1 /*
2  * Aic94xx SAS/SATA Tasks
3  *
4  * Copyright (C) 2005 Adaptec, Inc.  All rights reserved.
5  * Copyright (C) 2005 Luben Tuikov <luben_tuikov@adaptec.com>
6  *
7  * This file is licensed under GPLv2.
8  *
9  * This file is part of the aic94xx driver.
10  *
11  * The aic94xx driver is free software; you can redistribute it and/or
12  * modify it under the terms of the GNU General Public License as
13  * published by the Free Software Foundation; version 2 of the
14  * License.
15  *
16  * The aic94xx driver is distributed in the hope that it will be useful,
17  * but WITHOUT ANY WARRANTY; without even the implied warranty of
18  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
19  * General Public License for more details.
20  *
21  * You should have received a copy of the GNU General Public License
22  * along with the aic94xx driver; if not, write to the Free Software
23  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
24  *
25  */
26 
27 #include <linux/spinlock.h>
28 #include "aic94xx.h"
29 #include "aic94xx_sas.h"
30 #include "aic94xx_hwi.h"
31 
32 static void asd_unbuild_ata_ascb(struct asd_ascb *a);
33 static void asd_unbuild_smp_ascb(struct asd_ascb *a);
34 static void asd_unbuild_ssp_ascb(struct asd_ascb *a);
35 
36 static inline void asd_can_dequeue(struct asd_ha_struct *asd_ha, int num)
37 {
38 	unsigned long flags;
39 
40 	spin_lock_irqsave(&asd_ha->seq.pend_q_lock, flags);
41 	asd_ha->seq.can_queue += num;
42 	spin_unlock_irqrestore(&asd_ha->seq.pend_q_lock, flags);
43 }
44 
45 /* PCI_DMA_... to our direction translation.
46  */
47 static const u8 data_dir_flags[] = {
48 	[PCI_DMA_BIDIRECTIONAL] = DATA_DIR_BYRECIPIENT,	/* UNSPECIFIED */
49 	[PCI_DMA_TODEVICE]      = DATA_DIR_OUT, /* OUTBOUND */
50 	[PCI_DMA_FROMDEVICE]    = DATA_DIR_IN, /* INBOUND */
51 	[PCI_DMA_NONE]          = DATA_DIR_NONE, /* NO TRANSFER */
52 };
53 
54 static inline int asd_map_scatterlist(struct sas_task *task,
55 				      struct sg_el *sg_arr,
56 				      gfp_t gfp_flags)
57 {
58 	struct asd_ascb *ascb = task->lldd_task;
59 	struct asd_ha_struct *asd_ha = ascb->ha;
60 	struct scatterlist *sc;
61 	int num_sg, res;
62 
63 	if (task->data_dir == PCI_DMA_NONE)
64 		return 0;
65 
66 	if (task->num_scatter == 0) {
67 		void *p = task->scatter;
68 		dma_addr_t dma = pci_map_single(asd_ha->pcidev, p,
69 						task->total_xfer_len,
70 						task->data_dir);
71 		sg_arr[0].bus_addr = cpu_to_le64((u64)dma);
72 		sg_arr[0].size = cpu_to_le32(task->total_xfer_len);
73 		sg_arr[0].flags |= ASD_SG_EL_LIST_EOL;
74 		return 0;
75 	}
76 
77 	num_sg = pci_map_sg(asd_ha->pcidev, task->scatter, task->num_scatter,
78 			    task->data_dir);
79 	if (num_sg == 0)
80 		return -ENOMEM;
81 
82 	if (num_sg > 3) {
83 		int i;
84 
85 		ascb->sg_arr = asd_alloc_coherent(asd_ha,
86 						  num_sg*sizeof(struct sg_el),
87 						  gfp_flags);
