2 * Copyright (c) 2009, Microsoft Corporation.
4 * This program is free software; you can redistribute it and/or modify it
5 * under the terms and conditions of the GNU General Public License,
6 * version 2, as published by the Free Software Foundation.
8 * This program is distributed in the hope it will be useful, but WITHOUT
9 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
10 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
13 * You should have received a copy of the GNU General Public License along with
14 * this program; if not, write to the Free Software Foundation, Inc., 59 Temple
15 * Place - Suite 330, Boston, MA 02111-1307 USA.
18 * Haiyang Zhang <haiyangz@microsoft.com>
19 * Hank Janssen <hjanssen@microsoft.com>
20 * K. Y. Srinivasan <kys@microsoft.com>
23 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
25 #include <linux/init.h>
26 #include <linux/module.h>
27 #include <linux/device.h>
28 #include <linux/interrupt.h>
29 #include <linux/sysctl.h>
30 #include <linux/slab.h>
31 #include <linux/acpi.h>
32 #include <linux/completion.h>
33 #include <linux/hyperv.h>
34 #include <linux/kernel_stat.h>
35 #include <linux/clockchips.h>
36 #include <linux/cpu.h>
37 #include <linux/sched/task_stack.h>
39 #include <asm/mshyperv.h>
40 #include <linux/notifier.h>
41 #include <linux/ptrace.h>
42 #include <linux/screen_info.h>
43 #include <linux/kdebug.h>
44 #include <linux/efi.h>
45 #include <linux/random.h>
46 #include "hyperv_vmbus.h"
49 struct list_head node;
50 struct hv_vmbus_device_id id;
53 static struct acpi_device *hv_acpi_dev;
55 static struct completion probe_event;
57 static int hyperv_cpuhp_online;
59 static void *hv_panic_page;
61 static int hyperv_panic_event(struct notifier_block *nb, unsigned long val,
66 regs = current_pt_regs();
68 hyperv_report_panic(regs, val);
72 static int hyperv_die_event(struct notifier_block *nb, unsigned long val,
75 struct die_args *die = (struct die_args *)args;
76 struct pt_regs *regs = die->regs;
78 hyperv_report_panic(regs, val);
82 static struct notifier_block hyperv_die_block = {
83 .notifier_call = hyperv_die_event,
85 static struct notifier_block hyperv_panic_block = {
86 .notifier_call = hyperv_panic_event,
89 static const char *fb_mmio_name = "fb_range";
90 static struct resource *fb_mmio;
91 static struct resource *hyperv_mmio;
92 static DEFINE_SEMAPHORE(hyperv_mmio_lock);
94 static int vmbus_exists(void)
96 if (hv_acpi_dev == NULL)
102 #define VMBUS_ALIAS_LEN ((sizeof((struct hv_vmbus_device_id *)0)->guid) * 2)
103 static void print_alias_name(struct hv_device *hv_dev, char *alias_name)
106 for (i = 0; i < VMBUS_ALIAS_LEN; i += 2)
107 sprintf(&alias_name[i], "%02x", hv_dev->dev_type.b[i/2]);
110 static u8 channel_monitor_group(const struct vmbus_channel *channel)
112 return (u8)channel->offermsg.monitorid / 32;
115 static u8 channel_monitor_offset(const struct vmbus_channel *channel)
117 return (u8)channel->offermsg.monitorid % 32;
120 static u32 channel_pending(const struct vmbus_channel *channel,
121 const struct hv_monitor_page *monitor_page)
123 u8 monitor_group = channel_monitor_group(channel);
125 return monitor_page->trigger_group[monitor_group].pending;
128 static u32 channel_latency(const struct vmbus_channel *channel,
129 const struct hv_monitor_page *monitor_page)
131 u8 monitor_group = channel_monitor_group(channel);
132 u8 monitor_offset = channel_monitor_offset(channel);
134 return monitor_page->latency[monitor_group][monitor_offset];
137 static u32 channel_conn_id(struct vmbus_channel *channel,
138 struct hv_monitor_page *monitor_page)
140 u8 monitor_group = channel_monitor_group(channel);
141 u8 monitor_offset = channel_monitor_offset(channel);
142 return monitor_page->parameter[monitor_group][monitor_offset].connectionid.u.id;
145 static ssize_t id_show(struct device *dev, struct device_attribute *dev_attr,
148 struct hv_device *hv_dev = device_to_hv_device(dev);
150 if (!hv_dev->channel)
152 return sprintf(buf, "%d\n", hv_dev->channel->offermsg.child_relid);
154 static DEVICE_ATTR_RO(id);
156 static ssize_t state_show(struct device *dev, struct device_attribute *dev_attr,
159 struct hv_device *hv_dev = device_to_hv_device(dev);
161 if (!hv_dev->channel)
163 return sprintf(buf, "%d\n", hv_dev->channel->state);
165 static DEVICE_ATTR_RO(state);
167 static ssize_t monitor_id_show(struct device *dev,
168 struct device_attribute *dev_attr, char *buf)
170 struct hv_device *hv_dev = device_to_hv_device(dev);
172 if (!hv_dev->channel)
174 return sprintf(buf, "%d\n", hv_dev->channel->offermsg.monitorid);
176 static DEVICE_ATTR_RO(monitor_id);
178 static ssize_t class_id_show(struct device *dev,
179 struct device_attribute *dev_attr, char *buf)
181 struct hv_device *hv_dev = device_to_hv_device(dev);
183 if (!hv_dev->channel)
185 return sprintf(buf, "{%pUl}\n",
186 hv_dev->channel->offermsg.offer.if_type.b);
188 static DEVICE_ATTR_RO(class_id);
190 static ssize_t device_id_show(struct device *dev,
191 struct device_attribute *dev_attr, char *buf)
193 struct hv_device *hv_dev = device_to_hv_device(dev);
195 if (!hv_dev->channel)
197 return sprintf(buf, "{%pUl}\n",
198 hv_dev->channel->offermsg.offer.if_instance.b);
200 static DEVICE_ATTR_RO(device_id);
202 static ssize_t modalias_show(struct device *dev,
203 struct device_attribute *dev_attr, char *buf)
205 struct hv_device *hv_dev = device_to_hv_device(dev);
206 char alias_name[VMBUS_ALIAS_LEN + 1];
208 print_alias_name(hv_dev, alias_name);
209 return sprintf(buf, "vmbus:%s\n", alias_name);
211 static DEVICE_ATTR_RO(modalias);
214 static ssize_t numa_node_show(struct device *dev,
215 struct device_attribute *attr, char *buf)
217 struct hv_device *hv_dev = device_to_hv_device(dev);
219 if (!hv_dev->channel)
222 return sprintf(buf, "%d\n", hv_dev->channel->numa_node);
224 static DEVICE_ATTR_RO(numa_node);
227 static ssize_t server_monitor_pending_show(struct device *dev,
