3219 	struct ata_taskfile *tf = &qc->tf;
3220 	struct ata_device *dev = qc->dev;
3221 	char mpage[CACHE_MPAGE_LEN];
3222 	u8 wce;
3223 
3224 	/*
3225 	 * The first two bytes of def_cache_mpage are a header, so offsets
3226 	 * in mpage are off by 2 compared to buf.  Same for len.
3227 	 */
3228 
3229 	if (len != CACHE_MPAGE_LEN - 2)
3230 		return -EINVAL;
3231 
3232 	wce = buf[0] & (1 << 2);
3233 
3234 	/*
3235 	 * Check that read-only bits are not modified.
3236 	 */
3237 	ata_msense_caching(dev->id, mpage, false);
3238 	mpage[2] &= ~(1 << 2);
3239 	mpage[2] |= wce;
3240 	if (memcmp(mpage + 2, buf, CACHE_MPAGE_LEN - 2) != 0)
3241 		return -EINVAL;
3242 
3243 	tf->flags |= ATA_TFLAG_DEVICE | ATA_TFLAG_ISADDR;
3244 	tf->protocol = ATA_PROT_NODATA;
3245 	tf->nsect = 0;
3246 	tf->command = ATA_CMD_SET_FEATURES;
3247 	tf->feature = wce ? SETFEATURES_WC_ON : SETFEATURES_WC_OFF;
3248 	return 0;
3249 }
3250 
3251 /**
3252  *	ata_scsiop_mode_select - Simulate MODE SELECT 6, 10 commands
3253  *	@qc: Storage for translated ATA taskfile
3254  *
3255  *	Converts a MODE SELECT command to an ATA SET FEATURES taskfile.
3256  *	Assume this is invoked for direct access devices (e.g. disks) only.
3257  *	There should be no block descriptor for other device types.
3258  *
3259  *	LOCKING:
3260  *	spin_lock_irqsave(host lock)
3261  */
3262 static unsigned int ata_scsi_mode_select_xlat(struct ata_queued_cmd *qc)
3263 {
3264 	struct scsi_cmnd *scmd = qc->scsicmd;
3265 	const u8 *cdb = scmd->cmnd;
3266 	const u8 *p;
3267 	u8 pg, spg;
3268 	unsigned six_byte, pg_len, hdr_len, bd_len;
3269 	int len;
3270 
3271 	VPRINTK("ENTER\n");
3272 
3273 	six_byte = (cdb[0] == MODE_SELECT);
3274 	if (six_byte) {
3275 		if (scmd->cmd_len < 5)
3276 			goto invalid_fld;
3277 
3278 		len = cdb[4];
3279 		hdr_len = 4;
3280 	} else {
3281 		if (scmd->cmd_len < 9)
3282 			goto invalid_fld;
3283 
3284 		len = (cdb[7] << 8) + cdb[8];
3285 		hdr_len = 8;
3286 	}
3287 
3288 	/* We only support PF=1, SP=0.  */
3289 	if ((cdb[1] & 0x11) != 0x10)
3290 		goto invalid_fld;
3291 
3292 	/* Test early for possible overrun.  */
3293 	if (!scsi_sg_count(scmd) || scsi_sglist(scmd)->length < len)
3294 		goto invalid_param_len;
3295 
3296 	p = page_address(sg_page(scsi_sglist(scmd)));
3297 
3298 	/* Move past header and block descriptors.  */
3299 	if (len < hdr_len)
3300 		goto invalid_param_len;
3301 
3302 	if (six_byte)
3303 		bd_len = p[3];
3304 	else
3305 		bd_len = (p[6] << 8) + p[7];
3306 
3307 	len -= hdr_len;
3308 	p += hdr_len;
3309 	if (len < bd_len)
3310 		goto invalid_param_len;
3311 	if (bd_len != 0 && bd_len != 8)
3312 		goto invalid_param;
3313 
3314 	len -= bd_len;
3315 	p += bd_len;
3316 	if (len == 0)
3317 		goto skip;
3318 
3319 	/* Parse both possible formats for the mode page headers.  */
3320 	pg = p[0] & 0x3f;
3321 	if (p[0] & 0x40) {
3322 		if (len < 4)
3323 			goto invalid_param_len;
3324 
3325 		spg = p[1];
3326 		pg_len = (p[2] << 8) | p[3];
3327 		p += 4;
3328 		len -= 4;
3329 	} else {
3330 		if (len < 2)
3331 			goto invalid_param_len;
3332 
3333 		spg = 0;
3334 		pg_len = p[1];
3335 		p += 2;
3336 		len -= 2;
3337 	}
3338 
3339 	/*
3340 	 * No mode subpages supported (yet) but asking for _all_
3341 	 * subpages may be valid
3342 	 */
3343 	if (spg && (spg != ALL_SUB_MPAGES))
3344 		goto invalid_param;
3345 	if (pg_len > len)
3346 		goto invalid_param_len;
3347 
3348 	switch (pg) {
3349 	case CACHE_MPAGE:
3350 		if (ata_mselect_caching(qc, p, pg_len) < 0)
3351 			goto invalid_param;
3352 		break;
3353 
3354 	default:		/* invalid page code */
3355 		goto invalid_param;
3356 	}
3357 
3358 	/*
3359 	 * Only one page has changeable data, so we only support setting one
3360 	 * page at a time.
