xref: /netbsd-src/sys/rump/fs/lib/libsyspuffs/puffs_rumpglue.c (revision 404fbe5fb94ca1e054339640cabb2801ce52dd30)
1 /*	$NetBSD: puffs_rumpglue.c,v 1.9 2009/01/08 03:27:10 pooka Exp $	*/
2 
3 /*
4  * Copyright (c) 2008 Antti Kantee.  All Rights Reserved.
5  *
6  * Development of this software was supported by the
7  * Research Foundation of Helsinki University of Technology
8  *
9  * Redistribution and use in source and binary forms, with or without
10  * modification, are permitted provided that the following conditions
11  * are met:
12  * 1. Redistributions of source code must retain the above copyright
13  *    notice, this list of conditions and the following disclaimer.
14  * 2. Redistributions in binary form must reproduce the above copyright
15  *    notice, this list of conditions and the following disclaimer in the
16  *    documentation and/or other materials provided with the distribution.
17  *
18  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS
19  * OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
20  * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
21  * DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
22  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
23  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
24  * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
25  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
26  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
27  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
28  * SUCH DAMAGE.
29  */
30 
31 #include <sys/cdefs.h>
32 __KERNEL_RCSID(0, "$NetBSD: puffs_rumpglue.c,v 1.9 2009/01/08 03:27:10 pooka Exp $");
33 
34 #include <sys/param.h>
35 #include <sys/conf.h>
36 #include <sys/file.h>
37 #include <sys/filedesc.h>
38 #include <sys/kthread.h>
39 #include <sys/mount.h>
40 
41 #include <dev/putter/putter.h>
42 #include <dev/putter/putter_sys.h>
43 
44 #include <rump/rump.h>
45 #include <rump/rumpuser.h>
46 
47 void putterattach(void); /* XXX: from autoconf */
48 dev_type_open(puttercdopen);
49 
50 struct ptargs {
51 	int comfd;
52 	int fpfd;
53 	struct filedesc *fdp;
54 };
55 
56 #define BUFSIZE (64*1024)
57 extern int hz;
58 
59 /*
60  * Read requests from /dev/puffs and forward them to comfd
61  *
62  * XXX: the init detection is really sucky, but let's not
63  * waste too much energy for a better one here
64  */
65 static void
66 readthread(void *arg)
67 {
68 	struct ptargs *pap = arg;
69 	struct file *fp;
70 	register_t rv;
71 	char *buf;
72 	off_t off;
73 	int error, inited;
74 
75 	buf = kmem_alloc(BUFSIZE, KM_SLEEP);
76 	inited = 0;
77 
78  retry:
79 	kpause(NULL, 0, hz/4, NULL);
80 
81 	for (;;) {
82 		ssize_t n;
83 
84 		off = 0;
85 		fp = fd_getfile(pap->fpfd);
86 		error = dofileread(pap->fpfd, fp, buf, BUFSIZE,
87 		    &off, 0, &rv);
88 		if (error) {
89 			if (error == ENOENT && inited == 0)
90 				goto retry;
91 			if (error == ENXIO)
92 				break;
93 			panic("fileread failed: %d", error);
94 		}
95 		inited = 1;
96 
97 		while (rv) {
98 			n = rumpuser_write(pap->comfd, buf, rv, &error);
99 			if (n == -1)
100 				panic("fileread failed: %d", error);
101 			if (n == 0)
102 				panic("fileread failed: closed");
103 			rv -= n;
104 		}
105 	}
106 
107 	kthread_exit(0);
108 }
109 
110 /* Read requests from comfd and proxy them to /dev/puffs */
111 static void
112 writethread(void *arg)
113 {
114 	struct ptargs *pap = arg;
115 	struct file *fp;
116 	struct putter_hdr *phdr;
117 	register_t rv;
118 	char *buf;
119 	off_t off;
120 	size_t toread;
121 	int error;
122 
123 	buf = kmem_alloc(BUFSIZE, KM_SLEEP);
124 	phdr = (struct putter_hdr *)buf;
125 
126 	for (;;) {
127 		ssize_t n;
128 
129 		/*
130 		 * Need to write everything to the "kernel" in one chunk,
131 		 * so make sure we have it here.
132 		 */
133 		off = 0;
134 		toread = sizeof(struct putter_hdr);
135 		do {
136 			n = rumpuser_read(pap->comfd, buf+off, toread, &error);
137 			if (n <= 0) {
138 				if (n == 0)
139 					goto out;
140 				panic("rumpuser_read %zd %d", n, error);
141 			}
142 			off += n;
143 			if (off >= sizeof(struct putter_hdr))
144 				toread = phdr->pth_framelen - off;
145 			else
146 				toread = off - sizeof(struct putter_hdr);
147 		} while (toread);
148 
149 		off = 0;
150 		rv = 0;
151 		fp = fd_getfile(pap->fpfd);
152 		error = dofilewrite(pap->fpfd, fp, buf, phdr->pth_framelen,
153 		    &off, 0, &rv);
154 		if (error == ENXIO)
155 			goto out;
156 		KASSERT(rv == phdr->pth_framelen);
157 	}
158  out:
159 
160 	kthread_exit(0);
161 }
162 
163 int
164 rump_syspuffs_glueinit(int fd, int *newfd)
165 {
166 	struct ptargs *pap;
167 	int rv;
168 
169 	if ((rv = rump_init()) != 0)
170 		return rv;
171 
172 	putterattach();
173 	rv = puttercdopen(makedev(178, 0), 0, 0, curlwp);
174 	if (rv && rv != EMOVEFD)
175 		return rv;
176 
177 	pap = kmem_alloc(sizeof(struct ptargs), KM_SLEEP);
178 	pap->comfd = fd;
179 	pap->fpfd = curlwp->l_dupfd;
180 	pap->fdp = curlwp->l_proc->p_fd;
181 
182 	kthread_create(PRI_NONE, 0, NULL, readthread, pap, NULL, "rputter");
183 	kthread_create(PRI_NONE, 0, NULL, writethread, pap, NULL, "wputter");
184 
185 	*newfd = curlwp->l_dupfd;
186 	return 0;
187 }
188