228 struct device_attribute *dev_attr,
231 struct hv_device *hv_dev = device_to_hv_device(dev);
233 if (!hv_dev->channel)
235 return sprintf(buf, "%d\n",
236 channel_pending(hv_dev->channel,
237 vmbus_connection.monitor_pages[1]));
239 static DEVICE_ATTR_RO(server_monitor_pending);
241 static ssize_t client_monitor_pending_show(struct device *dev,
242 struct device_attribute *dev_attr,
245 struct hv_device *hv_dev = device_to_hv_device(dev);
247 if (!hv_dev->channel)
249 return sprintf(buf, "%d\n",
250 channel_pending(hv_dev->channel,
251 vmbus_connection.monitor_pages[1]));
253 static DEVICE_ATTR_RO(client_monitor_pending);
255 static ssize_t server_monitor_latency_show(struct device *dev,
256 struct device_attribute *dev_attr,
259 struct hv_device *hv_dev = device_to_hv_device(dev);
261 if (!hv_dev->channel)
263 return sprintf(buf, "%d\n",
264 channel_latency(hv_dev->channel,
265 vmbus_connection.monitor_pages[0]));
267 static DEVICE_ATTR_RO(server_monitor_latency);
269 static ssize_t client_monitor_latency_show(struct device *dev,
270 struct device_attribute *dev_attr,
273 struct hv_device *hv_dev = device_to_hv_device(dev);
275 if (!hv_dev->channel)
277 return sprintf(buf, "%d\n",
278 channel_latency(hv_dev->channel,
279 vmbus_connection.monitor_pages[1]));
281 static DEVICE_ATTR_RO(client_monitor_latency);
283 static ssize_t server_monitor_conn_id_show(struct device *dev,
284 struct device_attribute *dev_attr,
287 struct hv_device *hv_dev = device_to_hv_device(dev);
289 if (!hv_dev->channel)
291 return sprintf(buf, "%d\n",
292 channel_conn_id(hv_dev->channel,
293 vmbus_connection.monitor_pages[0]));
295 static DEVICE_ATTR_RO(server_monitor_conn_id);
297 static ssize_t client_monitor_conn_id_show(struct device *dev,
298 struct device_attribute *dev_attr,
301 struct hv_device *hv_dev = device_to_hv_device(dev);
303 if (!hv_dev->channel)
305 return sprintf(buf, "%d\n",
306 channel_conn_id(hv_dev->channel,
307 vmbus_connection.monitor_pages[1]));
309 static DEVICE_ATTR_RO(client_monitor_conn_id);
311 static ssize_t out_intr_mask_show(struct device *dev,
312 struct device_attribute *dev_attr, char *buf)
314 struct hv_device *hv_dev = device_to_hv_device(dev);
315 struct hv_ring_buffer_debug_info outbound;
317 if (!hv_dev->channel)
319 if (hv_dev->channel->state != CHANNEL_OPENED_STATE)
321 hv_ringbuffer_get_debuginfo(&hv_dev->channel->outbound, &outbound);
322 return sprintf(buf, "%d\n", outbound.current_interrupt_mask);
324 static DEVICE_ATTR_RO(out_intr_mask);
326 static ssize_t out_read_index_show(struct device *dev,
327 struct device_attribute *dev_attr, char *buf)
329 struct hv_device *hv_dev = device_to_hv_device(dev);
330 struct hv_ring_buffer_debug_info outbound;
332 if (!hv_dev->channel)
334 if (hv_dev->channel->state != CHANNEL_OPENED_STATE)
336 hv_ringbuffer_get_debuginfo(&hv_dev->channel->outbound, &outbound);
337 return sprintf(buf, "%d\n", outbound.current_read_index);
339 static DEVICE_ATTR_RO(out_read_index);
341 static ssize_t out_write_index_show(struct device *dev,
342 struct device_attribute *dev_attr,
345 struct hv_device *hv_dev = device_to_hv_device(dev);
346 struct hv_ring_buffer_debug_info outbound;
348 if (!hv_dev->channel)
350 if (hv_dev->channel->state != CHANNEL_OPENED_STATE)
352 hv_ringbuffer_get_debuginfo(&hv_dev->channel->outbound, &outbound);
353 return sprintf(buf, "%d\n", outbound.current_write_index);
355 static DEVICE_ATTR_RO(out_write_index);
357 static ssize_t out_read_bytes_avail_show(struct device *dev,
358 struct device_attribute *dev_attr,
361 struct hv_device *hv_dev = device_to_hv_device(dev);
362 struct hv_ring_buffer_debug_info outbound;
364 if (!hv_dev->channel)
366 if (hv_dev->channel->state != CHANNEL_OPENED_STATE)
368 hv_ringbuffer_get_debuginfo(&hv_dev->channel->outbound, &outbound);
369 return sprintf(buf, "%d\n", outbound.bytes_avail_toread);
371 static DEVICE_ATTR_RO(out_read_bytes_avail);
373 static ssize_t out_write_bytes_avail_show(struct device *dev,
374 struct device_attribute *dev_attr,
377 struct hv_device *hv_dev = device_to_hv_device(dev);
378 struct hv_ring_buffer_debug_info outbound;
380 if (!hv_dev->channel)
382 if (hv_dev->channel->state != CHANNEL_OPENED_STATE)
384 hv_ringbuffer_get_debuginfo(&hv_dev->channel->outbound, &outbound);
385 return sprintf(buf, "%d\n", outbound.bytes_avail_towrite);
387 static DEVICE_ATTR_RO(out_write_bytes_avail);
389 static ssize_t in_intr_mask_show(struct device *dev,
390 struct device_attribute *dev_attr, char *buf)
392 struct hv_device *hv_dev = device_to_hv_device(dev);
393 struct hv_ring_buffer_debug_info inbound;
395 if (!hv_dev->channel)
397 if (hv_dev->channel->state != CHANNEL_OPENED_STATE)
399 hv_ringbuffer_get_debuginfo(&hv_dev->channel->inbound, &inbound);
400 return sprintf(buf, "%d\n", inbound.current_interrupt_mask);
402 static DEVICE_ATTR_RO(in_intr_mask);
404 static ssize_t in_read_index_show(struct device *dev,
405 struct device_attribute *dev_attr, char *buf)
407 struct hv_device *hv_dev = device_to_hv_device(dev);
408 struct hv_ring_buffer_debug_info inbound;
410 if (!hv_dev->channel)
412 if (hv_dev->channel->state != CHANNEL_OPENED_STATE)
414 hv_ringbuffer_get_debuginfo(&hv_dev->channel->inbound, &inbound);
415 return sprintf(buf, "%d\n", inbound.current_read_index);
417 static DEVICE_ATTR_RO(in_read_index);
419 static ssize_t in_write_index_show(struct device *dev,
420 struct device_attribute *dev_attr, char *buf)
422 struct hv_device *hv_dev = device_to_hv_device(dev);
423 struct hv_ring_buffer_debug_info inbound;
425 if (!hv_dev->channel)
427 if (hv_dev->channel->state != CHANNEL_OPENED_STATE)
429 hv_ringbuffer_get_debuginfo(&hv_dev->channel->inbound, &inbound);
430 return sprintf(buf, "%d\n", inbound.current_write_index);
432 static DEVICE_ATTR_RO(in_write_index);
434 static ssize_t in_read_bytes_avail_show(struct device *dev,