88 		if (!ascb->sg_arr) {
89 			res = -ENOMEM;
90 			goto err_unmap;
91 		}
92 		for (sc = task->scatter, i = 0; i < num_sg; i++, sc++) {
93 			struct sg_el *sg =
94 				&((struct sg_el *)ascb->sg_arr->vaddr)[i];
95 			sg->bus_addr = cpu_to_le64((u64)sg_dma_address(sc));
96 			sg->size = cpu_to_le32((u32)sg_dma_len(sc));
97 			if (i == num_sg-1)
98 				sg->flags |= ASD_SG_EL_LIST_EOL;
99 		}
100 
101 		for (sc = task->scatter, i = 0; i < 2; i++, sc++) {
102 			sg_arr[i].bus_addr =
103 				cpu_to_le64((u64)sg_dma_address(sc));
104 			sg_arr[i].size = cpu_to_le32((u32)sg_dma_len(sc));
105 		}
106 		sg_arr[1].next_sg_offs = 2 * sizeof(*sg_arr);
107 		sg_arr[1].flags |= ASD_SG_EL_LIST_EOS;
108 
109 		memset(&sg_arr[2], 0, sizeof(*sg_arr));
110 		sg_arr[2].bus_addr=cpu_to_le64((u64)ascb->sg_arr->dma_handle);
111 	} else {
112 		int i;
113 		for (sc = task->scatter, i = 0; i < num_sg; i++, sc++) {
114 			sg_arr[i].bus_addr =
115 				cpu_to_le64((u64)sg_dma_address(sc));
116 			sg_arr[i].size = cpu_to_le32((u32)sg_dma_len(sc));
117 		}
118 		sg_arr[i-1].flags |= ASD_SG_EL_LIST_EOL;
119 	}
120 
121 	return 0;
122 err_unmap:
123 	pci_unmap_sg(asd_ha->pcidev, task->scatter, task->num_scatter,
124 		     task->data_dir);
125 	return res;
126 }
127 
128 static inline void asd_unmap_scatterlist(struct asd_ascb *ascb)
129 {
130 	struct asd_ha_struct *asd_ha = ascb->ha;
131 	struct sas_task *task = ascb->uldd_task;
132 
133 	if (task->data_dir == PCI_DMA_NONE)
134 		return;
135 
136 	if (task->num_scatter == 0) {
137 		dma_addr_t dma = (dma_addr_t)
138 		       le64_to_cpu(ascb->scb->ssp_task.sg_element[0].bus_addr);
139 		pci_unmap_single(ascb->ha->pcidev, dma, task->total_xfer_len,
140 				 task->data_dir);
141 		return;
142 	}
143 
144 	asd_free_coherent(asd_ha, ascb->sg_arr);
145 	pci_unmap_sg(asd_ha->pcidev, task->scatter, task->num_scatter,
146 		     task->data_dir);
147 }
148 
149 /* ---------- Task complete tasklet ---------- */
150 
151 static void asd_get_response_tasklet(struct asd_ascb *ascb,
152 				     struct done_list_struct *dl)
153 {
154 	struct asd_ha_struct *asd_ha = ascb->ha;
155 	struct sas_task *task = ascb->uldd_task;
156 	struct task_status_struct *ts = &task->task_status;
157 	unsigned long flags;
158 	struct tc_resp_sb_struct {
159 		__le16 index_escb;
160 		u8     len_lsb;
161 		u8     flags;
162 	} __attribute__ ((packed)) *resp_sb = (void *) dl->status_block;
163 
164 /* 	int  size   = ((resp_sb->flags & 7) << 8) | resp_sb->len_lsb; */
165 	int  edb_id = ((resp_sb->flags & 0x70) >> 4)-1;
166 	struct asd_ascb *escb;
167 	struct asd_dma_tok *edb;
168 	void *r;
169 
170 	spin_lock_irqsave(&asd_ha->seq.tc_index_lock, flags);
171 	escb = asd_tc_index_find(&asd_ha->seq,
172 				 (int)le16_to_cpu(resp_sb->index_escb));
173 	spin_unlock_irqrestore(&asd_ha->seq.tc_index_lock, flags);
174 
175 	if (!escb) {
