v4.19.13 snapshot.
diff --git a/drivers/hv/vmbus_drv.c b/drivers/hv/vmbus_drv.c
new file mode 100644
index 0000000..2c6d5c7
--- /dev/null
+++ b/drivers/hv/vmbus_drv.c
@@ -0,0 +1,1944 @@
+/*
+ * 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 <linux/cpu.h>
+#include <linux/sched/task_stack.h>
+
+#include <asm/mshyperv.h>
+#include <linux/notifier.h>
+#include <linux/ptrace.h>
+#include <linux/screen_info.h>
+#include <linux/kdebug.h>
+#include <linux/efi.h>
+#include <linux/random.h>
+#include "hyperv_vmbus.h"
+
+struct vmbus_dynid {
+ struct list_head node;
+ struct hv_vmbus_device_id id;
+};
+
+static struct acpi_device *hv_acpi_dev;
+
+static struct completion probe_event;
+
+static int hyperv_cpuhp_online;
+
+static void *hv_panic_page;
+
+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, val);
+ return NOTIFY_DONE;
+}
+
+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, val);
+ return NOTIFY_DONE;
+}
+
+static struct notifier_block hyperv_die_block = {
+ .notifier_call = hyperv_die_event,
+};
+static struct notifier_block hyperv_panic_block = {
+ .notifier_call = hyperv_panic_event,
+};
+
+static const char *fb_mmio_name = "fb_range";
+static struct resource *fb_mmio;
+static struct resource *hyperv_mmio;
+static DEFINE_SEMAPHORE(hyperv_mmio_lock);
+
+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(const struct vmbus_channel *channel)
+{
+ return (u8)channel->offermsg.monitorid / 32;
+}
+
+static u8 channel_monitor_offset(const struct vmbus_channel *channel)
+{
+ return (u8)channel->offermsg.monitorid % 32;
+}
+
+static u32 channel_pending(const struct vmbus_channel *channel,
+ const 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(const struct vmbus_channel *channel,
+ const 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);
+
+#ifdef CONFIG_NUMA
+static ssize_t numa_node_show(struct device *dev,
+ struct device_attribute *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->numa_node);
+}
+static DEVICE_ATTR_RO(numa_node);
+#endif
+
+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;
+ if (hv_dev->channel->state != CHANNEL_OPENED_STATE)
+ return -EINVAL;
+ 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;
+ if (hv_dev->channel->state != CHANNEL_OPENED_STATE)
+ return -EINVAL;
+ 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;
+ if (hv_dev->channel->state != CHANNEL_OPENED_STATE)
+ return -EINVAL;
+ 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;
+ if (hv_dev->channel->state != CHANNEL_OPENED_STATE)
+ return -EINVAL;
+ 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;
+ if (hv_dev->channel->state != CHANNEL_OPENED_STATE)
+ return -EINVAL;
+ 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;
+ if (hv_dev->channel->state != CHANNEL_OPENED_STATE)
+ return -EINVAL;
+ 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;
+ if (hv_dev->channel->state != CHANNEL_OPENED_STATE)
+ return -EINVAL;
+ 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;
+ if (hv_dev->channel->state != CHANNEL_OPENED_STATE)
+ return -EINVAL;
+ 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;
+ if (hv_dev->channel->state != CHANNEL_OPENED_STATE)
+ return -EINVAL;
+ 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;
+ if (hv_dev->channel->state != CHANNEL_OPENED_STATE)
+ return -EINVAL;
+ 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);
+
+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);
+
+static ssize_t vendor_show(struct device *dev,
+ struct device_attribute *dev_attr,
+ char *buf)
+{
+ struct hv_device *hv_dev = device_to_hv_device(dev);
+ return sprintf(buf, "0x%x\n", hv_dev->vendor_id);
+}
+static DEVICE_ATTR_RO(vendor);
+
+static ssize_t device_show(struct device *dev,
