Re: [PATCH v4 1/3] PCI: endpoint: Add helper function pci_epf_get_bar_required_size()

[Frank Li]

On Mon, Oct 06, 2025 at 12:43:52PM +0200, Niklas Cassel wrote:
> On Tue, Sep 30, 2025 at 04:39:37PM -0400, Frank Li wrote:
> > Introduce pci_epf_get_bar_required_size() to retrieve the required BAR
> > size and memory size. Prepare for adding support to set an MMIO address to
> > a specific BAR.
> >
> > Use two variables 'aligned_bar_size' and 'aligned_mem_size' to avoid
> > confuse.
>
> 'aligned_bar_size' has been renamed, so this sentence should be updated.
>
>
> (snip)
>
> > @@ -308,7 +327,9 @@ void *pci_epf_alloc_space(struct pci_epf *epf, size_t size, enum pci_barno bar,
> >  	}
> >
> >  	dev = epc->dev.parent;
> > -	space = dma_alloc_coherent(dev, aligned_size, &phys_addr, GFP_KERNEL);
> > +
> > +	space = dma_alloc_coherent(dev, aligned_mem_size,
> > +				   &phys_addr, GFP_KERNEL);
> >  	if (!space) {
> >  		dev_err(dev, "failed to allocate mem space\n");
> >  		return NULL;
> > @@ -317,7 +338,7 @@ void *pci_epf_alloc_space(struct pci_epf *epf, size_t size, enum pci_barno bar,
> >  	epf_bar[bar].phys_addr = phys_addr;
> >  	epf_bar[bar].addr = space;
> >  	epf_bar[bar].size = size;
> > -	epf_bar[bar].aligned_size = aligned_size;
> > +	epf_bar[bar].aligned_size = aligned_mem_size;
>
> I like that this local variable is now named aligned_mem_size
> to more clearly highlight that it is the aligned _memory_ size.
>
> Perhaps you could also rename the struct pci_epf_bar struct member
> 'aligned_size' to 'aligned_mem_size' or perhaps even better,
> 'backing_mem_size' or 'mem_size' ?

How about alloc_mem_size ? which actually used for dma_free() function.

Frank
>
>
> Kind regards,
> Niklas