xref: /openbmc/linux/drivers/ata/libata-scsi.c (revision 6f366c1c751454df3d1c0f25f15ee0164821112a)
1 /*
2  *  libata-scsi.c - helper library for ATA
3  *
4  *  Maintained by:  Jeff Garzik <jgarzik@pobox.com>
5  *    		    Please ALWAYS copy linux-ide@vger.kernel.org
6  *		    on emails.
7  *
8  *  Copyright 2003-2004 Red Hat, Inc.  All rights reserved.
9  *  Copyright 2003-2004 Jeff Garzik
10  *
11  *
12  *  This program is free software; you can redistribute it and/or modify
13  *  it under the terms of the GNU General Public License as published by
14  *  the Free Software Foundation; either version 2, or (at your option)
15  *  any later version.
16  *
17  *  This program is distributed in the hope that it will be useful,
18  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
19  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
20  *  GNU General Public License for more details.
21  *
22  *  You should have received a copy of the GNU General Public License
23  *  along with this program; see the file COPYING.  If not, write to
24  *  the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
25  *
26  *
27  *  libata documentation is available via 'make {ps|pdf}docs',
28  *  as Documentation/DocBook/libata.*
29  *
30  *  Hardware documentation available from
31  *  - http://www.t10.org/
32  *  - http://www.t13.org/
33  *
34  */
35 
36 #include <linux/kernel.h>
37 #include <linux/blkdev.h>
38 #include <linux/spinlock.h>
39 #include <scsi/scsi.h>
40 #include <scsi/scsi_host.h>
41 #include <scsi/scsi_cmnd.h>
42 #include <scsi/scsi_eh.h>
43 #include <scsi/scsi_device.h>
44 #include <scsi/scsi_tcq.h>
45 #include <scsi/scsi_transport.h>
46 #include <linux/libata.h>
47 #include <linux/hdreg.h>
48 #include <asm/uaccess.h>
49 
50 #include "libata.h"
51 
52 #define SECTOR_SIZE	512
53 
54 typedef unsigned int (*ata_xlat_func_t)(struct ata_queued_cmd *qc);
55 
56 static struct ata_device * __ata_scsi_find_dev(struct ata_port *ap,
57 					const struct scsi_device *scsidev);
58 static struct ata_device * ata_scsi_find_dev(struct ata_port *ap,
59 					    const struct scsi_device *scsidev);
60 static int ata_scsi_user_scan(struct Scsi_Host *shost, unsigned int channel,
61 			      unsigned int id, unsigned int lun);
62 
63 
64 #define RW_RECOVERY_MPAGE 0x1
65 #define RW_RECOVERY_MPAGE_LEN 12
66 #define CACHE_MPAGE 0x8
67 #define CACHE_MPAGE_LEN 20
68 #define CONTROL_MPAGE 0xa
69 #define CONTROL_MPAGE_LEN 12
70 #define ALL_MPAGES 0x3f
71 #define ALL_SUB_MPAGES 0xff
72 
73 
74 static const u8 def_rw_recovery_mpage[] = {
75 	RW_RECOVERY_MPAGE,
76 	RW_RECOVERY_MPAGE_LEN - 2,
77 	(1 << 7) |	/* AWRE, sat-r06 say it shall be 0 */
78 	    (1 << 6),	/* ARRE (auto read reallocation) */
79 	0,		/* read retry count */
80 	0, 0, 0, 0,
81 	0,		/* write retry count */
82 	0, 0, 0
83 };
84 
85 static const u8 def_cache_mpage[CACHE_MPAGE_LEN] = {
86 	CACHE_MPAGE,
87 	CACHE_MPAGE_LEN - 2,
88 	0,		/* contains WCE, needs to be 0 for logic */
89 	0, 0, 0, 0, 0, 0, 0, 0, 0,
90 	0,		/* contains DRA, needs to be 0 for logic */
91 	0, 0, 0, 0, 0, 0, 0
92 };
93 
94 static const u8 def_control_mpage[CONTROL_MPAGE_LEN] = {
95 	CONTROL_MPAGE,
96 	CONTROL_MPAGE_LEN - 2,
97 	2,	/* DSENSE=0, GLTSD=1 */
98 	0,	/* [QAM+QERR may be 1, see 05-359r1] */
99 	0, 0, 0, 0, 0xff, 0xff,
100 	0, 30	/* extended self test time, see 05-359r1 */
101 };
102 
103 /*
104  * libata transport template.  libata doesn't do real transport stuff.
105  * It just needs the eh_timed_out hook.
106  */
107 struct scsi_transport_template ata_scsi_transport_template = {
108 	.eh_strategy_handler	= ata_scsi_error,
109 	.eh_timed_out		= ata_scsi_timed_out,
110 	.user_scan		= ata_scsi_user_scan,
111 };
112 
113 
114 static void ata_scsi_invalid_field(struct scsi_cmnd *cmd,
115 				   void (*done)(struct scsi_cmnd *))
116 {
117 	ata_scsi_set_sense(cmd, ILLEGAL_REQUEST, 0x24, 0x0);
118 	/* "Invalid field in cbd" */
119 	done(cmd);
120 }
121 
122 /**
123  *	ata_std_bios_param - generic bios head/sector/cylinder calculator used by sd.
124  *	@sdev: SCSI device for which BIOS geometry is to be determined
125  *	@bdev: block device associated with @sdev
126  *	@capacity: capacity of SCSI device
127  *	@geom: location to which geometry will be output
128  *
129  *	Generic bios head/sector/cylinder calculator
130  *	used by sd. Most BIOSes nowadays expect a XXX/255/16  (CHS)
131  *	mapping. Some situations may arise where the disk is not
132  *	bootable if this is not used.
133  *
134  *	LOCKING:
135  *	Defined by the SCSI layer.  We don't really care.
136  *
137  *	RETURNS:
138  *	Zero.
139  */
140 int ata_std_bios_param(struct scsi_device *sdev, struct block_device *bdev,
141 		       sector_t capacity, int geom[])
142 {
143 	geom[0] = 255;
144 	geom[1] = 63;
145 	sector_div(capacity, 255*63);
146 	geom[2] = capacity;
147 
148 	return 0;
149 }
150 
151 /**
152  *	ata_get_identity - Handler for HDIO_GET_IDENTITY ioctl
153  *	@sdev: SCSI device to get identify data for
154  *	@arg: User buffer area for identify data
155  *
156  *	LOCKING:
157  *	Defined by the SCSI layer.  We don't really care.
158  *
159  *	RETURNS:
160  *	Zero on success, negative errno on error.
161  */
162 static int ata_get_identity(struct scsi_device *sdev, void __user *arg)
163 {
164 	struct ata_port *ap = ata_shost_to_port(sdev->host);
165 	struct ata_device *dev = ata_scsi_find_dev(ap, sdev);
166 	u16 __user *dst = arg;
167 	char buf[40];
168 
169 	if (!dev)
170 		return -ENOMSG;
171 
172 	if (copy_to_user(dst, dev->id, ATA_ID_WORDS * sizeof(u16)))
173 		return -EFAULT;
174 
175 	ata_id_string(dev->id, buf, ATA_ID_PROD, ATA_ID_PROD_LEN);
176 	if (copy_to_user(dst + ATA_ID_PROD, buf, ATA_ID_PROD_LEN))
177 		return -EFAULT;
178 
179 	ata_id_string(dev->id, buf, ATA_ID_FW_REV, ATA_ID_FW_REV_LEN);
180 	if (copy_to_user(dst + ATA_ID_FW_REV, buf, ATA_ID_FW_REV_LEN))
181 		return -EFAULT;
182 
183 	ata_id_string(dev->id, buf, ATA_ID_SERNO, ATA_ID_SERNO_LEN);
184 	if (copy_to_user(dst + ATA_ID_SERNO, buf, ATA_ID_SERNO_LEN))
185 		return -EFAULT;
186 
187 	return 0;
188 }
189 
190 /**
191  *	ata_cmd_ioctl - Handler for HDIO_DRIVE_CMD ioctl
192  *	@scsidev: Device to which we are issuing command
193  *	@arg: User provided data for issuing command
194  *
195  *	LOCKING:
196  *	Defined by the SCSI layer.  We don't really care.
197  *
198  *	RETURNS:
199  *	Zero on success, negative errno on error.
200  */
201 int ata_cmd_ioctl(struct scsi_device *scsidev, void __user *arg)
202 {
203 	int rc = 0;
204 	u8 scsi_cmd[MAX_COMMAND_SIZE];
205 	u8 args[4], *argbuf = NULL, *sensebuf = NULL;
206 	int argsize = 0;
207 	enum dma_data_direction data_dir;
208 	int cmd_result;
209 
210 	if (arg == NULL)
211 		return -EINVAL;
212 
213 	if (copy_from_user(args, arg, sizeof(args)))
214 		return -EFAULT;
215 
216 	sensebuf = kzalloc(SCSI_SENSE_BUFFERSIZE, GFP_NOIO);
217 	if (!sensebuf)
218 		return -ENOMEM;
219 
220 	memset(scsi_cmd, 0, sizeof(scsi_cmd));
221 
222 	if (args[3]) {
223 		argsize = SECTOR_SIZE * args[3];
224 		argbuf = kmalloc(argsize, GFP_KERNEL);
225 		if (argbuf == NULL) {
226 			rc = -ENOMEM;
227 			goto error;
228 		}
229 
230 		scsi_cmd[1]  = (4 << 1); /* PIO Data-in */
231 		scsi_cmd[2]  = 0x0e;     /* no off.line or cc, read from dev,
232 		                            block count in sector count field */
233 		data_dir = DMA_FROM_DEVICE;
234 	} else {
235 		scsi_cmd[1]  = (3 << 1); /* Non-data */
236 		scsi_cmd[2]  = 0x20;     /* cc but no off.line or data xfer */
237 		data_dir = DMA_NONE;
238 	}
239 
240 	scsi_cmd[0] = ATA_16;
241 
242 	scsi_cmd[4] = args[2];
243 	if (args[0] == WIN_SMART) { /* hack -- ide driver does this too... */
244 		scsi_cmd[6]  = args[3];
245 		scsi_cmd[8]  = args[1];
246 		scsi_cmd[10] = 0x4f;
247 		scsi_cmd[12] = 0xc2;
248 	} else {
249 		scsi_cmd[6]  = args[1];
250 	}
251 	scsi_cmd[14] = args[0];
252 
253 	/* Good values for timeout and retries?  Values below
254 	   from scsi_ioctl_send_command() for default case... */
255 	cmd_result = scsi_execute(scsidev, scsi_cmd, data_dir, argbuf, argsize,
256 	                          sensebuf, (10*HZ), 5, 0);
257 
258 	if (driver_byte(cmd_result) == DRIVER_SENSE) {/* sense data available */
259 		u8 *desc = sensebuf + 8;
260 		cmd_result &= ~(0xFF<<24); /* DRIVER_SENSE is not an error */
261 
262 		/* If we set cc then ATA pass-through will cause a
263 		 * check condition even if no error. Filter that. */
264 		if (cmd_result & SAM_STAT_CHECK_CONDITION) {
265 			struct scsi_sense_hdr sshdr;
266 			scsi_normalize_sense(sensebuf, SCSI_SENSE_BUFFERSIZE,
267 			                      &sshdr);
268 			if (sshdr.sense_key==0 &&
269 			    sshdr.asc==0 && sshdr.ascq==0)
270 				cmd_result &= ~SAM_STAT_CHECK_CONDITION;
271 		}
272 
273 		/* Send userspace a few ATA registers (same as drivers/ide) */
274 		if (sensebuf[0] == 0x72 &&     /* format is "descriptor" */
275 		    desc[0] == 0x09 ) {        /* code is "ATA Descriptor" */
276 			args[0] = desc[13];    /* status */
277 			args[1] = desc[3];     /* error */
278 			args[2] = desc[5];     /* sector count (0:7) */
279 			if (copy_to_user(arg, args, sizeof(args)))
280 				rc = -EFAULT;
281 		}
282 	}
283 
284 
285 	if (cmd_result) {
286 		rc = -EIO;
287 		goto error;
288 	}
289 
290 	if ((argbuf)
291 	 && copy_to_user(arg + sizeof(args), argbuf, argsize))
292 		rc = -EFAULT;
293 error:
294 	kfree(sensebuf);
295 	kfree(argbuf);
296 	return rc;
297 }
298 
299 /**
300  *	ata_task_ioctl - Handler for HDIO_DRIVE_TASK ioctl
301  *	@scsidev: Device to which we are issuing command
302  *	@arg: User provided data for issuing command
303  *
304  *	LOCKING:
305  *	Defined by the SCSI layer.  We don't really care.
306  *
307  *	RETURNS:
308  *	Zero on success, negative errno on error.
309  */
310 int ata_task_ioctl(struct scsi_device *scsidev, void __user *arg)
311 {
312 	int rc = 0;
313 	u8 scsi_cmd[MAX_COMMAND_SIZE];
314 	u8 args[7], *sensebuf = NULL;
315 	int cmd_result;
316 
317 	if (arg == NULL)
318 		return -EINVAL;
319 
320 	if (copy_from_user(args, arg, sizeof(args)))
321 		return -EFAULT;
322 
323 	sensebuf = kzalloc(SCSI_SENSE_BUFFERSIZE, GFP_NOIO);
324 	if (!sensebuf)
325 		return -ENOMEM;
326 
327 	memset(scsi_cmd, 0, sizeof(scsi_cmd));
328 	scsi_cmd[0]  = ATA_16;
329 	scsi_cmd[1]  = (3 << 1); /* Non-data */
330 	scsi_cmd[2]  = 0x20;     /* cc but no off.line or data xfer */
331 	scsi_cmd[4]  = args[1];
332 	scsi_cmd[6]  = args[2];
333 	scsi_cmd[8]  = args[3];
334 	scsi_cmd[10] = args[4];
335 	scsi_cmd[12] = args[5];
336 	scsi_cmd[13] = args[6] & 0x0f;
337 	scsi_cmd[14] = args[0];
338 
339 	/* Good values for timeout and retries?  Values below
340 	   from scsi_ioctl_send_command() for default case... */
341 	cmd_result = scsi_execute(scsidev, scsi_cmd, DMA_NONE, NULL, 0,
342 				sensebuf, (10*HZ), 5, 0);
343 
344 	if (driver_byte(cmd_result) == DRIVER_SENSE) {/* sense data available */
345 		u8 *desc = sensebuf + 8;
346 		cmd_result &= ~(0xFF<<24); /* DRIVER_SENSE is not an error */
347 
348 		/* If we set cc then ATA pass-through will cause a
349 		 * check condition even if no error. Filter that. */
350 		if (cmd_result & SAM_STAT_CHECK_CONDITION) {
351 			struct scsi_sense_hdr sshdr;
352 			scsi_normalize_sense(sensebuf, SCSI_SENSE_BUFFERSIZE,
353 						&sshdr);
354 			if (sshdr.sense_key==0 &&
355 				sshdr.asc==0 && sshdr.ascq==0)
356 				cmd_result &= ~SAM_STAT_CHECK_CONDITION;
357 		}
358 
359 		/* Send userspace ATA registers */
360 		if (sensebuf[0] == 0x72 &&	/* format is "descriptor" */
361 				desc[0] == 0x09) {/* code is "ATA Descriptor" */
362 			args[0] = desc[13];	/* status */
363 			args[1] = desc[3];	/* error */
364 			args[2] = desc[5];	/* sector count (0:7) */
365 			args[3] = desc[7];	/* lbal */
366 			args[4] = desc[9];	/* lbam */
367 			args[5] = desc[11];	/* lbah */
368 			args[6] = desc[12];	/* select */
369 			if (copy_to_user(arg, args, sizeof(args)))
370 				rc = -EFAULT;
371 		}
372 	}
373 
374 	if (cmd_result) {
375 		rc = -EIO;
376 		goto error;
377 	}
378 
379  error:
380 	kfree(sensebuf);
381 	return rc;
382 }
383 
384 int ata_scsi_ioctl(struct scsi_device *scsidev, int cmd, void __user *arg)
385 {
386 	int val = -EINVAL, rc = -EINVAL;
387 
388 	switch (cmd) {
389 	case ATA_IOC_GET_IO32:
390 		val = 0;
391 		if (copy_to_user(arg, &val, 1))
392 			return -EFAULT;
393 		return 0;
394 
395 	case ATA_IOC_SET_IO32:
396 		val = (unsigned long) arg;
397 		if (val != 0)
398 			return -EINVAL;
399 		return 0;
400 
401 	case HDIO_GET_IDENTITY:
402 		return ata_get_identity(scsidev, arg);
403 
404 	case HDIO_DRIVE_CMD:
405 		if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
406 			return -EACCES;
407 		return ata_cmd_ioctl(scsidev, arg);
408 
409 	case HDIO_DRIVE_TASK:
410 		if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
411 			return -EACCES;
412 		return ata_task_ioctl(scsidev, arg);
413 
414 	default:
415 		rc = -ENOTTY;
416 		break;
417 	}
418 
419 	return rc;
420 }
421 
422 /**
423  *	ata_scsi_qc_new - acquire new ata_queued_cmd reference
424  *	@dev: ATA device to which the new command is attached
425  *	@cmd: SCSI command that originated this ATA command
426  *	@done: SCSI command completion function
427  *
428  *	Obtain a reference to an unused ata_queued_cmd structure,
429  *	which is the basic libata structure representing a single
430  *	ATA command sent to the hardware.
