From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 4E4F3C04A6A for ; Tue, 15 Aug 2023 13:52:26 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237362AbjHONvz (ORCPT ); Tue, 15 Aug 2023 09:51:55 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:46506 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235071AbjHONve (ORCPT ); Tue, 15 Aug 2023 09:51:34 -0400 Received: from mgamail.intel.com (mgamail.intel.com [192.55.52.120]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id DFA06138 for ; Tue, 15 Aug 2023 06:51:33 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1692107493; x=1723643493; h=date:from:to:cc:subject:message-id:references: mime-version:in-reply-to; bh=gEWWWn6PnBw0uP74Ou/fHMCn6RcO7ifuOGqpIrzxB3I=; b=DAggYLvtfo6mIIIodp/ospEMVhPXeLsiMjUkOV9htqA6ShThY/okoTkM CrGsCufeEnrz7pBADHv6FGRGqOwgbskSAOQzYYvJ0zO6ldLL/zYbVp8NU J8vOCAdwu5z/UOV6K3OCSDOiWAwCV9OzprXA7flu8X31ao6I5eBr6eY8i jVwJVRDjojD7T7+I/A5N+bv+0rn3hO+q9nJ4uju3g3vWO19TqoFDaXekl hTSdc79O2w+qYhpM0tvIWVoLEZZl+9CkhszEHkQ4jgR5ATSG0+/pYT8Qh 7+oMwMm9KQmfnP3ge3an3vCONb//Xj+8iaC4RXcYGSg+3QUd6uJmynK9/ g==; X-IronPort-AV: E=McAfee;i="6600,9927,10803"; a="371188863" X-IronPort-AV: E=Sophos;i="6.01,174,1684825200"; d="scan'208";a="371188863" Received: from fmsmga004.fm.intel.com ([10.253.24.48]) by fmsmga104.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 15 Aug 2023 06:51:32 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10803"; a="803827030" X-IronPort-AV: E=Sophos;i="6.01,174,1684825200"; d="scan'208";a="803827030" Received: from smile.fi.intel.com ([10.237.72.54]) by fmsmga004.fm.intel.com with ESMTP; 15 Aug 2023 06:51:31 -0700 Received: from andy by smile.fi.intel.com with local (Exim 4.96) (envelope-from ) id 1qVuSI-003wZW-1S; Tue, 15 Aug 2023 16:51:30 +0300 Date: Tue, 15 Aug 2023 16:51:30 +0300 From: Andy Shevchenko To: Takashi Iwai Cc: alsa-devel@alsa-project.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH 03/25] ALSA: core: Add memory copy helpers between iov_iter and iomem Message-ID: References: <20230814115523.15279-1-tiwai@suse.de> <20230814115523.15279-4-tiwai@suse.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20230814115523.15279-4-tiwai@suse.de> Organization: Intel Finland Oy - BIC 0357606-4 - Westendinkatu 7, 02160 Espoo Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Aug 14, 2023 at 01:55:01PM +0200, Takashi Iwai wrote: > Add two more helpers for copying memory between iov_iter and iomem, > which will be used by the new PCM copy ops in a few drivers. > The existing helpers became wrappers of those now. > > Note that copy_from/to_iter() returns the copied bytes, hence the > error condition is inverted from copy_from/to_user(). ... > - return copy_to_user(dst, (const void __force*)src, count) ? -EFAULT : 0; > + return !copy_to_iter((const void __force *)src, count, dst) ? -EFAULT : 0; Inverted means, I believe, this return copy_to_iter((const void __force *)src, count, dst) == count ? 0 : -EFAULT; as far as I understand the idea behind the copy_to_user() return value. Ditto for other cases. -- With Best Regards, Andy Shevchenko