Re: [PATCH 3/4] qemu: capabilities: Introduce QEMU_CAPS_BUS_FLOPPY

On Mon, May 26, 2025 at 15:08:09 +0200, Michal Prívozník wrote: > On 5/26/25 09:57, Peter Krempa via Devel wrote: >> From: Peter Krempa <pkrempa(a)redhat.com&gt; >> >> Introduce a common capability for support of floppy devices by qemu. >> >> Floppy support can be compiled out ('FDC', 'FDC_ISA', 'FDC_SYSBUS' qemu >> Kconfig options) and also isn't supported by all architectures. Add a >> capability that will check for 'isa-fdc' and 'sysbus-fdc' devices and >> signal that given qemu supports the floppy bus. >> >> Signed-off-by: Peter Krempa <pkrempa(a)redhat.com&gt; >> --- >> src/qemu/qemu_capabilities.c | 3 +++ >> src/qemu/qemu_capabilities.h | 1 + >> tests/qemucapabilitiesdata/caps_10.0.0_ppc64.xml | 1 + >> tests/qemucapabilitiesdata/caps_10.0.0_x86_64+amdsev.xml | 1 + >> tests/qemucapabilitiesdata/caps_10.0.0_x86_64.xml | 1 + >> tests/qemucapabilitiesdata/caps_6.2.0_ppc64.xml | 1 + >> tests/qemucapabilitiesdata/caps_6.2.0_x86_64.xml | 1 + >> tests/qemucapabilitiesdata/caps_7.0.0_ppc64.xml | 1 + >> tests/qemucapabilitiesdata/caps_7.0.0_x86_64.xml | 1 + >> tests/qemucapabilitiesdata/caps_7.1.0_ppc64.xml | 1 + >> tests/qemucapabilitiesdata/caps_7.1.0_x86_64.xml | 1 + >> tests/qemucapabilitiesdata/caps_7.2.0_ppc.xml | 1 + >> tests/qemucapabilitiesdata/caps_7.2.0_x86_64+hvf.xml | 1 + >> tests/qemucapabilitiesdata/caps_7.2.0_x86_64.xml | 1 + >> tests/qemucapabilitiesdata/caps_8.0.0_x86_64.xml | 1 + >> tests/qemucapabilitiesdata/caps_8.1.0_x86_64.xml | 1 + >> tests/qemucapabilitiesdata/caps_8.2.0_x86_64.xml | 1 + >> tests/qemucapabilitiesdata/caps_9.0.0_sparc.xml | 1 + >> tests/qemucapabilitiesdata/caps_9.0.0_x86_64.xml | 1 + >> tests/qemucapabilitiesdata/caps_9.1.0_x86_64.xml | 1 + >> tests/qemucapabilitiesdata/caps_9.2.0_x86_64+amdsev.xml | 1 + >> tests/qemucapabilitiesdata/caps_9.2.0_x86_64.xml | 1 + >> 22 files changed, 24 insertions(+) >> >> diff --git a/src/qemu/qemu_capabilities.c b/src/qemu/qemu_capabilities.c >> index 19716497d8..39cf23ebe7 100644 >> --- a/src/qemu/qemu_capabilities.c >> +++ b/src/qemu/qemu_capabilities.c >> @@ -733,6 +733,7 @@ VIR_ENUM_IMPL(virQEMUCaps, >> /* 475 */ >> "virtio-scsi.iothread-mapping", /* QEMU_CAPS_VIRTIO_SCSI_IOTHREAD_MAPPING */ >> "machine.virt.highmem-mmio-size", /* QEMU_CAPS_MACHINE_VIRT_HIGHMEM_MMIO_SIZE */ >> + "bus-floppy", /* QEMU_CAPS_BUS_FLOPPY */ >> ); >> >> >> @@ -1386,6 +1387,8 @@ struct virQEMUCapsStringFlags virQEMUCapsObjectTypes[] = { >> { "pvscsi", QEMU_CAPS_SCSI_PVSCSI }, >> { "spapr-tpm-proxy", QEMU_CAPS_DEVICE_SPAPR_TPM_PROXY }, >> { "vmport", QEMU_CAPS_MACHINE_VMPORT_OPT }, >> + { "isa-fdc", QEMU_CAPS_BUS_FLOPPY }, >> + { "sysbus-fdc", QEMU_CAPS_BUS_FLOPPY }, >> /* >> * We don't probe 'esp' directly, because it is often reported >> * as present for all QEMU binaries, due to it being enabled >> diff --git a/src/qemu/qemu_capabilities.h b/src/qemu/qemu_capabilities.h >> index df33212a34..814ad222ae 100644 >> --- a/src/qemu/qemu_capabilities.h >> +++ b/src/qemu/qemu_capabilities.h >> @@ -714,6 +714,7 @@ typedef enum { /* virQEMUCapsFlags grouping marker for syntax-check */ >> /* 475 */ >> QEMU_CAPS_VIRTIO_SCSI_IOTHREAD_MAPPING, /* virtio-scsi supports per-virtqueue iothread mapping */ >> QEMU_CAPS_MACHINE_VIRT_HIGHMEM_MMIO_SIZE, /* -machine virt,highmem-mmio-size=<size> */ >> + QEMU_CAPS_BUS_FLOPPY, /* floppy bus supported (isa-fdc/sysbus-fdc) */ >> >> QEMU_CAPS_LAST /* this must always be the last item */ >> } virQEMUCapsFlags; >> diff --git a/tests/qemucapabilitiesdata/caps_10.0.0_ppc64.xml b/tests/qemucapabilitiesdata/caps_10.0.0_ppc64.xml >> index 1afe4ff7f3..967b5e0cbc 100644 >> --- a/tests/qemucapabilitiesdata/caps_10.0.0_ppc64.xml >> +++ b/tests/qemucapabilitiesdata/caps_10.0.0_ppc64.xml >> @@ -168,6 +168,7 @@ >> <flag name='blockdev-set-active'/> >> <flag name='shim'/> >> <flag name='virtio-scsi.iothread-mapping'/> >> + <flag name='bus-floppy'/> > > Does this mean qemu-system-ppc64 does support floppy? Or is the support > specific to pseries-* machine types? IIUC non-pseries machines do support floppy. > Or this is case of our handcrafted caps file again? This is actually real caps. E.g. on fedora I get: $ qemu-system-ppc64 -device ? | grep fdc name "isa-fdc", bus ISA, desc "virtual floppy controller" (I do agree that having a *ISA* fdc on a ppc64 machine is questionable but it is what qemu actually reports.)