configfs: remove old API
authorChristoph Hellwig <hch@lst.de>
Sat, 3 Oct 2015 13:32:59 +0000 (15:32 +0200)
committerNicholas Bellinger <nab@linux-iscsi.org>
Wed, 14 Oct 2015 05:17:57 +0000 (22:17 -0700)
Remove the old show_attribute and store_attribute methods and update
the documentation.  Also replace the two C samples with a single new
one in the proper samples directory where people expect to find it.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
Documentation/filesystems/Makefile
Documentation/filesystems/configfs/Makefile [deleted file]
Documentation/filesystems/configfs/configfs.txt
Documentation/filesystems/configfs/configfs_example_explicit.c [deleted file]
fs/configfs/file.c
include/linux/configfs.h
samples/Kconfig
samples/Makefile
samples/configfs/Makefile [new file with mode: 0644]
samples/configfs/configfs_sample.c [moved from Documentation/filesystems/configfs/configfs_example_macros.c with 74% similarity]

index 13483d1..883010c 100644 (file)
@@ -1,5 +1,3 @@
-subdir-y := configfs
-
 # List of programs to build
 hostprogs-y := dnotify_test
 
diff --git a/Documentation/filesystems/configfs/Makefile b/Documentation/filesystems/configfs/Makefile
deleted file mode 100644 (file)
index be7ec5e..0000000
+++ /dev/null
@@ -1,3 +0,0 @@
-ifneq ($(CONFIG_CONFIGFS_FS),)
-obj-m += configfs_example_explicit.o configfs_example_macros.o
-endif
index b40fec9..af68efd 100644 (file)
@@ -160,12 +160,6 @@ among other things.  For that, it needs a type.
 
        struct configfs_item_operations {
                void (*release)(struct config_item *);
-               ssize_t (*show_attribute)(struct config_item *,
-                                         struct configfs_attribute *,
-                                         char *);
-               ssize_t (*store_attribute)(struct config_item *,
-                                          struct configfs_attribute *,
-                                          const char *, size_t);
                int (*allow_link)(struct config_item *src,
                                  struct config_item *target);
                int (*drop_link)(struct config_item *src,
@@ -183,9 +177,7 @@ The most basic function of a config_item_type is to define what
 operations can be performed on a config_item.  All items that have been
 allocated dynamically will need to provide the ct_item_ops->release()
 method.  This method is called when the config_item's reference count
-reaches zero.  Items that wish to display an attribute need to provide
-the ct_item_ops->show_attribute() method.  Similarly, storing a new
-attribute value uses the store_attribute() method.
+reaches zero.
 
 [struct configfs_attribute]
 
@@ -193,6 +185,8 @@ attribute value uses the store_attribute() method.
                char                    *ca_name;
                struct module           *ca_owner;
                umode_t                  ca_mode;
+               ssize_t (*show)(struct config_item *, char *);
+               ssize_t (*store)(struct config_item *, const char *, size_t);
        };
 
 When a config_item wants an attribute to appear as a file in the item's
@@ -202,10 +196,10 @@ config_item_type->ct_attrs.  When the item appears in configfs, the
 attribute file will appear with the configfs_attribute->ca_name
 filename.  configfs_attribute->ca_mode specifies the file permissions.
 
-If an attribute is readable and the config_item provides a
-ct_item_ops->show_attribute() method, that method will be called
-whenever userspace asks for a read(2) on the attribute.  The converse
-will happen for write(2).
+If an attribute is readable and provides a ->show method, that method will
+be called whenever userspace asks for a read(2) on the attribute.  If an
+attribute is writable and provides a ->store  method, that method will be
+be called whenever userspace asks for a write(2) on the attribute.
 
 [struct config_group]
 
@@ -311,20 +305,10 @@ the subsystem must be ready for it.
 [An Example]
 
 The best example of these basic concepts is the simple_children
-subsystem/group and the simple_child item in configfs_example_explicit.c
-and configfs_example_macros.c.  It shows a trivial object displaying and
-storing an attribute, and a simple group creating and destroying these
-children.
-
-The only difference between configfs_example_explicit.c and
-configfs_example_macros.c is how the attributes of the childless item
-are defined.  The childless item has extended attributes, each with
-their own show()/store() operation.  This follows a convention commonly
-used in sysfs.  configfs_example_explicit.c creates these attributes
-by explicitly defining the structures involved.  Conversely
-configfs_example_macros.c uses some convenience macros from configfs.h
-to define the attributes.  These macros are similar to their sysfs
-counterparts.
+subsystem/group and the simple_child item in
+samples/configfs/configfs_sample.c. It shows a trivial object displaying
+and storing an attribute, and a simple group creating and destroying
+these children.
 
