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
59static DEFINE_SPINLOCK(ata_scsi_rbuf_lock);
60static u8 ata_scsi_rbuf[ATA_SCSI_RBUF_SIZE];
61
62typedef unsigned int (*ata_xlat_func_t)(struct ata_queued_cmd *qc);
63
64static struct ata_device *__ata_scsi_find_dev(struct ata_port *ap,
65					const struct scsi_device *scsidev);
66static 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
79static 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
89static 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
98static 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
107static 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
114static 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);
149out_unlock:
150	spin_unlock_irqrestore(ap->lock, flags);
151	return count;
152}
153
154static 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}
166DEVICE_ATTR(link_power_management_policy, S_IRUGO | S_IWUSR,
167	    ata_scsi_lpm_show, ata_scsi_lpm_store);
168EXPORT_SYMBOL_GPL(dev_attr_link_power_management_policy);
169
170static 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
203unlock:
204	spin_unlock_irq(ap->lock);
205
206	return rc ? rc : snprintf(buf, 20, "%u\n", msecs);
207}
208
209static 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	}
264unlock:
265	spin_unlock_irqrestore(ap->lock, flags);
266
267	return rc ? rc : len;
268}
269DEVICE_ATTR(unload_heads, S_IRUGO | S_IWUSR,
270	    ata_scsi_park_show, ata_scsi_park_store);
271EXPORT_SYMBOL_GPL(dev_attr_unload_heads);
272
273static void ata_scsi_set_sense(struct scsi_cmnd *cmd, u8 sk, u8 asc, u8 ascq)
274{
275	cmd->result = (DRIVER_SENSE << 24) | SAM_STAT_CHECK_CONDITION;
276
277	scsi_build_sense_buffer(0, cmd->sense_buffer, sk, asc, ascq);
278}
279
280static ssize_t
281ata_scsi_em_message_store(struct device *dev, struct device_attribute *attr,
282			  const char *buf, size_t count)
283{
284	struct Scsi_Host *shost = class_to_shost(dev);
285	struct ata_port *ap = ata_shost_to_port(shost);
286	if (ap->ops->em_store && (ap->flags & ATA_FLAG_EM))
287		return ap->ops->em_store(ap, buf, count);
288	return -EINVAL;
289}
290
291static ssize_t
292ata_scsi_em_message_show(struct device *dev, struct device_attribute *attr,
293			 char *buf)
294{
295	struct Scsi_Host *shost = class_to_shost(dev);
296	struct ata_port *ap = ata_shost_to_port(shost);
297
298	if (ap->ops->em_show && (ap->flags & ATA_FLAG_EM))
299		return ap->ops->em_show(ap, buf);
300	return -EINVAL;
301}
302DEVICE_ATTR(em_message, S_IRUGO | S_IWUSR,
303		ata_scsi_em_message_show, ata_scsi_em_message_store);
304EXPORT_SYMBOL_GPL(dev_attr_em_message);
305
306static ssize_t
307ata_scsi_em_message_type_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	return snprintf(buf, 23, "%d\n", ap->em_message_type);
314}
315DEVICE_ATTR(em_message_type, S_IRUGO,
316		  ata_scsi_em_message_type_show, NULL);
317EXPORT_SYMBOL_GPL(dev_attr_em_message_type);
318
319static ssize_t
320ata_scsi_activity_show(struct device *dev, struct device_attribute *attr,
321		char *buf)
322{
323	struct scsi_device *sdev = to_scsi_device(dev);
324	struct ata_port *ap = ata_shost_to_port(sdev->host);
325	struct ata_device *atadev = ata_scsi_find_dev(ap, sdev);
326
327	if (atadev && ap->ops->sw_activity_show &&
328	    (ap->flags & ATA_FLAG_SW_ACTIVITY))
329		return ap->ops->sw_activity_show(atadev, buf);
330	return -EINVAL;
331}
332
333static ssize_t
334ata_scsi_activity_store(struct device *dev, struct device_attribute *attr,
335	const char *buf, size_t count)
336{
337	struct scsi_device *sdev = to_scsi_device(dev);
338	struct ata_port *ap = ata_shost_to_port(sdev->host);
339	struct ata_device *atadev = ata_scsi_find_dev(ap, sdev);
340	enum sw_activity val;
341	int rc;
342
343	if (atadev && ap->ops->sw_activity_store &&
344	    (ap->flags & ATA_FLAG_SW_ACTIVITY)) {
345		val = simple_strtoul(buf, NULL, 0);
346		switch (val) {
347		case OFF: case BLINK_ON: case BLINK_OFF:
348			rc = ap->ops->sw_activity_store(atadev, val);
349			if (!rc)
350				return count;
351			else
352				return rc;
353		}
354	}
355	return -EINVAL;
356}
357DEVICE_ATTR(sw_activity, S_IWUSR | S_IRUGO, ata_scsi_activity_show,
358			ata_scsi_activity_store);
359EXPORT_SYMBOL_GPL(dev_attr_sw_activity);
360
361struct device_attribute *ata_common_sdev_attrs[] = {
362	&dev_attr_unload_heads,
363	NULL
364};
365EXPORT_SYMBOL_GPL(ata_common_sdev_attrs);
366
367static void ata_scsi_invalid_field(struct scsi_cmnd *cmd)
368{
369	ata_scsi_set_sense(cmd, ILLEGAL_REQUEST, 0x24, 0x0);
370	/* "Invalid field in cbd" */
371	cmd->scsi_done(cmd);
372}
373
374/**
375 *	ata_std_bios_param - generic bios head/sector/cylinder calculator used by sd.
376 *	@sdev: SCSI device for which BIOS geometry is to be determined
377 *	@bdev: block device associated with @sdev
378 *	@capacity: capacity of SCSI device
379 *	@geom: location to which geometry will be output
380 *
381 *	Generic bios head/sector/cylinder calculator
382 *	used by sd. Most BIOSes nowadays expect a XXX/255/16  (CHS)
383 *	mapping. Some situations may arise where the disk is not
384 *	bootable if this is not used.
385 *
386 *	LOCKING:
387 *	Defined by the SCSI layer.  We don't really care.
388 *
389 *	RETURNS:
390 *	Zero.
391 */
392int ata_std_bios_param(struct scsi_device *sdev, struct block_device *bdev,
393		       sector_t capacity, int geom[])
394{
395	geom[0] = 255;
396	geom[1] = 63;
397	sector_div(capacity, 255*63);
398	geom[2] = capacity;
399
400	return 0;
401}
402
403/**
404 *	ata_scsi_unlock_native_capacity - unlock native capacity
405 *	@sdev: SCSI device to adjust device capacity for
406 *
407 *	This function is called if a partition on @sdev extends beyond
408 *	the end of the device.  It requests EH to unlock HPA.
409 *
410 *	LOCKING:
411 *	Defined by the SCSI layer.  Might sleep.
412 */
413void ata_scsi_unlock_native_capacity(struct scsi_device *sdev)
414{
415	struct ata_port *ap = ata_shost_to_port(sdev->host);
416	struct ata_device *dev;
417	unsigned long flags;
418
419	spin_lock_irqsave(ap->lock, flags);
420
421	dev = ata_scsi_find_dev(ap, sdev);
422	if (dev && dev->n_sectors < dev->n_native_sectors) {
423		dev->flags |= ATA_DFLAG_UNLOCK_HPA;
424		dev->link->eh_info.action |= ATA_EH_RESET;
425		ata_port_schedule_eh(ap);
426	}
427
428	spin_unlock_irqrestore(ap->lock, flags);
429	ata_port_wait_eh(ap);
430}
431
432/**
433 *	ata_get_identity - Handler for HDIO_GET_IDENTITY ioctl
434 *	@ap: target port
435 *	@sdev: SCSI device to get identify data for
436 *	@arg: User buffer area for identify data
437 *
438 *	LOCKING:
439 *	Defined by the SCSI layer.  We don't really care.
440 *
441 *	RETURNS:
442 *	Zero on success, negative errno on error.
443 */
444static int ata_get_identity(struct ata_port *ap, struct scsi_device *sdev,
445			    void __user *arg)
446{
447	struct ata_device *dev = ata_scsi_find_dev(ap, sdev);
448	u16 __user *dst = arg;
449	char buf[40];
450
451	if (!dev)
452		return -ENOMSG;
453
454	if (copy_to_user(dst, dev->id, ATA_ID_WORDS * sizeof(u16)))
455		return -EFAULT;
456
457	ata_id_string(dev->id, buf, ATA_ID_PROD, ATA_ID_PROD_LEN);
458	if (copy_to_user(dst + ATA_ID_PROD, buf, ATA_ID_PROD_LEN))
459		return -EFAULT;
460
461	ata_id_string(dev->id, buf, ATA_ID_FW_REV, ATA_ID_FW_REV_LEN);
462	if (copy_to_user(dst + ATA_ID_FW_REV, buf, ATA_ID_FW_REV_LEN))
463		return -EFAULT;
464
465	ata_id_string(dev->id, buf, ATA_ID_SERNO, ATA_ID_SERNO_LEN);
466	if (copy_to_user(dst + ATA_ID_SERNO, buf, ATA_ID_SERNO_LEN))
467		return -EFAULT;
468
469	return 0;
470}
471
472/**
473 *	ata_cmd_ioctl - Handler for HDIO_DRIVE_CMD ioctl
474 *	@scsidev: Device to which we are issuing command
475 *	@arg: User provided data for issuing command
476 *
477 *	LOCKING:
478 *	Defined by the SCSI layer.  We don't really care.
479 *
480 *	RETURNS:
481 *	Zero on success, negative errno on error.
482 */
483int ata_cmd_ioctl(struct scsi_device *scsidev, void __user *arg)
484{
485	int rc = 0;
486	u8 scsi_cmd[MAX_COMMAND_SIZE];
487	u8 args[4], *argbuf = NULL, *sensebuf = NULL;
488	int argsize = 0;
489	enum dma_data_direction data_dir;
490	int cmd_result;
491
492	if (arg == NULL)
493		return -EINVAL;
494
495	if (copy_from_user(args, arg, sizeof(args)))
496		return -EFAULT;
497
498	sensebuf = kzalloc(SCSI_SENSE_BUFFERSIZE, GFP_NOIO);
499	if (!sensebuf)
500		return -ENOMEM;
501
502	memset(scsi_cmd, 0, sizeof(scsi_cmd));
503
504	if (args[3]) {
505		argsize = ATA_SECT_SIZE * args[3];
506		argbuf = kmalloc(argsize, GFP_KERNEL);
507		if (argbuf == NULL) {
508			rc = -ENOMEM;
509			goto error;
510		}
511
512		scsi_cmd[1]  = (4 << 1); /* PIO Data-in */
513		scsi_cmd[2]  = 0x0e;     /* no off.line or cc, read from dev,
514					    block count in sector count field */
515		data_dir = DMA_FROM_DEVICE;
516	} else {
517		scsi_cmd[1]  = (3 << 1); /* Non-data */
518		scsi_cmd[2]  = 0x20;     /* cc but no off.line or data xfer */
519		data_dir = DMA_NONE;
520	}
521
522	scsi_cmd[0] = ATA_16;
523
524	scsi_cmd[4] = args[2];
525	if (args[0] == ATA_CMD_SMART) { /* hack -- ide driver does this too */
526		scsi_cmd[6]  = args[3];
527		scsi_cmd[8]  = args[1];
528		scsi_cmd[10] = 0x4f;
529		scsi_cmd[12] = 0xc2;
530	} else {
531		scsi_cmd[6]  = args[1];
532	}
533	scsi_cmd[14] = args[0];
534
535	/* Good values for timeout and retries?  Values below
536	   from scsi_ioctl_send_command() for default case... */
537	cmd_result = scsi_execute(scsidev, scsi_cmd, data_dir, argbuf, argsize,
538				  sensebuf, (10*HZ), 5, 0, NULL);
539
540	if (driver_byte(cmd_result) == DRIVER_SENSE) {/* sense data available */
541		u8 *desc = sensebuf + 8;
542		cmd_result &= ~(0xFF<<24); /* DRIVER_SENSE is not an error */
543
544		/* If we set cc then ATA pass-through will cause a
545		 * check condition even if no error. Filter that. */
546		if (cmd_result & SAM_STAT_CHECK_CONDITION) {
547			struct scsi_sense_hdr sshdr;
548			scsi_normalize_sense(sensebuf, SCSI_SENSE_BUFFERSIZE,
549					     &sshdr);
550			if (sshdr.sense_key == RECOVERED_ERROR &&
551			    sshdr.asc == 0 && sshdr.ascq == 0x1d)
552				cmd_result &= ~SAM_STAT_CHECK_CONDITION;
553		}
554
555		/* Send userspace a few ATA registers (same as drivers/ide) */
556		if (sensebuf[0] == 0x72 &&	/* format is "descriptor" */
557		    desc[0] == 0x09) {		/* code is "ATA Descriptor" */
558			args[0] = desc[13];	/* status */
559			args[1] = desc[3];	/* error */
560			args[2] = desc[5];	/* sector count (0:7) */
561			if (copy_to_user(arg, args, sizeof(args)))
562				rc = -EFAULT;
563		}
564	}
565
566
567	if (cmd_result) {
568		rc = -EIO;
569		goto error;
570	}
571
572	if ((argbuf)
573	 && copy_to_user(arg + sizeof(args), argbuf, argsize))
574		rc = -EFAULT;
575error:
576	kfree(sensebuf);
577	kfree(argbuf);
578	return rc;
579}
580
581/**
582 *	ata_task_ioctl - Handler for HDIO_DRIVE_TASK ioctl
583 *	@scsidev: Device to which we are issuing command
584 *	@arg: User provided data for issuing command
585 *
586 *	LOCKING:
587 *	Defined by the SCSI layer.  We don't really care.
588 *
589 *	RETURNS:
590 *	Zero on success, negative errno on error.
591 */
592int ata_task_ioctl(struct scsi_device *scsidev, void __user *arg)
593{
594	int rc = 0;
595	u8 scsi_cmd[MAX_COMMAND_SIZE];
596	u8 args[7], *sensebuf = NULL;
597	int cmd_result;
598
599	if (arg == NULL)
600		return -EINVAL;
601
602	if (copy_from_user(args, arg, sizeof(args)))
603		return -EFAULT;
604
605	sensebuf = kzalloc(SCSI_SENSE_BUFFERSIZE, GFP_NOIO);
606	if (!sensebuf)
607		return -ENOMEM;
608
609	memset(scsi_cmd, 0, sizeof(scsi_cmd));
610	scsi_cmd[0]  = ATA_16;
611	scsi_cmd[1]  = (3 << 1); /* Non-data */
612	scsi_cmd[2]  = 0x20;     /* cc but no off.line or data xfer */
613	scsi_cmd[4]  = args[1];
614	scsi_cmd[6]  = args[2];
615	scsi_cmd[8]  = args[3];
616	scsi_cmd[10] = args[4];
617	scsi_cmd[12] = args[5];
618	scsi_cmd[13] = args[6] & 0x4f;
619	scsi_cmd[14] = args[0];
620
621	/* Good values for timeout and retries?  Values below
622	   from scsi_ioctl_send_command() for default case... */
623	cmd_result = scsi_execute(scsidev, scsi_cmd, DMA_NONE, NULL, 0,
624				sensebuf, (10*HZ), 5, 0, NULL);
625
626	if (driver_byte(cmd_result) == DRIVER_SENSE) {/* sense data available */
627		u8 *desc = sensebuf + 8;
628		cmd_result &= ~(0xFF<<24); /* DRIVER_SENSE is not an error */
629
630		/* If we set cc then ATA pass-through will cause a
631		 * check condition even if no error. Filter that. */
632		if (cmd_result & SAM_STAT_CHECK_CONDITION) {
633			struct scsi_sense_hdr sshdr;
634			scsi_normalize_sense(sensebuf, SCSI_SENSE_BUFFERSIZE,
635						&sshdr);
636			if (sshdr.sense_key == RECOVERED_ERROR &&
637			    sshdr.asc == 0 && sshdr.ascq == 0x1d)
638				cmd_result &= ~SAM_STAT_CHECK_CONDITION;
639		}
640
641		/* Send userspace ATA registers */
642		if (sensebuf[0] == 0x72 &&	/* format is "descriptor" */
643				desc[0] == 0x09) {/* code is "ATA Descriptor" */
644			args[0] = desc[13];	/* status */
645			args[1] = desc[3];	/* error */
646			args[2] = desc[5];	/* sector count (0:7) */
647			args[3] = desc[7];	/* lbal */
648			args[4] = desc[9];	/* lbam */
649			args[5] = desc[11];	/* lbah */
650			args[6] = desc[12];	/* select */
651			if (copy_to_user(arg, args, sizeof(args)))
652				rc = -EFAULT;
653		}
654	}
655
656	if (cmd_result) {
657		rc = -EIO;
658		goto error;
659	}
660
661 error:
662	kfree(sensebuf);
663	return rc;
664}
665
666static int ata_ioc32(struct ata_port *ap)
667{
668	if (ap->flags & ATA_FLAG_PIO_DMA)
669		return 1;
670	if (ap->pflags & ATA_PFLAG_PIO32)
671		return 1;
672	return 0;
673}
674
675int ata_sas_scsi_ioctl(struct ata_port *ap, struct scsi_device *scsidev,
676		     int cmd, void __user *arg)
677{
678	unsigned long val;
679	int rc = -EINVAL;
680	unsigned long flags;
681
682	switch (cmd) {
683	case HDIO_GET_32BIT:
684		spin_lock_irqsave(ap->lock, flags);
685		val = ata_ioc32(ap);
686		spin_unlock_irqrestore(ap->lock, flags);
687		return put_user(val, (unsigned long __user *)arg);
688
689	case HDIO_SET_32BIT:
690		val = (unsigned long) arg;
691		rc = 0;
692		spin_lock_irqsave(ap->lock, flags);
693		if (ap->pflags & ATA_PFLAG_PIO32CHANGE) {
694			if (val)
695				ap->pflags |= ATA_PFLAG_PIO32;
696			else
697				ap->pflags &= ~ATA_PFLAG_PIO32;
698		} else {
699			if (val != ata_ioc32(ap))
700				rc = -EINVAL;
701		}
702		spin_unlock_irqrestore(ap->lock, flags);
703		return rc;
704
705	case HDIO_GET_IDENTITY:
706		return ata_get_identity(ap, scsidev, arg);
707
708	case HDIO_DRIVE_CMD:
709		if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
710			return -EACCES;
711		return ata_cmd_ioctl(scsidev, arg);
712
713	case HDIO_DRIVE_TASK:
714		if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
715			return -EACCES;
716		return ata_task_ioctl(scsidev, arg);
717
718	default:
719		rc = -ENOTTY;
720		break;
721	}
722
723	return rc;
724}
725EXPORT_SYMBOL_GPL(ata_sas_scsi_ioctl);
726
727int ata_scsi_ioctl(struct scsi_device *scsidev, int cmd, void __user *arg)
728{
729	return ata_sas_scsi_ioctl(ata_shost_to_port(scsidev->host),
730				scsidev, cmd, arg);
731}
732EXPORT_SYMBOL_GPL(ata_scsi_ioctl);
733
734/**
735 *	ata_scsi_qc_new - acquire new ata_queued_cmd reference
736 *	@dev: ATA device to which the new command is attached
737 *	@cmd: SCSI command that originated this ATA command
738 *
739 *	Obtain a reference to an unused ata_queued_cmd structure,
740 *	which is the basic libata structure representing a single
741 *	ATA command sent to the hardware.
742 *
743 *	If a command was available, fill in the SCSI-specific
744 *	portions of the structure with information on the
745 *	current command.
