Commit 0b576bb7 authored by Shuhei Matsumoto's avatar Shuhei Matsumoto Committed by Tomasz Zawadzki
Browse files

lib/iscsi: Factor out reading PDU payload operation from iscsi_read_pdu() 



This patch follows the last cleanup.

Factor out reading PDU payload operation from iscsi_read_pdu() into a
helper function iscsi_pdu_payload_read(). This reduces the nesting
level, improves the readability, and make the following patches easier.

Signed-off-by: default avatarShuhei Matsumoto <shuhei.matsumoto.xt@hitachi.com>
Change-Id: Ie5f51eedefe00f3b43a7b45dcf84be79f8df4e27
Reviewed-on: https://review.spdk.io/gerrit/c/spdk/spdk/+/6414


Reviewed-by: default avatarZiye Yang <ziye.yang@intel.com>
Reviewed-by: default avatarChangpeng Liu <changpeng.liu@intel.com>
Reviewed-by: default avatarJim Harris <james.r.harris@intel.com>
Tested-by: default avatarSPDK CI Jenkins <sys_sgci@intel.com>
Community-CI: Mellanox Build Bot
parent 36b9a670

lib/iscsi/iscsi.c

+87 −70
Original line number Diff line number Diff line
@@ -4555,15 +4555,93 @@ iscsi_pdu_payload_handle(struct spdk_iscsi_conn *conn, struct spdk_iscsi_pdu *pd 
	return rc;

}



/* Return zero if completed to read payload, positive number if still in progress,

 * or negative number if any error.

 */

static int

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

{

	struct spdk_mempool *pool;

	uint32_t data_len;

	uint32_t crc32c;

	int rc;



	data_len = pdu->data_segment_len;



	if (pdu->data_buf == NULL) {

		if (data_len <= iscsi_get_max_immediate_data_size()) {

			pool = g_iscsi.pdu_immediate_data_pool;

			pdu->data_buf_len = SPDK_BDEV_BUF_SIZE_WITH_MD(iscsi_get_max_immediate_data_size());

		} else if (data_len <= SPDK_ISCSI_MAX_RECV_DATA_SEGMENT_LENGTH) {

			pool = g_iscsi.pdu_data_out_pool;

			pdu->data_buf_len = SPDK_BDEV_BUF_SIZE_WITH_MD(SPDK_ISCSI_MAX_RECV_DATA_SEGMENT_LENGTH);

		} else {

			SPDK_ERRLOG("Data(%d) > MaxSegment(%d)\n",

				    data_len, SPDK_ISCSI_MAX_RECV_DATA_SEGMENT_LENGTH);

			return -1;

		}

		pdu->mobj = spdk_mempool_get(pool);

		if (pdu->mobj == NULL) {

			return 1;

		}

		pdu->data_buf = pdu->mobj->buf;

		pdu->data = pdu->mobj->buf;

		pdu->data_from_mempool = true;

	}



	/* copy the actual data into local buffer */

	if ((pdu->data_valid_bytes < data_len)) {

		rc = iscsi_conn_read_data_segment(conn, pdu, data_len);

		if (rc < 0) {

			return rc;

		}



		pdu->data_valid_bytes += rc;

		if (pdu->data_valid_bytes < data_len) {

			return 1;

		}

	}



	/* copy out the data digest */

	if (conn->data_digest &&

	    pdu->ddigest_valid_bytes < ISCSI_DIGEST_LEN) {

		rc = iscsi_conn_read_data(conn,

					  ISCSI_DIGEST_LEN - pdu->ddigest_valid_bytes,

					  pdu->data_digest + pdu->ddigest_valid_bytes);

		if (rc < 0) {

			return rc;

		}



		pdu->ddigest_valid_bytes += rc;

		if (pdu->ddigest_valid_bytes < ISCSI_DIGEST_LEN) {

			return 1;

		}

	}



	/* All data for this PDU has now been read from the socket. */

	spdk_trace_record(TRACE_ISCSI_READ_PDU, conn->id, pdu->data_valid_bytes,

			  (uintptr_t)pdu, pdu->bhs.opcode);



	/* check data digest */

	if (conn->data_digest) {

		crc32c = iscsi_pdu_calc_data_digest(pdu);

		rc = MATCH_DIGEST_WORD(pdu->data_digest, crc32c);

		if (rc == 0) {

			SPDK_ERRLOG("data digest error (%s)\n", conn->initiator_name);

			return -1;

