Commit fd6efc7f authored by Shuhei Matsumoto's avatar Shuhei Matsumoto Committed by Changpeng Liu
Browse files

lib/iscsi: Remove unnecessary declarations about task queueing functions 



We can remove unnecessary function declarations and make the
structure of the source code top-down.

Signed-off-by: default avatarShuhei Matsumoto <shuhei.matsumoto.xt@hitachi.com>
Change-Id: I8d00c6cec0c0d05a6cd3b70e92062ce9c315ff3b
Reviewed-on: https://review.gerrithub.io/c/spdk/spdk/+/470261


Tested-by: default avatarSPDK CI Jenkins <sys_sgci@intel.com>
Reviewed-by: default avatarBen Walker <benjamin.walker@intel.com>
Reviewed-by: default avatarJim Harris <james.r.harris@intel.com>
parent d8fa5bc1

lib/iscsi/iscsi.c

+176 −179
Original line number Diff line number Diff line
@@ -76,9 +76,6 @@ struct spdk_iscsi_globals g_spdk_iscsi = { 
	.poll_group_head = TAILQ_HEAD_INITIALIZER(g_spdk_iscsi.poll_group_head),

};



static int add_transfer_task(struct spdk_iscsi_conn *conn,

			     struct spdk_iscsi_task *task);



static int iscsi_send_r2t(struct spdk_iscsi_conn *conn,

			  struct spdk_iscsi_task *task, int offset,

			  int len, uint32_t transfer_tag, uint32_t *R2TSN);
@@ -2557,6 +2554,182 @@ iscsi_op_logout(struct spdk_iscsi_conn *conn, struct spdk_iscsi_pdu *pdu) 
	return 0;

}



static int

add_transfer_task(struct spdk_iscsi_conn *conn, struct spdk_iscsi_task *task)

{

	uint32_t transfer_len;

	size_t max_burst_len;

	size_t segment_len;

	size_t data_len;

	int len;

	int idx;

	int rc;

	int data_out_req;



	transfer_len = task->scsi.transfer_len;

	data_len = spdk_iscsi_task_get_pdu(task)->data_segment_len;

	max_burst_len = conn->sess->MaxBurstLength;

	segment_len = SPDK_ISCSI_MAX_RECV_DATA_SEGMENT_LENGTH;

	data_out_req = 1 + (transfer_len - data_len - 1) / segment_len;

	task->data_out_cnt = data_out_req;



	/*

	 * If we already have too many tasks using R2T, then queue this task

	 *  and start sending R2T for it after some of the tasks using R2T/data

	 *  out buffers complete.

	 */

	if (conn->pending_r2t >= DEFAULT_MAXR2T) {

		TAILQ_INSERT_TAIL(&conn->queued_r2t_tasks, task, link);

		return 0;

	}



	conn->data_out_cnt += data_out_req;

	idx = conn->pending_r2t++;



	conn->outstanding_r2t_tasks[idx] = task;

	task->next_expected_r2t_offset = data_len;

	task->current_r2t_length = 0;

	task->R2TSN = 0;

	/* According to RFC3720 10.8.5, 0xffffffff is

	 * reserved for TTT in R2T.

	 */

	if (++conn->ttt == 0xffffffffu) {

		conn->ttt = 0;

	}

	task->ttt = conn->ttt;



	while (data_len != transfer_len) {

		len = DMIN32(max_burst_len, (transfer_len - data_len));

		rc = iscsi_send_r2t(conn, task, data_len, len,

				    task->ttt, &task->R2TSN);

		if (rc < 0) {

			SPDK_ERRLOG("iscsi_send_r2t() failed\n");

			return rc;

		}

		data_len += len;

		task->next_r2t_offset = data_len;

		task->outstanding_r2t++;

		if (conn->sess->MaxOutstandingR2T == task->outstanding_r2t) {

			break;

		}

	}



	TAILQ_INSERT_TAIL(&conn->active_r2t_tasks, task, link);

	return 0;

}



/* If there are additional large writes queued for R2Ts, start them now.

