On 7/3/25 23:39, Philippe Mathieu-Daudé wrote:
Use qemu_arch_available() to check at runtime if a target
architecture is built in.
Consider the maximum extent size of any architecture built in.
Signed-off-by: Philippe Mathieu-Daudé <phi...@linaro.org>
---
hw/virtio/virtio-mem.c | 28 ++++++++++++++++++++--------
1 file changed, 20 insertions(+), 8 deletions(-)
@@ -170,13 +171,24 @@ static bool virtio_mem_has_shared_zeropage(RAMBlock *rb)
* necessary (as the section size can change). But it's more likely that the
* section size will rather get smaller and not bigger over time.
*/
-#if defined(TARGET_X86_64) || defined(TARGET_I386) || defined(TARGET_S390X)
-#define VIRTIO_MEM_USABLE_EXTENT (2 * (128 * MiB))
-#elif defined(TARGET_ARM)
-#define VIRTIO_MEM_USABLE_EXTENT (2 * (512 * MiB))
-#else
-#error VIRTIO_MEM_USABLE_EXTENT not defined
-#endif
+static uint64_t virtio_mem_usable_extent_size(void)
+{
+ uint64_t size = 0;
+
+ assert(qemu_arch_available(QEMU_ARCH_ARM | QEMU_ARCH_I386 |
QEMU_ARCH_S390X));
I'm not sure this assertion is doing what I thought it'd do.
For example, building with --target-list=aarch64-softmmu,riscv32-softmmu,
this device is now linked in. However, riscv32 machines won't be able
to plug it until they allow TYPE_VIRTIO_MD_PCI in some of their
HotplugHandlerClass handlers. Still I'd like to catch this case here
to avoid bad surprises.
+ /*
+ * FIXME: We should use the maximum of instantiated vCPUs ARCH, but
+ * for now it is easier to take the maximum of any ARCH built in.
+ */
+ if (qemu_arch_available(QEMU_ARCH_I386 | QEMU_ARCH_S390X)) {
+ size = MAX(size, 2 * 128 * MiB);
+ }
+ if (qemu_arch_available(QEMU_ARCH_ARM)) {
+ size = MAX(size, 2 * 512 * MiB);
+ }
+
+ return size;
+}
