From db4742dd8f0aa9125b74f9b2516336a75f3d9106 Mon Sep 17 00:00:00 2001 From: Boaz Harrosh Date: Wed, 30 Apr 2008 11:27:26 +0300 Subject: [PATCH] [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 --- block/scsi_ioctl.c | 5 ++--- drivers/scsi/constants.c | 10 +++------- drivers/scsi/scsi.c | 15 ++++----------- drivers/scsi/scsi_lib.c | 2 +- include/scsi/scsi.h | 40 +++++++++++++++++++++++++++++++++------- include/scsi/scsi_cmnd.h | 2 +- include/scsi/scsi_host.h | 8 +++----- 7 files changed, 47 insertions(+), 35 deletions(-) diff --git a/block/scsi_ioctl.c b/block/scsi_ioctl.c index a2c3a936ebf9..aaf07e413ffd 100644 --- a/block/scsi_ioctl.c +++ b/block/scsi_ioctl.c @@ -33,13 +33,12 @@ #include /* Command group 3 is reserved and should never be used. */ -const unsigned char scsi_command_size[8] = +const unsigned char scsi_command_size_tbl[8] = { 6, 10, 10, 12, 16, 12, 10, 10 }; - -EXPORT_SYMBOL(scsi_command_size); +EXPORT_SYMBOL(scsi_command_size_tbl); #include diff --git a/drivers/scsi/constants.c b/drivers/scsi/constants.c index 403a7f2d8f9b..9785d7384199 100644 --- a/drivers/scsi/constants.c +++ b/drivers/scsi/constants.c @@ -28,7 +28,6 @@ #define SERVICE_ACTION_OUT_12 0xa9 #define SERVICE_ACTION_IN_16 0x9e #define SERVICE_ACTION_OUT_16 0x9f -#define VARIABLE_LENGTH_CMD 0x7f @@ -210,7 +209,7 @@ static void print_opcode_name(unsigned char * cdbp, int cdb_len) cdb0 = cdbp[0]; switch(cdb0) { case VARIABLE_LENGTH_CMD: - len = cdbp[7] + 8; + len = scsi_varlen_cdb_length(cdbp); if (len < 10) { printk("short variable length command, " "len=%d ext_len=%d", len, cdb_len); @@ -300,7 +299,7 @@ static void print_opcode_name(unsigned char * cdbp, int cdb_len) cdb0 = cdbp[0]; switch(cdb0) { case VARIABLE_LENGTH_CMD: - len = cdbp[7] + 8; + len = scsi_varlen_cdb_length(cdbp); if (len < 10) { printk("short opcode=0x%x command, len=%d " "ext_len=%d", cdb0, len, cdb_len); @@ -335,10 +334,7 @@ void __scsi_print_command(unsigned char *cdb) int k, len; print_opcode_name(cdb, 0); - if (VARIABLE_LENGTH_CMD == cdb[0]) - len = cdb[7] + 8; - else - len = COMMAND_SIZE(cdb[0]); + len = scsi_command_size(cdb); /* print out all bytes in cdb */ for (k = 0; k < len; ++k) printk(" %02x", cdb[k]); diff --git a/drivers/scsi/scsi.c b/drivers/scsi/scsi.c index 749c9c7fc2e1..110e776d1a07 100644 --- a/drivers/scsi/scsi.c +++ b/drivers/scsi/scsi.c @@ -78,15 +78,6 @@ static void scsi_done(struct scsi_cmnd *cmd); /* Do not call reset on error if we just did a reset within 15 sec. */ #define MIN_RESET_PERIOD (15*HZ) -/* - * Macro to determine the size of SCSI command. This macro takes vendor - * unique commands into account. SCSI commands in groups 6 and 7 are - * vendor unique and we will depend upon the command length being - * supplied correctly in cmd_len. - */ -#define CDB_SIZE(cmd) (((((cmd)->cmnd[0] >> 5) & 7) < 6) ? \ - COMMAND_SIZE((cmd)->cmnd[0]) : (cmd)->cmd_len) - /* * Note - the initial logging level can be set here to log events at boot time. * After the system is up, you may enable logging via the /proc interface. @@ -709,9 +700,11 @@ int scsi_dispatch_cmd(struct scsi_cmnd *cmd) * Before we queue this command, check if the command * length exceeds what the host adapter can handle. */ - if (CDB_SIZE(cmd) > cmd->device->host->max_cmd_len) { + if (cmd->cmd_len > cmd->device->host->max_cmd_len) { SCSI_LOG_MLQUEUE(3, - printk("queuecommand : command too long.\n")); + printk("queuecommand : command too long. " + "cdb_size=%d host->max_cmd_len=%d\n", + cmd->cmd_len, cmd->device->host->max_cmd_len)); cmd->result = (DID_ABORT << 16); scsi_done(cmd); diff --git a/drivers/scsi/scsi_lib.c b/drivers/scsi/scsi_lib.c index 325270b520e1..ba7e8ad76d04 100644 --- a/drivers/scsi/scsi_lib.c +++ b/drivers/scsi/scsi_lib.c @@ -445,7 +445,7 @@ static void scsi_init_cmd_errh(struct scsi_cmnd *cmd) scsi_set_resid(cmd, 0); memset(cmd->sense_buffer, 0, SCSI_SENSE_BUFFERSIZE); if (cmd->cmd_len == 0) - cmd->cmd_len = COMMAND_SIZE(cmd->cmnd[0]); + cmd->cmd_len = scsi_command_size(cmd->cmnd); } void scsi_device_unbusy(struct scsi_device *sdev) 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; -- 2.20.1