On 6/15/09, Boaz Harrosh <bharrosh@xxxxxxxxxxx> wrote: > On 06/15/2009 05:07 PM, Ramya Desai wrote: > > On 6/15/09, Alan Stern <stern@xxxxxxxxxxxxxxxxxxx> wrote: > >> On Mon, 15 Jun 2009, Boaz Harrosh wrote: > >> > >> > >> If you are using the existing USB mass storage infrastructure then > >> > >> it will not work. This is because all commands are issued from a > >> > >> thread per host, which does a synchronous execution of one command > >> > >> at a time. In fact it does not even have a Q, but a global one cmnd > >> > >> pointer per host. And therefor sets can_queue to 1. > >> > >> > >> > >> Are you using the existing USB infrastructure? > >> > >> > >> > >> > >> > >> Boaz > >> > >> > >> > > I am replacing the default USB mass storage driver with the one I am > >> > > developing. But I am using the default SCSI and USB stack provided by > >> > > Linux. > >> > > > >> > > So is there any another way to make my driver asynchronous? > >> > > > >> > > -RD > >> > > >> > I was afraid so. > >> > > >> > There is a lot of code you will need to change in current USB storage stack > >> > SCSI is built with native support for queuing, but not so USB-storage-stack. > >> > >> > >> Boaz: > >> > >> It looks like you didn't read Ramya's reply to your last message. > >> Ramya isn't keeping the USB storage "stack" -- it is being replaced by > >> a new driver -- so there's no point talking about making changes to it. > >> > >> > >> Alan Stern > >> > >> > > > > I already have an array length of 10 for the bellow members. > > struct scsi_cmnd *srb; /* current srb */ > > unsigned int tag; /* current dCBWTag */ > > > > > That's good > > > > I am maintaining an internal queue for the commands. > > My main problem is , I am not getting the next command in my USB > > storage driver ( My custom) , until the first command is done. > > How can I get the next command, while processing the first command? > > > > -Ramya > > > Post the code you have missed something, I'll have a look > > Boaz > I can not post the code in public because of some limitations I have. But Still I am confused with return status (to SCSI layer) for the command while it is in progress, to get the next command. Is it some thing like PENDING? -RD -- To unsubscribe from this list: send the line "unsubscribe linux-scsi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
