linux/include/linux/xattr.h
Andreas Gruenbacher 764a5c6b1f xattr handlers: Simplify list operation
Change the list operation to only return whether or not an attribute
should be listed.  Copying the attribute names into the buffer is moved
to the callers.

Since the result only depends on the dentry and not on the attribute
name, we do not pass the attribute name to list operations.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-12-13 19:46:12 -05:00

111 lines
3.3 KiB
C

/*
File: linux/xattr.h
Extended attributes handling.
Copyright (C) 2001 by Andreas Gruenbacher <a.gruenbacher@computer.org>
Copyright (c) 2001-2002 Silicon Graphics, Inc. All Rights Reserved.
Copyright (c) 2004 Red Hat, Inc., James Morris <jmorris@redhat.com>
*/
#ifndef _LINUX_XATTR_H
#define _LINUX_XATTR_H
#include <linux/slab.h>
#include <linux/types.h>
#include <linux/spinlock.h>
#include <uapi/linux/xattr.h>
struct inode;
struct dentry;
/*
* struct xattr_handler: When @name is set, match attributes with exactly that
* name. When @prefix is set instead, match attributes with that prefix and
* with a non-empty suffix.
*/
struct xattr_handler {
const char *name;
const char *prefix;
int flags; /* fs private flags */
bool (*list)(struct dentry *dentry);
int (*get)(const struct xattr_handler *, struct dentry *dentry,
const char *name, void *buffer, size_t size);
int (*set)(const struct xattr_handler *, struct dentry *dentry,
const char *name, const void *buffer, size_t size,
int flags);
};
const char *xattr_full_name(const struct xattr_handler *, const char *);
struct xattr {
const char *name;
void *value;
size_t value_len;
};
ssize_t xattr_getsecurity(struct inode *, const char *, void *, size_t);
ssize_t vfs_getxattr(struct dentry *, const char *, void *, size_t);
ssize_t vfs_listxattr(struct dentry *d, char *list, size_t size);
int __vfs_setxattr_noperm(struct dentry *, const char *, const void *, size_t, int);
int vfs_setxattr(struct dentry *, const char *, const void *, size_t, int);
int vfs_removexattr(struct dentry *, const char *);
ssize_t generic_getxattr(struct dentry *dentry, const char *name, void *buffer, size_t size);
ssize_t generic_listxattr(struct dentry *dentry, char *buffer, size_t buffer_size);
int generic_setxattr(struct dentry *dentry, const char *name, const void *value, size_t size, int flags);
int generic_removexattr(struct dentry *dentry, const char *name);
ssize_t vfs_getxattr_alloc(struct dentry *dentry, const char *name,
char **xattr_value, size_t size, gfp_t flags);
static inline const char *xattr_prefix(const struct xattr_handler *handler)
{
return handler->prefix ?: handler->name;
}
struct simple_xattrs {
struct list_head head;
spinlock_t lock;
};
struct simple_xattr {
struct list_head list;
char *name;
size_t size;
char value[0];
};
/*
* initialize the simple_xattrs structure
*/
static inline void simple_xattrs_init(struct simple_xattrs *xattrs)
{
INIT_LIST_HEAD(&xattrs->head);
spin_lock_init(&xattrs->lock);
}
/*
* free all the xattrs
*/
static inline void simple_xattrs_free(struct simple_xattrs *xattrs)
{
struct simple_xattr *xattr, *node;
list_for_each_entry_safe(xattr, node, &xattrs->head, list) {
kfree(xattr->name);
kfree(xattr);
}
}
struct simple_xattr *simple_xattr_alloc(const void *value, size_t size);
int simple_xattr_get(struct simple_xattrs *xattrs, const char *name,
void *buffer, size_t size);
int simple_xattr_set(struct simple_xattrs *xattrs, const char *name,
const void *value, size_t size, int flags);
ssize_t simple_xattr_list(struct inode *inode, struct simple_xattrs *xattrs, char *buffer,
size_t size);
void simple_xattr_list_add(struct simple_xattrs *xattrs,
struct simple_xattr *new_xattr);
#endif /* _LINUX_XATTR_H */