Module Name: src
Committed By: roy
Date: Sun Feb 14 19:33:29 UTC 2021
Modified Files:
src/sys/net: if_gre.c if_gre.h
Log Message:
if_gre: Remove alignment checks in favour copying to stack
Makes the code a lot simpler, idea from dyoung@
To generate a diff of this commit:
cvs rdiff -u -r1.179 -r1.180 src/sys/net/if_gre.c
cvs rdiff -u -r1.48 -r1.49 src/sys/net/if_gre.h
Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.
Modified files:
Index: src/sys/net/if_gre.c
diff -u src/sys/net/if_gre.c:1.179 src/sys/net/if_gre.c:1.180
--- src/sys/net/if_gre.c:1.179 Sat Feb 13 13:00:16 2021
+++ src/sys/net/if_gre.c Sun Feb 14 19:33:29 2021
@@ -1,4 +1,4 @@
-/* $NetBSD: if_gre.c,v 1.179 2021/02/13 13:00:16 roy Exp $ */
+/* $NetBSD: if_gre.c,v 1.180 2021/02/14 19:33:29 roy Exp $ */
/*
* Copyright (c) 1998, 2008 The NetBSD Foundation, Inc.
@@ -45,7 +45,7 @@
*/
#include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: if_gre.c,v 1.179 2021/02/13 13:00:16 roy Exp $");
+__KERNEL_RCSID(0, "$NetBSD: if_gre.c,v 1.180 2021/02/14 19:33:29 roy Exp $");
#ifdef _KERNEL_OPT
#include "opt_atalk.h"
@@ -142,6 +142,8 @@ int gre_debug = 0;
#define GRE_DPRINTF(__sc, __fmt, ...) do { } while (/*CONSTCOND*/0)
#endif /* GRE_DEBUG */
+CTASSERT(sizeof(struct gre_h) == 4);
+
int ip_gre_ttl = GRE_TTL;
static u_int gre_count;
@@ -374,7 +376,7 @@ gre_receive(struct socket *so, void *arg
{
struct gre_softc *sc = (struct gre_softc *)arg;
int rc;
- const struct gre_h *gh;
+ struct gre_h gh;
struct mbuf *m;
GRE_DPRINTF(sc, "enter\n");
@@ -396,24 +398,16 @@ gre_receive(struct socket *so, void *arg
return;
}
- /* Enforce alignment */
- if (GRE_HDR_ALIGNED_P(mtod(m, void *)) == 0) {
- if ((m = m_copyup(m, sizeof(struct gre_h), 0)) == NULL) {
- /* XXXJRT new stat, please */
- GRE_DPRINTF(sc, "m_copyup failed\n");
- sc->sc_pullup_ev.ev_count++;
- return;
- }
- } else if (__predict_false(m->m_len < sizeof(struct gre_h))) {
- if ((m = m_pullup(m, sizeof(struct gre_h))) == NULL) {
+ if (__predict_false(m->m_len < sizeof(gh))) {
+ if ((m = m_pullup(m, sizeof(gh))) == NULL) {
GRE_DPRINTF(sc, "m_pullup failed\n");
sc->sc_pullup_ev.ev_count++;
return;
}
}
- gh = mtod(m, const struct gre_h *);
+ memcpy(&gh, mtod(m, void *), sizeof(gh));
- if (gre_input(sc, m, gh) == 0) {
+ if (gre_input(sc, m, &gh) == 0) {
sc->sc_unsupp_ev.ev_count++;
GRE_DPRINTF(sc, "dropping unsupported\n");
m_freem(m);
@@ -898,7 +892,7 @@ gre_output(struct ifnet *ifp, struct mbu
{
int error = 0;
struct gre_softc *sc = ifp->if_softc;
- struct gre_h *gh;
+ struct gre_h gh = { .flags = 0 };
uint16_t etype = 0;
KASSERT((m->m_flags & M_PKTHDR) != 0);
@@ -950,17 +944,15 @@ gre_output(struct ifnet *ifp, struct mbu
}
#endif
- M_PREPEND(m, sizeof(*gh), M_DONTWAIT);
+ M_PREPEND(m, sizeof(gh), M_DONTWAIT);
if (m == NULL) {
IF_DROP(&ifp->if_snd);
error = ENOBUFS;
goto end;
}
- gh = mtod(m, struct gre_h *);
- KASSERT(GRE_HDR_ALIGNED_P(gh));
- gh->flags = 0;
- gh->ptype = etype;
+ gh.ptype = etype;
+ memcpy(mtod(m, void *), &gh, sizeof(gh));
/* XXX Need to handle IP ToS. Look at how I handle IP TTL. */
if_statadd2(ifp, if_opackets, 1, if_obytes, m->m_pkthdr.len);
Index: src/sys/net/if_gre.h
diff -u src/sys/net/if_gre.h:1.48 src/sys/net/if_gre.h:1.49
--- src/sys/net/if_gre.h:1.48 Fri Feb 12 19:57:49 2021
+++ src/sys/net/if_gre.h Sun Feb 14 19:33:29 2021
@@ -1,4 +1,4 @@
-/* $NetBSD: if_gre.h,v 1.48 2021/02/12 19:57:49 roy Exp $ */
+/* $NetBSD: if_gre.h,v 1.49 2021/02/14 19:33:29 roy Exp $ */
/*
* Copyright (c) 1998, 2008 The NetBSD Foundation, Inc.
@@ -131,15 +131,6 @@ struct gre_h {
Present if (rt_pres == 1)
*/
};
-#ifdef __NO_STRICT_ALIGNMENT
-#define GRE_HDR_ALIGNED_P(gh) 1
-#else
-#define GRE_HDR_ALIGNED_P(gh) ((((vaddr_t) (gh)) & 3) == 0)
-#endif
-#ifdef __CTASSERT
-__CTASSERT(sizeof(struct gre_h) == 4);
-#endif
-
#define GRE_CP 0x8000 /* Checksum Present */
#define GRE_RP 0x4000 /* Routing Present */
#define GRE_KP 0x2000 /* Key Present */
