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[XFS] Remove xfs_macros.c, xfs_macros.h, rework headers a whole lot.
[GitHub/mt8127/android_kernel_alcatel_ttab.git] / fs / xfs / xfs_alloc.c
1 /*
2 * Copyright (c) 2000-2002 Silicon Graphics, Inc. All Rights Reserved.
3 *
4 * This program is free software; you can redistribute it and/or modify it
5 * under the terms of version 2 of the GNU General Public License as
6 * published by the Free Software Foundation.
7 *
8 * This program is distributed in the hope that it would be useful, but
9 * WITHOUT ANY WARRANTY; without even the implied warranty of
10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
11 *
12 * Further, this software is distributed without any warranty that it is
13 * free of the rightful claim of any third person regarding infringement
14 * or the like. Any license provided herein, whether implied or
15 * otherwise, applies only to this software file. Patent licenses, if
16 * any, provided herein do not apply to combinations of this program with
17 * other software, or any other product whatsoever.
18 *
19 * You should have received a copy of the GNU General Public License along
20 * with this program; if not, write the Free Software Foundation, Inc., 59
21 * Temple Place - Suite 330, Boston MA 02111-1307, USA.
22 *
23 * Contact information: Silicon Graphics, Inc., 1600 Amphitheatre Pkwy,
24 * Mountain View, CA 94043, or:
25 *
26 * http://www.sgi.com
27 *
28 * For further information regarding this notice, see:
29 *
30 * http://oss.sgi.com/projects/GenInfo/SGIGPLNoticeExplan/
31 */
32 #include "xfs.h"
33 #include "xfs_fs.h"
34 #include "xfs_types.h"
35 #include "xfs_bit.h"
36 #include "xfs_log.h"
37 #include "xfs_inum.h"
38 #include "xfs_trans.h"
39 #include "xfs_sb.h"
40 #include "xfs_ag.h"
41 #include "xfs_dir.h"
42 #include "xfs_dir2.h"
43 #include "xfs_dmapi.h"
44 #include "xfs_mount.h"
45 #include "xfs_bmap_btree.h"
46 #include "xfs_alloc_btree.h"
47 #include "xfs_ialloc_btree.h"
48 #include "xfs_dir_sf.h"
49 #include "xfs_dir2_sf.h"
50 #include "xfs_attr_sf.h"
51 #include "xfs_dinode.h"
52 #include "xfs_inode.h"
53 #include "xfs_btree.h"
54 #include "xfs_ialloc.h"
55 #include "xfs_alloc.h"
56 #include "xfs_error.h"
57
58
59 #define XFS_ABSDIFF(a,b) (((a) <= (b)) ? ((b) - (a)) : ((a) - (b)))
60
61 #define XFSA_FIXUP_BNO_OK 1
62 #define XFSA_FIXUP_CNT_OK 2
63
64 STATIC int
65 xfs_alloc_search_busy(xfs_trans_t *tp,
66 xfs_agnumber_t agno,
67 xfs_agblock_t bno,
68 xfs_extlen_t len);
69
70 #if defined(XFS_ALLOC_TRACE)
71 ktrace_t *xfs_alloc_trace_buf;
72
73 #define TRACE_ALLOC(s,a) \
74 xfs_alloc_trace_alloc(fname, s, a, __LINE__)
75 #define TRACE_FREE(s,a,b,x,f) \
76 xfs_alloc_trace_free(fname, s, mp, a, b, x, f, __LINE__)
77 #define TRACE_MODAGF(s,a,f) \
78 xfs_alloc_trace_modagf(fname, s, mp, a, f, __LINE__)
79 #define TRACE_BUSY(fname,s,ag,agb,l,sl,tp) \
80 xfs_alloc_trace_busy(fname, s, mp, ag, agb, l, sl, tp, XFS_ALLOC_KTRACE_BUSY, __LINE__)
81 #define TRACE_UNBUSY(fname,s,ag,sl,tp) \
82 xfs_alloc_trace_busy(fname, s, mp, ag, -1, -1, sl, tp, XFS_ALLOC_KTRACE_UNBUSY, __LINE__)
83 #define TRACE_BUSYSEARCH(fname,s,ag,agb,l,sl,tp) \
84 xfs_alloc_trace_busy(fname, s, mp, ag, agb, l, sl, tp, XFS_ALLOC_KTRACE_BUSYSEARCH, __LINE__)
85 #else
86 #define TRACE_ALLOC(s,a)
87 #define TRACE_FREE(s,a,b,x,f)
88 #define TRACE_MODAGF(s,a,f)
89 #define TRACE_BUSY(s,a,ag,agb,l,sl,tp)
90 #define TRACE_UNBUSY(fname,s,ag,sl,tp)
91 #define TRACE_BUSYSEARCH(fname,s,ag,agb,l,sl,tp)
92 #endif /* XFS_ALLOC_TRACE */
93
94 /*
95 * Prototypes for per-ag allocation routines
96 */
97
98 STATIC int xfs_alloc_ag_vextent_exact(xfs_alloc_arg_t *);
99 STATIC int xfs_alloc_ag_vextent_near(xfs_alloc_arg_t *);
100 STATIC int xfs_alloc_ag_vextent_size(xfs_alloc_arg_t *);
101 STATIC int xfs_alloc_ag_vextent_small(xfs_alloc_arg_t *,
102 xfs_btree_cur_t *, xfs_agblock_t *, xfs_extlen_t *, int *);
103
104 /*
105 * Internal functions.
106 */
107
108 /*
109 * Compute aligned version of the found extent.
110 * Takes alignment and min length into account.
111 */
112 STATIC int /* success (>= minlen) */
113 xfs_alloc_compute_aligned(
114 xfs_agblock_t foundbno, /* starting block in found extent */
115 xfs_extlen_t foundlen, /* length in found extent */
116 xfs_extlen_t alignment, /* alignment for allocation */
117 xfs_extlen_t minlen, /* minimum length for allocation */
118 xfs_agblock_t *resbno, /* result block number */
119 xfs_extlen_t *reslen) /* result length */
120 {
121 xfs_agblock_t bno;
122 xfs_extlen_t diff;
123 xfs_extlen_t len;
124
125 if (alignment > 1 && foundlen >= minlen) {
126 bno = roundup(foundbno, alignment);
127 diff = bno - foundbno;
128 len = diff >= foundlen ? 0 : foundlen - diff;
129 } else {
130 bno = foundbno;
131 len = foundlen;
132 }
133 *resbno = bno;
134 *reslen = len;
135 return len >= minlen;
136 }
137
138 /*
139 * Compute best start block and diff for "near" allocations.
140 * freelen >= wantlen already checked by caller.
141 */
142 STATIC xfs_extlen_t /* difference value (absolute) */
143 xfs_alloc_compute_diff(
144 xfs_agblock_t wantbno, /* target starting block */
145 xfs_extlen_t wantlen, /* target length */
146 xfs_extlen_t alignment, /* target alignment */
147 xfs_agblock_t freebno, /* freespace's starting block */
148 xfs_extlen_t freelen, /* freespace's length */
149 xfs_agblock_t *newbnop) /* result: best start block from free */
150 {
151 xfs_agblock_t freeend; /* end of freespace extent */
152 xfs_agblock_t newbno1; /* return block number */
153 xfs_agblock_t newbno2; /* other new block number */
154 xfs_extlen_t newlen1=0; /* length with newbno1 */
155 xfs_extlen_t newlen2=0; /* length with newbno2 */
156 xfs_agblock_t wantend; /* end of target extent */
157
158 ASSERT(freelen >= wantlen);
159 freeend = freebno + freelen;
160 wantend = wantbno + wantlen;
161 if (freebno >= wantbno) {
162 if ((newbno1 = roundup(freebno, alignment)) >= freeend)
163 newbno1 = NULLAGBLOCK;
164 } else if (freeend >= wantend && alignment > 1) {
165 newbno1 = roundup(wantbno, alignment);
166 newbno2 = newbno1 - alignment;
167 if (newbno1 >= freeend)
168 newbno1 = NULLAGBLOCK;
169 else
170 newlen1 = XFS_EXTLEN_MIN(wantlen, freeend - newbno1);
171 if (newbno2 < freebno)
172 newbno2 = NULLAGBLOCK;
173 else
174 newlen2 = XFS_EXTLEN_MIN(wantlen, freeend - newbno2);
175 if (newbno1 != NULLAGBLOCK && newbno2 != NULLAGBLOCK) {
176 if (newlen1 < newlen2 ||
177 (newlen1 == newlen2 &&
178 XFS_ABSDIFF(newbno1, wantbno) >
179 XFS_ABSDIFF(newbno2, wantbno)))
180 newbno1 = newbno2;
181 } else if (newbno2 != NULLAGBLOCK)
182 newbno1 = newbno2;
183 } else if (freeend >= wantend) {
184 newbno1 = wantbno;
185 } else if (alignment > 1) {
186 newbno1 = roundup(freeend - wantlen, alignment);
187 if (newbno1 > freeend - wantlen &&
188 newbno1 - alignment >= freebno)
189 newbno1 -= alignment;
190 else if (newbno1 >= freeend)
191 newbno1 = NULLAGBLOCK;
192 } else
193 newbno1 = freeend - wantlen;
194 *newbnop = newbno1;
195 return newbno1 == NULLAGBLOCK ? 0 : XFS_ABSDIFF(newbno1, wantbno);
196 }
197
198 /*
199 * Fix up the length, based on mod and prod.
200 * len should be k * prod + mod for some k.
201 * If len is too small it is returned unchanged.
202 * If len hits maxlen it is left alone.
203 */
204 STATIC void
205 xfs_alloc_fix_len(
206 xfs_alloc_arg_t *args) /* allocation argument structure */
207 {
208 xfs_extlen_t k;
209 xfs_extlen_t rlen;
210
211 ASSERT(args->mod < args->prod);
212 rlen = args->len;
213 ASSERT(rlen >= args->minlen);
214 ASSERT(rlen <= args->maxlen);
215 if (args->prod <= 1 || rlen < args->mod || rlen == args->maxlen ||
216 (args->mod == 0 && rlen < args->prod))
217 return;
218 k = rlen % args->prod;
219 if (k == args->mod)
220 return;
221 if (k > args->mod) {
222 if ((int)(rlen = rlen - k - args->mod) < (int)args->minlen)
223 return;
224 } else {
225 if ((int)(rlen = rlen - args->prod - (args->mod - k)) <
226 (int)args->minlen)
227 return;
228 }
229 ASSERT(rlen >= args->minlen);
230 ASSERT(rlen <= args->maxlen);
231 args->len = rlen;
232 }
233
234 /*
235 * Fix up length if there is too little space left in the a.g.
236 * Return 1 if ok, 0 if too little, should give up.
237 */
238 STATIC int
239 xfs_alloc_fix_minleft(
240 xfs_alloc_arg_t *args) /* allocation argument structure */
241 {
242 xfs_agf_t *agf; /* a.g. freelist header */
243 int diff; /* free space difference */
244
245 if (args->minleft == 0)
246 return 1;
247 agf = XFS_BUF_TO_AGF(args->agbp);
248 diff = INT_GET(agf->agf_freeblks, ARCH_CONVERT)
249 + INT_GET(agf->agf_flcount, ARCH_CONVERT)
250 - args->len - args->minleft;
251 if (diff >= 0)
252 return 1;
253 args->len += diff; /* shrink the allocated space */
254 if (args->len >= args->minlen)
255 return 1;
256 args->agbno = NULLAGBLOCK;
257 return 0;
258 }
259
260 /*
261 * Update the two btrees, logically removing from freespace the extent
262 * starting at rbno, rlen blocks. The extent is contained within the
263 * actual (current) free extent fbno for flen blocks.
264 * Flags are passed in indicating whether the cursors are set to the
265 * relevant records.
266 */
267 STATIC int /* error code */
268 xfs_alloc_fixup_trees(
269 xfs_btree_cur_t *cnt_cur, /* cursor for by-size btree */
270 xfs_btree_cur_t *bno_cur, /* cursor for by-block btree */
271 xfs_agblock_t fbno, /* starting block of free extent */
272 xfs_extlen_t flen, /* length of free extent */
273 xfs_agblock_t rbno, /* starting block of returned extent */
274 xfs_extlen_t rlen, /* length of returned extent */
275 int flags) /* flags, XFSA_FIXUP_... */
276 {
277 int error; /* error code */
278 int i; /* operation results */
279 xfs_agblock_t nfbno1; /* first new free startblock */
280 xfs_agblock_t nfbno2; /* second new free startblock */
281 xfs_extlen_t nflen1=0; /* first new free length */
282 xfs_extlen_t nflen2=0; /* second new free length */
283
284 /*
285 * Look up the record in the by-size tree if necessary.
286 */
287 if (flags & XFSA_FIXUP_CNT_OK) {
288 #ifdef DEBUG
289 if ((error = xfs_alloc_get_rec(cnt_cur, &nfbno1, &nflen1, &i)))
290 return error;
291 XFS_WANT_CORRUPTED_RETURN(
292 i == 1 && nfbno1 == fbno && nflen1 == flen);
293 #endif
294 } else {
295 if ((error = xfs_alloc_lookup_eq(cnt_cur, fbno, flen, &i)))
296 return error;
297 XFS_WANT_CORRUPTED_RETURN(i == 1);
298 }
299 /*
300 * Look up the record in the by-block tree if necessary.
301 */
302 if (flags & XFSA_FIXUP_BNO_OK) {
303 #ifdef DEBUG
304 if ((error = xfs_alloc_get_rec(bno_cur, &nfbno1, &nflen1, &i)))
305 return error;
306 XFS_WANT_CORRUPTED_RETURN(
307 i == 1 && nfbno1 == fbno && nflen1 == flen);
308 #endif
309 } else {
310 if ((error = xfs_alloc_lookup_eq(bno_cur, fbno, flen, &i)))
311 return error;
312 XFS_WANT_CORRUPTED_RETURN(i == 1);
313 }
314 #ifdef DEBUG
315 {
316 xfs_alloc_block_t *bnoblock;
317 xfs_alloc_block_t *cntblock;
318
319 if (bno_cur->bc_nlevels == 1 &&
320 cnt_cur->bc_nlevels == 1) {
321 bnoblock = XFS_BUF_TO_ALLOC_BLOCK(bno_cur->bc_bufs[0]);
322 cntblock = XFS_BUF_TO_ALLOC_BLOCK(cnt_cur->bc_bufs[0]);
323 XFS_WANT_CORRUPTED_RETURN(
324 INT_GET(bnoblock->bb_numrecs, ARCH_CONVERT) == INT_GET(cntblock->bb_numrecs, ARCH_CONVERT));
325 }
326 }
327 #endif
328 /*
329 * Deal with all four cases: the allocated record is contained
330 * within the freespace record, so we can have new freespace
331 * at either (or both) end, or no freespace remaining.
