xref: /openbmc/linux/drivers/ata/libata-scsi.c (revision 6ffa01d88c9dd45e2ed917b5eeeb494d07efb1ab)
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 #ifdef CONFIG_PM
514 /**
515  *	ata_scsi_device_suspend - suspend ATA device associated with sdev
516  *	@sdev: the SCSI device to suspend
517  *	@mesg: target power management message
518  *
519  *	Request suspend EH action on the ATA device associated with
520  *	@sdev and wait for the operation to complete.
521  *
522  *	LOCKING:
523  *	Kernel thread context (may sleep).
524  *
525  *	RETURNS:
526  *	0 on success, -errno otherwise.
527  */
528 int ata_scsi_device_suspend(struct scsi_device *sdev, pm_message_t mesg)
529 {
530 	struct ata_port *ap = ata_shost_to_port(sdev->host);
531 	struct ata_device *dev = ata_scsi_find_dev(ap, sdev);
532 	unsigned long flags;
533 	unsigned int action;
534 	int rc = 0;
535 
536 	if (!dev)
537 		goto out;
538 
539 	spin_lock_irqsave(ap->lock, flags);
540 
541 	/* wait for the previous resume to complete */
542 	while (dev->flags & ATA_DFLAG_SUSPENDED) {
543 		spin_unlock_irqrestore(ap->lock, flags);
544 		ata_port_wait_eh(ap);
545 		spin_lock_irqsave(ap->lock, flags);
546 	}
547 
548 	/* if @sdev is already detached, nothing to do */
549 	if (sdev->sdev_state == SDEV_OFFLINE ||
550 	    sdev->sdev_state == SDEV_CANCEL || sdev->sdev_state == SDEV_DEL)
551 		goto out_unlock;
552 
553 	/* request suspend */
554 	action = ATA_EH_SUSPEND;
555 	if (mesg.event != PM_EVENT_SUSPEND)
556 		action |= ATA_EH_PM_FREEZE;
557 	ap->eh_info.dev_action[dev->devno] |= action;
558 	ap->eh_info.flags |= ATA_EHI_QUIET;
559 	ata_port_schedule_eh(ap);
560 
561 	spin_unlock_irqrestore(ap->lock, flags);
562 
563 	/* wait for EH to do the job */
564 	ata_port_wait_eh(ap);
565 
566 	spin_lock_irqsave(ap->lock, flags);
567 
568 	/* If @sdev is still attached but the associated ATA device
569 	 * isn't suspended, the operation failed.
570 	 */
571 	if (sdev->sdev_state != SDEV_OFFLINE &&
572 	    sdev->sdev_state != SDEV_CANCEL && sdev->sdev_state != SDEV_DEL &&
573 	    !(dev->flags & ATA_DFLAG_SUSPENDED))
574 		rc = -EIO;
575 
576  out_unlock:
577 	spin_unlock_irqrestore(ap->lock, flags);
578  out:
579 	if (rc == 0)
580 		sdev->sdev_gendev.power.power_state = mesg;
581 	return rc;
582 }
583 
584 /**
585  *	ata_scsi_device_resume - resume ATA device associated with sdev
586  *	@sdev: the SCSI device to resume
587  *
588  *	Request resume EH action on the ATA device associated with
589  *	@sdev and return immediately.  This enables parallel
590  *	wakeup/spinup of devices.
591  *
592  *	LOCKING:
593  *	Kernel thread context (may sleep).
594  *
595  *	RETURNS:
596  *	0.
597  */
598 int ata_scsi_device_resume(struct scsi_device *sdev)
599 {
600 	struct ata_port *ap = ata_shost_to_port(sdev->host);
601 	struct ata_device *dev = ata_scsi_find_dev(ap, sdev);
602 	struct ata_eh_info *ehi = &ap->eh_info;
603 	unsigned long flags;
604 	unsigned int action;
605 
606 	if (!dev)
607 		goto out;
608 
609 	spin_lock_irqsave(ap->lock, flags);
610 
611 	/* if @sdev is already detached, nothing to do */
612 	if (sdev->sdev_state == SDEV_OFFLINE ||
613 	    sdev->sdev_state == SDEV_CANCEL || sdev->sdev_state == SDEV_DEL)
614 		goto out_unlock;
615 
616 	/* request resume */
617 	action = ATA_EH_RESUME;
618 	if (sdev->sdev_gendev.power.power_state.event == PM_EVENT_SUSPEND)
619 		__ata_ehi_hotplugged(ehi);
620 	else
621 		action |= ATA_EH_PM_FREEZE | ATA_EH_SOFTRESET;
622 	ehi->dev_action[dev->devno] |= action;
623 
624 	/* We don't want autopsy and verbose EH messages.  Disable
625 	 * those if we're the only device on this link.
626 	 */
627 	if (ata_port_max_devices(ap) == 1)
628 		ehi->flags |= ATA_EHI_NO_AUTOPSY | ATA_EHI_QUIET;
629 
630 	ata_port_schedule_eh(ap);
631 
632  out_unlock:
633 	spin_unlock_irqrestore(ap->lock, flags);
634  out:
635 	sdev->sdev_gendev.power.power_state = PMSG_ON;
636 	return 0;
637 }
638 #endif /* CONFIG_PM */
639 
640 /**
641  *	ata_to_sense_error - convert ATA error to SCSI error
642  *	@id: ATA device number
643  *	@drv_stat: value contained in ATA status register
644  *	@drv_err: value contained in ATA error register
645  *	@sk: the sense key we'll fill out
646  *	@asc: the additional sense code we'll fill out
647  *	@ascq: the additional sense code qualifier we'll fill out
648  *	@verbose: be verbose
649  *
650  *	Converts an ATA error into a SCSI error.  Fill out pointers to
651  *	SK, ASC, and ASCQ bytes for later use in fixed or descriptor
652  *	format sense blocks.
653  *
654  *	LOCKING:
655  *	spin_lock_irqsave(host lock)
656  */
657 static void ata_to_sense_error(unsigned id, u8 drv_stat, u8 drv_err, u8 *sk,
658 			       u8 *asc, u8 *ascq, int verbose)
659 {
660 	int i;
661 
662 	/* Based on the 3ware driver translation table */
663 	static const unsigned char sense_table[][4] = {
664 		/* BBD|ECC|ID|MAR */
665 		{0xd1, 		ABORTED_COMMAND, 0x00, 0x00}, 	// Device busy                  Aborted command
666 		/* BBD|ECC|ID */
667 		{0xd0,  	ABORTED_COMMAND, 0x00, 0x00}, 	// Device busy                  Aborted command
668 		/* ECC|MC|MARK */
669 		{0x61, 		HARDWARE_ERROR, 0x00, 0x00}, 	// Device fault                 Hardware error
670 		/* ICRC|ABRT */		/* NB: ICRC & !ABRT is BBD */
671 		{0x84, 		ABORTED_COMMAND, 0x47, 0x00}, 	// Data CRC error               SCSI parity error
672 		/* MC|ID|ABRT|TRK0|MARK */
673 		{0x37, 		NOT_READY, 0x04, 0x00}, 	// Unit offline                 Not ready
674 		/* MCR|MARK */
675 		{0x09, 		NOT_READY, 0x04, 0x00}, 	// Unrecovered disk error       Not ready
676 		/*  Bad address mark */
677 		{0x01, 		MEDIUM_ERROR, 0x13, 0x00}, 	// Address mark not found       Address mark not found for data field
678 		/* TRK0 */
679 		{0x02, 		HARDWARE_ERROR, 0x00, 0x00}, 	// Track 0 not found		  Hardware error
680 		/* Abort & !ICRC */
681 		{0x04, 		ABORTED_COMMAND, 0x00, 0x00}, 	// Aborted command              Aborted command
682 		/* Media change request */
683 		{0x08, 		NOT_READY, 0x04, 0x00}, 	// Media change request	  FIXME: faking offline
684 		/* SRV */
685 		{0x10, 		ABORTED_COMMAND, 0x14, 0x00}, 	// ID not found                 Recorded entity not found
686 		/* Media change */
687 		{0x08,  	NOT_READY, 0x04, 0x00}, 	// Media change		  FIXME: faking offline
688 		/* ECC */
689 		{0x40, 		MEDIUM_ERROR, 0x11, 0x04}, 	// Uncorrectable ECC error      Unrecovered read error
690 		/* BBD - block marked bad */
691 		{0x80, 		MEDIUM_ERROR, 0x11, 0x04}, 	// Block marked bad		  Medium error, unrecovered read error
692 		{0xFF, 0xFF, 0xFF, 0xFF}, // END mark
693 	};
694 	static const unsigned char stat_table[][4] = {
695 		/* Must be first because BUSY means no other bits valid */
696 		{0x80, 		ABORTED_COMMAND, 0x47, 0x00},	// Busy, fake parity for now
697 		{0x20, 		HARDWARE_ERROR,  0x00, 0x00}, 	// Device fault
698 		{0x08, 		ABORTED_COMMAND, 0x47, 0x00},	// Timed out in xfer, fake parity for now
699 		{0x04, 		RECOVERED_ERROR, 0x11, 0x00},	// Recovered ECC error	  Medium error, recovered
700 		{0xFF, 0xFF, 0xFF, 0xFF}, // END mark
701 	};
702 
703 	/*
704 	 *	Is this an error we can process/parse
705 	 */
706 	if (drv_stat & ATA_BUSY) {
707 		drv_err = 0;	/* Ignore the err bits, they're invalid */
708 	}
709 
710 	if (drv_err) {
711 		/* Look for drv_err */
712 		for (i = 0; sense_table[i][0] != 0xFF; i++) {
713 			/* Look for best matches first */
714 			if ((sense_table[i][0] & drv_err) ==
715 			    sense_table[i][0]) {
716 				*sk = sense_table[i][1];
717 				*asc = sense_table[i][2];
718 				*ascq = sense_table[i][3];
719 				goto translate_done;
720 			}
721 		}
722 		/* No immediate match */
723 		if (verbose)
724 			printk(KERN_WARNING "ata%u: no sense translation for "
725 			       "error 0x%02x\n", id, drv_err);
726 	}
727 
728 	/* Fall back to interpreting status bits */
729 	for (i = 0; stat_table[i][0] != 0xFF; i++) {
730 		if (stat_table[i][0] & drv_stat) {
731 			*sk = stat_table[i][1];
732 			*asc = stat_table[i][2];
733 			*ascq = stat_table[i][3];
734 			goto translate_done;
735 		}
736 	}
737 	/* No error?  Undecoded? */
738 	if (verbose)
739 		printk(KERN_WARNING "ata%u: no sense translation for "
740 		       "status: 0x%02x\n", id, drv_stat);
741 
742 	/* We need a sensible error return here, which is tricky, and one
743 	   that won't cause people to do things like return a disk wrongly */
744 	*sk = ABORTED_COMMAND;
745 	*asc = 0x00;
746 	*ascq = 0x00;
747 
748  translate_done:
749 	if (verbose)
750 		printk(KERN_ERR "ata%u: translated ATA stat/err 0x%02x/%02x "
751 		       "to SCSI SK/ASC/ASCQ 0x%x/%02x/%02x\n",
752 		       id, drv_stat, drv_err, *sk, *asc, *ascq);
753 	return;
754 }
755 
756 /*
757  *	ata_gen_passthru_sense - Generate check condition sense block.
758  *	@qc: Command that completed.
759  *
760  *	This function is specific to the ATA descriptor format sense
761  *	block specified for the ATA pass through commands.  Regardless
762  *	of whether the command errored or not, return a sense
763  *	block. Copy all controller registers into the sense
764  *	block. Clear sense key, ASC & ASCQ if there is no error.
765  *
766  *	LOCKING:
767  *	None.
768  */
769 static void ata_gen_passthru_sense(struct ata_queued_cmd *qc)
770 {
771 	struct scsi_cmnd *cmd = qc->scsicmd;
772 	struct ata_taskfile *tf = &qc->result_tf;
773 	unsigned char *sb = cmd->sense_buffer;
774 	unsigned char *desc = sb + 8;
775 	int verbose = qc->ap->ops->error_handler == NULL;
776 
777 	memset(sb, 0, SCSI_SENSE_BUFFERSIZE);
778 
779 	cmd->result = (DRIVER_SENSE << 24) | SAM_STAT_CHECK_CONDITION;
780 
781 	/*
782 	 * Use ata_to_sense_error() to map status register bits
783 	 * onto sense key, asc & ascq.
784 	 */
785 	if (qc->err_mask ||
786 	    tf->command & (ATA_BUSY | ATA_DF | ATA_ERR | ATA_DRQ)) {
787 		ata_to_sense_error(qc->ap->print_id, tf->command, tf->feature,
788 				   &sb[1], &sb[2], &sb[3], verbose);
789 		sb[1] &= 0x0f;
790 	}
791 
792 	/*
793 	 * Sense data is current and format is descriptor.
794 	 */
795 	sb[0] = 0x72;
796 
797 	desc[0] = 0x09;
798 
799 	/* set length of additional sense data */
800 	sb[7] = 14;
801 	desc[1] = 12;
802 
803 	/*
804 	 * Copy registers into sense buffer.
805 	 */
806 	desc[2] = 0x00;
807 	desc[3] = tf->feature;	/* == error reg */
808 	desc[5] = tf->nsect;
809 	desc[7] = tf->lbal;
810 	desc[9] = tf->lbam;
811 	desc[11] = tf->lbah;
812 	desc[12] = tf->device;
813 	desc[13] = tf->command; /* == status reg */
814 
815 	/*
816 	 * Fill in Extend bit, and the high order bytes
817 	 * if applicable.
818 	 */
819 	if (tf->flags & ATA_TFLAG_LBA48) {
820 		desc[2] |= 0x01;
821 		desc[4] = tf->hob_nsect;
822 		desc[6] = tf->hob_lbal;
823 		desc[8] = tf->hob_lbam;
824 		desc[10] = tf->hob_lbah;
825 	}
826 }
827 
828 /**
829  *	ata_gen_ata_sense - generate a SCSI fixed sense block
830  *	@qc: Command that we are erroring out
831  *
832  *	Generate sense block for a failed ATA command @qc.  Descriptor
833  *	format is used to accomodate LBA48 block address.
834  *
835  *	LOCKING:
836  *	None.
