swh:1:snp:173f8deb0c56c557784b4fd217e7608ac6197844
Tip revision: 39a8804455fb23f09157341d3ba7db6d7ae6ee76 authored by Linus Torvalds on 12 April 2015, 22:12:50 UTC
Linux 4.0
Linux 4.0
Tip revision: 39a8804
vmbus_drv.c
/*
* Copyright (c) 2009, Microsoft Corporation.
*
* This program is free software; you can redistribute it and/or modify it
* under the terms and conditions of the GNU General Public License,
* version 2, as published by the Free Software Foundation.
*
* This program is distributed in the hope it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
* more details.
*
* You should have received a copy of the GNU General Public License along with
* this program; if not, write to the Free Software Foundation, Inc., 59 Temple
* Place - Suite 330, Boston, MA 02111-1307 USA.
*
* Authors:
* Haiyang Zhang <haiyangz@microsoft.com>
* Hank Janssen <hjanssen@microsoft.com>
* K. Y. Srinivasan <kys@microsoft.com>
*
*/
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <linux/init.h>
#include <linux/module.h>
#include <linux/device.h>
#include <linux/interrupt.h>
#include <linux/sysctl.h>
#include <linux/slab.h>
#include <linux/acpi.h>
#include <linux/completion.h>
#include <linux/hyperv.h>
#include <linux/kernel_stat.h>
#include <linux/clockchips.h>
#include <asm/hyperv.h>
#include <asm/hypervisor.h>
#include <asm/mshyperv.h>
#include "hyperv_vmbus.h"
static struct acpi_device *hv_acpi_dev;
static struct tasklet_struct msg_dpc;
static struct completion probe_event;
static int irq;
struct resource hyperv_mmio = {
.name = "hyperv mmio",
.flags = IORESOURCE_MEM,
};
EXPORT_SYMBOL_GPL(hyperv_mmio);
static int vmbus_exists(void)
{
if (hv_acpi_dev == NULL)
return -ENODEV;
return 0;
}
#define VMBUS_ALIAS_LEN ((sizeof((struct hv_vmbus_device_id *)0)->guid) * 2)
static void print_alias_name(struct hv_device *hv_dev, char *alias_name)
{
int i;
for (i = 0; i < VMBUS_ALIAS_LEN; i += 2)
sprintf(&alias_name[i], "%02x", hv_dev->dev_type.b[i/2]);
}
static u8 channel_monitor_group(struct vmbus_channel *channel)
{
return (u8)channel->offermsg.monitorid / 32;
}
static u8 channel_monitor_offset(struct vmbus_channel *channel)
{
return (u8)channel->offermsg.monitorid % 32;
}
static u32 channel_pending(struct vmbus_channel *channel,
struct hv_monitor_page *monitor_page)
{
u8 monitor_group = channel_monitor_group(channel);
return monitor_page->trigger_group[monitor_group].pending;
}
static u32 channel_latency(struct vmbus_channel *channel,
struct hv_monitor_page *monitor_page)
{
u8 monitor_group = channel_monitor_group(channel);
u8 monitor_offset = channel_monitor_offset(channel);
return monitor_page->latency[monitor_group][monitor_offset];
}
static u32 channel_conn_id(struct vmbus_channel *channel,
struct hv_monitor_page *monitor_page)
{
u8 monitor_group = channel_monitor_group(channel);
u8 monitor_offset = channel_monitor_offset(channel);
return monitor_page->parameter[monitor_group][monitor_offset].connectionid.u.id;
}
static ssize_t id_show(struct device *dev, struct device_attribute *dev_attr,
char *buf)
{
struct hv_device *hv_dev = device_to_hv_device(dev);
if (!hv_dev->channel)
return -ENODEV;
return sprintf(buf, "%d\n", hv_dev->channel->offermsg.child_relid);
}
static DEVICE_ATTR_RO(id);
static ssize_t state_show(struct device *dev, struct device_attribute *dev_attr,
char *buf)
{
struct hv_device *hv_dev = device_to_hv_device(dev);
if (!hv_dev->channel)
return -ENODEV;
return sprintf(buf, "%d\n", hv_dev->channel->state);
}
