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  1// SPDX-License-Identifier: GPL-2.0
  2/*
  3 *  linux/fs/ufs/balloc.c
  4 *
  5 * Copyright (C) 1998
  6 * Daniel Pirkl <daniel.pirkl@email.cz>
  7 * Charles University, Faculty of Mathematics and Physics
  8 *
  9 * UFS2 write support Evgeniy Dushistov <dushistov@mail.ru>, 2007
 10 */
 11
 12#include <linux/fs.h>
 13#include <linux/stat.h>
 14#include <linux/time.h>
 15#include <linux/string.h>
 16#include <linux/buffer_head.h>
 17#include <linux/capability.h>
 18#include <linux/bitops.h>
 19#include <linux/bio.h>
 20#include <asm/byteorder.h>
 21
 22#include "ufs_fs.h"
 23#include "ufs.h"
 24#include "swab.h"
 25#include "util.h"
 26
 27#define INVBLOCK ((u64)-1L)
 28
 29static u64 ufs_add_fragments(struct inode *, u64, unsigned, unsigned);
 30static u64 ufs_alloc_fragments(struct inode *, unsigned, u64, unsigned, int *);
 31static u64 ufs_alloccg_block(struct inode *, struct ufs_cg_private_info *, u64, int *);
 32static u64 ufs_bitmap_search (struct super_block *, struct ufs_cg_private_info *, u64, unsigned);
 33static unsigned char ufs_fragtable_8fpb[], ufs_fragtable_other[];
 34static void ufs_clusteracct(struct super_block *, struct ufs_cg_private_info *, unsigned, int);
 35
 36/*
 37 * Free 'count' fragments from fragment number 'fragment'
 38 */
 39void ufs_free_fragments(struct inode *inode, u64 fragment, unsigned count)
 40{
 41	struct super_block * sb;
 42	struct ufs_sb_private_info * uspi;
 43	struct ufs_cg_private_info * ucpi;
 44	struct ufs_cylinder_group * ucg;
 45	unsigned cgno, bit, end_bit, bbase, blkmap, i;
 46	u64 blkno;
 47	
 48	sb = inode->i_sb;
 49	uspi = UFS_SB(sb)->s_uspi;
 50	
 51	UFSD("ENTER, fragment %llu, count %u\n",
 52	     (unsigned long long)fragment, count);
 53	
 54	if (ufs_fragnum(fragment) + count > uspi->s_fpg)
 55		ufs_error (sb, "ufs_free_fragments", "internal error");
 56
 57	mutex_lock(&UFS_SB(sb)->s_lock);
 58	
 59	cgno = ufs_dtog(uspi, fragment);
 60	bit = ufs_dtogd(uspi, fragment);
 61	if (cgno >= uspi->s_ncg) {
 62		ufs_panic (sb, "ufs_free_fragments", "freeing blocks are outside device");
 63		goto failed;
 64	}
 65		
 66	ucpi = ufs_load_cylinder (sb, cgno);
 67	if (!ucpi) 
 68		goto failed;
 69	ucg = ubh_get_ucg (UCPI_UBH(ucpi));
 70	if (!ufs_cg_chkmagic(sb, ucg)) {
 71		ufs_panic (sb, "ufs_free_fragments", "internal error, bad magic number on cg %u", cgno);
 72		goto failed;
 73	}
 74
 75	end_bit = bit + count;
 76	bbase = ufs_blknum (bit);
 77	blkmap = ubh_blkmap (UCPI_UBH(ucpi), ucpi->c_freeoff, bbase);
 78	ufs_fragacct (sb, blkmap, ucg->cg_frsum, -1);
 79	for (i = bit; i < end_bit; i++) {
 80		if (ubh_isclr (UCPI_UBH(ucpi), ucpi->c_freeoff, i))
 81			ubh_setbit (UCPI_UBH(ucpi), ucpi->c_freeoff, i);
 82		else 
 83			ufs_error (sb, "ufs_free_fragments",
 84				   "bit already cleared for fragment %u", i);
 85	}
 86
 87	inode_sub_bytes(inode, count << uspi->s_fshift);
 88	fs32_add(sb, &ucg->cg_cs.cs_nffree, count);
 89	uspi->cs_total.cs_nffree += count;
 90	fs32_add(sb, &UFS_SB(sb)->fs_cs(cgno).cs_nffree, count);
 91	blkmap = ubh_blkmap (UCPI_UBH(ucpi), ucpi->c_freeoff, bbase);
 92	ufs_fragacct(sb, blkmap, ucg->cg_frsum, 1);
 93
 94	/*
 95	 * Trying to reassemble free fragments into block
 96	 */
 97	blkno = ufs_fragstoblks (bbase);
 98	if (ubh_isblockset(UCPI_UBH(ucpi), ucpi->c_freeoff, blkno)) {
 99		fs32_sub(sb, &ucg->cg_cs.cs_nffree, uspi->s_fpb);
100		uspi->cs_total.cs_nffree -= uspi->s_fpb;
101		fs32_sub(sb, &UFS_SB(sb)->fs_cs(cgno).cs_nffree, uspi->s_fpb);
102		if ((UFS_SB(sb)->s_flags & UFS_CG_MASK) == UFS_CG_44BSD)
103			ufs_clusteracct (sb, ucpi, blkno, 1);
104		fs32_add(sb, &ucg->cg_cs.cs_nbfree, 1);
105		uspi->cs_total.cs_nbfree++;
106		fs32_add(sb, &UFS_SB(sb)->fs_cs(cgno).cs_nbfree, 1);
107		if (uspi->fs_magic != UFS2_MAGIC) {
108			unsigned cylno = ufs_cbtocylno (bbase);
109
110			fs16_add(sb, &ubh_cg_blks(ucpi, cylno,
111						  ufs_cbtorpos(bbase)), 1);
112			fs32_add(sb, &ubh_cg_blktot(ucpi, cylno), 1);
113		}
114	}
115	
116	ubh_mark_buffer_dirty (USPI_UBH(uspi));
117	ubh_mark_buffer_dirty (UCPI_UBH(ucpi));
118	if (sb->s_flags & SB_SYNCHRONOUS)
119		ubh_sync_block(UCPI_UBH(ucpi));
120	ufs_mark_sb_dirty(sb);
121
122	mutex_unlock(&UFS_SB(sb)->s_lock);
123	UFSD("EXIT\n");
124	return;
125
126failed:
127	mutex_unlock(&UFS_SB(sb)->s_lock);
128	UFSD("EXIT (FAILED)\n");
129	return;
130}
131
132/*
133 * Free 'count' fragments from fragment number 'fragment' (free whole blocks)
134 */
135void ufs_free_blocks(struct inode *inode, u64 fragment, unsigned count)
136{
137	struct super_block * sb;
138	struct ufs_sb_private_info * uspi;
139	struct ufs_cg_private_info * ucpi;
140	struct ufs_cylinder_group * ucg;
141	unsigned overflow, cgno, bit, end_bit, i;
142	u64 blkno;
143	
144	sb = inode->i_sb;
145	uspi = UFS_SB(sb)->s_uspi;
146
147	UFSD("ENTER, fragment %llu, count %u\n",
148	     (unsigned long long)fragment, count);
149	
150	if ((fragment & uspi->s_fpbmask) || (count & uspi->s_fpbmask)) {
151		ufs_error (sb, "ufs_free_blocks", "internal error, "
152			   "fragment %llu, count %u\n",
153			   (unsigned long long)fragment, count);
154		goto failed;
155	}
156
157	mutex_lock(&UFS_SB(sb)->s_lock);
158	
159do_more:
160	overflow = 0;
161	cgno = ufs_dtog(uspi, fragment);
162	bit = ufs_dtogd(uspi, fragment);
163	if (cgno >= uspi->s_ncg) {
164		ufs_panic (sb, "ufs_free_blocks", "freeing blocks are outside device");
165		goto failed_unlock;
166	}
167	end_bit = bit + count;
168	if (end_bit > uspi->s_fpg) {
169		overflow = bit + count - uspi->s_fpg;
170		count -= overflow;
171		end_bit -= overflow;
172	}
173
174	ucpi = ufs_load_cylinder (sb, cgno);
175	if (!ucpi) 
176		goto failed_unlock;
177	ucg = ubh_get_ucg (UCPI_UBH(ucpi));
178	if (!ufs_cg_chkmagic(sb, ucg)) {
179		ufs_panic (sb, "ufs_free_blocks", "internal error, bad magic number on cg %u", cgno);
180		goto failed_unlock;
181	}
182
183	for (i = bit; i < end_bit; i += uspi->s_fpb) {
184		blkno = ufs_fragstoblks(i);
185		if (ubh_isblockset(UCPI_UBH(ucpi), ucpi->c_freeoff, blkno)) {
186			ufs_error(sb, "ufs_free_blocks", "freeing free fragment");
187		}
188		ubh_setblock(UCPI_UBH(ucpi), ucpi->c_freeoff, blkno);
189		inode_sub_bytes(inode, uspi->s_fpb << uspi->s_fshift);
190		if ((UFS_SB(sb)->s_flags & UFS_CG_MASK) == UFS_CG_44BSD)
191			ufs_clusteracct (sb, ucpi, blkno, 1);
192
193		fs32_add(sb, &ucg->cg_cs.cs_nbfree, 1);
194		uspi->cs_total.cs_nbfree++;
195		fs32_add(sb, &UFS_SB(sb)->fs_cs(cgno).cs_nbfree, 1);
196
197		if (uspi->fs_magic != UFS2_MAGIC) {
198			unsigned cylno = ufs_cbtocylno(i);
199
200			fs16_add(sb, &ubh_cg_blks(ucpi, cylno,
201						  ufs_cbtorpos(i)), 1);
202			fs32_add(sb, &ubh_cg_blktot(ucpi, cylno), 1);
203		}
204	}
205
206	ubh_mark_buffer_dirty (USPI_UBH(uspi));
207	ubh_mark_buffer_dirty (UCPI_UBH(ucpi));
208	if (sb->s_flags & SB_SYNCHRONOUS)
209		ubh_sync_block(UCPI_UBH(ucpi));
210
211	if (overflow) {
212		fragment += count;
213		count = overflow;
214		goto do_more;
215	}
216
217	ufs_mark_sb_dirty(sb);
218	mutex_unlock(&UFS_SB(sb)->s_lock);
219	UFSD("EXIT\n");
220	return;
221
222failed_unlock:
223	mutex_unlock(&UFS_SB(sb)->s_lock);
224failed:
225	UFSD("EXIT (FAILED)\n");
226	return;
227}
228
229/*
230 * Modify inode page cache in such way:
231 * have - blocks with b_blocknr equal to oldb...oldb+count-1
232 * get - blocks with b_blocknr equal to newb...newb+count-1
233 * also we suppose that oldb...oldb+count-1 blocks
234 * situated at the end of file.
235 *
236 * We can come here from ufs_writepage or ufs_prepare_write,
237 * locked_page is argument of these functions, so we already lock it.
