diff options
| author | Uwe Kleine-König (The Capable Hub) <u.kleine-koenig@baylibre.com> | 2026-05-11 12:45:02 +0200 |
|---|---|---|
| committer | Takashi Sakamoto <o-takashi@sakamocchi.jp> | 2026-05-11 12:45:02 +0200 |
| commit | 39d260d6bc7aab6777c0d14d1e27648ca8e9252e (patch) | |
| tree | ccafd14f8909c359a8904bf14bd9ab2cc1886ecd /include/linux | |
| parent | fcabbf40fae501379b4f3a057febe92d4b0ebdd8 (diff) | |
firewire: Simplify storing pointers in device id struct
Technically it is fine (on all current Linux architectures) to store a
pointer in an unsigned long variable. However this needs explicit
casting which is an easy source for type mismatches.
By replacing the plain unsigned long .driver_data in struct
ieee1394_device_id by an anonymous union, most of the casting can be
dropped. There is still some implicit casting involved (between a void *
and a driver specific pointer type), but that's better than the approach
to store a pointer in an unsigned long variable as this doesn't lose the
information that the data being pointed to is const.
All users of struct ieee1394_device_id are initialized in a way that is
compatible with the new definition, so no adaptions are needed there.
(The comments addressing to CHERI extension are dropped by the
maintainer.)
Signed-off-by: Uwe Kleine-König (The Capable Hub) <u.kleine-koenig@baylibre.com>
Link: https://lore.kernel.org/r/e5ba45a7e386461c0b1a5001635aa008b01c2164.1778494204.git.u.kleine-koenig@baylibre.com
Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Diffstat (limited to 'include/linux')
| -rw-r--r-- | include/linux/mod_devicetable.h | 5 |
1 files changed, 4 insertions, 1 deletions
diff --git a/include/linux/mod_devicetable.h b/include/linux/mod_devicetable.h index 23ff24080dfd..3b0c9a251a2e 100644 --- a/include/linux/mod_devicetable.h +++ b/include/linux/mod_devicetable.h @@ -61,7 +61,10 @@ struct ieee1394_device_id { __u32 model_id; __u32 specifier_id; __u32 version; - kernel_ulong_t driver_data; + union { + kernel_ulong_t driver_data; + const void *driver_data_ptr; + }; }; |