Re: [PATCH v2 5/6] lightnvm: remove nvm_dev_ops->max_phys_sect

[Matias BjÃrling]

On 02/16/2018 07:48 AM, Javier Gonzalez wrote:
> > On 15 Feb 2018, at 05.11, Matias BjÃrling <mb@xxxxxxxxxxx> wrote:
> >
> > The value of max_phys_sect is always static. Instead of
> > defining it in the nvm_dev_ops structure, declare it as a global
> > value.
> >
> > Signed-off-by: Matias BjÃrling <mb@xxxxxxxxxxx>
> > ---
> > drivers/lightnvm/core.c          | 28 +++++++---------------------
> > drivers/lightnvm/pblk-init.c     |  9 ++++-----
> > drivers/lightnvm/pblk-recovery.c |  8 ++------
> > drivers/nvme/host/lightnvm.c     |  5 +----
> > include/linux/lightnvm.h         |  5 ++---
> > 5 files changed, 16 insertions(+), 39 deletions(-)
>
> The patch looks good, but I have a question. If a target implements the
> scalar interface, then it will not be limited to 64 lbas/ppas and it
> will not make sense to split the bio base don this value. In fact, it
> looks like in time, we will move to a scalar interface in the 2.0 path
> to align with the zoned interface, so this value will be dependent on
> whether the target is using the scalar or vector interface.

Both read/write and vector interface will coexist. I am only removing 
what is hardwired into the specification.

The read/write interface has always been able issue more than 64 LBAs, 
it is instead limited by what the hardware reports its max transfer size 
to be.