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rump.c revision 1.151 
      1 /*	$NetBSD: rump.c,v 1.151 2010/01/15 20:39:46 pooka Exp $	*/
      2 
      3 /*
      4  * Copyright (c) 2007 Antti Kantee.  All Rights Reserved.
      5  *
      6  * Development of this software was supported by Google Summer of Code.
      7  *
      8  * Redistribution and use in source and binary forms, with or without
      9  * modification, are permitted provided that the following conditions
     10  * are met:
     11  * 1. Redistributions of source code must retain the above copyright
     12  *    notice, this list of conditions and the following disclaimer.
     13  * 2. Redistributions in binary form must reproduce the above copyright
     14  *    notice, this list of conditions and the following disclaimer in the
     15  *    documentation and/or other materials provided with the distribution.
     16  *
     17  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS
     18  * OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
     19  * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
     20  * DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
     21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
     22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
     23  * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
     25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
     26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     27  * SUCH DAMAGE.
     28  */
     29 
     30 #include <sys/cdefs.h>
     31 __KERNEL_RCSID(0, "$NetBSD: rump.c,v 1.151 2010/01/15 20:39:46 pooka Exp $");
     32 
     33 #include <sys/param.h>
     34 #include <sys/atomic.h>
     35 #include <sys/buf.h>
     36 #include <sys/callout.h>
     37 #include <sys/conf.h>
     38 #include <sys/cpu.h>
     39 #include <sys/device.h>
     40 #include <sys/evcnt.h>
     41 #include <sys/event.h>
     42 #include <sys/exec_elf.h>
     43 #include <sys/filedesc.h>
     44 #include <sys/iostat.h>
     45 #include <sys/kauth.h>
     46 #include <sys/kernel.h>
     47 #include <sys/kmem.h>
     48 #include <sys/kprintf.h>
     49 #include <sys/ksyms.h>
     50 #include <sys/msgbuf.h>
     51 #include <sys/module.h>
     52 #include <sys/once.h>
     53 #include <sys/percpu.h>
     54 #include <sys/pipe.h>
     55 #include <sys/queue.h>
     56 #include <sys/reboot.h>
     57 #include <sys/resourcevar.h>
     58 #include <sys/select.h>
     59 #include <sys/sysctl.h>
     60 #include <sys/syscall.h>
     61 #include <sys/tty.h>
     62 #include <sys/uidinfo.h>
     63 #include <sys/vmem.h>
     64 #include <sys/xcall.h>
     65 
     66 #include <rump/rumpuser.h>
     67 
     68 #include <secmodel/suser/suser.h>
     69 
     70 #include <prop/proplib.h>
     71 
     72 #include <uvm/uvm_readahead.h>
     73 
     74 #include "rump_private.h"
     75 #include "rump_net_private.h"
     76 #include "rump_vfs_private.h"
     77 #include "rump_dev_private.h"
     78 
     79 struct proc proc0;
     80 struct session rump_session = {
     81 	.s_count = 1,
     82 	.s_flags = 0,
     83 	.s_leader = &proc0,
     84 	.s_login = "rumphobo",
     85 	.s_sid = 0,
     86 };
     87 struct pgrp rump_pgrp = {
     88 	.pg_members = LIST_HEAD_INITIALIZER(pg_members),
