[PATCH v2 2/2] net: fman: use devm_kzalloc() for fman and rely on devres

[ZhaoJinming]

The driver now allocates the top-level struct fman with devm_kzalloc()
so that its lifetime is bound to the device and resources are released
automatically by the driver core on probe failure or device removal.

Remove the explicit kfree(fman) from the error paths in fman_config()
and read_dts_node() to avoid double-free/use-after-free and to follow
the devm_ allocation convention.

After of_find_matching_node() consumes fm_node's reference via
of_node_put(from), the post-muram error paths no longer need to clean
up fm_node, so replace goto fman_free with direct return ERR_PTR(err).

This change complements the existing use of devm_* resources (irq,
ioremap, etc.) and simplifies the error handling paths.

Signed-off-by: ZhaoJinming <zhaojinming@xxxxxxxxxxxxx>
---
 drivers/net/ethernet/freescale/fman/fman.c | 18 +++++++-----------
 1 file changed, 7 insertions(+), 11 deletions(-)

diff --git a/drivers/net/ethernet/freescale/fman/fman.c b/drivers/net/ethernet/freescale/fman/fman.c
index 31b0081bdf91..23b938afe17a 100644
--- a/drivers/net/ethernet/freescale/fman/fman.c
+++ b/drivers/net/ethernet/freescale/fman/fman.c
@@ -1793,8 +1793,6 @@ static int fman_config(struct fman *fman)
 	kfree(fman->cfg);
 err_fm_drv:
 	kfree(fman->state);
-err_fm_state:
-	kfree(fman);
 	return -EINVAL;
 }
 
@@ -2697,7 +2695,7 @@ static struct fman *read_dts_node(struct platform_device *of_dev)
 	struct clk *clk;
 	u32 clk_rate;
 
-	fman = kzalloc_obj(*fman);
+	fman = devm_kzalloc(&of_dev->dev, sizeof(*fman), GFP_KERNEL);
 	if (!fman)
 		return ERR_PTR(-ENOMEM);
 
@@ -2759,7 +2757,7 @@ static struct fman *read_dts_node(struct platform_device *of_dev)
 		err = -EINVAL;
 		dev_err(&of_dev->dev, "%s: could not find MURAM node\n",
 			__func__);
-		goto fman_free;
+		return ERR_PTR(err);
 	}
 
 	err = of_address_to_resource(muram_node, 0,
@@ -2768,7 +2766,7 @@ static struct fman *read_dts_node(struct platform_device *of_dev)
 		of_node_put(muram_node);
 		dev_err(&of_dev->dev, "%s: of_address_to_resource() = %d\n",
 			__func__, err);
-		goto fman_free;
+		return ERR_PTR(err);
 	}
 
 	of_node_put(muram_node);
@@ -2778,7 +2776,7 @@ static struct fman *read_dts_node(struct platform_device *of_dev)
 	if (err < 0) {
 		dev_err(&of_dev->dev, "%s: irq %d allocation failed (error = %d)\n",
 			__func__, irq, err);
-		goto fman_free;
+		return ERR_PTR(err);
 	}
 
 	if (fman->dts_params.err_irq != 0) {
@@ -2788,7 +2786,7 @@ static struct fman *read_dts_node(struct platform_device *of_dev)
 		if (err < 0) {
 			dev_err(&of_dev->dev, "%s: irq %d allocation failed (error = %d)\n",
 				__func__, fman->dts_params.err_irq, err);
-			goto fman_free;
+			return ERR_PTR(err);
 		}
 	}
 
@@ -2796,7 +2794,7 @@ static struct fman *read_dts_node(struct platform_device *of_dev)
 	if (IS_ERR(base_addr)) {
 		err = PTR_ERR(base_addr);
 		dev_err(&of_dev->dev, "%s: devm_ioremap() failed\n", __func__);
-		goto fman_free;
+		return ERR_PTR(err);
 	}
 
 	fman->dts_params.base_addr = base_addr;
@@ -2808,7 +2806,7 @@ static struct fman *read_dts_node(struct platform_device *of_dev)
 	if (err) {
 		dev_err(&of_dev->dev, "%s: of_platform_populate() failed\n",
 			__func__);
-		goto fman_free;
+		return ERR_PTR(err);
 	}
 
 #ifdef CONFIG_DPAA_ERRATUM_A050385
@@ -2822,8 +2820,6 @@ static struct fman *read_dts_node(struct platform_device *of_dev)
 	of_node_put(fm_node);
 clk_put:
 	clk_put(clk);
-fman_free:
-	kfree(fman);
 	return ERR_PTR(err);
 }
 
-- 
2.20.1