Merge "diag: Synchronize threads to fix possible deadlock"

4 files changed, 16 insertions, 15 deletions

diff --git a/drivers/char/diag/diagchar.h b/drivers/char/diag/diagchar.h
index 409d2724042c..9d235b7abc58 100644
--- a/drivers/char/diag/diagchar.h
+++ b/drivers/char/diag/diagchar.h
@@ -1,4 +1,4 @@
-/* Copyright (c) 2008-2016, The Linux Foundation. All rights reserved.
+/* Copyright (c) 2008-2017, The Linux Foundation. All rights reserved.
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License version 2 and
@@ -514,7 +514,7 @@ struct diagchar_dev {
 	struct list_head cmd_reg_list;
 	struct mutex cmd_reg_mutex;
 	uint32_t cmd_reg_count;
-	struct mutex diagfwd_channel_mutex;
+	struct mutex diagfwd_channel_mutex[NUM_PERIPHERALS];
 	/* Sizes that reflect memory pool sizes */
 	unsigned int poolsize;
 	unsigned int poolsize_hdlc;
diff --git a/drivers/char/diag/diagchar_core.c b/drivers/char/diag/diagchar_core.c
index f8b08527d633..facdb0f40e44 100644
--- a/drivers/char/diag/diagchar_core.c
+++ b/drivers/char/diag/diagchar_core.c
@@ -3371,7 +3371,7 @@ static int diagchar_cleanup(void)
 static int __init diagchar_init(void)
 {
 	dev_t dev;
-	int error, ret;
+	int error, ret, i;
 
 	pr_debug("diagfwd initializing ..\n");
 	ret = 0;
@@ -3418,7 +3418,8 @@ static int __init diagchar_init(void)
 	mutex_init(&driver->diag_file_mutex);
 	mutex_init(&driver->delayed_rsp_mutex);
 	mutex_init(&apps_data_mutex);
-	mutex_init(&driver->diagfwd_channel_mutex);
+	for (i = 0; i < NUM_PERIPHERALS; i++)
+		mutex_init(&driver->diagfwd_channel_mutex[i]);
 	init_waitqueue_head(&driver->wait_q);
 	INIT_WORK(&(driver->diag_drain_work), diag_drain_work_fn);
 	INIT_WORK(&(driver->update_user_clients),
diff --git a/drivers/char/diag/diagfwd_peripheral.c b/drivers/char/diag/diagfwd_peripheral.c
index c1f954cdb080..3f9f7a999fdf 100644
--- a/drivers/char/diag/diagfwd_peripheral.c
+++ b/drivers/char/diag/diagfwd_peripheral.c
@@ -1,4 +1,4 @@
-/* Copyright (c) 2015-2016, The Linux Foundation. All rights reserved.
+/* Copyright (c) 2015-2017, The Linux Foundation. All rights reserved.
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License version 2 and
@@ -655,7 +655,7 @@ void diagfwd_close_transport(uint8_t transport, uint8_t peripheral)
 		return;
 	}
 
-	mutex_lock(&driver->diagfwd_channel_mutex);
+	mutex_lock(&driver->diagfwd_channel_mutex[peripheral]);
 	fwd_info = &early_init_info[transport][peripheral];
 	if (fwd_info->p_ops && fwd_info->p_ops->close)
 		fwd_info->p_ops->close(fwd_info->ctxt);
@@ -679,7 +679,7 @@ void diagfwd_close_transport(uint8_t transport, uint8_t peripheral)
 		diagfwd_late_open(dest_info);
 	diagfwd_cntl_open(dest_info);
 	init_fn(peripheral);
-	mutex_unlock(&driver->diagfwd_channel_mutex);
+	mutex_unlock(&driver->diagfwd_channel_mutex[peripheral]);
 	diagfwd_queue_read(&peripheral_info[TYPE_DATA][peripheral]);
 	diagfwd_queue_read(&peripheral_info[TYPE_CMD][peripheral]);
 }
diff --git a/drivers/char/diag/diagfwd_socket.c b/drivers/char/diag/diagfwd_socket.c
index 888949816dfe..22a60cdff7e7 100644
--- a/drivers/char/diag/diagfwd_socket.c
+++ b/drivers/char/diag/diagfwd_socket.c
@@ -1088,9 +1088,9 @@ static int diag_socket_read(void *ctxt, unsigned char *buf, int buf_len)
 				      (info->data_ready > 0) || (!info->hdl) ||
 				      (atomic_read(&info->diag_state) == 0));
 	if (err) {
-		mutex_lock(&driver->diagfwd_channel_mutex);
+		mutex_lock(&driver->diagfwd_channel_mutex[info->peripheral]);
 		diagfwd_channel_read_done(info->fwd_ctxt, buf, 0);
-		mutex_unlock(&driver->diagfwd_channel_mutex);
+		mutex_unlock(&driver->diagfwd_channel_mutex[info->peripheral]);
 		return -ERESTARTSYS;
 	}
 
@@ -1102,9 +1102,9 @@ static int diag_socket_read(void *ctxt, unsigned char *buf, int buf_len)
 		DIAG_LOG(DIAG_DEBUG_PERIPHERALS,
 			 "%s closing read thread. diag state is closed\n",
 			 info->name);
-		mutex_lock(&driver->diagfwd_channel_mutex);
+		mutex_lock(&driver->diagfwd_channel_mutex[info->peripheral]);
 		diagfwd_channel_read_done(info->fwd_ctxt, buf, 0);
-		mutex_unlock(&driver->diagfwd_channel_mutex);
+		mutex_unlock(&driver->diagfwd_channel_mutex[info->peripheral]);
 		return 0;
 	}
 
@@ -1171,10 +1171,10 @@ static int diag_socket_read(void *ctxt, unsigned char *buf, int buf_len)
 	if (total_recd > 0) {
 		DIAG_LOG(DIAG_DEBUG_PERIPHERALS, "%s read total bytes: %d\n",
 			 info->name, total_recd);
-		mutex_lock(&driver->diagfwd_channel_mutex);
+		mutex_lock(&driver->diagfwd_channel_mutex[info->peripheral]);
 		err = diagfwd_channel_read_done(info->fwd_ctxt,
 						buf, total_recd);
-		mutex_unlock(&driver->diagfwd_channel_mutex);
+		mutex_unlock(&driver->diagfwd_channel_mutex[info->peripheral]);
 		if (err)
 			goto fail;
 	} else {
@@ -1187,9 +1187,9 @@ static int diag_socket_read(void *ctxt, unsigned char *buf, int buf_len)
 	return 0;
 
 fail:
-	mutex_lock(&driver->diagfwd_channel_mutex);
+	mutex_lock(&driver->diagfwd_channel_mutex[info->peripheral]);
 	diagfwd_channel_read_done(info->fwd_ctxt, buf, 0);
-	mutex_unlock(&driver->diagfwd_channel_mutex);
+	mutex_unlock(&driver->diagfwd_channel_mutex[info->peripheral]);
 	return -EIO;
 }