xref: /freebsd-13.1/sys/amd64/vmm/vmm_dev.c (revision 2d4c599e)
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 	struct ucred	*ucred;
84 	SLIST_ENTRY(vmmdev_softc) link;
85 	SLIST_HEAD(, devmem_softc) devmem;
86 	int		flags;
87 };
88 #define	VSC_LINKED		0x01
89 
90 static SLIST_HEAD(, vmmdev_softc) head;
91 
92 static unsigned pr_allow_flag;
93 static struct mtx vmmdev_mtx;
94 
95 static MALLOC_DEFINE(M_VMMDEV, "vmmdev", "vmmdev");
96 
97 SYSCTL_DECL(_hw_vmm);
98 
99 static int vmm_priv_check(struct ucred *ucred);
100 static int devmem_create_cdev(const char *vmname, int id, char *devmem);
101 static void devmem_destroy(void *arg);
102 
103 static int
vmm_priv_check(struct ucred * ucred)104 vmm_priv_check(struct ucred *ucred)
105 {
106 
107 	if (jailed(ucred) &&
108 	    !(ucred->cr_prison->pr_allow & pr_allow_flag))
109 		return (EPERM);
110 
111 	return (0);
112 }
113 
114 static int
vcpu_lock_one(struct vmmdev_softc * sc,int vcpu)115 vcpu_lock_one(struct vmmdev_softc *sc, int vcpu)
116 {
117 	int error;
118 
119 	if (vcpu < 0 || vcpu >= vm_get_maxcpus(sc->vm))
120 		return (EINVAL);
121 
122 	error = vcpu_set_state(sc->vm, vcpu, VCPU_FROZEN, true);
123 	return (error);
124 }
125 
126 static void
vcpu_unlock_one(struct vmmdev_softc * sc,int vcpu)127 vcpu_unlock_one(struct vmmdev_softc *sc, int vcpu)
128 {
129 	enum vcpu_state state;
130 
131 	state = vcpu_get_state(sc->vm, vcpu, NULL);
132 	if (state != VCPU_FROZEN) {
133 		panic("vcpu %s(%d) has invalid state %d", vm_name(sc->vm),
134 		    vcpu, state);
135 	}
136 
137 	vcpu_set_state(sc->vm, vcpu, VCPU_IDLE, false);
138 }
139 
140 static int
vcpu_lock_all(struct vmmdev_softc * sc)141 vcpu_lock_all(struct vmmdev_softc *sc)
142 {
143 	int error, vcpu;
144 	uint16_t maxcpus;
145 
146 	maxcpus = vm_get_maxcpus(sc->vm);
147 	for (vcpu = 0; vcpu < maxcpus; vcpu++) {
148 		error = vcpu_lock_one(sc, vcpu);
149 		if (error)
150 			break;
151 	}
152 
153 	if (error) {
154 		while (--vcpu >= 0)
155 			vcpu_unlock_one(sc, vcpu);
156 	}
157 
158 	return (error);
159 }
160 
161 static void
vcpu_unlock_all(struct vmmdev_softc * sc)162 vcpu_unlock_all(struct vmmdev_softc *sc)
163 {
164 	int vcpu;
165 	uint16_t maxcpus;
166 
167 	maxcpus = vm_get_maxcpus(sc->vm);
168 	for (vcpu = 0; vcpu < maxcpus; vcpu++)
169 		vcpu_unlock_one(sc, vcpu);
170 }
171 
172 static struct vmmdev_softc *
vmmdev_lookup(const char * name)173 vmmdev_lookup(const char *name)
174 {
175 	struct vmmdev_softc *sc;
176 
177 #ifdef notyet	/* XXX kernel is not compiled with invariants */
178 	mtx_assert(&vmmdev_mtx, MA_OWNED);
179 #endif
180 
181 	SLIST_FOREACH(sc, &head, link) {
182 		if (strcmp(name, vm_name(sc->vm)) == 0)
183 			break;
184 	}
185 
186 	if (sc == NULL)
187 		return (NULL);
188 
189 	if (cr_cansee(curthread->td_ucred, sc->ucred))
190 		return (NULL);
191 
192 	return (sc);
193 }
194 
195 static struct vmmdev_softc *
vmmdev_lookup2(struct cdev * cdev)196 vmmdev_lookup2(struct cdev *cdev)
197 {
198 
199 	return (cdev->si_drv1);
200 }
201 
202 static int
vmmdev_rw(struct cdev * cdev,struct uio * uio,int flags)203 vmmdev_rw(struct cdev *cdev, struct uio *uio, int flags)
204 {
205 	int error, off, c, prot;
206 	vm_paddr_t gpa, maxaddr;
207 	void *hpa, *cookie;
208 	struct vmmdev_softc *sc;
209 	uint16_t lastcpu;
210 
211 	error = vmm_priv_check(curthread->td_ucred);
212 	if (error)
213 		return (error);
214 
215 	sc = vmmdev_lookup2(cdev);
216 	if (sc == NULL)
217 		return (ENXIO);
218 
219 	/*
220 	 * Get a read lock on the guest memory map by freezing any vcpu.
221 	 */
222 	lastcpu = vm_get_maxcpus(sc->vm) - 1;
223 	error = vcpu_lock_one(sc, lastcpu);
224 	if (error)
225 		return (error);
226 
227 	prot = (uio->uio_rw == UIO_WRITE ? VM_PROT_WRITE : VM_PROT_READ);
228 	maxaddr = vmm_sysmem_maxaddr(sc->vm);
229 	while (uio->uio_resid > 0 && error == 0) {
230 		gpa = uio->uio_offset;
231 		off = gpa & PAGE_MASK;
232 		c = min(uio->uio_resid, PAGE_SIZE - off);
233 
234 		/*
235 		 * The VM has a hole in its physical memory map. If we want to
236 		 * use 'dd' to inspect memory beyond the hole we need to
237 		 * provide bogus data for memory that lies in the hole.
238 		 *
239 		 * Since this device does not support lseek(2), dd(1) will
240 		 * read(2) blocks of data to simulate the lseek(2).
