xref: /openbmc/linux/drivers/scsi/libsas/sas_ata.c (revision 25985edc)
1 /*
2  * Support for SATA devices on Serial Attached SCSI (SAS) controllers
3  *
4  * Copyright (C) 2006 IBM Corporation
5  *
6  * Written by: Darrick J. Wong <djwong@us.ibm.com>, IBM Corporation
7  *
8  * This program is free software; you can redistribute it and/or
9  * modify it under the terms of the GNU General Public License as
10  * published by the Free Software Foundation; either version 2 of the
11  * License, or (at your option) any later version.
12  *
13  * This program is distributed in the hope that it will be useful, but
14  * WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
16  * General Public License for more details.
17  *
18  * You should have received a copy of the GNU General Public License
19  * along with this program; if not, write to the Free Software
20  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
21  * USA
22  */
23 
24 #include <linux/scatterlist.h>
25 #include <linux/slab.h>
26 
27 #include <scsi/sas_ata.h>
28 #include "sas_internal.h"
29 #include <scsi/scsi_host.h>
30 #include <scsi/scsi_device.h>
31 #include <scsi/scsi_tcq.h>
32 #include <scsi/scsi.h>
33 #include <scsi/scsi_transport.h>
34 #include <scsi/scsi_transport_sas.h>
35 #include "../scsi_sas_internal.h"
36 #include "../scsi_transport_api.h"
37 #include <scsi/scsi_eh.h>
38 
39 static enum ata_completion_errors sas_to_ata_err(struct task_status_struct *ts)
40 {
41 	/* Cheesy attempt to translate SAS errors into ATA.  Hah! */
42 
43 	/* transport error */
44 	if (ts->resp == SAS_TASK_UNDELIVERED)
45 		return AC_ERR_ATA_BUS;
46 
47 	/* ts->resp == SAS_TASK_COMPLETE */
48 	/* task delivered, what happened afterwards? */
49 	switch (ts->stat) {
50 		case SAS_DEV_NO_RESPONSE:
51 			return AC_ERR_TIMEOUT;
52 
53 		case SAS_INTERRUPTED:
54 		case SAS_PHY_DOWN:
55 		case SAS_NAK_R_ERR:
56 			return AC_ERR_ATA_BUS;
57 
58 
59 		case SAS_DATA_UNDERRUN:
60 			/*
61 			 * Some programs that use the taskfile interface
62 			 * (smartctl in particular) can cause underrun
63 			 * problems.  Ignore these errors, perhaps at our
64 			 * peril.
65 			 */
66 			return 0;
67 
68 		case SAS_DATA_OVERRUN:
69 		case SAS_QUEUE_FULL:
70 		case SAS_DEVICE_UNKNOWN:
71 		case SAS_SG_ERR:
72 			return AC_ERR_INVALID;
73 
74 		case SAS_OPEN_TO:
75 		case SAS_OPEN_REJECT:
76 			SAS_DPRINTK("%s: Saw error %d.  What to do?\n",
77 				    __func__, ts->stat);
78 			return AC_ERR_OTHER;
79 
80 		case SAM_STAT_CHECK_CONDITION:
81 		case SAS_ABORTED_TASK:
82 			return AC_ERR_DEV;
83 
84 		case SAS_PROTO_RESPONSE:
85 			/* This means the ending_fis has the error
86 			 * value; return 0 here to collect it */
87 			return 0;
88 		default:
89 			return 0;
90 	}
91 }
92 
93 static void sas_ata_task_done(struct sas_task *task)
94 {
95 	struct ata_queued_cmd *qc = task->uldd_task;
96 	struct domain_device *dev;
97 	struct task_status_struct *stat = &task->task_status;
98 	struct ata_task_resp *resp = (struct ata_task_resp *)stat->buf;
