[PATCH v3 0/4] devres: Provide krealloc_array

[PATCH v3 0/4] devres: Provide krealloc_array

[James Clark]

Changes since v2:
 
 * Remove change in qcom_geni_serial.c in the last commmit and replace
   it with a comment instead
 * Whitespace fix

Changes since v1:

 * Style fix

-----------------------

Hi,

I had a use for a devm realloc_array in a separate change, so I've
added one and updated all the obvious existing uses of it that I could
find. This is basically a copy paste of the one in slab.h

Applies to v6.3-rc3

Thanks
James

James Clark (4):
  devres: Provide krealloc_array
  hwmon: pmbus: Use devm_krealloc_array
  iio: adc: Use devm_krealloc_array
  serial: qcom_geni: Comment use of devm_krealloc rather than
    devm_krealloc_array

 .../driver-api/driver-model/devres.rst          |  1 +
 drivers/hwmon/pmbus/pmbus_core.c                |  6 +++---
 drivers/iio/adc/xilinx-ams.c                    |  9 +++------
 drivers/iio/adc/xilinx-xadc-core.c              | 17 +++++++----------
 drivers/tty/serial/qcom_geni_serial.c           |  5 +++++
 include/linux/device.h                          | 11 +++++++++++
 6 files changed, 30 insertions(+), 19 deletions(-)

-- 
2.34.1

[PATCH v3 1/4] devres: Provide krealloc_array

[James Clark]

There is no krealloc_array equivalent in devres. Users would have to
do their own multiplication overflow check so provide one.

Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: James Clark <james.clark@arm.com>
---
 Documentation/driver-api/driver-model/devres.rst |  1 +
 include/linux/device.h                           | 11 +++++++++++
 2 files changed, 12 insertions(+)

diff --git a/Documentation/driver-api/driver-model/devres.rst b/Documentation/driver-api/driver-model/devres.rst
index 4249eb4239e0..8be086b3f829 100644
--- a/Documentation/driver-api/driver-model/devres.rst
+++ b/Documentation/driver-api/driver-model/devres.rst
@@ -364,6 +364,7 @@ MEM
   devm_kmalloc_array()
   devm_kmemdup()
   devm_krealloc()
+  devm_krealloc_array()
   devm_kstrdup()
   devm_kstrdup_const()
   devm_kvasprintf()
diff --git a/include/linux/device.h b/include/linux/device.h
index 1508e637bb26..4dce92e99d08 100644
--- a/include/linux/device.h
+++ b/include/linux/device.h
@@ -223,6 +223,17 @@ static inline void *devm_kcalloc(struct device *dev,
 {
 	return devm_kmalloc_array(dev, n, size, flags | __GFP_ZERO);
 }
+static inline __realloc_size(3, 4) void * __must_check
+devm_krealloc_array(struct device *dev, void *p, size_t new_n, size_t new_size, gfp_t flags)
+{
+	size_t bytes;
+
+	if (unlikely(check_mul_overflow(new_n, new_size, &bytes)))
+		return NULL;
+
+	return devm_krealloc(dev, p, bytes, flags);
+}
+
 void devm_kfree(struct device *dev, const void *p);
 char *devm_kstrdup(struct device *dev, const char *s, gfp_t gfp) __malloc;
 const char *devm_kstrdup_const(struct device *dev, const char *s, gfp_t gfp);
-- 
2.34.1

[PATCH v3 2/4] hwmon: pmbus: Use devm_krealloc_array

[James Clark]

Now that it exists, use it instead of doing the multiplication manually.

Acked-by: Guenter Roeck <linux@roeck-us.net>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: James Clark <james.clark@arm.com>
---
 drivers/hwmon/pmbus/pmbus_core.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/drivers/hwmon/pmbus/pmbus_core.c b/drivers/hwmon/pmbus/pmbus_core.c
index 95e95783972a..e7bee25a3706 100644
--- a/drivers/hwmon/pmbus/pmbus_core.c
+++ b/drivers/hwmon/pmbus/pmbus_core.c
@@ -1190,9 +1190,9 @@ static int pmbus_add_attribute(struct pmbus_data *data, struct attribute *attr)
 {
 	if (data->num_attributes >= data->max_attributes - 1) {
 		int new_max_attrs = data->max_attributes + PMBUS_ATTR_ALLOC_SIZE;
-		void *new_attrs = devm_krealloc(data->dev, data->group.attrs,
-						new_max_attrs * sizeof(void *),
-						GFP_KERNEL);
+		void *new_attrs = devm_krealloc_array(data->dev, data->group.attrs,
+						      new_max_attrs, sizeof(void *),
+						      GFP_KERNEL);
 		if (!new_attrs)
 			return -ENOMEM;
 		data->group.attrs = new_attrs;
-- 
2.34.1

[PATCH v3 3/4] iio: adc: Use devm_krealloc_array

[James Clark]

Now that it exists, use it instead of doing the multiplication and
checking for overflow manually.

Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: James Clark <james.clark@arm.com>
---
 drivers/iio/adc/xilinx-ams.c       |  9 +++------
 drivers/iio/adc/xilinx-xadc-core.c | 17 +++++++----------
 2 files changed, 10 insertions(+), 16 deletions(-)

diff --git a/drivers/iio/adc/xilinx-ams.c b/drivers/iio/adc/xilinx-ams.c
index 34cf336b3490..f0b71a1220e0 100644
--- a/drivers/iio/adc/xilinx-ams.c
+++ b/drivers/iio/adc/xilinx-ams.c
@@ -1263,7 +1263,7 @@ static int ams_parse_firmware(struct iio_dev *indio_dev)
 	struct device *dev = indio_dev->dev.parent;
 	struct fwnode_handle *child = NULL;
 	struct fwnode_handle *fwnode = dev_fwnode(dev);
-	size_t ams_size, dev_size;
+	size_t ams_size;
 	int ret, ch_cnt = 0, i, rising_off, falling_off;
 	unsigned int num_channels = 0;
 
@@ -1320,11 +1320,8 @@ static int ams_parse_firmware(struct iio_dev *indio_dev)
 		}
 	}
 
-	dev_size = array_size(sizeof(*dev_channels), num_channels);
-	if (dev_size == SIZE_MAX)
-		return -ENOMEM;
-
-	dev_channels = devm_krealloc(dev, ams_channels, dev_size, GFP_KERNEL);
+	dev_channels = devm_krealloc_array(dev, ams_channels, num_channels,
+					   sizeof(*dev_channels), GFP_KERNEL);
 	if (!dev_channels)
 		return -ENOMEM;
 
diff --git a/drivers/iio/adc/xilinx-xadc-core.c b/drivers/iio/adc/xilinx-xadc-core.c
index 292f2892d223..dba73300f894 100644
--- a/drivers/iio/adc/xilinx-xadc-core.c
+++ b/drivers/iio/adc/xilinx-xadc-core.c
@@ -613,20 +613,17 @@ static int xadc_update_scan_mode(struct iio_dev *indio_dev,
 	const unsigned long *mask)
 {
 	struct xadc *xadc = iio_priv(indio_dev);
-	size_t new_size, n;
+	size_t n;
 	void *data;
 
 	n = bitmap_weight(mask, indio_dev->masklength);
 
-	if (check_mul_overflow(n, sizeof(*xadc->data), &new_size))
-		return -ENOMEM;
-
-	data = devm_krealloc(indio_dev->dev.parent, xadc->data,
-			     new_size, GFP_KERNEL);
+	data = devm_krealloc_array(indio_dev->dev.parent, xadc->data,
+				   n, sizeof(*xadc->data), GFP_KERNEL);
 	if (!data)
 		return -ENOMEM;
 
-	memset(data, 0, new_size);
+	memset(data, 0, n * sizeof(*xadc->data));
 	xadc->data = data;
 
 	return 0;
@@ -1281,9 +1278,9 @@ static int xadc_parse_dt(struct iio_dev *indio_dev, unsigned int *conf, int irq)
 	}
 
 	indio_dev->num_channels = num_channels;
-	indio_dev->channels = devm_krealloc(dev, channels,
-					    sizeof(*channels) * num_channels,
-					    GFP_KERNEL);
+	indio_dev->channels = devm_krealloc_array(dev, channels,
+						  num_channels, sizeof(*channels),
+						  GFP_KERNEL);
 	/* If we can't resize the channels array, just use the original */
 	if (!indio_dev->channels)
 		indio_dev->channels = channels;
-- 
2.34.1

[PATCH v3 4/4] serial: qcom_geni: Comment use of devm_krealloc rather than devm_krealloc_array

[James Clark]

Now that devm_krealloc_array is available, add a comment justifying not
changing this occurrence to avoid any future auto fixups.

Link: https://lore.kernel.org/all/20230318173402.20a4f60d@jic23-huawei/
Signed-off-by: James Clark <james.clark@arm.com>
---
 drivers/tty/serial/qcom_geni_serial.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/drivers/tty/serial/qcom_geni_serial.c b/drivers/tty/serial/qcom_geni_serial.c
index 28fbc927a546..8ae1fb7c2636 100644
--- a/drivers/tty/serial/qcom_geni_serial.c
+++ b/drivers/tty/serial/qcom_geni_serial.c
@@ -1055,6 +1055,11 @@ static int setup_fifos(struct qcom_geni_serial_port *port)
 		(port->tx_fifo_depth * port->tx_fifo_width) / BITS_PER_BYTE;
 
 	if (port->rx_buf && (old_rx_fifo_depth != port->rx_fifo_depth) && port->rx_fifo_depth) {
+		/*
+		 * Use krealloc rather than krealloc_array because rx_buf is
+		 * accessed as 1 byte entries as well as 4 byte entries so it's
+		 * not necessarily an array.
+		 */
 		port->rx_buf = devm_krealloc(uport->dev, port->rx_buf,
 					     port->rx_fifo_depth * sizeof(u32),
 					     GFP_KERNEL);
-- 
2.34.1

Re: [PATCH v3 4/4] serial: qcom_geni: Comment use of devm_krealloc rather than devm_krealloc_array

[Jonathan Cameron]