238 */
239static void ufs_change_blocknr(struct inode *inode, sector_t beg,
240			       unsigned int count, sector_t oldb,
241			       sector_t newb, struct page *locked_page)
242{
243	const unsigned blks_per_page =
244		1 << (PAGE_SHIFT - inode->i_blkbits);
245	const unsigned mask = blks_per_page - 1;
246	struct address_space * const mapping = inode->i_mapping;
247	pgoff_t index, cur_index, last_index;
248	unsigned pos, j, lblock;
249	sector_t end, i;
250	struct page *page;
251	struct buffer_head *head, *bh;
252
253	UFSD("ENTER, ino %lu, count %u, oldb %llu, newb %llu\n",
254	      inode->i_ino, count,
255	     (unsigned long long)oldb, (unsigned long long)newb);
256
257	BUG_ON(!locked_page);
258	BUG_ON(!PageLocked(locked_page));
259
260	cur_index = locked_page->index;
261	end = count + beg;
262	last_index = end >> (PAGE_SHIFT - inode->i_blkbits);
263	for (i = beg; i < end; i = (i | mask) + 1) {
264		index = i >> (PAGE_SHIFT - inode->i_blkbits);
265
266		if (likely(cur_index != index)) {
267			page = ufs_get_locked_page(mapping, index);
268			if (!page)/* it was truncated */
269				continue;
270			if (IS_ERR(page)) {/* or EIO */
271				ufs_error(inode->i_sb, __func__,
272					  "read of page %llu failed\n",
273					  (unsigned long long)index);
274				continue;
275			}
276		} else
277			page = locked_page;
278
279		head = page_buffers(page);
280		bh = head;
281		pos = i & mask;
282		for (j = 0; j < pos; ++j)
283			bh = bh->b_this_page;
284
285
286		if (unlikely(index == last_index))
287			lblock = end & mask;
288		else
289			lblock = blks_per_page;
290
291		do {
292			if (j >= lblock)
293				break;
294			pos = (i - beg) + j;
295
296			if (!buffer_mapped(bh))
297					map_bh(bh, inode->i_sb, oldb + pos);
298			if (!buffer_uptodate(bh)) {
299				ll_rw_block(REQ_OP_READ, 0, 1, &bh);
300				wait_on_buffer(bh);
301				if (!buffer_uptodate(bh)) {
302					ufs_error(inode->i_sb, __func__,
303						  "read of block failed\n");
304					break;
305				}
306			}
307
308			UFSD(" change from %llu to %llu, pos %u\n",
309			     (unsigned long long)(pos + oldb),
310			     (unsigned long long)(pos + newb), pos);
311
312			bh->b_blocknr = newb + pos;
313			clean_bdev_bh_alias(bh);
314			mark_buffer_dirty(bh);
315			++j;
316			bh = bh->b_this_page;
317		} while (bh != head);
318
319		if (likely(cur_index != index))
320			ufs_put_locked_page(page);
321 	}
322	UFSD("EXIT\n");
323}
324
325static void ufs_clear_frags(struct inode *inode, sector_t beg, unsigned int n,
326			    int sync)
327{
328	struct buffer_head *bh;
329	sector_t end = beg + n;
330
331	for (; beg < end; ++beg) {
332		bh = sb_getblk(inode->i_sb, beg);
333		lock_buffer(bh);
334		memset(bh->b_data, 0, inode->i_sb->s_blocksize);
335		set_buffer_uptodate(bh);
336		mark_buffer_dirty(bh);
337		unlock_buffer(bh);
338		if (IS_SYNC(inode) || sync)
339			sync_dirty_buffer(bh);
340		brelse(bh);
341	}
342}
343
344u64 ufs_new_fragments(struct inode *inode, void *p, u64 fragment,
345			   u64 goal, unsigned count, int *err,
346			   struct page *locked_page)
347{
348	struct super_block * sb;
349	struct ufs_sb_private_info * uspi;
350	struct ufs_super_block_first * usb1;
351	unsigned cgno, oldcount, newcount;
352	u64 tmp, request, result;
353	
354	UFSD("ENTER, ino %lu, fragment %llu, goal %llu, count %u\n",
355	     inode->i_ino, (unsigned long long)fragment,
356	     (unsigned long long)goal, count);
357	
358	sb = inode->i_sb;
359	uspi = UFS_SB(sb)->s_uspi;
360	usb1 = ubh_get_usb_first(uspi);
361	*err = -ENOSPC;
362
363	mutex_lock(&UFS_SB(sb)->s_lock);
364	tmp = ufs_data_ptr_to_cpu(sb, p);
365
366	if (count + ufs_fragnum(fragment) > uspi->s_fpb) {
367		ufs_warning(sb, "ufs_new_fragments", "internal warning"
368			    " fragment %llu, count %u",
369			    (unsigned long long)fragment, count);
370		count = uspi->s_fpb - ufs_fragnum(fragment); 
371	}
372	oldcount = ufs_fragnum (fragment);
373	newcount = oldcount + count;
374
375	/*
376	 * Somebody else has just allocated our fragments
377	 */
378	if (oldcount) {
379		if (!tmp) {
380			ufs_error(sb, "ufs_new_fragments", "internal error, "
381				  "fragment %llu, tmp %llu\n",
382				  (unsigned long long)fragment,
383				  (unsigned long long)tmp);
384			mutex_unlock(&UFS_SB(sb)->s_lock);
385			return INVBLOCK;
386		}
387		if (fragment < UFS_I(inode)->i_lastfrag) {
388			UFSD("EXIT (ALREADY ALLOCATED)\n");
389			mutex_unlock(&UFS_SB(sb)->s_lock);
390			return 0;
391		}
392	}
393	else {
394		if (tmp) {
395			UFSD("EXIT (ALREADY ALLOCATED)\n");
396			mutex_unlock(&UFS_SB(sb)->s_lock);
397			return 0;
398		}
399	}
400
401	/*
402	 * There is not enough space for user on the device
403	 */
404	if (unlikely(ufs_freefrags(uspi) <= uspi->s_root_blocks)) {
405		if (!capable(CAP_SYS_RESOURCE)) {
406			mutex_unlock(&UFS_SB(sb)->s_lock);
407			UFSD("EXIT (FAILED)\n");
408			return 0;
409		}
410	}
411
412	if (goal >= uspi->s_size) 
413		goal = 0;
414	if (goal == 0) 
415		cgno = ufs_inotocg (inode->i_ino);
416	else
417		cgno = ufs_dtog(uspi, goal);
418	 
419	/*
420	 * allocate new fragment
421	 */
422	if (oldcount == 0) {
423		result = ufs_alloc_fragments (inode, cgno, goal, count, err);
424		if (result) {
425			ufs_clear_frags(inode, result + oldcount,
426					newcount - oldcount, locked_page != NULL);
427			*err = 0;
428			write_seqlock(&UFS_I(inode)->meta_lock);
429			ufs_cpu_to_data_ptr(sb, p, result);
430			UFS_I(inode)->i_lastfrag =
431				max(UFS_I(inode)->i_lastfrag, fragment + count);
432			write_sequnlock(&UFS_I(inode)->meta_lock);
433		}
434		mutex_unlock(&UFS_SB(sb)->s_lock);
435		UFSD("EXIT, result %llu\n", (unsigned long long)result);
436		return result;
437	}
438
439	/*
440	 * resize block
441	 */
442	result = ufs_add_fragments(inode, tmp, oldcount, newcount);
443	if (result) {
444		*err = 0;
445		read_seqlock_excl(&UFS_I(inode)->meta_lock);
446		UFS_I(inode)->i_lastfrag = max(UFS_I(inode)->i_lastfrag,
447						fragment + count);
448		read_sequnlock_excl(&UFS_I(inode)->meta_lock);
449		ufs_clear_frags(inode, result + oldcount, newcount - oldcount,
450				locked_page != NULL);
451		mutex_unlock(&UFS_SB(sb)->s_lock);
452		UFSD("EXIT, result %llu\n", (unsigned long long)result);
453		return result;
454	}
455
456	/*
457	 * allocate new block and move data
458	 */
459	if (fs32_to_cpu(sb, usb1->fs_optim) == UFS_OPTSPACE) {
460		request = newcount;
461		if (uspi->cs_total.cs_nffree < uspi->s_space_to_time)
462			usb1->fs_optim = cpu_to_fs32(sb, UFS_OPTTIME);
463	} else {
464		request = uspi->s_fpb;
465		if (uspi->cs_total.cs_nffree > uspi->s_time_to_space)
466			usb1->fs_optim = cpu_to_fs32(sb, UFS_OPTSPACE);
467	}
468	result = ufs_alloc_fragments (inode, cgno, goal, request, err);
469	if (result) {
470		ufs_clear_frags(inode, result + oldcount, newcount - oldcount,
471				locked_page != NULL);
472		mutex_unlock(&UFS_SB(sb)->s_lock);
473		ufs_change_blocknr(inode, fragment - oldcount, oldcount,
474				   uspi->s_sbbase + tmp,
475				   uspi->s_sbbase + result, locked_page);
476		*err = 0;
477		write_seqlock(&UFS_I(inode)->meta_lock);
478		ufs_cpu_to_data_ptr(sb, p, result);
479		UFS_I(inode)->i_lastfrag = max(UFS_I(inode)->i_lastfrag,
480						fragment + count);
481		write_sequnlock(&UFS_I(inode)->meta_lock);
482		if (newcount < request)
483			ufs_free_fragments (inode, result + newcount, request - newcount);
484		ufs_free_fragments (inode, tmp, oldcount);
485		UFSD("EXIT, result %llu\n", (unsigned long long)result);
486		return result;
487	}
488
489	mutex_unlock(&UFS_SB(sb)->s_lock);
490	UFSD("EXIT (FAILED)\n");
491	return 0;
492}		
493
494static bool try_add_frags(struct inode *inode, unsigned frags)
495{
496	unsigned size = frags * i_blocksize(inode);
497	spin_lock(&inode->i_lock);
498	__inode_add_bytes(inode, size);
499	if (unlikely((u32)inode->i_blocks != inode->i_blocks)) {
500		__inode_sub_bytes(inode, size);
501		spin_unlock(&inode->i_lock);
502		return false;
503	}
504	spin_unlock(&inode->i_lock);
505	return true;
506}
507
508static u64 ufs_add_fragments(struct inode *inode, u64 fragment,
509			     unsigned oldcount, unsigned newcount)
510{
511	struct super_block * sb;
512	struct ufs_sb_private_info * uspi;
