On Mon 20 May 06:53 PDT 2019, Alex Elder wrote:
> Using C bitfields (e.g. int foo : 3) is not portable. So stop
> using them for the command/data flag and the pad length fields in
> the rmnet_map structure. Instead, use the functions defined in
> <linux/bitfield.h> along with field mask constants to extract or
> assign values within an integral structure member of a known size.
>
Reviewed-by: Bjorn Andersson <bjorn.andersson@xxxxxxxxxx>
> Signed-off-by: Alex Elder <elder@xxxxxxxxxx>
> ---
> drivers/net/ethernet/qualcomm/rmnet/rmnet_handlers.c | 5 +++--
> drivers/net/ethernet/qualcomm/rmnet/rmnet_map.h | 8 +++++---
> drivers/net/ethernet/qualcomm/rmnet/rmnet_map_data.c | 5 ++++-
> 3 files changed, 12 insertions(+), 6 deletions(-)
>
> diff --git a/drivers/net/ethernet/qualcomm/rmnet/rmnet_handlers.c b/drivers/net/ethernet/qualcomm/rmnet/rmnet_handlers.c
> index 4c1b62b72504..5fff6c78ecd5 100644
> --- a/drivers/net/ethernet/qualcomm/rmnet/rmnet_handlers.c
> +++ b/drivers/net/ethernet/qualcomm/rmnet/rmnet_handlers.c
> @@ -13,6 +13,7 @@
> *
> */
>
> +#include <linux/bitfield.h>
> #include <linux/netdevice.h>
> #include <linux/netdev_features.h>
> #include <linux/if_arp.h>
> @@ -70,7 +71,7 @@ __rmnet_map_ingress_handler(struct sk_buff *skb,
> u16 len, pad;
> u8 mux_id;
>
> - if (map_header->cd_bit) {
> + if (u8_get_bits(map_header->cmd_pad_len, RMNET_MAP_CMD_FMASK)) {
> if (port->data_format & RMNET_FLAGS_INGRESS_MAP_COMMANDS)
> return rmnet_map_command(skb, port);
>
> @@ -78,7 +79,7 @@ __rmnet_map_ingress_handler(struct sk_buff *skb,
> }
>
> mux_id = map_header->mux_id;
> - pad = map_header->pad_len;
> + pad = u8_get_bits(map_header->cmd_pad_len, RMNET_MAP_PAD_LEN_FMASK);
> len = ntohs(map_header->pkt_len) - pad;
>
> if (mux_id >= RMNET_MAX_LOGICAL_EP)
> diff --git a/drivers/net/ethernet/qualcomm/rmnet/rmnet_map.h b/drivers/net/ethernet/qualcomm/rmnet/rmnet_map.h
> index a30a7b405a11..a56209645c81 100644
> --- a/drivers/net/ethernet/qualcomm/rmnet/rmnet_map.h
> +++ b/drivers/net/ethernet/qualcomm/rmnet/rmnet_map.h
> @@ -40,13 +40,15 @@ enum rmnet_map_commands {
> };
>
> struct rmnet_map_header {
> - u8 cd_bit:1;
> - u8 reserved_bit:1;
> - u8 pad_len:6;
> + u8 cmd_pad_len; /* RMNET_MAP_* */
> u8 mux_id;
> __be16 pkt_len;
> } __aligned(1);
>
> +#define RMNET_MAP_CMD_FMASK GENMASK(0, 0) /* 0: data; 1: cmd */
> +#define RMNET_MAP_RESERVED_FMASK GENMASK(1, 1)
> +#define RMNET_MAP_PAD_LEN_FMASK GENMASK(7, 2)
> +
> struct rmnet_map_dl_csum_trailer {
> u8 reserved1;
> u8 valid:1;
> diff --git a/drivers/net/ethernet/qualcomm/rmnet/rmnet_map_data.c b/drivers/net/ethernet/qualcomm/rmnet/rmnet_map_data.c
> index 498f20ba1826..10d2d582a9ce 100644
> --- a/drivers/net/ethernet/qualcomm/rmnet/rmnet_map_data.c
> +++ b/drivers/net/ethernet/qualcomm/rmnet/rmnet_map_data.c
> @@ -13,6 +13,7 @@
> *
> */
>
> +#include <linux/bitfield.h>
> #include <linux/netdevice.h>
> #include <linux/ip.h>
> #include <linux/ipv6.h>
> @@ -301,7 +302,9 @@ struct rmnet_map_header *rmnet_map_add_map_header(struct sk_buff *skb,
>
> done:
> map_header->pkt_len = htons(map_datalen + padding);
> - map_header->pad_len = padding & 0x3F;
> + /* This is a data packet, so cmd field is 0 */
> + map_header->cmd_pad_len =
> + u8_encode_bits(padding, RMNET_MAP_PAD_LEN_FMASK);
>
> return map_header;
> }
> --
> 2.20.1
>
