xref: /openbmc/linux/fs/jfs/jfs_imap.c (revision 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2)
1 /*
2  *   Copyright (C) International Business Machines Corp., 2000-2004
3  *
4  *   This program is free software;  you can redistribute it and/or modify
5  *   it under the terms of the GNU General Public License as published by
6  *   the Free Software Foundation; either version 2 of the License, or
7  *   (at your option) any later version.
8  *
9  *   This program is distributed in the hope that it will be useful,
10  *   but WITHOUT ANY WARRANTY;  without even the implied warranty of
11  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See
12  *   the GNU General Public License for more details.
13  *
14  *   You should have received a copy of the GNU General Public License
15  *   along with this program;  if not, write to the Free Software
16  *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
17  */
18 
19 /*
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_filsys.h"
51 #include "jfs_dinode.h"
52 #include "jfs_dmap.h"
53 #include "jfs_imap.h"
54 #include "jfs_metapage.h"
55 #include "jfs_superblock.h"
56 #include "jfs_debug.h"
57 
58 /*
59  * imap locks
60  */
61 /* iag free list lock */
62 #define IAGFREE_LOCK_INIT(imap)		init_MUTEX(&imap->im_freelock)
63 #define IAGFREE_LOCK(imap)		down(&imap->im_freelock)
64 #define IAGFREE_UNLOCK(imap)		up(&imap->im_freelock)
65 
66 /* per ag iag list locks */
67 #define AG_LOCK_INIT(imap,index)	init_MUTEX(&(imap->im_aglock[index]))
68 #define AG_LOCK(imap,agno)		down(&imap->im_aglock[agno])
69 #define AG_UNLOCK(imap,agno)		up(&imap->im_aglock[agno])
70 
71 /*
72  * external references
73  */
74 extern struct address_space_operations jfs_aops;
75 
76 /*
77  * forward references
78  */
79 static int diAllocAG(struct inomap *, int, boolean_t, struct inode *);
80 static int diAllocAny(struct inomap *, int, boolean_t, struct inode *);
81 static int diAllocBit(struct inomap *, struct iag *, int);
82 static int diAllocExt(struct inomap *, int, struct inode *);
83 static int diAllocIno(struct inomap *, int, struct inode *);
84 static int diFindFree(u32, int);
85 static int diNewExt(struct inomap *, struct iag *, int);
86 static int diNewIAG(struct inomap *, int *, int, struct metapage **);
87 static void duplicateIXtree(struct super_block *, s64, int, s64 *);
88 
89 static int diIAGRead(struct inomap * imap, int, struct metapage **);
90 static int copy_from_dinode(struct dinode *, struct inode *);
91 static void copy_to_dinode(struct dinode *, struct inode *);
92 
93 /*
94  *	debug code for double-checking inode map
95  */
96 /* #define	_JFS_DEBUG_IMAP	1 */
97 
98 #ifdef	_JFS_DEBUG_IMAP
99 #define DBG_DIINIT(imap)	DBGdiInit(imap)
100 #define DBG_DIALLOC(imap, ino)	DBGdiAlloc(imap, ino)
101 #define DBG_DIFREE(imap, ino)	DBGdiFree(imap, ino)
102 
103 static void *DBGdiInit(struct inomap * imap);
104 static void DBGdiAlloc(struct inomap * imap, ino_t ino);
105 static void DBGdiFree(struct inomap * imap, ino_t ino);
106 #else
107 #define DBG_DIINIT(imap)
108 #define DBG_DIALLOC(imap, ino)
109 #define DBG_DIFREE(imap, ino)
110 #endif				/* _JFS_DEBUG_IMAP */
111 
112 /*
113  * NAME:        diMount()
114  *
115  * FUNCTION:    initialize the incore inode map control structures for
116  *		a fileset or aggregate init time.
117  *
118  *              the inode map's control structure (dinomap) is
119  *              brought in from disk and placed in virtual memory.
120  *
121  * PARAMETERS:
122  *      ipimap  - pointer to inode map inode for the aggregate or fileset.
123  *
124  * RETURN VALUES:
125  *      0       - success
126  *      -ENOMEM  - insufficient free virtual memory.
127  *      -EIO  	- i/o error.
128  */
129 int diMount(struct inode *ipimap)
130 {
131 	struct inomap *imap;
132 	struct metapage *mp;
133 	int index;
134 	struct dinomap_disk *dinom_le;
135 
136 	/*
137 	 * allocate/initialize the in-memory inode map control structure
138 	 */
139 	/* allocate the in-memory inode map control structure. */
140 	imap = (struct inomap *) kmalloc(sizeof(struct inomap), GFP_KERNEL);
141 	if (imap == NULL) {
142 		jfs_err("diMount: kmalloc returned NULL!");
143 		return -ENOMEM;
144 	}
145 
146 	/* read the on-disk inode map control structure. */
147 
148 	mp = read_metapage(ipimap,
149 			   IMAPBLKNO << JFS_SBI(ipimap->i_sb)->l2nbperpage,
150 			   PSIZE, 0);
151 	if (mp == NULL) {
152 		kfree(imap);
153 		return -EIO;
154 	}
155 
156 	/* copy the on-disk version to the in-memory version. */
157 	dinom_le = (struct dinomap_disk *) mp->data;
158 	imap->im_freeiag = le32_to_cpu(dinom_le->in_freeiag);
159 	imap->im_nextiag = le32_to_cpu(dinom_le->in_nextiag);
160 	atomic_set(&imap->im_numinos, le32_to_cpu(dinom_le->in_numinos));
161 	atomic_set(&imap->im_numfree, le32_to_cpu(dinom_le->in_numfree));
162 	imap->im_nbperiext = le32_to_cpu(dinom_le->in_nbperiext);
163 	imap->im_l2nbperiext = le32_to_cpu(dinom_le->in_l2nbperiext);
164 	for (index = 0; index < MAXAG; index++) {
165 		imap->im_agctl[index].inofree =
166 		    le32_to_cpu(dinom_le->in_agctl[index].inofree);
167 		imap->im_agctl[index].extfree =
168 		    le32_to_cpu(dinom_le->in_agctl[index].extfree);
169 		imap->im_agctl[index].numinos =
170 		    le32_to_cpu(dinom_le->in_agctl[index].numinos);
171 		imap->im_agctl[index].numfree =
172 		    le32_to_cpu(dinom_le->in_agctl[index].numfree);
173 	}
174 
175 	/* release the buffer. */
176 	release_metapage(mp);
177 
178 	/*
179 	 * allocate/initialize inode allocation map locks
180 	 */
181 	/* allocate and init iag free list lock */
182 	IAGFREE_LOCK_INIT(imap);
183 
184 	/* allocate and init ag list locks */
185 	for (index = 0; index < MAXAG; index++) {
186 		AG_LOCK_INIT(imap, index);
187 	}
188 
189 	/* bind the inode map inode and inode map control structure
190 	 * to each other.
191 	 */
192 	imap->im_ipimap = ipimap;
193 	JFS_IP(ipimap)->i_imap = imap;
194 
195 //      DBG_DIINIT(imap);
196 
197 	return (0);
198 }
199 
200 
201 /*
202  * NAME:        diUnmount()
203  *
204  * FUNCTION:    write to disk the incore inode map control structures for
205  *		a fileset or aggregate at unmount time.
206  *
207  * PARAMETERS:
208  *      ipimap  - pointer to inode map inode for the aggregate or fileset.
209  *
210  * RETURN VALUES:
211  *      0       - success
212  *      -ENOMEM  - insufficient free virtual memory.
213  *      -EIO  	- i/o error.
214  */
215 int diUnmount(struct inode *ipimap, int mounterror)
216 {
217 	struct inomap *imap = JFS_IP(ipimap)->i_imap;
218 
219 	/*
220 	 * update the on-disk inode map control structure
221 	 */
222 
223 	if (!(mounterror || isReadOnly(ipimap)))
224 		diSync(ipimap);
225 
226 	/*
227 	 * Invalidate the page cache buffers
228 	 */
229 	truncate_inode_pages(ipimap->i_mapping, 0);
230 
231 	/*
232 	 * free in-memory control structure
233 	 */
234 	kfree(imap);
235 
236 	return (0);
237 }
238 
239 
240 /*
241  *	diSync()
242  */
243 int diSync(struct inode *ipimap)
244 {
245 	struct dinomap_disk *dinom_le;
246 	struct inomap *imp = JFS_IP(ipimap)->i_imap;
247 	struct metapage *mp;
248 	int index;
249 
250 	/*
251 	 * write imap global conrol page
252 	 */
253 	/* read the on-disk inode map control structure */
254 	mp = get_metapage(ipimap,
255 			  IMAPBLKNO << JFS_SBI(ipimap->i_sb)->l2nbperpage,
256 			  PSIZE, 0);
257 	if (mp == NULL) {
258 		jfs_err("diSync: get_metapage failed!");
259 		return -EIO;
260 	}
261 
262 	/* copy the in-memory version to the on-disk version */
263 	dinom_le = (struct dinomap_disk *) mp->data;
264 	dinom_le->in_freeiag = cpu_to_le32(imp->im_freeiag);
265 	dinom_le->in_nextiag = cpu_to_le32(imp->im_nextiag);
266 	dinom_le->in_numinos = cpu_to_le32(atomic_read(&imp->im_numinos));
267 	dinom_le->in_numfree = cpu_to_le32(atomic_read(&imp->im_numfree));
268 	dinom_le->in_nbperiext = cpu_to_le32(imp->im_nbperiext);
269 	dinom_le->in_l2nbperiext = cpu_to_le32(imp->im_l2nbperiext);
270 	for (index = 0; index < MAXAG; index++) {
271 		dinom_le->in_agctl[index].inofree =
272 		    cpu_to_le32(imp->im_agctl[index].inofree);
273 		dinom_le->in_agctl[index].extfree =
274 		    cpu_to_le32(imp->im_agctl[index].extfree);
275 		dinom_le->in_agctl[index].numinos =
276 		    cpu_to_le32(imp->im_agctl[index].numinos);
277 		dinom_le->in_agctl[index].numfree =
278 		    cpu_to_le32(imp->im_agctl[index].numfree);
279 	}
280 
281 	/* write out the control structure */
282 	write_metapage(mp);
283 
284 	/*
285 	 * write out dirty pages of imap
286 	 */
287 	filemap_fdatawrite(ipimap->i_mapping);
288 	filemap_fdatawait(ipimap->i_mapping);
289 
290 	diWriteSpecial(ipimap, 0);
291 
292 	return (0);
293 }
294 
295 
296 /*
297  * NAME:        diRead()
298  *
299  * FUNCTION:    initialize an incore inode from disk.
300  *
301  *		on entry, the specifed incore inode should itself
302  *		specify the disk inode number corresponding to the
303  *		incore inode (i.e. i_number should be initialized).
304  *
305  *		this routine handles incore inode initialization for
306  *		both "special" and "regular" inodes.  special inodes
307  *		are those required early in the mount process and
308  *	        require special handling since much of the file system
309  *		is not yet initialized.  these "special" inodes are
310  *		identified by a NULL inode map inode pointer and are
311  *		actually initialized by a call to diReadSpecial().
312  *
313  *		for regular inodes, the iag describing the disk inode
314  *		is read from disk to determine the inode extent address
315  *		for the disk inode.  with the inode extent address in
316  *		hand, the page of the extent that contains the disk
317  *		inode is read and the disk inode is copied to the
318  *		incore inode.
319  *
320  * PARAMETERS:
321  *      ip  -  pointer to incore inode to be initialized from disk.
322  *
323  * RETURN VALUES:
324  *      0       - success
325  *      -EIO  	- i/o error.
326  *      -ENOMEM	- insufficient memory
327  *
328  */
329 int diRead(struct inode *ip)
330 {
331 	struct jfs_sb_info *sbi = JFS_SBI(ip->i_sb);
332 	int iagno, ino, extno, rc;
333 	struct inode *ipimap;
334 	struct dinode *dp;
335 	struct iag *iagp;
336 	struct metapage *mp;
337 	s64 blkno, agstart;
338 	struct inomap *imap;
339 	int block_offset;
340 	int inodes_left;
341 	uint pageno;
342 	int rel_inode;
343 
344 	jfs_info("diRead: ino = %ld", ip->i_ino);
345 
346 	ipimap = sbi->ipimap;
347 	JFS_IP(ip)->ipimap = ipimap;
348 
349 	/* determine the iag number for this inode (number) */
350 	iagno = INOTOIAG(ip->i_ino);
351 
352 	/* read the iag */
353 	imap = JFS_IP(ipimap)->i_imap;
354 	IREAD_LOCK(ipimap);
355 	rc = diIAGRead(imap, iagno, &mp);
356 	IREAD_UNLOCK(ipimap);
357 	if (rc) {
358 		jfs_err("diRead: diIAGRead returned %d", rc);
359 		return (rc);
360 	}
361 
362 	iagp = (struct iag *) mp->data;
363 
364 	/* determine inode extent that holds the disk inode */
365 	ino = ip->i_ino & (INOSPERIAG - 1);
366 	extno = ino >> L2INOSPEREXT;
367 
368 	if ((lengthPXD(&iagp->inoext[extno]) != imap->im_nbperiext) ||
369 	    (addressPXD(&iagp->inoext[extno]) == 0)) {
370 		release_metapage(mp);
371 		return -ESTALE;
372 	}
373 
374 	/* get disk block number of the page within the inode extent
375 	 * that holds the disk inode.
376 	 */
377 	blkno = INOPBLK(&iagp->inoext[extno], ino, sbi->l2nbperpage);
378 
379 	/* get the ag for the iag */
380 	agstart = le64_to_cpu(iagp->agstart);
381 
382 	release_metapage(mp);
383 
384 	rel_inode = (ino & (INOSPERPAGE - 1));
385 	pageno = blkno >> sbi->l2nbperpage;
386 
387 	if ((block_offset = ((u32) blkno & (sbi->nbperpage - 1)))) {
388 		/*
389 		 * OS/2 didn't always align inode extents on page boundaries
390 		 */
391 		inodes_left =
392 		     (sbi->nbperpage - block_offset) << sbi->l2niperblk;
393 
394 		if (rel_inode < inodes_left)
395 			rel_inode += block_offset << sbi->l2niperblk;
396 		else {
397 			pageno += 1;
398 			rel_inode -= inodes_left;
399 		}
400 	}
401 
402 	/* read the page of disk inode */
403 	mp = read_metapage(ipimap, pageno << sbi->l2nbperpage, PSIZE, 1);
404 	if (mp == 0) {
405 		jfs_err("diRead: read_metapage failed");
406 		return -EIO;
407 	}
408 
409 	/* locate the the disk inode requested */
410 	dp = (struct dinode *) mp->data;
411 	dp += rel_inode;
412 
413 	if (ip->i_ino != le32_to_cpu(dp->di_number)) {
414 		jfs_error(ip->i_sb, "diRead: i_ino != di_number");
415 		rc = -EIO;
416 	} else if (le32_to_cpu(dp->di_nlink) == 0)
417 		rc = -ESTALE;
418 	else
419 		/* copy the disk inode to the in-memory inode */
420 		rc = copy_from_dinode(dp, ip);
421 
422 	release_metapage(mp);
423 
424 	/* set the ag for the inode */
425 	JFS_IP(ip)->agno = BLKTOAG(agstart, sbi);
426 	JFS_IP(ip)->active_ag = -1;
427 
428 	return (rc);
429 }
430 
431 
432 /*
433  * NAME:        diReadSpecial()
434  *
435  * FUNCTION:    initialize a 'special' inode from disk.
436  *
437  *		this routines handles aggregate level inodes.  The
438  *		inode cache cannot differentiate between the
439  *		aggregate inodes and the filesystem inodes, so we
440  *		handle these here.  We don't actually use the aggregate
441  *	        inode map, since these inodes are at a fixed location
442  *		and in some cases the aggregate inode map isn't initialized
443  *		yet.
