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[SCSI] isci: atapi support

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Based on original implementation from Jiangbi Liu and Maciej Trela.

ATAPI transfers happen in two-to-three stages.  The two stage atapi
commands are those that include a dma data transfer.  The data transfer
portion of these operations is handled by the hardware packet-dma
acceleration.  The three-stage commands do not have a data transfer and
are handled without hardware assistance in raw frame mode.

stage1: transmit host-to-device fis to notify the device of an incoming
atapi cdb.  Upon reception of the pio-setup-fis repost the task_context
to perform the dma transfer of the cdb+data (go to stage3), or repost
the task_context to transmit the cdb as a raw frame (go to stage 2).

stage2: wait for hardware notification of the cdb transmission and then
go to stage 3.

stage3: wait for the arrival of the terminating device-to-host fis and
terminate the command.

To keep the implementation simple we only support ATAPI packet-dma
protocol (for commands with data) to avoid needing to handle the data
transfer manually (like we do for SATA-PIO).  This may affect
compatibility for a small number of devices (see
ATA_HORKAGE_ATAPI_MOD16_DMA).

If the data-transfer underruns, or encounters an error the
device-to-host fis is expected to arrive in the unsolicited frame queue
to pass to libata for disposition.  However, in the DONE_UNEXP_FIS (data
underrun) case it appears we need to craft a response.  In the
DONE_REG_ERR case we do receive the UF and propagate it to libsas.

Signed-off-by: Maciej Trela <maciej.trela@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
This commit is contained in:
Dan Williams 2011-09-30 18:52:19 -07:00 committed by James Bottomley
parent 4f3f812dd3
commit b50102d3e9
6 changed files with 380 additions and 16 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

24
drivers/scsi/isci/remote_device.c
View File

@ -386,6 +386,18 @@ static bool is_remote_device_ready(struct isci_remote_device *idev)
}
}
/*
* called once the remote node context has transisitioned to a ready
* state (after suspending RX and/or TX due to early D2H fis)
*/
static void atapi_remote_device_resume_done(void *_dev)
{
struct isci_remote_device *idev = _dev;
struct isci_request *ireq = idev->working_request;
sci_change_state(&ireq->sm, SCI_REQ_COMPLETED);
}
enum sci_status sci_remote_device_event_handler(struct isci_remote_device *idev,
u32 event_code)
{
@ -432,6 +444,16 @@ enum sci_status sci_remote_device_event_handler(struct isci_remote_device *idev,
if (status != SCI_SUCCESS)
return status;
if (state == SCI_STP_DEV_ATAPI_ERROR) {
/* For ATAPI error state resume the RNC right away. */
if (scu_get_event_type(event_code) == SCU_EVENT_TYPE_RNC_SUSPEND_TX ||
scu_get_event_type(event_code) == SCU_EVENT_TYPE_RNC_SUSPEND_TX_RX) {
return sci_remote_node_context_resume(&idev->rnc,
atapi_remote_device_resume_done,
idev);
}
}
if (state == SCI_STP_DEV_IDLE) {
/* We pick up suspension events to handle specifically to this
@ -625,6 +647,7 @@ enum sci_status sci_remote_device_complete_io(struct isci_host *ihost,
case SCI_STP_DEV_CMD:
case SCI_STP_DEV_NCQ:
case SCI_STP_DEV_NCQ_ERROR:
case SCI_STP_DEV_ATAPI_ERROR:
status = common_complete_io(iport, idev, ireq);
if (status != SCI_SUCCESS)
break;
@ -1020,6 +1043,7 @@ static const struct sci_base_state sci_remote_device_state_table[] = {
[SCI_STP_DEV_NCQ_ERROR] = {
.enter_state = sci_stp_remote_device_ready_ncq_error_substate_enter,
},
[SCI_STP_DEV_ATAPI_ERROR] = { },
[SCI_STP_DEV_AWAIT_RESET] = { },
[SCI_SMP_DEV_IDLE] = {
.enter_state = sci_smp_remote_device_ready_idle_substate_enter,

9
drivers/scsi/isci/remote_device.h
View File

@ -243,6 +243,15 @@ enum sci_remote_device_states {
*/
SCI_STP_DEV_NCQ_ERROR,
/**
* This is the ATAPI error state for the STP ATAPI remote device.
* This state is entered when ATAPI device sends error status FIS
* without data while the device object is in CMD state.
* A suspension event is expected in this state.
* The device object will resume right away.
*/
SCI_STP_DEV_ATAPI_ERROR,
/**
* This is the READY substate indicates the device is waiting for the RESET task
* coming to be recovered from certain hardware specific error.

