From fbf82fd2e1f4e679c60516d772d1862c941ca845 Mon Sep 17 00:00:00 2001 From: Kay Sievers Date: Sun, 31 Jul 2005 01:05:53 +0200 Subject: [PATCH] USB: real nodes instead of usbfs This patch introduces a /sys/class/usb_device/ class where every connected usb-device will show up: tree /sys/class/usb_device/ /sys/class/usb_device/ |-- usb1.1 | |-- dev | `-- device -> ../../../devices/pci0000:00/0000:00:1d.0/usb1 |-- usb2.1 | |-- dev | `-- device -> ../../../devices/pci0000:00/0000:00:1d.1/usb2 ... The presence of the "dev" file lets udev create real device nodes. kay@pim:~/src/linux-2.6> tree /dev/bus/usb/ /dev/bus/usb/ |-- 1 | `-- 1 |-- 2 | `-- 1 ... udev rule: SUBSYSTEM="usb_device", PROGRAM="/sbin/usb_device %k", NAME="%c" (echo $1 | /bin/sed 's/usb\([0-9]*\)\.\([0-9]*\)/bus\/usb\/\1\/\2/') This makes libusb pick up the real nodes instead of the mounted usbfs: export USB_DEVFS_PATH=/dev/bus/usb Background: All this makes it possible to manage usb devices with udev instead of the devfs solution. We are currently working on a pam_console/resmgr replacement driven by udev and a pam-helper. It applies ACL's to device nodes, which is required for modern desktop functionalty like "Fast User Switching" or multiple local login support. New patch with its own major. I've succesfully disabled usbfs and use real nodes only on my box. With: "export USB_DEVFS_PATH=/dev/bus/usb" libusb picks up the udev managed nodes instead of reading usbfs files. This makes udev to provide symlinks for libusb to pick up: SUBSYSTEM="usb_device", PROGRAM="/sbin/usbdevice %k", SYMLINK="%c" /sbin/usbdevice: #!/bin/sh echo $1 | /bin/sed 's/usbdev\([0-9]*\)\.\([0-9]*\)/bus\/usb\/\1\/\2/' Signed-off-by: Kay Sievers Signed-off-by: Greg Kroah-Hartman --- drivers/usb/core/devio.c | 91 ++++++++++++++++++++++++++++++++++++++++++++++-- 1 file changed, 89 insertions(+), 2 deletions(-) (limited to 'drivers/usb/core/devio.c') diff --git a/drivers/usb/core/devio.c b/drivers/usb/core/devio.c index f86bf1454e2..d12bc5e84a1 100644 --- a/drivers/usb/core/devio.c +++ b/drivers/usb/core/devio.c @@ -43,6 +43,7 @@ #include #include #include +#include #include #include #include @@ -50,6 +51,10 @@ #include "hcd.h" /* for usbcore internals */ #include "usb.h" +#define USB_MAXBUS 64 +#define USB_DEVICE_MAX USB_MAXBUS * 128 +static struct class *usb_device_class; + struct async { struct list_head asynclist; struct dev_state *ps; @@ -487,7 +492,7 @@ static int check_ctrlrecip(struct dev_state *ps, unsigned int requesttype, unsig */ static int usbdev_open(struct inode *inode, struct file *file) { - struct usb_device *dev; + struct usb_device *dev = NULL; struct dev_state *ps; int ret; @@ -501,11 +506,16 @@ static int usbdev_open(struct inode *inode, struct file *file) lock_kernel(); ret = -ENOENT; - dev = usb_get_dev(inode->u.generic_ip); + /* check if we are called from a real node or usbfs */ + if (imajor(inode) == USB_DEVICE_MAJOR) + dev = usbdev_lookup_minor(iminor(inode)); + if (!dev) + dev = inode->u.generic_ip; if (!dev) { kfree(ps); goto out; } + usb_get_dev(dev); ret = 0; ps->dev = dev; ps->file = file; @@ -1477,3 +1487,80 @@ struct file_operations usbfs_device_file_operations = { .open = usbdev_open, .release = usbdev_release, }; + +struct usb_device *usbdev_lookup_minor(int minor) +{ + struct class_device *class_dev; + struct usb_device *dev = NULL; + + down(&usb_device_class->sem); + list_for_each_entry(class_dev, &usb_device_class->children, node) { + if (class_dev->devt == MKDEV(USB_DEVICE_MAJOR, minor)) { + dev = class_dev->class_data; + break; + } + } + up(&usb_device_class->sem); + + return dev; +}; + +void usbdev_add(struct usb_device *dev) +{ + int minor = ((dev->bus->busnum-1) * 128) + (dev->devnum-1); + + dev->class_dev = class_device_create(usb_device_class, + MKDEV(USB_DEVICE_MAJOR, minor), &dev->dev, + "usbdev%d.