From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:41777) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1aivRY-0001fr-Ty for qemu-devel@nongnu.org; Wed, 23 Mar 2016 22:56:17 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1aivRV-0000wX-ML for qemu-devel@nongnu.org; Wed, 23 Mar 2016 22:56:16 -0400 From: Peter Xu Date: Thu, 24 Mar 2016 10:55:41 +0800 Message-Id: <1458788142-17509-4-git-send-email-peterx@redhat.com> In-Reply-To: <1458788142-17509-1-git-send-email-peterx@redhat.com> References: <1458788142-17509-1-git-send-email-peterx@redhat.com> Subject: [Qemu-devel] [PATCH v7 3/4] kvm: add kvm_device_supported() helper function List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Cc: wei@redhat.com, peter.maydell@linaro.org, drjones@redhat.com, mdroth@linux.vnet.ibm.com, libvir-list@redhat.com, armbru@redhat.com, peterx@redhat.com, abologna@redhat.com, qemu-arm@nongnu.org, serge.fdrv@gmail.com, christoffer.dall@linaro.org This can be used when probing whether KVM support specific device. Here, a raw vmfd is used. Signed-off-by: Peter Xu --- include/sysemu/kvm.h | 9 +++++++++ kvm-all.c | 15 +++++++++++++++ 2 files changed, 24 insertions(+) diff --git a/include/sysemu/kvm.h b/include/sysemu/kvm.h index 6695fa7..0e18f15 100644 --- a/include/sysemu/kvm.h +++ b/include/sysemu/kvm.h @@ -306,6 +306,15 @@ void kvm_device_access(int fd, int group, uint64_t attr, */ int kvm_create_device(KVMState *s, uint64_t type, bool test); +/** + * kvm_device_supported - probe whether KVM supports specific device + * + * @vmfd: The fd handler for VM + * @type: type of device + * + * @return: true if supported, otherwise false. + */ +bool kvm_device_supported(int vmfd, uint64_t type); /* Arch specific hooks */ diff --git a/kvm-all.c b/kvm-all.c index 44c0464..e7b66df 100644 --- a/kvm-all.c +++ b/kvm-all.c @@ -2339,6 +2339,21 @@ int kvm_create_device(KVMState *s, uint64_t type, bool test) return test ? 0 : create_dev.fd; } +bool kvm_device_supported(int vmfd, uint64_t type) +{ + struct kvm_create_device create_dev = { + .type = type, + .fd = -1, + .flags = KVM_CREATE_DEVICE_TEST, + }; + + if (ioctl(vmfd, KVM_CHECK_EXTENSION, KVM_CAP_DEVICE_CTRL) <= 0) { + return false; + } + + return (ioctl(vmfd, KVM_CREATE_DEVICE, &create_dev) >= 0); +} + int kvm_set_one_reg(CPUState *cs, uint64_t id, void *source) { struct kvm_one_reg reg; -- 2.4.3