static DEVICE_ATTR_RO(state);
static ssize_t monitor_id_show(struct device *dev,
struct device_attribute *dev_attr, char *buf)
{
struct hv_device *hv_dev = device_to_hv_device(dev);
if (!hv_dev->channel)
return -ENODEV;
return sprintf(buf, "%d\n", hv_dev->channel->offermsg.monitorid);
}
static DEVICE_ATTR_RO(monitor_id);
static ssize_t class_id_show(struct device *dev,
struct device_attribute *dev_attr, char *buf)
{
struct hv_device *hv_dev = device_to_hv_device(dev);
if (!hv_dev->channel)
return -ENODEV;
return sprintf(buf, "{%pUl}\n",
hv_dev->channel->offermsg.offer.if_type.b);
}
static DEVICE_ATTR_RO(class_id);
static ssize_t device_id_show(struct device *dev,
struct device_attribute *dev_attr, char *buf)
{
struct hv_device *hv_dev = device_to_hv_device(dev);
if (!hv_dev->channel)
return -ENODEV;
return sprintf(buf, "{%pUl}\n",
hv_dev->channel->offermsg.offer.if_instance.b);
}
static DEVICE_ATTR_RO(device_id);
static ssize_t modalias_show(struct device *dev,
struct device_attribute *dev_attr, char *buf)
{
struct hv_device *hv_dev = device_to_hv_device(dev);
char alias_name[VMBUS_ALIAS_LEN + 1];
print_alias_name(hv_dev, alias_name);
return sprintf(buf, "vmbus:%s\n", alias_name);
}
static DEVICE_ATTR_RO(modalias);
static ssize_t server_monitor_pending_show(struct device *dev,
struct device_attribute *dev_attr,
char *buf)
{
struct hv_device *hv_dev = device_to_hv_device(dev);
if (!hv_dev->channel)
return -ENODEV;
return sprintf(buf, "%d\n",
channel_pending(hv_dev->channel,
vmbus_connection.monitor_pages[1]));
}
static DEVICE_ATTR_RO(server_monitor_pending);
static ssize_t client_monitor_pending_show(struct device *dev,
struct device_attribute *dev_attr,
char *buf)
{
struct hv_device *hv_dev = device_to_hv_device(dev);
if (!hv_dev->channel)
return -ENODEV;
return sprintf(buf, "%d\n",
channel_pending(hv_dev->channel,
vmbus_connection.monitor_pages[1]));
}
static DEVICE_ATTR_RO(client_monitor_pending);
static ssize_t server_monitor_latency_show(struct device *dev,
struct device_attribute *dev_attr,
char *buf)
{
struct hv_device *hv_dev = device_to_hv_device(dev);
if (!hv_dev->channel)
return -ENODEV;
return sprintf(buf, "%d\n",
channel_latency(hv_dev->channel,
vmbus_connection.monitor_pages[0]));
}
static DEVICE_ATTR_RO(server_monitor_latency);
static ssize_t client_monitor_latency_show(struct device *dev,
struct device_attribute *dev_attr,
char *buf)
{
struct hv_device *hv_dev = device_to_hv_device(dev);
if (!hv_dev->channel)
return -ENODEV;
return sprintf(buf, "%d\n",
channel_latency(hv_dev->channel,
vmbus_connection.monitor_pages[1]));
}
static DEVICE_ATTR_RO(client_monitor_latency);
static ssize_t server_monitor_conn_id_show(struct device *dev,
struct device_attribute *dev_attr,
char *buf)
{
struct hv_device *hv_dev = device_to_hv_device(dev);
if (!hv_dev->channel)
return -ENODEV;
return sprintf(buf, "%d\n",
channel_conn_id(hv_dev->channel,
vmbus_connection.monitor_pages[0]));
}
static DEVICE_ATTR_RO(server_monitor_conn_id);
static ssize_t client_monitor_conn_id_show(struct device *dev,
struct device_attribute *dev_attr,
char *buf)
{
struct hv_device *hv_dev = device_to_hv_device(dev);
if (!hv_dev->channel)
return -ENODEV;
return sprintf(buf, "%d\n",
channel_conn_id(hv_dev->channel,
vmbus_connection.monitor_pages[1]));
}
static DEVICE_ATTR_RO(client_monitor_conn_id);
static ssize_t out_intr_mask_show(struct device *dev,
struct device_attribute *dev_attr, char *buf)
{
struct hv_device *hv_dev = device_to_hv_device(dev);
