Using roundup_pow_of_two() on (ondisk_extradevs + 1) triggers
a potential 64-bit shift warning because of the internal n-1 logic
in the macro.

Since ondisk_extradevs is already validated to be non-zero, use
fls_long() directly to calculate the device_id_mask. This resolves
the 'shiftTooManyBits' warning and is mathematically equivalent.

Signed-off-by: Nithurshen <[email protected]>
---
 lib/super.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/lib/super.c b/lib/super.c
index 088c9a0..bff9b1e 100644
--- a/lib/super.c
+++ b/lib/super.c
@@ -29,7 +29,8 @@ static bool check_layout_compatibility(struct erofs_sb_info 
*sbi,
 static int erofs_init_devices(struct erofs_sb_info *sbi,
                              struct erofs_super_block *dsb)
 {
-       unsigned int ondisk_extradevs, i;
+       unsigned int i;
+       u16 ondisk_extradevs;
        erofs_off_t pos;
 
        sbi->total_blocks = sbi->primarydevice_blocks;
@@ -49,7 +50,7 @@ static int erofs_init_devices(struct erofs_sb_info *sbi,
                return 0;
 
        sbi->extra_devices = ondisk_extradevs;
-       sbi->device_id_mask = roundup_pow_of_two(ondisk_extradevs + 1) - 1;
+       sbi->device_id_mask = (1UL << fls_long(ondisk_extradevs)) - 1;
        sbi->devs = calloc(ondisk_extradevs, sizeof(*sbi->devs));
        if (!sbi->devs)
                return -ENOMEM;
-- 
2.51.0


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