mirror of
https://github.com/qemu/qemu.git
synced 2025-08-15 22:31:15 +00:00
2fde3fb916
A new field, attributes, was introduced in RAMBlock to link to a RamBlockAttributes object, which centralizes all guest_memfd related information (such as fd and status bitmap) within a RAMBlock. Create and initialize the RamBlockAttributes object upon ram_block_add(). Meanwhile, register the object in the target RAMBlock's MemoryRegion. After that, guest_memfd-backed RAMBlock is associated with the RamDiscardManager interface, and the users can execute RamDiscardManager specific handling. For example, VFIO will register the RamDiscardListener and get notifications when the state_change() helper invokes. As coordinate discarding of RAM with guest_memfd is now supported, only block uncoordinated discard. Tested-by: Alexey Kardashevskiy <aik@amd.com> Reviewed-by: Alexey Kardashevskiy <aik@amd.com> Acked-by: David Hildenbrand <david@redhat.com> Signed-off-by: Chenyi Qiang <chenyi.qiang@intel.com> Link: https://lore.kernel.org/r/20250612082747.51539-6-chenyi.qiang@intel.com Signed-off-by: Peter Xu <peterx@redhat.com>
117 lines
3.7 KiB
C
117 lines
3.7 KiB
C
/*
|
|
* 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"
|
|
#include "system/hostmem.h"
|
|
|
|
#define TYPE_RAM_BLOCK_ATTRIBUTES "ram-block-attributes"
|
|
OBJECT_DECLARE_SIMPLE_TYPE(RamBlockAttributes, RAM_BLOCK_ATTRIBUTES)
|
|
|
|
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;
|
|
RamBlockAttributes *attributes;
|
|
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;
|
|
};
|
|
|
|
struct RamBlockAttributes {
|
|
Object parent;
|
|
|
|
RAMBlock *ram_block;
|
|
|
|
/* 1-setting of the bitmap represents ram is populated (shared) */
|
|
unsigned bitmap_size;
|
|
unsigned long *bitmap;
|
|
|
|
QLIST_HEAD(, RamDiscardListener) rdl_list;
|
|
};
|
|
|
|
RamBlockAttributes *ram_block_attributes_create(RAMBlock *ram_block);
|
|
void ram_block_attributes_destroy(RamBlockAttributes *attr);
|
|
int ram_block_attributes_state_change(RamBlockAttributes *attr, uint64_t offset,
|
|
uint64_t size, bool to_discard);
|
|
|
|
#endif
|