Add the rt linux 4.1.3-rt3 as base
[kvmfornfv.git] / kernel / drivers / scsi / aic94xx / aic94xx_task.c
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 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 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         /* STP tasks come from libata which has already mapped
78          * the SG list */
79         if (sas_protocol_ata(task->task_proto))
80                 num_sg = task->num_scatter;
81         else
82                 num_sg = pci_map_sg(asd_ha->pcidev, task->scatter,
83                                     task->num_scatter, task->data_dir);
84         if (num_sg == 0)
85                 return -ENOMEM;
86
87         if (num_sg > 3) {
88                 int i;
89
90                 ascb->sg_arr = asd_alloc_coherent(asd_ha,
91                                                   num_sg*sizeof(struct sg_el),
92                                                   gfp_flags);
93                 if (!ascb->sg_arr) {
94                         res = -ENOMEM;
95                         goto err_unmap;
96                 }
97                 for_each_sg(task->scatter, sc, num_sg, i) {
98                         struct sg_el *sg =
99                                 &((struct sg_el *)ascb->sg_arr->vaddr)[i];
100                         sg->bus_addr = cpu_to_le64((u64)sg_dma_address(sc));
101                         sg->size = cpu_to_le32((u32)sg_dma_len(sc));
102                         if (i == num_sg-1)
103                                 sg->flags |= ASD_SG_EL_LIST_EOL;
104                 }
105
106                 for_each_sg(task->scatter, sc, 2, i) {
107                         sg_arr[i].bus_addr =
108                                 cpu_to_le64((u64)sg_dma_address(sc));
109                         sg_arr[i].size = cpu_to_le32((u32)sg_dma_len(sc));
110                 }
111                 sg_arr[1].next_sg_offs = 2 * sizeof(*sg_arr);
112                 sg_arr[1].flags |= ASD_SG_EL_LIST_EOS;
113
114                 memset(&sg_arr[2], 0, sizeof(*sg_arr));
115                 sg_arr[2].bus_addr=cpu_to_le64((u64)ascb->sg_arr->dma_handle);
116         } else {
117                 int i;
118                 for_each_sg(task->scatter, sc, num_sg, i) {
119                         sg_arr[i].bus_addr =
120                                 cpu_to_le64((u64)sg_dma_address(sc));
121                         sg_arr[i].size = cpu_to_le32((u32)sg_dma_len(sc));
122                 }
123                 sg_arr[i-1].flags |= ASD_SG_EL_LIST_EOL;
124         }
125
126         return 0;
127 err_unmap:
128         if (sas_protocol_ata(task->task_proto))
129                 pci_unmap_sg(asd_ha->pcidev, task->scatter, task->num_scatter,
130                              task->data_dir);
131         return res;
132 }
133
134 static void asd_unmap_scatterlist(struct asd_ascb *ascb)
135 {
136         struct asd_ha_struct *asd_ha = ascb->ha;
137         struct sas_task *task = ascb->uldd_task;
138
139         if (task->data_dir == PCI_DMA_NONE)
140                 return;
141
142         if (task->num_scatter == 0) {
143                 dma_addr_t dma = (dma_addr_t)
144                        le64_to_cpu(ascb->scb->ssp_task.sg_element[0].bus_addr);
145                 pci_unmap_single(ascb->ha->pcidev, dma, task->total_xfer_len,
146                                  task->data_dir);
147                 return;
148         }
149
150         asd_free_coherent(asd_ha, ascb->sg_arr);
151         if (task->task_proto != SAS_PROTOCOL_STP)
152                 pci_unmap_sg(asd_ha->pcidev, task->scatter, task->num_scatter,
153                              task->data_dir);
154 }
155
156 /* ---------- Task complete tasklet ---------- */
157
158 static void asd_get_response_tasklet(struct asd_ascb *ascb,
159                                      struct done_list_struct *dl)
