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v3.1
 
  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_super_block_first * usb1;
 42	struct ufs_cg_private_info * ucpi;
 43	struct ufs_cylinder_group * ucg;
 44	unsigned cgno, bit, end_bit, bbase, blkmap, i;
 45	u64 blkno;
 46	
 47	sb = inode->i_sb;
 48	uspi = UFS_SB(sb)->s_uspi;
 49	usb1 = ubh_get_usb_first(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	lock_super(sb);
 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	fs32_add(sb, &ucg->cg_cs.cs_nffree, count);
 88	uspi->cs_total.cs_nffree += count;
 89	fs32_add(sb, &UFS_SB(sb)->fs_cs(cgno).cs_nffree, count);
 90	blkmap = ubh_blkmap (UCPI_UBH(ucpi), ucpi->c_freeoff, bbase);
 91	ufs_fragacct(sb, blkmap, ucg->cg_frsum, 1);
 92
 93	/*
 94	 * Trying to reassemble free fragments into block
 95	 */
 96	blkno = ufs_fragstoblks (bbase);
 97	if (ubh_isblockset(UCPI_UBH(ucpi), ucpi->c_freeoff, blkno)) {
 98		fs32_sub(sb, &ucg->cg_cs.cs_nffree, uspi->s_fpb);
 99		uspi->cs_total.cs_nffree -= uspi->s_fpb;
100		fs32_sub(sb, &UFS_SB(sb)->fs_cs(cgno).cs_nffree, uspi->s_fpb);
101		if ((UFS_SB(sb)->s_flags & UFS_CG_MASK) == UFS_CG_44BSD)
102			ufs_clusteracct (sb, ucpi, blkno, 1);
103		fs32_add(sb, &ucg->cg_cs.cs_nbfree, 1);
104		uspi->cs_total.cs_nbfree++;
105		fs32_add(sb, &UFS_SB(sb)->fs_cs(cgno).cs_nbfree, 1);
106		if (uspi->fs_magic != UFS2_MAGIC) {
107			unsigned cylno = ufs_cbtocylno (bbase);
108
109			fs16_add(sb, &ubh_cg_blks(ucpi, cylno,
110						  ufs_cbtorpos(bbase)), 1);
111			fs32_add(sb, &ubh_cg_blktot(ucpi, cylno), 1);
112		}
113	}
114	
115	ubh_mark_buffer_dirty (USPI_UBH(uspi));
116	ubh_mark_buffer_dirty (UCPI_UBH(ucpi));
117	if (sb->s_flags & MS_SYNCHRONOUS)
118		ubh_sync_block(UCPI_UBH(ucpi));
119	sb->s_dirt = 1;
120	
121	unlock_super (sb);
122	UFSD("EXIT\n");
123	return;
124
125failed:
126	unlock_super (sb);
127	UFSD("EXIT (FAILED)\n");
128	return;
129}
130
131/*
132 * Free 'count' fragments from fragment number 'fragment' (free whole blocks)
133 */
134void ufs_free_blocks(struct inode *inode, u64 fragment, unsigned count)
135{
136	struct super_block * sb;
137	struct ufs_sb_private_info * uspi;
138	struct ufs_super_block_first * usb1;
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	usb1 = ubh_get_usb_first(uspi);
147
148	UFSD("ENTER, fragment %llu, count %u\n",
149	     (unsigned long long)fragment, count);
150	
151	if ((fragment & uspi->s_fpbmask) || (count & uspi->s_fpbmask)) {
152		ufs_error (sb, "ufs_free_blocks", "internal error, "
153			   "fragment %llu, count %u\n",
154			   (unsigned long long)fragment, count);
155		goto failed;
156	}
157
158	lock_super(sb);
159	
160do_more:
161	overflow = 0;
162	cgno = ufs_dtog(uspi, fragment);
163	bit = ufs_dtogd(uspi, fragment);
164	if (cgno >= uspi->s_ncg) {
165		ufs_panic (sb, "ufs_free_blocks", "freeing blocks are outside device");
166		goto failed_unlock;
167	}
168	end_bit = bit + count;
169	if (end_bit > uspi->s_fpg) {
170		overflow = bit + count - uspi->s_fpg;
171		count -= overflow;
172		end_bit -= overflow;
173	}
174
175	ucpi = ufs_load_cylinder (sb, cgno);
176	if (!ucpi) 
177		goto failed_unlock;
178	ucg = ubh_get_ucg (UCPI_UBH(ucpi));
179	if (!ufs_cg_chkmagic(sb, ucg)) {
180		ufs_panic (sb, "ufs_free_blocks", "internal error, bad magic number on cg %u", cgno);
181		goto failed_unlock;
182	}
183
184	for (i = bit; i < end_bit; i += uspi->s_fpb) {
185		blkno = ufs_fragstoblks(i);
186		if (ubh_isblockset(UCPI_UBH(ucpi), ucpi->c_freeoff, blkno)) {
187			ufs_error(sb, "ufs_free_blocks", "freeing free fragment");
188		}
189		ubh_setblock(UCPI_UBH(ucpi), ucpi->c_freeoff, blkno);
 
