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>
21 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
23 #include <linux/kernel.h>
24 #include <linux/sched.h>
25 #include <linux/wait.h>
27 #include <linux/slab.h>
28 #include <linux/list.h>
29 #include <linux/module.h>
30 #include <linux/completion.h>
31 #include <linux/hyperv.h>
33 #include "hyperv_vmbus.h"
35 static void init_vp_index(struct vmbus_channel
*channel
,
36 const uuid_le
*type_guid
);
39 * vmbus_prep_negotiate_resp() - Create default response for Hyper-V Negotiate message
40 * @icmsghdrp: Pointer to msg header structure
41 * @icmsg_negotiate: Pointer to negotiate message structure
42 * @buf: Raw buffer channel data
44 * @icmsghdrp is of type &struct icmsg_hdr.
45 * @negop is of type &struct icmsg_negotiate.
46 * Set up and fill in default negotiate response message.
48 * The fw_version specifies the framework version that
49 * we can support and srv_version specifies the service
50 * version we can support.
52 * Mainly used by Hyper-V drivers.
54 bool vmbus_prep_negotiate_resp(struct icmsg_hdr
*icmsghdrp
,
55 struct icmsg_negotiate
*negop
, u8
*buf
,
56 int fw_version
, int srv_version
)
58 int icframe_major
, icframe_minor
;
59 int icmsg_major
, icmsg_minor
;
60 int fw_major
, fw_minor
;
61 int srv_major
, srv_minor
;
63 bool found_match
= false;
65 icmsghdrp
->icmsgsize
= 0x10;
66 fw_major
= (fw_version
>> 16);
67 fw_minor
= (fw_version
& 0xFFFF);
69 srv_major
= (srv_version
>> 16);
70 srv_minor
= (srv_version
& 0xFFFF);
72 negop
= (struct icmsg_negotiate
*)&buf
[
73 sizeof(struct vmbuspipe_hdr
) +
74 sizeof(struct icmsg_hdr
)];
76 icframe_major
= negop
->icframe_vercnt
;
79 icmsg_major
= negop
->icmsg_vercnt
;
83 * Select the framework version number we will
87 for (i
= 0; i
< negop
->icframe_vercnt
; i
++) {
88 if ((negop
->icversion_data
[i
].major
== fw_major
) &&
89 (negop
->icversion_data
[i
].minor
== fw_minor
)) {
90 icframe_major
= negop
->icversion_data
[i
].major
;
91 icframe_minor
= negop
->icversion_data
[i
].minor
;
101 for (i
= negop
->icframe_vercnt
;
102 (i
< negop
->icframe_vercnt
+ negop
->icmsg_vercnt
); i
++) {
103 if ((negop
->icversion_data
[i
].major
== srv_major
) &&
104 (negop
->icversion_data
[i
].minor
== srv_minor
)) {
105 icmsg_major
= negop
->icversion_data
[i
].major
;
106 icmsg_minor
= negop
->icversion_data
[i
].minor
;
112 * Respond with the framework and service
113 * version numbers we can support.
