From mboxrd@z Thu Jan 1 00:00:00 1970 From: Nikhilesh Reddy Subject: Re: [PATCH] fuse: Add support for fuse stacked I/O Date: Wed, 20 Jan 2016 15:24:12 -0800 Message-ID: <56A0171C.6050108@codeaurora.org> References: <565394BE.4040506@codeaurora.org> <5696E366.2080605@codeaurora.org> <20160114045716.GB8006@kroah.com> <5697EF97.9020800@codeaurora.org> <871t9i91e1.fsf@thinkpad.rath.org> <56994884.9060002@codeaurora.org> <569DA62B.7070701@codeaurora.org> Mime-Version: 1.0 Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <569DA62B.7070701-sgV2jX0FEOL9JmXXK+q4OQ@public.gmane.org> Sender: linux-api-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Linus Torvalds Cc: Andy Lutomirski , Nikolaus Rath , fuse-devel , Al Viro , Greg KH , linux-fsdevel , Linux API , Jan Kara , Theodore Ts'o , sven.utcke-Mmb7MZpHnFY@public.gmane.org, Miklos Szeredi , Richard Weinberger , Linux Kernel Mailing List , Antonio SJ Musumeci List-Id: linux-api@vger.kernel.org On 01/18/2016 06:57 PM, Nikhilesh Reddy wrote: > On 01/15/2016 01:53 PM, Linus Torvalds wrote: >> On Fri, Jan 15, 2016 at 1:46 PM, Andy Lutomirski >> wrote: >> >>> If mmap sets vm_file to the underlying thing, wouldn't CRIU and >>> anything else that uses map_files get confused? Or did you have >>> something else in mind? >> >> Why would they care? >> >> Also, I don't think you actually need to change vm_file - we have this >> whole notion of "inode->i_data" vs "inode->i_mapping". >> >> So I think you could set the "i_mapping" of the fuse inode to be the >> i_mapping of the passed-through-to inode, and it should just work. >> >> And no, I didn't look into this very deeply, and maybe there is some >> annoying detail that would make that not work well. But that's part of >> the whole point of the i_mapping indirection: so that you can share >> the page cache when you have two separate anchor points. I think coda >> uses it for the local caching, and block devices use it to not have >> mapping aliases between different inodex that all are the same block >> device. >> >> Linus >> > > Hi > > Thanks for your support. > > I am looking into adding the mmap by change the i_mmaping but seems to > be getting stuck for some stress tests. > > Once i get that debugged and working i will definitely send out a new > patch with that functionality. > > ( Sending it as a second patch will help make it easier to go through > the legal redtape and procedures i am forced to follow). > > For now i am going to update the current patch and call it "passthrough" > as you suggested and also update the commit message giving a clearer > explanation of the motivation. > > Once i get it tested I can send it out for consideration and review > > Please do let me know if you have any questions or concerns on this and > i will try my best to address them all. > > I have just sent out the latest version of the patch in the email with the subject [PATCH v3] fuse: Add support for passthrough read/write Please do let me know if you have any questions or concerns on this and i will try my best to address them all. -- Thanks Nikhilesh Reddy Qualcomm Innovation Center, Inc. The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum, a Linux Foundation Collaborative Project.