241 		 */
242 		hpa = vm_gpa_hold(sc->vm, lastcpu, gpa, c,
243 		    prot, &cookie);
244 		if (hpa == NULL) {
245 			if (uio->uio_rw == UIO_READ && gpa < maxaddr)
246 				error = uiomove(__DECONST(void *, zero_region),
247 				    c, uio);
248 			else
249 				error = EFAULT;
250 		} else {
251 			error = uiomove(hpa, c, uio);
252 			vm_gpa_release(cookie);
253 		}
254 	}
255 	vcpu_unlock_one(sc, lastcpu);
256 	return (error);
257 }
258 
259 CTASSERT(sizeof(((struct vm_memseg *)0)->name) >= VM_MAX_SUFFIXLEN + 1);
260 
261 static int
get_memseg(struct vmmdev_softc * sc,struct vm_memseg * mseg,size_t len)262 get_memseg(struct vmmdev_softc *sc, struct vm_memseg *mseg, size_t len)
263 {
264 	struct devmem_softc *dsc;
265 	int error;
266 	bool sysmem;
267 
268 	error = vm_get_memseg(sc->vm, mseg->segid, &mseg->len, &sysmem, NULL);
269 	if (error || mseg->len == 0)
270 		return (error);
271 
272 	if (!sysmem) {
273 		SLIST_FOREACH(dsc, &sc->devmem, link) {
274 			if (dsc->segid == mseg->segid)
275 				break;
276 		}
277 		KASSERT(dsc != NULL, ("%s: devmem segment %d not found",
278 		    __func__, mseg->segid));
279 		error = copystr(dsc->name, mseg->name, len, NULL);
280 	} else {
281 		bzero(mseg->name, len);
282 	}
283 
284 	return (error);
285 }
286 
287 static int
alloc_memseg(struct vmmdev_softc * sc,struct vm_memseg * mseg,size_t len)288 alloc_memseg(struct vmmdev_softc *sc, struct vm_memseg *mseg, size_t len)
289 {
290 	char *name;
291 	int error;
292 	bool sysmem;
293 
294 	error = 0;
295 	name = NULL;
296 	sysmem = true;
297 
298 	/*
299 	 * The allocation is lengthened by 1 to hold a terminating NUL.  It'll
300 	 * by stripped off when devfs processes the full string.
301 	 */
302 	if (VM_MEMSEG_NAME(mseg)) {
303 		sysmem = false;
304 		name = malloc(len, M_VMMDEV, M_WAITOK);
305 		error = copystr(mseg->name, name, len, NULL);
306 		if (error)
307 			goto done;
308 	}
309 
310 	error = vm_alloc_memseg(sc->vm, mseg->segid, mseg->len, sysmem);
311 	if (error)
312 		goto done;
313 
314 	if (VM_MEMSEG_NAME(mseg)) {
315 		error = devmem_create_cdev(vm_name(sc->vm), mseg->segid, name);
316 		if (error)
317 			vm_free_memseg(sc->vm, mseg->segid);
318 		else
319 			name = NULL;	/* freed when 'cdev' is destroyed */
320 	}
321 done:
322 	free(name, M_VMMDEV);
323 	return (error);
324 }
325 
326 static int
vm_get_register_set(struct vm * vm,int vcpu,unsigned int count,int * regnum,uint64_t * regval)327 vm_get_register_set(struct vm *vm, int vcpu, unsigned int count, int *regnum,
328     uint64_t *regval)
329 {
330 	int error, i;
331 
332 	error = 0;
333 	for (i = 0; i < count; i++) {
334 		error = vm_get_register(vm, vcpu, regnum[i], &regval[i]);
335 		if (error)
336 			break;
337 	}
338 	return (error);
339 }
340 
341 static int
vm_set_register_set(struct vm * vm,int vcpu,unsigned int count,int * regnum,uint64_t * regval)342 vm_set_register_set(struct vm *vm, int vcpu, unsigned int count, int *regnum,
343     uint64_t *regval)
344 {
345 	int error, i;
346 
347 	error = 0;
348 	for (i = 0; i < count; i++) {
349 		error = vm_set_register(vm, vcpu, regnum[i], regval[i]);
350 		if (error)
351 			break;
352 	}
353 	return (error);
354 }
355 
356 static int
vmmdev_ioctl(struct cdev * cdev,u_long cmd,caddr_t data,int fflag,struct thread * td)357 vmmdev_ioctl(struct cdev *cdev, u_long cmd, caddr_t data, int fflag,
358 	     struct thread *td)
359 {
360 	int error, vcpu, state_changed, size;
361 	cpuset_t *cpuset;
362 	struct vmmdev_softc *sc;
363 	struct vm_register *vmreg;
364 	struct vm_seg_desc *vmsegdesc;
365 	struct vm_register_set *vmregset;
366 	struct vm_run *vmrun;
367 	struct vm_exception *vmexc;
368 	struct vm_lapic_irq *vmirq;
369 	struct vm_lapic_msi *vmmsi;
370 	struct vm_ioapic_irq *ioapic_irq;
371 	struct vm_isa_irq *isa_irq;
372 	struct vm_isa_irq_trigger *isa_irq_trigger;
373 	struct vm_capability *vmcap;
374 	struct vm_pptdev *pptdev;
375 	struct vm_pptdev_mmio *pptmmio;
376 	struct vm_pptdev_msi *pptmsi;
377 	struct vm_pptdev_msix *pptmsix;
378 	struct vm_nmi *vmnmi;
379 	struct vm_stats *vmstats;
380 	struct vm_stat_desc *statdesc;
381 	struct vm_x2apic *x2apic;
382 	struct vm_gpa_pte *gpapte;
383 	struct vm_suspend *vmsuspend;
384 	struct vm_gla2gpa *gg;
385 	struct vm_activate_cpu *vac;
386 	struct vm_cpuset *vm_cpuset;
387 	struct vm_intinfo *vmii;
388 	struct vm_rtc_time *rtctime;
389 	struct vm_rtc_data *rtcdata;
390 	struct vm_memmap *mm;
391 	struct vm_munmap *mu;
392 	struct vm_cpu_topology *topology;
393 	struct vm_readwrite_kernemu_device *kernemu;
394 	uint64_t *regvals;
395 	int *regnums;
396 #ifdef BHYVE_SNAPSHOT
397 	struct vm_snapshot_meta *snapshot_meta;
398 #endif
399 
400 	error = vmm_priv_check(curthread->td_ucred);
401 	if (error)
402 		return (error);
403 
404 	sc = vmmdev_lookup2(cdev);
405 	if (sc == NULL)
406 		return (ENXIO);
407 
408 	vcpu = -1;
409 	state_changed = 0;
410 
411 	/*
412 	 * Some VMM ioctls can operate only on vcpus that are not running.