746 *
747 *	LOCKING:
748 *	spin_lock_irqsave(host lock)
749 *
750 *	RETURNS:
751 *	Command allocated, or %NULL if none available.
752 */
753static struct ata_queued_cmd *ata_scsi_qc_new(struct ata_device *dev,
754					      struct scsi_cmnd *cmd)
755{
756	struct ata_queued_cmd *qc;
757
758	qc = ata_qc_new_init(dev, cmd->request->tag);
759	if (qc) {
760		qc->scsicmd = cmd;
761		qc->scsidone = cmd->scsi_done;
762
763		qc->sg = scsi_sglist(cmd);
764		qc->n_elem = scsi_sg_count(cmd);
765	} else {
766		cmd->result = (DID_OK << 16) | (QUEUE_FULL << 1);
767		cmd->scsi_done(cmd);
768	}
769
770	return qc;
771}
772
773static void ata_qc_set_pc_nbytes(struct ata_queued_cmd *qc)
774{
775	struct scsi_cmnd *scmd = qc->scsicmd;
776
777	qc->extrabytes = scmd->request->extra_len;
778	qc->nbytes = scsi_bufflen(scmd) + qc->extrabytes;
779}
780
781/**
782 *	ata_dump_status - user friendly display of error info
783 *	@id: id of the port in question
784 *	@tf: ptr to filled out taskfile
785 *
786 *	Decode and dump the ATA error/status registers for the user so
787 *	that they have some idea what really happened at the non
788 *	make-believe layer.
789 *
790 *	LOCKING:
791 *	inherited from caller
792 */
793static void ata_dump_status(unsigned id, struct ata_taskfile *tf)
794{
795	u8 stat = tf->command, err = tf->feature;
796
797	printk(KERN_WARNING "ata%u: status=0x%02x { ", id, stat);
798	if (stat & ATA_BUSY) {
799		printk("Busy }\n");	/* Data is not valid in this case */
800	} else {
801		if (stat & ATA_DRDY)	printk("DriveReady ");
802		if (stat & ATA_DF)	printk("DeviceFault ");
803		if (stat & ATA_DSC)	printk("SeekComplete ");
804		if (stat & ATA_DRQ)	printk("DataRequest ");
805		if (stat & ATA_CORR)	printk("CorrectedError ");
806		if (stat & ATA_SENSE)	printk("Sense ");
807		if (stat & ATA_ERR)	printk("Error ");
808		printk("}\n");
809
810		if (err) {
811			printk(KERN_WARNING "ata%u: error=0x%02x { ", id, err);
812			if (err & ATA_ABORTED)	printk("DriveStatusError ");
813			if (err & ATA_ICRC) {
814				if (err & ATA_ABORTED)
815						printk("BadCRC ");
816				else		printk("Sector ");
817			}
818			if (err & ATA_UNC)	printk("UncorrectableError ");
819			if (err & ATA_IDNF)	printk("SectorIdNotFound ");
820			if (err & ATA_TRK0NF)	printk("TrackZeroNotFound ");
821			if (err & ATA_AMNF)	printk("AddrMarkNotFound ");
822			printk("}\n");
823		}
824	}
825}
826
827/**
828 *	ata_to_sense_error - convert ATA error to SCSI error
829 *	@id: ATA device number
830 *	@drv_stat: value contained in ATA status register
831 *	@drv_err: value contained in ATA error register
832 *	@sk: the sense key we'll fill out
833 *	@asc: the additional sense code we'll fill out
834 *	@ascq: the additional sense code qualifier we'll fill out
835 *	@verbose: be verbose
836 *
837 *	Converts an ATA error into a SCSI error.  Fill out pointers to
838 *	SK, ASC, and ASCQ bytes for later use in fixed or descriptor
839 *	format sense blocks.
840 *
841 *	LOCKING:
842 *	spin_lock_irqsave(host lock)
843 */
844static void ata_to_sense_error(unsigned id, u8 drv_stat, u8 drv_err, u8 *sk,
845			       u8 *asc, u8 *ascq, int verbose)
846{
847	int i;
848
849	/* Based on the 3ware driver translation table */
850	static const unsigned char sense_table[][4] = {
851		/* BBD|ECC|ID|MAR */
852		{0xd1,		ABORTED_COMMAND, 0x00, 0x00},
853			// Device busy                  Aborted command
854		/* BBD|ECC|ID */
855		{0xd0,		ABORTED_COMMAND, 0x00, 0x00},
856			// Device busy                  Aborted command
857		/* ECC|MC|MARK */
858		{0x61,		HARDWARE_ERROR, 0x00, 0x00},
859			// Device fault                 Hardware error
860		/* ICRC|ABRT */		/* NB: ICRC & !ABRT is BBD */
861		{0x84,		ABORTED_COMMAND, 0x47, 0x00},
862			// Data CRC error               SCSI parity error
863		/* MC|ID|ABRT|TRK0|MARK */
864		{0x37,		NOT_READY, 0x04, 0x00},
865			// Unit offline                 Not ready
866		/* MCR|MARK */
867		{0x09,		NOT_READY, 0x04, 0x00},
868			// Unrecovered disk error       Not ready
869		/*  Bad address mark */
870		{0x01,		MEDIUM_ERROR, 0x13, 0x00},
871			// Address mark not found for data field
872		/* TRK0 - Track 0 not found */
873		{0x02,		HARDWARE_ERROR, 0x00, 0x00},
874			// Hardware error
875		/* Abort: 0x04 is not translated here, see below */
876		/* Media change request */
877		{0x08,		NOT_READY, 0x04, 0x00},
878			// FIXME: faking offline
879		/* SRV/IDNF - ID not found */
880		{0x10,		ILLEGAL_REQUEST, 0x21, 0x00},
881			// Logical address out of range
882		/* MC - Media Changed */
883		{0x20,		UNIT_ATTENTION, 0x28, 0x00},
884			// Not ready to ready change, medium may have changed
885		/* ECC - Uncorrectable ECC error */
886		{0x40,		MEDIUM_ERROR, 0x11, 0x04},
887			// Unrecovered read error
888		/* BBD - block marked bad */
889		{0x80,		MEDIUM_ERROR, 0x11, 0x04},
890			// Block marked bad	Medium error, unrecovered read error
891		{0xFF, 0xFF, 0xFF, 0xFF}, // END mark
892	};
893	static const unsigned char stat_table[][4] = {
894		/* Must be first because BUSY means no other bits valid */
895		{0x80,		ABORTED_COMMAND, 0x47, 0x00},
896		// Busy, fake parity for now
897		{0x40,		ILLEGAL_REQUEST, 0x21, 0x04},
898		// Device ready, unaligned write command
899		{0x20,		HARDWARE_ERROR,  0x44, 0x00},
900		// Device fault, internal target failure
901		{0x08,		ABORTED_COMMAND, 0x47, 0x00},
902		// Timed out in xfer, fake parity for now
903		{0x04,		RECOVERED_ERROR, 0x11, 0x00},
904		// Recovered ECC error	  Medium error, recovered
905		{0xFF, 0xFF, 0xFF, 0xFF}, // END mark
906	};
907
908	/*
909	 *	Is this an error we can process/parse
910	 */
911	if (drv_stat & ATA_BUSY) {
912		drv_err = 0;	/* Ignore the err bits, they're invalid */
913	}
914
915	if (drv_err) {
916		/* Look for drv_err */
917		for (i = 0; sense_table[i][0] != 0xFF; i++) {
918			/* Look for best matches first */
919			if ((sense_table[i][0] & drv_err) ==
920			    sense_table[i][0]) {
921				*sk = sense_table[i][1];
922				*asc = sense_table[i][2];
923				*ascq = sense_table[i][3];
924				goto translate_done;
925			}
926		}
927	}
928
929	/*
930	 * Fall back to interpreting status bits.  Note that if the drv_err
931	 * has only the ABRT bit set, we decode drv_stat.  ABRT by itself
932	 * is not descriptive enough.
933	 */
934	for (i = 0; stat_table[i][0] != 0xFF; i++) {
935		if (stat_table[i][0] & drv_stat) {
936			*sk = stat_table[i][1];
937			*asc = stat_table[i][2];
938			*ascq = stat_table[i][3];
939			goto translate_done;
940		}
941	}
942
943	/*
944	 * We need a sensible error return here, which is tricky, and one
945	 * that won't cause people to do things like return a disk wrongly.
946	 */
947	*sk = ABORTED_COMMAND;
948	*asc = 0x00;
949	*ascq = 0x00;
950
951 translate_done:
952	if (verbose)
953		printk(KERN_ERR "ata%u: translated ATA stat/err 0x%02x/%02x "
954		       "to SCSI SK/ASC/ASCQ 0x%x/%02x/%02x\n",
955		       id, drv_stat, drv_err, *sk, *asc, *ascq);
956	return;
957}
958
959/*
960 *	ata_gen_passthru_sense - Generate check condition sense block.
961 *	@qc: Command that completed.
962 *
963 *	This function is specific to the ATA descriptor format sense
964 *	block specified for the ATA pass through commands.  Regardless
965 *	of whether the command errored or not, return a sense
966 *	block. Copy all controller registers into the sense
967 *	block. If there was no error, we get the request from an ATA
968 *	passthrough command, so we use the following sense data:
969 *	sk = RECOVERED ERROR
970 *	asc,ascq = ATA PASS-THROUGH INFORMATION AVAILABLE
971 *
972 *
973 *	LOCKING:
974 *	None.
975 */
976static void ata_gen_passthru_sense(struct ata_queued_cmd *qc)
977{
978	struct scsi_cmnd *cmd = qc->scsicmd;
979	struct ata_taskfile *tf = &qc->result_tf;
980	unsigned char *sb = cmd->sense_buffer;
981	unsigned char *desc = sb + 8;
982	int verbose = qc->ap->ops->error_handler == NULL;
983
984	memset(sb, 0, SCSI_SENSE_BUFFERSIZE);
985
986	cmd->result = (DRIVER_SENSE << 24) | SAM_STAT_CHECK_CONDITION;
987
988	/*
989	 * Use ata_to_sense_error() to map status register bits
990	 * onto sense key, asc & ascq.
991	 */
992	if (qc->err_mask ||
993	    tf->command & (ATA_BUSY | ATA_DF | ATA_ERR | ATA_DRQ)) {
994		ata_to_sense_error(qc->ap->print_id, tf->command, tf->feature,
995				   &sb[1], &sb[2], &sb[3], verbose);
996		sb[1] &= 0x0f;
997	} else {
998		sb[1] = RECOVERED_ERROR;
999		sb[2] = 0;
1000		sb[3] = 0x1D;
1001	}
1002
1003	/*
1004	 * Sense data is current and format is descriptor.
1005	 */
1006	sb[0] = 0x72;
1007
1008	desc[0] = 0x09;
1009
1010	/* set length of additional sense data */
1011	sb[7] = 14;
1012	desc[1] = 12;
1013
1014	/*
1015	 * Copy registers into sense buffer.
1016	 */
1017	desc[2] = 0x00;
1018	desc[3] = tf->feature;	/* == error reg */
1019	desc[5] = tf->nsect;
1020	desc[7] = tf->lbal;
1021	desc[9] = tf->lbam;
1022	desc[11] = tf->lbah;
1023	desc[12] = tf->device;
1024	desc[13] = tf->command; /* == status reg */
1025
1026	/*
1027	 * Fill in Extend bit, and the high order bytes
1028	 * if applicable.
1029	 */
1030	if (tf->flags & ATA_TFLAG_LBA48) {
1031		desc[2] |= 0x01;
1032		desc[4] = tf->hob_nsect;
1033		desc[6] = tf->hob_lbal;
1034		desc[8] = tf->hob_lbam;
1035		desc[10] = tf->hob_lbah;
1036	}
1037}
1038
1039/**
1040 *	ata_gen_ata_sense - generate a SCSI fixed sense block
1041 *	@qc: Command that we are erroring out
1042 *
1043 *	Generate sense block for a failed ATA command @qc.  Descriptor
1044 *	format is used to accommodate LBA48 block address.
1045 *
1046 *	LOCKING:
1047 *	None.
1048 */
1049static void ata_gen_ata_sense(struct ata_queued_cmd *qc)
1050{
1051	struct ata_device *dev = qc->dev;
1052	struct scsi_cmnd *cmd = qc->scsicmd;
1053	struct ata_taskfile *tf = &qc->result_tf;
1054	unsigned char *sb = cmd->sense_buffer;
1055	unsigned char *desc = sb + 8;
1056	int verbose = qc->ap->ops->error_handler == NULL;
1057	u64 block;
1058
1059	memset(sb, 0, SCSI_SENSE_BUFFERSIZE);
1060
1061	cmd->result = (DRIVER_SENSE << 24) | SAM_STAT_CHECK_CONDITION;
1062
1063	/* sense data is current and format is descriptor */
1064	sb[0] = 0x72;
1065
1066	/* Use ata_to_sense_error() to map status register bits
1067	 * onto sense key, asc & ascq.
1068	 */
1069	if (qc->err_mask ||
1070	    tf->command & (ATA_BUSY | ATA_DF | ATA_ERR | ATA_DRQ)) {
1071		ata_to_sense_error(qc->ap->print_id, tf->command, tf->feature,
1072				   &sb[1], &sb[2], &sb[3], verbose);
1073		sb[1] &= 0x0f;
1074	}
1075
1076	block = ata_tf_read_block(&qc->result_tf, dev);
1077
1078	/* information sense data descriptor */
1079	sb[7] = 12;
1080	desc[0] = 0x00;
1081	desc[1] = 10;
1082
1083	desc[2] |= 0x80;	/* valid */
1084	desc[6] = block >> 40;
1085	desc[7] = block >> 32;
1086	desc[8] = block >> 24;
1087	desc[9] = block >> 16;
1088	desc[10] = block >> 8;
1089	desc[11] = block;
1090}
1091
1092static void ata_scsi_sdev_config(struct scsi_device *sdev)
1093{
1094	sdev->use_10_for_rw = 1;
1095	sdev->use_10_for_ms = 1;
1096	sdev->no_report_opcodes = 1;
1097	sdev->no_write_same = 1;
1098
1099	/* Schedule policy is determined by ->qc_defer() callback and
1100	 * it needs to see every deferred qc.  Set dev_blocked to 1 to
1101	 * prevent SCSI midlayer from automatically deferring
1102	 * requests.
1103	 */
1104	sdev->max_device_blocked = 1;
1105}
1106
1107/**
1108 *	atapi_drain_needed - Check whether data transfer may overflow
1109 *	@rq: request to be checked
1110 *
1111 *	ATAPI commands which transfer variable length data to host
1112 *	might overflow due to application error or hardare bug.  This
1113 *	function checks whether overflow should be drained and ignored
1114 *	for @request.
1115 *
1116 *	LOCKING:
1117 *	None.
1118 *
1119 *	RETURNS:
1120 *	1 if ; otherwise, 0.
1121 */
1122static int atapi_drain_needed(struct request *rq)
1123{
1124	if (likely(rq->cmd_type != REQ_TYPE_BLOCK_PC))
1125		return 0;
1126
1127	if (!blk_rq_bytes(rq) || (rq->cmd_flags & REQ_WRITE))
1128		return 0;
1129
1130	return atapi_cmd_type(rq->cmd[0]) == ATAPI_MISC;
1131}
1132
1133static int ata_scsi_dev_config(struct scsi_device *sdev,
1134			       struct ata_device *dev)
1135{
1136	struct request_queue *q = sdev->request_queue;
1137
1138	if (!ata_id_has_unload(dev->id))
1139		dev->flags |= ATA_DFLAG_NO_UNLOAD;
1140
1141	/* configure max sectors */
1142	blk_queue_max_hw_sectors(q, dev->max_sectors);
1143
1144	if (dev->class == ATA_DEV_ATAPI) {
1145		void *buf;
1146
1147		sdev->sector_size = ATA_SECT_SIZE;
1148
1149		/* set DMA padding */
1150		blk_queue_update_dma_pad(q, ATA_DMA_PAD_SZ - 1);
1151
1152		/* configure draining */
1153		buf = kmalloc(ATAPI_MAX_DRAIN, q->bounce_gfp | GFP_KERNEL);
1154		if (!buf) {
1155			ata_dev_err(dev, "drain buffer allocation failed\n");
1156			return -ENOMEM;
1157		}
1158
1159		blk_queue_dma_drain(q, atapi_drain_needed, buf, ATAPI_MAX_DRAIN);
1160	} else {
1161		sdev->sector_size = ata_id_logical_sector_size(dev->id);
1162		sdev->manage_start_stop = 1;
1163	}
1164
1165	/*
1166	 * ata_pio_sectors() expects buffer for each sector to not cross
1167	 * page boundary.  Enforce it by requiring buffers to be sector
1168	 * aligned, which works iff sector_size is not larger than
1169	 * PAGE_SIZE.  ATAPI devices also need the alignment as
1170	 * IDENTIFY_PACKET is executed as ATA_PROT_PIO.
1171	 */
1172	if (sdev->sector_size > PAGE_SIZE)
1173		ata_dev_warn(dev,
1174			"sector_size=%u > PAGE_SIZE, PIO may malfunction\n",
1175			sdev->sector_size);
1176
1177	blk_queue_update_dma_alignment(q, sdev->sector_size - 1);
1178
1179	if (dev->flags & ATA_DFLAG_AN)
1180		set_bit(SDEV_EVT_MEDIA_CHANGE, sdev->supported_events);
1181
1182	if (dev->flags & ATA_DFLAG_NCQ) {
1183		int depth;
1184
1185		depth = min(sdev->host->can_queue, ata_id_queue_depth(dev->id));
1186		depth = min(ATA_MAX_QUEUE - 1, depth);
1187		scsi_change_queue_depth(sdev, depth);
1188	}
1189
1190	blk_queue_flush_queueable(q, false);
1191
1192	dev->sdev = sdev;
1193	return 0;
1194}
1195
1196/**
1197 *	ata_scsi_slave_config - Set SCSI device attributes
1198 *	@sdev: SCSI device to examine
1199 *
1200 *	This is called before we actually start reading
1201 *	and writing to the device, to configure certain
1202 *	SCSI mid-layer behaviors.
1203 *
1204 *	LOCKING:
1205 *	Defined by SCSI layer.  We don't really care.
1206 */
1207
1208int ata_scsi_slave_config(struct scsi_device *sdev)
1209{
1210	struct ata_port *ap = ata_shost_to_port(sdev->host);
1211	struct ata_device *dev = __ata_scsi_find_dev(ap, sdev);
1212	int rc = 0;
1213
1214	ata_scsi_sdev_config(sdev);
1215
1216	if (dev)
1217		rc = ata_scsi_dev_config(sdev, dev);
1218
1219	return rc;
1220}
1221
1222/**
1223 *	ata_scsi_slave_destroy - SCSI device is about to be destroyed
1224 *	@sdev: SCSI device to be destroyed
1225 *
1226 *	@sdev is about to be destroyed for hot/warm unplugging.  If
1227 *	this unplugging was initiated by libata as indicated by NULL
1228 *	dev->sdev, this function doesn't have to do anything.
1229 *	Otherwise, SCSI layer initiated warm-unplug is in progress.
1230 *	Clear dev->sdev, schedule the device for ATA detach and invoke
1231 *	EH.
1232 *
1233 *	LOCKING:
1234 *	Defined by SCSI layer.  We don't really care.
