qemu-kvm/kvm-memory-Unify-the-definiton-of-ReplayRamPopulate-and-.patch

From a0a6a0d1131461f2695f28a673f410bbb33262ef Mon Sep 17 00:00:00 2001
From: Paolo Bonzini <pbonzini@redhat.com>
Date: Fri, 18 Jul 2025 18:11:28 +0200
Subject: [PATCH 113/115] memory: Unify the definiton of ReplayRamPopulate()
 and ReplayRamDiscard()

RH-Author: Paolo Bonzini <pbonzini@redhat.com>
RH-MergeRequest: 391: TDX support, including attestation and device assignment
RH-Jira: RHEL-15710 RHEL-20798 RHEL-49728
RH-Acked-by: Yash Mankad <None>
RH-Acked-by: Peter Xu <peterx@redhat.com>
RH-Acked-by: David Hildenbrand <david@redhat.com>
RH-Commit: [113/115] 8ad320473d66f2956d701a4625f815d2fcd8ae4b (bonzini/rhel-qemu-kvm)

Update ReplayRamDiscard() function to return the result and unify the
ReplayRamPopulate() and ReplayRamDiscard() to ReplayRamDiscardState() at
the same time due to their identical definitions. This unification
simplifies related structures, such as VirtIOMEMReplayData, which makes
it cleaner.

Reviewed-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Pankaj Gupta <pankaj.gupta@amd.com>
Reviewed-by: Xiaoyao Li <xiaoyao.li@intel.com>
Signed-off-by: Chenyi Qiang <chenyi.qiang@intel.com>
Link: https://lore.kernel.org/r/20250612082747.51539-4-chenyi.qiang@intel.com
Signed-off-by: Peter Xu <peterx@redhat.com>
(cherry picked from commit 2205b8466733f8c6e3306c964f31c5a7cac69dfa)
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
---
 hw/virtio/virtio-mem.c | 21 ++++++------
 include/exec/memory.h  | 74 ++++++++++++++++++++++++++++++++----------
 migration/ram.c        |  5 +--
 system/memory.c        | 12 +++----
 4 files changed, 76 insertions(+), 36 deletions(-)

diff --git a/hw/virtio/virtio-mem.c b/hw/virtio/virtio-mem.c
index 6284539243..32af43852a 100644
--- a/hw/virtio/virtio-mem.c
+++ b/hw/virtio/virtio-mem.c
@@ -1736,7 +1736,7 @@ static bool virtio_mem_rdm_is_populated(const RamDiscardManager *rdm,
 }
 
 struct VirtIOMEMReplayData {
-    void *fn;
+    ReplayRamDiscardState fn;
     void *opaque;
 };
 
@@ -1744,12 +1744,12 @@ static int virtio_mem_rdm_replay_populated_cb(MemoryRegionSection *s, void *arg)
 {
     struct VirtIOMEMReplayData *data = arg;
 
-    return ((ReplayRamPopulate)data->fn)(s, data->opaque);
+    return data->fn(s, data->opaque);
 }
 
 static int virtio_mem_rdm_replay_populated(const RamDiscardManager *rdm,
                                            MemoryRegionSection *s,
-                                           ReplayRamPopulate replay_fn,
+                                           ReplayRamDiscardState replay_fn,
                                            void *opaque)
 {
     const VirtIOMEM *vmem = VIRTIO_MEM(rdm);
@@ -1768,14 +1768,13 @@ static int virtio_mem_rdm_replay_discarded_cb(MemoryRegionSection *s,
 {
     struct VirtIOMEMReplayData *data = arg;
 
-    ((ReplayRamDiscard)data->fn)(s, data->opaque);
-    return 0;
+    return data->fn(s, data->opaque);
 }
 
