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1da177e4 | 1 | /* |
7b718769 NS |
2 | * Copyright (c) 2000-2002,2005 Silicon Graphics, Inc. |
3 | * All Rights Reserved. | |
1da177e4 | 4 | * |
7b718769 NS |
5 | * This program is free software; you can redistribute it and/or |
6 | * modify it under the terms of the GNU General Public License as | |
1da177e4 LT |
7 | * published by the Free Software Foundation. |
8 | * | |
7b718769 NS |
9 | * This program is distributed in the hope that it would be useful, |
10 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
11 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
12 | * GNU General Public License for more details. | |
1da177e4 | 13 | * |
7b718769 NS |
14 | * You should have received a copy of the GNU General Public License |
15 | * along with this program; if not, write the Free Software Foundation, | |
16 | * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA | |
1da177e4 | 17 | */ |
1da177e4 | 18 | #include "xfs.h" |
a844f451 | 19 | #include "xfs_fs.h" |
1da177e4 | 20 | #include "xfs_types.h" |
a844f451 | 21 | #include "xfs_bit.h" |
1da177e4 | 22 | #include "xfs_log.h" |
a844f451 | 23 | #include "xfs_inum.h" |
1da177e4 LT |
24 | #include "xfs_trans.h" |
25 | #include "xfs_sb.h" | |
26 | #include "xfs_ag.h" | |
1da177e4 | 27 | #include "xfs_mount.h" |
1da177e4 | 28 | #include "xfs_bmap_btree.h" |
a844f451 | 29 | #include "xfs_alloc_btree.h" |
1da177e4 | 30 | #include "xfs_ialloc_btree.h" |
a844f451 NS |
31 | #include "xfs_dinode.h" |
32 | #include "xfs_inode.h" | |
1da177e4 | 33 | #include "xfs_btree.h" |
1da177e4 | 34 | #include "xfs_alloc.h" |
1da177e4 | 35 | #include "xfs_error.h" |
0b1b213f | 36 | #include "xfs_trace.h" |
1da177e4 LT |
37 | |
38 | ||
39 | #define XFS_ABSDIFF(a,b) (((a) <= (b)) ? ((b) - (a)) : ((a) - (b))) | |
40 | ||
41 | #define XFSA_FIXUP_BNO_OK 1 | |
42 | #define XFSA_FIXUP_CNT_OK 2 | |
43 | ||
1da177e4 LT |
44 | STATIC int xfs_alloc_ag_vextent_exact(xfs_alloc_arg_t *); |
45 | STATIC int xfs_alloc_ag_vextent_near(xfs_alloc_arg_t *); | |
46 | STATIC int xfs_alloc_ag_vextent_size(xfs_alloc_arg_t *); | |
47 | STATIC int xfs_alloc_ag_vextent_small(xfs_alloc_arg_t *, | |
e26f0501 CH |
48 | xfs_btree_cur_t *, xfs_agblock_t *, xfs_extlen_t *, int *); |
49 | STATIC void xfs_alloc_busy_trim(struct xfs_alloc_arg *, | |
50 | xfs_agblock_t, xfs_extlen_t, xfs_agblock_t *, xfs_extlen_t *); | |
1da177e4 | 51 | |
fe033cc8 CH |
52 | /* |
53 | * Lookup the record equal to [bno, len] in the btree given by cur. | |
54 | */ | |
55 | STATIC int /* error */ | |
56 | xfs_alloc_lookup_eq( | |
57 | struct xfs_btree_cur *cur, /* btree cursor */ | |
58 | xfs_agblock_t bno, /* starting block of extent */ | |
59 | xfs_extlen_t len, /* length of extent */ | |
60 | int *stat) /* success/failure */ | |
61 | { | |
62 | cur->bc_rec.a.ar_startblock = bno; | |
63 | cur->bc_rec.a.ar_blockcount = len; | |
64 | return xfs_btree_lookup(cur, XFS_LOOKUP_EQ, stat); | |
65 | } | |
66 | ||
67 | /* | |
68 | * Lookup the first record greater than or equal to [bno, len] | |
69 | * in the btree given by cur. | |
70 | */ | |
71 | STATIC int /* error */ | |
72 | xfs_alloc_lookup_ge( | |
73 | struct xfs_btree_cur *cur, /* btree cursor */ | |
74 | xfs_agblock_t bno, /* starting block of extent */ | |
75 | xfs_extlen_t len, /* length of extent */ | |
76 | int *stat) /* success/failure */ | |
77 | { | |
78 | cur->bc_rec.a.ar_startblock = bno; | |
79 | cur->bc_rec.a.ar_blockcount = len; | |
80 | return xfs_btree_lookup(cur, XFS_LOOKUP_GE, stat); | |
81 | } | |
82 | ||
83 | /* | |
84 | * Lookup the first record less than or equal to [bno, len] | |
85 | * in the btree given by cur. | |
86 | */ | |
a46db608 | 87 | int /* error */ |
fe033cc8 CH |
88 | xfs_alloc_lookup_le( |
89 | struct xfs_btree_cur *cur, /* btree cursor */ | |
90 | xfs_agblock_t bno, /* starting block of extent */ | |
91 | xfs_extlen_t len, /* length of extent */ | |
92 | int *stat) /* success/failure */ | |
93 | { | |
94 | cur->bc_rec.a.ar_startblock = bno; | |
95 | cur->bc_rec.a.ar_blockcount = len; | |
96 | return xfs_btree_lookup(cur, XFS_LOOKUP_LE, stat); | |
97 | } | |
98 | ||
278d0ca1 CH |
99 | /* |
100 | * Update the record referred to by cur to the value given | |
101 | * by [bno, len]. | |
102 | * This either works (return 0) or gets an EFSCORRUPTED error. | |
103 | */ | |
104 | STATIC int /* error */ | |
105 | xfs_alloc_update( | |
106 | struct xfs_btree_cur *cur, /* btree cursor */ | |
107 | xfs_agblock_t bno, /* starting block of extent */ | |
108 | xfs_extlen_t len) /* length of extent */ | |
109 | { | |
110 | union xfs_btree_rec rec; | |
111 | ||
112 | rec.alloc.ar_startblock = cpu_to_be32(bno); | |
113 | rec.alloc.ar_blockcount = cpu_to_be32(len); | |
114 | return xfs_btree_update(cur, &rec); | |
115 | } | |
fe033cc8 | 116 | |
8cc938fe CH |
117 | /* |
118 | * Get the data from the pointed-to record. | |
119 | */ | |
a46db608 | 120 | int /* error */ |
8cc938fe CH |
121 | xfs_alloc_get_rec( |
122 | struct xfs_btree_cur *cur, /* btree cursor */ | |
123 | xfs_agblock_t *bno, /* output: starting block of extent */ | |
124 | xfs_extlen_t *len, /* output: length of extent */ | |
125 | int *stat) /* output: success/failure */ | |
126 | { | |
127 | union xfs_btree_rec *rec; | |
128 | int error; | |
129 | ||
130 | error = xfs_btree_get_rec(cur, &rec, stat); | |
131 | if (!error && *stat == 1) { | |
132 | *bno = be32_to_cpu(rec->alloc.ar_startblock); | |
133 | *len = be32_to_cpu(rec->alloc.ar_blockcount); | |
134 | } | |
135 | return error; | |
136 | } | |
137 | ||
1da177e4 LT |
138 | /* |
139 | * Compute aligned version of the found extent. | |
140 | * Takes alignment and min length into account. | |
141 | */ | |
12375c82 | 142 | STATIC void |
1da177e4 | 143 | xfs_alloc_compute_aligned( |
86fa8af6 | 144 | xfs_alloc_arg_t *args, /* allocation argument structure */ |
1da177e4 LT |
145 | xfs_agblock_t foundbno, /* starting block in found extent */ |
146 | xfs_extlen_t foundlen, /* length in found extent */ | |
1da177e4 LT |
147 | xfs_agblock_t *resbno, /* result block number */ |
148 | xfs_extlen_t *reslen) /* result length */ | |
149 | { | |
150 | xfs_agblock_t bno; | |
1da177e4 LT |
151 | xfs_extlen_t len; |
152 | ||
e26f0501 CH |
153 | /* Trim busy sections out of found extent */ |
154 | xfs_alloc_busy_trim(args, foundbno, foundlen, &bno, &len); | |
155 | ||
156 | if (args->alignment > 1 && len >= args->minlen) { | |
157 | xfs_agblock_t aligned_bno = roundup(bno, args->alignment); | |
158 | xfs_extlen_t diff = aligned_bno - bno; | |
159 | ||
160 | *resbno = aligned_bno; | |
161 | *reslen = diff >= len ? 0 : len - diff; | |
1da177e4 | 162 | } else { |
e26f0501 CH |
163 | *resbno = bno; |
164 | *reslen = len; | |
1da177e4 | 165 | } |
1da177e4 LT |
166 | } |
167 | ||
168 | /* | |
169 | * Compute best start block and diff for "near" allocations. | |
170 | * freelen >= wantlen already checked by caller. | |
171 | */ | |
172 | STATIC xfs_extlen_t /* difference value (absolute) */ | |
173 | xfs_alloc_compute_diff( | |
174 | xfs_agblock_t wantbno, /* target starting block */ | |
175 | xfs_extlen_t wantlen, /* target length */ | |
176 | xfs_extlen_t alignment, /* target alignment */ | |
177 | xfs_agblock_t freebno, /* freespace's starting block */ | |
178 | xfs_extlen_t freelen, /* freespace's length */ | |
179 | xfs_agblock_t *newbnop) /* result: best start block from free */ | |
180 | { | |
181 | xfs_agblock_t freeend; /* end of freespace extent */ | |
182 | xfs_agblock_t newbno1; /* return block number */ | |
183 | xfs_agblock_t newbno2; /* other new block number */ | |
184 | xfs_extlen_t newlen1=0; /* length with newbno1 */ | |
185 | xfs_extlen_t newlen2=0; /* length with newbno2 */ | |
186 | xfs_agblock_t wantend; /* end of target extent */ | |
187 | ||
188 | ASSERT(freelen >= wantlen); | |
189 | freeend = freebno + freelen; | |
190 | wantend = wantbno + wantlen; | |
191 | if (freebno >= wantbno) { | |
192 | if ((newbno1 = roundup(freebno, alignment)) >= freeend) | |
193 | newbno1 = NULLAGBLOCK; | |
194 | } else if (freeend >= wantend && alignment > 1) { | |
195 | newbno1 = roundup(wantbno, alignment); | |
196 | newbno2 = newbno1 - alignment; | |
197 | if (newbno1 >= freeend) | |
198 | newbno1 = NULLAGBLOCK; | |
199 | else | |
200 | newlen1 = XFS_EXTLEN_MIN(wantlen, freeend - newbno1); | |
201 | if (newbno2 < freebno) | |
202 | newbno2 = NULLAGBLOCK; | |
203 | else | |
204 | newlen2 = XFS_EXTLEN_MIN(wantlen, freeend - newbno2); | |
205 | if (newbno1 != NULLAGBLOCK && newbno2 != NULLAGBLOCK) { | |
206 | if (newlen1 < newlen2 || | |
207 | (newlen1 == newlen2 && | |
208 | XFS_ABSDIFF(newbno1, wantbno) > | |
209 | XFS_ABSDIFF(newbno2, wantbno))) | |
210 | newbno1 = newbno2; | |
211 | } else if (newbno2 != NULLAGBLOCK) | |
212 | newbno1 = newbno2; | |
213 | } else if (freeend >= wantend) { | |
214 | newbno1 = wantbno; | |
215 | } else if (alignment > 1) { | |
216 | newbno1 = roundup(freeend - wantlen, alignment); | |
217 | if (newbno1 > freeend - wantlen && | |
218 | newbno1 - alignment >= freebno) | |
219 | newbno1 -= alignment; | |
220 | else if (newbno1 >= freeend) | |
221 | newbno1 = NULLAGBLOCK; | |
222 | } else | |
223 | newbno1 = freeend - wantlen; | |
224 | *newbnop = newbno1; | |
225 | return newbno1 == NULLAGBLOCK ? 0 : XFS_ABSDIFF(newbno1, wantbno); | |
226 | } | |
227 | ||
228 | /* | |
229 | * Fix up the length, based on mod and prod. | |
230 | * len should be k * prod + mod for some k. | |
231 | * If len is too small it is returned unchanged. | |
232 | * If len hits maxlen it is left alone. | |
233 | */ | |
234 | STATIC void | |
235 | xfs_alloc_fix_len( | |
236 | xfs_alloc_arg_t *args) /* allocation argument structure */ | |
237 | { | |
238 | xfs_extlen_t k; | |
239 | xfs_extlen_t rlen; | |
240 | ||
241 | ASSERT(args->mod < args->prod); | |
242 | rlen = args->len; | |
243 | ASSERT(rlen >= args->minlen); | |
244 | ASSERT(rlen <= args->maxlen); | |
245 | if (args->prod <= 1 || rlen < args->mod || rlen == args->maxlen || | |
246 | (args->mod == 0 && rlen < args->prod)) | |
247 | return; | |
248 | k = rlen % args->prod; | |
249 | if (k == args->mod) | |
250 | return; | |
251 | if (k > args->mod) { | |
252 | if ((int)(rlen = rlen - k - args->mod) < (int)args->minlen) | |
253 | return; | |
254 | } else { | |
255 | if ((int)(rlen = rlen - args->prod - (args->mod - k)) < | |
256 | (int)args->minlen) | |
257 | return; | |
258 | } | |
259 | ASSERT(rlen >= args->minlen); | |
260 | ASSERT(rlen <= args->maxlen); | |
261 | args->len = rlen; | |
262 | } | |
263 | ||
264 | /* | |
265 | * Fix up length if there is too little space left in the a.g. | |
266 | * Return 1 if ok, 0 if too little, should give up. | |
267 | */ | |
268 | STATIC int | |
269 | xfs_alloc_fix_minleft( | |
270 | xfs_alloc_arg_t *args) /* allocation argument structure */ | |
271 | { | |
272 | xfs_agf_t *agf; /* a.g. freelist header */ | |
273 | int diff; /* free space difference */ | |
274 | ||
275 | if (args->minleft == 0) | |
276 | return 1; | |
277 | agf = XFS_BUF_TO_AGF(args->agbp); | |
16259e7d | 278 | diff = be32_to_cpu(agf->agf_freeblks) |
1da177e4 LT |
279 | - args->len - args->minleft; |
280 | if (diff >= 0) | |
281 | return 1; | |
282 | args->len += diff; /* shrink the allocated space */ | |
283 | if (args->len >= args->minlen) | |
284 | return 1; | |
285 | args->agbno = NULLAGBLOCK; | |
286 | return 0; | |
287 | } | |
288 | ||
289 | /* | |
290 | * Update the two btrees, logically removing from freespace the extent | |
291 | * starting at rbno, rlen blocks. The extent is contained within the | |
292 | * actual (current) free extent fbno for flen blocks. | |
293 | * Flags are passed in indicating whether the cursors are set to the | |
294 | * relevant records. | |
295 | */ | |
296 | STATIC int /* error code */ | |
297 | xfs_alloc_fixup_trees( | |
298 | xfs_btree_cur_t *cnt_cur, /* cursor for by-size btree */ | |
299 | xfs_btree_cur_t *bno_cur, /* cursor for by-block btree */ | |
300 | xfs_agblock_t fbno, /* starting block of free extent */ | |
301 | xfs_extlen_t flen, /* length of free extent */ | |
302 | xfs_agblock_t rbno, /* starting block of returned extent */ | |
303 | xfs_extlen_t rlen, /* length of returned extent */ | |
304 | int flags) /* flags, XFSA_FIXUP_... */ | |
305 | { | |
306 | int error; /* error code */ | |
307 | int i; /* operation results */ | |
308 | xfs_agblock_t nfbno1; /* first new free startblock */ | |
309 | xfs_agblock_t nfbno2; /* second new free startblock */ | |
310 | xfs_extlen_t nflen1=0; /* first new free length */ | |
311 | xfs_extlen_t nflen2=0; /* second new free length */ | |
312 | ||
313 | /* | |
314 | * Look up the record in the by-size tree if necessary. | |
315 | */ | |
316 | if (flags & XFSA_FIXUP_CNT_OK) { | |
317 | #ifdef DEBUG | |
318 | if ((error = xfs_alloc_get_rec(cnt_cur, &nfbno1, &nflen1, &i))) | |
319 | return error; | |
320 | XFS_WANT_CORRUPTED_RETURN( | |
321 | i == 1 && nfbno1 == fbno && nflen1 == flen); | |
322 | #endif | |
323 | } else { | |
324 | if ((error = xfs_alloc_lookup_eq(cnt_cur, fbno, flen, &i))) | |
325 | return error; | |
326 | XFS_WANT_CORRUPTED_RETURN(i == 1); | |
327 | } | |
328 | /* | |
329 | * Look up the record in the by-block tree if necessary. | |
330 | */ | |
331 | if (flags & XFSA_FIXUP_BNO_OK) { | |
332 | #ifdef DEBUG | |
333 | if ((error = xfs_alloc_get_rec(bno_cur, &nfbno1, &nflen1, &i))) | |
334 | return error; | |
335 | XFS_WANT_CORRUPTED_RETURN( | |
336 | i == 1 && nfbno1 == fbno && nflen1 == flen); | |
337 | #endif | |
338 | } else { | |
339 | if ((error = xfs_alloc_lookup_eq(bno_cur, fbno, flen, &i))) | |
340 | return error; | |
341 | XFS_WANT_CORRUPTED_RETURN(i == 1); | |
342 | } | |
7cc95a82 | 343 | |
1da177e4 | 344 | #ifdef DEBUG |
7cc95a82 CH |
345 | if (bno_cur->bc_nlevels == 1 && cnt_cur->bc_nlevels == 1) { |
346 | struct xfs_btree_block *bnoblock; | |
347 | struct xfs_btree_block *cntblock; | |
348 | ||
349 | bnoblock = XFS_BUF_TO_BLOCK(bno_cur->bc_bufs[0]); | |
350 | cntblock = XFS_BUF_TO_BLOCK(cnt_cur->bc_bufs[0]); | |
1da177e4 | 351 | |
7cc95a82 CH |
352 | XFS_WANT_CORRUPTED_RETURN( |
353 | bnoblock->bb_numrecs == cntblock->bb_numrecs); | |
1da177e4 LT |
354 | } |
355 | #endif | |
7cc95a82 | 356 | |
1da177e4 LT |
357 | /* |
358 | * Deal with all four cases: the allocated record is contained | |
359 | * within the freespace record, so we can have new freespace | |
360 | * at either (or both) end, or no freespace remaining. | |
361 | */ | |