160 {
161         struct asd_ha_struct *asd_ha = ascb->ha;
162         struct sas_task *task = ascb->uldd_task;
163         struct task_status_struct *ts = &task->task_status;
164         unsigned long flags;
165         struct tc_resp_sb_struct {
166                 __le16 index_escb;
167                 u8     len_lsb;
168                 u8     flags;
169         } __attribute__ ((packed)) *resp_sb = (void *) dl->status_block;
170
171 /*      int  size   = ((resp_sb->flags & 7) << 8) | resp_sb->len_lsb; */
172         int  edb_id = ((resp_sb->flags & 0x70) >> 4)-1;
173         struct asd_ascb *escb;
174         struct asd_dma_tok *edb;
175         void *r;
176
177         spin_lock_irqsave(&asd_ha->seq.tc_index_lock, flags);
178         escb = asd_tc_index_find(&asd_ha->seq,
179                                  (int)le16_to_cpu(resp_sb->index_escb));
180         spin_unlock_irqrestore(&asd_ha->seq.tc_index_lock, flags);
181
182         if (!escb) {
183                 ASD_DPRINTK("Uh-oh! No escb for this dl?!\n");
184                 return;
185         }
186
187         ts->buf_valid_size = 0;
188         edb = asd_ha->seq.edb_arr[edb_id + escb->edb_index];
189         r = edb->vaddr;
190         if (task->task_proto == SAS_PROTOCOL_SSP) {
191                 struct ssp_response_iu *iu =
192                         r + 16 + sizeof(struct ssp_frame_hdr);
193
194                 ts->residual = le32_to_cpu(*(__le32 *)r);
195
196                 sas_ssp_task_response(&asd_ha->pcidev->dev, task, iu);
197         }  else {
198                 struct ata_task_resp *resp = (void *) &ts->buf[0];
199
200                 ts->residual = le32_to_cpu(*(__le32 *)r);
201
202                 if (SAS_STATUS_BUF_SIZE >= sizeof(*resp)) {
203                         resp->frame_len = le16_to_cpu(*(__le16 *)(r+6));
204                         memcpy(&resp->ending_fis[0], r+16, ATA_RESP_FIS_SIZE);
205                         ts->buf_valid_size = sizeof(*resp);
206                 }
207         }
208
209         asd_invalidate_edb(escb, edb_id);
210 }
211
212 static void asd_task_tasklet_complete(struct asd_ascb *ascb,
213                                       struct done_list_struct *dl)
214 {
215         struct sas_task *task = ascb->uldd_task;
216         struct task_status_struct *ts = &task->task_status;
217         unsigned long flags;
218         u8 opcode = dl->opcode;
219
220         asd_can_dequeue(ascb->ha, 1);
221
222 Again:
223         switch (opcode) {
224         case TC_NO_ERROR:
225                 ts->resp = SAS_TASK_COMPLETE;
226                 ts->stat = SAM_STAT_GOOD;
227                 break;
228         case TC_UNDERRUN:
229                 ts->resp = SAS_TASK_COMPLETE;
230                 ts->stat = SAS_DATA_UNDERRUN;
231                 ts->residual = le32_to_cpu(*(__le32 *)dl->status_block);
232                 break;
233         case TC_OVERRUN:
234                 ts->resp = SAS_TASK_COMPLETE;
235                 ts->stat = SAS_DATA_OVERRUN;
236                 ts->residual = 0;
237                 break;
238         case TC_SSP_RESP:
239         case TC_ATA_RESP:
240                 ts->resp = SAS_TASK_COMPLETE;
241                 ts->stat = SAS_PROTO_RESPONSE;
242                 asd_get_response_tasklet(ascb, dl);
243                 break;
244         case TF_OPEN_REJECT:
245                 ts->resp = SAS_TASK_UNDELIVERED;
246                 ts->stat = SAS_OPEN_REJECT;
247                 if (dl->status_block[1] & 2)
248                         ts->open_rej_reason = 1 + dl->status_block[2];
249                 else if (dl->status_block[1] & 1)
250                         ts->open_rej_reason = (dl->status_block[2] >> 4)+10;
251                 else
252                         ts->open_rej_reason = SAS_OREJ_UNKNOWN;
