/*===========================================================================*
* dev_status *
*===========================================================================*/
void dev_status(endpoint_t drv_e)
{
/* A device sent us a notification it has something for us. Retrieve it. */
message st;
int major, get_more = 1;
endpoint_t endpt;
for (major = 0; major < NR_DEVICES; major++)
if (dmap_driver_match(drv_e, major))
break; /* 'major' is the device that sent the message */
if (major >= NR_DEVICES) /* Device endpoint not found; nothing to do */
return;
if (dev_style_asyn(dmap[major].dmap_style)) {
printf("VFS: not doing dev_status for async driver %d\n", drv_e);
return;
}
/* Continuously send DEV_STATUS messages until the device has nothing to
* say to us anymore. */
do {
int r;
st.m_type = DEV_STATUS;
r = drv_sendrec(drv_e, &st);
if (r == OK && st.REP_STATUS == ERESTART) r = EDEADEPT;
if (r != OK) {
printf("VFS: DEV_STATUS failed to %d: %d\n", drv_e, r);
if (r == EDEADSRCDST || r == EDEADEPT) return;
panic("VFS: couldn't sendrec for DEV_STATUS: %d", r);
}
switch(st.m_type) {
case DEV_REVIVE:
/* We've got results for a read/write/ioctl call to a
* synchronous character driver */
endpt = st.REP_ENDPT;
if (endpt == VFS_PROC_NR) {
endpt = find_suspended_ep(drv_e, st.REP_IO_GRANT);
if (endpt == NONE) {
printf("VFS: proc with grant %d from %d not found\n",
st.REP_IO_GRANT, st.m_source);
continue;
}
}
revive(endpt, st.REP_STATUS);
break;
case DEV_IO_READY:
/* Reply to a select request: driver is ready for I/O */
select_reply2(st.m_source, st.DEV_MINOR, st.DEV_SEL_OPS);
break;
default:
printf("VFS: unrecognized reply %d to DEV_STATUS\n",st.m_type);
/* Fall through. */
case DEV_NO_STATUS:
get_more = 0;
break;
}
} while(get_more);
}
/*===========================================================================*
* main *
*===========================================================================*/
int main(void)
{
/* This is the main program of the file system. The main loop consists of
* three major activities: getting new work, processing the work, and sending
* the reply. This loop never terminates as long as the file system runs.
*/
int transid;
struct job *job;
/* SEF local startup. */
sef_local_startup();
printf("Started VFS: %d worker thread(s)\n", NR_WTHREADS);
if (OK != (sys_getkinfo(&kinfo)))
panic("couldn't get kernel kinfo");
/* This is the main loop that gets work, processes it, and sends replies. */
while (TRUE) {
yield_all(); /* let other threads run */
self = NULL;
job = NULL;
send_work();
get_work();
transid = TRNS_GET_ID(m_in.m_type);
if (IS_VFS_FS_TRANSID(transid)) {
job = worker_getjob( (thread_t) transid - VFS_TRANSID);
if (job == NULL) {
printf("VFS: spurious message %d from endpoint %d\n",
m_in.m_type, m_in.m_source);
continue;
}
m_in.m_type = TRNS_DEL_ID(m_in.m_type);
}
if (job != NULL) {
do_fs_reply(job);
continue;
} else if (who_e == PM_PROC_NR) { /* Calls from PM */
/* Special control messages from PM */
sys_worker_start(do_pm);
continue;
} else if (is_notify(call_nr)) {
/* A task notify()ed us */
if (who_e == DS_PROC_NR)
handle_work(ds_event);
else if (fp != NULL && (fp->fp_flags & FP_SRV_PROC))
handle_work(do_dev_event);
else
sys_worker_start(do_control_msgs);
continue;
} else if (who_p < 0) { /* i.e., message comes from a task */
/* We're going to ignore this message. Tasks should
* send notify()s only.
*/
printf("VFS: ignoring message from %d (%d)\n", who_e, call_nr);
continue;
}
/* At this point we either have results from an asynchronous device
* or a new system call. In both cases a new worker thread has to be
* started and there might not be one available from the pool. This is
* not a problem (requests/replies are simply queued), except when
* they're from an FS endpoint, because these can cause a deadlock.
* handle_work() takes care of the details. */
if (IS_DRV_REPLY(call_nr)) {
/* We've got results for a device request */
struct dmap *dp;
dp = get_dmap(who_e);
if (dp != NULL) {
if (dev_style_asyn(dp->dmap_style)) {
handle_work(do_async_dev_result);
} else {
if (dp->dmap_servicing == NONE) {
printf("Got spurious dev reply from %d",
who_e);
} else {
dev_reply(dp);
}
}
continue;
}
printf("VFS: ignoring dev reply from unknown driver %d\n",
who_e);
} else {
/* Normal syscall. */
handle_work(do_work);
}
}
return(OK); /* shouldn't come here */
}