176 		ASD_DPRINTK("Uh-oh! No escb for this dl?!\n");
177 		return;
178 	}
179 
180 	ts->buf_valid_size = 0;
181 	edb = asd_ha->seq.edb_arr[edb_id + escb->edb_index];
182 	r = edb->vaddr;
183 	if (task->task_proto == SAS_PROTO_SSP) {
184 		struct ssp_response_iu *iu =
185 			r + 16 + sizeof(struct ssp_frame_hdr);
186 
187 		ts->residual = le32_to_cpu(*(__le32 *)r);
188 		ts->resp = SAS_TASK_COMPLETE;
189 		if (iu->datapres == 0)
190 			ts->stat = iu->status;
191 		else if (iu->datapres == 1)
192 			ts->stat = iu->resp_data[3];
193 		else if (iu->datapres == 2) {
194 			ts->stat = SAM_CHECK_COND;
195 			ts->buf_valid_size = min((u32) SAS_STATUS_BUF_SIZE,
196 					 be32_to_cpu(iu->sense_data_len));
197 			memcpy(ts->buf, iu->sense_data, ts->buf_valid_size);
198 			if (iu->status != SAM_CHECK_COND) {
199 				ASD_DPRINTK("device %llx sent sense data, but "
200 					    "stat(0x%x) is not CHECK_CONDITION"
201 					    "\n",
202 					    SAS_ADDR(task->dev->sas_addr),
203 					    ts->stat);
204 			}
205 		}
206 	}  else {
207 		struct ata_task_resp *resp = (void *) &ts->buf[0];
208 
209 		ts->residual = le32_to_cpu(*(__le32 *)r);
210 
211 		if (SAS_STATUS_BUF_SIZE >= sizeof(*resp)) {
212 			resp->frame_len = le16_to_cpu(*(__le16 *)(r+6));
213 			memcpy(&resp->ending_fis[0], r+16, 24);
214 			ts->buf_valid_size = sizeof(*resp);
215 		}
216 	}
217 
218 	asd_invalidate_edb(escb, edb_id);
219 }
220 
221 static void asd_task_tasklet_complete(struct asd_ascb *ascb,
222 				      struct done_list_struct *dl)
223 {
224 	struct sas_task *task = ascb->uldd_task;
225 	struct task_status_struct *ts = &task->task_status;
226 	unsigned long flags;
227 	u8 opcode = dl->opcode;
228 
229 	asd_can_dequeue(ascb->ha, 1);
230 
231 Again:
232 	switch (opcode) {
233 	case TC_NO_ERROR:
234 		ts->resp = SAS_TASK_COMPLETE;
235 		ts->stat = SAM_GOOD;
236 		break;
237 	case TC_UNDERRUN:
238 		ts->resp = SAS_TASK_COMPLETE;
239 		ts->stat = SAS_DATA_UNDERRUN;
240 		ts->residual = le32_to_cpu(*(__le32 *)dl->status_block);
241 		break;
242 	case TC_OVERRUN:
243 		ts->resp = SAS_TASK_COMPLETE;
244 		ts->stat = SAS_DATA_OVERRUN;
245 		ts->residual = 0;
246 		break;
247 	case TC_SSP_RESP:
248 	case TC_ATA_RESP:
249 		ts->resp = SAS_TASK_COMPLETE;
250 		ts->stat = SAS_PROTO_RESPONSE;
251 		asd_get_response_tasklet(ascb, dl);
252 		break;
253 	case TF_OPEN_REJECT:
254 		ts->resp = SAS_TASK_UNDELIVERED;
255 		ts->stat = SAS_OPEN_REJECT;
256 		if (dl->status_block[1] & 2)
257 			ts->open_rej_reason = 1 + dl->status_block[2];
258 		else if (dl->status_block[1] & 1)
259 			ts->open_rej_reason = (dl->status_block[2] >> 4)+10;
260 		else
261 			ts->open_rej_reason = SAS_OREJ_UNKNOWN;
262 		break;
263 	case TF_OPEN_TO:
264 		ts->resp = SAS_TASK_UNDELIVERED;
265 		ts->stat = SAS_OPEN_TO;
266 		break;
267 	case TF_PHY_DOWN:
268 	case TU_PHY_DOWN:
269 		ts->resp = SAS_TASK_UNDELIVERED;