99 	struct sas_ha_struct *sas_ha;
100 	enum ata_completion_errors ac;
101 	unsigned long flags;
102 
103 	if (!qc)
104 		goto qc_already_gone;
105 
106 	dev = qc->ap->private_data;
107 	sas_ha = dev->port->ha;
108 
109 	spin_lock_irqsave(dev->sata_dev.ap->lock, flags);
110 	if (stat->stat == SAS_PROTO_RESPONSE || stat->stat == SAM_STAT_GOOD ||
111 	    ((stat->stat == SAM_STAT_CHECK_CONDITION &&
112 	      dev->sata_dev.command_set == ATAPI_COMMAND_SET))) {
113 		ata_tf_from_fis(resp->ending_fis, &dev->sata_dev.tf);
114 		qc->err_mask |= ac_err_mask(dev->sata_dev.tf.command);
115 		dev->sata_dev.sstatus = resp->sstatus;
116 		dev->sata_dev.serror = resp->serror;
117 		dev->sata_dev.scontrol = resp->scontrol;
118 	} else {
119 		ac = sas_to_ata_err(stat);
120 		if (ac) {
121 			SAS_DPRINTK("%s: SAS error %x\n", __func__,
122 				    stat->stat);
123 			/* We saw a SAS error. Send a vague error. */
124 			qc->err_mask = ac;
125 			dev->sata_dev.tf.feature = 0x04; /* status err */
126 			dev->sata_dev.tf.command = ATA_ERR;
127 		}
128 	}
129 
130 	qc->lldd_task = NULL;
131 	if (qc->scsicmd)
132 		ASSIGN_SAS_TASK(qc->scsicmd, NULL);
133 	ata_qc_complete(qc);
134 	spin_unlock_irqrestore(dev->sata_dev.ap->lock, flags);
135 
136 	/*
137 	 * If the sas_task has an ata qc, a scsi_cmnd and the aborted
138 	 * flag is set, then we must have come in via the libsas EH
139 	 * functions.  When we exit this function, we need to put the
140 	 * scsi_cmnd on the list of finished errors.  The ata_qc_complete
141 	 * call cleans up the libata side of things but we're protected
142 	 * from the scsi_cmnd going away because the scsi_cmnd is owned
143 	 * by the EH, making libata's call to scsi_done a NOP.
144 	 */
145 	spin_lock_irqsave(&task->task_state_lock, flags);
146 	if (qc->scsicmd && task->task_state_flags & SAS_TASK_STATE_ABORTED)
147 		scsi_eh_finish_cmd(qc->scsicmd, &sas_ha->eh_done_q);
148 	spin_unlock_irqrestore(&task->task_state_lock, flags);
149 
150 qc_already_gone:
151 	list_del_init(&task->list);
152 	sas_free_task(task);
153 }
154 
155 static unsigned int sas_ata_qc_issue(struct ata_queued_cmd *qc)
156 {
157 	int res;
158 	struct sas_task *task;
159 	struct domain_device *dev = qc->ap->private_data;
160 	struct sas_ha_struct *sas_ha = dev->port->ha;
161 	struct Scsi_Host *host = sas_ha->core.shost;
162 	struct sas_internal *i = to_sas_internal(host->transportt);
163 	struct scatterlist *sg;
164 	unsigned int xfer = 0;
165 	unsigned int si;
166 
167 	/* If the device fell off, no sense in issuing commands */
168 	if (dev->gone)
169 		return AC_ERR_SYSTEM;
170 
171 	task = sas_alloc_task(GFP_ATOMIC);
172 	if (!task)
173 		return AC_ERR_SYSTEM;
174 	task->dev = dev;
175 	task->task_proto = SAS_PROTOCOL_STP;
176 	task->task_done = sas_ata_task_done;
177 
178 	if (qc->tf.command == ATA_CMD_FPDMA_WRITE ||
179 	    qc->tf.command == ATA_CMD_FPDMA_READ) {
180 		/* Need to zero out the tag libata assigned us */
181 		qc->tf.nsect = 0;
182 	}
183 
184 	ata_tf_to_fis(&qc->tf, 1, 0, (u8*)&task->ata_task.fis);