513	struct ufs_cg_private_info * ucpi;
514	struct ufs_cylinder_group * ucg;
515	unsigned cgno, fragno, fragoff, count, fragsize, i;
516	
517	UFSD("ENTER, fragment %llu, oldcount %u, newcount %u\n",
518	     (unsigned long long)fragment, oldcount, newcount);
519	
520	sb = inode->i_sb;
521	uspi = UFS_SB(sb)->s_uspi;
522	count = newcount - oldcount;
523	
524	cgno = ufs_dtog(uspi, fragment);
525	if (fs32_to_cpu(sb, UFS_SB(sb)->fs_cs(cgno).cs_nffree) < count)
526		return 0;
527	if ((ufs_fragnum (fragment) + newcount) > uspi->s_fpb)
528		return 0;
529	ucpi = ufs_load_cylinder (sb, cgno);
530	if (!ucpi)
531		return 0;
532	ucg = ubh_get_ucg (UCPI_UBH(ucpi));
533	if (!ufs_cg_chkmagic(sb, ucg)) {
534		ufs_panic (sb, "ufs_add_fragments",
535			"internal error, bad magic number on cg %u", cgno);
536		return 0;
537	}
538
539	fragno = ufs_dtogd(uspi, fragment);
540	fragoff = ufs_fragnum (fragno);
541	for (i = oldcount; i < newcount; i++)
542		if (ubh_isclr (UCPI_UBH(ucpi), ucpi->c_freeoff, fragno + i))
543			return 0;
544
545	if (!try_add_frags(inode, count))
546		return 0;
547	/*
548	 * Block can be extended
549	 */
550	ucg->cg_time = cpu_to_fs32(sb, get_seconds());
551	for (i = newcount; i < (uspi->s_fpb - fragoff); i++)
552		if (ubh_isclr (UCPI_UBH(ucpi), ucpi->c_freeoff, fragno + i))
553			break;
554	fragsize = i - oldcount;
555	if (!fs32_to_cpu(sb, ucg->cg_frsum[fragsize]))
556		ufs_panic (sb, "ufs_add_fragments",
557			"internal error or corrupted bitmap on cg %u", cgno);
558	fs32_sub(sb, &ucg->cg_frsum[fragsize], 1);
559	if (fragsize != count)
560		fs32_add(sb, &ucg->cg_frsum[fragsize - count], 1);
561	for (i = oldcount; i < newcount; i++)
562		ubh_clrbit (UCPI_UBH(ucpi), ucpi->c_freeoff, fragno + i);
563
564	fs32_sub(sb, &ucg->cg_cs.cs_nffree, count);
565	fs32_sub(sb, &UFS_SB(sb)->fs_cs(cgno).cs_nffree, count);
566	uspi->cs_total.cs_nffree -= count;
567	
568	ubh_mark_buffer_dirty (USPI_UBH(uspi));
569	ubh_mark_buffer_dirty (UCPI_UBH(ucpi));
570	if (sb->s_flags & SB_SYNCHRONOUS)
571		ubh_sync_block(UCPI_UBH(ucpi));
572	ufs_mark_sb_dirty(sb);
573
574	UFSD("EXIT, fragment %llu\n", (unsigned long long)fragment);
575	
576	return fragment;
577}
578
579#define UFS_TEST_FREE_SPACE_CG \
580	ucg = (struct ufs_cylinder_group *) UFS_SB(sb)->s_ucg[cgno]->b_data; \
581	if (fs32_to_cpu(sb, ucg->cg_cs.cs_nbfree)) \
582		goto cg_found; \
583	for (k = count; k < uspi->s_fpb; k++) \
584		if (fs32_to_cpu(sb, ucg->cg_frsum[k])) \
585			goto cg_found; 
586
587static u64 ufs_alloc_fragments(struct inode *inode, unsigned cgno,
588			       u64 goal, unsigned count, int *err)
589{
590	struct super_block * sb;
591	struct ufs_sb_private_info * uspi;
592	struct ufs_cg_private_info * ucpi;
593	struct ufs_cylinder_group * ucg;
594	unsigned oldcg, i, j, k, allocsize;
595	u64 result;
596	
597	UFSD("ENTER, ino %lu, cgno %u, goal %llu, count %u\n",
598	     inode->i_ino, cgno, (unsigned long long)goal, count);
599
600	sb = inode->i_sb;
601	uspi = UFS_SB(sb)->s_uspi;
602	oldcg = cgno;
603	
604	/*
605	 * 1. searching on preferred cylinder group
606	 */
607	UFS_TEST_FREE_SPACE_CG
608
609	/*
610	 * 2. quadratic rehash
611	 */
612	for (j = 1; j < uspi->s_ncg; j *= 2) {
613		cgno += j;
614		if (cgno >= uspi->s_ncg) 
615			cgno -= uspi->s_ncg;
616		UFS_TEST_FREE_SPACE_CG
617	}
618
619	/*
620	 * 3. brute force search
621	 * We start at i = 2 ( 0 is checked at 1.step, 1 at 2.step )
622	 */
623	cgno = (oldcg + 1) % uspi->s_ncg;
624	for (j = 2; j < uspi->s_ncg; j++) {
625		cgno++;
626		if (cgno >= uspi->s_ncg)
627			cgno = 0;
628		UFS_TEST_FREE_SPACE_CG
629	}
630	
631	UFSD("EXIT (FAILED)\n");
632	return 0;
633
634cg_found:
635	ucpi = ufs_load_cylinder (sb, cgno);
636	if (!ucpi)
637		return 0;
638	ucg = ubh_get_ucg (UCPI_UBH(ucpi));
639	if (!ufs_cg_chkmagic(sb, ucg)) 
640		ufs_panic (sb, "ufs_alloc_fragments",
641			"internal error, bad magic number on cg %u", cgno);
642	ucg->cg_time = cpu_to_fs32(sb, get_seconds());
643
644	if (count == uspi->s_fpb) {
645		result = ufs_alloccg_block (inode, ucpi, goal, err);
646		if (result == INVBLOCK)
647			return 0;
648		goto succed;
649	}
650
651	for (allocsize = count; allocsize < uspi->s_fpb; allocsize++)
652		if (fs32_to_cpu(sb, ucg->cg_frsum[allocsize]) != 0)
653			break;
654	
655	if (allocsize == uspi->s_fpb) {
656		result = ufs_alloccg_block (inode, ucpi, goal, err);
657		if (result == INVBLOCK)
658			return 0;
659		goal = ufs_dtogd(uspi, result);
660		for (i = count; i < uspi->s_fpb; i++)
661			ubh_setbit (UCPI_UBH(ucpi), ucpi->c_freeoff, goal + i);
662		i = uspi->s_fpb - count;
663
664		inode_sub_bytes(inode, i << uspi->s_fshift);
665		fs32_add(sb, &ucg->cg_cs.cs_nffree, i);
666		uspi->cs_total.cs_nffree += i;
667		fs32_add(sb, &UFS_SB(sb)->fs_cs(cgno).cs_nffree, i);
668		fs32_add(sb, &ucg->cg_frsum[i], 1);
669		goto succed;
670	}
671
672	result = ufs_bitmap_search (sb, ucpi, goal, allocsize);
673	if (result == INVBLOCK)
674		return 0;
675	if (!try_add_frags(inode, count))
676		return 0;
677	for (i = 0; i < count; i++)
678		ubh_clrbit (UCPI_UBH(ucpi), ucpi->c_freeoff, result + i);
679	
680	fs32_sub(sb, &ucg->cg_cs.cs_nffree, count);
681	uspi->cs_total.cs_nffree -= count;
682	fs32_sub(sb, &UFS_SB(sb)->fs_cs(cgno).cs_nffree, count);
683	fs32_sub(sb, &ucg->cg_frsum[allocsize], 1);
684
685	if (count != allocsize)
686		fs32_add(sb, &ucg->cg_frsum[allocsize - count], 1);
687
688succed:
689	ubh_mark_buffer_dirty (USPI_UBH(uspi));
690	ubh_mark_buffer_dirty (UCPI_UBH(ucpi));
691	if (sb->s_flags & SB_SYNCHRONOUS)
692		ubh_sync_block(UCPI_UBH(ucpi));
693	ufs_mark_sb_dirty(sb);
694
695	result += cgno * uspi->s_fpg;
696	UFSD("EXIT3, result %llu\n", (unsigned long long)result);
697	return result;
698}
699
700static u64 ufs_alloccg_block(struct inode *inode,
701			     struct ufs_cg_private_info *ucpi,
702			     u64 goal, int *err)
703{
704	struct super_block * sb;
705	struct ufs_sb_private_info * uspi;
706	struct ufs_cylinder_group * ucg;
707	u64 result, blkno;
708
709	UFSD("ENTER, goal %llu\n", (unsigned long long)goal);
710
711	sb = inode->i_sb;
712	uspi = UFS_SB(sb)->s_uspi;
713	ucg = ubh_get_ucg(UCPI_UBH(ucpi));
714
715	if (goal == 0) {
716		goal = ucpi->c_rotor;
717		goto norot;
718	}
719	goal = ufs_blknum (goal);
720	goal = ufs_dtogd(uspi, goal);
721	
722	/*
723	 * If the requested block is available, use it.
724	 */
725	if (ubh_isblockset(UCPI_UBH(ucpi), ucpi->c_freeoff, ufs_fragstoblks(goal))) {
726		result = goal;
727		goto gotit;
728	}
729	
730norot:	
731	result = ufs_bitmap_search (sb, ucpi, goal, uspi->s_fpb);
732	if (result == INVBLOCK)
733		return INVBLOCK;
734	ucpi->c_rotor = result;
735gotit:
736	if (!try_add_frags(inode, uspi->s_fpb))
737		return 0;
738	blkno = ufs_fragstoblks(result);
739	ubh_clrblock (UCPI_UBH(ucpi), ucpi->c_freeoff, blkno);
740	if ((UFS_SB(sb)->s_flags & UFS_CG_MASK) == UFS_CG_44BSD)
741		ufs_clusteracct (sb, ucpi, blkno, -1);
742
743	fs32_sub(sb, &ucg->cg_cs.cs_nbfree, 1);
744	uspi->cs_total.cs_nbfree--;
745	fs32_sub(sb, &UFS_SB(sb)->fs_cs(ucpi->c_cgx).cs_nbfree, 1);
746
747	if (uspi->fs_magic != UFS2_MAGIC) {
748		unsigned cylno = ufs_cbtocylno((unsigned)result);
749
750		fs16_sub(sb, &ubh_cg_blks(ucpi, cylno,
751					  ufs_cbtorpos((unsigned)result)), 1);
752		fs32_sub(sb, &ubh_cg_blktot(ucpi, cylno), 1);
753	}
754	
755	UFSD("EXIT, result %llu\n", (unsigned long long)result);
756
757	return result;
758}
759
760static unsigned ubh_scanc(struct ufs_sb_private_info *uspi,
761			  struct ufs_buffer_head *ubh,
762			  unsigned begin, unsigned size,
763			  unsigned char *table, unsigned char mask)
764{
765	unsigned rest, offset;
766	unsigned char *cp;
767	
768
769	offset = begin & ~uspi->s_fmask;
770	begin >>= uspi->s_fshift;
771	for (;;) {
772		if ((offset + size) < uspi->s_fsize)
773			rest = size;
774		else
775			rest = uspi->s_fsize - offset;
776		size -= rest;
777		cp = ubh->bh[begin]->b_data + offset;
778		while ((table[*cp++] & mask) == 0 && --rest)
779			;
780		if (rest || !size)
781			break;
782		begin++;
783		offset = 0;
784	}
785	return (size + rest);
786}
787
788/*
789 * Find a block of the specified size in the specified cylinder group.