270 		ts->stat = SAS_PHY_DOWN;
271 		break;
272 	case TI_PHY_DOWN:
273 		ts->resp = SAS_TASK_COMPLETE;
274 		ts->stat = SAS_PHY_DOWN;
275 		break;
276 	case TI_BREAK:
277 	case TI_PROTO_ERR:
278 	case TI_NAK:
279 	case TI_ACK_NAK_TO:
280 	case TF_SMP_XMIT_RCV_ERR:
281 	case TC_ATA_R_ERR_RECV:
282 		ts->resp = SAS_TASK_COMPLETE;
283 		ts->stat = SAS_INTERRUPTED;
284 		break;
285 	case TF_BREAK:
286 	case TU_BREAK:
287 	case TU_ACK_NAK_TO:
288 	case TF_SMPRSP_TO:
289 		ts->resp = SAS_TASK_UNDELIVERED;
290 		ts->stat = SAS_DEV_NO_RESPONSE;
291 		break;
292 	case TF_NAK_RECV:
293 		ts->resp = SAS_TASK_COMPLETE;
294 		ts->stat = SAS_NAK_R_ERR;
295 		break;
296 	case TA_I_T_NEXUS_LOSS:
297 		opcode = dl->status_block[0];
298 		goto Again;
299 		break;
300 	case TF_INV_CONN_HANDLE:
301 		ts->resp = SAS_TASK_UNDELIVERED;
302 		ts->stat = SAS_DEVICE_UNKNOWN;
303 		break;
304 	case TF_REQUESTED_N_PENDING:
305 		ts->resp = SAS_TASK_UNDELIVERED;
306 		ts->stat = SAS_PENDING;
307 		break;
308 	case TC_TASK_CLEARED:
309 	case TA_ON_REQ:
310 		ts->resp = SAS_TASK_COMPLETE;
311 		ts->stat = SAS_ABORTED_TASK;
312 		break;
313 
314 	case TF_NO_SMP_CONN:
315 	case TF_TMF_NO_CTX:
316 	case TF_TMF_NO_TAG:
317 	case TF_TMF_TAG_FREE:
318 	case TF_TMF_TASK_DONE:
319 	case TF_TMF_NO_CONN_HANDLE:
320 	case TF_IRTT_TO:
321 	case TF_IU_SHORT:
322 	case TF_DATA_OFFS_ERR:
323 		ts->resp = SAS_TASK_UNDELIVERED;
324 		ts->stat = SAS_DEV_NO_RESPONSE;
325 		break;
326 
327 	case TC_LINK_ADM_RESP:
328 	case TC_CONTROL_PHY:
329 	case TC_RESUME:
330 	case TC_PARTIAL_SG_LIST:
331 	default:
332 		ASD_DPRINTK("%s: dl opcode: 0x%x?\n", __FUNCTION__, opcode);
333 		break;
334 	}
335 
336 	switch (task->task_proto) {
337 	case SATA_PROTO:
338 	case SAS_PROTO_STP:
339 		asd_unbuild_ata_ascb(ascb);
340 		break;
341 	case SAS_PROTO_SMP:
342 		asd_unbuild_smp_ascb(ascb);
343 		break;
344 	case SAS_PROTO_SSP:
345 		asd_unbuild_ssp_ascb(ascb);
346 	default:
347 		break;
348 	}
349 
350 	spin_lock_irqsave(&task->task_state_lock, flags);
351 	task->task_state_flags &= ~SAS_TASK_STATE_PENDING;
352 	task->task_state_flags &= ~SAS_TASK_AT_INITIATOR;
353 	task->task_state_flags |= SAS_TASK_STATE_DONE;
354 	if (unlikely((task->task_state_flags & SAS_TASK_STATE_ABORTED))) {
355 		spin_unlock_irqrestore(&task->task_state_lock, flags);
356 		ASD_DPRINTK("task 0x%p done with opcode 0x%x resp 0x%x "
357 			    "stat 0x%x but aborted by upper layer!\n",
358 			    task, opcode, ts->resp, ts->stat);
359 		complete(&ascb->completion);
360 	} else {
361 		spin_unlock_irqrestore(&task->task_state_lock, flags);
362 		task->lldd_task = NULL;
363 		asd_ascb_free(ascb);
364 		mb();
365 		task->task_done(task);
366 	}
367 }
368 
369 /* ---------- ATA ---------- */
370 
371 static int asd_build_ata_ascb(struct asd_ascb *ascb, struct sas_task *task,
372 			      gfp_t gfp_flags)
373 {
374 	struct domain_device *dev = task->dev;
