xref: /linux/fs/jfs/jfs_imap.c (revision 60b2737de1b1ddfdb90f3ba622634eb49d6f3603)
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 /*
20  *	jfs_imap.c: inode allocation map manager
21  *
22  * Serialization:
23  *   Each AG has a simple lock which is used to control the serialization of
24  *	the AG level lists.  This lock should be taken first whenever an AG
25  *	level list will be modified or accessed.
26  *
27  *   Each IAG is locked by obtaining the buffer for the IAG page.
28  *
29  *   There is also a inode lock for the inode map inode.  A read lock needs to
30  *	be taken whenever an IAG is read from the map or the global level
31  *	information is read.  A write lock needs to be taken whenever the global
32  *	level information is modified or an atomic operation needs to be used.
33  *
34  *	If more than one IAG is read at one time, the read lock may not
35  *	be given up until all of the IAG's are read.  Otherwise, a deadlock
36  *	may occur when trying to obtain the read lock while another thread
37  *	holding the read lock is waiting on the IAG already being held.
38  *
39  *   The control page of the inode map is read into memory by diMount().
40  *	Thereafter it should only be modified in memory and then it will be
41  *	written out when the filesystem is unmounted by diUnmount().
42  */
43 
44 #include <linux/fs.h>
45 #include <linux/buffer_head.h>
46 #include <linux/pagemap.h>
47 #include <linux/quotaops.h>
48 
49 #include "jfs_incore.h"
50 #include "jfs_inode.h"
51 #include "jfs_filsys.h"
52 #include "jfs_dinode.h"
53 #include "jfs_dmap.h"
54 #include "jfs_imap.h"
55 #include "jfs_metapage.h"
56 #include "jfs_superblock.h"
57 #include "jfs_debug.h"
58 
59 /*
60  * imap locks
61  */
62 /* iag free list lock */
63 #define IAGFREE_LOCK_INIT(imap)		init_MUTEX(&imap->im_freelock)
64 #define IAGFREE_LOCK(imap)		down(&imap->im_freelock)
65 #define IAGFREE_UNLOCK(imap)		up(&imap->im_freelock)
66 
67 /* per ag iag list locks */
68 #define AG_LOCK_INIT(imap,index)	init_MUTEX(&(imap->im_aglock[index]))
69 #define AG_LOCK(imap,agno)		down(&imap->im_aglock[agno])
70 #define AG_UNLOCK(imap,agno)		up(&imap->im_aglock[agno])
71 
72 /*
73  * forward references
74  */
75 static int diAllocAG(struct inomap *, int, boolean_t, struct inode *);
76 static int diAllocAny(struct inomap *, int, boolean_t, struct inode *);
77 static int diAllocBit(struct inomap *, struct iag *, int);
78 static int diAllocExt(struct inomap *, int, struct inode *);
79 static int diAllocIno(struct inomap *, int, struct inode *);
80 static int diFindFree(u32, int);
81 static int diNewExt(struct inomap *, struct iag *, int);
82 static int diNewIAG(struct inomap *, int *, int, struct metapage **);
83 static void duplicateIXtree(struct super_block *, s64, int, s64 *);
84 
85 static int diIAGRead(struct inomap * imap, int, struct metapage **);
86 static int copy_from_dinode(struct dinode *, struct inode *);
87 static void copy_to_dinode(struct dinode *, struct inode *);
88 
89 /*
90  *	debug code for double-checking inode map
91  */
92 /* #define	_JFS_DEBUG_IMAP	1 */
93 
94 #ifdef	_JFS_DEBUG_IMAP
95 #define DBG_DIINIT(imap)	DBGdiInit(imap)
96 #define DBG_DIALLOC(imap, ino)	DBGdiAlloc(imap, ino)
97 #define DBG_DIFREE(imap, ino)	DBGdiFree(imap, ino)
98 
99 static void *DBGdiInit(struct inomap * imap);
100 static void DBGdiAlloc(struct inomap * imap, ino_t ino);
101 static void DBGdiFree(struct inomap * imap, ino_t ino);
102 #else
103 #define DBG_DIINIT(imap)
104 #define DBG_DIALLOC(imap, ino)
105 #define DBG_DIFREE(imap, ino)
106 #endif				/* _JFS_DEBUG_IMAP */
107 
108 /*
109  * NAME:        diMount()
110  *
111  * FUNCTION:    initialize the incore inode map control structures for
112  *		a fileset or aggregate init time.
113  *
114  *              the inode map's control structure (dinomap) is
115  *              brought in from disk and placed in virtual memory.
116  *
117  * PARAMETERS:
118  *      ipimap  - pointer to inode map inode for the aggregate or fileset.
119  *
120  * RETURN VALUES:
121  *      0       - success
122  *      -ENOMEM  - insufficient free virtual memory.
123  *      -EIO  	- i/o error.
124  */
125 int diMount(struct inode *ipimap)
126 {
127 	struct inomap *imap;
128 	struct metapage *mp;
129 	int index;
130 	struct dinomap_disk *dinom_le;
131 
132 	/*
133 	 * allocate/initialize the in-memory inode map control structure
134 	 */
135 	/* allocate the in-memory inode map control structure. */
136 	imap = (struct inomap *) kmalloc(sizeof(struct inomap), GFP_KERNEL);
137 	if (imap == NULL) {
138 		jfs_err("diMount: kmalloc returned NULL!");
139 		return -ENOMEM;
140 	}
141 
142 	/* read the on-disk inode map control structure. */
143 
144 	mp = read_metapage(ipimap,
145 			   IMAPBLKNO << JFS_SBI(ipimap->i_sb)->l2nbperpage,
146 			   PSIZE, 0);
147 	if (mp == NULL) {
148 		kfree(imap);
149 		return -EIO;
150 	}
151 
152 	/* copy the on-disk version to the in-memory version. */
153 	dinom_le = (struct dinomap_disk *) mp->data;
154 	imap->im_freeiag = le32_to_cpu(dinom_le->in_freeiag);
155 	imap->im_nextiag = le32_to_cpu(dinom_le->in_nextiag);
156 	atomic_set(&imap->im_numinos, le32_to_cpu(dinom_le->in_numinos));
157 	atomic_set(&imap->im_numfree, le32_to_cpu(dinom_le->in_numfree));
158 	imap->im_nbperiext = le32_to_cpu(dinom_le->in_nbperiext);
159 	imap->im_l2nbperiext = le32_to_cpu(dinom_le->in_l2nbperiext);
160 	for (index = 0; index < MAXAG; index++) {
161 		imap->im_agctl[index].inofree =
162 		    le32_to_cpu(dinom_le->in_agctl[index].inofree);
163 		imap->im_agctl[index].extfree =
164 		    le32_to_cpu(dinom_le->in_agctl[index].extfree);
165 		imap->im_agctl[index].numinos =
166 		    le32_to_cpu(dinom_le->in_agctl[index].numinos);
167 		imap->im_agctl[index].numfree =
168 		    le32_to_cpu(dinom_le->in_agctl[index].numfree);
169 	}
170 
171 	/* release the buffer. */
172 	release_metapage(mp);
173 
174 	/*
175 	 * allocate/initialize inode allocation map locks
176 	 */
177 	/* allocate and init iag free list lock */
178 	IAGFREE_LOCK_INIT(imap);
179 
180 	/* allocate and init ag list locks */
181 	for (index = 0; index < MAXAG; index++) {
182 		AG_LOCK_INIT(imap, index);
183 	}
184 
185 	/* bind the inode map inode and inode map control structure
186 	 * to each other.
187 	 */
188 	imap->im_ipimap = ipimap;
189 	JFS_IP(ipimap)->i_imap = imap;
190 
191 //      DBG_DIINIT(imap);
192 
193 	return (0);
194 }
195 
196 
197 /*
198  * NAME:        diUnmount()
199  *
200  * FUNCTION:    write to disk the incore inode map control structures for
201  *		a fileset or aggregate at unmount time.
202  *
203  * PARAMETERS:
204  *      ipimap  - pointer to inode map inode for the aggregate or fileset.
205  *
206  * RETURN VALUES:
207  *      0       - success
208  *      -ENOMEM  - insufficient free virtual memory.
209  *      -EIO  	- i/o error.
210  */
211 int diUnmount(struct inode *ipimap, int mounterror)
212 {
213 	struct inomap *imap = JFS_IP(ipimap)->i_imap;
214 
215 	/*
216 	 * update the on-disk inode map control structure
217 	 */
218 
219 	if (!(mounterror || isReadOnly(ipimap)))
220 		diSync(ipimap);
221 
222 	/*
223 	 * Invalidate the page cache buffers
224 	 */
225 	truncate_inode_pages(ipimap->i_mapping, 0);
226 
227 	/*
228 	 * free in-memory control structure
229 	 */
230 	kfree(imap);
231 
232 	return (0);
233 }
234 
235 
236 /*
237  *	diSync()
238  */
239 int diSync(struct inode *ipimap)
240 {
241 	struct dinomap_disk *dinom_le;
242 	struct inomap *imp = JFS_IP(ipimap)->i_imap;
243 	struct metapage *mp;
244 	int index;
245 
246 	/*
247 	 * write imap global conrol page
248 	 */
249 	/* read the on-disk inode map control structure */
250 	mp = get_metapage(ipimap,
251 			  IMAPBLKNO << JFS_SBI(ipimap->i_sb)->l2nbperpage,
252 			  PSIZE, 0);
253 	if (mp == NULL) {
254 		jfs_err("diSync: get_metapage failed!");
255 		return -EIO;
256 	}
257 
258 	/* copy the in-memory version to the on-disk version */
259 	dinom_le = (struct dinomap_disk *) mp->data;
260 	dinom_le->in_freeiag = cpu_to_le32(imp->im_freeiag);
261 	dinom_le->in_nextiag = cpu_to_le32(imp->im_nextiag);
262 	dinom_le->in_numinos = cpu_to_le32(atomic_read(&imp->im_numinos));
263 	dinom_le->in_numfree = cpu_to_le32(atomic_read(&imp->im_numfree));
264 	dinom_le->in_nbperiext = cpu_to_le32(imp->im_nbperiext);
265 	dinom_le->in_l2nbperiext = cpu_to_le32(imp->im_l2nbperiext);
266 	for (index = 0; index < MAXAG; index++) {
267 		dinom_le->in_agctl[index].inofree =
268 		    cpu_to_le32(imp->im_agctl[index].inofree);
269 		dinom_le->in_agctl[index].extfree =
270 		    cpu_to_le32(imp->im_agctl[index].extfree);
271 		dinom_le->in_agctl[index].numinos =
272 		    cpu_to_le32(imp->im_agctl[index].numinos);
273 		dinom_le->in_agctl[index].numfree =
274 		    cpu_to_le32(imp->im_agctl[index].numfree);
275 	}
276 
277 	/* write out the control structure */
278 	write_metapage(mp);
279 
280 	/*
281 	 * write out dirty pages of imap
282 	 */
283 	filemap_fdatawrite(ipimap->i_mapping);
284 	filemap_fdatawait(ipimap->i_mapping);
285 
286 	diWriteSpecial(ipimap, 0);
287 
288 	return (0);
289 }
290 
291 
292 /*
293  * NAME:        diRead()
294  *
295  * FUNCTION:    initialize an incore inode from disk.
296  *
297  *		on entry, the specifed incore inode should itself
298  *		specify the disk inode number corresponding to the
299  *		incore inode (i.e. i_number should be initialized).
300  *
301  *		this routine handles incore inode initialization for
302  *		both "special" and "regular" inodes.  special inodes
303  *		are those required early in the mount process and
304  *	        require special handling since much of the file system
305  *		is not yet initialized.  these "special" inodes are
306  *		identified by a NULL inode map inode pointer and are
307  *		actually initialized by a call to diReadSpecial().
308  *
309  *		for regular inodes, the iag describing the disk inode
310  *		is read from disk to determine the inode extent address
311  *		for the disk inode.  with the inode extent address in
312  *		hand, the page of the extent that contains the disk
313  *		inode is read and the disk inode is copied to the
314  *		incore inode.
315  *
316  * PARAMETERS:
317  *      ip  -  pointer to incore inode to be initialized from disk.
318  *
319  * RETURN VALUES:
320  *      0       - success
321  *      -EIO  	- i/o error.
322  *      -ENOMEM	- insufficient memory
323  *
324  */
325 int diRead(struct inode *ip)
326 {
327 	struct jfs_sb_info *sbi = JFS_SBI(ip->i_sb);
328 	int iagno, ino, extno, rc;
329 	struct inode *ipimap;
330 	struct dinode *dp;
331 	struct iag *iagp;
332 	struct metapage *mp;
333 	s64 blkno, agstart;
334 	struct inomap *imap;
335 	int block_offset;
336 	int inodes_left;
337 	uint pageno;
338 	int rel_inode;
339 
340 	jfs_info("diRead: ino = %ld", ip->i_ino);
341 
342 	ipimap = sbi->ipimap;
343 	JFS_IP(ip)->ipimap = ipimap;
344 
345 	/* determine the iag number for this inode (number) */
346 	iagno = INOTOIAG(ip->i_ino);
347 
348 	/* read the iag */
349 	imap = JFS_IP(ipimap)->i_imap;
350 	IREAD_LOCK(ipimap);
351 	rc = diIAGRead(imap, iagno, &mp);
352 	IREAD_UNLOCK(ipimap);
353 	if (rc) {
354 		jfs_err("diRead: diIAGRead returned %d", rc);
355 		return (rc);
356 	}
357 
358 	iagp = (struct iag *) mp->data;
359 
360 	/* determine inode extent that holds the disk inode */
361 	ino = ip->i_ino & (INOSPERIAG - 1);
362 	extno = ino >> L2INOSPEREXT;
363 
364 	if ((lengthPXD(&iagp->inoext[extno]) != imap->im_nbperiext) ||
365 	    (addressPXD(&iagp->inoext[extno]) == 0)) {
366 		release_metapage(mp);
367 		return -ESTALE;
368 	}
369 
370 	/* get disk block number of the page within the inode extent
371 	 * that holds the disk inode.
372 	 */
373 	blkno = INOPBLK(&iagp->inoext[extno], ino, sbi->l2nbperpage);
374 
375 	/* get the ag for the iag */
376 	agstart = le64_to_cpu(iagp->agstart);
377 
378 	release_metapage(mp);
379 
380 	rel_inode = (ino & (INOSPERPAGE - 1));
381 	pageno = blkno >> sbi->l2nbperpage;
382 
383 	if ((block_offset = ((u32) blkno & (sbi->nbperpage - 1)))) {
384 		/*
385 		 * OS/2 didn't always align inode extents on page boundaries
386 		 */
387 		inodes_left =
388 		     (sbi->nbperpage - block_offset) << sbi->l2niperblk;
389 
390 		if (rel_inode < inodes_left)
391 			rel_inode += block_offset << sbi->l2niperblk;
392 		else {
393 			pageno += 1;
394 			rel_inode -= inodes_left;
395 		}
396 	}
397 
398 	/* read the page of disk inode */
399 	mp = read_metapage(ipimap, pageno << sbi->l2nbperpage, PSIZE, 1);
400 	if (mp == 0) {
401 		jfs_err("diRead: read_metapage failed");
402 		return -EIO;
403 	}
404 
405 	/* locate the the disk inode requested */
406 	dp = (struct dinode *) mp->data;
407 	dp += rel_inode;
408 
409 	if (ip->i_ino != le32_to_cpu(dp->di_number)) {
410 		jfs_error(ip->i_sb, "diRead: i_ino != di_number");
411 		rc = -EIO;
412 	} else if (le32_to_cpu(dp->di_nlink) == 0)
413 		rc = -ESTALE;
414 	else
415 		/* copy the disk inode to the in-memory inode */
416 		rc = copy_from_dinode(dp, ip);
417 
418 	release_metapage(mp);
419 
420 	/* set the ag for the inode */
421 	JFS_IP(ip)->agno = BLKTOAG(agstart, sbi);
422 	JFS_IP(ip)->active_ag = -1;
423 
424 	return (rc);
425 }
426 
427 
428 /*
429  * NAME:        diReadSpecial()
430  *
431  * FUNCTION:    initialize a 'special' inode from disk.
432  *
433  *		this routines handles aggregate level inodes.  The
434  *		inode cache cannot differentiate between the
435  *		aggregate inodes and the filesystem inodes, so we
436  *		handle these here.  We don't actually use the aggregate
437  *	        inode map, since these inodes are at a fixed location
438  *		and in some cases the aggregate inode map isn't initialized
439  *		yet.
