| // SPDX-License-Identifier: GPL-2.0-only |
| /* |
| * Copyright (c) 2009, Microsoft Corporation. |
| * |
| * 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 <linux/delay.h> |
| #include <linux/notifier.h> |
| #include <linux/panic_notifier.h> |
| #include <linux/ptrace.h> |
| #include <linux/screen_info.h> |
| #include <linux/kdebug.h> |
| #include <linux/efi.h> |
| #include <linux/random.h> |
| #include <linux/kernel.h> |
| #include <linux/syscore_ops.h> |
| #include <linux/dma-map-ops.h> |
| #include <clocksource/hyperv_timer.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 long __percpu *vmbus_evt; |
| |
| /* Values parsed from ACPI DSDT */ |
| int vmbus_irq; |
| int vmbus_interrupt; |
| |
| /* |
| * 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; |
| |
| static int hyperv_report_reg(void) |
| { |
| return !sysctl_record_panic_msg || !hv_panic_page; |
| } |
| |
| static int hyperv_panic_event(struct notifier_block *nb, unsigned long val, |
| void *args) |
| { |
| struct pt_regs *regs; |
| |
| vmbus_initiate_unload(true); |
| |
| /* |
| * Hyper-V should be notified only once about a panic. If we will be |
| * doing hv_kmsg_dump() with kmsg data later, don't do the notification |
| * here. |
| */ |
| if (ms_hyperv.misc_features & HV_FEATURE_GUEST_CRASH_MSR_AVAILABLE |
| && hyperv_report_reg()) { |
| regs = current_pt_regs(); |
| hyperv_report_panic(regs, val, false); |
| } |
| return NOTIFY_DONE; |
| } |
| |
| static int hyperv_die_event(struct notifier_block *nb, unsigned long val, |
| void *args) |
| { |
| struct die_args *die = args; |
| struct pt_regs *regs = die->regs; |
| |
| /* Don't notify Hyper-V if the die event is other than oops */ |
| if (val != DIE_OOPS) |
| return NOTIFY_DONE; |
| |
| /* |
| * Hyper-V should be notified only once about a panic. If we will be |
| * doing hv_kmsg_dump() with kmsg data later, don't do the notification |
| * here. |
| */ |
| if (hyperv_report_reg()) |
| hyperv_report_panic(regs, val, true); |
| 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_MUTEX(hyperv_mmio_lock); |
| |
| static int vmbus_exists(void) |
| { |
| if (hv_acpi_dev == NULL) |
| return -ENODEV; |
| |
| return 0; |
| } |
| |
| 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); |
| } |
| 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); |
| } |
| 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); |
| |
| return sprintf(buf, "vmbus:%*phN\n", UUID_SIZE, &hv_dev->dev_type); |
| } |
| 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", cpu_to_node(hv_dev->channel->target_cpu)); |
| } |
| 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[0])); |
| } |
| 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; |
| int ret; |
| |
| if (!hv_dev->channel) |
| return -ENODEV; |
| |
| ret = hv_ringbuffer_get_debuginfo(&hv_dev->channel->outbound, |
| &outbound); |
| if (ret < 0) |
| return ret; |
| |
| 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; |
| int ret; |
| |
| if (!hv_dev->channel) |
| return -ENODEV; |
| |
| ret = hv_ringbuffer_get_debuginfo(&hv_dev->channel->outbound, |
| &outbound); |
| if (ret < 0) |
| return ret; |
| 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; |
| int ret; |
| |
| if (!hv_dev->channel) |
| return -ENODEV; |
| |
| ret = hv_ringbuffer_get_debuginfo(&hv_dev->channel->outbound, |
| &outbound); |
| if (ret < 0) |
| return ret; |
| 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; |
| int ret; |
| |
| if (!hv_dev->channel) |
| return -ENODEV; |
| |
| ret = hv_ringbuffer_get_debuginfo(&hv_dev->channel->outbound, |
| &outbound); |
| if (ret < 0) |
| return ret; |
| 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; |
| int ret; |
| |
| if (!hv_dev->channel) |
| return -ENODEV; |
| |
| ret = hv_ringbuffer_get_debuginfo(&hv_dev->channel->outbound, |
| &outbound); |
| if (ret < 0) |
| return ret; |
| 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; |
| int ret; |
| |
| if (!hv_dev->channel) |
| return -ENODEV; |
| |
| ret = hv_ringbuffer_get_debuginfo(&hv_dev->channel->inbound, &inbound); |
| if (ret < 0) |
| return ret; |
| |
| 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; |
| int ret; |
| |
| if (!hv_dev->channel) |
| return -ENODEV; |
| |
| ret = hv_ringbuffer_get_debuginfo(&hv_dev->channel->inbound, &inbound); |
| if (ret < 0) |
| return ret; |
| |
| 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; |
| int ret; |
| |
| if (!hv_dev->channel) |
| return -ENODEV; |
| |
| ret = hv_ringbuffer_get_debuginfo(&hv_dev->channel->inbound, &inbound); |
| if (ret < 0) |
| return ret; |
| |
| 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; |
| int ret; |
| |
| if (!hv_dev->channel) |
| return -ENODEV; |
| |
| ret = hv_ringbuffer_get_debuginfo(&hv_dev->channel->inbound, &inbound); |
| if (ret < 0) |
| return ret; |
| |
| 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; |
| int ret; |
| |
| if (!hv_dev->channel) |
| return -ENODEV; |
| |
| ret = hv_ringbuffer_get_debuginfo(&hv_dev->channel->inbound, &inbound); |
| if (ret < 0) |
| return ret; |
| |
| 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; |
| int buf_size = PAGE_SIZE, n_written, tot_written; |
| struct list_head *cur; |
| |
| if (!channel) |
| return -ENODEV; |
| |
| mutex_lock(&vmbus_connection.channel_mutex); |
| |
| tot_written = snprintf(buf, buf_size, "%u:%u\n", |
| channel->offermsg.child_relid, channel->target_cpu); |
| |
| 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; |
| } |
| |
| mutex_unlock(&vmbus_connection.channel_mutex); |
| |
| 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); |
| |
| static ssize_t driver_override_store(struct device *dev, |
| struct device_attribute *attr, |
| const char *buf, size_t count) |
| { |
| struct hv_device *hv_dev = device_to_hv_device(dev); |
| int ret; |
| |
| ret = driver_set_override(dev, &hv_dev->driver_override, buf, count); |
| if (ret) |
| return ret; |
| |
| return count; |
| } |
| |
| static ssize_t driver_override_show(struct device *dev, |
| struct device_attribute *attr, char *buf) |
| { |