431  *
432  *	If a command was available, fill in the SCSI-specific
433  *	portions of the structure with information on the
434  *	current command.
435  *
436  *	LOCKING:
437  *	spin_lock_irqsave(host lock)
438  *
439  *	RETURNS:
440  *	Command allocated, or %NULL if none available.
441  */
442 static struct ata_queued_cmd *ata_scsi_qc_new(struct ata_device *dev,
443 					      struct scsi_cmnd *cmd,
444 					      void (*done)(struct scsi_cmnd *))
445 {
446 	struct ata_queued_cmd *qc;
447 
448 	qc = ata_qc_new_init(dev);
449 	if (qc) {
450 		qc->scsicmd = cmd;
451 		qc->scsidone = done;
452 
453 		if (cmd->use_sg) {
454 			qc->__sg = (struct scatterlist *) cmd->request_buffer;
455 			qc->n_elem = cmd->use_sg;
456 		} else if (cmd->request_bufflen) {
457 			qc->__sg = &qc->sgent;
458 			qc->n_elem = 1;
459 		}
460 	} else {
461 		cmd->result = (DID_OK << 16) | (QUEUE_FULL << 1);
462 		done(cmd);
463 	}
464 
465 	return qc;
466 }
467 
468 /**
469  *	ata_dump_status - user friendly display of error info
470  *	@id: id of the port in question
471  *	@tf: ptr to filled out taskfile
472  *
473  *	Decode and dump the ATA error/status registers for the user so
474  *	that they have some idea what really happened at the non
475  *	make-believe layer.
476  *
477  *	LOCKING:
478  *	inherited from caller
479  */
480 static void ata_dump_status(unsigned id, struct ata_taskfile *tf)
481 {
482 	u8 stat = tf->command, err = tf->feature;
483 
484 	printk(KERN_WARNING "ata%u: status=0x%02x { ", id, stat);
485 	if (stat & ATA_BUSY) {
486 		printk("Busy }\n");	/* Data is not valid in this case */
487 	} else {
488 		if (stat & 0x40)	printk("DriveReady ");
489 		if (stat & 0x20)	printk("DeviceFault ");
490 		if (stat & 0x10)	printk("SeekComplete ");
491 		if (stat & 0x08)	printk("DataRequest ");
492 		if (stat & 0x04)	printk("CorrectedError ");
493 		if (stat & 0x02)	printk("Index ");
494 		if (stat & 0x01)	printk("Error ");
495 		printk("}\n");
496 
497 		if (err) {
498 			printk(KERN_WARNING "ata%u: error=0x%02x { ", id, err);
499 			if (err & 0x04)		printk("DriveStatusError ");
500 			if (err & 0x80) {
501 				if (err & 0x04)	printk("BadCRC ");
502 				else		printk("Sector ");
503 			}
504 			if (err & 0x40)		printk("UncorrectableError ");
505 			if (err & 0x10)		printk("SectorIdNotFound ");
506 			if (err & 0x02)		printk("TrackZeroNotFound ");
507 			if (err & 0x01)		printk("AddrMarkNotFound ");
508 			printk("}\n");
509 		}
510 	}
511 }
512 
513 /**
514  *	ata_scsi_device_suspend - suspend ATA device associated with sdev
515  *	@sdev: the SCSI device to suspend
516  *	@mesg: target power management message
517  *
518  *	Request suspend EH action on the ATA device associated with
519  *	@sdev and wait for the operation to complete.
520  *
521  *	LOCKING:
522  *	Kernel thread context (may sleep).
523  *
524  *	RETURNS:
525  *	0 on success, -errno otherwise.
526  */
527 int ata_scsi_device_suspend(struct scsi_device *sdev, pm_message_t mesg)
528 {
529 	struct ata_port *ap = ata_shost_to_port(sdev->host);
530 	struct ata_device *dev = ata_scsi_find_dev(ap, sdev);
531 	unsigned long flags;
532 	unsigned int action;
533 	int rc = 0;
534 
535 	if (!dev)
536 		goto out;
537 
538 	spin_lock_irqsave(ap->lock, flags);
539 
540 	/* wait for the previous resume to complete */
541 	while (dev->flags & ATA_DFLAG_SUSPENDED) {
542 		spin_unlock_irqrestore(ap->lock, flags);
543 		ata_port_wait_eh(ap);
544 		spin_lock_irqsave(ap->lock, flags);
545 	}
546 
547 	/* if @sdev is already detached, nothing to do */
548 	if (sdev->sdev_state == SDEV_OFFLINE ||
549 	    sdev->sdev_state == SDEV_CANCEL || sdev->sdev_state == SDEV_DEL)
550 		goto out_unlock;
551 
552 	/* request suspend */
553 	action = ATA_EH_SUSPEND;
554 	if (mesg.event != PM_EVENT_SUSPEND)
555 		action |= ATA_EH_PM_FREEZE;
556 	ap->eh_info.dev_action[dev->devno] |= action;
557 	ap->eh_info.flags |= ATA_EHI_QUIET;
558 	ata_port_schedule_eh(ap);
559 
560 	spin_unlock_irqrestore(ap->lock, flags);
561 
562 	/* wait for EH to do the job */
563 	ata_port_wait_eh(ap);
564 
565 	spin_lock_irqsave(ap->lock, flags);
566 
567 	/* If @sdev is still attached but the associated ATA device
568 	 * isn't suspended, the operation failed.
569 	 */
570 	if (sdev->sdev_state != SDEV_OFFLINE &&
571 	    sdev->sdev_state != SDEV_CANCEL && sdev->sdev_state != SDEV_DEL &&
572 	    !(dev->flags & ATA_DFLAG_SUSPENDED))
573 		rc = -EIO;
574 
575  out_unlock:
576 	spin_unlock_irqrestore(ap->lock, flags);
577  out:
578 	if (rc == 0)
579 		sdev->sdev_gendev.power.power_state = mesg;
580 	return rc;
581 }
582 
583 /**
584  *	ata_scsi_device_resume - resume ATA device associated with sdev
585  *	@sdev: the SCSI device to resume
586  *
587  *	Request resume EH action on the ATA device associated with
588  *	@sdev and return immediately.  This enables parallel
589  *	wakeup/spinup of devices.
590  *
591  *	LOCKING:
592  *	Kernel thread context (may sleep).
593  *
594  *	RETURNS:
595  *	0.
596  */
597 int ata_scsi_device_resume(struct scsi_device *sdev)
598 {
599 	struct ata_port *ap = ata_shost_to_port(sdev->host);
600 	struct ata_device *dev = ata_scsi_find_dev(ap, sdev);
601 	struct ata_eh_info *ehi = &ap->eh_info;
602 	unsigned long flags;
603 	unsigned int action;
604 
605 	if (!dev)
606 		goto out;
607 
608 	spin_lock_irqsave(ap->lock, flags);
609 
610 	/* if @sdev is already detached, nothing to do */
611 	if (sdev->sdev_state == SDEV_OFFLINE ||
612 	    sdev->sdev_state == SDEV_CANCEL || sdev->sdev_state == SDEV_DEL)
613 		goto out_unlock;
614 
615 	/* request resume */
616 	action = ATA_EH_RESUME;
617 	if (sdev->sdev_gendev.power.power_state.event == PM_EVENT_SUSPEND)
618 		__ata_ehi_hotplugged(ehi);
619 	else
620 		action |= ATA_EH_PM_FREEZE | ATA_EH_SOFTRESET;
621 	ehi->dev_action[dev->devno] |= action;
622 
623 	/* We don't want autopsy and verbose EH messages.  Disable
624 	 * those if we're the only device on this link.
625 	 */
626 	if (ata_port_max_devices(ap) == 1)
627 		ehi->flags |= ATA_EHI_NO_AUTOPSY | ATA_EHI_QUIET;
628 
629 	ata_port_schedule_eh(ap);
630 
631  out_unlock:
632 	spin_unlock_irqrestore(ap->lock, flags);
633  out:
634 	sdev->sdev_gendev.power.power_state = PMSG_ON;
635 	return 0;
636 }
637 
638 /**
639  *	ata_to_sense_error - convert ATA error to SCSI error
640  *	@id: ATA device number
641  *	@drv_stat: value contained in ATA status register
642  *	@drv_err: value contained in ATA error register
643  *	@sk: the sense key we'll fill out
644  *	@asc: the additional sense code we'll fill out
645  *	@ascq: the additional sense code qualifier we'll fill out
646  *	@verbose: be verbose
647  *
648  *	Converts an ATA error into a SCSI error.  Fill out pointers to
649  *	SK, ASC, and ASCQ bytes for later use in fixed or descriptor
650  *	format sense blocks.
651  *
652  *	LOCKING:
653  *	spin_lock_irqsave(host lock)
654  */
655 static void ata_to_sense_error(unsigned id, u8 drv_stat, u8 drv_err, u8 *sk,
656 			       u8 *asc, u8 *ascq, int verbose)
657 {
658 	int i;
659 
660 	/* Based on the 3ware driver translation table */
661 	static const unsigned char sense_table[][4] = {
662 		/* BBD|ECC|ID|MAR */
663 		{0xd1, 		ABORTED_COMMAND, 0x00, 0x00}, 	// Device busy                  Aborted command
664 		/* BBD|ECC|ID */
665 		{0xd0,  	ABORTED_COMMAND, 0x00, 0x00}, 	// Device busy                  Aborted command
666 		/* ECC|MC|MARK */
667 		{0x61, 		HARDWARE_ERROR, 0x00, 0x00}, 	// Device fault                 Hardware error
668 		/* ICRC|ABRT */		/* NB: ICRC & !ABRT is BBD */
669 		{0x84, 		ABORTED_COMMAND, 0x47, 0x00}, 	// Data CRC error               SCSI parity error
670 		/* MC|ID|ABRT|TRK0|MARK */
671 		{0x37, 		NOT_READY, 0x04, 0x00}, 	// Unit offline                 Not ready
672 		/* MCR|MARK */
673 		{0x09, 		NOT_READY, 0x04, 0x00}, 	// Unrecovered disk error       Not ready
674 		/*  Bad address mark */
675 		{0x01, 		MEDIUM_ERROR, 0x13, 0x00}, 	// Address mark not found       Address mark not found for data field
676 		/* TRK0 */
677 		{0x02, 		HARDWARE_ERROR, 0x00, 0x00}, 	// Track 0 not found		  Hardware error
678 		/* Abort & !ICRC */
679 		{0x04, 		ABORTED_COMMAND, 0x00, 0x00}, 	// Aborted command              Aborted command
680 		/* Media change request */
681 		{0x08, 		NOT_READY, 0x04, 0x00}, 	// Media change request	  FIXME: faking offline
682 		/* SRV */
683 		{0x10, 		ABORTED_COMMAND, 0x14, 0x00}, 	// ID not found                 Recorded entity not found
684 		/* Media change */
685 		{0x08,  	NOT_READY, 0x04, 0x00}, 	// Media change		  FIXME: faking offline
686 		/* ECC */
687 		{0x40, 		MEDIUM_ERROR, 0x11, 0x04}, 	// Uncorrectable ECC error      Unrecovered read error
688 		/* BBD - block marked bad */
689 		{0x80, 		MEDIUM_ERROR, 0x11, 0x04}, 	// Block marked bad		  Medium error, unrecovered read error
690 		{0xFF, 0xFF, 0xFF, 0xFF}, // END mark
691 	};
692 	static const unsigned char stat_table[][4] = {
693 		/* Must be first because BUSY means no other bits valid */
694 		{0x80, 		ABORTED_COMMAND, 0x47, 0x00},	// Busy, fake parity for now
695 		{0x20, 		HARDWARE_ERROR,  0x00, 0x00}, 	// Device fault
696 		{0x08, 		ABORTED_COMMAND, 0x47, 0x00},	// Timed out in xfer, fake parity for now
697 		{0x04, 		RECOVERED_ERROR, 0x11, 0x00},	// Recovered ECC error	  Medium error, recovered
698 		{0xFF, 0xFF, 0xFF, 0xFF}, // END mark
699 	};
700 
701 	/*
702 	 *	Is this an error we can process/parse
703 	 */
704 	if (drv_stat & ATA_BUSY) {
705 		drv_err = 0;	/* Ignore the err bits, they're invalid */
706 	}
707 
708 	if (drv_err) {
709 		/* Look for drv_err */
710 		for (i = 0; sense_table[i][0] != 0xFF; i++) {
711 			/* Look for best matches first */
712 			if ((sense_table[i][0] & drv_err) ==
713 			    sense_table[i][0]) {
714 				*sk = sense_table[i][1];
715 				*asc = sense_table[i][2];
716 				*ascq = sense_table[i][3];
717 				goto translate_done;
718 			}
719 		}
720 		/* No immediate match */
721 		if (verbose)
722 			printk(KERN_WARNING "ata%u: no sense translation for "
723 			       "error 0x%02x\n", id, drv_err);
724 	}
725 
726 	/* Fall back to interpreting status bits */
727 	for (i = 0; stat_table[i][0] != 0xFF; i++) {
728 		if (stat_table[i][0] & drv_stat) {
729 			*sk = stat_table[i][1];
730 			*asc = stat_table[i][2];
731 			*ascq = stat_table[i][3];
732 			goto translate_done;
733 		}
734 	}
735 	/* No error?  Undecoded? */
736 	if (verbose)
737 		printk(KERN_WARNING "ata%u: no sense translation for "
738 		       "status: 0x%02x\n", id, drv_stat);
739 
740 	/* We need a sensible error return here, which is tricky, and one
741 	   that won't cause people to do things like return a disk wrongly */
742 	*sk = ABORTED_COMMAND;
743 	*asc = 0x00;
744 	*ascq = 0x00;
745 
746  translate_done:
747 	if (verbose)
748 		printk(KERN_ERR "ata%u: translated ATA stat/err 0x%02x/%02x "
749 		       "to SCSI SK/ASC/ASCQ 0x%x/%02x/%02x\n",
750 		       id, drv_stat, drv_err, *sk, *asc, *ascq);
751 	return;
752 }
753 
754 /*
755  *	ata_gen_passthru_sense - Generate check condition sense block.
756  *	@qc: Command that completed.
757  *
758  *	This function is specific to the ATA descriptor format sense
759  *	block specified for the ATA pass through commands.  Regardless
760  *	of whether the command errored or not, return a sense
761  *	block. Copy all controller registers into the sense
762  *	block. Clear sense key, ASC & ASCQ if there is no error.
763  *
764  *	LOCKING:
765  *	None.
766  */
767 static void ata_gen_passthru_sense(struct ata_queued_cmd *qc)
768 {
769 	struct scsi_cmnd *cmd = qc->scsicmd;
770 	struct ata_taskfile *tf = &qc->result_tf;
771 	unsigned char *sb = cmd->sense_buffer;
772 	unsigned char *desc = sb + 8;
773 	int verbose = qc->ap->ops->error_handler == NULL;
774 
775 	memset(sb, 0, SCSI_SENSE_BUFFERSIZE);
776 
777 	cmd->result = (DRIVER_SENSE << 24) | SAM_STAT_CHECK_CONDITION;
778 
779 	/*
780 	 * Use ata_to_sense_error() to map status register bits
781 	 * onto sense key, asc & ascq.
782 	 */
783 	if (qc->err_mask ||
784 	    tf->command & (ATA_BUSY | ATA_DF | ATA_ERR | ATA_DRQ)) {
785 		ata_to_sense_error(qc->ap->print_id, tf->command, tf->feature,
786 				   &sb[1], &sb[2], &sb[3], verbose);
787 		sb[1] &= 0x0f;
788 	}
789 
790 	/*
791 	 * Sense data is current and format is descriptor.
792 	 */
793 	sb[0] = 0x72;
794 
795 	desc[0] = 0x09;
796 
797 	/* set length of additional sense data */
798 	sb[7] = 14;
799 	desc[1] = 12;
800 
801 	/*
802 	 * Copy registers into sense buffer.
803 	 */
804 	desc[2] = 0x00;
805 	desc[3] = tf->feature;	/* == error reg */
806 	desc[5] = tf->nsect;
807 	desc[7] = tf->lbal;
808 	desc[9] = tf->lbam;
809 	desc[11] = tf->lbah;
810 	desc[12] = tf->device;
811 	desc[13] = tf->command; /* == status reg */
812 
813 	/*
814 	 * Fill in Extend bit, and the high order bytes
815 	 * if applicable.
