1 /*
2  *   Copyright (C) International Business Machines  Corp., 2000-2003
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/locks.h>
21 
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 extern s64 jfs_get_volume_size(struct super_block *);
33 
34 #define BITSPERPAGE     (PSIZE << 3)
35 #define L2MEGABYTE      20
36 #define MEGABYTE        (1 << L2MEGABYTE)
37 #define MEGABYTE32     (MEGABYTE << 5)
38 
39 /* convert block number to bmap file page number */
40 #define BLKTODMAPN(b)\
41         (((b) >> 13) + ((b) >> 23) + ((b) >> 33) + 3 + 1)
42 
43 /*
44  *      jfs_extendfs()
45  *
46  * function: extend file system;
47  *
48  *   |-------------------------------|----------|----------|
49  *   file system space               fsck       inline log
50  *                                   workspace  space
51  *
52  * input:
53  *      new LVSize: in LV blocks (required)
54  *      new LogSize: in LV blocks (optional)
55  *      new FSSize: in LV blocks (optional)
56  *
57  * new configuration:
58  * 1. set new LogSize as specified or default from new LVSize;
59  * 2. compute new FSCKSize from new LVSize;
60  * 3. set new FSSize as MIN(FSSize, LVSize-(LogSize+FSCKSize)) where
61  *    assert(new FSSize >= old FSSize),
62  *    i.e., file system must not be shrinked;
63  */
jfs_extendfs(struct super_block * sb,s64 newLVSize,int newLogSize)64 int jfs_extendfs(struct super_block *sb, s64 newLVSize, int newLogSize)
65 {
66 	int rc = 0;
67 	struct jfs_sb_info *sbi = JFS_SBI(sb);
68 	struct inode *ipbmap = sbi->ipbmap;
69 	struct inode *ipbmap2;
70 	struct inode *ipimap = sbi->ipimap;
71 	struct jfs_log *log = sbi->log;
72 	struct bmap *bmp = sbi->bmap;
73 	s64 newLogAddress, newFSCKAddress;
74 	int newFSCKSize;
75 	s64 newMapSize = 0, mapSize;
76 	s64 XAddress, XSize, nblocks, xoff, xaddr, t64;
77 	s64 oldLVSize;
78 	s64 newFSSize;
79 	s64 VolumeSize;
80 	int newNpages = 0, nPages, newPage, xlen, t32;
81 	int tid;
82 	int log_formatted = 0;
83 	struct inode *iplist[1];
84 	struct jfs_superblock *j_sb, *j_sb2;
85 	uint old_agsize;
86 	struct buffer_head *bh, *bh2;
87 
88 	/* If the volume hasn't grown, get out now */
89 
90 	if (sbi->mntflag & JFS_INLINELOG)
91 		oldLVSize = addressPXD(&sbi->logpxd) + lengthPXD(&sbi->logpxd);
92 	else
93 		oldLVSize = addressPXD(&sbi->fsckpxd) +
94 		    lengthPXD(&sbi->fsckpxd);
95 
96 	if (oldLVSize >= newLVSize) {
97 		printk(KERN_WARNING
98 		       "jfs_extendfs: volume hasn't grown, returning\n");
99 		goto out;
100 	}
101 
102 	VolumeSize = jfs_get_volume_size(sb);
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 = ((t64 + (BITSPERPAGE - 1)) / 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 shrinked */
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 	if (sbi->mntflag & JFS_INLINELOG) {
214 		/*
215 		 * deactivate old inline log
216 		 */
217 		lmLogShutdown(log);
218 
219 		/*
220 		 * mark on-disk super block for fs in transition;
221 		 *
222 		 * update on-disk superblock for the new space configuration
223 		 * of inline log space and fsck work space descriptors:
224 		 * N.B. FS descriptor is NOT updated;
225 		 *
226 		 * crash recovery:
227 		 * logredo(): if FM_EXTENDFS, return to fsck() for cleanup;
228 		 * fsck(): if FM_EXTENDFS, reformat inline log and fsck
229 		 * workspace from superblock inline log descriptor and fsck
230 		 * workspace descriptor;
231 		 */
232 
233 		/* read in superblock */
234 		if ((rc = readSuper(sb, &bh)))
235 			goto error_out;
236 		j_sb = (struct jfs_superblock *)bh->b_data;
237 
238 		/* mark extendfs() in progress */
239 		j_sb->s_state |= cpu_to_le32(FM_EXTENDFS);
240 		j_sb->s_xsize = cpu_to_le64(newFSSize);
241 		PXDaddress(&j_sb->s_xfsckpxd, newFSCKAddress);
242 		PXDlength(&j_sb->s_xfsckpxd, newFSCKSize);
243 		PXDaddress(&j_sb->s_xlogpxd, newLogAddress);
244 		PXDlength(&j_sb->s_xlogpxd, newLogSize);
245 
246 		/* synchronously update superblock */
247 		mark_buffer_dirty(bh);
248 		ll_rw_block(WRITE, 1, &bh);
249 		wait_on_buffer(bh);
250 		brelse(bh);
251 
252 		/*
253 		 * format new inline log synchronously;
254 		 *
255 		 * crash recovery: if log move in progress,
256 		 * reformat log and exit success;
257 		 */
258 		if (!log_formatted)
259 			if ((rc = lmLogFormat(log, newLogAddress, newLogSize)))
260 				goto error_out;
261 
262 		/*
263 		 * activate new log
264 		 */
265 		log->base = newLogAddress;
266 		log->size = newLogSize >> (L2LOGPSIZE - sb->s_blocksize_bits);
267 		if ((rc = lmLogInit(log)))