		}

	}



	return 0;

}



static int

iscsi_read_pdu(struct spdk_iscsi_conn *conn)

{

	enum iscsi_pdu_recv_state prev_state;

	struct spdk_iscsi_pdu *pdu;

	struct spdk_mempool *pool;

	uint32_t crc32c;

	int ahs_len;

	uint32_t data_len;

	int rc;



	do {
@@ -4668,76 +4746,15 @@ iscsi_read_pdu(struct spdk_iscsi_conn *conn) 
			conn->pdu_recv_state = ISCSI_PDU_RECV_STATE_AWAIT_PDU_PAYLOAD;

			break;

		case ISCSI_PDU_RECV_STATE_AWAIT_PDU_PAYLOAD:

			data_len = pdu->data_segment_len;

			if (data_len != 0) {

				if (pdu->data_buf == NULL) {

					if (data_len <= iscsi_get_max_immediate_data_size()) {

						pool = g_iscsi.pdu_immediate_data_pool;

						pdu->data_buf_len = SPDK_BDEV_BUF_SIZE_WITH_MD(iscsi_get_max_immediate_data_size());

					} else if (data_len <= SPDK_ISCSI_MAX_RECV_DATA_SEGMENT_LENGTH) {

						pool = g_iscsi.pdu_data_out_pool;

						pdu->data_buf_len = SPDK_BDEV_BUF_SIZE_WITH_MD(SPDK_ISCSI_MAX_RECV_DATA_SEGMENT_LENGTH);

					} else {

						SPDK_ERRLOG("Data(%d) > MaxSegment(%d)\n",

							    data_len, SPDK_ISCSI_MAX_RECV_DATA_SEGMENT_LENGTH);

						conn->pdu_recv_state = ISCSI_PDU_RECV_STATE_ERROR;

						break;

					}

					pdu->mobj = spdk_mempool_get(pool);

					if (pdu->mobj == NULL) {

						return 0;

					}

					pdu->data_buf = pdu->mobj->buf;

					pdu->data = pdu->mobj->buf;

					pdu->data_from_mempool = true;

				}



				/* copy the actual data into local buffer */

				if ((pdu->data_valid_bytes < data_len)) {

					rc = iscsi_conn_read_data_segment(conn, pdu, data_len);

					if (rc < 0) {

						conn->pdu_recv_state = ISCSI_PDU_RECV_STATE_ERROR;

						break;

					}



					pdu->data_valid_bytes += rc;

					if (pdu->data_valid_bytes < data_len) {

						return 0;

					}

				}



				/* copy out the data digest */

				if (conn->data_digest &&

				    pdu->ddigest_valid_bytes < ISCSI_DIGEST_LEN) {

					rc = iscsi_conn_read_data(conn,

								  ISCSI_DIGEST_LEN - pdu->ddigest_valid_bytes,

								  pdu->data_digest + pdu->ddigest_valid_bytes);

					if (rc < 0) {

						conn->pdu_recv_state = ISCSI_PDU_RECV_STATE_ERROR;

						break;

					}



					pdu->ddigest_valid_bytes += rc;

					if (pdu->ddigest_valid_bytes < ISCSI_DIGEST_LEN) {

			if (pdu->data_segment_len != 0) {

				rc = iscsi_pdu_payload_read(conn, pdu);

				if (rc > 0) {

					return 0;

					}

				}



				/* All data for this PDU has now been read from the socket. */

				spdk_trace_record(TRACE_ISCSI_READ_PDU, conn->id, pdu->data_valid_bytes,

						  (uintptr_t)pdu, pdu->bhs.opcode);



				/* check data digest */

				if (conn->data_digest) {

					crc32c = iscsi_pdu_calc_data_digest(pdu);

					rc = MATCH_DIGEST_WORD(pdu->data_digest, crc32c);

					if (rc == 0) {

						SPDK_ERRLOG("data digest error (%s)\n", conn->initiator_name);

				} else if (rc < 0) {

					conn->pdu_recv_state = ISCSI_PDU_RECV_STATE_ERROR;

					break;

				}

			}

			}



			if (!pdu->is_rejected) {

				rc = iscsi_pdu_payload_handle(conn, pdu);