hummm, wow very new informations to me...

today linux don't have a generic badblock remap?! that's what i understood?
for example... ext2,3,4,xfs,reiserfs,zfs, and others fs, they handle
badblock by their self? right?

it's a nice information i never thinked about a layer only for
badblock reallocation, i read/write in this list of linux-raid when
the started the badblock development, in some time near to raid1 write
multithread

today the badblock of raid1 is embedded in the source? or it's easy to
implement a new layer just to badblock realloc logic?

about "mkswap -c" it just show information like you told, i'm a bit
surprised about no badblock at swap that's information is new to me i
will read about others os (freebsd, reactos, etc) to check how they
handle this there

I'm rethinking now about the swap as a file in a filesystem, this
could increase security or another solution is better?