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1da177e4 LT |
1 | /* |
2 | * Copyright (C) International Business Machines Corp., 2000-2004 | |
3 | * | |
4 | * This program is free software; you can redistribute it and/or modify | |
5 | * it under the terms of the GNU General Public License as published by | |
6 | * the Free Software Foundation; either version 2 of the License, or | |
7 | * (at your option) any later version. | |
8 | * | |
9 | * This program is distributed in the hope that it will be useful, | |
10 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
11 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See | |
12 | * the GNU General Public License for more details. | |
13 | * | |
14 | * You should have received a copy of the GNU General Public License | |
15 | * along with this program; if not, write to the Free Software | |
16 | * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA | |
17 | */ | |
18 | ||
19 | #include <linux/fs.h> | |
20 | #include "jfs_incore.h" | |
21 | #include "jfs_superblock.h" | |
22 | #include "jfs_dmap.h" | |
23 | #include "jfs_imap.h" | |
24 | #include "jfs_lock.h" | |
25 | #include "jfs_metapage.h" | |
26 | #include "jfs_debug.h" | |
27 | ||
28 | /* | |
29 | * Debug code for double-checking block map | |
30 | */ | |
31 | /* #define _JFS_DEBUG_DMAP 1 */ | |
32 | ||
33 | #ifdef _JFS_DEBUG_DMAP | |
34 | #define DBINITMAP(size,ipbmap,results) \ | |
35 | DBinitmap(size,ipbmap,results) | |
36 | #define DBALLOC(dbmap,mapsize,blkno,nblocks) \ | |
37 | DBAlloc(dbmap,mapsize,blkno,nblocks) | |
38 | #define DBFREE(dbmap,mapsize,blkno,nblocks) \ | |
39 | DBFree(dbmap,mapsize,blkno,nblocks) | |
40 | #define DBALLOCCK(dbmap,mapsize,blkno,nblocks) \ | |
41 | DBAllocCK(dbmap,mapsize,blkno,nblocks) | |
42 | #define DBFREECK(dbmap,mapsize,blkno,nblocks) \ | |
43 | DBFreeCK(dbmap,mapsize,blkno,nblocks) | |
44 | ||
45 | static void DBinitmap(s64, struct inode *, u32 **); | |
46 | static void DBAlloc(uint *, s64, s64, s64); | |
47 | static void DBFree(uint *, s64, s64, s64); | |
48 | static void DBAllocCK(uint *, s64, s64, s64); | |
49 | static void DBFreeCK(uint *, s64, s64, s64); | |
50 | #else | |
51 | #define DBINITMAP(size,ipbmap,results) | |
52 | #define DBALLOC(dbmap, mapsize, blkno, nblocks) | |
53 | #define DBFREE(dbmap, mapsize, blkno, nblocks) | |
54 | #define DBALLOCCK(dbmap, mapsize, blkno, nblocks) | |
55 | #define DBFREECK(dbmap, mapsize, blkno, nblocks) | |
56 | #endif /* _JFS_DEBUG_DMAP */ | |
57 | ||
58 | /* | |
59 | * SERIALIZATION of the Block Allocation Map. | |
60 | * | |
61 | * the working state of the block allocation map is accessed in | |
62 | * two directions: | |
63 | * | |
64 | * 1) allocation and free requests that start at the dmap | |
65 | * level and move up through the dmap control pages (i.e. | |
66 | * the vast majority of requests). | |
67 | * | |
68 | * 2) allocation requests that start at dmap control page | |
69 | * level and work down towards the dmaps. | |
70 | * | |
71 | * the serialization scheme used here is as follows. | |
72 | * | |
73 | * requests which start at the bottom are serialized against each | |
74 | * other through buffers and each requests holds onto its buffers | |
75 | * as it works it way up from a single dmap to the required level | |
76 | * of dmap control page. | |
77 | * requests that start at the top are serialized against each other | |
78 | * and request that start from the bottom by the multiple read/single | |
79 | * write inode lock of the bmap inode. requests starting at the top | |
80 | * take this lock in write mode while request starting at the bottom | |
81 | * take the lock in read mode. a single top-down request may proceed | |
82 | * exclusively while multiple bottoms-up requests may proceed | |
83 | * simultaneously (under the protection of busy buffers). | |
84 | * | |
85 | * in addition to information found in dmaps and dmap control pages, | |
86 | * the working state of the block allocation map also includes read/ | |
87 | * write information maintained in the bmap descriptor (i.e. total | |
88 | * free block count, allocation group level free block counts). | |
89 | * a single exclusive lock (BMAP_LOCK) is used to guard this information | |
90 | * in the face of multiple-bottoms up requests. | |
91 | * (lock ordering: IREAD_LOCK, BMAP_LOCK); | |
92 | * | |
93 | * accesses to the persistent state of the block allocation map (limited | |
94 | * to the persistent bitmaps in dmaps) is guarded by (busy) buffers. | |
95 | */ | |
96 | ||
97 | #define BMAP_LOCK_INIT(bmp) init_MUTEX(&bmp->db_bmaplock) | |
98 | #define BMAP_LOCK(bmp) down(&bmp->db_bmaplock) | |
99 | #define BMAP_UNLOCK(bmp) up(&bmp->db_bmaplock) | |
100 | ||
101 | /* | |
102 | * forward references | |
103 | */ | |
104 | static void dbAllocBits(struct bmap * bmp, struct dmap * dp, s64 blkno, | |
105 | int nblocks); | |
106 | static void dbSplit(dmtree_t * tp, int leafno, int splitsz, int newval); | |
107 | static void dbBackSplit(dmtree_t * tp, int leafno); | |
108 | static void dbJoin(dmtree_t * tp, int leafno, int newval); | |
109 | static void dbAdjTree(dmtree_t * tp, int leafno, int newval); | |
110 | static int dbAdjCtl(struct bmap * bmp, s64 blkno, int newval, int alloc, | |
111 | int level); | |
112 | static int dbAllocAny(struct bmap * bmp, s64 nblocks, int l2nb, s64 * results); | |
113 | static int dbAllocNext(struct bmap * bmp, struct dmap * dp, s64 blkno, | |
114 | int nblocks); | |
115 | static int dbAllocNear(struct bmap * bmp, struct dmap * dp, s64 blkno, | |
116 | int nblocks, | |
117 | int l2nb, s64 * results); | |
118 | static int dbAllocDmap(struct bmap * bmp, struct dmap * dp, s64 blkno, | |
119 | int nblocks); | |
120 | static int dbAllocDmapLev(struct bmap * bmp, struct dmap * dp, int nblocks, | |
121 | int l2nb, | |
122 | s64 * results); | |
123 | static int dbAllocAG(struct bmap * bmp, int agno, s64 nblocks, int l2nb, | |
124 | s64 * results); | |
125 | static int dbAllocCtl(struct bmap * bmp, s64 nblocks, int l2nb, s64 blkno, | |
126 | s64 * results); | |
127 | static int dbExtend(struct inode *ip, s64 blkno, s64 nblocks, s64 addnblocks); | |
128 | static int dbFindBits(u32 word, int l2nb); | |
129 | static int dbFindCtl(struct bmap * bmp, int l2nb, int level, s64 * blkno); | |
130 | static int dbFindLeaf(dmtree_t * tp, int l2nb, int *leafidx); | |
131 | static void dbFreeBits(struct bmap * bmp, struct dmap * dp, s64 blkno, | |
132 | int nblocks); | |
133 | static int dbFreeDmap(struct bmap * bmp, struct dmap * dp, s64 blkno, | |
134 | int nblocks); | |
135 | static int dbMaxBud(u8 * cp); | |
136 | s64 dbMapFileSizeToMapSize(struct inode *ipbmap); | |
137 | static int blkstol2(s64 nb); | |
138 | ||
139 | static int cntlz(u32 value); | |
140 | static int cnttz(u32 word); | |
141 | ||
142 | static int dbAllocDmapBU(struct bmap * bmp, struct dmap * dp, s64 blkno, | |
143 | int nblocks); | |
144 | static int dbInitDmap(struct dmap * dp, s64 blkno, int nblocks); | |
145 | static int dbInitDmapTree(struct dmap * dp); | |
146 | static int dbInitTree(struct dmaptree * dtp); | |
147 | static int dbInitDmapCtl(struct dmapctl * dcp, int level, int i); | |
148 | static int dbGetL2AGSize(s64 nblocks); | |
149 | ||
150 | /* | |
151 | * buddy table | |
152 | * | |
153 | * table used for determining buddy sizes within characters of | |
154 | * dmap bitmap words. the characters themselves serve as indexes | |
155 | * into the table, with the table elements yielding the maximum | |
156 | * binary buddy of free bits within the character. | |
157 | */ | |
158 | static s8 budtab[256] = { | |
159 | 3, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, | |
160 | 2, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, | |
161 | 2, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, | |
162 | 2, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, | |
163 | 2, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, | |
164 | 2, 1, 1, 1, 1, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0, | |
165 | 2, 1, 1, 1, 1, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0, | |
166 | 2, 1, 1, 1, 1, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0, | |
167 | 2, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, | |
168 | 2, 1, 1, 1, 1, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0, | |
169 | 2, 1, 1, 1, 1, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0, | |
170 | 2, 1, 1, 1, 1, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0, | |
171 | 2, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, | |
172 | 2, 1, 1, 1, 1, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0, | |
173 | 2, 1, 1, 1, 1, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0, | |
174 | 2, 1, 1, 1, 1, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, -1 | |
175 | }; | |
176 | ||
177 | ||
178 | /* | |
179 | * NAME: dbMount() | |
180 | * | |
181 | * FUNCTION: initializate the block allocation map. | |
182 | * | |
183 | * memory is allocated for the in-core bmap descriptor and | |
184 | * the in-core descriptor is initialized from disk. | |
185 | * | |
186 | * PARAMETERS: | |
187 | * ipbmap - pointer to in-core inode for the block map. | |
188 | * | |
189 | * RETURN VALUES: | |
190 | * 0 - success | |
191 | * -ENOMEM - insufficient memory | |
192 | * -EIO - i/o error | |
193 | */ | |
194 | int dbMount(struct inode *ipbmap) | |
195 | { | |
196 | struct bmap *bmp; | |
197 | struct dbmap_disk *dbmp_le; | |
198 | struct metapage *mp; | |
199 | int i; | |
200 | ||
201 | /* | |
202 | * allocate/initialize the in-memory bmap descriptor | |
203 | */ | |
204 | /* allocate memory for the in-memory bmap descriptor */ | |
205 | bmp = kmalloc(sizeof(struct bmap), GFP_KERNEL); | |
206 | if (bmp == NULL) | |
207 | return -ENOMEM; | |
208 | ||
209 | /* read the on-disk bmap descriptor. */ | |
210 | mp = read_metapage(ipbmap, | |
211 | BMAPBLKNO << JFS_SBI(ipbmap->i_sb)->l2nbperpage, | |
212 | PSIZE, 0); | |
213 | if (mp == NULL) { | |
214 | kfree(bmp); | |
215 | return -EIO; | |
216 | } | |
217 | ||
218 | /* copy the on-disk bmap descriptor to its in-memory version. */ | |
219 | dbmp_le = (struct dbmap_disk *) mp->data; | |
220 | bmp->db_mapsize = le64_to_cpu(dbmp_le->dn_mapsize); | |
221 | bmp->db_nfree = le64_to_cpu(dbmp_le->dn_nfree); | |
222 | bmp->db_l2nbperpage = le32_to_cpu(dbmp_le->dn_l2nbperpage); | |
223 | bmp->db_numag = le32_to_cpu(dbmp_le->dn_numag); | |
224 | bmp->db_maxlevel = le32_to_cpu(dbmp_le->dn_maxlevel); | |
225 | bmp->db_maxag = le32_to_cpu(dbmp_le->dn_maxag); | |
226 | bmp->db_agpref = le32_to_cpu(dbmp_le->dn_agpref); | |
227 | bmp->db_aglevel = le32_to_cpu(dbmp_le->dn_aglevel); | |
228 | bmp->db_agheigth = le32_to_cpu(dbmp_le->dn_agheigth); | |
229 | bmp->db_agwidth = le32_to_cpu(dbmp_le->dn_agwidth); | |
230 | bmp->db_agstart = le32_to_cpu(dbmp_le->dn_agstart); | |
231 | bmp->db_agl2size = le32_to_cpu(dbmp_le->dn_agl2size); | |
232 | for (i = 0; i < MAXAG; i++) | |
233 | bmp->db_agfree[i] = le64_to_cpu(dbmp_le->dn_agfree[i]); | |
234 | bmp->db_agsize = le64_to_cpu(dbmp_le->dn_agsize); | |
235 | bmp->db_maxfreebud = dbmp_le->dn_maxfreebud; | |
236 | ||
237 | /* release the buffer. */ | |
238 | release_metapage(mp); | |
239 | ||
240 | /* bind the bmap inode and the bmap descriptor to each other. */ | |
241 | bmp->db_ipbmap = ipbmap; | |
242 | JFS_SBI(ipbmap->i_sb)->bmap = bmp; | |
243 | ||
244 | memset(bmp->db_active, 0, sizeof(bmp->db_active)); | |
245 | DBINITMAP(bmp->db_mapsize, ipbmap, &bmp->db_DBmap); | |
246 | ||
247 | /* | |
248 | * allocate/initialize the bmap lock | |
249 | */ | |
250 | BMAP_LOCK_INIT(bmp); | |
251 | ||
252 | return (0); | |
253 | } | |
254 | ||
255 | ||
256 | /* | |
257 | * NAME: dbUnmount() | |
258 | * | |
259 | * FUNCTION: terminate the block allocation map in preparation for | |
260 | * file system unmount. | |
261 | * | |
262 | * the in-core bmap descriptor is written to disk and | |
263 | * the memory for this descriptor is freed. | |
264 | * | |
265 | * PARAMETERS: | |
266 | * ipbmap - pointer to in-core inode for the block map. | |
267 | * | |
268 | * RETURN VALUES: | |
269 | * 0 - success | |
270 | * -EIO - i/o error | |
271 | */ | |
272 | int dbUnmount(struct inode *ipbmap, int mounterror) | |
273 | { | |
274 | struct bmap *bmp = JFS_SBI(ipbmap->i_sb)->bmap; | |
275 | int i; | |
276 | ||
277 | if (!(mounterror || isReadOnly(ipbmap))) | |
278 | dbSync(ipbmap); | |
279 | ||
280 | /* | |
281 | * Invalidate the page cache buffers | |
282 | */ | |
283 | truncate_inode_pages(ipbmap->i_mapping, 0); | |
284 | ||
285 | /* | |
286 | * Sanity Check | |
287 | */ | |
288 | for (i = 0; i < bmp->db_numag; i++) | |
289 | if (atomic_read(&bmp->db_active[i])) | |
290 | printk(KERN_ERR "dbUnmount: db_active[%d] = %d\n", | |
291 | i, atomic_read(&bmp->db_active[i])); | |
292 | ||
293 | /* free the memory for the in-memory bmap. */ | |
294 | kfree(bmp); | |
295 | ||
296 | return (0); | |
297 | } | |
298 | ||
299 | /* | |
300 | * dbSync() | |
301 | */ | |
302 | int dbSync(struct inode *ipbmap) | |
303 | { | |
304 | struct dbmap_disk *dbmp_le; | |
305 | struct bmap *bmp = JFS_SBI(ipbmap->i_sb)->bmap; | |
306 | struct metapage *mp; | |
307 | int i; | |
308 | ||
309 | /* | |
310 | * write bmap global control page | |
311 | */ | |
312 | /* get the buffer for the on-disk bmap descriptor. */ | |
313 | mp = read_metapage(ipbmap, | |
314 | BMAPBLKNO << JFS_SBI(ipbmap->i_sb)->l2nbperpage, | |
315 | PSIZE, 0); | |
316 | if (mp == NULL) { | |
317 | jfs_err("dbSync: read_metapage failed!"); | |
318 | return -EIO; | |
319 | } | |
320 | /* copy the in-memory version of the bmap to the on-disk version */ | |
321 | dbmp_le = (struct dbmap_disk *) mp->data; | |
322 | dbmp_le->dn_mapsize = cpu_to_le64(bmp->db_mapsize); | |
323 | dbmp_le->dn_nfree = cpu_to_le64(bmp->db_nfree); | |
324 | dbmp_le->dn_l2nbperpage = cpu_to_le32(bmp->db_l2nbperpage); | |
325 | dbmp_le->dn_numag = cpu_to_le32(bmp->db_numag); | |
326 | dbmp_le->dn_maxlevel = cpu_to_le32(bmp->db_maxlevel); | |
327 | dbmp_le->dn_maxag = cpu_to_le32(bmp->db_maxag); | |
328 | dbmp_le->dn_agpref = cpu_to_le32(bmp->db_agpref); | |
329 | dbmp_le->dn_aglevel = cpu_to_le32(bmp->db_aglevel); | |
330 | dbmp_le->dn_agheigth = cpu_to_le32(bmp->db_agheigth); | |
331 | dbmp_le->dn_agwidth = cpu_to_le32(bmp->db_agwidth); | |
332 | dbmp_le->dn_agstart = cpu_to_le32(bmp->db_agstart); | |
333 | dbmp_le->dn_agl2size = cpu_to_le32(bmp->db_agl2size); | |
334 | for (i = 0; i < MAXAG; i++) | |
335 | dbmp_le->dn_agfree[i] = cpu_to_le64(bmp->db_agfree[i]); | |
336 | dbmp_le->dn_agsize = cpu_to_le64(bmp->db_agsize); | |
337 | dbmp_le->dn_maxfreebud = bmp->db_maxfreebud; | |
338 | ||
339 | /* write the buffer */ | |
340 | write_metapage(mp); | |
341 | ||
342 | /* | |
343 | * write out dirty pages of bmap | |
344 | */ | |
345 | filemap_fdatawrite(ipbmap->i_mapping); | |
346 | filemap_fdatawait(ipbmap->i_mapping); | |
347 | ||
348 | ipbmap->i_state |= I_DIRTY; | |
349 | diWriteSpecial(ipbmap, 0); | |
350 | ||
351 | return (0); | |
352 | } | |
353 | ||
354 | ||
355 | /* | |
356 | * NAME: dbFree() | |
357 | * | |
358 | * FUNCTION: free the specified block range from the working block | |
359 | * allocation map. | |
360 | * | |
361 | * the blocks will be free from the working map one dmap | |
362 | * at a time. | |
363 | * | |
364 | * PARAMETERS: | |
365 | * ip - pointer to in-core inode; | |
366 | * blkno - starting block number to be freed. | |
367 | * nblocks - number of blocks to be freed. | |
368 | * | |
369 | * RETURN VALUES: | |
370 | * 0 - success | |
371 | * -EIO - i/o error | |
372 | */ | |
373 | int dbFree(struct inode *ip, s64 blkno, s64 nblocks) | |
374 | { | |
375 | struct metapage *mp; | |
376 | struct dmap *dp; | |
377 | int nb, rc; | |
378 | s64 lblkno, rem; | |
379 | struct inode *ipbmap = JFS_SBI(ip->i_sb)->ipbmap; | |
380 | struct bmap *bmp = JFS_SBI(ip->i_sb)->bmap; | |
381 | ||
382 | IREAD_LOCK(ipbmap); | |
383 | ||
384 | /* block to be freed better be within the mapsize. */ | |
385 | if (unlikely((blkno == 0) || (blkno + nblocks > bmp->db_mapsize))) { | |
386 | IREAD_UNLOCK(ipbmap); | |
387 | printk(KERN_ERR "blkno = %Lx, nblocks = %Lx\n", | |
388 | (unsigned long long) blkno, | |
389 | (unsigned long long) nblocks); | |
390 | jfs_error(ip->i_sb, | |
391 | "dbFree: block to be freed is outside the map"); | |
392 | return -EIO; | |
393 | } | |
394 | ||
395 | /* | |
396 | * free the blocks a dmap at a time. | |
397 | */ | |
398 | mp = NULL; | |
399 | for (rem = nblocks; rem > 0; rem -= nb, blkno += nb) { | |
400 | /* release previous dmap if any */ | |
401 | if (mp) { | |
402 | write_metapage(mp); | |
403 | } | |
404 | ||
405 | /* get the buffer for the current dmap. */ | |
406 | lblkno = BLKTODMAP(blkno, bmp->db_l2nbperpage); | |
407 | mp = read_metapage(ipbmap, lblkno, PSIZE, 0); | |
408 | if (mp == NULL) { | |
409 | IREAD_UNLOCK(ipbmap); | |
410 | return -EIO; | |
411 | } | |
412 | dp = (struct dmap *) mp->data; | |
413 | ||
414 | /* determine the number of blocks to be freed from | |
415 | * this dmap. | |
416 | */ | |
417 | nb = min(rem, BPERDMAP - (blkno & (BPERDMAP - 1))); | |
418 | ||
419 | DBALLOCCK(bmp->db_DBmap, bmp->db_mapsize, blkno, nb); | |
420 | ||
421 | /* free the blocks. */ | |
422 | if ((rc = dbFreeDmap(bmp, dp, blkno, nb))) { | |
423 | release_metapage(mp); | |
424 | IREAD_UNLOCK(ipbmap); | |
425 | return (rc); | |
426 | } | |
427 | ||
428 | DBFREE(bmp->db_DBmap, bmp->db_mapsize, blkno, nb); | |
429 | } | |
430 | ||
431 | /* write the last buffer. */ | |
432 | write_metapage(mp); | |
433 | ||
434 | IREAD_UNLOCK(ipbmap); | |
435 | ||
436 | return (0); | |
437 | } | |
438 | ||
439 | ||
440 | /* | |
441 | * NAME: dbUpdatePMap() | |
442 | * | |
443 | * FUNCTION: update the allocation state (free or allocate) of the | |
444 | * specified block range in the persistent block allocation map. | |
445 | * | |
446 | * the blocks will be updated in the persistent map one | |
447 | * dmap at a time. | |
448 | * | |
449 | * PARAMETERS: | |
450 | * ipbmap - pointer to in-core inode for the block map. | |
451 | * free - TRUE if block range is to be freed from the persistent | |
452 | * map; FALSE if it is to be allocated. | |
453 | * blkno - starting block number of the range. | |
454 | * nblocks - number of contiguous blocks in the range. | |
455 | * tblk - transaction block; | |
456 | * | |
457 | * RETURN VALUES: | |
458 | * 0 - success | |
459 | * -EIO - i/o error | |
460 | */ | |
461 | int | |
462 | dbUpdatePMap(struct inode *ipbmap, | |
463 | int free, s64 blkno, s64 nblocks, struct tblock * tblk) | |
464 | { | |
465 | int nblks, dbitno, wbitno, rbits; | |
466 | int word, nbits, nwords; | |
467 | struct bmap *bmp = JFS_SBI(ipbmap->i_sb)->bmap; | |
468 | s64 lblkno, rem, lastlblkno; | |
469 | u32 mask; | |
470 | struct dmap *dp; | |
471 | struct metapage *mp; | |
472 | struct jfs_log *log; | |
473 | int lsn, difft, diffp; | |
474 | ||
475 | /* the blocks better be within the mapsize. */ | |
476 | if (blkno + nblocks > bmp->db_mapsize) { | |
477 | printk(KERN_ERR "blkno = %Lx, nblocks = %Lx\n", | |
478 | (unsigned long long) blkno, | |
479 | (unsigned long long) nblocks); | |
480 | jfs_error(ipbmap->i_sb, | |
481 | "dbUpdatePMap: blocks are outside the map"); | |
482 | return -EIO; | |
483 | } | |
484 | ||
485 | /* compute delta of transaction lsn from log syncpt */ | |
486 | lsn = tblk->lsn; | |
487 | log = (struct jfs_log *) JFS_SBI(tblk->sb)->log; | |