1235 */
1236void ata_scsi_slave_destroy(struct scsi_device *sdev)
1237{
1238	struct ata_port *ap = ata_shost_to_port(sdev->host);
1239	struct request_queue *q = sdev->request_queue;
1240	unsigned long flags;
1241	struct ata_device *dev;
1242
1243	if (!ap->ops->error_handler)
1244		return;
1245
1246	spin_lock_irqsave(ap->lock, flags);
1247	dev = __ata_scsi_find_dev(ap, sdev);
1248	if (dev && dev->sdev) {
1249		/* SCSI device already in CANCEL state, no need to offline it */
1250		dev->sdev = NULL;
1251		dev->flags |= ATA_DFLAG_DETACH;
1252		ata_port_schedule_eh(ap);
1253	}
1254	spin_unlock_irqrestore(ap->lock, flags);
1255
1256	kfree(q->dma_drain_buffer);
1257	q->dma_drain_buffer = NULL;
1258	q->dma_drain_size = 0;
1259}
1260
1261/**
1262 *	__ata_change_queue_depth - helper for ata_scsi_change_queue_depth
1263 *	@ap: ATA port to which the device change the queue depth
1264 *	@sdev: SCSI device to configure queue depth for
1265 *	@queue_depth: new queue depth
1266 *
1267 *	libsas and libata have different approaches for associating a sdev to
1268 *	its ata_port.
1269 *
1270 */
1271int __ata_change_queue_depth(struct ata_port *ap, struct scsi_device *sdev,
1272			     int queue_depth)
1273{
1274	struct ata_device *dev;
1275	unsigned long flags;
1276
1277	if (queue_depth < 1 || queue_depth == sdev->queue_depth)
1278		return sdev->queue_depth;
1279
1280	dev = ata_scsi_find_dev(ap, sdev);
1281	if (!dev || !ata_dev_enabled(dev))
1282		return sdev->queue_depth;
1283
1284	/* NCQ enabled? */
1285	spin_lock_irqsave(ap->lock, flags);
1286	dev->flags &= ~ATA_DFLAG_NCQ_OFF;
1287	if (queue_depth == 1 || !ata_ncq_enabled(dev)) {
1288		dev->flags |= ATA_DFLAG_NCQ_OFF;
1289		queue_depth = 1;
1290	}
1291	spin_unlock_irqrestore(ap->lock, flags);
1292
1293	/* limit and apply queue depth */
1294	queue_depth = min(queue_depth, sdev->host->can_queue);
1295	queue_depth = min(queue_depth, ata_id_queue_depth(dev->id));
1296	queue_depth = min(queue_depth, ATA_MAX_QUEUE - 1);
1297
1298	if (sdev->queue_depth == queue_depth)
1299		return -EINVAL;
1300
1301	return scsi_change_queue_depth(sdev, queue_depth);
1302}
1303
1304/**
1305 *	ata_scsi_change_queue_depth - SCSI callback for queue depth config
1306 *	@sdev: SCSI device to configure queue depth for
1307 *	@queue_depth: new queue depth
1308 *
1309 *	This is libata standard hostt->change_queue_depth callback.
1310 *	SCSI will call into this callback when user tries to set queue
1311 *	depth via sysfs.
1312 *
1313 *	LOCKING:
1314 *	SCSI layer (we don't care)
1315 *
1316 *	RETURNS:
1317 *	Newly configured queue depth.
1318 */
1319int ata_scsi_change_queue_depth(struct scsi_device *sdev, int queue_depth)
1320{
1321	struct ata_port *ap = ata_shost_to_port(sdev->host);
1322
1323	return __ata_change_queue_depth(ap, sdev, queue_depth);
1324}
1325
1326/**
1327 *	ata_scsi_start_stop_xlat - Translate SCSI START STOP UNIT command
1328 *	@qc: Storage for translated ATA taskfile
1329 *
1330 *	Sets up an ATA taskfile to issue STANDBY (to stop) or READ VERIFY
1331 *	(to start). Perhaps these commands should be preceded by
1332 *	CHECK POWER MODE to see what power mode the device is already in.
1333 *	[See SAT revision 5 at www.t10.org]
1334 *
1335 *	LOCKING:
1336 *	spin_lock_irqsave(host lock)
1337 *
1338 *	RETURNS:
1339 *	Zero on success, non-zero on error.
1340 */
1341static unsigned int ata_scsi_start_stop_xlat(struct ata_queued_cmd *qc)
1342{
1343	struct scsi_cmnd *scmd = qc->scsicmd;
1344	struct ata_taskfile *tf = &qc->tf;
1345	const u8 *cdb = scmd->cmnd;
1346
1347	if (scmd->cmd_len < 5)
1348		goto invalid_fld;
1349
1350	tf->flags |= ATA_TFLAG_DEVICE | ATA_TFLAG_ISADDR;
1351	tf->protocol = ATA_PROT_NODATA;
1352	if (cdb[1] & 0x1) {
1353		;	/* ignore IMMED bit, violates sat-r05 */
1354	}
1355	if (cdb[4] & 0x2)
1356		goto invalid_fld;       /* LOEJ bit set not supported */
1357	if (((cdb[4] >> 4) & 0xf) != 0)
1358		goto invalid_fld;       /* power conditions not supported */
1359
1360	if (cdb[4] & 0x1) {
1361		tf->nsect = 1;	/* 1 sector, lba=0 */
1362
1363		if (qc->dev->flags & ATA_DFLAG_LBA) {
1364			tf->flags |= ATA_TFLAG_LBA;
1365
1366			tf->lbah = 0x0;
1367			tf->lbam = 0x0;
1368			tf->lbal = 0x0;
1369			tf->device |= ATA_LBA;
1370		} else {
1371			/* CHS */
1372			tf->lbal = 0x1; /* sect */
1373			tf->lbam = 0x0; /* cyl low */
1374			tf->lbah = 0x0; /* cyl high */
1375		}
1376
1377		tf->command = ATA_CMD_VERIFY;	/* READ VERIFY */
1378	} else {
1379		/* Some odd clown BIOSen issue spindown on power off (ACPI S4
1380		 * or S5) causing some drives to spin up and down again.
1381		 */
1382		if ((qc->ap->flags & ATA_FLAG_NO_POWEROFF_SPINDOWN) &&
1383		    system_state == SYSTEM_POWER_OFF)
1384			goto skip;
1385
1386		if ((qc->ap->flags & ATA_FLAG_NO_HIBERNATE_SPINDOWN) &&
1387		     system_entering_hibernation())
1388			goto skip;
1389
1390		/* Issue ATA STANDBY IMMEDIATE command */
1391		tf->command = ATA_CMD_STANDBYNOW1;
1392	}
1393
1394	/*
1395	 * Standby and Idle condition timers could be implemented but that
1396	 * would require libata to implement the Power condition mode page
1397	 * and allow the user to change it. Changing mode pages requires
1398	 * MODE SELECT to be implemented.
1399	 */
1400
1401	return 0;
1402
1403 invalid_fld:
1404	ata_scsi_set_sense(scmd, ILLEGAL_REQUEST, 0x24, 0x0);
1405	/* "Invalid field in cbd" */
1406	return 1;
1407 skip:
1408	scmd->result = SAM_STAT_GOOD;
1409	return 1;
1410}
1411
1412
1413/**
1414 *	ata_scsi_flush_xlat - Translate SCSI SYNCHRONIZE CACHE command
1415 *	@qc: Storage for translated ATA taskfile
1416 *
1417 *	Sets up an ATA taskfile to issue FLUSH CACHE or
1418 *	FLUSH CACHE EXT.
1419 *
1420 *	LOCKING:
1421 *	spin_lock_irqsave(host lock)
1422 *
1423 *	RETURNS:
1424 *	Zero on success, non-zero on error.
1425 */
1426static unsigned int ata_scsi_flush_xlat(struct ata_queued_cmd *qc)
1427{
1428	struct ata_taskfile *tf = &qc->tf;
1429
1430	tf->flags |= ATA_TFLAG_DEVICE;
1431	tf->protocol = ATA_PROT_NODATA;
1432
1433	if (qc->dev->flags & ATA_DFLAG_FLUSH_EXT)
1434		tf->command = ATA_CMD_FLUSH_EXT;
1435	else
1436		tf->command = ATA_CMD_FLUSH;
1437
1438	/* flush is critical for IO integrity, consider it an IO command */
1439	qc->flags |= ATA_QCFLAG_IO;
1440
1441	return 0;
1442}
1443
1444/**
1445 *	scsi_6_lba_len - Get LBA and transfer length
1446 *	@cdb: SCSI command to translate
1447 *
1448 *	Calculate LBA and transfer length for 6-byte commands.
1449 *
1450 *	RETURNS:
1451 *	@plba: the LBA
1452 *	@plen: the transfer length
1453 */
1454static void scsi_6_lba_len(const u8 *cdb, u64 *plba, u32 *plen)
1455{
1456	u64 lba = 0;
1457	u32 len;
1458
1459	VPRINTK("six-byte command\n");
1460
1461	lba |= ((u64)(cdb[1] & 0x1f)) << 16;
1462	lba |= ((u64)cdb[2]) << 8;
1463	lba |= ((u64)cdb[3]);
1464
1465	len = cdb[4];
1466
1467	*plba = lba;
1468	*plen = len;
1469}
1470
1471/**
1472 *	scsi_10_lba_len - Get LBA and transfer length
1473 *	@cdb: SCSI command to translate
1474 *
1475 *	Calculate LBA and transfer length for 10-byte commands.
1476 *
1477 *	RETURNS:
1478 *	@plba: the LBA
1479 *	@plen: the transfer length
1480 */
1481static void scsi_10_lba_len(const u8 *cdb, u64 *plba, u32 *plen)
1482{
1483	u64 lba = 0;
1484	u32 len = 0;
1485
1486	VPRINTK("ten-byte command\n");
1487
1488	lba |= ((u64)cdb[2]) << 24;
1489	lba |= ((u64)cdb[3]) << 16;
1490	lba |= ((u64)cdb[4]) << 8;
1491	lba |= ((u64)cdb[5]);
1492
1493	len |= ((u32)cdb[7]) << 8;
1494	len |= ((u32)cdb[8]);
1495
1496	*plba = lba;
1497	*plen = len;
1498}
1499
1500/**
1501 *	scsi_16_lba_len - Get LBA and transfer length
1502 *	@cdb: SCSI command to translate
1503 *
1504 *	Calculate LBA and transfer length for 16-byte commands.
1505 *
1506 *	RETURNS:
1507 *	@plba: the LBA
1508 *	@plen: the transfer length
1509 */
1510static void scsi_16_lba_len(const u8 *cdb, u64 *plba, u32 *plen)
1511{
1512	u64 lba = 0;
1513	u32 len = 0;
1514
1515	VPRINTK("sixteen-byte command\n");
1516
1517	lba |= ((u64)cdb[2]) << 56;
1518	lba |= ((u64)cdb[3]) << 48;
1519	lba |= ((u64)cdb[4]) << 40;
1520	lba |= ((u64)cdb[5]) << 32;
1521	lba |= ((u64)cdb[6]) << 24;
1522	lba |= ((u64)cdb[7]) << 16;
1523	lba |= ((u64)cdb[8]) << 8;
1524	lba |= ((u64)cdb[9]);
1525
1526	len |= ((u32)cdb[10]) << 24;
1527	len |= ((u32)cdb[11]) << 16;
1528	len |= ((u32)cdb[12]) << 8;
1529	len |= ((u32)cdb[13]);
1530
1531	*plba = lba;
1532	*plen = len;
1533}
1534
1535/**
1536 *	ata_scsi_verify_xlat - Translate SCSI VERIFY command into an ATA one
1537 *	@qc: Storage for translated ATA taskfile
1538 *
1539 *	Converts SCSI VERIFY command to an ATA READ VERIFY command.
1540 *
1541 *	LOCKING:
1542 *	spin_lock_irqsave(host lock)
1543 *
1544 *	RETURNS:
1545 *	Zero on success, non-zero on error.
1546 */
1547static unsigned int ata_scsi_verify_xlat(struct ata_queued_cmd *qc)
1548{
1549	struct scsi_cmnd *scmd = qc->scsicmd;
1550	struct ata_taskfile *tf = &qc->tf;
1551	struct ata_device *dev = qc->dev;
1552	u64 dev_sectors = qc->dev->n_sectors;
1553	const u8 *cdb = scmd->cmnd;
1554	u64 block;
1555	u32 n_block;
1556
1557	tf->flags |= ATA_TFLAG_ISADDR | ATA_TFLAG_DEVICE;
1558	tf->protocol = ATA_PROT_NODATA;
1559
1560	if (cdb[0] == VERIFY) {
1561		if (scmd->cmd_len < 10)
1562			goto invalid_fld;
1563		scsi_10_lba_len(cdb, &block, &n_block);
1564	} else if (cdb[0] == VERIFY_16) {
1565		if (scmd->cmd_len < 16)
1566			goto invalid_fld;
1567		scsi_16_lba_len(cdb, &block, &n_block);
1568	} else
1569		goto invalid_fld;
1570
1571	if (!n_block)
1572		goto nothing_to_do;
1573	if (block >= dev_sectors)
1574		goto out_of_range;
1575	if ((block + n_block) > dev_sectors)
1576		goto out_of_range;
1577
1578	if (dev->flags & ATA_DFLAG_LBA) {
1579		tf->flags |= ATA_TFLAG_LBA;
1580
1581		if (lba_28_ok(block, n_block)) {
1582			/* use LBA28 */
1583			tf->command = ATA_CMD_VERIFY;
1584			tf->device |= (block >> 24) & 0xf;
1585		} else if (lba_48_ok(block, n_block)) {
1586			if (!(dev->flags & ATA_DFLAG_LBA48))
1587				goto out_of_range;
1588
1589			/* use LBA48 */
1590			tf->flags |= ATA_TFLAG_LBA48;
1591			tf->command = ATA_CMD_VERIFY_EXT;
1592
1593			tf->hob_nsect = (n_block >> 8) & 0xff;
1594
1595			tf->hob_lbah = (block >> 40) & 0xff;
1596			tf->hob_lbam = (block >> 32) & 0xff;
1597			tf->hob_lbal = (block >> 24) & 0xff;
1598		} else
1599			/* request too large even for LBA48 */
1600			goto out_of_range;
1601
1602		tf->nsect = n_block & 0xff;
1603
1604		tf->lbah = (block >> 16) & 0xff;
1605		tf->lbam = (block >> 8) & 0xff;
1606		tf->lbal = block & 0xff;
1607
1608		tf->device |= ATA_LBA;
1609	} else {
1610		/* CHS */
1611		u32 sect, head, cyl, track;
1612
1613		if (!lba_28_ok(block, n_block))
1614			goto out_of_range;
1615
1616		/* Convert LBA to CHS */
1617		track = (u32)block / dev->sectors;
1618		cyl   = track / dev->heads;
1619		head  = track % dev->heads;
1620		sect  = (u32)block % dev->sectors + 1;
1621
1622		DPRINTK("block %u track %u cyl %u head %u sect %u\n",
1623			(u32)block, track, cyl, head, sect);
1624
1625		/* Check whether the converted CHS can fit.
1626		   Cylinder: 0-65535
1627		   Head: 0-15
1628		   Sector: 1-255*/
1629		if ((cyl >> 16) || (head >> 4) || (sect >> 8) || (!sect))
1630			goto out_of_range;
1631
1632		tf->command = ATA_CMD_VERIFY;
1633		tf->nsect = n_block & 0xff; /* Sector count 0 means 256 sectors */
1634		tf->lbal = sect;
1635		tf->lbam = cyl;
1636		tf->lbah = cyl >> 8;
1637		tf->device |= head;
1638	}
1639
1640	return 0;
1641
1642invalid_fld:
1643	ata_scsi_set_sense(scmd, ILLEGAL_REQUEST, 0x24, 0x0);
1644	/* "Invalid field in cbd" */
1645	return 1;
1646
1647out_of_range:
1648	ata_scsi_set_sense(scmd, ILLEGAL_REQUEST, 0x21, 0x0);
1649	/* "Logical Block Address out of range" */
1650	return 1;
1651
1652nothing_to_do:
1653	scmd->result = SAM_STAT_GOOD;
1654	return 1;
1655}
1656
1657/**
1658 *	ata_scsi_rw_xlat - Translate SCSI r/w command into an ATA one
1659 *	@qc: Storage for translated ATA taskfile
1660 *
1661 *	Converts any of six SCSI read/write commands into the
1662 *	ATA counterpart, including starting sector (LBA),
1663 *	sector count, and taking into account the device's LBA48
1664 *	support.
1665 *
1666 *	Commands %READ_6, %READ_10, %READ_16, %WRITE_6, %WRITE_10, and
1667 *	%WRITE_16 are currently supported.
1668 *
1669 *	LOCKING:
1670 *	spin_lock_irqsave(host lock)
1671 *
1672 *	RETURNS:
1673 *	Zero on success, non-zero on error.
1674 */
1675static unsigned int ata_scsi_rw_xlat(struct ata_queued_cmd *qc)
1676{
1677	struct scsi_cmnd *scmd = qc->scsicmd;
1678	const u8 *cdb = scmd->cmnd;
1679	unsigned int tf_flags = 0;
1680	u64 block;
1681	u32 n_block;
1682	int rc;
1683
1684	if (cdb[0] == WRITE_10 || cdb[0] == WRITE_6 || cdb[0] == WRITE_16)
1685		tf_flags |= ATA_TFLAG_WRITE;
1686
1687	/* Calculate the SCSI LBA, transfer length and FUA. */
1688	switch (cdb[0]) {
1689	case READ_10:
1690	case WRITE_10:
1691		if (unlikely(scmd->cmd_len < 10))
1692			goto invalid_fld;
1693		scsi_10_lba_len(cdb, &block, &n_block);
1694		if (cdb[1] & (1 << 3))
1695			tf_flags |= ATA_TFLAG_FUA;
1696		break;
1697	case READ_6:
1698	case WRITE_6:
1699		if (unlikely(scmd->cmd_len < 6))
1700			goto invalid_fld;
1701		scsi_6_lba_len(cdb, &block, &n_block);
1702
1703		/* for 6-byte r/w commands, transfer length 0
1704		 * means 256 blocks of data, not 0 block.
1705		 */
1706		if (!n_block)
1707			n_block = 256;
1708		break;
1709	case READ_16:
1710	case WRITE_16:
1711		if (unlikely(scmd->cmd_len < 16))
1712			goto invalid_fld;
1713		scsi_16_lba_len(cdb, &block, &n_block);
1714		if (cdb[1] & (1 << 3))
1715			tf_flags |= ATA_TFLAG_FUA;
1716		break;
1717	default:
1718		DPRINTK("no-byte command\n");
1719		goto invalid_fld;
1720	}
1721
1722	/* Check and compose ATA command */
1723	if (!n_block)
1724		/* For 10-byte and 16-byte SCSI R/W commands, transfer
1725		 * length 0 means transfer 0 block of data.
1726		 * However, for ATA R/W commands, sector count 0 means
1727		 * 256 or 65536 sectors, not 0 sectors as in SCSI.
1728		 *
1729		 * WARNING: one or two older ATA drives treat 0 as 0...
