From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id C97CB657DA; Thu, 7 Mar 2024 09:51:44 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1709805104; cv=none; b=bjn5YwCHjY1Jgbe4TnCV8POtavat33ddtgxQIYJ54zlCFxRqyeGmE2Svc3y14GrWjOoltq3UVtT7Zf6HhhuLiy4dO8SsefW1VNE9jI8dgkLjrO4Az6v/KPXMZ+7bq5ZCayh8Ei6EFR+l1Wf/mWtnquhjU2gh8q5dn1x6WKdncYU= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1709805104; c=relaxed/simple; bh=y7Pe3kpgR5LWvQjFduDfVc1YDpdUKIE9eaLUuNrkxFA=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=IT/+gFnEbZRNuikyp3hTXRbqhAJ4XaIH4NCoTNVb+ziNqqfrhb0OvFHlnQlWfrin3gUBAYQn0NhpgS3fH2RKhuhcblMlqjZ8v5BtOp5WJNaRtHwk926gsqVaNKqSyevTCacTRJ66NCAvBeh797scStAYVHMdC9F7gBP31gnKNZU= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=VAVHRoQH; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="VAVHRoQH" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 03442C433F1; Thu, 7 Mar 2024 09:51:40 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1709805104; bh=y7Pe3kpgR5LWvQjFduDfVc1YDpdUKIE9eaLUuNrkxFA=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=VAVHRoQHjkUZ8vmfJkPg3Qjg/heJ7XlDwXRUEk7miFRh+Q1LacQifmD6s3npdie7J J9CxdcmmrK7Oba/7ZTAEJ32CTHOKWn+EQWRPXNozDI7F/7ERwBiwHg6KaEq2C8Tiwa ncAXbRKC3M1UYSIN7d7nc0zIEhbacM6r3/MtuhpiZs9rlWcQcHD2d7NFGxsR7kM9vD WyI0HDOHkgCx35kAKA76rUjtEupdfqe3dYXzsa3x8WpnyU/Y9qEbhEndyWjCIWuGvt w1NFxP+s7CO18yWRzCfO64a1K1ZrlM3s6/VtdtZmqkNentspZduQMIzi8LlctQSBQx FVY8lRiBfEDyg== Date: Thu, 7 Mar 2024 10:51:37 +0100 From: Niklas Cassel To: Igor Pylypiv Cc: Damien Le Moal , Hannes Reinecke , John Garry , Jason Yan , "James E.J. Bottomley" , "Martin K. Petersen" , Jack Wang , Xiang Chen , Artur Paszkiewicz , Bart Van Assche , TJ Adams , linux-ide@vger.kernel.org, linux-scsi@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v7 2/7] scsi: libsas: Define NCQ Priority sysfs attributes for SATA devices Message-ID: References: <20240306012226.3398927-1-ipylypiv@google.com> <20240306012226.3398927-3-ipylypiv@google.com> Precedence: bulk X-Mailing-List: linux-ide@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: On Wed, Mar 06, 2024 at 11:28:42AM -0800, Igor Pylypiv wrote: > On Wed, Mar 06, 2024 at 11:54:52AM +0100, Niklas Cassel wrote: > > On Tue, Mar 05, 2024 at 05:22:21PM -0800, Igor Pylypiv wrote: > > > Libata sysfs attributes cannot be used for libsas managed SATA devices > > > because the ata_port location is different for libsas. > > > > > > Defined sysfs attributes (visible for SATA devices only): > > > - /sys/block/sda/device/ncq_prio_enable > > > - /sys/block/sda/device/ncq_prio_supported > > > > > > The newly defined attributes will pass the correct ata_port to libata > > > helper functions. > > > > > > Reviewed-by: John Garry > > > Reviewed-by: Damien Le Moal > > > Reviewed-by: Jason Yan > > > Signed-off-by: Igor Pylypiv > > > --- > > > drivers/scsi/libsas/sas_ata.c | 94 +++++++++++++++++++++++++++++++++++ > > > include/scsi/sas_ata.h | 6 +++ > > > 2 files changed, 100 insertions(+) > > > > > > diff --git a/drivers/scsi/libsas/sas_ata.c b/drivers/scsi/libsas/sas_ata.c > > > index 12e2653846e3..04b0bd9a4e01 100644 > > > --- a/drivers/scsi/libsas/sas_ata.c > > > +++ b/drivers/scsi/libsas/sas_ata.c > > > @@ -964,3 +964,97 @@ int sas_execute_ata_cmd(struct domain_device *device, u8 *fis, int force_phy_id) > > > force_phy_id, &tmf_task); > > > } > > > EXPORT_SYMBOL_GPL(sas_execute_ata_cmd); > > > + > > > +static ssize_t sas_ncq_prio_supported_show(struct device *device, > > > + struct device_attribute *attr, > > > + char *buf) > > > +{ > > > + struct scsi_device *sdev = to_scsi_device(device); > > > + struct domain_device *ddev = sdev_to_domain_dev(sdev); > > > + bool supported; > > > + int rc; > > > + > > > + /* This attribute shall be visible for SATA devices only */ > > > + if (WARN_ON_ONCE(!dev_is_sata(ddev))) > > > + return -EINVAL; > > > > Like Hannes commented, I don't believe this is needed. > > > > The intention for the check is to serve as a fail-safe in case 'is_visible()' > callback gets incorrectly modified and stops hiding the sysfs attributes > for non-SATA devices. > > Just want to clarify should I remove the WARN_ON_ONCE and keep the fail-safe > check or should I get rid of the check completely and trust 'is_visible()' > to always hide the sysfs attributes for non-SATA devices? I think that you can remove both the WARN_ON_ONCE and the if (!dev_is_sata()). We usually don't keep code around "just in case someone modifies some other function sometime in the future". If someone changes is_visible() to remove the dev_is_sata() check, then they