cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-linux
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aic94xx_task.c (16268B)


      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}