1730		 */
1731		goto nothing_to_do;
1732
1733	qc->flags |= ATA_QCFLAG_IO;
1734	qc->nbytes = n_block * scmd->device->sector_size;
1735
1736	rc = ata_build_rw_tf(&qc->tf, qc->dev, block, n_block, tf_flags,
1737			     qc->tag);
1738	if (likely(rc == 0))
1739		return 0;
1740
1741	if (rc == -ERANGE)
1742		goto out_of_range;
1743	/* treat all other errors as -EINVAL, fall through */
1744invalid_fld:
1745	ata_scsi_set_sense(scmd, ILLEGAL_REQUEST, 0x24, 0x0);
1746	/* "Invalid field in cbd" */
1747	return 1;
1748
1749out_of_range:
1750	ata_scsi_set_sense(scmd, ILLEGAL_REQUEST, 0x21, 0x0);
1751	/* "Logical Block Address out of range" */
1752	return 1;
1753
1754nothing_to_do:
1755	scmd->result = SAM_STAT_GOOD;
1756	return 1;
1757}
1758
1759static void ata_scsi_qc_complete(struct ata_queued_cmd *qc)
1760{
1761	struct ata_port *ap = qc->ap;
1762	struct scsi_cmnd *cmd = qc->scsicmd;
1763	u8 *cdb = cmd->cmnd;
1764	int need_sense = (qc->err_mask != 0);
1765
1766	/* For ATA pass thru (SAT) commands, generate a sense block if
1767	 * user mandated it or if there's an error.  Note that if we
1768	 * generate because the user forced us to [CK_COND =1], a check
1769	 * condition is generated and the ATA register values are returned
1770	 * whether the command completed successfully or not. If there
1771	 * was no error, we use the following sense data:
1772	 * sk = RECOVERED ERROR
1773	 * asc,ascq = ATA PASS-THROUGH INFORMATION AVAILABLE
1774	 */
1775	if (((cdb[0] == ATA_16) || (cdb[0] == ATA_12)) &&
1776	    ((cdb[2] & 0x20) || need_sense)) {
1777		ata_gen_passthru_sense(qc);
1778	} else {
1779		if (!need_sense) {
1780			cmd->result = SAM_STAT_GOOD;
1781		} else {
1782			/* TODO: decide which descriptor format to use
1783			 * for 48b LBA devices and call that here
1784			 * instead of the fixed desc, which is only
1785			 * good for smaller LBA (and maybe CHS?)
1786			 * devices.
1787			 */
1788			ata_gen_ata_sense(qc);
1789		}
1790	}
1791
1792	if (need_sense && !ap->ops->error_handler)
1793		ata_dump_status(ap->print_id, &qc->result_tf);
1794
1795	qc->scsidone(cmd);
1796
1797	ata_qc_free(qc);
1798}
1799
1800/**
1801 *	ata_scsi_translate - Translate then issue SCSI command to ATA device
1802 *	@dev: ATA device to which the command is addressed
1803 *	@cmd: SCSI command to execute
1804 *	@xlat_func: Actor which translates @cmd to an ATA taskfile
1805 *
1806 *	Our ->queuecommand() function has decided that the SCSI
1807 *	command issued can be directly translated into an ATA
1808 *	command, rather than handled internally.
1809 *
1810 *	This function sets up an ata_queued_cmd structure for the
1811 *	SCSI command, and sends that ata_queued_cmd to the hardware.
1812 *
1813 *	The xlat_func argument (actor) returns 0 if ready to execute
1814 *	ATA command, else 1 to finish translation. If 1 is returned
1815 *	then cmd->result (and possibly cmd->sense_buffer) are assumed
1816 *	to be set reflecting an error condition or clean (early)
1817 *	termination.
1818 *
1819 *	LOCKING:
1820 *	spin_lock_irqsave(host lock)
1821 *
1822 *	RETURNS:
1823 *	0 on success, SCSI_ML_QUEUE_DEVICE_BUSY if the command
1824 *	needs to be deferred.
1825 */
1826static int ata_scsi_translate(struct ata_device *dev, struct scsi_cmnd *cmd,
1827			      ata_xlat_func_t xlat_func)
1828{
1829	struct ata_port *ap = dev->link->ap;
1830	struct ata_queued_cmd *qc;
1831	int rc;
1832
1833	VPRINTK("ENTER\n");
1834
1835	qc = ata_scsi_qc_new(dev, cmd);
1836	if (!qc)
1837		goto err_mem;
1838
1839	/* data is present; dma-map it */
1840	if (cmd->sc_data_direction == DMA_FROM_DEVICE ||
1841	    cmd->sc_data_direction == DMA_TO_DEVICE) {
1842		if (unlikely(scsi_bufflen(cmd) < 1)) {
1843			ata_dev_warn(dev, "WARNING: zero len r/w req\n");
1844			goto err_did;
1845		}
1846
1847		ata_sg_init(qc, scsi_sglist(cmd), scsi_sg_count(cmd));
1848
1849		qc->dma_dir = cmd->sc_data_direction;
1850	}
1851
1852	qc->complete_fn = ata_scsi_qc_complete;
1853
1854	if (xlat_func(qc))
1855		goto early_finish;
1856
1857	if (ap->ops->qc_defer) {
1858		if ((rc = ap->ops->qc_defer(qc)))
1859			goto defer;
1860	}
1861
1862	/* select device, send command to hardware */
1863	ata_qc_issue(qc);
1864
1865	VPRINTK("EXIT\n");
1866	return 0;
1867
1868early_finish:
1869	ata_qc_free(qc);
1870	cmd->scsi_done(cmd);
1871	DPRINTK("EXIT - early finish (good or error)\n");
1872	return 0;
1873
1874err_did:
1875	ata_qc_free(qc);
1876	cmd->result = (DID_ERROR << 16);
1877	cmd->scsi_done(cmd);
1878err_mem:
1879	DPRINTK("EXIT - internal\n");
1880	return 0;
1881
1882defer:
1883	ata_qc_free(qc);
1884	DPRINTK("EXIT - defer\n");
1885	if (rc == ATA_DEFER_LINK)
1886		return SCSI_MLQUEUE_DEVICE_BUSY;
1887	else
1888		return SCSI_MLQUEUE_HOST_BUSY;
1889}
1890
1891/**
1892 *	ata_scsi_rbuf_get - Map response buffer.
1893 *	@cmd: SCSI command containing buffer to be mapped.
1894 *	@flags: unsigned long variable to store irq enable status
1895 *	@copy_in: copy in from user buffer
1896 *
1897 *	Prepare buffer for simulated SCSI commands.
1898 *
1899 *	LOCKING:
1900 *	spin_lock_irqsave(ata_scsi_rbuf_lock) on success
1901 *
1902 *	RETURNS:
1903 *	Pointer to response buffer.
1904 */
1905static void *ata_scsi_rbuf_get(struct scsi_cmnd *cmd, bool copy_in,
1906			       unsigned long *flags)
1907{
1908	spin_lock_irqsave(&ata_scsi_rbuf_lock, *flags);
1909
1910	memset(ata_scsi_rbuf, 0, ATA_SCSI_RBUF_SIZE);
1911	if (copy_in)
1912		sg_copy_to_buffer(scsi_sglist(cmd), scsi_sg_count(cmd),
1913				  ata_scsi_rbuf, ATA_SCSI_RBUF_SIZE);
1914	return ata_scsi_rbuf;
1915}
1916
1917/**
1918 *	ata_scsi_rbuf_put - Unmap response buffer.
1919 *	@cmd: SCSI command containing buffer to be unmapped.
1920 *	@copy_out: copy out result
1921 *	@flags: @flags passed to ata_scsi_rbuf_get()
1922 *
1923 *	Returns rbuf buffer.  The result is copied to @cmd's buffer if
1924 *	@copy_back is true.
1925 *
1926 *	LOCKING:
1927 *	Unlocks ata_scsi_rbuf_lock.
1928 */
1929static inline void ata_scsi_rbuf_put(struct scsi_cmnd *cmd, bool copy_out,
1930				     unsigned long *flags)
1931{
1932	if (copy_out)
1933		sg_copy_from_buffer(scsi_sglist(cmd), scsi_sg_count(cmd),
1934				    ata_scsi_rbuf, ATA_SCSI_RBUF_SIZE);
1935	spin_unlock_irqrestore(&ata_scsi_rbuf_lock, *flags);
1936}
1937
1938/**
1939 *	ata_scsi_rbuf_fill - wrapper for SCSI command simulators
1940 *	@args: device IDENTIFY data / SCSI command of interest.
1941 *	@actor: Callback hook for desired SCSI command simulator
1942 *
1943 *	Takes care of the hard work of simulating a SCSI command...
1944 *	Mapping the response buffer, calling the command's handler,
1945 *	and handling the handler's return value.  This return value
1946 *	indicates whether the handler wishes the SCSI command to be
1947 *	completed successfully (0), or not (in which case cmd->result
1948 *	and sense buffer are assumed to be set).
1949 *
1950 *	LOCKING:
1951 *	spin_lock_irqsave(host lock)
1952 */
1953static void ata_scsi_rbuf_fill(struct ata_scsi_args *args,
1954		unsigned int (*actor)(struct ata_scsi_args *args, u8 *rbuf))
1955{
1956	u8 *rbuf;
1957	unsigned int rc;
1958	struct scsi_cmnd *cmd = args->cmd;
1959	unsigned long flags;
1960
1961	rbuf = ata_scsi_rbuf_get(cmd, false, &flags);
1962	rc = actor(args, rbuf);
1963	ata_scsi_rbuf_put(cmd, rc == 0, &flags);
1964
1965	if (rc == 0)
1966		cmd->result = SAM_STAT_GOOD;
1967	args->done(cmd);
1968}
1969
1970/**
1971 *	ata_scsiop_inq_std - Simulate INQUIRY command
1972 *	@args: device IDENTIFY data / SCSI command of interest.
1973 *	@rbuf: Response buffer, to which simulated SCSI cmd output is sent.
1974 *
1975 *	Returns standard device identification data associated
1976 *	with non-VPD INQUIRY command output.
1977 *
1978 *	LOCKING:
1979 *	spin_lock_irqsave(host lock)
1980 */
1981static unsigned int ata_scsiop_inq_std(struct ata_scsi_args *args, u8 *rbuf)
1982{
1983	const u8 versions[] = {
1984		0x00,
1985		0x60,	/* SAM-3 (no version claimed) */
1986
1987		0x03,
1988		0x20,	/* SBC-2 (no version claimed) */
1989
1990		0x02,
1991		0x60	/* SPC-3 (no version claimed) */
1992	};
1993	const u8 versions_zbc[] = {
1994		0x00,
1995		0xA0,	/* SAM-5 (no version claimed) */
1996
1997		0x04,
1998		0xC0,	/* SBC-3 (no version claimed) */
1999
2000		0x04,
2001		0x60,	/* SPC-4 (no version claimed) */
2002
2003		0x60,
2004		0x20,   /* ZBC (no version claimed) */
2005	};
2006
2007	u8 hdr[] = {
2008		TYPE_DISK,
2009		0,
2010		0x5,	/* claim SPC-3 version compatibility */
2011		2,
2012		95 - 4
2013	};
2014
2015	VPRINTK("ENTER\n");
2016
2017	/* set scsi removable (RMB) bit per ata bit */
2018	if (ata_id_removable(args->id))
2019		hdr[1] |= (1 << 7);
2020
2021	if (args->dev->class == ATA_DEV_ZAC) {
2022		hdr[0] = TYPE_ZBC;
2023		hdr[2] = 0x6; /* ZBC is defined in SPC-4 */
2024	}
2025
2026	memcpy(rbuf, hdr, sizeof(hdr));
2027	memcpy(&rbuf[8], "ATA     ", 8);
2028	ata_id_string(args->id, &rbuf[16], ATA_ID_PROD, 16);
2029
2030	/* From SAT, use last 2 words from fw rev unless they are spaces */
2031	ata_id_string(args->id, &rbuf[32], ATA_ID_FW_REV + 2, 4);
2032	if (strncmp(&rbuf[32], "    ", 4) == 0)
2033		ata_id_string(args->id, &rbuf[32], ATA_ID_FW_REV, 4);
2034
2035	if (rbuf[32] == 0 || rbuf[32] == ' ')
2036		memcpy(&rbuf[32], "n/a ", 4);
2037
2038	if (args->dev->class == ATA_DEV_ZAC)
2039		memcpy(rbuf + 58, versions_zbc, sizeof(versions_zbc));
2040	else
2041		memcpy(rbuf + 58, versions, sizeof(versions));
2042
2043	return 0;
2044}
2045
2046/**
2047 *	ata_scsiop_inq_00 - Simulate INQUIRY VPD page 0, list of pages
2048 *	@args: device IDENTIFY data / SCSI command of interest.
2049 *	@rbuf: Response buffer, to which simulated SCSI cmd output is sent.
2050 *
2051 *	Returns list of inquiry VPD pages available.
2052 *
2053 *	LOCKING:
2054 *	spin_lock_irqsave(host lock)
2055 */
2056static unsigned int ata_scsiop_inq_00(struct ata_scsi_args *args, u8 *rbuf)
2057{
2058	const u8 pages[] = {
2059		0x00,	/* page 0x00, this page */
2060		0x80,	/* page 0x80, unit serial no page */
2061		0x83,	/* page 0x83, device ident page */
2062		0x89,	/* page 0x89, ata info page */
2063		0xb0,	/* page 0xb0, block limits page */
2064		0xb1,	/* page 0xb1, block device characteristics page */
2065		0xb2,	/* page 0xb2, thin provisioning page */
2066	};
2067
2068	rbuf[3] = sizeof(pages);	/* number of supported VPD pages */
2069	memcpy(rbuf + 4, pages, sizeof(pages));
2070	return 0;
2071}
2072
2073/**
2074 *	ata_scsiop_inq_80 - Simulate INQUIRY VPD page 80, device serial number
2075 *	@args: device IDENTIFY data / SCSI command of interest.
2076 *	@rbuf: Response buffer, to which simulated SCSI cmd output is sent.
2077 *
2078 *	Returns ATA device serial number.
2079 *
2080 *	LOCKING:
2081 *	spin_lock_irqsave(host lock)
2082 */
2083static unsigned int ata_scsiop_inq_80(struct ata_scsi_args *args, u8 *rbuf)
2084{
2085	const u8 hdr[] = {
2086		0,
2087		0x80,			/* this page code */
2088		0,
2089		ATA_ID_SERNO_LEN,	/* page len */
2090	};
2091
2092	memcpy(rbuf, hdr, sizeof(hdr));
2093	ata_id_string(args->id, (unsigned char *) &rbuf[4],
2094		      ATA_ID_SERNO, ATA_ID_SERNO_LEN);
2095	return 0;
2096}
2097
2098/**
2099 *	ata_scsiop_inq_83 - Simulate INQUIRY VPD page 83, device identity
2100 *	@args: device IDENTIFY data / SCSI command of interest.
2101 *	@rbuf: Response buffer, to which simulated SCSI cmd output is sent.
2102 *
2103 *	Yields two logical unit device identification designators:
2104 *	 - vendor specific ASCII containing the ATA serial number
2105 *	 - SAT defined "t10 vendor id based" containing ASCII vendor
2106 *	   name ("ATA     "), model and serial numbers.
2107 *
2108 *	LOCKING:
2109 *	spin_lock_irqsave(host lock)
2110 */
2111static unsigned int ata_scsiop_inq_83(struct ata_scsi_args *args, u8 *rbuf)
2112{
2113	const int sat_model_serial_desc_len = 68;
2114	int num;
2115
2116	rbuf[1] = 0x83;			/* this page code */
2117	num = 4;
2118
2119	/* piv=0, assoc=lu, code_set=ACSII, designator=vendor */
2120	rbuf[num + 0] = 2;
2121	rbuf[num + 3] = ATA_ID_SERNO_LEN;
2122	num += 4;
2123	ata_id_string(args->id, (unsigned char *) rbuf + num,
2124		      ATA_ID_SERNO, ATA_ID_SERNO_LEN);
2125	num += ATA_ID_SERNO_LEN;
2126
2127	/* SAT defined lu model and serial numbers descriptor */
2128	/* piv=0, assoc=lu, code_set=ACSII, designator=t10 vendor id */
2129	rbuf[num + 0] = 2;
2130	rbuf[num + 1] = 1;
2131	rbuf[num + 3] = sat_model_serial_desc_len;
2132	num += 4;
2133	memcpy(rbuf + num, "ATA     ", 8);
2134	num += 8;
2135	ata_id_string(args->id, (unsigned char *) rbuf + num, ATA_ID_PROD,
2136		      ATA_ID_PROD_LEN);
2137	num += ATA_ID_PROD_LEN;
2138	ata_id_string(args->id, (unsigned char *) rbuf + num, ATA_ID_SERNO,
2139		      ATA_ID_SERNO_LEN);
2140	num += ATA_ID_SERNO_LEN;
2141
2142	if (ata_id_has_wwn(args->id)) {
2143		/* SAT defined lu world wide name */
2144		/* piv=0, assoc=lu, code_set=binary, designator=NAA */
2145		rbuf[num + 0] = 1;
2146		rbuf[num + 1] = 3;
2147		rbuf[num + 3] = ATA_ID_WWN_LEN;
2148		num += 4;
2149		ata_id_string(args->id, (unsigned char *) rbuf + num,
2150			      ATA_ID_WWN, ATA_ID_WWN_LEN);
2151		num += ATA_ID_WWN_LEN;
2152	}
2153	rbuf[3] = num - 4;    /* page len (assume less than 256 bytes) */
2154	return 0;
2155}
2156
2157/**
2158 *	ata_scsiop_inq_89 - Simulate INQUIRY VPD page 89, ATA info
2159 *	@args: device IDENTIFY data / SCSI command of interest.
2160 *	@rbuf: Response buffer, to which simulated SCSI cmd output is sent.
2161 *
2162 *	Yields SAT-specified ATA VPD page.
2163 *
2164 *	LOCKING:
2165 *	spin_lock_irqsave(host lock)
2166 */
2167static unsigned int ata_scsiop_inq_89(struct ata_scsi_args *args, u8 *rbuf)
2168{
2169	struct ata_taskfile tf;
2170
2171	memset(&tf, 0, sizeof(tf));
2172
2173	rbuf[1] = 0x89;			/* our page code */
2174	rbuf[2] = (0x238 >> 8);		/* page size fixed at 238h */
2175	rbuf[3] = (0x238 & 0xff);
2176
2177	memcpy(&rbuf[8], "linux   ", 8);
2178	memcpy(&rbuf[16], "libata          ", 16);
2179	memcpy(&rbuf[32], DRV_VERSION, 4);
2180
2181	/* we don't store the ATA device signature, so we fake it */
2182
2183	tf.command = ATA_DRDY;		/* really, this is Status reg */
2184	tf.lbal = 0x1;
2185	tf.nsect = 0x1;
2186
2187	ata_tf_to_fis(&tf, 0, 1, &rbuf[36]);	/* TODO: PMP? */
2188	rbuf[36] = 0x34;		/* force D2H Reg FIS (34h) */
2189
2190	rbuf[56] = ATA_CMD_ID_ATA;
2191
2192	memcpy(&rbuf[60], &args->id[0], 512);
2193	return 0;
2194}
2195
2196static unsigned int ata_scsiop_inq_b0(struct ata_scsi_args *args, u8 *rbuf)
2197{
2198	u16 min_io_sectors;
2199
2200	rbuf[1] = 0xb0;
2201	rbuf[3] = 0x3c;		/* required VPD size with unmap support */
2202
2203	/*
2204	 * Optimal transfer length granularity.
2205	 *
2206	 * This is always one physical block, but for disks with a smaller
2207	 * logical than physical sector size we need to figure out what the
2208	 * latter is.
2209	 */
2210	min_io_sectors = 1 << ata_id_log2_per_physical_sector(args->id);
2211	put_unaligned_be16(min_io_sectors, &rbuf[6]);
2212
2213	/*
2214	 * Optimal unmap granularity.
