USB: make usbdevices export their device nodes instead of using a separate class
o The "real" usb-devices export now a device node which can
populate /dev/bus/usb.
o The usb_device class is optional now and can be disabled in the
kernel config. Major/minor of the "real" devices and class devices
are the same.
o The environment of the usb-device event contains DEVNUM and BUSNUM to
help udev and get rid of the ugly udev rule we need for the class
devices.
o The usb-devices and usb-interfaces share the same bus, so I used
the new "struct device_type" to let these devices identify
themselves. This also removes the current logic of using a magic
platform-pointer.
The name of the device_type is also added to the environment
which makes it easier to distinguish the different kinds of devices
on the same subsystem.
It looks like this:
add@/devices/pci0000:00/0000:00:1d.1/usb2/2-1
ACTION=add
DEVPATH=/devices/pci0000:00/0000:00:1d.1/usb2/2-1
SUBSYSTEM=usb
SEQNUM=1533
MAJOR=189
MINOR=131
DEVTYPE=usb_device
PRODUCT=46d/c03e/2000
TYPE=0/0/0
BUSNUM=002
DEVNUM=004
This udev rule works as a replacement for usb_device class devices:
SUBSYSTEM=="usb", ACTION=="add", ENV{DEVTYPE}=="usb_device", \
NAME="bus/usb/$env{BUSNUM}/$env{DEVNUM}", MODE="0644"
Updated patch, which needs the device_type patches in Greg's tree.
I also got a bugzilla assigned for this. :)
https://bugzilla.novell.com/show_bug.cgi?id=250659
Signed-off-by: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
diff --git a/drivers/usb/core/Kconfig b/drivers/usb/core/Kconfig
index 2fc0f88..f493fb1 100644
--- a/drivers/usb/core/Kconfig
+++ b/drivers/usb/core/Kconfig
@@ -31,7 +31,30 @@
For the format of the various /proc/bus/usb/ files, please read
<file:Documentation/usb/proc_usb_info.txt>.
- Most users want to say Y here.
+ Usbfs files can't handle Access Control Lists (ACL), which are the
+ default way to grant access to USB devices for untrusted users of a
+ desktop system. The usbfs functionality is replaced by real
+ device-nodes managed by udev. These nodes live in /dev/bus/usb and
+ are used by libusb.
+
+config USB_DEVICE_CLASS
+ bool "USB device class-devices (DEPRECATED)"
+ depends on USB
+ default n
+ ---help---
+ Userspace access to USB devices is granted by device-nodes exported
+ directly from the usbdev in sysfs. Old versions of the driver
+ core and udev needed additional class devices to export device nodes.
+
+ These additional devices are difficult to handle in userspace, if
+ information about USB interfaces must be available. One device contains
+ the device node, the other device contains the interface data. Both
+ devices are at the same level in sysfs (siblings) and one can't access
+ the other. The device node created directly by the usbdev is the parent
+ device of the interface and therefore easily accessible from the interface
+ event.
+
+ This option provides backward compatibility if needed.
config USB_DYNAMIC_MINORS
bool "Dynamic USB minor allocation (EXPERIMENTAL)"
diff --git a/drivers/usb/core/devio.c b/drivers/usb/core/devio.c
index fc3545d..e023f3d 100644
--- a/drivers/usb/core/devio.c
+++ b/drivers/usb/core/devio.c
@@ -57,7 +57,6 @@
#define USB_MAXBUS 64
#define USB_DEVICE_MAX USB_MAXBUS * 128
-static struct class *usb_device_class;
/* Mutual exclusion for removal, open, and release */
DEFINE_MUTEX(usbfs_mutex);
@@ -514,22 +513,25 @@
return ret;
}
-static struct usb_device *usbdev_lookup_minor(int minor)
+static int __match_minor(struct device *dev, void *data)
{
- struct device *device;
- struct usb_device *udev = NULL;
+ int minor = *((int *)data);
- down(&usb_device_class->sem);
- list_for_each_entry(device, &usb_device_class->devices, node) {
- if (device->devt == MKDEV(USB_DEVICE_MAJOR, minor)) {
- udev = device->platform_data;
- break;
- }
- }
- up(&usb_device_class->sem);
+ if (dev->devt == MKDEV(USB_DEVICE_MAJOR, minor))
+ return 1;
+ return 0;
+}
- return udev;
-};
+static struct usb_device *usbdev_lookup_by_minor(int minor)
+{
+ struct device *dev;
+
+ dev = bus_find_device(&usb_bus_type, NULL, &minor, __match_minor);
