diff --git a/drivers/scsi/iscsi_tcp.c b/drivers/scsi/iscsi_tcp.c
index e11bce6ab63c7bd5290883d517f556979cedaf2a..464de780d95331aebb80f2a84f809fa4d8d7adb4 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
diff --git a/include/scsi/iscsi_if.h b/include/scsi/iscsi_if.h
index 0c9514de5df7d8f9e514e14f32d8e9d1c2709a80..8e008c96e795fac3d56d212998d3355b62cfef1e 100644
--- a/include/scsi/iscsi_if.h
+++ b/include/scsi/iscsi_if.h
@@ -333,8 +333,9 @@ enum iscsi_host_param {
#define CAP_TEXT_NEGO 0x80
#define CAP_MARKERS 0x100
#define CAP_FW_DB 0x200
-#define CAP_SENDTARGETS_OFFLOAD 0x400
-#define CAP_DATA_PATH_OFFLOAD 0x800
+#define CAP_SENDTARGETS_OFFLOAD 0x400 /* offload discovery process */
+#define CAP_DATA_PATH_OFFLOAD 0x800 /* offload entire IO path */
+#define CAP_DIGEST_OFFLOAD 0x1000 /* offload hdr and data digests */
/*
* These flags describes reason of stop_conn() call