     89 	.pg_session = &rump_session,
     90 	.pg_jobc = 1,
     91 };
     92 struct pstats rump_stats;
     93 struct plimit rump_limits;
     94 struct filedesc rump_filedesc0;
     95 struct proclist allproc;
     96 char machine[] = "rump";
     97 static kauth_cred_t rump_susercred;
     98 
     99 /* pretend the master rump proc is init */
    100 struct proc *initproc = &proc0;
    101 
    102 struct rumpuser_mtx *rump_giantlock;
    103 
    104 sigset_t sigcantmask;
    105 
    106 struct device rump_rootdev = {
    107 	.dv_class = DV_VIRTUAL
    108 };
    109 
    110 #ifdef RUMP_WITHOUT_THREADS
    111 int rump_threads = 0;
    112 #else
    113 int rump_threads = 1;
    114 #endif
    115 
    116 static void
    117 rump_aiodone_worker(struct work *wk, void *dummy)
    118 {
    119 	struct buf *bp = (struct buf *)wk;
    120 
    121 	KASSERT(&bp->b_work == wk);
    122 	bp->b_iodone(bp);
    123 }
    124 
    125 static int rump_inited;
    126 static struct emul emul_rump = {
    127 	.e_vm_default_addr = uvm_default_mapaddr,
    128 };
    129 
    130 int rump__unavailable(void);
    131 int rump__unavailable() {return EOPNOTSUPP;}
    132 __weak_alias(rump_net_init,rump__unavailable);
    133 __weak_alias(rump_vfs_init,rump__unavailable);
    134 __weak_alias(rump_dev_init,rump__unavailable);
    135 
    136 __weak_alias(rump_vfs_fini,rump__unavailable);
    137 
    138 __weak_alias(biodone,rump__unavailable);
    139 __weak_alias(sopoll,rump__unavailable);
    140 
    141 void rump__unavailable_vfs_panic(void);
    142 void rump__unavailable_vfs_panic() {panic("vfs component not available");}
    143 __weak_alias(usermount_common_policy,rump__unavailable_vfs_panic);
    144 
    145 rump_proc_vfs_init_fn rump_proc_vfs_init;
    146 rump_proc_vfs_release_fn rump_proc_vfs_release;
    147 
    148 static void __noinline
    149 messthestack(void)
    150 {
    151 	volatile uint32_t mess[64];
    152 	uint64_t d1, d2;
    153 	int i, error;
    154 
    155 	for (i = 0; i < 64; i++) {
    156 		rumpuser_gettime(&d1, &d2, &error);
    157 		mess[i] = d2;
    158 	}
    159 }
    160 
    161 int
    162 rump__init(int rump_version)
    163 {
    164 	char buf[256];
    165 	struct proc *p;
    166 	struct lwp *l;
    167 	int i;
    168 	int error;
    169 
    170 	/* not reentrant */
    171 	if (rump_inited)
    172 		return 0;
    173 	else if (rump_inited == -1)
    174 		panic("rump_init: host process restart required");
    175 	else
    176 		rump_inited = 1;
    177 
    178 	if (rumpuser_getenv("RUMP_VERBOSE", buf, sizeof(buf), &error) == 0) {
    179 		if (*buf != '0')
    180 			boothowto = AB_VERBOSE;
    181 	}
    182 
    183 	/* Print some silly banners for spammy bootstrap. */
    184 	if (boothowto & AB_VERBOSE) {
    185 		printf("%s%s", copyright, version);
    186 	}
    187 
    188 	/*
    189 	 * Seed arc4random() with a "reasonable" amount of randomness.
    190 	 * Yes, this is a quick kludge which depends on the arc4random
    191 	 * implementation.
    192 	 */
    193 	messthestack();
    194 	arc4random();
    195 
    196 	if (rump_version != RUMP_VERSION) {
    197 		printf("rump version mismatch, %d vs. %d\n",
    198 		    rump_version, RUMP_VERSION);
    199 		return EPROGMISMATCH;
    200 	}
    201 