 [Hierarchy Navigation and the Subsystem Mutex]
 
diff --git a/Documentation/filesystems/configfs/configfs_example_explicit.c b/Documentation/filesystems/configfs/configfs_example_explicit.c
deleted file mode 100644 (file)
index 1420233..0000000
+++ /dev/null
@@ -1,483 +0,0 @@
-/*
- * vim: noexpandtab ts=8 sts=0 sw=8:
- *
- * configfs_example_explicit.c - This file is a demonstration module
- *      containing a number of configfs subsystems.  It explicitly defines
- *      each structure without using the helper macros defined in
- *      configfs.h.
- *
- * This program is free software; you can redistribute it and/or
- * modify it under the terms of the GNU General Public
- * License as published by the Free Software Foundation; either
- * version 2 of the License, or (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
- * General Public License for more details.
- *
- * You should have received a copy of the GNU General Public
- * License along with this program; if not, write to the
- * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
- * Boston, MA 021110-1307, USA.
- *
- * Based on sysfs:
- *     sysfs is Copyright (C) 2001, 2002, 2003 Patrick Mochel
- *
- * configfs Copyright (C) 2005 Oracle.  All rights reserved.
- */
-
-#include <linux/init.h>
-#include <linux/module.h>
-#include <linux/slab.h>
-
-#include <linux/configfs.h>
-
-
-
-/*
- * 01-childless
- *
- * This first example is a childless subsystem.  It cannot create
- * any config_items.  It just has attributes.
- *
- * Note that we are enclosing the configfs_subsystem inside a container.
- * This is not necessary if a subsystem has no attributes directly
- * on the subsystem.  See the next example, 02-simple-children, for
- * such a subsystem.
- */
-
-struct childless {
-       struct configfs_subsystem subsys;
-       int showme;
-       int storeme;
-};
-
-struct childless_attribute {
-       struct configfs_attribute attr;
-       ssize_t (*show)(struct childless *, char *);
-       ssize_t (*store)(struct childless *, const char *, size_t);
-};
-
-static inline struct childless *to_childless(struct config_item *item)
-{
-       return item ? container_of(to_configfs_subsystem(to_config_group(item)), struct childless, subsys) : NULL;
-}
-
-static ssize_t childless_showme_read(struct childless *childless,
-                                    char *page)
-{
-       ssize_t pos;
-
-       pos = sprintf(page, "%d\n", childless->showme);
-       childless->showme++;
-
-       return pos;
-}
-
-static ssize_t childless_storeme_read(struct childless *childless,
-                                     char *page)
-{
-       return sprintf(page, "%d\n", childless->storeme);
-}
-
-static ssize_t childless_storeme_write(struct childless *childless,
-                                      const char *page,
-                                      size_t count)
-{
-       unsigned long tmp;
-       char *p = (char *) page;
-
-       tmp = simple_strtoul(p, &p, 10);
-       if ((*p != '\0') && (*p != '\n'))
-               return -EINVAL;
-
-       if (tmp > INT_MAX)
-               return -ERANGE;
-
-       childless->storeme = tmp;
-
-       return count;
-}
-
-static ssize_t childless_description_read(struct childless *childless,
-                                         char *page)
-{
-       return sprintf(page,
-"[01-childless]\n"
-"\n"
-"The childless subsystem is the simplest possible subsystem in\n"
-"configfs.  It does not support the creation of child config_items.\n"
-"It only has a few attributes.  In fact, it isn't much different\n"
-"than a directory in /proc.\n");
-}
-
-static struct childless_attribute childless_attr_showme = {
-       .attr   = { .ca_owner = THIS_MODULE, .ca_name = "showme", .ca_mode = S_IRUGO },
-       .show   = childless_showme_read,
-};
-static struct childless_attribute childless_attr_storeme = {
-       .attr   = { .ca_owner = THIS_MODULE, .ca_name = "storeme", .ca_mode = S_IRUGO | S_IWUSR },
-       .show   = childless_storeme_read,
-       .store  = childless_storeme_write,
-};
-static struct childless_attribute childless_attr_description = {
-       .attr = { .ca_owner = THIS_MODULE, .ca_name = "description", .ca_mode = S_IRUGO },
-       .show = childless_description_read,
-};
-
-static struct configfs_attribute *childless_attrs[] = {
-       &childless_attr_showme.attr,
-       &childless_attr_storeme.attr,
-       &childless_attr_description.attr,
-       NULL,
-};
-
-static ssize_t childless_attr_show(struct config_item *item,
-                                  struct configfs_attribute *attr,
-                                  char *page)
-{
-       struct childless *childless = to_childless(item);
-       struct childless_attribute *childless_attr =
-               container_of(attr, struct childless_attribute, attr);
-       ssize_t ret = 0;
-
-       if (childless_attr->show)
-               ret = childless_attr->show(childless, page);
-       return ret;
-}
-
-static ssize_t childless_attr_store(struct config_item *item,
-                                   struct configfs_attribute *attr,
-                                   const char *page, size_t count)
-{
-       struct childless *childless = to_childless(item);