790 * @sp: pointer to super block
791 * @ucpi: pointer to cylinder group info
792 * @goal: near which block we want find new one
793 * @count: specified size
794 */
795static u64 ufs_bitmap_search(struct super_block *sb,
796			     struct ufs_cg_private_info *ucpi,
797			     u64 goal, unsigned count)
798{
799	/*
800	 * Bit patterns for identifying fragments in the block map
801	 * used as ((map & mask_arr) == want_arr)
802	 */
803	static const int mask_arr[9] = {
804		0x3, 0x7, 0xf, 0x1f, 0x3f, 0x7f, 0xff, 0x1ff, 0x3ff
805	};
806	static const int want_arr[9] = {
807		0x0, 0x2, 0x6, 0xe, 0x1e, 0x3e, 0x7e, 0xfe, 0x1fe
808	};
809	struct ufs_sb_private_info *uspi = UFS_SB(sb)->s_uspi;
810	unsigned start, length, loc;
811	unsigned pos, want, blockmap, mask, end;
812	u64 result;
813
814	UFSD("ENTER, cg %u, goal %llu, count %u\n", ucpi->c_cgx,
815	     (unsigned long long)goal, count);
816
817	if (goal)
818		start = ufs_dtogd(uspi, goal) >> 3;
819	else
820		start = ucpi->c_frotor >> 3;
821		
822	length = ((uspi->s_fpg + 7) >> 3) - start;
823	loc = ubh_scanc(uspi, UCPI_UBH(ucpi), ucpi->c_freeoff + start, length,
824		(uspi->s_fpb == 8) ? ufs_fragtable_8fpb : ufs_fragtable_other,
825		1 << (count - 1 + (uspi->s_fpb & 7))); 
826	if (loc == 0) {
827		length = start + 1;
828		loc = ubh_scanc(uspi, UCPI_UBH(ucpi), ucpi->c_freeoff, length,
829				(uspi->s_fpb == 8) ? ufs_fragtable_8fpb :
830				ufs_fragtable_other,
831				1 << (count - 1 + (uspi->s_fpb & 7)));
832		if (loc == 0) {
833			ufs_error(sb, "ufs_bitmap_search",
834				  "bitmap corrupted on cg %u, start %u,"
835				  " length %u, count %u, freeoff %u\n",
836				  ucpi->c_cgx, start, length, count,
837				  ucpi->c_freeoff);
838			return INVBLOCK;
839		}
840		start = 0;
841	}
842	result = (start + length - loc) << 3;
843	ucpi->c_frotor = result;
844
845	/*
846	 * found the byte in the map
847	 */
848
849	for (end = result + 8; result < end; result += uspi->s_fpb) {
850		blockmap = ubh_blkmap(UCPI_UBH(ucpi), ucpi->c_freeoff, result);
851		blockmap <<= 1;
852		mask = mask_arr[count];
853		want = want_arr[count];
854		for (pos = 0; pos <= uspi->s_fpb - count; pos++) {
855			if ((blockmap & mask) == want) {
856				UFSD("EXIT, result %llu\n",
857				     (unsigned long long)result);
858				return result + pos;
859 			}
860			mask <<= 1;
861			want <<= 1;
862 		}
863 	}
864
865	ufs_error(sb, "ufs_bitmap_search", "block not in map on cg %u\n",
866		  ucpi->c_cgx);
867	UFSD("EXIT (FAILED)\n");
868	return INVBLOCK;
869}
870
871static void ufs_clusteracct(struct super_block * sb,
872	struct ufs_cg_private_info * ucpi, unsigned blkno, int cnt)
873{
874	struct ufs_sb_private_info * uspi;
875	int i, start, end, forw, back;
876	
877	uspi = UFS_SB(sb)->s_uspi;
878	if (uspi->s_contigsumsize <= 0)
879		return;
880
881	if (cnt > 0)
882		ubh_setbit(UCPI_UBH(ucpi), ucpi->c_clusteroff, blkno);
883	else
884		ubh_clrbit(UCPI_UBH(ucpi), ucpi->c_clusteroff, blkno);
885
886	/*
887	 * Find the size of the cluster going forward.
888	 */
889	start = blkno + 1;
890	end = start + uspi->s_contigsumsize;
891	if ( end >= ucpi->c_nclusterblks)
892		end = ucpi->c_nclusterblks;
893	i = ubh_find_next_zero_bit (UCPI_UBH(ucpi), ucpi->c_clusteroff, end, start);
894	if (i > end)
895		i = end;
896	forw = i - start;
897	
898	/*
899	 * Find the size of the cluster going backward.
900	 */
901	start = blkno - 1;
902	end = start - uspi->s_contigsumsize;
903	if (end < 0 ) 
904		end = -1;
905	i = ubh_find_last_zero_bit (UCPI_UBH(ucpi), ucpi->c_clusteroff, start, end);
906	if ( i < end) 
907		i = end;
908	back = start - i;
909	
910	/*
911	 * Account for old cluster and the possibly new forward and
912	 * back clusters.
913	 */
914	i = back + forw + 1;
915	if (i > uspi->s_contigsumsize)
916		i = uspi->s_contigsumsize;
917	fs32_add(sb, (__fs32*)ubh_get_addr(UCPI_UBH(ucpi), ucpi->c_clustersumoff + (i << 2)), cnt);
918	if (back > 0)
919		fs32_sub(sb, (__fs32*)ubh_get_addr(UCPI_UBH(ucpi), ucpi->c_clustersumoff + (back << 2)), cnt);
920	if (forw > 0)
921		fs32_sub(sb, (__fs32*)ubh_get_addr(UCPI_UBH(ucpi), ucpi->c_clustersumoff + (forw << 2)), cnt);
922}
923
924
925static unsigned char ufs_fragtable_8fpb[] = {
926	0x00, 0x01, 0x01, 0x02, 0x01, 0x01, 0x02, 0x04, 0x01, 0x01, 0x01, 0x03, 0x02, 0x03, 0x04, 0x08,
927	0x01, 0x01, 0x01, 0x03, 0x01, 0x01, 0x03, 0x05, 0x02, 0x03, 0x03, 0x02, 0x04, 0x05, 0x08, 0x10,
928	0x01, 0x01, 0x01, 0x03, 0x01, 0x01, 0x03, 0x05, 0x01, 0x01, 0x01, 0x03, 0x03, 0x03, 0x05, 0x09,
929	0x02, 0x03, 0x03, 0x02, 0x03, 0x03, 0x02, 0x06, 0x04, 0x05, 0x05, 0x06, 0x08, 0x09, 0x10, 0x20,
930	0x01, 0x01, 0x01, 0x03, 0x01, 0x01, 0x03, 0x05, 0x01, 0x01, 0x01, 0x03, 0x03, 0x03, 0x05, 0x09,	
931	0x01, 0x01, 0x01, 0x03, 0x01, 0x01, 0x03, 0x05, 0x03, 0x03, 0x03, 0x03, 0x05, 0x05, 0x09, 0x11,
932	0x02, 0x03, 0x03, 0x02, 0x03, 0x03, 0x02, 0x06, 0x03, 0x03, 0x03, 0x03, 0x02, 0x03, 0x06, 0x0A,
933	0x04, 0x05, 0x05, 0x06, 0x05, 0x05, 0x06, 0x04, 0x08, 0x09, 0x09, 0x0A, 0x10, 0x11, 0x20, 0x40,
934	0x01, 0x01, 0x01, 0x03, 0x01, 0x01, 0x03, 0x05, 0x01, 0x01, 0x01, 0x03, 0x03, 0x03, 0x05, 0x09,
935	0x01, 0x01, 0x01, 0x03, 0x01, 0x01, 0x03, 0x05, 0x03, 0x03, 0x03, 0x03, 0x05, 0x05, 0x09, 0x11,
936	0x01, 0x01, 0x01, 0x03, 0x01, 0x01, 0x03, 0x05, 0x01, 0x01, 0x01, 0x03, 0x03, 0x03, 0x05, 0x09,
937	0x03, 0x03, 0x03, 0x03, 0x03, 0x03, 0x03, 0x07, 0x05, 0x05, 0x05, 0x07, 0x09, 0x09, 0x11, 0x21,
938	0x02, 0x03, 0x03, 0x02, 0x03, 0x03, 0x02, 0x06, 0x03, 0x03, 0x03, 0x03, 0x02, 0x03, 0x06, 0x0A,
939	0x03, 0x03, 0x03, 0x03, 0x03, 0x03, 0x03, 0x07, 0x02, 0x03, 0x03, 0x02, 0x06, 0x07, 0x0A, 0x12,
940	0x04, 0x05, 0x05, 0x06, 0x05, 0x05, 0x06, 0x04, 0x05, 0x05, 0x05, 0x07, 0x06, 0x07, 0x04, 0x0C,
941	0x08, 0x09, 0x09, 0x0A, 0x09, 0x09, 0x0A, 0x0C, 0x10, 0x11, 0x11, 0x12, 0x20, 0x21, 0x40, 0x80,
942};
943
944static unsigned char ufs_fragtable_other[] = {
945	0x00, 0x16, 0x16, 0x2A, 0x16, 0x16, 0x26, 0x4E, 0x16, 0x16, 0x16, 0x3E, 0x2A, 0x3E, 0x4E, 0x8A,
946	0x16, 0x16, 0x16, 0x3E, 0x16, 0x16, 0x36, 0x5E, 0x16, 0x16, 0x16, 0x3E, 0x3E, 0x3E, 0x5E, 0x9E,
947	0x16, 0x16, 0x16, 0x3E, 0x16, 0x16, 0x36, 0x5E, 0x16, 0x16, 0x16, 0x3E, 0x3E, 0x3E, 0x5E, 0x9E,
948	0x2A, 0x3E, 0x3E, 0x2A, 0x3E, 0x3E, 0x2E, 0x6E, 0x3E, 0x3E, 0x3E, 0x3E, 0x2A, 0x3E, 0x6E, 0xAA,
949	0x16, 0x16, 0x16, 0x3E, 0x16, 0x16, 0x36, 0x5E, 0x16, 0x16, 0x16, 0x3E, 0x3E, 0x3E, 0x5E, 0x9E,
950	0x16, 0x16, 0x16, 0x3E, 0x16, 0x16, 0x36, 0x5E, 0x16, 0x16, 0x16, 0x3E, 0x3E, 0x3E, 0x5E, 0x9E,
951	0x26, 0x36, 0x36, 0x2E, 0x36, 0x36, 0x26, 0x6E, 0x36, 0x36, 0x36, 0x3E, 0x2E, 0x3E, 0x6E, 0xAE,
952	0x4E, 0x5E, 0x5E, 0x6E, 0x5E, 0x5E, 0x6E, 0x4E, 0x5E, 0x5E, 0x5E, 0x7E, 0x6E, 0x7E, 0x4E, 0xCE,
953	0x16, 0x16, 0x16, 0x3E, 0x16, 0x16, 0x36, 0x5E, 0x16, 0x16, 0x16, 0x3E, 0x3E, 0x3E, 0x5E, 0x9E,
954	0x16, 0x16, 0x16, 0x3E, 0x16, 0x16, 0x36, 0x5E, 0x16, 0x16, 0x16, 0x3E, 0x3E, 0x3E, 0x5E, 0x9E,
955	0x16, 0x16, 0x16, 0x3E, 0x16, 0x16, 0x36, 0x5E, 0x16, 0x16, 0x16, 0x3E, 0x3E, 0x3E, 0x5E, 0x9E,
956	0x3E, 0x3E, 0x3E, 0x3E, 0x3E, 0x3E, 0x3E, 0x7E, 0x3E, 0x3E, 0x3E, 0x3E, 0x3E, 0x3E, 0x7E, 0xBE,
957	0x2A, 0x3E, 0x3E, 0x2A, 0x3E, 0x3E, 0x2E, 0x6E, 0x3E, 0x3E, 0x3E, 0x3E, 0x2A, 0x3E, 0x6E, 0xAA,
958	0x3E, 0x3E, 0x3E, 0x3E, 0x3E, 0x3E, 0x3E, 0x7E,	0x3E, 0x3E, 0x3E, 0x3E, 0x3E, 0x3E, 0x7E, 0xBE,
959	0x4E, 0x5E, 0x5E, 0x6E, 0x5E, 0x5E, 0x6E, 0x4E, 0x5E, 0x5E, 0x5E, 0x7E, 0x6E, 0x7E, 0x4E, 0xCE,
960	0x8A, 0x9E, 0x9E, 0xAA, 0x9E, 0x9E, 0xAE, 0xCE, 0x9E, 0x9E, 0x9E, 0xBE, 0xAA, 0xBE, 0xCE, 0x8A,
