sys-hypervisor.c

Go to the documentation of this file.

/*
 *  copyright (c) 2006 IBM Corporation
 *  Authored by: Mike D. Day <[email protected]>
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License version 2 as
 *  published by the Free Software Foundation.
 */

#include <linux/slab.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/kobject.h>
#include <linux/err.h>

#include <asm/xen/hypervisor.h>
#include <asm/xen/hypercall.h>

#include <xen/xen.h>
#include <xen/xenbus.h>
#include <xen/interface/xen.h>
#include <xen/interface/version.h>

#define HYPERVISOR_ATTR_RO(_name) \
static struct hyp_sysfs_attr  _name##_attr = __ATTR_RO(_name)

#define HYPERVISOR_ATTR_RW(_name) \
static struct hyp_sysfs_attr _name##_attr = \
    __ATTR(_name, 0644, _name##_show, _name##_store)

struct hyp_sysfs_attr {
    struct attribute attr;
    ssize_t (*show)(struct hyp_sysfs_attr *, char *);
    ssize_t (*store)(struct hyp_sysfs_attr *, const char *, size_t);
    void *hyp_attr_data;
};

static ssize_t type_show(struct hyp_sysfs_attr *attr, char *buffer)
{
    return sprintf(buffer, "xen\n");
}

HYPERVISOR_ATTR_RO(type);

static int __init xen_sysfs_type_init(void)
{
    return sysfs_create_file(hypervisor_kobj, &type_attr.attr);
}

static void xen_sysfs_type_destroy(void)
{
    sysfs_remove_file(hypervisor_kobj, &type_attr.attr);
}

/* xen version attributes */
static ssize_t major_show(struct hyp_sysfs_attr *attr, char *buffer)
{
    int version = HYPERVISOR_xen_version(XENVER_version, NULL);
    if (version)
        return sprintf(buffer, "%d\n", version >> 16);
    return -ENODEV;
}

HYPERVISOR_ATTR_RO(major);

static ssize_t minor_show(struct hyp_sysfs_attr *attr, char *buffer)
{
    int version = HYPERVISOR_xen_version(XENVER_version, NULL);
    if (version)
        return sprintf(buffer, "%d\n", version & 0xff);
    return -ENODEV;
}

HYPERVISOR_ATTR_RO(minor);

static ssize_t extra_show(struct hyp_sysfs_attr *attr, char *buffer)
{
    int ret = -ENOMEM;
    char *extra;

    extra = kmalloc(XEN_EXTRAVERSION_LEN, GFP_KERNEL);
    if (extra) {
        ret = HYPERVISOR_xen_version(XENVER_extraversion, extra);
        if (!ret)
            ret = sprintf(buffer, "%s\n", extra);
        kfree(extra);
    }

    return ret;
}

HYPERVISOR_ATTR_RO(extra);

static struct attribute *version_attrs[] = {
    &major_attr.attr,
    &minor_attr.attr,
    &extra_attr.attr,
    NULL
};

static const struct attribute_group version_group = {
    .name = "version",
    .attrs = version_attrs,
};

static int __init xen_sysfs_version_init(void)
{
    return sysfs_create_group(hypervisor_kobj, &version_group);
}

static void xen_sysfs_version_destroy(void)
{
    sysfs_remove_group(hypervisor_kobj, &version_group);
}

/* UUID */

static ssize_t uuid_show_fallback(struct hyp_sysfs_attr *attr, char *buffer)
{
    char *vm, *val;
    int ret;
    extern int xenstored_ready;

    if (!xenstored_ready)
        return -EBUSY;

    vm = xenbus_read(XBT_NIL, "vm", "", NULL);
    if (IS_ERR(vm))
        return PTR_ERR(vm);
    val = xenbus_read(XBT_NIL, vm, "uuid", NULL);
    kfree(vm);
    if (IS_ERR(val))
        return PTR_ERR(val);
    ret = sprintf(buffer, "%s\n", val);
    kfree(val);
    return ret;
}

static ssize_t uuid_show(struct hyp_sysfs_attr *attr, char *buffer)
{
    xen_domain_handle_t uuid;
    int ret;
    ret = HYPERVISOR_xen_version(XENVER_guest_handle, uuid);
    if (ret)
        return uuid_show_fallback(attr, buffer);
    ret = sprintf(buffer, "%pU\n", uuid);
    return ret;
}

