1/* SPDX-License-Identifier: GPL-2.0-or-later */
2/*
3 * Copyright (C) International Business Machines Corp., 2000-2002
4 */
5#ifndef _H_JFS_DMAP
6#define _H_JFS_DMAP
7
8#include "jfs_txnmgr.h"
9
10#define BMAPVERSION 1 /* version number */
11#define TREESIZE (256+64+16+4+1) /* size of a dmap tree */
12#define LEAFIND (64+16+4+1) /* index of 1st leaf of a dmap tree */
13#define LPERDMAP 256 /* num leaves per dmap tree */
14#define L2LPERDMAP 8 /* l2 number of leaves per dmap tree */
15#define DBWORD 32 /* # of blks covered by a map word */
16#define L2DBWORD 5 /* l2 # of blks covered by a mword */
17#define BUDMIN L2DBWORD /* max free string in a map word */
18#define BPERDMAP (LPERDMAP * DBWORD) /* num of blks per dmap */
19#define L2BPERDMAP 13 /* l2 num of blks per dmap */
20#define CTLTREESIZE (1024+256+64+16+4+1) /* size of a dmapctl tree */
21#define CTLLEAFIND (256+64+16+4+1) /* idx of 1st leaf of a dmapctl tree */
22#define LPERCTL 1024 /* num of leaves per dmapctl tree */
23#define L2LPERCTL 10 /* l2 num of leaves per dmapctl tree */
24#define ROOT 0 /* index of the root of a tree */
25#define NOFREE ((s8) -1) /* no blocks free */
26#define MAXAG 128 /* max number of allocation groups */
27#define L2MAXAG 7 /* l2 max num of AG */
28#define L2MINAGSZ 25 /* l2 of minimum AG size in bytes */
29#define BMAPBLKNO 0 /* lblkno of bmap within the map */
30
31/*
32 * maximum l2 number of disk blocks at the various dmapctl levels.
33 */
34#define L2MAXL0SIZE (L2BPERDMAP + 1 * L2LPERCTL)
35#define L2MAXL1SIZE (L2BPERDMAP + 2 * L2LPERCTL)
36#define L2MAXL2SIZE (L2BPERDMAP + 3 * L2LPERCTL)
37
38/*
39 * maximum number of disk blocks at the various dmapctl levels.
40 */
41#define MAXL0SIZE ((s64)1 << L2MAXL0SIZE)
42#define MAXL1SIZE ((s64)1 << L2MAXL1SIZE)
43#define MAXL2SIZE ((s64)1 << L2MAXL2SIZE)
44
45#define MAXMAPSIZE MAXL2SIZE /* maximum aggregate map size */
46
47/*
48 * determine the maximum free string for four (lower level) nodes
49 * of the tree.
50 */
51static inline signed char TREEMAX(signed char *cp)
52{
53 signed char tmp1, tmp2;
54
55 tmp1 = max(*(cp+2), *(cp+3));
56 tmp2 = max(*(cp), *(cp+1));
57
58 return max(tmp1, tmp2);
59}
60
61/*
62 * convert disk block number to the logical block number of the dmap
63 * describing the disk block. s is the log2(number of logical blocks per page)
64 *
65 * The calculation figures out how many logical pages are in front of the dmap.
66 * - the number of dmaps preceding it
67 * - the number of L0 pages preceding its L0 page
68 * - the number of L1 pages preceding its L1 page
69 * - 3 is added to account for the L2, L1, and L0 page for this dmap
70 * - 1 is added to account for the control page of the map.
71 */
72#define BLKTODMAP(b,s) \
73 ((((b) >> 13) + ((b) >> 23) + ((b) >> 33) + 3 + 1) << (s))
74
75/*
76 * convert disk block number to the logical block number of the LEVEL 0
77 * dmapctl describing the disk block. s is the log2(number of logical blocks
78 * per page)
79 *
80 * The calculation figures out how many logical pages are in front of the L0.
81 * - the number of dmap pages preceding it
82 * - the number of L0 pages preceding it
83 * - the number of L1 pages preceding its L1 page
84 * - 2 is added to account for the L2, and L1 page for this L0
85 * - 1 is added to account for the control page of the map.
86 */
87#define BLKTOL0(b,s) \
88 (((((b) >> 23) << 10) + ((b) >> 23) + ((b) >> 33) + 2 + 1) << (s))
89
90/*
91 * convert disk block number to the logical block number of the LEVEL 1
92 * dmapctl describing the disk block. s is the log2(number of logical blocks
93 * per page)
94 *
95 * The calculation figures out how many logical pages are in front of the L1.
96 * - the number of dmap pages preceding it
97 * - the number of L0 pages preceding it
98 * - the number of L1 pages preceding it
99 * - 1 is added to account for the L2 page
100 * - 1 is added to account for the control page of the map.
