Merge tag 'migration-staging-pull-request' of https://gitlab.com/peterx/qemu into staging

Migration / Memory pull

- Yanfei's optimization to skip log_clear during completion
- Fabiano's cleanup to remove leftover migration-helpers.c file
- Juraj's vnc fix on display pause after migration
- Jaehoon's cpr test fix on possible race of server establishment
- Chenyi's initial support on vfio enablement for guest-memfd

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* tag 'migration-staging-pull-request' of https://gitlab.com/peterx/qemu:
  physmem: Support coordinated discarding of RAM with guest_memfd
  ram-block-attributes: Introduce RamBlockAttributes to manage RAMBlock with guest_memfd
  memory: Unify the definiton of ReplayRamPopulate() and ReplayRamDiscard()
  memory: Change memory_region_set_ram_discard_manager() to return the result
  memory: Export a helper to get intersection of a MemoryRegionSection with a given range
  migration: Don't sync volatile memory after migration completes
  tests/migration: Setup pre-listened cpr.sock to remove race-condition.
  migration: Support fd-based socket address in cpr_transfer_input
  ui/vnc: Update display update interval when VM state changes to RUNNING
  tests/qtest: Remove migration-helpers.c
  migration/ram: avoid to do log clear in the last round

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>

1 files changed, 444 insertions, 0 deletions

diff --git a/system/ram-block-attributes.c b/system/ram-block-attributes.c
new file mode 100644
index 0000000000..68e8a02703
--- /dev/null
+++ b/system/ram-block-attributes.c
@@ -0,0 +1,444 @@
+/*
+ * QEMU ram block attributes
+ *
+ * Copyright Intel
+ *
+ * Author:
+ *      Chenyi Qiang <chenyi.qiang@intel.com>
+ *
+ * SPDX-License-Identifier: GPL-2.0-or-later
+ */
+
+#include "qemu/osdep.h"
+#include "qemu/error-report.h"
+#include "system/ramblock.h"
+#include "trace.h"
+
+OBJECT_DEFINE_SIMPLE_TYPE_WITH_INTERFACES(RamBlockAttributes,
+                                          ram_block_attributes,
+                                          RAM_BLOCK_ATTRIBUTES,
+                                          OBJECT,
+                                          { TYPE_RAM_DISCARD_MANAGER },
+                                          { })
+
+static size_t
+ram_block_attributes_get_block_size(const RamBlockAttributes *attr)
+{
+    /*
+     * Because page conversion could be manipulated in the size of at least 4K
+     * or 4K aligned, Use the host page size as the granularity to track the
+     * memory attribute.
+     */
+    g_assert(attr && attr->ram_block);
+    g_assert(attr->ram_block->page_size == qemu_real_host_page_size());
+    return attr->ram_block->page_size;
+}
+
+
+static bool
+ram_block_attributes_rdm_is_populated(const RamDiscardManager *rdm,
+                                      const MemoryRegionSection *section)
+{
+    const RamBlockAttributes *attr = RAM_BLOCK_ATTRIBUTES(rdm);
+    const size_t block_size = ram_block_attributes_get_block_size(attr);
+    const uint64_t first_bit = section->offset_within_region / block_size;
+    const uint64_t last_bit =
+        first_bit + int128_get64(section->size) / block_size - 1;
+    unsigned long first_discarded_bit;
+
+    first_discarded_bit = find_next_zero_bit(attr->bitmap, last_bit + 1,
+                                           first_bit);
+    return first_discarded_bit > last_bit;
+}
+
+typedef int (*ram_block_attributes_section_cb)(MemoryRegionSection *s,
+                                               void *arg);
+
+static int
+ram_block_attributes_notify_populate_cb(MemoryRegionSection *section,
+                                        void *arg)
+{
+    RamDiscardListener *rdl = arg;
+
+    return rdl->notify_populate(rdl, section);
+}
+
+static int
+ram_block_attributes_notify_discard_cb(MemoryRegionSection *section,
+                                       void *arg)
+{
+    RamDiscardListener *rdl = arg;
+
+    rdl->notify_discard(rdl, section);
+    return 0;
+}
+
+static int
+ram_block_attributes_for_each_populated_section(const RamBlockAttributes *attr,
+                                                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(attr);
+    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,
+                                                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(attr);
+    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;
+}
+
+static uint64_t
+ram_block_attributes_rdm_get_min_granularity(const RamDiscardManager *rdm,
+                                             const MemoryRegion *mr)
+{
+    const RamBlockAttributes *attr = RAM_BLOCK_ATTRIBUTES(rdm);
+
+    g_assert(mr == attr->ram_block->mr);