362 | if (rbno == fbno && rlen == flen) | |
363 | nfbno1 = nfbno2 = NULLAGBLOCK; | |
364 | else if (rbno == fbno) { | |
365 | nfbno1 = rbno + rlen; | |
366 | nflen1 = flen - rlen; | |
367 | nfbno2 = NULLAGBLOCK; | |
368 | } else if (rbno + rlen == fbno + flen) { | |
369 | nfbno1 = fbno; | |
370 | nflen1 = flen - rlen; | |
371 | nfbno2 = NULLAGBLOCK; | |
372 | } else { | |
373 | nfbno1 = fbno; | |
374 | nflen1 = rbno - fbno; | |
375 | nfbno2 = rbno + rlen; | |
376 | nflen2 = (fbno + flen) - nfbno2; | |
377 | } | |
378 | /* | |
379 | * Delete the entry from the by-size btree. | |
380 | */ | |
91cca5df | 381 | if ((error = xfs_btree_delete(cnt_cur, &i))) |
1da177e4 LT |
382 | return error; |
383 | XFS_WANT_CORRUPTED_RETURN(i == 1); | |
384 | /* | |
385 | * Add new by-size btree entry(s). | |
386 | */ | |
387 | if (nfbno1 != NULLAGBLOCK) { | |
388 | if ((error = xfs_alloc_lookup_eq(cnt_cur, nfbno1, nflen1, &i))) | |
389 | return error; | |
390 | XFS_WANT_CORRUPTED_RETURN(i == 0); | |
4b22a571 | 391 | if ((error = xfs_btree_insert(cnt_cur, &i))) |
1da177e4 LT |
392 | return error; |
393 | XFS_WANT_CORRUPTED_RETURN(i == 1); | |
394 | } | |
395 | if (nfbno2 != NULLAGBLOCK) { | |
396 | if ((error = xfs_alloc_lookup_eq(cnt_cur, nfbno2, nflen2, &i))) | |
397 | return error; | |
398 | XFS_WANT_CORRUPTED_RETURN(i == 0); | |
4b22a571 | 399 | if ((error = xfs_btree_insert(cnt_cur, &i))) |
1da177e4 LT |
400 | return error; |
401 | XFS_WANT_CORRUPTED_RETURN(i == 1); | |
402 | } | |
403 | /* | |
404 | * Fix up the by-block btree entry(s). | |
405 | */ | |
406 | if (nfbno1 == NULLAGBLOCK) { | |
407 | /* | |
408 | * No remaining freespace, just delete the by-block tree entry. | |
409 | */ | |
91cca5df | 410 | if ((error = xfs_btree_delete(bno_cur, &i))) |
1da177e4 LT |
411 | return error; |
412 | XFS_WANT_CORRUPTED_RETURN(i == 1); | |
413 | } else { | |
414 | /* | |
415 | * Update the by-block entry to start later|be shorter. | |
416 | */ | |
417 | if ((error = xfs_alloc_update(bno_cur, nfbno1, nflen1))) | |
418 | return error; | |
419 | } | |
420 | if (nfbno2 != NULLAGBLOCK) { | |
421 | /* | |
422 | * 2 resulting free entries, need to add one. | |
423 | */ | |
424 | if ((error = xfs_alloc_lookup_eq(bno_cur, nfbno2, nflen2, &i))) | |
425 | return error; | |
426 | XFS_WANT_CORRUPTED_RETURN(i == 0); | |
4b22a571 | 427 | if ((error = xfs_btree_insert(bno_cur, &i))) |
1da177e4 LT |
428 | return error; |
429 | XFS_WANT_CORRUPTED_RETURN(i == 1); | |
430 | } | |
431 | return 0; | |
432 | } | |
433 | ||
434 | /* | |
435 | * Read in the allocation group free block array. | |
436 | */ | |
437 | STATIC int /* error */ | |
438 | xfs_alloc_read_agfl( | |
439 | xfs_mount_t *mp, /* mount point structure */ | |
440 | xfs_trans_t *tp, /* transaction pointer */ | |
441 | xfs_agnumber_t agno, /* allocation group number */ | |
442 | xfs_buf_t **bpp) /* buffer for the ag free block array */ | |
443 | { | |
444 | xfs_buf_t *bp; /* return value */ | |
445 | int error; | |
446 | ||
447 | ASSERT(agno != NULLAGNUMBER); | |
448 | error = xfs_trans_read_buf( | |
449 | mp, tp, mp->m_ddev_targp, | |
450 | XFS_AG_DADDR(mp, agno, XFS_AGFL_DADDR(mp)), | |
451 | XFS_FSS_TO_BB(mp, 1), 0, &bp); | |
452 | if (error) | |
453 | return error; | |
454 | ASSERT(bp); | |
455 | ASSERT(!XFS_BUF_GETERROR(bp)); | |
456 | XFS_BUF_SET_VTYPE_REF(bp, B_FS_AGFL, XFS_AGFL_REF); | |
457 | *bpp = bp; | |
458 | return 0; | |
459 | } | |
460 | ||
ecb6928f CH |
461 | STATIC int |
462 | xfs_alloc_update_counters( | |
463 | struct xfs_trans *tp, | |
464 | struct xfs_perag *pag, | |
465 | struct xfs_buf *agbp, | |
466 | long len) | |
467 | { | |
468 | struct xfs_agf *agf = XFS_BUF_TO_AGF(agbp); | |
469 | ||
470 | pag->pagf_freeblks += len; | |
471 | be32_add_cpu(&agf->agf_freeblks, len); | |
472 | ||
473 | xfs_trans_agblocks_delta(tp, len); | |
474 | if (unlikely(be32_to_cpu(agf->agf_freeblks) > | |
475 | be32_to_cpu(agf->agf_length))) | |
476 | return EFSCORRUPTED; | |
477 | ||
478 | xfs_alloc_log_agf(tp, agbp, XFS_AGF_FREEBLKS); | |
479 | return 0; | |
480 | } | |
481 | ||
1da177e4 LT |
482 | /* |
483 | * Allocation group level functions. | |
484 | */ | |
485 | ||
486 | /* | |
487 | * Allocate a variable extent in the allocation group agno. | |
488 | * Type and bno are used to determine where in the allocation group the | |
489 | * extent will start. | |
490 | * Extent's length (returned in *len) will be between minlen and maxlen, | |
491 | * and of the form k * prod + mod unless there's nothing that large. | |
492 | * Return the starting a.g. block, or NULLAGBLOCK if we can't do it. | |
493 | */ | |
494 | STATIC int /* error */ | |
495 | xfs_alloc_ag_vextent( | |
496 | xfs_alloc_arg_t *args) /* argument structure for allocation */ | |
497 | { | |
498 | int error=0; | |
1da177e4 LT |
499 | |
500 | ASSERT(args->minlen > 0); | |
501 | ASSERT(args->maxlen > 0); | |
502 | ASSERT(args->minlen <= args->maxlen); | |
503 | ASSERT(args->mod < args->prod); | |
504 | ASSERT(args->alignment > 0); | |
505 | /* | |
506 | * Branch to correct routine based on the type. | |
507 | */ | |
508 | args->wasfromfl = 0; | |
509 | switch (args->type) { | |
510 | case XFS_ALLOCTYPE_THIS_AG: | |
511 | error = xfs_alloc_ag_vextent_size(args); | |
512 | break; | |
513 | case XFS_ALLOCTYPE_NEAR_BNO: | |
514 | error = xfs_alloc_ag_vextent_near(args); | |
515 | break; | |
516 | case XFS_ALLOCTYPE_THIS_BNO: | |
517 | error = xfs_alloc_ag_vextent_exact(args); | |
518 | break; | |
519 | default: | |
520 | ASSERT(0); | |
521 | /* NOTREACHED */ | |
522 | } | |
ecb6928f CH |
523 | |
524 | if (error || args->agbno == NULLAGBLOCK) | |
1da177e4 | 525 | return error; |
ecb6928f CH |
526 | |
527 | ASSERT(args->len >= args->minlen); | |
528 | ASSERT(args->len <= args->maxlen); | |
529 | ASSERT(!args->wasfromfl || !args->isfl); | |
530 | ASSERT(args->agbno % args->alignment == 0); | |
531 | ||
532 | if (!args->wasfromfl) { | |
533 | error = xfs_alloc_update_counters(args->tp, args->pag, | |
534 | args->agbp, | |
535 | -((long)(args->len))); | |
536 | if (error) | |
537 | return error; | |
538 | ||
e26f0501 CH |
539 | ASSERT(!xfs_alloc_busy_search(args->mp, args->agno, |
540 | args->agbno, args->len)); | |
1da177e4 | 541 | } |
ecb6928f CH |
542 | |
543 | if (!args->isfl) { | |
544 | xfs_trans_mod_sb(args->tp, args->wasdel ? | |
545 | XFS_TRANS_SB_RES_FDBLOCKS : | |
546 | XFS_TRANS_SB_FDBLOCKS, | |
547 | -((long)(args->len))); | |
548 | } | |
549 | ||
550 | XFS_STATS_INC(xs_allocx); | |
551 | XFS_STATS_ADD(xs_allocb, args->len); | |
552 | return error; | |
1da177e4 LT |
553 | } |
554 | ||
555 | /* | |
556 | * Allocate a variable extent at exactly agno/bno. | |
557 | * Extent's length (returned in *len) will be between minlen and maxlen, | |
558 | * and of the form k * prod + mod unless there's nothing that large. | |
559 | * Return the starting a.g. block (bno), or NULLAGBLOCK if we can't do it. | |
560 | */ | |
561 | STATIC int /* error */ | |
562 | xfs_alloc_ag_vextent_exact( | |
563 | xfs_alloc_arg_t *args) /* allocation argument structure */ | |
564 | { | |
565 | xfs_btree_cur_t *bno_cur;/* by block-number btree cursor */ | |
566 | xfs_btree_cur_t *cnt_cur;/* by count btree cursor */ | |
1da177e4 LT |
567 | int error; |
568 | xfs_agblock_t fbno; /* start block of found extent */ | |
1da177e4 | 569 | xfs_extlen_t flen; /* length of found extent */ |
e26f0501 CH |
570 | xfs_agblock_t tbno; /* start block of trimmed extent */ |
571 | xfs_extlen_t tlen; /* length of trimmed extent */ | |
572 | xfs_agblock_t tend; /* end block of trimmed extent */ | |
573 | xfs_agblock_t end; /* end of allocated extent */ | |
1da177e4 | 574 | int i; /* success/failure of operation */ |
1da177e4 LT |
575 | xfs_extlen_t rlen; /* length of returned extent */ |
576 | ||
577 | ASSERT(args->alignment == 1); | |
9f9baab3 | 578 | |
1da177e4 LT |
579 | /* |
580 | * Allocate/initialize a cursor for the by-number freespace btree. | |
581 | */ | |
561f7d17 | 582 | bno_cur = xfs_allocbt_init_cursor(args->mp, args->tp, args->agbp, |
9f9baab3 CH |
583 | args->agno, XFS_BTNUM_BNO); |
584 | ||
1da177e4 LT |
585 | /* |
586 | * Lookup bno and minlen in the btree (minlen is irrelevant, really). | |
587 | * Look for the closest free block <= bno, it must contain bno | |
588 | * if any free block does. | |
589 | */ | |
9f9baab3 CH |
590 | error = xfs_alloc_lookup_le(bno_cur, args->agbno, args->minlen, &i); |
591 | if (error) | |
1da177e4 | 592 | goto error0; |
9f9baab3 CH |
593 | if (!i) |
594 | goto not_found; | |
595 | ||
1da177e4 LT |
596 | /* |
597 | * Grab the freespace record. | |
598 | */ | |
9f9baab3 CH |
599 | error = xfs_alloc_get_rec(bno_cur, &fbno, &flen, &i); |
600 | if (error) | |
1da177e4 LT |
601 | goto error0; |
602 | XFS_WANT_CORRUPTED_GOTO(i == 1, error0); | |
603 | ASSERT(fbno <= args->agbno); | |
9f9baab3 | 604 | |
1da177e4 | 605 | /* |
e26f0501 | 606 | * Check for overlapping busy extents. |
1da177e4 | 607 | */ |
e26f0501 CH |
608 | xfs_alloc_busy_trim(args, fbno, flen, &tbno, &tlen); |
609 | ||
610 | /* | |
611 | * Give up if the start of the extent is busy, or the freespace isn't | |
612 | * long enough for the minimum request. | |
613 | */ | |
614 | if (tbno > args->agbno) | |
615 | goto not_found; | |
616 | if (tlen < args->minlen) | |
617 | goto not_found; | |
618 | tend = tbno + tlen; | |
619 | if (tend < args->agbno + args->minlen) | |
9f9baab3 CH |
620 | goto not_found; |
621 | ||
1da177e4 LT |
622 | /* |
623 | * End of extent will be smaller of the freespace end and the | |
624 | * maximal requested end. | |
9f9baab3 | 625 | * |
1da177e4 LT |
626 | * Fix the length according to mod and prod if given. |
627 | */ | |
e26f0501 | 628 | end = XFS_AGBLOCK_MIN(tend, args->agbno + args->maxlen); |
1da177e4 LT |
629 | args->len = end - args->agbno; |
630 | xfs_alloc_fix_len(args); | |
9f9baab3 CH |
631 | if (!xfs_alloc_fix_minleft(args)) |
632 | goto not_found; | |
633 | ||
1da177e4 | 634 | rlen = args->len; |
e26f0501 | 635 | ASSERT(args->agbno + rlen <= tend); |
1da177e4 | 636 | end = args->agbno + rlen; |
9f9baab3 | 637 | |
1da177e4 LT |
638 | /* |
639 | * We are allocating agbno for rlen [agbno .. end] | |
640 | * Allocate/initialize a cursor for the by-size btree. | |
641 | */ | |
561f7d17 CH |
642 | cnt_cur = xfs_allocbt_init_cursor(args->mp, args->tp, args->agbp, |
643 | args->agno, XFS_BTNUM_CNT); | |
1da177e4 | 644 | ASSERT(args->agbno + args->len <= |
16259e7d | 645 | be32_to_cpu(XFS_BUF_TO_AGF(args->agbp)->agf_length)); |
9f9baab3 CH |
646 | error = xfs_alloc_fixup_trees(cnt_cur, bno_cur, fbno, flen, args->agbno, |
647 | args->len, XFSA_FIXUP_BNO_OK); | |
648 | if (error) { | |
1da177e4 LT |
649 | xfs_btree_del_cursor(cnt_cur, XFS_BTREE_ERROR); |
650 | goto error0; | |
651 | } | |
9f9baab3 | 652 | |
1da177e4 LT |
653 | xfs_btree_del_cursor(bno_cur, XFS_BTREE_NOERROR); |
654 | xfs_btree_del_cursor(cnt_cur, XFS_BTREE_NOERROR); | |
0b1b213f | 655 | |
1da177e4 | 656 | args->wasfromfl = 0; |
9f9baab3 CH |
657 | trace_xfs_alloc_exact_done(args); |
658 | return 0; | |
659 | ||
660 | not_found: | |
661 | /* Didn't find it, return null. */ | |
662 | xfs_btree_del_cursor(bno_cur, XFS_BTREE_NOERROR); | |
663 | args->agbno = NULLAGBLOCK; | |
664 | trace_xfs_alloc_exact_notfound(args); | |
1da177e4 LT |
665 | return 0; |
666 | ||
667 | error0: | |
668 | xfs_btree_del_cursor(bno_cur, XFS_BTREE_ERROR); | |
0b1b213f | 669 | trace_xfs_alloc_exact_error(args); |
1da177e4 LT |
670 | return error; |
671 | } | |
672 | ||
489a150f CH |
673 | /* |
674 | * Search the btree in a given direction via the search cursor and compare | |
675 | * the records found against the good extent we've already found. | |
676 | */ | |
677 | STATIC int | |
678 | xfs_alloc_find_best_extent( | |
679 | struct xfs_alloc_arg *args, /* allocation argument structure */ | |
680 | struct xfs_btree_cur **gcur, /* good cursor */ | |
681 | struct xfs_btree_cur **scur, /* searching cursor */ | |
682 | xfs_agblock_t gdiff, /* difference for search comparison */ | |
683 | xfs_agblock_t *sbno, /* extent found by search */ | |
e26f0501 CH |
684 | xfs_extlen_t *slen, /* extent length */ |
685 | xfs_agblock_t *sbnoa, /* aligned extent found by search */ | |
686 | xfs_extlen_t *slena, /* aligned extent length */ | |
489a150f CH |
687 | int dir) /* 0 = search right, 1 = search left */ |
688 | { | |
489a150f CH |
689 | xfs_agblock_t new; |
690 | xfs_agblock_t sdiff; | |
691 | int error; | |
692 | int i; | |
693 | ||
694 | /* The good extent is perfect, no need to search. */ | |
695 | if (!gdiff) | |
696 | goto out_use_good; | |
697 | ||
698 | /* | |
699 | * Look until we find a better one, run out of space or run off the end. | |
700 | */ | |
701 | do { | |
702 | error = xfs_alloc_get_rec(*scur, sbno, slen, &i); | |
703 | if (error) | |
704 | goto error0; | |
705 | XFS_WANT_CORRUPTED_GOTO(i == 1, error0); | |
e26f0501 | 706 | xfs_alloc_compute_aligned(args, *sbno, *slen, sbnoa, slena); |
489a150f CH |
707 | |
708 | /* | |
709 | * The good extent is closer than this one. | |
710 | */ | |
711 | if (!dir) { | |
e26f0501 | 712 | if (*sbnoa >= args->agbno + gdiff) |
489a150f CH |
713 | goto out_use_good; |
714 | } else { | |
e26f0501 | 715 | if (*sbnoa <= args->agbno - gdiff) |
489a150f CH |
716 | goto out_use_good; |
717 | } | |
718 | ||
719 | /* | |
720 | * Same distance, compare length and pick the best. | |
721 | */ | |
722 | if (*slena >= args->minlen) { | |
723 | args->len = XFS_EXTLEN_MIN(*slena, args->maxlen); | |
724 | xfs_alloc_fix_len(args); | |
725 | ||
726 | sdiff = xfs_alloc_compute_diff(args->agbno, args->len, | |
e26f0501 CH |
727 | args->alignment, *sbnoa, |
728 | *slena, &new); | |
489a150f CH |
729 | |
730 | /* | |
731 | * Choose closer size and invalidate other cursor. | |
732 | */ | |
733 | if (sdiff < gdiff) | |
734 | goto out_use_search; | |
735 | goto out_use_good; | |
736 | } | |
737 | ||
738 | if (!dir) | |
739 | error = xfs_btree_increment(*scur, 0, &i); | |
740 | else | |
741 | error = xfs_btree_decrement(*scur, 0, &i); | |
742 | if (error) | |
743 | goto error0; | |
744 | } while (i); | |
745 | ||
746 | out_use_good: | |
747 | xfs_btree_del_cursor(*scur, XFS_BTREE_NOERROR); | |
748 | *scur = NULL; | |
749 | return 0; | |
750 | ||
751 | out_use_search: | |
752 | xfs_btree_del_cursor(*gcur, XFS_BTREE_NOERROR); | |
753 | *gcur = NULL; | |
754 | return 0; | |
755 | ||
756 | error0: | |
757 | /* caller invalidates cursors */ | |
758 | return error; | |
759 | } | |
760 | ||
1da177e4 LT |
761 | /* |
