xref: /linux/drivers/ata/libata-scsi.c (revision b454cc6636d254fbf6049b73e9560aee76fb04a3)
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_cmd_ioctl - Handler for HDIO_DRIVE_CMD ioctl
153  *	@scsidev: Device to which we are issuing command
154  *	@arg: User provided data for issuing command
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 
163 int ata_cmd_ioctl(struct scsi_device *scsidev, void __user *arg)
164 {
165 	int rc = 0;
166 	u8 scsi_cmd[MAX_COMMAND_SIZE];
167 	u8 args[4], *argbuf = NULL, *sensebuf = NULL;
168 	int argsize = 0;
169 	enum dma_data_direction data_dir;
170 	int cmd_result;
171 
172 	if (arg == NULL)
173 		return -EINVAL;
174 
175 	if (copy_from_user(args, arg, sizeof(args)))
176 		return -EFAULT;
177 
178 	sensebuf = kzalloc(SCSI_SENSE_BUFFERSIZE, GFP_NOIO);
179 	if (!sensebuf)
180 		return -ENOMEM;
181 
182 	memset(scsi_cmd, 0, sizeof(scsi_cmd));
183 
184 	if (args[3]) {
185 		argsize = SECTOR_SIZE * args[3];
186 		argbuf = kmalloc(argsize, GFP_KERNEL);
187 		if (argbuf == NULL) {
188 			rc = -ENOMEM;
189 			goto error;
190 		}
191 
192 		scsi_cmd[1]  = (4 << 1); /* PIO Data-in */
193 		scsi_cmd[2]  = 0x0e;     /* no off.line or cc, read from dev,
194 		                            block count in sector count field */
195 		data_dir = DMA_FROM_DEVICE;
196 	} else {
197 		scsi_cmd[1]  = (3 << 1); /* Non-data */
198 		scsi_cmd[2]  = 0x20;     /* cc but no off.line or data xfer */
199 		data_dir = DMA_NONE;
200 	}
201 
202 	scsi_cmd[0] = ATA_16;
203 
204 	scsi_cmd[4] = args[2];
205 	if (args[0] == WIN_SMART) { /* hack -- ide driver does this too... */
206 		scsi_cmd[6]  = args[3];
207 		scsi_cmd[8]  = args[1];
208 		scsi_cmd[10] = 0x4f;
209 		scsi_cmd[12] = 0xc2;
210 	} else {
211 		scsi_cmd[6]  = args[1];
212 	}
213 	scsi_cmd[14] = args[0];
214 
215 	/* Good values for timeout and retries?  Values below
216 	   from scsi_ioctl_send_command() for default case... */
217 	cmd_result = scsi_execute(scsidev, scsi_cmd, data_dir, argbuf, argsize,
218 	                          sensebuf, (10*HZ), 5, 0);
219 
220 	if (driver_byte(cmd_result) == DRIVER_SENSE) {/* sense data available */
221 		u8 *desc = sensebuf + 8;
222 		cmd_result &= ~(0xFF<<24); /* DRIVER_SENSE is not an error */
223 
224 		/* If we set cc then ATA pass-through will cause a
225 		 * check condition even if no error. Filter that. */
226 		if (cmd_result & SAM_STAT_CHECK_CONDITION) {
227 			struct scsi_sense_hdr sshdr;
228 			scsi_normalize_sense(sensebuf, SCSI_SENSE_BUFFERSIZE,
229 			                      &sshdr);
230 			if (sshdr.sense_key==0 &&
231 			    sshdr.asc==0 && sshdr.ascq==0)
232 				cmd_result &= ~SAM_STAT_CHECK_CONDITION;
233 		}
234 
235 		/* Send userspace a few ATA registers (same as drivers/ide) */
236 		if (sensebuf[0] == 0x72 &&     /* format is "descriptor" */
237 		    desc[0] == 0x09 ) {        /* code is "ATA Descriptor" */
238 			args[0] = desc[13];    /* status */
239 			args[1] = desc[3];     /* error */
240 			args[2] = desc[5];     /* sector count (0:7) */
241 			if (copy_to_user(arg, args, sizeof(args)))
242 				rc = -EFAULT;
243 		}
244 	}
245 
246 
247 	if (cmd_result) {
248 		rc = -EIO;
249 		goto error;
250 	}
251 
252 	if ((argbuf)
253 	 && copy_to_user(arg + sizeof(args), argbuf, argsize))
254 		rc = -EFAULT;
255 error:
256 	kfree(sensebuf);
257 	kfree(argbuf);
258 	return rc;
259 }
260 
261 /**
262  *	ata_task_ioctl - Handler for HDIO_DRIVE_TASK ioctl
263  *	@scsidev: Device to which we are issuing command
264  *	@arg: User provided data for issuing command
265  *
266  *	LOCKING:
267  *	Defined by the SCSI layer.  We don't really care.
268  *
269  *	RETURNS:
270  *	Zero on success, negative errno on error.
271  */
272 int ata_task_ioctl(struct scsi_device *scsidev, void __user *arg)
273 {
274 	int rc = 0;
275 	u8 scsi_cmd[MAX_COMMAND_SIZE];
276 	u8 args[7], *sensebuf = NULL;
277 	int cmd_result;
278 
279 	if (arg == NULL)
280 		return -EINVAL;
281 
282 	if (copy_from_user(args, arg, sizeof(args)))
283 		return -EFAULT;
284 
285 	sensebuf = kzalloc(SCSI_SENSE_BUFFERSIZE, GFP_NOIO);
286 	if (!sensebuf)
287 		return -ENOMEM;
288 
289 	memset(scsi_cmd, 0, sizeof(scsi_cmd));
290 	scsi_cmd[0]  = ATA_16;
291 	scsi_cmd[1]  = (3 << 1); /* Non-data */
292 	scsi_cmd[2]  = 0x20;     /* cc but no off.line or data xfer */
293 	scsi_cmd[4]  = args[1];
294 	scsi_cmd[6]  = args[2];
295 	scsi_cmd[8]  = args[3];
296 	scsi_cmd[10] = args[4];
297 	scsi_cmd[12] = args[5];
298 	scsi_cmd[14] = args[0];
299 
300 	/* Good values for timeout and retries?  Values below
301 	   from scsi_ioctl_send_command() for default case... */
302 	cmd_result = scsi_execute(scsidev, scsi_cmd, DMA_NONE, NULL, 0,
303 				sensebuf, (10*HZ), 5, 0);
304 
305 	if (driver_byte(cmd_result) == DRIVER_SENSE) {/* sense data available */
306 		u8 *desc = sensebuf + 8;
307 		cmd_result &= ~(0xFF<<24); /* DRIVER_SENSE is not an error */
308 
309 		/* If we set cc then ATA pass-through will cause a
310 		 * check condition even if no error. Filter that. */
311 		if (cmd_result & SAM_STAT_CHECK_CONDITION) {
312 			struct scsi_sense_hdr sshdr;
313 			scsi_normalize_sense(sensebuf, SCSI_SENSE_BUFFERSIZE,
314 						&sshdr);
315 			if (sshdr.sense_key==0 &&
316 				sshdr.asc==0 && sshdr.ascq==0)
317 				cmd_result &= ~SAM_STAT_CHECK_CONDITION;
318 		}
319 
320 		/* Send userspace ATA registers */
321 		if (sensebuf[0] == 0x72 &&	/* format is "descriptor" */
322 				desc[0] == 0x09) {/* code is "ATA Descriptor" */
323 			args[0] = desc[13];	/* status */
324 			args[1] = desc[3];	/* error */
325 			args[2] = desc[5];	/* sector count (0:7) */
326 			args[3] = desc[7];	/* lbal */
327 			args[4] = desc[9];	/* lbam */
328 			args[5] = desc[11];	/* lbah */
329 			args[6] = desc[12];	/* select */
330 			if (copy_to_user(arg, args, sizeof(args)))
331 				rc = -EFAULT;
332 		}
333 	}
334 
335 	if (cmd_result) {
336 		rc = -EIO;
337 		goto error;
338 	}
339 
340  error:
341 	kfree(sensebuf);
342 	return rc;
343 }
344 
345 int ata_scsi_ioctl(struct scsi_device *scsidev, int cmd, void __user *arg)
346 {
347 	int val = -EINVAL, rc = -EINVAL;
348 
349 	switch (cmd) {
350 	case ATA_IOC_GET_IO32:
351 		val = 0;
352 		if (copy_to_user(arg, &val, 1))
353 			return -EFAULT;
354 		return 0;
355 
356 	case ATA_IOC_SET_IO32:
357 		val = (unsigned long) arg;
358 		if (val != 0)
359 			return -EINVAL;
360 		return 0;
361 
362 	case HDIO_DRIVE_CMD:
363 		if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
364 			return -EACCES;
365 		return ata_cmd_ioctl(scsidev, arg);
366 
367 	case HDIO_DRIVE_TASK:
368 		if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
369 			return -EACCES;
370 		return ata_task_ioctl(scsidev, arg);
371 
372 	default:
373 		rc = -ENOTTY;
374 		break;
375 	}
376 
377 	return rc;
378 }
379 
380 /**
381  *	ata_scsi_qc_new - acquire new ata_queued_cmd reference
382  *	@dev: ATA device to which the new command is attached
383  *	@cmd: SCSI command that originated this ATA command
384  *	@done: SCSI command completion function
385  *
386  *	Obtain a reference to an unused ata_queued_cmd structure,
387  *	which is the basic libata structure representing a single
388  *	ATA command sent to the hardware.
389  *
390  *	If a command was available, fill in the SCSI-specific
391  *	portions of the structure with information on the
392  *	current command.
393  *
394  *	LOCKING:
395  *	spin_lock_irqsave(host lock)
396  *
397  *	RETURNS:
398  *	Command allocated, or %NULL if none available.
399  */
400 struct ata_queued_cmd *ata_scsi_qc_new(struct ata_device *dev,
401 				       struct scsi_cmnd *cmd,
402 				       void (*done)(struct scsi_cmnd *))
403 {
404 	struct ata_queued_cmd *qc;
405 
406 	qc = ata_qc_new_init(dev);
407 	if (qc) {
408 		qc->scsicmd = cmd;
409 		qc->scsidone = done;
410 
411 		if (cmd->use_sg) {
412 			qc->__sg = (struct scatterlist *) cmd->request_buffer;
413 			qc->n_elem = cmd->use_sg;
414 		} else if (cmd->request_bufflen) {
415 			qc->__sg = &qc->sgent;
416 			qc->n_elem = 1;
417 		}
418 	} else {
419 		cmd->result = (DID_OK << 16) | (QUEUE_FULL << 1);
420 		done(cmd);
421 	}
422 
423 	return qc;
424 }
425 
426 /**
427  *	ata_dump_status - user friendly display of error info
428  *	@id: id of the port in question
429  *	@tf: ptr to filled out taskfile
430  *
431  *	Decode and dump the ATA error/status registers for the user so
432  *	that they have some idea what really happened at the non
433  *	make-believe layer.
434  *
435  *	LOCKING:
436  *	inherited from caller
437  */
438 void ata_dump_status(unsigned id, struct ata_taskfile *tf)
439 {
440 	u8 stat = tf->command, err = tf->feature;
441 
442 	printk(KERN_WARNING "ata%u: status=0x%02x { ", id, stat);
443 	if (stat & ATA_BUSY) {
444 		printk("Busy }\n");	/* Data is not valid in this case */
445 	} else {
446 		if (stat & 0x40)	printk("DriveReady ");
447 		if (stat & 0x20)	printk("DeviceFault ");
448 		if (stat & 0x10)	printk("SeekComplete ");
449 		if (stat & 0x08)	printk("DataRequest ");
450 		if (stat & 0x04)	printk("CorrectedError ");
451 		if (stat & 0x02)	printk("Index ");
452 		if (stat & 0x01)	printk("Error ");
453 		printk("}\n");
454 
455 		if (err) {
456 			printk(KERN_WARNING "ata%u: error=0x%02x { ", id, err);
457 			if (err & 0x04)		printk("DriveStatusError ");
458 			if (err & 0x80) {
459 				if (err & 0x04)	printk("BadCRC ");
460 				else		printk("Sector ");
461 			}
462 			if (err & 0x40)		printk("UncorrectableError ");
463 			if (err & 0x10)		printk("SectorIdNotFound ");
464 			if (err & 0x02)		printk("TrackZeroNotFound ");
465 			if (err & 0x01)		printk("AddrMarkNotFound ");
466 			printk("}\n");
467 		}
468 	}
469 }
470 
471 /**
472  *	ata_scsi_device_suspend - suspend ATA device associated with sdev
473  *	@sdev: the SCSI device to suspend
474  *	@mesg: target power management message
475  *
476  *	Request suspend EH action on the ATA device associated with
477  *	@sdev and wait for the operation to complete.
478  *
479  *	LOCKING:
480  *	Kernel thread context (may sleep).
481  *
482  *	RETURNS:
483  *	0 on success, -errno otherwise.
484  */
485 int ata_scsi_device_suspend(struct scsi_device *sdev, pm_message_t mesg)
486 {
487 	struct ata_port *ap = ata_shost_to_port(sdev->host);
488 	struct ata_device *dev = ata_scsi_find_dev(ap, sdev);
489 	unsigned long flags;
490 	unsigned int action;
491 	int rc = 0;
492 
493 	if (!dev)
494 		goto out;
495 
496 	spin_lock_irqsave(ap->lock, flags);
497 
498 	/* wait for the previous resume to complete */
499 	while (dev->flags & ATA_DFLAG_SUSPENDED) {
500 		spin_unlock_irqrestore(ap->lock, flags);
501 		ata_port_wait_eh(ap);
502 		spin_lock_irqsave(ap->lock, flags);
503 	}
504 
505 	/* if @sdev is already detached, nothing to do */
506 	if (sdev->sdev_state == SDEV_OFFLINE ||
507 	    sdev->sdev_state == SDEV_CANCEL || sdev->sdev_state == SDEV_DEL)
508 		goto out_unlock;
509 
510 	/* request suspend */
511 	action = ATA_EH_SUSPEND;
512 	if (mesg.event != PM_EVENT_SUSPEND)
513 		action |= ATA_EH_PM_FREEZE;
514 	ap->eh_info.dev_action[dev->devno] |= action;
515 	ap->eh_info.flags |= ATA_EHI_QUIET;
516 	ata_port_schedule_eh(ap);
517 
518 	spin_unlock_irqrestore(ap->lock, flags);
519 
520 	/* wait for EH to do the job */
521 	ata_port_wait_eh(ap);
522 
523 	spin_lock_irqsave(ap->lock, flags);
524 
525 	/* If @sdev is still attached but the associated ATA device
526 	 * isn't suspended, the operation failed.
527 	 */
528 	if (sdev->sdev_state != SDEV_OFFLINE &&
529 	    sdev->sdev_state != SDEV_CANCEL && sdev->sdev_state != SDEV_DEL &&
530 	    !(dev->flags & ATA_DFLAG_SUSPENDED))
531 		rc = -EIO;
532 
533  out_unlock:
534 	spin_unlock_irqrestore(ap->lock, flags);
535  out:
536 	if (rc == 0)
537 		sdev->sdev_gendev.power.power_state = mesg;
538 	return rc;
539 }
540 
541 /**
542  *	ata_scsi_device_resume - resume ATA device associated with sdev
543  *	@sdev: the SCSI device to resume
544  *
545  *	Request resume EH action on the ATA device associated with
546  *	@sdev and return immediately.  This enables parallel
547  *	wakeup/spinup of devices.
548  *
549  *	LOCKING:
550  *	Kernel thread context (may sleep).
551  *
552  *	RETURNS:
553  *	0.