488 | logdiff(difft, lsn, log); | |
489 | ||
490 | /* | |
491 | * update the block state a dmap at a time. | |
492 | */ | |
493 | mp = NULL; | |
494 | lastlblkno = 0; | |
495 | for (rem = nblocks; rem > 0; rem -= nblks, blkno += nblks) { | |
496 | /* get the buffer for the current dmap. */ | |
497 | lblkno = BLKTODMAP(blkno, bmp->db_l2nbperpage); | |
498 | if (lblkno != lastlblkno) { | |
499 | if (mp) { | |
500 | write_metapage(mp); | |
501 | } | |
502 | ||
503 | mp = read_metapage(bmp->db_ipbmap, lblkno, PSIZE, | |
504 | 0); | |
505 | if (mp == NULL) | |
506 | return -EIO; | |
507 | } | |
508 | dp = (struct dmap *) mp->data; | |
509 | ||
510 | /* determine the bit number and word within the dmap of | |
511 | * the starting block. also determine how many blocks | |
512 | * are to be updated within this dmap. | |
513 | */ | |
514 | dbitno = blkno & (BPERDMAP - 1); | |
515 | word = dbitno >> L2DBWORD; | |
516 | nblks = min(rem, (s64)BPERDMAP - dbitno); | |
517 | ||
518 | /* update the bits of the dmap words. the first and last | |
519 | * words may only have a subset of their bits updated. if | |
520 | * this is the case, we'll work against that word (i.e. | |
521 | * partial first and/or last) only in a single pass. a | |
522 | * single pass will also be used to update all words that | |
523 | * are to have all their bits updated. | |
524 | */ | |
525 | for (rbits = nblks; rbits > 0; | |
526 | rbits -= nbits, dbitno += nbits) { | |
527 | /* determine the bit number within the word and | |
528 | * the number of bits within the word. | |
529 | */ | |
530 | wbitno = dbitno & (DBWORD - 1); | |
531 | nbits = min(rbits, DBWORD - wbitno); | |
532 | ||
533 | /* check if only part of the word is to be updated. */ | |
534 | if (nbits < DBWORD) { | |
535 | /* update (free or allocate) the bits | |
536 | * in this word. | |
537 | */ | |
538 | mask = | |
539 | (ONES << (DBWORD - nbits) >> wbitno); | |
540 | if (free) | |
541 | dp->pmap[word] &= | |
542 | cpu_to_le32(~mask); | |
543 | else | |
544 | dp->pmap[word] |= | |
545 | cpu_to_le32(mask); | |
546 | ||
547 | word += 1; | |
548 | } else { | |
549 | /* one or more words are to have all | |
550 | * their bits updated. determine how | |
551 | * many words and how many bits. | |
552 | */ | |
553 | nwords = rbits >> L2DBWORD; | |
554 | nbits = nwords << L2DBWORD; | |
555 | ||
556 | /* update (free or allocate) the bits | |
557 | * in these words. | |
558 | */ | |
559 | if (free) | |
560 | memset(&dp->pmap[word], 0, | |
561 | nwords * 4); | |
562 | else | |
563 | memset(&dp->pmap[word], (int) ONES, | |
564 | nwords * 4); | |
565 | ||
566 | word += nwords; | |
567 | } | |
568 | } | |
569 | ||
570 | /* | |
571 | * update dmap lsn | |
572 | */ | |
573 | if (lblkno == lastlblkno) | |
574 | continue; | |
575 | ||
576 | lastlblkno = lblkno; | |
577 | ||
578 | if (mp->lsn != 0) { | |
579 | /* inherit older/smaller lsn */ | |
580 | logdiff(diffp, mp->lsn, log); | |
581 | if (difft < diffp) { | |
582 | mp->lsn = lsn; | |
583 | ||
584 | /* move bp after tblock in logsync list */ | |
585 | LOGSYNC_LOCK(log); | |
586 | list_move(&mp->synclist, &tblk->synclist); | |
587 | LOGSYNC_UNLOCK(log); | |
588 | } | |
589 | ||
590 | /* inherit younger/larger clsn */ | |
591 | LOGSYNC_LOCK(log); | |
592 | logdiff(difft, tblk->clsn, log); | |
593 | logdiff(diffp, mp->clsn, log); | |
594 | if (difft > diffp) | |
595 | mp->clsn = tblk->clsn; | |
596 | LOGSYNC_UNLOCK(log); | |
597 | } else { | |
598 | mp->log = log; | |
599 | mp->lsn = lsn; | |
600 | ||
601 | /* insert bp after tblock in logsync list */ | |
602 | LOGSYNC_LOCK(log); | |
603 | ||
604 | log->count++; | |
605 | list_add(&mp->synclist, &tblk->synclist); | |
606 | ||
607 | mp->clsn = tblk->clsn; | |
608 | LOGSYNC_UNLOCK(log); | |
609 | } | |
610 | } | |
611 | ||
612 | /* write the last buffer. */ | |
613 | if (mp) { | |
614 | write_metapage(mp); | |
615 | } | |
616 | ||
617 | return (0); | |
618 | } | |
619 | ||
620 | ||
621 | /* | |
622 | * NAME: dbNextAG() | |
623 | * | |
624 | * FUNCTION: find the preferred allocation group for new allocations. | |
625 | * | |
626 | * Within the allocation groups, we maintain a preferred | |
627 | * allocation group which consists of a group with at least | |
628 | * average free space. It is the preferred group that we target | |
629 | * new inode allocation towards. The tie-in between inode | |
630 | * allocation and block allocation occurs as we allocate the | |
631 | * first (data) block of an inode and specify the inode (block) | |
632 | * as the allocation hint for this block. | |
633 | * | |
634 | * We try to avoid having more than one open file growing in | |
635 | * an allocation group, as this will lead to fragmentation. | |
636 | * This differs from the old OS/2 method of trying to keep | |
637 | * empty ags around for large allocations. | |
638 | * | |
639 | * PARAMETERS: | |
640 | * ipbmap - pointer to in-core inode for the block map. | |
641 | * | |
642 | * RETURN VALUES: | |
643 | * the preferred allocation group number. | |
644 | */ | |
645 | int dbNextAG(struct inode *ipbmap) | |
646 | { | |
647 | s64 avgfree; | |
648 | int agpref; | |
649 | s64 hwm = 0; | |
650 | int i; | |
651 | int next_best = -1; | |
652 | struct bmap *bmp = JFS_SBI(ipbmap->i_sb)->bmap; | |
653 | ||
654 | BMAP_LOCK(bmp); | |
655 | ||
656 | /* determine the average number of free blocks within the ags. */ | |
657 | avgfree = (u32)bmp->db_nfree / bmp->db_numag; | |
658 | ||
659 | /* | |
660 | * if the current preferred ag does not have an active allocator | |
661 | * and has at least average freespace, return it | |
662 | */ | |
663 | agpref = bmp->db_agpref; | |
664 | if ((atomic_read(&bmp->db_active[agpref]) == 0) && | |
665 | (bmp->db_agfree[agpref] >= avgfree)) | |
666 | goto unlock; | |
667 | ||
668 | /* From the last preferred ag, find the next one with at least | |
669 | * average free space. | |
670 | */ | |
671 | for (i = 0 ; i < bmp->db_numag; i++, agpref++) { | |
672 | if (agpref == bmp->db_numag) | |
673 | agpref = 0; | |
674 | ||
675 | if (atomic_read(&bmp->db_active[agpref])) | |
676 | /* open file is currently growing in this ag */ | |
677 | continue; | |
678 | if (bmp->db_agfree[agpref] >= avgfree) { | |
679 | /* Return this one */ | |
680 | bmp->db_agpref = agpref; | |
681 | goto unlock; | |
682 | } else if (bmp->db_agfree[agpref] > hwm) { | |
683 | /* Less than avg. freespace, but best so far */ | |
684 | hwm = bmp->db_agfree[agpref]; | |
685 | next_best = agpref; | |
686 | } | |
687 | } | |
688 | ||
689 | /* | |
690 | * If no inactive ag was found with average freespace, use the | |
691 | * next best | |
692 | */ | |
693 | if (next_best != -1) | |
694 | bmp->db_agpref = next_best; | |
695 | /* else leave db_agpref unchanged */ | |
696 | unlock: | |
697 | BMAP_UNLOCK(bmp); | |
698 | ||
699 | /* return the preferred group. | |
700 | */ | |
701 | return (bmp->db_agpref); | |
702 | } | |
703 | ||
704 | /* | |
705 | * NAME: dbAlloc() | |
706 | * | |
707 | * FUNCTION: attempt to allocate a specified number of contiguous free | |
708 | * blocks from the working allocation block map. | |
709 | * | |
710 | * the block allocation policy uses hints and a multi-step | |
711 | * approach. | |
712 | * | |
713 | * for allocation requests smaller than the number of blocks | |
714 | * per dmap, we first try to allocate the new blocks | |
715 | * immediately following the hint. if these blocks are not | |
716 | * available, we try to allocate blocks near the hint. if | |
717 | * no blocks near the hint are available, we next try to | |
718 | * allocate within the same dmap as contains the hint. | |
719 | * | |
720 | * if no blocks are available in the dmap or the allocation | |
721 | * request is larger than the dmap size, we try to allocate | |
722 | * within the same allocation group as contains the hint. if | |
723 | * this does not succeed, we finally try to allocate anywhere | |
724 | * within the aggregate. | |
725 | * | |
726 | * we also try to allocate anywhere within the aggregate for | |
727 | * for allocation requests larger than the allocation group | |
728 | * size or requests that specify no hint value. | |
729 | * | |
730 | * PARAMETERS: | |
731 | * ip - pointer to in-core inode; | |
732 | * hint - allocation hint. | |
733 | * nblocks - number of contiguous blocks in the range. | |
734 | * results - on successful return, set to the starting block number | |
735 | * of the newly allocated contiguous range. | |
736 | * | |
737 | * RETURN VALUES: | |
738 | * 0 - success | |
739 | * -ENOSPC - insufficient disk resources | |
740 | * -EIO - i/o error | |
741 | */ | |
742 | int dbAlloc(struct inode *ip, s64 hint, s64 nblocks, s64 * results) | |
743 | { | |
744 | int rc, agno; | |
745 | struct inode *ipbmap = JFS_SBI(ip->i_sb)->ipbmap; | |
746 | struct bmap *bmp; | |
747 | struct metapage *mp; | |
748 | s64 lblkno, blkno; | |
749 | struct dmap *dp; | |
750 | int l2nb; | |
751 | s64 mapSize; | |
752 | int writers; | |
753 | ||
754 | /* assert that nblocks is valid */ | |
755 | assert(nblocks > 0); | |
756 | ||
757 | #ifdef _STILL_TO_PORT | |
758 | /* DASD limit check F226941 */ | |
759 | if (OVER_LIMIT(ip, nblocks)) | |
760 | return -ENOSPC; | |
761 | #endif /* _STILL_TO_PORT */ | |
762 | ||
763 | /* get the log2 number of blocks to be allocated. | |
764 | * if the number of blocks is not a log2 multiple, | |
765 | * it will be rounded up to the next log2 multiple. | |
766 | */ | |
767 | l2nb = BLKSTOL2(nblocks); | |
768 | ||
769 | bmp = JFS_SBI(ip->i_sb)->bmap; | |
770 | ||
771 | //retry: /* serialize w.r.t.extendfs() */ | |
772 | mapSize = bmp->db_mapsize; | |
773 | ||
774 | /* the hint should be within the map */ | |
775 | if (hint >= mapSize) { | |
776 | jfs_error(ip->i_sb, "dbAlloc: the hint is outside the map"); | |
777 | return -EIO; | |
778 | } | |
779 | ||
780 | /* if the number of blocks to be allocated is greater than the | |
781 | * allocation group size, try to allocate anywhere. | |
782 | */ | |
783 | if (l2nb > bmp->db_agl2size) { | |
784 | IWRITE_LOCK(ipbmap); | |
785 | ||
786 | rc = dbAllocAny(bmp, nblocks, l2nb, results); | |
787 | if (rc == 0) { | |
788 | DBALLOC(bmp->db_DBmap, bmp->db_mapsize, *results, | |
789 | nblocks); | |
790 | } | |
791 | ||
792 | goto write_unlock; | |
793 | } | |
794 | ||
795 | /* | |
796 | * If no hint, let dbNextAG recommend an allocation group | |
797 | */ | |
798 | if (hint == 0) | |
799 | goto pref_ag; | |
800 | ||
801 | /* we would like to allocate close to the hint. adjust the | |
802 | * hint to the block following the hint since the allocators | |
803 | * will start looking for free space starting at this point. | |
804 | */ | |
805 | blkno = hint + 1; | |
806 | ||
807 | if (blkno >= bmp->db_mapsize) | |
808 | goto pref_ag; | |
809 | ||
810 | agno = blkno >> bmp->db_agl2size; | |
811 | ||
812 | /* check if blkno crosses over into a new allocation group. | |
813 | * if so, check if we should allow allocations within this | |
814 | * allocation group. | |
815 | */ | |
816 | if ((blkno & (bmp->db_agsize - 1)) == 0) | |
817 | /* check if the AG is currenly being written to. | |
818 | * if so, call dbNextAG() to find a non-busy | |
819 | * AG with sufficient free space. | |
820 | */ | |
821 | if (atomic_read(&bmp->db_active[agno])) | |
822 | goto pref_ag; | |
823 | ||
824 | /* check if the allocation request size can be satisfied from a | |
825 | * single dmap. if so, try to allocate from the dmap containing | |
826 | * the hint using a tiered strategy. | |
827 | */ | |
828 | if (nblocks <= BPERDMAP) { | |
829 | IREAD_LOCK(ipbmap); | |
830 | ||
831 | /* get the buffer for the dmap containing the hint. | |
832 | */ | |
833 | rc = -EIO; | |
834 | lblkno = BLKTODMAP(blkno, bmp->db_l2nbperpage); | |
835 | mp = read_metapage(ipbmap, lblkno, PSIZE, 0); | |
836 | if (mp == NULL) | |
837 | goto read_unlock; | |
838 | ||
839 | dp = (struct dmap *) mp->data; | |
840 | ||
841 | /* first, try to satisfy the allocation request with the | |
842 | * blocks beginning at the hint. | |
843 | */ | |
844 | if ((rc = dbAllocNext(bmp, dp, blkno, (int) nblocks)) | |
845 | != -ENOSPC) { | |
846 | if (rc == 0) { | |
847 | *results = blkno; | |
848 | DBALLOC(bmp->db_DBmap, bmp->db_mapsize, | |
849 | *results, nblocks); | |
850 | mark_metapage_dirty(mp); | |
851 | } | |
852 | ||
853 | release_metapage(mp); | |
854 | goto read_unlock; | |
855 | } | |
856 | ||
857 | writers = atomic_read(&bmp->db_active[agno]); | |
858 | if ((writers > 1) || | |
859 | ((writers == 1) && (JFS_IP(ip)->active_ag != agno))) { | |
860 | /* | |
861 | * Someone else is writing in this allocation | |
862 | * group. To avoid fragmenting, try another ag | |
863 | */ | |
864 | release_metapage(mp); | |
865 | IREAD_UNLOCK(ipbmap); | |
866 | goto pref_ag; | |
867 | } | |
868 | ||
869 | /* next, try to satisfy the allocation request with blocks | |
870 | * near the hint. | |
871 | */ | |
872 | if ((rc = | |
873 | dbAllocNear(bmp, dp, blkno, (int) nblocks, l2nb, results)) | |
874 | != -ENOSPC) { | |
875 | if (rc == 0) { | |
876 | DBALLOC(bmp->db_DBmap, bmp->db_mapsize, | |
877 | *results, nblocks); | |
878 | mark_metapage_dirty(mp); | |
879 | } | |
880 | ||
881 | release_metapage(mp); | |
882 | goto read_unlock; | |
883 | } | |
884 | ||
885 | /* try to satisfy the allocation request with blocks within | |
886 | * the same dmap as the hint. | |
887 | */ | |
888 | if ((rc = dbAllocDmapLev(bmp, dp, (int) nblocks, l2nb, results)) | |
889 | != -ENOSPC) { | |
890 | if (rc == 0) { | |
891 | DBALLOC(bmp->db_DBmap, bmp->db_mapsize, | |
892 | *results, nblocks); | |
893 | mark_metapage_dirty(mp); | |
894 | } | |
895 | ||
896 | release_metapage(mp); | |
897 | goto read_unlock; | |
898 | } | |
899 | ||
900 | release_metapage(mp); | |
901 | IREAD_UNLOCK(ipbmap); | |
902 | } | |
903 | ||
904 | /* try to satisfy the allocation request with blocks within | |
905 | * the same allocation group as the hint. | |
906 | */ | |
907 | IWRITE_LOCK(ipbmap); | |
908 | if ((rc = dbAllocAG(bmp, agno, nblocks, l2nb, results)) | |
909 | != -ENOSPC) { | |
910 | if (rc == 0) | |
911 | DBALLOC(bmp->db_DBmap, bmp->db_mapsize, | |
912 | *results, nblocks); | |
913 | goto write_unlock; | |
914 | } | |
915 | IWRITE_UNLOCK(ipbmap); | |
916 | ||
917 | ||
918 | pref_ag: | |
919 | /* | |
920 | * Let dbNextAG recommend a preferred allocation group | |
921 | */ | |
922 | agno = dbNextAG(ipbmap); | |
923 | IWRITE_LOCK(ipbmap); | |
924 | ||
925 | /* Try to allocate within this allocation group. if that fails, try to | |
926 | * allocate anywhere in the map. | |
927 | */ | |
928 | if ((rc = dbAllocAG(bmp, agno, nblocks, l2nb, results)) == -ENOSPC) | |
929 | rc = dbAllocAny(bmp, nblocks, l2nb, results); | |
930 | if (rc == 0) { | |
931 | DBALLOC(bmp->db_DBmap, bmp->db_mapsize, *results, nblocks); | |
932 | } | |
933 | ||
934 | write_unlock: | |
935 | IWRITE_UNLOCK(ipbmap); | |
936 | ||
937 | return (rc); | |
938 | ||
939 | read_unlock: | |
940 | IREAD_UNLOCK(ipbmap); | |
941 | ||
942 | return (rc); | |
943 | } | |
944 | ||
945 | #ifdef _NOTYET | |
946 | /* | |
947 | * NAME: dbAllocExact() | |
948 | * | |
949 | * FUNCTION: try to allocate the requested extent; | |
950 | * | |
951 | * PARAMETERS: | |
952 | * ip - pointer to in-core inode; | |
953 | * blkno - extent address; | |
954 | * nblocks - extent length; | |
955 | * | |
956 | * RETURN VALUES: | |
957 | * 0 - success | |
958 | * -ENOSPC - insufficient disk resources | |
959 | * -EIO - i/o error | |
960 | */ | |
961 | int dbAllocExact(struct inode *ip, s64 blkno, int nblocks) | |
962 | { | |
963 | int rc; | |
964 | struct inode *ipbmap = JFS_SBI(ip->i_sb)->ipbmap; | |
965 | struct bmap *bmp = JFS_SBI(ip->i_sb)->bmap; | |
966 | struct dmap *dp; | |
967 | s64 lblkno; | |
968 | struct metapage *mp; | |
969 | ||
970 | IREAD_LOCK(ipbmap); | |
971 | ||
972 | /* | |
973 | * validate extent request: | |
974 | * | |
975 | * note: defragfs policy: | |
976 | * max 64 blocks will be moved. | |
977 | * allocation request size must be satisfied from a single dmap. | |
978 | */ | |
979 | if (nblocks <= 0 || nblocks > BPERDMAP || blkno >= bmp->db_mapsize) { | |
980 | IREAD_UNLOCK(ipbmap); | |
981 | return -EINVAL; | |
982 | } | |
983 | ||
984 | if (nblocks > ((s64) 1 << bmp->db_maxfreebud)) { | |
985 | /* the free space is no longer available */ | |
986 | IREAD_UNLOCK(ipbmap); | |
987 | return -ENOSPC; | |
988 | } | |
989 | ||
990 | /* read in the dmap covering the extent */ | |
991 | lblkno = BLKTODMAP(blkno, bmp->db_l2nbperpage); | |
992 | mp = read_metapage(ipbmap, lblkno, PSIZE, 0); | |
993 | if (mp == NULL) { | |
994 | IREAD_UNLOCK(ipbmap); | |
995 | return -EIO; | |
996 | } | |
997 | dp = (struct dmap *) mp->data; | |
998 | ||
999 | /* try to allocate the requested extent */ | |
1000 | rc = dbAllocNext(bmp, dp, blkno, nblocks); | |
1001 | ||
1002 | IREAD_UNLOCK(ipbmap); | |
1003 | ||
1004 | if (rc == 0) { | |
1005 | DBALLOC(bmp->db_DBmap, bmp->db_mapsize, blkno, nblocks); | |
1006 | mark_metapage_dirty(mp); | |
1007 | } | |
1008 | release_metapage(mp); | |
1009 | ||
1010 | return (rc); | |
1011 | } | |
1012 | #endif /* _NOTYET */ | |
1013 | ||
1014 | /* | |
1015 | * NAME: dbReAlloc() | |
1016 | * | |
1017 | * FUNCTION: attempt to extend a current allocation by a specified | |
1018 | * number of blocks. | |
1019 | * | |
1020 | * this routine attempts to satisfy the allocation request | |
1021 | * by first trying to extend the existing allocation in | |
1022 | * place by allocating the additional blocks as the blocks | |
1023 | * immediately following the current allocation. if these | |
1024 | * blocks are not available, this routine will attempt to | |
1025 | * allocate a new set of contiguous blocks large enough | |
1026 | * to cover the existing allocation plus the additional | |
1027 | * number of blocks required. | |
1028 | * | |
1029 | * PARAMETERS: | |
1030 | * ip - pointer to in-core inode requiring allocation. | |
1031 | * blkno - starting block of the current allocation. | |
1032 | * nblocks - number of contiguous blocks within the current | |
1033 | * allocation. | |
1034 | * addnblocks - number of blocks to add to the allocation. | |
1035 | * results - on successful return, set to the starting block number | |
1036 | * of the existing allocation if the existing allocation | |
1037 | * was extended in place or to a newly allocated contiguous | |
1038 | * range if the existing allocation could not be extended | |
1039 | * in place. | |
1040 | * | |
1041 | * RETURN VALUES: | |
1042 | * 0 - success | |
1043 | * -ENOSPC - insufficient disk resources | |
1044 | * -EIO - i/o error | |
1045 | */ | |
1046 | int | |
1047 | dbReAlloc(struct inode *ip, | |
1048 | s64 blkno, s64 nblocks, s64 addnblocks, s64 * results) | |
1049 | { | |
1050 | int rc; | |
1051 | ||
1052 | /* try to extend the allocation in place. | |
1053 | */ | |
1054 | if ((rc = dbExtend(ip, blkno, nblocks, addnblocks)) == 0) { | |
1055 | *results = blkno; | |
1056 | return (0); | |
1057 | } else { | |
1058 | if (rc != -ENOSPC) | |
1059 | return (rc); | |
1060 | } | |
1061 | ||
1062 | /* could not extend the allocation in place, so allocate a | |
1063 | * new set of blocks for the entire request (i.e. try to get | |
1064 | * a range of contiguous blocks large enough to cover the | |
1065 | * existing allocation plus the additional blocks.) | |
1066 | */ | |
1067 | return (dbAlloc | |