413 	 */
414 	switch (cmd) {
415 	case VM_RUN:
416 	case VM_GET_REGISTER:
417 	case VM_SET_REGISTER:
418 	case VM_GET_SEGMENT_DESCRIPTOR:
419 	case VM_SET_SEGMENT_DESCRIPTOR:
420 	case VM_GET_REGISTER_SET:
421 	case VM_SET_REGISTER_SET:
422 	case VM_INJECT_EXCEPTION:
423 	case VM_GET_CAPABILITY:
424 	case VM_SET_CAPABILITY:
425 	case VM_PPTDEV_MSI:
426 	case VM_PPTDEV_MSIX:
427 	case VM_SET_X2APIC_STATE:
428 	case VM_GLA2GPA:
429 	case VM_GLA2GPA_NOFAULT:
430 	case VM_ACTIVATE_CPU:
431 	case VM_SET_INTINFO:
432 	case VM_GET_INTINFO:
433 	case VM_RESTART_INSTRUCTION:
434 		/*
435 		 * XXX fragile, handle with care
436 		 * Assumes that the first field of the ioctl data is the vcpu.
437 		 */
438 		vcpu = *(int *)data;
439 		error = vcpu_lock_one(sc, vcpu);
440 		if (error)
441 			goto done;
442 		state_changed = 1;
443 		break;
444 
445 	case VM_MAP_PPTDEV_MMIO:
446 	case VM_UNMAP_PPTDEV_MMIO:
447 	case VM_BIND_PPTDEV:
448 	case VM_UNBIND_PPTDEV:
449 #ifdef COMPAT_FREEBSD12
450 	case VM_ALLOC_MEMSEG_FBSD12:
451 #endif
452 	case VM_ALLOC_MEMSEG:
453 	case VM_MMAP_MEMSEG:
454 	case VM_MUNMAP_MEMSEG:
455 	case VM_REINIT:
456 		/*
457 		 * ioctls that operate on the entire virtual machine must
458 		 * prevent all vcpus from running.
459 		 */
460 		error = vcpu_lock_all(sc);
461 		if (error)
462 			goto done;
463 		state_changed = 2;
464 		break;
465 
466 #ifdef COMPAT_FREEBSD12
467 	case VM_GET_MEMSEG_FBSD12:
468 #endif
469 	case VM_GET_MEMSEG:
470 	case VM_MMAP_GETNEXT:
471 		/*
472 		 * Lock a vcpu to make sure that the memory map cannot be
473 		 * modified while it is being inspected.
474 		 */
475 		vcpu = vm_get_maxcpus(sc->vm) - 1;
476 		error = vcpu_lock_one(sc, vcpu);
477 		if (error)
478 			goto done;
479 		state_changed = 1;
480 		break;
481 
482 	default:
483 		break;
484 	}
485 
486 	switch(cmd) {
487 	case VM_RUN:
488 		vmrun = (struct vm_run *)data;
489 		error = vm_run(sc->vm, vmrun);
490 		break;
491 	case VM_SUSPEND:
492 		vmsuspend = (struct vm_suspend *)data;
493 		error = vm_suspend(sc->vm, vmsuspend->how);
494 		break;
495 	case VM_REINIT:
496 		error = vm_reinit(sc->vm);
497 		break;
498 	case VM_STAT_DESC: {
499 		statdesc = (struct vm_stat_desc *)data;
500 		error = vmm_stat_desc_copy(statdesc->index,
501 					statdesc->desc, sizeof(statdesc->desc));
502 		break;
503 	}
504 	case VM_STATS: {
505 		CTASSERT(MAX_VM_STATS >= MAX_VMM_STAT_ELEMS);
506 		vmstats = (struct vm_stats *)data;
507 		getmicrotime(&vmstats->tv);
508 		error = vmm_stat_copy(sc->vm, vmstats->cpuid,
509 				      &vmstats->num_entries, vmstats->statbuf);
510 		break;
511 	}
512 	case VM_PPTDEV_MSI:
513 		pptmsi = (struct vm_pptdev_msi *)data;
514 		error = ppt_setup_msi(sc->vm, pptmsi->vcpu,
515 				      pptmsi->bus, pptmsi->slot, pptmsi->func,
516 				      pptmsi->addr, pptmsi->msg,
517 				      pptmsi->numvec);
518 		break;
519 	case VM_PPTDEV_MSIX:
520 		pptmsix = (struct vm_pptdev_msix *)data;
521 		error = ppt_setup_msix(sc->vm, pptmsix->vcpu,
522 				       pptmsix->bus, pptmsix->slot,
523 				       pptmsix->func, pptmsix->idx,
524 				       pptmsix->addr, pptmsix->msg,
525 				       pptmsix->vector_control);
526 		break;
527 	case VM_PPTDEV_DISABLE_MSIX:
528 		pptdev = (struct vm_pptdev *)data;
529 		error = ppt_disable_msix(sc->vm, pptdev->bus, pptdev->slot,
530 					 pptdev->func);
531 		break;
532 	case VM_MAP_PPTDEV_MMIO:
533 		pptmmio = (struct vm_pptdev_mmio *)data;
534 		error = ppt_map_mmio(sc->vm, pptmmio->bus, pptmmio->slot,
535 				     pptmmio->func, pptmmio->gpa, pptmmio->len,
536 				     pptmmio->hpa);
537 		break;
538 	case VM_UNMAP_PPTDEV_MMIO:
539 		pptmmio = (struct vm_pptdev_mmio *)data;
540 		error = ppt_unmap_mmio(sc->vm, pptmmio->bus, pptmmio->slot,
541 				       pptmmio->func, pptmmio->gpa, pptmmio->len);
542 		break;
543 	case VM_BIND_PPTDEV:
544 		pptdev = (struct vm_pptdev *)data;
545 		error = vm_assign_pptdev(sc->vm, pptdev->bus, pptdev->slot,
546 					 pptdev->func);
547 		break;
548 	case VM_UNBIND_PPTDEV:
549 		pptdev = (struct vm_pptdev *)data;
550 		error = vm_unassign_pptdev(sc->vm, pptdev->bus, pptdev->slot,
551 					   pptdev->func);
552 		break;
553 	case VM_INJECT_EXCEPTION:
554 		vmexc = (struct vm_exception *)data;
555 		error = vm_inject_exception(sc->vm, vmexc->cpuid,
