xref: /openbmc/qemu/hw/mem/memory-device.c (revision 09a274d8)
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 #include "trace.h"
21 
22 static gint memory_device_addr_sort(gconstpointer a, gconstpointer b)
23 {
24     const MemoryDeviceState *md_a = MEMORY_DEVICE(a);
25     const MemoryDeviceState *md_b = MEMORY_DEVICE(b);
26     const MemoryDeviceClass *mdc_a = MEMORY_DEVICE_GET_CLASS(a);
27     const MemoryDeviceClass *mdc_b = MEMORY_DEVICE_GET_CLASS(b);
28     const uint64_t addr_a = mdc_a->get_addr(md_a);
29     const uint64_t addr_b = mdc_b->get_addr(md_b);
30 
31     if (addr_a > addr_b) {
32         return 1;
33     } else if (addr_a < addr_b) {
34         return -1;
35     }
36     return 0;
37 }
38 
39 static int memory_device_build_list(Object *obj, void *opaque)
40 {
41     GSList **list = opaque;
42 
43     if (object_dynamic_cast(obj, TYPE_MEMORY_DEVICE)) {
44         DeviceState *dev = DEVICE(obj);
45         if (dev->realized) { /* only realized memory devices matter */
46             *list = g_slist_insert_sorted(*list, dev, memory_device_addr_sort);
47         }
48     }
49 
50     object_child_foreach(obj, memory_device_build_list, opaque);
51     return 0;
52 }
53 
54 static int memory_device_used_region_size(Object *obj, void *opaque)
55 {
56     uint64_t *size = opaque;
57 
58     if (object_dynamic_cast(obj, TYPE_MEMORY_DEVICE)) {
59         const DeviceState *dev = DEVICE(obj);
60         const MemoryDeviceState *md = MEMORY_DEVICE(obj);
61 
62         if (dev->realized) {
63             *size += memory_device_get_region_size(md, &error_abort);
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 < used_region_size ||
89         used_region_size + size > ms->maxram_size - ms->ram_size) {
90         error_setg(errp, "not enough space, currently 0x%" PRIx64
91                    " in use of total space for memory devices 0x" RAM_ADDR_FMT,
92                    used_region_size, ms->maxram_size - ms->ram_size);
93         return;
94     }
95 
96 }
97 
98 static uint64_t memory_device_get_free_addr(MachineState *ms,
99                                             const uint64_t *hint,
100                                             uint64_t align, uint64_t size,
101                                             Error **errp)
102 {
103     GSList *list = NULL, *item;
104     Range as, new = range_empty;
105 
106     if (!ms->device_memory) {
107         error_setg(errp, "memory devices (e.g. for memory hotplug) are not "
108                          "supported by the machine");
109         return 0;
110     }
111 
112     if (!memory_region_size(&ms->device_memory->mr)) {
113         error_setg(errp, "memory devices (e.g. for memory hotplug) are not "
114                          "enabled, please specify the maxmem option");
115         return 0;
116     }
117     range_init_nofail(&as, ms->device_memory->base,
118                       memory_region_size(&ms->device_memory->mr));
119 
120     /* start of address space indicates the maximum alignment we expect */
121     if (!QEMU_IS_ALIGNED(range_lob(&as), align)) {
122         error_setg(errp, "the alignment (0x%" PRIx64 ") is not supported",
123                    align);
124         return 0;
125     }
126 
127     memory_device_check_addable(ms, size, errp);
128     if (*errp) {
129         return 0;
130     }
131 
132     if (hint && !QEMU_IS_ALIGNED(*hint, align)) {
133         error_setg(errp, "address must be aligned to 0x%" PRIx64 " bytes",
134                    align);
135         return 0;
136     }
137 
138     if (!QEMU_IS_ALIGNED(size, align)) {
139         error_setg(errp, "backend memory size must be multiple of 0x%"
140                    PRIx64, align);
141         return 0;
142     }
143 
144     if (hint) {
145         if (range_init(&new, *hint, size) || !range_contains_range(&as, &new)) {
146             error_setg(errp, "can't add memory device [0x%" PRIx64 ":0x%" PRIx64
147                        "], usable range for memory devices [0x%" PRIx64 ":0x%"
148                        PRIx64 "]", *hint, size, range_lob(&as),
149                        range_size(&as));
150             return 0;
151         }
152     } else {
153         if (range_init(&new, range_lob(&as), size)) {
154             error_setg(errp, "can't add memory device, device too big");
155             return 0;
156         }
157     }
158 
159     /* find address range that will fit new memory device */
160     object_child_foreach(OBJECT(ms), memory_device_build_list, &list);
161     for (item = list; item; item = g_slist_next(item)) {
162         const MemoryDeviceState *md = item->data;
163         const MemoryDeviceClass *mdc = MEMORY_DEVICE_GET_CLASS(OBJECT(md));
164         uint64_t next_addr;
165         Range tmp;
166 
167         range_init_nofail(&tmp, mdc->get_addr(md),
168                           memory_device_get_region_size(md, &error_abort));
169 
170         if (range_overlaps_range(&tmp, &new)) {
171             if (hint) {
172                 const DeviceState *d = DEVICE(md);
173                 error_setg(errp, "address range conflicts with memory device"
174                            " id='%s'", d->id ? d->id : "(unnamed)");
175                 goto out;
176             }
177 
178             next_addr = QEMU_ALIGN_UP(range_upb(&tmp) + 1, align);
179             if (!next_addr || range_init(&new, next_addr, range_size(&new))) {