+    return ram_block_attributes_get_block_size(attr);
+}
+
+static void
+ram_block_attributes_rdm_register_listener(RamDiscardManager *rdm,
+                                           RamDiscardListener *rdl,
+                                           MemoryRegionSection *section)
+{
+    RamBlockAttributes *attr = RAM_BLOCK_ATTRIBUTES(rdm);
+    int ret;
+
+    g_assert(section->mr == attr->ram_block->mr);
+    rdl->section = memory_region_section_new_copy(section);
+
+    QLIST_INSERT_HEAD(&attr->rdl_list, rdl, next);
+
+    ret = ram_block_attributes_for_each_populated_section(attr, section, rdl,
+                                    ram_block_attributes_notify_populate_cb);
+    if (ret) {
+        error_report("%s: Failed to register RAM discard listener: %s",
+                     __func__, strerror(-ret));
+        exit(1);
+    }
+}
+
+static void
+ram_block_attributes_rdm_unregister_listener(RamDiscardManager *rdm,
+                                             RamDiscardListener *rdl)
+{
+    RamBlockAttributes *attr = RAM_BLOCK_ATTRIBUTES(rdm);
+    int ret;
+
+    g_assert(rdl->section);
+    g_assert(rdl->section->mr == attr->ram_block->mr);
+
+    if (rdl->double_discard_supported) {
+        rdl->notify_discard(rdl, rdl->section);
+    } else {
+        ret = ram_block_attributes_for_each_populated_section(attr,
+                rdl->section, rdl, ram_block_attributes_notify_discard_cb);
+        if (ret) {
+            error_report("%s: Failed to unregister RAM discard listener: %s",
+                         __func__, strerror(-ret));
+            exit(1);
+        }
+    }
+
+    memory_region_section_free_copy(rdl->section);
+    rdl->section = NULL;
+    QLIST_REMOVE(rdl, next);
+}
+
+typedef struct RamBlockAttributesReplayData {
+    ReplayRamDiscardState fn;
+    void *opaque;
+} RamBlockAttributesReplayData;
+
+static int ram_block_attributes_rdm_replay_cb(MemoryRegionSection *section,
+                                              void *arg)
+{
+    RamBlockAttributesReplayData *data = arg;
+
+    return data->fn(section, data->opaque);
+}
+
+static int
+ram_block_attributes_rdm_replay_populated(const RamDiscardManager *rdm,
+                                          MemoryRegionSection *section,
+                                          ReplayRamDiscardState replay_fn,
+                                          void *opaque)
+{
+    RamBlockAttributes *attr = RAM_BLOCK_ATTRIBUTES(rdm);
+    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_rdm_replay_cb);
+}
+
+static int
+ram_block_attributes_rdm_replay_discarded(const RamDiscardManager *rdm,
+                                          MemoryRegionSection *section,
+                                          ReplayRamDiscardState replay_fn,
+                                          void *opaque)
+{
+    RamBlockAttributes *attr = RAM_BLOCK_ATTRIBUTES(rdm);
+    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_rdm_replay_cb);
+}
+
+static bool
+ram_block_attributes_is_valid_range(RamBlockAttributes *attr, uint64_t offset,
+                                    uint64_t size)
+{
+    MemoryRegion *mr = attr->ram_block->mr;
+
+    g_assert(mr);
+
+    uint64_t region_size = memory_region_size(mr);
+    const size_t block_size = ram_block_attributes_get_block_size(attr);
+
+    if (!QEMU_IS_ALIGNED(offset, block_size) ||
+        !QEMU_IS_ALIGNED(size, block_size)) {
+        return false;
+    }
+    if (offset + size <= offset) {
+        return false;
+    }
+    if (offset + size > region_size) {
+        return false;
+    }
+    return true;
+}
+
+static void ram_block_attributes_notify_discard(RamBlockAttributes *attr,
+                                                uint64_t offset,
+                                                uint64_t size)
+{
+    RamDiscardListener *rdl;
+
+    QLIST_FOREACH(rdl, &attr->rdl_list, next) {
+        MemoryRegionSection tmp = *rdl->section;
+
+        if (!memory_region_section_intersect_range(&tmp, offset, size)) {
+            continue;
+        }
+        rdl->notify_discard(rdl, &tmp);
+    }
+}
+
+static int
+ram_block_attributes_notify_populate(RamBlockAttributes *attr,
+                                     uint64_t offset, uint64_t size)
+{
+    RamDiscardListener *rdl;
+    int ret = 0;
+
+    QLIST_FOREACH(rdl, &attr->rdl_list, next) {
+        MemoryRegionSection tmp = *rdl->section;
+
+        if (!memory_region_section_intersect_range(&tmp, offset, size)) {
+            continue;
+        }
+        ret = rdl->notify_populate(rdl, &tmp);
+        if (ret) {
+            break;
+        }
+    }
+
+    return ret;
+}
+
+int ram_block_attributes_state_change(RamBlockAttributes *attr,