762 | * Allocate a variable extent near bno in the allocation group agno. | |
763 | * Extent's length (returned in len) will be between minlen and maxlen, | |
764 | * and of the form k * prod + mod unless there's nothing that large. | |
765 | * Return the starting a.g. block, or NULLAGBLOCK if we can't do it. | |
766 | */ | |
767 | STATIC int /* error */ | |
768 | xfs_alloc_ag_vextent_near( | |
769 | xfs_alloc_arg_t *args) /* allocation argument structure */ | |
770 | { | |
771 | xfs_btree_cur_t *bno_cur_gt; /* cursor for bno btree, right side */ | |
772 | xfs_btree_cur_t *bno_cur_lt; /* cursor for bno btree, left side */ | |
773 | xfs_btree_cur_t *cnt_cur; /* cursor for count btree */ | |
1da177e4 LT |
774 | xfs_agblock_t gtbno; /* start bno of right side entry */ |
775 | xfs_agblock_t gtbnoa; /* aligned ... */ | |
776 | xfs_extlen_t gtdiff; /* difference to right side entry */ | |
777 | xfs_extlen_t gtlen; /* length of right side entry */ | |
e26f0501 | 778 | xfs_extlen_t gtlena; /* aligned ... */ |
1da177e4 LT |
779 | xfs_agblock_t gtnew; /* useful start bno of right side */ |
780 | int error; /* error code */ | |
781 | int i; /* result code, temporary */ | |
782 | int j; /* result code, temporary */ | |
783 | xfs_agblock_t ltbno; /* start bno of left side entry */ | |
784 | xfs_agblock_t ltbnoa; /* aligned ... */ | |
785 | xfs_extlen_t ltdiff; /* difference to left side entry */ | |
1da177e4 | 786 | xfs_extlen_t ltlen; /* length of left side entry */ |
e26f0501 | 787 | xfs_extlen_t ltlena; /* aligned ... */ |
1da177e4 LT |
788 | xfs_agblock_t ltnew; /* useful start bno of left side */ |
789 | xfs_extlen_t rlen; /* length of returned extent */ | |
e26f0501 | 790 | int forced = 0; |
1da177e4 LT |
791 | #if defined(DEBUG) && defined(__KERNEL__) |
792 | /* | |
793 | * Randomly don't execute the first algorithm. | |
794 | */ | |
795 | int dofirst; /* set to do first algorithm */ | |
796 | ||
e7a23a9b | 797 | dofirst = random32() & 1; |
1da177e4 | 798 | #endif |
e26f0501 CH |
799 | |
800 | restart: | |
801 | bno_cur_lt = NULL; | |
802 | bno_cur_gt = NULL; | |
803 | ltlen = 0; | |
804 | gtlena = 0; | |
805 | ltlena = 0; | |
806 | ||
1da177e4 LT |
807 | /* |
808 | * Get a cursor for the by-size btree. | |
809 | */ | |
561f7d17 CH |
810 | cnt_cur = xfs_allocbt_init_cursor(args->mp, args->tp, args->agbp, |
811 | args->agno, XFS_BTNUM_CNT); | |
e26f0501 | 812 | |
1da177e4 LT |
813 | /* |
814 | * See if there are any free extents as big as maxlen. | |
815 | */ | |
816 | if ((error = xfs_alloc_lookup_ge(cnt_cur, 0, args->maxlen, &i))) | |
817 | goto error0; | |
818 | /* | |
819 | * If none, then pick up the last entry in the tree unless the | |
820 | * tree is empty. | |
821 | */ | |
822 | if (!i) { | |
823 | if ((error = xfs_alloc_ag_vextent_small(args, cnt_cur, <bno, | |
824 | <len, &i))) | |
825 | goto error0; | |
826 | if (i == 0 || ltlen == 0) { | |
827 | xfs_btree_del_cursor(cnt_cur, XFS_BTREE_NOERROR); | |
e26f0501 | 828 | trace_xfs_alloc_near_noentry(args); |
1da177e4 LT |
829 | return 0; |
830 | } | |
831 | ASSERT(i == 1); | |
832 | } | |
833 | args->wasfromfl = 0; | |
e26f0501 | 834 | |
1da177e4 LT |
835 | /* |
836 | * First algorithm. | |
837 | * If the requested extent is large wrt the freespaces available | |
838 | * in this a.g., then the cursor will be pointing to a btree entry | |
839 | * near the right edge of the tree. If it's in the last btree leaf | |
840 | * block, then we just examine all the entries in that block | |
841 | * that are big enough, and pick the best one. | |
842 | * This is written as a while loop so we can break out of it, | |
843 | * but we never loop back to the top. | |
844 | */ | |
845 | while (xfs_btree_islastblock(cnt_cur, 0)) { | |
846 | xfs_extlen_t bdiff; | |
847 | int besti=0; | |
848 | xfs_extlen_t blen=0; | |
849 | xfs_agblock_t bnew=0; | |
850 | ||
851 | #if defined(DEBUG) && defined(__KERNEL__) | |
852 | if (!dofirst) | |
853 | break; | |
854 | #endif | |
855 | /* | |
856 | * Start from the entry that lookup found, sequence through | |
857 | * all larger free blocks. If we're actually pointing at a | |
858 | * record smaller than maxlen, go to the start of this block, | |
859 | * and skip all those smaller than minlen. | |
860 | */ | |
861 | if (ltlen || args->alignment > 1) { | |
862 | cnt_cur->bc_ptrs[0] = 1; | |
863 | do { | |
864 | if ((error = xfs_alloc_get_rec(cnt_cur, <bno, | |
865 | <len, &i))) | |
866 | goto error0; | |
867 | XFS_WANT_CORRUPTED_GOTO(i == 1, error0); | |
868 | if (ltlen >= args->minlen) | |
869 | break; | |
637aa50f | 870 | if ((error = xfs_btree_increment(cnt_cur, 0, &i))) |
1da177e4 LT |
871 | goto error0; |
872 | } while (i); | |
873 | ASSERT(ltlen >= args->minlen); | |
874 | if (!i) | |
875 | break; | |
876 | } | |
877 | i = cnt_cur->bc_ptrs[0]; | |
878 | for (j = 1, blen = 0, bdiff = 0; | |
879 | !error && j && (blen < args->maxlen || bdiff > 0); | |
637aa50f | 880 | error = xfs_btree_increment(cnt_cur, 0, &j)) { |
1da177e4 LT |
881 | /* |
882 | * For each entry, decide if it's better than | |
883 | * the previous best entry. | |
884 | */ | |
885 | if ((error = xfs_alloc_get_rec(cnt_cur, <bno, <len, &i))) | |
886 | goto error0; | |
887 | XFS_WANT_CORRUPTED_GOTO(i == 1, error0); | |
86fa8af6 CH |
888 | xfs_alloc_compute_aligned(args, ltbno, ltlen, |
889 | <bnoa, <lena); | |
e6430037 | 890 | if (ltlena < args->minlen) |
1da177e4 LT |
891 | continue; |
892 | args->len = XFS_EXTLEN_MIN(ltlena, args->maxlen); | |
893 | xfs_alloc_fix_len(args); | |
894 | ASSERT(args->len >= args->minlen); | |
895 | if (args->len < blen) | |
896 | continue; | |
897 | ltdiff = xfs_alloc_compute_diff(args->agbno, args->len, | |
e26f0501 | 898 | args->alignment, ltbnoa, ltlena, <new); |
1da177e4 LT |
899 | if (ltnew != NULLAGBLOCK && |
900 | (args->len > blen || ltdiff < bdiff)) { | |
901 | bdiff = ltdiff; | |
902 | bnew = ltnew; | |
903 | blen = args->len; | |
904 | besti = cnt_cur->bc_ptrs[0]; | |
905 | } | |
906 | } | |
907 | /* | |
908 | * It didn't work. We COULD be in a case where | |
909 | * there's a good record somewhere, so try again. | |
910 | */ | |
911 | if (blen == 0) | |
912 | break; | |
913 | /* | |
914 | * Point at the best entry, and retrieve it again. | |
915 | */ | |
916 | cnt_cur->bc_ptrs[0] = besti; | |
917 | if ((error = xfs_alloc_get_rec(cnt_cur, <bno, <len, &i))) | |
918 | goto error0; | |
919 | XFS_WANT_CORRUPTED_GOTO(i == 1, error0); | |
73523a2e | 920 | ASSERT(ltbno + ltlen <= be32_to_cpu(XFS_BUF_TO_AGF(args->agbp)->agf_length)); |
1da177e4 LT |
921 | args->len = blen; |
922 | if (!xfs_alloc_fix_minleft(args)) { | |
923 | xfs_btree_del_cursor(cnt_cur, XFS_BTREE_NOERROR); | |
0b1b213f | 924 | trace_xfs_alloc_near_nominleft(args); |
1da177e4 LT |
925 | return 0; |
926 | } | |
927 | blen = args->len; | |
928 | /* | |
929 | * We are allocating starting at bnew for blen blocks. | |
930 | */ | |
931 | args->agbno = bnew; | |
932 | ASSERT(bnew >= ltbno); | |
73523a2e | 933 | ASSERT(bnew + blen <= ltbno + ltlen); |
1da177e4 LT |
934 | /* |
935 | * Set up a cursor for the by-bno tree. | |
936 | */ | |
561f7d17 CH |
937 | bno_cur_lt = xfs_allocbt_init_cursor(args->mp, args->tp, |
938 | args->agbp, args->agno, XFS_BTNUM_BNO); | |
1da177e4 LT |
939 | /* |
940 | * Fix up the btree entries. | |
941 | */ | |
942 | if ((error = xfs_alloc_fixup_trees(cnt_cur, bno_cur_lt, ltbno, | |
943 | ltlen, bnew, blen, XFSA_FIXUP_CNT_OK))) | |
944 | goto error0; | |
945 | xfs_btree_del_cursor(cnt_cur, XFS_BTREE_NOERROR); | |
946 | xfs_btree_del_cursor(bno_cur_lt, XFS_BTREE_NOERROR); | |
0b1b213f CH |
947 | |
948 | trace_xfs_alloc_near_first(args); | |
1da177e4 LT |
949 | return 0; |
950 | } | |
951 | /* | |
952 | * Second algorithm. | |
953 | * Search in the by-bno tree to the left and to the right | |
954 | * simultaneously, until in each case we find a space big enough, | |
955 | * or run into the edge of the tree. When we run into the edge, | |
956 | * we deallocate that cursor. | |
957 | * If both searches succeed, we compare the two spaces and pick | |
958 | * the better one. | |
959 | * With alignment, it's possible for both to fail; the upper | |
960 | * level algorithm that picks allocation groups for allocations | |
961 | * is not supposed to do this. | |
962 | */ | |
963 | /* | |
964 | * Allocate and initialize the cursor for the leftward search. | |
965 | */ | |
561f7d17 CH |
966 | bno_cur_lt = xfs_allocbt_init_cursor(args->mp, args->tp, args->agbp, |
967 | args->agno, XFS_BTNUM_BNO); | |
1da177e4 LT |
968 | /* |
969 | * Lookup <= bno to find the leftward search's starting point. | |
970 | */ | |
971 | if ((error = xfs_alloc_lookup_le(bno_cur_lt, args->agbno, args->maxlen, &i))) | |
972 | goto error0; | |
973 | if (!i) { | |
974 | /* | |
975 | * Didn't find anything; use this cursor for the rightward | |
976 | * search. | |
977 | */ | |
978 | bno_cur_gt = bno_cur_lt; | |
979 | bno_cur_lt = NULL; | |
980 | } | |
981 | /* | |
982 | * Found something. Duplicate the cursor for the rightward search. | |
983 | */ | |
984 | else if ((error = xfs_btree_dup_cursor(bno_cur_lt, &bno_cur_gt))) | |
985 | goto error0; | |
986 | /* | |
987 | * Increment the cursor, so we will point at the entry just right | |
988 | * of the leftward entry if any, or to the leftmost entry. | |
989 | */ | |
637aa50f | 990 | if ((error = xfs_btree_increment(bno_cur_gt, 0, &i))) |
1da177e4 LT |
991 | goto error0; |
992 | if (!i) { | |
993 | /* | |
994 | * It failed, there are no rightward entries. | |
995 | */ | |
996 | xfs_btree_del_cursor(bno_cur_gt, XFS_BTREE_NOERROR); | |
997 | bno_cur_gt = NULL; | |
998 | } | |
999 | /* | |
1000 | * Loop going left with the leftward cursor, right with the | |
1001 | * rightward cursor, until either both directions give up or | |
1002 | * we find an entry at least as big as minlen. | |
1003 | */ | |
1004 | do { | |
1005 | if (bno_cur_lt) { | |
1006 | if ((error = xfs_alloc_get_rec(bno_cur_lt, <bno, <len, &i))) | |
1007 | goto error0; | |
1008 | XFS_WANT_CORRUPTED_GOTO(i == 1, error0); | |
86fa8af6 CH |
1009 | xfs_alloc_compute_aligned(args, ltbno, ltlen, |
1010 | <bnoa, <lena); | |
12375c82 | 1011 | if (ltlena >= args->minlen) |
1da177e4 | 1012 | break; |
8df4da4a | 1013 | if ((error = xfs_btree_decrement(bno_cur_lt, 0, &i))) |
1da177e4 LT |
1014 | goto error0; |
1015 | if (!i) { | |
1016 | xfs_btree_del_cursor(bno_cur_lt, | |
1017 | XFS_BTREE_NOERROR); | |
1018 | bno_cur_lt = NULL; | |
1019 | } | |
1020 | } | |
1021 | if (bno_cur_gt) { | |
1022 | if ((error = xfs_alloc_get_rec(bno_cur_gt, >bno, >len, &i))) | |
1023 | goto error0; | |
1024 | XFS_WANT_CORRUPTED_GOTO(i == 1, error0); | |
86fa8af6 CH |
1025 | xfs_alloc_compute_aligned(args, gtbno, gtlen, |
1026 | >bnoa, >lena); | |
12375c82 | 1027 | if (gtlena >= args->minlen) |
1da177e4 | 1028 | break; |
637aa50f | 1029 | if ((error = xfs_btree_increment(bno_cur_gt, 0, &i))) |
1da177e4 LT |
1030 | goto error0; |
1031 | if (!i) { | |
1032 | xfs_btree_del_cursor(bno_cur_gt, | |
1033 | XFS_BTREE_NOERROR); | |
1034 | bno_cur_gt = NULL; | |
1035 | } | |
1036 | } | |
1037 | } while (bno_cur_lt || bno_cur_gt); | |
489a150f | 1038 | |
1da177e4 LT |
1039 | /* |
1040 | * Got both cursors still active, need to find better entry. | |
1041 | */ | |
1042 | if (bno_cur_lt && bno_cur_gt) { | |
1da177e4 LT |
1043 | if (ltlena >= args->minlen) { |
1044 | /* | |
489a150f | 1045 | * Left side is good, look for a right side entry. |
1da177e4 LT |
1046 | */ |
1047 | args->len = XFS_EXTLEN_MIN(ltlena, args->maxlen); | |
1048 | xfs_alloc_fix_len(args); | |
489a150f | 1049 | ltdiff = xfs_alloc_compute_diff(args->agbno, args->len, |
e26f0501 | 1050 | args->alignment, ltbnoa, ltlena, <new); |
489a150f CH |
1051 | |
1052 | error = xfs_alloc_find_best_extent(args, | |
1053 | &bno_cur_lt, &bno_cur_gt, | |
e26f0501 CH |
1054 | ltdiff, >bno, >len, |
1055 | >bnoa, >lena, | |
489a150f CH |
1056 | 0 /* search right */); |
1057 | } else { | |
1058 | ASSERT(gtlena >= args->minlen); | |
1059 | ||
1da177e4 | 1060 | /* |
489a150f | 1061 | * Right side is good, look for a left side entry. |
1da177e4 LT |
1062 | */ |
1063 | args->len = XFS_EXTLEN_MIN(gtlena, args->maxlen); | |
1064 | xfs_alloc_fix_len(args); | |
489a150f | 1065 | gtdiff = xfs_alloc_compute_diff(args->agbno, args->len, |
e26f0501 | 1066 | args->alignment, gtbnoa, gtlena, >new); |
489a150f CH |
1067 | |
1068 | error = xfs_alloc_find_best_extent(args, | |
1069 | &bno_cur_gt, &bno_cur_lt, | |
e26f0501 CH |
1070 | gtdiff, <bno, <len, |
1071 | <bnoa, <lena, | |
489a150f | 1072 | 1 /* search left */); |
1da177e4 | 1073 | } |
489a150f CH |
1074 | |
1075 | if (error) | |
1076 | goto error0; | |
1da177e4 | 1077 | } |
489a150f | 1078 | |
1da177e4 LT |
1079 | /* |
1080 | * If we couldn't get anything, give up. | |
1081 | */ | |
1082 | if (bno_cur_lt == NULL && bno_cur_gt == NULL) { | |
e26f0501 CH |
1083 | if (!forced++) { |
1084 | trace_xfs_alloc_near_busy(args); | |
1085 | xfs_log_force(args->mp, XFS_LOG_SYNC); | |
1086 | goto restart; | |
1087 | } | |
1088 | ||
0b1b213f | 1089 | trace_xfs_alloc_size_neither(args); |
1da177e4 LT |
1090 | args->agbno = NULLAGBLOCK; |
1091 | return 0; | |
1092 | } | |
489a150f | 1093 | |
1da177e4 LT |
1094 | /* |
1095 | * At this point we have selected a freespace entry, either to the | |
1096 | * left or to the right. If it's on the right, copy all the | |
1097 | * useful variables to the "left" set so we only have one | |
1098 | * copy of this code. | |
1099 | */ | |
1100 | if (bno_cur_gt) { | |
1101 | bno_cur_lt = bno_cur_gt; | |
1102 | bno_cur_gt = NULL; | |
1103 | ltbno = gtbno; | |
1104 | ltbnoa = gtbnoa; | |
1105 | ltlen = gtlen; | |
1106 | ltlena = gtlena; | |
1107 | j = 1; | |
1108 | } else | |
1109 | j = 0; | |
489a150f | 1110 | |
1da177e4 LT |
1111 | /* |
1112 | * Fix up the length and compute the useful address. | |
1113 | */ | |
1da177e4 LT |
1114 | args->len = XFS_EXTLEN_MIN(ltlena, args->maxlen); |
1115 | xfs_alloc_fix_len(args); | |
1116 | if (!xfs_alloc_fix_minleft(args)) { | |
0b1b213f | 1117 | trace_xfs_alloc_near_nominleft(args); |
1da177e4 LT |
1118 | xfs_btree_del_cursor(bno_cur_lt, XFS_BTREE_NOERROR); |
1119 | xfs_btree_del_cursor(cnt_cur, XFS_BTREE_NOERROR); | |
1120 | return 0; | |
1121 | } | |
1122 | rlen = args->len; | |
e26f0501 CH |
1123 | (void)xfs_alloc_compute_diff(args->agbno, rlen, args->alignment, |
1124 | ltbnoa, ltlena, <new); | |
1da177e4 | 1125 | ASSERT(ltnew >= ltbno); |
e26f0501 | 1126 | ASSERT(ltnew + rlen <= ltbnoa + ltlena); |
