qemu

FORK: QEMU emulator
git clone https://git.neptards.moe/neptards/qemu.git
Log | Files | Refs | Submodules | LICENSE

memory-device.c (10929B)


      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)