837  */
838 static void ata_gen_ata_sense(struct ata_queued_cmd *qc)
839 {
840 	struct ata_device *dev = qc->dev;
841 	struct scsi_cmnd *cmd = qc->scsicmd;
842 	struct ata_taskfile *tf = &qc->result_tf;
843 	unsigned char *sb = cmd->sense_buffer;
844 	unsigned char *desc = sb + 8;
845 	int verbose = qc->ap->ops->error_handler == NULL;
846 	u64 block;
847 
848 	memset(sb, 0, SCSI_SENSE_BUFFERSIZE);
849 
850 	cmd->result = (DRIVER_SENSE << 24) | SAM_STAT_CHECK_CONDITION;
851 
852 	/* sense data is current and format is descriptor */
853 	sb[0] = 0x72;
854 
855 	/* Use ata_to_sense_error() to map status register bits
856 	 * onto sense key, asc & ascq.
857 	 */
858 	if (qc->err_mask ||
859 	    tf->command & (ATA_BUSY | ATA_DF | ATA_ERR | ATA_DRQ)) {
860 		ata_to_sense_error(qc->ap->print_id, tf->command, tf->feature,
861 				   &sb[1], &sb[2], &sb[3], verbose);
862 		sb[1] &= 0x0f;
863 	}
864 
865 	block = ata_tf_read_block(&qc->result_tf, dev);
866 
867 	/* information sense data descriptor */
868 	sb[7] = 12;
869 	desc[0] = 0x00;
870 	desc[1] = 10;
871 
872 	desc[2] |= 0x80;	/* valid */
873 	desc[6] = block >> 40;
874 	desc[7] = block >> 32;
875 	desc[8] = block >> 24;
876 	desc[9] = block >> 16;
877 	desc[10] = block >> 8;
878 	desc[11] = block;
879 }
880 
881 static void ata_scsi_sdev_config(struct scsi_device *sdev)
882 {
883 	sdev->use_10_for_rw = 1;
884 	sdev->use_10_for_ms = 1;
885 }
886 
887 static void ata_scsi_dev_config(struct scsi_device *sdev,
888 				struct ata_device *dev)
889 {
890 	/* configure max sectors */
891 	blk_queue_max_sectors(sdev->request_queue, dev->max_sectors);
892 
893 	/* SATA DMA transfers must be multiples of 4 byte, so
894 	 * we need to pad ATAPI transfers using an extra sg.
895 	 * Decrement max hw segments accordingly.
896 	 */
897 	if (dev->class == ATA_DEV_ATAPI) {
898 		request_queue_t *q = sdev->request_queue;
899 		blk_queue_max_hw_segments(q, q->max_hw_segments - 1);
900 	}
901 
902 	if (dev->flags & ATA_DFLAG_NCQ) {
903 		int depth;
904 
905 		depth = min(sdev->host->can_queue, ata_id_queue_depth(dev->id));
906 		depth = min(ATA_MAX_QUEUE - 1, depth);
907 		scsi_adjust_queue_depth(sdev, MSG_SIMPLE_TAG, depth);
908 	}
909 }
910 
911 /**
912  *	ata_scsi_slave_config - Set SCSI device attributes
913  *	@sdev: SCSI device to examine
914  *
915  *	This is called before we actually start reading
916  *	and writing to the device, to configure certain
917  *	SCSI mid-layer behaviors.
918  *
919  *	LOCKING:
920  *	Defined by SCSI layer.  We don't really care.
921  */
922 
923 int ata_scsi_slave_config(struct scsi_device *sdev)
924 {
925 	struct ata_port *ap = ata_shost_to_port(sdev->host);
926 	struct ata_device *dev = __ata_scsi_find_dev(ap, sdev);
927 
928 	ata_scsi_sdev_config(sdev);
929 
930 	blk_queue_max_phys_segments(sdev->request_queue, LIBATA_MAX_PRD);
931 
932 	if (dev)
933 		ata_scsi_dev_config(sdev, dev);
934 
935 	return 0;	/* scsi layer doesn't check return value, sigh */
936 }
937 
938 /**
939  *	ata_scsi_slave_destroy - SCSI device is about to be destroyed
940  *	@sdev: SCSI device to be destroyed
941  *
942  *	@sdev is about to be destroyed for hot/warm unplugging.  If
943  *	this unplugging was initiated by libata as indicated by NULL
944  *	dev->sdev, this function doesn't have to do anything.
945  *	Otherwise, SCSI layer initiated warm-unplug is in progress.
946  *	Clear dev->sdev, schedule the device for ATA detach and invoke
947  *	EH.
948  *
949  *	LOCKING:
950  *	Defined by SCSI layer.  We don't really care.
951  */
952 void ata_scsi_slave_destroy(struct scsi_device *sdev)
953 {
954 	struct ata_port *ap = ata_shost_to_port(sdev->host);
955 	unsigned long flags;
956 	struct ata_device *dev;
957 
958 	if (!ap->ops->error_handler)
959 		return;
960 
961 	spin_lock_irqsave(ap->lock, flags);
962 	dev = __ata_scsi_find_dev(ap, sdev);
963 	if (dev && dev->sdev) {
964 		/* SCSI device already in CANCEL state, no need to offline it */
965 		dev->sdev = NULL;
966 		dev->flags |= ATA_DFLAG_DETACH;
967 		ata_port_schedule_eh(ap);
968 	}
969 	spin_unlock_irqrestore(ap->lock, flags);
970 }
971 
972 /**
973  *	ata_scsi_change_queue_depth - SCSI callback for queue depth config
974  *	@sdev: SCSI device to configure queue depth for
975  *	@queue_depth: new queue depth
976  *
977  *	This is libata standard hostt->change_queue_depth callback.
978  *	SCSI will call into this callback when user tries to set queue
979  *	depth via sysfs.
980  *
981  *	LOCKING:
982  *	SCSI layer (we don't care)
983  *
984  *	RETURNS:
985  *	Newly configured queue depth.
986  */
987 int ata_scsi_change_queue_depth(struct scsi_device *sdev, int queue_depth)
988 {
989 	struct ata_port *ap = ata_shost_to_port(sdev->host);
990 	struct ata_device *dev;
991 	unsigned long flags;
992 
993 	if (queue_depth < 1 || queue_depth == sdev->queue_depth)
994 		return sdev->queue_depth;
995 
996 	dev = ata_scsi_find_dev(ap, sdev);
997 	if (!dev || !ata_dev_enabled(dev))
998 		return sdev->queue_depth;
999 
1000 	/* NCQ enabled? */
1001 	spin_lock_irqsave(ap->lock, flags);
1002 	dev->flags &= ~ATA_DFLAG_NCQ_OFF;
1003 	if (queue_depth == 1 || !ata_ncq_enabled(dev)) {
1004 		dev->flags |= ATA_DFLAG_NCQ_OFF;
1005 		queue_depth = 1;
1006 	}
1007 	spin_unlock_irqrestore(ap->lock, flags);
1008 
1009 	/* limit and apply queue depth */
1010 	queue_depth = min(queue_depth, sdev->host->can_queue);
1011 	queue_depth = min(queue_depth, ata_id_queue_depth(dev->id));
1012 	queue_depth = min(queue_depth, ATA_MAX_QUEUE - 1);
1013 
1014 	if (sdev->queue_depth == queue_depth)
1015 		return -EINVAL;
1016 
1017 	scsi_adjust_queue_depth(sdev, MSG_SIMPLE_TAG, queue_depth);
1018 	return queue_depth;
1019 }
1020 
1021 /**
1022  *	ata_scsi_start_stop_xlat - Translate SCSI START STOP UNIT command
1023  *	@qc: Storage for translated ATA taskfile
1024  *
1025  *	Sets up an ATA taskfile to issue STANDBY (to stop) or READ VERIFY
1026  *	(to start). Perhaps these commands should be preceded by
1027  *	CHECK POWER MODE to see what power mode the device is already in.
1028  *	[See SAT revision 5 at www.t10.org]
1029  *
1030  *	LOCKING:
1031  *	spin_lock_irqsave(host lock)
1032  *
1033  *	RETURNS:
1034  *	Zero on success, non-zero on error.
1035  */
1036 static unsigned int ata_scsi_start_stop_xlat(struct ata_queued_cmd *qc)
1037 {
1038 	struct scsi_cmnd *scmd = qc->scsicmd;
1039 	struct ata_taskfile *tf = &qc->tf;
1040 	const u8 *cdb = scmd->cmnd;
1041 
1042 	if (scmd->cmd_len < 5)
1043 		goto invalid_fld;
1044 
1045 	tf->flags |= ATA_TFLAG_DEVICE | ATA_TFLAG_ISADDR;
1046 	tf->protocol = ATA_PROT_NODATA;
1047 	if (cdb[1] & 0x1) {
1048 		;	/* ignore IMMED bit, violates sat-r05 */
1049 	}
1050 	if (cdb[4] & 0x2)
1051 		goto invalid_fld;       /* LOEJ bit set not supported */
1052 	if (((cdb[4] >> 4) & 0xf) != 0)
1053 		goto invalid_fld;       /* power conditions not supported */
1054 	if (cdb[4] & 0x1) {
1055 		tf->nsect = 1;	/* 1 sector, lba=0 */
1056 
1057 		if (qc->dev->flags & ATA_DFLAG_LBA) {
1058 			tf->flags |= ATA_TFLAG_LBA;
1059 
1060 			tf->lbah = 0x0;
1061 			tf->lbam = 0x0;
1062 			tf->lbal = 0x0;
1063 			tf->device |= ATA_LBA;
1064 		} else {
1065 			/* CHS */
1066 			tf->lbal = 0x1; /* sect */
1067 			tf->lbam = 0x0; /* cyl low */
1068 			tf->lbah = 0x0; /* cyl high */
1069 		}
1070 
1071 		tf->command = ATA_CMD_VERIFY;	/* READ VERIFY */
1072 	} else
1073 		/* Issue ATA STANDBY IMMEDIATE command */
1074 		tf->command = ATA_CMD_STANDBYNOW1;
1075 
1076 	/*
1077 	 * Standby and Idle condition timers could be implemented but that
1078 	 * would require libata to implement the Power condition mode page
1079 	 * and allow the user to change it. Changing mode pages requires
1080 	 * MODE SELECT to be implemented.
1081 	 */
1082 
1083 	return 0;
1084 
1085 invalid_fld:
1086 	ata_scsi_set_sense(scmd, ILLEGAL_REQUEST, 0x24, 0x0);
1087 	/* "Invalid field in cbd" */
1088 	return 1;
1089 }
1090 
1091 
1092 /**
1093  *	ata_scsi_flush_xlat - Translate SCSI SYNCHRONIZE CACHE command
1094  *	@qc: Storage for translated ATA taskfile
1095  *
1096  *	Sets up an ATA taskfile to issue FLUSH CACHE or
1097  *	FLUSH CACHE EXT.
1098  *
1099  *	LOCKING:
1100  *	spin_lock_irqsave(host lock)
1101  *
1102  *	RETURNS:
1103  *	Zero on success, non-zero on error.
1104  */
1105 static unsigned int ata_scsi_flush_xlat(struct ata_queued_cmd *qc)
1106 {
1107 	struct ata_taskfile *tf = &qc->tf;
1108 
1109 	tf->flags |= ATA_TFLAG_DEVICE;
1110 	tf->protocol = ATA_PROT_NODATA;
1111 
1112 	if (qc->dev->flags & ATA_DFLAG_FLUSH_EXT)
1113 		tf->command = ATA_CMD_FLUSH_EXT;
1114 	else
1115 		tf->command = ATA_CMD_FLUSH;
1116 
1117 	return 0;
1118 }
1119 
1120 /**
1121  *	scsi_6_lba_len - Get LBA and transfer length
1122  *	@cdb: SCSI command to translate
1123  *
1124  *	Calculate LBA and transfer length for 6-byte commands.
1125  *
1126  *	RETURNS:
1127  *	@plba: the LBA
1128  *	@plen: the transfer length
1129  */
1130 static void scsi_6_lba_len(const u8 *cdb, u64 *plba, u32 *plen)
1131 {
1132 	u64 lba = 0;
1133 	u32 len = 0;
1134 
1135 	VPRINTK("six-byte command\n");
1136 
1137 	lba |= ((u64)cdb[2]) << 8;
1138 	lba |= ((u64)cdb[3]);
1139 
1140 	len |= ((u32)cdb[4]);
1141 
1142 	*plba = lba;
1143 	*plen = len;
1144 }
1145 
1146 /**
1147  *	scsi_10_lba_len - Get LBA and transfer length
1148  *	@cdb: SCSI command to translate
1149  *
1150  *	Calculate LBA and transfer length for 10-byte commands.
1151  *
1152  *	RETURNS:
1153  *	@plba: the LBA
1154  *	@plen: the transfer length
1155  */
1156 static void scsi_10_lba_len(const u8 *cdb, u64 *plba, u32 *plen)
1157 {
1158 	u64 lba = 0;
1159 	u32 len = 0;
1160 
1161 	VPRINTK("ten-byte command\n");
1162 
1163 	lba |= ((u64)cdb[2]) << 24;
1164 	lba |= ((u64)cdb[3]) << 16;
1165 	lba |= ((u64)cdb[4]) << 8;
1166 	lba |= ((u64)cdb[5]);
1167 
1168 	len |= ((u32)cdb[7]) << 8;
1169 	len |= ((u32)cdb[8]);
1170 
1171 	*plba = lba;
1172 	*plen = len;
1173 }
1174 
1175 /**
1176  *	scsi_16_lba_len - Get LBA and transfer length
1177  *	@cdb: SCSI command to translate
1178  *
1179  *	Calculate LBA and transfer length for 16-byte commands.
1180  *
1181  *	RETURNS:
1182  *	@plba: the LBA
1183  *	@plen: the transfer length
1184  */
1185 static void scsi_16_lba_len(const u8 *cdb, u64 *plba, u32 *plen)
1186 {
1187 	u64 lba = 0;
1188 	u32 len = 0;
1189 
1190 	VPRINTK("sixteen-byte command\n");
1191 
1192 	lba |= ((u64)cdb[2]) << 56;
1193 	lba |= ((u64)cdb[3]) << 48;
1194 	lba |= ((u64)cdb[4]) << 40;
1195 	lba |= ((u64)cdb[5]) << 32;
1196 	lba |= ((u64)cdb[6]) << 24;
1197 	lba |= ((u64)cdb[7]) << 16;
1198 	lba |= ((u64)cdb[8]) << 8;
1199 	lba |= ((u64)cdb[9]);
1200 
1201 	len |= ((u32)cdb[10]) << 24;
1202 	len |= ((u32)cdb[11]) << 16;
1203 	len |= ((u32)cdb[12]) << 8;
1204 	len |= ((u32)cdb[13]);
1205 
1206 	*plba = lba;
1207 	*plen = len;
1208 }
1209 
1210 /**
1211  *	ata_scsi_verify_xlat - Translate SCSI VERIFY command into an ATA one
1212  *	@qc: Storage for translated ATA taskfile
1213  *
1214  *	Converts SCSI VERIFY command to an ATA READ VERIFY command.