375 	struct scb *scb;
376 	u8     flags;
377 	int    res = 0;
378 
379 	scb = ascb->scb;
380 
381 	if (unlikely(task->ata_task.device_control_reg_update))
382 		scb->header.opcode = CONTROL_ATA_DEV;
383 	else if (dev->sata_dev.command_set == ATA_COMMAND_SET)
384 		scb->header.opcode = INITIATE_ATA_TASK;
385 	else
386 		scb->header.opcode = INITIATE_ATAPI_TASK;
387 
388 	scb->ata_task.proto_conn_rate = (1 << 5); /* STP */
389 	if (dev->port->oob_mode == SAS_OOB_MODE)
390 		scb->ata_task.proto_conn_rate |= dev->linkrate;
391 
392 	scb->ata_task.total_xfer_len = cpu_to_le32(task->total_xfer_len);
393 	scb->ata_task.fis = task->ata_task.fis;
394 	scb->ata_task.fis.fis_type = 0x27;
395 	if (likely(!task->ata_task.device_control_reg_update))
396 		scb->ata_task.fis.flags |= 0x80; /* C=1: update ATA cmd reg */
397 	scb->ata_task.fis.flags &= 0xF0; /* PM_PORT field shall be 0 */
398 	if (dev->sata_dev.command_set == ATAPI_COMMAND_SET)
399 		memcpy(scb->ata_task.atapi_packet, task->ata_task.atapi_packet,
400 		       16);
401 	scb->ata_task.sister_scb = cpu_to_le16(0xFFFF);
402 	scb->ata_task.conn_handle = cpu_to_le16(
403 		(u16)(unsigned long)dev->lldd_dev);
404 
405 	if (likely(!task->ata_task.device_control_reg_update)) {
406 		flags = 0;
407 		if (task->ata_task.dma_xfer)
408 			flags |= DATA_XFER_MODE_DMA;
409 		if (task->ata_task.use_ncq &&
410 		    dev->sata_dev.command_set != ATAPI_COMMAND_SET)
411 			flags |= ATA_Q_TYPE_NCQ;
412 		flags |= data_dir_flags[task->data_dir];
413 		scb->ata_task.ata_flags = flags;
414 
415 		scb->ata_task.retry_count = task->ata_task.retry_count;
416 
417 		flags = 0;
418 		if (task->ata_task.set_affil_pol)
419 			flags |= SET_AFFIL_POLICY;
420 		if (task->ata_task.stp_affil_pol)
421 			flags |= STP_AFFIL_POLICY;
422 		scb->ata_task.flags = flags;
423 	}
424 	ascb->tasklet_complete = asd_task_tasklet_complete;
425 
426 	if (likely(!task->ata_task.device_control_reg_update))
427 		res = asd_map_scatterlist(task, scb->ata_task.sg_element,
428 					  gfp_flags);
429 
430 	return res;
431 }
432 
433 static void asd_unbuild_ata_ascb(struct asd_ascb *a)
434 {
435 	asd_unmap_scatterlist(a);
436 }
437 
438 /* ---------- SMP ---------- */
439 
440 static int asd_build_smp_ascb(struct asd_ascb *ascb, struct sas_task *task,
441 			      gfp_t gfp_flags)
442 {
443 	struct asd_ha_struct *asd_ha = ascb->ha;
444 	struct domain_device *dev = task->dev;
445 	struct scb *scb;
446 
447 	pci_map_sg(asd_ha->pcidev, &task->smp_task.smp_req, 1,
448 		   PCI_DMA_FROMDEVICE);
449 	pci_map_sg(asd_ha->pcidev, &task->smp_task.smp_resp, 1,
450 		   PCI_DMA_FROMDEVICE);
451 
452 	scb = ascb->scb;
453 
454 	scb->header.opcode = INITIATE_SMP_TASK;
455 
456 	scb->smp_task.proto_conn_rate = dev->linkrate;
457 
458 	scb->smp_task.smp_req.bus_addr =
459 		cpu_to_le64((u64)sg_dma_address(&task->smp_task.smp_req));
