Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755453AbbFOKAR (ORCPT ); Mon, 15 Jun 2015 06:00:17 -0400 Received: from cantor2.suse.de ([195.135.220.15]:37155 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756051AbbFOJ6n (ORCPT ); Mon, 15 Jun 2015 05:58:43 -0400 Date: Mon, 15 Jun 2015 11:58:40 +0200 From: Johannes Thumshirn To: Sreekanth Reddy Cc: jejb@kernel.org, hch@infradead.org, martin.petersen@oracle.com, linux-scsi@vger.kernel.org, JBottomley@Parallels.com, Sathya.Prakash@avagotech.com, linux-kernel@vger.kernel.org Subject: Re: [PATCH 19/20] [SCSI] mpt3sas: When device is blocked followed by unblock fails, unfreeze the I/Os Message-ID: <20150615095840.GK5660@c203.arch.suse.de> References: <1434102153-38581-1-git-send-email-Sreekanth.Reddy@avagotech.com> <1434102153-38581-20-git-send-email-Sreekanth.Reddy@avagotech.com> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <1434102153-38581-20-git-send-email-Sreekanth.Reddy@avagotech.com> User-Agent: Mutt/1.5.23 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 6374 Lines: 170 On Fri, Jun 12, 2015 at 03:12:31PM +0530, Sreekanth Reddy wrote: > Issue: When the disks are getting discovered and assigned device > handles by the kernel, a device block followed by an unblock > (due to broadcast primitives) issued by the driver is > interspersed by the kernel changing the state of the device. > Therefore the unblock by the driver results in a no operation > within the kernel API. > > To fix this one, the below patch checks the return of the unblock API > and performs a block followed by an unblock to unfreeze the block > layer's I/O queue. Sufficient checks and prints are also added in the > driver to identify this condition caused by the kernel. > > Signed-off-by: Sreekanth Reddy > --- > drivers/scsi/mpt3sas/mpt3sas_scsih.c | 89 ++++++++++++++++++++++++++++++------ > 1 file changed, 75 insertions(+), 14 deletions(-) > > diff --git a/drivers/scsi/mpt3sas/mpt3sas_scsih.c b/drivers/scsi/mpt3sas/mpt3sas_scsih.c > index 42bb731..5405a2f 100644 > --- a/drivers/scsi/mpt3sas/mpt3sas_scsih.c > +++ b/drivers/scsi/mpt3sas/mpt3sas_scsih.c > @@ -2605,6 +2605,75 @@ _scsih_fw_event_cleanup_queue(struct MPT3SAS_ADAPTER *ioc) > } > > /** > + * _scsih_internal_device_block - block the sdev device > + * @sdev: per device object > + * @sas_device_priv_data : per device driver private data > + * > + * make sure device is blocked without error, if not > + * print an error > + */ > +static void > +_scsih_internal_device_block(struct scsi_device *sdev, > + struct MPT3SAS_DEVICE *sas_device_priv_data) > +{ > + int r = 0; > + > + sdev_printk(KERN_INFO, sdev, "device_block, handle(0x%04x)\n", > + sas_device_priv_data->sas_target->handle); > + sas_device_priv_data->block = 1; > + > + r = scsi_internal_device_block(sdev); > + if (r == -EINVAL) > + sdev_printk(KERN_WARNING, sdev, > + "device_block failed with return(%d) for handle(0x%04x)\n", > + sas_device_priv_data->sas_target->handle, r); > +} > + > +/** > + * _scsih_internal_device_unblock - unblock the sdev device > + * @sdev: per device object > + * @sas_device_priv_data : per device driver private data > + * make sure device is unblocked without error, if not retry > + * by blocking and then unblocking > + */ > + > +static void > +_scsih_internal_device_unblock(struct scsi_device *sdev, > + struct MPT3SAS_DEVICE *sas_device_priv_data) > +{ > + int r = 