185 	task->uldd_task = qc;
186 	if (ata_is_atapi(qc->tf.protocol)) {
187 		memcpy(task->ata_task.atapi_packet, qc->cdb, qc->dev->cdb_len);
188 		task->total_xfer_len = qc->nbytes;
189 		task->num_scatter = qc->n_elem;
190 	} else {
191 		for_each_sg(qc->sg, sg, qc->n_elem, si)
192 			xfer += sg->length;
193 
194 		task->total_xfer_len = xfer;
195 		task->num_scatter = si;
196 	}
197 
198 	task->data_dir = qc->dma_dir;
199 	task->scatter = qc->sg;
200 	task->ata_task.retry_count = 1;
201 	task->task_state_flags = SAS_TASK_STATE_PENDING;
202 	qc->lldd_task = task;
203 
204 	switch (qc->tf.protocol) {
205 	case ATA_PROT_NCQ:
206 		task->ata_task.use_ncq = 1;
207 		/* fall through */
208 	case ATAPI_PROT_DMA:
209 	case ATA_PROT_DMA:
210 		task->ata_task.dma_xfer = 1;
211 		break;
212 	}
213 
214 	if (qc->scsicmd)
215 		ASSIGN_SAS_TASK(qc->scsicmd, task);
216 
217 	if (sas_ha->lldd_max_execute_num < 2)
218 		res = i->dft->lldd_execute_task(task, 1, GFP_ATOMIC);
219 	else
220 		res = sas_queue_up(task);
221 
222 	/* Examine */
223 	if (res) {
224 		SAS_DPRINTK("lldd_execute_task returned: %d\n", res);
225 
226 		if (qc->scsicmd)
227 			ASSIGN_SAS_TASK(qc->scsicmd, NULL);
228 		sas_free_task(task);
229 		return AC_ERR_SYSTEM;
230 	}
231 
232 	return 0;
233 }
234 
235 static bool sas_ata_qc_fill_rtf(struct ata_queued_cmd *qc)
236 {
237 	struct domain_device *dev = qc->ap->private_data;
238 
239 	memcpy(&qc->result_tf, &dev->sata_dev.tf, sizeof(qc->result_tf));
240 	return true;
241 }
242 
243 static int sas_ata_hard_reset(struct ata_link *link, unsigned int *class,
244 			       unsigned long deadline)
245 {
246 	struct ata_port *ap = link->ap;
247 	struct domain_device *dev = ap->private_data;
248 	struct sas_internal *i =
249 		to_sas_internal(dev->port->ha->core.shost->transportt);
250 	int res = TMF_RESP_FUNC_FAILED;
251 	int ret = 0;
252 
253 	if (i->dft->lldd_I_T_nexus_reset)
254 		res = i->dft->lldd_I_T_nexus_reset(dev);
255 
256 	if (res != TMF_RESP_FUNC_COMPLETE) {
257 		SAS_DPRINTK("%s: Unable to reset I T nexus?\n", __func__);
258 		ret = -EAGAIN;
259 	}
260 
261 	switch (dev->sata_dev.command_set) {
262 		case ATA_COMMAND_SET:
263 			SAS_DPRINTK("%s: Found ATA device.\n", __func__);
264 			*class = ATA_DEV_ATA;
265 			break;
266 		case ATAPI_COMMAND_SET:
267 			SAS_DPRINTK("%s: Found ATAPI device.\n", __func__);
268 			*class = ATA_DEV_ATAPI;
269 			break;
270 		default:
271 			SAS_DPRINTK("%s: Unknown SATA command set: %d.\n",
272 				    __func__,
273 				    dev->sata_dev.command_set);
274 			*class = ATA_DEV_UNKNOWN;
275 			break;
276 	}
277 
278 	ap->cbl = ATA_CBL_SATA;
279 	return ret;
280 }
281 
282 static void sas_ata_post_internal(struct ata_queued_cmd *qc)
283 {
284 	if (qc->flags & ATA_QCFLAG_FAILED)
285 		qc->err_mask |= AC_ERR_OTHER;
286 
287 	if (qc->err_mask) {
288 		/*
289 		 * Find the sas_task and kill it.  By this point,
290 		 * libata has decided to kill the qc, so we needn't
291 		 * bother with sas_ata_task_done.  But we still
292 		 * ought to abort the task.
