Messages in this thread | | | Date | Thu, 12 Jul 2012 07:43:49 +0900 | Subject | Re: [PATCH] nfs-util: Add cache_flush in mountd UMNT procedure. | From | Namjae Jeon <> |
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2012/7/12, Namjae Jeon <linkinjeon@gmail.com>: > 2012/7/11, J. Bruce Fields <bfields@fieldses.org>: >> On Wed, Jul 11, 2012 at 01:10:53PM +0900, Namjae Jeon wrote: >>> 2012/7/10, J. Bruce Fields <bfields@fieldses.org>: >>> > On Sat, Jul 07, 2012 at 11:17:39PM -0400, Namjae Jeon wrote: >>> >> For removing storage device - user needs to safely un-mount the >>> >> device >>> >> and then eject. But if 'EBUSY' occurs in umount then it will create >>> >> confusion for the user as it will mean some I/O is in progress - and >>> >> won't allow user to safely ejecting device. >>> > >>> Hi James. >>> > The one drawback is that recovering from the cache flushes might be a >>> > little expensive if you have a lot of exports in use. >>> Good point. I will look for more there is the method flush only mount >>> entry. >> >> I don't think there's a good way to flush only one entry. >> >> Also, this isn't going to help for NFSv4 since a v4 client won't do an >> unmount call. > Okay. >> >>> > I'm curious, since you said this was for a usb disk: are users >>> > expected >>> > to just unplug it (in which case--is it read only?) or do they have >>> > some >>> > way of unmounting before they pull the plug? >>> Users expected to unplug it on both read only and read/write. >>> And there is no way that system be prepared to know about the >>> intelligence when the user is going to unplug. >>> if the user really want to detach the device safely. There is an >>> option like the desktop PC - where, we can say - umount/eject the >>> device. There is a proper user interface for safe removal. >>> but they can not unplug safely if usb device is mounted with nfs >>> because of this issue. >> >> Ideal might be to get some way to notify nfsd when the device >> diseappears or the filesystem wants to unmount. I don't know how to do >> that. > Okay. I will look for good solution for this issue. > Thanks. Hi James. I have a question. If we found the method to notify nfs when unplugging device, Can nfsd flush only entry of usb mount ?
Thanks.
>> >> --b. >> >
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