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 & MS_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	sb->s_dirt = 1;
218	unlock_super (sb);
219	UFSD("EXIT\n");
220	return;
221
222failed_unlock:
223	unlock_super (sb);
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_CACHE_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_CACHE_SHIFT - inode->i_blkbits);
263	for (i = beg; i < end; i = (i | mask) + 1) {
264		index = i >> (PAGE_CACHE_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(READ, 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			unmap_underlying_metadata(bh->b_bdev,
314						  bh->b_blocknr);
315			mark_buffer_dirty(bh);
316			++j;
317			bh = bh->b_this_page;
318		} while (bh != head);
319
320		if (likely(cur_index != index))
321			ufs_put_locked_page(page);
322 	}
323	UFSD("EXIT\n");
324}
325
326static void ufs_clear_frags(struct inode *inode, sector_t beg, unsigned int n,
327			    int sync)
328{
329	struct buffer_head *bh;
330	sector_t end = beg + n;
331
332	for (; beg < end; ++beg) {
333		bh = sb_getblk(inode->i_sb, beg);
334		lock_buffer(bh);
335		memset(bh->b_data, 0, inode->i_sb->s_blocksize);
336		set_buffer_uptodate(bh);
337		mark_buffer_dirty(bh);
338		unlock_buffer(bh);
339		if (IS_SYNC(inode) || sync)
340			sync_dirty_buffer(bh);
341		brelse(bh);
342	}
343}
344
345u64 ufs_new_fragments(struct inode *inode, void *p, u64 fragment,
346			   u64 goal, unsigned count, int *err,
347			   struct page *locked_page)
348{
349	struct super_block * sb;
350	struct ufs_sb_private_info * uspi;
351	struct ufs_super_block_first * usb1;
352	unsigned cgno, oldcount, newcount;
353	u64 tmp, request, result;
354	
355	UFSD("ENTER, ino %lu, fragment %llu, goal %llu, count %u\n",
356	     inode->i_ino, (unsigned long long)fragment,
357	     (unsigned long long)goal, count);
358	
359	sb = inode->i_sb;
360	uspi = UFS_SB(sb)->s_uspi;
361	usb1 = ubh_get_usb_first(uspi);
362	*err = -ENOSPC;
363
364	lock_super (sb);
365	tmp = ufs_data_ptr_to_cpu(sb, p);
366
367	if (count + ufs_fragnum(fragment) > uspi->s_fpb) {
368		ufs_warning(sb, "ufs_new_fragments", "internal warning"
369			    " fragment %llu, count %u",
370			    (unsigned long long)fragment, count);
371		count = uspi->s_fpb - ufs_fragnum(fragment); 
372	}
373	oldcount = ufs_fragnum (fragment);
374	newcount = oldcount + count;
375
376	/*
377	 * Somebody else has just allocated our fragments
378	 */
379	if (oldcount) {
380		if (!tmp) {
381			ufs_error(sb, "ufs_new_fragments", "internal error, "
382				  "fragment %llu, tmp %llu\n",
383				  (unsigned long long)fragment,
384				  (unsigned long long)tmp);
385			unlock_super(sb);
386			return INVBLOCK;
387		}
388		if (fragment < UFS_I(inode)->i_lastfrag) {
389			UFSD("EXIT (ALREADY ALLOCATED)\n");
390			unlock_super (sb);
391			return 0;
392		}
393	}
394	else {
395		if (tmp) {
396			UFSD("EXIT (ALREADY ALLOCATED)\n");
397			unlock_super(sb);
398			return 0;
399		}
400	}
401
402	/*
403	 * There is not enough space for user on the device
404	 */
405	if (!capable(CAP_SYS_RESOURCE) && ufs_freespace(uspi, UFS_MINFREE) <= 0) {
406		unlock_super (sb);
407		UFSD("EXIT (FAILED)\n");
408		return 0;
 
 
409	}
410
411	if (goal >= uspi->s_size) 
412		goal = 0;
413	if (goal == 0) 
414		cgno = ufs_inotocg (inode->i_ino);
415	else
416		cgno = ufs_dtog(uspi, goal);
417	 
418	/*
419	 * allocate new fragment
420	 */
421	if (oldcount == 0) {
422		result = ufs_alloc_fragments (inode, cgno, goal, count, err);
423		if (result) {
424			ufs_cpu_to_data_ptr(sb, p, result);
 
