Commit 6df19a79 authored by Mike Christie's avatar Mike Christie Committed by James Bottomley
Browse files

[SCSI] libiscsi_tcp: support padding offload



cxgb3i does not offload the processing of the header,
but it will always process the padding. This patch
adds a padding offload flag to detect when the LLD
supports this.

The patch also modifies the header processing so that
we do not try to read/bypass the header dugest in the
skb. cxgb3i will not include it with the header like
with other offload cards.
Signed-off-by: default avatarMike Christie <michaelc@cs.wisc.edu>
Signed-off-by: default avatarJames Bottomley <James.Bottomley@HansenPartnership.com>
parent ae15f801
......@@ -194,7 +194,7 @@ iscsi_sw_tcp_conn_restore_callbacks(struct iscsi_sw_tcp_conn *tcp_sw_conn)
/**
* iscsi_sw_tcp_xmit_segment - transmit segment
* @tcp_sw_conn: the iSCSI TCP connection
* @tcp_conn: the iSCSI TCP connection
* @segment: the buffer to transmnit
*
* This function transmits as much of the buffer as
......@@ -205,14 +205,15 @@ iscsi_sw_tcp_conn_restore_callbacks(struct iscsi_sw_tcp_conn *tcp_sw_conn)
* hash as it goes. When the entire segment has been transmitted,
* it will retrieve the hash value and send it as well.
*/
static int iscsi_sw_tcp_xmit_segment(struct iscsi_sw_tcp_conn *tcp_sw_conn,
static int iscsi_sw_tcp_xmit_segment(struct iscsi_tcp_conn *tcp_conn,
struct iscsi_segment *segment)
{
struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data;
struct socket *sk = tcp_sw_conn->sock;
unsigned int copied = 0;
int r = 0;
while (!iscsi_tcp_segment_done(segment, 0, r)) {
while (!iscsi_tcp_segment_done(tcp_conn, segment, 0, r)) {
struct scatterlist *sg;
unsigned int offset, copy;
int flags = 0;
......@@ -263,7 +264,7 @@ static int iscsi_sw_tcp_xmit(struct iscsi_conn *conn)
int rc = 0;
while (1) {
rc = iscsi_sw_tcp_xmit_segment(tcp_sw_conn, segment);
rc = iscsi_sw_tcp_xmit_segment(tcp_conn, segment);
if (rc < 0) {
rc = ISCSI_ERR_XMIT_FAILED;
goto error;
......
......@@ -159,6 +159,7 @@ iscsi_tcp_segment_splice_digest(struct iscsi_segment *segment, void *digest)
/**
* iscsi_tcp_segment_done - check whether the segment is complete
* @tcp_conn: iscsi tcp connection
* @segment: iscsi segment to check
* @recv: set to one of this is called from the recv path
* @copied: number of bytes copied
......@@ -172,7 +173,8 @@ iscsi_tcp_segment_splice_digest(struct iscsi_segment *segment, void *digest)
*
* This function must be re-entrant.
*/
int iscsi_tcp_segment_done(struct iscsi_segment *segment, int recv,
int iscsi_tcp_segment_done(struct iscsi_tcp_conn *tcp_conn,
struct iscsi_segment *segment, int recv,
unsigned copied)
{
static unsigned char padbuf[ISCSI_PAD_LEN];
......@@ -225,13 +227,15 @@ int iscsi_tcp_segment_done(struct iscsi_segment *segment, int recv,
}
/* Do we need to handle padding? */
pad = iscsi_padding(segment->total_copied);
if (pad != 0) {
debug_tcp("consume %d pad bytes\n", pad);
segment->total_size += pad;
segment->size = pad;
segment->data = padbuf;
return 0;
if (!(tcp_conn->iscsi_conn->session->tt->caps & CAP_PADDING_OFFLOAD)) {
pad = iscsi_padding(segment->total_copied);
if (pad != 0) {
debug_tcp("consume %d pad bytes\n", pad);
segment->total_size += pad;
segment->size = pad;
segment->data = padbuf;
return 0;
}
}
/*
......@@ -273,7 +277,7 @@ iscsi_tcp_segment_recv(struct iscsi_tcp_conn *tcp_conn,
{
unsigned int copy = 0, copied = 0;
while (!iscsi_tcp_segment_done(segment, 1, copy)) {
while (!iscsi_tcp_segment_done(tcp_conn, segment, 1, copy)) {
if (copied == len) {
debug_tcp("iscsi_tcp_segment_recv copied %d bytes\n",
len);
......@@ -794,7 +798,8 @@ iscsi_tcp_hdr_recv_done(struct iscsi_tcp_conn *tcp_conn,
/* We're done processing the header. See if we're doing
* header digests; if so, set up the recv_digest buffer
* and go back for more. */
if (conn->hdrdgst_en) {
if (conn->hdrdgst_en &&
!(conn->session->tt->caps & CAP_DIGEST_OFFLOAD)) {
if (segment->digest_len == 0) {
/*
* Even if we offload the digest processing we
......@@ -806,14 +811,12 @@ iscsi_tcp_hdr_recv_done(struct iscsi_tcp_conn *tcp_conn,
return 0;
}
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);
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 (!iscsi_tcp_dgst_verify(tcp_conn, segment))
return ISCSI_ERR_HDR_DGST;
}
tcp_conn->in.hdr = hdr;
......
......@@ -336,6 +336,8 @@ enum iscsi_host_param {
#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 */
#define CAP_PADDING_OFFLOAD 0x2000 /* offload padding insertion, removal,
and verification */
/*
* These flags describes reason of stop_conn() call
......
......@@ -99,7 +99,8 @@ extern int iscsi_tcp_task_xmit(struct iscsi_task *task);
/* segment helpers */
extern int iscsi_tcp_recv_segment_is_hdr(struct iscsi_tcp_conn *tcp_conn);
extern int iscsi_tcp_segment_done(struct iscsi_segment *segment, int recv,
extern int iscsi_tcp_segment_done(struct iscsi_tcp_conn *tcp_conn,
struct iscsi_segment *segment, int recv,
unsigned copied);
extern void iscsi_tcp_segment_unmap(struct iscsi_segment *segment);
......
Markdown is supported
0% or .
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment