Commit | Line | Data |
---|---|---|
3e7ee490 | 1 | /* |
3e7ee490 HJ |
2 | * Copyright (c) 2009, Microsoft Corporation. |
3 | * | |
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. | |
7 | * | |
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 | |
11 | * more details. | |
12 | * | |
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. | |
16 | * | |
17 | * Authors: | |
18 | * Haiyang Zhang <haiyangz@microsoft.com> | |
19 | * Hank Janssen <hjanssen@microsoft.com> | |
3e7ee490 | 20 | */ |
0a46618d HJ |
21 | #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt |
22 | ||
a0086dc5 | 23 | #include <linux/kernel.h> |
0c3b7b2f S |
24 | #include <linux/sched.h> |
25 | #include <linux/wait.h> | |
a0086dc5 | 26 | #include <linux/mm.h> |
5a0e3ad6 | 27 | #include <linux/slab.h> |
53af545b | 28 | #include <linux/list.h> |
c88c4e4c | 29 | #include <linux/module.h> |
8b5d6d3b | 30 | #include <linux/completion.h> |
46a97191 | 31 | #include <linux/hyperv.h> |
3f335ea2 | 32 | |
0f2a6619 | 33 | #include "hyperv_vmbus.h" |
3e7ee490 | 34 | |
f38e7dd7 VK |
35 | static void init_vp_index(struct vmbus_channel *channel, |
36 | const uuid_le *type_guid); | |
37 | ||
c88c4e4c | 38 | /** |
da0e9631 | 39 | * vmbus_prep_negotiate_resp() - Create default response for Hyper-V Negotiate message |
c88c4e4c HJ |
40 | * @icmsghdrp: Pointer to msg header structure |
41 | * @icmsg_negotiate: Pointer to negotiate message structure | |
42 | * @buf: Raw buffer channel data | |
43 | * | |
44 | * @icmsghdrp is of type &struct icmsg_hdr. | |
45 | * @negop is of type &struct icmsg_negotiate. | |
c836d0ab S |
46 | * Set up and fill in default negotiate response message. |
47 | * | |
6741335b S |
48 | * The fw_version specifies the framework version that |
49 | * we can support and srv_version specifies the service | |
50 | * version we can support. | |
c88c4e4c HJ |
51 | * |
52 | * Mainly used by Hyper-V drivers. | |
53 | */ | |
6741335b | 54 | bool vmbus_prep_negotiate_resp(struct icmsg_hdr *icmsghdrp, |
c836d0ab | 55 | struct icmsg_negotiate *negop, u8 *buf, |
6741335b | 56 | int fw_version, int srv_version) |
c88c4e4c | 57 | { |
6741335b S |
58 | int icframe_major, icframe_minor; |
59 | int icmsg_major, icmsg_minor; | |
60 | int fw_major, fw_minor; | |
61 | int srv_major, srv_minor; | |
c836d0ab | 62 | int i; |
6741335b | 63 | bool found_match = false; |
c836d0ab | 64 | |
a3605300 | 65 | icmsghdrp->icmsgsize = 0x10; |
6741335b S |
66 | fw_major = (fw_version >> 16); |
67 | fw_minor = (fw_version & 0xFFFF); | |
68 | ||
69 | srv_major = (srv_version >> 16); | |
70 | srv_minor = (srv_version & 0xFFFF); | |
c88c4e4c | 71 | |
a3605300 S |
72 | negop = (struct icmsg_negotiate *)&buf[ |
73 | sizeof(struct vmbuspipe_hdr) + | |
74 | sizeof(struct icmsg_hdr)]; | |
c88c4e4c | 75 | |
6741335b S |
76 | icframe_major = negop->icframe_vercnt; |
77 | icframe_minor = 0; | |
78 | ||
79 | icmsg_major = negop->icmsg_vercnt; | |
80 | icmsg_minor = 0; | |
c836d0ab S |
81 | |
82 | /* | |
83 | * Select the framework version number we will | |
84 | * support. | |
85 | */ | |
86 | ||
87 | for (i = 0; i < negop->icframe_vercnt; i++) { | |
6741335b S |
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; | |
92 | found_match = true; | |
93 | } | |
c836d0ab S |
94 | } |
95 | ||
6741335b S |
96 | if (!found_match) |
97 | goto fw_error; | |
98 | ||
99 | found_match = false; | |
100 | ||
c836d0ab S |
101 | for (i = negop->icframe_vercnt; |
102 | (i < negop->icframe_vercnt + negop->icmsg_vercnt); i++) { | |
6741335b S |
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; | |
107 | found_match = true; | |
108 | } | |
c88c4e4c | 109 | } |
a3605300 | 110 | |
c836d0ab | 111 | /* |
6741335b | 112 | * Respond with the framework and service |
c836d0ab S |
113 | * version numbers we can support. |
114 | */ | |
6741335b S |
115 | |
116 | fw_error: | |
117 | if (!found_match) { | |
118 | negop->icframe_vercnt = 0; | |
119 | negop->icmsg_vercnt = 0; | |
120 | } else { | |
121 | negop->icframe_vercnt = 1; | |
122 | negop->icmsg_vercnt = 1; | |
123 | } | |
124 | ||
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; | |
129 | return found_match; | |
c88c4e4c | 130 | } |
a3605300 | 131 | |
da0e9631 | 132 | EXPORT_SYMBOL_GPL(vmbus_prep_negotiate_resp); |