180                 range_make_empty(&new);
181                 break;
182             }
183         }
184     }
185 
186     if (!range_contains_range(&as, &new)) {
187         error_setg(errp, "could not find position in guest address space for "
188                    "memory device - memory fragmented due to alignments");
189         goto out;
190     }
191 out:
192     g_slist_free(list);
193     return range_lob(&new);
194 }
195 
196 MemoryDeviceInfoList *qmp_memory_device_list(void)
197 {
198     GSList *devices = NULL, *item;
199     MemoryDeviceInfoList *list = NULL, *prev = NULL;
200 
201     object_child_foreach(qdev_get_machine(), memory_device_build_list,
202                          &devices);
203 
204     for (item = devices; item; item = g_slist_next(item)) {
205         const MemoryDeviceState *md = MEMORY_DEVICE(item->data);
206         const MemoryDeviceClass *mdc = MEMORY_DEVICE_GET_CLASS(item->data);
207         MemoryDeviceInfoList *elem = g_new0(MemoryDeviceInfoList, 1);
208         MemoryDeviceInfo *info = g_new0(MemoryDeviceInfo, 1);
209 
210         mdc->fill_device_info(md, info);
211 
212         elem->value = info;
213         elem->next = NULL;
214         if (prev) {
215             prev->next = elem;
216         } else {
217             list = elem;
218         }
219         prev = elem;
220     }
221 
222     g_slist_free(devices);
223 
224     return list;
225 }
226 
227 static int memory_device_plugged_size(Object *obj, void *opaque)
228 {
229     uint64_t *size = opaque;
230 
231     if (object_dynamic_cast(obj, TYPE_MEMORY_DEVICE)) {
232         const DeviceState *dev = DEVICE(obj);
233         const MemoryDeviceState *md = MEMORY_DEVICE(obj);
234         const MemoryDeviceClass *mdc = MEMORY_DEVICE_GET_CLASS(obj);
235 
236         if (dev->realized) {
237             *size += mdc->get_plugged_size(md, &error_abort);
238         }
239     }
240 
241     object_child_foreach(obj, memory_device_plugged_size, opaque);
242     return 0;
243 }
244 
245 uint64_t get_plugged_memory_size(void)
246 {
247     uint64_t size = 0;
248 
249     memory_device_plugged_size(qdev_get_machine(), &size);
250 
251     return size;
252 }
253 
254 void memory_device_pre_plug(MemoryDeviceState *md, MachineState *ms,
255                             const uint64_t *legacy_align, Error **errp)
256 {
257     const MemoryDeviceClass *mdc = MEMORY_DEVICE_GET_CLASS(md);
258     Error *local_err = NULL;
259     uint64_t addr, align;
260     MemoryRegion *mr;
261 
262     mr = mdc->get_memory_region(md, &local_err);
263     if (local_err) {
264         goto out;
265     }
266 
267     align = legacy_align ? *legacy_align : memory_region_get_alignment(mr);
268     addr = mdc->get_addr(md);
269     addr = memory_device_get_free_addr(ms, !addr ? NULL : &addr, align,
270                                        memory_region_size(mr), &local_err);
271     if (local_err) {
272         goto out;
273     }
274     mdc->set_addr(md, addr, &local_err);
275     if (!local_err) {
276         trace_memory_device_pre_plug(DEVICE(md)->id ? DEVICE(md)->id : "",
277                                      addr);
278     }
279 out:
280     error_propagate(errp, local_err);
281 }
282 
283 void memory_device_plug(MemoryDeviceState *md, MachineState *ms)
284 {
285     const MemoryDeviceClass *mdc = MEMORY_DEVICE_GET_CLASS(md);
286     const uint64_t addr = mdc->get_addr(md);
287     MemoryRegion *mr;
288 
289     /*
290      * We expect that a previous call to memory_device_pre_plug() succeeded, so
291      * it can't fail at this point.
292      */
293     mr = mdc->get_memory_region(md, &error_abort);
294     g_assert(ms->device_memory);
295 
296     memory_region_add_subregion(&ms->device_memory->mr,
297                                 addr - ms->device_memory->base, mr);
298     trace_memory_device_plug(DEVICE(md)->id ? DEVICE(md)->id : "", addr);
299 }
300 
301 void memory_device_unplug(MemoryDeviceState *md, MachineState *ms)
302 {
303     const MemoryDeviceClass *mdc = MEMORY_DEVICE_GET_CLASS(md);
304     MemoryRegion *mr;
305 
306     /*
307      * We expect that a previous call to memory_device_pre_plug() succeeded, so
308      * it can't fail at this point.
309      */
310     mr = mdc->get_memory_region(md, &error_abort);
311     g_assert(ms->device_memory);
312 
313     memory_region_del_subregion(&ms->device_memory->mr, mr);
314     trace_memory_device_unplug(DEVICE(md)->id ? DEVICE(md)->id : "",
315                                mdc->get_addr(md));
316 }
317 
318 uint64_t memory_device_get_region_size(const MemoryDeviceState *md,
319                                        Error **errp)
320 {
321     const MemoryDeviceClass *mdc = MEMORY_DEVICE_GET_CLASS(md);
322     MemoryRegion *mr;
323 
324     /* dropping const here is fine as we don't touch the memory region */
325     mr = mdc->get_memory_region((MemoryDeviceState *)md, errp);
326     if (!mr) {
327         return 0;
328     }
329 
330     return memory_region_size(mr);
331 }
332 
333 static const TypeInfo memory_device_info = {
334     .name          = TYPE_MEMORY_DEVICE,
335     .parent        = TYPE_INTERFACE,
336     .class_size = sizeof(MemoryDeviceClass),
337 };
338 
339 static void memory_device_register_types(void)
340 {
341     type_register_static(&memory_device_info);
342 }
343 
344 type_init(memory_device_register_types)
345