XFS: fix zoned gc threshold math for 32-bit arches
xfs_zoned_need_gc makes use of mult_frac() to calculate the threshold
for triggering the zoned garbage collector, but, turns out mult_frac()
doesn't properly work with 64-bit data types and this caused build
failures on some 32-bit architectures.
Fix this by essentially open coding mult_frac() in a 64-bit friendly
way.
Notice we don't need to bother with counters underflow here because
xfs_estimate_freecounter() will always return a positive value, as it
leverages percpu_counter_read_positive to read such counters.
Fixes: 845abeb1f06a ("xfs: add tunable threshold parameter for triggering zone GC")
1 file changed