c88c4e4c | 133 | |
3e189519 | 134 | /* |
e98cb276 | 135 | * alloc_channel - Allocate and initialize a vmbus channel object |
bd60c33e | 136 | */ |
50fe56d2 | 137 | static struct vmbus_channel *alloc_channel(void) |
3e7ee490 | 138 | { |
bc63b6f6 | 139 | static atomic_t chan_num = ATOMIC_INIT(0); |
aded7165 | 140 | struct vmbus_channel *channel; |
3e7ee490 | 141 | |
aded7165 | 142 | channel = kzalloc(sizeof(*channel), GFP_ATOMIC); |
3e7ee490 | 143 | if (!channel) |
3e7ee490 | 144 | return NULL; |
3e7ee490 | 145 | |
bc63b6f6 | 146 | channel->id = atomic_inc_return(&chan_num); |
54411c42 | 147 | spin_lock_init(&channel->inbound_lock); |
67fae053 | 148 | spin_lock_init(&channel->lock); |
e68d2971 S |
149 | |
150 | INIT_LIST_HEAD(&channel->sc_list); | |
3a28fa35 | 151 | INIT_LIST_HEAD(&channel->percpu_list); |
3e7ee490 | 152 | |
3e7ee490 HJ |
153 | return channel; |
154 | } | |
155 | ||
3e189519 | 156 | /* |
e98cb276 | 157 | * free_channel - Release the resources used by the vmbus channel object |
bd60c33e | 158 | */ |
9f3e28e3 | 159 | static void free_channel(struct vmbus_channel *channel) |
3e7ee490 | 160 | { |
aadc3780 | 161 | kfree(channel); |
3e7ee490 HJ |
162 | } |
163 | ||
3a28fa35 S |
164 | static void percpu_channel_enq(void *arg) |
165 | { | |
166 | struct vmbus_channel *channel = arg; | |
167 | int cpu = smp_processor_id(); | |
168 | ||
169 | list_add_tail(&channel->percpu_list, &hv_context.percpu_list[cpu]); | |
170 | } | |
8b5d6d3b | 171 | |
3a28fa35 S |
172 | static void percpu_channel_deq(void *arg) |
173 | { | |
174 | struct vmbus_channel *channel = arg; | |
175 | ||
176 | list_del(&channel->percpu_list); | |
177 | } | |
8b5d6d3b | 178 | |
ed6cfcc5 | 179 | |
f52078cf | 180 | static void vmbus_release_relid(u32 relid) |
4b2f9abe | 181 | { |
ed6cfcc5 | 182 | struct vmbus_channel_relid_released msg; |
4b2f9abe | 183 | |
c8705979 | 184 | memset(&msg, 0, sizeof(struct vmbus_channel_relid_released)); |
ed6cfcc5 | 185 | msg.child_relid = relid; |
c8705979 S |
186 | msg.header.msgtype = CHANNELMSG_RELID_RELEASED; |
187 | vmbus_post_msg(&msg, sizeof(struct vmbus_channel_relid_released)); | |
f52078cf | 188 | } |
c8705979 | 189 | |
f52078cf DC |
190 | void hv_process_channel_removal(struct vmbus_channel *channel, u32 relid) |
191 | { | |
192 | unsigned long flags; | |
193 | struct vmbus_channel *primary_channel; | |
194 | ||
195 | vmbus_release_relid(relid); | |
ed6cfcc5 | 196 | |
34c6801e DC |
197 | BUG_ON(!channel->rescind); |
198 | ||
2115b561 S |
199 | if (channel->target_cpu != get_cpu()) { |
200 | put_cpu(); | |
3a28fa35 S |
201 | smp_call_function_single(channel->target_cpu, |
202 | percpu_channel_deq, channel, true); | |
2115b561 | 203 | } else { |
3a28fa35 | 204 | percpu_channel_deq(channel); |
2115b561 S |
205 | put_cpu(); |
206 | } | |
3a28fa35 | 207 | |
e68d2971 | 208 | if (channel->primary_channel == NULL) { |
d6f591e3 | 209 | mutex_lock(&vmbus_connection.channel_mutex); |
e68d2971 | 210 | list_del(&channel->listentry); |
d6f591e3 | 211 | mutex_unlock(&vmbus_connection.channel_mutex); |
ca1c4b74 DC |
212 | |
213 | primary_channel = channel; | |
e68d2971 S |
214 | } else { |
215 | primary_channel = channel->primary_channel; | |
67fae053 | 216 | spin_lock_irqsave(&primary_channel->lock, flags); |
565ce642 | 217 | list_del(&channel->sc_list); |
357e836a | 218 | primary_channel->num_sc--; |
67fae053 | 219 | spin_unlock_irqrestore(&primary_channel->lock, flags); |
e68d2971 | 220 | } |
ca1c4b74 DC |
221 | |
222 | /* | |
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. | |
225 | */ | |
226 | cpumask_clear_cpu(channel->target_cpu, | |
227 | &primary_channel->alloced_cpus_in_node); | |
228 | ||
c8705979 | 229 | free_channel(channel); |
4b2f9abe | 230 | } |
8b5d6d3b | 231 | |
93e5bd06 S |
232 | void vmbus_free_channels(void) |
233 | { | |
813c5b79 DC |
234 | struct vmbus_channel *channel, *tmp; |
235 | ||
236 | list_for_each_entry_safe(channel, tmp, &vmbus_connection.chn_list, | |
237 | listentry) { | |
34c6801e | 238 | /* hv_process_channel_removal() needs this */ |
813c5b79 | 239 | channel->rescind = true; |
93e5bd06 | 240 | |
93e5bd06 | 241 | vmbus_device_unregister(channel->device_obj); |
93e5bd06 S |
242 | } |
