xref: /openbmc/linux/fs/jfs/resize.c (revision 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2)
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 <linux/buffer_head.h>
21 #include <linux/quotaops.h>
22 #include "jfs_incore.h"
23 #include "jfs_filsys.h"
24 #include "jfs_metapage.h"
25 #include "jfs_dinode.h"
26 #include "jfs_imap.h"
27 #include "jfs_dmap.h"
28 #include "jfs_superblock.h"
29 #include "jfs_txnmgr.h"
30 #include "jfs_debug.h"
31 
32 #define BITSPERPAGE     (PSIZE << 3)
33 #define L2MEGABYTE      20
34 #define MEGABYTE        (1 << L2MEGABYTE)
35 #define MEGABYTE32     (MEGABYTE << 5)
36 
37 /* convert block number to bmap file page number */
38 #define BLKTODMAPN(b)\
39         (((b) >> 13) + ((b) >> 23) + ((b) >> 33) + 3 + 1)
40 
41 /*
42  *      jfs_extendfs()
43  *
44  * function: extend file system;
45  *
46  *   |-------------------------------|----------|----------|
47  *   file system space               fsck       inline log
48  *                                   workspace  space
49  *
50  * input:
51  *      new LVSize: in LV blocks (required)
52  *      new LogSize: in LV blocks (optional)
53  *      new FSSize: in LV blocks (optional)
54  *
55  * new configuration:
56  * 1. set new LogSize as specified or default from new LVSize;
57  * 2. compute new FSCKSize from new LVSize;
58  * 3. set new FSSize as MIN(FSSize, LVSize-(LogSize+FSCKSize)) where
59  *    assert(new FSSize >= old FSSize),
60  *    i.e., file system must not be shrinked;
61  */
62 int jfs_extendfs(struct super_block *sb, s64 newLVSize, int newLogSize)
63 {
64 	int rc = 0;
65 	struct jfs_sb_info *sbi = JFS_SBI(sb);
66 	struct inode *ipbmap = sbi->ipbmap;
67 	struct inode *ipbmap2;
68 	struct inode *ipimap = sbi->ipimap;
69 	struct jfs_log *log = sbi->log;
70 	struct bmap *bmp = sbi->bmap;
71 	s64 newLogAddress, newFSCKAddress;
72 	int newFSCKSize;
73 	s64 newMapSize = 0, mapSize;
74 	s64 XAddress, XSize, nblocks, xoff, xaddr, t64;
75 	s64 oldLVSize;
76 	s64 newFSSize;
77 	s64 VolumeSize;
78 	int newNpages = 0, nPages, newPage, xlen, t32;
79 	int tid;
80 	int log_formatted = 0;
81 	struct inode *iplist[1];
82 	struct jfs_superblock *j_sb, *j_sb2;
83 	uint old_agsize;
84 	struct buffer_head *bh, *bh2;
85 
86 	/* If the volume hasn't grown, get out now */
87 
88 	if (sbi->mntflag & JFS_INLINELOG)
89 		oldLVSize = addressPXD(&sbi->logpxd) + lengthPXD(&sbi->logpxd);
90 	else
91 		oldLVSize = addressPXD(&sbi->fsckpxd) +
92 		    lengthPXD(&sbi->fsckpxd);
93 
94 	if (oldLVSize >= newLVSize) {
95 		printk(KERN_WARNING
96 		       "jfs_extendfs: volume hasn't grown, returning\n");
97 		goto out;
98 	}
99 
100 	VolumeSize = sb->s_bdev->bd_inode->i_size >> sb->s_blocksize_bits;
101 
102 	if (VolumeSize) {
103 		if (newLVSize > VolumeSize) {
104 			printk(KERN_WARNING "jfs_extendfs: invalid size\n");
105 			rc = -EINVAL;
106 			goto out;
107 		}
108 	} else {
109 		/* check the device */
110 		bh = sb_bread(sb, newLVSize - 1);
111 		if (!bh) {
112 			printk(KERN_WARNING "jfs_extendfs: invalid size\n");
113 			rc = -EINVAL;
114 			goto out;
115 		}
116 		bforget(bh);
117 	}
118 
119 	/* Can't extend write-protected drive */
120 
121 	if (isReadOnly(ipbmap)) {
122 		printk(KERN_WARNING "jfs_extendfs: read-only file system\n");
123 		rc = -EROFS;
124 		goto out;
125 	}
126 
127 	/*
128 	 *      reconfigure LV spaces
129 	 *      ---------------------
130 	 *
131 	 * validate new size, or, if not specified, determine new size
132 	 */
133 
134 	/*
135 	 * reconfigure inline log space:
136 	 */
137 	if ((sbi->mntflag & JFS_INLINELOG)) {
138 		if (newLogSize == 0) {
139 			/*
140 			 * no size specified: default to 1/256 of aggregate
141 			 * size; rounded up to a megabyte boundary;
142 			 */
143 			newLogSize = newLVSize >> 8;
144 			t32 = (1 << (20 - sbi->l2bsize)) - 1;
145 			newLogSize = (newLogSize + t32) & ~t32;
146 			newLogSize =
147 			    min(newLogSize, MEGABYTE32 >> sbi->l2bsize);
148 		} else {
149 			/*
150 			 * convert the newLogSize to fs blocks.