1068 | (ip, blkno + nblocks - 1, addnblocks + nblocks, results)); | |
1069 | } | |
1070 | ||
1071 | ||
1072 | /* | |
1073 | * NAME: dbExtend() | |
1074 | * | |
1075 | * FUNCTION: attempt to extend a current allocation by a specified | |
1076 | * number of blocks. | |
1077 | * | |
1078 | * this routine attempts to satisfy the allocation request | |
1079 | * by first trying to extend the existing allocation in | |
1080 | * place by allocating the additional blocks as the blocks | |
1081 | * immediately following the current allocation. | |
1082 | * | |
1083 | * PARAMETERS: | |
1084 | * ip - pointer to in-core inode requiring allocation. | |
1085 | * blkno - starting block of the current allocation. | |
1086 | * nblocks - number of contiguous blocks within the current | |
1087 | * allocation. | |
1088 | * addnblocks - number of blocks to add to the allocation. | |
1089 | * | |
1090 | * RETURN VALUES: | |
1091 | * 0 - success | |
1092 | * -ENOSPC - insufficient disk resources | |
1093 | * -EIO - i/o error | |
1094 | */ | |
1095 | static int dbExtend(struct inode *ip, s64 blkno, s64 nblocks, s64 addnblocks) | |
1096 | { | |
1097 | struct jfs_sb_info *sbi = JFS_SBI(ip->i_sb); | |
1098 | s64 lblkno, lastblkno, extblkno; | |
1099 | uint rel_block; | |
1100 | struct metapage *mp; | |
1101 | struct dmap *dp; | |
1102 | int rc; | |
1103 | struct inode *ipbmap = sbi->ipbmap; | |
1104 | struct bmap *bmp; | |
1105 | ||
1106 | /* | |
1107 | * We don't want a non-aligned extent to cross a page boundary | |
1108 | */ | |
1109 | if (((rel_block = blkno & (sbi->nbperpage - 1))) && | |
1110 | (rel_block + nblocks + addnblocks > sbi->nbperpage)) | |
1111 | return -ENOSPC; | |
1112 | ||
1113 | /* get the last block of the current allocation */ | |
1114 | lastblkno = blkno + nblocks - 1; | |
1115 | ||
1116 | /* determine the block number of the block following | |
1117 | * the existing allocation. | |
1118 | */ | |
1119 | extblkno = lastblkno + 1; | |
1120 | ||
1121 | IREAD_LOCK(ipbmap); | |
1122 | ||
1123 | /* better be within the file system */ | |
1124 | bmp = sbi->bmap; | |
1125 | if (lastblkno < 0 || lastblkno >= bmp->db_mapsize) { | |
1126 | IREAD_UNLOCK(ipbmap); | |
1127 | jfs_error(ip->i_sb, | |
1128 | "dbExtend: the block is outside the filesystem"); | |
1129 | return -EIO; | |
1130 | } | |
1131 | ||
1132 | /* we'll attempt to extend the current allocation in place by | |
1133 | * allocating the additional blocks as the blocks immediately | |
1134 | * following the current allocation. we only try to extend the | |
1135 | * current allocation in place if the number of additional blocks | |
1136 | * can fit into a dmap, the last block of the current allocation | |
1137 | * is not the last block of the file system, and the start of the | |
1138 | * inplace extension is not on an allocation group boundary. | |
1139 | */ | |
1140 | if (addnblocks > BPERDMAP || extblkno >= bmp->db_mapsize || | |
1141 | (extblkno & (bmp->db_agsize - 1)) == 0) { | |
1142 | IREAD_UNLOCK(ipbmap); | |
1143 | return -ENOSPC; | |
1144 | } | |
1145 | ||
1146 | /* get the buffer for the dmap containing the first block | |
1147 | * of the extension. | |
1148 | */ | |
1149 | lblkno = BLKTODMAP(extblkno, bmp->db_l2nbperpage); | |
1150 | mp = read_metapage(ipbmap, lblkno, PSIZE, 0); | |
1151 | if (mp == NULL) { | |
1152 | IREAD_UNLOCK(ipbmap); | |
1153 | return -EIO; | |
1154 | } | |
1155 | ||
1156 | DBALLOCCK(bmp->db_DBmap, bmp->db_mapsize, blkno, nblocks); | |
1157 | dp = (struct dmap *) mp->data; | |
1158 | ||
1159 | /* try to allocate the blocks immediately following the | |
1160 | * current allocation. | |
1161 | */ | |
1162 | rc = dbAllocNext(bmp, dp, extblkno, (int) addnblocks); | |
1163 | ||
1164 | IREAD_UNLOCK(ipbmap); | |
1165 | ||
1166 | /* were we successful ? */ | |
1167 | if (rc == 0) { | |
1168 | DBALLOC(bmp->db_DBmap, bmp->db_mapsize, extblkno, | |
1169 | addnblocks); | |
1170 | write_metapage(mp); | |
1171 | } else | |
1172 | /* we were not successful */ | |
1173 | release_metapage(mp); | |
1174 | ||
1175 | ||
1176 | return (rc); | |
1177 | } | |
1178 | ||
1179 | ||
1180 | /* | |
1181 | * NAME: dbAllocNext() | |
1182 | * | |
1183 | * FUNCTION: attempt to allocate the blocks of the specified block | |
1184 | * range within a dmap. | |
1185 | * | |
1186 | * PARAMETERS: | |
1187 | * bmp - pointer to bmap descriptor | |
1188 | * dp - pointer to dmap. | |
1189 | * blkno - starting block number of the range. | |
1190 | * nblocks - number of contiguous free blocks of the range. | |
1191 | * | |
1192 | * RETURN VALUES: | |
1193 | * 0 - success | |
1194 | * -ENOSPC - insufficient disk resources | |
1195 | * -EIO - i/o error | |
1196 | * | |
1197 | * serialization: IREAD_LOCK(ipbmap) held on entry/exit; | |
1198 | */ | |
1199 | static int dbAllocNext(struct bmap * bmp, struct dmap * dp, s64 blkno, | |
1200 | int nblocks) | |
1201 | { | |
1202 | int dbitno, word, rembits, nb, nwords, wbitno, nw; | |
1203 | int l2size; | |
1204 | s8 *leaf; | |
1205 | u32 mask; | |
1206 | ||
1207 | if (dp->tree.leafidx != cpu_to_le32(LEAFIND)) { | |
1208 | jfs_error(bmp->db_ipbmap->i_sb, | |
1209 | "dbAllocNext: Corrupt dmap page"); | |
1210 | return -EIO; | |
1211 | } | |
1212 | ||
1213 | /* pick up a pointer to the leaves of the dmap tree. | |
1214 | */ | |
1215 | leaf = dp->tree.stree + le32_to_cpu(dp->tree.leafidx); | |
1216 | ||
1217 | /* determine the bit number and word within the dmap of the | |
1218 | * starting block. | |
1219 | */ | |
1220 | dbitno = blkno & (BPERDMAP - 1); | |
1221 | word = dbitno >> L2DBWORD; | |
1222 | ||
1223 | /* check if the specified block range is contained within | |
1224 | * this dmap. | |
1225 | */ | |
1226 | if (dbitno + nblocks > BPERDMAP) | |
1227 | return -ENOSPC; | |
1228 | ||
1229 | /* check if the starting leaf indicates that anything | |
1230 | * is free. | |
1231 | */ | |
1232 | if (leaf[word] == NOFREE) | |
1233 | return -ENOSPC; | |
1234 | ||
1235 | /* check the dmaps words corresponding to block range to see | |
1236 | * if the block range is free. not all bits of the first and | |
1237 | * last words may be contained within the block range. if this | |
1238 | * is the case, we'll work against those words (i.e. partial first | |
1239 | * and/or last) on an individual basis (a single pass) and examine | |
1240 | * the actual bits to determine if they are free. a single pass | |
1241 | * will be used for all dmap words fully contained within the | |
1242 | * specified range. within this pass, the leaves of the dmap | |
1243 | * tree will be examined to determine if the blocks are free. a | |
1244 | * single leaf may describe the free space of multiple dmap | |
1245 | * words, so we may visit only a subset of the actual leaves | |
1246 | * corresponding to the dmap words of the block range. | |
1247 | */ | |
1248 | for (rembits = nblocks; rembits > 0; rembits -= nb, dbitno += nb) { | |
1249 | /* determine the bit number within the word and | |
1250 | * the number of bits within the word. | |
1251 | */ | |
1252 | wbitno = dbitno & (DBWORD - 1); | |
1253 | nb = min(rembits, DBWORD - wbitno); | |
1254 | ||
1255 | /* check if only part of the word is to be examined. | |
1256 | */ | |
1257 | if (nb < DBWORD) { | |
1258 | /* check if the bits are free. | |
1259 | */ | |
1260 | mask = (ONES << (DBWORD - nb) >> wbitno); | |
1261 | if ((mask & ~le32_to_cpu(dp->wmap[word])) != mask) | |
1262 | return -ENOSPC; | |
1263 | ||
1264 | word += 1; | |
1265 | } else { | |
1266 | /* one or more dmap words are fully contained | |
1267 | * within the block range. determine how many | |
1268 | * words and how many bits. | |
1269 | */ | |
1270 | nwords = rembits >> L2DBWORD; | |
1271 | nb = nwords << L2DBWORD; | |
1272 | ||
1273 | /* now examine the appropriate leaves to determine | |
1274 | * if the blocks are free. | |
1275 | */ | |
1276 | while (nwords > 0) { | |
1277 | /* does the leaf describe any free space ? | |
1278 | */ | |
1279 | if (leaf[word] < BUDMIN) | |
1280 | return -ENOSPC; | |
1281 | ||
1282 | /* determine the l2 number of bits provided | |
1283 | * by this leaf. | |
1284 | */ | |
1285 | l2size = | |
1286 | min((int)leaf[word], NLSTOL2BSZ(nwords)); | |
1287 | ||
1288 | /* determine how many words were handled. | |
1289 | */ | |
1290 | nw = BUDSIZE(l2size, BUDMIN); | |
1291 | ||
1292 | nwords -= nw; | |
1293 | word += nw; | |
1294 | } | |
1295 | } | |
1296 | } | |
1297 | ||
1298 | /* allocate the blocks. | |
1299 | */ | |
1300 | return (dbAllocDmap(bmp, dp, blkno, nblocks)); | |
1301 | } | |
1302 | ||
1303 | ||
1304 | /* | |
1305 | * NAME: dbAllocNear() | |
1306 | * | |
1307 | * FUNCTION: attempt to allocate a number of contiguous free blocks near | |
1308 | * a specified block (hint) within a dmap. | |
1309 | * | |
1310 | * starting with the dmap leaf that covers the hint, we'll | |
1311 | * check the next four contiguous leaves for sufficient free | |
1312 | * space. if sufficient free space is found, we'll allocate | |
1313 | * the desired free space. | |
1314 | * | |
1315 | * PARAMETERS: | |
1316 | * bmp - pointer to bmap descriptor | |
1317 | * dp - pointer to dmap. | |
1318 | * blkno - block number to allocate near. | |
1319 | * nblocks - actual number of contiguous free blocks desired. | |
1320 | * l2nb - log2 number of contiguous free blocks desired. | |
1321 | * results - on successful return, set to the starting block number | |
1322 | * of the newly allocated range. | |
1323 | * | |
1324 | * RETURN VALUES: | |
1325 | * 0 - success | |
1326 | * -ENOSPC - insufficient disk resources | |
1327 | * -EIO - i/o error | |
1328 | * | |
1329 | * serialization: IREAD_LOCK(ipbmap) held on entry/exit; | |
1330 | */ | |
1331 | static int | |
1332 | dbAllocNear(struct bmap * bmp, | |
1333 | struct dmap * dp, s64 blkno, int nblocks, int l2nb, s64 * results) | |
1334 | { | |
1335 | int word, lword, rc; | |
1336 | s8 *leaf; | |
1337 | ||
1338 | if (dp->tree.leafidx != cpu_to_le32(LEAFIND)) { | |
1339 | jfs_error(bmp->db_ipbmap->i_sb, | |
1340 | "dbAllocNear: Corrupt dmap page"); | |
1341 | return -EIO; | |
1342 | } | |
1343 | ||
1344 | leaf = dp->tree.stree + le32_to_cpu(dp->tree.leafidx); | |
1345 | ||
1346 | /* determine the word within the dmap that holds the hint | |
1347 | * (i.e. blkno). also, determine the last word in the dmap | |
1348 | * that we'll include in our examination. | |
1349 | */ | |
1350 | word = (blkno & (BPERDMAP - 1)) >> L2DBWORD; | |
1351 | lword = min(word + 4, LPERDMAP); | |
1352 | ||
1353 | /* examine the leaves for sufficient free space. | |
1354 | */ | |
1355 | for (; word < lword; word++) { | |
1356 | /* does the leaf describe sufficient free space ? | |
1357 | */ | |
1358 | if (leaf[word] < l2nb) | |
1359 | continue; | |
1360 | ||
1361 | /* determine the block number within the file system | |
1362 | * of the first block described by this dmap word. | |
1363 | */ | |
1364 | blkno = le64_to_cpu(dp->start) + (word << L2DBWORD); | |
1365 | ||
1366 | /* if not all bits of the dmap word are free, get the | |
1367 | * starting bit number within the dmap word of the required | |
1368 | * string of free bits and adjust the block number with the | |
1369 | * value. | |
1370 | */ | |
1371 | if (leaf[word] < BUDMIN) | |
1372 | blkno += | |
1373 | dbFindBits(le32_to_cpu(dp->wmap[word]), l2nb); | |
1374 | ||
1375 | /* allocate the blocks. | |
1376 | */ | |
1377 | if ((rc = dbAllocDmap(bmp, dp, blkno, nblocks)) == 0) | |
1378 | *results = blkno; | |
1379 | ||
1380 | return (rc); | |
1381 | } | |
1382 | ||
1383 | return -ENOSPC; | |
1384 | } | |
1385 | ||
1386 | ||
1387 | /* | |
1388 | * NAME: dbAllocAG() | |
1389 | * | |
1390 | * FUNCTION: attempt to allocate the specified number of contiguous | |
1391 | * free blocks within the specified allocation group. | |
1392 | * | |
1393 | * unless the allocation group size is equal to the number | |
1394 | * of blocks per dmap, the dmap control pages will be used to | |
1395 | * find the required free space, if available. we start the | |
1396 | * search at the highest dmap control page level which | |
1397 | * distinctly describes the allocation group's free space | |
1398 | * (i.e. the highest level at which the allocation group's | |
1399 | * free space is not mixed in with that of any other group). | |
1400 | * in addition, we start the search within this level at a | |
1401 | * height of the dmapctl dmtree at which the nodes distinctly | |
1402 | * describe the allocation group's free space. at this height, | |
1403 | * the allocation group's free space may be represented by 1 | |
1404 | * or two sub-trees, depending on the allocation group size. | |
1405 | * we search the top nodes of these subtrees left to right for | |
1406 | * sufficient free space. if sufficient free space is found, | |
1407 | * the subtree is searched to find the leftmost leaf that | |
1408 | * has free space. once we have made it to the leaf, we | |
1409 | * move the search to the next lower level dmap control page | |
1410 | * corresponding to this leaf. we continue down the dmap control | |
1411 | * pages until we find the dmap that contains or starts the | |
1412 | * sufficient free space and we allocate at this dmap. | |
1413 | * | |
1414 | * if the allocation group size is equal to the dmap size, | |
1415 | * we'll start at the dmap corresponding to the allocation | |
1416 | * group and attempt the allocation at this level. | |
1417 | * | |
1418 | * the dmap control page search is also not performed if the | |
1419 | * allocation group is completely free and we go to the first | |
1420 | * dmap of the allocation group to do the allocation. this is | |
1421 | * done because the allocation group may be part (not the first | |
1422 | * part) of a larger binary buddy system, causing the dmap | |
1423 | * control pages to indicate no free space (NOFREE) within | |
1424 | * the allocation group. | |
1425 | * | |
1426 | * PARAMETERS: | |
1427 | * bmp - pointer to bmap descriptor | |
1428 | * agno - allocation group number. | |
1429 | * nblocks - actual number of contiguous free blocks desired. | |
1430 | * l2nb - log2 number of contiguous free blocks desired. | |
1431 | * results - on successful return, set to the starting block number | |
1432 | * of the newly allocated range. | |
1433 | * | |
1434 | * RETURN VALUES: | |
1435 | * 0 - success | |
1436 | * -ENOSPC - insufficient disk resources | |
1437 | * -EIO - i/o error | |
1438 | * | |
1439 | * note: IWRITE_LOCK(ipmap) held on entry/exit; | |
1440 | */ | |
1441 | static int | |
1442 | dbAllocAG(struct bmap * bmp, int agno, s64 nblocks, int l2nb, s64 * results) | |
1443 | { | |
1444 | struct metapage *mp; | |
1445 | struct dmapctl *dcp; | |
1446 | int rc, ti, i, k, m, n, agperlev; | |
1447 | s64 blkno, lblkno; | |
1448 | int budmin; | |
1449 | ||
1450 | /* allocation request should not be for more than the | |
1451 | * allocation group size. | |
1452 | */ | |
1453 | if (l2nb > bmp->db_agl2size) { | |
1454 | jfs_error(bmp->db_ipbmap->i_sb, | |
1455 | "dbAllocAG: allocation request is larger than the " | |
1456 | "allocation group size"); | |
1457 | return -EIO; | |
1458 | } | |
1459 | ||
1460 | /* determine the starting block number of the allocation | |
1461 | * group. | |
1462 | */ | |
1463 | blkno = (s64) agno << bmp->db_agl2size; | |
1464 | ||
1465 | /* check if the allocation group size is the minimum allocation | |
1466 | * group size or if the allocation group is completely free. if | |
1467 | * the allocation group size is the minimum size of BPERDMAP (i.e. | |
1468 | * 1 dmap), there is no need to search the dmap control page (below) | |
1469 | * that fully describes the allocation group since the allocation | |
1470 | * group is already fully described by a dmap. in this case, we | |
1471 | * just call dbAllocCtl() to search the dmap tree and allocate the | |
1472 | * required space if available. | |
1473 | * | |
1474 | * if the allocation group is completely free, dbAllocCtl() is | |
1475 | * also called to allocate the required space. this is done for | |
1476 | * two reasons. first, it makes no sense searching the dmap control | |
1477 | * pages for free space when we know that free space exists. second, | |
1478 | * the dmap control pages may indicate that the allocation group | |
1479 | * has no free space if the allocation group is part (not the first | |
1480 | * part) of a larger binary buddy system. | |
1481 | */ | |
1482 | if (bmp->db_agsize == BPERDMAP | |
1483 | || bmp->db_agfree[agno] == bmp->db_agsize) { | |
1484 | rc = dbAllocCtl(bmp, nblocks, l2nb, blkno, results); | |
1485 | if ((rc == -ENOSPC) && | |
1486 | (bmp->db_agfree[agno] == bmp->db_agsize)) { | |
1487 | printk(KERN_ERR "blkno = %Lx, blocks = %Lx\n", | |
1488 | (unsigned long long) blkno, | |
1489 | (unsigned long long) nblocks); | |
1490 | jfs_error(bmp->db_ipbmap->i_sb, | |
1491 | "dbAllocAG: dbAllocCtl failed in free AG"); | |
1492 | } | |
1493 | return (rc); | |
1494 | } | |
1495 | ||
1496 | /* the buffer for the dmap control page that fully describes the | |
1497 | * allocation group. | |
1498 | */ | |
1499 | lblkno = BLKTOCTL(blkno, bmp->db_l2nbperpage, bmp->db_aglevel); | |
1500 | mp = read_metapage(bmp->db_ipbmap, lblkno, PSIZE, 0); | |
1501 | if (mp == NULL) | |
1502 | return -EIO; | |
1503 | dcp = (struct dmapctl *) mp->data; | |
1504 | budmin = dcp->budmin; | |
1505 | ||
1506 | if (dcp->leafidx != cpu_to_le32(CTLLEAFIND)) { | |
1507 | jfs_error(bmp->db_ipbmap->i_sb, | |
1508 | "dbAllocAG: Corrupt dmapctl page"); | |
1509 | release_metapage(mp); | |
1510 | return -EIO; | |
1511 | } | |
1512 | ||
1513 | /* search the subtree(s) of the dmap control page that describes | |
1514 | * the allocation group, looking for sufficient free space. to begin, | |
1515 | * determine how many allocation groups are represented in a dmap | |
1516 | * control page at the control page level (i.e. L0, L1, L2) that | |
1517 | * fully describes an allocation group. next, determine the starting | |
1518 | * tree index of this allocation group within the control page. | |
1519 | */ | |
1520 | agperlev = | |
1521 | (1 << (L2LPERCTL - (bmp->db_agheigth << 1))) / bmp->db_agwidth; | |
1522 | ti = bmp->db_agstart + bmp->db_agwidth * (agno & (agperlev - 1)); | |
1523 | ||
1524 | /* dmap control page trees fan-out by 4 and a single allocation | |
1525 | * group may be described by 1 or 2 subtrees within the ag level | |
1526 | * dmap control page, depending upon the ag size. examine the ag's | |
1527 | * subtrees for sufficient free space, starting with the leftmost | |
1528 | * subtree. | |
1529 | */ | |
1530 | for (i = 0; i < bmp->db_agwidth; i++, ti++) { | |
1531 | /* is there sufficient free space ? | |
1532 | */ | |
1533 | if (l2nb > dcp->stree[ti]) | |
1534 | continue; | |
1535 | ||
1536 | /* sufficient free space found in a subtree. now search down | |
1537 | * the subtree to find the leftmost leaf that describes this | |
1538 | * free space. | |
1539 | */ | |
1540 | for (k = bmp->db_agheigth; k > 0; k--) { | |
1541 | for (n = 0, m = (ti << 2) + 1; n < 4; n++) { | |
1542 | if (l2nb <= dcp->stree[m + n]) { | |
1543 | ti = m + n; | |
1544 | break; | |
1545 | } | |
1546 | } | |
1547 | if (n == 4) { | |
1548 | jfs_error(bmp->db_ipbmap->i_sb, | |
1549 | "dbAllocAG: failed descending stree"); | |
1550 | release_metapage(mp); | |
1551 | return -EIO; | |
1552 | } | |
1553 | } | |
1554 | ||
1555 | /* determine the block number within the file system | |
1556 | * that corresponds to this leaf. | |
