varlen extended and vendor-specific cdbs
Subsystems (12)
cover varlen extended and vendor-specific cdbs
This is a proposal for adding support for variable-length, extended, and vendor specific CDBs. It should now cover the entire range of the SCSI standard.
This patchset extends my original submission (over a year old) in that it starts with cleaning up scsi_cmnd, hence the first patch. The other three are similar to the ones submitted before.
This effort is orthogonal to the bidi and scsi_data_buffer effort and can be accepted now. The patchset, however, is presented in this RFC on top of the scsi_data_buffer patches, as they sit in my tree. They can easily be rebased to current scsi-misc. The iscsi patch is on top of the iscsi branch of the iscsi-git-tree.
(Matthew, these patches will conflict with your scsi_cmnd cleanup patches I promise to rebase them before submission)
A complete git-tree based on scsi-misc which includes a complete bidi and varlen work can be fetched from:
- git://git.bhalevy.com/open-osd bidi branch (varlen branch is this work)
- http://www.bhalevy.com/git - has the gitweb GUI
[1/4] Let scsi_cmnd->cmnd use request->cmd buffer
Here I let scsi_cmnd->cmnd point to the space allocated by request->cmd, instead of copying the data. The scsi_cmnd->cmd_len is guaranteed to contain the right length of the command. I have tried to go over every single place in the kernel that uses scsi_cmnd->cmnd and make sure it looks sane. Surprisingly to me, that was not at all bad. I hope I did not miss anything.
I've tested on an x86_64 machine booting from a sata disk and ran the iscsi regression tests as well as my bidi and varlen tests on top of the complete patchset and all tests passed.
[2/4] block layer varlen-cdb
Unlike the scsi approach (see below), I did not want to unify cmd[]/cmd_len and the *varlen_cdb and varlen_cdb_len members of struct request. This is because unlike scsi, block devices do not have a .max_cmd_len parameter to protect them from unexpected large commands.
In the case varlen_cdb and varlen_cdb_len are used the cmd[] buffer is ignored and the cmd_len will be set to zero.
[3/4] scsi: varlen extended and vendor-specific cdbs
Adds support for variable length, extended, and vendor-specific cdbs at the scsi mid-layer.
[4/4] iscsi: extended cdb support
This is on top of the iscsi branch. In the URL above there are the three missing patches for iscsi, that add support for AHSs.
Boaz
PATCH 1/4 Let scsi_cmnd->cmnd use request->cmd[] buffer
- struct scsi_cmnd had a 16 bytes command buffer of its own. This is an unnecessary duplication and copy of request's cmd. It is probably left overs from the time that scsi_cmnd could function without a request attached. So clean that up.
- Once above is done, few places, apart from scsi-ml, needed
adjustments due to changing the data type of scsi_cmnd->cmnd.
- Lots of drivers still use MAX_COMMAND_SIZE. So I have left that #define but equate it to BLK_MAX_CDB. The way I see it and is reflected in the patch below is. MAX_COMMAND_SIZE - means: The longest fixed-length (*) SCSI CDB as per the SCSI standard and is not related to the implementation.