1215  *
1216  *	LOCKING:
1217  *	spin_lock_irqsave(host lock)
1218  *
1219  *	RETURNS:
1220  *	Zero on success, non-zero on error.
1221  */
1222 static unsigned int ata_scsi_verify_xlat(struct ata_queued_cmd *qc)
1223 {
1224 	struct scsi_cmnd *scmd = qc->scsicmd;
1225 	struct ata_taskfile *tf = &qc->tf;
1226 	struct ata_device *dev = qc->dev;
1227 	u64 dev_sectors = qc->dev->n_sectors;
1228 	const u8 *cdb = scmd->cmnd;
1229 	u64 block;
1230 	u32 n_block;
1231 
1232 	tf->flags |= ATA_TFLAG_ISADDR | ATA_TFLAG_DEVICE;
1233 	tf->protocol = ATA_PROT_NODATA;
1234 
1235 	if (cdb[0] == VERIFY) {
1236 		if (scmd->cmd_len < 10)
1237 			goto invalid_fld;
1238 		scsi_10_lba_len(cdb, &block, &n_block);
1239 	} else if (cdb[0] == VERIFY_16) {
1240 		if (scmd->cmd_len < 16)
1241 			goto invalid_fld;
1242 		scsi_16_lba_len(cdb, &block, &n_block);
1243 	} else
1244 		goto invalid_fld;
1245 
1246 	if (!n_block)
1247 		goto nothing_to_do;
1248 	if (block >= dev_sectors)
1249 		goto out_of_range;
1250 	if ((block + n_block) > dev_sectors)
1251 		goto out_of_range;
1252 
1253 	if (dev->flags & ATA_DFLAG_LBA) {
1254 		tf->flags |= ATA_TFLAG_LBA;
1255 
1256 		if (lba_28_ok(block, n_block)) {
1257 			/* use LBA28 */
1258 			tf->command = ATA_CMD_VERIFY;
1259 			tf->device |= (block >> 24) & 0xf;
1260 		} else if (lba_48_ok(block, n_block)) {
1261 			if (!(dev->flags & ATA_DFLAG_LBA48))
1262 				goto out_of_range;
1263 
1264 			/* use LBA48 */
1265 			tf->flags |= ATA_TFLAG_LBA48;
1266 			tf->command = ATA_CMD_VERIFY_EXT;
1267 
1268 			tf->hob_nsect = (n_block >> 8) & 0xff;
1269 
1270 			tf->hob_lbah = (block >> 40) & 0xff;
1271 			tf->hob_lbam = (block >> 32) & 0xff;
1272 			tf->hob_lbal = (block >> 24) & 0xff;
1273 		} else
1274 			/* request too large even for LBA48 */
1275 			goto out_of_range;
1276 
1277 		tf->nsect = n_block & 0xff;
1278 
1279 		tf->lbah = (block >> 16) & 0xff;
1280 		tf->lbam = (block >> 8) & 0xff;
1281 		tf->lbal = block & 0xff;
1282 
1283 		tf->device |= ATA_LBA;
1284 	} else {
1285 		/* CHS */
1286 		u32 sect, head, cyl, track;
1287 
1288 		if (!lba_28_ok(block, n_block))
1289 			goto out_of_range;
1290 
1291 		/* Convert LBA to CHS */
1292 		track = (u32)block / dev->sectors;
1293 		cyl   = track / dev->heads;
1294 		head  = track % dev->heads;
1295 		sect  = (u32)block % dev->sectors + 1;
1296 
1297 		DPRINTK("block %u track %u cyl %u head %u sect %u\n",
1298 			(u32)block, track, cyl, head, sect);
1299 
1300 		/* Check whether the converted CHS can fit.
1301 		   Cylinder: 0-65535
1302 		   Head: 0-15
1303 		   Sector: 1-255*/
1304 		if ((cyl >> 16) || (head >> 4) || (sect >> 8) || (!sect))
1305 			goto out_of_range;
1306 
1307 		tf->command = ATA_CMD_VERIFY;
1308 		tf->nsect = n_block & 0xff; /* Sector count 0 means 256 sectors */
1309 		tf->lbal = sect;
1310 		tf->lbam = cyl;
1311 		tf->lbah = cyl >> 8;
1312 		tf->device |= head;
1313 	}
1314 
1315 	return 0;
1316 
1317 invalid_fld:
1318 	ata_scsi_set_sense(scmd, ILLEGAL_REQUEST, 0x24, 0x0);
1319 	/* "Invalid field in cbd" */
1320 	return 1;
1321 
1322 out_of_range:
1323 	ata_scsi_set_sense(scmd, ILLEGAL_REQUEST, 0x21, 0x0);
1324 	/* "Logical Block Address out of range" */
1325 	return 1;
1326 
1327 nothing_to_do:
1328 	scmd->result = SAM_STAT_GOOD;
1329 	return 1;
1330 }
1331 
1332 /**
1333  *	ata_scsi_rw_xlat - Translate SCSI r/w command into an ATA one
1334  *	@qc: Storage for translated ATA taskfile
1335  *
1336  *	Converts any of six SCSI read/write commands into the
1337  *	ATA counterpart, including starting sector (LBA),
1338  *	sector count, and taking into account the device's LBA48
1339  *	support.
1340  *
1341  *	Commands %READ_6, %READ_10, %READ_16, %WRITE_6, %WRITE_10, and
1342  *	%WRITE_16 are currently supported.
1343  *
1344  *	LOCKING:
1345  *	spin_lock_irqsave(host lock)
1346  *
1347  *	RETURNS:
1348  *	Zero on success, non-zero on error.
1349  */
1350 static unsigned int ata_scsi_rw_xlat(struct ata_queued_cmd *qc)
1351 {
1352 	struct scsi_cmnd *scmd = qc->scsicmd;
1353 	const u8 *cdb = scmd->cmnd;
1354 	unsigned int tf_flags = 0;
1355 	u64 block;
1356 	u32 n_block;
1357 	int rc;
1358 
1359 	if (cdb[0] == WRITE_10 || cdb[0] == WRITE_6 || cdb[0] == WRITE_16)
1360 		tf_flags |= ATA_TFLAG_WRITE;
1361 
1362 	/* Calculate the SCSI LBA, transfer length and FUA. */
1363 	switch (cdb[0]) {
1364 	case READ_10:
1365 	case WRITE_10:
1366 		if (unlikely(scmd->cmd_len < 10))
1367 			goto invalid_fld;
1368 		scsi_10_lba_len(cdb, &block, &n_block);
1369 		if (unlikely(cdb[1] & (1 << 3)))
1370 			tf_flags |= ATA_TFLAG_FUA;
1371 		break;
1372 	case READ_6:
1373 	case WRITE_6:
1374 		if (unlikely(scmd->cmd_len < 6))
1375 			goto invalid_fld;
1376 		scsi_6_lba_len(cdb, &block, &n_block);
1377 
1378 		/* for 6-byte r/w commands, transfer length 0
1379 		 * means 256 blocks of data, not 0 block.
1380 		 */
1381 		if (!n_block)
1382 			n_block = 256;
1383 		break;
1384 	case READ_16:
1385 	case WRITE_16:
1386 		if (unlikely(scmd->cmd_len < 16))
1387 			goto invalid_fld;
1388 		scsi_16_lba_len(cdb, &block, &n_block);
1389 		if (unlikely(cdb[1] & (1 << 3)))
1390 			tf_flags |= ATA_TFLAG_FUA;
1391 		break;
1392 	default:
1393 		DPRINTK("no-byte command\n");
1394 		goto invalid_fld;
1395 	}
1396 
1397 	/* Check and compose ATA command */
1398 	if (!n_block)
1399 		/* For 10-byte and 16-byte SCSI R/W commands, transfer
1400 		 * length 0 means transfer 0 block of data.
1401 		 * However, for ATA R/W commands, sector count 0 means
1402 		 * 256 or 65536 sectors, not 0 sectors as in SCSI.
1403 		 *
1404 		 * WARNING: one or two older ATA drives treat 0 as 0...
1405 		 */
1406 		goto nothing_to_do;
1407 
1408 	qc->flags |= ATA_QCFLAG_IO;
1409 	qc->nbytes = n_block * ATA_SECT_SIZE;
1410 
1411 	rc = ata_build_rw_tf(&qc->tf, qc->dev, block, n_block, tf_flags,
1412 			     qc->tag);
1413 	if (likely(rc == 0))
1414 		return 0;
1415 
1416 	if (rc == -ERANGE)
1417 		goto out_of_range;
1418 	/* treat all other errors as -EINVAL, fall through */
1419 invalid_fld:
1420 	ata_scsi_set_sense(scmd, ILLEGAL_REQUEST, 0x24, 0x0);
1421 	/* "Invalid field in cbd" */
1422 	return 1;
1423 
1424 out_of_range:
1425 	ata_scsi_set_sense(scmd, ILLEGAL_REQUEST, 0x21, 0x0);
1426 	/* "Logical Block Address out of range" */
1427 	return 1;
1428 
1429 nothing_to_do:
1430 	scmd->result = SAM_STAT_GOOD;
1431 	return 1;
1432 }
1433 
1434 static void ata_scsi_qc_complete(struct ata_queued_cmd *qc)
1435 {
1436 	struct ata_port *ap = qc->ap;
1437 	struct scsi_cmnd *cmd = qc->scsicmd;
1438 	u8 *cdb = cmd->cmnd;
1439  	int need_sense = (qc->err_mask != 0);
1440 
1441 	/* We snoop the SET_FEATURES - Write Cache ON/OFF command, and
1442 	 * schedule EH_REVALIDATE operation to update the IDENTIFY DEVICE
1443 	 * cache
1444 	 */
1445 	if (ap->ops->error_handler &&
1446 	    !need_sense && (qc->tf.command == ATA_CMD_SET_FEATURES) &&
1447 	    ((qc->tf.feature == SETFEATURES_WC_ON) ||
1448 	     (qc->tf.feature == SETFEATURES_WC_OFF))) {
1449 		ap->eh_info.action |= ATA_EH_REVALIDATE;
1450 		ata_port_schedule_eh(ap);
1451 	}
1452 
1453 	/* For ATA pass thru (SAT) commands, generate a sense block if
1454 	 * user mandated it or if there's an error.  Note that if we
1455 	 * generate because the user forced us to, a check condition
1456 	 * is generated and the ATA register values are returned
1457 	 * whether the command completed successfully or not. If there
1458 	 * was no error, SK, ASC and ASCQ will all be zero.
1459 	 */
1460 	if (((cdb[0] == ATA_16) || (cdb[0] == ATA_12)) &&
1461  	    ((cdb[2] & 0x20) || need_sense)) {
1462 		ata_gen_passthru_sense(qc);
1463 	} else {
1464 		if (!need_sense) {
1465 			cmd->result = SAM_STAT_GOOD;
1466 		} else {
1467 			/* TODO: decide which descriptor format to use
1468 			 * for 48b LBA devices and call that here
1469 			 * instead of the fixed desc, which is only
1470 			 * good for smaller LBA (and maybe CHS?)
1471 			 * devices.
1472 			 */
1473 			ata_gen_ata_sense(qc);
1474 		}
1475 	}
1476 
1477 	if (need_sense && !ap->ops->error_handler)
1478 		ata_dump_status(ap->print_id, &qc->result_tf);
1479 
1480 	qc->scsidone(cmd);
1481 
1482 	ata_qc_free(qc);
1483 }
1484 
1485 /**
1486  *	ata_scmd_need_defer - Check whether we need to defer scmd
1487  *	@dev: ATA device to which the command is addressed
1488  *	@is_io: Is the command IO (and thus possibly NCQ)?
1489  *
1490  *	NCQ and non-NCQ commands cannot run together.  As upper layer
1491  *	only knows the queue depth, we are responsible for maintaining
1492  *	exclusion.  This function checks whether a new command can be
1493  *	issued to @dev.
1494  *
1495  *	LOCKING:
1496  *	spin_lock_irqsave(host lock)
1497  *
1498  *	RETURNS:
1499  *	1 if deferring is needed, 0 otherwise.
1500  */
1501 static int ata_scmd_need_defer(struct ata_device *dev, int is_io)
1502 {
1503 	struct ata_port *ap = dev->ap;
1504 	int is_ncq = is_io && ata_ncq_enabled(dev);
1505 
1506 	if (is_ncq) {
1507 		if (!ata_tag_valid(ap->active_tag))
1508 			return 0;
1509 	} else {
1510 		if (!ata_tag_valid(ap->active_tag) && !ap->sactive)
1511 			return 0;
1512 	}
1513 	return 1;
1514 }
1515 
1516 /**
1517  *	ata_scsi_translate - Translate then issue SCSI command to ATA device
1518  *	@dev: ATA device to which the command is addressed
1519  *	@cmd: SCSI command to execute
1520  *	@done: SCSI command completion function
1521  *	@xlat_func: Actor which translates @cmd to an ATA taskfile
1522  *
1523  *	Our ->queuecommand() function has decided that the SCSI
1524  *	command issued can be directly translated into an ATA
1525  *	command, rather than handled internally.
1526  *
1527  *	This function sets up an ata_queued_cmd structure for the
1528  *	SCSI command, and sends that ata_queued_cmd to the hardware.
1529  *
1530  *	The xlat_func argument (actor) returns 0 if ready to execute
1531  *	ATA command, else 1 to finish translation. If 1 is returned
1532  *	then cmd->result (and possibly cmd->sense_buffer) are assumed
1533  *	to be set reflecting an error condition or clean (early)
1534  *	termination.
1535  *
1536  *	LOCKING:
1537  *	spin_lock_irqsave(host lock)
1538  *
1539  *	RETURNS:
1540  *	0 on success, SCSI_ML_QUEUE_DEVICE_BUSY if the command
1541  *	needs to be deferred.