+ if (!dev)
+ return NULL;
+ put_device(dev);
+ return container_of(dev, struct usb_device, dev);
+}
/*
* file operations
@@ -548,11 +550,14 @@
goto out;
ret = -ENOENT;
- /* check if we are called from a real node or usbfs */
+ /* usbdev device-node */
if (imajor(inode) == USB_DEVICE_MAJOR)
- dev = usbdev_lookup_minor(iminor(inode));
+ dev = usbdev_lookup_by_minor(iminor(inode));
+#ifdef CONFIG_USB_DEVICEFS
+ /* procfs file */
if (!dev)
dev = inode->i_private;
+#endif
if (!dev)
goto out;
ret = usb_autoresume_device(dev);
@@ -1570,7 +1575,7 @@
return mask;
}
-const struct file_operations usbfs_device_file_operations = {
+const struct file_operations usbdev_file_operations = {
.llseek = usbdev_lseek,
.read = usbdev_read,
.poll = usbdev_poll,
@@ -1579,50 +1584,53 @@
.release = usbdev_release,
};
-static int usbdev_add(struct usb_device *dev)
+#ifdef CONFIG_USB_DEVICE_CLASS
+static struct class *usb_classdev_class;
+
+static int usb_classdev_add(struct usb_device *dev)
{
int minor = ((dev->bus->busnum-1) * 128) + (dev->devnum-1);
- dev->usbfs_dev = device_create(usb_device_class, &dev->dev,
+ dev->usb_classdev = device_create(usb_classdev_class, &dev->dev,
MKDEV(USB_DEVICE_MAJOR, minor),
"usbdev%d.%d", dev->bus->busnum, dev->devnum);
- if (IS_ERR(dev->usbfs_dev))
- return PTR_ERR(dev->usbfs_dev);
+ if (IS_ERR(dev->usb_classdev))
+ return PTR_ERR(dev->usb_classdev);
- dev->usbfs_dev->platform_data = dev;
return 0;
}
-static void usbdev_remove(struct usb_device *dev)
+static void usb_classdev_remove(struct usb_device *dev)
{
- device_unregister(dev->usbfs_dev);
+ device_unregister(dev->usb_classdev);
}
-static int usbdev_notify(struct notifier_block *self, unsigned long action,
- void *dev)
+static int usb_classdev_notify(struct notifier_block *self,
+ unsigned long action, void *dev)
{
switch (action) {
case USB_DEVICE_ADD:
- if (usbdev_add(dev))
+ if (usb_classdev_add(dev))
return NOTIFY_BAD;
break;
case USB_DEVICE_REMOVE:
- usbdev_remove(dev);
+ usb_classdev_remove(dev);
break;
}
return NOTIFY_OK;
}
static struct notifier_block usbdev_nb = {
- .notifier_call = usbdev_notify,
+ .notifier_call = usb_classdev_notify,
};
+#endif
static struct cdev usb_device_cdev = {
.kobj = {.name = "usb_device", },
.owner = THIS_MODULE,
};
-int __init usbdev_init(void)
+int __init usb_devio_init(void)
{
int retval;
@@ -1632,38 +1640,38 @@
err("unable to register minors for usb_device");
goto out;
}
- cdev_init(&usb_device_cdev, &usbfs_device_file_operations);
+ cdev_init(&usb_device_cdev, &usbdev_file_operations);
retval = cdev_add(&usb_device_cdev, USB_DEVICE_DEV, USB_DEVICE_MAX);
if (retval) {
err("unable to get usb_device major %d", USB_DEVICE_MAJOR);
goto error_cdev;
}
- usb_device_class = class_create(THIS_MODULE, "usb_device");
- if (IS_ERR(usb_device_class)) {
+#ifdef CONFIG_USB_DEVICE_CLASS
+ usb_classdev_class = class_create(THIS_MODULE, "usb_device");
+ if (IS_ERR(usb_classdev_class)) {
err("unable to register usb_device class");
- retval = PTR_ERR(usb_device_class);
- goto error_class;
+ retval = PTR_ERR(usb_classdev_class);
+ cdev_del(&usb_device_cdev);
+ usb_classdev_class = NULL;
+ goto out;
}
usb_register_notify(&usbdev_nb);
-
+#endif
out:
return retval;
-error_class:
- usb_device_class = NULL;
- cdev_del(&usb_device_cdev);
-
error_cdev:
unregister_chrdev_region(USB_DEVICE_DEV, USB_DEVICE_MAX);
goto out;
}
-void usbdev_cleanup(void)
+void usb_devio_cleanup(void)
{
+#ifdef CONFIG_USB_DEVICE_CLASS
usb_unregister_notify(&usbdev_nb);
- class_destroy(usb_device_class);
+ class_destroy(usb_classdev_class);
+#endif
cdev_del(&usb_device_cdev);
unregister_chrdev_region(USB_DEVICE_DEV, USB_DEVICE_MAX);
}
-
diff --git a/drivers/usb/core/driver.c b/drivers/usb/core/driver.c
index 9b6a60f..593386e 100644
--- a/drivers/usb/core/driver.c
+++ b/drivers/usb/core/driver.c
@@ -574,23 +574,10 @@
}
#ifdef CONFIG_HOTPLUG
-
-/*
- * This sends an uevent to userspace, typically helping to load driver
- * or other modules, configure the device, and more. Drivers can provide
- * a MODULE_DEVICE_TABLE to help with module loading subtasks.