253                 break;
254         case TF_OPEN_TO:
255                 ts->resp = SAS_TASK_UNDELIVERED;
256                 ts->stat = SAS_OPEN_TO;
257                 break;
258         case TF_PHY_DOWN:
259         case TU_PHY_DOWN:
260                 ts->resp = SAS_TASK_UNDELIVERED;
261                 ts->stat = SAS_PHY_DOWN;
262                 break;
263         case TI_PHY_DOWN:
264                 ts->resp = SAS_TASK_COMPLETE;
265                 ts->stat = SAS_PHY_DOWN;
266                 break;
267         case TI_BREAK:
268         case TI_PROTO_ERR:
269         case TI_NAK:
270         case TI_ACK_NAK_TO:
271         case TF_SMP_XMIT_RCV_ERR:
272         case TC_ATA_R_ERR_RECV:
273                 ts->resp = SAS_TASK_COMPLETE;
274                 ts->stat = SAS_INTERRUPTED;
275                 break;
276         case TF_BREAK:
277         case TU_BREAK:
278         case TU_ACK_NAK_TO:
279         case TF_SMPRSP_TO:
280                 ts->resp = SAS_TASK_UNDELIVERED;
281                 ts->stat = SAS_DEV_NO_RESPONSE;
282                 break;
283         case TF_NAK_RECV:
284                 ts->resp = SAS_TASK_COMPLETE;
285                 ts->stat = SAS_NAK_R_ERR;
286                 break;
287         case TA_I_T_NEXUS_LOSS:
288                 opcode = dl->status_block[0];
289                 goto Again;
290                 break;
291         case TF_INV_CONN_HANDLE:
292                 ts->resp = SAS_TASK_UNDELIVERED;
293                 ts->stat = SAS_DEVICE_UNKNOWN;
294                 break;
295         case TF_REQUESTED_N_PENDING:
296                 ts->resp = SAS_TASK_UNDELIVERED;
297                 ts->stat = SAS_PENDING;
298                 break;
299         case TC_TASK_CLEARED:
300         case TA_ON_REQ:
301                 ts->resp = SAS_TASK_COMPLETE;
302                 ts->stat = SAS_ABORTED_TASK;
303                 break;
304
305         case TF_NO_SMP_CONN:
306         case TF_TMF_NO_CTX:
307         case TF_TMF_NO_TAG:
308         case TF_TMF_TAG_FREE:
309         case TF_TMF_TASK_DONE:
310         case TF_TMF_NO_CONN_HANDLE:
311         case TF_IRTT_TO:
312         case TF_IU_SHORT:
313         case TF_DATA_OFFS_ERR:
314                 ts->resp = SAS_TASK_UNDELIVERED;
315                 ts->stat = SAS_DEV_NO_RESPONSE;
316                 break;
317
318         case TC_LINK_ADM_RESP:
319         case TC_CONTROL_PHY:
320         case TC_RESUME:
321         case TC_PARTIAL_SG_LIST:
322         default:
323                 ASD_DPRINTK("%s: dl opcode: 0x%x?\n", __func__, opcode);
324                 break;
325         }
326
327         switch (task->task_proto) {
328         case SAS_PROTOCOL_SATA:
329         case SAS_PROTOCOL_STP:
330                 asd_unbuild_ata_ascb(ascb);
331                 break;
332         case SAS_PROTOCOL_SMP:
333                 asd_unbuild_smp_ascb(ascb);
334                 break;
335         case SAS_PROTOCOL_SSP:
336                 asd_unbuild_ssp_ascb(ascb);
337         default:
338                 break;
339         }
340
341         spin_lock_irqsave(&task->task_state_lock, flags);
342         task->task_state_flags &= ~SAS_TASK_STATE_PENDING;
343         task->task_state_flags &= ~SAS_TASK_AT_INITIATOR;
344         task->task_state_flags |= SAS_TASK_STATE_DONE;
345         if (unlikely((task->task_state_flags & SAS_TASK_STATE_ABORTED))) {
346                 struct completion *completion = ascb->completion;
347                 spin_unlock_irqrestore(&task->task_state_lock, flags);
348                 ASD_DPRINTK("task 0x%p done with opcode 0x%x resp 0x%x "
349                             "stat 0x%x but aborted by upper layer!\n",
350                             task, opcode, ts->resp, ts->stat);
351                 if (completion)
352                         complete(completion);