440  *
441  * PARAMETERS:
442  *      sb - filesystem superblock
443  *	inum - aggregate inode number
444  *	secondary - 1 if secondary aggregate inode table
445  *
446  * RETURN VALUES:
447  *      new inode	- success
448  *      NULL		- i/o error.
449  */
450 struct inode *diReadSpecial(struct super_block *sb, ino_t inum, int secondary)
451 {
452 	struct jfs_sb_info *sbi = JFS_SBI(sb);
453 	uint address;
454 	struct dinode *dp;
455 	struct inode *ip;
456 	struct metapage *mp;
457 
458 	ip = new_inode(sb);
459 	if (ip == NULL) {
460 		jfs_err("diReadSpecial: new_inode returned NULL!");
461 		return ip;
462 	}
463 
464 	if (secondary) {
465 		address = addressPXD(&sbi->ait2) >> sbi->l2nbperpage;
466 		JFS_IP(ip)->ipimap = sbi->ipaimap2;
467 	} else {
468 		address = AITBL_OFF >> L2PSIZE;
469 		JFS_IP(ip)->ipimap = sbi->ipaimap;
470 	}
471 
472 	ASSERT(inum < INOSPEREXT);
473 
474 	ip->i_ino = inum;
475 
476 	address += inum >> 3;	/* 8 inodes per 4K page */
477 
478 	/* read the page of fixed disk inode (AIT) in raw mode */
479 	mp = read_metapage(ip, address << sbi->l2nbperpage, PSIZE, 1);
480 	if (mp == NULL) {
481 		ip->i_nlink = 1;	/* Don't want iput() deleting it */
482 		iput(ip);
483 		return (NULL);
484 	}
485 
486 	/* get the pointer to the disk inode of interest */
487 	dp = (struct dinode *) (mp->data);
488 	dp += inum % 8;		/* 8 inodes per 4K page */
489 
490 	/* copy on-disk inode to in-memory inode */
491 	if ((copy_from_dinode(dp, ip)) != 0) {
492 		/* handle bad return by returning NULL for ip */
493 		ip->i_nlink = 1;	/* Don't want iput() deleting it */
494 		iput(ip);
495 		/* release the page */
496 		release_metapage(mp);
497 		return (NULL);
498 
499 	}
500 
501 	ip->i_mapping->a_ops = &jfs_metapage_aops;
502 	mapping_set_gfp_mask(ip->i_mapping, GFP_NOFS);
503 
504 	/* Allocations to metadata inodes should not affect quotas */
505 	ip->i_flags |= S_NOQUOTA;
506 
507 	if ((inum == FILESYSTEM_I) && (JFS_IP(ip)->ipimap == sbi->ipaimap)) {
508 		sbi->gengen = le32_to_cpu(dp->di_gengen);
509 		sbi->inostamp = le32_to_cpu(dp->di_inostamp);
510 	}
511 
512 	/* release the page */
513 	release_metapage(mp);
514 
515 	return (ip);
516 }
517 
518 /*
519  * NAME:        diWriteSpecial()
520  *
521  * FUNCTION:    Write the special inode to disk
522  *
523  * PARAMETERS:
524  *      ip - special inode
525  *	secondary - 1 if secondary aggregate inode table
526  *
527  * RETURN VALUES: none
528  */
529 
530 void diWriteSpecial(struct inode *ip, int secondary)
531 {
532 	struct jfs_sb_info *sbi = JFS_SBI(ip->i_sb);
533 	uint address;
534 	struct dinode *dp;
535 	ino_t inum = ip->i_ino;
536 	struct metapage *mp;
537 
538 	ip->i_state &= ~I_DIRTY;
539 
540 	if (secondary)
541 		address = addressPXD(&sbi->ait2) >> sbi->l2nbperpage;
542 	else
543 		address = AITBL_OFF >> L2PSIZE;
544 
545 	ASSERT(inum < INOSPEREXT);
546 
547 	address += inum >> 3;	/* 8 inodes per 4K page */
548 
549 	/* read the page of fixed disk inode (AIT) in raw mode */
550 	mp = read_metapage(ip, address << sbi->l2nbperpage, PSIZE, 1);
551 	if (mp == NULL) {
552 		jfs_err("diWriteSpecial: failed to read aggregate inode "
553 			"extent!");
554 		return;
555 	}
556 
557 	/* get the pointer to the disk inode of interest */
558 	dp = (struct dinode *) (mp->data);
559 	dp += inum % 8;		/* 8 inodes per 4K page */
560 
561 	/* copy on-disk inode to in-memory inode */
562 	copy_to_dinode(dp, ip);
563 	memcpy(&dp->di_xtroot, &JFS_IP(ip)->i_xtroot, 288);
564 
565 	if (inum == FILESYSTEM_I)
566 		dp->di_gengen = cpu_to_le32(sbi->gengen);
567 
568 	/* write the page */
569 	write_metapage(mp);
570 }
571 
572 /*
573  * NAME:        diFreeSpecial()
574  *
575  * FUNCTION:    Free allocated space for special inode
576  */
577 void diFreeSpecial(struct inode *ip)
578 {
579 	if (ip == NULL) {
580 		jfs_err("diFreeSpecial called with NULL ip!");
581 		return;
582 	}
583 	filemap_fdatawrite(ip->i_mapping);
584 	filemap_fdatawait(ip->i_mapping);
585 	truncate_inode_pages(ip->i_mapping, 0);
586 	iput(ip);
587 }
588 
589 
590 
591 /*
592  * NAME:        diWrite()
593  *
594  * FUNCTION:    write the on-disk inode portion of the in-memory inode
595  *		to its corresponding on-disk inode.
596  *
597  *		on entry, the specifed incore inode should itself
598  *		specify the disk inode number corresponding to the
599  *		incore inode (i.e. i_number should be initialized).
600  *
601  *		the inode contains the inode extent address for the disk
602  *		inode.  with the inode extent address in hand, the
603  *		page of the extent that contains the disk inode is
604  *		read and the disk inode portion of the incore inode
605  *		is copied to the disk inode.
606  *
607  * PARAMETERS:
608  *	tid -  transacation id
609  *      ip  -  pointer to incore inode to be written to the inode extent.
610  *
611  * RETURN VALUES:
612  *      0       - success
613  *      -EIO  	- i/o error.
614  */
615 int diWrite(tid_t tid, struct inode *ip)
616 {
617 	struct jfs_sb_info *sbi = JFS_SBI(ip->i_sb);
618 	struct jfs_inode_info *jfs_ip = JFS_IP(ip);
619 	int rc = 0;
620 	s32 ino;
621 	struct dinode *dp;
622 	s64 blkno;
623 	int block_offset;
624 	int inodes_left;
625 	struct metapage *mp;
626 	uint pageno;
627 	int rel_inode;
628 	int dioffset;
629 	struct inode *ipimap;
630 	uint type;
631 	lid_t lid;
632 	struct tlock *ditlck, *tlck;
633 	struct linelock *dilinelock, *ilinelock;
634 	struct lv *lv;
635 	int n;
636 
637 	ipimap = jfs_ip->ipimap;
638 
639 	ino = ip->i_ino & (INOSPERIAG - 1);
640 
641 	if (!addressPXD(&(jfs_ip->ixpxd)) ||
642 	    (lengthPXD(&(jfs_ip->ixpxd)) !=
643 	     JFS_IP(ipimap)->i_imap->im_nbperiext)) {
644 		jfs_error(ip->i_sb, "diWrite: ixpxd invalid");
645 		return -EIO;
646 	}
647 
648 	/*
649 	 * read the page of disk inode containing the specified inode:
650 	 */
651 	/* compute the block address of the page */
652 	blkno = INOPBLK(&(jfs_ip->ixpxd), ino, sbi->l2nbperpage);
653 
654 	rel_inode = (ino & (INOSPERPAGE - 1));
655 	pageno = blkno >> sbi->l2nbperpage;
656 
657 	if ((block_offset = ((u32) blkno & (sbi->nbperpage - 1)))) {
658 		/*
659 		 * OS/2 didn't always align inode extents on page boundaries
660 		 */
661 		inodes_left =
662 		    (sbi->nbperpage - block_offset) << sbi->l2niperblk;
663 
664 		if (rel_inode < inodes_left)
665 			rel_inode += block_offset << sbi->l2niperblk;
666 		else {
667 			pageno += 1;
668 			rel_inode -= inodes_left;
669 		}
670 	}
671 	/* read the page of disk inode */
672       retry:
673 	mp = read_metapage(ipimap, pageno << sbi->l2nbperpage, PSIZE, 1);
674 	if (mp == 0)
675 		return -EIO;
676 
677 	/* get the pointer to the disk inode */
678 	dp = (struct dinode *) mp->data;
679 	dp += rel_inode;
680 
681 	dioffset = (ino & (INOSPERPAGE - 1)) << L2DISIZE;
682 
683 	/*
684 	 * acquire transaction lock on the on-disk inode;
685 	 * N.B. tlock is acquired on ipimap not ip;
686 	 */
687 	if ((ditlck =
688 	     txLock(tid, ipimap, mp, tlckINODE | tlckENTRY)) == NULL)
689 		goto retry;
690 	dilinelock = (struct linelock *) & ditlck->lock;
691 
692 	/*
693 	 * copy btree root from in-memory inode to on-disk inode
694 	 *
695 	 * (tlock is taken from inline B+-tree root in in-memory
696 	 * inode when the B+-tree root is updated, which is pointed
697 	 * by jfs_ip->blid as well as being on tx tlock list)
698 	 *
699 	 * further processing of btree root is based on the copy
700 	 * in in-memory inode, where txLog() will log from, and,
701 	 * for xtree root, txUpdateMap() will update map and reset
702 	 * XAD_NEW bit;
703 	 */
704 
705 	if (S_ISDIR(ip->i_mode) && (lid = jfs_ip->xtlid)) {
706 		/*
707 		 * This is the special xtree inside the directory for storing
708 		 * the directory table
709 		 */
710 		xtpage_t *p, *xp;
711 		xad_t *xad;
712 
713 		jfs_ip->xtlid = 0;
714 		tlck = lid_to_tlock(lid);
715 		assert(tlck->type & tlckXTREE);
716 		tlck->type |= tlckBTROOT;
717 		tlck->mp = mp;
718 		ilinelock = (struct linelock *) & tlck->lock;
719 
720 		/*
721 		 * copy xtree root from inode to dinode:
722 		 */
723 		p = &jfs_ip->i_xtroot;
724 		xp = (xtpage_t *) &dp->di_dirtable;
725 		lv = ilinelock->lv;
726 		for (n = 0; n < ilinelock->index; n++, lv++) {
727 			memcpy(&xp->xad[lv->offset], &p->xad[lv->offset],
728 			       lv->length << L2XTSLOTSIZE);
729 		}
730 
731 		/* reset on-disk (metadata page) xtree XAD_NEW bit */
732 		xad = &xp->xad[XTENTRYSTART];
733 		for (n = XTENTRYSTART;
734 		     n < le16_to_cpu(xp->header.nextindex); n++, xad++)
735 			if (xad->flag & (XAD_NEW | XAD_EXTENDED))
736 				xad->flag &= ~(XAD_NEW | XAD_EXTENDED);
737 	}
738 
739 	if ((lid = jfs_ip->blid) == 0)
740 		goto inlineData;
741 	jfs_ip->blid = 0;
742 
743 	tlck = lid_to_tlock(lid);
744 	type = tlck->type;
745 	tlck->type |= tlckBTROOT;
746 	tlck->mp = mp;
747 	ilinelock = (struct linelock *) & tlck->lock;
748 
749 	/*
750 	 *      regular file: 16 byte (XAD slot) granularity
751 	 */
752 	if (type & tlckXTREE) {
753 		xtpage_t *p, *xp;
754 		xad_t *xad;
755 
756 		/*
757 		 * copy xtree root from inode to dinode:
758 		 */
759 		p = &jfs_ip->i_xtroot;
760 		xp = &dp->di_xtroot;
761 		lv = ilinelock->lv;
762 		for (n = 0; n < ilinelock->index; n++, lv++) {
763 			memcpy(&xp->xad[lv->offset], &p->xad[lv->offset],
764 			       lv->length << L2XTSLOTSIZE);
765 		}
766 
767 		/* reset on-disk (metadata page) xtree XAD_NEW bit */
768 		xad = &xp->xad[XTENTRYSTART];
769 		for (n = XTENTRYSTART;
770 		     n < le16_to_cpu(xp->header.nextindex); n++, xad++)
771 			if (xad->flag & (XAD_NEW | XAD_EXTENDED))
772 				xad->flag &= ~(XAD_NEW | XAD_EXTENDED);
773 	}
774 	/*
775 	 *      directory: 32 byte (directory entry slot) granularity
776 	 */
777 	else if (type & tlckDTREE) {
778 		dtpage_t *p, *xp;
779 
780 		/*
781 		 * copy dtree root from inode to dinode:
782 		 */
783 		p = (dtpage_t *) &jfs_ip->i_dtroot;
784 		xp = (dtpage_t *) & dp->di_dtroot;
785 		lv = ilinelock->lv;
786 		for (n = 0; n < ilinelock->index; n++, lv++) {
787 			memcpy(&xp->slot[lv->offset], &p->slot[lv->offset],
788 			       lv->length << L2DTSLOTSIZE);
789 		}
790 	} else {
791 		jfs_err("diWrite: UFO tlock");
792 	}
793 
794       inlineData:
795 	/*
796 	 * copy inline symlink from in-memory inode to on-disk inode
797 	 */
798 	if (S_ISLNK(ip->i_mode) && ip->i_size < IDATASIZE) {
799 		lv = & dilinelock->lv[dilinelock->index];
800 		lv->offset = (dioffset + 2 * 128) >> L2INODESLOTSIZE;
801 		lv->length = 2;
802 		memcpy(&dp->di_fastsymlink, jfs_ip->i_inline, IDATASIZE);
803 		dilinelock->index++;
804 	}
805 	/*
806 	 * copy inline data from in-memory inode to on-disk inode:
807 	 * 128 byte slot granularity
808 	 */
809 	if (test_cflag(COMMIT_Inlineea, ip)) {
810 		lv = & dilinelock->lv[dilinelock->index];
811 		lv->offset = (dioffset + 3 * 128) >> L2INODESLOTSIZE;
812 		lv->length = 1;
813 		memcpy(&dp->di_inlineea, jfs_ip->i_inline_ea, INODESLOTSIZE);
814 		dilinelock->index++;
815 
816 		clear_cflag(COMMIT_Inlineea, ip);
817 	}
818 
819 	/*
820 	 *      lock/copy inode base: 128 byte slot granularity
821 	 */
822 // baseDinode:
823 	lv = & dilinelock->lv[dilinelock->index];
824 	lv->offset = dioffset >> L2INODESLOTSIZE;
825 	copy_to_dinode(dp, ip);
826 	if (test_and_clear_cflag(COMMIT_Dirtable, ip)) {
827 		lv->length = 2;
828 		memcpy(&dp->di_dirtable, &jfs_ip->i_dirtable, 96);
829 	} else
830 		lv->length = 1;
831 	dilinelock->index++;
832 
833 #ifdef _JFS_FASTDASD
834 	/*
835 	 * We aren't logging changes to the DASD used in directory inodes,
836 	 * but we need to write them to disk.  If we don't unmount cleanly,
837 	 * mount will recalculate the DASD used.
838 	 */
839 	if (S_ISDIR(ip->i_mode)
840 	    && (ip->i_ipmnt->i_mntflag & JFS_DASD_ENABLED))
841 		memcpy(&dp->di_DASD, &ip->i_DASD, sizeof(struct dasd));
842 #endif				/*  _JFS_FASTDASD */
843 
844 	/* release the buffer holding the updated on-disk inode.
845 	 * the buffer will be later written by commit processing.
846 	 */
847 	write_metapage(mp);
848 
849 	return (rc);
850 }
851 
852 
853 /*
854  * NAME:        diFree(ip)
855  *
856  * FUNCTION:    free a specified inode from the inode working map
857  *		for a fileset or aggregate.
858  *
859  *		if the inode to be freed represents the first (only)
860  *		free inode within the iag, the iag will be placed on
861  *		the ag free inode list.
