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 mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 47BEDC433EF for ; Wed, 20 Oct 2021 08:58:24 +0000 (UTC) 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 mail.kernel.org (Postfix) with ESMTPS id D394C61004 for ; Wed, 20 Oct 2021 08:58:23 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org D394C61004 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=collabora.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: Message-ID:Subject:Cc:To:From:Date:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=h/zzIuE8qikA1OYNLHGGEE3kHK0sbiaP09NBOw6pUHM=; b=yFBbP5FAqPHCIN 3MfifhitjCNKo2XiPx+4TpYsfr5GrqviwCffLBmHGzJYv7bOO0wXMKtQ+ccUZPjUpU1nU6AjxZmpg tki4YIdMYIPBkwNbjl9AbeTEMCstji0AUzA9Hprd5OLjBDaR5saA1EisJyK6nrMIFTiZ+w0WoU2CD 6E5sMB9nTJAOrzxjr9KnndMTBxzWdpZUN2Qls/6i493C6y6P/ChmWb5mmLe1Y6MEZx4FEklbE7AQ0 21EcqfbW5VzzbBWU1gKufpMTOt8XgutwLZSR3/gzvRITNKCA39MuC3EJ/X4amMJRSndP3kvCmDmlo uHmgZis/Caut4zaukmsg==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1md7Pz-003uJ3-UW; Wed, 20 Oct 2021 08:57:51 +0000 Received: from bhuna.collabora.co.uk ([46.235.227.227]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1md7Pw-003uHf-I7 for linux-mtd@lists.infradead.org; Wed, 20 Oct 2021 08:57:50 +0000 Received: from localhost (unknown [IPv6:2a01:e0a:2c:6930:5cf4:84a1:2763:fe0d]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) (Authenticated sender: bbrezillon) by bhuna.collabora.co.uk (Postfix) with ESMTPSA id 1F4D81F43F4F; Wed, 20 Oct 2021 09:57:47 +0100 (BST) Date: Wed, 20 Oct 2021 10:57:43 +0200 From: Boris Brezillon To: Sean Nyekjaer Cc: Miquel Raynal , Richard Weinberger , Vignesh Raghavendra , Boris Brezillon , linux-mtd@lists.infradead.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v2 3/4] mtd: rawnand: remove suspended check Message-ID: <20211020105743.225d97f4@collabora.com> In-Reply-To: <20211020084534.2472305-4-sean@geanix.com> References: <20211020084534.2472305-1-sean@geanix.com> <20211020084534.2472305-4-sean@geanix.com> Organization: Collabora X-Mailer: Claws Mail 3.18.0 (GTK+ 2.24.33; x86_64-redhat-linux-gnu) MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20211020_015748_922363_5A40990A X-CRM114-Status: GOOD ( 32.45 ) 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 On Wed, 20 Oct 2021 10:45:33 +0200 Sean Nyekjaer wrote: > Access is protected in upper MTD layer when MTD devices are suspended. I think it deserves more explanation. > > Fixes: 013e6292aaf5 ("mtd: rawnand: Simplify the locking") This patch doesn't fix anything, things have been fixed in 'mtd: core: protect access to MTD devices while in suspend'. It's just a cleanup on top of it. > Reviewed-by: Miquel Raynal > Signed-off-by: Sean Nyekjaer > --- > drivers/mtd/nand/raw/nand_base.c | 52 ++++++++------------------------ > include/linux/mtd/rawnand.h | 5 +-- > 2 files changed, 14 insertions(+), 43 deletions(-) > > diff --git a/drivers/mtd/nand/raw/nand_base.c b/drivers/mtd/nand/raw/nand_base.c > index 3d6c6e880520..aa2874ae3c4a 100644 > --- a/drivers/mtd/nand/raw/nand_base.c > +++ b/drivers/mtd/nand/raw/nand_base.c > @@ -332,19 +332,11 @@ static int nand_isbad_bbm(struct nand_chip *chip, loff_t ofs) > * @chip: NAND chip structure > * > * Lock the device and its controller for exclusive access > - * > - * 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) { > - mutex_unlock(&chip->lock); > - return -EBUSY; > - } > mutex_lock(&chip->controller->lock); > - > - return 0; > } > > /** > @@ -573,10 +565,7 @@ 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); > } > @@ -3756,9 +3745,7 @@ 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); > @@ -4345,13 +4332,11 @@ static int nand_write_oob(struct mtd_info *mtd, loff_t to, > struct mtd_oob_ops *ops) > { > struct nand_chip *chip = mtd_to_nand(mtd); > - int ret; > + int ret = 0; > > ops->retlen = 0; > > - ret = nand_get_device(chip); > - if (ret) > - return ret; > + nand_get_device(chip); > > switch (ops->mode) { > case MTD_OPS_PLACE_OOB: > @@ -4410,10 +4395,8 @@ int nand_erase_nand(struct nand_chip *chip, struct erase_info *instr, > if (nand_region_is_secured(chip, instr->addr, instr->len)) > return -EIO; > > - /* Grab the lock and see if the device is available */ > - ret = nand_get_device(chip); > - if (ret) > - return ret; > + /* Grab the lock */ > + nand_get_device(chip); > > /* Shift to get first page */ > page = (int)(instr->addr >> chip->page_shift); > @@ -4499,8 +4482,8 @@ 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)); > + /* Grab the lock */ > + nand_get_device(chip); > /* Release it and go back */ > nand_release_device(chip); > } > @@ -4517,9 +4500,7 @@ 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); > > @@ -4565,8 +4546,6 @@ static int nand_suspend(struct mtd_info *mtd) > mutex_lock(&chip->lock); > if (chip->ops.suspend) > ret = chip->ops.suspend(chip); > - if (!ret) > - chip->suspended = 1; > mutex_unlock(&chip->lock); > > return ret; > @@ -4580,15 +4559,10 @@ static void nand_resume(struct mtd_info *mtd) > { > struct nand_chip *chip = mtd_to_nand(mtd); > > + > mutex_lock(&chip->lock); > - if (chip->suspended) { > - if (chip->ops.resume) > - chip->ops.resume(chip); > - chip->suspended = 0; > - } else { > - pr_err("%s called for a chip which is not in suspended state\n", > - __func__); > - } > + if (chip->ops.resume) > + chip->ops.resume(chip); > mutex_unlock(&chip->lock); > } > > diff --git a/include/linux/mtd/rawnand.h b/include/linux/mtd/rawnand.h > index b2f9dd3cbd69..1198a6548912 100644 > --- a/include/linux/mtd/rawnand.h > +++ b/include/linux/mtd/rawnand.h > @@ -1237,9 +1237,7 @@ struct nand_secure_region { > * @pagecache.page: Page number currently in the cache. -1 means no page is > * currently cached > * @buf_align: Minimum buffer alignment required by a platform > - * @lock: Lock protecting the suspended field. Also used to serialize accesses > - * to the NAND device > - * @suspended: Set to 1 when the device is suspended, 0 when it's not > + * @lock: Lock to serialize accesses to the NAND device > * @cur_cs: Currently selected target. -1 means no target selected, otherwise we > * should always have cur_cs >= 0 && cur_cs < nanddev_ntargets(). > * NAND Controller drivers should not modify this value, but they're > @@ -1293,7 +1291,6 @@ struct nand_chip { > > /* Internals */ > struct mutex lock; > - unsigned int suspended : 1; > int cur_cs; > int read_retries; > struct nand_secure_region *secure_regions; ______________________________________________________ Linux MTD discussion mailing list http://lists.infradead.org/mailman/listinfo/linux-mtd/