-       struct childless_attribute *childless_attr =
-               container_of(attr, struct childless_attribute, attr);
-       ssize_t ret = -EINVAL;
-
-       if (childless_attr->store)
-               ret = childless_attr->store(childless, page, count);
-       return ret;
-}
-
-static struct configfs_item_operations childless_item_ops = {
-       .show_attribute         = childless_attr_show,
-       .store_attribute        = childless_attr_store,
-};
-
-static struct config_item_type childless_type = {
-       .ct_item_ops    = &childless_item_ops,
-       .ct_attrs       = childless_attrs,
-       .ct_owner       = THIS_MODULE,
-};
-
-static struct childless childless_subsys = {
-       .subsys = {
-               .su_group = {
-                       .cg_item = {
-                               .ci_namebuf = "01-childless",
-                               .ci_type = &childless_type,
-                       },
-               },
-       },
-};
-
-
-/* ----------------------------------------------------------------- */
-
-/*
- * 02-simple-children
- *
- * This example merely has a simple one-attribute child.  Note that
- * there is no extra attribute structure, as the child's attribute is
- * known from the get-go.  Also, there is no container for the
- * subsystem, as it has no attributes of its own.
- */
-
-struct simple_child {
-       struct config_item item;
-       int storeme;
-};
-
-static inline struct simple_child *to_simple_child(struct config_item *item)
-{
-       return item ? container_of(item, struct simple_child, item) : NULL;
-}
-
-static struct configfs_attribute simple_child_attr_storeme = {
-       .ca_owner = THIS_MODULE,
-       .ca_name = "storeme",
-       .ca_mode = S_IRUGO | S_IWUSR,
-};
-
-static struct configfs_attribute *simple_child_attrs[] = {
-       &simple_child_attr_storeme,
-       NULL,
-};
-
-static ssize_t simple_child_attr_show(struct config_item *item,
-                                     struct configfs_attribute *attr,
-                                     char *page)
-{
-       ssize_t count;
-       struct simple_child *simple_child = to_simple_child(item);
-
-       count = sprintf(page, "%d\n", simple_child->storeme);
-
-       return count;
-}
-
-static ssize_t simple_child_attr_store(struct config_item *item,
-                                      struct configfs_attribute *attr,
-                                      const char *page, size_t count)
-{
-       struct simple_child *simple_child = to_simple_child(item);
-       unsigned long tmp;
-       char *p = (char *) page;
-
-       tmp = simple_strtoul(p, &p, 10);
-       if (!p || (*p && (*p != '\n')))
-               return -EINVAL;
-
-       if (tmp > INT_MAX)
-               return -ERANGE;
-
-       simple_child->storeme = tmp;
-
-       return count;
-}
-
-static void simple_child_release(struct config_item *item)
-{
-       kfree(to_simple_child(item));
-}
-
-static struct configfs_item_operations simple_child_item_ops = {
-       .release                = simple_child_release,
-       .show_attribute         = simple_child_attr_show,
-       .store_attribute        = simple_child_attr_store,
-};
-
-static struct config_item_type simple_child_type = {
-       .ct_item_ops    = &simple_child_item_ops,
-       .ct_attrs       = simple_child_attrs,
-       .ct_owner       = THIS_MODULE,
-};
-
-
-struct simple_children {
-       struct config_group group;
-};
-
-static inline struct simple_children *to_simple_children(struct config_item *item)
-{
-       return item ? container_of(to_config_group(item), struct simple_children, group) : NULL;
-}
-
-static struct config_item *simple_children_make_item(struct config_group *group, const char *name)
-{
-       struct simple_child *simple_child;
-
-       simple_child = kzalloc(sizeof(struct simple_child), GFP_KERNEL);
-       if (!simple_child)
-               return ERR_PTR(-ENOMEM);
-
-       config_item_init_type_name(&simple_child->item, name,
-                                  &simple_child_type);
-
-       simple_child->storeme = 0;
-
-       return &simple_child->item;
-}
-
-static struct configfs_attribute simple_children_attr_description = {
-       .ca_owner = THIS_MODULE,
-       .ca_name = "description",
-       .ca_mode = S_IRUGO,
-};
-
-static struct configfs_attribute *simple_children_attrs[] = {
-       &simple_children_attr_description,
-       NULL,
-};
-
-static ssize_t simple_children_attr_show(struct config_item *item,
-                                        struct configfs_attribute *attr,
-                                        char *page)
-{
-       return sprintf(page,
-"[02-simple-children]\n"
-"\n"
-"This subsystem allows the creation of child config_items.  These\n"
-"items have only one attribute that is readable and writeable.\n");
-}
-
-static void simple_children_release(struct config_item *item)
-{
-       kfree(to_simple_children(item));
-}
-
-static struct configfs_item_operations simple_children_item_ops = {
-       .release        = simple_children_release,
-       .show_attribute = simple_children_attr_show,
-};
-
-/*
- * Note that, since no extra work is required on ->drop_item(),
