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 <cornelia.huck@de.ibm.com>
Acked-by: Jeff Garzik <jeff@garzik.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
diff --git a/drivers/base/core.c b/drivers/base/core.c
index 91a0367..3599ab2 100644
--- a/drivers/base/core.c
+++ b/drivers/base/core.c
@@ -660,6 +660,82 @@
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 @@
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 @@
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 @@
up(&dev->class->sem);
}
Done:
- kfree(class_name);
put_device(dev);
return error;
BusError:
@@ -772,6 +828,8 @@
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 @@
{
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 @@
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;
}