From 47cbe50cc8d8e59129311bcdb827e1116e935bde Mon Sep 17 00:00:00 2001 From: Alex Williamson Date: Mon, 2 Mar 2015 11:38:55 -0700 Subject: vfio-pci: Enable device request notification support Linux v4.0-rc1 vfio-pci introduced a new virtual interrupt to allow the kernel to request a device from the user. When signaled, QEMU will by default attmempt to hot-unplug the device. This is a one- shot attempt with the expectation that the kernel will continue to poll for the device if it is not returned. Returning the device when requested is the expected standard model of cooperative usage, but we also add an option option to disable this feature. Initially this opt-out is set as an experimental option because we really should honor kernel requests for the device. Signed-off-by: Alex Williamson --- hw/vfio/pci.c | 100 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 100 insertions(+) (limited to 'hw/vfio') diff --git a/hw/vfio/pci.c b/hw/vfio/pci.c index 3c71de3023..6b80539c1f 100644 --- a/hw/vfio/pci.c +++ b/hw/vfio/pci.c @@ -153,13 +153,17 @@ typedef struct VFIOPCIDevice { VFIOVGA vga; /* 0xa0000, 0x3b0, 0x3c0 */ PCIHostDeviceAddress host; EventNotifier err_notifier; + EventNotifier req_notifier; uint32_t features; #define VFIO_FEATURE_ENABLE_VGA_BIT 0 #define VFIO_FEATURE_ENABLE_VGA (1 << VFIO_FEATURE_ENABLE_VGA_BIT) +#define VFIO_FEATURE_ENABLE_REQ_BIT 1 +#define VFIO_FEATURE_ENABLE_REQ (1 << VFIO_FEATURE_ENABLE_REQ_BIT) int32_t bootindex; uint8_t pm_cap; bool has_vga; bool pci_aer; + bool req_enabled; bool has_flr; bool has_pm_reset; bool rom_read_failed; @@ -3088,6 +3092,7 @@ static int vfio_populate_device(VFIOPCIDevice *vdev) vdev->has_vga = true; } + irq_info.index = VFIO_PCI_ERR_IRQ_INDEX; ret = ioctl(vdev->vbasedev.fd, VFIO_DEVICE_GET_IRQ_INFO, &irq_info); @@ -3223,6 +3228,97 @@ static void vfio_unregister_err_notifier(VFIOPCIDevice *vdev) event_notifier_cleanup(&vdev->err_notifier); } +static void vfio_req_notifier_handler(void *opaque) +{ + VFIOPCIDevice *vdev = opaque; + + if (!event_notifier_test_and_clear(&vdev->req_notifier)) { + return; + } + + qdev_unplug(&vdev->pdev.qdev, NULL); +} + +static void vfio_register_req_notifier(VFIOPCIDevice *vdev) +{ + struct vfio_irq_info irq_info = { .argsz = sizeof(irq_info), + .index = VFIO_PCI_REQ_IRQ_INDEX }; + int argsz; + struct vfio_irq_set *irq_set; + int32_t *pfd; + + if (!(vdev->features & VFIO_FEATURE_ENABLE_REQ)) { + return; + } + + if (ioctl(vdev->vbasedev.fd, + VFIO_DEVICE_GET_IRQ_INFO, &irq_info) < 0 || irq_info.count < 1) { + return; + } + + if (event_notifier_init(&vdev->req_notifier, 0)) { + error_report("vfio: Unable to init event notifier for device request"); + return; + } + + argsz = sizeof(*irq_set) + sizeof(*pfd); + + irq_set = g_malloc0(argsz); + irq_set->argsz = argsz; + irq_set->flags = VFIO_IRQ_SET_DATA_EVENTFD | + VFIO_IRQ_SET_ACTION_TRIGGER; + irq_set->index = VFIO_PCI_REQ_IRQ_INDEX; + irq_set->start = 0; + irq_set->count = 1; + pfd = (int32_t *)&irq_set->data; + + *pfd = event_notifier_get_fd(&vdev->req_notifier); + qemu_set_fd_handler(*pfd, vfio_req_notifier_handler, NULL, vdev); + + if (ioctl(vdev->vbasedev.fd, VFIO_DEVICE_SET_IRQS, irq_set)) { + error_report("vfio: Failed to set up device request notification"); + qemu_set_fd_handler(*pfd, NULL, NULL, vdev); + event_notifier_cleanup(&vdev->req_notifier); + } else { + vdev->req_enabled = true; + } + + g_free(irq_set); +} + +static void vfio_unregister_req_notifier(VFIOPCIDevice *vdev) +{ + int argsz; + struct vfio_irq_set *irq_set; + int32_t *pfd; + + if (!vdev->req_enabled) { + return; + } + + argsz = sizeof(*irq_set) + sizeof(*pfd); + + irq_set = g_malloc0(argsz); + irq_set->argsz = argsz; + irq_set->flags = VFIO_IRQ_SET_DATA_EVENTFD | + VFIO_IRQ_SET_ACTION_TRIGGER; + irq_set->index = VFIO_PCI_REQ_IRQ_INDEX; + irq_set->start = 0; + irq_set->count = 1; + pfd = (int32_t *)&irq_set->data; + *pfd = -1; + + if (ioctl(vdev->vbasedev.fd, VFIO_DEVICE_SET_IRQS, irq_set)) { + error_report("vfio: Failed to de-assign device request fd: %m"); + } + g_free(irq_set); + qemu_set_fd_handler(event_notifier_get_fd(&vdev->req_notifier), + NULL, NULL, vdev); + event_notifier_cleanup(&vdev->req_notifier); + + vdev->req_enabled = false; +} + static int vfio_initfn(PCIDevice *pdev) { VFIOPCIDevice *vdev = DO_UPCAST(VFIOPCIDevice, pdev, pdev); @@ -3370,6 +3466,7 @@ static int vfio_initfn(PCIDevice *pdev) } vfio_register_err_notifier(vdev); + vfio_register_req_notifier(vdev); return 0; @@ -3397,6 +3494,7 @@ static void vfio_exitfn(PCIDevice *pdev) { VFIOPCIDevice *vdev = DO_UPCAST(VFIOPCIDevice, pdev, pdev); + vfio_unregister_req_notifier(vdev); vfio_unregister_err_notifier(vdev); pci_device_set_intx_routing_notifier(&vdev->pdev, NULL); vfio_disable_interrupts(vdev); @@ -3455,6 +3553,8 @@ static Property vfio_pci_dev_properties[] = { intx.mmap_timeout, 1100), DEFINE_PROP_BIT("x-vga", VFIOPCIDevice, features, VFIO_FEATURE_ENABLE_VGA_BIT, false), + DEFINE_PROP_BIT("x-req", VFIOPCIDevice, features, + VFIO_FEATURE_ENABLE_REQ_BIT, true), DEFINE_PROP_INT32("bootindex", VFIOPCIDevice, bootindex, -1), DEFINE_PROP_BOOL("x-mmap", VFIOPCIDevice, vbasedev.allow_mmap, true), /* -- cgit v1.2.3