sys/amd64/vmm/vmm_dev.c

   1 /*-
   2  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
   3  *
   4  * Copyright (c) 2011 NetApp, Inc.
   5  * All rights reserved.
   6  *
   7  * Redistribution and use in source and binary forms, with or without
   8  * modification, are permitted provided that the following conditions
   9  * are met:
  10  * 1. Redistributions of source code must retain the above copyright
  11  *    notice, this list of conditions and the following disclaimer.
  12  * 2. Redistributions in binary form must reproduce the above copyright
  13  *    notice, this list of conditions and the following disclaimer in the
  14  *    documentation and/or other materials provided with the distribution.
  15  *
  16  * THIS SOFTWARE IS PROVIDED BY NETAPP, INC ``AS IS'' AND
  17  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  18  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  19  * ARE DISCLAIMED.  IN NO EVENT SHALL NETAPP, INC OR CONTRIBUTORS BE LIABLE
  20  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  21  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  22  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  23  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  24  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  25  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  26  * SUCH DAMAGE.
  27  *
  28  * $FreeBSD$
  29  */
  30
  31 #include <sys/cdefs.h>
  32 __FBSDID("$FreeBSD$");
  33
  34 #include "opt_bhyve_snapshot.h"
  35
  36 #include <sys/param.h>
  37 #include <sys/kernel.h>
  38 #include <sys/jail.h>
  39 #include <sys/queue.h>
  40 #include <sys/lock.h>
  41 #include <sys/mutex.h>
  42 #include <sys/malloc.h>
  43 #include <sys/conf.h>
  44 #include <sys/sysctl.h>
  45 #include <sys/libkern.h>
  46 #include <sys/ioccom.h>
  47 #include <sys/mman.h>
  48 #include <sys/uio.h>
  49 #include <sys/proc.h>
  50
  51 #include <vm/vm.h>
  52 #include <vm/pmap.h>
  53 #include <vm/vm_map.h>
  54 #include <vm/vm_object.h>
  55
  56 #include <machine/vmparam.h>
  57 #include <machine/vmm.h>
  58 #include <machine/vmm_dev.h>
  59 #include <machine/vmm_instruction_emul.h>
  60 #include <machine/vmm_snapshot.h>
  61 #include <x86/apicreg.h>
  62
  63 #include "vmm_lapic.h"
  64 #include "vmm_stat.h"
  65 #include "vmm_mem.h"
  66 #include "io/ppt.h"
  67 #include "io/vatpic.h"
  68 #include "io/vioapic.h"
  69 #include "io/vhpet.h"
  70 #include "io/vrtc.h"
  71
  72 struct devmem_softc {
  73         int     segid;
  74         char    *name;
  75         struct cdev *cdev;
  76         struct vmmdev_softc *sc;
  77         SLIST_ENTRY(devmem_softc) link;
  78 };
  79
  80 struct vmmdev_softc {
  81         struct vm       *vm;            /* vm instance cookie */
  82         struct cdev     *cdev;
  83         SLIST_ENTRY(vmmdev_softc) link;
  84         SLIST_HEAD(, devmem_softc) devmem;
  85         int             flags;
  86 };
  87 #define VSC_LINKED              0x01
  88
  89 static SLIST_HEAD(, vmmdev_softc) head;
  90
  91 static unsigned pr_allow_flag;
  92 static struct mtx vmmdev_mtx;
  93
  94 static MALLOC_DEFINE(M_VMMDEV, "vmmdev", "vmmdev");
  95
  96 SYSCTL_DECL(_hw_vmm);
  97
  98 static int vmm_priv_check(struct ucred *ucred);
  99 static int devmem_create_cdev(const char *vmname, int id, char *devmem);
 100 static void devmem_destroy(void *arg);
 101
 102 static int
 103 vmm_priv_check(struct ucred *ucred)
 104 {
 105
 106         if (jailed(ucred) &&
 107             !(ucred->cr_prison->pr_allow & pr_allow_flag))
 108                 return (EPERM);
 109
 110         return (0);
 111 }
 112
 113 static int
 114 vcpu_lock_one(struct vmmdev_softc *sc, int vcpu)
 115 {
 116         int error;
 117
 118         if (vcpu < 0 || vcpu >= vm_get_maxcpus(sc->vm))
 119                 return (EINVAL);
 120
 121         error = vcpu_set_state(sc->vm, vcpu, VCPU_FROZEN, true);
 122         return (error);
 123 }
 124
 125 static void
 126 vcpu_unlock_one(struct vmmdev_softc *sc, int vcpu)
 127 {
 128         enum vcpu_state state;
 129
 130         state = vcpu_get_state(sc->vm, vcpu, NULL);
 131         if (state != VCPU_FROZEN) {
 132                 panic("vcpu %s(%d) has invalid state %d", vm_name(sc->vm),
 133                     vcpu, state);
 134         }
 135
 136         vcpu_set_state(sc->vm, vcpu, VCPU_IDLE, false);
 137 }
 138
 139 static int
 140 vcpu_lock_all(struct vmmdev_softc *sc)
 141 {
 142         int error, vcpu;
 143         uint16_t maxcpus;
 144
 145         maxcpus = vm_get_maxcpus(sc->vm);
 146         for (vcpu = 0; vcpu < maxcpus; vcpu++) {
 147                 error = vcpu_lock_one(sc, vcpu);
 148                 if (error)
 149                         break;
 150         }
 151
 152         if (error) {
 153                 while (--vcpu >= 0)
 154                         vcpu_unlock_one(sc, vcpu);
 155         }
 156
 157         return (error);
 158 }
 159
 160 static void
 161 vcpu_unlock_all(struct vmmdev_softc *sc)
 162 {
 163         int vcpu;
 164         uint16_t maxcpus;
 165
 166         maxcpus = vm_get_maxcpus(sc->vm);
 167         for (vcpu = 0; vcpu < maxcpus; vcpu++)
 168                 vcpu_unlock_one(sc, vcpu);
 169 }
 170
 171 static struct vmmdev_softc *
 172 vmmdev_lookup(const char *name)
 173 {
 174         struct vmmdev_softc *sc;
 175
 176 #ifdef notyet   /* XXX kernel is not compiled with invariants */
 177         mtx_assert(&vmmdev_mtx, MA_OWNED);
 178 #endif
 179
 180         SLIST_FOREACH(sc, &head, link) {
 181                 if (strcmp(name, vm_name(sc->vm)) == 0)
 182                         break;
 183         }
 184
 185         return (sc);
 186 }
 187
 188 static struct vmmdev_softc *
 189 vmmdev_lookup2(struct cdev *cdev)
 190 {
 191
 192         return (cdev->si_drv1);
 193 }
 194
 195 static int
 196 vmmdev_rw(struct cdev *cdev, struct uio *uio, int flags)
 197 {
 198         int error, off, c, prot;
 199         vm_paddr_t gpa, maxaddr;
 200         void *hpa, *cookie;
 201         struct vmmdev_softc *sc;
 202         uint16_t lastcpu;
 203
 204         error = vmm_priv_check(curthread->td_ucred);
 205         if (error)
 206                 return (error);
 207
 208         sc = vmmdev_lookup2(cdev);
 209         if (sc == NULL)
 210                 return (ENXIO);
 211
 212         /*
 213          * Get a read lock on the guest memory map by freezing any vcpu.