- *
- * We're called either from khubd (the typical case) or from root hub
- * (init, kapmd, modprobe, rmmod, etc), but the agents need to handle
- * delays in event delivery. Use sysfs (and DEVPATH) to make sure the
- * device (and this configuration!) are still present.
- */
static int usb_uevent(struct device *dev, char **envp, int num_envp,
char *buffer, int buffer_size)
{
- struct usb_interface *intf;
struct usb_device *usb_dev;
- struct usb_host_interface *alt;
int i = 0;
int length = 0;
@@ -600,13 +587,11 @@
/* driver is often null here; dev_dbg() would oops */
pr_debug ("usb %s: uevent\n", dev->bus_id);
- if (is_usb_device(dev)) {
+ if (is_usb_device(dev))
usb_dev = to_usb_device(dev);
- alt = NULL;
- } else {
- intf = to_usb_interface(dev);
+ else {
+ struct usb_interface *intf = to_usb_interface(dev);
usb_dev = interface_to_usbdev(intf);
- alt = intf->cur_altsetting;
}
if (usb_dev->devnum < 0) {
@@ -621,9 +606,7 @@
#ifdef CONFIG_USB_DEVICEFS
/* If this is available, userspace programs can directly read
* all the device descriptors we don't tell them about. Or
- * even act as usermode drivers.
- *
- * FIXME reduce hardwired intelligence here
+ * act as usermode drivers.
*/
if (add_uevent_var(envp, num_envp, &i,
buffer, buffer_size, &length,
@@ -650,44 +633,29 @@
usb_dev->descriptor.bDeviceProtocol))
return -ENOMEM;
- if (!is_usb_device(dev)) {
-
- if (add_uevent_var(envp, num_envp, &i,
+ if (add_uevent_var(envp, num_envp, &i,
buffer, buffer_size, &length,
- "INTERFACE=%d/%d/%d",
- alt->desc.bInterfaceClass,
- alt->desc.bInterfaceSubClass,
- alt->desc.bInterfaceProtocol))
- return -ENOMEM;
+ "BUSNUM=%03d",
+ usb_dev->bus->busnum))
+ return -ENOMEM;
- if (add_uevent_var(envp, num_envp, &i,
+ if (add_uevent_var(envp, num_envp, &i,
buffer, buffer_size, &length,
- "MODALIAS=usb:v%04Xp%04Xd%04Xdc%02Xdsc%02Xdp%02Xic%02Xisc%02Xip%02X",
- le16_to_cpu(usb_dev->descriptor.idVendor),
- le16_to_cpu(usb_dev->descriptor.idProduct),
- le16_to_cpu(usb_dev->descriptor.bcdDevice),
- usb_dev->descriptor.bDeviceClass,
- usb_dev->descriptor.bDeviceSubClass,
- usb_dev->descriptor.bDeviceProtocol,
- alt->desc.bInterfaceClass,
- alt->desc.bInterfaceSubClass,
- alt->desc.bInterfaceProtocol))
- return -ENOMEM;
- }
+ "DEVNUM=%03d",
+ usb_dev->devnum))
+ return -ENOMEM;
envp[i] = NULL;
-
return 0;
}
#else
static int usb_uevent(struct device *dev, char **envp,
- int num_envp, char *buffer, int buffer_size)
+ int num_envp, char *buffer, int buffer_size)
{
return -ENODEV;
}
-
#endif /* CONFIG_HOTPLUG */
/**
diff --git a/drivers/usb/core/hub.c b/drivers/usb/core/hub.c
index 19abe81..2a0b15e 100644
--- a/drivers/usb/core/hub.c
+++ b/drivers/usb/core/hub.c
@@ -1367,11 +1367,15 @@
}
#endif
+ /* export the usbdev device-node for libusb */
+ udev->dev.devt = MKDEV(USB_DEVICE_MAJOR,
+ (((udev->bus->busnum-1) * 128) + (udev->devnum-1)));
+
/* Register the device. The device driver is responsible
- * for adding the device files to usbfs and sysfs and for
- * configuring the device.
