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 <asm/hyperv.h>
38 #include <asm/hypervisor.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 "hyperv_vmbus.h"
46 static struct acpi_device *hv_acpi_dev;
48 static struct tasklet_struct msg_dpc;
49 static struct completion probe_event;
52 static void hyperv_report_panic(struct pt_regs *regs)
54 static bool panic_reported;
57 * We prefer to report panic on 'die' chain as we have proper
58 * registers to report, but if we miss it (e.g. on BUG()) we need
59 * to report it on 'panic'.
63 panic_reported = true;
65 wrmsrl(HV_X64_MSR_CRASH_P0, regs->ip);
66 wrmsrl(HV_X64_MSR_CRASH_P1, regs->ax);
67 wrmsrl(HV_X64_MSR_CRASH_P2, regs->bx);
68 wrmsrl(HV_X64_MSR_CRASH_P3, regs->cx);
69 wrmsrl(HV_X64_MSR_CRASH_P4, regs->dx);
72 * Let Hyper-V know there is crash data available
74 wrmsrl(HV_X64_MSR_CRASH_CTL, HV_CRASH_CTL_CRASH_NOTIFY);
77 static int hyperv_panic_event(struct notifier_block *nb, unsigned long val,
82 regs = current_pt_regs();
84 hyperv_report_panic(regs);
88 static int hyperv_die_event(struct notifier_block *nb, unsigned long val,
91 struct die_args *die = (struct die_args *)args;
92 struct pt_regs *regs = die->regs;
94 hyperv_report_panic(regs);
98 static struct notifier_block hyperv_die_block = {
99 .notifier_call = hyperv_die_event,
101 static struct notifier_block hyperv_panic_block = {
102 .notifier_call = hyperv_panic_event,
105 struct resource *hyperv_mmio;
107 static int vmbus_exists(void)
109 if (hv_acpi_dev == NULL)
115 #define VMBUS_ALIAS_LEN ((sizeof((struct hv_vmbus_device_id *)0)->guid) * 2)
116 static void print_alias_name(struct hv_device *hv_dev, char *alias_name)
119 for (i = 0; i < VMBUS_ALIAS_LEN; i += 2)
120 sprintf(&alias_name[i], "%02x", hv_dev->dev_type.b[i/2]);
123 static u8 channel_monitor_group(struct vmbus_channel *channel)
125 return (u8)channel->offermsg.monitorid / 32;
128 static u8 channel_monitor_offset(struct vmbus_channel *channel)
130 return (u8)channel->offermsg.monitorid % 32;
133 static u32 channel_pending(struct vmbus_channel *channel,
134 struct hv_monitor_page *monitor_page)
136 u8 monitor_group = channel_monitor_group(channel);
137 return monitor_page->trigger_group[monitor_group].pending;
140 static u32 channel_latency(struct vmbus_channel *channel,
141 struct hv_monitor_page *monitor_page)
143 u8 monitor_group = channel_monitor_group(channel);
144 u8 monitor_offset = channel_monitor_offset(channel);
145 return monitor_page->latency[monitor_group][monitor_offset];
148 static u32 channel_conn_id(struct vmbus_channel *channel,
149 struct hv_monitor_page *monitor_page)
151 u8 monitor_group = channel_monitor_group(channel);
152 u8 monitor_offset = channel_monitor_offset(channel);
153 return monitor_page->parameter[monitor_group][monitor_offset].connectionid.u.id;
156 static ssize_t id_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->offermsg.child_relid);
165 static DEVICE_ATTR_RO(id);
167 static ssize_t state_show(struct device *dev, struct device_attribute *dev_attr,
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->state);
176 static DEVICE_ATTR_RO(state);
178 static ssize_t monitor_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, "%d\n", hv_dev->channel->offermsg.monitorid);
187 static DEVICE_ATTR_RO(monitor_id);
189 static ssize_t class_id_show(struct device *dev,
190 struct device_attribute *dev_attr, char *buf)
192 struct hv_device *hv_dev = device_to_hv_device(dev);
194 if (!hv_dev->channel)
196 return sprintf(buf, "{%pUl}\n",
197 hv_dev->channel->offermsg.offer.if_type.b);
199 static DEVICE_ATTR_RO(class_id);
201 static ssize_t device_id_show(struct device *dev,
202 struct device_attribute *dev_attr, char *buf)
204 struct hv_device *hv_dev = device_to_hv_device(dev);
206 if (!hv_dev->channel)
208 return sprintf(buf, "{%pUl}\n",
209 hv_dev->channel->offermsg.offer.if_instance.b);
211 static DEVICE_ATTR_RO(device_id);