862  *
863  *		freeing the inode will cause the inode extent to be
864  *		freed if the inode is the only allocated inode within
865  *		the extent.  in this case all the disk resource backing
866  *		up the inode extent will be freed. in addition, the iag
867  *		will be placed on the ag extent free list if the extent
868  *		is the first free extent in the iag.  if freeing the
869  *		extent also means that no free inodes will exist for
870  *		the iag, the iag will also be removed from the ag free
871  *		inode list.
872  *
873  *		the iag describing the inode will be freed if the extent
874  *		is to be freed and it is the only backed extent within
875  *		the iag.  in this case, the iag will be removed from the
876  *		ag free extent list and ag free inode list and placed on
877  *		the inode map's free iag list.
878  *
879  *		a careful update approach is used to provide consistency
880  *		in the face of updates to multiple buffers.  under this
881  *		approach, all required buffers are obtained before making
882  *		any updates and are held until all updates are complete.
883  *
884  * PARAMETERS:
885  *      ip  	- inode to be freed.
886  *
887  * RETURN VALUES:
888  *      0       - success
889  *      -EIO  	- i/o error.
890  */
891 int diFree(struct inode *ip)
892 {
893 	int rc;
894 	ino_t inum = ip->i_ino;
895 	struct iag *iagp, *aiagp, *biagp, *ciagp, *diagp;
896 	struct metapage *mp, *amp, *bmp, *cmp, *dmp;
897 	int iagno, ino, extno, bitno, sword, agno;
898 	int back, fwd;
899 	u32 bitmap, mask;
900 	struct inode *ipimap = JFS_SBI(ip->i_sb)->ipimap;
901 	struct inomap *imap = JFS_IP(ipimap)->i_imap;
902 	pxd_t freepxd;
903 	tid_t tid;
904 	struct inode *iplist[3];
905 	struct tlock *tlck;
906 	struct pxd_lock *pxdlock;
907 
908 	/*
909 	 * This is just to suppress compiler warnings.  The same logic that
910 	 * references these variables is used to initialize them.
911 	 */
912 	aiagp = biagp = ciagp = diagp = NULL;
913 
914 	/* get the iag number containing the inode.
915 	 */
916 	iagno = INOTOIAG(inum);
917 
918 	/* make sure that the iag is contained within
919 	 * the map.
920 	 */
921 	if (iagno >= imap->im_nextiag) {
922 		dump_mem("imap", imap, 32);
923 		jfs_error(ip->i_sb,
924 			  "diFree: inum = %d, iagno = %d, nextiag = %d",
925 			  (uint) inum, iagno, imap->im_nextiag);
926 		return -EIO;
927 	}
928 
929 	/* get the allocation group for this ino.
930 	 */
931 	agno = JFS_IP(ip)->agno;
932 
933 	/* Lock the AG specific inode map information
934 	 */
935 	AG_LOCK(imap, agno);
936 
937 	/* Obtain read lock in imap inode.  Don't release it until we have
938 	 * read all of the IAG's that we are going to.
939 	 */
940 	IREAD_LOCK(ipimap);
941 
942 	/* read the iag.
943 	 */
944 	if ((rc = diIAGRead(imap, iagno, &mp))) {
945 		IREAD_UNLOCK(ipimap);
946 		AG_UNLOCK(imap, agno);
947 		return (rc);
948 	}
949 	iagp = (struct iag *) mp->data;
950 
951 	/* get the inode number and extent number of the inode within
952 	 * the iag and the inode number within the extent.
953 	 */
954 	ino = inum & (INOSPERIAG - 1);
955 	extno = ino >> L2INOSPEREXT;
956 	bitno = ino & (INOSPEREXT - 1);
957 	mask = HIGHORDER >> bitno;
958 
959 	if (!(le32_to_cpu(iagp->wmap[extno]) & mask)) {
960 		jfs_error(ip->i_sb,
961 			  "diFree: wmap shows inode already free");
962 	}
963 
964 	if (!addressPXD(&iagp->inoext[extno])) {
965 		release_metapage(mp);
966 		IREAD_UNLOCK(ipimap);
967 		AG_UNLOCK(imap, agno);
968 		jfs_error(ip->i_sb, "diFree: invalid inoext");
969 		return -EIO;
970 	}
971 
972 	/* compute the bitmap for the extent reflecting the freed inode.
973 	 */
974 	bitmap = le32_to_cpu(iagp->wmap[extno]) & ~mask;
975 
976 	if (imap->im_agctl[agno].numfree > imap->im_agctl[agno].numinos) {
977 		release_metapage(mp);
978 		IREAD_UNLOCK(ipimap);
979 		AG_UNLOCK(imap, agno);
980 		jfs_error(ip->i_sb, "diFree: numfree > numinos");
981 		return -EIO;
982 	}
983 	/*
984 	 *      inode extent still has some inodes or below low water mark:
985 	 *      keep the inode extent;
986 	 */
987 	if (bitmap ||
988 	    imap->im_agctl[agno].numfree < 96 ||
989 	    (imap->im_agctl[agno].numfree < 288 &&
990 	     (((imap->im_agctl[agno].numfree * 100) /
991 	       imap->im_agctl[agno].numinos) <= 25))) {
992 		/* if the iag currently has no free inodes (i.e.,
993 		 * the inode being freed is the first free inode of iag),
994 		 * insert the iag at head of the inode free list for the ag.
995 		 */
996 		if (iagp->nfreeinos == 0) {
997 			/* check if there are any iags on the ag inode
998 			 * free list.  if so, read the first one so that
999 			 * we can link the current iag onto the list at
1000 			 * the head.
1001 			 */
1002 			if ((fwd = imap->im_agctl[agno].inofree) >= 0) {
1003 				/* read the iag that currently is the head
1004 				 * of the list.
1005 				 */
1006 				if ((rc = diIAGRead(imap, fwd, &amp))) {
1007 					IREAD_UNLOCK(ipimap);
1008 					AG_UNLOCK(imap, agno);
1009 					release_metapage(mp);
1010 					return (rc);
1011 				}
1012 				aiagp = (struct iag *) amp->data;
1013 
1014 				/* make current head point back to the iag.
1015 				 */
1016 				aiagp->inofreeback = cpu_to_le32(iagno);
1017 
1018 				write_metapage(amp);
1019 			}
1020 
1021 			/* iag points forward to current head and iag
1022 			 * becomes the new head of the list.
1023 			 */
1024 			iagp->inofreefwd =
1025 			    cpu_to_le32(imap->im_agctl[agno].inofree);
1026 			iagp->inofreeback = cpu_to_le32(-1);
1027 			imap->im_agctl[agno].inofree = iagno;
1028 		}
1029 		IREAD_UNLOCK(ipimap);
1030 
1031 		/* update the free inode summary map for the extent if
1032 		 * freeing the inode means the extent will now have free
1033 		 * inodes (i.e., the inode being freed is the first free
1034 		 * inode of extent),
1035 		 */
1036 		if (iagp->wmap[extno] == cpu_to_le32(ONES)) {
1037 			sword = extno >> L2EXTSPERSUM;
1038 			bitno = extno & (EXTSPERSUM - 1);
1039 			iagp->inosmap[sword] &=
1040 			    cpu_to_le32(~(HIGHORDER >> bitno));
1041 		}
1042 
1043 		/* update the bitmap.
1044 		 */
1045 		iagp->wmap[extno] = cpu_to_le32(bitmap);
1046 		DBG_DIFREE(imap, inum);
1047 
1048 		/* update the free inode counts at the iag, ag and
1049 		 * map level.
1050 		 */
1051 		iagp->nfreeinos =
1052 		    cpu_to_le32(le32_to_cpu(iagp->nfreeinos) + 1);
1053 		imap->im_agctl[agno].numfree += 1;
1054 		atomic_inc(&imap->im_numfree);
1055 
1056 		/* release the AG inode map lock
1057 		 */
1058 		AG_UNLOCK(imap, agno);
1059 
1060 		/* write the iag */
1061 		write_metapage(mp);
1062 
1063 		return (0);
1064 	}
1065 
1066 
1067 	/*
1068 	 *      inode extent has become free and above low water mark:
1069 	 *      free the inode extent;
1070 	 */
1071 
1072 	/*
1073 	 *      prepare to update iag list(s) (careful update step 1)
1074 	 */
1075 	amp = bmp = cmp = dmp = NULL;
1076 	fwd = back = -1;
1077 
1078 	/* check if the iag currently has no free extents.  if so,
1079 	 * it will be placed on the head of the ag extent free list.
1080 	 */
1081 	if (iagp->nfreeexts == 0) {
1082 		/* check if the ag extent free list has any iags.
1083 		 * if so, read the iag at the head of the list now.
1084 		 * this (head) iag will be updated later to reflect
1085 		 * the addition of the current iag at the head of
1086 		 * the list.
1087 		 */
1088 		if ((fwd = imap->im_agctl[agno].extfree) >= 0) {
1089 			if ((rc = diIAGRead(imap, fwd, &amp)))
1090 				goto error_out;
1091 			aiagp = (struct iag *) amp->data;
1092 		}
1093 	} else {
1094 		/* iag has free extents. check if the addition of a free
1095 		 * extent will cause all extents to be free within this
1096 		 * iag.  if so, the iag will be removed from the ag extent
1097 		 * free list and placed on the inode map's free iag list.
1098 		 */
1099 		if (iagp->nfreeexts == cpu_to_le32(EXTSPERIAG - 1)) {
1100 			/* in preparation for removing the iag from the
1101 			 * ag extent free list, read the iags preceeding
1102 			 * and following the iag on the ag extent free
1103 			 * list.
1104 			 */
1105 			if ((fwd = le32_to_cpu(iagp->extfreefwd)) >= 0) {
1106 				if ((rc = diIAGRead(imap, fwd, &amp)))
1107 					goto error_out;
1108 				aiagp = (struct iag *) amp->data;
1109 			}
1110 
1111 			if ((back = le32_to_cpu(iagp->extfreeback)) >= 0) {
1112 				if ((rc = diIAGRead(imap, back, &bmp)))
1113 					goto error_out;
1114 				biagp = (struct iag *) bmp->data;
1115 			}
1116 		}
1117 	}
1118 
1119 	/* remove the iag from the ag inode free list if freeing
1120 	 * this extent cause the iag to have no free inodes.
1121 	 */
1122 	if (iagp->nfreeinos == cpu_to_le32(INOSPEREXT - 1)) {
1123 		int inofreeback = le32_to_cpu(iagp->inofreeback);
1124 		int inofreefwd = le32_to_cpu(iagp->inofreefwd);
1125 
1126 		/* in preparation for removing the iag from the
1127 		 * ag inode free list, read the iags preceeding
1128 		 * and following the iag on the ag inode free
1129 		 * list.  before reading these iags, we must make
1130 		 * sure that we already don't have them in hand
1131 		 * from up above, since re-reading an iag (buffer)
1132 		 * we are currently holding would cause a deadlock.
1133 		 */
1134 		if (inofreefwd >= 0) {
1135 
1136 			if (inofreefwd == fwd)
1137 				ciagp = (struct iag *) amp->data;
1138 			else if (inofreefwd == back)
1139 				ciagp = (struct iag *) bmp->data;
1140 			else {
1141 				if ((rc =
1142 				     diIAGRead(imap, inofreefwd, &cmp)))
1143 					goto error_out;
1144 				ciagp = (struct iag *) cmp->data;
1145 			}
1146 			assert(ciagp != NULL);
1147 		}
1148 
1149 		if (inofreeback >= 0) {
1150 			if (inofreeback == fwd)
1151 				diagp = (struct iag *) amp->data;
1152 			else if (inofreeback == back)
1153 				diagp = (struct iag *) bmp->data;
1154 			else {
1155 				if ((rc =
1156 				     diIAGRead(imap, inofreeback, &dmp)))
1157 					goto error_out;
1158 				diagp = (struct iag *) dmp->data;
1159 			}
1160 			assert(diagp != NULL);
1161 		}
1162 	}
1163 
1164 	IREAD_UNLOCK(ipimap);
1165 
1166 	/*
1167 	 * invalidate any page of the inode extent freed from buffer cache;
1168 	 */
1169 	freepxd = iagp->inoext[extno];
1170 	invalidate_pxd_metapages(ip, freepxd);
1171 
1172 	/*
1173 	 *      update iag list(s) (careful update step 2)
1174 	 */
1175 	/* add the iag to the ag extent free list if this is the
1176 	 * first free extent for the iag.
1177 	 */
1178 	if (iagp->nfreeexts == 0) {
1179 		if (fwd >= 0)
1180 			aiagp->extfreeback = cpu_to_le32(iagno);
1181 
1182 		iagp->extfreefwd =
1183 		    cpu_to_le32(imap->im_agctl[agno].extfree);
1184 		iagp->extfreeback = cpu_to_le32(-1);
1185 		imap->im_agctl[agno].extfree = iagno;
1186 	} else {
1187 		/* remove the iag from the ag extent list if all extents
1188 		 * are now free and place it on the inode map iag free list.
1189 		 */
1190 		if (iagp->nfreeexts == cpu_to_le32(EXTSPERIAG - 1)) {
1191 			if (fwd >= 0)
1192 				aiagp->extfreeback = iagp->extfreeback;
1193 
1194 			if (back >= 0)
1195 				biagp->extfreefwd = iagp->extfreefwd;
1196 			else
1197 				imap->im_agctl[agno].extfree =
1198 				    le32_to_cpu(iagp->extfreefwd);
1199 
1200 			iagp->extfreefwd = iagp->extfreeback = cpu_to_le32(-1);
1201 
1202 			IAGFREE_LOCK(imap);
1203 			iagp->iagfree = cpu_to_le32(imap->im_freeiag);
1204 			imap->im_freeiag = iagno;
1205 			IAGFREE_UNLOCK(imap);
1206 		}
1207 	}
1208 
1209 	/* remove the iag from the ag inode free list if freeing
1210 	 * this extent causes the iag to have no free inodes.
1211 	 */
1212 	if (iagp->nfreeinos == cpu_to_le32(INOSPEREXT - 1)) {
1213 		if ((int) le32_to_cpu(iagp->inofreefwd) >= 0)
1214 			ciagp->inofreeback = iagp->inofreeback;
1215 
1216 		if ((int) le32_to_cpu(iagp->inofreeback) >= 0)
1217 			diagp->inofreefwd = iagp->inofreefwd;
1218 		else
1219 			imap->im_agctl[agno].inofree =
1220 			    le32_to_cpu(iagp->inofreefwd);
1221 
1222 		iagp->inofreefwd = iagp->inofreeback = cpu_to_le32(-1);
1223 	}
1224 
1225 	/* update the inode extent address and working map
1226 	 * to reflect the free extent.
1227 	 * the permanent map should have been updated already
1228 	 * for the inode being freed.
1229 	 */
1230 	if (iagp->pmap[extno] != 0) {
1231 		jfs_error(ip->i_sb, "diFree: the pmap does not show inode free");
1232 	}
1233 	iagp->wmap[extno] = 0;
1234 	DBG_DIFREE(imap, inum);
1235 	PXDlength(&iagp->inoext[extno], 0);
1236 	PXDaddress(&iagp->inoext[extno], 0);
1237 
1238 	/* update the free extent and free inode summary maps
1239 	 * to reflect the freed extent.
1240 	 * the inode summary map is marked to indicate no inodes
1241 	 * available for the freed extent.
1242 	 */
1243 	sword = extno >> L2EXTSPERSUM;
1244 	bitno = extno & (EXTSPERSUM - 1);
1245 	mask = HIGHORDER >> bitno;
1246 	iagp->inosmap[sword] |= cpu_to_le32(mask);
1247 	iagp->extsmap[sword] &= cpu_to_le32(~mask);
1248 
1249 	/* update the number of free inodes and number of free extents
1250 	 * for the iag.
1251 	 */
1252 	iagp->nfreeinos = cpu_to_le32(le32_to_cpu(iagp->nfreeinos) -
1253 				      (INOSPEREXT - 1));
1254 	iagp->nfreeexts = cpu_to_le32(le32_to_cpu(iagp->nfreeexts) + 1);
1255 
1256 	/* update the number of free inodes and backed inodes
1257 	 * at the ag and inode map level.
