The iterated nodes are direct children of the device node, and the
`device_for_each_child_node()` macro accounts for child node
availability.
`fwnode_for_each_available_child_node()` is meant to access the child
nodes of an fwnode, and therefore not direct child nodes of the device
node.
The child nodes within mvpp2_probe are not accessed outside the lopps,
and the socped version of the macro can be used to automatically
decrement the refcount on early exits.
Use `device_for_each_child_node()` and its scoped variant to indicate
device's direct child nodes.
Signed-off-by: Javier Carrasco <javier.carrasco.cruz@gmail.com>
---
drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c | 13 ++++---------
1 file changed, 4 insertions(+), 9 deletions(-)
diff --git a/drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c b/drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c
index 9adf4301c9b1..97f1faab6f28 100644
--- a/drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c
+++ b/drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c
@@ -7417,8 +7417,6 @@ static int mvpp2_get_sram(struct platform_device *pdev,
static int mvpp2_probe(struct platform_device *pdev)
{
- struct fwnode_handle *fwnode = pdev->dev.fwnode;
- struct fwnode_handle *port_fwnode;
struct mvpp2 *priv;
struct resource *res;
void __iomem *base;
@@ -7591,7 +7589,7 @@ static int mvpp2_probe(struct platform_device *pdev)
}
/* Map DTS-active ports. Should be done before FIFO mvpp2_init */
- fwnode_for_each_available_child_node(fwnode, port_fwnode) {
+ device_for_each_child_node_scoped(&pdev->dev, port_fwnode) {
if (!fwnode_property_read_u32(port_fwnode, "port-id", &i))
priv->port_map |= BIT(i);
}
@@ -7614,7 +7612,7 @@ static int mvpp2_probe(struct platform_device *pdev)
goto err_axi_clk;
/* Initialize ports */
- fwnode_for_each_available_child_node(fwnode, port_fwnode) {
+ device_for_each_child_node_scoped(&pdev->dev, port_fwnode) {
err = mvpp2_port_probe(pdev, port_fwnode, priv);
if (err < 0)
goto err_port_probe;
@@ -7653,10 +7651,8 @@ static int mvpp2_probe(struct platform_device *pdev)
return 0;
err_port_probe:
- fwnode_handle_put(port_fwnode);
-
i = 0;
- fwnode_for_each_available_child_node(fwnode, port_fwnode) {
+ device_for_each_child_node_scoped(&pdev->dev, port_fwnode) {
if (priv->port_list[i])
mvpp2_port_remove(priv->port_list[i]);
i++;
@@ -7677,13 +7673,12 @@ static int mvpp2_probe(struct platform_device *pdev)
static void mvpp2_remove(struct platform_device *pdev)
{
struct mvpp2 *priv = platform_get_drvdata(pdev);
- struct fwnode_handle *fwnode = pdev->dev.fwnode;
int i = 0, poolnum = MVPP2_BM_POOLS_NUM;
struct fwnode_handle *port_fwnode;
mvpp2_dbgfs_cleanup(priv);
- fwnode_for_each_available_child_node(fwnode, port_fwnode) {
+ device_for_each_child_node(&pdev->dev, port_fwnode) {
if (priv->port_list[i]) {
mutex_destroy(&priv->port_list[i]->gather_stats_lock);
mvpp2_port_remove(priv->port_list[i]);
--
2.40.1On Sat, Jul 06, 2024 at 05:23:38PM +0200, Javier Carrasco wrote:
> The iterated nodes are direct children of the device node, and the
> `device_for_each_child_node()` macro accounts for child node
> availability.
>
> `fwnode_for_each_available_child_node()` is meant to access the child
> nodes of an fwnode, and therefore not direct child nodes of the device
> node.
>
> The child nodes within mvpp2_probe are not accessed outside the lopps,
"lopps" ?
> and the socped version of the macro can be used to automatically
"socped" ?
> decrement the refcount on early exits.
>
> Use `device_for_each_child_node()` and its scoped variant to indicate
> device's direct child nodes.