444  *
445  * PARAMETERS:
446  *      sb - filesystem superblock
447  *	inum - aggregate inode number
448  *	secondary - 1 if secondary aggregate inode table
449  *
450  * RETURN VALUES:
451  *      new inode	- success
452  *      NULL		- i/o error.
453  */
454 struct inode *diReadSpecial(struct super_block *sb, ino_t inum, int secondary)
455 {
456 	struct jfs_sb_info *sbi = JFS_SBI(sb);
457 	uint address;
458 	struct dinode *dp;
459 	struct inode *ip;
460 	struct metapage *mp;
461 
462 	ip = new_inode(sb);
463 	if (ip == NULL) {
464 		jfs_err("diReadSpecial: new_inode returned NULL!");
465 		return ip;
466 	}
467 
468 	if (secondary) {
469 		address = addressPXD(&sbi->ait2) >> sbi->l2nbperpage;
470 		JFS_IP(ip)->ipimap = sbi->ipaimap2;
471 	} else {
472 		address = AITBL_OFF >> L2PSIZE;
473 		JFS_IP(ip)->ipimap = sbi->ipaimap;
474 	}
475 
476 	ASSERT(inum < INOSPEREXT);
477 
478 	ip->i_ino = inum;
479 
480 	address += inum >> 3;	/* 8 inodes per 4K page */
481 
482 	/* read the page of fixed disk inode (AIT) in raw mode */
483 	mp = read_metapage(ip, address << sbi->l2nbperpage, PSIZE, 1);
484 	if (mp == NULL) {
485 		ip->i_nlink = 1;	/* Don't want iput() deleting it */
486 		iput(ip);
487 		return (NULL);
488 	}
489 
490 	/* get the pointer to the disk inode of interest */
491 	dp = (struct dinode *) (mp->data);
492 	dp += inum % 8;		/* 8 inodes per 4K page */
493 
494 	/* copy on-disk inode to in-memory inode */
495 	if ((copy_from_dinode(dp, ip)) != 0) {
496 		/* handle bad return by returning NULL for ip */
497 		ip->i_nlink = 1;	/* Don't want iput() deleting it */
498 		iput(ip);
499 		/* release the page */
500 		release_metapage(mp);
501 		return (NULL);
502 
503 	}
504 
505 	ip->i_mapping->a_ops = &jfs_aops;
506 	mapping_set_gfp_mask(ip->i_mapping, GFP_NOFS);
507 
508 	/* Allocations to metadata inodes should not affect quotas */
509 	ip->i_flags |= S_NOQUOTA;
510 
511 	if ((inum == FILESYSTEM_I) && (JFS_IP(ip)->ipimap == sbi->ipaimap)) {
512 		sbi->gengen = le32_to_cpu(dp->di_gengen);
513 		sbi->inostamp = le32_to_cpu(dp->di_inostamp);
514 	}
515 
516 	/* release the page */
517 	release_metapage(mp);
518 
519 	return (ip);
520 }
521 
522 /*
523  * NAME:        diWriteSpecial()
524  *
525  * FUNCTION:    Write the special inode to disk
526  *
527  * PARAMETERS:
528  *      ip - special inode
529  *	secondary - 1 if secondary aggregate inode table
530  *
531  * RETURN VALUES: none
532  */
533 
534 void diWriteSpecial(struct inode *ip, int secondary)
535 {
536 	struct jfs_sb_info *sbi = JFS_SBI(ip->i_sb);
537 	uint address;
538 	struct dinode *dp;
539 	ino_t inum = ip->i_ino;
540 	struct metapage *mp;
541 
542 	ip->i_state &= ~I_DIRTY;
543 
544 	if (secondary)
545 		address = addressPXD(&sbi->ait2) >> sbi->l2nbperpage;
546 	else
547 		address = AITBL_OFF >> L2PSIZE;
548 
549 	ASSERT(inum < INOSPEREXT);
550 
551 	address += inum >> 3;	/* 8 inodes per 4K page */
552 
553 	/* read the page of fixed disk inode (AIT) in raw mode */
554 	mp = read_metapage(ip, address << sbi->l2nbperpage, PSIZE, 1);
555 	if (mp == NULL) {
556 		jfs_err("diWriteSpecial: failed to read aggregate inode "
557 			"extent!");
558 		return;
559 	}
560 
561 	/* get the pointer to the disk inode of interest */
562 	dp = (struct dinode *) (mp->data);
563 	dp += inum % 8;		/* 8 inodes per 4K page */
564 
565 	/* copy on-disk inode to in-memory inode */
566 	copy_to_dinode(dp, ip);
567 	memcpy(&dp->di_xtroot, &JFS_IP(ip)->i_xtroot, 288);
568 
569 	if (inum == FILESYSTEM_I)
570 		dp->di_gengen = cpu_to_le32(sbi->gengen);
571 
572 	/* write the page */
573 	write_metapage(mp);
574 }
575 
576 /*
577  * NAME:        diFreeSpecial()
578  *
579  * FUNCTION:    Free allocated space for special inode
580  */
581 void diFreeSpecial(struct inode *ip)
582 {
583 	if (ip == NULL) {
584 		jfs_err("diFreeSpecial called with NULL ip!");
585 		return;
586 	}
587 	filemap_fdatawrite(ip->i_mapping);
588 	filemap_fdatawait(ip->i_mapping);
589 	truncate_inode_pages(ip->i_mapping, 0);
590 	iput(ip);
591 }
592 
593 
594 
595 /*
596  * NAME:        diWrite()
597  *
598  * FUNCTION:    write the on-disk inode portion of the in-memory inode
599  *		to its corresponding on-disk inode.
600  *
601  *		on entry, the specifed incore inode should itself
602  *		specify the disk inode number corresponding to the
603  *		incore inode (i.e. i_number should be initialized).
604  *
605  *		the inode contains the inode extent address for the disk
606  *		inode.  with the inode extent address in hand, the
607  *		page of the extent that contains the disk inode is
608  *		read and the disk inode portion of the incore inode
609  *		is copied to the disk inode.
610  *
611  * PARAMETERS:
612  *	tid -  transacation id
613  *      ip  -  pointer to incore inode to be written to the inode extent.
614  *
615  * RETURN VALUES:
616  *      0       - success
617  *      -EIO  	- i/o error.
618  */
619 int diWrite(tid_t tid, struct inode *ip)
620 {
621 	struct jfs_sb_info *sbi = JFS_SBI(ip->i_sb);
622 	struct jfs_inode_info *jfs_ip = JFS_IP(ip);
623 	int rc = 0;
624 	s32 ino;
625 	struct dinode *dp;
626 	s64 blkno;
627 	int block_offset;
628 	int inodes_left;
629 	struct metapage *mp;
630 	uint pageno;
631 	int rel_inode;
632 	int dioffset;
633 	struct inode *ipimap;
634 	uint type;
635 	lid_t lid;
636 	struct tlock *ditlck, *tlck;
637 	struct linelock *dilinelock, *ilinelock;
638 	struct lv *lv;
639 	int n;
640 
641 	ipimap = jfs_ip->ipimap;
642 
643 	ino = ip->i_ino & (INOSPERIAG - 1);
644 
645 	if (!addressPXD(&(jfs_ip->ixpxd)) ||
646 	    (lengthPXD(&(jfs_ip->ixpxd)) !=
647 	     JFS_IP(ipimap)->i_imap->im_nbperiext)) {
648 		jfs_error(ip->i_sb, "diWrite: ixpxd invalid");
649 		return -EIO;
650 	}
651 
652 	/*
653 	 * read the page of disk inode containing the specified inode:
654 	 */
655 	/* compute the block address of the page */
656 	blkno = INOPBLK(&(jfs_ip->ixpxd), ino, sbi->l2nbperpage);
657 
658 	rel_inode = (ino & (INOSPERPAGE - 1));
659 	pageno = blkno >> sbi->l2nbperpage;
660 
661 	if ((block_offset = ((u32) blkno & (sbi->nbperpage - 1)))) {
662 		/*
663 		 * OS/2 didn't always align inode extents on page boundaries
664 		 */
665 		inodes_left =
666 		    (sbi->nbperpage - block_offset) << sbi->l2niperblk;
667 
668 		if (rel_inode < inodes_left)
669 			rel_inode += block_offset << sbi->l2niperblk;
670 		else {
671 			pageno += 1;
672 			rel_inode -= inodes_left;
673 		}
674 	}
675 	/* read the page of disk inode */
676       retry:
677 	mp = read_metapage(ipimap, pageno << sbi->l2nbperpage, PSIZE, 1);
678 	if (mp == 0)
679 		return -EIO;
680 
681 	/* get the pointer to the disk inode */
682 	dp = (struct dinode *) mp->data;
683 	dp += rel_inode;
684 
685 	dioffset = (ino & (INOSPERPAGE - 1)) << L2DISIZE;
686 
687 	/*
688 	 * acquire transaction lock on the on-disk inode;
689 	 * N.B. tlock is acquired on ipimap not ip;
690 	 */
691 	if ((ditlck =
692 	     txLock(tid, ipimap, mp, tlckINODE | tlckENTRY)) == NULL)
693 		goto retry;
694 	dilinelock = (struct linelock *) & ditlck->lock;
695 
696 	/*
697 	 * copy btree root from in-memory inode to on-disk inode
698 	 *
699 	 * (tlock is taken from inline B+-tree root in in-memory
700 	 * inode when the B+-tree root is updated, which is pointed
701 	 * by jfs_ip->blid as well as being on tx tlock list)
702 	 *
703 	 * further processing of btree root is based on the copy
704 	 * in in-memory inode, where txLog() will log from, and,
705 	 * for xtree root, txUpdateMap() will update map and reset
706 	 * XAD_NEW bit;
707 	 */
708 
709 	if (S_ISDIR(ip->i_mode) && (lid = jfs_ip->xtlid)) {
710 		/*
711 		 * This is the special xtree inside the directory for storing
712 		 * the directory table
713 		 */
714 		xtpage_t *p, *xp;
715 		xad_t *xad;
716 
717 		jfs_ip->xtlid = 0;
718 		tlck = lid_to_tlock(lid);
719 		assert(tlck->type & tlckXTREE);
720 		tlck->type |= tlckBTROOT;
721 		tlck->mp = mp;
722 		ilinelock = (struct linelock *) & tlck->lock;
723 
724 		/*
725 		 * copy xtree root from inode to dinode:
726 		 */
727 		p = &jfs_ip->i_xtroot;
728 		xp = (xtpage_t *) &dp->di_dirtable;
729 		lv = ilinelock->lv;
730 		for (n = 0; n < ilinelock->index; n++, lv++) {
731 			memcpy(&xp->xad[lv->offset], &p->xad[lv->offset],
732 			       lv->length << L2XTSLOTSIZE);
733 		}
734 
735 		/* reset on-disk (metadata page) xtree XAD_NEW bit */
736 		xad = &xp->xad[XTENTRYSTART];
737 		for (n = XTENTRYSTART;
738 		     n < le16_to_cpu(xp->header.nextindex); n++, xad++)
739 			if (xad->flag & (XAD_NEW | XAD_EXTENDED))
740 				xad->flag &= ~(XAD_NEW | XAD_EXTENDED);
741 	}
742 
743 	if ((lid = jfs_ip->blid) == 0)
744 		goto inlineData;
745 	jfs_ip->blid = 0;
746 
747 	tlck = lid_to_tlock(lid);
748 	type = tlck->type;
749 	tlck->type |= tlckBTROOT;
750 	tlck->mp = mp;
751 	ilinelock = (struct linelock *) & tlck->lock;
752 
753 	/*
754 	 *      regular file: 16 byte (XAD slot) granularity
755 	 */
756 	if (type & tlckXTREE) {
757 		xtpage_t *p, *xp;
758 		xad_t *xad;
759 
760 		/*
761 		 * copy xtree root from inode to dinode:
762 		 */
763 		p = &jfs_ip->i_xtroot;
764 		xp = &dp->di_xtroot;
765 		lv = ilinelock->lv;
766 		for (n = 0; n < ilinelock->index; n++, lv++) {
767 			memcpy(&xp->xad[lv->offset], &p->xad[lv->offset],
768 			       lv->length << L2XTSLOTSIZE);
769 		}
770 
771 		/* reset on-disk (metadata page) xtree XAD_NEW bit */
772 		xad = &xp->xad[XTENTRYSTART];
773 		for (n = XTENTRYSTART;
774 		     n < le16_to_cpu(xp->header.nextindex); n++, xad++)
775 			if (xad->flag & (XAD_NEW | XAD_EXTENDED))
776 				xad->flag &= ~(XAD_NEW | XAD_EXTENDED);
777 	}
778 	/*
779 	 *      directory: 32 byte (directory entry slot) granularity
780 	 */
781 	else if (type & tlckDTREE) {
782 		dtpage_t *p, *xp;
783 
784 		/*
785 		 * copy dtree root from inode to dinode:
786 		 */
787 		p = (dtpage_t *) &jfs_ip->i_dtroot;
788 		xp = (dtpage_t *) & dp->di_dtroot;
789 		lv = ilinelock->lv;
790 		for (n = 0; n < ilinelock->index; n++, lv++) {
791 			memcpy(&xp->slot[lv->offset], &p->slot[lv->offset],
792 			       lv->length << L2DTSLOTSIZE);
793 		}
794 	} else {
795 		jfs_err("diWrite: UFO tlock");
796 	}
797 
798       inlineData:
799 	/*
800 	 * copy inline symlink from in-memory inode to on-disk inode
801 	 */
802 	if (S_ISLNK(ip->i_mode) && ip->i_size < IDATASIZE) {
803 		lv = & dilinelock->lv[dilinelock->index];
804 		lv->offset = (dioffset + 2 * 128) >> L2INODESLOTSIZE;
805 		lv->length = 2;
806 		memcpy(&dp->di_fastsymlink, jfs_ip->i_inline, IDATASIZE);
807 		dilinelock->index++;
808 	}
809 	/*
810 	 * copy inline data from in-memory inode to on-disk inode:
811 	 * 128 byte slot granularity
812 	 */
813 	if (test_cflag(COMMIT_Inlineea, ip)) {
814 		lv = & dilinelock->lv[dilinelock->index];
815 		lv->offset = (dioffset + 3 * 128) >> L2INODESLOTSIZE;
816 		lv->length = 1;
817 		memcpy(&dp->di_inlineea, jfs_ip->i_inline_ea, INODESLOTSIZE);
818 		dilinelock->index++;
819 
820 		clear_cflag(COMMIT_Inlineea, ip);
821 	}
822 
823 	/*
824 	 *      lock/copy inode base: 128 byte slot granularity
825 	 */
826 // baseDinode:
827 	lv = & dilinelock->lv[dilinelock->index];
828 	lv->offset = dioffset >> L2INODESLOTSIZE;
829 	copy_to_dinode(dp, ip);
830 	if (test_and_clear_cflag(COMMIT_Dirtable, ip)) {
831 		lv->length = 2;
832 		memcpy(&dp->di_dirtable, &jfs_ip->i_dirtable, 96);
833 	} else
834 		lv->length = 1;
835 	dilinelock->index++;
836 
837 #ifdef _JFS_FASTDASD
838 	/*
839 	 * We aren't logging changes to the DASD used in directory inodes,
840 	 * but we need to write them to disk.  If we don't unmount cleanly,
841 	 * mount will recalculate the DASD used.
842 	 */
843 	if (S_ISDIR(ip->i_mode)
844 	    && (ip->i_ipmnt->i_mntflag & JFS_DASD_ENABLED))
845 		memcpy(&dp->di_DASD, &ip->i_DASD, sizeof(struct dasd));
846 #endif				/*  _JFS_FASTDASD */
847 
848 	/* release the buffer holding the updated on-disk inode.
849 	 * the buffer will be later written by commit processing.
850 	 */
851 	write_metapage(mp);
852 
853 	return (rc);
854 }
855 
856 
857 /*
858  * NAME:        diFree(ip)
859  *
860  * FUNCTION:    free a specified inode from the inode working map
861  *		for a fileset or aggregate.
862  *
863  *		if the inode to be freed represents the first (only)
864  *		free inode within the iag, the iag will be placed on
865  *		the ag free inode list.
