vmbus_drv.c 34.2 KB
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/*
 * 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>
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 *   K. Y. Srinivasan <kys@microsoft.com>
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 *
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 */
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#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

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#include <linux/init.h>
#include <linux/module.h>
#include <linux/device.h>
#include <linux/interrupt.h>
#include <linux/sysctl.h>
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#include <linux/slab.h>
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#include <linux/acpi.h>
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#include <linux/completion.h>
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#include <linux/hyperv.h>
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#include <linux/kernel_stat.h>
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#include <linux/clockchips.h>
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#include <linux/cpu.h>
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#include <asm/hyperv.h>
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#include <asm/hypervisor.h>
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#include <asm/mshyperv.h>
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#include <linux/notifier.h>
#include <linux/ptrace.h>
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#include <linux/screen_info.h>
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#include <linux/kdebug.h>
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#include "hyperv_vmbus.h"
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static struct acpi_device  *hv_acpi_dev;
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static struct tasklet_struct msg_dpc;
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static struct completion probe_event;
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static int irq;
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static void hyperv_report_panic(struct pt_regs *regs)
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{
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	static bool panic_reported;
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	/*
	 * We prefer to report panic on 'die' chain as we have proper
	 * registers to report, but if we miss it (e.g. on BUG()) we need
	 * to report it on 'panic'.
	 */
	if (panic_reported)
		return;
	panic_reported = true;
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	wrmsrl(HV_X64_MSR_CRASH_P0, regs->ip);
	wrmsrl(HV_X64_MSR_CRASH_P1, regs->ax);
	wrmsrl(HV_X64_MSR_CRASH_P2, regs->bx);
	wrmsrl(HV_X64_MSR_CRASH_P3, regs->cx);
	wrmsrl(HV_X64_MSR_CRASH_P4, regs->dx);

	/*
	 * Let Hyper-V know there is crash data available
	 */
	wrmsrl(HV_X64_MSR_CRASH_CTL, HV_CRASH_CTL_CRASH_NOTIFY);
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}

static int hyperv_panic_event(struct notifier_block *nb, unsigned long val,
			      void *args)
{
	struct pt_regs *regs;

	regs = current_pt_regs();

	hyperv_report_panic(regs);
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	return NOTIFY_DONE;
}

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static int hyperv_die_event(struct notifier_block *nb, unsigned long val,
			    void *args)
{
	struct die_args *die = (struct die_args *)args;
	struct pt_regs *regs = die->regs;

	hyperv_report_panic(regs);
	return NOTIFY_DONE;
}

static struct notifier_block hyperv_die_block = {
	.notifier_call = hyperv_die_event,
};
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static struct notifier_block hyperv_panic_block = {
	.notifier_call = hyperv_panic_event,
};

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struct resource *hyperv_mmio;
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static int vmbus_exists(void)
{
	if (hv_acpi_dev == NULL)
		return -ENODEV;

	return 0;
}

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#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]);
}

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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;
}

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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];
}

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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;
}

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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);

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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);

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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);

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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);

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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);

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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);

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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);
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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);

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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);

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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);

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static ssize_t channel_vp_mapping_show(struct device *dev,
				       struct device_attribute *dev_attr,
				       char *buf)
{
	struct hv_device *hv_dev = device_to_hv_device(dev);
	struct vmbus_channel *channel = hv_dev->channel, *cur_sc;
	unsigned long flags;
	int buf_size = PAGE_SIZE, n_written, tot_written;
	struct list_head *cur;

	if (!channel)
		return -ENODEV;

	tot_written = snprintf(buf, buf_size, "%u:%u\n",
		channel->offermsg.child_relid, channel->target_cpu);

	spin_lock_irqsave(&channel->lock, flags);

	list_for_each(cur, &channel->sc_list) {
		if (tot_written >= buf_size - 1)
			break;

		cur_sc = list_entry(cur, struct vmbus_channel, sc_list);
		n_written = scnprintf(buf + tot_written,
				     buf_size - tot_written,
				     "%u:%u\n",
				     cur_sc->offermsg.child_relid,
				     cur_sc->target_cpu);
		tot_written += n_written;
	}

	spin_unlock_irqrestore(&channel->lock, flags);

	return tot_written;
}
static DEVICE_ATTR_RO(channel_vp_mapping);

