3 files changed, 286 insertions, 420 deletions

diff --git a/drivers/scsi/iscsi_tcp.c b/drivers/scsi/iscsi_tcp.c
index d6927f1a6b65..290c1d76cd40 100644
--- a/drivers/scsi/iscsi_tcp.c
+++ b/drivers/scsi/iscsi_tcp.c
@@ -281,7 +281,6 @@ iscsi_solicit_data_init(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask,
 {
 	struct iscsi_data *hdr;
 	struct scsi_cmnd *sc = ctask->sc;
-	struct iscsi_tcp_cmd_task *tcp_ctask = ctask->dd_data;
 
 	hdr = &r2t->dtask.hdr;
 	memset(hdr, 0, sizeof(struct iscsi_data));
@@ -336,10 +335,12 @@ iscsi_solicit_data_init(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask,
 			sg_count += sg->length;
 		}
 		BUG_ON(r2t->sg == NULL);
-	} else
-		iscsi_buf_init_iov(&tcp_ctask->sendbuf,
+	} else {
+		iscsi_buf_init_iov(&r2t->sendbuf,
 			    (char*)sc->request_buffer + r2t->data_offset,
 			    r2t->data_count);
+		r2t->sg = NULL;
+	}
 }
 
 /**
@@ -503,7 +504,6 @@ iscsi_tcp_hdr_recv(struct iscsi_conn *conn)
 			goto copy_hdr;
 
 		spin_lock(&session->lock);
-		iscsi_tcp_cleanup_ctask(conn, tcp_conn->in.ctask);
 		rc = __iscsi_complete_pdu(conn, hdr, NULL, 0);
 		spin_unlock(&session->lock);
 		break;
@@ -676,15 +676,15 @@ iscsi_tcp_copy(struct iscsi_conn *conn)
 }
 
 static inline void
-partial_sg_digest_update(struct iscsi_tcp_conn *tcp_conn,
-			 struct scatterlist *sg, int offset, int length)
+partial_sg_digest_update(struct crypto_tfm *tfm, struct scatterlist *sg,
+			 int offset, int length)
 {
 	struct scatterlist temp;
 
 	memcpy(&temp, sg, sizeof(struct scatterlist));
 	temp.offset = offset;
 	temp.length = length;
-	crypto_digest_update(tcp_conn->data_rx_tfm, &temp, 1);
+	crypto_digest_update(tfm, &temp, 1);
 }
 
 static void
@@ -751,7 +751,8 @@ static int iscsi_scsi_data_in(struct iscsi_conn *conn)
 							tcp_conn->data_rx_tfm,
 							&sg[i], 1);
 				else
-					partial_sg_digest_update(tcp_conn,
+					partial_sg_digest_update(
+							tcp_conn->data_rx_tfm,
 							&sg[i],
 							sg[i].offset + offset,
 							sg[i].length - offset);
@@ -765,7 +766,8 @@ static int iscsi_scsi_data_in(struct iscsi_conn *conn)
 				/*
 				 * data-in is complete, but buffer not...
 				 */
-				partial_sg_digest_update(tcp_conn, &sg[i],
+				partial_sg_digest_update(tcp_conn->data_rx_tfm,
+						&sg[i],
 						sg[i].offset, sg[i].length-rc);
 			rc = 0;
 			break;
@@ -783,7 +785,6 @@ done:
 			   (long)sc, sc->result, ctask->itt,
 			   tcp_conn->in.hdr->flags);
 		spin_lock(&conn->session->lock);
-		iscsi_tcp_cleanup_ctask(conn, ctask);
 		__iscsi_complete_pdu(conn, tcp_conn->in.hdr, NULL, 0);
 		spin_unlock(&conn->session->lock);
 	}
@@ -803,9 +804,6 @@ iscsi_data_recv(struct iscsi_conn *conn)
 		rc = iscsi_scsi_data_in(conn);
 		break;
 	case ISCSI_OP_SCSI_CMD_RSP:
-		spin_lock(&conn->session->lock);
-		iscsi_tcp_cleanup_ctask(conn, tcp_conn->in.ctask);
-		spin_unlock(&conn->session->lock);
 	case ISCSI_OP_TEXT_RSP:
 	case ISCSI_OP_LOGIN_RSP:
 	case ISCSI_OP_ASYNC_EVENT:
@@ -1188,37 +1186,12 @@ iscsi_sendpage(struct iscsi_conn *conn, struct iscsi_buf *buf,
 
 static inline void
 iscsi_data_digest_init(struct iscsi_tcp_conn *tcp_conn,
-		      struct iscsi_cmd_task *ctask)
+		      struct iscsi_tcp_cmd_task *tcp_ctask)
 {
-	struct iscsi_tcp_cmd_task *tcp_ctask = ctask->dd_data;
-
-	BUG_ON(!tcp_conn->data_tx_tfm);
 	crypto_digest_init(tcp_conn->data_tx_tfm);
 	tcp_ctask->digest_count = 4;
 }
 
