procfs feature or bug?

Sandip Bhattacharya (sandip@webyarn.com)
Wed, 19 Sep 2001 15:53:32 +0530


[Do cc me replies. Thanks.]

Hi!

I was trying out the multipage procfs entries, when i found out that i
was having a problem.

I am trying to use the "hack" by Paul Russell to allow mangling of
filepos using ``*start'' entries as my personal page offset. Now, for
multipage entries, whatever i set as *start should be coming back to
me as offset when the next page is called.

But in fs/proc/generic.c in proc_file_read() at the end we have (
after the first page has been "copied_to_user")

*ppos += start < page ? (long) start : n;

But this _adds_ the contents of start to the offset, in the case where
I am supplying the offset in ``start''. Shouldn't this just be
_replacing_ ? 'Cause in this case the offsets get cumulatively added,
causing an oops at the end for me :(

Or am I missing something big???

- Sandip

--
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Sandip Bhattacharya
Office: sandip@mindsw.com       Home: sandipb@bigfoot.com
Mindframe Software
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