HYPERVISOR_ATTR_RO(uuid);

static int __init xen_sysfs_uuid_init(void)
{
    return sysfs_create_file(hypervisor_kobj, &uuid_attr.attr);
}

static void xen_sysfs_uuid_destroy(void)
{
    sysfs_remove_file(hypervisor_kobj, &uuid_attr.attr);
}

/* xen compilation attributes */

static ssize_t compiler_show(struct hyp_sysfs_attr *attr, char *buffer)
{
    int ret = -ENOMEM;
    struct xen_compile_info *info;

    info = kmalloc(sizeof(struct xen_compile_info), GFP_KERNEL);
    if (info) {
        ret = HYPERVISOR_xen_version(XENVER_compile_info, info);
        if (!ret)
            ret = sprintf(buffer, "%s\n", info->compiler);
        kfree(info);
    }

    return ret;
}

HYPERVISOR_ATTR_RO(compiler);

static ssize_t compiled_by_show(struct hyp_sysfs_attr *attr, char *buffer)
{
    int ret = -ENOMEM;
    struct xen_compile_info *info;

    info = kmalloc(sizeof(struct xen_compile_info), GFP_KERNEL);
    if (info) {
        ret = HYPERVISOR_xen_version(XENVER_compile_info, info);
        if (!ret)
            ret = sprintf(buffer, "%s\n", info->compile_by);
        kfree(info);
    }

    return ret;
}

HYPERVISOR_ATTR_RO(compiled_by);

static ssize_t compile_date_show(struct hyp_sysfs_attr *attr, char *buffer)
{
    int ret = -ENOMEM;
    struct xen_compile_info *info;

    info = kmalloc(sizeof(struct xen_compile_info), GFP_KERNEL);
    if (info) {
        ret = HYPERVISOR_xen_version(XENVER_compile_info, info);
        if (!ret)
            ret = sprintf(buffer, "%s\n", info->compile_date);
        kfree(info);
    }

    return ret;
}

HYPERVISOR_ATTR_RO(compile_date);

static struct attribute *xen_compile_attrs[] = {
    &compiler_attr.attr,
    &compiled_by_attr.attr,
    &compile_date_attr.attr,
    NULL
};

static const struct attribute_group xen_compilation_group = {
    .name = "compilation",
    .attrs = xen_compile_attrs,
};

static int __init xen_compilation_init(void)
{
    return sysfs_create_group(hypervisor_kobj, &xen_compilation_group);
}

static void xen_compilation_destroy(void)
{
    sysfs_remove_group(hypervisor_kobj, &xen_compilation_group);
}

/* xen properties info */

static ssize_t capabilities_show(struct hyp_sysfs_attr *attr, char *buffer)
{
    int ret = -ENOMEM;
    char *caps;

    caps = kmalloc(XEN_CAPABILITIES_INFO_LEN, GFP_KERNEL);
    if (caps) {
        ret = HYPERVISOR_xen_version(XENVER_capabilities, caps);
        if (!ret)
            ret = sprintf(buffer, "%s\n", caps);
        kfree(caps);
    }

    return ret;
}

HYPERVISOR_ATTR_RO(capabilities);

static ssize_t changeset_show(struct hyp_sysfs_attr *attr, char *buffer)
{
    int ret = -ENOMEM;
    char *cset;

    cset = kmalloc(XEN_CHANGESET_INFO_LEN, GFP_KERNEL);
    if (cset) {
        ret = HYPERVISOR_xen_version(XENVER_changeset, cset);
        if (!ret)
            ret = sprintf(buffer, "%s\n", cset);
        kfree(cset);
    }

    return ret;
}

HYPERVISOR_ATTR_RO(changeset);

static ssize_t virtual_start_show(struct hyp_sysfs_attr *attr, char *buffer)
{
    int ret = -ENOMEM;
    struct xen_platform_parameters *parms;

    parms = kmalloc(sizeof(struct xen_platform_parameters), GFP_KERNEL);
    if (parms) {
        ret = HYPERVISOR_xen_version(XENVER_platform_parameters,
                         parms);
        if (!ret)
            ret = sprintf(buffer, "%"PRI_xen_ulong"\n",
                      parms->virt_start);
        kfree(parms);
    }

