From mboxrd@z Thu Jan 1 00:00:00 1970 Message-ID: <4518C7AD.3090507@anu.edu.au> Date: Tue, 26 Sep 2006 16:24:45 +1000 From: Nick Piggin MIME-Version: 1.0 Subject: Re: [PATCH] Make invalidate_inode_pages2() work again References: <20060925231557.32226.66866.stgit@ingres.dsl.sfldmi.ameritech.net> <45186D4A.70009@yahoo.com.au> <1159233613.5442.61.camel@lade.trondhjem.org> <451884C1.8080209@yahoo.com.au> In-Reply-To: <451884C1.8080209@yahoo.com.au> Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org Return-Path: To: Trond Myklebust Cc: Chuck Lever , apkm@osdl.org, linux-mm@kvack.org, steved@redhat.com List-ID: Nick Piggin wrote: > So I really dislike get_user_pages for reasons such as this. IMO it would > be cool if get_user_pages when the caller wants to write, would return > with > the page dirty and a bit set to prevent writeout from cleaning it > until it > has been finished with (via put_user_pages). > > Actually, _ideally_, maybe keeping the mapping around (ie. holding at > least a read lock on mmap_sem) would do the trick. The presence of the > mapping will be seen by the invalidate routines[*], and in general things > might be simplified. No, I guess that isn't going to work, because it'll mean one thread can DoS the others WRT mmap and brk. I'll look into the per-page flag bit idea. -- -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org