16259e7d | 1127 | ASSERT(ltnew + rlen <= be32_to_cpu(XFS_BUF_TO_AGF(args->agbp)->agf_length)); |
1da177e4 | 1128 | args->agbno = ltnew; |
e26f0501 | 1129 | |
1da177e4 LT |
1130 | if ((error = xfs_alloc_fixup_trees(cnt_cur, bno_cur_lt, ltbno, ltlen, |
1131 | ltnew, rlen, XFSA_FIXUP_BNO_OK))) | |
1132 | goto error0; | |
0b1b213f CH |
1133 | |
1134 | if (j) | |
1135 | trace_xfs_alloc_near_greater(args); | |
1136 | else | |
1137 | trace_xfs_alloc_near_lesser(args); | |
1138 | ||
1da177e4 LT |
1139 | xfs_btree_del_cursor(cnt_cur, XFS_BTREE_NOERROR); |
1140 | xfs_btree_del_cursor(bno_cur_lt, XFS_BTREE_NOERROR); | |
1141 | return 0; | |
1142 | ||
1143 | error0: | |
0b1b213f | 1144 | trace_xfs_alloc_near_error(args); |
1da177e4 LT |
1145 | if (cnt_cur != NULL) |
1146 | xfs_btree_del_cursor(cnt_cur, XFS_BTREE_ERROR); | |
1147 | if (bno_cur_lt != NULL) | |
1148 | xfs_btree_del_cursor(bno_cur_lt, XFS_BTREE_ERROR); | |
1149 | if (bno_cur_gt != NULL) | |
1150 | xfs_btree_del_cursor(bno_cur_gt, XFS_BTREE_ERROR); | |
1151 | return error; | |
1152 | } | |
1153 | ||
1154 | /* | |
1155 | * Allocate a variable extent anywhere in the allocation group agno. | |
1156 | * Extent's length (returned in len) will be between minlen and maxlen, | |
1157 | * and of the form k * prod + mod unless there's nothing that large. | |
1158 | * Return the starting a.g. block, or NULLAGBLOCK if we can't do it. | |
1159 | */ | |
1160 | STATIC int /* error */ | |
1161 | xfs_alloc_ag_vextent_size( | |
1162 | xfs_alloc_arg_t *args) /* allocation argument structure */ | |
1163 | { | |
1164 | xfs_btree_cur_t *bno_cur; /* cursor for bno btree */ | |
1165 | xfs_btree_cur_t *cnt_cur; /* cursor for cnt btree */ | |
1166 | int error; /* error result */ | |
1167 | xfs_agblock_t fbno; /* start of found freespace */ | |
1168 | xfs_extlen_t flen; /* length of found freespace */ | |
1da177e4 LT |
1169 | int i; /* temp status variable */ |
1170 | xfs_agblock_t rbno; /* returned block number */ | |
1171 | xfs_extlen_t rlen; /* length of returned extent */ | |
e26f0501 | 1172 | int forced = 0; |
1da177e4 | 1173 | |
e26f0501 | 1174 | restart: |
1da177e4 LT |
1175 | /* |
1176 | * Allocate and initialize a cursor for the by-size btree. | |
1177 | */ | |
561f7d17 CH |
1178 | cnt_cur = xfs_allocbt_init_cursor(args->mp, args->tp, args->agbp, |
1179 | args->agno, XFS_BTNUM_CNT); | |
1da177e4 | 1180 | bno_cur = NULL; |
e26f0501 | 1181 | |
1da177e4 LT |
1182 | /* |
1183 | * Look for an entry >= maxlen+alignment-1 blocks. | |
1184 | */ | |
1185 | if ((error = xfs_alloc_lookup_ge(cnt_cur, 0, | |
1186 | args->maxlen + args->alignment - 1, &i))) | |
1187 | goto error0; | |
e26f0501 | 1188 | |
1da177e4 | 1189 | /* |
e26f0501 CH |
1190 | * If none or we have busy extents that we cannot allocate from, then |
1191 | * we have to settle for a smaller extent. In the case that there are | |
1192 | * no large extents, this will return the last entry in the tree unless | |
1193 | * the tree is empty. In the case that there are only busy large | |
1194 | * extents, this will return the largest small extent unless there | |
1195 | * are no smaller extents available. | |
1da177e4 | 1196 | */ |
e26f0501 CH |
1197 | if (!i || forced > 1) { |
1198 | error = xfs_alloc_ag_vextent_small(args, cnt_cur, | |
1199 | &fbno, &flen, &i); | |
1200 | if (error) | |
1da177e4 LT |
1201 | goto error0; |
1202 | if (i == 0 || flen == 0) { | |
1203 | xfs_btree_del_cursor(cnt_cur, XFS_BTREE_NOERROR); | |
0b1b213f | 1204 | trace_xfs_alloc_size_noentry(args); |
1da177e4 LT |
1205 | return 0; |
1206 | } | |
1207 | ASSERT(i == 1); | |
e26f0501 CH |
1208 | xfs_alloc_compute_aligned(args, fbno, flen, &rbno, &rlen); |
1209 | } else { | |
1210 | /* | |
1211 | * Search for a non-busy extent that is large enough. | |
1212 | * If we are at low space, don't check, or if we fall of | |
1213 | * the end of the btree, turn off the busy check and | |
1214 | * restart. | |
1215 | */ | |
1216 | for (;;) { | |
1217 | error = xfs_alloc_get_rec(cnt_cur, &fbno, &flen, &i); | |
1218 | if (error) | |
1219 | goto error0; | |
1220 | XFS_WANT_CORRUPTED_GOTO(i == 1, error0); | |
1221 | ||
1222 | xfs_alloc_compute_aligned(args, fbno, flen, | |
1223 | &rbno, &rlen); | |
1224 | ||
1225 | if (rlen >= args->maxlen) | |
1226 | break; | |
1227 | ||
1228 | error = xfs_btree_increment(cnt_cur, 0, &i); | |
1229 | if (error) | |
1230 | goto error0; | |
1231 | if (i == 0) { | |
1232 | /* | |
1233 | * Our only valid extents must have been busy. | |
1234 | * Make it unbusy by forcing the log out and | |
1235 | * retrying. If we've been here before, forcing | |
1236 | * the log isn't making the extents available, | |
1237 | * which means they have probably been freed in | |
1238 | * this transaction. In that case, we have to | |
1239 | * give up on them and we'll attempt a minlen | |
1240 | * allocation the next time around. | |
1241 | */ | |
1242 | xfs_btree_del_cursor(cnt_cur, | |
1243 | XFS_BTREE_NOERROR); | |
1244 | trace_xfs_alloc_size_busy(args); | |
1245 | if (!forced++) | |
1246 | xfs_log_force(args->mp, XFS_LOG_SYNC); | |
1247 | goto restart; | |
1248 | } | |
1249 | } | |
1da177e4 | 1250 | } |
e26f0501 | 1251 | |
1da177e4 LT |
1252 | /* |
1253 | * In the first case above, we got the last entry in the | |
1254 | * by-size btree. Now we check to see if the space hits maxlen | |
1255 | * once aligned; if not, we search left for something better. | |
1256 | * This can't happen in the second case above. | |
1257 | */ | |
1da177e4 LT |
1258 | rlen = XFS_EXTLEN_MIN(args->maxlen, rlen); |
1259 | XFS_WANT_CORRUPTED_GOTO(rlen == 0 || | |
1260 | (rlen <= flen && rbno + rlen <= fbno + flen), error0); | |
1261 | if (rlen < args->maxlen) { | |
1262 | xfs_agblock_t bestfbno; | |
1263 | xfs_extlen_t bestflen; | |
1264 | xfs_agblock_t bestrbno; | |
1265 | xfs_extlen_t bestrlen; | |
1266 | ||
1267 | bestrlen = rlen; | |
1268 | bestrbno = rbno; | |
1269 | bestflen = flen; | |
1270 | bestfbno = fbno; | |
1271 | for (;;) { | |
8df4da4a | 1272 | if ((error = xfs_btree_decrement(cnt_cur, 0, &i))) |
1da177e4 LT |
1273 | goto error0; |
1274 | if (i == 0) | |
1275 | break; | |
1276 | if ((error = xfs_alloc_get_rec(cnt_cur, &fbno, &flen, | |
1277 | &i))) | |
1278 | goto error0; | |
1279 | XFS_WANT_CORRUPTED_GOTO(i == 1, error0); | |
1280 | if (flen < bestrlen) | |
1281 | break; | |
86fa8af6 CH |
1282 | xfs_alloc_compute_aligned(args, fbno, flen, |
1283 | &rbno, &rlen); | |
1da177e4 LT |
1284 | rlen = XFS_EXTLEN_MIN(args->maxlen, rlen); |
1285 | XFS_WANT_CORRUPTED_GOTO(rlen == 0 || | |
1286 | (rlen <= flen && rbno + rlen <= fbno + flen), | |
1287 | error0); | |
1288 | if (rlen > bestrlen) { | |
1289 | bestrlen = rlen; | |
1290 | bestrbno = rbno; | |
1291 | bestflen = flen; | |
1292 | bestfbno = fbno; | |
1293 | if (rlen == args->maxlen) | |
1294 | break; | |
1295 | } | |
1296 | } | |
1297 | if ((error = xfs_alloc_lookup_eq(cnt_cur, bestfbno, bestflen, | |
1298 | &i))) | |
1299 | goto error0; | |
1300 | XFS_WANT_CORRUPTED_GOTO(i == 1, error0); | |
1301 | rlen = bestrlen; | |
1302 | rbno = bestrbno; | |
1303 | flen = bestflen; | |
1304 | fbno = bestfbno; | |
1305 | } | |
1306 | args->wasfromfl = 0; | |
1307 | /* | |
1308 | * Fix up the length. | |
1309 | */ | |
1310 | args->len = rlen; | |
e26f0501 CH |
1311 | if (rlen < args->minlen) { |
1312 | if (!forced++) { | |
1313 | xfs_btree_del_cursor(cnt_cur, XFS_BTREE_NOERROR); | |
1314 | trace_xfs_alloc_size_busy(args); | |
1315 | xfs_log_force(args->mp, XFS_LOG_SYNC); | |
1316 | goto restart; | |
1317 | } | |
1318 | goto out_nominleft; | |
1da177e4 | 1319 | } |
e26f0501 CH |
1320 | xfs_alloc_fix_len(args); |
1321 | ||
1322 | if (!xfs_alloc_fix_minleft(args)) | |
1323 | goto out_nominleft; | |
1da177e4 LT |
1324 | rlen = args->len; |
1325 | XFS_WANT_CORRUPTED_GOTO(rlen <= flen, error0); | |
1326 | /* | |
1327 | * Allocate and initialize a cursor for the by-block tree. | |
1328 | */ | |
561f7d17 CH |
1329 | bno_cur = xfs_allocbt_init_cursor(args->mp, args->tp, args->agbp, |
1330 | args->agno, XFS_BTNUM_BNO); | |
1da177e4 LT |
1331 | if ((error = xfs_alloc_fixup_trees(cnt_cur, bno_cur, fbno, flen, |
1332 | rbno, rlen, XFSA_FIXUP_CNT_OK))) | |
1333 | goto error0; | |
1334 | xfs_btree_del_cursor(cnt_cur, XFS_BTREE_NOERROR); | |
1335 | xfs_btree_del_cursor(bno_cur, XFS_BTREE_NOERROR); | |
1336 | cnt_cur = bno_cur = NULL; | |
1337 | args->len = rlen; | |
1338 | args->agbno = rbno; | |
1339 | XFS_WANT_CORRUPTED_GOTO( | |
1340 | args->agbno + args->len <= | |
16259e7d | 1341 | be32_to_cpu(XFS_BUF_TO_AGF(args->agbp)->agf_length), |
1da177e4 | 1342 | error0); |
0b1b213f | 1343 | trace_xfs_alloc_size_done(args); |
1da177e4 LT |
1344 | return 0; |
1345 | ||
1346 | error0: | |
0b1b213f | 1347 | trace_xfs_alloc_size_error(args); |
1da177e4 LT |
1348 | if (cnt_cur) |
1349 | xfs_btree_del_cursor(cnt_cur, XFS_BTREE_ERROR); | |
1350 | if (bno_cur) | |
1351 | xfs_btree_del_cursor(bno_cur, XFS_BTREE_ERROR); | |
1352 | return error; | |
e26f0501 CH |
1353 | |
1354 | out_nominleft: | |
1355 | xfs_btree_del_cursor(cnt_cur, XFS_BTREE_NOERROR); | |
1356 | trace_xfs_alloc_size_nominleft(args); | |
1357 | args->agbno = NULLAGBLOCK; | |
1358 | return 0; | |
1da177e4 LT |
1359 | } |
1360 | ||
1361 | /* | |
1362 | * Deal with the case where only small freespaces remain. | |
1363 | * Either return the contents of the last freespace record, | |
1364 | * or allocate space from the freelist if there is nothing in the tree. | |
1365 | */ | |
1366 | STATIC int /* error */ | |
1367 | xfs_alloc_ag_vextent_small( | |
1368 | xfs_alloc_arg_t *args, /* allocation argument structure */ | |
1369 | xfs_btree_cur_t *ccur, /* by-size cursor */ | |
1370 | xfs_agblock_t *fbnop, /* result block number */ | |
1371 | xfs_extlen_t *flenp, /* result length */ | |
1372 | int *stat) /* status: 0-freelist, 1-normal/none */ | |
1373 | { | |
1374 | int error; | |
1375 | xfs_agblock_t fbno; | |
1376 | xfs_extlen_t flen; | |
1da177e4 LT |
1377 | int i; |
1378 | ||
8df4da4a | 1379 | if ((error = xfs_btree_decrement(ccur, 0, &i))) |
1da177e4 LT |
1380 | goto error0; |
1381 | if (i) { | |
1382 | if ((error = xfs_alloc_get_rec(ccur, &fbno, &flen, &i))) | |
1383 | goto error0; | |
1384 | XFS_WANT_CORRUPTED_GOTO(i == 1, error0); | |
1385 | } | |
1386 | /* | |
1387 | * Nothing in the btree, try the freelist. Make sure | |
1388 | * to respect minleft even when pulling from the | |
1389 | * freelist. | |
1390 | */ | |
1391 | else if (args->minlen == 1 && args->alignment == 1 && !args->isfl && | |
16259e7d CH |
1392 | (be32_to_cpu(XFS_BUF_TO_AGF(args->agbp)->agf_flcount) |
1393 | > args->minleft)) { | |
92821e2b DC |
1394 | error = xfs_alloc_get_freelist(args->tp, args->agbp, &fbno, 0); |
1395 | if (error) | |
1da177e4 LT |
1396 | goto error0; |
1397 | if (fbno != NULLAGBLOCK) { | |
97d3ac75 CH |
1398 | xfs_alloc_busy_reuse(args->mp, args->agno, fbno, 1, |
1399 | args->userdata); | |
1400 | ||
1da177e4 LT |
1401 | if (args->userdata) { |
1402 | xfs_buf_t *bp; | |
1403 | ||
1404 | bp = xfs_btree_get_bufs(args->mp, args->tp, | |
1405 | args->agno, fbno, 0); | |
1406 | xfs_trans_binval(args->tp, bp); | |
1407 | } | |
1408 | args->len = 1; | |
1409 | args->agbno = fbno; | |
1410 | XFS_WANT_CORRUPTED_GOTO( | |
1411 | args->agbno + args->len <= | |
16259e7d | 1412 | be32_to_cpu(XFS_BUF_TO_AGF(args->agbp)->agf_length), |
1da177e4 LT |
1413 | error0); |
1414 | args->wasfromfl = 1; | |
0b1b213f | 1415 | trace_xfs_alloc_small_freelist(args); |
1da177e4 LT |
1416 | *stat = 0; |
1417 | return 0; | |
1418 | } | |
1419 | /* | |
1420 | * Nothing in the freelist. | |
1421 | */ | |
1422 | else | |
1423 | flen = 0; | |
1424 | } | |
1425 | /* | |
1426 | * Can't allocate from the freelist for some reason. | |
1427 | */ | |
d432c80e NS |
1428 | else { |
1429 | fbno = NULLAGBLOCK; | |
1da177e4 | 1430 | flen = 0; |
d432c80e | 1431 | } |
1da177e4 LT |
1432 | /* |
1433 | * Can't do the allocation, give up. | |
1434 | */ | |
1435 | if (flen < args->minlen) { | |
1436 | args->agbno = NULLAGBLOCK; | |
0b1b213f | 1437 | trace_xfs_alloc_small_notenough(args); |
1da177e4 LT |
1438 | flen = 0; |
1439 | } | |
1440 | *fbnop = fbno; | |
1441 | *flenp = flen; | |
1442 | *stat = 1; | |
0b1b213f | 1443 | trace_xfs_alloc_small_done(args); |
1da177e4 LT |
1444 | return 0; |
1445 | ||
1446 | error0: | |
0b1b213f | 1447 | trace_xfs_alloc_small_error(args); |
1da177e4 LT |
1448 | return error; |
1449 | } | |
1450 | ||
1451 | /* | |
1452 | * Free the extent starting at agno/bno for length. | |
1453 | */ | |
1454 | STATIC int /* error */ | |
1455 | xfs_free_ag_extent( | |
1456 | xfs_trans_t *tp, /* transaction pointer */ | |
1457 | xfs_buf_t *agbp, /* buffer for a.g. freelist header */ | |
1458 | xfs_agnumber_t agno, /* allocation group number */ | |
1459 | xfs_agblock_t bno, /* starting block number */ | |
1460 | xfs_extlen_t len, /* length of extent */ | |
1461 | int isfl) /* set if is freelist blocks - no sb acctg */ | |
1462 | { | |
1463 | xfs_btree_cur_t *bno_cur; /* cursor for by-block btree */ | |
1464 | xfs_btree_cur_t *cnt_cur; /* cursor for by-size btree */ | |
1465 | int error; /* error return value */ | |
1da177e4 LT |
1466 | xfs_agblock_t gtbno; /* start of right neighbor block */ |
1467 | xfs_extlen_t gtlen; /* length of right neighbor block */ | |
1468 | int haveleft; /* have a left neighbor block */ | |
1469 | int haveright; /* have a right neighbor block */ | |
1470 | int i; /* temp, result code */ | |
1471 | xfs_agblock_t ltbno; /* start of left neighbor block */ | |
1472 | xfs_extlen_t ltlen; /* length of left neighbor block */ | |
1473 | xfs_mount_t *mp; /* mount point struct for filesystem */ | |
1474 | xfs_agblock_t nbno; /* new starting block of freespace */ | |
1475 | xfs_extlen_t nlen; /* new length of freespace */ | |
ecb6928f | 1476 | xfs_perag_t *pag; /* per allocation group data */ |
1da177e4 LT |
1477 | |
1478 | mp = tp->t_mountp; | |
1479 | /* | |
1480 | * Allocate and initialize a cursor for the by-block btree. | |
1481 | */ | |
561f7d17 | 1482 | bno_cur = xfs_allocbt_init_cursor(mp, tp, agbp, agno, XFS_BTNUM_BNO); |
1da177e4 LT |
1483 | cnt_cur = NULL; |
1484 | /* | |
1485 | * Look for a neighboring block on the left (lower block numbers) | |
1486 | * that is contiguous with this space. | |
1487 | */ | |
1488 | if ((error = xfs_alloc_lookup_le(bno_cur, bno, len, &haveleft))) | |
1489 | goto error0; | |
1490 | if (haveleft) { | |
1491 | /* | |
1492 | * There is a block to our left. | |
1493 | */ | |