816 	 */
817 	if (tf->flags & ATA_TFLAG_LBA48) {
818 		desc[2] |= 0x01;
819 		desc[4] = tf->hob_nsect;
820 		desc[6] = tf->hob_lbal;
821 		desc[8] = tf->hob_lbam;
822 		desc[10] = tf->hob_lbah;
823 	}
824 }
825 
826 /**
827  *	ata_gen_ata_sense - generate a SCSI fixed sense block
828  *	@qc: Command that we are erroring out
829  *
830  *	Generate sense block for a failed ATA command @qc.  Descriptor
831  *	format is used to accomodate LBA48 block address.
832  *
833  *	LOCKING:
834  *	None.
835  */
836 static void ata_gen_ata_sense(struct ata_queued_cmd *qc)
837 {
838 	struct ata_device *dev = qc->dev;
839 	struct scsi_cmnd *cmd = qc->scsicmd;
840 	struct ata_taskfile *tf = &qc->result_tf;
841 	unsigned char *sb = cmd->sense_buffer;
842 	unsigned char *desc = sb + 8;
843 	int verbose = qc->ap->ops->error_handler == NULL;
844 	u64 block;
845 
846 	memset(sb, 0, SCSI_SENSE_BUFFERSIZE);
847 
848 	cmd->result = (DRIVER_SENSE << 24) | SAM_STAT_CHECK_CONDITION;
849 
850 	/* sense data is current and format is descriptor */
851 	sb[0] = 0x72;
852 
853 	/* Use ata_to_sense_error() to map status register bits
854 	 * onto sense key, asc & ascq.
855 	 */
856 	if (qc->err_mask ||
857 	    tf->command & (ATA_BUSY | ATA_DF | ATA_ERR | ATA_DRQ)) {
858 		ata_to_sense_error(qc->ap->print_id, tf->command, tf->feature,
859 				   &sb[1], &sb[2], &sb[3], verbose);
860 		sb[1] &= 0x0f;
861 	}
862 
863 	block = ata_tf_read_block(&qc->result_tf, dev);
864 
865 	/* information sense data descriptor */
866 	sb[7] = 12;
867 	desc[0] = 0x00;
868 	desc[1] = 10;
869 
870 	desc[2] |= 0x80;	/* valid */
871 	desc[6] = block >> 40;
872 	desc[7] = block >> 32;
873 	desc[8] = block >> 24;
874 	desc[9] = block >> 16;
875 	desc[10] = block >> 8;
876 	desc[11] = block;
877 }
878 
879 static void ata_scsi_sdev_config(struct scsi_device *sdev)
880 {
881 	sdev->use_10_for_rw = 1;
882 	sdev->use_10_for_ms = 1;
883 }
884 
885 static void ata_scsi_dev_config(struct scsi_device *sdev,
886 				struct ata_device *dev)
887 {
888 	/* configure max sectors */
889 	blk_queue_max_sectors(sdev->request_queue, dev->max_sectors);
890 
891 	/* SATA DMA transfers must be multiples of 4 byte, so
892 	 * we need to pad ATAPI transfers using an extra sg.
893 	 * Decrement max hw segments accordingly.
894 	 */
895 	if (dev->class == ATA_DEV_ATAPI) {
896 		request_queue_t *q = sdev->request_queue;
897 		blk_queue_max_hw_segments(q, q->max_hw_segments - 1);
898 	}
899 
900 	if (dev->flags & ATA_DFLAG_NCQ) {
901 		int depth;
902 
903 		depth = min(sdev->host->can_queue, ata_id_queue_depth(dev->id));
904 		depth = min(ATA_MAX_QUEUE - 1, depth);
905 		scsi_adjust_queue_depth(sdev, MSG_SIMPLE_TAG, depth);
906 	}
907 }
908 
909 /**
910  *	ata_scsi_slave_config - Set SCSI device attributes
911  *	@sdev: SCSI device to examine
912  *
913  *	This is called before we actually start reading
914  *	and writing to the device, to configure certain
915  *	SCSI mid-layer behaviors.
916  *
917  *	LOCKING:
918  *	Defined by SCSI layer.  We don't really care.
919  */
920 
921 int ata_scsi_slave_config(struct scsi_device *sdev)
922 {
923 	struct ata_port *ap = ata_shost_to_port(sdev->host);
924 	struct ata_device *dev = __ata_scsi_find_dev(ap, sdev);
925 
926 	ata_scsi_sdev_config(sdev);
927 
928 	blk_queue_max_phys_segments(sdev->request_queue, LIBATA_MAX_PRD);
929 
930 	if (dev)
931 		ata_scsi_dev_config(sdev, dev);
932 
933 	return 0;	/* scsi layer doesn't check return value, sigh */
934 }
935 
936 /**
937  *	ata_scsi_slave_destroy - SCSI device is about to be destroyed
938  *	@sdev: SCSI device to be destroyed
939  *
940  *	@sdev is about to be destroyed for hot/warm unplugging.  If
941  *	this unplugging was initiated by libata as indicated by NULL
942  *	dev->sdev, this function doesn't have to do anything.
943  *	Otherwise, SCSI layer initiated warm-unplug is in progress.
944  *	Clear dev->sdev, schedule the device for ATA detach and invoke
945  *	EH.
946  *
947  *	LOCKING:
948  *	Defined by SCSI layer.  We don't really care.
949  */
950 void ata_scsi_slave_destroy(struct scsi_device *sdev)
951 {
952 	struct ata_port *ap = ata_shost_to_port(sdev->host);
953 	unsigned long flags;
954 	struct ata_device *dev;
955 
956 	if (!ap->ops->error_handler)
957 		return;
958 
959 	spin_lock_irqsave(ap->lock, flags);
960 	dev = __ata_scsi_find_dev(ap, sdev);
961 	if (dev && dev->sdev) {
962 		/* SCSI device already in CANCEL state, no need to offline it */
963 		dev->sdev = NULL;
964 		dev->flags |= ATA_DFLAG_DETACH;
965 		ata_port_schedule_eh(ap);
966 	}
967 	spin_unlock_irqrestore(ap->lock, flags);
968 }
969 
970 /**
971  *	ata_scsi_change_queue_depth - SCSI callback for queue depth config
972  *	@sdev: SCSI device to configure queue depth for
973  *	@queue_depth: new queue depth
974  *
975  *	This is libata standard hostt->change_queue_depth callback.
976  *	SCSI will call into this callback when user tries to set queue
977  *	depth via sysfs.
978  *
979  *	LOCKING:
980  *	SCSI layer (we don't care)
981  *
982  *	RETURNS:
983  *	Newly configured queue depth.
984  */
985 int ata_scsi_change_queue_depth(struct scsi_device *sdev, int queue_depth)
986 {
987 	struct ata_port *ap = ata_shost_to_port(sdev->host);
988 	struct ata_device *dev;
989 	unsigned long flags;
990 
991 	if (queue_depth < 1 || queue_depth == sdev->queue_depth)
992 		return sdev->queue_depth;
993 
994 	dev = ata_scsi_find_dev(ap, sdev);
995 	if (!dev || !ata_dev_enabled(dev))
996 		return sdev->queue_depth;
997 
998 	/* NCQ enabled? */
999 	spin_lock_irqsave(ap->lock, flags);
1000 	dev->flags &= ~ATA_DFLAG_NCQ_OFF;
1001 	if (queue_depth == 1 || !ata_ncq_enabled(dev)) {
1002 		dev->flags |= ATA_DFLAG_NCQ_OFF;
1003 		queue_depth = 1;
1004 	}
1005 	spin_unlock_irqrestore(ap->lock, flags);
1006 
1007 	/* limit and apply queue depth */
1008 	queue_depth = min(queue_depth, sdev->host->can_queue);
1009 	queue_depth = min(queue_depth, ata_id_queue_depth(dev->id));
1010 	queue_depth = min(queue_depth, ATA_MAX_QUEUE - 1);
1011 
1012 	if (sdev->queue_depth == queue_depth)
1013 		return -EINVAL;
1014 
1015 	scsi_adjust_queue_depth(sdev, MSG_SIMPLE_TAG, queue_depth);
1016 	return queue_depth;
1017 }
1018 
1019 /**
1020  *	ata_scsi_start_stop_xlat - Translate SCSI START STOP UNIT command
1021  *	@qc: Storage for translated ATA taskfile
1022  *
1023  *	Sets up an ATA taskfile to issue STANDBY (to stop) or READ VERIFY
1024  *	(to start). Perhaps these commands should be preceded by
1025  *	CHECK POWER MODE to see what power mode the device is already in.
1026  *	[See SAT revision 5 at www.t10.org]
1027  *
1028  *	LOCKING:
1029  *	spin_lock_irqsave(host lock)
1030  *
1031  *	RETURNS:
1032  *	Zero on success, non-zero on error.
1033  */
1034 static unsigned int ata_scsi_start_stop_xlat(struct ata_queued_cmd *qc)
1035 {
1036 	struct scsi_cmnd *scmd = qc->scsicmd;
1037 	struct ata_taskfile *tf = &qc->tf;
1038 	const u8 *cdb = scmd->cmnd;
1039 
1040 	if (scmd->cmd_len < 5)
1041 		goto invalid_fld;
1042 
1043 	tf->flags |= ATA_TFLAG_DEVICE | ATA_TFLAG_ISADDR;
1044 	tf->protocol = ATA_PROT_NODATA;
1045 	if (cdb[1] & 0x1) {
1046 		;	/* ignore IMMED bit, violates sat-r05 */
1047 	}
1048 	if (cdb[4] & 0x2)
1049 		goto invalid_fld;       /* LOEJ bit set not supported */
1050 	if (((cdb[4] >> 4) & 0xf) != 0)
1051 		goto invalid_fld;       /* power conditions not supported */
1052 	if (cdb[4] & 0x1) {
1053 		tf->nsect = 1;	/* 1 sector, lba=0 */
1054 
1055 		if (qc->dev->flags & ATA_DFLAG_LBA) {
1056 			tf->flags |= ATA_TFLAG_LBA;
1057 
1058 			tf->lbah = 0x0;
1059 			tf->lbam = 0x0;
1060 			tf->lbal = 0x0;
1061 			tf->device |= ATA_LBA;
1062 		} else {
1063 			/* CHS */
1064 			tf->lbal = 0x1; /* sect */
1065 			tf->lbam = 0x0; /* cyl low */
1066 			tf->lbah = 0x0; /* cyl high */
1067 		}
1068 
1069 		tf->command = ATA_CMD_VERIFY;	/* READ VERIFY */
1070 	} else
1071 		/* Issue ATA STANDBY IMMEDIATE command */
1072 		tf->command = ATA_CMD_STANDBYNOW1;
1073 
1074 	/*
1075 	 * Standby and Idle condition timers could be implemented but that
1076 	 * would require libata to implement the Power condition mode page
1077 	 * and allow the user to change it. Changing mode pages requires
1078 	 * MODE SELECT to be implemented.
1079 	 */
1080 
1081 	return 0;
1082 
1083 invalid_fld:
1084 	ata_scsi_set_sense(scmd, ILLEGAL_REQUEST, 0x24, 0x0);
1085 	/* "Invalid field in cbd" */
1086 	return 1;
1087 }
1088 
1089 
1090 /**
1091  *	ata_scsi_flush_xlat - Translate SCSI SYNCHRONIZE CACHE command
1092  *	@qc: Storage for translated ATA taskfile
1093  *
1094  *	Sets up an ATA taskfile to issue FLUSH CACHE or
1095  *	FLUSH CACHE EXT.
1096  *
1097  *	LOCKING:
1098  *	spin_lock_irqsave(host lock)
1099  *
1100  *	RETURNS:
1101  *	Zero on success, non-zero on error.
1102  */
1103 static unsigned int ata_scsi_flush_xlat(struct ata_queued_cmd *qc)
1104 {
1105 	struct ata_taskfile *tf = &qc->tf;
1106 
1107 	tf->flags |= ATA_TFLAG_DEVICE;
1108 	tf->protocol = ATA_PROT_NODATA;
1109 
1110 	if (qc->dev->flags & ATA_DFLAG_FLUSH_EXT)
1111 		tf->command = ATA_CMD_FLUSH_EXT;
1112 	else
1113 		tf->command = ATA_CMD_FLUSH;
1114 
1115 	return 0;
1116 }
1117 
1118 /**
1119  *	scsi_6_lba_len - Get LBA and transfer length
1120  *	@cdb: SCSI command to translate
1121  *
1122  *	Calculate LBA and transfer length for 6-byte commands.
1123  *
1124  *	RETURNS:
1125  *	@plba: the LBA
1126  *	@plen: the transfer length
1127  */
1128 static void scsi_6_lba_len(const u8 *cdb, u64 *plba, u32 *plen)
1129 {
1130 	u64 lba = 0;
1131 	u32 len = 0;
1132 
1133 	VPRINTK("six-byte command\n");
1134 
1135 	lba |= ((u64)cdb[2]) << 8;
1136 	lba |= ((u64)cdb[3]);
1137 
1138 	len |= ((u32)cdb[4]);
1139 
1140 	*plba = lba;
1141 	*plen = len;
1142 }
1143 
1144 /**
1145  *	scsi_10_lba_len - Get LBA and transfer length
1146  *	@cdb: SCSI command to translate
1147  *
1148  *	Calculate LBA and transfer length for 10-byte commands.
1149  *
1150  *	RETURNS:
1151  *	@plba: the LBA
1152  *	@plen: the transfer length
1153  */
1154 static void scsi_10_lba_len(const u8 *cdb, u64 *plba, u32 *plen)
1155 {
1156 	u64 lba = 0;
1157 	u32 len = 0;
1158 
1159 	VPRINTK("ten-byte command\n");
1160 
1161 	lba |= ((u64)cdb[2]) << 24;
1162 	lba |= ((u64)cdb[3]) << 16;
1163 	lba |= ((u64)cdb[4]) << 8;
1164 	lba |= ((u64)cdb[5]);
1165 
1166 	len |= ((u32)cdb[7]) << 8;
1167 	len |= ((u32)cdb[8]);
1168 
1169 	*plba = lba;
1170 	*plen = len;
1171 }
1172 
1173 /**
1174  *	scsi_16_lba_len - Get LBA and transfer length
1175  *	@cdb: SCSI command to translate
1176  *
1177  *	Calculate LBA and transfer length for 16-byte commands.
1178  *
1179  *	RETURNS:
1180  *	@plba: the LBA
1181  *	@plen: the transfer length
1182  */
1183 static void scsi_16_lba_len(const u8 *cdb, u64 *plba, u32 *plen)
1184 {
1185 	u64 lba = 0;
1186 	u32 len = 0;
1187 
1188 	VPRINTK("sixteen-byte command\n");
1189 
1190 	lba |= ((u64)cdb[2]) << 56;
1191 	lba |= ((u64)cdb[3]) << 48;
1192 	lba |= ((u64)cdb[4]) << 40;
1193 	lba |= ((u64)cdb[5]) << 32;
1194 	lba |= ((u64)cdb[6]) << 24;
1195 	lba |= ((u64)cdb[7]) << 16;
1196 	lba |= ((u64)cdb[8]) << 8;
1197 	lba |= ((u64)cdb[9]);
1198 
1199 	len |= ((u32)cdb[10]) << 24;
1200 	len |= ((u32)cdb[11]) << 16;
1201 	len |= ((u32)cdb[12]) << 8;
1202 	len |= ((u32)cdb[13]);
1203 
1204 	*plba = lba;
1205 	*plen = len;
1206 }
1207 
1208 /**
1209  *	ata_scsi_verify_xlat - Translate SCSI VERIFY command into an ATA one
1210  *	@qc: Storage for translated ATA taskfile
1211  *
1212  *	Converts SCSI VERIFY command to an ATA READ VERIFY command.
1213  *
1214  *	LOCKING:
1215  *	spin_lock_irqsave(host lock)
1216  *
1217  *	RETURNS:
1218  *	Zero on success, non-zero on error.