| struct hv_device *hv_dev = device_to_hv_device(dev); |
| ssize_t len; |
| |
| device_lock(dev); |
| len = snprintf(buf, PAGE_SIZE, "%s\n", hv_dev->driver_override); |
| device_unlock(dev); |
| |
| return len; |
| } |
| static DEVICE_ATTR_RW(driver_override); |
| |
| /* 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, |
| &dev_attr_driver_override.attr, |
| NULL, |
| }; |
| |
| /* |
| * Device-level attribute_group callback function. Returns the permission for |
| * each attribute, and returns 0 if an attribute is not visible. |
| */ |
| static umode_t vmbus_dev_attr_is_visible(struct kobject *kobj, |
| struct attribute *attr, int idx) |
| { |
| struct device *dev = kobj_to_dev(kobj); |
| const struct hv_device *hv_dev = device_to_hv_device(dev); |
| |
| /* Hide the monitor attributes if the monitor mechanism is not used. */ |
| if (!hv_dev->channel->offermsg.monitor_allocated && |
| (attr == &dev_attr_monitor_id.attr || |
| attr == &dev_attr_server_monitor_pending.attr || |
| attr == &dev_attr_client_monitor_pending.attr || |
| attr == &dev_attr_server_monitor_latency.attr || |
| attr == &dev_attr_client_monitor_latency.attr || |
| attr == &dev_attr_server_monitor_conn_id.attr || |
| attr == &dev_attr_client_monitor_conn_id.attr)) |
| return 0; |
| |
| return attr->mode; |
| } |
| |
| static const struct attribute_group vmbus_dev_group = { |
| .attrs = vmbus_dev_attrs, |
| .is_visible = vmbus_dev_attr_is_visible |
| }; |
| __ATTRIBUTE_GROUPS(vmbus_dev); |
| |
| /* Set up the attribute for /sys/bus/vmbus/hibernation */ |
| static ssize_t hibernation_show(struct bus_type *bus, char *buf) |
| { |
| return sprintf(buf, "%d\n", !!hv_is_hibernation_supported()); |
| } |
| |
| static BUS_ATTR_RO(hibernation); |
| |
| static struct attribute *vmbus_bus_attrs[] = { |
| &bus_attr_hibernation.attr, |
| NULL, |
| }; |
| static const struct attribute_group vmbus_bus_group = { |
| .attrs = vmbus_bus_attrs, |
| }; |
| __ATTRIBUTE_GROUPS(vmbus_bus); |
| |
| /* |
| * 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); |
| const char *format = "MODALIAS=vmbus:%*phN"; |
| |
| return add_uevent_var(env, format, UUID_SIZE, &dev->dev_type); |
| } |
| |
| static const struct hv_vmbus_device_id * |
| hv_vmbus_dev_match(const struct hv_vmbus_device_id *id, const guid_t *guid) |
| { |
| if (id == NULL) |
| return NULL; /* empty device table */ |
| |
| for (; !guid_is_null(&id->guid); id++) |
| if (guid_equal(&id->guid, guid)) |
| return id; |
| |
| return NULL; |
| } |
| |
| static const struct hv_vmbus_device_id * |
| hv_vmbus_dynid_match(struct hv_driver *drv, const guid_t *guid) |
| { |
| const struct hv_vmbus_device_id *id = NULL; |
| struct vmbus_dynid *dynid; |
| |
| spin_lock(&drv->dynids.lock); |
| list_for_each_entry(dynid, &drv->dynids.list, node) { |
| if (guid_equal(&dynid->id.guid, guid)) { |
| id = &dynid->id; |
| break; |
| } |
| } |
| spin_unlock(&drv->dynids.lock); |
| |
| return id; |
| } |
| |
| static const struct hv_vmbus_device_id vmbus_device_null; |
| |
| /* |
| * 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, |
| struct hv_device *dev) |
| { |
| const guid_t *guid = &dev->dev_type; |
| const struct hv_vmbus_device_id *id; |
| |
| /* When driver_override is set, only bind to the matching driver */ |
| if (dev->driver_override && strcmp(dev->driver_override, drv->name)) |
| return NULL; |
| |
| /* Look at the dynamic ids first, before the static ones */ |
| id = hv_vmbus_dynid_match(drv, guid); |
| if (!id) |
| id = hv_vmbus_dev_match(drv->id_table, guid); |
| |
| /* driver_override will always match, send a dummy id */ |
| if (!id && dev->driver_override) |
| id = &vmbus_device_null; |
| |
| return id; |
| } |
| |
| /* vmbus_add_dynid - add a new device ID to this driver and re-probe devices */ |
| static int vmbus_add_dynid(struct hv_driver *drv, guid_t *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); |
| guid_t guid; |
| ssize_t retval; |
| |
| retval = guid_parse(buf, &guid); |
| if (retval) |
| return retval; |
| |
| if (hv_vmbus_dynid_match(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; |
| guid_t guid; |
| ssize_t retval; |
| |
| retval = guid_parse(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 (guid_equal(&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)) |
| 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); |
| 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_dma_configure -- Configure DMA coherence for VMbus device |
| */ |
| static int vmbus_dma_configure(struct device *child_device) |
| { |
| /* |
| * On ARM64, propagate the DMA coherence setting from the top level |
| * VMbus ACPI device to the child VMbus device being added here. |
| * On x86/x64 coherence is assumed and these calls have no effect. |
| */ |
| hv_setup_dma_ops(child_device, |
| device_get_dma_attr(&hv_acpi_dev->dev) == DEV_DMA_COHERENT); |
| return 0; |
| } |
| |
| /* |
| * vmbus_remove - Remove a vmbus device |
| */ |
| static void 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); |
| } |
| } |
| |
| /* |
| * 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); |
| } |
| |
| #ifdef CONFIG_PM_SLEEP |
| /* |
| * vmbus_suspend - Suspend a vmbus device |
| */ |
| static int vmbus_suspend(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 0; |
| |
| drv = drv_to_hv_drv(child_device->driver); |
| if (!drv->suspend) |
| return -EOPNOTSUPP; |
| |
| return drv->suspend(dev); |
| } |
| |
| /* |
| * vmbus_resume - Resume a vmbus device |
| */ |
| static int vmbus_resume(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 0; |
| |
| drv = drv_to_hv_drv(child_device->driver); |
| if (!drv->resume) |
| return -EOPNOTSUPP; |
| |
| return drv->resume(dev); |
| } |
| #else |
| #define vmbus_suspend NULL |
| #define vmbus_resume NULL |
| #endif /* CONFIG_PM_SLEEP */ |
| |
| /* |
| * 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; |
| |
| hv_debug_rm_dev_dir(hv_dev); |
| |
| mutex_lock(&vmbus_connection.channel_mutex); |
| hv_process_channel_removal(channel); |
| mutex_unlock(&vmbus_connection.channel_mutex); |
| kfree(hv_dev); |