3361 	 */
3362 	if (len > pg_len)
3363 		goto invalid_param;
3364 
3365 	return 0;
3366 
3367  invalid_fld:
3368 	/* "Invalid field in CDB" */
3369 	ata_scsi_set_sense(scmd, ILLEGAL_REQUEST, 0x24, 0x0);
3370 	return 1;
3371 
3372  invalid_param:
3373 	/* "Invalid field in parameter list" */
3374 	ata_scsi_set_sense(scmd, ILLEGAL_REQUEST, 0x26, 0x0);
3375 	return 1;
3376 
3377  invalid_param_len:
3378 	/* "Parameter list length error" */
3379 	ata_scsi_set_sense(scmd, ILLEGAL_REQUEST, 0x1a, 0x0);
3380 	return 1;
3381 
3382  skip:
3383 	scmd->result = SAM_STAT_GOOD;
3384 	return 1;
3385 }
3386 
3387 /**
3388  *	ata_get_xlat_func - check if SCSI to ATA translation is possible
3389  *	@dev: ATA device
3390  *	@cmd: SCSI command opcode to consider
3391  *
3392  *	Look up the SCSI command given, and determine whether the
3393  *	SCSI command is to be translated or simulated.
3394  *
3395  *	RETURNS:
3396  *	Pointer to translation function if possible, %NULL if not.
3397  */
3398 
3399 static inline ata_xlat_func_t ata_get_xlat_func(struct ata_device *dev, u8 cmd)
3400 {
3401 	switch (cmd) {
3402 	case READ_6:
3403 	case READ_10:
3404 	case READ_16:
3405 
3406 	case WRITE_6:
3407 	case WRITE_10:
3408 	case WRITE_16:
3409 		return ata_scsi_rw_xlat;
3410 
3411 	case WRITE_SAME_16:
3412 		return ata_scsi_write_same_xlat;
3413 
3414 	case SYNCHRONIZE_CACHE:
3415 		if (ata_try_flush_cache(dev))
3416 			return ata_scsi_flush_xlat;
3417 		break;
3418 
3419 	case VERIFY:
3420 	case VERIFY_16:
3421 		return ata_scsi_verify_xlat;
3422 
3423 	case ATA_12:
3424 	case ATA_16:
3425 		return ata_scsi_pass_thru;
3426 
3427 	case MODE_SELECT:
3428 	case MODE_SELECT_10:
3429 		return ata_scsi_mode_select_xlat;
3430 		break;
3431 
3432 	case START_STOP:
3433 		return ata_scsi_start_stop_xlat;
3434 	}
3435 
3436 	return NULL;
3437 }
3438 
3439 /**
3440  *	ata_scsi_dump_cdb - dump SCSI command contents to dmesg
3441  *	@ap: ATA port to which the command was being sent
3442  *	@cmd: SCSI command to dump
3443  *
3444  *	Prints the contents of a SCSI command via printk().
3445  */
3446 
3447 static inline void ata_scsi_dump_cdb(struct ata_port *ap,
3448 				     struct scsi_cmnd *cmd)
3449 {
3450 #ifdef ATA_DEBUG
3451 	struct scsi_device *scsidev = cmd->device;
3452 	u8 *scsicmd = cmd->cmnd;
3453 
3454 	DPRINTK("CDB (%u:%d,%d,%d) %02x %02x %02x %02x %02x %02x %02x %02x %02x\n",
3455 		ap->print_id,
3456 		scsidev->channel, scsidev->id, scsidev->lun,
3457 		scsicmd[0], scsicmd[1], scsicmd[2], scsicmd[3],
3458 		scsicmd[4], scsicmd[5], scsicmd[6], scsicmd[7],
3459 		scsicmd[8]);
3460 #endif
3461 }
3462 
3463 static inline int __ata_scsi_queuecmd(struct scsi_cmnd *scmd,
3464 				      struct ata_device *dev)
3465 {
3466 	u8 scsi_op = scmd->cmnd[0];
3467 	ata_xlat_func_t xlat_func;
3468 	int rc = 0;
3469 
3470 	if (dev->class == ATA_DEV_ATA || dev->class == ATA_DEV_ZAC) {
3471 		if (unlikely(!scmd->cmd_len || scmd->cmd_len > dev->cdb_len))
3472 			goto bad_cdb_len;
3473 
3474 		xlat_func = ata_get_xlat_func(dev, scsi_op);
3475 	} else {
3476 		if (unlikely(!scmd->cmd_len))
3477 			goto bad_cdb_len;
3478 
3479 		xlat_func = NULL;
3480 		if (likely((scsi_op != ATA_16) || !atapi_passthru16)) {
3481 			/* relay SCSI command to ATAPI device */
3482 			int len = COMMAND_SIZE(scsi_op);
3483 			if (unlikely(len > scmd->cmd_len || len > dev->cdb_len))
3484 				goto bad_cdb_len;
3485 
3486 			xlat_func = atapi_xlat;
3487 		} else {
3488 			/* ATA_16 passthru, treat as an ATA command */
3489 			if (unlikely(scmd->cmd_len > 16))
3490 				goto bad_cdb_len;
3491 
3492 			xlat_func = ata_get_xlat_func(dev, scsi_op);
3493 		}
3494 	}
3495 
3496 	if (xlat_func)
3497 		rc = ata_scsi_translate(dev, scmd, xlat_func);
3498 	else
3499 		ata_scsi_simulate(dev, scmd);
3500 
3501 	return rc;
3502 
3503  bad_cdb_len:
3504 	DPRINTK("bad CDB len=%u, scsi_op=0x%02x, max=%u\n",
3505 		scmd->cmd_len, scsi_op, dev->cdb_len);
3506 	scmd->result = DID_ERROR << 16;
3507 	scmd->scsi_done(scmd);
3508 	return 0;
3509 }
3510 
3511 /**
3512  *	ata_scsi_queuecmd - Issue SCSI cdb to libata-managed device
3513  *	@shost: SCSI host of command to be sent
3514  *	@cmd: SCSI command to be sent
3515  *
3516  *	In some cases, this function translates SCSI commands into
3517  *	ATA taskfiles, and queues the taskfiles to be sent to
3518  *	hardware.  In other cases, this function simulates a
3519  *	SCSI device by evaluating and responding to certain
3520  *	SCSI commands.  This creates the overall effect of
3521  *	ATA and ATAPI devices appearing as SCSI devices.