556 		    vmexc->vector, vmexc->error_code_valid, vmexc->error_code,
557 		    vmexc->restart_instruction);
558 		break;
559 	case VM_INJECT_NMI:
560 		vmnmi = (struct vm_nmi *)data;
561 		error = vm_inject_nmi(sc->vm, vmnmi->cpuid);
562 		break;
563 	case VM_LAPIC_IRQ:
564 		vmirq = (struct vm_lapic_irq *)data;
565 		error = lapic_intr_edge(sc->vm, vmirq->cpuid, vmirq->vector);
566 		break;
567 	case VM_LAPIC_LOCAL_IRQ:
568 		vmirq = (struct vm_lapic_irq *)data;
569 		error = lapic_set_local_intr(sc->vm, vmirq->cpuid,
570 		    vmirq->vector);
571 		break;
572 	case VM_LAPIC_MSI:
573 		vmmsi = (struct vm_lapic_msi *)data;
574 		error = lapic_intr_msi(sc->vm, vmmsi->addr, vmmsi->msg);
575 		break;
576 	case VM_IOAPIC_ASSERT_IRQ:
577 		ioapic_irq = (struct vm_ioapic_irq *)data;
578 		error = vioapic_assert_irq(sc->vm, ioapic_irq->irq);
579 		break;
580 	case VM_IOAPIC_DEASSERT_IRQ:
581 		ioapic_irq = (struct vm_ioapic_irq *)data;
582 		error = vioapic_deassert_irq(sc->vm, ioapic_irq->irq);
583 		break;
584 	case VM_IOAPIC_PULSE_IRQ:
585 		ioapic_irq = (struct vm_ioapic_irq *)data;
586 		error = vioapic_pulse_irq(sc->vm, ioapic_irq->irq);
587 		break;
588 	case VM_IOAPIC_PINCOUNT:
589 		*(int *)data = vioapic_pincount(sc->vm);
590 		break;
591 	case VM_SET_KERNEMU_DEV:
592 	case VM_GET_KERNEMU_DEV: {
593 		mem_region_write_t mwrite;
594 		mem_region_read_t mread;
595 		bool arg;
596 
597 		kernemu = (void *)data;
598 
599 		if (kernemu->access_width > 0)
600 			size = (1u << kernemu->access_width);
601 		else
602 			size = 1;
603 
604 		if (kernemu->gpa >= DEFAULT_APIC_BASE && kernemu->gpa < DEFAULT_APIC_BASE + PAGE_SIZE) {
605 			mread = lapic_mmio_read;
606 			mwrite = lapic_mmio_write;
607 		} else if (kernemu->gpa >= VIOAPIC_BASE && kernemu->gpa < VIOAPIC_BASE + VIOAPIC_SIZE) {
608 			mread = vioapic_mmio_read;
609 			mwrite = vioapic_mmio_write;
610 		} else if (kernemu->gpa >= VHPET_BASE && kernemu->gpa < VHPET_BASE + VHPET_SIZE) {
611 			mread = vhpet_mmio_read;
612 			mwrite = vhpet_mmio_write;
613 		} else {
614 			error = EINVAL;
615 			break;
616 		}
617 
618 		if (cmd == VM_SET_KERNEMU_DEV)
619 			error = mwrite(sc->vm, kernemu->vcpuid, kernemu->gpa,
620 			    kernemu->value, size, &arg);
621 		else
622 			error = mread(sc->vm, kernemu->vcpuid, kernemu->gpa,
623 			    &kernemu->value, size, &arg);
624 		break;
625 		}
626 	case VM_ISA_ASSERT_IRQ:
627 		isa_irq = (struct vm_isa_irq *)data;
628 		error = vatpic_assert_irq(sc->vm, isa_irq->atpic_irq);
629 		if (error == 0 && isa_irq->ioapic_irq != -1)
630 			error = vioapic_assert_irq(sc->vm,
631 			    isa_irq->ioapic_irq);
632 		break;
633 	case VM_ISA_DEASSERT_IRQ:
634 		isa_irq = (struct vm_isa_irq *)data;
635 		error = vatpic_deassert_irq(sc->vm, isa_irq->atpic_irq);
636 		if (error == 0 && isa_irq->ioapic_irq != -1)
637 			error = vioapic_deassert_irq(sc->vm,
638 			    isa_irq->ioapic_irq);
639 		break;
640 	case VM_ISA_PULSE_IRQ:
641 		isa_irq = (struct vm_isa_irq *)data;
642 		error = vatpic_pulse_irq(sc->vm, isa_irq->atpic_irq);
643 		if (error == 0 && isa_irq->ioapic_irq != -1)
644 			error = vioapic_pulse_irq(sc->vm, isa_irq->ioapic_irq);
645 		break;
646 	case VM_ISA_SET_IRQ_TRIGGER:
647 		isa_irq_trigger = (struct vm_isa_irq_trigger *)data;
648 		error = vatpic_set_irq_trigger(sc->vm,
649 		    isa_irq_trigger->atpic_irq, isa_irq_trigger->trigger);
650 		break;
651 	case VM_MMAP_GETNEXT:
652 		mm = (struct vm_memmap *)data;
653 		error = vm_mmap_getnext(sc->vm, &mm->gpa, &mm->segid,
654 		    &mm->segoff, &mm->len, &mm->prot, &mm->flags);
655 		break;
656 	case VM_MMAP_MEMSEG:
657 		mm = (struct vm_memmap *)data;
658 		error = vm_mmap_memseg(sc->vm, mm->gpa, mm->segid, mm->segoff,
659 		    mm->len, mm->prot, mm->flags);
660 		break;
661 	case VM_MUNMAP_MEMSEG:
662 		mu = (struct vm_munmap *)data;
663 		error = vm_munmap_memseg(sc->vm, mu->gpa, mu->len);
664 		break;
665 #ifdef COMPAT_FREEBSD12
666 	case VM_ALLOC_MEMSEG_FBSD12:
667 		error = alloc_memseg(sc, (struct vm_memseg *)data,
668 		    sizeof(((struct vm_memseg_fbsd12 *)0)->name));
669 		break;
670 #endif
671 	case VM_ALLOC_MEMSEG:
672 		error = alloc_memseg(sc, (struct vm_memseg *)data,
673 		    sizeof(((struct vm_memseg *)0)->name));
674 		break;
675 #ifdef COMPAT_FREEBSD12
676 	case VM_GET_MEMSEG_FBSD12:
677 		error = get_memseg(sc, (struct vm_memseg *)data,
678 		    sizeof(((struct vm_memseg_fbsd12 *)0)->name));
679 		break;
680 #endif
681 	case VM_GET_MEMSEG:
682 		error = get_memseg(sc, (struct vm_memseg *)data,
683 		    sizeof(((struct vm_memseg *)0)->name));
684 		break;
685 	case VM_GET_REGISTER:
686 		vmreg = (struct vm_register *)data;
687 		error = vm_get_register(sc->vm, vmreg->cpuid, vmreg->regnum,
688 					&vmreg->regval);
689 		break;
690 	case VM_SET_REGISTER:
691 		vmreg = (struct vm_register *)data;
692 		error = vm_set_register(sc->vm, vmreg->cpuid, vmreg->regnum,
693 					vmreg->regval);
694 		break;
695 	case VM_SET_SEGMENT_DESCRIPTOR:
696 		vmsegdesc = (struct vm_seg_desc *)data;
697 		error = vm_set_seg_desc(sc->vm, vmsegdesc->cpuid,
698 					vmsegdesc->regnum,
699 					&vmsegdesc->desc);
700 		break;
701 	case VM_GET_SEGMENT_DESCRIPTOR:
702 		vmsegdesc = (struct vm_seg_desc *)data;
703 		error = vm_get_seg_desc(sc->vm, vmsegdesc->cpuid,
704 					vmsegdesc->regnum,
705 					&vmsegdesc->desc);
706 		break;
707 	case VM_GET_REGISTER_SET:
708 		vmregset = (struct vm_register_set *)data;
709 		if (vmregset->count > VM_REG_LAST) {
710 			error = EINVAL;
711 			break;
712 		}
713 		regvals = malloc(sizeof(regvals[0]) * vmregset->count, M_VMMDEV,
714 		    M_WAITOK);
715 		regnums = malloc(sizeof(regnums[0]) * vmregset->count, M_VMMDEV,
716 		    M_WAITOK);
717 		error = copyin(vmregset->regnums, regnums, sizeof(regnums[0]) *
718 		    vmregset->count);
719 		if (error == 0)
720 			error = vm_get_register_set(sc->vm, vmregset->cpuid,
721 			    vmregset->count, regnums, regvals);
722 		if (error == 0)
723 			error = copyout(regvals, vmregset->regvals,
724 			    sizeof(regvals[0]) * vmregset->count);
725 		free(regvals, M_VMMDEV);
726 		free(regnums, M_VMMDEV);
727 		break;
728 	case VM_SET_REGISTER_SET:
729 		vmregset = (struct vm_register_set *)data;
730 		if (vmregset->count > VM_REG_LAST) {
731 			error = EINVAL;
732 			break;
733 		}
734 		regvals = malloc(sizeof(regvals[0]) * vmregset->count, M_VMMDEV,
735 		    M_WAITOK);
736 		regnums = malloc(sizeof(regnums[0]) * vmregset->count, M_VMMDEV,
737 		    M_WAITOK);
738 		error = copyin(vmregset->regnums, regnums, sizeof(regnums[0]) *
739 		    vmregset->count);
740 		if (error == 0)
741 			error = copyin(vmregset->regvals, regvals,
742 			    sizeof(regvals[0]) * vmregset->count);
743 		if (error == 0)
744 			error = vm_set_register_set(sc->vm, vmregset->cpuid,
745 			    vmregset->count, regnums, regvals);
746 		free(regvals, M_VMMDEV);
747 		free(regnums, M_VMMDEV);
748 		break;
749 	case VM_GET_CAPABILITY:
750 		vmcap = (struct vm_capability *)data;
751 		error = vm_get_capability(sc->vm, vmcap->cpuid,
752 					  vmcap->captype,
753 					  &vmcap->capval);
754 		break;
755 	case VM_SET_CAPABILITY:
756 		vmcap = (struct vm_capability *)data;
757 		error = vm_set_capability(sc->vm, vmcap->cpuid,
758 					  vmcap->captype,
759 					  vmcap->capval);
760 		break;
761 	case VM_SET_X2APIC_STATE:
762 		x2apic = (struct vm_x2apic *)data;
763 		error = vm_set_x2apic_state(sc->vm,
764 					    x2apic->cpuid, x2apic->state);
765 		break;
766 	case VM_GET_X2APIC_STATE:
767 		x2apic = (struct vm_x2apic *)data;
768 		error = vm_get_x2apic_state(sc->vm,
769 					    x2apic->cpuid, &x2apic->state);
770 		break;
771 	case VM_GET_GPA_PMAP:
772 		gpapte = (struct vm_gpa_pte *)data;
773 		pmap_get_mapping(vmspace_pmap(vm_get_vmspace(sc->vm)),
774 				 gpapte->gpa, gpapte->pte, &gpapte->ptenum);
775 		error = 0;
776 		break;
777 	case VM_GET_HPET_CAPABILITIES:
778 		error = vhpet_getcap((struct vm_hpet_cap *)data);
779 		break;
780 	case VM_GLA2GPA: {
781 		CTASSERT(PROT_READ == VM_PROT_READ);
782 		CTASSERT(PROT_WRITE == VM_PROT_WRITE);
783 		CTASSERT(PROT_EXEC == VM_PROT_EXECUTE);
784 		gg = (struct vm_gla2gpa *)data;
785 		error = vm_gla2gpa(sc->vm, gg->vcpuid, &gg->paging, gg->gla,
786 		    gg->prot, &gg->gpa, &gg->fault);
787 		KASSERT(error == 0 || error == EFAULT,
788 		    ("%s: vm_gla2gpa unknown error %d", __func__, error));
789 		break;
790 	}
791 	case VM_GLA2GPA_NOFAULT:
792 		gg = (struct vm_gla2gpa *)data;
793 		error = vm_gla2gpa_nofault(sc->vm, gg->vcpuid, &gg->paging,
794 		    gg->gla, gg->prot, &gg->gpa, &gg->fault);