+ struct device_attribute *dev_attr,
+ char *buf)
+{
+ struct hv_device *hv_dev = device_to_hv_device(dev);
+ return sprintf(buf, "0x%x\n", hv_dev->device_id);
+}
+static DEVICE_ATTR_RO(device);
+
+/* Set up per device attributes in /sys/bus/vmbus/devices/<bus device> */
+static struct attribute *vmbus_dev_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,
+#ifdef CONFIG_NUMA
+ &dev_attr_numa_node.attr,
+#endif
+ &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,
+ &dev_attr_channel_vp_mapping.attr,
+ &dev_attr_vendor.attr,
+ &dev_attr_device.attr,
+ NULL,
+};
+ATTRIBUTE_GROUPS(vmbus_dev);
+
+/*
+ * 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 uuid_le *guid)
+{
+ if (uuid_le_cmp(*guid, null_guid))
+ 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(struct hv_driver *drv,
+ const uuid_le *guid)
+{
+ const struct hv_vmbus_device_id *id = NULL;
+ struct vmbus_dynid *dynid;
+
+ /* Look at the dynamic ids first, before the static ones */
+ spin_lock(&drv->dynids.lock);
+ list_for_each_entry(dynid, &drv->dynids.list, node) {
+ if (!uuid_le_cmp(dynid->id.guid, *guid)) {
+ id = &dynid->id;
+ break;
+ }
+ }
+ spin_unlock(&drv->dynids.lock);
+
+ if (id)
+ return id;
+
+ id = drv->id_table;
+ if (id == NULL)
+ return NULL; /* empty device table */
+
+ for (; !is_null_guid(&id->guid); id++)
+ if (!uuid_le_cmp(id->guid, *guid))
+ return id;
+
+ return NULL;
+}
+
+/* vmbus_add_dynid - add a new device ID to this driver and re-probe devices */
+static int vmbus_add_dynid(struct hv_driver *drv, uuid_le *guid)
+{
+ struct vmbus_dynid *dynid;
+
+ dynid = kzalloc(sizeof(*dynid), GFP_KERNEL);
+ if (!dynid)
+ return -ENOMEM;
+
+ dynid->id.guid = *guid;
+
+ spin_lock(&drv->dynids.lock);
+ list_add_tail(&dynid->node, &drv->dynids.list);
+ spin_unlock(&drv->dynids.lock);
+
+ return driver_attach(&drv->driver);
+}
+
+static void vmbus_free_dynids(struct hv_driver *drv)
+{
+ struct vmbus_dynid *dynid, *n;
+
+ spin_lock(&drv->dynids.lock);
+ list_for_each_entry_safe(dynid, n, &drv->dynids.list, node) {
+ list_del(&dynid->node);
+ kfree(dynid);
+ }
+ spin_unlock(&drv->dynids.lock);
+}
+
+/*
+ * store_new_id - sysfs frontend to vmbus_add_dynid()
+ *
+ * Allow GUIDs to be added to an existing driver via sysfs.
+ */
+static ssize_t new_id_store(struct device_driver *driver, const char *buf,
+ size_t count)
+{
+ struct hv_driver *drv = drv_to_hv_drv(driver);
+ uuid_le guid;
+ ssize_t retval;
+
+ retval = uuid_le_to_bin(buf, &guid);
+ if (retval)
+ return retval;
+
+ if (hv_vmbus_get_id(drv, &guid))
+ return -EEXIST;
+
+ retval = vmbus_add_dynid(drv, &guid);
+ if (retval)
+ return retval;
+ return count;
+}
+static DRIVER_ATTR_WO(new_id);
+
+/*
+ * store_remove_id - remove a PCI device ID from this driver
+ *
+ * Removes a dynamic pci device ID to this driver.
+ */
+static ssize_t remove_id_store(struct device_driver *driver, const char *buf,
+ size_t count)
+{
+ struct hv_driver *drv = drv_to_hv_drv(driver);
+ struct vmbus_dynid *dynid, *n;
+ uuid_le guid;
+ ssize_t retval;
+
+ retval = uuid_le_to_bin(buf, &guid);
+ if (retval)
+ return retval;
+
+ retval = -ENODEV;
+ spin_lock(&drv->dynids.lock);
+ list_for_each_entry_safe(dynid, n, &drv->dynids.list, node) {
+ struct hv_vmbus_device_id *id = &dynid->id;
+
+ if (!uuid_le_cmp(id->guid, guid)) {
+ list_del(&dynid->node);
+ kfree(dynid);
+ retval = count;
+ break;
+ }
+ }
+ spin_unlock(&drv->dynids.lock);
+
+ return retval;
+}
+static DRIVER_ATTR_WO(remove_id);
+
+static struct attribute *vmbus_drv_attrs[] = {
+ &driver_attr_new_id.attr,
+ &driver_attr_remove_id.attr,
+ NULL,
+};
+ATTRIBUTE_GROUPS(vmbus_drv);
+
+
+/*
+ * 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);
+
+ /* The hv_sock driver handles all hv_sock offers. */
