msm: ais: Instead of read_lock use read_lock_irqsave

Prevent deadlock between tasklet and delete_stream by stopping
irq during delete_stream.

Change-Id: I4aba47b5cab2722c352139f793b75d7c86cd49d8
CRs-fixed: 2076578
Signed-off-by: Rahul Sharma <sharah@codeaurora.org>

2 files changed, 51 insertions, 43 deletions

diff --git a/drivers/media/platform/msm/ais/msm.c b/drivers/media/platform/msm/ais/msm.c
index ccfdfba2ceee..902e05b3329b 100644
--- a/drivers/media/platform/msm/ais/msm.c
+++ b/drivers/media/platform/msm/ais/msm.c
@@ -292,6 +292,7 @@ void msm_delete_stream(unsigned int session_id, unsigned int stream_id)
 		return;
 
 	while (1) {
+		unsigned long wl_flags;
 
 		if (try_count > 5) {
 			pr_err("%s : not able to delete stream %d\n",
@@ -299,18 +300,20 @@ void msm_delete_stream(unsigned int session_id, unsigned int stream_id)
 			break;
 		}
 
-		write_lock(&session->stream_rwlock);
+		write_lock_irqsave(&session->stream_rwlock, wl_flags);
 		try_count++;
 		stream = msm_queue_find(&session->stream_q, struct msm_stream,
 			list, __msm_queue_find_stream, &stream_id);
 
 		if (!stream) {
-			write_unlock(&session->stream_rwlock);
+			write_unlock_irqrestore(&session->stream_rwlock,
+				wl_flags);
 			return;
 		}
 
 		if (msm_vb2_get_stream_state(stream) != 1) {
-			write_unlock(&session->stream_rwlock);
+			write_unlock_irqrestore(&session->stream_rwlock,
+				wl_flags);
 			continue;
 		}
 
@@ -320,7 +323,7 @@ void msm_delete_stream(unsigned int session_id, unsigned int stream_id)
 		kfree(stream);
 		stream = NULL;
 		spin_unlock_irqrestore(&(session->stream_q.lock), flags);
-		write_unlock(&session->stream_rwlock);
+		write_unlock_irqrestore(&session->stream_rwlock, wl_flags);
 		break;
 	}
 
diff --git a/drivers/media/platform/msm/ais/msm_vb2/msm_vb2.c b/drivers/media/platform/msm/ais/msm_vb2/msm_vb2.c
index 36aa3f62fbec..1cbc49c8485c 100644
--- a/drivers/media/platform/msm/ais/msm_vb2/msm_vb2.c
+++ b/drivers/media/platform/msm/ais/msm_vb2/msm_vb2.c
@@ -47,22 +47,23 @@ static int msm_vb2_buf_init(struct vb2_buffer *vb)
 	struct msm_session *session;
 	struct msm_vb2_buffer *msm_vb2_buf;
 	struct vb2_v4l2_buffer *vbuf = to_vb2_v4l2_buffer(vb);
+	unsigned long rl_flags;
 
 	session = msm_get_session_from_vb2q(vb->vb2_queue);
 	if (IS_ERR_OR_NULL(session))
 		return -EINVAL;
 
-	read_lock(&session->stream_rwlock);
+	read_lock_irqsave(&session->stream_rwlock, rl_flags);
 
 	stream = msm_get_stream_from_vb2q(vb->vb2_queue);
 	if (!stream) {
 		pr_err("%s: Couldn't find stream\n", __func__);
-		read_unlock(&session->stream_rwlock);
+		read_unlock_irqrestore(&session->stream_rwlock, rl_flags);
 		return -EINVAL;
 	}
 	msm_vb2_buf = container_of(vbuf, struct msm_vb2_buffer, vb2_v4l2_buf);
 	msm_vb2_buf->in_freeq = 0;
-	read_unlock(&session->stream_rwlock);
+	read_unlock_irqrestore(&session->stream_rwlock, rl_flags);
 	return 0;
 }
 
@@ -71,7 +72,7 @@ static void msm_vb2_buf_queue(struct vb2_buffer *vb)
 	struct msm_vb2_buffer *msm_vb2;
 	struct msm_stream *stream;
 	struct msm_session *session;
-	unsigned long flags;
+	unsigned long flags, rl_flags;
 	struct vb2_v4l2_buffer *vbuf = to_vb2_v4l2_buffer(vb);
 
 	msm_vb2 = container_of(vbuf, struct msm_vb2_buffer, vb2_v4l2_buf);
@@ -84,19 +85,19 @@ static void msm_vb2_buf_queue(struct vb2_buffer *vb)
 	if (IS_ERR_OR_NULL(session))
 		return;
 
