/* $NetBSD: requests.c,v 1.24 2013/01/23 20:22:34 riastradh Exp $ */
/*
* Copyright (c) 2007 Antti Kantee. All Rights Reserved.
*
* Development of this software was supported by the
* Research Foundation of Helsinki University of Technology
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS
* OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
* WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
* SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#include <sys/cdefs.h>
#if !defined(lint)
__RCSID("$NetBSD: requests.c,v 1.24 2013/01/23 20:22:34 riastradh Exp $");
#endif /* !lint */
#include <sys/types.h>
#include <sys/ioctl.h>
#include <sys/queue.h>
#include <sys/socket.h>
#include <dev/putter/putter.h>
#include <assert.h>
#include <errno.h>
#include <puffs.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include "puffs_priv.h"
/*
* Read a frame from the upstream provider. First read the frame
* length and after this read the actual contents. Yes, optimize
* me some day.
*/
/*ARGSUSED*/
int
puffs__fsframe_read(struct puffs_usermount *pu, struct puffs_framebuf *pb,
int fd, int *done)
{
struct putter_hdr phdr;
void *win;
size_t howmuch, winlen, curoff;
ssize_t n;
int lenstate;
/* How much to read? */
the_next_level:
curoff = puffs_framebuf_telloff(pb);
if (curoff < sizeof(struct putter_hdr)) {
howmuch = sizeof(struct putter_hdr) - curoff;
lenstate = 1;
} else {
puffs_framebuf_getdata_atoff(pb, 0, &phdr, sizeof(phdr));
/*LINTED*/
howmuch = phdr.pth_framelen - curoff;
lenstate = 0;
}
if (puffs_framebuf_reserve_space(pb, howmuch) == -1)
return errno;
/* Read contents */
while (howmuch) {
winlen = howmuch;
curoff = puffs_framebuf_telloff(pb);
if (puffs_framebuf_getwindow(pb, curoff, &win, &winlen) == -1)
return errno;
n = read(fd, win, winlen);
switch (n) {
case 0:
return ECONNRESET;
case -1:
if (errno == EAGAIN)
return 0;
return errno;
default:
howmuch -= n;
puffs_framebuf_seekset(pb, curoff + n);
break;
}
}
if (lenstate)
goto the_next_level;
puffs_framebuf_seekset(pb, 0);
*done = 1;
return 0;
}
/*
* Write a frame upstream
*/
/*ARGSUSED*/
int
puffs__fsframe_write(struct puffs_usermount *pu, struct puffs_framebuf *pb,
int fd, int *done)
{
void *win;
uint64_t flen;
size_t winlen, howmuch, curoff;
ssize_t n;
int rv;
/*
* Finalize it if we haven't written anything yet (or we're still
* attempting to write the first byte)
*
* XXX: this shouldn't be here
*/
if (puffs_framebuf_telloff(pb) == 0) {
struct puffs_req *preq;
winlen = sizeof(struct puffs_req);
rv = puffs_framebuf_getwindow(pb, 0, (void *)&preq, &winlen);
if (rv == -1)
return errno;
preq->preq_pth.pth_framelen = flen = preq->preq_buflen;
} else {
struct putter_hdr phdr;
puffs_framebuf_getdata_atoff(pb, 0, &phdr, sizeof(phdr));
flen = phdr.pth_framelen;
}
/*
* Then write it. Chances are if we are talking to the kernel it'll
* just shlosh in all at once, but if we're e.g. talking to the
* network it might take a few tries.
*/
/*LINTED*/
howmuch = flen - puffs_framebuf_telloff(pb);
while (howmuch) {
winlen = howmuch;
curoff = puffs_framebuf_telloff(pb);
if (puffs_framebuf_getwindow(pb, curoff, &win, &winlen) == -1)
return errno;
/*
* XXX: we know from the framebuf implementation that we
* will always managed to map the entire window. But if
* that changes, this will catch it. Then we can do stuff
* iov stuff instead.
*/
assert(winlen == howmuch);
/* XXX: want NOSIGNAL if writing to a pipe */
#if 0
n = send(fd, win, winlen, MSG_NOSIGNAL);
#else
n = write(fd, win, winlen);
#endif
switch (n) {
case 0:
return ECONNRESET;
case -1:
if (errno == EAGAIN)
return 0;
return errno;
default:
howmuch -= n;
puffs_framebuf_seekset(pb, curoff + n);
break;
}
}
*done = 1;
return 0;
}
/*
* Compare if "pb1" is a response to a previously sent frame pb2.
* More often than not "pb1" is not a response to anything but
* rather a fresh request from the kernel.
*/
/*ARGSUSED*/
int
puffs__fsframe_cmp(struct puffs_usermount *pu,
struct puffs_framebuf *pb1, struct puffs_framebuf *pb2, int *notresp)
{
struct puffs_req *preq1, *preq2;
size_t winlen;
int rv;
/* map incoming preq */
winlen = sizeof(struct puffs_req);
rv = puffs_framebuf_getwindow(pb1, 0, (void *)&preq1, &winlen);
assert(rv == 0); /* frames are always at least puffs_req in size */
assert(winlen == sizeof(struct puffs_req));
/*
* Check if this is not a response in this slot. That's the
* likely case.
*/
if ((preq1->preq_opclass & PUFFSOPFLAG_ISRESPONSE) == 0) {
*notresp = 1;
return 0;
}
/* map second preq */
winlen = sizeof(struct puffs_req);
rv = puffs_framebuf_getwindow(pb2, 0, (void *)&preq2, &winlen);
assert(rv == 0); /* frames are always at least puffs_req in size */
assert(winlen == sizeof(struct puffs_req));
/* then compare: resid equal? */
return preq1->preq_id != preq2->preq_id;
}
void
puffs__fsframe_gotframe(struct puffs_usermount *pu, struct puffs_framebuf *pb)
{
puffs_framebuf_seekset(pb, 0);
puffs__ml_dispatch(pu, pb);
}
