On Tue, 11 Aug 2020 19:28:45 +0200 Philippe Mathieu-Daudé <phi...@redhat.com> wrote:
> Add a new 'index' argument to qemu_vfio_pci_init_irq() to be able > to initialize other IRQs than IRQ #0. Adapt the single user of this > API in nvme_init(). This is actually addressing the what the vfio uAPI refers to as the subindex, the index is the interrupt type, ex. MSI-X. > > Signed-off-by: Philippe Mathieu-Daudé <phi...@redhat.com> > --- > include/qemu/vfio-helpers.h | 2 +- > block/nvme.c | 2 +- > util/vfio-helpers.c | 12 +++++++++--- > 3 files changed, 11 insertions(+), 5 deletions(-) > > diff --git a/include/qemu/vfio-helpers.h b/include/qemu/vfio-helpers.h > index 1f057c2b9e..ff63e75096 100644 > --- a/include/qemu/vfio-helpers.h > +++ b/include/qemu/vfio-helpers.h > @@ -27,6 +27,6 @@ void *qemu_vfio_pci_map_bar(QEMUVFIOState *s, int index, > void qemu_vfio_pci_unmap_bar(QEMUVFIOState *s, int index, void *bar, > uint64_t offset, uint64_t size); > int qemu_vfio_pci_init_irq(QEMUVFIOState *s, EventNotifier *e, > - int irq_type, Error **errp); > + int irq_type, unsigned index, Error **errp); > > #endif > diff --git a/block/nvme.c b/block/nvme.c > index 374e268915..2b3986b66d 100644 > --- a/block/nvme.c > +++ b/block/nvme.c > @@ -757,7 +757,7 @@ static int nvme_init(BlockDriverState *bs, const char > *device, int namespace, > } > > ret = qemu_vfio_pci_init_irq(s->vfio, &s->irq_notifier, > - VFIO_PCI_MSIX_IRQ_INDEX, errp); > + VFIO_PCI_MSIX_IRQ_INDEX, 0, errp); > if (ret) { > goto out; > } > diff --git a/util/vfio-helpers.c b/util/vfio-helpers.c > index 3ad7e6be52..ba9a869364 100644 > --- a/util/vfio-helpers.c > +++ b/util/vfio-helpers.c > @@ -173,10 +173,11 @@ void qemu_vfio_pci_unmap_bar(QEMUVFIOState *s, int > index, void *bar, > } > > /** > - * Initialize device IRQ with @irq_type and register an event notifier. > + * Initialize device IRQ @index with @irq_type > + * and register an event notifier. > */ > int qemu_vfio_pci_init_irq(QEMUVFIOState *s, EventNotifier *e, > - int irq_type, Error **errp) > + int irq_type, unsigned index, Error **errp) > { But MSI-X will expose the VFIO_IRQ_INFO_NORESIZE flag, which means that we cannot incrementally enable additional subindexes, aka vectors, without first disabling and re-enabling the entire index/irq_type. Therefore this is exposing an API that isn't actually supported. Thanks, Alex > int r; > struct vfio_irq_set *irq_set; > @@ -193,6 +194,11 @@ int qemu_vfio_pci_init_irq(QEMUVFIOState *s, > EventNotifier *e, > return -EINVAL; > } > trace_qemu_vfio_pci_init_irq(irq_info.count); > + if (index >= irq_info.count) { > + error_setg(errp, "Device has %"PRIu32" interrupts (requested index > %u)", > + irq_info.count, index); > + return -EINVAL; > + } > > irq_set_size = sizeof(*irq_set) + sizeof(int32_t); > irq_set = g_malloc0(irq_set_size); > @@ -202,7 +208,7 @@ int qemu_vfio_pci_init_irq(QEMUVFIOState *s, > EventNotifier *e, > .argsz = irq_set_size, > .flags = VFIO_IRQ_SET_DATA_EVENTFD | VFIO_IRQ_SET_ACTION_TRIGGER, > .index = irq_info.index, > - .start = 0, > + .start = index, > .count = 1, > }; >