866  *
867  *		freeing the inode will cause the inode extent to be
868  *		freed if the inode is the only allocated inode within
869  *		the extent.  in this case all the disk resource backing
870  *		up the inode extent will be freed. in addition, the iag
871  *		will be placed on the ag extent free list if the extent
872  *		is the first free extent in the iag.  if freeing the
873  *		extent also means that no free inodes will exist for
874  *		the iag, the iag will also be removed from the ag free
875  *		inode list.
876  *
877  *		the iag describing the inode will be freed if the extent
878  *		is to be freed and it is the only backed extent within
879  *		the iag.  in this case, the iag will be removed from the
880  *		ag free extent list and ag free inode list and placed on
881  *		the inode map's free iag list.
882  *
883  *		a careful update approach is used to provide consistency
884  *		in the face of updates to multiple buffers.  under this
885  *		approach, all required buffers are obtained before making
886  *		any updates and are held until all updates are complete.
887  *
888  * PARAMETERS:
889  *      ip  	- inode to be freed.
890  *
891  * RETURN VALUES:
892  *      0       - success
893  *      -EIO  	- i/o error.
894  */
895 int diFree(struct inode *ip)
896 {
897 	int rc;
898 	ino_t inum = ip->i_ino;
899 	struct iag *iagp, *aiagp, *biagp, *ciagp, *diagp;
900 	struct metapage *mp, *amp, *bmp, *cmp, *dmp;
901 	int iagno, ino, extno, bitno, sword, agno;
902 	int back, fwd;
903 	u32 bitmap, mask;
904 	struct inode *ipimap = JFS_SBI(ip->i_sb)->ipimap;
905 	struct inomap *imap = JFS_IP(ipimap)->i_imap;
906 	pxd_t freepxd;
907 	tid_t tid;
908 	struct inode *iplist[3];
909 	struct tlock *tlck;
910 	struct pxd_lock *pxdlock;
911 
912 	/*
913 	 * This is just to suppress compiler warnings.  The same logic that
914 	 * references these variables is used to initialize them.
915 	 */
916 	aiagp = biagp = ciagp = diagp = NULL;
917 
918 	/* get the iag number containing the inode.
919 	 */
920 	iagno = INOTOIAG(inum);
921 
922 	/* make sure that the iag is contained within
923 	 * the map.
924 	 */
925 	if (iagno >= imap->im_nextiag) {
926 		dump_mem("imap", imap, 32);
927 		jfs_error(ip->i_sb,
928 			  "diFree: inum = %d, iagno = %d, nextiag = %d",
929 			  (uint) inum, iagno, imap->im_nextiag);
930 		return -EIO;
931 	}
932 
933 	/* get the allocation group for this ino.
934 	 */
935 	agno = JFS_IP(ip)->agno;
936 
937 	/* Lock the AG specific inode map information
938 	 */
939 	AG_LOCK(imap, agno);
940 
941 	/* Obtain read lock in imap inode.  Don't release it until we have
942 	 * read all of the IAG's that we are going to.
943 	 */
944 	IREAD_LOCK(ipimap);
945 
946 	/* read the iag.
947 	 */
948 	if ((rc = diIAGRead(imap, iagno, &mp))) {
949 		IREAD_UNLOCK(ipimap);
950 		AG_UNLOCK(imap, agno);
951 		return (rc);
952 	}
953 	iagp = (struct iag *) mp->data;
954 
955 	/* get the inode number and extent number of the inode within
956 	 * the iag and the inode number within the extent.
957 	 */
958 	ino = inum & (INOSPERIAG - 1);
959 	extno = ino >> L2INOSPEREXT;
960 	bitno = ino & (INOSPEREXT - 1);
961 	mask = HIGHORDER >> bitno;
962 
963 	if (!(le32_to_cpu(iagp->wmap[extno]) & mask)) {
964 		jfs_error(ip->i_sb,
965 			  "diFree: wmap shows inode already free");
966 	}
967 
968 	if (!addressPXD(&iagp->inoext[extno])) {
969 		release_metapage(mp);
970 		IREAD_UNLOCK(ipimap);
971 		AG_UNLOCK(imap, agno);
972 		jfs_error(ip->i_sb, "diFree: invalid inoext");
973 		return -EIO;
974 	}
975 
976 	/* compute the bitmap for the extent reflecting the freed inode.
977 	 */
978 	bitmap = le32_to_cpu(iagp->wmap[extno]) & ~mask;
979 
980 	if (imap->im_agctl[agno].numfree > imap->im_agctl[agno].numinos) {
981 		release_metapage(mp);
982 		IREAD_UNLOCK(ipimap);
983 		AG_UNLOCK(imap, agno);
984 		jfs_error(ip->i_sb, "diFree: numfree > numinos");
985 		return -EIO;
986 	}
987 	/*
988 	 *      inode extent still has some inodes or below low water mark:
989 	 *      keep the inode extent;
990 	 */
991 	if (bitmap ||
992 	    imap->im_agctl[agno].numfree < 96 ||
993 	    (imap->im_agctl[agno].numfree < 288 &&
994 	     (((imap->im_agctl[agno].numfree * 100) /
995 	       imap->im_agctl[agno].numinos) <= 25))) {
996 		/* if the iag currently has no free inodes (i.e.,
997 		 * the inode being freed is the first free inode of iag),
998 		 * insert the iag at head of the inode free list for the ag.
999 		 */
1000 		if (iagp->nfreeinos == 0) {
1001 			/* check if there are any iags on the ag inode
1002 			 * free list.  if so, read the first one so that
1003 			 * we can link the current iag onto the list at
1004 			 * the head.
1005 			 */
1006 			if ((fwd = imap->im_agctl[agno].inofree) >= 0) {
1007 				/* read the iag that currently is the head
1008 				 * of the list.
1009 				 */
1010 				if ((rc = diIAGRead(imap, fwd, &amp))) {
1011 					IREAD_UNLOCK(ipimap);
1012 					AG_UNLOCK(imap, agno);
1013 					release_metapage(mp);
1014 					return (rc);
1015 				}
1016 				aiagp = (struct iag *) amp->data;
1017 
1018 				/* make current head point back to the iag.
1019 				 */
1020 				aiagp->inofreeback = cpu_to_le32(iagno);
1021 
1022 				write_metapage(amp);
1023 			}
1024 
1025 			/* iag points forward to current head and iag
1026 			 * becomes the new head of the list.
1027 			 */
1028 			iagp->inofreefwd =
1029 			    cpu_to_le32(imap->im_agctl[agno].inofree);
1030 			iagp->inofreeback = cpu_to_le32(-1);
1031 			imap->im_agctl[agno].inofree = iagno;
1032 		}
1033 		IREAD_UNLOCK(ipimap);
1034 
1035 		/* update the free inode summary map for the extent if
1036 		 * freeing the inode means the extent will now have free
1037 		 * inodes (i.e., the inode being freed is the first free
1038 		 * inode of extent),
1039 		 */
1040 		if (iagp->wmap[extno] == cpu_to_le32(ONES)) {
1041 			sword = extno >> L2EXTSPERSUM;
1042 			bitno = extno & (EXTSPERSUM - 1);
1043 			iagp->inosmap[sword] &=
1044 			    cpu_to_le32(~(HIGHORDER >> bitno));
1045 		}
1046 
1047 		/* update the bitmap.
1048 		 */
1049 		iagp->wmap[extno] = cpu_to_le32(bitmap);
1050 		DBG_DIFREE(imap, inum);
1051 
1052 		/* update the free inode counts at the iag, ag and
1053 		 * map level.
1054 		 */
1055 		iagp->nfreeinos =
1056 		    cpu_to_le32(le32_to_cpu(iagp->nfreeinos) + 1);
1057 		imap->im_agctl[agno].numfree += 1;
1058 		atomic_inc(&imap->im_numfree);
1059 
1060 		/* release the AG inode map lock
1061 		 */
1062 		AG_UNLOCK(imap, agno);
1063 
1064 		/* write the iag */
1065 		write_metapage(mp);
1066 
1067 		return (0);
1068 	}
1069 
1070 
1071 	/*
1072 	 *      inode extent has become free and above low water mark:
1073 	 *      free the inode extent;
1074 	 */
1075 
1076 	/*
1077 	 *      prepare to update iag list(s) (careful update step 1)
1078 	 */
1079 	amp = bmp = cmp = dmp = NULL;
1080 	fwd = back = -1;
1081 
1082 	/* check if the iag currently has no free extents.  if so,
1083 	 * it will be placed on the head of the ag extent free list.
1084 	 */
1085 	if (iagp->nfreeexts == 0) {
1086 		/* check if the ag extent free list has any iags.
1087 		 * if so, read the iag at the head of the list now.
1088 		 * this (head) iag will be updated later to reflect
1089 		 * the addition of the current iag at the head of
1090 		 * the list.
1091 		 */
1092 		if ((fwd = imap->im_agctl[agno].extfree) >= 0) {
1093 			if ((rc = diIAGRead(imap, fwd, &amp)))
1094 				goto error_out;
1095 			aiagp = (struct iag *) amp->data;
1096 		}
1097 	} else {
1098 		/* iag has free extents. check if the addition of a free
1099 		 * extent will cause all extents to be free within this
1100 		 * iag.  if so, the iag will be removed from the ag extent
1101 		 * free list and placed on the inode map's free iag list.
1102 		 */
1103 		if (iagp->nfreeexts == cpu_to_le32(EXTSPERIAG - 1)) {
1104 			/* in preparation for removing the iag from the
1105 			 * ag extent free list, read the iags preceeding
1106 			 * and following the iag on the ag extent free
1107 			 * list.
1108 			 */
1109 			if ((fwd = le32_to_cpu(iagp->extfreefwd)) >= 0) {
1110 				if ((rc = diIAGRead(imap, fwd, &amp)))
1111 					goto error_out;
1112 				aiagp = (struct iag *) amp->data;
1113 			}
1114 
1115 			if ((back = le32_to_cpu(iagp->extfreeback)) >= 0) {
1116 				if ((rc = diIAGRead(imap, back, &bmp)))
1117 					goto error_out;
1118 				biagp = (struct iag *) bmp->data;
1119 			}
1120 		}
1121 	}
1122 
1123 	/* remove the iag from the ag inode free list if freeing
1124 	 * this extent cause the iag to have no free inodes.
1125 	 */
1126 	if (iagp->nfreeinos == cpu_to_le32(INOSPEREXT - 1)) {
1127 		int inofreeback = le32_to_cpu(iagp->inofreeback);
1128 		int inofreefwd = le32_to_cpu(iagp->inofreefwd);
1129 
1130 		/* in preparation for removing the iag from the
1131 		 * ag inode free list, read the iags preceeding
1132 		 * and following the iag on the ag inode free
1133 		 * list.  before reading these iags, we must make
1134 		 * sure that we already don't have them in hand
1135 		 * from up above, since re-reading an iag (buffer)
1136 		 * we are currently holding would cause a deadlock.
1137 		 */
1138 		if (inofreefwd >= 0) {
1139 
1140 			if (inofreefwd == fwd)
1141 				ciagp = (struct iag *) amp->data;
1142 			else if (inofreefwd == back)
1143 				ciagp = (struct iag *) bmp->data;
1144 			else {
1145 				if ((rc =
1146 				     diIAGRead(imap, inofreefwd, &cmp)))
1147 					goto error_out;
1148 				ciagp = (struct iag *) cmp->data;
1149 			}
1150 			assert(ciagp != NULL);
1151 		}
1152 
1153 		if (inofreeback >= 0) {
1154 			if (inofreeback == fwd)
1155 				diagp = (struct iag *) amp->data;
1156 			else if (inofreeback == back)
1157 				diagp = (struct iag *) bmp->data;
1158 			else {
1159 				if ((rc =
1160 				     diIAGRead(imap, inofreeback, &dmp)))
1161 					goto error_out;
1162 				diagp = (struct iag *) dmp->data;
1163 			}
1164 			assert(diagp != NULL);
1165 		}
1166 	}
1167 
1168 	IREAD_UNLOCK(ipimap);
1169 
1170 	/*
1171 	 * invalidate any page of the inode extent freed from buffer cache;
1172 	 */
1173 	freepxd = iagp->inoext[extno];
1174 	invalidate_pxd_metapages(ip, freepxd);
1175 
1176 	/*
1177 	 *      update iag list(s) (careful update step 2)
1178 	 */
1179 	/* add the iag to the ag extent free list if this is the
1180 	 * first free extent for the iag.
1181 	 */
1182 	if (iagp->nfreeexts == 0) {
1183 		if (fwd >= 0)
1184 			aiagp->extfreeback = cpu_to_le32(iagno);
1185 
1186 		iagp->extfreefwd =
1187 		    cpu_to_le32(imap->im_agctl[agno].extfree);
1188 		iagp->extfreeback = cpu_to_le32(-1);
1189 		imap->im_agctl[agno].extfree = iagno;
1190 	} else {
1191 		/* remove the iag from the ag extent list if all extents
1192 		 * are now free and place it on the inode map iag free list.
1193 		 */
1194 		if (iagp->nfreeexts == cpu_to_le32(EXTSPERIAG - 1)) {
1195 			if (fwd >= 0)
1196 				aiagp->extfreeback = iagp->extfreeback;
1197 
1198 			if (back >= 0)
1199 				biagp->extfreefwd = iagp->extfreefwd;
1200 			else
1201 				imap->im_agctl[agno].extfree =
1202 				    le32_to_cpu(iagp->extfreefwd);
1203 
1204 			iagp->extfreefwd = iagp->extfreeback = cpu_to_le32(-1);
1205 
1206 			IAGFREE_LOCK(imap);
1207 			iagp->iagfree = cpu_to_le32(imap->im_freeiag);
1208 			imap->im_freeiag = iagno;
1209 			IAGFREE_UNLOCK(imap);
1210 		}
1211 	}
1212 
1213 	/* remove the iag from the ag inode free list if freeing
1214 	 * this extent causes the iag to have no free inodes.
1215 	 */
1216 	if (iagp->nfreeinos == cpu_to_le32(INOSPEREXT - 1)) {
1217 		if ((int) le32_to_cpu(iagp->inofreefwd) >= 0)
1218 			ciagp->inofreeback = iagp->inofreeback;
1219 
1220 		if ((int) le32_to_cpu(iagp->inofreeback) >= 0)
1221 			diagp->inofreefwd = iagp->inofreefwd;
1222 		else
1223 			imap->im_agctl[agno].inofree =
1224 			    le32_to_cpu(iagp->inofreefwd);
1225 
1226 		iagp->inofreefwd = iagp->inofreeback = cpu_to_le32(-1);
1227 	}
1228 
1229 	/* update the inode extent address and working map
1230 	 * to reflect the free extent.
1231 	 * the permanent map should have been updated already
1232 	 * for the inode being freed.
1233 	 */
1234 	if (iagp->pmap[extno] != 0) {
1235 		jfs_error(ip->i_sb, "diFree: the pmap does not show inode free");
1236 	}
1237 	iagp->wmap[extno] = 0;
1238 	DBG_DIFREE(imap, inum);
1239 	PXDlength(&iagp->inoext[extno], 0);
1240 	PXDaddress(&iagp->inoext[extno], 0);
1241 
1242 	/* update the free extent and free inode summary maps
1243 	 * to reflect the freed extent.
1244 	 * the inode summary map is marked to indicate no inodes
1245 	 * available for the freed extent.
1246 	 */
1247 	sword = extno >> L2EXTSPERSUM;
1248 	bitno = extno & (EXTSPERSUM - 1);
1249 	mask = HIGHORDER >> bitno;
1250 	iagp->inosmap[sword] |= cpu_to_le32(mask);
1251 	iagp->extsmap[sword] &= cpu_to_le32(~mask);
1252 
1253 	/* update the number of free inodes and number of free extents
1254 	 * for the iag.