101 */
102#define BLKTOL1(b,s) \
103 (((((b) >> 33) << 20) + (((b) >> 33) << 10) + ((b) >> 33) + 1 + 1) << (s))
104
105/*
106 * convert disk block number to the logical block number of the dmapctl
107 * at the specified level which describes the disk block.
108 */
109#define BLKTOCTL(b,s,l) \
110 (((l) == 2) ? 1 : ((l) == 1) ? BLKTOL1((b),(s)) : BLKTOL0((b),(s)))
111
112/*
113 * convert aggregate map size to the zero origin dmapctl level of the
114 * top dmapctl.
115 */
116#define BMAPSZTOLEV(size) \
117 (((size) <= MAXL0SIZE) ? 0 : ((size) <= MAXL1SIZE) ? 1 : 2)
118
119/* convert disk block number to allocation group number.
120 */
121#define BLKTOAG(b,sbi) ((b) >> ((sbi)->bmap->db_agl2size))
122
123/* convert allocation group number to starting disk block
124 * number.
125 */
126#define AGTOBLK(a,ip) \
127 ((s64)(a) << (JFS_SBI((ip)->i_sb)->bmap->db_agl2size))
128
129/*
130 * dmap summary tree
131 *
132 * dmaptree must be consistent with dmapctl.
133 */
134struct dmaptree {
135 __le32 nleafs; /* 4: number of tree leafs */
136 __le32 l2nleafs; /* 4: l2 number of tree leafs */
137 __le32 leafidx; /* 4: index of first tree leaf */
138 __le32 height; /* 4: height of the tree */
139 s8 budmin; /* 1: min l2 tree leaf value to combine */
140 s8 stree[TREESIZE]; /* TREESIZE: tree */
141 u8 pad[2]; /* 2: pad to word boundary */
142}; /* - 360 - */
143
144/*
145 * dmap page per 8K blocks bitmap
146 */
147struct dmap {
148 __le32 nblocks; /* 4: num blks covered by this dmap */
149 __le32 nfree; /* 4: num of free blks in this dmap */
150 __le64 start; /* 8: starting blkno for this dmap */
151 struct dmaptree tree; /* 360: dmap tree */
152 u8 pad[1672]; /* 1672: pad to 2048 bytes */
153 __le32 wmap[LPERDMAP]; /* 1024: bits of the working map */
154 __le32 pmap[LPERDMAP]; /* 1024: bits of the persistent map */
155}; /* - 4096 - */
156
157/*
158 * disk map control page per level.
159 *
160 * dmapctl must be consistent with dmaptree.
161 */
162struct dmapctl {
163 __le32 nleafs; /* 4: number of tree leafs */
164 __le32 l2nleafs; /* 4: l2 number of tree leafs */
165 __le32 leafidx; /* 4: index of the first tree leaf */
166 __le32 height; /* 4: height of tree */
167 s8 budmin; /* 1: minimum l2 tree leaf value */
168 s8 stree[CTLTREESIZE]; /* CTLTREESIZE: dmapctl tree */
169 u8 pad[2714]; /* 2714: pad to 4096 */
170}; /* - 4096 - */
171
172/*
173 * common definition for dmaptree within dmap and dmapctl
174 */
175typedef union dmtree {
176 struct dmaptree t1;
177 struct dmapctl t2;
178} dmtree_t;
179
180/* macros for accessing fields within dmtree */
181#define dmt_nleafs t1.nleafs
182#define dmt_l2nleafs t1.l2nleafs
183#define dmt_leafidx t1.leafidx
184#define dmt_height t1.height
185#define dmt_budmin t1.budmin
186#define dmt_stree t2.stree
187
188/*
189 * on-disk aggregate disk allocation map descriptor.
