Re: [dpdk-dev] [PATCH 1/5] pci: fix access to PCI config space in bsd

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

On Fri, May 06, 2016 at 01:13:15PM +0530, Rahul Lakkireddy wrote:
> PCIOCREAD and PCIOCWRITE ioctls to read/write PCI config space fail
> with EPERM due to missing write permission.  Fix by opening /dev/pci/
> with O_RDWR instead.
> 
> Fixes: 632b2d1deeed ("eal: provide functions to access PCI config")
> 
> Signed-off-by: Rahul Lakkireddy <rahul.lakkireddy@chelsio.com>
> Signed-off-by: Kumar Sanghvi <kumaras@chelsio.com>
> ---
>  lib/librte_eal/bsdapp/eal/eal_pci.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/lib/librte_eal/bsdapp/eal/eal_pci.c b/lib/librte_eal/bsdapp/eal/eal_pci.c
> index 2d16d78..82330be 100644
> --- a/lib/librte_eal/bsdapp/eal/eal_pci.c
> +++ b/lib/librte_eal/bsdapp/eal/eal_pci.c
> @@ -422,7 +422,7 @@ int rte_eal_pci_read_config(const struct rte_pci_device *dev,
>  		goto error;
>  	}
>  
> -	fd = open("/dev/pci", O_RDONLY);
> +	fd = open("/dev/pci", O_RDWR);
>  	if (fd < 0) {
>  		RTE_LOG(ERR, EAL, "%s(): error opening /dev/pci\n", __func__);
>  		goto error;
> @@ -466,7 +466,7 @@ int rte_eal_pci_write_config(const struct rte_pci_device *dev,
>  
>  	memcpy(&pi.pi_data, buf, len);
>  
> -	fd = open("/dev/pci", O_RDONLY);
> +	fd = open("/dev/pci", O_RDWR);
>  	if (fd < 0) {
>  		RTE_LOG(ERR, EAL, "%s(): error opening /dev/pci\n", __func__);
>  		goto error;
> -- 
Does the read function as well as the write one need O_RDWR permissions? There
is also an ioctl in rte_eal_pci_scan which operates on a RDONLY file descriptor.
Does that need to be modified also?

/Bruce