[3/5] driver core: make struct device_type.uevent() take a const *

Commit Message

Greg Kroah-Hartman Nov. 23, 2022, 12:25 p.m. UTC

The uevent() callback in struct device_type should not be modifying the
device that is passed into it, so mark it as a const * and propagate the
function signature changes out into all relevant subsystems that use
this callback.

Cc: Jens Axboe <[e-mail]>
Cc: "Rafael J. Wysocki" <[e-mail]>
Cc: Len Brown <[e-mail]>
Cc: Stefan Richter <[e-mail]>
Cc: Wolfram Sang <[e-mail]>
Cc: Alexandre Belloni <[e-mail]>
Cc: Dmitry Torokhov <[e-mail]>
Cc: Sean Young <[e-mail]>
Cc: Mauro Carvalho Chehab <[e-mail]>
Cc: Rob Herring <[e-mail]>
Cc: Frank Rowand <[e-mail]>
Cc: Maximilian Luz <[e-mail]>
Cc: Hans de Goede <[e-mail]>
Cc: Mark Gross <[e-mail]>
Cc: Vinod Koul <[e-mail]>
Cc: Bard Liao <[e-mail]>
Cc: Pierre-Louis Bossart <[e-mail]>
Cc: Sanyog Kale <[e-mail]>
Cc: Andreas Noever <[e-mail]>
Cc: Michael Jamet <[e-mail]>
Cc: Mika Westerberg <[e-mail]>
Cc: Yehezkel Bernat <[e-mail]>
Cc: Jiri Slaby <[e-mail]>
Cc: Heikki Krogerus <[e-mail]>
Cc: "Matthew Wilcox (Oracle)" <[e-mail]>
Cc: "Martin K. Petersen" <[e-mail]>
Cc: Chaitanya Kulkarni <[e-mail]>
Cc: Ming Lei <[e-mail]>
Cc: Jilin Yuan <[e-mail]>
Cc: Alan Stern <[e-mail]>
Cc: Andy Shevchenko <[e-mail]>
Cc: Sakari Ailus <[e-mail]>
Cc: Jason Gunthorpe <[e-mail]>
Cc: Thomas Gleixner <[e-mail]>
Cc: Ira Weiny <[e-mail]>
Cc: Dan Williams <[e-mail]>
Cc: Won Chung <[e-mail]>
Cc: [e-mail]
Cc: [e-mail]
Cc: [e-mail]
Cc: [e-mail]
Cc: [e-mail]
Cc: [e-mail]
Cc: [e-mail]
Cc: [e-mail]
Cc: [e-mail]
Cc: [e-mail]
Cc: [e-mail]
Cc: [e-mail]
Cc: [e-mail]
Signed-off-by: Greg Kroah-Hartman <[e-mail]>
---
 block/partitions/core.c                   |  4 ++--
 drivers/acpi/device_sysfs.c               |  8 ++++----
 drivers/acpi/internal.h                   |  2 +-
 drivers/firewire/core-device.c            |  8 ++++----
 drivers/i2c/i2c-core-base.c               |  4 ++--
 drivers/i3c/device.c                      |  4 ++--
 drivers/i3c/master.c                      |  4 ++--
 drivers/input/input.c                     | 16 ++++++++--------
 drivers/media/rc/rc-main.c                |  2 +-
 drivers/of/device.c                       |  4 ++--
 drivers/platform/surface/aggregator/bus.c |  4 ++--
 drivers/soundwire/bus_type.c              |  4 ++--
 drivers/thunderbolt/switch.c              |  4 ++--
 drivers/thunderbolt/tb.h                  |  2 +-
 drivers/thunderbolt/xdomain.c             |  6 +++---
 drivers/tty/serdev/core.c                 |  2 +-
 drivers/usb/core/message.c                |  8 ++++----
 drivers/usb/core/usb.c                    |  4 ++--
 drivers/usb/phy/phy.c                     |  6 +++---
 drivers/usb/roles/class.c                 |  3 +--
 drivers/usb/typec/class.c                 |  2 +-
 include/linux/acpi.h                      |  4 ++--
 include/linux/device.h                    |  2 +-
 include/linux/firewire.h                  |  6 +++---
 include/linux/i3c/device.h                |  4 ++--
 include/linux/of_device.h                 |  4 ++--
 include/linux/soundwire/sdw_type.h        |  2 +-
 include/linux/surface_aggregator/device.h |  2 +-
 28 files changed, 62 insertions(+), 63 deletions(-)

Comments

Rafael J. Wysocki Nov. 23, 2022, 12:38 p.m. UTC | #1

On Wed, Nov 23, 2022 at 1:25 PM Greg Kroah-Hartman
<[e-mail]> wrote:
>
> The uevent() callback in struct device_type should not be modifying the
> device that is passed into it, so mark it as a const * and propagate the
> function signature changes out into all relevant subsystems that use
> this callback.
>
> Cc: Jens Axboe <[e-mail]>
> Cc: "Rafael J. Wysocki" <[e-mail]>
> Cc: Len Brown <[e-mail]>
> Cc: Stefan Richter <[e-mail]>
> Cc: Wolfram Sang <[e-mail]>
> Cc: Alexandre Belloni <[e-mail]>
> Cc: Dmitry Torokhov <[e-mail]>
> Cc: Sean Young <[e-mail]>
> Cc: Mauro Carvalho Chehab <[e-mail]>
> Cc: Rob Herring <[e-mail]>
> Cc: Frank Rowand <[e-mail]>
> Cc: Maximilian Luz <[e-mail]>
> Cc: Hans de Goede <[e-mail]>
> Cc: Mark Gross <[e-mail]>
> Cc: Vinod Koul <[e-mail]>
> Cc: Bard Liao <[e-mail]>
> Cc: Pierre-Louis Bossart <[e-mail]>
> Cc: Sanyog Kale <[e-mail]>
> Cc: Andreas Noever <[e-mail]>
> Cc: Michael Jamet <[e-mail]>
> Cc: Mika Westerberg <[e-mail]>
> Cc: Yehezkel Bernat <[e-mail]>
> Cc: Jiri Slaby <[e-mail]>
> Cc: Heikki Krogerus <[e-mail]>
> Cc: "Matthew Wilcox (Oracle)" <[e-mail]>
> Cc: "Martin K. Petersen" <[e-mail]>
> Cc: Chaitanya Kulkarni <[e-mail]>
> Cc: Ming Lei <[e-mail]>
> Cc: Jilin Yuan <[e-mail]>
> Cc: Alan Stern <[e-mail]>
> Cc: Andy Shevchenko <[e-mail]>
> Cc: Sakari Ailus <[e-mail]>
> Cc: Jason Gunthorpe <[e-mail]>
> Cc: Thomas Gleixner <[e-mail]>
> Cc: Ira Weiny <[e-mail]>
> Cc: Dan Williams <[e-mail]>
> Cc: Won Chung <[e-mail]>
> Cc: [e-mail]
> Cc: [e-mail]
> Cc: [e-mail]
> Cc: [e-mail]
> Cc: [e-mail]
> Cc: [e-mail]
> Cc: [e-mail]
> Cc: [e-mail]
> Cc: [e-mail]
> Cc: [e-mail]
> Cc: [e-mail]
> Cc: [e-mail]
> Cc: [e-mail]
> Signed-off-by: Greg Kroah-Hartman <[e-mail]>

Acked-by: Rafael J. Wysocki <[e-mail]>

(which my ACPI maintainer hat on).

Thanks!