BLK_MAX_CDB. - The allocated space at the request level
(*)fixed-length here means commands that their size can be determined
by their opcode and the CDB does not carry a length specifier, like the VARIABLE_LENGTH_CMD(0x7f) command. This is actually not exactly true and the SCSI standard also defines extended commands and vendor specific commands that can be bigger than 16 bytes. The kernel will support these using the same infrastructure used for VARLEN CDB's. So in effect MAX_COMMAND_SIZE means the maximum size command scsi-ml supports without specifying a cmd_len by ULD's
--- drivers/firewire/fw-sbp2.c | 2 +- drivers/s390/scsi/zfcp_dbf.c | 2 +- drivers/scsi/53c700.c | 6 +++--- drivers/scsi/ibmvscsi/ibmvscsi.c | 2 +- drivers/scsi/scsi_error.c | 14 ++++++++------ drivers/scsi/scsi_lib.c | 5 +++-- drivers/scsi/scsi_tgt_lib.c | 2 ++ drivers/usb/storage/isd200.c | 2 ++ include/scsi/scsi_cmnd.h | 10 +++++++--- include/scsi/scsi_eh.h | 6 ++++-- 10 files changed, 32 insertions(+), 19 deletions(-)
drivers/firewire/fw-sbp2.c +1 -1
@@ -1212,7 +1212,7 @@ static int sbp2_scsi_queuecommand(struct scsi_cmnd *cmd, scsi_done_fn_t done)memset (orb->request.command_block,0 ,sizeof (orb->request.command_block)); -memcpy (orb->request.command_block, cmd->cmnd,COMMAND_SIZE (*cmd->cmnd)); +memcpy (orb->request.command_block, cmd->cmnd, cmd->cmd_len); orb->base.callback = complete_command_orb; orb->base.request_bus =
drivers/s390/scsi/zfcp_dbf.c +1 -1
@@ -730,7 +730,7 @@ _zfcp_scsi_dbf_event_common(const char *tag, const char *tag2, int level, rec->scsi_result = scsi_cmnd->result; rec->scsi_cmnd = (unsigned long )scsi_cmnd; rec->scsi_serial = scsi_cmnd->serial_number; -memcpy (rec->scsi_opcode, &scsi_cmnd->cmnd, +memcpy (rec->scsi_opcode, scsi_cmnd->cmnd,min ((int )scsi_cmnd->cmd_len,ZFCP_DBF_SCSI_OPCODE )); rec->scsi_retries = scsi_cmnd->retries;
drivers/scsi/53c700.c +3 -3
@@ -599,7 +599,7 @@ NCR_700_scsi_done(struct NCR_700_Host_Parameters *hostdata, (struct NCR_700_command_slot *)SCp->host_scribble;dma_unmap_single (hostdata->dev, slot->pCmd, -sizeof (SCp->cmnd),DMA_TO_DEVICE ); +MAX_COMMAND_SIZE ,DMA_TO_DEVICE );if (slot->flags ==NCR_700_FLAG_AUTOSENSE ) {char *cmnd =NCR_700_get_sense_cmnd (SCp->device);#ifdef NCR_700_DEBUG
@@ -1003,7 +1003,7 @@ process_script_interrupt(__u32 dsps, __u32 dsp, struct scsi_cmnd *SCp,* here */ NCR_700_unmap (hostdata, SCp, slot);dma_unmap_single (hostdata->dev, slot->pCmd, -sizeof (SCp->cmnd), +MAX_COMMAND_SIZE ,DMA_TO_DEVICE ); cmnd[0 ] =REQUEST_SENSE ;
@@ -1900,7 +1900,7 @@ NCR_700_queuecommand(struct scsi_cmnd *SCp, void (*done)(struct scsi_cmnd *)) } slot->resume_offset =0 ; slot->pCmd =dma_map_single (hostdata->dev, SCp->cmnd, -sizeof (SCp->cmnd),DMA_TO_DEVICE ); +MAX_COMMAND_SIZE ,DMA_TO_DEVICE );NCR_700_start_command (SCp);return 0 ; }