1255 	 */
1256 	iagp->nfreeinos = cpu_to_le32(le32_to_cpu(iagp->nfreeinos) -
1257 				      (INOSPEREXT - 1));
1258 	iagp->nfreeexts = cpu_to_le32(le32_to_cpu(iagp->nfreeexts) + 1);
1259 
1260 	/* update the number of free inodes and backed inodes
1261 	 * at the ag and inode map level.
1262 	 */
1263 	imap->im_agctl[agno].numfree -= (INOSPEREXT - 1);
1264 	imap->im_agctl[agno].numinos -= INOSPEREXT;
1265 	atomic_sub(INOSPEREXT - 1, &imap->im_numfree);
1266 	atomic_sub(INOSPEREXT, &imap->im_numinos);
1267 
1268 	if (amp)
1269 		write_metapage(amp);
1270 	if (bmp)
1271 		write_metapage(bmp);
1272 	if (cmp)
1273 		write_metapage(cmp);
1274 	if (dmp)
1275 		write_metapage(dmp);
1276 
1277 	/*
1278 	 * start transaction to update block allocation map
1279 	 * for the inode extent freed;
1280 	 *
1281 	 * N.B. AG_LOCK is released and iag will be released below, and
1282 	 * other thread may allocate inode from/reusing the ixad freed
1283 	 * BUT with new/different backing inode extent from the extent
1284 	 * to be freed by the transaction;
1285 	 */
1286 	tid = txBegin(ipimap->i_sb, COMMIT_FORCE);
1287 	down(&JFS_IP(ipimap)->commit_sem);
1288 
1289 	/* acquire tlock of the iag page of the freed ixad
1290 	 * to force the page NOHOMEOK (even though no data is
1291 	 * logged from the iag page) until NOREDOPAGE|FREEXTENT log
1292 	 * for the free of the extent is committed;
1293 	 * write FREEXTENT|NOREDOPAGE log record
1294 	 * N.B. linelock is overlaid as freed extent descriptor;
1295 	 */
1296 	tlck = txLock(tid, ipimap, mp, tlckINODE | tlckFREE);
1297 	pxdlock = (struct pxd_lock *) & tlck->lock;
1298 	pxdlock->flag = mlckFREEPXD;
1299 	pxdlock->pxd = freepxd;
1300 	pxdlock->index = 1;
1301 
1302 	write_metapage(mp);
1303 
1304 	iplist[0] = ipimap;
1305 
1306 	/*
1307 	 * logredo needs the IAG number and IAG extent index in order
1308 	 * to ensure that the IMap is consistent.  The least disruptive
1309 	 * way to pass these values through  to the transaction manager
1310 	 * is in the iplist array.
1311 	 *
1312 	 * It's not pretty, but it works.
1313 	 */
1314 	iplist[1] = (struct inode *) (size_t)iagno;
1315 	iplist[2] = (struct inode *) (size_t)extno;
1316 
1317 	rc = txCommit(tid, 1, &iplist[0], COMMIT_FORCE);
1318 
1319 	txEnd(tid);
1320 	up(&JFS_IP(ipimap)->commit_sem);
1321 
1322 	/* unlock the AG inode map information */
1323 	AG_UNLOCK(imap, agno);
1324 
1325 	return (0);
1326 
1327       error_out:
1328 	IREAD_UNLOCK(ipimap);
1329 
1330 	if (amp)
1331 		release_metapage(amp);
1332 	if (bmp)
1333 		release_metapage(bmp);
1334 	if (cmp)
1335 		release_metapage(cmp);
1336 	if (dmp)
1337 		release_metapage(dmp);
1338 
1339 	AG_UNLOCK(imap, agno);
1340 
1341 	release_metapage(mp);
1342 
1343 	return (rc);
1344 }
1345 
1346 /*
1347  * There are several places in the diAlloc* routines where we initialize
1348  * the inode.
1349  */
1350 static inline void
1351 diInitInode(struct inode *ip, int iagno, int ino, int extno, struct iag * iagp)
1352 {
1353 	struct jfs_sb_info *sbi = JFS_SBI(ip->i_sb);
1354 	struct jfs_inode_info *jfs_ip = JFS_IP(ip);
1355 
1356 	ip->i_ino = (iagno << L2INOSPERIAG) + ino;
1357 	DBG_DIALLOC(JFS_IP(ipimap)->i_imap, ip->i_ino);
1358 	jfs_ip->ixpxd = iagp->inoext[extno];
1359 	jfs_ip->agno = BLKTOAG(le64_to_cpu(iagp->agstart), sbi);
1360 	jfs_ip->active_ag = -1;
1361 }
1362 
1363 
1364 /*
1365  * NAME:        diAlloc(pip,dir,ip)
1366  *
1367  * FUNCTION:    allocate a disk inode from the inode working map
1368  *		for a fileset or aggregate.
1369  *
1370  * PARAMETERS:
1371  *      pip  	- pointer to incore inode for the parent inode.
1372  *      dir  	- TRUE if the new disk inode is for a directory.
1373  *      ip  	- pointer to a new inode
1374  *
1375  * RETURN VALUES:
1376  *      0       - success.
1377  *      -ENOSPC	- insufficient disk resources.
1378  *      -EIO  	- i/o error.
1379  */
1380 int diAlloc(struct inode *pip, boolean_t dir, struct inode *ip)
1381 {
1382 	int rc, ino, iagno, addext, extno, bitno, sword;
1383 	int nwords, rem, i, agno;
1384 	u32 mask, inosmap, extsmap;
1385 	struct inode *ipimap;
1386 	struct metapage *mp;
1387 	ino_t inum;
1388 	struct iag *iagp;
1389 	struct inomap *imap;
1390 
1391 	/* get the pointers to the inode map inode and the
1392 	 * corresponding imap control structure.
1393 	 */
1394 	ipimap = JFS_SBI(pip->i_sb)->ipimap;
1395 	imap = JFS_IP(ipimap)->i_imap;
1396 	JFS_IP(ip)->ipimap = ipimap;
1397 	JFS_IP(ip)->fileset = FILESYSTEM_I;
1398 
1399 	/* for a directory, the allocation policy is to start
1400 	 * at the ag level using the preferred ag.
1401 	 */
1402 	if (dir == TRUE) {
1403 		agno = dbNextAG(JFS_SBI(pip->i_sb)->ipbmap);
1404 		AG_LOCK(imap, agno);
1405 		goto tryag;
1406 	}
1407 
1408 	/* for files, the policy starts off by trying to allocate from
1409 	 * the same iag containing the parent disk inode:
1410 	 * try to allocate the new disk inode close to the parent disk
1411 	 * inode, using parent disk inode number + 1 as the allocation
1412 	 * hint.  (we use a left-to-right policy to attempt to avoid
1413 	 * moving backward on the disk.)  compute the hint within the
1414 	 * file system and the iag.
1415 	 */
1416 
1417 	/* get the ag number of this iag */
1418 	agno = JFS_IP(pip)->agno;
1419 
1420 	if (atomic_read(&JFS_SBI(pip->i_sb)->bmap->db_active[agno])) {
1421 		/*
1422 		 * There is an open file actively growing.  We want to
1423 		 * allocate new inodes from a different ag to avoid
1424 		 * fragmentation problems.
1425 		 */
1426 		agno = dbNextAG(JFS_SBI(pip->i_sb)->ipbmap);
1427 		AG_LOCK(imap, agno);
1428 		goto tryag;
1429 	}
1430 
1431 	inum = pip->i_ino + 1;
1432 	ino = inum & (INOSPERIAG - 1);
1433 
1434 	/* back off the the hint if it is outside of the iag */
1435 	if (ino == 0)
1436 		inum = pip->i_ino;
1437 
1438 	/* lock the AG inode map information */
1439 	AG_LOCK(imap, agno);
1440 
1441 	/* Get read lock on imap inode */
1442 	IREAD_LOCK(ipimap);
1443 
1444 	/* get the iag number and read the iag */
1445 	iagno = INOTOIAG(inum);
1446 	if ((rc = diIAGRead(imap, iagno, &mp))) {
1447 		IREAD_UNLOCK(ipimap);
1448 		AG_UNLOCK(imap, agno);
1449 		return (rc);
1450 	}
1451 	iagp = (struct iag *) mp->data;
1452 
1453 	/* determine if new inode extent is allowed to be added to the iag.
1454 	 * new inode extent can be added to the iag if the ag
1455 	 * has less than 32 free disk inodes and the iag has free extents.
1456 	 */
1457 	addext = (imap->im_agctl[agno].numfree < 32 && iagp->nfreeexts);
1458 
1459 	/*
1460 	 *      try to allocate from the IAG
1461 	 */
1462 	/* check if the inode may be allocated from the iag
1463 	 * (i.e. the inode has free inodes or new extent can be added).
1464 	 */
1465 	if (iagp->nfreeinos || addext) {
1466 		/* determine the extent number of the hint.
1467 		 */
1468 		extno = ino >> L2INOSPEREXT;
1469 
1470 		/* check if the extent containing the hint has backed
1471 		 * inodes.  if so, try to allocate within this extent.
1472 		 */
1473 		if (addressPXD(&iagp->inoext[extno])) {
1474 			bitno = ino & (INOSPEREXT - 1);
1475 			if ((bitno =
1476 			     diFindFree(le32_to_cpu(iagp->wmap[extno]),
1477 					bitno))
1478 			    < INOSPEREXT) {
1479 				ino = (extno << L2INOSPEREXT) + bitno;
1480 
1481 				/* a free inode (bit) was found within this
1482 				 * extent, so allocate it.
1483 				 */
1484 				rc = diAllocBit(imap, iagp, ino);
1485 				IREAD_UNLOCK(ipimap);
1486 				if (rc) {
1487 					assert(rc == -EIO);
1488 				} else {
1489 					/* set the results of the allocation
1490 					 * and write the iag.
1491 					 */
1492 					diInitInode(ip, iagno, ino, extno,
1493 						    iagp);
1494 					mark_metapage_dirty(mp);
1495 				}
1496 				release_metapage(mp);
1497 
1498 				/* free the AG lock and return.
1499 				 */
1500 				AG_UNLOCK(imap, agno);
1501 				return (rc);
1502 			}
1503 
1504 			if (!addext)
1505 				extno =
1506 				    (extno ==
1507 				     EXTSPERIAG - 1) ? 0 : extno + 1;
1508 		}
1509 
1510 		/*
1511 		 * no free inodes within the extent containing the hint.
1512 		 *
1513 		 * try to allocate from the backed extents following
1514 		 * hint or, if appropriate (i.e. addext is true), allocate
1515 		 * an extent of free inodes at or following the extent
1516 		 * containing the hint.
1517 		 *
1518 		 * the free inode and free extent summary maps are used
1519 		 * here, so determine the starting summary map position
1520 		 * and the number of words we'll have to examine.  again,
1521 		 * the approach is to allocate following the hint, so we
1522 		 * might have to initially ignore prior bits of the summary
1523 		 * map that represent extents prior to the extent containing
1524 		 * the hint and later revisit these bits.
1525 		 */
1526 		bitno = extno & (EXTSPERSUM - 1);
1527 		nwords = (bitno == 0) ? SMAPSZ : SMAPSZ + 1;
1528 		sword = extno >> L2EXTSPERSUM;
1529 
1530 		/* mask any prior bits for the starting words of the
1531 		 * summary map.
1532 		 */
1533 		mask = ONES << (EXTSPERSUM - bitno);
1534 		inosmap = le32_to_cpu(iagp->inosmap[sword]) | mask;
1535 		extsmap = le32_to_cpu(iagp->extsmap[sword]) | mask;
1536 
1537 		/* scan the free inode and free extent summary maps for
1538 		 * free resources.
1539 		 */
1540 		for (i = 0; i < nwords; i++) {
1541 			/* check if this word of the free inode summary
1542 			 * map describes an extent with free inodes.
1543 			 */
1544 			if (~inosmap) {
1545 				/* an extent with free inodes has been
1546 				 * found. determine the extent number
1547 				 * and the inode number within the extent.
1548 				 */
1549 				rem = diFindFree(inosmap, 0);
1550 				extno = (sword << L2EXTSPERSUM) + rem;
1551 				rem = diFindFree(le32_to_cpu(iagp->wmap[extno]),
1552 						 0);
1553 				if (rem >= INOSPEREXT) {
1554 					IREAD_UNLOCK(ipimap);
1555 					release_metapage(mp);
1556 					AG_UNLOCK(imap, agno);
1557 					jfs_error(ip->i_sb,
1558 						  "diAlloc: can't find free bit "
1559 						  "in wmap");
1560 					return EIO;
1561 				}
1562 
1563 				/* determine the inode number within the
1564 				 * iag and allocate the inode from the
1565 				 * map.
1566 				 */
1567 				ino = (extno << L2INOSPEREXT) + rem;
1568 				rc = diAllocBit(imap, iagp, ino);
1569 				IREAD_UNLOCK(ipimap);
1570 				if (rc)
1571 					assert(rc == -EIO);
1572 				else {
1573 					/* set the results of the allocation
1574 					 * and write the iag.
1575 					 */
1576 					diInitInode(ip, iagno, ino, extno,
1577 						    iagp);
1578 					mark_metapage_dirty(mp);
1579 				}
1580 				release_metapage(mp);
1581 
1582 				/* free the AG lock and return.
1583 				 */
1584 				AG_UNLOCK(imap, agno);
1585 				return (rc);
1586 
1587 			}
1588 
1589 			/* check if we may allocate an extent of free
1590 			 * inodes and whether this word of the free
1591 			 * extents summary map describes a free extent.
1592 			 */
1593 			if (addext && ~extsmap) {
1594 				/* a free extent has been found.  determine
1595 				 * the extent number.
1596 				 */
1597 				rem = diFindFree(extsmap, 0);
1598 				extno = (sword << L2EXTSPERSUM) + rem;
1599 
1600 				/* allocate an extent of free inodes.
1601 				 */
1602 				if ((rc = diNewExt(imap, iagp, extno))) {
1603 					/* if there is no disk space for a
1604 					 * new extent, try to allocate the
1605 					 * disk inode from somewhere else.
1606 					 */
1607 					if (rc == -ENOSPC)
1608 						break;
1609 
1610 					assert(rc == -EIO);
1611 				} else {
1612 					/* set the results of the allocation
1613 					 * and write the iag.
1614 					 */
1615 					diInitInode(ip, iagno,
1616 						    extno << L2INOSPEREXT,
1617 						    extno, iagp);
1618 					mark_metapage_dirty(mp);
1619 				}
1620 				release_metapage(mp);
1621 				/* free the imap inode & the AG lock & return.
1622 				 */
1623 				IREAD_UNLOCK(ipimap);
1624 				AG_UNLOCK(imap, agno);
1625 				return (rc);
1626 			}
1627 
1628 			/* move on to the next set of summary map words.
1629 			 */
1630 			sword = (sword == SMAPSZ - 1) ? 0 : sword + 1;
1631 			inosmap = le32_to_cpu(iagp->inosmap[sword]);
1632 			extsmap = le32_to_cpu(iagp->extsmap[sword]);
1633 		}
1634 	}
1635 	/* unlock imap inode */
1636 	IREAD_UNLOCK(ipimap);
1637 
1638 	/* nothing doing in this iag, so release it. */
1639 	release_metapage(mp);
1640 
1641       tryag:
1642 	/*
1643 	 * try to allocate anywhere within the same AG as the parent inode.
1644 	 */
1645 	rc = diAllocAG(imap, agno, dir, ip);
1646 
1647 	AG_UNLOCK(imap, agno);
1648 
1649 	if (rc != -ENOSPC)
1650 		return (rc);
1651 
1652 	/*
1653 	 * try to allocate in any AG.
1654 	 */
1655 	return (diAllocAny(imap, agno, dir, ip));
1656 }
1657 
1658 
1659 /*
1660  * NAME:        diAllocAG(imap,agno,dir,ip)
1661  *
1662  * FUNCTION:    allocate a disk inode from the allocation group.