1557 | */ | |
1558 | if (bmp->db_aglevel == 2) | |
1559 | blkno = 0; | |
1560 | else if (bmp->db_aglevel == 1) | |
1561 | blkno &= ~(MAXL1SIZE - 1); | |
1562 | else /* bmp->db_aglevel == 0 */ | |
1563 | blkno &= ~(MAXL0SIZE - 1); | |
1564 | ||
1565 | blkno += | |
1566 | ((s64) (ti - le32_to_cpu(dcp->leafidx))) << budmin; | |
1567 | ||
1568 | /* release the buffer in preparation for going down | |
1569 | * the next level of dmap control pages. | |
1570 | */ | |
1571 | release_metapage(mp); | |
1572 | ||
1573 | /* check if we need to continue to search down the lower | |
1574 | * level dmap control pages. we need to if the number of | |
1575 | * blocks required is less than maximum number of blocks | |
1576 | * described at the next lower level. | |
1577 | */ | |
1578 | if (l2nb < budmin) { | |
1579 | ||
1580 | /* search the lower level dmap control pages to get | |
1581 | * the starting block number of the the dmap that | |
1582 | * contains or starts off the free space. | |
1583 | */ | |
1584 | if ((rc = | |
1585 | dbFindCtl(bmp, l2nb, bmp->db_aglevel - 1, | |
1586 | &blkno))) { | |
1587 | if (rc == -ENOSPC) { | |
1588 | jfs_error(bmp->db_ipbmap->i_sb, | |
1589 | "dbAllocAG: control page " | |
1590 | "inconsistent"); | |
1591 | return -EIO; | |
1592 | } | |
1593 | return (rc); | |
1594 | } | |
1595 | } | |
1596 | ||
1597 | /* allocate the blocks. | |
1598 | */ | |
1599 | rc = dbAllocCtl(bmp, nblocks, l2nb, blkno, results); | |
1600 | if (rc == -ENOSPC) { | |
1601 | jfs_error(bmp->db_ipbmap->i_sb, | |
1602 | "dbAllocAG: unable to allocate blocks"); | |
1603 | rc = -EIO; | |
1604 | } | |
1605 | return (rc); | |
1606 | } | |
1607 | ||
1608 | /* no space in the allocation group. release the buffer and | |
1609 | * return -ENOSPC. | |
1610 | */ | |
1611 | release_metapage(mp); | |
1612 | ||
1613 | return -ENOSPC; | |
1614 | } | |
1615 | ||
1616 | ||
1617 | /* | |
1618 | * NAME: dbAllocAny() | |
1619 | * | |
1620 | * FUNCTION: attempt to allocate the specified number of contiguous | |
1621 | * free blocks anywhere in the file system. | |
1622 | * | |
1623 | * dbAllocAny() attempts to find the sufficient free space by | |
1624 | * searching down the dmap control pages, starting with the | |
1625 | * highest level (i.e. L0, L1, L2) control page. if free space | |
1626 | * large enough to satisfy the desired free space is found, the | |
1627 | * desired free space is allocated. | |
1628 | * | |
1629 | * PARAMETERS: | |
1630 | * bmp - pointer to bmap descriptor | |
1631 | * nblocks - actual number of contiguous free blocks desired. | |
1632 | * l2nb - log2 number of contiguous free blocks desired. | |
1633 | * results - on successful return, set to the starting block number | |
1634 | * of the newly allocated range. | |
1635 | * | |
1636 | * RETURN VALUES: | |
1637 | * 0 - success | |
1638 | * -ENOSPC - insufficient disk resources | |
1639 | * -EIO - i/o error | |
1640 | * | |
1641 | * serialization: IWRITE_LOCK(ipbmap) held on entry/exit; | |
1642 | */ | |
1643 | static int dbAllocAny(struct bmap * bmp, s64 nblocks, int l2nb, s64 * results) | |
1644 | { | |
1645 | int rc; | |
1646 | s64 blkno = 0; | |
1647 | ||
1648 | /* starting with the top level dmap control page, search | |
1649 | * down the dmap control levels for sufficient free space. | |
1650 | * if free space is found, dbFindCtl() returns the starting | |
1651 | * block number of the dmap that contains or starts off the | |
1652 | * range of free space. | |
1653 | */ | |
1654 | if ((rc = dbFindCtl(bmp, l2nb, bmp->db_maxlevel, &blkno))) | |
1655 | return (rc); | |
1656 | ||
1657 | /* allocate the blocks. | |
1658 | */ | |
1659 | rc = dbAllocCtl(bmp, nblocks, l2nb, blkno, results); | |
1660 | if (rc == -ENOSPC) { | |
1661 | jfs_error(bmp->db_ipbmap->i_sb, | |
1662 | "dbAllocAny: unable to allocate blocks"); | |
1663 | return -EIO; | |
1664 | } | |
1665 | return (rc); | |
1666 | } | |
1667 | ||
1668 | ||
1669 | /* | |
1670 | * NAME: dbFindCtl() | |
1671 | * | |
1672 | * FUNCTION: starting at a specified dmap control page level and block | |
1673 | * number, search down the dmap control levels for a range of | |
1674 | * contiguous free blocks large enough to satisfy an allocation | |
1675 | * request for the specified number of free blocks. | |
1676 | * | |
1677 | * if sufficient contiguous free blocks are found, this routine | |
1678 | * returns the starting block number within a dmap page that | |
1679 | * contains or starts a range of contiqious free blocks that | |
1680 | * is sufficient in size. | |
1681 | * | |
1682 | * PARAMETERS: | |
1683 | * bmp - pointer to bmap descriptor | |
1684 | * level - starting dmap control page level. | |
1685 | * l2nb - log2 number of contiguous free blocks desired. | |
1686 | * *blkno - on entry, starting block number for conducting the search. | |
1687 | * on successful return, the first block within a dmap page | |
1688 | * that contains or starts a range of contiguous free blocks. | |
1689 | * | |
1690 | * RETURN VALUES: | |
1691 | * 0 - success | |
1692 | * -ENOSPC - insufficient disk resources | |
1693 | * -EIO - i/o error | |
1694 | * | |
1695 | * serialization: IWRITE_LOCK(ipbmap) held on entry/exit; | |
1696 | */ | |
1697 | static int dbFindCtl(struct bmap * bmp, int l2nb, int level, s64 * blkno) | |
1698 | { | |
1699 | int rc, leafidx, lev; | |
1700 | s64 b, lblkno; | |
1701 | struct dmapctl *dcp; | |
1702 | int budmin; | |
1703 | struct metapage *mp; | |
1704 | ||
1705 | /* starting at the specified dmap control page level and block | |
1706 | * number, search down the dmap control levels for the starting | |
1707 | * block number of a dmap page that contains or starts off | |
1708 | * sufficient free blocks. | |
1709 | */ | |
1710 | for (lev = level, b = *blkno; lev >= 0; lev--) { | |
1711 | /* get the buffer of the dmap control page for the block | |
1712 | * number and level (i.e. L0, L1, L2). | |
1713 | */ | |
1714 | lblkno = BLKTOCTL(b, bmp->db_l2nbperpage, lev); | |
1715 | mp = read_metapage(bmp->db_ipbmap, lblkno, PSIZE, 0); | |
1716 | if (mp == NULL) | |
1717 | return -EIO; | |
1718 | dcp = (struct dmapctl *) mp->data; | |
1719 | budmin = dcp->budmin; | |
1720 | ||
1721 | if (dcp->leafidx != cpu_to_le32(CTLLEAFIND)) { | |
1722 | jfs_error(bmp->db_ipbmap->i_sb, | |
1723 | "dbFindCtl: Corrupt dmapctl page"); | |
1724 | release_metapage(mp); | |
1725 | return -EIO; | |
1726 | } | |
1727 | ||
1728 | /* search the tree within the dmap control page for | |
1729 | * sufficent free space. if sufficient free space is found, | |
1730 | * dbFindLeaf() returns the index of the leaf at which | |
1731 | * free space was found. | |
1732 | */ | |
1733 | rc = dbFindLeaf((dmtree_t *) dcp, l2nb, &leafidx); | |
1734 | ||
1735 | /* release the buffer. | |
1736 | */ | |
1737 | release_metapage(mp); | |
1738 | ||
1739 | /* space found ? | |
1740 | */ | |
1741 | if (rc) { | |
1742 | if (lev != level) { | |
1743 | jfs_error(bmp->db_ipbmap->i_sb, | |
1744 | "dbFindCtl: dmap inconsistent"); | |
1745 | return -EIO; | |
1746 | } | |
1747 | return -ENOSPC; | |
1748 | } | |
1749 | ||
1750 | /* adjust the block number to reflect the location within | |
1751 | * the dmap control page (i.e. the leaf) at which free | |
1752 | * space was found. | |
1753 | */ | |
1754 | b += (((s64) leafidx) << budmin); | |
1755 | ||
1756 | /* we stop the search at this dmap control page level if | |
1757 | * the number of blocks required is greater than or equal | |
1758 | * to the maximum number of blocks described at the next | |
1759 | * (lower) level. | |
1760 | */ | |
1761 | if (l2nb >= budmin) | |
1762 | break; | |
1763 | } | |
1764 | ||
1765 | *blkno = b; | |
1766 | return (0); | |
1767 | } | |
1768 | ||
1769 | ||
1770 | /* | |
1771 | * NAME: dbAllocCtl() | |
1772 | * | |
1773 | * FUNCTION: attempt to allocate a specified number of contiguous | |
1774 | * blocks starting within a specific dmap. | |
1775 | * | |
1776 | * this routine is called by higher level routines that search | |
1777 | * the dmap control pages above the actual dmaps for contiguous | |
1778 | * free space. the result of successful searches by these | |
1779 | * routines are the starting block numbers within dmaps, with | |
1780 | * the dmaps themselves containing the desired contiguous free | |
1781 | * space or starting a contiguous free space of desired size | |
1782 | * that is made up of the blocks of one or more dmaps. these | |
1783 | * calls should not fail due to insufficent resources. | |
1784 | * | |
1785 | * this routine is called in some cases where it is not known | |
1786 | * whether it will fail due to insufficient resources. more | |
1787 | * specifically, this occurs when allocating from an allocation | |
1788 | * group whose size is equal to the number of blocks per dmap. | |
1789 | * in this case, the dmap control pages are not examined prior | |
1790 | * to calling this routine (to save pathlength) and the call | |
1791 | * might fail. | |
1792 | * | |
1793 | * for a request size that fits within a dmap, this routine relies | |
1794 | * upon the dmap's dmtree to find the requested contiguous free | |
1795 | * space. for request sizes that are larger than a dmap, the | |
1796 | * requested free space will start at the first block of the | |
1797 | * first dmap (i.e. blkno). | |
1798 | * | |
1799 | * PARAMETERS: | |
1800 | * bmp - pointer to bmap descriptor | |
1801 | * nblocks - actual number of contiguous free blocks to allocate. | |
1802 | * l2nb - log2 number of contiguous free blocks to allocate. | |
1803 | * blkno - starting block number of the dmap to start the allocation | |
1804 | * from. | |
1805 | * results - on successful return, set to the starting block number | |
1806 | * of the newly allocated range. | |
1807 | * | |
1808 | * RETURN VALUES: | |
1809 | * 0 - success | |
1810 | * -ENOSPC - insufficient disk resources | |
1811 | * -EIO - i/o error | |
1812 | * | |
1813 | * serialization: IWRITE_LOCK(ipbmap) held on entry/exit; | |
1814 | */ | |
1815 | static int | |
1816 | dbAllocCtl(struct bmap * bmp, s64 nblocks, int l2nb, s64 blkno, s64 * results) | |
1817 | { | |
1818 | int rc, nb; | |
1819 | s64 b, lblkno, n; | |
1820 | struct metapage *mp; | |
1821 | struct dmap *dp; | |
1822 | ||
1823 | /* check if the allocation request is confined to a single dmap. | |
1824 | */ | |
1825 | if (l2nb <= L2BPERDMAP) { | |
1826 | /* get the buffer for the dmap. | |
1827 | */ | |
1828 | lblkno = BLKTODMAP(blkno, bmp->db_l2nbperpage); | |
1829 | mp = read_metapage(bmp->db_ipbmap, lblkno, PSIZE, 0); | |
1830 | if (mp == NULL) | |
1831 | return -EIO; | |
1832 | dp = (struct dmap *) mp->data; | |
1833 | ||
1834 | /* try to allocate the blocks. | |
1835 | */ | |
1836 | rc = dbAllocDmapLev(bmp, dp, (int) nblocks, l2nb, results); | |
1837 | if (rc == 0) | |
1838 | mark_metapage_dirty(mp); | |
1839 | ||
1840 | release_metapage(mp); | |
1841 | ||
1842 | return (rc); | |
1843 | } | |
1844 | ||
1845 | /* allocation request involving multiple dmaps. it must start on | |
1846 | * a dmap boundary. | |
1847 | */ | |
1848 | assert((blkno & (BPERDMAP - 1)) == 0); | |
1849 | ||
1850 | /* allocate the blocks dmap by dmap. | |
1851 | */ | |
1852 | for (n = nblocks, b = blkno; n > 0; n -= nb, b += nb) { | |
1853 | /* get the buffer for the dmap. | |
1854 | */ | |
1855 | lblkno = BLKTODMAP(b, bmp->db_l2nbperpage); | |
1856 | mp = read_metapage(bmp->db_ipbmap, lblkno, PSIZE, 0); | |
1857 | if (mp == NULL) { | |
1858 | rc = -EIO; | |
1859 | goto backout; | |
1860 | } | |
1861 | dp = (struct dmap *) mp->data; | |
1862 | ||
1863 | /* the dmap better be all free. | |
1864 | */ | |
1865 | if (dp->tree.stree[ROOT] != L2BPERDMAP) { | |
1866 | release_metapage(mp); | |
1867 | jfs_error(bmp->db_ipbmap->i_sb, | |
1868 | "dbAllocCtl: the dmap is not all free"); | |
1869 | rc = -EIO; | |
1870 | goto backout; | |
1871 | } | |
1872 | ||
1873 | /* determine how many blocks to allocate from this dmap. | |
1874 | */ | |
1875 | nb = min(n, (s64)BPERDMAP); | |
1876 | ||
1877 | /* allocate the blocks from the dmap. | |
1878 | */ | |
1879 | if ((rc = dbAllocDmap(bmp, dp, b, nb))) { | |
1880 | release_metapage(mp); | |
1881 | goto backout; | |
1882 | } | |
1883 | ||
1884 | /* write the buffer. | |
1885 | */ | |
1886 | write_metapage(mp); | |
1887 | } | |
1888 | ||
1889 | /* set the results (starting block number) and return. | |
1890 | */ | |
1891 | *results = blkno; | |
1892 | return (0); | |
1893 | ||
1894 | /* something failed in handling an allocation request involving | |
1895 | * multiple dmaps. we'll try to clean up by backing out any | |
1896 | * allocation that has already happened for this request. if | |
1897 | * we fail in backing out the allocation, we'll mark the file | |
1898 | * system to indicate that blocks have been leaked. | |
1899 | */ | |
1900 | backout: | |
1901 | ||
1902 | /* try to backout the allocations dmap by dmap. | |
1903 | */ | |
1904 | for (n = nblocks - n, b = blkno; n > 0; | |
1905 | n -= BPERDMAP, b += BPERDMAP) { | |
1906 | /* get the buffer for this dmap. | |
1907 | */ | |
1908 | lblkno = BLKTODMAP(b, bmp->db_l2nbperpage); | |
1909 | mp = read_metapage(bmp->db_ipbmap, lblkno, PSIZE, 0); | |
1910 | if (mp == NULL) { | |
1911 | /* could not back out. mark the file system | |
1912 | * to indicate that we have leaked blocks. | |
1913 | */ | |
1914 | jfs_error(bmp->db_ipbmap->i_sb, | |
1915 | "dbAllocCtl: I/O Error: Block Leakage."); | |
1916 | continue; | |
1917 | } | |
1918 | dp = (struct dmap *) mp->data; | |
1919 | ||
1920 | /* free the blocks is this dmap. | |
1921 | */ | |
1922 | if (dbFreeDmap(bmp, dp, b, BPERDMAP)) { | |
1923 | /* could not back out. mark the file system | |
1924 | * to indicate that we have leaked blocks. | |
1925 | */ | |
1926 | release_metapage(mp); | |
1927 | jfs_error(bmp->db_ipbmap->i_sb, | |
1928 | "dbAllocCtl: Block Leakage."); | |
1929 | continue; | |
1930 | } | |
1931 | ||
1932 | /* write the buffer. | |
1933 | */ | |
1934 | write_metapage(mp); | |
1935 | } | |
1936 | ||
1937 | return (rc); | |
1938 | } | |
1939 | ||
1940 | ||
1941 | /* | |
1942 | * NAME: dbAllocDmapLev() | |
1943 | * | |
1944 | * FUNCTION: attempt to allocate a specified number of contiguous blocks | |
1945 | * from a specified dmap. | |
1946 | * | |
1947 | * this routine checks if the contiguous blocks are available. | |
1948 | * if so, nblocks of blocks are allocated; otherwise, ENOSPC is | |
1949 | * returned. | |
1950 | * | |
1951 | * PARAMETERS: | |
1952 | * mp - pointer to bmap descriptor | |
1953 | * dp - pointer to dmap to attempt to allocate blocks from. | |
1954 | * l2nb - log2 number of contiguous block desired. | |
1955 | * nblocks - actual number of contiguous block desired. | |
1956 | * results - on successful return, set to the starting block number | |
1957 | * of the newly allocated range. | |
1958 | * | |
1959 | * RETURN VALUES: | |
1960 | * 0 - success | |
1961 | * -ENOSPC - insufficient disk resources | |
1962 | * -EIO - i/o error | |
1963 | * | |
1964 | * serialization: IREAD_LOCK(ipbmap), e.g., from dbAlloc(), or | |
1965 | * IWRITE_LOCK(ipbmap), e.g., dbAllocCtl(), held on entry/exit; | |
1966 | */ | |
1967 | static int | |
1968 | dbAllocDmapLev(struct bmap * bmp, | |
1969 | struct dmap * dp, int nblocks, int l2nb, s64 * results) | |
1970 | { | |
1971 | s64 blkno; | |
1972 | int leafidx, rc; | |
1973 | ||
1974 | /* can't be more than a dmaps worth of blocks */ | |
1975 | assert(l2nb <= L2BPERDMAP); | |
1976 | ||
1977 | /* search the tree within the dmap page for sufficient | |
1978 | * free space. if sufficient free space is found, dbFindLeaf() | |
1979 | * returns the index of the leaf at which free space was found. | |
1980 | */ | |
1981 | if (dbFindLeaf((dmtree_t *) & dp->tree, l2nb, &leafidx)) | |
1982 | return -ENOSPC; | |
1983 | ||
1984 | /* determine the block number within the file system corresponding | |
1985 | * to the leaf at which free space was found. | |
1986 | */ | |
1987 | blkno = le64_to_cpu(dp->start) + (leafidx << L2DBWORD); | |
1988 | ||
1989 | /* if not all bits of the dmap word are free, get the starting | |
1990 | * bit number within the dmap word of the required string of free | |
1991 | * bits and adjust the block number with this value. | |
1992 | */ | |
1993 | if (dp->tree.stree[leafidx + LEAFIND] < BUDMIN) | |
1994 | blkno += dbFindBits(le32_to_cpu(dp->wmap[leafidx]), l2nb); | |
1995 | ||
1996 | /* allocate the blocks */ | |
1997 | if ((rc = dbAllocDmap(bmp, dp, blkno, nblocks)) == 0) | |
1998 | *results = blkno; | |
1999 | ||
2000 | return (rc); | |
2001 | } | |
2002 | ||
2003 | ||
2004 | /* | |
2005 | * NAME: dbAllocDmap() | |
2006 | * | |
2007 | * FUNCTION: adjust the disk allocation map to reflect the allocation | |
2008 | * of a specified block range within a dmap. | |
2009 | * | |
2010 | * this routine allocates the specified blocks from the dmap | |
2011 | * through a call to dbAllocBits(). if the allocation of the | |
2012 | * block range causes the maximum string of free blocks within | |
2013 | * the dmap to change (i.e. the value of the root of the dmap's | |
2014 | * dmtree), this routine will cause this change to be reflected | |
2015 | * up through the appropriate levels of the dmap control pages | |
2016 | * by a call to dbAdjCtl() for the L0 dmap control page that | |
2017 | * covers this dmap. | |
2018 | * | |
2019 | * PARAMETERS: | |
2020 | * bmp - pointer to bmap descriptor | |
2021 | * dp - pointer to dmap to allocate the block range from. | |
2022 | * blkno - starting block number of the block to be allocated. | |
2023 | * nblocks - number of blocks to be allocated. | |
2024 | * | |
2025 | * RETURN VALUES: | |
2026 | * 0 - success | |
2027 | * -EIO - i/o error | |
2028 | * | |
2029 | * serialization: IREAD_LOCK(ipbmap) or IWRITE_LOCK(ipbmap) held on entry/exit; | |
2030 | */ | |
2031 | static int dbAllocDmap(struct bmap * bmp, struct dmap * dp, s64 blkno, | |
2032 | int nblocks) | |
2033 | { | |
2034 | s8 oldroot; | |
2035 | int rc; | |
2036 | ||
2037 | /* save the current value of the root (i.e. maximum free string) | |
2038 | * of the dmap tree. | |
2039 | */ | |
2040 | oldroot = dp->tree.stree[ROOT]; | |
2041 | ||
2042 | /* allocate the specified (blocks) bits */ | |
2043 | dbAllocBits(bmp, dp, blkno, nblocks); | |
2044 | ||
2045 | /* if the root has not changed, done. */ | |
2046 | if (dp->tree.stree[ROOT] == oldroot) | |
2047 | return (0); | |
2048 | ||
2049 | /* root changed. bubble the change up to the dmap control pages. | |
2050 | * if the adjustment of the upper level control pages fails, | |
2051 | * backout the bit allocation (thus making everything consistent). | |
2052 | */ | |
2053 | if ((rc = dbAdjCtl(bmp, blkno, dp->tree.stree[ROOT], 1, 0))) | |
2054 | dbFreeBits(bmp, dp, blkno, nblocks); | |
2055 | ||
2056 | return (rc); | |
2057 | } | |
2058 | ||
2059 | ||
2060 | /* | |
2061 | * NAME: dbFreeDmap() | |
2062 | * | |
2063 | * FUNCTION: adjust the disk allocation map to reflect the allocation | |
2064 | * of a specified block range within a dmap. | |
2065 | * | |
2066 | * this routine frees the specified blocks from the dmap through | |
2067 | * a call to dbFreeBits(). if the deallocation of the block range | |
2068 | * causes the maximum string of free blocks within the dmap to | |
2069 | * change (i.e. the value of the root of the dmap's dmtree), this | |
2070 | * routine will cause this change to be reflected up through the | |