+                                      uint64_t offset, uint64_t size,
+                                      bool to_discard)
+{
+    const size_t block_size = ram_block_attributes_get_block_size(attr);
+    const unsigned long first_bit = offset / block_size;
+    const unsigned long nbits = size / block_size;
+    const unsigned long last_bit = first_bit + nbits - 1;
+    const bool is_discarded = find_next_bit(attr->bitmap, attr->bitmap_size,
+                                            first_bit) > last_bit;
+    const bool is_populated = find_next_zero_bit(attr->bitmap,
+                                attr->bitmap_size, first_bit) > last_bit;
+    unsigned long bit;
+    int ret = 0;
+
+    if (!ram_block_attributes_is_valid_range(attr, offset, size)) {
+        error_report("%s, invalid range: offset 0x%" PRIx64 ", size "
+                     "0x%" PRIx64, __func__, offset, size);
+        return -EINVAL;
+    }
+
+    trace_ram_block_attributes_state_change(offset, size,
+                                            is_discarded ? "discarded" :
+                                            is_populated ? "populated" :
+                                            "mixture",
+                                            to_discard ? "discarded" :
+                                            "populated");
+    if (to_discard) {
+        if (is_discarded) {
+            /* Already private */
+        } else if (is_populated) {
+            /* Completely shared */
+            bitmap_clear(attr->bitmap, first_bit, nbits);
+            ram_block_attributes_notify_discard(attr, offset, size);
+        } else {
+            /* Unexpected mixture: process individual blocks */
+            for (bit = first_bit; bit < first_bit + nbits; bit++) {
+                if (!test_bit(bit, attr->bitmap)) {
+                    continue;
+                }
+                clear_bit(bit, attr->bitmap);
+                ram_block_attributes_notify_discard(attr, bit * block_size,
+                                                    block_size);
+            }
+        }
+    } else {
+        if (is_populated) {
+            /* Already shared */
+        } else if (is_discarded) {
+            /* Completely private */
+            bitmap_set(attr->bitmap, first_bit, nbits);
+            ret = ram_block_attributes_notify_populate(attr, offset, size);
+        } else {
+            /* Unexpected mixture: process individual blocks */
+            for (bit = first_bit; bit < first_bit + nbits; bit++) {
+                if (test_bit(bit, attr->bitmap)) {
+                    continue;
+                }
+                set_bit(bit, attr->bitmap);
+                ret = ram_block_attributes_notify_populate(attr,
+                                                           bit * block_size,
+                                                           block_size);
+                if (ret) {
+                    break;
+                }
+            }
+        }
+    }
+
+    return ret;
+}
+
+RamBlockAttributes *ram_block_attributes_create(RAMBlock *ram_block)
+{
+    const int block_size  = qemu_real_host_page_size();
+    RamBlockAttributes *attr;
+    MemoryRegion *mr = ram_block->mr;
+
+    attr = RAM_BLOCK_ATTRIBUTES(object_new(TYPE_RAM_BLOCK_ATTRIBUTES));
+
+    attr->ram_block = ram_block;
+    if (memory_region_set_ram_discard_manager(mr, RAM_DISCARD_MANAGER(attr))) {
+        object_unref(OBJECT(attr));
+        return NULL;
+    }
+    attr->bitmap_size =
+        ROUND_UP(int128_get64(mr->size), block_size) / block_size;
+    attr->bitmap = bitmap_new(attr->bitmap_size);
+
+    return attr;
+}
+
+void ram_block_attributes_destroy(RamBlockAttributes *attr)
+{
+    g_assert(attr);
+
+    g_free(attr->bitmap);
+    memory_region_set_ram_discard_manager(attr->ram_block->mr, NULL);
+    object_unref(OBJECT(attr));
+}
+
+static void ram_block_attributes_init(Object *obj)
+{
+    RamBlockAttributes *attr = RAM_BLOCK_ATTRIBUTES(obj);
+
+    QLIST_INIT(&attr->rdl_list);
+}
+
+static void ram_block_attributes_finalize(Object *obj)
+{
+}
+
+static void ram_block_attributes_class_init(ObjectClass *klass,
+                                            const void *data)
+{
+    RamDiscardManagerClass *rdmc = RAM_DISCARD_MANAGER_CLASS(klass);
+
+    rdmc->get_min_granularity = ram_block_attributes_rdm_get_min_granularity;
+    rdmc->register_listener = ram_block_attributes_rdm_register_listener;
+    rdmc->unregister_listener = ram_block_attributes_rdm_unregister_listener;
+    rdmc->is_populated = ram_block_attributes_rdm_is_populated;
+    rdmc->replay_populated = ram_block_attributes_rdm_replay_populated;
+    rdmc->replay_discarded = ram_block_attributes_rdm_replay_discarded;
+}