blob: af2388fdc6b9238802396ac4cac1204c219ee707 [file] [log] [blame]
Hank Janssen3e7ee492009-07-13 16:02:34 -07001/*
2 *
3 * Copyright (c) 2009, Microsoft Corporation.
4 *
5 * This program is free software; you can redistribute it and/or modify it
6 * under the terms and conditions of the GNU General Public License,
7 * version 2, as published by the Free Software Foundation.
8 *
9 * This program is distributed in the hope it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
12 * more details.
13 *
14 * You should have received a copy of the GNU General Public License along with
15 * this program; if not, write to the Free Software Foundation, Inc., 59 Temple
16 * Place - Suite 330, Boston, MA 02111-1307 USA.
17 *
18 * Authors:
19 * Haiyang Zhang <haiyangz@microsoft.com>
20 * Hank Janssen <hjanssen@microsoft.com>
21 *
22 */
Hank Janssen0a466182011-03-29 13:58:47 -070023#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
24
Greg Kroah-Hartmana0086dc2009-08-17 17:22:08 -070025#include <linux/kernel.h>
K. Y. Srinivasan0c3b7b22011-02-11 09:59:43 -080026#include <linux/sched.h>
27#include <linux/wait.h>
K. Y. Srinivasan5289d3d2011-08-25 09:49:01 -070028#include <linux/delay.h>
Greg Kroah-Hartmana0086dc2009-08-17 17:22:08 -070029#include <linux/mm.h>
Tejun Heo5a0e3ad2010-03-24 17:04:11 +090030#include <linux/slab.h>
Greg Kroah-Hartmana0086dc2009-08-17 17:22:08 -070031#include <linux/vmalloc.h>
Greg Kroah-Hartman46a97192011-10-04 12:29:52 -070032#include <linux/hyperv.h>
K. Y. Srinivasan37f72782012-12-01 06:46:41 -080033#include <linux/export.h>
Greg Kroah-Hartman407dd162011-10-11 08:36:44 -060034#include <asm/hyperv.h>
K. Y. Srinivasan0f2a6612011-05-12 19:34:28 -070035#include "hyperv_vmbus.h"
Hank Janssen3e7ee492009-07-13 16:02:34 -070036
Hank Janssen3e7ee492009-07-13 16:02:34 -070037
Haiyang Zhangda9fcb72011-01-26 12:12:14 -080038struct vmbus_connection vmbus_connection = {
39 .conn_state = DISCONNECTED,
40 .next_gpadl_handle = ATOMIC_INIT(0xE1E10),
Hank Janssen3e7ee492009-07-13 16:02:34 -070041};
