From ae20b254306a6a47054ea0eb8444e0bd8e71fe12 Mon Sep 17 00:00:00 2001 From: Dexuan Cui Date: Sat, 12 May 2018 02:30:33 -0700 Subject: [PATCH] Drivers: hv: vmbus: enable VMBus protocol version 5.0 With VMBus protocol 5.0, we're able to better support new features, e.g. running two or more VMBus drivers simultaneously in a single VM -- note: we can't simply load the current VMBus driver twice, instead, a secondary VMBus driver must be implemented. This patch adds the support for the new VMBus protocol, which is available on new Windows hosts, by: 1) We still use SINT2 for compatibility; 2) We must use Connection ID 4 for the Initiate Contact Message, and for subsequent messages, we must use the Message Connection ID field in the host-returned VersionResponse Message. Notes for developers of the secondary VMBus driver: 1) Must use VMBus protocol 5.0 as well; 2) Must use a different SINT number that is not in use. 3) Must use Connection ID 4 for the Initiate Contact Message, and for subsequent messages, must use the Message Connection ID field in the host-returned VersionResponse Message. 4) It's possible that the primary VMBus driver using protocol version 4.0 can work with a secondary VMBus driver using protocol version 5.0, but it's recommended that both should use 5.0 for new Hyper-V features in the future. Signed-off-by: Dexuan Cui Cc: Stephen Hemminger Cc: K. Y. Srinivasan Cc: Michael Kelley Signed-off-by: K. Y. Srinivasan Signed-off-by: Greg Kroah-Hartman --- drivers/hv/connection.c | 44 +++++++++++++++++++++++++++++++++++++-- drivers/hv/hyperv_vmbus.h | 3 +++ include/linux/hyperv.h | 26 +++++++++++++++++++++-- 3 files changed, 69 insertions(+), 4 deletions(-) diff --git a/drivers/hv/connection.c b/drivers/hv/connection.c index 72855182b191..19e046820fda 100644 --- a/drivers/hv/connection.c +++ b/drivers/hv/connection.c @@ -63,6 +63,9 @@ static __u32 vmbus_get_next_version(__u32 current_version) case (VERSION_WIN10): return VERSION_WIN8_1; + case (VERSION_WIN10_V5): + return VERSION_WIN10; + case (VERSION_WS2008): default: return VERSION_INVAL; @@ -80,9 +83,29 @@ static int vmbus_negotiate_version(struct vmbus_channel_msginfo *msginfo, msg = (struct vmbus_channel_initiate_contact *)msginfo->msg; + memset(msg, 0, sizeof(*msg)); msg->header.msgtype = CHANNELMSG_INITIATE_CONTACT; msg->vmbus_version_requested = version; - msg->interrupt_page = virt_to_phys(vmbus_connection.int_page); + + /* + * VMBus protocol 5.0 (VERSION_WIN10_V5) requires that we must use + * VMBUS_MESSAGE_CONNECTION_ID_4 for the Initiate Contact Message, + * and for subsequent messages, we must use the Message Connection ID + * field in the host-returned Version Response Message. And, with + * VERSION_WIN10_V5, we don't use msg->interrupt_page, but we tell + * the host explicitly that we still use VMBUS_MESSAGE_SINT(2) for + * compatibility. + * + * On old hosts, we should always use VMBUS_MESSAGE_CONNECTION_ID (1). + */ + if (version >= VERSION_WIN10_V5) { + msg->msg_sint = VMBUS_MESSAGE_SINT; + vmbus_connection.msg_conn_id = VMBUS_MESSAGE_CONNECTION_ID_4; + } else { + msg->interrupt_page = virt_to_phys(vmbus_connection.int_page); + vmbus_connection.msg_conn_id = VMBUS_MESSAGE_CONNECTION_ID; + } + msg->monitor_page1 = virt_to_phys(vmbus_connection.monitor_pages[0]); msg->monitor_page2 = virt_to_phys(vmbus_connection.monitor_pages[1]); /* @@ -137,6 +160,10 @@ static int vmbus_negotiate_version(struct vmbus_channel_msginfo *msginfo, /* Check if successful */ if (msginfo->response.version_response.version_supported) { vmbus_connection.conn_state = CONNECTED; + + if (version >= VERSION_WIN10_V5) + vmbus_connection.msg_conn_id = + msginfo->response.version_response.msg_conn_id; } else { return -ECONNREFUSED; } @@ -354,13 +381,14 @@ void vmbus_on_event(unsigned long data) */ int vmbus_post_msg(void *buffer, size_t buflen, bool can_sleep) { + struct vmbus_channel_message_header *hdr; union hv_connection_id conn_id; int ret = 0; int retries = 0; u32 usec = 1; conn_id.asu32 = 0; - conn_id.u.id = VMBUS_MESSAGE_CONNECTION_ID; + conn_id.u.id = vmbus_connection.msg_conn_id; /* * hv_post_message() can have transient failures because of @@ -372,6 +400,18 @@ int vmbus_post_msg(void *buffer, size_t buflen, bool can_sleep) switch (ret) { case HV_STATUS_INVALID_CONNECTION_ID: + /* + * See vmbus_negotiate_version(): VMBus protocol 5.0 + * requires that we must use + * VMBUS_MESSAGE_CONNECTION_ID_4 for the Initiate + * Contact message, but on old hosts that only + * support VMBus protocol 4.0 or lower, here we get + * HV_STATUS_INVALID_CONNECTION_ID and we should + * return an error immediately without retrying. + */ + hdr = (struct vmbus_channel_message_header *)buffer; + if (hdr->msgtype == CHANNELMSG_INITIATE_CONTACT) + return -EINVAL; /* * We could get this if we send messages too * frequently. diff --git a/drivers/hv/hyperv_vmbus.h b/drivers/hv/hyperv_vmbus.h index f761bef36e77..72eaba3d50fc 100644 --- a/drivers/hv/hyperv_vmbus.h +++ b/drivers/hv/hyperv_vmbus.h @@ -187,6 +187,7 @@ struct hv_input_post_message { enum { VMBUS_MESSAGE_CONNECTION_ID = 1, + VMBUS_MESSAGE_CONNECTION_ID_4 = 4, VMBUS_MESSAGE_PORT_ID = 1, VMBUS_EVENT_CONNECTION_ID = 2, VMBUS_EVENT_PORT_ID = 2, @@ -302,6 +303,8 @@ struct vmbus_connection { */ int connect_cpu; + u32 msg_conn_id; + atomic_t offer_in_progress; enum vmbus_connect_state conn_state; diff --git a/include/linux/hyperv.h b/include/linux/hyperv.h index 192ed8fbc403..11b5612dc066 100644 --- a/include/linux/hyperv.h +++ b/include/linux/hyperv.h @@ -163,6 +163,7 @@ static inline u32 hv_get_bytes_to_write(const struct hv_ring_buffer_info *rbi) * 2 . 4 (Windows 8) * 3 . 0 (Windows 8 R2) * 4 . 0 (Windows 10) + * 5 . 0 (Newer Windows 10) */ #define VERSION_WS2008 ((0 << 16) | (13)) @@ -170,10 +171,11 @@ static inline u32 hv_get_bytes_to_write(const struct hv_ring_buffer_info *rbi) #define VERSION_WIN8 ((2 << 16) | (4)) #define VERSION_WIN8_1 ((3 << 16) | (0)) #define VERSION_WIN10 ((4 << 16) | (0)) +#define VERSION_WIN10_V5 ((5 << 16) | (0)) #define VERSION_INVAL -1 -#define VERSION_CURRENT VERSION_WIN10 +#define VERSION_CURRENT VERSION_WIN10_V5 /* Make maximum size of pipe payload of 16K */ #define MAX_PIPE_DATA_PAYLOAD (sizeof(u8) * 16384) @@ -570,7 +572,14 @@ struct vmbus_channel_initiate_contact { struct vmbus_channel_message_header header; u32 vmbus_version_requested; u32 target_vcpu; /* The VCPU the host should respond to */ - u64 interrupt_page; + union { + u64 interrupt_page; + struct { + u8 msg_sint; + u8 padding1[3]; + u32 padding2; + }; + }; u64 monitor_page1; u64 monitor_page2; } __packed; @@ -585,6 +594,19 @@ struct vmbus_channel_tl_connect_request { struct vmbus_channel_version_response { struct vmbus_channel_message_header header; u8 version_supported; + + u8 connection_state; + u16 padding; + + /* + * On new hosts that support VMBus protocol 5.0, we must use + * VMBUS_MESSAGE_CONNECTION_ID_4 for the Initiate Contact Message, + * and for subsequent messages, we must use the Message Connection ID + * field in the host-returned Version Response Message. + * + * On old hosts, we should always use VMBUS_MESSAGE_CONNECTION_ID (1). + */ + u32 msg_conn_id; } __packed; enum vmbus_channel_state {