-static int
-iscsi_digest_final_send(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask,
-			struct iscsi_buf *buf, uint32_t *digest, int final)
-{
-	struct iscsi_tcp_cmd_task *tcp_ctask = ctask->dd_data;
-	struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
-	int rc = 0;
-	int sent = 0;
-
-	if (final)
-		crypto_digest_final(tcp_conn->data_tx_tfm, (u8*)digest);
-
-	iscsi_buf_init_iov(buf, (char*)digest, 4);
-	rc = iscsi_sendpage(conn, buf, &tcp_ctask->digest_count, &sent);
-	if (rc) {
-		tcp_ctask->datadigest = *digest;
-		tcp_ctask->xmstate |= XMSTATE_DATA_DIGEST;
-	} else
-		tcp_ctask->digest_count = 4;
-	return rc;
-}
-
 /**
  * iscsi_solicit_data_cont - initialize next Data-Out
  * @conn: iscsi connection
@@ -1236,7 +1209,6 @@ static void
 iscsi_solicit_data_cont(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask,
 			struct iscsi_r2t_info *r2t, int left)
 {
-	struct iscsi_tcp_cmd_task *tcp_ctask = ctask->dd_data;
 	struct iscsi_data *hdr;
 	struct scsi_cmnd *sc = ctask->sc;
 	int new_offset;
@@ -1265,14 +1237,30 @@ iscsi_solicit_data_cont(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask,
 	iscsi_buf_init_iov(&r2t->headbuf, (char*)hdr,
 			   sizeof(struct iscsi_hdr));
 
-	if (sc->use_sg && !iscsi_buf_left(&r2t->sendbuf)) {
-		BUG_ON(tcp_ctask->bad_sg == r2t->sg);
+	if (iscsi_buf_left(&r2t->sendbuf))
+		return;
+
+	if (sc->use_sg) {
 		iscsi_buf_init_sg(&r2t->sendbuf, r2t->sg);
 		r2t->sg += 1;
-	} else
-		iscsi_buf_init_iov(&tcp_ctask->sendbuf,
+	} else {
+		iscsi_buf_init_iov(&r2t->sendbuf,
 			    (char*)sc->request_buffer + new_offset,
 			    r2t->data_count);
+		r2t->sg = NULL;
+	}
+}
+
+static void iscsi_set_padding(struct iscsi_tcp_cmd_task *tcp_ctask,
+			      unsigned long len)
+{
+	tcp_ctask->pad_count = len & (ISCSI_PAD_LEN - 1);
+	if (!tcp_ctask->pad_count)
+		return;
+
+	tcp_ctask->pad_count = ISCSI_PAD_LEN - tcp_ctask->pad_count;
+	debug_scsi("write padding %d bytes\n", tcp_ctask->pad_count);
+	tcp_ctask->xmstate |= XMSTATE_W_PAD;
 }
 
 /**
@@ -1300,31 +1288,16 @@ iscsi_tcp_cmd_init(struct iscsi_cmd_task *ctask)
 		if (sc->use_sg) {
 			struct scatterlist *sg = sc->request_buffer;
 
-			iscsi_buf_init_sg(&tcp_ctask->sendbuf,
-					  &sg[tcp_ctask->sg_count++]);
-			tcp_ctask->sg = sg;
+			iscsi_buf_init_sg(&tcp_ctask->sendbuf, sg);
+			tcp_ctask->sg = sg + 1;
 			tcp_ctask->bad_sg = sg + sc->use_sg;
-		} else
+		} else {
 			iscsi_buf_init_iov(&tcp_ctask->sendbuf,
 					   sc->request_buffer,
 					   sc->request_bufflen);
-
-		if (ctask->imm_count)
-			tcp_ctask->xmstate |= XMSTATE_IMM_DATA;
-
-		tcp_ctask->pad_count = ctask->total_length & (ISCSI_PAD_LEN-1);
-		if (tcp_ctask->pad_count) {
-			tcp_ctask->pad_count = ISCSI_PAD_LEN -
-							tcp_ctask->pad_count;
-			debug_scsi("write padding %d bytes\n",
-				   tcp_ctask->pad_count);
-			tcp_ctask->xmstate |= XMSTATE_W_PAD;
+			tcp_ctask->sg = NULL;
+			tcp_ctask->bad_sg = NULL;
 		}
-
-		if (ctask->unsol_count)
-			tcp_ctask->xmstate |= XMSTATE_UNS_HDR |
-						XMSTATE_UNS_INIT;
-
 		debug_scsi("cmd [itt 0x%x total %d imm_data %d "
 			   "unsol count %d, unsol offset %d]\n",
 			   ctask->itt, ctask->total_length, ctask->imm_count,
@@ -1410,8 +1383,8 @@ iscsi_tcp_mtask_xmit(struct iscsi_conn *conn, struct iscsi_mgmt_task *mtask)
 }
 
 static inline int
-handle_xmstate_r_hdr(struct iscsi_conn *conn,
-		     struct iscsi_tcp_cmd_task *tcp_ctask)
+iscsi_send_read_hdr(struct iscsi_conn *conn,
+		    struct iscsi_tcp_cmd_task *tcp_ctask)
 {
 	int rc;
 
@@ -1429,7 +1402,7 @@ handle_xmstate_r_hdr(struct iscsi_conn *conn,
 }
 
 static inline int
-handle_xmstate_w_hdr(struct iscsi_conn *conn,
+iscsi_send_write_hdr(struct iscsi_conn *conn,
 		     struct iscsi_cmd_task *ctask)
 {
 	struct iscsi_tcp_cmd_task *tcp_ctask = ctask->dd_data;
@@ -1440,85 +1413,125 @@ handle_xmstate_w_hdr(struct iscsi_conn *conn,
 		iscsi_hdr_digest(conn, &tcp_ctask->headbuf,
 				 (u8*)tcp_ctask->hdrext);
 	rc = iscsi_sendhdr(conn, &tcp_ctask->headbuf, ctask->imm_count);
-	if (rc)
+	if (rc) {
 		tcp_ctask->xmstate |= XMSTATE_W_HDR;
-	return rc;
+		return rc;
+	}
+
+	if (ctask->imm_count) {
+		tcp_ctask->xmstate |= XMSTATE_IMM_DATA;
+		iscsi_set_padding(tcp_ctask, ctask->imm_count);
+
+		if (ctask->conn->datadgst_en) {
+			iscsi_data_digest_init(ctask->conn->dd_data, tcp_ctask);
+			tcp_ctask->immdigest = 0;
+		}
+	}
+
+	if (ctask->unsol_count)
+		tcp_ctask->xmstate |= XMSTATE_UNS_HDR | XMSTATE_UNS_INIT;
+	return 0;
 }
 
-static inline int
-handle_xmstate_data_digest(struct iscsi_conn *conn,
-			   struct iscsi_cmd_task *ctask)
+static int
+iscsi_send_padding(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask)
 {
 	struct iscsi_tcp_cmd_task *tcp_ctask = ctask->dd_data;
-	int rc;
+	struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
+	int sent = 0, rc;
 
-	tcp_ctask->xmstate &= ~XMSTATE_DATA_DIGEST;
-	debug_tcp("resent data digest 0x%x\n", tcp_ctask->datadigest);
-	rc = iscsi_digest_final_send(conn, ctask, &tcp_ctask->immbuf,
-				    &tcp_ctask->datadigest, 0);
+	if (tcp_ctask->xmstate & XMSTATE_W_PAD) {
+		iscsi_buf_init_iov(&tcp_ctask->sendbuf, (char*)&tcp_ctask->pad,
+				   tcp_ctask->pad_count);
+		if (conn->datadgst_en)
+			crypto_digest_update(tcp_conn->data_tx_tfm,
+					     &tcp_ctask->sendbuf.sg, 1);
+	} else if (!(tcp_ctask->xmstate & XMSTATE_W_RESEND_PAD))
+		return 0;
+
+	tcp_ctask->xmstate &= ~XMSTATE_W_PAD;
+	tcp_ctask->xmstate &= ~XMSTATE_W_RESEND_PAD;
+	debug_scsi("sending %d pad bytes for itt 0x%x\n",
+		   tcp_ctask->pad_count, ctask->itt);
+	rc = iscsi_sendpage(conn, &tcp_ctask->sendbuf, &tcp_ctask->pad_count,
+			   &sent);
 	if (rc) {
-		tcp_ctask->xmstate |= XMSTATE_DATA_DIGEST;
-		debug_tcp("resent data digest 0x%x fail!\n",
-			  tcp_ctask->datadigest);
+		debug_scsi("padding send failed %d\n", rc);
+		tcp_ctask->xmstate |= XMSTATE_W_RESEND_PAD;
 	}
-
 	return rc;
 }
 
-static inline int
-handle_xmstate_imm_data(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask)
+static int
+iscsi_send_digest(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask,
+			struct iscsi_buf *buf, uint32_t *digest)
 {
-	struct iscsi_tcp_cmd_task *tcp_ctask = ctask->dd_data;
-	struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
-	int rc;
+	struct iscsi_tcp_cmd_task *tcp_ctask;
+	struct iscsi_tcp_conn *tcp_conn;
+	int rc, sent = 0;
 
-	BUG_ON(!ctask->imm_count);
-	tcp_ctask->xmstate &= ~XMSTATE_IMM_DATA;
+	if (!conn->datadgst_en)
+		return 0;
 
-	if (conn->datadgst_en) {
-		iscsi_data_digest_init(tcp_conn, ctask);
-		tcp_ctask->immdigest = 0;
-	}
+	tcp_ctask = ctask->dd_data;
+	tcp_conn = conn->dd_data;
 
-	for (;;) {
-		rc = iscsi_sendpage(conn, &tcp_ctask->sendbuf,
-				   &ctask->imm_count, &tcp_ctask->sent);
-		if (rc) {
-			tcp_ctask->xmstate |= XMSTATE_IMM_DATA;
-			if (conn->datadgst_en) {
-				crypto_digest_final(tcp_conn->data_tx_tfm,
-						(u8*)&tcp_ctask->immdigest);
-				debug_tcp("tx imm sendpage fail 0x%x\n",
-					  tcp_ctask->datadigest);
-			}
-			return rc;
-		}
-		if (conn->datadgst_en)
-			crypto_digest_update(tcp_conn->data_tx_tfm,
-					     &tcp_ctask->sendbuf.sg, 1);
+	if (!(tcp_ctask->xmstate & XMSTATE_W_RESEND_DATA_DIGEST)) {
+		crypto_digest_final(tcp_conn->data_tx_tfm, (u8*)digest);
+		iscsi_buf_init_iov(buf, (char*)digest, 4);
+	}
+	tcp_ctask->xmstate &= ~XMSTATE_W_RESEND_DATA_DIGEST;
 
-		if (!ctask->imm_count)
-			break;
-		iscsi_buf_init_sg(&tcp_ctask->sendbuf,
-				  &tcp_ctask->sg[tcp_ctask->sg_count++]);
+	rc = iscsi_sendpage(conn, buf, &tcp_ctask->digest_count, &sent);
+	if (!rc)
+		debug_scsi("sent digest 0x%x for itt 0x%x\n", *digest,
+			  ctask->itt);
+	else {
+		debug_scsi("sending digest 0x%x failed for itt 0x%x!\n",
+			  *digest, ctask->itt);
+		tcp_ctask->xmstate |= XMSTATE_W_RESEND_DATA_DIGEST;
 	}
+	return rc;
+}
 