425			*err = 0;
 
 
426			UFS_I(inode)->i_lastfrag =
427				max(UFS_I(inode)->i_lastfrag, fragment + count);
428			ufs_clear_frags(inode, result + oldcount,
429					newcount - oldcount, locked_page != NULL);
430		}
431		unlock_super(sb);
432		UFSD("EXIT, result %llu\n", (unsigned long long)result);
433		return result;
434	}
435
436	/*
437	 * resize block
438	 */
439	result = ufs_add_fragments (inode, tmp, oldcount, newcount, err);
440	if (result) {
441		*err = 0;
 
442		UFS_I(inode)->i_lastfrag = max(UFS_I(inode)->i_lastfrag,
443						fragment + count);
 
444		ufs_clear_frags(inode, result + oldcount, newcount - oldcount,
445				locked_page != NULL);
446		unlock_super(sb);
447		UFSD("EXIT, result %llu\n", (unsigned long long)result);
448		return result;
449	}
450
451	/*
452	 * allocate new block and move data
453	 */
454	switch (fs32_to_cpu(sb, usb1->fs_optim)) {
455	    case UFS_OPTSPACE:
456		request = newcount;
457		if (uspi->s_minfree < 5 || uspi->cs_total.cs_nffree
458		    > uspi->s_dsize * uspi->s_minfree / (2 * 100))
459			break;
460		usb1->fs_optim = cpu_to_fs32(sb, UFS_OPTTIME);
461		break;
462	    default:
463		usb1->fs_optim = cpu_to_fs32(sb, UFS_OPTTIME);
464	
465	    case UFS_OPTTIME:
466		request = uspi->s_fpb;
467		if (uspi->cs_total.cs_nffree < uspi->s_dsize *
468		    (uspi->s_minfree - 2) / 100)
469			break;
470		usb1->fs_optim = cpu_to_fs32(sb, UFS_OPTTIME);
471		break;
472	}
473	result = ufs_alloc_fragments (inode, cgno, goal, request, err);
474	if (result) {
475		ufs_clear_frags(inode, result + oldcount, newcount - oldcount,
476				locked_page != NULL);
 
477		ufs_change_blocknr(inode, fragment - oldcount, oldcount,
478				   uspi->s_sbbase + tmp,
479				   uspi->s_sbbase + result, locked_page);
480		ufs_cpu_to_data_ptr(sb, p, result);
481		*err = 0;
 
 
482		UFS_I(inode)->i_lastfrag = max(UFS_I(inode)->i_lastfrag,
483						fragment + count);
484		unlock_super(sb);
485		if (newcount < request)
486			ufs_free_fragments (inode, result + newcount, request - newcount);
487		ufs_free_fragments (inode, tmp, oldcount);
488		UFSD("EXIT, result %llu\n", (unsigned long long)result);
489		return result;
490	}
491
492	unlock_super(sb);
493	UFSD("EXIT (FAILED)\n");
494	return 0;
495}		
496
 
 
 
 
 
 
 
 
 
 
 
 
 
 
497static u64 ufs_add_fragments(struct inode *inode, u64 fragment,
498			     unsigned oldcount, unsigned newcount, int *err)
499{
500	struct super_block * sb;
501	struct ufs_sb_private_info * uspi;
502	struct ufs_super_block_first * usb1;
503	struct ufs_cg_private_info * ucpi;
504	struct ufs_cylinder_group * ucg;
505	unsigned cgno, fragno, fragoff, count, fragsize, i;
506	
507	UFSD("ENTER, fragment %llu, oldcount %u, newcount %u\n",
508	     (unsigned long long)fragment, oldcount, newcount);
509	
510	sb = inode->i_sb;
511	uspi = UFS_SB(sb)->s_uspi;
512	usb1 = ubh_get_usb_first (uspi);
513	count = newcount - oldcount;
514	
515	cgno = ufs_dtog(uspi, fragment);
516	if (fs32_to_cpu(sb, UFS_SB(sb)->fs_cs(cgno).cs_nffree) < count)
517		return 0;
518	if ((ufs_fragnum (fragment) + newcount) > uspi->s_fpb)
519		return 0;
520	ucpi = ufs_load_cylinder (sb, cgno);
521	if (!ucpi)
522		return 0;
523	ucg = ubh_get_ucg (UCPI_UBH(ucpi));
524	if (!ufs_cg_chkmagic(sb, ucg)) {
525		ufs_panic (sb, "ufs_add_fragments",
526			"internal error, bad magic number on cg %u", cgno);
527		return 0;
528	}
529
530	fragno = ufs_dtogd(uspi, fragment);
531	fragoff = ufs_fragnum (fragno);
532	for (i = oldcount; i < newcount; i++)
533		if (ubh_isclr (UCPI_UBH(ucpi), ucpi->c_freeoff, fragno + i))
534			return 0;
 