drivers/scsi/ibmvscsi/ibmvscsi.c +1 -1
@@ -720,7 +720,7 @@ static int ibmvscsi_queuecommand(struct scsi_cmnd *cmnd, srp_cmd = &evt_struct->iu.srp.cmd;memset (srp_cmd,0x00 ,SRP_MAX_IU_LEN ); srp_cmd->opcode =SRP_CMD ; -memcpy (srp_cmd->cdb, cmnd->cmnd,sizeof (cmnd->cmnd)); +memcpy (srp_cmd->cdb, cmnd->cmnd,sizeof (srp_cmd->cdb)); srp_cmd->lun = ((u64 ) lun) <<48 ;if (!map_data_for_srp_cmd (cmnd, evt_struct, srp_cmd, hostdata->dev)) {
drivers/scsi/scsi_error.c +8 -6
@@ -593,7 +593,7 @@ static void scsi_abort_eh_cmnd(struct scsi_cmnd *scmd)* @scmd: SCSI command structure to hijack * @ses: structure to save restore information * @cmnd: CDB to send. Can be NULL if no new cmnd is needed -* @cmnd_size: size in bytes of @cmnd +* @cmnd_size: size in bytes of @cmnd (must be <= BLK_MAX_CDB) * @sense_bytes: size of sense data to copy. or 0 (if != 0 @cmnd is ignored) * * This function is used to save a scsi command information before re-execution
@@ -615,11 +615,13 @@ void scsi_eh_prep_cmnd(struct scsi_cmnd *scmd, struct scsi_eh_save *ses,* command. */ ses->cmd_len = scmd->cmd_len; -memcpy (ses->cmnd, scmd->cmnd,sizeof (scmd->cmnd)); + ses->cmnd = scmd->cmnd; ses->data_direction = scmd->sc_data_direction; ses->sdb = scmd->sdb; ses->result = scmd->result; + scmd->cmnd = ses->eh_cmnd; +memset (scmd->cmnd,0 ,BLK_MAX_CDB );memset (&scmd->sdb,0 ,sizeof (scmd->sdb));if (sense_bytes) {
@@ -630,14 +632,13 @@ void scsi_eh_prep_cmnd(struct scsi_cmnd *scmd, struct scsi_eh_save *ses, scmd->sdb.sglist = &ses->sense_sgl; scmd->sc_data_direction =DMA_FROM_DEVICE ; scmd->sdb.sg_count =1 ; -memset (scmd->cmnd,0 ,sizeof (scmd->cmnd)); scmd->cmnd[0 ] =REQUEST_SENSE ; scmd->cmnd[4 ] = scmd->sdb.length; scmd->cmd_len =COMMAND_SIZE (scmd->cmnd[0 ]); }else { scmd->sc_data_direction =DMA_NONE ;if (cmnd) { -memset (scmd->cmnd,0 ,sizeof (scmd->cmnd)); +BUG_ON (cmnd_size >BLK_MAX_CDB );memcpy (scmd->cmnd, cmnd, cmnd_size); scmd->cmd_len =COMMAND_SIZE (scmd->cmnd[0 ]); }
@@ -670,7 +671,7 @@ void scsi_eh_restore_cmnd(struct scsi_cmnd* scmd, struct scsi_eh_save *ses)* Restore original data */ scmd->cmd_len = ses->cmd_len; -memcpy (scmd->cmnd, ses->cmnd,sizeof (scmd->cmnd)); + scmd->cmnd = ses->cmnd; scmd->sc_data_direction = ses->data_direction; scmd->sdb = ses->sdb; scmd->result = ses->result;
@@ -1689,7 +1690,8 @@ scsi_reset_provider(struct scsi_device *dev, int flag) scmd->request = &req;memset (&scmd->eh_timeout,0 ,sizeof (scmd->eh_timeout)); -memset (&scmd->cmnd,'\0' ,sizeof (scmd->cmnd)); + scmd->cmnd = req.cmd; +memset (scmd->cmnd,0 ,BLK_MAX_CDB ); scmd->scsi_done = scsi_reset_provider_done_command;memset (&scmd->sdb,0 ,sizeof (scmd->sdb));
drivers/scsi/scsi_lib.c +3 -2
@@ -1149,6 +1149,8 @@ static struct scsi_cmnd *scsi_get_cmd_from_req(struct scsi_device *sdev, cmd->tag = req->tag; cmd->request = req; + cmd->cmnd = req->cmd; +return cmd; }