332 */
333 if (rbno == fbno && rlen == flen)
334 nfbno1 = nfbno2 = NULLAGBLOCK;
335 else if (rbno == fbno) {
336 nfbno1 = rbno + rlen;
337 nflen1 = flen - rlen;
338 nfbno2 = NULLAGBLOCK;
339 } else if (rbno + rlen == fbno + flen) {
340 nfbno1 = fbno;
341 nflen1 = flen - rlen;
342 nfbno2 = NULLAGBLOCK;
343 } else {
344 nfbno1 = fbno;
345 nflen1 = rbno - fbno;
346 nfbno2 = rbno + rlen;
347 nflen2 = (fbno + flen) - nfbno2;
348 }
349 /*
350 * Delete the entry from the by-size btree.
351 */
352 if ((error = xfs_alloc_delete(cnt_cur, &i)))
353 return error;
354 XFS_WANT_CORRUPTED_RETURN(i == 1);
355 /*
356 * Add new by-size btree entry(s).
357 */
358 if (nfbno1 != NULLAGBLOCK) {
359 if ((error = xfs_alloc_lookup_eq(cnt_cur, nfbno1, nflen1, &i)))
360 return error;
361 XFS_WANT_CORRUPTED_RETURN(i == 0);
362 if ((error = xfs_alloc_insert(cnt_cur, &i)))
363 return error;
364 XFS_WANT_CORRUPTED_RETURN(i == 1);
365 }
366 if (nfbno2 != NULLAGBLOCK) {
367 if ((error = xfs_alloc_lookup_eq(cnt_cur, nfbno2, nflen2, &i)))
368 return error;
369 XFS_WANT_CORRUPTED_RETURN(i == 0);
370 if ((error = xfs_alloc_insert(cnt_cur, &i)))
371 return error;
372 XFS_WANT_CORRUPTED_RETURN(i == 1);
373 }
374 /*
375 * Fix up the by-block btree entry(s).
376 */
377 if (nfbno1 == NULLAGBLOCK) {
378 /*
379 * No remaining freespace, just delete the by-block tree entry.
380 */
381 if ((error = xfs_alloc_delete(bno_cur, &i)))
382 return error;
383 XFS_WANT_CORRUPTED_RETURN(i == 1);
384 } else {
385 /*
386 * Update the by-block entry to start later|be shorter.
387 */
388 if ((error = xfs_alloc_update(bno_cur, nfbno1, nflen1)))
389 return error;
390 }
391 if (nfbno2 != NULLAGBLOCK) {
392 /*
393 * 2 resulting free entries, need to add one.
394 */
395 if ((error = xfs_alloc_lookup_eq(bno_cur, nfbno2, nflen2, &i)))
396 return error;
397 XFS_WANT_CORRUPTED_RETURN(i == 0);
398 if ((error = xfs_alloc_insert(bno_cur, &i)))
399 return error;
400 XFS_WANT_CORRUPTED_RETURN(i == 1);
401 }
402 return 0;
403 }
404
405 /*
406 * Read in the allocation group free block array.
407 */
408 STATIC int /* error */
409 xfs_alloc_read_agfl(
410 xfs_mount_t *mp, /* mount point structure */
411 xfs_trans_t *tp, /* transaction pointer */
412 xfs_agnumber_t agno, /* allocation group number */
413 xfs_buf_t **bpp) /* buffer for the ag free block array */
414 {
415 xfs_buf_t *bp; /* return value */
416 int error;
417
418 ASSERT(agno != NULLAGNUMBER);
419 error = xfs_trans_read_buf(
420 mp, tp, mp->m_ddev_targp,
421 XFS_AG_DADDR(mp, agno, XFS_AGFL_DADDR(mp)),
422 XFS_FSS_TO_BB(mp, 1), 0, &bp);
423 if (error)
424 return error;
425 ASSERT(bp);
426 ASSERT(!XFS_BUF_GETERROR(bp));
427 XFS_BUF_SET_VTYPE_REF(bp, B_FS_AGFL, XFS_AGFL_REF);
428 *bpp = bp;
429 return 0;
430 }
431
432 #if defined(XFS_ALLOC_TRACE)
433 /*
434 * Add an allocation trace entry for an alloc call.
435 */
436 STATIC void
437 xfs_alloc_trace_alloc(
438 char *name, /* function tag string */
439 char *str, /* additional string */
440 xfs_alloc_arg_t *args, /* allocation argument structure */
441 int line) /* source line number */
442 {
443 ktrace_enter(xfs_alloc_trace_buf,
444 (void *)(__psint_t)(XFS_ALLOC_KTRACE_ALLOC | (line << 16)),
445 (void *)name,
446 (void *)str,
447 (void *)args->mp,
448 (void *)(__psunsigned_t)args->agno,
449 (void *)(__psunsigned_t)args->agbno,
450 (void *)(__psunsigned_t)args->minlen,
451 (void *)(__psunsigned_t)args->maxlen,
452 (void *)(__psunsigned_t)args->mod,
453 (void *)(__psunsigned_t)args->prod,
454 (void *)(__psunsigned_t)args->minleft,
455 (void *)(__psunsigned_t)args->total,
456 (void *)(__psunsigned_t)args->alignment,
457 (void *)(__psunsigned_t)args->len,
458 (void *)((((__psint_t)args->type) << 16) |
459 (__psint_t)args->otype),
460 (void *)(__psint_t)((args->wasdel << 3) |
461 (args->wasfromfl << 2) |
462 (args->isfl << 1) |
463 (args->userdata << 0)));
464 }
465
466 /*
467 * Add an allocation trace entry for a free call.
468 */
469 STATIC void
470 xfs_alloc_trace_free(
471 char *name, /* function tag string */
472 char *str, /* additional string */
473 xfs_mount_t *mp, /* file system mount point */
474 xfs_agnumber_t agno, /* allocation group number */
475 xfs_agblock_t agbno, /* a.g. relative block number */
476 xfs_extlen_t len, /* length of extent */
477 int isfl, /* set if is freelist allocation/free */
478 int line) /* source line number */
479 {
480 ktrace_enter(xfs_alloc_trace_buf,
481 (void *)(__psint_t)(XFS_ALLOC_KTRACE_FREE | (line << 16)),
482 (void *)name,
483 (void *)str,
484 (void *)mp,
485 (void *)(__psunsigned_t)agno,
486 (void *)(__psunsigned_t)agbno,
487 (void *)(__psunsigned_t)len,
488 (void *)(__psint_t)isfl,
489 NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL);
490 }
491
492 /*
493 * Add an allocation trace entry for modifying an agf.
494 */
495 STATIC void
496 xfs_alloc_trace_modagf(
497 char *name, /* function tag string */
498 char *str, /* additional string */
499 xfs_mount_t *mp, /* file system mount point */
500 xfs_agf_t *agf, /* new agf value */
501 int flags, /* logging flags for agf */
502 int line) /* source line number */
503 {
504 ktrace_enter(xfs_alloc_trace_buf,
505 (void *)(__psint_t)(XFS_ALLOC_KTRACE_MODAGF | (line << 16)),
506 (void *)name,
507 (void *)str,
508 (void *)mp,
509 (void *)(__psint_t)flags,
510 (void *)(__psunsigned_t)INT_GET(agf->agf_seqno, ARCH_CONVERT),
511 (void *)(__psunsigned_t)INT_GET(agf->agf_length, ARCH_CONVERT),
512 (void *)(__psunsigned_t)INT_GET(agf->agf_roots[XFS_BTNUM_BNO],
513 ARCH_CONVERT),
514 (void *)(__psunsigned_t)INT_GET(agf->agf_roots[XFS_BTNUM_CNT],
515 ARCH_CONVERT),
516 (void *)(__psunsigned_t)INT_GET(agf->agf_levels[XFS_BTNUM_BNO],
517 ARCH_CONVERT),
518 (void *)(__psunsigned_t)INT_GET(agf->agf_levels[XFS_BTNUM_CNT],
519 ARCH_CONVERT),
520 (void *)(__psunsigned_t)INT_GET(agf->agf_flfirst, ARCH_CONVERT),
521 (void *)(__psunsigned_t)INT_GET(agf->agf_fllast, ARCH_CONVERT),
522 (void *)(__psunsigned_t)INT_GET(agf->agf_flcount, ARCH_CONVERT),
523 (void *)(__psunsigned_t)INT_GET(agf->agf_freeblks, ARCH_CONVERT),
524 (void *)(__psunsigned_t)INT_GET(agf->agf_longest, ARCH_CONVERT));
525 }
526
527 STATIC void
528 xfs_alloc_trace_busy(
529 char *name, /* function tag string */
530 char *str, /* additional string */
531 xfs_mount_t *mp, /* file system mount poing */
532 xfs_agnumber_t agno, /* allocation group number */
533 xfs_agblock_t agbno, /* a.g. relative block number */
534 xfs_extlen_t len, /* length of extent */
535 int slot, /* perag Busy slot */
536 xfs_trans_t *tp,
537 int trtype, /* type: add, delete, search */
538 int line) /* source line number */
539 {
540 ktrace_enter(xfs_alloc_trace_buf,
541 (void *)(__psint_t)(trtype | (line << 16)),
542 (void *)name,
543 (void *)str,
544 (void *)mp,
545 (void *)(__psunsigned_t)agno,
546 (void *)(__psunsigned_t)agbno,
547 (void *)(__psunsigned_t)len,
548 (void *)(__psint_t)slot,
549 (void *)tp,
550 NULL, NULL, NULL, NULL, NULL, NULL, NULL);
551 }
552 #endif /* XFS_ALLOC_TRACE */
553
554 /*
555 * Allocation group level functions.
556 */
557
558 /*
559 * Allocate a variable extent in the allocation group agno.
560 * Type and bno are used to determine where in the allocation group the
561 * extent will start.
562 * Extent's length (returned in *len) will be between minlen and maxlen,
563 * and of the form k * prod + mod unless there's nothing that large.
564 * Return the starting a.g. block, or NULLAGBLOCK if we can't do it.
565 */
566 STATIC int /* error */
567 xfs_alloc_ag_vextent(
568 xfs_alloc_arg_t *args) /* argument structure for allocation */
569 {
570 int error=0;
571 #ifdef XFS_ALLOC_TRACE
572 static char fname[] = "xfs_alloc_ag_vextent";
573 #endif
574
575 ASSERT(args->minlen > 0);
576 ASSERT(args->maxlen > 0);
577 ASSERT(args->minlen <= args->maxlen);
578 ASSERT(args->mod < args->prod);
579 ASSERT(args->alignment > 0);
580 /*
581 * Branch to correct routine based on the type.
582 */
583 args->wasfromfl = 0;
584 switch (args->type) {
585 case XFS_ALLOCTYPE_THIS_AG:
586 error = xfs_alloc_ag_vextent_size(args);
587 break;
588 case XFS_ALLOCTYPE_NEAR_BNO:
589 error = xfs_alloc_ag_vextent_near(args);
590 break;
591 case XFS_ALLOCTYPE_THIS_BNO:
592 error = xfs_alloc_ag_vextent_exact(args);
593 break;
594 default:
595 ASSERT(0);
596 /* NOTREACHED */
597 }
598 if (error)
599 return error;
600 /*
601 * If the allocation worked, need to change the agf structure
602 * (and log it), and the superblock.
603 */
604 if (args->agbno != NULLAGBLOCK) {
605 xfs_agf_t *agf; /* allocation group freelist header */
606 #ifdef XFS_ALLOC_TRACE
607 xfs_mount_t *mp = args->mp;
608 #endif
609 long slen = (long)args->len;
610
611 ASSERT(args->len >= args->minlen && args->len <= args->maxlen);
612 ASSERT(!(args->wasfromfl) || !args->isfl);
613 ASSERT(args->agbno % args->alignment == 0);
614 if (!(args->wasfromfl)) {
615
616 agf = XFS_BUF_TO_AGF(args->agbp);
617 INT_MOD(agf->agf_freeblks, ARCH_CONVERT, -(args->len));
618 xfs_trans_agblocks_delta(args->tp,
619 -((long)(args->len)));
620 args->pag->pagf_freeblks -= args->len;
621 ASSERT(INT_GET(agf->agf_freeblks, ARCH_CONVERT)
622 <= INT_GET(agf->agf_length, ARCH_CONVERT));
623 TRACE_MODAGF(NULL, agf, XFS_AGF_FREEBLKS);
624 xfs_alloc_log_agf(args->tp, args->agbp,
625 XFS_AGF_FREEBLKS);
626 /* search the busylist for these blocks */
627 xfs_alloc_search_busy(args->tp, args->agno,
628 args->agbno, args->len);
629 }
630 if (!args->isfl)
631 xfs_trans_mod_sb(args->tp,
632 args->wasdel ? XFS_TRANS_SB_RES_FDBLOCKS :
633 XFS_TRANS_SB_FDBLOCKS, -slen);
634 XFS_STATS_INC(xs_allocx);
635 XFS_STATS_ADD(xs_allocb, args->len);
636 }
637 return 0;
638 }
639
640 /*
641 * Allocate a variable extent at exactly agno/bno.
642 * Extent's length (returned in *len) will be between minlen and maxlen,
643 * and of the form k * prod + mod unless there's nothing that large.
644 * Return the starting a.g. block (bno), or NULLAGBLOCK if we can't do it.
