[dpdk-dev] [PATCH v2 1/2] eal/pci: introduce a PCI driver flag

[Ferruh Yigit]

On 6/8/2017 12:44 PM, Jerin Jacob wrote:
> Some ethdev devices like nicvf thunderx PMD need special treatment for
> Secondary queue set(SQS) PCIe VF devices, where, it expects to not unmap
> or free the memory without registering the ethdev subsystem.
> 
> Introducing a new RTE_PCI_DRV_KEEP_MAPPED_RES
> PCI driver flag to request PCI subsystem to not unmap the mapped PCI
> resources(PCI BAR address) if unsupported device detected.
> 
> Signed-off-by: Jerin Jacob <jerin.jacob at caviumnetworks.com>

<...>

> @@ -235,6 +240,7 @@ rte_pci_probe_one_driver(struct rte_pci_driver *dr,
>  static int
>  rte_pci_detach_dev(struct rte_pci_device *dev)
>  {
> +	int ret = 0;
>  	struct rte_pci_addr *loc;
>  	struct rte_pci_driver *dr;
>  
> @@ -251,13 +257,18 @@ rte_pci_detach_dev(struct rte_pci_device *dev)
>  	RTE_LOG(DEBUG, EAL, "  remove driver: %x:%x %s\n", dev->id.vendor_id,
>  			dev->id.device_id, dr->driver.name);
>  
> -	if (dr->remove && (dr->remove(dev) < 0))
> -		return -1;	/* negative value is an error */
> +	if (dr->remove) {
> +		ret = dr->remove(dev);
> +		if (ret < 0)
> +			return -1; /* negative value is an error */
> +	}
>  
>  	/* clear driver structure */
>  	dev->driver = NULL;
>  
> -	if (dr->drv_flags & RTE_PCI_DRV_NEED_MAPPING)
> +	if ((dr->drv_flags & RTE_PCI_DRV_NEED_MAPPING) &&
> +	/* Don't unmap if dev is unsupported and it needs mapped resources */
> +		!(ret > 0 && (dr->drv_flags & RTE_PCI_DRV_KEEP_MAPPED_RES)))

Why it is required to keep mapping during detach?

>  		/* unmap resources for devices that use igb_uio */
>  		rte_pci_unmap_device(dev);
>  

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