| } |
| |
| /* |
| * Note: we must use the "noirq" ops: see the comment before vmbus_bus_pm. |
| * |
| * suspend_noirq/resume_noirq are set to NULL to support Suspend-to-Idle: we |
| * shouldn't suspend the vmbus devices upon Suspend-to-Idle, otherwise there |
| * is no way to wake up a Generation-2 VM. |
| * |
| * The other 4 ops are for hibernation. |
| */ |
| |
| static const struct dev_pm_ops vmbus_pm = { |
| .suspend_noirq = NULL, |
| .resume_noirq = NULL, |
| .freeze_noirq = vmbus_suspend, |
| .thaw_noirq = vmbus_resume, |
| .poweroff_noirq = vmbus_suspend, |
| .restore_noirq = vmbus_resume, |
| }; |
| |
| /* 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, |
| .dma_configure = vmbus_dma_configure, |
| .dev_groups = vmbus_dev_groups, |
| .drv_groups = vmbus_drv_groups, |
| .bus_groups = vmbus_bus_groups, |
| .pm = &vmbus_pm, |
| }; |
| |
| struct onmessage_work_context { |
| struct work_struct work; |
| struct { |
| struct hv_message_header header; |
| u8 payload[]; |
| } 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((struct vmbus_channel_message_header *) |
| &ctx->msg.payload); |
| kfree(ctx); |
| } |
| |
| 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_copy, *msg = (struct hv_message *)page_addr + |
| VMBUS_MESSAGE_SINT; |
| struct vmbus_channel_message_header *hdr; |
| enum vmbus_channel_message_type msgtype; |
| const struct vmbus_channel_message_table_entry *entry; |
| struct onmessage_work_context *ctx; |
| __u8 payload_size; |
| u32 message_type; |
| |
| /* |
| * 'enum vmbus_channel_message_type' is supposed to always be 'u32' as |
| * it is being used in 'struct vmbus_channel_message_header' definition |
| * which is supposed to match hypervisor ABI. |
| */ |
| BUILD_BUG_ON(sizeof(enum vmbus_channel_message_type) != sizeof(u32)); |
| |
| /* |
| * Since the message is in memory shared with the host, an erroneous or |
| * malicious Hyper-V could modify the message while vmbus_on_msg_dpc() |
| * or individual message handlers are executing; to prevent this, copy |
| * the message into private memory. |
| */ |
| memcpy(&msg_copy, msg, sizeof(struct hv_message)); |
| |
| message_type = msg_copy.header.message_type; |
| if (message_type == HVMSG_NONE) |
| /* no msg */ |
| return; |
| |
| hdr = (struct vmbus_channel_message_header *)msg_copy.u.payload; |
| msgtype = hdr->msgtype; |
| |
| trace_vmbus_on_msg_dpc(hdr); |
| |
| if (msgtype >= CHANNELMSG_COUNT) { |
| WARN_ONCE(1, "unknown msgtype=%d\n", msgtype); |
| goto msg_handled; |
| } |
| |
| payload_size = msg_copy.header.payload_size; |
| if (payload_size > HV_MESSAGE_PAYLOAD_BYTE_COUNT) { |
| WARN_ONCE(1, "payload size is too large (%d)\n", payload_size); |
| goto msg_handled; |
| } |
| |
| entry = &channel_message_table[msgtype]; |
| |
| if (!entry->message_handler) |
| goto msg_handled; |
| |
| if (payload_size < entry->min_payload_len) { |
| WARN_ONCE(1, "message too short: msgtype=%d len=%d\n", msgtype, payload_size); |
| goto msg_handled; |
| } |
| |
| if (entry->handler_type == VMHT_BLOCKING) { |
| ctx = kmalloc(struct_size(ctx, msg.payload, payload_size), GFP_ATOMIC); |
| if (ctx == NULL) |
| return; |
| |
| INIT_WORK(&ctx->work, vmbus_onmessage_work); |
| memcpy(&ctx->msg, &msg_copy, sizeof(msg->header) + payload_size); |
| |
| /* |
| * The host can generate a rescind message while we |
| * may still be handling the original offer. We deal with |
| * this condition by relying on the synchronization provided |
| * by offer_in_progress and by channel_mutex. See also the |
| * inline comments in vmbus_onoffer_rescind(). |
| */ |
| switch (msgtype) { |
| case CHANNELMSG_RESCIND_CHANNELOFFER: |
| /* |
| * If we are handling the rescind message; |
| * schedule the work on the global work queue. |
| * |
| * The OFFER message and the RESCIND message should |
| * not be handled by the same serialized work queue, |
| * because the OFFER handler may call vmbus_open(), |
| * which tries to open the channel by sending an |
| * OPEN_CHANNEL message to the host and waits for |
| * the host's response; however, if the host has |
| * rescinded the channel before it receives the |
| * OPEN_CHANNEL message, the host just silently |
| * ignores the OPEN_CHANNEL message; as a result, |
| * the guest's OFFER handler hangs for ever, if we |
| * handle the RESCIND message in the same serialized |
| * work queue: the RESCIND handler can not start to |
| * run before the OFFER handler finishes. |
| */ |
| schedule_work(&ctx->work); |
| break; |
| |
| case CHANNELMSG_OFFERCHANNEL: |
| /* |
| * The host sends the offer message of a given channel |
| * before sending the rescind message of the same |
| * channel. These messages are sent to the guest's |
| * connect CPU; the guest then starts processing them |
| * in the tasklet handler on this CPU: |
| * |
| * VMBUS_CONNECT_CPU |
| * |
| * [vmbus_on_msg_dpc()] |
| * atomic_inc() // CHANNELMSG_OFFERCHANNEL |
| * queue_work() |
| * ... |
| * [vmbus_on_msg_dpc()] |
| * schedule_work() // CHANNELMSG_RESCIND_CHANNELOFFER |
| * |
| * We rely on the memory-ordering properties of the |
| * queue_work() and schedule_work() primitives, which |
| * guarantee that the atomic increment will be visible |
| * to the CPUs which will execute the offer & rescind |
| * works by the time these works will start execution. |
| */ |
| atomic_inc(&vmbus_connection.offer_in_progress); |
| fallthrough; |
| |
| default: |
| queue_work(vmbus_connection.work_queue, &ctx->work); |
| } |
| } else |
| entry->message_handler(hdr); |
| |
| msg_handled: |
| vmbus_signal_eom(msg, message_type); |
| } |
| |
| #ifdef CONFIG_PM_SLEEP |
| /* |
| * Fake RESCIND_CHANNEL messages to clean up hv_sock channels by force for |
| * hibernation, because hv_sock connections can not persist across hibernation. |
| */ |
| static void vmbus_force_channel_rescinded(struct vmbus_channel *channel) |
| { |
| struct onmessage_work_context *ctx; |
| struct vmbus_channel_rescind_offer *rescind; |
| |
| WARN_ON(!is_hvsock_channel(channel)); |
| |
| /* |
| * Allocation size is small and the allocation should really not fail, |
