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 AC01AC433F5 for ; Mon, 20 Dec 2021 13:00:25 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232051AbhLTNAZ (ORCPT ); Mon, 20 Dec 2021 08:00:25 -0500 Received: from first.geanix.com ([116.203.34.67]:37712 "EHLO first.geanix.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231964AbhLTNAX (ORCPT ); Mon, 20 Dec 2021 08:00:23 -0500 Received: from zen.. (unknown [185.17.218.86]) by first.geanix.com (Postfix) with ESMTPSA id 9A8BBE1C31; Mon, 20 Dec 2021 13:00:21 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=geanix.com; s=first; t=1640005221; bh=hvwCkqPjGD5frgBR39knvzzCIahAUPKeCdgKyX7cVOQ=; h=From:To:Cc:Subject:Date; b=cqfJn+qW30EC3BAsTTNcCzSDvgyeyRsPHqWrXDvcYRy0y52FOsOo83CBD8rvusqff mMxZ8LcDmaKuOYLcRQyByFkVeIhtOTQhYgUCnaDN4z4PGjEvdubXVT1KrPkTF0zOK4 7ix5/6taFXy+IOuMpAFfdWsH9bsjvUDHWAFvyknBkefOe1uZr0zWFF0N1jZNJ2rinO ICszJRR4mkRTyOYjn6WE59WBcEbCrh1GSb1D1LI5W3YWFZF1HIzwzMq6BBUDkBcThW YCW2ZzTj+mZ5IVCJ1A3vHR5QK9yk3DnEmkzVdWMpHuQ+mzX29C7Z3XPyOIw8EiHhI7 uMN5BkQa/w69w== From: Sean Nyekjaer To: Miquel Raynal , Richard Weinberger , Vignesh Raghavendra , Boris Brezillon Cc: Sean Nyekjaer , linux-mtd@lists.infradead.org, linux-kernel@vger.kernel.org Subject: [PATCH] mtd: rawnand: protect access to rawnand devices while in suspend Date: Mon, 20 Dec 2021 14:00:15 +0100 Message-Id: <20211220130015.3630975-1-sean@geanix.com> X-Mailer: git-send-email 2.34.1 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Prevent rawnend access while in a suspended state. Commit 013e6292aaf5 ("mtd: rawnand: Simplify the locking") allows the rawnand layer to return errors rather than waiting in a blocking wait. Tested on a iMX6ULL. Fixes: 013e6292aaf5 ("mtd: rawnand: Simplify the locking") Signed-off-by: Sean Nyekjaer --- Follow-up on discussion in: https://lkml.org/lkml/2021/10/4/41 https://lkml.org/lkml/2021/10/11/435 https://lkml.org/lkml/2021/10/20/184 https://lkml.org/lkml/2021/10/25/288 https://lkml.org/lkml/2021/10/26/55 https://lkml.org/lkml/2021/11/2/352 drivers/mtd/nand/raw/nand_base.c | 42 +++++++++++++++----------------- include/linux/mtd/rawnand.h | 1 + 2 files changed, 20 insertions(+), 23 deletions(-) diff --git a/drivers/mtd/nand/raw/nand_base.c b/drivers/mtd/nand/raw/nand_base.c index b3a9bc08b4bb..eb4ec9a42d49 100644 --- a/drivers/mtd/nand/raw/nand_base.c +++ b/drivers/mtd/nand/raw/nand_base.c @@ -338,16 +338,19 @@ static int nand_isbad_bbm(struct nand_chip *chip, loff_t ofs) * * Return: -EBUSY if the chip has been suspended, 0 otherwise */ -static int nand_get_device(struct nand_chip *chip) +static void nand_get_device(struct nand_chip *chip) { - mutex_lock(&chip->lock); - if (chip->suspended) { + /* Wait until the device is resumed. */ + while (1) { + mutex_lock(&chip->lock); + if (!chip->suspended) { + mutex_lock(&chip->controller->lock); + return; + } mutex_unlock(&chip->lock); - return -EBUSY; - } - mutex_lock(&chip->controller->lock); - return 0; + wait_event(chip->resume_wq, !chip->suspended); + } } /** @@ -576,9 +579,7 @@ static int nand_block_markbad_lowlevel(struct nand_chip *chip, loff_t ofs) nand_erase_nand(chip, &einfo, 0); /* Write bad block marker to OOB */ - ret = nand_get_device(chip); - if (ret) - return ret; + nand_get_device(chip); ret = nand_markbad_bbm(chip, ofs); nand_release_device(chip); @@ -3759,9 +3760,7 @@ static int nand_read_oob(struct mtd_info *mtd, loff_t from, ops->mode != MTD_OPS_RAW) return -ENOTSUPP; - ret = nand_get_device(chip); - if (ret) - return ret; + nand_get_device(chip); if (!ops->datbuf) ret = nand_do_read_oob(chip, from, ops); @@ -4352,9 +4351,7 @@ static int nand_write_oob(struct mtd_info *mtd, loff_t to, ops->retlen = 0; - ret = nand_get_device(chip); - if (ret) - return