Re: Advice sought on how to lock multiple pages in ->prepare_write and ->writepage

Matthew Wilcox
2005-02-01T01:29:30Z

On Fri, Jan 28, 2005 at 02:53:41PM -0800, Bryan Henderson wrote:
> >Just putting up my hand to say "yeah, us too" - we could also make
> >use of that functionality, so we can grok existing XFS filesystems
> >that have blocksizes larger than the page size.
>
> IBM Storage Tank has block size > page size and has the same problem. This
> is one of several ways that Storage Tank isn't generic enough to use
> generic_file_write() and generic_file_read(), so it doesn't. That's not a
> terrible way to go, by the way. At some point, making the generic
> interface complex enough to handle every possible filesystem becomes worse
> than every filesystem driver having its own code.

That's certainly true; but it might make sense to write a
multipage_file_read() and multipage_file_write() that can be shared
between the filesystems that do need this complexity.

--
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