-	if (conn->datadgst_en && !(tcp_ctask->xmstate & XMSTATE_W_PAD)) {
-		rc = iscsi_digest_final_send(conn, ctask, &tcp_ctask->immbuf,
-				            &tcp_ctask->immdigest, 1);
-		if (rc) {
-			debug_tcp("sending imm digest 0x%x fail!\n",
-				  tcp_ctask->immdigest);
-			return rc;
+static int
+iscsi_send_data(struct iscsi_cmd_task *ctask, struct iscsi_buf *sendbuf,
+		struct scatterlist **sg, int *sent, int *count,
+		struct iscsi_buf *digestbuf, uint32_t *digest)
+{
+	struct iscsi_tcp_cmd_task *tcp_ctask = ctask->dd_data;
+	struct iscsi_conn *conn = ctask->conn;
+	struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
+	int rc, buf_sent, offset;
+
+	while (*count) {
+		buf_sent = 0;
+		offset = sendbuf->sent;
+
+		rc = iscsi_sendpage(conn, sendbuf, count, &buf_sent);
+		*sent = *sent + buf_sent;
+		if (buf_sent && conn->datadgst_en)
+			partial_sg_digest_update(tcp_conn->data_tx_tfm,
+				&sendbuf->sg, sendbuf->sg.offset + offset,
+				buf_sent);
+		if (!iscsi_buf_left(sendbuf) && *sg != tcp_ctask->bad_sg) {
+			iscsi_buf_init_sg(sendbuf, *sg);
+			*sg = *sg + 1;
 		}
-		debug_tcp("sending imm digest 0x%x\n", tcp_ctask->immdigest);
+
+		if (rc)
+			return rc;
 	}
 
-	return 0;
+	rc = iscsi_send_padding(conn, ctask);
+	if (rc)
+		return rc;
+
+	return iscsi_send_digest(conn, ctask, digestbuf, digest);
 }
 
-static inline int
-handle_xmstate_uns_hdr(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask)
+static int
+iscsi_send_unsol_hdr(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask)
 {
 	struct iscsi_tcp_cmd_task *tcp_ctask = ctask->dd_data;
 	struct iscsi_data_task *dtask;
@@ -1526,14 +1539,21 @@ handle_xmstate_uns_hdr(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask)
 
 	tcp_ctask->xmstate |= XMSTATE_UNS_DATA;
 	if (tcp_ctask->xmstate & XMSTATE_UNS_INIT) {
-		dtask = tcp_ctask->dtask = &tcp_ctask->unsol_dtask;
+		dtask = &tcp_ctask->unsol_dtask;
+
 		iscsi_prep_unsolicit_data_pdu(ctask, &dtask->hdr);
 		iscsi_buf_init_iov(&tcp_ctask->headbuf, (char*)&dtask->hdr,
 				   sizeof(struct iscsi_hdr));
 		if (conn->hdrdgst_en)
 			iscsi_hdr_digest(conn, &tcp_ctask->headbuf,
 					(u8*)dtask->hdrext);
+		if (conn->datadgst_en) {
+			iscsi_data_digest_init(ctask->conn->dd_data, tcp_ctask);
+			dtask->digest = 0;
+		}
+
 		tcp_ctask->xmstate &= ~XMSTATE_UNS_INIT;
+		iscsi_set_padding(tcp_ctask, ctask->data_count);
 	}
 
 	rc = iscsi_sendhdr(conn, &tcp_ctask->headbuf, ctask->data_count);
@@ -1548,247 +1568,128 @@ handle_xmstate_uns_hdr(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask)
 	return 0;
 }
 
-static inline int
-handle_xmstate_uns_data(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask)
+static int
+iscsi_send_unsol_pdu(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask)
 {
 	struct iscsi_tcp_cmd_task *tcp_ctask = ctask->dd_data;
-	struct iscsi_data_task *dtask = tcp_ctask->dtask;
-	struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
 	int rc;
 
-	BUG_ON(!ctask->data_count);
-	tcp_ctask->xmstate &= ~XMSTATE_UNS_DATA;
-
-	if (conn->datadgst_en) {
-		iscsi_data_digest_init(tcp_conn, ctask);
-		dtask->digest = 0;
+	if (tcp_ctask->xmstate & XMSTATE_UNS_HDR) {
+		BUG_ON(!ctask->unsol_count);
+		tcp_ctask->xmstate &= ~XMSTATE_UNS_HDR;
+send_hdr:
+		rc = iscsi_send_unsol_hdr(conn, ctask);
+		if (rc)
+			return rc;
 	}
 
-	for (;;) {
+	if (tcp_ctask->xmstate & XMSTATE_UNS_DATA) {
+		struct iscsi_data_task *dtask = &tcp_ctask->unsol_dtask;
 		int start = tcp_ctask->sent;
 