42
Hank Janssen3e189512010-03-04 22:11:00 +000043/*
K. Y. Srinivasan37f72782012-12-01 06:46:41 -080044 * Negotiated protocol version with the host.
45 */
46__u32 vmbus_proto_version;
47EXPORT_SYMBOL_GPL(vmbus_proto_version);
48
K. Y. Srinivasan610071c2012-12-01 06:46:38 -080049static __u32 vmbus_get_next_version(__u32 current_version)
50{
51 switch (current_version) {
52 case (VERSION_WIN7):
53 return VERSION_WS2008;
54
55 case (VERSION_WIN8):
56 return VERSION_WIN7;
57
K. Y. Srinivasan03367ef2014-04-03 18:02:45 -070058 case (VERSION_WIN8_1):
59 return VERSION_WIN8;
60
K. Y. Srinivasan610071c2012-12-01 06:46:38 -080061 case (VERSION_WS2008):
62 default:
63 return VERSION_INVAL;
64 }
65}
66
67static int vmbus_negotiate_version(struct vmbus_channel_msginfo *msginfo,
68 __u32 version)
69{
70 int ret = 0;
71 struct vmbus_channel_initiate_contact *msg;
72 unsigned long flags;
K. Y. Srinivasan610071c2012-12-01 06:46:38 -080073
74 init_completion(&msginfo->waitevent);
75
76 msg = (struct vmbus_channel_initiate_contact *)msginfo->msg;
77
78 msg->header.msgtype = CHANNELMSG_INITIATE_CONTACT;
79 msg->vmbus_version_requested = version;
80 msg->interrupt_page = virt_to_phys(vmbus_connection.int_page);
Greg Kroah-Hartman8681db42013-09-13 11:32:55 -070081 msg->monitor_page1 = virt_to_phys(vmbus_connection.monitor_pages[0]);
82 msg->monitor_page2 = virt_to_phys(vmbus_connection.monitor_pages[1]);
K. Y. Srinivasan87712bf82014-12-14 23:34:51 -080083 if (version == VERSION_WIN8_1) {
84 msg->target_vcpu = hv_context.vp_index[get_cpu()];
85 put_cpu();
86 }
K. Y. Srinivasan610071c2012-12-01 06:46:38 -080087
88 /*
89 * Add to list before we send the request since we may
90 * receive the response before returning from this routine
91 */
92 spin_lock_irqsave(&vmbus_connection.channelmsg_lock, flags);
93 list_add_tail(&msginfo->msglistentry,
94 &vmbus_connection.chn_msg_list);
95
96 spin_unlock_irqrestore(&vmbus_connection.channelmsg_lock, flags);
97
98 ret = vmbus_post_msg(msg,
99 sizeof(struct vmbus_channel_initiate_contact));
100 if (ret != 0) {
101 spin_lock_irqsave(&vmbus_connection.channelmsg_lock, flags);
102 list_del(&msginfo->msglistentry);
103 spin_unlock_irqrestore(&vmbus_connection.channelmsg_lock,
104 flags);
105 return ret;
106 }
107
108 /* Wait for the connection response */
K. Y. Srinivasan269f9792014-01-16 11:59:58 -0800109 wait_for_completion(&msginfo->waitevent);
K. Y. Srinivasan610071c2012-12-01 06:46:38 -0800110
111 spin_lock_irqsave(&vmbus_connection.channelmsg_lock, flags);
112 list_del(&msginfo->msglistentry);
113 spin_unlock_irqrestore(&vmbus_connection.channelmsg_lock, flags);
114
115 /* Check if successful */
116 if (msginfo->response.version_response.version_supported) {
117 vmbus_connection.conn_state = CONNECTED;
118 } else {
K. Y. Srinivasan610071c2012-12-01 06:46:38 -0800119 return -ECONNREFUSED;
120 }
121
122 return ret;
123}
124
125/*
Haiyang Zhangc6977672011-01-26 12:12:08 -0800126 * vmbus_connect - Sends a connect request on the partition service connection
Greg Kroah-Hartmanfd8b85e2009-08-31 11:40:14 -0700127 */
Haiyang Zhangc6977672011-01-26 12:12:08 -0800128int vmbus_connect(void)
Hank Janssen3e7ee492009-07-13 16:02:34 -0700129{
Greg Kroah-Hartmanfd8b85e2009-08-31 11:40:14 -0700130 int ret = 0;
Haiyang Zhang15b2f642011-01-26 12:12:07 -0800131 struct vmbus_channel_msginfo *msginfo = NULL;
K. Y. Srinivasan610071c2012-12-01 06:46:38 -0800132 __u32 version;
