From 004d6530f83bee43a55b51bb5960db96e7ae0ffa Mon Sep 17 00:00:00 2001 From: Boaz Harrosh Date: Thu, 13 Dec 2007 12:43:23 -0600 Subject: [SCSI] iscsi_tcp, libiscsi: initial AHS Support at libiscsi generic code - currently code assumes a storage space of pdu header is allocated at llds ctask and is pointed to by iscsi_cmd_task->hdr. Here I add a hdr_max field pertaining to that storage, and an hdr_len that accumulates the current use of the pdu-header. - Add an iscsi_next_hdr() inline which returns the next free space to write new Header at. Also iscsi_next_hdr() is used to retrieve the address at which to write the header-digest. - Add iscsi_add_hdr(length). What the user do is calls iscsi_next_hdr() for address of the new header, than calls iscsi_add_hdr(length) with the size of the new header. iscsi_add_hdr() will check if space is available and update to the new size. length must be padded according to standard. - Add 2 padding inline helpers thanks to Olaf. Current patch does not use them but Following patches will. Also moved definition of ISCSI_PAD_LEN to iscsi_proto.h which had PAD_WORD_LEN that was never used anywhere. - Let iscsi_prep_scsi_cmd_pdu() signal an Error return since now it is possible that it will fail. - I was tired of yet again writing a "this is a digest" comment next to sizeof(__u32) so I defined a new ISCSI_DIGEST_SIZE. Now I don't need any comments. Changed all places that used sizeof(__u32) or "4" in connection to a digest. iscsi_tcp specific code - At struct iscsi_tcp_cmd_task allocate maximum space allowed in standard for all headers following the iscsi_cmd header. and mark it so in iscsi_tcp_session_create() - At iscsi_send_cmd_hdr() retrieve the correct headers size and write header digest at iscsi_next_hdr(). Signed-off-by: Boaz Harrosh Signed-off-by: Olaf Kirch Signed-off-by: Mike Christie Signed-off-by: James Bottomley --- drivers/scsi/iscsi_tcp.c | 16 ++++++++-------- 1 file changed, 8 insertions(+), 8 deletions(-) (limited to 'drivers/scsi/iscsi_tcp.c') diff --git a/drivers/scsi/iscsi_tcp.c b/drivers/scsi/iscsi_tcp.c index fd88777df28b..491845f18710 100644 --- a/drivers/scsi/iscsi_tcp.c +++ b/drivers/scsi/iscsi_tcp.c @@ -113,7 +113,7 @@ iscsi_hdr_digest(struct iscsi_conn *conn, struct iscsi_buf *buf, struct iscsi_tcp_conn *tcp_conn = conn->dd_data; crypto_hash_digest(&tcp_conn->tx_hash, &buf->sg, buf->sg.length, crc); - buf->sg.length += sizeof(u32); + buf->sg.length += ISCSI_DIGEST_SIZE; } /* @@ -220,6 +220,7 @@ static inline int iscsi_tcp_chunk_done(struct iscsi_chunk *chunk) { static unsigned char padbuf[ISCSI_PAD_LEN]; + unsigned int pad; if (chunk->copied < chunk->size) { iscsi_tcp_chunk_map(chunk); @@ -243,10 +244,8 @@ iscsi_tcp_chunk_done(struct iscsi_chunk *chunk) } /* Do we need to handle padding? */ - if (chunk->total_copied & (ISCSI_PAD_LEN-1)) { - unsigned int pad; - - pad = ISCSI_PAD_LEN - (chunk->total_copied & (ISCSI_PAD_LEN-1)); + pad = iscsi_padding(chunk->total_copied); + if (pad != 0) { debug_tcp("consume %d pad bytes\n", pad); chunk->total_size += pad; chunk->size = pad; @@ -1385,11 +1384,11 @@ iscsi_send_cmd_hdr(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask) } iscsi_buf_init_iov(&tcp_ctask->headbuf, (char*)ctask->hdr, - sizeof(struct iscsi_hdr)); + ctask->hdr_len); if (conn->hdrdgst_en) iscsi_hdr_digest(conn, &tcp_ctask->headbuf, - (u8*)tcp_ctask->hdrext); + iscsi_next_hdr(ctask)); tcp_ctask->xmstate &= ~XMSTATE_CMD_HDR_INIT; tcp_ctask->xmstate |= XMSTATE_CMD_HDR_XMIT; } @@ -2176,7 +2175,8 @@ iscsi_tcp_session_create(struct iscsi_transport *iscsit, struct iscsi_cmd_task *ctask = session->cmds[cmd_i]; struct iscsi_tcp_cmd_task *tcp_ctask = ctask->dd_data; - ctask->hdr = &tcp_ctask->hdr; + ctask->hdr = &tcp_ctask->hdr.cmd_hdr; + ctask->hdr_max = sizeof(tcp_ctask->hdr) - ISCSI_DIGEST_SIZE; } for (cmd_i = 0; cmd_i < session->mgmtpool_max; cmd_i++) { -- cgit v1.2.3