would introuce a bug. I don't see why anyone would change that, but if someone tried to remove that check from is_visible() anyway, I'm assuming that someone would catch it during code review. > > > > > > + > > > + rc = ata_ncq_prio_supported(ddev->sata_dev.ap, sdev, &supported); > > > + if (rc) > > > + return rc; > > > + > > > + return sysfs_emit(buf, "%d\n", supported); > > > +} > > > + > > > > While this is a bit different depending on file, the most common way is to > > have no blank link before the DEVICE_ATTR(). > > > > In "[PATCH 1/3] ata: libata-sata: Factor out NCQ Priority configuration helpers" > Damien asked to keep the blank link before the DEVICE_ATTR() in libata-sata.c. > > Non-prio sysfs attributes in libata-sata.c don't have blank lines > before DEVICE_ATTR() so I'm more inclined to remove the lines. > > I'm fine with either of ways, just want to get a consensus and make it > consistent for both libata-sata.c and sas_ata.c. While it is a bit different depending on file, it is slightly more common to no have a extra blank line before DEVICE_ATTR(): $ git grep -B 1 DEVICE_ATTR | grep "}" | wc -l 2167 $ git grep -B 1 DEVICE_ATTR | grep -- "c-$" | wc -l 1725 But I'm fine to keep it like it is, especially if Damien already had expresed a preference. Kind regards, Niklas > > > > > > +DEVICE_ATTR(ncq_prio_supported, S_IRUGO, sas_ncq_prio_supported_show, NULL); > > > + > > > +static ssize_t sas_ncq_prio_enable_show(struct device *device, > > > + struct device_attribute *attr, > > > + char *buf) > > > +{ > > > + struct scsi_device *sdev = to_scsi_device(device); > > > + struct domain_device *ddev = sdev_to_domain_dev(sdev); > > > + bool enabled; > > > + int rc; > > > + > > > + /* This attribute shall be visible for SATA devices only */ > > > + if (WARN_ON_ONCE(!dev_is_sata(ddev))) > > > + return -EINVAL; > > > + > > > + rc = ata_ncq_prio_enabled(ddev->sata_dev.ap, sdev, &enabled); > > > + if (rc) > > > + return rc; > > > + > > > + return sysfs_emit(buf, "%d\n", enabled); > > > +} > > > + > > > +static ssize_t sas_ncq_prio_enable_store(struct device *device, > > > + struct device_attribute *attr, > > > + const char *buf, size_t len) > > > +{ > > > + struct scsi_device *sdev = to_scsi_device(device); > > > + struct domain_device *ddev = sdev_to_domain_dev(sdev); > > > + bool enable; > > > + int rc; > > > + > > > + /* This attribute shall be visible for SATA devices only */ > > > + if (WARN_ON_ONCE(!dev_is_sata(ddev))) > > > + return -EINVAL; > > > + > > > + rc = kstrtobool(buf, &enable); > > > + if (rc) > > > + return rc; > > > + > > > + rc = ata_ncq_prio_enable(ddev->sata_dev.ap, sdev, enable); > > > + if (rc) > > > + return rc; > > > + > > > + return len; > > > +} > > > + > > > +DEVICE_ATTR(ncq_prio_enable, S_IRUGO | S_IWUSR, > > > + sas_ncq_prio_enable_show, sas_ncq_prio_enable_store); > > > + > > > +static struct attribute *sas_ata_sdev_attrs[] = { > > > + &dev_attr_ncq_prio_supported.attr, > > > + &dev_attr_ncq_prio_enable.attr, > > > + NULL > > > +}; > > > + > > > +static umode_t sas_ata_attr_is_visible(struct kobject *kobj, > > > + struct attribute *attr, int i) > > > +{ > > > + struct device *dev = kobj_to_dev(kobj); > > > + struct scsi_device *sdev = to_scsi_device(dev); > > > + struct domain_device *ddev = sdev_to_domain_dev(sdev); > > > + > > > + if (!dev_is_sata(ddev)) > > > + return 0; > > > + > > > + return attr->mode; > > > +} > > > + > > > +const struct attribute_group sas_ata_sdev_attr_group = { > > > + .attrs = sas_ata_sdev_attrs, > > > + .is_visible = sas_ata_attr_is_visible, > > > +}; > > > +EXPORT_SYMBOL_GPL(sas_ata_sdev_attr_group); > > > diff --git a/include/scsi/sas_ata.h b/include/scsi/sas_ata.h > > > index 2f8c719840a6..92e27e7bf088 100644 > > > --- a/include/scsi/sas_ata.h > > > +++ b/include/scsi/sas_ata.h > > > @@ -39,6 +39,9 @@ int smp_ata_check_ready_type(struct ata_link *link); > > > int sas_discover_sata(struct domain_device *dev); > > > int sas_ata_add_dev(struct domain_device *parent, struct ex_phy *phy, > > > struct domain_device *child, int phy_id); > > > + > > > +extern const struct attribute_group sas_ata_sdev_attr_group; > > > + > > > #else > > > > > > static inline void sas_ata_disabled_notice(void) > > > @@ -123,6 +126,9 @@ static inline int sas_ata_add_dev(struct domain_device *parent, struct ex_phy *p > > > sas_ata_disabled_notice(); > > > return -ENODEV; > > > } > > > + > > > +#define sas_ata_sdev_attr_group ((struct attribute_group) {}) > > > + > > > #endif > > > > > > #endif /* _SAS_ATA_H_ */ > > > -- > > > 2.44.0.278.ge034bb2e1d-goog > > >