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-rw-r--r--include/system/ramblock.h94
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diff --git a/include/system/ramblock.h b/include/system/ramblock.h
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+/*
+ * Declarations for cpu physical memory functions
+ *
+ * Copyright 2011 Red Hat, Inc. and/or its affiliates
+ *
+ * Authors:
+ *  Avi Kivity <avi@redhat.com>
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2 or
+ * later.  See the COPYING file in the top-level directory.
+ *
+ */
+
+/*
+ * This header is for use by exec.c and memory.c ONLY.  Do not include it.
+ * The functions declared here will be removed soon.
+ */
+
+#ifndef SYSTEM_RAMBLOCK_H
+#define SYSTEM_RAMBLOCK_H
+
+#include "exec/cpu-common.h"
+#include "qemu/rcu.h"
+#include "exec/ramlist.h"
+
+struct RAMBlock {
+    struct rcu_head rcu;
+    struct MemoryRegion *mr;
+    uint8_t *host;
+    uint8_t *colo_cache; /* For colo, VM's ram cache */
+    ram_addr_t offset;
+    ram_addr_t used_length;
+    ram_addr_t max_length;
+    void (*resized)(const char*, uint64_t length, void *host);
+    uint32_t flags;
+    /* Protected by the BQL.  */
+    char idstr[256];
+    /* RCU-enabled, writes protected by the ramlist lock */
+    QLIST_ENTRY(RAMBlock) next;
+    QLIST_HEAD(, RAMBlockNotifier) ramblock_notifiers;
+    Error *cpr_blocker;
+    int fd;
+    uint64_t fd_offset;
+    int guest_memfd;
+    size_t page_size;
+    /* dirty bitmap used during migration */
+    unsigned long *bmap;
+
+    /*
+     * Below fields are only used by mapped-ram migration
+     */
+    /* bitmap of pages present in the migration file */
+    unsigned long *file_bmap;
+    /*
+     * offset in the file pages belonging to this ramblock are saved,
+     * used only during migration to a file.
+     */
+    off_t bitmap_offset;
+    uint64_t pages_offset;
+
+    /* Bitmap of already received pages.  Only used on destination side. */
+    unsigned long *receivedmap;
+
+    /*
+     * bitmap to track already cleared dirty bitmap.  When the bit is
+     * set, it means the corresponding memory chunk needs a log-clear.
+     * Set this up to non-NULL to enable the capability to postpone
+     * and split clearing of dirty bitmap on the remote node (e.g.,
+     * KVM).  The bitmap will be set only when doing global sync.
+     *
+     * It is only used during src side of ram migration, and it is
+     * protected by the global ram_state.bitmap_mutex.
+     *
+     * NOTE: this bitmap is different comparing to the other bitmaps
+     * in that one bit can represent multiple guest pages (which is
+     * decided by the `clear_bmap_shift' variable below).  On
+     * destination side, this should always be NULL, and the variable
+     * `clear_bmap_shift' is meaningless.
+     */
+    unsigned long *clear_bmap;
+    uint8_t clear_bmap_shift;
+
+    /*
+     * RAM block length that corresponds to the used_length on the migration
+     * source (after RAM block sizes were synchronized). Especially, after
+     * starting to run the guest, used_length and postcopy_length can differ.
+     * Used to register/unregister uffd handlers and as the size of the received
+     * bitmap. Receiving any page beyond this length will bail out, as it
+     * could not have been valid on the source.
+     */
+    ram_addr_t postcopy_length;
+};
+
+#endif