[Qemu-devel] [PATCH v8 09/20] exec: introduce target_words_bigendian() helper

[Greg Kurz <gkurz@linux.vnet.ibm.com>]

We currently have a virtio_is_big_endian() helper that provides the target
endianness to the virtio code. As of today, the helper returns a fixed
compile-time value. Of course, this will have to change if we want to
support target endianness changes at run-time.

Let's move the TARGET_WORDS_BIGENDIAN bits out to a new helper and have
virtio_is_big_endian() implemented on top of it.

This patch doesn't change any functionality.

Signed-off-by: Greg Kurz <gkurz@linux.vnet.ibm.com>
---
 exec.c                     |   11 +----------
 hw/virtio/virtio-pci.c     |    3 ---
 include/exec/cpu-common.h  |    1 +
 include/hw/virtio/virtio.h |    5 +++++
 4 files changed, 7 insertions(+), 13 deletions(-)

diff --git a/exec.c b/exec.c
index 4e179a6..a7d4431 100644
--- a/exec.c
+++ b/exec.c
@@ -2738,14 +2738,7 @@ int cpu_memory_rw_debug(CPUState *cpu, target_ulong addr,
 }
 #endif
 
-#if !defined(CONFIG_USER_ONLY)
-
-/*
- * A helper function for the _utterly broken_ virtio device model to find out if
- * it's running on a big endian machine. Don't do this at home kids!
- */
-bool virtio_is_big_endian(void);
-bool virtio_is_big_endian(void)
+bool target_words_bigendian(void)
 {
 #if defined(TARGET_WORDS_BIGENDIAN)
     return true;
@@ -2754,8 +2747,6 @@ bool virtio_is_big_endian(void)
 #endif
 }
 
-#endif
-
 #ifndef CONFIG_USER_ONLY
 bool cpu_physical_memory_is_io(hwaddr phys_addr)
 {
diff --git a/hw/virtio/virtio-pci.c b/hw/virtio/virtio-pci.c
index ce97514..390c8d2 100644
--- a/hw/virtio/virtio-pci.c
+++ b/hw/virtio/virtio-pci.c
@@ -89,9 +89,6 @@
 /* Flags track per-device state like workarounds for quirks in older guests. */
 #define VIRTIO_PCI_FLAG_BUS_MASTER_BUG  (1 << 0)
 
-/* HACK for virtio to determine if it's running a big endian guest */
-bool virtio_is_big_endian(void);
-
 static void virtio_pci_bus_new(VirtioBusState *bus, size_t bus_size,
                                VirtIOPCIProxy *dev);
 
diff --git a/include/exec/cpu-common.h b/include/exec/cpu-common.h
index a21b65a..eb798c1 100644
--- a/include/exec/cpu-common.h
+++ b/include/exec/cpu-common.h
@@ -122,4 +122,5 @@ void qemu_ram_foreach_block(RAMBlockIterFunc func, void *opaque);
 
 #endif
 
+bool target_words_bigendian(void);
 #endif /* !CPU_COMMON_H */
diff --git a/include/hw/virtio/virtio.h b/include/hw/virtio/virtio.h
index 3505ce5..daf0bb2 100644
--- a/include/hw/virtio/virtio.h
+++ b/include/hw/virtio/virtio.h
@@ -255,4 +255,9 @@ void virtio_queue_set_host_notifier_fd_handler(VirtQueue *vq, bool assign,
                                                bool set_handler);
 void virtio_queue_notify_vq(VirtQueue *vq);
 void virtio_irq(VirtQueue *vq);
+
+static inline bool virtio_is_big_endian(void)
+{
+    return target_words_bigendian();
+}
 #endif