1219  */
1220 static unsigned int ata_scsi_verify_xlat(struct ata_queued_cmd *qc)
1221 {
1222 	struct scsi_cmnd *scmd = qc->scsicmd;
1223 	struct ata_taskfile *tf = &qc->tf;
1224 	struct ata_device *dev = qc->dev;
1225 	u64 dev_sectors = qc->dev->n_sectors;
1226 	const u8 *cdb = scmd->cmnd;
1227 	u64 block;
1228 	u32 n_block;
1229 
1230 	tf->flags |= ATA_TFLAG_ISADDR | ATA_TFLAG_DEVICE;
1231 	tf->protocol = ATA_PROT_NODATA;
1232 
1233 	if (cdb[0] == VERIFY) {
1234 		if (scmd->cmd_len < 10)
1235 			goto invalid_fld;
1236 		scsi_10_lba_len(cdb, &block, &n_block);
1237 	} else if (cdb[0] == VERIFY_16) {
1238 		if (scmd->cmd_len < 16)
1239 			goto invalid_fld;
1240 		scsi_16_lba_len(cdb, &block, &n_block);
1241 	} else
1242 		goto invalid_fld;
1243 
1244 	if (!n_block)
1245 		goto nothing_to_do;
1246 	if (block >= dev_sectors)
1247 		goto out_of_range;
1248 	if ((block + n_block) > dev_sectors)
1249 		goto out_of_range;
1250 
1251 	if (dev->flags & ATA_DFLAG_LBA) {
1252 		tf->flags |= ATA_TFLAG_LBA;
1253 
1254 		if (lba_28_ok(block, n_block)) {
1255 			/* use LBA28 */
1256 			tf->command = ATA_CMD_VERIFY;
1257 			tf->device |= (block >> 24) & 0xf;
1258 		} else if (lba_48_ok(block, n_block)) {
1259 			if (!(dev->flags & ATA_DFLAG_LBA48))
1260 				goto out_of_range;
1261 
1262 			/* use LBA48 */
1263 			tf->flags |= ATA_TFLAG_LBA48;
1264 			tf->command = ATA_CMD_VERIFY_EXT;
1265 
1266 			tf->hob_nsect = (n_block >> 8) & 0xff;
1267 
1268 			tf->hob_lbah = (block >> 40) & 0xff;
1269 			tf->hob_lbam = (block >> 32) & 0xff;
1270 			tf->hob_lbal = (block >> 24) & 0xff;
1271 		} else
1272 			/* request too large even for LBA48 */
1273 			goto out_of_range;
1274 
1275 		tf->nsect = n_block & 0xff;
1276 
1277 		tf->lbah = (block >> 16) & 0xff;
1278 		tf->lbam = (block >> 8) & 0xff;
1279 		tf->lbal = block & 0xff;
1280 
1281 		tf->device |= ATA_LBA;
1282 	} else {
1283 		/* CHS */
1284 		u32 sect, head, cyl, track;
1285 
1286 		if (!lba_28_ok(block, n_block))
1287 			goto out_of_range;
1288 
1289 		/* Convert LBA to CHS */
1290 		track = (u32)block / dev->sectors;
1291 		cyl   = track / dev->heads;
1292 		head  = track % dev->heads;
1293 		sect  = (u32)block % dev->sectors + 1;
1294 
1295 		DPRINTK("block %u track %u cyl %u head %u sect %u\n",
1296 			(u32)block, track, cyl, head, sect);
1297 
1298 		/* Check whether the converted CHS can fit.
1299 		   Cylinder: 0-65535
1300 		   Head: 0-15
1301 		   Sector: 1-255*/
1302 		if ((cyl >> 16) || (head >> 4) || (sect >> 8) || (!sect))
1303 			goto out_of_range;
1304 
1305 		tf->command = ATA_CMD_VERIFY;
1306 		tf->nsect = n_block & 0xff; /* Sector count 0 means 256 sectors */
1307 		tf->lbal = sect;
1308 		tf->lbam = cyl;
1309 		tf->lbah = cyl >> 8;
1310 		tf->device |= head;
1311 	}
1312 
1313 	return 0;
1314 
1315 invalid_fld:
1316 	ata_scsi_set_sense(scmd, ILLEGAL_REQUEST, 0x24, 0x0);
1317 	/* "Invalid field in cbd" */
1318 	return 1;
1319 
1320 out_of_range:
1321 	ata_scsi_set_sense(scmd, ILLEGAL_REQUEST, 0x21, 0x0);
1322 	/* "Logical Block Address out of range" */
1323 	return 1;
1324 
1325 nothing_to_do:
1326 	scmd->result = SAM_STAT_GOOD;
1327 	return 1;
1328 }
1329 
1330 /**
1331  *	ata_scsi_rw_xlat - Translate SCSI r/w command into an ATA one
1332  *	@qc: Storage for translated ATA taskfile
1333  *
1334  *	Converts any of six SCSI read/write commands into the
1335  *	ATA counterpart, including starting sector (LBA),
1336  *	sector count, and taking into account the device's LBA48
1337  *	support.
1338  *
1339  *	Commands %READ_6, %READ_10, %READ_16, %WRITE_6, %WRITE_10, and
1340  *	%WRITE_16 are currently supported.
1341  *
1342  *	LOCKING:
1343  *	spin_lock_irqsave(host lock)
1344  *
1345  *	RETURNS:
1346  *	Zero on success, non-zero on error.
1347  */
1348 static unsigned int ata_scsi_rw_xlat(struct ata_queued_cmd *qc)
1349 {
1350 	struct scsi_cmnd *scmd = qc->scsicmd;
1351 	const u8 *cdb = scmd->cmnd;
1352 	unsigned int tf_flags = 0;
1353 	u64 block;
1354 	u32 n_block;
1355 	int rc;
1356 
1357 	if (cdb[0] == WRITE_10 || cdb[0] == WRITE_6 || cdb[0] == WRITE_16)
1358 		tf_flags |= ATA_TFLAG_WRITE;
1359 
1360 	/* Calculate the SCSI LBA, transfer length and FUA. */
1361 	switch (cdb[0]) {
1362 	case READ_10:
1363 	case WRITE_10:
1364 		if (unlikely(scmd->cmd_len < 10))
1365 			goto invalid_fld;
1366 		scsi_10_lba_len(cdb, &block, &n_block);
1367 		if (unlikely(cdb[1] & (1 << 3)))
1368 			tf_flags |= ATA_TFLAG_FUA;
1369 		break;
1370 	case READ_6:
1371 	case WRITE_6:
1372 		if (unlikely(scmd->cmd_len < 6))
1373 			goto invalid_fld;
1374 		scsi_6_lba_len(cdb, &block, &n_block);
1375 
1376 		/* for 6-byte r/w commands, transfer length 0
1377 		 * means 256 blocks of data, not 0 block.
1378 		 */
1379 		if (!n_block)
1380 			n_block = 256;
1381 		break;
1382 	case READ_16:
1383 	case WRITE_16:
1384 		if (unlikely(scmd->cmd_len < 16))
1385 			goto invalid_fld;
1386 		scsi_16_lba_len(cdb, &block, &n_block);
1387 		if (unlikely(cdb[1] & (1 << 3)))
1388 			tf_flags |= ATA_TFLAG_FUA;
1389 		break;
1390 	default:
1391 		DPRINTK("no-byte command\n");
1392 		goto invalid_fld;
1393 	}
1394 
1395 	/* Check and compose ATA command */
1396 	if (!n_block)
1397 		/* For 10-byte and 16-byte SCSI R/W commands, transfer
1398 		 * length 0 means transfer 0 block of data.
1399 		 * However, for ATA R/W commands, sector count 0 means
1400 		 * 256 or 65536 sectors, not 0 sectors as in SCSI.
1401 		 *
1402 		 * WARNING: one or two older ATA drives treat 0 as 0...
1403 		 */
1404 		goto nothing_to_do;
1405 
1406 	qc->flags |= ATA_QCFLAG_IO;
1407 	qc->nbytes = n_block * ATA_SECT_SIZE;
1408 
1409 	rc = ata_build_rw_tf(&qc->tf, qc->dev, block, n_block, tf_flags,
1410 			     qc->tag);
1411 	if (likely(rc == 0))
1412 		return 0;
1413 
1414 	if (rc == -ERANGE)
1415 		goto out_of_range;
1416 	/* treat all other errors as -EINVAL, fall through */
1417 invalid_fld:
1418 	ata_scsi_set_sense(scmd, ILLEGAL_REQUEST, 0x24, 0x0);
1419 	/* "Invalid field in cbd" */
1420 	return 1;
1421 
1422 out_of_range:
1423 	ata_scsi_set_sense(scmd, ILLEGAL_REQUEST, 0x21, 0x0);
1424 	/* "Logical Block Address out of range" */
1425 	return 1;
1426 
1427 nothing_to_do:
1428 	scmd->result = SAM_STAT_GOOD;
1429 	return 1;
1430 }
1431 
1432 static void ata_scsi_qc_complete(struct ata_queued_cmd *qc)
1433 {
1434 	struct ata_port *ap = qc->ap;
1435 	struct scsi_cmnd *cmd = qc->scsicmd;
1436 	u8 *cdb = cmd->cmnd;
1437  	int need_sense = (qc->err_mask != 0);
1438 
1439 	/* We snoop the SET_FEATURES - Write Cache ON/OFF command, and
1440 	 * schedule EH_REVALIDATE operation to update the IDENTIFY DEVICE
1441 	 * cache
1442 	 */
1443 	if (ap->ops->error_handler &&
1444 	    !need_sense && (qc->tf.command == ATA_CMD_SET_FEATURES) &&
1445 	    ((qc->tf.feature == SETFEATURES_WC_ON) ||
1446 	     (qc->tf.feature == SETFEATURES_WC_OFF))) {
1447 		ap->eh_info.action |= ATA_EH_REVALIDATE;
1448 		ata_port_schedule_eh(ap);
1449 	}
1450 
1451 	/* For ATA pass thru (SAT) commands, generate a sense block if
1452 	 * user mandated it or if there's an error.  Note that if we
1453 	 * generate because the user forced us to, a check condition
1454 	 * is generated and the ATA register values are returned
1455 	 * whether the command completed successfully or not. If there
1456 	 * was no error, SK, ASC and ASCQ will all be zero.
1457 	 */
1458 	if (((cdb[0] == ATA_16) || (cdb[0] == ATA_12)) &&
1459  	    ((cdb[2] & 0x20) || need_sense)) {
1460 		ata_gen_passthru_sense(qc);
1461 	} else {
1462 		if (!need_sense) {
1463 			cmd->result = SAM_STAT_GOOD;
1464 		} else {
1465 			/* TODO: decide which descriptor format to use
1466 			 * for 48b LBA devices and call that here
1467 			 * instead of the fixed desc, which is only
1468 			 * good for smaller LBA (and maybe CHS?)
1469 			 * devices.
1470 			 */
1471 			ata_gen_ata_sense(qc);
1472 		}
1473 	}
1474 
1475 	if (need_sense && !ap->ops->error_handler)
1476 		ata_dump_status(ap->print_id, &qc->result_tf);
1477 
1478 	qc->scsidone(cmd);
1479 
1480 	ata_qc_free(qc);
1481 }
1482 
1483 /**
1484  *	ata_scmd_need_defer - Check whether we need to defer scmd
1485  *	@dev: ATA device to which the command is addressed
1486  *	@is_io: Is the command IO (and thus possibly NCQ)?
1487  *
1488  *	NCQ and non-NCQ commands cannot run together.  As upper layer
1489  *	only knows the queue depth, we are responsible for maintaining
1490  *	exclusion.  This function checks whether a new command can be
1491  *	issued to @dev.
1492  *
1493  *	LOCKING:
1494  *	spin_lock_irqsave(host lock)
1495  *
1496  *	RETURNS:
1497  *	1 if deferring is needed, 0 otherwise.
1498  */
1499 static int ata_scmd_need_defer(struct ata_device *dev, int is_io)
1500 {
1501 	struct ata_port *ap = dev->ap;
1502 	int is_ncq = is_io && ata_ncq_enabled(dev);
1503 
1504 	if (is_ncq) {
1505 		if (!ata_tag_valid(ap->active_tag))
1506 			return 0;
1507 	} else {
1508 		if (!ata_tag_valid(ap->active_tag) && !ap->sactive)
1509 			return 0;
1510 	}
1511 	return 1;
1512 }
1513 
1514 /**
1515  *	ata_scsi_translate - Translate then issue SCSI command to ATA device
1516  *	@dev: ATA device to which the command is addressed
1517  *	@cmd: SCSI command to execute
1518  *	@done: SCSI command completion function
1519  *	@xlat_func: Actor which translates @cmd to an ATA taskfile
1520  *
1521  *	Our ->queuecommand() function has decided that the SCSI
1522  *	command issued can be directly translated into an ATA
1523  *	command, rather than handled internally.
1524  *
1525  *	This function sets up an ata_queued_cmd structure for the
1526  *	SCSI command, and sends that ata_queued_cmd to the hardware.
1527  *
1528  *	The xlat_func argument (actor) returns 0 if ready to execute
1529  *	ATA command, else 1 to finish translation. If 1 is returned
1530  *	then cmd->result (and possibly cmd->sense_buffer) are assumed
1531  *	to be set reflecting an error condition or clean (early)
1532  *	termination.
1533  *
1534  *	LOCKING:
1535  *	spin_lock_irqsave(host lock)
1536  *
1537  *	RETURNS:
1538  *	0 on success, SCSI_ML_QUEUE_DEVICE_BUSY if the command
1539  *	needs to be deferred.
1540  */
1541 static int ata_scsi_translate(struct ata_device *dev, struct scsi_cmnd *cmd,
1542 			      void (*done)(struct scsi_cmnd *),
1543 			      ata_xlat_func_t xlat_func)
1544 {
1545 	struct ata_queued_cmd *qc;
1546 	int is_io = xlat_func == ata_scsi_rw_xlat;
1547 
1548 	VPRINTK("ENTER\n");
1549 
1550 	if (unlikely(ata_scmd_need_defer(dev, is_io)))
1551 		goto defer;
1552 
1553 	qc = ata_scsi_qc_new(dev, cmd, done);
1554 	if (!qc)
1555 		goto err_mem;
1556 
1557 	/* data is present; dma-map it */
1558 	if (cmd->sc_data_direction == DMA_FROM_DEVICE ||
1559 	    cmd->sc_data_direction == DMA_TO_DEVICE) {
1560 		if (unlikely(cmd->request_bufflen < 1)) {
1561 			ata_dev_printk(dev, KERN_WARNING,
1562 				       "WARNING: zero len r/w req\n");
1563 			goto err_did;
1564 		}
1565 
1566 		if (cmd->use_sg)
1567 			ata_sg_init(qc, cmd->request_buffer, cmd->use_sg);
1568 		else
1569 			ata_sg_init_one(qc, cmd->request_buffer,
1570 					cmd->request_bufflen);
1571 
1572 		qc->dma_dir = cmd->sc_data_direction;
1573 	}
1574 
1575 	qc->complete_fn = ata_scsi_qc_complete;
1576 
1577 	if (xlat_func(qc))
1578 		goto early_finish;
1579 
1580 	/* select device, send command to hardware */
1581 	ata_qc_issue(qc);
1582 
1583 	VPRINTK("EXIT\n");
1584 	return 0;
1585 
1586 early_finish:
1587         ata_qc_free(qc);
1588 	done(cmd);
1589 	DPRINTK("EXIT - early finish (good or error)\n");
1590 	return 0;
1591 
1592 err_did:
1593 	ata_qc_free(qc);
1594 	cmd->result = (DID_ERROR << 16);
1595 	done(cmd);
1596 err_mem:
1597 	DPRINTK("EXIT - internal\n");
1598 	return 0;
1599 
1600 defer:
1601 	DPRINTK("EXIT - defer\n");
1602 	return SCSI_MLQUEUE_DEVICE_BUSY;
1603 }
1604 
1605 /**
1606  *	ata_scsi_rbuf_get - Map response buffer.
1607  *	@cmd: SCSI command containing buffer to be mapped.
1608  *	@buf_out: Pointer to mapped area.
1609  *
1610  *	Maps buffer contained within SCSI command @cmd.
1611  *
1612  *	LOCKING:
1613  *	spin_lock_irqsave(host lock)
1614  *
1615  *	RETURNS:
1616  *	Length of response buffer.
1617  */
1618 
1619 static unsigned int ata_scsi_rbuf_get(struct scsi_cmnd *cmd, u8 **buf_out)
1620 {
1621 	u8 *buf;
1622 	unsigned int buflen;
1623 
1624 	if (cmd->use_sg) {
1625 		struct scatterlist *sg;
1626 
1627 		sg = (struct scatterlist *) cmd->request_buffer;
1628 		buf = kmap_atomic(sg->page, KM_IRQ0) + sg->offset;
1629 		buflen = sg->length;
1630 	} else {
1631 		buf = cmd->request_buffer;
1632 		buflen = cmd->request_bufflen;
1633 	}
1634 
1635 	*buf_out = buf;
1636 	return buflen;
1637 }
1638 
1639 /**
1640  *	ata_scsi_rbuf_put - Unmap response buffer.
1641  *	@cmd: SCSI command containing buffer to be unmapped.
1642  *	@buf: buffer to unmap
1643  *
1644  *	Unmaps response buffer contained within @cmd.
1645  *
1646  *	LOCKING:
1647  *	spin_lock_irqsave(host lock)
1648  */
1649 
1650 static inline void ata_scsi_rbuf_put(struct scsi_cmnd *cmd, u8 *buf)
1651 {
1652 	if (cmd->use_sg) {
1653 		struct scatterlist *sg;
1654 
1655 		sg = (struct scatterlist *) cmd->request_buffer;
1656 		kunmap_atomic(buf - sg->offset, KM_IRQ0);
1657 	}
1658 }
1659 
1660 /**
1661  *	ata_scsi_rbuf_fill - wrapper for SCSI command simulators
1662  *	@args: device IDENTIFY data / SCSI command of interest.
1663  *	@actor: Callback hook for desired SCSI command simulator
1664  *
1665  *	Takes care of the hard work of simulating a SCSI command...
1666  *	Mapping the response buffer, calling the command's handler,
1667  *	and handling the handler's return value.  This return value
1668  *	indicates whether the handler wishes the SCSI command to be
1669  *	completed successfully (0), or not (in which case cmd->result
1670  *	and sense buffer are assumed to be set).
