On Wed, Jun 17, 2020 at 7:50 AM Souptick Joarder <jrdr.li...@gmail.com> wrote:
>
> First, convert set_page_dirty() to set_page_dirty_lock()
>
> Second, there is an interval in there after set_page_dirty() and
> before put_page(), in which the device could be running and setting
> pages dirty. Moving set_page_dirty_lock() after dma_unmap_sg().
>
> Signed-off-by: Souptick Joarder <jrdr.li...@gmail.com>
> Suggested-by: John Hubbard <jhubb...@nvidia.com>
> Cc: Dan Carpenter <dan.carpen...@oracle.com>
> Cc: Bharath Vedartham <linux.b...@gmail.com>
> ---
> drivers/staging/kpc2000/kpc_dma/fileops.c | 6 +++---
> 1 file changed, 3 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/staging/kpc2000/kpc_dma/fileops.c
> b/drivers/staging/kpc2000/kpc_dma/fileops.c
> index b136353..bcce86c 100644
> --- a/drivers/staging/kpc2000/kpc_dma/fileops.c
> +++ b/drivers/staging/kpc2000/kpc_dma/fileops.c
> @@ -214,13 +214,13 @@ void transfer_complete_cb(struct aio_cb_data *acd,
> size_t xfr_count, u32 flags)
> BUG_ON(!acd->ldev);
> BUG_ON(!acd->ldev->pldev);
>
> + dma_unmap_sg(&acd->ldev->pldev->dev, acd->sgt.sgl, acd->sgt.nents,
> acd->ldev->dir);
> +
> for (i = 0 ; i < acd->page_count ; i++) {
> if (!PageReserved(acd->user_pages[i]))
Question -> is PageReserved() used with specific purpose not PageDirty() ??
> - set_page_dirty(acd->user_pages[i]);
> + set_page_dirty_lock(acd->user_pages[i]);
> }
>
> - dma_unmap_sg(&acd->ldev->pldev->dev, acd->sgt.sgl, acd->sgt.nents,
> acd->ldev->dir);
> -
> for (i = 0 ; i < acd->page_count ; i++)
> put_page(acd->user_pages[i]);
>
> --
> 1.9.1
>