>
> Signed-off-by: Javier Carrasco <javier.carrasco.cruz@gmail.com>
> ---
> drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c | 13 ++++---------
> 1 file changed, 4 insertions(+), 9 deletions(-)
>
> diff --git a/drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c b/drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c
> index 9adf4301c9b1..97f1faab6f28 100644
> --- a/drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c
> +++ b/drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c
> @@ -7417,8 +7417,6 @@ static int mvpp2_get_sram(struct platform_device *pdev,
>
> static int mvpp2_probe(struct platform_device *pdev)
> {
> - struct fwnode_handle *fwnode = pdev->dev.fwnode;
> - struct fwnode_handle *port_fwnode;
> struct mvpp2 *priv;
> struct resource *res;
> void __iomem *base;
> @@ -7591,7 +7589,7 @@ static int mvpp2_probe(struct platform_device *pdev)
> }
>
> /* Map DTS-active ports. Should be done before FIFO mvpp2_init */
> - fwnode_for_each_available_child_node(fwnode, port_fwnode) {
> + device_for_each_child_node_scoped(&pdev->dev, port_fwnode) {
> if (!fwnode_property_read_u32(port_fwnode, "port-id", &i))
> priv->port_map |= BIT(i);
> }
> @@ -7614,7 +7612,7 @@ static int mvpp2_probe(struct platform_device *pdev)
> goto err_axi_clk;
>
> /* Initialize ports */
> - fwnode_for_each_available_child_node(fwnode, port_fwnode) {
> + device_for_each_child_node_scoped(&pdev->dev, port_fwnode) {
> err = mvpp2_port_probe(pdev, port_fwnode, priv);
> if (err < 0)
> goto err_port_probe;
> @@ -7653,10 +7651,8 @@ static int mvpp2_probe(struct platform_device *pdev)
> return 0;
>
> err_port_probe:
> - fwnode_handle_put(port_fwnode);
> -
> i = 0;
> - fwnode_for_each_available_child_node(fwnode, port_fwnode) {
> + device_for_each_child_node_scoped(&pdev->dev, port_fwnode) {
> if (priv->port_list[i])
> mvpp2_port_remove(priv->port_list[i]);
> i++;
> @@ -7677,13 +7673,12 @@ static int mvpp2_probe(struct platform_device *pdev)
> static void mvpp2_remove(struct platform_device *pdev)
> {
> struct mvpp2 *priv = platform_get_drvdata(pdev);
> - struct fwnode_handle *fwnode = pdev->dev.fwnode;
> int i = 0, poolnum = MVPP2_BM_POOLS_NUM;
> struct fwnode_handle *port_fwnode;
>
> mvpp2_dbgfs_cleanup(priv);
>
> - fwnode_for_each_available_child_node(fwnode, port_fwnode) {
> + device_for_each_child_node(&pdev->dev, port_fwnode) {
> if (priv->port_list[i]) {
> mutex_destroy(&priv->port_list[i]->gather_stats_lock);
> mvpp2_port_remove(priv->port_list[i]);
This loop is just silly. There is no need to iterate the child nodes.
port_fwnode is not used, and the loop boils down to:
for (i = 0; i < priv->port_count; i++) {
mutex_destroy(&priv->port_list[i]->gather_stats_lock);
mvpp2_port_remove(priv->port_list[i]);
}
Not only is walking the child nodes not necessary, but checking whether
the pointer is NULL is also unnecessary. mvpp2_port_probe() populates
the array using:
priv->port_list[priv->port_count++] = port;
and "port" can not be NULL here, so we're guaranteed that all port_list
entries for 0..priv->port_count will be non-NULL, and the driver makes
this assumption in multiple places.
In fact, I'd say that using fwnode_for_each_available_child_node() or
device_for_each_child_node() is buggy here if the availability of the
children change - it could leave ports not cleaned up.
--
RMK's Patch system: https://www.armlinux.org.uk/developer/patches/
FTTP is here! 80Mbps down 10Mbps up. Decent connectivity at last!
On 29/07/2024 10:23, Russell King (Oracle) wrote:
> On Sat, Jul 06, 2024 at 05:23:38PM +0200, Javier Carrasco wrote:
>> The iterated nodes are direct children of the device node, and the
>> `device_for_each_child_node()` macro accounts for child node
>> availability.
>>
>> `fwnode_for_each_available_child_node()` is meant to access the child
>> nodes of an fwnode, and therefore not direct child nodes of the device
>> node.
>>
>> The child nodes within mvpp2_probe are not accessed outside the lopps,
>
> "lopps" ?
>
>> and the socped version of the macro can be used to automatically
>
> "socped" ?
>
I'll fix the typos for v3.
>> decrement the refcount on early exits.
>>
>> Use `device_for_each_child_node()` and its scoped variant to indicate
>> device's direct child nodes.