ret; + nand_get_device(chip); switch (ops->mode) { case MTD_OPS_PLACE_OOB: @@ -4414,9 +4411,7 @@ int nand_erase_nand(struct nand_chip *chip, struct erase_info *instr, return -EIO; /* Grab the lock and see if the device is available */ - ret = nand_get_device(chip); - if (ret) - return ret; + nand_get_device(chip); /* Shift to get first page */ page = (int)(instr->addr >> chip->page_shift); @@ -4503,7 +4498,7 @@ static void nand_sync(struct mtd_info *mtd) pr_debug("%s: called\n", __func__); /* Grab the lock and see if the device is available */ - WARN_ON(nand_get_device(chip)); + nand_get_device(chip); /* Release it and go back */ nand_release_device(chip); } @@ -4520,9 +4515,7 @@ static int nand_block_isbad(struct mtd_info *mtd, loff_t offs) int ret; /* Select the NAND device */ - ret = nand_get_device(chip); - if (ret) - return ret; + nand_get_device(chip); nand_select_target(chip, chipnr); @@ -4593,6 +4586,8 @@ static void nand_resume(struct mtd_info *mtd) __func__); } mutex_unlock(&chip->lock); + + wake_up_all(&chip->resume_wq); } /** @@ -5370,6 +5365,7 @@ static int nand_scan_ident(struct nand_chip *chip, unsigned int maxchips, chip->cur_cs = -1; mutex_init(&chip->lock); + init_waitqueue_head(&chip->resume_wq); /* Enforce the right timings for reset/detection */ chip->current_interface_config = nand_get_reset_interface_config(); diff --git a/include/linux/mtd/rawnand.h b/include/linux/mtd/rawnand.h index b2f9dd3cbd69..248054560581 100644 --- a/include/linux/mtd/rawnand.h +++ b/include/linux/mtd/rawnand.h @@ -1294,6 +1294,7 @@ struct nand_chip { /* Internals */ struct mutex lock; unsigned int suspended : 1; + wait_queue_head_t resume_wq; int cur_cs; int read_retries; struct nand_secure_region *secure_regions; -- 2.34.1 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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id A065BC433F5 for ; Mon, 20 Dec 2021 13:01:14 +0000 (UTC) DKIM-Signature: v=1; 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(unknown [185.17.218.86]) by first.geanix.com (Postfix) with ESMTPSA id 9A8BBE1C31; Mon, 20 Dec 2021 13:00:21 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=geanix.com; s=first; t=1640005221; bh=hvwCkqPjGD5frgBR39knvzzCIahAUPKeCdgKyX7cVOQ=; h=From:To:Cc:Subject:Date; b=cqfJn+qW30EC3BAsTTNcCzSDvgyeyRsPHqWrXDvcYRy0y52FOsOo83CBD8rvusqff mMxZ8LcDmaKuOYLcRQyByFkVeIhtOTQhYgUCnaDN4z4PGjEvdubXVT1KrPkTF0zOK4 7ix5/6taFXy+IOuMpAFfdWsH9bsjvUDHWAFvyknBkefOe1uZr0zWFF0N1jZNJ2rinO ICszJRR4mkRTyOYjn6WE59WBcEbCrh1GSb1D1LI5W3YWFZF1HIzwzMq6BBUDkBcThW YCW2ZzTj+mZ5IVCJ1A3vHR5QK9yk3DnEmkzVdWMpHuQ+mzX29C7Z3XPyOIw8EiHhI7 uMN5BkQa/w69w== From: Sean Nyekjaer To: Miquel Raynal , Richard Weinberger , Vignesh Raghavendra , Boris Brezillon Cc: Sean Nyekjaer , linux-mtd@lists.infradead.org, linux-kernel@vger.kernel.org Subject: [PATCH] mtd: rawnand: protect access to rawnand devices while in suspend Date: Mon, 20 Dec 2021 14:00:15 +0100 Message-Id: <20211220130015.3630975-1-sean@geanix.com> X-Mailer: git-send-email 2.34.1 MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20211220_050028_166022_2529AC09 X-CRM114-Status: GOOD ( 16.40 ) X-BeenThere: linux-mtd@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: Linux MTD discussion mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-mtd" Errors-To: linux-mtd-bounces+linux-mtd=archiver.kernel.org@lists.infradead.org Prevent rawnend access while in a suspended state. Commit 013e6292aaf5 ("mtd: rawnand: Simplify the locking") allows the rawnand layer to return errors rather than waiting in a blocking wait. Tested on a iMX6ULL. Fixes: 013e6292aaf5 ("mtd: rawnand: Simplify the locking") Signed-off-by: Sean Nyekjaer --- Follow-up on discussion in: https://lkml.org/lkml/2021/10/4/41 https://lkml.org/lkml/2021/10/11/435 