+ if (is_hvsock_channel(hv_dev->channel))
+ return drv->hvsock;
+
+ if (hv_vmbus_get_id(drv, &hv_dev->dev_type))
+ 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, &dev->dev_type);
+ 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;
+ struct hv_device *dev = device_to_hv_device(child_device);
+
+ if (child_device->driver) {
+ drv = drv_to_hv_drv(child_device->driver);
+ if (drv->remove)
+ drv->remove(dev);
+ }
+
+ 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);
+}
+
+
+/*
+ * 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);
+ struct vmbus_channel *channel = hv_dev->channel;
+
+ mutex_lock(&vmbus_connection.channel_mutex);
+ hv_process_channel_removal(channel->offermsg.child_relid);
+ mutex_unlock(&vmbus_connection.channel_mutex);
+ 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_dev_groups,
+ .drv_groups = vmbus_drv_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;
+
+ /* Do not process messages if we're in DISCONNECTED state */
+ if (vmbus_connection.conn_state == DISCONNECTED)
+ return;
+
+ 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,
+ struct hv_per_cpu_context *hv_cpu)
+{
+ struct clock_event_device *dev = hv_cpu->clk_evt;
+
+ if (dev->event_handler)
+ dev->event_handler(dev);
+
+ vmbus_signal_eom(msg, HVMSG_TIMER_EXPIRED);
+}
+
+void vmbus_on_msg_dpc(unsigned long data)
+{
+ struct hv_per_cpu_context *hv_cpu = (void *)data;
+ void *page_addr = hv_cpu->synic_message_page;
+ struct hv_message *msg = (struct hv_message *)page_addr +
+ VMBUS_MESSAGE_SINT;
+ struct vmbus_channel_message_header *hdr;
+ const struct vmbus_channel_message_table_entry *entry;
+ struct onmessage_work_context *ctx;
+ u32 message_type = msg->header.message_type;
+
+ if (message_type == HVMSG_NONE)
+ /* no msg */
+ return;
+
+ hdr = (struct vmbus_channel_message_header *)msg->u.payload;
+
+ trace_vmbus_on_msg_dpc(hdr);
+
+ 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) {
+ ctx = kmalloc(sizeof(*ctx), GFP_ATOMIC);
+ if (ctx == NULL)
+ return;
+
+ INIT_WORK(&ctx->work, vmbus_onmessage_work);
+ memcpy(&ctx->msg, msg, sizeof(*msg));
+
+ /*
+ * The host can generate a rescind message while we
+ * may still be handling the original offer. We deal with
+ * this condition by ensuring the processing is done on the
+ * same CPU.
+ */
+ switch (hdr->msgtype) {
+ case CHANNELMSG_RESCIND_CHANNELOFFER:
+ /*
+ * If we are handling the rescind message;
+ * schedule the work on the global work queue.
+ */
+ schedule_work_on(vmbus_connection.connect_cpu,
+ &ctx->work);
+ break;
+
+ case CHANNELMSG_OFFERCHANNEL:
+ atomic_inc(&vmbus_connection.offer_in_progress);
+ queue_work_on(vmbus_connection.connect_cpu,
+ vmbus_connection.work_queue,
+ &ctx->work);
+ break;
+
+ default:
+ queue_work(vmbus_connection.work_queue, &ctx->work);
+ }
+ } else
+ entry->message_handler(hdr);
+
+msg_handled:
+ vmbus_signal_eom(msg, message_type);
+}
+
+
+/*
+ * Direct callback for channels using other deferred processing
+ */
+static void vmbus_channel_isr(struct vmbus_channel *channel)
+{
+ void (*callback_fn)(void *);
+
+ callback_fn = READ_ONCE(channel->onchannel_callback);
+ if (likely(callback_fn != NULL))
+ (*callback_fn)(channel->channel_callback_context);
+}
+
+/*
+ * Schedule all channels with events pending
+ */
+static void vmbus_chan_sched(struct hv_per_cpu_context *hv_cpu)
+{
+ unsigned long *recv_int_page;
+ u32 maxbits, relid;
+
+ if (vmbus_proto_version < VERSION_WIN8) {
+ maxbits = MAX_NUM_CHANNELS_SUPPORTED;
+ recv_int_page = vmbus_connection.recv_int_page;
+ } else {
+ /*
+ * When the host is win8 and beyond, the event page
+ * can be directly checked to get the id of the channel
+ * that has the interrupt pending.
