From db4742dd8f0aa9125b74f9b2516336a75f3d9106 Mon Sep 17 00:00:00 2001 From: Boaz Harrosh Date: Wed, 30 Apr 2008 11:27:26 +0300 Subject: [SCSI] add support for variable length extended commands Add support for variable-length, extended, and vendor specific CDBs to scsi-ml. It is now possible for initiators and ULD's to issue these types of commands. LLDs need not change much. All they need is to raise the .max_cmd_len to the longest command they support (see iscsi patch). - clean-up some code paths that did not expect commands to be larger than 16, and change cmd_len members' type to short as char is not enough. Signed-off-by: Boaz Harrosh Signed-off-by: Benny Halevy Signed-off-by: James Bottomley --- include/scsi/scsi.h | 40 +++++++++++++++++++++++++++++++++------- include/scsi/scsi_cmnd.h | 2 +- include/scsi/scsi_host.h | 8 +++----- 3 files changed, 37 insertions(+), 13 deletions(-) (limited to 'include/scsi') diff --git a/include/scsi/scsi.h b/include/scsi/scsi.h index 1f74bcd603fe..32742c4563de 100644 --- a/include/scsi/scsi.h +++ b/include/scsi/scsi.h @@ -29,13 +29,6 @@ #define SCSI_MAX_SG_CHAIN_SEGMENTS SCSI_MAX_SG_SEGMENTS #endif -/* - * SCSI command lengths - */ - -extern const unsigned char scsi_command_size[8]; -#define COMMAND_SIZE(opcode) scsi_command_size[((opcode) >> 5) & 7] - /* * Special value for scanning to specify scanning or rescanning of all * possible channels, (target) ids, or luns on a given shost. @@ -109,6 +102,7 @@ extern const unsigned char scsi_command_size[8]; #define MODE_SENSE_10 0x5a #define PERSISTENT_RESERVE_IN 0x5e #define PERSISTENT_RESERVE_OUT 0x5f +#define VARIABLE_LENGTH_CMD 0x7f #define REPORT_LUNS 0xa0 #define MAINTENANCE_IN 0xa3 #define MOVE_MEDIUM 0xa5 @@ -135,6 +129,38 @@ extern const unsigned char scsi_command_size[8]; #define ATA_16 0x85 /* 16-byte pass-thru */ #define ATA_12 0xa1 /* 12-byte pass-thru */ +/* + * SCSI command lengths + */ + +#define SCSI_MAX_VARLEN_CDB_SIZE 260 + +/* defined in T10 SCSI Primary Commands-2 (SPC2) */ +struct scsi_varlen_cdb_hdr { + u8 opcode; /* opcode always == VARIABLE_LENGTH_CMD */ + u8 control; + u8 misc[5]; + u8 additional_cdb_length; /* total cdb length - 8 */ + __be16 service_action; + /* service specific data follows */ +}; + +static inline unsigned +scsi_varlen_cdb_length(const void *hdr) +{ + return ((struct scsi_varlen_cdb_hdr *)hdr)->additional_cdb_length + 8; +} + +extern const unsigned char scsi_command_size_tbl[8]; +#define COMMAND_SIZE(opcode) scsi_command_size_tbl[((opcode) >> 5) & 7] + +static inline unsigned +scsi_command_size(const unsigned char *cmnd) +{ + return (cmnd[0] == VARIABLE_LENGTH_CMD) ? + scsi_varlen_cdb_length(cmnd) : COMMAND_SIZE(cmnd[0]); +} + /* * SCSI Architecture Model (SAM) Status codes. Taken from SAM-3 draft * T10/1561-D Revision 4 Draft dated 7th November 2002. diff --git a/include/scsi/scsi_cmnd.h b/include/scsi/scsi_cmnd.h index 7ed883c8e48a..3e46dfae8194 100644 --- a/include/scsi/scsi_cmnd.h +++ b/include/scsi/scsi_cmnd.h @@ -78,7 +78,7 @@ struct scsi_cmnd { int allowed; int timeout_per_command; - unsigned char cmd_len; + unsigned short cmd_len; enum dma_data_direction sc_data_direction; /* These elements define the operation we are about to perform */ diff --git a/include/scsi/scsi_host.h b/include/scsi/scsi_host.h index d967d6dc7a28..1834fdfe82a7 100644 --- a/include/scsi/scsi_host.h +++ b/include/scsi/scsi_host.h @@ -573,13 +573,11 @@ struct Scsi_Host { /* * The maximum length of SCSI commands that this host can accept. * Probably 12 for most host adapters, but could be 16 for others. + * or 260 if the driver supports variable length cdbs. * For drivers that don't set this field, a value of 12 is - * assumed. I am leaving this as a number rather than a bit - * because you never know what subsequent SCSI standards might do - * (i.e. could there be a 20 byte or a 24-byte command a few years - * down the road?). + * assumed. */ - unsigned char max_cmd_len; + unsigned short max_cmd_len; int this_id; int can_queue; -- cgit v1.2.2