554  */
555 int ata_scsi_device_resume(struct scsi_device *sdev)
556 {
557 	struct ata_port *ap = ata_shost_to_port(sdev->host);
558 	struct ata_device *dev = ata_scsi_find_dev(ap, sdev);
559 	struct ata_eh_info *ehi = &ap->eh_info;
560 	unsigned long flags;
561 	unsigned int action;
562 
563 	if (!dev)
564 		goto out;
565 
566 	spin_lock_irqsave(ap->lock, flags);
567 
568 	/* if @sdev is already detached, nothing to do */
569 	if (sdev->sdev_state == SDEV_OFFLINE ||
570 	    sdev->sdev_state == SDEV_CANCEL || sdev->sdev_state == SDEV_DEL)
571 		goto out_unlock;
572 
573 	/* request resume */
574 	action = ATA_EH_RESUME;
575 	if (sdev->sdev_gendev.power.power_state.event == PM_EVENT_SUSPEND)
576 		__ata_ehi_hotplugged(ehi);
577 	else
578 		action |= ATA_EH_PM_FREEZE | ATA_EH_SOFTRESET;
579 	ehi->dev_action[dev->devno] |= action;
580 
581 	/* We don't want autopsy and verbose EH messages.  Disable
582 	 * those if we're the only device on this link.
583 	 */
584 	if (ata_port_max_devices(ap) == 1)
585 		ehi->flags |= ATA_EHI_NO_AUTOPSY | ATA_EHI_QUIET;
586 
587 	ata_port_schedule_eh(ap);
588 
589  out_unlock:
590 	spin_unlock_irqrestore(ap->lock, flags);
591  out:
592 	sdev->sdev_gendev.power.power_state = PMSG_ON;
593 	return 0;
594 }
595 
596 /**
597  *	ata_to_sense_error - convert ATA error to SCSI error
598  *	@id: ATA device number
599  *	@drv_stat: value contained in ATA status register
600  *	@drv_err: value contained in ATA error register
601  *	@sk: the sense key we'll fill out
602  *	@asc: the additional sense code we'll fill out
603  *	@ascq: the additional sense code qualifier we'll fill out
604  *	@verbose: be verbose
605  *
606  *	Converts an ATA error into a SCSI error.  Fill out pointers to
607  *	SK, ASC, and ASCQ bytes for later use in fixed or descriptor
608  *	format sense blocks.
609  *
610  *	LOCKING:
611  *	spin_lock_irqsave(host lock)
612  */
613 void ata_to_sense_error(unsigned id, u8 drv_stat, u8 drv_err, u8 *sk, u8 *asc,
614 			u8 *ascq, int verbose)
615 {
616 	int i;
617 
618 	/* Based on the 3ware driver translation table */
619 	static const unsigned char sense_table[][4] = {
620 		/* BBD|ECC|ID|MAR */
621 		{0xd1, 		ABORTED_COMMAND, 0x00, 0x00}, 	// Device busy                  Aborted command
622 		/* BBD|ECC|ID */
623 		{0xd0,  	ABORTED_COMMAND, 0x00, 0x00}, 	// Device busy                  Aborted command
624 		/* ECC|MC|MARK */
625 		{0x61, 		HARDWARE_ERROR, 0x00, 0x00}, 	// Device fault                 Hardware error
626 		/* ICRC|ABRT */		/* NB: ICRC & !ABRT is BBD */
627 		{0x84, 		ABORTED_COMMAND, 0x47, 0x00}, 	// Data CRC error               SCSI parity error
628 		/* MC|ID|ABRT|TRK0|MARK */
629 		{0x37, 		NOT_READY, 0x04, 0x00}, 	// Unit offline                 Not ready
630 		/* MCR|MARK */
631 		{0x09, 		NOT_READY, 0x04, 0x00}, 	// Unrecovered disk error       Not ready
632 		/*  Bad address mark */
633 		{0x01, 		MEDIUM_ERROR, 0x13, 0x00}, 	// Address mark not found       Address mark not found for data field
634 		/* TRK0 */
635 		{0x02, 		HARDWARE_ERROR, 0x00, 0x00}, 	// Track 0 not found		  Hardware error
636 		/* Abort & !ICRC */
637 		{0x04, 		ABORTED_COMMAND, 0x00, 0x00}, 	// Aborted command              Aborted command
638 		/* Media change request */
639 		{0x08, 		NOT_READY, 0x04, 0x00}, 	// Media change request	  FIXME: faking offline
640 		/* SRV */
641 		{0x10, 		ABORTED_COMMAND, 0x14, 0x00}, 	// ID not found                 Recorded entity not found
642 		/* Media change */
643 		{0x08,  	NOT_READY, 0x04, 0x00}, 	// Media change		  FIXME: faking offline
644 		/* ECC */
645 		{0x40, 		MEDIUM_ERROR, 0x11, 0x04}, 	// Uncorrectable ECC error      Unrecovered read error
646 		/* BBD - block marked bad */
647 		{0x80, 		MEDIUM_ERROR, 0x11, 0x04}, 	// Block marked bad		  Medium error, unrecovered read error
648 		{0xFF, 0xFF, 0xFF, 0xFF}, // END mark
649 	};
650 	static const unsigned char stat_table[][4] = {
651 		/* Must be first because BUSY means no other bits valid */
652 		{0x80, 		ABORTED_COMMAND, 0x47, 0x00},	// Busy, fake parity for now
653 		{0x20, 		HARDWARE_ERROR,  0x00, 0x00}, 	// Device fault
654 		{0x08, 		ABORTED_COMMAND, 0x47, 0x00},	// Timed out in xfer, fake parity for now
655 		{0x04, 		RECOVERED_ERROR, 0x11, 0x00},	// Recovered ECC error	  Medium error, recovered
656 		{0xFF, 0xFF, 0xFF, 0xFF}, // END mark
657 	};
658 
659 	/*
660 	 *	Is this an error we can process/parse
661 	 */
662 	if (drv_stat & ATA_BUSY) {
663 		drv_err = 0;	/* Ignore the err bits, they're invalid */
664 	}
665 
666 	if (drv_err) {
667 		/* Look for drv_err */
668 		for (i = 0; sense_table[i][0] != 0xFF; i++) {
669 			/* Look for best matches first */
670 			if ((sense_table[i][0] & drv_err) ==
671 			    sense_table[i][0]) {
672 				*sk = sense_table[i][1];
673 				*asc = sense_table[i][2];
674 				*ascq = sense_table[i][3];
675 				goto translate_done;
676 			}
677 		}
678 		/* No immediate match */
679 		if (verbose)
680 			printk(KERN_WARNING "ata%u: no sense translation for "
681 			       "error 0x%02x\n", id, drv_err);
682 	}
683 
684 	/* Fall back to interpreting status bits */
685 	for (i = 0; stat_table[i][0] != 0xFF; i++) {
686 		if (stat_table[i][0] & drv_stat) {
687 			*sk = stat_table[i][1];
688 			*asc = stat_table[i][2];
689 			*ascq = stat_table[i][3];
690 			goto translate_done;
691 		}
692 	}
693 	/* No error?  Undecoded? */
694 	if (verbose)
695 		printk(KERN_WARNING "ata%u: no sense translation for "
696 		       "status: 0x%02x\n", id, drv_stat);
697 
698 	/* We need a sensible error return here, which is tricky, and one
699 	   that won't cause people to do things like return a disk wrongly */
700 	*sk = ABORTED_COMMAND;
701 	*asc = 0x00;
702 	*ascq = 0x00;
703 
704  translate_done:
705 	if (verbose)
706 		printk(KERN_ERR "ata%u: translated ATA stat/err 0x%02x/%02x "
707 		       "to SCSI SK/ASC/ASCQ 0x%x/%02x/%02x\n",
708 		       id, drv_stat, drv_err, *sk, *asc, *ascq);
709 	return;
710 }
711 
712 /*
713  *	ata_gen_passthru_sense - Generate check condition sense block.
714  *	@qc: Command that completed.
715  *
716  *	This function is specific to the ATA descriptor format sense
717  *	block specified for the ATA pass through commands.  Regardless
718  *	of whether the command errored or not, return a sense
719  *	block. Copy all controller registers into the sense
720  *	block. Clear sense key, ASC & ASCQ if there is no error.
721  *
722  *	LOCKING:
723  *	None.
724  */
725 static void ata_gen_passthru_sense(struct ata_queued_cmd *qc)
726 {
727 	struct scsi_cmnd *cmd = qc->scsicmd;
728 	struct ata_taskfile *tf = &qc->result_tf;
729 	unsigned char *sb = cmd->sense_buffer;
730 	unsigned char *desc = sb + 8;
731 	int verbose = qc->ap->ops->error_handler == NULL;
732 
733 	memset(sb, 0, SCSI_SENSE_BUFFERSIZE);
734 
735 	cmd->result = (DRIVER_SENSE << 24) | SAM_STAT_CHECK_CONDITION;
736 
737 	/*
738 	 * Use ata_to_sense_error() to map status register bits
739 	 * onto sense key, asc & ascq.
740 	 */
741 	if (qc->err_mask ||
742 	    tf->command & (ATA_BUSY | ATA_DF | ATA_ERR | ATA_DRQ)) {
743 		ata_to_sense_error(qc->ap->id, tf->command, tf->feature,
744 				   &sb[1], &sb[2], &sb[3], verbose);
745 		sb[1] &= 0x0f;
746 	}
747 
748 	/*
749 	 * Sense data is current and format is descriptor.
750 	 */
751 	sb[0] = 0x72;
752 
753 	desc[0] = 0x09;
754 
755 	/* set length of additional sense data */
756 	sb[7] = 14;
757 	desc[1] = 12;
758 
759 	/*
760 	 * Copy registers into sense buffer.
761 	 */
762 	desc[2] = 0x00;
763 	desc[3] = tf->feature;	/* == error reg */
764 	desc[5] = tf->nsect;
765 	desc[7] = tf->lbal;
766 	desc[9] = tf->lbam;
767 	desc[11] = tf->lbah;
768 	desc[12] = tf->device;
769 	desc[13] = tf->command; /* == status reg */
770 
771 	/*
772 	 * Fill in Extend bit, and the high order bytes
773 	 * if applicable.
774 	 */
775 	if (tf->flags & ATA_TFLAG_LBA48) {
776 		desc[2] |= 0x01;
777 		desc[4] = tf->hob_nsect;
778 		desc[6] = tf->hob_lbal;
779 		desc[8] = tf->hob_lbam;
780 		desc[10] = tf->hob_lbah;
781 	}
782 }
783 
784 /**
785  *	ata_gen_ata_sense - generate a SCSI fixed sense block
786  *	@qc: Command that we are erroring out
787  *
788  *	Generate sense block for a failed ATA command @qc.  Descriptor
789  *	format is used to accomodate LBA48 block address.
790  *
791  *	LOCKING:
792  *	None.
793  */
794 static void ata_gen_ata_sense(struct ata_queued_cmd *qc)
795 {
796 	struct ata_device *dev = qc->dev;
797 	struct scsi_cmnd *cmd = qc->scsicmd;
798 	struct ata_taskfile *tf = &qc->result_tf;
799 	unsigned char *sb = cmd->sense_buffer;
800 	unsigned char *desc = sb + 8;
801 	int verbose = qc->ap->ops->error_handler == NULL;
802 	u64 block;
803 
804 	memset(sb, 0, SCSI_SENSE_BUFFERSIZE);
805 
806 	cmd->result = (DRIVER_SENSE << 24) | SAM_STAT_CHECK_CONDITION;
807 
808 	/* sense data is current and format is descriptor */
809 	sb[0] = 0x72;
810 
811 	/* Use ata_to_sense_error() to map status register bits
812 	 * onto sense key, asc & ascq.
813 	 */
814 	if (qc->err_mask ||
815 	    tf->command & (ATA_BUSY | ATA_DF | ATA_ERR | ATA_DRQ)) {
816 		ata_to_sense_error(qc->ap->id, tf->command, tf->feature,
817 				   &sb[1], &sb[2], &sb[3], verbose);
818 		sb[1] &= 0x0f;
819 	}
820 
821 	block = ata_tf_read_block(&qc->result_tf, dev);
822 
823 	/* information sense data descriptor */
824 	sb[7] = 12;
825 	desc[0] = 0x00;
826 	desc[1] = 10;
827 
828 	desc[2] |= 0x80;	/* valid */
829 	desc[6] = block >> 40;
830 	desc[7] = block >> 32;
831 	desc[8] = block >> 24;
832 	desc[9] = block >> 16;
833 	desc[10] = block >> 8;
834 	desc[11] = block;
835 }
836 
837 static void ata_scsi_sdev_config(struct scsi_device *sdev)
838 {
839 	sdev->use_10_for_rw = 1;
840 	sdev->use_10_for_ms = 1;
841 }
842 
843 static void ata_scsi_dev_config(struct scsi_device *sdev,
844 				struct ata_device *dev)
845 {
846 	/* configure max sectors */
847 	blk_queue_max_sectors(sdev->request_queue, dev->max_sectors);
848 
849 	/* SATA DMA transfers must be multiples of 4 byte, so
850 	 * we need to pad ATAPI transfers using an extra sg.
851 	 * Decrement max hw segments accordingly.
852 	 */
853 	if (dev->class == ATA_DEV_ATAPI) {
854 		request_queue_t *q = sdev->request_queue;
855 		blk_queue_max_hw_segments(q, q->max_hw_segments - 1);
856 	}
857 
858 	if (dev->flags & ATA_DFLAG_NCQ) {
859 		int depth;
860 
861 		depth = min(sdev->host->can_queue, ata_id_queue_depth(dev->id));
862 		depth = min(ATA_MAX_QUEUE - 1, depth);
863 		scsi_adjust_queue_depth(sdev, MSG_SIMPLE_TAG, depth);
864 	}
865 }
866 
867 /**
868  *	ata_scsi_slave_config - Set SCSI device attributes
869  *	@sdev: SCSI device to examine
870  *
871  *	This is called before we actually start reading
872  *	and writing to the device, to configure certain
873  *	SCSI mid-layer behaviors.
874  *
875  *	LOCKING:
876  *	Defined by SCSI layer.  We don't really care.
877  */
878 
879 int ata_scsi_slave_config(struct scsi_device *sdev)
880 {
881 	struct ata_port *ap = ata_shost_to_port(sdev->host);
882 	struct ata_device *dev = __ata_scsi_find_dev(ap, sdev);
883 
884 	ata_scsi_sdev_config(sdev);
885 
886 	blk_queue_max_phys_segments(sdev->request_queue, LIBATA_MAX_PRD);
887 
888 	if (dev)
889 		ata_scsi_dev_config(sdev, dev);
890 
891 	return 0;	/* scsi layer doesn't check return value, sigh */
892 }
893 
894 /**
895  *	ata_scsi_slave_destroy - SCSI device is about to be destroyed
896  *	@sdev: SCSI device to be destroyed
897  *
898  *	@sdev is about to be destroyed for hot/warm unplugging.  If
899  *	this unplugging was initiated by libata as indicated by NULL
900  *	dev->sdev, this function doesn't have to do anything.
901  *	Otherwise, SCSI layer initiated warm-unplug is in progress.
902  *	Clear dev->sdev, schedule the device for ATA detach and invoke
903  *	EH.
904  *
905  *	LOCKING:
906  *	Defined by SCSI layer.  We don't really care.
907  */
908 void ata_scsi_slave_destroy(struct scsi_device *sdev)
909 {
910 	struct ata_port *ap = ata_shost_to_port(sdev->host);
911 	unsigned long flags;
912 	struct ata_device *dev;
913 
914 	if (!ap->ops->error_handler)
915 		return;
916 
917 	spin_lock_irqsave(ap->lock, flags);
918 	dev = __ata_scsi_find_dev(ap, sdev);
919 	if (dev && dev->sdev) {
920 		/* SCSI device already in CANCEL state, no need to offline it */
921 		dev->sdev = NULL;
922 		dev->flags |= ATA_DFLAG_DETACH;
923 		ata_port_schedule_eh(ap);
924 	}
925 	spin_unlock_irqrestore(ap->lock, flags);
926 }
927 
928 /**
929  *	ata_scsi_change_queue_depth - SCSI callback for queue depth config
930  *	@sdev: SCSI device to configure queue depth for
931  *	@queue_depth: new queue depth
932  *
933  *	This is libata standard hostt->change_queue_depth callback.