645 */
646 STATIC int /* error */
647 xfs_alloc_ag_vextent_exact(
648 xfs_alloc_arg_t *args) /* allocation argument structure */
649 {
650 xfs_btree_cur_t *bno_cur;/* by block-number btree cursor */
651 xfs_btree_cur_t *cnt_cur;/* by count btree cursor */
652 xfs_agblock_t end; /* end of allocated extent */
653 int error;
654 xfs_agblock_t fbno; /* start block of found extent */
655 xfs_agblock_t fend; /* end block of found extent */
656 xfs_extlen_t flen; /* length of found extent */
657 #ifdef XFS_ALLOC_TRACE
658 static char fname[] = "xfs_alloc_ag_vextent_exact";
659 #endif
660 int i; /* success/failure of operation */
661 xfs_agblock_t maxend; /* end of maximal extent */
662 xfs_agblock_t minend; /* end of minimal extent */
663 xfs_extlen_t rlen; /* length of returned extent */
664
665 ASSERT(args->alignment == 1);
666 /*
667 * Allocate/initialize a cursor for the by-number freespace btree.
668 */
669 bno_cur = xfs_btree_init_cursor(args->mp, args->tp, args->agbp,
670 args->agno, XFS_BTNUM_BNO, NULL, 0);
671 /*
672 * Lookup bno and minlen in the btree (minlen is irrelevant, really).
673 * Look for the closest free block <= bno, it must contain bno
674 * if any free block does.
675 */
676 if ((error = xfs_alloc_lookup_le(bno_cur, args->agbno, args->minlen, &i)))
677 goto error0;
678 if (!i) {
679 /*
680 * Didn't find it, return null.
681 */
682 xfs_btree_del_cursor(bno_cur, XFS_BTREE_NOERROR);
683 args->agbno = NULLAGBLOCK;
684 return 0;
685 }
686 /*
687 * Grab the freespace record.
688 */
689 if ((error = xfs_alloc_get_rec(bno_cur, &fbno, &flen, &i)))
690 goto error0;
691 XFS_WANT_CORRUPTED_GOTO(i == 1, error0);
692 ASSERT(fbno <= args->agbno);
693 minend = args->agbno + args->minlen;
694 maxend = args->agbno + args->maxlen;
695 fend = fbno + flen;
696 /*
697 * Give up if the freespace isn't long enough for the minimum request.
698 */
699 if (fend < minend) {
700 xfs_btree_del_cursor(bno_cur, XFS_BTREE_NOERROR);
701 args->agbno = NULLAGBLOCK;
702 return 0;
703 }
704 /*
705 * End of extent will be smaller of the freespace end and the
706 * maximal requested end.
707 */
708 end = XFS_AGBLOCK_MIN(fend, maxend);
709 /*
710 * Fix the length according to mod and prod if given.
711 */
712 args->len = end - args->agbno;
713 xfs_alloc_fix_len(args);
714 if (!xfs_alloc_fix_minleft(args)) {
715 xfs_btree_del_cursor(bno_cur, XFS_BTREE_NOERROR);
716 return 0;
717 }
718 rlen = args->len;
719 ASSERT(args->agbno + rlen <= fend);
720 end = args->agbno + rlen;
721 /*
722 * We are allocating agbno for rlen [agbno .. end]
723 * Allocate/initialize a cursor for the by-size btree.
724 */
725 cnt_cur = xfs_btree_init_cursor(args->mp, args->tp, args->agbp,
726 args->agno, XFS_BTNUM_CNT, NULL, 0);
727 ASSERT(args->agbno + args->len <=
728 INT_GET(XFS_BUF_TO_AGF(args->agbp)->agf_length,
729 ARCH_CONVERT));
730 if ((error = xfs_alloc_fixup_trees(cnt_cur, bno_cur, fbno, flen,
731 args->agbno, args->len, XFSA_FIXUP_BNO_OK))) {
732 xfs_btree_del_cursor(cnt_cur, XFS_BTREE_ERROR);
733 goto error0;
734 }
735 xfs_btree_del_cursor(bno_cur, XFS_BTREE_NOERROR);
736 xfs_btree_del_cursor(cnt_cur, XFS_BTREE_NOERROR);
737 TRACE_ALLOC("normal", args);
738 args->wasfromfl = 0;
739 return 0;
740
741 error0:
742 xfs_btree_del_cursor(bno_cur, XFS_BTREE_ERROR);
743 TRACE_ALLOC("error", args);
744 return error;
745 }
746
747 /*
748 * Allocate a variable extent near bno in the allocation group agno.
749 * Extent's length (returned in len) will be between minlen and maxlen,
750 * and of the form k * prod + mod unless there's nothing that large.
751 * Return the starting a.g. block, or NULLAGBLOCK if we can't do it.
752 */
753 STATIC int /* error */
754 xfs_alloc_ag_vextent_near(
755 xfs_alloc_arg_t *args) /* allocation argument structure */
756 {
757 xfs_btree_cur_t *bno_cur_gt; /* cursor for bno btree, right side */
758 xfs_btree_cur_t *bno_cur_lt; /* cursor for bno btree, left side */
759 xfs_btree_cur_t *cnt_cur; /* cursor for count btree */
760 #ifdef XFS_ALLOC_TRACE
761 static char fname[] = "xfs_alloc_ag_vextent_near";
762 #endif
763 xfs_agblock_t gtbno; /* start bno of right side entry */
764 xfs_agblock_t gtbnoa; /* aligned ... */
765 xfs_extlen_t gtdiff; /* difference to right side entry */
766 xfs_extlen_t gtlen; /* length of right side entry */
767 xfs_extlen_t gtlena; /* aligned ... */
768 xfs_agblock_t gtnew; /* useful start bno of right side */
769 int error; /* error code */
770 int i; /* result code, temporary */
771 int j; /* result code, temporary */
772 xfs_agblock_t ltbno; /* start bno of left side entry */
773 xfs_agblock_t ltbnoa; /* aligned ... */
774 xfs_extlen_t ltdiff; /* difference to left side entry */
775 /*REFERENCED*/
776 xfs_agblock_t ltend; /* end bno of left side entry */
777 xfs_extlen_t ltlen; /* length of left side entry */
778 xfs_extlen_t ltlena; /* aligned ... */
779 xfs_agblock_t ltnew; /* useful start bno of left side */
780 xfs_extlen_t rlen; /* length of returned extent */
781 #if defined(DEBUG) && defined(__KERNEL__)
782 /*
783 * Randomly don't execute the first algorithm.
784 */
785 int dofirst; /* set to do first algorithm */
786
787 dofirst = random() & 1;
788 #endif
789 /*
790 * Get a cursor for the by-size btree.
791 */
792 cnt_cur = xfs_btree_init_cursor(args->mp, args->tp, args->agbp,
793 args->agno, XFS_BTNUM_CNT, NULL, 0);
794 ltlen = 0;
795 bno_cur_lt = bno_cur_gt = NULL;
796 /*
797 * See if there are any free extents as big as maxlen.
798 */
799 if ((error = xfs_alloc_lookup_ge(cnt_cur, 0, args->maxlen, &i)))
800 goto error0;
801 /*
802 * If none, then pick up the last entry in the tree unless the
803 * tree is empty.
804 */
805 if (!i) {
806 if ((error = xfs_alloc_ag_vextent_small(args, cnt_cur, &ltbno,
807 &ltlen, &i)))
808 goto error0;
809 if (i == 0 || ltlen == 0) {
810 xfs_btree_del_cursor(cnt_cur, XFS_BTREE_NOERROR);
811 return 0;
812 }
813 ASSERT(i == 1);
814 }
815 args->wasfromfl = 0;
816 /*
817 * First algorithm.
818 * If the requested extent is large wrt the freespaces available
819 * in this a.g., then the cursor will be pointing to a btree entry
820 * near the right edge of the tree. If it's in the last btree leaf
821 * block, then we just examine all the entries in that block
822 * that are big enough, and pick the best one.
823 * This is written as a while loop so we can break out of it,
824 * but we never loop back to the top.
825 */
826 while (xfs_btree_islastblock(cnt_cur, 0)) {
827 xfs_extlen_t bdiff;
828 int besti=0;
829 xfs_extlen_t blen=0;
830 xfs_agblock_t bnew=0;
831
832 #if defined(DEBUG) && defined(__KERNEL__)
833 if (!dofirst)
834 break;
835 #endif
836 /*
837 * Start from the entry that lookup found, sequence through
838 * all larger free blocks. If we're actually pointing at a
839 * record smaller than maxlen, go to the start of this block,
840 * and skip all those smaller than minlen.
841 */
842 if (ltlen || args->alignment > 1) {
843 cnt_cur->bc_ptrs[0] = 1;
844 do {
845 if ((error = xfs_alloc_get_rec(cnt_cur, &ltbno,
846 &ltlen, &i)))
847 goto error0;
848 XFS_WANT_CORRUPTED_GOTO(i == 1, error0);
849 if (ltlen >= args->minlen)
850 break;
851 if ((error = xfs_alloc_increment(cnt_cur, 0, &i)))
852 goto error0;
853 } while (i);
854 ASSERT(ltlen >= args->minlen);
855 if (!i)
856 break;
857 }
858 i = cnt_cur->bc_ptrs[0];
859 for (j = 1, blen = 0, bdiff = 0;
860 !error && j && (blen < args->maxlen || bdiff > 0);
861 error = xfs_alloc_increment(cnt_cur, 0, &j)) {
862 /*
863 * For each entry, decide if it's better than
864 * the previous best entry.
865 */
866 if ((error = xfs_alloc_get_rec(cnt_cur, &ltbno, &ltlen, &i)))
867 goto error0;
868 XFS_WANT_CORRUPTED_GOTO(i == 1, error0);
869 if (!xfs_alloc_compute_aligned(ltbno, ltlen,
870 args->alignment, args->minlen,
871 &ltbnoa, &ltlena))
872 continue;
873 args->len = XFS_EXTLEN_MIN(ltlena, args->maxlen);
874 xfs_alloc_fix_len(args);
875 ASSERT(args->len >= args->minlen);
876 if (args->len < blen)
877 continue;
878 ltdiff = xfs_alloc_compute_diff(args->agbno, args->len,
879 args->alignment, ltbno, ltlen, &ltnew);
880 if (ltnew != NULLAGBLOCK &&
881 (args->len > blen || ltdiff < bdiff)) {
882 bdiff = ltdiff;
883 bnew = ltnew;
884 blen = args->len;
885 besti = cnt_cur->bc_ptrs[0];
886 }
887 }
888 /*
889 * It didn't work. We COULD be in a case where
890 * there's a good record somewhere, so try again.
891 */
892 if (blen == 0)
893 break;
894 /*
895 * Point at the best entry, and retrieve it again.
896 */
897 cnt_cur->bc_ptrs[0] = besti;
898 if ((error = xfs_alloc_get_rec(cnt_cur, &ltbno, &ltlen, &i)))
899 goto error0;
900 XFS_WANT_CORRUPTED_GOTO(i == 1, error0);
901 ltend = ltbno + ltlen;
902 ASSERT(ltend <= INT_GET(XFS_BUF_TO_AGF(args->agbp)->agf_length,
903 ARCH_CONVERT));
904 args->len = blen;
905 if (!xfs_alloc_fix_minleft(args)) {
906 xfs_btree_del_cursor(cnt_cur, XFS_BTREE_NOERROR);
907 TRACE_ALLOC("nominleft", args);
908 return 0;
909 }
910 blen = args->len;
911 /*
912 * We are allocating starting at bnew for blen blocks.
913 */
914 args->agbno = bnew;
915 ASSERT(bnew >= ltbno);
916 ASSERT(bnew + blen <= ltend);
917 /*
918 * Set up a cursor for the by-bno tree.
919 */
920 bno_cur_lt = xfs_btree_init_cursor(args->mp, args->tp,
921 args->agbp, args->agno, XFS_BTNUM_BNO, NULL, 0);
922 /*
923 * Fix up the btree entries.
924 */
925 if ((error = xfs_alloc_fixup_trees(cnt_cur, bno_cur_lt, ltbno,
926 ltlen, bnew, blen, XFSA_FIXUP_CNT_OK)))
927 goto error0;
928 xfs_btree_del_cursor(cnt_cur, XFS_BTREE_NOERROR);
929 xfs_btree_del_cursor(bno_cur_lt, XFS_BTREE_NOERROR);
930 TRACE_ALLOC("first", args);
931 return 0;
932 }
933 /*
934 * Second algorithm.
935 * Search in the by-bno tree to the left and to the right
936 * simultaneously, until in each case we find a space big enough,
937 * or run into the edge of the tree. When we run into the edge,
938 * we deallocate that cursor.
939 * If both searches succeed, we compare the two spaces and pick
940 * the better one.
941 * With alignment, it's possible for both to fail; the upper
942 * level algorithm that picks allocation groups for allocations
943 * is not supposed to do this.
944 */
945 /*
946 * Allocate and initialize the cursor for the leftward search.
947 */
948 bno_cur_lt = xfs_btree_init_cursor(args->mp, args->tp, args->agbp,
949 args->agno, XFS_BTNUM_BNO, NULL, 0);
950 /*
951 * Lookup <= bno to find the leftward search's starting point.
952 */
953 if ((error = xfs_alloc_lookup_le(bno_cur_lt, args->agbno, args->maxlen, &i)))
954 goto error0;
955 if (!i) {
956 /*
957 * Didn't find anything; use this cursor for the rightward
958 * search.
959 */
960 bno_cur_gt = bno_cur_lt;
961 bno_cur_lt = NULL;
962 }
963 /*
964 * Found something. Duplicate the cursor for the rightward search.
965 */
966 else if ((error = xfs_btree_dup_cursor(bno_cur_lt, &bno_cur_gt)))
967 goto error0;
968 /*
969 * Increment the cursor, so we will point at the entry just right
970 * of the leftward entry if any, or to the leftmost entry.
971 */
972 if ((error = xfs_alloc_increment(bno_cur_gt, 0, &i)))
973 goto error0;
974 if (!i) {
975 /*
976 * It failed, there are no rightward entries.
