xref: /qemu/include/hw/virtio/virtio-mem.h (revision 513823e7521a09ed7ad1e32e6454bac3b2cbf52d) 
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/resettable.h"
18 #include "hw/virtio/virtio.h"
19 #include "qapi/qapi-types-misc.h"
20 #include "system/hostmem.h"
21 #include "qom/object.h"
22 
23 #define TYPE_VIRTIO_MEM "virtio-mem"
24 
25 OBJECT_DECLARE_TYPE(VirtIOMEM, VirtIOMEMClass,
26                     VIRTIO_MEM)
27 
28 #define TYPE_VIRTIO_MEM_SYSTEM_RESET "virtio-mem-system-reset"
29 
30 OBJECT_DECLARE_SIMPLE_TYPE(VirtioMemSystemReset, VIRTIO_MEM_SYSTEM_RESET)
31 
32 #define VIRTIO_MEM_MEMDEV_PROP "memdev"
33 #define VIRTIO_MEM_NODE_PROP "node"
34 #define VIRTIO_MEM_SIZE_PROP "size"
35 #define VIRTIO_MEM_REQUESTED_SIZE_PROP "requested-size"
36 #define VIRTIO_MEM_BLOCK_SIZE_PROP "block-size"
37 #define VIRTIO_MEM_ADDR_PROP "memaddr"
38 #define VIRTIO_MEM_UNPLUGGED_INACCESSIBLE_PROP "unplugged-inaccessible"
39 #define VIRTIO_MEM_EARLY_MIGRATION_PROP "x-early-migration"
40 #define VIRTIO_MEM_PREALLOC_PROP "prealloc"
41 #define VIRTIO_MEM_DYNAMIC_MEMSLOTS_PROP "dynamic-memslots"
42 
43 struct VirtIOMEM {
44     VirtIODevice parent_obj;
45 
46     /* guest -> host request queue */
47     VirtQueue *vq;
48 
49     /* bitmap used to track unplugged memory */
50     int32_t bitmap_size;
51     unsigned long *bitmap;
52 
53     /*
54      * With "dynamic-memslots=on": Device memory region in which we dynamically
55      * map the memslots.
56      */
57     MemoryRegion *mr;
58 
59     /*
60      * With "dynamic-memslots=on": The individual memslots (aliases into the
61      * memory backend).
62      */
63     MemoryRegion *memslots;
64 
65     /* With "dynamic-memslots=on": The total number of memslots. */
66     uint16_t nb_memslots;
67 
68     /*
69      * With "dynamic-memslots=on": Size of one memslot (the size of the
70      * last one can differ).
71      */
72     uint64_t memslot_size;
73 
74     /* Assigned memory backend with the RAM memory region. */
75     HostMemoryBackend *memdev;
76 
77     /* NUMA node */
78     uint32_t node;
79 
80     /* assigned address of the region in guest physical memory */
81     uint64_t addr;
82 
83     /* usable region size (<= region_size) */
84     uint64_t usable_region_size;
85 
86     /* actual size (how much the guest plugged) */
87     uint64_t size;
88 
89     /* requested size */
90     uint64_t requested_size;
91 
92     /* block size and alignment */
93     uint64_t block_size;
94 
95     /*
96      * Whether we indicate VIRTIO_MEM_F_UNPLUGGED_INACCESSIBLE to the guest.
97      * For !x86 targets this will always be "on" and consequently indicate
98      * VIRTIO_MEM_F_UNPLUGGED_INACCESSIBLE.
99      */
100     OnOffAuto unplugged_inaccessible;
101 
102     /* whether to prealloc memory when plugging new blocks */
103     bool prealloc;
104 
105     /*
106      * Whether we migrate properties that are immutable while migration is
107      * active early, before state of other devices and especially, before
108      * migrating any RAM content.
109      */
110     bool early_migration;
111 
112     /*
113      * Whether we dynamically map (multiple, if possible) memslots instead of
114      * statically mapping the whole RAM memory region.
115      */
116     bool dynamic_memslots;
117 
118     /* notifiers to notify when "size" changes */
119     NotifierList size_change_notifiers;
120 
121     /* listeners to notify on plug/unplug activity. */
122     QLIST_HEAD(, RamDiscardListener) rdl_list;
123 
124     /* Catch system resets -> qemu_devices_reset() only. */
125     VirtioMemSystemReset *system_reset;
126 };
127 
128 struct VirtioMemSystemReset {
129     Object parent;
130 
131     ResettableState reset_state;
132     VirtIOMEM *vmem;
133 };
134 
135 struct VirtIOMEMClass {
136     /* private */
137     VirtIODevice parent;
138 
139     /* public */
140     void (*fill_device_info)(const VirtIOMEM *vmen, VirtioMEMDeviceInfo *vi);
141     MemoryRegion *(*get_memory_region)(VirtIOMEM *vmem, Error **errp);
142     void (*decide_memslots)(VirtIOMEM *vmem, unsigned int limit);
143     unsigned int (*get_memslots)(VirtIOMEM *vmem);
144     void (*add_size_change_notifier)(VirtIOMEM *vmem, Notifier *notifier);
145     void (*remove_size_change_notifier)(VirtIOMEM *vmem, Notifier *notifier);
146     void (*unplug_request_check)(VirtIOMEM *vmem, Error **errp);
147 };
148 
149 #endif
150