xref: /openbmc/linux/fs/jfs/resize.c (revision 95e9fd10)
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 shrunk;
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 	s64 old_agsize;
84 	int agsizechanged = 0;
85 	struct buffer_head *bh, *bh2;
86 
87 	/* If the volume hasn't grown, get out now */
88 
89 	if (sbi->mntflag & JFS_INLINELOG)
90 		oldLVSize = addressPXD(&sbi->logpxd) + lengthPXD(&sbi->logpxd);
91 	else
92 		oldLVSize = addressPXD(&sbi->fsckpxd) +
93 		    lengthPXD(&sbi->fsckpxd);
94 
95 	if (oldLVSize >= newLVSize) {
96 		printk(KERN_WARNING
97 		       "jfs_extendfs: volume hasn't grown, returning\n");
98 		goto out;
99 	}
100 
101 	VolumeSize = sb->s_bdev->bd_inode->i_size >> sb->s_blocksize_bits;
102 
103 	if (VolumeSize) {
104 		if (newLVSize > VolumeSize) {
105 			printk(KERN_WARNING "jfs_extendfs: invalid size\n");
106 			rc = -EINVAL;
107 			goto out;
108 		}
109 	} else {
110 		/* check the device */
111 		bh = sb_bread(sb, newLVSize - 1);
112 		if (!bh) {
113 			printk(KERN_WARNING "jfs_extendfs: invalid size\n");
114 			rc = -EINVAL;
115 			goto out;
116 		}
117 		bforget(bh);
118 	}
119 
120 	/* Can't extend write-protected drive */
121 
122 	if (isReadOnly(ipbmap)) {
123 		printk(KERN_WARNING "jfs_extendfs: read-only file system\n");
124 		rc = -EROFS;
125 		goto out;
126 	}
127 
128 	/*
129 	 *	reconfigure LV spaces
130 	 *	---------------------
131 	 *
132 	 * validate new size, or, if not specified, determine new size
133 	 */
134 
135 	/*
136 	 * reconfigure inline log space:
137 	 */
138 	if ((sbi->mntflag & JFS_INLINELOG)) {
139 		if (newLogSize == 0) {
140 			/*
141 			 * no size specified: default to 1/256 of aggregate
142 			 * size; rounded up to a megabyte boundary;
143 			 */
144 			newLogSize = newLVSize >> 8;
145 			t32 = (1 << (20 - sbi->l2bsize)) - 1;
146 			newLogSize = (newLogSize + t32) & ~t32;
147 			newLogSize =
148 			    min(newLogSize, MEGABYTE32 >> sbi->l2bsize);
149 		} else {
150 			/*
151 			 * convert the newLogSize to fs blocks.
152 			 *
153 			 * Since this is given in megabytes, it will always be
154 			 * an even number of pages.
155 			 */
156 			newLogSize = (newLogSize * MEGABYTE) >> sbi->l2bsize;
157 		}
158 
159 	} else
160 		newLogSize = 0;
161 
162 	newLogAddress = newLVSize - newLogSize;
163 
164 	/*
165 	 * reconfigure fsck work space:
166 	 *
167 	 * configure it to the end of the logical volume regardless of
168 	 * whether file system extends to the end of the aggregate;
169 	 * Need enough 4k pages to cover:
170 	 *  - 1 bit per block in aggregate rounded up to BPERDMAP boundary
171 	 *  - 1 extra page to handle control page and intermediate level pages
172 	 *  - 50 extra pages for the chkdsk service log
173 	 */
174 	t64 = ((newLVSize - newLogSize + BPERDMAP - 1) >> L2BPERDMAP)
175 	    << L2BPERDMAP;
176 	t32 = DIV_ROUND_UP(t64, BITSPERPAGE) + 1 + 50;
177 	newFSCKSize = t32 << sbi->l2nbperpage;
178 	newFSCKAddress = newLogAddress - newFSCKSize;
179 
180 	/*
181 	 * compute new file system space;
182 	 */
183 	newFSSize = newLVSize - newLogSize - newFSCKSize;
184 
185 	/* file system cannot be shrunk */
186 	if (newFSSize < bmp->db_mapsize) {
187 		rc = -EINVAL;
188 		goto out;
189 	}
190 
191 	/*
192 	 * If we're expanding enough that the inline log does not overlap
193 	 * the old one, we can format the new log before we quiesce the
194 	 * filesystem.
