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 "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     uint64_t address_space_start, address_space_end;
 104     GSList *list = NULL, *item;
 105     uint64_t new_addr = 0;
 106
 107     if (!ms->device_memory) {
 108         error_setg(errp, "memory devices (e.g. for memory hotplug) are not "
 109                          "supported by the machine");
 110         return 0;
 111     }
 112
 113     if (!memory_region_size(&ms->device_memory->mr)) {
 114         error_setg(errp, "memory devices (e.g. for memory hotplug) are not "
 115                          "enabled, please specify the maxmem option");
 116         return 0;
 117     }
 118     address_space_start = ms->device_memory->base;
 119     address_space_end = address_space_start +
 120                         memory_region_size(&ms->device_memory->mr);
 121     g_assert(address_space_end >= address_space_start);
 122
 123     /* address_space_start indicates the maximum alignment we expect */
 124     if (!QEMU_IS_ALIGNED(address_space_start, align)) {
 125         error_setg(errp, "the alignment (0x%" PRIx64 ") is not supported",
 126                    align);
 127         return 0;
 128     }
 129
 130     memory_device_check_addable(ms, size, errp);
 131     if (*errp) {
 132         return 0;
 133     }
 134
 135     if (hint && !QEMU_IS_ALIGNED(*hint, align)) {
 136         error_setg(errp, "address must be aligned to 0x%" PRIx64 " bytes",
 137                    align);
 138         return 0;
 139     }
 140
 141     if (!QEMU_IS_ALIGNED(size, align)) {
 142         error_setg(errp, "backend memory size must be multiple of 0x%"
 143                    PRIx64, align);
 144         return 0;
 145     }
 146
 147     if (hint) {
 148         new_addr = *hint;
 149         if (new_addr < address_space_start) {
 150             error_setg(errp, "can't add memory device [0x%" PRIx64 ":0x%" PRIx64
 151                        "] before 0x%" PRIx64, new_addr, size,
 152                        address_space_start);
 153             return 0;
 154         } else if ((new_addr + size) > address_space_end) {
 155             error_setg(errp, "can't add memory device [0x%" PRIx64 ":0x%" PRIx64
 156                        "] beyond 0x%" PRIx64, new_addr, size,
 157                        address_space_end);
 158             return 0;
 159         }
 160     } else {
 161         new_addr = address_space_start;
 162     }
 163
 164     /* find address range that will fit new memory device */
 165     object_child_foreach(OBJECT(ms), memory_device_build_list, &list);
 166     for (item = list; item; item = g_slist_next(item)) {
 167         const MemoryDeviceState *md = item->data;
 168         const MemoryDeviceClass *mdc = MEMORY_DEVICE_GET_CLASS(OBJECT(md));
 169         uint64_t md_size, md_addr;
 170
 171         md_addr = mdc->get_addr(md);
 172         md_size = memory_device_get_region_size(md, &error_abort);
 173
 174         if (ranges_overlap(md_addr, md_size, new_addr, size)) {
 175             if (hint) {
 176                 const DeviceState *d = DEVICE(md);
 177                 error_setg(errp, "address range conflicts with memory device"
 178                            " id='%s'", d->id ? d->id : "(unnamed)");
 179                 goto out;
 180             }
 181             new_addr = QEMU_ALIGN_UP(md_addr + md_size, align);
 182         }
 183     }
 184
 185     if (new_addr + size > address_space_end) {
 186         error_setg(errp, "could not find position in guest address space for "
 187                    "memory device - memory fragmented due to alignments");
 188         goto out;
 189     }
 190 out:
 191     g_slist_free(list);
 192     return new_addr;
 193 }
 194
 195 MemoryDeviceInfoList *qmp_memory_device_list(void)
 196 {
 197     GSList *devices = NULL, *item;
 198     MemoryDeviceInfoList *list = NULL, *prev = NULL;
 199
 200     object_child_foreach(qdev_get_machine(), memory_device_build_list,
 201                          &devices);
 202
 203     for (item = devices; item; item = g_slist_next(item)) {
 204         const MemoryDeviceState *md = MEMORY_DEVICE(item->data);
 205         const MemoryDeviceClass *mdc = MEMORY_DEVICE_GET_CLASS(item->data);
 206         MemoryDeviceInfoList *elem = g_new0(MemoryDeviceInfoList, 1);
 207         MemoryDeviceInfo *info = g_new0(MemoryDeviceInfo, 1);