934  *	SCSI will call into this callback when user tries to set queue
935  *	depth via sysfs.
936  *
937  *	LOCKING:
938  *	SCSI layer (we don't care)
939  *
940  *	RETURNS:
941  *	Newly configured queue depth.
942  */
943 int ata_scsi_change_queue_depth(struct scsi_device *sdev, int queue_depth)
944 {
945 	struct ata_port *ap = ata_shost_to_port(sdev->host);
946 	struct ata_device *dev;
947 	unsigned long flags;
948 	int max_depth;
949 
950 	if (queue_depth < 1)
951 		return sdev->queue_depth;
952 
953 	dev = ata_scsi_find_dev(ap, sdev);
954 	if (!dev || !ata_dev_enabled(dev))
955 		return sdev->queue_depth;
956 
957 	max_depth = min(sdev->host->can_queue, ata_id_queue_depth(dev->id));
958 	max_depth = min(ATA_MAX_QUEUE - 1, max_depth);
959 	if (queue_depth > max_depth)
960 		queue_depth = max_depth;
961 
962 	scsi_adjust_queue_depth(sdev, MSG_SIMPLE_TAG, queue_depth);
963 
964 	spin_lock_irqsave(ap->lock, flags);
965 	if (queue_depth > 1)
966 		dev->flags &= ~ATA_DFLAG_NCQ_OFF;
967 	else
968 		dev->flags |= ATA_DFLAG_NCQ_OFF;
969 	spin_unlock_irqrestore(ap->lock, flags);
970 
971 	return queue_depth;
972 }
973 
974 /**
975  *	ata_scsi_start_stop_xlat - Translate SCSI START STOP UNIT command
976  *	@qc: Storage for translated ATA taskfile
977  *
978  *	Sets up an ATA taskfile to issue STANDBY (to stop) or READ VERIFY
979  *	(to start). Perhaps these commands should be preceded by
980  *	CHECK POWER MODE to see what power mode the device is already in.
981  *	[See SAT revision 5 at www.t10.org]
982  *
983  *	LOCKING:
984  *	spin_lock_irqsave(host lock)
985  *
986  *	RETURNS:
987  *	Zero on success, non-zero on error.
988  */
989 static unsigned int ata_scsi_start_stop_xlat(struct ata_queued_cmd *qc)
990 {
991 	struct scsi_cmnd *scmd = qc->scsicmd;
992 	struct ata_taskfile *tf = &qc->tf;
993 	const u8 *cdb = scmd->cmnd;
994 
995 	if (scmd->cmd_len < 5)
996 		goto invalid_fld;
997 
998 	tf->flags |= ATA_TFLAG_DEVICE | ATA_TFLAG_ISADDR;
999 	tf->protocol = ATA_PROT_NODATA;
1000 	if (cdb[1] & 0x1) {
1001 		;	/* ignore IMMED bit, violates sat-r05 */
1002 	}
1003 	if (cdb[4] & 0x2)
1004 		goto invalid_fld;       /* LOEJ bit set not supported */
1005 	if (((cdb[4] >> 4) & 0xf) != 0)
1006 		goto invalid_fld;       /* power conditions not supported */
1007 	if (cdb[4] & 0x1) {
1008 		tf->nsect = 1;	/* 1 sector, lba=0 */
1009 
1010 		if (qc->dev->flags & ATA_DFLAG_LBA) {
1011 			tf->flags |= ATA_TFLAG_LBA;
1012 
1013 			tf->lbah = 0x0;
1014 			tf->lbam = 0x0;
1015 			tf->lbal = 0x0;
1016 			tf->device |= ATA_LBA;
1017 		} else {
1018 			/* CHS */
1019 			tf->lbal = 0x1; /* sect */
1020 			tf->lbam = 0x0; /* cyl low */
1021 			tf->lbah = 0x0; /* cyl high */
1022 		}
1023 
1024 		tf->command = ATA_CMD_VERIFY;	/* READ VERIFY */
1025 	} else
1026 		/* Issue ATA STANDBY IMMEDIATE command */
1027 		tf->command = ATA_CMD_STANDBYNOW1;
1028 
1029 	/*
1030 	 * Standby and Idle condition timers could be implemented but that
1031 	 * would require libata to implement the Power condition mode page
1032 	 * and allow the user to change it. Changing mode pages requires
1033 	 * MODE SELECT to be implemented.
1034 	 */
1035 
1036 	return 0;
1037 
1038 invalid_fld:
1039 	ata_scsi_set_sense(scmd, ILLEGAL_REQUEST, 0x24, 0x0);
1040 	/* "Invalid field in cbd" */
1041 	return 1;
1042 }
1043 
1044 
1045 /**
1046  *	ata_scsi_flush_xlat - Translate SCSI SYNCHRONIZE CACHE command
1047  *	@qc: Storage for translated ATA taskfile
1048  *
1049  *	Sets up an ATA taskfile to issue FLUSH CACHE or
1050  *	FLUSH CACHE EXT.
1051  *
1052  *	LOCKING:
1053  *	spin_lock_irqsave(host lock)
1054  *
1055  *	RETURNS:
1056  *	Zero on success, non-zero on error.
1057  */
1058 static unsigned int ata_scsi_flush_xlat(struct ata_queued_cmd *qc)
1059 {
1060 	struct ata_taskfile *tf = &qc->tf;
1061 
1062 	tf->flags |= ATA_TFLAG_DEVICE;
1063 	tf->protocol = ATA_PROT_NODATA;
1064 
1065 	if (qc->dev->flags & ATA_DFLAG_FLUSH_EXT)
1066 		tf->command = ATA_CMD_FLUSH_EXT;
1067 	else
1068 		tf->command = ATA_CMD_FLUSH;
1069 
1070 	return 0;
1071 }
1072 
1073 /**
1074  *	scsi_6_lba_len - Get LBA and transfer length
1075  *	@cdb: SCSI command to translate
1076  *
1077  *	Calculate LBA and transfer length for 6-byte commands.
1078  *
1079  *	RETURNS:
1080  *	@plba: the LBA
1081  *	@plen: the transfer length
1082  */
1083 static void scsi_6_lba_len(const u8 *cdb, u64 *plba, u32 *plen)
1084 {
1085 	u64 lba = 0;
1086 	u32 len = 0;
1087 
1088 	VPRINTK("six-byte command\n");
1089 
1090 	lba |= ((u64)cdb[2]) << 8;
1091 	lba |= ((u64)cdb[3]);
1092 
1093 	len |= ((u32)cdb[4]);
1094 
1095 	*plba = lba;
1096 	*plen = len;
1097 }
1098 
1099 /**
1100  *	scsi_10_lba_len - Get LBA and transfer length
1101  *	@cdb: SCSI command to translate
1102  *
1103  *	Calculate LBA and transfer length for 10-byte commands.
1104  *
1105  *	RETURNS:
1106  *	@plba: the LBA
1107  *	@plen: the transfer length
1108  */
1109 static void scsi_10_lba_len(const u8 *cdb, u64 *plba, u32 *plen)
1110 {
1111 	u64 lba = 0;
1112 	u32 len = 0;
1113 
1114 	VPRINTK("ten-byte command\n");
1115 
1116 	lba |= ((u64)cdb[2]) << 24;
1117 	lba |= ((u64)cdb[3]) << 16;
1118 	lba |= ((u64)cdb[4]) << 8;
1119 	lba |= ((u64)cdb[5]);
1120 
1121 	len |= ((u32)cdb[7]) << 8;
1122 	len |= ((u32)cdb[8]);
1123 
1124 	*plba = lba;
1125 	*plen = len;
1126 }
1127 
1128 /**
1129  *	scsi_16_lba_len - Get LBA and transfer length
1130  *	@cdb: SCSI command to translate
1131  *
1132  *	Calculate LBA and transfer length for 16-byte commands.
1133  *
1134  *	RETURNS:
1135  *	@plba: the LBA
1136  *	@plen: the transfer length
1137  */
1138 static void scsi_16_lba_len(const u8 *cdb, u64 *plba, u32 *plen)
1139 {
1140 	u64 lba = 0;
1141 	u32 len = 0;
1142 
1143 	VPRINTK("sixteen-byte command\n");
1144 
1145 	lba |= ((u64)cdb[2]) << 56;
1146 	lba |= ((u64)cdb[3]) << 48;
1147 	lba |= ((u64)cdb[4]) << 40;
1148 	lba |= ((u64)cdb[5]) << 32;
1149 	lba |= ((u64)cdb[6]) << 24;
1150 	lba |= ((u64)cdb[7]) << 16;
1151 	lba |= ((u64)cdb[8]) << 8;
1152 	lba |= ((u64)cdb[9]);
1153 
1154 	len |= ((u32)cdb[10]) << 24;
1155 	len |= ((u32)cdb[11]) << 16;
1156 	len |= ((u32)cdb[12]) << 8;
1157 	len |= ((u32)cdb[13]);
1158 
1159 	*plba = lba;
1160 	*plen = len;
1161 }
1162 
1163 /**
1164  *	ata_scsi_verify_xlat - Translate SCSI VERIFY command into an ATA one
1165  *	@qc: Storage for translated ATA taskfile
1166  *
1167  *	Converts SCSI VERIFY command to an ATA READ VERIFY command.
1168  *
1169  *	LOCKING:
1170  *	spin_lock_irqsave(host lock)
1171  *
1172  *	RETURNS:
1173  *	Zero on success, non-zero on error.
1174  */
1175 static unsigned int ata_scsi_verify_xlat(struct ata_queued_cmd *qc)
1176 {
1177 	struct scsi_cmnd *scmd = qc->scsicmd;
1178 	struct ata_taskfile *tf = &qc->tf;
1179 	struct ata_device *dev = qc->dev;
1180 	u64 dev_sectors = qc->dev->n_sectors;
1181 	const u8 *cdb = scmd->cmnd;
1182 	u64 block;
1183 	u32 n_block;
1184 
1185 	tf->flags |= ATA_TFLAG_ISADDR | ATA_TFLAG_DEVICE;
1186 	tf->protocol = ATA_PROT_NODATA;
1187 
1188 	if (cdb[0] == VERIFY) {
1189 		if (scmd->cmd_len < 10)
1190 			goto invalid_fld;
1191 		scsi_10_lba_len(cdb, &block, &n_block);
1192 	} else if (cdb[0] == VERIFY_16) {
1193 		if (scmd->cmd_len < 16)
1194 			goto invalid_fld;
1195 		scsi_16_lba_len(cdb, &block, &n_block);
1196 	} else
1197 		goto invalid_fld;
1198 
1199 	if (!n_block)
1200 		goto nothing_to_do;
1201 	if (block >= dev_sectors)
1202 		goto out_of_range;
1203 	if ((block + n_block) > dev_sectors)
1204 		goto out_of_range;
1205 
1206 	if (dev->flags & ATA_DFLAG_LBA) {
1207 		tf->flags |= ATA_TFLAG_LBA;
1208 
1209 		if (lba_28_ok(block, n_block)) {
1210 			/* use LBA28 */
1211 			tf->command = ATA_CMD_VERIFY;
1212 			tf->device |= (block >> 24) & 0xf;
1213 		} else if (lba_48_ok(block, n_block)) {
1214 			if (!(dev->flags & ATA_DFLAG_LBA48))
1215 				goto out_of_range;
1216 
1217 			/* use LBA48 */
1218 			tf->flags |= ATA_TFLAG_LBA48;
1219 			tf->command = ATA_CMD_VERIFY_EXT;
1220 
1221 			tf->hob_nsect = (n_block >> 8) & 0xff;
1222 
1223 			tf->hob_lbah = (block >> 40) & 0xff;
1224 			tf->hob_lbam = (block >> 32) & 0xff;
1225 			tf->hob_lbal = (block >> 24) & 0xff;
1226 		} else
1227 			/* request too large even for LBA48 */
1228 			goto out_of_range;
1229 
1230 		tf->nsect = n_block & 0xff;
1231 
1232 		tf->lbah = (block >> 16) & 0xff;
1233 		tf->lbam = (block >> 8) & 0xff;
1234 		tf->lbal = block & 0xff;
1235 
1236 		tf->device |= ATA_LBA;
1237 	} else {
1238 		/* CHS */
1239 		u32 sect, head, cyl, track;
1240 
1241 		if (!lba_28_ok(block, n_block))
1242 			goto out_of_range;
1243 
1244 		/* Convert LBA to CHS */
1245 		track = (u32)block / dev->sectors;
1246 		cyl   = track / dev->heads;
1247 		head  = track % dev->heads;
1248 		sect  = (u32)block % dev->sectors + 1;
1249 
1250 		DPRINTK("block %u track %u cyl %u head %u sect %u\n",
1251 			(u32)block, track, cyl, head, sect);
1252 
1253 		/* Check whether the converted CHS can fit.
1254 		   Cylinder: 0-65535
1255 		   Head: 0-15
1256 		   Sector: 1-255*/
1257 		if ((cyl >> 16) || (head >> 4) || (sect >> 8) || (!sect))
1258 			goto out_of_range;
1259 
1260 		tf->command = ATA_CMD_VERIFY;
1261 		tf->nsect = n_block & 0xff; /* Sector count 0 means 256 sectors */
1262 		tf->lbal = sect;
1263 		tf->lbam = cyl;
1264 		tf->lbah = cyl >> 8;
1265 		tf->device |= head;
1266 	}
1267 
1268 	return 0;
1269 
1270 invalid_fld:
1271 	ata_scsi_set_sense(scmd, ILLEGAL_REQUEST, 0x24, 0x0);
1272 	/* "Invalid field in cbd" */
1273 	return 1;
1274 
1275 out_of_range:
1276 	ata_scsi_set_sense(scmd, ILLEGAL_REQUEST, 0x21, 0x0);
1277 	/* "Logical Block Address out of range" */
1278 	return 1;
1279 
1280 nothing_to_do:
1281 	scmd->result = SAM_STAT_GOOD;
1282 	return 1;
1283 }
1284 
1285 /**
1286  *	ata_scsi_rw_xlat - Translate SCSI r/w command into an ATA one
1287  *	@qc: Storage for translated ATA taskfile
1288  *
1289  *	Converts any of six SCSI read/write commands into the
1290  *	ATA counterpart, including starting sector (LBA),
1291  *	sector count, and taking into account the device's LBA48
1292  *	support.
1293  *
1294  *	Commands %READ_6, %READ_10, %READ_16, %WRITE_6, %WRITE_10, and
1295  *	%WRITE_16 are currently supported.
1296  *
1297  *	LOCKING:
1298  *	spin_lock_irqsave(host lock)
1299  *
1300  *	RETURNS:
1301  *	Zero on success, non-zero on error.
1302  */
1303 static unsigned int ata_scsi_rw_xlat(struct ata_queued_cmd *qc)
1304 {
1305 	struct scsi_cmnd *scmd = qc->scsicmd;
1306 	const u8 *cdb = scmd->cmnd;
1307 	unsigned int tf_flags = 0;
1308 	u64 block;
1309 	u32 n_block;
1310 	int rc;
1311 
1312 	if (cdb[0] == WRITE_10 || cdb[0] == WRITE_6 || cdb[0] == WRITE_16)
1313 		tf_flags |= ATA_TFLAG_WRITE;
1314 
1315 	/* Calculate the SCSI LBA, transfer length and FUA. */
1316 	switch (cdb[0]) {
1317 	case READ_10:
1318 	case WRITE_10:
1319 		if (unlikely(scmd->cmd_len < 10))
1320 			goto invalid_fld;
1321 		scsi_10_lba_len(cdb, &block, &n_block);
1322 		if (unlikely(cdb[1] & (1 << 3)))
1323 			tf_flags |= ATA_TFLAG_FUA;
1324 		break;
1325 	case READ_6:
1326 	case WRITE_6:
1327 		if (unlikely(scmd->cmd_len < 6))
1328 			goto invalid_fld;
1329 		scsi_6_lba_len(cdb, &block, &n_block);
1330 
1331 		/* for 6-byte r/w commands, transfer length 0
1332 		 * means 256 blocks of data, not 0 block.