1258 	 */
1259 	imap->im_agctl[agno].numfree -= (INOSPEREXT - 1);
1260 	imap->im_agctl[agno].numinos -= INOSPEREXT;
1261 	atomic_sub(INOSPEREXT - 1, &imap->im_numfree);
1262 	atomic_sub(INOSPEREXT, &imap->im_numinos);
1263 
1264 	if (amp)
1265 		write_metapage(amp);
1266 	if (bmp)
1267 		write_metapage(bmp);
1268 	if (cmp)
1269 		write_metapage(cmp);
1270 	if (dmp)
1271 		write_metapage(dmp);
1272 
1273 	/*
1274 	 * start transaction to update block allocation map
1275 	 * for the inode extent freed;
1276 	 *
1277 	 * N.B. AG_LOCK is released and iag will be released below, and
1278 	 * other thread may allocate inode from/reusing the ixad freed
1279 	 * BUT with new/different backing inode extent from the extent
1280 	 * to be freed by the transaction;
1281 	 */
1282 	tid = txBegin(ipimap->i_sb, COMMIT_FORCE);
1283 	down(&JFS_IP(ipimap)->commit_sem);
1284 
1285 	/* acquire tlock of the iag page of the freed ixad
1286 	 * to force the page NOHOMEOK (even though no data is
1287 	 * logged from the iag page) until NOREDOPAGE|FREEXTENT log
1288 	 * for the free of the extent is committed;
1289 	 * write FREEXTENT|NOREDOPAGE log record
1290 	 * N.B. linelock is overlaid as freed extent descriptor;
1291 	 */
1292 	tlck = txLock(tid, ipimap, mp, tlckINODE | tlckFREE);
1293 	pxdlock = (struct pxd_lock *) & tlck->lock;
1294 	pxdlock->flag = mlckFREEPXD;
1295 	pxdlock->pxd = freepxd;
1296 	pxdlock->index = 1;
1297 
1298 	write_metapage(mp);
1299 
1300 	iplist[0] = ipimap;
1301 
1302 	/*
1303 	 * logredo needs the IAG number and IAG extent index in order
1304 	 * to ensure that the IMap is consistent.  The least disruptive
1305 	 * way to pass these values through  to the transaction manager
1306 	 * is in the iplist array.
1307 	 *
1308 	 * It's not pretty, but it works.
1309 	 */
1310 	iplist[1] = (struct inode *) (size_t)iagno;
1311 	iplist[2] = (struct inode *) (size_t)extno;
1312 
1313 	rc = txCommit(tid, 1, &iplist[0], COMMIT_FORCE);
1314 
1315 	txEnd(tid);
1316 	up(&JFS_IP(ipimap)->commit_sem);
1317 
1318 	/* unlock the AG inode map information */
1319 	AG_UNLOCK(imap, agno);
1320 
1321 	return (0);
1322 
1323       error_out:
1324 	IREAD_UNLOCK(ipimap);
1325 
1326 	if (amp)
1327 		release_metapage(amp);
1328 	if (bmp)
1329 		release_metapage(bmp);
1330 	if (cmp)
1331 		release_metapage(cmp);
1332 	if (dmp)
1333 		release_metapage(dmp);
1334 
1335 	AG_UNLOCK(imap, agno);
1336 
1337 	release_metapage(mp);
1338 
1339 	return (rc);
1340 }
1341 
1342 /*
1343  * There are several places in the diAlloc* routines where we initialize
1344  * the inode.
1345  */
1346 static inline void
1347 diInitInode(struct inode *ip, int iagno, int ino, int extno, struct iag * iagp)
1348 {
1349 	struct jfs_sb_info *sbi = JFS_SBI(ip->i_sb);
1350 	struct jfs_inode_info *jfs_ip = JFS_IP(ip);
1351 
1352 	ip->i_ino = (iagno << L2INOSPERIAG) + ino;
1353 	DBG_DIALLOC(JFS_IP(ipimap)->i_imap, ip->i_ino);
1354 	jfs_ip->ixpxd = iagp->inoext[extno];
1355 	jfs_ip->agno = BLKTOAG(le64_to_cpu(iagp->agstart), sbi);
1356 	jfs_ip->active_ag = -1;
1357 }
1358 
1359 
1360 /*
1361  * NAME:        diAlloc(pip,dir,ip)
1362  *
1363  * FUNCTION:    allocate a disk inode from the inode working map
1364  *		for a fileset or aggregate.
1365  *
1366  * PARAMETERS:
1367  *      pip  	- pointer to incore inode for the parent inode.
1368  *      dir  	- TRUE if the new disk inode is for a directory.
1369  *      ip  	- pointer to a new inode
1370  *
1371  * RETURN VALUES:
1372  *      0       - success.
1373  *      -ENOSPC	- insufficient disk resources.
1374  *      -EIO  	- i/o error.
1375  */
1376 int diAlloc(struct inode *pip, boolean_t dir, struct inode *ip)
1377 {
1378 	int rc, ino, iagno, addext, extno, bitno, sword;
1379 	int nwords, rem, i, agno;
1380 	u32 mask, inosmap, extsmap;
1381 	struct inode *ipimap;
1382 	struct metapage *mp;
1383 	ino_t inum;
1384 	struct iag *iagp;
1385 	struct inomap *imap;
1386 
1387 	/* get the pointers to the inode map inode and the
1388 	 * corresponding imap control structure.
1389 	 */
1390 	ipimap = JFS_SBI(pip->i_sb)->ipimap;
1391 	imap = JFS_IP(ipimap)->i_imap;
1392 	JFS_IP(ip)->ipimap = ipimap;
1393 	JFS_IP(ip)->fileset = FILESYSTEM_I;
1394 
1395 	/* for a directory, the allocation policy is to start
1396 	 * at the ag level using the preferred ag.
1397 	 */
1398 	if (dir == TRUE) {
1399 		agno = dbNextAG(JFS_SBI(pip->i_sb)->ipbmap);
1400 		AG_LOCK(imap, agno);
1401 		goto tryag;
1402 	}
1403 
1404 	/* for files, the policy starts off by trying to allocate from
1405 	 * the same iag containing the parent disk inode:
1406 	 * try to allocate the new disk inode close to the parent disk
1407 	 * inode, using parent disk inode number + 1 as the allocation
1408 	 * hint.  (we use a left-to-right policy to attempt to avoid
1409 	 * moving backward on the disk.)  compute the hint within the
1410 	 * file system and the iag.
1411 	 */
1412 
1413 	/* get the ag number of this iag */
1414 	agno = JFS_IP(pip)->agno;
1415 
1416 	if (atomic_read(&JFS_SBI(pip->i_sb)->bmap->db_active[agno])) {
1417 		/*
1418 		 * There is an open file actively growing.  We want to
1419 		 * allocate new inodes from a different ag to avoid
1420 		 * fragmentation problems.
1421 		 */
1422 		agno = dbNextAG(JFS_SBI(pip->i_sb)->ipbmap);
1423 		AG_LOCK(imap, agno);
1424 		goto tryag;
1425 	}
1426 
1427 	inum = pip->i_ino + 1;
1428 	ino = inum & (INOSPERIAG - 1);
1429 
1430 	/* back off the the hint if it is outside of the iag */
1431 	if (ino == 0)
1432 		inum = pip->i_ino;
1433 
1434 	/* lock the AG inode map information */
1435 	AG_LOCK(imap, agno);
1436 
1437 	/* Get read lock on imap inode */
1438 	IREAD_LOCK(ipimap);
1439 
1440 	/* get the iag number and read the iag */
1441 	iagno = INOTOIAG(inum);
1442 	if ((rc = diIAGRead(imap, iagno, &mp))) {
1443 		IREAD_UNLOCK(ipimap);
1444 		AG_UNLOCK(imap, agno);
1445 		return (rc);
1446 	}
1447 	iagp = (struct iag *) mp->data;
1448 
1449 	/* determine if new inode extent is allowed to be added to the iag.
1450 	 * new inode extent can be added to the iag if the ag
1451 	 * has less than 32 free disk inodes and the iag has free extents.
1452 	 */
1453 	addext = (imap->im_agctl[agno].numfree < 32 && iagp->nfreeexts);
1454 
1455 	/*
1456 	 *      try to allocate from the IAG
1457 	 */
1458 	/* check if the inode may be allocated from the iag
1459 	 * (i.e. the inode has free inodes or new extent can be added).
1460 	 */
1461 	if (iagp->nfreeinos || addext) {
1462 		/* determine the extent number of the hint.
1463 		 */
1464 		extno = ino >> L2INOSPEREXT;
1465 
1466 		/* check if the extent containing the hint has backed
1467 		 * inodes.  if so, try to allocate within this extent.
1468 		 */
1469 		if (addressPXD(&iagp->inoext[extno])) {
1470 			bitno = ino & (INOSPEREXT - 1);
1471 			if ((bitno =
1472 			     diFindFree(le32_to_cpu(iagp->wmap[extno]),
1473 					bitno))
1474 			    < INOSPEREXT) {
1475 				ino = (extno << L2INOSPEREXT) + bitno;
1476 
1477 				/* a free inode (bit) was found within this
1478 				 * extent, so allocate it.
1479 				 */
1480 				rc = diAllocBit(imap, iagp, ino);
1481 				IREAD_UNLOCK(ipimap);
1482 				if (rc) {
1483 					assert(rc == -EIO);
1484 				} else {
1485 					/* set the results of the allocation
1486 					 * and write the iag.
1487 					 */
1488 					diInitInode(ip, iagno, ino, extno,
1489 						    iagp);
1490 					mark_metapage_dirty(mp);
1491 				}
1492 				release_metapage(mp);
1493 
1494 				/* free the AG lock and return.
1495 				 */
1496 				AG_UNLOCK(imap, agno);
1497 				return (rc);
1498 			}
1499 
1500 			if (!addext)
1501 				extno =
1502 				    (extno ==
1503 				     EXTSPERIAG - 1) ? 0 : extno + 1;
1504 		}
1505 
1506 		/*
1507 		 * no free inodes within the extent containing the hint.
1508 		 *
1509 		 * try to allocate from the backed extents following
1510 		 * hint or, if appropriate (i.e. addext is true), allocate
1511 		 * an extent of free inodes at or following the extent
1512 		 * containing the hint.
1513 		 *
1514 		 * the free inode and free extent summary maps are used
1515 		 * here, so determine the starting summary map position
1516 		 * and the number of words we'll have to examine.  again,
1517 		 * the approach is to allocate following the hint, so we
1518 		 * might have to initially ignore prior bits of the summary
1519 		 * map that represent extents prior to the extent containing
1520 		 * the hint and later revisit these bits.
1521 		 */
1522 		bitno = extno & (EXTSPERSUM - 1);
1523 		nwords = (bitno == 0) ? SMAPSZ : SMAPSZ + 1;
1524 		sword = extno >> L2EXTSPERSUM;
1525 
1526 		/* mask any prior bits for the starting words of the
1527 		 * summary map.
1528 		 */
1529 		mask = ONES << (EXTSPERSUM - bitno);
1530 		inosmap = le32_to_cpu(iagp->inosmap[sword]) | mask;
1531 		extsmap = le32_to_cpu(iagp->extsmap[sword]) | mask;
1532 
1533 		/* scan the free inode and free extent summary maps for
1534 		 * free resources.
1535 		 */
1536 		for (i = 0; i < nwords; i++) {
1537 			/* check if this word of the free inode summary
1538 			 * map describes an extent with free inodes.
1539 			 */
1540 			if (~inosmap) {
1541 				/* an extent with free inodes has been
1542 				 * found. determine the extent number
1543 				 * and the inode number within the extent.
1544 				 */
1545 				rem = diFindFree(inosmap, 0);
1546 				extno = (sword << L2EXTSPERSUM) + rem;
1547 				rem = diFindFree(le32_to_cpu(iagp->wmap[extno]),
1548 						 0);
1549 				if (rem >= INOSPEREXT) {
1550 					IREAD_UNLOCK(ipimap);
1551 					release_metapage(mp);
1552 					AG_UNLOCK(imap, agno);
1553 					jfs_error(ip->i_sb,
1554 						  "diAlloc: can't find free bit "
1555 						  "in wmap");
1556 					return EIO;
1557 				}
1558 
1559 				/* determine the inode number within the
1560 				 * iag and allocate the inode from the
1561 				 * map.
1562 				 */
1563 				ino = (extno << L2INOSPEREXT) + rem;
1564 				rc = diAllocBit(imap, iagp, ino);
1565 				IREAD_UNLOCK(ipimap);
1566 				if (rc)
1567 					assert(rc == -EIO);
1568 				else {
1569 					/* set the results of the allocation
1570 					 * and write the iag.
1571 					 */
1572 					diInitInode(ip, iagno, ino, extno,
1573 						    iagp);
1574 					mark_metapage_dirty(mp);
1575 				}
1576 				release_metapage(mp);
1577 
1578 				/* free the AG lock and return.
1579 				 */
1580 				AG_UNLOCK(imap, agno);
1581 				return (rc);
1582 
1583 			}
1584 
1585 			/* check if we may allocate an extent of free
1586 			 * inodes and whether this word of the free
1587 			 * extents summary map describes a free extent.
1588 			 */
1589 			if (addext && ~extsmap) {
1590 				/* a free extent has been found.  determine
1591 				 * the extent number.
1592 				 */
1593 				rem = diFindFree(extsmap, 0);
1594 				extno = (sword << L2EXTSPERSUM) + rem;
1595 
1596 				/* allocate an extent of free inodes.
1597 				 */
1598 				if ((rc = diNewExt(imap, iagp, extno))) {
1599 					/* if there is no disk space for a
1600 					 * new extent, try to allocate the
1601 					 * disk inode from somewhere else.
1602 					 */
1603 					if (rc == -ENOSPC)
1604 						break;
1605 
1606 					assert(rc == -EIO);
1607 				} else {
1608 					/* set the results of the allocation
1609 					 * and write the iag.
1610 					 */
1611 					diInitInode(ip, iagno,
1612 						    extno << L2INOSPEREXT,
1613 						    extno, iagp);
1614 					mark_metapage_dirty(mp);
1615 				}
1616 				release_metapage(mp);
1617 				/* free the imap inode & the AG lock & return.
1618 				 */
1619 				IREAD_UNLOCK(ipimap);
1620 				AG_UNLOCK(imap, agno);
1621 				return (rc);
1622 			}
1623 
1624 			/* move on to the next set of summary map words.
1625 			 */
1626 			sword = (sword == SMAPSZ - 1) ? 0 : sword + 1;
1627 			inosmap = le32_to_cpu(iagp->inosmap[sword]);
1628 			extsmap = le32_to_cpu(iagp->extsmap[sword]);
1629 		}
1630 	}
1631 	/* unlock imap inode */
1632 	IREAD_UNLOCK(ipimap);
1633 
1634 	/* nothing doing in this iag, so release it. */
1635 	release_metapage(mp);
1636 
1637       tryag:
1638 	/*
1639 	 * try to allocate anywhere within the same AG as the parent inode.
1640 	 */
1641 	rc = diAllocAG(imap, agno, dir, ip);
1642 
1643 	AG_UNLOCK(imap, agno);
1644 
1645 	if (rc != -ENOSPC)
1646 		return (rc);
1647 
1648 	/*
1649 	 * try to allocate in any AG.
1650 	 */
1651 	return (diAllocAny(imap, agno, dir, ip));
1652 }
1653 
1654 
1655 /*
1656  * NAME:        diAllocAG(imap,agno,dir,ip)
1657  *
1658  * FUNCTION:    allocate a disk inode from the allocation group.
1659  *
1660  *		this routine first determines if a new extent of free
1661  *		inodes should be added for the allocation group, with
1662  *		the current request satisfied from this extent. if this
1663  *		is the case, an attempt will be made to do just that.  if
1664  *		this attempt fails or it has been determined that a new
1665  *		extent should not be added, an attempt is made to satisfy
1666  *		the request by allocating an existing (backed) free inode
1667  *		from the allocation group.
1668  *
1669  * PRE CONDITION: Already have the AG lock for this AG.
1670  *
1671  * PARAMETERS:
1672  *      imap  	- pointer to inode map control structure.
1673  *      agno  	- allocation group to allocate from.
1674  *      dir  	- TRUE if the new disk inode is for a directory.
1675  *      ip  	- pointer to the new inode to be filled in on successful return
1676  *		  with the disk inode number allocated, its extent address
1677  *		  and the start of the ag.
1678  *
1679  * RETURN VALUES:
1680  *      0       - success.
1681  *      -ENOSPC	- insufficient disk resources.
1682  *      -EIO  	- i/o error.
1683  */
1684 static int
1685 diAllocAG(struct inomap * imap, int agno, boolean_t dir, struct inode *ip)
1686 {
1687 	int rc, addext, numfree, numinos;
1688 
1689 	/* get the number of free and the number of backed disk
1690 	 * inodes currently within the ag.