-	read_lock(&session->stream_rwlock);
+	read_lock_irqsave(&session->stream_rwlock, rl_flags);
 
 	stream = msm_get_stream_from_vb2q(vb->vb2_queue);
 	if (!stream) {
 		pr_err("%s:%d] NULL stream", __func__, __LINE__);
-		read_unlock(&session->stream_rwlock);
+		read_unlock_irqrestore(&session->stream_rwlock, rl_flags);
 		return;
 	}
 
 	spin_lock_irqsave(&stream->stream_lock, flags);
 	list_add_tail(&msm_vb2->list, &stream->queued_list);
 	spin_unlock_irqrestore(&stream->stream_lock, flags);
-	read_unlock(&session->stream_rwlock);
+	read_unlock_irqrestore(&session->stream_rwlock, rl_flags);
 }
 
 static void msm_vb2_buf_finish(struct vb2_buffer *vb)
@@ -104,7 +105,7 @@ static void msm_vb2_buf_finish(struct vb2_buffer *vb)
 	struct msm_vb2_buffer *msm_vb2;
 	struct msm_stream *stream;
 	struct msm_session *session;
-	unsigned long flags;
+	unsigned long flags, rl_flags;
 	struct msm_vb2_buffer *msm_vb2_entry, *temp;
 	struct vb2_v4l2_buffer *vbuf = to_vb2_v4l2_buffer(vb);
 
@@ -118,12 +119,12 @@ static void msm_vb2_buf_finish(struct vb2_buffer *vb)
 	if (IS_ERR_OR_NULL(session))
 		return;
 
-	read_lock(&session->stream_rwlock);
+	read_lock_irqsave(&session->stream_rwlock, rl_flags);
 
 	stream = msm_get_stream_from_vb2q(vb->vb2_queue);
 	if (!stream) {
 		pr_err("%s:%d] NULL stream", __func__, __LINE__);
-		read_unlock(&session->stream_rwlock);
+		read_unlock_irqrestore(&session->stream_rwlock, rl_flags);
 		return;
 	}
 
@@ -136,7 +137,7 @@ static void msm_vb2_buf_finish(struct vb2_buffer *vb)
 		}
 	}
 	spin_unlock_irqrestore(&stream->stream_lock, flags);
-	read_unlock(&session->stream_rwlock);
+	read_unlock_irqrestore(&session->stream_rwlock, rl_flags);
 }
 
 static void msm_vb2_stop_stream(struct vb2_queue *q)
@@ -144,19 +145,19 @@ static void msm_vb2_stop_stream(struct vb2_queue *q)
 	struct msm_vb2_buffer *msm_vb2, *temp;
 	struct msm_stream *stream;
 	struct msm_session *session;
-	unsigned long flags;
+	unsigned long flags, rl_flags;
 	struct vb2_v4l2_buffer *vb2_v4l2_buf;
 
 	session = msm_get_session_from_vb2q(q);
 	if (IS_ERR_OR_NULL(session))
 		return;
 
-	read_lock(&session->stream_rwlock);
+	read_lock_irqsave(&session->stream_rwlock, rl_flags);
 
 	stream = msm_get_stream_from_vb2q(q);
 	if (!stream) {
 		pr_err_ratelimited("%s:%d] NULL stream", __func__, __LINE__);
-		read_unlock(&session->stream_rwlock);
+		read_unlock_irqrestore(&session->stream_rwlock, rl_flags);
 		return;
 	}
 
@@ -176,7 +177,7 @@ static void msm_vb2_stop_stream(struct vb2_queue *q)
 		msm_vb2->in_freeq = 0;
 	}
 	spin_unlock_irqrestore(&stream->stream_lock, flags);
-	read_unlock(&session->stream_rwlock);
+	read_unlock_irqrestore(&session->stream_rwlock, rl_flags);
 }
 
 int msm_vb2_get_stream_state(struct msm_stream *stream)
@@ -255,17 +256,17 @@ static struct vb2_v4l2_buffer *msm_vb2_get_buf(int session_id,
 	struct vb2_v4l2_buffer *vb2_v4l2_buf = NULL;
 	struct msm_session *session;
 	struct msm_vb2_buffer *msm_vb2 = NULL;
-	unsigned long flags;
+	unsigned long flags, rl_flags;
 
 	session = msm_get_session(session_id);
 	if (IS_ERR_OR_NULL(session))
 		return NULL;
 