118 negop
->icframe_vercnt
= 0;
119 negop
->icmsg_vercnt
= 0;
121 negop
->icframe_vercnt
= 1;
122 negop
->icmsg_vercnt
= 1;
125 negop
->icversion_data
[0].major
= icframe_major
;
126 negop
->icversion_data
[0].minor
= icframe_minor
;
127 negop
->icversion_data
[1].major
= icmsg_major
;
128 negop
->icversion_data
[1].minor
= icmsg_minor
;
132 EXPORT_SYMBOL_GPL(vmbus_prep_negotiate_resp
);
135 * alloc_channel - Allocate and initialize a vmbus channel object
137 static struct vmbus_channel
*alloc_channel(void)
139 static atomic_t chan_num
= ATOMIC_INIT(0);
140 struct vmbus_channel
*channel
;
142 channel
= kzalloc(sizeof(*channel
), GFP_ATOMIC
);
146 channel
->id
= atomic_inc_return(&chan_num
);
147 spin_lock_init(&channel
->inbound_lock
);
148 spin_lock_init(&channel
->lock
);
150 INIT_LIST_HEAD(&channel
->sc_list
);
151 INIT_LIST_HEAD(&channel
->percpu_list
);
157 * free_channel - Release the resources used by the vmbus channel object
159 static void free_channel(struct vmbus_channel
*channel
)
164 static void percpu_channel_enq(void *arg
)
166 struct vmbus_channel
*channel
= arg
;
167 int cpu
= smp_processor_id();
169 list_add_tail(&channel
->percpu_list
, &hv_context
.percpu_list
[cpu
]);
172 static void percpu_channel_deq(void *arg
)
174 struct vmbus_channel
*channel
= arg
;
176 list_del(&channel
->percpu_list
);
180 static void vmbus_release_relid(u32 relid
)
182 struct vmbus_channel_relid_released msg
;
184 memset(&msg
, 0, sizeof(struct vmbus_channel_relid_released
));
185 msg
.child_relid
= relid
;
186 msg
.header
.msgtype
= CHANNELMSG_RELID_RELEASED
;
187 vmbus_post_msg(&msg
, sizeof(struct vmbus_channel_relid_released
));
190 void hv_process_channel_removal(struct vmbus_channel
*channel
, u32 relid
)
193 struct vmbus_channel
*primary_channel
;
195 vmbus_release_relid(relid
);
197 BUG_ON(!channel
->rescind
);
199 if (channel
->target_cpu
!= get_cpu()) {
201 smp_call_function_single(channel
->target_cpu
,
202 percpu_channel_deq
, channel
, true);
204 percpu_channel_deq(channel
);
208 if (channel
->primary_channel
== NULL
) {
209 mutex_lock(&vmbus_connection
.channel_mutex
);
210 list_del(&channel
->listentry
);
211 mutex_unlock(&vmbus_connection
.channel_mutex
);
213 primary_channel
= channel
;
215 primary_channel
= channel
->primary_channel
;
216 spin_lock_irqsave(&primary_channel
->lock
, flags
);
217 list_del(&channel
->sc_list
);
218 primary_channel
->num_sc
--;
219 spin_unlock_irqrestore(&primary_channel
->lock
, flags
);
223 * We need to free the bit for init_vp_index() to work in the case
224 * of sub-channel, when we reload drivers like hv_netvsc.
226 cpumask_clear_cpu(channel
->target_cpu
,
227 &primary_channel
->alloced_cpus_in_node
);
229 free_channel(channel
);
232 void vmbus_free_channels(void)
234 struct vmbus_channel
*channel
, *tmp
;
236 list_for_each_entry_safe(channel
, tmp
, &vmbus_connection
.chn_list
,
238 /* hv_process_channel_removal() needs this */
239 channel
->rescind
= true;
241 vmbus_device_unregister(channel
->device_obj
);
246 * vmbus_process_offer - Process the offer by creating a channel/device
247 * associated with this offer
249 static void vmbus_process_offer(struct vmbus_channel
*newchannel
)
251 struct vmbus_channel
*channel
;
255 /* Make sure this is a new offer */
256 mutex_lock(&vmbus_connection
.channel_mutex
);
258 list_for_each_entry(channel
, &vmbus_connection
.chn_list
, listentry
) {
259 if (!uuid_le_cmp(channel
->offermsg
.offer
.if_type
,
260 newchannel
->offermsg
.offer
.if_type
) &&
261 !uuid_le_cmp(channel
->offermsg
.offer
.if_instance
,
262 newchannel
->offermsg
.offer
.if_instance
)) {
269 list_add_tail(&newchannel
->listentry
,
270 &vmbus_connection
.chn_list
);
272 mutex_unlock(&vmbus_connection
.channel_mutex
);
276 * Check to see if this is a sub-channel.
278 if (newchannel
->offermsg
.offer
.sub_channel_index
!= 0) {
280 * Process the sub-channel.