243 | } | |
244 | ||
3e189519 | 245 | /* |
e98cb276 | 246 | * vmbus_process_offer - Process the offer by creating a channel/device |
c88c4e4c | 247 | * associated with this offer |
bd60c33e | 248 | */ |
2dd37cb8 | 249 | static void vmbus_process_offer(struct vmbus_channel *newchannel) |
3e7ee490 | 250 | { |
aded7165 | 251 | struct vmbus_channel *channel; |
188963ec | 252 | bool fnew = true; |
0f5e44ca | 253 | unsigned long flags; |
3e7ee490 | 254 | |
454f18a9 | 255 | /* Make sure this is a new offer */ |
d6f591e3 | 256 | mutex_lock(&vmbus_connection.channel_mutex); |
3e7ee490 | 257 | |
da9fcb72 | 258 | list_for_each_entry(channel, &vmbus_connection.chn_list, listentry) { |
358d2ee2 S |
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)) { | |
188963ec | 263 | fnew = false; |
3e7ee490 HJ |
264 | break; |
265 | } | |
266 | } | |
267 | ||
8dfd3326 | 268 | if (fnew) |
c50f7fb2 | 269 | list_add_tail(&newchannel->listentry, |
da9fcb72 | 270 | &vmbus_connection.chn_list); |
bd60c33e | 271 | |
d6f591e3 | 272 | mutex_unlock(&vmbus_connection.channel_mutex); |
3e7ee490 | 273 | |
188963ec | 274 | if (!fnew) { |
e68d2971 S |
275 | /* |
276 | * Check to see if this is a sub-channel. | |
277 | */ | |
278 | if (newchannel->offermsg.offer.sub_channel_index != 0) { | |
279 | /* | |
280 | * Process the sub-channel. | |
281 | */ | |
282 | newchannel->primary_channel = channel; | |
67fae053 | 283 | spin_lock_irqsave(&channel->lock, flags); |
e68d2971 | 284 | list_add_tail(&newchannel->sc_list, &channel->sc_list); |
a13e8bbe | 285 | channel->num_sc++; |
357e836a | 286 | spin_unlock_irqrestore(&channel->lock, flags); |
8dfd3326 VK |
287 | } else |
288 | goto err_free_chan; | |
289 | } | |
e68d2971 | 290 | |
f38e7dd7 VK |
291 | init_vp_index(newchannel, &newchannel->offermsg.offer.if_type); |
292 | ||
8dfd3326 VK |
293 | if (newchannel->target_cpu != get_cpu()) { |
294 | put_cpu(); | |
295 | smp_call_function_single(newchannel->target_cpu, | |
296 | percpu_channel_enq, | |
297 | newchannel, true); | |
298 | } else { | |
299 | percpu_channel_enq(newchannel); | |
300 | put_cpu(); | |
3e7ee490 HJ |
301 | } |
302 | ||
42dceebe S |
303 | /* |
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 | |
307 | */ | |
308 | newchannel->state = CHANNEL_OPEN_STATE; | |
309 | ||
8dfd3326 VK |
310 | if (!fnew) { |
311 | if (channel->sc_creation_callback != NULL) | |
312 | channel->sc_creation_callback(newchannel); | |
313 | return; | |
314 | } | |
315 | ||
bd60c33e GKH |
316 | /* |
317 | * Start the process of binding this offer to the driver | |
318 | * We need to set the DeviceObject field before calling | |
646f1ea3 | 319 | * vmbus_child_dev_add() |
bd60c33e | 320 | */ |
f2c73011 | 321 | newchannel->device_obj = vmbus_device_create( |
767dff68 HZ |
322 | &newchannel->offermsg.offer.if_type, |
323 | &newchannel->offermsg.offer.if_instance, | |
188963ec | 324 | newchannel); |
9c3a6f7e | 325 | if (!newchannel->device_obj) |
5b1e5b53 | 326 | goto err_deq_chan; |
3e7ee490 | 327 | |
454f18a9 BP |
328 | /* |
329 | * Add the new device to the bus. This will kick off device-driver | |
330 | * binding which eventually invokes the device driver's AddDevice() | |
331 | * method. | |
332 | */ | |
d43e2fe7 DC |
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); | |
337 | goto err_deq_chan; | |
338 | } | |
9c3a6f7e | 339 | return; |
2dd37cb8 | 340 | |
5b1e5b53 | 341 | err_deq_chan: |
f52078cf DC |
342 | vmbus_release_relid(newchannel->offermsg.child_relid); |
343 | ||
d6f591e3 | 344 | mutex_lock(&vmbus_connection.channel_mutex); |
5b1e5b53 | 345 | list_del(&newchannel->listentry); |
d6f591e3 | 346 | mutex_unlock(&vmbus_connection.channel_mutex); |
5b1e5b53 S |
347 | |
348 | if (newchannel->target_cpu != get_cpu()) { | |
349 | put_cpu(); | |
350 | smp_call_function_single(newchannel->target_cpu, | |
351 | percpu_channel_deq, newchannel, true); | |
352 | } else { | |
353 | percpu_channel_deq(newchannel); | |
354 | put_cpu(); | |
355 | } | |
356 | ||
9c3a6f7e VK |
357 | err_free_chan: |
358 | free_channel(newchannel); | |
3e7ee490 HJ |
359 | } |
360 | ||
a119845f S |
361 | enum { |
362 | IDE = 0, | |
363 | SCSI, | |
879a650a | 364 | FC, |
a119845f | 365 | NIC, |
379e4f75 | 366 | ND_NIC, |
3053c762 | 367 | PCIE, |