struct hv_ring_buffer_debug_info outbound;
if (!hv_dev->channel)
return -ENODEV;
hv_ringbuffer_get_debuginfo(&hv_dev->channel->outbound, &outbound);
return sprintf(buf, "%d\n", outbound.current_interrupt_mask);
}
static DEVICE_ATTR_RO(out_intr_mask);
static ssize_t out_read_index_show(struct device *dev,
struct device_attribute *dev_attr, char *buf)
{
struct hv_device *hv_dev = device_to_hv_device(dev);
struct hv_ring_buffer_debug_info outbound;
if (!hv_dev->channel)
return -ENODEV;
hv_ringbuffer_get_debuginfo(&hv_dev->channel->outbound, &outbound);
return sprintf(buf, "%d\n", outbound.current_read_index);
}
static DEVICE_ATTR_RO(out_read_index);
static ssize_t out_write_index_show(struct device *dev,
struct device_attribute *dev_attr,
char *buf)
{
struct hv_device *hv_dev = device_to_hv_device(dev);
struct hv_ring_buffer_debug_info outbound;
if (!hv_dev->channel)
return -ENODEV;
hv_ringbuffer_get_debuginfo(&hv_dev->channel->outbound, &outbound);
return sprintf(buf, "%d\n", outbound.current_write_index);
}
static DEVICE_ATTR_RO(out_write_index);
static ssize_t out_read_bytes_avail_show(struct device *dev,
struct device_attribute *dev_attr,
char *buf)
{
struct hv_device *hv_dev = device_to_hv_device(dev);
struct hv_ring_buffer_debug_info outbound;
if (!hv_dev->channel)
return -ENODEV;
hv_ringbuffer_get_debuginfo(&hv_dev->channel->outbound, &outbound);
return sprintf(buf, "%d\n", outbound.bytes_avail_toread);
}
static DEVICE_ATTR_RO(out_read_bytes_avail);
static ssize_t out_write_bytes_avail_show(struct device *dev,
struct device_attribute *dev_attr,
char *buf)
{
struct hv_device *hv_dev = device_to_hv_device(dev);
struct hv_ring_buffer_debug_info outbound;
if (!hv_dev->channel)
return -ENODEV;
hv_ringbuffer_get_debuginfo(&hv_dev->channel->outbound, &outbound);
return sprintf(buf, "%d\n", outbound.bytes_avail_towrite);
}
static DEVICE_ATTR_RO(out_write_bytes_avail);
static ssize_t in_intr_mask_show(struct device *dev,
struct device_attribute *dev_attr, char *buf)
{
struct hv_device *hv_dev = device_to_hv_device(dev);
struct hv_ring_buffer_debug_info inbound;
if (!hv_dev->channel)
return -ENODEV;
hv_ringbuffer_get_debuginfo(&hv_dev->channel->inbound, &inbound);
return sprintf(buf, "%d\n", inbound.current_interrupt_mask);
}
static DEVICE_ATTR_RO(in_intr_mask);
static ssize_t in_read_index_show(struct device *dev,
struct device_attribute *dev_attr, char *buf)
{
struct hv_device *hv_dev = device_to_hv_device(dev);
struct hv_ring_buffer_debug_info inbound;
if (!hv_dev->channel)
return -ENODEV;
hv_ringbuffer_get_debuginfo(&hv_dev->channel->inbound, &inbound);
return sprintf(buf, "%d\n", inbound.current_read_index);
}
static DEVICE_ATTR_RO(in_read_index);
static ssize_t in_write_index_show(struct device *dev,
struct device_attribute *dev_attr, char *buf)
{
struct hv_device *hv_dev = device_to_hv_device(dev);
struct hv_ring_buffer_debug_info inbound;
if (!hv_dev->channel)
return -ENODEV;
hv_ringbuffer_get_debuginfo(&hv_dev->channel->inbound, &inbound);
return sprintf(buf, "%d\n", inbound.current_write_index);
}
static DEVICE_ATTR_RO(in_write_index);
static ssize_t in_read_bytes_avail_show(struct device *dev,
struct device_attribute *dev_attr,
char *buf)
{
struct hv_device *hv_dev = device_to_hv_device(dev);
struct hv_ring_buffer_debug_info inbound;
if (!hv_dev->channel)
return -ENODEV;
hv_ringbuffer_get_debuginfo(&hv_dev->channel->inbound, &inbound);
return sprintf(buf, "%d\n", inbound.bytes_avail_toread);
}
