xref: /netbsd-src/sys/rump/kern/lib/libsysproxy/sysproxy.c (revision 946379e7b37692fc43f68eb0d1c10daa0a7f3b6c)
1 /*	$NetBSD: sysproxy.c,v 1.3 2015/04/18 15:49:18 pooka Exp $	*/
2 
3 /*
4  * Copyright (c) 2010, 2011 Antti Kantee.  All Rights Reserved.
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  * 1. Redistributions of source code must retain the above copyright
10  *    notice, this list of conditions and the following disclaimer.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in the
13  *    documentation and/or other materials provided with the distribution.
14  *
15  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS
16  * OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
17  * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
18  * DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
19  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
20  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
21  * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
22  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
23  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
24  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
25  * SUCH DAMAGE.
26  */
27 
28 #include <sys/cdefs.h>
29 __KERNEL_RCSID(0, "$NetBSD: sysproxy.c,v 1.3 2015/04/18 15:49:18 pooka Exp $");
30 
31 #include <sys/param.h>
32 #include <sys/filedesc.h>
33 #include <sys/kmem.h>
34 #include <sys/syscall.h>
35 #include <sys/syscallvar.h>
36 #include <sys/systm.h>
37 #include <sys/xcall.h>
38 
39 #define _RUMP_SYSPROXY
40 #include <rump/rumpuser.h>
41 
42 #include "rump_private.h"
43 
44 int
45 rump_init_server(const char *url)
46 {
47 
48 	return rumpuser_sp_init(url, ostype, osrelease, MACHINE);
49 }
50 
51 static pid_t
52 hyp_getpid(void)
53 {
54 
55 	return curproc->p_pid;
56 }
57 
58 static int
59 hyp_syscall(int num, void *arg, long *retval)
60 {
61 	register_t regrv[2] = {0, 0};
62 	struct lwp *l;
63 	struct sysent *callp;
64 	int rv;
65 
66 	if (__predict_false(num >= SYS_NSYSENT))
67 		return ENOSYS;
68 
69 	/* XXX: always uses native syscall vector */
70 	callp = rump_sysent + num;
71 	l = curlwp;
72 	rv = sy_invoke(callp, l, (void *)arg, regrv, num);
73 	retval[0] = regrv[0];
74 	retval[1] = regrv[1];
75 
76 	return rv;
77 }
78 
79 static struct pmap remotepmap;
80 
81 static int
82 hyp_rfork(void *priv, int flags, const char *comm)
83 {
84 	struct rump_spctl *spctl;
85 	struct vmspace *vm;
86 	struct proc *p;
87 	struct lwp *l;
88 	int error;
89 	bool initfds;
90 
91 	/*
92 	 * If we are forking off of pid 1, initialize file descriptors.
93 	 */
94 	l = curlwp;
95 	if (l->l_proc->p_pid == 1) {
96 		KASSERT(flags == RUMP_RFFD_CLEAR);
97 		initfds = true;
98 	} else {
99 		initfds = false;
100 	}
101 
102 	/*
103 	 * Since it's a proxy proc, we create a vmspace for it.
104 	 */
105 	spctl = kmem_zalloc(sizeof(*spctl), KM_SLEEP);
106 	vm = &spctl->spctl_vm;
107 	uvmspace_init(vm, &remotepmap, 0, 0, false);
108 	spctl->spctl = priv;
109 
110 	if ((error = rump_lwproc_rfork_vmspace(vm, flags)) != 0) {
111 		kmem_free(vm, sizeof(*vm));
112 		return error;
113 	}
114 
115 	/*
116 	 * We forked in this routine, so cannot use curlwp (const)
117 	 */
118 	l = rump_lwproc_curlwp();
119 	p = l->l_proc;
120 
121 	if (comm)
122 		strlcpy(p->p_comm, comm, sizeof(p->p_comm));
123 	if (initfds)
124 		rump_consdev_init();
125 
126 	return 0;
127 }
128 
129 /*
130  * Order all lwps in a process to exit.  does *not* wait for them to drain.