a119845f S |
368 | MAX_PERF_CHN, |
369 | }; | |
370 | ||
371 | /* | |
7fb96565 | 372 | * This is an array of device_ids (device types) that are performance critical. |
a119845f S |
373 | * We attempt to distribute the interrupt load for these devices across |
374 | * all available CPUs. | |
375 | */ | |
7fb96565 | 376 | static const struct hv_vmbus_device_id hp_devs[] = { |
a119845f | 377 | /* IDE */ |
7fb96565 | 378 | { HV_IDE_GUID, }, |
a119845f | 379 | /* Storage - SCSI */ |
7fb96565 | 380 | { HV_SCSI_GUID, }, |
879a650a S |
381 | /* Storage - FC */ |
382 | { HV_SYNTHFC_GUID, }, | |
a119845f | 383 | /* Network */ |
7fb96565 | 384 | { HV_NIC_GUID, }, |
04653a00 S |
385 | /* NetworkDirect Guest RDMA */ |
386 | { HV_ND_GUID, }, | |
3053c762 JO |
387 | /* PCI Express Pass Through */ |
388 | { HV_PCIE_GUID, }, | |
a119845f S |
389 | }; |
390 | ||
391 | ||
392 | /* | |
393 | * We use this state to statically distribute the channel interrupt load. | |
394 | */ | |
1f656ff3 | 395 | static int next_numa_node_id; |
a119845f S |
396 | |
397 | /* | |
398 | * Starting with Win8, we can statically distribute the incoming | |
1f656ff3 S |
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. | |
404 | * | |
405 | * For pre-win8 hosts or non-performance critical channels we assign the | |
406 | * first CPU in the first NUMA node. | |
a119845f | 407 | */ |
f9da455b | 408 | static void init_vp_index(struct vmbus_channel *channel, const uuid_le *type_guid) |
a119845f S |
409 | { |
410 | u32 cur_cpu; | |
411 | int i; | |
412 | bool perf_chn = false; | |
1f656ff3 S |
413 | struct vmbus_channel *primary = channel->primary_channel; |
414 | int next_node; | |
415 | struct cpumask available_mask; | |
9f01ec53 | 416 | struct cpumask *alloced_mask; |
a119845f S |
417 | |
418 | for (i = IDE; i < MAX_PERF_CHN; i++) { | |
4ae92508 | 419 | if (!uuid_le_cmp(*type_guid, hp_devs[i].guid)) { |
a119845f S |
420 | perf_chn = true; |
421 | break; | |
422 | } | |
423 | } | |
424 | if ((vmbus_proto_version == VERSION_WS2008) || | |
425 | (vmbus_proto_version == VERSION_WIN7) || (!perf_chn)) { | |
426 | /* | |
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. | |
431 | */ | |
1f656ff3 | 432 | channel->numa_node = 0; |
d3ba720d | 433 | channel->target_cpu = 0; |
9c6e64ad | 434 | channel->target_vp = hv_context.vp_index[0]; |
d3ba720d | 435 | return; |
a119845f | 436 | } |
ce59fec8 VK |
437 | |
438 | /* | |
1f656ff3 S |
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 | |
443 | * NUMA node evenly. | |
ce59fec8 | 444 | */ |
1f656ff3 S |
445 | if (!primary) { |
446 | while (true) { | |
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))) | |
451 | continue; | |
452 | break; | |
453 | } | |
454 | channel->numa_node = next_node; | |
455 | primary = channel; | |
456 | } | |
9f01ec53 | 457 | alloced_mask = &hv_context.hv_numa_map[primary->numa_node]; |
1f656ff3 | 458 | |
9f01ec53 | 459 | if (cpumask_weight(alloced_mask) == |
1f656ff3 | 460 | cpumask_weight(cpumask_of_node(primary->numa_node))) { |
ce59fec8 | 461 | /* |
1f656ff3 S |
462 | * We have cycled through all the CPUs in the node; |
463 | * reset the alloced map. | |
ce59fec8 | 464 | */ |
9f01ec53 | 465 | cpumask_clear(alloced_mask); |
ce59fec8 VK |
466 | } |
467 | ||
9f01ec53 | 468 | cpumask_xor(&available_mask, alloced_mask, |
1f656ff3 S |
469 | cpumask_of_node(primary->numa_node)); |
470 | ||
3b71107d DC |
471 | cur_cpu = -1; |
472 | while (true) { | |
473 | cur_cpu = cpumask_next(cur_cpu, &available_mask); | |
474 | if (cur_cpu >= nr_cpu_ids) { | |
475 | cur_cpu = -1; | |
476 | cpumask_copy(&available_mask, | |
477 | cpumask_of_node(primary->numa_node)); | |
478 | continue; | |
479 | } | |
480 | ||
ca1c4b74 DC |
481 | /* |
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. | |
487 | */ | |
3b71107d DC |
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); | |
493 | break; | |
494 | } | |
495 | } | |
1f656ff3 | 496 | |
d3ba720d S |
497 | channel->target_cpu = cur_cpu; |
498 | channel->target_vp = hv_context.vp_index[cur_cpu]; | |
a119845f S |
499 | } |
500 | ||
2db84eff S |
501 | /* |
502 | * vmbus_unload_response - Handler for the unload response. | |
503 | */ | |
504 | static void vmbus_unload_response(struct vmbus_channel_message_header *hdr) | |