977 */
978 xfs_btree_del_cursor(bno_cur_gt, XFS_BTREE_NOERROR);
979 bno_cur_gt = NULL;
980 }
981 /*
982 * Loop going left with the leftward cursor, right with the
983 * rightward cursor, until either both directions give up or
984 * we find an entry at least as big as minlen.
985 */
986 do {
987 if (bno_cur_lt) {
988 if ((error = xfs_alloc_get_rec(bno_cur_lt, &ltbno, &ltlen, &i)))
989 goto error0;
990 XFS_WANT_CORRUPTED_GOTO(i == 1, error0);
991 if (xfs_alloc_compute_aligned(ltbno, ltlen,
992 args->alignment, args->minlen,
993 &ltbnoa, &ltlena))
994 break;
995 if ((error = xfs_alloc_decrement(bno_cur_lt, 0, &i)))
996 goto error0;
997 if (!i) {
998 xfs_btree_del_cursor(bno_cur_lt,
999 XFS_BTREE_NOERROR);
1000 bno_cur_lt = NULL;
1001 }
1002 }
1003 if (bno_cur_gt) {
1004 if ((error = xfs_alloc_get_rec(bno_cur_gt, &gtbno, &gtlen, &i)))
1005 goto error0;
1006 XFS_WANT_CORRUPTED_GOTO(i == 1, error0);
1007 if (xfs_alloc_compute_aligned(gtbno, gtlen,
1008 args->alignment, args->minlen,
1009 &gtbnoa, &gtlena))
1010 break;
1011 if ((error = xfs_alloc_increment(bno_cur_gt, 0, &i)))
1012 goto error0;
1013 if (!i) {
1014 xfs_btree_del_cursor(bno_cur_gt,
1015 XFS_BTREE_NOERROR);
1016 bno_cur_gt = NULL;
1017 }
1018 }
1019 } while (bno_cur_lt || bno_cur_gt);
1020 /*
1021 * Got both cursors still active, need to find better entry.
1022 */
1023 if (bno_cur_lt && bno_cur_gt) {
1024 /*
1025 * Left side is long enough, look for a right side entry.
1026 */
1027 if (ltlena >= args->minlen) {
1028 /*
1029 * Fix up the length.
1030 */
1031 args->len = XFS_EXTLEN_MIN(ltlena, args->maxlen);
1032 xfs_alloc_fix_len(args);
1033 rlen = args->len;
1034 ltdiff = xfs_alloc_compute_diff(args->agbno, rlen,
1035 args->alignment, ltbno, ltlen, &ltnew);
1036 /*
1037 * Not perfect.
1038 */
1039 if (ltdiff) {
1040 /*
1041 * Look until we find a better one, run out of
1042 * space, or run off the end.
1043 */
1044 while (bno_cur_lt && bno_cur_gt) {
1045 if ((error = xfs_alloc_get_rec(
1046 bno_cur_gt, &gtbno,
1047 &gtlen, &i)))
1048 goto error0;
1049 XFS_WANT_CORRUPTED_GOTO(i == 1, error0);
1050 xfs_alloc_compute_aligned(gtbno, gtlen,
1051 args->alignment, args->minlen,
1052 &gtbnoa, &gtlena);
1053 /*
1054 * The left one is clearly better.
1055 */
1056 if (gtbnoa >= args->agbno + ltdiff) {
1057 xfs_btree_del_cursor(
1058 bno_cur_gt,
1059 XFS_BTREE_NOERROR);
1060 bno_cur_gt = NULL;
1061 break;
1062 }
1063 /*
1064 * If we reach a big enough entry,
1065 * compare the two and pick the best.
1066 */
1067 if (gtlena >= args->minlen) {
1068 args->len =
1069 XFS_EXTLEN_MIN(gtlena,
1070 args->maxlen);
1071 xfs_alloc_fix_len(args);
1072 rlen = args->len;
1073 gtdiff = xfs_alloc_compute_diff(
1074 args->agbno, rlen,
1075 args->alignment,
1076 gtbno, gtlen, &gtnew);
1077 /*
1078 * Right side is better.
1079 */
1080 if (gtdiff < ltdiff) {
1081 xfs_btree_del_cursor(
1082 bno_cur_lt,
1083 XFS_BTREE_NOERROR);
1084 bno_cur_lt = NULL;
1085 }
1086 /*
1087 * Left side is better.
1088 */
1089 else {
1090 xfs_btree_del_cursor(
1091 bno_cur_gt,
1092 XFS_BTREE_NOERROR);
1093 bno_cur_gt = NULL;
1094 }
1095 break;
1096 }
1097 /*
1098 * Fell off the right end.
1099 */
1100 if ((error = xfs_alloc_increment(
1101 bno_cur_gt, 0, &i)))
1102 goto error0;
1103 if (!i) {
1104 xfs_btree_del_cursor(
1105 bno_cur_gt,
1106 XFS_BTREE_NOERROR);
1107 bno_cur_gt = NULL;
1108 break;
1109 }
1110 }
1111 }
1112 /*
1113 * The left side is perfect, trash the right side.
1114 */
1115 else {
1116 xfs_btree_del_cursor(bno_cur_gt,
1117 XFS_BTREE_NOERROR);
1118 bno_cur_gt = NULL;
1119 }
1120 }
1121 /*
1122 * It's the right side that was found first, look left.
1123 */
1124 else {
1125 /*
1126 * Fix up the length.
1127 */
1128 args->len = XFS_EXTLEN_MIN(gtlena, args->maxlen);
1129 xfs_alloc_fix_len(args);
1130 rlen = args->len;
1131 gtdiff = xfs_alloc_compute_diff(args->agbno, rlen,
1132 args->alignment, gtbno, gtlen, &gtnew);
1133 /*
1134 * Right side entry isn't perfect.
1135 */
1136 if (gtdiff) {
1137 /*
1138 * Look until we find a better one, run out of
1139 * space, or run off the end.
1140 */
1141 while (bno_cur_lt && bno_cur_gt) {
1142 if ((error = xfs_alloc_get_rec(
1143 bno_cur_lt, &ltbno,
1144 &ltlen, &i)))
1145 goto error0;
1146 XFS_WANT_CORRUPTED_GOTO(i == 1, error0);
1147 xfs_alloc_compute_aligned(ltbno, ltlen,
1148 args->alignment, args->minlen,
1149 &ltbnoa, &ltlena);
1150 /*
1151 * The right one is clearly better.
1152 */
1153 if (ltbnoa <= args->agbno - gtdiff) {
1154 xfs_btree_del_cursor(
1155 bno_cur_lt,
1156 XFS_BTREE_NOERROR);
1157 bno_cur_lt = NULL;
1158 break;
1159 }
1160 /*
1161 * If we reach a big enough entry,
1162 * compare the two and pick the best.
1163 */
1164 if (ltlena >= args->minlen) {
1165 args->len = XFS_EXTLEN_MIN(
1166 ltlena, args->maxlen);
1167 xfs_alloc_fix_len(args);
1168 rlen = args->len;
1169 ltdiff = xfs_alloc_compute_diff(
1170 args->agbno, rlen,
1171 args->alignment,
1172 ltbno, ltlen, &ltnew);
1173 /*
1174 * Left side is better.
1175 */
1176 if (ltdiff < gtdiff) {
1177 xfs_btree_del_cursor(
1178 bno_cur_gt,
1179 XFS_BTREE_NOERROR);
1180 bno_cur_gt = NULL;
1181 }
1182 /*
1183 * Right side is better.
1184 */
1185 else {
1186 xfs_btree_del_cursor(
1187 bno_cur_lt,
1188 XFS_BTREE_NOERROR);
1189 bno_cur_lt = NULL;
1190 }
1191 break;
1192 }
1193 /*
1194 * Fell off the left end.
1195 */
1196 if ((error = xfs_alloc_decrement(
1197 bno_cur_lt, 0, &i)))
1198 goto error0;
1199 if (!i) {
1200 xfs_btree_del_cursor(bno_cur_lt,
1201 XFS_BTREE_NOERROR);
1202 bno_cur_lt = NULL;
1203 break;
1204 }
1205 }
1206 }
1207 /*
1208 * The right side is perfect, trash the left side.
1209 */
1210 else {
1211 xfs_btree_del_cursor(bno_cur_lt,
1212 XFS_BTREE_NOERROR);
1213 bno_cur_lt = NULL;
1214 }
1215 }
1216 }
1217 /*
1218 * If we couldn't get anything, give up.
1219 */
1220 if (bno_cur_lt == NULL && bno_cur_gt == NULL) {
1221 TRACE_ALLOC("neither", args);
1222 args->agbno = NULLAGBLOCK;
1223 return 0;
1224 }
1225 /*
1226 * At this point we have selected a freespace entry, either to the
1227 * left or to the right. If it's on the right, copy all the
1228 * useful variables to the "left" set so we only have one
1229 * copy of this code.
1230 */
1231 if (bno_cur_gt) {
1232 bno_cur_lt = bno_cur_gt;
1233 bno_cur_gt = NULL;
1234 ltbno = gtbno;
1235 ltbnoa = gtbnoa;
1236 ltlen = gtlen;
1237 ltlena = gtlena;
1238 j = 1;
1239 } else
1240 j = 0;
1241 /*
1242 * Fix up the length and compute the useful address.
1243 */
1244 ltend = ltbno + ltlen;
1245 args->len = XFS_EXTLEN_MIN(ltlena, args->maxlen);
1246 xfs_alloc_fix_len(args);
1247 if (!xfs_alloc_fix_minleft(args)) {
1248 TRACE_ALLOC("nominleft", args);
1249 xfs_btree_del_cursor(bno_cur_lt, XFS_BTREE_NOERROR);
1250 xfs_btree_del_cursor(cnt_cur, XFS_BTREE_NOERROR);
1251 return 0;
1252 }
1253 rlen = args->len;
1254 (void)xfs_alloc_compute_diff(args->agbno, rlen, args->alignment, ltbno,
1255 ltlen, &ltnew);
1256 ASSERT(ltnew >= ltbno);
1257 ASSERT(ltnew + rlen <= ltend);
1258 ASSERT(ltnew + rlen <= INT_GET(XFS_BUF_TO_AGF(args->agbp)->agf_length,
1259 ARCH_CONVERT));
1260 args->agbno = ltnew;
1261 if ((error = xfs_alloc_fixup_trees(cnt_cur, bno_cur_lt, ltbno, ltlen,
1262 ltnew, rlen, XFSA_FIXUP_BNO_OK)))
1263 goto error0;
1264 TRACE_ALLOC(j ? "gt" : "lt", args);
1265 xfs_btree_del_cursor(cnt_cur, XFS_BTREE_NOERROR);
1266 xfs_btree_del_cursor(bno_cur_lt, XFS_BTREE_NOERROR);
1267 return 0;
1268
1269 error0:
1270 TRACE_ALLOC("error", args);
1271 if (cnt_cur != NULL)
1272 xfs_btree_del_cursor(cnt_cur, XFS_BTREE_ERROR);
1273 if (bno_cur_lt != NULL)
1274 xfs_btree_del_cursor(bno_cur_lt, XFS_BTREE_ERROR);
1275 if (bno_cur_gt != NULL)
1276 xfs_btree_del_cursor(bno_cur_gt, XFS_BTREE_ERROR);
1277 return error;
1278 }
1279
1280 /*
1281 * Allocate a variable extent anywhere in the allocation group agno.
1282 * Extent's length (returned in len) will be between minlen and maxlen,
1283 * and of the form k * prod + mod unless there's nothing that large.
1284 * Return the starting a.g. block, or NULLAGBLOCK if we can't do it.
1285 */
1286 STATIC int /* error */
1287 xfs_alloc_ag_vextent_size(
1288 xfs_alloc_arg_t *args) /* allocation argument structure */
1289 {
1290 xfs_btree_cur_t *bno_cur; /* cursor for bno btree */
1291 xfs_btree_cur_t *cnt_cur; /* cursor for cnt btree */
1292 int error; /* error result */
1293 xfs_agblock_t fbno; /* start of found freespace */
1294 xfs_extlen_t flen; /* length of found freespace */
1295 #ifdef XFS_ALLOC_TRACE
1296 static char fname[] = "xfs_alloc_ag_vextent_size";
1297 #endif
1298 int i; /* temp status variable */
1299 xfs_agblock_t rbno; /* returned block number */
1300 xfs_extlen_t rlen; /* length of returned extent */
1301
1302 /*
1303 * Allocate and initialize a cursor for the by-size btree.
1304 */
1305 cnt_cur = xfs_btree_init_cursor(args->mp, args->tp, args->agbp,
1306 args->agno, XFS_BTNUM_CNT, NULL, 0);
1307 bno_cur = NULL;
1308 /*
1309 * Look for an entry >= maxlen+alignment-1 blocks.
1310 */
1311 if ((error = xfs_alloc_lookup_ge(cnt_cur, 0,
1312 args->maxlen + args->alignment - 1, &i)))
1313 goto error0;
1314 /*
1315 * If none, then pick up the last entry in the tree unless the
1316 * tree is empty.
1317 */
1318 if (!i) {
1319 if ((error = xfs_alloc_ag_vextent_small(args, cnt_cur, &fbno,
1320 &flen, &i)))
1321 goto error0;
1322 if (i == 0 || flen == 0) {
1323 xfs_btree_del_cursor(cnt_cur, XFS_BTREE_NOERROR);
1324 TRACE_ALLOC("noentry", args);
1325 return 0;
1326 }
1327 ASSERT(i == 1);
1328 }
1329 /*
1330 * There's a freespace as big as maxlen+alignment-1, get it.
1331 */
1332 else {
1333 if ((error = xfs_alloc_get_rec(cnt_cur, &fbno, &flen, &i)))
1334 goto error0;
1335 XFS_WANT_CORRUPTED_GOTO(i == 1, error0);
1336 }
1337 /*
1338 * In the first case above, we got the last entry in the
1339 * by-size btree. Now we check to see if the space hits maxlen
1340 * once aligned; if not, we search left for something better.
1341 * This can't happen in the second case above.
