NetBSD-5.0.2/sys/dev/pud/pud.c
/* $NetBSD: pud.c,v 1.6 2007/11/28 17:01:59 pooka 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>
__KERNEL_RCSID(0, "$NetBSD: pud.c,v 1.6 2007/11/28 17:01:59 pooka Exp $");
#include <sys/param.h>
#include <sys/conf.h>
#include <sys/kmem.h>
#include <sys/poll.h>
#include <sys/queue.h>
#include <dev/pud/pud_sys.h>
#include <dev/putter/putter_sys.h>
void pudattach(void);
static int pud_putter_getout(void *, size_t, int, uint8_t **,
size_t *, void **);
static void pud_putter_releaseout(void *, void *, int);
static int pud_putter_dispatch(void *, struct putter_hdr *);
static size_t pud_putter_waitcount(void *);
static int pud_putter_close(void *);
struct putter_ops pud_putter = {
.pop_getout = pud_putter_getout,
.pop_releaseout = pud_putter_releaseout,
.pop_waitcount = pud_putter_waitcount,
.pop_dispatch = pud_putter_dispatch,
.pop_close = pud_putter_close,
};
extern struct bdevsw pud_bdevsw;
extern struct cdevsw pud_cdevsw;
kmutex_t pud_mtx;
static LIST_HEAD(, pud_dev) pudlist = LIST_HEAD_INITIALIZER(pudlist);
static uint64_t
nextreq(struct pud_dev *pd)
{
uint64_t rv;
mutex_enter(&pd->pd_mtx);
rv = pd->pd_nextreq++;
mutex_exit(&pd->pd_mtx);
return rv;
}
static int
pud_putter_getout(void *this, size_t maxsize, int nonblock,
uint8_t **data, size_t *dlen, void **cookie)
{
struct pud_dev *pd = this;
struct pud_touser *putp;
int error = 0;
mutex_enter(&pd->pd_mtx);
for (;;) {
if (TAILQ_EMPTY(&pd->pd_waitq_req)) {
if (nonblock) {
error = EWOULDBLOCK;
break;
}
error = cv_wait_sig(&pd->pd_waitq_req_cv, &pd->pd_mtx);
if (error)
break;
else
continue;
}
putp = TAILQ_FIRST(&pd->pd_waitq_req);
TAILQ_REMOVE(&pd->pd_waitq_req, putp, pt_entries);
KASSERT(error == 0);
break;
}
mutex_exit(&pd->pd_mtx);
if (error == 0) {
*data = (uint8_t *)putp->pt_pdr;
*dlen = putp->pt_pdr->pdr_pth.pth_framelen;
*cookie = putp;
}
return error;
}
static void
pud_putter_releaseout(void *this, void *cookie, int status)
{
struct pud_dev *pd = this;
struct pud_touser *putp = cookie;
mutex_enter(&pd->pd_mtx);
TAILQ_INSERT_TAIL(&pd->pd_waitq_resp, putp, pt_entries);
mutex_exit(&pd->pd_mtx);
}
static size_t
pud_putter_waitcount(void *this)
{
struct pud_dev *pd = this;
size_t rv;
mutex_enter(&pd->pd_mtx);
rv = pd->pd_waitcount;
mutex_exit(&pd->pd_mtx);
return rv;
}
static int
pudop_dev(struct pud_dev *pd, struct pud_req *pdr)
{
struct putter_hdr *pth = (void *)pdr;
struct pud_touser *putp;
mutex_enter(&pd->pd_mtx);
TAILQ_FOREACH(putp, &pd->pd_waitq_resp, pt_entries)
if (putp->pt_pdr->pdr_reqid == pdr->pdr_reqid)
break;
if (putp == NULL) {
mutex_exit(&pd->pd_mtx);
return EINVAL;
}
TAILQ_REMOVE(&pd->pd_waitq_resp, putp, pt_entries);
mutex_exit(&pd->pd_mtx);
if (pth->pth_framelen > putp->pt_pdr->pdr_len) {
return EINVAL;
}
memcpy(putp->pt_pdr, pth, pth->pth_framelen);
cv_signal(&putp->pt_cv);
return 0;
}
/*
* Register our major number. Always register char device functions,
* register block devices optionally.
*
* XXX: no way to configure "any major you like" currently.
