Commit 50bd0364 authored by Shuhei Matsumoto's avatar Shuhei Matsumoto Committed by Jim Harris
Browse files

lib/iscsi: Separate PDU header and payload handing for SCSI Data-Out 



To use zero copy bdev I/O APIs, we have to allocate iSCSI task
before allocating data buffer.

Hence we separate PDU header and payload handling for SCSI Data-Out,
and include iSCSI task allocation into PDU header handling.

Factor out PDU header handling in iscsi_op_data() into iscsi_pdu_hdr_op_data().
spdk_nvmf_tcp_h2c_data_hdr_handle() and spdk_nvmf_tcp_h2c_data_payload_handle()
in lib/nvmf/tcp.c are used as a reference implementation.

Use pdu->task to pass the task allocated by iscsi_pdu_hdr_op_data() into
iscsi_op_data().

In iscsi_op_data(), if it sees pdu->is_rejected is true or pdu->task
is NULL, do nothing. Besides, check LUN hot plug again to separate
PDU header handling and PDU payload handling.

Signed-off-by: default avatarShuhei Matsumoto <shuhei.matsumoto.xt@hitachi.com>
Change-Id: I5074e945254081960744577e4ed8e0170793e5e0
Reviewed-on: https://review.gerrithub.io/c/spdk/spdk/+/470291


Tested-by: default avatarSPDK CI Jenkins <sys_sgci@intel.com>
Reviewed-by: default avatarJim Harris <james.r.harris@intel.com>
Reviewed-by: default avatarBen Walker <benjamin.walker@intel.com>
Community-CI: Broadcom SPDK FC-NVMe CI <spdk-ci.pdl@broadcom.com>
parent 6e7473f7

lib/iscsi/iscsi.c

+67 −35
Original line number Diff line number Diff line
@@ -4392,18 +4392,15 @@ iscsi_pdu_hdr_op_snack(struct spdk_iscsi_conn *conn, struct spdk_iscsi_pdu *pdu) 
}



static int

iscsi_op_data(struct spdk_iscsi_conn *conn, struct spdk_iscsi_pdu *pdu)

iscsi_pdu_hdr_op_data(struct spdk_iscsi_conn *conn, struct spdk_iscsi_pdu *pdu)

{

	struct spdk_iscsi_task	*task, *subtask;

	struct iscsi_bhs_data_out *reqh;

	struct spdk_scsi_lun	*lun_dev;

	uint32_t transfer_tag;

	uint32_t task_tag;

	uint32_t transfer_len;

	uint32_t DataSN;

	uint32_t buffer_offset;

	uint32_t len;

	int F_bit;

	int rc;

	int reject_reason = ISCSI_REASON_INVALID_PDU_FIELD;
@@ -4412,18 +4409,17 @@ iscsi_op_data(struct spdk_iscsi_conn *conn, struct spdk_iscsi_pdu *pdu) 
		return SPDK_ISCSI_CONNECTION_FATAL;

	}



	if (pdu->data_segment_len > SPDK_ISCSI_MAX_RECV_DATA_SEGMENT_LENGTH) {

		reject_reason = ISCSI_REASON_PROTOCOL_ERROR;

		goto reject_return;

	}



	reqh = (struct iscsi_bhs_data_out *)&pdu->bhs;

	F_bit = !!(reqh->flags & ISCSI_FLAG_FINAL);

	transfer_tag = from_be32(&reqh->ttt);

	task_tag = from_be32(&reqh->itt);

	DataSN = from_be32(&reqh->data_sn);

	buffer_offset = from_be32(&reqh->buffer_offset);



	if (pdu->data_segment_len > SPDK_ISCSI_MAX_RECV_DATA_SEGMENT_LENGTH) {

		reject_reason = ISCSI_REASON_PROTOCOL_ERROR;

		goto reject_return;

	}



	task = get_transfer_task(conn, transfer_tag);

	if (task == NULL) {

		SPDK_ERRLOG("Not found task for transfer_tag=%x\n", transfer_tag);
@@ -4458,18 +4454,71 @@ iscsi_op_data(struct spdk_iscsi_conn *conn, struct spdk_iscsi_pdu *pdu) 
		return SPDK_ISCSI_CONNECTION_FATAL;

	}



	if (task->current_r2t_length + pdu->data_segment_len > conn->sess->MaxBurstLength) {

		SPDK_ERRLOG("R2T burst(%zu) > MaxBurstLength(%u)\n",

			    task->current_r2t_length + pdu->data_segment_len,

			    conn->sess->MaxBurstLength);

		return SPDK_ISCSI_CONNECTION_FATAL;