460 	scb->smp_task.smp_req.size =
461 		cpu_to_le32((u32)sg_dma_len(&task->smp_task.smp_req)-4);
462 
463 	scb->smp_task.smp_resp.bus_addr =
464 		cpu_to_le64((u64)sg_dma_address(&task->smp_task.smp_resp));
465 	scb->smp_task.smp_resp.size =
466 		cpu_to_le32((u32)sg_dma_len(&task->smp_task.smp_resp)-4);
467 
468 	scb->smp_task.sister_scb = cpu_to_le16(0xFFFF);
469 	scb->smp_task.conn_handle = cpu_to_le16((u16)
470 						(unsigned long)dev->lldd_dev);
471 
472 	ascb->tasklet_complete = asd_task_tasklet_complete;
473 
474 	return 0;
475 }
476 
477 static void asd_unbuild_smp_ascb(struct asd_ascb *a)
478 {
479 	struct sas_task *task = a->uldd_task;
480 
481 	BUG_ON(!task);
482 	pci_unmap_sg(a->ha->pcidev, &task->smp_task.smp_req, 1,
483 		     PCI_DMA_FROMDEVICE);
484 	pci_unmap_sg(a->ha->pcidev, &task->smp_task.smp_resp, 1,
485 		     PCI_DMA_FROMDEVICE);
486 }
487 
488 /* ---------- SSP ---------- */
489 
490 static int asd_build_ssp_ascb(struct asd_ascb *ascb, struct sas_task *task,
491 			      gfp_t gfp_flags)
492 {
493 	struct domain_device *dev = task->dev;
494 	struct scb *scb;
495 	int    res = 0;
496 
497 	scb = ascb->scb;
498 
499 	scb->header.opcode = INITIATE_SSP_TASK;
500 
501 	scb->ssp_task.proto_conn_rate  = (1 << 4); /* SSP */
502 	scb->ssp_task.proto_conn_rate |= dev->linkrate;
503 	scb->ssp_task.total_xfer_len = cpu_to_le32(task->total_xfer_len);
504 	scb->ssp_task.ssp_frame.frame_type = SSP_DATA;
505 	memcpy(scb->ssp_task.ssp_frame.hashed_dest_addr, dev->hashed_sas_addr,
506 	       HASHED_SAS_ADDR_SIZE);
507 	memcpy(scb->ssp_task.ssp_frame.hashed_src_addr,
508 	       dev->port->ha->hashed_sas_addr, HASHED_SAS_ADDR_SIZE);
509 	scb->ssp_task.ssp_frame.tptt = cpu_to_be16(0xFFFF);
510 
511 	memcpy(scb->ssp_task.ssp_cmd.lun, task->ssp_task.LUN, 8);
512 	if (task->ssp_task.enable_first_burst)
513 		scb->ssp_task.ssp_cmd.efb_prio_attr |= EFB_MASK;
514 	scb->ssp_task.ssp_cmd.efb_prio_attr |= (task->ssp_task.task_prio << 3);
515 	scb->ssp_task.ssp_cmd.efb_prio_attr |= (task->ssp_task.task_attr & 7);
516 	memcpy(scb->ssp_task.ssp_cmd.cdb, task->ssp_task.cdb, 16);
517 
518 	scb->ssp_task.sister_scb = cpu_to_le16(0xFFFF);
519 	scb->ssp_task.conn_handle = cpu_to_le16(
520 		(u16)(unsigned long)dev->lldd_dev);
521 	scb->ssp_task.data_dir = data_dir_flags[task->data_dir];
522 	scb->ssp_task.retry_count = scb->ssp_task.retry_count;
523 
524 	ascb->tasklet_complete = asd_task_tasklet_complete;
525 
526 	res = asd_map_scatterlist(task, scb->ssp_task.sg_element, gfp_flags);
527 
528 	return res;
529 }
530 
531 static void asd_unbuild_ssp_ascb(struct asd_ascb *a)
532 {
533 	asd_unmap_scatterlist(a);
534 }
535 
536 /* ---------- Execute Task ---------- */
537 
538 static inline int asd_can_queue(struct asd_ha_struct *asd_ha, int num)
539 {
540 	int res = 0;
541 	unsigned long flags;
542 
543 	spin_lock_irqsave(&asd_ha->seq.pend_q_lock, flags);
