diff options
Diffstat (limited to 'drivers/misc/enclosure.c')
| -rw-r--r-- | drivers/misc/enclosure.c | 114 |
1 files changed, 74 insertions, 40 deletions
diff --git a/drivers/misc/enclosure.c b/drivers/misc/enclosure.c index 348443bdb23..2cf2bbc0b92 100644 --- a/drivers/misc/enclosure.c +++ b/drivers/misc/enclosure.c @@ -27,30 +27,51 @@ #include <linux/kernel.h> #include <linux/module.h> #include <linux/mutex.h> +#include <linux/slab.h> static LIST_HEAD(container_list); static DEFINE_MUTEX(container_list_lock); static struct class enclosure_class; /** - * enclosure_find - find an enclosure given a device - * @dev: the device to find for + * enclosure_find - find an enclosure given a parent device + * @dev: the parent to match against + * @start: Optional enclosure device to start from (NULL if none) * - * Looks through the list of registered enclosures to see - * if it can find a match for a device. Returns NULL if no - * enclosure is found. Obtains a reference to the enclosure class - * device which must be released with device_put(). + * Looks through the list of registered enclosures to find all those + * with @dev as a parent. Returns NULL if no enclosure is + * found. @start can be used as a starting point to obtain multiple + * enclosures per parent (should begin with NULL and then be set to + * each returned enclosure device). Obtains a reference to the + * enclosure class device which must be released with device_put(). + * If @start is not NULL, a reference must be taken on it which is + * released before returning (this allows a loop through all + * enclosures to exit with only the reference on the enclosure of + * interest held). Note that the @dev may correspond to the actual + * device housing the enclosure, in which case no iteration via @start + * is required. */ -struct enclosure_device *enclosure_find(struct device *dev) +struct enclosure_device *enclosure_find(struct device *dev, + struct enclosure_device *start) { struct enclosure_device *edev; mutex_lock(&container_list_lock); - list_for_each_entry(edev, &container_list, node) { - if (edev->edev.parent == dev) { - get_device(&edev->edev); - mutex_unlock(&container_list_lock); - return edev; + edev = list_prepare_entry(start, &container_list, node); + if (start) + put_device(&start->edev); + + list_for_each_entry_continue(edev, &container_list, node) { + struct device *parent = edev->edev.parent; + /* parent might not be immediate, so iterate up to + * the root of the tree if necessary */ + while (parent) { + if (parent == dev) { + get_device(&edev->edev); + mutex_unlock(&container_list_lock); + return edev; + } + parent = parent->parent; } } mutex_unlock(&container_list_lock); @@ -177,6 +198,13 @@ static void enclosure_remove_links(struct enclosure_component *cdev) { char name[ENCLOSURE_NAME_SIZE]; + /* + * In odd circumstances, like multipath devices, something else may + * already have removed the links, so check for this condition first. + */ + if (!cdev->dev->kobj.sd) + return; + enclosure_link_name(cdev, name); sysfs_remove_link(&cdev->dev->kobj, name); sysfs_remove_link(&cdev->cdev.kobj, "device"); @@ -218,7 +246,7 @@ static void enclosure_component_release(struct device *dev) put_device(dev->parent); } -static struct attribute_group *enclosure_groups[]; +static const struct attribute_group *enclosure_component_groups[]; /** * enclosure_component_register - add a particular component to an enclosure @@ -261,11 +289,14 @@ enclosure_component_register(struct enclosure_device *edev, dev_set_name(cdev, "%u", number); cdev->release = enclosure_component_release; - cdev->groups = enclosure_groups; + cdev->groups = enclosure_component_groups; err = device_register(cdev); - if (err) - ERR_PTR(err); + if (err) { + ecomp->number = -1; + put_device(cdev); + return ERR_PTR(err); + } return ecomp; } @@ -295,6 +326,9 @@ int enclosure_add_device(struct enclosure_device *edev, int component, cdev = &edev->component[component]; + if (cdev->dev == dev) + return -EEXIST; + if (cdev->dev) enclosure_remove_links(cdev); @@ -312,19 +346,25 @@ EXPORT_SYMBOL_GPL(enclosure_add_device); * Returns zero on success or an error. * */ -int enclosure_remove_device(struct enclosure_device *edev, int component) +int enclosure_remove_device(struct enclosure_device *edev, struct device *dev) { struct enclosure_component *cdev; + int i; - if (!edev || component >= edev->components) + if (!edev || !dev) return -EINVAL; - cdev = &edev->component[component]; - - device_del(&cdev->cdev); - put_device(cdev->dev); - cdev->dev = NULL; - return device_add(&cdev->cdev); + for (i = 0; i < edev->components; i++) { + cdev = &edev->component[i]; + if (cdev->dev == dev) { + enclosure_remove_links(cdev); + device_del(&cdev->cdev); + put_device(dev); + cdev->dev = NULL; + return device_add(&cdev->cdev); + } + } + return -ENODEV; } EXPORT_SYMBOL_GPL(enclosure_remove_device); @@ -332,25 +372,26 @@ EXPORT_SYMBOL_GPL(enclosure_remove_device); * sysfs pieces below */ -static ssize_t enclosure_show_components(struct device *cdev, - struct device_attribute *attr, - char *buf) +static ssize_t components_show(struct device *cdev, + struct device_attribute *attr, char *buf) { struct enclosure_device *edev = to_enclosure_device(cdev); return snprintf(buf, 40, "%d\n", edev->components); } +static DEVICE_ATTR_RO(components); -static struct device_attribute enclosure_attrs[] = { - __ATTR(components, S_IRUGO, enclosure_show_components, NULL), - __ATTR_NULL +static struct attribute *enclosure_class_attrs[] = { + &dev_attr_components.attr, + NULL, }; +ATTRIBUTE_GROUPS(enclosure_class); static struct class enclosure_class = { .name = "enclosure", .owner = THIS_MODULE, .dev_release = enclosure_release, - .dev_attrs = enclosure_attrs, + .dev_groups = enclosure_class_groups, }; static const char *const enclosure_status [] = { @@ -362,6 +403,7 @@ static const char *const enclosure_status [] = { [ENCLOSURE_STATUS_NOT_INSTALLED] = "not installed", [ENCLOSURE_STATUS_UNKNOWN] = "unknown", [ENCLOSURE_STATUS_UNAVAILABLE] = "unavailable", + [ENCLOSURE_STATUS_MAX] = NULL, }; static const char *const enclosure_type [] = { @@ -502,15 +544,7 @@ static struct attribute *enclosure_component_attrs[] = { &dev_attr_type.attr, NULL }; - -static struct attribute_group enclosure_group = { - .attrs = enclosure_component_attrs, -}; - -static struct attribute_group *enclosure_groups[] = { - &enclosure_group, - NULL -}; +ATTRIBUTE_GROUPS(enclosure_component); static int __init enclosure_init(void) { |