268 			goto error_out;
269 	}
270 
271 	/*
272 	 *      extend block allocation map
273 	 *      ---------------------------
274 	 *
275 	 * extendfs() for new extension, retry after crash recovery;
276 	 *
277 	 * note: both logredo() and fsck() rebuild map from
278 	 * the bitmap and configuration parameter from superblock
279 	 * (disregarding all other control information in the map);
280 	 *
281 	 * superblock:
282 	 *  s_size: aggregate size in physical blocks;
283 	 */
284 	/*
285 	 *      compute the new block allocation map configuration
286 	 *
287 	 * map dinode:
288 	 *  di_size: map file size in byte;
289 	 *  di_nblocks: number of blocks allocated for map file;
290 	 *  di_mapsize: number of blocks in aggregate (covered by map);
291 	 * map control page:
292 	 *  db_mapsize: number of blocks in aggregate (covered by map);
293 	 */
294 	newMapSize = newFSSize;
295 	/* number of data pages of new bmap file:
296 	 * roundup new size to full dmap page boundary and
297 	 * add 1 extra dmap page for next extendfs()
298 	 */
299 	t64 = (newMapSize - 1) + BPERDMAP;
300 	newNpages = BLKTODMAPN(t64) + 1;
301 
302 	/*
303 	 *      extend map from current map (WITHOUT growing mapfile)
304 	 *
305 	 * map new extension with unmapped part of the last partial
306 	 * dmap page, if applicable, and extra page(s) allocated
307 	 * at end of bmap by mkfs() or previous extendfs();
308 	 */
309       extendBmap:
310 	/* compute number of blocks requested to extend */
311 	mapSize = bmp->db_mapsize;
312 	XAddress = mapSize;	/* eXtension Address */
313 	XSize = newMapSize - mapSize;	/* eXtension Size */
314 	old_agsize = bmp->db_agsize;	/* We need to know if this changes */
315 
316 	/* compute number of blocks that can be extended by current mapfile */
317 	t64 = dbMapFileSizeToMapSize(ipbmap);
318 	if (mapSize > t64) {
319 		printk(KERN_ERR "jfs_extendfs: mapSize (0x%Lx) > t64 (0x%Lx)\n",
320 		       (long long) mapSize, (long long) t64);
321 		rc = -EIO;
322 		goto error_out;
323 	}
324 	nblocks = min(t64 - mapSize, XSize);
325 
326 	/*
327 	 * update map pages for new extension:
328 	 *
329 	 * update/init dmap and bubble up the control hierarchy
330 	 * incrementally fold up dmaps into upper levels;
331 	 * update bmap control page;
332 	 */
333 	if ((rc = dbExtendFS(ipbmap, XAddress, nblocks)))
334 		goto error_out;
335 	/*
336 	 * the map now has extended to cover additional nblocks:
337 	 * dn_mapsize = oldMapsize + nblocks;
338 	 */
339 	/* ipbmap->i_mapsize += nblocks; */
340 	XSize -= nblocks;
341 
342 	/*
343 	 *      grow map file to cover remaining extension
344 	 *      and/or one extra dmap page for next extendfs();
345 	 *
346 	 * allocate new map pages and its backing blocks, and
347 	 * update map file xtree
348 	 */
349 	/* compute number of data pages of current bmap file */
350 	nPages = ipbmap->i_size >> L2PSIZE;
351 
352 	/* need to grow map file ? */
353 	if (nPages == newNpages)
354 		goto finalizeBmap;
355 
356 	/*
357 	 * grow bmap file for the new map pages required:
358 	 *
359 	 * allocate growth at the start of newly extended region;
360 	 * bmap file only grows sequentially, i.e., both data pages
361 	 * and possibly xtree index pages may grow in append mode,
362 	 * s.t. logredo() can reconstruct pre-extension state
363 	 * by washing away bmap file of pages outside s_size boundary;
364 	 */
365 	/*
366 	 * journal map file growth as if a regular file growth:
367 	 * (note: bmap is created with di_mode = IFJOURNAL|IFREG);
368 	 *
369 	 * journaling of bmap file growth is not required since
370 	 * logredo() do/can not use log records of bmap file growth
371 	 * but it provides careful write semantics, pmap update, etc.;
372 	 */
373 	/* synchronous write of data pages: bmap data pages are
374 	 * cached in meta-data cache, and not written out
375 	 * by txCommit();
376 	 */
377 	fsync_inode_data_buffers(ipbmap);
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 	ipbmap->i_blocks += LBLK2PBLK(sb, xlen);
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 		ll_rw_block(WRITE, 1, &bh2);
516 		wait_on_buffer(bh2);
517 		brelse(bh2);
518 	}
519 
520 	/* write primary superblock */
521 	mark_buffer_dirty(bh);
522 	ll_rw_block(WRITE, 1, &bh);
523 	wait_on_buffer(bh);
524 	brelse(bh);
525 
526 	goto resume;
527 
528       error_out:
529 	jfs_error(sb, "jfs_extendfs");
530 
531       resume:
532 	/*
533 	 *      resume file system transactions
534 	 */
535 	txResume(sb);
536 
537       out:
538 	return rc;
539 }
540