195 	 */
196 	if ((sbi->mntflag & JFS_INLINELOG) && (newLogAddress > oldLVSize)) {
197 		if ((rc = lmLogFormat(log, newLogAddress, newLogSize)))
198 			goto out;
199 		log_formatted = 1;
200 	}
201 	/*
202 	 *	quiesce file system
203 	 *
204 	 * (prepare to move the inline log and to prevent map update)
205 	 *
206 	 * block any new transactions and wait for completion of
207 	 * all wip transactions and flush modified pages s.t.
208 	 * on-disk file system is in consistent state and
209 	 * log is not required for recovery.
210 	 */
211 	txQuiesce(sb);
212 
213 	/* Reset size of direct inode */
214 	sbi->direct_inode->i_size =  sb->s_bdev->bd_inode->i_size;
215 
216 	if (sbi->mntflag & JFS_INLINELOG) {
217 		/*
218 		 * deactivate old inline log
219 		 */
220 		lmLogShutdown(log);
221 
222 		/*
223 		 * mark on-disk super block for fs in transition;
224 		 *
225 		 * update on-disk superblock for the new space configuration
226 		 * of inline log space and fsck work space descriptors:
227 		 * N.B. FS descriptor is NOT updated;
228 		 *
229 		 * crash recovery:
230 		 * logredo(): if FM_EXTENDFS, return to fsck() for cleanup;
231 		 * fsck(): if FM_EXTENDFS, reformat inline log and fsck
232 		 * workspace from superblock inline log descriptor and fsck
233 		 * workspace descriptor;
234 		 */
235 
236 		/* read in superblock */
237 		if ((rc = readSuper(sb, &bh)))
238 			goto error_out;
239 		j_sb = (struct jfs_superblock *)bh->b_data;
240 
241 		/* mark extendfs() in progress */
242 		j_sb->s_state |= cpu_to_le32(FM_EXTENDFS);
243 		j_sb->s_xsize = cpu_to_le64(newFSSize);
244 		PXDaddress(&j_sb->s_xfsckpxd, newFSCKAddress);
245 		PXDlength(&j_sb->s_xfsckpxd, newFSCKSize);
246 		PXDaddress(&j_sb->s_xlogpxd, newLogAddress);
247 		PXDlength(&j_sb->s_xlogpxd, newLogSize);
248 
249 		/* synchronously update superblock */
250 		mark_buffer_dirty(bh);
251 		sync_dirty_buffer(bh);
252 		brelse(bh);
253 
254 		/*
255 		 * format new inline log synchronously;
256 		 *
257 		 * crash recovery: if log move in progress,
258 		 * reformat log and exit success;
259 		 */
260 		if (!log_formatted)
261 			if ((rc = lmLogFormat(log, newLogAddress, newLogSize)))
262 				goto error_out;
263 
264 		/*
265 		 * activate new log
266 		 */
267 		log->base = newLogAddress;
268 		log->size = newLogSize >> (L2LOGPSIZE - sb->s_blocksize_bits);
269 		if ((rc = lmLogInit(log)))
270 			goto error_out;
271 	}
272 
273 	/*
274 	 *	extend block allocation map
275 	 *	---------------------------
276 	 *
277 	 * extendfs() for new extension, retry after crash recovery;
278 	 *
279 	 * note: both logredo() and fsck() rebuild map from
280 	 * the bitmap and configuration parameter from superblock
281 	 * (disregarding all other control information in the map);
282 	 *
283 	 * superblock:
284 	 *  s_size: aggregate size in physical blocks;
285 	 */
286 	/*
287 	 *	compute the new block allocation map configuration
288 	 *
289 	 * map dinode:
290 	 *  di_size: map file size in byte;
291 	 *  di_nblocks: number of blocks allocated for map file;
292 	 *  di_mapsize: number of blocks in aggregate (covered by map);
293 	 * map control page:
294 	 *  db_mapsize: number of blocks in aggregate (covered by map);
295 	 */
296 	newMapSize = newFSSize;
297 	/* number of data pages of new bmap file:
298 	 * roundup new size to full dmap page boundary and
299 	 * add 1 extra dmap page for next extendfs()
300 	 */
301 	t64 = (newMapSize - 1) + BPERDMAP;
302 	newNpages = BLKTODMAPN(t64) + 1;
303 
304 	/*
305 	 *	extend map from current map (WITHOUT growing mapfile)
306 	 *
307 	 * map new extension with unmapped part of the last partial
308 	 * dmap page, if applicable, and extra page(s) allocated
309 	 * at end of bmap by mkfs() or previous extendfs();
310 	 */
311       extendBmap:
312 	/* compute number of blocks requested to extend */
313 	mapSize = bmp->db_mapsize;
314 	XAddress = mapSize;	/* eXtension Address */
315 	XSize = newMapSize - mapSize;	/* eXtension Size */
