Re: [PATCH] updated radix-tree pagecache

From: Hugh Dickins (hugh@veritas.com)
Date: Tue Mar 26 2002 - 08:02:12 EST


On Tue, 26 Mar 2002, Andrew Morton wrote:
>
> Aside: This is not related to ratcache: shmem_getpage_locked() is
> setting PG_dirty but not adding the page to mapping->dirty_pages. Is
> this intended?

Yes. It used to be the case that if a tmpfs file page got on to
mapping->dirty_pages, fsync on that file would never escape from
filemap_fdatasync if there was no swap. Hence also "SetPageDirty"
in several places which originally said "set_page_dirty".

Nowadays the "if (!PageLaunder(page)) return fail_writepage(page);"
at the start of shmem_writepage would prevent that hang, and
prevents a subtler tmpfs file corruption we realized later on.

But the dirty_pages list is still a waste of time for tmpfs:
its data does not need to be committed to stable storage.

Hugh

-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/



This archive was generated by hypermail 2b29 : Sun Mar 31 2002 - 22:00:11 EST