diff --git a/drivers/hv/connection.c b/drivers/hv/connection.c index d1019a770ad7..2b56a3f47b30 100644 --- a/drivers/hv/connection.c +++ b/drivers/hv/connection.c @@ -39,16 +39,112 @@ struct vmbus_connection vmbus_connection = { .next_gpadl_handle = ATOMIC_INIT(0xE1E10), }; +/* + * VMBUS version is 32 bit entity broken up into + * two 16 bit quantities: major_number. minor_number. + * + * 0 . 13 (Windows Server 2008) + * 1 . 1 (Windows 7) + * 2 . 4 (Windows 8) + */ + +#define VERSION_WS2008 ((0 << 16) | (13)) +#define VERSION_WIN7 ((1 << 16) | (1)) +#define VERSION_WIN8 ((2 << 16) | (4)) + +#define VERSION_INVAL -1 + +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 { + pr_err("Unable to connect, " + "Version %d not supported by Hyper-V\n", + version); + 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; @@ -99,64 +195,25 @@ int vmbus_connect(void) 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_WS2008; - 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); + do { + ret = vmbus_negotiate_version(msginfo, version); + if (ret == 0) + break; + + version = vmbus_get_next_version(version); + } while (version != VERSION_INVAL); + + if (version == VERSION_INVAL) goto cleanup; - } - - /* 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; - } - - 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; - goto cleanup; - } kfree(msginfo); return 0; diff --git a/include/linux/hyperv.h b/include/linux/hyperv.h index 1ffe84de6c55..b097bf9d9328 100644 --- a/include/linux/hyperv.h +++ b/include/linux/hyperv.h @@ -406,12 +406,6 @@ hv_get_ringbuffer_availbytes(struct hv_ring_buffer_info *rbi, #define HV_DRV_VERSION "3.1" -/* - * A revision number of vmbus that is used for ensuring both ends on a - * partition are using compatible versions. - */ -#define VMBUS_REVISION_NUMBER 13 - /* Make maximum size of pipe payload of 16K */ #define MAX_PIPE_DATA_PAYLOAD (sizeof(u8) * 16384)