282 newchannel
->primary_channel
= channel
;
283 spin_lock_irqsave(&channel
->lock
, flags
);
284 list_add_tail(&newchannel
->sc_list
, &channel
->sc_list
);
286 spin_unlock_irqrestore(&channel
->lock
, flags
);
291 init_vp_index(newchannel
, &newchannel
->offermsg
.offer
.if_type
);
293 if (newchannel
->target_cpu
!= get_cpu()) {
295 smp_call_function_single(newchannel
->target_cpu
,
299 percpu_channel_enq(newchannel
);
304 * This state is used to indicate a successful open
305 * so that when we do close the channel normally, we
306 * can cleanup properly
308 newchannel
->state
= CHANNEL_OPEN_STATE
;
311 if (channel
->sc_creation_callback
!= NULL
)
312 channel
->sc_creation_callback(newchannel
);
317 * Start the process of binding this offer to the driver
318 * We need to set the DeviceObject field before calling
319 * vmbus_child_dev_add()
321 newchannel
->device_obj
= vmbus_device_create(
322 &newchannel
->offermsg
.offer
.if_type
,
323 &newchannel
->offermsg
.offer
.if_instance
,
325 if (!newchannel
->device_obj
)
329 * Add the new device to the bus. This will kick off device-driver
330 * binding which eventually invokes the device driver's AddDevice()
333 if (vmbus_device_register(newchannel
->device_obj
) != 0) {
334 pr_err("unable to add child device object (relid %d)\n",
335 newchannel
->offermsg
.child_relid
);
336 kfree(newchannel
->device_obj
);
342 vmbus_release_relid(newchannel
->offermsg
.child_relid
);
344 mutex_lock(&vmbus_connection
.channel_mutex
);
345 list_del(&newchannel
->listentry
);
346 mutex_unlock(&vmbus_connection
.channel_mutex
);
348 if (newchannel
->target_cpu
!= get_cpu()) {
350 smp_call_function_single(newchannel
->target_cpu
,
351 percpu_channel_deq
, newchannel
, true);
353 percpu_channel_deq(newchannel
);
358 free_channel(newchannel
);
372 * This is an array of device_ids (device types) that are performance critical.
373 * We attempt to distribute the interrupt load for these devices across
374 * all available CPUs.
376 static const struct hv_vmbus_device_id hp_devs
[] = {
382 { HV_SYNTHFC_GUID
, },
385 /* NetworkDirect Guest RDMA */
387 /* PCI Express Pass Through */
393 * We use this state to statically distribute the channel interrupt load.
395 static int next_numa_node_id
;
398 * Starting with Win8, we can statically distribute the incoming
399 * channel interrupt load by binding a channel to VCPU.
400 * We do this in a hierarchical fashion:
401 * First distribute the primary channels across available NUMA nodes
402 * and then distribute the subchannels amongst the CPUs in the NUMA
403 * node assigned to the primary channel.
405 * For pre-win8 hosts or non-performance critical channels we assign the
406 * first CPU in the first NUMA node.
408 static void init_vp_index(struct vmbus_channel
*channel
, const uuid_le
*type_guid
)
412 bool perf_chn
= false;
413 struct vmbus_channel
*primary
= channel
->primary_channel
;
415 struct cpumask available_mask
;
416 struct cpumask
*alloced_mask
;
418 for (i
= IDE
; i
< MAX_PERF_CHN
; i
++) {
419 if (!uuid_le_cmp(*type_guid
, hp_devs
[i
].guid
)) {
424 if ((vmbus_proto_version
== VERSION_WS2008
) ||
425 (vmbus_proto_version
== VERSION_WIN7
) || (!perf_chn
)) {
427 * Prior to win8, all channel interrupts are
428 * delivered on cpu 0.
429 * Also if the channel is not a performance critical
430 * channel, bind it to cpu 0.
432 channel
->numa_node
= 0;
433 channel
->target_cpu
= 0;
434 channel
->target_vp
= hv_context
.vp_index
[0];
439 * We distribute primary channels evenly across all the available
440 * NUMA nodes and within the assigned NUMA node we will assign the
441 * first available CPU to the primary channel.
442 * The sub-channels will be assigned to the CPUs available in the
447 next_node
= next_numa_node_id
++;
448 if (next_node
== nr_node_ids
)
449 next_node
= next_numa_node_id
= 0;
450 if (cpumask_empty(cpumask_of_node(next_node
)))
454 channel
->numa_node
= next_node
;
457 alloced_mask
= &hv_context
.hv_numa_map
[primary
->numa_node
];
459 if (cpumask_weight(alloced_mask
) ==
460 cpumask_weight(cpumask_of_node(primary
->numa_node
))) {
462 * We have cycled through all the CPUs in the node;
463 * reset the alloced map.
