hw/mem/memory-device.c

   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         error_setg(errp, "the alignment (0x%" PRIx64 ") is not supported",
 123                    align);
 124         return 0;
 125     }
 126
 127     memory_device_check_addable(ms, size, &err);
 128     if (err) {
 129         error_propagate(errp, err);
 130         return 0;
 131     }
 132
 133     if (hint && !QEMU_IS_ALIGNED(*hint, align)) {
 134         error_setg(errp, "address must be aligned to 0x%" PRIx64 " bytes",
 135                    align);
 136         return 0;
 137     }
 138
 139     if (!QEMU_IS_ALIGNED(size, align)) {
 140         error_setg(errp, "backend memory size must be multiple of 0x%"
 141                    PRIx64, align);
 142         return 0;
 143     }
 144
 145     if (hint) {
 146         if (range_init(&new, *hint, size) || !range_contains_range(&as, &new)) {
 147             error_setg(errp, "can't add memory device [0x%" PRIx64 ":0x%" PRIx64
 148                        "], usable range for memory devices [0x%" PRIx64 ":0x%"
 149                        PRIx64 "]", *hint, size, range_lob(&as),
 150                        range_size(&as));
 151             return 0;
 152         }
 153     } else {
 154         if (range_init(&new, range_lob(&as), size)) {
 155             error_setg(errp, "can't add memory device, device too big");
 156             return 0;
 157         }
 158     }
 159
 160     /* find address range that will fit new memory device */
 161     object_child_foreach(OBJECT(ms), memory_device_build_list, &list);
 162     for (item = list; item; item = g_slist_next(item)) {
 163         const MemoryDeviceState *md = item->data;
 164         const MemoryDeviceClass *mdc = MEMORY_DEVICE_GET_CLASS(OBJECT(md));
 165         uint64_t next_addr;
 166         Range tmp;
 167
 168         range_init_nofail(&tmp, mdc->get_addr(md),
 169                           memory_device_get_region_size(md, &error_abort));
 170
 171         if (range_overlaps_range(&tmp, &new)) {
 172             if (hint) {
 173                 const DeviceState *d = DEVICE(md);
 174                 error_setg(errp, "address range conflicts with memory device"
 175                            " id='%s'", d->id ? d->id : "(unnamed)");
 176                 goto out;
 177             }
 178
 179             next_addr = QEMU_ALIGN_UP(range_upb(&tmp) + 1, align);
 180             if (!next_addr || range_init(&new, next_addr, range_size(&new))) {
 181                 range_make_empty(&new);
 182                 break;
 183             }
 184         } else if (range_lob(&tmp) > range_upb(&new)) {
 185             break;
 186         }
 187     }
 188
 189     if (!range_contains_range(&as, &new)) {
 190         error_setg(errp, "could not find position in guest address space for "
 191                    "memory device - memory fragmented due to alignments");
 192     }
 193 out:
 194     g_slist_free(list);
 195     return range_lob(&new);
 196 }
 197
 198 MemoryDeviceInfoList *qmp_memory_device_list(void)
 199 {
 200     GSList *devices = NULL, *item;
 201     MemoryDeviceInfoList *list = NULL, *prev = NULL;
 202
 203     object_child_foreach(qdev_get_machine(), memory_device_build_list,
 204                          &devices);
 205
 206     for (item = devices; item; item = g_slist_next(item)) {
 207         const MemoryDeviceState *md = MEMORY_DEVICE(item->data);
 208         const MemoryDeviceClass *mdc = MEMORY_DEVICE_GET_CLASS(item->data);
 209         MemoryDeviceInfoList *elem = g_new0(MemoryDeviceInfoList, 1);
 210         MemoryDeviceInfo *info = g_new0(MemoryDeviceInfo, 1);
 211
 212         mdc->fill_device_info(md, info);
 213
 214         elem->value = info;
 215         elem->next = NULL;
 216         if (prev) {
 217             prev->next = elem;
 218         } else {
 219             list = elem;
 220         }
 221         prev = elem;
 222     }
 223
 224     g_slist_free(devices);
 225
 226     return list;
 227 }
 228
 229 static int memory_device_plugged_size(Object *obj, void *opaque)
 230 {
 231     uint64_t *size = opaque;
 232
 233     if (object_dynamic_cast(obj, TYPE_MEMORY_DEVICE)) {
 234         const DeviceState *dev = DEVICE(obj);
 235         const MemoryDeviceState *md = MEMORY_DEVICE(obj);
 236         const MemoryDeviceClass *mdc = MEMORY_DEVICE_GET_CLASS(obj);
 237
 238         if (dev->realized) {
 239             *size += mdc->get_plugged_size(md, &error_abort);
 240         }
 241     }
 242
 243     object_child_foreach(obj, memory_device_plugged_size, opaque);
 244     return 0;
 245 }
 246
 247 uint64_t get_plugged_memory_size(void)
 248 {
 249     uint64_t size = 0;
 250
 251     memory_device_plugged_size(qdev_get_machine(), &size);
 252
 253     return size;
 254 }
 255
 256 void memory_device_pre_plug(MemoryDeviceState *md, MachineState *ms,
 257                             const uint64_t *legacy_align, Error **errp)
 258 {
 259     const MemoryDeviceClass *mdc = MEMORY_DEVICE_GET_CLASS(md);
 260     Error *local_err = NULL;
 261     uint64_t addr, align;
 262     MemoryRegion *mr;
 263
 264     mr = mdc->get_memory_region(md, &local_err);
 265     if (local_err) {
 266         goto out;
 267     }
 268
 269     align = legacy_align ? *legacy_align : memory_region_get_alignment(mr);
 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)