alistair23-linux/fs/f2fs/xattr.h
Chao Yu ba38c27eb9 f2fs: enhance lookup xattr
Previously, in getxattr we will load all entries both in inline xattr and
xattr node block, and then do the lookup in all entries, but our lookup
flow shows low efficiency, since if we can lookup and hit in inline xattr
of inode page cache first, we don't need to load and lookup xattr node
block, which can obviously save cpu time and IO latency.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
[Jaegeuk Kim: initialize NULL to avoid warning]
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2017-02-22 20:24:51 -08:00

159 lines
4.8 KiB
C

/*
* 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_NAME "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
/* Should be same as EXT4_XATTR_INDEX_ENCRYPTION */
#define F2FS_XATTR_INDEX_ENCRYPTION 9
#define F2FS_XATTR_NAME_ENCRYPTION_CONTEXT "c"
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 MAX_XATTR_BLOCK_SIZE (PAGE_SIZE - sizeof(struct node_footer))
#define VALID_XATTR_BLOCK_SIZE (MAX_XATTR_BLOCK_SIZE - sizeof(__u32))
#define MIN_OFFSET(i) XATTR_ALIGN(inline_xattr_size(i) + \
VALID_XATTR_BLOCK_SIZE)
#define MAX_VALUE_LEN(i) (MIN_OFFSET(i) - \
sizeof(struct f2fs_xattr_header) - \
sizeof(struct f2fs_xattr_entry))
/*
* On-disk structure of f2fs_xattr
* We use inline xattrs space + 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_advise_handler;
extern const struct xattr_handler f2fs_xattr_security_handler;
extern const struct xattr_handler *f2fs_xattr_handlers[];
extern int f2fs_setxattr(struct inode *, int, const char *,
const void *, size_t, struct page *, int);
extern int f2fs_getxattr(struct inode *, int, const char *, void *,
size_t, struct page *);
extern ssize_t f2fs_listxattr(struct dentry *, char *, size_t);
#else
#define f2fs_xattr_handlers NULL
static inline int f2fs_setxattr(struct inode *inode, int index,
const char *name, const void *value, size_t size,
struct page *page, int flags)
{
return -EOPNOTSUPP;
}
static inline int f2fs_getxattr(struct inode *inode, int index,
const char *name, void *buffer,
size_t buffer_size, struct page *dpage)
{
return -EOPNOTSUPP;
}
static inline ssize_t f2fs_listxattr(struct dentry *dentry, char *buffer,
size_t buffer_size)
{
return -EOPNOTSUPP;
}
#endif
#ifdef CONFIG_F2FS_FS_SECURITY
extern int f2fs_init_security(struct inode *, struct inode *,
const struct qstr *, struct page *);
#else
static inline int f2fs_init_security(struct inode *inode, struct inode *dir,
const struct qstr *qstr, struct page *ipage)
{
return 0;
}
#endif
#endif /* __F2FS_XATTR_H__ */