353         } else {
354                 spin_unlock_irqrestore(&task->task_state_lock, flags);
355                 task->lldd_task = NULL;
356                 asd_ascb_free(ascb);
357                 mb();
358                 task->task_done(task);
359         }
360 }
361
362 /* ---------- ATA ---------- */
363
364 static int asd_build_ata_ascb(struct asd_ascb *ascb, struct sas_task *task,
365                               gfp_t gfp_flags)
366 {
367         struct domain_device *dev = task->dev;
368         struct scb *scb;
369         u8     flags;
370         int    res = 0;
371
372         scb = ascb->scb;
373
374         if (unlikely(task->ata_task.device_control_reg_update))
375                 scb->header.opcode = CONTROL_ATA_DEV;
376         else if (dev->sata_dev.class == ATA_DEV_ATAPI)
377                 scb->header.opcode = INITIATE_ATAPI_TASK;
378         else
379                 scb->header.opcode = INITIATE_ATA_TASK;
380
381         scb->ata_task.proto_conn_rate = (1 << 5); /* STP */
382         if (dev->port->oob_mode == SAS_OOB_MODE)
383                 scb->ata_task.proto_conn_rate |= dev->linkrate;
384
385         scb->ata_task.total_xfer_len = cpu_to_le32(task->total_xfer_len);
386         scb->ata_task.fis = task->ata_task.fis;
387         if (likely(!task->ata_task.device_control_reg_update))
388                 scb->ata_task.fis.flags |= 0x80; /* C=1: update ATA cmd reg */
389         scb->ata_task.fis.flags &= 0xF0; /* PM_PORT field shall be 0 */
390         if (dev->sata_dev.class == ATA_DEV_ATAPI)
391                 memcpy(scb->ata_task.atapi_packet, task->ata_task.atapi_packet,
392                        16);
393         scb->ata_task.sister_scb = cpu_to_le16(0xFFFF);
394         scb->ata_task.conn_handle = cpu_to_le16(
395                 (u16)(unsigned long)dev->lldd_dev);
396
397         if (likely(!task->ata_task.device_control_reg_update)) {
398                 flags = 0;
399                 if (task->ata_task.dma_xfer)
400                         flags |= DATA_XFER_MODE_DMA;
401                 if (task->ata_task.use_ncq &&
402                     dev->sata_dev.class != ATA_DEV_ATAPI)
403                         flags |= ATA_Q_TYPE_NCQ;
404                 flags |= data_dir_flags[task->data_dir];
405                 scb->ata_task.ata_flags = flags;
406
407                 scb->ata_task.retry_count = task->ata_task.retry_count;
408
409                 flags = 0;
410                 if (task->ata_task.set_affil_pol)
411                         flags |= SET_AFFIL_POLICY;
412                 if (task->ata_task.stp_affil_pol)
413                         flags |= STP_AFFIL_POLICY;
414                 scb->ata_task.flags = flags;
415         }
416         ascb->tasklet_complete = asd_task_tasklet_complete;
417
418         if (likely(!task->ata_task.device_control_reg_update))
419                 res = asd_map_scatterlist(task, scb->ata_task.sg_element,
420                                           gfp_flags);
421
422         return res;
423 }
424
425 static void asd_unbuild_ata_ascb(struct asd_ascb *a)
426 {
427         asd_unmap_scatterlist(a);
428 }
429
430 /* ---------- SMP ---------- */
431
432 static int asd_build_smp_ascb(struct asd_ascb *ascb, struct sas_task *task,
433                               gfp_t gfp_flags)
434 {
435         struct asd_ha_struct *asd_ha = ascb->ha;
436         struct domain_device *dev = task->dev;
437         struct scb *scb;
438
439         pci_map_sg(asd_ha->pcidev, &task->smp_task.smp_req, 1,
440                    PCI_DMA_TODEVICE);
441         pci_map_sg(asd_ha->pcidev, &task->smp_task.smp_resp, 1,
442                    PCI_DMA_FROMDEVICE);
443
444         scb = ascb->scb;
445
446         scb->header.opcode = INITIATE_SMP_TASK;
447
448         scb->smp_task.proto_conn_rate = dev->linkrate;