>>
>> Signed-off-by: Javier Carrasco <javier.carrasco.cruz@gmail.com>
>> ---
>> drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c | 13 ++++---------
>> 1 file changed, 4 insertions(+), 9 deletions(-)
>>
>> diff --git a/drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c b/drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c
>> index 9adf4301c9b1..97f1faab6f28 100644
>> --- a/drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c
>> +++ b/drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c
>> @@ -7417,8 +7417,6 @@ static int mvpp2_get_sram(struct platform_device *pdev,
>>
>> static int mvpp2_probe(struct platform_device *pdev)
>> {
>> - struct fwnode_handle *fwnode = pdev->dev.fwnode;
>> - struct fwnode_handle *port_fwnode;
>> struct mvpp2 *priv;
>> struct resource *res;
>> void __iomem *base;
>> @@ -7591,7 +7589,7 @@ static int mvpp2_probe(struct platform_device *pdev)
>> }
>>
>> /* Map DTS-active ports. Should be done before FIFO mvpp2_init */
>> - fwnode_for_each_available_child_node(fwnode, port_fwnode) {
>> + device_for_each_child_node_scoped(&pdev->dev, port_fwnode) {
>> if (!fwnode_property_read_u32(port_fwnode, "port-id", &i))
>> priv->port_map |= BIT(i);
>> }
>> @@ -7614,7 +7612,7 @@ static int mvpp2_probe(struct platform_device *pdev)
>> goto err_axi_clk;
>>
>> /* Initialize ports */
>> - fwnode_for_each_available_child_node(fwnode, port_fwnode) {
>> + device_for_each_child_node_scoped(&pdev->dev, port_fwnode) {
>> err = mvpp2_port_probe(pdev, port_fwnode, priv);
>> if (err < 0)
>> goto err_port_probe;
>> @@ -7653,10 +7651,8 @@ static int mvpp2_probe(struct platform_device *pdev)
>> return 0;
>>
>> err_port_probe:
>> - fwnode_handle_put(port_fwnode);
>> -
>> i = 0;
>> - fwnode_for_each_available_child_node(fwnode, port_fwnode) {
>> + device_for_each_child_node_scoped(&pdev->dev, port_fwnode) {
>> if (priv->port_list[i])
>> mvpp2_port_remove(priv->port_list[i]);
>> i++;
>> @@ -7677,13 +7673,12 @@ static int mvpp2_probe(struct platform_device *pdev)
>> static void mvpp2_remove(struct platform_device *pdev)
>> {
>> struct mvpp2 *priv = platform_get_drvdata(pdev);
>> - struct fwnode_handle *fwnode = pdev->dev.fwnode;
>> int i = 0, poolnum = MVPP2_BM_POOLS_NUM;
>> struct fwnode_handle *port_fwnode;
>>
>> mvpp2_dbgfs_cleanup(priv);
>>
>> - fwnode_for_each_available_child_node(fwnode, port_fwnode) {
>> + device_for_each_child_node(&pdev->dev, port_fwnode) {
>> if (priv->port_list[i]) {
>> mutex_destroy(&priv->port_list[i]->gather_stats_lock);
>> mvpp2_port_remove(priv->port_list[i]);
>
> This loop is just silly. There is no need to iterate the child nodes.
> port_fwnode is not used, and the loop boils down to:
>
> for (i = 0; i < priv->port_count; i++) {
> mutex_destroy(&priv->port_list[i]->gather_stats_lock);
> mvpp2_port_remove(priv->port_list[i]);
> }
>
> Not only is walking the child nodes not necessary, but checking whether
> the pointer is NULL is also unnecessary. mvpp2_port_probe() populates
> the array using:
>
> priv->port_list[priv->port_count++] = port;
>
> and "port" can not be NULL here, so we're guaranteed that all port_list
> entries for 0..priv->port_count will be non-NULL, and the driver makes
> this assumption in multiple places.
>
> In fact, I'd say that using fwnode_for_each_available_child_node() or
> device_for_each_child_node() is buggy here if the availability of the
> children change - it could leave ports not cleaned up.
>
I will add your suggestions in a separate patch with the corresponding
Suggested-by: tag. In that case, and taking into account that the
pointer check is unnecessary, the loop after a goto err_port_probe will
turn into this:
err_port_probe:
for (i = 0; i < priv->port_count; i++)
mvpp2_port_remove(priv->port_list[i]);
and the loop in mvpp2_remove() will be exactly the one you suggested.
Apart from that, there is a suspicious check towards the end of the same
function:
if (is_acpi_node(port_fwnode))
return;
At the point it is called in the current implementation, port_fwnode
could have been cleaned. And after removing the loop, it is simply
uninitialized. Was that meant to be pdev->dev->fwnode?
Thanks and best regards,
Javier Carrasco
On Mon, Jul 29, 2024 at 11:23:47AM +0200, Javier Carrasco wrote:
> Apart from that, there is a suspicious check towards the end of the same
> function:
>
> if (is_acpi_node(port_fwnode))
> return;
>
> At the point it is called in the current implementation, port_fwnode
> could have been cleaned. And after removing the loop, it is simply
> uninitialized. Was that meant to be pdev->dev->fwnode?
If you're referring to the one before the clk_disable_unprepare() calls,
it's only slightly suspicious:
These clocks are setup in a:
if (dev_of_node(&pdev->dev)) {
...
}
block, so they're only setup if we have device tree. So, avoiding it
for ACPI is entirely reasonable. However, we also have software nodes
as well, so the test should be:
if (!dev_of_node(&pdev->dev))
return;
to match what the probe function is doing.
Thanks.
--
RMK's Patch system: https://www.armlinux.org.uk/developer/patches/
FTTP is here! 80Mbps down 10Mbps up. Decent connectivity at last!
On Sat, 06 Jul 2024 17:23:38 +0200 Javier Carrasco <javier.carrasco.cruz@gmail.com> wrote: > The iterated nodes are direct children of the device node, and the > `device_for_each_child_node()` macro accounts for child node > availability. > > `fwnode_for_each_available_child_node()` is meant to access the child > nodes of an fwnode, and therefore not direct child nodes of the device > node. > > The child nodes within mvpp2_probe are not accessed outside the lopps, > and the socped version of the macro can be used to automatically > decrement the refcount on early exits. > > Use `device_for_each_child_node()` and its scoped variant to indicate > device's direct child nodes. > > Signed-off-by: Javier Carrasco <javier.carrasco.cruz@gmail.com> Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
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