-static void virtio_mem_rdm_replay_discarded(const RamDiscardManager *rdm,
-                                            MemoryRegionSection *s,
-                                            ReplayRamDiscard replay_fn,
-                                            void *opaque)
+static int virtio_mem_rdm_replay_discarded(const RamDiscardManager *rdm,
+                                           MemoryRegionSection *s,
+                                           ReplayRamDiscardState replay_fn,
+                                           void *opaque)
 {
     const VirtIOMEM *vmem = VIRTIO_MEM(rdm);
     struct VirtIOMEMReplayData data = {
@@ -1784,8 +1783,8 @@ static void virtio_mem_rdm_replay_discarded(const RamDiscardManager *rdm,
     };
 
     g_assert(s->mr == &vmem->memdev->mr);
-    virtio_mem_for_each_unplugged_section(vmem, s, &data,
-                                          virtio_mem_rdm_replay_discarded_cb);
+    return virtio_mem_for_each_unplugged_section(vmem, s, &data,
+                                                 virtio_mem_rdm_replay_discarded_cb);
 }
 
 static void virtio_mem_rdm_register_listener(RamDiscardManager *rdm,
diff --git a/include/exec/memory.h b/include/exec/memory.h
index 7cfbe203f4..563353eab6 100644
--- a/include/exec/memory.h
+++ b/include/exec/memory.h
@@ -566,8 +566,20 @@ static inline void ram_discard_listener_init(RamDiscardListener *rdl,
     rdl->double_discard_supported = double_discard_supported;
 }
 
-typedef int (*ReplayRamPopulate)(MemoryRegionSection *section, void *opaque);
-typedef void (*ReplayRamDiscard)(MemoryRegionSection *section, void *opaque);
+/**
+ * typedef ReplayRamDiscardState:
+ *
+ * The callback handler for #RamDiscardManagerClass.replay_populated/
+ * #RamDiscardManagerClass.replay_discarded to invoke on populated/discarded
+ * parts.
+ *
+ * @section: the #MemoryRegionSection of populated/discarded part
+ * @opaque: pointer to forward to the callback
+ *
+ * Returns 0 on success, or a negative error if failed.
+ */
+typedef int (*ReplayRamDiscardState)(MemoryRegionSection *section,
+                                     void *opaque);
 
 /*
  * RamDiscardManagerClass:
@@ -641,36 +653,38 @@ struct RamDiscardManagerClass {
     /**
      * @replay_populated:
      *
-     * Call the #ReplayRamPopulate callback for all populated parts within the
-     * #MemoryRegionSection via the #RamDiscardManager.
+     * Call the #ReplayRamDiscardState callback for all populated parts within
+     * the #MemoryRegionSection via the #RamDiscardManager.
      *
      * In case any call fails, no further calls are made.
      *
      * @rdm: the #RamDiscardManager
      * @section: the #MemoryRegionSection
-     * @replay_fn: the #ReplayRamPopulate callback
+     * @replay_fn: the #ReplayRamDiscardState callback
      * @opaque: pointer to forward to the callback
      *
      * Returns 0 on success, or a negative error if any notification failed.
      */
     int (*replay_populated)(const RamDiscardManager *rdm,
                             MemoryRegionSection *section,
-                            ReplayRamPopulate replay_fn, void *opaque);
+                            ReplayRamDiscardState replay_fn, void *opaque);
 
     /**
      * @replay_discarded:
      *
-     * Call the #ReplayRamDiscard callback for all discarded parts within the
-     * #MemoryRegionSection via the #RamDiscardManager.
+     * Call the #ReplayRamDiscardState callback for all discarded parts within
+     * the #MemoryRegionSection via the #RamDiscardManager.
      *
      * @rdm: the #RamDiscardManager
      * @section: the #MemoryRegionSection
-     * @replay_fn: the #ReplayRamDiscard callback
+     * @replay_fn: the #ReplayRamDiscardState callback
      * @opaque: pointer to forward to the callback
+     *
+     * Returns 0 on success, or a negative error if any notification failed.
      */
-    void (*replay_discarded)(const RamDiscardManager *rdm,
-                             MemoryRegionSection *section,
-                             ReplayRamDiscard replay_fn, void *opaque);
+    int (*replay_discarded)(const RamDiscardManager *rdm,
+                            MemoryRegionSection *section,
+                            ReplayRamDiscardState replay_fn, void *opaque);
 
     /**
      * @register_listener:
@@ -711,15 +725,41 @@ uint64_t ram_discard_manager_get_min_granularity(const RamDiscardManager *rdm,
 bool ram_discard_manager_is_populated(const RamDiscardManager *rdm,
                                       const MemoryRegionSection *section);
 
