linux/drivers/scsi/aic94xx/aic94xx_task.c
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   1// SPDX-License-Identifier: GPL-2.0-only
   2/*
   3 * Aic94xx SAS/SATA Tasks
   4 *
   5 * Copyright (C) 2005 Adaptec, Inc.  All rights reserved.
   6 * Copyright (C) 2005 Luben Tuikov <luben_tuikov@adaptec.com>
   7 */
   8
   9#include <linux/spinlock.h>
  10#include "aic94xx.h"
  11#include "aic94xx_sas.h"
  12#include "aic94xx_hwi.h"
  13
  14static void asd_unbuild_ata_ascb(struct asd_ascb *a);
  15static void asd_unbuild_smp_ascb(struct asd_ascb *a);
  16static void asd_unbuild_ssp_ascb(struct asd_ascb *a);
  17
  18static void asd_can_dequeue(struct asd_ha_struct *asd_ha, int num)
  19{
  20        unsigned long flags;
  21
  22        spin_lock_irqsave(&asd_ha->seq.pend_q_lock, flags);
  23        asd_ha->seq.can_queue += num;
  24        spin_unlock_irqrestore(&asd_ha->seq.pend_q_lock, flags);
  25}
  26
  27/* DMA_... to our direction translation.
  28 */
  29static const u8 data_dir_flags[] = {
  30        [DMA_BIDIRECTIONAL]     = DATA_DIR_BYRECIPIENT, /* UNSPECIFIED */
  31        [DMA_TO_DEVICE]         = DATA_DIR_OUT,         /* OUTBOUND */
  32        [DMA_FROM_DEVICE]       = DATA_DIR_IN,          /* INBOUND */
  33        [DMA_NONE]              = DATA_DIR_NONE,        /* NO TRANSFER */
  34};
  35
  36static int asd_map_scatterlist(struct sas_task *task,
  37                               struct sg_el *sg_arr,
  38                               gfp_t gfp_flags)
  39{
  40        struct asd_ascb *ascb = task->lldd_task;
  41        struct asd_ha_struct *asd_ha = ascb->ha;
  42        struct scatterlist *sc;
  43        int num_sg, res;
  44
  45        if (task->data_dir == DMA_NONE)
  46                return 0;
  47
  48        if (task->num_scatter == 0) {
  49                void *p = task->scatter;
  50                dma_addr_t dma = dma_map_single(&asd_ha->pcidev->dev, p,
  51                                                task->total_xfer_len,
  52                                                task->data_dir);
  53                sg_arr[0].bus_addr = cpu_to_le64((u64)dma);
  54                sg_arr[0].size = cpu_to_le32(task->total_xfer_len);
  55                sg_arr[0].flags |= ASD_SG_EL_LIST_EOL;
  56                return 0;
  57        }
  58
  59        /* STP tasks come from libata which has already mapped
  60         * the SG list */
  61        if (sas_protocol_ata(task->task_proto))
  62                num_sg = task->num_scatter;
  63        else
  64                num_sg = dma_map_sg(&asd_ha->pcidev->dev, task->scatter,
  65                                    task->num_scatter, task->data_dir);
  66        if (num_sg == 0)
  67                return -ENOMEM;
  68
  69        if (num_sg > 3) {
  70                int i;
  71
  72                ascb->sg_arr = asd_alloc_coherent(asd_ha,
  73                                                  num_sg*sizeof(struct sg_el),
  74                                                  gfp_flags);
  75                if (!ascb->sg_arr) {
  76                        res = -ENOMEM;
  77                        goto err_unmap;
  78                }
  79                for_each_sg(task->scatter, sc, num_sg, i) {
  80                        struct sg_el *sg =
  81                                &((struct sg_el *)ascb->sg_arr->vaddr)[i];
  82                        sg->bus_addr = cpu_to_le64((u64)sg_dma_address(sc));
  83                        sg->size = cpu_to_le32((u32)sg_dma_len(sc));