328
drivers/scsi/isci/request.c
View File

@ -481,7 +481,29 @@ static void sci_stp_optimized_request_construct(struct isci_request *ireq,
}
}
static void sci_atapi_construct(struct isci_request *ireq)
{
struct host_to_dev_fis *h2d_fis = &ireq->stp.cmd;
struct sas_task *task;
/* To simplify the implementation we take advantage of the
* silicon's partial acceleration of atapi protocol (dma data
* transfers), so we promote all commands to dma protocol. This
* breaks compatibility with ATA_HORKAGE_ATAPI_MOD16_DMA drives.
*/
h2d_fis->features |= ATAPI_PKT_DMA;
scu_stp_raw_request_construct_task_context(ireq);
task = isci_request_access_task(ireq);
if (task->data_dir == DMA_NONE)
task->total_xfer_len = 0;
/* clear the response so we can detect arrivial of an
* unsolicited h2d fis
*/
ireq->stp.rsp.fis_type = 0;
}
static enum sci_status
sci_io_request_construct_sata(struct isci_request *ireq,
@ -491,6 +513,7 @@ sci_io_request_construct_sata(struct isci_request *ireq,
{
enum sci_status status = SCI_SUCCESS;
struct sas_task *task = isci_request_access_task(ireq);
struct domain_device *dev = ireq->target_device->domain_dev;
/* check for management protocols */
if (ireq->ttype == tmf_task) {
@ -519,6 +542,13 @@ sci_io_request_construct_sata(struct isci_request *ireq,
}
/* ATAPI */
if (dev->sata_dev.command_set == ATAPI_COMMAND_SET &&
task->ata_task.fis.command == ATA_CMD_PACKET) {
sci_atapi_construct(ireq);
return SCI_SUCCESS;
}
/* non data */
if (task->data_dir == DMA_NONE) {
scu_stp_raw_request_construct_task_context(ireq);
@ -627,7 +657,7 @@ enum sci_status sci_task_request_construct_sata(struct isci_request *ireq)
/**
* sci_req_tx_bytes - bytes transferred when reply underruns request
* @sci_req: request that was terminated early
* @ireq: request that was terminated early
*/
#define SCU_TASK_CONTEXT_SRAM 0x200000
static u32 sci_req_tx_bytes(struct isci_request *ireq)
@ -729,6 +759,10 @@ sci_io_request_terminate(struct isci_request *ireq)
case SCI_REQ_STP_SOFT_RESET_WAIT_H2D_ASSERTED:
case SCI_REQ_STP_SOFT_RESET_WAIT_H2D_DIAG:
case SCI_REQ_STP_SOFT_RESET_WAIT_D2H:
case SCI_REQ_ATAPI_WAIT_H2D:
case SCI_REQ_ATAPI_WAIT_PIO_SETUP:
case SCI_REQ_ATAPI_WAIT_D2H:
case SCI_REQ_ATAPI_WAIT_TC_COMP:
sci_change_state(&ireq->sm, SCI_REQ_ABORTING);
return SCI_SUCCESS;
case SCI_REQ_TASK_WAIT_TC_RESP:
@ -1194,8 +1228,8 @@ static enum sci_status sci_stp_request_pio_data_out_transmit_data(struct isci_re
{
struct isci_stp_request *stp_req = &ireq->stp.req;
struct scu_sgl_element_pair *sgl_pair;
enum sci_status status = SCI_SUCCESS;
struct scu_sgl_element *sgl;
enum sci_status status;
u32 offset;
u32 len = 0;
@ -1249,7 +1283,7 @@ static enum sci_status sci_stp_request_pio_data_out_transmit_data(struct isci_re
*/
static enum sci_status
sci_stp_request_pio_data_in_copy_data_buffer(struct isci_stp_request *stp_req,
u8 *data_buf, u32 len)
u8 *data_buf, u32 len)
{
struct isci_request *ireq;
u8 *src_addr;
@ -1423,6 +1457,128 @@ static enum sci_status sci_stp_request_udma_general_frame_handler(struct isci_re
return status;
}
static enum sci_status process_unsolicited_fis(struct isci_request *ireq,
u32 frame_index)
{
struct isci_host *ihost = ireq->owning_controller;
enum sci_status status;
struct dev_to_host_fis *frame_header;
u32 *frame_buffer;
status = sci_unsolicited_frame_control_get_header(&ihost->uf_control,
frame_index,