1494 | if ((error = xfs_alloc_get_rec(bno_cur, <bno, <len, &i))) | |
1495 | goto error0; | |
1496 | XFS_WANT_CORRUPTED_GOTO(i == 1, error0); | |
1497 | /* | |
1498 | * It's not contiguous, though. | |
1499 | */ | |
1500 | if (ltbno + ltlen < bno) | |
1501 | haveleft = 0; | |
1502 | else { | |
1503 | /* | |
1504 | * If this failure happens the request to free this | |
1505 | * space was invalid, it's (partly) already free. | |
1506 | * Very bad. | |
1507 | */ | |
1508 | XFS_WANT_CORRUPTED_GOTO(ltbno + ltlen <= bno, error0); | |
1509 | } | |
1510 | } | |
1511 | /* | |
1512 | * Look for a neighboring block on the right (higher block numbers) | |
1513 | * that is contiguous with this space. | |
1514 | */ | |
637aa50f | 1515 | if ((error = xfs_btree_increment(bno_cur, 0, &haveright))) |
1da177e4 LT |
1516 | goto error0; |
1517 | if (haveright) { | |
1518 | /* | |
1519 | * There is a block to our right. | |
1520 | */ | |
1521 | if ((error = xfs_alloc_get_rec(bno_cur, >bno, >len, &i))) | |
1522 | goto error0; | |
1523 | XFS_WANT_CORRUPTED_GOTO(i == 1, error0); | |
1524 | /* | |
1525 | * It's not contiguous, though. | |
1526 | */ | |
1527 | if (bno + len < gtbno) | |
1528 | haveright = 0; | |
1529 | else { | |
1530 | /* | |
1531 | * If this failure happens the request to free this | |
1532 | * space was invalid, it's (partly) already free. | |
1533 | * Very bad. | |
1534 | */ | |
1535 | XFS_WANT_CORRUPTED_GOTO(gtbno >= bno + len, error0); | |
1536 | } | |
1537 | } | |
1538 | /* | |
1539 | * Now allocate and initialize a cursor for the by-size tree. | |
1540 | */ | |
561f7d17 | 1541 | cnt_cur = xfs_allocbt_init_cursor(mp, tp, agbp, agno, XFS_BTNUM_CNT); |
1da177e4 LT |
1542 | /* |
1543 | * Have both left and right contiguous neighbors. | |
1544 | * Merge all three into a single free block. | |
1545 | */ | |
1546 | if (haveleft && haveright) { | |
1547 | /* | |
1548 | * Delete the old by-size entry on the left. | |
1549 | */ | |
1550 | if ((error = xfs_alloc_lookup_eq(cnt_cur, ltbno, ltlen, &i))) | |
1551 | goto error0; | |
1552 | XFS_WANT_CORRUPTED_GOTO(i == 1, error0); | |
91cca5df | 1553 | if ((error = xfs_btree_delete(cnt_cur, &i))) |
1da177e4 LT |
1554 | goto error0; |
1555 | XFS_WANT_CORRUPTED_GOTO(i == 1, error0); | |
1556 | /* | |
1557 | * Delete the old by-size entry on the right. | |
1558 | */ | |
1559 | if ((error = xfs_alloc_lookup_eq(cnt_cur, gtbno, gtlen, &i))) | |
1560 | goto error0; | |
1561 | XFS_WANT_CORRUPTED_GOTO(i == 1, error0); | |
91cca5df | 1562 | if ((error = xfs_btree_delete(cnt_cur, &i))) |
1da177e4 LT |
1563 | goto error0; |
1564 | XFS_WANT_CORRUPTED_GOTO(i == 1, error0); | |
1565 | /* | |
1566 | * Delete the old by-block entry for the right block. | |
1567 | */ | |
91cca5df | 1568 | if ((error = xfs_btree_delete(bno_cur, &i))) |
1da177e4 LT |
1569 | goto error0; |
1570 | XFS_WANT_CORRUPTED_GOTO(i == 1, error0); | |
1571 | /* | |
1572 | * Move the by-block cursor back to the left neighbor. | |
1573 | */ | |
8df4da4a | 1574 | if ((error = xfs_btree_decrement(bno_cur, 0, &i))) |
1da177e4 LT |
1575 | goto error0; |
1576 | XFS_WANT_CORRUPTED_GOTO(i == 1, error0); | |
1577 | #ifdef DEBUG | |
1578 | /* | |
1579 | * Check that this is the right record: delete didn't | |
1580 | * mangle the cursor. | |
1581 | */ | |
1582 | { | |
1583 | xfs_agblock_t xxbno; | |
1584 | xfs_extlen_t xxlen; | |
1585 | ||
1586 | if ((error = xfs_alloc_get_rec(bno_cur, &xxbno, &xxlen, | |
1587 | &i))) | |
1588 | goto error0; | |
1589 | XFS_WANT_CORRUPTED_GOTO( | |
1590 | i == 1 && xxbno == ltbno && xxlen == ltlen, | |
1591 | error0); | |
1592 | } | |
1593 | #endif | |
1594 | /* | |
1595 | * Update remaining by-block entry to the new, joined block. | |
1596 | */ | |
1597 | nbno = ltbno; | |
1598 | nlen = len + ltlen + gtlen; | |
1599 | if ((error = xfs_alloc_update(bno_cur, nbno, nlen))) | |
1600 | goto error0; | |
1601 | } | |
1602 | /* | |
1603 | * Have only a left contiguous neighbor. | |
1604 | * Merge it together with the new freespace. | |
1605 | */ | |
1606 | else if (haveleft) { | |
1607 | /* | |
1608 | * Delete the old by-size entry on the left. | |
1609 | */ | |
1610 | if ((error = xfs_alloc_lookup_eq(cnt_cur, ltbno, ltlen, &i))) | |
1611 | goto error0; | |
1612 | XFS_WANT_CORRUPTED_GOTO(i == 1, error0); | |
91cca5df | 1613 | if ((error = xfs_btree_delete(cnt_cur, &i))) |
1da177e4 LT |
1614 | goto error0; |
1615 | XFS_WANT_CORRUPTED_GOTO(i == 1, error0); | |
1616 | /* | |
1617 | * Back up the by-block cursor to the left neighbor, and | |
1618 | * update its length. | |
1619 | */ | |
8df4da4a | 1620 | if ((error = xfs_btree_decrement(bno_cur, 0, &i))) |
1da177e4 LT |
1621 | goto error0; |
1622 | XFS_WANT_CORRUPTED_GOTO(i == 1, error0); | |
1623 | nbno = ltbno; | |
1624 | nlen = len + ltlen; | |
1625 | if ((error = xfs_alloc_update(bno_cur, nbno, nlen))) | |
1626 | goto error0; | |
1627 | } | |
1628 | /* | |
1629 | * Have only a right contiguous neighbor. | |
1630 | * Merge it together with the new freespace. | |
1631 | */ | |
1632 | else if (haveright) { | |
1633 | /* | |
1634 | * Delete the old by-size entry on the right. | |
1635 | */ | |
1636 | if ((error = xfs_alloc_lookup_eq(cnt_cur, gtbno, gtlen, &i))) | |
1637 | goto error0; | |
1638 | XFS_WANT_CORRUPTED_GOTO(i == 1, error0); | |
91cca5df | 1639 | if ((error = xfs_btree_delete(cnt_cur, &i))) |
1da177e4 LT |
1640 | goto error0; |
1641 | XFS_WANT_CORRUPTED_GOTO(i == 1, error0); | |
1642 | /* | |
1643 | * Update the starting block and length of the right | |
1644 | * neighbor in the by-block tree. | |
1645 | */ | |
1646 | nbno = bno; | |
1647 | nlen = len + gtlen; | |
1648 | if ((error = xfs_alloc_update(bno_cur, nbno, nlen))) | |
1649 | goto error0; | |
1650 | } | |
1651 | /* | |
1652 | * No contiguous neighbors. | |
1653 | * Insert the new freespace into the by-block tree. | |
1654 | */ | |
1655 | else { | |
1656 | nbno = bno; | |
1657 | nlen = len; | |
4b22a571 | 1658 | if ((error = xfs_btree_insert(bno_cur, &i))) |
1da177e4 LT |
1659 | goto error0; |
1660 | XFS_WANT_CORRUPTED_GOTO(i == 1, error0); | |
1661 | } | |
1662 | xfs_btree_del_cursor(bno_cur, XFS_BTREE_NOERROR); | |
1663 | bno_cur = NULL; | |
1664 | /* | |
1665 | * In all cases we need to insert the new freespace in the by-size tree. | |
1666 | */ | |
1667 | if ((error = xfs_alloc_lookup_eq(cnt_cur, nbno, nlen, &i))) | |
1668 | goto error0; | |
1669 | XFS_WANT_CORRUPTED_GOTO(i == 0, error0); | |
4b22a571 | 1670 | if ((error = xfs_btree_insert(cnt_cur, &i))) |
1da177e4 LT |
1671 | goto error0; |
1672 | XFS_WANT_CORRUPTED_GOTO(i == 1, error0); | |
1673 | xfs_btree_del_cursor(cnt_cur, XFS_BTREE_NOERROR); | |
1674 | cnt_cur = NULL; | |
ecb6928f | 1675 | |
1da177e4 LT |
1676 | /* |
1677 | * Update the freespace totals in the ag and superblock. | |
1678 | */ | |
ecb6928f CH |
1679 | pag = xfs_perag_get(mp, agno); |
1680 | error = xfs_alloc_update_counters(tp, pag, agbp, len); | |
1681 | xfs_perag_put(pag); | |
1682 | if (error) | |
1683 | goto error0; | |
1684 | ||
1685 | if (!isfl) | |
1686 | xfs_trans_mod_sb(tp, XFS_TRANS_SB_FDBLOCKS, (long)len); | |
1687 | XFS_STATS_INC(xs_freex); | |
1688 | XFS_STATS_ADD(xs_freeb, len); | |
0b1b213f CH |
1689 | |
1690 | trace_xfs_free_extent(mp, agno, bno, len, isfl, haveleft, haveright); | |
1da177e4 | 1691 | |
1da177e4 LT |
1692 | return 0; |
1693 | ||
1694 | error0: | |
0b1b213f | 1695 | trace_xfs_free_extent(mp, agno, bno, len, isfl, -1, -1); |
1da177e4 LT |
1696 | if (bno_cur) |
1697 | xfs_btree_del_cursor(bno_cur, XFS_BTREE_ERROR); | |
1698 | if (cnt_cur) | |
1699 | xfs_btree_del_cursor(cnt_cur, XFS_BTREE_ERROR); | |
1700 | return error; | |
1701 | } | |
1702 | ||
1703 | /* | |
1704 | * Visible (exported) allocation/free functions. | |
1705 | * Some of these are used just by xfs_alloc_btree.c and this file. | |
1706 | */ | |
1707 | ||
1708 | /* | |
1709 | * Compute and fill in value of m_ag_maxlevels. | |
1710 | */ | |
1711 | void | |
1712 | xfs_alloc_compute_maxlevels( | |
1713 | xfs_mount_t *mp) /* file system mount structure */ | |
1714 | { | |
1715 | int level; | |
1716 | uint maxblocks; | |
1717 | uint maxleafents; | |
1718 | int minleafrecs; | |
1719 | int minnoderecs; | |
1720 | ||
1721 | maxleafents = (mp->m_sb.sb_agblocks + 1) / 2; | |
1722 | minleafrecs = mp->m_alloc_mnr[0]; | |
1723 | minnoderecs = mp->m_alloc_mnr[1]; | |
1724 | maxblocks = (maxleafents + minleafrecs - 1) / minleafrecs; | |
1725 | for (level = 1; maxblocks > 1; level++) | |
1726 | maxblocks = (maxblocks + minnoderecs - 1) / minnoderecs; | |
1727 | mp->m_ag_maxlevels = level; | |
1728 | } | |
1729 | ||
6cc87645 DC |
1730 | /* |
1731 | * Find the length of the longest extent in an AG. | |
1732 | */ | |
1733 | xfs_extlen_t | |
1734 | xfs_alloc_longest_free_extent( | |
1735 | struct xfs_mount *mp, | |
1736 | struct xfs_perag *pag) | |
1737 | { | |
1738 | xfs_extlen_t need, delta = 0; | |
1739 | ||
1740 | need = XFS_MIN_FREELIST_PAG(pag, mp); | |
1741 | if (need > pag->pagf_flcount) | |
1742 | delta = need - pag->pagf_flcount; | |
1743 | ||
1744 | if (pag->pagf_longest > delta) | |
1745 | return pag->pagf_longest - delta; | |
1746 | return pag->pagf_flcount > 0 || pag->pagf_longest > 0; | |
1747 | } | |
1748 | ||
1da177e4 LT |
1749 | /* |
1750 | * Decide whether to use this allocation group for this allocation. | |
1751 | * If so, fix up the btree freelist's size. | |
1752 | */ | |
1753 | STATIC int /* error */ | |
1754 | xfs_alloc_fix_freelist( | |
1755 | xfs_alloc_arg_t *args, /* allocation argument structure */ | |
1756 | int flags) /* XFS_ALLOC_FLAG_... */ | |
1757 | { | |
1758 | xfs_buf_t *agbp; /* agf buffer pointer */ | |
1759 | xfs_agf_t *agf; /* a.g. freespace structure pointer */ | |
1760 | xfs_buf_t *agflbp;/* agfl buffer pointer */ | |
1761 | xfs_agblock_t bno; /* freelist block */ | |
1762 | xfs_extlen_t delta; /* new blocks needed in freelist */ | |
1763 | int error; /* error result code */ | |
1764 | xfs_extlen_t longest;/* longest extent in allocation group */ | |
1765 | xfs_mount_t *mp; /* file system mount point structure */ | |
1766 | xfs_extlen_t need; /* total blocks needed in freelist */ | |
1767 | xfs_perag_t *pag; /* per-ag information structure */ | |
1768 | xfs_alloc_arg_t targs; /* local allocation arguments */ | |
1769 | xfs_trans_t *tp; /* transaction pointer */ | |
1770 | ||
1771 | mp = args->mp; | |
1772 | ||
1773 | pag = args->pag; | |
1774 | tp = args->tp; | |
1775 | if (!pag->pagf_init) { | |
1776 | if ((error = xfs_alloc_read_agf(mp, tp, args->agno, flags, | |
1777 | &agbp))) | |
1778 | return error; | |
1779 | if (!pag->pagf_init) { | |
0e1edbd9 NS |
1780 | ASSERT(flags & XFS_ALLOC_FLAG_TRYLOCK); |
1781 | ASSERT(!(flags & XFS_ALLOC_FLAG_FREEING)); | |
1da177e4 LT |
1782 | args->agbp = NULL; |
1783 | return 0; | |
1784 | } | |
1785 | } else | |
1786 | agbp = NULL; | |
1787 | ||
0e1edbd9 NS |
1788 | /* |
1789 | * If this is a metadata preferred pag and we are user data | |
1da177e4 LT |
1790 | * then try somewhere else if we are not being asked to |
1791 | * try harder at this point | |
1792 | */ | |
0e1edbd9 NS |
1793 | if (pag->pagf_metadata && args->userdata && |
1794 | (flags & XFS_ALLOC_FLAG_TRYLOCK)) { | |
1795 | ASSERT(!(flags & XFS_ALLOC_FLAG_FREEING)); | |
1da177e4 LT |
1796 | args->agbp = NULL; |
1797 | return 0; | |
1798 | } | |
1799 | ||
0e1edbd9 | 1800 | if (!(flags & XFS_ALLOC_FLAG_FREEING)) { |
0e1edbd9 NS |
1801 | /* |
1802 | * If it looks like there isn't a long enough extent, or enough | |
1803 | * total blocks, reject it. | |
1804 | */ | |
6cc87645 DC |
1805 | need = XFS_MIN_FREELIST_PAG(pag, mp); |
1806 | longest = xfs_alloc_longest_free_extent(mp, pag); | |
0e1edbd9 NS |
1807 | if ((args->minlen + args->alignment + args->minalignslop - 1) > |
1808 | longest || | |
1809 | ((int)(pag->pagf_freeblks + pag->pagf_flcount - | |
1810 | need - args->total) < (int)args->minleft)) { | |
1811 | if (agbp) | |
1812 | xfs_trans_brelse(tp, agbp); | |
1813 | args->agbp = NULL; | |
1814 | return 0; | |
1815 | } | |
1da177e4 | 1816 | } |
0e1edbd9 | 1817 | |
1da177e4 LT |
1818 | /* |
1819 | * Get the a.g. freespace buffer. | |
1820 | * Can fail if we're not blocking on locks, and it's held. | |
1821 | */ | |
1822 | if (agbp == NULL) { | |
1823 | if ((error = xfs_alloc_read_agf(mp, tp, args->agno, flags, | |
1824 | &agbp))) | |
1825 | return error; | |
1826 | if (agbp == NULL) { | |
0e1edbd9 NS |
1827 | ASSERT(flags & XFS_ALLOC_FLAG_TRYLOCK); |
1828 | ASSERT(!(flags & XFS_ALLOC_FLAG_FREEING)); | |
1da177e4 LT |
1829 | args->agbp = NULL; |
1830 | return 0; | |
1831 | } | |
1832 | } | |
1833 | /* | |
1834 | * Figure out how many blocks we should have in the freelist. | |
1835 | */ | |
1836 | agf = XFS_BUF_TO_AGF(agbp); | |
1837 | need = XFS_MIN_FREELIST(agf, mp); | |
1da177e4 LT |
1838 | /* |
1839 | * If there isn't enough total or single-extent, reject it. | |
1840 | */ | |
0e1edbd9 NS |
1841 | if (!(flags & XFS_ALLOC_FLAG_FREEING)) { |
1842 | delta = need > be32_to_cpu(agf->agf_flcount) ? | |
1843 | (need - be32_to_cpu(agf->agf_flcount)) : 0; | |
1844 | longest = be32_to_cpu(agf->agf_longest); | |
1845 | longest = (longest > delta) ? (longest - delta) : | |
1846 | (be32_to_cpu(agf->agf_flcount) > 0 || longest > 0); | |
1847 | if ((args->minlen + args->alignment + args->minalignslop - 1) > | |
1848 | longest || | |
1849 | ((int)(be32_to_cpu(agf->agf_freeblks) + | |
1850 | be32_to_cpu(agf->agf_flcount) - need - args->total) < | |
1851 | (int)args->minleft)) { | |
1852 | xfs_trans_brelse(tp, agbp); | |
1853 | args->agbp = NULL; | |
1854 | return 0; | |
1855 | } | |
1da177e4 LT |
1856 | } |
1857 | /* | |
1858 | * Make the freelist shorter if it's too long. | |
1859 | */ | |
16259e7d | 1860 | while (be32_to_cpu(agf->agf_flcount) > need) { |
1da177e4 LT |
1861 | xfs_buf_t *bp; |
1862 | ||
92821e2b DC |
1863 | error = xfs_alloc_get_freelist(tp, agbp, &bno, 0); |
1864 | if (error) | |
1da177e4 LT |
1865 | return error; |
1866 | if ((error = xfs_free_ag_extent(tp, agbp, args->agno, bno, 1, 1))) | |
1867 | return error; | |
1868 | bp = xfs_btree_get_bufs(mp, tp, args->agno, bno, 0); | |
1869 | xfs_trans_binval(tp, bp); | |
1870 | } | |
1871 | /* | |
1872 | * Initialize the args structure. | |
1873 | */ | |
1874 | targs.tp = tp; | |
1875 | targs.mp = mp; | |
1876 | targs.agbp = agbp; | |
1877 | targs.agno = args->agno; | |
1878 | targs.mod = targs.minleft = targs.wasdel = targs.userdata = | |
1879 | targs.minalignslop = 0; | |
1880 | targs.alignment = targs.minlen = targs.prod = targs.isfl = 1; | |