435 struct device_attribute *dev_attr,
438 struct hv_device *hv_dev = device_to_hv_device(dev);
439 struct hv_ring_buffer_debug_info inbound;
441 if (!hv_dev->channel)
443 if (hv_dev->channel->state != CHANNEL_OPENED_STATE)
445 hv_ringbuffer_get_debuginfo(&hv_dev->channel->inbound, &inbound);
446 return sprintf(buf, "%d\n", inbound.bytes_avail_toread);
448 static DEVICE_ATTR_RO(in_read_bytes_avail);
450 static ssize_t in_write_bytes_avail_show(struct device *dev,
451 struct device_attribute *dev_attr,
454 struct hv_device *hv_dev = device_to_hv_device(dev);
455 struct hv_ring_buffer_debug_info inbound;
457 if (!hv_dev->channel)
459 if (hv_dev->channel->state != CHANNEL_OPENED_STATE)
461 hv_ringbuffer_get_debuginfo(&hv_dev->channel->inbound, &inbound);
462 return sprintf(buf, "%d\n", inbound.bytes_avail_towrite);
464 static DEVICE_ATTR_RO(in_write_bytes_avail);
466 static ssize_t channel_vp_mapping_show(struct device *dev,
467 struct device_attribute *dev_attr,
470 struct hv_device *hv_dev = device_to_hv_device(dev);
471 struct vmbus_channel *channel = hv_dev->channel, *cur_sc;
473 int buf_size = PAGE_SIZE, n_written, tot_written;
474 struct list_head *cur;
479 tot_written = snprintf(buf, buf_size, "%u:%u\n",
480 channel->offermsg.child_relid, channel->target_cpu);
482 spin_lock_irqsave(&channel->lock, flags);
484 list_for_each(cur, &channel->sc_list) {
485 if (tot_written >= buf_size - 1)
488 cur_sc = list_entry(cur, struct vmbus_channel, sc_list);
489 n_written = scnprintf(buf + tot_written,
490 buf_size - tot_written,
492 cur_sc->offermsg.child_relid,
494 tot_written += n_written;
497 spin_unlock_irqrestore(&channel->lock, flags);
501 static DEVICE_ATTR_RO(channel_vp_mapping);
503 static ssize_t vendor_show(struct device *dev,
504 struct device_attribute *dev_attr,
507 struct hv_device *hv_dev = device_to_hv_device(dev);
508 return sprintf(buf, "0x%x\n", hv_dev->vendor_id);
510 static DEVICE_ATTR_RO(vendor);
512 static ssize_t device_show(struct device *dev,
513 struct device_attribute *dev_attr,
516 struct hv_device *hv_dev = device_to_hv_device(dev);
517 return sprintf(buf, "0x%x\n", hv_dev->device_id);
519 static DEVICE_ATTR_RO(device);
521 static ssize_t driver_override_store(struct device *dev,
522 struct device_attribute *attr,
523 const char *buf, size_t count)
525 struct hv_device *hv_dev = device_to_hv_device(dev);
526 char *driver_override, *old, *cp;
528 /* We need to keep extra room for a newline */
529 if (count >= (PAGE_SIZE - 1))
532 driver_override = kstrndup(buf, count, GFP_KERNEL);
533 if (!driver_override)
536 cp = strchr(driver_override, '\n');
541 old = hv_dev->driver_override;
542 if (strlen(driver_override)) {
543 hv_dev->driver_override = driver_override;
545 kfree(driver_override);
546 hv_dev->driver_override = NULL;
555 static ssize_t driver_override_show(struct device *dev,
556 struct device_attribute *attr, char *buf)
558 struct hv_device *hv_dev = device_to_hv_device(dev);
562 len = snprintf(buf, PAGE_SIZE, "%s\n", hv_dev->driver_override);
567 static DEVICE_ATTR_RW(driver_override);
569 /* Set up per device attributes in /sys/bus/vmbus/devices/<bus device> */
570 static struct attribute *vmbus_dev_attrs[] = {
572 &dev_attr_state.attr,
573 &dev_attr_monitor_id.attr,
574 &dev_attr_class_id.attr,
575 &dev_attr_device_id.attr,
576 &dev_attr_modalias.attr,
578 &dev_attr_numa_node.attr,
580 &dev_attr_server_monitor_pending.attr,
581 &dev_attr_client_monitor_pending.attr,
582 &dev_attr_server_monitor_latency.attr,
583 &dev_attr_client_monitor_latency.attr,
584 &dev_attr_server_monitor_conn_id.attr,
585 &dev_attr_client_monitor_conn_id.attr,
586 &dev_attr_out_intr_mask.attr,
587 &dev_attr_out_read_index.attr,
588 &dev_attr_out_write_index.attr,
589 &dev_attr_out_read_bytes_avail.attr,
590 &dev_attr_out_write_bytes_avail.attr,
591 &dev_attr_in_intr_mask.attr,
592 &dev_attr_in_read_index.attr,
593 &dev_attr_in_write_index.attr,
594 &dev_attr_in_read_bytes_avail.attr,
595 &dev_attr_in_write_bytes_avail.attr,
596 &dev_attr_channel_vp_mapping.attr,
597 &dev_attr_vendor.attr,
598 &dev_attr_device.attr,
599 &dev_attr_driver_override.attr,
602 ATTRIBUTE_GROUPS(vmbus_dev);
605 * vmbus_uevent - add uevent for our device
607 * This routine is invoked when a device is added or removed on the vmbus to
608 * generate a uevent to udev in the userspace. The udev will then look at its
609 * rule and the uevent generated here to load the appropriate driver
611 * The alias string will be of the form vmbus:guid where guid is the string
612 * representation of the device guid (each byte of the guid will be
613 * represented with two hex characters.
615 static int vmbus_uevent(struct device *device, struct kobj_uevent_env *env)
617 struct hv_device *dev = device_to_hv_device(device);
619 char alias_name[VMBUS_ALIAS_LEN + 1];
621 print_alias_name(dev, alias_name);
622 ret = add_uevent_var(env, "MODALIAS=vmbus:%s", alias_name);
626 static const uuid_le null_guid;
628 static inline bool is_null_guid(const uuid_le *guid)
630 if (uuid_le_cmp(*guid, null_guid))
635 static const struct hv_vmbus_device_id *
636 hv_vmbus_dev_match(const struct hv_vmbus_device_id *id, const uuid_le *guid)
640 return NULL; /* empty device table */
642 for (; !is_null_guid(&id->guid); id++)
643 if (!uuid_le_cmp(id->guid, *guid))
649 static const struct hv_vmbus_device_id *
650 hv_vmbus_dynid_match(struct hv_driver *drv, const uuid_le *guid)
652 const struct hv_vmbus_device_id *id = NULL;
653 struct vmbus_dynid *dynid;
655 spin_lock(&drv->dynids.lock);
656 list_for_each_entry(dynid, &drv->dynids.list, node) {
657 if (!uuid_le_cmp(dynid->id.guid, *guid)) {
662 spin_unlock(&drv->dynids.lock);
667 static const struct hv_vmbus_device_id vmbus_device_null = {
668 .guid = NULL_UUID_LE,
672 * Return a matching hv_vmbus_device_id pointer.
673 * If there is no match, return NULL.
