Finally getting around to finishing a c2k10 diff. This no longer a) panics
nor b) drops ipsec traffic on my test box.
The code to split a single mbuf is used in both m_inject and m_split, so
roll that into its own function, m_splitm, and make them wrappers around
the new function. There's at least one other place it could be used, but
this will do for now.
As said above, this affects ipsec setups, it also affects A-MSDU wireless
traffic; tests of both and (off-list) reports will earn you my love.
- Bert
Index: kern/uipc_mbuf.c
===================================================================
RCS file: /cvs/src/sys/kern/uipc_mbuf.c,v
retrieving revision 1.143
diff -u -p -r1.143 uipc_mbuf.c
--- kern/uipc_mbuf.c 15 Jul 2010 09:45:09 -0000 1.143
+++ kern/uipc_mbuf.c 11 Sep 2010 17:07:07 -0000
@@ -110,6 +110,8 @@ struct pool mclpools[MCLPOOLS];
int m_clpool(u_int);
+struct mbuf *m_splitm(struct mbuf *, int, int);
+
int max_linkhdr; /* largest link-level header */
int max_protohdr; /* largest protocol header */
int max_hdr; /* largest link+protocol header */
@@ -1064,130 +1066,85 @@ m_getptr(struct mbuf *m, int loc, int *o
}
/*
- * Inject a new mbuf chain of length siz in mbuf chain m0 at
- * position len0. Returns a pointer to the first injected mbuf, or
- * NULL on failure (m0 is left undisturbed). Note that if there is
- * enough space for an object of size siz in the appropriate position,
+ * Inject a new mbuf chain of length len in mbuf chain m at
+ * position off. Returns a pointer to the first injected mbuf, or
+ * NULL on failure (m is left undisturbed). Note that if there is
+ * enough space for an object of size len in the appropriate position,
* no memory will be allocated. Also, there will be no data movement in
- * the first len0 bytes (pointers to that will remain valid).
+ * the first off bytes (pointers to that will remain valid).
*
- * XXX It is assumed that siz is less than the size of an mbuf at the moment.
+ * XXX It is assumed that len is less than the size of an mbuf at the moment.
*/
struct mbuf *
-m_inject(struct mbuf *m0, int len0, int siz, int wait)
+m_inject(struct mbuf *m, int off, int len, int wait)
{
- struct mbuf *m, *n, *n2 = NULL, *n3;
- unsigned len = len0, remain;
+ struct mbuf *n, *o, *p;
+ int off1;
- if ((siz >= MHLEN) || (len0 <= 0))
- return (NULL);
- for (m = m0; m && len > m->m_len; m = m->m_next)
- len -= m->m_len;
- if (m == NULL)
+ if (len > MHLEN || len <= 0)
return (NULL);
- remain = m->m_len - len;
- if (remain == 0) {
- if ((m->m_next) && (M_LEADINGSPACE(m->m_next) >= siz)) {
- m->m_next->m_len += siz;
- if (m0->m_flags & M_PKTHDR)
- m0->m_pkthdr.len += siz;
- m->m_next->m_data -= siz;
- return m->m_next;
- }
- } else {
- n2 = m_copym2(m, len, remain, wait);
- if (n2 == NULL)
- return (NULL);
- }
- MGET(n, wait, MT_DATA);
- if (n == NULL) {
- if (n2)
- m_freem(n2);
+ if ((n = m_getptr(m, off, &off1)) == NULL)
+ return (NULL);
+
+ if ((o = m_get(wait, MT_DATA)) == NULL)
+ return (NULL);
+
+ if ((p = m_splitm(n, off1, wait)) == NULL) {
+ m_freem(o);
return (NULL);
}
- n->m_len = siz;
- if (m0->m_flags & M_PKTHDR)
- m0->m_pkthdr.len += siz;
- m->m_len -= remain; /* Trim */
- if (n2) {
- for (n3 = n; n3->m_next != NULL; n3 = n3->m_next)
- ;
- n3->m_next = n2;
- } else
- n3 = n;
- for (; n3->m_next != NULL; n3 = n3->m_next)
- ;
- n3->m_next = m->m_next;
- m->m_next = n;
- return n;
+ o->m_len = len;
+ o->m_next = p;
+ n->m_next = o;
+
+ if (m->m_flags & M_PKTHDR)
+ m->m_pkthdr.len += len;
+
+ return (o);
}
/*
- * Partition an mbuf chain in two pieces, returning the tail --
- * all but the first len0 bytes. In case of failure, it returns NULL and
- * attempts to restore the chain to its original state.
+ * Create a pair of mbufs, leaving the chain intact.
*/
struct mbuf *
-m_split(struct mbuf *m0, int len0, int wait)
+m_splitm(struct mbuf *m, int off, int wait)
{
- struct mbuf *m, *n;
- unsigned len = len0, remain, olen;
+ struct mbuf *n;
- for (m = m0; m && len > m->m_len; m = m->m_next)
- len -= m->m_len;
- if (m == NULL)
+ if (off > m->m_len)
return (NULL);
- remain = m->m_len - len;
- if (m0->m_flags & M_PKTHDR) {
- MGETHDR(n, wait, m0->m_type);
- if (n == NULL)
- return (NULL);
- if (m_dup_pkthdr(n, m0)) {
- m_freem(n);
- return (NULL);
- }
- n->m_pkthdr.len -= len0;
- olen = m0->m_pkthdr.len;
- m0->m_pkthdr.len = len0;
- if (m->m_flags & M_EXT)
- goto extpacket;
- if (remain > MHLEN) {
- /* m can't be the lead packet */
- MH_ALIGN(n, 0);
- n->m_next = m_split(m, len, wait);
- if (n->m_next == NULL) {
- (void) m_free(n);
- m0->m_pkthdr.len = olen;
- return (NULL);
- } else
- return (n);
- } else
- MH_ALIGN(n, remain);
- } else if (remain == 0) {
- n = m->m_next;
- m->m_next = NULL;
- return (n);
- } else {
- MGET(n, wait, m->m_type);
- if (n == NULL)
- return (NULL);
- M_ALIGN(n, remain);
- }
-extpacket:
- if (m->m_flags & M_EXT) {
- n->m_ext = m->m_ext;
- MCLADDREFERENCE(m, n);
- n->m_data = m->m_data + len;
- } else {
- bcopy(mtod(m, caddr_t) + len, mtod(n, caddr_t), remain);
- }
- n->m_len = remain;
- m->m_len = len;
+
+ /* Potential pkthdr issues in m_copym? */
+ if ((n = m_copym(m, off, m->m_len - off, wait)) == NULL)
+ return (NULL);
+
+ m->m_len = off;
n->m_next = m->m_next;
- m->m_next = NULL;
+ m->m_next = n;
+
return (n);
+}
+
+/*
+ * Break mbuf chain into two parts at the specified offset.
+ */
+struct mbuf *
+m_split(struct mbuf *m, int off, int wait)
+{
+ struct mbuf *n, *o;
+ int off1;
+
+ if ((n = m_getptr(m, off, &off1)) == NULL)
+ return (NULL);
+
+ if ((o = m_splitm(n, off1, wait)) == NULL)
+ return (NULL);
+
+ n->m_next = NULL;
+
+ return (o);
}
/*
