From patchwork Wed Mar 30 16:14:16 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Boris BREZILLON X-Patchwork-Id: 8700091 Return-Path: X-Original-To: patchwork-linux-arm@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork1.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.136]) by patchwork1.web.kernel.org (Postfix) with ESMTP id 978AB9F44D for ; Wed, 30 Mar 2016 16:30:01 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 0A4392038A for ; Wed, 30 Mar 2016 16:30:00 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.9]) (using TLSv1.2 with cipher AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 3A6B220221 for ; Wed, 30 Mar 2016 16:29:58 +0000 (UTC) Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.80.1 #2 (Red Hat Linux)) id 1alIyG-0003qv-IT; Wed, 30 Mar 2016 16:27:52 +0000 Received: from down.free-electrons.com ([37.187.137.238] helo=mail.free-electrons.com) by bombadil.infradead.org with esmtp (Exim 4.80.1 #2 (Red Hat Linux)) id 1alImQ-0007uu-KM; Wed, 30 Mar 2016 16:15:45 +0000 Received: by mail.free-electrons.com (Postfix, from userid 110) id A9E331818; Wed, 30 Mar 2016 18:15:17 +0200 (CEST) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Spam-Level: X-Spam-Status: No, score=-5.2 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_MED, RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 Received: from localhost.localdomain (LMontsouris-657-1-184-87.w90-63.abo.wanadoo.fr [90.63.216.87]) by mail.free-electrons.com (Postfix) with ESMTPSA id C62F3141; Wed, 30 Mar 2016 18:15:06 +0200 (CEST) From: Boris Brezillon To: David Woodhouse , Brian Norris , linux-mtd@lists.infradead.org, Boris Brezillon , Richard Weinberger Subject: [PATCH v5 01/50] mtd: add mtd_ooblayout_xxx() helper functions Date: Wed, 30 Mar 2016 18:14:16 +0200 Message-Id: <1459354505-32551-2-git-send-email-boris.brezillon@free-electrons.com> X-Mailer: git-send-email 2.5.0 In-Reply-To: <1459354505-32551-1-git-send-email-boris.brezillon@free-electrons.com> References: <1459354505-32551-1-git-send-email-boris.brezillon@free-electrons.com> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20160330_091539_097848_C4CEC65F X-CRM114-Status: GOOD ( 22.35 ) X-Spam-Score: -2.9 (--) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.20 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: linux-mips@linux-mips.org, Krzysztof Kozlowski , Harvey Hunt , Nicolas Ferre , Stefan Agner , linux-sunxi@googlegroups.com, Alexandre Belloni , punnaiah choudary kalluri , Robert Jarzmik , devel@driverdev.osuosl.org, Archit Taneja , linux-samsung-soc@vger.kernel.org, Kamal Dasu , Josh Wu , Chen-Yu Tsai , Kukjin Kim , bcm-kernel-feedback-list@broadcom.com, Ezequiel Garcia , Huang Shijie , Jean-Christophe Plagniol-Villard , Haojian Zhuang , Han Xu , linux-arm-kernel@lists.infradead.org, Priit Laes , Greg Kroah-Hartman , linux-kernel@vger.kernel.org, Ralf Baechle , Wenyou Yang , Kyungmin Park , linux-api@vger.kernel.org, Maxime Ripard , Daniel Mack MIME-Version: 1.0 Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Virus-Scanned: ClamAV using ClamSMTP In order to make the ecclayout definition completely dynamic we need to rework the way the OOB layout are defined and iterated. Create a few mtd_ooblayout_xxx() helpers to ease OOB bytes manipulation and hide ecclayout internals to their users. Signed-off-by: Boris Brezillon --- drivers/mtd/mtdcore.c | 400 ++++++++++++++++++++++++++++++++++++++++++++++++ include/linux/mtd/mtd.h | 33 ++++ 2 files changed, 433 insertions(+) diff --git a/drivers/mtd/mtdcore.c b/drivers/mtd/mtdcore.c index 3096251..9fc278a 100644 --- a/drivers/mtd/mtdcore.c +++ b/drivers/mtd/mtdcore.c @@ -997,6 +997,406 @@ int mtd_read_oob(struct mtd_info *mtd, loff_t from, struct mtd_oob_ops *ops) } EXPORT_SYMBOL_GPL(mtd_read_oob); +/** + * mtd_ooblayout_ecc - Get the OOB region definition of a specific ECC section + * @mtd: MTD device structure + * @section: ECC section. Depending on the layout you may have all the ECC + * bytes stored in a single contiguous section, or one section + * per ECC chunk (and sometime several sections for a single ECC + * ECC chunk) + * @oobecc: OOB region struct filled with the appropriate ECC position + * information + * + * This functions return ECC section information in the OOB area. I you want + * to get all the ECC bytes information, then you should call + * mtd_ooblayout_ecc(mtd, section++, oobecc) until it returns -ERANGE. + * + * Returns zero on success, a negative error code otherwise. + */ +int mtd_ooblayout_ecc(struct mtd_info *mtd, int section, + struct mtd_oob_region *oobecc) +{ + int eccbyte = 0, cursection = 0, length = 0, eccpos = 0; + + memset(oobecc, 0, sizeof(*oobecc)); + + if (!mtd || section < 0) + return -EINVAL; + + if (!mtd->ecclayout) + return -ENOTSUPP; + + /* + * This logic allows us to reuse the ->ecclayout information and + * expose them as ECC regions (as done for the OOB free regions). + * + * TODO: this should be dropped as soon as we get rid of the + * ->ecclayout field. + */ + for (eccbyte = 0; eccbyte < mtd->ecclayout->eccbytes; eccbyte++) { + eccpos = mtd->ecclayout->eccpos[eccbyte]; + + if (eccbyte < mtd->ecclayout->eccbytes - 1) { + int neccpos = mtd->ecclayout->eccpos[eccbyte + 1]; + + if (eccpos + 1 == neccpos) { + length++; + continue; + } + } + + if (section == cursection) + break; + + length = 0; + cursection++; + } + + if (cursection != section || eccbyte >= mtd->ecclayout->eccbytes) + return -ERANGE; + + oobecc->length = length + 1; + oobecc->offset = eccpos - length; + + return 0; +} +EXPORT_SYMBOL_GPL(mtd_ooblayout_ecc); + +/** + * mtd_ooblayout_free - Get the OOB region definition of a specific free + * section + * @mtd: MTD device structure + * @section: Free section you are interested in. Depending on the layout + * you may have all the free bytes stored in a single contiguous + * section, or one section per ECC chunk plus an extra section + * for the remaining bytes (or other funky layout). + * @oobfree: OOB region struct filled with the appropriate free position + * information + * + * This functions return free bytes position in the OOB area. I you want + * to get all the free bytes information, then you should call + * mtd_ooblayout_free(mtd, section++, oobfree) until it returns -ERANGE. + * + * Returns zero on success, a negative error code otherwise. + */ +int mtd_ooblayout_free(struct mtd_info *mtd, int section, + struct mtd_oob_region *oobfree) +{ + memset(oobfree, 0, sizeof(*oobfree)); + + if (!mtd || section < 0) + return -EINVAL; + + if (!mtd->ecclayout) + return -ENOTSUPP; + + if (section >= MTD_MAX_OOBFREE_ENTRIES_LARGE) + return -ERANGE; + + oobfree->offset = mtd->ecclayout->oobfree[section].offset; + oobfree->length = mtd->ecclayout->oobfree[section].length; + + return 0; +} +EXPORT_SYMBOL_GPL(mtd_ooblayout_free); + +/** + * mtd_ooblayout_find_region - Find the region attached to a specific byte + * @mtd: mtd info structure + * @byte: the byte we are searching for + * @sectionp: pointer where the section id will be stored + * @oobregion: used to retrieve the ECC position + * @iter: iterator function. Should be either mtd_ooblayout_free or + * mtd_ooblayout_ecc depending on the region type you're searching for + * + * This functions returns the section id and oobregion information of a + * specific byte. For example, say you want to know where the 4th ECC byte is + * stored, you'll use: + * + * mtd_ooblayout_find_region(mtd, 3, §ion, &oobregion, mtd_ooblayout_ecc); + * + * Returns zero on success, a negative error code otherwise. + */ +static int mtd_ooblayout_find_region(struct mtd_info *mtd, int byte, + int *sectionp, struct mtd_oob_region *oobregion, + int (*iter)(struct mtd_info *, + int section, + struct mtd_oob_region *oobregion)) +{ + int pos = 0, ret, section = 0; + + memset(oobregion, 0, sizeof(*oobregion)); + + while (1) { + ret = iter(mtd, section, oobregion); + if (ret) + return ret; + + if (pos + oobregion->length > byte) + break; + + pos += oobregion->length; + section++; + } + + /* + * Adjust region info to make it start at the beginning at the + * 'start' ECC byte. + */ + oobregion->offset += byte - pos; + oobregion->length -= byte - pos; + *sectionp = section; + + return 0; +} + +/** + * mtd_ooblayout_find_eccregion - Find the ECC region attached to a specific + * ECC byte + * @mtd: mtd info structure + * @eccbyte: the byte we are searching for + * @sectionp: pointer where the section id will be stored + * @oobregion: OOB region information + * + * Works like mtd_ooblayout_find_region() except it searches for a specific ECC + * byte. + * + * Returns zero on success, a negative error code otherwise. + */ +int mtd_ooblayout_find_eccregion(struct mtd_info *mtd, int eccbyte, + int *section, + struct mtd_oob_region *oobregion) +{ + return mtd_ooblayout_find_region(mtd, eccbyte, section, oobregion, + mtd_ooblayout_ecc); +} +EXPORT_SYMBOL_GPL(mtd_ooblayout_find_eccregion); + +/** + * mtd_ooblayout_get_bytes - Extract OOB bytes from the oob buffer + * @mtd: mtd info structure + * @buf: destination buffer to store OOB bytes + * @oobbuf: OOB buffer + * @start: first byte to retrieve + * @nbytes: number of bytes to retrieve + * @iter: section iterator + * + * Extract bytes attached to a specific category (ECC or free) + * from the OOB buffer and copy them into buf. + * + * Returns zero on success, a negative error code otherwise. + */ +static int mtd_ooblayout_get_bytes(struct mtd_info *mtd, u8 *buf, + const u8 *oobbuf, int start, int nbytes, + int (*iter)(struct mtd_info *, + int section, + struct mtd_oob_region *oobregion)) +{ + struct mtd_oob_region oobregion = { }; + int section = 0, ret; + + ret = mtd_ooblayout_find_region(mtd, start, §ion, + &oobregion, iter); + + while (!ret) { + int cnt; + + cnt = oobregion.length > nbytes ? nbytes : oobregion.length; + memcpy(buf, oobbuf + oobregion.offset, cnt); + buf += cnt; + nbytes -= cnt; + + if (!nbytes) + break; + + ret = iter(mtd, ++section, &oobregion); + } + + return ret; +} + +/** + * mtd_ooblayout_set_bytes - put OOB bytes into the oob buffer + * @mtd: mtd info structure + * @buf: source buffer to get OOB bytes from + * @oobbuf: OOB buffer + * @start: first OOB byte to set + * @nbytes: number of OOB bytes to set + * @iter: section iterator + * + * Fill