293 		 */
294 		struct sas_task *task = qc->lldd_task;
295 		unsigned long flags;
296 
297 		qc->lldd_task = NULL;
298 		if (task) {
299 			/* Should this be a AT(API) device reset? */
300 			spin_lock_irqsave(&task->task_state_lock, flags);
301 			task->task_state_flags |= SAS_TASK_NEED_DEV_RESET;
302 			spin_unlock_irqrestore(&task->task_state_lock, flags);
303 
304 			task->uldd_task = NULL;
305 			__sas_task_abort(task);
306 		}
307 	}
308 }
309 
310 static struct ata_port_operations sas_sata_ops = {
311 	.prereset		= ata_std_prereset,
312 	.softreset		= NULL,
313 	.hardreset		= sas_ata_hard_reset,
314 	.postreset		= ata_std_postreset,
315 	.error_handler		= ata_std_error_handler,
316 	.post_internal_cmd	= sas_ata_post_internal,
317 	.qc_defer               = ata_std_qc_defer,
318 	.qc_prep		= ata_noop_qc_prep,
319 	.qc_issue		= sas_ata_qc_issue,
320 	.qc_fill_rtf		= sas_ata_qc_fill_rtf,
321 	.port_start		= ata_sas_port_start,
322 	.port_stop		= ata_sas_port_stop,
323 };
324 
325 static struct ata_port_info sata_port_info = {
326 	.flags = ATA_FLAG_SATA | ATA_FLAG_PIO_DMA | ATA_FLAG_NCQ,
327 	.pio_mask = ATA_PIO4,
328 	.mwdma_mask = ATA_MWDMA2,
329 	.udma_mask = ATA_UDMA6,
330 	.port_ops = &sas_sata_ops
331 };
332 
333 int sas_ata_init_host_and_port(struct domain_device *found_dev,
334 			       struct scsi_target *starget)
335 {
336 	struct Scsi_Host *shost = dev_to_shost(&starget->dev);
337 	struct sas_ha_struct *ha = SHOST_TO_SAS_HA(shost);
338 	struct ata_port *ap;
339 
340 	ata_host_init(&found_dev->sata_dev.ata_host,
341 		      ha->dev,
342 		      sata_port_info.flags,
343 		      &sas_sata_ops);
344 	ap = ata_sas_port_alloc(&found_dev->sata_dev.ata_host,
345 				&sata_port_info,
346 				shost);
347 	if (!ap) {
348 		SAS_DPRINTK("ata_sas_port_alloc failed.\n");
349 		return -ENODEV;
350 	}
351 
352 	ap->private_data = found_dev;
353 	ap->cbl = ATA_CBL_SATA;
354 	ap->scsi_host = shost;
355 	found_dev->sata_dev.ap = ap;
356 
357 	return 0;
358 }
359 
360 void sas_ata_task_abort(struct sas_task *task)
361 {
362 	struct ata_queued_cmd *qc = task->uldd_task;
363 	struct completion *waiting;
364 
365 	/* Bounce SCSI-initiated commands to the SCSI EH */
366 	if (qc->scsicmd) {
367 		struct request_queue *q = qc->scsicmd->device->request_queue;
368 		unsigned long flags;
369 
370 		spin_lock_irqsave(q->queue_lock, flags);
371 		blk_abort_request(qc->scsicmd->request);
372 		spin_unlock_irqrestore(q->queue_lock, flags);
373 		scsi_schedule_eh(qc->scsicmd->device->host);
374 		return;
375 	}
376 
377 	/* Internal command, fake a timeout and complete. */
378 	qc->flags &= ~ATA_QCFLAG_ACTIVE;
379 	qc->flags |= ATA_QCFLAG_FAILED;
380 	qc->err_mask |= AC_ERR_TIMEOUT;
381 	waiting = qc->private_data;
382 	complete(waiting);
383 }
384 
385 static void sas_task_timedout(unsigned long _task)
386 {
387 	struct sas_task *task = (void *) _task;
388 	unsigned long flags;
389 
390 	spin_lock_irqsave(&task->task_state_lock, flags);
391 	if (!(task->task_state_flags & SAS_TASK_STATE_DONE))
392 		task->task_state_flags |= SAS_TASK_STATE_ABORTED;
393 	spin_unlock_irqrestore(&task->task_state_lock, flags);
394 
395 	complete(&task->completion);
396 }
397 
398 static void sas_disc_task_done(struct sas_task *task)
399 {
400 	if (!del_timer(&task->timer))
401 		return;
