On 06/07/2010 12:37 PM, Nicholas A. Bellinger wrote: > On Mon, 2010-06-07 at 12:27 +0300, Boaz Harrosh wrote: >> On 06/07/2010 12:02 PM, Nicholas A. Bellinger wrote: >>> On Mon, 2010-06-07 at 11:40 +0300, Boaz Harrosh wrote: >>>> On 06/07/2010 06:50 AM, Nicholas A. Bellinger wrote: >>>>> From: Nicholas Bellinger <nab at linux-iscsi.org> >>>>> >>>>> This patch adds initial support for the block layer implementation of the sg v4 interface >>>>> (BSG) -> STGT with a new struct backingstore_template bsg_bst sharing code with the >>>>> original sg_bst. It adds for new function bs_bsg_cmd_submit() for incoming write I/O >>>>> and bs_bsg_cmd_complete() for polling read I/O using include/linux/bsg.h:struct sg_io_v4. >>>>> >>>>> This patch also splits up bs_sg_open() to support both BSG and SG looking for the >>>>> path "/dev/bsg" in bs_sg_open(), and getting max_queue using SG_GET_COMMAND_Q and >>>>> calling SG_SET_RESERVED_SIZE (following the original bs_sg code in init_sg_device) >>>>> >>>>> Also chk_bsg_device() currently using a hardcoded 254 major as def for BSG does not >>>>> appear in include/linux/major.h just yet.. >>>>> >>>>> So far this has been tested with STGT/iSCSI <-> BSG <-> TCM_Loop SPC-4 iSCSI Target >>>>> Port emulation and is able to mkfs, fsck and mount a filesystem from a TCM/IBLOCK >>>>> Linux LVM kernel level backstore >>>>> >>>>> Signed-off-by: Nicholas A. Bellinger <nab at linux-iscsi.org> >>>>> --- >>>>> usr/bs_sg.c | 178 +++++++++++++++++++++++++++++++++++++++++++++++++++--- >>>>> usr/scsi_cmnd.h | 7 ++ >>>>> 2 files changed, 175 insertions(+), 10 deletions(-) >>>>> >>>>> diff --git a/usr/bs_sg.c b/usr/bs_sg.c >>>>> index 23676ef..d071714 100644 >>>>> --- a/usr/bs_sg.c >>>>> +++ b/usr/bs_sg.c >>> >>> <SNIP> >>> >>>>> + >>>>> +static int bs_bsg_cmd_submit(struct scsi_cmd *cmd) >>>>> +{ >>>>> + struct scsi_lu *dev = cmd->dev; >>>>> + int fd = dev->fd; >>>>> + struct sg_io_v4 *io_hdr = &cmd->cmd_bsg_hdr; >>>>> + int err = 0; >>>>> + /* >>>>> + * Following linux/include/linux/bsg.h >>>>> + */ >>>>> + /* [i] 'Q' to differentiate from v3 */ >>>>> + io_hdr->guard = 'Q'; >>>>> + io_hdr->protocol = BSG_PROTOCOL_SCSI; >>>>> + io_hdr->subprotocol = BSG_SUB_PROTOCOL_SCSI_CMD; >>>>> + io_hdr->request_len = cmd->scb_len; >>>>> + io_hdr->request = (unsigned long )cmd->scb; >>>>> + >>>>> + if (scsi_get_data_dir(cmd) == DATA_WRITE) { >>>> >>>> Why the if? both sides are fully bidi just remove the ifs >>>> and: OUT <= OUT, IN <= IN >>>> >>> >>> Whoops, thanks for pointing this one out (again). Tested with >>> unidirection commands and included into my local tgt.git/pass that I >>> will send along to Tomo-san.. >>> >>> Btw, I still need to sort out BIDI support for TCM_Loop at some point in >>> the not too distant future. What would be a good way to generate BIDI >>> traffic into STGT or a local SCSI LLD..? >> >> scsi_debug has some emulation for XOR commands, does that help? >> > > Great, thanks for the pointer on the LLD side. Is there any userspace > code around that will generate XDWRITEREAD_* CDBs for bulk I/O or do I > need to code this part myself..? > > Best, > > --nab > You could use iscsi as LLD and generate OSD heavy traffic. (With a real osd_tgtd on the end side). But that will need more work, right? what does the TCM_Loop do exactly. Please forgive my laziness, I never took the time to find out. Boaz -- To unsubscribe from this list: send the line "unsubscribe stgt" in the body of a message to majordomo at vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html |