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freebsd/sys/netatm/atm_subr.c
Hartmut Brandt 8f52a59171 Don't remove the first mbuf in the chain if it got empty.
This removes the packet header in certain cases which later on
will give panic. Clarify what the atm_intr expects in the comment
and de-obscurify the code a little bit by replacing the portability
macros with the BSD names. The code isn't maintained externally anymore
so there's no point in keeping the extra level of obscurity.
2004-02-21 12:55:07 +00:00

621 lines
12 KiB
C

/*
* ===================================
* HARP | Host ATM Research Platform
* ===================================
*
*
* This Host ATM Research Platform ("HARP") file (the "Software") is
* made available by Network Computing Services, Inc. ("NetworkCS")
* "AS IS". NetworkCS does not provide maintenance, improvements or
* support of any kind.
*
* NETWORKCS MAKES NO WARRANTIES OR REPRESENTATIONS, EXPRESS OR IMPLIED,
* INCLUDING, BUT NOT LIMITED TO, IMPLIED WARRANTIES OF MERCHANTABILITY
* AND FITNESS FOR A PARTICULAR PURPOSE, AS TO ANY ELEMENT OF THE
* SOFTWARE OR ANY SUPPORT PROVIDED IN CONNECTION WITH THIS SOFTWARE.
* In no event shall NetworkCS be responsible for any damages, including
* but not limited to consequential damages, arising from or relating to
* any use of the Software or related support.
*
* Copyright 1994-1998 Network Computing Services, Inc.
*
* Copies of this Software may be made, however, the above copyright
* notice must be reproduced on all copies.
*/
/*
* Core ATM Services
* -----------------
*
* Miscellaneous ATM subroutines
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/errno.h>
#include <sys/malloc.h>
#include <sys/time.h>
#include <sys/kernel.h>
#include <sys/socket.h>
#include <sys/socketvar.h>
#include <sys/sysctl.h>
#include <net/if.h>
#include <net/netisr.h>
#include <netatm/port.h>
#include <netatm/queue.h>
#include <netatm/atm.h>
#include <netatm/atm_sys.h>
#include <netatm/atm_sap.h>
#include <netatm/atm_cm.h>
#include <netatm/atm_if.h>
#include <netatm/atm_stack.h>
#include <netatm/atm_pcb.h>
#include <netatm/atm_var.h>
#include <vm/uma.h>
/*
* Global variables
*/
struct atm_pif *atm_interface_head = NULL;
struct atm_ncm *atm_netconv_head = NULL;
Atm_endpoint *atm_endpoints[ENDPT_MAX+1] = {NULL};
struct stackq_entry *atm_stackq_head = NULL, *atm_stackq_tail;
struct atm_sock_stat atm_sock_stat = { { 0 } };
int atm_init = 0;
int atm_version = ATM_VERSION;
struct timeval atm_debugtime = {0, 0};
struct ifqueue atm_intrq;
uma_zone_t atm_attributes_zone;
/*
* net.harp.atm.atm_debug
*/
int atm_debug;
SYSCTL_INT(_net_harp_atm, OID_AUTO, atm_debug, CTLFLAG_RW,
&atm_debug, 0, "HARP ATM layer debugging flag");
/*
* net.harp.atm.atm_dev_print
*/
int atm_dev_print;
SYSCTL_INT(_net_harp_atm, OID_AUTO, atm_dev_print, CTLFLAG_RW,
&atm_dev_print, 0, "display ATM CPCS headers");
/*
* net.harp.atm.atm_print_data
*/
int atm_print_data;
SYSCTL_INT(_net_harp_atm, OID_AUTO, atm_print_data, CTLFLAG_RW,
&atm_print_data, 0, "display ATM CPCS payloads");
/*
* Local functions
*/
static KTimeout_ret atm_timexp(void *);
static void atm_intr(struct mbuf *);
/*
* Local variables
*/
static struct atm_time *atm_timeq = NULL;
static uma_zone_t atm_stackq_zone;
/*
* Initialize ATM kernel
*
* Performs any initialization required before things really get underway.
* Called from ATM domain initialization or from first registration function
* which gets called.
*
* Arguments:
* none
*
* Returns:
* none
*
*/
void
atm_initialize()
{
/*
* Never called from interrupts, so no locking needed
*/
if (atm_init)
return;
atm_init = 1;
atm_attributes_zone = uma_zcreate("atm attributes",
sizeof(Atm_attributes), NULL, NULL, NULL, NULL,
UMA_ALIGN_PTR, 0);
if (atm_attributes_zone == NULL)
panic("atm_initialize: unable to create attributes zone");
atm_stackq_zone = uma_zcreate("atm stackq", sizeof(struct stackq_entry),
NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, 0);
if (atm_stackq_zone == NULL)
panic("atm_initialize: unable to create stackq zone");
atm_intrq.ifq_maxlen = ATM_INTRQ_MAX;
mtx_init(&atm_intrq.ifq_mtx, "atm_inq", NULL, MTX_DEF);
netisr_register(NETISR_ATM, atm_intr, &atm_intrq, 0);
/*
* Initialize subsystems
*/
atm_sock_init();
atm_cm_init();
atm_aal5_init();
/*
* Prime the timer
*/
(void)timeout(atm_timexp, (void *)0, hz/ATM_HZ);
}
/*
* Handle timer tick expiration
*
* Decrement tick count in first block on timer queue. If there
* are blocks with expired timers, call their timeout function.