402 	complete(&task->completion);
403 }
404 
405 #define SAS_DEV_TIMEOUT 10
406 
407 /**
408  * sas_execute_task -- Basic task processing for discovery
409  * @task: the task to be executed
410  * @buffer: pointer to buffer to do I/O
411  * @size: size of @buffer
412  * @dma_dir: DMA direction.  DMA_xxx
413  */
414 static int sas_execute_task(struct sas_task *task, void *buffer, int size,
415 			    enum dma_data_direction dma_dir)
416 {
417 	int res = 0;
418 	struct scatterlist *scatter = NULL;
419 	struct task_status_struct *ts = &task->task_status;
420 	int num_scatter = 0;
421 	int retries = 0;
422 	struct sas_internal *i =
423 		to_sas_internal(task->dev->port->ha->core.shost->transportt);
424 
425 	if (dma_dir != DMA_NONE) {
426 		scatter = kzalloc(sizeof(*scatter), GFP_KERNEL);
427 		if (!scatter)
428 			goto out;
429 
430 		sg_init_one(scatter, buffer, size);
431 		num_scatter = 1;
432 	}
433 
434 	task->task_proto = task->dev->tproto;
435 	task->scatter = scatter;
436 	task->num_scatter = num_scatter;
437 	task->total_xfer_len = size;
438 	task->data_dir = dma_dir;
439 	task->task_done = sas_disc_task_done;
440 	if (dma_dir != DMA_NONE &&
441 	    sas_protocol_ata(task->task_proto)) {
442 		task->num_scatter = dma_map_sg(task->dev->port->ha->dev,
443 					       task->scatter,
444 					       task->num_scatter,
445 					       task->data_dir);
446 	}
447 
448 	for (retries = 0; retries < 5; retries++) {
449 		task->task_state_flags = SAS_TASK_STATE_PENDING;
450 		init_completion(&task->completion);
451 
452 		task->timer.data = (unsigned long) task;
453 		task->timer.function = sas_task_timedout;
454 		task->timer.expires = jiffies + SAS_DEV_TIMEOUT*HZ;
455 		add_timer(&task->timer);
456 
457 		res = i->dft->lldd_execute_task(task, 1, GFP_KERNEL);
458 		if (res) {
459 			del_timer(&task->timer);
460 			SAS_DPRINTK("executing SAS discovery task failed:%d\n",
461 				    res);
462 			goto ex_err;
463 		}
464 		wait_for_completion(&task->completion);
465 		res = -ECOMM;
466 		if (task->task_state_flags & SAS_TASK_STATE_ABORTED) {
467 			int res2;
468 			SAS_DPRINTK("task aborted, flags:0x%x\n",
469 				    task->task_state_flags);
470 			res2 = i->dft->lldd_abort_task(task);
471 			SAS_DPRINTK("came back from abort task\n");
472 			if (!(task->task_state_flags & SAS_TASK_STATE_DONE)) {
473 				if (res2 == TMF_RESP_FUNC_COMPLETE)
474 					continue; /* Retry the task */
475 				else
476 					goto ex_err;
477 			}
478 		}
479 		if (task->task_status.stat == SAM_STAT_BUSY ||
480 			   task->task_status.stat == SAM_STAT_TASK_SET_FULL ||
481 			   task->task_status.stat == SAS_QUEUE_FULL) {
482 			SAS_DPRINTK("task: q busy, sleeping...\n");
483 			schedule_timeout_interruptible(HZ);
484 		} else if (task->task_status.stat == SAM_STAT_CHECK_CONDITION) {
485 			struct scsi_sense_hdr shdr;
486 
487 			if (!scsi_normalize_sense(ts->buf, ts->buf_valid_size,
488 						  &shdr)) {
489 				SAS_DPRINTK("couldn't normalize sense\n");
490 				continue;
491 			}
492 			if ((shdr.sense_key == 6 && shdr.asc == 0x29) ||
493 			    (shdr.sense_key == 2 && shdr.asc == 4 &&
494 			     shdr.ascq == 1)) {
495 				SAS_DPRINTK("device %016llx LUN: %016llx "
496 					    "powering up or not ready yet, "
497 					    "sleeping...\n",
498 					    SAS_ADDR(task->dev->sas_addr),
