From 035e00acb5c719bd003639b90716a7e94e023b73 Mon Sep 17 00:00:00 2001 From: "Darrick J. Wong" Date: Wed, 3 Aug 2016 11:36:07 +1000 Subject: xfs: define the on-disk rmap btree format Originally-From: Dave Chinner Now we have all the surrounding call infrastructure in place, we can start filling out the rmap btree implementation. Start with the on-disk btree format; add everything needed to read, write and manipulate rmap btree blocks. This prepares the way for adding the btree operations implementation. [darrick: record owner and offset info in rmap btree] [darrick: fork, bmbt and unwritten state in rmap btree] [darrick: flags are a separate field in xfs_rmap_irec] [darrick: calculate maxlevels separately] [darrick: move the 'unwritten' bit into unused parts of rm_offset] Signed-off-by: Dave Chinner Signed-off-by: Darrick J. Wong Reviewed-by: Dave Chinner Reviewed-by: Brian Foster Signed-off-by: Dave Chinner --- fs/xfs/libxfs/xfs_rmap_btree.h | 55 ++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 55 insertions(+) create mode 100644 fs/xfs/libxfs/xfs_rmap_btree.h (limited to 'fs/xfs/libxfs/xfs_rmap_btree.h') diff --git a/fs/xfs/libxfs/xfs_rmap_btree.h b/fs/xfs/libxfs/xfs_rmap_btree.h new file mode 100644 index 000000000000..a3a6b7d476c7 --- /dev/null +++ b/fs/xfs/libxfs/xfs_rmap_btree.h @@ -0,0 +1,55 @@ +/* + * Copyright (c) 2014 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 + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * 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_RMAP_BTREE_H__ +#define __XFS_RMAP_BTREE_H__ + +struct xfs_buf; +struct xfs_btree_cur; +struct xfs_mount; + +/* rmaps only exist on crc enabled filesystems */ +#define XFS_RMAP_BLOCK_LEN XFS_BTREE_SBLOCK_CRC_LEN + +/* + * Record, key, and pointer address macros for btree blocks. + * + * (note that some of these may appear unused, but they are used in userspace) + */ +#define XFS_RMAP_REC_ADDR(block, index) \ + ((struct xfs_rmap_rec *) \ + ((char *)(block) + XFS_RMAP_BLOCK_LEN + \ + (((index) - 1) * sizeof(struct xfs_rmap_rec)))) + +#define XFS_RMAP_KEY_ADDR(block, index) \ + ((struct xfs_rmap_key *) \ + ((char *)(block) + XFS_RMAP_BLOCK_LEN + \ + ((index) - 1) * sizeof(struct xfs_rmap_key))) + +#define XFS_RMAP_PTR_ADDR(block, index, maxrecs) \ + ((xfs_rmap_ptr_t *) \ + ((char *)(block) + XFS_RMAP_BLOCK_LEN + \ + (maxrecs) * sizeof(struct xfs_rmap_key) + \ + ((index) - 1) * sizeof(xfs_rmap_ptr_t))) + +struct xfs_btree_cur *xfs_rmapbt_init_cursor(struct xfs_mount *mp, + struct xfs_trans *tp, struct xfs_buf *bp, + xfs_agnumber_t agno); +int xfs_rmapbt_maxrecs(struct xfs_mount *mp, int blocklen, int leaf); +extern void xfs_rmapbt_compute_maxlevels(struct xfs_mount *mp); + +#endif /* __XFS_RMAP_BTREE_H__ */ -- cgit v1.2.3