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1 | /* |
2 | * Copyright (C) International Business Machines Corp., 2000-2004 |
3 | * |
4 | * This program is free software; you can redistribute it and/or modify |
5 | * it under the terms of the GNU General Public License as published by |
6 | * the Free Software Foundation; either version 2 of the License, or |
7 | * (at your option) any later version. |
8 | * |
9 | * This program is distributed in the hope that it will be useful, |
10 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
11 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See |
12 | * the GNU General Public License for more details. |
13 | * |
14 | * You should have received a copy of the GNU General Public License |
15 | * along with this program; if not, write to the Free Software |
16 | * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA |
17 | */ |
18 | |
19 | #include <linux/fs.h> |
20 | #include <linux/quotaops.h> |
21 | #include "jfs_incore.h" |
22 | #include "jfs_inode.h" |
23 | #include "jfs_superblock.h" |
24 | #include "jfs_dmap.h" |
25 | #include "jfs_extent.h" |
26 | #include "jfs_debug.h" |
27 | |
28 | /* |
29 | * forward references |
30 | */ |
31 | static int extBalloc(struct inode *, s64, s64 *, s64 *); |
32 | #ifdef _NOTYET |
33 | static int extBrealloc(struct inode *, s64, s64, s64 *, s64 *); |
34 | #endif |
35 | static s64 extRoundDown(s64 nb); |
36 | |
37 | #define DPD(a) (printk("(a): %d\n",(a))) |
38 | #define DPC(a) (printk("(a): %c\n",(a))) |
39 | #define DPL1(a) \ |
40 | { \ |
41 | if ((a) >> 32) \ |
42 | printk("(a): %x%08x ",(a)); \ |
43 | else \ |
44 | printk("(a): %x ",(a) << 32); \ |
45 | } |
46 | #define DPL(a) \ |
47 | { \ |
48 | if ((a) >> 32) \ |
49 | printk("(a): %x%08x\n",(a)); \ |
50 | else \ |
51 | printk("(a): %x\n",(a) << 32); \ |
52 | } |
53 | |
54 | #define DPD1(a) (printk("(a): %d ",(a))) |
55 | #define DPX(a) (printk("(a): %08x\n",(a))) |
56 | #define DPX1(a) (printk("(a): %08x ",(a))) |
57 | #define DPS(a) (printk("%s\n",(a))) |
58 | #define DPE(a) (printk("\nENTERING: %s\n",(a))) |
59 | #define DPE1(a) (printk("\nENTERING: %s",(a))) |
60 | #define DPS1(a) (printk(" %s ",(a))) |
61 | |
62 | |
63 | /* |
64 | * NAME: extAlloc() |
65 | * |
66 | * FUNCTION: allocate an extent for a specified page range within a |
67 | * file. |
68 | * |
69 | * PARAMETERS: |
70 | * ip - the inode of the file. |
71 | * xlen - requested extent length. |
72 | * pno - the starting page number with the file. |
73 | * xp - pointer to an xad. on entry, xad describes an |
74 | * extent that is used as an allocation hint if the |
75 | * xaddr of the xad is non-zero. on successful exit, |
76 | * the xad describes the newly allocated extent. |
77 | * abnr - bool indicating whether the newly allocated extent |
78 | * should be marked as allocated but not recorded. |
79 | * |
80 | * RETURN VALUES: |
81 | * 0 - success |
82 | * -EIO - i/o error. |
83 | * -ENOSPC - insufficient disk resources. |
84 | */ |
85 | int |
86 | extAlloc(struct inode *ip, s64 xlen, s64 pno, xad_t * xp, bool abnr) |
87 | { |
88 | struct jfs_sb_info *sbi = JFS_SBI(ip->i_sb); |
89 | s64 nxlen, nxaddr, xoff, hint, xaddr = 0; |
90 | int rc; |
91 | int xflag; |
92 | |
93 | /* This blocks if we are low on resources */ |
94 | txBeginAnon(ip->i_sb); |
95 | |
96 | /* Avoid race with jfs_commit_inode() */ |
97 | mutex_lock(&JFS_IP(ip)->commit_mutex); |
98 | |
99 | /* validate extent length */ |
100 | if (xlen > MAXXLEN) |
101 | xlen = MAXXLEN; |
102 | |
103 | /* get the page's starting extent offset */ |
104 | xoff = pno << sbi->l2nbperpage; |
105 | |
106 | /* check if an allocation hint was provided */ |