1691 	 */
1692 	numfree = imap->im_agctl[agno].numfree;
1693 	numinos = imap->im_agctl[agno].numinos;
1694 
1695 	if (numfree > numinos) {
1696 		jfs_error(ip->i_sb, "diAllocAG: numfree > numinos");
1697 		return -EIO;
1698 	}
1699 
1700 	/* determine if we should allocate a new extent of free inodes
1701 	 * within the ag: for directory inodes, add a new extent
1702 	 * if there are a small number of free inodes or number of free
1703 	 * inodes is a small percentage of the number of backed inodes.
1704 	 */
1705 	if (dir == TRUE)
1706 		addext = (numfree < 64 ||
1707 			  (numfree < 256
1708 			   && ((numfree * 100) / numinos) <= 20));
1709 	else
1710 		addext = (numfree == 0);
1711 
1712 	/*
1713 	 * try to allocate a new extent of free inodes.
1714 	 */
1715 	if (addext) {
1716 		/* if free space is not avaliable for this new extent, try
1717 		 * below to allocate a free and existing (already backed)
1718 		 * inode from the ag.
1719 		 */
1720 		if ((rc = diAllocExt(imap, agno, ip)) != -ENOSPC)
1721 			return (rc);
1722 	}
1723 
1724 	/*
1725 	 * try to allocate an existing free inode from the ag.
1726 	 */
1727 	return (diAllocIno(imap, agno, ip));
1728 }
1729 
1730 
1731 /*
1732  * NAME:        diAllocAny(imap,agno,dir,iap)
1733  *
1734  * FUNCTION:    allocate a disk inode from any other allocation group.
1735  *
1736  *		this routine is called when an allocation attempt within
1737  *		the primary allocation group has failed. if attempts to
1738  *		allocate an inode from any allocation group other than the
1739  *		specified primary group.
1740  *
1741  * PARAMETERS:
1742  *      imap  	- pointer to inode map control structure.
1743  *      agno  	- primary allocation group (to avoid).
1744  *      dir  	- TRUE if the new disk inode is for a directory.
1745  *      ip  	- pointer to a new inode to be filled in on successful return
1746  *		  with the disk inode number allocated, its extent address
1747  *		  and the start of the ag.
1748  *
1749  * RETURN VALUES:
1750  *      0       - success.
1751  *      -ENOSPC	- insufficient disk resources.
1752  *      -EIO  	- i/o error.
1753  */
1754 static int
1755 diAllocAny(struct inomap * imap, int agno, boolean_t dir, struct inode *ip)
1756 {
1757 	int ag, rc;
1758 	int maxag = JFS_SBI(imap->im_ipimap->i_sb)->bmap->db_maxag;
1759 
1760 
1761 	/* try to allocate from the ags following agno up to
1762 	 * the maximum ag number.
1763 	 */
1764 	for (ag = agno + 1; ag <= maxag; ag++) {
1765 		AG_LOCK(imap, ag);
1766 
1767 		rc = diAllocAG(imap, ag, dir, ip);
1768 
1769 		AG_UNLOCK(imap, ag);
1770 
1771 		if (rc != -ENOSPC)
1772 			return (rc);
1773 	}
1774 
1775 	/* try to allocate from the ags in front of agno.
1776 	 */
1777 	for (ag = 0; ag < agno; ag++) {
1778 		AG_LOCK(imap, ag);
1779 
1780 		rc = diAllocAG(imap, ag, dir, ip);
1781 
1782 		AG_UNLOCK(imap, ag);
1783 
1784 		if (rc != -ENOSPC)
1785 			return (rc);
1786 	}
1787 
1788 	/* no free disk inodes.
1789 	 */
1790 	return -ENOSPC;
1791 }
1792 
1793 
1794 /*
1795  * NAME:        diAllocIno(imap,agno,ip)
1796  *
1797  * FUNCTION:    allocate a disk inode from the allocation group's free
1798  *		inode list, returning an error if this free list is
1799  *		empty (i.e. no iags on the list).
1800  *
1801  *		allocation occurs from the first iag on the list using
1802  *		the iag's free inode summary map to find the leftmost
1803  *		free inode in the iag.
1804  *
1805  * PRE CONDITION: Already have AG lock for this AG.
1806  *
1807  * PARAMETERS:
1808  *      imap  	- pointer to inode map control structure.
1809  *      agno  	- allocation group.
1810  *      ip  	- pointer to new inode to be filled in on successful return
1811  *		  with the disk inode number allocated, its extent address
1812  *		  and the start of the ag.
1813  *
1814  * RETURN VALUES:
1815  *      0       - success.
1816  *      -ENOSPC	- insufficient disk resources.
1817  *      -EIO  	- i/o error.
1818  */
1819 static int diAllocIno(struct inomap * imap, int agno, struct inode *ip)
1820 {
1821 	int iagno, ino, rc, rem, extno, sword;
1822 	struct metapage *mp;
1823 	struct iag *iagp;
1824 
1825 	/* check if there are iags on the ag's free inode list.
1826 	 */
1827 	if ((iagno = imap->im_agctl[agno].inofree) < 0)
1828 		return -ENOSPC;
1829 
1830 	/* obtain read lock on imap inode */
1831 	IREAD_LOCK(imap->im_ipimap);
1832 
1833 	/* read the iag at the head of the list.
1834 	 */
1835 	if ((rc = diIAGRead(imap, iagno, &mp))) {
1836 		IREAD_UNLOCK(imap->im_ipimap);
1837 		return (rc);
1838 	}
1839 	iagp = (struct iag *) mp->data;
1840 
1841 	/* better be free inodes in this iag if it is on the
1842 	 * list.
1843 	 */
1844 	if (!iagp->nfreeinos) {
1845 		IREAD_UNLOCK(imap->im_ipimap);
1846 		release_metapage(mp);
1847 		jfs_error(ip->i_sb,
1848 			  "diAllocIno: nfreeinos = 0, but iag on freelist");
1849 		return -EIO;
1850 	}
1851 
1852 	/* scan the free inode summary map to find an extent
1853 	 * with free inodes.
1854 	 */
1855 	for (sword = 0;; sword++) {
1856 		if (sword >= SMAPSZ) {
1857 			IREAD_UNLOCK(imap->im_ipimap);
1858 			release_metapage(mp);
1859 			jfs_error(ip->i_sb,
1860 				  "diAllocIno: free inode not found in summary map");
1861 			return -EIO;
1862 		}
1863 
1864 		if (~iagp->inosmap[sword])
1865 			break;
1866 	}
1867 
1868 	/* found a extent with free inodes. determine
1869 	 * the extent number.
1870 	 */
1871 	rem = diFindFree(le32_to_cpu(iagp->inosmap[sword]), 0);
1872 	if (rem >= EXTSPERSUM) {
1873 		IREAD_UNLOCK(imap->im_ipimap);
1874 		release_metapage(mp);
1875 		jfs_error(ip->i_sb, "diAllocIno: no free extent found");
1876 		return -EIO;
1877 	}
1878 	extno = (sword << L2EXTSPERSUM) + rem;
1879 
1880 	/* find the first free inode in the extent.
1881 	 */
1882 	rem = diFindFree(le32_to_cpu(iagp->wmap[extno]), 0);
1883 	if (rem >= INOSPEREXT) {
1884 		IREAD_UNLOCK(imap->im_ipimap);
1885 		release_metapage(mp);
1886 		jfs_error(ip->i_sb, "diAllocIno: free inode not found");
1887 		return -EIO;
1888 	}
1889 
1890 	/* compute the inode number within the iag.
1891 	 */
1892 	ino = (extno << L2INOSPEREXT) + rem;
1893 
1894 	/* allocate the inode.
1895 	 */
1896 	rc = diAllocBit(imap, iagp, ino);
1897 	IREAD_UNLOCK(imap->im_ipimap);
1898 	if (rc) {
1899 		release_metapage(mp);
1900 		return (rc);
1901 	}
1902 
1903 	/* set the results of the allocation and write the iag.
1904 	 */
1905 	diInitInode(ip, iagno, ino, extno, iagp);
1906 	write_metapage(mp);
1907 
1908 	return (0);
1909 }
1910 
1911 
1912 /*
1913  * NAME:        diAllocExt(imap,agno,ip)
1914  *
1915  * FUNCTION:   	add a new extent of free inodes to an iag, allocating
1916  *	       	an inode from this extent to satisfy the current allocation
1917  *	       	request.
1918  *
1919  *		this routine first tries to find an existing iag with free
1920  *		extents through the ag free extent list.  if list is not
1921  *		empty, the head of the list will be selected as the home
1922  *		of the new extent of free inodes.  otherwise (the list is
1923  *		empty), a new iag will be allocated for the ag to contain
1924  *		the extent.
1925  *
1926  *		once an iag has been selected, the free extent summary map
1927  *		is used to locate a free extent within the iag and diNewExt()
1928  *		is called to initialize the extent, with initialization
1929  *		including the allocation of the first inode of the extent
1930  *		for the purpose of satisfying this request.
1931  *
1932  * PARAMETERS:
1933  *      imap  	- pointer to inode map control structure.
1934  *      agno  	- allocation group number.
1935  *      ip  	- pointer to new inode to be filled in on successful return
1936  *		  with the disk inode number allocated, its extent address
1937  *		  and the start of the ag.
1938  *
1939  * RETURN VALUES:
1940  *      0       - success.
1941  *      -ENOSPC	- insufficient disk resources.
1942  *      -EIO  	- i/o error.
1943  */
1944 static int diAllocExt(struct inomap * imap, int agno, struct inode *ip)
1945 {
1946 	int rem, iagno, sword, extno, rc;
1947 	struct metapage *mp;
1948 	struct iag *iagp;
1949 
1950 	/* check if the ag has any iags with free extents.  if not,
1951 	 * allocate a new iag for the ag.
1952 	 */
1953 	if ((iagno = imap->im_agctl[agno].extfree) < 0) {
1954 		/* If successful, diNewIAG will obtain the read lock on the
1955 		 * imap inode.
1956 		 */
1957 		if ((rc = diNewIAG(imap, &iagno, agno, &mp))) {
1958 			return (rc);
1959 		}
1960 		iagp = (struct iag *) mp->data;
1961 
1962 		/* set the ag number if this a brand new iag
1963 		 */
1964 		iagp->agstart =
1965 		    cpu_to_le64(AGTOBLK(agno, imap->im_ipimap));
1966 	} else {
1967 		/* read the iag.
1968 		 */
1969 		IREAD_LOCK(imap->im_ipimap);
1970 		if ((rc = diIAGRead(imap, iagno, &mp))) {
1971 			IREAD_UNLOCK(imap->im_ipimap);
1972 			jfs_error(ip->i_sb, "diAllocExt: error reading iag");
1973 			return rc;
1974 		}
1975 		iagp = (struct iag *) mp->data;
1976 	}
1977 
1978 	/* using the free extent summary map, find a free extent.
1979 	 */
1980 	for (sword = 0;; sword++) {
1981 		if (sword >= SMAPSZ) {
1982 			release_metapage(mp);
1983 			IREAD_UNLOCK(imap->im_ipimap);
1984 			jfs_error(ip->i_sb,
1985 				  "diAllocExt: free ext summary map not found");
1986 			return -EIO;
1987 		}
1988 		if (~iagp->extsmap[sword])
1989 			break;
1990 	}
1991 
1992 	/* determine the extent number of the free extent.
1993 	 */
1994 	rem = diFindFree(le32_to_cpu(iagp->extsmap[sword]), 0);
1995 	if (rem >= EXTSPERSUM) {
1996 		release_metapage(mp);
1997 		IREAD_UNLOCK(imap->im_ipimap);
1998 		jfs_error(ip->i_sb, "diAllocExt: free extent not found");
1999 		return -EIO;
2000 	}
2001 	extno = (sword << L2EXTSPERSUM) + rem;
2002 
2003 	/* initialize the new extent.
2004 	 */
2005 	rc = diNewExt(imap, iagp, extno);
2006 	IREAD_UNLOCK(imap->im_ipimap);
2007 	if (rc) {
2008 		/* something bad happened.  if a new iag was allocated,
2009 		 * place it back on the inode map's iag free list, and
2010 		 * clear the ag number information.
2011 		 */
2012 		if (iagp->nfreeexts == cpu_to_le32(EXTSPERIAG)) {
2013 			IAGFREE_LOCK(imap);
2014 			iagp->iagfree = cpu_to_le32(imap->im_freeiag);
2015 			imap->im_freeiag = iagno;
2016 			IAGFREE_UNLOCK(imap);
2017 		}
2018 		write_metapage(mp);
2019 		return (rc);
2020 	}
2021 
2022 	/* set the results of the allocation and write the iag.
2023 	 */
2024 	diInitInode(ip, iagno, extno << L2INOSPEREXT, extno, iagp);
2025 
2026 	write_metapage(mp);
2027 
2028 	return (0);
2029 }
2030 
2031 
2032 /*
2033  * NAME:        diAllocBit(imap,iagp,ino)
2034  *
2035  * FUNCTION:   	allocate a backed inode from an iag.
2036  *
2037  *		this routine performs the mechanics of allocating a
2038  *		specified inode from a backed extent.
2039  *
2040  *		if the inode to be allocated represents the last free
2041  *		inode within the iag, the iag will be removed from the
2042  *		ag free inode list.
2043  *
2044  *		a careful update approach is used to provide consistency
2045  *		in the face of updates to multiple buffers.  under this
2046  *		approach, all required buffers are obtained before making
2047  *		any updates and are held all are updates are complete.
2048  *
2049  * PRE CONDITION: Already have buffer lock on iagp.  Already have AG lock on
2050  *	this AG.  Must have read lock on imap inode.
2051  *
2052  * PARAMETERS:
2053  *      imap  	- pointer to inode map control structure.
2054  *      iagp  	- pointer to iag.
2055  *      ino   	- inode number to be allocated within the iag.
2056  *
2057  * RETURN VALUES:
2058  *      0       - success.
2059  *      -ENOSPC	- insufficient disk resources.
2060  *      -EIO  	- i/o error.
2061  */
2062 static int diAllocBit(struct inomap * imap, struct iag * iagp, int ino)
2063 {
2064 	int extno, bitno, agno, sword, rc;
2065 	struct metapage *amp = NULL, *bmp = NULL;
2066 	struct iag *aiagp = NULL, *biagp = NULL;
2067 	u32 mask;
2068 
2069 	/* check if this is the last free inode within the iag.
2070 	 * if so, it will have to be removed from the ag free
2071 	 * inode list, so get the iags preceeding and following
2072 	 * it on the list.
2073 	 */
2074 	if (iagp->nfreeinos == cpu_to_le32(1)) {
2075 		if ((int) le32_to_cpu(iagp->inofreefwd) >= 0) {
2076 			if ((rc =
2077 			     diIAGRead(imap, le32_to_cpu(iagp->inofreefwd),
2078 				       &amp)))
2079 				return (rc);
2080 			aiagp = (struct iag *) amp->data;
2081 		}
2082 
2083 		if ((int) le32_to_cpu(iagp->inofreeback) >= 0) {
2084 			if ((rc =
2085 			     diIAGRead(imap,
2086 				       le32_to_cpu(iagp->inofreeback),
2087 				       &bmp))) {
2088 				if (amp)
2089 					release_metapage(amp);
2090 				return (rc);
2091 			}
2092 			biagp = (struct iag *) bmp->data;
2093 		}
2094 	}
2095 
2096 	/* get the ag number, extent number, inode number within
2097 	 * the extent.
2098 	 */
2099 	agno = BLKTOAG(le64_to_cpu(iagp->agstart), JFS_SBI(imap->im_ipimap->i_sb));
2100 	extno = ino >> L2INOSPEREXT;
2101 	bitno = ino & (INOSPEREXT - 1);
2102 
2103 	/* compute the mask for setting the map.
2104 	 */
2105 	mask = HIGHORDER >> bitno;
2106 
2107 	/* the inode should be free and backed.
2108 	 */
2109 	if (((le32_to_cpu(iagp->pmap[extno]) & mask) != 0) ||
2110 	    ((le32_to_cpu(iagp->wmap[extno]) & mask) != 0) ||
2111 	    (addressPXD(&iagp->inoext[extno]) == 0)) {
2112 		if (amp)
2113 			release_metapage(amp);
2114 		if (bmp)
2115 			release_metapage(bmp);
2116 
2117 		jfs_error(imap->im_ipimap->i_sb,
2118 			  "diAllocBit: iag inconsistent");
2119 		return -EIO;
2120 	}
2121 
2122 	/* mark the inode as allocated in the working map.