1881 | targs.type = XFS_ALLOCTYPE_THIS_AG; | |
1882 | targs.pag = pag; | |
1883 | if ((error = xfs_alloc_read_agfl(mp, tp, targs.agno, &agflbp))) | |
1884 | return error; | |
1885 | /* | |
1886 | * Make the freelist longer if it's too short. | |
1887 | */ | |
16259e7d | 1888 | while (be32_to_cpu(agf->agf_flcount) < need) { |
1da177e4 | 1889 | targs.agbno = 0; |
16259e7d | 1890 | targs.maxlen = need - be32_to_cpu(agf->agf_flcount); |
1da177e4 LT |
1891 | /* |
1892 | * Allocate as many blocks as possible at once. | |
1893 | */ | |
e63a3690 NS |
1894 | if ((error = xfs_alloc_ag_vextent(&targs))) { |
1895 | xfs_trans_brelse(tp, agflbp); | |
1da177e4 | 1896 | return error; |
e63a3690 | 1897 | } |
1da177e4 LT |
1898 | /* |
1899 | * Stop if we run out. Won't happen if callers are obeying | |
1900 | * the restrictions correctly. Can happen for free calls | |
1901 | * on a completely full ag. | |
1902 | */ | |
d210a28c | 1903 | if (targs.agbno == NULLAGBLOCK) { |
0e1edbd9 NS |
1904 | if (flags & XFS_ALLOC_FLAG_FREEING) |
1905 | break; | |
1906 | xfs_trans_brelse(tp, agflbp); | |
1907 | args->agbp = NULL; | |
1908 | return 0; | |
d210a28c | 1909 | } |
1da177e4 LT |
1910 | /* |
1911 | * Put each allocated block on the list. | |
1912 | */ | |
1913 | for (bno = targs.agbno; bno < targs.agbno + targs.len; bno++) { | |
92821e2b DC |
1914 | error = xfs_alloc_put_freelist(tp, agbp, |
1915 | agflbp, bno, 0); | |
1916 | if (error) | |
1da177e4 LT |
1917 | return error; |
1918 | } | |
1919 | } | |
e63a3690 | 1920 | xfs_trans_brelse(tp, agflbp); |
1da177e4 LT |
1921 | args->agbp = agbp; |
1922 | return 0; | |
1923 | } | |
1924 | ||
1925 | /* | |
1926 | * Get a block from the freelist. | |
1927 | * Returns with the buffer for the block gotten. | |
1928 | */ | |
1929 | int /* error */ | |
1930 | xfs_alloc_get_freelist( | |
1931 | xfs_trans_t *tp, /* transaction pointer */ | |
1932 | xfs_buf_t *agbp, /* buffer containing the agf structure */ | |
92821e2b DC |
1933 | xfs_agblock_t *bnop, /* block address retrieved from freelist */ |
1934 | int btreeblk) /* destination is a AGF btree */ | |
1da177e4 LT |
1935 | { |
1936 | xfs_agf_t *agf; /* a.g. freespace structure */ | |
1937 | xfs_agfl_t *agfl; /* a.g. freelist structure */ | |
1938 | xfs_buf_t *agflbp;/* buffer for a.g. freelist structure */ | |
1939 | xfs_agblock_t bno; /* block number returned */ | |
1940 | int error; | |
92821e2b | 1941 | int logflags; |
1da177e4 LT |
1942 | xfs_mount_t *mp; /* mount structure */ |
1943 | xfs_perag_t *pag; /* per allocation group data */ | |
1944 | ||
1945 | agf = XFS_BUF_TO_AGF(agbp); | |
1946 | /* | |
1947 | * Freelist is empty, give up. | |
1948 | */ | |
1949 | if (!agf->agf_flcount) { | |
1950 | *bnop = NULLAGBLOCK; | |
1951 | return 0; | |
1952 | } | |
1953 | /* | |
1954 | * Read the array of free blocks. | |
1955 | */ | |
1956 | mp = tp->t_mountp; | |
1957 | if ((error = xfs_alloc_read_agfl(mp, tp, | |
16259e7d | 1958 | be32_to_cpu(agf->agf_seqno), &agflbp))) |
1da177e4 LT |
1959 | return error; |
1960 | agfl = XFS_BUF_TO_AGFL(agflbp); | |
1961 | /* | |
1962 | * Get the block number and update the data structures. | |
1963 | */ | |
e2101005 | 1964 | bno = be32_to_cpu(agfl->agfl_bno[be32_to_cpu(agf->agf_flfirst)]); |
413d57c9 | 1965 | be32_add_cpu(&agf->agf_flfirst, 1); |
1da177e4 | 1966 | xfs_trans_brelse(tp, agflbp); |
16259e7d | 1967 | if (be32_to_cpu(agf->agf_flfirst) == XFS_AGFL_SIZE(mp)) |
1da177e4 | 1968 | agf->agf_flfirst = 0; |
a862e0fd DC |
1969 | |
1970 | pag = xfs_perag_get(mp, be32_to_cpu(agf->agf_seqno)); | |
413d57c9 | 1971 | be32_add_cpu(&agf->agf_flcount, -1); |
1da177e4 LT |
1972 | xfs_trans_agflist_delta(tp, -1); |
1973 | pag->pagf_flcount--; | |
a862e0fd | 1974 | xfs_perag_put(pag); |
92821e2b DC |
1975 | |
1976 | logflags = XFS_AGF_FLFIRST | XFS_AGF_FLCOUNT; | |
1977 | if (btreeblk) { | |
413d57c9 | 1978 | be32_add_cpu(&agf->agf_btreeblks, 1); |
92821e2b DC |
1979 | pag->pagf_btreeblks++; |
1980 | logflags |= XFS_AGF_BTREEBLKS; | |
1981 | } | |
1982 | ||
92821e2b | 1983 | xfs_alloc_log_agf(tp, agbp, logflags); |
1da177e4 LT |
1984 | *bnop = bno; |
1985 | ||
1da177e4 LT |
1986 | return 0; |
1987 | } | |
1988 | ||
1989 | /* | |
1990 | * Log the given fields from the agf structure. | |
1991 | */ | |
1992 | void | |
1993 | xfs_alloc_log_agf( | |
1994 | xfs_trans_t *tp, /* transaction pointer */ | |
1995 | xfs_buf_t *bp, /* buffer for a.g. freelist header */ | |
1996 | int fields) /* mask of fields to be logged (XFS_AGF_...) */ | |
1997 | { | |
1998 | int first; /* first byte offset */ | |
1999 | int last; /* last byte offset */ | |
2000 | static const short offsets[] = { | |
2001 | offsetof(xfs_agf_t, agf_magicnum), | |
2002 | offsetof(xfs_agf_t, agf_versionnum), | |
2003 | offsetof(xfs_agf_t, agf_seqno), | |
2004 | offsetof(xfs_agf_t, agf_length), | |
2005 | offsetof(xfs_agf_t, agf_roots[0]), | |
2006 | offsetof(xfs_agf_t, agf_levels[0]), | |
2007 | offsetof(xfs_agf_t, agf_flfirst), | |
2008 | offsetof(xfs_agf_t, agf_fllast), | |
2009 | offsetof(xfs_agf_t, agf_flcount), | |
2010 | offsetof(xfs_agf_t, agf_freeblks), | |
2011 | offsetof(xfs_agf_t, agf_longest), | |
92821e2b | 2012 | offsetof(xfs_agf_t, agf_btreeblks), |
1da177e4 LT |
2013 | sizeof(xfs_agf_t) |
2014 | }; | |
2015 | ||
0b1b213f CH |
2016 | trace_xfs_agf(tp->t_mountp, XFS_BUF_TO_AGF(bp), fields, _RET_IP_); |
2017 | ||
1da177e4 LT |
2018 | xfs_btree_offsets(fields, offsets, XFS_AGF_NUM_BITS, &first, &last); |
2019 | xfs_trans_log_buf(tp, bp, (uint)first, (uint)last); | |
2020 | } | |
2021 | ||
2022 | /* | |
2023 | * Interface for inode allocation to force the pag data to be initialized. | |
2024 | */ | |
2025 | int /* error */ | |
2026 | xfs_alloc_pagf_init( | |
2027 | xfs_mount_t *mp, /* file system mount structure */ | |
2028 | xfs_trans_t *tp, /* transaction pointer */ | |
2029 | xfs_agnumber_t agno, /* allocation group number */ | |
2030 | int flags) /* XFS_ALLOC_FLAGS_... */ | |
2031 | { | |
2032 | xfs_buf_t *bp; | |
2033 | int error; | |
2034 | ||
2035 | if ((error = xfs_alloc_read_agf(mp, tp, agno, flags, &bp))) | |
2036 | return error; | |
2037 | if (bp) | |
2038 | xfs_trans_brelse(tp, bp); | |
2039 | return 0; | |
2040 | } | |
2041 | ||
2042 | /* | |
2043 | * Put the block on the freelist for the allocation group. | |
2044 | */ | |
2045 | int /* error */ | |
2046 | xfs_alloc_put_freelist( | |
2047 | xfs_trans_t *tp, /* transaction pointer */ | |
2048 | xfs_buf_t *agbp, /* buffer for a.g. freelist header */ | |
2049 | xfs_buf_t *agflbp,/* buffer for a.g. free block array */ | |
92821e2b DC |
2050 | xfs_agblock_t bno, /* block being freed */ |
2051 | int btreeblk) /* block came from a AGF btree */ | |
1da177e4 LT |
2052 | { |
2053 | xfs_agf_t *agf; /* a.g. freespace structure */ | |
2054 | xfs_agfl_t *agfl; /* a.g. free block array */ | |
e2101005 | 2055 | __be32 *blockp;/* pointer to array entry */ |
1da177e4 | 2056 | int error; |
92821e2b | 2057 | int logflags; |
1da177e4 LT |
2058 | xfs_mount_t *mp; /* mount structure */ |
2059 | xfs_perag_t *pag; /* per allocation group data */ | |
2060 | ||
2061 | agf = XFS_BUF_TO_AGF(agbp); | |
2062 | mp = tp->t_mountp; | |
2063 | ||
2064 | if (!agflbp && (error = xfs_alloc_read_agfl(mp, tp, | |
16259e7d | 2065 | be32_to_cpu(agf->agf_seqno), &agflbp))) |
1da177e4 LT |
2066 | return error; |
2067 | agfl = XFS_BUF_TO_AGFL(agflbp); | |
413d57c9 | 2068 | be32_add_cpu(&agf->agf_fllast, 1); |
16259e7d | 2069 | if (be32_to_cpu(agf->agf_fllast) == XFS_AGFL_SIZE(mp)) |
1da177e4 | 2070 | agf->agf_fllast = 0; |
a862e0fd DC |
2071 | |
2072 | pag = xfs_perag_get(mp, be32_to_cpu(agf->agf_seqno)); | |
413d57c9 | 2073 | be32_add_cpu(&agf->agf_flcount, 1); |
1da177e4 LT |
2074 | xfs_trans_agflist_delta(tp, 1); |
2075 | pag->pagf_flcount++; | |
92821e2b DC |
2076 | |
2077 | logflags = XFS_AGF_FLLAST | XFS_AGF_FLCOUNT; | |
2078 | if (btreeblk) { | |
413d57c9 | 2079 | be32_add_cpu(&agf->agf_btreeblks, -1); |
92821e2b DC |
2080 | pag->pagf_btreeblks--; |
2081 | logflags |= XFS_AGF_BTREEBLKS; | |
2082 | } | |
a862e0fd | 2083 | xfs_perag_put(pag); |
92821e2b | 2084 | |
92821e2b DC |
2085 | xfs_alloc_log_agf(tp, agbp, logflags); |
2086 | ||
16259e7d CH |
2087 | ASSERT(be32_to_cpu(agf->agf_flcount) <= XFS_AGFL_SIZE(mp)); |
2088 | blockp = &agfl->agfl_bno[be32_to_cpu(agf->agf_fllast)]; | |
e2101005 | 2089 | *blockp = cpu_to_be32(bno); |
92821e2b | 2090 | xfs_alloc_log_agf(tp, agbp, logflags); |
1da177e4 LT |
2091 | xfs_trans_log_buf(tp, agflbp, |
2092 | (int)((xfs_caddr_t)blockp - (xfs_caddr_t)agfl), | |
2093 | (int)((xfs_caddr_t)blockp - (xfs_caddr_t)agfl + | |
2094 | sizeof(xfs_agblock_t) - 1)); | |
2095 | return 0; | |
2096 | } | |
2097 | ||
2098 | /* | |
2099 | * Read in the allocation group header (free/alloc section). | |
2100 | */ | |
2101 | int /* error */ | |
4805621a FCH |
2102 | xfs_read_agf( |
2103 | struct xfs_mount *mp, /* mount point structure */ | |
2104 | struct xfs_trans *tp, /* transaction pointer */ | |
2105 | xfs_agnumber_t agno, /* allocation group number */ | |
2106 | int flags, /* XFS_BUF_ */ | |
2107 | struct xfs_buf **bpp) /* buffer for the ag freelist header */ | |
1da177e4 | 2108 | { |
4805621a | 2109 | struct xfs_agf *agf; /* ag freelist header */ |
1da177e4 | 2110 | int agf_ok; /* set if agf is consistent */ |
1da177e4 LT |
2111 | int error; |
2112 | ||
2113 | ASSERT(agno != NULLAGNUMBER); | |
2114 | error = xfs_trans_read_buf( | |
2115 | mp, tp, mp->m_ddev_targp, | |
2116 | XFS_AG_DADDR(mp, agno, XFS_AGF_DADDR(mp)), | |
4805621a | 2117 | XFS_FSS_TO_BB(mp, 1), flags, bpp); |
1da177e4 LT |
2118 | if (error) |
2119 | return error; | |
4805621a | 2120 | if (!*bpp) |
1da177e4 | 2121 | return 0; |
4805621a FCH |
2122 | |
2123 | ASSERT(!XFS_BUF_GETERROR(*bpp)); | |
2124 | agf = XFS_BUF_TO_AGF(*bpp); | |
2125 | ||
1da177e4 LT |
2126 | /* |
2127 | * Validate the magic number of the agf block. | |
2128 | */ | |
1da177e4 | 2129 | agf_ok = |
16259e7d CH |
2130 | be32_to_cpu(agf->agf_magicnum) == XFS_AGF_MAGIC && |
2131 | XFS_AGF_GOOD_VERSION(be32_to_cpu(agf->agf_versionnum)) && | |
2132 | be32_to_cpu(agf->agf_freeblks) <= be32_to_cpu(agf->agf_length) && | |
2133 | be32_to_cpu(agf->agf_flfirst) < XFS_AGFL_SIZE(mp) && | |
2134 | be32_to_cpu(agf->agf_fllast) < XFS_AGFL_SIZE(mp) && | |
4805621a FCH |
2135 | be32_to_cpu(agf->agf_flcount) <= XFS_AGFL_SIZE(mp) && |
2136 | be32_to_cpu(agf->agf_seqno) == agno; | |
89b28393 BN |
2137 | if (xfs_sb_version_haslazysbcount(&mp->m_sb)) |
2138 | agf_ok = agf_ok && be32_to_cpu(agf->agf_btreeblks) <= | |
2139 | be32_to_cpu(agf->agf_length); | |
1da177e4 LT |
2140 | if (unlikely(XFS_TEST_ERROR(!agf_ok, mp, XFS_ERRTAG_ALLOC_READ_AGF, |
2141 | XFS_RANDOM_ALLOC_READ_AGF))) { | |
2142 | XFS_CORRUPTION_ERROR("xfs_alloc_read_agf", | |
2143 | XFS_ERRLEVEL_LOW, mp, agf); | |
4805621a | 2144 | xfs_trans_brelse(tp, *bpp); |
1da177e4 LT |
2145 | return XFS_ERROR(EFSCORRUPTED); |
2146 | } | |
4805621a FCH |
2147 | XFS_BUF_SET_VTYPE_REF(*bpp, B_FS_AGF, XFS_AGF_REF); |
2148 | return 0; | |
2149 | } | |
2150 | ||
2151 | /* | |
2152 | * Read in the allocation group header (free/alloc section). | |
2153 | */ | |
2154 | int /* error */ | |
2155 | xfs_alloc_read_agf( | |
2156 | struct xfs_mount *mp, /* mount point structure */ | |
2157 | struct xfs_trans *tp, /* transaction pointer */ | |
2158 | xfs_agnumber_t agno, /* allocation group number */ | |
2159 | int flags, /* XFS_ALLOC_FLAG_... */ | |
2160 | struct xfs_buf **bpp) /* buffer for the ag freelist header */ | |
2161 | { | |
2162 | struct xfs_agf *agf; /* ag freelist header */ | |
2163 | struct xfs_perag *pag; /* per allocation group data */ | |
2164 | int error; | |
2165 | ||
2166 | ASSERT(agno != NULLAGNUMBER); | |
2167 | ||
2168 | error = xfs_read_agf(mp, tp, agno, | |
0cadda1c | 2169 | (flags & XFS_ALLOC_FLAG_TRYLOCK) ? XBF_TRYLOCK : 0, |
4805621a FCH |
2170 | bpp); |
2171 | if (error) | |
2172 | return error; | |
2173 | if (!*bpp) | |
2174 | return 0; | |
2175 | ASSERT(!XFS_BUF_GETERROR(*bpp)); | |
2176 | ||
2177 | agf = XFS_BUF_TO_AGF(*bpp); | |
a862e0fd | 2178 | pag = xfs_perag_get(mp, agno); |
1da177e4 | 2179 | if (!pag->pagf_init) { |
16259e7d | 2180 | pag->pagf_freeblks = be32_to_cpu(agf->agf_freeblks); |
92821e2b | 2181 | pag->pagf_btreeblks = be32_to_cpu(agf->agf_btreeblks); |
16259e7d CH |
2182 | pag->pagf_flcount = be32_to_cpu(agf->agf_flcount); |
2183 | pag->pagf_longest = be32_to_cpu(agf->agf_longest); | |
1da177e4 | 2184 | pag->pagf_levels[XFS_BTNUM_BNOi] = |
16259e7d | 2185 | be32_to_cpu(agf->agf_levels[XFS_BTNUM_BNOi]); |
1da177e4 | 2186 | pag->pagf_levels[XFS_BTNUM_CNTi] = |
16259e7d | 2187 | be32_to_cpu(agf->agf_levels[XFS_BTNUM_CNTi]); |
007c61c6 | 2188 | spin_lock_init(&pag->pagb_lock); |
e57336ff | 2189 | pag->pagb_count = 0; |
ed3b4d6c | 2190 | pag->pagb_tree = RB_ROOT; |
1da177e4 LT |
2191 | pag->pagf_init = 1; |
2192 | } | |
2193 | #ifdef DEBUG | |
2194 | else if (!XFS_FORCED_SHUTDOWN(mp)) { | |
16259e7d | 2195 | ASSERT(pag->pagf_freeblks == be32_to_cpu(agf->agf_freeblks)); |
89b28393 | 2196 | ASSERT(pag->pagf_btreeblks == be32_to_cpu(agf->agf_btreeblks)); |
16259e7d CH |
2197 | ASSERT(pag->pagf_flcount == be32_to_cpu(agf->agf_flcount)); |
2198 | ASSERT(pag->pagf_longest == be32_to_cpu(agf->agf_longest)); | |
1da177e4 | 2199 | ASSERT(pag->pagf_levels[XFS_BTNUM_BNOi] == |
16259e7d | 2200 | be32_to_cpu(agf->agf_levels[XFS_BTNUM_BNOi])); |
1da177e4 | 2201 | ASSERT(pag->pagf_levels[XFS_BTNUM_CNTi] == |
16259e7d | 2202 | be32_to_cpu(agf->agf_levels[XFS_BTNUM_CNTi])); |
1da177e4 LT |
2203 | } |
2204 | #endif | |
a862e0fd | 2205 | xfs_perag_put(pag); |
1da177e4 LT |
2206 | return 0; |
2207 | } | |
2208 | ||
2209 | /* | |
2210 | * Allocate an extent (variable-size). | |
2211 | * Depending on the allocation type, we either look in a single allocation | |
2212 | * group or loop over the allocation groups to find the result. | |
2213 | */ | |
2214 | int /* error */ | |
2215 | xfs_alloc_vextent( | |
2216 | xfs_alloc_arg_t *args) /* allocation argument structure */ | |
2217 | { | |
2218 | xfs_agblock_t agsize; /* allocation group size */ | |
2219 | int error; | |
2220 | int flags; /* XFS_ALLOC_FLAG_... locking flags */ | |
1da177e4 LT |
2221 | xfs_extlen_t minleft;/* minimum left value, temp copy */ |
2222 | xfs_mount_t *mp; /* mount structure pointer */ | |
2223 | xfs_agnumber_t sagno; /* starting allocation group number */ | |
2224 | xfs_alloctype_t type; /* input allocation type */ | |
2225 | int bump_rotor = 0; | |