151 			 *
152 			 * Since this is given in megabytes, it will always be
153 			 * an even number of pages.
154 			 */
155 			newLogSize = (newLogSize * MEGABYTE) >> sbi->l2bsize;
156 		}
157 
158 	} else
159 		newLogSize = 0;
160 
161 	newLogAddress = newLVSize - newLogSize;
162 
163 	/*
164 	 * reconfigure fsck work space:
165 	 *
166 	 * configure it to the end of the logical volume regardless of
167 	 * whether file system extends to the end of the aggregate;
168 	 * Need enough 4k pages to cover:
169 	 *  - 1 bit per block in aggregate rounded up to BPERDMAP boundary
170 	 *  - 1 extra page to handle control page and intermediate level pages
171 	 *  - 50 extra pages for the chkdsk service log
172 	 */
173 	t64 = ((newLVSize - newLogSize + BPERDMAP - 1) >> L2BPERDMAP)
174 	    << L2BPERDMAP;
175 	t32 = ((t64 + (BITSPERPAGE - 1)) / BITSPERPAGE) + 1 + 50;
176 	newFSCKSize = t32 << sbi->l2nbperpage;
177 	newFSCKAddress = newLogAddress - newFSCKSize;
178 
179 	/*
180 	 * compute new file system space;
181 	 */
182 	newFSSize = newLVSize - newLogSize - newFSCKSize;
183 
184 	/* file system cannot be shrinked */
185 	if (newFSSize < bmp->db_mapsize) {
186 		rc = -EINVAL;
187 		goto out;
188 	}
189 
190 	/*
191 	 * If we're expanding enough that the inline log does not overlap
192 	 * the old one, we can format the new log before we quiesce the
193 	 * filesystem.
194 	 */
195 	if ((sbi->mntflag & JFS_INLINELOG) && (newLogAddress > oldLVSize)) {
196 		if ((rc = lmLogFormat(log, newLogAddress, newLogSize)))
197 			goto out;
198 		log_formatted = 1;
199 	}
200 	/*
201 	 *      quiesce file system
202 	 *
203 	 * (prepare to move the inline log and to prevent map update)
204 	 *
205 	 * block any new transactions and wait for completion of
206 	 * all wip transactions and flush modified pages s.t.
207 	 * on-disk file system is in consistent state and
208 	 * log is not required for recovery.