 *  This is called when a large write is just completed or when multiple LUNs

 *  are attached and large write tasks for the specific LUN are cleared.

 */

static void

start_queued_transfer_tasks(struct spdk_iscsi_conn *conn)

{

	struct spdk_iscsi_task *task, *tmp;



	TAILQ_FOREACH_SAFE(task, &conn->queued_r2t_tasks, link, tmp) {

		if (conn->pending_r2t < DEFAULT_MAXR2T) {

			TAILQ_REMOVE(&conn->queued_r2t_tasks, task, link);

			add_transfer_task(conn, task);

		} else {

			break;

		}

	}

}



void spdk_del_transfer_task(struct spdk_iscsi_conn *conn, uint32_t task_tag)

{

	struct spdk_iscsi_task *task;

	int i;



	for (i = 0; i < conn->pending_r2t; i++) {

		if (conn->outstanding_r2t_tasks[i]->tag == task_tag) {

			task = conn->outstanding_r2t_tasks[i];

			conn->data_out_cnt -= task->data_out_cnt;



			conn->pending_r2t--;

			for (; i < conn->pending_r2t; i++) {

				conn->outstanding_r2t_tasks[i] = conn->outstanding_r2t_tasks[i + 1];

			}

			conn->outstanding_r2t_tasks[conn->pending_r2t] = NULL;

			break;

		}

	}



	start_queued_transfer_tasks(conn);

}



static void

del_connection_queued_task(struct spdk_iscsi_conn *conn, void *tailq,

			   struct spdk_scsi_lun *lun,

			   struct spdk_iscsi_pdu *pdu)

{

	struct spdk_iscsi_task *task, *task_tmp;

	struct spdk_iscsi_pdu *pdu_tmp;



	/*

	 * Temporary used to index spdk_scsi_task related

	 *  queues of the connection.

	 */

	TAILQ_HEAD(queued_tasks, spdk_iscsi_task) *head;

	head = (struct queued_tasks *)tailq;



	TAILQ_FOREACH_SAFE(task, head, link, task_tmp) {

		pdu_tmp = spdk_iscsi_task_get_pdu(task);

		if ((lun == NULL || lun == task->scsi.lun) &&

		    (pdu == NULL || SN32_LT(pdu_tmp->cmd_sn, pdu->cmd_sn))) {

			TAILQ_REMOVE(head, task, link);

			if (lun != NULL && spdk_scsi_lun_is_removing(lun)) {

				spdk_scsi_task_process_null_lun(&task->scsi);

				spdk_iscsi_task_response(conn, task);

			}

			spdk_iscsi_task_put(task);

		}

	}

}



void spdk_clear_all_transfer_task(struct spdk_iscsi_conn *conn,

				  struct spdk_scsi_lun *lun,

				  struct spdk_iscsi_pdu *pdu)

{

	int i, j, pending_r2t;

	struct spdk_iscsi_task *task;

	struct spdk_iscsi_pdu *pdu_tmp;



	pending_r2t = conn->pending_r2t;

	for (i = 0; i < pending_r2t; i++) {

		task = conn->outstanding_r2t_tasks[i];

		pdu_tmp = spdk_iscsi_task_get_pdu(task);

		if ((lun == NULL || lun == task->scsi.lun) &&

		    (pdu == NULL || SN32_LT(pdu_tmp->cmd_sn, pdu->cmd_sn))) {

			conn->outstanding_r2t_tasks[i] = NULL;

			task->outstanding_r2t = 0;

			task->next_r2t_offset = 0;

			task->next_expected_r2t_offset = 0;

			conn->data_out_cnt -= task->data_out_cnt;

			conn->pending_r2t--;

		}

	}



	for (i = 0; i < pending_r2t; i++) {

		if (conn->outstanding_r2t_tasks[i] != NULL) {

			continue;