  84                        if (i == num_sg-1)
  85                                sg->flags |= ASD_SG_EL_LIST_EOL;
  86                }
  87
  88                for_each_sg(task->scatter, sc, 2, i) {
  89                        sg_arr[i].bus_addr =
  90                                cpu_to_le64((u64)sg_dma_address(sc));
  91                        sg_arr[i].size = cpu_to_le32((u32)sg_dma_len(sc));
  92                }
  93                sg_arr[1].next_sg_offs = 2 * sizeof(*sg_arr);
  94                sg_arr[1].flags |= ASD_SG_EL_LIST_EOS;
  95
  96                memset(&sg_arr[2], 0, sizeof(*sg_arr));
  97                sg_arr[2].bus_addr=cpu_to_le64((u64)ascb->sg_arr->dma_handle);
  98        } else {
  99                int i;
 100                for_each_sg(task->scatter, sc, num_sg, i) {
 101                        sg_arr[i].bus_addr =
 102                                cpu_to_le64((u64)sg_dma_address(sc));
 103                        sg_arr[i].size = cpu_to_le32((u32)sg_dma_len(sc));
 104                }
 105                sg_arr[i-1].flags |= ASD_SG_EL_LIST_EOL;
 106        }
 107
 108        return 0;
 109err_unmap:
 110        if (sas_protocol_ata(task->task_proto))
 111                dma_unmap_sg(&asd_ha->pcidev->dev, task->scatter,
 112                             task->num_scatter, task->data_dir);
 113        return res;
 114}
 115
 116static void asd_unmap_scatterlist(struct asd_ascb *ascb)
 117{
 118        struct asd_ha_struct *asd_ha = ascb->ha;
 119        struct sas_task *task = ascb->uldd_task;
 120
 121        if (task->data_dir == DMA_NONE)
 122                return;
 123
 124        if (task->num_scatter == 0) {
 125                dma_addr_t dma = (dma_addr_t)
 126                       le64_to_cpu(ascb->scb->ssp_task.sg_element[0].bus_addr);
 127                dma_unmap_single(&ascb->ha->pcidev->dev, dma,
 128                                 task->total_xfer_len, task->data_dir);
 129                return;
 130        }
 131
 132        asd_free_coherent(asd_ha, ascb->sg_arr);
 133        if (task->task_proto != SAS_PROTOCOL_STP)
 134                dma_unmap_sg(&asd_ha->pcidev->dev, task->scatter,
 135                             task->num_scatter, task->data_dir);
 136}
 137
 138/* ---------- Task complete tasklet ---------- */
 139
 140static void asd_get_response_tasklet(struct asd_ascb *ascb,
 141                                     struct done_list_struct *dl)
 142{
 143        struct asd_ha_struct *asd_ha = ascb->ha;
 144        struct sas_task *task = ascb->uldd_task;
 145        struct task_status_struct *ts = &task->task_status;
 146        unsigned long flags;
 147        struct tc_resp_sb_struct {
 148                __le16 index_escb;
 149                u8     len_lsb;
 150                u8     flags;
 151        } __attribute__ ((packed)) *resp_sb = (void *) dl->status_block;
 152
 153/*      int  size   = ((resp_sb->flags & 7) << 8) | resp_sb->len_lsb; */
 154        int  edb_id = ((resp_sb->flags & 0x70) >> 4)-1;
 155        struct asd_ascb *escb;
 156        struct asd_dma_tok *edb;
 157        void *r;
 158
 159        spin_lock_irqsave(&asd_ha->seq.tc_index_lock, flags);
 160        escb = asd_tc_index_find(&asd_ha->seq,
 161                                 (int)le16_to_cpu(resp_sb->index_escb));
 162        spin_unlock_irqrestore(&asd_ha->seq.tc_index_lock, flags);
 163
 164        if (!escb) {
 165                ASD_DPRINTK("Uh-oh! No escb for this dl?!\n");
 166                return;
 167        }
 168