the OOB buffer with data provided in buf. The category (ECC or free) + * is selected by passing the appropriate iterator. + * + * Returns zero on success, a negative error code otherwise. + */ +static int mtd_ooblayout_set_bytes(struct mtd_info *mtd, const u8 *buf, + u8 *oobbuf, int start, int nbytes, + int (*iter)(struct mtd_info *, + int section, + struct mtd_oob_region *oobregion)) +{ + struct mtd_oob_region oobregion = { }; + int section = 0, ret; + + ret = mtd_ooblayout_find_region(mtd, start, §ion, + &oobregion, iter); + + while (!ret) { + int cnt; + + cnt = oobregion.length > nbytes ? nbytes : oobregion.length; + memcpy(oobbuf + oobregion.offset, buf, cnt); + buf += cnt; + nbytes -= cnt; + + if (!nbytes) + break; + + ret = iter(mtd, ++section, &oobregion); + } + + return ret; +} + +/** + * mtd_ooblayout_count_bytes - count the number of bytes in a OOB category + * @mtd: mtd info structure + * @iter: category iterator + * + * Count the number of bytes in a given category. + * + * Returns a positive value on success, a negative error code otherwise. + */ +static int mtd_ooblayout_count_bytes(struct mtd_info *mtd, + int (*iter)(struct mtd_info *, + int section, + struct mtd_oob_region *oobregion)) +{ + struct mtd_oob_region oobregion = { }; + int section = 0, ret, nbytes = 0; + + while (1) { + ret = iter(mtd, section++, &oobregion); + if (ret) { + if (ret == -ERANGE) + ret = nbytes; + break; + } + + nbytes += oobregion.length; + } + + return ret; +} + +/** + * mtd_ooblayout_get_eccbytes - extract ECC bytes from the oob buffer + * @mtd: mtd info structure + * @eccbuf: destination buffer to store ECC bytes + * @oobbuf: OOB buffer + * @start: first ECC byte to retrieve + * @nbytes: number of ECC bytes to retrieve + * + * Works like mtd_ooblayout_get_bytes(), except it acts on ECC bytes. + * + * Returns zero on success, a negative error code otherwise. + */ +int mtd_ooblayout_get_eccbytes(struct mtd_info *mtd, u8 *eccbuf, + const u8 *oobbuf, int start, int nbytes) +{ + return mtd_ooblayout_get_bytes(mtd, eccbuf, oobbuf, start, nbytes, + mtd_ooblayout_ecc); +} +EXPORT_SYMBOL_GPL(mtd_ooblayout_get_eccbytes); + +/** + * mtd_ooblayout_set_eccbytes - set ECC bytes into the oob buffer + * @mtd: mtd info structure + * @eccbuf: source buffer to get ECC bytes from + * @oobbuf: OOB buffer + * @start: first ECC byte to set + * @nbytes: number of ECC bytes to set + * + * Works like mtd_ooblayout_set_bytes(), except it acts on ECC bytes. + * + * Returns zero on success, a negative error code otherwise. + */ +int mtd_ooblayout_set_eccbytes(struct mtd_info *mtd, const u8 *eccbuf, + u8 *oobbuf, int start, int nbytes) +{ + return mtd_ooblayout_set_bytes(mtd, eccbuf, oobbuf, start, nbytes, + mtd_ooblayout_ecc); +} +EXPORT_SYMBOL_GPL(mtd_ooblayout_set_eccbytes); + +/** + * mtd_ooblayout_get_databytes - extract data bytes from the oob buffer + * @mtd: mtd info structure + * @databuf: destination buffer to store ECC bytes + * @oobbuf: OOB buffer + * @start: first ECC byte to retrieve + * @nbytes: number of ECC bytes to retrieve + * + * Works like mtd_ooblayout_get_bytes(), except it acts on free bytes. + * + * Returns zero on success, a negative error code otherwise. + */ +int mtd_ooblayout_get_databytes(struct mtd_info *mtd, u8 *databuf, + const u8 *oobbuf, int start, int nbytes) +{ + return mtd_ooblayout_get_bytes(mtd, databuf, oobbuf, start, nbytes, + mtd_ooblayout_free); +} +EXPORT_SYMBOL_GPL(mtd_ooblayout_get_databytes); + +/** + * mtd_ooblayout_get_eccbytes - set data bytes into the oob buffer + * @mtd: mtd info structure + * @eccbuf: source buffer to get data bytes from + * @oobbuf: OOB buffer + * @start: first ECC byte to set + * @nbytes: number of ECC bytes to set + * + * Works like mtd_ooblayout_get_bytes(), except it acts on free bytes. + * + * Returns zero on success, a negative error code otherwise. + */ +int mtd_ooblayout_set_databytes(struct mtd_info *mtd, const u8 *databuf, + u8 *oobbuf, int start, int nbytes) +{ + return mtd_ooblayout_set_bytes(mtd, databuf, oobbuf, start, nbytes, + mtd_ooblayout_free); +} +EXPORT_SYMBOL_GPL(mtd_ooblayout_set_databytes); + +/** + * mtd_ooblayout_count_freebytes - count the number of free bytes in OOB + * @mtd: mtd info structure + * + * Works like mtd_ooblayout_count_bytes(), except it count free bytes. + * + * Returns zero on success, a negative error code otherwise. + */ +int mtd_ooblayout_count_freebytes(struct mtd_info *mtd) +{ + return mtd_ooblayout_count_bytes(mtd, mtd_ooblayout_free); +} +EXPORT_SYMBOL_GPL(mtd_ooblayout_count_freebytes); + +/** + * mtd_ooblayout_count_freebytes - count the number of ECC bytes in OOB + * @mtd: mtd info structure + * + * Works like mtd_ooblayout_count_bytes(), except it count ECC bytes. + * + * Returns zero on success, a negative error code otherwise. + */ +int mtd_ooblayout_count_eccbytes(struct mtd_info *mtd) +{ + return mtd_ooblayout_count_bytes(mtd, mtd_ooblayout_ecc); +} +EXPORT_SYMBOL_GPL(mtd_ooblayout_count_eccbytes); + /* * Method to access the protection register area, present in some flash * devices. The user data is one time programmable but the factory data is read diff --git a/include/linux/mtd/mtd.h b/include/linux/mtd/mtd.h index 7712721..b141f26 100644 --- a/include/linux/mtd/mtd.h +++ b/include/linux/mtd/mtd.h @@ -108,6 +108,21 @@ struct nand_ecclayout { struct nand_oobfree oobfree[MTD_MAX_OOBFREE_ENTRIES_LARGE]; }; +/** + * struct mtd_oob_region - oob region definition + * @offset: region offset + * @length: region length + * + * This structure describes a region of the OOB area, and is used + * to retrieve ECC or free bytes sections. + * Each section is defined by an offset within the OOB area and a + * length. + */ +struct mtd_oob_region { + u32 offset; + u32 length; +}; + struct module; /* only needed for owner field in mtd_info */ struct mtd_info { @@ -253,6 +268,24 @@ struct mtd_info { int usecount; }; +int mtd_ooblayout_ecc(struct mtd_info *mtd, int section, + struct mtd_oob_region *oobecc); +int mtd_ooblayout_find_eccregion(struct mtd_info *mtd, int eccbyte, + int *section, + struct mtd_oob_region *oobregion); +int mtd_ooblayout_get_eccbytes(struct mtd_info *mtd, u8 *eccbuf, + const u8 *oobbuf, int start, int nbytes); +int mtd_ooblayout_set_eccbytes(struct mtd_info *mtd, const u8 *eccbuf, + u8 *oobbuf, int start, int nbytes); +int mtd_ooblayout_free(struct mtd_info *mtd, int section, + struct mtd_oob_region *oobfree); +int mtd_ooblayout_get_databytes(struct mtd_info *mtd, u8 *databuf, + const u8 *oobbuf, int start, int nbytes); +int mtd_ooblayout_set_databytes(struct mtd_info *mtd, const u8 *databuf, + u8 *oobbuf, int start, int nbytes); +int mtd_ooblayout_count_freebytes(struct mtd_info *mtd); +int mtd_ooblayout_count_eccbytes(struct mtd_info *mtd); + static inline void mtd_set_of_node(struct mtd_info *mtd, struct device_node *np) {