| * otherwise the state of the hv_sock connections ends up in limbo. |
| */ |
| ctx = kzalloc(sizeof(*ctx) + sizeof(*rescind), |
| GFP_KERNEL | __GFP_NOFAIL); |
| |
| /* |
| * So far, these are not really used by Linux. Just set them to the |
| * reasonable values conforming to the definitions of the fields. |
| */ |
| ctx->msg.header.message_type = 1; |
| ctx->msg.header.payload_size = sizeof(*rescind); |
| |
| /* These values are actually used by Linux. */ |
| rescind = (struct vmbus_channel_rescind_offer *)ctx->msg.payload; |
| rescind->header.msgtype = CHANNELMSG_RESCIND_CHANNELOFFER; |
| rescind->child_relid = channel->offermsg.child_relid; |
| |
| INIT_WORK(&ctx->work, vmbus_onmessage_work); |
| |
| queue_work(vmbus_connection.work_queue, &ctx->work); |
| } |
| #endif /* CONFIG_PM_SLEEP */ |
| |
| /* |
| * 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; |
| |
| /* |
| * 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) { |
| void (*callback_fn)(void *context); |
| 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; |
| |
| /* |
| * Pairs with the kfree_rcu() in vmbus_chan_release(). |
| * Guarantees that the channel data structure doesn't |
| * get freed while the channel pointer below is being |
| * dereferenced. |
| */ |
| rcu_read_lock(); |
| |
| /* Find channel based on relid */ |
| channel = relid2channel(relid); |
| if (channel == NULL) |
| goto sched_unlock_rcu; |
| |
| if (channel->rescind) |
| goto sched_unlock_rcu; |
| |
| /* |
| * Make sure that the ring buffer data structure doesn't get |
| * freed while we dereference the ring buffer pointer. Test |
| * for the channel's onchannel_callback being NULL within a |
| * sched_lock critical section. See also the inline comments |
| * in vmbus_reset_channel_cb(). |
| */ |
| spin_lock(&channel->sched_lock); |
| |
| callback_fn = channel->onchannel_callback; |
| if (unlikely(callback_fn == NULL)) |
| goto sched_unlock; |
| |
| trace_vmbus_chan_sched(channel); |
| |
| ++channel->interrupts; |
| |
| switch (channel->callback_mode) { |
| case HV_CALL_ISR: |
| (*callback_fn)(channel->channel_callback_context); |
| break; |
| |
| case HV_CALL_BATCHED: |
| hv_begin_read(&channel->inbound); |
| fallthrough; |
| case HV_CALL_DIRECT: |
| tasklet_schedule(&channel->callback_event); |
| } |
| |
| sched_unlock: |
| spin_unlock(&channel->sched_lock); |
| sched_unlock_rcu: |
| 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; |
| struct hv_message *msg; |
| |
| 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_stimer0_isr(); |
| vmbus_signal_eom(msg, HVMSG_TIMER_EXPIRED); |
| } else |
| tasklet_schedule(&hv_cpu->msg_dpc); |
| } |
| |
| add_interrupt_randomness(vmbus_interrupt); |
| } |
| |
| static irqreturn_t vmbus_percpu_isr(int irq, void *dev_id) |
| { |
| vmbus_isr(); |
| return IRQ_HANDLED; |
| } |
| |
| /* |
| * 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) |
| { |
| struct kmsg_dump_iter iter; |
| size_t bytes_written; |
| |
| /* We are only interested in panics. */ |
| if ((reason != KMSG_DUMP_PANIC) || (!sysctl_record_panic_msg)) |
| return; |
| |
| /* |
| * Write dump contents to the page. No need to synchronize; panic should |
| * be single-threaded. |
| */ |
| kmsg_dump_rewind(&iter); |
| kmsg_dump_get_buffer(&iter, false, hv_panic_page, HV_HYP_PAGE_SIZE, |
| &bytes_written); |
| if (!bytes_written) |
| return; |
| /* |
| * P3 to contain the physical address of the panic page & P4 to |
| * contain the size of the panic data in that page. Rest of the |
| * registers are no-op when the NOTIFY_MSG flag is set. |
| */ |
| hv_set_register(HV_REGISTER_CRASH_P0, 0); |
| hv_set_register(HV_REGISTER_CRASH_P1, 0); |
| hv_set_register(HV_REGISTER_CRASH_P2, 0); |
| hv_set_register(HV_REGISTER_CRASH_P3, virt_to_phys(hv_panic_page)); |
| hv_set_register(HV_REGISTER_CRASH_P4, bytes_written); |
| |
| /* |
| * Let Hyper-V know there is crash data available along with |
| * the panic message. |
| */ |
| hv_set_register(HV_REGISTER_CRASH_CTL, |
| (HV_CRASH_CTL_CRASH_NOTIFY | HV_CRASH_CTL_CRASH_NOTIFY_MSG)); |
| } |
| |
| static struct kmsg_dumper hv_kmsg_dumper = { |
| .dump = hv_kmsg_dump, |
| }; |
| |
| static void hv_kmsg_dump_register(void) |
| { |
| int ret; |
| |
| hv_panic_page = hv_alloc_hyperv_zeroed_page(); |
| if (!hv_panic_page) { |
| pr_err("Hyper-V: panic message page memory allocation failed\n"); |
| return; |
| } |
| |
| ret = kmsg_dump_register(&hv_kmsg_dumper); |
| if (ret) { |
| pr_err("Hyper-V: kmsg dump register error 0x%x\n", ret); |
| hv_free_hyperv_page((unsigned long)hv_panic_page); |
| hv_panic_page = NULL; |
| } |
| } |
| |
| static struct ctl_table_header *hv_ctl_table_hdr; |
| |
| /* |
| * 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 = SYSCTL_ZERO, |
| .extra2 = SYSCTL_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; |
| |
| 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; |
| |
| /* |
| * VMbus interrupts are best modeled as per-cpu interrupts. If |
| * on an architecture with support for per-cpu IRQs (e.g. ARM64), |
| * allocate a per-cpu IRQ using standard Linux kernel functionality. |
| * If not on such an architecture (e.g., x86/x64), then rely on |
| * code in the arch-specific portion of the code tree to connect |
| * the VMbus interrupt handler. |
| */ |
| |
| if (vmbus_irq == -1) { |
| hv_setup_vmbus_handler(vmbus_isr); |
| } else { |
| vmbus_evt = alloc_percpu(long); |
| ret = request_percpu_irq(vmbus_irq, vmbus_percpu_isr, |
| "Hyper-V VMbus", vmbus_evt); |
| if (ret) { |
| pr_err("Can't request Hyper-V VMbus IRQ %d, Err %d", |
| vmbus_irq, ret); |
| free_percpu(vmbus_evt); |
| goto err_setup; |
| } |
| } |
| |
| ret = hv_synic_alloc(); |
| if (ret) |
| goto err_alloc; |
| |
| /* |
| * Initialize the per-cpu interrupt state and stimer state. |
| * Then 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_cpuhp; |
| hyperv_cpuhp_online = ret; |
| |
| ret = vmbus_connect(); |
| if (ret) |
| goto err_connect; |
| |
| if (hv_is_isolation_supported()) |
| sysctl_record_panic_msg = 0; |
| |
| /* |
