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 "qapi/error.h" 15 #include "hw/boards.h" 16 #include "qemu/range.h" 17 #include "hw/virtio/vhost.h" 18 #include "sysemu/kvm.h" 19 #include "trace.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 61 if (dev->realized) { 62 *size += memory_device_get_region_size(md, &error_abort); 63 } 64 } 65 66 object_child_foreach(obj, memory_device_used_region_size, opaque); 67 return 0; 68 } 69 70 static void memory_device_check_addable(MachineState *ms, uint64_t size, 71 Error **errp) 72 { 73 uint64_t used_region_size = 0; 74 75 /* we will need a new memory slot for kvm and vhost */ 76 if (kvm_enabled() && !kvm_has_free_slot(ms)) { 77 error_setg(errp, "hypervisor has no free memory slots left"); 78 return; 79 } 80 if (!vhost_has_free_slot()) { 81 error_setg(errp, "a used vhost backend has no free memory slots left"); 82 return; 83 } 84 85 /* will we exceed the total amount of memory specified */ 86 memory_device_used_region_size(OBJECT(ms), &used_region_size); 87 if (used_region_size + size < used_region_size || 88 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 space for memory devices 0x" RAM_ADDR_FMT, 91 used_region_size, ms->maxram_size - ms->ram_size); 92 return; 93 } 94 95 } 96 97 static uint64_t memory_device_get_free_addr(MachineState *ms, 98 const uint64_t *hint, 99 uint64_t align, uint64_t size, 100 Error **errp) 101 { 102 Error *err = NULL; 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 warn_report("the alignment (0x%" PRIx64 ") exceeds the expected" 123 " maximum alignment, memory will get fragmented and not" 124 " all 'maxmem' might be usable for memory devices.", 125 align); 126 } 127 128 memory_device_check_addable(ms, size, &err); 129 if (err) { 130 error_propagate(errp, err); 131 return 0; 132 } 133 134 if (hint && !QEMU_IS_ALIGNED(*hint, align)) { 135 error_setg(errp, "address must be aligned to 0x%" PRIx64 " bytes", 136 align); 137 return 0; 138 } 139 140 if (!QEMU_IS_ALIGNED(size, align)) { 141 error_setg(errp, "backend memory size must be multiple of 0x%" 142 PRIx64, align); 143 return 0; 144 } 145 146 if (hint) { 147 if (range_init(&new, *hint, size) || !range_contains_range(&as, &new)) { 148 error_setg(errp, "can't add memory device [0x%" PRIx64 ":0x%" PRIx64 149 "], usable range for memory devices [0x%" PRIx64 ":0x%" 150 PRIx64 "]", *hint, size, range_lob(&as), 151 range_size(&as)); 152 return 0; 153 } 154 } else { 155 if (range_init(&new, QEMU_ALIGN_UP(range_lob(&as), align), size)) { 156 error_setg(errp, "can't add memory device, device too big"); 157 return 0; 158 } 159 } 160 161 /* find address range that will fit new memory device */ 162 object_child_foreach(OBJECT(ms), memory_device_build_list, &list); 163 for (item = list; item; item = g_slist_next(item)) { 164 const MemoryDeviceState *md = item->data; 165 const MemoryDeviceClass *mdc = MEMORY_DEVICE_GET_CLASS(OBJECT(md)); 166 uint64_t next_addr; 167 Range tmp; 168 169 range_init_nofail(&tmp, mdc->get_addr(md), 170 memory_device_get_region_size(md, &error_abort)); 171 172 if (range_overlaps_range(&tmp, &new)) { 173 if (hint) { 174 const DeviceState *d = DEVICE(md); 175 error_setg(errp, "address range conflicts with memory device" 176 " id='%s'", d->id ? d->id : "(unnamed)"); 177 goto out; 178 } 179 180 next_addr = QEMU_ALIGN_UP(range_upb(&tmp) + 1, align); 181 if (!next_addr || range_init(&new, next_addr, range_size(&new))) { 182 range_make_empty(&new); 183 break; 184 } 185 } else if (range_lob(&tmp) > range_upb(&new)) { 186 break; 187 } 188 } 189 190 if (!range_contains_range(&as, &new)) { 191 error_setg(errp, "could not find position in guest address space for " 192 "memory device - memory fragmented due to alignments"); 193 } 194 out: 195 g_slist_free(list); 196 return range_lob(&new); 197 } 198 199 MemoryDeviceInfoList *qmp_memory_device_list(void) 200 { 201 GSList *devices = NULL, *item; 202 MemoryDeviceInfoList *list = NULL, **tail = &list; 203 204 