* This function is called ATM_HZ times per second.
*
* Arguments:
* arg argument passed on timeout() call
*
* Returns:
* none
*
*/
static KTimeout_ret
atm_timexp(arg)
void *arg;
{
struct atm_time *tip;
int s = splimp();
/*
* Decrement tick count
*/
if (((tip = atm_timeq) == NULL) || (--tip->ti_ticks > 0)) {
goto restart;
}
/*
* Stack queue should have been drained
*/
KASSERT(atm_stackq_head == NULL, ("atm_timexp: stack queue not empty"));
/*
* Dispatch expired timers
*/
while (((tip = atm_timeq) != NULL) && (tip->ti_ticks == 0)) {
void (*func)(struct atm_time *);
/*
* Remove expired block from queue
*/
atm_timeq = tip->ti_next;
tip->ti_flag &= ~TIF_QUEUED;
/*
* Call timeout handler (with network interrupts locked out)
*/
func = tip->ti_func;
(void) splx(s);
s = splnet();
(*func)(tip);
(void) splx(s);
s = splimp();
/*
* Drain any deferred calls
*/
STACK_DRAIN();
}
restart:
/*
* Restart the timer
*/
(void) splx(s);
(void) timeout(atm_timexp, (void *)0, hz/ATM_HZ);
return;
}
/*
* Schedule a control block timeout
*
* Place the supplied timer control block on the timer queue. The
* function (func) will be called in 't' timer ticks with the
* control block address as its only argument. There are ATM_HZ
* timer ticks per second. The ticks value stored in each block is
* a delta of the number of ticks from the previous block in the queue.
* Thus, for each tick interval, only the first block in the queue
* needs to have its tick value decremented.
*
* Arguments:
* tip pointer to timer control block
* t number of timer ticks until expiration
* func pointer to function to call at expiration
*
* Returns:
* none
*
*/
void
atm_timeout(tip, t, func)
struct atm_time *tip;
int t;
void (*func)(struct atm_time *);
{
struct atm_time *tip1, *tip2;
int s;
/*
* Check for double queueing error
*/
if (tip->ti_flag & TIF_QUEUED)
panic("atm_timeout: double queueing");
/*
* Make sure we delay at least a little bit
*/
if (t <= 0)
t = 1;
/*
* Find out where we belong on the queue
*/
s = splimp();
for (tip1 = NULL, tip2 = atm_timeq; tip2 && (tip2->ti_ticks <= t);
tip1 = tip2, tip2 = tip1->ti_next) {
t -= tip2->ti_ticks;
}
/*
* Place ourselves on queue and update timer deltas
*/
if (tip1 == NULL)
atm_timeq = tip;
else
tip1->ti_next = tip;
tip->ti_next = tip2;
if (tip2)
tip2->ti_ticks -= t;
/*
* Setup timer block
*/
tip->ti_flag |= TIF_QUEUED;
tip->ti_ticks = t;
tip->ti_func = func;
(void) splx(s);
return;
}
/*
* Cancel a timeout
*
* Remove the supplied timer control block from the timer queue.
*
* Arguments:
* tip pointer to timer control block
*
* Returns:
* 0 control block successfully dequeued
* 1 control block not on timer queue
*
*/
int
atm_untimeout(tip)
struct atm_time *tip;
{
struct atm_time *tip1, *tip2;
int s;
/*
* Is control block queued?
*/
if ((tip->ti_flag & TIF_QUEUED) == 0)
return(1);
/*
* Find control block on the queue
*/
s = splimp();
for (tip1 = NULL, tip2 = atm_timeq; tip2 && (tip2 != tip);
tip1 = tip2, tip2 = tip1->ti_next) {
}
if (tip2 == NULL) {
(void) splx(s);
return (1);
}
/*
* Remove block from queue and update timer deltas
*/
tip2 = tip->ti_next;
if (tip1 == NULL)
atm_timeq = tip2;
else
tip1->ti_next = tip2;
if (tip2)
tip2->ti_ticks += tip->ti_ticks;
/*
* Reset timer block
*/
tip->ti_flag &= ~TIF_QUEUED;
(void) splx(s);
return (0);
}
/*
* Queue a Stack Call
*
* Queues a stack call which must be deferred to the global stack queue.
* The call parameters are stored in entries which are allocated from the
* stack queue storage pool.