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/* Set up per device attributes in /sys/bus/vmbus/devices/<bus device> */
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static struct attribute *vmbus_attrs[] = {
	&dev_attr_id.attr,
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	&dev_attr_state.attr,
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	&dev_attr_monitor_id.attr,
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	&dev_attr_class_id.attr,
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	&dev_attr_device_id.attr,
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	&dev_attr_modalias.attr,
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	&dev_attr_server_monitor_pending.attr,
	&dev_attr_client_monitor_pending.attr,
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	&dev_attr_server_monitor_latency.attr,
	&dev_attr_client_monitor_latency.attr,
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	&dev_attr_server_monitor_conn_id.attr,
	&dev_attr_client_monitor_conn_id.attr,
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	&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,
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	&dev_attr_channel_vp_mapping.attr,
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	NULL,
};
ATTRIBUTE_GROUPS(vmbus);

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/*
 * 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
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 *
 * 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.
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 */
static int vmbus_uevent(struct device *device, struct kobj_uevent_env *env)
{
	struct hv_device *dev = device_to_hv_device(device);
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	int ret;
	char alias_name[VMBUS_ALIAS_LEN + 1];
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	print_alias_name(dev, alias_name);
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	ret = add_uevent_var(env, "MODALIAS=vmbus:%s", alias_name);
	return ret;
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}

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static const uuid_le null_guid;
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static inline bool is_null_guid(const __u8 *guid)
{
	if (memcmp(guid, &null_guid, sizeof(uuid_le)))
		return false;
	return true;
}

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/*
 * 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,
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					const __u8 *guid)
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{
	for (; !is_null_guid(id->guid); id++)
		if (!memcmp(&id->guid, guid, sizeof(uuid_le)))
			return id;

	return NULL;
}


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/*
 * 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);
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	struct hv_device *hv_dev = device_to_hv_device(device);
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	if (hv_vmbus_get_id(drv->id_table, hv_dev->dev_type.b))
		return 1;
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	return 0;
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}

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/*
 * 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);
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	struct hv_device *dev = device_to_hv_device(child_device);
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	const struct hv_vmbus_device_id *dev_id;
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	dev_id = hv_vmbus_get_id(drv->id_table, dev->dev_type.b);
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	if (drv->probe) {
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		ret = drv->probe(dev, dev_id);
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		if (ret != 0)
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			pr_err("probe failed for device %s (%d)\n",
			       dev_name(child_device), ret);
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	} else {
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		pr_err("probe not set for driver %s\n",
		       dev_name(child_device));
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		ret = -ENODEV;
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	}
	return ret;
}

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/*
 * vmbus_remove - Remove a vmbus device
 */
static int vmbus_remove(struct device *child_device)
{
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	struct hv_driver *drv;
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	struct hv_device *dev = device_to_hv_device(child_device);
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	u32 relid = dev->channel->offermsg.child_relid;
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	if (child_device->driver) {
		drv = drv_to_hv_drv(child_device->driver);
		if (drv->remove)
			drv->remove(dev);
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		else {
			hv_process_channel_removal(dev->channel, relid);
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			pr_err("remove not set for driver %s\n",
				dev_name(child_device));
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		}
	} else {
		/*
		 * We don't have a driver for this device; deal with the
		 * rescind message by removing the channel.
		 */
		hv_process_channel_removal(dev->channel, relid);
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	}
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	return 0;
}