> ---
>  block/partitions/core.c                   |  4 ++--
>  drivers/acpi/device_sysfs.c               |  8 ++++----
>  drivers/acpi/internal.h                   |  2 +-
>  drivers/firewire/core-device.c            |  8 ++++----
>  drivers/i2c/i2c-core-base.c               |  4 ++--
>  drivers/i3c/device.c                      |  4 ++--
>  drivers/i3c/master.c                      |  4 ++--
>  drivers/input/input.c                     | 16 ++++++++--------
>  drivers/media/rc/rc-main.c                |  2 +-
>  drivers/of/device.c                       |  4 ++--
>  drivers/platform/surface/aggregator/bus.c |  4 ++--
>  drivers/soundwire/bus_type.c              |  4 ++--
>  drivers/thunderbolt/switch.c              |  4 ++--
>  drivers/thunderbolt/tb.h                  |  2 +-
>  drivers/thunderbolt/xdomain.c             |  6 +++---
>  drivers/tty/serdev/core.c                 |  2 +-
>  drivers/usb/core/message.c                |  8 ++++----
>  drivers/usb/core/usb.c                    |  4 ++--
>  drivers/usb/phy/phy.c                     |  6 +++---
>  drivers/usb/roles/class.c                 |  3 +--
>  drivers/usb/typec/class.c                 |  2 +-
>  include/linux/acpi.h                      |  4 ++--
>  include/linux/device.h                    |  2 +-
>  include/linux/firewire.h                  |  6 +++---
>  include/linux/i3c/device.h                |  4 ++--
>  include/linux/of_device.h                 |  4 ++--
>  include/linux/soundwire/sdw_type.h        |  2 +-
>  include/linux/surface_aggregator/device.h |  2 +-
>  28 files changed, 62 insertions(+), 63 deletions(-)
>
> diff --git a/block/partitions/core.c b/block/partitions/core.c
> index b8112f52d388..7b8ef6296abd 100644
> --- a/block/partitions/core.c
> +++ b/block/partitions/core.c
> @@ -254,9 +254,9 @@ static void part_release(struct device *dev)
>         iput(dev_to_bdev(dev)->bd_inode);
>  }
>
> -static int part_uevent(struct device *dev, struct kobj_uevent_env *env)
> +static int part_uevent(const struct device *dev, struct kobj_uevent_env *env)
>  {
> -       struct block_device *part = dev_to_bdev(dev);
> +       const struct block_device *part = dev_to_bdev(dev);
>
>         add_uevent_var(env, "PARTN=%u", part->bd_partno);
>         if (part->bd_meta_info && part->bd_meta_info->volname[0])
> diff --git a/drivers/acpi/device_sysfs.c b/drivers/acpi/device_sysfs.c
> index 120873dad2cc..daff2c0c5c52 100644
> --- a/drivers/acpi/device_sysfs.c
> +++ b/drivers/acpi/device_sysfs.c
> @@ -133,7 +133,7 @@ static void acpi_hide_nondev_subnodes(struct acpi_device_data *data)
>   *         -EINVAL: output error
>   *         -ENOMEM: output is truncated
>   */
> -static int create_pnp_modalias(struct acpi_device *acpi_dev, char *modalias,
> +static int create_pnp_modalias(const struct acpi_device *acpi_dev, char *modalias,
>                                int size)
>  {
>         int len;
> @@ -191,7 +191,7 @@ static int create_pnp_modalias(struct acpi_device *acpi_dev, char *modalias,
>   * only be called for devices having ACPI_DT_NAMESPACE_HID in their list of
>   * ACPI/PNP IDs.
>   */
> -static int create_of_modalias(struct acpi_device *acpi_dev, char *modalias,
> +static int create_of_modalias(const struct acpi_device *acpi_dev, char *modalias,
>                               int size)
>  {
>         struct acpi_buffer buf = { ACPI_ALLOCATE_BUFFER };
> @@ -239,7 +239,7 @@ static int create_of_modalias(struct acpi_device *acpi_dev, char *modalias,
>         return len;
>  }
>
> -int __acpi_device_uevent_modalias(struct acpi_device *adev,
> +int __acpi_device_uevent_modalias(const struct acpi_device *adev,
>                                   struct kobj_uevent_env *env)
>  {
>         int len;
> @@ -277,7 +277,7 @@ int __acpi_device_uevent_modalias(struct acpi_device *adev,
>   * Because other buses do not support ACPI HIDs & CIDs, e.g. for a device with
>   * hid:IBM0001 and cid:ACPI0001 you get: "acpi:IBM0001:ACPI0001".
>   */
> -int acpi_device_uevent_modalias(struct device *dev, struct kobj_uevent_env *env)
> +int acpi_device_uevent_modalias(const struct device *dev, struct kobj_uevent_env *env)
>  {
>         return __acpi_device_uevent_modalias(acpi_companion_match(dev), env);
>  }
> diff --git a/drivers/acpi/internal.h b/drivers/acpi/internal.h
> index 219c02df9a08..d422884eb3d0 100644
> --- a/drivers/acpi/internal.h
> +++ b/drivers/acpi/internal.h
> @@ -120,7 +120,7 @@ int acpi_bus_register_early_device(int type);
>                       Device Matching and Notification
>     -------------------------------------------------------------------------- */
>  struct acpi_device *acpi_companion_match(const struct device *dev);
> -int __acpi_device_uevent_modalias(struct acpi_device *adev,
> +int __acpi_device_uevent_modalias(const struct acpi_device *adev,
>                                   struct kobj_uevent_env *env);
>
>  /* --------------------------------------------------------------------------
> diff --git a/drivers/firewire/core-device.c b/drivers/firewire/core-device.c
> index adddd8c45d0c..aa597cda0d88 100644
> --- a/drivers/firewire/core-device.c
> +++ b/drivers/firewire/core-device.c
> @@ -133,7 +133,7 @@ static void get_ids(const u32 *directory, int *id)
>         }
>  }
>
> -static void get_modalias_ids(struct fw_unit *unit, int *id)
> +static void get_modalias_ids(const struct fw_unit *unit, int *id)
>  {
>         get_ids(&fw_parent_device(unit)->config_rom[5], id);
>         get_ids(unit->directory, id);
> @@ -195,7 +195,7 @@ static void fw_unit_remove(struct device *dev)
>         driver->remove(fw_unit(dev));
>  }
>
> -static int get_modalias(struct fw_unit *unit, char *buffer, size_t buffer_size)
> +static int get_modalias(const struct fw_unit *unit, char *buffer, size_t buffer_size)
>  {
>         int id[] = {0, 0, 0, 0};
>
> @@ -206,9 +206,9 @@ static int get_modalias(struct fw_unit *unit, char *buffer, size_t buffer_size)
>                         id[0], id[1], id[2], id[3]);
>  }
>
> -static int fw_unit_uevent(struct device *dev, struct kobj_uevent_env *env)
> +static int fw_unit_uevent(const struct device *dev, struct kobj_uevent_env *env)
>  {
> -       struct fw_unit *unit = fw_unit(dev);
> +       const struct fw_unit *unit = fw_unit(dev);
>         char modalias[64];
>
>         get_modalias(unit, modalias, sizeof(modalias));
> diff --git a/drivers/i2c/i2c-core-base.c b/drivers/i2c/i2c-core-base.c
> index b4edf10e8fd0..fb16e33e52c6 100644
> --- a/drivers/i2c/i2c-core-base.c
> +++ b/drivers/i2c/i2c-core-base.c
> @@ -136,9 +136,9 @@ static int i2c_device_match(struct device *dev, struct device_driver *drv)
>         return 0;
>  }
>
> -static int i2c_device_uevent(struct device *dev, struct kobj_uevent_env *env)
> +static int i2c_device_uevent(const struct device *dev, struct kobj_uevent_env *env)
>  {
> -       struct i2c_client *client = to_i2c_client(dev);
> +       const struct i2c_client *client = to_i2c_client(dev);
>         int rc;
>
>         rc = of_device_uevent_modalias(dev, env);
> diff --git a/drivers/i3c/device.c b/drivers/i3c/device.c
> index e92d3e9a52bd..05f8ab762e34 100644
> --- a/drivers/i3c/device.c
> +++ b/drivers/i3c/device.c
> @@ -58,7 +58,7 @@ EXPORT_SYMBOL_GPL(i3c_device_do_priv_xfers);
>   *
>   * Retrieve I3C dev info.
>   */
> -void i3c_device_get_info(struct i3c_device *dev,
> +void i3c_device_get_info(const struct i3c_device *dev,
>                          struct i3c_device_info *info)
>  {
>         if (!info)
> @@ -194,7 +194,7 @@ EXPORT_SYMBOL_GPL(i3cdev_to_dev);
>   *
>   * Return: a pointer to an I3C device object.
>   */
> -struct i3c_device *dev_to_i3cdev(struct device *dev)
> +struct i3c_device *dev_to_i3cdev(const struct device *dev)
>  {
>         return container_of(dev, struct i3c_device, dev);
>  }
> diff --git a/drivers/i3c/master.c b/drivers/i3c/master.c
> index 351c81a929a6..bf1a2b2f34c4 100644
> --- a/drivers/i3c/master.c
> +++ b/drivers/i3c/master.c
> @@ -273,9 +273,9 @@ static struct attribute *i3c_device_attrs[] = {
>  };
>  ATTRIBUTE_GROUPS(i3c_device);
>
> -static int i3c_device_uevent(struct device *dev, struct kobj_uevent_env *env)
> +static int i3c_device_uevent(const struct device *dev, struct kobj_uevent_env *env)
>  {
> -       struct i3c_device *i3cdev = dev_to_i3cdev(dev);
> +       const struct i3c_device *i3cdev = dev_to_i3cdev(dev);
>         struct i3c_device_info devinfo;
>         u16 manuf, part, ext;
>
> diff --git a/drivers/input/input.c b/drivers/input/input.c
> index 50597165dc54..a612afffa196 100644
> --- a/drivers/input/input.c
> +++ b/drivers/input/input.c
> @@ -1371,7 +1371,7 @@ INPUT_DEV_STRING_ATTR_SHOW(phys);
>  INPUT_DEV_STRING_ATTR_SHOW(uniq);
>
>  static int input_print_modalias_bits(char *buf, int size,
> -                                    char name, unsigned long *bm,
> +                                    char name, const unsigned long *bm,
>                                      unsigned int min_bit, unsigned int max_bit)
>  {
>         int len = 0, i;
> @@ -1383,7 +1383,7 @@ static int input_print_modalias_bits(char *buf, int size,
>         return len;
>  }
>
> -static int input_print_modalias(char *buf, int size, struct input_dev *id,
> +static int input_print_modalias(char *buf, int size, const struct input_dev *id,
>                                 int add_cr)
>  {
>         int len;
> @@ -1431,7 +1431,7 @@ static ssize_t input_dev_show_modalias(struct device *dev,
>  }
>  static DEVICE_ATTR(modalias, S_IRUGO, input_dev_show_modalias, NULL);
>
> -static int input_print_bitmap(char *buf, int buf_size, unsigned long *bitmap,
> +static int input_print_bitmap(char *buf, int buf_size, const unsigned long *bitmap,
>                               int max, int add_cr);
>
>  static ssize_t input_dev_show_properties(struct device *dev,
> @@ -1523,7 +1523,7 @@ static const struct attribute_group input_dev_id_attr_group = {
>         .attrs  = input_dev_id_attrs,
>  };
>
> -static int input_print_bitmap(char *buf, int buf_size, unsigned long *bitmap,
> +static int input_print_bitmap(char *buf, int buf_size, const unsigned long *bitmap,
>                               int max, int add_cr)
>  {
>         int i;
> @@ -1620,7 +1620,7 @@ static void input_dev_release(struct device *device)
>   * device bitfields.
>   */
>  static int input_add_uevent_bm_var(struct kobj_uevent_env *env,
> -                                  const char *name, unsigned long *bitmap, int max)
> +                                  const char *name, const unsigned long *bitmap, int max)
>  {
>         int len;
>
> @@ -1638,7 +1638,7 @@ static int input_add_uevent_bm_var(struct kobj_uevent_env *env,
>  }
>
>  static int input_add_uevent_modalias_var(struct kobj_uevent_env *env,
> -                                        struct input_dev *dev)
> +                                        const struct input_dev *dev)
>  {
>         int len;
>
> @@ -1676,9 +1676,9 @@ static int input_add_uevent_modalias_var(struct kobj_uevent_env *env,
>                         return err;                                     \
>         } while (0)
>
> -static int input_dev_uevent(struct device *device, struct kobj_uevent_env *env)
> +static int input_dev_uevent(const struct device *device, struct kobj_uevent_env *env)
>  {
> -       struct input_dev *dev = to_input_dev(device);
> +       const struct input_dev *dev = to_input_dev(device);
>
>         INPUT_ADD_HOTPLUG_VAR("PRODUCT=%x/%x/%x/%x",
>                                 dev->id.bustype, dev->id.vendor,
> diff --git a/drivers/media/rc/rc-main.c b/drivers/media/rc/rc-main.c
> index 527d9324742b..6bdad6341844 100644
> --- a/drivers/media/rc/rc-main.c
> +++ b/drivers/media/rc/rc-main.c
> @@ -1614,7 +1614,7 @@ static void rc_dev_release(struct device *device)
>         kfree(dev);
>  }
>
> -static int rc_dev_uevent(struct device *device, struct kobj_uevent_env *env)
> +static int rc_dev_uevent(const struct device *device, struct kobj_uevent_env *env)
>  {
>         struct rc_dev *dev = to_rc_dev(device);
>         int ret = 0;
> diff --git a/drivers/of/device.c b/drivers/of/device.c
> index c674a13c3055..dda51b7ce597 100644
> --- a/drivers/of/device.c
> +++ b/drivers/of/device.c
> @@ -248,7 +248,7 @@ const void *of_device_get_match_data(const struct device *dev)
>  }
>  EXPORT_SYMBOL(of_device_get_match_data);
>
> -static ssize_t of_device_get_modalias(struct device *dev, char *str, ssize_t len)
> +static ssize_t of_device_get_modalias(const struct device *dev, char *str, ssize_t len)
>  {
>         const char *compat;
>         char *c;
> @@ -372,7 +372,7 @@ void of_device_uevent(const struct device *dev, struct kobj_uevent_env *env)
>         mutex_unlock(&of_mutex);
>  }
>
> -int of_device_uevent_modalias(struct device *dev, struct kobj_uevent_env *env)
> +int of_device_uevent_modalias(const struct device *dev, struct kobj_uevent_env *env)
>  {
>         int sl;
>
> diff --git a/drivers/platform/surface/aggregator/bus.c b/drivers/platform/surface/aggregator/bus.c
> index de539938896e..407eb55050a6 100644
> --- a/drivers/platform/surface/aggregator/bus.c
> +++ b/drivers/platform/surface/aggregator/bus.c
> @@ -35,9 +35,9 @@ static struct attribute *ssam_device_attrs[] = {
>  };
>  ATTRIBUTE_GROUPS(ssam_device);
>
> -static int ssam_device_uevent(struct device *dev, struct kobj_uevent_env *env)
> +static int ssam_device_uevent(const struct device *dev, struct kobj_uevent_env *env)
>  {
> -       struct ssam_device *sdev = to_ssam_device(dev);
> +       const struct ssam_device *sdev = to_ssam_device(dev);
>
>         return add_uevent_var(env, "MODALIAS=ssam:d%02Xc%02Xt%02Xi%02Xf%02X",
>                               sdev->uid.domain, sdev->uid.category,
> diff --git a/drivers/soundwire/bus_type.c b/drivers/soundwire/bus_type.c
> index 04b3529f8929..26c9a0a85d49 100644
> --- a/drivers/soundwire/bus_type.c
> +++ b/drivers/soundwire/bus_type.c
> @@ -58,9 +58,9 @@ int sdw_slave_modalias(const struct sdw_slave *slave, char *buf, size_t size)
>                         slave->id.sdw_version, slave->id.class_id);
>  }
>
> -int sdw_slave_uevent(struct device *dev, struct kobj_uevent_env *env)
> +int sdw_slave_uevent(const struct device *dev, struct kobj_uevent_env *env)
>  {
> -       struct sdw_slave *slave = dev_to_sdw_dev(dev);
> +       const struct sdw_slave *slave = dev_to_sdw_dev(dev);
>         char modalias[32];
>
>         sdw_slave_modalias(slave, modalias, sizeof(modalias));
> diff --git a/drivers/thunderbolt/switch.c b/drivers/thunderbolt/switch.c
> index 60da5c23ccaf..2f4ef156b210 100644
> --- a/drivers/thunderbolt/switch.c
> +++ b/drivers/thunderbolt/switch.c
> @@ -2175,9 +2175,9 @@ static void tb_switch_release(struct device *dev)
>         kfree(sw);
>  }
>
> -static int tb_switch_uevent(struct device *dev, struct kobj_uevent_env *env)
> +static int tb_switch_uevent(const struct device *dev, struct kobj_uevent_env *env)
>  {
> -       struct tb_switch *sw = tb_to_switch(dev);
> +       const struct tb_switch *sw = tb_to_switch(dev);
>         const char *type;
>
>         if (sw->config.thunderbolt_version == USB4_VERSION_1_0) {
> diff --git a/drivers/thunderbolt/tb.h b/drivers/thunderbolt/tb.h
> index f9786976f5ec..909da0a98134 100644
> --- a/drivers/thunderbolt/tb.h
> +++ b/drivers/thunderbolt/tb.h
> @@ -815,7 +815,7 @@ static inline bool tb_is_switch(const struct device *dev)
>         return dev->type == &tb_switch_type;
>  }
>
> -static inline struct tb_switch *tb_to_switch(struct device *dev)
> +static inline struct tb_switch *tb_to_switch(const struct device *dev)
>  {
>         if (tb_is_switch(dev))
>                 return container_of(dev, struct tb_switch, dev);
> diff --git a/drivers/thunderbolt/xdomain.c b/drivers/thunderbolt/xdomain.c
> index f00b2f62d8e3..aeb40a384bea 100644
> --- a/drivers/thunderbolt/xdomain.c
> +++ b/drivers/thunderbolt/xdomain.c
> @@ -881,7 +881,7 @@ static ssize_t key_show(struct device *dev, struct device_attribute *attr,
>  }
>  static DEVICE_ATTR_RO(key);
>
> -static int get_modalias(struct tb_service *svc, char *buf, size_t size)
> +static int get_modalias(const struct tb_service *svc, char *buf, size_t size)
>  {
>         return snprintf(buf, size, "tbsvc:k%sp%08Xv%08Xr%08X", svc->key,
>                         svc->prtcid, svc->prtcvers, svc->prtcrevs);
> @@ -953,9 +953,9 @@ static const struct attribute_group *tb_service_attr_groups[] = {
>         NULL,
>  };
>
> -static int tb_service_uevent(struct device *dev, struct kobj_uevent_env *env)
> +static int tb_service_uevent(const struct device *dev, struct kobj_uevent_env *env)
>  {
> -       struct tb_service *svc = container_of(dev, struct tb_service, dev);
> +       const struct tb_service *svc = container_of(dev, struct tb_service, dev);
>         char modalias[64];
>
>         get_modalias(svc, modalias, sizeof(modalias));
> diff --git a/drivers/tty/serdev/core.c b/drivers/tty/serdev/core.c
> index 0180e1e4e75d..aa80de3a8194 100644
> --- a/drivers/tty/serdev/core.c
> +++ b/drivers/tty/serdev/core.c
> @@ -42,7 +42,7 @@ static struct attribute *serdev_device_attrs[] = {
>  };
>  ATTRIBUTE_GROUPS(serdev_device);
>
> -static int serdev_device_uevent(struct device *dev, struct kobj_uevent_env *env)
> +static int serdev_device_uevent(const struct device *dev, struct kobj_uevent_env *env)
>  {
>         int rc;
>
> diff --git a/drivers/usb/core/message.c b/drivers/usb/core/message.c
> index 4d59d927ae3e..c397574a6570 100644
> --- a/drivers/usb/core/message.c
> +++ b/drivers/usb/core/message.c
> @@ -1818,11 +1818,11 @@ void usb_authorize_interface(struct usb_interface *intf)
>         }
>  }
>
> -static int usb_if_uevent(struct device *dev, struct kobj_uevent_env *env)
> +static int usb_if_uevent(const struct device *dev, struct kobj_uevent_env *env)
>  {
> -       struct usb_device *usb_dev;
> -       struct usb_interface *intf;
> -       struct usb_host_interface *alt;
> +       const struct usb_device *usb_dev;
> +       const struct usb_interface *intf;
> +       const struct usb_host_interface *alt;
>
>         intf = to_usb_interface(dev);
>         usb_dev = interface_to_usbdev(intf);
> diff --git a/drivers/usb/core/usb.c b/drivers/usb/core/usb.c
> index 11b15d7b357a..8527c06b65e6 100644
> --- a/drivers/usb/core/usb.c
> +++ b/drivers/usb/core/usb.c
> @@ -423,9 +423,9 @@ static void usb_release_dev(struct device *dev)
>         kfree(udev);
>  }
>
> -static int usb_dev_uevent(struct device *dev, struct kobj_uevent_env *env)
> +static int usb_dev_uevent(const struct device *dev, struct kobj_uevent_env *env)
>  {
> -       struct usb_device *usb_dev;
> +       const struct usb_device *usb_dev;
>
>         usb_dev = to_usb_device(dev);
>
> diff --git a/drivers/usb/phy/phy.c b/drivers/usb/phy/phy.c
> index 1b24492bb4e5..4b468bde19cf 100644
> --- a/drivers/usb/phy/phy.c
> +++ b/drivers/usb/phy/phy.c
> @@ -80,7 +80,7 @@ static struct usb_phy *__of_usb_find_phy(struct device_node *node)
>         return ERR_PTR(-EPROBE_DEFER);
>  }
>
> -static struct usb_phy *__device_to_usb_phy(struct device *dev)
> +static struct usb_phy *__device_to_usb_phy(const struct device *dev)
>  {
>         struct usb_phy *usb_phy;
>
> @@ -145,9 +145,9 @@ static void usb_phy_notify_charger_work(struct work_struct *work)
>         kobject_uevent(&usb_phy->dev->kobj, KOBJ_CHANGE);
>  }
>
> -static int usb_phy_uevent(struct device *dev, struct kobj_uevent_env *env)
> +static int usb_phy_uevent(const struct device *dev, struct kobj_uevent_env *env)
>  {
> -       struct usb_phy *usb_phy;
> +       const struct usb_phy *usb_phy;
>         char uchger_state[50] = { 0 };
>         char uchger_type[50] = { 0 };
>         unsigned long flags;
> diff --git a/drivers/usb/roles/class.c b/drivers/usb/roles/class.c
> index a3575a5a18ce..3708fb70b693 100644
> --- a/drivers/usb/roles/class.c
> +++ b/drivers/usb/roles/class.c
> @@ -271,8 +271,7 @@ static const struct attribute_group *usb_role_switch_groups[] = {
>         NULL,
>  };
>
> -static int
> -usb_role_switch_uevent(struct device *dev, struct kobj_uevent_env *env)
> +static int usb_role_switch_uevent(const struct device *dev, struct kobj_uevent_env *env)
>  {
>         int ret;
>
> diff --git a/drivers/usb/typec/class.c b/drivers/usb/typec/class.c
> index bd5e5dd70431..8e2b2077f262 100644
> --- a/drivers/usb/typec/class.c
> +++ b/drivers/usb/typec/class.c
> @@ -1718,7 +1718,7 @@ static const struct attribute_group *typec_groups[] = {
>         NULL
>  };
>
> -static int typec_uevent(struct device *dev, struct kobj_uevent_env *env)
> +static int typec_uevent(const struct device *dev, struct kobj_uevent_env *env)
>  {
>         int ret;
>
> diff --git a/include/linux/acpi.h b/include/linux/acpi.h
> index 3015235d65e3..fc956c3f8324 100644
> --- a/include/linux/acpi.h
> +++ b/include/linux/acpi.h
> @@ -722,7 +722,7 @@ const struct acpi_device_id *acpi_match_device(const struct acpi_device_id *ids,
>  const void *acpi_device_get_match_data(const struct device *dev);
>  extern bool acpi_driver_match_device(struct device *dev,
>                                      const struct device_driver *drv);
> -int acpi_device_uevent_modalias(struct device *, struct kobj_uevent_env *);
> +int acpi_device_uevent_modalias(const struct device *, struct kobj_uevent_env *);
>  int acpi_device_modalias(struct device *, char *, int);
>
>  struct platform_device *acpi_create_platform_device(struct acpi_device *,
> @@ -957,7 +957,7 @@ static inline union acpi_object *acpi_evaluate_dsm(acpi_handle handle,
>         return NULL;
>  }
>
> -static inline int acpi_device_uevent_modalias(struct device *dev,
> +static inline int acpi_device_uevent_modalias(const struct device *dev,
>                                 struct kobj_uevent_env *env)
>  {
>         return -ENODEV;
> diff --git a/include/linux/device.h b/include/linux/device.h
> index 84ae52de6746..46093bae6905 100644
> --- a/include/linux/device.h
> +++ b/include/linux/device.h
> @@ -88,7 +88,7 @@ int subsys_virtual_register(struct bus_type *subsys,
>  struct device_type {
>         const char *name;
>         const struct attribute_group **groups;
> -       int (*uevent)(struct device *dev, struct kobj_uevent_env *env);
> +       int (*uevent)(const struct device *dev, struct kobj_uevent_env *env);
>         char *(*devnode)(struct device *dev, umode_t *mode,
>                          kuid_t *uid, kgid_t *gid);
>         void (*release)(struct device *dev);
> diff --git a/include/linux/firewire.h b/include/linux/firewire.h
> index 980019053e54..4c882d57df02 100644
> --- a/include/linux/firewire.h
> +++ b/include/linux/firewire.h
> @@ -208,7 +208,7 @@ struct fw_device {
>         struct fw_attribute_group attribute_group;
>  };
>
> -static inline struct fw_device *fw_device(struct device *dev)
> +static inline struct fw_device *fw_device(const struct device *dev)
>  {
>         return container_of(dev, struct fw_device, device);
>  }
> @@ -229,7 +229,7 @@ struct fw_unit {
>         struct fw_attribute_group attribute_group;
>  };
>
> -static inline struct fw_unit *fw_unit(struct device *dev)
> +static inline struct fw_unit *fw_unit(const struct device *dev)
>  {
>         return container_of(dev, struct fw_unit, device);
>  }
> @@ -246,7 +246,7 @@ static inline void fw_unit_put(struct fw_unit *unit)
>         put_device(&unit->device);
>  }
>
> -static inline struct fw_device *fw_parent_device(struct fw_unit *unit)
> +static inline struct fw_device *fw_parent_device(const struct fw_unit *unit)
>  {
>         return fw_device(unit->device.parent);
>  }
> diff --git a/include/linux/i3c/device.h b/include/linux/i3c/device.h
> index 8242e13e7b0b..cda61c1d6d60 100644
> --- a/include/linux/i3c/device.h
> +++ b/include/linux/i3c/device.h
> @@ -186,7 +186,7 @@ static inline struct i3c_driver *drv_to_i3cdrv(struct device_driver *drv)
>  }
>
>  struct device *i3cdev_to_dev(struct i3c_device *i3cdev);
> -struct i3c_device *dev_to_i3cdev(struct device *dev);
> +struct i3c_device *dev_to_i3cdev(const struct device *dev);
>
>  const struct i3c_device_id *
>  i3c_device_match_id(struct i3c_device *i3cdev,
> @@ -293,7 +293,7 @@ int i3c_device_do_priv_xfers(struct i3c_device *dev,
>                              struct i3c_priv_xfer *xfers,
>                              int nxfers);
>
> -void i3c_device_get_info(struct i3c_device *dev, struct i3c_device_info *info);
> +void i3c_device_get_info(const struct i3c_device *dev, struct i3c_device_info *info);
>
>  struct i3c_ibi_payload {
>         unsigned int len;
> diff --git a/include/linux/of_device.h b/include/linux/of_device.h
> index ab7d557d541d..f4b57614979d 100644
> --- a/include/linux/of_device.h
> +++ b/include/linux/of_device.h
> @@ -36,7 +36,7 @@ extern ssize_t of_device_modalias(struct device *dev, char *str, ssize_t len);
>  extern int of_device_request_module(struct device *dev);
>
>  extern void of_device_uevent(const struct device *dev, struct kobj_uevent_env *env);
> -extern int of_device_uevent_modalias(struct device *dev, struct kobj_uevent_env *env);
> +extern int of_device_uevent_modalias(const struct device *dev, struct kobj_uevent_env *env);
>
>  static inline struct device_node *of_cpu_device_node_get(int cpu)
>  {
> @@ -83,7 +83,7 @@ static inline int of_device_request_module(struct device *dev)
>         return -ENODEV;
>  }
>
> -static inline int of_device_uevent_modalias(struct device *dev,
> +static inline int of_device_uevent_modalias(const struct device *dev,
>                                    struct kobj_uevent_env *env)
>  {
>         return -ENODEV;
> diff --git a/include/linux/soundwire/sdw_type.h b/include/linux/soundwire/sdw_type.h
> index 52eb66cd11bc..d8c27f1e5559 100644
> --- a/include/linux/soundwire/sdw_type.h
> +++ b/include/linux/soundwire/sdw_type.h
> @@ -21,7 +21,7 @@ static inline int is_sdw_slave(const struct device *dev)
>  int __sdw_register_driver(struct sdw_driver *drv, struct module *owner);
>  void sdw_unregister_driver(struct sdw_driver *drv);
>
> -int sdw_slave_uevent(struct device *dev, struct kobj_uevent_env *env);
> +int sdw_slave_uevent(const struct device *dev, struct kobj_uevent_env *env);
>
>  /**
>   * module_sdw_driver() - Helper macro for registering a Soundwire driver
> diff --git a/include/linux/surface_aggregator/device.h b/include/linux/surface_aggregator/device.h
> index 46c45d1b6368..a5dff729edb7 100644
> --- a/include/linux/surface_aggregator/device.h
> +++ b/include/linux/surface_aggregator/device.h
> @@ -229,7 +229,7 @@ static inline bool is_ssam_device(struct device *d)
>   * Return: Returns a pointer to the &struct ssam_device wrapping the given
>   * device @d.
>   */
> -static inline struct ssam_device *to_ssam_device(struct device *d)
> +static inline struct ssam_device *to_ssam_device(const struct device *d)
>  {
>         return container_of(d, struct ssam_device, dev);
>  }
> --
> 2.38.1
>

Maximilian Luz Nov. 23, 2022, 1:14 p.m. UTC | #2

Hi,

On 11/23/22 13:25, Greg Kroah-Hartman wrote:
> The uevent() callback in struct device_type should not be modifying the
> device that is passed into it, so mark it as a const * and propagate the
> function signature changes out into all relevant subsystems that use
> this callback.

