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puffs_rumpglue.c revision 1.10 
      1 /*	$NetBSD: puffs_rumpglue.c,v 1.10 2009/10/14 17:29:19 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 1.10 2009/10/14 17:29:19 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 rumppriv_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