961};
  1/*
  2 *  linux/fs/ufs/balloc.c
  3 *
  4 * Copyright (C) 1998
  5 * Daniel Pirkl <daniel.pirkl@email.cz>
  6 * Charles University, Faculty of Mathematics and Physics
  7 *
  8 * UFS2 write support Evgeniy Dushistov <dushistov@mail.ru>, 2007
  9 */
 10
 11#include <linux/fs.h>
 12#include <linux/stat.h>
 13#include <linux/time.h>
 14#include <linux/string.h>
 15#include <linux/buffer_head.h>
 16#include <linux/capability.h>
 17#include <linux/bitops.h>
 18#include <asm/byteorder.h>
 19
 20#include "ufs_fs.h"
 21#include "ufs.h"
 22#include "swab.h"
 23#include "util.h"
 24
 25#define INVBLOCK ((u64)-1L)
 26
 27static u64 ufs_add_fragments(struct inode *, u64, unsigned, unsigned, int *);
 28static u64 ufs_alloc_fragments(struct inode *, unsigned, u64, unsigned, int *);
 29static u64 ufs_alloccg_block(struct inode *, struct ufs_cg_private_info *, u64, int *);
 30static u64 ufs_bitmap_search (struct super_block *, struct ufs_cg_private_info *, u64, unsigned);
 31static unsigned char ufs_fragtable_8fpb[], ufs_fragtable_other[];
 32static void ufs_clusteracct(struct super_block *, struct ufs_cg_private_info *, unsigned, int);
 33
 34/*
 35 * Free 'count' fragments from fragment number 'fragment'
 36 */
 37void ufs_free_fragments(struct inode *inode, u64 fragment, unsigned count)
 38{
 39	struct super_block * sb;
 40	struct ufs_sb_private_info * uspi;
 41	struct ufs_cg_private_info * ucpi;
 42	struct ufs_cylinder_group * ucg;
 43	unsigned cgno, bit, end_bit, bbase, blkmap, i;
 44	u64 blkno;
 45	
 46	sb = inode->i_sb;
 47	uspi = UFS_SB(sb)->s_uspi;
 48	
 49	UFSD("ENTER, fragment %llu, count %u\n",
 50	     (unsigned long long)fragment, count);
 51	
 52	if (ufs_fragnum(fragment) + count > uspi->s_fpg)
 53		ufs_error (sb, "ufs_free_fragments", "internal error");
 54	
 55	mutex_lock(&UFS_SB(sb)->s_lock);
 56	
 57	cgno = ufs_dtog(uspi, fragment);
 58	bit = ufs_dtogd(uspi, fragment);
 59	if (cgno >= uspi->s_ncg) {
 60		ufs_panic (sb, "ufs_free_fragments", "freeing blocks are outside device");
 61		goto failed;
 62	}
 63		
 64	ucpi = ufs_load_cylinder (sb, cgno);
 65	if (!ucpi) 
 66		goto failed;
 67	ucg = ubh_get_ucg (UCPI_UBH(ucpi));
 68	if (!ufs_cg_chkmagic(sb, ucg)) {
 69		ufs_panic (sb, "ufs_free_fragments", "internal error, bad magic number on cg %u", cgno);
 70		goto failed;
 71	}
 72
 73	end_bit = bit + count;
 74	bbase = ufs_blknum (bit);
 75	blkmap = ubh_blkmap (UCPI_UBH(ucpi), ucpi->c_freeoff, bbase);
 76	ufs_fragacct (sb, blkmap, ucg->cg_frsum, -1);
 77	for (i = bit; i < end_bit; i++) {
 78		if (ubh_isclr (UCPI_UBH(ucpi), ucpi->c_freeoff, i))
 79			ubh_setbit (UCPI_UBH(ucpi), ucpi->c_freeoff, i);
 80		else 
 81			ufs_error (sb, "ufs_free_fragments",
 82				   "bit already cleared for fragment %u", i);
 83	}
 84	
 85	fs32_add(sb, &ucg->cg_cs.cs_nffree, count);
 86	uspi->cs_total.cs_nffree += count;
 87	fs32_add(sb, &UFS_SB(sb)->fs_cs(cgno).cs_nffree, count);
 88	blkmap = ubh_blkmap (UCPI_UBH(ucpi), ucpi->c_freeoff, bbase);
 89	ufs_fragacct(sb, blkmap, ucg->cg_frsum, 1);
 90
 91	/*
 92	 * Trying to reassemble free fragments into block
 93	 */
 94	blkno = ufs_fragstoblks (bbase);
 95	if (ubh_isblockset(UCPI_UBH(ucpi), ucpi->c_freeoff, blkno)) {
 96		fs32_sub(sb, &ucg->cg_cs.cs_nffree, uspi->s_fpb);
 97		uspi->cs_total.cs_nffree -= uspi->s_fpb;
 98		fs32_sub(sb, &UFS_SB(sb)->fs_cs(cgno).cs_nffree, uspi->s_fpb);
 99		if ((UFS_SB(sb)->s_flags & UFS_CG_MASK) == UFS_CG_44BSD)
100			ufs_clusteracct (sb, ucpi, blkno, 1);
101		fs32_add(sb, &ucg->cg_cs.cs_nbfree, 1);
102		uspi->cs_total.cs_nbfree++;
103		fs32_add(sb, &UFS_SB(sb)->fs_cs(cgno).cs_nbfree, 1);
104		if (uspi->fs_magic != UFS2_MAGIC) {
105			unsigned cylno = ufs_cbtocylno (bbase);
106
107			fs16_add(sb, &ubh_cg_blks(ucpi, cylno,
108						  ufs_cbtorpos(bbase)), 1);
109			fs32_add(sb, &ubh_cg_blktot(ucpi, cylno), 1);
110		}
111	}
112	
113	ubh_mark_buffer_dirty (USPI_UBH(uspi));
114	ubh_mark_buffer_dirty (UCPI_UBH(ucpi));
115	if (sb->s_flags & MS_SYNCHRONOUS)
116		ubh_sync_block(UCPI_UBH(ucpi));
117	ufs_mark_sb_dirty(sb);
118	
119	mutex_unlock(&UFS_SB(sb)->s_lock);
120	UFSD("EXIT\n");
121	return;
122
123failed:
124	mutex_unlock(&UFS_SB(sb)->s_lock);
125	UFSD("EXIT (FAILED)\n");
126	return;
127}
128
129/*
130 * Free 'count' fragments from fragment number 'fragment' (free whole blocks)
131 */
132void ufs_free_blocks(struct inode *inode, u64 fragment, unsigned count)
133{
134	struct super_block * sb;
135	struct ufs_sb_private_info * uspi;
136	struct ufs_cg_private_info * ucpi;
137	struct ufs_cylinder_group * ucg;
138	unsigned overflow, cgno, bit, end_bit, i;
139	u64 blkno;
140	
141	sb = inode->i_sb;
142	uspi = UFS_SB(sb)->s_uspi;
143
144	UFSD("ENTER, fragment %llu, count %u\n",
145	     (unsigned long long)fragment, count);
146	
147	if ((fragment & uspi->s_fpbmask) || (count & uspi->s_fpbmask)) {
148		ufs_error (sb, "ufs_free_blocks", "internal error, "
149			   "fragment %llu, count %u\n",
150			   (unsigned long long)fragment, count);
151		goto failed;
152	}
153
154	mutex_lock(&UFS_SB(sb)->s_lock);
155	
156do_more:
157	overflow = 0;
158	cgno = ufs_dtog(uspi, fragment);
159	bit = ufs_dtogd(uspi, fragment);
160	if (cgno >= uspi->s_ncg) {
161		ufs_panic (sb, "ufs_free_blocks", "freeing blocks are outside device");
162		goto failed_unlock;
163	}
164	end_bit = bit + count;
165	if (end_bit > uspi->s_fpg) {
166		overflow = bit + count - uspi->s_fpg;
167		count -= overflow;
168		end_bit -= overflow;
169	}
170
171	ucpi = ufs_load_cylinder (sb, cgno);
172	if (!ucpi) 
173		goto failed_unlock;
174	ucg = ubh_get_ucg (UCPI_UBH(ucpi));
175	if (!ufs_cg_chkmagic(sb, ucg)) {
176		ufs_panic (sb, "ufs_free_blocks", "internal error, bad magic number on cg %u", cgno);
177		goto failed_unlock;
178	}
179
180	for (i = bit; i < end_bit; i += uspi->s_fpb) {
181		blkno = ufs_fragstoblks(i);
182		if (ubh_isblockset(UCPI_UBH(ucpi), ucpi->c_freeoff, blkno)) {
183			ufs_error(sb, "ufs_free_blocks", "freeing free fragment");
184		}
185		ubh_setblock(UCPI_UBH(ucpi), ucpi->c_freeoff, blkno);
186		if ((UFS_SB(sb)->s_flags & UFS_CG_MASK) == UFS_CG_44BSD)
187			ufs_clusteracct (sb, ucpi, blkno, 1);
188
189		fs32_add(sb, &ucg->cg_cs.cs_nbfree, 1);
190		uspi->cs_total.cs_nbfree++;
191		fs32_add(sb, &UFS_SB(sb)->fs_cs(cgno).cs_nbfree, 1);
192
193		if (uspi->fs_magic != UFS2_MAGIC) {
194			unsigned cylno = ufs_cbtocylno(i);
195
196			fs16_add(sb, &ubh_cg_blks(ucpi, cylno,
197						  ufs_cbtorpos(i)), 1);
198			fs32_add(sb, &ubh_cg_blktot(ucpi, cylno), 1);
199		}
200	}
201
202	ubh_mark_buffer_dirty (USPI_UBH(uspi));
203	ubh_mark_buffer_dirty (UCPI_UBH(ucpi));
204	if (sb->s_flags & MS_SYNCHRONOUS)
205		ubh_sync_block(UCPI_UBH(ucpi));
206
207	if (overflow) {
208		fragment += count;
209		count = overflow;
210		goto do_more;
211	}
212
213	ufs_mark_sb_dirty(sb);
214	mutex_unlock(&UFS_SB(sb)->s_lock);
215	UFSD("EXIT\n");
216	return;
217
218failed_unlock:
219	mutex_unlock(&UFS_SB(sb)->s_lock);
220failed:
221	UFSD("EXIT (FAILED)\n");
222	return;
223}
224
225/*
226 * Modify inode page cache in such way:
227 * have - blocks with b_blocknr equal to oldb...oldb+count-1
228 * get - blocks with b_blocknr equal to newb...newb+count-1
229 * also we suppose that oldb...oldb+count-1 blocks
230 * situated at the end of file.
231 *
232 * We can come here from ufs_writepage or ufs_prepare_write,
233 * locked_page is argument of these functions, so we already lock it.