465 cpumask_clear(alloced_mask
);
468 cpumask_xor(&available_mask
, alloced_mask
,
469 cpumask_of_node(primary
->numa_node
));
473 cur_cpu
= cpumask_next(cur_cpu
, &available_mask
);
474 if (cur_cpu
>= nr_cpu_ids
) {
476 cpumask_copy(&available_mask
,
477 cpumask_of_node(primary
->numa_node
));
482 * NOTE: in the case of sub-channel, we clear the sub-channel
483 * related bit(s) in primary->alloced_cpus_in_node in
484 * hv_process_channel_removal(), so when we reload drivers
485 * like hv_netvsc in SMP guest, here we're able to re-allocate
486 * bit from primary->alloced_cpus_in_node.
488 if (!cpumask_test_cpu(cur_cpu
,
489 &primary
->alloced_cpus_in_node
)) {
490 cpumask_set_cpu(cur_cpu
,
491 &primary
->alloced_cpus_in_node
);
492 cpumask_set_cpu(cur_cpu
, alloced_mask
);
497 channel
->target_cpu
= cur_cpu
;
498 channel
->target_vp
= hv_context
.vp_index
[cur_cpu
];
502 * vmbus_unload_response - Handler for the unload response.
504 static void vmbus_unload_response(struct vmbus_channel_message_header
*hdr
)
507 * This is a global event; just wakeup the waiting thread.
508 * Once we successfully unload, we can cleanup the monitor state.
510 complete(&vmbus_connection
.unload_event
);
513 void vmbus_initiate_unload(void)
515 struct vmbus_channel_message_header hdr
;
517 /* Pre-Win2012R2 hosts don't support reconnect */
518 if (vmbus_proto_version
< VERSION_WIN8_1
)
521 init_completion(&vmbus_connection
.unload_event
);
522 memset(&hdr
, 0, sizeof(struct vmbus_channel_message_header
));
523 hdr
.msgtype
= CHANNELMSG_UNLOAD
;
524 vmbus_post_msg(&hdr
, sizeof(struct vmbus_channel_message_header
));
526 wait_for_completion(&vmbus_connection
.unload_event
);
530 * vmbus_onoffer - Handler for channel offers from vmbus in parent partition.
533 static void vmbus_onoffer(struct vmbus_channel_message_header
*hdr
)
535 struct vmbus_channel_offer_channel
*offer
;
536 struct vmbus_channel
*newchannel
;
538 offer
= (struct vmbus_channel_offer_channel
*)hdr
;
540 /* Allocate the channel object and save this offer. */
541 newchannel
= alloc_channel();
543 pr_err("Unable to allocate channel object\n");
548 * By default we setup state to enable batched
549 * reading. A specific service can choose to
550 * disable this prior to opening the channel.
552 newchannel
->batched_reading
= true;
555 * Setup state for signalling the host.
557 newchannel
->sig_event
= (struct hv_input_signal_event
*)
558 (ALIGN((unsigned long)
559 &newchannel
->sig_buf
,
560 HV_HYPERCALL_PARAM_ALIGN
));
562 newchannel
->sig_event
->connectionid
.asu32
= 0;
563 newchannel
->sig_event
->connectionid
.u
.id
= VMBUS_EVENT_CONNECTION_ID
;
564 newchannel
->sig_event
->flag_number
= 0;
565 newchannel
->sig_event
->rsvdz
= 0;
567 if (vmbus_proto_version
!= VERSION_WS2008
) {
568 newchannel
->is_dedicated_interrupt
=
569 (offer
->is_dedicated_interrupt
!= 0);
570 newchannel
->sig_event
->connectionid
.u
.id
=
571 offer
->connection_id
;
574 memcpy(&newchannel
->offermsg
, offer
,
575 sizeof(struct vmbus_channel_offer_channel
));
576 newchannel
->monitor_grp
= (u8
)offer
->monitorid
/ 32;
577 newchannel
->monitor_bit
= (u8
)offer
->monitorid
% 32;
579 vmbus_process_offer(newchannel
);
583 * vmbus_onoffer_rescind - Rescind offer handler.