0; > + > + sdev_printk(KERN_WARNING, sdev, "device_unblock and setting to running, " > + "handle(0x%04x)\n", sas_device_priv_data->sas_target->handle); > + sas_device_priv_data->block = 0; > + r = scsi_internal_device_unblock(sdev, SDEV_RUNNING); > + if (r == -EINVAL) { > + /* The device has been set to SDEV_RUNNING by SD layer during > + * device addition but the request queue is still stopped by > + * our earlier block call. We need to perform a block again > + * to get the device to SDEV_BLOCK and then to SDEV_RUNNING */ > + > + sdev_printk(KERN_WARNING, sdev, > + "device_unblock failed with return(%d) for handle(0x%04x) " > + "performing a block followed by an unblock\n", > + sas_device_priv_data->sas_target->handle, r); > + sas_device_priv_data->block = 1; > + r = scsi_internal_device_block(sdev); > + if (r) > + sdev_printk(KERN_WARNING, sdev, "retried device_block " > + "failed with return(%d) for handle(0x%04x)\n", > + sas_device_priv_data->sas_target->handle, r); > + > + sas_device_priv_data->block = 0; > + r = scsi_internal_device_unblock(sdev, SDEV_RUNNING); > + if (r) > + sdev_printk(KERN_WARNING, sdev, "retried device_unblock" > + " failed with return(%d) for handle(0x%04x)\n", > + sas_device_priv_data->sas_target->handle, r); > + } > +} > + > +/** > * _scsih_ublock_io_all_device - unblock every device > * @ioc: per adapter object > * > @@ -2623,11 +2692,10 @@ _scsih_ublock_io_all_device(struct MPT3SAS_ADAPTER *ioc) > if (!sas_device_priv_data->block) > continue; > > - sas_device_priv_data->block = 0; > dewtprintk(ioc, sdev_printk(KERN_INFO, sdev, > "device_running, handle(0x%04x)\n", > sas_device_priv_data->sas_target->handle)); > - scsi_internal_device_unblock(sdev, SDEV_RUNNING); > + _scsih_internal_device_unblock(sdev, sas_device_priv_data); > } > } > > @@ -2652,10 +2720,9 @@ _scsih_ublock_io_device(struct MPT3SAS_ADAPTER *ioc, u64 sas_address) > if (sas_device_priv_data->sas_target->sas_address > != sas_address) > continue; > - if (sas_device_priv_data->block) { > - sas_device_priv_data->block = 0; > - scsi_internal_device_unblock(sdev, SDEV_RUNNING); > - } > + if (sas_device_priv_data->block) > + _scsih_internal_device_unblock(sdev, > + sas_device_priv_data); > } > } > > @@ -2678,10 +2745,7 @@ _scsih_block_io_all_device(struct MPT3SAS_ADAPTER *ioc) > continue; > if (sas_device_priv_data->block) > continue; > - sas_device_priv_data->block = 1; > - scsi_internal_device_block(sdev); > - sdev_printk(KERN_INFO, sdev, "device_blocked, handle(0x%04x)\n", > - sas_device_priv_data->sas_target->handle); > + _scsih_internal_device_block(sdev, sas_device_priv_data); > } > } > > @@ -2713,10 +2777,7 @@ _scsih_block_io_device(struct MPT3SAS_ADAPTER *ioc, u16 handle) > continue; > if (sas_device->pend_sas_rphy_add) > continue; > - sas_device_priv_data->block = 1; > - scsi_internal_device_block(sdev); > - sdev_printk(KERN_INFO, sdev, > - "device_blocked, handle(0x%04x)\n", handle); > + _scsih_internal_device_block(sdev, sas_device_priv_data); > } > } > > -- > 2.0.2 > > -- > To unsubscribe from this list: send the line "unsubscribe linux-scsi" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html Reviewed-by: Johannes Thumshirn -- Johannes Thumshirn Storage jthumshirn@suse.de +49 911 74053 689 SUSE LINUX GmbH, Maxfeldstr. 5, 90409 N?rnberg GF: F. Imend?rffer, J. Smithard, J. Guild, D. Upmanyu, G. Norton HRB 21284 (AG N?rnberg) -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/