modified to accomplish a direct page -> bus translation, without requiring
a virtual address mapping (unlike the earlier scheme of virtual address
-> bus translation). So this works uniformly for high-memory pages (which
-do not have a correponding kernel virtual address space mapping) and
+do not have a corresponding kernel virtual address space mapping) and
low-memory pages.
Note: Please refer to DMA-mapping.txt for a discussion on PCI high mem DMA
i. Binary tree
AS and deadline i/o schedulers use red black binary trees for disk position
sorting and searching, and a fifo linked list for time-based searching. This
-gives good scalability and good availablility of information. Requests are
+gives good scalability and good availability of information. Requests are
almost always dispatched in disk sort order, so a cache is kept of the next
request in sort order to prevent binary tree lookups.