 214          */
 215         lastcpu = vm_get_maxcpus(sc->vm) - 1;
 216         error = vcpu_lock_one(sc, lastcpu);
 217         if (error)
 218                 return (error);
 219
 220         prot = (uio->uio_rw == UIO_WRITE ? VM_PROT_WRITE : VM_PROT_READ);
 221         maxaddr = vmm_sysmem_maxaddr(sc->vm);
 222         while (uio->uio_resid > 0 && error == 0) {
 223                 gpa = uio->uio_offset;
 224                 off = gpa & PAGE_MASK;
 225                 c = min(uio->uio_resid, PAGE_SIZE - off);
 226
 227                 /*
 228                  * The VM has a hole in its physical memory map. If we want to
 229                  * use 'dd' to inspect memory beyond the hole we need to
 230                  * provide bogus data for memory that lies in the hole.
 231                  *
 232                  * Since this device does not support lseek(2), dd(1) will
 233                  * read(2) blocks of data to simulate the lseek(2).
 234                  */
 235                 hpa = vm_gpa_hold(sc->vm, lastcpu, gpa, c,
 236                     prot, &cookie);
 237                 if (hpa == NULL) {
 238                         if (uio->uio_rw == UIO_READ && gpa < maxaddr)
 239                                 error = uiomove(__DECONST(void *, zero_region),
 240                                     c, uio);
 241                         else
 242                                 error = EFAULT;
 243                 } else {
 244                         error = uiomove(hpa, c, uio);
 245                         vm_gpa_release(cookie);
 246                 }
 247         }
 248         vcpu_unlock_one(sc, lastcpu);
 249         return (error);
 250 }
 251
 252 CTASSERT(sizeof(((struct vm_memseg *)0)->name) >= VM_MAX_SUFFIXLEN + 1);
 253
 254 static int
 255 get_memseg(struct vmmdev_softc *sc, struct vm_memseg *mseg, size_t len)
 256 {
 257         struct devmem_softc *dsc;
 258         int error;
 259         bool sysmem;
 260
 261         error = vm_get_memseg(sc->vm, mseg->segid, &mseg->len, &sysmem, NULL);
 262         if (error || mseg->len == 0)
 263                 return (error);
 264
 265         if (!sysmem) {
 266                 SLIST_FOREACH(dsc, &sc->devmem, link) {
 267                         if (dsc->segid == mseg->segid)
 268                                 break;
 269                 }
 270                 KASSERT(dsc != NULL, ("%s: devmem segment %d not found",
 271                     __func__, mseg->segid));
 272                 error = copystr(dsc->name, mseg->name, len, NULL);
 273         } else {
 274                 bzero(mseg->name, len);
 275         }
 276
 277         return (error);
 278 }
 279
 280 static int
 281 alloc_memseg(struct vmmdev_softc *sc, struct vm_memseg *mseg, size_t len)
 282 {
 283         char *name;
 284         int error;
 285         bool sysmem;
 286
 287         error = 0;
 288         name = NULL;
 289         sysmem = true;
 290
 291         /*
 292          * The allocation is lengthened by 1 to hold a terminating NUL.  It'll
 293          * by stripped off when devfs processes the full string.
 294          */
 295         if (VM_MEMSEG_NAME(mseg)) {
 296                 sysmem = false;
 297                 name = malloc(len, M_VMMDEV, M_WAITOK);
 298                 error = copystr(mseg->name, name, len, NULL);
 299                 if (error)
 300                         goto done;
 301         }
 302
 303         error = vm_alloc_memseg(sc->vm, mseg->segid, mseg->len, sysmem);
 304         if (error)
 305                 goto done;
 306
 307         if (VM_MEMSEG_NAME(mseg)) {
 308                 error = devmem_create_cdev(vm_name(sc->vm), mseg->segid, name);
 309                 if (error)
 310                         vm_free_memseg(sc->vm, mseg->segid);
 311                 else
 312                         name = NULL;    /* freed when 'cdev' is destroyed */
 313         }
 314 done:
 315         free(name, M_VMMDEV);
 316         return (error);
 317 }
 318
 319 static int
 320 vm_get_register_set(struct vm *vm, int vcpu, unsigned int count, int *regnum,
 321     uint64_t *regval)
 322 {
 323         int error, i;
 324
 325         error = 0;
 326         for (i = 0; i < count; i++) {
 327                 error = vm_get_register(vm, vcpu, regnum[i], &regval[i]);
 328                 if (error)
 329                         break;
 330         }
 331         return (error);
 332 }
 333
 334 static int
 335 vm_set_register_set(struct vm *vm, int vcpu, unsigned int count, int *regnum,
 336     uint64_t *regval)
 337 {
 338         int error, i;
 339
 340         error = 0;
 341         for (i = 0; i < count; i++) {
 342                 error = vm_set_register(vm, vcpu, regnum[i], regval[i]);
 343                 if (error)
 344                         break;
 345         }
 346         return (error);
 347 }
 348
 349 static int
 350 vmmdev_ioctl(struct cdev *cdev, u_long cmd, caddr_t data, int fflag,
 351              struct thread *td)
 352 {
 353         int error, vcpu, state_changed, size;
 354         cpuset_t *cpuset;
 355         struct vmmdev_softc *sc;
 356         struct vm_register *vmreg;
 357         struct vm_seg_desc *vmsegdesc;
 358         struct vm_register_set *vmregset;
 359         struct vm_run *vmrun;
 360         struct vm_exception *vmexc;
 361         struct vm_lapic_irq *vmirq;
 362         struct vm_lapic_msi *vmmsi;
 363         struct vm_ioapic_irq *ioapic_irq;
 364         struct vm_isa_irq *isa_irq;
 365         struct vm_isa_irq_trigger *isa_irq_trigger;
 366         struct vm_capability *vmcap;
 367         struct vm_pptdev *pptdev;
 368         struct vm_pptdev_mmio *pptmmio;
 369         struct vm_pptdev_msi *pptmsi;
 370         struct vm_pptdev_msix *pptmsix;
 371         struct vm_nmi *vmnmi;
 372         struct vm_stats *vmstats;
 373         struct vm_stat_desc *statdesc;
 374         struct vm_x2apic *x2apic;
 375         struct vm_gpa_pte *gpapte;
 376         struct vm_suspend *vmsuspend;
 377         struct vm_gla2gpa *gg;
 378         struct vm_activate_cpu *vac;
 379         struct vm_cpuset *vm_cpuset;
 380         struct vm_intinfo *vmii;
 381         struct vm_rtc_time *rtctime;
 382         struct vm_rtc_data *rtcdata;
 383         struct vm_memmap *mm;
 384         struct vm_cpu_topology *topology;
 385         struct vm_readwrite_kernemu_device *kernemu;
 386         uint64_t *regvals;
 387         int *regnums;
 388 #ifdef BHYVE_SNAPSHOT
 389         struct vm_snapshot_meta *snapshot_meta;
 390 #endif
 391
 392         error = vmm_priv_check(curthread->td_ucred);
 393         if (error)
 394                 return (error);
 395
 396         sc = vmmdev_lookup2(cdev);
 397         if (sc == NULL)
 398                 return (ENXIO);
 399
 400         vcpu = -1;
 401         state_changed = 0;
 402
 403         /*
 404          * Some VMM ioctls can operate only on vcpus that are not running.
