[Qemu-devel] [PATCH 2/3] Assume PPC64 host on PPC32 KVM

[Alexander Graf <agraf@suse.de>]

When talking to the kernel about dirty maps, we need to find out which
bits were actually set. This is done by set_bit and test_bit like
functiontality which uses the "long" variable type.

Now, with PPC32 userspace and PPC64 kernel space (which is pretty common),
we can't interpret the bits properly anymore, because we think long is
32 bits wide.

So for PPC dirty bitmap analysis, let's just assume we're always running
on a PPC64 host. Currently there is no dirty bitmap implementation for
PPC32 / PPCEMB anyways.

Unbreaks dirty logging on PPC.

Signed-off-by: Alexander Graf <agraf@suse.de>
---
 kvm-all.c |    6 ++++++
 1 files changed, 6 insertions(+), 0 deletions(-)

diff --git a/kvm-all.c b/kvm-all.c
index 824bb4c..bfaa623 100644
--- a/kvm-all.c
+++ b/kvm-all.c
@@ -357,7 +357,13 @@ int kvm_physical_sync_dirty_bitmap(target_phys_addr_t start_addr,
         for (phys_addr = mem->start_addr, addr = mem->phys_offset;
              phys_addr < mem->start_addr + mem->memory_size;
              phys_addr += TARGET_PAGE_SIZE, addr += TARGET_PAGE_SIZE) {
+#ifdef HOST_PPC
+             /* Big endian keeps us from having different long sizes in user and
+              * kernel space, so assume we're always on ppc64. */
+            uint64_t *bitmap = (uint64_t *)d.dirty_bitmap;
+#else
             unsigned long *bitmap = (unsigned long *)d.dirty_bitmap;
+#endif
             unsigned nr = (phys_addr - mem->start_addr) >> TARGET_PAGE_BITS;
             unsigned word = nr / (sizeof(*bitmap) * 8);
             unsigned bit = nr % (sizeof(*bitmap) * 8);
-- 
1.6.0.2