@@ -1186,8 +1188,6 @@ int scsi_setup_blk_pc_cmnd(struct scsi_device *sdev, struct request *req) req->buffer =NULL ; } -BUILD_BUG_ON (sizeof (req->cmd) >sizeof (cmd->cmnd)); -memcpy (cmd->cmnd, req->cmd,sizeof (cmd->cmnd)); cmd->cmd_len = req->cmd_len;if (!req->data_len) cmd->sc_data_direction =DMA_NONE ;
@@ -1224,6 +1224,7 @@ int scsi_setup_fs_cmnd(struct scsi_device *sdev, struct request *req)if (unlikely (!cmd))return BLKPREP_DEFER ; +memset (cmd->cmnd,0 ,BLK_MAX_CDB );return scsi_init_io (cmd); }EXPORT_SYMBOL (scsi_setup_fs_cmnd);
drivers/scsi/scsi_tgt_lib.c +2 -0
@@ -108,6 +108,8 @@ struct scsi_cmnd *scsi_host_get_command(struct Scsi_Host *shost, cmd->jiffies_at_alloc = jiffies; cmd->request = rq; + cmd->cmnd = rq->cmd; + rq->special = cmd; rq->cmd_type =REQ_TYPE_SPECIAL ; rq->cmd_flags |=REQ_TYPE_BLOCK_PC ;
drivers/usb/storage/isd200.c +2 -0
@@ -287,6 +287,7 @@ struct isd200_info {/* maximum number of LUNs supported */ unsigned char MaxLUNs; +unsigned char cmnd[BLK_MAX_CDB ];struct scsi_cmnd srb;struct scatterlist sg; };
@@ -445,6 +446,7 @@ static int isd200_action( struct us_data *us, int action,memset (&ata,0 ,sizeof (ata));memset (&srb_dev,0 ,sizeof (srb_dev)); + srb->cmnd = info->cmnd; srb->device = &srb_dev; ++srb->serial_number;
include/scsi/scsi_cmnd.h +7 -3
@@ -6,12 +6,17 @@#include <linux/types.h> #include <linux/timer.h> #include <linux/scatterlist.h> +#include <linux/blkdev.h> -struct request ;struct scatterlist ;struct Scsi_Host ;struct scsi_device ; +#define MAX_COMMAND_SIZE 16 +#if (MAX_COMMAND_SIZE >BLK_MAX_CDB ) +# error MAX_COMMAND_SIZE can not be bigger than BLK_MAX_CDB +#endif +struct scsi_data_buffer {unsigned length;int resid;
@@ -67,8 +72,7 @@ struct scsi_cmnd {enum dma_data_direction sc_data_direction;/* These elements define the operation we are about to perform */ -#define MAX_COMMAND_SIZE 16 -unsigned char cmnd[MAX_COMMAND_SIZE ]; +unsigned char *cmnd;struct timer_list eh_timeout;/* Used to time out the command. */
include/scsi/scsi_eh.h +4 -2
@@ -68,12 +68,14 @@ extern int scsi_get_sense_info_fld(const u8 * sense_buffer, int sb_len,extern int scsi_reset_provider (struct scsi_device *,int );struct scsi_eh_save { +/* saved state */ int result;enum dma_data_direction data_direction;unsigned char cmd_len; -unsigned char cmnd[MAX_COMMAND_SIZE ]; - +unsigned char *cmnd;struct scsi_data_buffer sdb; +/* new command support */ +unsigned char eh_cmnd[BLK_MAX_CDB ];struct scatterlist sense_sgl; };
Signature · 1 line
1.5.3.1
PATCH 2/4 block layer varlen-cdb
In reply to Boaz Harrosh - add varlen_cdb and varlen_cdb_len to hold a large user cdb if needed. They start as empty. Allocation of buffer must be done by user and held until request execution is done.