	}



	subtask = spdk_iscsi_task_get(conn, task, spdk_iscsi_task_cpl);

	if (subtask == NULL) {

		SPDK_ERRLOG("Unable to acquire subtask\n");

		return SPDK_ISCSI_CONNECTION_FATAL;

	}

	subtask->scsi.offset = buffer_offset;

	subtask->scsi.length = pdu->data_segment_len;

	spdk_iscsi_task_associate_pdu(subtask, pdu);



	if (lun_dev == NULL) {

		SPDK_DEBUGLOG(SPDK_LOG_ISCSI, "LUN %d is removed, complete the task immediately\n",

			      task->lun_id);

		subtask->scsi.transfer_len = subtask->scsi.length;

		spdk_scsi_task_process_null_lun(&subtask->scsi);

		spdk_iscsi_task_cpl(&subtask->scsi);

		return 0;

	}



	pdu->task = subtask;

	return 0;



send_r2t_recovery_return:

	rc = iscsi_send_r2t_recovery(conn, task, task->acked_r2tsn, true);

	if (rc == 0) {

		return 0;

	}



reject_return:

	return iscsi_reject(conn, pdu, reject_reason);

}



static int

iscsi_op_data(struct spdk_iscsi_conn *conn, struct spdk_iscsi_pdu *pdu)

{

	struct spdk_iscsi_task	*task, *subtask;

	struct iscsi_bhs_data_out *reqh;

	uint32_t transfer_len;

	uint32_t len;

	int F_bit;

	int rc;



	rc = iscsi_pdu_hdr_op_data(conn, pdu);

	if (rc != 0 || pdu->is_rejected || pdu->task == NULL) {

		return rc;

	}



	subtask = pdu->task;

	task = spdk_iscsi_task_get_primary(subtask);

	assert(task != subtask);



	reqh = (struct iscsi_bhs_data_out *)&pdu->bhs;

	F_bit = !!(reqh->flags & ISCSI_FLAG_FINAL);



	transfer_len = task->scsi.transfer_len;

	task->current_r2t_length += pdu->data_segment_len;

	task->next_expected_r2t_offset += pdu->data_segment_len;

	task->r2t_datasn++;



	if (task->current_r2t_length > conn->sess->MaxBurstLength) {

		SPDK_ERRLOG("R2T burst(%u) > MaxBurstLength(%u)\n",

			    task->current_r2t_length,

			    conn->sess->MaxBurstLength);

		return SPDK_ISCSI_CONNECTION_FATAL;

	}



	if (F_bit) {

		/*

		 * This R2T burst is done.  Clear the length before we
@@ -4478,19 +4527,11 @@ iscsi_op_data(struct spdk_iscsi_conn *conn, struct spdk_iscsi_pdu *pdu) 
		task->current_r2t_length = 0;

	}



	subtask = spdk_iscsi_task_get(conn, task, spdk_iscsi_task_cpl);

	if (subtask == NULL) {

		SPDK_ERRLOG("Unable to acquire subtask\n");

		return SPDK_ISCSI_CONNECTION_FATAL;

	}

	subtask->scsi.offset = buffer_offset;

	subtask->scsi.length = pdu->data_segment_len;

	if (spdk_likely(!pdu->dif_insert_or_strip)) {

		spdk_scsi_task_set_data(&subtask->scsi, pdu->data, pdu->data_segment_len);

	} else {

		spdk_scsi_task_set_data(&subtask->scsi, pdu->data, pdu->data_buf_len);

	}

	spdk_iscsi_task_associate_pdu(subtask, pdu);



	if (task->next_expected_r2t_offset == transfer_len) {

		task->acked_r2tsn++;
@@ -4506,7 +4547,7 @@ iscsi_op_data(struct spdk_iscsi_conn *conn, struct spdk_iscsi_pdu *pdu) 
		task->next_r2t_offset += len;

	}



	if (lun_dev == NULL) {

	if (spdk_scsi_dev_get_lun(conn->dev, task->lun_id) == NULL) {

		SPDK_DEBUGLOG(SPDK_LOG_ISCSI, "LUN %d is removed, complete the task immediately\n",

			      task->lun_id);

		subtask->scsi.transfer_len = subtask->scsi.length;
@@ -4517,15 +4558,6 @@ iscsi_op_data(struct spdk_iscsi_conn *conn, struct spdk_iscsi_pdu *pdu) 


	iscsi_queue_task(conn, subtask);

	return 0;



send_r2t_recovery_return:

	rc = iscsi_send_r2t_recovery(conn, task, task->acked_r2tsn, true);

	if (rc == 0) {

		return 0;

	}



reject_return:

	return iscsi_reject(conn, pdu, reject_reason);

}



static void