1333 		 */
1334 		if (!n_block)
1335 			n_block = 256;
1336 		break;
1337 	case READ_16:
1338 	case WRITE_16:
1339 		if (unlikely(scmd->cmd_len < 16))
1340 			goto invalid_fld;
1341 		scsi_16_lba_len(cdb, &block, &n_block);
1342 		if (unlikely(cdb[1] & (1 << 3)))
1343 			tf_flags |= ATA_TFLAG_FUA;
1344 		break;
1345 	default:
1346 		DPRINTK("no-byte command\n");
1347 		goto invalid_fld;
1348 	}
1349 
1350 	/* Check and compose ATA command */
1351 	if (!n_block)
1352 		/* For 10-byte and 16-byte SCSI R/W commands, transfer
1353 		 * length 0 means transfer 0 block of data.
1354 		 * However, for ATA R/W commands, sector count 0 means
1355 		 * 256 or 65536 sectors, not 0 sectors as in SCSI.
1356 		 *
1357 		 * WARNING: one or two older ATA drives treat 0 as 0...
1358 		 */
1359 		goto nothing_to_do;
1360 
1361 	qc->flags |= ATA_QCFLAG_IO;
1362 	qc->nsect = n_block;
1363 
1364 	rc = ata_build_rw_tf(&qc->tf, qc->dev, block, n_block, tf_flags,
1365 			     qc->tag);
1366 	if (likely(rc == 0))
1367 		return 0;
1368 
1369 	if (rc == -ERANGE)
1370 		goto out_of_range;
1371 	/* treat all other errors as -EINVAL, fall through */
1372 invalid_fld:
1373 	ata_scsi_set_sense(scmd, ILLEGAL_REQUEST, 0x24, 0x0);
1374 	/* "Invalid field in cbd" */
1375 	return 1;
1376 
1377 out_of_range:
1378 	ata_scsi_set_sense(scmd, ILLEGAL_REQUEST, 0x21, 0x0);
1379 	/* "Logical Block Address out of range" */
1380 	return 1;
1381 
1382 nothing_to_do:
1383 	scmd->result = SAM_STAT_GOOD;
1384 	return 1;
1385 }
1386 
1387 static void ata_scsi_qc_complete(struct ata_queued_cmd *qc)
1388 {
1389 	struct ata_port *ap = qc->ap;
1390 	struct scsi_cmnd *cmd = qc->scsicmd;
1391 	u8 *cdb = cmd->cmnd;
1392  	int need_sense = (qc->err_mask != 0);
1393 
1394 	/* We snoop the SET_FEATURES - Write Cache ON/OFF command, and
1395 	 * schedule EH_REVALIDATE operation to update the IDENTIFY DEVICE
1396 	 * cache
1397 	 */
1398 	if (ap->ops->error_handler &&
1399 	    !need_sense && (qc->tf.command == ATA_CMD_SET_FEATURES) &&
1400 	    ((qc->tf.feature == SETFEATURES_WC_ON) ||
1401 	     (qc->tf.feature == SETFEATURES_WC_OFF))) {
1402 		ap->eh_info.action |= ATA_EH_REVALIDATE;
1403 		ata_port_schedule_eh(ap);
1404 	}
1405 
1406 	/* For ATA pass thru (SAT) commands, generate a sense block if
1407 	 * user mandated it or if there's an error.  Note that if we
1408 	 * generate because the user forced us to, a check condition
1409 	 * is generated and the ATA register values are returned
1410 	 * whether the command completed successfully or not. If there
1411 	 * was no error, SK, ASC and ASCQ will all be zero.
1412 	 */
1413 	if (((cdb[0] == ATA_16) || (cdb[0] == ATA_12)) &&
1414  	    ((cdb[2] & 0x20) || need_sense)) {
1415 		ata_gen_passthru_sense(qc);
1416 	} else {
1417 		if (!need_sense) {
1418 			cmd->result = SAM_STAT_GOOD;
1419 		} else {
1420 			/* TODO: decide which descriptor format to use
1421 			 * for 48b LBA devices and call that here
1422 			 * instead of the fixed desc, which is only
1423 			 * good for smaller LBA (and maybe CHS?)
1424 			 * devices.
1425 			 */
1426 			ata_gen_ata_sense(qc);
1427 		}
1428 	}
1429 
1430 	if (need_sense && !ap->ops->error_handler)
1431 		ata_dump_status(ap->id, &qc->result_tf);
1432 
1433 	qc->scsidone(cmd);
1434 
1435 	ata_qc_free(qc);
1436 }
1437 
1438 /**
1439  *	ata_scmd_need_defer - Check whether we need to defer scmd
1440  *	@dev: ATA device to which the command is addressed
1441  *	@is_io: Is the command IO (and thus possibly NCQ)?
1442  *
1443  *	NCQ and non-NCQ commands cannot run together.  As upper layer
1444  *	only knows the queue depth, we are responsible for maintaining
1445  *	exclusion.  This function checks whether a new command can be
1446  *	issued to @dev.
1447  *
1448  *	LOCKING:
1449  *	spin_lock_irqsave(host lock)
1450  *
1451  *	RETURNS:
1452  *	1 if deferring is needed, 0 otherwise.
1453  */
1454 static int ata_scmd_need_defer(struct ata_device *dev, int is_io)
1455 {
1456 	struct ata_port *ap = dev->ap;
1457 
1458 	if (!(dev->flags & ATA_DFLAG_NCQ))
1459 		return 0;
1460 
1461 	if (is_io) {
1462 		if (!ata_tag_valid(ap->active_tag))
1463 			return 0;
1464 	} else {
1465 		if (!ata_tag_valid(ap->active_tag) && !ap->sactive)
1466 			return 0;
1467 	}
1468 	return 1;
1469 }
1470 
1471 /**
1472  *	ata_scsi_translate - Translate then issue SCSI command to ATA device
1473  *	@dev: ATA device to which the command is addressed
1474  *	@cmd: SCSI command to execute
1475  *	@done: SCSI command completion function
1476  *	@xlat_func: Actor which translates @cmd to an ATA taskfile
1477  *
1478  *	Our ->queuecommand() function has decided that the SCSI
1479  *	command issued can be directly translated into an ATA
1480  *	command, rather than handled internally.
1481  *
1482  *	This function sets up an ata_queued_cmd structure for the
1483  *	SCSI command, and sends that ata_queued_cmd to the hardware.
1484  *
1485  *	The xlat_func argument (actor) returns 0 if ready to execute
1486  *	ATA command, else 1 to finish translation. If 1 is returned
1487  *	then cmd->result (and possibly cmd->sense_buffer) are assumed
1488  *	to be set reflecting an error condition or clean (early)
1489  *	termination.
1490  *
1491  *	LOCKING:
1492  *	spin_lock_irqsave(host lock)
1493  *
1494  *	RETURNS:
1495  *	0 on success, SCSI_ML_QUEUE_DEVICE_BUSY if the command
1496  *	needs to be deferred.
1497  */
1498 static int ata_scsi_translate(struct ata_device *dev, struct scsi_cmnd *cmd,
1499 			      void (*done)(struct scsi_cmnd *),
1500 			      ata_xlat_func_t xlat_func)
1501 {
1502 	struct ata_queued_cmd *qc;
1503 	int is_io = xlat_func == ata_scsi_rw_xlat;
1504 
1505 	VPRINTK("ENTER\n");
1506 
1507 	if (unlikely(ata_scmd_need_defer(dev, is_io)))
1508 		goto defer;
1509 
1510 	qc = ata_scsi_qc_new(dev, cmd, done);
1511 	if (!qc)
1512 		goto err_mem;
1513 
1514 	/* data is present; dma-map it */
1515 	if (cmd->sc_data_direction == DMA_FROM_DEVICE ||
1516 	    cmd->sc_data_direction == DMA_TO_DEVICE) {
1517 		if (unlikely(cmd->request_bufflen < 1)) {
1518 			ata_dev_printk(dev, KERN_WARNING,
1519 				       "WARNING: zero len r/w req\n");
1520 			goto err_did;
1521 		}
1522 
1523 		if (cmd->use_sg)
1524 			ata_sg_init(qc, cmd->request_buffer, cmd->use_sg);
1525 		else
1526 			ata_sg_init_one(qc, cmd->request_buffer,
1527 					cmd->request_bufflen);
1528 
1529 		qc->dma_dir = cmd->sc_data_direction;
1530 	}
1531 
1532 	qc->complete_fn = ata_scsi_qc_complete;
1533 
1534 	if (xlat_func(qc))
1535 		goto early_finish;
1536 
1537 	/* select device, send command to hardware */
1538 	ata_qc_issue(qc);
1539 
1540 	VPRINTK("EXIT\n");
1541 	return 0;
1542 
1543 early_finish:
1544         ata_qc_free(qc);
1545 	done(cmd);
1546 	DPRINTK("EXIT - early finish (good or error)\n");
1547 	return 0;
1548 
1549 err_did:
1550 	ata_qc_free(qc);
1551 	cmd->result = (DID_ERROR << 16);
1552 	done(cmd);
1553 err_mem:
1554 	DPRINTK("EXIT - internal\n");
1555 	return 0;
1556 
1557 defer:
1558 	DPRINTK("EXIT - defer\n");
1559 	return SCSI_MLQUEUE_DEVICE_BUSY;
1560 }
1561 
1562 /**
1563  *	ata_scsi_rbuf_get - Map response buffer.
1564  *	@cmd: SCSI command containing buffer to be mapped.
1565  *	@buf_out: Pointer to mapped area.
1566  *
1567  *	Maps buffer contained within SCSI command @cmd.
1568  *
1569  *	LOCKING:
1570  *	spin_lock_irqsave(host lock)
1571  *
1572  *	RETURNS:
1573  *	Length of response buffer.
1574  */
1575 
1576 static unsigned int ata_scsi_rbuf_get(struct scsi_cmnd *cmd, u8 **buf_out)
1577 {
1578 	u8 *buf;
1579 	unsigned int buflen;
1580 
1581 	if (cmd->use_sg) {
1582 		struct scatterlist *sg;
1583 
1584 		sg = (struct scatterlist *) cmd->request_buffer;
1585 		buf = kmap_atomic(sg->page, KM_IRQ0) + sg->offset;
1586 		buflen = sg->length;
1587 	} else {
1588 		buf = cmd->request_buffer;
1589 		buflen = cmd->request_bufflen;
1590 	}
1591 
1592 	*buf_out = buf;
1593 	return buflen;
1594 }
1595 
1596 /**
1597  *	ata_scsi_rbuf_put - Unmap response buffer.
1598  *	@cmd: SCSI command containing buffer to be unmapped.
1599  *	@buf: buffer to unmap
1600  *
1601  *	Unmaps response buffer contained within @cmd.
1602  *
1603  *	LOCKING:
1604  *	spin_lock_irqsave(host lock)
1605  */
1606 
1607 static inline void ata_scsi_rbuf_put(struct scsi_cmnd *cmd, u8 *buf)
1608 {
1609 	if (cmd->use_sg) {
1610 		struct scatterlist *sg;
1611 
1612 		sg = (struct scatterlist *) cmd->request_buffer;
1613 		kunmap_atomic(buf - sg->offset, KM_IRQ0);
1614 	}
1615 }
1616 
1617 /**
1618  *	ata_scsi_rbuf_fill - wrapper for SCSI command simulators
1619  *	@args: device IDENTIFY data / SCSI command of interest.
1620  *	@actor: Callback hook for desired SCSI command simulator
1621  *
1622  *	Takes care of the hard work of simulating a SCSI command...
1623  *	Mapping the response buffer, calling the command's handler,
1624  *	and handling the handler's return value.  This return value
1625  *	indicates whether the handler wishes the SCSI command to be
1626  *	completed successfully (0), or not (in which case cmd->result
1627  *	and sense buffer are assumed to be set).
1628  *
1629  *	LOCKING:
1630  *	spin_lock_irqsave(host lock)
1631  */
1632 
1633 void ata_scsi_rbuf_fill(struct ata_scsi_args *args,
1634 		        unsigned int (*actor) (struct ata_scsi_args *args,
1635 			     		   u8 *rbuf, unsigned int buflen))
1636 {
1637 	u8 *rbuf;
1638 	unsigned int buflen, rc;
1639 	struct scsi_cmnd *cmd = args->cmd;
1640 
1641 	buflen = ata_scsi_rbuf_get(cmd, &rbuf);
1642 	memset(rbuf, 0, buflen);
1643 	rc = actor(args, rbuf, buflen);
1644 	ata_scsi_rbuf_put(cmd, rbuf);
1645 
1646 	if (rc == 0)
1647 		cmd->result = SAM_STAT_GOOD;
1648 	args->done(cmd);
1649 }
1650 
1651 /**
1652  *	ATA_SCSI_RBUF_SET - helper to set values in SCSI response buffer
1653  *	@idx: byte index into SCSI response buffer
1654  *	@val: value to set
1655  *
1656  *	To be used by SCSI command simulator functions.  This macros
1657  *	expects two local variables, u8 *rbuf and unsigned int buflen,
1658  *	are in scope.
1659  *
1660  *	LOCKING:
1661  *	None.
1662  */
1663 #define ATA_SCSI_RBUF_SET(idx, val) do { \
1664 		if ((idx) < buflen) rbuf[(idx)] = (u8)(val); \
1665 	} while (0)
1666 
1667 /**
1668  *	ata_scsiop_inq_std - Simulate INQUIRY command
1669  *	@args: device IDENTIFY data / SCSI command of interest.
1670  *	@rbuf: Response buffer, to which simulated SCSI cmd output is sent.
1671  *	@buflen: Response buffer length.
1672  *
1673  *	Returns standard device identification data associated
1674  *	with non-VPD INQUIRY command output.
1675  *
1676  *	LOCKING:
1677  *	spin_lock_irqsave(host lock)
1678  */
1679 
1680 unsigned int ata_scsiop_inq_std(struct ata_scsi_args *args, u8 *rbuf,
1681 			       unsigned int buflen)
1682 {
1683 	u8 hdr[] = {
1684 		TYPE_DISK,
1685 		0,
1686 		0x5,	/* claim SPC-3 version compatibility */
1687 		2,
1688 		95 - 4
1689 	};
1690 
1691 	/* set scsi removeable (RMB) bit per ata bit */
1692 	if (ata_id_removeable(args->id))
1693 		hdr[1] |= (1 << 7);
1694 
1695 	VPRINTK("ENTER\n");
1696 
1697 	memcpy(rbuf, hdr, sizeof(hdr));
1698 
1699 	if (buflen > 35) {
1700 		memcpy(&rbuf[8], "ATA     ", 8);
1701 		ata_id_string(args->id, &rbuf[16], ATA_ID_PROD_OFS, 16);
1702 		ata_id_string(args->id, &rbuf[32], ATA_ID_FW_REV_OFS, 4);
1703 		if (rbuf[32] == 0 || rbuf[32] == ' ')
1704 			memcpy(&rbuf[32], "n/a ", 4);
1705 	}
1706 
1707 	if (buflen > 63) {
1708 		const u8 versions[] = {
1709 			0x60,	/* SAM-3 (no version claimed) */
1710 
1711 			0x03,
1712 			0x20,	/* SBC-2 (no version claimed) */
1713 
1714 			0x02,
1715 			0x60	/* SPC-3 (no version claimed) */
1716 		};
1717 
1718 		memcpy(rbuf + 59, versions, sizeof(versions));
1719 	}
1720 
1721 	return 0;
1722 }
1723 
1724 /**
1725  *	ata_scsiop_inq_00 - Simulate INQUIRY VPD page 0, list of pages
1726  *	@args: device IDENTIFY data / SCSI command of interest.
1727  *	@rbuf: Response buffer, to which simulated SCSI cmd output is sent.
1728  *	@buflen: Response buffer length.
