diff options
Diffstat (limited to 'include')
| -rw-r--r-- | include/linux/configfs.h | 205 | ||||
| -rw-r--r-- | include/linux/fs.h | 31 | ||||
| -rw-r--r-- | include/linux/writeback.h | 6 |
3 files changed, 236 insertions, 6 deletions
diff --git a/include/linux/configfs.h b/include/linux/configfs.h new file mode 100644 index 00000000000..acffb8c9073 --- /dev/null +++ b/include/linux/configfs.h @@ -0,0 +1,205 @@ +/* -*- mode: c; c-basic-offset: 8; -*- + * vim: noexpandtab sw=8 ts=8 sts=0: + * + * configfs.h - definitions for the device driver filesystem + * + * 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 + * + * Based on kobject.h: + * Copyright (c) 2002-2003 Patrick Mochel + * Copyright (c) 2002-2003 Open Source Development Labs + * + * configfs Copyright (C) 2005 Oracle. All rights reserved. + * + * Please read Documentation/filesystems/configfs.txt before using the + * configfs interface, ESPECIALLY the parts about reference counts and + * item destructors. + */ + +#ifndef _CONFIGFS_H_ +#define _CONFIGFS_H_ + +#ifdef __KERNEL__ + +#include <linux/types.h> +#include <linux/list.h> +#include <linux/kref.h> + +#include <asm/atomic.h> +#include <asm/semaphore.h> + +#define CONFIGFS_ITEM_NAME_LEN 20 + +struct module; + +struct configfs_item_operations; +struct configfs_group_operations; +struct configfs_attribute; +struct configfs_subsystem; + +struct config_item { + char *ci_name; + char ci_namebuf[CONFIGFS_ITEM_NAME_LEN]; + struct kref ci_kref; + struct list_head ci_entry; + struct config_item *ci_parent; + struct config_group *ci_group; + struct config_item_type *ci_type; + struct dentry *ci_dentry; +}; + +extern int config_item_set_name(struct config_item *, const char *, ...); + +static inline char *config_item_name(struct config_item * item) +{ + return item->ci_name; +} + +extern void config_item_init(struct config_item *); +extern void config_item_init_type_name(struct config_item *item, + const char *name, + struct config_item_type *type); +extern void config_item_cleanup(struct config_item *); + +extern struct config_item * config_item_get(struct config_item *); +extern void config_item_put(struct config_item *); + +struct config_item_type { + struct module *ct_owner; + struct configfs_item_operations *ct_item_ops; + struct configfs_group_operations *ct_group_ops; + struct configfs_attribute **ct_attrs; +}; + + +/** + * group - a group of config_items of a specific type, belonging + * to a specific subsystem. + */ + +struct config_group { + struct config_item cg_item; + struct list_head cg_children; + struct configfs_subsystem *cg_subsys; + struct config_group **default_groups; +}; + + +extern void config_group_init(struct config_group *group); +extern void config_group_init_type_name(struct config_group *group, + const char *name, + struct config_item_type *type); + + +static inline struct config_group *to_config_group(struct config_item *item) +{ + return item ? container_of(item,struct config_group,cg_item) : NULL; +} + +static inline struct config_group *config_group_get(struct config_group *group) +{ + return group ? to_config_group(config_item_get(&group->cg_item)) : NULL; +} + +static inline void config_group_put(struct config_group *group) +{ + config_item_put(&group->cg_item); +} + +extern struct config_item *config_group_find_obj(struct config_group *, const char *); + + +struct configfs_attribute { + char *ca_name; + struct module *ca_owner; + mode_t ca_mode; +}; + + +/* + * 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 + * group supports make_group(), one can create group children. If it + * supports make_item(), one can create config_item children. If it has + * default_groups on group->default_groups, it has automatically created + * group children. default_groups may coexist alongsize make_group() or + * make_item(), but if the group wishes to have only default_groups + * children (disallowing mkdir(2)), it need not provide either function. + * If the group has commit(), it supports pending and commited (active) + * items. + */ +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); +}; + +struct configfs_group_operations { + struct config_item *(*make_item)(struct config_group *group, const char *name); + struct config_group *(*make_group)(struct config_group *group, const char *name); + int (*commit_item)(struct config_item *item); + void (*drop_item)(struct config_group *group, struct config_item *item); +}; + + + +/** + * Use these macros to make defining attributes easier. See include/linux/device.h + * for examples.. + */ + +#if 0 +#define __ATTR(_name,_mode,_show,_store) { \ + .attr = {.ca_name = __stringify(_name), .ca_mode = _mode, .ca_owner = THIS_MODULE }, \ + .show = _show, \ + .store = _store, \ +} + +#define __ATTR_RO(_name) { \ + .attr = { .ca_name = __stringify(_name), .ca_mode = 0444, .ca_owner = THIS_MODULE }, \ + .show = _name##_show, \ +} + +#define __ATTR_NULL { .attr = { .name = NULL } } + +#define attr_name(_attr) (_attr).attr.name +#endif + + +struct configfs_subsystem { + struct config_group su_group; + struct semaphore su_sem; +}; + +static inline struct configfs_subsystem *to_configfs_subsystem(struct config_group *group) +{ + return group ? + container_of(group, struct configfs_subsystem, su_group) : + NULL; +} + +int configfs_register_subsystem(struct configfs_subsystem *subsys); +void configfs_unregister_subsystem(struct configfs_subsystem *subsys); + +#endif /* __KERNEL__ */ + +#endif /* _CONFIGFS_H_ */ diff --git a/include/linux/fs.h b/include/linux/fs.h index cc35b6ac778..ed9a41a71e8 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -302,6 +302,37 @@ struct iattr { */ #include <linux/quota.h> +/** + * enum positive_aop_returns - aop return codes with specific semantics + * + * @AOP_WRITEPAGE_ACTIVATE: Informs the caller that page writeback has + * completed, that the page is still locked, and + * should be considered active. The VM uses this hint + * to return the page to the active list -- it won't + * be a candidate for writeback again in the near + * future. Other callers must be careful to unlock + * the page if they get this return. Returned by + * writepage(); + * + * @AOP_TRUNCATED_PAGE: The AOP method that was handed a locked page has + * unlocked it and the page might have been truncated. + * The caller should back up to acquiring a new page and + * trying again. The aop will be taking reasonable + * precautions not to livelock. If the caller held a page + * reference, it should drop it before retrying. Returned + * by readpage(), prepare_write(), and commit_write(). + * + * address_space_operation functions return these large constants to indicate + * special semantics to the caller. These are much larger than the bytes in a + * page to allow for functions that return the number of bytes operated on in a + * given page. + */ + +enum positive_aop_returns { + AOP_WRITEPAGE_ACTIVATE = 0x80000, + AOP_TRUNCATED_PAGE = 0x80001, +}; + /* * oh the beauties of C type declarations. */ diff --git a/include/linux/writeback.h b/include/linux/writeback.h index 343d883d69c..64a36ba43b2 100644 --- a/include/linux/writeback.h +++ b/include/linux/writeback.h @@ -60,12 +60,6 @@ struct writeback_control { }; /* - * ->writepage() return values (make these much larger than a pagesize, in - * case some fs is returning number-of-bytes-written from writepage) - */ -#define WRITEPAGE_ACTIVATE 0x80000 /* IO was not started: activate page */ - -/* * fs/fs-writeback.c */ void writeback_inodes(struct writeback_control *wbc); |