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/*
 * vmbus_shutdown - Shutdown a vmbus device
 */
static void vmbus_shutdown(struct device *child_device)
{
	struct hv_driver *drv;
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	struct hv_device *dev = device_to_hv_device(child_device);
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	/* The device may not be attached yet */
	if (!child_device->driver)
		return;

	drv = drv_to_hv_drv(child_device->driver);

643 644
	if (drv->shutdown)
		drv->shutdown(dev);
645 646 647 648

	return;
}

649 650 651 652 653 654

/*
 * vmbus_device_release - Final callback release of the vmbus child device
 */
static void vmbus_device_release(struct device *device)
{
655
	struct hv_device *hv_dev = device_to_hv_device(device);
656

657
	kfree(hv_dev);
658 659 660

}

661
/* The one and only one */
662 663 664 665 666 667 668
static struct bus_type  hv_bus = {
	.name =		"vmbus",
	.match =		vmbus_match,
	.shutdown =		vmbus_shutdown,
	.remove =		vmbus_remove,
	.probe =		vmbus_probe,
	.uevent =		vmbus_uevent,
669
	.dev_groups =		vmbus_groups,
670 671
};

672 673 674 675 676 677 678 679 680
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;

681 682 683 684
	/* Do not process messages if we're in DISCONNECTED state */
	if (vmbus_connection.conn_state == DISCONNECTED)
		return;

685 686 687 688 689 690
	ctx = container_of(work, struct onmessage_work_context,
			   work);
	vmbus_onmessage(&ctx->msg);
	kfree(ctx);
}

691
static void hv_process_timer_expiration(struct hv_message *msg, int cpu)
692 693 694 695 696 697 698 699 700 701 702 703 704 705 706 707 708 709 710 711 712 713 714 715 716 717 718
{
	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);
	}
}

719
static void vmbus_on_msg_dpc(unsigned long data)
G
Greg Kroah-Hartman 已提交
720 721 722 723 724
{
	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;
725 726
	struct vmbus_channel_message_header *hdr;
	struct vmbus_channel_message_table_entry *entry;
727
	struct onmessage_work_context *ctx;
G
Greg Kroah-Hartman 已提交
728 729

	while (1) {
730
		if (msg->header.message_type == HVMSG_NONE)
G
Greg Kroah-Hartman 已提交
731 732
			/* no msg */
			break;
733 734 735 736 737 738 739 740 741 742

		hdr = (struct vmbus_channel_message_header *)msg->u.payload;

		if (hdr->msgtype >= CHANNELMSG_COUNT) {
			WARN_ONCE(1, "unknown msgtype=%d\n", hdr->msgtype);
			goto msg_handled;
		}

		entry = &channel_message_table[hdr->msgtype];
		if (entry->handler_type	== VMHT_BLOCKING) {
743 744
			ctx = kmalloc(sizeof(*ctx), GFP_ATOMIC);
			if (ctx == NULL)
G
Greg Kroah-Hartman 已提交
745
				continue;
746

747 748
			INIT_WORK(&ctx->work, vmbus_onmessage_work);
			memcpy(&ctx->msg, msg, sizeof(*msg));
749

750
			queue_work(vmbus_connection.work_queue, &ctx->work);
751 752
		} else
			entry->message_handler(hdr);
G
Greg Kroah-Hartman 已提交
753

754
msg_handled:
G
Greg Kroah-Hartman 已提交
755 756 757 758 759 760 761 762 763
		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
		 */
764
		mb();
G
Greg Kroah-Hartman 已提交
765 766 767 768 769 770 771 772 773 774 775 776

		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);
		}
	}
}

777
static void vmbus_isr(void)
G
Greg Kroah-Hartman 已提交
778 779 780 781 782
{
	int cpu = smp_processor_id();
	void *page_addr;
	struct hv_message *msg;
	union hv_synic_event_flags *event;
783
	bool handled = false;
G
Greg Kroah-Hartman 已提交
784