--- block/ll_rw_blk.c | 2 ++ include/linux/blkdev.h | 7 ++++++- 2 files changed, 8 insertions(+), 1 deletions(-)
block/ll_rw_blk.c +2 -0
@@ -261,6 +261,8 @@ static void rq_init(struct request_queue *q, struct request *rq) rq->end_io_data =NULL ; rq->completion_data =NULL ; rq->next_rq =NULL ; + rq->varlen_cdb_len =0 ; + rq->varlen_cdb =NULL ; }/**
include/linux/blkdev.h +6 -1
@@ -287,8 +287,13 @@ struct request {/* * when request is used as a packet command carrier */ -unsigned int cmd_len; +unsigned short cmd_len; +unsigned short varlen_cdb_len;/* length of varlen_cdb buffer */ unsigned char cmd[BLK_MAX_CDB ]; +unsigned char *varlen_cdb;/* an optional variable-length cdb. +* points to a user buffer that must be +* valid until end of request +*/ unsigned int data_len;unsigned int sense_len;
Signature · 1 line
1.5.3.1
Re: [PATCH 2/4] block layer varlen-cdb
include/linux/blkdev.h struct request { · line 297
Quoted 13 lines · Boaz Harrosh
include/linux/blkdev.h +6
-1@@ -287,8 +287,13 @@ struct request {/* * when request is used as a packet command carrier */ -unsigned int cmd_len; +unsigned short cmd_len; +unsigned short varlen_cdb_len;/* length of varlen_cdb buffer */ unsigned char cmd[BLK_MAX_CDB ]; +unsigned char *varlen_cdb;/* an optional variable-length cdb. +* points to a user buffer that must be +* valid until end of request +*/
Try this instead:
unsigned int cmd_len;
- unsigned char cmd[BLK_MAX_CDB];
+ unsigned char _cmd[BLK_MAX_CDB];
+ unsigned char *cmd;
Then initialise cmd to the address of _cmd. If you need to override it later (ie patch 3), you can.
Signature · 4 lines
Intel are signing my paycheques ... these opinions are still mine "Bill, look, we understand that you're interested in selling us this operating system, but compare it to ours. We can't possibly take such a retrograde step."
Re: [PATCH 2/4] block layer varlen-cdb
Quoted 22 lines · Matthew Wilcox
include/linux/blkdev.h struct request { · line 297
Quoted 13 lines · Boaz Harrosh
include/linux/blkdev.h +6
-1@@ -287,8 +287,13 @@ struct request {/* * when request is used as a packet command carrier */ -unsigned int cmd_len; +unsigned short cmd_len; +unsigned short varlen_cdb_len;/* length of varlen_cdb buffer */ unsigned char cmd[BLK_MAX_CDB ]; +unsigned char *varlen_cdb;/* an optional variable-length cdb. +* points to a user buffer that must be +* valid until end of request +*/ Try this instead:
(quoted diff) +2
-1unsigned int cmd_len; - unsigned char cmd[BLK_MAX_CDB]; + unsigned char _cmd[BLK_MAX_CDB]; + unsigned char *cmd;
Quoted 3 lines
Then initialise cmd to the address of
_cmd. If you need to override it later (ie patch 3), you can.
I agree this is probably the cleanest implementation but when Boaz and I initially discussed this approach he convinced me that LL block devices assume that req->cmd_len <= BLK_MAX_CDB and it is unsafe at the moment to expose them potentially larger commands.
Re: [PATCH 2/4] block layer varlen-cdb
Quoted 4 lines · Benny Halevy
I agree this is probably the cleanest implementation but when Boaz and I initially discussed this approach he convinced me that LL block devices assume that
req->cmd_len<=BLK_MAX_CDBand it is unsafe at the moment to expose them potentially larger commands.
We'll never submit a command to a low level driver that is longer than the max_cmd_len in the Scsi_Host. So if they've set it higher than they really can deal with, that's an easy bug to fix.