2123 	 */
2124 	iagp->wmap[extno] |= cpu_to_le32(mask);
2125 
2126 	/* check if all inodes within the extent are now
2127 	 * allocated.  if so, update the free inode summary
2128 	 * map to reflect this.
2129 	 */
2130 	if (iagp->wmap[extno] == cpu_to_le32(ONES)) {
2131 		sword = extno >> L2EXTSPERSUM;
2132 		bitno = extno & (EXTSPERSUM - 1);
2133 		iagp->inosmap[sword] |= cpu_to_le32(HIGHORDER >> bitno);
2134 	}
2135 
2136 	/* if this was the last free inode in the iag, remove the
2137 	 * iag from the ag free inode list.
2138 	 */
2139 	if (iagp->nfreeinos == cpu_to_le32(1)) {
2140 		if (amp) {
2141 			aiagp->inofreeback = iagp->inofreeback;
2142 			write_metapage(amp);
2143 		}
2144 
2145 		if (bmp) {
2146 			biagp->inofreefwd = iagp->inofreefwd;
2147 			write_metapage(bmp);
2148 		} else {
2149 			imap->im_agctl[agno].inofree =
2150 			    le32_to_cpu(iagp->inofreefwd);
2151 		}
2152 		iagp->inofreefwd = iagp->inofreeback = cpu_to_le32(-1);
2153 	}
2154 
2155 	/* update the free inode count at the iag, ag, inode
2156 	 * map levels.
2157 	 */
2158 	iagp->nfreeinos = cpu_to_le32(le32_to_cpu(iagp->nfreeinos) - 1);
2159 	imap->im_agctl[agno].numfree -= 1;
2160 	atomic_dec(&imap->im_numfree);
2161 
2162 	return (0);
2163 }
2164 
2165 
2166 /*
2167  * NAME:        diNewExt(imap,iagp,extno)
2168  *
2169  * FUNCTION:    initialize a new extent of inodes for an iag, allocating
2170  *	        the first inode of the extent for use for the current
2171  *	        allocation request.
2172  *
2173  *		disk resources are allocated for the new extent of inodes
2174  *		and the inodes themselves are initialized to reflect their
2175  *		existence within the extent (i.e. their inode numbers and
2176  *		inode extent addresses are set) and their initial state
2177  *		(mode and link count are set to zero).
2178  *
2179  *		if the iag is new, it is not yet on an ag extent free list
2180  *		but will now be placed on this list.
2181  *
2182  *		if the allocation of the new extent causes the iag to
2183  *		have no free extent, the iag will be removed from the
2184  *		ag extent free list.
2185  *
2186  *		if the iag has no free backed inodes, it will be placed
2187  *		on the ag free inode list, since the addition of the new
2188  *		extent will now cause it to have free inodes.
2189  *
2190  *		a careful update approach is used to provide consistency
2191  *		(i.e. list consistency) in the face of updates to multiple
2192  *		buffers.  under this approach, all required buffers are
2193  *		obtained before making any updates and are held until all
2194  *		updates are complete.
2195  *
2196  * PRE CONDITION: Already have buffer lock on iagp.  Already have AG lock on
2197  *	this AG.  Must have read lock on imap inode.
2198  *
2199  * PARAMETERS:
2200  *      imap  	- pointer to inode map control structure.
2201  *      iagp  	- pointer to iag.
2202  *      extno  	- extent number.
2203  *
2204  * RETURN VALUES:
2205  *      0       - success.
2206  *      -ENOSPC	- insufficient disk resources.
2207  *      -EIO  	- i/o error.
2208  */
2209 static int diNewExt(struct inomap * imap, struct iag * iagp, int extno)
2210 {
2211 	int agno, iagno, fwd, back, freei = 0, sword, rc;
2212 	struct iag *aiagp = NULL, *biagp = NULL, *ciagp = NULL;
2213 	struct metapage *amp, *bmp, *cmp, *dmp;
2214 	struct inode *ipimap;
2215 	s64 blkno, hint;
2216 	int i, j;
2217 	u32 mask;
2218 	ino_t ino;
2219 	struct dinode *dp;
2220 	struct jfs_sb_info *sbi;
2221 
2222 	/* better have free extents.
2223 	 */
2224 	if (!iagp->nfreeexts) {
2225 		jfs_error(imap->im_ipimap->i_sb, "diNewExt: no free extents");
2226 		return -EIO;
2227 	}
2228 
2229 	/* get the inode map inode.
2230 	 */
2231 	ipimap = imap->im_ipimap;
2232 	sbi = JFS_SBI(ipimap->i_sb);
2233 
2234 	amp = bmp = cmp = NULL;
2235 
2236 	/* get the ag and iag numbers for this iag.
2237 	 */
2238 	agno = BLKTOAG(le64_to_cpu(iagp->agstart), sbi);
2239 	iagno = le32_to_cpu(iagp->iagnum);
2240 
2241 	/* check if this is the last free extent within the
2242 	 * iag.  if so, the iag must be removed from the ag
2243 	 * free extent list, so get the iags preceeding and
2244 	 * following the iag on this list.
2245 	 */
2246 	if (iagp->nfreeexts == cpu_to_le32(1)) {
2247 		if ((fwd = le32_to_cpu(iagp->extfreefwd)) >= 0) {
2248 			if ((rc = diIAGRead(imap, fwd, &amp)))
2249 				return (rc);
2250 			aiagp = (struct iag *) amp->data;
2251 		}
2252 
2253 		if ((back = le32_to_cpu(iagp->extfreeback)) >= 0) {
2254 			if ((rc = diIAGRead(imap, back, &bmp)))
2255 				goto error_out;
2256 			biagp = (struct iag *) bmp->data;
2257 		}
2258 	} else {
2259 		/* the iag has free extents.  if all extents are free
2260 		 * (as is the case for a newly allocated iag), the iag
2261 		 * must be added to the ag free extent list, so get
2262 		 * the iag at the head of the list in preparation for
2263 		 * adding this iag to this list.
2264 		 */
2265 		fwd = back = -1;
2266 		if (iagp->nfreeexts == cpu_to_le32(EXTSPERIAG)) {
2267 			if ((fwd = imap->im_agctl[agno].extfree) >= 0) {
2268 				if ((rc = diIAGRead(imap, fwd, &amp)))
2269 					goto error_out;
2270 				aiagp = (struct iag *) amp->data;
2271 			}
2272 		}
2273 	}
2274 
2275 	/* check if the iag has no free inodes.  if so, the iag
2276 	 * will have to be added to the ag free inode list, so get
2277 	 * the iag at the head of the list in preparation for
2278 	 * adding this iag to this list.  in doing this, we must
2279 	 * check if we already have the iag at the head of
2280 	 * the list in hand.
2281 	 */
2282 	if (iagp->nfreeinos == 0) {
2283 		freei = imap->im_agctl[agno].inofree;
2284 
2285 		if (freei >= 0) {
2286 			if (freei == fwd) {
2287 				ciagp = aiagp;
2288 			} else if (freei == back) {
2289 				ciagp = biagp;
2290 			} else {
2291 				if ((rc = diIAGRead(imap, freei, &cmp)))
2292 					goto error_out;
2293 				ciagp = (struct iag *) cmp->data;
2294 			}
2295 			if (ciagp == NULL) {
2296 				jfs_error(imap->im_ipimap->i_sb,
2297 					  "diNewExt: ciagp == NULL");
2298 				rc = -EIO;
2299 				goto error_out;
2300 			}
2301 		}
2302 	}
2303 
2304 	/* allocate disk space for the inode extent.
2305 	 */
2306 	if ((extno == 0) || (addressPXD(&iagp->inoext[extno - 1]) == 0))
2307 		hint = ((s64) agno << sbi->bmap->db_agl2size) - 1;
2308 	else
2309 		hint = addressPXD(&iagp->inoext[extno - 1]) +
2310 		    lengthPXD(&iagp->inoext[extno - 1]) - 1;
2311 
2312 	if ((rc = dbAlloc(ipimap, hint, (s64) imap->im_nbperiext, &blkno)))
2313 		goto error_out;
2314 
2315 	/* compute the inode number of the first inode within the
2316 	 * extent.
2317 	 */
2318 	ino = (iagno << L2INOSPERIAG) + (extno << L2INOSPEREXT);
2319 
2320 	/* initialize the inodes within the newly allocated extent a
2321 	 * page at a time.
2322 	 */
2323 	for (i = 0; i < imap->im_nbperiext; i += sbi->nbperpage) {
2324 		/* get a buffer for this page of disk inodes.
2325 		 */
2326 		dmp = get_metapage(ipimap, blkno + i, PSIZE, 1);
2327 		if (dmp == NULL) {
2328 			rc = -EIO;
2329 			goto error_out;
2330 		}
2331 		dp = (struct dinode *) dmp->data;
2332 
2333 		/* initialize the inode number, mode, link count and
2334 		 * inode extent address.
2335 		 */
2336 		for (j = 0; j < INOSPERPAGE; j++, dp++, ino++) {
2337 			dp->di_inostamp = cpu_to_le32(sbi->inostamp);
2338 			dp->di_number = cpu_to_le32(ino);
2339 			dp->di_fileset = cpu_to_le32(FILESYSTEM_I);
2340 			dp->di_mode = 0;
2341 			dp->di_nlink = 0;
2342 			PXDaddress(&(dp->di_ixpxd), blkno);
2343 			PXDlength(&(dp->di_ixpxd), imap->im_nbperiext);
2344 		}
2345 		write_metapage(dmp);
2346 	}
2347 
2348 	/* if this is the last free extent within the iag, remove the
2349 	 * iag from the ag free extent list.
2350 	 */
2351 	if (iagp->nfreeexts == cpu_to_le32(1)) {
2352 		if (fwd >= 0)
2353 			aiagp->extfreeback = iagp->extfreeback;
2354 
2355 		if (back >= 0)
2356 			biagp->extfreefwd = iagp->extfreefwd;
2357 		else
2358 			imap->im_agctl[agno].extfree =
2359 			    le32_to_cpu(iagp->extfreefwd);
2360 
2361 		iagp->extfreefwd = iagp->extfreeback = cpu_to_le32(-1);
2362 	} else {
2363 		/* if the iag has all free extents (newly allocated iag),
2364 		 * add the iag to the ag free extent list.
2365 		 */
2366 		if (iagp->nfreeexts == cpu_to_le32(EXTSPERIAG)) {
2367 			if (fwd >= 0)
2368 				aiagp->extfreeback = cpu_to_le32(iagno);
2369 
2370 			iagp->extfreefwd = cpu_to_le32(fwd);
2371 			iagp->extfreeback = cpu_to_le32(-1);
2372 			imap->im_agctl[agno].extfree = iagno;
2373 		}
2374 	}
2375 
2376 	/* if the iag has no free inodes, add the iag to the
2377 	 * ag free inode list.
2378 	 */
2379 	if (iagp->nfreeinos == 0) {
2380 		if (freei >= 0)
2381 			ciagp->inofreeback = cpu_to_le32(iagno);
2382 
2383 		iagp->inofreefwd =
2384 		    cpu_to_le32(imap->im_agctl[agno].inofree);
2385 		iagp->inofreeback = cpu_to_le32(-1);
2386 		imap->im_agctl[agno].inofree = iagno;
2387 	}
2388 
2389 	/* initialize the extent descriptor of the extent. */
2390 	PXDlength(&iagp->inoext[extno], imap->im_nbperiext);
2391 	PXDaddress(&iagp->inoext[extno], blkno);
2392 
2393 	/* initialize the working and persistent map of the extent.
2394 	 * the working map will be initialized such that
2395 	 * it indicates the first inode of the extent is allocated.
2396 	 */
2397 	iagp->wmap[extno] = cpu_to_le32(HIGHORDER);
2398 	iagp->pmap[extno] = 0;
2399 
2400 	/* update the free inode and free extent summary maps
2401 	 * for the extent to indicate the extent has free inodes
2402 	 * and no longer represents a free extent.
2403 	 */
2404 	sword = extno >> L2EXTSPERSUM;
2405 	mask = HIGHORDER >> (extno & (EXTSPERSUM - 1));
2406 	iagp->extsmap[sword] |= cpu_to_le32(mask);
2407 	iagp->inosmap[sword] &= cpu_to_le32(~mask);
2408 
2409 	/* update the free inode and free extent counts for the
2410 	 * iag.
2411 	 */
2412 	iagp->nfreeinos = cpu_to_le32(le32_to_cpu(iagp->nfreeinos) +
2413 				      (INOSPEREXT - 1));
2414 	iagp->nfreeexts = cpu_to_le32(le32_to_cpu(iagp->nfreeexts) - 1);
2415 
2416 	/* update the free and backed inode counts for the ag.
2417 	 */
2418 	imap->im_agctl[agno].numfree += (INOSPEREXT - 1);
2419 	imap->im_agctl[agno].numinos += INOSPEREXT;
2420 
2421 	/* update the free and backed inode counts for the inode map.
2422 	 */
2423 	atomic_add(INOSPEREXT - 1, &imap->im_numfree);
2424 	atomic_add(INOSPEREXT, &imap->im_numinos);
2425 
2426 	/* write the iags.
2427 	 */
2428 	if (amp)
2429 		write_metapage(amp);
2430 	if (bmp)
2431 		write_metapage(bmp);
2432 	if (cmp)
2433 		write_metapage(cmp);
2434 
2435 	return (0);
2436 
2437       error_out:
2438 
2439 	/* release the iags.
2440 	 */
2441 	if (amp)
2442 		release_metapage(amp);
2443 	if (bmp)
2444 		release_metapage(bmp);
2445 	if (cmp)
2446 		release_metapage(cmp);
2447 
2448 	return (rc);
2449 }
2450 
2451 
2452 /*
2453  * NAME:        diNewIAG(imap,iagnop,agno)
2454  *
2455  * FUNCTION:   	allocate a new iag for an allocation group.
2456  *
2457  *		first tries to allocate the iag from the inode map
2458  *		iagfree list:
2459  *		if the list has free iags, the head of the list is removed
2460  *		and returned to satisfy the request.
2461  *		if the inode map's iag free list is empty, the inode map
2462  *		is extended to hold a new iag. this new iag is initialized
2463  *		and returned to satisfy the request.
2464  *
2465  * PARAMETERS:
2466  *      imap  	- pointer to inode map control structure.
2467  *      iagnop 	- pointer to an iag number set with the number of the
2468  *		  newly allocated iag upon successful return.
2469  *      agno  	- allocation group number.
2470  *	bpp	- Buffer pointer to be filled in with new IAG's buffer
2471  *
2472  * RETURN VALUES:
2473  *      0       - success.
2474  *      -ENOSPC	- insufficient disk resources.
2475  *      -EIO  	- i/o error.
2476  *
2477  * serialization:
2478  *	AG lock held on entry/exit;
2479  *	write lock on the map is held inside;
2480  *	read lock on the map is held on successful completion;
2481  *
2482  * note: new iag transaction:
2483  * . synchronously write iag;
2484  * . write log of xtree and inode  of imap;
2485  * . commit;
2486  * . synchronous write of xtree (right to left, bottom to top);
2487  * . at start of logredo(): init in-memory imap with one additional iag page;
2488  * . at end of logredo(): re-read imap inode to determine
2489  *   new imap size;
2490  */
2491 static int
2492 diNewIAG(struct inomap * imap, int *iagnop, int agno, struct metapage ** mpp)
2493 {
2494 	int rc;
2495 	int iagno, i, xlen;
2496 	struct inode *ipimap;
2497 	struct super_block *sb;
2498 	struct jfs_sb_info *sbi;
2499 	struct metapage *mp;
2500 	struct iag *iagp;
2501 	s64 xaddr = 0;
2502 	s64 blkno;
2503 	tid_t tid;
2504 #ifdef _STILL_TO_PORT
2505 	xad_t xad;
2506 #endif				/*  _STILL_TO_PORT */
2507 	struct inode *iplist[1];
2508 
2509 	/* pick up pointers to the inode map and mount inodes */
2510 	ipimap = imap->im_ipimap;
2511 	sb = ipimap->i_sb;
2512 	sbi = JFS_SBI(sb);
2513 
2514 	/* acquire the free iag lock */
2515 	IAGFREE_LOCK(imap);
2516 
2517 	/* if there are any iags on the inode map free iag list,
2518 	 * allocate the iag from the head of the list.