Hank Janssen3e7ee492009-07-13 16:02:34 -0700133
Bill Pemberton454f18a2009-07-27 16:47:24 -0400134 /* Initialize the vmbus connection */
Haiyang Zhangda9fcb72011-01-26 12:12:14 -0800135 vmbus_connection.conn_state = CONNECTING;
136 vmbus_connection.work_queue = create_workqueue("hv_vmbus_con");
137 if (!vmbus_connection.work_queue) {
K. Y. Srinivasan3a7546d2011-06-06 15:50:10 -0700138 ret = -ENOMEM;
K. Y. Srinivasanb0043862011-05-10 07:55:44 -0700139 goto cleanup;
Bill Pembertonde65a382009-07-29 17:00:09 -0400140 }
Hank Janssen3e7ee492009-07-13 16:02:34 -0700141
Haiyang Zhangda9fcb72011-01-26 12:12:14 -0800142 INIT_LIST_HEAD(&vmbus_connection.chn_msg_list);
Haiyang Zhang15b2f642011-01-26 12:12:07 -0800143 spin_lock_init(&vmbus_connection.channelmsg_lock);
Hank Janssen3e7ee492009-07-13 16:02:34 -0700144
Haiyang Zhangda9fcb72011-01-26 12:12:14 -0800145 INIT_LIST_HEAD(&vmbus_connection.chn_list);
Haiyang Zhang15b2f642011-01-26 12:12:07 -0800146 spin_lock_init(&vmbus_connection.channel_lock);
Hank Janssen3e7ee492009-07-13 16:02:34 -0700147
Bill Pemberton454f18a2009-07-27 16:47:24 -0400148 /*
149 * Setup the vmbus event connection for channel interrupt
150 * abstraction stuff
151 */
K. Y. Srinivasandf3493e2011-02-11 09:59:00 -0800152 vmbus_connection.int_page =
153 (void *)__get_free_pages(GFP_KERNEL|__GFP_ZERO, 0);
Haiyang Zhangda9fcb72011-01-26 12:12:14 -0800154 if (vmbus_connection.int_page == NULL) {
K. Y. Srinivasan3a7546d2011-06-06 15:50:10 -0700155 ret = -ENOMEM;
K. Y. Srinivasanb0043862011-05-10 07:55:44 -0700156 goto cleanup;
Hank Janssen3e7ee492009-07-13 16:02:34 -0700157 }
158
Haiyang Zhangda9fcb72011-01-26 12:12:14 -0800159 vmbus_connection.recv_int_page = vmbus_connection.int_page;
160 vmbus_connection.send_int_page =
161 (void *)((unsigned long)vmbus_connection.int_page +
Greg Kroah-Hartmanfd8b85e2009-08-31 11:40:14 -0700162 (PAGE_SIZE >> 1));
Hank Janssen3e7ee492009-07-13 16:02:34 -0700163
Greg Kroah-Hartmanfd8b85e2009-08-31 11:40:14 -0700164 /*
165 * Setup the monitor notification facility. The 1st page for
166 * parent->child and the 2nd page for child->parent
Bill Pemberton454f18a2009-07-27 16:47:24 -0400167 */
Greg Kroah-Hartman8681db42013-09-13 11:32:55 -0700168 vmbus_connection.monitor_pages[0] = (void *)__get_free_pages((GFP_KERNEL|__GFP_ZERO), 0);
169 vmbus_connection.monitor_pages[1] = (void *)__get_free_pages((GFP_KERNEL|__GFP_ZERO), 0);
170 if ((vmbus_connection.monitor_pages[0] == NULL) ||
171 (vmbus_connection.monitor_pages[1] == NULL)) {
K. Y. Srinivasan3a7546d2011-06-06 15:50:10 -0700172 ret = -ENOMEM;
K. Y. Srinivasanb0043862011-05-10 07:55:44 -0700173 goto cleanup;
Hank Janssen3e7ee492009-07-13 16:02:34 -0700174 }
175
Haiyang Zhang15b2f642011-01-26 12:12:07 -0800176 msginfo = kzalloc(sizeof(*msginfo) +
Greg Kroah-Hartmanfd8b85e2009-08-31 11:40:14 -0700177 sizeof(struct vmbus_channel_initiate_contact),
178 GFP_KERNEL);
Haiyang Zhang15b2f642011-01-26 12:12:07 -0800179 if (msginfo == NULL) {
Bill Pemberton8cad0af2010-05-05 15:27:32 -0400180 ret = -ENOMEM;
K. Y. Srinivasanb0043862011-05-10 07:55:44 -0700181 goto cleanup;
Hank Janssen3e7ee492009-07-13 16:02:34 -0700182 }
183
Bill Pemberton454f18a2009-07-27 16:47:24 -0400184 /*
K. Y. Srinivasan610071c2012-12-01 06:46:38 -0800185 * Negotiate a compatible VMBUS version number with the
186 * host. We start with the highest number we can support
187 * and work our way down until we negotiate a compatible
188 * version.