[...]

> diff --git a/drivers/platform/surface/aggregator/bus.c b/drivers/platform/surface/aggregator/bus.c
> index de539938896e..407eb55050a6 100644
> --- a/drivers/platform/surface/aggregator/bus.c
> +++ b/drivers/platform/surface/aggregator/bus.c
> @@ -35,9 +35,9 @@ static struct attribute *ssam_device_attrs[] = {
>   };
>   ATTRIBUTE_GROUPS(ssam_device);
>   
> -static int ssam_device_uevent(struct device *dev, struct kobj_uevent_env *env)
> +static int ssam_device_uevent(const struct device *dev, struct kobj_uevent_env *env)
>   {
> -	struct ssam_device *sdev = to_ssam_device(dev);
> +	const struct ssam_device *sdev = to_ssam_device(dev);
>   
>   	return add_uevent_var(env, "MODALIAS=ssam:d%02Xc%02Xt%02Xi%02Xf%02X",
>   			      sdev->uid.domain, sdev->uid.category,

[...]

> --- a/include/linux/surface_aggregator/device.h
> +++ b/include/linux/surface_aggregator/device.h
> @@ -229,7 +229,7 @@ static inline bool is_ssam_device(struct device *d)
>    * Return: Returns a pointer to the &struct ssam_device wrapping the given
>    * device @d.
>    */
> -static inline struct ssam_device *to_ssam_device(struct device *d)
> +static inline struct ssam_device *to_ssam_device(const struct device *d)
>   {
>   	return container_of(d, struct ssam_device, dev);
>   }

I am slightly conflicted about this change as that now more or less
implicitly drops the const. So I'm wondering if it wouldn't be better to
either create a function specifically for const pointers or to just
open-code it in the instance above.

I guess we could also convert this to a macro. Then at least there
wouldn't be an explicit and potentially misleading const-conversion
indicated in the function signature.

Regards,
Max

Andy Shevchenko Nov. 23, 2022, 1:34 p.m. UTC | #3

On Wed, Nov 23, 2022 at 02:14:31PM +0100, Maximilian Luz wrote:
> On 11/23/22 13:25, Greg Kroah-Hartman wrote:
> > The uevent() callback in struct device_type should not be modifying the
> > device that is passed into it, so mark it as a const * and propagate the
> > function signature changes out into all relevant subsystems that use
> > this callback.

[...]

> > -static inline struct ssam_device *to_ssam_device(struct device *d)
> > +static inline struct ssam_device *to_ssam_device(const struct device *d)
> >   {
> >   	return container_of(d, struct ssam_device, dev);
> >   }
> 
> I am slightly conflicted about this change as that now more or less
> implicitly drops the const. So I'm wondering if it wouldn't be better to
> either create a function specifically for const pointers or to just
> open-code it in the instance above.
> 
> I guess we could also convert this to a macro. Then at least there
> wouldn't be an explicit and potentially misleading const-conversion
> indicated in the function signature.

This is an intermediate step as far as I know since moving container_of to
recognize const is a bit noisy right now. I guess you can find a discussion
on the topic between Greg and Sakari.

Mika Westerberg Nov. 23, 2022, 1:56 p.m. UTC | #4

On Wed, Nov 23, 2022 at 01:25:21PM +0100, Greg Kroah-Hartman wrote:
> The uevent() callback in struct device_type should not be modifying the
> device that is passed into it, so mark it as a const * and propagate the
> function signature changes out into all relevant subsystems that use
> this callback.
> 
> Cc: Jens Axboe <[e-mail]>
> Cc: "Rafael J. Wysocki" <[e-mail]>
> Cc: Len Brown <[e-mail]>
> Cc: Stefan Richter <[e-mail]>
> Cc: Wolfram Sang <[e-mail]>
> Cc: Alexandre Belloni <[e-mail]>
> Cc: Dmitry Torokhov <[e-mail]>
> Cc: Sean Young <[e-mail]>
> Cc: Mauro Carvalho Chehab <[e-mail]>
> Cc: Rob Herring <[e-mail]>
> Cc: Frank Rowand <[e-mail]>
> Cc: Maximilian Luz <[e-mail]>
> Cc: Hans de Goede <[e-mail]>
> Cc: Mark Gross <[e-mail]>
> Cc: Vinod Koul <[e-mail]>
> Cc: Bard Liao <[e-mail]>
> Cc: Pierre-Louis Bossart <[e-mail]>
> Cc: Sanyog Kale <[e-mail]>
> Cc: Andreas Noever <[e-mail]>
> Cc: Michael Jamet <[e-mail]>
> Cc: Mika Westerberg <[e-mail]>

Acked-by: Mika Westerberg <[e-mail]> # for Thunderbolt

Maximilian Luz Nov. 23, 2022, 1:59 p.m. UTC | #5

On 11/23/22 14:34, Andy Shevchenko wrote:
> On Wed, Nov 23, 2022 at 02:14:31PM +0100, Maximilian Luz wrote:
>> On 11/23/22 13:25, Greg Kroah-Hartman wrote:
>>> The uevent() callback in struct device_type should not be modifying the
>>> device that is passed into it, so mark it as a const * and propagate the
>>> function signature changes out into all relevant subsystems that use
>>> this callback.
> 
> [...]
> 
>>> -static inline struct ssam_device *to_ssam_device(struct device *d)
>>> +static inline struct ssam_device *to_ssam_device(const struct device *d)
>>>    {
>>>    	return container_of(d, struct ssam_device, dev);
>>>    }
>>
>> I am slightly conflicted about this change as that now more or less
>> implicitly drops the const. So I'm wondering if it wouldn't be better to
>> either create a function specifically for const pointers or to just
>> open-code it in the instance above.
>>
>> I guess we could also convert this to a macro. Then at least there
>> wouldn't be an explicit and potentially misleading const-conversion
>> indicated in the function signature.
> 
> This is an intermediate step as far as I know since moving container_of to
> recognize const is a bit noisy right now. I guess you can find a discussion
> on the topic between Greg and Sakari.

Thanks! I assume you are referring to the following?

	https://lore.kernel.org/lkml/[e-mail]/T/

As far as I can tell this is only a warning in documentation, not
compile time (which would probably be impossible?).

As I've said I'd be fine with converting the function to a macro (and
preferably adding a similar warning like the one proposed in that
thread). The point that irks me up is just that, as proposed, the
function signature would now advertise a conversion that should never be
happening.

Having two separate functions would create a compile-time guarantee, so
I'd prefer that, but I can understand if that might be considered too
noisy in code. Or if there is a push to make container_of() emit a
compile-time warning I'd also be perfectly happy with converting it to a
macro now as that'd alleviate the need for functions in the future.

Regards,
Max

Matthew Wilcox Nov. 23, 2022, 2:52 p.m. UTC | #6

On Wed, Nov 23, 2022 at 02:59:00PM +0100, Maximilian Luz wrote:
> On 11/23/22 14:34, Andy Shevchenko wrote:
> > On Wed, Nov 23, 2022 at 02:14:31PM +0100, Maximilian Luz wrote:
> > > On 11/23/22 13:25, Greg Kroah-Hartman wrote:
> > > > The uevent() callback in struct device_type should not be modifying the
> > > > device that is passed into it, so mark it as a const * and propagate the
> > > > function signature changes out into all relevant subsystems that use
> > > > this callback.
> > 
> > [...]
> > 
> > > > -static inline struct ssam_device *to_ssam_device(struct device *d)
> > > > +static inline struct ssam_device *to_ssam_device(const struct device *d)
> > > >    {
> > > >    	return container_of(d, struct ssam_device, dev);
> > > >    }
> > > 
> > > I am slightly conflicted about this change as that now more or less
> > > implicitly drops the const. So I'm wondering if it wouldn't be better to
> > > either create a function specifically for const pointers or to just
> > > open-code it in the instance above.
> > > 
> > > I guess we could also convert this to a macro. Then at least there
> > > wouldn't be an explicit and potentially misleading const-conversion
> > > indicated in the function signature.
> > 
> > This is an intermediate step as far as I know since moving container_of to
> > recognize const is a bit noisy right now. I guess you can find a discussion
> > on the topic between Greg and Sakari.
> 
> Thanks! I assume you are referring to the following?
> 
> 	https://lore.kernel.org/lkml/[e-mail]/T/
> 
> As far as I can tell this is only a warning in documentation, not
> compile time (which would probably be impossible?).
> 
> As I've said I'd be fine with converting the function to a macro (and
> preferably adding a similar warning like the one proposed in that
> thread). The point that irks me up is just that, as proposed, the
> function signature would now advertise a conversion that should never be
> happening.
> 
> Having two separate functions would create a compile-time guarantee, so
> I'd prefer that, but I can understand if that might be considered too
> noisy in code. Or if there is a push to make container_of() emit a
> compile-time warning I'd also be perfectly happy with converting it to a
> macro now as that'd alleviate the need for functions in the future.

Can't we do:

static inline const struct ssam_device *to_ssam_device(const struct device *d)
{
	return container_of(d, const struct ssam_device, dev);
}

Maximilian Luz Nov. 23, 2022, 3:14 p.m. UTC | #7

On 11/23/22 15:52, Matthew Wilcox wrote:
> On Wed, Nov 23, 2022 at 02:59:00PM +0100, Maximilian Luz wrote:
>> On 11/23/22 14:34, Andy Shevchenko wrote:
>>> On Wed, Nov 23, 2022 at 02:14:31PM +0100, Maximilian Luz wrote:
>>>> On 11/23/22 13:25, Greg Kroah-Hartman wrote:
>>>>> The uevent() callback in struct device_type should not be modifying the
>>>>> device that is passed into it, so mark it as a const * and propagate the
>>>>> function signature changes out into all relevant subsystems that use
>>>>> this callback.
>>>
>>> [...]
>>>
>>>>> -static inline struct ssam_device *to_ssam_device(struct device *d)
>>>>> +static inline struct ssam_device *to_ssam_device(const struct device *d)
>>>>>     {
>>>>>     	return container_of(d, struct ssam_device, dev);
>>>>>     }
>>>>
>>>> I am slightly conflicted about this change as that now more or less
>>>> implicitly drops the const. So I'm wondering if it wouldn't be better to
>>>> either create a function specifically for const pointers or to just
>>>> open-code it in the instance above.
>>>>
>>>> I guess we could also convert this to a macro. Then at least there
>>>> wouldn't be an explicit and potentially misleading const-conversion
>>>> indicated in the function signature.
>>>
>>> This is an intermediate step as far as I know since moving container_of to
>>> recognize const is a bit noisy right now. I guess you can find a discussion
>>> on the topic between Greg and Sakari.
>>
>> Thanks! I assume you are referring to the following?
>>
>> 	https://lore.kernel.org/lkml/[e-mail]/T/
>>
>> As far as I can tell this is only a warning in documentation, not
>> compile time (which would probably be impossible?).
>>
>> As I've said I'd be fine with converting the function to a macro (and
>> preferably adding a similar warning like the one proposed in that
>> thread). The point that irks me up is just that, as proposed, the
>> function signature would now advertise a conversion that should never be
>> happening.
>>
>> Having two separate functions would create a compile-time guarantee, so
>> I'd prefer that, but I can understand if that might be considered too
>> noisy in code. Or if there is a push to make container_of() emit a
>> compile-time warning I'd also be perfectly happy with converting it to a
>> macro now as that'd alleviate the need for functions in the future.
> 
> Can't we do:
> 
> static inline const struct ssam_device *to_ssam_device(const struct device *d)
> {
> 	return container_of(d, const struct ssam_device, dev);
> }

There are at least a couple of places (device/driver-management and
device-removal related, I think) using this function and requiring
non-const access.

A bunch of other instances could be converted to const-access only, but
that would require a couple more function signature changes (I should
probably set up a patch for that regardless of this here as being a bit
more strict about this makes sense).

Regards,
Max

Greg Kroah-Hartman Nov. 23, 2022, 3:37 p.m. UTC | #8

On Wed, Nov 23, 2022 at 02:52:59PM +0000, Matthew Wilcox wrote:
> On Wed, Nov 23, 2022 at 02:59:00PM +0100, Maximilian Luz wrote:
> > On 11/23/22 14:34, Andy Shevchenko wrote:
> > > On Wed, Nov 23, 2022 at 02:14:31PM +0100, Maximilian Luz wrote:
> > > > On 11/23/22 13:25, Greg Kroah-Hartman wrote:
> > > > > The uevent() callback in struct device_type should not be modifying the
> > > > > device that is passed into it, so mark it as a const * and propagate the
> > > > > function signature changes out into all relevant subsystems that use
> > > > > this callback.
> > > 
> > > [...]
> > > 
> > > > > -static inline struct ssam_device *to_ssam_device(struct device *d)
> > > > > +static inline struct ssam_device *to_ssam_device(const struct device *d)
> > > > >    {
> > > > >    	return container_of(d, struct ssam_device, dev);
> > > > >    }
> > > > 
> > > > I am slightly conflicted about this change as that now more or less
> > > > implicitly drops the const. So I'm wondering if it wouldn't be better to
> > > > either create a function specifically for const pointers or to just
> > > > open-code it in the instance above.
> > > > 
> > > > I guess we could also convert this to a macro. Then at least there
> > > > wouldn't be an explicit and potentially misleading const-conversion
> > > > indicated in the function signature.
> > > 
> > > This is an intermediate step as far as I know since moving container_of to
> > > recognize const is a bit noisy right now. I guess you can find a discussion
> > > on the topic between Greg and Sakari.
> > 
> > Thanks! I assume you are referring to the following?
> > 
> > 	https://lore.kernel.org/lkml/[e-mail]/T/
> > 
> > As far as I can tell this is only a warning in documentation, not
> > compile time (which would probably be impossible?).
> > 
> > As I've said I'd be fine with converting the function to a macro (and
> > preferably adding a similar warning like the one proposed in that
> > thread). The point that irks me up is just that, as proposed, the
> > function signature would now advertise a conversion that should never be
> > happening.
> > 
> > Having two separate functions would create a compile-time guarantee, so
> > I'd prefer that, but I can understand if that might be considered too
> > noisy in code. Or if there is a push to make container_of() emit a
> > compile-time warning I'd also be perfectly happy with converting it to a
> > macro now as that'd alleviate the need for functions in the future.
> 
> Can't we do:
> 
> static inline const struct ssam_device *to_ssam_device(const struct device *d)
> {
> 	return container_of(d, const struct ssam_device, dev);
> }
> 

You could, if you can always handle a const pointer coming out of this
function, but I don't think you can.

What you might want to do instead, and I'll be glad to do it for all of
the functions like this I change, is to do what we have for struct
device now:

static inline struct device *__kobj_to_dev(struct kobject *kobj)
{
        return container_of(kobj, struct device, kobj);
}

static inline const struct device *__kobj_to_dev_const(const struct kobject *kobj)
{
        return container_of(kobj, const struct device, kobj);
}

/*
 * container_of() will happily take a const * and spit back a non-const * as it
 * is just doing pointer math.  But we want to be a bit more careful in the
 * driver code, so manually force any const * of a kobject to also be a const *
 * to a device.
 */
#define kobj_to_dev(kobj)                                       \
        _Generic((kobj),                                        \
                 const struct kobject *: __kobj_to_dev_const,   \
                 struct kobject *: __kobj_to_dev)(kobj)


Want me to do the same thing here as well?

thanks,

greg k-h

Maximilian Luz Nov. 23, 2022, 3:48 p.m. UTC | #9

On 11/23/22 16:37, Greg Kroah-Hartman wrote:
> On Wed, Nov 23, 2022 at 02:52:59PM +0000, Matthew Wilcox wrote:
>> On Wed, Nov 23, 2022 at 02:59:00PM +0100, Maximilian Luz wrote:
>>> On 11/23/22 14:34, Andy Shevchenko wrote:
>>>> On Wed, Nov 23, 2022 at 02:14:31PM +0100, Maximilian Luz wrote:
>>>>> On 11/23/22 13:25, Greg Kroah-Hartman wrote:
>>>>>> The uevent() callback in struct device_type should not be modifying the
>>>>>> device that is passed into it, so mark it as a const * and propagate the
>>>>>> function signature changes out into all relevant subsystems that use
>>>>>> this callback.
>>>>
>>>> [...]
>>>>
>>>>>> -static inline struct ssam_device *to_ssam_device(struct device *d)
>>>>>> +static inline struct ssam_device *to_ssam_device(const struct device *d)
>>>>>>     {
>>>>>>     	return container_of(d, struct ssam_device, dev);
>>>>>>     }
>>>>>
>>>>> I am slightly conflicted about this change as that now more or less
>>>>> implicitly drops the const. So I'm wondering if it wouldn't be better to
>>>>> either create a function specifically for const pointers or to just
>>>>> open-code it in the instance above.
>>>>>
>>>>> I guess we could also convert this to a macro. Then at least there
>>>>> wouldn't be an explicit and potentially misleading const-conversion
>>>>> indicated in the function signature.
>>>>
>>>> This is an intermediate step as far as I know since moving container_of to
>>>> recognize const is a bit noisy right now. I guess you can find a discussion
>>>> on the topic between Greg and Sakari.
>>>
>>> Thanks! I assume you are referring to the following?
>>>
>>> 	https://lore.kernel.org/lkml/[e-mail]/T/
>>>
>>> As far as I can tell this is only a warning in documentation, not
>>> compile time (which would probably be impossible?).
>>>
>>> As I've said I'd be fine with converting the function to a macro (and
>>> preferably adding a similar warning like the one proposed in that
>>> thread). The point that irks me up is just that, as proposed, the
>>> function signature would now advertise a conversion that should never be
>>> happening.
>>>
>>> Having two separate functions would create a compile-time guarantee, so
>>> I'd prefer that, but I can understand if that might be considered too
>>> noisy in code. Or if there is a push to make container_of() emit a
>>> compile-time warning I'd also be perfectly happy with converting it to a
>>> macro now as that'd alleviate the need for functions in the future.
>>
>> Can't we do:
>>
>> static inline const struct ssam_device *to_ssam_device(const struct device *d)
>> {
>> 	return container_of(d, const struct ssam_device, dev);
>> }
>>
> 
> You could, if you can always handle a const pointer coming out of this
> function, but I don't think you can.
> 
> What you might want to do instead, and I'll be glad to do it for all of
> the functions like this I change, is to do what we have for struct
> device now:
> 
> static inline struct device *__kobj_to_dev(struct kobject *kobj)
> {
>          return container_of(kobj, struct device, kobj);
> }
> 
> static inline const struct device *__kobj_to_dev_const(const struct kobject *kobj)
> {
>          return container_of(kobj, const struct device, kobj);
> }
> 
> /*
>   * container_of() will happily take a const * and spit back a non-const * as it
>   * is just doing pointer math.  But we want to be a bit more careful in the
>   * driver code, so manually force any const * of a kobject to also be a const *
>   * to a device.
>   */
> #define kobj_to_dev(kobj)                                       \
>          _Generic((kobj),                                        \
>                   const struct kobject *: __kobj_to_dev_const,   \
>                   struct kobject *: __kobj_to_dev)(kobj)
> 
> 
> Want me to do the same thing here as well?

