<html> <head> <meta http-equiv="Content-Type" content="text/html; charset=utf-8"> </head> <body smarttemplateinserted="true" text="#000000" bgcolor="#FFFFFF"> <div id="smartTemplate4-template"> After registering e.g. MSI 0 with <tt> __s32 msifd = eventfd(0, 0);</tt> <tt> struct vfio_irq_set *irq_set;</tt><tt> </tt><tt> </tt><tt> irq_set=(struct vfio_irq_set *)malloc(sizeof(struct vfio_irq_set) + sizeof(__s32));</tt><tt> </tt><tt> </tt><tt> irq_set->argsz = sizeof(struct vfio_irq_set) + sizeof(__s32);</tt><tt> </tt><tt> irq_set->index = VFIO_PCI_MSI_IRQ_INDEX;</tt><tt> </tt><tt> irq_set->flags = VFIO_IRQ_SET_DATA_EVENTFD | VFIO_IRQ_SET_ACTION_TRIGGER;</tt><tt> </tt><tt> irq_set->start = 0;</tt><tt> </tt><tt> irq_set->count = 1;</tt><tt> </tt><tt> *(__s32*)&irq_set->data = msifd;</tt><tt> </tt><tt> ioctl(device, VFIO_DEVICE_SET_IRQS, irq_set);</tt> any read by <tt> __u64 value = 0;</tt><tt> </tt><tt> int ret = read(msifd,&value,sizeof(value));</tt><tt> </tt> should acknowledge the MSI, right? Or did I miss something? </div> <div id="smartTemplate4-quoteHeader"> <hr style="color:#62B3FF"> <div style="background-color: #DDDDDD; font-size:10pt">From: <a title="alex.williamson@redhat.com" href="mailto:alex.williamson@redhat.com">Alex Williamson</a> Sent: Wednesday, February 14, 2018 10:18PM To: <a title="oliver.heid@h-next.de" href="mailto:oliver.heid@h-next.de">Heid, Oliver</a> Cc: <a title="vfio-users@redhat.com" href="mailto:vfio-users@redhat.com">Vfio-users</a> Subject: Re: [vfio-users] VFIO for PCIe streaming from/to user space</div> </div> <pre wrap="">On Wed, 14 Feb 2018 22:06:35 +0100 Oliver Heid <a class="moz-txt-link-rfc2396E" href="mailto:oliver.heid@h-next.de"><oliver.heid@h-next.de></a> wrote: </pre> <blockquote type="cite"> <pre wrap="">Regarding the vfio_device_info struct: I get 9 device regions, of which region 0, 2 and 4 seem to be the three BAR regions. Is that so? Always? What do the other regions do? </pre> </blockquote> <pre wrap=""> This is all answered in the API: <a class="moz-txt-link-freetext" href="https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/include/uapi/linux/vfio.h">https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/include/uapi/linux/vfio.h</a> /* * The VFIO-PCI bus driver makes use of the following fixed region and * IRQ index mapping. Unimplemented regions return a size of zero. * Unimplemented IRQ types return a count of zero. */ enum { VFIO_PCI_BAR0_REGION_INDEX, VFIO_PCI_BAR1_REGION_INDEX, VFIO_PCI_BAR2_REGION_INDEX, VFIO_PCI_BAR3_REGION_INDEX, VFIO_PCI_BAR4_REGION_INDEX, VFIO_PCI_BAR5_REGION_INDEX, VFIO_PCI_ROM_REGION_INDEX, VFIO_PCI_CONFIG_REGION_INDEX, /* * Expose VGA regions defined for PCI base class 03, subclass 00. * This includes I/O port ranges 0x3b0 to 0x3bb and 0x3c0 to 0x3df * as well as the MMIO range 0xa0000 to 0xbffff. Each implemented * range is found at it's identity mapped offset from the region * offset, for example 0x3b0 is region_info.offset + 0x3b0. Areas * between described ranges are unimplemented. */ VFIO_PCI_VGA_REGION_INDEX, VFIO_PCI_NUM_REGIONS = 9 /* Fixed user ABI, region indexes >=9 use */ /* device specific cap to define content. */ }; </pre> <blockquote type="cite"> <pre wrap="">And by mmap of PCIe config space you mean mapping the files /sys/bus/pci/devices/0000:xx:yy.z/resource0 ?! </pre> </blockquote> <pre wrap=""> No, use the VFIO_PCI_CONFIG_REGION_INDEX region. </pre> </body> </html>