Re: VM subsystem bug in 2.4.0 ?

Linus Torvalds
2001-01-09T18:38:41Z

On 9 Jan 2001, Christoph Rohland wrote:

> Hi Stephen,
>
> On Tue, 9 Jan 2001, Stephen C. Tweedie wrote:
> > D'oh, right --- so can't you lock a segment just by bumping
> > page_count on its pages?
>
> Looks like a good idea.
>
> Oh, and my last posting was partly bogus: I can directly get the pages
> with page cache lookups on the file.

Even more appropriately, you have the inode->i_mapping lists that you can
use directly (no need to do lookups, just walk the list).

Note that bumping the counts is _NOT_ as easy as you seem to think. The
problem: vmtruncate() and friends. It's much easier to just have a flag
that gets cleared on truncate.

Linus