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15637ed4 RG |
1 | /* |
2 | * Copyright (c) 1982, 1986, 1988, 1991 Regents of the University of California. | |
3 | * All rights reserved. | |
4 | * | |
5 | * Redistribution and use in source and binary forms, with or without | |
6 | * modification, are permitted provided that the following conditions | |
7 | * are met: | |
8 | * 1. Redistributions of source code must retain the above copyright | |
9 | * notice, this list of conditions and the following disclaimer. | |
10 | * 2. Redistributions in binary form must reproduce the above copyright | |
11 | * notice, this list of conditions and the following disclaimer in the | |
12 | * documentation and/or other materials provided with the distribution. | |
13 | * 3. All advertising materials mentioning features or use of this software | |
14 | * must display the following acknowledgement: | |
15 | * This product includes software developed by the University of | |
16 | * California, Berkeley and its contributors. | |
17 | * 4. Neither the name of the University nor the names of its contributors | |
18 | * may be used to endorse or promote products derived from this software | |
19 | * without specific prior written permission. | |
20 | * | |
21 | * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND | |
22 | * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE | |
23 | * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE | |
24 | * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE | |
25 | * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL | |
26 | * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS | |
27 | * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) | |
28 | * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT | |
29 | * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY | |
30 | * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF | |
31 | * SUCH DAMAGE. | |
32 | * | |
600f7f07 RG |
33 | * from: @(#)uipc_mbuf.c 7.19 (Berkeley) 4/20/91 |
34 | * $Id$ | |
15637ed4 RG |
35 | */ |
36 | ||
37 | #include "param.h" | |
dd18dc33 | 38 | #include "systm.h" |
15637ed4 RG |
39 | #include "proc.h" |
40 | #include "malloc.h" | |
41 | #define MBTYPES | |
42 | #include "mbuf.h" | |
43 | #include "kernel.h" | |
44 | #include "syslog.h" | |
45 | #include "domain.h" | |
46 | #include "protosw.h" | |
47 | #include "vm/vm.h" | |
48 | ||
49 | extern vm_map_t mb_map; | |
50 | struct mbuf *mbutl; | |
51 | char *mclrefcnt; | |
52 | ||
53 | mbinit() | |
54 | { | |
55 | int s; | |
56 | ||
57 | #if CLBYTES < 4096 | |
58 | #define NCL_INIT (4096/CLBYTES) | |
59 | #else | |
60 | #define NCL_INIT 1 | |
61 | #endif | |
62 | s = splimp(); | |
63 | if (m_clalloc(NCL_INIT, M_DONTWAIT) == 0) | |
64 | goto bad; | |
65 | splx(s); | |
66 | return; | |
67 | bad: | |
68 | panic("mbinit"); | |
69 | } | |
70 | ||
71 | /* | |
72 | * Allocate some number of mbuf clusters | |
73 | * and place on cluster free list. | |
74 | * Must be called at splimp. | |
75 | */ | |
76 | /* ARGSUSED */ | |
77 | m_clalloc(ncl, how) /* 31 Aug 92*/ | |
78 | register int ncl; | |
79 | { | |
80 | int npg, mbx; | |
81 | register caddr_t p; | |
82 | register int i; | |
83 | static int logged; | |
84 | ||
85 | npg = ncl * CLSIZE; | |
86 | /* 31 Aug 92*/ | |
87 | p = (caddr_t)kmem_malloc(mb_map, ctob(npg), !(how&M_DONTWAIT)); | |
88 | if (p == NULL) { | |
89 | if (logged == 0) { | |
90 | logged++; | |
91 | log(LOG_ERR, "mb_map full\n"); | |
92 | } | |
93 | return (0); | |
94 | } | |
95 | ncl = ncl * CLBYTES / MCLBYTES; | |
96 | for (i = 0; i < ncl; i++) { | |
97 | ((union mcluster *)p)->mcl_next = mclfree; | |
98 | mclfree = (union mcluster *)p; | |
99 | p += MCLBYTES; | |
100 | mbstat.m_clfree++; | |
101 | } | |