213 static ssize_t modalias_show(struct device *dev,
214 struct device_attribute *dev_attr, char *buf)
216 struct hv_device *hv_dev = device_to_hv_device(dev);
217 char alias_name[VMBUS_ALIAS_LEN + 1];
219 print_alias_name(hv_dev, alias_name);
220 return sprintf(buf, "vmbus:%s\n", alias_name);
222 static DEVICE_ATTR_RO(modalias);
224 static ssize_t server_monitor_pending_show(struct device *dev,
225 struct device_attribute *dev_attr,
228 struct hv_device *hv_dev = device_to_hv_device(dev);
230 if (!hv_dev->channel)
232 return sprintf(buf, "%d\n",
233 channel_pending(hv_dev->channel,
234 vmbus_connection.monitor_pages[1]));
236 static DEVICE_ATTR_RO(server_monitor_pending);
238 static ssize_t client_monitor_pending_show(struct device *dev,
239 struct device_attribute *dev_attr,
242 struct hv_device *hv_dev = device_to_hv_device(dev);
244 if (!hv_dev->channel)
246 return sprintf(buf, "%d\n",
247 channel_pending(hv_dev->channel,
248 vmbus_connection.monitor_pages[1]));
250 static DEVICE_ATTR_RO(client_monitor_pending);
252 static ssize_t server_monitor_latency_show(struct device *dev,
253 struct device_attribute *dev_attr,
256 struct hv_device *hv_dev = device_to_hv_device(dev);
258 if (!hv_dev->channel)
260 return sprintf(buf, "%d\n",
261 channel_latency(hv_dev->channel,
262 vmbus_connection.monitor_pages[0]));
264 static DEVICE_ATTR_RO(server_monitor_latency);
266 static ssize_t client_monitor_latency_show(struct device *dev,
267 struct device_attribute *dev_attr,
270 struct hv_device *hv_dev = device_to_hv_device(dev);
272 if (!hv_dev->channel)
274 return sprintf(buf, "%d\n",
275 channel_latency(hv_dev->channel,
276 vmbus_connection.monitor_pages[1]));
278 static DEVICE_ATTR_RO(client_monitor_latency);
280 static ssize_t server_monitor_conn_id_show(struct device *dev,
281 struct device_attribute *dev_attr,
284 struct hv_device *hv_dev = device_to_hv_device(dev);
286 if (!hv_dev->channel)
288 return sprintf(buf, "%d\n",
289 channel_conn_id(hv_dev->channel,
290 vmbus_connection.monitor_pages[0]));
292 static DEVICE_ATTR_RO(server_monitor_conn_id);
294 static ssize_t client_monitor_conn_id_show(struct device *dev,
295 struct device_attribute *dev_attr,
298 struct hv_device *hv_dev = device_to_hv_device(dev);
300 if (!hv_dev->channel)
302 return sprintf(buf, "%d\n",
303 channel_conn_id(hv_dev->channel,
304 vmbus_connection.monitor_pages[1]));
306 static DEVICE_ATTR_RO(client_monitor_conn_id);
308 static ssize_t out_intr_mask_show(struct device *dev,
309 struct device_attribute *dev_attr, char *buf)
311 struct hv_device *hv_dev = device_to_hv_device(dev);
312 struct hv_ring_buffer_debug_info outbound;
314 if (!hv_dev->channel)
316 hv_ringbuffer_get_debuginfo(&hv_dev->channel->outbound, &outbound);
317 return sprintf(buf, "%d\n", outbound.current_interrupt_mask);
319 static DEVICE_ATTR_RO(out_intr_mask);
321 static ssize_t out_read_index_show(struct device *dev,
322 struct device_attribute *dev_attr, char *buf)
324 struct hv_device *hv_dev = device_to_hv_device(dev);
325 struct hv_ring_buffer_debug_info outbound;
327 if (!hv_dev->channel)
329 hv_ringbuffer_get_debuginfo(&hv_dev->channel->outbound, &outbound);
330 return sprintf(buf, "%d\n", outbound.current_read_index);
332 static DEVICE_ATTR_RO(out_read_index);
334 static ssize_t out_write_index_show(struct device *dev,
335 struct device_attribute *dev_attr,
338 struct hv_device *hv_dev = device_to_hv_device(dev);
339 struct hv_ring_buffer_debug_info outbound;
341 if (!hv_dev->channel)
343 hv_ringbuffer_get_debuginfo(&hv_dev->channel->outbound, &outbound);
344 return sprintf(buf, "%d\n", outbound.current_write_index);
346 static DEVICE_ATTR_RO(out_write_index);
348 static ssize_t out_read_bytes_avail_show(struct device *dev,
349 struct device_attribute *dev_attr,
352 struct hv_device *hv_dev = device_to_hv_device(dev);
353 struct hv_ring_buffer_debug_info outbound;
355 if (!hv_dev->channel)
357 hv_ringbuffer_get_debuginfo(&hv_dev->channel->outbound, &outbound);