- * no ->drop_item() is provided.
- */
-static struct configfs_group_operations simple_children_group_ops = {
-       .make_item      = simple_children_make_item,
-};
-
-static struct config_item_type simple_children_type = {
-       .ct_item_ops    = &simple_children_item_ops,
-       .ct_group_ops   = &simple_children_group_ops,
-       .ct_attrs       = simple_children_attrs,
-       .ct_owner       = THIS_MODULE,
-};
-
-static struct configfs_subsystem simple_children_subsys = {
-       .su_group = {
-               .cg_item = {
-                       .ci_namebuf = "02-simple-children",
-                       .ci_type = &simple_children_type,
-               },
-       },
-};
-
-
-/* ----------------------------------------------------------------- */
-
-/*
- * 03-group-children
- *
- * This example reuses the simple_children group from above.  However,
- * the simple_children group is not the subsystem itself, it is a
- * child of the subsystem.  Creation of a group in the subsystem creates
- * a new simple_children group.  That group can then have simple_child
- * children of its own.
- */
-
-static struct config_group *group_children_make_group(struct config_group *group, const char *name)
-{
-       struct simple_children *simple_children;
-
-       simple_children = kzalloc(sizeof(struct simple_children),
-                                 GFP_KERNEL);
-       if (!simple_children)
-               return ERR_PTR(-ENOMEM);
-
-       config_group_init_type_name(&simple_children->group, name,
-                                   &simple_children_type);
-
-       return &simple_children->group;
-}
-
-static struct configfs_attribute group_children_attr_description = {
-       .ca_owner = THIS_MODULE,
-       .ca_name = "description",
-       .ca_mode = S_IRUGO,
-};
-
-static struct configfs_attribute *group_children_attrs[] = {
-       &group_children_attr_description,
-       NULL,
-};
-
-static ssize_t group_children_attr_show(struct config_item *item,
-                                       struct configfs_attribute *attr,
-                                       char *page)
-{
-       return sprintf(page,
-"[03-group-children]\n"
-"\n"
-"This subsystem allows the creation of child config_groups.  These\n"
-"groups are like the subsystem simple-children.\n");
-}
-
-static struct configfs_item_operations group_children_item_ops = {
-       .show_attribute = group_children_attr_show,
-};
-
-/*
- * Note that, since no extra work is required on ->drop_item(),
- * no ->drop_item() is provided.
- */
-static struct configfs_group_operations group_children_group_ops = {
-       .make_group     = group_children_make_group,
-};
-
-static struct config_item_type group_children_type = {
-       .ct_item_ops    = &group_children_item_ops,
-       .ct_group_ops   = &group_children_group_ops,
-       .ct_attrs       = group_children_attrs,
-       .ct_owner       = THIS_MODULE,
-};
-
-static struct configfs_subsystem group_children_subsys = {
-       .su_group = {
-               .cg_item = {
-                       .ci_namebuf = "03-group-children",
-                       .ci_type = &group_children_type,
-               },
-       },
-};
-
-/* ----------------------------------------------------------------- */
-
-/*
- * We're now done with our subsystem definitions.
- * For convenience in this module, here's a list of them all.  It
- * allows the init function to easily register them.  Most modules
- * will only have one subsystem, and will only call register_subsystem
- * on it directly.
- */
-static struct configfs_subsystem *example_subsys[] = {
-       &childless_subsys.subsys,
-       &simple_children_subsys,
-       &group_children_subsys,
-       NULL,
-};
-
-static int __init configfs_example_init(void)
-{
-       int ret;
-       int i;
-       struct configfs_subsystem *subsys;
-
-       for (i = 0; example_subsys[i]; i++) {
-               subsys = example_subsys[i];
-
-               config_group_init(&subsys->su_group);
-               mutex_init(&subsys->su_mutex);
-               ret = configfs_register_subsystem(subsys);
-               if (ret) {
-                       printk(KERN_ERR "Error %d while registering subsystem %s\n",
-                              ret,
-                              subsys->su_group.cg_item.ci_namebuf);
-                       goto out_unregister;
-               }
-       }
-
-       return 0;
-
-out_unregister:
-       for (i--; i >= 0; i--)
-               configfs_unregister_subsystem(example_subsys[i]);
-
-       return ret;
-}
-
-static void __exit configfs_example_exit(void)
-{
-       int i;
-
-       for (i = 0; example_subsys[i]; i++)
-               configfs_unregister_subsystem(example_subsys[i]);
-}
-
-module_init(configfs_example_init);
-module_exit(configfs_example_exit);
-MODULE_LICENSE("GPL");
index 106ca58..d39099e 100644 (file)
@@ -65,7 +65,6 @@ static int fill_read_buffer(struct dentry * dentry, struct configfs_buffer * buf
 {
        struct configfs_attribute * attr = to_attr(dentry);
        struct config_item * item = to_item(dentry->d_parent);
-       struct configfs_item_operations * ops = buffer->ops;
        int ret = 0;
        ssize_t count;
 