| * Only register if the crash MSRs are available |
| */ |
| if (ms_hyperv.misc_features & HV_FEATURE_GUEST_CRASH_MSR_AVAILABLE) { |
| u64 hyperv_crash_ctl; |
| /* |
| * Panic message recording (sysctl_record_panic_msg) |
| * is enabled by default in non-isolated guests and |
| * disabled by default in isolated guests; the panic |
| * message recording won't be available in isolated |
| * guests should the following registration fail. |
| */ |
| 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. |
| */ |
| hyperv_crash_ctl = hv_get_register(HV_REGISTER_CRASH_CTL); |
| if (hyperv_crash_ctl & HV_CRASH_CTL_CRASH_NOTIFY_MSG) |
| hv_kmsg_dump_register(); |
| |
| register_die_notifier(&hyperv_die_block); |
| } |
| |
| /* |
| * Always register the panic notifier because we need to unload |
| * the VMbus channel connection to prevent any VMbus |
| * activity after the VM panics. |
| */ |
| atomic_notifier_chain_register(&panic_notifier_list, |
| &hyperv_panic_block); |
| |
| vmbus_request_offers(); |
| |
| return 0; |
| |
| err_connect: |
| cpuhp_remove_state(hyperv_cpuhp_online); |
| err_cpuhp: |
| hv_synic_free(); |
| err_alloc: |
| if (vmbus_irq == -1) { |
| hv_remove_vmbus_handler(); |
| } else { |
| free_percpu_irq(vmbus_irq, vmbus_evt); |
| free_percpu(vmbus_evt); |
| } |
| err_setup: |
| bus_unregister(&hv_bus); |
| 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)(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); |
| struct vmbus_channel *chan |
| = container_of(kobj, struct vmbus_channel, kobj); |
| |
| if (!attribute->show) |
| return -EIO; |
| |
| return attribute->show(chan, buf); |
| } |
| |
| static ssize_t vmbus_chan_attr_store(struct kobject *kobj, |
| struct attribute *attr, const char *buf, |
| size_t count) |
| { |
| const struct vmbus_chan_attribute *attribute |
| = container_of(attr, struct vmbus_chan_attribute, attr); |
| struct vmbus_channel *chan |
| = container_of(kobj, struct vmbus_channel, kobj); |
| |
| if (!attribute->store) |
| return -EIO; |
| |
| return attribute->store(chan, buf, count); |
| } |
| |
| static const struct sysfs_ops vmbus_chan_sysfs_ops = { |
| .show = vmbus_chan_attr_show, |
| .store = vmbus_chan_attr_store, |
| }; |
| |
| static ssize_t out_mask_show(struct vmbus_channel *channel, char *buf) |
| { |
| struct hv_ring_buffer_info *rbi = &channel->outbound; |
| ssize_t ret; |
| |
| mutex_lock(&rbi->ring_buffer_mutex); |
| if (!rbi->ring_buffer) { |
| mutex_unlock(&rbi->ring_buffer_mutex); |
| return -EINVAL; |
| } |
| |
| ret = sprintf(buf, "%u\n", rbi->ring_buffer->interrupt_mask); |
| mutex_unlock(&rbi->ring_buffer_mutex); |
| return ret; |
| } |
| static VMBUS_CHAN_ATTR_RO(out_mask); |
| |
| static ssize_t in_mask_show(struct vmbus_channel *channel, char *buf) |
| { |
| struct hv_ring_buffer_info *rbi = &channel->inbound; |
| ssize_t ret; |
| |
| mutex_lock(&rbi->ring_buffer_mutex); |
| if (!rbi->ring_buffer) { |
| mutex_unlock(&rbi->ring_buffer_mutex); |
| return -EINVAL; |
| } |
| |
| ret = sprintf(buf, "%u\n", rbi->ring_buffer->interrupt_mask); |
| mutex_unlock(&rbi->ring_buffer_mutex); |
| return ret; |
| } |
| static VMBUS_CHAN_ATTR_RO(in_mask); |
| |
| static ssize_t read_avail_show(struct vmbus_channel *channel, char *buf) |
| { |
| struct hv_ring_buffer_info *rbi = &channel->inbound; |
| ssize_t ret; |
| |
| mutex_lock(&rbi->ring_buffer_mutex); |
| if (!rbi->ring_buffer) { |
| mutex_unlock(&rbi->ring_buffer_mutex); |
| return -EINVAL; |
| } |
| |
| ret = sprintf(buf, "%u\n", hv_get_bytes_to_read(rbi)); |
| mutex_unlock(&rbi->ring_buffer_mutex); |
| return ret; |
| } |
| static VMBUS_CHAN_ATTR_RO(read_avail); |
| |
| static ssize_t write_avail_show(struct vmbus_channel *channel, char *buf) |
| { |
| struct hv_ring_buffer_info *rbi = &channel->outbound; |
| ssize_t ret; |
| |
| mutex_lock(&rbi->ring_buffer_mutex); |
| if (!rbi->ring_buffer) { |
| mutex_unlock(&rbi->ring_buffer_mutex); |
| return -EINVAL; |
| } |
| |
| ret = sprintf(buf, "%u\n", hv_get_bytes_to_write(rbi)); |
| mutex_unlock(&rbi->ring_buffer_mutex); |
| return ret; |
| } |
| static VMBUS_CHAN_ATTR_RO(write_avail); |
| |
| static ssize_t target_cpu_show(struct vmbus_channel *channel, char *buf) |
| { |
| return sprintf(buf, "%u\n", channel->target_cpu); |
| } |
| static ssize_t target_cpu_store(struct vmbus_channel *channel, |
| const char *buf, size_t count) |
| { |
| u32 target_cpu, origin_cpu; |
| ssize_t ret = count; |
| |
| if (vmbus_proto_version < VERSION_WIN10_V4_1) |
| return -EIO; |
| |
| if (sscanf(buf, "%uu", &target_cpu) != 1) |
| return -EIO; |
| |
| /* Validate target_cpu for the cpumask_test_cpu() operation below. */ |
| if (target_cpu >= nr_cpumask_bits) |
| return -EINVAL; |
| |
| /* No CPUs should come up or down during this. */ |
| cpus_read_lock(); |
| |
| if (!cpu_online(target_cpu)) { |
| cpus_read_unlock(); |
| return -EINVAL; |
| } |
| |
| /* |
| * Synchronizes target_cpu_store() and channel closure: |
| * |
| * { Initially: state = CHANNEL_OPENED } |
| * |
| * CPU1 CPU2 |
| * |
| * [target_cpu_store()] [vmbus_disconnect_ring()] |
| * |
| * LOCK channel_mutex LOCK channel_mutex |
| * LOAD r1 = state LOAD r2 = state |
| * IF (r1 == CHANNEL_OPENED) IF (r2 == CHANNEL_OPENED) |
| * SEND MODIFYCHANNEL STORE state = CHANNEL_OPEN |
| * [...] SEND CLOSECHANNEL |
| * UNLOCK channel_mutex UNLOCK channel_mutex |
| * |
| * Forbids: r1 == r2 == CHANNEL_OPENED (i.e., CPU1's LOCK precedes |
| * CPU2's LOCK) && CPU2's SEND precedes CPU1's SEND |
| * |
| * Note. The host processes the channel messages "sequentially", in |
| * the order in which they are received on a per-partition basis. |
| */ |
| mutex_lock(&vmbus_connection.channel_mutex); |
| |
| /* |
| * Hyper-V will ignore MODIFYCHANNEL messages for "non-open" channels; |
| * avoid sending the message and fail here for such channels. |
| */ |
| if (channel->state != CHANNEL_OPENED_STATE) { |
| ret = -EIO; |
| goto cpu_store_unlock; |
| } |
| |
| origin_cpu = channel->target_cpu; |
| if (target_cpu == origin_cpu) |
| goto cpu_store_unlock; |
| |
| if (vmbus_send_modifychannel(channel, |