102 | mbstat.m_clusters += ncl; | |
103 | return (1); | |
104 | } | |
105 | ||
106 | /* | |
107 | * When MGET failes, ask protocols to free space when short of memory, | |
108 | * then re-attempt to allocate an mbuf. | |
109 | */ | |
110 | struct mbuf * | |
111 | m_retry(i, t) | |
112 | int i, t; | |
113 | { | |
114 | register struct mbuf *m; | |
115 | ||
116 | m_reclaim(); | |
117 | #define m_retry(i, t) (struct mbuf *)0 | |
118 | MGET(m, i, t); | |
119 | #undef m_retry | |
120 | return (m); | |
121 | } | |
122 | ||
123 | /* | |
124 | * As above; retry an MGETHDR. | |
125 | */ | |
126 | struct mbuf * | |
127 | m_retryhdr(i, t) | |
128 | int i, t; | |
129 | { | |
130 | register struct mbuf *m; | |
131 | ||
132 | m_reclaim(); | |
133 | #define m_retryhdr(i, t) (struct mbuf *)0 | |
134 | MGETHDR(m, i, t); | |
135 | #undef m_retryhdr | |
136 | return (m); | |
137 | } | |
138 | ||
139 | m_reclaim() | |
140 | { | |
141 | register struct domain *dp; | |
142 | register struct protosw *pr; | |
143 | int s = splimp(); | |
144 | ||
145 | for (dp = domains; dp; dp = dp->dom_next) | |
146 | for (pr = dp->dom_protosw; pr < dp->dom_protoswNPROTOSW; pr++) | |
147 | if (pr->pr_drain) | |
148 | (*pr->pr_drain)(); | |
149 | splx(s); | |
150 | mbstat.m_drain++; | |
151 | } | |
152 | ||
153 | /* | |
154 | * Space allocation routines. | |
155 | * These are also available as macros | |
156 | * for critical paths. | |
157 | */ | |
158 | struct mbuf * | |
159 | m_get(how, type) /* 31 Aug 92*/ | |
160 | int how, type; | |
161 | { | |
162 | register struct mbuf *m; | |
163 | ||
164 | MGET(m, how, type); | |
165 | return (m); | |
166 | } | |
167 | ||
168 | struct mbuf * | |
169 | m_gethdr(how, type) /* 31 Aug 92*/ | |
170 | int how, type; | |
171 | { | |
172 | register struct mbuf *m; | |
173 | ||
174 | MGETHDR(m, how, type); | |
175 | return (m); | |
176 | } | |
177 | ||
178 | struct mbuf * | |
179 | m_getclr(how, type) /* 31 Aug 92*/ | |
180 | int how, type; | |
181 | { | |
182 | register struct mbuf *m; | |
183 | ||
184 | MGET(m, how, type); | |
185 | if (m == 0) | |
186 | return (0); | |
187 | bzero(mtod(m, caddr_t), MLEN); | |
188 | return (m); | |
189 | } | |
190 | ||
191 | struct mbuf * | |
192 | m_free(m) | |
193 | struct mbuf *m; | |
194 | { | |
195 | register struct mbuf *n; | |
196 | ||
197 | MFREE(m, n); | |
198 | return (n); | |
199 | } | |
200 | ||
201 | m_freem(m) | |
202 | register struct mbuf *m; | |
203 | { | |
204 | register struct mbuf *n; | |
205 | ||
206 | if (m == NULL) | |
207 | return; | |
208 | do { | |
209 | MFREE(m, n); | |
210 | } while (m = n); | |
211 | } | |
212 | ||
213 | /* | |
214 | * Mbuffer utility routines. | |
215 | */ | |
216 | ||
217 | /* | |
218 | * Lesser-used path for M_PREPEND: | |
219 | * allocate new mbuf to prepend to chain, | |
220 | * copy junk along. | |
221 | */ | |
222 | struct mbuf * | |
223 | m_prepend(m, len, how) | |
224 | register struct mbuf *m; | |
225 | int len, how; | |
226 | { | |
227 | struct mbuf *mn; | |
228 | ||
229 | MGET(mn, how, m->m_type); | |
230 | if (mn == (struct mbuf *)NULL) { | |
231 | m_freem(m); | |
232 | return ((struct mbuf *)NULL); | |
233 | } | |
234 | if (m->m_flags & M_PKTHDR) { | |
235 | M_COPY_PKTHDR(mn, m); | |
236 | m->m_flags &= ~M_PKTHDR; | |
237 | } | |
238 | mn->m_next = m; | |
239 | m = mn; | |
240 | if (len < MHLEN) | |
241 | MH_ALIGN(m, len); | |
242 | m->m_len = len; | |
243 | return (m); | |
244 | } | |
245 | ||
246 | /* | |
247 | * Make a copy of an mbuf chain starting "off0" bytes from the beginning, | |
248 | * continuing for "len" bytes. If len is M_COPYALL, copy to end of mbuf. | |
249 | * The wait parameter is a choice of M_WAIT/M_DONTWAIT from caller. | |
250 | */ | |
251 | int MCFail; | |
252 | ||
253 | struct mbuf * | |