Bill Pemberton454f18a2009-07-27 16:47:24 -0400189 */
Bill Pemberton53af5452009-09-11 21:46:44 -0400190
K. Y. Srinivasan2a5c43a2012-12-01 06:46:56 -0800191 version = VERSION_CURRENT;
Hank Janssen3e7ee492009-07-13 16:02:34 -0700192
K. Y. Srinivasan610071c2012-12-01 06:46:38 -0800193 do {
194 ret = vmbus_negotiate_version(msginfo, version);
K. Y. Srinivasan8bbf9f42013-09-04 15:41:58 -0700195 if (ret == -ETIMEDOUT)
K. Y. Srinivasan666b9ad2013-08-28 14:56:54 -0700196 goto cleanup;
197
198 if (vmbus_connection.conn_state == CONNECTED)
K. Y. Srinivasan610071c2012-12-01 06:46:38 -0800199 break;
200
201 version = vmbus_get_next_version(version);
202 } while (version != VERSION_INVAL);
203
204 if (version == VERSION_INVAL)
K. Y. Srinivasanb0043862011-05-10 07:55:44 -0700205 goto cleanup;
Hank Janssen3e7ee492009-07-13 16:02:34 -0700206
K. Y. Srinivasan37f72782012-12-01 06:46:41 -0800207 vmbus_proto_version = version;
K. Y. Srinivasan3bacaf0c2012-12-01 06:46:59 -0800208 pr_info("Hyper-V Host Build:%d-%d.%d-%d-%d.%d; Vmbus version:%d.%d\n",
209 host_info_eax, host_info_ebx >> 16,
210 host_info_ebx & 0xFFFF, host_info_ecx,
211 host_info_edx >> 24, host_info_edx & 0xFFFFFF,
212 version >> 16, version & 0xFFFF);
213
Haiyang Zhang15b2f642011-01-26 12:12:07 -0800214 kfree(msginfo);
Hank Janssen3e7ee492009-07-13 16:02:34 -0700215 return 0;
216
K. Y. Srinivasanb0043862011-05-10 07:55:44 -0700217cleanup:
K. Y. Srinivasan3bacaf0c2012-12-01 06:46:59 -0800218 pr_err("Unable to connect to host\n");
Hank Janssen3e7ee492009-07-13 16:02:34 -0700219
Vitaly Kuznetsov09a19622015-02-27 11:25:54 -0800220 vmbus_connection.conn_state = DISCONNECTED;
221 vmbus_disconnect();
222
223 kfree(msginfo);
224
225 return ret;
226}
227
228void vmbus_disconnect(void)
229{
230 if (vmbus_connection.work_queue) {
231 drain_workqueue(vmbus_connection.work_queue);
Haiyang Zhangda9fcb72011-01-26 12:12:14 -0800232 destroy_workqueue(vmbus_connection.work_queue);
Vitaly Kuznetsov09a19622015-02-27 11:25:54 -0800233 }
Hank Janssen3e7ee492009-07-13 16:02:34 -0700234
Haiyang Zhangda9fcb72011-01-26 12:12:14 -0800235 if (vmbus_connection.int_page) {
K. Y. Srinivasandf3493e2011-02-11 09:59:00 -0800236 free_pages((unsigned long)vmbus_connection.int_page, 0);
Haiyang Zhangda9fcb72011-01-26 12:12:14 -0800237 vmbus_connection.int_page = NULL;
Hank Janssen3e7ee492009-07-13 16:02:34 -0700238 }
239
Radim Krčmářa100d88d2014-05-27 19:16:20 +0200240 free_pages((unsigned long)vmbus_connection.monitor_pages[0], 0);
241 free_pages((unsigned long)vmbus_connection.monitor_pages[1], 0);
Greg Kroah-Hartman8681db42013-09-13 11:32:55 -0700242 vmbus_connection.monitor_pages[0] = NULL;
243 vmbus_connection.monitor_pages[1] = NULL;
Hank Janssen3e7ee492009-07-13 16:02:34 -0700244}
245
K. Y. Srinivasan3a28fa32014-04-08 18:45:54 -0700246/*
247 * Map the given relid to the corresponding channel based on the
248 * per-cpu list of channels that have been affinitized to this CPU.