-		rc = iscsi_sendpage(conn, &tcp_ctask->sendbuf,
-				   &ctask->data_count, &tcp_ctask->sent);
-		if (rc) {
-			ctask->unsol_count -= tcp_ctask->sent - start;
-			tcp_ctask->xmstate |= XMSTATE_UNS_DATA;
-			/* will continue with this ctask later.. */
-			if (conn->datadgst_en) {
-				crypto_digest_final(tcp_conn->data_tx_tfm,
-						(u8 *)&dtask->digest);
-				debug_tcp("tx uns data fail 0x%x\n",
-					  dtask->digest);
-			}
-			return rc;
-		}
-
-		BUG_ON(tcp_ctask->sent > ctask->total_length);
+		rc = iscsi_send_data(ctask, &tcp_ctask->sendbuf, &tcp_ctask->sg,
+				     &tcp_ctask->sent, &ctask->data_count,
+				     &dtask->digestbuf, &dtask->digest);
 		ctask->unsol_count -= tcp_ctask->sent - start;
-
+		if (rc)
+			return rc;
+		tcp_ctask->xmstate &= ~XMSTATE_UNS_DATA;
 		/*
-		 * XXX:we may run here with un-initial sendbuf.
-		 * so pass it
+		 * Done with the Data-Out. Next, check if we need
+		 * to send another unsolicited Data-Out.
 		 */
-		if (conn->datadgst_en && tcp_ctask->sent - start > 0)
-			crypto_digest_update(tcp_conn->data_tx_tfm,
-					     &tcp_ctask->sendbuf.sg, 1);
-
-		if (!ctask->data_count)
-			break;
-		iscsi_buf_init_sg(&tcp_ctask->sendbuf,
-				  &tcp_ctask->sg[tcp_ctask->sg_count++]);
-	}
-	BUG_ON(ctask->unsol_count < 0);
-
-	/*
-	 * Done with the Data-Out. Next, check if we need
-	 * to send another unsolicited Data-Out.
-	 */
-	if (ctask->unsol_count) {
-		if (conn->datadgst_en) {
-			rc = iscsi_digest_final_send(conn, ctask,
-						    &dtask->digestbuf,
-						    &dtask->digest, 1);
-			if (rc) {
-				debug_tcp("send uns digest 0x%x fail\n",
-					  dtask->digest);
-				return rc;
-			}
-			debug_tcp("sending uns digest 0x%x, more uns\n",
-				  dtask->digest);
-		}
-		tcp_ctask->xmstate |= XMSTATE_UNS_INIT;
-		return 1;
-	}
-
-	if (conn->datadgst_en && !(tcp_ctask->xmstate & XMSTATE_W_PAD)) {
-		rc = iscsi_digest_final_send(conn, ctask,
-					    &dtask->digestbuf,
-					    &dtask->digest, 1);
-		if (rc) {
-			debug_tcp("send last uns digest 0x%x fail\n",
-				   dtask->digest);
-			return rc;
+		if (ctask->unsol_count) {
+			debug_scsi("sending more uns\n");
+			tcp_ctask->xmstate |= XMSTATE_UNS_INIT;
+			goto send_hdr;
 		}
-		debug_tcp("sending uns digest 0x%x\n",dtask->digest);
 	}
-
 	return 0;
 }
 
-static inline int
-handle_xmstate_sol_data(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask)
+static int iscsi_send_sol_pdu(struct iscsi_conn *conn,
+			      struct iscsi_cmd_task *ctask)
 {
-	struct iscsi_session *session = conn->session;
-	struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
 	struct iscsi_tcp_cmd_task *tcp_ctask = ctask->dd_data;
-	struct iscsi_r2t_info *r2t = tcp_ctask->r2t;
-	struct iscsi_data_task *dtask = &r2t->dtask;
+	struct iscsi_session *session = conn->session;
+	struct iscsi_r2t_info *r2t;
+	struct iscsi_data_task *dtask;
 	int left, rc;
 
-	tcp_ctask->xmstate &= ~XMSTATE_SOL_DATA;
-	tcp_ctask->dtask = dtask;
-
-	if (conn->datadgst_en) {
-		iscsi_data_digest_init(tcp_conn, ctask);
-		dtask->digest = 0;
-	}
-solicit_again:
-	/*
-	 * send Data-Out within this R2T sequence.
-	 */
-	if (!r2t->data_count)
-		goto data_out_done;
-
-	rc = iscsi_sendpage(conn, &r2t->sendbuf, &r2t->data_count, &r2t->sent);
-	if (rc) {
+	if (tcp_ctask->xmstate & XMSTATE_SOL_HDR) {
+		tcp_ctask->xmstate &= ~XMSTATE_SOL_HDR;
 		tcp_ctask->xmstate |= XMSTATE_SOL_DATA;
-		/* will continue with this ctask later.. */
-		if (conn->datadgst_en) {
-			crypto_digest_final(tcp_conn->data_tx_tfm,
-					  (u8 *)&dtask->digest);
-			debug_tcp("r2t data send fail 0x%x\n", dtask->digest);
-		}
-		return rc;
-	}
+		if (!tcp_ctask->r2t)
+			__kfifo_get(tcp_ctask->r2tqueue, (void*)&tcp_ctask->r2t,
+				    sizeof(void*));
+send_hdr:
+		r2t = tcp_ctask->r2t;
+		dtask = &r2t->dtask;
 
-	BUG_ON(r2t->data_count < 0);
-	if (conn->datadgst_en)
-		crypto_digest_update(tcp_conn->data_tx_tfm, &r2t->sendbuf.sg,
-				     1);
-
-	if (r2t->data_count) {
-		BUG_ON(ctask->sc->use_sg == 0);
-		if (!iscsi_buf_left(&r2t->sendbuf)) {
-			BUG_ON(tcp_ctask->bad_sg == r2t->sg);
-			iscsi_buf_init_sg(&r2t->sendbuf, r2t->sg);
-			r2t->sg += 1;
-		}
-		goto solicit_again;
-	}
+		if (conn->hdrdgst_en)
+			iscsi_hdr_digest(conn, &r2t->headbuf,
+					(u8*)dtask->hdrext);
 