2215	 *
2216	 * The ATA spec doesn't even know about a granularity or alignment
2217	 * for the TRIM command.  We can leave away most of the unmap related
2218	 * VPD page entries, but we have specifify a granularity to signal
2219	 * that we support some form of unmap - in thise case via WRITE SAME
2220	 * with the unmap bit set.
2221	 */
2222	if (ata_id_has_trim(args->id)) {
2223		put_unaligned_be64(65535 * 512 / 8, &rbuf[36]);
2224		put_unaligned_be32(1, &rbuf[28]);
2225	}
2226
2227	return 0;
2228}
2229
2230static unsigned int ata_scsiop_inq_b1(struct ata_scsi_args *args, u8 *rbuf)
2231{
2232	int form_factor = ata_id_form_factor(args->id);
2233	int media_rotation_rate = ata_id_rotation_rate(args->id);
2234
2235	rbuf[1] = 0xb1;
2236	rbuf[3] = 0x3c;
2237	rbuf[4] = media_rotation_rate >> 8;
2238	rbuf[5] = media_rotation_rate;
2239	rbuf[7] = form_factor;
2240
2241	return 0;
2242}
2243
2244static unsigned int ata_scsiop_inq_b2(struct ata_scsi_args *args, u8 *rbuf)
2245{
2246	/* SCSI Thin Provisioning VPD page: SBC-3 rev 22 or later */
2247	rbuf[1] = 0xb2;
2248	rbuf[3] = 0x4;
2249	rbuf[5] = 1 << 6;	/* TPWS */
2250
2251	return 0;
2252}
2253
2254/**
2255 *	ata_scsiop_noop - Command handler that simply returns success.
2256 *	@args: device IDENTIFY data / SCSI command of interest.
2257 *	@rbuf: Response buffer, to which simulated SCSI cmd output is sent.
2258 *
2259 *	No operation.  Simply returns success to caller, to indicate
2260 *	that the caller should successfully complete this SCSI command.
2261 *
2262 *	LOCKING:
2263 *	spin_lock_irqsave(host lock)
2264 */
2265static unsigned int ata_scsiop_noop(struct ata_scsi_args *args, u8 *rbuf)
2266{
2267	VPRINTK("ENTER\n");
2268	return 0;
2269}
2270
2271/**
2272 *	modecpy - Prepare response for MODE SENSE
2273 *	@dest: output buffer
2274 *	@src: data being copied
2275 *	@n: length of mode page
2276 *	@changeable: whether changeable parameters are requested
2277 *
2278 *	Generate a generic MODE SENSE page for either current or changeable
2279 *	parameters.
2280 *
2281 *	LOCKING:
2282 *	None.
2283 */
2284static void modecpy(u8 *dest, const u8 *src, int n, bool changeable)
2285{
2286	if (changeable) {
2287		memcpy(dest, src, 2);
2288		memset(dest + 2, 0, n - 2);
2289	} else {
2290		memcpy(dest, src, n);
2291	}
2292}
2293
2294/**
2295 *	ata_msense_caching - Simulate MODE SENSE caching info page
2296 *	@id: device IDENTIFY data
2297 *	@buf: output buffer
2298 *	@changeable: whether changeable parameters are requested
2299 *
2300 *	Generate a caching info page, which conditionally indicates
2301 *	write caching to the SCSI layer, depending on device
2302 *	capabilities.
2303 *
2304 *	LOCKING:
2305 *	None.
2306 */
2307static unsigned int ata_msense_caching(u16 *id, u8 *buf, bool changeable)
2308{
2309	modecpy(buf, def_cache_mpage, sizeof(def_cache_mpage), changeable);
2310	if (changeable || ata_id_wcache_enabled(id))
2311		buf[2] |= (1 << 2);	/* write cache enable */
2312	if (!changeable && !ata_id_rahead_enabled(id))
2313		buf[12] |= (1 << 5);	/* disable read ahead */
2314	return sizeof(def_cache_mpage);
2315}
2316
2317/**
2318 *	ata_msense_ctl_mode - Simulate MODE SENSE control mode page
2319 *	@buf: output buffer
2320 *	@changeable: whether changeable parameters are requested
2321 *
2322 *	Generate a generic MODE SENSE control mode page.
2323 *
2324 *	LOCKING:
2325 *	None.
2326 */
2327static unsigned int ata_msense_ctl_mode(u8 *buf, bool changeable)
2328{
2329	modecpy(buf, def_control_mpage, sizeof(def_control_mpage), changeable);
2330	return sizeof(def_control_mpage);
2331}
2332
2333/**
2334 *	ata_msense_rw_recovery - Simulate MODE SENSE r/w error recovery page
2335 *	@buf: output buffer
2336 *	@changeable: whether changeable parameters are requested
2337 *
2338 *	Generate a generic MODE SENSE r/w error recovery page.
2339 *
2340 *	LOCKING:
2341 *	None.
2342 */
2343static unsigned int ata_msense_rw_recovery(u8 *buf, bool changeable)
2344{
2345	modecpy(buf, def_rw_recovery_mpage, sizeof(def_rw_recovery_mpage),
2346		changeable);
2347	return sizeof(def_rw_recovery_mpage);
2348}
2349
2350/*
2351 * We can turn this into a real blacklist if it's needed, for now just
2352 * blacklist any Maxtor BANC1G10 revision firmware
2353 */
2354static int ata_dev_supports_fua(u16 *id)
2355{
2356	unsigned char model[ATA_ID_PROD_LEN + 1], fw[ATA_ID_FW_REV_LEN + 1];
2357
2358	if (!libata_fua)
2359		return 0;
2360	if (!ata_id_has_fua(id))
2361		return 0;
2362
2363	ata_id_c_string(id, model, ATA_ID_PROD, sizeof(model));
2364	ata_id_c_string(id, fw, ATA_ID_FW_REV, sizeof(fw));
2365
2366	if (strcmp(model, "Maxtor"))
2367		return 1;
2368	if (strcmp(fw, "BANC1G10"))
2369		return 1;
2370
2371	return 0; /* blacklisted */
2372}
2373
2374/**
2375 *	ata_scsiop_mode_sense - Simulate MODE SENSE 6, 10 commands
2376 *	@args: device IDENTIFY data / SCSI command of interest.
2377 *	@rbuf: Response buffer, to which simulated SCSI cmd output is sent.
2378 *
2379 *	Simulate MODE SENSE commands. Assume this is invoked for direct
2380 *	access devices (e.g. disks) only. There should be no block
2381 *	descriptor for other device types.
2382 *
2383 *	LOCKING:
2384 *	spin_lock_irqsave(host lock)
2385 */
2386static unsigned int ata_scsiop_mode_sense(struct ata_scsi_args *args, u8 *rbuf)
2387{
2388	struct ata_device *dev = args->dev;
2389	u8 *scsicmd = args->cmd->cmnd, *p = rbuf;
2390	const u8 sat_blk_desc[] = {
2391		0, 0, 0, 0,	/* number of blocks: sat unspecified */
2392		0,
2393		0, 0x2, 0x0	/* block length: 512 bytes */
2394	};
2395	u8 pg, spg;
2396	unsigned int ebd, page_control, six_byte;
2397	u8 dpofua;
2398
2399	VPRINTK("ENTER\n");
2400
2401	six_byte = (scsicmd[0] == MODE_SENSE);
2402	ebd = !(scsicmd[1] & 0x8);      /* dbd bit inverted == edb */
2403	/*
2404	 * LLBA bit in msense(10) ignored (compliant)
2405	 */
2406
2407	page_control = scsicmd[2] >> 6;
2408	switch (page_control) {
2409	case 0: /* current */
2410	case 1: /* changeable */
2411	case 2: /* defaults */
2412		break;  /* supported */
2413	case 3: /* saved */
2414		goto saving_not_supp;
2415	default:
2416		goto invalid_fld;
2417	}
2418
2419	if (six_byte)
2420		p += 4 + (ebd ? 8 : 0);
2421	else
2422		p += 8 + (ebd ? 8 : 0);
2423
2424	pg = scsicmd[2] & 0x3f;
2425	spg = scsicmd[3];
2426	/*
2427	 * No mode subpages supported (yet) but asking for _all_
2428	 * subpages may be valid
2429	 */
2430	if (spg && (spg != ALL_SUB_MPAGES))
2431		goto invalid_fld;
2432
2433	switch(pg) {
2434	case RW_RECOVERY_MPAGE:
2435		p += ata_msense_rw_recovery(p, page_control == 1);
2436		break;
2437
2438	case CACHE_MPAGE:
2439		p += ata_msense_caching(args->id, p, page_control == 1);
2440		break;
2441
2442	case CONTROL_MPAGE:
2443		p += ata_msense_ctl_mode(p, page_control == 1);
2444		break;
2445
2446	case ALL_MPAGES:
2447		p += ata_msense_rw_recovery(p, page_control == 1);
2448		p += ata_msense_caching(args->id, p, page_control == 1);
2449		p += ata_msense_ctl_mode(p, page_control == 1);
2450		break;
2451
2452	default:		/* invalid page code */
2453		goto invalid_fld;
2454	}
2455
2456	dpofua = 0;
2457	if (ata_dev_supports_fua(args->id) && (dev->flags & ATA_DFLAG_LBA48) &&
2458	    (!(dev->flags & ATA_DFLAG_PIO) || dev->multi_count))
2459		dpofua = 1 << 4;
2460
2461	if (six_byte) {
2462		rbuf[0] = p - rbuf - 1;
2463		rbuf[2] |= dpofua;
2464		if (ebd) {
2465			rbuf[3] = sizeof(sat_blk_desc);
2466			memcpy(rbuf + 4, sat_blk_desc, sizeof(sat_blk_desc));
2467		}
2468	} else {
2469		unsigned int output_len = p - rbuf - 2;
2470
2471		rbuf[0] = output_len >> 8;
2472		rbuf[1] = output_len;
2473		rbuf[3] |= dpofua;
2474		if (ebd) {
2475			rbuf[7] = sizeof(sat_blk_desc);
2476			memcpy(rbuf + 8, sat_blk_desc, sizeof(sat_blk_desc));
2477		}
2478	}
2479	return 0;
2480
2481invalid_fld:
2482	ata_scsi_set_sense(args->cmd, ILLEGAL_REQUEST, 0x24, 0x0);
2483	/* "Invalid field in cbd" */
2484	return 1;
2485
2486saving_not_supp:
2487	ata_scsi_set_sense(args->cmd, ILLEGAL_REQUEST, 0x39, 0x0);
2488	 /* "Saving parameters not supported" */
2489	return 1;
2490}
2491
2492/**
2493 *	ata_scsiop_read_cap - Simulate READ CAPACITY[ 16] commands
2494 *	@args: device IDENTIFY data / SCSI command of interest.
2495 *	@rbuf: Response buffer, to which simulated SCSI cmd output is sent.
2496 *
2497 *	Simulate READ CAPACITY commands.
2498 *
2499 *	LOCKING:
2500 *	None.
2501 */
2502static unsigned int ata_scsiop_read_cap(struct ata_scsi_args *args, u8 *rbuf)
2503{
2504	struct ata_device *dev = args->dev;
2505	u64 last_lba = dev->n_sectors - 1; /* LBA of the last block */
2506	u32 sector_size; /* physical sector size in bytes */
2507	u8 log2_per_phys;
2508	u16 lowest_aligned;
2509
2510	sector_size = ata_id_logical_sector_size(dev->id);
2511	log2_per_phys = ata_id_log2_per_physical_sector(dev->id);
2512	lowest_aligned = ata_id_logical_sector_offset(dev->id, log2_per_phys);
2513
2514	VPRINTK("ENTER\n");
2515
2516	if (args->cmd->cmnd[0] == READ_CAPACITY) {
2517		if (last_lba >= 0xffffffffULL)
2518			last_lba = 0xffffffff;
2519
2520		/* sector count, 32-bit */
2521		rbuf[0] = last_lba >> (8 * 3);
2522		rbuf[1] = last_lba >> (8 * 2);
2523		rbuf[2] = last_lba >> (8 * 1);
2524		rbuf[3] = last_lba;
2525
2526		/* sector size */
2527		rbuf[4] = sector_size >> (8 * 3);
2528		rbuf[5] = sector_size >> (8 * 2);
2529		rbuf[6] = sector_size >> (8 * 1);
2530		rbuf[7] = sector_size;
2531	} else {
2532		/* sector count, 64-bit */
2533		rbuf[0] = last_lba >> (8 * 7);
2534		rbuf[1] = last_lba >> (8 * 6);
2535		rbuf[2] = last_lba >> (8 * 5);
2536		rbuf[3] = last_lba >> (8 * 4);
2537		rbuf[4] = last_lba >> (8 * 3);
2538		rbuf[5] = last_lba >> (8 * 2);
2539		rbuf[6] = last_lba >> (8 * 1);
2540		rbuf[7] = last_lba;
2541
2542		/* sector size */
2543		rbuf[ 8] = sector_size >> (8 * 3);
2544		rbuf[ 9] = sector_size >> (8 * 2);
2545		rbuf[10] = sector_size >> (8 * 1);
2546		rbuf[11] = sector_size;
2547
2548		rbuf[12] = 0;
2549		rbuf[13] = log2_per_phys;
2550		rbuf[14] = (lowest_aligned >> 8) & 0x3f;
2551		rbuf[15] = lowest_aligned;
2552
2553		if (ata_id_has_trim(args->id) &&
2554		    !(dev->horkage & ATA_HORKAGE_NOTRIM)) {
2555			rbuf[14] |= 0x80; /* LBPME */
2556
2557			if (ata_id_has_zero_after_trim(args->id) &&
2558			    dev->horkage & ATA_HORKAGE_ZERO_AFTER_TRIM) {
2559				ata_dev_info(dev, "Enabling discard_zeroes_data\n");
2560				rbuf[14] |= 0x40; /* LBPRZ */
2561			}
2562		}
2563	}
2564	return 0;
2565}
2566
2567/**
2568 *	ata_scsiop_report_luns - Simulate REPORT LUNS command
2569 *	@args: device IDENTIFY data / SCSI command of interest.
2570 *	@rbuf: Response buffer, to which simulated SCSI cmd output is sent.
2571 *
2572 *	Simulate REPORT LUNS command.
2573 *
2574 *	LOCKING:
2575 *	spin_lock_irqsave(host lock)
2576 */
2577static unsigned int ata_scsiop_report_luns(struct ata_scsi_args *args, u8 *rbuf)
2578{
2579	VPRINTK("ENTER\n");
2580	rbuf[3] = 8;	/* just one lun, LUN 0, size 8 bytes */
2581
2582	return 0;
2583}
2584
2585static void atapi_sense_complete(struct ata_queued_cmd *qc)
2586{
2587	if (qc->err_mask && ((qc->err_mask & AC_ERR_DEV) == 0)) {
2588		/* FIXME: not quite right; we don't want the
2589		 * translation of taskfile registers into
2590		 * a sense descriptors, since that's only
2591		 * correct for ATA, not ATAPI
2592		 */
2593		ata_gen_passthru_sense(qc);
2594	}
2595
2596	qc->scsidone(qc->scsicmd);
2597	ata_qc_free(qc);
2598}
2599
2600/* is it pointless to prefer PIO for "safety reasons"? */
2601static inline int ata_pio_use_silly(struct ata_port *ap)
2602{
2603	return (ap->flags & ATA_FLAG_PIO_DMA);
2604}
2605
2606static void atapi_request_sense(struct ata_queued_cmd *qc)
2607{
2608	struct ata_port *ap = qc->ap;
2609	struct scsi_cmnd *cmd = qc->scsicmd;
2610
2611	DPRINTK("ATAPI request sense\n");
2612
2613	memset(cmd->sense_buffer, 0, SCSI_SENSE_BUFFERSIZE);
2614
2615#ifdef CONFIG_ATA_SFF
2616	if (ap->ops->sff_tf_read)
2617		ap->ops->sff_tf_read(ap, &qc->tf);
2618#endif
2619
2620	/* fill these in, for the case where they are -not- overwritten */
2621	cmd->sense_buffer[0] = 0x70;
2622	cmd->sense_buffer[2] = qc->tf.feature >> 4;
2623
2624	ata_qc_reinit(qc);
2625
2626	/* setup sg table and init transfer direction */
2627	sg_init_one(&qc->sgent, cmd->sense_buffer, SCSI_SENSE_BUFFERSIZE);
2628	ata_sg_init(qc, &qc->sgent, 1);
2629	qc->dma_dir = DMA_FROM_DEVICE;
2630
2631	memset(&qc->cdb, 0, qc->dev->cdb_len);
2632	qc->cdb[0] = REQUEST_SENSE;
2633	qc->cdb[4] = SCSI_SENSE_BUFFERSIZE;
2634
2635	qc->tf.flags |= ATA_TFLAG_ISADDR | ATA_TFLAG_DEVICE;
2636	qc->tf.command = ATA_CMD_PACKET;
2637
2638	if (ata_pio_use_silly(ap)) {
2639		qc->tf.protocol = ATAPI_PROT_DMA;
2640		qc->tf.feature |= ATAPI_PKT_DMA;
2641	} else {
2642		qc->tf.protocol = ATAPI_PROT_PIO;
2643		qc->tf.lbam = SCSI_SENSE_BUFFERSIZE;
2644		qc->tf.lbah = 0;
2645	}
2646	qc->nbytes = SCSI_SENSE_BUFFERSIZE;
2647
2648	qc->complete_fn = atapi_sense_complete;
2649
2650	ata_qc_issue(qc);
2651
2652	DPRINTK("EXIT\n");
2653}
2654
2655static void atapi_qc_complete(struct ata_queued_cmd *qc)
2656{
2657	struct scsi_cmnd *cmd = qc->scsicmd;
2658	unsigned int err_mask = qc->err_mask;
2659
2660	VPRINTK("ENTER, err_mask 0x%X\n", err_mask);
2661
2662	/* handle completion from new EH */
2663	if (unlikely(qc->ap->ops->error_handler &&
2664		     (err_mask || qc->flags & ATA_QCFLAG_SENSE_VALID))) {
2665
2666		if (!(qc->flags & ATA_QCFLAG_SENSE_VALID)) {
2667			/* FIXME: not quite right; we don't want the
2668			 * translation of taskfile registers into a
2669			 * sense descriptors, since that's only
2670			 * correct for ATA, not ATAPI
2671			 */
2672			ata_gen_passthru_sense(qc);
2673		}
2674
2675		/* SCSI EH automatically locks door if sdev->locked is
2676		 * set.  Sometimes door lock request continues to
2677		 * fail, for example, when no media is present.  This
2678		 * creates a loop - SCSI EH issues door lock which
2679		 * fails and gets invoked again to acquire sense data
2680		 * for the failed command.
2681		 *
2682		 * If door lock fails, always clear sdev->locked to
2683		 * avoid this infinite loop.
2684		 *
2685		 * This may happen before SCSI scan is complete.  Make
2686		 * sure qc->dev->sdev isn't NULL before dereferencing.
