[PULL 13/18] system/ram-discard-manager: drop replay from source interface

[Peter Xu <peterx@redhat.com>]

From: Marc-André Lureau <marcandre.lureau@redhat.com>

Remove replay_populated and replay_discarded from RamDiscardSourceClass
now that the RamDiscardManager handles replay iteration internally via
is_populated.

Remove the now-dead replay methods, helpers, and
for_each_populated/discarded_section() from ram-block-attributes, which
was the last source still carrying this code.

Reviewed-by: Peter Xu <peterx@redhat.com>
Acked-by: David Hildenbrand <david@kernel.org>
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Link: https://lore.kernel.org/r/20260604-rdm5-v5-6-5768e6a0943d@redhat.com
Signed-off-by: Peter Xu <peterx@redhat.com>
---
 include/system/ram-discard-manager.h |  52 +++--------
 system/ram-block-attributes.c        | 130 ---------------------------
 2 files changed, 10 insertions(+), 172 deletions(-)

diff --git a/include/system/ram-discard-manager.h b/include/system/ram-discard-manager.h
index b188e09a30..b5dbcb4a82 100644
--- a/include/system/ram-discard-manager.h
+++ b/include/system/ram-discard-manager.h
@@ -77,8 +77,8 @@ static inline void ram_discard_listener_init(RamDiscardListener *rdl,
 /**
  * typedef ReplayRamDiscardState:
  *
- * The callback handler for #RamDiscardSourceClass.replay_populated/
- * #RamDiscardSourceClass.replay_discarded to invoke on populated/discarded
+ * The callback handler used by ram_discard_manager_replay_populated() and
+ * ram_discard_manager_replay_discarded() to invoke on populated/discarded
  * parts.
  *
  * @section: the #MemoryRegionSection of populated/discarded part
@@ -134,42 +134,6 @@ struct RamDiscardSourceClass {
      */
     bool (*is_populated)(const RamDiscardSource *rds,
                          const MemoryRegionSection *section);
-
-    /**
-     * @replay_populated:
-     *
-     * Call the #ReplayRamDiscardState callback for all populated parts within
-     * the #MemoryRegionSection via the #RamDiscardSource.
-     *
-     * In case any call fails, no further calls are made.
-     *
-     * @rds: the #RamDiscardSource
-     * @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 (*replay_populated)(const RamDiscardSource *rds,
-                            const MemoryRegionSection *section,
-                            ReplayRamDiscardState replay_fn, void *opaque);
-
-    /**
-     * @replay_discarded:
-     *
-     * Call the #ReplayRamDiscardState callback for all discarded parts within
-     * the #MemoryRegionSection via the #RamDiscardSource.
-     *
-     * @rds: the #RamDiscardSource
-     * @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 (*replay_discarded)(const RamDiscardSource *rds,
-                            const MemoryRegionSection *section,
-                            ReplayRamDiscardState replay_fn, void *opaque);
 };
 
 /**
@@ -226,8 +190,10 @@ bool ram_discard_manager_is_populated(const RamDiscardManager *rdm,
 /**
  * ram_discard_manager_replay_populated:
  *
- * A wrapper to call the #RamDiscardSourceClass.replay_populated callback
- * of the #RamDiscardSource sources.
+ * Iterate the given #MemoryRegionSection at minimum granularity, calling
+ * #RamDiscardSourceClass.is_populated for each chunk, and invoke @replay_fn
+ * for each contiguous populated range. In case any call fails, no further
+ * calls are made.
  *
  * @rdm: the #RamDiscardManager
  * @section: the #MemoryRegionSection
@@ -244,8 +210,10 @@ int ram_discard_manager_replay_populated(const RamDiscardManager *rdm,
 /**
  * ram_discard_manager_replay_discarded:
  *
- * A wrapper to call the #RamDiscardSourceClass.replay_discarded callback
- * of the #RamDiscardSource sources.
+ * Iterate the given #MemoryRegionSection at minimum granularity, calling
+ * #RamDiscardSourceClass.is_populated for each chunk, and invoke @replay_fn
+ * for each contiguous discarded range. In case any call fails, no further
+ * calls are made.
  *
  * @rdm: the #RamDiscardManager
  * @section: the #MemoryRegionSection
diff --git a/system/ram-block-attributes.c b/system/ram-block-attributes.c
index 79c7e97d9a..718c7075ce 100644
--- a/system/ram-block-attributes.c
+++ b/system/ram-block-attributes.c
@@ -32,106 +32,6 @@ ram_block_attributes_get_block_size(void)
     return qemu_real_host_page_size();
 }
 