234 */
235static void ufs_change_blocknr(struct inode *inode, sector_t beg,
236			       unsigned int count, sector_t oldb,
237			       sector_t newb, struct page *locked_page)
238{
239	const unsigned blks_per_page =
240		1 << (PAGE_CACHE_SHIFT - inode->i_blkbits);
241	const unsigned mask = blks_per_page - 1;
242	struct address_space * const mapping = inode->i_mapping;
243	pgoff_t index, cur_index, last_index;
244	unsigned pos, j, lblock;
245	sector_t end, i;
246	struct page *page;
247	struct buffer_head *head, *bh;
248
249	UFSD("ENTER, ino %lu, count %u, oldb %llu, newb %llu\n",
250	      inode->i_ino, count,
251	     (unsigned long long)oldb, (unsigned long long)newb);
252
253	BUG_ON(!locked_page);
254	BUG_ON(!PageLocked(locked_page));
255
256	cur_index = locked_page->index;
257	end = count + beg;
258	last_index = end >> (PAGE_CACHE_SHIFT - inode->i_blkbits);
259	for (i = beg; i < end; i = (i | mask) + 1) {
260		index = i >> (PAGE_CACHE_SHIFT - inode->i_blkbits);
261
262		if (likely(cur_index != index)) {
263			page = ufs_get_locked_page(mapping, index);
264			if (!page)/* it was truncated */
265				continue;
266			if (IS_ERR(page)) {/* or EIO */
267				ufs_error(inode->i_sb, __func__,
268					  "read of page %llu failed\n",
269					  (unsigned long long)index);
270				continue;
271			}
272		} else
273			page = locked_page;
274
275		head = page_buffers(page);
276		bh = head;
277		pos = i & mask;
278		for (j = 0; j < pos; ++j)
279			bh = bh->b_this_page;
280
281
282		if (unlikely(index == last_index))
283			lblock = end & mask;
284		else
285			lblock = blks_per_page;
286
287		do {
288			if (j >= lblock)
289				break;
290			pos = (i - beg) + j;
291
292			if (!buffer_mapped(bh))
293					map_bh(bh, inode->i_sb, oldb + pos);
294			if (!buffer_uptodate(bh)) {
295				ll_rw_block(READ, 1, &bh);
296				wait_on_buffer(bh);
297				if (!buffer_uptodate(bh)) {
298					ufs_error(inode->i_sb, __func__,
299						  "read of block failed\n");
300					break;
301				}
302			}
303
304			UFSD(" change from %llu to %llu, pos %u\n",
305			     (unsigned long long)(pos + oldb),
306			     (unsigned long long)(pos + newb), pos);
307
308			bh->b_blocknr = newb + pos;
309			unmap_underlying_metadata(bh->b_bdev,
310						  bh->b_blocknr);
311			mark_buffer_dirty(bh);
312			++j;
313			bh = bh->b_this_page;
314		} while (bh != head);
315
316		if (likely(cur_index != index))
317			ufs_put_locked_page(page);
318 	}
319	UFSD("EXIT\n");
320}
321
322static void ufs_clear_frags(struct inode *inode, sector_t beg, unsigned int n,
323			    int sync)
324{
325	struct buffer_head *bh;
326	sector_t end = beg + n;
327
328	for (; beg < end; ++beg) {
329		bh = sb_getblk(inode->i_sb, beg);
330		lock_buffer(bh);
331		memset(bh->b_data, 0, inode->i_sb->s_blocksize);
332		set_buffer_uptodate(bh);
333		mark_buffer_dirty(bh);
334		unlock_buffer(bh);
335		if (IS_SYNC(inode) || sync)
336			sync_dirty_buffer(bh);
337		brelse(bh);
338	}
339}
340
341u64 ufs_new_fragments(struct inode *inode, void *p, u64 fragment,
342			   u64 goal, unsigned count, int *err,
343			   struct page *locked_page)
344{
345	struct super_block * sb;
346	struct ufs_sb_private_info * uspi;
347	struct ufs_super_block_first * usb1;
348	unsigned cgno, oldcount, newcount;
349	u64 tmp, request, result;
350	
351	UFSD("ENTER, ino %lu, fragment %llu, goal %llu, count %u\n",
352	     inode->i_ino, (unsigned long long)fragment,
353	     (unsigned long long)goal, count);
354	
355	sb = inode->i_sb;
356	uspi = UFS_SB(sb)->s_uspi;
357	usb1 = ubh_get_usb_first(uspi);
358	*err = -ENOSPC;
359
360	mutex_lock(&UFS_SB(sb)->s_lock);
361	tmp = ufs_data_ptr_to_cpu(sb, p);
362
363	if (count + ufs_fragnum(fragment) > uspi->s_fpb) {
364		ufs_warning(sb, "ufs_new_fragments", "internal warning"
365			    " fragment %llu, count %u",
366			    (unsigned long long)fragment, count);
367		count = uspi->s_fpb - ufs_fragnum(fragment); 
368	}
369	oldcount = ufs_fragnum (fragment);
370	newcount = oldcount + count;
371
372	/*
373	 * Somebody else has just allocated our fragments
374	 */
375	if (oldcount) {
376		if (!tmp) {
377			ufs_error(sb, "ufs_new_fragments", "internal error, "
378				  "fragment %llu, tmp %llu\n",
379				  (unsigned long long)fragment,
380				  (unsigned long long)tmp);
381			mutex_unlock(&UFS_SB(sb)->s_lock);
382			return INVBLOCK;
383		}
384		if (fragment < UFS_I(inode)->i_lastfrag) {
385			UFSD("EXIT (ALREADY ALLOCATED)\n");
386			mutex_unlock(&UFS_SB(sb)->s_lock);
387			return 0;
388		}
389	}
390	else {
391		if (tmp) {
392			UFSD("EXIT (ALREADY ALLOCATED)\n");
393			mutex_unlock(&UFS_SB(sb)->s_lock);
394			return 0;
395		}
396	}
397
398	/*
399	 * There is not enough space for user on the device
400	 */
401	if (!capable(CAP_SYS_RESOURCE) && ufs_freespace(uspi, UFS_MINFREE) <= 0) {
402		mutex_unlock(&UFS_SB(sb)->s_lock);
403		UFSD("EXIT (FAILED)\n");
404		return 0;
405	}
406
407	if (goal >= uspi->s_size) 
408		goal = 0;
409	if (goal == 0) 
410		cgno = ufs_inotocg (inode->i_ino);
411	else
412		cgno = ufs_dtog(uspi, goal);
413	 
414	/*
415	 * allocate new fragment
416	 */
417	if (oldcount == 0) {
418		result = ufs_alloc_fragments (inode, cgno, goal, count, err);
419		if (result) {
420			ufs_cpu_to_data_ptr(sb, p, result);
421			*err = 0;
422			UFS_I(inode)->i_lastfrag =
423				max(UFS_I(inode)->i_lastfrag, fragment + count);
424			ufs_clear_frags(inode, result + oldcount,
425					newcount - oldcount, locked_page != NULL);
426		}
427		mutex_unlock(&UFS_SB(sb)->s_lock);
428		UFSD("EXIT, result %llu\n", (unsigned long long)result);
429		return result;
430	}
431
432	/*
433	 * resize block
434	 */
435	result = ufs_add_fragments (inode, tmp, oldcount, newcount, err);
436	if (result) {
437		*err = 0;
438		UFS_I(inode)->i_lastfrag = max(UFS_I(inode)->i_lastfrag,
439						fragment + count);
440		ufs_clear_frags(inode, result + oldcount, newcount - oldcount,
441				locked_page != NULL);
442		mutex_unlock(&UFS_SB(sb)->s_lock);
443		UFSD("EXIT, result %llu\n", (unsigned long long)result);
444		return result;
445	}
446
447	/*
448	 * allocate new block and move data
449	 */
450	switch (fs32_to_cpu(sb, usb1->fs_optim)) {
451	    case UFS_OPTSPACE:
452		request = newcount;
453		if (uspi->s_minfree < 5 || uspi->cs_total.cs_nffree
454		    > uspi->s_dsize * uspi->s_minfree / (2 * 100))
455			break;
456		usb1->fs_optim = cpu_to_fs32(sb, UFS_OPTTIME);
457		break;
458	    default:
459		usb1->fs_optim = cpu_to_fs32(sb, UFS_OPTTIME);
460	
461	    case UFS_OPTTIME:
462		request = uspi->s_fpb;
463		if (uspi->cs_total.cs_nffree < uspi->s_dsize *
464		    (uspi->s_minfree - 2) / 100)
465			break;
466		usb1->fs_optim = cpu_to_fs32(sb, UFS_OPTTIME);
467		break;
468	}
469	result = ufs_alloc_fragments (inode, cgno, goal, request, err);
470	if (result) {
471		ufs_clear_frags(inode, result + oldcount, newcount - oldcount,
472				locked_page != NULL);
473		ufs_change_blocknr(inode, fragment - oldcount, oldcount,
474				   uspi->s_sbbase + tmp,
475				   uspi->s_sbbase + result, locked_page);
476		ufs_cpu_to_data_ptr(sb, p, result);
477		*err = 0;
478		UFS_I(inode)->i_lastfrag = max(UFS_I(inode)->i_lastfrag,
479						fragment + count);
480		mutex_unlock(&UFS_SB(sb)->s_lock);
481		if (newcount < request)
482			ufs_free_fragments (inode, result + newcount, request - newcount);
483		ufs_free_fragments (inode, tmp, oldcount);
484		UFSD("EXIT, result %llu\n", (unsigned long long)result);
485		return result;
486	}
487
488	mutex_unlock(&UFS_SB(sb)->s_lock);
489	UFSD("EXIT (FAILED)\n");
490	return 0;
491}		
492
493static u64 ufs_add_fragments(struct inode *inode, u64 fragment,
494			     unsigned oldcount, unsigned newcount, int *err)
495{
496	struct super_block * sb;
497	struct ufs_sb_private_info * uspi;
498	struct ufs_cg_private_info * ucpi;
499	struct ufs_cylinder_group * ucg;
