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bellardf0cbd3e2004-04-22 00:10:48 +00001/*
2 * Copyright (c) 1995 Danny Gasparovski
3 *
4 * Please read the file COPYRIGHT for the
5 * terms and conditions of the copyright.
6 */
7
8/*
9 * mbuf's in SLiRP are much simpler than the real mbufs in
10 * FreeBSD. They are fixed size, determined by the MTU,
11 * so that one whole packet can fit. Mbuf's cannot be
12 * chained together. If there's more data than the mbuf
Peter Maydell70f2e642017-02-04 23:08:34 +000013 * could hold, an external g_malloced buffer is pointed to
bellardf0cbd3e2004-04-22 00:10:48 +000014 * by m_ext (and the data pointers) and M_EXT is set in
15 * the flags
16 */
17
Peter Maydell7df74822016-01-29 17:49:59 +000018#include "qemu/osdep.h"
Markus Armbrustera9c94272016-06-22 19:11:19 +020019#include "slirp.h"
bellardf0cbd3e2004-04-22 00:10:48 +000020
blueswir19634d902007-10-26 19:01:16 +000021#define MBUF_THRESH 30
blueswir19634d902007-10-26 19:01:16 +000022
23/*
24 * Find a nice value for msize
blueswir19634d902007-10-26 19:01:16 +000025 */
Guillaume Subiron98c63052016-03-15 10:31:20 +010026#define SLIRP_MSIZE\
27 (offsetof(struct mbuf, m_dat) + IF_MAXLINKHDR + TCPIPHDR_DELTA + IF_MTU)
bellardf0cbd3e2004-04-22 00:10:48 +000028
29void
Jan Kiszka460fec62009-06-24 14:42:31 +020030m_init(Slirp *slirp)
bellardf0cbd3e2004-04-22 00:10:48 +000031{
Samuel Thibault67e3eee2016-02-22 22:29:21 +010032 slirp->m_freelist.qh_link = slirp->m_freelist.qh_rlink = &slirp->m_freelist;
33 slirp->m_usedlist.qh_link = slirp->m_usedlist.qh_rlink = &slirp->m_usedlist;
bellardf0cbd3e2004-04-22 00:10:48 +000034}
35
Jan Kiszkaa68adc22012-02-29 19:14:23 +010036void m_cleanup(Slirp *slirp)
37{
38 struct mbuf *m, *next;
39
Samuel Thibault67e3eee2016-02-22 22:29:21 +010040 m = (struct mbuf *) slirp->m_usedlist.qh_link;
41 while ((struct quehead *) m != &slirp->m_usedlist) {
Jan Kiszkaa68adc22012-02-29 19:14:23 +010042 next = m->m_next;
43 if (m->m_flags & M_EXT) {
Peter Maydell70f2e642017-02-04 23:08:34 +000044 g_free(m->m_ext);
Jan Kiszkaa68adc22012-02-29 19:14:23 +010045 }
Peter Maydell70f2e642017-02-04 23:08:34 +000046 g_free(m);
Jan Kiszkaa68adc22012-02-29 19:14:23 +010047 m = next;
48 }
Samuel Thibault67e3eee2016-02-22 22:29:21 +010049 m = (struct mbuf *) slirp->m_freelist.qh_link;
50 while ((struct quehead *) m != &slirp->m_freelist) {
Jan Kiszkaa68adc22012-02-29 19:14:23 +010051 next = m->m_next;
Peter Maydell70f2e642017-02-04 23:08:34 +000052 g_free(m);
Jan Kiszkaa68adc22012-02-29 19:14:23 +010053 m = next;
54 }
55}
56
bellardf0cbd3e2004-04-22 00:10:48 +000057/*
58 * Get an mbuf from the free list, if there are none
Peter Maydell70f2e642017-02-04 23:08:34 +000059 * allocate one
ths5fafdf22007-09-16 21:08:06 +000060 *
bellardf0cbd3e2004-04-22 00:10:48 +000061 * Because fragmentation can occur if we alloc new mbufs and
62 * free old mbufs, we mark all mbufs above mbuf_thresh as M_DOFREE,
Peter Maydell70f2e642017-02-04 23:08:34 +000063 * which tells m_free to actually g_free() it
bellardf0cbd3e2004-04-22 00:10:48 +000064 */
65struct mbuf *
Jan Kiszka460fec62009-06-24 14:42:31 +020066m_get(Slirp *slirp)
bellardf0cbd3e2004-04-22 00:10:48 +000067{
68 register struct mbuf *m;
69 int flags = 0;
ths5fafdf22007-09-16 21:08:06 +000070
bellardf0cbd3e2004-04-22 00:10:48 +000071 DEBUG_CALL("m_get");