+ */
+ void *page_addr = hv_cpu->synic_event_page;
+ union hv_synic_event_flags *event
+ = (union hv_synic_event_flags *)page_addr +
+ VMBUS_MESSAGE_SINT;
+
+ maxbits = HV_EVENT_FLAGS_COUNT;
+ recv_int_page = event->flags;
+ }
+
+ if (unlikely(!recv_int_page))
+ return;
+
+ for_each_set_bit(relid, recv_int_page, maxbits) {
+ struct vmbus_channel *channel;
+
+ if (!sync_test_and_clear_bit(relid, recv_int_page))
+ continue;
+
+ /* Special case - vmbus channel protocol msg */
+ if (relid == 0)
+ continue;
+
+ rcu_read_lock();
+
+ /* Find channel based on relid */
+ list_for_each_entry_rcu(channel, &hv_cpu->chan_list, percpu_list) {
+ if (channel->offermsg.child_relid != relid)
+ continue;
+
+ if (channel->rescind)
+ continue;
+
+ trace_vmbus_chan_sched(channel);
+
+ ++channel->interrupts;
+
+ switch (channel->callback_mode) {
+ case HV_CALL_ISR:
+ vmbus_channel_isr(channel);
+ break;
+
+ case HV_CALL_BATCHED:
+ hv_begin_read(&channel->inbound);
+ /* fallthrough */
+ case HV_CALL_DIRECT:
+ tasklet_schedule(&channel->callback_event);
+ }
+ }
+
+ rcu_read_unlock();
+ }
+}
+
+static void vmbus_isr(void)
+{
+ struct hv_per_cpu_context *hv_cpu
+ = this_cpu_ptr(hv_context.cpu_context);
+ void *page_addr = hv_cpu->synic_event_page;
+ struct hv_message *msg;
+ union hv_synic_event_flags *event;
+ bool handled = false;
+
+ if (unlikely(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, event->flags))
+ 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)
+ vmbus_chan_sched(hv_cpu);
+
+ page_addr = hv_cpu->synic_message_page;
+ 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, hv_cpu);
+ else
+ tasklet_schedule(&hv_cpu->msg_dpc);
+ }
+
+ add_interrupt_randomness(HYPERVISOR_CALLBACK_VECTOR, 0);
+}
+
+/*
+ * Boolean to control whether to report panic messages over Hyper-V.
+ *
+ * It can be set via /proc/sys/kernel/hyperv/record_panic_msg
+ */
+static int sysctl_record_panic_msg = 1;
+
+/*
+ * Callback from kmsg_dump. Grab as much as possible from the end of the kmsg
+ * buffer and call into Hyper-V to transfer the data.
+ */
+static void hv_kmsg_dump(struct kmsg_dumper *dumper,
+ enum kmsg_dump_reason reason)
+{
+ size_t bytes_written;
+ phys_addr_t panic_pa;
+
+ /* We are only interested in panics. */
+ if ((reason != KMSG_DUMP_PANIC) || (!sysctl_record_panic_msg))
+ return;
+
+ panic_pa = virt_to_phys(hv_panic_page);
+
+ /*
+ * Write dump contents to the page. No need to synchronize; panic should
+ * be single-threaded.
+ */
+ kmsg_dump_get_buffer(dumper, true, hv_panic_page, PAGE_SIZE,
+ &bytes_written);
+ if (bytes_written)
+ hyperv_report_panic_msg(panic_pa, bytes_written);
+}
+
+static struct kmsg_dumper hv_kmsg_dumper = {
+ .dump = hv_kmsg_dump,
+};
+
+static struct ctl_table_header *hv_ctl_table_hdr;
+static int zero;
+static int one = 1;
+
+/*
+ * sysctl option to allow the user to control whether kmsg data should be
+ * reported to Hyper-V on panic.
+ */
+static struct ctl_table hv_ctl_table[] = {
+ {
+ .procname = "hyperv_record_panic_msg",
+ .data = &sysctl_record_panic_msg,
+ .maxlen = sizeof(int),
+ .mode = 0644,
+ .proc_handler = proc_dointvec_minmax,
+ .extra1 = &zero,
+ .extra2 = &one
+ },
+ {}
+};
+
+static struct ctl_table hv_root_table[] = {
+ {
+ .procname = "kernel",
+ .mode = 0555,
+ .child = hv_ctl_table
+ },
+ {}
+};
+
+/*
+ * vmbus_bus_init -Main vmbus driver initialization routine.
+ *
+ * Here, we
+ * - initialize the vmbus driver context
+ * - invoke the vmbus hv main init routine
+ * - retrieve the channel offers
+ */
+static int vmbus_bus_init(void)
+{
+ 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;
+ }
+
+ ret = bus_register(&hv_bus);
+ if (ret)
+ return ret;
+
+ 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.
+ */
+ ret = cpuhp_setup_state(CPUHP_AP_ONLINE_DYN, "hyperv/vmbus:online",
+ hv_synic_init, hv_synic_cleanup);
+ if (ret < 0)
+ goto err_alloc;
+ hyperv_cpuhp_online = ret;
+
+ ret = vmbus_connect();
+ if (ret)
+ goto err_connect;
+
+ /*
+ * Only register if the crash MSRs are available
+ */
+ if (ms_hyperv.misc_features & HV_FEATURE_GUEST_CRASH_MSR_AVAILABLE) {
+ u64 hyperv_crash_ctl;
+ /*
+ * Sysctl registration is not fatal, since by default
+ * reporting is enabled.
+ */
+ hv_ctl_table_hdr = register_sysctl_table(hv_root_table);
+ if (!hv_ctl_table_hdr)
+ pr_err("Hyper-V: sysctl table register error");
+
+ /*
+ * Register for panic kmsg callback only if the right
+ * capability is supported by the hypervisor.
