panic after removing usb flash drive

Daniel O'Connor doconnor at gsoft.com.au
Wed Aug 31 13:25:51 GMT 2005


On Wednesday 31 August 2005 22:43, Eric Anderson wrote:
> This is where I think it would be great to have a sort of 'flashfs' -
> something like a UFS2 filesystem, but read only until a write happens,
> and all writes would be synchronous, and after the write occurs, the fs
> goes back to a 'read only' state.  Maybe this could be done with
> gjournal or even unionfs - mount the usb flash read only, do all writes
> to a memory backed disk, and then flush the writes out to the usb flash
> periodically.  Not perfect, but maybe this will stir some ideas up.

I think if you can differentiate behaviour for normal file systems based on 
some information about the device then it would be good.

ie if it is a removable type device the default behaviour would be to disable 
write caching and mount it synchronously. Coupled with a kernel that is 
willing to throw away pages dirtied on such a volume you would be able to 
readily hot plug a device without too much worry about data loss.

-- 
Daniel O'Connor software and network engineer
for Genesis Software - http://www.gsoft.com.au
"The nice thing about standards is that there
are so many of them to choose from."
  -- Andrew Tanenbaum
GPG Fingerprint - 5596 B766 97C0 0E94 4347 295E E593 DC20 7B3F CE8C
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