diff options
author | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 18:20:36 -0400 |
---|---|---|
committer | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 18:20:36 -0400 |
commit | 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch) | |
tree | 0bba044c4ce775e45a88a51686b5d9f90697ea9d /fs/hpfs/alloc.c |
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
Diffstat (limited to 'fs/hpfs/alloc.c')
-rw-r--r-- | fs/hpfs/alloc.c | 456 |
1 files changed, 456 insertions, 0 deletions
diff --git a/fs/hpfs/alloc.c b/fs/hpfs/alloc.c new file mode 100644 index 000000000000..5503e2c28910 --- /dev/null +++ b/fs/hpfs/alloc.c | |||
@@ -0,0 +1,456 @@ | |||
1 | /* | ||
2 | * linux/fs/hpfs/alloc.c | ||
3 | * | ||
4 | * Mikulas Patocka (mikulas@artax.karlin.mff.cuni.cz), 1998-1999 | ||
5 | * | ||
6 | * HPFS bitmap operations | ||
7 | */ | ||
8 | |||
9 | #include "hpfs_fn.h" | ||
10 | |||
11 | static int hpfs_alloc_if_possible_nolock(struct super_block *s, secno sec); | ||
12 | |||
13 | /* | ||
14 | * Check if a sector is allocated in bitmap | ||
15 | * This is really slow. Turned on only if chk==2 | ||
16 | */ | ||
17 | |||
18 | static int chk_if_allocated(struct super_block *s, secno sec, char *msg) | ||
19 | { | ||
20 | struct quad_buffer_head qbh; | ||
21 | unsigned *bmp; | ||
22 | if (!(bmp = hpfs_map_bitmap(s, sec >> 14, &qbh, "chk"))) goto fail; | ||
23 | if ((bmp[(sec & 0x3fff) >> 5] >> (sec & 0x1f)) & 1) { | ||
24 | hpfs_error(s, "sector '%s' - %08x not allocated in bitmap", msg, sec); | ||
25 | goto fail1; | ||
26 | } | ||
27 | hpfs_brelse4(&qbh); | ||
28 | if (sec >= hpfs_sb(s)->sb_dirband_start && sec < hpfs_sb(s)->sb_dirband_start + hpfs_sb(s)->sb_dirband_size) { | ||
29 | unsigned ssec = (sec - hpfs_sb(s)->sb_dirband_start) / 4; | ||
30 | if (!(bmp = hpfs_map_dnode_bitmap(s, &qbh))) goto fail; | ||
31 | if ((bmp[ssec >> 5] >> (ssec & 0x1f)) & 1) { | ||
32 | hpfs_error(s, "sector '%s' - %08x not allocated in directory bitmap", msg, sec); | ||
33 | goto fail1; | ||
34 | } | ||
35 | hpfs_brelse4(&qbh); | ||
36 | } | ||
37 | return 0; | ||
38 | fail1: | ||
39 | hpfs_brelse4(&qbh); | ||
40 | fail: | ||
41 | return 1; | ||
42 | } | ||
43 | |||
44 | /* | ||
45 | * Check if sector(s) have proper number and additionally check if they're | ||
46 | * allocated in bitmap. | ||
47 | */ | ||
48 | |||
49 | int hpfs_chk_sectors(struct super_block *s, secno start, int len, char *msg) | ||
50 | { | ||
51 | if (start + len < start || start < 0x12 || | ||
52 | start + len > hpfs_sb(s)->sb_fs_size) { | ||
53 | hpfs_error(s, "sector(s) '%s' badly placed at %08x", msg, start); | ||
54 | return 1; | ||
55 | } | ||
56 | if (hpfs_sb(s)->sb_chk>=2) { | ||
57 | int i; | ||