| hv_cpu_number_to_vp_number(target_cpu))) { |
| ret = -EIO; |
| goto cpu_store_unlock; |
| } |
| |
| /* |
| * For version before VERSION_WIN10_V5_3, the following warning holds: |
| * |
| * Warning. At this point, there is *no* guarantee that the host will |
| * have successfully processed the vmbus_send_modifychannel() request. |
| * See the header comment of vmbus_send_modifychannel() for more info. |
| * |
| * Lags in the processing of the above vmbus_send_modifychannel() can |
| * result in missed interrupts if the "old" target CPU is taken offline |
| * before Hyper-V starts sending interrupts to the "new" target CPU. |
| * But apart from this offlining scenario, the code tolerates such |
| * lags. It will function correctly even if a channel interrupt comes |
| * in on a CPU that is different from the channel target_cpu value. |
| */ |
| |
| channel->target_cpu = target_cpu; |
| |
| /* See init_vp_index(). */ |
| if (hv_is_perf_channel(channel)) |
| hv_update_allocated_cpus(origin_cpu, target_cpu); |
| |
| /* Currently set only for storvsc channels. */ |
| if (channel->change_target_cpu_callback) { |
| (*channel->change_target_cpu_callback)(channel, |
| origin_cpu, target_cpu); |
| } |
| |
| cpu_store_unlock: |
| mutex_unlock(&vmbus_connection.channel_mutex); |
| cpus_read_unlock(); |
| return ret; |
| } |
| static VMBUS_CHAN_ATTR(cpu, 0644, target_cpu_show, target_cpu_store); |
| |
| static ssize_t channel_pending_show(struct vmbus_channel *channel, |
| char *buf) |
| { |
| return sprintf(buf, "%d\n", |
| channel_pending(channel, |
| vmbus_connection.monitor_pages[1])); |
| } |
| static VMBUS_CHAN_ATTR(pending, 0444, channel_pending_show, NULL); |
| |
| static ssize_t channel_latency_show(struct vmbus_channel *channel, |
| char *buf) |
| { |
| return sprintf(buf, "%d\n", |
| channel_latency(channel, |
| vmbus_connection.monitor_pages[1])); |
| } |
| static VMBUS_CHAN_ATTR(latency, 0444, channel_latency_show, NULL); |
| |
| static ssize_t channel_interrupts_show(struct vmbus_channel *channel, char *buf) |
| { |
| return sprintf(buf, "%llu\n", channel->interrupts); |
| } |
| static VMBUS_CHAN_ATTR(interrupts, 0444, channel_interrupts_show, NULL); |
| |
| static ssize_t channel_events_show(struct vmbus_channel *channel, char *buf) |
| { |
| return sprintf(buf, "%llu\n", channel->sig_events); |
| } |
| static VMBUS_CHAN_ATTR(events, 0444, channel_events_show, NULL); |
| |
| static ssize_t channel_intr_in_full_show(struct vmbus_channel *channel, |
| char *buf) |
| { |
| return sprintf(buf, "%llu\n", |
| (unsigned long long)channel->intr_in_full); |
| } |
| static VMBUS_CHAN_ATTR(intr_in_full, 0444, channel_intr_in_full_show, NULL); |
| |
| static ssize_t channel_intr_out_empty_show(struct vmbus_channel *channel, |
| char *buf) |
| { |
| return sprintf(buf, "%llu\n", |
| (unsigned long long)channel->intr_out_empty); |
| } |
| static VMBUS_CHAN_ATTR(intr_out_empty, 0444, channel_intr_out_empty_show, NULL); |
| |
| static ssize_t channel_out_full_first_show(struct vmbus_channel *channel, |
| char *buf) |
| { |
| return sprintf(buf, "%llu\n", |
| (unsigned long long)channel->out_full_first); |
| } |
| static VMBUS_CHAN_ATTR(out_full_first, 0444, channel_out_full_first_show, NULL); |
| |
| static ssize_t channel_out_full_total_show(struct vmbus_channel *channel, |
| char *buf) |
| { |
| return sprintf(buf, "%llu\n", |
| (unsigned long long)channel->out_full_total); |
| } |
| static VMBUS_CHAN_ATTR(out_full_total, 0444, channel_out_full_total_show, NULL); |
| |
| static ssize_t subchannel_monitor_id_show(struct vmbus_channel *channel, |
| char *buf) |
| { |
| return sprintf(buf, "%u\n", channel->offermsg.monitorid); |
| } |
| static VMBUS_CHAN_ATTR(monitor_id, 0444, subchannel_monitor_id_show, NULL); |
| |
| static ssize_t subchannel_id_show(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_intr_in_full.attr, |
| &chan_attr_intr_out_empty.attr, |
| &chan_attr_out_full_first.attr, |
| &chan_attr_out_full_total.attr, |
| &chan_attr_monitor_id.attr, |
| &chan_attr_subchannel_id.attr, |
| NULL |
| }; |
| |
| /* |
| * Channel-level attribute_group callback function. Returns the permission for |
| * each attribute, and returns 0 if an attribute is not visible. |
| */ |
| static umode_t vmbus_chan_attr_is_visible(struct kobject *kobj, |
| struct attribute *attr, int idx) |
| { |
| const struct vmbus_channel *channel = |
| container_of(kobj, struct vmbus_channel, kobj); |
| |
| /* Hide the monitor attributes if the monitor mechanism is not used. */ |
| if (!channel->offermsg.monitor_allocated && |
| (attr == &chan_attr_pending.attr || |
| attr == &chan_attr_latency.attr || |
| attr == &chan_attr_monitor_id.attr)) |
| return 0; |
| |
| return attr->mode; |
| } |
| |
| static struct attribute_group vmbus_chan_group = { |
| .attrs = vmbus_chan_attrs, |
| .is_visible = vmbus_chan_attr_is_visible |
| }; |
| |
| static struct kobj_type vmbus_chan_ktype = { |
| .sysfs_ops = &vmbus_chan_sysfs_ops, |
| .release = vmbus_chan_release, |
| }; |
| |
| /* |
| * vmbus_add_channel_kobj - setup a sub-directory under device/channels |
| */ |
| int vmbus_add_channel_kobj(struct hv_device *dev, struct vmbus_channel *channel) |
| { |
| const struct device *device = &dev->device; |
| 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) { |
| kobject_put(kobj); |
| return ret; |
| } |
| |
| ret = sysfs_create_group(kobj, &vmbus_chan_group); |
| |
| if (ret) { |
| /* |
| * The calling functions' error handling paths will cleanup the |
| * empty channel directory. |
| */ |
| kobject_put(kobj); |
| dev_err(device, "Unable to set up channel sysfs files\n"); |
| return ret; |
| } |
| |
| kobject_uevent(kobj, KOBJ_ADD); |
| |
| return 0; |
| } |
| |
| /* |
| * vmbus_remove_channel_attr_group - remove the channel's attribute group |
| */ |
| void vmbus_remove_channel_attr_group(struct vmbus_channel *channel) |
| { |
| sysfs_remove_group(&channel->kobj, &vmbus_chan_group); |
| } |
| |
| /* |
| * vmbus_device_create - Creates and registers a new child device |
| * on the vmbus. |