499 					    SAS_ADDR(task->ssp_task.LUN));
500 
501 				schedule_timeout_interruptible(5*HZ);
502 			} else if (shdr.sense_key == 1) {
503 				res = 0;
504 				break;
505 			} else if (shdr.sense_key == 5) {
506 				break;
507 			} else {
508 				SAS_DPRINTK("dev %016llx LUN: %016llx "
509 					    "sense key:0x%x ASC:0x%x ASCQ:0x%x"
510 					    "\n",
511 					    SAS_ADDR(task->dev->sas_addr),
512 					    SAS_ADDR(task->ssp_task.LUN),
513 					    shdr.sense_key,
514 					    shdr.asc, shdr.ascq);
515 			}
516 		} else if (task->task_status.resp != SAS_TASK_COMPLETE ||
517 			   task->task_status.stat != SAM_STAT_GOOD) {
518 			SAS_DPRINTK("task finished with resp:0x%x, "
519 				    "stat:0x%x\n",
520 				    task->task_status.resp,
521 				    task->task_status.stat);
522 			goto ex_err;
523 		} else {
524 			res = 0;
525 			break;
526 		}
527 	}
528 ex_err:
529 	if (dma_dir != DMA_NONE) {
530 		if (sas_protocol_ata(task->task_proto))
531 			dma_unmap_sg(task->dev->port->ha->dev,
532 				     task->scatter, task->num_scatter,
533 				     task->data_dir);
534 		kfree(scatter);
535 	}
536 out:
537 	return res;
538 }
539 
540 /* ---------- SATA ---------- */
541 
542 static void sas_get_ata_command_set(struct domain_device *dev)
543 {
544 	struct dev_to_host_fis *fis =
545 		(struct dev_to_host_fis *) dev->frame_rcvd;
546 
547 	if ((fis->sector_count == 1 && /* ATA */
548 	     fis->lbal         == 1 &&
549 	     fis->lbam         == 0 &&
550 	     fis->lbah         == 0 &&
551 	     fis->device       == 0)
552 	    ||
553 	    (fis->sector_count == 0 && /* CE-ATA (mATA) */
554 	     fis->lbal         == 0 &&
555 	     fis->lbam         == 0xCE &&
556 	     fis->lbah         == 0xAA &&
557 	     (fis->device & ~0x10) == 0))
558 
559 		dev->sata_dev.command_set = ATA_COMMAND_SET;
560 
561 	else if ((fis->interrupt_reason == 1 &&	/* ATAPI */
562 		  fis->lbal             == 1 &&
563 		  fis->byte_count_low   == 0x14 &&
564 		  fis->byte_count_high  == 0xEB &&
565 		  (fis->device & ~0x10) == 0))
566 
567 		dev->sata_dev.command_set = ATAPI_COMMAND_SET;
568 
569 	else if ((fis->sector_count == 1 && /* SEMB */
570 		  fis->lbal         == 1 &&
571 		  fis->lbam         == 0x3C &&
572 		  fis->lbah         == 0xC3 &&
573 		  fis->device       == 0)
574 		||
575 		 (fis->interrupt_reason == 1 &&	/* SATA PM */
576 		  fis->lbal             == 1 &&
577 		  fis->byte_count_low   == 0x69 &&
578 		  fis->byte_count_high  == 0x96 &&
579 		  (fis->device & ~0x10) == 0))
580 
581 		/* Treat it as a superset? */
582 		dev->sata_dev.command_set = ATAPI_COMMAND_SET;
583 }
584 
585 /**
586  * sas_issue_ata_cmd -- Basic SATA command processing for discovery
587  * @dev: the device to send the command to
588  * @command: the command register
589  * @features: the features register
590  * @buffer: pointer to buffer to do I/O
591  * @size: size of @buffer
592  * @dma_dir: DMA direction.  DMA_xxx
593  */
594 static int sas_issue_ata_cmd(struct domain_device *dev, u8 command,
595 			     u8 features, void *buffer, int size,
596 			     enum dma_data_direction dma_dir)
597 {
598 	int res = 0;
599 	struct sas_task *task;
600 	struct dev_to_host_fis *d2h_fis = (struct dev_to_host_fis *)
601 		&dev->frame_rcvd[0];
602 
603 	res = -ENOMEM;
604 	task = sas_alloc_task(GFP_KERNEL);
605 	if (!task)