58 | for (i = 0; i < len; i++) | ||
59 | if (chk_if_allocated(s, start + i, msg)) return 1; | ||
60 | } | ||
61 | return 0; | ||
62 | } | ||
63 | |||
64 | static secno alloc_in_bmp(struct super_block *s, secno near, unsigned n, unsigned forward) | ||
65 | { | ||
66 | struct quad_buffer_head qbh; | ||
67 | unsigned *bmp; | ||
68 | unsigned bs = near & ~0x3fff; | ||
69 | unsigned nr = (near & 0x3fff) & ~(n - 1); | ||
70 | /*unsigned mnr;*/ | ||
71 | unsigned i, q; | ||
72 | int a, b; | ||
73 | secno ret = 0; | ||
74 | if (n != 1 && n != 4) { | ||
75 | hpfs_error(s, "Bad allocation size: %d", n); | ||
76 | return 0; | ||
77 | } | ||
78 | lock_super(s); | ||
79 | if (bs != ~0x3fff) { | ||
80 | if (!(bmp = hpfs_map_bitmap(s, near >> 14, &qbh, "aib"))) goto uls; | ||
81 | } else { | ||
82 | if (!(bmp = hpfs_map_dnode_bitmap(s, &qbh))) goto uls; | ||
83 | } | ||
84 | if (!tstbits(bmp, nr, n + forward)) { | ||
85 | ret = bs + nr; | ||
86 | goto rt; | ||
87 | } | ||
88 | /*if (!tstbits(bmp, nr + n, n + forward)) { | ||
89 | ret = bs + nr + n; | ||
90 | goto rt; | ||
91 | }*/ | ||
92 | q = nr + n; b = 0; | ||
93 | while ((a = tstbits(bmp, q, n + forward)) != 0) { | ||
94 | q += a; | ||
95 | if (n != 1) q = ((q-1)&~(n-1))+n; | ||
96 | if (!b) { | ||
97 | if (q>>5 != nr>>5) { | ||
98 | b = 1; | ||
99 | q = nr & 0x1f; | ||
100 | } | ||
101 | } else if (q > nr) break; | ||
102 | } | ||
103 | if (!a) { | ||
104 | ret = bs + q; | ||
105 | goto rt; | ||
106 | } | ||
107 | nr >>= 5; | ||
108 | /*for (i = nr + 1; i != nr; i++, i &= 0x1ff) {*/ | ||
109 | i = nr; | ||
110 | do { | ||
111 | if (!bmp[i]) goto cont; | ||
112 | if (n + forward >= 0x3f && bmp[i] != -1) goto cont; | ||
113 | q = i<<5; | ||
114 | if (i > 0) { | ||
115 | unsigned k = bmp[i-1]; | ||
116 | while (k & 0x80000000) { | ||
117 | q--; k <<= 1; | ||
118 | } | ||
119 | } | ||
120 | if (n != 1) q = ((q-1)&~(n-1))+n; | ||
121 | while ((a = tstbits(bmp, q, n + forward)) != 0) { | ||
122 | q += a; | ||
123 | if (n != 1) q = ((q-1)&~(n-1))+n; | ||
124 | if (q>>5 > i) break; | ||
125 | } | ||
126 | if (!a) { | ||
127 | ret = bs + q; | ||
128 | goto rt; | ||
129 | } | ||
130 | cont: | ||
131 | i++, i &= 0x1ff; | ||
132 | } while (i != nr); | ||
133 | rt: | ||
134 | if (ret) { | ||
135 | if (hpfs_sb(s)->sb_chk && ((ret >> 14) != (bs >> 14) || (bmp[(ret & 0x3fff) >> 5] | ~(((1 << n) - 1) << (ret & 0x1f))) != 0xffffffff)) { | ||
136 | hpfs_error(s, "Allocation doesn't work! Wanted %d, allocated at %08x", n, ret); | ||
137 | ret = 0; | ||
138 | goto b; | ||
139 | } | ||
140 | bmp[(ret & 0x3fff) >> 5] &= ~(((1 << n) - 1) << (ret & 0x1f)); | ||
141 | hpfs_mark_4buffers_dirty(&qbh); | ||
142 | } | ||
143 | b: | ||
144 | hpfs_brelse4(&qbh); | ||