1671  *
1672  *	LOCKING:
1673  *	spin_lock_irqsave(host lock)
1674  */
1675 
1676 void ata_scsi_rbuf_fill(struct ata_scsi_args *args,
1677 		        unsigned int (*actor) (struct ata_scsi_args *args,
1678 			     		   u8 *rbuf, unsigned int buflen))
1679 {
1680 	u8 *rbuf;
1681 	unsigned int buflen, rc;
1682 	struct scsi_cmnd *cmd = args->cmd;
1683 
1684 	buflen = ata_scsi_rbuf_get(cmd, &rbuf);
1685 	memset(rbuf, 0, buflen);
1686 	rc = actor(args, rbuf, buflen);
1687 	ata_scsi_rbuf_put(cmd, rbuf);
1688 
1689 	if (rc == 0)
1690 		cmd->result = SAM_STAT_GOOD;
1691 	args->done(cmd);
1692 }
1693 
1694 /**
1695  *	ATA_SCSI_RBUF_SET - helper to set values in SCSI response buffer
1696  *	@idx: byte index into SCSI response buffer
1697  *	@val: value to set
1698  *
1699  *	To be used by SCSI command simulator functions.  This macros
1700  *	expects two local variables, u8 *rbuf and unsigned int buflen,
1701  *	are in scope.
1702  *
1703  *	LOCKING:
1704  *	None.
1705  */
1706 #define ATA_SCSI_RBUF_SET(idx, val) do { \
1707 		if ((idx) < buflen) rbuf[(idx)] = (u8)(val); \
1708 	} while (0)
1709 
1710 /**
1711  *	ata_scsiop_inq_std - Simulate INQUIRY command
1712  *	@args: device IDENTIFY data / SCSI command of interest.
1713  *	@rbuf: Response buffer, to which simulated SCSI cmd output is sent.
1714  *	@buflen: Response buffer length.
1715  *
1716  *	Returns standard device identification data associated
1717  *	with non-VPD INQUIRY command output.
1718  *
1719  *	LOCKING:
1720  *	spin_lock_irqsave(host lock)
1721  */
1722 
1723 unsigned int ata_scsiop_inq_std(struct ata_scsi_args *args, u8 *rbuf,
1724 			       unsigned int buflen)
1725 {
1726 	u8 hdr[] = {
1727 		TYPE_DISK,
1728 		0,
1729 		0x5,	/* claim SPC-3 version compatibility */
1730 		2,
1731 		95 - 4
1732 	};
1733 
1734 	/* set scsi removeable (RMB) bit per ata bit */
1735 	if (ata_id_removeable(args->id))
1736 		hdr[1] |= (1 << 7);
1737 
1738 	VPRINTK("ENTER\n");
1739 
1740 	memcpy(rbuf, hdr, sizeof(hdr));
1741 
1742 	if (buflen > 35) {
1743 		memcpy(&rbuf[8], "ATA     ", 8);
1744 		ata_id_string(args->id, &rbuf[16], ATA_ID_PROD, 16);
1745 		ata_id_string(args->id, &rbuf[32], ATA_ID_FW_REV, 4);
1746 		if (rbuf[32] == 0 || rbuf[32] == ' ')
1747 			memcpy(&rbuf[32], "n/a ", 4);
1748 	}
1749 
1750 	if (buflen > 63) {
1751 		const u8 versions[] = {
1752 			0x60,	/* SAM-3 (no version claimed) */
1753 
1754 			0x03,
1755 			0x20,	/* SBC-2 (no version claimed) */
1756 
1757 			0x02,
1758 			0x60	/* SPC-3 (no version claimed) */
1759 		};
1760 
1761 		memcpy(rbuf + 59, versions, sizeof(versions));
1762 	}
1763 
1764 	return 0;
1765 }
1766 
1767 /**
1768  *	ata_scsiop_inq_00 - Simulate INQUIRY VPD page 0, list of pages
1769  *	@args: device IDENTIFY data / SCSI command of interest.
1770  *	@rbuf: Response buffer, to which simulated SCSI cmd output is sent.
1771  *	@buflen: Response buffer length.
1772  *
1773  *	Returns list of inquiry VPD pages available.
1774  *
1775  *	LOCKING:
1776  *	spin_lock_irqsave(host lock)
1777  */
1778 
1779 unsigned int ata_scsiop_inq_00(struct ata_scsi_args *args, u8 *rbuf,
1780 			      unsigned int buflen)
1781 {
1782 	const u8 pages[] = {
1783 		0x00,	/* page 0x00, this page */
1784 		0x80,	/* page 0x80, unit serial no page */
1785 		0x83	/* page 0x83, device ident page */
1786 	};
1787 	rbuf[3] = sizeof(pages);	/* number of supported VPD pages */
1788 
1789 	if (buflen > 6)
1790 		memcpy(rbuf + 4, pages, sizeof(pages));
1791 
1792 	return 0;
1793 }
1794 
1795 /**
1796  *	ata_scsiop_inq_80 - Simulate INQUIRY VPD page 80, device serial number
1797  *	@args: device IDENTIFY data / SCSI command of interest.
1798  *	@rbuf: Response buffer, to which simulated SCSI cmd output is sent.
1799  *	@buflen: Response buffer length.
1800  *
1801  *	Returns ATA device serial number.
1802  *
1803  *	LOCKING:
1804  *	spin_lock_irqsave(host lock)
1805  */
1806 
1807 unsigned int ata_scsiop_inq_80(struct ata_scsi_args *args, u8 *rbuf,
1808 			      unsigned int buflen)
1809 {
1810 	const u8 hdr[] = {
1811 		0,
1812 		0x80,			/* this page code */
1813 		0,
1814 		ATA_ID_SERNO_LEN,	/* page len */
1815 	};
1816 	memcpy(rbuf, hdr, sizeof(hdr));
1817 
1818 	if (buflen > (ATA_ID_SERNO_LEN + 4 - 1))
1819 		ata_id_string(args->id, (unsigned char *) &rbuf[4],
1820 			      ATA_ID_SERNO, ATA_ID_SERNO_LEN);
1821 
1822 	return 0;
1823 }
1824 
1825 /**
1826  *	ata_scsiop_inq_83 - Simulate INQUIRY VPD page 83, device identity
1827  *	@args: device IDENTIFY data / SCSI command of interest.
1828  *	@rbuf: Response buffer, to which simulated SCSI cmd output is sent.
1829  *	@buflen: Response buffer length.
1830  *
1831  *	Yields two logical unit device identification designators:
1832  *	 - vendor specific ASCII containing the ATA serial number
1833  *	 - SAT defined "t10 vendor id based" containing ASCII vendor
1834  *	   name ("ATA     "), model and serial numbers.
1835  *
1836  *	LOCKING:
1837  *	spin_lock_irqsave(host lock)
1838  */
1839 
1840 unsigned int ata_scsiop_inq_83(struct ata_scsi_args *args, u8 *rbuf,
1841 			      unsigned int buflen)
1842 {
1843 	int num;
1844 	const int sat_model_serial_desc_len = 68;
1845 
1846 	rbuf[1] = 0x83;			/* this page code */
1847 	num = 4;
1848 
1849 	if (buflen > (ATA_ID_SERNO_LEN + num + 3)) {
1850 		/* piv=0, assoc=lu, code_set=ACSII, designator=vendor */
1851 		rbuf[num + 0] = 2;
1852 		rbuf[num + 3] = ATA_ID_SERNO_LEN;
1853 		num += 4;
1854 		ata_id_string(args->id, (unsigned char *) rbuf + num,
1855 			      ATA_ID_SERNO, ATA_ID_SERNO_LEN);
1856 		num += ATA_ID_SERNO_LEN;
1857 	}
1858 	if (buflen > (sat_model_serial_desc_len + num + 3)) {
1859 		/* SAT defined lu model and serial numbers descriptor */
1860 		/* piv=0, assoc=lu, code_set=ACSII, designator=t10 vendor id */
1861 		rbuf[num + 0] = 2;
1862 		rbuf[num + 1] = 1;
1863 		rbuf[num + 3] = sat_model_serial_desc_len;
1864 		num += 4;
1865 		memcpy(rbuf + num, "ATA     ", 8);
1866 		num += 8;
1867 		ata_id_string(args->id, (unsigned char *) rbuf + num,
1868 			      ATA_ID_PROD, ATA_ID_PROD_LEN);
1869 		num += ATA_ID_PROD_LEN;
1870 		ata_id_string(args->id, (unsigned char *) rbuf + num,
1871 			      ATA_ID_SERNO, ATA_ID_SERNO_LEN);
1872 		num += ATA_ID_SERNO_LEN;
1873 	}
1874 	rbuf[3] = num - 4;    /* page len (assume less than 256 bytes) */
1875 	return 0;
1876 }
1877 
1878 /**
1879  *	ata_scsiop_noop - Command handler that simply returns success.
1880  *	@args: device IDENTIFY data / SCSI command of interest.
1881  *	@rbuf: Response buffer, to which simulated SCSI cmd output is sent.
1882  *	@buflen: Response buffer length.
1883  *
1884  *	No operation.  Simply returns success to caller, to indicate
1885  *	that the caller should successfully complete this SCSI command.
1886  *
1887  *	LOCKING:
1888  *	spin_lock_irqsave(host lock)
1889  */
1890 
1891 unsigned int ata_scsiop_noop(struct ata_scsi_args *args, u8 *rbuf,
1892 			    unsigned int buflen)
1893 {
1894 	VPRINTK("ENTER\n");
1895 	return 0;
1896 }
1897 
1898 /**
1899  *	ata_msense_push - Push data onto MODE SENSE data output buffer
1900  *	@ptr_io: (input/output) Location to store more output data
1901  *	@last: End of output data buffer
1902  *	@buf: Pointer to BLOB being added to output buffer
1903  *	@buflen: Length of BLOB
1904  *
1905  *	Store MODE SENSE data on an output buffer.
1906  *
1907  *	LOCKING:
1908  *	None.
1909  */
1910 
1911 static void ata_msense_push(u8 **ptr_io, const u8 *last,
1912 			    const u8 *buf, unsigned int buflen)
1913 {
1914 	u8 *ptr = *ptr_io;
1915 
1916 	if ((ptr + buflen - 1) > last)
1917 		return;
1918 
1919 	memcpy(ptr, buf, buflen);
1920 
1921 	ptr += buflen;
1922 
1923 	*ptr_io = ptr;
1924 }
1925 
1926 /**
1927  *	ata_msense_caching - Simulate MODE SENSE caching info page
1928  *	@id: device IDENTIFY data
1929  *	@ptr_io: (input/output) Location to store more output data
1930  *	@last: End of output data buffer
1931  *
1932  *	Generate a caching info page, which conditionally indicates
1933  *	write caching to the SCSI layer, depending on device
1934  *	capabilities.
1935  *
1936  *	LOCKING:
1937  *	None.
1938  */
1939 
1940 static unsigned int ata_msense_caching(u16 *id, u8 **ptr_io,
1941 				       const u8 *last)
1942 {
1943 	u8 page[CACHE_MPAGE_LEN];
1944 
1945 	memcpy(page, def_cache_mpage, sizeof(page));
1946 	if (ata_id_wcache_enabled(id))
1947 		page[2] |= (1 << 2);	/* write cache enable */
1948 	if (!ata_id_rahead_enabled(id))
1949 		page[12] |= (1 << 5);	/* disable read ahead */
1950 
1951 	ata_msense_push(ptr_io, last, page, sizeof(page));
1952 	return sizeof(page);
1953 }
1954 
1955 /**
1956  *	ata_msense_ctl_mode - Simulate MODE SENSE control mode page
1957  *	@dev: Device associated with this MODE SENSE command
1958  *	@ptr_io: (input/output) Location to store more output data
1959  *	@last: End of output data buffer
1960  *
1961  *	Generate a generic MODE SENSE control mode page.
1962  *
1963  *	LOCKING:
1964  *	None.
1965  */
1966 
1967 static unsigned int ata_msense_ctl_mode(u8 **ptr_io, const u8 *last)
1968 {
1969 	ata_msense_push(ptr_io, last, def_control_mpage,
1970 			sizeof(def_control_mpage));
1971 	return sizeof(def_control_mpage);
1972 }
1973 
1974 /**
1975  *	ata_msense_rw_recovery - Simulate MODE SENSE r/w error recovery page
1976  *	@dev: Device associated with this MODE SENSE command
1977  *	@ptr_io: (input/output) Location to store more output data
1978  *	@last: End of output data buffer
1979  *
1980  *	Generate a generic MODE SENSE r/w error recovery page.
1981  *
1982  *	LOCKING:
1983  *	None.
1984  */
1985 
1986 static unsigned int ata_msense_rw_recovery(u8 **ptr_io, const u8 *last)
1987 {
1988 
1989 	ata_msense_push(ptr_io, last, def_rw_recovery_mpage,
1990 			sizeof(def_rw_recovery_mpage));
1991 	return sizeof(def_rw_recovery_mpage);
1992 }
1993 
1994 /*
1995  * We can turn this into a real blacklist if it's needed, for now just
1996  * blacklist any Maxtor BANC1G10 revision firmware
1997  */
1998 static int ata_dev_supports_fua(u16 *id)
1999 {
2000 	unsigned char model[ATA_ID_PROD_LEN + 1], fw[ATA_ID_FW_REV_LEN + 1];
2001 
2002 	if (!libata_fua)
2003 		return 0;
2004 	if (!ata_id_has_fua(id))
2005 		return 0;
2006 
2007 	ata_id_c_string(id, model, ATA_ID_PROD, sizeof(model));
2008 	ata_id_c_string(id, fw, ATA_ID_FW_REV, sizeof(fw));
2009 
2010 	if (strcmp(model, "Maxtor"))
2011 		return 1;
2012 	if (strcmp(fw, "BANC1G10"))
2013 		return 1;
2014 
2015 	return 0; /* blacklisted */
2016 }
2017 
2018 /**
2019  *	ata_scsiop_mode_sense - Simulate MODE SENSE 6, 10 commands
2020  *	@args: device IDENTIFY data / SCSI command of interest.
2021  *	@rbuf: Response buffer, to which simulated SCSI cmd output is sent.
2022  *	@buflen: Response buffer length.
2023  *
2024  *	Simulate MODE SENSE commands. Assume this is invoked for direct
2025  *	access devices (e.g. disks) only. There should be no block
2026  *	descriptor for other device types.
