Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit a2f11835 authored by Shawn Landden's avatar Shawn Landden Committed by Marc Kleine-Budde
Browse files

can.h: make padding given by gcc explicit 



The current definition of struct can_frame has a 16-byte size, with 8-byte
alignment, but the 3 bytes of padding are not explicit like the similar 2 bytes
of padding of struct canfd_frame. Make it explicit so it is easier to read.

Signed-off-by: default avatarShawn Landden <shawn@churchofgit.com>
Acked-by: default avatarOliver Hartkopp <socketcan@hartkopp.net>
Signed-off-by: default avatarMarc Kleine-Budde <mkl@pengutronix.de>
parent 239fb791

Documentation/networking/can.txt

+3 −0
Original line number Diff line number Diff line
@@ -268,6 +268,9 @@ solution for a couple of reasons: 
    struct can_frame {

            canid_t can_id;  /* 32 bit CAN_ID + EFF/RTR/ERR flags */

            __u8    can_dlc; /* frame payload length in byte (0 .. 8) */

            __u8    __pad;   /* padding */

            __u8    __res0;  /* reserved / padding */

            __u8    __res1;  /* reserved / padding */

            __u8    data[8] __attribute__((aligned(8)));

    };

include/uapi/linux/can.h

+6 −0
Original line number Diff line number Diff line
@@ -95,11 +95,17 @@ typedef __u32 can_err_mask_t; 
 * @can_dlc: frame payload length in byte (0 .. 8) aka data length code

 *           N.B. the DLC field from ISO 11898-1 Chapter 8.4.2.3 has a 1:1

 *           mapping of the 'data length code' to the real payload length

 * @__pad:   padding

 * @__res0:  reserved / padding

 * @__res1:  reserved / padding

 * @data:    CAN frame payload (up to 8 byte)

 */

struct can_frame {

	canid_t can_id;  /* 32 bit CAN_ID + EFF/RTR/ERR flags */

	__u8    can_dlc; /* frame payload length in byte (0 .. CAN_MAX_DLEN) */

	__u8    __pad;   /* padding */

	__u8    __res0;  /* reserved / padding */

	__u8    __res1;  /* reserved / padding */

	__u8    data[CAN_MAX_DLEN] __attribute__((aligned(8)));

};