145 | uls: | ||
146 | unlock_super(s); | ||
147 | return ret; | ||
148 | } | ||
149 | |||
150 | /* | ||
151 | * Allocation strategy: 1) search place near the sector specified | ||
152 | * 2) search bitmap where free sectors last found | ||
153 | * 3) search all bitmaps | ||
154 | * 4) search all bitmaps ignoring number of pre-allocated | ||
155 | * sectors | ||
156 | */ | ||
157 | |||
158 | secno hpfs_alloc_sector(struct super_block *s, secno near, unsigned n, int forward, int lock) | ||
159 | { | ||
160 | secno sec; | ||
161 | int i; | ||
162 | unsigned n_bmps; | ||
163 | struct hpfs_sb_info *sbi = hpfs_sb(s); | ||
164 | int f_p = 0; | ||
165 | int near_bmp; | ||
166 | if (forward < 0) { | ||
167 | forward = -forward; | ||
168 | f_p = 1; | ||
169 | } | ||
170 | if (lock) hpfs_lock_creation(s); | ||
171 | n_bmps = (sbi->sb_fs_size + 0x4000 - 1) >> 14; | ||
172 | if (near && near < sbi->sb_fs_size) { | ||
173 | if ((sec = alloc_in_bmp(s, near, n, f_p ? forward : forward/4))) goto ret; | ||
174 | near_bmp = near >> 14; | ||
175 | } else near_bmp = n_bmps / 2; | ||
176 | /* | ||
177 | if (b != -1) { | ||
178 | if ((sec = alloc_in_bmp(s, b<<14, n, f_p ? forward : forward/2))) { | ||
179 | b &= 0x0fffffff; | ||
180 | goto ret; | ||
181 | } | ||
182 | if (b > 0x10000000) if ((sec = alloc_in_bmp(s, (b&0xfffffff)<<14, n, f_p ? forward : 0))) goto ret; | ||
183 | */ | ||
184 | if (!f_p) if (forward > sbi->sb_max_fwd_alloc) forward = sbi->sb_max_fwd_alloc; | ||
185 | less_fwd: | ||
186 | for (i = 0; i < n_bmps; i++) { | ||
187 | if (near_bmp+i < n_bmps && ((sec = alloc_in_bmp(s, (near_bmp+i) << 14, n, forward)))) { | ||
188 | sbi->sb_c_bitmap = near_bmp+i; | ||
189 | goto ret; | ||
190 | } | ||
191 | if (!forward) { | ||
192 | if (near_bmp-i-1 >= 0 && ((sec = alloc_in_bmp(s, (near_bmp-i-1) << 14, n, forward)))) { | ||
193 | sbi->sb_c_bitmap = near_bmp-i-1; | ||
194 | goto ret; | ||
195 | } | ||
196 | } else { | ||
197 | if (near_bmp+i >= n_bmps && ((sec = alloc_in_bmp(s, (near_bmp+i-n_bmps) << 14, n, forward)))) { | ||
198 | sbi->sb_c_bitmap = near_bmp+i-n_bmps; | ||
199 | goto ret; | ||
200 | } | ||
201 | } | ||
202 | if (i == 1 && sbi->sb_c_bitmap != -1 && ((sec = alloc_in_bmp(s, (sbi->sb_c_bitmap) << 14, n, forward)))) { | ||
203 | goto ret; | ||
204 | } | ||
205 | } | ||
206 | if (!f_p) { | ||
207 | if (forward) { | ||
208 | sbi->sb_max_fwd_alloc = forward * 3 / 4; | ||
209 | forward /= 2; | ||
210 | goto less_fwd; | ||
211 | } | ||
212 | } | ||
213 | sec = 0; | ||
214 | ret: | ||
215 | if (sec && f_p) { | ||
216 | for (i = 0; i < forward; i++) { | ||
217 | if (!hpfs_alloc_if_possible_nolock(s, sec + i + 1)) { | ||