785 786
	page_addr = hv_context.synic_event_page[cpu];
	if (page_addr == NULL)
787
		return;
788 789 790

	event = (union hv_synic_event_flags *)page_addr +
					 VMBUS_MESSAGE_SINT;
791 792 793 794 795
	/*
	 * 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.
	 */
G
Greg Kroah-Hartman 已提交
796

797 798
	if ((vmbus_proto_version == VERSION_WS2008) ||
		(vmbus_proto_version == VERSION_WIN7)) {
G
Greg Kroah-Hartman 已提交
799

800 801 802 803 804 805 806 807 808 809 810 811
		/* 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.
		 */
812 813
		handled = true;
	}
814

815
	if (handled)
816
		tasklet_schedule(hv_context.event_dpc[cpu]);
817 818


819 820 821 822
	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 */
823 824 825 826 827 828
	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);
	}
829 830
}

831

832
/*
833 834 835
 * vmbus_bus_init -Main vmbus driver initialization routine.
 *
 * Here, we
836 837 838 839
 *	- initialize the vmbus driver context
 *	- invoke the vmbus hv main init routine
 *	- get the irq resource
 *	- retrieve the channel offers
840
 */
841
static int vmbus_bus_init(int irq)
842
{
843
	int ret;
844

845 846
	/* Hypervisor initialization...setup hypercall page..etc */
	ret = hv_init();
847
	if (ret != 0) {
848
		pr_err("Unable to initialize the hypervisor - 0x%x\n", ret);
849
		return ret;
850 851
	}

852
	tasklet_init(&msg_dpc, vmbus_on_msg_dpc, 0);
853

854
	ret = bus_register(&hv_bus);
855
	if (ret)
856
		goto err_cleanup;
857

858
	hv_setup_vmbus_irq(vmbus_isr);
859

860 861 862
	ret = hv_synic_alloc();
	if (ret)
		goto err_alloc;
863
	/*
864
	 * Initialize the per-cpu interrupt state and
865 866
	 * connect to the host.
	 */
867
	on_each_cpu(hv_synic_init, NULL, 1);
868
	ret = vmbus_connect();
869
	if (ret)
870
		goto err_connect;
871

872 873
	if (vmbus_proto_version > VERSION_WIN7)
		cpu_hotplug_disable();
874 875 876 877

	/*
	 * Only register if the crash MSRs are available
	 */
878
	if (ms_hyperv.misc_features & HV_FEATURE_GUEST_CRASH_MSR_AVAILABLE) {
879
		register_die_notifier(&hyperv_die_block);
880 881 882 883
		atomic_notifier_chain_register(&panic_notifier_list,
					       &hyperv_panic_block);
	}

884
	vmbus_request_offers();
885

886
	return 0;
887

888 889
err_connect:
	on_each_cpu(hv_synic_cleanup, NULL, 1);
890 891
err_alloc:
	hv_synic_free();
892
	hv_remove_vmbus_irq();
893 894 895 896 897 898 899

	bus_unregister(&hv_bus);

err_cleanup:
	hv_cleanup();

	return ret;
900 901
}

902
/**
903 904
 * __vmbus_child_driver_register() - Register a vmbus's driver
 * @hv_driver: Pointer to driver structure you want to register
905 906
 * @owner: owner module of the drv
 * @mod_name: module name string
907 908
 *
 * Registers the given driver with Linux through the 'driver_register()' call
909
 * and sets up the hyper-v vmbus handling for this driver.
910 911
 * It will return the state of the 'driver_register()' call.
 *
912
 */
913
int __vmbus_driver_register(struct hv_driver *hv_driver, struct module *owner, const char *mod_name)
914
{
915
	int ret;
916

917
	pr_info("registering driver %s\n", hv_driver->name);
918

919 920 921 922
	ret = vmbus_exists();
	if (ret < 0)
		return ret;