That looks great! Thanks!

I would very much prefer that.

Regards,
Max

Greg Kroah-Hartman Nov. 23, 2022, 3:52 p.m. UTC | #10

On Wed, Nov 23, 2022 at 04:48:41PM +0100, Maximilian Luz wrote:
> On 11/23/22 16:37, Greg Kroah-Hartman wrote:
> > On Wed, Nov 23, 2022 at 02:52:59PM +0000, Matthew Wilcox wrote:
> > > On Wed, Nov 23, 2022 at 02:59:00PM +0100, Maximilian Luz wrote:
> > > > On 11/23/22 14:34, Andy Shevchenko wrote:
> > > > > On Wed, Nov 23, 2022 at 02:14:31PM +0100, Maximilian Luz wrote:
> > > > > > On 11/23/22 13:25, Greg Kroah-Hartman wrote:
> > > > > > > The uevent() callback in struct device_type should not be modifying the
> > > > > > > device that is passed into it, so mark it as a const * and propagate the
> > > > > > > function signature changes out into all relevant subsystems that use
> > > > > > > this callback.
> > > > > 
> > > > > [...]
> > > > > 
> > > > > > > -static inline struct ssam_device *to_ssam_device(struct device *d)
> > > > > > > +static inline struct ssam_device *to_ssam_device(const struct device *d)
> > > > > > >     {
> > > > > > >     	return container_of(d, struct ssam_device, dev);
> > > > > > >     }
> > > > > > 
> > > > > > I am slightly conflicted about this change as that now more or less
> > > > > > implicitly drops the const. So I'm wondering if it wouldn't be better to
> > > > > > either create a function specifically for const pointers or to just
> > > > > > open-code it in the instance above.
> > > > > > 
> > > > > > I guess we could also convert this to a macro. Then at least there
> > > > > > wouldn't be an explicit and potentially misleading const-conversion
> > > > > > indicated in the function signature.
> > > > > 
> > > > > This is an intermediate step as far as I know since moving container_of to
> > > > > recognize const is a bit noisy right now. I guess you can find a discussion
> > > > > on the topic between Greg and Sakari.
> > > > 
> > > > Thanks! I assume you are referring to the following?
> > > > 
> > > > 	https://lore.kernel.org/lkml/[e-mail]/T/
> > > > 
> > > > As far as I can tell this is only a warning in documentation, not
> > > > compile time (which would probably be impossible?).
> > > > 
> > > > As I've said I'd be fine with converting the function to a macro (and
> > > > preferably adding a similar warning like the one proposed in that
> > > > thread). The point that irks me up is just that, as proposed, the
> > > > function signature would now advertise a conversion that should never be
> > > > happening.
> > > > 
> > > > Having two separate functions would create a compile-time guarantee, so
> > > > I'd prefer that, but I can understand if that might be considered too
> > > > noisy in code. Or if there is a push to make container_of() emit a
> > > > compile-time warning I'd also be perfectly happy with converting it to a
> > > > macro now as that'd alleviate the need for functions in the future.
> > > 
> > > Can't we do:
> > > 
> > > static inline const struct ssam_device *to_ssam_device(const struct device *d)
> > > {
> > > 	return container_of(d, const struct ssam_device, dev);
> > > }
> > > 
> > 
> > You could, if you can always handle a const pointer coming out of this
> > function, but I don't think you can.
> > 
> > What you might want to do instead, and I'll be glad to do it for all of
> > the functions like this I change, is to do what we have for struct
> > device now:
> > 
> > static inline struct device *__kobj_to_dev(struct kobject *kobj)
> > {
> >          return container_of(kobj, struct device, kobj);
> > }
> > 
> > static inline const struct device *__kobj_to_dev_const(const struct kobject *kobj)
> > {
> >          return container_of(kobj, const struct device, kobj);
> > }
> > 
> > /*
> >   * container_of() will happily take a const * and spit back a non-const * as it
> >   * is just doing pointer math.  But we want to be a bit more careful in the
> >   * driver code, so manually force any const * of a kobject to also be a const *
> >   * to a device.
> >   */
> > #define kobj_to_dev(kobj)                                       \
> >          _Generic((kobj),                                        \
> >                   const struct kobject *: __kobj_to_dev_const,   \
> >                   struct kobject *: __kobj_to_dev)(kobj)
> > 
> > 
> > Want me to do the same thing here as well?
> 
> That looks great! Thanks!
> 
> I would very much prefer that.

Ok, will respin this patch as at least 2 individual patches, one that
does the change to to_ssam_device() and the next that does the bus-wide
changes.

I'll review the other container_of() users in this patch as well to see
if they can be converted as well.

thanks,

greg k-h

Jason Gunthorpe Nov. 23, 2022, 4:25 p.m. UTC | #11

On Wed, Nov 23, 2022 at 04:37:59PM +0100, Greg Kroah-Hartman wrote:
> static inline struct device *__kobj_to_dev(struct kobject *kobj)
> {
>         return container_of(kobj, struct device, kobj);
> }
> 
> static inline const struct device *__kobj_to_dev_const(const struct kobject *kobj)
> {
>         return container_of(kobj, const struct device, kobj);
> }
> 
> /*
>  * container_of() will happily take a const * and spit back a non-const * as it
>  * is just doing pointer math.  But we want to be a bit more careful in the
>  * driver code, so manually force any const * of a kobject to also be a const *
>  * to a device.
>  */
> #define kobj_to_dev(kobj)                                       \
>         _Generic((kobj),                                        \
>                  const struct kobject *: __kobj_to_dev_const,   \
>                  struct kobject *: __kobj_to_dev)(kobj)
> 
> 
> Want me to do the same thing here as well?

It would be nice to have a shared macro code gen all of the above
instead of copy and pasting it. Then maybe other cases beyond struct
device could adopt const too..

Jason

Greg Kroah-Hartman Nov. 23, 2022, 5:01 p.m. UTC | #12

On Wed, Nov 23, 2022 at 12:25:32PM -0400, Jason Gunthorpe wrote:
> On Wed, Nov 23, 2022 at 04:37:59PM +0100, Greg Kroah-Hartman wrote:
> > static inline struct device *__kobj_to_dev(struct kobject *kobj)
> > {
> >         return container_of(kobj, struct device, kobj);
> > }
> > 
> > static inline const struct device *__kobj_to_dev_const(const struct kobject *kobj)
> > {
> >         return container_of(kobj, const struct device, kobj);
> > }
> > 
> > /*
> >  * container_of() will happily take a const * and spit back a non-const * as it
> >  * is just doing pointer math.  But we want to be a bit more careful in the
> >  * driver code, so manually force any const * of a kobject to also be a const *
> >  * to a device.
> >  */
> > #define kobj_to_dev(kobj)                                       \
> >         _Generic((kobj),                                        \
> >                  const struct kobject *: __kobj_to_dev_const,   \
> >                  struct kobject *: __kobj_to_dev)(kobj)
> > 
> > 
> > Want me to do the same thing here as well?
> 
> It would be nice to have a shared macro code gen all of the above
> instead of copy and pasting it. Then maybe other cases beyond struct
> device could adopt const too..

I think I tried to create such a beast, but failed, so ended up
open-coding it in a few places in the USB headers already.  I can try it
again, but the redirection gets tricky (defines creating defines...)

thanks,

greg k-h

Jason Gunthorpe Nov. 23, 2022, 5:29 p.m. UTC | #13

On Wed, Nov 23, 2022 at 06:01:47PM +0100, Greg Kroah-Hartman wrote:
> On Wed, Nov 23, 2022 at 12:25:32PM -0400, Jason Gunthorpe wrote:
> > On Wed, Nov 23, 2022 at 04:37:59PM +0100, Greg Kroah-Hartman wrote:
> > > static inline struct device *__kobj_to_dev(struct kobject *kobj)
> > > {
> > >         return container_of(kobj, struct device, kobj);
> > > }
> > > 
> > > static inline const struct device *__kobj_to_dev_const(const struct kobject *kobj)
> > > {
> > >         return container_of(kobj, const struct device, kobj);
> > > }
> > > 
> > > /*
> > >  * container_of() will happily take a const * and spit back a non-const * as it
> > >  * is just doing pointer math.  But we want to be a bit more careful in the
> > >  * driver code, so manually force any const * of a kobject to also be a const *
> > >  * to a device.
> > >  */
> > > #define kobj_to_dev(kobj)                                       \
> > >         _Generic((kobj),                                        \
> > >                  const struct kobject *: __kobj_to_dev_const,   \
> > >                  struct kobject *: __kobj_to_dev)(kobj)
> > > 
> > > 
> > > Want me to do the same thing here as well?
> > 
> > It would be nice to have a shared macro code gen all of the above
> > instead of copy and pasting it. Then maybe other cases beyond struct
> > device could adopt const too..
> 
> I think I tried to create such a beast, but failed, so ended up
> open-coding it in a few places in the USB headers already.  I can try it
> again, but the redirection gets tricky (defines creating defines...)

This seems OK:

#define generic_container_of(in_type, in, out_type, out_member) \
	_Generic(in,                                        \
                  const in_type *: ((const out_type *)container_of(in, out_type, out_member)),   \
                  in_type *: ((out_type *)container_of(in, out_type, out_member)) \
		  )

#define kobj_to_dev(__kobj) \
	generic_container_of(struct kobject, __kobj, struct device, kobj)

Jason

Matthew Wilcox Nov. 23, 2022, 5:49 p.m. UTC | #14

On Wed, Nov 23, 2022 at 01:29:56PM -0400, Jason Gunthorpe wrote:
> #define generic_container_of(in_type, in, out_type, out_member) \
> 	_Generic(in,                                        \
>                   const in_type *: ((const out_type *)container_of(in, out_type, out_member)),   \
>                   in_type *: ((out_type *)container_of(in, out_type, out_member)) \
> 		  )

There's a neat trick I found in seqlock.h:

#define generic_container_of(in_t, in, out_t, m)			\
	_Generic(*(in),							\
		const in_t: ((const out_t *)container_of(in, out_t, m)), \
		in_t: ((out_t *)container_of(in, out_type, m))	\
	)

and now it fits in 80 columns ;-)

> #define kobj_to_dev(__kobj) \
> 	generic_container_of(struct kobject, __kobj, struct device, kobj)
> 
> Jason

Jason Gunthorpe Nov. 23, 2022, 5:55 p.m. UTC | #15

On Wed, Nov 23, 2022 at 05:49:36PM +0000, Matthew Wilcox wrote:
> On Wed, Nov 23, 2022 at 01:29:56PM -0400, Jason Gunthorpe wrote:
> > #define generic_container_of(in_type, in, out_type, out_member) \
> > 	_Generic(in,                                        \
> >                   const in_type *: ((const out_type *)container_of(in, out_type, out_member)),   \
> >                   in_type *: ((out_type *)container_of(in, out_type, out_member)) \
> > 		  )
> 
> There's a neat trick I found in seqlock.h:
> 
> #define generic_container_of(in_t, in, out_t, m)			\
> 	_Generic(*(in),							\
> 		const in_t: ((const out_t *)container_of(in, out_t, m)), \
> 		in_t: ((out_t *)container_of(in, out_type, m))	\
> 	)
>
> and now it fits in 80 columns ;-)

Aside from less letters, is their another benifit to using *(in) ?

Jason

Matthew Wilcox Nov. 23, 2022, 6 p.m. UTC | #16

On Wed, Nov 23, 2022 at 01:55:42PM -0400, Jason Gunthorpe wrote:
> On Wed, Nov 23, 2022 at 05:49:36PM +0000, Matthew Wilcox wrote:
> > On Wed, Nov 23, 2022 at 01:29:56PM -0400, Jason Gunthorpe wrote:
> > > #define generic_container_of(in_type, in, out_type, out_member) \
> > > 	_Generic(in,                                        \
> > >                   const in_type *: ((const out_type *)container_of(in, out_type, out_member)),   \
> > >                   in_type *: ((out_type *)container_of(in, out_type, out_member)) \
> > > 		  )
> > 
> > There's a neat trick I found in seqlock.h:
> > 
> > #define generic_container_of(in_t, in, out_t, m)			\
> > 	_Generic(*(in),							\
> > 		const in_t: ((const out_t *)container_of(in, out_t, m)), \
> > 		in_t: ((out_t *)container_of(in, out_type, m))	\
> > 	)
> >
> > and now it fits in 80 columns ;-)
> 
> Aside from less letters, is their another benifit to using *(in) ?

I don't think so.  It just looks nicer to me than putting the star in
each case.  If I'd thought of it, I would have done it to page_folio(),
but I won't change it now.

Greg Kroah-Hartman Nov. 23, 2022, 6:10 p.m. UTC | #17

On Wed, Nov 23, 2022 at 05:49:36PM +0000, Matthew Wilcox wrote:
> On Wed, Nov 23, 2022 at 01:29:56PM -0400, Jason Gunthorpe wrote:
> > #define generic_container_of(in_type, in, out_type, out_member) \
> > 	_Generic(in,                                        \
> >                   const in_type *: ((const out_type *)container_of(in, out_type, out_member)),   \
> >                   in_type *: ((out_type *)container_of(in, out_type, out_member)) \
> > 		  )
> 
> There's a neat trick I found in seqlock.h:
> 
> #define generic_container_of(in_t, in, out_t, m)			\
> 	_Generic(*(in),							\
> 		const in_t: ((const out_t *)container_of(in, out_t, m)), \
> 		in_t: ((out_t *)container_of(in, out_type, m))	\
> 	)
> 
> and now it fits in 80 columns ;-)

Nice trick!  Dropping the inline functions is a bit different, let me
see if that still gives a sane error if we pass an incorrect type or
mess with the const * the wrong way.  I'll run some tests tomorrow
afternoon...

thanks,

greg k-h

Jason Gunthorpe Nov. 23, 2022, 6:25 p.m. UTC | #18

On Wed, Nov 23, 2022 at 07:10:49PM +0100, Greg Kroah-Hartman wrote:
> On Wed, Nov 23, 2022 at 05:49:36PM +0000, Matthew Wilcox wrote:
> > On Wed, Nov 23, 2022 at 01:29:56PM -0400, Jason Gunthorpe wrote:
> > > #define generic_container_of(in_type, in, out_type, out_member) \
> > > 	_Generic(in,                                        \
> > >                   const in_type *: ((const out_type *)container_of(in, out_type, out_member)),   \
> > >                   in_type *: ((out_type *)container_of(in, out_type, out_member)) \
> > > 		  )
> > 
> > There's a neat trick I found in seqlock.h:
> > 
> > #define generic_container_of(in_t, in, out_t, m)			\
> > 	_Generic(*(in),							\
> > 		const in_t: ((const out_t *)container_of(in, out_t, m)), \
> > 		in_t: ((out_t *)container_of(in, out_type, m))	\
> > 	)
> > 
> > and now it fits in 80 columns ;-)
> 
> Nice trick!  Dropping the inline functions is a bit different, let me
> see if that still gives a sane error if we pass an incorrect type or
> mess with the const * the wrong way.  I'll run some tests tomorrow
> afternoon...

The errors in some cases are very verbose, but it is somewhat
understandable - the worst is when _Generic fails to match anything,
but also at least clang partially expanded container_of and it throws
other assertions too.

I also wonder if this could just be rolled into the normal
container_of.

in_type would have to be derived like:

  in_type = typeof((out_type *)NULL)->out_member)

But I don't know if you can use typeof in a generic type matching expression..