 405          */
 406         switch (cmd) {
 407         case VM_RUN:
 408         case VM_GET_REGISTER:
 409         case VM_SET_REGISTER:
 410         case VM_GET_SEGMENT_DESCRIPTOR:
 411         case VM_SET_SEGMENT_DESCRIPTOR:
 412         case VM_GET_REGISTER_SET:
 413         case VM_SET_REGISTER_SET:
 414         case VM_INJECT_EXCEPTION:
 415         case VM_GET_CAPABILITY:
 416         case VM_SET_CAPABILITY:
 417         case VM_PPTDEV_MSI:
 418         case VM_PPTDEV_MSIX:
 419         case VM_SET_X2APIC_STATE:
 420         case VM_GLA2GPA:
 421         case VM_GLA2GPA_NOFAULT:
 422         case VM_ACTIVATE_CPU:
 423         case VM_SET_INTINFO:
 424         case VM_GET_INTINFO:
 425         case VM_RESTART_INSTRUCTION:
 426                 /*
 427                  * XXX fragile, handle with care
 428                  * Assumes that the first field of the ioctl data is the vcpu.
 429                  */
 430                 vcpu = *(int *)data;
 431                 error = vcpu_lock_one(sc, vcpu);
 432                 if (error)
 433                         goto done;
 434                 state_changed = 1;
 435                 break;
 436
 437         case VM_MAP_PPTDEV_MMIO:
 438         case VM_BIND_PPTDEV:
 439         case VM_UNBIND_PPTDEV:
 440 #ifdef COMPAT_FREEBSD12
 441         case VM_ALLOC_MEMSEG_FBSD12:
 442 #endif
 443         case VM_ALLOC_MEMSEG:
 444         case VM_MMAP_MEMSEG:
 445         case VM_REINIT:
 446                 /*
 447                  * ioctls that operate on the entire virtual machine must
 448                  * prevent all vcpus from running.
 449                  */
 450                 error = vcpu_lock_all(sc);
 451                 if (error)
 452                         goto done;
 453                 state_changed = 2;
 454                 break;
 455
 456 #ifdef COMPAT_FREEBSD12
 457         case VM_GET_MEMSEG_FBSD12:
 458 #endif
 459         case VM_GET_MEMSEG:
 460         case VM_MMAP_GETNEXT:
 461                 /*
 462                  * Lock a vcpu to make sure that the memory map cannot be
 463                  * modified while it is being inspected.
 464                  */
 465                 vcpu = vm_get_maxcpus(sc->vm) - 1;
 466                 error = vcpu_lock_one(sc, vcpu);
 467                 if (error)
 468                         goto done;
 469                 state_changed = 1;
 470                 break;
 471
 472         default:
 473                 break;
 474         }
 475
 476         switch(cmd) {
 477         case VM_RUN:
 478                 vmrun = (struct vm_run *)data;
 479                 error = vm_run(sc->vm, vmrun);
 480                 break;
 481         case VM_SUSPEND:
 482                 vmsuspend = (struct vm_suspend *)data;
 483                 error = vm_suspend(sc->vm, vmsuspend->how);
 484                 break;
 485         case VM_REINIT:
 486                 error = vm_reinit(sc->vm);
 487                 break;
 488         case VM_STAT_DESC: {
 489                 statdesc = (struct vm_stat_desc *)data;
 490                 error = vmm_stat_desc_copy(statdesc->index,
 491                                         statdesc->desc, sizeof(statdesc->desc));
 492                 break;
 493         }
 494         case VM_STATS: {
 495                 CTASSERT(MAX_VM_STATS >= MAX_VMM_STAT_ELEMS);
 496                 vmstats = (struct vm_stats *)data;
 497                 getmicrotime(&vmstats->tv);
 498                 error = vmm_stat_copy(sc->vm, vmstats->cpuid,
 499                                       &vmstats->num_entries, vmstats->statbuf);
 500                 break;
 501         }
 502         case VM_PPTDEV_MSI:
 503                 pptmsi = (struct vm_pptdev_msi *)data;
 504                 error = ppt_setup_msi(sc->vm, pptmsi->vcpu,
 505                                       pptmsi->bus, pptmsi->slot, pptmsi->func,
 506                                       pptmsi->addr, pptmsi->msg,
 507                                       pptmsi->numvec);
 508                 break;
 509         case VM_PPTDEV_MSIX:
 510                 pptmsix = (struct vm_pptdev_msix *)data;
 511                 error = ppt_setup_msix(sc->vm, pptmsix->vcpu,
 512                                        pptmsix->bus, pptmsix->slot,
 513                                        pptmsix->func, pptmsix->idx,
 514                                        pptmsix->addr, pptmsix->msg,
 515                                        pptmsix->vector_control);
 516                 break;
 517         case VM_MAP_PPTDEV_MMIO:
 518                 pptmmio = (struct vm_pptdev_mmio *)data;
 519                 error = ppt_map_mmio(sc->vm, pptmmio->bus, pptmmio->slot,
 520                                      pptmmio->func, pptmmio->gpa, pptmmio->len,
 521                                      pptmmio->hpa);
 522                 break;
 523         case VM_BIND_PPTDEV:
 524                 pptdev = (struct vm_pptdev *)data;
 525                 error = vm_assign_pptdev(sc->vm, pptdev->bus, pptdev->slot,
 526                                          pptdev->func);
 527                 break;
 528         case VM_UNBIND_PPTDEV:
 529                 pptdev = (struct vm_pptdev *)data;
 530                 error = vm_unassign_pptdev(sc->vm, pptdev->bus, pptdev->slot,
 531                                            pptdev->func);
 532                 break;
 533         case VM_INJECT_EXCEPTION:
 534                 vmexc = (struct vm_exception *)data;
 535                 error = vm_inject_exception(sc->vm, vmexc->cpuid,
 536                     vmexc->vector, vmexc->error_code_valid, vmexc->error_code,
 537                     vmexc->restart_instruction);
 538                 break;
 539         case VM_INJECT_NMI:
 540                 vmnmi = (struct vm_nmi *)data;
