A virtual memory system including a local-to-global virtual address
translator for translating local virtual addresses having associated task
specific address spaces into global virtual addresses corresponding to an
address space associated with multiple tasks, and a global
virtual-to-physical address translator for translating global virtual
addresses to physical addresses. Protection information is provided by
each of the local virtual-to-global virtual address translator, the global
virtual-to-physical address translator, the cache tag storage, or a
protection information buffer depending on whether a cache hit or miss
occurs during a given data or instruction access. The cache is
configurable such that it can be configured into a buffer portion or a
cache portion for faster cache accesses.