On Mon, 20 Mar 2023 14:57:09 +0000
James Clark <james.clark@arm.com> wrote:

> Now that devm_krealloc_array is available, add a comment justifying not
> changing this occurrence to avoid any future auto fixups.
> 
> Link: https://lore.kernel.org/all/20230318173402.20a4f60d@jic23-huawei/
> Signed-off-by: James Clark <james.clark@arm.com>
LGTM

Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

> ---
>  drivers/tty/serial/qcom_geni_serial.c | 5 +++++
>  1 file changed, 5 insertions(+)
> 
> diff --git a/drivers/tty/serial/qcom_geni_serial.c b/drivers/tty/serial/qcom_geni_serial.c
> index 28fbc927a546..8ae1fb7c2636 100644
> --- a/drivers/tty/serial/qcom_geni_serial.c
> +++ b/drivers/tty/serial/qcom_geni_serial.c
> @@ -1055,6 +1055,11 @@ static int setup_fifos(struct qcom_geni_serial_port *port)
>  		(port->tx_fifo_depth * port->tx_fifo_width) / BITS_PER_BYTE;
>  
>  	if (port->rx_buf && (old_rx_fifo_depth != port->rx_fifo_depth) && port->rx_fifo_depth) {
> +		/*
> +		 * Use krealloc rather than krealloc_array because rx_buf is
> +		 * accessed as 1 byte entries as well as 4 byte entries so it's
> +		 * not necessarily an array.
> +		 */
>  		port->rx_buf = devm_krealloc(uport->dev, port->rx_buf,
>  					     port->rx_fifo_depth * sizeof(u32),
>  					     GFP_KERNEL);

Re: [PATCH v3 0/4] devres: Provide krealloc_array

[James Clark]

On 20/03/2023 14:57, James Clark wrote:
> Changes since v2:
>  
>  * Remove change in qcom_geni_serial.c in the last commmit and replace
>    it with a comment instead
>  * Whitespace fix
> 
> Changes since v1:
> 
>  * Style fix
> 
> -----------------------
> 
> Hi,
> 
> I had a use for a devm realloc_array in a separate change, so I've
> added one and updated all the obvious existing uses of it that I could
> find. This is basically a copy paste of the one in slab.h
> 
> Applies to v6.3-rc3
> 
> Thanks
> James
> 
> James Clark (4):
>   devres: Provide krealloc_array
>   hwmon: pmbus: Use devm_krealloc_array
>   iio: adc: Use devm_krealloc_array
>   serial: qcom_geni: Comment use of devm_krealloc rather than
>     devm_krealloc_array
> 
>  .../driver-api/driver-model/devres.rst          |  1 +
>  drivers/hwmon/pmbus/pmbus_core.c                |  6 +++---
>  drivers/iio/adc/xilinx-ams.c                    |  9 +++------
>  drivers/iio/adc/xilinx-xadc-core.c              | 17 +++++++----------
>  drivers/tty/serial/qcom_geni_serial.c           |  5 +++++
>  include/linux/device.h                          | 11 +++++++++++
>  6 files changed, 30 insertions(+), 19 deletions(-)
> 

Hi Greg,

Is it possible to take this one? Or at least the first commit?

Thanks
James

Re: [PATCH v3 0/4] devres: Provide krealloc_array

[Greg Kroah-Hartman]

On Tue, Apr 25, 2023 at 01:51:31PM +0100, James Clark wrote:
> 
> 
> On 20/03/2023 14:57, James Clark wrote:
> > Changes since v2:
> >  
> >  * Remove change in qcom_geni_serial.c in the last commmit and replace
> >    it with a comment instead
> >  * Whitespace fix
> > 
> > Changes since v1:
> > 
> >  * Style fix
> > 
> > -----------------------
> > 
> > Hi,
> > 
> > I had a use for a devm realloc_array in a separate change, so I've
> > added one and updated all the obvious existing uses of it that I could
> > find. This is basically a copy paste of the one in slab.h
> > 
> > Applies to v6.3-rc3
> > 
> > Thanks
> > James
> > 
> > James Clark (4):
> >   devres: Provide krealloc_array
> >   hwmon: pmbus: Use devm_krealloc_array
> >   iio: adc: Use devm_krealloc_array
> >   serial: qcom_geni: Comment use of devm_krealloc rather than
> >     devm_krealloc_array
> > 
> >  .../driver-api/driver-model/devres.rst          |  1 +
> >  drivers/hwmon/pmbus/pmbus_core.c                |  6 +++---
> >  drivers/iio/adc/xilinx-ams.c                    |  9 +++------
> >  drivers/iio/adc/xilinx-xadc-core.c              | 17 +++++++----------
> >  drivers/tty/serial/qcom_geni_serial.c           |  5 +++++
> >  include/linux/device.h                          | 11 +++++++++++
> >  6 files changed, 30 insertions(+), 19 deletions(-)
> > 
> 
> Hi Greg,
> 
> Is it possible to take this one? Or at least the first commit?

It's the middle of the merge window, no one can take anything new,
sorry.  Please wait for -rc1 to come out and then resend.

thanks,

greg k-h