Jason

Greg Kroah-Hartman Nov. 23, 2022, 7:06 p.m. UTC | #19

On Wed, Nov 23, 2022 at 02:25:59PM -0400, Jason Gunthorpe wrote:
> On Wed, Nov 23, 2022 at 07:10:49PM +0100, Greg Kroah-Hartman wrote:
> > On Wed, Nov 23, 2022 at 05:49:36PM +0000, Matthew Wilcox wrote:
> > > On Wed, Nov 23, 2022 at 01:29:56PM -0400, Jason Gunthorpe wrote:
> > > > #define generic_container_of(in_type, in, out_type, out_member) \
> > > > 	_Generic(in,                                        \
> > > >                   const in_type *: ((const out_type *)container_of(in, out_type, out_member)),   \
> > > >                   in_type *: ((out_type *)container_of(in, out_type, out_member)) \
> > > > 		  )
> > > 
> > > There's a neat trick I found in seqlock.h:
> > > 
> > > #define generic_container_of(in_t, in, out_t, m)			\
> > > 	_Generic(*(in),							\
> > > 		const in_t: ((const out_t *)container_of(in, out_t, m)), \
> > > 		in_t: ((out_t *)container_of(in, out_type, m))	\
> > > 	)
> > > 
> > > and now it fits in 80 columns ;-)
> > 
> > Nice trick!  Dropping the inline functions is a bit different, let me
> > see if that still gives a sane error if we pass an incorrect type or
> > mess with the const * the wrong way.  I'll run some tests tomorrow
> > afternoon...
> 
> The errors in some cases are very verbose, but it is somewhat
> understandable - the worst is when _Generic fails to match anything,
> but also at least clang partially expanded container_of and it throws
> other assertions too.
> 
> I also wonder if this could just be rolled into the normal
> container_of.

I think we might be able to now, my previous attempts with inline
functions prevented that.  I'll beat on that tomorrow...

> in_type would have to be derived like:
> 
>   in_type = typeof((out_type *)NULL)->out_member)
> 
> But I don't know if you can use typeof in a generic type matching expression..

Maybe that is what threw me before, I can't remember.  I do know we
tried a number of different attempts, can't recall the failed ones...

thanks,

greg k-h

Barnabás Pőcze Nov. 23, 2022, 11:24 p.m. UTC | #20

Hi


2022. november 23., szerda 20:06 keltezéssel, Greg Kroah-Hartman írta:


> On Wed, Nov 23, 2022 at 02:25:59PM -0400, Jason Gunthorpe wrote:
> 
> > On Wed, Nov 23, 2022 at 07:10:49PM +0100, Greg Kroah-Hartman wrote:
> > 
> > > On Wed, Nov 23, 2022 at 05:49:36PM +0000, Matthew Wilcox wrote:
> > > 
> > > > On Wed, Nov 23, 2022 at 01:29:56PM -0400, Jason Gunthorpe wrote:
> > > > 
> > > > > #define generic_container_of(in_type, in, out_type, out_member) \
> > > > > _Generic(in, \
> > > > > const in_type *: ((const out_type *)container_of(in, out_type, out_member)), \
> > > > > in_type *: ((out_type *)container_of(in, out_type, out_member)) \
> > > > > )
> > > > 
> > > > There's a neat trick I found in seqlock.h:
> > > > 
> > > > #define generic_container_of(in_t, in, out_t, m) \
> > > > _Generic(*(in), \
> > > > const in_t: ((const out_t *)container_of(in, out_t, m)), \
> > > > in_t: ((out_t *)container_of(in, out_type, m)) \
> > > > )
> > > > 
> > > > and now it fits in 80 columns ;-)
> > > 
> > > Nice trick! Dropping the inline functions is a bit different, let me
> > > see if that still gives a sane error if we pass an incorrect type or
> > > mess with the const * the wrong way. I'll run some tests tomorrow
> > > afternoon...
> > 
> > The errors in some cases are very verbose, but it is somewhat
> > understandable - the worst is when _Generic fails to match anything,
> > but also at least clang partially expanded container_of and it throws
> > other assertions too.
> > 
> > I also wonder if this could just be rolled into the normal
> > container_of.
> 
> 
> I think we might be able to now, my previous attempts with inline
> functions prevented that. I'll beat on that tomorrow...
> 
> > in_type would have to be derived like:
> > 
> > in_type = typeof((out_type *)NULL)->out_member)
> > 
> > But I don't know if you can use typeof in a generic type matching expression..
> 
> 
> Maybe that is what threw me before, I can't remember. I do know we
> tried a number of different attempts, can't recall the failed ones...
> 

I am sorry I haven't followed the previous discussion,
but has something like the following been considered?

  #define container_of2(ptr, type, member) \
  	_Generic((ptr), \
  		typeof_member(const type, member) *: container_of((ptr), const type, member), \
  		const void *: container_of((ptr), const type, member), \
  		default: container_of((ptr), type, member) \
  	)

This is not perfect by any means, but I believe it is a reasonable
improvement. It only really works reliably if the member type and
the specified `type` in the arguments are unqualified,
but I believe that should cover the majority of cases.

I have tried to build an x86-64 defconfig with this and there are
numerous const violations, but I haven't seen any false positives.


> [...]


Regards,
Barnabás Pőcze

Mauro Carvalho Chehab Nov. 25, 2022, 11:56 a.m. UTC | #21

Em Wed, 23 Nov 2022 13:25:21 +0100
Greg Kroah-Hartman <[e-mail]> escreveu:

> The uevent() callback in struct device_type should not be modifying the
> device that is passed into it, so mark it as a const * and propagate the
> function signature changes out into all relevant subsystems that use
> this callback.

