Messages in this thread | | | Date | Thu, 18 Mar 2010 13:55:43 -0400 | From | Valerie Aurora <> | Subject | Re: [RFC PATCH] Show data flow for file copyup in unions |
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On Thu, Mar 18, 2010 at 05:10:57PM +0900, J. R. Okajima wrote: > > Valerie Aurora: > > I think what people will expect is that we copy up in that case. I > > can think of ways this can go wrong, but perhaps that should be an > > explicit requirement on the top-layer file system, that it can handle > > create/unlink() in a directory without write permission. > > I am not sure such requirement is the right way. > How about delegating open() to keventd or some other workqueue which > will succeed to create files under a directory without write permission? > Of course, we should handle some error cases after creating a file.
Hm, I don't understand how handing it off to another thread would help. The thing I am worried about is some internal assumption in the file system that a directory without write permission can't be changed. Totally manufactured example:
somefs_create() { BUG_ON(IS_RDONLY(dir->d_inode); [...] }
-VAL
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