From 82838116338d89a70369ec2ac4422aaae05eb44b Mon Sep 17 00:00:00 2001
From: Mark Spencer <markster@digium.com>
Date: Fri, 10 Sep 2004 18:47:13 +0000
Subject: [PATCH] Make sure we don't try to grab the sub and channel locks
while still having the PRI lock! (bug #2392)
git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@3760 65c4cc65-6c06-0410-ace0-fbb531ad65f3
---
channels/chan_zap.c | 45 +++++++++++++++++++++++++++++++++++----------
1 file changed, 35 insertions(+), 10 deletions(-)
diff --git a/channels/chan_zap.c b/channels/chan_zap.c
index e17af276a1..0b1b1e79c0 100755
--- a/channels/chan_zap.c
+++ b/channels/chan_zap.c
@@ -631,9 +631,17 @@ static int zt_get_index(struct ast_channel *ast, struct zt_pvt *p, int nullok)
return res;
}
-static void wakeup_sub(struct zt_pvt *p, int a)
+#ifdef ZAPATA_PRI
+static void wakeup_sub(struct zt_pvt *p, int a, struct zt_pri *pri)
+#else
+static void wakeup_sub(struct zt_pvt *p, int a, void *pri)
+#endif
{
struct ast_frame null = { AST_FRAME_NULL, };
+#ifdef ZAPATA_PRI
+ if (pri)
+ ast_mutex_unlock(&pri->lock);
+#endif
for (;;) {
if (p->subs[a].owner) {
if (ast_mutex_trylock(&p->subs[a].owner->lock)) {
@@ -648,10 +656,23 @@ static void wakeup_sub(struct zt_pvt *p, int a)
} else
break;
}
+#ifdef ZAPATA_PRI
+ if (pri)
+ ast_mutex_lock(&pri->lock);
+#endif
}
-static void zap_queue_frame(struct zt_pvt *p, struct ast_frame *f)
+#ifdef ZAPATA_PRI
+static void zap_queue_frame(struct zt_pvt *p, struct ast_frame *f, struct zt_pri *pri)
+#else
+static void zap_queue_frame(struct zt_pvt *p, struct ast_frame *f, void *pri)
+#endif
{
+ /* We must unlock the PRI to avoid the possibility of a deadlock */
+#ifdef ZAPATA_PRI
+ if (pri)
+ ast_mutex_unlock(&pri->lock);
+#endif
for (;;) {
if (p->owner) {
if (ast_mutex_trylock(&p->owner->lock)) {
@@ -666,6 +687,10 @@ static void zap_queue_frame(struct zt_pvt *p, struct ast_frame *f)
} else
break;
}
+#ifdef ZAPATA_PRI
+ if (pri)
+ ast_mutex_lock(&pri->lock);
+#endif
}
static void swap_subs(struct zt_pvt *p, int a, int b)
@@ -692,8 +717,8 @@ static void swap_subs(struct zt_pvt *p, int a, int b)
p->subs[a].owner->fds[0] = p->subs[a].zfd;
if (p->subs[b].owner)
p->subs[b].owner->fds[0] = p->subs[b].zfd;
- wakeup_sub(p, a);
- wakeup_sub(p, b);
+ wakeup_sub(p, a, NULL);
+ wakeup_sub(p, b, NULL);
}
static int zt_open(char *fn)
@@ -6754,7 +6779,7 @@ static int pri_fixup_principle(struct zt_pri *pri, int principle, q931_call *c)
ast_log(LOG_DEBUG, "Assigning bearer %d/%d to CRV %d:%d\n",
pri->pvts[principle]->logicalspan, pri->pvts[principle]->prioffset,
pri->trunkgroup, crv->channel);
- wakeup_sub(crv, SUB_REAL);
+ wakeup_sub(crv, SUB_REAL, pri);
}
return principle;
}
@@ -7202,7 +7227,7 @@ static void *pri_dchannel(void *vpri)
digit = e->ring.callednum[i];
{
struct ast_frame f = { AST_FRAME_DTMF, digit, };
- zap_queue_frame(pri->pvts[chanpos], &f);
+ zap_queue_frame(pri->pvts[chanpos], &f, pri);
}
}
}
@@ -7426,7 +7451,7 @@ static void *pri_dchannel(void *vpri)
ast_mutex_lock(&pri->pvts[chanpos]->lock);
ast_log(LOG_DEBUG, "Queuing frame from PRI_EVENT_PROGRESS on channel %d/%d span %d\n",
pri->pvts[chanpos]->logicalspan, pri->pvts[chanpos]->prioffset,pri->span);
- zap_queue_frame(pri->pvts[chanpos], &f);
+ zap_queue_frame(pri->pvts[chanpos], &f, pri);
ast_mutex_unlock(&pri->pvts[chanpos]->lock);
}
}
@@ -7440,9 +7465,9 @@ static void *pri_dchannel(void *vpri)
ast_mutex_lock(&pri->pvts[chanpos]->lock);
ast_log(LOG_DEBUG, "Queuing frame from PRI_EVENT_PROCEEDING on channel %d/%d span %d\n",
pri->pvts[chanpos]->logicalspan, pri->pvts[chanpos]->prioffset,pri->span);
- zap_queue_frame(pri->pvts[chanpos], &f);
+ zap_queue_frame(pri->pvts[chanpos], &f, pri);
f.subclass = AST_CONTROL_PROCEEDING;
- zap_queue_frame(pri->pvts[chanpos], &f);
+ zap_queue_frame(pri->pvts[chanpos], &f, pri);
pri->pvts[chanpos]->proceeding=2;
ast_mutex_unlock(&pri->pvts[chanpos]->lock);
}
@@ -8489,7 +8514,7 @@ static int action_zapdialoffhook(struct mansession *s, struct message *m)
}
for (i=0; i<strlen(number); i++) {
struct ast_frame f = { AST_FRAME_DTMF, number[i] };
- zap_queue_frame(p, &f);
+ zap_queue_frame(p, &f, NULL);
}
astman_send_ack(s, m, "ZapDialOffhook");
return 0;
--
GitLab