minix/servers/inet/inet.c
Cristiano Giuffrida cb176df60f New RS and new signal handling for system processes.
UPDATING INFO:
20100317:
        /usr/src/etc/system.conf updated to ignore default kernel calls: copy
        it (or merge it) to /etc/system.conf.
        The hello driver (/dev/hello) added to the distribution:
        # cd /usr/src/commands/scripts && make clean install
        # cd /dev && MAKEDEV hello

KERNEL CHANGES:
- Generic signal handling support. The kernel no longer assumes PM as a signal
manager for every process. The signal manager of a given process can now be
specified in its privilege slot. When a signal has to be delivered, the kernel
performs the lookup and forwards the signal to the appropriate signal manager.
PM is the default signal manager for user processes, RS is the default signal
manager for system processes. To enable ptrace()ing for system processes, it
is sufficient to change the default signal manager to PM. This will temporarily
disable crash recovery, though.
- sys_exit() is now split into sys_exit() (i.e. exit() for system processes,
which generates a self-termination signal), and sys_clear() (i.e. used by PM
to ask the kernel to clear a process slot when a process exits).
- Added a new kernel call (i.e. sys_update()) to swap two process slots and
implement live update.

PM CHANGES:
- Posix signal handling is no longer allowed for system processes. System
signals are split into two fixed categories: termination and non-termination
signals. When a non-termination signaled is processed, PM transforms the signal
into an IPC message and delivers the message to the system process. When a
termination signal is processed, PM terminates the process.
- PM no longer assumes itself as the signal manager for system processes. It now
makes sure that every system signal goes through the kernel before being
actually processes. The kernel will then dispatch the signal to the appropriate
signal manager which may or may not be PM.

SYSLIB CHANGES:
- Simplified SEF init and LU callbacks.
- Added additional predefined SEF callbacks to debug crash recovery and
live update.
- Fixed a temporary ack in the SEF init protocol. SEF init reply is now
completely synchronous.
- Added SEF signal event type to provide a uniform interface for system
processes to deal with signals. A sef_cb_signal_handler() callback is
available for system processes to handle every received signal. A
sef_cb_signal_manager() callback is used by signal managers to process
system signals on behalf of the kernel.
- Fixed a few bugs with memory mapping and DS.

VM CHANGES:
- Page faults and memory requests coming from the kernel are now implemented
using signals.
- Added a new VM call to swap two process slots and implement live update.
- The call is used by RS at update time and in turn invokes the kernel call
sys_update().

RS CHANGES:
- RS has been reworked with a better functional decomposition.
- Better kernel call masks. com.h now defines the set of very basic kernel calls
every system service is allowed to use. This makes system.conf simpler and
easier to maintain. In addition, this guarantees a higher level of isolation
for system libraries that use one or more kernel calls internally (e.g. printf).
- RS is the default signal manager for system processes. By default, RS
intercepts every signal delivered to every system process. This makes crash
recovery possible before bringing PM and friends in the loop.
- RS now supports fast rollback when something goes wrong while initializing
the new version during a live update.
- Live update is now implemented by keeping the two versions side-by-side and
swapping the process slots when the old version is ready to update.
- Crash recovery is now implemented by keeping the two versions side-by-side
and cleaning up the old version only when the recovery process is complete.

DS CHANGES:
- Fixed a bug when the process doing ds_publish() or ds_delete() is not known
by DS.
- Fixed the completely broken support for strings. String publishing is now
implemented in the system library and simply wraps publishing of memory ranges.
Ideally, we should adopt a similar approach for other data types as well.
- Test suite fixed.

DRIVER CHANGES:
- The hello driver has been added to the Minix distribution to demonstrate basic
live update and crash recovery functionalities.
- Other drivers have been adapted to conform the new SEF interface.
2010-03-17 01:15:29 +00:00

