alistair23-linux/fs/jffs2/xattr.h
Jean-Christophe DUBOIS 8c5a036640 jffs2: allow to complete xattr integrity check on first GC scan
Unlike file data integrity the xattr data integrity was not checked
before some explicit access to the attribute was made.

This could leave in the system a number of corrupted extended attributes
which will be detected only at access time and possibly at a very late
time compared to the time the corruption actually happened.

This patch adds the ability to check for extended attribute integrity
on first GC scan pass (similar to file data integrity check). This allows
for all present attributes to be completly verified before any use of them.

In order to work correctly this patch also needs the patch allowing
JFFS2 to discriminate between recoverable and non recoverable errors
on extended attributes.

Signed-off-by: Jean-Christophe DUBOIS <jcd@tribudubois.net>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2012-05-13 23:32:36 -05:00

134 lines
4.3 KiB
C

/*
* JFFS2 -- Journalling Flash File System, Version 2.
*
* Copyright © 2006 NEC Corporation
*
* Created by KaiGai Kohei <kaigai@ak.jp.nec.com>
*
* For licensing information, see the file 'LICENCE' in this directory.
*
*/
#ifndef _JFFS2_FS_XATTR_H_
#define _JFFS2_FS_XATTR_H_
#include <linux/xattr.h>
#include <linux/list.h>
#define JFFS2_XFLAGS_HOT (0x01) /* This datum is HOT */
#define JFFS2_XFLAGS_BIND (0x02) /* This datum is not reclaimed */
#define JFFS2_XFLAGS_DEAD (0x40) /* This datum is already dead */
#define JFFS2_XFLAGS_INVALID (0x80) /* This datum contains crc error */
struct jffs2_xattr_datum
{
void *always_null;
struct jffs2_raw_node_ref *node;
uint8_t class;
uint8_t flags;
uint16_t xprefix; /* see JFFS2_XATTR_PREFIX_* */
struct list_head xindex; /* chained from c->xattrindex[n] */
atomic_t refcnt; /* # of xattr_ref refers this */
uint32_t xid;
uint32_t version;
uint32_t data_crc;
uint32_t hashkey;
char *xname; /* XATTR name without prefix */
uint32_t name_len; /* length of xname */
char *xvalue; /* XATTR value */
uint32_t value_len; /* length of xvalue */
};
struct jffs2_inode_cache;
struct jffs2_xattr_ref
{
void *always_null;
struct jffs2_raw_node_ref *node;
uint8_t class;
uint8_t flags; /* Currently unused */
u16 unused;
uint32_t xseqno;
union {
struct jffs2_inode_cache *ic; /* reference to jffs2_inode_cache */
uint32_t ino; /* only used in scanning/building */
};
union {
struct jffs2_xattr_datum *xd; /* reference to jffs2_xattr_datum */
uint32_t xid; /* only used in sccanning/building */
};
struct jffs2_xattr_ref *next; /* chained from ic->xref_list */
};
#define XREF_DELETE_MARKER (0x00000001)
static inline int is_xattr_ref_dead(struct jffs2_xattr_ref *ref)
{
return ((ref->xseqno & XREF_DELETE_MARKER) != 0);
}
#ifdef CONFIG_JFFS2_FS_XATTR
extern void jffs2_init_xattr_subsystem(struct jffs2_sb_info *c);
extern void jffs2_build_xattr_subsystem(struct jffs2_sb_info *c);
extern void jffs2_clear_xattr_subsystem(struct jffs2_sb_info *c);
extern struct jffs2_xattr_datum *jffs2_setup_xattr_datum(struct jffs2_sb_info *c,
uint32_t xid, uint32_t version);
extern void jffs2_xattr_do_crccheck_inode(struct jffs2_sb_info *c, struct jffs2_inode_cache *ic);
extern void jffs2_xattr_delete_inode(struct jffs2_sb_info *c, struct jffs2_inode_cache *ic);
extern void jffs2_xattr_free_inode(struct jffs2_sb_info *c, struct jffs2_inode_cache *ic);
extern int jffs2_garbage_collect_xattr_datum(struct jffs2_sb_info *c, struct jffs2_xattr_datum *xd,
struct jffs2_raw_node_ref *raw);
extern int jffs2_garbage_collect_xattr_ref(struct jffs2_sb_info *c, struct jffs2_xattr_ref *ref,
struct jffs2_raw_node_ref *raw);
extern int jffs2_verify_xattr(struct jffs2_sb_info *c);
extern void jffs2_release_xattr_datum(struct jffs2_sb_info *c, struct jffs2_xattr_datum *xd);
extern void jffs2_release_xattr_ref(struct jffs2_sb_info *c, struct jffs2_xattr_ref *ref);
extern int do_jffs2_getxattr(struct inode *inode, int xprefix, const char *xname,
char *buffer, size_t size);
extern int do_jffs2_setxattr(struct inode *inode, int xprefix, const char *xname,
const char *buffer, size_t size, int flags);
extern const struct xattr_handler *jffs2_xattr_handlers[];
extern const struct xattr_handler jffs2_user_xattr_handler;
extern const struct xattr_handler jffs2_trusted_xattr_handler;
extern ssize_t jffs2_listxattr(struct dentry *, char *, size_t);
#define jffs2_getxattr generic_getxattr
#define jffs2_setxattr generic_setxattr
#define jffs2_removexattr generic_removexattr
#else
#define jffs2_init_xattr_subsystem(c)
#define jffs2_build_xattr_subsystem(c)
#define jffs2_clear_xattr_subsystem(c)
#define jffs2_xattr_do_crccheck_inode(c, ic)
#define jffs2_xattr_delete_inode(c, ic)
#define jffs2_xattr_free_inode(c, ic)
#define jffs2_verify_xattr(c) (1)
#define jffs2_xattr_handlers NULL
#define jffs2_listxattr NULL
#define jffs2_getxattr NULL
#define jffs2_setxattr NULL
#define jffs2_removexattr NULL
#endif /* CONFIG_JFFS2_FS_XATTR */
#ifdef CONFIG_JFFS2_FS_SECURITY
extern int jffs2_init_security(struct inode *inode, struct inode *dir,
const struct qstr *qstr);
extern const struct xattr_handler jffs2_security_xattr_handler;
#else
#define jffs2_init_security(inode,dir,qstr) (0)
#endif /* CONFIG_JFFS2_FS_SECURITY */
#endif /* _JFFS2_FS_XATTR_H_ */