| */ |
| struct hv_device *vmbus_device_create(const guid_t *type, |
| const guid_t *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; |
| guid_copy(&child_device_obj->dev_type, type); |
| guid_copy(&child_device_obj->dev_instance, instance); |
| 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); |
| |
| child_device_obj->device.bus = &hv_bus; |
| child_device_obj->device.parent = &hv_acpi_dev->dev; |
| child_device_obj->device.release = vmbus_device_release; |
| |
| child_device_obj->device.dma_parms = &child_device_obj->dma_parms; |
| child_device_obj->device.dma_mask = &child_device_obj->dma_mask; |
| dma_set_mask(&child_device_obj->device, DMA_BIT_MASK(64)); |
| |
| /* |
| * 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; |
| } |
| hv_debug_add_dev_dir(child_device_obj); |
| |
| 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; |
| struct resource r; |
| |
| 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; |
| |
| /* |
| * The IRQ information is needed only on ARM64, which Hyper-V |
| * sets up in the extended format. IRQ information is present |
| * on x86/x64 in the non-extended format but it is not used by |
| * Linux. So don't bother checking for the non-extended format. |
| */ |
| case ACPI_RESOURCE_TYPE_EXTENDED_IRQ: |
| if (!acpi_dev_resource_interrupt(res, 0, &r)) { |
| pr_err("Unable to parse Hyper-V ACPI interrupt\n"); |
| return AE_ERROR; |
| } |
| /* ARM64 INTID for VMbus */ |
| vmbus_interrupt = res->data.extended_irq.interrupts[0]; |
| /* Linux IRQ number */ |
| vmbus_irq = r.start; |
| return AE_OK; |
| |
| 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; |
| mutex_lock(&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: |
| mutex_unlock(&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; |
| |
| mutex_lock(&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); |
| mutex_unlock(&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; |
| |
| /* |
| * Older versions of Hyper-V for ARM64 fail to include the _CCA |
| * method on the top level VMbus device in the DSDT. But devices |
| * are hardware coherent in all current Hyper-V use cases, so fix |
| * up the ACPI device to behave as if _CCA is present and indicates |
| * hardware coherence. |
| */ |
| ACPI_COMPANION_SET(&device->dev, device); |
| if (IS_ENABLED(CONFIG_ACPI_CCA_REQUIRED) && |
| device_get_dma_attr(&device->dev) == DEV_DMA_NOT_SUPPORTED) { |
| pr_info("No ACPI _CCA found; assuming coherent device I/O\n"); |
| device->flags.cca_seen = true; |
| device->flags.coherent_dma = true; |
| } |
| |
| 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; |
| } |
| |
| #ifdef CONFIG_PM_SLEEP |
| static int vmbus_bus_suspend(struct device *dev) |
| { |
| struct vmbus_channel *channel, *sc; |
| |
| while (atomic_read(&vmbus_connection.offer_in_progress) != 0) { |
| /* |
| * We wait here until the completion of any channel |
| * offers that are currently in progress. |
| */ |
| usleep_range(1000, 2000); |
| } |
| |
| mutex_lock(&vmbus_connection.channel_mutex); |
| list_for_each_entry(channel, &vmbus_connection.chn_list, listentry) { |
| if (!is_hvsock_channel(channel)) |
| continue; |
| |
| vmbus_force_channel_rescinded(channel); |
| } |
| mutex_unlock(&vmbus_connection.channel_mutex); |
| |
| /* |
| * Wait until all the sub-channels and hv_sock channels have been |
| * cleaned up. Sub-channels should be destroyed upon suspend, otherwise |
| * they would conflict with the new sub-channels that will be created |
| * in the resume path. hv_sock channels should also be destroyed, but |
| * a hv_sock channel of an established hv_sock connection can not be |
| * really destroyed since it may still be referenced by the userspace |
| * application, so we just force the hv_sock channel to be rescinded |
| * by vmbus_force_channel_rescinded(), and the userspace application |
| * will thoroughly destroy the channel after hibernation. |
| * |
| * Note: the counter nr_chan_close_on_suspend may never go above 0 if |
| * the VM has no sub-channel and hv_sock channel, e.g. a 1-vCPU VM. |
| */ |
| if (atomic_read(&vmbus_connection.nr_chan_close_on_suspend) > 0) |
| wait_for_completion(&vmbus_connection.ready_for_suspend_event); |
| |
| if (atomic_read(&vmbus_connection.nr_chan_fixup_on_resume) != 0) { |
| pr_err("Can not suspend due to a previous failed resuming\n"); |
| return -EBUSY; |
| } |
| |
| mutex_lock(&vmbus_connection.channel_mutex); |
| |
| list_for_each_entry(channel, &vmbus_connection.chn_list, listentry) { |
| /* |
| * Remove the channel from the array of channels and invalidate |
| * the channel's relid. Upon resume, vmbus_onoffer() will fix |
| * up the relid (and other fields, if necessary) and add the |
| * channel back to the array. |
| */ |
| vmbus_channel_unmap_relid(channel); |
| channel->offermsg.child_relid = INVALID_RELID; |
| |
| if (is_hvsock_channel(channel)) { |
| if (!channel->rescind) { |
| pr_err("hv_sock channel not rescinded!\n"); |
| WARN_ON_ONCE(1); |
| } |
| continue; |
| } |
| |
| list_for_each_entry(sc, &channel->sc_list, sc_list) { |
| pr_err("Sub-channel not deleted!\n"); |
| WARN_ON_ONCE(1); |
| } |
| |
| atomic_inc(&vmbus_connection.nr_chan_fixup_on_resume); |
| } |
| |
| mutex_unlock(&vmbus_connection.channel_mutex); |
| |
| vmbus_initiate_unload(false); |
| |
| /* Reset the event for the next resume. */ |
| reinit_completion(&vmbus_connection.ready_for_resume_event); |
| |
| return 0; |
| } |
| |
| static int vmbus_bus_resume(struct device *dev) |
| { |
| struct vmbus_channel_msginfo *msginfo; |
| size_t msgsize; |
| int ret; |
| |
| /* |
| * We only use the 'vmbus_proto_version', which was in use before |
| * hibernation, to re-negotiate with the host. |
| */ |
| if (!vmbus_proto_version) { |
| pr_err("Invalid proto version = 0x%x\n", vmbus_proto_version); |
| return -EINVAL; |
| } |
| |
| msgsize = sizeof(*msginfo) + |
| sizeof(struct vmbus_channel_initiate_contact); |
| |
| msginfo = kzalloc(msgsize, GFP_KERNEL); |
| |
| if (msginfo == NULL) |
| return -ENOMEM; |
| |
| ret = vmbus_negotiate_version(msginfo, vmbus_proto_version); |