500	unsigned cgno, fragno, fragoff, count, fragsize, i;
501	
502	UFSD("ENTER, fragment %llu, oldcount %u, newcount %u\n",
503	     (unsigned long long)fragment, oldcount, newcount);
504	
505	sb = inode->i_sb;
506	uspi = UFS_SB(sb)->s_uspi;
507	count = newcount - oldcount;
508	
509	cgno = ufs_dtog(uspi, fragment);
510	if (fs32_to_cpu(sb, UFS_SB(sb)->fs_cs(cgno).cs_nffree) < count)
511		return 0;
512	if ((ufs_fragnum (fragment) + newcount) > uspi->s_fpb)
513		return 0;
514	ucpi = ufs_load_cylinder (sb, cgno);
515	if (!ucpi)
516		return 0;
517	ucg = ubh_get_ucg (UCPI_UBH(ucpi));
518	if (!ufs_cg_chkmagic(sb, ucg)) {
519		ufs_panic (sb, "ufs_add_fragments",
520			"internal error, bad magic number on cg %u", cgno);
521		return 0;
522	}
523
524	fragno = ufs_dtogd(uspi, fragment);
525	fragoff = ufs_fragnum (fragno);
526	for (i = oldcount; i < newcount; i++)
527		if (ubh_isclr (UCPI_UBH(ucpi), ucpi->c_freeoff, fragno + i))
528			return 0;
529	/*
530	 * Block can be extended
531	 */
532	ucg->cg_time = cpu_to_fs32(sb, get_seconds());
533	for (i = newcount; i < (uspi->s_fpb - fragoff); i++)
534		if (ubh_isclr (UCPI_UBH(ucpi), ucpi->c_freeoff, fragno + i))
535			break;
536	fragsize = i - oldcount;
537	if (!fs32_to_cpu(sb, ucg->cg_frsum[fragsize]))
538		ufs_panic (sb, "ufs_add_fragments",
539			"internal error or corrupted bitmap on cg %u", cgno);
540	fs32_sub(sb, &ucg->cg_frsum[fragsize], 1);
541	if (fragsize != count)
542		fs32_add(sb, &ucg->cg_frsum[fragsize - count], 1);
543	for (i = oldcount; i < newcount; i++)
544		ubh_clrbit (UCPI_UBH(ucpi), ucpi->c_freeoff, fragno + i);
545
546	fs32_sub(sb, &ucg->cg_cs.cs_nffree, count);
547	fs32_sub(sb, &UFS_SB(sb)->fs_cs(cgno).cs_nffree, count);
548	uspi->cs_total.cs_nffree -= count;
549	
550	ubh_mark_buffer_dirty (USPI_UBH(uspi));
551	ubh_mark_buffer_dirty (UCPI_UBH(ucpi));
552	if (sb->s_flags & MS_SYNCHRONOUS)
553		ubh_sync_block(UCPI_UBH(ucpi));
554	ufs_mark_sb_dirty(sb);
555
556	UFSD("EXIT, fragment %llu\n", (unsigned long long)fragment);
557	
558	return fragment;
559}
560
561#define UFS_TEST_FREE_SPACE_CG \
562	ucg = (struct ufs_cylinder_group *) UFS_SB(sb)->s_ucg[cgno]->b_data; \
563	if (fs32_to_cpu(sb, ucg->cg_cs.cs_nbfree)) \
564		goto cg_found; \
565	for (k = count; k < uspi->s_fpb; k++) \
566		if (fs32_to_cpu(sb, ucg->cg_frsum[k])) \
567			goto cg_found; 
568
569static u64 ufs_alloc_fragments(struct inode *inode, unsigned cgno,
570			       u64 goal, unsigned count, int *err)
571{
572	struct super_block * sb;
573	struct ufs_sb_private_info * uspi;
574	struct ufs_cg_private_info * ucpi;
575	struct ufs_cylinder_group * ucg;
576	unsigned oldcg, i, j, k, allocsize;
577	u64 result;
578	
579	UFSD("ENTER, ino %lu, cgno %u, goal %llu, count %u\n",
580	     inode->i_ino, cgno, (unsigned long long)goal, count);
581
582	sb = inode->i_sb;
583	uspi = UFS_SB(sb)->s_uspi;
584	oldcg = cgno;
585	
586	/*
587	 * 1. searching on preferred cylinder group
588	 */
589	UFS_TEST_FREE_SPACE_CG
590
591	/*
592	 * 2. quadratic rehash
593	 */
594	for (j = 1; j < uspi->s_ncg; j *= 2) {
595		cgno += j;
596		if (cgno >= uspi->s_ncg) 
597			cgno -= uspi->s_ncg;
598		UFS_TEST_FREE_SPACE_CG
599	}
600
601	/*
602	 * 3. brute force search
603	 * We start at i = 2 ( 0 is checked at 1.step, 1 at 2.step )
604	 */
605	cgno = (oldcg + 1) % uspi->s_ncg;
606	for (j = 2; j < uspi->s_ncg; j++) {
607		cgno++;
608		if (cgno >= uspi->s_ncg)
609			cgno = 0;
610		UFS_TEST_FREE_SPACE_CG
611	}
612	
613	UFSD("EXIT (FAILED)\n");
614	return 0;
615
616cg_found:
617	ucpi = ufs_load_cylinder (sb, cgno);
618	if (!ucpi)
619		return 0;
620	ucg = ubh_get_ucg (UCPI_UBH(ucpi));
621	if (!ufs_cg_chkmagic(sb, ucg)) 
622		ufs_panic (sb, "ufs_alloc_fragments",
623			"internal error, bad magic number on cg %u", cgno);
624	ucg->cg_time = cpu_to_fs32(sb, get_seconds());
625
626	if (count == uspi->s_fpb) {
627		result = ufs_alloccg_block (inode, ucpi, goal, err);
628		if (result == INVBLOCK)
629			return 0;
630		goto succed;
631	}
632
633	for (allocsize = count; allocsize < uspi->s_fpb; allocsize++)
634		if (fs32_to_cpu(sb, ucg->cg_frsum[allocsize]) != 0)
635			break;
636	
637	if (allocsize == uspi->s_fpb) {
638		result = ufs_alloccg_block (inode, ucpi, goal, err);
639		if (result == INVBLOCK)
640			return 0;
641		goal = ufs_dtogd(uspi, result);
642		for (i = count; i < uspi->s_fpb; i++)
643			ubh_setbit (UCPI_UBH(ucpi), ucpi->c_freeoff, goal + i);
644		i = uspi->s_fpb - count;
645
646		fs32_add(sb, &ucg->cg_cs.cs_nffree, i);
647		uspi->cs_total.cs_nffree += i;
648		fs32_add(sb, &UFS_SB(sb)->fs_cs(cgno).cs_nffree, i);
649		fs32_add(sb, &ucg->cg_frsum[i], 1);
650		goto succed;
651	}
652
653	result = ufs_bitmap_search (sb, ucpi, goal, allocsize);
654	if (result == INVBLOCK)
655		return 0;
656	for (i = 0; i < count; i++)
657		ubh_clrbit (UCPI_UBH(ucpi), ucpi->c_freeoff, result + i);
658	
659	fs32_sub(sb, &ucg->cg_cs.cs_nffree, count);
660	uspi->cs_total.cs_nffree -= count;
661	fs32_sub(sb, &UFS_SB(sb)->fs_cs(cgno).cs_nffree, count);
662	fs32_sub(sb, &ucg->cg_frsum[allocsize], 1);
663
664	if (count != allocsize)
665		fs32_add(sb, &ucg->cg_frsum[allocsize - count], 1);
666
667succed:
668	ubh_mark_buffer_dirty (USPI_UBH(uspi));
669	ubh_mark_buffer_dirty (UCPI_UBH(ucpi));
670	if (sb->s_flags & MS_SYNCHRONOUS)
671		ubh_sync_block(UCPI_UBH(ucpi));
672	ufs_mark_sb_dirty(sb);
673
674	result += cgno * uspi->s_fpg;
675	UFSD("EXIT3, result %llu\n", (unsigned long long)result);
676	return result;
677}
678
679static u64 ufs_alloccg_block(struct inode *inode,
680			     struct ufs_cg_private_info *ucpi,
681			     u64 goal, int *err)
682{
683	struct super_block * sb;
684	struct ufs_sb_private_info * uspi;
685	struct ufs_cylinder_group * ucg;
686	u64 result, blkno;
687
688	UFSD("ENTER, goal %llu\n", (unsigned long long)goal);
689
690	sb = inode->i_sb;
691	uspi = UFS_SB(sb)->s_uspi;
692	ucg = ubh_get_ucg(UCPI_UBH(ucpi));
693
694	if (goal == 0) {
695		goal = ucpi->c_rotor;
696		goto norot;
697	}
698	goal = ufs_blknum (goal);
699	goal = ufs_dtogd(uspi, goal);
700	
701	/*
702	 * If the requested block is available, use it.
703	 */
704	if (ubh_isblockset(UCPI_UBH(ucpi), ucpi->c_freeoff, ufs_fragstoblks(goal))) {
705		result = goal;
706		goto gotit;
707	}
708	
709norot:	
710	result = ufs_bitmap_search (sb, ucpi, goal, uspi->s_fpb);
711	if (result == INVBLOCK)
712		return INVBLOCK;
713	ucpi->c_rotor = result;
714gotit:
715	blkno = ufs_fragstoblks(result);
716	ubh_clrblock (UCPI_UBH(ucpi), ucpi->c_freeoff, blkno);
717	if ((UFS_SB(sb)->s_flags & UFS_CG_MASK) == UFS_CG_44BSD)
718		ufs_clusteracct (sb, ucpi, blkno, -1);
719
720	fs32_sub(sb, &ucg->cg_cs.cs_nbfree, 1);
721	uspi->cs_total.cs_nbfree--;
722	fs32_sub(sb, &UFS_SB(sb)->fs_cs(ucpi->c_cgx).cs_nbfree, 1);
723
724	if (uspi->fs_magic != UFS2_MAGIC) {
725		unsigned cylno = ufs_cbtocylno((unsigned)result);
726
727		fs16_sub(sb, &ubh_cg_blks(ucpi, cylno,
728					  ufs_cbtorpos((unsigned)result)), 1);
729		fs32_sub(sb, &ubh_cg_blktot(ucpi, cylno), 1);
730	}
731	
732	UFSD("EXIT, result %llu\n", (unsigned long long)result);
733
734	return result;
735}
736
737static unsigned ubh_scanc(struct ufs_sb_private_info *uspi,
738			  struct ufs_buffer_head *ubh,
739			  unsigned begin, unsigned size,
740			  unsigned char *table, unsigned char mask)
741{
742	unsigned rest, offset;
743	unsigned char *cp;
744	
745
746	offset = begin & ~uspi->s_fmask;
747	begin >>= uspi->s_fshift;
748	for (;;) {
749		if ((offset + size) < uspi->s_fsize)
750			rest = size;
751		else
752			rest = uspi->s_fsize - offset;
753		size -= rest;
754		cp = ubh->bh[begin]->b_data + offset;
755		while ((table[*cp++] & mask) == 0 && --rest)
756			;
757		if (rest || !size)
758			break;
759		begin++;
760		offset = 0;
761	}
762	return (size + rest);
763}
764
765/*
766 * Find a block of the specified size in the specified cylinder group.