1542  */
1543 static int ata_scsi_translate(struct ata_device *dev, struct scsi_cmnd *cmd,
1544 			      void (*done)(struct scsi_cmnd *),
1545 			      ata_xlat_func_t xlat_func)
1546 {
1547 	struct ata_queued_cmd *qc;
1548 	int is_io = xlat_func == ata_scsi_rw_xlat;
1549 
1550 	VPRINTK("ENTER\n");
1551 
1552 	if (unlikely(ata_scmd_need_defer(dev, is_io)))
1553 		goto defer;
1554 
1555 	qc = ata_scsi_qc_new(dev, cmd, done);
1556 	if (!qc)
1557 		goto err_mem;
1558 
1559 	/* data is present; dma-map it */
1560 	if (cmd->sc_data_direction == DMA_FROM_DEVICE ||
1561 	    cmd->sc_data_direction == DMA_TO_DEVICE) {
1562 		if (unlikely(cmd->request_bufflen < 1)) {
1563 			ata_dev_printk(dev, KERN_WARNING,
1564 				       "WARNING: zero len r/w req\n");
1565 			goto err_did;
1566 		}
1567 
1568 		if (cmd->use_sg)
1569 			ata_sg_init(qc, cmd->request_buffer, cmd->use_sg);
1570 		else
1571 			ata_sg_init_one(qc, cmd->request_buffer,
1572 					cmd->request_bufflen);
1573 
1574 		qc->dma_dir = cmd->sc_data_direction;
1575 	}
1576 
1577 	qc->complete_fn = ata_scsi_qc_complete;
1578 
1579 	if (xlat_func(qc))
1580 		goto early_finish;
1581 
1582 	/* select device, send command to hardware */
1583 	ata_qc_issue(qc);
1584 
1585 	VPRINTK("EXIT\n");
1586 	return 0;
1587 
1588 early_finish:
1589         ata_qc_free(qc);
1590 	done(cmd);
1591 	DPRINTK("EXIT - early finish (good or error)\n");
1592 	return 0;
1593 
1594 err_did:
1595 	ata_qc_free(qc);
1596 	cmd->result = (DID_ERROR << 16);
1597 	done(cmd);
1598 err_mem:
1599 	DPRINTK("EXIT - internal\n");
1600 	return 0;
1601 
1602 defer:
1603 	DPRINTK("EXIT - defer\n");
1604 	return SCSI_MLQUEUE_DEVICE_BUSY;
1605 }
1606 
1607 /**
1608  *	ata_scsi_rbuf_get - Map response buffer.
1609  *	@cmd: SCSI command containing buffer to be mapped.
1610  *	@buf_out: Pointer to mapped area.
1611  *
1612  *	Maps buffer contained within SCSI command @cmd.
1613  *
1614  *	LOCKING:
1615  *	spin_lock_irqsave(host lock)
1616  *
1617  *	RETURNS:
1618  *	Length of response buffer.
1619  */
1620 
1621 static unsigned int ata_scsi_rbuf_get(struct scsi_cmnd *cmd, u8 **buf_out)
1622 {
1623 	u8 *buf;
1624 	unsigned int buflen;
1625 
1626 	if (cmd->use_sg) {
1627 		struct scatterlist *sg;
1628 
1629 		sg = (struct scatterlist *) cmd->request_buffer;
1630 		buf = kmap_atomic(sg->page, KM_IRQ0) + sg->offset;
1631 		buflen = sg->length;
1632 	} else {
1633 		buf = cmd->request_buffer;
1634 		buflen = cmd->request_bufflen;
1635 	}
1636 
1637 	*buf_out = buf;
1638 	return buflen;
1639 }
1640 
1641 /**
1642  *	ata_scsi_rbuf_put - Unmap response buffer.
1643  *	@cmd: SCSI command containing buffer to be unmapped.
1644  *	@buf: buffer to unmap
1645  *
1646  *	Unmaps response buffer contained within @cmd.
1647  *
1648  *	LOCKING:
1649  *	spin_lock_irqsave(host lock)
1650  */
1651 
1652 static inline void ata_scsi_rbuf_put(struct scsi_cmnd *cmd, u8 *buf)
1653 {
1654 	if (cmd->use_sg) {
1655 		struct scatterlist *sg;
1656 
1657 		sg = (struct scatterlist *) cmd->request_buffer;
1658 		kunmap_atomic(buf - sg->offset, KM_IRQ0);
1659 	}
1660 }
1661 
1662 /**
1663  *	ata_scsi_rbuf_fill - wrapper for SCSI command simulators
1664  *	@args: device IDENTIFY data / SCSI command of interest.
1665  *	@actor: Callback hook for desired SCSI command simulator
1666  *
1667  *	Takes care of the hard work of simulating a SCSI command...
1668  *	Mapping the response buffer, calling the command's handler,
1669  *	and handling the handler's return value.  This return value
1670  *	indicates whether the handler wishes the SCSI command to be
1671  *	completed successfully (0), or not (in which case cmd->result
1672  *	and sense buffer are assumed to be set).
1673  *
1674  *	LOCKING:
1675  *	spin_lock_irqsave(host lock)
1676  */
1677 
1678 void ata_scsi_rbuf_fill(struct ata_scsi_args *args,
1679 		        unsigned int (*actor) (struct ata_scsi_args *args,
1680 			     		   u8 *rbuf, unsigned int buflen))
1681 {
1682 	u8 *rbuf;
1683 	unsigned int buflen, rc;
1684 	struct scsi_cmnd *cmd = args->cmd;
1685 
1686 	buflen = ata_scsi_rbuf_get(cmd, &rbuf);
1687 	memset(rbuf, 0, buflen);
1688 	rc = actor(args, rbuf, buflen);
1689 	ata_scsi_rbuf_put(cmd, rbuf);
1690 
1691 	if (rc == 0)
1692 		cmd->result = SAM_STAT_GOOD;
1693 	args->done(cmd);
1694 }
1695 
1696 /**
1697  *	ATA_SCSI_RBUF_SET - helper to set values in SCSI response buffer
1698  *	@idx: byte index into SCSI response buffer
1699  *	@val: value to set
1700  *
1701  *	To be used by SCSI command simulator functions.  This macros
1702  *	expects two local variables, u8 *rbuf and unsigned int buflen,
1703  *	are in scope.
1704  *
1705  *	LOCKING:
1706  *	None.
1707  */
1708 #define ATA_SCSI_RBUF_SET(idx, val) do { \
1709 		if ((idx) < buflen) rbuf[(idx)] = (u8)(val); \
1710 	} while (0)
1711 
1712 /**
1713  *	ata_scsiop_inq_std - Simulate INQUIRY command
1714  *	@args: device IDENTIFY data / SCSI command of interest.
1715  *	@rbuf: Response buffer, to which simulated SCSI cmd output is sent.
1716  *	@buflen: Response buffer length.
1717  *
1718  *	Returns standard device identification data associated
1719  *	with non-VPD INQUIRY command output.
1720  *
1721  *	LOCKING:
1722  *	spin_lock_irqsave(host lock)
1723  */
1724 
1725 unsigned int ata_scsiop_inq_std(struct ata_scsi_args *args, u8 *rbuf,
1726 			       unsigned int buflen)
1727 {
1728 	u8 hdr[] = {
1729 		TYPE_DISK,
1730 		0,
1731 		0x5,	/* claim SPC-3 version compatibility */
1732 		2,
1733 		95 - 4
1734 	};
1735 
1736 	/* set scsi removeable (RMB) bit per ata bit */
1737 	if (ata_id_removeable(args->id))
1738 		hdr[1] |= (1 << 7);
1739 
1740 	VPRINTK("ENTER\n");
1741 
1742 	memcpy(rbuf, hdr, sizeof(hdr));
1743 
1744 	if (buflen > 35) {
1745 		memcpy(&rbuf[8], "ATA     ", 8);
1746 		ata_id_string(args->id, &rbuf[16], ATA_ID_PROD, 16);
1747 		ata_id_string(args->id, &rbuf[32], ATA_ID_FW_REV, 4);
1748 		if (rbuf[32] == 0 || rbuf[32] == ' ')
1749 			memcpy(&rbuf[32], "n/a ", 4);
1750 	}
1751 
1752 	if (buflen > 63) {
1753 		const u8 versions[] = {
1754 			0x60,	/* SAM-3 (no version claimed) */
1755 
1756 			0x03,
1757 			0x20,	/* SBC-2 (no version claimed) */
1758 
1759 			0x02,
1760 			0x60	/* SPC-3 (no version claimed) */
1761 		};
1762 
1763 		memcpy(rbuf + 59, versions, sizeof(versions));
1764 	}
1765 
1766 	return 0;
1767 }
1768 
1769 /**
1770  *	ata_scsiop_inq_00 - Simulate INQUIRY VPD page 0, list of pages
1771  *	@args: device IDENTIFY data / SCSI command of interest.
1772  *	@rbuf: Response buffer, to which simulated SCSI cmd output is sent.
1773  *	@buflen: Response buffer length.
1774  *
1775  *	Returns list of inquiry VPD pages available.
1776  *
1777  *	LOCKING:
1778  *	spin_lock_irqsave(host lock)
1779  */
1780 
1781 unsigned int ata_scsiop_inq_00(struct ata_scsi_args *args, u8 *rbuf,
1782 			      unsigned int buflen)
1783 {
1784 	const u8 pages[] = {
1785 		0x00,	/* page 0x00, this page */
1786 		0x80,	/* page 0x80, unit serial no page */
1787 		0x83	/* page 0x83, device ident page */
1788 	};
1789 	rbuf[3] = sizeof(pages);	/* number of supported VPD pages */
1790 
1791 	if (buflen > 6)
1792 		memcpy(rbuf + 4, pages, sizeof(pages));
1793 
1794 	return 0;
1795 }
1796 
1797 /**
1798  *	ata_scsiop_inq_80 - Simulate INQUIRY VPD page 80, device serial number
1799  *	@args: device IDENTIFY data / SCSI command of interest.
1800  *	@rbuf: Response buffer, to which simulated SCSI cmd output is sent.
1801  *	@buflen: Response buffer length.
1802  *
1803  *	Returns ATA device serial number.
1804  *
1805  *	LOCKING:
1806  *	spin_lock_irqsave(host lock)
1807  */
1808 
1809 unsigned int ata_scsiop_inq_80(struct ata_scsi_args *args, u8 *rbuf,
1810 			      unsigned int buflen)
1811 {
1812 	const u8 hdr[] = {
1813 		0,
1814 		0x80,			/* this page code */
1815 		0,
1816 		ATA_ID_SERNO_LEN,	/* page len */
1817 	};
1818 	memcpy(rbuf, hdr, sizeof(hdr));
1819 
1820 	if (buflen > (ATA_ID_SERNO_LEN + 4 - 1))
1821 		ata_id_string(args->id, (unsigned char *) &rbuf[4],
1822 			      ATA_ID_SERNO, ATA_ID_SERNO_LEN);
1823 
1824 	return 0;
1825 }
1826 
1827 /**
1828  *	ata_scsiop_inq_83 - Simulate INQUIRY VPD page 83, device identity
1829  *	@args: device IDENTIFY data / SCSI command of interest.
1830  *	@rbuf: Response buffer, to which simulated SCSI cmd output is sent.
1831  *	@buflen: Response buffer length.
1832  *
1833  *	Yields two logical unit device identification designators:
1834  *	 - vendor specific ASCII containing the ATA serial number
1835  *	 - SAT defined "t10 vendor id based" containing ASCII vendor
1836  *	   name ("ATA     "), model and serial numbers.
1837  *
1838  *	LOCKING:
1839  *	spin_lock_irqsave(host lock)
1840  */
1841 
1842 unsigned int ata_scsiop_inq_83(struct ata_scsi_args *args, u8 *rbuf,
1843 			      unsigned int buflen)
1844 {
1845 	int num;
1846 	const int sat_model_serial_desc_len = 68;
1847 
1848 	rbuf[1] = 0x83;			/* this page code */
1849 	num = 4;
1850 
1851 	if (buflen > (ATA_ID_SERNO_LEN + num + 3)) {
1852 		/* piv=0, assoc=lu, code_set=ACSII, designator=vendor */
1853 		rbuf[num + 0] = 2;
1854 		rbuf[num + 3] = ATA_ID_SERNO_LEN;
1855 		num += 4;
1856 		ata_id_string(args->id, (unsigned char *) rbuf + num,
1857 			      ATA_ID_SERNO, ATA_ID_SERNO_LEN);
1858 		num += ATA_ID_SERNO_LEN;
1859 	}
1860 	if (buflen > (sat_model_serial_desc_len + num + 3)) {
1861 		/* SAT defined lu model and serial numbers descriptor */
1862 		/* piv=0, assoc=lu, code_set=ACSII, designator=t10 vendor id */
1863 		rbuf[num + 0] = 2;
1864 		rbuf[num + 1] = 1;
1865 		rbuf[num + 3] = sat_model_serial_desc_len;
1866 		num += 4;
1867 		memcpy(rbuf + num, "ATA     ", 8);
1868 		num += 8;
1869 		ata_id_string(args->id, (unsigned char *) rbuf + num,
1870 			      ATA_ID_PROD, ATA_ID_PROD_LEN);
1871 		num += ATA_ID_PROD_LEN;
1872 		ata_id_string(args->id, (unsigned char *) rbuf + num,
1873 			      ATA_ID_SERNO, ATA_ID_SERNO_LEN);
1874 		num += ATA_ID_SERNO_LEN;
1875 	}
1876 	rbuf[3] = num - 4;    /* page len (assume less than 256 bytes) */
1877 	return 0;
1878 }
1879 
1880 /**
1881  *	ata_scsiop_noop - Command handler that simply returns success.
1882  *	@args: device IDENTIFY data / SCSI command of interest.
1883  *	@rbuf: Response buffer, to which simulated SCSI cmd output is sent.
1884  *	@buflen: Response buffer length.
1885  *
1886  *	No operation.  Simply returns success to caller, to indicate
1887  *	that the caller should successfully complete this SCSI command.
1888  *
1889  *	LOCKING:
1890  *	spin_lock_irqsave(host lock)
1891  */
1892 
1893 unsigned int ata_scsiop_noop(struct ata_scsi_args *args, u8 *rbuf,
1894 			    unsigned int buflen)
1895 {
1896 	VPRINTK("ENTER\n");
1897 	return 0;
1898 }
1899 
1900 /**
1901  *	ata_msense_push - Push data onto MODE SENSE data output buffer
1902  *	@ptr_io: (input/output) Location to store more output data
1903  *	@last: End of output data buffer
1904  *	@buf: Pointer to BLOB being added to output buffer
1905  *	@buflen: Length of BLOB
1906  *
1907  *	Store MODE SENSE data on an output buffer.
1908  *
1909  *	LOCKING:
1910  *	None.