%d", dev->bus->busnum, dev->devnum); + + dev->class_dev->class_data = dev; +} + +void usbdev_remove(struct usb_device *dev) +{ + class_device_unregister(dev->class_dev); +} + +static struct cdev usb_device_cdev = { + .kobj = {.name = "usb_device", }, + .owner = THIS_MODULE, +}; + +int __init usbdev_init(void) +{ + int retval; + + retval = register_chrdev_region(MKDEV(USB_DEVICE_MAJOR, 0), + USB_DEVICE_MAX, "usb_device"); + if (retval) { + err("unable to register minors for usb_device"); + goto out; + } + cdev_init(&usb_device_cdev, &usbfs_device_file_operations); + retval = cdev_add(&usb_device_cdev, + MKDEV(USB_DEVICE_MAJOR, 0), USB_DEVICE_MAX); + if (retval) { + err("unable to get usb_device major %d", USB_DEVICE_MAJOR); + unregister_chrdev_region(USB_DEVICE_MAJOR, USB_DEVICE_MAX); + goto out; + } + usb_device_class = class_create(THIS_MODULE, "usb_device"); + if (IS_ERR(usb_device_class)) { + err("unable to register usb_device class"); + retval = PTR_ERR(usb_device_class); + usb_device_class = NULL; + cdev_del(&usb_device_cdev); + unregister_chrdev_region(USB_DEVICE_MAJOR, USB_DEVICE_MAX); + } + +out: + return retval; +} + +void usbdev_cleanup(void) +{ + class_destroy(usb_device_class); + cdev_del(&usb_device_cdev); + unregister_chrdev_region(USB_DEVICE_MAJOR, USB_DEVICE_MAX); +} + -- cgit v1.2.3 From fad21bdf56a25e1cb3e92bba33349de368e8f0b0 Mon Sep 17 00:00:00 2001 From: Alan Stern Date: Wed, 10 Aug 2005 15:15:57 -0400 Subject: [PATCH] USB: Fix regression in core/devio.c This patch (as551) fixes another little problem recently added to the USB core. Someone didn't fix the type of the first argument to unregister_chrdev_region. Signed-off-by: Alan Stern Signed-off-by: Greg Kroah-Hartman --- drivers/usb/core/devio.c | 15 ++++++++------- 1 file changed, 8 insertions(+), 7 deletions(-) (limited to 'drivers/usb/core/devio.c') diff --git a/drivers/usb/core/devio.c b/drivers/usb/core/devio.c index d12bc5e84a1..56c082f3492 100644 --- a/drivers/usb/core/devio.c +++ b/drivers/usb/core/devio.c @@ -76,6 +76,8 @@ MODULE_PARM_DESC (usbfs_snoop, "true to log all usbfs traffic"); dev_info( dev , format , ## arg); \ } while (0) +#define USB_DEVICE_DEV MKDEV(USB_DEVICE_MAJOR, 0) + #define MAX_USBFS_BUFFER_SIZE 16384 @@ -1530,18 +1532,17 @@ int __init usbdev_init(void) { int retval; - retval = register_chrdev_region(MKDEV(USB_DEVICE_MAJOR, 0), - USB_DEVICE_MAX, "usb_device"); + retval = register_chrdev_region(USB_DEVICE_DEV, USB_DEVICE_MAX, + "usb_device"); if (retval) { err("unable to register minors for usb_device"); goto out; } cdev_init(&usb_device_cdev, &usbfs_device_file_operations); - retval = cdev_add(&usb_device_cdev, - MKDEV(USB_DEVICE_MAJOR, 0), USB_DEVICE_MAX); + 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); - unregister_chrdev_region(USB_DEVICE_MAJOR, USB_DEVICE_MAX); + unregister_chrdev_region(USB_DEVICE_DEV, USB_DEVICE_MAX); goto out; } usb_device_class = class_create(THIS_MODULE, "usb_device"); @@ -1550,7 +1551,7 @@ int __init usbdev_init(void) retval = PTR_ERR(usb_device_class); usb_device_class = NULL; cdev_del(&usb_device_cdev); - unregister_chrdev_region(USB_DEVICE_MAJOR, USB_DEVICE_MAX); + unregister_chrdev_region(USB_DEVICE_DEV, USB_DEVICE_MAX); } out: @@ -1561,6 +1562,6 @@ void