		}

		for (j = i + 1; j < pending_r2t; j++) {

			if (conn->outstanding_r2t_tasks[j] != NULL) {

				conn->outstanding_r2t_tasks[i] = conn->outstanding_r2t_tasks[j];

				conn->outstanding_r2t_tasks[j] = NULL;

				break;

			}

		}

	}



	del_connection_queued_task(conn, &conn->active_r2t_tasks, lun, pdu);

	del_connection_queued_task(conn, &conn->queued_r2t_tasks, lun, pdu);



	start_queued_transfer_tasks(conn);

}



/* This function returns the spdk_scsi_task by searching the snack list via

 * task transfertag and the pdu's opcode

 */
@@ -3637,182 +3810,6 @@ iscsi_op_nopout(struct spdk_iscsi_conn *conn, struct spdk_iscsi_pdu *pdu) 
	return 0;

}



static int

add_transfer_task(struct spdk_iscsi_conn *conn, struct spdk_iscsi_task *task)

{

	uint32_t transfer_len;

	size_t max_burst_len;

	size_t segment_len;

	size_t data_len;

	int len;

	int idx;

	int rc;

	int data_out_req;



	transfer_len = task->scsi.transfer_len;

	data_len = spdk_iscsi_task_get_pdu(task)->data_segment_len;

	max_burst_len = conn->sess->MaxBurstLength;

	segment_len = SPDK_ISCSI_MAX_RECV_DATA_SEGMENT_LENGTH;

	data_out_req = 1 + (transfer_len - data_len - 1) / segment_len;

	task->data_out_cnt = data_out_req;



	/*

	 * If we already have too many tasks using R2T, then queue this task

	 *  and start sending R2T for it after some of the tasks using R2T/data

	 *  out buffers complete.

	 */

	if (conn->pending_r2t >= DEFAULT_MAXR2T) {

		TAILQ_INSERT_TAIL(&conn->queued_r2t_tasks, task, link);

		return 0;

	}



	conn->data_out_cnt += data_out_req;

	idx = conn->pending_r2t++;



	conn->outstanding_r2t_tasks[idx] = task;

	task->next_expected_r2t_offset = data_len;

	task->current_r2t_length = 0;

	task->R2TSN = 0;

	/* According to RFC3720 10.8.5, 0xffffffff is

	 * reserved for TTT in R2T.

	 */

	if (++conn->ttt == 0xffffffffu) {

		conn->ttt = 0;

	}

	task->ttt = conn->ttt;



	while (data_len != transfer_len) {

		len = DMIN32(max_burst_len, (transfer_len - data_len));

		rc = iscsi_send_r2t(conn, task, data_len, len,

				    task->ttt, &task->R2TSN);

		if (rc < 0) {

			SPDK_ERRLOG("iscsi_send_r2t() failed\n");

			return rc;

		}

		data_len += len;

		task->next_r2t_offset = data_len;

		task->outstanding_r2t++;

		if (conn->sess->MaxOutstandingR2T == task->outstanding_r2t) {

			break;

		}

	}



	TAILQ_INSERT_TAIL(&conn->active_r2t_tasks, task, link);

	return 0;

}



/* If there are additional large writes queued for R2Ts, start them now.

 *  This is called when a large write is just completed or when multiple LUNs

 *  are attached and large write tasks for the specific LUN are cleared.

