xref: /openbmc/qemu/include/hw/virtio/virtio-mem.h (revision bf616ce4)
1 /*
2  * Virtio MEM device
3  *
4  * Copyright (C) 2020 Red Hat, Inc.
5  *
6  * Authors:
7  *  David Hildenbrand <david@redhat.com>
8  *
9  * This work is licensed under the terms of the GNU GPL, version 2.
10  * See the COPYING file in the top-level directory.
11  */
12 
13 #ifndef HW_VIRTIO_MEM_H
14 #define HW_VIRTIO_MEM_H
15 
16 #include "standard-headers/linux/virtio_mem.h"
17 #include "hw/virtio/virtio.h"
18 #include "qapi/qapi-types-misc.h"
19 #include "sysemu/hostmem.h"
20 #include "qom/object.h"
21 
22 #define TYPE_VIRTIO_MEM "virtio-mem"
23 
24 OBJECT_DECLARE_TYPE(VirtIOMEM, VirtIOMEMClass,
25                     VIRTIO_MEM)
26 
27 #define VIRTIO_MEM_MEMDEV_PROP "memdev"
28 #define VIRTIO_MEM_NODE_PROP "node"
29 #define VIRTIO_MEM_SIZE_PROP "size"
30 #define VIRTIO_MEM_REQUESTED_SIZE_PROP "requested-size"
31 #define VIRTIO_MEM_BLOCK_SIZE_PROP "block-size"
32 #define VIRTIO_MEM_ADDR_PROP "memaddr"
33 #define VIRTIO_MEM_UNPLUGGED_INACCESSIBLE_PROP "unplugged-inaccessible"
34 #define VIRTIO_MEM_EARLY_MIGRATION_PROP "x-early-migration"
35 #define VIRTIO_MEM_PREALLOC_PROP "prealloc"
36 #define VIRTIO_MEM_DYNAMIC_MEMSLOTS_PROP "dynamic-memslots"
37 
38 struct VirtIOMEM {
39     VirtIODevice parent_obj;
40 
41     /* guest -> host request queue */
42     VirtQueue *vq;
43 
44     /* bitmap used to track unplugged memory */
45     int32_t bitmap_size;
46     unsigned long *bitmap;
47 
48     /*
49      * With "dynamic-memslots=on": Device memory region in which we dynamically
50      * map the memslots.
51      */
52     MemoryRegion *mr;
53 
54     /*
55      * With "dynamic-memslots=on": The individual memslots (aliases into the
56      * memory backend).
57      */
58     MemoryRegion *memslots;
59 
60     /* With "dynamic-memslots=on": The total number of memslots. */
61     uint16_t nb_memslots;
62 
63     /*
64      * With "dynamic-memslots=on": Size of one memslot (the size of the
65      * last one can differ).
66      */
67     uint64_t memslot_size;
68 
69     /* Assigned memory backend with the RAM memory region. */
70     HostMemoryBackend *memdev;
71 
72     /* NUMA node */
73     uint32_t node;
74 
75     /* assigned address of the region in guest physical memory */
76     uint64_t addr;
77 
78     /* usable region size (<= region_size) */
79     uint64_t usable_region_size;
80 
81     /* actual size (how much the guest plugged) */
82     uint64_t size;
83 
84     /* requested size */
85     uint64_t requested_size;
86 
87     /* block size and alignment */
88     uint64_t block_size;
89 
90     /*
91      * Whether we indicate VIRTIO_MEM_F_UNPLUGGED_INACCESSIBLE to the guest.
92      * For !x86 targets this will always be "on" and consequently indicate
93      * VIRTIO_MEM_F_UNPLUGGED_INACCESSIBLE.
94      */
95     OnOffAuto unplugged_inaccessible;
96 
97     /* whether to prealloc memory when plugging new blocks */
98     bool prealloc;
99 
100     /*
101      * Whether we migrate properties that are immutable while migration is
102      * active early, before state of other devices and especially, before
103      * migrating any RAM content.
104      */
105     bool early_migration;
106 
107     /*
108      * Whether we dynamically map (multiple, if possible) memslots instead of
109      * statically mapping the whole RAM memory region.
110      */
111     bool dynamic_memslots;
112 
113     /* notifiers to notify when "size" changes */
114     NotifierList size_change_notifiers;
115 
116     /* listeners to notify on plug/unplug activity. */
117     QLIST_HEAD(, RamDiscardListener) rdl_list;
118 };
119 
120 struct VirtIOMEMClass {
121     /* private */
122     VirtIODevice parent;
123 
124     /* public */
125     void (*fill_device_info)(const VirtIOMEM *vmen, VirtioMEMDeviceInfo *vi);
126     MemoryRegion *(*get_memory_region)(VirtIOMEM *vmem, Error **errp);
127     void (*decide_memslots)(VirtIOMEM *vmem, unsigned int limit);
128     unsigned int (*get_memslots)(VirtIOMEM *vmem);
129     void (*add_size_change_notifier)(VirtIOMEM *vmem, Notifier *notifier);
130     void (*remove_size_change_notifier)(VirtIOMEM *vmem, Notifier *notifier);
131     void (*unplug_request_check)(VirtIOMEM *vmem, Error **errp);
132 };
133 
134 #endif
135