923 924 925 926
	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;
927

928
	ret = driver_register(&hv_driver->driver);
929

930
	return ret;
931
}
932
EXPORT_SYMBOL_GPL(__vmbus_driver_register);
933

934
/**
935
 * vmbus_driver_unregister() - Unregister a vmbus's driver
936 937
 * @hv_driver: Pointer to driver structure you want to
 *             un-register
938
 *
939 940
 * Un-register the given driver that was previous registered with a call to
 * vmbus_driver_register()
941
 */
942
void vmbus_driver_unregister(struct hv_driver *hv_driver)
943
{
944
	pr_info("unregistering driver %s\n", hv_driver->name);
945

946
	if (!vmbus_exists())
947
		driver_unregister(&hv_driver->driver);
948
}
949
EXPORT_SYMBOL_GPL(vmbus_driver_unregister);
950

951
/*
952
 * vmbus_device_create - Creates and registers a new child device
953
 * on the vmbus.
954
 */
S
stephen hemminger 已提交
955 956 957
struct hv_device *vmbus_device_create(const uuid_le *type,
				      const uuid_le *instance,
				      struct vmbus_channel *channel)
958
{
959
	struct hv_device *child_device_obj;
960

961 962
	child_device_obj = kzalloc(sizeof(struct hv_device), GFP_KERNEL);
	if (!child_device_obj) {
963
		pr_err("Unable to allocate device object for child device\n");
964 965 966
		return NULL;
	}

967
	child_device_obj->channel = channel;
968
	memcpy(&child_device_obj->dev_type, type, sizeof(uuid_le));
969
	memcpy(&child_device_obj->dev_instance, instance,
970
	       sizeof(uuid_le));
971 972 973 974 975


	return child_device_obj;
}

976
/*
977
 * vmbus_device_register - Register the child device
978
 */
979
int vmbus_device_register(struct hv_device *child_device_obj)
980
{
981
	int ret = 0;
982

983 984
	dev_set_name(&child_device_obj->device, "vmbus_%d",
		     child_device_obj->channel->id);
985

986
	child_device_obj->device.bus = &hv_bus;
987
	child_device_obj->device.parent = &hv_acpi_dev->dev;
988
	child_device_obj->device.release = vmbus_device_release;
989

990 991 992 993
	/*
	 * Register with the LDM. This will kick off the driver/device
	 * binding...which will eventually call vmbus_match() and vmbus_probe()
	 */
994
	ret = device_register(&child_device_obj->device);
995 996

	if (ret)
997
		pr_err("Unable to register child device\n");
998
	else
999
		pr_debug("child device %s registered\n",
1000
			dev_name(&child_device_obj->device));
1001 1002 1003 1004

	return ret;
}

1005
/*
1006
 * vmbus_device_unregister - Remove the specified child device
1007
 * from the vmbus.
1008
 */
1009
void vmbus_device_unregister(struct hv_device *device_obj)
1010
{
1011 1012 1013
	pr_debug("child device %s unregistered\n",
		dev_name(&device_obj->device));

1014 1015 1016 1017
	/*
	 * Kick off the process of unregistering the device.
	 * This will call vmbus_remove() and eventually vmbus_device_release()
	 */
1018
	device_unregister(&device_obj->device);
1019 1020 1021
}


1022
/*
1023
 * VMBUS is an acpi enumerated device. Get the information we
1024
 * need from DSDT.
1025
 */
1026
#define VTPM_BASE_ADDRESS 0xfed40000
1027
static acpi_status vmbus_walk_resources(struct acpi_resource *res, void *ctx)
1028
{
1029 1030 1031 1032 1033 1034
	resource_size_t start = 0;
	resource_size_t end = 0;
	struct resource *new_res;
	struct resource **old_res = &hyperv_mmio;
	struct resource **prev_res = NULL;

1035 1036 1037
	switch (res->type) {
	case ACPI_RESOURCE_TYPE_IRQ:
		irq = res->data.irq.interrupts[0];
1038 1039 1040 1041 1042 1043 1044 1045 1046 1047
		return AE_OK;