-data_out_done:
-	/*
-	 * Done with this Data-Out. Next, check if we have
-	 * to send another Data-Out for this R2T.
-	 */
-	BUG_ON(r2t->data_length - r2t->sent < 0);
-	left = r2t->data_length - r2t->sent;
-	if (left) {
 		if (conn->datadgst_en) {
-			rc = iscsi_digest_final_send(conn, ctask,
-						    &dtask->digestbuf,
-						    &dtask->digest, 1);
-			if (rc) {
-				debug_tcp("send r2t data digest 0x%x"
-					  "fail\n", dtask->digest);
-				return rc;
-			}
-			debug_tcp("r2t data send digest 0x%x\n",
-				  dtask->digest);
+			iscsi_data_digest_init(conn->dd_data, tcp_ctask);
+			dtask->digest = 0;
 		}
-		iscsi_solicit_data_cont(conn, ctask, r2t, left);
-		tcp_ctask->xmstate |= XMSTATE_SOL_DATA;
-		tcp_ctask->xmstate &= ~XMSTATE_SOL_HDR;
-		return 1;
-	}
 
-	/*
-	 * Done with this R2T. Check if there are more
-	 * outstanding R2Ts ready to be processed.
-	 */
-	if (conn->datadgst_en) {
-		rc = iscsi_digest_final_send(conn, ctask, &dtask->digestbuf,
-					    &dtask->digest, 1);
+		rc = iscsi_sendhdr(conn, &r2t->headbuf, r2t->data_count);
 		if (rc) {
-			debug_tcp("send last r2t data digest 0x%x"
-				  "fail\n", dtask->digest);
+			tcp_ctask->xmstate &= ~XMSTATE_SOL_DATA;
+			tcp_ctask->xmstate |= XMSTATE_SOL_HDR;
 			return rc;
 		}
-		debug_tcp("r2t done dout digest 0x%x\n", dtask->digest);
-	}
 
-	tcp_ctask->r2t = NULL;
-	spin_lock_bh(&session->lock);
-	__kfifo_put(tcp_ctask->r2tpool.queue, (void*)&r2t, sizeof(void*));
-	spin_unlock_bh(&session->lock);
-	if (__kfifo_get(tcp_ctask->r2tqueue, (void*)&r2t, sizeof(void*))) {
-		tcp_ctask->r2t = r2t;
-		tcp_ctask->xmstate |= XMSTATE_SOL_DATA;
-		tcp_ctask->xmstate &= ~XMSTATE_SOL_HDR;
-		return 1;
+		iscsi_set_padding(tcp_ctask, r2t->data_count);
+		debug_scsi("sol dout [dsn %d itt 0x%x dlen %d sent %d]\n",
+			r2t->solicit_datasn - 1, ctask->itt, r2t->data_count,
+			r2t->sent);
 	}
 
-	return 0;
-}
+	if (tcp_ctask->xmstate & XMSTATE_SOL_DATA) {
+		r2t = tcp_ctask->r2t;
+		dtask = &r2t->dtask;
 
-static inline int
-handle_xmstate_w_pad(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask)
-{
-	struct iscsi_tcp_cmd_task *tcp_ctask = ctask->dd_data;
-	struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
-	struct iscsi_data_task *dtask = tcp_ctask->dtask;
-	int sent = 0, rc;
+		rc = iscsi_send_data(ctask, &r2t->sendbuf, &r2t->sg,
+				     &r2t->sent, &r2t->data_count,
+				     &dtask->digestbuf, &dtask->digest);
+		if (rc)
+			return rc;
+		tcp_ctask->xmstate &= ~XMSTATE_SOL_DATA;
 
-	tcp_ctask->xmstate &= ~XMSTATE_W_PAD;
-	iscsi_buf_init_iov(&tcp_ctask->sendbuf, (char*)&tcp_ctask->pad,
-			    tcp_ctask->pad_count);
-	rc = iscsi_sendpage(conn, &tcp_ctask->sendbuf, &tcp_ctask->pad_count,
-			   &sent);
-	if (rc) {
-		tcp_ctask->xmstate |= XMSTATE_W_PAD;
-		return rc;
-	}
+		/*
+		 * Done with this Data-Out. Next, check if we have
+		 * to send another Data-Out for this R2T.
+		 */
+		BUG_ON(r2t->data_length - r2t->sent < 0);
+		left = r2t->data_length - r2t->sent;
+		if (left) {
+			iscsi_solicit_data_cont(conn, ctask, r2t, left);
+			tcp_ctask->xmstate |= XMSTATE_SOL_DATA;
+			tcp_ctask->xmstate &= ~XMSTATE_SOL_HDR;
+			goto send_hdr;
+		}
 