2687		 */
2688		if (qc->cdb[0] == ALLOW_MEDIUM_REMOVAL && qc->dev->sdev)
2689			qc->dev->sdev->locked = 0;
2690
2691		qc->scsicmd->result = SAM_STAT_CHECK_CONDITION;
2692		qc->scsidone(cmd);
2693		ata_qc_free(qc);
2694		return;
2695	}
2696
2697	/* successful completion or old EH failure path */
2698	if (unlikely(err_mask & AC_ERR_DEV)) {
2699		cmd->result = SAM_STAT_CHECK_CONDITION;
2700		atapi_request_sense(qc);
2701		return;
2702	} else if (unlikely(err_mask)) {
2703		/* FIXME: not quite right; we don't want the
2704		 * translation of taskfile registers into
2705		 * a sense descriptors, since that's only
2706		 * correct for ATA, not ATAPI
2707		 */
2708		ata_gen_passthru_sense(qc);
2709	} else {
2710		u8 *scsicmd = cmd->cmnd;
2711
2712		if ((scsicmd[0] == INQUIRY) && ((scsicmd[1] & 0x03) == 0)) {
2713			unsigned long flags;
2714			u8 *buf;
2715
2716			buf = ata_scsi_rbuf_get(cmd, true, &flags);
2717
2718	/* ATAPI devices typically report zero for their SCSI version,
2719	 * and sometimes deviate from the spec WRT response data
2720	 * format.  If SCSI version is reported as zero like normal,
2721	 * then we make the following fixups:  1) Fake MMC-5 version,
2722	 * to indicate to the Linux scsi midlayer this is a modern
2723	 * device.  2) Ensure response data format / ATAPI information
2724	 * are always correct.
2725	 */
2726			if (buf[2] == 0) {
2727				buf[2] = 0x5;
2728				buf[3] = 0x32;
2729			}
2730
2731			ata_scsi_rbuf_put(cmd, true, &flags);
2732		}
2733
2734		cmd->result = SAM_STAT_GOOD;
2735	}
2736
2737	qc->scsidone(cmd);
2738	ata_qc_free(qc);
2739}
2740/**
2741 *	atapi_xlat - Initialize PACKET taskfile
2742 *	@qc: command structure to be initialized
2743 *
2744 *	LOCKING:
2745 *	spin_lock_irqsave(host lock)
2746 *
2747 *	RETURNS:
2748 *	Zero on success, non-zero on failure.
2749 */
2750static unsigned int atapi_xlat(struct ata_queued_cmd *qc)
2751{
2752	struct scsi_cmnd *scmd = qc->scsicmd;
2753	struct ata_device *dev = qc->dev;
2754	int nodata = (scmd->sc_data_direction == DMA_NONE);
2755	int using_pio = !nodata && (dev->flags & ATA_DFLAG_PIO);
2756	unsigned int nbytes;
2757
2758	memset(qc->cdb, 0, dev->cdb_len);
2759	memcpy(qc->cdb, scmd->cmnd, scmd->cmd_len);
2760
2761	qc->complete_fn = atapi_qc_complete;
2762
2763	qc->tf.flags |= ATA_TFLAG_ISADDR | ATA_TFLAG_DEVICE;
2764	if (scmd->sc_data_direction == DMA_TO_DEVICE) {
2765		qc->tf.flags |= ATA_TFLAG_WRITE;
2766		DPRINTK("direction: write\n");
2767	}
2768
2769	qc->tf.command = ATA_CMD_PACKET;
2770	ata_qc_set_pc_nbytes(qc);
2771
2772	/* check whether ATAPI DMA is safe */
2773	if (!nodata && !using_pio && atapi_check_dma(qc))
2774		using_pio = 1;
2775
2776	/* Some controller variants snoop this value for Packet
2777	 * transfers to do state machine and FIFO management.  Thus we
2778	 * want to set it properly, and for DMA where it is
2779	 * effectively meaningless.
2780	 */
2781	nbytes = min(ata_qc_raw_nbytes(qc), (unsigned int)63 * 1024);
2782
2783	/* Most ATAPI devices which honor transfer chunk size don't
2784	 * behave according to the spec when odd chunk size which
2785	 * matches the transfer length is specified.  If the number of
2786	 * bytes to transfer is 2n+1.  According to the spec, what
2787	 * should happen is to indicate that 2n+1 is going to be
2788	 * transferred and transfer 2n+2 bytes where the last byte is
2789	 * padding.
2790	 *
2791	 * In practice, this doesn't happen.  ATAPI devices first
2792	 * indicate and transfer 2n bytes and then indicate and
2793	 * transfer 2 bytes where the last byte is padding.
2794	 *
2795	 * This inconsistency confuses several controllers which
2796	 * perform PIO using DMA such as Intel AHCIs and sil3124/32.
2797	 * These controllers use actual number of transferred bytes to
2798	 * update DMA poitner and transfer of 4n+2 bytes make those
2799	 * controller push DMA pointer by 4n+4 bytes because SATA data
2800	 * FISes are aligned to 4 bytes.  This causes data corruption
2801	 * and buffer overrun.
2802	 *
2803	 * Always setting nbytes to even number solves this problem
2804	 * because then ATAPI devices don't have to split data at 2n
2805	 * boundaries.
2806	 */
2807	if (nbytes & 0x1)
2808		nbytes++;
2809
2810	qc->tf.lbam = (nbytes & 0xFF);
2811	qc->tf.lbah = (nbytes >> 8);
2812
2813	if (nodata)
2814		qc->tf.protocol = ATAPI_PROT_NODATA;
2815	else if (using_pio)
2816		qc->tf.protocol = ATAPI_PROT_PIO;
2817	else {
2818		/* DMA data xfer */
2819		qc->tf.protocol = ATAPI_PROT_DMA;
2820		qc->tf.feature |= ATAPI_PKT_DMA;
2821
2822		if ((dev->flags & ATA_DFLAG_DMADIR) &&
2823		    (scmd->sc_data_direction != DMA_TO_DEVICE))
2824			/* some SATA bridges need us to indicate data xfer direction */
2825			qc->tf.feature |= ATAPI_DMADIR;
2826	}
2827
2828
2829	/* FIXME: We need to translate 0x05 READ_BLOCK_LIMITS to a MODE_SENSE
2830	   as ATAPI tape drives don't get this right otherwise */
2831	return 0;
2832}
2833
2834static struct ata_device *ata_find_dev(struct ata_port *ap, int devno)
2835{
2836	if (!sata_pmp_attached(ap)) {
2837		if (likely(devno < ata_link_max_devices(&ap->link)))
2838			return &ap->link.device[devno];
2839	} else {
2840		if (likely(devno < ap->nr_pmp_links))
2841			return &ap->pmp_link[devno].device[0];
2842	}
2843
2844	return NULL;
2845}
2846
2847static struct ata_device *__ata_scsi_find_dev(struct ata_port *ap,
2848					      const struct scsi_device *scsidev)
2849{
2850	int devno;
2851
2852	/* skip commands not addressed to targets we simulate */
2853	if (!sata_pmp_attached(ap)) {
2854		if (unlikely(scsidev->channel || scsidev->lun))
2855			return NULL;
2856		devno = scsidev->id;
2857	} else {
2858		if (unlikely(scsidev->id || scsidev->lun))
2859			return NULL;
2860		devno = scsidev->channel;
2861	}
2862
2863	return ata_find_dev(ap, devno);
2864}
2865
2866/**
2867 *	ata_scsi_find_dev - lookup ata_device from scsi_cmnd
2868 *	@ap: ATA port to which the device is attached
2869 *	@scsidev: SCSI device from which we derive the ATA device
2870 *
2871 *	Given various information provided in struct scsi_cmnd,
2872 *	map that onto an ATA bus, and using that mapping
2873 *	determine which ata_device is associated with the
2874 *	SCSI command to be sent.
2875 *
2876 *	LOCKING:
2877 *	spin_lock_irqsave(host lock)
2878 *
2879 *	RETURNS:
2880 *	Associated ATA device, or %NULL if not found.
2881 */
2882static struct ata_device *
2883ata_scsi_find_dev(struct ata_port *ap, const struct scsi_device *scsidev)
2884{
2885	struct ata_device *dev = __ata_scsi_find_dev(ap, scsidev);
2886
2887	if (unlikely(!dev || !ata_dev_enabled(dev)))
2888		return NULL;
2889
2890	return dev;
2891}
2892
2893/*
2894 *	ata_scsi_map_proto - Map pass-thru protocol value to taskfile value.
2895 *	@byte1: Byte 1 from pass-thru CDB.
2896 *
2897 *	RETURNS:
2898 *	ATA_PROT_UNKNOWN if mapping failed/unimplemented, protocol otherwise.
2899 */
2900static u8
2901ata_scsi_map_proto(u8 byte1)
2902{
2903	switch((byte1 & 0x1e) >> 1) {
2904	case 3:		/* Non-data */
2905		return ATA_PROT_NODATA;
2906
2907	case 6:		/* DMA */
2908	case 10:	/* UDMA Data-in */
2909	case 11:	/* UDMA Data-Out */
2910		return ATA_PROT_DMA;
2911
2912	case 4:		/* PIO Data-in */
2913	case 5:		/* PIO Data-out */
2914		return ATA_PROT_PIO;
2915
2916	case 0:		/* Hard Reset */
2917	case 1:		/* SRST */
2918	case 8:		/* Device Diagnostic */
2919	case 9:		/* Device Reset */
2920	case 7:		/* DMA Queued */
2921	case 12:	/* FPDMA */
2922	case 15:	/* Return Response Info */
2923	default:	/* Reserved */
2924		break;
2925	}
2926
2927	return ATA_PROT_UNKNOWN;
2928}
2929
2930/**
2931 *	ata_scsi_pass_thru - convert ATA pass-thru CDB to taskfile
2932 *	@qc: command structure to be initialized
2933 *
2934 *	Handles either 12 or 16-byte versions of the CDB.
2935 *
2936 *	RETURNS:
2937 *	Zero on success, non-zero on failure.
2938 */
2939static unsigned int ata_scsi_pass_thru(struct ata_queued_cmd *qc)
2940{
2941	struct ata_taskfile *tf = &(qc->tf);
2942	struct scsi_cmnd *scmd = qc->scsicmd;
2943	struct ata_device *dev = qc->dev;
2944	const u8 *cdb = scmd->cmnd;
2945
2946	if ((tf->protocol = ata_scsi_map_proto(cdb[1])) == ATA_PROT_UNKNOWN)
2947		goto invalid_fld;
2948
2949	/*
2950	 * 12 and 16 byte CDBs use different offsets to
2951	 * provide the various register values.
2952	 */
2953	if (cdb[0] == ATA_16) {
2954		/*
2955		 * 16-byte CDB - may contain extended commands.
2956		 *
2957		 * If that is the case, copy the upper byte register values.
2958		 */
2959		if (cdb[1] & 0x01) {
2960			tf->hob_feature = cdb[3];
2961			tf->hob_nsect = cdb[5];
2962			tf->hob_lbal = cdb[7];
2963			tf->hob_lbam = cdb[9];
2964			tf->hob_lbah = cdb[11];
2965			tf->flags |= ATA_TFLAG_LBA48;
2966		} else
2967			tf->flags &= ~ATA_TFLAG_LBA48;
2968
2969		/*
2970		 * Always copy low byte, device and command registers.
2971		 */
2972		tf->feature = cdb[4];
2973		tf->nsect = cdb[6];
2974		tf->lbal = cdb[8];
2975		tf->lbam = cdb[10];
2976		tf->lbah = cdb[12];
2977		tf->device = cdb[13];
2978		tf->command = cdb[14];
2979	} else {
2980		/*
2981		 * 12-byte CDB - incapable of extended commands.
2982		 */
2983		tf->flags &= ~ATA_TFLAG_LBA48;
2984
2985		tf->feature = cdb[3];
2986		tf->nsect = cdb[4];
2987		tf->lbal = cdb[5];
2988		tf->lbam = cdb[6];
2989		tf->lbah = cdb[7];
2990		tf->device = cdb[8];
2991		tf->command = cdb[9];
2992	}
2993
2994	/* enforce correct master/slave bit */
2995	tf->device = dev->devno ?
2996		tf->device | ATA_DEV1 : tf->device & ~ATA_DEV1;
2997
2998	switch (tf->command) {
2999	/* READ/WRITE LONG use a non-standard sect_size */
3000	case ATA_CMD_READ_LONG:
3001	case ATA_CMD_READ_LONG_ONCE:
3002	case ATA_CMD_WRITE_LONG:
3003	case ATA_CMD_WRITE_LONG_ONCE:
3004		if (tf->protocol != ATA_PROT_PIO || tf->nsect != 1)
3005			goto invalid_fld;
3006		qc->sect_size = scsi_bufflen(scmd);
3007		break;
3008
3009	/* commands using reported Logical Block size (e.g. 512 or 4K) */
3010	case ATA_CMD_CFA_WRITE_NE:
3011	case ATA_CMD_CFA_TRANS_SECT:
3012	case ATA_CMD_CFA_WRITE_MULT_NE:
3013	/* XXX: case ATA_CMD_CFA_WRITE_SECTORS_WITHOUT_ERASE: */
3014	case ATA_CMD_READ:
3015	case ATA_CMD_READ_EXT:
3016	case ATA_CMD_READ_QUEUED:
3017	/* XXX: case ATA_CMD_READ_QUEUED_EXT: */
3018	case ATA_CMD_FPDMA_READ:
3019	case ATA_CMD_READ_MULTI:
3020	case ATA_CMD_READ_MULTI_EXT:
3021	case ATA_CMD_PIO_READ:
3022	case ATA_CMD_PIO_READ_EXT:
3023	case ATA_CMD_READ_STREAM_DMA_EXT:
3024	case ATA_CMD_READ_STREAM_EXT:
3025	case ATA_CMD_VERIFY:
3026	case ATA_CMD_VERIFY_EXT:
3027	case ATA_CMD_WRITE:
3028	case ATA_CMD_WRITE_EXT:
3029	case ATA_CMD_WRITE_FUA_EXT:
3030	case ATA_CMD_WRITE_QUEUED:
3031	case ATA_CMD_WRITE_QUEUED_FUA_EXT:
3032	case ATA_CMD_FPDMA_WRITE:
3033	case ATA_CMD_WRITE_MULTI:
3034	case ATA_CMD_WRITE_MULTI_EXT:
3035	case ATA_CMD_WRITE_MULTI_FUA_EXT:
3036	case ATA_CMD_PIO_WRITE:
3037	case ATA_CMD_PIO_WRITE_EXT:
3038	case ATA_CMD_WRITE_STREAM_DMA_EXT:
3039	case ATA_CMD_WRITE_STREAM_EXT:
3040		qc->sect_size = scmd->device->sector_size;
3041		break;
3042
3043	/* Everything else uses 512 byte "sectors" */
3044	default:
3045		qc->sect_size = ATA_SECT_SIZE;
3046	}
3047
3048	/*
3049	 * Set flags so that all registers will be written, pass on
3050	 * write indication (used for PIO/DMA setup), result TF is
3051	 * copied back and we don't whine too much about its failure.
3052	 */
3053	tf->flags |= ATA_TFLAG_ISADDR | ATA_TFLAG_DEVICE;
3054	if (scmd->sc_data_direction == DMA_TO_DEVICE)
3055		tf->flags |= ATA_TFLAG_WRITE;
3056
3057	qc->flags |= ATA_QCFLAG_RESULT_TF | ATA_QCFLAG_QUIET;
3058
3059	/*
3060	 * Set transfer length.
3061	 *
3062	 * TODO: find out if we need to do more here to
3063	 *       cover scatter/gather case.
3064	 */
3065	ata_qc_set_pc_nbytes(qc);
3066
3067	/* We may not issue DMA commands if no DMA mode is set */
3068	if (tf->protocol == ATA_PROT_DMA && dev->dma_mode == 0)
3069		goto invalid_fld;
3070
3071	/* sanity check for pio multi commands */
3072	if ((cdb[1] & 0xe0) && !is_multi_taskfile(tf))
3073		goto invalid_fld;
3074
3075	if (is_multi_taskfile(tf)) {
3076		unsigned int multi_count = 1 << (cdb[1] >> 5);
3077
3078		/* compare the passed through multi_count
3079		 * with the cached multi_count of libata
3080		 */
3081		if (multi_count != dev->multi_count)
3082			ata_dev_warn(dev, "invalid multi_count %u ignored\n",
3083				     multi_count);
3084	}
3085
3086	/*
3087	 * Filter SET_FEATURES - XFER MODE command -- otherwise,
3088	 * SET_FEATURES - XFER MODE must be preceded/succeeded
3089	 * by an update to hardware-specific registers for each
3090	 * controller (i.e. the reason for ->set_piomode(),
3091	 * ->set_dmamode(), and ->post_set_mode() hooks).
3092	 */
3093	if (tf->command == ATA_CMD_SET_FEATURES &&
3094	    tf->feature == SETFEATURES_XFER)
3095		goto invalid_fld;
3096
3097	/*
3098	 * Filter TPM commands by default. These provide an
3099	 * essentially uncontrolled encrypted "back door" between
3100	 * applications and the disk. Set libata.allow_tpm=1 if you
3101	 * have a real reason for wanting to use them. This ensures
3102	 * that installed software cannot easily mess stuff up without
3103	 * user intent. DVR type users will probably ship with this enabled
3104	 * for movie content management.
3105	 *
3106	 * Note that for ATA8 we can issue a DCS change and DCS freeze lock
3107	 * for this and should do in future but that it is not sufficient as
3108	 * DCS is an optional feature set. Thus we also do the software filter
3109	 * so that we comply with the TC consortium stated goal that the user
3110	 * can turn off TC features of their system.
3111	 */
3112	if (tf->command >= 0x5C && tf->command <= 0x5F && !libata_allow_tpm)
3113		goto invalid_fld;
3114
3115	return 0;
3116
3117 invalid_fld:
3118	ata_scsi_set_sense(scmd, ILLEGAL_REQUEST, 0x24, 0x00);
3119	/* "Invalid field in cdb" */
3120	return 1;
3121}
3122
3123static unsigned int ata_scsi_write_same_xlat(struct ata_queued_cmd *qc)
3124{
3125	struct ata_taskfile *tf = &qc->tf;
3126	struct scsi_cmnd *scmd = qc->scsicmd;
3127	struct ata_device *dev = qc->dev;
3128	const u8 *cdb = scmd->cmnd;
3129	u64 block;
3130	u32 n_block;
3131	u32 size;
3132	void *buf;
3133
3134	/* we may not issue DMA commands if no DMA mode is set */
3135	if (unlikely(!dev->dma_mode))
3136		goto invalid_fld;
3137
3138	if (unlikely(scmd->cmd_len < 16))
3139		goto invalid_fld;
3140	scsi_16_lba_len(cdb, &block, &n_block);
3141
3142	/* for now we only support WRITE SAME with the unmap bit set */
3143	if (unlikely(!(cdb[1] & 0x8)))
3144		goto invalid_fld;
3145
3146	/*
3147	 * WRITE SAME always has a sector sized buffer as payload, this
3148	 * should never be a multiple entry S/G list.
3149	 */
3150	if (!scsi_sg_count(scmd))
3151		goto invalid_fld;
3152
3153	buf = page_address(sg_page(scsi_sglist(scmd)));
3154	size = ata_set_lba_range_entries(buf, 512, block, n_block);
3155
3156	if (ata_ncq_enabled(dev) && ata_fpdma_dsm_supported(dev)) {
3157		/* Newer devices support queued TRIM commands */
3158		tf->protocol = ATA_PROT_NCQ;
3159		tf->command = ATA_CMD_FPDMA_SEND;
3160		tf->hob_nsect = ATA_SUBCMD_FPDMA_SEND_DSM & 0x1f;
3161		tf->nsect = qc->tag << 3;
3162		tf->hob_feature = (size / 512) >> 8;
3163		tf->feature = size / 512;
3164
3165		tf->auxiliary = 1;
3166	} else {
3167		tf->protocol = ATA_PROT_DMA;
3168		tf->hob_feature = 0;
3169		tf->feature = ATA_DSM_TRIM;
3170		tf->hob_nsect = (size / 512) >> 8;
3171		tf->nsect = size / 512;
3172		tf->command = ATA_CMD_DSM;
3173	}
3174
3175	tf->flags |= ATA_TFLAG_ISADDR | ATA_TFLAG_DEVICE | ATA_TFLAG_LBA48 |
3176		     ATA_TFLAG_WRITE;
3177
3178	ata_qc_set_pc_nbytes(qc);
3179
3180	return 0;
3181
3182 invalid_fld:
3183	ata_scsi_set_sense(scmd, ILLEGAL_REQUEST, 0x24, 0x00);
3184	/* "Invalid field in cdb" */
3185	return 1;
3186}
3187
3188/**
3189 *	ata_mselect_caching - Simulate MODE SELECT for caching info page
3190 *	@qc: Storage for translated ATA taskfile
3191 *	@buf: input buffer
3192 *	@len: number of valid bytes in the input buffer
3193 *
3194 *	Prepare a taskfile to modify caching information for the device.