	/*
	 * "Address" descriptors are for bus windows. Ignore
	 * "memory" descriptors, which are for registers on
	 * devices.
	 */
	case ACPI_RESOURCE_TYPE_ADDRESS32:
		start = res->data.address32.address.minimum;
		end = res->data.address32.address.maximum;
G
Gerd Hoffmann 已提交
1048
		break;
1049

1050
	case ACPI_RESOURCE_TYPE_ADDRESS64:
1051 1052
		start = res->data.address64.address.minimum;
		end = res->data.address64.address.maximum;
G
Gerd Hoffmann 已提交
1053
		break;
1054 1055 1056 1057 1058

	default:
		/* Unused resource type */
		return AE_OK;

1059
	}
1060 1061 1062 1063 1064 1065 1066 1067 1068 1069 1070 1071 1072 1073 1074 1075 1076 1077 1078 1079 1080 1081 1082 1083 1084 1085 1086 1087 1088 1089 1090 1091 1092 1093 1094 1095 1096 1097
	/*
	 * Ignore ranges that are below 1MB, as they're not
	 * necessary or useful here.
	 */
	if (end < 0x100000)
		return AE_OK;

	new_res = kzalloc(sizeof(*new_res), GFP_ATOMIC);
	if (!new_res)
		return AE_NO_MEMORY;

	/* If this range overlaps the virtual TPM, truncate it. */
	if (end > VTPM_BASE_ADDRESS && start < VTPM_BASE_ADDRESS)
		end = VTPM_BASE_ADDRESS;

	new_res->name = "hyperv mmio";
	new_res->flags = IORESOURCE_MEM;
	new_res->start = start;
	new_res->end = end;

	do {
		if (!*old_res) {
			*old_res = new_res;
			break;
		}

		if ((*old_res)->end < new_res->start) {
			new_res->sibling = *old_res;
			if (prev_res)
				(*prev_res)->sibling = new_res;
			*old_res = new_res;
			break;
		}

		prev_res = old_res;
		old_res = &(*old_res)->sibling;

	} while (1);
1098 1099 1100 1101

	return AE_OK;
}

1102 1103 1104 1105 1106 1107 1108 1109 1110 1111 1112 1113 1114 1115 1116
static int vmbus_acpi_remove(struct acpi_device *device)
{
	struct resource *cur_res;
	struct resource *next_res;

	if (hyperv_mmio) {
		for (cur_res = hyperv_mmio; cur_res; cur_res = next_res) {
			next_res = cur_res->sibling;
			kfree(cur_res);
		}
	}

	return 0;
}

1117 1118 1119 1120 1121 1122 1123 1124 1125 1126 1127 1128 1129 1130 1131 1132 1133 1134 1135 1136 1137 1138 1139 1140 1141 1142 1143 1144 1145 1146 1147 1148 1149 1150 1151 1152 1153 1154 1155 1156 1157 1158 1159 1160 1161 1162 1163 1164 1165 1166 1167 1168 1169 1170 1171 1172 1173 1174 1175 1176 1177 1178 1179 1180 1181 1182 1183 1184 1185 1186 1187 1188 1189 1190 1191 1192 1193 1194 1195
/**
 * vmbus_allocate_mmio() - Pick a memory-mapped I/O range.
 * @new:		If successful, supplied a pointer to the
 *			allocated MMIO space.
 * @device_obj:		Identifies the caller
 * @min:		Minimum guest physical address of the
 *			allocation
 * @max:		Maximum guest physical address
 * @size:		Size of the range to be allocated
 * @align:		Alignment of the range to be allocated
 * @fb_overlap_ok:	Whether this allocation can be allowed
 *			to overlap the video frame buffer.
 *
 * This function walks the resources granted to VMBus by the
 * _CRS object in the ACPI namespace underneath the parent
 * "bridge" whether that's a root PCI bus in the Generation 1
 * case or a Module Device in the Generation 2 case.  It then
 * attempts to allocate from the global MMIO pool in a way that
 * matches the constraints supplied in these parameters and by
 * that _CRS.
 *
 * Return: 0 on success, -errno on failure
 */
int vmbus_allocate_mmio(struct resource **new, struct hv_device *device_obj,
			resource_size_t min, resource_size_t max,
			resource_size_t size, resource_size_t align,
			bool fb_overlap_ok)
{
	struct resource *iter;
	resource_size_t range_min, range_max, start, local_min, local_max;
	const char *dev_n = dev_name(&device_obj->device);
	u32 fb_end = screen_info.lfb_base + (screen_info.lfb_size << 1);
	int i;