2071 | * appropriate levels of the dmap control pages by a call to | |
2072 | * dbAdjCtl() for the L0 dmap control page that covers this dmap. | |
2073 | * | |
2074 | * PARAMETERS: | |
2075 | * bmp - pointer to bmap descriptor | |
2076 | * dp - pointer to dmap to free the block range from. | |
2077 | * blkno - starting block number of the block to be freed. | |
2078 | * nblocks - number of blocks to be freed. | |
2079 | * | |
2080 | * RETURN VALUES: | |
2081 | * 0 - success | |
2082 | * -EIO - i/o error | |
2083 | * | |
2084 | * serialization: IREAD_LOCK(ipbmap) or IWRITE_LOCK(ipbmap) held on entry/exit; | |
2085 | */ | |
2086 | static int dbFreeDmap(struct bmap * bmp, struct dmap * dp, s64 blkno, | |
2087 | int nblocks) | |
2088 | { | |
2089 | s8 oldroot; | |
2090 | int rc, word; | |
2091 | ||
2092 | /* save the current value of the root (i.e. maximum free string) | |
2093 | * of the dmap tree. | |
2094 | */ | |
2095 | oldroot = dp->tree.stree[ROOT]; | |
2096 | ||
2097 | /* free the specified (blocks) bits */ | |
2098 | dbFreeBits(bmp, dp, blkno, nblocks); | |
2099 | ||
2100 | /* if the root has not changed, done. */ | |
2101 | if (dp->tree.stree[ROOT] == oldroot) | |
2102 | return (0); | |
2103 | ||
2104 | /* root changed. bubble the change up to the dmap control pages. | |
2105 | * if the adjustment of the upper level control pages fails, | |
2106 | * backout the deallocation. | |
2107 | */ | |
2108 | if ((rc = dbAdjCtl(bmp, blkno, dp->tree.stree[ROOT], 0, 0))) { | |
2109 | word = (blkno & (BPERDMAP - 1)) >> L2DBWORD; | |
2110 | ||
2111 | /* as part of backing out the deallocation, we will have | |
2112 | * to back split the dmap tree if the deallocation caused | |
2113 | * the freed blocks to become part of a larger binary buddy | |
2114 | * system. | |
2115 | */ | |
2116 | if (dp->tree.stree[word] == NOFREE) | |
2117 | dbBackSplit((dmtree_t *) & dp->tree, word); | |
2118 | ||
2119 | dbAllocBits(bmp, dp, blkno, nblocks); | |
2120 | } | |
2121 | ||
2122 | return (rc); | |
2123 | } | |
2124 | ||
2125 | ||
2126 | /* | |
2127 | * NAME: dbAllocBits() | |
2128 | * | |
2129 | * FUNCTION: allocate a specified block range from a dmap. | |
2130 | * | |
2131 | * this routine updates the dmap to reflect the working | |
2132 | * state allocation of the specified block range. it directly | |
2133 | * updates the bits of the working map and causes the adjustment | |
2134 | * of the binary buddy system described by the dmap's dmtree | |
2135 | * leaves to reflect the bits allocated. it also causes the | |
2136 | * dmap's dmtree, as a whole, to reflect the allocated range. | |
2137 | * | |
2138 | * PARAMETERS: | |
2139 | * bmp - pointer to bmap descriptor | |
2140 | * dp - pointer to dmap to allocate bits from. | |
2141 | * blkno - starting block number of the bits to be allocated. | |
2142 | * nblocks - number of bits to be allocated. | |
2143 | * | |
2144 | * RETURN VALUES: none | |
2145 | * | |
2146 | * serialization: IREAD_LOCK(ipbmap) or IWRITE_LOCK(ipbmap) held on entry/exit; | |
2147 | */ | |
2148 | static void dbAllocBits(struct bmap * bmp, struct dmap * dp, s64 blkno, | |
2149 | int nblocks) | |
2150 | { | |
2151 | int dbitno, word, rembits, nb, nwords, wbitno, nw, agno; | |
2152 | dmtree_t *tp = (dmtree_t *) & dp->tree; | |
2153 | int size; | |
2154 | s8 *leaf; | |
2155 | ||
2156 | /* pick up a pointer to the leaves of the dmap tree */ | |
2157 | leaf = dp->tree.stree + LEAFIND; | |
2158 | ||
2159 | /* determine the bit number and word within the dmap of the | |
2160 | * starting block. | |
2161 | */ | |
2162 | dbitno = blkno & (BPERDMAP - 1); | |
2163 | word = dbitno >> L2DBWORD; | |
2164 | ||
2165 | /* block range better be within the dmap */ | |
2166 | assert(dbitno + nblocks <= BPERDMAP); | |
2167 | ||
2168 | /* allocate the bits of the dmap's words corresponding to the block | |
2169 | * range. not all bits of the first and last words may be contained | |
2170 | * within the block range. if this is the case, we'll work against | |
2171 | * those words (i.e. partial first and/or last) on an individual basis | |
2172 | * (a single pass), allocating the bits of interest by hand and | |
2173 | * updating the leaf corresponding to the dmap word. a single pass | |
2174 | * will be used for all dmap words fully contained within the | |
2175 | * specified range. within this pass, the bits of all fully contained | |
2176 | * dmap words will be marked as free in a single shot and the leaves | |
2177 | * will be updated. a single leaf may describe the free space of | |
2178 | * multiple dmap words, so we may update only a subset of the actual | |
2179 | * leaves corresponding to the dmap words of the block range. | |
2180 | */ | |
2181 | for (rembits = nblocks; rembits > 0; rembits -= nb, dbitno += nb) { | |
2182 | /* determine the bit number within the word and | |
2183 | * the number of bits within the word. | |
2184 | */ | |
2185 | wbitno = dbitno & (DBWORD - 1); | |
2186 | nb = min(rembits, DBWORD - wbitno); | |
2187 | ||
2188 | /* check if only part of a word is to be allocated. | |
2189 | */ | |
2190 | if (nb < DBWORD) { | |
2191 | /* allocate (set to 1) the appropriate bits within | |
2192 | * this dmap word. | |
2193 | */ | |
2194 | dp->wmap[word] |= cpu_to_le32(ONES << (DBWORD - nb) | |
2195 | >> wbitno); | |
2196 | ||
2197 | /* update the leaf for this dmap word. in addition | |
2198 | * to setting the leaf value to the binary buddy max | |
2199 | * of the updated dmap word, dbSplit() will split | |
2200 | * the binary system of the leaves if need be. | |
2201 | */ | |
2202 | dbSplit(tp, word, BUDMIN, | |
2203 | dbMaxBud((u8 *) & dp->wmap[word])); | |
2204 | ||
2205 | word += 1; | |
2206 | } else { | |
2207 | /* one or more dmap words are fully contained | |
2208 | * within the block range. determine how many | |
2209 | * words and allocate (set to 1) the bits of these | |
2210 | * words. | |
2211 | */ | |
2212 | nwords = rembits >> L2DBWORD; | |
2213 | memset(&dp->wmap[word], (int) ONES, nwords * 4); | |
2214 | ||
2215 | /* determine how many bits. | |
2216 | */ | |
2217 | nb = nwords << L2DBWORD; | |
2218 | ||
2219 | /* now update the appropriate leaves to reflect | |
2220 | * the allocated words. | |
2221 | */ | |
2222 | for (; nwords > 0; nwords -= nw) { | |
2223 | if (leaf[word] < BUDMIN) { | |
2224 | jfs_error(bmp->db_ipbmap->i_sb, | |
2225 | "dbAllocBits: leaf page " | |
2226 | "corrupt"); | |
2227 | break; | |
2228 | } | |
2229 | ||
2230 | /* determine what the leaf value should be | |
2231 | * updated to as the minimum of the l2 number | |
2232 | * of bits being allocated and the l2 number | |
2233 | * of bits currently described by this leaf. | |
2234 | */ | |
2235 | size = min((int)leaf[word], NLSTOL2BSZ(nwords)); | |
2236 | ||
2237 | /* update the leaf to reflect the allocation. | |
2238 | * in addition to setting the leaf value to | |
2239 | * NOFREE, dbSplit() will split the binary | |
2240 | * system of the leaves to reflect the current | |
2241 | * allocation (size). | |
2242 | */ | |
2243 | dbSplit(tp, word, size, NOFREE); | |
2244 | ||
2245 | /* get the number of dmap words handled */ | |
2246 | nw = BUDSIZE(size, BUDMIN); | |
2247 | word += nw; | |
2248 | } | |
2249 | } | |
2250 | } | |
2251 | ||
2252 | /* update the free count for this dmap */ | |
2253 | dp->nfree = cpu_to_le32(le32_to_cpu(dp->nfree) - nblocks); | |
2254 | ||
2255 | BMAP_LOCK(bmp); | |
2256 | ||
2257 | /* if this allocation group is completely free, | |
2258 | * update the maximum allocation group number if this allocation | |
2259 | * group is the new max. | |
2260 | */ | |
2261 | agno = blkno >> bmp->db_agl2size; | |
2262 | if (agno > bmp->db_maxag) | |
2263 | bmp->db_maxag = agno; | |
2264 | ||
2265 | /* update the free count for the allocation group and map */ | |
2266 | bmp->db_agfree[agno] -= nblocks; | |
2267 | bmp->db_nfree -= nblocks; | |
2268 | ||
2269 | BMAP_UNLOCK(bmp); | |
2270 | } | |
2271 | ||
2272 | ||
2273 | /* | |
2274 | * NAME: dbFreeBits() | |
2275 | * | |
2276 | * FUNCTION: free a specified block range from a dmap. | |
2277 | * | |
2278 | * this routine updates the dmap to reflect the working | |
2279 | * state allocation of the specified block range. it directly | |
2280 | * updates the bits of the working map and causes the adjustment | |
2281 | * of the binary buddy system described by the dmap's dmtree | |
2282 | * leaves to reflect the bits freed. it also causes the dmap's | |
2283 | * dmtree, as a whole, to reflect the deallocated range. | |
2284 | * | |
2285 | * PARAMETERS: | |
2286 | * bmp - pointer to bmap descriptor | |
2287 | * dp - pointer to dmap to free bits from. | |
2288 | * blkno - starting block number of the bits to be freed. | |
2289 | * nblocks - number of bits to be freed. | |
2290 | * | |
2291 | * RETURN VALUES: none | |
2292 | * | |
2293 | * serialization: IREAD_LOCK(ipbmap) or IWRITE_LOCK(ipbmap) held on entry/exit; | |
2294 | */ | |
2295 | static void dbFreeBits(struct bmap * bmp, struct dmap * dp, s64 blkno, | |
2296 | int nblocks) | |
2297 | { | |
2298 | int dbitno, word, rembits, nb, nwords, wbitno, nw, agno; | |
2299 | dmtree_t *tp = (dmtree_t *) & dp->tree; | |
2300 | int size; | |
2301 | ||
2302 | /* determine the bit number and word within the dmap of the | |
2303 | * starting block. | |
2304 | */ | |
2305 | dbitno = blkno & (BPERDMAP - 1); | |
2306 | word = dbitno >> L2DBWORD; | |
2307 | ||
2308 | /* block range better be within the dmap. | |
2309 | */ | |
2310 | assert(dbitno + nblocks <= BPERDMAP); | |
2311 | ||
2312 | /* free the bits of the dmaps words corresponding to the block range. | |
2313 | * not all bits of the first and last words may be contained within | |
2314 | * the block range. if this is the case, we'll work against those | |
2315 | * words (i.e. partial first and/or last) on an individual basis | |
2316 | * (a single pass), freeing the bits of interest by hand and updating | |
2317 | * the leaf corresponding to the dmap word. a single pass will be used | |
2318 | * for all dmap words fully contained within the specified range. | |
2319 | * within this pass, the bits of all fully contained dmap words will | |
2320 | * be marked as free in a single shot and the leaves will be updated. a | |
2321 | * single leaf may describe the free space of multiple dmap words, | |
2322 | * so we may update only a subset of the actual leaves corresponding | |
2323 | * to the dmap words of the block range. | |
2324 | * | |
2325 | * dbJoin() is used to update leaf values and will join the binary | |
2326 | * buddy system of the leaves if the new leaf values indicate this | |
2327 | * should be done. | |
2328 | */ | |
2329 | for (rembits = nblocks; rembits > 0; rembits -= nb, dbitno += nb) { | |
2330 | /* determine the bit number within the word and | |
2331 | * the number of bits within the word. | |
2332 | */ | |
2333 | wbitno = dbitno & (DBWORD - 1); | |
2334 | nb = min(rembits, DBWORD - wbitno); | |
2335 | ||
2336 | /* check if only part of a word is to be freed. | |
2337 | */ | |
2338 | if (nb < DBWORD) { | |
2339 | /* free (zero) the appropriate bits within this | |
2340 | * dmap word. | |
2341 | */ | |
2342 | dp->wmap[word] &= | |
2343 | cpu_to_le32(~(ONES << (DBWORD - nb) | |
2344 | >> wbitno)); | |
2345 | ||
2346 | /* update the leaf for this dmap word. | |
2347 | */ | |
2348 | dbJoin(tp, word, | |
2349 | dbMaxBud((u8 *) & dp->wmap[word])); | |
2350 | ||
2351 | word += 1; | |
2352 | } else { | |
2353 | /* one or more dmap words are fully contained | |
2354 | * within the block range. determine how many | |
2355 | * words and free (zero) the bits of these words. | |
2356 | */ | |
2357 | nwords = rembits >> L2DBWORD; | |
2358 | memset(&dp->wmap[word], 0, nwords * 4); | |
2359 | ||
2360 | /* determine how many bits. | |
2361 | */ | |
2362 | nb = nwords << L2DBWORD; | |
2363 | ||
2364 | /* now update the appropriate leaves to reflect | |
2365 | * the freed words. | |
2366 | */ | |
2367 | for (; nwords > 0; nwords -= nw) { | |
2368 | /* determine what the leaf value should be | |
2369 | * updated to as the minimum of the l2 number | |
2370 | * of bits being freed and the l2 (max) number | |
2371 | * of bits that can be described by this leaf. | |
2372 | */ | |
2373 | size = | |
2374 | min(LITOL2BSZ | |
2375 | (word, L2LPERDMAP, BUDMIN), | |
2376 | NLSTOL2BSZ(nwords)); | |
2377 | ||
2378 | /* update the leaf. | |
2379 | */ | |
2380 | dbJoin(tp, word, size); | |
2381 | ||
2382 | /* get the number of dmap words handled. | |
2383 | */ | |
2384 | nw = BUDSIZE(size, BUDMIN); | |
2385 | word += nw; | |
2386 | } | |
2387 | } | |
2388 | } | |
2389 | ||
2390 | /* update the free count for this dmap. | |
2391 | */ | |
2392 | dp->nfree = cpu_to_le32(le32_to_cpu(dp->nfree) + nblocks); | |
2393 | ||
2394 | BMAP_LOCK(bmp); | |
2395 | ||
2396 | /* update the free count for the allocation group and | |
2397 | * map. | |
2398 | */ | |
2399 | agno = blkno >> bmp->db_agl2size; | |
2400 | bmp->db_nfree += nblocks; | |
2401 | bmp->db_agfree[agno] += nblocks; | |
2402 | ||
2403 | /* check if this allocation group is not completely free and | |
2404 | * if it is currently the maximum (rightmost) allocation group. | |
2405 | * if so, establish the new maximum allocation group number by | |
2406 | * searching left for the first allocation group with allocation. | |
2407 | */ | |
2408 | if ((bmp->db_agfree[agno] == bmp->db_agsize && agno == bmp->db_maxag) || | |
2409 | (agno == bmp->db_numag - 1 && | |
2410 | bmp->db_agfree[agno] == (bmp-> db_mapsize & (BPERDMAP - 1)))) { | |
2411 | while (bmp->db_maxag > 0) { | |
2412 | bmp->db_maxag -= 1; | |
2413 | if (bmp->db_agfree[bmp->db_maxag] != | |
2414 | bmp->db_agsize) | |
2415 | break; | |
2416 | } | |
2417 | ||
2418 | /* re-establish the allocation group preference if the | |
2419 | * current preference is right of the maximum allocation | |
2420 | * group. | |
2421 | */ | |
2422 | if (bmp->db_agpref > bmp->db_maxag) | |
2423 | bmp->db_agpref = bmp->db_maxag; | |
2424 | } | |
2425 | ||
2426 | BMAP_UNLOCK(bmp); | |
2427 | } | |
2428 | ||
2429 | ||
2430 | /* | |
2431 | * NAME: dbAdjCtl() | |
2432 | * | |
2433 | * FUNCTION: adjust a dmap control page at a specified level to reflect | |
2434 | * the change in a lower level dmap or dmap control page's | |
2435 | * maximum string of free blocks (i.e. a change in the root | |
2436 | * of the lower level object's dmtree) due to the allocation | |
2437 | * or deallocation of a range of blocks with a single dmap. | |
2438 | * | |
2439 | * on entry, this routine is provided with the new value of | |
2440 | * the lower level dmap or dmap control page root and the | |
2441 | * starting block number of the block range whose allocation | |
2442 | * or deallocation resulted in the root change. this range | |
2443 | * is respresented by a single leaf of the current dmapctl | |
2444 | * and the leaf will be updated with this value, possibly | |
2445 | * causing a binary buddy system within the leaves to be | |
2446 | * split or joined. the update may also cause the dmapctl's | |
2447 | * dmtree to be updated. | |
2448 | * | |
2449 | * if the adjustment of the dmap control page, itself, causes its | |
2450 | * root to change, this change will be bubbled up to the next dmap | |
2451 | * control level by a recursive call to this routine, specifying | |
2452 | * the new root value and the next dmap control page level to | |
2453 | * be adjusted. | |
2454 | * PARAMETERS: | |
2455 | * bmp - pointer to bmap descriptor | |
2456 | * blkno - the first block of a block range within a dmap. it is | |
2457 | * the allocation or deallocation of this block range that | |
2458 | * requires the dmap control page to be adjusted. | |
2459 | * newval - the new value of the lower level dmap or dmap control | |
2460 | * page root. | |
2461 | * alloc - TRUE if adjustment is due to an allocation. | |
2462 | * level - current level of dmap control page (i.e. L0, L1, L2) to | |
2463 | * be adjusted. | |
2464 | * | |
2465 | * RETURN VALUES: | |
2466 | * 0 - success | |
2467 | * -EIO - i/o error | |
2468 | * | |
2469 | * serialization: IREAD_LOCK(ipbmap) or IWRITE_LOCK(ipbmap) held on entry/exit; | |
2470 | */ | |
2471 | static int | |
2472 | dbAdjCtl(struct bmap * bmp, s64 blkno, int newval, int alloc, int level) | |
2473 | { | |
2474 | struct metapage *mp; | |
2475 | s8 oldroot; | |
2476 | int oldval; | |
2477 | s64 lblkno; | |
2478 | struct dmapctl *dcp; | |
2479 | int rc, leafno, ti; | |
2480 | ||
2481 | /* get the buffer for the dmap control page for the specified | |
2482 | * block number and control page level. | |
2483 | */ | |
2484 | lblkno = BLKTOCTL(blkno, bmp->db_l2nbperpage, level); | |
2485 | mp = read_metapage(bmp->db_ipbmap, lblkno, PSIZE, 0); | |
2486 | if (mp == NULL) | |
2487 | return -EIO; | |
2488 | dcp = (struct dmapctl *) mp->data; | |
2489 | ||
2490 | if (dcp->leafidx != cpu_to_le32(CTLLEAFIND)) { | |
2491 | jfs_error(bmp->db_ipbmap->i_sb, | |
2492 | "dbAdjCtl: Corrupt dmapctl page"); | |
2493 | release_metapage(mp); | |
2494 | return -EIO; | |
2495 | } | |
2496 | ||
2497 | /* determine the leaf number corresponding to the block and | |
2498 | * the index within the dmap control tree. | |
2499 | */ | |
2500 | leafno = BLKTOCTLLEAF(blkno, dcp->budmin); | |
2501 | ti = leafno + le32_to_cpu(dcp->leafidx); | |
2502 | ||
2503 | /* save the current leaf value and the current root level (i.e. | |
2504 | * maximum l2 free string described by this dmapctl). | |
2505 | */ | |
2506 | oldval = dcp->stree[ti]; | |
2507 | oldroot = dcp->stree[ROOT]; | |
2508 | ||
2509 | /* check if this is a control page update for an allocation. | |
2510 | * if so, update the leaf to reflect the new leaf value using | |
2511 | * dbSplit(); otherwise (deallocation), use dbJoin() to udpate | |
2512 | * the leaf with the new value. in addition to updating the | |
2513 | * leaf, dbSplit() will also split the binary buddy system of | |
2514 | * the leaves, if required, and bubble new values within the | |
2515 | * dmapctl tree, if required. similarly, dbJoin() will join | |
2516 | * the binary buddy system of leaves and bubble new values up | |
2517 | * the dmapctl tree as required by the new leaf value. | |
2518 | */ | |
2519 | if (alloc) { | |
2520 | /* check if we are in the middle of a binary buddy | |
2521 | * system. this happens when we are performing the | |
2522 | * first allocation out of an allocation group that | |
2523 | * is part (not the first part) of a larger binary | |
2524 | * buddy system. if we are in the middle, back split | |
2525 | * the system prior to calling dbSplit() which assumes | |
2526 | * that it is at the front of a binary buddy system. | |
2527 | */ | |
2528 | if (oldval == NOFREE) { | |
2529 | dbBackSplit((dmtree_t *) dcp, leafno); | |
2530 | oldval = dcp->stree[ti]; | |
2531 | } | |
2532 | dbSplit((dmtree_t *) dcp, leafno, dcp->budmin, newval); | |
2533 | } else { | |
2534 | dbJoin((dmtree_t *) dcp, leafno, newval); | |
2535 | } | |
2536 | ||
2537 | /* check if the root of the current dmap control page changed due | |
2538 | * to the update and if the current dmap control page is not at | |
2539 | * the current top level (i.e. L0, L1, L2) of the map. if so (i.e. | |
2540 | * root changed and this is not the top level), call this routine | |
2541 | * again (recursion) for the next higher level of the mapping to | |
2542 | * reflect the change in root for the current dmap control page. | |
