2  *   Copyright (C) International Business Machines Corp., 2000-2004
16  *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
70  *	ip	- the inode of the file.
71  *	xlen	- requested extent length.
72  *	pno	- the starting page number with the file.
73  *	xp	- pointer to an xad.  on entry, xad describes an
75  *		  xaddr of the xad is non-zero.  on successful exit,
77  *	abnr	- bool indicating whether the newly allocated extent
81  *	0	- success
82  *	-EIO	- i/o error.
83  *	-ENOSPC	- insufficient disk resources.
86 extAlloc(struct inode *ip, s64 xlen, s64 pno, xad_t * xp, bool abnr)  in extAlloc()  argument
88 	struct jfs_sb_info *sbi = JFS_SBI(ip->i_sb);  in extAlloc()
93 	/* This blocks if we are low on resources */  in extAlloc()
94 	txBeginAnon(ip->i_sb);  in extAlloc()
97 	mutex_lock(&JFS_IP(ip)->commit_mutex);  in extAlloc()
104 	xoff = pno << sbi->l2nbperpage;  in extAlloc()
116 		 * extent if we can allocate the blocks immediately  in extAlloc()
120 		    abnr == ((xp->flag & XAD_NOTRECORDED) ? true : false))  in extAlloc()
124 		hint += (nxlen - 1);  in extAlloc()
127 	/* allocate the disk blocks for the extent.  initially, extBalloc()  in extAlloc()
128 	 * will try to allocate disk blocks for the requested size (xlen).  in extAlloc()
129 	 * if this fails (xlen contiguous free blocks not available), it'll  in extAlloc()
130 	 * try to allocate a smaller number of blocks (producing a smaller  in extAlloc()
131 	 * extent), with this smaller number of blocks consisting of the  in extAlloc()
132 	 * requested number of blocks rounded down to the next smaller  in extAlloc()
133 	 * power of 2 number (i.e. 16 -> 8).  it'll continue to round down  in extAlloc()
134 	 * and retry the allocation until the number of blocks to allocate  in extAlloc()
135 	 * is smaller than the number of blocks per page.  in extAlloc()
138 	if ((rc = extBalloc(ip, hint ? hint : INOHINT(ip), &nxlen, &nxaddr))) {  in extAlloc()
139 		mutex_unlock(&JFS_IP(ip)->commit_mutex);  in extAlloc()
143 	/* Allocate blocks to quota. */  in extAlloc()
144 	rc = dquot_alloc_block(ip, nxlen);  in extAlloc()
146 		dbFree(ip, nxaddr, (s64) nxlen);  in extAlloc()
147 		mutex_unlock(&JFS_IP(ip)->commit_mutex);  in extAlloc()
159 		rc = xtExtend(0, ip, xoff, (int) nxlen, 0);  in extAlloc()
161 		rc = xtInsert(0, ip, xflag, xoff, (int) nxlen, &nxaddr, 0);  in extAlloc()
164 	 * free the newly allocated blocks and return the error.  in extAlloc()
167 		dbFree(ip, nxaddr, nxlen);  in extAlloc()
168 		dquot_free_block(ip, nxlen);  in extAlloc()
169 		mutex_unlock(&JFS_IP(ip)->commit_mutex);  in extAlloc()
177 	xp->flag = xflag;  in extAlloc()
179 	mark_inode_dirty(ip);  in extAlloc()
181 	mutex_unlock(&JFS_IP(ip)->commit_mutex);  in extAlloc()
187 	if (test_and_clear_cflag(COMMIT_Synclist,ip))  in extAlloc()
188 		jfs_commit_inode(ip, 0);  in extAlloc()
202  *	ip	- the inode of the file.
203  *	cp	- cbuf for the partial backed last page.
204  *	xlen	- request size of the resulting extent.
205  *	xp	- pointer to an xad. on successful exit, the xad
207  *	abnr	- bool indicating whether the newly allocated extent
211  *	0	- success
212  *	-EIO	- i/o error.
213  *	-ENOSPC	- insufficient disk resources.