+ */
+ hv_get_crash_ctl(hyperv_crash_ctl);
+ if (hyperv_crash_ctl & HV_CRASH_CTL_CRASH_NOTIFY_MSG) {
+ hv_panic_page = (void *)get_zeroed_page(GFP_KERNEL);
+ if (hv_panic_page) {
+ ret = kmsg_dump_register(&hv_kmsg_dumper);
+ if (ret)
+ pr_err("Hyper-V: kmsg dump register "
+ "error 0x%x\n", ret);
+ } else
+ pr_err("Hyper-V: panic message page memory "
+ "allocation failed");
+ }
+
+ register_die_notifier(&hyperv_die_block);
+ atomic_notifier_chain_register(&panic_notifier_list,
+ &hyperv_panic_block);
+ }
+
+ vmbus_request_offers();
+
+ return 0;
+
+err_connect:
+ cpuhp_remove_state(hyperv_cpuhp_online);
+err_alloc:
+ hv_synic_free();
+ hv_remove_vmbus_irq();
+
+ bus_unregister(&hv_bus);
+ free_page((unsigned long)hv_panic_page);
+ unregister_sysctl_table(hv_ctl_table_hdr);
+ hv_ctl_table_hdr = NULL;
+ return ret;
+}
+
+/**
+ * __vmbus_child_driver_register() - Register a vmbus's driver
+ * @hv_driver: 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;
+
+ spin_lock_init(&hv_driver->dynids.lock);
+ INIT_LIST_HEAD(&hv_driver->dynids.list);
+
+ ret = driver_register(&hv_driver->driver);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(__vmbus_driver_register);
+
+/**
+ * vmbus_driver_unregister() - Unregister a vmbus's driver
+ * @hv_driver: 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);
+ vmbus_free_dynids(hv_driver);
+ }
+}
+EXPORT_SYMBOL_GPL(vmbus_driver_unregister);
+
+
+/*
+ * Called when last reference to channel is gone.
+ */
+static void vmbus_chan_release(struct kobject *kobj)
+{
+ struct vmbus_channel *channel
+ = container_of(kobj, struct vmbus_channel, kobj);
+
+ kfree_rcu(channel, rcu);
+}
+
+struct vmbus_chan_attribute {
+ struct attribute attr;
+ ssize_t (*show)(const struct vmbus_channel *chan, char *buf);
+ ssize_t (*store)(struct vmbus_channel *chan,
+ const char *buf, size_t count);
+};
+#define VMBUS_CHAN_ATTR(_name, _mode, _show, _store) \
+ struct vmbus_chan_attribute chan_attr_##_name \
+ = __ATTR(_name, _mode, _show, _store)
+#define VMBUS_CHAN_ATTR_RW(_name) \
+ struct vmbus_chan_attribute chan_attr_##_name = __ATTR_RW(_name)
+#define VMBUS_CHAN_ATTR_RO(_name) \
+ struct vmbus_chan_attribute chan_attr_##_name = __ATTR_RO(_name)
+#define VMBUS_CHAN_ATTR_WO(_name) \
+ struct vmbus_chan_attribute chan_attr_##_name = __ATTR_WO(_name)
+
+static ssize_t vmbus_chan_attr_show(struct kobject *kobj,
+ struct attribute *attr, char *buf)
+{
+ const struct vmbus_chan_attribute *attribute
+ = container_of(attr, struct vmbus_chan_attribute, attr);
+ const struct vmbus_channel *chan
+ = container_of(kobj, struct vmbus_channel, kobj);
+
+ if (!attribute->show)
+ return -EIO;
+
+ if (chan->state != CHANNEL_OPENED_STATE)
+ return -EINVAL;
+
+ return attribute->show(chan, buf);
+}
+
+static const struct sysfs_ops vmbus_chan_sysfs_ops = {
+ .show = vmbus_chan_attr_show,
+};
+
+static ssize_t out_mask_show(const struct vmbus_channel *channel, char *buf)
+{
+ const struct hv_ring_buffer_info *rbi = &channel->outbound;
+
+ return sprintf(buf, "%u\n", rbi->ring_buffer->interrupt_mask);
+}
+static VMBUS_CHAN_ATTR_RO(out_mask);
+
+static ssize_t in_mask_show(const struct vmbus_channel *channel, char *buf)
+{
+ const struct hv_ring_buffer_info *rbi = &channel->inbound;
+
+ return sprintf(buf, "%u\n", rbi->ring_buffer->interrupt_mask);
+}
+static VMBUS_CHAN_ATTR_RO(in_mask);
+
+static ssize_t read_avail_show(const struct vmbus_channel *channel, char *buf)
+{
+ const struct hv_ring_buffer_info *rbi = &channel->inbound;
+
+ return sprintf(buf, "%u\n", hv_get_bytes_to_read(rbi));
+}
+static VMBUS_CHAN_ATTR_RO(read_avail);
+
+static ssize_t write_avail_show(const struct vmbus_channel *channel, char *buf)
+{
+ const struct hv_ring_buffer_info *rbi = &channel->outbound;
+
+ return sprintf(buf, "%u\n", hv_get_bytes_to_write(rbi));
+}
+static VMBUS_CHAN_ATTR_RO(write_avail);
+