 541                 error = vm_inject_nmi(sc->vm, vmnmi->cpuid);
 542                 break;
 543         case VM_LAPIC_IRQ:
 544                 vmirq = (struct vm_lapic_irq *)data;
 545                 error = lapic_intr_edge(sc->vm, vmirq->cpuid, vmirq->vector);
 546                 break;
 547         case VM_LAPIC_LOCAL_IRQ:
 548                 vmirq = (struct vm_lapic_irq *)data;
 549                 error = lapic_set_local_intr(sc->vm, vmirq->cpuid,
 550                     vmirq->vector);
 551                 break;
 552         case VM_LAPIC_MSI:
 553                 vmmsi = (struct vm_lapic_msi *)data;
 554                 error = lapic_intr_msi(sc->vm, vmmsi->addr, vmmsi->msg);
 555                 break;
 556         case VM_IOAPIC_ASSERT_IRQ:
 557                 ioapic_irq = (struct vm_ioapic_irq *)data;
 558                 error = vioapic_assert_irq(sc->vm, ioapic_irq->irq);
 559                 break;
 560         case VM_IOAPIC_DEASSERT_IRQ:
 561                 ioapic_irq = (struct vm_ioapic_irq *)data;
 562                 error = vioapic_deassert_irq(sc->vm, ioapic_irq->irq);
 563                 break;
 564         case VM_IOAPIC_PULSE_IRQ:
 565                 ioapic_irq = (struct vm_ioapic_irq *)data;
 566                 error = vioapic_pulse_irq(sc->vm, ioapic_irq->irq);
 567                 break;
 568         case VM_IOAPIC_PINCOUNT:
 569                 *(int *)data = vioapic_pincount(sc->vm);
 570                 break;
 571         case VM_SET_KERNEMU_DEV:
 572         case VM_GET_KERNEMU_DEV: {
 573                 mem_region_write_t mwrite;
 574                 mem_region_read_t mread;
 575                 bool arg;
 576
 577                 kernemu = (void *)data;
 578
 579                 if (kernemu->access_width > 0)
 580                         size = (1u << kernemu->access_width);
 581                 else
 582                         size = 1;
 583
 584                 if (kernemu->gpa >= DEFAULT_APIC_BASE && kernemu->gpa < DEFAULT_APIC_BASE + PAGE_SIZE) {
 585                         mread = lapic_mmio_read;
 586                         mwrite = lapic_mmio_write;
 587                 } else if (kernemu->gpa >= VIOAPIC_BASE && kernemu->gpa < VIOAPIC_BASE + VIOAPIC_SIZE) {
 588                         mread = vioapic_mmio_read;
 589                         mwrite = vioapic_mmio_write;
 590                 } else if (kernemu->gpa >= VHPET_BASE && kernemu->gpa < VHPET_BASE + VHPET_SIZE) {
 591                         mread = vhpet_mmio_read;
 592                         mwrite = vhpet_mmio_write;
 593                 } else {
 594                         error = EINVAL;
 595                         break;
 596                 }
 597
 598                 if (cmd == VM_SET_KERNEMU_DEV)
 599                         error = mwrite(sc->vm, kernemu->vcpuid, kernemu->gpa,
 600                             kernemu->value, size, &arg);
 601                 else
 602                         error = mread(sc->vm, kernemu->vcpuid, kernemu->gpa,
 603                             &kernemu->value, size, &arg);
 604                 break;
 605                 }
 606         case VM_ISA_ASSERT_IRQ:
 607                 isa_irq = (struct vm_isa_irq *)data;
 608                 error = vatpic_assert_irq(sc->vm, isa_irq->atpic_irq);
 609                 if (error == 0 && isa_irq->ioapic_irq != -1)
 610                         error = vioapic_assert_irq(sc->vm,
 611                             isa_irq->ioapic_irq);
 612                 break;
 613         case VM_ISA_DEASSERT_IRQ:
 614                 isa_irq = (struct vm_isa_irq *)data;
 615                 error = vatpic_deassert_irq(sc->vm, isa_irq->atpic_irq);
 616                 if (error == 0 && isa_irq->ioapic_irq != -1)
 617                         error = vioapic_deassert_irq(sc->vm,
 618                             isa_irq->ioapic_irq);
 619                 break;
 620         case VM_ISA_PULSE_IRQ:
 621                 isa_irq = (struct vm_isa_irq *)data;
 622                 error = vatpic_pulse_irq(sc->vm, isa_irq->atpic_irq);
 623                 if (error == 0 && isa_irq->ioapic_irq != -1)
 624                         error = vioapic_pulse_irq(sc->vm, isa_irq->ioapic_irq);
 625                 break;
 626         case VM_ISA_SET_IRQ_TRIGGER:
 627                 isa_irq_trigger = (struct vm_isa_irq_trigger *)data;
 628                 error = vatpic_set_irq_trigger(sc->vm,
 629                     isa_irq_trigger->atpic_irq, isa_irq_trigger->trigger);
 630                 break;
 631         case VM_MMAP_GETNEXT:
 632                 mm = (struct vm_memmap *)data;
 633                 error = vm_mmap_getnext(sc->vm, &mm->gpa, &mm->segid,
 634                     &mm->segoff, &mm->len, &mm->prot, &mm->flags);
 635                 break;
 636         case VM_MMAP_MEMSEG:
 637                 mm = (struct vm_memmap *)data;
 638                 error = vm_mmap_memseg(sc->vm, mm->gpa, mm->segid, mm->segoff,
 639                     mm->len, mm->prot, mm->flags);
 640                 break;
 641 #ifdef COMPAT_FREEBSD12
 642         case VM_ALLOC_MEMSEG_FBSD12:
 643                 error = alloc_memseg(sc, (struct vm_memseg *)data,
 644                     sizeof(((struct vm_memseg_fbsd12 *)0)->name));
 645                 break;
 646 #endif
 647         case VM_ALLOC_MEMSEG:
 648                 error = alloc_memseg(sc, (struct vm_memseg *)data,
 649                     sizeof(((struct vm_memseg *)0)->name));
 650                 break;
 651 #ifdef COMPAT_FREEBSD12
 652         case VM_GET_MEMSEG_FBSD12:
 653                 error = get_memseg(sc, (struct vm_memseg *)data,
 654                     sizeof(((struct vm_memseg_fbsd12 *)0)->name));
 655                 break;
 656 #endif
 657         case VM_GET_MEMSEG:
 658                 error = get_memseg(sc, (struct vm_memseg *)data,