3522  *
3523  *	LOCKING:
3524  *	ATA host lock
3525  *
3526  *	RETURNS:
3527  *	Return value from __ata_scsi_queuecmd() if @cmd can be queued,
3528  *	0 otherwise.
3529  */
3530 int ata_scsi_queuecmd(struct Scsi_Host *shost, struct scsi_cmnd *cmd)
3531 {
3532 	struct ata_port *ap;
3533 	struct ata_device *dev;
3534 	struct scsi_device *scsidev = cmd->device;
3535 	int rc = 0;
3536 	unsigned long irq_flags;
3537 
3538 	ap = ata_shost_to_port(shost);
3539 
3540 	spin_lock_irqsave(ap->lock, irq_flags);
3541 
3542 	ata_scsi_dump_cdb(ap, cmd);
3543 
3544 	dev = ata_scsi_find_dev(ap, scsidev);
3545 	if (likely(dev))
3546 		rc = __ata_scsi_queuecmd(cmd, dev);
3547 	else {
3548 		cmd->result = (DID_BAD_TARGET << 16);
3549 		cmd->scsi_done(cmd);
3550 	}
3551 
3552 	spin_unlock_irqrestore(ap->lock, irq_flags);
3553 
3554 	return rc;
3555 }
3556 
3557 /**
3558  *	ata_scsi_simulate - simulate SCSI command on ATA device
3559  *	@dev: the target device
3560  *	@cmd: SCSI command being sent to device.
3561  *
3562  *	Interprets and directly executes a select list of SCSI commands
3563  *	that can be handled internally.
3564  *
3565  *	LOCKING:
3566  *	spin_lock_irqsave(host lock)
3567  */
3568 
3569 void ata_scsi_simulate(struct ata_device *dev, struct scsi_cmnd *cmd)
3570 {
3571 	struct ata_scsi_args args;
3572 	const u8 *scsicmd = cmd->cmnd;
3573 	u8 tmp8;
3574 
3575 	args.dev = dev;
3576 	args.id = dev->id;
3577 	args.cmd = cmd;
3578 	args.done = cmd->scsi_done;
3579 
3580 	switch(scsicmd[0]) {
3581 	/* TODO: worth improving? */
3582 	case FORMAT_UNIT:
3583 		ata_scsi_invalid_field(cmd);
3584 		break;
3585 
3586 	case INQUIRY:
3587 		if (scsicmd[1] & 2)	           /* is CmdDt set?  */
3588 			ata_scsi_invalid_field(cmd);
3589 		else if ((scsicmd[1] & 1) == 0)    /* is EVPD clear? */
3590 			ata_scsi_rbuf_fill(&args, ata_scsiop_inq_std);
3591 		else switch (scsicmd[2]) {
3592 		case 0x00:
3593 			ata_scsi_rbuf_fill(&args, ata_scsiop_inq_00);
3594 			break;
3595 		case 0x80:
3596 			ata_scsi_rbuf_fill(&args, ata_scsiop_inq_80);
3597 			break;
3598 		case 0x83:
3599 			ata_scsi_rbuf_fill(&args, ata_scsiop_inq_83);
3600 			break;
3601 		case 0x89:
3602 			ata_scsi_rbuf_fill(&args, ata_scsiop_inq_89);
3603 			break;
3604 		case 0xb0:
3605 			ata_scsi_rbuf_fill(&args, ata_scsiop_inq_b0);
3606 			break;
3607 		case 0xb1:
3608 			ata_scsi_rbuf_fill(&args, ata_scsiop_inq_b1);
3609 			break;
3610 		case 0xb2:
3611 			ata_scsi_rbuf_fill(&args, ata_scsiop_inq_b2);
3612 			break;
3613 		default:
3614 			ata_scsi_invalid_field(cmd);
3615 			break;
3616 		}
3617 		break;
3618 
3619 	case MODE_SENSE:
3620 	case MODE_SENSE_10:
3621 		ata_scsi_rbuf_fill(&args, ata_scsiop_mode_sense);
3622 		break;
3623 
3624 	case READ_CAPACITY:
3625 		ata_scsi_rbuf_fill(&args, ata_scsiop_read_cap);
3626 		break;
3627 
3628 	case SERVICE_ACTION_IN_16:
3629 		if ((scsicmd[1] & 0x1f) == SAI_READ_CAPACITY_16)
3630 			ata_scsi_rbuf_fill(&args, ata_scsiop_read_cap);
3631 		else
3632 			ata_scsi_invalid_field(cmd);
3633 		break;
3634 
3635 	case REPORT_LUNS:
3636 		ata_scsi_rbuf_fill(&args, ata_scsiop_report_luns);
3637 		break;
3638 
3639 	case REQUEST_SENSE:
3640 		ata_scsi_set_sense(cmd, 0, 0, 0);
3641 		cmd->result = (DRIVER_SENSE << 24);
3642 		cmd->scsi_done(cmd);
3643 		break;
3644 
3645 	/* if we reach this, then writeback caching is disabled,
3646 	 * turning this into a no-op.
