diff options
| author | Arvind Sankar <nivedita@alum.mit.edu> | 2020-03-19 22:00:22 -0400 |
|---|---|---|
| committer | Ard Biesheuvel <ardb@kernel.org> | 2020-04-23 20:15:06 +0200 |
| commit | 9867fc9de6a6a7a54edb2c43540c6db226e84a14 (patch) | |
| tree | 5b72b1c7bcc5446d069a8bad42e3bd8b79363b08 | |
| parent | f1d1853bdbcfb2d00ae0b850baf26d87e6d363d8 (diff) | |
efi/gop: Use helper macros for find_bits
Use the __ffs/__fls macros to calculate the position and size of the
mask.
Correct type of mask to u32 instead of unsigned long.
Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu>
Link: https://lore.kernel.org/r/20200320020028.1936003-9-nivedita@alum.mit.edu
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
| -rw-r--r-- | drivers/firmware/efi/libstub/gop.c | 26 |
1 files changed, 8 insertions, 18 deletions
diff --git a/drivers/firmware/efi/libstub/gop.c b/drivers/firmware/efi/libstub/gop.c index 7b0baf9a912f..8bf424f35759 100644 --- a/drivers/firmware/efi/libstub/gop.c +++ b/drivers/firmware/efi/libstub/gop.c @@ -5,6 +5,7 @@ * * ----------------------------------------------------------------------- */ +#include <linux/bitops.h> #include <linux/efi.h> #include <linux/screen_info.h> #include <asm/efi.h> @@ -12,27 +13,16 @@ #include "efistub.h" -static void find_bits(unsigned long mask, u8 *pos, u8 *size) +static void find_bits(u32 mask, u8 *pos, u8 *size) { - u8 first, len; - - first = 0; - len = 0; - - if (mask) { - while (!(mask & 0x1)) { - mask = mask >> 1; - first++; - } - - while (mask & 0x1) { - mask = mask >> 1; - len++; - } + if (!mask) { + *pos = *size = 0; + return; } - *pos = first; - *size = len; + /* UEFI spec guarantees that the set bits are contiguous */ + *pos = __ffs(mask); + *size = __fls(mask) - *pos + 1; } static void |