449
450         scb->smp_task.smp_req.bus_addr =
451                 cpu_to_le64((u64)sg_dma_address(&task->smp_task.smp_req));
452         scb->smp_task.smp_req.size =
453                 cpu_to_le32((u32)sg_dma_len(&task->smp_task.smp_req)-4);
454
455         scb->smp_task.smp_resp.bus_addr =
456                 cpu_to_le64((u64)sg_dma_address(&task->smp_task.smp_resp));
457         scb->smp_task.smp_resp.size =
458                 cpu_to_le32((u32)sg_dma_len(&task->smp_task.smp_resp)-4);
459
460         scb->smp_task.sister_scb = cpu_to_le16(0xFFFF);
461         scb->smp_task.conn_handle = cpu_to_le16((u16)
462                                                 (unsigned long)dev->lldd_dev);
463
464         ascb->tasklet_complete = asd_task_tasklet_complete;
465
466         return 0;
467 }
468
469 static void asd_unbuild_smp_ascb(struct asd_ascb *a)
470 {
471         struct sas_task *task = a->uldd_task;
472
473         BUG_ON(!task);
474         pci_unmap_sg(a->ha->pcidev, &task->smp_task.smp_req, 1,
475                      PCI_DMA_TODEVICE);
476         pci_unmap_sg(a->ha->pcidev, &task->smp_task.smp_resp, 1,
477                      PCI_DMA_FROMDEVICE);
478 }
479
480 /* ---------- SSP ---------- */
481
482 static int asd_build_ssp_ascb(struct asd_ascb *ascb, struct sas_task *task,
483                               gfp_t gfp_flags)
484 {
485         struct domain_device *dev = task->dev;
486         struct scb *scb;
487         int    res = 0;
488
489         scb = ascb->scb;
490
491         scb->header.opcode = INITIATE_SSP_TASK;
492
493         scb->ssp_task.proto_conn_rate  = (1 << 4); /* SSP */
494         scb->ssp_task.proto_conn_rate |= dev->linkrate;
495         scb->ssp_task.total_xfer_len = cpu_to_le32(task->total_xfer_len);
496         scb->ssp_task.ssp_frame.frame_type = SSP_DATA;
497         memcpy(scb->ssp_task.ssp_frame.hashed_dest_addr, dev->hashed_sas_addr,
498                HASHED_SAS_ADDR_SIZE);
499         memcpy(scb->ssp_task.ssp_frame.hashed_src_addr,
500                dev->port->ha->hashed_sas_addr, HASHED_SAS_ADDR_SIZE);
501         scb->ssp_task.ssp_frame.tptt = cpu_to_be16(0xFFFF);
502
503         memcpy(scb->ssp_task.ssp_cmd.lun, task->ssp_task.LUN, 8);
504         if (task->ssp_task.enable_first_burst)
505                 scb->ssp_task.ssp_cmd.efb_prio_attr |= EFB_MASK;
506         scb->ssp_task.ssp_cmd.efb_prio_attr |= (task->ssp_task.task_prio << 3);
507         scb->ssp_task.ssp_cmd.efb_prio_attr |= (task->ssp_task.task_attr & 7);
508         memcpy(scb->ssp_task.ssp_cmd.cdb, task->ssp_task.cmd->cmnd,
509                task->ssp_task.cmd->cmd_len);
510
511         scb->ssp_task.sister_scb = cpu_to_le16(0xFFFF);
512         scb->ssp_task.conn_handle = cpu_to_le16(
513                 (u16)(unsigned long)dev->lldd_dev);
514         scb->ssp_task.data_dir = data_dir_flags[task->data_dir];
515         scb->ssp_task.retry_count = scb->ssp_task.retry_count;
516
517         ascb->tasklet_complete = asd_task_tasklet_complete;
518
519         res = asd_map_scatterlist(task, scb->ssp_task.sg_element, gfp_flags);
520
521         return res;
522 }
523
524 static void asd_unbuild_ssp_ascb(struct asd_ascb *a)
525 {
526         asd_unmap_scatterlist(a);
527 }
528
529 /* ---------- Execute Task ---------- */
530
531 static int asd_can_queue(struct asd_ha_struct *asd_ha, int num)
532 {
533         int res = 0;
534         unsigned long flags;
535
536         spin_lock_irqsave(&asd_ha->seq.pend_q_lock, flags);
537         if ((asd_ha->seq.can_queue - num) < 0)
538                 res = -SAS_QUEUE_FULL;
539         else
540                 asd_ha->seq.can_queue -= num;
541         spin_unlock_irqrestore(&asd_ha->seq.pend_q_lock, flags);
542
543         return res;
544 }
545
546 int asd_execute_task(struct sas_task *task, gfp_t gfp_flags)