585 * We queue a work item to process this offer synchronously
587 static void vmbus_onoffer_rescind(struct vmbus_channel_message_header
*hdr
)
589 struct vmbus_channel_rescind_offer
*rescind
;
590 struct vmbus_channel
*channel
;
594 rescind
= (struct vmbus_channel_rescind_offer
*)hdr
;
595 channel
= relid2channel(rescind
->child_relid
);
597 if (channel
== NULL
) {
599 * This is very impossible, because in
600 * vmbus_process_offer(), we have already invoked
601 * vmbus_release_relid() on error.
606 spin_lock_irqsave(&channel
->lock
, flags
);
607 channel
->rescind
= true;
608 spin_unlock_irqrestore(&channel
->lock
, flags
);
610 if (channel
->device_obj
) {
612 * We will have to unregister this device from the
615 dev
= get_device(&channel
->device_obj
->device
);
617 vmbus_device_unregister(channel
->device_obj
);
621 hv_process_channel_removal(channel
,
622 channel
->offermsg
.child_relid
);
627 * vmbus_onoffers_delivered -
628 * This is invoked when all offers have been delivered.
630 * Nothing to do here.
632 static void vmbus_onoffers_delivered(
633 struct vmbus_channel_message_header
*hdr
)
638 * vmbus_onopen_result - Open result handler.
640 * This is invoked when we received a response to our channel open request.
641 * Find the matching request, copy the response and signal the requesting
644 static void vmbus_onopen_result(struct vmbus_channel_message_header
*hdr
)
646 struct vmbus_channel_open_result
*result
;
647 struct vmbus_channel_msginfo
*msginfo
;
648 struct vmbus_channel_message_header
*requestheader
;
649 struct vmbus_channel_open_channel
*openmsg
;
652 result
= (struct vmbus_channel_open_result
*)hdr
;
655 * Find the open msg, copy the result and signal/unblock the wait event
657 spin_lock_irqsave(&vmbus_connection
.channelmsg_lock
, flags
);
659 list_for_each_entry(msginfo
, &vmbus_connection
.chn_msg_list
,
662 (struct vmbus_channel_message_header
*)msginfo
->msg
;
664 if (requestheader
->msgtype
== CHANNELMSG_OPENCHANNEL
) {
666 (struct vmbus_channel_open_channel
*)msginfo
->msg
;
667 if (openmsg
->child_relid
== result
->child_relid
&&
668 openmsg
->openid
== result
->openid
) {
669 memcpy(&msginfo
->response
.open_result
,
672 struct vmbus_channel_open_result
));
673 complete(&msginfo
->waitevent
);
678 spin_unlock_irqrestore(&vmbus_connection
.channelmsg_lock
, flags
);
682 * vmbus_ongpadl_created - GPADL created handler.
684 * This is invoked when we received a response to our gpadl create request.
685 * Find the matching request, copy the response and signal the requesting
688 static void vmbus_ongpadl_created(struct vmbus_channel_message_header
*hdr
)
690 struct vmbus_channel_gpadl_created
*gpadlcreated
;
691 struct vmbus_channel_msginfo
*msginfo
;
692 struct vmbus_channel_message_header
*requestheader
;
693 struct vmbus_channel_gpadl_header
*gpadlheader
;
696 gpadlcreated
= (struct vmbus_channel_gpadl_created
*)hdr
;
699 * Find the establish msg, copy the result and signal/unblock the wait
702 spin_lock_irqsave(&vmbus_connection
.channelmsg_lock
, flags
);
704 list_for_each_entry(msginfo
, &vmbus_connection
.chn_msg_list
,
707 (struct vmbus_channel_message_header
*)msginfo
->msg
;
709 if (requestheader
->msgtype
== CHANNELMSG_GPADL_HEADER
) {
711 (struct vmbus_channel_gpadl_header
*)requestheader
;
713 if ((gpadlcreated
->child_relid
==
714 gpadlheader
->child_relid
) &&
715 (gpadlcreated
->gpadl
== gpadlheader
->gpadl
)) {
716 memcpy(&msginfo
->response
.gpadl_created
,
719 struct vmbus_channel_gpadl_created
));
720 complete(&msginfo
->waitevent
);
725 spin_unlock_irqrestore(&vmbus_connection
.channelmsg_lock
, flags
);
729 * vmbus_ongpadl_torndown - GPADL torndown handler.
731 * This is invoked when we received a response to our gpadl teardown request.