3195 *
3196 *	LOCKING:
3197 *	None.
3198 */
3199static int ata_mselect_caching(struct ata_queued_cmd *qc,
3200			       const u8 *buf, int len)
3201{
3202	struct ata_taskfile *tf = &qc->tf;
3203	struct ata_device *dev = qc->dev;
3204	char mpage[CACHE_MPAGE_LEN];
3205	u8 wce;
3206
3207	/*
3208	 * The first two bytes of def_cache_mpage are a header, so offsets
3209	 * in mpage are off by 2 compared to buf.  Same for len.
3210	 */
3211
3212	if (len != CACHE_MPAGE_LEN - 2)
3213		return -EINVAL;
3214
3215	wce = buf[0] & (1 << 2);
3216
3217	/*
3218	 * Check that read-only bits are not modified.
3219	 */
3220	ata_msense_caching(dev->id, mpage, false);
3221	mpage[2] &= ~(1 << 2);
3222	mpage[2] |= wce;
3223	if (memcmp(mpage + 2, buf, CACHE_MPAGE_LEN - 2) != 0)
3224		return -EINVAL;
3225
3226	tf->flags |= ATA_TFLAG_DEVICE | ATA_TFLAG_ISADDR;
3227	tf->protocol = ATA_PROT_NODATA;
3228	tf->nsect = 0;
3229	tf->command = ATA_CMD_SET_FEATURES;
3230	tf->feature = wce ? SETFEATURES_WC_ON : SETFEATURES_WC_OFF;
3231	return 0;
3232}
3233
3234/**
3235 *	ata_scsiop_mode_select - Simulate MODE SELECT 6, 10 commands
3236 *	@qc: Storage for translated ATA taskfile
3237 *
3238 *	Converts a MODE SELECT command to an ATA SET FEATURES taskfile.
3239 *	Assume this is invoked for direct access devices (e.g. disks) only.
3240 *	There should be no block descriptor for other device types.
3241 *
3242 *	LOCKING:
3243 *	spin_lock_irqsave(host lock)
3244 */
3245static unsigned int ata_scsi_mode_select_xlat(struct ata_queued_cmd *qc)
3246{
3247	struct scsi_cmnd *scmd = qc->scsicmd;
3248	const u8 *cdb = scmd->cmnd;
3249	const u8 *p;
3250	u8 pg, spg;
3251	unsigned six_byte, pg_len, hdr_len, bd_len;
3252	int len;
3253
3254	VPRINTK("ENTER\n");
3255
3256	six_byte = (cdb[0] == MODE_SELECT);
3257	if (six_byte) {
3258		if (scmd->cmd_len < 5)
3259			goto invalid_fld;
3260
3261		len = cdb[4];
3262		hdr_len = 4;
3263	} else {
3264		if (scmd->cmd_len < 9)
3265			goto invalid_fld;
3266
3267		len = (cdb[7] << 8) + cdb[8];
3268		hdr_len = 8;
3269	}
3270
3271	/* We only support PF=1, SP=0.  */
3272	if ((cdb[1] & 0x11) != 0x10)
3273		goto invalid_fld;
3274
3275	/* Test early for possible overrun.  */
3276	if (!scsi_sg_count(scmd) || scsi_sglist(scmd)->length < len)
3277		goto invalid_param_len;
3278
3279	p = page_address(sg_page(scsi_sglist(scmd)));
3280
3281	/* Move past header and block descriptors.  */
3282	if (len < hdr_len)
3283		goto invalid_param_len;
3284
3285	if (six_byte)
3286		bd_len = p[3];
3287	else
3288		bd_len = (p[6] << 8) + p[7];
3289
3290	len -= hdr_len;
3291	p += hdr_len;
3292	if (len < bd_len)
3293		goto invalid_param_len;
3294	if (bd_len != 0 && bd_len != 8)
3295		goto invalid_param;
3296
3297	len -= bd_len;
3298	p += bd_len;
3299	if (len == 0)
3300		goto skip;
3301
3302	/* Parse both possible formats for the mode page headers.  */
3303	pg = p[0] & 0x3f;
3304	if (p[0] & 0x40) {
3305		if (len < 4)
3306			goto invalid_param_len;
3307
3308		spg = p[1];
3309		pg_len = (p[2] << 8) | p[3];
3310		p += 4;
3311		len -= 4;
3312	} else {
3313		if (len < 2)
3314			goto invalid_param_len;
3315
3316		spg = 0;
3317		pg_len = p[1];
3318		p += 2;
3319		len -= 2;
3320	}
3321
3322	/*
3323	 * No mode subpages supported (yet) but asking for _all_
3324	 * subpages may be valid
3325	 */
3326	if (spg && (spg != ALL_SUB_MPAGES))
3327		goto invalid_param;
3328	if (pg_len > len)
3329		goto invalid_param_len;
3330
3331	switch (pg) {
3332	case CACHE_MPAGE:
3333		if (ata_mselect_caching(qc, p, pg_len) < 0)
3334			goto invalid_param;
3335		break;
3336
3337	default:		/* invalid page code */
3338		goto invalid_param;
3339	}
3340
3341	/*
3342	 * Only one page has changeable data, so we only support setting one
3343	 * page at a time.
3344	 */
3345	if (len > pg_len)
3346		goto invalid_param;
3347
3348	return 0;
3349
3350 invalid_fld:
3351	/* "Invalid field in CDB" */
3352	ata_scsi_set_sense(scmd, ILLEGAL_REQUEST, 0x24, 0x0);
3353	return 1;
3354
3355 invalid_param:
3356	/* "Invalid field in parameter list" */
3357	ata_scsi_set_sense(scmd, ILLEGAL_REQUEST, 0x26, 0x0);
3358	return 1;
3359
3360 invalid_param_len:
3361	/* "Parameter list length error" */
3362	ata_scsi_set_sense(scmd, ILLEGAL_REQUEST, 0x1a, 0x0);
3363	return 1;
3364
3365 skip:
3366	scmd->result = SAM_STAT_GOOD;
3367	return 1;
3368}
3369
3370/**
3371 *	ata_get_xlat_func - check if SCSI to ATA translation is possible
3372 *	@dev: ATA device
3373 *	@cmd: SCSI command opcode to consider
3374 *
3375 *	Look up the SCSI command given, and determine whether the
3376 *	SCSI command is to be translated or simulated.
3377 *
3378 *	RETURNS:
3379 *	Pointer to translation function if possible, %NULL if not.
3380 */
3381
3382static inline ata_xlat_func_t ata_get_xlat_func(struct ata_device *dev, u8 cmd)
3383{
3384	switch (cmd) {
3385	case READ_6:
3386	case READ_10:
3387	case READ_16:
3388
3389	case WRITE_6:
3390	case WRITE_10:
3391	case WRITE_16:
3392		return ata_scsi_rw_xlat;
3393
3394	case WRITE_SAME_16:
3395		return ata_scsi_write_same_xlat;
3396
3397	case SYNCHRONIZE_CACHE:
3398		if (ata_try_flush_cache(dev))
3399			return ata_scsi_flush_xlat;
3400		break;
3401
3402	case VERIFY:
3403	case VERIFY_16:
3404		return ata_scsi_verify_xlat;
3405
3406	case ATA_12:
3407	case ATA_16:
3408		return ata_scsi_pass_thru;
3409
3410	case MODE_SELECT:
3411	case MODE_SELECT_10:
3412		return ata_scsi_mode_select_xlat;
3413		break;
3414
3415	case START_STOP:
3416		return ata_scsi_start_stop_xlat;
3417	}
3418
3419	return NULL;
3420}
3421
3422/**
3423 *	ata_scsi_dump_cdb - dump SCSI command contents to dmesg
3424 *	@ap: ATA port to which the command was being sent
3425 *	@cmd: SCSI command to dump
3426 *
3427 *	Prints the contents of a SCSI command via printk().
3428 */
3429
3430static inline void ata_scsi_dump_cdb(struct ata_port *ap,
3431				     struct scsi_cmnd *cmd)
3432{
3433#ifdef ATA_DEBUG
3434	struct scsi_device *scsidev = cmd->device;
3435	u8 *scsicmd = cmd->cmnd;
3436
3437	DPRINTK("CDB (%u:%d,%d,%d) %02x %02x %02x %02x %02x %02x %02x %02x %02x\n",
3438		ap->print_id,
3439		scsidev->channel, scsidev->id, scsidev->lun,
3440		scsicmd[0], scsicmd[1], scsicmd[2], scsicmd[3],
3441		scsicmd[4], scsicmd[5], scsicmd[6], scsicmd[7],
3442		scsicmd[8]);
3443#endif
3444}
3445
3446static inline int __ata_scsi_queuecmd(struct scsi_cmnd *scmd,
3447				      struct ata_device *dev)
3448{
3449	u8 scsi_op = scmd->cmnd[0];
3450	ata_xlat_func_t xlat_func;
3451	int rc = 0;
3452
3453	if (dev->class == ATA_DEV_ATA || dev->class == ATA_DEV_ZAC) {
3454		if (unlikely(!scmd->cmd_len || scmd->cmd_len > dev->cdb_len))
3455			goto bad_cdb_len;
3456
3457		xlat_func = ata_get_xlat_func(dev, scsi_op);
3458	} else {
3459		if (unlikely(!scmd->cmd_len))
3460			goto bad_cdb_len;
3461
3462		xlat_func = NULL;
3463		if (likely((scsi_op != ATA_16) || !atapi_passthru16)) {
3464			/* relay SCSI command to ATAPI device */
3465			int len = COMMAND_SIZE(scsi_op);
3466			if (unlikely(len > scmd->cmd_len || len > dev->cdb_len))
3467				goto bad_cdb_len;
3468
3469			xlat_func = atapi_xlat;
3470		} else {
3471			/* ATA_16 passthru, treat as an ATA command */
3472			if (unlikely(scmd->cmd_len > 16))
3473				goto bad_cdb_len;
3474
3475			xlat_func = ata_get_xlat_func(dev, scsi_op);
3476		}
3477	}
3478
3479	if (xlat_func)
3480		rc = ata_scsi_translate(dev, scmd, xlat_func);
3481	else
3482		ata_scsi_simulate(dev, scmd);
3483
3484	return rc;
3485
3486 bad_cdb_len:
3487	DPRINTK("bad CDB len=%u, scsi_op=0x%02x, max=%u\n",
3488		scmd->cmd_len, scsi_op, dev->cdb_len);
3489	scmd->result = DID_ERROR << 16;
3490	scmd->scsi_done(scmd);
3491	return 0;
3492}
3493
3494/**
3495 *	ata_scsi_queuecmd - Issue SCSI cdb to libata-managed device
3496 *	@shost: SCSI host of command to be sent
3497 *	@cmd: SCSI command to be sent
3498 *
3499 *	In some cases, this function translates SCSI commands into
3500 *	ATA taskfiles, and queues the taskfiles to be sent to
3501 *	hardware.  In other cases, this function simulates a
3502 *	SCSI device by evaluating and responding to certain
3503 *	SCSI commands.  This creates the overall effect of
3504 *	ATA and ATAPI devices appearing as SCSI devices.
3505 *
3506 *	LOCKING:
3507 *	ATA host lock
3508 *
3509 *	RETURNS:
3510 *	Return value from __ata_scsi_queuecmd() if @cmd can be queued,
3511 *	0 otherwise.
3512 */
3513int ata_scsi_queuecmd(struct Scsi_Host *shost, struct scsi_cmnd *cmd)
3514{
3515	struct ata_port *ap;
3516	struct ata_device *dev;
3517	struct scsi_device *scsidev = cmd->device;
3518	int rc = 0;
3519	unsigned long irq_flags;
3520
3521	ap = ata_shost_to_port(shost);
3522
3523	spin_lock_irqsave(ap->lock, irq_flags);
3524
3525	ata_scsi_dump_cdb(ap, cmd);
3526
3527	dev = ata_scsi_find_dev(ap, scsidev);
3528	if (likely(dev))
3529		rc = __ata_scsi_queuecmd(cmd, dev);
3530	else {
3531		cmd->result = (DID_BAD_TARGET << 16);
3532		cmd->scsi_done(cmd);
3533	}
3534
3535	spin_unlock_irqrestore(ap->lock, irq_flags);
3536
3537	return rc;
3538}
3539
3540/**
3541 *	ata_scsi_simulate - simulate SCSI command on ATA device
3542 *	@dev: the target device
3543 *	@cmd: SCSI command being sent to device.
3544 *
3545 *	Interprets and directly executes a select list of SCSI commands
3546 *	that can be handled internally.
3547 *
3548 *	LOCKING:
3549 *	spin_lock_irqsave(host lock)
3550 */
3551
3552void ata_scsi_simulate(struct ata_device *dev, struct scsi_cmnd *cmd)
3553{
3554	struct ata_scsi_args args;
3555	const u8 *scsicmd = cmd->cmnd;
3556	u8 tmp8;
3557
3558	args.dev = dev;
3559	args.id = dev->id;
3560	args.cmd = cmd;
3561	args.done = cmd->scsi_done;
3562
3563	switch(scsicmd[0]) {
3564	/* TODO: worth improving? */
3565	case FORMAT_UNIT:
3566		ata_scsi_invalid_field(cmd);
3567		break;
3568
3569	case INQUIRY:
3570		if (scsicmd[1] & 2)	           /* is CmdDt set?  */
3571			ata_scsi_invalid_field(cmd);
3572		else if ((scsicmd[1] & 1) == 0)    /* is EVPD clear? */
3573			ata_scsi_rbuf_fill(&args, ata_scsiop_inq_std);
3574		else switch (scsicmd[2]) {
3575		case 0x00:
3576			ata_scsi_rbuf_fill(&args, ata_scsiop_inq_00);
3577			break;
3578		case 0x80:
3579			ata_scsi_rbuf_fill(&args, ata_scsiop_inq_80);
3580			break;
3581		case 0x83:
3582			ata_scsi_rbuf_fill(&args, ata_scsiop_inq_83);
3583			break;
3584		case 0x89:
3585			ata_scsi_rbuf_fill(&args, ata_scsiop_inq_89);
3586			break;
3587		case 0xb0:
3588			ata_scsi_rbuf_fill(&args, ata_scsiop_inq_b0);
3589			break;
3590		case 0xb1:
3591			ata_scsi_rbuf_fill(&args, ata_scsiop_inq_b1);
3592			break;
3593		case 0xb2:
3594			ata_scsi_rbuf_fill(&args, ata_scsiop_inq_b2);
3595			break;
3596		default:
3597			ata_scsi_invalid_field(cmd);
3598			break;
3599		}
3600		break;
3601
3602	case MODE_SENSE:
3603	case MODE_SENSE_10:
3604		ata_scsi_rbuf_fill(&args, ata_scsiop_mode_sense);
3605		break;
3606
3607	case READ_CAPACITY:
3608		ata_scsi_rbuf_fill(&args, ata_scsiop_read_cap);
3609		break;
3610
3611	case SERVICE_ACTION_IN_16:
3612		if ((scsicmd[1] & 0x1f) == SAI_READ_CAPACITY_16)
3613			ata_scsi_rbuf_fill(&args, ata_scsiop_read_cap);
3614		else
3615			ata_scsi_invalid_field(cmd);
3616		break;
3617
3618	case REPORT_LUNS:
3619		ata_scsi_rbuf_fill(&args, ata_scsiop_report_luns);
3620		break;
3621
3622	case REQUEST_SENSE:
3623		ata_scsi_set_sense(cmd, 0, 0, 0);
3624		cmd->result = (DRIVER_SENSE << 24);
3625		cmd->scsi_done(cmd);
3626		break;
3627
3628	/* if we reach this, then writeback caching is disabled,
3629	 * turning this into a no-op.
3630	 */
3631	case SYNCHRONIZE_CACHE:
3632		/* fall through */
3633
3634	/* no-op's, complete with success */
3635	case REZERO_UNIT:
3636	case SEEK_6:
3637	case SEEK_10:
3638	case TEST_UNIT_READY:
3639		ata_scsi_rbuf_fill(&args, ata_scsiop_noop);
3640		break;
3641
3642	case SEND_DIAGNOSTIC:
3643		tmp8 = scsicmd[1] & ~(1 << 3);
3644		if ((tmp8 == 0x4) && (!scsicmd[3]) && (!scsicmd[4]))
3645			ata_scsi_rbuf_fill(&args, ata_scsiop_noop);
3646		else
3647			ata_scsi_invalid_field(cmd);
3648		break;
3649
3650	/* all other commands */
3651	default:
3652		ata_scsi_set_sense(cmd, ILLEGAL_REQUEST, 0x20, 0x0);
3653		/* "Invalid command operation code" */
3654		cmd->scsi_done(cmd);
3655		break;
3656	}
3657}
3658
3659int ata_scsi_add_hosts(struct ata_host *host, struct scsi_host_template *sht)
3660{
3661	int i, rc;
3662
3663	for (i = 0; i < host->n_ports; i++) {
3664		struct ata_port *ap = host->ports[i];
3665		struct Scsi_Host *shost;
3666
3667		rc = -ENOMEM;
3668		shost = scsi_host_alloc(sht, sizeof(struct ata_port *));
3669		if (!shost)
3670			goto err_alloc;
3671
3672		shost->eh_noresume = 1;
3673		*(struct ata_port **)&shost->hostdata[0] = ap;
3674		ap->scsi_host = shost;
3675
3676		shost->transportt = ata_scsi_transport_template;
3677		shost->unique_id = ap->print_id;
3678		shost->max_id = 16;
3679		shost->max_lun = 1;
3680		shost->max_channel = 1;
3681		shost->max_cmd_len = 16;
3682		shost->no_write_same = 1;
3683
3684		/* Schedule policy is determined by ->qc_defer()
3685		 * callback and it needs to see every deferred qc.
3686		 * Set host_blocked to 1 to prevent SCSI midlayer from
3687		 * automatically deferring requests.
3688		 */
3689		shost->max_host_blocked = 1;
3690
3691		if (scsi_init_shared_tag_map(shost, host->n_tags))
3692			goto err_add;
3693
3694		rc = scsi_add_host_with_dma(ap->scsi_host,
3695						&ap->tdev, ap->host->dev);
3696		if (rc)
3697			goto err_add;
3698	}
3699
3700	return 0;
3701
3702 err_add:
3703	scsi_host_put(host->ports[i]->scsi_host);
3704 err_alloc:
3705	while (--i >= 0) {
3706		struct Scsi_Host *shost = host->ports[i]->scsi_host;
3707
3708		scsi_remove_host(shost);
3709		scsi_host_put(shost);
3710	}
3711	return rc;
3712}
3713
3714void ata_scsi_scan_host(struct ata_port *ap, int sync)
3715{
3716	int tries = 5;
3717	struct ata_device *last_failed_dev = NULL;
3718	struct ata_link *link;
3719	struct ata_device *dev;
3720
3721 repeat:
3722	ata_for_each_link(link, ap, EDGE) {
3723		ata_for_each_dev(dev, link, ENABLED) {
3724			struct scsi_device *sdev;
3725			int channel = 0, id = 0;
3726
3727			if (dev->sdev)
3728				continue;
3729
3730			if (ata_is_host_link(link))
3731				id = dev->devno;
3732			else
3733				channel = link->pmp;
3734
3735			sdev = __scsi_add_device(ap->scsi_host, channel, id, 0,
3736						 NULL);
3737			if (!IS_ERR(sdev)) {
3738				dev->sdev = sdev;
3739				scsi_device_put(sdev);
3740			} else {
3741				dev->sdev = NULL;
3742			}
3743		}
3744	}
3745
3746	/* If we scanned while EH was in progress or allocation
3747	 * failure occurred, scan would have failed silently.  Check
3748	 * whether all devices are attached.