3647 	 */
3648 	case SYNCHRONIZE_CACHE:
3649 		/* fall through */
3650 
3651 	/* no-op's, complete with success */
3652 	case REZERO_UNIT:
3653 	case SEEK_6:
3654 	case SEEK_10:
3655 	case TEST_UNIT_READY:
3656 		ata_scsi_rbuf_fill(&args, ata_scsiop_noop);
3657 		break;
3658 
3659 	case SEND_DIAGNOSTIC:
3660 		tmp8 = scsicmd[1] & ~(1 << 3);
3661 		if ((tmp8 == 0x4) && (!scsicmd[3]) && (!scsicmd[4]))
3662 			ata_scsi_rbuf_fill(&args, ata_scsiop_noop);
3663 		else
3664 			ata_scsi_invalid_field(cmd);
3665 		break;
3666 
3667 	/* all other commands */
3668 	default:
3669 		ata_scsi_set_sense(cmd, ILLEGAL_REQUEST, 0x20, 0x0);
3670 		/* "Invalid command operation code" */
3671 		cmd->scsi_done(cmd);
3672 		break;
3673 	}
3674 }
3675 
3676 int ata_scsi_add_hosts(struct ata_host *host, struct scsi_host_template *sht)
3677 {
3678 	int i, rc;
3679 
3680 	for (i = 0; i < host->n_ports; i++) {
3681 		struct ata_port *ap = host->ports[i];
3682 		struct Scsi_Host *shost;
3683 
3684 		rc = -ENOMEM;
3685 		shost = scsi_host_alloc(sht, sizeof(struct ata_port *));
3686 		if (!shost)
3687 			goto err_alloc;
3688 
3689 		shost->eh_noresume = 1;
3690 		*(struct ata_port **)&shost->hostdata[0] = ap;
3691 		ap->scsi_host = shost;
3692 
3693 		shost->transportt = ata_scsi_transport_template;
3694 		shost->unique_id = ap->print_id;
3695 		shost->max_id = 16;
3696 		shost->max_lun = 1;
3697 		shost->max_channel = 1;
3698 		shost->max_cmd_len = 16;
3699 		shost->no_write_same = 1;
3700 
3701 		/* Schedule policy is determined by ->qc_defer()
3702 		 * callback and it needs to see every deferred qc.
3703 		 * Set host_blocked to 1 to prevent SCSI midlayer from
3704 		 * automatically deferring requests.
3705 		 */
3706 		shost->max_host_blocked = 1;
3707 
3708 		if (scsi_init_shared_tag_map(shost, host->n_tags))
3709 			goto err_add;
3710 
3711 		rc = scsi_add_host_with_dma(ap->scsi_host,
3712 						&ap->tdev, ap->host->dev);
3713 		if (rc)
3714 			goto err_add;
3715 	}
3716 
3717 	return 0;
3718 
3719  err_add:
3720 	scsi_host_put(host->ports[i]->scsi_host);
3721  err_alloc:
3722 	while (--i >= 0) {
3723 		struct Scsi_Host *shost = host->ports[i]->scsi_host;
3724 
3725 		scsi_remove_host(shost);
3726 		scsi_host_put(shost);
3727 	}
3728 	return rc;
3729 }
3730 
3731 void ata_scsi_scan_host(struct ata_port *ap, int sync)
3732 {
3733 	int tries = 5;
3734 	struct ata_device *last_failed_dev = NULL;
3735 	struct ata_link *link;
3736 	struct ata_device *dev;
3737 
3738  repeat:
3739 	ata_for_each_link(link, ap, EDGE) {
3740 		ata_for_each_dev(dev, link, ENABLED) {
3741 			struct scsi_device *sdev;
3742 			int channel = 0, id = 0;
3743 
3744 			if (dev->sdev)
3745 				continue;
3746 
3747 			if (ata_is_host_link(link))
3748 				id = dev->devno;
3749 			else
3750 				channel = link->pmp;
3751 
3752 			sdev = __scsi_add_device(ap->scsi_host, channel, id, 0,
3753 						 NULL);
3754 			if (!IS_ERR(sdev)) {
3755 				dev->sdev = sdev;
3756 				scsi_device_put(sdev);
3757 			} else {
3758 				dev->sdev = NULL;
3759 			}
3760 		}
3761 	}
3762 
3763 	/* If we scanned while EH was in progress or allocation
3764 	 * failure occurred, scan would have failed silently.  Check
3765 	 * whether all devices are attached.