usbdev_cleanup(void) { class_destroy(usb_device_class); cdev_del(&usb_device_cdev); - unregister_chrdev_region(USB_DEVICE_MAJOR, USB_DEVICE_MAX); + unregister_chrdev_region(USB_DEVICE_DEV, USB_DEVICE_MAX); } -- cgit v1.2.3 From bf193d3cd2a3b73f2df74f57106114867946c09c Mon Sep 17 00:00:00 2001 From: Alan Stern Date: Wed, 10 Aug 2005 17:12:31 -0400 Subject: [PATCH] USB: Disconnect children when unbinding the hub driver This patch (as554) makes the hub driver disconnect any child USB devices when it is unbound from a hub. Normally this will never happen, but there are a few oddball ways to unbind the hub driver while leaving the children intact. For example, the new "unbind" sysfs attribute can be used for this purpose. Given that unbinding hubs with children is now safe, the patch also removes the code that prevented people from doing so using usbfs. Signed-off-by: Alan Stern Signed-off-by: Greg Kroah-Hartman --- drivers/usb/core/devio.c | 10 ---------- drivers/usb/core/hub.c | 42 ++++++++++++++++++++++++++++++++++++++++-- 2 files changed, 40 insertions(+), 12 deletions(-) (limited to 'drivers/usb/core/devio.c') diff --git a/drivers/usb/core/devio.c b/drivers/usb/core/devio.c index 56c082f3492..b4265aa7d45 100644 --- a/drivers/usb/core/devio.c +++ b/drivers/usb/core/devio.c @@ -1238,7 +1238,6 @@ static int proc_ioctl (struct dev_state *ps, void __user *arg) int retval = 0; struct usb_interface *intf = NULL; struct usb_driver *driver = NULL; - int i; /* get input parameters and alloc buffer */ if (copy_from_user(&ctrl, arg, sizeof (ctrl))) @@ -1270,15 +1269,6 @@ static int proc_ioctl (struct dev_state *ps, void __user *arg) /* disconnect kernel driver from interface */ case USBDEVFS_DISCONNECT: - /* don't allow the user to unbind the hub driver from - * a hub with children to manage */ - for (i = 0; i < ps->dev->maxchild; ++i) { - if (ps->dev->children[i]) - retval = -EBUSY; - } - if (retval) - break; - down_write(&usb_bus_type.subsys.rwsem); if (intf->dev.driver) { driver = to_usb_driver(intf->dev.driver); diff --git a/drivers/usb/core/hub.c b/drivers/usb/core/hub.c index 4a4b41f2665..9f54e8330f7 100644 --- a/drivers/usb/core/hub.c +++ b/drivers/usb/core/hub.c @@ -729,10 +729,29 @@ fail: static unsigned highspeed_hubs; +/* Called after the hub driver is unbound from a hub with children */ +static void hub_remove_children_work(void *__hub) +{ + struct usb_hub *hub = __hub; + struct usb_device *hdev = hub->hdev; + int i; + + kfree(hub); + + usb_lock_device(hdev); + for (i = 0; i < hdev->maxchild; ++i) { + if (hdev->children[i]) + usb_disconnect(&hdev->children[i]); + } + usb_unlock_device(hdev); + usb_put_dev(hdev); +} + static void hub_disconnect(struct usb_interface *intf) { struct usb_hub *hub = usb_get_intfdata (intf); struct usb_device *hdev; + int n, port1; usb_set_intfdata (intf, NULL); hdev = hub->hdev; @@ -760,8 +779,27 @@ static void hub_disconnect(struct usb_interface *intf) hub->buffer = NULL; } - /* Free the memory */ - kfree(hub); + /* If there are any children then this is an unbind only, not a + * physical disconnection. The active ports must be disabled + * and later on we must call usb_disconnect(). We can't call + * it now because we may not hold the hub's device lock. + */ + n = 0; + for (port1 = 1; port1 <= hdev->maxchild; ++port1) { + if (hdev->children[port1 - 1]) { + ++n; + hub_port_disable(hub, port1, 1); + } + } + + if (n == 0) + kfree(hub); + else { + /* Reuse the hub->leds work_struct for our own purposes */ + INIT_WORK(&hub->leds, hub_remove_children_work, hub); + schedule_work(&hub->leds); + usb_get_dev(hdev); + } } static int hub_probe(struct usb_interface *intf, const struct usb_device_id *id) -- cgit v1.2.3