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13#include "qemu/osdep.h"
14#include "qapi/error.h"
15#include "qemu/error-report.h"
16#include "qemu/module.h"
17#include "sysemu/hostmem.h"
18#include "sysemu/sysemu.h"
19#include "qom/object_interfaces.h"
20#include "qom/object.h"
21
22OBJECT_DECLARE_SIMPLE_TYPE(HostMemoryBackendFile, MEMORY_BACKEND_FILE)
23
24
25struct HostMemoryBackendFile {
26 HostMemoryBackend parent_obj;
27
28 char *mem_path;
29 uint64_t align;
30 bool discard_data;
31 bool is_pmem;
32 bool readonly;
33};
34
35static void
36file_backend_memory_alloc(HostMemoryBackend *backend, Error **errp)
37{
38#ifndef CONFIG_POSIX
39 error_setg(errp, "backend '%s' not supported on this host",
40 object_get_typename(OBJECT(backend)));
41#else
42 HostMemoryBackendFile *fb = MEMORY_BACKEND_FILE(backend);
43 gchar *name;
44
45 if (!backend->size) {
46 error_setg(errp, "can't create backend with size 0");
47 return;
48 }
49 if (!fb->mem_path) {
50 error_setg(errp, "mem-path property not set");
51 return;
52 }
53
54 name = host_memory_backend_get_name(backend);
55 memory_region_init_ram_from_file(&backend->mr, OBJECT(backend),
56 name,
57 backend->size, fb->align,
58 (backend->share ? RAM_SHARED : 0) |
59 (fb->is_pmem ? RAM_PMEM : 0),
60 fb->mem_path, fb->readonly, errp);
61 g_free(name);
62#endif
63}
64
65static char *get_mem_path(Object *o, Error **errp)
66{
67 HostMemoryBackendFile *fb = MEMORY_BACKEND_FILE(o);
68
69 return g_strdup(fb->mem_path);
70}
71
72static void set_mem_path(Object *o, const char *str, Error **errp)
73{
74 HostMemoryBackend *backend = MEMORY_BACKEND(o);
75 HostMemoryBackendFile *fb = MEMORY_BACKEND_FILE(o);
76
77 if (host_memory_backend_mr_inited(backend)) {
78 error_setg(errp, "cannot change property 'mem-path' of %s",
79 object_get_typename(o));
80 return;
81 }
82 g_free(fb->mem_path);
83 fb->mem_path = g_strdup(str);
84}
85
86static bool file_memory_backend_get_discard_data(Object *o, Error **errp)
87{
88 return MEMORY_BACKEND_FILE(o)->discard_data;
89}
90
91static void file_memory_backend_set_discard_data(Object *o, bool value,
92 Error **errp)
93{
94 MEMORY_BACKEND_FILE(o)->discard_data = value;
95}
96
97static void file_memory_backend_get_align(Object *o, Visitor *v,
98 const char *name, void *opaque,
99 Error **errp)
100{
101 HostMemoryBackendFile *fb = MEMORY_BACKEND_FILE(o);
102 uint64_t val = fb->align;
103
104 visit_type_size(v, name, &val, errp);
105}
106
107static void file_memory_backend_set_align(Object *o, Visitor *v,
108 const char *name, void *opaque,
109 Error **errp)
110{
111 HostMemoryBackend *backend = MEMORY_BACKEND(o);
112 HostMemoryBackendFile *fb = MEMORY_BACKEND_FILE(o);
113 uint64_t val;
114
115 if (host_memory_backend_mr_inited(backend)) {
116 error_setg(errp, "cannot change property '%s' of %s", name,
117 object_get_typename(o));
118 return;
119 }
120
121 if (!visit_type_size(v, name, &val, errp)) {
122 return;
123 }
124 fb->align = val;
125}
126
127#ifdef CONFIG_LIBPMEM
128static bool file_memory_backend_get_pmem(Object *o, Error **errp)
129{
130 return MEMORY_BACKEND_FILE(o)->is_pmem;
131}
132
133static void file_memory_backend_set_pmem(Object *o, bool value, Error **errp)
134{
135 HostMemoryBackend *backend = MEMORY_BACKEND(o);
136 HostMemoryBackendFile *fb = MEMORY_BACKEND_FILE(o);
137
138 if (host_memory_backend_mr_inited(backend)) {
139 error_setg(errp, "cannot change property 'pmem' of %s.",
140 object_get_typename(o));
141 return;
142 }
143
144 fb->is_pmem = value;
145}
146#endif
147
148static bool file_memory_backend_get_readonly(Object *obj, Error **errp)
149{
150 HostMemoryBackendFile *fb = MEMORY_BACKEND_FILE(obj);
151
152 return fb->readonly;
153}
154
155static void file_memory_backend_set_readonly(Object *obj, bool value,
156 Error **errp)
157{
158 HostMemoryBackend *backend = MEMORY_BACKEND(obj);
159 HostMemoryBackendFile *fb = MEMORY_BACKEND_FILE(obj);
160
161 if (host_memory_backend_mr_inited(backend)) {
162 error_setg(errp, "cannot change property 'readonly' of %s.",
163 object_get_typename(obj));
164 return;
165 }
166
167 fb->readonly = value;
168}
169
170static void file_backend_unparent(Object *obj)
171{
172 HostMemoryBackend *backend = MEMORY_BACKEND(obj);
173 HostMemoryBackendFile *fb = MEMORY_BACKEND_FILE(obj);
174
175 if (host_memory_backend_mr_inited(backend) && fb->discard_data) {
176 void *ptr = memory_region_get_ram_ptr(&backend->mr);
177 uint64_t sz = memory_region_size(&backend->mr);
178
179 qemu_madvise(ptr, sz, QEMU_MADV_REMOVE);
180 }
181}
182
183static void
184file_backend_class_init(ObjectClass *oc, void *data)
185{
186 HostMemoryBackendClass *bc = MEMORY_BACKEND_CLASS(oc);
187
188 bc->alloc = file_backend_memory_alloc;
189 oc->unparent = file_backend_unparent;
190
191 object_class_property_add_bool(oc, "discard-data",
192 file_memory_backend_get_discard_data, file_memory_backend_set_discard_data);
193 object_class_property_add_str(oc, "mem-path",
194 get_mem_path, set_mem_path);
195 object_class_property_add(oc, "align", "int",
196 file_memory_backend_get_align,
197 file_memory_backend_set_align,
198 NULL, NULL);
199#ifdef CONFIG_LIBPMEM
200 object_class_property_add_bool(oc, "pmem",
201 file_memory_backend_get_pmem, file_memory_backend_set_pmem);
202#endif
203 object_class_property_add_bool(oc, "readonly",
204 file_memory_backend_get_readonly,
205 file_memory_backend_set_readonly);
206}
207
208static void file_backend_instance_finalize(Object *o)
209{
210 HostMemoryBackendFile *fb = MEMORY_BACKEND_FILE(o);
211
212 g_free(fb->mem_path);
213}
214
215static const TypeInfo file_backend_info = {
216 .name = TYPE_MEMORY_BACKEND_FILE,
217 .parent = TYPE_MEMORY_BACKEND,
218 .class_init = file_backend_class_init,
219 .instance_finalize = file_backend_instance_finalize,
220 .instance_size = sizeof(HostMemoryBackendFile),
221};
222
223static void register_types(void)
224{
225 type_register_static(&file_backend_info);
226}
227
228type_init(register_types);
229
