#include <linux/slab.h>
#include <linux/vmalloc.h>
#include <linux/hyperv.h>
+#include <linux/export.h>
#include <asm/hyperv.h>
#include "hyperv_vmbus.h"
.next_gpadl_handle = ATOMIC_INIT(0xE1E10),
};
+/*
+ * Negotiated protocol version with the host.
+ */
+__u32 vmbus_proto_version;
+EXPORT_SYMBOL_GPL(vmbus_proto_version);
+
+static __u32 vmbus_get_next_version(__u32 current_version)
+{
+ switch (current_version) {
+ case (VERSION_WIN7):
+ return VERSION_WS2008;
+
+ case (VERSION_WIN8):
+ return VERSION_WIN7;
+
+ case (VERSION_WS2008):
+ default:
+ return VERSION_INVAL;
+ }
+}
+
+static int vmbus_negotiate_version(struct vmbus_channel_msginfo *msginfo,
+ __u32 version)
+{
+ int ret = 0;
+ struct vmbus_channel_initiate_contact *msg;
+ unsigned long flags;
+ int t;
+
+ init_completion(&msginfo->waitevent);
+
+ msg = (struct vmbus_channel_initiate_contact *)msginfo->msg;
+
+ msg->header.msgtype = CHANNELMSG_INITIATE_CONTACT;
+ msg->vmbus_version_requested = version;
+ msg->interrupt_page = virt_to_phys(vmbus_connection.int_page);
+ msg->monitor_page1 = virt_to_phys(vmbus_connection.monitor_pages);
+ msg->monitor_page2 = virt_to_phys(
+ (void *)((unsigned long)vmbus_connection.monitor_pages +
+ PAGE_SIZE));
+
+ /*
+ * Add to list before we send the request since we may
+ * receive the response before returning from this routine
+ */
+ spin_lock_irqsave(&vmbus_connection.channelmsg_lock, flags);
+ list_add_tail(&msginfo->msglistentry,
+ &vmbus_connection.chn_msg_list);
+
+ spin_unlock_irqrestore(&vmbus_connection.channelmsg_lock, flags);
+
+ ret = vmbus_post_msg(msg,
+ sizeof(struct vmbus_channel_initiate_contact));
+ if (ret != 0) {
+ spin_lock_irqsave(&vmbus_connection.channelmsg_lock, flags);
+ list_del(&msginfo->msglistentry);
+ spin_unlock_irqrestore(&vmbus_connection.channelmsg_lock,
+ flags);
+ return ret;
+ }
+
+ /* Wait for the connection response */
+ t = wait_for_completion_timeout(&msginfo->waitevent, 5*HZ);
+ if (t == 0) {
+ spin_lock_irqsave(&vmbus_connection.channelmsg_lock,
+ flags);
+ list_del(&msginfo->msglistentry);
+ spin_unlock_irqrestore(&vmbus_connection.channelmsg_lock,
+ flags);
+ return -ETIMEDOUT;
+ }
+
+ spin_lock_irqsave(&vmbus_connection.channelmsg_lock, flags);
+ list_del(&msginfo->msglistentry);
+ spin_unlock_irqrestore(&vmbus_connection.channelmsg_lock, flags);
+
+ /* Check if successful */
+ if (msginfo->response.version_response.version_supported) {
+ vmbus_connection.conn_state = CONNECTED;
+ } else {
+ return -ECONNREFUSED;
+ }
+
+ return ret;
+}
+
/*
* vmbus_connect - Sends a connect request on the partition service connection
*/
int vmbus_connect(void)
{
int ret = 0;
- int t;
struct vmbus_channel_msginfo *msginfo = NULL;
- struct vmbus_channel_initiate_contact *msg;
- unsigned long flags;
+ __u32 version;
/* Initialize the vmbus connection */
vmbus_connection.conn_state = CONNECTING;
goto cleanup;
}
- init_completion(&msginfo->waitevent);
-
- msg = (struct vmbus_channel_initiate_contact *)msginfo->msg;
-
- msg->header.msgtype = CHANNELMSG_INITIATE_CONTACT;
- msg->vmbus_version_requested = VMBUS_REVISION_NUMBER;
- msg->interrupt_page = virt_to_phys(vmbus_connection.int_page);
- msg->monitor_page1 = virt_to_phys(vmbus_connection.monitor_pages);
- msg->monitor_page2 = virt_to_phys(
- (void *)((unsigned long)vmbus_connection.monitor_pages +
- PAGE_SIZE));
-
/*
- * Add to list before we send the request since we may
- * receive the response before returning from this routine
+ * Negotiate a compatible VMBUS version number with the
+ * host. We start with the highest number we can support
+ * and work our way down until we negotiate a compatible
+ * version.