3749	 */
3750	ata_for_each_link(link, ap, EDGE) {
3751		ata_for_each_dev(dev, link, ENABLED) {
3752			if (!dev->sdev)
3753				goto exit_loop;
3754		}
3755	}
3756 exit_loop:
3757	if (!link)
3758		return;
3759
3760	/* we're missing some SCSI devices */
3761	if (sync) {
3762		/* If caller requested synchrnous scan && we've made
3763		 * any progress, sleep briefly and repeat.
3764		 */
3765		if (dev != last_failed_dev) {
3766			msleep(100);
3767			last_failed_dev = dev;
3768			goto repeat;
3769		}
3770
3771		/* We might be failing to detect boot device, give it
3772		 * a few more chances.
3773		 */
3774		if (--tries) {
3775			msleep(100);
3776			goto repeat;
3777		}
3778
3779		ata_port_err(ap,
3780			     "WARNING: synchronous SCSI scan failed without making any progress, switching to async\n");
3781	}
3782
3783	queue_delayed_work(system_long_wq, &ap->hotplug_task,
3784			   round_jiffies_relative(HZ));
3785}
3786
3787/**
3788 *	ata_scsi_offline_dev - offline attached SCSI device
3789 *	@dev: ATA device to offline attached SCSI device for
3790 *
3791 *	This function is called from ata_eh_hotplug() and responsible
3792 *	for taking the SCSI device attached to @dev offline.  This
3793 *	function is called with host lock which protects dev->sdev
3794 *	against clearing.
3795 *
3796 *	LOCKING:
3797 *	spin_lock_irqsave(host lock)
3798 *
3799 *	RETURNS:
3800 *	1 if attached SCSI device exists, 0 otherwise.
3801 */
3802int ata_scsi_offline_dev(struct ata_device *dev)
3803{
3804	if (dev->sdev) {
3805		scsi_device_set_state(dev->sdev, SDEV_OFFLINE);
3806		return 1;
3807	}
3808	return 0;
3809}
3810
3811/**
3812 *	ata_scsi_remove_dev - remove attached SCSI device
3813 *	@dev: ATA device to remove attached SCSI device for
3814 *
3815 *	This function is called from ata_eh_scsi_hotplug() and
3816 *	responsible for removing the SCSI device attached to @dev.
3817 *
3818 *	LOCKING:
3819 *	Kernel thread context (may sleep).
3820 */
3821static void ata_scsi_remove_dev(struct ata_device *dev)
3822{
3823	struct ata_port *ap = dev->link->ap;
3824	struct scsi_device *sdev;
3825	unsigned long flags;
3826
3827	/* Alas, we need to grab scan_mutex to ensure SCSI device
3828	 * state doesn't change underneath us and thus
3829	 * scsi_device_get() always succeeds.  The mutex locking can
3830	 * be removed if there is __scsi_device_get() interface which
3831	 * increments reference counts regardless of device state.
3832	 */
3833	mutex_lock(&ap->scsi_host->scan_mutex);
3834	spin_lock_irqsave(ap->lock, flags);
3835
3836	/* clearing dev->sdev is protected by host lock */
3837	sdev = dev->sdev;
3838	dev->sdev = NULL;
3839
3840	if (sdev) {
3841		/* If user initiated unplug races with us, sdev can go
3842		 * away underneath us after the host lock and
3843		 * scan_mutex are released.  Hold onto it.
3844		 */
3845		if (scsi_device_get(sdev) == 0) {
3846			/* The following ensures the attached sdev is
3847			 * offline on return from ata_scsi_offline_dev()
3848			 * regardless it wins or loses the race
3849			 * against this function.
3850			 */
3851			scsi_device_set_state(sdev, SDEV_OFFLINE);
3852		} else {
3853			WARN_ON(1);
3854			sdev = NULL;
3855		}
3856	}
3857
3858	spin_unlock_irqrestore(ap->lock, flags);
3859	mutex_unlock(&ap->scsi_host->scan_mutex);
3860
3861	if (sdev) {
3862		ata_dev_info(dev, "detaching (SCSI %s)\n",
3863			     dev_name(&sdev->sdev_gendev));
3864
3865		scsi_remove_device(sdev);
3866		scsi_device_put(sdev);
3867	}
3868}
3869
3870static void ata_scsi_handle_link_detach(struct ata_link *link)
3871{
3872	struct ata_port *ap = link->ap;
3873	struct ata_device *dev;
3874
3875	ata_for_each_dev(dev, link, ALL) {
3876		unsigned long flags;
3877
3878		if (!(dev->flags & ATA_DFLAG_DETACHED))
3879			continue;
3880
3881		spin_lock_irqsave(ap->lock, flags);
3882		dev->flags &= ~ATA_DFLAG_DETACHED;
3883		spin_unlock_irqrestore(ap->lock, flags);
3884
3885		if (zpodd_dev_enabled(dev))
3886			zpodd_exit(dev);
3887
3888		ata_scsi_remove_dev(dev);
3889	}
3890}
3891
3892/**
3893 *	ata_scsi_media_change_notify - send media change event
3894 *	@dev: Pointer to the disk device with media change event
3895 *
3896 *	Tell the block layer to send a media change notification
3897 *	event.
3898 *
3899 * 	LOCKING:
3900 * 	spin_lock_irqsave(host lock)
3901 */
3902void ata_scsi_media_change_notify(struct ata_device *dev)
3903{
3904	if (dev->sdev)
3905		sdev_evt_send_simple(dev->sdev, SDEV_EVT_MEDIA_CHANGE,
3906				     GFP_ATOMIC);
3907}
3908
3909/**
3910 *	ata_scsi_hotplug - SCSI part of hotplug
3911 *	@work: Pointer to ATA port to perform SCSI hotplug on
3912 *
3913 *	Perform SCSI part of hotplug.  It's executed from a separate
3914 *	workqueue after EH completes.  This is necessary because SCSI
3915 *	hot plugging requires working EH and hot unplugging is
3916 *	synchronized with hot plugging with a mutex.
3917 *
3918 *	LOCKING:
3919 *	Kernel thread context (may sleep).
3920 */
3921void ata_scsi_hotplug(struct work_struct *work)
3922{
3923	struct ata_port *ap =
3924		container_of(work, struct ata_port, hotplug_task.work);
3925	int i;
3926
3927	if (ap->pflags & ATA_PFLAG_UNLOADING) {
3928		DPRINTK("ENTER/EXIT - unloading\n");
3929		return;
3930	}
3931
3932	/*
3933	 * XXX - UGLY HACK
3934	 *
3935	 * The block layer suspend/resume path is fundamentally broken due
3936	 * to freezable kthreads and workqueue and may deadlock if a block
3937	 * device gets removed while resume is in progress.  I don't know
3938	 * what the solution is short of removing freezable kthreads and
3939	 * workqueues altogether.
3940	 *
3941	 * The following is an ugly hack to avoid kicking off device
3942	 * removal while freezer is active.  This is a joke but does avoid
3943	 * this particular deadlock scenario.
3944	 *
3945	 * https://bugzilla.kernel.org/show_bug.cgi?id=62801
3946	 * http://marc.info/?l=linux-kernel&m=138695698516487
3947	 */
3948#ifdef CONFIG_FREEZER
3949	while (pm_freezing)
3950		msleep(10);
3951#endif
3952
3953	DPRINTK("ENTER\n");
3954	mutex_lock(&ap->scsi_scan_mutex);
3955
3956	/* Unplug detached devices.  We cannot use link iterator here
3957	 * because PMP links have to be scanned even if PMP is
3958	 * currently not attached.  Iterate manually.
3959	 */
3960	ata_scsi_handle_link_detach(&ap->link);
3961	if (ap->pmp_link)
3962		for (i = 0; i < SATA_PMP_MAX_PORTS; i++)
3963			ata_scsi_handle_link_detach(&ap->pmp_link[i]);
3964
3965	/* scan for new ones */
3966	ata_scsi_scan_host(ap, 0);
3967
3968	mutex_unlock(&ap->scsi_scan_mutex);
3969	DPRINTK("EXIT\n");
3970}
3971
3972/**
3973 *	ata_scsi_user_scan - indication for user-initiated bus scan
3974 *	@shost: SCSI host to scan
3975 *	@channel: Channel to scan
3976 *	@id: ID to scan
3977 *	@lun: LUN to scan
3978 *
3979 *	This function is called when user explicitly requests bus
3980 *	scan.  Set probe pending flag and invoke EH.
3981 *
3982 *	LOCKING:
3983 *	SCSI layer (we don't care)
3984 *
3985 *	RETURNS:
3986 *	Zero.
3987 */
3988int ata_scsi_user_scan(struct Scsi_Host *shost, unsigned int channel,
3989		       unsigned int id, u64 lun)
3990{
3991	struct ata_port *ap = ata_shost_to_port(shost);
3992	unsigned long flags;
3993	int devno, rc = 0;
3994
3995	if (!ap->ops->error_handler)
3996		return -EOPNOTSUPP;
3997
3998	if (lun != SCAN_WILD_CARD && lun)
3999		return -EINVAL;
4000
4001	if (!sata_pmp_attached(ap)) {
4002		if (channel != SCAN_WILD_CARD && channel)
4003			return -EINVAL;
4004		devno = id;
4005	} else {
4006		if (id != SCAN_WILD_CARD && id)
4007			return -EINVAL;
4008		devno = channel;
4009	}
4010
4011	spin_lock_irqsave(ap->lock, flags);
4012
4013	if (devno == SCAN_WILD_CARD) {
4014		struct ata_link *link;
4015
4016		ata_for_each_link(link, ap, EDGE) {
4017			struct ata_eh_info *ehi = &link->eh_info;
4018			ehi->probe_mask |= ATA_ALL_DEVICES;
4019			ehi->action |= ATA_EH_RESET;
4020		}
4021	} else {
4022		struct ata_device *dev = ata_find_dev(ap, devno);
4023
4024		if (dev) {
4025			struct ata_eh_info *ehi = &dev->link->eh_info;
4026			ehi->probe_mask |= 1 << dev->devno;
4027			ehi->action |= ATA_EH_RESET;
4028		} else
4029			rc = -EINVAL;
4030	}
4031
4032	if (rc == 0) {
4033		ata_port_schedule_eh(ap);
4034		spin_unlock_irqrestore(ap->lock, flags);
4035		ata_port_wait_eh(ap);
4036	} else
4037		spin_unlock_irqrestore(ap->lock, flags);
4038
4039	return rc;
4040}
4041
4042/**
4043 *	ata_scsi_dev_rescan - initiate scsi_rescan_device()
4044 *	@work: Pointer to ATA port to perform scsi_rescan_device()
4045 *
4046 *	After ATA pass thru (SAT) commands are executed successfully,
4047 *	libata need to propagate the changes to SCSI layer.
4048 *
4049 *	LOCKING:
4050 *	Kernel thread context (may sleep).
4051 */
4052void ata_scsi_dev_rescan(struct work_struct *work)
4053{
4054	struct ata_port *ap =
4055		container_of(work, struct ata_port, scsi_rescan_task);
4056	struct ata_link *link;
4057	struct ata_device *dev;
4058	unsigned long flags;
4059
4060	mutex_lock(&ap->scsi_scan_mutex);
4061	spin_lock_irqsave(ap->lock, flags);
4062
4063	ata_for_each_link(link, ap, EDGE) {
4064		ata_for_each_dev(dev, link, ENABLED) {
4065			struct scsi_device *sdev = dev->sdev;
4066
4067			if (!sdev)
4068				continue;
4069			if (scsi_device_get(sdev))
4070				continue;
4071
4072			spin_unlock_irqrestore(ap->lock, flags);
4073			scsi_rescan_device(&(sdev->sdev_gendev));
4074			scsi_device_put(sdev);
4075			spin_lock_irqsave(ap->lock, flags);
4076		}
4077	}
4078
4079	spin_unlock_irqrestore(ap->lock, flags);
4080	mutex_unlock(&ap->scsi_scan_mutex);
4081}
4082
4083/**
4084 *	ata_sas_port_alloc - Allocate port for a SAS attached SATA device
4085 *	@host: ATA host container for all SAS ports
4086 *	@port_info: Information from low-level host driver
4087 *	@shost: SCSI host that the scsi device is attached to
4088 *
4089 *	LOCKING:
4090 *	PCI/etc. bus probe sem.
4091 *
4092 *	RETURNS:
4093 *	ata_port pointer on success / NULL on failure.
4094 */
4095
4096struct ata_port *ata_sas_port_alloc(struct ata_host *host,
4097				    struct ata_port_info *port_info,
4098				    struct Scsi_Host *shost)
4099{
4100	struct ata_port *ap;
4101
4102	ap = ata_port_alloc(host);
4103	if (!ap)
4104		return NULL;
4105
4106	ap->port_no = 0;
4107	ap->lock = &host->lock;
4108	ap->pio_mask = port_info->pio_mask;
4109	ap->mwdma_mask = port_info->mwdma_mask;
4110	ap->udma_mask = port_info->udma_mask;
4111	ap->flags |= port_info->flags;
4112	ap->ops = port_info->port_ops;
4113	ap->cbl = ATA_CBL_SATA;
4114
4115	return ap;
4116}
4117EXPORT_SYMBOL_GPL(ata_sas_port_alloc);
4118
4119/**
4120 *	ata_sas_port_start - Set port up for dma.
4121 *	@ap: Port to initialize
4122 *
4123 *	Called just after data structures for each port are
4124 *	initialized.
4125 *
4126 *	May be used as the port_start() entry in ata_port_operations.
4127 *
4128 *	LOCKING:
4129 *	Inherited from caller.
4130 */
4131int ata_sas_port_start(struct ata_port *ap)
4132{
4133	/*
4134	 * the port is marked as frozen at allocation time, but if we don't
4135	 * have new eh, we won't thaw it
4136	 */
4137	if (!ap->ops->error_handler)
4138		ap->pflags &= ~ATA_PFLAG_FROZEN;
4139	return 0;
4140}
4141EXPORT_SYMBOL_GPL(ata_sas_port_start);
4142
4143/**
4144 *	ata_port_stop - Undo ata_sas_port_start()
4145 *	@ap: Port to shut down
4146 *
4147 *	May be used as the port_stop() entry in ata_port_operations.
4148 *
4149 *	LOCKING:
4150 *	Inherited from caller.
4151 */
4152
4153void ata_sas_port_stop(struct ata_port *ap)
4154{
4155}
4156EXPORT_SYMBOL_GPL(ata_sas_port_stop);
4157
4158/**
4159 * ata_sas_async_probe - simply schedule probing and return
4160 * @ap: Port to probe
4161 *
4162 * For batch scheduling of probe for sas attached ata devices, assumes
4163 * the port has already been through ata_sas_port_init()
4164 */
4165void ata_sas_async_probe(struct ata_port *ap)
4166{
4167	__ata_port_probe(ap);
4168}
4169EXPORT_SYMBOL_GPL(ata_sas_async_probe);
4170
4171int ata_sas_sync_probe(struct ata_port *ap)
4172{
4173	return ata_port_probe(ap);
4174}
4175EXPORT_SYMBOL_GPL(ata_sas_sync_probe);
4176
4177
4178/**
4179 *	ata_sas_port_init - Initialize a SATA device
4180 *	@ap: SATA port to initialize
4181 *
4182 *	LOCKING:
4183 *	PCI/etc. bus probe sem.
4184 *
4185 *	RETURNS:
4186 *	Zero on success, non-zero on error.
4187 */
4188
4189int ata_sas_port_init(struct ata_port *ap)
4190{
4191	int rc = ap->ops->port_start(ap);
4192
4193	if (rc)
4194		return rc;
4195	ap->print_id = atomic_inc_return(&ata_print_id);
4196	return 0;
4197}
4198EXPORT_SYMBOL_GPL(ata_sas_port_init);
4199
4200/**
4201 *	ata_sas_port_destroy - Destroy a SATA port allocated by ata_sas_port_alloc
4202 *	@ap: SATA port to destroy
4203 *
4204 */
4205
4206void ata_sas_port_destroy(struct ata_port *ap)
4207{
4208	if (ap->ops->port_stop)
4209		ap->ops->port_stop(ap);
4210	kfree(ap);
4211}
4212EXPORT_SYMBOL_GPL(ata_sas_port_destroy);
4213
4214/**
4215 *	ata_sas_slave_configure - Default slave_config routine for libata devices
4216 *	@sdev: SCSI device to configure
4217 *	@ap: ATA port to which SCSI device is attached
4218 *
4219 *	RETURNS:
4220 *	Zero.
4221 */
4222
4223int ata_sas_slave_configure(struct scsi_device *sdev, struct ata_port *ap)
4224{
4225	ata_scsi_sdev_config(sdev);
4226	ata_scsi_dev_config(sdev, ap->link.device);
4227	return 0;
4228}
4229EXPORT_SYMBOL_GPL(ata_sas_slave_configure);
4230
4231/**
4232 *	ata_sas_queuecmd - Issue SCSI cdb to libata-managed device
4233 *	@cmd: SCSI command to be sent
4234 *	@ap:	ATA port to which the command is being sent
4235 *
4236 *	RETURNS:
4237 *	Return value from __ata_scsi_queuecmd() if @cmd can be queued,
4238 *	0 otherwise.
4239 */
4240
4241int ata_sas_queuecmd(struct scsi_cmnd *cmd, struct ata_port *ap)
4242{
4243	int rc = 0;
4244
4245	ata_scsi_dump_cdb(ap, cmd);
4246
4247	if (likely(ata_dev_enabled(ap->link.device)))
4248		rc = __ata_scsi_queuecmd(cmd, ap->link.device);
4249	else {
4250		cmd->result = (DID_BAD_TARGET << 16);
4251		cmd->scsi_done(cmd);
4252	}
4253	return rc;
4254}
4255EXPORT_SYMBOL_GPL(ata_sas_queuecmd);
4256
4257int ata_sas_allocate_tag(struct ata_port *ap)
4258{
4259	unsigned int max_queue = ap->host->n_tags;
4260	unsigned int i, tag;
4261
4262	for (i = 0, tag = ap->sas_last_tag + 1; i < max_queue; i++, tag++) {
4263		tag = tag < max_queue ? tag : 0;
4264
4265		/* the last tag is reserved for internal command. */
4266		if (tag == ATA_TAG_INTERNAL)
4267			continue;
4268
4269		if (!test_and_set_bit(tag, &ap->sas_tag_allocated)) {
4270			ap->sas_last_tag = tag;
4271			return tag;
4272		}
4273	}
4274	return -1;
4275}
4276
4277void ata_sas_free_tag(unsigned int tag, struct ata_port *ap)
4278{
4279	clear_bit(tag, &ap->sas_tag_allocated);
4280}
4281