2543 | */ | |
2544 | if (dcp->stree[ROOT] != oldroot) { | |
2545 | /* are we below the top level of the map. if so, | |
2546 | * bubble the root up to the next higher level. | |
2547 | */ | |
2548 | if (level < bmp->db_maxlevel) { | |
2549 | /* bubble up the new root of this dmap control page to | |
2550 | * the next level. | |
2551 | */ | |
2552 | if ((rc = | |
2553 | dbAdjCtl(bmp, blkno, dcp->stree[ROOT], alloc, | |
2554 | level + 1))) { | |
2555 | /* something went wrong in bubbling up the new | |
2556 | * root value, so backout the changes to the | |
2557 | * current dmap control page. | |
2558 | */ | |
2559 | if (alloc) { | |
2560 | dbJoin((dmtree_t *) dcp, leafno, | |
2561 | oldval); | |
2562 | } else { | |
2563 | /* the dbJoin() above might have | |
2564 | * caused a larger binary buddy system | |
2565 | * to form and we may now be in the | |
2566 | * middle of it. if this is the case, | |
2567 | * back split the buddies. | |
2568 | */ | |
2569 | if (dcp->stree[ti] == NOFREE) | |
2570 | dbBackSplit((dmtree_t *) | |
2571 | dcp, leafno); | |
2572 | dbSplit((dmtree_t *) dcp, leafno, | |
2573 | dcp->budmin, oldval); | |
2574 | } | |
2575 | ||
2576 | /* release the buffer and return the error. | |
2577 | */ | |
2578 | release_metapage(mp); | |
2579 | return (rc); | |
2580 | } | |
2581 | } else { | |
2582 | /* we're at the top level of the map. update | |
2583 | * the bmap control page to reflect the size | |
2584 | * of the maximum free buddy system. | |
2585 | */ | |
2586 | assert(level == bmp->db_maxlevel); | |
2587 | if (bmp->db_maxfreebud != oldroot) { | |
2588 | jfs_error(bmp->db_ipbmap->i_sb, | |
2589 | "dbAdjCtl: the maximum free buddy is " | |
2590 | "not the old root"); | |
2591 | } | |
2592 | bmp->db_maxfreebud = dcp->stree[ROOT]; | |
2593 | } | |
2594 | } | |
2595 | ||
2596 | /* write the buffer. | |
2597 | */ | |
2598 | write_metapage(mp); | |
2599 | ||
2600 | return (0); | |
2601 | } | |
2602 | ||
2603 | ||
2604 | /* | |
2605 | * NAME: dbSplit() | |
2606 | * | |
2607 | * FUNCTION: update the leaf of a dmtree with a new value, splitting | |
2608 | * the leaf from the binary buddy system of the dmtree's | |
2609 | * leaves, as required. | |
2610 | * | |
2611 | * PARAMETERS: | |
2612 | * tp - pointer to the tree containing the leaf. | |
2613 | * leafno - the number of the leaf to be updated. | |
2614 | * splitsz - the size the binary buddy system starting at the leaf | |
2615 | * must be split to, specified as the log2 number of blocks. | |
2616 | * newval - the new value for the leaf. | |
2617 | * | |
2618 | * RETURN VALUES: none | |
2619 | * | |
2620 | * serialization: IREAD_LOCK(ipbmap) or IWRITE_LOCK(ipbmap) held on entry/exit; | |
2621 | */ | |
2622 | static void dbSplit(dmtree_t * tp, int leafno, int splitsz, int newval) | |
2623 | { | |
2624 | int budsz; | |
2625 | int cursz; | |
2626 | s8 *leaf = tp->dmt_stree + le32_to_cpu(tp->dmt_leafidx); | |
2627 | ||
2628 | /* check if the leaf needs to be split. | |
2629 | */ | |
2630 | if (leaf[leafno] > tp->dmt_budmin) { | |
2631 | /* the split occurs by cutting the buddy system in half | |
2632 | * at the specified leaf until we reach the specified | |
2633 | * size. pick up the starting split size (current size | |
2634 | * - 1 in l2) and the corresponding buddy size. | |
2635 | */ | |
2636 | cursz = leaf[leafno] - 1; | |
2637 | budsz = BUDSIZE(cursz, tp->dmt_budmin); | |
2638 | ||
2639 | /* split until we reach the specified size. | |
2640 | */ | |
2641 | while (cursz >= splitsz) { | |
2642 | /* update the buddy's leaf with its new value. | |
2643 | */ | |
2644 | dbAdjTree(tp, leafno ^ budsz, cursz); | |
2645 | ||
2646 | /* on to the next size and buddy. | |
2647 | */ | |
2648 | cursz -= 1; | |
2649 | budsz >>= 1; | |
2650 | } | |
2651 | } | |
2652 | ||
2653 | /* adjust the dmap tree to reflect the specified leaf's new | |
2654 | * value. | |
2655 | */ | |
2656 | dbAdjTree(tp, leafno, newval); | |
2657 | } | |
2658 | ||
2659 | ||
2660 | /* | |
2661 | * NAME: dbBackSplit() | |
2662 | * | |
2663 | * FUNCTION: back split the binary buddy system of dmtree leaves | |
2664 | * that hold a specified leaf until the specified leaf | |
2665 | * starts its own binary buddy system. | |
2666 | * | |
2667 | * the allocators typically perform allocations at the start | |
2668 | * of binary buddy systems and dbSplit() is used to accomplish | |
2669 | * any required splits. in some cases, however, allocation | |
2670 | * may occur in the middle of a binary system and requires a | |
2671 | * back split, with the split proceeding out from the middle of | |
2672 | * the system (less efficient) rather than the start of the | |
2673 | * system (more efficient). the cases in which a back split | |
2674 | * is required are rare and are limited to the first allocation | |
2675 | * within an allocation group which is a part (not first part) | |
2676 | * of a larger binary buddy system and a few exception cases | |
2677 | * in which a previous join operation must be backed out. | |
2678 | * | |
2679 | * PARAMETERS: | |
2680 | * tp - pointer to the tree containing the leaf. | |
2681 | * leafno - the number of the leaf to be updated. | |
2682 | * | |
2683 | * RETURN VALUES: none | |
2684 | * | |
2685 | * serialization: IREAD_LOCK(ipbmap) or IWRITE_LOCK(ipbmap) held on entry/exit; | |
2686 | */ | |
2687 | static void dbBackSplit(dmtree_t * tp, int leafno) | |
2688 | { | |
2689 | int budsz, bud, w, bsz, size; | |
2690 | int cursz; | |
2691 | s8 *leaf = tp->dmt_stree + le32_to_cpu(tp->dmt_leafidx); | |
2692 | ||
2693 | /* leaf should be part (not first part) of a binary | |
2694 | * buddy system. | |
2695 | */ | |
2696 | assert(leaf[leafno] == NOFREE); | |
2697 | ||
2698 | /* the back split is accomplished by iteratively finding the leaf | |
2699 | * that starts the buddy system that contains the specified leaf and | |
2700 | * splitting that system in two. this iteration continues until | |
2701 | * the specified leaf becomes the start of a buddy system. | |
2702 | * | |
2703 | * determine maximum possible l2 size for the specified leaf. | |
2704 | */ | |
2705 | size = | |
2706 | LITOL2BSZ(leafno, le32_to_cpu(tp->dmt_l2nleafs), | |
2707 | tp->dmt_budmin); | |
2708 | ||
2709 | /* determine the number of leaves covered by this size. this | |
2710 | * is the buddy size that we will start with as we search for | |
2711 | * the buddy system that contains the specified leaf. | |
2712 | */ | |
2713 | budsz = BUDSIZE(size, tp->dmt_budmin); | |
2714 | ||
2715 | /* back split. | |
2716 | */ | |
2717 | while (leaf[leafno] == NOFREE) { | |
2718 | /* find the leftmost buddy leaf. | |
2719 | */ | |
2720 | for (w = leafno, bsz = budsz;; bsz <<= 1, | |
2721 | w = (w < bud) ? w : bud) { | |
2722 | assert(bsz < le32_to_cpu(tp->dmt_nleafs)); | |
2723 | ||
2724 | /* determine the buddy. | |
2725 | */ | |
2726 | bud = w ^ bsz; | |
2727 | ||
2728 | /* check if this buddy is the start of the system. | |
2729 | */ | |
2730 | if (leaf[bud] != NOFREE) { | |
2731 | /* split the leaf at the start of the | |
2732 | * system in two. | |
2733 | */ | |
2734 | cursz = leaf[bud] - 1; | |
2735 | dbSplit(tp, bud, cursz, cursz); | |
2736 | break; | |
2737 | } | |
2738 | } | |
2739 | } | |
2740 | ||
2741 | assert(leaf[leafno] == size); | |
2742 | } | |
2743 | ||
2744 | ||
2745 | /* | |
2746 | * NAME: dbJoin() | |
2747 | * | |
2748 | * FUNCTION: update the leaf of a dmtree with a new value, joining | |
2749 | * the leaf with other leaves of the dmtree into a multi-leaf | |
2750 | * binary buddy system, as required. | |
2751 | * | |
2752 | * PARAMETERS: | |
2753 | * tp - pointer to the tree containing the leaf. | |
2754 | * leafno - the number of the leaf to be updated. | |
2755 | * newval - the new value for the leaf. | |
2756 | * | |
2757 | * RETURN VALUES: none | |
2758 | */ | |
2759 | static void dbJoin(dmtree_t * tp, int leafno, int newval) | |
2760 | { | |
2761 | int budsz, buddy; | |
2762 | s8 *leaf; | |
2763 | ||
2764 | /* can the new leaf value require a join with other leaves ? | |
2765 | */ | |
2766 | if (newval >= tp->dmt_budmin) { | |
2767 | /* pickup a pointer to the leaves of the tree. | |
2768 | */ | |
2769 | leaf = tp->dmt_stree + le32_to_cpu(tp->dmt_leafidx); | |
2770 | ||
2771 | /* try to join the specified leaf into a large binary | |
2772 | * buddy system. the join proceeds by attempting to join | |
2773 | * the specified leafno with its buddy (leaf) at new value. | |
2774 | * if the join occurs, we attempt to join the left leaf | |
2775 | * of the joined buddies with its buddy at new value + 1. | |
2776 | * we continue to join until we find a buddy that cannot be | |
2777 | * joined (does not have a value equal to the size of the | |
2778 | * last join) or until all leaves have been joined into a | |
2779 | * single system. | |
2780 | * | |
2781 | * get the buddy size (number of words covered) of | |
2782 | * the new value. | |
2783 | */ | |
2784 | budsz = BUDSIZE(newval, tp->dmt_budmin); | |
2785 | ||
2786 | /* try to join. | |
2787 | */ | |
2788 | while (budsz < le32_to_cpu(tp->dmt_nleafs)) { | |
2789 | /* get the buddy leaf. | |
2790 | */ | |
2791 | buddy = leafno ^ budsz; | |
2792 | ||
2793 | /* if the leaf's new value is greater than its | |
2794 | * buddy's value, we join no more. | |
2795 | */ | |
2796 | if (newval > leaf[buddy]) | |
2797 | break; | |
2798 | ||
2799 | assert(newval == leaf[buddy]); | |
2800 | ||
2801 | /* check which (leafno or buddy) is the left buddy. | |
2802 | * the left buddy gets to claim the blocks resulting | |
2803 | * from the join while the right gets to claim none. | |
2804 | * the left buddy is also eligable to participate in | |
2805 | * a join at the next higher level while the right | |
2806 | * is not. | |
2807 | * | |
2808 | */ | |
2809 | if (leafno < buddy) { | |
2810 | /* leafno is the left buddy. | |
2811 | */ | |
2812 | dbAdjTree(tp, buddy, NOFREE); | |
2813 | } else { | |
2814 | /* buddy is the left buddy and becomes | |
2815 | * leafno. | |
2816 | */ | |
2817 | dbAdjTree(tp, leafno, NOFREE); | |
2818 | leafno = buddy; | |
2819 | } | |
2820 | ||
2821 | /* on to try the next join. | |
2822 | */ | |
2823 | newval += 1; | |
2824 | budsz <<= 1; | |
2825 | } | |
2826 | } | |
2827 | ||
2828 | /* update the leaf value. | |
2829 | */ | |
2830 | dbAdjTree(tp, leafno, newval); | |
2831 | } | |
2832 | ||
2833 | ||
2834 | /* | |
2835 | * NAME: dbAdjTree() | |
2836 | * | |
2837 | * FUNCTION: update a leaf of a dmtree with a new value, adjusting | |
2838 | * the dmtree, as required, to reflect the new leaf value. | |
2839 | * the combination of any buddies must already be done before | |
2840 | * this is called. | |
2841 | * | |
2842 | * PARAMETERS: | |
2843 | * tp - pointer to the tree to be adjusted. | |
2844 | * leafno - the number of the leaf to be updated. | |
2845 | * newval - the new value for the leaf. | |
2846 | * | |
2847 | * RETURN VALUES: none | |
2848 | */ | |
2849 | static void dbAdjTree(dmtree_t * tp, int leafno, int newval) | |
2850 | { | |
2851 | int lp, pp, k; | |
2852 | int max; | |
2853 | ||
2854 | /* pick up the index of the leaf for this leafno. | |
2855 | */ | |
2856 | lp = leafno + le32_to_cpu(tp->dmt_leafidx); | |
2857 | ||
2858 | /* is the current value the same as the old value ? if so, | |
2859 | * there is nothing to do. | |
2860 | */ | |
2861 | if (tp->dmt_stree[lp] == newval) | |
2862 | return; | |
2863 | ||
2864 | /* set the new value. | |
2865 | */ | |
2866 | tp->dmt_stree[lp] = newval; | |
2867 | ||
2868 | /* bubble the new value up the tree as required. | |
2869 | */ | |
2870 | for (k = 0; k < le32_to_cpu(tp->dmt_height); k++) { | |
2871 | /* get the index of the first leaf of the 4 leaf | |
2872 | * group containing the specified leaf (leafno). | |
2873 | */ | |
2874 | lp = ((lp - 1) & ~0x03) + 1; | |
2875 | ||
2876 | /* get the index of the parent of this 4 leaf group. | |
2877 | */ | |
2878 | pp = (lp - 1) >> 2; | |
2879 | ||
2880 | /* determine the maximum of the 4 leaves. | |
2881 | */ | |
2882 | max = TREEMAX(&tp->dmt_stree[lp]); | |
2883 | ||
2884 | /* if the maximum of the 4 is the same as the | |
2885 | * parent's value, we're done. | |
2886 | */ | |
2887 | if (tp->dmt_stree[pp] == max) | |
2888 | break; | |
2889 | ||
2890 | /* parent gets new value. | |
2891 | */ | |
2892 | tp->dmt_stree[pp] = max; | |
2893 | ||
2894 | /* parent becomes leaf for next go-round. | |
2895 | */ | |
2896 | lp = pp; | |
2897 | } | |
2898 | } | |
2899 | ||
2900 | ||
2901 | /* | |
2902 | * NAME: dbFindLeaf() | |
2903 | * | |
2904 | * FUNCTION: search a dmtree_t for sufficient free blocks, returning | |
2905 | * the index of a leaf describing the free blocks if | |
2906 | * sufficient free blocks are found. | |
2907 | * | |
2908 | * the search starts at the top of the dmtree_t tree and | |
2909 | * proceeds down the tree to the leftmost leaf with sufficient | |
2910 | * free space. | |
2911 | * | |
2912 | * PARAMETERS: | |
2913 | * tp - pointer to the tree to be searched. | |
2914 | * l2nb - log2 number of free blocks to search for. | |
2915 | * leafidx - return pointer to be set to the index of the leaf | |
2916 | * describing at least l2nb free blocks if sufficient | |
2917 | * free blocks are found. | |
2918 | * | |
2919 | * RETURN VALUES: | |
2920 | * 0 - success | |
2921 | * -ENOSPC - insufficient free blocks. | |
2922 | */ | |
2923 | static int dbFindLeaf(dmtree_t * tp, int l2nb, int *leafidx) | |
2924 | { | |
2925 | int ti, n = 0, k, x = 0; | |
2926 | ||
2927 | /* first check the root of the tree to see if there is | |
2928 | * sufficient free space. | |
2929 | */ | |
2930 | if (l2nb > tp->dmt_stree[ROOT]) | |
2931 | return -ENOSPC; | |
2932 | ||
2933 | /* sufficient free space available. now search down the tree | |
2934 | * starting at the next level for the leftmost leaf that | |
2935 | * describes sufficient free space. | |
2936 | */ | |
2937 | for (k = le32_to_cpu(tp->dmt_height), ti = 1; | |
2938 | k > 0; k--, ti = ((ti + n) << 2) + 1) { | |
2939 | /* search the four nodes at this level, starting from | |
2940 | * the left. | |
2941 | */ | |
2942 | for (x = ti, n = 0; n < 4; n++) { | |
2943 | /* sufficient free space found. move to the next | |
2944 | * level (or quit if this is the last level). | |
2945 | */ | |
2946 | if (l2nb <= tp->dmt_stree[x + n]) | |
2947 | break; | |
2948 | } | |
2949 | ||
2950 | /* better have found something since the higher | |
2951 | * levels of the tree said it was here. | |
2952 | */ | |
2953 | assert(n < 4); | |
2954 | } | |
2955 | ||
2956 | /* set the return to the leftmost leaf describing sufficient | |
2957 | * free space. | |
2958 | */ | |
2959 | *leafidx = x + n - le32_to_cpu(tp->dmt_leafidx); | |
2960 | ||
2961 | return (0); | |
2962 | } | |
2963 | ||
2964 | ||
2965 | /* | |
2966 | * NAME: dbFindBits() | |
2967 | * | |
2968 | * FUNCTION: find a specified number of binary buddy free bits within a | |
2969 | * dmap bitmap word value. | |
2970 | * | |
2971 | * this routine searches the bitmap value for (1 << l2nb) free | |
2972 | * bits at (1 << l2nb) alignments within the value. | |
2973 | * | |
2974 | * PARAMETERS: | |
2975 | * word - dmap bitmap word value. | |
2976 | * l2nb - number of free bits specified as a log2 number. | |
2977 | * | |
2978 | * RETURN VALUES: | |
2979 | * starting bit number of free bits. | |
2980 | */ | |
2981 | static int dbFindBits(u32 word, int l2nb) | |
2982 | { | |
2983 | int bitno, nb; | |
2984 | u32 mask; | |
2985 | ||
2986 | /* get the number of bits. | |
2987 | */ | |
2988 | nb = 1 << l2nb; | |
2989 | assert(nb <= DBWORD); | |
2990 | ||
2991 | /* complement the word so we can use a mask (i.e. 0s represent | |
2992 | * free bits) and compute the mask. | |
2993 | */ | |
2994 | word = ~word; | |
2995 | mask = ONES << (DBWORD - nb); | |
2996 | ||
2997 | /* scan the word for nb free bits at nb alignments. | |
2998 | */ | |
2999 | for (bitno = 0; mask != 0; bitno += nb, mask >>= nb) { | |
3000 | if ((mask & word) == mask) | |
3001 | break; | |
3002 | } | |
3003 | ||
3004 | ASSERT(bitno < 32); | |
3005 | ||
3006 | /* return the bit number. | |
3007 | */ | |
3008 | return (bitno); | |
3009 | } | |
3010 | ||
3011 | ||
3012 | /* | |
3013 | * NAME: dbMaxBud(u8 *cp) | |
3014 | * | |
3015 | * FUNCTION: determine the largest binary buddy string of free | |
3016 | * bits within 32-bits of the map. | |
3017 | * | |
3018 | * PARAMETERS: | |
3019 | * cp - pointer to the 32-bit value. | |
3020 | * | |
3021 | * RETURN VALUES: | |
3022 | * largest binary buddy of free bits within a dmap word. | |
3023 | */ | |
3024 | static int dbMaxBud(u8 * cp) | |
3025 | { | |
3026 | signed char tmp1, tmp2; | |
3027 | ||
3028 | /* check if the wmap word is all free. if so, the | |
3029 | * free buddy size is BUDMIN. | |
3030 | */ | |
3031 | if (*((uint *) cp) == 0) | |
3032 | return (BUDMIN); | |
3033 | ||
3034 | /* check if the wmap word is half free. if so, the | |
3035 | * free buddy size is BUDMIN-1. | |
3036 | */ | |
3037 | if (*((u16 *) cp) == 0 || *((u16 *) cp + 1) == 0) | |
3038 | return (BUDMIN - 1); | |
3039 | ||
3040 | /* not all free or half free. determine the free buddy | |
3041 | * size thru table lookup using quarters of the wmap word. | |
3042 | */ | |
3043 | tmp1 = max(budtab[cp[2]], budtab[cp[3]]); | |
3044 | tmp2 = max(budtab[cp[0]], budtab[cp[1]]); | |
3045 | return (max(tmp1, tmp2)); | |
3046 | } | |
3047 | ||
3048 | ||
3049 | /* | |
3050 | * NAME: cnttz(uint word) | |
3051 | * | |
3052 | * FUNCTION: determine the number of trailing zeros within a 32-bit | |
3053 | * value. | |
3054 | * | |
3055 | * PARAMETERS: | |
3056 | * value - 32-bit value to be examined. | |
3057 | * | |
3058 | * RETURN VALUES: | |
3059 | * count of trailing zeros | |
3060 | */ | |
3061 | static int cnttz(u32 word) | |
3062 | { | |
3063 | int n; | |
3064 | ||
3065 | for (n = 0; n < 32; n++, word >>= 1) { | |
3066 | if (word & 0x01) | |
3067 | break; | |
3068 | } | |
3069 | ||
3070 | return (n); | |
3071 | } | |
3072 | ||
3073 | ||
3074 | /* | |
3075 | * NAME: cntlz(u32 value) | |
3076 | * | |
3077 | * FUNCTION: determine the number of leading zeros within a 32-bit | |
3078 | * value. | |
3079 | * | |
3080 | * PARAMETERS: | |
3081 | * value - 32-bit value to be examined. | |
3082 | * | |
3083 | * RETURN VALUES: | |
3084 | * count of leading zeros | |
3085 | */ | |
3086 | static int cntlz(u32 value) | |
3087 | { | |
3088 | int n; | |
3089 | ||
3090 | for (n = 0; n < 32; n++, value <<= 1) { | |
3091 | if (value & HIGHORDER) | |
3092 | break; | |
3093 | } | |
3094 | return (n); | |
3095 | } | |
3096 | ||
3097 | ||
3098 | /* | |
3099 | * NAME: blkstol2(s64 nb) | |
3100 | * | |
3101 | * FUNCTION: convert a block count to its log2 value. if the block | |
3102 | * count is not a l2 multiple, it is rounded up to the next | |
3103 | * larger l2 multiple. | |
3104 | * | |
3105 | * PARAMETERS: | |
3106 | * nb - number of blocks | |
3107 | * | |
3108 | * RETURN VALUES: | |
3109 | * log2 number of blocks | |
3110 | */ | |
3111 | int blkstol2(s64 nb) | |
3112 | { | |
3113 | int l2nb; | |
3114 | s64 mask; /* meant to be signed */ | |
3115 | ||
3116 | mask = (s64) 1 << (64 - 1); | |
3117 | ||
3118 | /* count the leading bits. | |
3119 | */ | |
3120 | for (l2nb = 0; l2nb < 64; l2nb++, mask >>= 1) { | |
3121 | /* leading bit found. | |
3122 | */ | |
3123 | if (nb & mask) { | |
3124 | /* determine the l2 value. | |
3125 | */ | |
3126 | l2nb = (64 - 1) - l2nb; | |
3127 | ||