static DEVICE_ATTR_RO(in_read_bytes_avail);
static ssize_t in_write_bytes_avail_show(struct device *dev,
struct device_attribute *dev_attr,
char *buf)
{
struct hv_device *hv_dev = device_to_hv_device(dev);
struct hv_ring_buffer_debug_info inbound;
if (!hv_dev->channel)
return -ENODEV;
hv_ringbuffer_get_debuginfo(&hv_dev->channel->inbound, &inbound);
return sprintf(buf, "%d\n", inbound.bytes_avail_towrite);
}
static DEVICE_ATTR_RO(in_write_bytes_avail);
/* Set up per device attributes in /sys/bus/vmbus/devices/<bus device> */
static struct attribute *vmbus_attrs[] = {
&dev_attr_id.attr,
&dev_attr_state.attr,
&dev_attr_monitor_id.attr,
&dev_attr_class_id.attr,
&dev_attr_device_id.attr,
&dev_attr_modalias.attr,
&dev_attr_server_monitor_pending.attr,
&dev_attr_client_monitor_pending.attr,
&dev_attr_server_monitor_latency.attr,
&dev_attr_client_monitor_latency.attr,
&dev_attr_server_monitor_conn_id.attr,
&dev_attr_client_monitor_conn_id.attr,
&dev_attr_out_intr_mask.attr,
&dev_attr_out_read_index.attr,
&dev_attr_out_write_index.attr,
&dev_attr_out_read_bytes_avail.attr,
&dev_attr_out_write_bytes_avail.attr,
&dev_attr_in_intr_mask.attr,
&dev_attr_in_read_index.attr,
&dev_attr_in_write_index.attr,
&dev_attr_in_read_bytes_avail.attr,
&dev_attr_in_write_bytes_avail.attr,
NULL,
};
ATTRIBUTE_GROUPS(vmbus);
/*
* vmbus_uevent - add uevent for our device
*
* This routine is invoked when a device is added or removed on the vmbus to
* generate a uevent to udev in the userspace. The udev will then look at its
* rule and the uevent generated here to load the appropriate driver
*
* The alias string will be of the form vmbus:guid where guid is the string
* representation of the device guid (each byte of the guid will be
* represented with two hex characters.
*/
static int vmbus_uevent(struct device *device, struct kobj_uevent_env *env)
{
struct hv_device *dev = device_to_hv_device(device);
int ret;
char alias_name[VMBUS_ALIAS_LEN + 1];
print_alias_name(dev, alias_name);
ret = add_uevent_var(env, "MODALIAS=vmbus:%s", alias_name);
return ret;
}
static const uuid_le null_guid;
static inline bool is_null_guid(const __u8 *guid)
{
if (memcmp(guid, &null_guid, sizeof(uuid_le)))
return false;
return true;
}
/*
* Return a matching hv_vmbus_device_id pointer.
* If there is no match, return NULL.
*/
static const struct hv_vmbus_device_id *hv_vmbus_get_id(
const struct hv_vmbus_device_id *id,
const __u8 *guid)
{
for (; !is_null_guid(id->guid); id++)
if (!memcmp(&id->guid, guid, sizeof(uuid_le)))
return id;
return NULL;
}
/*
* vmbus_match - Attempt to match the specified device to the specified driver
*/
static int vmbus_match(struct device *device, struct device_driver *driver)
{
struct hv_driver *drv = drv_to_hv_drv(driver);
struct hv_device *hv_dev = device_to_hv_device(device);
if (hv_vmbus_get_id(drv->id_table, hv_dev->dev_type.b))
return 1;
return 0;
}
/*
* vmbus_probe - Add the new vmbus's child device
*/
static int vmbus_probe(struct device *child_device)
{
int ret = 0;
struct hv_driver *drv =
drv_to_hv_drv(child_device->driver);
struct hv_device *dev = device_to_hv_device(child_device);
const struct hv_vmbus_device_id *dev_id;
dev_id = hv_vmbus_get_id(drv->id_table, dev->dev_type.b);
if (drv->probe) {
ret = drv->probe(dev, dev_id);
if (ret != 0)
pr_err("probe failed for device %s (%d)\n",
dev_name(child_device), ret);
} else {
pr_err("probe not set for driver %s\n",
dev_name(child_device));
ret = -ENODEV;
}
return ret;
}
/*
* vmbus_remove - Remove a vmbus device