358 return sprintf(buf, "%d\n", outbound.bytes_avail_toread);
360 static DEVICE_ATTR_RO(out_read_bytes_avail);
362 static ssize_t out_write_bytes_avail_show(struct device *dev,
363 struct device_attribute *dev_attr,
366 struct hv_device *hv_dev = device_to_hv_device(dev);
367 struct hv_ring_buffer_debug_info outbound;
369 if (!hv_dev->channel)
371 hv_ringbuffer_get_debuginfo(&hv_dev->channel->outbound, &outbound);
372 return sprintf(buf, "%d\n", outbound.bytes_avail_towrite);
374 static DEVICE_ATTR_RO(out_write_bytes_avail);
376 static ssize_t in_intr_mask_show(struct device *dev,
377 struct device_attribute *dev_attr, char *buf)
379 struct hv_device *hv_dev = device_to_hv_device(dev);
380 struct hv_ring_buffer_debug_info inbound;
382 if (!hv_dev->channel)
384 hv_ringbuffer_get_debuginfo(&hv_dev->channel->inbound, &inbound);
385 return sprintf(buf, "%d\n", inbound.current_interrupt_mask);
387 static DEVICE_ATTR_RO(in_intr_mask);
389 static ssize_t in_read_index_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 hv_ringbuffer_get_debuginfo(&hv_dev->channel->inbound, &inbound);
398 return sprintf(buf, "%d\n", inbound.current_read_index);
400 static DEVICE_ATTR_RO(in_read_index);
402 static ssize_t in_write_index_show(struct device *dev,
403 struct device_attribute *dev_attr, char *buf)
405 struct hv_device *hv_dev = device_to_hv_device(dev);
406 struct hv_ring_buffer_debug_info inbound;
408 if (!hv_dev->channel)
410 hv_ringbuffer_get_debuginfo(&hv_dev->channel->inbound, &inbound);
411 return sprintf(buf, "%d\n", inbound.current_write_index);
413 static DEVICE_ATTR_RO(in_write_index);
415 static ssize_t in_read_bytes_avail_show(struct device *dev,
416 struct device_attribute *dev_attr,
419 struct hv_device *hv_dev = device_to_hv_device(dev);
420 struct hv_ring_buffer_debug_info inbound;
422 if (!hv_dev->channel)
424 hv_ringbuffer_get_debuginfo(&hv_dev->channel->inbound, &inbound);
425 return sprintf(buf, "%d\n", inbound.bytes_avail_toread);
427 static DEVICE_ATTR_RO(in_read_bytes_avail);
429 static ssize_t in_write_bytes_avail_show(struct device *dev,
430 struct device_attribute *dev_attr,
433 struct hv_device *hv_dev = device_to_hv_device(dev);
434 struct hv_ring_buffer_debug_info inbound;
436 if (!hv_dev->channel)
438 hv_ringbuffer_get_debuginfo(&hv_dev->channel->inbound, &inbound);
439 return sprintf(buf, "%d\n", inbound.bytes_avail_towrite);
441 static DEVICE_ATTR_RO(in_write_bytes_avail);
443 static ssize_t channel_vp_mapping_show(struct device *dev,
444 struct device_attribute *dev_attr,
447 struct hv_device *hv_dev = device_to_hv_device(dev);
448 struct vmbus_channel *channel = hv_dev->channel, *cur_sc;
450 int buf_size = PAGE_SIZE, n_written, tot_written;
451 struct list_head *cur;
456 tot_written = snprintf(buf, buf_size, "%u:%u\n",
457 channel->offermsg.child_relid, channel->target_cpu);
459 spin_lock_irqsave(&channel->lock, flags);
461 list_for_each(cur, &channel->sc_list) {
462 if (tot_written >= buf_size - 1)
465 cur_sc = list_entry(cur, struct vmbus_channel, sc_list);
466 n_written = scnprintf(buf + tot_written,
467 buf_size - tot_written,
469 cur_sc->offermsg.child_relid,
471 tot_written += n_written;
474 spin_unlock_irqrestore(&channel->lock, flags);
478 static DEVICE_ATTR_RO(channel_vp_mapping);
480 static ssize_t vendor_show(struct device *dev,
481 struct device_attribute *dev_attr,
484 struct hv_device *hv_dev = device_to_hv_device(dev);
485 return sprintf(buf, "0x%x\n", hv_dev->vendor_id);
487 static DEVICE_ATTR_RO(vendor);
489 static ssize_t device_show(struct device *dev,
490 struct device_attribute *dev_attr,
493 struct hv_device *hv_dev = device_to_hv_device(dev);
494 return sprintf(buf, "0x%x\n", hv_dev->device_id);
496 static DEVICE_ATTR_RO(device);
498 /* Set up per device attributes in /sys/bus/vmbus/devices/<bus device> */
499 static struct attribute *vmbus_attrs[] = {
501 &dev_attr_state.attr,
