[Stgt-devel] PATCH 6 of 6 - Implement READ ELEMENT STATUS op code

[Mark Harvey]

On 5/12/07, Ming Zhang <blackmagic02881 at gmail.com> wrote:
> On Sat, 2007-05-12 at 12:36 +1000, Mark Harvey wrote:
> > On 5/12/07, Ming Zhang <blackmagic02881 at gmail.com> wrote:
> > >
> > > On Fri, 2007-05-11 at 13:23 +1000, Mark Harvey wrote:
> > > > SMC module is now useful enough to return a list of 'barcode' media in
> > > > the changer.
> > >
> > > one potential issue for this command is the data can be larger than 1
> > > page if it is a large tl with thousands of elements. pls double check it
> > > is handled.
> >
> > You are correct.
> >
> > Initially, I attempted to estimate at the amount of memory required
> > (based on the number of slots * max record size), however I kept
> > getting a core dump and eventually tracked it down to the following
> > routine in iscsid.c
> >    ======================================
> > static void iscsi_free_cmd_task(struct iscsi_task *task)
> > {
> >         target_cmd_done(&task->scmd);
> >
> >         list_del(&task->c_hlist);
> >         if (task->data) {
> >                 if ((unsigned long) task->data != task->addr)
> >                         free((void *) (unsigned long) task->addr);
> >         }
> >         iscsi_free_task(task);
> > }
> >    ======================================
> >
> > I keept getting a glibc double free error and was not quite sure where
> > to go from here.
>
> if u like, u can get it implemented in the right way and i can help u on
> the crash.

Many thanks.

I will take you up on this offer.

I most likely won't have any 'spare' time to work on this over the
weekend but will forward the patch on ASAP.

BTW: I sort of check for an overflow. I first check to see it the
initiator has allocated more memory then the 'pagesize' and fail the
command. This check will not catch the case where the initiator does
not know how much space to allocate and makes the initial call just to
see what size is returned by the target.


>
>
> >
> > This was to be the subject of another email I had not written as yet,
> > but since you brought it up :)
> >
> > >
> > >
> > > >
> > > > Can't move them about yet. That will be next op code to be implemented.
> > > > _______________________________________________
> > > > Stgt-devel mailing list
> > > > Stgt-devel at lists.berlios.de
> > > > https://lists.berlios.de/mailman/listinfo/stgt-devel
> > >
> > >
>
>