505 | { | |
506 | /* | |
507 | * This is a global event; just wakeup the waiting thread. | |
508 | * Once we successfully unload, we can cleanup the monitor state. | |
509 | */ | |
510 | complete(&vmbus_connection.unload_event); | |
511 | } | |
512 | ||
513 | void vmbus_initiate_unload(void) | |
514 | { | |
515 | struct vmbus_channel_message_header hdr; | |
516 | ||
4a54243f VK |
517 | /* Pre-Win2012R2 hosts don't support reconnect */ |
518 | if (vmbus_proto_version < VERSION_WIN8_1) | |
519 | return; | |
520 | ||
2db84eff S |
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)); | |
525 | ||
526 | wait_for_completion(&vmbus_connection.unload_event); | |
527 | } | |
528 | ||
3e189519 | 529 | /* |
e98cb276 | 530 | * vmbus_onoffer - Handler for channel offers from vmbus in parent partition. |
bd60c33e | 531 | * |
bd60c33e | 532 | */ |
e98cb276 | 533 | static void vmbus_onoffer(struct vmbus_channel_message_header *hdr) |
3e7ee490 | 534 | { |
bd60c33e | 535 | struct vmbus_channel_offer_channel *offer; |
188963ec | 536 | struct vmbus_channel *newchannel; |
3e7ee490 | 537 | |
bd60c33e | 538 | offer = (struct vmbus_channel_offer_channel *)hdr; |
3e7ee490 | 539 | |
454f18a9 | 540 | /* Allocate the channel object and save this offer. */ |
e98cb276 | 541 | newchannel = alloc_channel(); |
188963ec | 542 | if (!newchannel) { |
0a46618d | 543 | pr_err("Unable to allocate channel object\n"); |
3e7ee490 HJ |
544 | return; |
545 | } | |
546 | ||
132368bd S |
547 | /* |
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. | |
551 | */ | |
552 | newchannel->batched_reading = true; | |
553 | ||
b3bf60c7 S |
554 | /* |
555 | * Setup state for signalling the host. | |
556 | */ | |
557 | newchannel->sig_event = (struct hv_input_signal_event *) | |
558 | (ALIGN((unsigned long) | |
559 | &newchannel->sig_buf, | |
560 | HV_HYPERCALL_PARAM_ALIGN)); | |
561 | ||
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; | |
566 | ||
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; | |
572 | } | |
573 | ||
c50f7fb2 | 574 | memcpy(&newchannel->offermsg, offer, |
bd60c33e | 575 | sizeof(struct vmbus_channel_offer_channel)); |
c50f7fb2 HZ |
576 | newchannel->monitor_grp = (u8)offer->monitorid / 32; |
577 | newchannel->monitor_bit = (u8)offer->monitorid % 32; | |
3e7ee490 | 578 | |
2dd37cb8 | 579 | vmbus_process_offer(newchannel); |
3e7ee490 HJ |
580 | } |
581 | ||
3e189519 | 582 | /* |
e98cb276 | 583 | * vmbus_onoffer_rescind - Rescind offer handler. |
bd60c33e GKH |
584 | * |
585 | * We queue a work item to process this offer synchronously | |
586 | */ | |
e98cb276 | 587 | static void vmbus_onoffer_rescind(struct vmbus_channel_message_header *hdr) |
3e7ee490 | 588 | { |
bd60c33e | 589 | struct vmbus_channel_rescind_offer *rescind; |
aded7165 | 590 | struct vmbus_channel *channel; |
d43e2fe7 DC |
591 | unsigned long flags; |
592 | struct device *dev; | |
3e7ee490 | 593 | |
bd60c33e | 594 | rescind = (struct vmbus_channel_rescind_offer *)hdr; |
d43e2fe7 | 595 | channel = relid2channel(rescind->child_relid); |
98e08702 | 596 | |
2dd37cb8 | 597 | if (channel == NULL) { |
f52078cf DC |
598 | /* |
599 | * This is very impossible, because in | |
600 | * vmbus_process_offer(), we have already invoked | |
601 | * vmbus_release_relid() on error. | |
602 | */ | |
3e7ee490 | 603 | return; |
2dd37cb8 | 604 | } |
3e7ee490 | 605 | |
d43e2fe7 DC |
606 | spin_lock_irqsave(&channel->lock, flags); |
607 | channel->rescind = true; | |
608 | spin_unlock_irqrestore(&channel->lock, flags); | |
609 | ||
610 | if (channel->device_obj) { | |
611 | /* | |
612 | * We will have to unregister this device from the | |
613 | * driver core. | |
614 | */ | |
615 | dev = get_device(&channel->device_obj->device); | |
616 | if (dev) { | |
617 | vmbus_device_unregister(channel->device_obj); | |
618 | put_device(dev); | |
619 | } | |
620 | } else { | |
621 | hv_process_channel_removal(channel, | |
622 | channel->offermsg.child_relid); | |
2dd37cb8 | 623 | } |
3e7ee490 HJ |
624 | } |
625 | ||
3e189519 | 626 | /* |
e98cb276 HZ |
627 | * vmbus_onoffers_delivered - |
628 | * This is invoked when all offers have been delivered. | |
bd60c33e GKH |
629 | * |
630 | * Nothing to do here. | |