@@ -74,10 +73,7 @@ static int fill_read_buffer(struct dentry * dentry, struct configfs_buffer * buf
        if (!buffer->page)
                return -ENOMEM;
 
-       if (ops->show_attribute)
-               count = ops->show_attribute(item, attr, buffer->page);
-       else
-               count = attr->show(item, buffer->page);
+       count = attr->show(item, buffer->page);
 
        buffer->needs_read_fill = 0;
        BUG_ON(count > (ssize_t)SIMPLE_ATTR_SIZE);
@@ -175,10 +171,7 @@ flush_write_buffer(struct dentry * dentry, struct configfs_buffer * buffer, size
 {
        struct configfs_attribute * attr = to_attr(dentry);
        struct config_item * item = to_item(dentry->d_parent);
-       struct configfs_item_operations * ops = buffer->ops;
 
-       if (ops->store_attribute)
-               return ops->store_attribute(item, attr, buffer->page, count);
        return attr->store(item, buffer->page, count);
 }
 
@@ -243,8 +236,7 @@ static int check_perm(struct inode * inode, struct file * file)
         * and we must have a store method.
         */
        if (file->f_mode & FMODE_WRITE) {
-               if (!(inode->i_mode & S_IWUGO) ||
-                   (!ops->store_attribute && !attr->store))
+               if (!(inode->i_mode & S_IWUGO) || !attr->store)
                        goto Eaccess;
 
        }
@@ -254,8 +246,7 @@ static int check_perm(struct inode * inode, struct file * file)
         * must be a show method for it.
         */
        if (file->f_mode & FMODE_READ) {
-               if (!(inode->i_mode & S_IRUGO) ||
-                   (!ops->show_attribute && !attr->show))
+               if (!(inode->i_mode & S_IRUGO) || !attr->show)
                        goto Eaccess;
        }
 
index 85e9956..a8a335b 100644 (file)
@@ -155,86 +155,6 @@ static struct configfs_attribute _pfx##attr_##_name = {    \
 }
 