ths5fafdf22007-09-16 21:08:06 +000072
Samuel Thibault67e3eee2016-02-22 22:29:21 +010073 if (slirp->m_freelist.qh_link == &slirp->m_freelist) {
Peter Maydell70f2e642017-02-04 23:08:34 +000074 m = g_malloc(SLIRP_MSIZE);
Jan Kiszka460fec62009-06-24 14:42:31 +020075 slirp->mbuf_alloced++;
76 if (slirp->mbuf_alloced > MBUF_THRESH)
bellardf0cbd3e2004-04-22 00:10:48 +000077 flags = M_DOFREE;
Jan Kiszka460fec62009-06-24 14:42:31 +020078 m->slirp = slirp;
bellardf0cbd3e2004-04-22 00:10:48 +000079 } else {
Samuel Thibault67e3eee2016-02-22 22:29:21 +010080 m = (struct mbuf *) slirp->m_freelist.qh_link;
bellardf0cbd3e2004-04-22 00:10:48 +000081 remque(m);
82 }
ths5fafdf22007-09-16 21:08:06 +000083
bellardf0cbd3e2004-04-22 00:10:48 +000084 /* Insert it in the used list */
Jan Kiszka460fec62009-06-24 14:42:31 +020085 insque(m,&slirp->m_usedlist);
bellardf0cbd3e2004-04-22 00:10:48 +000086 m->m_flags = (flags | M_USEDLIST);
ths5fafdf22007-09-16 21:08:06 +000087
bellardf0cbd3e2004-04-22 00:10:48 +000088 /* Initialise it */
Anthony Liguori8fe30462011-02-14 14:24:24 -060089 m->m_size = SLIRP_MSIZE - offsetof(struct mbuf, m_dat);
bellardf0cbd3e2004-04-22 00:10:48 +000090 m->m_data = m->m_dat;
91 m->m_len = 0;
blueswir1511d2b12009-03-07 15:32:56 +000092 m->m_nextpkt = NULL;
93 m->m_prevpkt = NULL;
Guillaume Subironfc3779a2015-12-19 22:24:56 +010094 m->resolution_requested = false;
Fabien Chouteau1ab74ce2011-08-01 18:18:37 +020095 m->expiration_date = (uint64_t)-1;
Stefan Weilecc804c2015-08-29 09:12:35 +020096 DEBUG_ARG("m = %p", m);
bellardf0cbd3e2004-04-22 00:10:48 +000097 return m;
98}
99
100void
blueswir1511d2b12009-03-07 15:32:56 +0000101m_free(struct mbuf *m)
bellardf0cbd3e2004-04-22 00:10:48 +0000102{
ths5fafdf22007-09-16 21:08:06 +0000103
bellardf0cbd3e2004-04-22 00:10:48 +0000104 DEBUG_CALL("m_free");
Stefan Weilecc804c2015-08-29 09:12:35 +0200105 DEBUG_ARG("m = %p", m);
ths5fafdf22007-09-16 21:08:06 +0000106
bellardf0cbd3e2004-04-22 00:10:48 +0000107 if(m) {
108 /* Remove from m_usedlist */
109 if (m->m_flags & M_USEDLIST)
110 remque(m);
ths5fafdf22007-09-16 21:08:06 +0000111
bellardf0cbd3e2004-04-22 00:10:48 +0000112 /* If it's M_EXT, free() it */
Peter Maydell70f2e642017-02-04 23:08:34 +0000113 if (m->m_flags & M_EXT) {
114 g_free(m->m_ext);
115 }
bellardf0cbd3e2004-04-22 00:10:48 +0000116 /*
117 * Either free() it or put it on the free list
118 */
119 if (m->m_flags & M_DOFREE) {
Jan Kiszka460fec62009-06-24 14:42:31 +0200120 m->slirp->mbuf_alloced--;
Peter Maydell70f2e642017-02-04 23:08:34 +0000121 g_free(m);
bellardf0cbd3e2004-04-22 00:10:48 +0000122 } else if ((m->m_flags & M_FREELIST) == 0) {
Jan Kiszka460fec62009-06-24 14:42:31 +0200123 insque(m,&m->slirp->m_freelist);
bellardf0cbd3e2004-04-22 00:10:48 +0000124 m->m_flags = M_FREELIST; /* Clobber other flags */
125 }
126 } /* if(m) */
127}
128
129/*
130 * Copy data from one mbuf to the end of
Peter Maydell70f2e642017-02-04 23:08:34 +0000131 * the other.. if result is too big for one mbuf, allocate
bellardf0cbd3e2004-04-22 00:10:48 +0000132 * an M_EXT data segment
133 */
134void
blueswir1511d2b12009-03-07 15:32:56 +0000135m_cat(struct mbuf *m, struct mbuf *n)
bellardf0cbd3e2004-04-22 00:10:48 +0000136{
137 /*
138 * If there's no room, realloc
139 */
140 if (M_FREEROOM(m) < n->m_len)
141 m_inc(m,m->m_size+MINCSIZE);
ths5fafdf22007-09-16 21:08:06 +0000142