190 */
191struct dbmap_disk {
192 __le64 dn_mapsize; /* 8: number of blocks in aggregate */
193 __le64 dn_nfree; /* 8: num free blks in aggregate map */
194 __le32 dn_l2nbperpage; /* 4: number of blks per page */
195 __le32 dn_numag; /* 4: total number of ags */
196 __le32 dn_maxlevel; /* 4: number of active ags */
197 __le32 dn_maxag; /* 4: max active alloc group number */
198 __le32 dn_agpref; /* 4: preferred alloc group (hint) */
199 __le32 dn_aglevel; /* 4: dmapctl level holding the AG */
200 __le32 dn_agheight; /* 4: height in dmapctl of the AG */
201 __le32 dn_agwidth; /* 4: width in dmapctl of the AG */
202 __le32 dn_agstart; /* 4: start tree index at AG height */
203 __le32 dn_agl2size; /* 4: l2 num of blks per alloc group */
204 __le64 dn_agfree[MAXAG];/* 8*MAXAG: per AG free count */
205 __le64 dn_agsize; /* 8: num of blks per alloc group */
206 s8 dn_maxfreebud; /* 1: max free buddy system */
207 u8 pad[3007]; /* 3007: pad to 4096 */
208}; /* - 4096 - */
209
210struct dbmap {
211 s64 dn_mapsize; /* number of blocks in aggregate */
212 s64 dn_nfree; /* num free blks in aggregate map */
213 int dn_l2nbperpage; /* number of blks per page */
214 int dn_numag; /* total number of ags */
215 int dn_maxlevel; /* number of active ags */
216 int dn_maxag; /* max active alloc group number */
217 int dn_agpref; /* preferred alloc group (hint) */
218 int dn_aglevel; /* dmapctl level holding the AG */
219 int dn_agheight; /* height in dmapctl of the AG */
220 int dn_agwidth; /* width in dmapctl of the AG */
221 int dn_agstart; /* start tree index at AG height */
222 int dn_agl2size; /* l2 num of blks per alloc group */
223 s64 dn_agfree[MAXAG]; /* per AG free count */
224 s64 dn_agsize; /* num of blks per alloc group */
225 signed char dn_maxfreebud; /* max free buddy system */
226}; /* - 4096 - */
227/*
228 * in-memory aggregate disk allocation map descriptor.
229 */
230struct bmap {
231 struct dbmap db_bmap; /* on-disk aggregate map descriptor */
232 struct inode *db_ipbmap; /* ptr to aggregate map incore inode */
233 struct mutex db_bmaplock; /* aggregate map lock */
234 atomic_t db_active[MAXAG]; /* count of active, open files in AG */
235 u32 *db_DBmap;
236};
237
238/* macros for accessing fields within in-memory aggregate map descriptor */
239#define db_mapsize db_bmap.dn_mapsize
240#define db_nfree db_bmap.dn_nfree
241#define db_agfree db_bmap.dn_agfree
242#define db_agsize db_bmap.dn_agsize
243#define db_agl2size db_bmap.dn_agl2size
244#define db_agwidth db_bmap.dn_agwidth
245#define db_agheight db_bmap.dn_agheight
246#define db_agstart db_bmap.dn_agstart
247#define db_numag db_bmap.dn_numag
248#define db_maxlevel db_bmap.dn_maxlevel
249#define db_aglevel db_bmap.dn_aglevel
250#define db_agpref db_bmap.dn_agpref
251#define db_maxag db_bmap.dn_maxag
252#define db_maxfreebud db_bmap.dn_maxfreebud
253#define db_l2nbperpage db_bmap.dn_l2nbperpage
254
255/*
256 * macros for various conversions needed by the allocators.
257 * blkstol2(), cntlz(), and cnttz() are operating system dependent functions.
258 */
259/* convert number of blocks to log2 number of blocks, rounding up to
260 * the next log2 value if blocks is not a l2 multiple.
261 */
262#define BLKSTOL2(d) (blkstol2(d))
263
264/* convert number of leafs to log2 leaf value */
265#define NLSTOL2BSZ(n) (31 - cntlz((n)) + BUDMIN)
266
267/* convert leaf index to log2 leaf value */
268#define LITOL2BSZ(n,m,b) ((((n) == 0) ? (m) : cnttz((n))) + (b))
269
270/* convert a block number to a dmap control leaf index */
271#define BLKTOCTLLEAF(b,m) \
272 (((b) & (((s64)1 << ((m) + L2LPERCTL)) - 1)) >> (m))
273
274/* convert log2 leaf value to buddy size */
275#define BUDSIZE(s,m) (1 << ((s) - (m)))
276
277/*
278 * external references.
279 */
280extern int dbMount(struct inode *ipbmap);
281
282extern int dbUnmount(struct inode *ipbmap, int mounterror);
283
284extern int dbFree(struct inode *ipbmap, s64 blkno, s64 nblocks);
285
286extern int dbUpdatePMap(struct inode *ipbmap,
287 int free, s64 blkno, s64 nblocks, struct tblock * tblk);
288
289extern int dbNextAG(struct inode *ipbmap);
290
291extern int dbAlloc(struct inode *ipbmap, s64 hint, s64 nblocks, s64 * results);
292
293extern int dbReAlloc(struct inode *ipbmap,
294 s64 blkno, s64 nblocks, s64 addnblocks, s64 * results);
295
296extern int dbSync(struct inode *ipbmap);
297extern int dbAllocBottomUp(struct inode *ip, s64 blkno, s64 nblocks);
298extern int dbExtendFS(struct inode *ipbmap, s64 blkno, s64 nblocks);
299extern void dbFinalizeBmap(struct inode *ipbmap);
300extern s64 dbMapFileSizeToMapSize(struct inode *ipbmap);
301extern s64 dbDiscardAG(struct inode *ip, int agno, s64 minlen);
302
303#endif /* _H_JFS_DMAP */
304

source code of linux/fs/jfs/jfs_dmap.h