	for (iter = hyperv_mmio; iter; iter = iter->sibling) {
		if ((iter->start >= max) || (iter->end <= min))
			continue;

		range_min = iter->start;
		range_max = iter->end;

		/* If this range overlaps the frame buffer, split it into
		   two tries. */
		for (i = 0; i < 2; i++) {
			local_min = range_min;
			local_max = range_max;
			if (fb_overlap_ok || (range_min >= fb_end) ||
			    (range_max <= screen_info.lfb_base)) {
				i++;
			} else {
				if ((range_min <= screen_info.lfb_base) &&
				    (range_max >= screen_info.lfb_base)) {
					/*
					 * The frame buffer is in this window,
					 * so trim this into the part that
					 * preceeds the frame buffer.
					 */
					local_max = screen_info.lfb_base - 1;
					range_min = fb_end;
				} else {
					range_min = fb_end;
					continue;
				}
			}

			start = (local_min + align - 1) & ~(align - 1);
			for (; start + size - 1 <= local_max; start += align) {
				*new = request_mem_region_exclusive(start, size,
								    dev_n);
				if (*new)
					return 0;
			}
		}
	}

	return -ENXIO;
}
EXPORT_SYMBOL_GPL(vmbus_allocate_mmio);

1196 1197 1198 1199 1200 1201 1202 1203 1204 1205 1206 1207 1208 1209 1210 1211 1212
/**
 * vmbus_cpu_number_to_vp_number() - Map CPU to VP.
 * @cpu_number: CPU number in Linux terms
 *
 * This function returns the mapping between the Linux processor
 * number and the hypervisor's virtual processor number, useful
 * in making hypercalls and such that talk about specific
 * processors.
 *
 * Return: Virtual processor number in Hyper-V terms
 */
int vmbus_cpu_number_to_vp_number(int cpu_number)
{
	return hv_context.vp_index[cpu_number];
}
EXPORT_SYMBOL_GPL(vmbus_cpu_number_to_vp_number);

1213 1214 1215
static int vmbus_acpi_add(struct acpi_device *device)
{
	acpi_status result;
1216
	int ret_val = -ENODEV;
1217
	struct acpi_device *ancestor;
1218

1219 1220
	hv_acpi_dev = device;

1221
	result = acpi_walk_resources(device->handle, METHOD_NAME__CRS,
1222
					vmbus_walk_resources, NULL);
1223

1224 1225 1226
	if (ACPI_FAILURE(result))
		goto acpi_walk_err;
	/*
1227 1228
	 * Some ancestor of the vmbus acpi device (Gen1 or Gen2
	 * firmware) is the VMOD that has the mmio ranges. Get that.
1229
	 */
1230 1231 1232
	for (ancestor = device->parent; ancestor; ancestor = ancestor->parent) {
		result = acpi_walk_resources(ancestor->handle, METHOD_NAME__CRS,
					     vmbus_walk_resources, NULL);
1233 1234

		if (ACPI_FAILURE(result))
1235 1236 1237
			continue;
		if (hyperv_mmio)
			break;
1238
	}
1239 1240 1241
	ret_val = 0;

acpi_walk_err:
1242
	complete(&probe_event);
1243 1244
	if (ret_val)
		vmbus_acpi_remove(device);
1245
	return ret_val;
1246 1247 1248 1249
}

static const struct acpi_device_id vmbus_acpi_device_ids[] = {
	{"VMBUS", 0},
1250
	{"VMBus", 0},
1251 1252 1253 1254 1255 1256 1257 1258 1259
	{"", 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,
1260
		.remove = vmbus_acpi_remove,
1261 1262 1263
	},
};