795 		KASSERT(error == 0 || error == EFAULT,
796 		    ("%s: vm_gla2gpa unknown error %d", __func__, error));
797 		break;
798 	case VM_ACTIVATE_CPU:
799 		vac = (struct vm_activate_cpu *)data;
800 		error = vm_activate_cpu(sc->vm, vac->vcpuid);
801 		break;
802 	case VM_GET_CPUS:
803 		error = 0;
804 		vm_cpuset = (struct vm_cpuset *)data;
805 		size = vm_cpuset->cpusetsize;
806 		if (size < sizeof(cpuset_t) || size > CPU_MAXSIZE / NBBY) {
807 			error = ERANGE;
808 			break;
809 		}
810 		cpuset = malloc(size, M_TEMP, M_WAITOK | M_ZERO);
811 		if (vm_cpuset->which == VM_ACTIVE_CPUS)
812 			*cpuset = vm_active_cpus(sc->vm);
813 		else if (vm_cpuset->which == VM_SUSPENDED_CPUS)
814 			*cpuset = vm_suspended_cpus(sc->vm);
815 		else if (vm_cpuset->which == VM_DEBUG_CPUS)
816 			*cpuset = vm_debug_cpus(sc->vm);
817 		else
818 			error = EINVAL;
819 		if (error == 0)
820 			error = copyout(cpuset, vm_cpuset->cpus, size);
821 		free(cpuset, M_TEMP);
822 		break;
823 	case VM_SUSPEND_CPU:
824 		vac = (struct vm_activate_cpu *)data;
825 		error = vm_suspend_cpu(sc->vm, vac->vcpuid);
826 		break;
827 	case VM_RESUME_CPU:
828 		vac = (struct vm_activate_cpu *)data;
829 		error = vm_resume_cpu(sc->vm, vac->vcpuid);
830 		break;
831 	case VM_SET_INTINFO:
832 		vmii = (struct vm_intinfo *)data;
833 		error = vm_exit_intinfo(sc->vm, vmii->vcpuid, vmii->info1);
834 		break;
835 	case VM_GET_INTINFO:
836 		vmii = (struct vm_intinfo *)data;
837 		error = vm_get_intinfo(sc->vm, vmii->vcpuid, &vmii->info1,
838 		    &vmii->info2);
839 		break;
840 	case VM_RTC_WRITE:
841 		rtcdata = (struct vm_rtc_data *)data;
842 		error = vrtc_nvram_write(sc->vm, rtcdata->offset,
843 		    rtcdata->value);
844 		break;
845 	case VM_RTC_READ:
846 		rtcdata = (struct vm_rtc_data *)data;
847 		error = vrtc_nvram_read(sc->vm, rtcdata->offset,
848 		    &rtcdata->value);
849 		break;
850 	case VM_RTC_SETTIME:
851 		rtctime = (struct vm_rtc_time *)data;
852 		error = vrtc_set_time(sc->vm, rtctime->secs);
853 		break;
854 	case VM_RTC_GETTIME:
855 		error = 0;
856 		rtctime = (struct vm_rtc_time *)data;
857 		rtctime->secs = vrtc_get_time(sc->vm);
858 		break;
859 	case VM_RESTART_INSTRUCTION:
860 		error = vm_restart_instruction(sc->vm, vcpu);
861 		break;
862 	case VM_SET_TOPOLOGY:
863 		topology = (struct vm_cpu_topology *)data;
864 		error = vm_set_topology(sc->vm, topology->sockets,
865 		    topology->cores, topology->threads, topology->maxcpus);
866 		break;
867 	case VM_GET_TOPOLOGY:
868 		topology = (struct vm_cpu_topology *)data;
869 		vm_get_topology(sc->vm, &topology->sockets, &topology->cores,
870 		    &topology->threads, &topology->maxcpus);
871 		error = 0;
872 		break;
873 #ifdef BHYVE_SNAPSHOT
874 	case VM_SNAPSHOT_REQ:
875 		snapshot_meta = (struct vm_snapshot_meta *)data;
876 		error = vm_snapshot_req(sc->vm, snapshot_meta);
877 		break;
878 	case VM_RESTORE_TIME:
879 		error = vm_restore_time(sc->vm);
880 		break;
881 #endif
882 	default:
883 		error = ENOTTY;
884 		break;
885 	}
886 
887 	if (state_changed == 1)
888 		vcpu_unlock_one(sc, vcpu);
889 	else if (state_changed == 2)
890 		vcpu_unlock_all(sc);
891 
892 done:
893 	/*
894 	 * Make sure that no handler returns a kernel-internal
895 	 * error value to userspace.
896 	 */
897 	KASSERT(error == ERESTART || error >= 0,
898 	    ("vmmdev_ioctl: invalid error return %d", error));
899 	return (error);
900 }
901 
902 static int
vmmdev_mmap_single(struct cdev * cdev,vm_ooffset_t * offset,vm_size_t mapsize,struct vm_object ** objp,int nprot)903 vmmdev_mmap_single(struct cdev *cdev, vm_ooffset_t *offset, vm_size_t mapsize,
904     struct vm_object **objp, int nprot)
905 {
906 	struct vmmdev_softc *sc;
907 	vm_paddr_t gpa;
908 	size_t len;
909 	vm_ooffset_t segoff, first, last;
910 	int error, found, segid;
911 	uint16_t lastcpu;
912 	bool sysmem;
913 
914 	error = vmm_priv_check(curthread->td_ucred);
915 	if (error)
916 		return (error);
917 
918 	first = *offset;
919 	last = first + mapsize;
920 	if ((nprot & PROT_EXEC) || first < 0 || first >= last)
921 		return (EINVAL);
922 
923 	sc = vmmdev_lookup2(cdev);
924 	if (sc == NULL) {
925 		/* virtual machine is in the process of being created */
926 		return (EINVAL);
927 	}
928 
929 	/*
930 	 * Get a read lock on the guest memory map by freezing any vcpu.