675 static const struct hv_vmbus_device_id *hv_vmbus_get_id(struct hv_driver *drv,
676 struct hv_device *dev)
678 const uuid_le *guid = &dev->dev_type;
679 const struct hv_vmbus_device_id *id;
681 /* When driver_override is set, only bind to the matching driver */
682 if (dev->driver_override && strcmp(dev->driver_override, drv->name))
685 /* Look at the dynamic ids first, before the static ones */
686 id = hv_vmbus_dynid_match(drv, guid);
688 id = hv_vmbus_dev_match(drv->id_table, guid);
690 /* driver_override will always match, send a dummy id */
691 if (!id && dev->driver_override)
692 id = &vmbus_device_null;
697 /* vmbus_add_dynid - add a new device ID to this driver and re-probe devices */
698 static int vmbus_add_dynid(struct hv_driver *drv, uuid_le *guid)
700 struct vmbus_dynid *dynid;
702 dynid = kzalloc(sizeof(*dynid), GFP_KERNEL);
706 dynid->id.guid = *guid;
708 spin_lock(&drv->dynids.lock);
709 list_add_tail(&dynid->node, &drv->dynids.list);
710 spin_unlock(&drv->dynids.lock);
712 return driver_attach(&drv->driver);
715 static void vmbus_free_dynids(struct hv_driver *drv)
717 struct vmbus_dynid *dynid, *n;
719 spin_lock(&drv->dynids.lock);
720 list_for_each_entry_safe(dynid, n, &drv->dynids.list, node) {
721 list_del(&dynid->node);
724 spin_unlock(&drv->dynids.lock);
728 * store_new_id - sysfs frontend to vmbus_add_dynid()
730 * Allow GUIDs to be added to an existing driver via sysfs.
732 static ssize_t new_id_store(struct device_driver *driver, const char *buf,
735 struct hv_driver *drv = drv_to_hv_drv(driver);
739 retval = uuid_le_to_bin(buf, &guid);
743 if (hv_vmbus_dynid_match(drv, &guid))
746 retval = vmbus_add_dynid(drv, &guid);
751 static DRIVER_ATTR_WO(new_id);
754 * store_remove_id - remove a PCI device ID from this driver
756 * Removes a dynamic pci device ID to this driver.
758 static ssize_t remove_id_store(struct device_driver *driver, const char *buf,
761 struct hv_driver *drv = drv_to_hv_drv(driver);
762 struct vmbus_dynid *dynid, *n;
766 retval = uuid_le_to_bin(buf, &guid);
771 spin_lock(&drv->dynids.lock);
772 list_for_each_entry_safe(dynid, n, &drv->dynids.list, node) {
773 struct hv_vmbus_device_id *id = &dynid->id;
775 if (!uuid_le_cmp(id->guid, guid)) {
776 list_del(&dynid->node);
782 spin_unlock(&drv->dynids.lock);
786 static DRIVER_ATTR_WO(remove_id);
788 static struct attribute *vmbus_drv_attrs[] = {
789 &driver_attr_new_id.attr,
790 &driver_attr_remove_id.attr,
793 ATTRIBUTE_GROUPS(vmbus_drv);
797 * vmbus_match - Attempt to match the specified device to the specified driver
799 static int vmbus_match(struct device *device, struct device_driver *driver)
801 struct hv_driver *drv = drv_to_hv_drv(driver);
802 struct hv_device *hv_dev = device_to_hv_device(device);
804 /* The hv_sock driver handles all hv_sock offers. */
805 if (is_hvsock_channel(hv_dev->channel))
808 if (hv_vmbus_get_id(drv, hv_dev))
815 * vmbus_probe - Add the new vmbus's child device
817 static int vmbus_probe(struct device *child_device)
820 struct hv_driver *drv =
821 drv_to_hv_drv(child_device->driver);
822 struct hv_device *dev = device_to_hv_device(child_device);
823 const struct hv_vmbus_device_id *dev_id;
825 dev_id = hv_vmbus_get_id(drv, dev);
827 ret = drv->probe(dev, dev_id);
829 pr_err("probe failed for device %s (%d)\n",
830 dev_name(child_device), ret);
833 pr_err("probe not set for driver %s\n",
834 dev_name(child_device));
841 * vmbus_remove - Remove a vmbus device
843 static int vmbus_remove(struct device *child_device)
845 struct hv_driver *drv;
846 struct hv_device *dev = device_to_hv_device(child_device);
848 if (child_device->driver) {
849 drv = drv_to_hv_drv(child_device->driver);
859 * vmbus_shutdown - Shutdown a vmbus device
861 static void vmbus_shutdown(struct device *child_device)
863 struct hv_driver *drv;
864 struct hv_device *dev = device_to_hv_device(child_device);
867 /* The device may not be attached yet */
868 if (!child_device->driver)
871 drv = drv_to_hv_drv(child_device->driver);
879 * vmbus_device_release - Final callback release of the vmbus child device
881 static void vmbus_device_release(struct device *device)
883 struct hv_device *hv_dev = device_to_hv_device(device);
884 struct vmbus_channel *channel = hv_dev->channel;
886 mutex_lock(&vmbus_connection.channel_mutex);
887 hv_process_channel_removal(channel);
888 mutex_unlock(&vmbus_connection.channel_mutex);
892 /* The one and only one */
893 static struct bus_type hv_bus = {
895 .match = vmbus_match,
896 .shutdown = vmbus_shutdown,
897 .remove = vmbus_remove,
898 .probe = vmbus_probe,
899 .uevent = vmbus_uevent,
900 .dev_groups = vmbus_dev_groups,
901 .drv_groups = vmbus_drv_groups,
904 struct onmessage_work_context {
905 struct work_struct work;
906 struct hv_message msg;
909 static void vmbus_onmessage_work(struct work_struct *work)
911 struct onmessage_work_context *ctx;
913 /* Do not process messages if we're in DISCONNECTED state */
914 if (vmbus_connection.conn_state == DISCONNECTED)
917 ctx = container_of(work, struct onmessage_work_context,
919 vmbus_onmessage(&ctx->msg);
923 static void hv_process_timer_expiration(struct hv_message *msg,
924 struct hv_per_cpu_context *hv_cpu)
926 struct clock_event_device *dev = hv_cpu->clk_evt;
928 if (dev->event_handler)
929 dev->event_handler(dev);
931 vmbus_signal_eom(msg, HVMSG_TIMER_EXPIRED);
934 void vmbus_on_msg_dpc(unsigned long data)
936 struct hv_per_cpu_context *hv_cpu = (void *)data;
937 void *page_addr = hv_cpu->synic_message_page;
938 struct hv_message *msg = (struct hv_message *)page_addr +
940 struct vmbus_channel_message_header *hdr;
941 const struct vmbus_channel_message_table_entry *entry;
942 struct onmessage_work_context *ctx;
943 u32 message_type = msg->header.message_type;
945 if (message_type == HVMSG_NONE)
949 hdr = (struct vmbus_channel_message_header *)msg->u.payload;
951 trace_vmbus_on_msg_dpc(hdr);
953 if (hdr->msgtype >= CHANNELMSG_COUNT) {
954 WARN_ONCE(1, "unknown msgtype=%d\n", hdr->msgtype);
958 entry = &channel_message_table[hdr->msgtype];
959 if (entry->handler_type == VMHT_BLOCKING) {
960 ctx = kmalloc(sizeof(*ctx), GFP_ATOMIC);
964 INIT_WORK(&ctx->work, vmbus_onmessage_work);
965 memcpy(&ctx->msg, msg, sizeof(*msg));
968 * The host can generate a rescind message while we
969 * may still be handling the original offer. We deal with
970 * this condition by ensuring the processing is done on the
973 switch (hdr->msgtype) {
974 case CHANNELMSG_RESCIND_CHANNELOFFER:
976 * If we are handling the rescind message;
977 * schedule the work on the global work queue.