107 | if ((hint = addressXAD(xp))) { |
108 | /* get the size of the extent described by the hint */ |
109 | nxlen = lengthXAD(xp); |
110 | |
111 | /* check if the hint is for the portion of the file |
112 | * immediately previous to the current allocation |
113 | * request and if hint extent has the same abnr |
114 | * value as the current request. if so, we can |
115 | * extend the hint extent to include the current |
116 | * extent if we can allocate the blocks immediately |
117 | * following the hint extent. |
118 | */ |
119 | if (offsetXAD(xp) + nxlen == xoff && |
120 | abnr == ((xp->flag & XAD_NOTRECORDED) ? true : false)) |
121 | xaddr = hint + nxlen; |
122 | |
123 | /* adjust the hint to the last block of the extent */ |
124 | hint += (nxlen - 1); |
125 | } |
126 | |
127 | /* allocate the disk blocks for the extent. initially, extBalloc() |
128 | * will try to allocate disk blocks for the requested size (xlen). |
129 | * if this fails (xlen contiguous free blocks not available), it'll |
130 | * try to allocate a smaller number of blocks (producing a smaller |
131 | * extent), with this smaller number of blocks consisting of the |
132 | * requested number of blocks rounded down to the next smaller |
133 | * power of 2 number (i.e. 16 -> 8). it'll continue to round down |
134 | * and retry the allocation until the number of blocks to allocate |
135 | * is smaller than the number of blocks per page. |
136 | */ |
137 | nxlen = xlen; |
138 | if ((rc = extBalloc(ip, hint ? hint : INOHINT(ip), &nxlen, &nxaddr))) { |
139 | mutex_unlock(&JFS_IP(ip)->commit_mutex); |
140 | return (rc); |
141 | } |
142 | |
143 | /* Allocate blocks to quota. */ |
144 | rc = dquot_alloc_block(ip, nxlen); |
145 | if (rc) { |
146 | dbFree(ip, nxaddr, (s64) nxlen); |
147 | mutex_unlock(&JFS_IP(ip)->commit_mutex); |
148 | return rc; |
149 | } |
150 | |
151 | /* determine the value of the extent flag */ |
152 | xflag = abnr ? XAD_NOTRECORDED : 0; |
153 | |
154 | /* if we can extend the hint extent to cover the current request, |
155 | * extend it. otherwise, insert a new extent to |
156 | * cover the current request. |
157 | */ |
158 | if (xaddr && xaddr == nxaddr) |
159 | rc = xtExtend(0, ip, xoff, (int) nxlen, 0); |
160 | else |
161 | rc = xtInsert(0, ip, xflag, xoff, (int) nxlen, &nxaddr, 0); |
162 | |
163 | /* if the extend or insert failed, |
164 | * free the newly allocated blocks and return the error. |
165 | */ |
166 | if (rc) { |
167 | dbFree(ip, nxaddr, nxlen); |
168 | dquot_free_block(ip, nxlen); |
169 | mutex_unlock(&JFS_IP(ip)->commit_mutex); |
170 | return (rc); |
171 | } |
172 | |
173 | /* set the results of the extent allocation */ |
174 | XADaddress(xp, nxaddr); |
175 | XADlength(xp, nxlen); |
176 | XADoffset(xp, xoff); |
177 | xp->flag = xflag; |
178 | |
179 | mark_inode_dirty(ip); |
180 | |
181 | mutex_unlock(&JFS_IP(ip)->commit_mutex); |
182 | /* |
183 | * COMMIT_SyncList flags an anonymous tlock on page that is on |
184 | * sync list. |
185 | * We need to commit the inode to get the page written disk. |
186 | */ |
187 | if (test_and_clear_cflag(COMMIT_Synclist,ip)) |
188 | jfs_commit_inode(ip, 0); |
189 | |
190 | return (0); |
191 | } |
192 | |
193 | |
194 | #ifdef _NOTYET |
195 | /* |
196 | * NAME: extRealloc() |
197 | * |
198 | * FUNCTION: extend the allocation of a file extent containing a |
199 | * partial back last page. |
200 | * |
201 | * PARAMETERS: |
202 | * ip - the inode of the file. |
203 | * cp - cbuf for the partial backed last page. |
204 | * xlen - request size of the resulting extent. |
205 | * xp - pointer to an xad. on successful exit, the xad |
206 | * describes the newly allocated extent. |
