Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932822Ab3CMNMd (ORCPT ); Wed, 13 Mar 2013 09:12:33 -0400 Received: from mga14.intel.com ([143.182.124.37]:59710 "EHLO mga14.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932295Ab3CMNMc (ORCPT ); Wed, 13 Mar 2013 09:12:32 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="4.84,837,1355126400"; d="scan'208";a="269912713" Message-ID: <1363180395.11441.57.camel@sauron.fi.intel.com> Subject: Re: [PATCH V4 1/3] mtd: add new fields to nand_flash_dev{} From: Artem Bityutskiy Reply-To: artem.bityutskiy@linux.intel.com To: Huang Shijie Cc: Huang Shijie , dwmw2@infradead.org, computersforpeace@gmail.com, linux-mtd@lists.infradead.org, linux-kernel@vger.kernel.org Date: Wed, 13 Mar 2013 15:13:15 +0200 In-Reply-To: References: <1362653364-29993-1-git-send-email-b32955@freescale.com> <1362653364-29993-2-git-send-email-b32955@freescale.com> <1363172096.11441.11.camel@sauron.fi.intel.com> Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.6.3 (3.6.3-2.fc18) Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1719 Lines: 44 On Wed, 2013-03-13 at 21:04 +0800, Huang Shijie wrote: > On Wed, Mar 13, 2013 at 6:54 PM, Artem Bityutskiy > wrote: > > On Thu, 2013-03-07 at 18:49 +0800, Huang Shijie wrote: > >> diff --git a/include/linux/mtd/nand.h b/include/linux/mtd/nand.h > >> index 591eeeb..f0a9d93 100644 > >> --- a/include/linux/mtd/nand.h > >> +++ b/include/linux/mtd/nand.h > >> @@ -578,6 +578,8 @@ struct nand_chip { > >> * @erasesize: eraseblock size in bytes (determined from the extended ID if 0) > >> * @chipsize: total chip size in MiB > >> * @options: stores various chip bit options > >> + * @id_len: The valid length of the @id. > >> + * @oobsize: OOB size > >> */ > >> struct nand_flash_dev { > >> char *name; > >> @@ -592,6 +594,8 @@ struct nand_flash_dev { > >> unsigned long chipsize; > >> unsigned long erasesize; > >> unsigned long options; > >> + unsigned long id_len; > >> + unsigned long oobsize; > >> }; > > > > Why are these of type 'long', which is 64 bits in 64-bit architectures, > > which seems to be unnecessarily big. Wouldn't 'unsigned int' be enough? > > > Frankly speaking, "uint16_t" is enough. > "unsigned int" is too long for both the fields. Adding a single uint16_t is useless because GCC will pad it to 32 bits anyway. I send a patch which turns all the longs to ints. Just add another int. And yes, do not add id_len unless you need it. Thanks! -- Best Regards, Artem Bityutskiy -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/