bellardf0cbd3e2004-04-22 00:10:48 +0000143 memcpy(m->m_data+m->m_len, n->m_data, n->m_len);
144 m->m_len += n->m_len;
145
146 m_free(n);
147}
148
149
150/* make m size bytes large */
151void
blueswir1511d2b12009-03-07 15:32:56 +0000152m_inc(struct mbuf *m, int size)
bellardf0cbd3e2004-04-22 00:10:48 +0000153{
bellard4b6ccfd2006-05-01 10:59:02 +0000154 int datasize;
155
bellardf0cbd3e2004-04-22 00:10:48 +0000156 /* some compiles throw up on gotos. This one we can fake. */
157 if(m->m_size>size) return;
158
159 if (m->m_flags & M_EXT) {
bellard4b6ccfd2006-05-01 10:59:02 +0000160 datasize = m->m_data - m->m_ext;
Peter Maydell70f2e642017-02-04 23:08:34 +0000161 m->m_ext = g_realloc(m->m_ext, size);
bellard4b6ccfd2006-05-01 10:59:02 +0000162 m->m_data = m->m_ext + datasize;
bellardf0cbd3e2004-04-22 00:10:48 +0000163 } else {
bellardf0cbd3e2004-04-22 00:10:48 +0000164 char *dat;
165 datasize = m->m_data - m->m_dat;
Peter Maydell70f2e642017-02-04 23:08:34 +0000166 dat = g_malloc(size);
bellardf0cbd3e2004-04-22 00:10:48 +0000167 memcpy(dat, m->m_dat, m->m_size);
ths3b46e622007-09-17 08:09:54 +0000168
bellardf0cbd3e2004-04-22 00:10:48 +0000169 m->m_ext = dat;
170 m->m_data = m->m_ext + datasize;
171 m->m_flags |= M_EXT;
172 }
ths5fafdf22007-09-16 21:08:06 +0000173
bellardf0cbd3e2004-04-22 00:10:48 +0000174 m->m_size = size;
175
176}
177
178
179
180void
blueswir1511d2b12009-03-07 15:32:56 +0000181m_adj(struct mbuf *m, int len)
bellardf0cbd3e2004-04-22 00:10:48 +0000182{
183 if (m == NULL)
184 return;
185 if (len >= 0) {
186 /* Trim from head */
187 m->m_data += len;
188 m->m_len -= len;
189 } else {
190 /* Trim from tail */
191 len = -len;
192 m->m_len -= len;
193 }
194}
195
196
197/*
198 * Copy len bytes from m, starting off bytes into n
199 */
200int
blueswir1511d2b12009-03-07 15:32:56 +0000201m_copy(struct mbuf *n, struct mbuf *m, int off, int len)
bellardf0cbd3e2004-04-22 00:10:48 +0000202{
203 if (len > M_FREEROOM(n))
204 return -1;
205
206 memcpy((n->m_data + n->m_len), (m->m_data + off), len);
207 n->m_len += len;
208 return 0;
209}
210
211
212/*
213 * Given a pointer into an mbuf, return the mbuf
214 * XXX This is a kludge, I should eliminate the need for it
215 * Fortunately, it's not used often
216 */
217struct mbuf *
Jan Kiszka460fec62009-06-24 14:42:31 +0200218dtom(Slirp *slirp, void *dat)
bellardf0cbd3e2004-04-22 00:10:48 +0000219{
220 struct mbuf *m;
ths5fafdf22007-09-16 21:08:06 +0000221
bellardf0cbd3e2004-04-22 00:10:48 +0000222 DEBUG_CALL("dtom");
Stefan Weilecc804c2015-08-29 09:12:35 +0200223 DEBUG_ARG("dat = %p", dat);
bellardf0cbd3e2004-04-22 00:10:48 +0000224
225 /* bug corrected for M_EXT buffers */
Samuel Thibault67e3eee2016-02-22 22:29:21 +0100226 for (m = (struct mbuf *) slirp->m_usedlist.qh_link;
227 (struct quehead *) m != &slirp->m_usedlist;
Jan Kiszka460fec62009-06-24 14:42:31 +0200228 m = m->m_next) {
bellardf0cbd3e2004-04-22 00:10:48 +0000229 if (m->m_flags & M_EXT) {
230 if( (char *)dat>=m->m_ext && (char *)dat<(m->m_ext + m->m_size) )
231 return m;
232 } else {
233 if( (char *)dat >= m->m_dat && (char *)dat<(m->m_dat + m->m_size) )
234 return m;
235 }
236 }
ths5fafdf22007-09-16 21:08:06 +0000237
bellardf0cbd3e2004-04-22 00:10:48 +0000238 DEBUG_ERROR((dfd, "dtom failed"));
ths5fafdf22007-09-16 21:08:06 +0000239
bellardf0cbd3e2004-04-22 00:10:48 +0000240 return (struct mbuf *)0;
241}