218 | hpfs_error(s, "Prealloc doesn't work! Wanted %d, allocated at %08x, can't allocate %d", forward, sec, i); | ||
219 | sec = 0; | ||
220 | break; | ||
221 | } | ||
222 | } | ||
223 | } | ||
224 | if (lock) hpfs_unlock_creation(s); | ||
225 | return sec; | ||
226 | } | ||
227 | |||
228 | static secno alloc_in_dirband(struct super_block *s, secno near, int lock) | ||
229 | { | ||
230 | unsigned nr = near; | ||
231 | secno sec; | ||
232 | struct hpfs_sb_info *sbi = hpfs_sb(s); | ||
233 | if (nr < sbi->sb_dirband_start) | ||
234 | nr = sbi->sb_dirband_start; | ||
235 | if (nr >= sbi->sb_dirband_start + sbi->sb_dirband_size) | ||
236 | nr = sbi->sb_dirband_start + sbi->sb_dirband_size - 4; | ||
237 | nr -= sbi->sb_dirband_start; | ||
238 | nr >>= 2; | ||
239 | if (lock) hpfs_lock_creation(s); | ||
240 | sec = alloc_in_bmp(s, (~0x3fff) | nr, 1, 0); | ||
241 | if (lock) hpfs_unlock_creation(s); | ||
242 | if (!sec) return 0; | ||
243 | return ((sec & 0x3fff) << 2) + sbi->sb_dirband_start; | ||
244 | } | ||
245 | |||
246 | /* Alloc sector if it's free */ | ||
247 | |||
248 | static int hpfs_alloc_if_possible_nolock(struct super_block *s, secno sec) | ||
249 | { | ||
250 | struct quad_buffer_head qbh; | ||
251 | unsigned *bmp; | ||
252 | lock_super(s); | ||
253 | if (!(bmp = hpfs_map_bitmap(s, sec >> 14, &qbh, "aip"))) goto end; | ||
254 | if (bmp[(sec & 0x3fff) >> 5] & (1 << (sec & 0x1f))) { | ||
255 | bmp[(sec & 0x3fff) >> 5] &= ~(1 << (sec & 0x1f)); | ||
256 | hpfs_mark_4buffers_dirty(&qbh); | ||
257 | hpfs_brelse4(&qbh); | ||
258 | unlock_super(s); | ||
259 | return 1; | ||
260 | } | ||
261 | hpfs_brelse4(&qbh); | ||
262 | end: | ||
263 | unlock_super(s); | ||
264 | return 0; | ||
265 | } | ||
266 | |||
267 | int hpfs_alloc_if_possible(struct super_block *s, secno sec) | ||
268 | { | ||
269 | int r; | ||
270 | hpfs_lock_creation(s); | ||
271 | r = hpfs_alloc_if_possible_nolock(s, sec); | ||
272 | hpfs_unlock_creation(s); | ||
273 | return r; | ||
274 | } | ||
275 | |||
276 | /* Free sectors in bitmaps */ | ||
277 | |||
278 | void hpfs_free_sectors(struct super_block *s, secno sec, unsigned n) | ||
279 | { | ||
280 | struct quad_buffer_head qbh; | ||
281 | unsigned *bmp; | ||
282 | struct hpfs_sb_info *sbi = hpfs_sb(s); | ||
283 | /*printk("2 - ");*/ | ||
284 | if (!n) return; | ||
285 | if (sec < 0x12) { | ||
286 | hpfs_error(s, "Trying to free reserved sector %08x", sec); | ||
287 | return; | ||
288 | } | ||
289 | lock_super(s); | ||
290 | sbi->sb_max_fwd_alloc += n > 0xffff ? 0xffff : n; | ||
291 | if (sbi->sb_max_fwd_alloc > 0xffffff) sbi->sb_max_fwd_alloc = 0xffffff; | ||
292 | new_map: | ||
293 | if (!(bmp = hpfs_map_bitmap(s, sec >> 14, &qbh, "free"))) { | ||
294 | unlock_super(s); | ||
295 | return; | ||
