Re: [PATCH] nfs-util: Add cache_flush in mountd UMNT procedure.

[Namjae Jeon <linkinjeon@gmail.com>]

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'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.
>
> --b.
>