Acked-by: Mauro Carvalho Chehab <[e-mail]>

> 
> Cc: Jens Axboe <[e-mail]>
> Cc: "Rafael J. Wysocki" <[e-mail]>
> Cc: Len Brown <[e-mail]>
> Cc: Stefan Richter <[e-mail]>
> Cc: Wolfram Sang <[e-mail]>
> Cc: Alexandre Belloni <[e-mail]>
> Cc: Dmitry Torokhov <[e-mail]>
> Cc: Sean Young <[e-mail]>
> Cc: Mauro Carvalho Chehab <[e-mail]>
> Cc: Rob Herring <[e-mail]>
> Cc: Frank Rowand <[e-mail]>
> Cc: Maximilian Luz <[e-mail]>
> Cc: Hans de Goede <[e-mail]>
> Cc: Mark Gross <[e-mail]>
> Cc: Vinod Koul <[e-mail]>
> Cc: Bard Liao <[e-mail]>
> Cc: Pierre-Louis Bossart <[e-mail]>
> Cc: Sanyog Kale <[e-mail]>
> Cc: Andreas Noever <[e-mail]>
> Cc: Michael Jamet <[e-mail]>
> Cc: Mika Westerberg <[e-mail]>
> Cc: Yehezkel Bernat <[e-mail]>
> Cc: Jiri Slaby <[e-mail]>
> Cc: Heikki Krogerus <[e-mail]>
> Cc: "Matthew Wilcox (Oracle)" <[e-mail]>
> Cc: "Martin K. Petersen" <[e-mail]>
> Cc: Chaitanya Kulkarni <[e-mail]>
> Cc: Ming Lei <[e-mail]>
> Cc: Jilin Yuan <[e-mail]>
> Cc: Alan Stern <[e-mail]>
> Cc: Andy Shevchenko <[e-mail]>
> Cc: Sakari Ailus <[e-mail]>
> Cc: Jason Gunthorpe <[e-mail]>
> Cc: Thomas Gleixner <[e-mail]>
> Cc: Ira Weiny <[e-mail]>
> Cc: Dan Williams <[e-mail]>
> Cc: Won Chung <[e-mail]>
> Cc: [e-mail]
> Cc: [e-mail]
> Cc: [e-mail]
> Cc: [e-mail]
> Cc: [e-mail]
> Cc: [e-mail]
> Cc: [e-mail]
> Cc: [e-mail]
> Cc: [e-mail]
> Cc: [e-mail]
> Cc: [e-mail]
> Cc: [e-mail]
> Cc: [e-mail]
> Signed-off-by: Greg Kroah-Hartman <[e-mail]>
> ---
>  block/partitions/core.c                   |  4 ++--
>  drivers/acpi/device_sysfs.c               |  8 ++++----
>  drivers/acpi/internal.h                   |  2 +-
>  drivers/firewire/core-device.c            |  8 ++++----
>  drivers/i2c/i2c-core-base.c               |  4 ++--
>  drivers/i3c/device.c                      |  4 ++--
>  drivers/i3c/master.c                      |  4 ++--
>  drivers/input/input.c                     | 16 ++++++++--------
>  drivers/media/rc/rc-main.c                |  2 +-
>  drivers/of/device.c                       |  4 ++--
>  drivers/platform/surface/aggregator/bus.c |  4 ++--
>  drivers/soundwire/bus_type.c              |  4 ++--
>  drivers/thunderbolt/switch.c              |  4 ++--
>  drivers/thunderbolt/tb.h                  |  2 +-
>  drivers/thunderbolt/xdomain.c             |  6 +++---
>  drivers/tty/serdev/core.c                 |  2 +-
>  drivers/usb/core/message.c                |  8 ++++----
>  drivers/usb/core/usb.c                    |  4 ++--
>  drivers/usb/phy/phy.c                     |  6 +++---
>  drivers/usb/roles/class.c                 |  3 +--
>  drivers/usb/typec/class.c                 |  2 +-
>  include/linux/acpi.h                      |  4 ++--
>  include/linux/device.h                    |  2 +-
>  include/linux/firewire.h                  |  6 +++---
>  include/linux/i3c/device.h                |  4 ++--
>  include/linux/of_device.h                 |  4 ++--
>  include/linux/soundwire/sdw_type.h        |  2 +-
>  include/linux/surface_aggregator/device.h |  2 +-
>  28 files changed, 62 insertions(+), 63 deletions(-)
> 
> diff --git a/block/partitions/core.c b/block/partitions/core.c
> index b8112f52d388..7b8ef6296abd 100644
> --- a/block/partitions/core.c
> +++ b/block/partitions/core.c
> @@ -254,9 +254,9 @@ static void part_release(struct device *dev)
>  	iput(dev_to_bdev(dev)->bd_inode);
>  }
>  
> -static int part_uevent(struct device *dev, struct kobj_uevent_env *env)
> +static int part_uevent(const struct device *dev, struct kobj_uevent_env *env)
>  {
> -	struct block_device *part = dev_to_bdev(dev);
> +	const struct block_device *part = dev_to_bdev(dev);
>  
>  	add_uevent_var(env, "PARTN=%u", part->bd_partno);
>  	if (part->bd_meta_info && part->bd_meta_info->volname[0])
> diff --git a/drivers/acpi/device_sysfs.c b/drivers/acpi/device_sysfs.c
> index 120873dad2cc..daff2c0c5c52 100644
> --- a/drivers/acpi/device_sysfs.c
> +++ b/drivers/acpi/device_sysfs.c
> @@ -133,7 +133,7 @@ static void acpi_hide_nondev_subnodes(struct acpi_device_data *data)
>   *         -EINVAL: output error
>   *         -ENOMEM: output is truncated
>   */
> -static int create_pnp_modalias(struct acpi_device *acpi_dev, char *modalias,
> +static int create_pnp_modalias(const struct acpi_device *acpi_dev, char *modalias,
>  			       int size)
>  {
>  	int len;
> @@ -191,7 +191,7 @@ static int create_pnp_modalias(struct acpi_device *acpi_dev, char *modalias,
>   * only be called for devices having ACPI_DT_NAMESPACE_HID in their list of
>   * ACPI/PNP IDs.
>   */
> -static int create_of_modalias(struct acpi_device *acpi_dev, char *modalias,
> +static int create_of_modalias(const struct acpi_device *acpi_dev, char *modalias,
>  			      int size)
>  {
>  	struct acpi_buffer buf = { ACPI_ALLOCATE_BUFFER };
> @@ -239,7 +239,7 @@ static int create_of_modalias(struct acpi_device *acpi_dev, char *modalias,
>  	return len;
>  }
>  
> -int __acpi_device_uevent_modalias(struct acpi_device *adev,
> +int __acpi_device_uevent_modalias(const struct acpi_device *adev,
>  				  struct kobj_uevent_env *env)
>  {
>  	int len;
> @@ -277,7 +277,7 @@ int __acpi_device_uevent_modalias(struct acpi_device *adev,
>   * Because other buses do not support ACPI HIDs & CIDs, e.g. for a device with
>   * hid:IBM0001 and cid:ACPI0001 you get: "acpi:IBM0001:ACPI0001".
>   */
> -int acpi_device_uevent_modalias(struct device *dev, struct kobj_uevent_env *env)
> +int acpi_device_uevent_modalias(const struct device *dev, struct kobj_uevent_env *env)
>  {
>  	return __acpi_device_uevent_modalias(acpi_companion_match(dev), env);
>  }
> diff --git a/drivers/acpi/internal.h b/drivers/acpi/internal.h
> index 219c02df9a08..d422884eb3d0 100644
> --- a/drivers/acpi/internal.h
> +++ b/drivers/acpi/internal.h
> @@ -120,7 +120,7 @@ int acpi_bus_register_early_device(int type);
>                       Device Matching and Notification
>     -------------------------------------------------------------------------- */
>  struct acpi_device *acpi_companion_match(const struct device *dev);
> -int __acpi_device_uevent_modalias(struct acpi_device *adev,
> +int __acpi_device_uevent_modalias(const struct acpi_device *adev,
>  				  struct kobj_uevent_env *env);
>  
>  /* --------------------------------------------------------------------------
> diff --git a/drivers/firewire/core-device.c b/drivers/firewire/core-device.c
> index adddd8c45d0c..aa597cda0d88 100644
> --- a/drivers/firewire/core-device.c
> +++ b/drivers/firewire/core-device.c
> @@ -133,7 +133,7 @@ static void get_ids(const u32 *directory, int *id)
>  	}
>  }
>  
> -static void get_modalias_ids(struct fw_unit *unit, int *id)
> +static void get_modalias_ids(const struct fw_unit *unit, int *id)
>  {
>  	get_ids(&fw_parent_device(unit)->config_rom[5], id);
>  	get_ids(unit->directory, id);
> @@ -195,7 +195,7 @@ static void fw_unit_remove(struct device *dev)
>  	driver->remove(fw_unit(dev));
>  }
>  
> -static int get_modalias(struct fw_unit *unit, char *buffer, size_t buffer_size)
> +static int get_modalias(const struct fw_unit *unit, char *buffer, size_t buffer_size)
>  {
>  	int id[] = {0, 0, 0, 0};
>  
> @@ -206,9 +206,9 @@ static int get_modalias(struct fw_unit *unit, char *buffer, size_t buffer_size)
>  			id[0], id[1], id[2], id[3]);
>  }
>  
> -static int fw_unit_uevent(struct device *dev, struct kobj_uevent_env *env)
> +static int fw_unit_uevent(const struct device *dev, struct kobj_uevent_env *env)
>  {
> -	struct fw_unit *unit = fw_unit(dev);
> +	const struct fw_unit *unit = fw_unit(dev);
>  	char modalias[64];
>  
>  	get_modalias(unit, modalias, sizeof(modalias));
> diff --git a/drivers/i2c/i2c-core-base.c b/drivers/i2c/i2c-core-base.c
> index b4edf10e8fd0..fb16e33e52c6 100644
> --- a/drivers/i2c/i2c-core-base.c
> +++ b/drivers/i2c/i2c-core-base.c
> @@ -136,9 +136,9 @@ static int i2c_device_match(struct device *dev, struct device_driver *drv)
>  	return 0;
>  }
>  
> -static int i2c_device_uevent(struct device *dev, struct kobj_uevent_env *env)
> +static int i2c_device_uevent(const struct device *dev, struct kobj_uevent_env *env)
>  {
> -	struct i2c_client *client = to_i2c_client(dev);
> +	const struct i2c_client *client = to_i2c_client(dev);
>  	int rc;
>  
>  	rc = of_device_uevent_modalias(dev, env);
> diff --git a/drivers/i3c/device.c b/drivers/i3c/device.c
> index e92d3e9a52bd..05f8ab762e34 100644
> --- a/drivers/i3c/device.c
> +++ b/drivers/i3c/device.c
> @@ -58,7 +58,7 @@ EXPORT_SYMBOL_GPL(i3c_device_do_priv_xfers);
>   *
>   * Retrieve I3C dev info.
>   */
> -void i3c_device_get_info(struct i3c_device *dev,
> +void i3c_device_get_info(const struct i3c_device *dev,
>  			 struct i3c_device_info *info)
>  {
>  	if (!info)
> @@ -194,7 +194,7 @@ EXPORT_SYMBOL_GPL(i3cdev_to_dev);
>   *
>   * Return: a pointer to an I3C device object.
>   */
> -struct i3c_device *dev_to_i3cdev(struct device *dev)
> +struct i3c_device *dev_to_i3cdev(const struct device *dev)
>  {
>  	return container_of(dev, struct i3c_device, dev);
>  }
> diff --git a/drivers/i3c/master.c b/drivers/i3c/master.c
> index 351c81a929a6..bf1a2b2f34c4 100644
> --- a/drivers/i3c/master.c
> +++ b/drivers/i3c/master.c
> @@ -273,9 +273,9 @@ static struct attribute *i3c_device_attrs[] = {
>  };
>  ATTRIBUTE_GROUPS(i3c_device);
>  
> -static int i3c_device_uevent(struct device *dev, struct kobj_uevent_env *env)
> +static int i3c_device_uevent(const struct device *dev, struct kobj_uevent_env *env)
>  {
> -	struct i3c_device *i3cdev = dev_to_i3cdev(dev);
> +	const struct i3c_device *i3cdev = dev_to_i3cdev(dev);
>  	struct i3c_device_info devinfo;
>  	u16 manuf, part, ext;
>  
> diff --git a/drivers/input/input.c b/drivers/input/input.c
> index 50597165dc54..a612afffa196 100644
> --- a/drivers/input/input.c
> +++ b/drivers/input/input.c
> @@ -1371,7 +1371,7 @@ INPUT_DEV_STRING_ATTR_SHOW(phys);
>  INPUT_DEV_STRING_ATTR_SHOW(uniq);
>  
>  static int input_print_modalias_bits(char *buf, int size,
> -				     char name, unsigned long *bm,
> +				     char name, const unsigned long *bm,
>  				     unsigned int min_bit, unsigned int max_bit)
>  {
>  	int len = 0, i;
> @@ -1383,7 +1383,7 @@ static int input_print_modalias_bits(char *buf, int size,
>  	return len;
>  }
>  
> -static int input_print_modalias(char *buf, int size, struct input_dev *id,
> +static int input_print_modalias(char *buf, int size, const struct input_dev *id,
>  				int add_cr)
>  {
>  	int len;
> @@ -1431,7 +1431,7 @@ static ssize_t input_dev_show_modalias(struct device *dev,
>  }
>  static DEVICE_ATTR(modalias, S_IRUGO, input_dev_show_modalias, NULL);
>  
> -static int input_print_bitmap(char *buf, int buf_size, unsigned long *bitmap,
> +static int input_print_bitmap(char *buf, int buf_size, const unsigned long *bitmap,
>  			      int max, int add_cr);
>  
>  static ssize_t input_dev_show_properties(struct device *dev,
> @@ -1523,7 +1523,7 @@ static const struct attribute_group input_dev_id_attr_group = {
>  	.attrs	= input_dev_id_attrs,
>  };
>  
> -static int input_print_bitmap(char *buf, int buf_size, unsigned long *bitmap,
> +static int input_print_bitmap(char *buf, int buf_size, const unsigned long *bitmap,
>  			      int max, int add_cr)
>  {
>  	int i;
> @@ -1620,7 +1620,7 @@ static void input_dev_release(struct device *device)
>   * device bitfields.
>   */
>  static int input_add_uevent_bm_var(struct kobj_uevent_env *env,
> -				   const char *name, unsigned long *bitmap, int max)
> +				   const char *name, const unsigned long *bitmap, int max)
>  {
>  	int len;
>  
> @@ -1638,7 +1638,7 @@ static int input_add_uevent_bm_var(struct kobj_uevent_env *env,
>  }
>  
>  static int input_add_uevent_modalias_var(struct kobj_uevent_env *env,
> -					 struct input_dev *dev)
> +					 const struct input_dev *dev)
>  {
>  	int len;
>  
> @@ -1676,9 +1676,9 @@ static int input_add_uevent_modalias_var(struct kobj_uevent_env *env,
>  			return err;					\
>  	} while (0)
>  
> -static int input_dev_uevent(struct device *device, struct kobj_uevent_env *env)
> +static int input_dev_uevent(const struct device *device, struct kobj_uevent_env *env)
>  {
> -	struct input_dev *dev = to_input_dev(device);
> +	const struct input_dev *dev = to_input_dev(device);
>  
>  	INPUT_ADD_HOTPLUG_VAR("PRODUCT=%x/%x/%x/%x",
>  				dev->id.bustype, dev->id.vendor,
> diff --git a/drivers/media/rc/rc-main.c b/drivers/media/rc/rc-main.c
> index 527d9324742b..6bdad6341844 100644
> --- a/drivers/media/rc/rc-main.c
> +++ b/drivers/media/rc/rc-main.c
> @@ -1614,7 +1614,7 @@ static void rc_dev_release(struct device *device)
>  	kfree(dev);
>  }
>  
> -static int rc_dev_uevent(struct device *device, struct kobj_uevent_env *env)
> +static int rc_dev_uevent(const struct device *device, struct kobj_uevent_env *env)
>  {
>  	struct rc_dev *dev = to_rc_dev(device);
>  	int ret = 0;
> diff --git a/drivers/of/device.c b/drivers/of/device.c
> index c674a13c3055..dda51b7ce597 100644
> --- a/drivers/of/device.c
> +++ b/drivers/of/device.c
> @@ -248,7 +248,7 @@ const void *of_device_get_match_data(const struct device *dev)
>  }
>  EXPORT_SYMBOL(of_device_get_match_data);
>  
> -static ssize_t of_device_get_modalias(struct device *dev, char *str, ssize_t len)
> +static ssize_t of_device_get_modalias(const struct device *dev, char *str, ssize_t len)
>  {
>  	const char *compat;
>  	char *c;
> @@ -372,7 +372,7 @@ void of_device_uevent(const struct device *dev, struct kobj_uevent_env *env)
>  	mutex_unlock(&of_mutex);
>  }
>  
> -int of_device_uevent_modalias(struct device *dev, struct kobj_uevent_env *env)
> +int of_device_uevent_modalias(const struct device *dev, struct kobj_uevent_env *env)
>  {
>  	int sl;
>  
> diff --git a/drivers/platform/surface/aggregator/bus.c b/drivers/platform/surface/aggregator/bus.c
> index de539938896e..407eb55050a6 100644
> --- a/drivers/platform/surface/aggregator/bus.c
> +++ b/drivers/platform/surface/aggregator/bus.c
> @@ -35,9 +35,9 @@ static struct attribute *ssam_device_attrs[] = {
>  };
>  ATTRIBUTE_GROUPS(ssam_device);
>  
> -static int ssam_device_uevent(struct device *dev, struct kobj_uevent_env *env)
> +static int ssam_device_uevent(const struct device *dev, struct kobj_uevent_env *env)
>  {
> -	struct ssam_device *sdev = to_ssam_device(dev);
> +	const struct ssam_device *sdev = to_ssam_device(dev);
>  
>  	return add_uevent_var(env, "MODALIAS=ssam:d%02Xc%02Xt%02Xi%02Xf%02X",
>  			      sdev->uid.domain, sdev->uid.category,
> diff --git a/drivers/soundwire/bus_type.c b/drivers/soundwire/bus_type.c
> index 04b3529f8929..26c9a0a85d49 100644
> --- a/drivers/soundwire/bus_type.c
> +++ b/drivers/soundwire/bus_type.c
> @@ -58,9 +58,9 @@ int sdw_slave_modalias(const struct sdw_slave *slave, char *buf, size_t size)
>  			slave->id.sdw_version, slave->id.class_id);
>  }
>  
> -int sdw_slave_uevent(struct device *dev, struct kobj_uevent_env *env)
> +int sdw_slave_uevent(const struct device *dev, struct kobj_uevent_env *env)
>  {
> -	struct sdw_slave *slave = dev_to_sdw_dev(dev);
> +	const struct sdw_slave *slave = dev_to_sdw_dev(dev);
>  	char modalias[32];
>  
>  	sdw_slave_modalias(slave, modalias, sizeof(modalias));
> diff --git a/drivers/thunderbolt/switch.c b/drivers/thunderbolt/switch.c
> index 60da5c23ccaf..2f4ef156b210 100644
> --- a/drivers/thunderbolt/switch.c
> +++ b/drivers/thunderbolt/switch.c
> @@ -2175,9 +2175,9 @@ static void tb_switch_release(struct device *dev)
>  	kfree(sw);
>  }
>  
> -static int tb_switch_uevent(struct device *dev, struct kobj_uevent_env *env)
> +static int tb_switch_uevent(const struct device *dev, struct kobj_uevent_env *env)
>  {
> -	struct tb_switch *sw = tb_to_switch(dev);
> +	const struct tb_switch *sw = tb_to_switch(dev);
>  	const char *type;
>  
>  	if (sw->config.thunderbolt_version == USB4_VERSION_1_0) {
> diff --git a/drivers/thunderbolt/tb.h b/drivers/thunderbolt/tb.h
> index f9786976f5ec..909da0a98134 100644
> --- a/drivers/thunderbolt/tb.h
> +++ b/drivers/thunderbolt/tb.h
> @@ -815,7 +815,7 @@ static inline bool tb_is_switch(const struct device *dev)
>  	return dev->type == &tb_switch_type;
>  }
>  
> -static inline struct tb_switch *tb_to_switch(struct device *dev)
> +static inline struct tb_switch *tb_to_switch(const struct device *dev)
>  {
>  	if (tb_is_switch(dev))
>  		return container_of(dev, struct tb_switch, dev);
> diff --git a/drivers/thunderbolt/xdomain.c b/drivers/thunderbolt/xdomain.c
> index f00b2f62d8e3..aeb40a384bea 100644
> --- a/drivers/thunderbolt/xdomain.c
> +++ b/drivers/thunderbolt/xdomain.c
> @@ -881,7 +881,7 @@ static ssize_t key_show(struct device *dev, struct device_attribute *attr,
>  }
>  static DEVICE_ATTR_RO(key);
>  
> -static int get_modalias(struct tb_service *svc, char *buf, size_t size)
> +static int get_modalias(const struct tb_service *svc, char *buf, size_t size)
>  {
>  	return snprintf(buf, size, "tbsvc:k%sp%08Xv%08Xr%08X", svc->key,
>  			svc->prtcid, svc->prtcvers, svc->prtcrevs);
> @@ -953,9 +953,9 @@ static const struct attribute_group *tb_service_attr_groups[] = {
>  	NULL,
>  };
>  
> -static int tb_service_uevent(struct device *dev, struct kobj_uevent_env *env)
> +static int tb_service_uevent(const struct device *dev, struct kobj_uevent_env *env)
>  {
> -	struct tb_service *svc = container_of(dev, struct tb_service, dev);
> +	const struct tb_service *svc = container_of(dev, struct tb_service, dev);
>  	char modalias[64];
>  
>  	get_modalias(svc, modalias, sizeof(modalias));
> diff --git a/drivers/tty/serdev/core.c b/drivers/tty/serdev/core.c
> index 0180e1e4e75d..aa80de3a8194 100644
> --- a/drivers/tty/serdev/core.c
> +++ b/drivers/tty/serdev/core.c
> @@ -42,7 +42,7 @@ static struct attribute *serdev_device_attrs[] = {
>  };
>  ATTRIBUTE_GROUPS(serdev_device);
>  
> -static int serdev_device_uevent(struct device *dev, struct kobj_uevent_env *env)
> +static int serdev_device_uevent(const struct device *dev, struct kobj_uevent_env *env)
>  {
>  	int rc;
>  
> diff --git a/drivers/usb/core/message.c b/drivers/usb/core/message.c
> index 4d59d927ae3e..c397574a6570 100644
> --- a/drivers/usb/core/message.c
> +++ b/drivers/usb/core/message.c
> @@ -1818,11 +1818,11 @@ void usb_authorize_interface(struct usb_interface *intf)
>  	}
>  }
>  
> -static int usb_if_uevent(struct device *dev, struct kobj_uevent_env *env)
> +static int usb_if_uevent(const struct device *dev, struct kobj_uevent_env *env)
>  {
> -	struct usb_device *usb_dev;
> -	struct usb_interface *intf;
> -	struct usb_host_interface *alt;
> +	const struct usb_device *usb_dev;
> +	const struct usb_interface *intf;
> +	const struct usb_host_interface *alt;
>  
>  	intf = to_usb_interface(dev);
>  	usb_dev = interface_to_usbdev(intf);
> diff --git a/drivers/usb/core/usb.c b/drivers/usb/core/usb.c
> index 11b15d7b357a..8527c06b65e6 100644
> --- a/drivers/usb/core/usb.c
> +++ b/drivers/usb/core/usb.c
> @@ -423,9 +423,9 @@ static void usb_release_dev(struct device *dev)
>  	kfree(udev);
>  }
>  
> -static int usb_dev_uevent(struct device *dev, struct kobj_uevent_env *env)
> +static int usb_dev_uevent(const struct device *dev, struct kobj_uevent_env *env)
>  {
> -	struct usb_device *usb_dev;
> +	const struct usb_device *usb_dev;
>  
>  	usb_dev = to_usb_device(dev);
>  
> diff --git a/drivers/usb/phy/phy.c b/drivers/usb/phy/phy.c
> index 1b24492bb4e5..4b468bde19cf 100644
> --- a/drivers/usb/phy/phy.c
> +++ b/drivers/usb/phy/phy.c
> @@ -80,7 +80,7 @@ static struct usb_phy *__of_usb_find_phy(struct device_node *node)
>  	return ERR_PTR(-EPROBE_DEFER);
>  }
>  
> -static struct usb_phy *__device_to_usb_phy(struct device *dev)
> +static struct usb_phy *__device_to_usb_phy(const struct device *dev)
>  {
>  	struct usb_phy *usb_phy;
>  
> @@ -145,9 +145,9 @@ static void usb_phy_notify_charger_work(struct work_struct *work)
>  	kobject_uevent(&usb_phy->dev->kobj, KOBJ_CHANGE);
>  }
>  
> -static int usb_phy_uevent(struct device *dev, struct kobj_uevent_env *env)
> +static int usb_phy_uevent(const struct device *dev, struct kobj_uevent_env *env)
>  {
> -	struct usb_phy *usb_phy;
> +	const struct usb_phy *usb_phy;
>  	char uchger_state[50] = { 0 };
>  	char uchger_type[50] = { 0 };
>  	unsigned long flags;
> diff --git a/drivers/usb/roles/class.c b/drivers/usb/roles/class.c
> index a3575a5a18ce..3708fb70b693 100644
> --- a/drivers/usb/roles/class.c
> +++ b/drivers/usb/roles/class.c
> @@ -271,8 +271,7 @@ static const struct attribute_group *usb_role_switch_groups[] = {
>  	NULL,
>  };
>  
> -static int
> -usb_role_switch_uevent(struct device *dev, struct kobj_uevent_env *env)
> +static int usb_role_switch_uevent(const struct device *dev, struct kobj_uevent_env *env)
>  {
>  	int ret;
>  
> diff --git a/drivers/usb/typec/class.c b/drivers/usb/typec/class.c
> index bd5e5dd70431..8e2b2077f262 100644
> --- a/drivers/usb/typec/class.c
> +++ b/drivers/usb/typec/class.c
> @@ -1718,7 +1718,7 @@ static const struct attribute_group *typec_groups[] = {
>  	NULL
>  };
>  
> -static int typec_uevent(struct device *dev, struct kobj_uevent_env *env)
> +static int typec_uevent(const struct device *dev, struct kobj_uevent_env *env)
>  {
>  	int ret;
>  
> diff --git a/include/linux/acpi.h b/include/linux/acpi.h
> index 3015235d65e3..fc956c3f8324 100644
> --- a/include/linux/acpi.h
> +++ b/include/linux/acpi.h
> @@ -722,7 +722,7 @@ const struct acpi_device_id *acpi_match_device(const struct acpi_device_id *ids,
>  const void *acpi_device_get_match_data(const struct device *dev);
>  extern bool acpi_driver_match_device(struct device *dev,
>  				     const struct device_driver *drv);
> -int acpi_device_uevent_modalias(struct device *, struct kobj_uevent_env *);
> +int acpi_device_uevent_modalias(const struct device *, struct kobj_uevent_env *);
>  int acpi_device_modalias(struct device *, char *, int);
>  
>  struct platform_device *acpi_create_platform_device(struct acpi_device *,
> @@ -957,7 +957,7 @@ static inline union acpi_object *acpi_evaluate_dsm(acpi_handle handle,
>  	return NULL;
>  }
>  
> -static inline int acpi_device_uevent_modalias(struct device *dev,
> +static inline int acpi_device_uevent_modalias(const struct device *dev,
>  				struct kobj_uevent_env *env)
>  {
>  	return -ENODEV;
> diff --git a/include/linux/device.h b/include/linux/device.h
> index 84ae52de6746..46093bae6905 100644
> --- a/include/linux/device.h
> +++ b/include/linux/device.h
> @@ -88,7 +88,7 @@ int subsys_virtual_register(struct bus_type *subsys,
>  struct device_type {
>  	const char *name;
>  	const struct attribute_group **groups;
> -	int (*uevent)(struct device *dev, struct kobj_uevent_env *env);
> +	int (*uevent)(const struct device *dev, struct kobj_uevent_env *env);
>  	char *(*devnode)(struct device *dev, umode_t *mode,
>  			 kuid_t *uid, kgid_t *gid);
>  	void (*release)(struct device *dev);
> diff --git a/include/linux/firewire.h b/include/linux/firewire.h
> index 980019053e54..4c882d57df02 100644
> --- a/include/linux/firewire.h
> +++ b/include/linux/firewire.h
> @@ -208,7 +208,7 @@ struct fw_device {
>  	struct fw_attribute_group attribute_group;
>  };
>  
> -static inline struct fw_device *fw_device(struct device *dev)
> +static inline struct fw_device *fw_device(const struct device *dev)
>  {
>  	return container_of(dev, struct fw_device, device);
>  }
> @@ -229,7 +229,7 @@ struct fw_unit {
>  	struct fw_attribute_group attribute_group;
>  };
>  
> -static inline struct fw_unit *fw_unit(struct device *dev)
> +static inline struct fw_unit *fw_unit(const struct device *dev)
>  {
>  	return container_of(dev, struct fw_unit, device);
>  }
> @@ -246,7 +246,7 @@ static inline void fw_unit_put(struct fw_unit *unit)
>  	put_device(&unit->device);
>  }
>  
> -static inline struct fw_device *fw_parent_device(struct fw_unit *unit)
> +static inline struct fw_device *fw_parent_device(const struct fw_unit *unit)
>  {
>  	return fw_device(unit->device.parent);
>  }
> diff --git a/include/linux/i3c/device.h b/include/linux/i3c/device.h
> index 8242e13e7b0b..cda61c1d6d60 100644
> --- a/include/linux/i3c/device.h
> +++ b/include/linux/i3c/device.h
> @@ -186,7 +186,7 @@ static inline struct i3c_driver *drv_to_i3cdrv(struct device_driver *drv)
>  }
>  
>  struct device *i3cdev_to_dev(struct i3c_device *i3cdev);
> -struct i3c_device *dev_to_i3cdev(struct device *dev);
> +struct i3c_device *dev_to_i3cdev(const struct device *dev);
>  
>  const struct i3c_device_id *
>  i3c_device_match_id(struct i3c_device *i3cdev,
> @@ -293,7 +293,7 @@ int i3c_device_do_priv_xfers(struct i3c_device *dev,
>  			     struct i3c_priv_xfer *xfers,
>  			     int nxfers);
>  
> -void i3c_device_get_info(struct i3c_device *dev, struct i3c_device_info *info);
> +void i3c_device_get_info(const struct i3c_device *dev, struct i3c_device_info *info);
>  
>  struct i3c_ibi_payload {
>  	unsigned int len;
> diff --git a/include/linux/of_device.h b/include/linux/of_device.h
> index ab7d557d541d..f4b57614979d 100644
> --- a/include/linux/of_device.h
> +++ b/include/linux/of_device.h
> @@ -36,7 +36,7 @@ extern ssize_t of_device_modalias(struct device *dev, char *str, ssize_t len);
>  extern int of_device_request_module(struct device *dev);
>  
>  extern void of_device_uevent(const struct device *dev, struct kobj_uevent_env *env);
> -extern int of_device_uevent_modalias(struct device *dev, struct kobj_uevent_env *env);
> +extern int of_device_uevent_modalias(const struct device *dev, struct kobj_uevent_env *env);
>  
>  static inline struct device_node *of_cpu_device_node_get(int cpu)
>  {
> @@ -83,7 +83,7 @@ static inline int of_device_request_module(struct device *dev)
>  	return -ENODEV;
>  }
>  
> -static inline int of_device_uevent_modalias(struct device *dev,
> +static inline int of_device_uevent_modalias(const struct device *dev,
>  				   struct kobj_uevent_env *env)
>  {
>  	return -ENODEV;
> diff --git a/include/linux/soundwire/sdw_type.h b/include/linux/soundwire/sdw_type.h
> index 52eb66cd11bc..d8c27f1e5559 100644
> --- a/include/linux/soundwire/sdw_type.h
> +++ b/include/linux/soundwire/sdw_type.h
> @@ -21,7 +21,7 @@ static inline int is_sdw_slave(const struct device *dev)
>  int __sdw_register_driver(struct sdw_driver *drv, struct module *owner);
>  void sdw_unregister_driver(struct sdw_driver *drv);
>  
> -int sdw_slave_uevent(struct device *dev, struct kobj_uevent_env *env);
> +int sdw_slave_uevent(const struct device *dev, struct kobj_uevent_env *env);
>  
>  /**
>   * module_sdw_driver() - Helper macro for registering a Soundwire driver
> diff --git a/include/linux/surface_aggregator/device.h b/include/linux/surface_aggregator/device.h
> index 46c45d1b6368..a5dff729edb7 100644
> --- a/include/linux/surface_aggregator/device.h
> +++ b/include/linux/surface_aggregator/device.h
> @@ -229,7 +229,7 @@ static inline bool is_ssam_device(struct device *d)
>   * Return: Returns a pointer to the &struct ssam_device wrapping the given
>   * device @d.
>   */
> -static inline struct ssam_device *to_ssam_device(struct device *d)
> +static inline struct ssam_device *to_ssam_device(const struct device *d)
>  {
>  	return container_of(d, struct ssam_device, dev);
>  }