https://lkml.org/lkml/2021/10/20/184 https://lkml.org/lkml/2021/10/25/288 https://lkml.org/lkml/2021/10/26/55 https://lkml.org/lkml/2021/11/2/352 drivers/mtd/nand/raw/nand_base.c | 42 +++++++++++++++----------------- include/linux/mtd/rawnand.h | 1 + 2 files changed, 20 insertions(+), 23 deletions(-) diff --git a/drivers/mtd/nand/raw/nand_base.c b/drivers/mtd/nand/raw/nand_base.c index b3a9bc08b4bb..eb4ec9a42d49 100644 --- a/drivers/mtd/nand/raw/nand_base.c +++ b/drivers/mtd/nand/raw/nand_base.c @@ -338,16 +338,19 @@ static int nand_isbad_bbm(struct nand_chip *chip, loff_t ofs) * * Return: -EBUSY if the chip has been suspended, 0 otherwise */ -static int nand_get_device(struct nand_chip *chip) +static void nand_get_device(struct nand_chip *chip) { - mutex_lock(&chip->lock); - if (chip->suspended) { + /* Wait until the device is resumed. */ + while (1) { + mutex_lock(&chip->lock); + if (!chip->suspended) { + mutex_lock(&chip->controller->lock); + return; + } mutex_unlock(&chip->lock); - return -EBUSY; - } - mutex_lock(&chip->controller->lock); - return 0; + wait_event(chip->resume_wq, !chip->suspended); + } } /** @@ -576,9 +579,7 @@ static int nand_block_markbad_lowlevel(struct nand_chip *chip, loff_t ofs) nand_erase_nand(chip, &einfo, 0); /* Write bad block marker to OOB */ - ret = nand_get_device(chip); - if (ret) - return ret; + nand_get_device(chip); ret = nand_markbad_bbm(chip, ofs); nand_release_device(chip); @@ -3759,9 +3760,7 @@ static int nand_read_oob(struct mtd_info *mtd, loff_t from, ops->mode != MTD_OPS_RAW) return -ENOTSUPP; - ret = nand_get_device(chip); - if (ret) - return ret; + nand_get_device(chip); if (!ops->datbuf) ret = nand_do_read_oob(chip, from, ops); @@ -4352,9 +4351,7 @@ static int nand_write_oob(struct mtd_info *mtd, loff_t to, ops->retlen = 0; - ret = nand_get_device(chip); - if (ret) - return ret; + nand_get_device(chip); switch (ops->mode) { case MTD_OPS_PLACE_OOB: @@ -4414,9 +4411,7 @@ int nand_erase_nand(struct nand_chip *chip, struct erase_info *instr, return -EIO; /* Grab the lock and see if the device is available */ - ret = nand_get_device(chip); - if (ret) - return ret; + nand_get_device(chip); /* Shift to get first page */ page = (int)(instr->addr >> chip->page_shift); @@ -4503,7 +4498,7 @@ static void nand_sync(struct mtd_info *mtd) pr_debug("%s: called\n", __func__); /* Grab the lock and see if the device is available */ - WARN_ON(nand_get_device(chip)); + nand_get_device(chip); /* Release it and go back */ nand_release_device(chip); } @@ -4520,9 +4515,7 @@ static int nand_block_isbad(struct mtd_info *mtd, loff_t offs) int ret; /* Select the NAND device */ - ret = nand_get_device(chip); - if (ret) - return ret; + nand_get_device(chip); nand_select_target(chip, chipnr); @@ -4593,6 +4586,8 @@ static void nand_resume(struct mtd_info *mtd) __func__); } mutex_unlock(&chip->lock); + + wake_up_all(&chip->resume_wq); } /** @@ -5370,6 +5365,7 @@ static int nand_scan_ident(struct nand_chip *chip, unsigned int maxchips, chip->cur_cs = -1; mutex_init(&chip->lock); + init_waitqueue_head(&chip->resume_wq); /* Enforce the right timings for reset/detection */ chip->current_interface_config = nand_get_reset_interface_config(); diff --git a/include/linux/mtd/rawnand.h b/include/linux/mtd/rawnand.h index b2f9dd3cbd69..248054560581 100644 --- a/include/linux/mtd/rawnand.h +++ b/include/linux/mtd/rawnand.h @@ -1294,6 +1294,7 @@ struct nand_chip { /* Internals */ struct mutex lock; unsigned int suspended : 1; + wait_queue_head_t resume_wq; int cur_cs; int read_retries; struct nand_secure_region *secure_regions; -- 2.34.1 ______________________________________________________ Linux MTD discussion mailing list http://lists.infradead.org/mailman/listinfo/linux-mtd/