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

From: Matias BjÃrling
Date: Mon Feb 19 2018 - 02:31:40 EST


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.