1911  */
1912 
1913 static void ata_msense_push(u8 **ptr_io, const u8 *last,
1914 			    const u8 *buf, unsigned int buflen)
1915 {
1916 	u8 *ptr = *ptr_io;
1917 
1918 	if ((ptr + buflen - 1) > last)
1919 		return;
1920 
1921 	memcpy(ptr, buf, buflen);
1922 
1923 	ptr += buflen;
1924 
1925 	*ptr_io = ptr;
1926 }
1927 
1928 /**
1929  *	ata_msense_caching - Simulate MODE SENSE caching info page
1930  *	@id: device IDENTIFY data
1931  *	@ptr_io: (input/output) Location to store more output data
1932  *	@last: End of output data buffer
1933  *
1934  *	Generate a caching info page, which conditionally indicates
1935  *	write caching to the SCSI layer, depending on device
1936  *	capabilities.
1937  *
1938  *	LOCKING:
1939  *	None.
1940  */
1941 
1942 static unsigned int ata_msense_caching(u16 *id, u8 **ptr_io,
1943 				       const u8 *last)
1944 {
1945 	u8 page[CACHE_MPAGE_LEN];
1946 
1947 	memcpy(page, def_cache_mpage, sizeof(page));
1948 	if (ata_id_wcache_enabled(id))
1949 		page[2] |= (1 << 2);	/* write cache enable */
1950 	if (!ata_id_rahead_enabled(id))
1951 		page[12] |= (1 << 5);	/* disable read ahead */
1952 
1953 	ata_msense_push(ptr_io, last, page, sizeof(page));
1954 	return sizeof(page);
1955 }
1956 
1957 /**
1958  *	ata_msense_ctl_mode - Simulate MODE SENSE control mode page
1959  *	@dev: Device associated with this MODE SENSE command
1960  *	@ptr_io: (input/output) Location to store more output data
1961  *	@last: End of output data buffer
1962  *
1963  *	Generate a generic MODE SENSE control mode page.
1964  *
1965  *	LOCKING:
1966  *	None.
1967  */
1968 
1969 static unsigned int ata_msense_ctl_mode(u8 **ptr_io, const u8 *last)
1970 {
1971 	ata_msense_push(ptr_io, last, def_control_mpage,
1972 			sizeof(def_control_mpage));
1973 	return sizeof(def_control_mpage);
1974 }
1975 
1976 /**
1977  *	ata_msense_rw_recovery - Simulate MODE SENSE r/w error recovery page
1978  *	@dev: Device associated with this MODE SENSE command
1979  *	@ptr_io: (input/output) Location to store more output data
1980  *	@last: End of output data buffer
1981  *
1982  *	Generate a generic MODE SENSE r/w error recovery page.
1983  *
1984  *	LOCKING:
1985  *	None.
1986  */
1987 
1988 static unsigned int ata_msense_rw_recovery(u8 **ptr_io, const u8 *last)
1989 {
1990 
1991 	ata_msense_push(ptr_io, last, def_rw_recovery_mpage,
1992 			sizeof(def_rw_recovery_mpage));
1993 	return sizeof(def_rw_recovery_mpage);
1994 }
1995 
1996 /*
1997  * We can turn this into a real blacklist if it's needed, for now just
1998  * blacklist any Maxtor BANC1G10 revision firmware
1999  */
2000 static int ata_dev_supports_fua(u16 *id)
2001 {
2002 	unsigned char model[ATA_ID_PROD_LEN + 1], fw[ATA_ID_FW_REV_LEN + 1];
2003 
2004 	if (!libata_fua)
2005 		return 0;
2006 	if (!ata_id_has_fua(id))
2007 		return 0;
2008 
2009 	ata_id_c_string(id, model, ATA_ID_PROD, sizeof(model));
2010 	ata_id_c_string(id, fw, ATA_ID_FW_REV, sizeof(fw));
2011 
2012 	if (strcmp(model, "Maxtor"))
2013 		return 1;
2014 	if (strcmp(fw, "BANC1G10"))
2015 		return 1;
2016 
2017 	return 0; /* blacklisted */
2018 }
2019 
2020 /**
2021  *	ata_scsiop_mode_sense - Simulate MODE SENSE 6, 10 commands
2022  *	@args: device IDENTIFY data / SCSI command of interest.
2023  *	@rbuf: Response buffer, to which simulated SCSI cmd output is sent.
2024  *	@buflen: Response buffer length.
2025  *
2026  *	Simulate MODE SENSE commands. Assume this is invoked for direct
2027  *	access devices (e.g. disks) only. There should be no block
2028  *	descriptor for other device types.
2029  *
2030  *	LOCKING:
2031  *	spin_lock_irqsave(host lock)
2032  */
2033 
2034 unsigned int ata_scsiop_mode_sense(struct ata_scsi_args *args, u8 *rbuf,
2035 				  unsigned int buflen)
2036 {
2037 	struct ata_device *dev = args->dev;
2038 	u8 *scsicmd = args->cmd->cmnd, *p, *last;
2039 	const u8 sat_blk_desc[] = {
2040 		0, 0, 0, 0,	/* number of blocks: sat unspecified */
2041 		0,
2042 		0, 0x2, 0x0	/* block length: 512 bytes */
2043 	};
2044 	u8 pg, spg;
2045 	unsigned int ebd, page_control, six_byte, output_len, alloc_len, minlen;
2046 	u8 dpofua;
2047 
2048 	VPRINTK("ENTER\n");
2049 
2050 	six_byte = (scsicmd[0] == MODE_SENSE);
2051 	ebd = !(scsicmd[1] & 0x8);      /* dbd bit inverted == edb */
2052 	/*
2053 	 * LLBA bit in msense(10) ignored (compliant)
2054 	 */
2055 
2056 	page_control = scsicmd[2] >> 6;
2057 	switch (page_control) {
2058 	case 0: /* current */
2059 		break;  /* supported */
2060 	case 3: /* saved */
2061 		goto saving_not_supp;
2062 	case 1: /* changeable */
2063 	case 2: /* defaults */
2064 	default:
2065 		goto invalid_fld;
2066 	}
2067 
2068 	if (six_byte) {
2069 		output_len = 4 + (ebd ? 8 : 0);
2070 		alloc_len = scsicmd[4];
2071 	} else {
2072 		output_len = 8 + (ebd ? 8 : 0);
2073 		alloc_len = (scsicmd[7] << 8) + scsicmd[8];
2074 	}
2075 	minlen = (alloc_len < buflen) ? alloc_len : buflen;
2076 
2077 	p = rbuf + output_len;
2078 	last = rbuf + minlen - 1;
2079 
2080 	pg = scsicmd[2] & 0x3f;
2081 	spg = scsicmd[3];
2082 	/*
2083 	 * No mode subpages supported (yet) but asking for _all_
2084 	 * subpages may be valid
2085 	 */
2086 	if (spg && (spg != ALL_SUB_MPAGES))
2087 		goto invalid_fld;
2088 
2089 	switch(pg) {
2090 	case RW_RECOVERY_MPAGE:
2091 		output_len += ata_msense_rw_recovery(&p, last);
2092 		break;
2093 
2094 	case CACHE_MPAGE:
2095 		output_len += ata_msense_caching(args->id, &p, last);
2096 		break;
2097 
2098 	case CONTROL_MPAGE: {
2099 		output_len += ata_msense_ctl_mode(&p, last);
2100 		break;
2101 		}
2102 
2103 	case ALL_MPAGES:
2104 		output_len += ata_msense_rw_recovery(&p, last);
2105 		output_len += ata_msense_caching(args->id, &p, last);
2106 		output_len += ata_msense_ctl_mode(&p, last);
2107 		break;
2108 
2109 	default:		/* invalid page code */
2110 		goto invalid_fld;
2111 	}
2112 
2113 	if (minlen < 1)
2114 		return 0;
2115 
2116 	dpofua = 0;
2117 	if (ata_dev_supports_fua(args->id) && (dev->flags & ATA_DFLAG_LBA48) &&
2118 	    (!(dev->flags & ATA_DFLAG_PIO) || dev->multi_count))
2119 		dpofua = 1 << 4;
2120 
2121 	if (six_byte) {
2122 		output_len--;
2123 		rbuf[0] = output_len;
2124 		if (minlen > 2)
2125 			rbuf[2] |= dpofua;
2126 		if (ebd) {
2127 			if (minlen > 3)
2128 				rbuf[3] = sizeof(sat_blk_desc);
2129 			if (minlen > 11)
2130 				memcpy(rbuf + 4, sat_blk_desc,
2131 				       sizeof(sat_blk_desc));
2132 		}
2133 	} else {
2134 		output_len -= 2;
2135 		rbuf[0] = output_len >> 8;
2136 		if (minlen > 1)
2137 			rbuf[1] = output_len;
2138 		if (minlen > 3)
2139 			rbuf[3] |= dpofua;
2140 		if (ebd) {
2141 			if (minlen > 7)
2142 				rbuf[7] = sizeof(sat_blk_desc);
2143 			if (minlen > 15)
2144 				memcpy(rbuf + 8, sat_blk_desc,
2145 				       sizeof(sat_blk_desc));
2146 		}
2147 	}
2148 	return 0;
2149 
2150 invalid_fld:
2151 	ata_scsi_set_sense(args->cmd, ILLEGAL_REQUEST, 0x24, 0x0);
2152 	/* "Invalid field in cbd" */
2153 	return 1;
2154 
2155 saving_not_supp:
2156 	ata_scsi_set_sense(args->cmd, ILLEGAL_REQUEST, 0x39, 0x0);
2157 	 /* "Saving parameters not supported" */
2158 	return 1;
2159 }
2160 
2161 /**
2162  *	ata_scsiop_read_cap - Simulate READ CAPACITY[ 16] commands
2163  *	@args: device IDENTIFY data / SCSI command of interest.
2164  *	@rbuf: Response buffer, to which simulated SCSI cmd output is sent.
2165  *	@buflen: Response buffer length.
2166  *
2167  *	Simulate READ CAPACITY commands.
2168  *
2169  *	LOCKING:
2170  *	None.
2171  */
2172 unsigned int ata_scsiop_read_cap(struct ata_scsi_args *args, u8 *rbuf,
2173 			        unsigned int buflen)
2174 {
2175 	u64 last_lba = args->dev->n_sectors - 1; /* LBA of the last block */
2176 
2177 	VPRINTK("ENTER\n");
2178 
2179 	if (args->cmd->cmnd[0] == READ_CAPACITY) {
2180 		if (last_lba >= 0xffffffffULL)
2181 			last_lba = 0xffffffff;
2182 
2183 		/* sector count, 32-bit */
2184 		ATA_SCSI_RBUF_SET(0, last_lba >> (8 * 3));
2185 		ATA_SCSI_RBUF_SET(1, last_lba >> (8 * 2));
2186 		ATA_SCSI_RBUF_SET(2, last_lba >> (8 * 1));
2187 		ATA_SCSI_RBUF_SET(3, last_lba);
2188 
2189 		/* sector size */
2190 		ATA_SCSI_RBUF_SET(6, ATA_SECT_SIZE >> 8);
2191 		ATA_SCSI_RBUF_SET(7, ATA_SECT_SIZE);
2192 	} else {
2193 		/* sector count, 64-bit */
2194 		ATA_SCSI_RBUF_SET(0, last_lba >> (8 * 7));
2195 		ATA_SCSI_RBUF_SET(1, last_lba >> (8 * 6));
2196 		ATA_SCSI_RBUF_SET(2, last_lba >> (8 * 5));
2197 		ATA_SCSI_RBUF_SET(3, last_lba >> (8 * 4));
2198 		ATA_SCSI_RBUF_SET(4, last_lba >> (8 * 3));
2199 		ATA_SCSI_RBUF_SET(5, last_lba >> (8 * 2));
2200 		ATA_SCSI_RBUF_SET(6, last_lba >> (8 * 1));
2201 		ATA_SCSI_RBUF_SET(7, last_lba);
2202 
2203 		/* sector size */
2204 		ATA_SCSI_RBUF_SET(10, ATA_SECT_SIZE >> 8);
2205 		ATA_SCSI_RBUF_SET(11, ATA_SECT_SIZE);
2206 	}
2207 
2208 	return 0;
2209 }
2210 
2211 /**
2212  *	ata_scsiop_report_luns - Simulate REPORT LUNS command
2213  *	@args: device IDENTIFY data / SCSI command of interest.
2214  *	@rbuf: Response buffer, to which simulated SCSI cmd output is sent.
2215  *	@buflen: Response buffer length.
2216  *
2217  *	Simulate REPORT LUNS command.
2218  *
2219  *	LOCKING:
2220  *	spin_lock_irqsave(host lock)
2221  */
2222 
2223 unsigned int ata_scsiop_report_luns(struct ata_scsi_args *args, u8 *rbuf,
2224 				   unsigned int buflen)
2225 {
2226 	VPRINTK("ENTER\n");
2227 	rbuf[3] = 8;	/* just one lun, LUN 0, size 8 bytes */
2228 
2229 	return 0;
2230 }
2231 
2232 /**
2233  *	ata_scsi_set_sense - Set SCSI sense data and status
2234  *	@cmd: SCSI request to be handled
2235  *	@sk: SCSI-defined sense key
2236  *	@asc: SCSI-defined additional sense code
2237  *	@ascq: SCSI-defined additional sense code qualifier
2238  *
2239  *	Helper function that builds a valid fixed format, current
2240  *	response code and the given sense key (sk), additional sense
2241  *	code (asc) and additional sense code qualifier (ascq) with
2242  *	a SCSI command status of %SAM_STAT_CHECK_CONDITION and
2243  *	DRIVER_SENSE set in the upper bits of scsi_cmnd::result .
2244  *
2245  *	LOCKING:
2246  *	Not required
2247  */
2248 
2249 void ata_scsi_set_sense(struct scsi_cmnd *cmd, u8 sk, u8 asc, u8 ascq)
2250 {
2251 	cmd->result = (DRIVER_SENSE << 24) | SAM_STAT_CHECK_CONDITION;
2252 
2253 	cmd->sense_buffer[0] = 0x70;	/* fixed format, current */
2254 	cmd->sense_buffer[2] = sk;
2255 	cmd->sense_buffer[7] = 18 - 8;	/* additional sense length */
2256 	cmd->sense_buffer[12] = asc;
2257 	cmd->sense_buffer[13] = ascq;
2258 }
2259 
2260 /**
2261  *	ata_scsi_badcmd - End a SCSI request with an error
2262  *	@cmd: SCSI request to be handled
2263  *	@done: SCSI command completion function
2264  *	@asc: SCSI-defined additional sense code
2265  *	@ascq: SCSI-defined additional sense code qualifier
2266  *
2267  *	Helper function that completes a SCSI command with
2268  *	%SAM_STAT_CHECK_CONDITION, with a sense key %ILLEGAL_REQUEST
2269  *	and the specified additional sense codes.
