[PATCH 3/4] nvme-pci: use max of PRP or SGL for iod size

[Keith Busch]

On Tue, Jul 07, 2020 at 05:58:30PM -0700, Chaitanya Kulkarni wrote:
>  static size_t nvme_pci_iod_alloc_size(struct nvme_dev *dev,
> -		unsigned int size, unsigned int nseg, bool use_sgl)
> +		unsigned int size, unsigned int nseg)
>  {
> -	size_t alloc_size;
> +	size_t npages_sgl = nvme_pci_npages_sgl(nseg);
> +	size_t npages = nvme_npages(size, dev);
> +	size_t alloc_size = sizeof(__le64 *);
>  
> -	if (use_sgl)
> -		alloc_size = sizeof(__le64 *) * nvme_pci_npages_sgl(nseg);
> -	else
> -		alloc_size = sizeof(__le64 *) * nvme_npages(size, dev);
> +	alloc_size *= (npages_sgl > npages ? npages_sgl : npages);

This would look better as:

	alloc_size *= max(npages, npages_sgl);