Greg Kroah-Hartman Dec. 1, 2022, 6:43 p.m. UTC | #22

On Wed, Nov 23, 2022 at 06:00:23PM +0000, Matthew Wilcox wrote:
> On Wed, Nov 23, 2022 at 01:55:42PM -0400, Jason Gunthorpe wrote:
> > On Wed, Nov 23, 2022 at 05:49:36PM +0000, Matthew Wilcox wrote:
> > > On Wed, Nov 23, 2022 at 01:29:56PM -0400, Jason Gunthorpe wrote:
> > > > #define generic_container_of(in_type, in, out_type, out_member) \
> > > > 	_Generic(in,                                        \
> > > >                   const in_type *: ((const out_type *)container_of(in, out_type, out_member)),   \
> > > >                   in_type *: ((out_type *)container_of(in, out_type, out_member)) \
> > > > 		  )
> > > 
> > > There's a neat trick I found in seqlock.h:
> > > 
> > > #define generic_container_of(in_t, in, out_t, m)			\
> > > 	_Generic(*(in),							\
> > > 		const in_t: ((const out_t *)container_of(in, out_t, m)), \
> > > 		in_t: ((out_t *)container_of(in, out_type, m))	\
> > > 	)
> > >
> > > and now it fits in 80 columns ;-)
> > 
> > Aside from less letters, is their another benifit to using *(in) ?
> 
> I don't think so.  It just looks nicer to me than putting the star in
> each case.  If I'd thought of it, I would have done it to page_folio(),
> but I won't change it now.

Ah, but your trick will not work, that blows up and will not build.  The
original one from Jason here does work.  _Generic is tricky...

thanks,

greg k-h

Greg Kroah-Hartman Jan. 11, 2023, 9:51 a.m. UTC | #23

On Wed, Nov 23, 2022 at 01:38:05PM +0100, Rafael J. Wysocki wrote:
> On Wed, Nov 23, 2022 at 1:25 PM Greg Kroah-Hartman
> <[e-mail]> wrote:
> >
> > The uevent() callback in struct device_type should not be modifying the
> > device that is passed into it, so mark it as a const * and propagate the
> > function signature changes out into all relevant subsystems that use
> > this callback.
> >
> > Cc: Jens Axboe <[e-mail]>
> > Cc: "Rafael J. Wysocki" <[e-mail]>
> > Cc: Len Brown <[e-mail]>
> > Cc: Stefan Richter <[e-mail]>
> > Cc: Wolfram Sang <[e-mail]>
> > Cc: Alexandre Belloni <[e-mail]>
> > Cc: Dmitry Torokhov <[e-mail]>
> > Cc: Sean Young <[e-mail]>
> > Cc: Mauro Carvalho Chehab <[e-mail]>
> > Cc: Rob Herring <[e-mail]>
> > Cc: Frank Rowand <[e-mail]>
> > Cc: Maximilian Luz <[e-mail]>
> > Cc: Hans de Goede <[e-mail]>
> > Cc: Mark Gross <[e-mail]>
> > Cc: Vinod Koul <[e-mail]>
> > Cc: Bard Liao <[e-mail]>
> > Cc: Pierre-Louis Bossart <[e-mail]>
> > Cc: Sanyog Kale <[e-mail]>
> > Cc: Andreas Noever <[e-mail]>
> > Cc: Michael Jamet <[e-mail]>
> > Cc: Mika Westerberg <[e-mail]>
> > Cc: Yehezkel Bernat <[e-mail]>
> > Cc: Jiri Slaby <[e-mail]>
> > Cc: Heikki Krogerus <[e-mail]>
> > Cc: "Matthew Wilcox (Oracle)" <[e-mail]>
> > Cc: "Martin K. Petersen" <[e-mail]>
> > Cc: Chaitanya Kulkarni <[e-mail]>
> > Cc: Ming Lei <[e-mail]>
> > Cc: Jilin Yuan <[e-mail]>
> > Cc: Alan Stern <[e-mail]>
> > Cc: Andy Shevchenko <[e-mail]>
> > Cc: Sakari Ailus <[e-mail]>
> > Cc: Jason Gunthorpe <[e-mail]>
> > Cc: Thomas Gleixner <[e-mail]>
> > Cc: Ira Weiny <[e-mail]>
> > Cc: Dan Williams <[e-mail]>
> > Cc: Won Chung <[e-mail]>
> > Cc: [e-mail]
> > Cc: [e-mail]
> > Cc: [e-mail]
> > Cc: [e-mail]
> > Cc: [e-mail]
> > Cc: [e-mail]
> > Cc: [e-mail]
> > Cc: [e-mail]
> > Cc: [e-mail]
> > Cc: [e-mail]
> > Cc: [e-mail]
> > Cc: [e-mail]
> > Cc: [e-mail]
> > Signed-off-by: Greg Kroah-Hartman <[e-mail]>
> 
> Acked-by: Rafael J. Wysocki <[e-mail]>
> 
> (which my ACPI maintainer hat on).

thanks for the review, I'll add it to the v2 patch.

greg k-h

Greg Kroah-Hartman Jan. 11, 2023, 9:52 a.m. UTC | #24

On Fri, Nov 25, 2022 at 11:56:18AM +0000, Mauro Carvalho Chehab wrote:
> Em Wed, 23 Nov 2022 13:25:21 +0100
> Greg Kroah-Hartman <[e-mail]> escreveu:
> 
> > The uevent() callback in struct device_type should not be modifying the
> > device that is passed into it, so mark it as a const * and propagate the
> > function signature changes out into all relevant subsystems that use
> > this callback.
> 
> Acked-by: Mauro Carvalho Chehab <[e-mail]>

Thanks for the review.

Greg Kroah-Hartman Jan. 11, 2023, 9:52 a.m. UTC | #25

On Wed, Nov 23, 2022 at 03:56:54PM +0200, Mika Westerberg wrote:
> On Wed, Nov 23, 2022 at 01:25:21PM +0100, Greg Kroah-Hartman wrote:
> > The uevent() callback in struct device_type should not be modifying the
> > device that is passed into it, so mark it as a const * and propagate the
> > function signature changes out into all relevant subsystems that use
> > this callback.
> > 
> > Cc: Jens Axboe <[e-mail]>
> > Cc: "Rafael J. Wysocki" <[e-mail]>
> > Cc: Len Brown <[e-mail]>
> > Cc: Stefan Richter <[e-mail]>
> > Cc: Wolfram Sang <[e-mail]>
> > Cc: Alexandre Belloni <[e-mail]>
> > Cc: Dmitry Torokhov <[e-mail]>
> > Cc: Sean Young <[e-mail]>
> > Cc: Mauro Carvalho Chehab <[e-mail]>
> > Cc: Rob Herring <[e-mail]>
> > Cc: Frank Rowand <[e-mail]>
> > Cc: Maximilian Luz <[e-mail]>
> > Cc: Hans de Goede <[e-mail]>
> > Cc: Mark Gross <[e-mail]>
> > Cc: Vinod Koul <[e-mail]>
> > Cc: Bard Liao <[e-mail]>
> > Cc: Pierre-Louis Bossart <[e-mail]>
> > Cc: Sanyog Kale <[e-mail]>
> > Cc: Andreas Noever <[e-mail]>
> > Cc: Michael Jamet <[e-mail]>
> > Cc: Mika Westerberg <[e-mail]>
> 
> Acked-by: Mika Westerberg <[e-mail]> # for Thunderbolt

Thanks for the review.

Patch

diff --git a/block/partitions/core.c b/block/partitions/core.c
index b8112f52d388..7b8ef6296abd 100644
--- a/block/partitions/core.c
+++ b/block/partitions/core.c
@@ -254,9 +254,9 @@  static void part_release(struct device *dev)
 	iput(dev_to_bdev(dev)->bd_inode);
 }
 
-static int part_uevent(struct device *dev, struct kobj_uevent_env *env)
+static int part_uevent(const struct device *dev, struct kobj_uevent_env *env)
 {
-	struct block_device *part = dev_to_bdev(dev);
+	const struct block_device *part = dev_to_bdev(dev);
 
 	add_uevent_var(env, "PARTN=%u", part->bd_partno);
 	if (part->bd_meta_info && part->bd_meta_info->volname[0])
diff --git a/drivers/acpi/device_sysfs.c b/drivers/acpi/device_sysfs.c
index 120873dad2cc..daff2c0c5c52 100644
--- a/drivers/acpi/device_sysfs.c
+++ b/drivers/acpi/device_sysfs.c
@@ -133,7 +133,7 @@  static void acpi_hide_nondev_subnodes(struct acpi_device_data *data)
  *         -EINVAL: output error
  *         -ENOMEM: output is truncated
  */
-static int create_pnp_modalias(struct acpi_device *acpi_dev, char *modalias,
+static int create_pnp_modalias(const struct acpi_device *acpi_dev, char *modalias,
 			       int size)
 {
 	int len;
@@ -191,7 +191,7 @@  static int create_pnp_modalias(struct acpi_device *acpi_dev, char *modalias,
  * only be called for devices having ACPI_DT_NAMESPACE_HID in their list of
  * ACPI/PNP IDs.
  */
-static int create_of_modalias(struct acpi_device *acpi_dev, char *modalias,
+static int create_of_modalias(const struct acpi_device *acpi_dev, char *modalias,
 			      int size)
 {
 	struct acpi_buffer buf = { ACPI_ALLOCATE_BUFFER };
@@ -239,7 +239,7 @@  static int create_of_modalias(struct acpi_device *acpi_dev, char *modalias,
 	return len;
 }
 
-int __acpi_device_uevent_modalias(struct acpi_device *adev,
+int __acpi_device_uevent_modalias(const struct acpi_device *adev,
 				  struct kobj_uevent_env *env)
 {
 	int len;
@@ -277,7 +277,7 @@  int __acpi_device_uevent_modalias(struct acpi_device *adev,
  * Because other buses do not support ACPI HIDs & CIDs, e.g. for a device with
  * hid:IBM0001 and cid:ACPI0001 you get: "acpi:IBM0001:ACPI0001".
  */
-int acpi_device_uevent_modalias(struct device *dev, struct kobj_uevent_env *env)
+int acpi_device_uevent_modalias(const struct device *dev, struct kobj_uevent_env *env)
 {
 	return __acpi_device_uevent_modalias(acpi_companion_match(dev), env);
 }
diff --git a/drivers/acpi/internal.h b/drivers/acpi/internal.h
index 219c02df9a08..d422884eb3d0 100644
--- a/drivers/acpi/internal.h
+++ b/drivers/acpi/internal.h
@@ -120,7 +120,7 @@  int acpi_bus_register_early_device(int type);
                      Device Matching and Notification
    -------------------------------------------------------------------------- */
 struct acpi_device *acpi_companion_match(const struct device *dev);
-int __acpi_device_uevent_modalias(struct acpi_device *adev,
+int __acpi_device_uevent_modalias(const struct acpi_device *adev,
 				  struct kobj_uevent_env *env);
 
 /* --------------------------------------------------------------------------
diff --git a/drivers/firewire/core-device.c b/drivers/firewire/core-device.c
index adddd8c45d0c..aa597cda0d88 100644
--- a/drivers/firewire/core-device.c
+++ b/drivers/firewire/core-device.c
@@ -133,7 +133,7 @@  static void get_ids(const u32 *directory, int *id)
 	}
 }
 
-static void get_modalias_ids(struct fw_unit *unit, int *id)
+static void get_modalias_ids(const struct fw_unit *unit, int *id)
 {
 	get_ids(&fw_parent_device(unit)->config_rom[5], id);
 	get_ids(unit->directory, id);
@@ -195,7 +195,7 @@  static void fw_unit_remove(struct device *dev)
 	driver->remove(fw_unit(dev));
 }
 
-static int get_modalias(struct fw_unit *unit, char *buffer, size_t buffer_size)
+static int get_modalias(const struct fw_unit *unit, char *buffer, size_t buffer_size)
 {
 	int id[] = {0, 0, 0, 0};
 
@@ -206,9 +206,9 @@  static int get_modalias(struct fw_unit *unit, char *buffer, size_t buffer_size)
 			id[0], id[1], id[2], id[3]);
 }
 
-static int fw_unit_uevent(struct device *dev, struct kobj_uevent_env *env)
+static int fw_unit_uevent(const struct device *dev, struct kobj_uevent_env *env)
 {
-	struct fw_unit *unit = fw_unit(dev);
+	const struct fw_unit *unit = fw_unit(dev);
 	char modalias[64];
 
 	get_modalias(unit, modalias, sizeof(modalias));
diff --git a/drivers/i2c/i2c-core-base.c b/drivers/i2c/i2c-core-base.c
index b4edf10e8fd0..fb16e33e52c6 100644
--- a/drivers/i2c/i2c-core-base.c
+++ b/drivers/i2c/i2c-core-base.c
@@ -136,9 +136,9 @@  static int i2c_device_match(struct device *dev, struct device_driver *drv)
 	return 0;
 }
 
-static int i2c_device_uevent(struct device *dev, struct kobj_uevent_env *env)
+static int i2c_device_uevent(const struct device *dev, struct kobj_uevent_env *env)
 {
-	struct i2c_client *client = to_i2c_client(dev);
+	const struct i2c_client *client = to_i2c_client(dev);
 	int rc;
 
 	rc = of_device_uevent_modalias(dev, env);
diff --git a/drivers/i3c/device.c b/drivers/i3c/device.c
index e92d3e9a52bd..05f8ab762e34 100644
--- a/drivers/i3c/device.c
+++ b/drivers/i3c/device.c
@@ -58,7 +58,7 @@  EXPORT_SYMBOL_GPL(i3c_device_do_priv_xfers);
  *
  * Retrieve I3C dev info.
  */
-void i3c_device_get_info(struct i3c_device *dev,
+void i3c_device_get_info(const struct i3c_device *dev,
 			 struct i3c_device_info *info)
 {
 	if (!info)
@@ -194,7 +194,7 @@  EXPORT_SYMBOL_GPL(i3cdev_to_dev);
  *
  * Return: a pointer to an I3C device object.
  */
-struct i3c_device *dev_to_i3cdev(struct device *dev)
+struct i3c_device *dev_to_i3cdev(const struct device *dev)
 {
 	return container_of(dev, struct i3c_device, dev);
 }
diff --git a/drivers/i3c/master.c b/drivers/i3c/master.c
index 351c81a929a6..bf1a2b2f34c4 100644
--- a/drivers/i3c/master.c
+++ b/drivers/i3c/master.c
@@ -273,9 +273,9 @@  static struct attribute *i3c_device_attrs[] = {
 };
 ATTRIBUTE_GROUPS(i3c_device);
 
-static int i3c_device_uevent(struct device *dev, struct kobj_uevent_env *env)
+static int i3c_device_uevent(const struct device *dev, struct kobj_uevent_env *env)
 {
-	struct i3c_device *i3cdev = dev_to_i3cdev(dev);
+	const struct i3c_device *i3cdev = dev_to_i3cdev(dev);
 	struct i3c_device_info devinfo;
 	u16 manuf, part, ext;
 
diff --git a/drivers/input/input.c b/drivers/input/input.c
index 50597165dc54..a612afffa196 100644
--- a/drivers/input/input.c
+++ b/drivers/input/input.c
@@ -1371,7 +1371,7 @@  INPUT_DEV_STRING_ATTR_SHOW(phys);
 INPUT_DEV_STRING_ATTR_SHOW(uniq);
 
 static int input_print_modalias_bits(char *buf, int size,
-				     char name, unsigned long *bm,
+				     char name, const unsigned long *bm,
 				     unsigned int min_bit, unsigned int max_bit)
 {
 	int len = 0, i;
@@ -1383,7 +1383,7 @@  static int input_print_modalias_bits(char *buf, int size,
 	return len;
 }
 
-static int input_print_modalias(char *buf, int size, struct input_dev *id,
+static int input_print_modalias(char *buf, int size, const struct input_dev *id,
 				int add_cr)
 {
 	int len;
@@ -1431,7 +1431,7 @@  static ssize_t input_dev_show_modalias(struct device *dev,
 }
 static DEVICE_ATTR(modalias, S_IRUGO, input_dev_show_modalias, NULL);
 
-static int input_print_bitmap(char *buf, int buf_size, unsigned long *bitmap,
+static int input_print_bitmap(char *buf, int buf_size, const unsigned long *bitmap,
 			      int max, int add_cr);
 
 static ssize_t input_dev_show_properties(struct device *dev,
@@ -1523,7 +1523,7 @@  static const struct attribute_group input_dev_id_attr_group = {
 	.attrs	= input_dev_id_attrs,
 };
 