1342 */
1343 xfs_alloc_compute_aligned(fbno, flen, args->alignment, args->minlen,
1344 &rbno, &rlen);
1345 rlen = XFS_EXTLEN_MIN(args->maxlen, rlen);
1346 XFS_WANT_CORRUPTED_GOTO(rlen == 0 ||
1347 (rlen <= flen && rbno + rlen <= fbno + flen), error0);
1348 if (rlen < args->maxlen) {
1349 xfs_agblock_t bestfbno;
1350 xfs_extlen_t bestflen;
1351 xfs_agblock_t bestrbno;
1352 xfs_extlen_t bestrlen;
1353
1354 bestrlen = rlen;
1355 bestrbno = rbno;
1356 bestflen = flen;
1357 bestfbno = fbno;
1358 for (;;) {
1359 if ((error = xfs_alloc_decrement(cnt_cur, 0, &i)))
1360 goto error0;
1361 if (i == 0)
1362 break;
1363 if ((error = xfs_alloc_get_rec(cnt_cur, &fbno, &flen,
1364 &i)))
1365 goto error0;
1366 XFS_WANT_CORRUPTED_GOTO(i == 1, error0);
1367 if (flen < bestrlen)
1368 break;
1369 xfs_alloc_compute_aligned(fbno, flen, args->alignment,
1370 args->minlen, &rbno, &rlen);
1371 rlen = XFS_EXTLEN_MIN(args->maxlen, rlen);
1372 XFS_WANT_CORRUPTED_GOTO(rlen == 0 ||
1373 (rlen <= flen && rbno + rlen <= fbno + flen),
1374 error0);
1375 if (rlen > bestrlen) {
1376 bestrlen = rlen;
1377 bestrbno = rbno;
1378 bestflen = flen;
1379 bestfbno = fbno;
1380 if (rlen == args->maxlen)
1381 break;
1382 }
1383 }
1384 if ((error = xfs_alloc_lookup_eq(cnt_cur, bestfbno, bestflen,
1385 &i)))
1386 goto error0;
1387 XFS_WANT_CORRUPTED_GOTO(i == 1, error0);
1388 rlen = bestrlen;
1389 rbno = bestrbno;
1390 flen = bestflen;
1391 fbno = bestfbno;
1392 }
1393 args->wasfromfl = 0;
1394 /*
1395 * Fix up the length.
1396 */
1397 args->len = rlen;
1398 xfs_alloc_fix_len(args);
1399 if (rlen < args->minlen || !xfs_alloc_fix_minleft(args)) {
1400 xfs_btree_del_cursor(cnt_cur, XFS_BTREE_NOERROR);
1401 TRACE_ALLOC("nominleft", args);
1402 args->agbno = NULLAGBLOCK;
1403 return 0;
1404 }
1405 rlen = args->len;
1406 XFS_WANT_CORRUPTED_GOTO(rlen <= flen, error0);
1407 /*
1408 * Allocate and initialize a cursor for the by-block tree.
1409 */
1410 bno_cur = xfs_btree_init_cursor(args->mp, args->tp, args->agbp,
1411 args->agno, XFS_BTNUM_BNO, NULL, 0);
1412 if ((error = xfs_alloc_fixup_trees(cnt_cur, bno_cur, fbno, flen,
1413 rbno, rlen, XFSA_FIXUP_CNT_OK)))
1414 goto error0;
1415 xfs_btree_del_cursor(cnt_cur, XFS_BTREE_NOERROR);
1416 xfs_btree_del_cursor(bno_cur, XFS_BTREE_NOERROR);
1417 cnt_cur = bno_cur = NULL;
1418 args->len = rlen;
1419 args->agbno = rbno;
1420 XFS_WANT_CORRUPTED_GOTO(
1421 args->agbno + args->len <=
1422 INT_GET(XFS_BUF_TO_AGF(args->agbp)->agf_length,
1423 ARCH_CONVERT),
1424 error0);
1425 TRACE_ALLOC("normal", args);
1426 return 0;
1427
1428 error0:
1429 TRACE_ALLOC("error", args);
1430 if (cnt_cur)
1431 xfs_btree_del_cursor(cnt_cur, XFS_BTREE_ERROR);
1432 if (bno_cur)
1433 xfs_btree_del_cursor(bno_cur, XFS_BTREE_ERROR);
1434 return error;
1435 }
1436
1437 /*
1438 * Deal with the case where only small freespaces remain.
1439 * Either return the contents of the last freespace record,
1440 * or allocate space from the freelist if there is nothing in the tree.
1441 */
1442 STATIC int /* error */
1443 xfs_alloc_ag_vextent_small(
1444 xfs_alloc_arg_t *args, /* allocation argument structure */
1445 xfs_btree_cur_t *ccur, /* by-size cursor */
1446 xfs_agblock_t *fbnop, /* result block number */
1447 xfs_extlen_t *flenp, /* result length */
1448 int *stat) /* status: 0-freelist, 1-normal/none */
1449 {
1450 int error;
1451 xfs_agblock_t fbno;
1452 xfs_extlen_t flen;
1453 #ifdef XFS_ALLOC_TRACE
1454 static char fname[] = "xfs_alloc_ag_vextent_small";
1455 #endif
1456 int i;
1457
1458 if ((error = xfs_alloc_decrement(ccur, 0, &i)))
1459 goto error0;
1460 if (i) {
1461 if ((error = xfs_alloc_get_rec(ccur, &fbno, &flen, &i)))
1462 goto error0;
1463 XFS_WANT_CORRUPTED_GOTO(i == 1, error0);
1464 }
1465 /*
1466 * Nothing in the btree, try the freelist. Make sure
1467 * to respect minleft even when pulling from the
1468 * freelist.
1469 */
1470 else if (args->minlen == 1 && args->alignment == 1 && !args->isfl &&
1471 (INT_GET(XFS_BUF_TO_AGF(args->agbp)->agf_flcount,
1472 ARCH_CONVERT) > args->minleft)) {
1473 if ((error = xfs_alloc_get_freelist(args->tp, args->agbp, &fbno)))
1474 goto error0;
1475 if (fbno != NULLAGBLOCK) {
1476 if (args->userdata) {
1477 xfs_buf_t *bp;
1478
1479 bp = xfs_btree_get_bufs(args->mp, args->tp,
1480 args->agno, fbno, 0);
1481 xfs_trans_binval(args->tp, bp);
1482 }
1483 args->len = 1;
1484 args->agbno = fbno;
1485 XFS_WANT_CORRUPTED_GOTO(
1486 args->agbno + args->len <=
1487 INT_GET(XFS_BUF_TO_AGF(args->agbp)->agf_length,
1488 ARCH_CONVERT),
1489 error0);
1490 args->wasfromfl = 1;
1491 TRACE_ALLOC("freelist", args);
1492 *stat = 0;
1493 return 0;
1494 }
1495 /*
1496 * Nothing in the freelist.
1497 */
1498 else
1499 flen = 0;
1500 }
1501 /*
1502 * Can't allocate from the freelist for some reason.
1503 */
1504 else
1505 flen = 0;
1506 /*
1507 * Can't do the allocation, give up.
1508 */
1509 if (flen < args->minlen) {
1510 args->agbno = NULLAGBLOCK;
1511 TRACE_ALLOC("notenough", args);
1512 flen = 0;
1513 }
1514 *fbnop = fbno;
1515 *flenp = flen;
1516 *stat = 1;
1517 TRACE_ALLOC("normal", args);
1518 return 0;
1519
1520 error0:
1521 TRACE_ALLOC("error", args);
1522 return error;
1523 }
1524
1525 /*
1526 * Free the extent starting at agno/bno for length.
1527 */
1528 STATIC int /* error */
1529 xfs_free_ag_extent(
1530 xfs_trans_t *tp, /* transaction pointer */
1531 xfs_buf_t *agbp, /* buffer for a.g. freelist header */
1532 xfs_agnumber_t agno, /* allocation group number */
1533 xfs_agblock_t bno, /* starting block number */
1534 xfs_extlen_t len, /* length of extent */
1535 int isfl) /* set if is freelist blocks - no sb acctg */
1536 {
1537 xfs_btree_cur_t *bno_cur; /* cursor for by-block btree */
1538 xfs_btree_cur_t *cnt_cur; /* cursor for by-size btree */
1539 int error; /* error return value */
1540 #ifdef XFS_ALLOC_TRACE
1541 static char fname[] = "xfs_free_ag_extent";
1542 #endif
1543 xfs_agblock_t gtbno; /* start of right neighbor block */
1544 xfs_extlen_t gtlen; /* length of right neighbor block */
1545 int haveleft; /* have a left neighbor block */
1546 int haveright; /* have a right neighbor block */
1547 int i; /* temp, result code */
1548 xfs_agblock_t ltbno; /* start of left neighbor block */
1549 xfs_extlen_t ltlen; /* length of left neighbor block */
1550 xfs_mount_t *mp; /* mount point struct for filesystem */
1551 xfs_agblock_t nbno; /* new starting block of freespace */
1552 xfs_extlen_t nlen; /* new length of freespace */
1553
1554 mp = tp->t_mountp;
1555 /*
1556 * Allocate and initialize a cursor for the by-block btree.
1557 */
1558 bno_cur = xfs_btree_init_cursor(mp, tp, agbp, agno, XFS_BTNUM_BNO, NULL,
1559 0);
1560 cnt_cur = NULL;
1561 /*
1562 * Look for a neighboring block on the left (lower block numbers)
1563 * that is contiguous with this space.
1564 */
1565 if ((error = xfs_alloc_lookup_le(bno_cur, bno, len, &haveleft)))
1566 goto error0;
1567 if (haveleft) {
1568 /*
1569 * There is a block to our left.
1570 */
1571 if ((error = xfs_alloc_get_rec(bno_cur, &ltbno, &ltlen, &i)))
1572 goto error0;
1573 XFS_WANT_CORRUPTED_GOTO(i == 1, error0);
1574 /*
1575 * It's not contiguous, though.
1576 */
1577 if (ltbno + ltlen < bno)
1578 haveleft = 0;
1579 else {
1580 /*
1581 * If this failure happens the request to free this
1582 * space was invalid, it's (partly) already free.
1583 * Very bad.
1584 */
1585 XFS_WANT_CORRUPTED_GOTO(ltbno + ltlen <= bno, error0);
1586 }
1587 }
1588 /*
1589 * Look for a neighboring block on the right (higher block numbers)
1590 * that is contiguous with this space.
1591 */
1592 if ((error = xfs_alloc_increment(bno_cur, 0, &haveright)))
1593 goto error0;
1594 if (haveright) {
1595 /*
1596 * There is a block to our right.
1597 */
1598 if ((error = xfs_alloc_get_rec(bno_cur, &gtbno, &gtlen, &i)))
1599 goto error0;
1600 XFS_WANT_CORRUPTED_GOTO(i == 1, error0);
1601 /*
1602 * It's not contiguous, though.
1603 */
1604 if (bno + len < gtbno)
1605 haveright = 0;
1606 else {
1607 /*
1608 * If this failure happens the request to free this
1609 * space was invalid, it's (partly) already free.
1610 * Very bad.
1611 */
1612 XFS_WANT_CORRUPTED_GOTO(gtbno >= bno + len, error0);
1613 }
1614 }
1615 /*
1616 * Now allocate and initialize a cursor for the by-size tree.
1617 */
1618 cnt_cur = xfs_btree_init_cursor(mp, tp, agbp, agno, XFS_BTNUM_CNT, NULL,
1619 0);
1620 /*
1621 * Have both left and right contiguous neighbors.
1622 * Merge all three into a single free block.
1623 */
1624 if (haveleft && haveright) {
1625 /*
1626 * Delete the old by-size entry on the left.
1627 */
1628 if ((error = xfs_alloc_lookup_eq(cnt_cur, ltbno, ltlen, &i)))
1629 goto error0;
1630 XFS_WANT_CORRUPTED_GOTO(i == 1, error0);
1631 if ((error = xfs_alloc_delete(cnt_cur, &i)))
1632 goto error0;
1633 XFS_WANT_CORRUPTED_GOTO(i == 1, error0);
1634 /*
1635 * Delete the old by-size entry on the right.
1636 */
1637 if ((error = xfs_alloc_lookup_eq(cnt_cur, gtbno, gtlen, &i)))
1638 goto error0;
1639 XFS_WANT_CORRUPTED_GOTO(i == 1, error0);
1640 if ((error = xfs_alloc_delete(cnt_cur, &i)))
1641 goto error0;
1642 XFS_WANT_CORRUPTED_GOTO(i == 1, error0);
1643 /*
1644 * Delete the old by-block entry for the right block.
1645 */
1646 if ((error = xfs_alloc_delete(bno_cur, &i)))
1647 goto error0;
1648 XFS_WANT_CORRUPTED_GOTO(i == 1, error0);
1649 /*
1650 * Move the by-block cursor back to the left neighbor.
1651 */
1652 if ((error = xfs_alloc_decrement(bno_cur, 0, &i)))
1653 goto error0;
1654 XFS_WANT_CORRUPTED_GOTO(i == 1, error0);
1655 #ifdef DEBUG
1656 /*
1657 * Check that this is the right record: delete didn't
1658 * mangle the cursor.
1659 */
1660 {
1661 xfs_agblock_t xxbno;
1662 xfs_extlen_t xxlen;
1663
1664 if ((error = xfs_alloc_get_rec(bno_cur, &xxbno, &xxlen,
1665 &i)))
1666 goto error0;
1667 XFS_WANT_CORRUPTED_GOTO(
1668 i == 1 && xxbno == ltbno && xxlen == ltlen,
1669 error0);
1670 }
1671 #endif
1672 /*
1673 * Update remaining by-block entry to the new, joined block.
1674 */
1675 nbno = ltbno;
1676 nlen = len + ltlen + gtlen;
1677 if ((error = xfs_alloc_update(bno_cur, nbno, nlen)))
1678 goto error0;
1679 }
1680 /*
1681 * Have only a left contiguous neighbor.
1682 * Merge it together with the new freespace.
1683 */
1684 else if (haveleft) {
1685 /*
1686 * Delete the old by-size entry on the left.