(void **)&frame_header);
if (status != SCI_SUCCESS)
return status;
if (frame_header->fis_type != FIS_REGD2H) {
dev_err(&ireq->isci_host->pdev->dev,
"%s ERROR: invalid fis type 0x%X\n",
__func__, frame_header->fis_type);
return SCI_FAILURE;
}
sci_unsolicited_frame_control_get_buffer(&ihost->uf_control,
frame_index,
(void **)&frame_buffer);
sci_controller_copy_sata_response(&ireq->stp.rsp,
(u32 *)frame_header,
frame_buffer);
/* Frame has been decoded return it to the controller */
sci_controller_release_frame(ihost, frame_index);
return status;
}
static enum sci_status atapi_d2h_reg_frame_handler(struct isci_request *ireq,
u32 frame_index)
{
struct sas_task *task = isci_request_access_task(ireq);
enum sci_status status;
status = process_unsolicited_fis(ireq, frame_index);
if (status == SCI_SUCCESS) {
if (ireq->stp.rsp.status & ATA_ERR)
status = SCI_IO_FAILURE_RESPONSE_VALID;
} else {
status = SCI_IO_FAILURE_RESPONSE_VALID;
}
if (status != SCI_SUCCESS) {
ireq->scu_status = SCU_TASK_DONE_CHECK_RESPONSE;
ireq->sci_status = status;
} else {
ireq->scu_status = SCU_TASK_DONE_GOOD;
ireq->sci_status = SCI_SUCCESS;
}
/* the d2h ufi is the end of non-data commands */
if (task->data_dir == DMA_NONE)
sci_change_state(&ireq->sm, SCI_REQ_COMPLETED);
return status;
}
static void scu_atapi_reconstruct_raw_frame_task_context(struct isci_request *ireq)
{
struct ata_device *dev = sas_to_ata_dev(ireq->target_device->domain_dev);
void *atapi_cdb = ireq->ttype_ptr.io_task_ptr->ata_task.atapi_packet;
struct scu_task_context *task_context = ireq->tc;
/* fill in the SCU Task Context for a DATA fis containing CDB in Raw Frame
* type. The TC for previous Packet fis was already there, we only need to
* change the H2D fis content.
*/
memset(&ireq->stp.cmd, 0, sizeof(struct host_to_dev_fis));
memcpy(((u8 *)&ireq->stp.cmd + sizeof(u32)), atapi_cdb, ATAPI_CDB_LEN);
memset(&(task_context->type.stp), 0, sizeof(struct stp_task_context));
task_context->type.stp.fis_type = FIS_DATA;
task_context->transfer_length_bytes = dev->cdb_len;
}
static void scu_atapi_construct_task_context(struct isci_request *ireq)
{
struct ata_device *dev = sas_to_ata_dev(ireq->target_device->domain_dev);
struct sas_task *task = isci_request_access_task(ireq);
struct scu_task_context *task_context = ireq->tc;
int cdb_len = dev->cdb_len;
/* reference: SSTL 1.13.4.2
* task_type, sata_direction
*/
if (task->data_dir == DMA_TO_DEVICE) {
task_context->task_type = SCU_TASK_TYPE_PACKET_DMA_OUT;
task_context->sata_direction = 0;
} else {
/* todo: for NO_DATA command, we need to send out raw frame. */
task_context->task_type = SCU_TASK_TYPE_PACKET_DMA_IN;
task_context->sata_direction = 1;
}
memset(&task_context->type.stp, 0, sizeof(task_context->type.stp));
task_context->type.stp.fis_type = FIS_DATA;
memset(&ireq->stp.cmd, 0, sizeof(ireq->stp.cmd));
memcpy(&ireq->stp.cmd.lbal, task->ata_task.atapi_packet, cdb_len);
task_context->ssp_command_iu_length = cdb_len / sizeof(u32);
/* task phase is set to TX_CMD */
task_context->task_phase = 0x1;
/* retry counter */
task_context->stp_retry_count = 0;
/* data transfer size. */
task_context->transfer_length_bytes = task->total_xfer_len;
/* setup sgl */
sci_request_build_sgl(ireq);
}
enum sci_status
sci_io_request_frame_handler(struct isci_request *ireq,
u32 frame_index)
@ -1835,6 +1991,24 @@ sci_io_request_frame_handler(struct isci_request *ireq,