*
* Arguments:
* cmd stack command
* func destination function
* token destination layer's token
* cvp pointer to connection vcc
* arg1 command argument
* arg2 command argument
*
* Returns:
* 0 call queued
* errno call not queued - reason indicated
*
*/
int
atm_stack_enq(cmd, func, token, cvp, arg1, arg2)
int cmd;
void (*func)(int, void *, intptr_t, intptr_t);
void *token;
Atm_connvc *cvp;
intptr_t arg1;
intptr_t arg2;
{
struct stackq_entry *sqp;
int s = splnet();
/*
* Get a new queue entry for this call
*/
sqp = uma_zalloc(atm_stackq_zone, M_NOWAIT | M_ZERO);
if (sqp == NULL) {
(void) splx(s);
return (ENOMEM);
}
/*
* Fill in new entry
*/
sqp->sq_next = NULL;
sqp->sq_cmd = cmd;
sqp->sq_func = func;
sqp->sq_token = token;
sqp->sq_arg1 = arg1;
sqp->sq_arg2 = arg2;
sqp->sq_connvc = cvp;
/*
* Put new entry at end of queue
*/
if (atm_stackq_head == NULL)
atm_stackq_head = sqp;
else
atm_stackq_tail->sq_next = sqp;
atm_stackq_tail = sqp;
(void) splx(s);
return (0);
}
/*
* Drain the Stack Queue
*
* Dequeues and processes entries from the global stack queue.
*
* Arguments:
* none
*
* Returns:
* none
*
*/
void
atm_stack_drain()
{
struct stackq_entry *sqp, *qprev, *qnext;
int s = splnet();
int cnt;
/*
* Loop thru entire queue until queue is empty
* (but panic rather loop forever)
*/
do {
cnt = 0;
qprev = NULL;
for (sqp = atm_stackq_head; sqp; ) {
/*
* Got an eligible entry, do STACK_CALL stuff
*/
if (sqp->sq_cmd & STKCMD_UP) {
if (sqp->sq_connvc->cvc_downcnt) {
/*
* Cant process now, skip it
*/
qprev = sqp;
sqp = sqp->sq_next;
continue;
}
/*
* OK, dispatch the call
*/
sqp->sq_connvc->cvc_upcnt++;
(*sqp->sq_func)(sqp->sq_cmd,
sqp->sq_token,
sqp->sq_arg1,
sqp->sq_arg2);
sqp->sq_connvc->cvc_upcnt--;
} else {
if (sqp->sq_connvc->cvc_upcnt) {
/*
* Cant process now, skip it
*/
qprev = sqp;
sqp = sqp->sq_next;
continue;
}
/*
* OK, dispatch the call
*/
sqp->sq_connvc->cvc_downcnt++;
(*sqp->sq_func)(sqp->sq_cmd,
sqp->sq_token,
sqp->sq_arg1,
sqp->sq_arg2);
sqp->sq_connvc->cvc_downcnt--;
}
/*
* Dequeue processed entry and free it
*/
cnt++;
qnext = sqp->sq_next;
if (qprev)
qprev->sq_next = qnext;
else
atm_stackq_head = qnext;
if (qnext == NULL)
atm_stackq_tail = qprev;
uma_zfree(atm_stackq_zone, sqp);
sqp = qnext;
}
} while (cnt > 0);
/*
* Make sure entire queue was drained
*/
if (atm_stackq_head != NULL)
panic("atm_stack_drain: Queue not emptied");
(void) splx(s);
}
/*
* Process Interrupt Queue
*
* Processes entries on the ATM interrupt queue. This queue is used by
* device interface drivers in order to schedule events from the driver's
* lower (interrupt) half to the driver's stack services.
*
* The interrupt routines must store the stack processing function to call
* and a token (typically a driver/stack control block) at the front of the
* queued buffer. We assume that the function pointer and token values are
* both contained (and properly aligned) in the first buffer of the chain.
* The size of these two fields is not accounted for in the packet header
* length field. The packet header itself must be in the first mbuf.
*
* Arguments:
* none
*
* Returns:
* none
*
*/
static void
atm_intr(struct mbuf *m)
{
caddr_t cp;
atm_intr_func_t func;
void *token;
GIANT_REQUIRED;
/*
* Get function to call and token value
*/
cp = mtod(m, caddr_t);
func = *(atm_intr_func_t *)cp;
cp += sizeof(func);
token = *(void **)cp;
m->m_len -= sizeof(func) + sizeof(token);
m->m_data += sizeof(func) + sizeof(token);
/*
* Call processing function
*/
(*func)(token, m);
/*
* Drain any deferred calls
*/
STACK_DRAIN();
}
/*
* Print a pdu buffer chain
*
* Arguments:
* m pointer to pdu buffer chain
* msg pointer to message header string
*
* Returns:
* none
*
*/
void
atm_pdu_print(const KBuffer *m, const char *msg)
{
const u_char *cp;
int i;
char c = ' ';
printf("%s:", msg);
while (m) {
KB_DATASTART(m, cp, const u_char *);
printf("%cbfr=%p data=%p len=%d: ",
c, m, cp, KB_LEN(m));
c = '\t';
if (atm_print_data) {
for (i = 0; i < KB_LEN(m); i++) {
printf("%2x ", *cp++);
}
printf("<end_bfr>\n");
} else {
printf("\n");
}
m = KB_NEXT(m);
}
}