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