296 | } | ||
297 | new_tst: | ||
298 | if ((bmp[(sec & 0x3fff) >> 5] >> (sec & 0x1f) & 1)) { | ||
299 | hpfs_error(s, "sector %08x not allocated", sec); | ||
300 | hpfs_brelse4(&qbh); | ||
301 | unlock_super(s); | ||
302 | return; | ||
303 | } | ||
304 | bmp[(sec & 0x3fff) >> 5] |= 1 << (sec & 0x1f); | ||
305 | if (!--n) { | ||
306 | hpfs_mark_4buffers_dirty(&qbh); | ||
307 | hpfs_brelse4(&qbh); | ||
308 | unlock_super(s); | ||
309 | return; | ||
310 | } | ||
311 | if (!(++sec & 0x3fff)) { | ||
312 | hpfs_mark_4buffers_dirty(&qbh); | ||
313 | hpfs_brelse4(&qbh); | ||
314 | goto new_map; | ||
315 | } | ||
316 | goto new_tst; | ||
317 | } | ||
318 | |||
319 | /* | ||
320 | * Check if there are at least n free dnodes on the filesystem. | ||
321 | * Called before adding to dnode. If we run out of space while | ||
322 | * splitting dnodes, it would corrupt dnode tree. | ||
323 | */ | ||
324 | |||
325 | int hpfs_check_free_dnodes(struct super_block *s, int n) | ||
326 | { | ||
327 | int n_bmps = (hpfs_sb(s)->sb_fs_size + 0x4000 - 1) >> 14; | ||
328 | int b = hpfs_sb(s)->sb_c_bitmap & 0x0fffffff; | ||
329 | int i, j; | ||
330 | unsigned *bmp; | ||
331 | struct quad_buffer_head qbh; | ||
332 | if ((bmp = hpfs_map_dnode_bitmap(s, &qbh))) { | ||
333 | for (j = 0; j < 512; j++) { | ||
334 | unsigned k; | ||
335 | if (!bmp[j]) continue; | ||
336 | for (k = bmp[j]; k; k >>= 1) if (k & 1) if (!--n) { | ||
337 | hpfs_brelse4(&qbh); | ||
338 | return 0; | ||
339 | } | ||
340 | } | ||
341 | } | ||
342 | hpfs_brelse4(&qbh); | ||
343 | i = 0; | ||
344 | if (hpfs_sb(s)->sb_c_bitmap != -1) { | ||
345 | bmp = hpfs_map_bitmap(s, b, &qbh, "chkdn1"); | ||
346 | goto chk_bmp; | ||
347 | } | ||
348 | chk_next: | ||
349 | if (i == b) i++; | ||
350 | if (i >= n_bmps) return 1; | ||
351 | bmp = hpfs_map_bitmap(s, i, &qbh, "chkdn2"); | ||
352 | chk_bmp: | ||
353 | if (bmp) { | ||
354 | for (j = 0; j < 512; j++) { | ||
355 | unsigned k; | ||
356 | if (!bmp[j]) continue; | ||
357 | for (k = 0xf; k; k <<= 4) | ||
358 | if ((bmp[j] & k) == k) { | ||
359 | if (!--n) { | ||
360 | hpfs_brelse4(&qbh); | ||
361 | return 0; | ||
362 | } | ||
363 | } | ||
364 | } | ||
365 | hpfs_brelse4(&qbh); | ||
366 | } | ||
367 | i++; | ||
368 | goto chk_next; | ||
369 | } | ||
370 | |||
371 | void hpfs_free_dnode(struct super_block *s, dnode_secno dno) | ||
372 | { | ||
373 | if (hpfs_sb(s)->sb_chk) if (dno & 3) { | ||
374 | hpfs_error(s, "hpfs_free_dnode: dnode %08x not aligned", dno); | ||
375 | return; | ||
376 | } | ||
377 | if (dno < hpfs_sb(s)->sb_dirband_start || | ||
378 | dno >= hpfs_sb(s)->sb_dirband_start + hpfs_sb(s)->sb_dirband_size) { | ||
379 | hpfs_free_sectors(s, dno, 4); | ||
380 | } else { | ||
