From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Message-ID: <1493782395.23202.84.camel@haakon3.risingtidesystems.com> Subject: Re: [PATCH 25/27] block: remove the discard_zeroes_data flag From: "Nicholas A. Bellinger" To: "hch@lst.de" Cc: Bart Van Assche , "agk@redhat.com" , "lars.ellenberg@linbit.com" , "snitzer@redhat.com" , "martin.petersen@oracle.com" , "philipp.reisner@linbit.com" , "axboe@kernel.dk" , "shli@kernel.org" , "linux-scsi@vger.kernel.org" , "dm-devel@redhat.com" , "drbd-dev@lists.linbit.com" , "linux-block@vger.kernel.org" , "target-devel@vger.kernel.org" , "linux-raid@vger.kernel.org" Date: Tue, 02 May 2017 20:33:15 -0700 In-Reply-To: <20170502072328.GA11522@lst.de> References: <20170405172125.22600-1-hch@lst.de> <20170405172125.22600-26-hch@lst.de> <1493671519.2665.15.camel@sandisk.com> <1493707425.23202.77.camel@haakon3.risingtidesystems.com> <1493709373.23202.79.camel@haakon3.risingtidesystems.com> <20170502072328.GA11522@lst.de> Content-Type: text/plain; charset="UTF-8" Mime-Version: 1.0 List-ID: On Tue, 2017-05-02 at 09:23 +0200, hch@lst.de wrote: > On Tue, May 02, 2017 at 12:16:13AM -0700, Nicholas A. Bellinger wrote: > > Or, another options is use bdev_write_zeroes_sectors() to determine when > > dev_attrib->unmap_zeroes_data should be set. > > Yes, that in combination with your patch to use bdev_write_zeroes_sectors > for zeroing from write same seems like the right fix. The larger target/iblock conversion patch looks like post v4.12 material at this point, so to avoid breakage wrt to existing LBPRZ behavior, I'll plan to push the following patch post -rc1. diff --git a/drivers/target/target_core_device.c b/drivers/target/target_core_device.c index d2f089c..e7caf78 100644 --- a/drivers/target/target_core_device.c +++ b/drivers/target/target_core_device.c @@ -851,7 +851,7 @@ bool target_configure_unmap_from_queue(struct se_dev_attrib *attrib, attrib->unmap_granularity = q->limits.discard_granularity / block_size; attrib->unmap_granularity_alignment = q->limits.discard_alignment / block_size; - attrib->unmap_zeroes_data = 0; + attrib->unmap_zeroes_data = (q->limits.max_write_zeroes_sectors); return true; } EXPORT_SYMBOL(target_configure_unmap_from_queue);