Re: [PATCH 01/13] driver core: Add iommu_group tracking to struct device
On Fri, May 11, 2012 at 04:55:35PM -0600, Alex Williamson wrote: IOMMU groups allow IOMMU drivers to represent DMA visibility and isolation of devices. Multiple devices may be grouped together for the purposes of DMA. Placing a pointer on struct device enable easy access for things like streaming DMA programming and drivers like VFIO. Signed-off-by: Alex Williamson alex.william...@redhat.com Can't you get this today from the iommu_ops pointer that is on the bus that the device is associated with? Or can devices on a bus have different iommu_group pointers? thanks, greg k-h -- To unsubscribe from this list: send the line unsubscribe kvm in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: [PATCH 01/13] driver core: Add iommu_group tracking to struct device
On Fri, 2012-05-11 at 16:38 -0700, Greg KH wrote: On Fri, May 11, 2012 at 04:55:35PM -0600, Alex Williamson wrote: IOMMU groups allow IOMMU drivers to represent DMA visibility and isolation of devices. Multiple devices may be grouped together for the purposes of DMA. Placing a pointer on struct device enable easy access for things like streaming DMA programming and drivers like VFIO. Signed-off-by: Alex Williamson alex.william...@redhat.com Can't you get this today from the iommu_ops pointer that is on the bus that the device is associated with? Or can devices on a bus have different iommu_group pointers? The latter, each device on a bus might be it's own group. This is often the case on x86 unless PCIe-to-PCI bridges obscure the device visibility. Thanks, Alex -- To unsubscribe from this list: send the line unsubscribe kvm in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: [PATCH 01/13] driver core: Add iommu_group tracking to struct device
On Fri, May 11, 2012 at 05:58:01PM -0600, Alex Williamson wrote: On Fri, 2012-05-11 at 16:38 -0700, Greg KH wrote: On Fri, May 11, 2012 at 04:55:35PM -0600, Alex Williamson wrote: IOMMU groups allow IOMMU drivers to represent DMA visibility and isolation of devices. Multiple devices may be grouped together for the purposes of DMA. Placing a pointer on struct device enable easy access for things like streaming DMA programming and drivers like VFIO. Signed-off-by: Alex Williamson alex.william...@redhat.com Can't you get this today from the iommu_ops pointer that is on the bus that the device is associated with? Or can devices on a bus have different iommu_group pointers? The latter, each device on a bus might be it's own group. This is often the case on x86 unless PCIe-to-PCI bridges obscure the device visibility. Thanks, Ah, ok, then I have no objection to add this to struct device: Acked-by: Greg Kroah-Hartman gre...@linuxfoundation.org -- To unsubscribe from this list: send the line unsubscribe kvm in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