| |
| kfree(msginfo); |
| |
| if (ret != 0) |
| return ret; |
| |
| WARN_ON(atomic_read(&vmbus_connection.nr_chan_fixup_on_resume) == 0); |
| |
| vmbus_request_offers(); |
| |
| if (wait_for_completion_timeout( |
| &vmbus_connection.ready_for_resume_event, 10 * HZ) == 0) |
| pr_err("Some vmbus device is missing after suspending?\n"); |
| |
| /* Reset the event for the next suspend. */ |
| reinit_completion(&vmbus_connection.ready_for_suspend_event); |
| |
| return 0; |
| } |
| #else |
| #define vmbus_bus_suspend NULL |
| #define vmbus_bus_resume NULL |
| #endif /* CONFIG_PM_SLEEP */ |
| |
| static const struct acpi_device_id vmbus_acpi_device_ids[] = { |
| {"VMBUS", 0}, |
| {"VMBus", 0}, |
| {"", 0}, |
| }; |
| MODULE_DEVICE_TABLE(acpi, vmbus_acpi_device_ids); |
| |
| /* |
| * Note: we must use the "no_irq" ops, otherwise hibernation can not work with |
| * PCI device assignment, because "pci_dev_pm_ops" uses the "noirq" ops: in |
| * the resume path, the pci "noirq" restore op runs before "non-noirq" op (see |
| * resume_target_kernel() -> dpm_resume_start(), and hibernation_restore() -> |
| * dpm_resume_end()). This means vmbus_bus_resume() and the pci-hyperv's |
| * resume callback must also run via the "noirq" ops. |
| * |
| * Set suspend_noirq/resume_noirq to NULL for Suspend-to-Idle: see the comment |
| * earlier in this file before vmbus_pm. |
| */ |
| |
| static const struct dev_pm_ops vmbus_bus_pm = { |
| .suspend_noirq = NULL, |
| .resume_noirq = NULL, |
| .freeze_noirq = vmbus_bus_suspend, |
| .thaw_noirq = vmbus_bus_resume, |
| .poweroff_noirq = vmbus_bus_suspend, |
| .restore_noirq = vmbus_bus_resume |
| }; |
| |
| static struct acpi_driver vmbus_acpi_driver = { |
| .name = "vmbus", |
| .ids = vmbus_acpi_device_ids, |
| .ops = { |
| .add = vmbus_acpi_add, |
| .remove = vmbus_acpi_remove, |
| }, |
| .drv.pm = &vmbus_bus_pm, |
| }; |
| |
| static void hv_kexec_handler(void) |
| { |
| hv_stimer_global_cleanup(); |
| vmbus_initiate_unload(false); |
| /* Make sure conn_state is set as hv_synic_cleanup checks for it */ |
| mb(); |
| cpuhp_remove_state(hyperv_cpuhp_online); |
| }; |
| |
| static void hv_crash_handler(struct pt_regs *regs) |
| { |
| int cpu; |
| |
| 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. |
| */ |
| cpu = smp_processor_id(); |
| hv_stimer_cleanup(cpu); |
| hv_synic_disable_regs(cpu); |
| }; |
| |
| static int hv_synic_suspend(void) |
| { |
| /* |
| * When we reach here, all the non-boot CPUs have been offlined. |
| * If we're in a legacy configuration where stimer Direct Mode is |
| * not enabled, the stimers on the non-boot CPUs have been unbound |
| * in hv_synic_cleanup() -> hv_stimer_legacy_cleanup() -> |
| * hv_stimer_cleanup() -> clockevents_unbind_device(). |
| * |
| * hv_synic_suspend() only runs on CPU0 with interrupts disabled. |
| * Here we do not call hv_stimer_legacy_cleanup() on CPU0 because: |
| * 1) it's unnecessary as interrupts remain disabled between |
| * syscore_suspend() and syscore_resume(): see create_image() and |
| * resume_target_kernel() |
| * 2) the stimer on CPU0 is automatically disabled later by |
| * syscore_suspend() -> timekeeping_suspend() -> tick_suspend() -> ... |
| * -> clockevents_shutdown() -> ... -> hv_ce_shutdown() |
| * 3) a warning would be triggered if we call |
| * clockevents_unbind_device(), which may sleep, in an |
| * interrupts-disabled context. |
| */ |
| |
| hv_synic_disable_regs(0); |
| |
| return 0; |
| } |
| |
| static void hv_synic_resume(void) |
| { |
| hv_synic_enable_regs(0); |
| |
| /* |
| * Note: we don't need to call hv_stimer_init(0), because the timer |
| * on CPU0 is not unbound in hv_synic_suspend(), and the timer is |
| * automatically re-enabled in timekeeping_resume(). |
| */ |
| } |
| |
| /* The callbacks run only on CPU0, with irqs_disabled. */ |
| static struct syscore_ops hv_synic_syscore_ops = { |
| .suspend = hv_synic_suspend, |
| .resume = hv_synic_resume, |
| }; |
| |
| static int __init hv_acpi_init(void) |
| { |
| int ret, t; |
| |
| if (!hv_is_hyperv_initialized()) |
| return -ENODEV; |
| |
| if (hv_root_partition) |
| return 0; |
| |
| 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; |
| } |
| |
| /* |
| * If we're on an architecture with a hardcoded hypervisor |
| * vector (i.e. x86/x64), override the VMbus interrupt found |
| * in the ACPI tables. Ensure vmbus_irq is not set since the |
| * normal Linux IRQ mechanism is not used in this case. |
| */ |
| #ifdef HYPERVISOR_CALLBACK_VECTOR |
| vmbus_interrupt = HYPERVISOR_CALLBACK_VECTOR; |
| vmbus_irq = -1; |
| #endif |
| |
| hv_debug_init(); |
| |
| ret = vmbus_bus_init(); |
| if (ret) |
| goto cleanup; |
| |
| hv_setup_kexec_handler(hv_kexec_handler); |
| hv_setup_crash_handler(hv_crash_handler); |
| |
| register_syscore_ops(&hv_synic_syscore_ops); |
| |
| return 0; |
| |
| cleanup: |
| acpi_bus_unregister_driver(&vmbus_acpi_driver); |
| hv_acpi_dev = NULL; |
| return ret; |
| } |
| |
| static void __exit vmbus_exit(void) |
| { |
| int cpu; |
| |
| unregister_syscore_ops(&hv_synic_syscore_ops); |
| |
| hv_remove_kexec_handler(); |
| hv_remove_crash_handler(); |
| vmbus_connection.conn_state = DISCONNECTED; |
| hv_stimer_global_cleanup(); |
| vmbus_disconnect(); |
| if (vmbus_irq == -1) { |
| hv_remove_vmbus_handler(); |
| } else { |
| free_percpu_irq(vmbus_irq, vmbus_evt); |
| free_percpu(vmbus_evt); |
| } |
| 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); |
| } |
| hv_debug_rm_all_dir(); |
| |
| vmbus_free_channels(); |
| kfree(vmbus_connection.channels); |
| |
| if (ms_hyperv.misc_features & HV_FEATURE_GUEST_CRASH_MSR_AVAILABLE) { |
| kmsg_dump_unregister(&hv_kmsg_dumper); |
| unregister_die_notifier(&hyperv_die_block); |
| } |
| |
| /* |
| * The panic notifier is always registered, hence we should |
| * also unconditionally unregister it here as well. |
| */ |
| 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"); |
| MODULE_DESCRIPTION("Microsoft Hyper-V VMBus Driver"); |
| |
| subsys_initcall(hv_acpi_init); |
| module_exit(vmbus_exit); |