a89ec8bc3b
. 'anonymous' cache blocks (retrieved with NO_DEV as dev parameter) were used to implement read()s from holes in inodes that should return zeroes . this is an awkward special case in the cache code though and there's a more direct way to implement the same functionality: instead of copying from a new, anonymous, zero block, to the user target buffer, simply sys_safememset the user target buffer directly. as this was the only use of this feature, this is all that's needed to simplify the cache code a little.