631 | */ | |
e98cb276 | 632 | static void vmbus_onoffers_delivered( |
bd60c33e | 633 | struct vmbus_channel_message_header *hdr) |
3e7ee490 | 634 | { |
3e7ee490 HJ |
635 | } |
636 | ||
3e189519 | 637 | /* |
e98cb276 | 638 | * vmbus_onopen_result - Open result handler. |
bd60c33e GKH |
639 | * |
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 | |
642 | * thread. | |
643 | */ | |
e98cb276 | 644 | static void vmbus_onopen_result(struct vmbus_channel_message_header *hdr) |
3e7ee490 | 645 | { |
bd60c33e | 646 | struct vmbus_channel_open_result *result; |
188963ec HZ |
647 | struct vmbus_channel_msginfo *msginfo; |
648 | struct vmbus_channel_message_header *requestheader; | |
649 | struct vmbus_channel_open_channel *openmsg; | |
dd0813b6 | 650 | unsigned long flags; |
3e7ee490 | 651 | |
bd60c33e | 652 | result = (struct vmbus_channel_open_result *)hdr; |
3e7ee490 | 653 | |
bd60c33e GKH |
654 | /* |
655 | * Find the open msg, copy the result and signal/unblock the wait event | |
656 | */ | |
15b2f647 | 657 | spin_lock_irqsave(&vmbus_connection.channelmsg_lock, flags); |
3e7ee490 | 658 | |
ebb61e5f HJ |
659 | list_for_each_entry(msginfo, &vmbus_connection.chn_msg_list, |
660 | msglistentry) { | |
188963ec | 661 | requestheader = |
c50f7fb2 | 662 | (struct vmbus_channel_message_header *)msginfo->msg; |
188963ec | 663 | |
c50f7fb2 | 664 | if (requestheader->msgtype == CHANNELMSG_OPENCHANNEL) { |
188963ec | 665 | openmsg = |
c50f7fb2 HZ |
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, | |
bd60c33e | 670 | result, |
9568a193 S |
671 | sizeof( |
672 | struct vmbus_channel_open_result)); | |
673 | complete(&msginfo->waitevent); | |
3e7ee490 HJ |
674 | break; |
675 | } | |
676 | } | |
677 | } | |
15b2f647 | 678 | spin_unlock_irqrestore(&vmbus_connection.channelmsg_lock, flags); |
3e7ee490 HJ |
679 | } |
680 | ||
3e189519 | 681 | /* |
e98cb276 | 682 | * vmbus_ongpadl_created - GPADL created handler. |
bd60c33e GKH |
683 | * |
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 | |
686 | * thread. | |
687 | */ | |
e98cb276 | 688 | static void vmbus_ongpadl_created(struct vmbus_channel_message_header *hdr) |
3e7ee490 | 689 | { |
188963ec | 690 | struct vmbus_channel_gpadl_created *gpadlcreated; |
188963ec HZ |
691 | struct vmbus_channel_msginfo *msginfo; |
692 | struct vmbus_channel_message_header *requestheader; | |
693 | struct vmbus_channel_gpadl_header *gpadlheader; | |
dd0813b6 | 694 | unsigned long flags; |
3e7ee490 | 695 | |
188963ec | 696 | gpadlcreated = (struct vmbus_channel_gpadl_created *)hdr; |
3e7ee490 | 697 | |
bd60c33e GKH |
698 | /* |
699 | * Find the establish msg, copy the result and signal/unblock the wait | |
700 | * event | |
701 | */ | |
15b2f647 | 702 | spin_lock_irqsave(&vmbus_connection.channelmsg_lock, flags); |
3e7ee490 | 703 | |
ebb61e5f HJ |
704 | list_for_each_entry(msginfo, &vmbus_connection.chn_msg_list, |
705 | msglistentry) { | |
188963ec | 706 | requestheader = |
c50f7fb2 | 707 | (struct vmbus_channel_message_header *)msginfo->msg; |
188963ec | 708 | |
c50f7fb2 | 709 | if (requestheader->msgtype == CHANNELMSG_GPADL_HEADER) { |
188963ec HZ |
710 | gpadlheader = |
711 | (struct vmbus_channel_gpadl_header *)requestheader; | |
712 | ||
c50f7fb2 HZ |
713 | if ((gpadlcreated->child_relid == |
714 | gpadlheader->child_relid) && | |
715 | (gpadlcreated->gpadl == gpadlheader->gpadl)) { | |
716 | memcpy(&msginfo->response.gpadl_created, | |
188963ec | 717 | gpadlcreated, |
9568a193 S |
718 | sizeof( |
719 | struct vmbus_channel_gpadl_created)); | |
720 | complete(&msginfo->waitevent); | |
3e7ee490 HJ |
721 | break; |
722 | } | |
723 | } | |
724 | } | |
15b2f647 | 725 | spin_unlock_irqrestore(&vmbus_connection.channelmsg_lock, flags); |
3e7ee490 HJ |
726 | } |
727 | ||
3e189519 | 728 | /* |
e98cb276 | 729 | * vmbus_ongpadl_torndown - GPADL torndown handler. |
bd60c33e GKH |
730 | * |
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 | |
733 | * thread. | |
734 | */ | |
e98cb276 | 735 | static void vmbus_ongpadl_torndown( |
bd60c33e | 736 | struct vmbus_channel_message_header *hdr) |
3e7ee490 | 737 | { |
188963ec | 738 | struct vmbus_channel_gpadl_torndown *gpadl_torndown; |
188963ec HZ |
739 | struct vmbus_channel_msginfo *msginfo; |
