Andrew Morton writes:

 > Andrew Morton wrote:

 > >

 > > David Chow [off-list ref] wrote:

 > > >

 > > > Hi,

 > > >

 > > > If I do the following to an inode mapping page .

 > > >

 > > > 1. Generate a "struct page" from read_cache_page()

 > > > 2. kmap() the page, do some memset() (Dirty the page)

 > > > 3. kunmap() and page_cache_release() the page.

 > > >

 > >

 > > The VFS does not know that the page has changed.

 > >

 > > You should do:

 > >

 > >         lock_page(page);

 > >         memset()

 > >         set_page_dirty(page);

 > >         unlock_page(page);

 > >

 > > the page will be written to disk on the next kupdate cycle.

 >

 > Make that:

 >

 > 	lock_page(page);

 > 	kaddr = kmap_atomic(page, KM_USER0);

 > 	memset(kaddr, ...);

 > 	flush_dcache_page(page)

 > 	kunmap_atomic(kaddr, KM_USER0);

 > 	set_page_dirty(page);

Shouldn't mark_page_accessed() go here?

 > 	unlock_page(page);

Nikita.

Thanks for your help. However, do I have to deal with page ref cnts?

regards,
David


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