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School of Computer Science & Engineering
University of New South Wales
 Advanced Operating Systems 
 COMP9242 2002/S2 

Fpage Mapping

• In general send and receive fpages will be of different size:
  • page fault receive fpage covers full address space,
  • there may be several send fpage, but only one receive fpage,
  • fpage may need to be mapped at different addresses in sender and receiver (e.g., on page fault).
• Need ability to specify where an fpage gets mapped
• Each send fpage is accompanied with a hotspot address (send base)
  • Determines mapping address if receive fpage is big enough.

Send fpage information

w1

:

write-permission bit, unset ==> fpage will be mapped read-only

:

grant bit, set ==> fpage will be granted

.