    return ret;
}

HYPERVISOR_ATTR_RO(virtual_start);

static ssize_t pagesize_show(struct hyp_sysfs_attr *attr, char *buffer)
{
    int ret;

    ret = HYPERVISOR_xen_version(XENVER_pagesize, NULL);
    if (ret > 0)
        ret = sprintf(buffer, "%x\n", ret);

    return ret;
}

HYPERVISOR_ATTR_RO(pagesize);

static ssize_t xen_feature_show(int index, char *buffer)
{
    ssize_t ret;
    struct xen_feature_info info;

    info.submap_idx = index;
    ret = HYPERVISOR_xen_version(XENVER_get_features, &info);
    if (!ret)
        ret = sprintf(buffer, "%08x", info.submap);

    return ret;
}

static ssize_t features_show(struct hyp_sysfs_attr *attr, char *buffer)
{
    ssize_t len;
    int i;

    len = 0;
    for (i = XENFEAT_NR_SUBMAPS-1; i >= 0; i--) {
        int ret = xen_feature_show(i, buffer + len);
        if (ret < 0) {
            if (len == 0)
                len = ret;
            break;
        }
        len += ret;
    }
    if (len > 0)
        buffer[len++] = '\n';

    return len;
}

HYPERVISOR_ATTR_RO(features);

static struct attribute *xen_properties_attrs[] = {
    &capabilities_attr.attr,
    &changeset_attr.attr,
    &virtual_start_attr.attr,
    &pagesize_attr.attr,
    &features_attr.attr,
    NULL
};

static const struct attribute_group xen_properties_group = {
    .name = "properties",
    .attrs = xen_properties_attrs,
};

static int __init xen_properties_init(void)
{
    return sysfs_create_group(hypervisor_kobj, &xen_properties_group);
}

static void xen_properties_destroy(void)
{
    sysfs_remove_group(hypervisor_kobj, &xen_properties_group);
}

static int __init hyper_sysfs_init(void)
{
    int ret;

    if (!xen_domain())
        return -ENODEV;

    ret = xen_sysfs_type_init();
    if (ret)
        goto out;
    ret = xen_sysfs_version_init();
    if (ret)
        goto version_out;
    ret = xen_compilation_init();
    if (ret)
        goto comp_out;
    ret = xen_sysfs_uuid_init();
    if (ret)
        goto uuid_out;
    ret = xen_properties_init();
    if (ret)
        goto prop_out;

    goto out;

prop_out:
    xen_sysfs_uuid_destroy();
uuid_out:
    xen_compilation_destroy();
comp_out:
    xen_sysfs_version_destroy();
version_out:
    xen_sysfs_type_destroy();
out:
    return ret;
}

static void __exit hyper_sysfs_exit(void)
{
    xen_properties_destroy();
    xen_compilation_destroy();
    xen_sysfs_uuid_destroy();
    xen_sysfs_version_destroy();
    xen_sysfs_type_destroy();

}
module_init(hyper_sysfs_init);
module_exit(hyper_sysfs_exit);

static ssize_t hyp_sysfs_show(struct kobject *kobj,
                  struct attribute *attr,
                  char *buffer)
{
    struct hyp_sysfs_attr *hyp_attr;
    hyp_attr = container_of(attr, struct hyp_sysfs_attr, attr);
    if (hyp_attr->show)
        return hyp_attr->show(hyp_attr, buffer);
    return 0;
}

static ssize_t hyp_sysfs_store(struct kobject *kobj,
                   struct attribute *attr,
                   const char *buffer,
                   size_t len)
{
    struct hyp_sysfs_attr *hyp_attr;
    hyp_attr = container_of(attr, struct hyp_sysfs_attr, attr);
    if (hyp_attr->store)
        return hyp_attr->store(hyp_attr, buffer, len);
    return 0;
}

static const struct sysfs_ops hyp_sysfs_ops = {
    .show = hyp_sysfs_show,
    .store = hyp_sysfs_store,
};

static struct kobj_type hyp_sysfs_kobj_type = {
    .sysfs_ops = &hyp_sysfs_ops,
};

static int __init hypervisor_subsys_init(void)
{
    if (!xen_domain())
        return -ENODEV;

    hypervisor_kobj->ktype = &hyp_sysfs_kobj_type;
    return 0;
}
device_initcall(hypervisor_subsys_init);