object_child_foreach(qdev_get_machine(), memory_device_build_list, 205 &devices); 206 207 for (item = devices; item; item = g_slist_next(item)) { 208 const MemoryDeviceState *md = MEMORY_DEVICE(item->data); 209 const MemoryDeviceClass *mdc = MEMORY_DEVICE_GET_CLASS(item->data); 210 MemoryDeviceInfo *info = g_new0(MemoryDeviceInfo, 1); 211 212 mdc->fill_device_info(md, info); 213 214 QAPI_LIST_APPEND(tail, info); 215 } 216 217 g_slist_free(devices); 218 219 return list; 220 } 221 222 static int memory_device_plugged_size(Object *obj, void *opaque) 223 { 224 uint64_t *size = opaque; 225 226 if (object_dynamic_cast(obj, TYPE_MEMORY_DEVICE)) { 227 const DeviceState *dev = DEVICE(obj); 228 const MemoryDeviceState *md = MEMORY_DEVICE(obj); 229 const MemoryDeviceClass *mdc = MEMORY_DEVICE_GET_CLASS(obj); 230 231 if (dev->realized) { 232 *size += mdc->get_plugged_size(md, &error_abort); 233 } 234 } 235 236 object_child_foreach(obj, memory_device_plugged_size, opaque); 237 return 0; 238 } 239 240 uint64_t get_plugged_memory_size(void) 241 { 242 uint64_t size = 0; 243 244 memory_device_plugged_size(qdev_get_machine(), &size); 245 246 return size; 247 } 248 249 void memory_device_pre_plug(MemoryDeviceState *md, MachineState *ms, 250 const uint64_t *legacy_align, Error **errp) 251 { 252 const MemoryDeviceClass *mdc = MEMORY_DEVICE_GET_CLASS(md); 253 Error *local_err = NULL; 254 uint64_t addr, align = 0; 255 MemoryRegion *mr; 256 257 mr = mdc->get_memory_region(md, &local_err); 258 if (local_err) { 259 goto out; 260 } 261 262 if (legacy_align) { 263 align = *legacy_align; 264 } else { 265 if (mdc->get_min_alignment) { 266 align = mdc->get_min_alignment(md); 267 } 268 align = MAX(align, memory_region_get_alignment(mr)); 269 } 270 addr = mdc->get_addr(md); 271 addr = memory_device_get_free_addr(ms, !addr ? NULL : &addr, align, 272 memory_region_size(mr), &local_err); 273 if (local_err) { 274 goto out; 275 } 276 mdc->set_addr(md, addr, &local_err); 277 if (!local_err) { 278 trace_memory_device_pre_plug(DEVICE(md)->id ? DEVICE(md)->id : "", 279 addr); 280 } 281 out: 282 error_propagate(errp, local_err); 283 } 284 285 void memory_device_plug(MemoryDeviceState *md, MachineState *ms) 286 { 287 const MemoryDeviceClass *mdc = MEMORY_DEVICE_GET_CLASS(md); 288 const uint64_t addr = mdc->get_addr(md); 289 MemoryRegion *mr; 290 291 /* 292 * We expect that a previous call to memory_device_pre_plug() succeeded, so 293 * it can't fail at this point. 294 */ 295 mr = mdc->get_memory_region(md, &error_abort); 296 g_assert(ms->device_memory); 297 298 memory_region_add_subregion(&ms->device_memory->mr, 299 addr - ms->device_memory->base, mr); 300 trace_memory_device_plug(DEVICE(md)->id ? DEVICE(md)->id : "", addr); 301 } 302 303 void memory_device_unplug(MemoryDeviceState *md, MachineState *ms) 304 { 305 const MemoryDeviceClass *mdc = MEMORY_DEVICE_GET_CLASS(md); 306 MemoryRegion *mr; 307 308 /* 309 * We expect that a previous call to memory_device_pre_plug() succeeded, so 310 * it can't fail at this point. 311 */ 312 mr = mdc->get_memory_region(md, &error_abort); 313 g_assert(ms->device_memory); 314 315 memory_region_del_subregion(&ms->device_memory->mr, mr); 316 trace_memory_device_unplug(DEVICE(md)->id ? DEVICE(md)->id : "", 317 mdc->get_addr(md)); 318 } 319 320 uint64_t memory_device_get_region_size(const MemoryDeviceState *md, 321 Error **errp) 322 { 323 const MemoryDeviceClass *mdc = MEMORY_DEVICE_GET_CLASS(md); 324 MemoryRegion *mr; 325 326 /* dropping const here is fine as we don't touch the memory region */ 327 mr = mdc->get_memory_region((MemoryDeviceState *)md, errp); 328 if (!mr) { 329 return 0; 330 } 331 332 return memory_region_size(mr); 333 } 334 335 static const TypeInfo memory_device_info = { 336 .name = TYPE_MEMORY_DEVICE, 337 .parent = TYPE_INTERFACE, 338 .class_size = sizeof(MemoryDeviceClass), 339 }; 340 341 static void memory_device_register_types(void) 342 { 343 type_register_static(&memory_device_info); 344 } 345 346 type_init(memory_device_register_types) 347