1264 1265 1266 1267 1268 1269 1270 1271 1272 1273 1274
static void hv_kexec_handler(void)
{
	int cpu;

	hv_synic_clockevents_cleanup();
	vmbus_initiate_unload();
	for_each_online_cpu(cpu)
		smp_call_function_single(cpu, hv_synic_cleanup, NULL, 1);
	hv_cleanup();
};

1275 1276 1277 1278 1279 1280 1281 1282 1283 1284 1285 1286
static void hv_crash_handler(struct pt_regs *regs)
{
	vmbus_initiate_unload();
	/*
	 * In crash handler we can't schedule synic cleanup for all CPUs,
	 * doing the cleanup for current CPU only. This should be sufficient
	 * for kdump.
	 */
	hv_synic_cleanup(NULL);
	hv_cleanup();
};

1287
static int __init hv_acpi_init(void)
1288
{
1289
	int ret, t;
1290

1291
	if (x86_hyper != &x86_hyper_ms_hyperv)
1292 1293
		return -ENODEV;

1294 1295 1296 1297 1298
	init_completion(&probe_event);

	/*
	 * Get irq resources first.
	 */
1299 1300
	ret = acpi_bus_register_driver(&vmbus_acpi_driver);

1301 1302 1303
	if (ret)
		return ret;

1304 1305 1306 1307 1308
	t = wait_for_completion_timeout(&probe_event, 5*HZ);
	if (t == 0) {
		ret = -ETIMEDOUT;
		goto cleanup;
	}
1309 1310

	if (irq <= 0) {
1311 1312
		ret = -ENODEV;
		goto cleanup;
1313 1314
	}

1315 1316
	ret = vmbus_bus_init(irq);
	if (ret)
1317 1318
		goto cleanup;

1319
	hv_setup_kexec_handler(hv_kexec_handler);
1320
	hv_setup_crash_handler(hv_crash_handler);
1321

1322 1323 1324 1325
	return 0;

cleanup:
	acpi_bus_unregister_driver(&vmbus_acpi_driver);
1326
	hv_acpi_dev = NULL;
1327
	return ret;
1328 1329
}

1330 1331
static void __exit vmbus_exit(void)
{
1332 1333
	int cpu;

1334
	hv_remove_kexec_handler();
1335
	hv_remove_crash_handler();
1336
	vmbus_connection.conn_state = DISCONNECTED;
1337
	hv_synic_clockevents_cleanup();
1338
	vmbus_disconnect();
1339
	hv_remove_vmbus_irq();
1340
	tasklet_kill(&msg_dpc);
1341
	vmbus_free_channels();
1342
	if (ms_hyperv.misc_features & HV_FEATURE_GUEST_CRASH_MSR_AVAILABLE) {
1343
		unregister_die_notifier(&hyperv_die_block);
1344 1345 1346
		atomic_notifier_chain_unregister(&panic_notifier_list,
						 &hyperv_panic_block);
	}
1347 1348
	bus_unregister(&hv_bus);
	hv_cleanup();
1349 1350
	for_each_online_cpu(cpu) {
		tasklet_kill(hv_context.event_dpc[cpu]);
1351
		smp_call_function_single(cpu, hv_synic_cleanup, NULL, 1);
1352
	}
1353
	hv_synic_free();
1354
	acpi_bus_unregister_driver(&vmbus_acpi_driver);
1355 1356
	if (vmbus_proto_version > VERSION_WIN7)
		cpu_hotplug_enable();
1357 1358
}

1359

1360
MODULE_LICENSE("GPL");
1361

1362
subsys_initcall(hv_acpi_init);
1363
module_exit(vmbus_exit);