2519 	 */
2520 	if (imap->im_freeiag >= 0) {
2521 		/* pick up the iag number at the head of the list */
2522 		iagno = imap->im_freeiag;
2523 
2524 		/* determine the logical block number of the iag */
2525 		blkno = IAGTOLBLK(iagno, sbi->l2nbperpage);
2526 	} else {
2527 		/* no free iags. the inode map will have to be extented
2528 		 * to include a new iag.
2529 		 */
2530 
2531 		/* acquire inode map lock */
2532 		IWRITE_LOCK(ipimap);
2533 
2534 		if (ipimap->i_size >> L2PSIZE != imap->im_nextiag + 1) {
2535 			IWRITE_UNLOCK(ipimap);
2536 			IAGFREE_UNLOCK(imap);
2537 			jfs_error(imap->im_ipimap->i_sb,
2538 				  "diNewIAG: ipimap->i_size is wrong");
2539 			return -EIO;
2540 		}
2541 
2542 
2543 		/* get the next avaliable iag number */
2544 		iagno = imap->im_nextiag;
2545 
2546 		/* make sure that we have not exceeded the maximum inode
2547 		 * number limit.
2548 		 */
2549 		if (iagno > (MAXIAGS - 1)) {
2550 			/* release the inode map lock */
2551 			IWRITE_UNLOCK(ipimap);
2552 
2553 			rc = -ENOSPC;
2554 			goto out;
2555 		}
2556 
2557 		/*
2558 		 * synchronously append new iag page.
2559 		 */
2560 		/* determine the logical address of iag page to append */
2561 		blkno = IAGTOLBLK(iagno, sbi->l2nbperpage);
2562 
2563 		/* Allocate extent for new iag page */
2564 		xlen = sbi->nbperpage;
2565 		if ((rc = dbAlloc(ipimap, 0, (s64) xlen, &xaddr))) {
2566 			/* release the inode map lock */
2567 			IWRITE_UNLOCK(ipimap);
2568 
2569 			goto out;
2570 		}
2571 
2572 		/*
2573 		 * start transaction of update of the inode map
2574 		 * addressing structure pointing to the new iag page;
2575 		 */
2576 		tid = txBegin(sb, COMMIT_FORCE);
2577 		down(&JFS_IP(ipimap)->commit_sem);
2578 
2579 		/* update the inode map addressing structure to point to it */
2580 		if ((rc =
2581 		     xtInsert(tid, ipimap, 0, blkno, xlen, &xaddr, 0))) {
2582 			txEnd(tid);
2583 			up(&JFS_IP(ipimap)->commit_sem);
2584 			/* Free the blocks allocated for the iag since it was
2585 			 * not successfully added to the inode map
2586 			 */
2587 			dbFree(ipimap, xaddr, (s64) xlen);
2588 
2589 			/* release the inode map lock */
2590 			IWRITE_UNLOCK(ipimap);
2591 
2592 			goto out;
2593 		}
2594 
2595 		/* update the inode map's inode to reflect the extension */
2596 		ipimap->i_size += PSIZE;
2597 		inode_add_bytes(ipimap, PSIZE);
2598 
2599 		/* assign a buffer for the page */
2600 		mp = get_metapage(ipimap, blkno, PSIZE, 0);
2601 		if (!mp) {
2602 			/*
2603 			 * This is very unlikely since we just created the
2604 			 * extent, but let's try to handle it correctly
2605 			 */
2606 			xtTruncate(tid, ipimap, ipimap->i_size - PSIZE,
2607 				   COMMIT_PWMAP);
2608 
2609 			txAbort(tid, 0);
2610 			txEnd(tid);
2611 
2612 			/* release the inode map lock */
2613 			IWRITE_UNLOCK(ipimap);
2614 
2615 			rc = -EIO;
2616 			goto out;
2617 		}
2618 		iagp = (struct iag *) mp->data;
2619 
2620 		/* init the iag */
2621 		memset(iagp, 0, sizeof(struct iag));
2622 		iagp->iagnum = cpu_to_le32(iagno);
2623 		iagp->inofreefwd = iagp->inofreeback = cpu_to_le32(-1);
2624 		iagp->extfreefwd = iagp->extfreeback = cpu_to_le32(-1);
2625 		iagp->iagfree = cpu_to_le32(-1);
2626 		iagp->nfreeinos = 0;
2627 		iagp->nfreeexts = cpu_to_le32(EXTSPERIAG);
2628 
2629 		/* initialize the free inode summary map (free extent
2630 		 * summary map initialization handled by bzero).
2631 		 */
2632 		for (i = 0; i < SMAPSZ; i++)
2633 			iagp->inosmap[i] = cpu_to_le32(ONES);
2634 
2635 		/*
2636 		 * Write and sync the metapage
2637 		 */
2638 		flush_metapage(mp);
2639 
2640 		/*
2641 		 * txCommit(COMMIT_FORCE) will synchronously write address
2642 		 * index pages and inode after commit in careful update order
2643 		 * of address index pages (right to left, bottom up);
2644 		 */
2645 		iplist[0] = ipimap;
2646 		rc = txCommit(tid, 1, &iplist[0], COMMIT_FORCE);
2647 
2648 		txEnd(tid);
2649 		up(&JFS_IP(ipimap)->commit_sem);
2650 
2651 		duplicateIXtree(sb, blkno, xlen, &xaddr);
2652 
2653 		/* update the next avaliable iag number */
2654 		imap->im_nextiag += 1;
2655 
2656 		/* Add the iag to the iag free list so we don't lose the iag
2657 		 * if a failure happens now.
2658 		 */
2659 		imap->im_freeiag = iagno;
2660 
2661 		/* Until we have logredo working, we want the imap inode &
2662 		 * control page to be up to date.
2663 		 */
2664 		diSync(ipimap);
2665 
2666 		/* release the inode map lock */
2667 		IWRITE_UNLOCK(ipimap);
2668 	}
2669 
2670 	/* obtain read lock on map */
2671 	IREAD_LOCK(ipimap);
2672 
2673 	/* read the iag */
2674 	if ((rc = diIAGRead(imap, iagno, &mp))) {
2675 		IREAD_UNLOCK(ipimap);
2676 		rc = -EIO;
2677 		goto out;
2678 	}
2679 	iagp = (struct iag *) mp->data;
2680 
2681 	/* remove the iag from the iag free list */
2682 	imap->im_freeiag = le32_to_cpu(iagp->iagfree);
2683 	iagp->iagfree = cpu_to_le32(-1);
2684 
2685 	/* set the return iag number and buffer pointer */
2686 	*iagnop = iagno;
2687 	*mpp = mp;
2688 
2689       out:
2690 	/* release the iag free lock */
2691 	IAGFREE_UNLOCK(imap);
2692 
2693 	return (rc);
2694 }
2695 
2696 /*
2697  * NAME:        diIAGRead()
2698  *
2699  * FUNCTION:    get the buffer for the specified iag within a fileset
2700  *		or aggregate inode map.
2701  *
2702  * PARAMETERS:
2703  *      imap  	- pointer to inode map control structure.
2704  *      iagno  	- iag number.
2705  *      bpp  	- point to buffer pointer to be filled in on successful
2706  *		  exit.
2707  *
2708  * SERIALIZATION:
2709  *	must have read lock on imap inode
2710  *	(When called by diExtendFS, the filesystem is quiesced, therefore
2711  *	 the read lock is unnecessary.)
2712  *
2713  * RETURN VALUES:
2714  *      0       - success.
2715  *      -EIO  	- i/o error.
2716  */
2717 static int diIAGRead(struct inomap * imap, int iagno, struct metapage ** mpp)
2718 {
2719 	struct inode *ipimap = imap->im_ipimap;
2720 	s64 blkno;
2721 
2722 	/* compute the logical block number of the iag. */
2723 	blkno = IAGTOLBLK(iagno, JFS_SBI(ipimap->i_sb)->l2nbperpage);
2724 
2725 	/* read the iag. */
2726 	*mpp = read_metapage(ipimap, blkno, PSIZE, 0);
2727 	if (*mpp == NULL) {
2728 		return -EIO;
2729 	}
2730 
2731 	return (0);
2732 }
2733 
2734 /*
2735  * NAME:        diFindFree()
2736  *
2737  * FUNCTION:    find the first free bit in a word starting at
2738  *		the specified bit position.
2739  *
2740  * PARAMETERS:
2741  *      word  	- word to be examined.
2742  *      start  	- starting bit position.
2743  *
2744  * RETURN VALUES:
2745  *      bit position of first free bit in the word or 32 if
2746  *	no free bits were found.
2747  */
2748 static int diFindFree(u32 word, int start)
2749 {
2750 	int bitno;
2751 	assert(start < 32);
2752 	/* scan the word for the first free bit. */
2753 	for (word <<= start, bitno = start; bitno < 32;
2754 	     bitno++, word <<= 1) {
2755 		if ((word & HIGHORDER) == 0)
2756 			break;
2757 	}
2758 	return (bitno);
2759 }
2760 
2761 /*
2762  * NAME:	diUpdatePMap()
2763  *
2764  * FUNCTION: Update the persistent map in an IAG for the allocation or
2765  *	freeing of the specified inode.
2766  *
2767  * PRE CONDITIONS: Working map has already been updated for allocate.
2768  *
2769  * PARAMETERS:
2770  *	ipimap	- Incore inode map inode
2771  *	inum	- Number of inode to mark in permanent map
2772  *	is_free	- If TRUE indicates inode should be marked freed, otherwise
2773  *		  indicates inode should be marked allocated.
2774  *
2775  * RETURN VALUES:
2776  *		0 for success
2777  */
2778 int
2779 diUpdatePMap(struct inode *ipimap,
2780 	     unsigned long inum, boolean_t is_free, struct tblock * tblk)
2781 {
2782 	int rc;
2783 	struct iag *iagp;
2784 	struct metapage *mp;
2785 	int iagno, ino, extno, bitno;
2786 	struct inomap *imap;
2787 	u32 mask;
2788 	struct jfs_log *log;
2789 	int lsn, difft, diffp;
2790 	unsigned long flags;
2791 
2792 	imap = JFS_IP(ipimap)->i_imap;
2793 	/* get the iag number containing the inode */
2794 	iagno = INOTOIAG(inum);
2795 	/* make sure that the iag is contained within the map */
2796 	if (iagno >= imap->im_nextiag) {
2797 		jfs_error(ipimap->i_sb,
2798 			  "diUpdatePMap: the iag is outside the map");
2799 		return -EIO;
2800 	}
2801 	/* read the iag */
2802 	IREAD_LOCK(ipimap);
2803 	rc = diIAGRead(imap, iagno, &mp);
2804 	IREAD_UNLOCK(ipimap);
2805 	if (rc)
2806 		return (rc);
2807 	metapage_wait_for_io(mp);
2808 	iagp = (struct iag *) mp->data;
2809 	/* get the inode number and extent number of the inode within
2810 	 * the iag and the inode number within the extent.
2811 	 */
2812 	ino = inum & (INOSPERIAG - 1);
2813 	extno = ino >> L2INOSPEREXT;
2814 	bitno = ino & (INOSPEREXT - 1);
2815 	mask = HIGHORDER >> bitno;
2816 	/*
2817 	 * mark the inode free in persistent map:
2818 	 */
2819 	if (is_free == TRUE) {
2820 		/* The inode should have been allocated both in working
2821 		 * map and in persistent map;
2822 		 * the inode will be freed from working map at the release
2823 		 * of last reference release;
2824 		 */
2825 		if (!(le32_to_cpu(iagp->wmap[extno]) & mask)) {
2826 			jfs_error(ipimap->i_sb,
2827 				  "diUpdatePMap: inode %ld not marked as "
2828 				  "allocated in wmap!", inum);
2829 		}
2830 		if (!(le32_to_cpu(iagp->pmap[extno]) & mask)) {
2831 			jfs_error(ipimap->i_sb,
2832 				  "diUpdatePMap: inode %ld not marked as "
2833 				  "allocated in pmap!", inum);
2834 		}
2835 		/* update the bitmap for the extent of the freed inode */
2836 		iagp->pmap[extno] &= cpu_to_le32(~mask);
2837 	}
2838 	/*
2839 	 * mark the inode allocated in persistent map:
2840 	 */
2841 	else {
2842 		/* The inode should be already allocated in the working map
2843 		 * and should be free in persistent map;
2844 		 */
2845 		if (!(le32_to_cpu(iagp->wmap[extno]) & mask)) {
2846 			release_metapage(mp);
2847 			jfs_error(ipimap->i_sb,
2848 				  "diUpdatePMap: the inode is not allocated in "
2849 				  "the working map");
2850 			return -EIO;
2851 		}
2852 		if ((le32_to_cpu(iagp->pmap[extno]) & mask) != 0) {
2853 			release_metapage(mp);
2854 			jfs_error(ipimap->i_sb,
2855 				  "diUpdatePMap: the inode is not free in the "
2856 				  "persistent map");
2857 			return -EIO;
2858 		}
2859 		/* update the bitmap for the extent of the allocated inode */
2860 		iagp->pmap[extno] |= cpu_to_le32(mask);
2861 	}
2862 	/*
2863 	 * update iag lsn
2864 	 */
2865 	lsn = tblk->lsn;
2866 	log = JFS_SBI(tblk->sb)->log;
2867 	if (mp->lsn != 0) {
2868 		/* inherit older/smaller lsn */
2869 		logdiff(difft, lsn, log);
2870 		logdiff(diffp, mp->lsn, log);
2871 		LOGSYNC_LOCK(log, flags);
2872 		if (difft < diffp) {
2873 			mp->lsn = lsn;
2874 			/* move mp after tblock in logsync list */
2875 			list_move(&mp->synclist, &tblk->synclist);
2876 		}
2877 		/* inherit younger/larger clsn */
2878 		assert(mp->clsn);
2879 		logdiff(difft, tblk->clsn, log);
2880 		logdiff(diffp, mp->clsn, log);
2881 		if (difft > diffp)
2882 			mp->clsn = tblk->clsn;
2883 		LOGSYNC_UNLOCK(log, flags);
2884 	} else {
2885 		mp->log = log;
2886 		mp->lsn = lsn;
2887 		/* insert mp after tblock in logsync list */
2888 		LOGSYNC_LOCK(log, flags);
2889 		log->count++;
2890 		list_add(&mp->synclist, &tblk->synclist);
2891 		mp->clsn = tblk->clsn;
2892 		LOGSYNC_UNLOCK(log, flags);
2893 	}
2894 	write_metapage(mp);
2895 	return (0);
2896 }
2897 
2898 /*
2899  *	diExtendFS()
2900  *
2901  * function: update imap for extendfs();
2902  *
2903  * note: AG size has been increased s.t. each k old contiguous AGs are
2904  * coalesced into a new AG;
2905  */
2906 int diExtendFS(struct inode *ipimap, struct inode *ipbmap)
2907 {
2908 	int rc, rcx = 0;
2909 	struct inomap *imap = JFS_IP(ipimap)->i_imap;
2910 	struct iag *iagp = NULL, *hiagp = NULL;
2911 	struct bmap *mp = JFS_SBI(ipbmap->i_sb)->bmap;
2912 	struct metapage *bp, *hbp;
2913 	int i, n, head;
2914 	int numinos, xnuminos = 0, xnumfree = 0;
2915 	s64 agstart;
2916 
2917 	jfs_info("diExtendFS: nextiag:%d numinos:%d numfree:%d",
2918 		   imap->im_nextiag, atomic_read(&imap->im_numinos),
2919 		   atomic_read(&imap->im_numfree));
2920 
2921 	/*
2922 	 *      reconstruct imap
2923 	 *
2924 	 * coalesce contiguous k (newAGSize/oldAGSize) AGs;
2925 	 * i.e., (AGi, ..., AGj) where i = k*n and j = k*(n+1) - 1 to AGn;
2926 	 * note: new AG size = old AG size * (2**x).
2927 	 */
2928 
2929 	/* init per AG control information im_agctl[] */
2930 	for (i = 0; i < MAXAG; i++) {
2931 		imap->im_agctl[i].inofree = -1;
2932 		imap->im_agctl[i].extfree = -1;
2933 		imap->im_agctl[i].numinos = 0;	/* number of backed inodes */
2934 		imap->im_agctl[i].numfree = 0;	/* number of free backed inodes */
2935 	}
2936 
2937 	/*
2938 	 *      process each iag page of the map.
