5.2.4 Get Physical Address
- INT CnvPhysicalAddr( VP vaddr, INT len, VP *paddr )
vaddr Local address
len Memory space size (in bytes)
paddr Returns physical address
return code Returns size (in bytes) of physical address contiguous space, or error
Gets the physical address corresponding to logical address vaddr, returning the result in paddr.
This function also passes in the return code the size of contiguous space included in len bytes from vaddr. Accordingly, only the space of the size passed in the return code starting from paddr is valid.
The space for which the physical address is obtained must be locked (made resident).
On the assumption of DMA transfer, memory caching is turned o. for the space whose physical address is obtained (the memory space starting from paddr of the size passed in the return code).
When the space is made nonresident (unlocked), caching goes back on.
If it is not possible to make memory cached o. partly by a hardware limitation, this API .ush the cache memory (that is, write back it and make it disable).
E_MACV The memory does not exist
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