316 	old_agsize = bmp->db_agsize;	/* We need to know if this changes */
317 
318 	/* compute number of blocks that can be extended by current mapfile */
319 	t64 = dbMapFileSizeToMapSize(ipbmap);
320 	if (mapSize > t64) {
321 		printk(KERN_ERR "jfs_extendfs: mapSize (0x%Lx) > t64 (0x%Lx)\n",
322 		       (long long) mapSize, (long long) t64);
323 		rc = -EIO;
324 		goto error_out;
325 	}
326 	nblocks = min(t64 - mapSize, XSize);
327 
328 	/*
329 	 * update map pages for new extension:
330 	 *
331 	 * update/init dmap and bubble up the control hierarchy
332 	 * incrementally fold up dmaps into upper levels;
333 	 * update bmap control page;
334 	 */
335 	if ((rc = dbExtendFS(ipbmap, XAddress, nblocks)))
336 		goto error_out;
337 
338 	agsizechanged |= (bmp->db_agsize != old_agsize);
339 
340 	/*
341 	 * the map now has extended to cover additional nblocks:
342 	 * dn_mapsize = oldMapsize + nblocks;
343 	 */
344 	/* ipbmap->i_mapsize += nblocks; */
345 	XSize -= nblocks;
346 
347 	/*
348 	 *	grow map file to cover remaining extension
349 	 *	and/or one extra dmap page for next extendfs();
350 	 *
351 	 * allocate new map pages and its backing blocks, and
352 	 * update map file xtree
353 	 */
354 	/* compute number of data pages of current bmap file */
355 	nPages = ipbmap->i_size >> L2PSIZE;
356 
357 	/* need to grow map file ? */
358 	if (nPages == newNpages)
359 		goto finalizeBmap;
360 
361 	/*
362 	 * grow bmap file for the new map pages required:
363 	 *
364 	 * allocate growth at the start of newly extended region;
365 	 * bmap file only grows sequentially, i.e., both data pages
366 	 * and possibly xtree index pages may grow in append mode,
367 	 * s.t. logredo() can reconstruct pre-extension state
368 	 * by washing away bmap file of pages outside s_size boundary;
369 	 */
370 	/*
371 	 * journal map file growth as if a regular file growth:
372 	 * (note: bmap is created with di_mode = IFJOURNAL|IFREG);
373 	 *
374 	 * journaling of bmap file growth is not required since
375 	 * logredo() do/can not use log records of bmap file growth
376 	 * but it provides careful write semantics, pmap update, etc.;
377 	 */
378 	/* synchronous write of data pages: bmap data pages are
379 	 * cached in meta-data cache, and not written out
380 	 * by txCommit();
381 	 */
382 	filemap_fdatawait(ipbmap->i_mapping);
383 	filemap_write_and_wait(ipbmap->i_mapping);
384 	diWriteSpecial(ipbmap, 0);
385 
386 	newPage = nPages;	/* first new page number */
387 	xoff = newPage << sbi->l2nbperpage;
388 	xlen = (newNpages - nPages) << sbi->l2nbperpage;
389 	xlen = min(xlen, (int) nblocks) & ~(sbi->nbperpage - 1);
390 	xaddr = XAddress;
391 
392 	tid = txBegin(sb, COMMIT_FORCE);
393 
394 	if ((rc = xtAppend(tid, ipbmap, 0, xoff, nblocks, &xlen, &xaddr, 0))) {
395 		txEnd(tid);
396 		goto error_out;
397 	}
398 	/* update bmap file size */
399 	ipbmap->i_size += xlen << sbi->l2bsize;
400 	inode_add_bytes(ipbmap, xlen << sbi->l2bsize);
401 
402 	iplist[0] = ipbmap;
403 	rc = txCommit(tid, 1, &iplist[0], COMMIT_FORCE);
404 
405 	txEnd(tid);
406 
407 	if (rc)
408 		goto error_out;
409 
410 	/*
411 	 * map file has been grown now to cover extension to further out;
412 	 * di_size = new map file size;
413 	 *
414 	 * if huge extension, the previous extension based on previous
415 	 * map file size may not have been sufficient to cover whole extension
416 	 * (it could have been used up for new map pages),
417 	 * but the newly grown map file now covers lot bigger new free space
418 	 * available for further extension of map;
419 	 */
420 	/* any more blocks to extend ? */
421 	if (XSize)
422 		goto extendBmap;
423 
424       finalizeBmap:
425 	/* finalize bmap */
426 	dbFinalizeBmap(ipbmap);
427 
428 	/*
429 	 *	update inode allocation map
430 	 *	---------------------------
431 	 *
432 	 * move iag lists from old to new iag;
433 	 * agstart field is not updated for logredo() to reconstruct
434 	 * iag lists if system crash occurs.