2939 	 *
2940 	 * rebuild AG Free Inode List, AG Free Inode Extent List;
2941 	 */
2942 	for (i = 0; i < imap->im_nextiag; i++) {
2943 		if ((rc = diIAGRead(imap, i, &bp))) {
2944 			rcx = rc;
2945 			continue;
2946 		}
2947 		iagp = (struct iag *) bp->data;
2948 		if (le32_to_cpu(iagp->iagnum) != i) {
2949 			release_metapage(bp);
2950 			jfs_error(ipimap->i_sb,
2951 				  "diExtendFs: unexpected value of iagnum");
2952 			return -EIO;
2953 		}
2954 
2955 		/* leave free iag in the free iag list */
2956 		if (iagp->nfreeexts == cpu_to_le32(EXTSPERIAG)) {
2957 		        release_metapage(bp);
2958 			continue;
2959 		}
2960 
2961 		/* agstart that computes to the same ag is treated as same; */
2962 		agstart = le64_to_cpu(iagp->agstart);
2963 		/* iagp->agstart = agstart & ~(mp->db_agsize - 1); */
2964 		n = agstart >> mp->db_agl2size;
2965 
2966 		/* compute backed inodes */
2967 		numinos = (EXTSPERIAG - le32_to_cpu(iagp->nfreeexts))
2968 		    << L2INOSPEREXT;
2969 		if (numinos > 0) {
2970 			/* merge AG backed inodes */
2971 			imap->im_agctl[n].numinos += numinos;
2972 			xnuminos += numinos;
2973 		}
2974 
2975 		/* if any backed free inodes, insert at AG free inode list */
2976 		if ((int) le32_to_cpu(iagp->nfreeinos) > 0) {
2977 			if ((head = imap->im_agctl[n].inofree) == -1) {
2978 				iagp->inofreefwd = cpu_to_le32(-1);
2979 				iagp->inofreeback = cpu_to_le32(-1);
2980 			} else {
2981 				if ((rc = diIAGRead(imap, head, &hbp))) {
2982 					rcx = rc;
2983 					goto nextiag;
2984 				}
2985 				hiagp = (struct iag *) hbp->data;
2986 				hiagp->inofreeback = iagp->iagnum;
2987 				iagp->inofreefwd = cpu_to_le32(head);
2988 				iagp->inofreeback = cpu_to_le32(-1);
2989 				write_metapage(hbp);
2990 			}
2991 
2992 			imap->im_agctl[n].inofree =
2993 			    le32_to_cpu(iagp->iagnum);
2994 
2995 			/* merge AG backed free inodes */
2996 			imap->im_agctl[n].numfree +=
2997 			    le32_to_cpu(iagp->nfreeinos);
2998 			xnumfree += le32_to_cpu(iagp->nfreeinos);
2999 		}
3000 
3001 		/* if any free extents, insert at AG free extent list */
3002 		if (le32_to_cpu(iagp->nfreeexts) > 0) {
3003 			if ((head = imap->im_agctl[n].extfree) == -1) {
3004 				iagp->extfreefwd = cpu_to_le32(-1);
3005 				iagp->extfreeback = cpu_to_le32(-1);
3006 			} else {
3007 				if ((rc = diIAGRead(imap, head, &hbp))) {
3008 					rcx = rc;
3009 					goto nextiag;
3010 				}
3011 				hiagp = (struct iag *) hbp->data;
3012 				hiagp->extfreeback = iagp->iagnum;
3013 				iagp->extfreefwd = cpu_to_le32(head);
3014 				iagp->extfreeback = cpu_to_le32(-1);
3015 				write_metapage(hbp);
3016 			}
3017 
3018 			imap->im_agctl[n].extfree =
3019 			    le32_to_cpu(iagp->iagnum);
3020 		}
3021 
3022 	      nextiag:
3023 		write_metapage(bp);
3024 	}
3025 
3026 	if (xnuminos != atomic_read(&imap->im_numinos) ||
3027 	    xnumfree != atomic_read(&imap->im_numfree)) {
3028 		jfs_error(ipimap->i_sb,
3029 			  "diExtendFs: numinos or numfree incorrect");
3030 		return -EIO;
3031 	}
3032 
3033 	return rcx;
3034 }
3035 
3036 
3037 /*
3038  *	duplicateIXtree()
3039  *
3040  * serialization: IWRITE_LOCK held on entry/exit
3041  *
3042  * note: shadow page with regular inode (rel.2);
3043  */
3044 static void duplicateIXtree(struct super_block *sb, s64 blkno,
3045 			    int xlen, s64 *xaddr)
3046 {
3047 	struct jfs_superblock *j_sb;
3048 	struct buffer_head *bh;
3049 	struct inode *ip;
3050 	tid_t tid;
3051 
3052 	/* if AIT2 ipmap2 is bad, do not try to update it */
3053 	if (JFS_SBI(sb)->mntflag & JFS_BAD_SAIT)	/* s_flag */
3054 		return;
3055 	ip = diReadSpecial(sb, FILESYSTEM_I, 1);
3056 	if (ip == NULL) {
3057 		JFS_SBI(sb)->mntflag |= JFS_BAD_SAIT;
3058 		if (readSuper(sb, &bh))
3059 			return;
3060 		j_sb = (struct jfs_superblock *)bh->b_data;
3061 		j_sb->s_flag |= cpu_to_le32(JFS_BAD_SAIT);
3062 
3063 		mark_buffer_dirty(bh);
3064 		sync_dirty_buffer(bh);
3065 		brelse(bh);
3066 		return;
3067 	}
3068 
3069 	/* start transaction */
3070 	tid = txBegin(sb, COMMIT_FORCE);
3071 	/* update the inode map addressing structure to point to it */
3072 	if (xtInsert(tid, ip, 0, blkno, xlen, xaddr, 0)) {
3073 		JFS_SBI(sb)->mntflag |= JFS_BAD_SAIT;
3074 		txAbort(tid, 1);
3075 		goto cleanup;
3076 
3077 	}
3078 	/* update the inode map's inode to reflect the extension */
3079 	ip->i_size += PSIZE;
3080 	inode_add_bytes(ip, PSIZE);
3081 	txCommit(tid, 1, &ip, COMMIT_FORCE);
3082       cleanup:
3083 	txEnd(tid);
3084 	diFreeSpecial(ip);
3085 }
3086 
3087 /*
3088  * NAME:        copy_from_dinode()
3089  *
3090  * FUNCTION:    Copies inode info from disk inode to in-memory inode
3091  *
3092  * RETURN VALUES:
3093  *      0       - success
3094  *      -ENOMEM	- insufficient memory
3095  */
3096 static int copy_from_dinode(struct dinode * dip, struct inode *ip)
3097 {
3098 	struct jfs_inode_info *jfs_ip = JFS_IP(ip);
3099 
3100 	jfs_ip->fileset = le32_to_cpu(dip->di_fileset);
3101 	jfs_ip->mode2 = le32_to_cpu(dip->di_mode);
3102 
3103 	ip->i_mode = le32_to_cpu(dip->di_mode) & 0xffff;
3104 	ip->i_nlink = le32_to_cpu(dip->di_nlink);
3105 	ip->i_uid = le32_to_cpu(dip->di_uid);
3106 	ip->i_gid = le32_to_cpu(dip->di_gid);
3107 	ip->i_size = le64_to_cpu(dip->di_size);
3108 	ip->i_atime.tv_sec = le32_to_cpu(dip->di_atime.tv_sec);
3109 	ip->i_atime.tv_nsec = le32_to_cpu(dip->di_atime.tv_nsec);
3110 	ip->i_mtime.tv_sec = le32_to_cpu(dip->di_mtime.tv_sec);
3111 	ip->i_mtime.tv_nsec = le32_to_cpu(dip->di_mtime.tv_nsec);
3112 	ip->i_ctime.tv_sec = le32_to_cpu(dip->di_ctime.tv_sec);
3113 	ip->i_ctime.tv_nsec = le32_to_cpu(dip->di_ctime.tv_nsec);
3114 	ip->i_blksize = ip->i_sb->s_blocksize;
3115 	ip->i_blocks = LBLK2PBLK(ip->i_sb, le64_to_cpu(dip->di_nblocks));
3116 	ip->i_generation = le32_to_cpu(dip->di_gen);
3117 
3118 	jfs_ip->ixpxd = dip->di_ixpxd;	/* in-memory pxd's are little-endian */
3119 	jfs_ip->acl = dip->di_acl;	/* as are dxd's */
3120 	jfs_ip->ea = dip->di_ea;
3121 	jfs_ip->next_index = le32_to_cpu(dip->di_next_index);
3122 	jfs_ip->otime = le32_to_cpu(dip->di_otime.tv_sec);
3123 	jfs_ip->acltype = le32_to_cpu(dip->di_acltype);
3124 
3125 	if (S_ISCHR(ip->i_mode) || S_ISBLK(ip->i_mode)) {
3126 		jfs_ip->dev = le32_to_cpu(dip->di_rdev);
3127 		ip->i_rdev = new_decode_dev(jfs_ip->dev);
3128 	}
3129 
3130 	if (S_ISDIR(ip->i_mode)) {
3131 		memcpy(&jfs_ip->i_dirtable, &dip->di_dirtable, 384);
3132 	} else if (S_ISREG(ip->i_mode) || S_ISLNK(ip->i_mode)) {
3133 		memcpy(&jfs_ip->i_xtroot, &dip->di_xtroot, 288);
3134 	} else
3135 		memcpy(&jfs_ip->i_inline_ea, &dip->di_inlineea, 128);
3136 
3137 	/* Zero the in-memory-only stuff */
3138 	jfs_ip->cflag = 0;
3139 	jfs_ip->btindex = 0;
3140 	jfs_ip->btorder = 0;
3141 	jfs_ip->bxflag = 0;
3142 	jfs_ip->blid = 0;
3143 	jfs_ip->atlhead = 0;
3144 	jfs_ip->atltail = 0;
3145 	jfs_ip->xtlid = 0;
3146 	return (0);
3147 }
3148 
3149 /*
3150  * NAME:        copy_to_dinode()
3151  *
3152  * FUNCTION:    Copies inode info from in-memory inode to disk inode
3153  */
3154 static void copy_to_dinode(struct dinode * dip, struct inode *ip)
3155 {
3156 	struct jfs_inode_info *jfs_ip = JFS_IP(ip);
3157 
3158 	dip->di_fileset = cpu_to_le32(jfs_ip->fileset);
3159 	dip->di_inostamp = cpu_to_le32(JFS_SBI(ip->i_sb)->inostamp);
3160 	dip->di_number = cpu_to_le32(ip->i_ino);
3161 	dip->di_gen = cpu_to_le32(ip->i_generation);
3162 	dip->di_size = cpu_to_le64(ip->i_size);
3163 	dip->di_nblocks = cpu_to_le64(PBLK2LBLK(ip->i_sb, ip->i_blocks));
3164 	dip->di_nlink = cpu_to_le32(ip->i_nlink);
3165 	dip->di_uid = cpu_to_le32(ip->i_uid);
3166 	dip->di_gid = cpu_to_le32(ip->i_gid);
3167 	/*
3168 	 * mode2 is only needed for storing the higher order bits.
3169 	 * Trust i_mode for the lower order ones
3170 	 */
3171 	dip->di_mode = cpu_to_le32((jfs_ip->mode2 & 0xffff0000) | ip->i_mode);
3172 	dip->di_atime.tv_sec = cpu_to_le32(ip->i_atime.tv_sec);
3173 	dip->di_atime.tv_nsec = cpu_to_le32(ip->i_atime.tv_nsec);
3174 	dip->di_ctime.tv_sec = cpu_to_le32(ip->i_ctime.tv_sec);
3175 	dip->di_ctime.tv_nsec = cpu_to_le32(ip->i_ctime.tv_nsec);
3176 	dip->di_mtime.tv_sec = cpu_to_le32(ip->i_mtime.tv_sec);
3177 	dip->di_mtime.tv_nsec = cpu_to_le32(ip->i_mtime.tv_nsec);
3178 	dip->di_ixpxd = jfs_ip->ixpxd;	/* in-memory pxd's are little-endian */
3179 	dip->di_acl = jfs_ip->acl;	/* as are dxd's */
3180 	dip->di_ea = jfs_ip->ea;
3181 	dip->di_next_index = cpu_to_le32(jfs_ip->next_index);
3182 	dip->di_otime.tv_sec = cpu_to_le32(jfs_ip->otime);
3183 	dip->di_otime.tv_nsec = 0;
3184 	dip->di_acltype = cpu_to_le32(jfs_ip->acltype);
3185 	if (S_ISCHR(ip->i_mode) || S_ISBLK(ip->i_mode))
3186 		dip->di_rdev = cpu_to_le32(jfs_ip->dev);
3187 }
3188 
3189 #ifdef	_JFS_DEBUG_IMAP
3190 /*
3191  *	DBGdiInit()
3192  */
3193 static void *DBGdiInit(struct inomap * imap)
3194 {
3195 	u32 *dimap;
3196 	int size;
3197 	size = 64 * 1024;
3198 	if ((dimap = (u32 *) xmalloc(size, L2PSIZE, kernel_heap)) == NULL)
3199 		assert(0);
3200 	bzero((void *) dimap, size);
3201 	imap->im_DBGdimap = dimap;
3202 }
3203 
3204 /*
3205  *	DBGdiAlloc()
3206  */
3207 static void DBGdiAlloc(struct inomap * imap, ino_t ino)
3208 {
3209 	u32 *dimap = imap->im_DBGdimap;
3210 	int w, b;
3211 	u32 m;
3212 	w = ino >> 5;
3213 	b = ino & 31;
3214 	m = 0x80000000 >> b;
3215 	assert(w < 64 * 256);
3216 	if (dimap[w] & m) {
3217 		printk("DEBUG diAlloc: duplicate alloc ino:0x%x\n", ino);
3218 	}
3219 	dimap[w] |= m;
3220 }
3221 
3222 /*
3223  *	DBGdiFree()
3224  */
3225 static void DBGdiFree(struct inomap * imap, ino_t ino)
3226 {
3227 	u32 *dimap = imap->im_DBGdimap;
3228 	int w, b;
3229 	u32 m;
3230 	w = ino >> 5;
3231 	b = ino & 31;
3232 	m = 0x80000000 >> b;
3233 	assert(w < 64 * 256);
3234 	if ((dimap[w] & m) == 0) {
3235 		printk("DEBUG diFree: duplicate free ino:0x%x\n", ino);
3236 	}
3237 	dimap[w] &= ~m;
3238 }
3239 
3240 static void dump_cp(struct inomap * ipimap, char *function, int line)
3241 {
3242 	printk("\n* ********* *\nControl Page %s %d\n", function, line);
3243 	printk("FreeIAG %d\tNextIAG %d\n", ipimap->im_freeiag,
3244 	       ipimap->im_nextiag);
3245 	printk("NumInos %d\tNumFree %d\n",
3246 	       atomic_read(&ipimap->im_numinos),
3247 	       atomic_read(&ipimap->im_numfree));
3248 	printk("AG InoFree %d\tAG ExtFree %d\n",
3249 	       ipimap->im_agctl[0].inofree, ipimap->im_agctl[0].extfree);
3250 	printk("AG NumInos %d\tAG NumFree %d\n",
3251 	       ipimap->im_agctl[0].numinos, ipimap->im_agctl[0].numfree);
3252 }
3253 
3254 static void dump_iag(struct iag * iag, char *function, int line)
3255 {
3256 	printk("\n* ********* *\nIAG %s %d\n", function, line);
3257 	printk("IagNum %d\tIAG Free %d\n", le32_to_cpu(iag->iagnum),
3258 	       le32_to_cpu(iag->iagfree));
3259 	printk("InoFreeFwd %d\tInoFreeBack %d\n",
3260 	       le32_to_cpu(iag->inofreefwd),
3261 	       le32_to_cpu(iag->inofreeback));
3262 	printk("ExtFreeFwd %d\tExtFreeBack %d\n",
3263 	       le32_to_cpu(iag->extfreefwd),
3264 	       le32_to_cpu(iag->extfreeback));
3265 	printk("NFreeInos %d\tNFreeExts %d\n", le32_to_cpu(iag->nfreeinos),
3266 	       le32_to_cpu(iag->nfreeexts));
3267 }
3268 #endif				/* _JFS_DEBUG_IMAP */
3269