207 | * abnr - bool indicating whether the newly allocated extent |
208 | * should be marked as allocated but not recorded. |
209 | * |
210 | * RETURN VALUES: |
211 | * 0 - success |
212 | * -EIO - i/o error. |
213 | * -ENOSPC - insufficient disk resources. |
214 | */ |
215 | int extRealloc(struct inode *ip, s64 nxlen, xad_t * xp, bool abnr) |
216 | { |
217 | struct super_block *sb = ip->i_sb; |
218 | s64 xaddr, xlen, nxaddr, delta, xoff; |
219 | s64 ntail, nextend, ninsert; |
220 | int rc, nbperpage = JFS_SBI(sb)->nbperpage; |
221 | int xflag; |
222 | |
223 | /* This blocks if we are low on resources */ |
224 | txBeginAnon(ip->i_sb); |
225 | |
226 | mutex_lock(&JFS_IP(ip)->commit_mutex); |
227 | /* validate extent length */ |
228 | if (nxlen > MAXXLEN) |
229 | nxlen = MAXXLEN; |
230 | |
231 | /* get the extend (partial) page's disk block address and |
232 | * number of blocks. |
233 | */ |
234 | xaddr = addressXAD(xp); |
235 | xlen = lengthXAD(xp); |
236 | xoff = offsetXAD(xp); |
237 | |
238 | /* if the extend page is abnr and if the request is for |
239 | * the extent to be allocated and recorded, |
240 | * make the page allocated and recorded. |
241 | */ |
242 | if ((xp->flag & XAD_NOTRECORDED) && !abnr) { |
243 | xp->flag = 0; |
244 | if ((rc = xtUpdate(0, ip, xp))) |
245 | goto exit; |
246 | } |
247 | |
248 | /* try to allocated the request number of blocks for the |
249 | * extent. dbRealloc() first tries to satisfy the request |
250 | * by extending the allocation in place. otherwise, it will |
251 | * try to allocate a new set of blocks large enough for the |
252 | * request. in satisfying a request, dbReAlloc() may allocate |
253 | * less than what was request but will always allocate enough |
254 | * space as to satisfy the extend page. |
255 | */ |
256 | if ((rc = extBrealloc(ip, xaddr, xlen, &nxlen, &nxaddr))) |
257 | goto exit; |
258 | |
259 | /* Allocat blocks to quota. */ |
260 | rc = dquot_alloc_block(ip, nxlen); |
261 | if (rc) { |
262 | dbFree(ip, nxaddr, (s64) nxlen); |
263 | mutex_unlock(&JFS_IP(ip)->commit_mutex); |
264 | return rc; |
265 | } |
266 | |
267 | delta = nxlen - xlen; |
268 | |
269 | /* check if the extend page is not abnr but the request is abnr |
270 | * and the allocated disk space is for more than one page. if this |
271 | * is the case, there is a miss match of abnr between the extend page |
272 | * and the one or more pages following the extend page. as a result, |
273 | * two extents will have to be manipulated. the first will be that |
274 | * of the extent of the extend page and will be manipulated thru |
275 | * an xtExtend() or an xtTailgate(), depending upon whether the |
276 | * disk allocation occurred as an inplace extension. the second |
277 | * extent will be manipulated (created) through an xtInsert() and |
278 | * will be for the pages following the extend page. |
279 | */ |
280 | if (abnr && (!(xp->flag & XAD_NOTRECORDED)) && (nxlen > nbperpage)) { |
281 | ntail = nbperpage; |
282 | nextend = ntail - xlen; |
283 | ninsert = nxlen - nbperpage; |
284 | |
285 | xflag = XAD_NOTRECORDED; |
286 | } else { |
287 | ntail = nxlen; |
288 | nextend = delta; |
289 | ninsert = 0; |
290 | |
291 | xflag = xp->flag; |
292 | } |
293 | |
294 | /* if we were able to extend the disk allocation in place, |
295 | * extend the extent. otherwise, move the extent to a |
296 | * new disk location. |
297 | */ |
298 | if (xaddr == nxaddr) { |
299 | /* extend the extent */ |
300 | if ((rc = xtExtend(0, ip, xoff + xlen, (int) nextend, 0))) { |
301 | dbFree(ip, xaddr + xlen, delta); |
302 | dquot_free_block(ip, nxlen); |
303 | goto exit; |
304 | } |
305 | } else { |
306 | /* |