979 schedule_work_on(vmbus_connection.connect_cpu,
983 case CHANNELMSG_OFFERCHANNEL:
984 atomic_inc(&vmbus_connection.offer_in_progress);
985 queue_work_on(vmbus_connection.connect_cpu,
986 vmbus_connection.work_queue,
991 queue_work(vmbus_connection.work_queue, &ctx->work);
994 entry->message_handler(hdr);
997 vmbus_signal_eom(msg, message_type);
1002 * Direct callback for channels using other deferred processing
1004 static void vmbus_channel_isr(struct vmbus_channel *channel)
1006 void (*callback_fn)(void *);
1008 callback_fn = READ_ONCE(channel->onchannel_callback);
1009 if (likely(callback_fn != NULL))
1010 (*callback_fn)(channel->channel_callback_context);
1014 * Schedule all channels with events pending
1016 static void vmbus_chan_sched(struct hv_per_cpu_context *hv_cpu)
1018 unsigned long *recv_int_page;
1021 if (vmbus_proto_version < VERSION_WIN8) {
1022 maxbits = MAX_NUM_CHANNELS_SUPPORTED;
1023 recv_int_page = vmbus_connection.recv_int_page;
1026 * When the host is win8 and beyond, the event page
1027 * can be directly checked to get the id of the channel
1028 * that has the interrupt pending.
1030 void *page_addr = hv_cpu->synic_event_page;
1031 union hv_synic_event_flags *event
1032 = (union hv_synic_event_flags *)page_addr +
1035 maxbits = HV_EVENT_FLAGS_COUNT;
1036 recv_int_page = event->flags;
1039 if (unlikely(!recv_int_page))
1042 for_each_set_bit(relid, recv_int_page, maxbits) {
1043 struct vmbus_channel *channel;
1045 if (!sync_test_and_clear_bit(relid, recv_int_page))
1048 /* Special case - vmbus channel protocol msg */
1054 /* Find channel based on relid */
1055 list_for_each_entry_rcu(channel, &hv_cpu->chan_list, percpu_list) {
1056 if (channel->offermsg.child_relid != relid)
1059 if (channel->rescind)
1062 trace_vmbus_chan_sched(channel);
1064 ++channel->interrupts;
1066 switch (channel->callback_mode) {
1068 vmbus_channel_isr(channel);
1071 case HV_CALL_BATCHED:
1072 hv_begin_read(&channel->inbound);
1074 case HV_CALL_DIRECT:
1075 tasklet_schedule(&channel->callback_event);
1083 static void vmbus_isr(void)
1085 struct hv_per_cpu_context *hv_cpu
1086 = this_cpu_ptr(hv_context.cpu_context);
1087 void *page_addr = hv_cpu->synic_event_page;
1088 struct hv_message *msg;
1089 union hv_synic_event_flags *event;
1090 bool handled = false;
1092 if (unlikely(page_addr == NULL))
1095 event = (union hv_synic_event_flags *)page_addr +
1098 * Check for events before checking for messages. This is the order
1099 * in which events and messages are checked in Windows guests on
1100 * Hyper-V, and the Windows team suggested we do the same.
1103 if ((vmbus_proto_version == VERSION_WS2008) ||
1104 (vmbus_proto_version == VERSION_WIN7)) {
1106 /* Since we are a child, we only need to check bit 0 */
1107 if (sync_test_and_clear_bit(0, event->flags))
1111 * Our host is win8 or above. The signaling mechanism
1112 * has changed and we can directly look at the event page.
1113 * If bit n is set then we have an interrup on the channel
1120 vmbus_chan_sched(hv_cpu);
1122 page_addr = hv_cpu->synic_message_page;
1123 msg = (struct hv_message *)page_addr + VMBUS_MESSAGE_SINT;
1125 /* Check if there are actual msgs to be processed */
1126 if (msg->header.message_type != HVMSG_NONE) {
1127 if (msg->header.message_type == HVMSG_TIMER_EXPIRED)
1128 hv_process_timer_expiration(msg, hv_cpu);
1130 tasklet_schedule(&hv_cpu->msg_dpc);
1133 add_interrupt_randomness(HYPERVISOR_CALLBACK_VECTOR, 0);
1137 * Boolean to control whether to report panic messages over Hyper-V.
1139 * It can be set via /proc/sys/kernel/hyperv/record_panic_msg
1141 static int sysctl_record_panic_msg = 1;
1144 * Callback from kmsg_dump. Grab as much as possible from the end of the kmsg
1145 * buffer and call into Hyper-V to transfer the data.
1147 static void hv_kmsg_dump(struct kmsg_dumper *dumper,
1148 enum kmsg_dump_reason reason)
1150 size_t bytes_written;
1151 phys_addr_t panic_pa;
1153 /* We are only interested in panics. */
1154 if ((reason != KMSG_DUMP_PANIC) || (!sysctl_record_panic_msg))
1157 panic_pa = virt_to_phys(hv_panic_page);
1160 * Write dump contents to the page. No need to synchronize; panic should
1161 * be single-threaded.
1163 kmsg_dump_get_buffer(dumper, true, hv_panic_page, PAGE_SIZE,
1166 hyperv_report_panic_msg(panic_pa, bytes_written);
1169 static struct kmsg_dumper hv_kmsg_dumper = {
1170 .dump = hv_kmsg_dump,
1173 static struct ctl_table_header *hv_ctl_table_hdr;
1178 * sysctl option to allow the user to control whether kmsg data should be
1179 * reported to Hyper-V on panic.
1181 static struct ctl_table hv_ctl_table[] = {
1183 .procname = "hyperv_record_panic_msg",
1184 .data = &sysctl_record_panic_msg,
1185 .maxlen = sizeof(int),
1187 .proc_handler = proc_dointvec_minmax,
1194 static struct ctl_table hv_root_table[] = {
1196 .procname = "kernel",
1198 .child = hv_ctl_table
1204 * vmbus_bus_init -Main vmbus driver initialization routine.
1207 * - initialize the vmbus driver context
1208 * - invoke the vmbus hv main init routine
1209 * - retrieve the channel offers
1211 static int vmbus_bus_init(void)
1215 /* Hypervisor initialization...setup hypercall page..etc */
1218 pr_err("Unable to initialize the hypervisor - 0x%x\n", ret);
1222 ret = bus_register(&hv_bus);
1226 hv_setup_vmbus_irq(vmbus_isr);
1228 ret = hv_synic_alloc();
1232 * Initialize the per-cpu interrupt state and
1233 * connect to the host.
1235 ret = cpuhp_setup_state(CPUHP_AP_ONLINE_DYN, "hyperv/vmbus:online",
1236 hv_synic_init, hv_synic_cleanup);
1239 hyperv_cpuhp_online = ret;
1241 ret = vmbus_connect();
1246 * Only register if the crash MSRs are available
1248 if (ms_hyperv.misc_features & HV_FEATURE_GUEST_CRASH_MSR_AVAILABLE) {
1249 u64 hyperv_crash_ctl;
1251 * Sysctl registration is not fatal, since by default
1252 * reporting is enabled.
1254 hv_ctl_table_hdr = register_sysctl_table(hv_root_table);
1255 if (!hv_ctl_table_hdr)
1256 pr_err("Hyper-V: sysctl table register error");
1259 * Register for panic kmsg callback only if the right
1260 * capability is supported by the hypervisor.