3128 | /* check if we need to round up. | |
3129 | */ | |
3130 | if (~mask & nb) | |
3131 | l2nb++; | |
3132 | ||
3133 | return (l2nb); | |
3134 | } | |
3135 | } | |
3136 | assert(0); | |
3137 | return 0; /* fix compiler warning */ | |
3138 | } | |
3139 | ||
3140 | ||
3141 | /* | |
3142 | * NAME: dbAllocBottomUp() | |
3143 | * | |
3144 | * FUNCTION: alloc the specified block range from the working block | |
3145 | * allocation map. | |
3146 | * | |
3147 | * the blocks will be alloc from the working map one dmap | |
3148 | * at a time. | |
3149 | * | |
3150 | * PARAMETERS: | |
3151 | * ip - pointer to in-core inode; | |
3152 | * blkno - starting block number to be freed. | |
3153 | * nblocks - number of blocks to be freed. | |
3154 | * | |
3155 | * RETURN VALUES: | |
3156 | * 0 - success | |
3157 | * -EIO - i/o error | |
3158 | */ | |
3159 | int dbAllocBottomUp(struct inode *ip, s64 blkno, s64 nblocks) | |
3160 | { | |
3161 | struct metapage *mp; | |
3162 | struct dmap *dp; | |
3163 | int nb, rc; | |
3164 | s64 lblkno, rem; | |
3165 | struct inode *ipbmap = JFS_SBI(ip->i_sb)->ipbmap; | |
3166 | struct bmap *bmp = JFS_SBI(ip->i_sb)->bmap; | |
3167 | ||
3168 | IREAD_LOCK(ipbmap); | |
3169 | ||
3170 | /* block to be allocated better be within the mapsize. */ | |
3171 | ASSERT(nblocks <= bmp->db_mapsize - blkno); | |
3172 | ||
3173 | /* | |
3174 | * allocate the blocks a dmap at a time. | |
3175 | */ | |
3176 | mp = NULL; | |
3177 | for (rem = nblocks; rem > 0; rem -= nb, blkno += nb) { | |
3178 | /* release previous dmap if any */ | |
3179 | if (mp) { | |
3180 | write_metapage(mp); | |
3181 | } | |
3182 | ||
3183 | /* get the buffer for the current dmap. */ | |
3184 | lblkno = BLKTODMAP(blkno, bmp->db_l2nbperpage); | |
3185 | mp = read_metapage(ipbmap, lblkno, PSIZE, 0); | |
3186 | if (mp == NULL) { | |
3187 | IREAD_UNLOCK(ipbmap); | |
3188 | return -EIO; | |
3189 | } | |
3190 | dp = (struct dmap *) mp->data; | |
3191 | ||
3192 | /* determine the number of blocks to be allocated from | |
3193 | * this dmap. | |
3194 | */ | |
3195 | nb = min(rem, BPERDMAP - (blkno & (BPERDMAP - 1))); | |
3196 | ||
3197 | DBFREECK(bmp->db_DBmap, bmp->db_mapsize, blkno, nb); | |
3198 | ||
3199 | /* allocate the blocks. */ | |
3200 | if ((rc = dbAllocDmapBU(bmp, dp, blkno, nb))) { | |
3201 | release_metapage(mp); | |
3202 | IREAD_UNLOCK(ipbmap); | |
3203 | return (rc); | |
3204 | } | |
3205 | ||
3206 | DBALLOC(bmp->db_DBmap, bmp->db_mapsize, blkno, nb); | |
3207 | } | |
3208 | ||
3209 | /* write the last buffer. */ | |
3210 | write_metapage(mp); | |
3211 | ||
3212 | IREAD_UNLOCK(ipbmap); | |
3213 | ||
3214 | return (0); | |
3215 | } | |
3216 | ||
3217 | ||
3218 | static int dbAllocDmapBU(struct bmap * bmp, struct dmap * dp, s64 blkno, | |
3219 | int nblocks) | |
3220 | { | |
3221 | int rc; | |
3222 | int dbitno, word, rembits, nb, nwords, wbitno, agno; | |
3223 | s8 oldroot, *leaf; | |
3224 | struct dmaptree *tp = (struct dmaptree *) & dp->tree; | |
3225 | ||
3226 | /* save the current value of the root (i.e. maximum free string) | |
3227 | * of the dmap tree. | |
3228 | */ | |
3229 | oldroot = tp->stree[ROOT]; | |
3230 | ||
3231 | /* pick up a pointer to the leaves of the dmap tree */ | |
3232 | leaf = tp->stree + LEAFIND; | |
3233 | ||
3234 | /* determine the bit number and word within the dmap of the | |
3235 | * starting block. | |
3236 | */ | |
3237 | dbitno = blkno & (BPERDMAP - 1); | |
3238 | word = dbitno >> L2DBWORD; | |
3239 | ||
3240 | /* block range better be within the dmap */ | |
3241 | assert(dbitno + nblocks <= BPERDMAP); | |
3242 | ||
3243 | /* allocate the bits of the dmap's words corresponding to the block | |
3244 | * range. not all bits of the first and last words may be contained | |
3245 | * within the block range. if this is the case, we'll work against | |
3246 | * those words (i.e. partial first and/or last) on an individual basis | |
3247 | * (a single pass), allocating the bits of interest by hand and | |
3248 | * updating the leaf corresponding to the dmap word. a single pass | |
3249 | * will be used for all dmap words fully contained within the | |
3250 | * specified range. within this pass, the bits of all fully contained | |
3251 | * dmap words will be marked as free in a single shot and the leaves | |
3252 | * will be updated. a single leaf may describe the free space of | |
3253 | * multiple dmap words, so we may update only a subset of the actual | |
3254 | * leaves corresponding to the dmap words of the block range. | |
3255 | */ | |
3256 | for (rembits = nblocks; rembits > 0; rembits -= nb, dbitno += nb) { | |
3257 | /* determine the bit number within the word and | |
3258 | * the number of bits within the word. | |
3259 | */ | |
3260 | wbitno = dbitno & (DBWORD - 1); | |
3261 | nb = min(rembits, DBWORD - wbitno); | |
3262 | ||
3263 | /* check if only part of a word is to be allocated. | |
3264 | */ | |
3265 | if (nb < DBWORD) { | |
3266 | /* allocate (set to 1) the appropriate bits within | |
3267 | * this dmap word. | |
3268 | */ | |
3269 | dp->wmap[word] |= cpu_to_le32(ONES << (DBWORD - nb) | |
3270 | >> wbitno); | |
3271 | ||
3272 | word++; | |
3273 | } else { | |
3274 | /* one or more dmap words are fully contained | |
3275 | * within the block range. determine how many | |
3276 | * words and allocate (set to 1) the bits of these | |
3277 | * words. | |
3278 | */ | |
3279 | nwords = rembits >> L2DBWORD; | |
3280 | memset(&dp->wmap[word], (int) ONES, nwords * 4); | |
3281 | ||
3282 | /* determine how many bits */ | |
3283 | nb = nwords << L2DBWORD; | |
3284 | word += nwords; | |
3285 | } | |
3286 | } | |
3287 | ||
3288 | /* update the free count for this dmap */ | |
3289 | dp->nfree = cpu_to_le32(le32_to_cpu(dp->nfree) - nblocks); | |
3290 | ||
3291 | /* reconstruct summary tree */ | |
3292 | dbInitDmapTree(dp); | |
3293 | ||
3294 | BMAP_LOCK(bmp); | |
3295 | ||
3296 | /* if this allocation group is completely free, | |
3297 | * update the highest active allocation group number | |
3298 | * if this allocation group is the new max. | |
3299 | */ | |
3300 | agno = blkno >> bmp->db_agl2size; | |
3301 | if (agno > bmp->db_maxag) | |
3302 | bmp->db_maxag = agno; | |
3303 | ||
3304 | /* update the free count for the allocation group and map */ | |
3305 | bmp->db_agfree[agno] -= nblocks; | |
3306 | bmp->db_nfree -= nblocks; | |
3307 | ||
3308 | BMAP_UNLOCK(bmp); | |
3309 | ||
3310 | /* if the root has not changed, done. */ | |
3311 | if (tp->stree[ROOT] == oldroot) | |
3312 | return (0); | |
3313 | ||
3314 | /* root changed. bubble the change up to the dmap control pages. | |
3315 | * if the adjustment of the upper level control pages fails, | |
3316 | * backout the bit allocation (thus making everything consistent). | |
3317 | */ | |
3318 | if ((rc = dbAdjCtl(bmp, blkno, tp->stree[ROOT], 1, 0))) | |
3319 | dbFreeBits(bmp, dp, blkno, nblocks); | |
3320 | ||
3321 | return (rc); | |
3322 | } | |
3323 | ||
3324 | ||
3325 | /* | |
3326 | * NAME: dbExtendFS() | |
3327 | * | |
3328 | * FUNCTION: extend bmap from blkno for nblocks; | |
3329 | * dbExtendFS() updates bmap ready for dbAllocBottomUp(); | |
3330 | * | |
3331 | * L2 | |
3332 | * | | |
3333 | * L1---------------------------------L1 | |
3334 | * | | | |
3335 | * L0---------L0---------L0 L0---------L0---------L0 | |
3336 | * | | | | | | | |
3337 | * d0,...,dn d0,...,dn d0,...,dn d0,...,dn d0,...,dn d0,.,dm; | |
3338 | * L2L1L0d0,...,dnL0d0,...,dnL0d0,...,dnL1L0d0,...,dnL0d0,...,dnL0d0,..dm | |
3339 | * | |
3340 | * <---old---><----------------------------extend-----------------------> | |
3341 | */ | |
3342 | int dbExtendFS(struct inode *ipbmap, s64 blkno, s64 nblocks) | |
3343 | { | |
3344 | struct jfs_sb_info *sbi = JFS_SBI(ipbmap->i_sb); | |
3345 | int nbperpage = sbi->nbperpage; | |
3346 | int i, i0 = TRUE, j, j0 = TRUE, k, n; | |
3347 | s64 newsize; | |
3348 | s64 p; | |
3349 | struct metapage *mp, *l2mp, *l1mp = NULL, *l0mp = NULL; | |
3350 | struct dmapctl *l2dcp, *l1dcp, *l0dcp; | |
3351 | struct dmap *dp; | |
3352 | s8 *l0leaf, *l1leaf, *l2leaf; | |
3353 | struct bmap *bmp = sbi->bmap; | |
3354 | int agno, l2agsize, oldl2agsize; | |
3355 | s64 ag_rem; | |
3356 | ||
3357 | newsize = blkno + nblocks; | |
3358 | ||
3359 | jfs_info("dbExtendFS: blkno:%Ld nblocks:%Ld newsize:%Ld", | |
3360 | (long long) blkno, (long long) nblocks, (long long) newsize); | |
3361 | ||
3362 | /* | |
3363 | * initialize bmap control page. | |
3364 | * | |
3365 | * all the data in bmap control page should exclude | |
3366 | * the mkfs hidden dmap page. | |
3367 | */ | |
3368 | ||
3369 | /* update mapsize */ | |
3370 | bmp->db_mapsize = newsize; | |
3371 | bmp->db_maxlevel = BMAPSZTOLEV(bmp->db_mapsize); | |
3372 | ||
3373 | /* compute new AG size */ | |
3374 | l2agsize = dbGetL2AGSize(newsize); | |
3375 | oldl2agsize = bmp->db_agl2size; | |
3376 | ||
3377 | bmp->db_agl2size = l2agsize; | |
3378 | bmp->db_agsize = 1 << l2agsize; | |
3379 | ||
3380 | /* compute new number of AG */ | |
3381 | agno = bmp->db_numag; | |
3382 | bmp->db_numag = newsize >> l2agsize; | |
3383 | bmp->db_numag += ((u32) newsize % (u32) bmp->db_agsize) ? 1 : 0; | |
3384 | ||
3385 | /* | |
3386 | * reconfigure db_agfree[] | |
3387 | * from old AG configuration to new AG configuration; | |
3388 | * | |
3389 | * coalesce contiguous k (newAGSize/oldAGSize) AGs; | |
3390 | * i.e., (AGi, ..., AGj) where i = k*n and j = k*(n+1) - 1 to AGn; | |
3391 | * note: new AG size = old AG size * (2**x). | |
3392 | */ | |
3393 | if (l2agsize == oldl2agsize) | |
3394 | goto extend; | |
3395 | k = 1 << (l2agsize - oldl2agsize); | |
3396 | ag_rem = bmp->db_agfree[0]; /* save agfree[0] */ | |
3397 | for (i = 0, n = 0; i < agno; n++) { | |
3398 | bmp->db_agfree[n] = 0; /* init collection point */ | |
3399 | ||
3400 | /* coalesce cotiguous k AGs; */ | |
3401 | for (j = 0; j < k && i < agno; j++, i++) { | |
3402 | /* merge AGi to AGn */ | |
3403 | bmp->db_agfree[n] += bmp->db_agfree[i]; | |
3404 | } | |
3405 | } | |
3406 | bmp->db_agfree[0] += ag_rem; /* restore agfree[0] */ | |
3407 | ||
3408 | for (; n < MAXAG; n++) | |
3409 | bmp->db_agfree[n] = 0; | |
3410 | ||
3411 | /* | |
3412 | * update highest active ag number | |
3413 | */ | |
3414 | ||
3415 | bmp->db_maxag = bmp->db_maxag / k; | |
3416 | ||
3417 | /* | |
3418 | * extend bmap | |
3419 | * | |
3420 | * update bit maps and corresponding level control pages; | |
3421 | * global control page db_nfree, db_agfree[agno], db_maxfreebud; | |
3422 | */ | |
3423 | extend: | |
3424 | /* get L2 page */ | |
3425 | p = BMAPBLKNO + nbperpage; /* L2 page */ | |
3426 | l2mp = read_metapage(ipbmap, p, PSIZE, 0); | |
3427 | if (!l2mp) { | |
3428 | jfs_error(ipbmap->i_sb, "dbExtendFS: L2 page could not be read"); | |
3429 | return -EIO; | |
3430 | } | |
3431 | l2dcp = (struct dmapctl *) l2mp->data; | |
3432 | ||
3433 | /* compute start L1 */ | |
3434 | k = blkno >> L2MAXL1SIZE; | |
3435 | l2leaf = l2dcp->stree + CTLLEAFIND + k; | |
3436 | p = BLKTOL1(blkno, sbi->l2nbperpage); /* L1 page */ | |
3437 | ||
3438 | /* | |
3439 | * extend each L1 in L2 | |
3440 | */ | |
3441 | for (; k < LPERCTL; k++, p += nbperpage) { | |
3442 | /* get L1 page */ | |
3443 | if (j0) { | |
3444 | /* read in L1 page: (blkno & (MAXL1SIZE - 1)) */ | |
3445 | l1mp = read_metapage(ipbmap, p, PSIZE, 0); | |
3446 | if (l1mp == NULL) | |
3447 | goto errout; | |
3448 | l1dcp = (struct dmapctl *) l1mp->data; | |
3449 | ||
3450 | /* compute start L0 */ | |
3451 | j = (blkno & (MAXL1SIZE - 1)) >> L2MAXL0SIZE; | |
3452 | l1leaf = l1dcp->stree + CTLLEAFIND + j; | |
3453 | p = BLKTOL0(blkno, sbi->l2nbperpage); | |
3454 | j0 = FALSE; | |
3455 | } else { | |
3456 | /* assign/init L1 page */ | |
3457 | l1mp = get_metapage(ipbmap, p, PSIZE, 0); | |
3458 | if (l1mp == NULL) | |
3459 | goto errout; | |
3460 | ||
3461 | l1dcp = (struct dmapctl *) l1mp->data; | |
3462 | ||
3463 | /* compute start L0 */ | |
3464 | j = 0; | |
3465 | l1leaf = l1dcp->stree + CTLLEAFIND; | |
3466 | p += nbperpage; /* 1st L0 of L1.k */ | |
3467 | } | |
3468 | ||
3469 | /* | |
3470 | * extend each L0 in L1 | |
3471 | */ | |
3472 | for (; j < LPERCTL; j++) { | |
3473 | /* get L0 page */ | |
3474 | if (i0) { | |
3475 | /* read in L0 page: (blkno & (MAXL0SIZE - 1)) */ | |
3476 | ||
3477 | l0mp = read_metapage(ipbmap, p, PSIZE, 0); | |
3478 | if (l0mp == NULL) | |
3479 | goto errout; | |
3480 | l0dcp = (struct dmapctl *) l0mp->data; | |
3481 | ||
3482 | /* compute start dmap */ | |
3483 | i = (blkno & (MAXL0SIZE - 1)) >> | |
3484 | L2BPERDMAP; | |
3485 | l0leaf = l0dcp->stree + CTLLEAFIND + i; | |
3486 | p = BLKTODMAP(blkno, | |
3487 | sbi->l2nbperpage); | |
3488 | i0 = FALSE; | |
3489 | } else { | |
3490 | /* assign/init L0 page */ | |
3491 | l0mp = get_metapage(ipbmap, p, PSIZE, 0); | |
3492 | if (l0mp == NULL) | |
3493 | goto errout; | |
3494 | ||
3495 | l0dcp = (struct dmapctl *) l0mp->data; | |
3496 | ||
3497 | /* compute start dmap */ | |
3498 | i = 0; | |
3499 | l0leaf = l0dcp->stree + CTLLEAFIND; | |
3500 | p += nbperpage; /* 1st dmap of L0.j */ | |
3501 | } | |
3502 | ||
3503 | /* | |
3504 | * extend each dmap in L0 | |
3505 | */ | |
3506 | for (; i < LPERCTL; i++) { | |
3507 | /* | |
3508 | * reconstruct the dmap page, and | |
3509 | * initialize corresponding parent L0 leaf | |
3510 | */ | |
3511 | if ((n = blkno & (BPERDMAP - 1))) { | |
3512 | /* read in dmap page: */ | |
3513 | mp = read_metapage(ipbmap, p, | |
3514 | PSIZE, 0); | |
3515 | if (mp == NULL) | |
3516 | goto errout; | |
3517 | n = min(nblocks, (s64)BPERDMAP - n); | |
3518 | } else { | |
3519 | /* assign/init dmap page */ | |
3520 | mp = read_metapage(ipbmap, p, | |
3521 | PSIZE, 0); | |
3522 | if (mp == NULL) | |
3523 | goto errout; | |
3524 | ||
3525 | n = min(nblocks, (s64)BPERDMAP); | |
3526 | } | |
3527 | ||
3528 | dp = (struct dmap *) mp->data; | |
3529 | *l0leaf = dbInitDmap(dp, blkno, n); | |
3530 | ||
3531 | bmp->db_nfree += n; | |
3532 | agno = le64_to_cpu(dp->start) >> l2agsize; | |
3533 | bmp->db_agfree[agno] += n; | |
3534 | ||
3535 | write_metapage(mp); | |
3536 | ||
3537 | l0leaf++; | |
3538 | p += nbperpage; | |
3539 | ||
3540 | blkno += n; | |
3541 | nblocks -= n; | |
3542 | if (nblocks == 0) | |
3543 | break; | |
3544 | } /* for each dmap in a L0 */ | |
3545 | ||
3546 | /* | |
3547 | * build current L0 page from its leaves, and | |
3548 | * initialize corresponding parent L1 leaf | |
3549 | */ | |
3550 | *l1leaf = dbInitDmapCtl(l0dcp, 0, ++i); | |
3551 | write_metapage(l0mp); | |
3552 | l0mp = NULL; | |
3553 | ||
3554 | if (nblocks) | |
3555 | l1leaf++; /* continue for next L0 */ | |
3556 | else { | |
3557 | /* more than 1 L0 ? */ | |
3558 | if (j > 0) | |
3559 | break; /* build L1 page */ | |
3560 | else { | |
3561 | /* summarize in global bmap page */ | |
3562 | bmp->db_maxfreebud = *l1leaf; | |
3563 | release_metapage(l1mp); | |
3564 | release_metapage(l2mp); | |
3565 | goto finalize; | |
3566 | } | |
3567 | } | |
3568 | } /* for each L0 in a L1 */ | |
3569 | ||
3570 | /* | |
3571 | * build current L1 page from its leaves, and | |
3572 | * initialize corresponding parent L2 leaf | |
3573 | */ | |
3574 | *l2leaf = dbInitDmapCtl(l1dcp, 1, ++j); | |
3575 | write_metapage(l1mp); | |
3576 | l1mp = NULL; | |
3577 | ||
3578 | if (nblocks) | |
3579 | l2leaf++; /* continue for next L1 */ | |
3580 | else { | |
3581 | /* more than 1 L1 ? */ | |
3582 | if (k > 0) | |
3583 | break; /* build L2 page */ | |
3584 | else { | |
3585 | /* summarize in global bmap page */ | |
3586 | bmp->db_maxfreebud = *l2leaf; | |
3587 | release_metapage(l2mp); | |
3588 | goto finalize; | |
3589 | } | |
3590 | } | |
3591 | } /* for each L1 in a L2 */ | |
3592 | ||
3593 | jfs_error(ipbmap->i_sb, | |
3594 | "dbExtendFS: function has not returned as expected"); | |
3595 | errout: | |
3596 | if (l0mp) | |
3597 | release_metapage(l0mp); | |
3598 | if (l1mp) | |
3599 | release_metapage(l1mp); | |
3600 | release_metapage(l2mp); | |
3601 | return -EIO; | |
3602 | ||
3603 | /* | |
3604 | * finalize bmap control page | |
3605 | */ | |
3606 | finalize: | |
3607 | ||
3608 | return 0; | |
3609 | } | |
3610 | ||
3611 | ||
3612 | /* | |
3613 | * dbFinalizeBmap() | |
3614 | */ | |
3615 | void dbFinalizeBmap(struct inode *ipbmap) | |
3616 | { | |
3617 | struct bmap *bmp = JFS_SBI(ipbmap->i_sb)->bmap; | |
3618 | int actags, inactags, l2nl; | |
3619 | s64 ag_rem, actfree, inactfree, avgfree; | |
3620 | int i, n; | |
3621 | ||
3622 | /* | |
3623 | * finalize bmap control page | |
3624 | */ | |
3625 | //finalize: | |
3626 | /* | |
3627 | * compute db_agpref: preferred ag to allocate from | |
3628 | * (the leftmost ag with average free space in it); | |
3629 | */ | |
3630 | //agpref: | |
3631 | /* get the number of active ags and inacitve ags */ | |
3632 | actags = bmp->db_maxag + 1; | |
3633 | inactags = bmp->db_numag - actags; | |
3634 | ag_rem = bmp->db_mapsize & (bmp->db_agsize - 1); /* ??? */ | |
3635 | ||
3636 | /* determine how many blocks are in the inactive allocation | |
3637 | * groups. in doing this, we must account for the fact that | |
3638 | * the rightmost group might be a partial group (i.e. file | |
3639 | * system size is not a multiple of the group size). | |
3640 | */ | |
3641 | inactfree = (inactags && ag_rem) ? | |
3642 | ((inactags - 1) << bmp->db_agl2size) + ag_rem | |
3643 | : inactags << bmp->db_agl2size; | |
3644 | ||
3645 | /* determine how many free blocks are in the active | |
3646 | * allocation groups plus the average number of free blocks | |
3647 | * within the active ags. | |
3648 | */ | |
3649 | actfree = bmp->db_nfree - inactfree; | |
3650 | avgfree = (u32) actfree / (u32) actags; | |
3651 | ||
3652 | /* if the preferred allocation group has not average free space. | |
3653 | * re-establish the preferred group as the leftmost | |
3654 | * group with average free space. | |
3655 | */ | |
3656 | if (bmp->db_agfree[bmp->db_agpref] < avgfree) { | |
3657 | for (bmp->db_agpref = 0; bmp->db_agpref < actags; | |
3658 | bmp->db_agpref++) { | |
3659 | if (bmp->db_agfree[bmp->db_agpref] >= avgfree) | |
3660 | break; | |
3661 | } | |
3662 | if (bmp->db_agpref >= bmp->db_numag) { | |
3663 | jfs_error(ipbmap->i_sb, | |
3664 | "cannot find ag with average freespace"); | |
3665 | } | |
3666 | } | |
3667 | ||
3668 | /* | |
3669 | * compute db_aglevel, db_agheigth, db_width, db_agstart: | |
3670 | * an ag is covered in aglevel dmapctl summary tree, | |
3671 | * at agheight level height (from leaf) with agwidth number of nodes | |
3672 | * each, which starts at agstart index node of the smmary tree node | |
3673 | * array; | |
3674 | */ | |
3675 | bmp->db_aglevel = BMAPSZTOLEV(bmp->db_agsize); | |
3676 | l2nl = | |
3677 | bmp->db_agl2size - (L2BPERDMAP + bmp->db_aglevel * L2LPERCTL); | |
3678 | bmp->db_agheigth = l2nl >> 1; | |
3679 | bmp->db_agwidth = 1 << (l2nl - (bmp->db_agheigth << 1)); | |
3680 | for (i = 5 - bmp->db_agheigth, bmp->db_agstart = 0, n = 1; i > 0; | |
3681 | i--) { | |
3682 | bmp->db_agstart += n; | |
3683 | n <<= 2; | |
3684 | } | |
3685 | ||
3686 | } | |
3687 | ||
3688 | ||
3689 | /* | |
3690 | * NAME: dbInitDmap()/ujfs_idmap_page() | |
3691 | * | |
3692 | * FUNCTION: initialize working/persistent bitmap of the dmap page | |
3693 | * for the specified number of blocks: | |
3694 | * | |
3695 | * at entry, the bitmaps had been initialized as free (ZEROS); | |
3696 | * The number of blocks will only account for the actually | |