2027  *
2028  *	LOCKING:
2029  *	spin_lock_irqsave(host lock)
2030  */
2031 
2032 unsigned int ata_scsiop_mode_sense(struct ata_scsi_args *args, u8 *rbuf,
2033 				  unsigned int buflen)
2034 {
2035 	struct ata_device *dev = args->dev;
2036 	u8 *scsicmd = args->cmd->cmnd, *p, *last;
2037 	const u8 sat_blk_desc[] = {
2038 		0, 0, 0, 0,	/* number of blocks: sat unspecified */
2039 		0,
2040 		0, 0x2, 0x0	/* block length: 512 bytes */
2041 	};
2042 	u8 pg, spg;
2043 	unsigned int ebd, page_control, six_byte, output_len, alloc_len, minlen;
2044 	u8 dpofua;
2045 
2046 	VPRINTK("ENTER\n");
2047 
2048 	six_byte = (scsicmd[0] == MODE_SENSE);
2049 	ebd = !(scsicmd[1] & 0x8);      /* dbd bit inverted == edb */
2050 	/*
2051 	 * LLBA bit in msense(10) ignored (compliant)
2052 	 */
2053 
2054 	page_control = scsicmd[2] >> 6;
2055 	switch (page_control) {
2056 	case 0: /* current */
2057 		break;  /* supported */
2058 	case 3: /* saved */
2059 		goto saving_not_supp;
2060 	case 1: /* changeable */
2061 	case 2: /* defaults */
2062 	default:
2063 		goto invalid_fld;
2064 	}
2065 
2066 	if (six_byte) {
2067 		output_len = 4 + (ebd ? 8 : 0);
2068 		alloc_len = scsicmd[4];
2069 	} else {
2070 		output_len = 8 + (ebd ? 8 : 0);
2071 		alloc_len = (scsicmd[7] << 8) + scsicmd[8];
2072 	}
2073 	minlen = (alloc_len < buflen) ? alloc_len : buflen;
2074 
2075 	p = rbuf + output_len;
2076 	last = rbuf + minlen - 1;
2077 
2078 	pg = scsicmd[2] & 0x3f;
2079 	spg = scsicmd[3];
2080 	/*
2081 	 * No mode subpages supported (yet) but asking for _all_
2082 	 * subpages may be valid
2083 	 */
2084 	if (spg && (spg != ALL_SUB_MPAGES))
2085 		goto invalid_fld;
2086 
2087 	switch(pg) {
2088 	case RW_RECOVERY_MPAGE:
2089 		output_len += ata_msense_rw_recovery(&p, last);
2090 		break;
2091 
2092 	case CACHE_MPAGE:
2093 		output_len += ata_msense_caching(args->id, &p, last);
2094 		break;
2095 
2096 	case CONTROL_MPAGE: {
2097 		output_len += ata_msense_ctl_mode(&p, last);
2098 		break;
2099 		}
2100 
2101 	case ALL_MPAGES:
2102 		output_len += ata_msense_rw_recovery(&p, last);
2103 		output_len += ata_msense_caching(args->id, &p, last);
2104 		output_len += ata_msense_ctl_mode(&p, last);
2105 		break;
2106 
2107 	default:		/* invalid page code */
2108 		goto invalid_fld;
2109 	}
2110 
2111 	if (minlen < 1)
2112 		return 0;
2113 
2114 	dpofua = 0;
2115 	if (ata_dev_supports_fua(args->id) && (dev->flags & ATA_DFLAG_LBA48) &&
2116 	    (!(dev->flags & ATA_DFLAG_PIO) || dev->multi_count))
2117 		dpofua = 1 << 4;
2118 
2119 	if (six_byte) {
2120 		output_len--;
2121 		rbuf[0] = output_len;
2122 		if (minlen > 2)
2123 			rbuf[2] |= dpofua;
2124 		if (ebd) {
2125 			if (minlen > 3)
2126 				rbuf[3] = sizeof(sat_blk_desc);
2127 			if (minlen > 11)
2128 				memcpy(rbuf + 4, sat_blk_desc,
2129 				       sizeof(sat_blk_desc));
2130 		}
2131 	} else {
2132 		output_len -= 2;
2133 		rbuf[0] = output_len >> 8;
2134 		if (minlen > 1)
2135 			rbuf[1] = output_len;
2136 		if (minlen > 3)
2137 			rbuf[3] |= dpofua;
2138 		if (ebd) {
2139 			if (minlen > 7)
2140 				rbuf[7] = sizeof(sat_blk_desc);
2141 			if (minlen > 15)
2142 				memcpy(rbuf + 8, sat_blk_desc,
2143 				       sizeof(sat_blk_desc));
2144 		}
2145 	}
2146 	return 0;
2147 
2148 invalid_fld:
2149 	ata_scsi_set_sense(args->cmd, ILLEGAL_REQUEST, 0x24, 0x0);
2150 	/* "Invalid field in cbd" */
2151 	return 1;
2152 
2153 saving_not_supp:
2154 	ata_scsi_set_sense(args->cmd, ILLEGAL_REQUEST, 0x39, 0x0);
2155 	 /* "Saving parameters not supported" */
2156 	return 1;
2157 }
2158 
2159 /**
2160  *	ata_scsiop_read_cap - Simulate READ CAPACITY[ 16] commands
2161  *	@args: device IDENTIFY data / SCSI command of interest.
2162  *	@rbuf: Response buffer, to which simulated SCSI cmd output is sent.
2163  *	@buflen: Response buffer length.
2164  *
2165  *	Simulate READ CAPACITY commands.
2166  *
2167  *	LOCKING:
2168  *	None.
2169  */
2170 unsigned int ata_scsiop_read_cap(struct ata_scsi_args *args, u8 *rbuf,
2171 			        unsigned int buflen)
2172 {
2173 	u64 last_lba = args->dev->n_sectors - 1; /* LBA of the last block */
2174 
2175 	VPRINTK("ENTER\n");
2176 
2177 	if (args->cmd->cmnd[0] == READ_CAPACITY) {
2178 		if (last_lba >= 0xffffffffULL)
2179 			last_lba = 0xffffffff;
2180 
2181 		/* sector count, 32-bit */
2182 		ATA_SCSI_RBUF_SET(0, last_lba >> (8 * 3));
2183 		ATA_SCSI_RBUF_SET(1, last_lba >> (8 * 2));
2184 		ATA_SCSI_RBUF_SET(2, last_lba >> (8 * 1));
2185 		ATA_SCSI_RBUF_SET(3, last_lba);
2186 
2187 		/* sector size */
2188 		ATA_SCSI_RBUF_SET(6, ATA_SECT_SIZE >> 8);
2189 		ATA_SCSI_RBUF_SET(7, ATA_SECT_SIZE);
2190 	} else {
2191 		/* sector count, 64-bit */
2192 		ATA_SCSI_RBUF_SET(0, last_lba >> (8 * 7));
2193 		ATA_SCSI_RBUF_SET(1, last_lba >> (8 * 6));
2194 		ATA_SCSI_RBUF_SET(2, last_lba >> (8 * 5));
2195 		ATA_SCSI_RBUF_SET(3, last_lba >> (8 * 4));
2196 		ATA_SCSI_RBUF_SET(4, last_lba >> (8 * 3));
2197 		ATA_SCSI_RBUF_SET(5, last_lba >> (8 * 2));
2198 		ATA_SCSI_RBUF_SET(6, last_lba >> (8 * 1));
2199 		ATA_SCSI_RBUF_SET(7, last_lba);
2200 
2201 		/* sector size */
2202 		ATA_SCSI_RBUF_SET(10, ATA_SECT_SIZE >> 8);
2203 		ATA_SCSI_RBUF_SET(11, ATA_SECT_SIZE);
2204 	}
2205 
2206 	return 0;
2207 }
2208 
2209 /**
2210  *	ata_scsiop_report_luns - Simulate REPORT LUNS command
2211  *	@args: device IDENTIFY data / SCSI command of interest.
2212  *	@rbuf: Response buffer, to which simulated SCSI cmd output is sent.
2213  *	@buflen: Response buffer length.
2214  *
2215  *	Simulate REPORT LUNS command.
2216  *
2217  *	LOCKING:
2218  *	spin_lock_irqsave(host lock)
2219  */
2220 
2221 unsigned int ata_scsiop_report_luns(struct ata_scsi_args *args, u8 *rbuf,
2222 				   unsigned int buflen)
2223 {
2224 	VPRINTK("ENTER\n");
2225 	rbuf[3] = 8;	/* just one lun, LUN 0, size 8 bytes */
2226 
2227 	return 0;
2228 }
2229 
2230 /**
2231  *	ata_scsi_set_sense - Set SCSI sense data and status
2232  *	@cmd: SCSI request to be handled
2233  *	@sk: SCSI-defined sense key
2234  *	@asc: SCSI-defined additional sense code
2235  *	@ascq: SCSI-defined additional sense code qualifier
2236  *
2237  *	Helper function that builds a valid fixed format, current
2238  *	response code and the given sense key (sk), additional sense
2239  *	code (asc) and additional sense code qualifier (ascq) with
2240  *	a SCSI command status of %SAM_STAT_CHECK_CONDITION and
2241  *	DRIVER_SENSE set in the upper bits of scsi_cmnd::result .
2242  *
2243  *	LOCKING:
2244  *	Not required
2245  */
2246 
2247 void ata_scsi_set_sense(struct scsi_cmnd *cmd, u8 sk, u8 asc, u8 ascq)
2248 {
2249 	cmd->result = (DRIVER_SENSE << 24) | SAM_STAT_CHECK_CONDITION;
2250 
2251 	cmd->sense_buffer[0] = 0x70;	/* fixed format, current */
2252 	cmd->sense_buffer[2] = sk;
2253 	cmd->sense_buffer[7] = 18 - 8;	/* additional sense length */
2254 	cmd->sense_buffer[12] = asc;
2255 	cmd->sense_buffer[13] = ascq;
2256 }
2257 
2258 /**
2259  *	ata_scsi_badcmd - End a SCSI request with an error
2260  *	@cmd: SCSI request to be handled
2261  *	@done: SCSI command completion function
2262  *	@asc: SCSI-defined additional sense code
2263  *	@ascq: SCSI-defined additional sense code qualifier
2264  *
2265  *	Helper function that completes a SCSI command with
2266  *	%SAM_STAT_CHECK_CONDITION, with a sense key %ILLEGAL_REQUEST
2267  *	and the specified additional sense codes.
2268  *
2269  *	LOCKING:
2270  *	spin_lock_irqsave(host lock)
2271  */
2272 
2273 void ata_scsi_badcmd(struct scsi_cmnd *cmd, void (*done)(struct scsi_cmnd *), u8 asc, u8 ascq)
2274 {
2275 	DPRINTK("ENTER\n");
2276 	ata_scsi_set_sense(cmd, ILLEGAL_REQUEST, asc, ascq);
2277 
2278 	done(cmd);
2279 }
2280 
2281 static void atapi_sense_complete(struct ata_queued_cmd *qc)
2282 {
2283 	if (qc->err_mask && ((qc->err_mask & AC_ERR_DEV) == 0)) {
2284 		/* FIXME: not quite right; we don't want the
2285 		 * translation of taskfile registers into
2286 		 * a sense descriptors, since that's only
2287 		 * correct for ATA, not ATAPI
2288 		 */
2289 		ata_gen_passthru_sense(qc);
2290 	}
2291 
2292 	qc->scsidone(qc->scsicmd);
2293 	ata_qc_free(qc);
2294 }
2295 
2296 /* is it pointless to prefer PIO for "safety reasons"? */
2297 static inline int ata_pio_use_silly(struct ata_port *ap)
2298 {
2299 	return (ap->flags & ATA_FLAG_PIO_DMA);
2300 }
2301 
2302 static void atapi_request_sense(struct ata_queued_cmd *qc)
2303 {
2304 	struct ata_port *ap = qc->ap;
2305 	struct scsi_cmnd *cmd = qc->scsicmd;
2306 
2307 	DPRINTK("ATAPI request sense\n");
2308 
2309 	/* FIXME: is this needed? */
2310 	memset(cmd->sense_buffer, 0, sizeof(cmd->sense_buffer));
2311 
2312 	ap->ops->tf_read(ap, &qc->tf);
2313 
2314 	/* fill these in, for the case where they are -not- overwritten */
2315 	cmd->sense_buffer[0] = 0x70;
2316 	cmd->sense_buffer[2] = qc->tf.feature >> 4;
2317 
2318 	ata_qc_reinit(qc);
2319 
2320 	ata_sg_init_one(qc, cmd->sense_buffer, sizeof(cmd->sense_buffer));
2321 	qc->dma_dir = DMA_FROM_DEVICE;
2322 
2323 	memset(&qc->cdb, 0, qc->dev->cdb_len);
2324 	qc->cdb[0] = REQUEST_SENSE;
2325 	qc->cdb[4] = SCSI_SENSE_BUFFERSIZE;
2326 
2327 	qc->tf.flags |= ATA_TFLAG_ISADDR | ATA_TFLAG_DEVICE;
2328 	qc->tf.command = ATA_CMD_PACKET;
2329 
2330 	if (ata_pio_use_silly(ap)) {
2331 		qc->tf.protocol = ATA_PROT_ATAPI_DMA;
2332 		qc->tf.feature |= ATAPI_PKT_DMA;
2333 	} else {
2334 		qc->tf.protocol = ATA_PROT_ATAPI;
2335 		qc->tf.lbam = (8 * 1024) & 0xff;
2336 		qc->tf.lbah = (8 * 1024) >> 8;
2337 	}
2338 	qc->nbytes = SCSI_SENSE_BUFFERSIZE;
2339 
2340 	qc->complete_fn = atapi_sense_complete;
2341 
2342 	ata_qc_issue(qc);
2343 
2344 	DPRINTK("EXIT\n");
2345 }
2346 
2347 static void atapi_qc_complete(struct ata_queued_cmd *qc)
2348 {
2349 	struct scsi_cmnd *cmd = qc->scsicmd;
2350 	unsigned int err_mask = qc->err_mask;
2351 
2352 	VPRINTK("ENTER, err_mask 0x%X\n", err_mask);
2353 
2354 	/* handle completion from new EH */
2355 	if (unlikely(qc->ap->ops->error_handler &&
2356 		     (err_mask || qc->flags & ATA_QCFLAG_SENSE_VALID))) {
2357 
2358 		if (!(qc->flags & ATA_QCFLAG_SENSE_VALID)) {
2359 			/* FIXME: not quite right; we don't want the
2360 			 * translation of taskfile registers into a
2361 			 * sense descriptors, since that's only
2362 			 * correct for ATA, not ATAPI
2363 			 */
2364 			ata_gen_passthru_sense(qc);
2365 		}
2366 
2367 		/* SCSI EH automatically locks door if sdev->locked is
2368 		 * set.  Sometimes door lock request continues to
2369 		 * fail, for example, when no media is present.  This
2370 		 * creates a loop - SCSI EH issues door lock which
2371 		 * fails and gets invoked again to acquire sense data
2372 		 * for the failed command.
2373 		 *
2374 		 * If door lock fails, always clear sdev->locked to
2375 		 * avoid this infinite loop.
2376 		 */
2377 		if (qc->cdb[0] == ALLOW_MEDIUM_REMOVAL)
2378 			qc->dev->sdev->locked = 0;
2379 
2380 		qc->scsicmd->result = SAM_STAT_CHECK_CONDITION;
2381 		qc->scsidone(cmd);
2382 		ata_qc_free(qc);
2383 		return;
2384 	}
2385 
2386 	/* successful completion or old EH failure path */
2387 	if (unlikely(err_mask & AC_ERR_DEV)) {
2388 		cmd->result = SAM_STAT_CHECK_CONDITION;
2389 		atapi_request_sense(qc);
2390 		return;
2391 	} else if (unlikely(err_mask)) {
2392 		/* FIXME: not quite right; we don't want the
2393 		 * translation of taskfile registers into
2394 		 * a sense descriptors, since that's only
2395 		 * correct for ATA, not ATAPI
2396 		 */
2397 		ata_gen_passthru_sense(qc);
2398 	} else {
2399 		u8 *scsicmd = cmd->cmnd;
2400 
2401 		if ((scsicmd[0] == INQUIRY) && ((scsicmd[1] & 0x03) == 0)) {
2402 			u8 *buf = NULL;
2403 			unsigned int buflen;
2404 
2405 			buflen = ata_scsi_rbuf_get(cmd, &buf);
2406 
2407 	/* ATAPI devices typically report zero for their SCSI version,
2408 	 * and sometimes deviate from the spec WRT response data
2409 	 * format.  If SCSI version is reported as zero like normal,
2410 	 * then we make the following fixups:  1) Fake MMC-5 version,
2411 	 * to indicate to the Linux scsi midlayer this is a modern
2412 	 * device.  2) Ensure response data format / ATAPI information
2413 	 * are always correct.
2414 	 */
2415 			if (buf[2] == 0) {
2416 				buf[2] = 0x5;
2417 				buf[3] = 0x32;
2418 			}
2419 
2420 			ata_scsi_rbuf_put(cmd, buf);
2421 		}
2422 
2423 		cmd->result = SAM_STAT_GOOD;
2424 	}
2425 
2426 	qc->scsidone(cmd);
2427 	ata_qc_free(qc);
2428 }
2429 /**
2430  *	atapi_xlat - Initialize PACKET taskfile
2431  *	@qc: command structure to be initialized
2432  *
2433  *	LOCKING:
2434  *	spin_lock_irqsave(host lock)
2435  *
2436  *	RETURNS:
2437  *	Zero on success, non-zero on failure.
2438  */
2439 static unsigned int atapi_xlat(struct ata_queued_cmd *qc)
2440 {
2441 	struct scsi_cmnd *scmd = qc->scsicmd;
2442 	struct ata_device *dev = qc->dev;
2443 	int using_pio = (dev->flags & ATA_DFLAG_PIO);
2444 	int nodata = (scmd->sc_data_direction == DMA_NONE);
2445 
2446 	if (!using_pio)
2447 		/* Check whether ATAPI DMA is safe */
2448 		if (ata_check_atapi_dma(qc))
2449 			using_pio = 1;
2450 
2451 	memset(qc->cdb, 0, dev->cdb_len);
2452 	memcpy(qc->cdb, scmd->cmnd, scmd->cmd_len);
2453 
2454 	qc->complete_fn = atapi_qc_complete;
2455 
2456 	qc->tf.flags |= ATA_TFLAG_ISADDR | ATA_TFLAG_DEVICE;
2457 	if (scmd->sc_data_direction == DMA_TO_DEVICE) {
2458 		qc->tf.flags |= ATA_TFLAG_WRITE;
2459 		DPRINTK("direction: write\n");
2460 	}
2461 
2462 	qc->tf.command = ATA_CMD_PACKET;
2463 
2464 	/* no data, or PIO data xfer */
2465 	if (using_pio || nodata) {
2466 		if (nodata)
2467 			qc->tf.protocol = ATA_PROT_ATAPI_NODATA;
2468 		else
2469 			qc->tf.protocol = ATA_PROT_ATAPI;
2470 		qc->tf.lbam = (8 * 1024) & 0xff;
2471 		qc->tf.lbah = (8 * 1024) >> 8;
2472 	}
2473 
2474 	/* DMA data xfer */
2475 	else {
2476 		qc->tf.protocol = ATA_PROT_ATAPI_DMA;
2477 		qc->tf.feature |= ATAPI_PKT_DMA;
2478 
2479 		if (atapi_dmadir && (scmd->sc_data_direction != DMA_TO_DEVICE))
2480 			/* some SATA bridges need us to indicate data xfer direction */
2481 			qc->tf.feature |= ATAPI_DMADIR;
2482 	}
2483 
2484 	qc->nbytes = scmd->request_bufflen;
2485 
2486 	return 0;
2487 }
2488 
2489 static struct ata_device * ata_find_dev(struct ata_port *ap, int id)
2490 {
2491 	if (likely(id < ATA_MAX_DEVICES))
2492 		return &ap->device[id];
2493 	return NULL;
2494 }
2495 
2496 static struct ata_device * __ata_scsi_find_dev(struct ata_port *ap,
2497 					const struct scsi_device *scsidev)
2498 {
2499 	/* skip commands not addressed to targets we simulate */
2500 	if (unlikely(scsidev->channel || scsidev->lun))
2501 		return NULL;
2502 
2503 	return ata_find_dev(ap, scsidev->id);
2504 }
2505 
2506 /**
2507  *	ata_scsi_dev_enabled - determine if device is enabled
2508  *	@dev: ATA device
2509  *
2510  *	Determine if commands should be sent to the specified device.
