This code was using get_user_pages_fast(), in a "Case 2" scenario (DMA/RDMA), using the categorization from [1]. That means that it's time to convert the get_user_pages_fast() + put_page() calls to pin_user_pages_fast() + unpin_user_page() calls. There is some helpful background in [2]: basically, this is a small part of fixing a long-standing disconnect between pinning pages, and file systems' use of those pages. [1] Documentation/core-api/pin_user_pages.rst [2] "Explicit pinning of user-space pages": https://lwn.net/Articles/807108/ Signed-off-by: Souptick Joarder <jrdr.linux@xxxxxxxxx> Cc: John Hubbard <jhubbard@xxxxxxxxxx> Hi, I'm compile tested this, but unable to run-time test, so any testing help is much appriciated. --- drivers/staging/gasket/gasket_page_table.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/drivers/staging/gasket/gasket_page_table.c b/drivers/staging/gasket/gasket_page_table.c index f6d7157..d712ad4 100644 --- a/drivers/staging/gasket/gasket_page_table.c +++ b/drivers/staging/gasket/gasket_page_table.c @@ -449,7 +449,7 @@ static bool gasket_release_page(struct page *page) if (!PageReserved(page)) SetPageDirty(page); - put_page(page); + unpin_user_page(page); return true; } @@ -486,12 +486,12 @@ static int gasket_perform_mapping(struct gasket_page_table *pg_tbl, ptes[i].dma_addr = pg_tbl->coherent_pages[0].paddr + off + i * PAGE_SIZE; } else { - ret = get_user_pages_fast(page_addr - offset, 1, + ret = pin_user_pages_fast(page_addr - offset, 1, FOLL_WRITE, &page); if (ret <= 0) { dev_err(pg_tbl->device, - "get user pages failed for addr=0x%lx, offset=0x%lx [ret=%d]\n", + "pin user pages failed for addr=0x%lx, offset=0x%lx [ret=%d]\n", page_addr, offset, ret); return ret ? ret : -ENOMEM; } -- 1.9.1 _______________________________________________ devel mailing list devel@xxxxxxxxxxxxxxxxxxxxxx http://driverdev.linuxdriverproject.org/mailman/listinfo/driverdev-devel
