xref: /openbmc/qemu/hw/mem/memory-device.c (revision a322714248b9e8dffe6a2bb379ffd5d59b394bb7)
1 /*
2  * Memory Device Interface
3  *
4  * Copyright ProfitBricks GmbH 2012
5  * Copyright (C) 2014 Red Hat Inc
6  * Copyright (c) 2018 Red Hat Inc
7  *
8  * This work is licensed under the terms of the GNU GPL, version 2 or later.
9  * See the COPYING file in the top-level directory.
10  */
11 
12 #include "qemu/osdep.h"
13 #include "hw/mem/memory-device.h"
14 #include "hw/qdev.h"
15 #include "qapi/error.h"
16 #include "hw/boards.h"
17 #include "qemu/range.h"
18 #include "hw/virtio/vhost.h"
19 #include "sysemu/kvm.h"
20 
21 static gint memory_device_addr_sort(gconstpointer a, gconstpointer b)
22 {
23     const MemoryDeviceState *md_a = MEMORY_DEVICE(a);
24     const MemoryDeviceState *md_b = MEMORY_DEVICE(b);
25     const MemoryDeviceClass *mdc_a = MEMORY_DEVICE_GET_CLASS(a);
26     const MemoryDeviceClass *mdc_b = MEMORY_DEVICE_GET_CLASS(b);
27     const uint64_t addr_a = mdc_a->get_addr(md_a);
28     const uint64_t addr_b = mdc_b->get_addr(md_b);
29 
30     if (addr_a > addr_b) {
31         return 1;
32     } else if (addr_a < addr_b) {
33         return -1;
34     }
35     return 0;
36 }
37 
38 static int memory_device_build_list(Object *obj, void *opaque)
39 {
40     GSList **list = opaque;
41 
42     if (object_dynamic_cast(obj, TYPE_MEMORY_DEVICE)) {
43         DeviceState *dev = DEVICE(obj);
44         if (dev->realized) { /* only realized memory devices matter */
45             *list = g_slist_insert_sorted(*list, dev, memory_device_addr_sort);
46         }
47     }
48 
49     object_child_foreach(obj, memory_device_build_list, opaque);
50     return 0;
51 }
52 
53 static int memory_device_used_region_size(Object *obj, void *opaque)
54 {
55     uint64_t *size = opaque;
56 
57     if (object_dynamic_cast(obj, TYPE_MEMORY_DEVICE)) {
58         const DeviceState *dev = DEVICE(obj);
59         const MemoryDeviceState *md = MEMORY_DEVICE(obj);
60         const MemoryDeviceClass *mdc = MEMORY_DEVICE_GET_CLASS(obj);
61 
62         if (dev->realized) {
63             *size += mdc->get_region_size(md);
64         }
65     }
66 
67     object_child_foreach(obj, memory_device_used_region_size, opaque);
68     return 0;
69 }
70 
71 static void memory_device_check_addable(MachineState *ms, uint64_t size,
72                                         Error **errp)
73 {
74     uint64_t used_region_size = 0;
75 
76     /* we will need a new memory slot for kvm and vhost */
77     if (kvm_enabled() && !kvm_has_free_slot(ms)) {
78         error_setg(errp, "hypervisor has no free memory slots left");
79         return;
80     }
81     if (!vhost_has_free_slot()) {
82         error_setg(errp, "a used vhost backend has no free memory slots left");
83         return;
84     }
85 
86     /* will we exceed the total amount of memory specified */
87     memory_device_used_region_size(OBJECT(ms), &used_region_size);
88     if (used_region_size + size > ms->maxram_size - ms->ram_size) {
89         error_setg(errp, "not enough space, currently 0x%" PRIx64
90                    " in use of total hot pluggable 0x" RAM_ADDR_FMT,
91                    used_region_size, ms->maxram_size - ms->ram_size);
92         return;
93     }
94 
95 }
96 
97 uint64_t memory_device_get_free_addr(MachineState *ms, const uint64_t *hint,
98                                      uint64_t align, uint64_t size,
99                                      Error **errp)
100 {
101     uint64_t address_space_start, address_space_end;
102     GSList *list = NULL, *item;
103     uint64_t new_addr = 0;
104 
105     if (!ms->device_memory) {
106         error_setg(errp, "memory devices (e.g. for memory hotplug) are not "
107                          "supported by the machine");
108         return 0;
109     }
110 
111     if (!memory_region_size(&ms->device_memory->mr)) {
112         error_setg(errp, "memory devices (e.g. for memory hotplug) are not "
113                          "enabled, please specify the maxmem option");
114         return 0;
115     }
116     address_space_start = ms->device_memory->base;
117     address_space_end = address_space_start +
118                         memory_region_size(&ms->device_memory->mr);
119     g_assert(QEMU_ALIGN_UP(address_space_start, align) == address_space_start);
120     g_assert(address_space_end >= address_space_start);
121 
122     memory_device_check_addable(ms, size, errp);
123     if (*errp) {
124         return 0;
125     }
126 
127     if (hint && QEMU_ALIGN_UP(*hint, align) != *hint) {
128         error_setg(errp, "address must be aligned to 0x%" PRIx64 " bytes",
129                    align);
130         return 0;
131     }
132 
133     if (QEMU_ALIGN_UP(size, align) != size) {