215 int extRealloc(struct inode *ip, s64 nxlen, xad_t * xp, bool abnr)  in extRealloc()  argument
217 	struct super_block *sb = ip->i_sb;  in extRealloc()
220 	int rc, nbperpage = JFS_SBI(sb)->nbperpage;  in extRealloc()
223 	/* This blocks if we are low on resources */  in extRealloc()
224 	txBeginAnon(ip->i_sb);  in extRealloc()
226 	mutex_lock(&JFS_IP(ip)->commit_mutex);  in extRealloc()
232 	 * number of blocks.  in extRealloc()
242 	if ((xp->flag & XAD_NOTRECORDED) && !abnr) {  in extRealloc()
243 		xp->flag = 0;  in extRealloc()
244 		if ((rc = xtUpdate(0, ip, xp)))  in extRealloc()
248 	/* try to allocated the request number of blocks for the  in extRealloc()
251 	 * try to allocate a new set of blocks large enough for the  in extRealloc()
256 	if ((rc = extBrealloc(ip, xaddr, xlen, &nxlen, &nxaddr)))  in extRealloc()
259 	/* Allocat blocks to quota. */  in extRealloc()
260 	rc = dquot_alloc_block(ip, nxlen);  in extRealloc()
262 		dbFree(ip, nxaddr, (s64) nxlen);  in extRealloc()
263 		mutex_unlock(&JFS_IP(ip)->commit_mutex);  in extRealloc()
267 	delta = nxlen - xlen;  in extRealloc()
280 	if (abnr && (!(xp->flag & XAD_NOTRECORDED)) && (nxlen > nbperpage)) {  in extRealloc()
282 		nextend = ntail - xlen;  in extRealloc()
283 		ninsert = nxlen - nbperpage;  in extRealloc()
291 		xflag = xp->flag;  in extRealloc()
300 		if ((rc = xtExtend(0, ip, xoff + xlen, (int) nextend, 0))) {  in extRealloc()
301 			dbFree(ip, xaddr + xlen, delta);  in extRealloc()
302 			dquot_free_block(ip, nxlen);  in extRealloc()
311 		if ((rc = xtTailgate(0, ip, xoff, (int) ntail, nxaddr, 0))) {  in extRealloc()
312 			dbFree(ip, nxaddr, nxlen);  in extRealloc()
313 			dquot_free_block(ip, nxlen);  in extRealloc()
321 		/* perform the insert.  if it fails, free the blocks  in extRealloc()
326 		if (xtInsert (0, ip, xflag, xoff + ntail, (int) ninsert,  in extRealloc()
328 			dbFree(ip, xaddr, (s64) ninsert);  in extRealloc()
339 	xp->flag = xflag;  in extRealloc()
341 	mark_inode_dirty(ip);  in extRealloc()
343 	mutex_unlock(&JFS_IP(ip)->commit_mutex);  in extRealloc()
355  *	ip	- the inode of the file.
356  *	offset  - file offset for which the hint is needed.
357  *	xp	- pointer to the xad that is to be filled in with
361  *	0	- success
362  *	-EIO	- i/o error.
364 int extHint(struct inode *ip, s64 offset, xad_t * xp)  in extHint()  argument
366 	struct super_block *sb = ip->i_sb;  in extHint()
367 	int nbperpage = JFS_SBI(sb)->nbperpage;  in extHint()
380 	prev = ((offset & ~POFFSET) >> JFS_SBI(sb)->l2bsize) - nbperpage;  in extHint()
387 	rc = xtLookup(ip, prev, nbperpage, &xflag, &xaddr, &xlen, 0);  in extHint()
391 			jfs_error(ip->i_sb, "corrupt xtree\n");  in extHint()
392 			rc = -EIO;  in extHint()
401 		xp->flag  = xflag & XAD_NOTRECORDED;  in extHint()
416  *	ip	- inode of the file.
417  *	cp	- cbuf of the file page.
420  *	0	- success
421  *	-EIO	- i/o error.
422  *	-ENOSPC	- insufficient disk resources.
424 int extRecord(struct inode *ip, xad_t * xp)  in extRecord()  argument
428 	txBeginAnon(ip->i_sb);  in extRecord()
430 	mutex_lock(&JFS_IP(ip)->commit_mutex);  in extRecord()
433 	rc = xtUpdate(0, ip, xp);  in extRecord()
435 	mutex_unlock(&JFS_IP(ip)->commit_mutex);  in extRecord()
448  *	ip	- the inode of the file.
449  *	cp	- cbuf of the file page represent the hole.
452  *	0	- success
453  *	-EIO	- i/o error.
454  *	-ENOSPC	- insufficient disk resources.
456 int extFill(struct inode *ip, xad_t * xp)  in extFill()  argument
458 	int rc, nbperpage = JFS_SBI(ip->i_sb)->nbperpage;  in extFill()
459 	s64 blkno = offsetXAD(xp) >> ip->i_blkbits;  in extFill()
461 //	assert(ISSPARSE(ip));  in extFill()
467 	if ((rc = extAlloc(ip, nbperpage, blkno, xp, false)))  in extFill()
480  * FUNCTION:	allocate disk blocks to form an extent.