+static ssize_t show_target_cpu(const struct vmbus_channel *channel, char *buf)
+{
+ return sprintf(buf, "%u\n", channel->target_cpu);
+}
+static VMBUS_CHAN_ATTR(cpu, S_IRUGO, show_target_cpu, NULL);
+
+static ssize_t channel_pending_show(const struct vmbus_channel *channel,
+ char *buf)
+{
+ return sprintf(buf, "%d\n",
+ channel_pending(channel,
+ vmbus_connection.monitor_pages[1]));
+}
+static VMBUS_CHAN_ATTR(pending, S_IRUGO, channel_pending_show, NULL);
+
+static ssize_t channel_latency_show(const struct vmbus_channel *channel,
+ char *buf)
+{
+ return sprintf(buf, "%d\n",
+ channel_latency(channel,
+ vmbus_connection.monitor_pages[1]));
+}
+static VMBUS_CHAN_ATTR(latency, S_IRUGO, channel_latency_show, NULL);
+
+static ssize_t channel_interrupts_show(const struct vmbus_channel *channel, char *buf)
+{
+ return sprintf(buf, "%llu\n", channel->interrupts);
+}
+static VMBUS_CHAN_ATTR(interrupts, S_IRUGO, channel_interrupts_show, NULL);
+
+static ssize_t channel_events_show(const struct vmbus_channel *channel, char *buf)
+{
+ return sprintf(buf, "%llu\n", channel->sig_events);
+}
+static VMBUS_CHAN_ATTR(events, S_IRUGO, channel_events_show, NULL);
+
+static ssize_t subchannel_monitor_id_show(const struct vmbus_channel *channel,
+ char *buf)
+{
+ return sprintf(buf, "%u\n", channel->offermsg.monitorid);
+}
+static VMBUS_CHAN_ATTR(monitor_id, S_IRUGO, subchannel_monitor_id_show, NULL);
+
+static ssize_t subchannel_id_show(const struct vmbus_channel *channel,
+ char *buf)
+{
+ return sprintf(buf, "%u\n",
+ channel->offermsg.offer.sub_channel_index);
+}
+static VMBUS_CHAN_ATTR_RO(subchannel_id);
+
+static struct attribute *vmbus_chan_attrs[] = {
+ &chan_attr_out_mask.attr,
+ &chan_attr_in_mask.attr,
+ &chan_attr_read_avail.attr,
+ &chan_attr_write_avail.attr,
+ &chan_attr_cpu.attr,
+ &chan_attr_pending.attr,
+ &chan_attr_latency.attr,
+ &chan_attr_interrupts.attr,
+ &chan_attr_events.attr,
+ &chan_attr_monitor_id.attr,
+ &chan_attr_subchannel_id.attr,
+ NULL
+};
+
+static struct kobj_type vmbus_chan_ktype = {
+ .sysfs_ops = &vmbus_chan_sysfs_ops,
+ .release = vmbus_chan_release,
+ .default_attrs = vmbus_chan_attrs,
+};
+
+/*
+ * vmbus_add_channel_kobj - setup a sub-directory under device/channels
+ */
+int vmbus_add_channel_kobj(struct hv_device *dev, struct vmbus_channel *channel)
+{
+ struct kobject *kobj = &channel->kobj;
+ u32 relid = channel->offermsg.child_relid;
+ int ret;
+
+ kobj->kset = dev->channels_kset;
+ ret = kobject_init_and_add(kobj, &vmbus_chan_ktype, NULL,
+ "%u", relid);
+ if (ret)
+ return ret;
+
+ kobject_uevent(kobj, KOBJ_ADD);
+
+ return 0;
+}
+
+/*
+ * 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));
+ child_device_obj->vendor_id = 0x1414; /* MSFT vendor ID */
+
+
+ return child_device_obj;
+}
+
+/*
+ * vmbus_device_register - Register the child device
+ */
+int vmbus_device_register(struct hv_device *child_device_obj)
+{
+ struct kobject *kobj = &child_device_obj->device.kobj;
+ int ret;
+
+ dev_set_name(&child_device_obj->device, "%pUl",
+ child_device_obj->channel->offermsg.offer.if_instance.b);
+
+ 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");
+ return ret;
+ }
+
+ child_device_obj->channels_kset = kset_create_and_add("channels",
+ NULL, kobj);
+ if (!child_device_obj->channels_kset) {
+ ret = -ENOMEM;
+ goto err_dev_unregister;
+ }
+
+ ret = vmbus_add_channel_kobj(child_device_obj,
+ child_device_obj->channel);
+ if (ret) {
+ pr_err("Unable to register primary channeln");
+ goto err_kset_unregister;
+ }
+
+ return 0;
+
+err_kset_unregister:
+ kset_unregister(child_device_obj->channels_kset);
+
+err_dev_unregister:
+ device_unregister(&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));
+
+ kset_unregister(device_obj->channels_kset);
+
+ /*
+ * 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 information we
+ * need from DSDT.
