Hello, I just read about the kiobuf interface in the Linux Device Driver book from Rubini/Corbet, and there is one point, which I don't understand: - map_user_kiobuf() forces the pages within a user space address range into physical memory, and increments their usage count, which subsequently prevents the pages from being swapped out. - lock_kiovec() sets the PG_locked flag for the pages in the kiobufs of a kiovec. The PG_locked flag prevents the pages from being swapped out, which is however already ensured by map_user_kiobuf(). (1) What is the reason to call lock_kiovec()? (2) Are there any additional effects (other than prevent the page from being swapped out) resulting from a set PG_locked flag? (3) Does anyone know a more detailed documentation of the kiobuf interface, than the book mentioned above? P.S. please put me on CC in your reply, since I am not in the mailing list. Thanks for any help, best regards Martin Maletinsky -- Supercomputing System AG email: maletinsky@scs.ch Martin Maletinsky phone: +41 (0)1 445 16 05 Technoparkstrasse 1 fax: +41 (0)1 445 16 10 CH-8005 Zurich -- Kernelnewbies: Help each other learn about the Linux kernel. Archive: http://mail.nl.linux.org/kernelnewbies/ FAQ: http://kernelnewbies.org/faq/
