[PATCH v2 1/6] bus/cdx: introduce cdx bus

[Gupta, Nipun]

> -----Original Message-----
> From: Yigit, Ferruh <Ferruh.Yigit at amd.com>
> Sent: Friday, April 14, 2023 10:15 PM
> To: Gupta, Nipun <Nipun.Gupta at amd.com>; dev at dpdk.org;
> thomas at monjalon.net; david.marchand at redhat.com
> Cc: Anand, Harpreet <harpreet.anand at amd.com>; Agarwal, Nikhil
> <nikhil.agarwal at amd.com>
> Subject: Re: [PATCH v2 1/6] bus/cdx: introduce cdx bus
> 
> On 4/13/2023 2:26 PM, Nipun Gupta wrote:
> > CDX bus supports multiple type of devices, which can be
> > exposed to user-space via vfio-cdx.
> >
> > vfio-cdx provides the MMIO IO_MEMORY regions as well as the
> > DMA interface for the device (IOMMU).
> >
> > This support aims to enable the DPDK to support the cdx
> > devices in user-space using VFIO interface.
> >
> > Signed-off-by: Nipun Gupta <nipun.gupta at amd.com>
> 
> <...>
> 
> > +/* map a particular resource from a file */
> > +void *
> > +cdx_map_resource(void *requested_addr, int fd, off_t offset, size_t size,
> > +		int additional_flags)
> > +{
> > +	void *mapaddr;
> > +
> > +	/* Map the cdx MMIO memory resource of device */
> > +	mapaddr = rte_mem_map(requested_addr, size,
> > +		RTE_PROT_READ | RTE_PROT_WRITE,
> > +		RTE_MAP_SHARED | additional_flags, fd, offset);
> > +	if (mapaddr == NULL) {
> > +		CDX_BUS_ERR("%s(): cannot map resource(%d, %p, 0x%zx,
> 0x%llx): %s (%p)",
> > +			__func__, fd, requested_addr, size,
> > +			(unsigned long long)offset,
> 
> `checkpatches.sh` complains about '%l' usage, and 'offset' seems defined
> as 'off_t' type.
> 
> As far as I can see 'off_t' is not part of C standard (but posix
> standard), and it is signed, also not clear if 32 bits or 64 bits.
> 
> Since caller of this function already passes parameter with 'uint64_t'
> type, why not change the 'offset' type of this function to 'uint64_t'
> for simplification, and use 'PRIu64' format specifier?

Makes sense. Will update this in next respin.