1262 hv_get_crash_ctl(hyperv_crash_ctl);
1263 if (hyperv_crash_ctl & HV_CRASH_CTL_CRASH_NOTIFY_MSG) {
1264 hv_panic_page = (void *)get_zeroed_page(GFP_KERNEL);
1265 if (hv_panic_page) {
1266 ret = kmsg_dump_register(&hv_kmsg_dumper);
1268 pr_err("Hyper-V: kmsg dump register "
1269 "error 0x%x\n", ret);
1271 pr_err("Hyper-V: panic message page memory "
1272 "allocation failed");
1275 register_die_notifier(&hyperv_die_block);
1276 atomic_notifier_chain_register(&panic_notifier_list,
1277 &hyperv_panic_block);
1280 vmbus_request_offers();
1285 cpuhp_remove_state(hyperv_cpuhp_online);
1288 hv_remove_vmbus_irq();
1290 bus_unregister(&hv_bus);
1291 free_page((unsigned long)hv_panic_page);
1292 unregister_sysctl_table(hv_ctl_table_hdr);
1293 hv_ctl_table_hdr = NULL;
1298 * __vmbus_child_driver_register() - Register a vmbus's driver
1299 * @hv_driver: Pointer to driver structure you want to register
1300 * @owner: owner module of the drv
1301 * @mod_name: module name string
1303 * Registers the given driver with Linux through the 'driver_register()' call
1304 * and sets up the hyper-v vmbus handling for this driver.
1305 * It will return the state of the 'driver_register()' call.
1308 int __vmbus_driver_register(struct hv_driver *hv_driver, struct module *owner, const char *mod_name)
1312 pr_info("registering driver %s\n", hv_driver->name);
1314 ret = vmbus_exists();
1318 hv_driver->driver.name = hv_driver->name;
1319 hv_driver->driver.owner = owner;
1320 hv_driver->driver.mod_name = mod_name;
1321 hv_driver->driver.bus = &hv_bus;
1323 spin_lock_init(&hv_driver->dynids.lock);
1324 INIT_LIST_HEAD(&hv_driver->dynids.list);
1326 ret = driver_register(&hv_driver->driver);
1330 EXPORT_SYMBOL_GPL(__vmbus_driver_register);
1333 * vmbus_driver_unregister() - Unregister a vmbus's driver
1334 * @hv_driver: Pointer to driver structure you want to
1337 * Un-register the given driver that was previous registered with a call to
1338 * vmbus_driver_register()
1340 void vmbus_driver_unregister(struct hv_driver *hv_driver)
1342 pr_info("unregistering driver %s\n", hv_driver->name);
1344 if (!vmbus_exists()) {
1345 driver_unregister(&hv_driver->driver);
1346 vmbus_free_dynids(hv_driver);
1349 EXPORT_SYMBOL_GPL(vmbus_driver_unregister);
1353 * Called when last reference to channel is gone.
1355 static void vmbus_chan_release(struct kobject *kobj)
1357 struct vmbus_channel *channel
1358 = container_of(kobj, struct vmbus_channel, kobj);
1360 kfree_rcu(channel, rcu);
1363 struct vmbus_chan_attribute {
1364 struct attribute attr;
1365 ssize_t (*show)(const struct vmbus_channel *chan, char *buf);
1366 ssize_t (*store)(struct vmbus_channel *chan,
1367 const char *buf, size_t count);
1369 #define VMBUS_CHAN_ATTR(_name, _mode, _show, _store) \
1370 struct vmbus_chan_attribute chan_attr_##_name \
1371 = __ATTR(_name, _mode, _show, _store)
1372 #define VMBUS_CHAN_ATTR_RW(_name) \
1373 struct vmbus_chan_attribute chan_attr_##_name = __ATTR_RW(_name)
1374 #define VMBUS_CHAN_ATTR_RO(_name) \
1375 struct vmbus_chan_attribute chan_attr_##_name = __ATTR_RO(_name)
1376 #define VMBUS_CHAN_ATTR_WO(_name) \
1377 struct vmbus_chan_attribute chan_attr_##_name = __ATTR_WO(_name)
1379 static ssize_t vmbus_chan_attr_show(struct kobject *kobj,
1380 struct attribute *attr, char *buf)
1382 const struct vmbus_chan_attribute *attribute
1383 = container_of(attr, struct vmbus_chan_attribute, attr);
1384 const struct vmbus_channel *chan
1385 = container_of(kobj, struct vmbus_channel, kobj);
1387 if (!attribute->show)
1390 if (chan->state != CHANNEL_OPENED_STATE)
1393 return attribute->show(chan, buf);
1396 static const struct sysfs_ops vmbus_chan_sysfs_ops = {
1397 .show = vmbus_chan_attr_show,
1400 static ssize_t out_mask_show(const struct vmbus_channel *channel, char *buf)
1402 const struct hv_ring_buffer_info *rbi = &channel->outbound;
1404 return sprintf(buf, "%u\n", rbi->ring_buffer->interrupt_mask);
1406 static VMBUS_CHAN_ATTR_RO(out_mask);
1408 static ssize_t in_mask_show(const struct vmbus_channel *channel, char *buf)
1410 const struct hv_ring_buffer_info *rbi = &channel->inbound;
1412 return sprintf(buf, "%u\n", rbi->ring_buffer->interrupt_mask);
1414 static VMBUS_CHAN_ATTR_RO(in_mask);
1416 static ssize_t read_avail_show(const struct vmbus_channel *channel, char *buf)
1418 const struct hv_ring_buffer_info *rbi = &channel->inbound;
1420 return sprintf(buf, "%u\n", hv_get_bytes_to_read(rbi));
1422 static VMBUS_CHAN_ATTR_RO(read_avail);
1424 static ssize_t write_avail_show(const struct vmbus_channel *channel, char *buf)
1426 const struct hv_ring_buffer_info *rbi = &channel->outbound;
1428 return sprintf(buf, "%u\n", hv_get_bytes_to_write(rbi));
1430 static VMBUS_CHAN_ATTR_RO(write_avail);
1432 static ssize_t show_target_cpu(const struct vmbus_channel *channel, char *buf)
1434 return sprintf(buf, "%u\n", channel->target_cpu);
1436 static VMBUS_CHAN_ATTR(cpu, S_IRUGO, show_target_cpu, NULL);
1438 static ssize_t channel_pending_show(const struct vmbus_channel *channel,
1441 return sprintf(buf, "%d\n",
1442 channel_pending(channel,
1443 vmbus_connection.monitor_pages[1]));
1445 static VMBUS_CHAN_ATTR(pending, S_IRUGO, channel_pending_show, NULL);
1447 static ssize_t channel_latency_show(const struct vmbus_channel *channel,
1450 return sprintf(buf, "%d\n",
1451 channel_latency(channel,
1452 vmbus_connection.monitor_pages[1]));
1454 static VMBUS_CHAN_ATTR(latency, S_IRUGO, channel_latency_show, NULL);
1456 static ssize_t channel_interrupts_show(const struct vmbus_channel *channel, char *buf)
1458 return sprintf(buf, "%llu\n", channel->interrupts);
1460 static VMBUS_CHAN_ATTR(interrupts, S_IRUGO, channel_interrupts_show, NULL);
1462 static ssize_t channel_events_show(const struct vmbus_channel *channel, char *buf)
1464 return sprintf(buf, "%llu\n", channel->sig_events);
1466 static VMBUS_CHAN_ATTR(events, S_IRUGO, channel_events_show, NULL);
1468 static ssize_t subchannel_monitor_id_show(const struct vmbus_channel *channel,
1471 return sprintf(buf, "%u\n", channel->offermsg.monitorid);
1473 static VMBUS_CHAN_ATTR(monitor_id, S_IRUGO, subchannel_monitor_id_show, NULL);
