vhost-user-test: support VHOST_USER_PROTOCOL_F_CROSS_ENDIAN

This will be useful to run the qtest for ppc64 targets on (for example)
x86_64 hosts.
Reviewed-by: NMarc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>
Reviewed-by: NThomas Huth <thuth@redhat.com>
Message-Id: <1543851204-41186-10-git-send-email-pbonzini@redhat.com>

tests/vhost-user-test.c

@@ -51,6 +51,7 @@
 #define VHOST_USER_F_PROTOCOL_FEATURES 30
 #define VHOST_USER_PROTOCOL_F_MQ 0
 #define VHOST_USER_PROTOCOL_F_LOG_SHMFD 1
+#define VHOST_USER_PROTOCOL_F_CROSS_ENDIAN   6
 
 #define VHOST_LOG_PAGE 0x1000
 
@@ -251,7 +252,7 @@ static void wait_for_fds(TestServer *s)
 
 static void read_guest_mem_server(TestServer *s)
 {
-    uint32_t *guest_mem;
+    uint8_t *guest_mem;
     int i, j;
     size_t size;
 
@@ -278,8 +279,8 @@ static void read_guest_mem_server(TestServer *s)
         g_assert(guest_mem != MAP_FAILED);
         guest_mem += (s->memory.regions[i].mmap_offset / sizeof(*guest_mem));
 
-        for (j = 0; j < 256; j++) {
-            uint32_t a = readl(s->memory.regions[i].guest_phys_addr + j*4);
+        for (j = 0; j < 1024; j++) {
+            uint32_t a = readb(s->memory.regions[i].guest_phys_addr + j);
             uint32_t b = guest_mem[j];
 
             g_assert_cmpint(a, ==, b);
@@ -367,6 +368,7 @@ static void chr_read(void *opaque, const uint8_t *buf, int size)
         msg.flags |= VHOST_USER_REPLY_MASK;
         msg.size = sizeof(m.payload.u64);
         msg.payload.u64 = 1 << VHOST_USER_PROTOCOL_F_LOG_SHMFD;
+        msg.payload.u64 |= 1 << VHOST_USER_PROTOCOL_F_CROSS_ENDIAN;
         if (s->queues > 1) {
             msg.payload.u64 |= 1 << VHOST_USER_PROTOCOL_F_MQ;
         }