606 		goto out;
607 
608 	task->dev = dev;
609 
610 	task->ata_task.fis.fis_type = 0x27;
611 	task->ata_task.fis.command = command;
612 	task->ata_task.fis.features = features;
613 	task->ata_task.fis.device = d2h_fis->device;
614 	task->ata_task.retry_count = 1;
615 
616 	res = sas_execute_task(task, buffer, size, dma_dir);
617 
618 	sas_free_task(task);
619 out:
620 	return res;
621 }
622 
623 #define ATA_IDENTIFY_DEV         0xEC
624 #define ATA_IDENTIFY_PACKET_DEV  0xA1
625 #define ATA_SET_FEATURES         0xEF
626 #define ATA_FEATURE_PUP_STBY_SPIN_UP 0x07
627 
628 /**
629  * sas_discover_sata_dev -- discover a STP/SATA device (SATA_DEV)
630  * @dev: STP/SATA device of interest (ATA/ATAPI)
631  *
632  * The LLDD has already been notified of this device, so that we can
633  * send FISes to it.  Here we try to get IDENTIFY DEVICE or IDENTIFY
634  * PACKET DEVICE, if ATAPI device, so that the LLDD can fine-tune its
635  * performance for this device.
636  */
637 static int sas_discover_sata_dev(struct domain_device *dev)
638 {
639 	int     res;
640 	__le16  *identify_x;
641 	u8      command;
642 
643 	identify_x = kzalloc(512, GFP_KERNEL);
644 	if (!identify_x)
645 		return -ENOMEM;
646 
647 	if (dev->sata_dev.command_set == ATA_COMMAND_SET) {
648 		dev->sata_dev.identify_device = identify_x;
649 		command = ATA_IDENTIFY_DEV;
650 	} else {
651 		dev->sata_dev.identify_packet_device = identify_x;
652 		command = ATA_IDENTIFY_PACKET_DEV;
653 	}
654 
655 	res = sas_issue_ata_cmd(dev, command, 0, identify_x, 512,
656 				DMA_FROM_DEVICE);
657 	if (res)
658 		goto out_err;
659 
660 	/* lives on the media? */
661 	if (le16_to_cpu(identify_x[0]) & 4) {
662 		/* incomplete response */
663 		SAS_DPRINTK("sending SET FEATURE/PUP_STBY_SPIN_UP to "
664 			    "dev %llx\n", SAS_ADDR(dev->sas_addr));
665 		if (!(identify_x[83] & cpu_to_le16(1<<6)))
666 			goto cont1;
667 		res = sas_issue_ata_cmd(dev, ATA_SET_FEATURES,
668 					ATA_FEATURE_PUP_STBY_SPIN_UP,
669 					NULL, 0, DMA_NONE);
670 		if (res)
671 			goto cont1;
672 
673 		schedule_timeout_interruptible(5*HZ); /* More time? */
674 		res = sas_issue_ata_cmd(dev, command, 0, identify_x, 512,
675 					DMA_FROM_DEVICE);
676 		if (res)
677 			goto out_err;
678 	}
679 cont1:
680 	/* XXX Hint: register this SATA device with SATL.
681 	   When this returns, dev->sata_dev->lu is alive and
682 	   present.
683 	sas_satl_register_dev(dev);
684 	*/
685 
686 	sas_fill_in_rphy(dev, dev->rphy);
687 
688 	return 0;
689 out_err:
690 	dev->sata_dev.identify_packet_device = NULL;
691 	dev->sata_dev.identify_device = NULL;
692 	kfree(identify_x);
693 	return res;
694 }
695 
696 static int sas_discover_sata_pm(struct domain_device *dev)
697 {
698 	return -ENODEV;
699 }
700 
701 /**
702  * sas_discover_sata -- discover an STP/SATA domain device
703  * @dev: pointer to struct domain_device of interest
704  *
705  * First we notify the LLDD of this device, so we can send frames to
706  * it.  Then depending on the type of device we call the appropriate
707  * discover functions.  Once device discover is done, we notify the
708  * LLDD so that it can fine-tune its parameters for the device, by
709  * removing it and then adding it.  That is, the second time around,
710  * the driver would have certain fields, that it is looking at, set.
