[src/trunk]: src/sys/rump/net/lib/libshmif * include a magic number in the bu...

[pooka <pooka%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/fd922d48e1ce
branches:  trunk
changeset: 757063:fd922d48e1ce
user:      pooka <pooka%NetBSD.org@localhost>
date:      Thu Aug 12 18:17:23 2010 +0000

description:
* include a magic number in the bus format
* simplify offset calculations by making them start from beginning of data

diffstat:

 sys/rump/net/lib/libshmif/dumpbus.c  |  12 +++++++-----
 sys/rump/net/lib/libshmif/if_shmem.c |  32 ++++++++++++++++----------------
 sys/rump/net/lib/libshmif/shmifvar.h |  15 ++++++++++++---
 3 files changed, 35 insertions(+), 24 deletions(-)

diffs (166 lines):

diff -r 72f81b8d6148 -r fd922d48e1ce sys/rump/net/lib/libshmif/dumpbus.c
--- a/sys/rump/net/lib/libshmif/dumpbus.c       Thu Aug 12 17:33:55 2010 +0000
+++ b/sys/rump/net/lib/libshmif/dumpbus.c       Thu Aug 12 18:17:23 2010 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: dumpbus.c,v 1.3 2010/08/12 17:33:55 pooka Exp $        */
+/*     $NetBSD: dumpbus.c,v 1.4 2010/08/12 18:17:23 pooka Exp $        */
 
 /*
  * Little utility to convert shmif bus traffic to a pcap file
@@ -67,8 +67,11 @@
                err(1, "mmap");
 
        bmem = busmem;
-       if (bmem->shm_version != 1)
-               errx(1, "cannot handle bus version %d", bmem->shm_version);
+       if (bmem->shm_magic != SHMIF_MAGIC)
+               errx(1, "%s not a shmif bus", argv[0]);
+       if (bmem->shm_version != SHMIF_VERSION)
+               errx(1, "bus vesrsion %d, program %d",
+                   bmem->shm_version, SHMIF_VERSION);
        printf("bus version %d, lock: %d, generation: %d, lastoff: 0x%x\n",
            bmem->shm_version, bmem->shm_lock, bmem->shm_gen, bmem->shm_last);
 
@@ -106,12 +109,11 @@
                pktlen = *(uint32_t *)curbus;
                curbus += sizeof(pktlen);
 
-               /* quirk */
                if (pktlen == 0)
                        continue;
 
                printf("packet %d, offset 0x%x, length 0x%x\n",
-                   i++, curbus - (uint8_t *)(bmem + 1), pktlen);
+                   i++, curbus - bmem->shm_data, pktlen);
 
                if (!pcapfile || pktlen == 0) {
                        curbus += pktlen;
diff -r 72f81b8d6148 -r fd922d48e1ce sys/rump/net/lib/libshmif/if_shmem.c
--- a/sys/rump/net/lib/libshmif/if_shmem.c      Thu Aug 12 17:33:55 2010 +0000
+++ b/sys/rump/net/lib/libshmif/if_shmem.c      Thu Aug 12 18:17:23 2010 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: if_shmem.c,v 1.16 2010/08/12 17:33:55 pooka Exp $      */
+/*     $NetBSD: if_shmem.c,v 1.17 2010/08/12 18:17:23 pooka Exp $      */
 
 /*
  * Copyright (c) 2009 Antti Kantee.  All Rights Reserved.
@@ -28,7 +28,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: if_shmem.c,v 1.16 2010/08/12 17:33:55 pooka Exp $");
+__KERNEL_RCSID(0, "$NetBSD: if_shmem.c,v 1.17 2010/08/12 18:17:23 pooka Exp $");
 
 #include <sys/param.h>
 #include <sys/atomic.h>
@@ -81,8 +81,7 @@
 
 #define BUSMEM_SIZE (1024*1024) /* need write throttling? */
 
-/* just in case ... */
-static const uint32_t busversion = 1;
+static const uint32_t busversion = SHMIF_VERSION;
 
 static void shmif_rcv(void *);
 