-	if (conn->datadgst_en) {
-		crypto_digest_update(tcp_conn->data_tx_tfm,
-				     &tcp_ctask->sendbuf.sg, 1);
-		/* imm data? */
-		if (!dtask) {
-			rc = iscsi_digest_final_send(conn, ctask,
-						    &tcp_ctask->immbuf,
-						    &tcp_ctask->immdigest, 1);
-			if (rc) {
-				debug_tcp("send padding digest 0x%x"
-					  "fail!\n", tcp_ctask->immdigest);
-				return rc;
-			}
-			debug_tcp("done with padding, digest 0x%x\n",
-				  tcp_ctask->datadigest);
-		} else {
-			rc = iscsi_digest_final_send(conn, ctask,
-						    &dtask->digestbuf,
-						    &dtask->digest, 1);
-			if (rc) {
-				debug_tcp("send padding digest 0x%x"
-				          "fail\n", dtask->digest);
-				return rc;
-			}
-			debug_tcp("done with padding, digest 0x%x\n",
-				  dtask->digest);
+		/*
+		 * Done with this R2T. Check if there are more
+		 * outstanding R2Ts ready to be processed.
+		 */
+		spin_lock_bh(&session->lock);
+		tcp_ctask->r2t = NULL;
+		__kfifo_put(tcp_ctask->r2tpool.queue, (void*)&r2t,
+			    sizeof(void*));
+		if (__kfifo_get(tcp_ctask->r2tqueue, (void*)&r2t,
+				sizeof(void*))) {
+			tcp_ctask->r2t = r2t;
+			tcp_ctask->xmstate |= XMSTATE_SOL_DATA;
+			tcp_ctask->xmstate &= ~XMSTATE_SOL_HDR;
+			spin_unlock_bh(&session->lock);
+			goto send_hdr;
 		}
+		spin_unlock_bh(&session->lock);
 	}
-
 	return 0;
 }
 
@@ -1808,85 +1709,30 @@ iscsi_tcp_ctask_xmit(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask)
 		return rc;
 
 	if (tcp_ctask->xmstate & XMSTATE_R_HDR)
-		return handle_xmstate_r_hdr(conn, tcp_ctask);
+		return iscsi_send_read_hdr(conn, tcp_ctask);
 
 	if (tcp_ctask->xmstate & XMSTATE_W_HDR) {
-		rc = handle_xmstate_w_hdr(conn, ctask);
-		if (rc)
-			return rc;
-	}
-
-	/* XXX: for data digest xmit recover */
-	if (tcp_ctask->xmstate & XMSTATE_DATA_DIGEST) {
-		rc = handle_xmstate_data_digest(conn, ctask);
+		rc = iscsi_send_write_hdr(conn, ctask);
 		if (rc)
 			return rc;
 	}
 
 	if (tcp_ctask->xmstate & XMSTATE_IMM_DATA) {
-		rc = handle_xmstate_imm_data(conn, ctask);
+		rc = iscsi_send_data(ctask, &tcp_ctask->sendbuf, &tcp_ctask->sg,
+				     &tcp_ctask->sent, &ctask->imm_count,
+				     &tcp_ctask->immbuf, &tcp_ctask->immdigest);
 		if (rc)
 			return rc;
+		tcp_ctask->xmstate &= ~XMSTATE_IMM_DATA;
 	}
 
-	if (tcp_ctask->xmstate & XMSTATE_UNS_HDR) {
-		BUG_ON(!ctask->unsol_count);
-		tcp_ctask->xmstate &= ~XMSTATE_UNS_HDR;
-unsolicit_head_again:
-		rc = handle_xmstate_uns_hdr(conn, ctask);
-		if (rc)
-			return rc;
-	}
-
-	if (tcp_ctask->xmstate & XMSTATE_UNS_DATA) {
-		rc = handle_xmstate_uns_data(conn, ctask);
-		if (rc == 1)
-			goto unsolicit_head_again;
-		else if (rc)
-			return rc;
-		goto done;
-	}
-
-	if (tcp_ctask->xmstate & XMSTATE_SOL_HDR) {
-		struct iscsi_r2t_info *r2t;
-
-		tcp_ctask->xmstate &= ~XMSTATE_SOL_HDR;
-		tcp_ctask->xmstate |= XMSTATE_SOL_DATA;
-		if (!tcp_ctask->r2t)
-			__kfifo_get(tcp_ctask->r2tqueue, (void*)&tcp_ctask->r2t,
-				    sizeof(void*));
-solicit_head_again:
-		r2t = tcp_ctask->r2t;
-		if (conn->hdrdgst_en)
-			iscsi_hdr_digest(conn, &r2t->headbuf,
-					(u8*)r2t->dtask.hdrext);
-		rc = iscsi_sendhdr(conn, &r2t->headbuf, r2t->data_count);
-		if (rc) {
-			tcp_ctask->xmstate &= ~XMSTATE_SOL_DATA;
-			tcp_ctask->xmstate |= XMSTATE_SOL_HDR;
-			return rc;
-		}
-
-		debug_scsi("sol dout [dsn %d itt 0x%x dlen %d sent %d]\n",
-			r2t->solicit_datasn - 1, ctask->itt, r2t->data_count,
-			r2t->sent);
-	}
-
-	if (tcp_ctask->xmstate & XMSTATE_SOL_DATA) {
-		rc = handle_xmstate_sol_data(conn, ctask);
-		if (rc == 1)
-			goto solicit_head_again;
-		if (rc)
-			return rc;
-	}
+	rc = iscsi_send_unsol_pdu(conn, ctask);
+	if (rc)
+		return rc;
 
-done:
-	/*
-	 * Last thing to check is whether we need to send write
-	 * padding. Note that we check for xmstate equality, not just the bit.
-	 */
-	if (tcp_ctask->xmstate == XMSTATE_W_PAD)
-		rc = handle_xmstate_w_pad(conn, ctask);
+	rc = iscsi_send_sol_pdu(conn, ctask);
+	if (rc)
+		return rc;
 
 	return rc;
 }
diff --git a/drivers/scsi/iscsi_tcp.h b/drivers/scsi/iscsi_tcp.h
index aace8f70dfd7..7e40e94d9fdc 100644
--- a/drivers/scsi/iscsi_tcp.h
+++ b/drivers/scsi/iscsi_tcp.h
@@ -31,23 +31,21 @@
 #define IN_PROGRESS_DDIGEST_RECV	0x3
 