364 lines
8.2 KiB
C

/* this file contains the interface of the network software with rest of
minix. Furthermore it contains the main loop of the network task.
Copyright 1995 Philip Homburg
The valid messages and their parameters are:
from FS:
__________________________________________________________________
| | | | | | |
| m_type | DEVICE | PROC_NR | COUNT | POSITION | ADDRESS |
|_______________|___________|_________|_______|__________|_________|
| | | | | | |
| NW_OPEN | minor dev | proc nr | mode | | |
|_______________|___________|_________|_______|__________|_________|
| | | | | | |
| NW_CLOSE | minor dev | proc nr | | | |
|_______________|___________|_________|_______|__________|_________|
| | | | | | |
| NW_IOCTL | minor dev | proc nr | | NWIO.. | address |
|_______________|___________|_________|_______|__________|_________|
| | | | | | |
| NW_READ | minor dev | proc nr | count | | address |
|_______________|___________|_________|_______|__________|_________|
| | | | | | |
| NW_WRITE | minor dev | proc nr | count | | address |
|_______________|___________|_________|_______|__________|_________|
| | | | | | |
| NW_CANCEL | minor dev | proc nr | | | |
|_______________|___________|_________|_______|__________|_________|
from DL_ETH:
_______________________________________________________________________
| | | | | | |
| m_type | DL_PORT | DL_PROC | DL_COUNT | DL_STAT | DL_TIME |
|_______________|___________|_________|__________|____________|_________|
| | | | | | |
| DL_CONF_REPLY | minor dev | proc nr | rd_count | 0 | stat | time |
|_______________|___________|_________|__________|____________|_________|
| | | | | | |
| DL_TASK_REPLY | minor dev | proc nr | rd_count | err | stat | time |
|_______________|___________|_________|__________|____________|_________|
*/
#include "inet.h"
#define _MINIX_SOURCE 1
#include <fcntl.h>
#include <unistd.h>
#include <sys/svrctl.h>
#include <minix/ds.h>
#include <minix/endpoint.h>
#include "mq.h"
#include "qp.h"
#include "proto.h"
#include "generic/type.h"
#include "generic/arp.h"
#include "generic/assert.h"
#include "generic/buf.h"
#include "generic/clock.h"
#include "generic/eth.h"
#include "generic/event.h"
#include "generic/ip.h"
#include "generic/psip.h"
#include "generic/rand256.h"
#include "generic/sr.h"
#include "generic/tcp.h"
#include "generic/udp.h"
THIS_FILE
#define RANDOM_DEV_NAME "/dev/random"
int this_proc; /* Process number of this server. */
/* Killing Solaris */
int killer_inet= 0;
#ifdef BUF_CONSISTENCY_CHECK
extern int inet_buf_debug;
#endif
#if HZ_DYNAMIC
u32_t system_hz;
#endif
_PROTOTYPE( void main, (void) );
FORWARD _PROTOTYPE( void nw_conf, (void) );
FORWARD _PROTOTYPE( void nw_init, (void) );
/* SEF functions and variables. */
FORWARD _PROTOTYPE( void sef_local_startup, (void) );
FORWARD _PROTOTYPE( int sef_cb_init_fresh, (int type, sef_init_info_t *info) );
PUBLIC void main()
{
mq_t *mq;
int r;
int source, m_type;
/* SEF local startup. */
sef_local_startup();
while (TRUE)
{
#ifdef BUF_CONSISTENCY_CHECK
if (inet_buf_debug)
{
static int buf_debug_count= 0;
if (++buf_debug_count >= inet_buf_debug)
{
buf_debug_count= 0;
if (!bf_consistency_check())
break;
}
}
#endif
if (ev_head)
{
ev_process();
continue;
}
if (clck_call_expire)
{
clck_expire_timers();
continue;
}
mq= mq_get();
if (!mq)
ip_panic(("out of messages"));
r= sef_receive(ANY, &mq->mq_mess);
if (r<0)
{
ip_panic(("unable to receive: %d", r));
}
reset_time();
source= mq->mq_mess.m_source;
m_type= mq->mq_mess.m_type;
if (source == FS_PROC_NR)
{
sr_rec(mq);
}
else if (is_notify(m_type))
{
if (_ENDPOINT_P(source) == CLOCK)
{
clck_tick(&mq->mq_mess);
mq_free(mq);
}
else if (_ENDPOINT_P(source) == PM_PROC_NR)
{
/* signaled */
/* probably SIGTERM */