 
 
535	/*
536	 * Block can be extended
537	 */
538	ucg->cg_time = cpu_to_fs32(sb, get_seconds());
539	for (i = newcount; i < (uspi->s_fpb - fragoff); i++)
540		if (ubh_isclr (UCPI_UBH(ucpi), ucpi->c_freeoff, fragno + i))
541			break;
542	fragsize = i - oldcount;
543	if (!fs32_to_cpu(sb, ucg->cg_frsum[fragsize]))
544		ufs_panic (sb, "ufs_add_fragments",
545			"internal error or corrupted bitmap on cg %u", cgno);
546	fs32_sub(sb, &ucg->cg_frsum[fragsize], 1);
547	if (fragsize != count)
548		fs32_add(sb, &ucg->cg_frsum[fragsize - count], 1);
549	for (i = oldcount; i < newcount; i++)
550		ubh_clrbit (UCPI_UBH(ucpi), ucpi->c_freeoff, fragno + i);
551
552	fs32_sub(sb, &ucg->cg_cs.cs_nffree, count);
553	fs32_sub(sb, &UFS_SB(sb)->fs_cs(cgno).cs_nffree, count);
554	uspi->cs_total.cs_nffree -= count;
555	
556	ubh_mark_buffer_dirty (USPI_UBH(uspi));
557	ubh_mark_buffer_dirty (UCPI_UBH(ucpi));
558	if (sb->s_flags & MS_SYNCHRONOUS)
559		ubh_sync_block(UCPI_UBH(ucpi));
560	sb->s_dirt = 1;
561
562	UFSD("EXIT, fragment %llu\n", (unsigned long long)fragment);
563	
564	return fragment;
565}
566
567#define UFS_TEST_FREE_SPACE_CG \
568	ucg = (struct ufs_cylinder_group *) UFS_SB(sb)->s_ucg[cgno]->b_data; \
569	if (fs32_to_cpu(sb, ucg->cg_cs.cs_nbfree)) \
570		goto cg_found; \
571	for (k = count; k < uspi->s_fpb; k++) \
572		if (fs32_to_cpu(sb, ucg->cg_frsum[k])) \
573			goto cg_found; 
574
575static u64 ufs_alloc_fragments(struct inode *inode, unsigned cgno,
576			       u64 goal, unsigned count, int *err)
577{
578	struct super_block * sb;
579	struct ufs_sb_private_info * uspi;
580	struct ufs_super_block_first * usb1;
581	struct ufs_cg_private_info * ucpi;
582	struct ufs_cylinder_group * ucg;
583	unsigned oldcg, i, j, k, allocsize;
584	u64 result;
585	
586	UFSD("ENTER, ino %lu, cgno %u, goal %llu, count %u\n",
587	     inode->i_ino, cgno, (unsigned long long)goal, count);
588
589	sb = inode->i_sb;
590	uspi = UFS_SB(sb)->s_uspi;
591	usb1 = ubh_get_usb_first(uspi);
592	oldcg = cgno;
593	
594	/*
595	 * 1. searching on preferred cylinder group
596	 */
597	UFS_TEST_FREE_SPACE_CG
598
599	/*
600	 * 2. quadratic rehash
601	 */
602	for (j = 1; j < uspi->s_ncg; j *= 2) {
603		cgno += j;
604		if (cgno >= uspi->s_ncg) 
605			cgno -= uspi->s_ncg;
606		UFS_TEST_FREE_SPACE_CG
607	}
608
609	/*
610	 * 3. brute force search
611	 * We start at i = 2 ( 0 is checked at 1.step, 1 at 2.step )
612	 */
613	cgno = (oldcg + 1) % uspi->s_ncg;
614	for (j = 2; j < uspi->s_ncg; j++) {
615		cgno++;
616		if (cgno >= uspi->s_ncg)
617			cgno = 0;
618		UFS_TEST_FREE_SPACE_CG
619	}
620	
621	UFSD("EXIT (FAILED)\n");
622	return 0;
623
624cg_found:
625	ucpi = ufs_load_cylinder (sb, cgno);
626	if (!ucpi)
627		return 0;
628	ucg = ubh_get_ucg (UCPI_UBH(ucpi));
629	if (!ufs_cg_chkmagic(sb, ucg)) 
630		ufs_panic (sb, "ufs_alloc_fragments",
631			"internal error, bad magic number on cg %u", cgno);
632	ucg->cg_time = cpu_to_fs32(sb, get_seconds());
633
634	if (count == uspi->s_fpb) {
635		result = ufs_alloccg_block (inode, ucpi, goal, err);
636		if (result == INVBLOCK)
637			return 0;
638		goto succed;
639	}
640
641	for (allocsize = count; allocsize < uspi->s_fpb; allocsize++)
642		if (fs32_to_cpu(sb, ucg->cg_frsum[allocsize]) != 0)
643			break;
644	
645	if (allocsize == uspi->s_fpb) {
646		result = ufs_alloccg_block (inode, ucpi, goal, err);
647		if (result == INVBLOCK)
648			return 0;
649		goal = ufs_dtogd(uspi, result);
650		for (i = count; i < uspi->s_fpb; i++)
651			ubh_setbit (UCPI_UBH(ucpi), ucpi->c_freeoff, goal + i);
652		i = uspi->s_fpb - count;
653
 