249 * This will be used in the channel callback path as we can do this
250 * mapping in a lock-free fashion.
251 */
252static struct vmbus_channel *pcpu_relid2channel(u32 relid)
253{
254 struct vmbus_channel *channel;
255 struct vmbus_channel *found_channel = NULL;
256 int cpu = smp_processor_id();
257 struct list_head *pcpu_head = &hv_context.percpu_list[cpu];
258
259 list_for_each_entry(channel, pcpu_head, percpu_list) {
260 if (channel->offermsg.child_relid == relid) {
261 found_channel = channel;
262 break;
263 }
264 }
265
266 return found_channel;
267}
Hank Janssen3e7ee492009-07-13 16:02:34 -0700268
Hank Janssen3e189512010-03-04 22:11:00 +0000269/*
Haiyang Zhangc6977672011-01-26 12:12:08 -0800270 * relid2channel - Get the channel object given its
271 * child relative id (ie channel id)
Greg Kroah-Hartmanfd8b85e2009-08-31 11:40:14 -0700272 */
Haiyang Zhangc6977672011-01-26 12:12:08 -0800273struct vmbus_channel *relid2channel(u32 relid)
Hank Janssen3e7ee492009-07-13 16:02:34 -0700274{
Greg Kroah-Hartmanaded7162009-08-18 15:21:19 -0700275 struct vmbus_channel *channel;
Haiyang Zhang15b2f642011-01-26 12:12:07 -0800276 struct vmbus_channel *found_channel = NULL;
Greg Kroah-Hartman0f5e44c2009-07-15 14:57:16 -0700277 unsigned long flags;
K. Y. Srinivasane68d2972013-05-23 12:02:32 -0700278 struct list_head *cur, *tmp;
279 struct vmbus_channel *cur_sc;
Hank Janssen3e7ee492009-07-13 16:02:34 -0700280
Haiyang Zhang15b2f642011-01-26 12:12:07 -0800281 spin_lock_irqsave(&vmbus_connection.channel_lock, flags);
Haiyang Zhangda9fcb72011-01-26 12:12:14 -0800282 list_for_each_entry(channel, &vmbus_connection.chn_list, listentry) {
Haiyang Zhang15b2f642011-01-26 12:12:07 -0800283 if (channel->offermsg.child_relid == relid) {
284 found_channel = channel;
Hank Janssen3e7ee492009-07-13 16:02:34 -0700285 break;
K. Y. Srinivasane68d2972013-05-23 12:02:32 -0700286 } else if (!list_empty(&channel->sc_list)) {
287 /*
288 * Deal with sub-channels.