 659                     sizeof(((struct vm_memseg *)0)->name));
 660                 break;
 661         case VM_GET_REGISTER:
 662                 vmreg = (struct vm_register *)data;
 663                 error = vm_get_register(sc->vm, vmreg->cpuid, vmreg->regnum,
 664                                         &vmreg->regval);
 665                 break;
 666         case VM_SET_REGISTER:
 667                 vmreg = (struct vm_register *)data;
 668                 error = vm_set_register(sc->vm, vmreg->cpuid, vmreg->regnum,
 669                                         vmreg->regval);
 670                 break;
 671         case VM_SET_SEGMENT_DESCRIPTOR:
 672                 vmsegdesc = (struct vm_seg_desc *)data;
 673                 error = vm_set_seg_desc(sc->vm, vmsegdesc->cpuid,
 674                                         vmsegdesc->regnum,
 675                                         &vmsegdesc->desc);
 676                 break;
 677         case VM_GET_SEGMENT_DESCRIPTOR:
 678                 vmsegdesc = (struct vm_seg_desc *)data;
 679                 error = vm_get_seg_desc(sc->vm, vmsegdesc->cpuid,
 680                                         vmsegdesc->regnum,
 681                                         &vmsegdesc->desc);
 682                 break;
 683         case VM_GET_REGISTER_SET:
 684                 vmregset = (struct vm_register_set *)data;
 685                 if (vmregset->count > VM_REG_LAST) {
 686                         error = EINVAL;
 687                         break;
 688                 }
 689                 regvals = malloc(sizeof(regvals[0]) * vmregset->count, M_VMMDEV,
 690                     M_WAITOK);
 691                 regnums = malloc(sizeof(regnums[0]) * vmregset->count, M_VMMDEV,
 692                     M_WAITOK);
 693                 error = copyin(vmregset->regnums, regnums, sizeof(regnums[0]) *
 694                     vmregset->count);
 695                 if (error == 0)
 696                         error = vm_get_register_set(sc->vm, vmregset->cpuid,
 697                             vmregset->count, regnums, regvals);
 698                 if (error == 0)
 699                         error = copyout(regvals, vmregset->regvals,
 700                             sizeof(regvals[0]) * vmregset->count);
 701                 free(regvals, M_VMMDEV);
 702                 free(regnums, M_VMMDEV);
 703                 break;
 704         case VM_SET_REGISTER_SET:
 705                 vmregset = (struct vm_register_set *)data;
 706                 if (vmregset->count > VM_REG_LAST) {
 707                         error = EINVAL;
 708                         break;
 709                 }
 710                 regvals = malloc(sizeof(regvals[0]) * vmregset->count, M_VMMDEV,
 711                     M_WAITOK);
 712                 regnums = malloc(sizeof(regnums[0]) * vmregset->count, M_VMMDEV,
 713                     M_WAITOK);
 714                 error = copyin(vmregset->regnums, regnums, sizeof(regnums[0]) *
 715                     vmregset->count);
 716                 if (error == 0)
 717                         error = copyin(vmregset->regvals, regvals,
 718                             sizeof(regvals[0]) * vmregset->count);
 719                 if (error == 0)
 720                         error = vm_set_register_set(sc->vm, vmregset->cpuid,
 721                             vmregset->count, regnums, regvals);
 722                 free(regvals, M_VMMDEV);
 723                 free(regnums, M_VMMDEV);
 724                 break;
 725         case VM_GET_CAPABILITY:
 726                 vmcap = (struct vm_capability *)data;
 727                 error = vm_get_capability(sc->vm, vmcap->cpuid,
 728                                           vmcap->captype,
 729                                           &vmcap->capval);
 730                 break;
 731         case VM_SET_CAPABILITY:
 732                 vmcap = (struct vm_capability *)data;
 733                 error = vm_set_capability(sc->vm, vmcap->cpuid,
 734                                           vmcap->captype,
 735                                           vmcap->capval);
 736                 break;
 737         case VM_SET_X2APIC_STATE:
 738                 x2apic = (struct vm_x2apic *)data;
 739                 error = vm_set_x2apic_state(sc->vm,
 740                                             x2apic->cpuid, x2apic->state);
 741                 break;
 742         case VM_GET_X2APIC_STATE:
 743                 x2apic = (struct vm_x2apic *)data;
 744                 error = vm_get_x2apic_state(sc->vm,
 745                                             x2apic->cpuid, &x2apic->state);
 746                 break;
 747         case VM_GET_GPA_PMAP:
 748                 gpapte = (struct vm_gpa_pte *)data;
 749                 pmap_get_mapping(vmspace_pmap(vm_get_vmspace(sc->vm)),
 750                                  gpapte->gpa, gpapte->pte, &gpapte->ptenum);
 751                 error = 0;
 752                 break;
 753         case VM_GET_HPET_CAPABILITIES:
 754                 error = vhpet_getcap((struct vm_hpet_cap *)data);
 755                 break;
 756         case VM_GLA2GPA: {
 757                 CTASSERT(PROT_READ == VM_PROT_READ);
 758                 CTASSERT(PROT_WRITE == VM_PROT_WRITE);
 759                 CTASSERT(PROT_EXEC == VM_PROT_EXECUTE);
 760                 gg = (struct vm_gla2gpa *)data;
 761                 error = vm_gla2gpa(sc->vm, gg->vcpuid, &gg->paging, gg->gla,
 762                     gg->prot, &gg->gpa, &gg->fault);
 763                 KASSERT(error == 0 || error == EFAULT,
 764                     ("%s: vm_gla2gpa unknown error %d", __func__, error));
 765                 break;
 766         }
 767         case VM_GLA2GPA_NOFAULT:
 768                 gg = (struct vm_gla2gpa *)data;
 769                 error = vm_gla2gpa_nofault(sc->vm, gg->vcpuid, &gg->paging,