654		fs32_add(sb, &ucg->cg_cs.cs_nffree, i);
655		uspi->cs_total.cs_nffree += i;
656		fs32_add(sb, &UFS_SB(sb)->fs_cs(cgno).cs_nffree, i);
657		fs32_add(sb, &ucg->cg_frsum[i], 1);
658		goto succed;
659	}
660
661	result = ufs_bitmap_search (sb, ucpi, goal, allocsize);
662	if (result == INVBLOCK)
663		return 0;
 
 
664	for (i = 0; i < count; i++)
665		ubh_clrbit (UCPI_UBH(ucpi), ucpi->c_freeoff, result + i);
666	
667	fs32_sub(sb, &ucg->cg_cs.cs_nffree, count);
668	uspi->cs_total.cs_nffree -= count;
669	fs32_sub(sb, &UFS_SB(sb)->fs_cs(cgno).cs_nffree, count);
670	fs32_sub(sb, &ucg->cg_frsum[allocsize], 1);
671
672	if (count != allocsize)
673		fs32_add(sb, &ucg->cg_frsum[allocsize - count], 1);
674
675succed:
676	ubh_mark_buffer_dirty (USPI_UBH(uspi));
677	ubh_mark_buffer_dirty (UCPI_UBH(ucpi));
678	if (sb->s_flags & MS_SYNCHRONOUS)
679		ubh_sync_block(UCPI_UBH(ucpi));
680	sb->s_dirt = 1;
681
682	result += cgno * uspi->s_fpg;
683	UFSD("EXIT3, result %llu\n", (unsigned long long)result);
684	return result;
685}
686
687static u64 ufs_alloccg_block(struct inode *inode,
688			     struct ufs_cg_private_info *ucpi,
689			     u64 goal, int *err)
690{
691	struct super_block * sb;
692	struct ufs_sb_private_info * uspi;
693	struct ufs_super_block_first * usb1;
694	struct ufs_cylinder_group * ucg;
695	u64 result, blkno;
696
697	UFSD("ENTER, goal %llu\n", (unsigned long long)goal);
698
699	sb = inode->i_sb;
700	uspi = UFS_SB(sb)->s_uspi;
701	usb1 = ubh_get_usb_first(uspi);
702	ucg = ubh_get_ucg(UCPI_UBH(ucpi));
703
704	if (goal == 0) {
705		goal = ucpi->c_rotor;
706		goto norot;
707	}
708	goal = ufs_blknum (goal);
709	goal = ufs_dtogd(uspi, goal);
710	
711	/*
712	 * If the requested block is available, use it.
713	 */
714	if (ubh_isblockset(UCPI_UBH(ucpi), ucpi->c_freeoff, ufs_fragstoblks(goal))) {
715		result = goal;
716		goto gotit;
717	}
718	
719norot:	
720	result = ufs_bitmap_search (sb, ucpi, goal, uspi->s_fpb);
721	if (result == INVBLOCK)
722		return INVBLOCK;
723	ucpi->c_rotor = result;
724gotit:
 
