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// SPDX-License-Identifier: GPL-2.0
/*
* Copyright (c) 2000,2002-2003,2005 Silicon Graphics, Inc.
* All Rights Reserved.
*/
#ifndef __XFS_ATTR_H__
#define __XFS_ATTR_H__
struct xfs_inode;
struct xfs_da_args;
struct xfs_attr_list_context;
/*
* Large attribute lists are structured around Btrees where all the data
* elements are in the leaf nodes. Attribute names are hashed into an int,
* then that int is used as the index into the Btree. Since the hashval
* of an attribute name may not be unique, we may have duplicate keys.
* The internal links in the Btree are logical block offsets into the file.
*
* Small attribute lists use a different format and are packed as tightly
* as possible so as to fit into the literal area of the inode.
*/
/*========================================================================
* External interfaces
*========================================================================*/
#define ATTR_DONTFOLLOW 0x0001 /* -- ignored, from IRIX -- */
#define ATTR_ROOT 0x0002 /* use attrs in root (trusted) namespace */
#define ATTR_TRUST 0x0004 /* -- unused, from IRIX -- */
#define ATTR_SECURE 0x0008 /* use attrs in security namespace */
#define ATTR_CREATE 0x0010 /* pure create: fail if attr already exists */
#define ATTR_REPLACE 0x0020 /* pure set: fail if attr does not exist */
#define ATTR_KERNOTIME 0x1000 /* [kernel] don't update inode timestamps */
#define ATTR_KERNOVAL 0x2000 /* [kernel] get attr size only, not value */
#define ATTR_INCOMPLETE 0x4000 /* [kernel] return INCOMPLETE attr keys */
#define ATTR_ALLOC 0x8000 /* [kernel] allocate xattr buffer on demand */
#define ATTR_KERNEL_FLAGS \
(ATTR_KERNOTIME | ATTR_KERNOVAL | ATTR_INCOMPLETE | ATTR_ALLOC)
#define XFS_ATTR_FLAGS \
{ ATTR_DONTFOLLOW, "DONTFOLLOW" }, \
{ ATTR_ROOT, "ROOT" }, \
{ ATTR_TRUST, "TRUST" }, \
{ ATTR_SECURE, "SECURE" }, \
{ ATTR_CREATE, "CREATE" }, \
{ ATTR_REPLACE, "REPLACE" }, \
{ ATTR_KERNOTIME, "KERNOTIME" }, \
{ ATTR_KERNOVAL, "KERNOVAL" }, \
{ ATTR_INCOMPLETE, "INCOMPLETE" }, \
{ ATTR_ALLOC, "ALLOC" }
/*
* The maximum size (into the kernel or returned from the kernel) of an
* attribute value or the buffer used for an attr_list() call. Larger
* sizes will result in an ERANGE return code.
*/
#define ATTR_MAX_VALUELEN (64*1024) /* max length of a value */
/*
* Define how lists of attribute names are returned to the user from
* the attr_list() call. A large, 32bit aligned, buffer is passed in
* along with its size. We put an array of offsets at the top that each
* reference an attrlist_ent_t and pack the attrlist_ent_t's at the bottom.
*/
typedef struct attrlist {
__s32 al_count; /* number of entries in attrlist */
__s32 al_more; /* T/F: more attrs (do call again) */
__s32 al_offset[1]; /* byte offsets of attrs [var-sized] */
} attrlist_t;
/*
* Show the interesting info about one attribute. This is what the
* al_offset[i] entry points to.
*/
typedef struct attrlist_ent { /* data from attr_list() */
__u32 a_valuelen; /* number bytes in value of attr */
char a_name[1]; /* attr name (NULL terminated) */
} attrlist_ent_t;
/*
* Given a pointer to the (char*) buffer containing the attr_list() result,
* and an index, return a pointer to the indicated attribute in the buffer.
*/
#define ATTR_ENTRY(buffer, index) \
((attrlist_ent_t *) \
&((char *)buffer)[ ((attrlist_t *)(buffer))->al_offset[index] ])
/*
* Kernel-internal version of the attrlist cursor.
*/
typedef struct attrlist_cursor_kern {
__u32 hashval; /* hash value of next entry to add */
__u32 blkno; /* block containing entry (suggestion) */
__u32 offset; /* offset in list of equal-hashvals */
__u16 pad1; /* padding to match user-level */
__u8 pad2; /* padding to match user-level */
__u8 initted; /* T/F: cursor has been initialized */
} attrlist_cursor_kern_t;
/*========================================================================
* Structure used to pass context around among the routines.
*========================================================================*/
/* void; state communicated via *context */
typedef void (*put_listent_func_t)(struct xfs_attr_list_context *, int,
unsigned char *, int, int);
typedef struct xfs_attr_list_context {
struct xfs_trans *tp;
struct xfs_inode *dp; /* inode */
struct attrlist_cursor_kern *cursor; /* position in list */
char *alist; /* output buffer */
/*
* Abort attribute list iteration if non-zero. Can be used to pass
* error values to the xfs_attr_list caller.
*/
int seen_enough;
ssize_t count; /* num used entries */
int dupcnt; /* count dup hashvals seen */
int bufsize; /* total buffer size */
int firstu; /* first used byte in buffer */
int flags; /* from VOP call */
int resynch; /* T/F: resynch with cursor */
put_listent_func_t put_listent; /* list output fmt function */
int index; /* index into output buffer */
} xfs_attr_list_context_t;
/*========================================================================
* Function prototypes for the kernel.
*========================================================================*/
/*
* Overall external interface routines.
*/
int xfs_attr_inactive(struct xfs_inode *dp);
int xfs_attr_list_int_ilocked(struct xfs_attr_list_context *);
int xfs_attr_list_int(struct xfs_attr_list_context *);
int xfs_inode_hasattr(struct xfs_inode *ip);
int xfs_attr_get_ilocked(struct xfs_inode *ip, struct xfs_da_args *args);
int xfs_attr_get(struct xfs_inode *ip, const unsigned char *name,
size_t namelen, unsigned char **value, int *valuelenp,
int flags);
int xfs_attr_set(struct xfs_inode *dp, const unsigned char *name,
size_t namelen, unsigned char *value, int valuelen, int flags);
int xfs_attr_set_args(struct xfs_da_args *args);
int xfs_attr_remove(struct xfs_inode *dp, const unsigned char *name,
size_t namelen, int flags);
int xfs_attr_remove_args(struct xfs_da_args *args);
int xfs_attr_list(struct xfs_inode *dp, char *buffer, int bufsize,
int flags, struct attrlist_cursor_kern *cursor);
bool xfs_attr_namecheck(const void *name, size_t length);
#endif /* __XFS_ATTR_H__ */
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