254 | m_copym(m, off0, len, wait) | |
255 | register struct mbuf *m; | |
256 | int off0, wait; | |
257 | register int len; | |
258 | { | |
259 | register struct mbuf *n, **np; | |
260 | register int off = off0; | |
261 | struct mbuf *top; | |
262 | int copyhdr = 0; | |
263 | ||
264 | if (off < 0 || len < 0) | |
265 | panic("m_copym"); | |
266 | if (off == 0 && m->m_flags & M_PKTHDR) | |
267 | copyhdr = 1; | |
268 | while (off > 0) { | |
269 | if (m == 0) | |
270 | panic("m_copym"); | |
271 | if (off < m->m_len) | |
272 | break; | |
273 | off -= m->m_len; | |
274 | m = m->m_next; | |
275 | } | |
276 | np = ⊤ | |
277 | top = 0; | |
278 | while (len > 0) { | |
279 | if (m == 0) { | |
280 | if (len != M_COPYALL) | |
281 | panic("m_copym"); | |
282 | break; | |
283 | } | |
284 | MGET(n, wait, m->m_type); | |
285 | *np = n; | |
286 | if (n == 0) | |
287 | goto nospace; | |
288 | if (copyhdr) { | |
289 | M_COPY_PKTHDR(n, m); | |
290 | if (len == M_COPYALL) | |
291 | n->m_pkthdr.len -= off0; | |
292 | else | |
293 | n->m_pkthdr.len = len; | |
294 | copyhdr = 0; | |
295 | } | |
296 | n->m_len = MIN(len, m->m_len - off); | |
297 | if (m->m_flags & M_EXT) { | |
298 | n->m_data = m->m_data + off; | |
299 | mclrefcnt[mtocl(m->m_ext.ext_buf)]++; | |
300 | n->m_ext = m->m_ext; | |
301 | n->m_flags |= M_EXT; | |
302 | } else | |
303 | bcopy(mtod(m, caddr_t)+off, mtod(n, caddr_t), | |
304 | (unsigned)n->m_len); | |
305 | if (len != M_COPYALL) | |
306 | len -= n->m_len; | |
307 | off = 0; | |
308 | m = m->m_next; | |
309 | np = &n->m_next; | |
310 | } | |
311 | if (top == 0) | |
312 | MCFail++; | |
313 | return (top); | |
314 | nospace: | |
315 | m_freem(top); | |
316 | MCFail++; | |
317 | return (0); | |
318 | } | |
319 | ||
320 | /* | |
321 | * Copy data from an mbuf chain starting "off" bytes from the beginning, | |
322 | * continuing for "len" bytes, into the indicated buffer. | |
323 | */ | |
324 | m_copydata(m, off, len, cp) | |
325 | register struct mbuf *m; | |
326 | register int off; | |
327 | register int len; | |
328 | caddr_t cp; | |
329 | { | |
330 | register unsigned count; | |
331 | ||
332 | if (off < 0 || len < 0) | |
333 | panic("m_copydata"); | |
334 | while (off > 0) { | |
335 | if (m == 0) | |
336 | panic("m_copydata"); | |
337 | if (off < m->m_len) | |
338 | break; | |
339 | off -= m->m_len; | |
340 | m = m->m_next; | |
341 | } | |
342 | while (len > 0) { | |
343 | if (m == 0) | |
344 | panic("m_copydata"); | |
345 | count = MIN(m->m_len - off, len); | |
346 | bcopy(mtod(m, caddr_t) + off, cp, count); | |
347 | len -= count; | |
348 | cp += count; | |
349 | off = 0; | |
350 | m = m->m_next; | |
351 | } | |
352 | } | |
353 | ||
354 | /* | |
355 | * Concatenate mbuf chain n to m. | |
356 | * Both chains must be of the same type (e.g. MT_DATA). | |
357 | * Any m_pkthdr is not updated. | |
358 | */ | |
359 | m_cat(m, n) | |
360 | register struct mbuf *m, *n; | |
361 | { | |
362 | while (m->m_next) | |
363 | m = m->m_next; | |
364 | while (n) { | |
365 | if (m->m_flags & M_EXT || | |
366 | m->m_data + m->m_len + n->m_len >= &m->m_dat[MLEN]) { | |
367 | /* just join the two chains */ | |
368 | m->m_next = n; | |
369 | return; | |
370 | } | |
371 | /* splat the data from one into the other */ | |
372 | bcopy(mtod(n, caddr_t), mtod(m, caddr_t) + m->m_len, | |
373 | (u_int)n->m_len); | |
374 | m->m_len += n->m_len; | |
375 | n = m_free(n); | |
376 | } | |
377 | } | |
378 | ||
379 | m_adj(mp, req_len) | |
380 | struct mbuf *mp; | |
381 | { | |
382 | register int len = req_len; | |
383 | register struct mbuf *m; | |
384 | register count; | |
385 | ||
386 | if ((m = mp) == NULL) | |
387 | return; | |
388 | if (len >= 0) { | |
389 | /* | |
390 | * Trim from head. | |
391 | */ | |
392 | while (m != NULL && len > 0) { | |
