split out mbuf scatter gather function

2 files changed, 113 insertions, 0 deletions

diff --git a/sys/crypto/crypto.h b/sys/crypto/crypto.h
index f4515fb6abb..9e3d688acab 100644
--- a/sys/crypto/crypto.h
+++ b/sys/crypto/crypto.h
@@ -157,6 +157,9 @@ extern int crypto_register(u_int32_t, int, void *, void *, void *);
 extern int crypto_unregister(u_int32_t, int);
 extern int32_t crypto_get_driverid(void);
 
+struct mbuf;
+int	mbuf2pages(struct mbuf *, int *, long *, int *, int, int *);
+
 extern struct cryptop *crypto_getreq(int);
 extern void crypto_freereq(struct cryptop *);
 #endif /* _KERNEL */
diff --git a/sys/crypto/mbuf.c b/sys/crypto/mbuf.c
new file mode 100644
index 00000000000..3ac7ebcc405
--- /dev/null
+++ b/sys/crypto/mbuf.c
@@ -0,0 +1,110 @@
+/*      $OpenBSD: mbuf.c,v 1.1 2000/04/19 00:10:35 deraadt Exp $	*/
+
+/*
+ * Copyright (c) 1999 Theo de Raadt
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *   notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *   notice, this list of conditions and the following disclaimer in the
+ *   documentation and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote products
+ *   derived from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
+ * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+ * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include <sys/param.h>
+#include <sys/systm.h>
+#include <sys/proc.h>
+#include <sys/errno.h>
+#include <sys/malloc.h>
+#include <sys/kernel.h>
+#include <sys/mbuf.h>
+#include <vm/vm.h>
+#include <vm/vm_extern.h>
+#include <vm/pmap.h>
+#include <machine/pmap.h>
+
+#include <crypto/crypto.h>
+
+int
+mbuf2pages(m, np, pp, lp, maxp, nicep)
+	struct mbuf *m;
+	int *np;
+	long *pp;
+	int *lp;
+	int maxp;
+	int *nicep;
+{
+	struct  mbuf *m0;
+	int npa = 0, tlen = 0;
+
+	/* generate a [pa,len] array from an mbuf */
+	for (m0 = m; m; m = m->m_next) {
+		void *va;
+		long pg, npg;
+		int len, off;
+
+		if (m->m_len == 0)
+			continue;
+		len = m->m_len;
+		tlen += len;
+		va = m->m_data;
+
+		lp[npa] = len;
+		pp[npa] = vtophys(va);
+		pg = pp[npa] & ~PAGE_MASK;
+		off = (long)va & PAGE_MASK;
+
+		while (len + off > PAGE_SIZE) {
+			va = va + PAGE_SIZE - off;
+			npg = vtophys(va);
+			if (npg != pg) {
+				/* FUCKED UP condition */
+				if (++npa > maxp)
+					return (0);
+				continue;
+			}
+			lp[npa] = PAGE_SIZE - off;
+			off = 0;
+
+			if (++npa > maxp)
+				return (0);
+
+			lp[npa] = len - (PAGE_SIZE - off);
+			len -= lp[npa];
+			pp[npa] = vtophys(va);
+		}
+
+		if (++npa == maxp)
+			return (0);
+	}
+
+	if (nicep) {
+		int nice = 1;
+		int i;
+
+		/* see if each [pa,len] entry is long-word aligned */
+		for (i = 0; i < npa; i++)
+			if ((lp[i] & 3) || (pp[i] & 3))
+				nice = 0;
+		*nicep = nice;
+	}
+
+	*np = npa;
+	return (tlen);
+}