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authorStefano Garzarella <sgarzare@redhat.com>2019-11-14 10:57:47 +0100
committerDavid S. Miller <davem@davemloft.net>2019-11-14 18:12:18 -0800
commitb1bba80a4376aef34de2b57bfb8834bd095703ed (patch)
treeb22280bc8b8e0f8789bfeb7f4013e0c670be2ca4 /drivers/misc
parentc0cfa2d8a788fcf45df5bf4070ab2474c88d543a (diff)
downloadlinux-b1bba80a4376aef34de2b57bfb8834bd095703ed.tar.bz2
vsock/vmci: register vmci_transport only when VMCI guest/host are active
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 <jhansen@vmware.com> Signed-off-by: Stefano Garzarella <sgarzare@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'drivers/misc')
-rw-r--r--drivers/misc/vmw_vmci/vmci_driver.c67
-rw-r--r--drivers/misc/vmw_vmci/vmci_driver.h2
-rw-r--r--drivers/misc/vmw_vmci/vmci_guest.c2
-rw-r--r--drivers/misc/vmw_vmci/vmci_host.c7
4 files changed, 78 insertions, 0 deletions
diff --git a/drivers/misc/vmw_vmci/vmci_driver.c b/drivers/misc/vmw_vmci/vmci_driver.c
index 819e35995d32..95fed4664a2d 100644
--- a/drivers/misc/vmw_vmci/vmci_driver.c
+++ b/drivers/misc/vmw_vmci/vmci_driver.c
@@ -28,6 +28,10 @@ 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.
*
@@ -45,6 +49,69 @@ 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 aab81b67670c..990682480bf6 100644
--- a/drivers/misc/vmw_vmci/vmci_driver.h
+++ b/drivers/misc/vmw_vmci/vmci_driver.h
@@ -36,10 +36,12 @@ 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 7a84a48c75da..cc8eeb361fcd 100644
--- a/drivers/misc/vmw_vmci/vmci_guest.c
+++ b/drivers/misc/vmw_vmci/vmci_guest.c
@@ -637,6 +637,8 @@ 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 833e2bd248a5..ff3c396146ff 100644
--- a/drivers/misc/vmw_vmci/vmci_host.c
+++ b/drivers/misc/vmw_vmci/vmci_host.c
@@ -108,6 +108,11 @@ 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.
*/
@@ -338,6 +343,8 @@ 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: