[libvirt] [RFC PATCH 6/6] qemu: Format pseries.cap-hpt-mps on the command line

This makes the feature fully functional. Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1571078 Signed-off-by: Andrea Bolognani <abologna(a)redhat.com&gt; --- src/qemu/qemu_command.c | 26 ++++++++++++++++++++ tests/qemuxml2argvdata/pseries-features.args | 3 ++- 2 files changed, 28 insertions(+), 1 deletion(-) diff --git a/src/qemu/qemu_command.c b/src/qemu/qemu_command.c index b446a08613..983839e81c 100644 --- a/src/qemu/qemu_command.c +++ b/src/qemu/qemu_command.c @@ -7193,6 +7193,32 @@ qemuBuildMachineCommandLine(virCommandPtr cmd, virBufferAsprintf(&buf, ",resize-hpt=%s", str); } + + if (def->hpt_maxpagesize > 0) { + unsigned long long tmp = def->hpt_maxpagesize; + unsigned int shifts = 0; + + if (!virQEMUCapsGet(qemuCaps, QEMU_CAPS_MACHINE_PSERIES_CAP_HPT_MPS)) { + virReportError(VIR_ERR_CONFIG_UNSUPPORTED, "%s", + _("Limiting the page size for HPT guest is " + "not supported by this QEMU binary")); + goto cleanup; + } + + /* QEMU expects the argument to be a number of left shifts: + * for example, if you wanted to limit the guest to 4 KiB pages, + * since 4096 == 1 << 12, you would need to add cap-hpt-mps=12 + * to the command line. + * + * Convert from our internal representation, which is bytes, + * to the one QEMU expects */ + while (tmp > 1) { + tmp = tmp >> 1; + shifts++; + } + + virBufferAsprintf(&buf, ",cap-hpt-mps=%u", shifts); + } } if (cpu && cpu->model && diff --git a/tests/qemuxml2argvdata/pseries-features.args b/tests/qemuxml2argvdata/pseries-features.args index f5c1959cca..4e581a69a1 100644 --- a/tests/qemuxml2argvdata/pseries-features.args +++ b/tests/qemuxml2argvdata/pseries-features.args @@ -7,7 +7,8 @@ QEMU_AUDIO_DRV=none \ /usr/bin/qemu-system-ppc64 \ -name guest \ -S \ --machine pseries,accel=tcg,usb=off,dump-guest-core=off,resize-hpt=required \ +-machine pseries,accel=tcg,usb=off,dump-guest-core=off,resize-hpt=required,\ +cap-hpt-mps=30 \ -m 512 \ -smp 1,sockets=1,cores=1,threads=1 \ -uuid 1ccfd97d-5eb4-478a-bbe6-88d254c16db7 \ -- 2.17.0