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     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)