209 	 */
210 	txQuiesce(sb);
211 
212 	if (sbi->mntflag & JFS_INLINELOG) {
213 		/*
214 		 * deactivate old inline log
215 		 */
216 		lmLogShutdown(log);
217 
218 		/*
219 		 * mark on-disk super block for fs in transition;
220 		 *
221 		 * update on-disk superblock for the new space configuration
222 		 * of inline log space and fsck work space descriptors:
223 		 * N.B. FS descriptor is NOT updated;
224 		 *
225 		 * crash recovery:
226 		 * logredo(): if FM_EXTENDFS, return to fsck() for cleanup;
227 		 * fsck(): if FM_EXTENDFS, reformat inline log and fsck
228 		 * workspace from superblock inline log descriptor and fsck
229 		 * workspace descriptor;
230 		 */
231 
232 		/* read in superblock */
233 		if ((rc = readSuper(sb, &bh)))
234 			goto error_out;
235 		j_sb = (struct jfs_superblock *)bh->b_data;
236 
237 		/* mark extendfs() in progress */
238 		j_sb->s_state |= cpu_to_le32(FM_EXTENDFS);
239 		j_sb->s_xsize = cpu_to_le64(newFSSize);
240 		PXDaddress(&j_sb->s_xfsckpxd, newFSCKAddress);
241 		PXDlength(&j_sb->s_xfsckpxd, newFSCKSize);
242 		PXDaddress(&j_sb->s_xlogpxd, newLogAddress);
243 		PXDlength(&j_sb->s_xlogpxd, newLogSize);
244 
245 		/* synchronously update superblock */
246 		mark_buffer_dirty(bh);
247 		sync_dirty_buffer(bh);
248 		brelse(bh);
249 
250 		/*
251 		 * format new inline log synchronously;
252 		 *
253 		 * crash recovery: if log move in progress,
254 		 * reformat log and exit success;
255 		 */
256 		if (!log_formatted)
257 			if ((rc = lmLogFormat(log, newLogAddress, newLogSize)))
258 				goto error_out;
259 
260 		/*
261 		 * activate new log
262 		 */
263 		log->base = newLogAddress;
264 		log->size = newLogSize >> (L2LOGPSIZE - sb->s_blocksize_bits);
265 		if ((rc = lmLogInit(log)))
266 			goto error_out;
267 	}
268 
269 	/*
270 	 *      extend block allocation map
271 	 *      ---------------------------
272 	 *
273 	 * extendfs() for new extension, retry after crash recovery;
274 	 *
275 	 * note: both logredo() and fsck() rebuild map from
276 	 * the bitmap and configuration parameter from superblock
277 	 * (disregarding all other control information in the map);
278 	 *
279 	 * superblock:
280 	 *  s_size: aggregate size in physical blocks;
281 	 */
282 	/*
283 	 *      compute the new block allocation map configuration
284 	 *
285 	 * map dinode:
286 	 *  di_size: map file size in byte;
287 	 *  di_nblocks: number of blocks allocated for map file;
288 	 *  di_mapsize: number of blocks in aggregate (covered by map);
289 	 * map control page:
290 	 *  db_mapsize: number of blocks in aggregate (covered by map);
291 	 */
292 	newMapSize = newFSSize;
293 	/* number of data pages of new bmap file:
294 	 * roundup new size to full dmap page boundary and
295 	 * add 1 extra dmap page for next extendfs()
296 	 */
297 	t64 = (newMapSize - 1) + BPERDMAP;
298 	newNpages = BLKTODMAPN(t64) + 1;
299 
300 	/*
301 	 *      extend map from current map (WITHOUT growing mapfile)
302 	 *
303 	 * map new extension with unmapped part of the last partial
304 	 * dmap page, if applicable, and extra page(s) allocated
305 	 * at end of bmap by mkfs() or previous extendfs();
306 	 */
307       extendBmap:
308 	/* compute number of blocks requested to extend */
309 	mapSize = bmp->db_mapsize;
310 	XAddress = mapSize;	/* eXtension Address */
311 	XSize = newMapSize - mapSize;	/* eXtension Size */
312 	old_agsize = bmp->db_agsize;	/* We need to know if this changes */
313 
314 	/* compute number of blocks that can be extended by current mapfile */
315 	t64 = dbMapFileSizeToMapSize(ipbmap);
316 	if (mapSize > t64) {
317 		printk(KERN_ERR "jfs_extendfs: mapSize (0x%Lx) > t64 (0x%Lx)\n",
