xref: /netbsd-src/sys/rump/fs/lib/libsyspuffs/puffs_rumpglue.c (revision b1c86f5f087524e68db12794ee9c3e3da1ab17a0)
1 /*	$NetBSD: puffs_rumpglue.c,v 1.11 2009/10/14 18:18:53 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 1.11 2009/10/14 18:18:53 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 #include "rump_vfs_private.h"
48 
49 void putterattach(void); /* XXX: from autoconf */
50 dev_type_open(puttercdopen);
51 
52 struct ptargs {
53 	int comfd;
54 	int fpfd;
55 	struct filedesc *fdp;
56 };
57 
58 #define BUFSIZE (64*1024)
59 extern int hz;
60 
61 /*
62  * Read requests from /dev/puffs and forward them to comfd
63  *
64  * XXX: the init detection is really sucky, but let's not
65  * waste too much energy for a better one here
66  */
67 static void
68 readthread(void *arg)
69 {
70 	struct ptargs *pap = arg;
71 	struct file *fp;
72 	register_t rv;
73 	char *buf;
74 	off_t off;
75 	int error, inited;
76 
77 	buf = kmem_alloc(BUFSIZE, KM_SLEEP);
78 	inited = 0;
79 
80  retry:
81 	kpause(NULL, 0, hz/4, NULL);
82 
83 	for (;;) {
84 		ssize_t n;
85 
86 		off = 0;
87 		fp = fd_getfile(pap->fpfd);
88 		error = dofileread(pap->fpfd, fp, buf, BUFSIZE,
89 		    &off, 0, &rv);
90 		if (error) {
91 			if (error == ENOENT && inited == 0)
92 				goto retry;
93 			if (error == ENXIO)
94 				break;
95 			panic("fileread failed: %d", error);
96 		}
97 		inited = 1;
98 
99 		while (rv) {
100 			n = rumpuser_write(pap->comfd, buf, rv, &error);
101 			if (n == -1)
102 				panic("fileread failed: %d", error);
103 			if (n == 0)
104 				panic("fileread failed: closed");
105 			rv -= n;
106 		}
107 	}
108 
109 	kthread_exit(0);
110 }
111 
112 /* Read requests from comfd and proxy them to /dev/puffs */
113 static void
114 writethread(void *arg)
115 {
116 	struct ptargs *pap = arg;
117 	struct file *fp;
118 	struct putter_hdr *phdr;
119 	register_t rv;
120 	char *buf;
121 	off_t off;
122 	size_t toread;
123 	int error;
124 
125 	buf = kmem_alloc(BUFSIZE, KM_SLEEP);
126 	phdr = (struct putter_hdr *)buf;
127 
128 	for (;;) {
129 		ssize_t n;
130 
131 		/*
132 		 * Need to write everything to the "kernel" in one chunk,
133 		 * so make sure we have it here.
134 		 */
135 		off = 0;
136 		toread = sizeof(struct putter_hdr);
137 		do {
138 			n = rumpuser_read(pap->comfd, buf+off, toread, &error);
139 			if (n <= 0) {
140 				if (n == 0)
141 					goto out;
142 				panic("rumpuser_read %zd %d", n, error);
143 			}
144 			off += n;
145 			if (off >= sizeof(struct putter_hdr))
146 				toread = phdr->pth_framelen - off;
147 			else
148 				toread = off - sizeof(struct putter_hdr);
149 		} while (toread);
150 
151 		off = 0;
152 		rv = 0;
153 		fp = fd_getfile(pap->fpfd);
154 		error = dofilewrite(pap->fpfd, fp, buf, phdr->pth_framelen,
155 		    &off, 0, &rv);
156 		if (error == ENXIO)
157 			goto out;
158 		KASSERT(rv == phdr->pth_framelen);
159 	}
160  out:
161 
162 	kthread_exit(0);
163 }
164 
165 int
166 rump_syspuffs_glueinit(int fd, int *newfd)
167 {
168 	struct ptargs *pap;
169 	int rv;
170 
171 	if ((rv = rump_init()) != 0)
172 		return rv;
173 
174 	putterattach();
175 	rv = puttercdopen(makedev(178, 0), 0, 0, curlwp);
176 	if (rv && rv != EMOVEFD)
177 		return rv;
178 
179 	pap = kmem_alloc(sizeof(struct ptargs), KM_SLEEP);
180 	pap->comfd = fd;
181 	pap->fpfd = curlwp->l_dupfd;
182 	pap->fdp = curlwp->l_proc->p_fd;
183 
184 	kthread_create(PRI_NONE, 0, NULL, readthread, pap, NULL, "rputter");
185 	kthread_create(PRI_NONE, 0, NULL, writethread, pap, NULL, "wputter");
186 
187 	*newfd = curlwp->l_dupfd;
188 	return 0;
189 }
190