 */

static void

start_queued_transfer_tasks(struct spdk_iscsi_conn *conn)

{

	struct spdk_iscsi_task *task, *tmp;



	TAILQ_FOREACH_SAFE(task, &conn->queued_r2t_tasks, link, tmp) {

		if (conn->pending_r2t < DEFAULT_MAXR2T) {

			TAILQ_REMOVE(&conn->queued_r2t_tasks, task, link);

			add_transfer_task(conn, task);

		} else {

			break;

		}

	}

}



void spdk_del_transfer_task(struct spdk_iscsi_conn *conn, uint32_t task_tag)

{

	struct spdk_iscsi_task *task;

	int i;



	for (i = 0; i < conn->pending_r2t; i++) {

		if (conn->outstanding_r2t_tasks[i]->tag == task_tag) {

			task = conn->outstanding_r2t_tasks[i];

			conn->data_out_cnt -= task->data_out_cnt;



			conn->pending_r2t--;

			for (; i < conn->pending_r2t; i++) {

				conn->outstanding_r2t_tasks[i] = conn->outstanding_r2t_tasks[i + 1];

			}

			conn->outstanding_r2t_tasks[conn->pending_r2t] = NULL;

			break;

		}

	}



	start_queued_transfer_tasks(conn);

}



static void

del_connection_queued_task(struct spdk_iscsi_conn *conn, void *tailq,

			   struct spdk_scsi_lun *lun,

			   struct spdk_iscsi_pdu *pdu)

{

	struct spdk_iscsi_task *task, *task_tmp;

	struct spdk_iscsi_pdu *pdu_tmp;



	/*

	 * Temporary used to index spdk_scsi_task related

	 *  queues of the connection.

	 */

	TAILQ_HEAD(queued_tasks, spdk_iscsi_task) *head;

	head = (struct queued_tasks *)tailq;



	TAILQ_FOREACH_SAFE(task, head, link, task_tmp) {

		pdu_tmp = spdk_iscsi_task_get_pdu(task);

		if ((lun == NULL || lun == task->scsi.lun) &&

		    (pdu == NULL || SN32_LT(pdu_tmp->cmd_sn, pdu->cmd_sn))) {

			TAILQ_REMOVE(head, task, link);

			if (lun != NULL && spdk_scsi_lun_is_removing(lun)) {

				spdk_scsi_task_process_null_lun(&task->scsi);

				spdk_iscsi_task_response(conn, task);

			}

			spdk_iscsi_task_put(task);

		}

	}

}



void spdk_clear_all_transfer_task(struct spdk_iscsi_conn *conn,

				  struct spdk_scsi_lun *lun,

				  struct spdk_iscsi_pdu *pdu)

{

	int i, j, pending_r2t;

	struct spdk_iscsi_task *task;

	struct spdk_iscsi_pdu *pdu_tmp;



	pending_r2t = conn->pending_r2t;

	for (i = 0; i < pending_r2t; i++) {

		task = conn->outstanding_r2t_tasks[i];

		pdu_tmp = spdk_iscsi_task_get_pdu(task);

		if ((lun == NULL || lun == task->scsi.lun) &&

		    (pdu == NULL || SN32_LT(pdu_tmp->cmd_sn, pdu->cmd_sn))) {

			conn->outstanding_r2t_tasks[i] = NULL;

			task->outstanding_r2t = 0;

			task->next_r2t_offset = 0;

			task->next_expected_r2t_offset = 0;

			conn->data_out_cnt -= task->data_out_cnt;

			conn->pending_r2t--;

		}

	}



	for (i = 0; i < pending_r2t; i++) {

		if (conn->outstanding_r2t_tasks[i] != NULL) {

			continue;

		}

		for (j = i + 1; j < pending_r2t; j++) {

			if (conn->outstanding_r2t_tasks[j] != NULL) {

				conn->outstanding_r2t_tasks[i] = conn->outstanding_r2t_tasks[j];

				conn->outstanding_r2t_tasks[j] = NULL;

				break;

			}

		}

	}



	del_connection_queued_task(conn, &conn->active_r2t_tasks, lun, pdu);

	del_connection_queued_task(conn, &conn->queued_r2t_tasks, lun, pdu);



	start_queued_transfer_tasks(conn);

}



/* This function is used to handle the r2t snack */

static int

iscsi_handle_r2t_snack(struct spdk_iscsi_conn *conn,