[PATCH 09/13] libmultipath: Add PR support

[John Garry]

On 25/02/2026 15:49, Keith Busch wrote:
> On Wed, Feb 25, 2026 at 03:32:21PM +0000, John Garry wrote:
>> +static int mpath_pr_register(struct block_device *bdev, u64 old_key,
>> +			u64 new_key, unsigned int flags)
>> +{
>> +	struct mpath_disk *mpath_disk = dev_get_drvdata(&bdev->bd_device);
>> +	struct mpath_head *mpath_head = mpath_disk->mpath_head;
>> +	struct mpath_device *mpath_device;
>> +	int srcu_idx, ret = -EWOULDBLOCK;
>> +
>> +	srcu_idx = srcu_read_lock(&mpath_head->srcu);
>> +	mpath_device = mpath_find_path(mpath_head);
>> +	if (mpath_device)
>> +		ret = mpath_head->mpdt->pr_ops->pr_register(mpath_device,
>> +				old_key, new_key, flags);
>> +	srcu_read_unlock(&mpath_head->srcu, srcu_idx);
> Instead of having the lower layer define new mp template functions, why
> not use the existing pr_ops from mpath_device->disk->fops->pr_ops?

Yeah, that should be possible and I did use disk->fops elsewhere. We 
would just need to find the per-path bdev. I just wasn't sure if that 
was a preferred style.

cheers