+ * for adding the device files to sysfs and for configuring
+ * the device.
*/
- err = device_add (&udev->dev);
+ err = device_add(&udev->dev);
if (err) {
dev_err(&udev->dev, "can't device_add, error %d\n", err);
goto fail;
diff --git a/drivers/usb/core/inode.c b/drivers/usb/core/inode.c
index 11dad22..cddfc62 100644
--- a/drivers/usb/core/inode.c
+++ b/drivers/usb/core/inode.c
@@ -662,7 +662,7 @@
sprintf (name, "%03d", dev->devnum);
dev->usbfs_dentry = fs_create_file (name, devmode | S_IFREG,
dev->bus->usbfs_dentry, dev,
- &usbfs_device_file_operations,
+ &usbdev_file_operations,
devuid, devgid);
if (dev->usbfs_dentry == NULL) {
err ("error creating usbfs device entry");
diff --git a/drivers/usb/core/message.c b/drivers/usb/core/message.c
index c359ccb..da4ee07 100644
--- a/drivers/usb/core/message.c
+++ b/drivers/usb/core/message.c
@@ -1305,7 +1305,7 @@
return 0;
}
-static void release_interface(struct device *dev)
+void usb_release_interface(struct device *dev)
{
struct usb_interface *intf = to_usb_interface(dev);
struct usb_interface_cache *intfc =
@@ -1315,6 +1315,67 @@
kfree(intf);
}
+#ifdef CONFIG_HOTPLUG
+static int usb_if_uevent(struct device *dev, char **envp, int num_envp,
+ char *buffer, int buffer_size)
+{
+ struct usb_device *usb_dev;
+ struct usb_interface *intf;
+ struct usb_host_interface *alt;
+ int i = 0;
+ int length = 0;
+
+ if (!dev)
+ return -ENODEV;
+
+ /* driver is often null here; dev_dbg() would oops */
+ pr_debug ("usb %s: uevent\n", dev->bus_id);
+
+ intf = to_usb_interface(dev);
+ usb_dev = interface_to_usbdev(intf);
+ alt = intf->cur_altsetting;
+
+ if (add_uevent_var(envp, num_envp, &i,
+ buffer, buffer_size, &length,
+ "INTERFACE=%d/%d/%d",
+ alt->desc.bInterfaceClass,
+ alt->desc.bInterfaceSubClass,
+ alt->desc.bInterfaceProtocol))
+ return -ENOMEM;
+
+ if (add_uevent_var(envp, num_envp, &i,
+ buffer, buffer_size, &length,
+ "MODALIAS=usb:v%04Xp%04Xd%04Xdc%02Xdsc%02Xdp%02Xic%02Xisc%02Xip%02X",
+ le16_to_cpu(usb_dev->descriptor.idVendor),
+ le16_to_cpu(usb_dev->descriptor.idProduct),
+ le16_to_cpu(usb_dev->descriptor.bcdDevice),
+ usb_dev->descriptor.bDeviceClass,
+ usb_dev->descriptor.bDeviceSubClass,
+ usb_dev->descriptor.bDeviceProtocol,
+ alt->desc.bInterfaceClass,
+ alt->desc.bInterfaceSubClass,
+ alt->desc.bInterfaceProtocol))
+ return -ENOMEM;
+
+ envp[i] = NULL;
+ return 0;
+}
+
+#else
+
+static int usb_if_uevent(struct device *dev, char **envp,
+ int num_envp, char *buffer, int buffer_size)
+{
+ return -ENODEV;
+}
+#endif /* CONFIG_HOTPLUG */
+
+struct device_type usb_if_device_type = {
+ .name = "usb_interface",
+ .release = usb_release_interface,
+ .uevent = usb_if_uevent,
+};
+
/*
* usb_set_configuration - Makes a particular device setting be current
* @dev: the device whose configuration is being updated
@@ -1478,8 +1539,8 @@
intf->dev.parent = &dev->dev;
intf->dev.driver = NULL;
intf->dev.bus = &usb_bus_type;
+ intf->dev.type = &usb_if_device_type;
intf->dev.dma_mask = dev->dev.dma_mask;
