Section: VM Functions (9)
mem_map_reserve, mem_map_unreserve - Manipulate flags of virtual memory pages.
These macros cause a page to become reserved/unreserved. A reserved
page is reserved from any further consideration by the linux kernel,
meaning it is not scanned as potentially pageable, or available for
page allocation. The kernel treats reserved pages as memory-mapped
It makes sense for a driver to mark a page reserved, for example, if
the driver supports
with dynamically allocated pages that the target device can access via
MAP_NR(9), get_free_pages(9), mmap(2)
Stephen Williams <firstname.lastname@example.org>
If a page is marked reserved, a call to
will silenty ignore it. If the page was originally allocated by
get_free_page, you must remember to unmark the page before releasing
it to the system. Otherwise, the page is lost.