1729  *
1730  *	Returns list of inquiry VPD pages available.
1731  *
1732  *	LOCKING:
1733  *	spin_lock_irqsave(host lock)
1734  */
1735 
1736 unsigned int ata_scsiop_inq_00(struct ata_scsi_args *args, u8 *rbuf,
1737 			      unsigned int buflen)
1738 {
1739 	const u8 pages[] = {
1740 		0x00,	/* page 0x00, this page */
1741 		0x80,	/* page 0x80, unit serial no page */
1742 		0x83	/* page 0x83, device ident page */
1743 	};
1744 	rbuf[3] = sizeof(pages);	/* number of supported VPD pages */
1745 
1746 	if (buflen > 6)
1747 		memcpy(rbuf + 4, pages, sizeof(pages));
1748 
1749 	return 0;
1750 }
1751 
1752 /**
1753  *	ata_scsiop_inq_80 - Simulate INQUIRY VPD page 80, device serial number
1754  *	@args: device IDENTIFY data / SCSI command of interest.
1755  *	@rbuf: Response buffer, to which simulated SCSI cmd output is sent.
1756  *	@buflen: Response buffer length.
1757  *
1758  *	Returns ATA device serial number.
1759  *
1760  *	LOCKING:
1761  *	spin_lock_irqsave(host lock)
1762  */
1763 
1764 unsigned int ata_scsiop_inq_80(struct ata_scsi_args *args, u8 *rbuf,
1765 			      unsigned int buflen)
1766 {
1767 	const u8 hdr[] = {
1768 		0,
1769 		0x80,			/* this page code */
1770 		0,
1771 		ATA_SERNO_LEN,		/* page len */
1772 	};
1773 	memcpy(rbuf, hdr, sizeof(hdr));
1774 
1775 	if (buflen > (ATA_SERNO_LEN + 4 - 1))
1776 		ata_id_string(args->id, (unsigned char *) &rbuf[4],
1777 			      ATA_ID_SERNO_OFS, ATA_SERNO_LEN);
1778 
1779 	return 0;
1780 }
1781 
1782 /**
1783  *	ata_scsiop_inq_83 - Simulate INQUIRY VPD page 83, device identity
1784  *	@args: device IDENTIFY data / SCSI command of interest.
1785  *	@rbuf: Response buffer, to which simulated SCSI cmd output is sent.
1786  *	@buflen: Response buffer length.
1787  *
1788  *	Yields two logical unit device identification designators:
1789  *	 - vendor specific ASCII containing the ATA serial number
1790  *	 - SAT defined "t10 vendor id based" containing ASCII vendor
1791  *	   name ("ATA     "), model and serial numbers.
1792  *
1793  *	LOCKING:
1794  *	spin_lock_irqsave(host lock)
1795  */
1796 
1797 unsigned int ata_scsiop_inq_83(struct ata_scsi_args *args, u8 *rbuf,
1798 			      unsigned int buflen)
1799 {
1800 	int num;
1801 	const int sat_model_serial_desc_len = 68;
1802 	const int ata_model_byte_len = 40;
1803 
1804 	rbuf[1] = 0x83;			/* this page code */
1805 	num = 4;
1806 
1807 	if (buflen > (ATA_SERNO_LEN + num + 3)) {
1808 		/* piv=0, assoc=lu, code_set=ACSII, designator=vendor */
1809 		rbuf[num + 0] = 2;
1810 		rbuf[num + 3] = ATA_SERNO_LEN;
1811 		num += 4;
1812 		ata_id_string(args->id, (unsigned char *) rbuf + num,
1813 			      ATA_ID_SERNO_OFS, ATA_SERNO_LEN);
1814 		num += ATA_SERNO_LEN;
1815 	}
1816 	if (buflen > (sat_model_serial_desc_len + num + 3)) {
1817 		/* SAT defined lu model and serial numbers descriptor */
1818 		/* piv=0, assoc=lu, code_set=ACSII, designator=t10 vendor id */
1819 		rbuf[num + 0] = 2;
1820 		rbuf[num + 1] = 1;
1821 		rbuf[num + 3] = sat_model_serial_desc_len;
1822 		num += 4;
1823 		memcpy(rbuf + num, "ATA     ", 8);
1824 		num += 8;
1825 		ata_id_string(args->id, (unsigned char *) rbuf + num,
1826 			      ATA_ID_PROD_OFS, ata_model_byte_len);
1827 		num += ata_model_byte_len;
1828 		ata_id_string(args->id, (unsigned char *) rbuf + num,
1829 			      ATA_ID_SERNO_OFS, ATA_SERNO_LEN);
1830 		num += ATA_SERNO_LEN;
1831 	}
1832 	rbuf[3] = num - 4;    /* page len (assume less than 256 bytes) */
1833 	return 0;
1834 }
1835 
1836 /**
1837  *	ata_scsiop_noop - Command handler that simply returns success.
1838  *	@args: device IDENTIFY data / SCSI command of interest.
1839  *	@rbuf: Response buffer, to which simulated SCSI cmd output is sent.
1840  *	@buflen: Response buffer length.
1841  *
1842  *	No operation.  Simply returns success to caller, to indicate
1843  *	that the caller should successfully complete this SCSI command.
1844  *
1845  *	LOCKING:
1846  *	spin_lock_irqsave(host lock)
1847  */
1848 
1849 unsigned int ata_scsiop_noop(struct ata_scsi_args *args, u8 *rbuf,
1850 			    unsigned int buflen)
1851 {
1852 	VPRINTK("ENTER\n");
1853 	return 0;
1854 }
1855 
1856 /**
1857  *	ata_msense_push - Push data onto MODE SENSE data output buffer
1858  *	@ptr_io: (input/output) Location to store more output data
1859  *	@last: End of output data buffer
1860  *	@buf: Pointer to BLOB being added to output buffer
1861  *	@buflen: Length of BLOB
1862  *
1863  *	Store MODE SENSE data on an output buffer.
1864  *
1865  *	LOCKING:
1866  *	None.
1867  */
1868 
1869 static void ata_msense_push(u8 **ptr_io, const u8 *last,
1870 			    const u8 *buf, unsigned int buflen)
1871 {
1872 	u8 *ptr = *ptr_io;
1873 
1874 	if ((ptr + buflen - 1) > last)
1875 		return;
1876 
1877 	memcpy(ptr, buf, buflen);
1878 
1879 	ptr += buflen;
1880 
1881 	*ptr_io = ptr;
1882 }
1883 
1884 /**
1885  *	ata_msense_caching - Simulate MODE SENSE caching info page
1886  *	@id: device IDENTIFY data
1887  *	@ptr_io: (input/output) Location to store more output data
1888  *	@last: End of output data buffer
1889  *
1890  *	Generate a caching info page, which conditionally indicates
1891  *	write caching to the SCSI layer, depending on device
1892  *	capabilities.
1893  *
1894  *	LOCKING:
1895  *	None.
1896  */
1897 
1898 static unsigned int ata_msense_caching(u16 *id, u8 **ptr_io,
1899 				       const u8 *last)
1900 {
1901 	u8 page[CACHE_MPAGE_LEN];
1902 
1903 	memcpy(page, def_cache_mpage, sizeof(page));
1904 	if (ata_id_wcache_enabled(id))
1905 		page[2] |= (1 << 2);	/* write cache enable */
1906 	if (!ata_id_rahead_enabled(id))
1907 		page[12] |= (1 << 5);	/* disable read ahead */
1908 
1909 	ata_msense_push(ptr_io, last, page, sizeof(page));
1910 	return sizeof(page);
1911 }
1912 
1913 /**
1914  *	ata_msense_ctl_mode - Simulate MODE SENSE control mode page
1915  *	@dev: Device associated with this MODE SENSE command
1916  *	@ptr_io: (input/output) Location to store more output data
1917  *	@last: End of output data buffer
1918  *
1919  *	Generate a generic MODE SENSE control mode page.
1920  *
1921  *	LOCKING:
1922  *	None.
1923  */
1924 
1925 static unsigned int ata_msense_ctl_mode(u8 **ptr_io, const u8 *last)
1926 {
1927 	ata_msense_push(ptr_io, last, def_control_mpage,
1928 			sizeof(def_control_mpage));
1929 	return sizeof(def_control_mpage);
1930 }
1931 
1932 /**
1933  *	ata_msense_rw_recovery - Simulate MODE SENSE r/w error recovery page
1934  *	@dev: Device associated with this MODE SENSE command
1935  *	@ptr_io: (input/output) Location to store more output data
1936  *	@last: End of output data buffer
1937  *
1938  *	Generate a generic MODE SENSE r/w error recovery page.
1939  *
1940  *	LOCKING:
1941  *	None.
1942  */
1943 
1944 static unsigned int ata_msense_rw_recovery(u8 **ptr_io, const u8 *last)
1945 {
1946 
1947 	ata_msense_push(ptr_io, last, def_rw_recovery_mpage,
1948 			sizeof(def_rw_recovery_mpage));
1949 	return sizeof(def_rw_recovery_mpage);
1950 }
1951 
1952 /*
1953  * We can turn this into a real blacklist if it's needed, for now just
1954  * blacklist any Maxtor BANC1G10 revision firmware
1955  */
1956 static int ata_dev_supports_fua(u16 *id)
1957 {
1958 	unsigned char model[41], fw[9];
1959 
1960 	if (!libata_fua)
1961 		return 0;
1962 	if (!ata_id_has_fua(id))
1963 		return 0;
1964 
1965 	ata_id_c_string(id, model, ATA_ID_PROD_OFS, sizeof(model));
1966 	ata_id_c_string(id, fw, ATA_ID_FW_REV_OFS, sizeof(fw));
1967 
1968 	if (strcmp(model, "Maxtor"))
1969 		return 1;
1970 	if (strcmp(fw, "BANC1G10"))
1971 		return 1;
1972 
1973 	return 0; /* blacklisted */
1974 }
1975 
1976 /**
1977  *	ata_scsiop_mode_sense - Simulate MODE SENSE 6, 10 commands
1978  *	@args: device IDENTIFY data / SCSI command of interest.
1979  *	@rbuf: Response buffer, to which simulated SCSI cmd output is sent.
1980  *	@buflen: Response buffer length.
1981  *
1982  *	Simulate MODE SENSE commands. Assume this is invoked for direct
1983  *	access devices (e.g. disks) only. There should be no block
1984  *	descriptor for other device types.
1985  *
1986  *	LOCKING:
1987  *	spin_lock_irqsave(host lock)
1988  */
1989 
1990 unsigned int ata_scsiop_mode_sense(struct ata_scsi_args *args, u8 *rbuf,
1991 				  unsigned int buflen)
1992 {
1993 	struct ata_device *dev = args->dev;
1994 	u8 *scsicmd = args->cmd->cmnd, *p, *last;
1995 	const u8 sat_blk_desc[] = {
1996 		0, 0, 0, 0,	/* number of blocks: sat unspecified */
1997 		0,
1998 		0, 0x2, 0x0	/* block length: 512 bytes */
1999 	};
2000 	u8 pg, spg;
2001 	unsigned int ebd, page_control, six_byte, output_len, alloc_len, minlen;
2002 	u8 dpofua;
2003 
2004 	VPRINTK("ENTER\n");
2005 
2006 	six_byte = (scsicmd[0] == MODE_SENSE);
2007 	ebd = !(scsicmd[1] & 0x8);      /* dbd bit inverted == edb */
2008 	/*
2009 	 * LLBA bit in msense(10) ignored (compliant)
2010 	 */
2011 
2012 	page_control = scsicmd[2] >> 6;
2013 	switch (page_control) {
2014 	case 0: /* current */
2015 		break;  /* supported */
2016 	case 3: /* saved */
2017 		goto saving_not_supp;
2018 	case 1: /* changeable */
2019 	case 2: /* defaults */
2020 	default:
2021 		goto invalid_fld;
2022 	}
2023 
2024 	if (six_byte) {
2025 		output_len = 4 + (ebd ? 8 : 0);
2026 		alloc_len = scsicmd[4];
2027 	} else {
2028 		output_len = 8 + (ebd ? 8 : 0);
2029 		alloc_len = (scsicmd[7] << 8) + scsicmd[8];
2030 	}
2031 	minlen = (alloc_len < buflen) ? alloc_len : buflen;
2032 
2033 	p = rbuf + output_len;
2034 	last = rbuf + minlen - 1;
2035 
2036 	pg = scsicmd[2] & 0x3f;
2037 	spg = scsicmd[3];
2038 	/*
2039 	 * No mode subpages supported (yet) but asking for _all_
2040 	 * subpages may be valid
2041 	 */
2042 	if (spg && (spg != ALL_SUB_MPAGES))
2043 		goto invalid_fld;
2044 
2045 	switch(pg) {
2046 	case RW_RECOVERY_MPAGE:
2047 		output_len += ata_msense_rw_recovery(&p, last);
2048 		break;
2049 
2050 	case CACHE_MPAGE:
2051 		output_len += ata_msense_caching(args->id, &p, last);
2052 		break;
2053 
2054 	case CONTROL_MPAGE: {
2055 		output_len += ata_msense_ctl_mode(&p, last);
2056 		break;
2057 		}
2058 
2059 	case ALL_MPAGES:
2060 		output_len += ata_msense_rw_recovery(&p, last);
2061 		output_len += ata_msense_caching(args->id, &p, last);
2062 		output_len += ata_msense_ctl_mode(&p, last);
2063 		break;
2064 
2065 	default:		/* invalid page code */
2066 		goto invalid_fld;
2067 	}
2068 
2069 	if (minlen < 1)
2070 		return 0;
2071 
2072 	dpofua = 0;
2073 	if (ata_dev_supports_fua(args->id) && (dev->flags & ATA_DFLAG_LBA48) &&
2074 	    (!(dev->flags & ATA_DFLAG_PIO) || dev->multi_count))
2075 		dpofua = 1 << 4;
2076 
2077 	if (six_byte) {
2078 		output_len--;
2079 		rbuf[0] = output_len;
2080 		if (minlen > 2)
2081 			rbuf[2] |= dpofua;
2082 		if (ebd) {
2083 			if (minlen > 3)
2084 				rbuf[3] = sizeof(sat_blk_desc);
2085 			if (minlen > 11)
2086 				memcpy(rbuf + 4, sat_blk_desc,
2087 				       sizeof(sat_blk_desc));
2088 		}
2089 	} else {
2090 		output_len -= 2;
2091 		rbuf[0] = output_len >> 8;
2092 		if (minlen > 1)
2093 			rbuf[1] = output_len;
2094 		if (minlen > 3)
2095 			rbuf[3] |= dpofua;
2096 		if (ebd) {
2097 			if (minlen > 7)
2098 				rbuf[7] = sizeof(sat_blk_desc);
2099 			if (minlen > 15)
2100 				memcpy(rbuf + 8, sat_blk_desc,
2101 				       sizeof(sat_blk_desc));
2102 		}
2103 	}
2104 	return 0;
2105 
2106 invalid_fld:
2107 	ata_scsi_set_sense(args->cmd, ILLEGAL_REQUEST, 0x24, 0x0);
2108 	/* "Invalid field in cbd" */
2109 	return 1;
2110 
2111 saving_not_supp:
2112 	ata_scsi_set_sense(args->cmd, ILLEGAL_REQUEST, 0x39, 0x0);
2113 	 /* "Saving parameters not supported" */
2114 	return 1;
2115 }
2116 
2117 /**
2118  *	ata_scsiop_read_cap - Simulate READ CAPACITY[ 16] commands
2119  *	@args: device IDENTIFY data / SCSI command of interest.
2120  *	@rbuf: Response buffer, to which simulated SCSI cmd output is sent.
2121  *	@buflen: Response buffer length.
2122  *
2123  *	Simulate READ CAPACITY commands.
2124  *
2125  *	LOCKING:
2126  *	None.