 770                     gg->gla, gg->prot, &gg->gpa, &gg->fault);
 771                 KASSERT(error == 0 || error == EFAULT,
 772                     ("%s: vm_gla2gpa unknown error %d", __func__, error));
 773                 break;
 774         case VM_ACTIVATE_CPU:
 775                 vac = (struct vm_activate_cpu *)data;
 776                 error = vm_activate_cpu(sc->vm, vac->vcpuid);
 777                 break;
 778         case VM_GET_CPUS:
 779                 error = 0;
 780                 vm_cpuset = (struct vm_cpuset *)data;
 781                 size = vm_cpuset->cpusetsize;
 782                 if (size < sizeof(cpuset_t) || size > CPU_MAXSIZE / NBBY) {
 783                         error = ERANGE;
 784                         break;
 785                 }
 786                 cpuset = malloc(size, M_TEMP, M_WAITOK | M_ZERO);
 787                 if (vm_cpuset->which == VM_ACTIVE_CPUS)
 788                         *cpuset = vm_active_cpus(sc->vm);
 789                 else if (vm_cpuset->which == VM_SUSPENDED_CPUS)
 790                         *cpuset = vm_suspended_cpus(sc->vm);
 791                 else if (vm_cpuset->which == VM_DEBUG_CPUS)
 792                         *cpuset = vm_debug_cpus(sc->vm);
 793                 else
 794                         error = EINVAL;
 795                 if (error == 0)
 796                         error = copyout(cpuset, vm_cpuset->cpus, size);
 797                 free(cpuset, M_TEMP);
 798                 break;
 799         case VM_SUSPEND_CPU:
 800                 vac = (struct vm_activate_cpu *)data;
 801                 error = vm_suspend_cpu(sc->vm, vac->vcpuid);
 802                 break;
 803         case VM_RESUME_CPU:
 804                 vac = (struct vm_activate_cpu *)data;
 805                 error = vm_resume_cpu(sc->vm, vac->vcpuid);
 806                 break;
 807         case VM_SET_INTINFO:
 808                 vmii = (struct vm_intinfo *)data;
 809                 error = vm_exit_intinfo(sc->vm, vmii->vcpuid, vmii->info1);
 810                 break;
 811         case VM_GET_INTINFO:
 812                 vmii = (struct vm_intinfo *)data;
 813                 error = vm_get_intinfo(sc->vm, vmii->vcpuid, &vmii->info1,
 814                     &vmii->info2);
 815                 break;
 816         case VM_RTC_WRITE:
 817                 rtcdata = (struct vm_rtc_data *)data;
 818                 error = vrtc_nvram_write(sc->vm, rtcdata->offset,
 819                     rtcdata->value);
 820                 break;
 821         case VM_RTC_READ:
 822                 rtcdata = (struct vm_rtc_data *)data;
 823                 error = vrtc_nvram_read(sc->vm, rtcdata->offset,
 824                     &rtcdata->value);
 825                 break;
 826         case VM_RTC_SETTIME:
 827                 rtctime = (struct vm_rtc_time *)data;
 828                 error = vrtc_set_time(sc->vm, rtctime->secs);
 829                 break;
 830         case VM_RTC_GETTIME:
 831                 error = 0;
 832                 rtctime = (struct vm_rtc_time *)data;
 833                 rtctime->secs = vrtc_get_time(sc->vm);
 834                 break;
 835         case VM_RESTART_INSTRUCTION:
 836                 error = vm_restart_instruction(sc->vm, vcpu);
 837                 break;
 838         case VM_SET_TOPOLOGY:
 839                 topology = (struct vm_cpu_topology *)data;
 840                 error = vm_set_topology(sc->vm, topology->sockets,
 841                     topology->cores, topology->threads, topology->maxcpus);
 842                 break;
 843         case VM_GET_TOPOLOGY:
 844                 topology = (struct vm_cpu_topology *)data;
 845                 vm_get_topology(sc->vm, &topology->sockets, &topology->cores,
 846                     &topology->threads, &topology->maxcpus);
 847                 error = 0;
 848                 break;
 849 #ifdef BHYVE_SNAPSHOT
 850         case VM_SNAPSHOT_REQ:
 851                 snapshot_meta = (struct vm_snapshot_meta *)data;
 852                 error = vm_snapshot_req(sc->vm, snapshot_meta);
 853                 break;
 854         case VM_RESTORE_TIME:
 855                 error = vm_restore_time(sc->vm);
 856                 break;
 857 #endif
 858         default:
 859                 error = ENOTTY;
 860                 break;
 861         }
 862
 863         if (state_changed == 1)
 864                 vcpu_unlock_one(sc, vcpu);
 865         else if (state_changed == 2)
 866                 vcpu_unlock_all(sc);
 867
 868 done:
 869         /*
 870          * Make sure that no handler returns a kernel-internal
 871          * error value to userspace.
 872          */
 873         KASSERT(error == ERESTART || error >= 0,
 874             ("vmmdev_ioctl: invalid error return %d", error));
 875         return (error);
 876 }
 877
 878 static int
 879 vmmdev_mmap_single(struct cdev *cdev, vm_ooffset_t *offset, vm_size_t mapsize,
 880     struct vm_object **objp, int nprot)
 881 {
 882         struct vmmdev_softc *sc;
 883         vm_paddr_t gpa;
 884         size_t len;
 885         vm_ooffset_t segoff, first, last;
 886         int error, found, segid;
 887         uint16_t lastcpu;
 888         bool sysmem;
 889
 890         error = vmm_priv_check(curthread->td_ucred);
 891         if (error)
 892                 return (error);
 893
 894         first = *offset;
 895         last = first + mapsize;
 896         if ((nprot & PROT_EXEC) || first < 0 || first >= last)
 897                 return (EINVAL);
 898
 899         sc = vmmdev_lookup2(cdev);
 900         if (sc == NULL) {
 901                 /* virtual machine is in the process of being created */
 902                 return (EINVAL);
 903         }
 904
 905         /*
 906          * Get a read lock on the guest memory map by freezing any vcpu.
