Re: ntfs ubc_uiomove error

[Patrick Welche <prlw1%cam.ac.uk@localhost>]

On Thu, Aug 27, 2009 at 01:20:11PM -0400, Christos Zoulas wrote:
> On Aug 27,  4:21pm, dholland-current%netbsd.org@localhost (David Holland) 
> wrote:
> -- Subject: Re: ntfs ubc_uiomove error
> 
> | On Wed, Aug 26, 2009 at 10:22:24AM -0400, Christos Zoulas wrote:
> |  > | I was _reading_ from ntfs vnd, and writing to /tmp (tmpfs or ffs, not 
> sure
> |  > | which now...) The surprise above was that cat worked where cp 
> failed(?!)
> |  > 
> |  > Ah, ok... Now I understand :-) NTFS does not implement mmap, and cp uses
> |  > mmap.
> | 
> | Shouldn't cp be adjusted so it'll fall back to read()?
> 
> Last I checked it failed differently, mmap(2) returned an invalid
> pointer and the the application SEGV'd. Clearly this behavior has
> now changed :-) I don't think that the error is being passed up
> properly, still.

A quick look says that cp falls back to read(), and ntfs uses genfs' mmap
which just returns zero, which means success, no? Rather than return
not implemented...

Cheers,

Patrick