- intf->dev.release = release_interface;
device_initialize (&intf->dev);
mark_quiesced(intf);
sprintf (&intf->dev.bus_id[0], "%d-%s:%d.%d",
diff --git a/drivers/usb/core/usb.c b/drivers/usb/core/usb.c
index 6f35dce..dfd1b5c 100644
--- a/drivers/usb/core/usb.c
+++ b/drivers/usb/core/usb.c
@@ -197,6 +197,11 @@
kfree(udev);
}
+struct device_type usb_device_type = {
+ .name = "usb_device",
+ .release = usb_release_dev,
+};
+
#ifdef CONFIG_PM
static int ksuspend_usb_init(void)
@@ -247,13 +252,10 @@
device_initialize(&dev->dev);
dev->dev.bus = &usb_bus_type;
+ dev->dev.type = &usb_device_type;
dev->dev.dma_mask = bus->controller->dma_mask;
- dev->dev.release = usb_release_dev;
dev->state = USB_STATE_ATTACHED;
- /* This magic assignment distinguishes devices from interfaces */
- dev->dev.platform_data = &usb_generic_driver;
-
INIT_LIST_HEAD(&dev->ep0.urb_list);
dev->ep0.desc.bLength = USB_DT_ENDPOINT_SIZE;
dev->ep0.desc.bDescriptorType = USB_DT_ENDPOINT;
@@ -882,9 +884,9 @@
retval = usb_register(&usbfs_driver);
if (retval)
goto driver_register_failed;
- retval = usbdev_init();
+ retval = usb_devio_init();
if (retval)
- goto usbdevice_init_failed;
+ goto usb_devio_init_failed;
retval = usbfs_init();
if (retval)
goto fs_init_failed;
@@ -899,8 +901,8 @@
hub_init_failed:
usbfs_cleanup();
fs_init_failed:
- usbdev_cleanup();
-usbdevice_init_failed:
+ usb_devio_cleanup();
+usb_devio_init_failed:
usb_deregister(&usbfs_driver);
driver_register_failed:
usb_major_cleanup();
@@ -927,7 +929,7 @@
usb_major_cleanup();
usbfs_cleanup();
usb_deregister(&usbfs_driver);
- usbdev_cleanup();
+ usb_devio_cleanup();
usb_hub_cleanup();
usb_host_cleanup();
bus_unregister(&usb_bus_type);
diff --git a/drivers/usb/core/usb.h b/drivers/usb/core/usb.h
index c94379e..bf2eb0d 100644
--- a/drivers/usb/core/usb.h
+++ b/drivers/usb/core/usb.h
@@ -78,15 +78,13 @@
extern struct workqueue_struct *ksuspend_usb_wq;
extern struct bus_type usb_bus_type;
+extern struct device_type usb_device_type;
+extern struct device_type usb_if_device_type;
extern struct usb_device_driver usb_generic_driver;
-/* Here's how we tell apart devices and interfaces. Luckily there's
- * no such thing as a platform USB device, so we can steal the use
- * of the platform_data field. */
-
static inline int is_usb_device(const struct device *dev)
{
- return dev->platform_data == &usb_generic_driver;
+ return dev->type == &usb_device_type;
}
/* Do the same for device drivers and interface drivers. */
@@ -122,11 +120,11 @@
extern struct mutex usbfs_mutex;
extern struct usb_driver usbfs_driver;
extern const struct file_operations usbfs_devices_fops;
-extern const struct file_operations usbfs_device_file_operations;
+extern const struct file_operations usbdev_file_operations;
extern void usbfs_conn_disc_event(void);
-extern int usbdev_init(void);
-extern void usbdev_cleanup(void);
+extern int usb_devio_init(void);
+extern void usb_devio_cleanup(void);
struct dev_state {
struct list_head list; /* state list */