307 | * move the extent to a new location: |
308 | * |
309 | * xtTailgate() accounts for relocated tail extent; |
310 | */ |
311 | if ((rc = xtTailgate(0, ip, xoff, (int) ntail, nxaddr, 0))) { |
312 | dbFree(ip, nxaddr, nxlen); |
313 | dquot_free_block(ip, nxlen); |
314 | goto exit; |
315 | } |
316 | } |
317 | |
318 | |
319 | /* check if we need to also insert a new extent */ |
320 | if (ninsert) { |
321 | /* perform the insert. if it fails, free the blocks |
322 | * to be inserted and make it appear that we only did |
323 | * the xtExtend() or xtTailgate() above. |
324 | */ |
325 | xaddr = nxaddr + ntail; |
326 | if (xtInsert (0, ip, xflag, xoff + ntail, (int) ninsert, |
327 | &xaddr, 0)) { |
328 | dbFree(ip, xaddr, (s64) ninsert); |
329 | delta = nextend; |
330 | nxlen = ntail; |
331 | xflag = 0; |
332 | } |
333 | } |
334 | |
335 | /* set the return results */ |
336 | XADaddress(xp, nxaddr); |
337 | XADlength(xp, nxlen); |
338 | XADoffset(xp, xoff); |
339 | xp->flag = xflag; |
340 | |
341 | mark_inode_dirty(ip); |
342 | exit: |
343 | mutex_unlock(&JFS_IP(ip)->commit_mutex); |
344 | return (rc); |
345 | } |
346 | #endif /* _NOTYET */ |
347 | |
348 | |
349 | /* |
350 | * NAME: extHint() |
351 | * |
352 | * FUNCTION: produce an extent allocation hint for a file offset. |
353 | * |
354 | * PARAMETERS: |
355 | * ip - the inode of the file. |
356 | * offset - file offset for which the hint is needed. |
357 | * xp - pointer to the xad that is to be filled in with |
358 | * the hint. |
359 | * |
360 | * RETURN VALUES: |
361 | * 0 - success |
362 | * -EIO - i/o error. |
363 | */ |
364 | int extHint(struct inode *ip, s64 offset, xad_t * xp) |
365 | { |
366 | struct super_block *sb = ip->i_sb; |
367 | int nbperpage = JFS_SBI(sb)->nbperpage; |
368 | s64 prev; |
369 | int rc = 0; |
370 | s64 xaddr; |
371 | int xlen; |
372 | int xflag; |
373 | |
374 | /* init the hint as "no hint provided" */ |
375 | XADaddress(xp, 0); |
376 | |
377 | /* determine the starting extent offset of the page previous |
378 | * to the page containing the offset. |
379 | */ |
380 | prev = ((offset & ~POFFSET) >> JFS_SBI(sb)->l2bsize) - nbperpage; |
381 | |
382 | /* if the offset is in the first page of the file, no hint provided. |
383 | */ |
384 | if (prev < 0) |
385 | goto out; |
386 | |
387 | rc = xtLookup(ip, prev, nbperpage, &xflag, &xaddr, &xlen, 0); |
388 | |
389 | if ((rc == 0) && xlen) { |
390 | if (xlen != nbperpage) { |
391 | jfs_error(ip->i_sb, "extHint: corrupt xtree"); |
392 | rc = -EIO; |
393 | } |
394 | XADaddress(xp, xaddr); |
395 | XADlength(xp, xlen); |
396 | XADoffset(xp, prev); |
397 | /* |
398 | * only preserve the abnr flag within the xad flags |
399 | * of the returned hint. |
400 | */ |
401 | xp->flag = xflag & XAD_NOTRECORDED; |
402 | } else |
403 | rc = 0; |
404 | |
405 | out: |
406 | return (rc); |
407 | } |
408 | |
409 | |
410 | /* |
411 | * NAME: extRecord() |
412 | * |
413 | * FUNCTION: change a page with a file from not recorded to recorded. |
414 | * |
415 | * PARAMETERS: |
416 | * ip - inode of the file. |
417 | * cp - cbuf of the file page. |
418 | * |
419 | * RETURN VALUES: |
420 | * 0 - success |
421 | * -EIO - i/o error. |
422 | * -ENOSPC - insufficient disk resources. |
423 | */ |
424 | int extRecord(struct inode *ip, xad_t * xp) |
425 | { |
426 | int rc; |
427 | |
428 | txBeginAnon(ip->i_sb); |
429 | |
430 | mutex_lock(&JFS_IP(ip)->commit_mutex); |
431 | |
432 | /* update the extent */ |
433 | rc = xtUpdate(0, ip, xp); |
434 | |
435 | mutex_unlock(&JFS_IP(ip)->commit_mutex); |
436 | return rc; |
437 | } |
438 | |
439 | |
440 | #ifdef _NOTYET |
441 | /* |
442 | * NAME: extFill() |
443 | * |