547 {
548         int res = 0;
549         LIST_HEAD(alist);
550         struct sas_task *t = task;
551         struct asd_ascb *ascb = NULL, *a;
552         struct asd_ha_struct *asd_ha = task->dev->port->ha->lldd_ha;
553         unsigned long flags;
554
555         res = asd_can_queue(asd_ha, 1);
556         if (res)
557                 return res;
558
559         res = 1;
560         ascb = asd_ascb_alloc_list(asd_ha, &res, gfp_flags);
561         if (res) {
562                 res = -ENOMEM;
563                 goto out_err;
564         }
565
566         __list_add(&alist, ascb->list.prev, &ascb->list);
567         list_for_each_entry(a, &alist, list) {
568                 a->uldd_task = t;
569                 t->lldd_task = a;
570                 break;
571         }
572         list_for_each_entry(a, &alist, list) {
573                 t = a->uldd_task;
574                 a->uldd_timer = 1;
575                 if (t->task_proto & SAS_PROTOCOL_STP)
576                         t->task_proto = SAS_PROTOCOL_STP;
577                 switch (t->task_proto) {
578                 case SAS_PROTOCOL_SATA:
579                 case SAS_PROTOCOL_STP:
580                         res = asd_build_ata_ascb(a, t, gfp_flags);
581                         break;
582                 case SAS_PROTOCOL_SMP:
583                         res = asd_build_smp_ascb(a, t, gfp_flags);
584                         break;
585                 case SAS_PROTOCOL_SSP:
586                         res = asd_build_ssp_ascb(a, t, gfp_flags);
587                         break;
588                 default:
589                         asd_printk("unknown sas_task proto: 0x%x\n",
590                                    t->task_proto);
591                         res = -ENOMEM;
592                         break;
593                 }
594                 if (res)
595                         goto out_err_unmap;
596
597                 spin_lock_irqsave(&t->task_state_lock, flags);
598                 t->task_state_flags |= SAS_TASK_AT_INITIATOR;
599                 spin_unlock_irqrestore(&t->task_state_lock, flags);
600         }
601         list_del_init(&alist);
602
603         res = asd_post_ascb_list(asd_ha, ascb, 1);
604         if (unlikely(res)) {
605                 a = NULL;
606                 __list_add(&alist, ascb->list.prev, &ascb->list);
607                 goto out_err_unmap;
608         }
609
610         return 0;
611 out_err_unmap:
612         {
613                 struct asd_ascb *b = a;
614                 list_for_each_entry(a, &alist, list) {
615                         if (a == b)
616                                 break;
617                         t = a->uldd_task;
618                         spin_lock_irqsave(&t->task_state_lock, flags);
619                         t->task_state_flags &= ~SAS_TASK_AT_INITIATOR;
620                         spin_unlock_irqrestore(&t->task_state_lock, flags);
621                         switch (t->task_proto) {
622                         case SAS_PROTOCOL_SATA:
623                         case SAS_PROTOCOL_STP:
624                                 asd_unbuild_ata_ascb(a);
625                                 break;
626                         case SAS_PROTOCOL_SMP:
627                                 asd_unbuild_smp_ascb(a);
628                                 break;
629                         case SAS_PROTOCOL_SSP:
630                                 asd_unbuild_ssp_ascb(a);
631                         default:
632                                 break;
633                         }
634                         t->lldd_task = NULL;
635                 }
636         }
637         list_del_init(&alist);
638 out_err:
639         if (ascb)
640                 asd_ascb_free_list(ascb);
641         asd_can_dequeue(asd_ha, 1);
642         return res;
643 }