1663  *
1664  *		this routine first determines if a new extent of free
1665  *		inodes should be added for the allocation group, with
1666  *		the current request satisfied from this extent. if this
1667  *		is the case, an attempt will be made to do just that.  if
1668  *		this attempt fails or it has been determined that a new
1669  *		extent should not be added, an attempt is made to satisfy
1670  *		the request by allocating an existing (backed) free inode
1671  *		from the allocation group.
1672  *
1673  * PRE CONDITION: Already have the AG lock for this AG.
1674  *
1675  * PARAMETERS:
1676  *      imap  	- pointer to inode map control structure.
1677  *      agno  	- allocation group to allocate from.
1678  *      dir  	- TRUE if the new disk inode is for a directory.
1679  *      ip  	- pointer to the new inode to be filled in on successful return
1680  *		  with the disk inode number allocated, its extent address
1681  *		  and the start of the ag.
1682  *
1683  * RETURN VALUES:
1684  *      0       - success.
1685  *      -ENOSPC	- insufficient disk resources.
1686  *      -EIO  	- i/o error.
1687  */
1688 static int
1689 diAllocAG(struct inomap * imap, int agno, boolean_t dir, struct inode *ip)
1690 {
1691 	int rc, addext, numfree, numinos;
1692 
1693 	/* get the number of free and the number of backed disk
1694 	 * inodes currently within the ag.
1695 	 */
1696 	numfree = imap->im_agctl[agno].numfree;
1697 	numinos = imap->im_agctl[agno].numinos;
1698 
1699 	if (numfree > numinos) {
1700 		jfs_error(ip->i_sb, "diAllocAG: numfree > numinos");
1701 		return -EIO;
1702 	}
1703 
1704 	/* determine if we should allocate a new extent of free inodes
1705 	 * within the ag: for directory inodes, add a new extent
1706 	 * if there are a small number of free inodes or number of free
1707 	 * inodes is a small percentage of the number of backed inodes.
1708 	 */
1709 	if (dir == TRUE)
1710 		addext = (numfree < 64 ||
1711 			  (numfree < 256
1712 			   && ((numfree * 100) / numinos) <= 20));
1713 	else
1714 		addext = (numfree == 0);
1715 
1716 	/*
1717 	 * try to allocate a new extent of free inodes.
1718 	 */
1719 	if (addext) {
1720 		/* if free space is not avaliable for this new extent, try
1721 		 * below to allocate a free and existing (already backed)
1722 		 * inode from the ag.
1723 		 */
1724 		if ((rc = diAllocExt(imap, agno, ip)) != -ENOSPC)
1725 			return (rc);
1726 	}
1727 
1728 	/*
1729 	 * try to allocate an existing free inode from the ag.
1730 	 */
1731 	return (diAllocIno(imap, agno, ip));
1732 }
1733 
1734 
1735 /*
1736  * NAME:        diAllocAny(imap,agno,dir,iap)
1737  *
1738  * FUNCTION:    allocate a disk inode from any other allocation group.
1739  *
1740  *		this routine is called when an allocation attempt within
1741  *		the primary allocation group has failed. if attempts to
1742  *		allocate an inode from any allocation group other than the
1743  *		specified primary group.
1744  *
1745  * PARAMETERS:
1746  *      imap  	- pointer to inode map control structure.
1747  *      agno  	- primary allocation group (to avoid).
1748  *      dir  	- TRUE if the new disk inode is for a directory.
1749  *      ip  	- pointer to a new inode to be filled in on successful return
1750  *		  with the disk inode number allocated, its extent address
1751  *		  and the start of the ag.
1752  *
1753  * RETURN VALUES:
1754  *      0       - success.
1755  *      -ENOSPC	- insufficient disk resources.
1756  *      -EIO  	- i/o error.
1757  */
1758 static int
1759 diAllocAny(struct inomap * imap, int agno, boolean_t dir, struct inode *ip)
1760 {
1761 	int ag, rc;
1762 	int maxag = JFS_SBI(imap->im_ipimap->i_sb)->bmap->db_maxag;
1763 
1764 
1765 	/* try to allocate from the ags following agno up to
1766 	 * the maximum ag number.
1767 	 */
1768 	for (ag = agno + 1; ag <= maxag; ag++) {
1769 		AG_LOCK(imap, ag);
1770 
1771 		rc = diAllocAG(imap, ag, dir, ip);
1772 
1773 		AG_UNLOCK(imap, ag);
1774 
1775 		if (rc != -ENOSPC)
1776 			return (rc);
1777 	}
1778 
1779 	/* try to allocate from the ags in front of agno.
1780 	 */
1781 	for (ag = 0; ag < agno; ag++) {
1782 		AG_LOCK(imap, ag);
1783 
1784 		rc = diAllocAG(imap, ag, dir, ip);
1785 
1786 		AG_UNLOCK(imap, ag);
1787 
1788 		if (rc != -ENOSPC)
1789 			return (rc);
1790 	}
1791 
1792 	/* no free disk inodes.
1793 	 */
1794 	return -ENOSPC;
1795 }
1796 
1797 
1798 /*
1799  * NAME:        diAllocIno(imap,agno,ip)
1800  *
1801  * FUNCTION:    allocate a disk inode from the allocation group's free
1802  *		inode list, returning an error if this free list is
1803  *		empty (i.e. no iags on the list).
1804  *
1805  *		allocation occurs from the first iag on the list using
1806  *		the iag's free inode summary map to find the leftmost
1807  *		free inode in the iag.
1808  *
1809  * PRE CONDITION: Already have AG lock for this AG.
1810  *
1811  * PARAMETERS:
1812  *      imap  	- pointer to inode map control structure.
1813  *      agno  	- allocation group.
1814  *      ip  	- pointer to new inode to be filled in on successful return
1815  *		  with the disk inode number allocated, its extent address
1816  *		  and the start of the ag.
1817  *
1818  * RETURN VALUES:
1819  *      0       - success.
1820  *      -ENOSPC	- insufficient disk resources.
1821  *      -EIO  	- i/o error.
1822  */
1823 static int diAllocIno(struct inomap * imap, int agno, struct inode *ip)
1824 {
1825 	int iagno, ino, rc, rem, extno, sword;
1826 	struct metapage *mp;
1827 	struct iag *iagp;
1828 
1829 	/* check if there are iags on the ag's free inode list.
1830 	 */
1831 	if ((iagno = imap->im_agctl[agno].inofree) < 0)
1832 		return -ENOSPC;
1833 
1834 	/* obtain read lock on imap inode */
1835 	IREAD_LOCK(imap->im_ipimap);
1836 
1837 	/* read the iag at the head of the list.
1838 	 */
1839 	if ((rc = diIAGRead(imap, iagno, &mp))) {
1840 		IREAD_UNLOCK(imap->im_ipimap);
1841 		return (rc);
1842 	}
1843 	iagp = (struct iag *) mp->data;
1844 
1845 	/* better be free inodes in this iag if it is on the
1846 	 * list.
1847 	 */
1848 	if (!iagp->nfreeinos) {
1849 		IREAD_UNLOCK(imap->im_ipimap);
1850 		release_metapage(mp);
1851 		jfs_error(ip->i_sb,
1852 			  "diAllocIno: nfreeinos = 0, but iag on freelist");
1853 		return -EIO;
1854 	}
1855 
1856 	/* scan the free inode summary map to find an extent
1857 	 * with free inodes.
1858 	 */
1859 	for (sword = 0;; sword++) {
1860 		if (sword >= SMAPSZ) {
1861 			IREAD_UNLOCK(imap->im_ipimap);
1862 			release_metapage(mp);
1863 			jfs_error(ip->i_sb,
1864 				  "diAllocIno: free inode not found in summary map");
1865 			return -EIO;
1866 		}
1867 
1868 		if (~iagp->inosmap[sword])
1869 			break;
1870 	}
1871 
1872 	/* found a extent with free inodes. determine
1873 	 * the extent number.
1874 	 */
1875 	rem = diFindFree(le32_to_cpu(iagp->inosmap[sword]), 0);
1876 	if (rem >= EXTSPERSUM) {
1877 		IREAD_UNLOCK(imap->im_ipimap);
1878 		release_metapage(mp);
1879 		jfs_error(ip->i_sb, "diAllocIno: no free extent found");
1880 		return -EIO;
1881 	}
1882 	extno = (sword << L2EXTSPERSUM) + rem;
1883 
1884 	/* find the first free inode in the extent.
1885 	 */
1886 	rem = diFindFree(le32_to_cpu(iagp->wmap[extno]), 0);
1887 	if (rem >= INOSPEREXT) {
1888 		IREAD_UNLOCK(imap->im_ipimap);
1889 		release_metapage(mp);
1890 		jfs_error(ip->i_sb, "diAllocIno: free inode not found");
1891 		return -EIO;
1892 	}
1893 
1894 	/* compute the inode number within the iag.
1895 	 */
1896 	ino = (extno << L2INOSPEREXT) + rem;
1897 
1898 	/* allocate the inode.
1899 	 */
1900 	rc = diAllocBit(imap, iagp, ino);
1901 	IREAD_UNLOCK(imap->im_ipimap);
1902 	if (rc) {
1903 		release_metapage(mp);
1904 		return (rc);
1905 	}
1906 
1907 	/* set the results of the allocation and write the iag.
1908 	 */
1909 	diInitInode(ip, iagno, ino, extno, iagp);
1910 	write_metapage(mp);
1911 
1912 	return (0);
1913 }
1914 
1915 
1916 /*
1917  * NAME:        diAllocExt(imap,agno,ip)
1918  *
1919  * FUNCTION:   	add a new extent of free inodes to an iag, allocating
1920  *	       	an inode from this extent to satisfy the current allocation
1921  *	       	request.
1922  *
1923  *		this routine first tries to find an existing iag with free
1924  *		extents through the ag free extent list.  if list is not
1925  *		empty, the head of the list will be selected as the home
1926  *		of the new extent of free inodes.  otherwise (the list is
1927  *		empty), a new iag will be allocated for the ag to contain
1928  *		the extent.
1929  *
1930  *		once an iag has been selected, the free extent summary map
1931  *		is used to locate a free extent within the iag and diNewExt()
1932  *		is called to initialize the extent, with initialization
1933  *		including the allocation of the first inode of the extent
1934  *		for the purpose of satisfying this request.
1935  *
1936  * PARAMETERS:
1937  *      imap  	- pointer to inode map control structure.
1938  *      agno  	- allocation group number.
1939  *      ip  	- pointer to new inode to be filled in on successful return
1940  *		  with the disk inode number allocated, its extent address
1941  *		  and the start of the ag.
1942  *
1943  * RETURN VALUES:
1944  *      0       - success.
1945  *      -ENOSPC	- insufficient disk resources.
1946  *      -EIO  	- i/o error.
1947  */
1948 static int diAllocExt(struct inomap * imap, int agno, struct inode *ip)
1949 {
1950 	int rem, iagno, sword, extno, rc;
1951 	struct metapage *mp;
1952 	struct iag *iagp;
1953 
1954 	/* check if the ag has any iags with free extents.  if not,
1955 	 * allocate a new iag for the ag.
1956 	 */
1957 	if ((iagno = imap->im_agctl[agno].extfree) < 0) {
1958 		/* If successful, diNewIAG will obtain the read lock on the
1959 		 * imap inode.
1960 		 */
1961 		if ((rc = diNewIAG(imap, &iagno, agno, &mp))) {
1962 			return (rc);
1963 		}
1964 		iagp = (struct iag *) mp->data;
1965 
1966 		/* set the ag number if this a brand new iag
1967 		 */
1968 		iagp->agstart =
1969 		    cpu_to_le64(AGTOBLK(agno, imap->im_ipimap));
1970 	} else {
1971 		/* read the iag.
1972 		 */
1973 		IREAD_LOCK(imap->im_ipimap);
1974 		if ((rc = diIAGRead(imap, iagno, &mp))) {
1975 			IREAD_UNLOCK(imap->im_ipimap);
1976 			jfs_error(ip->i_sb, "diAllocExt: error reading iag");
1977 			return rc;
1978 		}
1979 		iagp = (struct iag *) mp->data;
1980 	}
1981 
1982 	/* using the free extent summary map, find a free extent.
1983 	 */
1984 	for (sword = 0;; sword++) {
1985 		if (sword >= SMAPSZ) {
1986 			release_metapage(mp);
1987 			IREAD_UNLOCK(imap->im_ipimap);
1988 			jfs_error(ip->i_sb,
1989 				  "diAllocExt: free ext summary map not found");
1990 			return -EIO;
1991 		}
1992 		if (~iagp->extsmap[sword])
1993 			break;
1994 	}
1995 
1996 	/* determine the extent number of the free extent.
1997 	 */
1998 	rem = diFindFree(le32_to_cpu(iagp->extsmap[sword]), 0);
1999 	if (rem >= EXTSPERSUM) {
2000 		release_metapage(mp);
2001 		IREAD_UNLOCK(imap->im_ipimap);
2002 		jfs_error(ip->i_sb, "diAllocExt: free extent not found");
2003 		return -EIO;
2004 	}
2005 	extno = (sword << L2EXTSPERSUM) + rem;
2006 
2007 	/* initialize the new extent.
2008 	 */
2009 	rc = diNewExt(imap, iagp, extno);
2010 	IREAD_UNLOCK(imap->im_ipimap);
2011 	if (rc) {
2012 		/* something bad happened.  if a new iag was allocated,
2013 		 * place it back on the inode map's iag free list, and
2014 		 * clear the ag number information.
2015 		 */
2016 		if (iagp->nfreeexts == cpu_to_le32(EXTSPERIAG)) {
2017 			IAGFREE_LOCK(imap);
2018 			iagp->iagfree = cpu_to_le32(imap->im_freeiag);
2019 			imap->im_freeiag = iagno;
2020 			IAGFREE_UNLOCK(imap);
2021 		}
2022 		write_metapage(mp);
2023 		return (rc);
2024 	}
2025 
2026 	/* set the results of the allocation and write the iag.
2027 	 */
2028 	diInitInode(ip, iagno, extno << L2INOSPEREXT, extno, iagp);
2029 
2030 	write_metapage(mp);
2031 
2032 	return (0);
2033 }
2034 
2035 
2036 /*
2037  * NAME:        diAllocBit(imap,iagp,ino)
2038  *
2039  * FUNCTION:   	allocate a backed inode from an iag.
2040  *
2041  *		this routine performs the mechanics of allocating a
2042  *		specified inode from a backed extent.
2043  *
2044  *		if the inode to be allocated represents the last free
2045  *		inode within the iag, the iag will be removed from the
2046  *		ag free inode list.
2047  *
2048  *		a careful update approach is used to provide consistency
2049  *		in the face of updates to multiple buffers.  under this
2050  *		approach, all required buffers are obtained before making
2051  *		any updates and are held all are updates are complete.
2052  *
2053  * PRE CONDITION: Already have buffer lock on iagp.  Already have AG lock on
2054  *	this AG.  Must have read lock on imap inode.
2055  *
2056  * PARAMETERS:
2057  *      imap  	- pointer to inode map control structure.
2058  *      iagp  	- pointer to iag.
2059  *      ino   	- inode number to be allocated within the iag.
2060  *
2061  * RETURN VALUES:
2062  *      0       - success.
2063  *      -ENOSPC	- insufficient disk resources.
2064  *      -EIO  	- i/o error.
2065  */
2066 static int diAllocBit(struct inomap * imap, struct iag * iagp, int ino)
2067 {
2068 	int extno, bitno, agno, sword, rc;
2069 	struct metapage *amp = NULL, *bmp = NULL;
2070 	struct iag *aiagp = NULL, *biagp = NULL;
2071 	u32 mask;
2072 
2073 	/* check if this is the last free inode within the iag.
2074 	 * if so, it will have to be removed from the ag free
2075 	 * inode list, so get the iags preceeding and following
2076 	 * it on the list.
