tree 3ae578a1bd7f971f1f03160d00a1caec6351ead0
parent ddb9fa78b5d97e4107a9404f4146140ef8bf9a5a
author Barret Rhoden <brho@cs.berkeley.edu> 1428337423 -0400
committer Barret Rhoden <brho@cs.berkeley.edu> 1428433619 -0400

Redefines PTE present vs mapped

Mapped now means it points to a physical page in all cases.  Present is
mapped and with bits set for some valid PTE walk.  For instance, a user
read works on x86 with PTE_U and PTE_P.

PTE_P shouldn't be used from the arch-indep code now.

I might have missed something with this commit, like leaking memory or
dirty bits.  Feel free to check out the usages of is_present, is_mapped,
and is_unmapped.