net: qualcomm: rmnet: use masks instead of C bit-fields

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The actual layout of bits defined in C bit-fields (e.g. int foo : 3)
is implementation-defined.  Structures defined in <linux/if_rmnet.h>
address this by specifying all bit-fields twice, to cover two
possible layouts.

I think this pattern is repetitive and noisy, and I find the whole
notion of compiler "bitfield endianness" to be non-intuitive.

Stop using C bit-fields for the command/data flag and the pad length
fields in the rmnet_map structure, and define a single-byte flags
field instead.  Define a mask for the single-bit "command" flag,
and another mask for the encoded pad length.  The content of both
fields can be accessed using a simple bitwise AND operation.

Signed-off-by: Alex Elder <elder@linaro.org>
Reviewed-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Reviewed-by: Alexander Duyck <alexanderduyck@fb.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

...

This commit is contained in:

Alex Elder 2021-03-15 16:51:49 -05:00 • committed by David S. Miller

parent 9d131d044f

commit 16653c16d2

3 changed files with 15 additions and 16 deletions

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4

drivers/net/ethernet/qualcomm/rmnet/rmnet_handlers.c

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4

drivers/net/ethernet/qualcomm/rmnet/rmnet_map_data.c

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23

include/linux/if_rmnet.h

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