 907          */
 908         lastcpu = vm_get_maxcpus(sc->vm) - 1;
 909         error = vcpu_lock_one(sc, lastcpu);
 910         if (error)
 911                 return (error);
 912
 913         gpa = 0;
 914         found = 0;
 915         while (!found) {
 916                 error = vm_mmap_getnext(sc->vm, &gpa, &segid, &segoff, &len,
 917                     NULL, NULL);
 918                 if (error)
 919                         break;
 920
 921                 if (first >= gpa && last <= gpa + len)
 922                         found = 1;
 923                 else
 924                         gpa += len;
 925         }
 926
 927         if (found) {
 928                 error = vm_get_memseg(sc->vm, segid, &len, &sysmem, objp);
 929                 KASSERT(error == 0 && *objp != NULL,
 930                     ("%s: invalid memory segment %d", __func__, segid));
 931                 if (sysmem) {
 932                         vm_object_reference(*objp);
 933                         *offset = segoff + (first - gpa);
 934                 } else {
 935                         error = EINVAL;
 936                 }
 937         }
 938         vcpu_unlock_one(sc, lastcpu);
 939         return (error);
 940 }
 941
 942 static void
 943 vmmdev_destroy(void *arg)
 944 {
 945         struct vmmdev_softc *sc = arg;
 946         struct devmem_softc *dsc;
 947         int error;
 948
 949         error = vcpu_lock_all(sc);
 950         KASSERT(error == 0, ("%s: error %d freezing vcpus", __func__, error));
 951
 952         while ((dsc = SLIST_FIRST(&sc->devmem)) != NULL) {
 953                 KASSERT(dsc->cdev == NULL, ("%s: devmem not free", __func__));
 954                 SLIST_REMOVE_HEAD(&sc->devmem, link);
 955                 free(dsc->name, M_VMMDEV);
 956                 free(dsc, M_VMMDEV);
 957         }
 958
 959         if (sc->cdev != NULL)
 960                 destroy_dev(sc->cdev);
 961
 962         if (sc->vm != NULL)
 963                 vm_destroy(sc->vm);
 964
 965         if ((sc->flags & VSC_LINKED) != 0) {
 966                 mtx_lock(&vmmdev_mtx);
 967                 SLIST_REMOVE(&head, sc, vmmdev_softc, link);
 968                 mtx_unlock(&vmmdev_mtx);
 969         }
 970
 971         free(sc, M_VMMDEV);
 972 }
 973
 974 static int
 975 sysctl_vmm_destroy(SYSCTL_HANDLER_ARGS)
 976 {
 977         struct devmem_softc *dsc;
 978         struct vmmdev_softc *sc;
 979         struct cdev *cdev;
 980         char *buf;
 981         int error, buflen;
 982
 983         error = vmm_priv_check(req->td->td_ucred);
 984         if (error)
 985                 return (error);
 986
 987         buflen = VM_MAX_NAMELEN + 1;
 988         buf = malloc(buflen, M_VMMDEV, M_WAITOK | M_ZERO);
 989         strlcpy(buf, "beavis", buflen);
 990         error = sysctl_handle_string(oidp, buf, buflen, req);
 991         if (error != 0 || req->newptr == NULL)
 992                 goto out;
 993
 994         mtx_lock(&vmmdev_mtx);
 995         sc = vmmdev_lookup(buf);
 996         if (sc == NULL || sc->cdev == NULL) {
 997                 mtx_unlock(&vmmdev_mtx);
 998                 error = EINVAL;
 999                 goto out;
1000         }
1001
1002         /*
1003          * The 'cdev' will be destroyed asynchronously when 'si_threadcount'
1004          * goes down to 0 so we should not do it again in the callback.
1005          *
1006          * Setting 'sc->cdev' to NULL is also used to indicate that the VM
1007          * is scheduled for destruction.
1008          */
1009         cdev = sc->cdev;
1010         sc->cdev = NULL;
1011         mtx_unlock(&vmmdev_mtx);
1012
1013         /*
1014          * Schedule all cdevs to be destroyed:
1015          *
1016          * - any new operations on the 'cdev' will return an error (ENXIO).
1017          *
1018          * - when the 'si_threadcount' dwindles down to zero the 'cdev' will
1019          *   be destroyed and the callback will be invoked in a taskqueue
1020          *   context.
1021          *
1022          * - the 'devmem' cdevs are destroyed before the virtual machine 'cdev'
1023          */
1024         SLIST_FOREACH(dsc, &sc->devmem, link) {
1025                 KASSERT(dsc->cdev != NULL, ("devmem cdev already destroyed"));
1026                 destroy_dev_sched_cb(dsc->cdev, devmem_destroy, dsc);
1027         }
1028         destroy_dev_sched_cb(cdev, vmmdev_destroy, sc);
1029         error = 0;
1030
1031 out:
1032         free(buf, M_VMMDEV);
1033         return (error);
1034 }
1035 SYSCTL_PROC(_hw_vmm, OID_AUTO, destroy,
1036     CTLTYPE_STRING | CTLFLAG_RW | CTLFLAG_PRISON | CTLFLAG_MPSAFE,
1037     NULL, 0, sysctl_vmm_destroy, "A",
1038     NULL);
1039
1040 static struct cdevsw vmmdevsw = {
1041         .d_name         = "vmmdev",
1042         .d_version      = D_VERSION,
1043         .d_ioctl        = vmmdev_ioctl,
1044         .d_mmap_single  = vmmdev_mmap_single,
1045         .d_read         = vmmdev_rw,
1046         .d_write        = vmmdev_rw,
1047 };
1048
1049 static int
1050 sysctl_vmm_create(SYSCTL_HANDLER_ARGS)
1051 {
1052         struct vm *vm;
1053         struct cdev *cdev;
1054         struct vmmdev_softc *sc, *sc2;
1055         char *buf;
1056         int error, buflen;
1057
1058         error = vmm_priv_check(req->td->td_ucred);
1059         if (error)
1060                 return (error);
1061
1062         buflen = VM_MAX_NAMELEN + 1;
1063         buf = malloc(buflen, M_VMMDEV, M_WAITOK | M_ZERO);
1064         strlcpy(buf, "beavis", buflen);
1065         error = sysctl_handle_string(oidp, buf, buflen, req);
1066         if (error != 0 || req->newptr == NULL)
1067                 goto out;
1068
1069         mtx_lock(&vmmdev_mtx);
1070         sc = vmmdev_lookup(buf);
1071         mtx_unlock(&vmmdev_mtx);
1072         if (sc != NULL) {
1073                 error = EEXIST;
1074                 goto out;
1075         }
1076
1077         error = vm_create(buf, &vm);
1078         if (error != 0)
1079                 goto out;
1080
1081         sc = malloc(sizeof(struct vmmdev_softc), M_VMMDEV, M_WAITOK | M_ZERO);
1082         sc->vm = vm;
1083         SLIST_INIT(&sc->devmem);
1084
1085         /*
1086          * Lookup the name again just in case somebody sneaked in when we
1087          * dropped the lock.