    202 	if (rumpuser_getenv("RUMP_THREADS", buf, sizeof(buf), &error) == 0) {
    203 		rump_threads = *buf != '0';
    204 	}
    205 	rumpuser_thrinit(rump_user_schedule, rump_user_unschedule,
    206 	    rump_threads);
    207 	rump_intr_init();
    208 
    209 	/* init minimal lwp/cpu context */
    210 	l = &lwp0;
    211 	l->l_lid = 1;
    212 	l->l_cpu = rump_cpu;
    213 	rumpuser_set_curlwp(l);
    214 
    215 	mutex_init(&tty_lock, MUTEX_DEFAULT, IPL_NONE);
    216 	rumpuser_mutex_recursive_init(&rump_giantlock);
    217 	ksyms_init();
    218 	rumpvm_init();
    219 	evcnt_init();
    220 
    221 	once_init();
    222 	prop_kern_init();
    223 
    224 	pool_subsystem_init();
    225 	kmem_init();
    226 
    227 	uvm_ra_init();
    228 
    229 	mutex_obj_init();
    230 	callout_startup();
    231 
    232 	kprintf_init();
    233 	loginit();
    234 
    235 	kauth_init();
    236 	rump_susercred = rump_cred_create(0, 0, 0, NULL);
    237 
    238 	/* init proc0 and rest of lwp0 now that we can allocate memory */
    239 	p = &proc0;
    240 	p->p_stats = &rump_stats;
    241 	p->p_limit = &rump_limits;
    242 	p->p_pgrp = &rump_pgrp;
    243 	p->p_pid = 0;
    244 	p->p_fd = &rump_filedesc0;
    245 	p->p_vmspace = &rump_vmspace;
    246 	p->p_emul = &emul_rump;
    247 	p->p_lock = mutex_obj_alloc(MUTEX_DEFAULT, IPL_NONE);
    248 	l->l_cred = rump_cred_suserget();
    249 	l->l_proc = p;
    250 	LIST_INIT(&allproc);
    251 	LIST_INSERT_HEAD(&allproc, &proc0, p_list);
    252 	proc_lock = mutex_obj_alloc(MUTEX_DEFAULT, IPL_NONE);
    253 
    254 	rump_limits.pl_rlimit[RLIMIT_FSIZE].rlim_cur = RLIM_INFINITY;
    255 	rump_limits.pl_rlimit[RLIMIT_NOFILE].rlim_cur = RLIM_INFINITY;
    256 	rump_limits.pl_rlimit[RLIMIT_SBSIZE].rlim_cur = RLIM_INFINITY;
    257 
    258 	rump_scheduler_init();
    259 	/* revert temporary context and schedule a real context */
    260 	l->l_cpu = NULL;
    261 	rumpuser_set_curlwp(NULL);
    262 	rump_schedule();
    263 
    264 	percpu_init();
    265 
    266 	/* we are mostly go.  do per-cpu subsystem init */
    267 	for (i = 0; i < ncpu; i++) {
    268 		struct cpu_info *ci = cpu_lookup(i);
    269 
    270 		callout_init_cpu(ci);
    271 		softint_init(ci);
    272 		xc_init_cpu(ci);
    273 		pool_cache_cpu_init(ci);
    274 		selsysinit(ci);
    275 		percpu_init_cpu(ci);
    276 	}
    277 
    278 	sysctl_init();
    279 	kqueue_init();
    280 	iostat_init();
    281 	uid_init();
    282 	fd_sys_init();
    283 	module_init();
    284 	devsw_init();
    285 	pipe_init();
    286 
    287 	/* these do nothing if not present */
    288 	rump_vfs_init();
    289 	rump_net_init();
    290 	rump_dev_init();
    291 	cold = 0;
    292 
    293 	/* aieeeedondest */
    294 	if (rump_threads) {
    295 		if (workqueue_create(&uvm.aiodone_queue, "aiodoned",
    296 		    rump_aiodone_worker, NULL, 0, 0, WQ_MPSAFE))
    297 			panic("aiodoned");
    298 	}
    299 
    300 	sysctl_finalize();
    301 
    302 	rumpuser_dl_module_bootstrap(rump_module_init, rump_kernelfsym_load);
    303 
    304 	rumpuser_gethostname(hostname, MAXHOSTNAMELEN, &error);
    305 	hostnamelen = strlen(hostname);
    306 
    307 	sigemptyset(&sigcantmask);
    308 
    309 	lwp0.l_fd = proc0.p_fd = fd_init(&rump_filedesc0);
    310 