-typedef int (*ram_block_attributes_section_cb)(MemoryRegionSection *s,
-                                               void *arg);
-
-static int
-ram_block_attributes_for_each_populated_section(const RamBlockAttributes *attr,
-                                                const MemoryRegionSection *section,
-                                                void *arg,
-                                                ram_block_attributes_section_cb cb)
-{
-    unsigned long first_bit, last_bit;
-    uint64_t offset, size;
-    const size_t block_size = ram_block_attributes_get_block_size();
-    int ret = 0;
-
-    first_bit = section->offset_within_region / block_size;
-    first_bit = find_next_bit(attr->bitmap, attr->bitmap_size,
-                              first_bit);
-
-    while (first_bit < attr->bitmap_size) {
-        MemoryRegionSection tmp = *section;
-
-        offset = first_bit * block_size;
-        last_bit = find_next_zero_bit(attr->bitmap, attr->bitmap_size,
-                                      first_bit + 1) - 1;
-        size = (last_bit - first_bit + 1) * block_size;
-
-        if (!memory_region_section_intersect_range(&tmp, offset, size)) {
-            break;
-        }
-
-        ret = cb(&tmp, arg);
-        if (ret) {
-            error_report("%s: Failed to notify RAM discard listener: %s",
-                         __func__, strerror(-ret));
-            break;
-        }
-
-        first_bit = find_next_bit(attr->bitmap, attr->bitmap_size,
-                                  last_bit + 2);
-    }
-
-    return ret;
-}
-
-static int
-ram_block_attributes_for_each_discarded_section(const RamBlockAttributes *attr,
-                                                const MemoryRegionSection *section,
-                                                void *arg,
-                                                ram_block_attributes_section_cb cb)
-{
-    unsigned long first_bit, last_bit;
-    uint64_t offset, size;
-    const size_t block_size = ram_block_attributes_get_block_size();
-    int ret = 0;
-
-    first_bit = section->offset_within_region / block_size;
-    first_bit = find_next_zero_bit(attr->bitmap, attr->bitmap_size,
-                                   first_bit);
-
-    while (first_bit < attr->bitmap_size) {
-        MemoryRegionSection tmp = *section;
-
-        offset = first_bit * block_size;
-        last_bit = find_next_bit(attr->bitmap, attr->bitmap_size,
-                                 first_bit + 1) - 1;
-        size = (last_bit - first_bit + 1) * block_size;
-
-        if (!memory_region_section_intersect_range(&tmp, offset, size)) {
-            break;
-        }
-
-        ret = cb(&tmp, arg);
-        if (ret) {
-            error_report("%s: Failed to notify RAM discard listener: %s",
-                         __func__, strerror(-ret));
-            break;
-        }
-
-        first_bit = find_next_zero_bit(attr->bitmap,
-                                       attr->bitmap_size,
-                                       last_bit + 2);
-    }
-
-    return ret;
-}
-
-
-typedef struct RamBlockAttributesReplayData {
-    ReplayRamDiscardState fn;
-    void *opaque;
-} RamBlockAttributesReplayData;
-
-static int ram_block_attributes_rds_replay_cb(MemoryRegionSection *section,
-                                              void *arg)
-{
-    RamBlockAttributesReplayData *data = arg;
-
-    return data->fn(section, data->opaque);
-}
-
 /* RamDiscardSource interface implementation */
 static uint64_t
 ram_block_attributes_rds_get_min_granularity(const RamDiscardSource *rds,
@@ -159,34 +59,6 @@ ram_block_attributes_rds_is_populated(const RamDiscardSource *rds,
     return first_discarded_bit > last_bit;
 }
 
-static int
-ram_block_attributes_rds_replay_populated(const RamDiscardSource *rds,
-                                          const MemoryRegionSection *section,
-                                          ReplayRamDiscardState replay_fn,
-                                          void *opaque)
-{
-    RamBlockAttributes *attr = RAM_BLOCK_ATTRIBUTES(rds);
-    RamBlockAttributesReplayData data = { .fn = replay_fn, .opaque = opaque };
-
-    g_assert(section->mr == attr->ram_block->mr);
-    return ram_block_attributes_for_each_populated_section(attr, section, &data,
-        ram_block_attributes_rds_replay_cb);
-}
-
-static int
-ram_block_attributes_rds_replay_discarded(const RamDiscardSource *rds,
-                                          const MemoryRegionSection *section,
-                                          ReplayRamDiscardState replay_fn,
-                                          void *opaque)
-{
-    RamBlockAttributes *attr = RAM_BLOCK_ATTRIBUTES(rds);
-    RamBlockAttributesReplayData data = { .fn = replay_fn, .opaque = opaque };
-
-    g_assert(section->mr == attr->ram_block->mr);
-    return ram_block_attributes_for_each_discarded_section(attr, section, &data,
-        ram_block_attributes_rds_replay_cb);
-}
-
 static bool
 ram_block_attributes_is_valid_range(RamBlockAttributes *attr, uint64_t offset,
                                     uint64_t size)
@@ -346,6 +218,4 @@ static void ram_block_attributes_class_init(ObjectClass *klass,
 
     rdsc->get_min_granularity = ram_block_attributes_rds_get_min_granularity;
     rdsc->is_populated = ram_block_attributes_rds_is_populated;
-    rdsc->replay_populated = ram_block_attributes_rds_replay_populated;
-    rdsc->replay_discarded = ram_block_attributes_rds_replay_discarded;
 }
-- 
2.54.0