1687 */
1688 if ((error = xfs_alloc_lookup_eq(cnt_cur, ltbno, ltlen, &i)))
1689 goto error0;
1690 XFS_WANT_CORRUPTED_GOTO(i == 1, error0);
1691 if ((error = xfs_alloc_delete(cnt_cur, &i)))
1692 goto error0;
1693 XFS_WANT_CORRUPTED_GOTO(i == 1, error0);
1694 /*
1695 * Back up the by-block cursor to the left neighbor, and
1696 * update its length.
1697 */
1698 if ((error = xfs_alloc_decrement(bno_cur, 0, &i)))
1699 goto error0;
1700 XFS_WANT_CORRUPTED_GOTO(i == 1, error0);
1701 nbno = ltbno;
1702 nlen = len + ltlen;
1703 if ((error = xfs_alloc_update(bno_cur, nbno, nlen)))
1704 goto error0;
1705 }
1706 /*
1707 * Have only a right contiguous neighbor.
1708 * Merge it together with the new freespace.
1709 */
1710 else if (haveright) {
1711 /*
1712 * Delete the old by-size entry on the right.
1713 */
1714 if ((error = xfs_alloc_lookup_eq(cnt_cur, gtbno, gtlen, &i)))
1715 goto error0;
1716 XFS_WANT_CORRUPTED_GOTO(i == 1, error0);
1717 if ((error = xfs_alloc_delete(cnt_cur, &i)))
1718 goto error0;
1719 XFS_WANT_CORRUPTED_GOTO(i == 1, error0);
1720 /*
1721 * Update the starting block and length of the right
1722 * neighbor in the by-block tree.
1723 */
1724 nbno = bno;
1725 nlen = len + gtlen;
1726 if ((error = xfs_alloc_update(bno_cur, nbno, nlen)))
1727 goto error0;
1728 }
1729 /*
1730 * No contiguous neighbors.
1731 * Insert the new freespace into the by-block tree.
1732 */
1733 else {
1734 nbno = bno;
1735 nlen = len;
1736 if ((error = xfs_alloc_insert(bno_cur, &i)))
1737 goto error0;
1738 XFS_WANT_CORRUPTED_GOTO(i == 1, error0);
1739 }
1740 xfs_btree_del_cursor(bno_cur, XFS_BTREE_NOERROR);
1741 bno_cur = NULL;
1742 /*
1743 * In all cases we need to insert the new freespace in the by-size tree.
1744 */
1745 if ((error = xfs_alloc_lookup_eq(cnt_cur, nbno, nlen, &i)))
1746 goto error0;
1747 XFS_WANT_CORRUPTED_GOTO(i == 0, error0);
1748 if ((error = xfs_alloc_insert(cnt_cur, &i)))
1749 goto error0;
1750 XFS_WANT_CORRUPTED_GOTO(i == 1, error0);
1751 xfs_btree_del_cursor(cnt_cur, XFS_BTREE_NOERROR);
1752 cnt_cur = NULL;
1753 /*
1754 * Update the freespace totals in the ag and superblock.
1755 */
1756 {
1757 xfs_agf_t *agf;
1758 xfs_perag_t *pag; /* per allocation group data */
1759
1760 agf = XFS_BUF_TO_AGF(agbp);
1761 pag = &mp->m_perag[agno];
1762 INT_MOD(agf->agf_freeblks, ARCH_CONVERT, len);
1763 xfs_trans_agblocks_delta(tp, len);
1764 pag->pagf_freeblks += len;
1765 XFS_WANT_CORRUPTED_GOTO(
1766 INT_GET(agf->agf_freeblks, ARCH_CONVERT)
1767 <= INT_GET(agf->agf_length, ARCH_CONVERT),
1768 error0);
1769 TRACE_MODAGF(NULL, agf, XFS_AGF_FREEBLKS);
1770 xfs_alloc_log_agf(tp, agbp, XFS_AGF_FREEBLKS);
1771 if (!isfl)
1772 xfs_trans_mod_sb(tp, XFS_TRANS_SB_FDBLOCKS, (long)len);
1773 XFS_STATS_INC(xs_freex);
1774 XFS_STATS_ADD(xs_freeb, len);
1775 }
1776 TRACE_FREE(haveleft ?
1777 (haveright ? "both" : "left") :
1778 (haveright ? "right" : "none"),
1779 agno, bno, len, isfl);
1780
1781 /*
1782 * Since blocks move to the free list without the coordination
1783 * used in xfs_bmap_finish, we can't allow block to be available
1784 * for reallocation and non-transaction writing (user data)
1785 * until we know that the transaction that moved it to the free
1786 * list is permanently on disk. We track the blocks by declaring
1787 * these blocks as "busy"; the busy list is maintained on a per-ag
1788 * basis and each transaction records which entries should be removed
1789 * when the iclog commits to disk. If a busy block is allocated,
1790 * the iclog is pushed up to the LSN that freed the block.
1791 */
1792 xfs_alloc_mark_busy(tp, agno, bno, len);
1793 return 0;
1794
1795 error0:
1796 TRACE_FREE("error", agno, bno, len, isfl);
1797 if (bno_cur)
1798 xfs_btree_del_cursor(bno_cur, XFS_BTREE_ERROR);
1799 if (cnt_cur)
1800 xfs_btree_del_cursor(cnt_cur, XFS_BTREE_ERROR);
1801 return error;
1802 }
1803
1804 /*
1805 * Visible (exported) allocation/free functions.
1806 * Some of these are used just by xfs_alloc_btree.c and this file.
1807 */
1808
1809 /*
1810 * Compute and fill in value of m_ag_maxlevels.
1811 */
1812 void
1813 xfs_alloc_compute_maxlevels(
1814 xfs_mount_t *mp) /* file system mount structure */
1815 {
1816 int level;
1817 uint maxblocks;
1818 uint maxleafents;
1819 int minleafrecs;
1820 int minnoderecs;
1821
1822 maxleafents = (mp->m_sb.sb_agblocks + 1) / 2;
1823 minleafrecs = mp->m_alloc_mnr[0];
1824 minnoderecs = mp->m_alloc_mnr[1];
1825 maxblocks = (maxleafents + minleafrecs - 1) / minleafrecs;
1826 for (level = 1; maxblocks > 1; level++)
1827 maxblocks = (maxblocks + minnoderecs - 1) / minnoderecs;
1828 mp->m_ag_maxlevels = level;
1829 }
1830
1831 /*
1832 * Decide whether to use this allocation group for this allocation.
1833 * If so, fix up the btree freelist's size.
1834 */
1835 STATIC int /* error */
1836 xfs_alloc_fix_freelist(
1837 xfs_alloc_arg_t *args, /* allocation argument structure */
1838 int flags) /* XFS_ALLOC_FLAG_... */
1839 {
1840 xfs_buf_t *agbp; /* agf buffer pointer */
1841 xfs_agf_t *agf; /* a.g. freespace structure pointer */
1842 xfs_buf_t *agflbp;/* agfl buffer pointer */
1843 xfs_agblock_t bno; /* freelist block */
1844 xfs_extlen_t delta; /* new blocks needed in freelist */
1845 int error; /* error result code */
1846 xfs_extlen_t longest;/* longest extent in allocation group */
1847 xfs_mount_t *mp; /* file system mount point structure */
1848 xfs_extlen_t need; /* total blocks needed in freelist */
1849 xfs_perag_t *pag; /* per-ag information structure */
1850 xfs_alloc_arg_t targs; /* local allocation arguments */
1851 xfs_trans_t *tp; /* transaction pointer */
1852
1853 mp = args->mp;
1854
1855 pag = args->pag;
1856 tp = args->tp;
1857 if (!pag->pagf_init) {
1858 if ((error = xfs_alloc_read_agf(mp, tp, args->agno, flags,
1859 &agbp)))
1860 return error;
1861 if (!pag->pagf_init) {
1862 args->agbp = NULL;
1863 return 0;
1864 }
1865 } else
1866 agbp = NULL;
1867
1868 /* If this is a metadata prefered pag and we are user data
1869 * then try somewhere else if we are not being asked to
1870 * try harder at this point
1871 */
1872 if (pag->pagf_metadata && args->userdata && flags) {
1873 args->agbp = NULL;
1874 return 0;
1875 }
1876
1877 need = XFS_MIN_FREELIST_PAG(pag, mp);
1878 delta = need > pag->pagf_flcount ? need - pag->pagf_flcount : 0;
1879 /*
1880 * If it looks like there isn't a long enough extent, or enough
1881 * total blocks, reject it.
1882 */
1883 longest = (pag->pagf_longest > delta) ?
1884 (pag->pagf_longest - delta) :
1885 (pag->pagf_flcount > 0 || pag->pagf_longest > 0);
1886 if (args->minlen + args->alignment + args->minalignslop - 1 > longest ||
1887 (args->minleft &&
1888 (int)(pag->pagf_freeblks + pag->pagf_flcount -
1889 need - args->total) <
1890 (int)args->minleft)) {
1891 if (agbp)
1892 xfs_trans_brelse(tp, agbp);
1893 args->agbp = NULL;
1894 return 0;
1895 }
1896 /*
1897 * Get the a.g. freespace buffer.
1898 * Can fail if we're not blocking on locks, and it's held.
1899 */
1900 if (agbp == NULL) {
1901 if ((error = xfs_alloc_read_agf(mp, tp, args->agno, flags,
1902 &agbp)))
1903 return error;
1904 if (agbp == NULL) {
1905 args->agbp = NULL;
1906 return 0;
1907 }
1908 }
1909 /*
1910 * Figure out how many blocks we should have in the freelist.
1911 */
1912 agf = XFS_BUF_TO_AGF(agbp);
1913 need = XFS_MIN_FREELIST(agf, mp);
1914 delta = need > INT_GET(agf->agf_flcount, ARCH_CONVERT) ?
1915 (need - INT_GET(agf->agf_flcount, ARCH_CONVERT)) : 0;
1916 /*
1917 * If there isn't enough total or single-extent, reject it.
1918 */
1919 longest = INT_GET(agf->agf_longest, ARCH_CONVERT);
1920 longest = (longest > delta) ? (longest - delta) :
1921 (INT_GET(agf->agf_flcount, ARCH_CONVERT) > 0 || longest > 0);
1922 if (args->minlen + args->alignment + args->minalignslop - 1 > longest ||
1923 (args->minleft &&
1924 (int)(INT_GET(agf->agf_freeblks, ARCH_CONVERT) +
1925 INT_GET(agf->agf_flcount, ARCH_CONVERT) - need - args->total) <
1926 (int)args->minleft)) {
1927 xfs_trans_brelse(tp, agbp);
1928 args->agbp = NULL;
1929 return 0;
1930 }
1931 /*
1932 * Make the freelist shorter if it's too long.
1933 */
1934 while (INT_GET(agf->agf_flcount, ARCH_CONVERT) > need) {
1935 xfs_buf_t *bp;
1936
1937 if ((error = xfs_alloc_get_freelist(tp, agbp, &bno)))
1938 return error;
1939 if ((error = xfs_free_ag_extent(tp, agbp, args->agno, bno, 1, 1)))
1940 return error;
1941 bp = xfs_btree_get_bufs(mp, tp, args->agno, bno, 0);
1942 xfs_trans_binval(tp, bp);
1943 }
1944 /*
1945 * Initialize the args structure.
1946 */
1947 targs.tp = tp;
1948 targs.mp = mp;
1949 targs.agbp = agbp;
1950 targs.agno = args->agno;
1951 targs.mod = targs.minleft = targs.wasdel = targs.userdata =
1952 targs.minalignslop = 0;
1953 targs.alignment = targs.minlen = targs.prod = targs.isfl = 1;
1954 targs.type = XFS_ALLOCTYPE_THIS_AG;
1955 targs.pag = pag;
1956 if ((error = xfs_alloc_read_agfl(mp, tp, targs.agno, &agflbp)))
1957 return error;
1958 /*
1959 * Make the freelist longer if it's too short.
1960 */
1961 while (INT_GET(agf->agf_flcount, ARCH_CONVERT) < need) {
1962 targs.agbno = 0;
1963 targs.maxlen = need - INT_GET(agf->agf_flcount, ARCH_CONVERT);
1964 /*
1965 * Allocate as many blocks as possible at once.
1966 */
1967 if ((error = xfs_alloc_ag_vextent(&targs)))
1968 return error;
1969 /*
1970 * Stop if we run out. Won't happen if callers are obeying
1971 * the restrictions correctly. Can happen for free calls
1972 * on a completely full ag.
1973 */
1974 if (targs.agbno == NULLAGBLOCK)
1975 break;
1976 /*
1977 * Put each allocated block on the list.
1978 */
1979 for (bno = targs.agbno; bno < targs.agbno + targs.len; bno++) {
1980 if ((error = xfs_alloc_put_freelist(tp, agbp, agflbp,
1981 bno)))
1982 return error;
1983 }
1984 }
1985 args->agbp = agbp;
1986 return 0;
1987 }
1988
1989 /*
1990 * Get a block from the freelist.
1991 * Returns with the buffer for the block gotten.
1992 */
1993 int /* error */
1994 xfs_alloc_get_freelist(
1995 xfs_trans_t *tp, /* transaction pointer */
1996 xfs_buf_t *agbp, /* buffer containing the agf structure */
1997 xfs_agblock_t *bnop) /* block address retrieved from freelist */
1998 {
1999 xfs_agf_t *agf; /* a.g. freespace structure */
2000 xfs_agfl_t *agfl; /* a.g. freelist structure */
2001 xfs_buf_t *agflbp;/* buffer for a.g. freelist structure */
2002 xfs_agblock_t bno; /* block number returned */
2003 int error;
2004 #ifdef XFS_ALLOC_TRACE
2005 static char fname[] = "xfs_alloc_get_freelist";
2006 #endif
2007 xfs_mount_t *mp; /* mount structure */
2008 xfs_perag_t *pag; /* per allocation group data */
2009
2010 agf = XFS_BUF_TO_AGF(agbp);
2011 /*
2012 * Freelist is empty, give up.
2013 */
2014 if (!agf->agf_flcount) {
2015 *bnop = NULLAGBLOCK;
2016 return 0;
2017 }
2018 /*
2019 * Read the array of free blocks.