2270  *
2271  *	LOCKING:
2272  *	spin_lock_irqsave(host lock)
2273  */
2274 
2275 void ata_scsi_badcmd(struct scsi_cmnd *cmd, void (*done)(struct scsi_cmnd *), u8 asc, u8 ascq)
2276 {
2277 	DPRINTK("ENTER\n");
2278 	ata_scsi_set_sense(cmd, ILLEGAL_REQUEST, asc, ascq);
2279 
2280 	done(cmd);
2281 }
2282 
2283 static void atapi_sense_complete(struct ata_queued_cmd *qc)
2284 {
2285 	if (qc->err_mask && ((qc->err_mask & AC_ERR_DEV) == 0)) {
2286 		/* FIXME: not quite right; we don't want the
2287 		 * translation of taskfile registers into
2288 		 * a sense descriptors, since that's only
2289 		 * correct for ATA, not ATAPI
2290 		 */
2291 		ata_gen_passthru_sense(qc);
2292 	}
2293 
2294 	qc->scsidone(qc->scsicmd);
2295 	ata_qc_free(qc);
2296 }
2297 
2298 /* is it pointless to prefer PIO for "safety reasons"? */
2299 static inline int ata_pio_use_silly(struct ata_port *ap)
2300 {
2301 	return (ap->flags & ATA_FLAG_PIO_DMA);
2302 }
2303 
2304 static void atapi_request_sense(struct ata_queued_cmd *qc)
2305 {
2306 	struct ata_port *ap = qc->ap;
2307 	struct scsi_cmnd *cmd = qc->scsicmd;
2308 
2309 	DPRINTK("ATAPI request sense\n");
2310 
2311 	/* FIXME: is this needed? */
2312 	memset(cmd->sense_buffer, 0, sizeof(cmd->sense_buffer));
2313 
2314 	ap->ops->tf_read(ap, &qc->tf);
2315 
2316 	/* fill these in, for the case where they are -not- overwritten */
2317 	cmd->sense_buffer[0] = 0x70;
2318 	cmd->sense_buffer[2] = qc->tf.feature >> 4;
2319 
2320 	ata_qc_reinit(qc);
2321 
2322 	ata_sg_init_one(qc, cmd->sense_buffer, sizeof(cmd->sense_buffer));
2323 	qc->dma_dir = DMA_FROM_DEVICE;
2324 
2325 	memset(&qc->cdb, 0, qc->dev->cdb_len);
2326 	qc->cdb[0] = REQUEST_SENSE;
2327 	qc->cdb[4] = SCSI_SENSE_BUFFERSIZE;
2328 
2329 	qc->tf.flags |= ATA_TFLAG_ISADDR | ATA_TFLAG_DEVICE;
2330 	qc->tf.command = ATA_CMD_PACKET;
2331 
2332 	if (ata_pio_use_silly(ap)) {
2333 		qc->tf.protocol = ATA_PROT_ATAPI_DMA;
2334 		qc->tf.feature |= ATAPI_PKT_DMA;
2335 	} else {
2336 		qc->tf.protocol = ATA_PROT_ATAPI;
2337 		qc->tf.lbam = (8 * 1024) & 0xff;
2338 		qc->tf.lbah = (8 * 1024) >> 8;
2339 	}
2340 	qc->nbytes = SCSI_SENSE_BUFFERSIZE;
2341 
2342 	qc->complete_fn = atapi_sense_complete;
2343 
2344 	ata_qc_issue(qc);
2345 
2346 	DPRINTK("EXIT\n");
2347 }
2348 
2349 static void atapi_qc_complete(struct ata_queued_cmd *qc)
2350 {
2351 	struct scsi_cmnd *cmd = qc->scsicmd;
2352 	unsigned int err_mask = qc->err_mask;
2353 
2354 	VPRINTK("ENTER, err_mask 0x%X\n", err_mask);
2355 
2356 	/* handle completion from new EH */
2357 	if (unlikely(qc->ap->ops->error_handler &&
2358 		     (err_mask || qc->flags & ATA_QCFLAG_SENSE_VALID))) {
2359 
2360 		if (!(qc->flags & ATA_QCFLAG_SENSE_VALID)) {
2361 			/* FIXME: not quite right; we don't want the
2362 			 * translation of taskfile registers into a
2363 			 * sense descriptors, since that's only
2364 			 * correct for ATA, not ATAPI
2365 			 */
2366 			ata_gen_passthru_sense(qc);
2367 		}
2368 
2369 		/* SCSI EH automatically locks door if sdev->locked is
2370 		 * set.  Sometimes door lock request continues to
2371 		 * fail, for example, when no media is present.  This
2372 		 * creates a loop - SCSI EH issues door lock which
2373 		 * fails and gets invoked again to acquire sense data
2374 		 * for the failed command.
2375 		 *
2376 		 * If door lock fails, always clear sdev->locked to
2377 		 * avoid this infinite loop.
2378 		 */
2379 		if (qc->cdb[0] == ALLOW_MEDIUM_REMOVAL)
2380 			qc->dev->sdev->locked = 0;
2381 
2382 		qc->scsicmd->result = SAM_STAT_CHECK_CONDITION;
2383 		qc->scsidone(cmd);
2384 		ata_qc_free(qc);
2385 		return;
2386 	}
2387 
2388 	/* successful completion or old EH failure path */
2389 	if (unlikely(err_mask & AC_ERR_DEV)) {
2390 		cmd->result = SAM_STAT_CHECK_CONDITION;
2391 		atapi_request_sense(qc);
2392 		return;
2393 	} else if (unlikely(err_mask)) {
2394 		/* FIXME: not quite right; we don't want the
2395 		 * translation of taskfile registers into
2396 		 * a sense descriptors, since that's only
2397 		 * correct for ATA, not ATAPI
2398 		 */
2399 		ata_gen_passthru_sense(qc);
2400 	} else {
2401 		u8 *scsicmd = cmd->cmnd;
2402 
2403 		if ((scsicmd[0] == INQUIRY) && ((scsicmd[1] & 0x03) == 0)) {
2404 			u8 *buf = NULL;
2405 			unsigned int buflen;
2406 
2407 			buflen = ata_scsi_rbuf_get(cmd, &buf);
2408 
2409 	/* ATAPI devices typically report zero for their SCSI version,
2410 	 * and sometimes deviate from the spec WRT response data
2411 	 * format.  If SCSI version is reported as zero like normal,
2412 	 * then we make the following fixups:  1) Fake MMC-5 version,
2413 	 * to indicate to the Linux scsi midlayer this is a modern
2414 	 * device.  2) Ensure response data format / ATAPI information
2415 	 * are always correct.
2416 	 */
2417 			if (buf[2] == 0) {
2418 				buf[2] = 0x5;
2419 				buf[3] = 0x32;
2420 			}
2421 
2422 			ata_scsi_rbuf_put(cmd, buf);
2423 		}
2424 
2425 		cmd->result = SAM_STAT_GOOD;
2426 	}
2427 
2428 	qc->scsidone(cmd);
2429 	ata_qc_free(qc);
2430 }
2431 /**
2432  *	atapi_xlat - Initialize PACKET taskfile
2433  *	@qc: command structure to be initialized
2434  *
2435  *	LOCKING:
2436  *	spin_lock_irqsave(host lock)
2437  *
2438  *	RETURNS:
2439  *	Zero on success, non-zero on failure.
2440  */
2441 static unsigned int atapi_xlat(struct ata_queued_cmd *qc)
2442 {
2443 	struct scsi_cmnd *scmd = qc->scsicmd;
2444 	struct ata_device *dev = qc->dev;
2445 	int using_pio = (dev->flags & ATA_DFLAG_PIO);
2446 	int nodata = (scmd->sc_data_direction == DMA_NONE);
2447 
2448 	if (!using_pio)
2449 		/* Check whether ATAPI DMA is safe */
2450 		if (ata_check_atapi_dma(qc))
2451 			using_pio = 1;
2452 
2453 	memset(qc->cdb, 0, dev->cdb_len);
2454 	memcpy(qc->cdb, scmd->cmnd, scmd->cmd_len);
2455 
2456 	qc->complete_fn = atapi_qc_complete;
2457 
2458 	qc->tf.flags |= ATA_TFLAG_ISADDR | ATA_TFLAG_DEVICE;
2459 	if (scmd->sc_data_direction == DMA_TO_DEVICE) {
2460 		qc->tf.flags |= ATA_TFLAG_WRITE;
2461 		DPRINTK("direction: write\n");
2462 	}
2463 
2464 	qc->tf.command = ATA_CMD_PACKET;
2465 
2466 	/* no data, or PIO data xfer */
2467 	if (using_pio || nodata) {
2468 		if (nodata)
2469 			qc->tf.protocol = ATA_PROT_ATAPI_NODATA;
2470 		else
2471 			qc->tf.protocol = ATA_PROT_ATAPI;
2472 		qc->tf.lbam = (8 * 1024) & 0xff;
2473 		qc->tf.lbah = (8 * 1024) >> 8;
2474 	}
2475 
2476 	/* DMA data xfer */
2477 	else {
2478 		qc->tf.protocol = ATA_PROT_ATAPI_DMA;
2479 		qc->tf.feature |= ATAPI_PKT_DMA;
2480 
2481 		if (atapi_dmadir && (scmd->sc_data_direction != DMA_TO_DEVICE))
2482 			/* some SATA bridges need us to indicate data xfer direction */
2483 			qc->tf.feature |= ATAPI_DMADIR;
2484 	}
2485 
2486 	qc->nbytes = scmd->request_bufflen;
2487 
2488 	return 0;
2489 }
2490 
2491 static struct ata_device * ata_find_dev(struct ata_port *ap, int id)
2492 {
2493 	if (likely(id < ATA_MAX_DEVICES))
2494 		return &ap->device[id];
2495 	return NULL;
2496 }
2497 
2498 static struct ata_device * __ata_scsi_find_dev(struct ata_port *ap,
2499 					const struct scsi_device *scsidev)
2500 {
2501 	/* skip commands not addressed to targets we simulate */
2502 	if (unlikely(scsidev->channel || scsidev->lun))
2503 		return NULL;
2504 
2505 	return ata_find_dev(ap, scsidev->id);
2506 }
2507 
2508 /**
2509  *	ata_scsi_dev_enabled - determine if device is enabled
2510  *	@dev: ATA device
2511  *
2512  *	Determine if commands should be sent to the specified device.
2513  *
2514  *	LOCKING:
2515  *	spin_lock_irqsave(host lock)
2516  *
2517  *	RETURNS:
2518  *	0 if commands are not allowed / 1 if commands are allowed
2519  */
2520 
2521 static int ata_scsi_dev_enabled(struct ata_device *dev)
2522 {
2523 	if (unlikely(!ata_dev_enabled(dev)))
2524 		return 0;
2525 
2526 	if (!atapi_enabled || (dev->ap->flags & ATA_FLAG_NO_ATAPI)) {
2527 		if (unlikely(dev->class == ATA_DEV_ATAPI)) {
2528 			ata_dev_printk(dev, KERN_WARNING,
2529 				       "WARNING: ATAPI is %s, device ignored.\n",
2530 				       atapi_enabled ? "not supported with this driver" : "disabled");
2531 			return 0;
2532 		}
2533 	}
2534 
2535 	return 1;
2536 }
2537 
2538 /**
2539  *	ata_scsi_find_dev - lookup ata_device from scsi_cmnd
2540  *	@ap: ATA port to which the device is attached
2541  *	@scsidev: SCSI device from which we derive the ATA device
2542  *
2543  *	Given various information provided in struct scsi_cmnd,
2544  *	map that onto an ATA bus, and using that mapping
2545  *	determine which ata_device is associated with the
2546  *	SCSI command to be sent.
2547  *
2548  *	LOCKING:
2549  *	spin_lock_irqsave(host lock)
2550  *
2551  *	RETURNS:
2552  *	Associated ATA device, or %NULL if not found.
2553  */
2554 static struct ata_device *
2555 ata_scsi_find_dev(struct ata_port *ap, const struct scsi_device *scsidev)
2556 {
2557 	struct ata_device *dev = __ata_scsi_find_dev(ap, scsidev);
2558 
2559 	if (unlikely(!dev || !ata_scsi_dev_enabled(dev)))
2560 		return NULL;
2561 
2562 	return dev;
2563 }
2564 
2565 /*
2566  *	ata_scsi_map_proto - Map pass-thru protocol value to taskfile value.
2567  *	@byte1: Byte 1 from pass-thru CDB.
2568  *
2569  *	RETURNS:
2570  *	ATA_PROT_UNKNOWN if mapping failed/unimplemented, protocol otherwise.
2571  */
2572 static u8
2573 ata_scsi_map_proto(u8 byte1)
2574 {
2575 	switch((byte1 & 0x1e) >> 1) {
2576 		case 3:		/* Non-data */
2577 			return ATA_PROT_NODATA;
2578 
2579 		case 6:		/* DMA */
2580 			return ATA_PROT_DMA;
2581 
2582 		case 4:		/* PIO Data-in */
2583 		case 5:		/* PIO Data-out */
2584 			return ATA_PROT_PIO;
2585 
2586 		case 10:	/* Device Reset */
2587 		case 0:		/* Hard Reset */
2588 		case 1:		/* SRST */
2589 		case 2:		/* Bus Idle */
2590 		case 7:		/* Packet */
2591 		case 8:		/* DMA Queued */
2592 		case 9:		/* Device Diagnostic */
2593 		case 11:	/* UDMA Data-in */
2594 		case 12:	/* UDMA Data-Out */
2595 		case 13:	/* FPDMA */
2596 		default:	/* Reserved */
2597 			break;
2598 	}
2599 
2600 	return ATA_PROT_UNKNOWN;
2601 }
2602 
2603 /**
2604  *	ata_scsi_pass_thru - convert ATA pass-thru CDB to taskfile
2605  *	@qc: command structure to be initialized
2606  *
2607  *	Handles either 12 or 16-byte versions of the CDB.
2608  *
2609  *	RETURNS:
2610  *	Zero on success, non-zero on failure.