 /* xmit state machine */
-#define	XMSTATE_IDLE			0x0
-#define	XMSTATE_R_HDR			0x1
-#define	XMSTATE_W_HDR			0x2
-#define	XMSTATE_IMM_HDR			0x4
-#define	XMSTATE_IMM_DATA		0x8
-#define	XMSTATE_UNS_INIT		0x10
-#define	XMSTATE_UNS_HDR			0x20
-#define	XMSTATE_UNS_DATA		0x40
-#define	XMSTATE_SOL_HDR			0x80
-#define	XMSTATE_SOL_DATA		0x100
-#define	XMSTATE_W_PAD			0x200
-#define XMSTATE_DATA_DIGEST		0x400
-
-#define ISCSI_CONN_RCVBUF_MIN		262144
-#define ISCSI_CONN_SNDBUF_MIN		262144
+#define XMSTATE_IDLE			0x0
+#define XMSTATE_R_HDR			0x1
+#define XMSTATE_W_HDR			0x2
+#define XMSTATE_IMM_HDR			0x4
+#define XMSTATE_IMM_DATA		0x8
+#define XMSTATE_UNS_INIT		0x10
+#define XMSTATE_UNS_HDR			0x20
+#define XMSTATE_UNS_DATA		0x40
+#define XMSTATE_SOL_HDR			0x80
+#define XMSTATE_SOL_DATA		0x100
+#define XMSTATE_W_PAD			0x200
+#define XMSTATE_W_RESEND_PAD		0x400
+#define XMSTATE_W_RESEND_DATA_DIGEST	0x800
+
 #define ISCSI_PAD_LEN			4
-#define ISCSI_R2T_MAX			16
 #define ISCSI_SG_TABLESIZE		SG_ALL
 #define ISCSI_TCP_MAX_CMD_LEN		16
 
@@ -162,13 +160,10 @@ struct iscsi_tcp_cmd_task {
 	struct iscsi_queue	r2tpool;
 	struct kfifo		*r2tqueue;
 	struct iscsi_r2t_info	**r2ts;
-	uint32_t		datadigest;		/* for recover digest */
 	int			digest_count;
 	uint32_t		immdigest;		/* for imm data */
 	struct iscsi_buf	immbuf;			/* for imm data digest */
-	struct iscsi_data_task	*dtask;		/* data task in progress*/
 	struct iscsi_data_task	unsol_dtask;	/* unsol data task */
-	int			digest_offset;	/* for partial buff digest */
 };
 
 #endif /* ISCSI_H */
diff --git a/drivers/scsi/libiscsi.c b/drivers/scsi/libiscsi.c
index 9584cbc082fe..fb65311c81dd 100644
--- a/drivers/scsi/libiscsi.c
+++ b/drivers/scsi/libiscsi.c
@@ -325,6 +325,30 @@ static void iscsi_tmf_rsp(struct iscsi_conn *conn, struct iscsi_hdr *hdr)
 	wake_up(&conn->ehwait);
 }
 
+static int iscsi_handle_reject(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
+			       char *data, int datalen)
+{
+	struct iscsi_reject *reject = (struct iscsi_reject *)hdr;
+	struct iscsi_hdr rejected_pdu;
+	uint32_t itt;
+
+	conn->exp_statsn = be32_to_cpu(reject->statsn) + 1;
+
+	if (reject->reason == ISCSI_REASON_DATA_DIGEST_ERROR) {
+		if (ntoh24(reject->dlength) > datalen)
+			return ISCSI_ERR_PROTO;
+
+		if (ntoh24(reject->dlength) >= sizeof(struct iscsi_hdr)) {
+			memcpy(&rejected_pdu, data, sizeof(struct iscsi_hdr));
+			itt = rejected_pdu.itt & ISCSI_ITT_MASK;
+			printk(KERN_ERR "itt 0x%x had pdu (op 0x%x) rejected "
+				"due to DataDigest error.\n", itt,
+				rejected_pdu.opcode);
+		}
+	}
+	return 0;
+}
+
 /**
  * __iscsi_complete_pdu - complete pdu
  * @conn: iscsi conn
@@ -436,6 +460,11 @@ int __iscsi_complete_pdu(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
 			break;
 		}
 	} else if (itt == ISCSI_RESERVED_TAG) {
+		rc = iscsi_check_assign_cmdsn(session,
+					     (struct iscsi_nopin*)hdr);
+		if (rc)
+			goto done;
+
 		switch(opcode) {
 		case ISCSI_OP_NOOP_IN:
 			if (datalen) {
@@ -443,11 +472,6 @@ int __iscsi_complete_pdu(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
 				break;
 			}
 
-			rc = iscsi_check_assign_cmdsn(session,
-						 (struct iscsi_nopin*)hdr);
-			if (rc)
-				break;
-
 			if (hdr->ttt == ISCSI_RESERVED_TAG)
 				break;
 
@@ -455,7 +479,8 @@ int __iscsi_complete_pdu(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
 				rc = ISCSI_ERR_CONN_FAILED;
 			break;
 		case ISCSI_OP_REJECT:
-			/* we need sth like iscsi_reject_rsp()*/
+			rc = iscsi_handle_reject(conn, hdr, data, datalen);
+			break;
 		case ISCSI_OP_ASYNC_EVENT:
 			conn->exp_statsn = be32_to_cpu(hdr->statsn) + 1;
 			/* we need sth like iscsi_async_event_rsp() */