Re: [PATCH 1/1] net/rds: Track user mapped pages through special API
From: David Miller
Date: Sun Feb 16 2020 - 21:37:34 EST
From: John Hubbard <jhubbard@xxxxxxxxxx>
Date: Tue, 11 Feb 2020 19:03:55 -0800
> From: Leon Romanovsky <leonro@xxxxxxxxxxxx>
> Convert net/rds to use the newly introduces pin_user_pages() API,
> which properly sets FOLL_PIN. Setting FOLL_PIN is now required for
> code that requires tracking of pinned pages.
> Note that this effectively changes the code's behavior: it now
> ultimately calls set_page_dirty_lock(), instead of set_page_dirty().
> This is probably more accurate.
> As Christoph Hellwig put it, "set_page_dirty() is only safe if we are
> dealing with a file backed page where we have reference on the inode it
> hangs off." 
>  https://lore.kernel.org/r/20190723153640.GB720@xxxxxx
> Cc: Hans Westgaard Ry <hans.westgaard.ry@xxxxxxxxxx>
> Cc: Santosh Shilimkar <santosh.shilimkar@xxxxxxxxxx>
> Signed-off-by: Leon Romanovsky <leonro@xxxxxxxxxxxx>
> Signed-off-by: John Hubbard <jhubbard@xxxxxxxxxx>
Applied, thank you.