From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from out-187.mta1.migadu.com (out-187.mta1.migadu.com [95.215.58.187]) (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 D64485B21A for ; Sun, 26 Apr 2026 06:28:52 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=95.215.58.187 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1777184934; cv=none; b=cLGTofV6++oC5SP48md6bgG+ZaYkYRFj7zC3bkc7LI6d0okI8ZSQRem5ZRelz1DXhW33SVDtF/WVJC18oc+ou3q0rNJGFMMhFTgiEe9cKLBmYcqcCnH9+hkfMa8rn+/MdpWH9OvlWsed/+sIzUSFnLHvKN3yQIkl0fI3Op05Rls= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1777184934; c=relaxed/simple; bh=GKc5fn8cAxo8vOQ+6BrowLOsE4kaG2euF9Gx/fTWt4E=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=t8KWw44HCoxUl68ngE4hzdCLjZtYReqgaXCREP3g4pcE4kcBN7hpOr7Oa+j7/CdgIIQ/ROIop02SpW4T1dt1cjAAt7GrCAF0r7SaXfkf/P7N6MlB5XvesJaYVmgyLGqOMAaEZ54Nhfo3AKAGz9meVH03yyiRoAW9t3A38QS24kQ= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev; spf=pass smtp.mailfrom=linux.dev; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b=oeKpelTn; arc=none smtp.client-ip=95.215.58.187 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.dev Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b="oeKpelTn" Message-ID: <4315ac3f-cf0b-484b-a925-0e539a1bfff2@linux.dev> DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1777184930; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=JecWUIgfgo7vZ7f5H1X7xSHgikkXOcpBTnzxsEo47VM=; b=oeKpelTn3SEdQjNofPzNjchTQ282h8U4yiWj96kKTabjaqhLGJO1yla4fwHjol7GfJhrjs 1DdV08Xq6QbhqhdTo0VAKLsO7wYZ0lM2VodBO1TJb/KlpwBvjOd8oN33HFCoUINhD+XVSj 4p73a/VbMHkjnUqcnOtXlyQi+jrkEto= Date: Sun, 26 Apr 2026 08:28:42 +0200 Precedence: bulk X-Mailing-List: linux-xfs@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Subject: Re: [PATCH v3 3/3] xfs: add a sysfs entry to enable write zeroes even if HW does not support it To: Christoph Hellwig , Pankaj Raghav Cc: linux-xfs@vger.kernel.org, bfoster@redhat.com, lukas@herbolt.com, "Darrick J . Wong" , dgc@kernel.org, gost.dev@samsung.com, andres@anarazel.de, kundan.kumar@samsung.com, cem@kernel.org References: <20260420105539.3644999-1-p.raghav@samsung.com> <20260420105539.3644999-4-p.raghav@samsung.com> Content-Language: en-US X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. From: Pankaj Raghav In-Reply-To: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-Migadu-Flow: FLOW_OUT On 4/24/26 15:52, Christoph Hellwig wrote: > On Mon, Apr 20, 2026 at 12:55:39PM +0200, Pankaj Raghav wrote: >> From: Lukas Herbolt >> >> Add a xfs sysfs entry that will not return ENOTSUPP for >> FALLOC_FL_WRITE_ZEROES flag in fallocate even if the hardware does not >> support deallocate on write zeroes. This is useful for testing this >> feature independent of the HW underneath. > > I don't think it is. We can easily test this using a loop or scsi_debug > device. And in fact should by adding an xfstests that uses such > synthetic devices. > This makes sense. Also this avoids adding hardware specific knobs in the filesystem. -- Pankaj