2127  */
2128 unsigned int ata_scsiop_read_cap(struct ata_scsi_args *args, u8 *rbuf,
2129 			        unsigned int buflen)
2130 {
2131 	u64 last_lba = args->dev->n_sectors - 1; /* LBA of the last block */
2132 
2133 	VPRINTK("ENTER\n");
2134 
2135 	if (args->cmd->cmnd[0] == READ_CAPACITY) {
2136 		if (last_lba >= 0xffffffffULL)
2137 			last_lba = 0xffffffff;
2138 
2139 		/* sector count, 32-bit */
2140 		ATA_SCSI_RBUF_SET(0, last_lba >> (8 * 3));
2141 		ATA_SCSI_RBUF_SET(1, last_lba >> (8 * 2));
2142 		ATA_SCSI_RBUF_SET(2, last_lba >> (8 * 1));
2143 		ATA_SCSI_RBUF_SET(3, last_lba);
2144 
2145 		/* sector size */
2146 		ATA_SCSI_RBUF_SET(6, ATA_SECT_SIZE >> 8);
2147 		ATA_SCSI_RBUF_SET(7, ATA_SECT_SIZE);
2148 	} else {
2149 		/* sector count, 64-bit */
2150 		ATA_SCSI_RBUF_SET(0, last_lba >> (8 * 7));
2151 		ATA_SCSI_RBUF_SET(1, last_lba >> (8 * 6));
2152 		ATA_SCSI_RBUF_SET(2, last_lba >> (8 * 5));
2153 		ATA_SCSI_RBUF_SET(3, last_lba >> (8 * 4));
2154 		ATA_SCSI_RBUF_SET(4, last_lba >> (8 * 3));
2155 		ATA_SCSI_RBUF_SET(5, last_lba >> (8 * 2));
2156 		ATA_SCSI_RBUF_SET(6, last_lba >> (8 * 1));
2157 		ATA_SCSI_RBUF_SET(7, last_lba);
2158 
2159 		/* sector size */
2160 		ATA_SCSI_RBUF_SET(10, ATA_SECT_SIZE >> 8);
2161 		ATA_SCSI_RBUF_SET(11, ATA_SECT_SIZE);
2162 	}
2163 
2164 	return 0;
2165 }
2166 
2167 /**
2168  *	ata_scsiop_report_luns - Simulate REPORT LUNS command
2169  *	@args: device IDENTIFY data / SCSI command of interest.
2170  *	@rbuf: Response buffer, to which simulated SCSI cmd output is sent.
2171  *	@buflen: Response buffer length.
2172  *
2173  *	Simulate REPORT LUNS command.
2174  *
2175  *	LOCKING:
2176  *	spin_lock_irqsave(host lock)
2177  */
2178 
2179 unsigned int ata_scsiop_report_luns(struct ata_scsi_args *args, u8 *rbuf,
2180 				   unsigned int buflen)
2181 {
2182 	VPRINTK("ENTER\n");
2183 	rbuf[3] = 8;	/* just one lun, LUN 0, size 8 bytes */
2184 
2185 	return 0;
2186 }
2187 
2188 /**
2189  *	ata_scsi_set_sense - Set SCSI sense data and status
2190  *	@cmd: SCSI request to be handled
2191  *	@sk: SCSI-defined sense key
2192  *	@asc: SCSI-defined additional sense code
2193  *	@ascq: SCSI-defined additional sense code qualifier
2194  *
2195  *	Helper function that builds a valid fixed format, current
2196  *	response code and the given sense key (sk), additional sense
2197  *	code (asc) and additional sense code qualifier (ascq) with
2198  *	a SCSI command status of %SAM_STAT_CHECK_CONDITION and
2199  *	DRIVER_SENSE set in the upper bits of scsi_cmnd::result .
2200  *
2201  *	LOCKING:
2202  *	Not required
2203  */
2204 
2205 void ata_scsi_set_sense(struct scsi_cmnd *cmd, u8 sk, u8 asc, u8 ascq)
2206 {
2207 	cmd->result = (DRIVER_SENSE << 24) | SAM_STAT_CHECK_CONDITION;
2208 
2209 	cmd->sense_buffer[0] = 0x70;	/* fixed format, current */
2210 	cmd->sense_buffer[2] = sk;
2211 	cmd->sense_buffer[7] = 18 - 8;	/* additional sense length */
2212 	cmd->sense_buffer[12] = asc;
2213 	cmd->sense_buffer[13] = ascq;
2214 }
2215 
2216 /**
2217  *	ata_scsi_badcmd - End a SCSI request with an error
2218  *	@cmd: SCSI request to be handled
2219  *	@done: SCSI command completion function
2220  *	@asc: SCSI-defined additional sense code
2221  *	@ascq: SCSI-defined additional sense code qualifier
2222  *
2223  *	Helper function that completes a SCSI command with
2224  *	%SAM_STAT_CHECK_CONDITION, with a sense key %ILLEGAL_REQUEST
2225  *	and the specified additional sense codes.
2226  *
2227  *	LOCKING:
2228  *	spin_lock_irqsave(host lock)
2229  */
2230 
2231 void ata_scsi_badcmd(struct scsi_cmnd *cmd, void (*done)(struct scsi_cmnd *), u8 asc, u8 ascq)
2232 {
2233 	DPRINTK("ENTER\n");
2234 	ata_scsi_set_sense(cmd, ILLEGAL_REQUEST, asc, ascq);
2235 
2236 	done(cmd);
2237 }
2238 
2239 static void atapi_sense_complete(struct ata_queued_cmd *qc)
2240 {
2241 	if (qc->err_mask && ((qc->err_mask & AC_ERR_DEV) == 0)) {
2242 		/* FIXME: not quite right; we don't want the
2243 		 * translation of taskfile registers into
2244 		 * a sense descriptors, since that's only
2245 		 * correct for ATA, not ATAPI
2246 		 */
2247 		ata_gen_passthru_sense(qc);
2248 	}
2249 
2250 	qc->scsidone(qc->scsicmd);
2251 	ata_qc_free(qc);
2252 }
2253 
2254 /* is it pointless to prefer PIO for "safety reasons"? */
2255 static inline int ata_pio_use_silly(struct ata_port *ap)
2256 {
2257 	return (ap->flags & ATA_FLAG_PIO_DMA);
2258 }
2259 
2260 static void atapi_request_sense(struct ata_queued_cmd *qc)
2261 {
2262 	struct ata_port *ap = qc->ap;
2263 	struct scsi_cmnd *cmd = qc->scsicmd;
2264 
2265 	DPRINTK("ATAPI request sense\n");
2266 
2267 	/* FIXME: is this needed? */
2268 	memset(cmd->sense_buffer, 0, sizeof(cmd->sense_buffer));
2269 
2270 	ap->ops->tf_read(ap, &qc->tf);
2271 
2272 	/* fill these in, for the case where they are -not- overwritten */
2273 	cmd->sense_buffer[0] = 0x70;
2274 	cmd->sense_buffer[2] = qc->tf.feature >> 4;
2275 
2276 	ata_qc_reinit(qc);
2277 
2278 	ata_sg_init_one(qc, cmd->sense_buffer, sizeof(cmd->sense_buffer));
2279 	qc->dma_dir = DMA_FROM_DEVICE;
2280 
2281 	memset(&qc->cdb, 0, qc->dev->cdb_len);
2282 	qc->cdb[0] = REQUEST_SENSE;
2283 	qc->cdb[4] = SCSI_SENSE_BUFFERSIZE;
2284 
2285 	qc->tf.flags |= ATA_TFLAG_ISADDR | ATA_TFLAG_DEVICE;
2286 	qc->tf.command = ATA_CMD_PACKET;
2287 
2288 	if (ata_pio_use_silly(ap)) {
2289 		qc->tf.protocol = ATA_PROT_ATAPI_DMA;
2290 		qc->tf.feature |= ATAPI_PKT_DMA;
2291 	} else {
2292 		qc->tf.protocol = ATA_PROT_ATAPI;
2293 		qc->tf.lbam = (8 * 1024) & 0xff;
2294 		qc->tf.lbah = (8 * 1024) >> 8;
2295 	}
2296 	qc->nbytes = SCSI_SENSE_BUFFERSIZE;
2297 
2298 	qc->complete_fn = atapi_sense_complete;
2299 
2300 	ata_qc_issue(qc);
2301 
2302 	DPRINTK("EXIT\n");
2303 }
2304 
2305 static void atapi_qc_complete(struct ata_queued_cmd *qc)
2306 {
2307 	struct scsi_cmnd *cmd = qc->scsicmd;
2308 	unsigned int err_mask = qc->err_mask;
2309 
2310 	VPRINTK("ENTER, err_mask 0x%X\n", err_mask);
2311 
2312 	/* handle completion from new EH */
2313 	if (unlikely(qc->ap->ops->error_handler &&
2314 		     (err_mask || qc->flags & ATA_QCFLAG_SENSE_VALID))) {
2315 
2316 		if (!(qc->flags & ATA_QCFLAG_SENSE_VALID)) {
2317 			/* FIXME: not quite right; we don't want the
2318 			 * translation of taskfile registers into a
2319 			 * sense descriptors, since that's only
2320 			 * correct for ATA, not ATAPI
2321 			 */
2322 			ata_gen_passthru_sense(qc);
2323 		}
2324 
2325 		/* SCSI EH automatically locks door if sdev->locked is
2326 		 * set.  Sometimes door lock request continues to
2327 		 * fail, for example, when no media is present.  This
2328 		 * creates a loop - SCSI EH issues door lock which
2329 		 * fails and gets invoked again to acquire sense data
2330 		 * for the failed command.
2331 		 *
2332 		 * If door lock fails, always clear sdev->locked to
2333 		 * avoid this infinite loop.
2334 		 */
2335 		if (qc->cdb[0] == ALLOW_MEDIUM_REMOVAL)
2336 			qc->dev->sdev->locked = 0;
2337 
2338 		qc->scsicmd->result = SAM_STAT_CHECK_CONDITION;
2339 		qc->scsidone(cmd);
2340 		ata_qc_free(qc);
2341 		return;
2342 	}
2343 
2344 	/* successful completion or old EH failure path */
2345 	if (unlikely(err_mask & AC_ERR_DEV)) {
2346 		cmd->result = SAM_STAT_CHECK_CONDITION;
2347 		atapi_request_sense(qc);
2348 		return;
2349 	} else if (unlikely(err_mask)) {
2350 		/* FIXME: not quite right; we don't want the
2351 		 * translation of taskfile registers into
2352 		 * a sense descriptors, since that's only
2353 		 * correct for ATA, not ATAPI
2354 		 */
2355 		ata_gen_passthru_sense(qc);
2356 	} else {
2357 		u8 *scsicmd = cmd->cmnd;
2358 
2359 		if ((scsicmd[0] == INQUIRY) && ((scsicmd[1] & 0x03) == 0)) {
2360 			u8 *buf = NULL;
2361 			unsigned int buflen;
2362 
2363 			buflen = ata_scsi_rbuf_get(cmd, &buf);
2364 
2365 	/* ATAPI devices typically report zero for their SCSI version,
2366 	 * and sometimes deviate from the spec WRT response data
2367 	 * format.  If SCSI version is reported as zero like normal,
2368 	 * then we make the following fixups:  1) Fake MMC-5 version,
2369 	 * to indicate to the Linux scsi midlayer this is a modern
2370 	 * device.  2) Ensure response data format / ATAPI information
2371 	 * are always correct.
2372 	 */
2373 			if (buf[2] == 0) {
2374 				buf[2] = 0x5;
2375 				buf[3] = 0x32;
2376 			}
2377 
2378 			ata_scsi_rbuf_put(cmd, buf);
2379 		}
2380 
2381 		cmd->result = SAM_STAT_GOOD;
2382 	}
2383 
2384 	qc->scsidone(cmd);
2385 	ata_qc_free(qc);
2386 }
2387 /**
2388  *	atapi_xlat - Initialize PACKET taskfile
2389  *	@qc: command structure to be initialized
2390  *
2391  *	LOCKING:
2392  *	spin_lock_irqsave(host lock)
2393  *
2394  *	RETURNS:
2395  *	Zero on success, non-zero on failure.
2396  */
2397 static unsigned int atapi_xlat(struct ata_queued_cmd *qc)
2398 {
2399 	struct scsi_cmnd *scmd = qc->scsicmd;
2400 	struct ata_device *dev = qc->dev;
2401 	int using_pio = (dev->flags & ATA_DFLAG_PIO);
2402 	int nodata = (scmd->sc_data_direction == DMA_NONE);
2403 
2404 	if (!using_pio)
2405 		/* Check whether ATAPI DMA is safe */
2406 		if (ata_check_atapi_dma(qc))
2407 			using_pio = 1;
2408 
2409 	memset(qc->cdb, 0, dev->cdb_len);
2410 	memcpy(qc->cdb, scmd->cmnd, scmd->cmd_len);
2411 
2412 	qc->complete_fn = atapi_qc_complete;
2413 
2414 	qc->tf.flags |= ATA_TFLAG_ISADDR | ATA_TFLAG_DEVICE;
2415 	if (scmd->sc_data_direction == DMA_TO_DEVICE) {
2416 		qc->tf.flags |= ATA_TFLAG_WRITE;
2417 		DPRINTK("direction: write\n");
2418 	}
2419 
2420 	qc->tf.command = ATA_CMD_PACKET;
2421 
2422 	/* no data, or PIO data xfer */
2423 	if (using_pio || nodata) {
2424 		if (nodata)
2425 			qc->tf.protocol = ATA_PROT_ATAPI_NODATA;
2426 		else
2427 			qc->tf.protocol = ATA_PROT_ATAPI;
2428 		qc->tf.lbam = (8 * 1024) & 0xff;
2429 		qc->tf.lbah = (8 * 1024) >> 8;
2430 	}
2431 
2432 	/* DMA data xfer */
2433 	else {
2434 		qc->tf.protocol = ATA_PROT_ATAPI_DMA;
2435 		qc->tf.feature |= ATAPI_PKT_DMA;
2436 
2437 		if (atapi_dmadir && (scmd->sc_data_direction != DMA_TO_DEVICE))
2438 			/* some SATA bridges need us to indicate data xfer direction */
2439 			qc->tf.feature |= ATAPI_DMADIR;
2440 	}
2441 
2442 	qc->nbytes = scmd->request_bufflen;
2443 
2444 	return 0;
2445 }
2446 
2447 static struct ata_device * ata_find_dev(struct ata_port *ap, int id)
2448 {
2449 	if (likely(id < ATA_MAX_DEVICES))
2450 		return &ap->device[id];
2451 	return NULL;
2452 }
2453 
2454 static struct ata_device * __ata_scsi_find_dev(struct ata_port *ap,
2455 					const struct scsi_device *scsidev)
2456 {
2457 	/* skip commands not addressed to targets we simulate */
2458 	if (unlikely(scsidev->channel || scsidev->lun))
2459 		return NULL;
2460 
2461 	return ata_find_dev(ap, scsidev->id);
2462 }
2463 
2464 /**
2465  *	ata_scsi_dev_enabled - determine if device is enabled
2466  *	@dev: ATA device
2467  *
2468  *	Determine if commands should be sent to the specified device.
2469  *
2470  *	LOCKING:
2471  *	spin_lock_irqsave(host lock)
2472  *
2473  *	RETURNS:
2474  *	0 if commands are not allowed / 1 if commands are allowed
2475  */
2476 
2477 static int ata_scsi_dev_enabled(struct ata_device *dev)
2478 {
2479 	if (unlikely(!ata_dev_enabled(dev)))
2480 		return 0;
2481 
2482 	if (!atapi_enabled || (dev->ap->flags & ATA_FLAG_NO_ATAPI)) {
2483 		if (unlikely(dev->class == ATA_DEV_ATAPI)) {
2484 			ata_dev_printk(dev, KERN_WARNING,
2485 				       "WARNING: ATAPI is %s, device ignored.\n",
2486 				       atapi_enabled ? "not supported with this driver" : "disabled");
2487 			return 0;
2488 		}
2489 	}
2490 
2491 	return 1;
2492 }
2493 
2494 /**
2495  *	ata_scsi_find_dev - lookup ata_device from scsi_cmnd
2496  *	@ap: ATA port to which the device is attached
2497  *	@scsidev: SCSI device from which we derive the ATA device
2498  *
2499  *	Given various information provided in struct scsi_cmnd,
2500  *	map that onto an ATA bus, and using that mapping
2501  *	determine which ata_device is associated with the
2502  *	SCSI command to be sent.
