Populate /sys/hypervisor with entries for Hyper-V. This patch adds /sys/hypervisor/type which contains "Hyper-V".
Signed-off-by: Nuno Das Neves <[email protected]> --- .../ABI/stable/sysfs-hypervisor-hyperv | 7 ++++ drivers/hv/Kconfig | 10 +++++ drivers/hv/Makefile | 7 ++-- drivers/hv/sys-hypervisor.c | 41 +++++++++++++++++++ 4 files changed, 62 insertions(+), 3 deletions(-) create mode 100644 Documentation/ABI/stable/sysfs-hypervisor-hyperv create mode 100644 drivers/hv/sys-hypervisor.c diff --git a/Documentation/ABI/stable/sysfs-hypervisor-hyperv b/Documentation/ABI/stable/sysfs-hypervisor-hyperv new file mode 100644 index 000000000000..58380ea81315 --- /dev/null +++ b/Documentation/ABI/stable/sysfs-hypervisor-hyperv @@ -0,0 +1,7 @@ +What: /sys/hypervisor/type +Date: July 2019 +KernelVersion: 5.2.1 +Contact: [email protected] +Description: If running under Hyper-V: + Type of hypervisor: + "Hyper-V": Hyper-V hypervisor diff --git a/drivers/hv/Kconfig b/drivers/hv/Kconfig index 1c1a2514d6f3..e693adf0b77f 100644 --- a/drivers/hv/Kconfig +++ b/drivers/hv/Kconfig @@ -25,4 +25,14 @@ config HYPERV_BALLOON help Select this option to enable Hyper-V Balloon driver. +config HYPERV_SYS_HYPERVISOR + bool "Create Hyper-V entries under /sys/hypervisor" + depends on HYPERV && SYSFS + select SYS_HYPERVISOR + default y + help + Create Hyper-V entries under /sys/hypervisor (e.g., type). When running + native or on another hypervisor, /sys/hypervisor may still be + present, but it will have no Hyper-V entries. + endmenu diff --git a/drivers/hv/Makefile b/drivers/hv/Makefile index a1eec7177c2d..87f569659555 100644 --- a/drivers/hv/Makefile +++ b/drivers/hv/Makefile @@ -1,7 +1,8 @@ # SPDX-License-Identifier: GPL-2.0 -obj-$(CONFIG_HYPERV) += hv_vmbus.o -obj-$(CONFIG_HYPERV_UTILS) += hv_utils.o -obj-$(CONFIG_HYPERV_BALLOON) += hv_balloon.o +obj-$(CONFIG_HYPERV) += hv_vmbus.o +obj-$(CONFIG_HYPERV_UTILS) += hv_utils.o +obj-$(CONFIG_HYPERV_BALLOON) += hv_balloon.o +obj-$(CONFIG_HYPERV_SYS_HYPERVISOR) += sys-hypervisor.o CFLAGS_hv_trace.o = -I$(src) CFLAGS_hv_balloon.o = -I$(src) diff --git a/drivers/hv/sys-hypervisor.c b/drivers/hv/sys-hypervisor.c new file mode 100644 index 000000000000..eb3d2a6502c4 --- /dev/null +++ b/drivers/hv/sys-hypervisor.c @@ -0,0 +1,41 @@ +// SPDX-License-Identifier: GPL-2.0 + +/* + * Copyright (C) 2019, Microsoft, Inc. + * + * Authored by: Nuno Das Neves <[email protected]> + */ + +#include <linux/kernel.h> +#include <linux/init.h> +#include <linux/kobject.h> +#include <linux/err.h> + +#include <asm/hypervisor.h> + +static ssize_t type_show(struct kobject *obj, + struct kobj_attribute *attr, + char *buf) +{ + return sprintf(buf, "Hyper-V\n"); +} + +static struct kobj_attribute type_attr = __ATTR_RO(type); + +static int __init hyperv_sysfs_type_init(void) +{ + return sysfs_create_file(hypervisor_kobj, &type_attr.attr); +} + +static int __init hyper_sysfs_init(void) +{ + int ret; + + if (!hypervisor_is_type(X86_HYPER_MS_HYPERV)) + return -ENODEV; + + ret = hyperv_sysfs_type_init(); + + return ret; +} +device_initcall(hyper_sysfs_init); -- 2.17.1
