From: Stefano Garzarella <sgarz...@redhat.com> To allow other transports to be loaded with vmci_transport, we register the vmci_transport as G2H or H2G only when a VMCI guest or host is active.
To do that, this patch adds a callback registered in the vmci driver that will be called when the host or guest becomes active. This callback will register the vmci_transport in the VSOCK core. Cc: Jorgen Hansen <jhan...@vmware.com> Signed-off-by: Stefano Garzarella <sgarz...@redhat.com> Signed-off-by: David S. Miller <da...@davemloft.net> https://jira.sw.ru/browse/PSBM-128702 (cherry picked from commit b1bba80a4376aef34de2b57bfb8834bd095703ed) Signed-off-by: Konstantin Khorenko <khore...@virtuozzo.com> --- drivers/misc/vmw_vmci/vmci_driver.c | 67 +++++++++++++++++++++++++++++ drivers/misc/vmw_vmci/vmci_driver.h | 2 + drivers/misc/vmw_vmci/vmci_guest.c | 2 + drivers/misc/vmw_vmci/vmci_host.c | 7 +++ include/linux/vmw_vmci_api.h | 2 + net/vmw_vsock/vmci_transport.c | 33 +++++++++----- 6 files changed, 102 insertions(+), 11 deletions(-) diff --git a/drivers/misc/vmw_vmci/vmci_driver.c b/drivers/misc/vmw_vmci/vmci_driver.c index 003bfba40758..64e540cfb749 100644 --- a/drivers/misc/vmw_vmci/vmci_driver.c +++ b/drivers/misc/vmw_vmci/vmci_driver.c @@ -36,6 +36,10 @@ MODULE_PARM_DESC(disable_guest, static bool vmci_guest_personality_initialized; static bool vmci_host_personality_initialized; +static DEFINE_MUTEX(vmci_vsock_mutex); /* protects vmci_vsock_transport_cb */ +static vmci_vsock_cb vmci_vsock_transport_cb; +bool vmci_vsock_cb_host_called; + /* * vmci_get_context_id() - Gets the current context ID. * @@ -53,6 +57,69 @@ u32 vmci_get_context_id(void) } EXPORT_SYMBOL_GPL(vmci_get_context_id); +/* + * vmci_register_vsock_callback() - Register the VSOCK vmci_transport callback. + * + * The callback will be called when the first host or guest becomes active, + * or if they are already active when this function is called. + * To unregister the callback, call this function with NULL parameter. + * + * Returns 0 on success. -EBUSY if a callback is already registered. + */ +int vmci_register_vsock_callback(vmci_vsock_cb callback) +{ + int err = 0; + + mutex_lock(&vmci_vsock_mutex); + + if (vmci_vsock_transport_cb && callback) { + err = -EBUSY; + goto out; + } + + vmci_vsock_transport_cb = callback; + + if (!vmci_vsock_transport_cb) { + vmci_vsock_cb_host_called = false; + goto out; + } + + if (vmci_guest_code_active()) + vmci_vsock_transport_cb(false); + + if (vmci_host_users() > 0) { + vmci_vsock_cb_host_called = true; + vmci_vsock_transport_cb(true); + } + +out: + mutex_unlock(&vmci_vsock_mutex); + return err; +} +EXPORT_SYMBOL_GPL(vmci_register_vsock_callback); + +void vmci_call_vsock_callback(bool is_host) +{ + mutex_lock(&vmci_vsock_mutex); + + if (!vmci_vsock_transport_cb) + goto out; + + /* In the host, this function could be called multiple times, + * but we want to register it only once. + */ + if (is_host) { + if (vmci_vsock_cb_host_called) + goto out; + + vmci_vsock_cb_host_called = true; + } + + vmci_vsock_transport_cb(is_host); +out: + mutex_unlock(&vmci_vsock_mutex); +} + static int __init vmci_drv_init(void) { int vmci_err; diff --git a/drivers/misc/vmw_vmci/vmci_driver.h b/drivers/misc/vmw_vmci/vmci_driver.h index cee9e977d318..8bc7806f552e 100644 --- a/drivers/misc/vmw_vmci/vmci_driver.h +++ b/drivers/misc/vmw_vmci/vmci_driver.h @@ -44,10 +44,12 @@ extern struct pci_dev *vmci_pdev; u32 vmci_get_context_id(void); int vmci_send_datagram(struct vmci_datagram *dg); +void vmci_call_vsock_callback(bool is_host); int vmci_host_init(void); void vmci_host_exit(void); bool vmci_host_code_active(void); +int vmci_host_users(void); int vmci_guest_init(void); void vmci_guest_exit(void); diff --git a/drivers/misc/vmw_vmci/vmci_guest.c b/drivers/misc/vmw_vmci/vmci_guest.c index c2ea93778b50..7c8c2652d4cd 100644 --- a/drivers/misc/vmw_vmci/vmci_guest.c +++ b/drivers/misc/vmw_vmci/vmci_guest.c @@ -647,6 +647,8 @@ static int vmci_guest_probe_device(struct pci_dev *pdev, vmci_dev->iobase + VMCI_CONTROL_ADDR); pci_set_drvdata(pdev, vmci_dev); + + vmci_call_vsock_callback(false); return 0; err_free_irq: diff --git a/drivers/misc/vmw_vmci/vmci_host.c b/drivers/misc/vmw_vmci/vmci_host.c index a721b5d8a9da..dec56cf914db 100644 --- a/drivers/misc/vmw_vmci/vmci_host.c +++ b/drivers/misc/vmw_vmci/vmci_host.c @@ -116,6 +116,11 @@ bool vmci_host_code_active(void) atomic_read(&vmci_host_active_users) > 0); } +int vmci_host_users(void) +{ + return atomic_read(&vmci_host_active_users); +} + /* * Called on open of /dev/vmci. */ @@ -346,6 +351,8 @@ static int vmci_host_do_init_context(struct vmci_host_dev *vmci_host_dev, vmci_host_dev->ct_type = VMCIOBJ_CONTEXT; atomic_inc(&vmci_host_active_users); + vmci_call_vsock_callback(true); + retval = 0; out: diff --git a/include/linux/vmw_vmci_api.h b/include/linux/vmw_vmci_api.h index 023430e265fe..73df207e67e1 100644 --- a/include/linux/vmw_vmci_api.h +++ b/include/linux/vmw_vmci_api.h @@ -26,6 +26,7 @@ typedef void (vmci_device_shutdown_fn) (void *device_registration, void *user_data); +typedef void (*vmci_vsock_cb) (bool is_host); int vmci_datagram_create_handle(u32 resource_id, u32 flags, vmci_datagram_recv_cb recv_cb, @@ -44,6 +45,7 @@ int vmci_doorbell_destroy(struct vmci_handle handle); int vmci_doorbell_notify(struct vmci_handle handle, u32 priv_flags); u32 vmci_get_context_id(void); bool vmci_is_context_owner(u32 context_id, kuid_t uid); +int vmci_register_vsock_callback(vmci_vsock_cb callback); int vmci_event_subscribe(u32 event, vmci_event_cb callback, void *callback_data, diff --git a/net/vmw_vsock/vmci_transport.c b/net/vmw_vsock/vmci_transport.c index 97055652038e..ff9741932abb 100644 --- a/net/vmw_vsock/vmci_transport.c +++ b/net/vmw_vsock/vmci_transport.c @@ -2033,19 +2033,21 @@ static bool vmci_check_transport(struct vsock_sock *vsk) return vsk->transport == &vmci_transport; } -static int __init vmci_transport_init(void) +void vmci_vsock_transport_cb(bool is_host) { - int features = VSOCK_TRANSPORT_F_DGRAM | VSOCK_TRANSPORT_F_H2G; - int cid; - int err; + int features; - cid = vmci_get_context_id(); + if (is_host) + features = VSOCK_TRANSPORT_F_H2G; + else + features = VSOCK_TRANSPORT_F_G2H; - if (cid == VMCI_INVALID_ID) - return -EINVAL; + vsock_core_register(&vmci_transport, features); +} - if (cid != VMCI_HOST_CONTEXT_ID) - features |= VSOCK_TRANSPORT_F_G2H; +static int __init vmci_transport_init(void) +{ + int err; /* Create the datagram handle that we will use to send and receive all * VSocket control messages for this context. @@ -2059,7 +2061,6 @@ static int __init vmci_transport_init(void) pr_err("Unable to create datagram handle. (%d)\n", err); return vmci_transport_error_to_vsock_error(err); } - err = vmci_event_subscribe(VMCI_EVENT_QP_RESUMED, vmci_transport_qp_resumed_cb, NULL, &vmci_transport_qp_resumed_sub_id); @@ -2070,12 +2071,21 @@ static int __init vmci_transport_init(void) goto err_destroy_stream_handle; } - err = vsock_core_register(&vmci_transport, features); + /* Register only with dgram feature, other features (H2G, G2H) will be + * registered when the first host or guest becomes active. + */ + err = vsock_core_register(&vmci_transport, VSOCK_TRANSPORT_F_DGRAM); if (err < 0) goto err_unsubscribe; + err = vmci_register_vsock_callback(vmci_vsock_transport_cb); + if (err < 0) + goto err_unregister; + return 0; +err_unregister: + vsock_core_unregister(&vmci_transport); err_unsubscribe: vmci_event_unsubscribe(vmci_transport_qp_resumed_sub_id); err_destroy_stream_handle: @@ -2101,6 +2111,7 @@ static void __exit vmci_transport_exit(void) vmci_transport_qp_resumed_sub_id = VMCI_INVALID_ID; } + vmci_register_vsock_callback(NULL); vsock_core_unregister(&vmci_transport); } module_exit(vmci_transport_exit); -- 2.24.3 _______________________________________________ Devel mailing list Devel@openvz.org https://lists.openvz.org/mailman/listinfo/devel