740 | struct vmbus_channel_message_header *requestheader; | |
741 | struct vmbus_channel_gpadl_teardown *gpadl_teardown; | |
dd0813b6 | 742 | unsigned long flags; |
3e7ee490 | 743 | |
188963ec | 744 | gpadl_torndown = (struct vmbus_channel_gpadl_torndown *)hdr; |
bd60c33e GKH |
745 | |
746 | /* | |
747 | * Find the open msg, copy the result and signal/unblock the wait event | |
748 | */ | |
15b2f647 | 749 | spin_lock_irqsave(&vmbus_connection.channelmsg_lock, flags); |
3e7ee490 | 750 | |
ebb61e5f HJ |
751 | list_for_each_entry(msginfo, &vmbus_connection.chn_msg_list, |
752 | msglistentry) { | |
188963ec | 753 | requestheader = |
c50f7fb2 | 754 | (struct vmbus_channel_message_header *)msginfo->msg; |
3e7ee490 | 755 | |
c50f7fb2 | 756 | if (requestheader->msgtype == CHANNELMSG_GPADL_TEARDOWN) { |
188963ec HZ |
757 | gpadl_teardown = |
758 | (struct vmbus_channel_gpadl_teardown *)requestheader; | |
3e7ee490 | 759 | |
c50f7fb2 HZ |
760 | if (gpadl_torndown->gpadl == gpadl_teardown->gpadl) { |
761 | memcpy(&msginfo->response.gpadl_torndown, | |
188963ec | 762 | gpadl_torndown, |
9568a193 S |
763 | sizeof( |
764 | struct vmbus_channel_gpadl_torndown)); | |
765 | complete(&msginfo->waitevent); | |
3e7ee490 HJ |
766 | break; |
767 | } | |
768 | } | |
769 | } | |
15b2f647 | 770 | spin_unlock_irqrestore(&vmbus_connection.channelmsg_lock, flags); |
3e7ee490 HJ |
771 | } |
772 | ||
3e189519 | 773 | /* |
e98cb276 | 774 | * vmbus_onversion_response - Version response handler |
bd60c33e GKH |
775 | * |
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 | |
778 | * thread. | |
779 | */ | |
e98cb276 | 780 | static void vmbus_onversion_response( |
bd60c33e | 781 | struct vmbus_channel_message_header *hdr) |
3e7ee490 | 782 | { |
188963ec HZ |
783 | struct vmbus_channel_msginfo *msginfo; |
784 | struct vmbus_channel_message_header *requestheader; | |
188963ec | 785 | struct vmbus_channel_version_response *version_response; |
dd0813b6 | 786 | unsigned long flags; |
3e7ee490 | 787 | |
188963ec | 788 | version_response = (struct vmbus_channel_version_response *)hdr; |
15b2f647 | 789 | spin_lock_irqsave(&vmbus_connection.channelmsg_lock, flags); |
3e7ee490 | 790 | |
ebb61e5f HJ |
791 | list_for_each_entry(msginfo, &vmbus_connection.chn_msg_list, |
792 | msglistentry) { | |
188963ec | 793 | requestheader = |
c50f7fb2 | 794 | (struct vmbus_channel_message_header *)msginfo->msg; |
3e7ee490 | 795 | |
c50f7fb2 HZ |
796 | if (requestheader->msgtype == |
797 | CHANNELMSG_INITIATE_CONTACT) { | |
c50f7fb2 | 798 | memcpy(&msginfo->response.version_response, |
188963ec | 799 | version_response, |
bd60c33e | 800 | sizeof(struct vmbus_channel_version_response)); |
9568a193 | 801 | complete(&msginfo->waitevent); |
3e7ee490 HJ |
802 | } |
803 | } | |
15b2f647 | 804 | spin_unlock_irqrestore(&vmbus_connection.channelmsg_lock, flags); |
3e7ee490 HJ |
805 | } |
806 | ||
c8212f04 | 807 | /* Channel message dispatch table */ |
652594c7 | 808 | struct vmbus_channel_message_table_entry |
b7c6b02f | 809 | channel_message_table[CHANNELMSG_COUNT] = { |
652594c7 DC |
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}, | |
2db84eff | 827 | {CHANNELMSG_UNLOAD_RESPONSE, 1, vmbus_unload_response}, |
c8212f04 GKH |
828 | }; |
829 | ||
3e189519 | 830 | /* |
e98cb276 | 831 | * vmbus_onmessage - Handler for channel protocol messages. |
bd60c33e GKH |
832 | * |
833 | * This is invoked in the vmbus worker thread context. | |
834 | */ | |
e98cb276 | 835 | void vmbus_onmessage(void *context) |
3e7ee490 | 836 | { |
188963ec | 837 | struct hv_message *msg = context; |
82250213 | 838 | struct vmbus_channel_message_header *hdr; |
3e7ee490 HJ |
839 | int size; |
840 | ||
f6feebe0 HZ |
841 | hdr = (struct vmbus_channel_message_header *)msg->u.payload; |
842 | size = msg->header.payload_size; | |
3e7ee490 | 843 | |
c50f7fb2 | 844 | if (hdr->msgtype >= CHANNELMSG_COUNT) { |
0a46618d | 845 | pr_err("Received invalid channel message type %d size %d\n", |
c50f7fb2 | 846 | hdr->msgtype, size); |
04f50c4d | 847 | print_hex_dump_bytes("", DUMP_PREFIX_NONE, |
f6feebe0 | 848 | (unsigned char *)msg->u.payload, size); |
3e7ee490 HJ |
849 | return; |
850 | } | |
851 | ||
b7c6b02f S |
852 | if (channel_message_table[hdr->msgtype].message_handler) |
