From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Tomi Valkeinen , Laurent Pinchart , Sasha Levin Subject: [PATCH 4.9 184/310] drm/omap: fix tiled buffer stride calculations Date: Wed, 11 Apr 2018 20:35:23 +0200 Message-Id: <20180411183630.526777341@linuxfoundation.org> In-Reply-To: <20180411183622.305902791@linuxfoundation.org> References: <20180411183622.305902791@linuxfoundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: 4.9-stable review patch. If anyone has any objections, please let me know. ------------------ From: Tomi Valkeinen [ Upstream commit cc8dd7661ccc2d8dc88921da8e6cc7c2fcdb0341 ] omap_gem uses page alignment for buffer stride. The related calculations are a bit off, though, as byte stride of 4096 gets aligned to 8192, instead of 4096. This patch changes the code to use DIV_ROUND_UP(), which fixes those calculations and makes them more readable. Signed-off-by: Tomi Valkeinen Reviewed-by: Laurent Pinchart Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman --- drivers/gpu/drm/omapdrm/omap_gem.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) --- a/drivers/gpu/drm/omapdrm/omap_gem.c +++ b/drivers/gpu/drm/omapdrm/omap_gem.c @@ -195,7 +195,7 @@ static void evict_entry(struct drm_gem_o size_t size = PAGE_SIZE * n; loff_t off = mmap_offset(obj) + (entry->obj_pgoff << PAGE_SHIFT); - const int m = 1 + ((omap_obj->width << fmt) / PAGE_SIZE); + const int m = DIV_ROUND_UP(omap_obj->width << fmt, PAGE_SIZE); if (m > 1) { int i; @@ -442,7 +442,7 @@ static int fault_2d(struct drm_gem_objec * into account in some of the math, so figure out virtual stride * in pages */ - const int m = 1 + ((omap_obj->width << fmt) / PAGE_SIZE); + const int m = DIV_ROUND_UP(omap_obj->width << fmt, PAGE_SIZE); /* We don't use vmf->pgoff since that has the fake offset: */ pgoff = ((unsigned long)vmf->virtual_address -