732 * Find the matching request, copy the response and signal the requesting
735 static void vmbus_ongpadl_torndown(
736 struct vmbus_channel_message_header
*hdr
)
738 struct vmbus_channel_gpadl_torndown
*gpadl_torndown
;
739 struct vmbus_channel_msginfo
*msginfo
;
740 struct vmbus_channel_message_header
*requestheader
;
741 struct vmbus_channel_gpadl_teardown
*gpadl_teardown
;
744 gpadl_torndown
= (struct vmbus_channel_gpadl_torndown
*)hdr
;
747 * Find the open msg, copy the result and signal/unblock the wait event
749 spin_lock_irqsave(&vmbus_connection
.channelmsg_lock
, flags
);
751 list_for_each_entry(msginfo
, &vmbus_connection
.chn_msg_list
,
754 (struct vmbus_channel_message_header
*)msginfo
->msg
;
756 if (requestheader
->msgtype
== CHANNELMSG_GPADL_TEARDOWN
) {
758 (struct vmbus_channel_gpadl_teardown
*)requestheader
;
760 if (gpadl_torndown
->gpadl
== gpadl_teardown
->gpadl
) {
761 memcpy(&msginfo
->response
.gpadl_torndown
,
764 struct vmbus_channel_gpadl_torndown
));
765 complete(&msginfo
->waitevent
);
770 spin_unlock_irqrestore(&vmbus_connection
.channelmsg_lock
, flags
);
774 * vmbus_onversion_response - Version response handler
776 * This is invoked when we received a response to our initiate contact request.
777 * Find the matching request, copy the response and signal the requesting
780 static void vmbus_onversion_response(
781 struct vmbus_channel_message_header
*hdr
)
783 struct vmbus_channel_msginfo
*msginfo
;
784 struct vmbus_channel_message_header
*requestheader
;
785 struct vmbus_channel_version_response
*version_response
;
788 version_response
= (struct vmbus_channel_version_response
*)hdr
;
789 spin_lock_irqsave(&vmbus_connection
.channelmsg_lock
, flags
);
791 list_for_each_entry(msginfo
, &vmbus_connection
.chn_msg_list
,
794 (struct vmbus_channel_message_header
*)msginfo
->msg
;
796 if (requestheader
->msgtype
==
797 CHANNELMSG_INITIATE_CONTACT
) {
798 memcpy(&msginfo
->response
.version_response
,
800 sizeof(struct vmbus_channel_version_response
));
801 complete(&msginfo
->waitevent
);
804 spin_unlock_irqrestore(&vmbus_connection
.channelmsg_lock
, flags
);
807 /* Channel message dispatch table */
808 struct vmbus_channel_message_table_entry
809 channel_message_table
[CHANNELMSG_COUNT
] = {
810 {CHANNELMSG_INVALID
, 0, NULL
},
811 {CHANNELMSG_OFFERCHANNEL
, 0, vmbus_onoffer
},
812 {CHANNELMSG_RESCIND_CHANNELOFFER
, 0, vmbus_onoffer_rescind
},
813 {CHANNELMSG_REQUESTOFFERS
, 0, NULL
},
814 {CHANNELMSG_ALLOFFERS_DELIVERED
, 1, vmbus_onoffers_delivered
},
815 {CHANNELMSG_OPENCHANNEL
, 0, NULL
},
816 {CHANNELMSG_OPENCHANNEL_RESULT
, 1, vmbus_onopen_result
},
817 {CHANNELMSG_CLOSECHANNEL
, 0, NULL
},
818 {CHANNELMSG_GPADL_HEADER
, 0, NULL
},
819 {CHANNELMSG_GPADL_BODY
, 0, NULL
},
820 {CHANNELMSG_GPADL_CREATED
, 1, vmbus_ongpadl_created
},
821 {CHANNELMSG_GPADL_TEARDOWN
, 0, NULL
},
822 {CHANNELMSG_GPADL_TORNDOWN
, 1, vmbus_ongpadl_torndown
},
823 {CHANNELMSG_RELID_RELEASED
, 0, NULL
},
824 {CHANNELMSG_INITIATE_CONTACT
, 0, NULL
},
825 {CHANNELMSG_VERSION_RESPONSE
, 1, vmbus_onversion_response
},
826 {CHANNELMSG_UNLOAD
, 0, NULL
},
827 {CHANNELMSG_UNLOAD_RESPONSE
, 1, vmbus_unload_response
},
831 * vmbus_onmessage - Handler for channel protocol messages.