@@ -123,18 +122,18 @@
 
        KASSERT(len < (BUSMEM_SIZE - IFMEM_DATA) && off <= BUSMEM_SIZE);
        chunk = MIN(len, BUSMEM_SIZE - off);
-       memcpy(dest, (uint8_t *)sc->sc_busmem + off, chunk);
+       memcpy(dest, sc->sc_busmem->shm_data + off, chunk);
        len -= chunk;
 
        if (len == 0)
                return off + chunk;
 
        /* else, wraps around */
-       off = IFMEM_DATA;
+       off = 0;
        sc->sc_prevgen = sc->sc_busmem->shm_gen;
 
        /* finish reading */
-       memcpy((uint8_t *)dest + chunk, (uint8_t *)sc->sc_busmem + off, len);
+       memcpy((uint8_t *)dest + chunk, sc->sc_busmem->shm_data + off, len);
        return off + len;
 }
 
@@ -143,26 +142,25 @@
 {
        size_t chunk;
 
-       KASSERT(len < (BUSMEM_SIZE - IFMEM_DATA) && off <= BUSMEM_SIZE
-           && off >= IFMEM_DATA);
+       KASSERT(len < (BUSMEM_SIZE - IFMEM_DATA) && off <= BUSMEM_SIZE);
 
        chunk = MIN(len, BUSMEM_SIZE - off);
-       memcpy((uint8_t *)sc->sc_busmem + off, data, chunk);
+       memcpy(sc->sc_busmem->shm_data + off, data, chunk);
        len -= chunk;
 
        if (len == 0)
                return off + chunk;
 
-       DPRINTF(("buswrite wrap: wrote %d bytes to %d, left %d to %d",
-           chunk, off, len, IFMEM_DATA));
+       DPRINTF(("buswrite wrap: wrote %d bytes to %d, left %d to 0",
+           chunk, off, len));
 
        /* else, wraps around */
-       off = IFMEM_DATA;
+       off = 0;
        sc->sc_prevgen = sc->sc_busmem->shm_gen;
        sc->sc_busmem->shm_gen++;
 
        /* finish writing */
-       memcpy((uint8_t *)sc->sc_busmem + off, (uint8_t *)data + chunk, len);
+       memcpy(sc->sc_busmem->shm_data + off, (uint8_t *)data + chunk, len);
        return off + len;
 }
 
@@ -216,9 +214,11 @@
        if (error)
                goto fail;
 
+       if (sc->sc_busmem->shm_magic && sc->sc_busmem->shm_magic != SHMIF_MAGIC)
+               panic("bus is not magical");
+       sc->sc_busmem->shm_magic = SHMIF_MAGIC;
+
        lockbus(sc);
-       if (sc->sc_busmem->shm_last == 0)
-               sc->sc_busmem->shm_last = IFMEM_DATA;
        sc->sc_nextpacket = sc->sc_busmem->shm_last;
        sc->sc_prevgen = sc->sc_busmem->shm_gen;
        unlockbus(sc);
diff -r 72f81b8d6148 -r fd922d48e1ce sys/rump/net/lib/libshmif/shmifvar.h
--- a/sys/rump/net/lib/libshmif/shmifvar.h      Thu Aug 12 17:33:55 2010 +0000
+++ b/sys/rump/net/lib/libshmif/shmifvar.h      Thu Aug 12 18:17:23 2010 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: shmifvar.h,v 1.1 2010/08/12 17:33:55 pooka Exp $       */
+/*     $NetBSD: shmifvar.h,v 1.2 2010/08/12 18:17:23 pooka Exp $       */
 
 /*-
  * Copyright (c) 2009 Antti Kantee.  All Rights Reserved.
@@ -30,11 +30,20 @@
 #ifndef _RUMP_NET_SHMIFVAR_H_
 #define _RUMP_NET_SHMIFVAR_H_
 
+#define SHMIF_MAGIC 0xca11d054
+#define SHMIF_VERSION 1
+
 struct shmif_mem {
-       uint32_t shm_lock;
+       uint32_t shm_magic;
+       uint32_t shm_version;
+
        uint32_t shm_gen;
+       uint32_t shm_first;
        uint32_t shm_last;
-       uint32_t shm_version;
+
+       uint32_t shm_lock;
+       uint32_t shm_spare[2];
+
        uint8_t shm_data[0];
 };