1 files changed, 89 insertions, 31 deletions

diff --git a/drivers/scsi/iscsi_tcp.c b/drivers/scsi/iscsi_tcp.c
index e11bce6ab63c..464de780d953 100644
--- a/drivers/scsi/iscsi_tcp.c
+++ b/drivers/scsi/iscsi_tcp.c
@@ -486,7 +486,8 @@ iscsi_tcp_data_recv_prep(struct iscsi_tcp_conn *tcp_conn)
 	struct iscsi_conn *conn = tcp_conn->iscsi_conn;
 	struct hash_desc *rx_hash = NULL;
 
-	if (conn->datadgst_en)
+	if (conn->datadgst_en &
+	    !(conn->session->tt->caps & CAP_DIGEST_OFFLOAD))
 		rx_hash = &tcp_conn->rx_hash;
 
 	iscsi_segment_init_linear(&tcp_conn->in.segment,
@@ -774,7 +775,8 @@ iscsi_tcp_hdr_dissect(struct iscsi_conn *conn, struct iscsi_hdr *hdr)
 			 * we move on to the next scatterlist entry and
 			 * update the digest per-entry.
 			 */
-			if (conn->datadgst_en)
+			if (conn->datadgst_en &&
+			    !(conn->session->tt->caps & CAP_DIGEST_OFFLOAD))
 				rx_hash = &tcp_conn->rx_hash;
 
 			debug_tcp("iscsi_tcp_begin_data_in(%p, offset=%d, "
@@ -902,34 +904,52 @@ iscsi_tcp_hdr_recv_done(struct iscsi_tcp_conn *tcp_conn,
 	 * and go back for more. */
 	if (conn->hdrdgst_en) {
 		if (segment->digest_len == 0) {
+			/*
+			 * Even if we offload the digest processing we
+			 * splice it in so we can increment the skb/segment
+			 * counters in preparation for the data segment.
+			 */
 			iscsi_tcp_segment_splice_digest(segment,
 							segment->recv_digest);
 			return 0;
 		}
-		iscsi_tcp_dgst_header(&tcp_conn->rx_hash, hdr,
-				      segment->total_copied - ISCSI_DIGEST_SIZE,
-				      segment->digest);
 
-		if (!iscsi_tcp_dgst_verify(tcp_conn, segment))
-			return ISCSI_ERR_HDR_DGST;
+		if (!(conn->session->tt->caps & CAP_DIGEST_OFFLOAD)) {
+			iscsi_tcp_dgst_header(&tcp_conn->rx_hash, hdr,
+				segment->total_copied - ISCSI_DIGEST_SIZE,
+				segment->digest);
+
+			if (!iscsi_tcp_dgst_verify(tcp_conn, segment))
+				return ISCSI_ERR_HDR_DGST;
+		}
 	}
 
 	tcp_conn->in.hdr = hdr;
 	return iscsi_tcp_hdr_dissect(conn, hdr);
 }
 
+inline int iscsi_tcp_recv_segment_is_hdr(struct iscsi_tcp_conn *tcp_conn)
+{
+	return tcp_conn->in.segment.done == iscsi_tcp_hdr_recv_done;
+}
+
+enum {
+	ISCSI_TCP_SEGMENT_DONE,		/* curr seg has been processed */
+	ISCSI_TCP_SKB_DONE,		/* skb is out of data */
+	ISCSI_TCP_CONN_ERR,		/* iscsi layer has fired a conn err */
+	ISCSI_TCP_SUSPENDED,		/* conn is suspended */
+};
+
 /**
- * iscsi_tcp_recv - TCP receive in sendfile fashion
- * @rd_desc: read descriptor
- * @skb: socket buffer
+ * iscsi_tcp_recv_skb - Process skb
+ * @conn: iscsi connection
+ * @skb: network buffer with header and/or data segment
  * @offset: offset in skb
- * @len: skb->len - offset
- **/
-static int
-iscsi_tcp_recv(read_descriptor_t *rd_desc, struct sk_buff *skb,
-	       unsigned int offset, size_t len)
+ * @offload: bool indicating if transfer was offloaded
+ */
+int iscsi_tcp_recv_skb(struct iscsi_conn *conn, struct sk_buff *skb,
+		       unsigned int offset, bool offloaded, int *status)
 {
-	struct iscsi_conn *conn = rd_desc->arg.data;
 	struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
 	struct iscsi_segment *segment = &tcp_conn->in.segment;
 	struct skb_seq_state seq;
@@ -940,9 +960,15 @@ iscsi_tcp_recv(read_descriptor_t *rd_desc, struct sk_buff *skb,
 