-	read_lock(&session->stream_rwlock);
+	read_lock_irqsave(&session->stream_rwlock, rl_flags);
 
 	stream = msm_get_stream(session, stream_id);
 	if (IS_ERR_OR_NULL(stream)) {
-		read_unlock(&session->stream_rwlock);
+		read_unlock_irqrestore(&session->stream_rwlock, rl_flags);
 		return NULL;
 	}
 
@@ -291,7 +292,7 @@ static struct vb2_v4l2_buffer *msm_vb2_get_buf(int session_id,
 	vb2_v4l2_buf = NULL;
 end:
 	spin_unlock_irqrestore(&stream->stream_lock, flags);
-	read_unlock(&session->stream_rwlock);
+	read_unlock_irqrestore(&session->stream_rwlock, rl_flags);
 	return vb2_v4l2_buf;
 }
 
@@ -302,18 +303,18 @@ static struct vb2_v4l2_buffer *msm_vb2_get_buf_by_idx(int session_id,
 	struct vb2_v4l2_buffer *vb2_v4l2_buf = NULL;
 	struct msm_session *session;
 	struct msm_vb2_buffer *msm_vb2 = NULL;
-	unsigned long flags;
+	unsigned long flags, rl_flags;
 
 	session = msm_get_session(session_id);
 	if (IS_ERR_OR_NULL(session))
 		return NULL;
 
-	read_lock(&session->stream_rwlock);
+	read_lock_irqsave(&session->stream_rwlock, rl_flags);
 
 	stream = msm_get_stream(session, stream_id);
 
 	if (IS_ERR_OR_NULL(stream)) {
-		read_unlock(&session->stream_rwlock);
+		read_unlock_irqrestore(&session->stream_rwlock, rl_flags);
 		return NULL;
 	}
 
@@ -337,7 +338,7 @@ static struct vb2_v4l2_buffer *msm_vb2_get_buf_by_idx(int session_id,
 	vb2_v4l2_buf = NULL;
 end:
 	spin_unlock_irqrestore(&stream->stream_lock, flags);
-	read_unlock(&session->stream_rwlock);
+	read_unlock_irqrestore(&session->stream_rwlock, rl_flags);
 	return vb2_v4l2_buf;
 }
 
@@ -349,17 +350,17 @@ static int msm_vb2_put_buf(struct vb2_v4l2_buffer *vb, int session_id,
 	struct msm_vb2_buffer *msm_vb2;
 	struct vb2_v4l2_buffer *vb2_v4l2_buf = NULL;
 	int rc = 0;
-	unsigned long flags;
+	unsigned long flags, rl_flags;
 
 	session = msm_get_session(session_id);
 	if (IS_ERR_OR_NULL(session))
 		return -EINVAL;
 
-	read_lock(&session->stream_rwlock);
+	read_lock_irqsave(&session->stream_rwlock, rl_flags);
 
 	stream = msm_get_stream(session, stream_id);
 	if (IS_ERR_OR_NULL(stream)) {
-		read_unlock(&session->stream_rwlock);
+		read_unlock_irqrestore(&session->stream_rwlock, rl_flags);
 		return -EINVAL;
 	}
 
@@ -374,6 +375,8 @@ static int msm_vb2_put_buf(struct vb2_v4l2_buffer *vb, int session_id,
 			pr_err("VB buffer is INVALID vb=%pK, ses_id=%d, str_id=%d\n",
 					vb, session_id, stream_id);
 			spin_unlock_irqrestore(&stream->stream_lock, flags);
+			read_unlock_irqrestore(&session->stream_rwlock,
+				rl_flags);
 			return -EINVAL;
 		}
 		msm_vb2 =
@@ -390,7 +393,7 @@ static int msm_vb2_put_buf(struct vb2_v4l2_buffer *vb, int session_id,
 		rc = -EINVAL;
 	}
 	spin_unlock_irqrestore(&stream->stream_lock, flags);
-	read_unlock(&session->stream_rwlock);
+	read_unlock_irqrestore(&session->stream_rwlock, rl_flags);
 	return rc;
 }
 
@@ -398,7 +401,7 @@ static int msm_vb2_buf_done(struct vb2_v4l2_buffer *vb, int session_id,
 				unsigned int stream_id, uint32_t sequence,
 				struct timeval *ts, uint32_t reserved)
 {
-	unsigned long flags;
+	unsigned long flags, rl_flags;
 	struct msm_vb2_buffer *msm_vb2;
 	struct msm_stream *stream;
 	struct vb2_v4l2_buffer *vb2_v4l2_buf = NULL;
@@ -409,11 +412,11 @@ static int msm_vb2_buf_done(struct vb2_v4l2_buffer *vb, int session_id,
 	if (IS_ERR_OR_NULL(session))
 		return -EINVAL;
 