482  *		initially, we will try to allocate disk blocks for the
484  *		contiguous free blocks not available), we'll try to allocate
485  *		a smaller number of blocks (producing a smaller extent), with
486  *		this smaller number of blocks consisting of the requested
487  *		number of blocks rounded down to the next smaller power of 2
488  *		number (i.e. 16 -> 8).  we'll continue to round down and
489  *		retry the allocation until the number of blocks to allocate
490  *		is smaller than the number of blocks per page.
493  *	ip	 - the inode of the file.
494  *	hint	 - disk block number to be used as an allocation hint.
495  *	*nblocks - pointer to an s64 value.  on entry, this value specifies
497  *		   exit, this value is set to the number of blocks actually
499  *	blkno	 - pointer to a block address that is filled in on successful
504  *	0	- success
505  *	-EIO	- i/o error.
506  *	-ENOSPC	- insufficient disk resources.
509 extBalloc(struct inode *ip, s64 hint, s64 * nblocks, s64 * blkno)  in extBalloc()  argument
511 	struct jfs_inode_info *ji = JFS_IP(ip);  in extBalloc()
512 	struct jfs_sb_info *sbi = JFS_SBI(ip->i_sb);  in extBalloc()
514 	int rc, nbperpage = sbi->nbperpage;  in extBalloc()
515 	struct bmap *bmp = sbi->bmap;  in extBalloc()
518 	/* get the number of blocks to initially attempt to allocate.  in extBalloc()
519 	 * we'll first try the number of blocks requested unless this  in extBalloc()
521 	 * blocks in the map. in that case, we'll start off with the  in extBalloc()
524 	max = (s64) 1 << bmp->db_maxfreebud;  in extBalloc()
530 	/* try to allocate blocks */  in extBalloc()
531 	while ((rc = dbAlloc(ip, hint, nb, &daddr)) != 0) {  in extBalloc()
535 		if (rc != -ENOSPC)  in extBalloc()
549 	if (S_ISREG(ip->i_mode) && (ji->fileset == FILESYSTEM_I)) {  in extBalloc()
551 		spin_lock_irq(&ji->ag_lock);  in extBalloc()
552 		if (ji->active_ag == -1) {  in extBalloc()
553 			atomic_inc(&bmp->db_active[ag]);  in extBalloc()
554 			ji->active_ag = ag;  in extBalloc()
555 		} else if (ji->active_ag != ag) {  in extBalloc()
556 			atomic_dec(&bmp->db_active[ji->active_ag]);  in extBalloc()
557 			atomic_inc(&bmp->db_active[ag]);  in extBalloc()
558 			ji->active_ag = ag;  in extBalloc()
560 		spin_unlock_irq(&ji->ag_lock);  in extBalloc()
575  *		to a new set of blocks.  If moving the extent, we initially
576  *		will try to allocate disk blocks for the requested size
577  *		(newnblks).  if this fails (new contiguous free blocks not
579  *		blocks (producing a smaller extent), with this smaller
580  *		number of blocks consisting of the requested number of
581  *		blocks rounded down to the next smaller power of 2
582  *		number (i.e. 16 -> 8).  We'll continue to round down and
583  *		retry the allocation until the number of blocks to allocate
584  *		is smaller than the number of blocks per page.
587  *	ip	 - the inode of the file.
588  *	blkno	 - starting block number of the extents current allocation.
589  *	nblks	 - number of blocks within the extents current allocation.
590  *	newnblks - pointer to a s64 value.  on entry, this value is the
591  *		   the new desired extent size (number of blocks).  on
593  *		   new size (new number of blocks).
594  *	newblkno - the starting block number of the extents new allocation.
597  *	0	- success
598  *	-EIO	- i/o error.
599  *	-ENOSPC	- insufficient disk resources.
602 extBrealloc(struct inode *ip,  in extBrealloc()  argument
608 	if ((rc = dbExtend(ip, blkno, nblks, *newnblks - nblks)) == 0) {  in extBrealloc()
612 		if (rc != -ENOSPC)  in extBrealloc()
617 	 * try to move the extent to a new set of blocks.  in extBrealloc()
619 	return (extBalloc(ip, blkno, newnblks, newblkno));  in extBrealloc()
627  * FUNCTION:	round down a specified number of blocks to the next
631  *	nb	- the inode of the file.
646 	i = 63 - i;  in extRoundDown()
648 	k = ((k - 1) & nb) ? k : k >> 1;  in extRoundDown()