 
725	blkno = ufs_fragstoblks(result);
726	ubh_clrblock (UCPI_UBH(ucpi), ucpi->c_freeoff, blkno);
727	if ((UFS_SB(sb)->s_flags & UFS_CG_MASK) == UFS_CG_44BSD)
728		ufs_clusteracct (sb, ucpi, blkno, -1);
729
730	fs32_sub(sb, &ucg->cg_cs.cs_nbfree, 1);
731	uspi->cs_total.cs_nbfree--;
732	fs32_sub(sb, &UFS_SB(sb)->fs_cs(ucpi->c_cgx).cs_nbfree, 1);
733
734	if (uspi->fs_magic != UFS2_MAGIC) {
735		unsigned cylno = ufs_cbtocylno((unsigned)result);
736
737		fs16_sub(sb, &ubh_cg_blks(ucpi, cylno,
738					  ufs_cbtorpos((unsigned)result)), 1);
739		fs32_sub(sb, &ubh_cg_blktot(ucpi, cylno), 1);
740	}
741	
742	UFSD("EXIT, result %llu\n", (unsigned long long)result);
743
744	return result;
745}
746
747static unsigned ubh_scanc(struct ufs_sb_private_info *uspi,
748			  struct ufs_buffer_head *ubh,
749			  unsigned begin, unsigned size,
750			  unsigned char *table, unsigned char mask)
751{
752	unsigned rest, offset;
753	unsigned char *cp;
754	
755
756	offset = begin & ~uspi->s_fmask;
757	begin >>= uspi->s_fshift;
758	for (;;) {
759		if ((offset + size) < uspi->s_fsize)
760			rest = size;
761		else
762			rest = uspi->s_fsize - offset;
763		size -= rest;
764		cp = ubh->bh[begin]->b_data + offset;
765		while ((table[*cp++] & mask) == 0 && --rest)
766			;
767		if (rest || !size)
768			break;
769		begin++;
770		offset = 0;
771	}
772	return (size + rest);
773}
774
775/*
776 * Find a block of the specified size in the specified cylinder group.
777 * @sp: pointer to super block
778 * @ucpi: pointer to cylinder group info
779 * @goal: near which block we want find new one
780 * @count: specified size
781 */
782static u64 ufs_bitmap_search(struct super_block *sb,
783			     struct ufs_cg_private_info *ucpi,
784			     u64 goal, unsigned count)
785{
786	/*
787	 * Bit patterns for identifying fragments in the block map
788	 * used as ((map & mask_arr) == want_arr)
789	 */
790	static const int mask_arr[9] = {
791		0x3, 0x7, 0xf, 0x1f, 0x3f, 0x7f, 0xff, 0x1ff, 0x3ff
792	};
793	static const int want_arr[9] = {
794		0x0, 0x2, 0x6, 0xe, 0x1e, 0x3e, 0x7e, 0xfe, 0x1fe
795	};
796	struct ufs_sb_private_info *uspi = UFS_SB(sb)->s_uspi;
797	struct ufs_super_block_first *usb1;
798	struct ufs_cylinder_group *ucg;
799	unsigned start, length, loc;
800	unsigned pos, want, blockmap, mask, end;
801	u64 result;
802
803	UFSD("ENTER, cg %u, goal %llu, count %u\n", ucpi->c_cgx,
804	     (unsigned long long)goal, count);
805
806	usb1 = ubh_get_usb_first (uspi);
807	ucg = ubh_get_ucg(UCPI_UBH(ucpi));
808
809	if (goal)
810		start = ufs_dtogd(uspi, goal) >> 3;
811	else
812		start = ucpi->c_frotor >> 3;
813		
814	length = ((uspi->s_fpg + 7) >> 3) - start;
815	loc = ubh_scanc(uspi, UCPI_UBH(ucpi), ucpi->c_freeoff + start, length,
816		(uspi->s_fpb == 8) ? ufs_fragtable_8fpb : ufs_fragtable_other,
817		1 << (count - 1 + (uspi->s_fpb & 7))); 
818	if (loc == 0) {
819		length = start + 1;
820		loc = ubh_scanc(uspi, UCPI_UBH(ucpi), ucpi->c_freeoff, length,
821				(uspi->s_fpb == 8) ? ufs_fragtable_8fpb :
822				ufs_fragtable_other,