2511  *
2512  *	LOCKING:
2513  *	spin_lock_irqsave(host lock)
2514  *
2515  *	RETURNS:
2516  *	0 if commands are not allowed / 1 if commands are allowed
2517  */
2518 
2519 static int ata_scsi_dev_enabled(struct ata_device *dev)
2520 {
2521 	if (unlikely(!ata_dev_enabled(dev)))
2522 		return 0;
2523 
2524 	if (!atapi_enabled || (dev->ap->flags & ATA_FLAG_NO_ATAPI)) {
2525 		if (unlikely(dev->class == ATA_DEV_ATAPI)) {
2526 			ata_dev_printk(dev, KERN_WARNING,
2527 				       "WARNING: ATAPI is %s, device ignored.\n",
2528 				       atapi_enabled ? "not supported with this driver" : "disabled");
2529 			return 0;
2530 		}
2531 	}
2532 
2533 	return 1;
2534 }
2535 
2536 /**
2537  *	ata_scsi_find_dev - lookup ata_device from scsi_cmnd
2538  *	@ap: ATA port to which the device is attached
2539  *	@scsidev: SCSI device from which we derive the ATA device
2540  *
2541  *	Given various information provided in struct scsi_cmnd,
2542  *	map that onto an ATA bus, and using that mapping
2543  *	determine which ata_device is associated with the
2544  *	SCSI command to be sent.
2545  *
2546  *	LOCKING:
2547  *	spin_lock_irqsave(host lock)
2548  *
2549  *	RETURNS:
2550  *	Associated ATA device, or %NULL if not found.
2551  */
2552 static struct ata_device *
2553 ata_scsi_find_dev(struct ata_port *ap, const struct scsi_device *scsidev)
2554 {
2555 	struct ata_device *dev = __ata_scsi_find_dev(ap, scsidev);
2556 
2557 	if (unlikely(!dev || !ata_scsi_dev_enabled(dev)))
2558 		return NULL;
2559 
2560 	return dev;
2561 }
2562 
2563 /*
2564  *	ata_scsi_map_proto - Map pass-thru protocol value to taskfile value.
2565  *	@byte1: Byte 1 from pass-thru CDB.
2566  *
2567  *	RETURNS:
2568  *	ATA_PROT_UNKNOWN if mapping failed/unimplemented, protocol otherwise.
2569  */
2570 static u8
2571 ata_scsi_map_proto(u8 byte1)
2572 {
2573 	switch((byte1 & 0x1e) >> 1) {
2574 		case 3:		/* Non-data */
2575 			return ATA_PROT_NODATA;
2576 
2577 		case 6:		/* DMA */
2578 			return ATA_PROT_DMA;
2579 
2580 		case 4:		/* PIO Data-in */
2581 		case 5:		/* PIO Data-out */
2582 			return ATA_PROT_PIO;
2583 
2584 		case 10:	/* Device Reset */
2585 		case 0:		/* Hard Reset */
2586 		case 1:		/* SRST */
2587 		case 2:		/* Bus Idle */
2588 		case 7:		/* Packet */
2589 		case 8:		/* DMA Queued */
2590 		case 9:		/* Device Diagnostic */
2591 		case 11:	/* UDMA Data-in */
2592 		case 12:	/* UDMA Data-Out */
2593 		case 13:	/* FPDMA */
2594 		default:	/* Reserved */
2595 			break;
2596 	}
2597 
2598 	return ATA_PROT_UNKNOWN;
2599 }
2600 
2601 /**
2602  *	ata_scsi_pass_thru - convert ATA pass-thru CDB to taskfile
2603  *	@qc: command structure to be initialized
2604  *
2605  *	Handles either 12 or 16-byte versions of the CDB.
2606  *
2607  *	RETURNS:
2608  *	Zero on success, non-zero on failure.
2609  */
2610 static unsigned int ata_scsi_pass_thru(struct ata_queued_cmd *qc)
2611 {
2612 	struct ata_taskfile *tf = &(qc->tf);
2613 	struct scsi_cmnd *scmd = qc->scsicmd;
2614 	struct ata_device *dev = qc->dev;
2615 	const u8 *cdb = scmd->cmnd;
2616 
2617 	if ((tf->protocol = ata_scsi_map_proto(cdb[1])) == ATA_PROT_UNKNOWN)
2618 		goto invalid_fld;
2619 
2620 	/* We may not issue DMA commands if no DMA mode is set */
2621 	if (tf->protocol == ATA_PROT_DMA && dev->dma_mode == 0)
2622 		goto invalid_fld;
2623 
2624 	if (cdb[1] & 0xe0)
2625 		/* PIO multi not supported yet */
2626 		goto invalid_fld;
2627 
2628 	/*
2629 	 * 12 and 16 byte CDBs use different offsets to
2630 	 * provide the various register values.
2631 	 */
2632 	if (cdb[0] == ATA_16) {
2633 		/*
2634 		 * 16-byte CDB - may contain extended commands.
2635 		 *
2636 		 * If that is the case, copy the upper byte register values.
2637 		 */
2638 		if (cdb[1] & 0x01) {
2639 			tf->hob_feature = cdb[3];
2640 			tf->hob_nsect = cdb[5];
2641 			tf->hob_lbal = cdb[7];
2642 			tf->hob_lbam = cdb[9];
2643 			tf->hob_lbah = cdb[11];
2644 			tf->flags |= ATA_TFLAG_LBA48;
2645 		} else
2646 			tf->flags &= ~ATA_TFLAG_LBA48;
2647 
2648 		/*
2649 		 * Always copy low byte, device and command registers.
2650 		 */
2651 		tf->feature = cdb[4];
2652 		tf->nsect = cdb[6];
2653 		tf->lbal = cdb[8];
2654 		tf->lbam = cdb[10];
2655 		tf->lbah = cdb[12];
2656 		tf->device = cdb[13];
2657 		tf->command = cdb[14];
2658 	} else {
2659 		/*
2660 		 * 12-byte CDB - incapable of extended commands.
2661 		 */
2662 		tf->flags &= ~ATA_TFLAG_LBA48;
2663 
2664 		tf->feature = cdb[3];
2665 		tf->nsect = cdb[4];
2666 		tf->lbal = cdb[5];
2667 		tf->lbam = cdb[6];
2668 		tf->lbah = cdb[7];
2669 		tf->device = cdb[8];
2670 		tf->command = cdb[9];
2671 	}
2672 	/*
2673 	 * If slave is possible, enforce correct master/slave bit
2674 	*/
2675 	if (qc->ap->flags & ATA_FLAG_SLAVE_POSS)
2676 		tf->device = qc->dev->devno ?
2677 			tf->device | ATA_DEV1 : tf->device & ~ATA_DEV1;
2678 
2679 	/*
2680 	 * Filter SET_FEATURES - XFER MODE command -- otherwise,
2681 	 * SET_FEATURES - XFER MODE must be preceded/succeeded
2682 	 * by an update to hardware-specific registers for each
2683 	 * controller (i.e. the reason for ->set_piomode(),
2684 	 * ->set_dmamode(), and ->post_set_mode() hooks).
2685 	 */
2686 	if ((tf->command == ATA_CMD_SET_FEATURES)
2687 	 && (tf->feature == SETFEATURES_XFER))
2688 		goto invalid_fld;
2689 
2690 	/*
2691 	 * Set flags so that all registers will be written,
2692 	 * and pass on write indication (used for PIO/DMA
2693 	 * setup.)
2694 	 */
2695 	tf->flags |= (ATA_TFLAG_ISADDR | ATA_TFLAG_DEVICE);
2696 
2697 	if (scmd->sc_data_direction == DMA_TO_DEVICE)
2698 		tf->flags |= ATA_TFLAG_WRITE;
2699 
2700 	/*
2701 	 * Set transfer length.
2702 	 *
2703 	 * TODO: find out if we need to do more here to
2704 	 *       cover scatter/gather case.
2705 	 */
2706 	qc->nbytes = scmd->request_bufflen;
2707 
2708 	/* request result TF */
2709 	qc->flags |= ATA_QCFLAG_RESULT_TF;
2710 
2711 	return 0;
2712 
2713  invalid_fld:
2714 	ata_scsi_set_sense(scmd, ILLEGAL_REQUEST, 0x24, 0x00);
2715 	/* "Invalid field in cdb" */
2716 	return 1;
2717 }
2718 
2719 /**
2720  *	ata_get_xlat_func - check if SCSI to ATA translation is possible
2721  *	@dev: ATA device
2722  *	@cmd: SCSI command opcode to consider
2723  *
2724  *	Look up the SCSI command given, and determine whether the
2725  *	SCSI command is to be translated or simulated.
2726  *
2727  *	RETURNS:
2728  *	Pointer to translation function if possible, %NULL if not.
2729  */
2730 
2731 static inline ata_xlat_func_t ata_get_xlat_func(struct ata_device *dev, u8 cmd)
2732 {
2733 	switch (cmd) {
2734 	case READ_6:
2735 	case READ_10:
2736 	case READ_16:
2737 
2738 	case WRITE_6:
2739 	case WRITE_10:
2740 	case WRITE_16:
2741 		return ata_scsi_rw_xlat;
2742 
2743 	case SYNCHRONIZE_CACHE:
2744 		if (ata_try_flush_cache(dev))
2745 			return ata_scsi_flush_xlat;
2746 		break;
2747 
2748 	case VERIFY:
2749 	case VERIFY_16:
2750 		return ata_scsi_verify_xlat;
2751 
2752 	case ATA_12:
2753 	case ATA_16:
2754 		return ata_scsi_pass_thru;
2755 
2756 	case START_STOP:
2757 		return ata_scsi_start_stop_xlat;
2758 	}
2759 
2760 	return NULL;
2761 }
2762 
2763 /**
2764  *	ata_scsi_dump_cdb - dump SCSI command contents to dmesg
2765  *	@ap: ATA port to which the command was being sent
2766  *	@cmd: SCSI command to dump
2767  *
2768  *	Prints the contents of a SCSI command via printk().
2769  */
2770 
2771 static inline void ata_scsi_dump_cdb(struct ata_port *ap,
2772 				     struct scsi_cmnd *cmd)
2773 {
2774 #ifdef ATA_DEBUG
2775 	struct scsi_device *scsidev = cmd->device;
2776 	u8 *scsicmd = cmd->cmnd;
2777 
2778 	DPRINTK("CDB (%u:%d,%d,%d) %02x %02x %02x %02x %02x %02x %02x %02x %02x\n",
2779 		ap->print_id,
2780 		scsidev->channel, scsidev->id, scsidev->lun,
2781 		scsicmd[0], scsicmd[1], scsicmd[2], scsicmd[3],
2782 		scsicmd[4], scsicmd[5], scsicmd[6], scsicmd[7],
2783 		scsicmd[8]);
2784 #endif
2785 }
2786 
2787 static inline int __ata_scsi_queuecmd(struct scsi_cmnd *scmd,
2788 				      void (*done)(struct scsi_cmnd *),
2789 				      struct ata_device *dev)
2790 {
2791 	int rc = 0;
2792 
2793 	if (unlikely(!scmd->cmd_len)) {
2794 		ata_dev_printk(dev, KERN_WARNING, "WARNING: zero len CDB\n");
2795 		scmd->result = DID_ERROR << 16;
2796 		done(scmd);
2797 		return 0;
2798 	}
2799 
2800 	if (dev->class == ATA_DEV_ATA) {
2801 		ata_xlat_func_t xlat_func = ata_get_xlat_func(dev,
2802 							      scmd->cmnd[0]);
2803 
2804 		if (xlat_func)
2805 			rc = ata_scsi_translate(dev, scmd, done, xlat_func);
2806 		else
2807 			ata_scsi_simulate(dev, scmd, done);
2808 	} else
2809 		rc = ata_scsi_translate(dev, scmd, done, atapi_xlat);
2810 
2811 	return rc;
2812 }
2813 
2814 /**
2815  *	ata_scsi_queuecmd - Issue SCSI cdb to libata-managed device
2816  *	@cmd: SCSI command to be sent
2817  *	@done: Completion function, called when command is complete
2818  *
2819  *	In some cases, this function translates SCSI commands into
2820  *	ATA taskfiles, and queues the taskfiles to be sent to
2821  *	hardware.  In other cases, this function simulates a
2822  *	SCSI device by evaluating and responding to certain
2823  *	SCSI commands.  This creates the overall effect of
2824  *	ATA and ATAPI devices appearing as SCSI devices.
2825  *
2826  *	LOCKING:
2827  *	Releases scsi-layer-held lock, and obtains host lock.
2828  *
2829  *	RETURNS:
2830  *	Return value from __ata_scsi_queuecmd() if @cmd can be queued,
2831  *	0 otherwise.
2832  */
2833 int ata_scsi_queuecmd(struct scsi_cmnd *cmd, void (*done)(struct scsi_cmnd *))
2834 {
2835 	struct ata_port *ap;
2836 	struct ata_device *dev;
2837 	struct scsi_device *scsidev = cmd->device;
2838 	struct Scsi_Host *shost = scsidev->host;
2839 	int rc = 0;
2840 
2841 	ap = ata_shost_to_port(shost);
2842 
2843 	spin_unlock(shost->host_lock);
2844 	spin_lock(ap->lock);
2845 
2846 	ata_scsi_dump_cdb(ap, cmd);
2847 
2848 	dev = ata_scsi_find_dev(ap, scsidev);
2849 	if (likely(dev))
2850 		rc = __ata_scsi_queuecmd(cmd, done, dev);
2851 	else {
2852 		cmd->result = (DID_BAD_TARGET << 16);
2853 		done(cmd);
2854 	}
2855 
2856 	spin_unlock(ap->lock);
2857 	spin_lock(shost->host_lock);
2858 	return rc;
2859 }
2860 
2861 /**
2862  *	ata_scsi_simulate - simulate SCSI command on ATA device
2863  *	@dev: the target device
2864  *	@cmd: SCSI command being sent to device.
2865  *	@done: SCSI command completion function.
2866  *
2867  *	Interprets and directly executes a select list of SCSI commands
2868  *	that can be handled internally.