 169        ts->buf_valid_size = 0;
 170        edb = asd_ha->seq.edb_arr[edb_id + escb->edb_index];
 171        r = edb->vaddr;
 172        if (task->task_proto == SAS_PROTOCOL_SSP) {
 173                struct ssp_response_iu *iu =
 174                        r + 16 + sizeof(struct ssp_frame_hdr);
 175
 176                ts->residual = le32_to_cpu(*(__le32 *)r);
 177
 178                sas_ssp_task_response(&asd_ha->pcidev->dev, task, iu);
 179        }  else {
 180                struct ata_task_resp *resp = (void *) &ts->buf[0];
 181
 182                ts->residual = le32_to_cpu(*(__le32 *)r);
 183
 184                if (SAS_STATUS_BUF_SIZE >= sizeof(*resp)) {
 185                        resp->frame_len = le16_to_cpu(*(__le16 *)(r+6));
 186                        memcpy(&resp->ending_fis[0], r+16, ATA_RESP_FIS_SIZE);
 187                        ts->buf_valid_size = sizeof(*resp);
 188                }
 189        }
 190
 191        asd_invalidate_edb(escb, edb_id);
 192}
 193
 194static void asd_task_tasklet_complete(struct asd_ascb *ascb,
 195                                      struct done_list_struct *dl)
 196{
 197        struct sas_task *task = ascb->uldd_task;
 198        struct task_status_struct *ts = &task->task_status;
 199        unsigned long flags;
 200        u8 opcode = dl->opcode;
 201
 202        asd_can_dequeue(ascb->ha, 1);
 203
 204Again:
 205        switch (opcode) {
 206        case TC_NO_ERROR:
 207                ts->resp = SAS_TASK_COMPLETE;
 208                ts->stat = SAS_SAM_STAT_GOOD;
 209                break;
 210        case TC_UNDERRUN:
 211                ts->resp = SAS_TASK_COMPLETE;
 212                ts->stat = SAS_DATA_UNDERRUN;
 213                ts->residual = le32_to_cpu(*(__le32 *)dl->status_block);
 214                break;
 215        case TC_OVERRUN:
 216                ts->resp = SAS_TASK_COMPLETE;
 217                ts->stat = SAS_DATA_OVERRUN;
 218                ts->residual = 0;
 219                break;
 220        case TC_SSP_RESP:
 221        case TC_ATA_RESP:
 222                ts->resp = SAS_TASK_COMPLETE;
 223                ts->stat = SAS_PROTO_RESPONSE;
 224                asd_get_response_tasklet(ascb, dl);
 225                break;
 226        case TF_OPEN_REJECT:
 227                ts->resp = SAS_TASK_UNDELIVERED;
 228                ts->stat = SAS_OPEN_REJECT;
 229                if (dl->status_block[1] & 2)
 230                        ts->open_rej_reason = 1 + dl->status_block[2];
 231                else if (dl->status_block[1] & 1)
 232                        ts->open_rej_reason = (dl->status_block[2] >> 4)+10;
 233                else
 234                        ts->open_rej_reason = SAS_OREJ_UNKNOWN;
 235                break;
 236        case TF_OPEN_TO:
 237                ts->resp = SAS_TASK_UNDELIVERED;
 238                ts->stat = SAS_OPEN_TO;
 239                break;
 240        case TF_PHY_DOWN:
 241        case TU_PHY_DOWN:
 242                ts->resp = SAS_TASK_UNDELIVERED;
 243                ts->stat = SAS_PHY_DOWN;
 244                break;
 245        case TI_PHY_DOWN:
 246                ts->resp = SAS_TASK_COMPLETE;
 247                ts->stat = SAS_PHY_DOWN;
 248                break;
 249        case TI_BREAK:
 250        case TI_PROTO_ERR:
 251        case TI_NAK:
 252        case TI_ACK_NAK_TO:
 253        case TF_SMP_XMIT_RCV_ERR:
 254        case TC_ATA_R_ERR_RECV:
 255                ts->resp = SAS_TASK_COMPLETE;
 256                ts->stat = SAS_INTERRUPTED;