823				1 << (count - 1 + (uspi->s_fpb & 7)));
824		if (loc == 0) {
825			ufs_error(sb, "ufs_bitmap_search",
826				  "bitmap corrupted on cg %u, start %u,"
827				  " length %u, count %u, freeoff %u\n",
828				  ucpi->c_cgx, start, length, count,
829				  ucpi->c_freeoff);
830			return INVBLOCK;
831		}
832		start = 0;
833	}
834	result = (start + length - loc) << 3;
835	ucpi->c_frotor = result;
836
837	/*
838	 * found the byte in the map
839	 */
840
841	for (end = result + 8; result < end; result += uspi->s_fpb) {
842		blockmap = ubh_blkmap(UCPI_UBH(ucpi), ucpi->c_freeoff, result);
843		blockmap <<= 1;
844		mask = mask_arr[count];
845		want = want_arr[count];
846		for (pos = 0; pos <= uspi->s_fpb - count; pos++) {
847			if ((blockmap & mask) == want) {
848				UFSD("EXIT, result %llu\n",
849				     (unsigned long long)result);
850				return result + pos;
851 			}
852			mask <<= 1;
853			want <<= 1;
854 		}
855 	}
856
857	ufs_error(sb, "ufs_bitmap_search", "block not in map on cg %u\n",
858		  ucpi->c_cgx);
859	UFSD("EXIT (FAILED)\n");
860	return INVBLOCK;
861}
862
863static void ufs_clusteracct(struct super_block * sb,
864	struct ufs_cg_private_info * ucpi, unsigned blkno, int cnt)
865{
866	struct ufs_sb_private_info * uspi;
867	int i, start, end, forw, back;
868	
869	uspi = UFS_SB(sb)->s_uspi;
870	if (uspi->s_contigsumsize <= 0)
871		return;
872
873	if (cnt > 0)
874		ubh_setbit(UCPI_UBH(ucpi), ucpi->c_clusteroff, blkno);
875	else
876		ubh_clrbit(UCPI_UBH(ucpi), ucpi->c_clusteroff, blkno);
877
878	/*
879	 * Find the size of the cluster going forward.
880	 */
881	start = blkno + 1;
882	end = start + uspi->s_contigsumsize;
883	if ( end >= ucpi->c_nclusterblks)
884		end = ucpi->c_nclusterblks;
885	i = ubh_find_next_zero_bit (UCPI_UBH(ucpi), ucpi->c_clusteroff, end, start);
886	if (i > end)
887		i = end;
888	forw = i - start;
889	
890	/*
891	 * Find the size of the cluster going backward.
892	 */
893	start = blkno - 1;
894	end = start - uspi->s_contigsumsize;
895	if (end < 0 ) 
896		end = -1;
897	i = ubh_find_last_zero_bit (UCPI_UBH(ucpi), ucpi->c_clusteroff, start, end);
898	if ( i < end) 
899		i = end;
900	back = start - i;
901	
902	/*
903	 * Account for old cluster and the possibly new forward and
904	 * back clusters.
905	 */
906	i = back + forw + 1;
907	if (i > uspi->s_contigsumsize)
908		i = uspi->s_contigsumsize;
909	fs32_add(sb, (__fs32*)ubh_get_addr(UCPI_UBH(ucpi), ucpi->c_clustersumoff + (i << 2)), cnt);
910	if (back > 0)
911		fs32_sub(sb, (__fs32*)ubh_get_addr(UCPI_UBH(ucpi), ucpi->c_clustersumoff + (back << 2)), cnt);
912	if (forw > 0)
913		fs32_sub(sb, (__fs32*)ubh_get_addr(UCPI_UBH(ucpi), ucpi->c_clustersumoff + (forw << 2)), cnt);
914}
915
916
917static unsigned char ufs_fragtable_8fpb[] = {
918	0x00, 0x01, 0x01, 0x02, 0x01, 0x01, 0x02, 0x04, 0x01, 0x01, 0x01, 0x03, 0x02, 0x03, 0x04, 0x08,
919	0x01, 0x01, 0x01, 0x03, 0x01, 0x01, 0x03, 0x05, 0x02, 0x03, 0x03, 0x02, 0x04, 0x05, 0x08, 0x10,
920	0x01, 0x01, 0x01, 0x03, 0x01, 0x01, 0x03, 0x05, 0x01, 0x01, 0x01, 0x03, 0x03, 0x03, 0x05, 0x09,