+ */
+#define VTPM_BASE_ADDRESS 0xfed40000
+static acpi_status vmbus_walk_resources(struct acpi_resource *res, void *ctx)
+{
+ 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;
+
+ switch (res->type) {
+
+ /*
+ * "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;
+ break;
+
+ case ACPI_RESOURCE_TYPE_ADDRESS64:
+ start = res->data.address64.address.minimum;
+ end = res->data.address64.address.maximum;
+ break;
+
+ default:
+ /* Unused resource type */
+ return AE_OK;
+
+ }
+ /*
+ * 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;
+
+ /*
+ * If two ranges are adjacent, merge them.
+ */
+ do {
+ if (!*old_res) {
+ *old_res = new_res;
+ break;
+ }
+
+ if (((*old_res)->end + 1) == new_res->start) {
+ (*old_res)->end = new_res->end;
+ kfree(new_res);
+ break;
+ }
+
+ if ((*old_res)->start == new_res->end + 1) {
+ (*old_res)->start = new_res->start;
+ kfree(new_res);
+ break;
+ }
+
+ if ((*old_res)->start > new_res->end) {
+ 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);
+
+ return AE_OK;
+}
+
+static int vmbus_acpi_remove(struct acpi_device *device)
+{
+ struct resource *cur_res;
+ struct resource *next_res;
+
+ if (hyperv_mmio) {
+ if (fb_mmio) {
+ __release_region(hyperv_mmio, fb_mmio->start,
+ resource_size(fb_mmio));
+ fb_mmio = NULL;
+ }
+
+ for (cur_res = hyperv_mmio; cur_res; cur_res = next_res) {
+ next_res = cur_res->sibling;
+ kfree(cur_res);
+ }
+ }
+
+ return 0;
+}
+
+static void vmbus_reserve_fb(void)
+{
+ int size;
+ /*
+ * Make a claim for the frame buffer in the resource tree under the
+ * first node, which will be the one below 4GB. The length seems to
+ * be underreported, particularly in a Generation 1 VM. So start out
+ * reserving a larger area and make it smaller until it succeeds.
+ */
+
+ if (screen_info.lfb_base) {
+ if (efi_enabled(EFI_BOOT))
+ size = max_t(__u32, screen_info.lfb_size, 0x800000);
+ else
+ size = max_t(__u32, screen_info.lfb_size, 0x4000000);
+
+ for (; !fb_mmio && (size >= 0x100000); size >>= 1) {
+ fb_mmio = __request_region(hyperv_mmio,
+ screen_info.lfb_base, size,
+ fb_mmio_name, 0);
+ }
+ }
+}
+
+/**
+ * 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, *shadow;
+ resource_size_t range_min, range_max, start;
+ const char *dev_n = dev_name(&device_obj->device);
+ int retval;
+
+ retval = -ENXIO;
+ down(&hyperv_mmio_lock);
+
+ /*
+ * If overlaps with frame buffers are allowed, then first attempt to
+ * make the allocation from within the reserved region. Because it
+ * is already reserved, no shadow allocation is necessary.
+ */
+ if (fb_overlap_ok && fb_mmio && !(min > fb_mmio->end) &&
+ !(max < fb_mmio->start)) {
+
+ range_min = fb_mmio->start;
+ range_max = fb_mmio->end;
+ start = (range_min + align - 1) & ~(align - 1);
+ for (; start + size - 1 <= range_max; start += align) {
+ *new = request_mem_region_exclusive(start, size, dev_n);
+ if (*new) {
+ retval = 0;
+ goto exit;
+ }
+ }
+ }
+
+ for (iter = hyperv_mmio; iter; iter = iter->sibling) {
+ if ((iter->start >= max) || (iter->end <= min))
+ continue;
+
+ range_min = iter->start;
+ range_max = iter->end;
+ start = (range_min + align - 1) & ~(align - 1);
+ for (; start + size - 1 <= range_max; start += align) {
+ shadow = __request_region(iter, start, size, NULL,
+ IORESOURCE_BUSY);
+ if (!shadow)
+ continue;
+
+ *new = request_mem_region_exclusive(start, size, dev_n);
+ if (*new) {
+ shadow->name = (char *)*new;
+ retval = 0;
+ goto exit;
+ }
+
+ __release_region(iter, start, size);
+ }
+ }
+
+exit:
+ up(&hyperv_mmio_lock);
+ return retval;
+}
+EXPORT_SYMBOL_GPL(vmbus_allocate_mmio);
+
+/**
+ * vmbus_free_mmio() - Free a memory-mapped I/O range.