2226 | int no_min = 0; | |
2227 | xfs_agnumber_t rotorstep = xfs_rotorstep; /* inode32 agf stepper */ | |
2228 | ||
2229 | mp = args->mp; | |
2230 | type = args->otype = args->type; | |
2231 | args->agbno = NULLAGBLOCK; | |
2232 | /* | |
2233 | * Just fix this up, for the case where the last a.g. is shorter | |
2234 | * (or there's only one a.g.) and the caller couldn't easily figure | |
2235 | * that out (xfs_bmap_alloc). | |
2236 | */ | |
2237 | agsize = mp->m_sb.sb_agblocks; | |
2238 | if (args->maxlen > agsize) | |
2239 | args->maxlen = agsize; | |
2240 | if (args->alignment == 0) | |
2241 | args->alignment = 1; | |
2242 | ASSERT(XFS_FSB_TO_AGNO(mp, args->fsbno) < mp->m_sb.sb_agcount); | |
2243 | ASSERT(XFS_FSB_TO_AGBNO(mp, args->fsbno) < agsize); | |
2244 | ASSERT(args->minlen <= args->maxlen); | |
2245 | ASSERT(args->minlen <= agsize); | |
2246 | ASSERT(args->mod < args->prod); | |
2247 | if (XFS_FSB_TO_AGNO(mp, args->fsbno) >= mp->m_sb.sb_agcount || | |
2248 | XFS_FSB_TO_AGBNO(mp, args->fsbno) >= agsize || | |
2249 | args->minlen > args->maxlen || args->minlen > agsize || | |
2250 | args->mod >= args->prod) { | |
2251 | args->fsbno = NULLFSBLOCK; | |
0b1b213f | 2252 | trace_xfs_alloc_vextent_badargs(args); |
1da177e4 LT |
2253 | return 0; |
2254 | } | |
2255 | minleft = args->minleft; | |
2256 | ||
2257 | switch (type) { | |
2258 | case XFS_ALLOCTYPE_THIS_AG: | |
2259 | case XFS_ALLOCTYPE_NEAR_BNO: | |
2260 | case XFS_ALLOCTYPE_THIS_BNO: | |
2261 | /* | |
2262 | * These three force us into a single a.g. | |
2263 | */ | |
2264 | args->agno = XFS_FSB_TO_AGNO(mp, args->fsbno); | |
a862e0fd | 2265 | args->pag = xfs_perag_get(mp, args->agno); |
1da177e4 LT |
2266 | args->minleft = 0; |
2267 | error = xfs_alloc_fix_freelist(args, 0); | |
2268 | args->minleft = minleft; | |
2269 | if (error) { | |
0b1b213f | 2270 | trace_xfs_alloc_vextent_nofix(args); |
1da177e4 LT |
2271 | goto error0; |
2272 | } | |
2273 | if (!args->agbp) { | |
0b1b213f | 2274 | trace_xfs_alloc_vextent_noagbp(args); |
1da177e4 LT |
2275 | break; |
2276 | } | |
2277 | args->agbno = XFS_FSB_TO_AGBNO(mp, args->fsbno); | |
2278 | if ((error = xfs_alloc_ag_vextent(args))) | |
2279 | goto error0; | |
1da177e4 LT |
2280 | break; |
2281 | case XFS_ALLOCTYPE_START_BNO: | |
2282 | /* | |
2283 | * Try near allocation first, then anywhere-in-ag after | |
2284 | * the first a.g. fails. | |
2285 | */ | |
2286 | if ((args->userdata == XFS_ALLOC_INITIAL_USER_DATA) && | |
2287 | (mp->m_flags & XFS_MOUNT_32BITINODES)) { | |
2288 | args->fsbno = XFS_AGB_TO_FSB(mp, | |
2289 | ((mp->m_agfrotor / rotorstep) % | |
2290 | mp->m_sb.sb_agcount), 0); | |
2291 | bump_rotor = 1; | |
2292 | } | |
2293 | args->agbno = XFS_FSB_TO_AGBNO(mp, args->fsbno); | |
2294 | args->type = XFS_ALLOCTYPE_NEAR_BNO; | |
2295 | /* FALLTHROUGH */ | |
2296 | case XFS_ALLOCTYPE_ANY_AG: | |
2297 | case XFS_ALLOCTYPE_START_AG: | |
2298 | case XFS_ALLOCTYPE_FIRST_AG: | |
2299 | /* | |
2300 | * Rotate through the allocation groups looking for a winner. | |
2301 | */ | |
2302 | if (type == XFS_ALLOCTYPE_ANY_AG) { | |
2303 | /* | |
2304 | * Start with the last place we left off. | |
2305 | */ | |
2306 | args->agno = sagno = (mp->m_agfrotor / rotorstep) % | |
2307 | mp->m_sb.sb_agcount; | |
2308 | args->type = XFS_ALLOCTYPE_THIS_AG; | |
2309 | flags = XFS_ALLOC_FLAG_TRYLOCK; | |
2310 | } else if (type == XFS_ALLOCTYPE_FIRST_AG) { | |
2311 | /* | |
2312 | * Start with allocation group given by bno. | |
2313 | */ | |
2314 | args->agno = XFS_FSB_TO_AGNO(mp, args->fsbno); | |
2315 | args->type = XFS_ALLOCTYPE_THIS_AG; | |
2316 | sagno = 0; | |
2317 | flags = 0; | |
2318 | } else { | |
2319 | if (type == XFS_ALLOCTYPE_START_AG) | |
2320 | args->type = XFS_ALLOCTYPE_THIS_AG; | |
2321 | /* | |
2322 | * Start with the given allocation group. | |
2323 | */ | |
2324 | args->agno = sagno = XFS_FSB_TO_AGNO(mp, args->fsbno); | |
2325 | flags = XFS_ALLOC_FLAG_TRYLOCK; | |
2326 | } | |
2327 | /* | |
2328 | * Loop over allocation groups twice; first time with | |
2329 | * trylock set, second time without. | |
2330 | */ | |
1da177e4 | 2331 | for (;;) { |
a862e0fd | 2332 | args->pag = xfs_perag_get(mp, args->agno); |
1da177e4 LT |
2333 | if (no_min) args->minleft = 0; |
2334 | error = xfs_alloc_fix_freelist(args, flags); | |
2335 | args->minleft = minleft; | |
2336 | if (error) { | |
0b1b213f | 2337 | trace_xfs_alloc_vextent_nofix(args); |
1da177e4 LT |
2338 | goto error0; |
2339 | } | |
2340 | /* | |
2341 | * If we get a buffer back then the allocation will fly. | |
2342 | */ | |
2343 | if (args->agbp) { | |
2344 | if ((error = xfs_alloc_ag_vextent(args))) | |
2345 | goto error0; | |
2346 | break; | |
2347 | } | |
0b1b213f CH |
2348 | |
2349 | trace_xfs_alloc_vextent_loopfailed(args); | |
2350 | ||
1da177e4 LT |
2351 | /* |
2352 | * Didn't work, figure out the next iteration. | |
2353 | */ | |
2354 | if (args->agno == sagno && | |
2355 | type == XFS_ALLOCTYPE_START_BNO) | |
2356 | args->type = XFS_ALLOCTYPE_THIS_AG; | |
d210a28c YL |
2357 | /* |
2358 | * For the first allocation, we can try any AG to get | |
2359 | * space. However, if we already have allocated a | |
2360 | * block, we don't want to try AGs whose number is below | |
2361 | * sagno. Otherwise, we may end up with out-of-order | |
2362 | * locking of AGF, which might cause deadlock. | |
2363 | */ | |
2364 | if (++(args->agno) == mp->m_sb.sb_agcount) { | |
2365 | if (args->firstblock != NULLFSBLOCK) | |
2366 | args->agno = sagno; | |
2367 | else | |
2368 | args->agno = 0; | |
2369 | } | |
1da177e4 LT |
2370 | /* |
2371 | * Reached the starting a.g., must either be done | |
2372 | * or switch to non-trylock mode. | |
2373 | */ | |
2374 | if (args->agno == sagno) { | |
2375 | if (no_min == 1) { | |
2376 | args->agbno = NULLAGBLOCK; | |
0b1b213f | 2377 | trace_xfs_alloc_vextent_allfailed(args); |
1da177e4 LT |
2378 | break; |
2379 | } | |
2380 | if (flags == 0) { | |
2381 | no_min = 1; | |
2382 | } else { | |
2383 | flags = 0; | |
2384 | if (type == XFS_ALLOCTYPE_START_BNO) { | |
2385 | args->agbno = XFS_FSB_TO_AGBNO(mp, | |
2386 | args->fsbno); | |
2387 | args->type = XFS_ALLOCTYPE_NEAR_BNO; | |
2388 | } | |
2389 | } | |
2390 | } | |
a862e0fd | 2391 | xfs_perag_put(args->pag); |
1da177e4 | 2392 | } |
1da177e4 LT |
2393 | if (bump_rotor || (type == XFS_ALLOCTYPE_ANY_AG)) { |
2394 | if (args->agno == sagno) | |
2395 | mp->m_agfrotor = (mp->m_agfrotor + 1) % | |
2396 | (mp->m_sb.sb_agcount * rotorstep); | |
2397 | else | |
2398 | mp->m_agfrotor = (args->agno * rotorstep + 1) % | |
2399 | (mp->m_sb.sb_agcount * rotorstep); | |
2400 | } | |
2401 | break; | |
2402 | default: | |
2403 | ASSERT(0); | |
2404 | /* NOTREACHED */ | |
2405 | } | |
2406 | if (args->agbno == NULLAGBLOCK) | |
2407 | args->fsbno = NULLFSBLOCK; | |
2408 | else { | |
2409 | args->fsbno = XFS_AGB_TO_FSB(mp, args->agno, args->agbno); | |
2410 | #ifdef DEBUG | |
2411 | ASSERT(args->len >= args->minlen); | |
2412 | ASSERT(args->len <= args->maxlen); | |
2413 | ASSERT(args->agbno % args->alignment == 0); | |
2414 | XFS_AG_CHECK_DADDR(mp, XFS_FSB_TO_DADDR(mp, args->fsbno), | |
2415 | args->len); | |
2416 | #endif | |
2417 | } | |
a862e0fd | 2418 | xfs_perag_put(args->pag); |
1da177e4 LT |
2419 | return 0; |
2420 | error0: | |
a862e0fd | 2421 | xfs_perag_put(args->pag); |
1da177e4 LT |
2422 | return error; |
2423 | } | |
2424 | ||
2425 | /* | |
2426 | * Free an extent. | |
2427 | * Just break up the extent address and hand off to xfs_free_ag_extent | |
2428 | * after fixing up the freelist. | |
2429 | */ | |
2430 | int /* error */ | |
2431 | xfs_free_extent( | |
2432 | xfs_trans_t *tp, /* transaction pointer */ | |
2433 | xfs_fsblock_t bno, /* starting block number of extent */ | |
2434 | xfs_extlen_t len) /* length of extent */ | |
2435 | { | |
0e1edbd9 | 2436 | xfs_alloc_arg_t args; |
1da177e4 LT |
2437 | int error; |
2438 | ||
2439 | ASSERT(len != 0); | |
0e1edbd9 | 2440 | memset(&args, 0, sizeof(xfs_alloc_arg_t)); |
1da177e4 LT |
2441 | args.tp = tp; |
2442 | args.mp = tp->t_mountp; | |
be65b18a DC |
2443 | |
2444 | /* | |
2445 | * validate that the block number is legal - the enables us to detect | |
2446 | * and handle a silent filesystem corruption rather than crashing. | |
2447 | */ | |
1da177e4 | 2448 | args.agno = XFS_FSB_TO_AGNO(args.mp, bno); |
be65b18a DC |
2449 | if (args.agno >= args.mp->m_sb.sb_agcount) |
2450 | return EFSCORRUPTED; | |
2451 | ||
1da177e4 | 2452 | args.agbno = XFS_FSB_TO_AGBNO(args.mp, bno); |
be65b18a DC |
2453 | if (args.agbno >= args.mp->m_sb.sb_agblocks) |
2454 | return EFSCORRUPTED; | |
2455 | ||
a862e0fd | 2456 | args.pag = xfs_perag_get(args.mp, args.agno); |
be65b18a DC |
2457 | ASSERT(args.pag); |
2458 | ||
2459 | error = xfs_alloc_fix_freelist(&args, XFS_ALLOC_FLAG_FREEING); | |
2460 | if (error) | |
1da177e4 | 2461 | goto error0; |
be65b18a DC |
2462 | |
2463 | /* validate the extent size is legal now we have the agf locked */ | |
2464 | if (args.agbno + len > | |
2465 | be32_to_cpu(XFS_BUF_TO_AGF(args.agbp)->agf_length)) { | |
2466 | error = EFSCORRUPTED; | |
2467 | goto error0; | |
2468 | } | |
2469 | ||
0e1edbd9 | 2470 | error = xfs_free_ag_extent(tp, args.agbp, args.agno, args.agbno, len, 0); |
a870acd9 | 2471 | if (!error) |
55a7bc5a | 2472 | xfs_alloc_busy_insert(tp, args.agno, args.agbno, len, 0); |
1da177e4 | 2473 | error0: |
a862e0fd | 2474 | xfs_perag_put(args.pag); |
1da177e4 LT |
2475 | return error; |
2476 | } | |
2477 | ||
1da177e4 | 2478 | void |
ed3b4d6c DC |
2479 | xfs_alloc_busy_insert( |
2480 | struct xfs_trans *tp, | |
2481 | xfs_agnumber_t agno, | |
2482 | xfs_agblock_t bno, | |
55a7bc5a CH |
2483 | xfs_extlen_t len, |
2484 | unsigned int flags) | |
1da177e4 | 2485 | { |
ed3b4d6c DC |
2486 | struct xfs_busy_extent *new; |
2487 | struct xfs_busy_extent *busyp; | |
a862e0fd | 2488 | struct xfs_perag *pag; |
ed3b4d6c | 2489 | struct rb_node **rbp; |
97d3ac75 | 2490 | struct rb_node *parent = NULL; |
1da177e4 | 2491 | |
ed3b4d6c DC |
2492 | new = kmem_zalloc(sizeof(struct xfs_busy_extent), KM_MAYFAIL); |
2493 | if (!new) { | |
2494 | /* | |
2495 | * No Memory! Since it is now not possible to track the free | |
2496 | * block, make this a synchronous transaction to insure that | |
2497 | * the block is not reused before this transaction commits. | |
2498 | */ | |
97d3ac75 | 2499 | trace_xfs_alloc_busy_enomem(tp->t_mountp, agno, bno, len); |
ed3b4d6c DC |
2500 | xfs_trans_set_sync(tp); |
2501 | return; | |
1da177e4 LT |
2502 | } |
2503 | ||
ed3b4d6c DC |
2504 | new->agno = agno; |
2505 | new->bno = bno; | |
2506 | new->length = len; | |
ed3b4d6c | 2507 | INIT_LIST_HEAD(&new->list); |
55a7bc5a | 2508 | new->flags = flags; |
ed3b4d6c DC |
2509 | |
2510 | /* trace before insert to be able to see failed inserts */ | |
97d3ac75 | 2511 | trace_xfs_alloc_busy(tp->t_mountp, agno, bno, len); |
ed3b4d6c DC |
2512 | |
2513 | pag = xfs_perag_get(tp->t_mountp, new->agno); | |
ed3b4d6c DC |
2514 | spin_lock(&pag->pagb_lock); |
2515 | rbp = &pag->pagb_tree.rb_node; | |
97d3ac75 | 2516 | while (*rbp) { |
ed3b4d6c DC |
2517 | parent = *rbp; |
2518 | busyp = rb_entry(parent, struct xfs_busy_extent, rb_node); | |
2519 | ||
2520 | if (new->bno < busyp->bno) { | |
ed3b4d6c | 2521 | rbp = &(*rbp)->rb_left; |
97d3ac75 | 2522 | ASSERT(new->bno + new->length <= busyp->bno); |
ed3b4d6c | 2523 | } else if (new->bno > busyp->bno) { |
ed3b4d6c | 2524 | rbp = &(*rbp)->rb_right; |
97d3ac75 | 2525 | ASSERT(bno >= busyp->bno + busyp->length); |
ed3b4d6c | 2526 | } else { |
97d3ac75 | 2527 | ASSERT(0); |
ed3b4d6c DC |
2528 | } |
2529 | } | |
1da177e4 | 2530 | |
ed3b4d6c DC |
2531 | rb_link_node(&new->rb_node, parent, rbp); |
2532 | rb_insert_color(&new->rb_node, &pag->pagb_tree); | |
2533 | ||
2534 | list_add(&new->list, &tp->t_busy); | |
a862e0fd DC |
2535 | spin_unlock(&pag->pagb_lock); |
2536 | xfs_perag_put(pag); | |
1da177e4 LT |
2537 | } |
2538 | ||
ed3b4d6c DC |
2539 | /* |
2540 | * Search for a busy extent within the range of the extent we are about to | |
2541 | * allocate. You need to be holding the busy extent tree lock when calling | |
2542 | * xfs_alloc_busy_search(). This function returns 0 for no overlapping busy | |
2543 | * extent, -1 for an overlapping but not exact busy extent, and 1 for an exact | |
2544 | * match. This is done so that a non-zero return indicates an overlap that | |
2545 | * will require a synchronous transaction, but it can still be | |
2546 | * used to distinguish between a partial or exact match. | |
2547 | */ | |
a46db608 | 2548 | int |
ed3b4d6c DC |
2549 | xfs_alloc_busy_search( |
2550 | struct xfs_mount *mp, | |
2551 | xfs_agnumber_t agno, | |
2552 | xfs_agblock_t bno, | |
2553 | xfs_extlen_t len) | |
1da177e4 | 2554 | { |
a862e0fd | 2555 | struct xfs_perag *pag; |
ed3b4d6c DC |
2556 | struct rb_node *rbp; |
2557 | struct xfs_busy_extent *busyp; | |
2558 | int match = 0; | |
1da177e4 | 2559 | |
ed3b4d6c | 2560 | pag = xfs_perag_get(mp, agno); |
a862e0fd | 2561 | spin_lock(&pag->pagb_lock); |
0b1b213f | 2562 | |
ed3b4d6c DC |
2563 | rbp = pag->pagb_tree.rb_node; |
2564 | ||
2565 | /* find closest start bno overlap */ | |
2566 | while (rbp) { | |
2567 | busyp = rb_entry(rbp, struct xfs_busy_extent, rb_node); | |
2568 | if (bno < busyp->bno) { | |
2569 | /* may overlap, but exact start block is lower */ | |
2570 | if (bno + len > busyp->bno) | |
2571 | match = -1; | |
2572 | rbp = rbp->rb_left; | |
2573 | } else if (bno > busyp->bno) { | |
2574 | /* may overlap, but exact start block is higher */ | |
2575 | if (bno < busyp->bno + busyp->length) | |
2576 | match = -1; | |
2577 | rbp = rbp->rb_right; | |
2578 | } else { | |
2579 | /* bno matches busyp, length determines exact match */ | |
2580 | match = (busyp->length == len) ? 1 : -1; | |
2581 | break; | |
2582 | } | |
1da177e4 | 2583 | } |
a862e0fd DC |
2584 | spin_unlock(&pag->pagb_lock); |
2585 | xfs_perag_put(pag); | |
ed3b4d6c | 2586 | return match; |
1da177e4 LT |
2587 | } |
2588 | ||
97d3ac75 CH |
2589 | /* |
2590 | * The found free extent [fbno, fend] overlaps part or all of the given busy | |
2591 | * extent. If the overlap covers the beginning, the end, or all of the busy | |
2592 | * extent, the overlapping portion can be made unbusy and used for the | |
2593 | * allocation. We can't split a busy extent because we can't modify a | |
2594 | * transaction/CIL context busy list, but we can update an entries block | |
2595 | * number or length. | |
2596 | * | |