 208
 209         mdc->fill_device_info(md, info);
 210
 211         elem->value = info;
 212         elem->next = NULL;
 213         if (prev) {
 214             prev->next = elem;
 215         } else {
 216             list = elem;
 217         }
 218         prev = elem;
 219     }
 220
 221     g_slist_free(devices);
 222
 223     return list;
 224 }
 225
 226 static int memory_device_plugged_size(Object *obj, void *opaque)
 227 {
 228     uint64_t *size = opaque;
 229
 230     if (object_dynamic_cast(obj, TYPE_MEMORY_DEVICE)) {
 231         const DeviceState *dev = DEVICE(obj);
 232         const MemoryDeviceState *md = MEMORY_DEVICE(obj);
 233         const MemoryDeviceClass *mdc = MEMORY_DEVICE_GET_CLASS(obj);
 234
 235         if (dev->realized) {
 236             *size += mdc->get_plugged_size(md, &error_abort);
 237         }
 238     }
 239
 240     object_child_foreach(obj, memory_device_plugged_size, opaque);
 241     return 0;
 242 }
 243
 244 uint64_t get_plugged_memory_size(void)
 245 {
 246     uint64_t size = 0;
 247
 248     memory_device_plugged_size(qdev_get_machine(), &size);
 249
 250     return size;
 251 }
 252
 253 void memory_device_pre_plug(MemoryDeviceState *md, MachineState *ms,
 254                             const uint64_t *legacy_align, Error **errp)
 255 {
 256     const MemoryDeviceClass *mdc = MEMORY_DEVICE_GET_CLASS(md);
 257     Error *local_err = NULL;
 258     uint64_t addr, align;
 259     MemoryRegion *mr;
 260
 261     mr = mdc->get_memory_region(md, &local_err);
 262     if (local_err) {
 263         goto out;
 264     }
 265
 266     align = legacy_align ? *legacy_align : memory_region_get_alignment(mr);
 267     addr = mdc->get_addr(md);
 268     addr = memory_device_get_free_addr(ms, !addr ? NULL : &addr, align,
 269                                        memory_region_size(mr), &local_err);
 270     if (local_err) {
 271         goto out;
 272     }
 273     mdc->set_addr(md, addr, &local_err);
 274     if (!local_err) {
 275         trace_memory_device_pre_plug(DEVICE(md)->id ? DEVICE(md)->id : "",
 276                                      addr);
 277     }
 278 out:
 279     error_propagate(errp, local_err);
 280 }
 281
 282 void memory_device_plug(MemoryDeviceState *md, MachineState *ms)
 283 {
 284     const MemoryDeviceClass *mdc = MEMORY_DEVICE_GET_CLASS(md);
 285     const uint64_t addr = mdc->get_addr(md);
 286     MemoryRegion *mr;
 287
 288     /*
 289      * We expect that a previous call to memory_device_pre_plug() succeeded, so
 290      * it can't fail at this point.
 291      */
 292     mr = mdc->get_memory_region(md, &error_abort);
 293     g_assert(ms->device_memory);
 294
 295     memory_region_add_subregion(&ms->device_memory->mr,
 296                                 addr - ms->device_memory->base, mr);
 297     trace_memory_device_plug(DEVICE(md)->id ? DEVICE(md)->id : "", addr);
 298 }
 299
 300 void memory_device_unplug(MemoryDeviceState *md, MachineState *ms)
 301 {
 302     const MemoryDeviceClass *mdc = MEMORY_DEVICE_GET_CLASS(md);
 303     MemoryRegion *mr;
 304
 305     /*
 306      * We expect that a previous call to memory_device_pre_plug() succeeded, so
 307      * it can't fail at this point.
 308      */
 309     mr = mdc->get_memory_region(md, &error_abort);
 310     g_assert(ms->device_memory);
 311
 312     memory_region_del_subregion(&ms->device_memory->mr, mr);
 313     trace_memory_device_unplug(DEVICE(md)->id ? DEVICE(md)->id : "",
 314                                mdc->get_addr(md));
 315 }
 316
 317 uint64_t memory_device_get_region_size(const MemoryDeviceState *md,
 318                                        Error **errp)
 319 {
 320     const MemoryDeviceClass *mdc = MEMORY_DEVICE_GET_CLASS(md);
 321     MemoryRegion *mr;
 322
 323     /* dropping const here is fine as we don't touch the memory region */
 324     mr = mdc->get_memory_region((MemoryDeviceState *)md, errp);
 325     if (!mr) {
 326         return 0;
 327     }
 328
 329     return memory_region_size(mr);
 330 }
 331
 332 static const TypeInfo memory_device_info = {
 333     .name          = TYPE_MEMORY_DEVICE,
 334     .parent        = TYPE_INTERFACE,
 335     .class_size = sizeof(MemoryDeviceClass),
 336 };
 337
 338 static void memory_device_register_types(void)
 339 {
 340     type_register_static(&memory_device_info);
 341 }
 342
 343 type_init(memory_device_register_types)