*/
static int vmbus_remove(struct device *child_device)
{
struct hv_driver *drv = drv_to_hv_drv(child_device->driver);
struct hv_device *dev = device_to_hv_device(child_device);
if (drv->remove)
drv->remove(dev);
else
pr_err("remove not set for driver %s\n",
dev_name(child_device));
return 0;
}
/*
* vmbus_shutdown - Shutdown a vmbus device
*/
static void vmbus_shutdown(struct device *child_device)
{
struct hv_driver *drv;
struct hv_device *dev = device_to_hv_device(child_device);
/* The device may not be attached yet */
if (!child_device->driver)
return;
drv = drv_to_hv_drv(child_device->driver);
if (drv->shutdown)
drv->shutdown(dev);
return;
}
/*
* vmbus_device_release - Final callback release of the vmbus child device
*/
static void vmbus_device_release(struct device *device)
{
struct hv_device *hv_dev = device_to_hv_device(device);
kfree(hv_dev);
}
/* The one and only one */
static struct bus_type hv_bus = {
.name = "vmbus",
.match = vmbus_match,
.shutdown = vmbus_shutdown,
.remove = vmbus_remove,
.probe = vmbus_probe,
.uevent = vmbus_uevent,
.dev_groups = vmbus_groups,
};
struct onmessage_work_context {
struct work_struct work;
struct hv_message msg;
};
static void vmbus_onmessage_work(struct work_struct *work)
{
struct onmessage_work_context *ctx;
ctx = container_of(work, struct onmessage_work_context,
work);
vmbus_onmessage(&ctx->msg);
kfree(ctx);
}
static void hv_process_timer_expiration(struct hv_message *msg, int cpu)
{
struct clock_event_device *dev = hv_context.clk_evt[cpu];
if (dev->event_handler)
dev->event_handler(dev);
msg->header.message_type = HVMSG_NONE;
/*
* Make sure the write to MessageType (ie set to
* HVMSG_NONE) happens before we read the
* MessagePending and EOMing. Otherwise, the EOMing
* will not deliver any more messages since there is
* no empty slot
*/
mb();
if (msg->header.message_flags.msg_pending) {
/*
* This will cause message queue rescan to
* possibly deliver another msg from the
* hypervisor
*/
wrmsrl(HV_X64_MSR_EOM, 0);
}
}
static void vmbus_on_msg_dpc(unsigned long data)
{
int cpu = smp_processor_id();
void *page_addr = hv_context.synic_message_page[cpu];
struct hv_message *msg = (struct hv_message *)page_addr +
VMBUS_MESSAGE_SINT;
struct onmessage_work_context *ctx;
while (1) {
if (msg->header.message_type == HVMSG_NONE) {
/* no msg */
break;
} else {
ctx = kmalloc(sizeof(*ctx), GFP_ATOMIC);
if (ctx == NULL)
continue;
INIT_WORK(&ctx->work, vmbus_onmessage_work);
memcpy(&ctx->msg, msg, sizeof(*msg));
queue_work(vmbus_connection.work_queue, &ctx->work);
}
msg->header.message_type = HVMSG_NONE;
/*
* Make sure the write to MessageType (ie set to
* HVMSG_NONE) happens before we read the
* MessagePending and EOMing. Otherwise, the EOMing
* will not deliver any more messages since there is
* no empty slot
*/
mb();
if (msg->header.message_flags.msg_pending) {
/*
* This will cause message queue rescan to
* possibly deliver another msg from the
* hypervisor
*/
wrmsrl(HV_X64_MSR_EOM, 0);
}
}
}
static void vmbus_isr(void)
{
int cpu = smp_processor_id();
void *page_addr;
struct hv_message *msg;
union hv_synic_event_flags *event;
bool handled = false;
page_addr = hv_context.synic_event_page[cpu];
if (page_addr == NULL)
return;
event = (union hv_synic_event_flags *)page_addr +
VMBUS_MESSAGE_SINT;
/*
* Check for events before checking for messages. This is the order
* in which events and messages are checked in Windows guests on
* Hyper-V, and the Windows team suggested we do the same.