1475 static ssize_t subchannel_id_show(const struct vmbus_channel *channel,
1478 return sprintf(buf, "%u\n",
1479 channel->offermsg.offer.sub_channel_index);
1481 static VMBUS_CHAN_ATTR_RO(subchannel_id);
1483 static struct attribute *vmbus_chan_attrs[] = {
1484 &chan_attr_out_mask.attr,
1485 &chan_attr_in_mask.attr,
1486 &chan_attr_read_avail.attr,
1487 &chan_attr_write_avail.attr,
1488 &chan_attr_cpu.attr,
1489 &chan_attr_pending.attr,
1490 &chan_attr_latency.attr,
1491 &chan_attr_interrupts.attr,
1492 &chan_attr_events.attr,
1493 &chan_attr_monitor_id.attr,
1494 &chan_attr_subchannel_id.attr,
1498 static struct kobj_type vmbus_chan_ktype = {
1499 .sysfs_ops = &vmbus_chan_sysfs_ops,
1500 .release = vmbus_chan_release,
1501 .default_attrs = vmbus_chan_attrs,
1505 * vmbus_add_channel_kobj - setup a sub-directory under device/channels
1507 int vmbus_add_channel_kobj(struct hv_device *dev, struct vmbus_channel *channel)
1509 struct kobject *kobj = &channel->kobj;
1510 u32 relid = channel->offermsg.child_relid;
1513 kobj->kset = dev->channels_kset;
1514 ret = kobject_init_and_add(kobj, &vmbus_chan_ktype, NULL,
1519 kobject_uevent(kobj, KOBJ_ADD);
1525 * vmbus_device_create - Creates and registers a new child device
1528 struct hv_device *vmbus_device_create(const uuid_le *type,
1529 const uuid_le *instance,
1530 struct vmbus_channel *channel)
1532 struct hv_device *child_device_obj;
1534 child_device_obj = kzalloc(sizeof(struct hv_device), GFP_KERNEL);
1535 if (!child_device_obj) {
1536 pr_err("Unable to allocate device object for child device\n");
1540 child_device_obj->channel = channel;
1541 memcpy(&child_device_obj->dev_type, type, sizeof(uuid_le));
1542 memcpy(&child_device_obj->dev_instance, instance,
1544 child_device_obj->vendor_id = 0x1414; /* MSFT vendor ID */
1547 return child_device_obj;
1551 * vmbus_device_register - Register the child device
1553 int vmbus_device_register(struct hv_device *child_device_obj)
1555 struct kobject *kobj = &child_device_obj->device.kobj;
1558 dev_set_name(&child_device_obj->device, "%pUl",
1559 child_device_obj->channel->offermsg.offer.if_instance.b);
1561 child_device_obj->device.bus = &hv_bus;
1562 child_device_obj->device.parent = &hv_acpi_dev->dev;
1563 child_device_obj->device.release = vmbus_device_release;
1566 * Register with the LDM. This will kick off the driver/device
1567 * binding...which will eventually call vmbus_match() and vmbus_probe()
1569 ret = device_register(&child_device_obj->device);
1571 pr_err("Unable to register child device\n");
1575 child_device_obj->channels_kset = kset_create_and_add("channels",
1577 if (!child_device_obj->channels_kset) {
1579 goto err_dev_unregister;
1582 ret = vmbus_add_channel_kobj(child_device_obj,
1583 child_device_obj->channel);
1585 pr_err("Unable to register primary channeln");
1586 goto err_kset_unregister;
1591 err_kset_unregister:
1592 kset_unregister(child_device_obj->channels_kset);
1595 device_unregister(&child_device_obj->device);
1600 * vmbus_device_unregister - Remove the specified child device
1603 void vmbus_device_unregister(struct hv_device *device_obj)
1605 pr_debug("child device %s unregistered\n",
1606 dev_name(&device_obj->device));
1608 kset_unregister(device_obj->channels_kset);
1611 * Kick off the process of unregistering the device.
1612 * This will call vmbus_remove() and eventually vmbus_device_release()
1614 device_unregister(&device_obj->device);
1619 * VMBUS is an acpi enumerated device. Get the information we
1622 #define VTPM_BASE_ADDRESS 0xfed40000
1623 static acpi_status vmbus_walk_resources(struct acpi_resource *res, void *ctx)
1625 resource_size_t start = 0;
1626 resource_size_t end = 0;
1627 struct resource *new_res;
1628 struct resource **old_res = &hyperv_mmio;
1629 struct resource **prev_res = NULL;
1631 switch (res->type) {
1634 * "Address" descriptors are for bus windows. Ignore
1635 * "memory" descriptors, which are for registers on
1638 case ACPI_RESOURCE_TYPE_ADDRESS32:
1639 start = res->data.address32.address.minimum;
1640 end = res->data.address32.address.maximum;
1643 case ACPI_RESOURCE_TYPE_ADDRESS64:
1644 start = res->data.address64.address.minimum;
1645 end = res->data.address64.address.maximum;
1649 /* Unused resource type */
1654 * Ignore ranges that are below 1MB, as they're not
1655 * necessary or useful here.
1660 new_res = kzalloc(sizeof(*new_res), GFP_ATOMIC);
1662 return AE_NO_MEMORY;
1664 /* If this range overlaps the virtual TPM, truncate it. */
1665 if (end > VTPM_BASE_ADDRESS && start < VTPM_BASE_ADDRESS)
1666 end = VTPM_BASE_ADDRESS;
1668 new_res->name = "hyperv mmio";
1669 new_res->flags = IORESOURCE_MEM;
1670 new_res->start = start;
1674 * If two ranges are adjacent, merge them.
1682 if (((*old_res)->end + 1) == new_res->start) {
1683 (*old_res)->end = new_res->end;
1688 if ((*old_res)->start == new_res->end + 1) {
1689 (*old_res)->start = new_res->start;
1694 if ((*old_res)->start > new_res->end) {
1695 new_res->sibling = *old_res;
1697 (*prev_res)->sibling = new_res;
1703 old_res = &(*old_res)->sibling;
1710 static int vmbus_acpi_remove(struct acpi_device *device)
1712 struct resource *cur_res;
1713 struct resource *next_res;
1717 __release_region(hyperv_mmio, fb_mmio->start,
1718 resource_size(fb_mmio));
1722 for (cur_res = hyperv_mmio; cur_res; cur_res = next_res) {
1723 next_res = cur_res->sibling;
1731 static void vmbus_reserve_fb(void)
1735 * Make a claim for the frame buffer in the resource tree under the
1736 * first node, which will be the one below 4GB. The length seems to
1737 * be underreported, particularly in a Generation 1 VM. So start out
1738 * reserving a larger area and make it smaller until it succeeds.
1741 if (screen_info.lfb_base) {
1742 if (efi_enabled(EFI_BOOT))
1743 size = max_t(__u32, screen_info.lfb_size, 0x800000);
1745 size = max_t(__u32, screen_info.lfb_size, 0x4000000);
1747 for (; !fb_mmio && (size >= 0x100000); size >>= 1) {
1748 fb_mmio = __request_region(hyperv_mmio,
1749 screen_info.lfb_base, size,
1756 * vmbus_allocate_mmio() - Pick a memory-mapped I/O range.
