Re: [PATCH 1/2] nvme: keep transport module referenced while head node is open

[Nilay Shroff <nilay@linux.ibm.com>]

On 9/1/26 10:09 PM, Keith Busch wrote:
> On Mon, Aug 31, 2026 at 08:49:54PM +0530, Nilay Shroff wrote:
>> +static inline int nvme_module_get(struct nvme_ns *ns, unsigned int count)
>> +{
>> +	unsigned int i;
>> +
>> +	for (i = 0; i < count; i++) {
>> +		if (!try_module_get(ns->ctrl->ops->module))
>> +			goto out_unwind;
>> +	}
>> +
>> +	return 0;
>> +out_unwind:
>> +	while (i--)
>> +		module_put(ns->ctrl->ops->module);
>> +	return -ENXIO;
>> +}
>> +
>> +static inline void nvme_module_put(struct nvme_ns *ns, unsigned int count)
>> +{
>> +	while (count--)
>> +		module_put(ns->ctrl->ops->module);
>> +}
> 
> Thanks, looks correct to me.
> 
> I don't like the looping though. This could be done in a single
> atomic_sub instead of multiple atomic_dec calls if the module api
> provided something to get/put many references.

Yeah I though of the same however unfortunately module APIs don't
provide something using which we could atomically get/put more than
one references.

Thanks,
--Nilay