[PATCH RFC 07/12] accel/kvm: Move post-conversion updates to a separate helper

[Michael Roth <michael.roth@amd.com>]

Currently memory attribute conversions are followed up by other
bookkeeping tasks like discarding unused memory or issuing iommufd
notifications. Move these tasks to a separate post-conversions helper to
better compartmentalize and track these tasks, and in doing so lay the
groundwork for a pre-conversion helper which will be needed in the
future.

Signed-off-by: Michael Roth <michael.roth@amd.com>
---
 accel/kvm/kvm-all.c | 30 +++++++++++++++++++++---------
 1 file changed, 21 insertions(+), 9 deletions(-)

diff --git a/accel/kvm/kvm-all.c b/accel/kvm/kvm-all.c
index a1832712a4..0e6ff2de4b 100644
--- a/accel/kvm/kvm-all.c
+++ b/accel/kvm/kvm-all.c
@@ -3445,20 +3445,26 @@ static int kvm_convert_section(MemoryRegionSection *section, bool to_private)
 {
     hwaddr start = section->offset_within_address_space;
     hwaddr size = int128_get64(section->size);
-    MemoryRegion *mr = section->mr;
-    ram_addr_t offset;
-    RAMBlock *rb;
-    void *addr;
-    int ret = -EINVAL;
+    int ret;
 
     if (to_private) {
         ret = kvm_set_memory_attributes_private(start, size);
     } else {
         ret = kvm_set_memory_attributes_shared(start, size);
     }
-    if (ret) {
-        return ret;
-    }
+
+    return ret;
+}
+
+static int kvm_post_convert_section(MemoryRegionSection *section, bool to_private)
+{
+    hwaddr start = section->offset_within_address_space;
+    hwaddr size = int128_get64(section->size);
+    MemoryRegion *mr = section->mr;
+    ram_addr_t offset;
+    RAMBlock *rb;
+    void *addr;
+    int ret;
 
     addr = memory_region_get_ram_ptr(mr) + section->offset_within_region;
     rb = qemu_ram_block_from_host(addr, false, &offset);
@@ -3485,7 +3491,7 @@ static int kvm_convert_section(MemoryRegionSection *section, bool to_private)
         ret = ram_block_discard_guest_memfd_range(rb, offset, size);
     }
 
-    return ret;
+    return 0;
 }
 
 int kvm_convert_memory(hwaddr start, hwaddr size, bool to_private)
@@ -3533,6 +3539,12 @@ int kvm_convert_memory(hwaddr start, hwaddr size, bool to_private)
         }
 
         ret = kvm_convert_section(&section, to_private);
+        if (ret) {
+            memory_region_unref(section.mr);
+            break;
+        }
+
+        ret = kvm_post_convert_section(&section, to_private);
         memory_region_unref(section.mr);
 
         if (ret) {
-- 
2.43.0