return status;
}
case SCI_REQ_ATAPI_WAIT_PIO_SETUP: {
struct sas_task *task = isci_request_access_task(ireq);
sci_controller_release_frame(ihost, frame_index);
ireq->target_device->working_request = ireq;
if (task->data_dir == DMA_NONE) {
sci_change_state(&ireq->sm, SCI_REQ_ATAPI_WAIT_TC_COMP);
scu_atapi_reconstruct_raw_frame_task_context(ireq);
} else {
sci_change_state(&ireq->sm, SCI_REQ_ATAPI_WAIT_D2H);
scu_atapi_construct_task_context(ireq);
}
sci_controller_continue_io(ireq);
return SCI_SUCCESS;
}
case SCI_REQ_ATAPI_WAIT_D2H:
return atapi_d2h_reg_frame_handler(ireq, frame_index);
case SCI_REQ_ABORTING:
/*
* TODO: Is it even possible to get an unsolicited frame in the
@ -1966,6 +2140,112 @@ stp_request_soft_reset_await_h2d_diagnostic_tc_event(struct isci_request *ireq,
return SCI_SUCCESS;
}
static enum sci_status atapi_raw_completion(struct isci_request *ireq, u32 completion_code,
enum sci_base_request_states next)
{
enum sci_status status = SCI_SUCCESS;
switch (SCU_GET_COMPLETION_TL_STATUS(completion_code)) {
case SCU_MAKE_COMPLETION_STATUS(SCU_TASK_DONE_GOOD):
ireq->scu_status = SCU_TASK_DONE_GOOD;
ireq->sci_status = SCI_SUCCESS;
sci_change_state(&ireq->sm, next);
break;
default:
/* All other completion status cause the IO to be complete.
* If a NAK was received, then it is up to the user to retry
* the request.
*/
ireq->scu_status = SCU_NORMALIZE_COMPLETION_STATUS(completion_code);
ireq->sci_status = SCI_FAILURE_CONTROLLER_SPECIFIC_IO_ERR;
sci_change_state(&ireq->sm, SCI_REQ_COMPLETED);
break;
}
return status;
}
static enum sci_status atapi_data_tc_completion_handler(struct isci_request *ireq,
u32 completion_code)
{
struct isci_remote_device *idev = ireq->target_device;
struct dev_to_host_fis *d2h = &ireq->stp.rsp;
enum sci_status status = SCI_SUCCESS;
switch (SCU_GET_COMPLETION_TL_STATUS(completion_code)) {
case (SCU_TASK_DONE_GOOD << SCU_COMPLETION_TL_STATUS_SHIFT):
sci_change_state(&ireq->sm, SCI_REQ_COMPLETED);
break;
case (SCU_TASK_DONE_UNEXP_FIS << SCU_COMPLETION_TL_STATUS_SHIFT): {
u16 len = sci_req_tx_bytes(ireq);
/* likely non-error data underrrun, workaround missing
* d2h frame from the controller
*/
if (d2h->fis_type != FIS_REGD2H) {
d2h->fis_type = FIS_REGD2H;
d2h->flags = (1 << 6);
d2h->status = 0x50;
d2h->error = 0;
d2h->lbal = 0;
d2h->byte_count_low = len & 0xff;
d2h->byte_count_high = len >> 8;
d2h->device = 0xa0;
d2h->lbal_exp = 0;
d2h->lbam_exp = 0;
d2h->lbah_exp = 0;
d2h->_r_a = 0;
d2h->sector_count = 0x3;
d2h->sector_count_exp = 0;
d2h->_r_b = 0;
d2h->_r_c = 0;
d2h->_r_d = 0;
}
ireq->scu_status = SCU_TASK_DONE_GOOD;
ireq->sci_status = SCI_SUCCESS_IO_DONE_EARLY;
status = ireq->sci_status;
/* the hw will have suspended the rnc, so complete the
* request upon pending resume
*/
sci_change_state(&idev->sm, SCI_STP_DEV_ATAPI_ERROR);
break;
}
case (SCU_TASK_DONE_EXCESS_DATA << SCU_COMPLETION_TL_STATUS_SHIFT):
/* In this case, there is no UF coming after.
* compelte the IO now.
*/
ireq->scu_status = SCU_TASK_DONE_GOOD;
ireq->sci_status = SCI_SUCCESS;
sci_change_state(&ireq->sm, SCI_REQ_COMPLETED);
break;
default:
if (d2h->fis_type == FIS_REGD2H) {
/* UF received change the device state to ATAPI_ERROR */
status = ireq->sci_status;
sci_change_state(&idev->sm, SCI_STP_DEV_ATAPI_ERROR);
} else {
/* If receiving any non-sucess TC status, no UF