2077 	 */
2078 	if (iagp->nfreeinos == cpu_to_le32(1)) {
2079 		if ((int) le32_to_cpu(iagp->inofreefwd) >= 0) {
2080 			if ((rc =
2081 			     diIAGRead(imap, le32_to_cpu(iagp->inofreefwd),
2082 				       &amp)))
2083 				return (rc);
2084 			aiagp = (struct iag *) amp->data;
2085 		}
2086 
2087 		if ((int) le32_to_cpu(iagp->inofreeback) >= 0) {
2088 			if ((rc =
2089 			     diIAGRead(imap,
2090 				       le32_to_cpu(iagp->inofreeback),
2091 				       &bmp))) {
2092 				if (amp)
2093 					release_metapage(amp);
2094 				return (rc);
2095 			}
2096 			biagp = (struct iag *) bmp->data;
2097 		}
2098 	}
2099 
2100 	/* get the ag number, extent number, inode number within
2101 	 * the extent.
2102 	 */
2103 	agno = BLKTOAG(le64_to_cpu(iagp->agstart), JFS_SBI(imap->im_ipimap->i_sb));
2104 	extno = ino >> L2INOSPEREXT;
2105 	bitno = ino & (INOSPEREXT - 1);
2106 
2107 	/* compute the mask for setting the map.
2108 	 */
2109 	mask = HIGHORDER >> bitno;
2110 
2111 	/* the inode should be free and backed.
2112 	 */
2113 	if (((le32_to_cpu(iagp->pmap[extno]) & mask) != 0) ||
2114 	    ((le32_to_cpu(iagp->wmap[extno]) & mask) != 0) ||
2115 	    (addressPXD(&iagp->inoext[extno]) == 0)) {
2116 		if (amp)
2117 			release_metapage(amp);
2118 		if (bmp)
2119 			release_metapage(bmp);
2120 
2121 		jfs_error(imap->im_ipimap->i_sb,
2122 			  "diAllocBit: iag inconsistent");
2123 		return -EIO;
2124 	}
2125 
2126 	/* mark the inode as allocated in the working map.
2127 	 */
2128 	iagp->wmap[extno] |= cpu_to_le32(mask);
2129 
2130 	/* check if all inodes within the extent are now
2131 	 * allocated.  if so, update the free inode summary
2132 	 * map to reflect this.
2133 	 */
2134 	if (iagp->wmap[extno] == cpu_to_le32(ONES)) {
2135 		sword = extno >> L2EXTSPERSUM;
2136 		bitno = extno & (EXTSPERSUM - 1);
2137 		iagp->inosmap[sword] |= cpu_to_le32(HIGHORDER >> bitno);
2138 	}
2139 
2140 	/* if this was the last free inode in the iag, remove the
2141 	 * iag from the ag free inode list.
2142 	 */
2143 	if (iagp->nfreeinos == cpu_to_le32(1)) {
2144 		if (amp) {
2145 			aiagp->inofreeback = iagp->inofreeback;
2146 			write_metapage(amp);
2147 		}
2148 
2149 		if (bmp) {
2150 			biagp->inofreefwd = iagp->inofreefwd;
2151 			write_metapage(bmp);
2152 		} else {
2153 			imap->im_agctl[agno].inofree =
2154 			    le32_to_cpu(iagp->inofreefwd);
2155 		}
2156 		iagp->inofreefwd = iagp->inofreeback = cpu_to_le32(-1);
2157 	}
2158 
2159 	/* update the free inode count at the iag, ag, inode
2160 	 * map levels.
2161 	 */
2162 	iagp->nfreeinos = cpu_to_le32(le32_to_cpu(iagp->nfreeinos) - 1);
2163 	imap->im_agctl[agno].numfree -= 1;
2164 	atomic_dec(&imap->im_numfree);
2165 
2166 	return (0);
2167 }
2168 
2169 
2170 /*
2171  * NAME:        diNewExt(imap,iagp,extno)
2172  *
2173  * FUNCTION:    initialize a new extent of inodes for an iag, allocating
2174  *	        the first inode of the extent for use for the current
2175  *	        allocation request.
2176  *
2177  *		disk resources are allocated for the new extent of inodes
2178  *		and the inodes themselves are initialized to reflect their
2179  *		existence within the extent (i.e. their inode numbers and
2180  *		inode extent addresses are set) and their initial state
2181  *		(mode and link count are set to zero).
2182  *
2183  *		if the iag is new, it is not yet on an ag extent free list
2184  *		but will now be placed on this list.
2185  *
2186  *		if the allocation of the new extent causes the iag to
2187  *		have no free extent, the iag will be removed from the
2188  *		ag extent free list.
2189  *
2190  *		if the iag has no free backed inodes, it will be placed
2191  *		on the ag free inode list, since the addition of the new
2192  *		extent will now cause it to have free inodes.
2193  *
2194  *		a careful update approach is used to provide consistency
2195  *		(i.e. list consistency) in the face of updates to multiple
2196  *		buffers.  under this approach, all required buffers are
2197  *		obtained before making any updates and are held until all
2198  *		updates are complete.
2199  *
2200  * PRE CONDITION: Already have buffer lock on iagp.  Already have AG lock on
2201  *	this AG.  Must have read lock on imap inode.
2202  *
2203  * PARAMETERS:
2204  *      imap  	- pointer to inode map control structure.
2205  *      iagp  	- pointer to iag.
2206  *      extno  	- extent number.
2207  *
2208  * RETURN VALUES:
2209  *      0       - success.
2210  *      -ENOSPC	- insufficient disk resources.
2211  *      -EIO  	- i/o error.
2212  */
2213 static int diNewExt(struct inomap * imap, struct iag * iagp, int extno)
2214 {
2215 	int agno, iagno, fwd, back, freei = 0, sword, rc;
2216 	struct iag *aiagp = NULL, *biagp = NULL, *ciagp = NULL;
2217 	struct metapage *amp, *bmp, *cmp, *dmp;
2218 	struct inode *ipimap;
2219 	s64 blkno, hint;
2220 	int i, j;
2221 	u32 mask;
2222 	ino_t ino;
2223 	struct dinode *dp;
2224 	struct jfs_sb_info *sbi;
2225 
2226 	/* better have free extents.
2227 	 */
2228 	if (!iagp->nfreeexts) {
2229 		jfs_error(imap->im_ipimap->i_sb, "diNewExt: no free extents");
2230 		return -EIO;
2231 	}
2232 
2233 	/* get the inode map inode.
2234 	 */
2235 	ipimap = imap->im_ipimap;
2236 	sbi = JFS_SBI(ipimap->i_sb);
2237 
2238 	amp = bmp = cmp = NULL;
2239 
2240 	/* get the ag and iag numbers for this iag.
2241 	 */
2242 	agno = BLKTOAG(le64_to_cpu(iagp->agstart), sbi);
2243 	iagno = le32_to_cpu(iagp->iagnum);
2244 
2245 	/* check if this is the last free extent within the
2246 	 * iag.  if so, the iag must be removed from the ag
2247 	 * free extent list, so get the iags preceeding and
2248 	 * following the iag on this list.
2249 	 */
2250 	if (iagp->nfreeexts == cpu_to_le32(1)) {
2251 		if ((fwd = le32_to_cpu(iagp->extfreefwd)) >= 0) {
2252 			if ((rc = diIAGRead(imap, fwd, &amp)))
2253 				return (rc);
2254 			aiagp = (struct iag *) amp->data;
2255 		}
2256 
2257 		if ((back = le32_to_cpu(iagp->extfreeback)) >= 0) {
2258 			if ((rc = diIAGRead(imap, back, &bmp)))
2259 				goto error_out;
2260 			biagp = (struct iag *) bmp->data;
2261 		}
2262 	} else {
2263 		/* the iag has free extents.  if all extents are free
2264 		 * (as is the case for a newly allocated iag), the iag
2265 		 * must be added to the ag free extent list, so get
2266 		 * the iag at the head of the list in preparation for
2267 		 * adding this iag to this list.
2268 		 */
2269 		fwd = back = -1;
2270 		if (iagp->nfreeexts == cpu_to_le32(EXTSPERIAG)) {
2271 			if ((fwd = imap->im_agctl[agno].extfree) >= 0) {
2272 				if ((rc = diIAGRead(imap, fwd, &amp)))
2273 					goto error_out;
2274 				aiagp = (struct iag *) amp->data;
2275 			}
2276 		}
2277 	}
2278 
2279 	/* check if the iag has no free inodes.  if so, the iag
2280 	 * will have to be added to the ag free inode list, so get
2281 	 * the iag at the head of the list in preparation for
2282 	 * adding this iag to this list.  in doing this, we must
2283 	 * check if we already have the iag at the head of
2284 	 * the list in hand.
2285 	 */
2286 	if (iagp->nfreeinos == 0) {
2287 		freei = imap->im_agctl[agno].inofree;
2288 
2289 		if (freei >= 0) {
2290 			if (freei == fwd) {
2291 				ciagp = aiagp;
2292 			} else if (freei == back) {
2293 				ciagp = biagp;
2294 			} else {
2295 				if ((rc = diIAGRead(imap, freei, &cmp)))
2296 					goto error_out;
2297 				ciagp = (struct iag *) cmp->data;
2298 			}
2299 			if (ciagp == NULL) {
2300 				jfs_error(imap->im_ipimap->i_sb,
2301 					  "diNewExt: ciagp == NULL");
2302 				rc = -EIO;
2303 				goto error_out;
2304 			}
2305 		}
2306 	}
2307 
2308 	/* allocate disk space for the inode extent.
2309 	 */
2310 	if ((extno == 0) || (addressPXD(&iagp->inoext[extno - 1]) == 0))
2311 		hint = ((s64) agno << sbi->bmap->db_agl2size) - 1;
2312 	else
2313 		hint = addressPXD(&iagp->inoext[extno - 1]) +
2314 		    lengthPXD(&iagp->inoext[extno - 1]) - 1;
2315 
2316 	if ((rc = dbAlloc(ipimap, hint, (s64) imap->im_nbperiext, &blkno)))
2317 		goto error_out;
2318 
2319 	/* compute the inode number of the first inode within the
2320 	 * extent.
2321 	 */
2322 	ino = (iagno << L2INOSPERIAG) + (extno << L2INOSPEREXT);
2323 
2324 	/* initialize the inodes within the newly allocated extent a
2325 	 * page at a time.
2326 	 */
2327 	for (i = 0; i < imap->im_nbperiext; i += sbi->nbperpage) {
2328 		/* get a buffer for this page of disk inodes.
2329 		 */
2330 		dmp = get_metapage(ipimap, blkno + i, PSIZE, 1);
2331 		if (dmp == NULL) {
2332 			rc = -EIO;
2333 			goto error_out;
2334 		}
2335 		dp = (struct dinode *) dmp->data;
2336 
2337 		/* initialize the inode number, mode, link count and
2338 		 * inode extent address.
2339 		 */
2340 		for (j = 0; j < INOSPERPAGE; j++, dp++, ino++) {
2341 			dp->di_inostamp = cpu_to_le32(sbi->inostamp);
2342 			dp->di_number = cpu_to_le32(ino);
2343 			dp->di_fileset = cpu_to_le32(FILESYSTEM_I);
2344 			dp->di_mode = 0;
2345 			dp->di_nlink = 0;
2346 			PXDaddress(&(dp->di_ixpxd), blkno);
2347 			PXDlength(&(dp->di_ixpxd), imap->im_nbperiext);
2348 		}
2349 		write_metapage(dmp);
2350 	}
2351 
2352 	/* if this is the last free extent within the iag, remove the
2353 	 * iag from the ag free extent list.
2354 	 */
2355 	if (iagp->nfreeexts == cpu_to_le32(1)) {
2356 		if (fwd >= 0)
2357 			aiagp->extfreeback = iagp->extfreeback;
2358 
2359 		if (back >= 0)
2360 			biagp->extfreefwd = iagp->extfreefwd;
2361 		else
2362 			imap->im_agctl[agno].extfree =
2363 			    le32_to_cpu(iagp->extfreefwd);
2364 
2365 		iagp->extfreefwd = iagp->extfreeback = cpu_to_le32(-1);
2366 	} else {
2367 		/* if the iag has all free extents (newly allocated iag),
2368 		 * add the iag to the ag free extent list.
2369 		 */
2370 		if (iagp->nfreeexts == cpu_to_le32(EXTSPERIAG)) {
2371 			if (fwd >= 0)
2372 				aiagp->extfreeback = cpu_to_le32(iagno);
2373 
2374 			iagp->extfreefwd = cpu_to_le32(fwd);
2375 			iagp->extfreeback = cpu_to_le32(-1);
2376 			imap->im_agctl[agno].extfree = iagno;
2377 		}
2378 	}
2379 
2380 	/* if the iag has no free inodes, add the iag to the
2381 	 * ag free inode list.
2382 	 */
2383 	if (iagp->nfreeinos == 0) {
2384 		if (freei >= 0)
2385 			ciagp->inofreeback = cpu_to_le32(iagno);
2386 
2387 		iagp->inofreefwd =
2388 		    cpu_to_le32(imap->im_agctl[agno].inofree);
2389 		iagp->inofreeback = cpu_to_le32(-1);
2390 		imap->im_agctl[agno].inofree = iagno;
2391 	}
2392 
2393 	/* initialize the extent descriptor of the extent. */
2394 	PXDlength(&iagp->inoext[extno], imap->im_nbperiext);
2395 	PXDaddress(&iagp->inoext[extno], blkno);
2396 
2397 	/* initialize the working and persistent map of the extent.
2398 	 * the working map will be initialized such that
2399 	 * it indicates the first inode of the extent is allocated.
2400 	 */
2401 	iagp->wmap[extno] = cpu_to_le32(HIGHORDER);
2402 	iagp->pmap[extno] = 0;
2403 
2404 	/* update the free inode and free extent summary maps
2405 	 * for the extent to indicate the extent has free inodes
2406 	 * and no longer represents a free extent.
2407 	 */
2408 	sword = extno >> L2EXTSPERSUM;
2409 	mask = HIGHORDER >> (extno & (EXTSPERSUM - 1));
2410 	iagp->extsmap[sword] |= cpu_to_le32(mask);
2411 	iagp->inosmap[sword] &= cpu_to_le32(~mask);
2412 
2413 	/* update the free inode and free extent counts for the
2414 	 * iag.
2415 	 */
2416 	iagp->nfreeinos = cpu_to_le32(le32_to_cpu(iagp->nfreeinos) +
2417 				      (INOSPEREXT - 1));
2418 	iagp->nfreeexts = cpu_to_le32(le32_to_cpu(iagp->nfreeexts) - 1);
2419 
2420 	/* update the free and backed inode counts for the ag.
2421 	 */
2422 	imap->im_agctl[agno].numfree += (INOSPEREXT - 1);
2423 	imap->im_agctl[agno].numinos += INOSPEREXT;
2424 
2425 	/* update the free and backed inode counts for the inode map.
2426 	 */
2427 	atomic_add(INOSPEREXT - 1, &imap->im_numfree);
2428 	atomic_add(INOSPEREXT, &imap->im_numinos);
2429 
2430 	/* write the iags.
2431 	 */
2432 	if (amp)
2433 		write_metapage(amp);
2434 	if (bmp)
2435 		write_metapage(bmp);
2436 	if (cmp)
2437 		write_metapage(cmp);
2438 
2439 	return (0);
2440 
2441       error_out:
2442 
2443 	/* release the iags.
2444 	 */
2445 	if (amp)
2446 		release_metapage(amp);
2447 	if (bmp)
2448 		release_metapage(bmp);
2449 	if (cmp)
2450 		release_metapage(cmp);
2451 
2452 	return (rc);
2453 }
2454 
2455 
2456 /*
2457  * NAME:        diNewIAG(imap,iagnop,agno)
2458  *
2459  * FUNCTION:   	allocate a new iag for an allocation group.
2460  *
2461  *		first tries to allocate the iag from the inode map
2462  *		iagfree list:
2463  *		if the list has free iags, the head of the list is removed
2464  *		and returned to satisfy the request.
2465  *		if the inode map's iag free list is empty, the inode map
2466  *		is extended to hold a new iag. this new iag is initialized
2467  *		and returned to satisfy the request.
2468  *
2469  * PARAMETERS:
2470  *      imap  	- pointer to inode map control structure.
