1 /* 2 * Declarations for cpu physical memory functions 3 * 4 * Copyright 2011 Red Hat, Inc. and/or its affiliates 5 * 6 * Authors: 7 * Avi Kivity <avi@redhat.com> 8 * 9 * This work is licensed under the terms of the GNU GPL, version 2 or 10 * later. See the COPYING file in the top-level directory. 11 * 12 */ 13 14 /* 15 * This header is for use by exec.c and memory.c ONLY. Do not include it. 16 * The functions declared here will be removed soon. 17 */ 18 19 #ifndef QEMU_EXEC_RAMBLOCK_H 20 #define QEMU_EXEC_RAMBLOCK_H 21 22 #ifndef CONFIG_USER_ONLY 23 #include "cpu-common.h" 24 #include "qemu/rcu.h" 25 #include "exec/ramlist.h" 26 27 struct RAMBlock { 28 struct rcu_head rcu; 29 struct MemoryRegion *mr; 30 uint8_t *host; 31 uint8_t *colo_cache; /* For colo, VM's ram cache */ 32 ram_addr_t offset; 33 ram_addr_t used_length; 34 ram_addr_t max_length; 35 void (*resized)(const char*, uint64_t length, void *host); 36 uint32_t flags; 37 /* Protected by the BQL. */ 38 char idstr[256]; 39 /* RCU-enabled, writes protected by the ramlist lock */ 40 QLIST_ENTRY(RAMBlock) next; 41 QLIST_HEAD(, RAMBlockNotifier) ramblock_notifiers; 42 int fd; 43 uint64_t fd_offset; 44 size_t page_size; 45 /* dirty bitmap used during migration */ 46 unsigned long *bmap; 47 48 /* 49 * Below fields are only used by mapped-ram migration 50 */ 51 /* bitmap of pages present in the migration file */ 52 unsigned long *file_bmap; 53 /* 54 * offset in the file pages belonging to this ramblock are saved, 55 * used only during migration to a file. 56 */ 57 off_t bitmap_offset; 58 uint64_t pages_offset; 59 60 /* bitmap of already received pages in postcopy */ 61 unsigned long *receivedmap; 62 63 /* 64 * bitmap to track already cleared dirty bitmap. When the bit is 65 * set, it means the corresponding memory chunk needs a log-clear. 66 * Set this up to non-NULL to enable the capability to postpone 67 * and split clearing of dirty bitmap on the remote node (e.g., 68 * KVM). The bitmap will be set only when doing global sync. 69 * 70 * It is only used during src side of ram migration, and it is 71 * protected by the global ram_state.bitmap_mutex. 72 * 73 * NOTE: this bitmap is different comparing to the other bitmaps 74 * in that one bit can represent multiple guest pages (which is 75 * decided by the `clear_bmap_shift' variable below). On 76 * destination side, this should always be NULL, and the variable 77 * `clear_bmap_shift' is meaningless. 78 */ 79 unsigned long *clear_bmap; 80 uint8_t clear_bmap_shift; 81 82 /* 83 * RAM block length that corresponds to the used_length on the migration 84 * source (after RAM block sizes were synchronized). Especially, after 85 * starting to run the guest, used_length and postcopy_length can differ. 86 * Used to register/unregister uffd handlers and as the size of the received 87 * bitmap. Receiving any page beyond this length will bail out, as it 88 * could not have been valid on the source. 89 */ 90 ram_addr_t postcopy_length; 91 }; 92 #endif 93 #endif 94