2020 */
2021 mp = tp->t_mountp;
2022 if ((error = xfs_alloc_read_agfl(mp, tp,
2023 INT_GET(agf->agf_seqno, ARCH_CONVERT), &agflbp)))
2024 return error;
2025 agfl = XFS_BUF_TO_AGFL(agflbp);
2026 /*
2027 * Get the block number and update the data structures.
2028 */
2029 bno = INT_GET(agfl->agfl_bno[INT_GET(agf->agf_flfirst, ARCH_CONVERT)], ARCH_CONVERT);
2030 INT_MOD(agf->agf_flfirst, ARCH_CONVERT, 1);
2031 xfs_trans_brelse(tp, agflbp);
2032 if (INT_GET(agf->agf_flfirst, ARCH_CONVERT) == XFS_AGFL_SIZE(mp))
2033 agf->agf_flfirst = 0;
2034 pag = &mp->m_perag[INT_GET(agf->agf_seqno, ARCH_CONVERT)];
2035 INT_MOD(agf->agf_flcount, ARCH_CONVERT, -1);
2036 xfs_trans_agflist_delta(tp, -1);
2037 pag->pagf_flcount--;
2038 TRACE_MODAGF(NULL, agf, XFS_AGF_FLFIRST | XFS_AGF_FLCOUNT);
2039 xfs_alloc_log_agf(tp, agbp, XFS_AGF_FLFIRST | XFS_AGF_FLCOUNT);
2040 *bnop = bno;
2041
2042 /*
2043 * As blocks are freed, they are added to the per-ag busy list
2044 * and remain there until the freeing transaction is committed to
2045 * disk. Now that we have allocated blocks, this list must be
2046 * searched to see if a block is being reused. If one is, then
2047 * the freeing transaction must be pushed to disk NOW by forcing
2048 * to disk all iclogs up that transaction's LSN.
2049 */
2050 xfs_alloc_search_busy(tp, INT_GET(agf->agf_seqno, ARCH_CONVERT), bno, 1);
2051 return 0;
2052 }
2053
2054 /*
2055 * Log the given fields from the agf structure.
2056 */
2057 void
2058 xfs_alloc_log_agf(
2059 xfs_trans_t *tp, /* transaction pointer */
2060 xfs_buf_t *bp, /* buffer for a.g. freelist header */
2061 int fields) /* mask of fields to be logged (XFS_AGF_...) */
2062 {
2063 int first; /* first byte offset */
2064 int last; /* last byte offset */
2065 static const short offsets[] = {
2066 offsetof(xfs_agf_t, agf_magicnum),
2067 offsetof(xfs_agf_t, agf_versionnum),
2068 offsetof(xfs_agf_t, agf_seqno),
2069 offsetof(xfs_agf_t, agf_length),
2070 offsetof(xfs_agf_t, agf_roots[0]),
2071 offsetof(xfs_agf_t, agf_levels[0]),
2072 offsetof(xfs_agf_t, agf_flfirst),
2073 offsetof(xfs_agf_t, agf_fllast),
2074 offsetof(xfs_agf_t, agf_flcount),
2075 offsetof(xfs_agf_t, agf_freeblks),
2076 offsetof(xfs_agf_t, agf_longest),
2077 sizeof(xfs_agf_t)
2078 };
2079
2080 xfs_btree_offsets(fields, offsets, XFS_AGF_NUM_BITS, &first, &last);
2081 xfs_trans_log_buf(tp, bp, (uint)first, (uint)last);
2082 }
2083
2084 /*
2085 * Interface for inode allocation to force the pag data to be initialized.
2086 */
2087 int /* error */
2088 xfs_alloc_pagf_init(
2089 xfs_mount_t *mp, /* file system mount structure */
2090 xfs_trans_t *tp, /* transaction pointer */
2091 xfs_agnumber_t agno, /* allocation group number */
2092 int flags) /* XFS_ALLOC_FLAGS_... */
2093 {
2094 xfs_buf_t *bp;
2095 int error;
2096
2097 if ((error = xfs_alloc_read_agf(mp, tp, agno, flags, &bp)))
2098 return error;
2099 if (bp)
2100 xfs_trans_brelse(tp, bp);
2101 return 0;
2102 }
2103
2104 /*
2105 * Put the block on the freelist for the allocation group.
2106 */
2107 int /* error */
2108 xfs_alloc_put_freelist(
2109 xfs_trans_t *tp, /* transaction pointer */
2110 xfs_buf_t *agbp, /* buffer for a.g. freelist header */
2111 xfs_buf_t *agflbp,/* buffer for a.g. free block array */
2112 xfs_agblock_t bno) /* block being freed */
2113 {
2114 xfs_agf_t *agf; /* a.g. freespace structure */
2115 xfs_agfl_t *agfl; /* a.g. free block array */
2116 xfs_agblock_t *blockp;/* pointer to array entry */
2117 int error;
2118 #ifdef XFS_ALLOC_TRACE
2119 static char fname[] = "xfs_alloc_put_freelist";
2120 #endif
2121 xfs_mount_t *mp; /* mount structure */
2122 xfs_perag_t *pag; /* per allocation group data */
2123
2124 agf = XFS_BUF_TO_AGF(agbp);
2125 mp = tp->t_mountp;
2126
2127 if (!agflbp && (error = xfs_alloc_read_agfl(mp, tp,
2128 INT_GET(agf->agf_seqno, ARCH_CONVERT), &agflbp)))
2129 return error;
2130 agfl = XFS_BUF_TO_AGFL(agflbp);
2131 INT_MOD(agf->agf_fllast, ARCH_CONVERT, 1);
2132 if (INT_GET(agf->agf_fllast, ARCH_CONVERT) == XFS_AGFL_SIZE(mp))
2133 agf->agf_fllast = 0;
2134 pag = &mp->m_perag[INT_GET(agf->agf_seqno, ARCH_CONVERT)];
2135 INT_MOD(agf->agf_flcount, ARCH_CONVERT, 1);
2136 xfs_trans_agflist_delta(tp, 1);
2137 pag->pagf_flcount++;
2138 ASSERT(INT_GET(agf->agf_flcount, ARCH_CONVERT) <= XFS_AGFL_SIZE(mp));
2139 blockp = &agfl->agfl_bno[INT_GET(agf->agf_fllast, ARCH_CONVERT)];
2140 INT_SET(*blockp, ARCH_CONVERT, bno);
2141 TRACE_MODAGF(NULL, agf, XFS_AGF_FLLAST | XFS_AGF_FLCOUNT);
2142 xfs_alloc_log_agf(tp, agbp, XFS_AGF_FLLAST | XFS_AGF_FLCOUNT);
2143 xfs_trans_log_buf(tp, agflbp,
2144 (int)((xfs_caddr_t)blockp - (xfs_caddr_t)agfl),
2145 (int)((xfs_caddr_t)blockp - (xfs_caddr_t)agfl +
2146 sizeof(xfs_agblock_t) - 1));
2147 return 0;
2148 }
2149
2150 /*
2151 * Read in the allocation group header (free/alloc section).
2152 */
2153 int /* error */
2154 xfs_alloc_read_agf(
2155 xfs_mount_t *mp, /* mount point structure */
2156 xfs_trans_t *tp, /* transaction pointer */
2157 xfs_agnumber_t agno, /* allocation group number */
2158 int flags, /* XFS_ALLOC_FLAG_... */
2159 xfs_buf_t **bpp) /* buffer for the ag freelist header */
2160 {
2161 xfs_agf_t *agf; /* ag freelist header */
2162 int agf_ok; /* set if agf is consistent */
2163 xfs_buf_t *bp; /* return value */
2164 xfs_perag_t *pag; /* per allocation group data */
2165 int error;
2166
2167 ASSERT(agno != NULLAGNUMBER);
2168 error = xfs_trans_read_buf(
2169 mp, tp, mp->m_ddev_targp,
2170 XFS_AG_DADDR(mp, agno, XFS_AGF_DADDR(mp)),
2171 XFS_FSS_TO_BB(mp, 1),
2172 (flags & XFS_ALLOC_FLAG_TRYLOCK) ? XFS_BUF_TRYLOCK : 0U,
2173 &bp);
2174 if (error)
2175 return error;
2176 ASSERT(!bp || !XFS_BUF_GETERROR(bp));
2177 if (!bp) {
2178 *bpp = NULL;
2179 return 0;
2180 }
2181 /*
2182 * Validate the magic number of the agf block.
2183 */
2184 agf = XFS_BUF_TO_AGF(bp);
2185 agf_ok =
2186 INT_GET(agf->agf_magicnum, ARCH_CONVERT) == XFS_AGF_MAGIC &&
2187 XFS_AGF_GOOD_VERSION(
2188 INT_GET(agf->agf_versionnum, ARCH_CONVERT)) &&
2189 INT_GET(agf->agf_freeblks, ARCH_CONVERT) <=
2190 INT_GET(agf->agf_length, ARCH_CONVERT) &&
2191 INT_GET(agf->agf_flfirst, ARCH_CONVERT) < XFS_AGFL_SIZE(mp) &&
2192 INT_GET(agf->agf_fllast, ARCH_CONVERT) < XFS_AGFL_SIZE(mp) &&
2193 INT_GET(agf->agf_flcount, ARCH_CONVERT) <= XFS_AGFL_SIZE(mp);
2194 if (unlikely(XFS_TEST_ERROR(!agf_ok, mp, XFS_ERRTAG_ALLOC_READ_AGF,
2195 XFS_RANDOM_ALLOC_READ_AGF))) {
2196 XFS_CORRUPTION_ERROR("xfs_alloc_read_agf",
2197 XFS_ERRLEVEL_LOW, mp, agf);
2198 xfs_trans_brelse(tp, bp);
2199 return XFS_ERROR(EFSCORRUPTED);
2200 }
2201 pag = &mp->m_perag[agno];
2202 if (!pag->pagf_init) {
2203 pag->pagf_freeblks = INT_GET(agf->agf_freeblks, ARCH_CONVERT);
2204 pag->pagf_flcount = INT_GET(agf->agf_flcount, ARCH_CONVERT);
2205 pag->pagf_longest = INT_GET(agf->agf_longest, ARCH_CONVERT);
2206 pag->pagf_levels[XFS_BTNUM_BNOi] =
2207 INT_GET(agf->agf_levels[XFS_BTNUM_BNOi], ARCH_CONVERT);
2208 pag->pagf_levels[XFS_BTNUM_CNTi] =
2209 INT_GET(agf->agf_levels[XFS_BTNUM_CNTi], ARCH_CONVERT);
2210 spinlock_init(&pag->pagb_lock, "xfspagb");
2211 pag->pagb_list = kmem_zalloc(XFS_PAGB_NUM_SLOTS *
2212 sizeof(xfs_perag_busy_t), KM_SLEEP);
2213 pag->pagf_init = 1;
2214 }
2215 #ifdef DEBUG
2216 else if (!XFS_FORCED_SHUTDOWN(mp)) {
2217 ASSERT(pag->pagf_freeblks == INT_GET(agf->agf_freeblks, ARCH_CONVERT));
2218 ASSERT(pag->pagf_flcount == INT_GET(agf->agf_flcount, ARCH_CONVERT));
2219 ASSERT(pag->pagf_longest == INT_GET(agf->agf_longest, ARCH_CONVERT));
2220 ASSERT(pag->pagf_levels[XFS_BTNUM_BNOi] ==
2221 INT_GET(agf->agf_levels[XFS_BTNUM_BNOi], ARCH_CONVERT));
2222 ASSERT(pag->pagf_levels[XFS_BTNUM_CNTi] ==
2223 INT_GET(agf->agf_levels[XFS_BTNUM_CNTi], ARCH_CONVERT));
2224 }
2225 #endif
2226 XFS_BUF_SET_VTYPE_REF(bp, B_FS_AGF, XFS_AGF_REF);
2227 *bpp = bp;
2228 return 0;
2229 }
2230
2231 /*
2232 * Allocate an extent (variable-size).
2233 * Depending on the allocation type, we either look in a single allocation
2234 * group or loop over the allocation groups to find the result.
2235 */
2236 int /* error */
2237 xfs_alloc_vextent(
2238 xfs_alloc_arg_t *args) /* allocation argument structure */
2239 {
2240 xfs_agblock_t agsize; /* allocation group size */
2241 int error;
2242 int flags; /* XFS_ALLOC_FLAG_... locking flags */
2243 #ifdef XFS_ALLOC_TRACE
2244 static char fname[] = "xfs_alloc_vextent";
2245 #endif
2246 xfs_extlen_t minleft;/* minimum left value, temp copy */
2247 xfs_mount_t *mp; /* mount structure pointer */
2248 xfs_agnumber_t sagno; /* starting allocation group number */
2249 xfs_alloctype_t type; /* input allocation type */
2250 int bump_rotor = 0;
2251 int no_min = 0;
2252 xfs_agnumber_t rotorstep = xfs_rotorstep; /* inode32 agf stepper */
2253
2254 mp = args->mp;
2255 type = args->otype = args->type;
2256 args->agbno = NULLAGBLOCK;
2257 /*
2258 * Just fix this up, for the case where the last a.g. is shorter
2259 * (or there's only one a.g.) and the caller couldn't easily figure
2260 * that out (xfs_bmap_alloc).
2261 */
2262 agsize = mp->m_sb.sb_agblocks;
2263 if (args->maxlen > agsize)
2264 args->maxlen = agsize;
2265 if (args->alignment == 0)
2266 args->alignment = 1;
2267 ASSERT(XFS_FSB_TO_AGNO(mp, args->fsbno) < mp->m_sb.sb_agcount);
2268 ASSERT(XFS_FSB_TO_AGBNO(mp, args->fsbno) < agsize);
2269 ASSERT(args->minlen <= args->maxlen);
2270 ASSERT(args->minlen <= agsize);
2271 ASSERT(args->mod < args->prod);
2272 if (XFS_FSB_TO_AGNO(mp, args->fsbno) >= mp->m_sb.sb_agcount ||
2273 XFS_FSB_TO_AGBNO(mp, args->fsbno) >= agsize ||
2274 args->minlen > args->maxlen || args->minlen > agsize ||
2275 args->mod >= args->prod) {
2276 args->fsbno = NULLFSBLOCK;
2277 TRACE_ALLOC("badargs", args);
2278 return 0;
2279 }
2280 minleft = args->minleft;
2281
2282 switch (type) {
2283 case XFS_ALLOCTYPE_THIS_AG:
2284 case XFS_ALLOCTYPE_NEAR_BNO:
2285 case XFS_ALLOCTYPE_THIS_BNO:
2286 /*
2287 * These three force us into a single a.g.