 257                break;
 258        case TF_BREAK:
 259        case TU_BREAK:
 260        case TU_ACK_NAK_TO:
 261        case TF_SMPRSP_TO:
 262                ts->resp = SAS_TASK_UNDELIVERED;
 263                ts->stat = SAS_DEV_NO_RESPONSE;
 264                break;
 265        case TF_NAK_RECV:
 266                ts->resp = SAS_TASK_COMPLETE;
 267                ts->stat = SAS_NAK_R_ERR;
 268                break;
 269        case TA_I_T_NEXUS_LOSS:
 270                opcode = dl->status_block[0];
 271                goto Again;
 272        case TF_INV_CONN_HANDLE:
 273                ts->resp = SAS_TASK_UNDELIVERED;
 274                ts->stat = SAS_DEVICE_UNKNOWN;
 275                break;
 276        case TF_REQUESTED_N_PENDING:
 277                ts->resp = SAS_TASK_UNDELIVERED;
 278                ts->stat = SAS_PENDING;
 279                break;
 280        case TC_TASK_CLEARED:
 281        case TA_ON_REQ:
 282                ts->resp = SAS_TASK_COMPLETE;
 283                ts->stat = SAS_ABORTED_TASK;
 284                break;
 285
 286        case TF_NO_SMP_CONN:
 287        case TF_TMF_NO_CTX:
 288        case TF_TMF_NO_TAG:
 289        case TF_TMF_TAG_FREE:
 290        case TF_TMF_TASK_DONE:
 291        case TF_TMF_NO_CONN_HANDLE:
 292        case TF_IRTT_TO:
 293        case TF_IU_SHORT:
 294        case TF_DATA_OFFS_ERR:
 295                ts->resp = SAS_TASK_UNDELIVERED;
 296                ts->stat = SAS_DEV_NO_RESPONSE;
 297                break;
 298
 299        case TC_LINK_ADM_RESP:
 300        case TC_CONTROL_PHY:
 301        case TC_RESUME:
 302        case TC_PARTIAL_SG_LIST:
 303        default:
 304                ASD_DPRINTK("%s: dl opcode: 0x%x?\n", __func__, opcode);
 305                break;
 306        }
 307
 308        switch (task->task_proto) {
 309        case SAS_PROTOCOL_SATA:
 310        case SAS_PROTOCOL_STP:
 311                asd_unbuild_ata_ascb(ascb);
 312                break;
 313        case SAS_PROTOCOL_SMP:
 314                asd_unbuild_smp_ascb(ascb);
 315                break;
 316        case SAS_PROTOCOL_SSP:
 317                asd_unbuild_ssp_ascb(ascb);
 318                break;
 319        default:
 320                break;
 321        }
 322
 323        spin_lock_irqsave(&task->task_state_lock, flags);
 324        task->task_state_flags &= ~SAS_TASK_STATE_PENDING;
 325        task->task_state_flags |= SAS_TASK_STATE_DONE;
 326        if (unlikely((task->task_state_flags & SAS_TASK_STATE_ABORTED))) {
 327                struct completion *completion = ascb->completion;
 328                spin_unlock_irqrestore(&task->task_state_lock, flags);
 329                ASD_DPRINTK("task 0x%p done with opcode 0x%x resp 0x%x "
 330                            "stat 0x%x but aborted by upper layer!\n",
 331                            task, opcode, ts->resp, ts->stat);
 332                if (completion)
 333                        complete(completion);
 334        } else {
 335                spin_unlock_irqrestore(&task->task_state_lock, flags);
 336                task->lldd_task = NULL;
 337                asd_ascb_free(ascb);
 338                mb();
 339                task->task_done(task);
 340        }
 341}
 342
 343/* ---------- ATA ---------- */
 344
 345static int asd_build_ata_ascb(struct asd_ascb *ascb, struct sas_task *task,
 346                              gfp_t gfp_flags)
 347{
 348        struct domain_device *dev = task->dev;
 349        struct scb *scb;