*/
if ((vmbus_proto_version == VERSION_WS2008) ||
(vmbus_proto_version == VERSION_WIN7)) {
/* Since we are a child, we only need to check bit 0 */
if (sync_test_and_clear_bit(0,
(unsigned long *) &event->flags32[0])) {
handled = true;
}
} else {
/*
* Our host is win8 or above. The signaling mechanism
* has changed and we can directly look at the event page.
* If bit n is set then we have an interrup on the channel
* whose id is n.
*/
handled = true;
}
if (handled)
tasklet_schedule(hv_context.event_dpc[cpu]);
page_addr = hv_context.synic_message_page[cpu];
msg = (struct hv_message *)page_addr + VMBUS_MESSAGE_SINT;
/* Check if there are actual msgs to be processed */
if (msg->header.message_type != HVMSG_NONE) {
if (msg->header.message_type == HVMSG_TIMER_EXPIRED)
hv_process_timer_expiration(msg, cpu);
else
tasklet_schedule(&msg_dpc);
}
}
/*
* vmbus_bus_init -Main vmbus driver initialization routine.
*
* Here, we
* - initialize the vmbus driver context
* - invoke the vmbus hv main init routine
* - get the irq resource
* - retrieve the channel offers
*/
static int vmbus_bus_init(int irq)
{
int ret;
/* Hypervisor initialization...setup hypercall page..etc */
ret = hv_init();
if (ret != 0) {
pr_err("Unable to initialize the hypervisor - 0x%x\n", ret);
return ret;
}
tasklet_init(&msg_dpc, vmbus_on_msg_dpc, 0);
ret = bus_register(&hv_bus);
if (ret)
goto err_cleanup;
hv_setup_vmbus_irq(vmbus_isr);
ret = hv_synic_alloc();
if (ret)
goto err_alloc;
/*
* Initialize the per-cpu interrupt state and
* connect to the host.
*/
on_each_cpu(hv_synic_init, NULL, 1);
ret = vmbus_connect();
if (ret)
goto err_alloc;
vmbus_request_offers();
return 0;
err_alloc:
hv_synic_free();
hv_remove_vmbus_irq();
bus_unregister(&hv_bus);
err_cleanup:
hv_cleanup();
return ret;
}
/**
* __vmbus_child_driver_register - Register a vmbus's driver
* @drv: Pointer to driver structure you want to register
* @owner: owner module of the drv
* @mod_name: module name string
*
* Registers the given driver with Linux through the 'driver_register()' call
* and sets up the hyper-v vmbus handling for this driver.
* It will return the state of the 'driver_register()' call.
*
*/
int __vmbus_driver_register(struct hv_driver *hv_driver, struct module *owner, const char *mod_name)
{
int ret;
pr_info("registering driver %s\n", hv_driver->name);
ret = vmbus_exists();
if (ret < 0)
return ret;
hv_driver->driver.name = hv_driver->name;
hv_driver->driver.owner = owner;
hv_driver->driver.mod_name = mod_name;
hv_driver->driver.bus = &hv_bus;
ret = driver_register(&hv_driver->driver);
return ret;
}
EXPORT_SYMBOL_GPL(__vmbus_driver_register);
/**
* vmbus_driver_unregister() - Unregister a vmbus's driver
* @drv: Pointer to driver structure you want to un-register
*
* Un-register the given driver that was previous registered with a call to
* vmbus_driver_register()
*/
void vmbus_driver_unregister(struct hv_driver *hv_driver)
{
pr_info("unregistering driver %s\n", hv_driver->name);
if (!vmbus_exists())
driver_unregister(&hv_driver->driver);
}
EXPORT_SYMBOL_GPL(vmbus_driver_unregister);
/*
* vmbus_device_create - Creates and registers a new child device
* on the vmbus.
