From akpm@osdl.org Mon Aug 14 22:43:38 2006 Message-Id: <200608150543.k7F5hKKf011753@shell0.pdx.osdl.net> Subject: [patch 5/9] drivers/base: check errors To: greg@kroah.com Cc: akpm@osdl.org, cornelia.huck@de.ibm.com, rdunlap@xenotime.net From: akpm@osdl.org Date: Mon, 14 Aug 2006 22:43:20 -0700 From: Andrew Morton Add lots of return-value checking. : fix bus_rescan_devices()] Cc: "Randy.Dunlap" Signed-off-by: Cornelia Huck Signed-off-by: Andrew Morton Signed-off-by: Greg Kroah-Hartman --- drivers/base/base.h | 2 drivers/base/bus.c | 107 ++++++++++++++++++++++++++++++++----------------- drivers/base/dd.c | 37 ++++++++++++---- include/linux/device.h | 8 +-- 4 files changed, 104 insertions(+), 50 deletions(-) --- gregkh-2.6.orig/drivers/base/base.h +++ gregkh-2.6/drivers/base/base.h @@ -16,7 +16,7 @@ extern int cpu_dev_init(void); extern int attribute_container_init(void); extern int bus_add_device(struct device * dev); -extern void bus_attach_device(struct device * dev); +extern int bus_attach_device(struct device * dev); extern void bus_remove_device(struct device * dev); extern struct bus_type *get_bus(struct bus_type * bus); extern void put_bus(struct bus_type * bus); --- gregkh-2.6.orig/drivers/base/bus.c +++ gregkh-2.6/drivers/base/bus.c @@ -371,12 +371,20 @@ int bus_add_device(struct device * dev) if (bus) { pr_debug("bus %s: add device %s\n", bus->name, dev->bus_id); error = device_add_attrs(bus, dev); - if (!error) { - sysfs_create_link(&bus->devices.kobj, &dev->kobj, dev->bus_id); - sysfs_create_link(&dev->kobj, &dev->bus->subsys.kset.kobj, "subsystem"); - sysfs_create_link(&dev->kobj, &dev->bus->subsys.kset.kobj, "bus"); - } + if (error) + goto out; + error = sysfs_create_link(&bus->devices.kobj, + &dev->kobj, dev->bus_id); + if (error) + goto out; + error = sysfs_create_link(&dev->kobj, + &dev->bus->subsys.kset.kobj, "subsystem"); + if (error) + goto out; + error = sysfs_create_link(&dev->kobj, + &dev->bus->subsys.kset.kobj, "bus"); } +out: return error; } @@ -386,14 +394,19 @@ int bus_add_device(struct device * dev) * * - Try to attach to driver. */ -void bus_attach_device(struct device * dev) +int bus_attach_device(struct device * dev) { - struct bus_type * bus = dev->bus; + struct bus_type *bus = dev->bus; + int ret = 0; if (bus) { - device_attach(dev); - klist_add_tail(&dev->knode_bus, &bus->klist_devices); + ret = device_attach(dev); + if (ret >= 0) { + klist_add_tail(&dev->knode_bus, &bus->klist_devices); + ret = 0; + } } + return ret; } /** @@ -455,10 +468,17 @@ static void driver_remove_attrs(struct b * Thanks to drivers making their tables __devinit, we can't allow manual * bind and unbind from userspace unless CONFIG_HOTPLUG is enabled. */ -static void add_bind_files(struct device_driver *drv) +static int __must_check add_bind_files(struct device_driver *drv) { - driver_create_file(drv, &driver_attr_unbind); - driver_create_file(drv, &driver_attr_bind); + int ret; + + ret = driver_create_file(drv, &driver_attr_unbind); + if (ret == 0) { + ret = driver_create_file(drv, &driver_attr_bind); + if (ret) + driver_remove_file(drv, &driver_attr_unbind); + } + return ret; } static void remove_bind_files(struct device_driver *drv) @@ -476,7 +496,7 @@ static inline void remove_bind_files(str * @drv: driver. * */ -int bus_add_driver(struct device_driver * drv) +int bus_add_driver(struct device_driver *drv) { struct bus_type * bus = get_bus(drv->bus); int error = 0; @@ -484,27 +504,39 @@ int bus_add_driver(struct device_driver if (bus) { pr_debug("bus %s: add driver %s\n", bus->name, drv->name); error = kobject_set_name(&drv->kobj, "%s", drv->name); - if (error) { - put_bus(bus); - return error; - } + if (error) + goto out_put_bus; drv->kobj.kset = &bus->drivers; - if ((error = kobject_register(&drv->kobj))) { - put_bus(bus); - return error; - } + if ((error = kobject_register(&drv->kobj))) + goto out_put_bus; - driver_attach(drv); + error = driver_attach(drv); + if (error) + goto out_unregister; klist_add_tail(&drv->knode_bus, &bus->klist_drivers); module_add_driver(drv->owner, drv); - driver_add_attrs(bus, drv); - add_bind_files(drv); + error = driver_add_attrs(bus, drv); + if (error) { + /* How the hell do we get out of this pickle? Give up */ + printk(KERN_ERR "%s: driver_add_attrs(%s) failed\n", + __FUNCTION__, drv->name); + } + error = add_bind_files(drv); + if (error) { + /* Ditto */ + printk(KERN_ERR "%s: add_bind_files(%s) failed\n", + __FUNCTION__, drv->name); + } } return error; +out_unregister: + kobject_unregister(&drv->kobj); +out_put_bus: + put_bus(bus); + return error; } - /** * bus_remove_driver - delete driver from bus's knowledge. * @drv: driver. @@ -530,16 +562,21 @@ void bus_remove_driver(struct device_dri /* Helper for bus_rescan_devices's iter */ -static int