Re: [PATCH v7 06/12] eal: Add pci_uio_alloc_resource()

[Bruce Richardson <bruce.richardson@intel.com>]

On Fri, Jul 03, 2015 at 05:52:11PM +0900, Tetsuya Mukawa wrote:
> On 2015/07/02 19:46, Bruce Richardson wrote:
> > On Tue, Jun 30, 2015 at 05:24:22PM +0900, Tetsuya Mukawa wrote:
> >> From: "Tetsuya.Mukawa" <mukawa@igel.co.jp>
> >>
> >> This patch adds a new function called pci_uio_alloc_resource().
> >> The function hides how to prepare uio resource in linuxapp and bsdapp.
> >> With the function, pci_uio_map_resource() will be more abstracted.
> >>
> >> Signed-off-by: Tetsuya Mukawa <mukawa@igel.co.jp>
> >> ---
> >>  lib/librte_eal/bsdapp/eal/eal_pci.c       | 70 +++++++++++++++++++---------
> >>  lib/librte_eal/linuxapp/eal/eal_pci_uio.c | 77 ++++++++++++++++++++++---------
> >>  2 files changed, 104 insertions(+), 43 deletions(-)
> >>
> >> diff --git a/lib/librte_eal/bsdapp/eal/eal_pci.c b/lib/librte_eal/bsdapp/eal/eal_pci.c
> >> index 06c564f..7d2f8b5 100644
> >> --- a/lib/librte_eal/bsdapp/eal/eal_pci.c
> >> +++ b/lib/librte_eal/bsdapp/eal/eal_pci.c
> >> @@ -189,28 +189,17 @@ pci_uio_map_secondary(struct rte_pci_device *dev)
> >>  	return 1;
> >>  }
> >>  
> >> -/* map the PCI resource of a PCI device in virtual memory */
> >>  static int
> >> -pci_uio_map_resource(struct rte_pci_device *dev)
> >> +pci_uio_alloc_resource(struct rte_pci_device *dev,
> >> +		struct mapped_pci_resource **uio_res)
> > Rather than having to pass in a pointer to a pointer, why not change the
> > return type to be "struct mapped_pci_resource *"? The only return values currently
> > are 0 and -1, so those could map to non-NULL and NULL respectively, for error
> > checking.
> >
> > /Bruce
> 
> It might be difficult to do like above, because pci_uio_alloc_resource()
> returns 0, -1 and 1 as return value so far.
> 
> Original pci_uio_map_resource() returns negative return value as error,
> and positive value as driver not found.
> So I follow this specification while implementing the function.
> 
> Tetsuya

Ok. Keep it as is, so.

/Bruce