2288 */
2289 args->agno = XFS_FSB_TO_AGNO(mp, args->fsbno);
2290 down_read(&mp->m_peraglock);
2291 args->pag = &mp->m_perag[args->agno];
2292 args->minleft = 0;
2293 error = xfs_alloc_fix_freelist(args, 0);
2294 args->minleft = minleft;
2295 if (error) {
2296 TRACE_ALLOC("nofix", args);
2297 goto error0;
2298 }
2299 if (!args->agbp) {
2300 up_read(&mp->m_peraglock);
2301 TRACE_ALLOC("noagbp", args);
2302 break;
2303 }
2304 args->agbno = XFS_FSB_TO_AGBNO(mp, args->fsbno);
2305 if ((error = xfs_alloc_ag_vextent(args)))
2306 goto error0;
2307 up_read(&mp->m_peraglock);
2308 break;
2309 case XFS_ALLOCTYPE_START_BNO:
2310 /*
2311 * Try near allocation first, then anywhere-in-ag after
2312 * the first a.g. fails.
2313 */
2314 if ((args->userdata == XFS_ALLOC_INITIAL_USER_DATA) &&
2315 (mp->m_flags & XFS_MOUNT_32BITINODES)) {
2316 args->fsbno = XFS_AGB_TO_FSB(mp,
2317 ((mp->m_agfrotor / rotorstep) %
2318 mp->m_sb.sb_agcount), 0);
2319 bump_rotor = 1;
2320 }
2321 args->agbno = XFS_FSB_TO_AGBNO(mp, args->fsbno);
2322 args->type = XFS_ALLOCTYPE_NEAR_BNO;
2323 /* FALLTHROUGH */
2324 case XFS_ALLOCTYPE_ANY_AG:
2325 case XFS_ALLOCTYPE_START_AG:
2326 case XFS_ALLOCTYPE_FIRST_AG:
2327 /*
2328 * Rotate through the allocation groups looking for a winner.
2329 */
2330 if (type == XFS_ALLOCTYPE_ANY_AG) {
2331 /*
2332 * Start with the last place we left off.
2333 */
2334 args->agno = sagno = (mp->m_agfrotor / rotorstep) %
2335 mp->m_sb.sb_agcount;
2336 args->type = XFS_ALLOCTYPE_THIS_AG;
2337 flags = XFS_ALLOC_FLAG_TRYLOCK;
2338 } else if (type == XFS_ALLOCTYPE_FIRST_AG) {
2339 /*
2340 * Start with allocation group given by bno.
2341 */
2342 args->agno = XFS_FSB_TO_AGNO(mp, args->fsbno);
2343 args->type = XFS_ALLOCTYPE_THIS_AG;
2344 sagno = 0;
2345 flags = 0;
2346 } else {
2347 if (type == XFS_ALLOCTYPE_START_AG)
2348 args->type = XFS_ALLOCTYPE_THIS_AG;
2349 /*
2350 * Start with the given allocation group.
2351 */
2352 args->agno = sagno = XFS_FSB_TO_AGNO(mp, args->fsbno);
2353 flags = XFS_ALLOC_FLAG_TRYLOCK;
2354 }
2355 /*
2356 * Loop over allocation groups twice; first time with
2357 * trylock set, second time without.
2358 */
2359 down_read(&mp->m_peraglock);
2360 for (;;) {
2361 args->pag = &mp->m_perag[args->agno];
2362 if (no_min) args->minleft = 0;
2363 error = xfs_alloc_fix_freelist(args, flags);
2364 args->minleft = minleft;
2365 if (error) {
2366 TRACE_ALLOC("nofix", args);
2367 goto error0;
2368 }
2369 /*
2370 * If we get a buffer back then the allocation will fly.
2371 */
2372 if (args->agbp) {
2373 if ((error = xfs_alloc_ag_vextent(args)))
2374 goto error0;
2375 break;
2376 }
2377 TRACE_ALLOC("loopfailed", args);
2378 /*
2379 * Didn't work, figure out the next iteration.
2380 */
2381 if (args->agno == sagno &&
2382 type == XFS_ALLOCTYPE_START_BNO)
2383 args->type = XFS_ALLOCTYPE_THIS_AG;
2384 if (++(args->agno) == mp->m_sb.sb_agcount)
2385 args->agno = 0;
2386 /*
2387 * Reached the starting a.g., must either be done
2388 * or switch to non-trylock mode.
2389 */
2390 if (args->agno == sagno) {
2391 if (no_min == 1) {
2392 args->agbno = NULLAGBLOCK;
2393 TRACE_ALLOC("allfailed", args);
2394 break;
2395 }
2396 if (flags == 0) {
2397 no_min = 1;
2398 } else {
2399 flags = 0;
2400 if (type == XFS_ALLOCTYPE_START_BNO) {
2401 args->agbno = XFS_FSB_TO_AGBNO(mp,
2402 args->fsbno);
2403 args->type = XFS_ALLOCTYPE_NEAR_BNO;
2404 }
2405 }
2406 }
2407 }
2408 up_read(&mp->m_peraglock);
2409 if (bump_rotor || (type == XFS_ALLOCTYPE_ANY_AG)) {
2410 if (args->agno == sagno)
2411 mp->m_agfrotor = (mp->m_agfrotor + 1) %
2412 (mp->m_sb.sb_agcount * rotorstep);
2413 else
2414 mp->m_agfrotor = (args->agno * rotorstep + 1) %
2415 (mp->m_sb.sb_agcount * rotorstep);
2416 }
2417 break;
2418 default:
2419 ASSERT(0);
2420 /* NOTREACHED */
2421 }
2422 if (args->agbno == NULLAGBLOCK)
2423 args->fsbno = NULLFSBLOCK;
2424 else {
2425 args->fsbno = XFS_AGB_TO_FSB(mp, args->agno, args->agbno);
2426 #ifdef DEBUG
2427 ASSERT(args->len >= args->minlen);
2428 ASSERT(args->len <= args->maxlen);
2429 ASSERT(args->agbno % args->alignment == 0);
2430 XFS_AG_CHECK_DADDR(mp, XFS_FSB_TO_DADDR(mp, args->fsbno),
2431 args->len);
2432 #endif
2433 }
2434 return 0;
2435 error0:
2436 up_read(&mp->m_peraglock);
2437 return error;
2438 }
2439
2440 /*
2441 * Free an extent.
2442 * Just break up the extent address and hand off to xfs_free_ag_extent
2443 * after fixing up the freelist.
2444 */
2445 int /* error */
2446 xfs_free_extent(
2447 xfs_trans_t *tp, /* transaction pointer */
2448 xfs_fsblock_t bno, /* starting block number of extent */
2449 xfs_extlen_t len) /* length of extent */
2450 {
2451 #ifdef DEBUG
2452 xfs_agf_t *agf; /* a.g. freespace header */
2453 #endif
2454 xfs_alloc_arg_t args; /* allocation argument structure */
2455 int error;
2456
2457 ASSERT(len != 0);
2458 args.tp = tp;
2459 args.mp = tp->t_mountp;
2460 args.agno = XFS_FSB_TO_AGNO(args.mp, bno);
2461 ASSERT(args.agno < args.mp->m_sb.sb_agcount);
2462 args.agbno = XFS_FSB_TO_AGBNO(args.mp, bno);
2463 args.alignment = 1;
2464 args.minlen = args.minleft = args.minalignslop = 0;
2465 down_read(&args.mp->m_peraglock);
2466 args.pag = &args.mp->m_perag[args.agno];
2467 if ((error = xfs_alloc_fix_freelist(&args, 0)))
2468 goto error0;
2469 #ifdef DEBUG
2470 ASSERT(args.agbp != NULL);
2471 agf = XFS_BUF_TO_AGF(args.agbp);
2472 ASSERT(args.agbno + len <= INT_GET(agf->agf_length, ARCH_CONVERT));
2473 #endif
2474 error = xfs_free_ag_extent(tp, args.agbp, args.agno, args.agbno,
2475 len, 0);
2476 error0:
2477 up_read(&args.mp->m_peraglock);
2478 return error;
2479 }
2480
2481
2482 /*
2483 * AG Busy list management
2484 * The busy list contains block ranges that have been freed but whose
2485 * transacations have not yet hit disk. If any block listed in a busy
2486 * list is reused, the transaction that freed it must be forced to disk
2487 * before continuing to use the block.
2488 *
2489 * xfs_alloc_mark_busy - add to the per-ag busy list
2490 * xfs_alloc_clear_busy - remove an item from the per-ag busy list
2491 */
2492 void
2493 xfs_alloc_mark_busy(xfs_trans_t *tp,
2494 xfs_agnumber_t agno,
2495 xfs_agblock_t bno,
2496 xfs_extlen_t len)
2497 {
2498 xfs_mount_t *mp;
2499 xfs_perag_busy_t *bsy;
2500 int n;
2501 SPLDECL(s);
2502
2503 mp = tp->t_mountp;
2504 s = mutex_spinlock(&mp->m_perag[agno].pagb_lock);
2505
2506 /* search pagb_list for an open slot */
2507 for (bsy = mp->m_perag[agno].pagb_list, n = 0;
2508 n < XFS_PAGB_NUM_SLOTS;
2509 bsy++, n++) {
2510 if (bsy->busy_tp == NULL) {
2511 break;
2512 }
2513 }
2514
2515 if (n < XFS_PAGB_NUM_SLOTS) {
2516 bsy = &mp->m_perag[agno].pagb_list[n];
2517 mp->m_perag[agno].pagb_count++;
2518 TRACE_BUSY("xfs_alloc_mark_busy", "got", agno, bno, len, n, tp);
2519 bsy->busy_start = bno;
2520 bsy->busy_length = len;
2521 bsy->busy_tp = tp;
2522 xfs_trans_add_busy(tp, agno, n);
2523 } else {
2524 TRACE_BUSY("xfs_alloc_mark_busy", "FULL", agno, bno, len, -1, tp);
2525 /*
2526 * The busy list is full! Since it is now not possible to
2527 * track the free block, make this a synchronous transaction
2528 * to insure that the block is not reused before this
2529 * transaction commits.
2530 */
2531 xfs_trans_set_sync(tp);
2532 }
2533
2534 mutex_spinunlock(&mp->m_perag[agno].pagb_lock, s);
2535 }
2536
2537 void
2538 xfs_alloc_clear_busy(xfs_trans_t *tp,
2539 xfs_agnumber_t agno,
2540 int idx)
2541 {
2542 xfs_mount_t *mp;
2543 xfs_perag_busy_t *list;
2544 SPLDECL(s);
2545
2546 mp = tp->t_mountp;
2547
2548 s = mutex_spinlock(&mp->m_perag[agno].pagb_lock);
2549 list = mp->m_perag[agno].pagb_list;
2550
2551 ASSERT(idx < XFS_PAGB_NUM_SLOTS);
2552 if (list[idx].busy_tp == tp) {
2553 TRACE_UNBUSY("xfs_alloc_clear_busy", "found", agno, idx, tp);
2554 list[idx].busy_tp = NULL;
2555 mp->m_perag[agno].pagb_count--;
2556 } else {
2557 TRACE_UNBUSY("xfs_alloc_clear_busy", "missing", agno, idx, tp);
2558 }
2559
2560 mutex_spinunlock(&mp->m_perag[agno].pagb_lock, s);
2561 }
2562
2563
2564 /*
2565 * returns non-zero if any of (agno,bno):len is in a busy list
2566 */
2567 STATIC int
2568 xfs_alloc_search_busy(xfs_trans_t *tp,
2569 xfs_agnumber_t agno,
2570 xfs_agblock_t bno,
2571 xfs_extlen_t len)
2572 {
2573 xfs_mount_t *mp;
2574 xfs_perag_busy_t *bsy;
2575 int n;
2576 xfs_agblock_t uend, bend;
2577 xfs_lsn_t lsn;
2578 int cnt;
2579 SPLDECL(s);
2580
2581 mp = tp->t_mountp;
2582
2583 s = mutex_spinlock(&mp->m_perag[agno].pagb_lock);
2584 cnt = mp->m_perag[agno].pagb_count;
2585
2586 uend = bno + len - 1;
2587
2588 /* search pagb_list for this slot, skipping open slots */
2589 for (bsy = mp->m_perag[agno].pagb_list, n = 0;
2590 cnt; bsy++, n++) {
2591
2592 /*
2593 * (start1,length1) within (start2, length2)
2594 */
2595 if (bsy->busy_tp != NULL) {
2596 bend = bsy->busy_start + bsy->busy_length - 1;
2597 if ((bno > bend) ||
2598 (uend < bsy->busy_start)) {
2599 cnt--;
2600 } else {
2601 TRACE_BUSYSEARCH("xfs_alloc_search_busy",
2602 "found1", agno, bno, len, n,
2603 tp);
2604 break;
2605 }
2606 }
2607 }
2608
2609 /*
2610 * If a block was found, force the log through the LSN of the
2611 * transaction that freed the block
2612 */
2613 if (cnt) {
2614 TRACE_BUSYSEARCH("xfs_alloc_search_busy", "found", agno, bno, len, n, tp);
2615 lsn = bsy->busy_tp->t_commit_lsn;
2616 mutex_spinunlock(&mp->m_perag[agno].pagb_lock, s);
2617 xfs_log_force(mp, lsn, XFS_LOG_FORCE|XFS_LOG_SYNC);
2618 } else {
2619 TRACE_BUSYSEARCH("xfs_alloc_search_busy", "not-found", agno, bno, len, n, tp);
2620 n = -1;
2621 mutex_spinunlock(&mp->m_perag[agno].pagb_lock, s);
2622 }
2623
2624 return n;
2625 }
kernel source for telekom puls (alcatel/mediatek)