931 	 */
932 	lastcpu = vm_get_maxcpus(sc->vm) - 1;
933 	error = vcpu_lock_one(sc, lastcpu);
934 	if (error)
935 		return (error);
936 
937 	gpa = 0;
938 	found = 0;
939 	while (!found) {
940 		error = vm_mmap_getnext(sc->vm, &gpa, &segid, &segoff, &len,
941 		    NULL, NULL);
942 		if (error)
943 			break;
944 
945 		if (first >= gpa && last <= gpa + len)
946 			found = 1;
947 		else
948 			gpa += len;
949 	}
950 
951 	if (found) {
952 		error = vm_get_memseg(sc->vm, segid, &len, &sysmem, objp);
953 		KASSERT(error == 0 && *objp != NULL,
954 		    ("%s: invalid memory segment %d", __func__, segid));
955 		if (sysmem) {
956 			vm_object_reference(*objp);
957 			*offset = segoff + (first - gpa);
958 		} else {
959 			error = EINVAL;
960 		}
961 	}
962 	vcpu_unlock_one(sc, lastcpu);
963 	return (error);
964 }
965 
966 static void
vmmdev_destroy(void * arg)967 vmmdev_destroy(void *arg)
968 {
969 	struct vmmdev_softc *sc = arg;
970 	struct devmem_softc *dsc;
971 	int error;
972 
973 	error = vcpu_lock_all(sc);
974 	KASSERT(error == 0, ("%s: error %d freezing vcpus", __func__, error));
975 
976 	while ((dsc = SLIST_FIRST(&sc->devmem)) != NULL) {
977 		KASSERT(dsc->cdev == NULL, ("%s: devmem not free", __func__));
978 		SLIST_REMOVE_HEAD(&sc->devmem, link);
979 		free(dsc->name, M_VMMDEV);
980 		free(dsc, M_VMMDEV);
981 	}
982 
983 	if (sc->cdev != NULL)
984 		destroy_dev(sc->cdev);
985 
986 	if (sc->vm != NULL)
987 		vm_destroy(sc->vm);
988 
989 	if (sc->ucred != NULL)
990 		crfree(sc->ucred);
991 
992 	if ((sc->flags & VSC_LINKED) != 0) {
993 		mtx_lock(&vmmdev_mtx);
994 		SLIST_REMOVE(&head, sc, vmmdev_softc, link);
995 		mtx_unlock(&vmmdev_mtx);
996 	}
997 
998 	free(sc, M_VMMDEV);
999 }
1000 
1001 static int
sysctl_vmm_destroy(SYSCTL_HANDLER_ARGS)1002 sysctl_vmm_destroy(SYSCTL_HANDLER_ARGS)
1003 {
1004 	struct devmem_softc *dsc;
1005 	struct vmmdev_softc *sc;
1006 	struct cdev *cdev;
1007 	char *buf;
1008 	int error, buflen;
1009 
1010 	error = vmm_priv_check(req->td->td_ucred);
1011 	if (error)
1012 		return (error);
1013 
1014 	buflen = VM_MAX_NAMELEN + 1;
1015 	buf = malloc(buflen, M_VMMDEV, M_WAITOK | M_ZERO);
1016 	strlcpy(buf, "beavis", buflen);
1017 	error = sysctl_handle_string(oidp, buf, buflen, req);
1018 	if (error != 0 || req->newptr == NULL)
1019 		goto out;
1020 
1021 	mtx_lock(&vmmdev_mtx);
1022 	sc = vmmdev_lookup(buf);
1023 	if (sc == NULL || sc->cdev == NULL) {
1024 		mtx_unlock(&vmmdev_mtx);
1025 		error = EINVAL;
1026 		goto out;
1027 	}
1028 
1029 	/*
1030 	 * The 'cdev' will be destroyed asynchronously when 'si_threadcount'
1031 	 * goes down to 0 so we should not do it again in the callback.
1032 	 *
1033 	 * Setting 'sc->cdev' to NULL is also used to indicate that the VM
1034 	 * is scheduled for destruction.
1035 	 */
1036 	cdev = sc->cdev;
1037 	sc->cdev = NULL;
1038 	mtx_unlock(&vmmdev_mtx);
1039 
1040 	/*
1041 	 * Schedule all cdevs to be destroyed:
1042 	 *
1043 	 * - any new operations on the 'cdev' will return an error (ENXIO).
1044 	 *
1045 	 * - when the 'si_threadcount' dwindles down to zero the 'cdev' will
1046 	 *   be destroyed and the callback will be invoked in a taskqueue
1047 	 *   context.
1048 	 *
1049 	 * - the 'devmem' cdevs are destroyed before the virtual machine 'cdev'
1050 	 */
1051 	SLIST_FOREACH(dsc, &sc->devmem, link) {
1052 		KASSERT(dsc->cdev != NULL, ("devmem cdev already destroyed"));
1053 		destroy_dev_sched_cb(dsc->cdev, devmem_destroy, dsc);
1054 	}
1055 	destroy_dev_sched_cb(cdev, vmmdev_destroy, sc);
1056 	error = 0;
1057 
1058 out:
1059 	free(buf, M_VMMDEV);
1060 	return (error);
1061 }
1062 SYSCTL_PROC(_hw_vmm, OID_AUTO, destroy,
1063     CTLTYPE_STRING | CTLFLAG_RW | CTLFLAG_PRISON | CTLFLAG_MPSAFE,
1064     NULL, 0, sysctl_vmm_destroy, "A",
1065     NULL);
1066 
1067 static struct cdevsw vmmdevsw = {
1068 	.d_name		= "vmmdev",
1069 	.d_version	= D_VERSION,
1070 	.d_ioctl	= vmmdev_ioctl,
1071 	.d_mmap_single	= vmmdev_mmap_single,
1072 	.d_read		= vmmdev_rw,
1073 	.d_write	= vmmdev_rw,
1074 };
1075 
1076 static int
sysctl_vmm_create(SYSCTL_HANDLER_ARGS)1077 sysctl_vmm_create(SYSCTL_HANDLER_ARGS)
1078 {
1079 	struct vm *vm;
1080 	struct cdev *cdev;
1081 	struct vmmdev_softc *sc, *sc2;
1082 	char *buf;
1083 	int error, buflen;
1084 
1085 	error = vmm_priv_check(req->td->td_ucred);
1086 	if (error)
1087 		return (error);
1088 
1089 	buflen = VM_MAX_NAMELEN + 1;
1090 	buf = malloc(buflen, M_VMMDEV, M_WAITOK | M_ZERO);
1091 	strlcpy(buf, "beavis", buflen);
1092 	error = sysctl_handle_string(oidp, buf, buflen, req);
1093 	if (error != 0 || req->newptr == NULL)
1094 		goto out;
1095 
1096 	mtx_lock(&vmmdev_mtx);
1097 	sc = vmmdev_lookup(buf);
1098 	mtx_unlock(&vmmdev_mtx);
1099 	if (sc != NULL) {
1100 		error = EEXIST;
1101 		goto out;
1102 	}
1103 
1104 	error = vm_create(buf, &vm);
1105 	if (error != 0)
1106 		goto out;
1107 
1108 	sc = malloc(sizeof(struct vmmdev_softc), M_VMMDEV, M_WAITOK | M_ZERO);
1109 	sc->ucred = crhold(curthread->td_ucred);
1110 	sc->vm = vm;
1111 	SLIST_INIT(&sc->devmem);
1112 
1113 	/*
1114 	 * Lookup the name again just in case somebody sneaked in when we
1115 	 * dropped the lock.
