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mISDN: Fix refcounting bug 

Under some configs it was still not possible to unload the driver,
because the module use count was srewed up.

Signed-off-by: Karsten Keil <keil@b1-systems.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Karsten Keil 2012-05-04 04:15:31 +00:00 committed by David S. Miller
parent 82107b73ea
commit 7ed80fe45d
1 changed files with 39 additions and 14 deletions
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53
drivers/isdn/mISDN/tei.c
View File

@ -790,18 +790,23 @@ tei_ph_data_ind(struct teimgr *tm, u_int mt, u_char *dp, int len)
static struct layer2 *
create_new_tei(struct manager *mgr, int tei, int sapi)
{
u_long opt = 0;
u_long flags;
int id;
struct layer2 *l2;
unsigned long opt = 0;
unsigned long flags;
int id;
struct layer2 *l2;
struct channel_req rq;
if (!mgr->up)
return NULL;
if ((tei >= 0) && (tei < 64))
test_and_set_bit(OPTION_L2_FIXEDTEI, &opt);
if (mgr->ch.st->dev->Dprotocols
& ((1 << ISDN_P_TE_E1) | (1 << ISDN_P_NT_E1)))
if (mgr->ch.st->dev->Dprotocols & ((1 << ISDN_P_TE_E1) |
(1 << ISDN_P_NT_E1))) {
test_and_set_bit(OPTION_L2_PMX, &opt);
rq.protocol = ISDN_P_NT_E1;
} else {
rq.protocol = ISDN_P_NT_S0;
}
l2 = create_l2(mgr->up, ISDN_P_LAPD_NT, opt, tei, sapi);
if (!l2) {
printk(KERN_WARNING "%s:no memory for layer2\n", __func__);
@ -836,6 +841,14 @@ create_new_tei(struct manager *mgr, int tei, int sapi)
l2->ch.recv = mgr->ch.recv;
l2->ch.peer = mgr->ch.peer;
l2->ch.ctrl(&l2->ch, OPEN_CHANNEL, NULL);
/* We need open here L1 for the manager as well (refcounting) */
rq.adr.dev = mgr->ch.st->dev->id;
id = mgr->ch.st->own.ctrl(&mgr->ch.st->own, OPEN_CHANNEL, &rq);
if (id < 0) {
printk(KERN_WARNING "%s: cannot open L1\n", __func__);
l2->ch.ctrl(&l2->ch, CLOSE_CHANNEL, NULL);
l2 = NULL;
}
}
return l2;
}
@ -978,10 +991,11 @@ TEIrelease(struct layer2 *l2)
static int
create_teimgr(struct manager *mgr, struct channel_req *crq)
{
struct layer2 *l2;
u_long opt = 0;
u_long flags;
int id;
struct layer2 *l2;
unsigned long opt = 0;
unsigned long flags;
int id;
struct channel_req l1rq;
if (*debug & DEBUG_L2_TEI)
printk(KERN_DEBUG "%s: %s proto(%x) adr(%d %d %d %d)\n",
@ -1016,6 +1030,7 @@ create_teimgr(struct manager *mgr, struct channel_req *crq)
if (crq->protocol == ISDN_P_LAPD_TE)
test_and_set_bit(MGR_OPT_USER, &mgr->options);
}
l1rq.adr = crq->adr;
if (mgr->ch.st->dev->Dprotocols
& ((1 << ISDN_P_TE_E1) | (1 << ISDN_P_NT_E1)))
test_and_set_bit(OPTION_L2_PMX, &opt);
@ -1055,24 +1070,34 @@ create_teimgr(struct manager *mgr, struct channel_req *crq)
l2->tm->tei_m.fsm = &teifsmu;
l2->tm->tei_m.state = ST_TEI_NOP;
l2->tm->tval = 1000; /* T201 1 sec */
if (test_bit(OPTION_L2_PMX, &opt))
l1rq.protocol = ISDN_P_TE_E1;
else
l1rq.protocol = ISDN_P_TE_S0;
} else {
l2->tm->tei_m.fsm = &teifsmn;
l2->tm->tei_m.state = ST_TEI_NOP;
l2->tm->tval = 2000; /* T202 2 sec */
if (test_bit(OPTION_L2_PMX, &opt))
l1rq.protocol = ISDN_P_NT_E1;
else
l1rq.protocol = ISDN_P_NT_S0;
}
mISDN_FsmInitTimer(&l2->tm->tei_m, &l2->tm->timer);
write_lock_irqsave(&mgr->lock, flags);
id = get_free_id(mgr);
list_add_tail(&l2->list, &mgr->layer2);
write_unlock_irqrestore(&mgr->lock, flags);
if (id < 0) {
l2->ch.ctrl(&l2->ch, CLOSE_CHANNEL, NULL);
} else {
if (id >= 0) {
l2->ch.nr = id;
l2->up->nr = id;
crq->ch = &l2->ch;
id = 0;
/* We need open here L1 for the manager as well (refcounting) */
id = mgr->ch.st->own.ctrl(&mgr->ch.st->own, OPEN_CHANNEL,
&l1rq);
}
if (id < 0)
l2->ch.ctrl(&l2->ch, CLOSE_CHANNEL, NULL);
return id;
}