444 | * FUNCTION: allocate disk space for a file page that represents |
445 | * a file hole. |
446 | * |
447 | * PARAMETERS: |
448 | * ip - the inode of the file. |
449 | * cp - cbuf of the file page represent the hole. |
450 | * |
451 | * RETURN VALUES: |
452 | * 0 - success |
453 | * -EIO - i/o error. |
454 | * -ENOSPC - insufficient disk resources. |
455 | */ |
456 | int extFill(struct inode *ip, xad_t * xp) |
457 | { |
458 | int rc, nbperpage = JFS_SBI(ip->i_sb)->nbperpage; |
459 | s64 blkno = offsetXAD(xp) >> ip->i_blkbits; |
460 | |
461 | // assert(ISSPARSE(ip)); |
462 | |
463 | /* initialize the extent allocation hint */ |
464 | XADaddress(xp, 0); |
465 | |
466 | /* allocate an extent to fill the hole */ |
467 | if ((rc = extAlloc(ip, nbperpage, blkno, xp, false))) |
468 | return (rc); |
469 | |
470 | assert(lengthPXD(xp) == nbperpage); |
471 | |
472 | return (0); |
473 | } |
474 | #endif /* _NOTYET */ |
475 | |
476 | |
477 | /* |
478 | * NAME: extBalloc() |
479 | * |
480 | * FUNCTION: allocate disk blocks to form an extent. |
481 | * |
482 | * initially, we will try to allocate disk blocks for the |
483 | * requested size (nblocks). if this fails (nblocks |
484 | * contiguous free blocks not available), we'll try to allocate |
485 | * a smaller number of blocks (producing a smaller extent), with |
486 | * this smaller number of blocks consisting of the requested |
487 | * number of blocks rounded down to the next smaller power of 2 |
488 | * number (i.e. 16 -> 8). we'll continue to round down and |
489 | * retry the allocation until the number of blocks to allocate |
490 | * is smaller than the number of blocks per page. |
491 | * |
492 | * PARAMETERS: |
493 | * ip - the inode of the file. |
494 | * hint - disk block number to be used as an allocation hint. |
495 | * *nblocks - pointer to an s64 value. on entry, this value specifies |
496 | * the desired number of block to be allocated. on successful |
497 | * exit, this value is set to the number of blocks actually |
498 | * allocated. |
499 | * blkno - pointer to a block address that is filled in on successful |
500 | * return with the starting block number of the newly |
501 | * allocated block range. |
502 | * |
503 | * RETURN VALUES: |
504 | * 0 - success |
505 | * -EIO - i/o error. |
506 | * -ENOSPC - insufficient disk resources. |
507 | */ |
508 | static int |
509 | extBalloc(struct inode *ip, s64 hint, s64 * nblocks, s64 * blkno) |
510 | { |
511 | struct jfs_inode_info *ji = JFS_IP(ip); |
512 | struct jfs_sb_info *sbi = JFS_SBI(ip->i_sb); |
513 | s64 nb, nblks, daddr, max; |
514 | int rc, nbperpage = sbi->nbperpage; |
515 | struct bmap *bmp = sbi->bmap; |
516 | int ag; |
517 | |
518 | /* get the number of blocks to initially attempt to allocate. |
519 | * we'll first try the number of blocks requested unless this |
520 | * number is greater than the maximum number of contiguous free |
521 | * blocks in the map. in that case, we'll start off with the |
522 | * maximum free. |
523 | */ |
524 | max = (s64) 1 << bmp->db_maxfreebud; |
525 | if (*nblocks >= max && *nblocks > nbperpage) |
526 | nb = nblks = (max > nbperpage) ? max : nbperpage; |
527 | else |
528 | nb = nblks = *nblocks; |
529 | |
530 | /* try to allocate blocks */ |
531 | while ((rc = dbAlloc(ip, hint, nb, &daddr)) != 0) { |
532 | /* if something other than an out of space error, |
533 | * stop and return this error. |
534 | */ |
535 | if (rc != -ENOSPC) |
536 | return (rc); |
537 | |
538 | /* decrease the allocation request size */ |
539 | nb = min(nblks, extRoundDown(nb)); |
540 | |
541 | /* give up if we cannot cover a page */ |
542 | if (nb < nbperpage) |
543 | return (rc); |
544 | } |
545 | |
546 | *nblocks = nb; |