853 | channel_message_table[hdr->msgtype].message_handler(hdr); | |
3e7ee490 | 854 | else |
0a46618d | 855 | pr_err("Unhandled channel message type %d\n", hdr->msgtype); |
3e7ee490 HJ |
856 | } |
857 | ||
3e189519 | 858 | /* |
e98cb276 | 859 | * vmbus_request_offers - Send a request to get all our pending offers. |
bd60c33e | 860 | */ |
e98cb276 | 861 | int vmbus_request_offers(void) |
3e7ee490 | 862 | { |
82250213 | 863 | struct vmbus_channel_message_header *msg; |
188963ec | 864 | struct vmbus_channel_msginfo *msginfo; |
51e5181d | 865 | int ret; |
3e7ee490 | 866 | |
188963ec | 867 | msginfo = kmalloc(sizeof(*msginfo) + |
bd60c33e GKH |
868 | sizeof(struct vmbus_channel_message_header), |
869 | GFP_KERNEL); | |
188963ec | 870 | if (!msginfo) |
75910f23 | 871 | return -ENOMEM; |
3e7ee490 | 872 | |
c50f7fb2 | 873 | msg = (struct vmbus_channel_message_header *)msginfo->msg; |
3e7ee490 | 874 | |
c50f7fb2 | 875 | msg->msgtype = CHANNELMSG_REQUESTOFFERS; |
3e7ee490 | 876 | |
3e7ee490 | 877 | |
c6977677 | 878 | ret = vmbus_post_msg(msg, |
bd60c33e GKH |
879 | sizeof(struct vmbus_channel_message_header)); |
880 | if (ret != 0) { | |
0a46618d | 881 | pr_err("Unable to request offers - %d\n", ret); |
3e7ee490 | 882 | |
0c3b7b2f S |
883 | goto cleanup; |
884 | } | |
3e7ee490 | 885 | |
0c3b7b2f | 886 | cleanup: |
dd9b15dc | 887 | kfree(msginfo); |
3e7ee490 | 888 | |
3e7ee490 HJ |
889 | return ret; |
890 | } | |
891 | ||
e68d2971 S |
892 | /* |
893 | * Retrieve the (sub) channel on which to send an outgoing request. | |
a13e8bbe S |
894 | * When a primary channel has multiple sub-channels, we try to |
895 | * distribute the load equally amongst all available channels. | |
e68d2971 S |
896 | */ |
897 | struct vmbus_channel *vmbus_get_outgoing_channel(struct vmbus_channel *primary) | |
898 | { | |
899 | struct list_head *cur, *tmp; | |
87712bf8 | 900 | int cur_cpu; |
e68d2971 S |
901 | struct vmbus_channel *cur_channel; |
902 | struct vmbus_channel *outgoing_channel = primary; | |
a13e8bbe S |
903 | int next_channel; |
904 | int i = 1; | |
e68d2971 S |
905 | |
906 | if (list_empty(&primary->sc_list)) | |
907 | return outgoing_channel; | |
908 | ||
a13e8bbe S |
909 | next_channel = primary->next_oc++; |
910 | ||
911 | if (next_channel > (primary->num_sc)) { | |
912 | primary->next_oc = 0; | |
913 | return outgoing_channel; | |
914 | } | |
915 | ||
87712bf8 S |
916 | cur_cpu = hv_context.vp_index[get_cpu()]; |
917 | put_cpu(); | |
e68d2971 S |
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) | |
921 | continue; | |
922 | ||
923 | if (cur_channel->target_vp == cur_cpu) | |
924 | return cur_channel; | |
925 | ||
a13e8bbe S |
926 | if (i == next_channel) |
927 | return cur_channel; | |
e68d2971 | 928 | |
a13e8bbe | 929 | i++; |
e68d2971 S |
930 | } |
931 | ||
932 | return outgoing_channel; | |
933 | } | |
934 | EXPORT_SYMBOL_GPL(vmbus_get_outgoing_channel); | |
935 | ||
936 | static void invoke_sc_cb(struct vmbus_channel *primary_channel) | |
937 | { | |
938 | struct list_head *cur, *tmp; | |
939 | struct vmbus_channel *cur_channel; | |
940 | ||
941 | if (primary_channel->sc_creation_callback == NULL) | |
942 | return; | |
943 | ||
944 | list_for_each_safe(cur, tmp, &primary_channel->sc_list) { | |
945 | cur_channel = list_entry(cur, struct vmbus_channel, sc_list); | |
946 | ||
947 | primary_channel->sc_creation_callback(cur_channel); | |
948 | } | |
949 | } | |
950 | ||
951 | void vmbus_set_sc_create_callback(struct vmbus_channel *primary_channel, | |
952 | void (*sc_cr_cb)(struct vmbus_channel *new_sc)) | |
953 | { | |
954 | primary_channel->sc_creation_callback = sc_cr_cb; | |
955 | } | |
956 | EXPORT_SYMBOL_GPL(vmbus_set_sc_create_callback); | |
957 | ||
958 | bool vmbus_are_subchannels_present(struct vmbus_channel *primary) | |
959 | { | |
960 | bool ret; | |
961 | ||
962 | ret = !list_empty(&primary->sc_list); | |
963 | ||
964 | if (ret) { | |
965 | /* | |
966 | * Invoke the callback on sub-channel creation. | |
967 | * This will present a uniform interface to the | |
968 | * clients. | |
969 | */ | |
970 | invoke_sc_cb(primary); | |
971 | } | |
972 | ||
973 | return ret; | |
974 | } | |
975 | EXPORT_SYMBOL_GPL(vmbus_are_subchannels_present); |