    311 	if (rump_threads)
    312 		vmem_rehash_start();
    313 
    314 	rump_unschedule();
    315 
    316 	return 0;
    317 }
    318 
    319 /* maybe support sys_reboot some day for remote shutdown */
    320 void
    321 rump_reboot(int howto)
    322 {
    323 
    324 	/* dump means we really take the dive here */
    325 	if ((howto & RB_DUMP) || panicstr) {
    326 		rumpuser_exit(RUMPUSER_PANIC);
    327 		/*NOTREACHED*/
    328 	}
    329 
    330 	/* try to sync */
    331 	if (!((howto & RB_NOSYNC) || panicstr)) {
    332 		rump_vfs_fini();
    333 	}
    334 
    335 	/* your wish is my command */
    336 	if (howto & RB_HALT) {
    337 		for (;;) {
    338 			uint64_t sec = 5, nsec = 0;
    339 			int error;
    340 
    341 			rumpuser_nanosleep(&sec, &nsec, &error);
    342 		}
    343 	}
    344 	rump_inited = -1;
    345 }
    346 
    347 struct uio *
    348 rump_uio_setup(void *buf, size_t bufsize, off_t offset, enum rump_uiorw rw)
    349 {
    350 	struct uio *uio;
    351 	enum uio_rw uiorw;
    352 
    353 	switch (rw) {
    354 	case RUMPUIO_READ:
    355 		uiorw = UIO_READ;
    356 		break;
    357 	case RUMPUIO_WRITE:
    358 		uiorw = UIO_WRITE;
    359 		break;
    360 	default:
    361 		panic("%s: invalid rw %d", __func__, rw);
    362 	}
    363 
    364 	uio = kmem_alloc(sizeof(struct uio), KM_SLEEP);
    365 	uio->uio_iov = kmem_alloc(sizeof(struct iovec), KM_SLEEP);
    366 
    367 	uio->uio_iov->iov_base = buf;
    368 	uio->uio_iov->iov_len = bufsize;
    369 
    370 	uio->uio_iovcnt = 1;
    371 	uio->uio_offset = offset;
    372 	uio->uio_resid = bufsize;
    373 	uio->uio_rw = uiorw;
    374 	uio->uio_vmspace = UIO_VMSPACE_SYS;
    375 
    376 	return uio;
    377 }
    378 
    379 size_t
    380 rump_uio_getresid(struct uio *uio)
    381 {
    382 
    383 	return uio->uio_resid;
    384 }
    385 
    386 off_t
    387 rump_uio_getoff(struct uio *uio)
    388 {
    389 
    390 	return uio->uio_offset;
    391 }
    392 
    393 size_t
    394 rump_uio_free(struct uio *uio)
    395 {
    396 	size_t resid;
    397 
    398 	resid = uio->uio_resid;
    399 	kmem_free(uio->uio_iov, sizeof(*uio->uio_iov));
    400 	kmem_free(uio, sizeof(*uio));
    401 
    402 	return resid;
    403 }
    404 
    405 static pid_t nextpid = 1;
    406 struct lwp *
    407 rump_newproc_switch()
    408 {
    409 	struct lwp *l;
    410 	pid_t mypid;
    411 
    412 	mypid = atomic_inc_uint_nv(&nextpid);
    413 	if (__predict_false(mypid == 0))
    414 		mypid = atomic_inc_uint_nv(&nextpid);
    415 
    416 	l = rump_lwp_alloc(mypid, 0);
    417 	rump_lwp_switch(l);
    418 
    419 	return l;
    420 }
    421 
    422 struct lwp *
    423 rump_lwp_alloc_and_switch(pid_t pid, lwpid_t lid)
    424 {
    425 	struct lwp *l;
    426 
    427 	l = rump_lwp_alloc(pid, lid);
    428 	rump_lwp_switch(l);
    429 
    430 	return l;
    431 }
    432 
    433 struct lwp *
    434 rump_lwp_alloc(pid_t pid, lwpid_t lid)
    435 {
    436 	struct lwp *l;
    437 	struct proc *p;
    438 
    439 	l = kmem_zalloc(sizeof(*l), KM_SLEEP);
    440 	if (pid != 0) {
    441 		p = kmem_zalloc(sizeof(*p), KM_SLEEP);
    442 		if (rump_proc_vfs_init)
    443 			rump_proc_vfs_init(p);
    444 		p->p_stats = &rump_stats;
    445 		p->p_limit = &rump_limits;