1116 	 */
1117 	mtx_lock(&vmmdev_mtx);
1118 	sc2 = vmmdev_lookup(buf);
1119 	if (sc2 == NULL) {
1120 		SLIST_INSERT_HEAD(&head, sc, link);
1121 		sc->flags |= VSC_LINKED;
1122 	}
1123 	mtx_unlock(&vmmdev_mtx);
1124 
1125 	if (sc2 != NULL) {
1126 		vmmdev_destroy(sc);
1127 		error = EEXIST;
1128 		goto out;
1129 	}
1130 
1131 	error = make_dev_p(MAKEDEV_CHECKNAME, &cdev, &vmmdevsw, sc->ucred,
1132 	    UID_ROOT, GID_WHEEL, 0600, "vmm/%s", buf);
1133 	if (error != 0) {
1134 		vmmdev_destroy(sc);
1135 		goto out;
1136 	}
1137 
1138 	mtx_lock(&vmmdev_mtx);
1139 	sc->cdev = cdev;
1140 	sc->cdev->si_drv1 = sc;
1141 	mtx_unlock(&vmmdev_mtx);
1142 
1143 out:
1144 	free(buf, M_VMMDEV);
1145 	return (error);
1146 }
1147 SYSCTL_PROC(_hw_vmm, OID_AUTO, create,
1148     CTLTYPE_STRING | CTLFLAG_RW | CTLFLAG_PRISON | CTLFLAG_MPSAFE,
1149     NULL, 0, sysctl_vmm_create, "A",
1150     NULL);
1151 
1152 void
vmmdev_init(void)1153 vmmdev_init(void)
1154 {
1155 	mtx_init(&vmmdev_mtx, "vmm device mutex", NULL, MTX_DEF);
1156 	pr_allow_flag = prison_add_allow(NULL, "vmm", NULL,
1157 	    "Allow use of vmm in a jail.");
1158 }
1159 
1160 int
vmmdev_cleanup(void)1161 vmmdev_cleanup(void)
1162 {
1163 	int error;
1164 
1165 	if (SLIST_EMPTY(&head))
1166 		error = 0;
1167 	else
1168 		error = EBUSY;
1169 
1170 	return (error);
1171 }
1172 
1173 static int
devmem_mmap_single(struct cdev * cdev,vm_ooffset_t * offset,vm_size_t len,struct vm_object ** objp,int nprot)1174 devmem_mmap_single(struct cdev *cdev, vm_ooffset_t *offset, vm_size_t len,
1175     struct vm_object **objp, int nprot)
1176 {
1177 	struct devmem_softc *dsc;
1178 	vm_ooffset_t first, last;
1179 	size_t seglen;
1180 	int error;
1181 	uint16_t lastcpu;
1182 	bool sysmem;
1183 
1184 	dsc = cdev->si_drv1;
1185 	if (dsc == NULL) {
1186 		/* 'cdev' has been created but is not ready for use */
1187 		return (ENXIO);
1188 	}
1189 
1190 	first = *offset;
1191 	last = *offset + len;
1192 	if ((nprot & PROT_EXEC) || first < 0 || first >= last)
1193 		return (EINVAL);
1194 
1195 	lastcpu = vm_get_maxcpus(dsc->sc->vm) - 1;
1196 	error = vcpu_lock_one(dsc->sc, lastcpu);
1197 	if (error)
1198 		return (error);
1199 
1200 	error = vm_get_memseg(dsc->sc->vm, dsc->segid, &seglen, &sysmem, objp);
1201 	KASSERT(error == 0 && !sysmem && *objp != NULL,
1202 	    ("%s: invalid devmem segment %d", __func__, dsc->segid));
1203 
1204 	vcpu_unlock_one(dsc->sc, lastcpu);
1205 
1206 	if (seglen >= last) {
1207 		vm_object_reference(*objp);
1208 		return (0);
1209 	} else {
1210 		return (EINVAL);
1211 	}
1212 }
1213 
1214 static struct cdevsw devmemsw = {
1215 	.d_name		= "devmem",
1216 	.d_version	= D_VERSION,
1217 	.d_mmap_single	= devmem_mmap_single,
1218 };
1219 
1220 static int
devmem_create_cdev(const char * vmname,int segid,char * devname)1221 devmem_create_cdev(const char *vmname, int segid, char *devname)
1222 {
1223 	struct devmem_softc *dsc;
1224 	struct vmmdev_softc *sc;
1225 	struct cdev *cdev;
1226 	int error;
1227 
1228 	error = make_dev_p(MAKEDEV_CHECKNAME, &cdev, &devmemsw, NULL,
1229 	    UID_ROOT, GID_WHEEL, 0600, "vmm.io/%s.%s", vmname, devname);
1230 	if (error)
1231 		return (error);
1232 
1233 	dsc = malloc(sizeof(struct devmem_softc), M_VMMDEV, M_WAITOK | M_ZERO);
1234 
1235 	mtx_lock(&vmmdev_mtx);
1236 	sc = vmmdev_lookup(vmname);
1237 	KASSERT(sc != NULL, ("%s: vm %s softc not found", __func__, vmname));
1238 	if (sc->cdev == NULL) {
1239 		/* virtual machine is being created or destroyed */
1240 		mtx_unlock(&vmmdev_mtx);
1241 		free(dsc, M_VMMDEV);
1242 		destroy_dev_sched_cb(cdev, NULL, 0);
1243 		return (ENODEV);
1244 	}
1245 
1246 	dsc->segid = segid;
1247 	dsc->name = devname;
1248 	dsc->cdev = cdev;
1249 	dsc->sc = sc;
1250 	SLIST_INSERT_HEAD(&sc->devmem, dsc, link);
1251 	mtx_unlock(&vmmdev_mtx);
1252 
1253 	/* The 'cdev' is ready for use after 'si_drv1' is initialized */
1254 	cdev->si_drv1 = dsc;
1255 	return (0);
1256 }
1257 
1258 static void
devmem_destroy(void * arg)1259 devmem_destroy(void *arg)
1260 {
1261 	struct devmem_softc *dsc = arg;
1262 
1263 	KASSERT(dsc->cdev, ("%s: devmem cdev already destroyed", __func__));
1264 	dsc->cdev = NULL;
1265 	dsc->sc = NULL;
1266 }
1267