[RFC,PATCH 0/4] Dynamic Pseudo Root

[Tom Haynes]

Steve Dickson wrote:
> Brent Callaghan wrote:
>   
>> On Dec 8, 2007, at 6:36 AM, Steve Dickson wrote:
>>     
>>>
>>> So can I assume that Solaris does pump all the exports to a table
>>> in the kernel?
>>>       
>> Yes, BSD and MacOSX do it that way too.  Though I can also see some
>> advantages in having exports discovered on the fly.
>>     
> I kinda like the approach of building the in-kernel export cache 
> as the exports are accessed. Why pump ton of data into the kernel
> that may or may not be used?
>   


What happens when the server reboots, comes back up, and clients start 
presenting valid FHs
to the server?

How do you detect the need to load the export vs ESTALE?

Does the FH have the mount point stored in it somehow?

Or does Linux assume that if a client has a valid FH, then it has access 
to that file? And if
that file is a directory, then it

And that exposes a performance issue - if it were just mountd requests 
which had to deal
with checking to see if exports are loaded, that isn't too bad. But if 
every NFS v2/v3/v4
request also has to perform the check, then this might not be welcome.

Finally, how do you store the state? I've done this type of thing in the 
past and added a
2 bit status flag to the in kernel export structure. But that entails 
you paying the cost of
all of the rest of structure. (In my case, the number of unloaded 
exports was very small
compared to loaded ones.) And that doesn't sound like your vision above.