2611  */
2612 static unsigned int ata_scsi_pass_thru(struct ata_queued_cmd *qc)
2613 {
2614 	struct ata_taskfile *tf = &(qc->tf);
2615 	struct scsi_cmnd *scmd = qc->scsicmd;
2616 	struct ata_device *dev = qc->dev;
2617 	const u8 *cdb = scmd->cmnd;
2618 
2619 	if ((tf->protocol = ata_scsi_map_proto(cdb[1])) == ATA_PROT_UNKNOWN)
2620 		goto invalid_fld;
2621 
2622 	/* We may not issue DMA commands if no DMA mode is set */
2623 	if (tf->protocol == ATA_PROT_DMA && dev->dma_mode == 0)
2624 		goto invalid_fld;
2625 
2626 	if (cdb[1] & 0xe0)
2627 		/* PIO multi not supported yet */
2628 		goto invalid_fld;
2629 
2630 	/*
2631 	 * 12 and 16 byte CDBs use different offsets to
2632 	 * provide the various register values.
2633 	 */
2634 	if (cdb[0] == ATA_16) {
2635 		/*
2636 		 * 16-byte CDB - may contain extended commands.
2637 		 *
2638 		 * If that is the case, copy the upper byte register values.
2639 		 */
2640 		if (cdb[1] & 0x01) {
2641 			tf->hob_feature = cdb[3];
2642 			tf->hob_nsect = cdb[5];
2643 			tf->hob_lbal = cdb[7];
2644 			tf->hob_lbam = cdb[9];
2645 			tf->hob_lbah = cdb[11];
2646 			tf->flags |= ATA_TFLAG_LBA48;
2647 		} else
2648 			tf->flags &= ~ATA_TFLAG_LBA48;
2649 
2650 		/*
2651 		 * Always copy low byte, device and command registers.
2652 		 */
2653 		tf->feature = cdb[4];
2654 		tf->nsect = cdb[6];
2655 		tf->lbal = cdb[8];
2656 		tf->lbam = cdb[10];
2657 		tf->lbah = cdb[12];
2658 		tf->device = cdb[13];
2659 		tf->command = cdb[14];
2660 	} else {
2661 		/*
2662 		 * 12-byte CDB - incapable of extended commands.
2663 		 */
2664 		tf->flags &= ~ATA_TFLAG_LBA48;
2665 
2666 		tf->feature = cdb[3];
2667 		tf->nsect = cdb[4];
2668 		tf->lbal = cdb[5];
2669 		tf->lbam = cdb[6];
2670 		tf->lbah = cdb[7];
2671 		tf->device = cdb[8];
2672 		tf->command = cdb[9];
2673 	}
2674 	/*
2675 	 * If slave is possible, enforce correct master/slave bit
2676 	*/
2677 	if (qc->ap->flags & ATA_FLAG_SLAVE_POSS)
2678 		tf->device = qc->dev->devno ?
2679 			tf->device | ATA_DEV1 : tf->device & ~ATA_DEV1;
2680 
2681 	/*
2682 	 * Filter SET_FEATURES - XFER MODE command -- otherwise,
2683 	 * SET_FEATURES - XFER MODE must be preceded/succeeded
2684 	 * by an update to hardware-specific registers for each
2685 	 * controller (i.e. the reason for ->set_piomode(),
2686 	 * ->set_dmamode(), and ->post_set_mode() hooks).
2687 	 */
2688 	if ((tf->command == ATA_CMD_SET_FEATURES)
2689 	 && (tf->feature == SETFEATURES_XFER))
2690 		goto invalid_fld;
2691 
2692 	/*
2693 	 * Set flags so that all registers will be written,
2694 	 * and pass on write indication (used for PIO/DMA
2695 	 * setup.)
2696 	 */
2697 	tf->flags |= (ATA_TFLAG_ISADDR | ATA_TFLAG_DEVICE);
2698 
2699 	if (scmd->sc_data_direction == DMA_TO_DEVICE)
2700 		tf->flags |= ATA_TFLAG_WRITE;
2701 
2702 	/*
2703 	 * Set transfer length.
2704 	 *
2705 	 * TODO: find out if we need to do more here to
2706 	 *       cover scatter/gather case.
2707 	 */
2708 	qc->nbytes = scmd->request_bufflen;
2709 
2710 	/* request result TF */
2711 	qc->flags |= ATA_QCFLAG_RESULT_TF;
2712 
2713 	return 0;
2714 
2715  invalid_fld:
2716 	ata_scsi_set_sense(scmd, ILLEGAL_REQUEST, 0x24, 0x00);
2717 	/* "Invalid field in cdb" */
2718 	return 1;
2719 }
2720 
2721 /**
2722  *	ata_get_xlat_func - check if SCSI to ATA translation is possible
2723  *	@dev: ATA device
2724  *	@cmd: SCSI command opcode to consider
2725  *
2726  *	Look up the SCSI command given, and determine whether the
2727  *	SCSI command is to be translated or simulated.
2728  *
2729  *	RETURNS:
2730  *	Pointer to translation function if possible, %NULL if not.
2731  */
2732 
2733 static inline ata_xlat_func_t ata_get_xlat_func(struct ata_device *dev, u8 cmd)
2734 {
2735 	switch (cmd) {
2736 	case READ_6:
2737 	case READ_10:
2738 	case READ_16:
2739 
2740 	case WRITE_6:
2741 	case WRITE_10:
2742 	case WRITE_16:
2743 		return ata_scsi_rw_xlat;
2744 
2745 	case SYNCHRONIZE_CACHE:
2746 		if (ata_try_flush_cache(dev))
2747 			return ata_scsi_flush_xlat;
2748 		break;
2749 
2750 	case VERIFY:
2751 	case VERIFY_16:
2752 		return ata_scsi_verify_xlat;
2753 
2754 	case ATA_12:
2755 	case ATA_16:
2756 		return ata_scsi_pass_thru;
2757 
2758 	case START_STOP:
2759 		return ata_scsi_start_stop_xlat;
2760 	}
2761 
2762 	return NULL;
2763 }
2764 
2765 /**
2766  *	ata_scsi_dump_cdb - dump SCSI command contents to dmesg
2767  *	@ap: ATA port to which the command was being sent
2768  *	@cmd: SCSI command to dump
2769  *
2770  *	Prints the contents of a SCSI command via printk().
2771  */
2772 
2773 static inline void ata_scsi_dump_cdb(struct ata_port *ap,
2774 				     struct scsi_cmnd *cmd)
2775 {
2776 #ifdef ATA_DEBUG
2777 	struct scsi_device *scsidev = cmd->device;
2778 	u8 *scsicmd = cmd->cmnd;
2779 
2780 	DPRINTK("CDB (%u:%d,%d,%d) %02x %02x %02x %02x %02x %02x %02x %02x %02x\n",
2781 		ap->print_id,
2782 		scsidev->channel, scsidev->id, scsidev->lun,
2783 		scsicmd[0], scsicmd[1], scsicmd[2], scsicmd[3],
2784 		scsicmd[4], scsicmd[5], scsicmd[6], scsicmd[7],
2785 		scsicmd[8]);
2786 #endif
2787 }
2788 
2789 static inline int __ata_scsi_queuecmd(struct scsi_cmnd *scmd,
2790 				      void (*done)(struct scsi_cmnd *),
2791 				      struct ata_device *dev)
2792 {
2793 	int rc = 0;
2794 
2795 	if (unlikely(!scmd->cmd_len)) {
2796 		ata_dev_printk(dev, KERN_WARNING, "WARNING: zero len CDB\n");
2797 		scmd->result = DID_ERROR << 16;
2798 		done(scmd);
2799 		return 0;
2800 	}
2801 
2802 	if (dev->class == ATA_DEV_ATA) {
2803 		ata_xlat_func_t xlat_func = ata_get_xlat_func(dev,
2804 							      scmd->cmnd[0]);
2805 
2806 		if (xlat_func)
2807 			rc = ata_scsi_translate(dev, scmd, done, xlat_func);
2808 		else
2809 			ata_scsi_simulate(dev, scmd, done);
2810 	} else
2811 		rc = ata_scsi_translate(dev, scmd, done, atapi_xlat);
2812 
2813 	return rc;
2814 }
2815 
2816 /**
2817  *	ata_scsi_queuecmd - Issue SCSI cdb to libata-managed device
2818  *	@cmd: SCSI command to be sent
2819  *	@done: Completion function, called when command is complete
2820  *
2821  *	In some cases, this function translates SCSI commands into
2822  *	ATA taskfiles, and queues the taskfiles to be sent to
2823  *	hardware.  In other cases, this function simulates a
2824  *	SCSI device by evaluating and responding to certain
2825  *	SCSI commands.  This creates the overall effect of
2826  *	ATA and ATAPI devices appearing as SCSI devices.
2827  *
2828  *	LOCKING:
2829  *	Releases scsi-layer-held lock, and obtains host lock.
2830  *
2831  *	RETURNS:
2832  *	Return value from __ata_scsi_queuecmd() if @cmd can be queued,
2833  *	0 otherwise.
2834  */
2835 int ata_scsi_queuecmd(struct scsi_cmnd *cmd, void (*done)(struct scsi_cmnd *))
2836 {
2837 	struct ata_port *ap;
2838 	struct ata_device *dev;
2839 	struct scsi_device *scsidev = cmd->device;
2840 	struct Scsi_Host *shost = scsidev->host;
2841 	int rc = 0;
2842 
2843 	ap = ata_shost_to_port(shost);
2844 
2845 	spin_unlock(shost->host_lock);
2846 	spin_lock(ap->lock);
2847 
2848 	ata_scsi_dump_cdb(ap, cmd);
2849 
2850 	dev = ata_scsi_find_dev(ap, scsidev);
2851 	if (likely(dev))
2852 		rc = __ata_scsi_queuecmd(cmd, done, dev);
2853 	else {
2854 		cmd->result = (DID_BAD_TARGET << 16);
2855 		done(cmd);
2856 	}
2857 
2858 	spin_unlock(ap->lock);
2859 	spin_lock(shost->host_lock);
2860 	return rc;
2861 }
2862 
2863 /**
2864  *	ata_scsi_simulate - simulate SCSI command on ATA device
2865  *	@dev: the target device
2866  *	@cmd: SCSI command being sent to device.
2867  *	@done: SCSI command completion function.
2868  *
2869  *	Interprets and directly executes a select list of SCSI commands
2870  *	that can be handled internally.
2871  *
2872  *	LOCKING:
2873  *	spin_lock_irqsave(host lock)
2874  */
2875 
2876 void ata_scsi_simulate(struct ata_device *dev, struct scsi_cmnd *cmd,
2877 		      void (*done)(struct scsi_cmnd *))
2878 {
2879 	struct ata_scsi_args args;
2880 	const u8 *scsicmd = cmd->cmnd;
2881 
2882 	args.dev = dev;
2883 	args.id = dev->id;
2884 	args.cmd = cmd;
2885 	args.done = done;
2886 
2887 	switch(scsicmd[0]) {
2888 		/* no-op's, complete with success */
2889 		case SYNCHRONIZE_CACHE:
2890 		case REZERO_UNIT:
2891 		case SEEK_6:
2892 		case SEEK_10:
2893 		case TEST_UNIT_READY:
2894 		case FORMAT_UNIT:		/* FIXME: correct? */
2895 		case SEND_DIAGNOSTIC:		/* FIXME: correct? */
2896 			ata_scsi_rbuf_fill(&args, ata_scsiop_noop);
2897 			break;
2898 
2899 		case INQUIRY:
2900 			if (scsicmd[1] & 2)	           /* is CmdDt set?  */
2901 				ata_scsi_invalid_field(cmd, done);
2902 			else if ((scsicmd[1] & 1) == 0)    /* is EVPD clear? */
2903 				ata_scsi_rbuf_fill(&args, ata_scsiop_inq_std);
2904 			else if (scsicmd[2] == 0x00)
2905 				ata_scsi_rbuf_fill(&args, ata_scsiop_inq_00);
2906 			else if (scsicmd[2] == 0x80)
2907 				ata_scsi_rbuf_fill(&args, ata_scsiop_inq_80);
2908 			else if (scsicmd[2] == 0x83)
2909 				ata_scsi_rbuf_fill(&args, ata_scsiop_inq_83);
2910 			else
2911 				ata_scsi_invalid_field(cmd, done);
2912 			break;
2913 
2914 		case MODE_SENSE:
2915 		case MODE_SENSE_10:
2916 			ata_scsi_rbuf_fill(&args, ata_scsiop_mode_sense);
2917 			break;
2918 
2919 		case MODE_SELECT:	/* unconditionally return */
2920 		case MODE_SELECT_10:	/* bad-field-in-cdb */
2921 			ata_scsi_invalid_field(cmd, done);
2922 			break;
2923 
2924 		case READ_CAPACITY:
2925 			ata_scsi_rbuf_fill(&args, ata_scsiop_read_cap);
2926 			break;
2927 
2928 		case SERVICE_ACTION_IN:
2929 			if ((scsicmd[1] & 0x1f) == SAI_READ_CAPACITY_16)
2930 				ata_scsi_rbuf_fill(&args, ata_scsiop_read_cap);
2931 			else
2932 				ata_scsi_invalid_field(cmd, done);
2933 			break;
2934 
2935 		case REPORT_LUNS:
2936 			ata_scsi_rbuf_fill(&args, ata_scsiop_report_luns);
2937 			break;
2938 
2939 		/* mandatory commands we haven't implemented yet */
2940 		case REQUEST_SENSE:
2941 
2942 		/* all other commands */
2943 		default:
2944 			ata_scsi_set_sense(cmd, ILLEGAL_REQUEST, 0x20, 0x0);
2945 			/* "Invalid command operation code" */
2946 			done(cmd);
2947 			break;
2948 	}
2949 }
2950 
2951 void ata_scsi_scan_host(struct ata_port *ap)
2952 {
2953 	unsigned int i;
2954 
2955 	if (ap->flags & ATA_FLAG_DISABLED)
2956 		return;
2957 
2958 	for (i = 0; i < ATA_MAX_DEVICES; i++) {
2959 		struct ata_device *dev = &ap->device[i];
2960 		struct scsi_device *sdev;
2961 
2962 		if (!ata_dev_enabled(dev) || dev->sdev)
2963 			continue;
2964 
2965 		sdev = __scsi_add_device(ap->scsi_host, 0, i, 0, NULL);
2966 		if (!IS_ERR(sdev)) {
2967 			dev->sdev = sdev;
2968 			scsi_device_put(sdev);
2969 		}
2970 	}
2971 }
2972 
2973 /**
2974  *	ata_scsi_offline_dev - offline attached SCSI device
2975  *	@dev: ATA device to offline attached SCSI device for
2976  *
2977  *	This function is called from ata_eh_hotplug() and responsible
2978  *	for taking the SCSI device attached to @dev offline.  This
2979  *	function is called with host lock which protects dev->sdev
2980  *	against clearing.