547 | *blkno = daddr; |
548 | |
549 | if (S_ISREG(ip->i_mode) && (ji->fileset == FILESYSTEM_I)) { |
550 | ag = BLKTOAG(daddr, sbi); |
551 | spin_lock_irq(&ji->ag_lock); |
552 | if (ji->active_ag == -1) { |
553 | atomic_inc(&bmp->db_active[ag]); |
554 | ji->active_ag = ag; |
555 | } else if (ji->active_ag != ag) { |
556 | atomic_dec(&bmp->db_active[ji->active_ag]); |
557 | atomic_inc(&bmp->db_active[ag]); |
558 | ji->active_ag = ag; |
559 | } |
560 | spin_unlock_irq(&ji->ag_lock); |
561 | } |
562 | |
563 | return (0); |
564 | } |
565 | |
566 | |
567 | #ifdef _NOTYET |
568 | /* |
569 | * NAME: extBrealloc() |
570 | * |
571 | * FUNCTION: attempt to extend an extent's allocation. |
572 | * |
573 | * Initially, we will try to extend the extent's allocation |
574 | * in place. If this fails, we'll try to move the extent |
575 | * to a new set of blocks. If moving the extent, we initially |
576 | * will try to allocate disk blocks for the requested size |
577 | * (newnblks). if this fails (new contiguous free blocks not |
578 | * available), we'll try to allocate a smaller number of |
579 | * blocks (producing a smaller extent), with this smaller |
580 | * number of blocks consisting of the requested number of |
581 | * blocks rounded down to the next smaller power of 2 |
582 | * number (i.e. 16 -> 8). We'll continue to round down and |
583 | * retry the allocation until the number of blocks to allocate |
584 | * is smaller than the number of blocks per page. |
585 | * |
586 | * PARAMETERS: |
587 | * ip - the inode of the file. |
588 | * blkno - starting block number of the extents current allocation. |
589 | * nblks - number of blocks within the extents current allocation. |
590 | * newnblks - pointer to a s64 value. on entry, this value is the |
591 | * the new desired extent size (number of blocks). on |
592 | * successful exit, this value is set to the extent's actual |
593 | * new size (new number of blocks). |
594 | * newblkno - the starting block number of the extents new allocation. |
595 | * |
596 | * RETURN VALUES: |
597 | * 0 - success |
598 | * -EIO - i/o error. |
599 | * -ENOSPC - insufficient disk resources. |
600 | */ |
601 | static int |
602 | extBrealloc(struct inode *ip, |
603 | s64 blkno, s64 nblks, s64 * newnblks, s64 * newblkno) |
604 | { |
605 | int rc; |
606 | |
607 | /* try to extend in place */ |
608 | if ((rc = dbExtend(ip, blkno, nblks, *newnblks - nblks)) == 0) { |
609 | *newblkno = blkno; |
610 | return (0); |
611 | } else { |
612 | if (rc != -ENOSPC) |
613 | return (rc); |
614 | } |
615 | |
616 | /* in place extension not possible. |
617 | * try to move the extent to a new set of blocks. |
618 | */ |
619 | return (extBalloc(ip, blkno, newnblks, newblkno)); |
620 | } |
621 | #endif /* _NOTYET */ |
622 | |
623 | |
624 | /* |
625 | * NAME: extRoundDown() |
626 | * |
627 | * FUNCTION: round down a specified number of blocks to the next |
628 | * smallest power of 2 number. |
629 | * |
630 | * PARAMETERS: |
631 | * nb - the inode of the file. |
632 | * |
633 | * RETURN VALUES: |
634 | * next smallest power of 2 number. |
635 | */ |
636 | static s64 extRoundDown(s64 nb) |
637 | { |
638 | int i; |
639 | u64 m, k; |
640 | |
641 | for (i = 0, m = (u64) 1 << 63; i < 64; i++, m >>= 1) { |
642 | if (m & nb) |
643 | break; |
644 | } |
645 | |
646 | i = 63 - i; |
647 | k = (u64) 1 << i; |
648 | k = ((k - 1) & nb) ? k : k >> 1; |
649 | |
650 | return (k); |
651 | } |
652 |
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javiroman/ks7010
jz-2.6.34
jz-2.6.34-rc5
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Tags:
od-2011-09-04
od-2011-09-18
v2.6.34-rc5
v2.6.34-rc6
v2.6.34-rc7
v3.9