502 &dev_attr_monitor_id.attr,
503 &dev_attr_class_id.attr,
504 &dev_attr_device_id.attr,
505 &dev_attr_modalias.attr,
506 &dev_attr_server_monitor_pending.attr,
507 &dev_attr_client_monitor_pending.attr,
508 &dev_attr_server_monitor_latency.attr,
509 &dev_attr_client_monitor_latency.attr,
510 &dev_attr_server_monitor_conn_id.attr,
511 &dev_attr_client_monitor_conn_id.attr,
512 &dev_attr_out_intr_mask.attr,
513 &dev_attr_out_read_index.attr,
514 &dev_attr_out_write_index.attr,
515 &dev_attr_out_read_bytes_avail.attr,
516 &dev_attr_out_write_bytes_avail.attr,
517 &dev_attr_in_intr_mask.attr,
518 &dev_attr_in_read_index.attr,
519 &dev_attr_in_write_index.attr,
520 &dev_attr_in_read_bytes_avail.attr,
521 &dev_attr_in_write_bytes_avail.attr,
522 &dev_attr_channel_vp_mapping.attr,
523 &dev_attr_vendor.attr,
524 &dev_attr_device.attr,
527 ATTRIBUTE_GROUPS(vmbus);
530 * vmbus_uevent - add uevent for our device
532 * This routine is invoked when a device is added or removed on the vmbus to
533 * generate a uevent to udev in the userspace. The udev will then look at its
534 * rule and the uevent generated here to load the appropriate driver
536 * The alias string will be of the form vmbus:guid where guid is the string
537 * representation of the device guid (each byte of the guid will be
538 * represented with two hex characters.
540 static int vmbus_uevent(struct device *device, struct kobj_uevent_env *env)
542 struct hv_device *dev = device_to_hv_device(device);
544 char alias_name[VMBUS_ALIAS_LEN + 1];
546 print_alias_name(dev, alias_name);
547 ret = add_uevent_var(env, "MODALIAS=vmbus:%s", alias_name);
551 static const uuid_le null_guid;
553 static inline bool is_null_guid(const uuid_le *guid)
555 if (uuid_le_cmp(*guid, null_guid))
561 * Return a matching hv_vmbus_device_id pointer.
562 * If there is no match, return NULL.
564 static const struct hv_vmbus_device_id *hv_vmbus_get_id(
565 const struct hv_vmbus_device_id *id,
568 for (; !is_null_guid(&id->guid); id++)
569 if (!uuid_le_cmp(id->guid, *guid))
578 * vmbus_match - Attempt to match the specified device to the specified driver
580 static int vmbus_match(struct device *device, struct device_driver *driver)
582 struct hv_driver *drv = drv_to_hv_drv(driver);
583 struct hv_device *hv_dev = device_to_hv_device(device);
585 /* The hv_sock driver handles all hv_sock offers. */
586 if (is_hvsock_channel(hv_dev->channel))
589 if (hv_vmbus_get_id(drv->id_table, &hv_dev->dev_type))
596 * vmbus_probe - Add the new vmbus's child device
598 static int vmbus_probe(struct device *child_device)
601 struct hv_driver *drv =
602 drv_to_hv_drv(child_device->driver);
603 struct hv_device *dev = device_to_hv_device(child_device);
604 const struct hv_vmbus_device_id *dev_id;
606 dev_id = hv_vmbus_get_id(drv->id_table, &dev->dev_type);
608 ret = drv->probe(dev, dev_id);
610 pr_err("probe failed for device %s (%d)\n",
611 dev_name(child_device), ret);
614 pr_err("probe not set for driver %s\n",
615 dev_name(child_device));
622 * vmbus_remove - Remove a vmbus device
624 static int vmbus_remove(struct device *child_device)
626 struct hv_driver *drv;
627 struct hv_device *dev = device_to_hv_device(child_device);
629 if (child_device->driver) {
630 drv = drv_to_hv_drv(child_device->driver);
640 * vmbus_shutdown - Shutdown a vmbus device
642 static void vmbus_shutdown(struct device *child_device)
644 struct hv_driver *drv;
645 struct hv_device *dev = device_to_hv_device(child_device);
648 /* The device may not be attached yet */
649 if (!child_device->driver)
652 drv = drv_to_hv_drv(child_device->driver);
662 * vmbus_device_release - Final callback release of the vmbus child device
664 static void vmbus_device_release(struct device *device)
666 struct hv_device *hv_dev = device_to_hv_device(device);
667 struct vmbus_channel *channel = hv_dev->channel;
669 hv_process_channel_removal(channel,
670 channel->offermsg.child_relid);