2471  *      iagnop 	- pointer to an iag number set with the number of the
2472  *		  newly allocated iag upon successful return.
2473  *      agno  	- allocation group number.
2474  *	bpp	- Buffer pointer to be filled in with new IAG's buffer
2475  *
2476  * RETURN VALUES:
2477  *      0       - success.
2478  *      -ENOSPC	- insufficient disk resources.
2479  *      -EIO  	- i/o error.
2480  *
2481  * serialization:
2482  *	AG lock held on entry/exit;
2483  *	write lock on the map is held inside;
2484  *	read lock on the map is held on successful completion;
2485  *
2486  * note: new iag transaction:
2487  * . synchronously write iag;
2488  * . write log of xtree and inode  of imap;
2489  * . commit;
2490  * . synchronous write of xtree (right to left, bottom to top);
2491  * . at start of logredo(): init in-memory imap with one additional iag page;
2492  * . at end of logredo(): re-read imap inode to determine
2493  *   new imap size;
2494  */
2495 static int
2496 diNewIAG(struct inomap * imap, int *iagnop, int agno, struct metapage ** mpp)
2497 {
2498 	int rc;
2499 	int iagno, i, xlen;
2500 	struct inode *ipimap;
2501 	struct super_block *sb;
2502 	struct jfs_sb_info *sbi;
2503 	struct metapage *mp;
2504 	struct iag *iagp;
2505 	s64 xaddr = 0;
2506 	s64 blkno;
2507 	tid_t tid;
2508 #ifdef _STILL_TO_PORT
2509 	xad_t xad;
2510 #endif				/*  _STILL_TO_PORT */
2511 	struct inode *iplist[1];
2512 
2513 	/* pick up pointers to the inode map and mount inodes */
2514 	ipimap = imap->im_ipimap;
2515 	sb = ipimap->i_sb;
2516 	sbi = JFS_SBI(sb);
2517 
2518 	/* acquire the free iag lock */
2519 	IAGFREE_LOCK(imap);
2520 
2521 	/* if there are any iags on the inode map free iag list,
2522 	 * allocate the iag from the head of the list.
2523 	 */
2524 	if (imap->im_freeiag >= 0) {
2525 		/* pick up the iag number at the head of the list */
2526 		iagno = imap->im_freeiag;
2527 
2528 		/* determine the logical block number of the iag */
2529 		blkno = IAGTOLBLK(iagno, sbi->l2nbperpage);
2530 	} else {
2531 		/* no free iags. the inode map will have to be extented
2532 		 * to include a new iag.
2533 		 */
2534 
2535 		/* acquire inode map lock */
2536 		IWRITE_LOCK(ipimap);
2537 
2538 		if (ipimap->i_size >> L2PSIZE != imap->im_nextiag + 1) {
2539 			IWRITE_UNLOCK(ipimap);
2540 			IAGFREE_UNLOCK(imap);
2541 			jfs_error(imap->im_ipimap->i_sb,
2542 				  "diNewIAG: ipimap->i_size is wrong");
2543 			return -EIO;
2544 		}
2545 
2546 
2547 		/* get the next avaliable iag number */
2548 		iagno = imap->im_nextiag;
2549 
2550 		/* make sure that we have not exceeded the maximum inode
2551 		 * number limit.
2552 		 */
2553 		if (iagno > (MAXIAGS - 1)) {
2554 			/* release the inode map lock */
2555 			IWRITE_UNLOCK(ipimap);
2556 
2557 			rc = -ENOSPC;
2558 			goto out;
2559 		}
2560 
2561 		/*
2562 		 * synchronously append new iag page.
2563 		 */
2564 		/* determine the logical address of iag page to append */
2565 		blkno = IAGTOLBLK(iagno, sbi->l2nbperpage);
2566 
2567 		/* Allocate extent for new iag page */
2568 		xlen = sbi->nbperpage;
2569 		if ((rc = dbAlloc(ipimap, 0, (s64) xlen, &xaddr))) {
2570 			/* release the inode map lock */
2571 			IWRITE_UNLOCK(ipimap);
2572 
2573 			goto out;
2574 		}
2575 
2576 		/* assign a buffer for the page */
2577 		mp = get_metapage(ipimap, xaddr, PSIZE, 1);
2578 		if (!mp) {
2579 			/* Free the blocks allocated for the iag since it was
2580 			 * not successfully added to the inode map
2581 			 */
2582 			dbFree(ipimap, xaddr, (s64) xlen);
2583 
2584 			/* release the inode map lock */
2585 			IWRITE_UNLOCK(ipimap);
2586 
2587 			rc = -EIO;
2588 			goto out;
2589 		}
2590 		iagp = (struct iag *) mp->data;
2591 
2592 		/* init the iag */
2593 		memset(iagp, 0, sizeof(struct iag));
2594 		iagp->iagnum = cpu_to_le32(iagno);
2595 		iagp->inofreefwd = iagp->inofreeback = cpu_to_le32(-1);
2596 		iagp->extfreefwd = iagp->extfreeback = cpu_to_le32(-1);
2597 		iagp->iagfree = cpu_to_le32(-1);
2598 		iagp->nfreeinos = 0;
2599 		iagp->nfreeexts = cpu_to_le32(EXTSPERIAG);
2600 
2601 		/* initialize the free inode summary map (free extent
2602 		 * summary map initialization handled by bzero).
2603 		 */
2604 		for (i = 0; i < SMAPSZ; i++)
2605 			iagp->inosmap[i] = cpu_to_le32(ONES);
2606 
2607 		/*
2608 		 * Invalidate the page after writing and syncing it.
2609 		 * After it's initialized, we access it in a different
2610 		 * address space
2611 		 */
2612 		set_bit(META_discard, &mp->flag);
2613 		flush_metapage(mp);
2614 
2615 		/*
2616 		 * start tyransaction of update of the inode map
2617 		 * addressing structure pointing to the new iag page;
2618 		 */
2619 		tid = txBegin(sb, COMMIT_FORCE);
2620 		down(&JFS_IP(ipimap)->commit_sem);
2621 
2622 		/* update the inode map addressing structure to point to it */
2623 		if ((rc =
2624 		     xtInsert(tid, ipimap, 0, blkno, xlen, &xaddr, 0))) {
2625 			txEnd(tid);
2626 			up(&JFS_IP(ipimap)->commit_sem);
2627 			/* Free the blocks allocated for the iag since it was
2628 			 * not successfully added to the inode map
2629 			 */
2630 			dbFree(ipimap, xaddr, (s64) xlen);
2631 
2632 			/* release the inode map lock */
2633 			IWRITE_UNLOCK(ipimap);
2634 
2635 			goto out;
2636 		}
2637 
2638 		/* update the inode map's inode to reflect the extension */
2639 		ipimap->i_size += PSIZE;
2640 		inode_add_bytes(ipimap, PSIZE);
2641 
2642 		/*
2643 		 * txCommit(COMMIT_FORCE) will synchronously write address
2644 		 * index pages and inode after commit in careful update order
2645 		 * of address index pages (right to left, bottom up);
2646 		 */
2647 		iplist[0] = ipimap;
2648 		rc = txCommit(tid, 1, &iplist[0], COMMIT_FORCE);
2649 
2650 		txEnd(tid);
2651 		up(&JFS_IP(ipimap)->commit_sem);
2652 
2653 		duplicateIXtree(sb, blkno, xlen, &xaddr);
2654 
2655 		/* update the next avaliable iag number */
2656 		imap->im_nextiag += 1;
2657 
2658 		/* Add the iag to the iag free list so we don't lose the iag
2659 		 * if a failure happens now.
2660 		 */
2661 		imap->im_freeiag = iagno;
2662 
2663 		/* Until we have logredo working, we want the imap inode &
2664 		 * control page to be up to date.
2665 		 */
2666 		diSync(ipimap);
2667 
2668 		/* release the inode map lock */
2669 		IWRITE_UNLOCK(ipimap);
2670 	}
2671 
2672 	/* obtain read lock on map */
2673 	IREAD_LOCK(ipimap);
2674 
2675 	/* read the iag */
2676 	if ((rc = diIAGRead(imap, iagno, &mp))) {
2677 		IREAD_UNLOCK(ipimap);
2678 		rc = -EIO;
2679 		goto out;
2680 	}
2681 	iagp = (struct iag *) mp->data;
2682 
2683 	/* remove the iag from the iag free list */
2684 	imap->im_freeiag = le32_to_cpu(iagp->iagfree);
2685 	iagp->iagfree = cpu_to_le32(-1);
2686 
2687 	/* set the return iag number and buffer pointer */
2688 	*iagnop = iagno;
2689 	*mpp = mp;
2690 
2691       out:
2692 	/* release the iag free lock */
2693 	IAGFREE_UNLOCK(imap);
2694 
2695 	return (rc);
2696 }
2697 
2698 /*
2699  * NAME:        diIAGRead()
2700  *
2701  * FUNCTION:    get the buffer for the specified iag within a fileset
2702  *		or aggregate inode map.
2703  *
2704  * PARAMETERS:
2705  *      imap  	- pointer to inode map control structure.
2706  *      iagno  	- iag number.
2707  *      bpp  	- point to buffer pointer to be filled in on successful
2708  *		  exit.
2709  *
2710  * SERIALIZATION:
2711  *	must have read lock on imap inode
2712  *	(When called by diExtendFS, the filesystem is quiesced, therefore
2713  *	 the read lock is unnecessary.)
2714  *
2715  * RETURN VALUES:
2716  *      0       - success.
2717  *      -EIO  	- i/o error.
2718  */
2719 static int diIAGRead(struct inomap * imap, int iagno, struct metapage ** mpp)
2720 {
2721 	struct inode *ipimap = imap->im_ipimap;
2722 	s64 blkno;
2723 
2724 	/* compute the logical block number of the iag. */
2725 	blkno = IAGTOLBLK(iagno, JFS_SBI(ipimap->i_sb)->l2nbperpage);
2726 
2727 	/* read the iag. */
2728 	*mpp = read_metapage(ipimap, blkno, PSIZE, 0);
2729 	if (*mpp == NULL) {
2730 		return -EIO;
2731 	}
2732 
2733 	return (0);
2734 }
2735 
2736 /*
2737  * NAME:        diFindFree()
2738  *
2739  * FUNCTION:    find the first free bit in a word starting at
2740  *		the specified bit position.
2741  *
2742  * PARAMETERS:
2743  *      word  	- word to be examined.
2744  *      start  	- starting bit position.
2745  *
2746  * RETURN VALUES:
2747  *      bit position of first free bit in the word or 32 if
2748  *	no free bits were found.
2749  */
2750 static int diFindFree(u32 word, int start)
2751 {
2752 	int bitno;
2753 	assert(start < 32);
2754 	/* scan the word for the first free bit. */
2755 	for (word <<= start, bitno = start; bitno < 32;
2756 	     bitno++, word <<= 1) {
2757 		if ((word & HIGHORDER) == 0)
2758 			break;
2759 	}
2760 	return (bitno);
2761 }
2762 
2763 /*
2764  * NAME:	diUpdatePMap()
2765  *
2766  * FUNCTION: Update the persistent map in an IAG for the allocation or
2767  *	freeing of the specified inode.
2768  *
2769  * PRE CONDITIONS: Working map has already been updated for allocate.
2770  *
2771  * PARAMETERS:
2772  *	ipimap	- Incore inode map inode
2773  *	inum	- Number of inode to mark in permanent map
2774  *	is_free	- If TRUE indicates inode should be marked freed, otherwise
2775  *		  indicates inode should be marked allocated.
2776  *
2777  * RETURN VALUES:
2778  *		0 for success
2779  */
2780 int
2781 diUpdatePMap(struct inode *ipimap,
2782 	     unsigned long inum, boolean_t is_free, struct tblock * tblk)
2783 {
2784 	int rc;
2785 	struct iag *iagp;
2786 	struct metapage *mp;
2787 	int iagno, ino, extno, bitno;
2788 	struct inomap *imap;
2789 	u32 mask;
2790 	struct jfs_log *log;
2791 	int lsn, difft, diffp;
2792 
2793 	imap = JFS_IP(ipimap)->i_imap;
2794 	/* get the iag number containing the inode */
2795 	iagno = INOTOIAG(inum);
2796 	/* make sure that the iag is contained within the map */
2797 	if (iagno >= imap->im_nextiag) {
2798 		jfs_error(ipimap->i_sb,
2799 			  "diUpdatePMap: the iag is outside the map");
2800 		return -EIO;
2801 	}
2802 	/* read the iag */
2803 	IREAD_LOCK(ipimap);
2804 	rc = diIAGRead(imap, iagno, &mp);
2805 	IREAD_UNLOCK(ipimap);
2806 	if (rc)
2807 		return (rc);
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 		if (difft < diffp) {
2872 			mp->lsn = lsn;
2873 			/* move mp after tblock in logsync list */
2874 			LOGSYNC_LOCK(log);
2875 			list_move(&mp->synclist, &tblk->synclist);
2876 			LOGSYNC_UNLOCK(log);
2877 		}
2878 		/* inherit younger/larger clsn */
2879 		LOGSYNC_LOCK(log);
2880 		assert(mp->clsn);
2881 		logdiff(difft, tblk->clsn, log);
2882 		logdiff(diffp, mp->clsn, log);
2883 		if (difft > diffp)
2884 			mp->clsn = tblk->clsn;
2885 		LOGSYNC_UNLOCK(log);
2886 	} else {
2887 		mp->log = log;
2888 		mp->lsn = lsn;
2889 		/* insert mp after tblock in logsync list */
2890 		LOGSYNC_LOCK(log);
2891 		log->count++;
2892 		list_add(&mp->synclist, &tblk->synclist);
2893 		mp->clsn = tblk->clsn;
2894 		LOGSYNC_UNLOCK(log);
2895 	}
2896 	write_metapage(mp);
2897 	return (0);
2898 }
2899 
2900 /*
2901  *	diExtendFS()
2902  *
2903  * function: update imap for extendfs();
2904  *
2905  * note: AG size has been increased s.t. each k old contiguous AGs are
2906  * coalesced into a new AG;
2907  */
2908 int diExtendFS(struct inode *ipimap, struct inode *ipbmap)
2909 {
2910 	int rc, rcx = 0;
2911 	struct inomap *imap = JFS_IP(ipimap)->i_imap;
2912 	struct iag *iagp = NULL, *hiagp = NULL;
2913 	struct bmap *mp = JFS_SBI(ipbmap->i_sb)->bmap;
2914 	struct metapage *bp, *hbp;
2915 	int i, n, head;
2916 	int numinos, xnuminos = 0, xnumfree = 0;
2917 	s64 agstart;
2918 
2919 	jfs_info("diExtendFS: nextiag:%d numinos:%d numfree:%d",
2920 		   imap->im_nextiag, atomic_read(&imap->im_numinos),
2921 		   atomic_read(&imap->im_numfree));
2922 
2923 	/*
2924 	 *      reconstruct imap
2925 	 *
2926 	 * coalesce contiguous k (newAGSize/oldAGSize) AGs;
2927 	 * i.e., (AGi, ..., AGj) where i = k*n and j = k*(n+1) - 1 to AGn;
2928 	 * note: new AG size = old AG size * (2**x).
2929 	 */
2930 
2931 	/* init per AG control information im_agctl[] */
2932 	for (i = 0; i < MAXAG; i++) {
2933 		imap->im_agctl[i].inofree = -1;
2934 		imap->im_agctl[i].extfree = -1;
2935 		imap->im_agctl[i].numinos = 0;	/* number of backed inodes */
2936 		imap->im_agctl[i].numfree = 0;	/* number of free backed inodes */
2937 	}
2938 
2939 	/*
2940 	 *      process each iag page of the map.
