blob: 92a8fd7977cc2b48649ed3e5c22344fe83fcd8c1 [file] [log] [blame]
* Copyright (c) 2013 Red Hat, Inc.
* All Rights Reserved.
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License as
* published by the Free Software Foundation.
* This program is distributed in the hope that it would be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* GNU General Public License for more details.
* You should have received a copy of the GNU General Public License
* along with this program; if not, write the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
#ifndef __XFS_ATTR_REMOTE_H__
#define __XFS_ATTR_REMOTE_H__
#define XFS_ATTR3_RMT_MAGIC 0x5841524d /* XARM */
* There is one of these headers per filesystem block in a remote attribute.
* This is done to ensure there is a 1:1 mapping between the attribute value
* length and the number of blocks needed to store the attribute. This makes the
* verification of a buffer a little more complex, but greatly simplifies the
* allocation, reading and writing of these attributes as we don't have to guess
* the number of blocks needed to store the attribute data.
struct xfs_attr3_rmt_hdr {
__be32 rm_magic;
__be32 rm_offset;
__be32 rm_bytes;
__be32 rm_crc;
uuid_t rm_uuid;
__be64 rm_owner;
__be64 rm_blkno;
__be64 rm_lsn;
#define XFS_ATTR3_RMT_CRC_OFF offsetof(struct xfs_attr3_rmt_hdr, rm_crc)
#define XFS_ATTR3_RMT_BUF_SPACE(mp, bufsize) \
((bufsize) - (xfs_sb_version_hascrc(&(mp)->m_sb) ? \
sizeof(struct xfs_attr3_rmt_hdr) : 0))
extern const struct xfs_buf_ops xfs_attr3_rmt_buf_ops;
int xfs_attr3_rmt_blocks(struct xfs_mount *mp, int attrlen);
int xfs_attr_rmtval_get(struct xfs_da_args *args);
int xfs_attr_rmtval_set(struct xfs_da_args *args);
int xfs_attr_rmtval_remove(struct xfs_da_args *args);
#endif /* __XFS_ATTR_REMOTE_H__ */