3766 	 */
3767 	ata_for_each_link(link, ap, EDGE) {
3768 		ata_for_each_dev(dev, link, ENABLED) {
3769 			if (!dev->sdev)
3770 				goto exit_loop;
3771 		}
3772 	}
3773  exit_loop:
3774 	if (!link)
3775 		return;
3776 
3777 	/* we're missing some SCSI devices */
3778 	if (sync) {
3779 		/* If caller requested synchrnous scan && we've made
3780 		 * any progress, sleep briefly and repeat.
3781 		 */
3782 		if (dev != last_failed_dev) {
3783 			msleep(100);
3784 			last_failed_dev = dev;
3785 			goto repeat;
3786 		}
3787 
3788 		/* We might be failing to detect boot device, give it
3789 		 * a few more chances.
3790 		 */
3791 		if (--tries) {
3792 			msleep(100);
3793 			goto repeat;
3794 		}
3795 
3796 		ata_port_err(ap,
3797 			     "WARNING: synchronous SCSI scan failed without making any progress, switching to async\n");
3798 	}
3799 
3800 	queue_delayed_work(system_long_wq, &ap->hotplug_task,
3801 			   round_jiffies_relative(HZ));
3802 }
3803 
3804 /**
3805  *	ata_scsi_offline_dev - offline attached SCSI device
3806  *	@dev: ATA device to offline attached SCSI device for
3807  *
3808  *	This function is called from ata_eh_hotplug() and responsible
3809  *	for taking the SCSI device attached to @dev offline.  This
3810  *	function is called with host lock which protects dev->sdev
3811  *	against clearing.
3812  *
3813  *	LOCKING:
3814  *	spin_lock_irqsave(host lock)
3815  *
3816  *	RETURNS:
3817  *	1 if attached SCSI device exists, 0 otherwise.
3818  */
3819 int ata_scsi_offline_dev(struct ata_device *dev)
3820 {
3821 	if (dev->sdev) {
3822 		scsi_device_set_state(dev->sdev, SDEV_OFFLINE);
3823 		return 1;
3824 	}
3825 	return 0;
3826 }
3827 
3828 /**
3829  *	ata_scsi_remove_dev - remove attached SCSI device
3830  *	@dev: ATA device to remove attached SCSI device for
3831  *
3832  *	This function is called from ata_eh_scsi_hotplug() and
3833  *	responsible for removing the SCSI device attached to @dev.
3834  *
3835  *	LOCKING:
3836  *	Kernel thread context (may sleep).
3837  */
3838 static void ata_scsi_remove_dev(struct ata_device *dev)
3839 {
3840 	struct ata_port *ap = dev->link->ap;
3841 	struct scsi_device *sdev;
3842 	unsigned long flags;
3843 
3844 	/* Alas, we need to grab scan_mutex to ensure SCSI device
3845 	 * state doesn't change underneath us and thus
3846 	 * scsi_device_get() always succeeds.  The mutex locking can
3847 	 * be removed if there is __scsi_device_get() interface which
3848 	 * increments reference counts regardless of device state.
3849 	 */
3850 	mutex_lock(&ap->scsi_host->scan_mutex);
3851 	spin_lock_irqsave(ap->lock, flags);
3852 
3853 	/* clearing dev->sdev is protected by host lock */
3854 	sdev = dev->sdev;
3855 	dev->sdev = NULL;
3856 
3857 	if (sdev) {
3858 		/* If user initiated unplug races with us, sdev can go
3859 		 * away underneath us after the host lock and
3860 		 * scan_mutex are released.  Hold onto it.
3861 		 */
3862 		if (scsi_device_get(sdev) == 0) {
3863 			/* The following ensures the attached sdev is
3864 			 * offline on return from ata_scsi_offline_dev()
3865 			 * regardless it wins or loses the race
3866 			 * against this function.
