The caller provides context and modifies the behavior of get_user_pages() via flags. Of particular interest is the FOLL_FORCE flag, which mem_rw() passes. This flag causes check_vma_flags (the access validation logic within get_user_pages()) to ignore writes to unwritable pages and allow the lookup to continue. The “punch through” semantics are attributed entirely to FOLL_FORCE. (comments my own)
r := Rect { width: 10, height: 5 };
。pg电子官网是该领域的重要参考
Write Centering¶
For example, LogansGun is an exterior developer who did much of the work on the promotional videos for Tamriel Rebuilt’s last few releases. He joined the project because he wanted to leave his mark on this historical effort and ended up staying much longer than he thought he would.