381 | struct quad_buffer_head qbh; | ||
382 | unsigned *bmp; | ||
383 | unsigned ssec = (dno - hpfs_sb(s)->sb_dirband_start) / 4; | ||
384 | lock_super(s); | ||
385 | if (!(bmp = hpfs_map_dnode_bitmap(s, &qbh))) { | ||
386 | unlock_super(s); | ||
387 | return; | ||
388 | } | ||
389 | bmp[ssec >> 5] |= 1 << (ssec & 0x1f); | ||
390 | hpfs_mark_4buffers_dirty(&qbh); | ||
391 | hpfs_brelse4(&qbh); | ||
392 | unlock_super(s); | ||
393 | } | ||
394 | } | ||
395 | |||
396 | struct dnode *hpfs_alloc_dnode(struct super_block *s, secno near, | ||
397 | dnode_secno *dno, struct quad_buffer_head *qbh, | ||
398 | int lock) | ||
399 | { | ||
400 | struct dnode *d; | ||
401 | if (hpfs_count_one_bitmap(s, hpfs_sb(s)->sb_dmap) > FREE_DNODES_ADD) { | ||
402 | if (!(*dno = alloc_in_dirband(s, near, lock))) | ||
403 | if (!(*dno = hpfs_alloc_sector(s, near, 4, 0, lock))) return NULL; | ||
404 | } else { | ||
405 | if (!(*dno = hpfs_alloc_sector(s, near, 4, 0, lock))) | ||
406 | if (!(*dno = alloc_in_dirband(s, near, lock))) return NULL; | ||
407 | } | ||
408 | if (!(d = hpfs_get_4sectors(s, *dno, qbh))) { | ||
409 | hpfs_free_dnode(s, *dno); | ||
410 | return NULL; | ||
411 | } | ||
412 | memset(d, 0, 2048); | ||
413 | d->magic = DNODE_MAGIC; | ||
414 | d->first_free = 52; | ||
415 | d->dirent[0] = 32; | ||
416 | d->dirent[2] = 8; | ||
417 | d->dirent[30] = 1; | ||
418 | d->dirent[31] = 255; | ||
419 | d->self = *dno; | ||
420 | return d; | ||
421 | } | ||
422 | |||
423 | struct fnode *hpfs_alloc_fnode(struct super_block *s, secno near, fnode_secno *fno, | ||
424 | struct buffer_head **bh) | ||
425 | { | ||
426 | struct fnode *f; | ||
427 | if (!(*fno = hpfs_alloc_sector(s, near, 1, FNODE_ALLOC_FWD, 1))) return NULL; | ||
428 | if (!(f = hpfs_get_sector(s, *fno, bh))) { | ||
429 | hpfs_free_sectors(s, *fno, 1); | ||
430 | return NULL; | ||
431 | } | ||
432 | memset(f, 0, 512); | ||
433 | f->magic = FNODE_MAGIC; | ||
434 | f->ea_offs = 0xc4; | ||
435 | f->btree.n_free_nodes = 8; | ||
436 | f->btree.first_free = 8; | ||
437 | return f; | ||
438 | } | ||
439 | |||
440 | struct anode *hpfs_alloc_anode(struct super_block *s, secno near, anode_secno *ano, | ||
441 | struct buffer_head **bh) | ||
442 | { | ||
443 | struct anode *a; | ||
444 | if (!(*ano = hpfs_alloc_sector(s, near, 1, ANODE_ALLOC_FWD, 1))) return NULL; | ||
445 | if (!(a = hpfs_get_sector(s, *ano, bh))) { | ||
446 | hpfs_free_sectors(s, *ano, 1); | ||
447 | return NULL; | ||
448 | } | ||
449 | memset(a, 0, 512); | ||
450 | a->magic = ANODE_MAGIC; | ||
451 | a->self = *ano; | ||
452 | a->btree.n_free_nodes = 40; | ||
453 | a->btree.n_used_nodes = 0; | ||
454 | a->btree.first_free = 8; | ||
455 | return a; | ||
456 | } | ||