675 /* The one and only one */
676 static struct bus_type hv_bus = {
678 .match = vmbus_match,
679 .shutdown = vmbus_shutdown,
680 .remove = vmbus_remove,
681 .probe = vmbus_probe,
682 .uevent = vmbus_uevent,
683 .dev_groups = vmbus_groups,
686 struct onmessage_work_context {
687 struct work_struct work;
688 struct hv_message msg;
691 static void vmbus_onmessage_work(struct work_struct *work)
693 struct onmessage_work_context *ctx;
695 /* Do not process messages if we're in DISCONNECTED state */
696 if (vmbus_connection.conn_state == DISCONNECTED)
699 ctx = container_of(work, struct onmessage_work_context,
701 vmbus_onmessage(&ctx->msg);
705 static void hv_process_timer_expiration(struct hv_message *msg, int cpu)
707 struct clock_event_device *dev = hv_context.clk_evt[cpu];
709 if (dev->event_handler)
710 dev->event_handler(dev);
712 msg->header.message_type = HVMSG_NONE;
715 * Make sure the write to MessageType (ie set to
716 * HVMSG_NONE) happens before we read the
717 * MessagePending and EOMing. Otherwise, the EOMing
718 * will not deliver any more messages since there is
723 if (msg->header.message_flags.msg_pending) {
725 * This will cause message queue rescan to
726 * possibly deliver another msg from the
729 wrmsrl(HV_X64_MSR_EOM, 0);
733 static void vmbus_on_msg_dpc(unsigned long data)
735 int cpu = smp_processor_id();
736 void *page_addr = hv_context.synic_message_page[cpu];
737 struct hv_message *msg = (struct hv_message *)page_addr +
739 struct vmbus_channel_message_header *hdr;
740 struct vmbus_channel_message_table_entry *entry;
741 struct onmessage_work_context *ctx;
744 if (msg->header.message_type == HVMSG_NONE)
748 hdr = (struct vmbus_channel_message_header *)msg->u.payload;
750 if (hdr->msgtype >= CHANNELMSG_COUNT) {
751 WARN_ONCE(1, "unknown msgtype=%d\n", hdr->msgtype);
755 entry = &channel_message_table[hdr->msgtype];
756 if (entry->handler_type == VMHT_BLOCKING) {
757 ctx = kmalloc(sizeof(*ctx), GFP_ATOMIC);
761 INIT_WORK(&ctx->work, vmbus_onmessage_work);
762 memcpy(&ctx->msg, msg, sizeof(*msg));
764 queue_work(vmbus_connection.work_queue, &ctx->work);
766 entry->message_handler(hdr);
769 msg->header.message_type = HVMSG_NONE;
772 * Make sure the write to MessageType (ie set to
773 * HVMSG_NONE) happens before we read the
774 * MessagePending and EOMing. Otherwise, the EOMing
775 * will not deliver any more messages since there is
780 if (msg->header.message_flags.msg_pending) {
782 * This will cause message queue rescan to
783 * possibly deliver another msg from the
786 wrmsrl(HV_X64_MSR_EOM, 0);
791 static void vmbus_isr(void)
793 int cpu = smp_processor_id();
795 struct hv_message *msg;
796 union hv_synic_event_flags *event;
797 bool handled = false;
799 page_addr = hv_context.synic_event_page[cpu];
800 if (page_addr == NULL)
803 event = (union hv_synic_event_flags *)page_addr +
806 * Check for events before checking for messages. This is the order
807 * in which events and messages are checked in Windows guests on
808 * Hyper-V, and the Windows team suggested we do the same.
811 if ((vmbus_proto_version == VERSION_WS2008) ||
812 (vmbus_proto_version == VERSION_WIN7)) {
814 /* Since we are a child, we only need to check bit 0 */
815 if (sync_test_and_clear_bit(0,
816 (unsigned long *) &event->flags32[0])) {
821 * Our host is win8 or above. The signaling mechanism
822 * has changed and we can directly look at the event page.
823 * If bit n is set then we have an interrup on the channel
830 tasklet_schedule(hv_context.event_dpc[cpu]);
833 page_addr = hv_context.synic_message_page[cpu];
834 msg = (struct hv_message *)page_addr + VMBUS_MESSAGE_SINT;
836 /* Check if there are actual msgs to be processed */
837 if (msg->header.message_type != HVMSG_NONE) {
838 if (msg->header.message_type == HVMSG_TIMER_EXPIRED)
839 hv_process_timer_expiration(msg, cpu);
841 tasklet_schedule(&msg_dpc);
847 * vmbus_bus_init -Main vmbus driver initialization routine.