2503  *
2504  *	LOCKING:
2505  *	spin_lock_irqsave(host lock)
2506  *
2507  *	RETURNS:
2508  *	Associated ATA device, or %NULL if not found.
2509  */
2510 static struct ata_device *
2511 ata_scsi_find_dev(struct ata_port *ap, const struct scsi_device *scsidev)
2512 {
2513 	struct ata_device *dev = __ata_scsi_find_dev(ap, scsidev);
2514 
2515 	if (unlikely(!dev || !ata_scsi_dev_enabled(dev)))
2516 		return NULL;
2517 
2518 	return dev;
2519 }
2520 
2521 /*
2522  *	ata_scsi_map_proto - Map pass-thru protocol value to taskfile value.
2523  *	@byte1: Byte 1 from pass-thru CDB.
2524  *
2525  *	RETURNS:
2526  *	ATA_PROT_UNKNOWN if mapping failed/unimplemented, protocol otherwise.
2527  */
2528 static u8
2529 ata_scsi_map_proto(u8 byte1)
2530 {
2531 	switch((byte1 & 0x1e) >> 1) {
2532 		case 3:		/* Non-data */
2533 			return ATA_PROT_NODATA;
2534 
2535 		case 6:		/* DMA */
2536 			return ATA_PROT_DMA;
2537 
2538 		case 4:		/* PIO Data-in */
2539 		case 5:		/* PIO Data-out */
2540 			return ATA_PROT_PIO;
2541 
2542 		case 10:	/* Device Reset */
2543 		case 0:		/* Hard Reset */
2544 		case 1:		/* SRST */
2545 		case 2:		/* Bus Idle */
2546 		case 7:		/* Packet */
2547 		case 8:		/* DMA Queued */
2548 		case 9:		/* Device Diagnostic */
2549 		case 11:	/* UDMA Data-in */
2550 		case 12:	/* UDMA Data-Out */
2551 		case 13:	/* FPDMA */
2552 		default:	/* Reserved */
2553 			break;
2554 	}
2555 
2556 	return ATA_PROT_UNKNOWN;
2557 }
2558 
2559 /**
2560  *	ata_scsi_pass_thru - convert ATA pass-thru CDB to taskfile
2561  *	@qc: command structure to be initialized
2562  *
2563  *	Handles either 12 or 16-byte versions of the CDB.
2564  *
2565  *	RETURNS:
2566  *	Zero on success, non-zero on failure.
2567  */
2568 static unsigned int ata_scsi_pass_thru(struct ata_queued_cmd *qc)
2569 {
2570 	struct ata_taskfile *tf = &(qc->tf);
2571 	struct scsi_cmnd *scmd = qc->scsicmd;
2572 	struct ata_device *dev = qc->dev;
2573 	const u8 *cdb = scmd->cmnd;
2574 
2575 	if ((tf->protocol = ata_scsi_map_proto(cdb[1])) == ATA_PROT_UNKNOWN)
2576 		goto invalid_fld;
2577 
2578 	/* We may not issue DMA commands if no DMA mode is set */
2579 	if (tf->protocol == ATA_PROT_DMA && dev->dma_mode == 0)
2580 		goto invalid_fld;
2581 
2582 	if (cdb[1] & 0xe0)
2583 		/* PIO multi not supported yet */
2584 		goto invalid_fld;
2585 
2586 	/*
2587 	 * 12 and 16 byte CDBs use different offsets to
2588 	 * provide the various register values.
2589 	 */
2590 	if (cdb[0] == ATA_16) {
2591 		/*
2592 		 * 16-byte CDB - may contain extended commands.
2593 		 *
2594 		 * If that is the case, copy the upper byte register values.
2595 		 */
2596 		if (cdb[1] & 0x01) {
2597 			tf->hob_feature = cdb[3];
2598 			tf->hob_nsect = cdb[5];
2599 			tf->hob_lbal = cdb[7];
2600 			tf->hob_lbam = cdb[9];
2601 			tf->hob_lbah = cdb[11];
2602 			tf->flags |= ATA_TFLAG_LBA48;
2603 		} else
2604 			tf->flags &= ~ATA_TFLAG_LBA48;
2605 
2606 		/*
2607 		 * Always copy low byte, device and command registers.
2608 		 */
2609 		tf->feature = cdb[4];
2610 		tf->nsect = cdb[6];
2611 		tf->lbal = cdb[8];
2612 		tf->lbam = cdb[10];
2613 		tf->lbah = cdb[12];
2614 		tf->device = cdb[13];
2615 		tf->command = cdb[14];
2616 	} else {
2617 		/*
2618 		 * 12-byte CDB - incapable of extended commands.
2619 		 */
2620 		tf->flags &= ~ATA_TFLAG_LBA48;
2621 
2622 		tf->feature = cdb[3];
2623 		tf->nsect = cdb[4];
2624 		tf->lbal = cdb[5];
2625 		tf->lbam = cdb[6];
2626 		tf->lbah = cdb[7];
2627 		tf->device = cdb[8];
2628 		tf->command = cdb[9];
2629 	}
2630 	/*
2631 	 * If slave is possible, enforce correct master/slave bit
2632 	*/
2633 	if (qc->ap->flags & ATA_FLAG_SLAVE_POSS)
2634 		tf->device = qc->dev->devno ?
2635 			tf->device | ATA_DEV1 : tf->device & ~ATA_DEV1;
2636 
2637 	/*
2638 	 * Filter SET_FEATURES - XFER MODE command -- otherwise,
2639 	 * SET_FEATURES - XFER MODE must be preceded/succeeded
2640 	 * by an update to hardware-specific registers for each
2641 	 * controller (i.e. the reason for ->set_piomode(),
2642 	 * ->set_dmamode(), and ->post_set_mode() hooks).
2643 	 */
2644 	if ((tf->command == ATA_CMD_SET_FEATURES)
2645 	 && (tf->feature == SETFEATURES_XFER))
2646 		goto invalid_fld;
2647 
2648 	/*
2649 	 * Set flags so that all registers will be written,
2650 	 * and pass on write indication (used for PIO/DMA
2651 	 * setup.)
2652 	 */
2653 	tf->flags |= (ATA_TFLAG_ISADDR | ATA_TFLAG_DEVICE);
2654 
2655 	if (scmd->sc_data_direction == DMA_TO_DEVICE)
2656 		tf->flags |= ATA_TFLAG_WRITE;
2657 
2658 	/*
2659 	 * Set transfer length.
2660 	 *
2661 	 * TODO: find out if we need to do more here to
2662 	 *       cover scatter/gather case.
2663 	 */
2664 	qc->nsect = scmd->request_bufflen / ATA_SECT_SIZE;
2665 
2666 	/* request result TF */
2667 	qc->flags |= ATA_QCFLAG_RESULT_TF;
2668 
2669 	return 0;
2670 
2671  invalid_fld:
2672 	ata_scsi_set_sense(scmd, ILLEGAL_REQUEST, 0x24, 0x00);
2673 	/* "Invalid field in cdb" */
2674 	return 1;
2675 }
2676 
2677 /**
2678  *	ata_get_xlat_func - check if SCSI to ATA translation is possible
2679  *	@dev: ATA device
2680  *	@cmd: SCSI command opcode to consider
2681  *
2682  *	Look up the SCSI command given, and determine whether the
2683  *	SCSI command is to be translated or simulated.
2684  *
2685  *	RETURNS:
2686  *	Pointer to translation function if possible, %NULL if not.
2687  */
2688 
2689 static inline ata_xlat_func_t ata_get_xlat_func(struct ata_device *dev, u8 cmd)
2690 {
2691 	switch (cmd) {
2692 	case READ_6:
2693 	case READ_10:
2694 	case READ_16:
2695 
2696 	case WRITE_6:
2697 	case WRITE_10:
2698 	case WRITE_16:
2699 		return ata_scsi_rw_xlat;
2700 
2701 	case SYNCHRONIZE_CACHE:
2702 		if (ata_try_flush_cache(dev))
2703 			return ata_scsi_flush_xlat;
2704 		break;
2705 
2706 	case VERIFY:
2707 	case VERIFY_16:
2708 		return ata_scsi_verify_xlat;
2709 
2710 	case ATA_12:
2711 	case ATA_16:
2712 		return ata_scsi_pass_thru;
2713 
2714 	case START_STOP:
2715 		return ata_scsi_start_stop_xlat;
2716 	}
2717 
2718 	return NULL;
2719 }
2720 
2721 /**
2722  *	ata_scsi_dump_cdb - dump SCSI command contents to dmesg
2723  *	@ap: ATA port to which the command was being sent
2724  *	@cmd: SCSI command to dump
2725  *
2726  *	Prints the contents of a SCSI command via printk().
2727  */
2728 
2729 static inline void ata_scsi_dump_cdb(struct ata_port *ap,
2730 				     struct scsi_cmnd *cmd)
2731 {
2732 #ifdef ATA_DEBUG
2733 	struct scsi_device *scsidev = cmd->device;
2734 	u8 *scsicmd = cmd->cmnd;
2735 
2736 	DPRINTK("CDB (%u:%d,%d,%d) %02x %02x %02x %02x %02x %02x %02x %02x %02x\n",
2737 		ap->id,
2738 		scsidev->channel, scsidev->id, scsidev->lun,
2739 		scsicmd[0], scsicmd[1], scsicmd[2], scsicmd[3],
2740 		scsicmd[4], scsicmd[5], scsicmd[6], scsicmd[7],
2741 		scsicmd[8]);
2742 #endif
2743 }
2744 
2745 static inline int __ata_scsi_queuecmd(struct scsi_cmnd *scmd,
2746 				      void (*done)(struct scsi_cmnd *),
2747 				      struct ata_device *dev)
2748 {
2749 	int rc = 0;
2750 
2751 	if (unlikely(!scmd->cmd_len)) {
2752 		ata_dev_printk(dev, KERN_WARNING, "WARNING: zero len CDB\n");
2753 		scmd->result = DID_ERROR << 16;
2754 		done(scmd);
2755 		return 0;
2756 	}
2757 
2758 	if (dev->class == ATA_DEV_ATA) {
2759 		ata_xlat_func_t xlat_func = ata_get_xlat_func(dev,
2760 							      scmd->cmnd[0]);
2761 
2762 		if (xlat_func)
2763 			rc = ata_scsi_translate(dev, scmd, done, xlat_func);
2764 		else
2765 			ata_scsi_simulate(dev, scmd, done);
2766 	} else
2767 		rc = ata_scsi_translate(dev, scmd, done, atapi_xlat);
2768 
2769 	return rc;
2770 }
2771 
2772 /**
2773  *	ata_scsi_queuecmd - Issue SCSI cdb to libata-managed device
2774  *	@cmd: SCSI command to be sent
2775  *	@done: Completion function, called when command is complete
2776  *
2777  *	In some cases, this function translates SCSI commands into
2778  *	ATA taskfiles, and queues the taskfiles to be sent to
2779  *	hardware.  In other cases, this function simulates a
2780  *	SCSI device by evaluating and responding to certain
2781  *	SCSI commands.  This creates the overall effect of
2782  *	ATA and ATAPI devices appearing as SCSI devices.
2783  *
2784  *	LOCKING:
2785  *	Releases scsi-layer-held lock, and obtains host lock.
2786  *
2787  *	RETURNS:
2788  *	Return value from __ata_scsi_queuecmd() if @cmd can be queued,
2789  *	0 otherwise.
2790  */
2791 int ata_scsi_queuecmd(struct scsi_cmnd *cmd, void (*done)(struct scsi_cmnd *))
2792 {
2793 	struct ata_port *ap;
2794 	struct ata_device *dev;
2795 	struct scsi_device *scsidev = cmd->device;
2796 	struct Scsi_Host *shost = scsidev->host;
2797 	int rc = 0;
2798 
2799 	ap = ata_shost_to_port(shost);
2800 
2801 	spin_unlock(shost->host_lock);
2802 	spin_lock(ap->lock);
2803 
2804 	ata_scsi_dump_cdb(ap, cmd);
2805 
2806 	dev = ata_scsi_find_dev(ap, scsidev);
2807 	if (likely(dev))
2808 		rc = __ata_scsi_queuecmd(cmd, done, dev);
2809 	else {
2810 		cmd->result = (DID_BAD_TARGET << 16);
2811 		done(cmd);
2812 	}
2813 
2814 	spin_unlock(ap->lock);
2815 	spin_lock(shost->host_lock);
2816 	return rc;
2817 }
2818 
2819 /**
2820  *	ata_scsi_simulate - simulate SCSI command on ATA device
2821  *	@dev: the target device
2822  *	@cmd: SCSI command being sent to device.
2823  *	@done: SCSI command completion function.
2824  *
2825  *	Interprets and directly executes a select list of SCSI commands
2826  *	that can be handled internally.
2827  *
2828  *	LOCKING:
2829  *	spin_lock_irqsave(host lock)
2830  */
2831 
2832 void ata_scsi_simulate(struct ata_device *dev, struct scsi_cmnd *cmd,
2833 		      void (*done)(struct scsi_cmnd *))
2834 {
2835 	struct ata_scsi_args args;
2836 	const u8 *scsicmd = cmd->cmnd;
2837 
2838 	args.dev = dev;
2839 	args.id = dev->id;
2840 	args.cmd = cmd;
2841 	args.done = done;
2842 
2843 	switch(scsicmd[0]) {
2844 		/* no-op's, complete with success */
2845 		case SYNCHRONIZE_CACHE:
2846 		case REZERO_UNIT:
2847 		case SEEK_6:
2848 		case SEEK_10:
2849 		case TEST_UNIT_READY:
2850 		case FORMAT_UNIT:		/* FIXME: correct? */
2851 		case SEND_DIAGNOSTIC:		/* FIXME: correct? */
2852 			ata_scsi_rbuf_fill(&args, ata_scsiop_noop);
2853 			break;
2854 
2855 		case INQUIRY:
2856 			if (scsicmd[1] & 2)	           /* is CmdDt set?  */
2857 				ata_scsi_invalid_field(cmd, done);
2858 			else if ((scsicmd[1] & 1) == 0)    /* is EVPD clear? */
2859 				ata_scsi_rbuf_fill(&args, ata_scsiop_inq_std);
2860 			else if (scsicmd[2] == 0x00)
2861 				ata_scsi_rbuf_fill(&args, ata_scsiop_inq_00);
2862 			else if (scsicmd[2] == 0x80)
2863 				ata_scsi_rbuf_fill(&args, ata_scsiop_inq_80);
2864 			else if (scsicmd[2] == 0x83)
2865 				ata_scsi_rbuf_fill(&args, ata_scsiop_inq_83);
2866 			else
2867 				ata_scsi_invalid_field(cmd, done);
2868 			break;
2869 
2870 		case MODE_SENSE:
2871 		case MODE_SENSE_10:
2872 			ata_scsi_rbuf_fill(&args, ata_scsiop_mode_sense);
2873 			break;
2874 
2875 		case MODE_SELECT:	/* unconditionally return */
2876 		case MODE_SELECT_10:	/* bad-field-in-cdb */
2877 			ata_scsi_invalid_field(cmd, done);
2878 			break;
2879 
2880 		case READ_CAPACITY:
2881 			ata_scsi_rbuf_fill(&args, ata_scsiop_read_cap);
2882 			break;
2883 
2884 		case SERVICE_ACTION_IN:
2885 			if ((scsicmd[1] & 0x1f) == SAI_READ_CAPACITY_16)
2886 				ata_scsi_rbuf_fill(&args, ata_scsiop_read_cap);
2887 			else
2888 				ata_scsi_invalid_field(cmd, done);
2889 			break;
2890 
2891 		case REPORT_LUNS:
2892 			ata_scsi_rbuf_fill(&args, ata_scsiop_report_luns);
2893 			break;
2894 
2895 		/* mandatory commands we haven't implemented yet */
2896 		case REQUEST_SENSE:
2897 
2898 		/* all other commands */
2899 		default:
2900 			ata_scsi_set_sense(cmd, ILLEGAL_REQUEST, 0x20, 0x0);
2901 			/* "Invalid command operation code" */
2902 			done(cmd);
2903 			break;
2904 	}
2905 }
2906 
2907 void ata_scsi_scan_host(struct ata_port *ap)
2908 {
2909 	unsigned int i;
2910 
2911 	if (ap->flags & ATA_FLAG_DISABLED)
2912 		return;
2913 
2914 	for (i = 0; i < ATA_MAX_DEVICES; i++) {
2915 		struct ata_device *dev = &ap->device[i];
2916 		struct scsi_device *sdev;
2917 
2918 		if (!ata_dev_enabled(dev) || dev->sdev)
2919 			continue;
2920 
2921 		sdev = __scsi_add_device(ap->scsi_host, 0, i, 0, NULL);
2922 		if (!IS_ERR(sdev)) {
2923 			dev->sdev = sdev;
2924 			scsi_device_put(sdev);
2925 		}
2926 	}
2927 }
2928 
2929 /**
2930  *	ata_scsi_offline_dev - offline attached SCSI device
2931  *	@dev: ATA device to offline attached SCSI device for
2932  *
2933  *	This function is called from ata_eh_hotplug() and responsible
2934  *	for taking the SCSI device attached to @dev offline.  This
2935  *	function is called with host lock which protects dev->sdev
2936  *	against clearing.
