ANDROID: sdcardfs: Refactor configfs interface

This refactors the configfs code to be more easily extended.
It will allow additional files to be added easily.

Bug: 34542611
Bug: 34262585
Change-Id: I73c9b0ae5ca7eb27f4ebef3e6807f088b512d539
Signed-off-by: Daniel Rosenberg <drosen@google.com>

1 files changed, 76 insertions, 80 deletions

diff --git a/fs/sdcardfs/packagelist.c b/fs/sdcardfs/packagelist.c
index dac5d0f7d2d..7321aa609dc 100755
--- a/fs/sdcardfs/packagelist.c
+++ b/fs/sdcardfs/packagelist.c
@@ -220,39 +220,29 @@ static void packagelist_destroy(void)
 	printk(KERN_INFO "sdcardfs: destroyed packagelist pkgld\n");
 }
 
-struct package_appid {
+struct package_details {
 	struct config_item item;
-	int add_pid;
+	const char* name;
 };
 
-static inline struct package_appid *to_package_appid(struct config_item *item)
+static inline struct package_details *to_package_details(struct config_item *item)
 {
-	return item ? container_of(item, struct package_appid, item) : NULL;
+	return item ? container_of(item, struct package_details, item) : NULL;
 }
 
-static struct configfs_attribute package_appid_attr_add_pid = {
-	.ca_owner = THIS_MODULE,
-	.ca_name = "appid",
-	.ca_mode = S_IRUGO | S_IWUGO,
-};
-
-static struct configfs_attribute *package_appid_attrs[] = {
-	&package_appid_attr_add_pid,
-	NULL,
-};
+CONFIGFS_ATTR_STRUCT(package_details);
+#define PACKAGE_DETAILS_ATTR(_name, _mode, _show, _store)	\
+struct package_details_attribute package_details_attr_##_name = __CONFIGFS_ATTR(_name, _mode, _show, _store)
 
-static ssize_t package_appid_attr_show(struct config_item *item,
-				      struct configfs_attribute *attr,
+static ssize_t package_details_appid_show(struct package_details *package_details,
 				      char *page)
 {
-	return scnprintf(page, PAGE_SIZE, "%u\n", get_appid(item->ci_name));
+	return scnprintf(page, PAGE_SIZE, "%u\n", get_appid(package_details->name));
 }
 
-static ssize_t package_appid_attr_store(struct config_item *item,
-				       struct configfs_attribute *attr,
+static ssize_t package_details_appid_store(struct package_details *package_details,
 				       const char *page, size_t count)
 {
-	struct package_appid *package_appid = to_package_appid(item);
 	unsigned int tmp;
 	int ret;
 
@@ -260,73 +250,76 @@ static ssize_t package_appid_attr_store(struct config_item *item,
 	if (ret)
 		return ret;
 
-	ret = insert_packagelist_entry(item->ci_name, tmp);
-	package_appid->add_pid = tmp;
+	ret = insert_packagelist_entry(package_details->name, tmp);
+
 	if (ret)
 		return ret;
 
 	return count;
 }
 
-static void package_appid_release(struct config_item *item)
+static void package_details_release(struct config_item *item)
 {
-	printk(KERN_INFO "sdcardfs: removing %s\n", item->ci_dentry->d_name.name);
-	/* item->ci_name is freed already, so we rely on the dentry */
-	remove_packagelist_entry(item->ci_dentry->d_name.name);
-	kfree(to_package_appid(item));
+	struct package_details *package_details = to_package_details(item);
+	printk(KERN_INFO "sdcardfs: removing %s\n", package_details->name);
+	remove_packagelist_entry(package_details->name);
+	kfree(package_details->name);
+	kfree(package_details);
 }
 
-static struct configfs_item_operations package_appid_item_ops = {
-	.release		= package_appid_release,
-	.show_attribute		= package_appid_attr_show,
-	.store_attribute	= package_appid_attr_store,
+PACKAGE_DETAILS_ATTR(appid, S_IRUGO | S_IWUGO, package_details_appid_show, package_details_appid_store);
+
+static struct configfs_attribute *package_details_attrs[] = {
+	&package_details_attr_appid.attr,
+	NULL,
+};
+
+CONFIGFS_ATTR_OPS(package_details);
+static struct configfs_item_operations package_details_item_ops = {
+	.release = package_details_release,
+	.show_attribute = package_details_attr_show,
+	.store_attribute = package_details_attr_store,
 };
 
 static struct config_item_type package_appid_type = {
-	.ct_item_ops	= &package_appid_item_ops,
-	.ct_attrs	= package_appid_attrs,
+	.ct_item_ops	= &package_details_item_ops,
+	.ct_attrs	= package_details_attrs,
 	.ct_owner	= THIS_MODULE,
 };
 
-
-struct sdcardfs_packages {
-	struct config_group group;
+struct packages {
+	struct configfs_subsystem subsystem;
 };
 
-static inline struct sdcardfs_packages *to_sdcardfs_packages(struct config_item *item)
+static inline struct packages *to_packages(struct config_item *item)
 {
-	return item ? container_of(to_config_group(item), struct sdcardfs_packages, group) : NULL;
+	return item ? container_of(to_configfs_subsystem(to_config_group(item)), struct packages, subsystem) : NULL;
 }
 
