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Diffstat (limited to 'fs/f2fs/xattr.h')
| -rw-r--r-- | fs/f2fs/xattr.h | 145 |
1 files changed, 145 insertions, 0 deletions
diff --git a/fs/f2fs/xattr.h b/fs/f2fs/xattr.h new file mode 100644 index 000000000000..29b0a08e1e14 --- /dev/null +++ b/fs/f2fs/xattr.h @@ -0,0 +1,145 @@ +/** + * fs/f2fs/xattr.h + * + * Copyright (c) 2012 Samsung Electronics Co., Ltd. + * http://www.samsung.com/ + * + * Portions of this code from linux/fs/ext2/xattr.h + * + * On-disk format of extended attributes for the ext2 filesystem. + * + * (C) 2001 Andreas Gruenbacher, <a.gruenbacher@computer.org> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ +#ifndef __F2FS_XATTR_H__ +#define __F2FS_XATTR_H__ + +#include <linux/init.h> +#include <linux/xattr.h> + +/* Magic value in attribute blocks */ +#define F2FS_XATTR_MAGIC 0xF2F52011 + +/* Maximum number of references to one attribute block */ +#define F2FS_XATTR_REFCOUNT_MAX 1024 + +/* Name indexes */ +#define F2FS_SYSTEM_ADVISE_PREFIX "system.advise" +#define F2FS_XATTR_INDEX_USER 1 +#define F2FS_XATTR_INDEX_POSIX_ACL_ACCESS 2 +#define F2FS_XATTR_INDEX_POSIX_ACL_DEFAULT 3 +#define F2FS_XATTR_INDEX_TRUSTED 4 +#define F2FS_XATTR_INDEX_LUSTRE 5 +#define F2FS_XATTR_INDEX_SECURITY 6 +#define F2FS_XATTR_INDEX_ADVISE 7 + +struct f2fs_xattr_header { + __le32 h_magic; /* magic number for identification */ + __le32 h_refcount; /* reference count */ + __u32 h_reserved[4]; /* zero right now */ +}; + +struct f2fs_xattr_entry { + __u8 e_name_index; + __u8 e_name_len; + __le16 e_value_size; /* size of attribute value */ + char e_name[0]; /* attribute name */ +}; + +#define XATTR_HDR(ptr) ((struct f2fs_xattr_header *)(ptr)) +#define XATTR_ENTRY(ptr) ((struct f2fs_xattr_entry *)(ptr)) +#define XATTR_FIRST_ENTRY(ptr) (XATTR_ENTRY(XATTR_HDR(ptr)+1)) +#define XATTR_ROUND (3) + +#define XATTR_ALIGN(size) ((size + XATTR_ROUND) & ~XATTR_ROUND) + +#define ENTRY_SIZE(entry) (XATTR_ALIGN(sizeof(struct f2fs_xattr_entry) + \ + entry->e_name_len + le16_to_cpu(entry->e_value_size))) + +#define XATTR_NEXT_ENTRY(entry) ((struct f2fs_xattr_entry *)((char *)(entry) +\ + ENTRY_SIZE(entry))) + +#define IS_XATTR_LAST_ENTRY(entry) (*(__u32 *)(entry) == 0) + +#define list_for_each_xattr(entry, addr) \ + for (entry = XATTR_FIRST_ENTRY(addr);\ + !IS_XATTR_LAST_ENTRY(entry);\ + entry = XATTR_NEXT_ENTRY(entry)) + + +#define MIN_OFFSET XATTR_ALIGN(PAGE_SIZE - \ + sizeof(struct node_footer) - \ + sizeof(__u32)) + +#define MAX_VALUE_LEN (MIN_OFFSET - sizeof(struct f2fs_xattr_header) - \ + sizeof(struct f2fs_xattr_entry)) + +/** + * On-disk structure of f2fs_xattr + * We use only 1 block for xattr. + * + * +--------------------+ + * | f2fs_xattr_header | + * | | + * +--------------------+ + * | f2fs_xattr_entry | + * | .e_name_index = 1 | + * | .e_name_len = 3 | + * | .e_value_size = 14 | + * | .e_name = "foo" | + * | "value_of_xattr" |<- value_offs = e_name + e_name_len + * +--------------------+ + * | f2fs_xattr_entry | + * | .e_name_index = 4 | + * | .e_name = "bar" | + * +--------------------+ + * | | + * | Free | + * | | + * +--------------------+<- MIN_OFFSET + * | node_footer | + * | (nid, ino, offset) | + * +--------------------+ + * + **/ + +#ifdef CONFIG_F2FS_FS_XATTR +extern const struct xattr_handler f2fs_xattr_user_handler; +extern const struct xattr_handler f2fs_xattr_trusted_handler; +extern const struct xattr_handler f2fs_xattr_acl_access_handler; +extern const struct xattr_handler f2fs_xattr_acl_default_handler; +extern const struct xattr_handler f2fs_xattr_advise_handler; + +extern const struct xattr_handler *f2fs_xattr_handlers[]; + +extern int f2fs_setxattr(struct inode *inode, int name_index, const char *name, + const void *value, size_t value_len); +extern int f2fs_getxattr(struct inode *inode, int name_index, const char *name, + void *buffer, size_t buffer_size); +extern ssize_t f2fs_listxattr(struct dentry *dentry, char *buffer, + size_t buffer_size); + +#else + +#define f2fs_xattr_handlers NULL +static inline int f2fs_setxattr(struct inode *inode, int name_index, + const char *name, const void *value, size_t value_len) +{ + return -EOPNOTSUPP; +} +static inline int f2fs_getxattr(struct inode *inode, int name_index, + const char *name, void *buffer, size_t buffer_size) +{ + return -EOPNOTSUPP; +} +static inline ssize_t f2fs_listxattr(struct dentry *dentry, char *buffer, + size_t buffer_size) +{ + return -EOPNOTSUPP; +} +#endif + +#endif /* __F2FS_XATTR_H__ */ |