1 /* SPDX-License-Identifier: GPL-2.0+ */
2 /*
3  *  GRUB  --  GRand Unified Bootloader
4  *  Copyright (C) 1999,2000,2001,2002,2003,2004  Free Software Foundation, Inc.
5  */
6 /*
7  * Copyright 2010 Sun Microsystems, Inc.  All rights reserved.
8  * Use is subject to license terms.
9  */
10 
11 #ifndef	_SYS_DNODE_H
12 #define	_SYS_DNODE_H
13 
14 #include <zfs/spa.h>
15 
16 /*
17  * Fixed constants.
18  */
19 #define	DNODE_SHIFT		9	/* 512 bytes */
20 #define	DN_MIN_INDBLKSHIFT	10	/* 1k */
21 #define	DN_MAX_INDBLKSHIFT	14	/* 16k */
22 #define	DNODE_BLOCK_SHIFT	14	/* 16k */
23 #define	DNODE_CORE_SIZE		64	/* 64 bytes for dnode sans blkptrs */
24 #define	DN_MAX_OBJECT_SHIFT	48	/* 256 trillion (zfs_fid_t limit) */
25 #define	DN_MAX_OFFSET_SHIFT	64	/* 2^64 bytes in a dnode */
26 
27 /*
28  * Derived constants.
29  */
30 #define	DNODE_SIZE	(1 << DNODE_SHIFT)
31 #define	DN_MAX_NBLKPTR	((DNODE_SIZE - DNODE_CORE_SIZE) >> SPA_BLKPTRSHIFT)
32 #define	DN_MAX_BONUSLEN	(DNODE_SIZE - DNODE_CORE_SIZE - (1 << SPA_BLKPTRSHIFT))
33 #define	DN_MAX_OBJECT	(1ULL << DN_MAX_OBJECT_SHIFT)
34 
35 #define	DNODES_PER_BLOCK_SHIFT	(DNODE_BLOCK_SHIFT - DNODE_SHIFT)
36 #define	DNODES_PER_BLOCK	(1ULL << DNODES_PER_BLOCK_SHIFT)
37 #define	DNODES_PER_LEVEL_SHIFT	(DN_MAX_INDBLKSHIFT - SPA_BLKPTRSHIFT)
38 
39 #define	DNODE_FLAG_SPILL_BLKPTR (1<<2)
40 
41 #define	DN_BONUS(dnp)	((void *)((dnp)->dn_bonus + \
42 	(((dnp)->dn_nblkptr - 1) * sizeof(blkptr_t))))
43 
44 typedef struct dnode_phys {
45 	uint8_t dn_type;		/* dmu_object_type_t */
46 	uint8_t dn_indblkshift;		/* ln2(indirect block size) */
47 	uint8_t dn_nlevels;		/* 1=dn_blkptr->data blocks */
48 	uint8_t dn_nblkptr;		/* length of dn_blkptr */
49 	uint8_t dn_bonustype;		/* type of data in bonus buffer */
50 	uint8_t	dn_checksum;		/* ZIO_CHECKSUM type */
51 	uint8_t	dn_compress;		/* ZIO_COMPRESS type */
52 	uint8_t dn_flags;		/* DNODE_FLAG_* */
53 	uint16_t dn_datablkszsec;	/* data block size in 512b sectors */
54 	uint16_t dn_bonuslen;		/* length of dn_bonus */
55 	uint8_t dn_pad2[4];
56 
57 	/* accounting is protected by dn_dirty_mtx */
58 	uint64_t dn_maxblkid;		/* largest allocated block ID */
59 	uint64_t dn_used;		/* bytes (or sectors) of disk space */
60 
61 	uint64_t dn_pad3[4];
62 
63 	blkptr_t dn_blkptr[1];
64 	uint8_t dn_bonus[DN_MAX_BONUSLEN - sizeof(blkptr_t)];
65 	blkptr_t dn_spill;
66 } dnode_phys_t;
67 
68 #endif	/* _SYS_DNODE_H */
69