134         error_setg(errp, "backend memory size must be multiple of 0x%"
135                    PRIx64, align);
136         return 0;
137     }
138 
139     if (hint) {
140         new_addr = *hint;
141         if (new_addr < address_space_start) {
142             error_setg(errp, "can't add memory [0x%" PRIx64 ":0x%" PRIx64
143                        "] at 0x%" PRIx64, new_addr, size, address_space_start);
144             return 0;
145         } else if ((new_addr + size) > address_space_end) {
146             error_setg(errp, "can't add memory [0x%" PRIx64 ":0x%" PRIx64
147                        "] beyond 0x%" PRIx64, new_addr, size,
148                        address_space_end);
149             return 0;
150         }
151     } else {
152         new_addr = address_space_start;
153     }
154 
155     /* find address range that will fit new memory device */
156     object_child_foreach(OBJECT(ms), memory_device_build_list, &list);
157     for (item = list; item; item = g_slist_next(item)) {
158         const MemoryDeviceState *md = item->data;
159         const MemoryDeviceClass *mdc = MEMORY_DEVICE_GET_CLASS(OBJECT(md));
160         uint64_t md_size, md_addr;
161 
162         md_addr = mdc->get_addr(md);
163         md_size = mdc->get_region_size(md);
164         if (*errp) {
165             goto out;
166         }
167 
168         if (ranges_overlap(md_addr, md_size, new_addr, size)) {
169             if (hint) {
170                 const DeviceState *d = DEVICE(md);
171                 error_setg(errp, "address range conflicts with '%s'", d->id);
172                 goto out;
173             }
174             new_addr = QEMU_ALIGN_UP(md_addr + md_size, align);
175         }
176     }
177 
178     if (new_addr + size > address_space_end) {
179         error_setg(errp, "could not find position in guest address space for "
180                    "memory device - memory fragmented due to alignments");
181         goto out;
182     }
183 out:
184     g_slist_free(list);
185     return new_addr;
186 }
187 
188 MemoryDeviceInfoList *qmp_memory_device_list(void)
189 {
190     GSList *devices = NULL, *item;
191     MemoryDeviceInfoList *list = NULL, *prev = NULL;
192 
193     object_child_foreach(qdev_get_machine(), memory_device_build_list,
194                          &devices);
195 
196     for (item = devices; item; item = g_slist_next(item)) {
197         const MemoryDeviceState *md = MEMORY_DEVICE(item->data);
198         const MemoryDeviceClass *mdc = MEMORY_DEVICE_GET_CLASS(item->data);
199         MemoryDeviceInfoList *elem = g_new0(MemoryDeviceInfoList, 1);
200         MemoryDeviceInfo *info = g_new0(MemoryDeviceInfo, 1);
201 
202         mdc->fill_device_info(md, info);
203 
204         elem->value = info;
205         elem->next = NULL;
206         if (prev) {
207             prev->next = elem;
208         } else {
209             list = elem;
210         }
211         prev = elem;
212     }
213 
214     g_slist_free(devices);
215 
216     return list;
217 }
218 
219 static int memory_device_plugged_size(Object *obj, void *opaque)
220 {
221     uint64_t *size = opaque;
222 
223     if (object_dynamic_cast(obj, TYPE_MEMORY_DEVICE)) {
224         const DeviceState *dev = DEVICE(obj);
225         const MemoryDeviceState *md = MEMORY_DEVICE(obj);
226         const MemoryDeviceClass *mdc = MEMORY_DEVICE_GET_CLASS(obj);
227 
228         if (dev->realized) {
229             *size += mdc->get_plugged_size(md);
230         }
231     }
232 
233     object_child_foreach(obj, memory_device_plugged_size, opaque);
234     return 0;
235 }
236 
237 uint64_t get_plugged_memory_size(void)
238 {
239     uint64_t size = 0;
240 
241     memory_device_plugged_size(qdev_get_machine(), &size);
242 
243     return size;
244 }
245 
246 void memory_device_plug_region(MachineState *ms, MemoryRegion *mr,
247                                uint64_t addr)
248 {
249     /* we expect a previous call to memory_device_get_free_addr() */
250     g_assert(ms->device_memory);
251 
252     memory_region_add_subregion(&ms->device_memory->mr,
253                                 addr - ms->device_memory->base, mr);
254 }
255 
256 void memory_device_unplug_region(MachineState *ms, MemoryRegion *mr)
257 {
258     /* we expect a previous call to memory_device_get_free_addr() */
259     g_assert(ms->device_memory);
260 
261     memory_region_del_subregion(&ms->device_memory->mr, mr);
262 }
263 
264 static const TypeInfo memory_device_info = {
265     .name          = TYPE_MEMORY_DEVICE,
266     .parent        = TYPE_INTERFACE,
267     .class_size = sizeof(MemoryDeviceClass),
268 };
269 
270 static void memory_device_register_types(void)
271 {
272     type_register_static(&memory_device_info);
273 }
274 
275 type_init(memory_device_register_types)
276