Signature · 4 lines
Intel are signing my paycheques ... these opinions are still mine "Bill, look, we understand that you're interested in selling us this operating system, but compare it to ours. We can't possibly take such a retrograde step."
Re: [PATCH 2/4] block layer varlen-cdb
Quoted 10 lines · Matthew Wilcox
Quoted 4 lines · Benny Halevy
I agree this is probably the cleanest implementation but when Boaz and I initially discussed this approach he convinced me that LL block devices assume that
req->cmd_len<=BLK_MAX_CDBand it is unsafe at the moment to expose them potentially larger commands.We'll never submit a command to a low level driver that is longer than the
max_cmd_lenin theScsi_Host. So if they've set it higher than they really can deal with, that's an easy bug to fix.
This is true for scsi devices, and is what I did in patches 1/4 + 3/4, but for none-scsi, block devices, there is not such a ".max_cmd_len". There are no clients of large commands that are not scsi, so there is no use fixing any of that. The pointer at request is for the scsi case only. (Or can be used by new code for additional private command info)
Boaz
PATCH 3/4 scsi: varlen extended and vendor-specific cdbs
In reply to Boaz HarroshAdd 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 patches).
- 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.
- Add support for varlen_cdb in scsi_execute.
--- block/scsi_ioctl.c | 4 ++-- drivers/scsi/constants.c | 10 +++------- drivers/scsi/scsi.c | 22 +++++++++++----------- drivers/scsi/scsi_lib.c | 25 +++++++++++++++++++++---- include/scsi/scsi.h | 40 +++++++++++++++++++++++++++++++++------- include/scsi/scsi_cmnd.h | 2 +- include/scsi/scsi_host.h | 8 +++----- 7 files changed, 74 insertions(+), 37 deletions(-)
block/scsi_ioctl.c +2 -2
@@ -33,13 +33,13 @@#include <scsi/scsi_cmnd.h> /* 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 <scsi/sg.h>
drivers/scsi/constants.c +3 -7
@@ -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]);
drivers/scsi/scsi.c +11 -11
@@ -79,15 +79,6 @@ static void scsi_done(struct scsi_cmnd *cmd);#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. */
@@ -467,6 +458,7 @@ int scsi_dispatch_cmd(struct scsi_cmnd *cmd)unsigned long flags =0 ;unsigned long timeout;int rtn =0 ; +unsigned cmd_len;/* check if the device is still usable */ if (unlikely (cmd->device->sdev_state ==SDEV_DEL )) {
@@ -548,9 +540,17 @@ 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) { + cmd_len = cmd->cmd_len; +if (!cmd_len) { +BUG_ON (cmd->cmnd[0 ] ==VARIABLE_LENGTH_CMD ); + cmd_len =COMMAND_SIZE ((cmd)->cmnd[0 ]); + } + +if (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);
drivers/scsi/scsi_lib.c +21 -4
@@ -190,8 +190,18 @@ int scsi_execute(struct scsi_device *sdev, const unsigned char *cmd, buffer, bufflen, __GFP_WAIT)) goto out; - req->cmd_len =COMMAND_SIZE (cmd[0 ]); -memcpy (req->cmd, cmd, req->cmd_len); +if (cmd[0 ] ==VARIABLE_LENGTH_CMD ) { + req->varlen_cdb_len =scsi_varlen_cdb_length (cmd); + req->varlen_cdb = (unsigned char *)cmd; + req->cmd_len =0 ; + }else { + req->cmd_len =COMMAND_SIZE (cmd[0 ]); +memcpy (req->cmd, cmd, req->cmd_len); +if (req->cmd_len <MAX_COMMAND_SIZE ) +memset (&req->cmd[req->cmd_len],0 , +MAX_COMMAND_SIZE - req->cmd_len); + } + req->sense = sense; req->sense_len =0 ; req->retries = retries;