-	read_lock(&session->stream_rwlock);
+	read_lock_irqsave(&session->stream_rwlock, rl_flags);
 
 	stream = msm_get_stream(session, stream_id);
 	if (IS_ERR_OR_NULL(stream)) {
-		read_unlock(&session->stream_rwlock);
+		read_unlock_irqrestore(&session->stream_rwlock, rl_flags);
 		return -EINVAL;
 	}
 
@@ -428,6 +431,8 @@ static int msm_vb2_buf_done(struct vb2_v4l2_buffer *vb, int session_id,
 			pr_err("VB buffer is INVALID ses_id=%d, str_id=%d, vb=%pK\n",
 				    session_id, stream_id, vb);
 			spin_unlock_irqrestore(&stream->stream_lock, flags);
+			read_unlock_irqrestore(&session->stream_rwlock,
+				rl_flags);
 			return -EINVAL;
 		}
 		msm_vb2 = container_of(vb2_v4l2_buf,
@@ -448,7 +453,7 @@ static int msm_vb2_buf_done(struct vb2_v4l2_buffer *vb, int session_id,
 		rc = -EINVAL;
 	}
 	spin_unlock_irqrestore(&stream->stream_lock, flags);
-	read_unlock(&session->stream_rwlock);
+	read_unlock_irqrestore(&session->stream_rwlock, rl_flags);
 	return rc;
 }
 
@@ -459,18 +464,18 @@ long msm_vb2_return_buf_by_idx(int session_id, unsigned int stream_id,
 	struct vb2_v4l2_buffer *vb2_v4l2_buf = NULL;
 	struct msm_session *session;
 	struct msm_vb2_buffer *msm_vb2 = NULL;
-	unsigned long flags;
+	unsigned long flags, rl_flags;
 	long rc = -EINVAL;
 
 	session = msm_get_session(session_id);
 	if (IS_ERR_OR_NULL(session))
 		return rc;
 
-	read_lock(&session->stream_rwlock);
+	read_lock_irqsave(&session->stream_rwlock, rl_flags);
 
 	stream = msm_get_stream(session, stream_id);
 	if (IS_ERR_OR_NULL(stream)) {
-		read_unlock(&session->stream_rwlock);
+		read_unlock_irqrestore(&session->stream_rwlock, rl_flags);
 		return -EINVAL;
 	}
 
@@ -499,14 +504,14 @@ long msm_vb2_return_buf_by_idx(int session_id, unsigned int stream_id,
 
 end:
 	spin_unlock_irqrestore(&stream->stream_lock, flags);
-	read_unlock(&session->stream_rwlock);
+	read_unlock_irqrestore(&session->stream_rwlock, rl_flags);
 	return rc;
 }
 EXPORT_SYMBOL(msm_vb2_return_buf_by_idx);
 
 static int msm_vb2_flush_buf(int session_id, unsigned int stream_id)
 {
-	unsigned long flags;
+	unsigned long flags, rl_flags;
 	struct msm_vb2_buffer *msm_vb2;
 	struct msm_stream *stream;
 	struct vb2_v4l2_buffer *vb2_v4l2_buf = NULL;
@@ -516,11 +521,11 @@ static int msm_vb2_flush_buf(int session_id, unsigned int stream_id)
 	if (IS_ERR_OR_NULL(session))
 		return -EINVAL;
 
-	read_lock(&session->stream_rwlock);
+	read_lock_irqsave(&session->stream_rwlock, rl_flags);
 
 	stream = msm_get_stream(session, stream_id);
 	if (IS_ERR_OR_NULL(stream)) {
-		read_unlock(&session->stream_rwlock);
+		read_unlock_irqrestore(&session->stream_rwlock, rl_flags);
 		return -EINVAL;
 	}
 
@@ -532,7 +537,7 @@ static int msm_vb2_flush_buf(int session_id, unsigned int stream_id)
 		msm_vb2->in_freeq = 0;
 	}
 	spin_unlock_irqrestore(&stream->stream_lock, flags);
-	read_unlock(&session->stream_rwlock);
+	read_unlock_irqrestore(&session->stream_rwlock, rl_flags);
 	return 0;
 }