sysfs: add sysfs_create/remove_groups()

These functions are being open-coded in 3 different places in the driver
core, and other driver subsystems will want to start doing this as well,
so move it to the sysfs core to keep it all in one place, where we know
it is written properly.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/base/bus.c b/drivers/base/bus.c
index 5ee5d3c1d74bb0e34e0341267b803dad94b0a6da..f099af0b41af951e76fc5bafb369910cb6fe75b6 100644 (file)
--- a/drivers/base/bus.c
+++ b/drivers/base/bus.c
@@ -884,32 +884,13 @@ static void bus_remove_attrs(struct bus_type *bus)
 static int bus_add_groups(struct bus_type *bus,
                          const struct attribute_group **groups)
 {
-       int error = 0;
-       int i;
-
-       if (groups) {
-               for (i = 0; groups[i]; i++) {
-                       error = sysfs_create_group(&bus->p->subsys.kobj,
-                                                  groups[i]);
-                       if (error) {
-                               while (--i >= 0)
-                                       sysfs_remove_group(&bus->p->subsys.kobj,
-                                                          groups[i]);
-                               break;
-                       }
-               }
-       }
-       return error;
+       return sysfs_create_groups(&bus->p->subsys.kobj, groups);
 }
 
 static void bus_remove_groups(struct bus_type *bus,
                              const struct attribute_group **groups)
 {
-       int i;
-
-       if (groups)
-               for (i = 0; groups[i]; i++)
-                       sysfs_remove_group(&bus->p->subsys.kobj, groups[i]);
+       sysfs_remove_groups(&bus->p->subsys.kobj, groups);
 }
 
 static void klist_devices_get(struct klist_node *n)

diff --git a/drivers/base/core.c b/drivers/base/core.c
index af646afa5b7ebc4c97d36e193f7981f5f533ed1a..d743dcee1e77ddcdc1cab0808f48ff262359e54c 100644 (file)
--- a/drivers/base/core.c
+++ b/drivers/base/core.c
@@ -493,31 +493,13 @@ static void device_remove_bin_attributes(struct device *dev,
 
 int device_add_groups(struct device *dev, const struct attribute_group **groups)
 {
-       int error = 0;
-       int i;
-
-       if (groups) {
-               for (i = 0; groups[i]; i++) {
-                       error = sysfs_create_group(&dev->kobj, groups[i]);
-                       if (error) {
-                               while (--i >= 0)
-                                       sysfs_remove_group(&dev->kobj,
-                                                          groups[i]);
-                               break;
-                       }
-               }
-       }
-       return error;
+       return sysfs_create_groups(&dev->kobj, groups);
 }
 
 void device_remove_groups(struct device *dev,
                          const struct attribute_group **groups)
 {
-       int i;
-
-       if (groups)
-               for (i = 0; groups[i]; i++)
-                       sysfs_remove_group(&dev->kobj, groups[i]);
+       sysfs_remove_groups(&dev->kobj, groups);
 }
 
 static int device_add_attrs(struct device *dev)

diff --git a/drivers/base/driver.c b/drivers/base/driver.c
index 89db726ebb98938e9ac898ecda229544a47e7957..c7efccb6f3bb3ffea19f0034f33143de3e7447c0 100644 (file)
--- a/drivers/base/driver.c
+++ b/drivers/base/driver.c
@@ -126,31 +126,13 @@ EXPORT_SYMBOL_GPL(driver_remove_file);
 int driver_add_groups(struct device_driver *drv,
                      const 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;
+       return sysfs_create_groups(&drv->p->kobj, groups);
 }
 
 void driver_remove_groups(struct device_driver *drv,
                          const 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);
 }
 
 /**

diff --git a/fs/sysfs/group.c b/fs/sysfs/group.c
index 09a1a25cd14540c77d0713b7d1ecd381f78c4886..68baf8501552842170870ef1ea0e0c8d97d36bcc 100644 (file)
--- a/fs/sysfs/group.c
+++ b/fs/sysfs/group.c
@@ -130,6 +130,40 @@ int sysfs_create_group(struct kobject *kobj,
        return internal_create_group(kobj, 0, grp);
 }
 
+/**
+ * sysfs_create_groups - given a directory kobject, create a bunch of attribute groups
+ * @kobj:      The kobject to create the group on
+ * @groups:    The attribute groups to create, NULL terminated
+ *
+ * This function creates a bunch of attribute groups.  If an error occurs when
+ * creating a group, all previously created groups will be removed, unwinding
+ * everything back to the original state when this function was called.
+ * It will explicitly warn and error if any of the attribute files being
+ * created already exist.
+ *
+ * Returns 0 on success or error code from sysfs_create_groups on error.
+ */
+int sysfs_create_groups(struct kobject *kobj,
+                       const struct attribute_group **groups)
+{
+       int error = 0;
+       int i;
+
+       if (!groups)
+               return 0;
+
+       for (i = 0; groups[i]; i++) {
+               error = sysfs_create_group(kobj, groups[i]);
+               if (error) {
+                       while (--i >= 0)
+                               sysfs_remove_group(kobj, groups[i]);
+                       break;
+               }
+       }
+       return error;
+}
+EXPORT_SYMBOL_GPL(sysfs_create_groups);
+
 /**
  * sysfs_update_group - given a directory kobject, update an attribute group
  * @kobj:      The kobject to update the group on
@@ -178,6 +212,26 @@ void sysfs_remove_group(struct kobject * kobj,
        sysfs_put(sd);
 }
 
+/**
+ * sysfs_remove_groups - remove a list of groups
+ *
+ * kobj:       The kobject for the groups to be removed from
+ * groups:     NULL terminated list of groups to be removed
+ *
+ * If groups is not NULL, the all groups will be removed from the kobject
+ */
+void sysfs_remove_groups(struct kobject *kobj,
+                        const struct attribute_group **groups)
+{
+       int i;
+
+       if (!groups)
+               return;
+       for (i = 0; groups[i]; i++)
+               sysfs_remove_group(kobj, groups[i]);
+}
+EXPORT_SYMBOL_GPL(sysfs_remove_groups);
+
 /**
  * sysfs_merge_group - merge files into a pre-existing attribute group.
  * @kobj:      The kobject containing the group.

diff --git a/include/linux/sysfs.h b/include/linux/sysfs.h
index 0f04958623d70bca687990e096916d97c5fce8ef..4dbb9d31daa825c4dd1b83452920ce0dd122a584 100644 (file)
--- a/include/linux/sysfs.h
+++ b/include/linux/sysfs.h
@@ -215,10 +215,14 @@ void sysfs_delete_link(struct kobject *dir, struct kobject *targ,
 
 int __must_check sysfs_create_group(struct kobject *kobj,
                                    const struct attribute_group *grp);
+int __must_check sysfs_create_groups(struct kobject *kobj,
+                                    const struct attribute_group **groups);
 int sysfs_update_group(struct kobject *kobj,
                       const struct attribute_group *grp);
 void sysfs_remove_group(struct kobject *kobj,
                        const struct attribute_group *grp);
+void sysfs_remove_groups(struct kobject *kobj,
+                        const struct attribute_group **groups);
 int sysfs_add_file_to_group(struct kobject *kobj,
                        const struct attribute *attr, const char *group);
 void sysfs_remove_file_from_group(struct kobject *kobj,