850 * - initialize the vmbus driver context
851 * - invoke the vmbus hv main init routine
852 * - retrieve the channel offers
854 static int vmbus_bus_init(void)
858 /* Hypervisor initialization...setup hypercall page..etc */
861 pr_err("Unable to initialize the hypervisor - 0x%x\n", ret);
865 tasklet_init(&msg_dpc, vmbus_on_msg_dpc, 0);
867 ret = bus_register(&hv_bus);
871 hv_setup_vmbus_irq(vmbus_isr);
873 ret = hv_synic_alloc();
877 * Initialize the per-cpu interrupt state and
878 * connect to the host.
880 on_each_cpu(hv_synic_init, NULL, 1);
881 ret = vmbus_connect();
885 if (vmbus_proto_version > VERSION_WIN7)
886 cpu_hotplug_disable();
889 * Only register if the crash MSRs are available
891 if (ms_hyperv.misc_features & HV_FEATURE_GUEST_CRASH_MSR_AVAILABLE) {
892 register_die_notifier(&hyperv_die_block);
893 atomic_notifier_chain_register(&panic_notifier_list,
894 &hyperv_panic_block);
897 vmbus_request_offers();
902 on_each_cpu(hv_synic_cleanup, NULL, 1);
905 hv_remove_vmbus_irq();
907 bus_unregister(&hv_bus);
916 * __vmbus_child_driver_register() - Register a vmbus's driver
917 * @hv_driver: Pointer to driver structure you want to register
918 * @owner: owner module of the drv
919 * @mod_name: module name string
921 * Registers the given driver with Linux through the 'driver_register()' call
922 * and sets up the hyper-v vmbus handling for this driver.
923 * It will return the state of the 'driver_register()' call.
926 int __vmbus_driver_register(struct hv_driver *hv_driver, struct module *owner, const char *mod_name)
930 pr_info("registering driver %s\n", hv_driver->name);
932 ret = vmbus_exists();
936 hv_driver->driver.name = hv_driver->name;
937 hv_driver->driver.owner = owner;
938 hv_driver->driver.mod_name = mod_name;
939 hv_driver->driver.bus = &hv_bus;
941 ret = driver_register(&hv_driver->driver);
945 EXPORT_SYMBOL_GPL(__vmbus_driver_register);
948 * vmbus_driver_unregister() - Unregister a vmbus's driver
949 * @hv_driver: Pointer to driver structure you want to
952 * Un-register the given driver that was previous registered with a call to
953 * vmbus_driver_register()
955 void vmbus_driver_unregister(struct hv_driver *hv_driver)
957 pr_info("unregistering driver %s\n", hv_driver->name);
960 driver_unregister(&hv_driver->driver);
962 EXPORT_SYMBOL_GPL(vmbus_driver_unregister);
965 * vmbus_device_create - Creates and registers a new child device
968 struct hv_device *vmbus_device_create(const uuid_le *type,
969 const uuid_le *instance,
970 struct vmbus_channel *channel)
972 struct hv_device *child_device_obj;
974 child_device_obj = kzalloc(sizeof(struct hv_device), GFP_KERNEL);
975 if (!child_device_obj) {
976 pr_err("Unable to allocate device object for child device\n");
980 child_device_obj->channel = channel;
981 memcpy(&child_device_obj->dev_type, type, sizeof(uuid_le));
982 memcpy(&child_device_obj->dev_instance, instance,
984 child_device_obj->vendor_id = 0x1414; /* MSFT vendor ID */
987 return child_device_obj;
991 * vmbus_device_register - Register the child device
993 int vmbus_device_register(struct hv_device *child_device_obj)
997 dev_set_name(&child_device_obj->device, "vmbus_%d",
998 child_device_obj->channel->id);
1000 child_device_obj->device.bus = &hv_bus;
1001 child_device_obj->device.parent = &hv_acpi_dev->dev;
1002 child_device_obj->device.release = vmbus_device_release;
1005 * Register with the LDM. This will kick off the driver/device
1006 * binding...which will eventually call vmbus_match() and vmbus_probe()
1008 ret = device_register(&child_device_obj->device);
1011 pr_err("Unable to register child device\n");
1013 pr_debug("child device %s registered\n",
1014 dev_name(&child_device_obj->device));
1020 * vmbus_device_unregister - Remove the specified child device
1023 void vmbus_device_unregister(struct hv_device *device_obj)
1025 pr_debug("child device %s unregistered\n",
1026 dev_name(&device_obj->device));
1029 * Kick off the process of unregistering the device.
