From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758079Ab2HQOht (ORCPT ); Fri, 17 Aug 2012 10:37:49 -0400 Received: from mail-wi0-f178.google.com ([209.85.212.178]:51378 "EHLO mail-wi0-f178.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758041Ab2HQOgB (ORCPT ); Fri, 17 Aug 2012 10:36:01 -0400 From: Richard Genoud To: Artem Bityutskiy Cc: Shmulik Ladkani , linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, linux-mtd@lists.infradead.org, Richard Genoud Subject: [PATCH 7/8] UBI: add ioctl for max_beb_per1024 Date: Fri, 17 Aug 2012 16:35:23 +0200 Message-Id: <1345214124-5478-8-git-send-email-richard.genoud@gmail.com> X-Mailer: git-send-email 1.7.2.5 In-Reply-To: <1345214124-5478-1-git-send-email-richard.genoud@gmail.com> References: <1345214124-5478-1-git-send-email-richard.genoud@gmail.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org This patch provides the possibility to adjust the "maximum expected number of bad blocks per 1024 blocks" (max_beb_per1024) for each mtd device from UBI_IOCATT ioctl. The majority of NAND devices have their max_beb_per1024 equal to 20, but sometimes it's more. We already could adjust that via a kernel parameter, now we can also use UBI_IOCATT ioctl: struct ubi_attach_req { __s32 ubi_num; __s32 mtd_num; __s32 vid_hdr_offset; __u8 max_beb_per1024; __s8 padding[11]; }; Signed-off-by: Richard Genoud --- drivers/mtd/ubi/Kconfig | 3 ++- drivers/mtd/ubi/cdev.c | 2 +- include/mtd/ubi-user.h | 19 ++++++++++++++++++- 3 files changed, 21 insertions(+), 3 deletions(-) diff --git a/drivers/mtd/ubi/Kconfig b/drivers/mtd/ubi/Kconfig index 8b67bac..56531a7 100644 --- a/drivers/mtd/ubi/Kconfig +++ b/drivers/mtd/ubi/Kconfig @@ -51,7 +51,8 @@ config MTD_UBI_BEB_LIMIT MTD partitions of the same size, UBI will reserve 40 eraseblocks when attaching a partition. - This option can be overridden by the kernel parameter ubi.mtd. + This option can be overridden by the kernel parameter ubi.mtd and the + ioctl UBI_IOCATT. Leave the default value if unsure. diff --git a/drivers/mtd/ubi/cdev.c b/drivers/mtd/ubi/cdev.c index 619f914..7885dc0 100644 --- a/drivers/mtd/ubi/cdev.c +++ b/drivers/mtd/ubi/cdev.c @@ -1011,7 +1011,7 @@ static long ctrl_cdev_ioctl(struct file *file, unsigned int cmd, */ mutex_lock(&ubi_devices_mutex); err = ubi_attach_mtd_dev(mtd, req.ubi_num, req.vid_hdr_offset, - CONFIG_MTD_UBI_BEB_LIMIT); + req.max_beb_per1024); mutex_unlock(&ubi_devices_mutex); if (err < 0) put_mtd_device(mtd); diff --git a/include/mtd/ubi-user.h b/include/mtd/ubi-user.h index 8787349..8168d9b 100644 --- a/include/mtd/ubi-user.h +++ b/include/mtd/ubi-user.h @@ -222,6 +222,7 @@ enum { * @ubi_num: UBI device number to create * @mtd_num: MTD device number to attach * @vid_hdr_offset: VID header offset (use defaults if %0) + * @max_beb_per1024: Maximum expected bad eraseblocks per 1024 eraseblocks * @padding: reserved for future, not used, has to be zeroed * * This data structure is used to specify MTD device UBI has to attach and the @@ -245,12 +246,28 @@ enum { * be 2KiB-64 bytes = 1984. Note, that this position is not even 512-bytes * aligned, which is OK, as UBI is clever enough to realize this is 4th * sub-page of the first page and add needed padding. + * + * The @max_beb_per1024 is the maximum bad eraseblocks UBI expects on the ubi + * device per 1024 eraseblocks. + * This value is often given in an other form in the NAND datasheet (min NVB + * i.e. minimal number of valid blocks). The maximum expected bad eraseblocks + * per 1024 is then: + * 1024 * (1 - MinNVB / MaxNVB) + * Which gives 20 for most NAND devices. + * This limit is used in order to derive amount of eraseblock UBI reserves for + * handling new bad blocks. + * If the device has more bad eraseblocks than this limit, UBI does not reserve + * any physical eraseblocks for new bad eraseblocks, but attempts to use + * available eraseblocks (if any). + * The accepted range is 0-255. If 0 is given, the default kernel config value + * CONFIG_MTD_UBI_BEB_LIMIT will be used for compatibility. */ struct ubi_attach_req { __s32 ubi_num; __s32 mtd_num; __s32 vid_hdr_offset; - __s8 padding[12]; + __u8 max_beb_per1024; + __s8 padding[11]; }; /** -- 1.7.2.5