*/
struct hv_device *vmbus_device_create(const uuid_le *type,
const uuid_le *instance,
struct vmbus_channel *channel)
{
struct hv_device *child_device_obj;
child_device_obj = kzalloc(sizeof(struct hv_device), GFP_KERNEL);
if (!child_device_obj) {
pr_err("Unable to allocate device object for child device\n");
return NULL;
}
child_device_obj->channel = channel;
memcpy(&child_device_obj->dev_type, type, sizeof(uuid_le));
memcpy(&child_device_obj->dev_instance, instance,
sizeof(uuid_le));
return child_device_obj;
}
/*
* vmbus_device_register - Register the child device
*/
int vmbus_device_register(struct hv_device *child_device_obj)
{
int ret = 0;
static atomic_t device_num = ATOMIC_INIT(0);
dev_set_name(&child_device_obj->device, "vmbus_0_%d",
atomic_inc_return(&device_num));
child_device_obj->device.bus = &hv_bus;
child_device_obj->device.parent = &hv_acpi_dev->dev;
child_device_obj->device.release = vmbus_device_release;
/*
* Register with the LDM. This will kick off the driver/device
* binding...which will eventually call vmbus_match() and vmbus_probe()
*/
ret = device_register(&child_device_obj->device);
if (ret)
pr_err("Unable to register child device\n");
else
pr_debug("child device %s registered\n",
dev_name(&child_device_obj->device));
return ret;
}
/*
* vmbus_device_unregister - Remove the specified child device
* from the vmbus.
*/
void vmbus_device_unregister(struct hv_device *device_obj)
{
pr_debug("child device %s unregistered\n",
dev_name(&device_obj->device));
/*
* Kick off the process of unregistering the device.
* This will call vmbus_remove() and eventually vmbus_device_release()
*/
device_unregister(&device_obj->device);
}
/*
* VMBUS is an acpi enumerated device. Get the the information we
* need from DSDT.
*/
static acpi_status vmbus_walk_resources(struct acpi_resource *res, void *ctx)
{
switch (res->type) {
case ACPI_RESOURCE_TYPE_IRQ:
irq = res->data.irq.interrupts[0];
break;
case ACPI_RESOURCE_TYPE_ADDRESS64:
hyperv_mmio.start = res->data.address64.address.minimum;
hyperv_mmio.end = res->data.address64.address.maximum;
break;
}
return AE_OK;
}
static int vmbus_acpi_add(struct acpi_device *device)
{
acpi_status result;
int ret_val = -ENODEV;
hv_acpi_dev = device;
result = acpi_walk_resources(device->handle, METHOD_NAME__CRS,
vmbus_walk_resources, NULL);
if (ACPI_FAILURE(result))
goto acpi_walk_err;
/*
* The parent of the vmbus acpi device (Gen2 firmware) is the VMOD that
* has the mmio ranges. Get that.
*/
if (device->parent) {
result = acpi_walk_resources(device->parent->handle,
METHOD_NAME__CRS,
vmbus_walk_resources, NULL);
if (ACPI_FAILURE(result))
goto acpi_walk_err;
if (hyperv_mmio.start && hyperv_mmio.end)
request_resource(&iomem_resource, &hyperv_mmio);
}
ret_val = 0;
acpi_walk_err:
complete(&probe_event);
return ret_val;
}
static const struct acpi_device_id vmbus_acpi_device_ids[] = {
{"VMBUS", 0},
{"VMBus", 0},
{"", 0},
};
MODULE_DEVICE_TABLE(acpi, vmbus_acpi_device_ids);
static struct acpi_driver vmbus_acpi_driver = {
.name = "vmbus",
.ids = vmbus_acpi_device_ids,
.ops = {
.add = vmbus_acpi_add,
},
};
static int __init hv_acpi_init(void)
{
int ret, t;
if (x86_hyper != &x86_hyper_ms_hyperv)
return -ENODEV;
init_completion(&probe_event);
/*
* Get irq resources first.
*/
ret = acpi_bus_register_driver(&vmbus_acpi_driver);
if (ret)
return ret;
t = wait_for_completion_timeout(&probe_event, 5*HZ);
if (t == 0) {
ret = -ETIMEDOUT;
goto cleanup;
}
if (irq <= 0) {
ret = -ENODEV;
goto cleanup;
}
ret = vmbus_bus_init(irq);
if (ret)
goto cleanup;
return 0;
cleanup:
acpi_bus_unregister_driver(&vmbus_acpi_driver);
hv_acpi_dev = NULL;
return ret;
}
static void __exit vmbus_exit(void)
{
hv_remove_vmbus_irq();
vmbus_free_channels();
bus_unregister(&hv_bus);
hv_cleanup();
acpi_bus_unregister_driver(&vmbus_acpi_driver);
}
MODULE_LICENSE("GPL");
subsys_initcall(hv_acpi_init);
module_exit(vmbus_exit);