544 	if ((asd_ha->seq.can_queue - num) < 0)
545 		res = -SAS_QUEUE_FULL;
546 	else
547 		asd_ha->seq.can_queue -= num;
548 	spin_unlock_irqrestore(&asd_ha->seq.pend_q_lock, flags);
549 
550 	return res;
551 }
552 
553 int asd_execute_task(struct sas_task *task, const int num,
554 		     gfp_t gfp_flags)
555 {
556 	int res = 0;
557 	LIST_HEAD(alist);
558 	struct sas_task *t = task;
559 	struct asd_ascb *ascb = NULL, *a;
560 	struct asd_ha_struct *asd_ha = task->dev->port->ha->lldd_ha;
561 	unsigned long flags;
562 
563 	res = asd_can_queue(asd_ha, num);
564 	if (res)
565 		return res;
566 
567 	res = num;
568 	ascb = asd_ascb_alloc_list(asd_ha, &res, gfp_flags);
569 	if (res) {
570 		res = -ENOMEM;
571 		goto out_err;
572 	}
573 
574 	__list_add(&alist, ascb->list.prev, &ascb->list);
575 	list_for_each_entry(a, &alist, list) {
576 		a->uldd_task = t;
577 		t->lldd_task = a;
578 		t = list_entry(t->list.next, struct sas_task, list);
579 	}
580 	list_for_each_entry(a, &alist, list) {
581 		t = a->uldd_task;
582 		a->uldd_timer = 1;
583 		if (t->task_proto & SAS_PROTO_STP)
584 			t->task_proto = SAS_PROTO_STP;
585 		switch (t->task_proto) {
586 		case SATA_PROTO:
587 		case SAS_PROTO_STP:
588 			res = asd_build_ata_ascb(a, t, gfp_flags);
589 			break;
590 		case SAS_PROTO_SMP:
591 			res = asd_build_smp_ascb(a, t, gfp_flags);
592 			break;
593 		case SAS_PROTO_SSP:
594 			res = asd_build_ssp_ascb(a, t, gfp_flags);
595 			break;
596 		default:
597 			asd_printk("unknown sas_task proto: 0x%x\n",
598 				   t->task_proto);
599 			res = -ENOMEM;
600 			break;
601 		}
602 		if (res)
603 			goto out_err_unmap;
604 
605 		spin_lock_irqsave(&t->task_state_lock, flags);
606 		t->task_state_flags |= SAS_TASK_AT_INITIATOR;
607 		spin_unlock_irqrestore(&t->task_state_lock, flags);
608 	}
609 	list_del_init(&alist);
610 
611 	res = asd_post_ascb_list(asd_ha, ascb, num);
612 	if (unlikely(res)) {
613 		a = NULL;
614 		__list_add(&alist, ascb->list.prev, &ascb->list);
615 		goto out_err_unmap;
616 	}
617 
618 	return 0;
619 out_err_unmap:
620 	{
621 		struct asd_ascb *b = a;
622 		list_for_each_entry(a, &alist, list) {
623 			if (a == b)
624 				break;
625 			t = a->uldd_task;
626 			spin_lock_irqsave(&t->task_state_lock, flags);
627 			t->task_state_flags &= ~SAS_TASK_AT_INITIATOR;
628 			spin_unlock_irqrestore(&t->task_state_lock, flags);
629 			switch (t->task_proto) {
630 			case SATA_PROTO:
631 			case SAS_PROTO_STP:
632 				asd_unbuild_ata_ascb(a);
633 				break;
634 			case SAS_PROTO_SMP:
635 				asd_unbuild_smp_ascb(a);
636 				break;
637 			case SAS_PROTO_SSP:
638 				asd_unbuild_ssp_ascb(a);
639 			default:
640 				break;
641 			}
642 			t->lldd_task = NULL;
643 		}
644 	}
645 	list_del_init(&alist);
646 out_err:
647 	if (ascb)
648 		asd_ascb_free_list(ascb);
649 	asd_can_dequeue(asd_ha, num);
650 	return res;
651 }
652