289 */
290 list_for_each_safe(cur, tmp, &channel->sc_list) {
291 cur_sc = list_entry(cur, struct vmbus_channel,
292 sc_list);
293 if (cur_sc->offermsg.child_relid == relid) {
294 found_channel = cur_sc;
295 break;
296 }
297 }
Hank Janssen3e7ee492009-07-13 16:02:34 -0700298 }
299 }
Haiyang Zhang15b2f642011-01-26 12:12:07 -0800300 spin_unlock_irqrestore(&vmbus_connection.channel_lock, flags);
Hank Janssen3e7ee492009-07-13 16:02:34 -0700301
Haiyang Zhang15b2f642011-01-26 12:12:07 -0800302 return found_channel;
Hank Janssen3e7ee492009-07-13 16:02:34 -0700303}
304
Hank Janssen3e189512010-03-04 22:11:00 +0000305/*
Haiyang Zhangc6977672011-01-26 12:12:08 -0800306 * process_chn_event - Process a channel event notification
Greg Kroah-Hartmanfd8b85e2009-08-31 11:40:14 -0700307 */
Olaf Hering35436482011-04-16 18:50:40 +0200308static void process_chn_event(u32 relid)
Hank Janssen3e7ee492009-07-13 16:02:34 -0700309{
Greg Kroah-Hartmanaded7162009-08-18 15:21:19 -0700310 struct vmbus_channel *channel;
K. Y. Srinivasanf878f3d2012-12-01 06:46:35 -0800311 void *arg;
312 bool read_state;
313 u32 bytes_to_read;
Hank Janssen3e7ee492009-07-13 16:02:34 -0700314
Bill Pemberton454f18a2009-07-27 16:47:24 -0400315 /*
316 * Find the channel based on this relid and invokes the
317 * channel callback to process the event
318 */
K. Y. Srinivasan3a28fa32014-04-08 18:45:54 -0700319 channel = pcpu_relid2channel(relid);
Hank Janssen3e7ee492009-07-13 16:02:34 -0700320
K. Y. Srinivasan24326032011-08-31 14:35:57 -0700321 if (!channel) {
322 pr_err("channel not found for relid - %u\n", relid);
323 return;
324 }
325
326 /*
327 * A channel once created is persistent even when there
328 * is no driver handling the device. An unloading driver
K. Y. Srinivasand3ba7202014-04-08 18:45:53 -0700329 * sets the onchannel_callback to NULL on the same CPU
330 * as where this interrupt is handled (in an interrupt context).
331 * Thus, checking and invoking the driver specific callback takes
332 * care of orderly unloading of the driver.
K. Y. Srinivasan24326032011-08-31 14:35:57 -0700333 */
334
K. Y. Srinivasanf878f3d2012-12-01 06:46:35 -0800335 if (channel->onchannel_callback != NULL) {
336 arg = channel->channel_callback_context;
337 read_state = channel->batched_reading;
338 /*
339 * This callback reads the messages sent by the host.
340 * We can optimize host to guest signaling by ensuring:
341 * 1. While reading the channel, we disable interrupts from
342 * host.
343 * 2. Ensure that we process all posted messages from the host
344 * before returning from this callback.
345 * 3. Once we return, enable signaling from the host. Once this
346 * state is set we check to see if additional packets are
347 * available to read. In this case we repeat the process.