2941 	 *
2942 	 * rebuild AG Free Inode List, AG Free Inode Extent List;
2943 	 */
2944 	for (i = 0; i < imap->im_nextiag; i++) {
2945 		if ((rc = diIAGRead(imap, i, &bp))) {
2946 			rcx = rc;
2947 			continue;
2948 		}
2949 		iagp = (struct iag *) bp->data;
2950 		if (le32_to_cpu(iagp->iagnum) != i) {
2951 			release_metapage(bp);
2952 			jfs_error(ipimap->i_sb,
2953 				  "diExtendFs: unexpected value of iagnum");
2954 			return -EIO;
2955 		}
2956 
2957 		/* leave free iag in the free iag list */
2958 		if (iagp->nfreeexts == cpu_to_le32(EXTSPERIAG)) {
2959 		        release_metapage(bp);
2960 			continue;
2961 		}
2962 
2963 		/* agstart that computes to the same ag is treated as same; */
2964 		agstart = le64_to_cpu(iagp->agstart);
2965 		/* iagp->agstart = agstart & ~(mp->db_agsize - 1); */
2966 		n = agstart >> mp->db_agl2size;
2967 
2968 		/* compute backed inodes */
2969 		numinos = (EXTSPERIAG - le32_to_cpu(iagp->nfreeexts))
2970 		    << L2INOSPEREXT;
2971 		if (numinos > 0) {
2972 			/* merge AG backed inodes */
2973 			imap->im_agctl[n].numinos += numinos;
2974 			xnuminos += numinos;
2975 		}
2976 
2977 		/* if any backed free inodes, insert at AG free inode list */
2978 		if ((int) le32_to_cpu(iagp->nfreeinos) > 0) {
2979 			if ((head = imap->im_agctl[n].inofree) == -1) {
2980 				iagp->inofreefwd = cpu_to_le32(-1);
2981 				iagp->inofreeback = cpu_to_le32(-1);
2982 			} else {
2983 				if ((rc = diIAGRead(imap, head, &hbp))) {
2984 					rcx = rc;
2985 					goto nextiag;
2986 				}
2987 				hiagp = (struct iag *) hbp->data;
2988 				hiagp->inofreeback = iagp->iagnum;
2989 				iagp->inofreefwd = cpu_to_le32(head);
2990 				iagp->inofreeback = cpu_to_le32(-1);
2991 				write_metapage(hbp);
2992 			}
2993 
2994 			imap->im_agctl[n].inofree =
2995 			    le32_to_cpu(iagp->iagnum);
2996 
2997 			/* merge AG backed free inodes */
2998 			imap->im_agctl[n].numfree +=
2999 			    le32_to_cpu(iagp->nfreeinos);
3000 			xnumfree += le32_to_cpu(iagp->nfreeinos);
3001 		}
3002 
3003 		/* if any free extents, insert at AG free extent list */
3004 		if (le32_to_cpu(iagp->nfreeexts) > 0) {
3005 			if ((head = imap->im_agctl[n].extfree) == -1) {
3006 				iagp->extfreefwd = cpu_to_le32(-1);
3007 				iagp->extfreeback = cpu_to_le32(-1);
3008 			} else {
3009 				if ((rc = diIAGRead(imap, head, &hbp))) {
3010 					rcx = rc;
3011 					goto nextiag;
3012 				}
3013 				hiagp = (struct iag *) hbp->data;
3014 				hiagp->extfreeback = iagp->iagnum;
3015 				iagp->extfreefwd = cpu_to_le32(head);
3016 				iagp->extfreeback = cpu_to_le32(-1);
3017 				write_metapage(hbp);
3018 			}
3019 
3020 			imap->im_agctl[n].extfree =
3021 			    le32_to_cpu(iagp->iagnum);
3022 		}
3023 
3024 	      nextiag:
3025 		write_metapage(bp);
3026 	}
3027 
3028 	if (xnuminos != atomic_read(&imap->im_numinos) ||
3029 	    xnumfree != atomic_read(&imap->im_numfree)) {
3030 		jfs_error(ipimap->i_sb,
3031 			  "diExtendFs: numinos or numfree incorrect");
3032 		return -EIO;
3033 	}
3034 
3035 	return rcx;
3036 }
3037 
3038 
3039 /*
3040  *	duplicateIXtree()
3041  *
3042  * serialization: IWRITE_LOCK held on entry/exit
3043  *
3044  * note: shadow page with regular inode (rel.2);
3045  */
3046 static void duplicateIXtree(struct super_block *sb, s64 blkno,
3047 			    int xlen, s64 *xaddr)
3048 {
3049 	struct jfs_superblock *j_sb;
3050 	struct buffer_head *bh;
3051 	struct inode *ip;
3052 	tid_t tid;
3053 
3054 	/* if AIT2 ipmap2 is bad, do not try to update it */
3055 	if (JFS_SBI(sb)->mntflag & JFS_BAD_SAIT)	/* s_flag */
3056 		return;
3057 	ip = diReadSpecial(sb, FILESYSTEM_I, 1);
3058 	if (ip == NULL) {
3059 		JFS_SBI(sb)->mntflag |= JFS_BAD_SAIT;
3060 		if (readSuper(sb, &bh))
3061 			return;
3062 		j_sb = (struct jfs_superblock *)bh->b_data;
3063 		j_sb->s_flag |= cpu_to_le32(JFS_BAD_SAIT);
3064 
3065 		mark_buffer_dirty(bh);
3066 		sync_dirty_buffer(bh);
3067 		brelse(bh);
3068 		return;
3069 	}
3070 
3071 	/* start transaction */
3072 	tid = txBegin(sb, COMMIT_FORCE);
3073 	/* update the inode map addressing structure to point to it */
3074 	if (xtInsert(tid, ip, 0, blkno, xlen, xaddr, 0)) {
3075 		JFS_SBI(sb)->mntflag |= JFS_BAD_SAIT;
3076 		txAbort(tid, 1);
3077 		goto cleanup;
3078 
3079 	}
3080 	/* update the inode map's inode to reflect the extension */
3081 	ip->i_size += PSIZE;
3082 	inode_add_bytes(ip, PSIZE);
3083 	txCommit(tid, 1, &ip, COMMIT_FORCE);
3084       cleanup:
3085 	txEnd(tid);
3086 	diFreeSpecial(ip);
3087 }
3088 
3089 /*
3090  * NAME:        copy_from_dinode()
3091  *
3092  * FUNCTION:    Copies inode info from disk inode to in-memory inode
3093  *
3094  * RETURN VALUES:
3095  *      0       - success
3096  *      -ENOMEM	- insufficient memory
3097  */
3098 static int copy_from_dinode(struct dinode * dip, struct inode *ip)
3099 {
3100 	struct jfs_inode_info *jfs_ip = JFS_IP(ip);
3101 
3102 	jfs_ip->fileset = le32_to_cpu(dip->di_fileset);
3103 	jfs_ip->mode2 = le32_to_cpu(dip->di_mode);
3104 
3105 	ip->i_mode = le32_to_cpu(dip->di_mode) & 0xffff;
3106 	ip->i_nlink = le32_to_cpu(dip->di_nlink);
3107 	ip->i_uid = le32_to_cpu(dip->di_uid);
3108 	ip->i_gid = le32_to_cpu(dip->di_gid);
3109 	ip->i_size = le64_to_cpu(dip->di_size);
3110 	ip->i_atime.tv_sec = le32_to_cpu(dip->di_atime.tv_sec);
3111 	ip->i_atime.tv_nsec = le32_to_cpu(dip->di_atime.tv_nsec);
3112 	ip->i_mtime.tv_sec = le32_to_cpu(dip->di_mtime.tv_sec);
3113 	ip->i_mtime.tv_nsec = le32_to_cpu(dip->di_mtime.tv_nsec);
3114 	ip->i_ctime.tv_sec = le32_to_cpu(dip->di_ctime.tv_sec);
3115 	ip->i_ctime.tv_nsec = le32_to_cpu(dip->di_ctime.tv_nsec);
3116 	ip->i_blksize = ip->i_sb->s_blocksize;
3117 	ip->i_blocks = LBLK2PBLK(ip->i_sb, le64_to_cpu(dip->di_nblocks));
3118 	ip->i_generation = le32_to_cpu(dip->di_gen);
3119 
3120 	jfs_ip->ixpxd = dip->di_ixpxd;	/* in-memory pxd's are little-endian */
3121 	jfs_ip->acl = dip->di_acl;	/* as are dxd's */
3122 	jfs_ip->ea = dip->di_ea;
3123 	jfs_ip->next_index = le32_to_cpu(dip->di_next_index);
3124 	jfs_ip->otime = le32_to_cpu(dip->di_otime.tv_sec);
3125 	jfs_ip->acltype = le32_to_cpu(dip->di_acltype);
3126 
3127 	if (S_ISCHR(ip->i_mode) || S_ISBLK(ip->i_mode)) {
3128 		jfs_ip->dev = le32_to_cpu(dip->di_rdev);
3129 		ip->i_rdev = new_decode_dev(jfs_ip->dev);
3130 	}
3131 
3132 	if (S_ISDIR(ip->i_mode)) {
3133 		memcpy(&jfs_ip->i_dirtable, &dip->di_dirtable, 384);
3134 	} else if (S_ISREG(ip->i_mode) || S_ISLNK(ip->i_mode)) {
3135 		memcpy(&jfs_ip->i_xtroot, &dip->di_xtroot, 288);
3136 	} else
3137 		memcpy(&jfs_ip->i_inline_ea, &dip->di_inlineea, 128);
3138 
3139 	/* Zero the in-memory-only stuff */
3140 	jfs_ip->cflag = 0;
3141 	jfs_ip->btindex = 0;
3142 	jfs_ip->btorder = 0;
3143 	jfs_ip->bxflag = 0;
3144 	jfs_ip->blid = 0;
3145 	jfs_ip->atlhead = 0;
3146 	jfs_ip->atltail = 0;
3147 	jfs_ip->xtlid = 0;
3148 	return (0);
3149 }
3150 
3151 /*
3152  * NAME:        copy_to_dinode()
3153  *
3154  * FUNCTION:    Copies inode info from in-memory inode to disk inode
3155  */
3156 static void copy_to_dinode(struct dinode * dip, struct inode *ip)
3157 {
3158 	struct jfs_inode_info *jfs_ip = JFS_IP(ip);
3159 
3160 	dip->di_fileset = cpu_to_le32(jfs_ip->fileset);
3161 	dip->di_inostamp = cpu_to_le32(JFS_SBI(ip->i_sb)->inostamp);
3162 	dip->di_number = cpu_to_le32(ip->i_ino);
3163 	dip->di_gen = cpu_to_le32(ip->i_generation);
3164 	dip->di_size = cpu_to_le64(ip->i_size);
3165 	dip->di_nblocks = cpu_to_le64(PBLK2LBLK(ip->i_sb, ip->i_blocks));
3166 	dip->di_nlink = cpu_to_le32(ip->i_nlink);
3167 	dip->di_uid = cpu_to_le32(ip->i_uid);
3168 	dip->di_gid = cpu_to_le32(ip->i_gid);
3169 	/*
3170 	 * mode2 is only needed for storing the higher order bits.
3171 	 * Trust i_mode for the lower order ones
3172 	 */
3173 	dip->di_mode = cpu_to_le32((jfs_ip->mode2 & 0xffff0000) | ip->i_mode);
3174 	dip->di_atime.tv_sec = cpu_to_le32(ip->i_atime.tv_sec);
3175 	dip->di_atime.tv_nsec = cpu_to_le32(ip->i_atime.tv_nsec);
3176 	dip->di_ctime.tv_sec = cpu_to_le32(ip->i_ctime.tv_sec);
3177 	dip->di_ctime.tv_nsec = cpu_to_le32(ip->i_ctime.tv_nsec);
3178 	dip->di_mtime.tv_sec = cpu_to_le32(ip->i_mtime.tv_sec);
3179 	dip->di_mtime.tv_nsec = cpu_to_le32(ip->i_mtime.tv_nsec);
3180 	dip->di_ixpxd = jfs_ip->ixpxd;	/* in-memory pxd's are little-endian */
3181 	dip->di_acl = jfs_ip->acl;	/* as are dxd's */
3182 	dip->di_ea = jfs_ip->ea;
3183 	dip->di_next_index = cpu_to_le32(jfs_ip->next_index);
3184 	dip->di_otime.tv_sec = cpu_to_le32(jfs_ip->otime);
3185 	dip->di_otime.tv_nsec = 0;
3186 	dip->di_acltype = cpu_to_le32(jfs_ip->acltype);
3187 	if (S_ISCHR(ip->i_mode) || S_ISBLK(ip->i_mode))
3188 		dip->di_rdev = cpu_to_le32(jfs_ip->dev);
3189 }
3190 
3191 #ifdef	_JFS_DEBUG_IMAP
3192 /*
3193  *	DBGdiInit()
3194  */
3195 static void *DBGdiInit(struct inomap * imap)
3196 {
3197 	u32 *dimap;
3198 	int size;
3199 	size = 64 * 1024;
3200 	if ((dimap = (u32 *) xmalloc(size, L2PSIZE, kernel_heap)) == NULL)
3201 		assert(0);
3202 	bzero((void *) dimap, size);
3203 	imap->im_DBGdimap = dimap;
3204 }
3205 
3206 /*
3207  *	DBGdiAlloc()
3208  */
3209 static void DBGdiAlloc(struct inomap * imap, ino_t ino)
3210 {
3211 	u32 *dimap = imap->im_DBGdimap;
3212 	int w, b;
3213 	u32 m;
3214 	w = ino >> 5;
3215 	b = ino & 31;
3216 	m = 0x80000000 >> b;
3217 	assert(w < 64 * 256);
3218 	if (dimap[w] & m) {
3219 		printk("DEBUG diAlloc: duplicate alloc ino:0x%x\n", ino);
3220 	}
3221 	dimap[w] |= m;
3222 }
3223 
3224 /*
3225  *	DBGdiFree()
3226  */
3227 static void DBGdiFree(struct inomap * imap, ino_t ino)
3228 {
3229 	u32 *dimap = imap->im_DBGdimap;
3230 	int w, b;
3231 	u32 m;
3232 	w = ino >> 5;
3233 	b = ino & 31;
3234 	m = 0x80000000 >> b;
3235 	assert(w < 64 * 256);
3236 	if ((dimap[w] & m) == 0) {
3237 		printk("DEBUG diFree: duplicate free ino:0x%x\n", ino);
3238 	}
3239 	dimap[w] &= ~m;
3240 }
3241 
3242 static void dump_cp(struct inomap * ipimap, char *function, int line)
3243 {
3244 	printk("\n* ********* *\nControl Page %s %d\n", function, line);
3245 	printk("FreeIAG %d\tNextIAG %d\n", ipimap->im_freeiag,
3246 	       ipimap->im_nextiag);
3247 	printk("NumInos %d\tNumFree %d\n",
3248 	       atomic_read(&ipimap->im_numinos),
3249 	       atomic_read(&ipimap->im_numfree));
3250 	printk("AG InoFree %d\tAG ExtFree %d\n",
3251 	       ipimap->im_agctl[0].inofree, ipimap->im_agctl[0].extfree);
3252 	printk("AG NumInos %d\tAG NumFree %d\n",
3253 	       ipimap->im_agctl[0].numinos, ipimap->im_agctl[0].numfree);
3254 }
3255 
3256 static void dump_iag(struct iag * iag, char *function, int line)
3257 {
3258 	printk("\n* ********* *\nIAG %s %d\n", function, line);
3259 	printk("IagNum %d\tIAG Free %d\n", le32_to_cpu(iag->iagnum),
3260 	       le32_to_cpu(iag->iagfree));
3261 	printk("InoFreeFwd %d\tInoFreeBack %d\n",
3262 	       le32_to_cpu(iag->inofreefwd),
3263 	       le32_to_cpu(iag->inofreeback));
3264 	printk("ExtFreeFwd %d\tExtFreeBack %d\n",
3265 	       le32_to_cpu(iag->extfreefwd),
3266 	       le32_to_cpu(iag->extfreeback));
3267 	printk("NFreeInos %d\tNFreeExts %d\n", le32_to_cpu(iag->nfreeinos),
3268 	       le32_to_cpu(iag->nfreeexts));
3269 }
3270 #endif				/* _JFS_DEBUG_IMAP */
3271