On 1/24/2024 4:52 PM, Keith Busch wrote:
> On Wed, Jan 24, 2024 at 11:38:41AM +0000, John Garry wrote:
>> diff --git a/drivers/nvme/host/core.c b/drivers/nvme/host/core.c
>> index 5045c84f2516..6a34a5d92088 100644
>> --- a/drivers/nvme/host/core.c
>> +++ b/drivers/nvme/host/core.c
>> @@ -911,6 +911,32 @@ static inline blk_status_t nvme_setup_rw(struct nvme_ns *ns,
>> if (req->cmd_flags & REQ_RAHEAD)
>> dsmgmt |= NVME_RW_DSM_FREQ_PREFETCH;
>>
>> + /*
>> + * Ensure that nothing has been sent which cannot be executed
>> + * atomically.
>> + */
>> + if (req->cmd_flags & REQ_ATOMIC) {
>> + struct nvme_ns_head *head = ns->head;
>> + u32 boundary_bytes = head->atomic_boundary;
>> +
>> + if (blk_rq_bytes(req) > ns->head->atomic_max)
>> + return BLK_STS_IOERR;
>> +
>> + if (boundary_bytes) {
>> + u32 mask = boundary_bytes - 1, imask = ~mask;
>> + u32 start = blk_rq_pos(req) << SECTOR_SHIFT;
>> + u32 end = start + blk_rq_bytes(req);
>> +
>> + if (blk_rq_bytes(req) > boundary_bytes)
>> + return BLK_STS_IOERR;
>> +
>> + if (((start & imask) != (end & imask)) &&
>> + (end & mask)) {
>> + return BLK_STS_IOERR;
>> + }
>> + }
>> + }
>
> Aren't these new fields, atomic_max and atomic_boundary, duplicates of
> the equivalent queue limits? Let's just use the queue limits instead.
>
> And couldn't we generically validate the constraints are not violated in
> submit_bio_noacct() instead of doing that in the low level driver? The
> driver assumes all other requests are already sanity checked, so I don't
> think we should change the responsibility for that just for this flag.
>
does it makes sense to move about code to the helper ? perhaps inline ?
-ck
