linux/fs/reiserfs/xattr_user.c

#include <linux/reiserfs_fs.h>
#include <linux/errno.h>
#include <linux/fs.h>
#include <linux/pagemap.h>
#include <linux/xattr.h>
#include <linux/reiserfs_xattr.h>
#include <asm/uaccess.h>

#ifdef CONFIG_REISERFS_FS_POSIX_ACL
# include <linux/reiserfs_acl.h>
#endif

#define XATTR_USER_PREFIX "user."

static int
user_get(struct inode *inode, const char *name, void *buffer, size_t size)
{

	int error;

	if (strlen(name) < sizeof(XATTR_USER_PREFIX))
		return -EINVAL;

	if (!reiserfs_xattrs_user(inode->i_sb))
		return -EOPNOTSUPP;

	error = reiserfs_permission_locked(inode, MAY_READ, NULL);
	if (error)
		return error;

	return reiserfs_xattr_get(inode, name, buffer, size);
}

static int
user_set(struct inode *inode, const char *name, const void *buffer,
	 size_t size, int flags)
{

	int error;

	if (strlen(name) < sizeof(XATTR_USER_PREFIX))
		return -EINVAL;

	if (!reiserfs_xattrs_user(inode->i_sb))
		return -EOPNOTSUPP;

	if (!S_ISREG(inode->i_mode) &&
	    (!S_ISDIR(inode->i_mode) || inode->i_mode & S_ISVTX))
		return -EPERM;

	error = reiserfs_permission_locked(inode, MAY_WRITE, NULL);
	if (error)
		return error;

	return reiserfs_xattr_set(inode, name, buffer, size, flags);
}

static int user_del(struct inode *inode, const char *name)
{
	int error;

	if (strlen(name) < sizeof(XATTR_USER_PREFIX))
		return -EINVAL;

	if (!reiserfs_xattrs_user(inode->i_sb))
		return -EOPNOTSUPP;

	if (!S_ISREG(inode->i_mode) &&
	    (!S_ISDIR(inode->i_mode) || inode->i_mode & S_ISVTX))
		return -EPERM;

	error = reiserfs_permission_locked(inode, MAY_WRITE, NULL);
	if (error)
		return error;

	return 0;
}

static int
user_list(struct inode *inode, const char *name, int namelen, char *out)
{
	int len = namelen;
	if (!reiserfs_xattrs_user(inode->i_sb))
		return 0;

	if (out)
		memcpy(out, name, len);

	return len;
}

struct reiserfs_xattr_handler user_handler = {
	.prefix = XATTR_USER_PREFIX,
	.get = user_get,
	.set = user_set,
	.del = user_del,
	.list = user_list,
};