1088          */
1089         mtx_lock(&vmmdev_mtx);
1090         sc2 = vmmdev_lookup(buf);
1091         if (sc2 == NULL) {
1092                 SLIST_INSERT_HEAD(&head, sc, link);
1093                 sc->flags |= VSC_LINKED;
1094         }
1095         mtx_unlock(&vmmdev_mtx);
1096
1097         if (sc2 != NULL) {
1098                 vmmdev_destroy(sc);
1099                 error = EEXIST;
1100                 goto out;
1101         }
1102
1103         error = make_dev_p(MAKEDEV_CHECKNAME, &cdev, &vmmdevsw, NULL,
1104                            UID_ROOT, GID_WHEEL, 0600, "vmm/%s", buf);
1105         if (error != 0) {
1106                 vmmdev_destroy(sc);
1107                 goto out;
1108         }
1109
1110         mtx_lock(&vmmdev_mtx);
1111         sc->cdev = cdev;
1112         sc->cdev->si_drv1 = sc;
1113         mtx_unlock(&vmmdev_mtx);
1114
1115 out:
1116         free(buf, M_VMMDEV);
1117         return (error);
1118 }
1119 SYSCTL_PROC(_hw_vmm, OID_AUTO, create,
1120     CTLTYPE_STRING | CTLFLAG_RW | CTLFLAG_PRISON | CTLFLAG_MPSAFE,
1121     NULL, 0, sysctl_vmm_create, "A",
1122     NULL);
1123
1124 void
1125 vmmdev_init(void)
1126 {
1127         mtx_init(&vmmdev_mtx, "vmm device mutex", NULL, MTX_DEF);
1128         pr_allow_flag = prison_add_allow(NULL, "vmm", NULL,
1129             "Allow use of vmm in a jail.");
1130 }
1131
1132 int
1133 vmmdev_cleanup(void)
1134 {
1135         int error;
1136
1137         if (SLIST_EMPTY(&head))
1138                 error = 0;
1139         else
1140                 error = EBUSY;
1141
1142         return (error);
1143 }
1144
1145 static int
1146 devmem_mmap_single(struct cdev *cdev, vm_ooffset_t *offset, vm_size_t len,
1147     struct vm_object **objp, int nprot)
1148 {
1149         struct devmem_softc *dsc;
1150         vm_ooffset_t first, last;
1151         size_t seglen;
1152         int error;
1153         uint16_t lastcpu;
1154         bool sysmem;
1155
1156         dsc = cdev->si_drv1;
1157         if (dsc == NULL) {
1158                 /* 'cdev' has been created but is not ready for use */
1159                 return (ENXIO);
1160         }
1161
1162         first = *offset;
1163         last = *offset + len;
1164         if ((nprot & PROT_EXEC) || first < 0 || first >= last)
1165                 return (EINVAL);
1166
1167         lastcpu = vm_get_maxcpus(dsc->sc->vm) - 1;
1168         error = vcpu_lock_one(dsc->sc, lastcpu);
1169         if (error)
1170                 return (error);
1171
1172         error = vm_get_memseg(dsc->sc->vm, dsc->segid, &seglen, &sysmem, objp);
1173         KASSERT(error == 0 && !sysmem && *objp != NULL,
1174             ("%s: invalid devmem segment %d", __func__, dsc->segid));
1175
1176         vcpu_unlock_one(dsc->sc, lastcpu);
1177
1178         if (seglen >= last) {
1179                 vm_object_reference(*objp);
1180                 return (0);
1181         } else {
1182                 return (EINVAL);
1183         }
1184 }
1185
1186 static struct cdevsw devmemsw = {
1187         .d_name         = "devmem",
1188         .d_version      = D_VERSION,
1189         .d_mmap_single  = devmem_mmap_single,
1190 };
1191
1192 static int
1193 devmem_create_cdev(const char *vmname, int segid, char *devname)
1194 {
1195         struct devmem_softc *dsc;
1196         struct vmmdev_softc *sc;
1197         struct cdev *cdev;
1198         int error;
1199
1200         error = make_dev_p(MAKEDEV_CHECKNAME, &cdev, &devmemsw, NULL,
1201             UID_ROOT, GID_WHEEL, 0600, "vmm.io/%s.%s", vmname, devname);
1202         if (error)
1203                 return (error);
1204
1205         dsc = malloc(sizeof(struct devmem_softc), M_VMMDEV, M_WAITOK | M_ZERO);
1206
1207         mtx_lock(&vmmdev_mtx);
1208         sc = vmmdev_lookup(vmname);
1209         KASSERT(sc != NULL, ("%s: vm %s softc not found", __func__, vmname));
1210         if (sc->cdev == NULL) {
1211                 /* virtual machine is being created or destroyed */
1212                 mtx_unlock(&vmmdev_mtx);
1213                 free(dsc, M_VMMDEV);
1214                 destroy_dev_sched_cb(cdev, NULL, 0);
1215                 return (ENODEV);
1216         }
1217
1218         dsc->segid = segid;
1219         dsc->name = devname;
1220         dsc->cdev = cdev;
1221         dsc->sc = sc;
1222         SLIST_INSERT_HEAD(&sc->devmem, dsc, link);
1223         mtx_unlock(&vmmdev_mtx);
1224
1225         /* The 'cdev' is ready for use after 'si_drv1' is initialized */
1226         cdev->si_drv1 = dsc;
1227         return (0);
1228 }
1229
1230 static void
1231 devmem_destroy(void *arg)
1232 {
1233         struct devmem_softc *dsc = arg;
1234
1235         KASSERT(dsc->cdev, ("%s: devmem cdev already destroyed", __func__));
1236         dsc->cdev = NULL;
1237         dsc->sc = NULL;
1238 }