-static struct config_item *sdcardfs_packages_make_item(struct config_group *group, const char *name)
+CONFIGFS_ATTR_STRUCT(packages);
+#define PACKAGES_ATTR(_name, _mode, _show, _store)	\
+struct packages_attribute packages_attr_##_name = __CONFIGFS_ATTR(_name, _mode, _show, _store)
+#define PACKAGES_ATTR_RO(_name, _show)	\
+struct packages_attribute packages_attr_##_name = __CONFIGFS_ATTR_RO(_name, _show);
+
+static struct config_item *packages_make_item(struct config_group *group, const char *name)
 {
-	struct package_appid *package_appid;
+	struct package_details *package_details;
 
-	package_appid = kzalloc(sizeof(struct package_appid), GFP_KERNEL);
-	if (!package_appid)
+	package_details = kzalloc(sizeof(struct package_details), GFP_KERNEL);
+	if (!package_details)
+		return ERR_PTR(-ENOMEM);
+	package_details->name = kstrdup(name, GFP_KERNEL);
+	if (!package_details->name)
 		return ERR_PTR(-ENOMEM);
 
-	config_item_init_type_name(&package_appid->item, name,
+	config_item_init_type_name(&package_details->item, name,
 				   &package_appid_type);
 
-	package_appid->add_pid = 0;
-
-	return &package_appid->item;
+	return &package_details->item;
 }
 
-static struct configfs_attribute sdcardfs_packages_attr_description = {
-	.ca_owner = THIS_MODULE,
-	.ca_name = "packages_gid.list",
-	.ca_mode = S_IRUGO,
-};
-
-static struct configfs_attribute *sdcardfs_packages_attrs[] = {
-	&sdcardfs_packages_attr_description,
-	NULL,
-};
-
-static ssize_t packages_attr_show(struct config_item *item,
-					 struct configfs_attribute *attr,
+static ssize_t packages_list_show(struct packages *packages,
 					 char *page)
 {
 	struct hashtable_entry *hash_cur;
@@ -349,38 +342,41 @@ static ssize_t packages_attr_show(struct config_item *item,
 	return count;
 }
 
-static void sdcardfs_packages_release(struct config_item *item)
-{
+struct packages_attribute packages_attr_packages_gid_list = __CONFIGFS_ATTR_RO(packages_gid.list, packages_list_show);
 
-	printk(KERN_INFO "sdcardfs: destroyed something?\n");
-	kfree(to_sdcardfs_packages(item));
-}
+static struct configfs_attribute *packages_attrs[] = {
+	&packages_attr_packages_gid_list.attr,
+	NULL,
+};
 
-static struct configfs_item_operations sdcardfs_packages_item_ops = {
-	.release	= sdcardfs_packages_release,
-	.show_attribute	= packages_attr_show,
+CONFIGFS_ATTR_OPS(packages)
+static struct configfs_item_operations packages_item_ops = {
+	.show_attribute = packages_attr_show,
+	.store_attribute = packages_attr_store,
 };
 
 /*
  * Note that, since no extra work is required on ->drop_item(),
  * no ->drop_item() is provided.
  */
-static struct configfs_group_operations sdcardfs_packages_group_ops = {
-	.make_item	= sdcardfs_packages_make_item,
+static struct configfs_group_operations packages_group_ops = {
+	.make_item	= packages_make_item,
 };
 
-static struct config_item_type sdcardfs_packages_type = {
-	.ct_item_ops	= &sdcardfs_packages_item_ops,
-	.ct_group_ops	= &sdcardfs_packages_group_ops,
-	.ct_attrs	= sdcardfs_packages_attrs,
+static struct config_item_type packages_type = {
+	.ct_item_ops	= &packages_item_ops,
+	.ct_group_ops	= &packages_group_ops,
+	.ct_attrs	= packages_attrs,
 	.ct_owner	= THIS_MODULE,
 };
 
-static struct configfs_subsystem sdcardfs_packages_subsys = {
-	.su_group = {
-		.cg_item = {
-			.ci_namebuf = "sdcardfs",
-			.ci_type = &sdcardfs_packages_type,
+static struct packages sdcardfs_packages = {
+	.subsystem = {
+		.su_group = {
+			.cg_item = {
+				.ci_namebuf = "sdcardfs",
+				.ci_type = &packages_type,
+			},
 		},
 	},
 };
@@ -388,7 +384,7 @@ static struct configfs_subsystem sdcardfs_packages_subsys = {
 static int configfs_sdcardfs_init(void)
 {
 	int ret;
-	struct configfs_subsystem *subsys = &sdcardfs_packages_subsys;
+	struct configfs_subsystem *subsys = &sdcardfs_packages.subsystem;
 
 	config_group_init(&subsys->su_group);
 	mutex_init(&subsys->su_mutex);
@@ -403,7 +399,7 @@ static int configfs_sdcardfs_init(void)
 
 static void configfs_sdcardfs_exit(void)
 {
-	configfs_unregister_subsystem(&sdcardfs_packages_subsys);
+	configfs_unregister_subsystem(&sdcardfs_packages.subsystem);
 }
 
 int packagelist_init(void)