On 11/4/19 9:44 AM, Jerome Glisse wrote:
On Sun, Nov 03, 2019 at 01:18:04PM -0800, John Hubbard wrote:
Convert drm/via to use the new pin_user_pages_fast() call, which sets FOLL_PIN. Setting FOLL_PIN is now required for code that requires tracking of pinned pages, and therefore for any code that calls put_user_page().
Reviewed-by: Ira Weiny ira.weiny@intel.com Signed-off-by: John Hubbard jhubbard@nvidia.com
Please be more explicit that via_dmablit.c is already using put_user_page() as i am expecting that any conversion to pin_user_pages*() must be pair with a put_user_page(). I find above commit message bit unclear from that POV.
OK. This one, and the fs/io_uring (patch 9) and net/xdp (patch 10) were all cases that had put_user_page() pre-existing. I will add something like the following to each commit description, for v3:
In partial anticipation of this work, the drm/via driver was already calling put_user_page() instead of put_page(). Therefore, in order to convert from the get_user_pages()/put_page() model, to the pin_user_pages()/put_user_page() model, the only change required is to change get_user_pages() to pin_user_pages().
thanks,
John Hubbard NVIDIA
Reviewed-by: Jérôme Glisse jglisse@redhat.com
drivers/gpu/drm/via/via_dmablit.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/via/via_dmablit.c b/drivers/gpu/drm/via/via_dmablit.c index 3db000aacd26..37c5e572993a 100644 --- a/drivers/gpu/drm/via/via_dmablit.c +++ b/drivers/gpu/drm/via/via_dmablit.c @@ -239,7 +239,7 @@ via_lock_all_dma_pages(drm_via_sg_info_t *vsg, drm_via_dmablit_t *xfer) vsg->pages = vzalloc(array_size(sizeof(struct page *), vsg->num_pages)); if (NULL == vsg->pages) return -ENOMEM;
- ret = get_user_pages_fast((unsigned long)xfer->mem_addr,
- ret = pin_user_pages_fast((unsigned long)xfer->mem_addr, vsg->num_pages, vsg->direction == DMA_FROM_DEVICE ? FOLL_WRITE : 0, vsg->pages);
-- 2.23.0