mq_free(mq);
}
else
{
/* A driver is (re)started. */
eth_check_drivers(&mq->mq_mess);
mq_free(mq);
}
}
else if (m_type == DL_CONF_REPLY || m_type == DL_TASK_REPLY ||
m_type == DL_NAME_REPLY || m_type == DL_STAT_REPLY)
{
eth_rec(&mq->mq_mess);
mq_free(mq);
}
else
{
printf("inet: got bad message type 0x%x from %d\n",
mq->mq_mess.m_type, mq->mq_mess.m_source);
mq_free(mq);
}
}
ip_panic(("task is not allowed to terminate"));
}
/*===========================================================================*
* sef_local_startup *
*===========================================================================*/
PRIVATE void sef_local_startup()
{
/* Register init callbacks. */
sef_setcb_init_fresh(sef_cb_init_fresh);
sef_setcb_init_restart(sef_cb_init_fresh);
/* No live update support for now. */
/* Let SEF perform startup. */
sef_startup();
}
/*===========================================================================*
* sef_cb_init_fresh *
*===========================================================================*/
PRIVATE int sef_cb_init_fresh(int type, sef_init_info_t *info)
{
/* Initialize the inet server. */
int r;
int timerand, fd;
endpoint_t tasknr;
struct fssignon device;
u8_t randbits[32];
struct timeval tv;
char my_name[32];
#if DEBUG
printf("Starting inet...\n");
printf("%s\n", version);
#endif
#if HZ_DYNAMIC
system_hz = sys_hz();
#endif
/* Read configuration. */
nw_conf();
/* Get a random number */
timerand= 1;
fd= open(RANDOM_DEV_NAME, O_RDONLY | O_NONBLOCK);
if (fd != -1)
{
r= read(fd, randbits, sizeof(randbits));
if (r == sizeof(randbits))
timerand= 0;
else
{
printf("inet: unable to read random data from %s: %s\n",
RANDOM_DEV_NAME, r == -1 ? strerror(errno) :
r == 0 ? "EOF" : "not enough data");
}
close(fd);
}
else
{
printf("inet: unable to open random device %s: %s\n",
RANDOM_DEV_NAME, strerror(errno));
}
if (timerand)
{
printf("inet: using current time for random-number seed\n");
r= gettimeofday(&tv, NULL);
if (r == -1)
{
printf("sysutime failed: %s\n", strerror(errno));
exit(1);
}
memcpy(randbits, &tv, sizeof(tv));
}
init_rand256(randbits);
/* Our new identity as a server. */
r = sys_whoami(&tasknr, my_name, sizeof(my_name));
if (r != OK)
ip_panic(("inet: sys_whoami failed for 'inet': %d", r));
this_proc= tasknr;
/* Register the device group. */
device.dev= ip_dev;
device.style= STYLE_CLONE;
if (svrctl(FSSIGNON, (void *) &device) == -1) {
printf("inet: error %d on registering ethernet devices\n",
errno);
pause();
}
#ifdef BUF_CONSISTENCY_CHECK
inet_buf_debug= (getenv("inetbufdebug") &&
(strcmp(getenv("inetbufdebug"), "on") == 0));
inet_buf_debug= 100;
if (inet_buf_debug)
{
ip_warning(( "buffer consistency check enabled" ));
}
#endif
if (getenv("killerinet"))
{
ip_warning(( "killer inet active" ));
killer_inet= 1;
}
nw_init();
return(OK);
}
PRIVATE void nw_conf()
{
read_conf();
eth_prep();
arp_prep();
psip_prep();
ip_prep();
tcp_prep();
udp_prep();
}
PRIVATE void nw_init()
{
mq_init();
bf_init();
clck_init();
sr_init();
qp_init();
eth_init();
arp_init();
psip_init();
ip_init();
tcp_init();
udp_init();
}
PUBLIC void panic0(file, line)
char *file;
int line;
{
printf("panic at %s, %d: ", file, line);
}
PUBLIC void inet_panic()
{
printf("\ninet stacktrace: ");
util_stacktrace();
(panic)("aborted due to a panic");
for(;;);
}
#if !NDEBUG
PUBLIC void bad_assertion(file, line, what)
char *file;
int line;
char *what;
{
panic0(file, line);
printf("assertion \"%s\" failed", what);
panic();
}
PUBLIC void bad_compare(file, line, lhs, what, rhs)
char *file;
int line;
int lhs;
char *what;
int rhs;
{
panic0(file, line);
printf("compare (%d) %s (%d) failed", lhs, what, rhs);
panic();
}
#endif /* !NDEBUG */
/*
* $PchId: inet.c,v 1.23 2005/06/28 14:27:22 philip Exp $
*/