2937  *
2938  *	LOCKING:
2939  *	spin_lock_irqsave(host lock)
2940  *
2941  *	RETURNS:
2942  *	1 if attached SCSI device exists, 0 otherwise.
2943  */
2944 int ata_scsi_offline_dev(struct ata_device *dev)
2945 {
2946 	if (dev->sdev) {
2947 		scsi_device_set_state(dev->sdev, SDEV_OFFLINE);
2948 		return 1;
2949 	}
2950 	return 0;
2951 }
2952 
2953 /**
2954  *	ata_scsi_remove_dev - remove attached SCSI device
2955  *	@dev: ATA device to remove attached SCSI device for
2956  *
2957  *	This function is called from ata_eh_scsi_hotplug() and
2958  *	responsible for removing the SCSI device attached to @dev.
2959  *
2960  *	LOCKING:
2961  *	Kernel thread context (may sleep).
2962  */
2963 static void ata_scsi_remove_dev(struct ata_device *dev)
2964 {
2965 	struct ata_port *ap = dev->ap;
2966 	struct scsi_device *sdev;
2967 	unsigned long flags;
2968 
2969 	/* Alas, we need to grab scan_mutex to ensure SCSI device
2970 	 * state doesn't change underneath us and thus
2971 	 * scsi_device_get() always succeeds.  The mutex locking can
2972 	 * be removed if there is __scsi_device_get() interface which
2973 	 * increments reference counts regardless of device state.
2974 	 */
2975 	mutex_lock(&ap->scsi_host->scan_mutex);
2976 	spin_lock_irqsave(ap->lock, flags);
2977 
2978 	/* clearing dev->sdev is protected by host lock */
2979 	sdev = dev->sdev;
2980 	dev->sdev = NULL;
2981 
2982 	if (sdev) {
2983 		/* If user initiated unplug races with us, sdev can go
2984 		 * away underneath us after the host lock and
2985 		 * scan_mutex are released.  Hold onto it.
2986 		 */
2987 		if (scsi_device_get(sdev) == 0) {
2988 			/* The following ensures the attached sdev is
2989 			 * offline on return from ata_scsi_offline_dev()
2990 			 * regardless it wins or loses the race
2991 			 * against this function.
2992 			 */
2993 			scsi_device_set_state(sdev, SDEV_OFFLINE);
2994 		} else {
2995 			WARN_ON(1);
2996 			sdev = NULL;
2997 		}
2998 	}
2999 
3000 	spin_unlock_irqrestore(ap->lock, flags);
3001 	mutex_unlock(&ap->scsi_host->scan_mutex);
3002 
3003 	if (sdev) {
3004 		ata_dev_printk(dev, KERN_INFO, "detaching (SCSI %s)\n",
3005 			       sdev->sdev_gendev.bus_id);
3006 
3007 		scsi_remove_device(sdev);
3008 		scsi_device_put(sdev);
3009 	}
3010 }
3011 
3012 /**
3013  *	ata_scsi_hotplug - SCSI part of hotplug
3014  *	@work: Pointer to ATA port to perform SCSI hotplug on
3015  *
3016  *	Perform SCSI part of hotplug.  It's executed from a separate
3017  *	workqueue after EH completes.  This is necessary because SCSI
3018  *	hot plugging requires working EH and hot unplugging is
3019  *	synchronized with hot plugging with a mutex.
3020  *
3021  *	LOCKING:
3022  *	Kernel thread context (may sleep).
3023  */
3024 void ata_scsi_hotplug(struct work_struct *work)
3025 {
3026 	struct ata_port *ap =
3027 		container_of(work, struct ata_port, hotplug_task.work);
3028 	int i;
3029 
3030 	if (ap->pflags & ATA_PFLAG_UNLOADING) {
3031 		DPRINTK("ENTER/EXIT - unloading\n");
3032 		return;
3033 	}
3034 
3035 	DPRINTK("ENTER\n");
3036 
3037 	/* unplug detached devices */
3038 	for (i = 0; i < ATA_MAX_DEVICES; i++) {
3039 		struct ata_device *dev = &ap->device[i];
3040 		unsigned long flags;
3041 
3042 		if (!(dev->flags & ATA_DFLAG_DETACHED))
3043 			continue;
3044 
3045 		spin_lock_irqsave(ap->lock, flags);
3046 		dev->flags &= ~ATA_DFLAG_DETACHED;
3047 		spin_unlock_irqrestore(ap->lock, flags);
3048 
3049 		ata_scsi_remove_dev(dev);
3050 	}
3051 
3052 	/* scan for new ones */
3053 	ata_scsi_scan_host(ap);
3054 
3055 	/* If we scanned while EH was in progress, scan would have
3056 	 * failed silently.  Requeue if there are enabled but
3057 	 * unattached devices.
3058 	 */
3059 	for (i = 0; i < ATA_MAX_DEVICES; i++) {
3060 		struct ata_device *dev = &ap->device[i];
3061 		if (ata_dev_enabled(dev) && !dev->sdev) {
3062 			queue_delayed_work(ata_aux_wq, &ap->hotplug_task, HZ);
3063 			break;
3064 		}
3065 	}
3066 
3067 	DPRINTK("EXIT\n");
3068 }
3069 
3070 /**
3071  *	ata_scsi_user_scan - indication for user-initiated bus scan
3072  *	@shost: SCSI host to scan
3073  *	@channel: Channel to scan
3074  *	@id: ID to scan
3075  *	@lun: LUN to scan
3076  *
3077  *	This function is called when user explicitly requests bus
3078  *	scan.  Set probe pending flag and invoke EH.
3079  *
3080  *	LOCKING:
3081  *	SCSI layer (we don't care)
3082  *
3083  *	RETURNS:
3084  *	Zero.
3085  */
3086 static int ata_scsi_user_scan(struct Scsi_Host *shost, unsigned int channel,
3087 			      unsigned int id, unsigned int lun)
3088 {
3089 	struct ata_port *ap = ata_shost_to_port(shost);
3090 	unsigned long flags;
3091 	int rc = 0;
3092 
3093 	if (!ap->ops->error_handler)
3094 		return -EOPNOTSUPP;
3095 
3096 	if ((channel != SCAN_WILD_CARD && channel != 0) ||
3097 	    (lun != SCAN_WILD_CARD && lun != 0))
3098 		return -EINVAL;
3099 
3100 	spin_lock_irqsave(ap->lock, flags);
3101 
3102 	if (id == SCAN_WILD_CARD) {
3103 		ap->eh_info.probe_mask |= (1 << ATA_MAX_DEVICES) - 1;
3104 		ap->eh_info.action |= ATA_EH_SOFTRESET;
3105 	} else {
3106 		struct ata_device *dev = ata_find_dev(ap, id);
3107 
3108 		if (dev) {
3109 			ap->eh_info.probe_mask |= 1 << dev->devno;
3110 			ap->eh_info.action |= ATA_EH_SOFTRESET;
3111 			ap->eh_info.flags |= ATA_EHI_RESUME_LINK;
3112 		} else
3113 			rc = -EINVAL;
3114 	}
3115 
3116 	if (rc == 0) {
3117 		ata_port_schedule_eh(ap);
3118 		spin_unlock_irqrestore(ap->lock, flags);
3119 		ata_port_wait_eh(ap);
3120 	} else
3121 		spin_unlock_irqrestore(ap->lock, flags);
3122 
3123 	return rc;
3124 }
3125 
3126 /**
3127  *	ata_scsi_dev_rescan - initiate scsi_rescan_device()
3128  *	@work: Pointer to ATA port to perform scsi_rescan_device()
3129  *
3130  *	After ATA pass thru (SAT) commands are executed successfully,
3131  *	libata need to propagate the changes to SCSI layer.  This
3132  *	function must be executed from ata_aux_wq such that sdev
3133  *	attach/detach don't race with rescan.
3134  *
3135  *	LOCKING:
3136  *	Kernel thread context (may sleep).
3137  */
3138 void ata_scsi_dev_rescan(struct work_struct *work)
3139 {
3140 	struct ata_port *ap =
3141 		container_of(work, struct ata_port, scsi_rescan_task);
3142 	unsigned long flags;
3143 	unsigned int i;
3144 
3145 	spin_lock_irqsave(ap->lock, flags);
3146 
3147 	for (i = 0; i < ATA_MAX_DEVICES; i++) {
3148 		struct ata_device *dev = &ap->device[i];
3149 		struct scsi_device *sdev = dev->sdev;
3150 
3151 		if (!ata_dev_enabled(dev) || !sdev)
3152 			continue;
3153 		if (scsi_device_get(sdev))
3154 			continue;
3155 
3156 		spin_unlock_irqrestore(ap->lock, flags);
3157 		scsi_rescan_device(&(sdev->sdev_gendev));
3158 		scsi_device_put(sdev);
3159 		spin_lock_irqsave(ap->lock, flags);
3160 	}
3161 
3162 	spin_unlock_irqrestore(ap->lock, flags);
3163 }
3164 
3165 /**
3166  *	ata_sas_port_alloc - Allocate port for a SAS attached SATA device
3167  *	@host: ATA host container for all SAS ports
3168  *	@port_info: Information from low-level host driver
3169  *	@shost: SCSI host that the scsi device is attached to
3170  *
3171  *	LOCKING:
3172  *	PCI/etc. bus probe sem.
3173  *
3174  *	RETURNS:
3175  *	ata_port pointer on success / NULL on failure.
3176  */
3177 
3178 struct ata_port *ata_sas_port_alloc(struct ata_host *host,
3179 				    struct ata_port_info *port_info,
3180 				    struct Scsi_Host *shost)
3181 {
3182 	struct ata_port *ap = kzalloc(sizeof(*ap), GFP_KERNEL);
3183 	struct ata_probe_ent *ent;
3184 
3185 	if (!ap)
3186 		return NULL;
3187 
3188 	ent = ata_probe_ent_alloc(host->dev, port_info);
3189 	if (!ent) {
3190 		kfree(ap);
3191 		return NULL;
3192 	}
3193 
3194 	ata_port_init(ap, host, ent, 0);
3195 	ap->lock = shost->host_lock;
3196 	kfree(ent);
3197 	return ap;
3198 }
3199 EXPORT_SYMBOL_GPL(ata_sas_port_alloc);
3200 
3201 /**
3202  *	ata_sas_port_start - Set port up for dma.
3203  *	@ap: Port to initialize
3204  *
3205  *	Called just after data structures for each port are
3206  *	initialized.  Allocates DMA pad.
3207  *
3208  *	May be used as the port_start() entry in ata_port_operations.
3209  *
3210  *	LOCKING:
3211  *	Inherited from caller.
3212  */
3213 int ata_sas_port_start(struct ata_port *ap)
3214 {
3215 	return ata_pad_alloc(ap, ap->dev);
3216 }
3217 EXPORT_SYMBOL_GPL(ata_sas_port_start);
3218 
3219 /**
3220  *	ata_port_stop - Undo ata_sas_port_start()
3221  *	@ap: Port to shut down
3222  *
3223  *	Frees the DMA pad.
3224  *
3225  *	May be used as the port_stop() entry in ata_port_operations.
3226  *
3227  *	LOCKING:
3228  *	Inherited from caller.
3229  */
3230 
3231 void ata_sas_port_stop(struct ata_port *ap)
3232 {
3233 	ata_pad_free(ap, ap->dev);
3234 }
3235 EXPORT_SYMBOL_GPL(ata_sas_port_stop);
3236 
3237 /**
3238  *	ata_sas_port_init - Initialize a SATA device
3239  *	@ap: SATA port to initialize
3240  *
3241  *	LOCKING:
3242  *	PCI/etc. bus probe sem.
3243  *
3244  *	RETURNS:
3245  *	Zero on success, non-zero on error.
3246  */
3247 
3248 int ata_sas_port_init(struct ata_port *ap)
3249 {
3250 	int rc = ap->ops->port_start(ap);
3251 
3252 	if (!rc)
3253 		rc = ata_bus_probe(ap);
3254 
3255 	return rc;
3256 }
3257 EXPORT_SYMBOL_GPL(ata_sas_port_init);
3258 
3259 /**
3260  *	ata_sas_port_destroy - Destroy a SATA port allocated by ata_sas_port_alloc
3261  *	@ap: SATA port to destroy
3262  *
3263  */
3264 
3265 void ata_sas_port_destroy(struct ata_port *ap)
3266 {
3267 	ap->ops->port_stop(ap);
3268 	kfree(ap);
3269 }
3270 EXPORT_SYMBOL_GPL(ata_sas_port_destroy);
3271 
3272 /**
3273  *	ata_sas_slave_configure - Default slave_config routine for libata devices
3274  *	@sdev: SCSI device to configure
3275  *	@ap: ATA port to which SCSI device is attached
3276  *
3277  *	RETURNS:
3278  *	Zero.
3279  */
3280 
3281 int ata_sas_slave_configure(struct scsi_device *sdev, struct ata_port *ap)
3282 {
3283 	ata_scsi_sdev_config(sdev);
3284 	ata_scsi_dev_config(sdev, ap->device);
3285 	return 0;
3286 }
3287 EXPORT_SYMBOL_GPL(ata_sas_slave_configure);
3288 
3289 /**
3290  *	ata_sas_queuecmd - Issue SCSI cdb to libata-managed device
3291  *	@cmd: SCSI command to be sent
3292  *	@done: Completion function, called when command is complete
3293  *	@ap:	ATA port to which the command is being sent
3294  *
3295  *	RETURNS:
3296  *	Return value from __ata_scsi_queuecmd() if @cmd can be queued,
3297  *	0 otherwise.
3298  */
3299 
3300 int ata_sas_queuecmd(struct scsi_cmnd *cmd, void (*done)(struct scsi_cmnd *),
3301 		     struct ata_port *ap)
3302 {
3303 	int rc = 0;
3304 
3305 	ata_scsi_dump_cdb(ap, cmd);
3306 
3307 	if (likely(ata_scsi_dev_enabled(ap->device)))
3308 		rc = __ata_scsi_queuecmd(cmd, done, ap->device);
3309 	else {
3310 		cmd->result = (DID_BAD_TARGET << 16);
3311 		done(cmd);
3312 	}
3313 	return rc;
3314 }
3315 EXPORT_SYMBOL_GPL(ata_sas_queuecmd);
3316