2597 | * Returns true if the extent can safely be reused, or false if the search | |
2598 | * needs to be restarted. | |
2599 | */ | |
2600 | STATIC bool | |
2601 | xfs_alloc_busy_update_extent( | |
2602 | struct xfs_mount *mp, | |
2603 | struct xfs_perag *pag, | |
2604 | struct xfs_busy_extent *busyp, | |
2605 | xfs_agblock_t fbno, | |
2606 | xfs_extlen_t flen, | |
2607 | bool userdata) | |
2608 | { | |
2609 | xfs_agblock_t fend = fbno + flen; | |
2610 | xfs_agblock_t bbno = busyp->bno; | |
2611 | xfs_agblock_t bend = bbno + busyp->length; | |
2612 | ||
e84661aa CH |
2613 | /* |
2614 | * This extent is currently being discarded. Give the thread | |
2615 | * performing the discard a chance to mark the extent unbusy | |
2616 | * and retry. | |
2617 | */ | |
2618 | if (busyp->flags & XFS_ALLOC_BUSY_DISCARDED) { | |
2619 | spin_unlock(&pag->pagb_lock); | |
2620 | delay(1); | |
2621 | spin_lock(&pag->pagb_lock); | |
2622 | return false; | |
2623 | } | |
2624 | ||
97d3ac75 CH |
2625 | /* |
2626 | * If there is a busy extent overlapping a user allocation, we have | |
2627 | * no choice but to force the log and retry the search. | |
2628 | * | |
2629 | * Fortunately this does not happen during normal operation, but | |
2630 | * only if the filesystem is very low on space and has to dip into | |
2631 | * the AGFL for normal allocations. | |
2632 | */ | |
2633 | if (userdata) | |
2634 | goto out_force_log; | |
2635 | ||
2636 | if (bbno < fbno && bend > fend) { | |
2637 | /* | |
2638 | * Case 1: | |
2639 | * bbno bend | |
2640 | * +BBBBBBBBBBBBBBBBB+ | |
2641 | * +---------+ | |
2642 | * fbno fend | |
2643 | */ | |
2644 | ||
2645 | /* | |
2646 | * We would have to split the busy extent to be able to track | |
2647 | * it correct, which we cannot do because we would have to | |
2648 | * modify the list of busy extents attached to the transaction | |
2649 | * or CIL context, which is immutable. | |
2650 | * | |
2651 | * Force out the log to clear the busy extent and retry the | |
2652 | * search. | |
2653 | */ | |
2654 | goto out_force_log; | |
2655 | } else if (bbno >= fbno && bend <= fend) { | |
2656 | /* | |
2657 | * Case 2: | |
2658 | * bbno bend | |
2659 | * +BBBBBBBBBBBBBBBBB+ | |
2660 | * +-----------------+ | |
2661 | * fbno fend | |
2662 | * | |
2663 | * Case 3: | |
2664 | * bbno bend | |
2665 | * +BBBBBBBBBBBBBBBBB+ | |
2666 | * +--------------------------+ | |
2667 | * fbno fend | |
2668 | * | |
2669 | * Case 4: | |
2670 | * bbno bend | |
2671 | * +BBBBBBBBBBBBBBBBB+ | |
2672 | * +--------------------------+ | |
2673 | * fbno fend | |
2674 | * | |
2675 | * Case 5: | |
2676 | * bbno bend | |
2677 | * +BBBBBBBBBBBBBBBBB+ | |
2678 | * +-----------------------------------+ | |
2679 | * fbno fend | |
2680 | * | |
2681 | */ | |
2682 | ||
2683 | /* | |
2684 | * The busy extent is fully covered by the extent we are | |
2685 | * allocating, and can simply be removed from the rbtree. | |
2686 | * However we cannot remove it from the immutable list | |
2687 | * tracking busy extents in the transaction or CIL context, | |
2688 | * so set the length to zero to mark it invalid. | |
2689 | * | |
2690 | * We also need to restart the busy extent search from the | |
2691 | * tree root, because erasing the node can rearrange the | |
2692 | * tree topology. | |
2693 | */ | |
2694 | rb_erase(&busyp->rb_node, &pag->pagb_tree); | |
2695 | busyp->length = 0; | |
2696 | return false; | |
2697 | } else if (fend < bend) { | |
2698 | /* | |
2699 | * Case 6: | |
2700 | * bbno bend | |
2701 | * +BBBBBBBBBBBBBBBBB+ | |
2702 | * +---------+ | |
2703 | * fbno fend | |
2704 | * | |
2705 | * Case 7: | |
2706 | * bbno bend | |
2707 | * +BBBBBBBBBBBBBBBBB+ | |
2708 | * +------------------+ | |
2709 | * fbno fend | |
2710 | * | |
2711 | */ | |
2712 | busyp->bno = fend; | |
2713 | } else if (bbno < fbno) { | |
2714 | /* | |
2715 | * Case 8: | |
2716 | * bbno bend | |
2717 | * +BBBBBBBBBBBBBBBBB+ | |
2718 | * +-------------+ | |
2719 | * fbno fend | |
2720 | * | |
2721 | * Case 9: | |
2722 | * bbno bend | |
2723 | * +BBBBBBBBBBBBBBBBB+ | |
2724 | * +----------------------+ | |
2725 | * fbno fend | |
2726 | */ | |
2727 | busyp->length = fbno - busyp->bno; | |
2728 | } else { | |
2729 | ASSERT(0); | |
2730 | } | |
2731 | ||
2732 | trace_xfs_alloc_busy_reuse(mp, pag->pag_agno, fbno, flen); | |
2733 | return true; | |
2734 | ||
2735 | out_force_log: | |
2736 | spin_unlock(&pag->pagb_lock); | |
2737 | xfs_log_force(mp, XFS_LOG_SYNC); | |
2738 | trace_xfs_alloc_busy_force(mp, pag->pag_agno, fbno, flen); | |
2739 | spin_lock(&pag->pagb_lock); | |
2740 | return false; | |
2741 | } | |
2742 | ||
2743 | ||
2744 | /* | |
2745 | * For a given extent [fbno, flen], make sure we can reuse it safely. | |
2746 | */ | |
2747 | void | |
2748 | xfs_alloc_busy_reuse( | |
2749 | struct xfs_mount *mp, | |
2750 | xfs_agnumber_t agno, | |
2751 | xfs_agblock_t fbno, | |
2752 | xfs_extlen_t flen, | |
2753 | bool userdata) | |
2754 | { | |
2755 | struct xfs_perag *pag; | |
2756 | struct rb_node *rbp; | |
2757 | ||
2758 | ASSERT(flen > 0); | |
2759 | ||
2760 | pag = xfs_perag_get(mp, agno); | |
2761 | spin_lock(&pag->pagb_lock); | |
2762 | restart: | |
2763 | rbp = pag->pagb_tree.rb_node; | |
2764 | while (rbp) { | |
2765 | struct xfs_busy_extent *busyp = | |
2766 | rb_entry(rbp, struct xfs_busy_extent, rb_node); | |
2767 | xfs_agblock_t bbno = busyp->bno; | |
2768 | xfs_agblock_t bend = bbno + busyp->length; | |
2769 | ||
2770 | if (fbno + flen <= bbno) { | |
2771 | rbp = rbp->rb_left; | |
2772 | continue; | |
2773 | } else if (fbno >= bend) { | |
2774 | rbp = rbp->rb_right; | |
2775 | continue; | |
2776 | } | |
2777 | ||
2778 | if (!xfs_alloc_busy_update_extent(mp, pag, busyp, fbno, flen, | |
2779 | userdata)) | |
2780 | goto restart; | |
2781 | } | |
2782 | spin_unlock(&pag->pagb_lock); | |
2783 | xfs_perag_put(pag); | |
2784 | } | |
2785 | ||
e26f0501 CH |
2786 | /* |
2787 | * For a given extent [fbno, flen], search the busy extent list to find a | |
2788 | * subset of the extent that is not busy. If *rlen is smaller than | |
2789 | * args->minlen no suitable extent could be found, and the higher level | |
2790 | * code needs to force out the log and retry the allocation. | |
2791 | */ | |
2792 | STATIC void | |
2793 | xfs_alloc_busy_trim( | |
2794 | struct xfs_alloc_arg *args, | |
2795 | xfs_agblock_t bno, | |
2796 | xfs_extlen_t len, | |
2797 | xfs_agblock_t *rbno, | |
2798 | xfs_extlen_t *rlen) | |
2799 | { | |
97d3ac75 CH |
2800 | xfs_agblock_t fbno; |
2801 | xfs_extlen_t flen; | |
e26f0501 CH |
2802 | struct rb_node *rbp; |
2803 | ||
97d3ac75 | 2804 | ASSERT(len > 0); |
e26f0501 CH |
2805 | |
2806 | spin_lock(&args->pag->pagb_lock); | |
97d3ac75 CH |
2807 | restart: |
2808 | fbno = bno; | |
2809 | flen = len; | |
e26f0501 CH |
2810 | rbp = args->pag->pagb_tree.rb_node; |
2811 | while (rbp && flen >= args->minlen) { | |
2812 | struct xfs_busy_extent *busyp = | |
2813 | rb_entry(rbp, struct xfs_busy_extent, rb_node); | |
2814 | xfs_agblock_t fend = fbno + flen; | |
2815 | xfs_agblock_t bbno = busyp->bno; | |
2816 | xfs_agblock_t bend = bbno + busyp->length; | |
2817 | ||
2818 | if (fend <= bbno) { | |
2819 | rbp = rbp->rb_left; | |
2820 | continue; | |
2821 | } else if (fbno >= bend) { | |
2822 | rbp = rbp->rb_right; | |
2823 | continue; | |
2824 | } | |
2825 | ||
97d3ac75 CH |
2826 | /* |
2827 | * If this is a metadata allocation, try to reuse the busy | |
2828 | * extent instead of trimming the allocation. | |
2829 | */ | |
e84661aa CH |
2830 | if (!args->userdata && |
2831 | !(busyp->flags & XFS_ALLOC_BUSY_DISCARDED)) { | |
97d3ac75 CH |
2832 | if (!xfs_alloc_busy_update_extent(args->mp, args->pag, |
2833 | busyp, fbno, flen, | |
2834 | false)) | |
2835 | goto restart; | |
2836 | continue; | |
2837 | } | |
2838 | ||
e26f0501 CH |
2839 | if (bbno <= fbno) { |
2840 | /* start overlap */ | |
2841 | ||
2842 | /* | |
2843 | * Case 1: | |
2844 | * bbno bend | |
2845 | * +BBBBBBBBBBBBBBBBB+ | |
2846 | * +---------+ | |
2847 | * fbno fend | |
2848 | * | |
2849 | * Case 2: | |
2850 | * bbno bend | |
2851 | * +BBBBBBBBBBBBBBBBB+ | |
2852 | * +-------------+ | |
2853 | * fbno fend | |
2854 | * | |
2855 | * Case 3: | |
2856 | * bbno bend | |
2857 | * +BBBBBBBBBBBBBBBBB+ | |
2858 | * +-------------+ | |
2859 | * fbno fend | |
2860 | * | |
2861 | * Case 4: | |
2862 | * bbno bend | |
2863 | * +BBBBBBBBBBBBBBBBB+ | |
2864 | * +-----------------+ | |
2865 | * fbno fend | |
2866 | * | |
2867 | * No unbusy region in extent, return failure. | |
2868 | */ | |
2869 | if (fend <= bend) | |
2870 | goto fail; | |
2871 | ||
2872 | /* | |
2873 | * Case 5: | |
2874 | * bbno bend | |
2875 | * +BBBBBBBBBBBBBBBBB+ | |
2876 | * +----------------------+ | |
2877 | * fbno fend | |
2878 | * | |
2879 | * Case 6: | |
2880 | * bbno bend | |
2881 | * +BBBBBBBBBBBBBBBBB+ | |
2882 | * +--------------------------+ | |
2883 | * fbno fend | |
2884 | * | |
2885 | * Needs to be trimmed to: | |
2886 | * +-------+ | |
2887 | * fbno fend | |
2888 | */ | |
2889 | fbno = bend; | |
2890 | } else if (bend >= fend) { | |
2891 | /* end overlap */ | |
2892 | ||
2893 | /* | |
2894 | * Case 7: | |
2895 | * bbno bend | |
2896 | * +BBBBBBBBBBBBBBBBB+ | |
2897 | * +------------------+ | |
2898 | * fbno fend | |
2899 | * | |
2900 | * Case 8: | |
2901 | * bbno bend | |
2902 | * +BBBBBBBBBBBBBBBBB+ | |
2903 | * +--------------------------+ | |
2904 | * fbno fend | |
2905 | * | |
2906 | * Needs to be trimmed to: | |
2907 | * +-------+ | |
2908 | * fbno fend | |
2909 | */ | |
2910 | fend = bbno; | |
2911 | } else { | |
2912 | /* middle overlap */ | |
2913 | ||
2914 | /* | |
2915 | * Case 9: | |
2916 | * bbno bend | |
2917 | * +BBBBBBBBBBBBBBBBB+ | |
2918 | * +-----------------------------------+ | |
2919 | * fbno fend | |
2920 | * | |
2921 | * Can be trimmed to: | |
2922 | * +-------+ OR +-------+ | |
2923 | * fbno fend fbno fend | |
2924 | * | |
2925 | * Backward allocation leads to significant | |
2926 | * fragmentation of directories, which degrades | |
2927 | * directory performance, therefore we always want to | |
2928 | * choose the option that produces forward allocation | |
2929 | * patterns. | |
2930 | * Preferring the lower bno extent will make the next | |
2931 | * request use "fend" as the start of the next | |
2932 | * allocation; if the segment is no longer busy at | |
2933 | * that point, we'll get a contiguous allocation, but | |
2934 | * even if it is still busy, we will get a forward | |
2935 | * allocation. | |
2936 | * We try to avoid choosing the segment at "bend", | |
2937 | * because that can lead to the next allocation | |
2938 | * taking the segment at "fbno", which would be a | |
2939 | * backward allocation. We only use the segment at | |
2940 | * "fbno" if it is much larger than the current | |
2941 | * requested size, because in that case there's a | |
2942 | * good chance subsequent allocations will be | |
2943 | * contiguous. | |
2944 | */ | |
2945 | if (bbno - fbno >= args->maxlen) { | |
2946 | /* left candidate fits perfect */ | |
2947 | fend = bbno; | |
2948 | } else if (fend - bend >= args->maxlen * 4) { | |
2949 | /* right candidate has enough free space */ | |
2950 | fbno = bend; | |
2951 | } else if (bbno - fbno >= args->minlen) { | |
2952 | /* left candidate fits minimum requirement */ | |
2953 | fend = bbno; | |
2954 | } else { | |
2955 | goto fail; | |
2956 | } | |
2957 | } | |
2958 | ||
2959 | flen = fend - fbno; | |
2960 | } | |
2961 | spin_unlock(&args->pag->pagb_lock); | |
2962 | ||
2963 | if (fbno != bno || flen != len) { | |
2964 | trace_xfs_alloc_busy_trim(args->mp, args->agno, bno, len, | |
2965 | fbno, flen); | |
2966 | } | |
2967 | *rbno = fbno; | |
2968 | *rlen = flen; | |
2969 | return; | |
2970 | fail: | |
2971 | /* | |
2972 | * Return a zero extent length as failure indications. All callers | |
2973 | * re-check if the trimmed extent satisfies the minlen requirement. | |
2974 | */ | |
2975 | spin_unlock(&args->pag->pagb_lock); | |
2976 | trace_xfs_alloc_busy_trim(args->mp, args->agno, bno, len, fbno, 0); | |
2977 | *rbno = fbno; | |
2978 | *rlen = 0; | |
2979 | } | |
2980 | ||
8a072a4d CH |
2981 | static void |
2982 | xfs_alloc_busy_clear_one( | |
ed3b4d6c | 2983 | struct xfs_mount *mp, |
8a072a4d | 2984 | struct xfs_perag *pag, |
ed3b4d6c | 2985 | struct xfs_busy_extent *busyp) |
1da177e4 | 2986 | { |
97d3ac75 CH |
2987 | if (busyp->length) { |
2988 | trace_xfs_alloc_busy_clear(mp, busyp->agno, busyp->bno, | |
2989 | busyp->length); | |
2990 | rb_erase(&busyp->rb_node, &pag->pagb_tree); | |
2991 | } | |
0b1b213f | 2992 | |
8a072a4d | 2993 | list_del_init(&busyp->list); |
ed3b4d6c | 2994 | kmem_free(busyp); |
1da177e4 | 2995 | } |
8a072a4d | 2996 | |
e84661aa CH |
2997 | /* |
2998 | * Remove all extents on the passed in list from the busy extents tree. | |
2999 | * If do_discard is set skip extents that need to be discarded, and mark | |
3000 | * these as undergoing a discard operation instead. | |
3001 | */ | |
8a072a4d CH |
3002 | void |
3003 | xfs_alloc_busy_clear( | |
3004 | struct xfs_mount *mp, | |
e84661aa CH |
3005 | struct list_head *list, |
3006 | bool do_discard) | |
8a072a4d CH |
3007 | { |
3008 | struct xfs_busy_extent *busyp, *n; | |
3009 | struct xfs_perag *pag = NULL; | |
3010 | xfs_agnumber_t agno = NULLAGNUMBER; | |
3011 | ||
3012 | list_for_each_entry_safe(busyp, n, list, list) { | |
3013 | if (busyp->agno != agno) { | |
3014 | if (pag) { | |
3015 | spin_unlock(&pag->pagb_lock); | |
3016 | xfs_perag_put(pag); | |
3017 | } | |
3018 | pag = xfs_perag_get(mp, busyp->agno); | |
3019 | spin_lock(&pag->pagb_lock); | |
3020 | agno = busyp->agno; | |
3021 | } | |
3022 | ||
55a7bc5a CH |
3023 | if (do_discard && busyp->length && |
3024 | !(busyp->flags & XFS_ALLOC_BUSY_SKIP_DISCARD)) | |
e84661aa CH |
3025 | busyp->flags = XFS_ALLOC_BUSY_DISCARDED; |
3026 | else | |
3027 | xfs_alloc_busy_clear_one(mp, pag, busyp); | |
8a072a4d CH |
3028 | } |
3029 | ||
3030 | if (pag) { | |
3031 | spin_unlock(&pag->pagb_lock); | |
3032 | xfs_perag_put(pag); | |
3033 | } | |
3034 | } | |
3035 | ||
3036 | /* | |
3037 | * Callback for list_sort to sort busy extents by the AG they reside in. | |
3038 | */ | |
3039 | int | |
3040 | xfs_busy_extent_ag_cmp( | |
3041 | void *priv, | |
3042 | struct list_head *a, | |
3043 | struct list_head *b) | |
3044 | { | |
3045 | return container_of(a, struct xfs_busy_extent, list)->agno - | |
3046 | container_of(b, struct xfs_busy_extent, list)->agno; | |
3047 | } |