3697 | * existing blocks. Blocks which don't actually exist in | |
3698 | * the aggregate will be marked as allocated (ONES); | |
3699 | * | |
3700 | * PARAMETERS: | |
3701 | * dp - pointer to page of map | |
3702 | * nblocks - number of blocks this page | |
3703 | * | |
3704 | * RETURNS: NONE | |
3705 | */ | |
3706 | static int dbInitDmap(struct dmap * dp, s64 Blkno, int nblocks) | |
3707 | { | |
3708 | int blkno, w, b, r, nw, nb, i; | |
3709 | ||
3710 | /* starting block number within the dmap */ | |
3711 | blkno = Blkno & (BPERDMAP - 1); | |
3712 | ||
3713 | if (blkno == 0) { | |
3714 | dp->nblocks = dp->nfree = cpu_to_le32(nblocks); | |
3715 | dp->start = cpu_to_le64(Blkno); | |
3716 | ||
3717 | if (nblocks == BPERDMAP) { | |
3718 | memset(&dp->wmap[0], 0, LPERDMAP * 4); | |
3719 | memset(&dp->pmap[0], 0, LPERDMAP * 4); | |
3720 | goto initTree; | |
3721 | } | |
3722 | } else { | |
3723 | dp->nblocks = | |
3724 | cpu_to_le32(le32_to_cpu(dp->nblocks) + nblocks); | |
3725 | dp->nfree = cpu_to_le32(le32_to_cpu(dp->nfree) + nblocks); | |
3726 | } | |
3727 | ||
3728 | /* word number containing start block number */ | |
3729 | w = blkno >> L2DBWORD; | |
3730 | ||
3731 | /* | |
3732 | * free the bits corresponding to the block range (ZEROS): | |
3733 | * note: not all bits of the first and last words may be contained | |
3734 | * within the block range. | |
3735 | */ | |
3736 | for (r = nblocks; r > 0; r -= nb, blkno += nb) { | |
3737 | /* number of bits preceding range to be freed in the word */ | |
3738 | b = blkno & (DBWORD - 1); | |
3739 | /* number of bits to free in the word */ | |
3740 | nb = min(r, DBWORD - b); | |
3741 | ||
3742 | /* is partial word to be freed ? */ | |
3743 | if (nb < DBWORD) { | |
3744 | /* free (set to 0) from the bitmap word */ | |
3745 | dp->wmap[w] &= cpu_to_le32(~(ONES << (DBWORD - nb) | |
3746 | >> b)); | |
3747 | dp->pmap[w] &= cpu_to_le32(~(ONES << (DBWORD - nb) | |
3748 | >> b)); | |
3749 | ||
3750 | /* skip the word freed */ | |
3751 | w++; | |
3752 | } else { | |
3753 | /* free (set to 0) contiguous bitmap words */ | |
3754 | nw = r >> L2DBWORD; | |
3755 | memset(&dp->wmap[w], 0, nw * 4); | |
3756 | memset(&dp->pmap[w], 0, nw * 4); | |
3757 | ||
3758 | /* skip the words freed */ | |
3759 | nb = nw << L2DBWORD; | |
3760 | w += nw; | |
3761 | } | |
3762 | } | |
3763 | ||
3764 | /* | |
3765 | * mark bits following the range to be freed (non-existing | |
3766 | * blocks) as allocated (ONES) | |
3767 | */ | |
3768 | ||
3769 | if (blkno == BPERDMAP) | |
3770 | goto initTree; | |
3771 | ||
3772 | /* the first word beyond the end of existing blocks */ | |
3773 | w = blkno >> L2DBWORD; | |
3774 | ||
3775 | /* does nblocks fall on a 32-bit boundary ? */ | |
3776 | b = blkno & (DBWORD - 1); | |
3777 | if (b) { | |
3778 | /* mark a partial word allocated */ | |
3779 | dp->wmap[w] = dp->pmap[w] = cpu_to_le32(ONES >> b); | |
3780 | w++; | |
3781 | } | |
3782 | ||
3783 | /* set the rest of the words in the page to allocated (ONES) */ | |
3784 | for (i = w; i < LPERDMAP; i++) | |
3785 | dp->pmap[i] = dp->wmap[i] = cpu_to_le32(ONES); | |
3786 | ||
3787 | /* | |
3788 | * init tree | |
3789 | */ | |
3790 | initTree: | |
3791 | return (dbInitDmapTree(dp)); | |
3792 | } | |
3793 | ||
3794 | ||
3795 | /* | |
3796 | * NAME: dbInitDmapTree()/ujfs_complete_dmap() | |
3797 | * | |
3798 | * FUNCTION: initialize summary tree of the specified dmap: | |
3799 | * | |
3800 | * at entry, bitmap of the dmap has been initialized; | |
3801 | * | |
3802 | * PARAMETERS: | |
3803 | * dp - dmap to complete | |
3804 | * blkno - starting block number for this dmap | |
3805 | * treemax - will be filled in with max free for this dmap | |
3806 | * | |
3807 | * RETURNS: max free string at the root of the tree | |
3808 | */ | |
3809 | static int dbInitDmapTree(struct dmap * dp) | |
3810 | { | |
3811 | struct dmaptree *tp; | |
3812 | s8 *cp; | |
3813 | int i; | |
3814 | ||
3815 | /* init fixed info of tree */ | |
3816 | tp = &dp->tree; | |
3817 | tp->nleafs = cpu_to_le32(LPERDMAP); | |
3818 | tp->l2nleafs = cpu_to_le32(L2LPERDMAP); | |
3819 | tp->leafidx = cpu_to_le32(LEAFIND); | |
3820 | tp->height = cpu_to_le32(4); | |
3821 | tp->budmin = BUDMIN; | |
3822 | ||
3823 | /* init each leaf from corresponding wmap word: | |
3824 | * note: leaf is set to NOFREE(-1) if all blocks of corresponding | |
3825 | * bitmap word are allocated. | |
3826 | */ | |
3827 | cp = tp->stree + le32_to_cpu(tp->leafidx); | |
3828 | for (i = 0; i < LPERDMAP; i++) | |
3829 | *cp++ = dbMaxBud((u8 *) & dp->wmap[i]); | |
3830 | ||
3831 | /* build the dmap's binary buddy summary tree */ | |
3832 | return (dbInitTree(tp)); | |
3833 | } | |
3834 | ||
3835 | ||
3836 | /* | |
3837 | * NAME: dbInitTree()/ujfs_adjtree() | |
3838 | * | |
3839 | * FUNCTION: initialize binary buddy summary tree of a dmap or dmapctl. | |
3840 | * | |
3841 | * at entry, the leaves of the tree has been initialized | |
3842 | * from corresponding bitmap word or root of summary tree | |
3843 | * of the child control page; | |
3844 | * configure binary buddy system at the leaf level, then | |
3845 | * bubble up the values of the leaf nodes up the tree. | |
3846 | * | |
3847 | * PARAMETERS: | |
3848 | * cp - Pointer to the root of the tree | |
3849 | * l2leaves- Number of leaf nodes as a power of 2 | |
3850 | * l2min - Number of blocks that can be covered by a leaf | |
3851 | * as a power of 2 | |
3852 | * | |
3853 | * RETURNS: max free string at the root of the tree | |
3854 | */ | |
3855 | static int dbInitTree(struct dmaptree * dtp) | |
3856 | { | |
3857 | int l2max, l2free, bsize, nextb, i; | |
3858 | int child, parent, nparent; | |
3859 | s8 *tp, *cp, *cp1; | |
3860 | ||
3861 | tp = dtp->stree; | |
3862 | ||
3863 | /* Determine the maximum free string possible for the leaves */ | |
3864 | l2max = le32_to_cpu(dtp->l2nleafs) + dtp->budmin; | |
3865 | ||
3866 | /* | |
3867 | * configure the leaf levevl into binary buddy system | |
3868 | * | |
3869 | * Try to combine buddies starting with a buddy size of 1 | |
3870 | * (i.e. two leaves). At a buddy size of 1 two buddy leaves | |
3871 | * can be combined if both buddies have a maximum free of l2min; | |
3872 | * the combination will result in the left-most buddy leaf having | |
3873 | * a maximum free of l2min+1. | |
3874 | * After processing all buddies for a given size, process buddies | |
3875 | * at the next higher buddy size (i.e. current size * 2) and | |
3876 | * the next maximum free (current free + 1). | |
3877 | * This continues until the maximum possible buddy combination | |
3878 | * yields maximum free. | |
3879 | */ | |
3880 | for (l2free = dtp->budmin, bsize = 1; l2free < l2max; | |
3881 | l2free++, bsize = nextb) { | |
3882 | /* get next buddy size == current buddy pair size */ | |
3883 | nextb = bsize << 1; | |
3884 | ||
3885 | /* scan each adjacent buddy pair at current buddy size */ | |
3886 | for (i = 0, cp = tp + le32_to_cpu(dtp->leafidx); | |
3887 | i < le32_to_cpu(dtp->nleafs); | |
3888 | i += nextb, cp += nextb) { | |
3889 | /* coalesce if both adjacent buddies are max free */ | |
3890 | if (*cp == l2free && *(cp + bsize) == l2free) { | |
3891 | *cp = l2free + 1; /* left take right */ | |
3892 | *(cp + bsize) = -1; /* right give left */ | |
3893 | } | |
3894 | } | |
3895 | } | |
3896 | ||
3897 | /* | |
3898 | * bubble summary information of leaves up the tree. | |
3899 | * | |
3900 | * Starting at the leaf node level, the four nodes described by | |
3901 | * the higher level parent node are compared for a maximum free and | |
3902 | * this maximum becomes the value of the parent node. | |
3903 | * when all lower level nodes are processed in this fashion then | |
3904 | * move up to the next level (parent becomes a lower level node) and | |
3905 | * continue the process for that level. | |
3906 | */ | |
3907 | for (child = le32_to_cpu(dtp->leafidx), | |
3908 | nparent = le32_to_cpu(dtp->nleafs) >> 2; | |
3909 | nparent > 0; nparent >>= 2, child = parent) { | |
3910 | /* get index of 1st node of parent level */ | |
3911 | parent = (child - 1) >> 2; | |
3912 | ||
3913 | /* set the value of the parent node as the maximum | |
3914 | * of the four nodes of the current level. | |
3915 | */ | |
3916 | for (i = 0, cp = tp + child, cp1 = tp + parent; | |
3917 | i < nparent; i++, cp += 4, cp1++) | |
3918 | *cp1 = TREEMAX(cp); | |
3919 | } | |
3920 | ||
3921 | return (*tp); | |
3922 | } | |
3923 | ||
3924 | ||
3925 | /* | |
3926 | * dbInitDmapCtl() | |
3927 | * | |
3928 | * function: initialize dmapctl page | |
3929 | */ | |
3930 | static int dbInitDmapCtl(struct dmapctl * dcp, int level, int i) | |
3931 | { /* start leaf index not covered by range */ | |
3932 | s8 *cp; | |
3933 | ||
3934 | dcp->nleafs = cpu_to_le32(LPERCTL); | |
3935 | dcp->l2nleafs = cpu_to_le32(L2LPERCTL); | |
3936 | dcp->leafidx = cpu_to_le32(CTLLEAFIND); | |
3937 | dcp->height = cpu_to_le32(5); | |
3938 | dcp->budmin = L2BPERDMAP + L2LPERCTL * level; | |
3939 | ||
3940 | /* | |
3941 | * initialize the leaves of current level that were not covered | |
3942 | * by the specified input block range (i.e. the leaves have no | |
3943 | * low level dmapctl or dmap). | |
3944 | */ | |
3945 | cp = &dcp->stree[CTLLEAFIND + i]; | |
3946 | for (; i < LPERCTL; i++) | |
3947 | *cp++ = NOFREE; | |
3948 | ||
3949 | /* build the dmap's binary buddy summary tree */ | |
3950 | return (dbInitTree((struct dmaptree *) dcp)); | |
3951 | } | |
3952 | ||
3953 | ||
3954 | /* | |
3955 | * NAME: dbGetL2AGSize()/ujfs_getagl2size() | |
3956 | * | |
3957 | * FUNCTION: Determine log2(allocation group size) from aggregate size | |
3958 | * | |
3959 | * PARAMETERS: | |
3960 | * nblocks - Number of blocks in aggregate | |
3961 | * | |
3962 | * RETURNS: log2(allocation group size) in aggregate blocks | |
3963 | */ | |
3964 | static int dbGetL2AGSize(s64 nblocks) | |
3965 | { | |
3966 | s64 sz; | |
3967 | s64 m; | |
3968 | int l2sz; | |
3969 | ||
3970 | if (nblocks < BPERDMAP * MAXAG) | |
3971 | return (L2BPERDMAP); | |
3972 | ||
3973 | /* round up aggregate size to power of 2 */ | |
3974 | m = ((u64) 1 << (64 - 1)); | |
3975 | for (l2sz = 64; l2sz >= 0; l2sz--, m >>= 1) { | |
3976 | if (m & nblocks) | |
3977 | break; | |
3978 | } | |
3979 | ||
3980 | sz = (s64) 1 << l2sz; | |
3981 | if (sz < nblocks) | |
3982 | l2sz += 1; | |
3983 | ||
3984 | /* agsize = roundupSize/max_number_of_ag */ | |
3985 | return (l2sz - L2MAXAG); | |
3986 | } | |
3987 | ||
3988 | ||
3989 | /* | |
3990 | * NAME: dbMapFileSizeToMapSize() | |
3991 | * | |
3992 | * FUNCTION: compute number of blocks the block allocation map file | |
3993 | * can cover from the map file size; | |
3994 | * | |
3995 | * RETURNS: Number of blocks which can be covered by this block map file; | |
3996 | */ | |
3997 | ||
3998 | /* | |
3999 | * maximum number of map pages at each level including control pages | |
4000 | */ | |
4001 | #define MAXL0PAGES (1 + LPERCTL) | |
4002 | #define MAXL1PAGES (1 + LPERCTL * MAXL0PAGES) | |
4003 | #define MAXL2PAGES (1 + LPERCTL * MAXL1PAGES) | |
4004 | ||
4005 | /* | |
4006 | * convert number of map pages to the zero origin top dmapctl level | |
4007 | */ | |
4008 | #define BMAPPGTOLEV(npages) \ | |
4009 | (((npages) <= 3 + MAXL0PAGES) ? 0 \ | |
4010 | : ((npages) <= 2 + MAXL1PAGES) ? 1 : 2) | |
4011 | ||
4012 | s64 dbMapFileSizeToMapSize(struct inode * ipbmap) | |
4013 | { | |
4014 | struct super_block *sb = ipbmap->i_sb; | |
4015 | s64 nblocks; | |
4016 | s64 npages, ndmaps; | |
4017 | int level, i; | |
4018 | int complete, factor; | |
4019 | ||
4020 | nblocks = ipbmap->i_size >> JFS_SBI(sb)->l2bsize; | |
4021 | npages = nblocks >> JFS_SBI(sb)->l2nbperpage; | |
4022 | level = BMAPPGTOLEV(npages); | |
4023 | ||
4024 | /* At each level, accumulate the number of dmap pages covered by | |
4025 | * the number of full child levels below it; | |
4026 | * repeat for the last incomplete child level. | |
4027 | */ | |
4028 | ndmaps = 0; | |
4029 | npages--; /* skip the first global control page */ | |
4030 | /* skip higher level control pages above top level covered by map */ | |
4031 | npages -= (2 - level); | |
4032 | npages--; /* skip top level's control page */ | |
4033 | for (i = level; i >= 0; i--) { | |
4034 | factor = | |
4035 | (i == 2) ? MAXL1PAGES : ((i == 1) ? MAXL0PAGES : 1); | |
4036 | complete = (u32) npages / factor; | |
4037 | ndmaps += complete * ((i == 2) ? LPERCTL * LPERCTL | |
4038 | : ((i == 1) ? LPERCTL : 1)); | |
4039 | ||
4040 | /* pages in last/incomplete child */ | |
4041 | npages = (u32) npages % factor; | |
4042 | /* skip incomplete child's level control page */ | |
4043 | npages--; | |
4044 | } | |
4045 | ||
4046 | /* convert the number of dmaps into the number of blocks | |
4047 | * which can be covered by the dmaps; | |
4048 | */ | |
4049 | nblocks = ndmaps << L2BPERDMAP; | |
4050 | ||
4051 | return (nblocks); | |
4052 | } | |
4053 | ||
4054 | ||
4055 | #ifdef _JFS_DEBUG_DMAP | |
4056 | /* | |
4057 | * DBinitmap() | |
4058 | */ | |
4059 | static void DBinitmap(s64 size, struct inode *ipbmap, u32 ** results) | |
4060 | { | |
4061 | int npages; | |
4062 | u32 *dbmap, *d; | |
4063 | int n; | |
4064 | s64 lblkno, cur_block; | |
4065 | struct dmap *dp; | |
4066 | struct metapage *mp; | |
4067 | ||
4068 | npages = size / 32768; | |
4069 | npages += (size % 32768) ? 1 : 0; | |
4070 | ||
4071 | dbmap = (u32 *) xmalloc(npages * 4096, L2PSIZE, kernel_heap); | |
4072 | if (dbmap == NULL) | |
4073 | BUG(); /* Not robust since this is only unused debug code */ | |
4074 | ||
4075 | for (n = 0, d = dbmap; n < npages; n++, d += 1024) | |
4076 | bzero(d, 4096); | |
4077 | ||
4078 | /* Need to initialize from disk map pages | |
4079 | */ | |
4080 | for (d = dbmap, cur_block = 0; cur_block < size; | |
4081 | cur_block += BPERDMAP, d += LPERDMAP) { | |
4082 | lblkno = BLKTODMAP(cur_block, | |
4083 | JFS_SBI(ipbmap->i_sb)->bmap-> | |
4084 | db_l2nbperpage); | |
4085 | mp = read_metapage(ipbmap, lblkno, PSIZE, 0); | |
4086 | if (mp == NULL) { | |
4087 | jfs_error(ipbmap->i_sb, | |
4088 | "DBinitmap: could not read disk map page"); | |
4089 | continue; | |
4090 | } | |
4091 | dp = (struct dmap *) mp->data; | |
4092 | ||
4093 | for (n = 0; n < LPERDMAP; n++) | |
4094 | d[n] = le32_to_cpu(dp->wmap[n]); | |
4095 | ||
4096 | release_metapage(mp); | |
4097 | } | |
4098 | ||
4099 | *results = dbmap; | |
4100 | } | |
4101 | ||
4102 | ||
4103 | /* | |
4104 | * DBAlloc() | |
4105 | */ | |
4106 | void DBAlloc(uint * dbmap, s64 mapsize, s64 blkno, s64 nblocks) | |
4107 | { | |
4108 | int word, nb, bitno; | |
4109 | u32 mask; | |
4110 | ||
4111 | assert(blkno > 0 && blkno < mapsize); | |
4112 | assert(nblocks > 0 && nblocks <= mapsize); | |
4113 | ||
4114 | assert(blkno + nblocks <= mapsize); | |
4115 | ||
4116 | dbmap += (blkno / 32); | |
4117 | while (nblocks > 0) { | |
4118 | bitno = blkno & (32 - 1); | |
4119 | nb = min(nblocks, 32 - bitno); | |
4120 | ||
4121 | mask = (0xffffffff << (32 - nb) >> bitno); | |
4122 | assert((mask & *dbmap) == 0); | |
4123 | *dbmap |= mask; | |
4124 | ||
4125 | dbmap++; | |
4126 | blkno += nb; | |
4127 | nblocks -= nb; | |
4128 | } | |
4129 | } | |
4130 | ||
4131 | ||
4132 | /* | |
4133 | * DBFree() | |
4134 | */ | |
4135 | static void DBFree(uint * dbmap, s64 mapsize, s64 blkno, s64 nblocks) | |
4136 | { | |
4137 | int word, nb, bitno; | |
4138 | u32 mask; | |
4139 | ||
4140 | assert(blkno > 0 && blkno < mapsize); | |
4141 | assert(nblocks > 0 && nblocks <= mapsize); | |
4142 | ||
4143 | assert(blkno + nblocks <= mapsize); | |
4144 | ||
4145 | dbmap += (blkno / 32); | |
4146 | while (nblocks > 0) { | |
4147 | bitno = blkno & (32 - 1); | |
4148 | nb = min(nblocks, 32 - bitno); | |
4149 | ||
4150 | mask = (0xffffffff << (32 - nb) >> bitno); | |
4151 | assert((mask & *dbmap) == mask); | |
4152 | *dbmap &= ~mask; | |
4153 | ||
4154 | dbmap++; | |
4155 | blkno += nb; | |
4156 | nblocks -= nb; | |
4157 | } | |
4158 | } | |
4159 | ||
4160 | ||
4161 | /* | |
4162 | * DBAllocCK() | |
4163 | */ | |
4164 | static void DBAllocCK(uint * dbmap, s64 mapsize, s64 blkno, s64 nblocks) | |
4165 | { | |
4166 | int word, nb, bitno; | |
4167 | u32 mask; | |
4168 | ||
4169 | assert(blkno > 0 && blkno < mapsize); | |
4170 | assert(nblocks > 0 && nblocks <= mapsize); | |
4171 | ||
4172 | assert(blkno + nblocks <= mapsize); | |
4173 | ||
4174 | dbmap += (blkno / 32); | |
4175 | while (nblocks > 0) { | |
4176 | bitno = blkno & (32 - 1); | |
4177 | nb = min(nblocks, 32 - bitno); | |
4178 | ||
4179 | mask = (0xffffffff << (32 - nb) >> bitno); | |
4180 | assert((mask & *dbmap) == mask); | |
4181 | ||
4182 | dbmap++; | |
4183 | blkno += nb; | |
4184 | nblocks -= nb; | |
4185 | } | |
4186 | } | |
4187 | ||
4188 | ||
4189 | /* | |
4190 | * DBFreeCK() | |
4191 | */ | |
4192 | static void DBFreeCK(uint * dbmap, s64 mapsize, s64 blkno, s64 nblocks) | |
4193 | { | |
4194 | int word, nb, bitno; | |
4195 | u32 mask; | |
4196 | ||
4197 | assert(blkno > 0 && blkno < mapsize); | |
4198 | assert(nblocks > 0 && nblocks <= mapsize); | |
4199 | ||
4200 | assert(blkno + nblocks <= mapsize); | |
4201 | ||
4202 | dbmap += (blkno / 32); | |
4203 | while (nblocks > 0) { | |
4204 | bitno = blkno & (32 - 1); | |
4205 | nb = min(nblocks, 32 - bitno); | |
4206 | ||
4207 | mask = (0xffffffff << (32 - nb) >> bitno); | |
4208 | assert((mask & *dbmap) == 0); | |
4209 | ||
4210 | dbmap++; | |
4211 | blkno += nb; | |
4212 | nblocks -= nb; | |
4213 | } | |
4214 | } | |
4215 | ||
4216 | ||
4217 | /* | |
4218 | * dbPrtMap() | |
4219 | */ | |
4220 | static void dbPrtMap(struct bmap * bmp) | |
4221 | { | |
4222 | printk(" mapsize: %d%d\n", bmp->db_mapsize); | |
4223 | printk(" nfree: %d%d\n", bmp->db_nfree); | |
4224 | printk(" numag: %d\n", bmp->db_numag); | |
4225 | printk(" agsize: %d%d\n", bmp->db_agsize); | |
4226 | printk(" agl2size: %d\n", bmp->db_agl2size); | |
4227 | printk(" agwidth: %d\n", bmp->db_agwidth); | |
4228 | printk(" agstart: %d\n", bmp->db_agstart); | |
4229 | printk(" agheigth: %d\n", bmp->db_agheigth); | |
4230 | printk(" aglevel: %d\n", bmp->db_aglevel); | |
4231 | printk(" maxlevel: %d\n", bmp->db_maxlevel); | |
4232 | printk(" maxag: %d\n", bmp->db_maxag); | |
4233 | printk(" agpref: %d\n", bmp->db_agpref); | |
4234 | printk(" l2nbppg: %d\n", bmp->db_l2nbperpage); | |
4235 | } | |
4236 | ||
4237 | ||
4238 | /* | |
4239 | * dbPrtCtl() | |
4240 | */ | |
4241 | static void dbPrtCtl(struct dmapctl * dcp) | |
4242 | { | |
4243 | int i, j, n; | |
4244 | ||
4245 | printk(" height: %08x\n", le32_to_cpu(dcp->height)); | |
4246 | printk(" leafidx: %08x\n", le32_to_cpu(dcp->leafidx)); | |
4247 | printk(" budmin: %08x\n", dcp->budmin); | |
4248 | printk(" nleafs: %08x\n", le32_to_cpu(dcp->nleafs)); | |
4249 | printk(" l2nleafs: %08x\n", le32_to_cpu(dcp->l2nleafs)); | |
4250 | ||
4251 | printk("\n Tree:\n"); | |
4252 | for (i = 0; i < CTLLEAFIND; i += 8) { | |
4253 | n = min(8, CTLLEAFIND - i); | |
4254 | ||
4255 | for (j = 0; j < n; j++) | |
4256 | printf(" [%03x]: %02x", i + j, | |
4257 | (char) dcp->stree[i + j]); | |
4258 | printf("\n"); | |
4259 | } | |
4260 | ||
4261 | printk("\n Tree Leaves:\n"); | |
4262 | for (i = 0; i < LPERCTL; i += 8) { | |
4263 | n = min(8, LPERCTL - i); | |
4264 | ||
4265 | for (j = 0; j < n; j++) | |
4266 | printf(" [%03x]: %02x", | |
4267 | i + j, | |
4268 | (char) dcp->stree[i + j + CTLLEAFIND]); | |
4269 | printf("\n"); | |
4270 | } | |
4271 | } | |
4272 | #endif /* _JFS_DEBUG_DMAP */ |