1030 * This will call vmbus_remove() and eventually vmbus_device_release()
1032 device_unregister(&device_obj->device);
1037 * VMBUS is an acpi enumerated device. Get the information we
1040 #define VTPM_BASE_ADDRESS 0xfed40000
1041 static acpi_status vmbus_walk_resources(struct acpi_resource *res, void *ctx)
1043 resource_size_t start = 0;
1044 resource_size_t end = 0;
1045 struct resource *new_res;
1046 struct resource **old_res = &hyperv_mmio;
1047 struct resource **prev_res = NULL;
1049 switch (res->type) {
1052 * "Address" descriptors are for bus windows. Ignore
1053 * "memory" descriptors, which are for registers on
1056 case ACPI_RESOURCE_TYPE_ADDRESS32:
1057 start = res->data.address32.address.minimum;
1058 end = res->data.address32.address.maximum;
1061 case ACPI_RESOURCE_TYPE_ADDRESS64:
1062 start = res->data.address64.address.minimum;
1063 end = res->data.address64.address.maximum;
1067 /* Unused resource type */
1072 * Ignore ranges that are below 1MB, as they're not
1073 * necessary or useful here.
1078 new_res = kzalloc(sizeof(*new_res), GFP_ATOMIC);
1080 return AE_NO_MEMORY;
1082 /* If this range overlaps the virtual TPM, truncate it. */
1083 if (end > VTPM_BASE_ADDRESS && start < VTPM_BASE_ADDRESS)
1084 end = VTPM_BASE_ADDRESS;
1086 new_res->name = "hyperv mmio";
1087 new_res->flags = IORESOURCE_MEM;
1088 new_res->start = start;
1092 * Stick ranges from higher in address space at the front of the list.
1093 * If two ranges are adjacent, merge them.
1101 if (((*old_res)->end + 1) == new_res->start) {
1102 (*old_res)->end = new_res->end;
1107 if ((*old_res)->start == new_res->end + 1) {
1108 (*old_res)->start = new_res->start;
1113 if ((*old_res)->end < new_res->start) {
1114 new_res->sibling = *old_res;
1116 (*prev_res)->sibling = new_res;
1122 old_res = &(*old_res)->sibling;
1129 static int vmbus_acpi_remove(struct acpi_device *device)
1131 struct resource *cur_res;
1132 struct resource *next_res;
1135 for (cur_res = hyperv_mmio; cur_res; cur_res = next_res) {
1136 next_res = cur_res->sibling;
1145 * vmbus_allocate_mmio() - Pick a memory-mapped I/O range.
1146 * @new: If successful, supplied a pointer to the
1147 * allocated MMIO space.
1148 * @device_obj: Identifies the caller
1149 * @min: Minimum guest physical address of the
1151 * @max: Maximum guest physical address
1152 * @size: Size of the range to be allocated
1153 * @align: Alignment of the range to be allocated
1154 * @fb_overlap_ok: Whether this allocation can be allowed
1155 * to overlap the video frame buffer.
1157 * This function walks the resources granted to VMBus by the
1158 * _CRS object in the ACPI namespace underneath the parent
1159 * "bridge" whether that's a root PCI bus in the Generation 1
1160 * case or a Module Device in the Generation 2 case. It then
1161 * attempts to allocate from the global MMIO pool in a way that
1162 * matches the constraints supplied in these parameters and by
1165 * Return: 0 on success, -errno on failure
1167 int vmbus_allocate_mmio(struct resource **new, struct hv_device *device_obj,
1168 resource_size_t min, resource_size_t max,
1169 resource_size_t size, resource_size_t align,
1172 struct resource *iter;
1173 resource_size_t range_min, range_max, start, local_min, local_max;
1174 const char *dev_n = dev_name(&device_obj->device);
1175 u32 fb_end = screen_info.lfb_base + (screen_info.lfb_size << 1);
1178 for (iter = hyperv_mmio; iter; iter = iter->sibling) {
1179 if ((iter->start >= max) || (iter->end <= min))
1182 range_min = iter->start;
1183 range_max = iter->end;
1185 /* If this range overlaps the frame buffer, split it into
1187 for (i = 0; i < 2; i++) {
1188 local_min = range_min;
1189 local_max = range_max;
1190 if (fb_overlap_ok || (range_min >= fb_end) ||
1191 (range_max <= screen_info.lfb_base)) {
1194 if ((range_min <= screen_info.lfb_base) &&
1195 (range_max >= screen_info.lfb_base)) {
1197 * The frame buffer is in this window,
1198 * so trim this into the part that
1199 * preceeds the frame buffer.