318 		       (long long) mapSize, (long long) t64);
319 		rc = -EIO;
320 		goto error_out;
321 	}
322 	nblocks = min(t64 - mapSize, XSize);
323 
324 	/*
325 	 * update map pages for new extension:
326 	 *
327 	 * update/init dmap and bubble up the control hierarchy
328 	 * incrementally fold up dmaps into upper levels;
329 	 * update bmap control page;
330 	 */
331 	if ((rc = dbExtendFS(ipbmap, XAddress, nblocks)))
332 		goto error_out;
333 	/*
334 	 * the map now has extended to cover additional nblocks:
335 	 * dn_mapsize = oldMapsize + nblocks;
336 	 */
337 	/* ipbmap->i_mapsize += nblocks; */
338 	XSize -= nblocks;
339 
340 	/*
341 	 *      grow map file to cover remaining extension
342 	 *      and/or one extra dmap page for next extendfs();
343 	 *
344 	 * allocate new map pages and its backing blocks, and
345 	 * update map file xtree
346 	 */
347 	/* compute number of data pages of current bmap file */
348 	nPages = ipbmap->i_size >> L2PSIZE;
349 
350 	/* need to grow map file ? */
351 	if (nPages == newNpages)
352 		goto finalizeBmap;
353 
354 	/*
355 	 * grow bmap file for the new map pages required:
356 	 *
357 	 * allocate growth at the start of newly extended region;
358 	 * bmap file only grows sequentially, i.e., both data pages
359 	 * and possibly xtree index pages may grow in append mode,
360 	 * s.t. logredo() can reconstruct pre-extension state
361 	 * by washing away bmap file of pages outside s_size boundary;
362 	 */
363 	/*
364 	 * journal map file growth as if a regular file growth:
365 	 * (note: bmap is created with di_mode = IFJOURNAL|IFREG);
366 	 *
367 	 * journaling of bmap file growth is not required since
368 	 * logredo() do/can not use log records of bmap file growth
369 	 * but it provides careful write semantics, pmap update, etc.;
370 	 */
371 	/* synchronous write of data pages: bmap data pages are
372 	 * cached in meta-data cache, and not written out
373 	 * by txCommit();
374 	 */
375 	filemap_fdatawait(ipbmap->i_mapping);
376 	filemap_fdatawrite(ipbmap->i_mapping);
377 	filemap_fdatawait(ipbmap->i_mapping);
378 	diWriteSpecial(ipbmap, 0);
379 
380 	newPage = nPages;	/* first new page number */
381 	xoff = newPage << sbi->l2nbperpage;
382 	xlen = (newNpages - nPages) << sbi->l2nbperpage;
383 	xlen = min(xlen, (int) nblocks) & ~(sbi->nbperpage - 1);
384 	xaddr = XAddress;
385 
386 	tid = txBegin(sb, COMMIT_FORCE);
387 
388 	if ((rc = xtAppend(tid, ipbmap, 0, xoff, nblocks, &xlen, &xaddr, 0))) {
389 		txEnd(tid);
390 		goto error_out;
391 	}
392 	/* update bmap file size */
393 	ipbmap->i_size += xlen << sbi->l2bsize;
394 	inode_add_bytes(ipbmap, xlen << sbi->l2bsize);
395 
396 	iplist[0] = ipbmap;
397 	rc = txCommit(tid, 1, &iplist[0], COMMIT_FORCE);
398 
399 	txEnd(tid);
400 
401 	if (rc)
402 		goto error_out;
403 
404 	/*
405 	 * map file has been grown now to cover extension to further out;
406 	 * di_size = new map file size;
407 	 *
408 	 * if huge extension, the previous extension based on previous
409 	 * map file size may not have been sufficient to cover whole extension
410 	 * (it could have been used up for new map pages),
411 	 * but the newly grown map file now covers lot bigger new free space
412 	 * available for further extension of map;
413 	 */
414 	/* any more blocks to extend ? */
415 	if (XSize)
416 		goto extendBmap;
417 
418       finalizeBmap:
419 	/* finalize bmap */
420 	dbFinalizeBmap(ipbmap);
421 
422 	/*
423 	 *      update inode allocation map
424 	 *      ---------------------------
425 	 *
426 	 * move iag lists from old to new iag;
427 	 * agstart field is not updated for logredo() to reconstruct
428 	 * iag lists if system crash occurs.
