[PATCH net-next 01/12] bitfield.h: add FIELD_FIT() helper
From: Jakub Kicinski <hidden>
Date: 2017-02-09 17:26:21
Subsystem:
bitmap api, netronome ethernet drivers, networking drivers, the rest · Maintainers:
Yury Norov, Andrew Lunn, "David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Linus Torvalds
Add a helper for checking at runtime that a value will fit inside a specified field/mask. Signed-off-by: Jakub Kicinski <redacted> --- drivers/net/ethernet/netronome/nfp/nfp_bpf.h | 2 -- include/linux/bitfield.h | 13 +++++++++++++ 2 files changed, 13 insertions(+), 2 deletions(-)
diff --git a/drivers/net/ethernet/netronome/nfp/nfp_bpf.h b/drivers/net/ethernet/netronome/nfp/nfp_bpf.h
index 76a19f1796af..9513c80f7be5 100644
--- a/drivers/net/ethernet/netronome/nfp/nfp_bpf.h
+++ b/drivers/net/ethernet/netronome/nfp/nfp_bpf.h@@ -39,8 +39,6 @@ #include <linux/list.h> #include <linux/types.h> -#define FIELD_FIT(mask, val) (!((((u64)val) << __bf_shf(mask)) & ~(mask))) - /* For branch fixup logic use up-most byte of branch instruction as scratch * area. Remember to clear this before sending instructions to HW! */
diff --git a/include/linux/bitfield.h b/include/linux/bitfield.h
index f6505d83069d..8b9d6fff002d 100644
--- a/include/linux/bitfield.h
+++ b/include/linux/bitfield.h@@ -63,6 +63,19 @@ }) /** + * FIELD_FIT() - check if value fits in the field + * @_mask: shifted mask defining the field's length and position + * @_val: value to test against the field + * + * Return: true if @_val can fit inside @_mask, false if @_val is too big. + */ +#define FIELD_FIT(_mask, _val) \ + ({ \ + __BF_FIELD_CHECK(_mask, 0ULL, _val, "FIELD_FIT: "); \ + !((((typeof(_mask))_val) << __bf_shf(_mask)) & ~(_mask)); \ + }) + +/** * FIELD_PREP() - prepare a bitfield element * @_mask: shifted mask defining the field's length and position * @_val: value to put in the field
--
2.11.0