 350        u8     flags;
 351        int    res = 0;
 352
 353        scb = ascb->scb;
 354
 355        if (unlikely(task->ata_task.device_control_reg_update))
 356                scb->header.opcode = CONTROL_ATA_DEV;
 357        else if (dev->sata_dev.class == ATA_DEV_ATAPI)
 358                scb->header.opcode = INITIATE_ATAPI_TASK;
 359        else
 360                scb->header.opcode = INITIATE_ATA_TASK;
 361
 362        scb->ata_task.proto_conn_rate = (1 << 5); /* STP */
 363        if (dev->port->oob_mode == SAS_OOB_MODE)
 364                scb->ata_task.proto_conn_rate |= dev->linkrate;
 365
 366        scb->ata_task.total_xfer_len = cpu_to_le32(task->total_xfer_len);
 367        scb->ata_task.fis = task->ata_task.fis;
 368        if (likely(!task->ata_task.device_control_reg_update))
 369                scb->ata_task.fis.flags |= 0x80; /* C=1: update ATA cmd reg */
 370        scb->ata_task.fis.flags &= 0xF0; /* PM_PORT field shall be 0 */
 371        if (dev->sata_dev.class == ATA_DEV_ATAPI)
 372                memcpy(scb->ata_task.atapi_packet, task->ata_task.atapi_packet,
 373                       16);
 374        scb->ata_task.sister_scb = cpu_to_le16(0xFFFF);
 375        scb->ata_task.conn_handle = cpu_to_le16(
 376                (u16)(unsigned long)dev->lldd_dev);
 377
 378        if (likely(!task->ata_task.device_control_reg_update)) {
 379                flags = 0;
 380                if (task->ata_task.dma_xfer)
 381                        flags |= DATA_XFER_MODE_DMA;
 382                if (task->ata_task.use_ncq &&
 383                    dev->sata_dev.class != ATA_DEV_ATAPI)
 384                        flags |= ATA_Q_TYPE_NCQ;
 385                flags |= data_dir_flags[task->data_dir];
 386                scb->ata_task.ata_flags = flags;
 387
 388                scb->ata_task.retry_count = task->ata_task.retry_count;
 389
 390                flags = 0;
 391                if (task->ata_task.set_affil_pol)
 392                        flags |= SET_AFFIL_POLICY;
 393                if (task->ata_task.stp_affil_pol)
 394                        flags |= STP_AFFIL_POLICY;
 395                scb->ata_task.flags = flags;
 396        }
 397        ascb->tasklet_complete = asd_task_tasklet_complete;
 398
 399        if (likely(!task->ata_task.device_control_reg_update))
 400                res = asd_map_scatterlist(task, scb->ata_task.sg_element,
 401                                          gfp_flags);
 402
 403        return res;
 404}
 405
 406static void asd_unbuild_ata_ascb(struct asd_ascb *a)
 407{
 408        asd_unmap_scatterlist(a);
 409}
 410
 411/* ---------- SMP ---------- */
 412
 413static int asd_build_smp_ascb(struct asd_ascb *ascb, struct sas_task *task,
 414                              gfp_t gfp_flags)
 415{
 416        struct asd_ha_struct *asd_ha = ascb->ha;
 417        struct domain_device *dev = task->dev;
 418        struct scb *scb;
 419
 420        dma_map_sg(&asd_ha->pcidev->dev, &task->smp_task.smp_req, 1,
 421                   DMA_TO_DEVICE);
 422        dma_map_sg(&asd_ha->pcidev->dev, &task->smp_task.smp_resp, 1,
 423                   DMA_FROM_DEVICE);
 424
 425        scb = ascb->scb;
 426
 427        scb->header.opcode = INITIATE_SMP_TASK;
 428
 429        scb->smp_task.proto_conn_rate = dev->linkrate;
 430
 431        scb->smp_task.smp_req.bus_addr =
 432                cpu_to_le64((u64)sg_dma_address(&task->smp_task.smp_req));
 433        scb->smp_task.smp_req.size =
 434                cpu_to_le32((u32)sg_dma_len(&task->smp_task.smp_req)-4);