 /*
- * Users often need to create attribute structures for their configurable
- * attributes, containing a configfs_attribute member and function pointers
- * for the show() and store() operations on that attribute. If they don't
- * need anything else on the extended attribute structure, they can use
- * this macro to define it  The argument _item is the name of the
- * config_item structure.
- */
-#define CONFIGFS_ATTR_STRUCT(_item)                                    \
-struct _item##_attribute {                                             \
-       struct configfs_attribute attr;                                 \
-       ssize_t (*show)(struct _item *, char *);                        \
-       ssize_t (*store)(struct _item *, const char *, size_t);         \
-}
-
-/*
- * With the extended attribute structure, users can use this macro
- * (similar to sysfs' __ATTR) to make defining attributes easier.
- * An example:
- * #define MYITEM_ATTR(_name, _mode, _show, _store)    \
- * struct myitem_attribute childless_attr_##_name =    \
- *         __CONFIGFS_ATTR(_name, _mode, _show, _store)
- */
-#define __CONFIGFS_ATTR(_name, _mode, _show, _store)                   \
-{                                                                      \
-       .attr   = {                                                     \
-                       .ca_name = __stringify(_name),                  \
-                       .ca_mode = _mode,                               \
-                       .ca_owner = THIS_MODULE,                        \
-       },                                                              \
-       .show   = _show,                                                \
-       .store  = _store,                                               \
-}
-/* Here is a readonly version, only requiring a show() operation */
-#define __CONFIGFS_ATTR_RO(_name, _show)                               \
-{                                                                      \
-       .attr   = {                                                     \
-                       .ca_name = __stringify(_name),                  \
-                       .ca_mode = 0444,                                \
-                       .ca_owner = THIS_MODULE,                        \
-       },                                                              \
-       .show   = _show,                                                \
-}
-
-/*
- * With these extended attributes, the simple show_attribute() and
- * store_attribute() operations need to call the show() and store() of the
- * attributes.  This is a common pattern, so we provide a macro to define
- * them.  The argument _item is the name of the config_item structure.
- * This macro expects the attributes to be named "struct <name>_attribute"
- * and the function to_<name>() to exist;
- */
-#define CONFIGFS_ATTR_OPS(_item)                                       \
-static ssize_t _item##_attr_show(struct config_item *item,             \
-                                struct configfs_attribute *attr,       \
-                                char *page)                            \
-{                                                                      \
-       struct _item *_item = to_##_item(item);                         \
-       struct _item##_attribute *_item##_attr =                        \
-               container_of(attr, struct _item##_attribute, attr);     \
-       ssize_t ret = 0;                                                \
-                                                                       \
-       if (_item##_attr->show)                                         \
-               ret = _item##_attr->show(_item, page);                  \
-       return ret;                                                     \
-}                                                                      \
-static ssize_t _item##_attr_store(struct config_item *item,            \
-                                 struct configfs_attribute *attr,      \
-                                 const char *page, size_t count)       \
-{                                                                      \
-       struct _item *_item = to_##_item(item);                         \
-       struct _item##_attribute *_item##_attr =                        \
-               container_of(attr, struct _item##_attribute, attr);     \
-       ssize_t ret = -EINVAL;                                          \
-                                                                       \
-       if (_item##_attr->store)                                        \
-               ret = _item##_attr->store(_item, page, count);          \
-       return ret;                                                     \
-}
-
-/*
  * If allow_link() exists, the item can symlink(2) out to other
  * items.  If the item is a group, it may support mkdir(2).
  * Groups supply one of make_group() and make_item().  If the
@@ -250,8 +170,6 @@ static ssize_t _item##_attr_store(struct config_item *item,         \
  */
 struct configfs_item_operations {
        void (*release)(struct config_item *);
-       ssize_t (*show_attribute)(struct config_item *, struct configfs_attribute *,char *);
-       ssize_t (*store_attribute)(struct config_item *,struct configfs_attribute *,const char *, size_t);
        int (*allow_link)(struct config_item *src, struct config_item *target);
        int (*drop_link)(struct config_item *src, struct config_item *target);
 };
index 224ebb4..d54f28c 100644 (file)
@@ -70,4 +70,10 @@ config SAMPLE_LIVEPATCH
          Builds a sample live patch that replaces the procfs handler
          for /proc/cmdline to print "this has been live patched".
 
+config SAMPLE_CONFIGFS
+       tristate "Build configfs patching sample -- loadable modules only"
+       depends on CONFIGFS_FS && m
+       help
+         Builds a sample configfs interface.
+
 endif # SAMPLES
index f00257b..48001d7 100644 (file)
@@ -1,4 +1,5 @@
 # Makefile for Linux samples code
 
 obj-$(CONFIG_SAMPLES)  += kobject/ kprobes/ trace_events/ livepatch/ \
-                          hw_breakpoint/ kfifo/ kdb/ hidraw/ rpmsg/ seccomp/
+                          hw_breakpoint/ kfifo/ kdb/ hidraw/ rpmsg/ seccomp/ \
+                          configfs/
diff --git a/samples/configfs/Makefile b/samples/configfs/Makefile
new file mode 100644 (file)
index 0000000..a9afd99
--- /dev/null
@@ -0,0 +1,2 @@
+
+obj-$(CONFIG_SAMPLE_CONFIGFS) += configfs_sample.o
@@ -54,18 +54,13 @@ struct childless {
 
 static inline struct childless *to_childless(struct config_item *item)
 {
-       return item ? container_of(to_configfs_subsystem(to_config_group(item)), struct childless, subsys) : NULL;
+       return item ? container_of(to_configfs_subsystem(to_config_group(item)),
+                       struct childless, subsys) : NULL;
 }
 
