From f53335e3289f9ac3a6a8faf6c2f819eee508bd39 Mon Sep 17 00:00:00 2001 From: Dexuan Cui Date: Thu, 5 Sep 2019 23:01:19 +0000 Subject: [PATCH] Drivers: hv: vmbus: Suspend/resume the vmbus itself for hibernation Before Linux enters hibernation, it sends the CHANNELMSG_UNLOAD message to the host so all the offers are gone. After hibernation, Linux needs to re-negotiate with the host using the same vmbus protocol version (which was in use before hibernation), and ask the host to re-offer the vmbus devices. Signed-off-by: Dexuan Cui Reviewed-by: Michael Kelley Signed-off-by: Sasha Levin --- drivers/hv/connection.c | 3 +- drivers/hv/hyperv_vmbus.h | 2 ++ drivers/hv/vmbus_drv.c | 59 +++++++++++++++++++++++++++++++++++++++ 3 files changed, 62 insertions(+), 2 deletions(-) diff --git a/drivers/hv/connection.c b/drivers/hv/connection.c index 09829e15d4a0..806319cd5ccf 100644 --- a/drivers/hv/connection.c +++ b/drivers/hv/connection.c @@ -59,8 +59,7 @@ static __u32 vmbus_get_next_version(__u32 current_version) } } -static int vmbus_negotiate_version(struct vmbus_channel_msginfo *msginfo, - __u32 version) +int vmbus_negotiate_version(struct vmbus_channel_msginfo *msginfo, u32 version) { int ret = 0; unsigned int cur_cpu; diff --git a/drivers/hv/hyperv_vmbus.h b/drivers/hv/hyperv_vmbus.h index 26ea161a6876..e657197a027a 100644 --- a/drivers/hv/hyperv_vmbus.h +++ b/drivers/hv/hyperv_vmbus.h @@ -274,6 +274,8 @@ struct vmbus_msginfo { extern struct vmbus_connection vmbus_connection; +int vmbus_negotiate_version(struct vmbus_channel_msginfo *msginfo, u32 version); + static inline void vmbus_send_interrupt(u32 relid) { sync_set_bit(relid, vmbus_connection.send_int_page); diff --git a/drivers/hv/vmbus_drv.c b/drivers/hv/vmbus_drv.c index a30c70adf9a0..ce9974bf683f 100644 --- a/drivers/hv/vmbus_drv.c +++ b/drivers/hv/vmbus_drv.c @@ -2089,6 +2089,51 @@ acpi_walk_err: return ret_val; } +static int vmbus_bus_suspend(struct device *dev) +{ + vmbus_initiate_unload(false); + + vmbus_connection.conn_state = DISCONNECTED; + + return 0; +} + +static int vmbus_bus_resume(struct device *dev) +{ + struct vmbus_channel_msginfo *msginfo; + size_t msgsize; + int ret; + + /* + * We only use the 'vmbus_proto_version', which was in use before + * hibernation, to re-negotiate with the host. + */ + if (vmbus_proto_version == VERSION_INVAL || + vmbus_proto_version == 0) { + pr_err("Invalid proto version = 0x%x\n", vmbus_proto_version); + return -EINVAL; + } + + msgsize = sizeof(*msginfo) + + sizeof(struct vmbus_channel_initiate_contact); + + msginfo = kzalloc(msgsize, GFP_KERNEL); + + if (msginfo == NULL) + return -ENOMEM; + + ret = vmbus_negotiate_version(msginfo, vmbus_proto_version); + + kfree(msginfo); + + if (ret != 0) + return ret; + + vmbus_request_offers(); + + return 0; +} + static const struct acpi_device_id vmbus_acpi_device_ids[] = { {"VMBUS", 0}, {"VMBus", 0}, @@ -2096,6 +2141,19 @@ static const struct acpi_device_id vmbus_acpi_device_ids[] = { }; MODULE_DEVICE_TABLE(acpi, vmbus_acpi_device_ids); +/* + * Note: we must use SET_NOIRQ_SYSTEM_SLEEP_PM_OPS rather than + * SET_SYSTEM_SLEEP_PM_OPS, otherwise NIC SR-IOV can not work, because the + * "pci_dev_pm_ops" uses the "noirq" callbacks: in the resume path, the + * pci "noirq" restore callback runs before "non-noirq" callbacks (see + * resume_target_kernel() -> dpm_resume_start(), and hibernation_restore() -> + * dpm_resume_end()). This means vmbus_bus_resume() and the pci-hyperv's + * resume callback must also run via the "noirq" callbacks. + */ +static const struct dev_pm_ops vmbus_bus_pm = { + SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(vmbus_bus_suspend, vmbus_bus_resume) +}; + static struct acpi_driver vmbus_acpi_driver = { .name = "vmbus", .ids = vmbus_acpi_device_ids, @@ -2103,6 +2161,7 @@ static struct acpi_driver vmbus_acpi_driver = { .add = vmbus_acpi_add, .remove = vmbus_acpi_remove, }, + .drv.pm = &vmbus_bus_pm, }; static void hv_kexec_handler(void)