* received yet, then an UF for the status fis
* is coming after (XXX: suspect this is
* actually a protocol error or a bug like the
* DONE_UNEXP_FIS case)
*/
ireq->scu_status = SCU_TASK_DONE_CHECK_RESPONSE;
ireq->sci_status = SCI_FAILURE_IO_RESPONSE_VALID;
sci_change_state(&ireq->sm, SCI_REQ_ATAPI_WAIT_D2H);
}
break;
}
return status;
}
enum sci_status
sci_io_request_tc_completion(struct isci_request *ireq,
u32 completion_code)
@ -2017,6 +2297,17 @@ sci_io_request_tc_completion(struct isci_request *ireq,
return request_aborting_state_tc_event(ireq,
completion_code);
case SCI_REQ_ATAPI_WAIT_H2D:
return atapi_raw_completion(ireq, completion_code,
SCI_REQ_ATAPI_WAIT_PIO_SETUP);
case SCI_REQ_ATAPI_WAIT_TC_COMP:
return atapi_raw_completion(ireq, completion_code,
SCI_REQ_ATAPI_WAIT_D2H);
case SCI_REQ_ATAPI_WAIT_D2H:
return atapi_data_tc_completion_handler(ireq, completion_code);
default:
dev_warn(&ihost->pdev->dev,
"%s: SCIC IO Request given task completion "
@ -2423,6 +2714,8 @@ static void isci_process_stp_response(struct sas_task *task, struct dev_to_host_
*/
if (fis->status & ATA_DF)
ts->stat = SAS_PROTO_RESPONSE;
else if (fis->status & ATA_ERR)
ts->stat = SAM_STAT_CHECK_CONDITION;
else
ts->stat = SAM_STAT_GOOD;
@ -2782,6 +3075,7 @@ static void sci_request_started_state_enter(struct sci_base_state_machine *sm)
{
struct isci_request *ireq = container_of(sm, typeof(*ireq), sm);
struct domain_device *dev = ireq->target_device->domain_dev;
enum sci_base_request_states state;
struct sas_task *task;
/* XXX as hch said always creating an internal sas_task for tmf
@ -2793,26 +3087,30 @@ static void sci_request_started_state_enter(struct sci_base_state_machine *sm)
* substates
*/
if (!task && dev->dev_type == SAS_END_DEV) {
sci_change_state(sm, SCI_REQ_TASK_WAIT_TC_COMP);
state = SCI_REQ_TASK_WAIT_TC_COMP;
} else if (!task &&
(isci_request_access_tmf(ireq)->tmf_code == isci_tmf_sata_srst_high ||
isci_request_access_tmf(ireq)->tmf_code == isci_tmf_sata_srst_low)) {
sci_change_state(sm, SCI_REQ_STP_SOFT_RESET_WAIT_H2D_ASSERTED);
state = SCI_REQ_STP_SOFT_RESET_WAIT_H2D_ASSERTED;
} else if (task && task->task_proto == SAS_PROTOCOL_SMP) {
sci_change_state(sm, SCI_REQ_SMP_WAIT_RESP);
state = SCI_REQ_SMP_WAIT_RESP;
} else if (task && sas_protocol_ata(task->task_proto) &&
!task->ata_task.use_ncq) {
u32 state;
if (task->data_dir == DMA_NONE)
if (dev->sata_dev.command_set == ATAPI_COMMAND_SET &&
task->ata_task.fis.command == ATA_CMD_PACKET) {
state = SCI_REQ_ATAPI_WAIT_H2D;
} else if (task->data_dir == DMA_NONE) {
state = SCI_REQ_STP_NON_DATA_WAIT_H2D;
else if (task->ata_task.dma_xfer)
} else if (task->ata_task.dma_xfer) {
state = SCI_REQ_STP_UDMA_WAIT_TC_COMP;
else /* PIO */
} else /* PIO */ {
state = SCI_REQ_STP_PIO_WAIT_H2D;
sci_change_state(sm, state);
}
} else {
/* SSP or NCQ are fully accelerated, no substates */
return;
}
sci_change_state(sm, state);
}
static void sci_request_completed_state_enter(struct sci_base_state_machine *sm)
@ -2904,6 +3202,10 @@ static const struct sci_base_state sci_request_state_table[] = {
[SCI_REQ_TASK_WAIT_TC_RESP] = { },
[SCI_REQ_SMP_WAIT_RESP] = { },
[SCI_REQ_SMP_WAIT_TC_COMP] = { },
[SCI_REQ_ATAPI_WAIT_H2D] = { },
[SCI_REQ_ATAPI_WAIT_PIO_SETUP] = { },
[SCI_REQ_ATAPI_WAIT_D2H] = { },
[SCI_REQ_ATAPI_WAIT_TC_COMP] = { },
[SCI_REQ_COMPLETED] = {
.enter_state = sci_request_completed_state_enter,
},