 435
 436        scb->smp_task.smp_resp.bus_addr =
 437                cpu_to_le64((u64)sg_dma_address(&task->smp_task.smp_resp));
 438        scb->smp_task.smp_resp.size =
 439                cpu_to_le32((u32)sg_dma_len(&task->smp_task.smp_resp)-4);
 440
 441        scb->smp_task.sister_scb = cpu_to_le16(0xFFFF);
 442        scb->smp_task.conn_handle = cpu_to_le16((u16)
 443                                                (unsigned long)dev->lldd_dev);
 444
 445        ascb->tasklet_complete = asd_task_tasklet_complete;
 446
 447        return 0;
 448}
 449
 450static void asd_unbuild_smp_ascb(struct asd_ascb *a)
 451{
 452        struct sas_task *task = a->uldd_task;
 453
 454        BUG_ON(!task);
 455        dma_unmap_sg(&a->ha->pcidev->dev, &task->smp_task.smp_req, 1,
 456                     DMA_TO_DEVICE);
 457        dma_unmap_sg(&a->ha->pcidev->dev, &task->smp_task.smp_resp, 1,
 458                     DMA_FROM_DEVICE);
 459}
 460
 461/* ---------- SSP ---------- */
 462
 463static int asd_build_ssp_ascb(struct asd_ascb *ascb, struct sas_task *task,
 464                              gfp_t gfp_flags)
 465{
 466        struct domain_device *dev = task->dev;
 467        struct scb *scb;
 468        int    res = 0;
 469
 470        scb = ascb->scb;
 471
 472        scb->header.opcode = INITIATE_SSP_TASK;
 473
 474        scb->ssp_task.proto_conn_rate  = (1 << 4); /* SSP */
 475        scb->ssp_task.proto_conn_rate |= dev->linkrate;
 476        scb->ssp_task.total_xfer_len = cpu_to_le32(task->total_xfer_len);
 477        scb->ssp_task.ssp_frame.frame_type = SSP_DATA;
 478        memcpy(scb->ssp_task.ssp_frame.hashed_dest_addr, dev->hashed_sas_addr,
 479               HASHED_SAS_ADDR_SIZE);
 480        memcpy(scb->ssp_task.ssp_frame.hashed_src_addr,
 481               dev->port->ha->hashed_sas_addr, HASHED_SAS_ADDR_SIZE);
 482        scb->ssp_task.ssp_frame.tptt = cpu_to_be16(0xFFFF);
 483
 484        memcpy(scb->ssp_task.ssp_cmd.lun, task->ssp_task.LUN, 8);
 485        if (task->ssp_task.enable_first_burst)
 486                scb->ssp_task.ssp_cmd.efb_prio_attr |= EFB_MASK;
 487        scb->ssp_task.ssp_cmd.efb_prio_attr |= (task->ssp_task.task_prio << 3);
 488        scb->ssp_task.ssp_cmd.efb_prio_attr |= (task->ssp_task.task_attr & 7);
 489        memcpy(scb->ssp_task.ssp_cmd.cdb, task->ssp_task.cmd->cmnd,
 490               task->ssp_task.cmd->cmd_len);
 491
 492        scb->ssp_task.sister_scb = cpu_to_le16(0xFFFF);
 493        scb->ssp_task.conn_handle = cpu_to_le16(
 494                (u16)(unsigned long)dev->lldd_dev);
 495        scb->ssp_task.data_dir = data_dir_flags[task->data_dir];
 496        scb->ssp_task.retry_count = scb->ssp_task.retry_count;
 497
 498        ascb->tasklet_complete = asd_task_tasklet_complete;
 499
 500        res = asd_map_scatterlist(task, scb->ssp_task.sg_element, gfp_flags);
 501
 502        return res;
 503}
 504
 505static void asd_unbuild_ssp_ascb(struct asd_ascb *a)
 506{
 507        asd_unmap_scatterlist(a);
 508}
 509
 510/* ---------- Execute Task ---------- */
 511
 512static int asd_can_queue(struct asd_ha_struct *asd_ha, int num)
 513{
 514        int res = 0;
 515        unsigned long flags;
 516
 517        spin_lock_irqsave(&asd_ha->seq.pend_q_lock, flags);
 518        if ((asd_ha->seq.can_queue - num) < 0)
 519                res = -SAS_QUEUE_FULL;
 520        else
 521                asd_ha->seq.can_queue -= num;
 522        spin_unlock_irqrestore(&asd_ha->seq.pend_q_lock, flags);