-static int input_print_bitmap(char *buf, int buf_size, unsigned long *bitmap,
+static int input_print_bitmap(char *buf, int buf_size, const unsigned long *bitmap,
 			      int max, int add_cr)
 {
 	int i;
@@ -1620,7 +1620,7 @@  static void input_dev_release(struct device *device)
  * device bitfields.
  */
 static int input_add_uevent_bm_var(struct kobj_uevent_env *env,
-				   const char *name, unsigned long *bitmap, int max)
+				   const char *name, const unsigned long *bitmap, int max)
 {
 	int len;
 
@@ -1638,7 +1638,7 @@  static int input_add_uevent_bm_var(struct kobj_uevent_env *env,
 }
 
 static int input_add_uevent_modalias_var(struct kobj_uevent_env *env,
-					 struct input_dev *dev)
+					 const struct input_dev *dev)
 {
 	int len;
 
@@ -1676,9 +1676,9 @@  static int input_add_uevent_modalias_var(struct kobj_uevent_env *env,
 			return err;					\
 	} while (0)
 
-static int input_dev_uevent(struct device *device, struct kobj_uevent_env *env)
+static int input_dev_uevent(const struct device *device, struct kobj_uevent_env *env)
 {
-	struct input_dev *dev = to_input_dev(device);
+	const struct input_dev *dev = to_input_dev(device);
 
 	INPUT_ADD_HOTPLUG_VAR("PRODUCT=%x/%x/%x/%x",
 				dev->id.bustype, dev->id.vendor,
diff --git a/drivers/media/rc/rc-main.c b/drivers/media/rc/rc-main.c
index 527d9324742b..6bdad6341844 100644
--- a/drivers/media/rc/rc-main.c
+++ b/drivers/media/rc/rc-main.c
@@ -1614,7 +1614,7 @@  static void rc_dev_release(struct device *device)
 	kfree(dev);
 }
 
-static int rc_dev_uevent(struct device *device, struct kobj_uevent_env *env)
+static int rc_dev_uevent(const struct device *device, struct kobj_uevent_env *env)
 {
 	struct rc_dev *dev = to_rc_dev(device);
 	int ret = 0;
diff --git a/drivers/of/device.c b/drivers/of/device.c
index c674a13c3055..dda51b7ce597 100644
--- a/drivers/of/device.c
+++ b/drivers/of/device.c
@@ -248,7 +248,7 @@  const void *of_device_get_match_data(const struct device *dev)
 }
 EXPORT_SYMBOL(of_device_get_match_data);
 
-static ssize_t of_device_get_modalias(struct device *dev, char *str, ssize_t len)
+static ssize_t of_device_get_modalias(const struct device *dev, char *str, ssize_t len)
 {
 	const char *compat;
 	char *c;
@@ -372,7 +372,7 @@  void of_device_uevent(const struct device *dev, struct kobj_uevent_env *env)
 	mutex_unlock(&of_mutex);
 }
 
-int of_device_uevent_modalias(struct device *dev, struct kobj_uevent_env *env)
+int of_device_uevent_modalias(const struct device *dev, struct kobj_uevent_env *env)
 {
 	int sl;
 
diff --git a/drivers/platform/surface/aggregator/bus.c b/drivers/platform/surface/aggregator/bus.c
index de539938896e..407eb55050a6 100644
--- a/drivers/platform/surface/aggregator/bus.c
+++ b/drivers/platform/surface/aggregator/bus.c
@@ -35,9 +35,9 @@  static struct attribute *ssam_device_attrs[] = {
 };
 ATTRIBUTE_GROUPS(ssam_device);
 
-static int ssam_device_uevent(struct device *dev, struct kobj_uevent_env *env)
+static int ssam_device_uevent(const struct device *dev, struct kobj_uevent_env *env)
 {
-	struct ssam_device *sdev = to_ssam_device(dev);
+	const struct ssam_device *sdev = to_ssam_device(dev);
 
 	return add_uevent_var(env, "MODALIAS=ssam:d%02Xc%02Xt%02Xi%02Xf%02X",
 			      sdev->uid.domain, sdev->uid.category,
diff --git a/drivers/soundwire/bus_type.c b/drivers/soundwire/bus_type.c
index 04b3529f8929..26c9a0a85d49 100644
--- a/drivers/soundwire/bus_type.c
+++ b/drivers/soundwire/bus_type.c
@@ -58,9 +58,9 @@  int sdw_slave_modalias(const struct sdw_slave *slave, char *buf, size_t size)
 			slave->id.sdw_version, slave->id.class_id);
 }
 
-int sdw_slave_uevent(struct device *dev, struct kobj_uevent_env *env)
+int sdw_slave_uevent(const struct device *dev, struct kobj_uevent_env *env)
 {
-	struct sdw_slave *slave = dev_to_sdw_dev(dev);
+	const struct sdw_slave *slave = dev_to_sdw_dev(dev);
 	char modalias[32];
 
 	sdw_slave_modalias(slave, modalias, sizeof(modalias));
diff --git a/drivers/thunderbolt/switch.c b/drivers/thunderbolt/switch.c
index 60da5c23ccaf..2f4ef156b210 100644
--- a/drivers/thunderbolt/switch.c
+++ b/drivers/thunderbolt/switch.c
@@ -2175,9 +2175,9 @@  static void tb_switch_release(struct device *dev)
 	kfree(sw);
 }
 
-static int tb_switch_uevent(struct device *dev, struct kobj_uevent_env *env)
+static int tb_switch_uevent(const struct device *dev, struct kobj_uevent_env *env)
 {
-	struct tb_switch *sw = tb_to_switch(dev);
+	const struct tb_switch *sw = tb_to_switch(dev);
 	const char *type;
 
 	if (sw->config.thunderbolt_version == USB4_VERSION_1_0) {
diff --git a/drivers/thunderbolt/tb.h b/drivers/thunderbolt/tb.h
index f9786976f5ec..909da0a98134 100644
--- a/drivers/thunderbolt/tb.h
+++ b/drivers/thunderbolt/tb.h
@@ -815,7 +815,7 @@  static inline bool tb_is_switch(const struct device *dev)
 	return dev->type == &tb_switch_type;
 }
 
-static inline struct tb_switch *tb_to_switch(struct device *dev)
+static inline struct tb_switch *tb_to_switch(const struct device *dev)
 {
 	if (tb_is_switch(dev))
 		return container_of(dev, struct tb_switch, dev);
diff --git a/drivers/thunderbolt/xdomain.c b/drivers/thunderbolt/xdomain.c
index f00b2f62d8e3..aeb40a384bea 100644
--- a/drivers/thunderbolt/xdomain.c
+++ b/drivers/thunderbolt/xdomain.c
@@ -881,7 +881,7 @@  static ssize_t key_show(struct device *dev, struct device_attribute *attr,
 }
 static DEVICE_ATTR_RO(key);
 
-static int get_modalias(struct tb_service *svc, char *buf, size_t size)
+static int get_modalias(const struct tb_service *svc, char *buf, size_t size)
 {
 	return snprintf(buf, size, "tbsvc:k%sp%08Xv%08Xr%08X", svc->key,
 			svc->prtcid, svc->prtcvers, svc->prtcrevs);
@@ -953,9 +953,9 @@  static const struct attribute_group *tb_service_attr_groups[] = {
 	NULL,
 };
 
-static int tb_service_uevent(struct device *dev, struct kobj_uevent_env *env)
+static int tb_service_uevent(const struct device *dev, struct kobj_uevent_env *env)
 {
-	struct tb_service *svc = container_of(dev, struct tb_service, dev);
+	const struct tb_service *svc = container_of(dev, struct tb_service, dev);
 	char modalias[64];
 
 	get_modalias(svc, modalias, sizeof(modalias));
diff --git a/drivers/tty/serdev/core.c b/drivers/tty/serdev/core.c
index 0180e1e4e75d..aa80de3a8194 100644
--- a/drivers/tty/serdev/core.c
+++ b/drivers/tty/serdev/core.c
@@ -42,7 +42,7 @@  static struct attribute *serdev_device_attrs[] = {
 };
 ATTRIBUTE_GROUPS(serdev_device);
 
-static int serdev_device_uevent(struct device *dev, struct kobj_uevent_env *env)
+static int serdev_device_uevent(const struct device *dev, struct kobj_uevent_env *env)
 {
 	int rc;
 
diff --git a/drivers/usb/core/message.c b/drivers/usb/core/message.c
index 4d59d927ae3e..c397574a6570 100644
--- a/drivers/usb/core/message.c
+++ b/drivers/usb/core/message.c
@@ -1818,11 +1818,11 @@  void usb_authorize_interface(struct usb_interface *intf)
 	}
 }
 
-static int usb_if_uevent(struct device *dev, struct kobj_uevent_env *env)
+static int usb_if_uevent(const struct device *dev, struct kobj_uevent_env *env)
 {
-	struct usb_device *usb_dev;
-	struct usb_interface *intf;
-	struct usb_host_interface *alt;
+	const struct usb_device *usb_dev;
+	const struct usb_interface *intf;
+	const struct usb_host_interface *alt;
 
 	intf = to_usb_interface(dev);
 	usb_dev = interface_to_usbdev(intf);
diff --git a/drivers/usb/core/usb.c b/drivers/usb/core/usb.c
index 11b15d7b357a..8527c06b65e6 100644
--- a/drivers/usb/core/usb.c
+++ b/drivers/usb/core/usb.c
@@ -423,9 +423,9 @@  static void usb_release_dev(struct device *dev)
 	kfree(udev);
 }
 
-static int usb_dev_uevent(struct device *dev, struct kobj_uevent_env *env)
+static int usb_dev_uevent(const struct device *dev, struct kobj_uevent_env *env)
 {
-	struct usb_device *usb_dev;
+	const struct usb_device *usb_dev;
 
 	usb_dev = to_usb_device(dev);
 
diff --git a/drivers/usb/phy/phy.c b/drivers/usb/phy/phy.c
index 1b24492bb4e5..4b468bde19cf 100644
--- a/drivers/usb/phy/phy.c
+++ b/drivers/usb/phy/phy.c
@@ -80,7 +80,7 @@  static struct usb_phy *__of_usb_find_phy(struct device_node *node)
 	return ERR_PTR(-EPROBE_DEFER);
 }
 
-static struct usb_phy *__device_to_usb_phy(struct device *dev)
+static struct usb_phy *__device_to_usb_phy(const struct device *dev)
 {
 	struct usb_phy *usb_phy;
 
@@ -145,9 +145,9 @@  static void usb_phy_notify_charger_work(struct work_struct *work)
 	kobject_uevent(&usb_phy->dev->kobj, KOBJ_CHANGE);
 }
 
-static int usb_phy_uevent(struct device *dev, struct kobj_uevent_env *env)
+static int usb_phy_uevent(const struct device *dev, struct kobj_uevent_env *env)
 {
-	struct usb_phy *usb_phy;
+	const struct usb_phy *usb_phy;
 	char uchger_state[50] = { 0 };
 	char uchger_type[50] = { 0 };
 	unsigned long flags;
diff --git a/drivers/usb/roles/class.c b/drivers/usb/roles/class.c
index a3575a5a18ce..3708fb70b693 100644
--- a/drivers/usb/roles/class.c
+++ b/drivers/usb/roles/class.c
@@ -271,8 +271,7 @@  static const struct attribute_group *usb_role_switch_groups[] = {
 	NULL,
 };
 
-static int
-usb_role_switch_uevent(struct device *dev, struct kobj_uevent_env *env)
+static int usb_role_switch_uevent(const struct device *dev, struct kobj_uevent_env *env)
 {
 	int ret;
 
diff --git a/drivers/usb/typec/class.c b/drivers/usb/typec/class.c
index bd5e5dd70431..8e2b2077f262 100644
--- a/drivers/usb/typec/class.c
+++ b/drivers/usb/typec/class.c
@@ -1718,7 +1718,7 @@  static const struct attribute_group *typec_groups[] = {
 	NULL
 };
 
-static int typec_uevent(struct device *dev, struct kobj_uevent_env *env)
+static int typec_uevent(const struct device *dev, struct kobj_uevent_env *env)
 {
 	int ret;
 
diff --git a/include/linux/acpi.h b/include/linux/acpi.h
index 3015235d65e3..fc956c3f8324 100644
--- a/include/linux/acpi.h
+++ b/include/linux/acpi.h
@@ -722,7 +722,7 @@  const struct acpi_device_id *acpi_match_device(const struct acpi_device_id *ids,
 const void *acpi_device_get_match_data(const struct device *dev);
 extern bool acpi_driver_match_device(struct device *dev,
 				     const struct device_driver *drv);
-int acpi_device_uevent_modalias(struct device *, struct kobj_uevent_env *);
+int acpi_device_uevent_modalias(const struct device *, struct kobj_uevent_env *);
 int acpi_device_modalias(struct device *, char *, int);
 
 struct platform_device *acpi_create_platform_device(struct acpi_device *,
@@ -957,7 +957,7 @@  static inline union acpi_object *acpi_evaluate_dsm(acpi_handle handle,
 	return NULL;
 }
 
-static inline int acpi_device_uevent_modalias(struct device *dev,
+static inline int acpi_device_uevent_modalias(const struct device *dev,
 				struct kobj_uevent_env *env)
 {
 	return -ENODEV;
diff --git a/include/linux/device.h b/include/linux/device.h
index 84ae52de6746..46093bae6905 100644
--- a/include/linux/device.h
+++ b/include/linux/device.h
@@ -88,7 +88,7 @@  int subsys_virtual_register(struct bus_type *subsys,
 struct device_type {
 	const char *name;
 	const struct attribute_group **groups;
-	int (*uevent)(struct device *dev, struct kobj_uevent_env *env);
+	int (*uevent)(const struct device *dev, struct kobj_uevent_env *env);
 	char *(*devnode)(struct device *dev, umode_t *mode,
 			 kuid_t *uid, kgid_t *gid);
 	void (*release)(struct device *dev);
diff --git a/include/linux/firewire.h b/include/linux/firewire.h
index 980019053e54..4c882d57df02 100644
--- a/include/linux/firewire.h
+++ b/include/linux/firewire.h
@@ -208,7 +208,7 @@  struct fw_device {
 	struct fw_attribute_group attribute_group;
 };
 
-static inline struct fw_device *fw_device(struct device *dev)
+static inline struct fw_device *fw_device(const struct device *dev)
 {
 	return container_of(dev, struct fw_device, device);
 }
@@ -229,7 +229,7 @@  struct fw_unit {
 	struct fw_attribute_group attribute_group;
 };
 
-static inline struct fw_unit *fw_unit(struct device *dev)
+static inline struct fw_unit *fw_unit(const struct device *dev)
 {
 	return container_of(dev, struct fw_unit, device);
 }
@@ -246,7 +246,7 @@  static inline void fw_unit_put(struct fw_unit *unit)
 	put_device(&unit->device);
 }
 
-static inline struct fw_device *fw_parent_device(struct fw_unit *unit)
+static inline struct fw_device *fw_parent_device(const struct fw_unit *unit)
 {
 	return fw_device(unit->device.parent);
 }
diff --git a/include/linux/i3c/device.h b/include/linux/i3c/device.h
index 8242e13e7b0b..cda61c1d6d60 100644
--- a/include/linux/i3c/device.h
+++ b/include/linux/i3c/device.h
@@ -186,7 +186,7 @@  static inline struct i3c_driver *drv_to_i3cdrv(struct device_driver *drv)
 }
 
 struct device *i3cdev_to_dev(struct i3c_device *i3cdev);
-struct i3c_device *dev_to_i3cdev(struct device *dev);
+struct i3c_device *dev_to_i3cdev(const struct device *dev);
 
 const struct i3c_device_id *
 i3c_device_match_id(struct i3c_device *i3cdev,
@@ -293,7 +293,7 @@  int i3c_device_do_priv_xfers(struct i3c_device *dev,
 			     struct i3c_priv_xfer *xfers,
 			     int nxfers);
 
-void i3c_device_get_info(struct i3c_device *dev, struct i3c_device_info *info);
+void i3c_device_get_info(const struct i3c_device *dev, struct i3c_device_info *info);
 
 struct i3c_ibi_payload {
 	unsigned int len;
diff --git a/include/linux/of_device.h b/include/linux/of_device.h
index ab7d557d541d..f4b57614979d 100644
--- a/include/linux/of_device.h
+++ b/include/linux/of_device.h
@@ -36,7 +36,7 @@  extern ssize_t of_device_modalias(struct device *dev, char *str, ssize_t len);
 extern int of_device_request_module(struct device *dev);
 
 extern void of_device_uevent(const struct device *dev, struct kobj_uevent_env *env);
-extern int of_device_uevent_modalias(struct device *dev, struct kobj_uevent_env *env);
+extern int of_device_uevent_modalias(const struct device *dev, struct kobj_uevent_env *env);
 
 static inline struct device_node *of_cpu_device_node_get(int cpu)
 {
@@ -83,7 +83,7 @@  static inline int of_device_request_module(struct device *dev)
 	return -ENODEV;
 }
 
-static inline int of_device_uevent_modalias(struct device *dev,
+static inline int of_device_uevent_modalias(const struct device *dev,
 				   struct kobj_uevent_env *env)
 {
 	return -ENODEV;
diff --git a/include/linux/soundwire/sdw_type.h b/include/linux/soundwire/sdw_type.h
index 52eb66cd11bc..d8c27f1e5559 100644
--- a/include/linux/soundwire/sdw_type.h
+++ b/include/linux/soundwire/sdw_type.h
@@ -21,7 +21,7 @@  static inline int is_sdw_slave(const struct device *dev)
 int __sdw_register_driver(struct sdw_driver *drv, struct module *owner);
 void sdw_unregister_driver(struct sdw_driver *drv);
 
-int sdw_slave_uevent(struct device *dev, struct kobj_uevent_env *env);
+int sdw_slave_uevent(const struct device *dev, struct kobj_uevent_env *env);
 
 /**
  * module_sdw_driver() - Helper macro for registering a Soundwire driver
diff --git a/include/linux/surface_aggregator/device.h b/include/linux/surface_aggregator/device.h
index 46c45d1b6368..a5dff729edb7 100644
--- a/include/linux/surface_aggregator/device.h
+++ b/include/linux/surface_aggregator/device.h
@@ -229,7 +229,7 @@  static inline bool is_ssam_device(struct device *d)
  * Return: Returns a pointer to the &struct ssam_device wrapping the given
  * device @d.
  */
-static inline struct ssam_device *to_ssam_device(struct device *d)
+static inline struct ssam_device *to_ssam_device(const struct device *d)
 {
 	return container_of(d, struct ssam_device, dev);
 }