393 | if (m->m_len <= len) { | |
394 | len -= m->m_len; | |
395 | m->m_len = 0; | |
396 | m = m->m_next; | |
397 | } else { | |
398 | m->m_len -= len; | |
399 | m->m_data += len; | |
400 | len = 0; | |
401 | } | |
402 | } | |
403 | m = mp; | |
404 | if (mp->m_flags & M_PKTHDR) | |
405 | m->m_pkthdr.len -= (req_len - len); | |
406 | } else { | |
407 | /* | |
408 | * Trim from tail. Scan the mbuf chain, | |
409 | * calculating its length and finding the last mbuf. | |
410 | * If the adjustment only affects this mbuf, then just | |
411 | * adjust and return. Otherwise, rescan and truncate | |
412 | * after the remaining size. | |
413 | */ | |
414 | len = -len; | |
415 | count = 0; | |
416 | for (;;) { | |
417 | count += m->m_len; | |
418 | if (m->m_next == (struct mbuf *)0) | |
419 | break; | |
420 | m = m->m_next; | |
421 | } | |
422 | if (m->m_len >= len) { | |
423 | m->m_len -= len; | |
424 | if ((mp = m)->m_flags & M_PKTHDR) | |
425 | m->m_pkthdr.len -= len; | |
426 | return; | |
427 | } | |
428 | count -= len; | |
429 | if (count < 0) | |
430 | count = 0; | |
431 | /* | |
432 | * Correct length for chain is "count". | |
433 | * Find the mbuf with last data, adjust its length, | |
434 | * and toss data from remaining mbufs on chain. | |
435 | */ | |
436 | m = mp; | |
437 | if (m->m_flags & M_PKTHDR) | |
438 | m->m_pkthdr.len = count; | |
439 | for (; m; m = m->m_next) { | |
440 | if (m->m_len >= count) { | |
441 | m->m_len = count; | |
442 | break; | |
443 | } | |
444 | count -= m->m_len; | |
445 | } | |
446 | while (m = m->m_next) | |
447 | m->m_len = 0; | |
448 | } | |
449 | } | |
450 | ||
451 | /* | |
452 | * Rearange an mbuf chain so that len bytes are contiguous | |
453 | * and in the data area of an mbuf (so that mtod and dtom | |
454 | * will work for a structure of size len). Returns the resulting | |
455 | * mbuf chain on success, frees it and returns null on failure. | |
456 | * If there is room, it will add up to max_protohdr-len extra bytes to the | |
457 | * contiguous region in an attempt to avoid being called next time. | |
458 | */ | |
459 | int MPFail; | |
460 | ||
461 | struct mbuf * | |
462 | m_pullup(n, len) | |
463 | register struct mbuf *n; | |
464 | int len; | |
465 | { | |
466 | register struct mbuf *m; | |
467 | register int count; | |
468 | int space; | |
469 | ||
470 | /* | |
471 | * If first mbuf has no cluster, and has room for len bytes | |
472 | * without shifting current data, pullup into it, | |
473 | * otherwise allocate a new mbuf to prepend to the chain. | |
474 | */ | |
475 | if ((n->m_flags & M_EXT) == 0 && | |
476 | n->m_data + len < &n->m_dat[MLEN] && n->m_next) { | |
477 | if (n->m_len >= len) | |
478 | return (n); | |
479 | m = n; | |
480 | n = n->m_next; | |
481 | len -= m->m_len; | |
482 | } else { | |
483 | if (len > MHLEN) | |
484 | goto bad; | |
485 | MGET(m, M_DONTWAIT, n->m_type); | |
486 | if (m == 0) | |
487 | goto bad; | |
488 | m->m_len = 0; | |
489 | if (n->m_flags & M_PKTHDR) { | |
490 | M_COPY_PKTHDR(m, n); | |
491 | n->m_flags &= ~M_PKTHDR; | |
492 | } | |
493 | } | |
494 | space = &m->m_dat[MLEN] - (m->m_data + m->m_len); | |
495 | do { | |
496 | count = min(min(max(len, max_protohdr), space), n->m_len); | |
497 | bcopy(mtod(n, caddr_t), mtod(m, caddr_t) + m->m_len, | |
498 | (unsigned)count); | |
499 | len -= count; | |
500 | m->m_len += count; | |
501 | n->m_len -= count; | |
502 | space -= count; | |
503 | if (n->m_len) | |
504 | n->m_data += count; | |
505 | else | |
506 | n = m_free(n); | |
507 | } while (len > 0 && n); | |
508 | if (len > 0) { | |
509 | (void) m_free(m); | |
510 | goto bad; | |
511 | } | |
512 | m->m_next = n; | |
513 | return (m); | |
514 | bad: | |
515 | m_freem(n); | |
516 | MPFail++; | |
517 | return (0); | |
518 | } |