2981  *
2982  *	LOCKING:
2983  *	spin_lock_irqsave(host lock)
2984  *
2985  *	RETURNS:
2986  *	1 if attached SCSI device exists, 0 otherwise.
2987  */
2988 int ata_scsi_offline_dev(struct ata_device *dev)
2989 {
2990 	if (dev->sdev) {
2991 		scsi_device_set_state(dev->sdev, SDEV_OFFLINE);
2992 		return 1;
2993 	}
2994 	return 0;
2995 }
2996 
2997 /**
2998  *	ata_scsi_remove_dev - remove attached SCSI device
2999  *	@dev: ATA device to remove attached SCSI device for
3000  *
3001  *	This function is called from ata_eh_scsi_hotplug() and
3002  *	responsible for removing the SCSI device attached to @dev.
3003  *
3004  *	LOCKING:
3005  *	Kernel thread context (may sleep).
3006  */
3007 static void ata_scsi_remove_dev(struct ata_device *dev)
3008 {
3009 	struct ata_port *ap = dev->ap;
3010 	struct scsi_device *sdev;
3011 	unsigned long flags;
3012 
3013 	/* Alas, we need to grab scan_mutex to ensure SCSI device
3014 	 * state doesn't change underneath us and thus
3015 	 * scsi_device_get() always succeeds.  The mutex locking can
3016 	 * be removed if there is __scsi_device_get() interface which
3017 	 * increments reference counts regardless of device state.
3018 	 */
3019 	mutex_lock(&ap->scsi_host->scan_mutex);
3020 	spin_lock_irqsave(ap->lock, flags);
3021 
3022 	/* clearing dev->sdev is protected by host lock */
3023 	sdev = dev->sdev;
3024 	dev->sdev = NULL;
3025 
3026 	if (sdev) {
3027 		/* If user initiated unplug races with us, sdev can go
3028 		 * away underneath us after the host lock and
3029 		 * scan_mutex are released.  Hold onto it.
3030 		 */
3031 		if (scsi_device_get(sdev) == 0) {
3032 			/* The following ensures the attached sdev is
3033 			 * offline on return from ata_scsi_offline_dev()
3034 			 * regardless it wins or loses the race
3035 			 * against this function.
3036 			 */
3037 			scsi_device_set_state(sdev, SDEV_OFFLINE);
3038 		} else {
3039 			WARN_ON(1);
3040 			sdev = NULL;
3041 		}
3042 	}
3043 
3044 	spin_unlock_irqrestore(ap->lock, flags);
3045 	mutex_unlock(&ap->scsi_host->scan_mutex);
3046 
3047 	if (sdev) {
3048 		ata_dev_printk(dev, KERN_INFO, "detaching (SCSI %s)\n",
3049 			       sdev->sdev_gendev.bus_id);
3050 
3051 		scsi_remove_device(sdev);
3052 		scsi_device_put(sdev);
3053 	}
3054 }
3055 
3056 /**
3057  *	ata_scsi_hotplug - SCSI part of hotplug
3058  *	@work: Pointer to ATA port to perform SCSI hotplug on
3059  *
3060  *	Perform SCSI part of hotplug.  It's executed from a separate
3061  *	workqueue after EH completes.  This is necessary because SCSI
3062  *	hot plugging requires working EH and hot unplugging is
3063  *	synchronized with hot plugging with a mutex.
3064  *
3065  *	LOCKING:
3066  *	Kernel thread context (may sleep).
3067  */
3068 void ata_scsi_hotplug(struct work_struct *work)
3069 {
3070 	struct ata_port *ap =
3071 		container_of(work, struct ata_port, hotplug_task.work);
3072 	int i;
3073 
3074 	if (ap->pflags & ATA_PFLAG_UNLOADING) {
3075 		DPRINTK("ENTER/EXIT - unloading\n");
3076 		return;
3077 	}
3078 
3079 	DPRINTK("ENTER\n");
3080 
3081 	/* unplug detached devices */
3082 	for (i = 0; i < ATA_MAX_DEVICES; i++) {
3083 		struct ata_device *dev = &ap->device[i];
3084 		unsigned long flags;
3085 
3086 		if (!(dev->flags & ATA_DFLAG_DETACHED))
3087 			continue;
3088 
3089 		spin_lock_irqsave(ap->lock, flags);
3090 		dev->flags &= ~ATA_DFLAG_DETACHED;
3091 		spin_unlock_irqrestore(ap->lock, flags);
3092 
3093 		ata_scsi_remove_dev(dev);
3094 	}
3095 
3096 	/* scan for new ones */
3097 	ata_scsi_scan_host(ap);
3098 
3099 	/* If we scanned while EH was in progress, scan would have
3100 	 * failed silently.  Requeue if there are enabled but
3101 	 * unattached devices.
3102 	 */
3103 	for (i = 0; i < ATA_MAX_DEVICES; i++) {
3104 		struct ata_device *dev = &ap->device[i];
3105 		if (ata_dev_enabled(dev) && !dev->sdev) {
3106 			queue_delayed_work(ata_aux_wq, &ap->hotplug_task,
3107 				round_jiffies_relative(HZ));
3108 			break;
3109 		}
3110 	}
3111 
3112 	DPRINTK("EXIT\n");
3113 }
3114 
3115 /**
3116  *	ata_scsi_user_scan - indication for user-initiated bus scan
3117  *	@shost: SCSI host to scan
3118  *	@channel: Channel to scan
3119  *	@id: ID to scan
3120  *	@lun: LUN to scan
3121  *
3122  *	This function is called when user explicitly requests bus
3123  *	scan.  Set probe pending flag and invoke EH.
3124  *
3125  *	LOCKING:
3126  *	SCSI layer (we don't care)
3127  *
3128  *	RETURNS:
3129  *	Zero.
3130  */
3131 static int ata_scsi_user_scan(struct Scsi_Host *shost, unsigned int channel,
3132 			      unsigned int id, unsigned int lun)
3133 {
3134 	struct ata_port *ap = ata_shost_to_port(shost);
3135 	unsigned long flags;
3136 	int rc = 0;
3137 
3138 	if (!ap->ops->error_handler)
3139 		return -EOPNOTSUPP;
3140 
3141 	if ((channel != SCAN_WILD_CARD && channel != 0) ||
3142 	    (lun != SCAN_WILD_CARD && lun != 0))
3143 		return -EINVAL;
3144 
3145 	spin_lock_irqsave(ap->lock, flags);
3146 
3147 	if (id == SCAN_WILD_CARD) {
3148 		ap->eh_info.probe_mask |= (1 << ATA_MAX_DEVICES) - 1;
3149 		ap->eh_info.action |= ATA_EH_SOFTRESET;
3150 	} else {
3151 		struct ata_device *dev = ata_find_dev(ap, id);
3152 
3153 		if (dev) {
3154 			ap->eh_info.probe_mask |= 1 << dev->devno;
3155 			ap->eh_info.action |= ATA_EH_SOFTRESET;
3156 			ap->eh_info.flags |= ATA_EHI_RESUME_LINK;
3157 		} else
3158 			rc = -EINVAL;
3159 	}
3160 
3161 	if (rc == 0) {
3162 		ata_port_schedule_eh(ap);
3163 		spin_unlock_irqrestore(ap->lock, flags);
3164 		ata_port_wait_eh(ap);
3165 	} else
3166 		spin_unlock_irqrestore(ap->lock, flags);
3167 
3168 	return rc;
3169 }
3170 
3171 /**
3172  *	ata_scsi_dev_rescan - initiate scsi_rescan_device()
3173  *	@work: Pointer to ATA port to perform scsi_rescan_device()
3174  *
3175  *	After ATA pass thru (SAT) commands are executed successfully,
3176  *	libata need to propagate the changes to SCSI layer.  This
3177  *	function must be executed from ata_aux_wq such that sdev
3178  *	attach/detach don't race with rescan.
3179  *
3180  *	LOCKING:
3181  *	Kernel thread context (may sleep).
3182  */
3183 void ata_scsi_dev_rescan(struct work_struct *work)
3184 {
3185 	struct ata_port *ap =
3186 		container_of(work, struct ata_port, scsi_rescan_task);
3187 	unsigned long flags;
3188 	unsigned int i;
3189 
3190 	spin_lock_irqsave(ap->lock, flags);
3191 
3192 	for (i = 0; i < ATA_MAX_DEVICES; i++) {
3193 		struct ata_device *dev = &ap->device[i];
3194 		struct scsi_device *sdev = dev->sdev;
3195 
3196 		if (!ata_dev_enabled(dev) || !sdev)
3197 			continue;
3198 		if (scsi_device_get(sdev))
3199 			continue;
3200 
3201 		spin_unlock_irqrestore(ap->lock, flags);
3202 		scsi_rescan_device(&(sdev->sdev_gendev));
3203 		scsi_device_put(sdev);
3204 		spin_lock_irqsave(ap->lock, flags);
3205 	}
3206 
3207 	spin_unlock_irqrestore(ap->lock, flags);
3208 }
3209 
3210 /**
3211  *	ata_sas_port_alloc - Allocate port for a SAS attached SATA device
3212  *	@host: ATA host container for all SAS ports
3213  *	@port_info: Information from low-level host driver
3214  *	@shost: SCSI host that the scsi device is attached to
3215  *
3216  *	LOCKING:
3217  *	PCI/etc. bus probe sem.
3218  *
3219  *	RETURNS:
3220  *	ata_port pointer on success / NULL on failure.
3221  */
3222 
3223 struct ata_port *ata_sas_port_alloc(struct ata_host *host,
3224 				    struct ata_port_info *port_info,
3225 				    struct Scsi_Host *shost)
3226 {
3227 	struct ata_port *ap = kzalloc(sizeof(*ap), GFP_KERNEL);
3228 	struct ata_probe_ent *ent;
3229 
3230 	if (!ap)
3231 		return NULL;
3232 
3233 	ent = ata_probe_ent_alloc(host->dev, port_info);
3234 	if (!ent) {
3235 		kfree(ap);
3236 		return NULL;
3237 	}
3238 
3239 	ata_port_init(ap, host, ent, 0);
3240 	ap->lock = shost->host_lock;
3241 	devm_kfree(host->dev, ent);
3242 	return ap;
3243 }
3244 EXPORT_SYMBOL_GPL(ata_sas_port_alloc);
3245 
3246 /**
3247  *	ata_sas_port_start - Set port up for dma.
3248  *	@ap: Port to initialize
3249  *
3250  *	Called just after data structures for each port are
3251  *	initialized.  Allocates DMA pad.
3252  *
3253  *	May be used as the port_start() entry in ata_port_operations.
3254  *
3255  *	LOCKING:
3256  *	Inherited from caller.
3257  */
3258 int ata_sas_port_start(struct ata_port *ap)
3259 {
3260 	return ata_pad_alloc(ap, ap->dev);
3261 }
3262 EXPORT_SYMBOL_GPL(ata_sas_port_start);
3263 
3264 /**
3265  *	ata_port_stop - Undo ata_sas_port_start()
3266  *	@ap: Port to shut down
3267  *
3268  *	Frees the DMA pad.
3269  *
3270  *	May be used as the port_stop() entry in ata_port_operations.
3271  *
3272  *	LOCKING:
3273  *	Inherited from caller.
3274  */
3275 
3276 void ata_sas_port_stop(struct ata_port *ap)
3277 {
3278 	ata_pad_free(ap, ap->dev);
3279 }
3280 EXPORT_SYMBOL_GPL(ata_sas_port_stop);
3281 
3282 /**
3283  *	ata_sas_port_init - Initialize a SATA device
3284  *	@ap: SATA port to initialize
3285  *
3286  *	LOCKING:
3287  *	PCI/etc. bus probe sem.
3288  *
3289  *	RETURNS:
3290  *	Zero on success, non-zero on error.
3291  */
3292 
3293 int ata_sas_port_init(struct ata_port *ap)
3294 {
3295 	int rc = ap->ops->port_start(ap);
3296 
3297 	if (!rc)
3298 		rc = ata_bus_probe(ap);
3299 
3300 	return rc;
3301 }
3302 EXPORT_SYMBOL_GPL(ata_sas_port_init);
3303 
3304 /**
3305  *	ata_sas_port_destroy - Destroy a SATA port allocated by ata_sas_port_alloc
3306  *	@ap: SATA port to destroy
3307  *
3308  */
3309 
3310 void ata_sas_port_destroy(struct ata_port *ap)
3311 {
3312 	if (ap->ops->port_stop)
3313 		ap->ops->port_stop(ap);
3314 	kfree(ap);
3315 }
3316 EXPORT_SYMBOL_GPL(ata_sas_port_destroy);
3317 
3318 /**
3319  *	ata_sas_slave_configure - Default slave_config routine for libata devices
3320  *	@sdev: SCSI device to configure
3321  *	@ap: ATA port to which SCSI device is attached
3322  *
3323  *	RETURNS:
3324  *	Zero.
3325  */
3326 
3327 int ata_sas_slave_configure(struct scsi_device *sdev, struct ata_port *ap)
3328 {
3329 	ata_scsi_sdev_config(sdev);
3330 	ata_scsi_dev_config(sdev, ap->device);
3331 	return 0;
3332 }
3333 EXPORT_SYMBOL_GPL(ata_sas_slave_configure);
3334 
3335 /**
3336  *	ata_sas_queuecmd - Issue SCSI cdb to libata-managed device
3337  *	@cmd: SCSI command to be sent
3338  *	@done: Completion function, called when command is complete
3339  *	@ap:	ATA port to which the command is being sent
3340  *
3341  *	RETURNS:
3342  *	Return value from __ata_scsi_queuecmd() if @cmd can be queued,
3343  *	0 otherwise.
3344  */
3345 
3346 int ata_sas_queuecmd(struct scsi_cmnd *cmd, void (*done)(struct scsi_cmnd *),
3347 		     struct ata_port *ap)
3348 {
3349 	int rc = 0;
3350 
3351 	ata_scsi_dump_cdb(ap, cmd);
3352 
3353 	if (likely(ata_scsi_dev_enabled(ap->device)))
3354 		rc = __ata_scsi_queuecmd(cmd, done, ap->device);
3355 	else {
3356 		cmd->result = (DID_BAD_TARGET << 16);
3357 		done(cmd);
3358 	}
3359 	return rc;
3360 }
3361 EXPORT_SYMBOL_GPL(ata_sas_queuecmd);
3362