767 * @sp: pointer to super block
768 * @ucpi: pointer to cylinder group info
769 * @goal: near which block we want find new one
770 * @count: specified size
771 */
772static u64 ufs_bitmap_search(struct super_block *sb,
773			     struct ufs_cg_private_info *ucpi,
774			     u64 goal, unsigned count)
775{
776	/*
777	 * Bit patterns for identifying fragments in the block map
778	 * used as ((map & mask_arr) == want_arr)
779	 */
780	static const int mask_arr[9] = {
781		0x3, 0x7, 0xf, 0x1f, 0x3f, 0x7f, 0xff, 0x1ff, 0x3ff
782	};
783	static const int want_arr[9] = {
784		0x0, 0x2, 0x6, 0xe, 0x1e, 0x3e, 0x7e, 0xfe, 0x1fe
785	};
786	struct ufs_sb_private_info *uspi = UFS_SB(sb)->s_uspi;
787	struct ufs_cylinder_group *ucg;
788	unsigned start, length, loc;
789	unsigned pos, want, blockmap, mask, end;
790	u64 result;
791
792	UFSD("ENTER, cg %u, goal %llu, count %u\n", ucpi->c_cgx,
793	     (unsigned long long)goal, count);
794
795	ucg = ubh_get_ucg(UCPI_UBH(ucpi));
796
797	if (goal)
798		start = ufs_dtogd(uspi, goal) >> 3;
799	else
800		start = ucpi->c_frotor >> 3;
801		
802	length = ((uspi->s_fpg + 7) >> 3) - start;
803	loc = ubh_scanc(uspi, UCPI_UBH(ucpi), ucpi->c_freeoff + start, length,
804		(uspi->s_fpb == 8) ? ufs_fragtable_8fpb : ufs_fragtable_other,
805		1 << (count - 1 + (uspi->s_fpb & 7))); 
806	if (loc == 0) {
807		length = start + 1;
808		loc = ubh_scanc(uspi, UCPI_UBH(ucpi), ucpi->c_freeoff, length,
809				(uspi->s_fpb == 8) ? ufs_fragtable_8fpb :
810				ufs_fragtable_other,
811				1 << (count - 1 + (uspi->s_fpb & 7)));
812		if (loc == 0) {
813			ufs_error(sb, "ufs_bitmap_search",
814				  "bitmap corrupted on cg %u, start %u,"
815				  " length %u, count %u, freeoff %u\n",
816				  ucpi->c_cgx, start, length, count,
817				  ucpi->c_freeoff);
818			return INVBLOCK;
819		}
820		start = 0;
821	}
822	result = (start + length - loc) << 3;
823	ucpi->c_frotor = result;
824
825	/*
826	 * found the byte in the map
827	 */
828
829	for (end = result + 8; result < end; result += uspi->s_fpb) {
830		blockmap = ubh_blkmap(UCPI_UBH(ucpi), ucpi->c_freeoff, result);
831		blockmap <<= 1;
832		mask = mask_arr[count];
833		want = want_arr[count];
834		for (pos = 0; pos <= uspi->s_fpb - count; pos++) {
835			if ((blockmap & mask) == want) {
836				UFSD("EXIT, result %llu\n",
837				     (unsigned long long)result);
838				return result + pos;
839 			}
840			mask <<= 1;
841			want <<= 1;
842 		}
843 	}
844
845	ufs_error(sb, "ufs_bitmap_search", "block not in map on cg %u\n",
846		  ucpi->c_cgx);
847	UFSD("EXIT (FAILED)\n");
848	return INVBLOCK;
849}
850
851static void ufs_clusteracct(struct super_block * sb,
852	struct ufs_cg_private_info * ucpi, unsigned blkno, int cnt)
853{
854	struct ufs_sb_private_info * uspi;
855	int i, start, end, forw, back;
856	
857	uspi = UFS_SB(sb)->s_uspi;
858	if (uspi->s_contigsumsize <= 0)
859		return;
860
861	if (cnt > 0)
862		ubh_setbit(UCPI_UBH(ucpi), ucpi->c_clusteroff, blkno);
863	else
864		ubh_clrbit(UCPI_UBH(ucpi), ucpi->c_clusteroff, blkno);
865
866	/*
867	 * Find the size of the cluster going forward.
868	 */
869	start = blkno + 1;
870	end = start + uspi->s_contigsumsize;
871	if ( end >= ucpi->c_nclusterblks)
872		end = ucpi->c_nclusterblks;
873	i = ubh_find_next_zero_bit (UCPI_UBH(ucpi), ucpi->c_clusteroff, end, start);
874	if (i > end)
875		i = end;
876	forw = i - start;
877	
878	/*
879	 * Find the size of the cluster going backward.
880	 */
881	start = blkno - 1;
882	end = start - uspi->s_contigsumsize;
883	if (end < 0 ) 
884		end = -1;
885	i = ubh_find_last_zero_bit (UCPI_UBH(ucpi), ucpi->c_clusteroff, start, end);
886	if ( i < end) 
887		i = end;
888	back = start - i;
889	
890	/*
891	 * Account for old cluster and the possibly new forward and
892	 * back clusters.
893	 */
894	i = back + forw + 1;
895	if (i > uspi->s_contigsumsize)
896		i = uspi->s_contigsumsize;
897	fs32_add(sb, (__fs32*)ubh_get_addr(UCPI_UBH(ucpi), ucpi->c_clustersumoff + (i << 2)), cnt);
898	if (back > 0)
899		fs32_sub(sb, (__fs32*)ubh_get_addr(UCPI_UBH(ucpi), ucpi->c_clustersumoff + (back << 2)), cnt);
900	if (forw > 0)
901		fs32_sub(sb, (__fs32*)ubh_get_addr(UCPI_UBH(ucpi), ucpi->c_clustersumoff + (forw << 2)), cnt);
902}
903
904
905static unsigned char ufs_fragtable_8fpb[] = {
906	0x00, 0x01, 0x01, 0x02, 0x01, 0x01, 0x02, 0x04, 0x01, 0x01, 0x01, 0x03, 0x02, 0x03, 0x04, 0x08,
907	0x01, 0x01, 0x01, 0x03, 0x01, 0x01, 0x03, 0x05, 0x02, 0x03, 0x03, 0x02, 0x04, 0x05, 0x08, 0x10,
908	0x01, 0x01, 0x01, 0x03, 0x01, 0x01, 0x03, 0x05, 0x01, 0x01, 0x01, 0x03, 0x03, 0x03, 0x05, 0x09,
909	0x02, 0x03, 0x03, 0x02, 0x03, 0x03, 0x02, 0x06, 0x04, 0x05, 0x05, 0x06, 0x08, 0x09, 0x10, 0x20,
910	0x01, 0x01, 0x01, 0x03, 0x01, 0x01, 0x03, 0x05, 0x01, 0x01, 0x01, 0x03, 0x03, 0x03, 0x05, 0x09,	
911	0x01, 0x01, 0x01, 0x03, 0x01, 0x01, 0x03, 0x05, 0x03, 0x03, 0x03, 0x03, 0x05, 0x05, 0x09, 0x11,
912	0x02, 0x03, 0x03, 0x02, 0x03, 0x03, 0x02, 0x06, 0x03, 0x03, 0x03, 0x03, 0x02, 0x03, 0x06, 0x0A,
913	0x04, 0x05, 0x05, 0x06, 0x05, 0x05, 0x06, 0x04, 0x08, 0x09, 0x09, 0x0A, 0x10, 0x11, 0x20, 0x40,
914	0x01, 0x01, 0x01, 0x03, 0x01, 0x01, 0x03, 0x05, 0x01, 0x01, 0x01, 0x03, 0x03, 0x03, 0x05, 0x09,
915	0x01, 0x01, 0x01, 0x03, 0x01, 0x01, 0x03, 0x05, 0x03, 0x03, 0x03, 0x03, 0x05, 0x05, 0x09, 0x11,
916	0x01, 0x01, 0x01, 0x03, 0x01, 0x01, 0x03, 0x05, 0x01, 0x01, 0x01, 0x03, 0x03, 0x03, 0x05, 0x09,
917	0x03, 0x03, 0x03, 0x03, 0x03, 0x03, 0x03, 0x07, 0x05, 0x05, 0x05, 0x07, 0x09, 0x09, 0x11, 0x21,
918	0x02, 0x03, 0x03, 0x02, 0x03, 0x03, 0x02, 0x06, 0x03, 0x03, 0x03, 0x03, 0x02, 0x03, 0x06, 0x0A,
919	0x03, 0x03, 0x03, 0x03, 0x03, 0x03, 0x03, 0x07, 0x02, 0x03, 0x03, 0x02, 0x06, 0x07, 0x0A, 0x12,
920	0x04, 0x05, 0x05, 0x06, 0x05, 0x05, 0x06, 0x04, 0x05, 0x05, 0x05, 0x07, 0x06, 0x07, 0x04, 0x0C,
921	0x08, 0x09, 0x09, 0x0A, 0x09, 0x09, 0x0A, 0x0C, 0x10, 0x11, 0x11, 0x12, 0x20, 0x21, 0x40, 0x80,
922};
923
924static unsigned char ufs_fragtable_other[] = {
925	0x00, 0x16, 0x16, 0x2A, 0x16, 0x16, 0x26, 0x4E, 0x16, 0x16, 0x16, 0x3E, 0x2A, 0x3E, 0x4E, 0x8A,
926	0x16, 0x16, 0x16, 0x3E, 0x16, 0x16, 0x36, 0x5E, 0x16, 0x16, 0x16, 0x3E, 0x3E, 0x3E, 0x5E, 0x9E,
927	0x16, 0x16, 0x16, 0x3E, 0x16, 0x16, 0x36, 0x5E, 0x16, 0x16, 0x16, 0x3E, 0x3E, 0x3E, 0x5E, 0x9E,
928	0x2A, 0x3E, 0x3E, 0x2A, 0x3E, 0x3E, 0x2E, 0x6E, 0x3E, 0x3E, 0x3E, 0x3E, 0x2A, 0x3E, 0x6E, 0xAA,
929	0x16, 0x16, 0x16, 0x3E, 0x16, 0x16, 0x36, 0x5E, 0x16, 0x16, 0x16, 0x3E, 0x3E, 0x3E, 0x5E, 0x9E,
930	0x16, 0x16, 0x16, 0x3E, 0x16, 0x16, 0x36, 0x5E, 0x16, 0x16, 0x16, 0x3E, 0x3E, 0x3E, 0x5E, 0x9E,
931	0x26, 0x36, 0x36, 0x2E, 0x36, 0x36, 0x26, 0x6E, 0x36, 0x36, 0x36, 0x3E, 0x2E, 0x3E, 0x6E, 0xAE,
932	0x4E, 0x5E, 0x5E, 0x6E, 0x5E, 0x5E, 0x6E, 0x4E, 0x5E, 0x5E, 0x5E, 0x7E, 0x6E, 0x7E, 0x4E, 0xCE,
933	0x16, 0x16, 0x16, 0x3E, 0x16, 0x16, 0x36, 0x5E, 0x16, 0x16, 0x16, 0x3E, 0x3E, 0x3E, 0x5E, 0x9E,
934	0x16, 0x16, 0x16, 0x3E, 0x16, 0x16, 0x36, 0x5E, 0x16, 0x16, 0x16, 0x3E, 0x3E, 0x3E, 0x5E, 0x9E,
935	0x16, 0x16, 0x16, 0x3E, 0x16, 0x16, 0x36, 0x5E, 0x16, 0x16, 0x16, 0x3E, 0x3E, 0x3E, 0x5E, 0x9E,
936	0x3E, 0x3E, 0x3E, 0x3E, 0x3E, 0x3E, 0x3E, 0x7E, 0x3E, 0x3E, 0x3E, 0x3E, 0x3E, 0x3E, 0x7E, 0xBE,
937	0x2A, 0x3E, 0x3E, 0x2A, 0x3E, 0x3E, 0x2E, 0x6E, 0x3E, 0x3E, 0x3E, 0x3E, 0x2A, 0x3E, 0x6E, 0xAA,
938	0x3E, 0x3E, 0x3E, 0x3E, 0x3E, 0x3E, 0x3E, 0x7E,	0x3E, 0x3E, 0x3E, 0x3E, 0x3E, 0x3E, 0x7E, 0xBE,
939	0x4E, 0x5E, 0x5E, 0x6E, 0x5E, 0x5E, 0x6E, 0x4E, 0x5E, 0x5E, 0x5E, 0x7E, 0x6E, 0x7E, 0x4E, 0xCE,
940	0x8A, 0x9E, 0x9E, 0xAA, 0x9E, 0x9E, 0xAE, 0xCE, 0x9E, 0x9E, 0x9E, 0xBE, 0xAA, 0xBE, 0xCE, 0x8A,
941};