[PATCH] remoteproc: imx_dsp_rproc: Improve exception handling in imx_dsp_rproc_mbox_alloc()

[Markus Elfring]

Date: Thu, 6 Apr 2023 22:00:24 +0200

The label “err_out” was used to jump to another pointer check
despite of the detail in the implementation of the function
“imx_dsp_rproc_mbox_alloc” that it was determined already
that the corresponding variable contained an error pointer
because of a failed call of the function “mbox_request_channel_byname”.

Thus perform the following adjustments:

1. Return directly after a call of the function
   “mbox_request_channel_byname” failed for the input parameter “tx”.

2. Use more appropriate labels instead.

3. Reorder jump targets at the end.

4. Omit a function call and three extra checks.


This issue was detected by using the Coccinelle software.

Signed-off-by: Markus Elfring <elfring at users.sourceforge.net>
---
 drivers/remoteproc/imx_dsp_rproc.c | 18 +++++++-----------
 1 file changed, 7 insertions(+), 11 deletions(-)

diff --git a/drivers/remoteproc/imx_dsp_rproc.c b/drivers/remoteproc/imx_dsp_rproc.c
index 21759d9e5b7b..a8ad15ef1da0 100644
--- a/drivers/remoteproc/imx_dsp_rproc.c
+++ b/drivers/remoteproc/imx_dsp_rproc.c
@@ -530,7 +530,7 @@ static int imx_dsp_rproc_mbox_alloc(struct imx_dsp_rproc *priv)
 		ret = PTR_ERR(priv->tx_ch);
 		dev_dbg(cl->dev, "failed to request tx mailbox channel: %d\n",
 			ret);
-		goto err_out;
+		return ret;
 	}

 	/* Channel for receiving message */
@@ -539,7 +539,7 @@ static int imx_dsp_rproc_mbox_alloc(struct imx_dsp_rproc *priv)
 		ret = PTR_ERR(priv->rx_ch);
 		dev_dbg(cl->dev, "failed to request rx mailbox channel: %d\n",
 			ret);
-		goto err_out;
+		goto free_channel_tx;
 	}

 	cl = &priv->cl_rxdb;
@@ -555,19 +555,15 @@ static int imx_dsp_rproc_mbox_alloc(struct imx_dsp_rproc *priv)
 		ret = PTR_ERR(priv->rxdb_ch);
 		dev_dbg(cl->dev, "failed to request mbox chan rxdb, ret %d\n",
 			ret);
-		goto err_out;
+		goto free_channel_rx;
 	}

 	return 0;

-err_out:
-	if (!IS_ERR(priv->tx_ch))
-		mbox_free_channel(priv->tx_ch);
-	if (!IS_ERR(priv->rx_ch))
-		mbox_free_channel(priv->rx_ch);
-	if (!IS_ERR(priv->rxdb_ch))
-		mbox_free_channel(priv->rxdb_ch);
-
+free_channel_rx:
+	mbox_free_channel(priv->rx_ch);
+free_channel_tx:
+	mbox_free_channel(priv->tx_ch);
 	return ret;
 }

--
2.40.0