2869  *
2870  *	LOCKING:
2871  *	spin_lock_irqsave(host lock)
2872  */
2873 
2874 void ata_scsi_simulate(struct ata_device *dev, struct scsi_cmnd *cmd,
2875 		      void (*done)(struct scsi_cmnd *))
2876 {
2877 	struct ata_scsi_args args;
2878 	const u8 *scsicmd = cmd->cmnd;
2879 
2880 	args.dev = dev;
2881 	args.id = dev->id;
2882 	args.cmd = cmd;
2883 	args.done = done;
2884 
2885 	switch(scsicmd[0]) {
2886 		/* no-op's, complete with success */
2887 		case SYNCHRONIZE_CACHE:
2888 		case REZERO_UNIT:
2889 		case SEEK_6:
2890 		case SEEK_10:
2891 		case TEST_UNIT_READY:
2892 		case FORMAT_UNIT:		/* FIXME: correct? */
2893 		case SEND_DIAGNOSTIC:		/* FIXME: correct? */
2894 			ata_scsi_rbuf_fill(&args, ata_scsiop_noop);
2895 			break;
2896 
2897 		case INQUIRY:
2898 			if (scsicmd[1] & 2)	           /* is CmdDt set?  */
2899 				ata_scsi_invalid_field(cmd, done);
2900 			else if ((scsicmd[1] & 1) == 0)    /* is EVPD clear? */
2901 				ata_scsi_rbuf_fill(&args, ata_scsiop_inq_std);
2902 			else if (scsicmd[2] == 0x00)
2903 				ata_scsi_rbuf_fill(&args, ata_scsiop_inq_00);
2904 			else if (scsicmd[2] == 0x80)
2905 				ata_scsi_rbuf_fill(&args, ata_scsiop_inq_80);
2906 			else if (scsicmd[2] == 0x83)
2907 				ata_scsi_rbuf_fill(&args, ata_scsiop_inq_83);
2908 			else
2909 				ata_scsi_invalid_field(cmd, done);
2910 			break;
2911 
2912 		case MODE_SENSE:
2913 		case MODE_SENSE_10:
2914 			ata_scsi_rbuf_fill(&args, ata_scsiop_mode_sense);
2915 			break;
2916 
2917 		case MODE_SELECT:	/* unconditionally return */
2918 		case MODE_SELECT_10:	/* bad-field-in-cdb */
2919 			ata_scsi_invalid_field(cmd, done);
2920 			break;
2921 
2922 		case READ_CAPACITY:
2923 			ata_scsi_rbuf_fill(&args, ata_scsiop_read_cap);
2924 			break;
2925 
2926 		case SERVICE_ACTION_IN:
2927 			if ((scsicmd[1] & 0x1f) == SAI_READ_CAPACITY_16)
2928 				ata_scsi_rbuf_fill(&args, ata_scsiop_read_cap);
2929 			else
2930 				ata_scsi_invalid_field(cmd, done);
2931 			break;
2932 
2933 		case REPORT_LUNS:
2934 			ata_scsi_rbuf_fill(&args, ata_scsiop_report_luns);
2935 			break;
2936 
2937 		/* mandatory commands we haven't implemented yet */
2938 		case REQUEST_SENSE:
2939 
2940 		/* all other commands */
2941 		default:
2942 			ata_scsi_set_sense(cmd, ILLEGAL_REQUEST, 0x20, 0x0);
2943 			/* "Invalid command operation code" */
2944 			done(cmd);
2945 			break;
2946 	}
2947 }
2948 
2949 void ata_scsi_scan_host(struct ata_port *ap)
2950 {
2951 	unsigned int i;
2952 
2953 	if (ap->flags & ATA_FLAG_DISABLED)
2954 		return;
2955 
2956 	for (i = 0; i < ATA_MAX_DEVICES; i++) {
2957 		struct ata_device *dev = &ap->device[i];
2958 		struct scsi_device *sdev;
2959 
2960 		if (!ata_dev_enabled(dev) || dev->sdev)
2961 			continue;
2962 
2963 		sdev = __scsi_add_device(ap->scsi_host, 0, i, 0, NULL);
2964 		if (!IS_ERR(sdev)) {
2965 			dev->sdev = sdev;
2966 			scsi_device_put(sdev);
2967 		}
2968 	}
2969 }
2970 
2971 /**
2972  *	ata_scsi_offline_dev - offline attached SCSI device
2973  *	@dev: ATA device to offline attached SCSI device for
2974  *
2975  *	This function is called from ata_eh_hotplug() and responsible
2976  *	for taking the SCSI device attached to @dev offline.  This
2977  *	function is called with host lock which protects dev->sdev
2978  *	against clearing.
2979  *
2980  *	LOCKING:
2981  *	spin_lock_irqsave(host lock)
2982  *
2983  *	RETURNS:
2984  *	1 if attached SCSI device exists, 0 otherwise.
2985  */
2986 int ata_scsi_offline_dev(struct ata_device *dev)
2987 {
2988 	if (dev->sdev) {
2989 		scsi_device_set_state(dev->sdev, SDEV_OFFLINE);
2990 		return 1;
2991 	}
2992 	return 0;
2993 }
2994 
2995 /**
2996  *	ata_scsi_remove_dev - remove attached SCSI device
2997  *	@dev: ATA device to remove attached SCSI device for
2998  *
2999  *	This function is called from ata_eh_scsi_hotplug() and
3000  *	responsible for removing the SCSI device attached to @dev.
3001  *
3002  *	LOCKING:
3003  *	Kernel thread context (may sleep).
3004  */
3005 static void ata_scsi_remove_dev(struct ata_device *dev)
3006 {
3007 	struct ata_port *ap = dev->ap;
3008 	struct scsi_device *sdev;
3009 	unsigned long flags;
3010 
3011 	/* Alas, we need to grab scan_mutex to ensure SCSI device
3012 	 * state doesn't change underneath us and thus
3013 	 * scsi_device_get() always succeeds.  The mutex locking can
3014 	 * be removed if there is __scsi_device_get() interface which
3015 	 * increments reference counts regardless of device state.
3016 	 */
3017 	mutex_lock(&ap->scsi_host->scan_mutex);
3018 	spin_lock_irqsave(ap->lock, flags);
3019 
3020 	/* clearing dev->sdev is protected by host lock */
3021 	sdev = dev->sdev;
3022 	dev->sdev = NULL;
3023 
3024 	if (sdev) {
3025 		/* If user initiated unplug races with us, sdev can go
3026 		 * away underneath us after the host lock and
3027 		 * scan_mutex are released.  Hold onto it.
3028 		 */
3029 		if (scsi_device_get(sdev) == 0) {
3030 			/* The following ensures the attached sdev is
3031 			 * offline on return from ata_scsi_offline_dev()
3032 			 * regardless it wins or loses the race
3033 			 * against this function.
3034 			 */
3035 			scsi_device_set_state(sdev, SDEV_OFFLINE);
3036 		} else {
3037 			WARN_ON(1);
3038 			sdev = NULL;
3039 		}
3040 	}
3041 
3042 	spin_unlock_irqrestore(ap->lock, flags);
3043 	mutex_unlock(&ap->scsi_host->scan_mutex);
3044 
3045 	if (sdev) {
3046 		ata_dev_printk(dev, KERN_INFO, "detaching (SCSI %s)\n",
3047 			       sdev->sdev_gendev.bus_id);
3048 
3049 		scsi_remove_device(sdev);
3050 		scsi_device_put(sdev);
3051 	}
3052 }
3053 
3054 /**
3055  *	ata_scsi_hotplug - SCSI part of hotplug
3056  *	@work: Pointer to ATA port to perform SCSI hotplug on
3057  *
3058  *	Perform SCSI part of hotplug.  It's executed from a separate
3059  *	workqueue after EH completes.  This is necessary because SCSI
3060  *	hot plugging requires working EH and hot unplugging is
3061  *	synchronized with hot plugging with a mutex.
3062  *
3063  *	LOCKING:
3064  *	Kernel thread context (may sleep).
3065  */
3066 void ata_scsi_hotplug(struct work_struct *work)
3067 {
3068 	struct ata_port *ap =
3069 		container_of(work, struct ata_port, hotplug_task.work);
3070 	int i;
3071 
3072 	if (ap->pflags & ATA_PFLAG_UNLOADING) {
3073 		DPRINTK("ENTER/EXIT - unloading\n");
3074 		return;
3075 	}
3076 
3077 	DPRINTK("ENTER\n");
3078 
3079 	/* unplug detached devices */
3080 	for (i = 0; i < ATA_MAX_DEVICES; i++) {
3081 		struct ata_device *dev = &ap->device[i];
3082 		unsigned long flags;
3083 
3084 		if (!(dev->flags & ATA_DFLAG_DETACHED))
3085 			continue;
3086 
3087 		spin_lock_irqsave(ap->lock, flags);
3088 		dev->flags &= ~ATA_DFLAG_DETACHED;
3089 		spin_unlock_irqrestore(ap->lock, flags);
3090 
3091 		ata_scsi_remove_dev(dev);
3092 	}
3093 
3094 	/* scan for new ones */
3095 	ata_scsi_scan_host(ap);
3096 
3097 	/* If we scanned while EH was in progress, scan would have
3098 	 * failed silently.  Requeue if there are enabled but
3099 	 * unattached devices.
3100 	 */
3101 	for (i = 0; i < ATA_MAX_DEVICES; i++) {
3102 		struct ata_device *dev = &ap->device[i];
3103 		if (ata_dev_enabled(dev) && !dev->sdev) {
3104 			queue_delayed_work(ata_aux_wq, &ap->hotplug_task,
3105 				round_jiffies_relative(HZ));
3106 			break;
3107 		}
3108 	}
3109 
3110 	DPRINTK("EXIT\n");
3111 }
3112 
3113 /**
3114  *	ata_scsi_user_scan - indication for user-initiated bus scan
3115  *	@shost: SCSI host to scan
3116  *	@channel: Channel to scan
3117  *	@id: ID to scan
3118  *	@lun: LUN to scan
3119  *
3120  *	This function is called when user explicitly requests bus
3121  *	scan.  Set probe pending flag and invoke EH.
3122  *
3123  *	LOCKING:
3124  *	SCSI layer (we don't care)
3125  *
3126  *	RETURNS:
3127  *	Zero.
3128  */
3129 static int ata_scsi_user_scan(struct Scsi_Host *shost, unsigned int channel,
3130 			      unsigned int id, unsigned int lun)
3131 {
3132 	struct ata_port *ap = ata_shost_to_port(shost);
3133 	unsigned long flags;
3134 	int rc = 0;
3135 
3136 	if (!ap->ops->error_handler)
3137 		return -EOPNOTSUPP;
3138 
3139 	if ((channel != SCAN_WILD_CARD && channel != 0) ||
3140 	    (lun != SCAN_WILD_CARD && lun != 0))
3141 		return -EINVAL;
3142 
3143 	spin_lock_irqsave(ap->lock, flags);
3144 
3145 	if (id == SCAN_WILD_CARD) {
3146 		ap->eh_info.probe_mask |= (1 << ATA_MAX_DEVICES) - 1;
3147 		ap->eh_info.action |= ATA_EH_SOFTRESET;
3148 	} else {
3149 		struct ata_device *dev = ata_find_dev(ap, id);
3150 
3151 		if (dev) {
3152 			ap->eh_info.probe_mask |= 1 << dev->devno;
3153 			ap->eh_info.action |= ATA_EH_SOFTRESET;
3154 			ap->eh_info.flags |= ATA_EHI_RESUME_LINK;
3155 		} else
3156 			rc = -EINVAL;
3157 	}
3158 
3159 	if (rc == 0) {
3160 		ata_port_schedule_eh(ap);
3161 		spin_unlock_irqrestore(ap->lock, flags);
3162 		ata_port_wait_eh(ap);
3163 	} else
3164 		spin_unlock_irqrestore(ap->lock, flags);
3165 
3166 	return rc;
3167 }
3168 
3169 /**
3170  *	ata_scsi_dev_rescan - initiate scsi_rescan_device()
3171  *	@work: Pointer to ATA port to perform scsi_rescan_device()
3172  *
3173  *	After ATA pass thru (SAT) commands are executed successfully,
3174  *	libata need to propagate the changes to SCSI layer.  This
3175  *	function must be executed from ata_aux_wq such that sdev
3176  *	attach/detach don't race with rescan.
3177  *
3178  *	LOCKING:
3179  *	Kernel thread context (may sleep).
3180  */
3181 void ata_scsi_dev_rescan(struct work_struct *work)
3182 {
3183 	struct ata_port *ap =
3184 		container_of(work, struct ata_port, scsi_rescan_task);
3185 	unsigned long flags;
3186 	unsigned int i;
3187 
3188 	spin_lock_irqsave(ap->lock, flags);
3189 
3190 	for (i = 0; i < ATA_MAX_DEVICES; i++) {
3191 		struct ata_device *dev = &ap->device[i];
3192 		struct scsi_device *sdev = dev->sdev;
3193 
3194 		if (!ata_dev_enabled(dev) || !sdev)
3195 			continue;
3196 		if (scsi_device_get(sdev))
3197 			continue;
3198 
3199 		spin_unlock_irqrestore(ap->lock, flags);
3200 		scsi_rescan_device(&(sdev->sdev_gendev));
3201 		scsi_device_put(sdev);
3202 		spin_lock_irqsave(ap->lock, flags);
3203 	}
3204 
3205 	spin_unlock_irqrestore(ap->lock, flags);
3206 }
3207 
3208 /**
3209  *	ata_sas_port_alloc - Allocate port for a SAS attached SATA device
3210  *	@host: ATA host container for all SAS ports
3211  *	@port_info: Information from low-level host driver
3212  *	@shost: SCSI host that the scsi device is attached to
3213  *
3214  *	LOCKING:
3215  *	PCI/etc. bus probe sem.
3216  *
3217  *	RETURNS:
3218  *	ata_port pointer on success / NULL on failure.
3219  */
3220 
3221 struct ata_port *ata_sas_port_alloc(struct ata_host *host,
3222 				    struct ata_port_info *port_info,
3223 				    struct Scsi_Host *shost)
3224 {
3225 	struct ata_port *ap = kzalloc(sizeof(*ap), GFP_KERNEL);
3226 	struct ata_probe_ent *ent;
3227 
3228 	if (!ap)
3229 		return NULL;
3230 
3231 	ent = ata_probe_ent_alloc(host->dev, port_info);
3232 	if (!ent) {
3233 		kfree(ap);
3234 		return NULL;
3235 	}
3236 
3237 	ata_port_init(ap, host, ent, 0);
3238 	ap->lock = shost->host_lock;
3239 	devm_kfree(host->dev, ent);
3240 	return ap;
3241 }
3242 EXPORT_SYMBOL_GPL(ata_sas_port_alloc);
3243 
3244 /**
3245  *	ata_sas_port_start - Set port up for dma.
3246  *	@ap: Port to initialize
3247  *
3248  *	Called just after data structures for each port are
3249  *	initialized.  Allocates DMA pad.
3250  *
3251  *	May be used as the port_start() entry in ata_port_operations.
3252  *
3253  *	LOCKING:
3254  *	Inherited from caller.
3255  */
3256 int ata_sas_port_start(struct ata_port *ap)
3257 {
3258 	return ata_pad_alloc(ap, ap->dev);
3259 }
3260 EXPORT_SYMBOL_GPL(ata_sas_port_start);
3261 
3262 /**
3263  *	ata_port_stop - Undo ata_sas_port_start()
3264  *	@ap: Port to shut down
3265  *
3266  *	Frees the DMA pad.
3267  *
3268  *	May be used as the port_stop() entry in ata_port_operations.
3269  *
3270  *	LOCKING:
3271  *	Inherited from caller.
3272  */
3273 
3274 void ata_sas_port_stop(struct ata_port *ap)
3275 {
3276 	ata_pad_free(ap, ap->dev);
3277 }
3278 EXPORT_SYMBOL_GPL(ata_sas_port_stop);
3279 
3280 /**
3281  *	ata_sas_port_init - Initialize a SATA device
3282  *	@ap: SATA port to initialize
3283  *
3284  *	LOCKING:
3285  *	PCI/etc. bus probe sem.
3286  *
3287  *	RETURNS:
3288  *	Zero on success, non-zero on error.
3289  */
3290 
3291 int ata_sas_port_init(struct ata_port *ap)
3292 {
3293 	int rc = ap->ops->port_start(ap);
3294 
3295 	if (!rc)
3296 		rc = ata_bus_probe(ap);
3297 
3298 	return rc;
3299 }
3300 EXPORT_SYMBOL_GPL(ata_sas_port_init);
3301 
3302 /**
3303  *	ata_sas_port_destroy - Destroy a SATA port allocated by ata_sas_port_alloc
3304  *	@ap: SATA port to destroy
3305  *
3306  */
3307 
3308 void ata_sas_port_destroy(struct ata_port *ap)
3309 {
3310 	if (ap->ops->port_stop)
3311 		ap->ops->port_stop(ap);
3312 	kfree(ap);
3313 }
3314 EXPORT_SYMBOL_GPL(ata_sas_port_destroy);
3315 
3316 /**
3317  *	ata_sas_slave_configure - Default slave_config routine for libata devices
3318  *	@sdev: SCSI device to configure
3319  *	@ap: ATA port to which SCSI device is attached
3320  *
3321  *	RETURNS:
3322  *	Zero.
3323  */
3324 
3325 int ata_sas_slave_configure(struct scsi_device *sdev, struct ata_port *ap)
3326 {
3327 	ata_scsi_sdev_config(sdev);
3328 	ata_scsi_dev_config(sdev, ap->device);
3329 	return 0;
3330 }
3331 EXPORT_SYMBOL_GPL(ata_sas_slave_configure);
3332 
3333 /**
3334  *	ata_sas_queuecmd - Issue SCSI cdb to libata-managed device
3335  *	@cmd: SCSI command to be sent
3336  *	@done: Completion function, called when command is complete
3337  *	@ap:	ATA port to which the command is being sent
3338  *
3339  *	RETURNS:
3340  *	Return value from __ata_scsi_queuecmd() if @cmd can be queued,
3341  *	0 otherwise.
3342  */
3343 
3344 int ata_sas_queuecmd(struct scsi_cmnd *cmd, void (*done)(struct scsi_cmnd *),
3345 		     struct ata_port *ap)
3346 {
3347 	int rc = 0;
3348 
3349 	ata_scsi_dump_cdb(ap, cmd);
3350 
3351 	if (likely(ata_scsi_dev_enabled(ap->device)))
3352 		rc = __ata_scsi_queuecmd(cmd, done, ap->device);
3353 	else {
3354 		cmd->result = (DID_BAD_TARGET << 16);
3355 		done(cmd);
3356 	}
3357 	return rc;
3358 }
3359 EXPORT_SYMBOL_GPL(ata_sas_queuecmd);
3360