28
drivers/scsi/isci/request.h
View File

@ -96,7 +96,6 @@ enum sci_request_protocol {
* to wait for another fis or if the transfer is complete. Upon
* receipt of a d2h fis this will be the status field of that fis.
* @sgl - track pio transfer progress as we iterate through the sgl
* @device_cdb_len - atapi device advertises it's transfer constraints at setup
*/
struct isci_stp_request {
u32 pio_len;
@ -107,7 +106,6 @@ struct isci_stp_request {
u8 set;
u32 offset;
} sgl;
u32 device_cdb_len;
};
struct isci_request {
@ -248,6 +246,32 @@ enum sci_base_request_states {
*/
SCI_REQ_STP_PIO_DATA_OUT,
/*
* While in this state the IO request object is waiting for the TC
* completion notification for the H2D Register FIS
*/
SCI_REQ_ATAPI_WAIT_H2D,
/*
* While in this state the IO request object is waiting for either a
* PIO Setup.
*/
SCI_REQ_ATAPI_WAIT_PIO_SETUP,
/*
* The non-data IO transit to this state in this state after receiving
* TC completion. While in this state IO request object is waiting for
* D2H status frame as UF.
*/
SCI_REQ_ATAPI_WAIT_D2H,
/*
* When transmitting raw frames hardware reports task context completion
* after every frame submission, so in the non-accelerated case we need
* to expect the completion for the "cdb" frame.
*/
SCI_REQ_ATAPI_WAIT_TC_COMP,
/*
* The AWAIT_TC_COMPLETION sub-state indicates that the started raw
* task management request is waiting for the transmission of the

2
drivers/scsi/libsas/sas_scsi_host.c
View File

@ -801,7 +801,7 @@ void sas_slave_destroy(struct scsi_device *scsi_dev)
struct domain_device *dev = sdev_to_domain_dev(scsi_dev);
if (dev_is_sata(dev))
dev->sata_dev.ap->link.device[0].class = ATA_DEV_NONE;
sas_to_ata_dev(dev)->class = ATA_DEV_NONE;
}
int sas_change_queue_depth(struct scsi_device *sdev, int depth, int reason)

5
include/scsi/libsas.h
View File

@ -389,6 +389,11 @@ sdev_to_domain_dev(struct scsi_device *sdev) {
return starget_to_domain_dev(sdev->sdev_target);
}
static inline struct ata_device *sas_to_ata_dev(struct domain_device *dev)
{
return &dev->sata_dev.ap->link.device[0];
}
static inline struct domain_device *
cmd_to_domain_dev(struct scsi_cmnd *cmd)
{