]> err.no Git - linux-2.6/commitdiff
USB: make usbdevices export their device nodes instead of using a separate class
authorKay Sievers <kay.sievers@vrfy.org>
Tue, 13 Mar 2007 14:59:31 +0000 (15:59 +0100)
committerGreg Kroah-Hartman <gregkh@suse.de>
Fri, 27 Apr 2007 20:28:37 +0000 (13:28 -0700)
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>
drivers/usb/core/Kconfig
drivers/usb/core/devio.c
drivers/usb/core/driver.c
drivers/usb/core/hub.c
drivers/usb/core/inode.c
drivers/usb/core/message.c
drivers/usb/core/usb.c
drivers/usb/core/usb.h
include/linux/usb.h

index 2fc0f88a3d860818947002ed91d8213a51d22f8f..f493fb1eaa274fccef4266ae6784e91c165c3935 100644 (file)
@@ -31,7 +31,30 @@ config USB_DEVICEFS
          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)"
index fc3545ddb06e14d7b8b25fc61768f9b82ec489a9..e023f3d562483cc2c7dfd1052d83b2eb7ca30b39 100644 (file)
@@ -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 @@ static int check_ctrlrecip(struct dev_state *ps, unsigned int requesttype, unsig
        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 @@ static int usbdev_open(struct inode *inode, struct file *file)
                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 @@ static unsigned int usbdev_poll(struct file *file, struct poll_table_struct *wai
        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 @@ const struct file_operations usbfs_device_file_operations = {
        .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 @@ int __init usbdev_init(void)
                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);
 }
-
index 9b6a60fafddb8a457540330d4dea85efe68e460f..593386eb974dc6f34b12d2419ae0357b03a69f4b 100644 (file)
@@ -574,23 +574,10 @@ static int usb_device_match(struct device *dev, struct device_driver *drv)
 }
 
 #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 @@ static int usb_uevent(struct device *dev, char **envp, int num_envp,
        /* 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 @@ static int usb_uevent(struct device *dev, char **envp, int num_envp,
 #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 @@ static int usb_uevent(struct device *dev, char **envp, int num_envp,
                           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 */
 
 /**
index 19abe81babd57fbbd724812f787925f825e82925..2a0b15e42bc75762054e09565ec928acb8f9f155 100644 (file)
@@ -1367,11 +1367,15 @@ int usb_new_device(struct usb_device *udev)
        }
 #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;
index 11dad22da41cc373d28957d47372e342c19fad9d..cddfc62c46114bb375094007a62f521d66f123bc 100644 (file)
@@ -662,7 +662,7 @@ static void usbfs_add_device(struct usb_device *dev)
        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");
index c359ccb32998c8ec64ec6d9d28b77c8c9b708ad8..da4ee07e0094c59d17e96166abe1ff346f23ea6b 100644 (file)
@@ -1305,7 +1305,7 @@ int usb_reset_configuration(struct usb_device *dev)
        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 @@ static void release_interface(struct device *dev)
        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 @@ free_interfaces:
                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",
index 6f35dce8a95db6f1c7988b3dcd7c903128eb2499..dfd1b5c87ca3ff69a0404920f1adcbc731d42729 100644 (file)
@@ -197,6 +197,11 @@ static void usb_release_dev(struct device *dev)
        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 @@ usb_alloc_dev(struct usb_device *parent, struct usb_bus *bus, unsigned port1)
 
        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 @@ static int __init usb_init(void)
        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 @@ static int __init usb_init(void)
 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 @@ static void __exit usb_exit(void)
        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);
index c94379e55f2dcd9a385b7159e5a4d01304c04d6b..bf2eb0dae2ecc3aeee8e08f2c941d59513c733fe 100644 (file)
@@ -78,15 +78,13 @@ static inline int usb_autoresume_device(struct usb_device *udev)
 
 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 const char *usbcore_name;
 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 */
index 5e8e144afbaefa549b62c972ee3e4b407f2a92cd..f9e4445d5b53fe00c06d9fa154059a2499d31402 100644 (file)
@@ -299,8 +299,9 @@ struct usb_bus {
        int bandwidth_int_reqs;         /* number of Interrupt requests */
        int bandwidth_isoc_reqs;        /* number of Isoc. requests */
 
+#ifdef CONFIG_USB_DEVICEFS
        struct dentry *usbfs_dentry;    /* usbfs dentry entry for the bus */
-
+#endif
        struct class_device *class_dev; /* class device for this bus */
 
 #if defined(CONFIG_USB_MON)
@@ -373,9 +374,12 @@ struct usb_device {
        char *serial;                   /* iSerialNumber string, if present */
 
        struct list_head filelist;
-       struct device *usbfs_dev;
+#ifdef CONFIG_USB_DEVICE_CLASS
+       struct device *usb_classdev;
+#endif
+#ifdef CONFIG_USB_DEVICEFS
        struct dentry *usbfs_dentry;    /* usbfs dentry entry for the device */
-
+#endif
        /*
         * Child devices - these can be either new devices
         * (if this is a hub device), or different instances