+ * @start: Base address of region to release.
+ * @size: Size of the range to be allocated
+ *
+ * This function releases anything requested by
+ * vmbus_mmio_allocate().
+ */
+void vmbus_free_mmio(resource_size_t start, resource_size_t size)
+{
+ struct resource *iter;
+
+ down(&hyperv_mmio_lock);
+ for (iter = hyperv_mmio; iter; iter = iter->sibling) {
+ if ((iter->start >= start + size) || (iter->end <= start))
+ continue;
+
+ __release_region(iter, start, size);
+ }
+ release_mem_region(start, size);
+ up(&hyperv_mmio_lock);
+
+}
+EXPORT_SYMBOL_GPL(vmbus_free_mmio);
+
+static int vmbus_acpi_add(struct acpi_device *device)
+{
+ acpi_status result;
+ int ret_val = -ENODEV;
+ struct acpi_device *ancestor;
+
+ 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;
+ /*
+ * Some ancestor of the vmbus acpi device (Gen1 or Gen2
+ * firmware) is the VMOD that has the mmio ranges. Get that.
+ */
+ for (ancestor = device->parent; ancestor; ancestor = ancestor->parent) {
+ result = acpi_walk_resources(ancestor->handle, METHOD_NAME__CRS,
+ vmbus_walk_resources, NULL);
+
+ if (ACPI_FAILURE(result))
+ continue;
+ if (hyperv_mmio) {
+ vmbus_reserve_fb();
+ break;
+ }
+ }
+ ret_val = 0;
+
+acpi_walk_err:
+ complete(&probe_event);
+ if (ret_val)
+ vmbus_acpi_remove(device);
+ 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,
+ .remove = vmbus_acpi_remove,
+ },
+};
+
+static void hv_kexec_handler(void)
+{
+ hv_synic_clockevents_cleanup();
+ vmbus_initiate_unload(false);
+ vmbus_connection.conn_state = DISCONNECTED;
+ /* Make sure conn_state is set as hv_synic_cleanup checks for it */
+ mb();
+ cpuhp_remove_state(hyperv_cpuhp_online);
+ hyperv_cleanup();
+};
+
+static void hv_crash_handler(struct pt_regs *regs)
+{
+ vmbus_initiate_unload(true);
+ /*
+ * 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.
+ */
+ vmbus_connection.conn_state = DISCONNECTED;
+ hv_synic_cleanup(smp_processor_id());
+ hyperv_cleanup();
+};
+
+static int __init hv_acpi_init(void)
+{
+ int ret, t;
+
+ if (!hv_is_hyperv_initialized())
+ return -ENODEV;
+
+ init_completion(&probe_event);
+
+ /*
+ * Get ACPI 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;
+ }
+
+ ret = vmbus_bus_init();
+ if (ret)
+ goto cleanup;
+
+ hv_setup_kexec_handler(hv_kexec_handler);
+ hv_setup_crash_handler(hv_crash_handler);
+
+ return 0;
+
+cleanup:
+ acpi_bus_unregister_driver(&vmbus_acpi_driver);
+ hv_acpi_dev = NULL;
+ return ret;
+}
+
+static void __exit vmbus_exit(void)
+{
+ int cpu;
+
+ hv_remove_kexec_handler();
+ hv_remove_crash_handler();
+ vmbus_connection.conn_state = DISCONNECTED;
+ hv_synic_clockevents_cleanup();
+ vmbus_disconnect();
+ hv_remove_vmbus_irq();
+ for_each_online_cpu(cpu) {
+ struct hv_per_cpu_context *hv_cpu
+ = per_cpu_ptr(hv_context.cpu_context, cpu);
+
+ tasklet_kill(&hv_cpu->msg_dpc);
+ }
+ vmbus_free_channels();
+
+ if (ms_hyperv.misc_features & HV_FEATURE_GUEST_CRASH_MSR_AVAILABLE) {
+ kmsg_dump_unregister(&hv_kmsg_dumper);
+ unregister_die_notifier(&hyperv_die_block);
+ atomic_notifier_chain_unregister(&panic_notifier_list,
+ &hyperv_panic_block);
+ }
+
+ free_page((unsigned long)hv_panic_page);
+ unregister_sysctl_table(hv_ctl_table_hdr);
+ hv_ctl_table_hdr = NULL;
+ bus_unregister(&hv_bus);
+
+ cpuhp_remove_state(hyperv_cpuhp_online);
+ hv_synic_free();
+ acpi_bus_unregister_driver(&vmbus_acpi_driver);
+}
+
+
+MODULE_LICENSE("GPL");
+
+subsys_initcall(hv_acpi_init);
+module_exit(vmbus_exit);