Re: [PATCH 3/9] bitmap: Use FIELD_PREP() in expansion of FIELD_PREP_WM16()
From: Andy Shevchenko <hidden>
Date: 2025-12-09 15:46:28
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On Tue, Dec 09, 2025 at 10:03:07AM +0000, david.laight.linux@gmail.com wrote:
Instead of directly expanding __BF_FIELD_CHECK() (which really ought not be used outside bitfield) and open-coding the generation of the masked value, just call FIELD_PREP() and add an extra check for the mask being at most 16 bits.
...
+#define FIELD_PREP_WM16(mask, val) \
+({ \
+ __auto_type _mask = mask; \
+ u32 _val = FIELD_PREP(_mask, val); \+ BUILD_BUG_ON_MSG(_mask > 0xffffu, \ + "FIELD_PREP_WM16: mask too large"); \
Can it be static_assert() instead?
+ _val | (_mask << 16); \ +})
-- With Best Regards, Andy Shevchenko