833 * This is invoked in the vmbus worker thread context.
835 void vmbus_onmessage(void *context
)
837 struct hv_message
*msg
= context
;
838 struct vmbus_channel_message_header
*hdr
;
841 hdr
= (struct vmbus_channel_message_header
*)msg
->u
.payload
;
842 size
= msg
->header
.payload_size
;
844 if (hdr
->msgtype
>= CHANNELMSG_COUNT
) {
845 pr_err("Received invalid channel message type %d size %d\n",
847 print_hex_dump_bytes("", DUMP_PREFIX_NONE
,
848 (unsigned char *)msg
->u
.payload
, size
);
852 if (channel_message_table
[hdr
->msgtype
].message_handler
)
853 channel_message_table
[hdr
->msgtype
].message_handler(hdr
);
855 pr_err("Unhandled channel message type %d\n", hdr
->msgtype
);
859 * vmbus_request_offers - Send a request to get all our pending offers.
861 int vmbus_request_offers(void)
863 struct vmbus_channel_message_header
*msg
;
864 struct vmbus_channel_msginfo
*msginfo
;
867 msginfo
= kmalloc(sizeof(*msginfo
) +
868 sizeof(struct vmbus_channel_message_header
),
873 msg
= (struct vmbus_channel_message_header
*)msginfo
->msg
;
875 msg
->msgtype
= CHANNELMSG_REQUESTOFFERS
;
878 ret
= vmbus_post_msg(msg
,
879 sizeof(struct vmbus_channel_message_header
));
881 pr_err("Unable to request offers - %d\n", ret
);
893 * Retrieve the (sub) channel on which to send an outgoing request.
894 * When a primary channel has multiple sub-channels, we try to
895 * distribute the load equally amongst all available channels.
897 struct vmbus_channel
*vmbus_get_outgoing_channel(struct vmbus_channel
*primary
)
899 struct list_head
*cur
, *tmp
;
901 struct vmbus_channel
*cur_channel
;
902 struct vmbus_channel
*outgoing_channel
= primary
;
906 if (list_empty(&primary
->sc_list
))
907 return outgoing_channel
;
909 next_channel
= primary
->next_oc
++;
911 if (next_channel
> (primary
->num_sc
)) {
912 primary
->next_oc
= 0;
913 return outgoing_channel
;
916 cur_cpu
= hv_context
.vp_index
[get_cpu()];
918 list_for_each_safe(cur
, tmp
, &primary
->sc_list
) {
919 cur_channel
= list_entry(cur
, struct vmbus_channel
, sc_list
);
920 if (cur_channel
->state
!= CHANNEL_OPENED_STATE
)
923 if (cur_channel
->target_vp
== cur_cpu
)
926 if (i
== next_channel
)
932 return outgoing_channel
;
934 EXPORT_SYMBOL_GPL(vmbus_get_outgoing_channel
);
936 static void invoke_sc_cb(struct vmbus_channel
*primary_channel
)
938 struct list_head
*cur
, *tmp
;
939 struct vmbus_channel
*cur_channel
;
941 if (primary_channel
->sc_creation_callback
== NULL
)
944 list_for_each_safe(cur
, tmp
, &primary_channel
->sc_list
) {
945 cur_channel
= list_entry(cur
, struct vmbus_channel
, sc_list
);
947 primary_channel
->sc_creation_callback(cur_channel
);
951 void vmbus_set_sc_create_callback(struct vmbus_channel
*primary_channel
,
952 void (*sc_cr_cb
)(struct vmbus_channel
*new_sc
))
954 primary_channel
->sc_creation_callback
= sc_cr_cb
;
956 EXPORT_SYMBOL_GPL(vmbus_set_sc_create_callback
);
958 bool vmbus_are_subchannels_present(struct vmbus_channel
*primary
)
962 ret
= !list_empty(&primary
->sc_list
);
966 * Invoke the callback on sub-channel creation.
967 * This will present a uniform interface to the
970 invoke_sc_cb(primary
);
975 EXPORT_SYMBOL_GPL(vmbus_are_subchannels_present
);