diff options
Diffstat (limited to 'drivers/base/driver.c')
| -rw-r--r-- | drivers/base/driver.c | 139 |
1 files changed, 46 insertions, 93 deletions
diff --git a/drivers/base/driver.c b/drivers/base/driver.c index 9a6537f1440..9e29943e56c 100644 --- a/drivers/base/driver.c +++ b/drivers/base/driver.c @@ -13,16 +13,22 @@ #include <linux/device.h> #include <linux/module.h> #include <linux/errno.h> +#include <linux/slab.h> #include <linux/string.h> +#include <linux/sysfs.h> #include "base.h" -#define to_dev(node) container_of(node, struct device, driver_list) - - static struct device *next_device(struct klist_iter *i) { struct klist_node *n = klist_next(i); - return n ? container_of(n, struct device, knode_driver) : NULL; + struct device *dev = NULL; + struct device_private *dev_prv; + + if (n) { + dev_prv = to_device_private_driver(n); + dev = dev_prv->device; + } + return dev; } /** @@ -45,7 +51,7 @@ int driver_for_each_device(struct device_driver *drv, struct device *start, return -EINVAL; klist_iter_init_node(&drv->p->klist_devices, &i, - start ? &start->knode_driver : NULL); + start ? &start->p->knode_driver : NULL); while ((dev = next_device(&i)) && !error) error = fn(dev, data); klist_iter_exit(&i); @@ -75,11 +81,11 @@ struct device *driver_find_device(struct device_driver *drv, struct klist_iter i; struct device *dev; - if (!drv) + if (!drv || !drv->p) return NULL; klist_iter_init_node(&drv->p->klist_devices, &i, - (start ? &start->knode_driver : NULL)); + (start ? &start->p->knode_driver : NULL)); while ((dev = next_device(&i))) if (match(dev, data) && get_device(dev)) break; @@ -94,7 +100,7 @@ EXPORT_SYMBOL_GPL(driver_find_device); * @attr: driver attribute descriptor. */ int driver_create_file(struct device_driver *drv, - struct driver_attribute *attr) + const struct driver_attribute *attr) { int error; if (drv) @@ -111,99 +117,23 @@ EXPORT_SYMBOL_GPL(driver_create_file); * @attr: driver attribute descriptor. */ void driver_remove_file(struct device_driver *drv, - struct driver_attribute *attr) + const struct driver_attribute *attr) { if (drv) sysfs_remove_file(&drv->p->kobj, &attr->attr); } EXPORT_SYMBOL_GPL(driver_remove_file); -/** - * driver_add_kobj - add a kobject below the specified driver - * @drv: requesting device driver - * @kobj: kobject to add below this driver - * @fmt: format string that names the kobject - * - * You really don't want to do this, this is only here due to one looney - * iseries driver, go poke those developers if you are annoyed about - * this... - */ -int driver_add_kobj(struct device_driver *drv, struct kobject *kobj, - const char *fmt, ...) +int driver_add_groups(struct device_driver *drv, + const struct attribute_group **groups) { - va_list args; - char *name; - int ret; - - va_start(args, fmt); - name = kvasprintf(GFP_KERNEL, fmt, args); - va_end(args); - - if (!name) - return -ENOMEM; - - ret = kobject_add(kobj, &drv->p->kobj, "%s", name); - kfree(name); - return ret; + return sysfs_create_groups(&drv->p->kobj, groups); } -EXPORT_SYMBOL_GPL(driver_add_kobj); -/** - * get_driver - increment driver reference count. - * @drv: driver. - */ -struct device_driver *get_driver(struct device_driver *drv) +void driver_remove_groups(struct device_driver *drv, + const struct attribute_group **groups) { - if (drv) { - struct driver_private *priv; - struct kobject *kobj; - - kobj = kobject_get(&drv->p->kobj); - priv = to_driver(kobj); - return priv->driver; - } - return NULL; -} -EXPORT_SYMBOL_GPL(get_driver); - -/** - * put_driver - decrement driver's refcount. - * @drv: driver. - */ -void put_driver(struct device_driver *drv) -{ - kobject_put(&drv->p->kobj); -} -EXPORT_SYMBOL_GPL(put_driver); - -static int driver_add_groups(struct device_driver *drv, - struct attribute_group **groups) -{ - int error = 0; - int i; - - if (groups) { - for (i = 0; groups[i]; i++) { - error = sysfs_create_group(&drv->p->kobj, groups[i]); - if (error) { - while (--i >= 0) - sysfs_remove_group(&drv->p->kobj, - groups[i]); - break; - } - } - } - return error; -} - -static void driver_remove_groups(struct device_driver *drv, - struct attribute_group **groups) -{ - int i; - - if (groups) - for (i = 0; groups[i]; i++) - sysfs_remove_group(&drv->p->kobj, groups[i]); + sysfs_remove_groups(&drv->p->kobj, groups); } /** @@ -217,18 +147,33 @@ static void driver_remove_groups(struct device_driver *drv, int driver_register(struct device_driver *drv) { int ret; + struct device_driver *other; + + BUG_ON(!drv->bus->p); if ((drv->bus->probe && drv->probe) || (drv->bus->remove && drv->remove) || (drv->bus->shutdown && drv->shutdown)) printk(KERN_WARNING "Driver '%s' needs updating - please use " "bus_type methods\n", drv->name); + + other = driver_find(drv->name, drv->bus); + if (other) { + printk(KERN_ERR "Error: Driver '%s' is already registered, " + "aborting...\n", drv->name); + return -EBUSY; + } + ret = bus_add_driver(drv); if (ret) return ret; ret = driver_add_groups(drv, drv->groups); - if (ret) + if (ret) { bus_remove_driver(drv); + return ret; + } + kobject_uevent(&drv->p->kobj, KOBJ_ADD); + return ret; } EXPORT_SYMBOL_GPL(driver_register); @@ -241,6 +186,10 @@ EXPORT_SYMBOL_GPL(driver_register); */ void driver_unregister(struct device_driver *drv) { + if (!drv || !drv->p) { + WARN(1, "Unexpected driver unregister!\n"); + return; + } driver_remove_groups(drv, drv->groups); bus_remove_driver(drv); } @@ -254,7 +203,9 @@ EXPORT_SYMBOL_GPL(driver_unregister); * Call kset_find_obj() to iterate over list of drivers on * a bus to find driver by name. Return driver if found. * - * Note that kset_find_obj increments driver's reference count. + * This routine provides no locking to prevent the driver it returns + * from being unregistered or unloaded while the caller is using it. + * The caller is responsible for preventing this. */ struct device_driver *driver_find(const char *name, struct bus_type *bus) { @@ -262,6 +213,8 @@ struct device_driver *driver_find(const char *name, struct bus_type *bus) struct driver_private *priv; if (k) { + /* Drop reference added by kset_find_obj() */ + kobject_put(k); priv = to_driver(k); return priv->driver; } |