3867 			 */
3868 			scsi_device_set_state(sdev, SDEV_OFFLINE);
3869 		} else {
3870 			WARN_ON(1);
3871 			sdev = NULL;
3872 		}
3873 	}
3874 
3875 	spin_unlock_irqrestore(ap->lock, flags);
3876 	mutex_unlock(&ap->scsi_host->scan_mutex);
3877 
3878 	if (sdev) {
3879 		ata_dev_info(dev, "detaching (SCSI %s)\n",
3880 			     dev_name(&sdev->sdev_gendev));
3881 
3882 		scsi_remove_device(sdev);
3883 		scsi_device_put(sdev);
3884 	}
3885 }
3886 
3887 static void ata_scsi_handle_link_detach(struct ata_link *link)
3888 {
3889 	struct ata_port *ap = link->ap;
3890 	struct ata_device *dev;
3891 
3892 	ata_for_each_dev(dev, link, ALL) {
3893 		unsigned long flags;
3894 
3895 		if (!(dev->flags & ATA_DFLAG_DETACHED))
3896 			continue;
3897 
3898 		spin_lock_irqsave(ap->lock, flags);
3899 		dev->flags &= ~ATA_DFLAG_DETACHED;
3900 		spin_unlock_irqrestore(ap->lock, flags);
3901 
3902 		if (zpodd_dev_enabled(dev))
3903 			zpodd_exit(dev);
3904 
3905 		ata_scsi_remove_dev(dev);
3906 	}
3907 }
3908 
3909 /**
3910  *	ata_scsi_media_change_notify - send media change event
3911  *	@dev: Pointer to the disk device with media change event
3912  *
3913  *	Tell the block layer to send a media change notification
3914  *	event.
3915  *
3916  * 	LOCKING:
3917  * 	spin_lock_irqsave(host lock)
3918  */
3919 void ata_scsi_media_change_notify(struct ata_device *dev)
3920 {
3921 	if (dev->sdev)
3922 		sdev_evt_send_simple(dev->sdev, SDEV_EVT_MEDIA_CHANGE,
3923 				     GFP_ATOMIC);
3924 }
3925 
3926 /**
3927  *	ata_scsi_hotplug - SCSI part of hotplug
3928  *	@work: Pointer to ATA port to perform SCSI hotplug on
3929  *
3930  *	Perform SCSI part of hotplug.  It's executed from a separate
3931  *	workqueue after EH completes.  This is necessary because SCSI
3932  *	hot plugging requires working EH and hot unplugging is
3933  *	synchronized with hot plugging with a mutex.
3934  *
3935  *	LOCKING:
3936  *	Kernel thread context (may sleep).
3937  */
3938 void ata_scsi_hotplug(struct work_struct *work)
3939 {
3940 	struct ata_port *ap =
3941 		container_of(work, struct ata_port, hotplug_task.work);
3942 	int i;
3943 
3944 	if (ap->pflags & ATA_PFLAG_UNLOADING) {
3945 		DPRINTK("ENTER/EXIT - unloading\n");
3946 		return;
3947 	}
3948 
3949 	/*
3950 	 * XXX - UGLY HACK
3951 	 *
3952 	 * The block layer suspend/resume path is fundamentally broken due
3953 	 * to freezable kthreads and workqueue and may deadlock if a block
3954 	 * device gets removed while resume is in progress.  I don't know
3955 	 * what the solution is short of removing freezable kthreads and
3956 	 * workqueues altogether.
3957 	 *
3958 	 * The following is an ugly hack to avoid kicking off device
3959 	 * removal while freezer is active.  This is a joke but does avoid
3960 	 * this particular deadlock scenario.
3961 	 *
3962 	 * https://bugzilla.kernel.org/show_bug.cgi?id=62801
3963 	 * http://marc.info/?l=linux-kernel&m=138695698516487
3964 	 */
3965 #ifdef CONFIG_FREEZER
3966 	while (pm_freezing)
3967 		msleep(10);
3968 #endif
3969 
3970 	DPRINTK("ENTER\n");
3971 	mutex_lock(&ap->scsi_scan_mutex);
3972 
3973 	/* Unplug detached devices.  We cannot use link iterator here
3974 	 * because PMP links have to be scanned even if PMP is
3975 	 * currently not attached.  Iterate manually.
3976 	 */
3977 	ata_scsi_handle_link_detach(&ap->link);
3978 	if (ap->pmp_link)
3979 		for (i = 0; i < SATA_PMP_MAX_PORTS; i++)
3980 			ata_scsi_handle_link_detach(&ap->pmp_link[i]);
3981 
3982 	/* scan for new ones */
3983 	ata_scsi_scan_host(ap, 0);
3984 
3985 	mutex_unlock(&ap->scsi_scan_mutex);
3986 	DPRINTK("EXIT\n");
3987 }
3988 
3989 /**
3990  *	ata_scsi_user_scan - indication for user-initiated bus scan
3991  *	@shost: SCSI host to scan
3992  *	@channel: Channel to scan
3993  *	@id: ID to scan
3994  *	@lun: LUN to scan
3995  *
3996  *	This function is called when user explicitly requests bus
3997  *	scan.  Set probe pending flag and invoke EH.
3998  *
3999  *	LOCKING:
4000  *	SCSI layer (we don't care)
4001  *
4002  *	RETURNS:
4003  *	Zero.