 523
 524        return res;
 525}
 526
 527int asd_execute_task(struct sas_task *task, gfp_t gfp_flags)
 528{
 529        int res = 0;
 530        LIST_HEAD(alist);
 531        struct sas_task *t = task;
 532        struct asd_ascb *ascb = NULL, *a;
 533        struct asd_ha_struct *asd_ha = task->dev->port->ha->lldd_ha;
 534
 535        res = asd_can_queue(asd_ha, 1);
 536        if (res)
 537                return res;
 538
 539        res = 1;
 540        ascb = asd_ascb_alloc_list(asd_ha, &res, gfp_flags);
 541        if (res) {
 542                res = -ENOMEM;
 543                goto out_err;
 544        }
 545
 546        __list_add(&alist, ascb->list.prev, &ascb->list);
 547        list_for_each_entry(a, &alist, list) {
 548                a->uldd_task = t;
 549                t->lldd_task = a;
 550                break;
 551        }
 552        list_for_each_entry(a, &alist, list) {
 553                t = a->uldd_task;
 554                a->uldd_timer = 1;
 555                if (t->task_proto & SAS_PROTOCOL_STP)
 556                        t->task_proto = SAS_PROTOCOL_STP;
 557                switch (t->task_proto) {
 558                case SAS_PROTOCOL_SATA:
 559                case SAS_PROTOCOL_STP:
 560                        res = asd_build_ata_ascb(a, t, gfp_flags);
 561                        break;
 562                case SAS_PROTOCOL_SMP:
 563                        res = asd_build_smp_ascb(a, t, gfp_flags);
 564                        break;
 565                case SAS_PROTOCOL_SSP:
 566                        res = asd_build_ssp_ascb(a, t, gfp_flags);
 567                        break;
 568                default:
 569                        asd_printk("unknown sas_task proto: 0x%x\n",
 570                                   t->task_proto);
 571                        res = -ENOMEM;
 572                        break;
 573                }
 574                if (res)
 575                        goto out_err_unmap;
 576        }
 577        list_del_init(&alist);
 578
 579        res = asd_post_ascb_list(asd_ha, ascb, 1);
 580        if (unlikely(res)) {
 581                a = NULL;
 582                __list_add(&alist, ascb->list.prev, &ascb->list);
 583                goto out_err_unmap;
 584        }
 585
 586        return 0;
 587out_err_unmap:
 588        {
 589                struct asd_ascb *b = a;
 590                list_for_each_entry(a, &alist, list) {
 591                        if (a == b)
 592                                break;
 593                        t = a->uldd_task;
 594                        switch (t->task_proto) {
 595                        case SAS_PROTOCOL_SATA:
 596                        case SAS_PROTOCOL_STP:
 597                                asd_unbuild_ata_ascb(a);
 598                                break;
 599                        case SAS_PROTOCOL_SMP:
 600                                asd_unbuild_smp_ascb(a);
 601                                break;
 602                        case SAS_PROTOCOL_SSP:
 603                                asd_unbuild_ssp_ascb(a);
 604                                break;
 605                        default:
 606                                break;
 607                        }
 608                        t->lldd_task = NULL;
 609                }
 610        }
 611        list_del_init(&alist);
 612out_err:
 613        if (ascb)
 614                asd_ascb_free_list(ascb);
 615        asd_can_dequeue(asd_ha, 1);
 616        return res;
 617}
 618