1201 local_max = screen_info.lfb_base - 1;
1209 start = (local_min + align - 1) & ~(align - 1);
1210 for (; start + size - 1 <= local_max; start += align) {
1211 *new = request_mem_region_exclusive(start, size,
1221 EXPORT_SYMBOL_GPL(vmbus_allocate_mmio);
1224 * vmbus_cpu_number_to_vp_number() - Map CPU to VP.
1225 * @cpu_number: CPU number in Linux terms
1227 * This function returns the mapping between the Linux processor
1228 * number and the hypervisor's virtual processor number, useful
1229 * in making hypercalls and such that talk about specific
1232 * Return: Virtual processor number in Hyper-V terms
1234 int vmbus_cpu_number_to_vp_number(int cpu_number)
1236 return hv_context.vp_index[cpu_number];
1238 EXPORT_SYMBOL_GPL(vmbus_cpu_number_to_vp_number);
1240 static int vmbus_acpi_add(struct acpi_device *device)
1243 int ret_val = -ENODEV;
1244 struct acpi_device *ancestor;
1246 hv_acpi_dev = device;
1248 result = acpi_walk_resources(device->handle, METHOD_NAME__CRS,
1249 vmbus_walk_resources, NULL);
1251 if (ACPI_FAILURE(result))
1254 * Some ancestor of the vmbus acpi device (Gen1 or Gen2
1255 * firmware) is the VMOD that has the mmio ranges. Get that.
1257 for (ancestor = device->parent; ancestor; ancestor = ancestor->parent) {
1258 result = acpi_walk_resources(ancestor->handle, METHOD_NAME__CRS,
1259 vmbus_walk_resources, NULL);
1261 if (ACPI_FAILURE(result))
1269 complete(&probe_event);
1271 vmbus_acpi_remove(device);
1275 static const struct acpi_device_id vmbus_acpi_device_ids[] = {
1280 MODULE_DEVICE_TABLE(acpi, vmbus_acpi_device_ids);
1282 static struct acpi_driver vmbus_acpi_driver = {
1284 .ids = vmbus_acpi_device_ids,
1286 .add = vmbus_acpi_add,
1287 .remove = vmbus_acpi_remove,
1291 static void hv_kexec_handler(void)
1295 hv_synic_clockevents_cleanup();
1296 vmbus_initiate_unload();
1297 for_each_online_cpu(cpu)
1298 smp_call_function_single(cpu, hv_synic_cleanup, NULL, 1);
1302 static void hv_crash_handler(struct pt_regs *regs)
1304 vmbus_initiate_unload();
1306 * In crash handler we can't schedule synic cleanup for all CPUs,
1307 * doing the cleanup for current CPU only. This should be sufficient
1310 hv_synic_cleanup(NULL);
1314 static int __init hv_acpi_init(void)
1318 if (x86_hyper != &x86_hyper_ms_hyperv)
1321 init_completion(&probe_event);
1324 * Get ACPI resources first.
1326 ret = acpi_bus_register_driver(&vmbus_acpi_driver);
1331 t = wait_for_completion_timeout(&probe_event, 5*HZ);
1337 ret = vmbus_bus_init();
1341 hv_setup_kexec_handler(hv_kexec_handler);
1342 hv_setup_crash_handler(hv_crash_handler);
1347 acpi_bus_unregister_driver(&vmbus_acpi_driver);
1352 static void __exit vmbus_exit(void)
1356 hv_remove_kexec_handler();
1357 hv_remove_crash_handler();
1358 vmbus_connection.conn_state = DISCONNECTED;
1359 hv_synic_clockevents_cleanup();
1361 hv_remove_vmbus_irq();
1362 tasklet_kill(&msg_dpc);
1363 vmbus_free_channels();
1364 if (ms_hyperv.misc_features & HV_FEATURE_GUEST_CRASH_MSR_AVAILABLE) {
1365 unregister_die_notifier(&hyperv_die_block);
1366 atomic_notifier_chain_unregister(&panic_notifier_list,
1367 &hyperv_panic_block);
1369 bus_unregister(&hv_bus);
1371 for_each_online_cpu(cpu) {
1372 tasklet_kill(hv_context.event_dpc[cpu]);
1373 smp_call_function_single(cpu, hv_synic_cleanup, NULL, 1);
1376 acpi_bus_unregister_driver(&vmbus_acpi_driver);
1377 if (vmbus_proto_version > VERSION_WIN7)
1378 cpu_hotplug_enable();
1382 MODULE_LICENSE("GPL");
1384 subsys_initcall(hv_acpi_init);
1385 module_exit(vmbus_exit);