diff options
| -rw-r--r-- | arch/x86/include/asm/mshyperv.h | 37 | ||||
| -rw-r--r-- | drivers/hv/channel_mgmt.c | 1 | ||||
| -rw-r--r-- | drivers/hv/hyperv_vmbus.h | 35 |
3 files changed, 38 insertions, 35 deletions
diff --git a/arch/x86/include/asm/mshyperv.h b/arch/x86/include/asm/mshyperv.h index c843ef64defe..b57b470ac2a7 100644 --- a/arch/x86/include/asm/mshyperv.h +++ b/arch/x86/include/asm/mshyperv.h @@ -99,6 +99,43 @@ static inline __u64 generate_guest_id(__u64 d_info1, __u64 kernel_version, return guest_id; } + +/* Free the message slot and signal end-of-message if required */ +static inline void vmbus_signal_eom(struct hv_message *msg, u32 old_msg_type) +{ + /* + * On crash we're reading some other CPU's message page and we need + * to be careful: this other CPU may already had cleared the header + * and the host may already had delivered some other message there. + * In case we blindly write msg->header.message_type we're going + * to lose it. We can still lose a message of the same type but + * we count on the fact that there can only be one + * CHANNELMSG_UNLOAD_RESPONSE and we don't care about other messages + * on crash. + */ + if (cmpxchg(&msg->header.message_type, old_msg_type, + HVMSG_NONE) != old_msg_type) + return; + + /* + * Make sure the write to MessageType (ie set to + * HVMSG_NONE) happens before we read the + * MessagePending and EOMing. Otherwise, the EOMing + * will not deliver any more messages since there is + * no empty slot + */ + mb(); + + if (msg->header.message_flags.msg_pending) { + /* + * This will cause message queue rescan to + * possibly deliver another msg from the + * hypervisor + */ + wrmsrl(HV_X64_MSR_EOM, 0); + } +} + void hyperv_callback_vector(void); #ifdef CONFIG_TRACING #define trace_hyperv_callback_vector hyperv_callback_vector diff --git a/drivers/hv/channel_mgmt.c b/drivers/hv/channel_mgmt.c index 0af7e39006c8..49d77be90ca4 100644 --- a/drivers/hv/channel_mgmt.c +++ b/drivers/hv/channel_mgmt.c @@ -31,6 +31,7 @@ #include <linux/completion.h> #include <linux/delay.h> #include <linux/hyperv.h> +#include <asm/mshyperv.h> #include "hyperv_vmbus.h" diff --git a/drivers/hv/hyperv_vmbus.h b/drivers/hv/hyperv_vmbus.h index 59eb28c45ff5..e9f5d2c2fb6b 100644 --- a/drivers/hv/hyperv_vmbus.h +++ b/drivers/hv/hyperv_vmbus.h @@ -521,41 +521,6 @@ struct vmbus_channel_message_table_entry { extern struct vmbus_channel_message_table_entry channel_message_table[CHANNELMSG_COUNT]; -/* Free the message slot and signal end-of-message if required */ -static inline void vmbus_signal_eom(struct hv_message *msg, u32 old_msg_type) -{ - /* - * On crash we're reading some other CPU's message page and we need - * to be careful: this other CPU may already had cleared the header - * and the host may already had delivered some other message there. - * In case we blindly write msg->header.message_type we're going - * to lose it. We can still lose a message of the same type but - * we count on the fact that there can only be one - * CHANNELMSG_UNLOAD_RESPONSE and we don't care about other messages - * on crash. - */ - if (cmpxchg(&msg->header.message_type, old_msg_type, - HVMSG_NONE) != old_msg_type) - return; - - /* - * Make sure the write to MessageType (ie set to - * HVMSG_NONE) happens before we read the - * MessagePending and EOMing. Otherwise, the EOMing - * will not deliver any more messages since there is - * no empty slot - */ - mb(); - - if (msg->header.message_flags.msg_pending) { - /* - * This will cause message queue rescan to - * possibly deliver another msg from the - * hypervisor - */ - wrmsrl(HV_X64_MSR_EOM, 0); - } -} /* General vmbus interface */ |