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 --- include/scsi/iscsi_proto.h | 10 +++++++++- 1 file changed, 9 insertions(+), 1 deletion(-) (limited to 'include/scsi/iscsi_proto.h') diff --git a/include/scsi/iscsi_proto.h b/include/scsi/iscsi_proto.h index 751c81eaa7f3..6947082eee6d 100644 --- a/include/scsi/iscsi_proto.h +++ b/include/scsi/iscsi_proto.h @@ -27,7 +27,7 @@ #define ISCSI_LISTEN_PORT 3260 /* Padding word length */ -#define PAD_WORD_LEN 4 +#define ISCSI_PAD_LEN 4 /* * useful common(control and data pathes) macro @@ -147,6 +147,14 @@ struct iscsi_rlength_ahdr { __be32 read_length; }; +/* Extended CDB AHS */ +struct iscsi_ecdb_ahdr { + __be16 ahslength; /* CDB length - 15, including reserved byte */ + uint8_t ahstype; + uint8_t reserved; + uint8_t ecdb[260 - 16]; /* 4-byte aligned extended CDB spillover */ +}; + /* SCSI Response Header */ struct iscsi_cmd_rsp { uint8_t opcode; -- cgit v1.2.3