*/
static int
pudconf_reg(struct pud_dev *pd, struct pud_conf_reg *pcr)
{
struct bdevsw *bsw;
int cmajor, bmajor, error;
if (pcr->pm_version != (PUD_DEVELVERSION | PUD_VERSION)) {
printf("pud version mismatch %d vs %d\n",
pcr->pm_version & ~PUD_DEVELVERSION, PUD_VERSION);
return EINVAL; /* XXX */
}
cmajor = major(pcr->pm_regdev);
if (pcr->pm_flags & PUD_CONFFLAG_BDEV) {
bsw = &pud_bdevsw;
bmajor = cmajor;
} else {
bsw = NULL;
bmajor = -1;
}
pcr->pm_devname[PUD_DEVNAME_MAX] = '\0';
error = devsw_attach(pcr->pm_devname, bsw, &bmajor,
&pud_cdevsw, &cmajor);
if (error == 0)
pd->pd_dev = pcr->pm_regdev;
return error;
}
static int
pudop_conf(struct pud_dev *pd, struct pud_req *pdr)
{
int rv;
switch (pdr->pdr_reqtype) {
case PUD_CONF_REG:
rv = pudconf_reg(pd, (struct pud_conf_reg *)pdr);
break;
case PUD_CONF_DEREG:
/* unimplemented */
rv = 0;
break;
default:
rv = EINVAL;
break;
}
return rv;
}
static int
pud_putter_dispatch(void *this, struct putter_hdr *pth)
{
struct pud_dev *pd = this;
struct pud_req *pdr = (void *)pth;
int rv;
if (pdr->pdr_pth.pth_framelen < sizeof(struct pud_req))
return EINVAL;
switch (pdr->pdr_reqclass) {
case PUD_REQ_CDEV:
case PUD_REQ_BDEV:
rv = pudop_dev(pd, pdr);
break;
case PUD_REQ_CONF:
rv = pudop_conf(pd, pdr);
break;
default:
rv = EINVAL;
break;
}
return rv;
}
/* Device server severed the umbilical cord */
static int
pud_putter_close(void *this)
{
struct pud_dev *pd = this;
struct pud_touser *putp;
mutex_enter(&pud_mtx);
LIST_REMOVE(pd, pd_entries);
mutex_exit(&pud_mtx);
mutex_enter(&pd->pd_mtx);
while ((putp = TAILQ_FIRST(&pd->pd_waitq_req)) != NULL) {
putp->pt_pdr->pdr_rv = ENXIO;
cv_signal(&putp->pt_cv);
TAILQ_REMOVE(&pd->pd_waitq_req, putp, pt_entries);
}
while ((putp = TAILQ_FIRST(&pd->pd_waitq_resp)) != NULL) {
putp->pt_pdr->pdr_rv = ENXIO;
cv_signal(&putp->pt_cv);
TAILQ_REMOVE(&pd->pd_waitq_resp, putp, pt_entries);
}
if (pd->pd_waitcount)
cv_wait(&pd->pd_draincv, &pd->pd_mtx);
KASSERT(pd->pd_waitcount == 0);
mutex_exit(&pd->pd_mtx);
if (pd->pd_dev)
devsw_detach(&pud_bdevsw /* XXX */, &pud_cdevsw);
putter_detach(pd->pd_pi);
mutex_destroy(&pd->pd_mtx);
cv_destroy(&pd->pd_draincv);
cv_destroy(&pd->pd_waitq_req_cv);
kmem_free(pd, sizeof(struct pud_dev));
return 0;
}
struct pud_dev *
pud_dev2pud(dev_t dev)
{
struct pud_dev *pd;
mutex_enter(&pud_mtx);
LIST_FOREACH(pd, &pudlist, pd_entries)
if (major(pd->pd_dev) == major(dev))
break;
mutex_exit(&pud_mtx);
return pd;
}
/* Toss request to the device server and wait for result */
int
pud_request(dev_t dev, void *data, size_t dlen, int class, int type)
{
struct pud_touser put;
struct pud_req *pdr = data;
struct pud_dev *pd;
pd = pud_dev2pud(dev);
if (pd == NULL)
return ENXIO;
pdr->pdr_dev = dev;
pdr->pdr_len = pdr->pdr_pth.pth_framelen = dlen;
pdr->pdr_reqid = nextreq(pd);
pdr->pdr_reqclass = class;
pdr->pdr_reqtype = type;
put.pt_pdr = pdr;
cv_init(&put.pt_cv, "pudresp");
mutex_enter(&pd->pd_mtx);
pd->pd_waitcount++;
TAILQ_INSERT_TAIL(&pd->pd_waitq_req, &put, pt_entries);
putter_notify(pd->pd_pi);
cv_broadcast(&pd->pd_waitq_req_cv);
cv_wait(&put.pt_cv, &pd->pd_mtx);
if (--pd->pd_waitcount == 0)
cv_signal(&pd->pd_draincv);
mutex_exit(&pd->pd_mtx);
cv_destroy(&put.pt_cv);
return pdr->pdr_rv;
}
/* Called from putter based on minor dev number */
int
pud_config(int fd, int flags, int fmt)
{
struct pud_dev *pd;
pd = kmem_zalloc(sizeof(struct pud_dev), KM_SLEEP);
pd->pd_pi = putter_attach(curlwp->l_proc->p_pid, fd, pd, &pud_putter);
if (pd->pd_pi == NULL) {
kmem_free(pd, sizeof(struct pud_dev));
return ENOENT; /* XXX */
}
pd->pd_dev = NODEV;
mutex_init(&pd->pd_mtx, MUTEX_DEFAULT, IPL_NONE);
TAILQ_INIT(&pd->pd_waitq_req);
TAILQ_INIT(&pd->pd_waitq_resp);
cv_init(&pd->pd_waitq_req_cv, "pudreq");
cv_init(&pd->pd_draincv, "pudrain");
mutex_enter(&pud_mtx);
LIST_INSERT_HEAD(&pudlist, pd, pd_entries);
mutex_exit(&pud_mtx);
return 0;
}
void
pudattach()
{
int error;
if ((error = putter_register(pud_config, PUTTER_MINOR_PUD)) != 0) {
printf("pudattach: can't register to putter: %d\n", error);
return;
}
mutex_init(&pud_mtx, MUTEX_DEFAULT, IPL_NONE);
}