 	if (unlikely(conn->suspend_rx)) {
 		debug_tcp("conn %d Rx suspended!\n", conn->id);
+		*status = ISCSI_TCP_SUSPENDED;
 		return 0;
 	}
 
+	if (offloaded) {
+		segment->total_copied = segment->total_size;
+		goto segment_done;
+	}
+
 	skb_prepare_seq_read(skb, offset, skb->len, &seq);
 	while (1) {
 		unsigned int avail;
@@ -952,7 +978,9 @@ iscsi_tcp_recv(read_descriptor_t *rd_desc, struct sk_buff *skb,
 		if (avail == 0) {
 			debug_tcp("no more data avail. Consumed %d\n",
 				  consumed);
-			break;
+			*status = ISCSI_TCP_SKB_DONE;
+			skb_abort_seq_read(&seq);
+			goto skb_done;
 		}
 		BUG_ON(segment->copied >= segment->size);
 
@@ -962,25 +990,55 @@ iscsi_tcp_recv(read_descriptor_t *rd_desc, struct sk_buff *skb,
 		consumed += rc;
 
 		if (segment->total_copied >= segment->total_size) {
-			debug_tcp("segment done\n");
-			rc = segment->done(tcp_conn, segment);
-			if (rc != 0) {
-				skb_abort_seq_read(&seq);
-				goto error;
-			}
-
-			/* The done() functions sets up the
-			 * next segment. */
+			skb_abort_seq_read(&seq);
+			goto segment_done;
 		}
 	}
-	skb_abort_seq_read(&seq);
+
+segment_done:
+	*status = ISCSI_TCP_SEGMENT_DONE;
+	debug_tcp("segment done\n");
+	rc = segment->done(tcp_conn, segment);
+	if (rc != 0) {
+		*status = ISCSI_TCP_CONN_ERR;
+		debug_tcp("Error receiving PDU, errno=%d\n", rc);
+		iscsi_conn_failure(conn, rc);
+		return 0;
+	}
+	/* The done() functions sets up the next segment. */
+
+skb_done:
 	conn->rxdata_octets += consumed;
 	return consumed;
+}
+EXPORT_SYMBOL_GPL(iscsi_tcp_recv_skb);
 
-error:
-	debug_tcp("Error receiving PDU, errno=%d\n", rc);
-	iscsi_conn_failure(conn, rc);
-	return 0;
+/**
+ * iscsi_tcp_recv - TCP receive in sendfile fashion
+ * @rd_desc: read descriptor
+ * @skb: socket buffer
+ * @offset: offset in skb
+ * @len: skb->len - offset
+ **/
+static int
+iscsi_tcp_recv(read_descriptor_t *rd_desc, struct sk_buff *skb,
+	       unsigned int offset, size_t len)
+{
+	struct iscsi_conn *conn = rd_desc->arg.data;
+	unsigned int consumed, total_consumed = 0;
+	int status;
+
+	debug_tcp("in %d bytes\n", skb->len - offset);
+
+	do {
+		status = 0;
+		consumed = iscsi_tcp_recv_skb(conn, skb, offset, 0, &status);
+		offset += consumed;
+		total_consumed += consumed;
+	} while (consumed != 0 && status != ISCSI_TCP_SKB_DONE);
+
+	debug_tcp("read %d bytes status %d\n", skb->len - offset, status);
+	return total_consumed;
 }
 
 static void