    446 		p->p_pid = pid;
    447 		p->p_vmspace = &rump_vmspace;
    448 		p->p_emul = &emul_rump;
    449 		p->p_fd = fd_init(NULL);
    450 		p->p_lock = mutex_obj_alloc(MUTEX_DEFAULT, IPL_NONE);
    451 		l->l_cred = rump_cred_suserget();
    452 	} else {
    453 		p = &proc0;
    454 		l->l_cred = rump_susercred;
    455 	}
    456 
    457 	l->l_proc = p;
    458 	l->l_lid = lid;
    459 	l->l_fd = p->p_fd;
    460 	l->l_cpu = NULL;
    461 
    462 	return l;
    463 }
    464 
    465 void
    466 rump_lwp_switch(struct lwp *newlwp)
    467 {
    468 	struct lwp *l = curlwp;
    469 
    470 	rumpuser_set_curlwp(NULL);
    471 	newlwp->l_cpu = l->l_cpu;
    472 	newlwp->l_mutex = l->l_mutex;
    473 	l->l_mutex = NULL;
    474 	l->l_cpu = NULL;
    475 	rumpuser_set_curlwp(newlwp);
    476 	if (l->l_flag & LW_WEXIT)
    477 		rump_lwp_free(l);
    478 }
    479 
    480 /* XXX: this has effect only on non-pid0 lwps */
    481 void
    482 rump_lwp_release(struct lwp *l)
    483 {
    484 	struct proc *p;
    485 
    486 	p = l->l_proc;
    487 	if (p->p_pid != 0) {
    488 		mutex_obj_free(p->p_lock);
    489 		fd_free();
    490 		if (rump_proc_vfs_release)
    491 			rump_proc_vfs_release(p);
    492 		rump_cred_put(l->l_cred);
    493 		kmem_free(p, sizeof(*p));
    494 	}
    495 	KASSERT((l->l_flag & LW_WEXIT) == 0);
    496 	l->l_flag |= LW_WEXIT;
    497 }
    498 
    499 void
    500 rump_lwp_free(struct lwp *l)
    501 {
    502 
    503 	KASSERT(l->l_flag & LW_WEXIT);
    504 	KASSERT(l->l_mutex == NULL);
    505 	kmem_free(l, sizeof(*l));
    506 }
    507 
    508 struct lwp *
    509 rump_lwp_curlwp(void)
    510 {
    511 	struct lwp *l = curlwp;
    512 
    513 	if (l->l_flag & LW_WEXIT)
    514 		return NULL;
    515 	return l;
    516 }
    517 
    518 /* rump private.  NEEDS WORK! */
    519 void
    520 rump_set_vmspace(struct vmspace *vm)
    521 {
    522 	struct proc *p = curproc;
    523 
    524 	p->p_vmspace = vm;
    525 }
    526 
    527 kauth_cred_t
    528 rump_cred_create(uid_t uid, gid_t gid, size_t ngroups, gid_t *groups)
    529 {
    530 	kauth_cred_t cred;
    531 	int rv;
    532 
    533 	cred = kauth_cred_alloc();
    534 	kauth_cred_setuid(cred, uid);
    535 	kauth_cred_seteuid(cred, uid);
    536 	kauth_cred_setsvuid(cred, uid);
    537 	kauth_cred_setgid(cred, gid);
    538 	kauth_cred_setgid(cred, gid);
    539 	kauth_cred_setegid(cred, gid);
    540 	kauth_cred_setsvgid(cred, gid);
    541 	rv = kauth_cred_setgroups(cred, groups, ngroups, 0, UIO_SYSSPACE);
    542 	/* oh this is silly.  and by "this" I mean kauth_cred_setgroups() */
    543 	assert(rv == 0);
    544 
    545 	return cred;
    546 }
    547 
    548 void
    549 rump_cred_put(kauth_cred_t cred)
    550 {
    551 
    552 	kauth_cred_free(cred);
    553 }
    554 
    555 kauth_cred_t
    556 rump_cred_suserget(void)
    557 {
    558 
    559 	kauth_cred_hold(rump_susercred);
    560 	return rump_susercred;
    561 }
    562 
    563 /*
    564  * Return the next system lwpid
    565  */
    566 lwpid_t
    567 rump_nextlid(void)
    568 {
    569 	lwpid_t retid;
    570 
    571 	mutex_enter(proc0.p_lock);
    572 	/*
    573 	 * Take next one, don't return 0
    574 	 * XXX: most likely we'll have collisions in case this
    575 	 * wraps around.