1757 * @new: If successful, supplied a pointer to the
1758 * allocated MMIO space.
1759 * @device_obj: Identifies the caller
1760 * @min: Minimum guest physical address of the
1762 * @max: Maximum guest physical address
1763 * @size: Size of the range to be allocated
1764 * @align: Alignment of the range to be allocated
1765 * @fb_overlap_ok: Whether this allocation can be allowed
1766 * to overlap the video frame buffer.
1768 * This function walks the resources granted to VMBus by the
1769 * _CRS object in the ACPI namespace underneath the parent
1770 * "bridge" whether that's a root PCI bus in the Generation 1
1771 * case or a Module Device in the Generation 2 case. It then
1772 * attempts to allocate from the global MMIO pool in a way that
1773 * matches the constraints supplied in these parameters and by
1776 * Return: 0 on success, -errno on failure
1778 int vmbus_allocate_mmio(struct resource **new, struct hv_device *device_obj,
1779 resource_size_t min, resource_size_t max,
1780 resource_size_t size, resource_size_t align,
1783 struct resource *iter, *shadow;
1784 resource_size_t range_min, range_max, start;
1785 const char *dev_n = dev_name(&device_obj->device);
1789 down(&hyperv_mmio_lock);
1792 * If overlaps with frame buffers are allowed, then first attempt to
1793 * make the allocation from within the reserved region. Because it
1794 * is already reserved, no shadow allocation is necessary.
1796 if (fb_overlap_ok && fb_mmio && !(min > fb_mmio->end) &&
1797 !(max < fb_mmio->start)) {
1799 range_min = fb_mmio->start;
1800 range_max = fb_mmio->end;
1801 start = (range_min + align - 1) & ~(align - 1);
1802 for (; start + size - 1 <= range_max; start += align) {
1803 *new = request_mem_region_exclusive(start, size, dev_n);
1811 for (iter = hyperv_mmio; iter; iter = iter->sibling) {
1812 if ((iter->start >= max) || (iter->end <= min))
1815 range_min = iter->start;
1816 range_max = iter->end;
1817 start = (range_min + align - 1) & ~(align - 1);
1818 for (; start + size - 1 <= range_max; start += align) {
1819 shadow = __request_region(iter, start, size, NULL,
1824 *new = request_mem_region_exclusive(start, size, dev_n);
1826 shadow->name = (char *)*new;
1831 __release_region(iter, start, size);
1836 up(&hyperv_mmio_lock);
1839 EXPORT_SYMBOL_GPL(vmbus_allocate_mmio);
1842 * vmbus_free_mmio() - Free a memory-mapped I/O range.
1843 * @start: Base address of region to release.
1844 * @size: Size of the range to be allocated
1846 * This function releases anything requested by
1847 * vmbus_mmio_allocate().
1849 void vmbus_free_mmio(resource_size_t start, resource_size_t size)
1851 struct resource *iter;
1853 down(&hyperv_mmio_lock);
1854 for (iter = hyperv_mmio; iter; iter = iter->sibling) {
1855 if ((iter->start >= start + size) || (iter->end <= start))
1858 __release_region(iter, start, size);
1860 release_mem_region(start, size);
1861 up(&hyperv_mmio_lock);
1864 EXPORT_SYMBOL_GPL(vmbus_free_mmio);
1866 static int vmbus_acpi_add(struct acpi_device *device)
1869 int ret_val = -ENODEV;
1870 struct acpi_device *ancestor;
1872 hv_acpi_dev = device;
1874 result = acpi_walk_resources(device->handle, METHOD_NAME__CRS,
1875 vmbus_walk_resources, NULL);
1877 if (ACPI_FAILURE(result))
1880 * Some ancestor of the vmbus acpi device (Gen1 or Gen2
1881 * firmware) is the VMOD that has the mmio ranges. Get that.
1883 for (ancestor = device->parent; ancestor; ancestor = ancestor->parent) {
1884 result = acpi_walk_resources(ancestor->handle, METHOD_NAME__CRS,
1885 vmbus_walk_resources, NULL);
1887 if (ACPI_FAILURE(result))
1897 complete(&probe_event);
1899 vmbus_acpi_remove(device);
1903 static const struct acpi_device_id vmbus_acpi_device_ids[] = {
1908 MODULE_DEVICE_TABLE(acpi, vmbus_acpi_device_ids);
1910 static struct acpi_driver vmbus_acpi_driver = {
1912 .ids = vmbus_acpi_device_ids,
1914 .add = vmbus_acpi_add,
1915 .remove = vmbus_acpi_remove,
1919 static void hv_kexec_handler(void)
1921 hv_synic_clockevents_cleanup();
1922 vmbus_initiate_unload(false);
1923 vmbus_connection.conn_state = DISCONNECTED;
1924 /* Make sure conn_state is set as hv_synic_cleanup checks for it */
1926 cpuhp_remove_state(hyperv_cpuhp_online);
1930 static void hv_crash_handler(struct pt_regs *regs)
1932 vmbus_initiate_unload(true);
1934 * In crash handler we can't schedule synic cleanup for all CPUs,
1935 * doing the cleanup for current CPU only. This should be sufficient
1938 vmbus_connection.conn_state = DISCONNECTED;
1939 hv_synic_cleanup(smp_processor_id());
1943 static int __init hv_acpi_init(void)
1947 if (!hv_is_hyperv_initialized())
1950 init_completion(&probe_event);
1953 * Get ACPI resources first.
1955 ret = acpi_bus_register_driver(&vmbus_acpi_driver);
1960 t = wait_for_completion_timeout(&probe_event, 5*HZ);
1966 ret = vmbus_bus_init();
1970 hv_setup_kexec_handler(hv_kexec_handler);
1971 hv_setup_crash_handler(hv_crash_handler);
1976 acpi_bus_unregister_driver(&vmbus_acpi_driver);
1981 static void __exit vmbus_exit(void)
1985 hv_remove_kexec_handler();
1986 hv_remove_crash_handler();
1987 vmbus_connection.conn_state = DISCONNECTED;
1988 hv_synic_clockevents_cleanup();
1990 hv_remove_vmbus_irq();
1991 for_each_online_cpu(cpu) {
1992 struct hv_per_cpu_context *hv_cpu
1993 = per_cpu_ptr(hv_context.cpu_context, cpu);
1995 tasklet_kill(&hv_cpu->msg_dpc);
1997 vmbus_free_channels();
1999 if (ms_hyperv.misc_features & HV_FEATURE_GUEST_CRASH_MSR_AVAILABLE) {
2000 kmsg_dump_unregister(&hv_kmsg_dumper);
2001 unregister_die_notifier(&hyperv_die_block);
2002 atomic_notifier_chain_unregister(&panic_notifier_list,
2003 &hyperv_panic_block);
2006 free_page((unsigned long)hv_panic_page);
2007 unregister_sysctl_table(hv_ctl_table_hdr);
2008 hv_ctl_table_hdr = NULL;
2009 bus_unregister(&hv_bus);
2011 cpuhp_remove_state(hyperv_cpuhp_online);
2013 acpi_bus_unregister_driver(&vmbus_acpi_driver);
2017 MODULE_LICENSE("GPL");
2019 subsys_initcall(hv_acpi_init);
2020 module_exit(vmbus_exit);