131  */
132 static void
133 hyp_lwpexit(void)
134 {
135 	struct proc *p = curproc;
136 	uint64_t where;
137 	struct lwp *l;
138 
139 	mutex_enter(p->p_lock);
140 	/*
141 	 * First pass: mark all lwps in the process with LW_RUMP_QEXIT
142 	 * so that they know they should exit.
143 	 */
144 	LIST_FOREACH(l, &p->p_lwps, l_sibling) {
145 		if (l == curlwp)
146 			continue;
147 		l->l_flag |= LW_RUMP_QEXIT;
148 	}
149 	mutex_exit(p->p_lock);
150 
151 	/*
152 	 * Next, make sure everyone on all CPUs sees our status
153 	 * update.  This keeps threads inside cv_wait() and makes
154 	 * sure we don't access a stale cv pointer later when
155 	 * we wake up the threads.
156 	 */
157 
158 	where = xc_broadcast(0, (xcfunc_t)nullop, NULL, NULL);
159 	xc_wait(where);
160 
161 	/*
162 	 * Ok, all lwps are either:
163 	 *  1) not in the cv code
164 	 *  2) sleeping on l->l_private
165 	 *  3) sleeping on p->p_waitcv
166 	 *
167 	 * Either way, l_private is stable until we set PS_RUMP_LWPEXIT
168 	 * in p->p_sflag.
169 	 */
170 
171 	mutex_enter(p->p_lock);
172 	LIST_FOREACH(l, &p->p_lwps, l_sibling) {
173 		if (l->l_private)
174 			cv_broadcast(l->l_private);
175 	}
176 	p->p_sflag |= PS_RUMP_LWPEXIT;
177 	cv_broadcast(&p->p_waitcv);
178 	mutex_exit(p->p_lock);
179 }
180 
181 /*
182  * Notify process that all threads have been drained and exec is complete.
183  */
184 static void
185 hyp_execnotify(const char *comm)
186 {
187 	struct proc *p = curproc;
188 
189 	fd_closeexec();
190 	mutex_enter(p->p_lock);
191 	KASSERT(p->p_nlwps == 1 && p->p_sflag & PS_RUMP_LWPEXIT);
192 	p->p_sflag &= ~PS_RUMP_LWPEXIT;
193 	mutex_exit(p->p_lock);
194 	strlcpy(p->p_comm, comm, sizeof(p->p_comm));
195 }
196 
197 /*
198  * Initialize interface pointers since component is present.
199  */
200 RUMP_COMPONENT(RUMP_COMPONENT_KERN)
201 {
202 
203 	rump_sysproxy_ops.rspo_copyin		= rumpuser_sp_copyin;
204 	rump_sysproxy_ops.rspo_copyinstr	= rumpuser_sp_copyinstr;
205 	rump_sysproxy_ops.rspo_copyout		= rumpuser_sp_copyout;
206 	rump_sysproxy_ops.rspo_copyoutstr	= rumpuser_sp_copyoutstr;
207 	rump_sysproxy_ops.rspo_anonmmap		= rumpuser_sp_anonmmap;
208 	rump_sysproxy_ops.rspo_raise		= rumpuser_sp_raise;
209 	rump_sysproxy_ops.rspo_fini		= rumpuser_sp_fini;
210 
211 	rump_sysproxy_ops.rspo_hyp_getpid	= hyp_getpid;
212 	rump_sysproxy_ops.rspo_hyp_syscall	= hyp_syscall;
213 	rump_sysproxy_ops.rspo_hyp_rfork	= hyp_rfork;
214 	rump_sysproxy_ops.rspo_hyp_lwpexit	= hyp_lwpexit;
215 	rump_sysproxy_ops.rspo_hyp_execnotify	= hyp_execnotify;
216 }
217