4004  */
4005 int ata_scsi_user_scan(struct Scsi_Host *shost, unsigned int channel,
4006 		       unsigned int id, u64 lun)
4007 {
4008 	struct ata_port *ap = ata_shost_to_port(shost);
4009 	unsigned long flags;
4010 	int devno, rc = 0;
4011 
4012 	if (!ap->ops->error_handler)
4013 		return -EOPNOTSUPP;
4014 
4015 	if (lun != SCAN_WILD_CARD && lun)
4016 		return -EINVAL;
4017 
4018 	if (!sata_pmp_attached(ap)) {
4019 		if (channel != SCAN_WILD_CARD && channel)
4020 			return -EINVAL;
4021 		devno = id;
4022 	} else {
4023 		if (id != SCAN_WILD_CARD && id)
4024 			return -EINVAL;
4025 		devno = channel;
4026 	}
4027 
4028 	spin_lock_irqsave(ap->lock, flags);
4029 
4030 	if (devno == SCAN_WILD_CARD) {
4031 		struct ata_link *link;
4032 
4033 		ata_for_each_link(link, ap, EDGE) {
4034 			struct ata_eh_info *ehi = &link->eh_info;
4035 			ehi->probe_mask |= ATA_ALL_DEVICES;
4036 			ehi->action |= ATA_EH_RESET;
4037 		}
4038 	} else {
4039 		struct ata_device *dev = ata_find_dev(ap, devno);
4040 
4041 		if (dev) {
4042 			struct ata_eh_info *ehi = &dev->link->eh_info;
4043 			ehi->probe_mask |= 1 << dev->devno;
4044 			ehi->action |= ATA_EH_RESET;
4045 		} else
4046 			rc = -EINVAL;
4047 	}
4048 
4049 	if (rc == 0) {
4050 		ata_port_schedule_eh(ap);
4051 		spin_unlock_irqrestore(ap->lock, flags);
4052 		ata_port_wait_eh(ap);
4053 	} else
4054 		spin_unlock_irqrestore(ap->lock, flags);
4055 
4056 	return rc;
4057 }
4058 
4059 /**
4060  *	ata_scsi_dev_rescan - initiate scsi_rescan_device()
4061  *	@work: Pointer to ATA port to perform scsi_rescan_device()
4062  *
4063  *	After ATA pass thru (SAT) commands are executed successfully,
4064  *	libata need to propagate the changes to SCSI layer.
4065  *
4066  *	LOCKING:
4067  *	Kernel thread context (may sleep).
4068  */
4069 void ata_scsi_dev_rescan(struct work_struct *work)
4070 {
4071 	struct ata_port *ap =
4072 		container_of(work, struct ata_port, scsi_rescan_task);
4073 	struct ata_link *link;
4074 	struct ata_device *dev;
4075 	unsigned long flags;
4076 
4077 	mutex_lock(&ap->scsi_scan_mutex);
4078 	spin_lock_irqsave(ap->lock, flags);
4079 
4080 	ata_for_each_link(link, ap, EDGE) {
4081 		ata_for_each_dev(dev, link, ENABLED) {
4082 			struct scsi_device *sdev = dev->sdev;
4083 
4084 			if (!sdev)
4085 				continue;
4086 			if (scsi_device_get(sdev))
4087 				continue;
4088 
4089 			spin_unlock_irqrestore(ap->lock, flags);
4090 			scsi_rescan_device(&(sdev->sdev_gendev));
4091 			scsi_device_put(sdev);
4092 			spin_lock_irqsave(ap->lock, flags);
4093 		}
4094 	}
4095 
4096 	spin_unlock_irqrestore(ap->lock, flags);
4097 	mutex_unlock(&ap->scsi_scan_mutex);
4098 }
4099 
4100 /**
4101  *	ata_sas_port_alloc - Allocate port for a SAS attached SATA device
4102  *	@host: ATA host container for all SAS ports
4103  *	@port_info: Information from low-level host driver
4104  *	@shost: SCSI host that the scsi device is attached to
4105  *
4106  *	LOCKING:
4107  *	PCI/etc. bus probe sem.
4108  *
4109  *	RETURNS:
4110  *	ata_port pointer on success / NULL on failure.
4111  */
4112 
4113 struct ata_port *ata_sas_port_alloc(struct ata_host *host,
4114 				    struct ata_port_info *port_info,
4115 				    struct Scsi_Host *shost)
4116 {
4117 	struct ata_port *ap;
4118 
4119 	ap = ata_port_alloc(host);
4120 	if (!ap)
4121 		return NULL;
4122 
4123 	ap->port_no = 0;
4124 	ap->lock = &host->lock;
4125 	ap->pio_mask = port_info->pio_mask;
4126 	ap->mwdma_mask = port_info->mwdma_mask;
4127 	ap->udma_mask = port_info->udma_mask;
4128 	ap->flags |= port_info->flags;
4129 	ap->ops = port_info->port_ops;
4130 	ap->cbl = ATA_CBL_SATA;
4131 
4132 	return ap;
4133 }
4134 EXPORT_SYMBOL_GPL(ata_sas_port_alloc);
4135 
4136 /**
4137  *	ata_sas_port_start - Set port up for dma.
4138  *	@ap: Port to initialize
4139  *
4140  *	Called just after data structures for each port are
4141  *	initialized.
4142  *
4143  *	May be used as the port_start() entry in ata_port_operations.
4144  *
4145  *	LOCKING:
4146  *	Inherited from caller.
4147  */
4148 int ata_sas_port_start(struct ata_port *ap)
4149 {
4150 	/*
4151 	 * the port is marked as frozen at allocation time, but if we don't
4152 	 * have new eh, we won't thaw it
4153 	 */
4154 	if (!ap->ops->error_handler)
4155 		ap->pflags &= ~ATA_PFLAG_FROZEN;
4156 	return 0;
4157 }
4158 EXPORT_SYMBOL_GPL(ata_sas_port_start);
4159 
4160 /**
4161  *	ata_port_stop - Undo ata_sas_port_start()
4162  *	@ap: Port to shut down
4163  *
4164  *	May be used as the port_stop() entry in ata_port_operations.
