From 2ee97caf0a6602f749ddbfdb1449e383e1212707 Mon Sep 17 00:00:00 2001 From: Cornelia Huck Date: Wed, 18 Jul 2007 01:43:47 -0700 Subject: [PATCH] Driver core: check return code of sysfs_create_link() Check for return value of sysfs_create_link() in device_add() and device_rename(). Add helper functions device_add_class_symlinks() and device_remove_class_symlinks() to make the code easier to read. [akpm@linux-foundation.org: fix unused var warnings] Signed-off-by: Cornelia Huck Acked-by: Jeff Garzik Signed-off-by: Andrew Morton Signed-off-by: Greg Kroah-Hartman --- drivers/base/core.c | 145 ++++++++++++++++++++++++++++++++------------ 1 file changed, 105 insertions(+), 40 deletions(-) diff --git a/drivers/base/core.c b/drivers/base/core.c index 91a0367d583e..3599ab2506d2 100644 --- a/drivers/base/core.c +++ b/drivers/base/core.c @@ -660,6 +660,82 @@ static int setup_parent(struct device *dev, struct device *parent) return 0; } +static int device_add_class_symlinks(struct device *dev) +{ + int error; + + if (!dev->class) + return 0; + error = sysfs_create_link(&dev->kobj, &dev->class->subsys.kobj, + "subsystem"); + if (error) + goto out; + /* + * If this is not a "fake" compatible device, then create the + * symlink from the class to the device. + */ + if (dev->kobj.parent != &dev->class->subsys.kobj) { + error = sysfs_create_link(&dev->class->subsys.kobj, &dev->kobj, + dev->bus_id); + if (error) + goto out_subsys; + } + /* only bus-device parents get a "device"-link */ + if (dev->parent && dev->parent->bus) { + error = sysfs_create_link(&dev->kobj, &dev->parent->kobj, + "device"); + if (error) + goto out_busid; +#ifdef CONFIG_SYSFS_DEPRECATED + { + char * class_name = make_class_name(dev->class->name, + &dev->kobj); + if (class_name) + error = sysfs_create_link(&dev->parent->kobj, + &dev->kobj, class_name); + kfree(class_name); + if (error) + goto out_device; + } +#endif + } + return 0; + +#ifdef CONFIG_SYSFS_DEPRECATED +out_device: + if (dev->parent) + sysfs_remove_link(&dev->kobj, "device"); +#endif +out_busid: + if (dev->kobj.parent != &dev->class->subsys.kobj) + sysfs_remove_link(&dev->class->subsys.kobj, dev->bus_id); +out_subsys: + sysfs_remove_link(&dev->kobj, "subsystem"); +out: + return error; +} + +static void device_remove_class_symlinks(struct device *dev) +{ + if (!dev->class) + return; + if (dev->parent) { +#ifdef CONFIG_SYSFS_DEPRECATED + char *class_name; + + class_name = make_class_name(dev->class->name, &dev->kobj); + if (class_name) { + sysfs_remove_link(&dev->parent->kobj, class_name); + kfree(class_name); + } +#endif + sysfs_remove_link(&dev->kobj, "device"); + } + if (dev->kobj.parent != &dev->class->subsys.kobj) + sysfs_remove_link(&dev->class->subsys.kobj, dev->bus_id); + sysfs_remove_link(&dev->kobj, "subsystem"); +} + /** * device_add - add device to device hierarchy. * @dev: device. @@ -674,7 +750,6 @@ static int setup_parent(struct device *dev, struct device *parent) int device_add(struct device *dev) { struct device *parent = NULL; - char *class_name = NULL; struct class_interface *class_intf; int error = -EINVAL; @@ -714,27 +789,9 @@ int device_add(struct device *dev) goto ueventattrError; } - if (dev->class) { - sysfs_create_link(&dev->kobj, &dev->class->subsys.kobj, - "subsystem"); - /* If this is not a "fake" compatible device, then create the - * symlink from the class to the device. */ - if (dev->kobj.parent != &dev->class->subsys.kobj) - sysfs_create_link(&dev->class->subsys.kobj, - &dev->kobj, dev->bus_id); - if (parent) { - sysfs_create_link(&dev->kobj, &dev->parent->kobj, - "device"); -#ifdef CONFIG_SYSFS_DEPRECATED - class_name = make_class_name(dev->class->name, - &dev->kobj); - if (class_name) - sysfs_create_link(&dev->parent->kobj, - &dev->kobj, class_name); -#endif - } - } - + error = device_add_class_symlinks(dev); + if (error) + goto SymlinkError; error = device_add_attrs(dev); if (error) goto AttrsError; @@ -761,7 +818,6 @@ int device_add(struct device *dev) up(&dev->class->sem); } Done: - kfree(class_name); put_device(dev); return error; BusError: @@ -772,6 +828,8 @@ int device_add(struct device *dev) BUS_NOTIFY_DEL_DEVICE, dev); device_remove_attrs(dev); AttrsError: + device_remove_class_symlinks(dev); + SymlinkError: if (MAJOR(dev->devt)) device_remove_file(dev, &devt_attr); @@ -1156,7 +1214,7 @@ int device_rename(struct device *dev, char *new_name) { char *old_class_name = NULL; char *new_class_name = NULL; - char *old_symlink_name = NULL; + char *old_device_name = NULL; int error; dev = get_device(dev); @@ -1170,42 +1228,49 @@ int device_rename(struct device *dev, char *new_name) old_class_name = make_class_name(dev->class->name, &dev->kobj); #endif - if (dev->class) { - old_symlink_name = kmalloc(BUS_ID_SIZE, GFP_KERNEL); - if (!old_symlink_name) { - error = -ENOMEM; - goto out_free_old_class; - } - strlcpy(old_symlink_name, dev->bus_id, BUS_ID_SIZE); + old_device_name = kmalloc(BUS_ID_SIZE, GFP_KERNEL); + if (!old_device_name) { + error = -ENOMEM; + goto out; } - + strlcpy(old_device_name, dev->bus_id, BUS_ID_SIZE); strlcpy(dev->bus_id, new_name, BUS_ID_SIZE); error = kobject_rename(&dev->kobj, new_name); + if (error) { + strlcpy(dev->bus_id, old_device_name, BUS_ID_SIZE); + goto out; + } #ifdef CONFIG_SYSFS_DEPRECATED if (old_class_name) { new_class_name = make_class_name(dev->class->name, &dev->kobj); if (new_class_name) { - sysfs_create_link(&dev->parent->kobj, &dev->kobj, - new_class_name); + error = sysfs_create_link(&dev->parent->kobj, + &dev->kobj, new_class_name); + if (error) + goto out; sysfs_remove_link(&dev->parent->kobj, old_class_name); } } #endif if (dev->class) { - sysfs_remove_link(&dev->class->subsys.kobj, - old_symlink_name); - sysfs_create_link(&dev->class->subsys.kobj, &dev->kobj, - dev->bus_id); + sysfs_remove_link(&dev->class->subsys.kobj, old_device_name); + error = sysfs_create_link(&dev->class->subsys.kobj, &dev->kobj, + dev->bus_id); + if (error) { + /* Uh... how to unravel this if restoring can fail? */ + dev_err(dev, "%s: sysfs_create_symlink failed (%d)\n", + __FUNCTION__, error); + } } +out: put_device(dev); kfree(new_class_name); - kfree(old_symlink_name); - out_free_old_class: kfree(old_class_name); + kfree(old_device_name); return error; } -- 2.20.1