348 */
349
350 do {
K. Y. Srinivasanaffb1af2014-07-07 16:34:24 -0700351 if (read_state)
352 hv_begin_read(&channel->inbound);
K. Y. Srinivasanf878f3d2012-12-01 06:46:35 -0800353 channel->onchannel_callback(arg);
K. Y. Srinivasanaffb1af2014-07-07 16:34:24 -0700354 if (read_state)
355 bytes_to_read = hv_end_read(&channel->inbound);
356 else
357 bytes_to_read = 0;
K. Y. Srinivasanf878f3d2012-12-01 06:46:35 -0800358 } while (read_state && (bytes_to_read != 0));
359 } else {
K. Y. Srinivasan24326032011-08-31 14:35:57 -0700360 pr_err("no channel callback for relid - %u\n", relid);
K. Y. Srinivasanf878f3d2012-12-01 06:46:35 -0800361 }
K. Y. Srinivasand9add43b2011-08-27 11:31:43 -0700362
Hank Janssen3e7ee492009-07-13 16:02:34 -0700363}
364
Hank Janssen3e189512010-03-04 22:11:00 +0000365/*
Haiyang Zhangc6977672011-01-26 12:12:08 -0800366 * vmbus_on_event - Handler for events
Greg Kroah-Hartmanfd8b85e2009-08-31 11:40:14 -0700367 */
K. Y. Srinivasan6de3d6a2011-03-10 14:05:16 -0800368void vmbus_on_event(unsigned long data)
Hank Janssen3e7ee492009-07-13 16:02:34 -0700369{
Olaf Hering35436482011-04-16 18:50:40 +0200370 u32 dword;
K. Y. Srinivasan6552ecd2012-12-01 06:46:49 -0800371 u32 maxdword;
Hank Janssen3e7ee492009-07-13 16:02:34 -0700372 int bit;
Olaf Hering35436482011-04-16 18:50:40 +0200373 u32 relid;
K. Y. Srinivasan6552ecd2012-12-01 06:46:49 -0800374 u32 *recv_int_page = NULL;
375 void *page_addr;
376 int cpu = smp_processor_id();
377 union hv_synic_event_flags *event;
378
379 if ((vmbus_proto_version == VERSION_WS2008) ||
380 (vmbus_proto_version == VERSION_WIN7)) {
381 maxdword = MAX_NUM_CHANNELS_SUPPORTED >> 5;
382 recv_int_page = vmbus_connection.recv_int_page;
383 } else {
384 /*
385 * When the host is win8 and beyond, the event page
386 * can be directly checked to get the id of the channel
387 * that has the interrupt pending.
388 */
389 maxdword = HV_EVENT_FLAGS_DWORD_COUNT;
390 page_addr = hv_context.synic_event_page[cpu];
391 event = (union hv_synic_event_flags *)page_addr +
392 VMBUS_MESSAGE_SINT;
393 recv_int_page = event->flags32;
394 }
395
396
Hank Janssen3e7ee492009-07-13 16:02:34 -0700397
Bill Pemberton454f18a2009-07-27 16:47:24 -0400398 /* Check events */
Olaf Hering242b45a2011-04-16 18:50:39 +0200399 if (!recv_int_page)
400 return;
401 for (dword = 0; dword < maxdword; dword++) {
402 if (!recv_int_page[dword])
403 continue;
404 for (bit = 0; bit < 32; bit++) {
K. Y. Srinivasand9add43b2011-08-27 11:31:43 -0700405 if (sync_test_and_clear_bit(bit,
406 (unsigned long *)&recv_int_page[dword])) {
Olaf Hering242b45a2011-04-16 18:50:39 +0200407 relid = (dword << 5) + bit;
Hank Janssen3e7ee492009-07-13 16:02:34 -0700408
K. Y. Srinivasand9add43b2011-08-27 11:31:43 -0700409 if (relid == 0)
K. Y. Srinivasan6d81d332011-05-10 07:55:45 -0700410 /*
411 * Special case - vmbus
412 * channel protocol msg
413 */
Olaf Hering242b45a2011-04-16 18:50:39 +0200414 continue;
K. Y. Srinivasand9add43b2011-08-27 11:31:43 -0700415
Olaf Hering35436482011-04-16 18:50:40 +0200416 process_chn_event(relid);
Hank Janssen3e7ee492009-07-13 16:02:34 -0700417 }
Olaf Hering242b45a2011-04-16 18:50:39 +0200418 }
Hank Janssen3e7ee492009-07-13 16:02:34 -0700419 }
Hank Janssen3e7ee492009-07-13 16:02:34 -0700420}
421
Hank Janssen3e189512010-03-04 22:11:00 +0000422/*
Haiyang Zhangc6977672011-01-26 12:12:08 -0800423 * vmbus_post_msg - Send a msg on the vmbus's message connection
Greg Kroah-Hartmanfd8b85e2009-08-31 11:40:14 -0700424 */
Haiyang Zhangc6977672011-01-26 12:12:08 -0800425int vmbus_post_msg(void *buffer, size_t buflen)
Hank Janssen3e7ee492009-07-13 16:02:34 -0700426{
Haiyang Zhang15b2f642011-01-26 12:12:07 -0800427 union hv_connection_id conn_id;
K. Y. Srinivasan5289d3d2011-08-25 09:49:01 -0700428 int ret = 0;
429 int retries = 0;
Hank Janssen3e7ee492009-07-13 16:02:34 -0700430
Haiyang Zhang15b2f642011-01-26 12:12:07 -0800431 conn_id.asu32 = 0;
432 conn_id.u.id = VMBUS_MESSAGE_CONNECTION_ID;
K. Y. Srinivasan5289d3d2011-08-25 09:49:01 -0700433
434 /*
435 * hv_post_message() can have transient failures because of
436 * insufficient resources. Retry the operation a couple of
437 * times before giving up.