    576 	 */
    577 	if (++proc0.p_nlwpid == 0)
    578 		++proc0.p_nlwpid;
    579 	retid = proc0.p_nlwpid;
    580 	mutex_exit(proc0.p_lock);
    581 
    582 	return retid;
    583 }
    584 
    585 #define ERROUT(err) do { rv = err; goto out; } while (/*CONSTCOND*/0)
    586 int
    587 rump_module_init(struct modinfo *mi, prop_dictionary_t props)
    588 {
    589 	struct module *mod;
    590 	int rv;
    591 
    592 	/* module_dummy */
    593 	if (mi->mi_name == NULL)
    594 		return EINVAL;
    595 
    596 	mutex_enter(&module_lock);
    597 	if (module_lookup(mi->mi_name))
    598 		ERROUT(EEXIST);
    599 
    600 	if (!module_compatible(mi->mi_version, __NetBSD_Version__))
    601 		ERROUT(EPROGMISMATCH);
    602 
    603 	rv = mi->mi_modcmd(MODULE_CMD_INIT, props);
    604 	if (rv == 0) {
    605 		mod = kmem_zalloc(sizeof(*mod), KM_SLEEP);
    606 		mod->mod_info = mi;
    607 		module_enqueue(mod);
    608 		if (mi->mi_class == MODULE_CLASS_SECMODEL)
    609 			secmodel_register();
    610 	}
    611 
    612  out:
    613 	mutex_exit(&module_lock);
    614 	return rv;
    615 }
    616 
    617 int
    618 rump_module_fini(struct modinfo *mi)
    619 {
    620 	int rv;
    621 
    622 	rv = mi->mi_modcmd(MODULE_CMD_FINI, NULL);
    623 	if (rv == 0 && mi->mi_class == MODULE_CLASS_SECMODEL)
    624 		secmodel_deregister();
    625 
    626 	return rv;
    627 }
    628 
    629 int
    630 rump_kernelfsym_load(void *symtab, uint64_t symsize,
    631 	char *strtab, uint64_t strsize)
    632 {
    633 	static int inited = 0;
    634 	Elf64_Ehdr ehdr;
    635 
    636 	if (inited)
    637 		return EBUSY;
    638 	inited = 1;
    639 
    640 	/*
    641 	 * Use 64bit header since it's bigger.  Shouldn't make a
    642 	 * difference, since we're passing in all zeroes anyway.
    643 	 */
    644 	memset(&ehdr, 0, sizeof(ehdr));
    645 	ksyms_addsyms_explicit(&ehdr, symtab, symsize, strtab, strsize);
    646 
    647 	return 0;
    648 }
    649 
    650 static int
    651 rump_sysproxy_local(int num, void *arg, uint8_t *data, size_t dlen,
    652 	register_t *retval)
    653 {
    654 	struct lwp *l;
    655 	struct sysent *callp;
    656 	int rv;
    657 
    658 	if (__predict_false(num >= SYS_NSYSENT))
    659 		return ENOSYS;
    660 
    661 	callp = rump_sysent + num;
    662 	rump_schedule();
    663 	l = curlwp;
    664 	rv = callp->sy_call(l, (void *)data, retval);
    665 	rump_unschedule();
    666 
    667 	return rv;
    668 }
    669 
    670 int
    671 rump_boot_gethowto()
    672 {
    673 
    674 	return boothowto;
    675 }
    676 
    677 void
    678 rump_boot_sethowto(int howto)
    679 {
    680 
    681 	boothowto = howto;
    682 }
    683 
    684 rump_sysproxy_t rump_sysproxy = rump_sysproxy_local;
    685 void *rump_sysproxy_arg;
    686 
    687 /*
    688  * This whole syscall-via-rpc is still taking form.  For example, it
    689  * may be necessary to set syscalls individually instead of lobbing
    690  * them all to the same place.  So don't think this interface is
    691  * set in stone.
    692  */
    693 int
    694 rump_sysproxy_set(rump_sysproxy_t proxy, void *arg)
    695 {
    696 
    697 	if (rump_sysproxy_arg)
    698 		return EBUSY;
    699 
    700 	rump_sysproxy_arg = arg;
    701 	rump_sysproxy = proxy;
    702 
    703 	return 0;
    704 }
    705 
    706 int
    707 rump_getversion(void)
    708 {
    709 
    710 	return __NetBSD_Version__;
    711 }
    712