4165  *
4166  *	LOCKING:
4167  *	Inherited from caller.
4168  */
4169 
4170 void ata_sas_port_stop(struct ata_port *ap)
4171 {
4172 }
4173 EXPORT_SYMBOL_GPL(ata_sas_port_stop);
4174 
4175 /**
4176  * ata_sas_async_probe - simply schedule probing and return
4177  * @ap: Port to probe
4178  *
4179  * For batch scheduling of probe for sas attached ata devices, assumes
4180  * the port has already been through ata_sas_port_init()
4181  */
4182 void ata_sas_async_probe(struct ata_port *ap)
4183 {
4184 	__ata_port_probe(ap);
4185 }
4186 EXPORT_SYMBOL_GPL(ata_sas_async_probe);
4187 
4188 int ata_sas_sync_probe(struct ata_port *ap)
4189 {
4190 	return ata_port_probe(ap);
4191 }
4192 EXPORT_SYMBOL_GPL(ata_sas_sync_probe);
4193 
4194 
4195 /**
4196  *	ata_sas_port_init - Initialize a SATA device
4197  *	@ap: SATA port to initialize
4198  *
4199  *	LOCKING:
4200  *	PCI/etc. bus probe sem.
4201  *
4202  *	RETURNS:
4203  *	Zero on success, non-zero on error.
4204  */
4205 
4206 int ata_sas_port_init(struct ata_port *ap)
4207 {
4208 	int rc = ap->ops->port_start(ap);
4209 
4210 	if (rc)
4211 		return rc;
4212 	ap->print_id = atomic_inc_return(&ata_print_id);
4213 	return 0;
4214 }
4215 EXPORT_SYMBOL_GPL(ata_sas_port_init);
4216 
4217 /**
4218  *	ata_sas_port_destroy - Destroy a SATA port allocated by ata_sas_port_alloc
4219  *	@ap: SATA port to destroy
4220  *
4221  */
4222 
4223 void ata_sas_port_destroy(struct ata_port *ap)
4224 {
4225 	if (ap->ops->port_stop)
4226 		ap->ops->port_stop(ap);
4227 	kfree(ap);
4228 }
4229 EXPORT_SYMBOL_GPL(ata_sas_port_destroy);
4230 
4231 /**
4232  *	ata_sas_slave_configure - Default slave_config routine for libata devices
4233  *	@sdev: SCSI device to configure
4234  *	@ap: ATA port to which SCSI device is attached
4235  *
4236  *	RETURNS:
4237  *	Zero.
4238  */
4239 
4240 int ata_sas_slave_configure(struct scsi_device *sdev, struct ata_port *ap)
4241 {
4242 	ata_scsi_sdev_config(sdev);
4243 	ata_scsi_dev_config(sdev, ap->link.device);
4244 	return 0;
4245 }
4246 EXPORT_SYMBOL_GPL(ata_sas_slave_configure);
4247 
4248 /**
4249  *	ata_sas_queuecmd - Issue SCSI cdb to libata-managed device
4250  *	@cmd: SCSI command to be sent
4251  *	@ap:	ATA port to which the command is being sent
4252  *
4253  *	RETURNS:
4254  *	Return value from __ata_scsi_queuecmd() if @cmd can be queued,
4255  *	0 otherwise.
4256  */
4257 
4258 int ata_sas_queuecmd(struct scsi_cmnd *cmd, struct ata_port *ap)
4259 {
4260 	int rc = 0;
4261 
4262 	ata_scsi_dump_cdb(ap, cmd);
4263 
4264 	if (likely(ata_dev_enabled(ap->link.device)))
4265 		rc = __ata_scsi_queuecmd(cmd, ap->link.device);
4266 	else {
4267 		cmd->result = (DID_BAD_TARGET << 16);
4268 		cmd->scsi_done(cmd);
4269 	}
4270 	return rc;
4271 }
4272 EXPORT_SYMBOL_GPL(ata_sas_queuecmd);
4273 
4274 int ata_sas_allocate_tag(struct ata_port *ap)
4275 {
4276 	unsigned int max_queue = ap->host->n_tags;
4277 	unsigned int i, tag;
4278 
4279 	for (i = 0, tag = ap->sas_last_tag + 1; i < max_queue; i++, tag++) {
4280 		tag = tag < max_queue ? tag : 0;
4281 
4282 		/* the last tag is reserved for internal command. */
4283 		if (tag == ATA_TAG_INTERNAL)
4284 			continue;
4285 
4286 		if (!test_and_set_bit(tag, &ap->sas_tag_allocated)) {
4287 			ap->sas_last_tag = tag;
4288 			return tag;
4289 		}
4290 	}
4291 	return -1;
4292 }
4293 
4294 void ata_sas_free_tag(unsigned int tag, struct ata_port *ap)
4295 {
4296 	clear_bit(tag, &ap->sas_tag_allocated);
4297 }
4298