bus_rescan_devices_helper(struct device *dev, void *data) +static int __must_check bus_rescan_devices_helper(struct device *dev, + void *data) { + int ret = 0; + if (!dev->driver) { if (dev->parent) /* Needed for USB */ down(&dev->parent->sem); - device_attach(dev); + ret = device_attach(dev); if (dev->parent) up(&dev->parent->sem); + if (ret > 0) + ret = 0; } - return 0; + return ret < 0 ? ret : 0; } /** @@ -550,9 +587,9 @@ static int bus_rescan_devices_helper(str * attached and rescan it against existing drivers to see if it matches * any by calling device_attach() for the unbound devices. */ -void bus_rescan_devices(struct bus_type * bus) +int bus_rescan_devices(struct bus_type * bus) { - bus_for_each_dev(bus, NULL, NULL, bus_rescan_devices_helper); + return bus_for_each_dev(bus, NULL, NULL, bus_rescan_devices_helper); } /** @@ -564,7 +601,7 @@ void bus_rescan_devices(struct bus_type * to use if probing criteria changed during a devices lifetime and * driver attachment should change accordingly. */ -void device_reprobe(struct device *dev) +int device_reprobe(struct device *dev) { if (dev->driver) { if (dev->parent) /* Needed for USB */ @@ -573,14 +610,14 @@ void device_reprobe(struct device *dev) if (dev->parent) up(&dev->parent->sem); } - - bus_rescan_devices_helper(dev, NULL); + return bus_rescan_devices_helper(dev, NULL); } EXPORT_SYMBOL_GPL(device_reprobe); -struct bus_type * get_bus(struct bus_type * bus) +struct bus_type *get_bus(struct bus_type *bus) { - return bus ? container_of(subsys_get(&bus->subsys), struct bus_type, subsys) : NULL; + return bus ? container_of(subsys_get(&bus->subsys), + struct bus_type, subsys) : NULL; } void put_bus(struct bus_type * bus) --- gregkh-2.6.orig/drivers/base/dd.c +++ gregkh-2.6/drivers/base/dd.c @@ -38,17 +38,29 @@ * * This function must be called with @dev->sem held. */ -void device_bind_driver(struct device * dev) +int device_bind_driver(struct device *dev) { - if (klist_node_attached(&dev->knode_driver)) - return; + int ret; + + if (klist_node_attached(&dev->knode_driver)) { + printk(KERN_WARNING "%s: device %s already bound\n", + __FUNCTION__, kobject_name(&dev->kobj)); + return 0; + } pr_debug("bound device '%s' to driver '%s'\n", dev->bus_id, dev->driver->name); klist_add_tail(&dev->knode_driver, &dev->driver->klist_devices); - sysfs_create_link(&dev->driver->kobj, &dev->kobj, + ret = sysfs_create_link(&dev->driver->kobj, &dev->kobj, kobject_name(&dev->kobj)); - sysfs_create_link(&dev->kobj, &dev->driver->kobj, "driver"); + if (ret == 0) { + ret = sysfs_create_link(&dev->kobj, &dev->driver->kobj, + "driver"); + if (ret) + sysfs_remove_link(&dev->driver->kobj, + kobject_name(&dev->kobj)); + } + return ret; } /** @@ -91,7 +103,11 @@ int driver_probe_device(struct device_dr goto ProbeFailed; } } - device_bind_driver(dev); + if (device_bind_driver(dev)) { + printk(KERN_ERR "%s: device_bind_driver(%s) failed\n", + __FUNCTION__, dev->bus_id); + /* How does undo a ->probe? We're screwed. */ + } ret = 1; pr_debug("%s: Bound Device %s to Driver %s\n", drv->bus->name, dev->bus_id, drv->name); @@ -139,8 +155,9 @@ int device_attach(struct device * dev) down(&dev->sem); if (dev->driver) { - device_bind_driver(dev); - ret = 1; + ret = device_bind_driver(dev); + if (ret == 0) + ret = 1; } else ret = bus_for_each_drv(dev->bus, NULL, dev, __device_attach); up(&dev->sem); @@ -182,9 +199,9 @@ static int __driver_attach(struct device * returns 0 and the @dev->driver is set, we've found a * compatible pair. */ -void driver_attach(struct device_driver * drv) +int driver_attach(struct device_driver * drv) { - bus_for_each_dev(drv->bus, NULL, drv, __driver_attach); + return bus_for_each_dev(drv->bus, NULL, drv, __driver_attach); } /** --- gregkh-2.6.orig/include/linux/device.h +++ gregkh-2.6/include/linux/device.h @@ -62,7 +62,7 @@ struct bus_type { extern int __must_check bus_register(struct bus_type * bus); extern void bus_unregister(struct bus_type * bus); -extern void bus_rescan_devices(struct bus_type * bus); +extern int __must_check bus_rescan_devices(struct bus_type * bus); /* iterator helpers for buses */ @@ -397,11 +397,11 @@ extern int device_rename(struct device * * Manual binding of a device to driver. See drivers/base/bus.c * for information on use. */ -extern void device_bind_driver(struct device * dev); +extern int __must_check device_bind_driver(struct device *dev); extern void device_release_driver(struct device * dev); extern int __must_check device_attach(struct device * dev); -extern void driver_attach(struct device_driver * drv); -extern void device_reprobe(struct device *dev); +extern int __must_check driver_attach(struct device_driver *drv); +extern int __must_check device_reprobe(struct device *dev); /* * Easy functions for dynamically creating devices on the fly