438 */
K. Y. Srinivasanfdeebcc2014-08-27 16:25:31 -0700439 while (retries < 10) {
440 ret = hv_post_message(conn_id, 1, buffer, buflen);
441
442 switch (ret) {
Dexuan Cui89f9f672015-02-27 11:25:59 -0800443 case HV_STATUS_INVALID_CONNECTION_ID:
444 /*
445 * We could get this if we send messages too
446 * frequently.
447 */
448 ret = -EAGAIN;
449 break;
450 case HV_STATUS_INSUFFICIENT_MEMORY:
K. Y. Srinivasanfdeebcc2014-08-27 16:25:31 -0700451 case HV_STATUS_INSUFFICIENT_BUFFERS:
452 ret = -ENOMEM;
K. Y. Srinivasanfdeebcc2014-08-27 16:25:31 -0700453 break;
454 case HV_STATUS_SUCCESS:
K. Y. Srinivasan5289d3d2011-08-25 09:49:01 -0700455 return ret;
K. Y. Srinivasanfdeebcc2014-08-27 16:25:31 -0700456 default:
457 pr_err("hv_post_msg() failed; error code:%d\n", ret);
458 return -EINVAL;
459 }
460
K. Y. Srinivasan5289d3d2011-08-25 09:49:01 -0700461 retries++;
Dexuan Cui89f9f672015-02-27 11:25:59 -0800462 msleep(1000);
K. Y. Srinivasan5289d3d2011-08-25 09:49:01 -0700463 }
464 return ret;
Hank Janssen3e7ee492009-07-13 16:02:34 -0700465}
466
Hank Janssen3e189512010-03-04 22:11:00 +0000467/*
Haiyang Zhangc6977672011-01-26 12:12:08 -0800468 * vmbus_set_event - Send an event notification to the parent
Greg Kroah-Hartmanfd8b85e2009-08-31 11:40:14 -0700469 */
K. Y. Srinivasan21c3bef2012-12-01 06:46:43 -0800470int vmbus_set_event(struct vmbus_channel *channel)
Hank Janssen3e7ee492009-07-13 16:02:34 -0700471{
K. Y. Srinivasan21c3bef2012-12-01 06:46:43 -0800472 u32 child_relid = channel->offermsg.child_relid;
Bill Pemberton7c369f42009-07-29 17:00:11 -0400473
K. Y. Srinivasan3be77772012-12-01 06:46:46 -0800474 if (!channel->is_dedicated_interrupt) {
475 /* Each u32 represents 32 channels */
476 sync_set_bit(child_relid & 31,
477 (unsigned long *)vmbus_connection.send_int_page +
478 (child_relid >> 5));
479 }
480
481 return hv_signal_event(channel->sig_event);
Hank Janssen3e7ee492009-07-13 16:02:34 -0700482}