435 	 * (computation of ag number from agstart based on agsize
436 	 * will correctly identify the new ag);
437 	 */
438 	/* if new AG size the same as old AG size, done! */
439 	if (agsizechanged) {
440 		if ((rc = diExtendFS(ipimap, ipbmap)))
441 			goto error_out;
442 
443 		/* finalize imap */
444 		if ((rc = diSync(ipimap)))
445 			goto error_out;
446 	}
447 
448 	/*
449 	 *	finalize
450 	 *	--------
451 	 *
452 	 * extension is committed when on-disk super block is
453 	 * updated with new descriptors: logredo will recover
454 	 * crash before it to pre-extension state;
455 	 */
456 
457 	/* sync log to skip log replay of bmap file growth transaction; */
458 	/* lmLogSync(log, 1); */
459 
460 	/*
461 	 * synchronous write bmap global control page;
462 	 * for crash before completion of write
463 	 * logredo() will recover to pre-extendfs state;
464 	 * for crash after completion of write,
465 	 * logredo() will recover post-extendfs state;
466 	 */
467 	if ((rc = dbSync(ipbmap)))
468 		goto error_out;
469 
470 	/*
471 	 * copy primary bmap inode to secondary bmap inode
472 	 */
473 
474 	ipbmap2 = diReadSpecial(sb, BMAP_I, 1);
475 	if (ipbmap2 == NULL) {
476 		printk(KERN_ERR "jfs_extendfs: diReadSpecial(bmap) failed\n");
477 		goto error_out;
478 	}
479 	memcpy(&JFS_IP(ipbmap2)->i_xtroot, &JFS_IP(ipbmap)->i_xtroot, 288);
480 	ipbmap2->i_size = ipbmap->i_size;
481 	ipbmap2->i_blocks = ipbmap->i_blocks;
482 
483 	diWriteSpecial(ipbmap2, 1);
484 	diFreeSpecial(ipbmap2);
485 
486 	/*
487 	 *	update superblock
488 	 */
489 	if ((rc = readSuper(sb, &bh)))
490 		goto error_out;
491 	j_sb = (struct jfs_superblock *)bh->b_data;
492 
493 	/* mark extendfs() completion */
494 	j_sb->s_state &= cpu_to_le32(~FM_EXTENDFS);
495 	j_sb->s_size = cpu_to_le64(bmp->db_mapsize <<
496 				   le16_to_cpu(j_sb->s_l2bfactor));
497 	j_sb->s_agsize = cpu_to_le32(bmp->db_agsize);
498 
499 	/* update inline log space descriptor */
500 	if (sbi->mntflag & JFS_INLINELOG) {
501 		PXDaddress(&(j_sb->s_logpxd), newLogAddress);
502 		PXDlength(&(j_sb->s_logpxd), newLogSize);
503 	}
504 
505 	/* record log's mount serial number */
506 	j_sb->s_logserial = cpu_to_le32(log->serial);
507 
508 	/* update fsck work space descriptor */
509 	PXDaddress(&(j_sb->s_fsckpxd), newFSCKAddress);
510 	PXDlength(&(j_sb->s_fsckpxd), newFSCKSize);
511 	j_sb->s_fscklog = 1;
512 	/* sb->s_fsckloglen remains the same */
513 
514 	/* Update secondary superblock */
515 	bh2 = sb_bread(sb, SUPER2_OFF >> sb->s_blocksize_bits);
516 	if (bh2) {
517 		j_sb2 = (struct jfs_superblock *)bh2->b_data;
518 		memcpy(j_sb2, j_sb, sizeof (struct jfs_superblock));
519 
520 		mark_buffer_dirty(bh);
521 		sync_dirty_buffer(bh2);
522 		brelse(bh2);
523 	}
524 
525 	/* write primary superblock */
526 	mark_buffer_dirty(bh);
527 	sync_dirty_buffer(bh);
528 	brelse(bh);
529 
530 	goto resume;
531 
532       error_out:
533 	jfs_error(sb, "jfs_extendfs");
534 
535       resume:
536 	/*
537 	 *	resume file system transactions
538 	 */
539 	txResume(sb);
540 
541       out:
542 	return rc;
543 }
544