+/**
+ * ram_discard_manager_replay_populated:
+ *
+ * A wrapper to call the #RamDiscardManagerClass.replay_populated callback
+ * of the #RamDiscardManager.
+ *
+ * @rdm: the #RamDiscardManager
+ * @section: the #MemoryRegionSection
+ * @replay_fn: the #ReplayRamDiscardState callback
+ * @opaque: pointer to forward to the callback
+ *
+ * Returns 0 on success, or a negative error if any notification failed.
+ */
 int ram_discard_manager_replay_populated(const RamDiscardManager *rdm,
                                          MemoryRegionSection *section,
-                                         ReplayRamPopulate replay_fn,
+                                         ReplayRamDiscardState replay_fn,
                                          void *opaque);
 
-void ram_discard_manager_replay_discarded(const RamDiscardManager *rdm,
-                                          MemoryRegionSection *section,
-                                          ReplayRamDiscard replay_fn,
-                                          void *opaque);
+/**
+ * ram_discard_manager_replay_discarded:
+ *
+ * A wrapper to call the #RamDiscardManagerClass.replay_discarded callback
+ * of the #RamDiscardManager.
+ *
+ * @rdm: the #RamDiscardManager
+ * @section: the #MemoryRegionSection
+ * @replay_fn: the #ReplayRamDiscardState callback
+ * @opaque: pointer to forward to the callback
+ *
+ * Returns 0 on success, or a negative error if any notification failed.
+ */
+int ram_discard_manager_replay_discarded(const RamDiscardManager *rdm,
+                                         MemoryRegionSection *section,
+                                         ReplayRamDiscardState replay_fn,
+                                         void *opaque);
 
 void ram_discard_manager_register_listener(RamDiscardManager *rdm,
                                            RamDiscardListener *rdl,
diff --git a/migration/ram.c b/migration/ram.c
index 0803f85b8a..aaeea04546 100644
--- a/migration/ram.c
+++ b/migration/ram.c
@@ -874,8 +874,8 @@ static inline bool migration_bitmap_clear_dirty(RAMState *rs,
     return ret;
 }
 
-static void dirty_bitmap_clear_section(MemoryRegionSection *section,
-                                       void *opaque)
+static int dirty_bitmap_clear_section(MemoryRegionSection *section,
+                                      void *opaque)
 {
     const hwaddr offset = section->offset_within_region;
     const hwaddr size = int128_get64(section->size);
@@ -894,6 +894,7 @@ static void dirty_bitmap_clear_section(MemoryRegionSection *section,
     }
     *cleared_bits += bitmap_count_one_with_offset(rb->bmap, start, npages);
     bitmap_clear(rb->bmap, start, npages);
+    return 0;
 }
 
 /*
diff --git a/system/memory.c b/system/memory.c
index 35011f731e..8c36ab17b6 100644
--- a/system/memory.c
+++ b/system/memory.c
@@ -2115,7 +2115,7 @@ bool ram_discard_manager_is_populated(const RamDiscardManager *rdm,
 
 int ram_discard_manager_replay_populated(const RamDiscardManager *rdm,
                                          MemoryRegionSection *section,
-                                         ReplayRamPopulate replay_fn,
+                                         ReplayRamDiscardState replay_fn,
                                          void *opaque)
 {
     RamDiscardManagerClass *rdmc = RAM_DISCARD_MANAGER_GET_CLASS(rdm);
@@ -2124,15 +2124,15 @@ int ram_discard_manager_replay_populated(const RamDiscardManager *rdm,
     return rdmc->replay_populated(rdm, section, replay_fn, opaque);
 }
 
-void ram_discard_manager_replay_discarded(const RamDiscardManager *rdm,
-                                          MemoryRegionSection *section,
-                                          ReplayRamDiscard replay_fn,
-                                          void *opaque)
+int ram_discard_manager_replay_discarded(const RamDiscardManager *rdm,
+                                         MemoryRegionSection *section,
+                                         ReplayRamDiscardState replay_fn,
+                                         void *opaque)
 {
     RamDiscardManagerClass *rdmc = RAM_DISCARD_MANAGER_GET_CLASS(rdm);
 
     g_assert(rdmc->replay_discarded);
-    rdmc->replay_discarded(rdm, section, replay_fn, opaque);
+    return rdmc->replay_discarded(rdm, section, replay_fn, opaque);
 }
 
 void ram_discard_manager_register_listener(RamDiscardManager *rdm,
-- 
2.50.1