711  * Finally we initialize the kobj so that the device can be added to
712  * the system at registration time.  Devices directly attached to a HA
713  * port, have no parents.  All other devices do, and should have their
714  * "parent" pointer set appropriately before calling this function.
715  */
716 int sas_discover_sata(struct domain_device *dev)
717 {
718 	int res;
719 
720 	sas_get_ata_command_set(dev);
721 
722 	res = sas_notify_lldd_dev_found(dev);
723 	if (res)
724 		return res;
725 
726 	switch (dev->dev_type) {
727 	case SATA_DEV:
728 		res = sas_discover_sata_dev(dev);
729 		break;
730 	case SATA_PM:
731 		res = sas_discover_sata_pm(dev);
732 		break;
733 	default:
734 		break;
735 	}
736 	sas_notify_lldd_dev_gone(dev);
737 	if (!res) {
738 		sas_notify_lldd_dev_found(dev);
739 		res = sas_rphy_add(dev->rphy);
740 	}
741 
742 	return res;
743 }
744 
745 void sas_ata_strategy_handler(struct Scsi_Host *shost)
746 {
747 	struct scsi_device *sdev;
748 
749 	shost_for_each_device(sdev, shost) {
750 		struct domain_device *ddev = sdev_to_domain_dev(sdev);
751 		struct ata_port *ap = ddev->sata_dev.ap;
752 
753 		if (!dev_is_sata(ddev))
754 			continue;
755 
756 		ata_port_printk(ap, KERN_DEBUG, "sas eh calling libata port error handler");
757 		ata_scsi_port_error_handler(shost, ap);
758 	}
759 }
760 
761 int sas_ata_timed_out(struct scsi_cmnd *cmd, struct sas_task *task,
762 		      enum blk_eh_timer_return *rtn)
763 {
764 	struct domain_device *ddev = cmd_to_domain_dev(cmd);
765 
766 	if (!dev_is_sata(ddev) || task)
767 		return 0;
768 
769 	/* we're a sata device with no task, so this must be a libata
770 	 * eh timeout.  Ideally should hook into libata timeout
771 	 * handling, but there's no point, it just wants to activate
772 	 * the eh thread */
773 	*rtn = BLK_EH_NOT_HANDLED;
774 	return 1;
775 }
776 
777 int sas_ata_eh(struct Scsi_Host *shost, struct list_head *work_q,
778 	       struct list_head *done_q)
779 {
780 	int rtn = 0;
781 	struct scsi_cmnd *cmd, *n;
782 	struct ata_port *ap;
783 
784 	do {
785 		LIST_HEAD(sata_q);
786 
787 		ap = NULL;
788 
789 		list_for_each_entry_safe(cmd, n, work_q, eh_entry) {
790 			struct domain_device *ddev = cmd_to_domain_dev(cmd);
791 
792 			if (!dev_is_sata(ddev) || TO_SAS_TASK(cmd))
793 				continue;
794 			if (ap && ap != ddev->sata_dev.ap)
795 				continue;
796 			ap = ddev->sata_dev.ap;
797 			rtn = 1;
798 			list_move(&cmd->eh_entry, &sata_q);
799 		}
800 
801 		if (!list_empty(&sata_q)) {
802 			ata_port_printk(ap, KERN_DEBUG, "sas eh calling libata cmd error handler\n");
803 			ata_scsi_cmd_error_handler(shost, ap, &sata_q);
804 			/*
805 			 * ata's error handler may leave the cmd on the list
806 			 * so make sure they don't remain on a stack list
807 			 * about to go out of scope.
808 			 *
809 			 * This looks strange, since the commands are
810 			 * now part of no list, but the next error
811 			 * action will be ata_port_error_handler()
812 			 * which takes no list and sweeps them up
813 			 * anyway from the ata tag array.
814 			 */
815 			while (!list_empty(&sata_q))
816 				list_del_init(sata_q.next);
817 		}
818 	} while (ap);
819 
820 	return rtn;
821 }
822