@@ -441,7 +451,7 @@ static void scsi_init_cmd_errh(struct scsi_cmnd *cmd)scsi_set_resid (cmd,0 );memset (cmd->sense_buffer,0 ,sizeof cmd->sense_buffer);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)
@@ -1188,7 +1198,14 @@ int scsi_setup_blk_pc_cmnd(struct scsi_device *sdev, struct request *req) req->buffer =NULL ; } - cmd->cmd_len = req->cmd_len; +if (req->varlen_cdb) { + cmd->cmnd = req->varlen_cdb; + cmd->cmd_len = req->varlen_cdb_len; + }else if (req->cmd_len) + cmd->cmd_len = req->cmd_len; +else + cmd->cmd_len =scsi_command_size (cmd->cmnd); +if (!req->data_len) cmd->sc_data_direction =DMA_NONE ;else if (rq_data_dir (req) ==WRITE )
include/scsi/scsi.h +33 -7
@@ -11,13 +11,6 @@#include <linux/types.h> /* -* 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. */
@@ -89,6 +82,7 @@ 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
@@ -116,6 +110,38 @@ extern const unsigned char scsi_command_size[8];#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 { +unsigned char opcode;/* opcode always == VARIABLE_LENGTH_CMD */ +unsigned char control; +unsigned char misc[5 ]; +unsigned char additional_cdb_length;/* total cdb length - 8 */ +unsigned char service_action[2 ]; +/* 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. */
include/scsi/scsi_cmnd.h +1 -1
@@ -68,7 +68,7 @@ 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 */
include/scsi/scsi_host.h +3 -5
@@ -574,13 +574,11 @@ 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;
Signature · 1 line
1.5.3.1
PATCH 4/4 iscsi: extended cdb support
In reply to Boaz HarroshOnce varlen cdbs are supported by the block and scsi-ml layers we can apply this patch to support extended CDBs in iscsi.
--- drivers/scsi/iscsi_tcp.h | 3 +- drivers/scsi/libiscsi.c | 56 ++++++++++++++++++++++++++++++++++++++++---- include/scsi/iscsi_proto.h | 6 +++- 3 files changed, 57 insertions(+), 8 deletions(-)
drivers/scsi/iscsi_tcp.h +2 -1
@@ -23,6 +23,7 @@#define ISCSI_TCP_H #include <scsi/libiscsi.h> +#include <scsi/scsi.h> /* Socket's Receive state machine */ #define IN_PROGRESS_WAIT_HEADER 0x0
@@ -49,7 +50,7 @@#define XMSTATE_SOL_HDR_INIT 0x2000#define ISCSI_SG_TABLESIZE SG_ALL -#define ISCSI_TCP_MAX_CMD_LEN 16 +#define ISCSI_TCP_MAX_CMD_LEN SCSI_MAX_VARLEN_CDB_SIZEstruct crypto_hash ;struct socket ;
drivers/scsi/libiscsi.c +51 -5
74 lines not on this page · raw message
include/scsi/iscsi_proto.h +4 -2
@@ -110,6 +110,7 @@ struct iscsi_ahs_hdr {#define ISCSI_AHSTYPE_CDB 1#define ISCSI_AHSTYPE_RLENGTH 2 +#define ISCSI_CDB_SIZE 16/* iSCSI PDU Header */ struct iscsi_cmd {
@@ -123,7 +124,7 @@ struct iscsi_cmd {__be32 data_length;__be32 cmdsn;__be32 exp_statsn; -uint8_t cdb[16 ];/* SCSI Command Block */ +uint8_t cdb[ISCSI_CDB_SIZE ];/* SCSI Command Block */ /* Additional Data (Command Dependent) */ };
@@ -152,7 +153,8 @@ 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 */ +/* 4-byte aligned extended CDB spillover */ +uint8_t ecdb[260 -ISCSI_CDB_SIZE ]; };/* SCSI Response Header */
Signature · 1 line
1.5.3.1