921	0x02, 0x03, 0x03, 0x02, 0x03, 0x03, 0x02, 0x06, 0x04, 0x05, 0x05, 0x06, 0x08, 0x09, 0x10, 0x20,
922	0x01, 0x01, 0x01, 0x03, 0x01, 0x01, 0x03, 0x05, 0x01, 0x01, 0x01, 0x03, 0x03, 0x03, 0x05, 0x09,	
923	0x01, 0x01, 0x01, 0x03, 0x01, 0x01, 0x03, 0x05, 0x03, 0x03, 0x03, 0x03, 0x05, 0x05, 0x09, 0x11,
924	0x02, 0x03, 0x03, 0x02, 0x03, 0x03, 0x02, 0x06, 0x03, 0x03, 0x03, 0x03, 0x02, 0x03, 0x06, 0x0A,
925	0x04, 0x05, 0x05, 0x06, 0x05, 0x05, 0x06, 0x04, 0x08, 0x09, 0x09, 0x0A, 0x10, 0x11, 0x20, 0x40,
926	0x01, 0x01, 0x01, 0x03, 0x01, 0x01, 0x03, 0x05, 0x01, 0x01, 0x01, 0x03, 0x03, 0x03, 0x05, 0x09,
927	0x01, 0x01, 0x01, 0x03, 0x01, 0x01, 0x03, 0x05, 0x03, 0x03, 0x03, 0x03, 0x05, 0x05, 0x09, 0x11,
928	0x01, 0x01, 0x01, 0x03, 0x01, 0x01, 0x03, 0x05, 0x01, 0x01, 0x01, 0x03, 0x03, 0x03, 0x05, 0x09,
929	0x03, 0x03, 0x03, 0x03, 0x03, 0x03, 0x03, 0x07, 0x05, 0x05, 0x05, 0x07, 0x09, 0x09, 0x11, 0x21,
930	0x02, 0x03, 0x03, 0x02, 0x03, 0x03, 0x02, 0x06, 0x03, 0x03, 0x03, 0x03, 0x02, 0x03, 0x06, 0x0A,
931	0x03, 0x03, 0x03, 0x03, 0x03, 0x03, 0x03, 0x07, 0x02, 0x03, 0x03, 0x02, 0x06, 0x07, 0x0A, 0x12,
932	0x04, 0x05, 0x05, 0x06, 0x05, 0x05, 0x06, 0x04, 0x05, 0x05, 0x05, 0x07, 0x06, 0x07, 0x04, 0x0C,
933	0x08, 0x09, 0x09, 0x0A, 0x09, 0x09, 0x0A, 0x0C, 0x10, 0x11, 0x11, 0x12, 0x20, 0x21, 0x40, 0x80,
934};
935
936static unsigned char ufs_fragtable_other[] = {
937	0x00, 0x16, 0x16, 0x2A, 0x16, 0x16, 0x26, 0x4E, 0x16, 0x16, 0x16, 0x3E, 0x2A, 0x3E, 0x4E, 0x8A,
938	0x16, 0x16, 0x16, 0x3E, 0x16, 0x16, 0x36, 0x5E, 0x16, 0x16, 0x16, 0x3E, 0x3E, 0x3E, 0x5E, 0x9E,
939	0x16, 0x16, 0x16, 0x3E, 0x16, 0x16, 0x36, 0x5E, 0x16, 0x16, 0x16, 0x3E, 0x3E, 0x3E, 0x5E, 0x9E,
940	0x2A, 0x3E, 0x3E, 0x2A, 0x3E, 0x3E, 0x2E, 0x6E, 0x3E, 0x3E, 0x3E, 0x3E, 0x2A, 0x3E, 0x6E, 0xAA,
941	0x16, 0x16, 0x16, 0x3E, 0x16, 0x16, 0x36, 0x5E, 0x16, 0x16, 0x16, 0x3E, 0x3E, 0x3E, 0x5E, 0x9E,
942	0x16, 0x16, 0x16, 0x3E, 0x16, 0x16, 0x36, 0x5E, 0x16, 0x16, 0x16, 0x3E, 0x3E, 0x3E, 0x5E, 0x9E,
943	0x26, 0x36, 0x36, 0x2E, 0x36, 0x36, 0x26, 0x6E, 0x36, 0x36, 0x36, 0x3E, 0x2E, 0x3E, 0x6E, 0xAE,
944	0x4E, 0x5E, 0x5E, 0x6E, 0x5E, 0x5E, 0x6E, 0x4E, 0x5E, 0x5E, 0x5E, 0x7E, 0x6E, 0x7E, 0x4E, 0xCE,
945	0x16, 0x16, 0x16, 0x3E, 0x16, 0x16, 0x36, 0x5E, 0x16, 0x16, 0x16, 0x3E, 0x3E, 0x3E, 0x5E, 0x9E,
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	0x3E, 0x3E, 0x3E, 0x3E, 0x3E, 0x3E, 0x3E, 0x7E, 0x3E, 0x3E, 0x3E, 0x3E, 0x3E, 0x3E, 0x7E, 0xBE,
949	0x2A, 0x3E, 0x3E, 0x2A, 0x3E, 0x3E, 0x2E, 0x6E, 0x3E, 0x3E, 0x3E, 0x3E, 0x2A, 0x3E, 0x6E, 0xAA,
950	0x3E, 0x3E, 0x3E, 0x3E, 0x3E, 0x3E, 0x3E, 0x7E,	0x3E, 0x3E, 0x3E, 0x3E, 0x3E, 0x3E, 0x7E, 0xBE,
951	0x4E, 0x5E, 0x5E, 0x6E, 0x5E, 0x5E, 0x6E, 0x4E, 0x5E, 0x5E, 0x5E, 0x7E, 0x6E, 0x7E, 0x4E, 0xCE,
952	0x8A, 0x9E, 0x9E, 0xAA, 0x9E, 0x9E, 0xAE, 0xCE, 0x9E, 0x9E, 0x9E, 0xBE, 0xAA, 0xBE, 0xCE, 0x8A,
953};
v5.14.15
  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 = ufs_get_seconds(sb);
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 = ufs_get_seconds(sb);
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};