429 	 * (computation of ag number from agstart based on agsize
430 	 * will correctly identify the new ag);
431 	 */
432 	/* if new AG size the same as old AG size, done! */
433 	if (bmp->db_agsize != old_agsize) {
434 		if ((rc = diExtendFS(ipimap, ipbmap)))
435 			goto error_out;
436 
437 		/* finalize imap */
438 		if ((rc = diSync(ipimap)))
439 			goto error_out;
440 	}
441 
442 	/*
443 	 *      finalize
444 	 *      --------
445 	 *
446 	 * extension is committed when on-disk super block is
447 	 * updated with new descriptors: logredo will recover
448 	 * crash before it to pre-extension state;
449 	 */
450 
451 	/* sync log to skip log replay of bmap file growth transaction; */
452 	/* lmLogSync(log, 1); */
453 
454 	/*
455 	 * synchronous write bmap global control page;
456 	 * for crash before completion of write
457 	 * logredo() will recover to pre-extendfs state;
458 	 * for crash after completion of write,
459 	 * logredo() will recover post-extendfs state;
460 	 */
461 	if ((rc = dbSync(ipbmap)))
462 		goto error_out;
463 
464 	/*
465 	 * copy primary bmap inode to secondary bmap inode
466 	 */
467 
468 	ipbmap2 = diReadSpecial(sb, BMAP_I, 1);
469 	if (ipbmap2 == NULL) {
470 		printk(KERN_ERR "jfs_extendfs: diReadSpecial(bmap) failed\n");
471 		goto error_out;
472 	}
473 	memcpy(&JFS_IP(ipbmap2)->i_xtroot, &JFS_IP(ipbmap)->i_xtroot, 288);
474 	ipbmap2->i_size = ipbmap->i_size;
475 	ipbmap2->i_blocks = ipbmap->i_blocks;
476 
477 	diWriteSpecial(ipbmap2, 1);
478 	diFreeSpecial(ipbmap2);
479 
480 	/*
481 	 *      update superblock
482 	 */
483 	if ((rc = readSuper(sb, &bh)))
484 		goto error_out;
485 	j_sb = (struct jfs_superblock *)bh->b_data;
486 
487 	/* mark extendfs() completion */
488 	j_sb->s_state &= cpu_to_le32(~FM_EXTENDFS);
489 	j_sb->s_size = cpu_to_le64(bmp->db_mapsize <<
490 				   le16_to_cpu(j_sb->s_l2bfactor));
491 	j_sb->s_agsize = cpu_to_le32(bmp->db_agsize);
492 
493 	/* update inline log space descriptor */
494 	if (sbi->mntflag & JFS_INLINELOG) {
495 		PXDaddress(&(j_sb->s_logpxd), newLogAddress);
496 		PXDlength(&(j_sb->s_logpxd), newLogSize);
497 	}
498 
499 	/* record log's mount serial number */
500 	j_sb->s_logserial = cpu_to_le32(log->serial);
501 
502 	/* update fsck work space descriptor */
503 	PXDaddress(&(j_sb->s_fsckpxd), newFSCKAddress);
504 	PXDlength(&(j_sb->s_fsckpxd), newFSCKSize);
505 	j_sb->s_fscklog = 1;
506 	/* sb->s_fsckloglen remains the same */
507 
508 	/* Update secondary superblock */
509 	bh2 = sb_bread(sb, SUPER2_OFF >> sb->s_blocksize_bits);
510 	if (bh2) {
511 		j_sb2 = (struct jfs_superblock *)bh2->b_data;
512 		memcpy(j_sb2, j_sb, sizeof (struct jfs_superblock));
513 
514 		mark_buffer_dirty(bh);
515 		sync_dirty_buffer(bh2);
516 		brelse(bh2);
517 	}
518 
519 	/* write primary superblock */
520 	mark_buffer_dirty(bh);
521 	sync_dirty_buffer(bh);
522 	brelse(bh);
523 
524 	goto resume;
525 
526       error_out:
527 	jfs_error(sb, "jfs_extendfs");
528 
529       resume:
530 	/*
531 	 *      resume file system transactions
532 	 */
533 	txResume(sb);
534 
535       out:
536 	return rc;
537 }
538