On 2015/10/28 4:38, Jake Oshins wrote: >> -----Original Message----- >> From: Jiang Liu [mailto:jiang.liu@xxxxxxxxxxxxxxx] >> Sent: Tuesday, October 27, 2015 12:11 AM >> To: Jake Oshins <jakeo@xxxxxxxxxxxxx>; gregkh@xxxxxxxxxxxxxxxxxxx; KY >> Srinivasan <kys@xxxxxxxxxxxxx>; linux-kernel@xxxxxxxxxxxxxxx; >> devel@xxxxxxxxxxxxxxxxxxxxxx; olaf@xxxxxxxxx; apw@xxxxxxxxxxxxx; >> vkuznets@xxxxxxxxxx; tglx@xxxxxxxxxxxxx; Haiyang Zhang >> <haiyangz@xxxxxxxxxxxxx>; marc.zyngier@xxxxxxx; >> bhelgaas@xxxxxxxxxx; linux-pci@xxxxxxxxxxxxxxx >> Subject: Re: [PATCH v3 7/7] PCI: hv: New paravirtual PCI front-end for Hyper- >> V VMs >> >> On 2015/10/27 7:15, jakeo@xxxxxxxxxxxxx wrote: >>> From: Jake Oshins <jakeo@xxxxxxxxxxxxx> >>> > (snip) >>> +/** >>> + * hv_pcie_init_irq_domain() - Initialize IRQ domain >>> + * @hbus: The root PCI bus >>> + * >>> + * Return: '0' on success and error value on failure >>> + */ >>> +static int hv_pcie_init_irq_domain(struct hv_pcibus_device *hbus) >>> +{ >>> + hbus->msi_info.chip = &hv_msi_irq_chip; >>> + hbus->msi_info.chip_data = hbus; >>> + hbus->msi_info.ops = &hv_msi_ops; >>> + hbus->msi_info.flags = (MSI_FLAG_USE_DEF_DOM_OPS | >>> + MSI_FLAG_USE_DEF_CHIP_OPS | >> MSI_FLAG_MULTI_PCI_MSI | >>> + MSI_FLAG_PCI_MSIX); >> When interrupt remapping is not supported, x86 vector allocator >> can't support multiple MSI because it can't allocate continuous >> vectors yet. So please confirm whether we could enable >> MSI_FLAG_MULTI_PCI_MSI for HV. >> > > We can actually handle the remapping in the hypervisor. I'll add a comment to that effect. > >>> + hbus->msi_info.handler = handle_edge_irq; >>> + hbus->msi_info.handler_name = "edge"; >>> + hbus->msi_info.data = hbus; >> How about using following pattern so we could avoid exporting >> too many interfaces? >> >> struct irq_domain *parent_domain = NULL; >> hbus->msi_info.chip = &hv_msi_irq_chip; >> hbus->msi_info.ops = &hv_msi_ops; >> // Let arch code to fill in default ops for chip and domain >> x86_setup_default_msi_irqdomian_info(&hbus->msi_info, >> &parent_domain); >> // Override default ops if not applicable >> hbus->irq_domain = pci_msi_create_irq_domain(hbus->fwnode, >> &hbus->msi_info, >> parent_domain); >> > > I understand your point here, but I'm having trouble making it play out. When I look at this, the only functions or structures which are supplied straight from exports (in my proposed patches) are irq_chip_ack_parent(), pci_msi_prepare() and x86_vector_domain. The other exports either already exist for other reasons or they're needed within functions that I need to supply. If you feel strongly that adding a new function to avoid exporting these is the right way to go, I'll do it, but I want to confirm that first. No strong preference here, just feeling that pci_msi_prepare() and x86_vector_domain are arch specific:) And I was hoping that we could find some commonality between this driver and the VMD driver posted at http://lkml.org/lkml/2015/10/27/607 so we could abstract the common part into core. For the VMD driver, it has put the code to create irqdomain into core as vmd_create_irq_domain(). Thanks, Gerry > > Thanks, > Jake Oshins > _______________________________________________ devel mailing list devel@xxxxxxxxxxxxxxxxxxxxxx http://driverdev.linuxdriverproject.org/mailman/listinfo/driverdev-devel