*/
- spin_lock_irqsave(&vmbus_connection.channelmsg_lock, flags);
- list_add_tail(&msginfo->msglistentry,
- &vmbus_connection.chn_msg_list);
- spin_unlock_irqrestore(&vmbus_connection.channelmsg_lock, flags);
+ version = VERSION_CURRENT;
- ret = vmbus_post_msg(msg,
- sizeof(struct vmbus_channel_initiate_contact));
- if (ret != 0) {
- spin_lock_irqsave(&vmbus_connection.channelmsg_lock, flags);
- list_del(&msginfo->msglistentry);
- spin_unlock_irqrestore(&vmbus_connection.channelmsg_lock,
- flags);
- goto cleanup;
- }
+ do {
+ ret = vmbus_negotiate_version(msginfo, version);
+ if (ret == 0)
+ break;
- /* Wait for the connection response */
- t = wait_for_completion_timeout(&msginfo->waitevent, 5*HZ);
- if (t == 0) {
- spin_lock_irqsave(&vmbus_connection.channelmsg_lock,
- flags);
- list_del(&msginfo->msglistentry);
- spin_unlock_irqrestore(&vmbus_connection.channelmsg_lock,
- flags);
- ret = -ETIMEDOUT;
- goto cleanup;
- }
+ version = vmbus_get_next_version(version);
+ } while (version != VERSION_INVAL);
- spin_lock_irqsave(&vmbus_connection.channelmsg_lock, flags);
- list_del(&msginfo->msglistentry);
- spin_unlock_irqrestore(&vmbus_connection.channelmsg_lock, flags);
-
- /* Check if successful */
- if (msginfo->response.version_response.version_supported) {
- vmbus_connection.conn_state = CONNECTED;
- } else {
- pr_err("Unable to connect, "
- "Version %d not supported by Hyper-V\n",
- VMBUS_REVISION_NUMBER);
- ret = -ECONNREFUSED;
+ if (version == VERSION_INVAL)
goto cleanup;
- }
+
+ vmbus_proto_version = version;
+ pr_info("Hyper-V Host Build:%d-%d.%d-%d-%d.%d; Vmbus version:%d.%d\n",
+ host_info_eax, host_info_ebx >> 16,
+ host_info_ebx & 0xFFFF, host_info_ecx,
+ host_info_edx >> 24, host_info_edx & 0xFFFFFF,
+ version >> 16, version & 0xFFFF);
kfree(msginfo);
return 0;
cleanup:
+ pr_err("Unable to connect to host\n");
vmbus_connection.conn_state = DISCONNECTED;
if (vmbus_connection.work_queue)
{
struct vmbus_channel *channel;
unsigned long flags;
+ void *arg;
+ bool read_state;
+ u32 bytes_to_read;
/*
* Find the channel based on this relid and invokes the
*/
spin_lock_irqsave(&channel->inbound_lock, flags);
- if (channel->onchannel_callback != NULL)
- channel->onchannel_callback(channel->channel_callback_context);
- else
+ if (channel->onchannel_callback != NULL) {
+ arg = channel->channel_callback_context;
+ read_state = channel->batched_reading;
+ /*
+ * This callback reads the messages sent by the host.
+ * We can optimize host to guest signaling by ensuring:
+ * 1. While reading the channel, we disable interrupts from
+ * host.
+ * 2. Ensure that we process all posted messages from the host
+ * before returning from this callback.
+ * 3. Once we return, enable signaling from the host. Once this
+ * state is set we check to see if additional packets are
+ * available to read. In this case we repeat the process.
+ */
+
+ do {
+ hv_begin_read(&channel->inbound);
+ channel->onchannel_callback(arg);
+ bytes_to_read = hv_end_read(&channel->inbound);
+ } while (read_state && (bytes_to_read != 0));
+ } else {
pr_err("no channel callback for relid - %u\n", relid);
+ }
spin_unlock_irqrestore(&channel->inbound_lock, flags);
}
void vmbus_on_event(unsigned long data)
{
u32 dword;
- u32 maxdword = MAX_NUM_CHANNELS_SUPPORTED >> 5;
+ u32 maxdword;
int bit;
u32 relid;
- u32 *recv_int_page = vmbus_connection.recv_int_page;
+ u32 *recv_int_page = NULL;
+ void *page_addr;
+ int cpu = smp_processor_id();
+ union hv_synic_event_flags *event;
+
+ if ((vmbus_proto_version == VERSION_WS2008) ||
+ (vmbus_proto_version == VERSION_WIN7)) {
+ maxdword = MAX_NUM_CHANNELS_SUPPORTED >> 5;
+ recv_int_page = vmbus_connection.recv_int_page;
+ } else {
+ /*
+ * When the host is win8 and beyond, the event page
+ * can be directly checked to get the id of the channel
+ * that has the interrupt pending.
+ */
+ maxdword = HV_EVENT_FLAGS_DWORD_COUNT;
+ page_addr = hv_context.synic_event_page[cpu];
+ event = (union hv_synic_event_flags *)page_addr +
+ VMBUS_MESSAGE_SINT;
+ recv_int_page = event->flags32;
+ }
+
+
/* Check events */
if (!recv_int_page)
/*
* vmbus_set_event - Send an event notification to the parent
*/
-int vmbus_set_event(u32 child_relid)
+int vmbus_set_event(struct vmbus_channel *channel)
{
- /* Each u32 represents 32 channels */
- sync_set_bit(child_relid & 31,
- (unsigned long *)vmbus_connection.send_int_page +
- (child_relid >> 5));
+ u32 child_relid = channel->offermsg.child_relid;
+
+ if (!channel->is_dedicated_interrupt) {
+ /* Each u32 represents 32 channels */
+ sync_set_bit(child_relid & 31,
+ (unsigned long *)vmbus_connection.send_int_page +
+ (child_relid >> 5));
+ }
- return hv_signal_event();
+ return hv_signal_event(channel->sig_event);
}
projects / cascardo / linux.git / blobdiff