-CONFIGFS_ATTR_STRUCT(childless);
-#define CHILDLESS_ATTR(_name, _mode, _show, _store)    \
-struct childless_attribute childless_attr_##_name = __CONFIGFS_ATTR(_name, _mode, _show, _store)
-#define CHILDLESS_ATTR_RO(_name, _show)        \
-struct childless_attribute childless_attr_##_name = __CONFIGFS_ATTR_RO(_name, _show);
-
-static ssize_t childless_showme_read(struct childless *childless,
-                                    char *page)
+static ssize_t childless_showme_show(struct config_item *item, char *page)
 {
+       struct childless *childless = to_childless(item);
        ssize_t pos;
 
        pos = sprintf(page, "%d\n", childless->showme);
@@ -74,16 +69,15 @@ static ssize_t childless_showme_read(struct childless *childless,
        return pos;
 }
 
-static ssize_t childless_storeme_read(struct childless *childless,
-                                     char *page)
+static ssize_t childless_storeme_show(struct config_item *item, char *page)
 {
-       return sprintf(page, "%d\n", childless->storeme);
+       return sprintf(page, "%d\n", to_childless(item)->storeme);
 }
 
-static ssize_t childless_storeme_write(struct childless *childless,
-                                      const char *page,
-                                      size_t count)
+static ssize_t childless_storeme_store(struct config_item *item,
+               const char *page, size_t count)
 {
+       struct childless *childless = to_childless(item);
        unsigned long tmp;
        char *p = (char *) page;
 
@@ -99,8 +93,7 @@ static ssize_t childless_storeme_write(struct childless *childless,
        return count;
 }
 
-static ssize_t childless_description_read(struct childless *childless,
-                                         char *page)
+static ssize_t childless_description_show(struct config_item *item, char *page)
 {
        return sprintf(page,
 "[01-childless]\n"
@@ -111,26 +104,18 @@ static ssize_t childless_description_read(struct childless *childless,
 "than a directory in /proc.\n");
 }
 
-CHILDLESS_ATTR_RO(showme, childless_showme_read);
-CHILDLESS_ATTR(storeme, S_IRUGO | S_IWUSR, childless_storeme_read,
-              childless_storeme_write);
-CHILDLESS_ATTR_RO(description, childless_description_read);
+CONFIGFS_ATTR_RO(childless_, showme);
+CONFIGFS_ATTR(childless_, storeme);
+CONFIGFS_ATTR_RO(childless_, description);
 
 static struct configfs_attribute *childless_attrs[] = {
-       &childless_attr_showme.attr,
-       &childless_attr_storeme.attr,
-       &childless_attr_description.attr,
+       &childless_attr_showme,
+       &childless_attr_storeme,
+       &childless_attr_description,
        NULL,
 };
 
-CONFIGFS_ATTR_OPS(childless);
-static struct configfs_item_operations childless_item_ops = {
-       .show_attribute         = childless_attr_show,
-       .store_attribute        = childless_attr_store,
-};
-
 static struct config_item_type childless_type = {
-       .ct_item_ops    = &childless_item_ops,
        .ct_attrs       = childless_attrs,
        .ct_owner       = THIS_MODULE,
 };
@@ -168,32 +153,13 @@ static inline struct simple_child *to_simple_child(struct config_item *item)
        return item ? container_of(item, struct simple_child, item) : NULL;
 }
 
-static struct configfs_attribute simple_child_attr_storeme = {
-       .ca_owner = THIS_MODULE,
-       .ca_name = "storeme",
-       .ca_mode = S_IRUGO | S_IWUSR,
-};
-
-static struct configfs_attribute *simple_child_attrs[] = {
-       &simple_child_attr_storeme,
-       NULL,
-};
-
-static ssize_t simple_child_attr_show(struct config_item *item,
-                                     struct configfs_attribute *attr,
-                                     char *page)
+static ssize_t simple_child_storeme_show(struct config_item *item, char *page)
 {
-       ssize_t count;
-       struct simple_child *simple_child = to_simple_child(item);
-
-       count = sprintf(page, "%d\n", simple_child->storeme);
-
-       return count;
+       return sprintf(page, "%d\n", to_simple_child(item)->storeme);
 }
 
-static ssize_t simple_child_attr_store(struct config_item *item,
-                                      struct configfs_attribute *attr,
-                                      const char *page, size_t count)
+static ssize_t simple_child_storeme_store(struct config_item *item,
+               const char *page, size_t count)
 {
        struct simple_child *simple_child = to_simple_child(item);
        unsigned long tmp;
@@ -211,6 +177,13 @@ static ssize_t simple_child_attr_store(struct config_item *item,
        return count;
 }
 
+CONFIGFS_ATTR(simple_child_, storeme);
+
+static struct configfs_attribute *simple_child_attrs[] = {
+       &simple_child_attr_storeme,
+       NULL,
+};
+
 static void simple_child_release(struct config_item *item)
 {
        kfree(to_simple_child(item));
@@ -218,8 +191,6 @@ static void simple_child_release(struct config_item *item)
 
 static struct configfs_item_operations simple_child_item_ops = {
        .release                = simple_child_release,
-       .show_attribute         = simple_child_attr_show,
-       .store_attribute        = simple_child_attr_store,
 };
 
 static struct config_item_type simple_child_type = {
@@ -235,10 +206,12 @@ struct simple_children {
 
 static inline struct simple_children *to_simple_children(struct config_item *item)
 {
-       return item ? container_of(to_config_group(item), struct simple_children, group) : NULL;
+       return item ? container_of(to_config_group(item),
+                       struct simple_children, group) : NULL;
 }
 
-static struct config_item *simple_children_make_item(struct config_group *group, const char *name)
+static struct config_item *simple_children_make_item(struct config_group *group,
+               const char *name)
 {
        struct simple_child *simple_child;
 
@@ -254,20 +227,8 @@ static struct config_item *simple_children_make_item(struct config_group *group,
        return &simple_child->item;
 }
 
-static struct configfs_attribute simple_children_attr_description = {
-       .ca_owner = THIS_MODULE,
-       .ca_name = "description",
-       .ca_mode = S_IRUGO,
-};
-
-static struct configfs_attribute *simple_children_attrs[] = {
-       &simple_children_attr_description,
-       NULL,
-};
-
-static ssize_t simple_children_attr_show(struct config_item *item,
-                                        struct configfs_attribute *attr,
-                                        char *page)
+static ssize_t simple_children_description_show(struct config_item *item,
+               char *page)
 {
        return sprintf(page,
 "[02-simple-children]\n"
@@ -276,6 +237,13 @@ static ssize_t simple_children_attr_show(struct config_item *item,
 "items have only one attribute that is readable and writeable.\n");
 }
 
+CONFIGFS_ATTR_RO(simple_children_, description);
+
+static struct configfs_attribute *simple_children_attrs[] = {
+       &simple_children_attr_description,
+       NULL,
+};
+
 static void simple_children_release(struct config_item *item)
 {
        kfree(to_simple_children(item));
@@ -283,7 +251,6 @@ static void simple_children_release(struct config_item *item)
 
 static struct configfs_item_operations simple_children_item_ops = {
        .release        = simple_children_release,
-       .show_attribute = simple_children_attr_show,
 };
 
 /*
@@ -323,7 +290,8 @@ static struct configfs_subsystem simple_children_subsys = {
  * children of its own.
  */
 
-static struct config_group *group_children_make_group(struct config_group *group, const char *name)
+static struct config_group *group_children_make_group(
+               struct config_group *group, const char *name)
 {
        struct simple_children *simple_children;
 
@@ -338,20 +306,8 @@ static struct config_group *group_children_make_group(struct config_group *group
        return &simple_children->group;
 }
 
-static struct configfs_attribute group_children_attr_description = {
-       .ca_owner = THIS_MODULE,
-       .ca_name = "description",
-       .ca_mode = S_IRUGO,
-};
-
-static struct configfs_attribute *group_children_attrs[] = {
-       &group_children_attr_description,
-       NULL,
-};
-
-static ssize_t group_children_attr_show(struct config_item *item,
-                                       struct configfs_attribute *attr,
-                                       char *page)
+static ssize_t group_children_description_show(struct config_item *item,
+               char *page)
 {
        return sprintf(page,
 "[03-group-children]\n"
@@ -360,8 +316,11 @@ static ssize_t group_children_attr_show(struct config_item *item,
 "groups are like the subsystem simple-children.\n");
 }
 
-static struct configfs_item_operations group_children_item_ops = {
-       .show_attribute = group_children_attr_show,
+CONFIGFS_ATTR_RO(group_children_, description);
+
+static struct configfs_attribute *group_children_attrs[] = {
+       &group_children_attr_description,
+       NULL,
 };
 
 /*
@@ -373,7 +332,6 @@ static struct configfs_group_operations group_children_group_ops = {
 };
 
 static struct config_item_type group_children_type = {
-       .ct_item_ops    = &group_children_item_ops,
        .ct_group_ops   = &group_children_group_ops,
        .ct_attrs       = group_children_attrs,
        .ct_owner       = THIS_MODULE,