From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) (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 481341F94D for ; Tue, 8 Oct 2024 02:48:18 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=170.10.129.124 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1728355701; cv=none; b=heeIRLW2tMiAcvcDeA7w5ulEtOLZFrGXWeAwbZuE1rt4RFIQSscSX8R8Nx7SEqDb9BfBPG1v0gLurW12S1a2kUz0qZckBiYCNQ95lZm8ky0m5DfIQ65LxGoEAQ8sp0lWxp/uPpD0W/5uwMQxk/qkxStLTXPZkC9jQjGWXcWUm9I= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1728355701; c=relaxed/simple; bh=00l3ew/+mUdwOjmX4YW9hrWtqAXJr9UModlO93k7rBo=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=T0dqxrOjAbzejApib3d+LXNI/PwhMLm4TXSPVYc2K+BAbvYGSlwbmsniD8xCVZJGPnUKvu+Zg/76CkmWbc6DXA9DAF54YmaVPpvEpg9xJuIYYBLJqXzSftIh6CsvmECKxkMU9jU7YFl2XYmevzXG9uyTsbdgIxGEImic8BvmfNg= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=redhat.com; spf=pass smtp.mailfrom=redhat.com; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b=SqWeD9gK; arc=none smtp.client-ip=170.10.129.124 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=redhat.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=redhat.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="SqWeD9gK" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1728355698; 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: in-reply-to:in-reply-to:references:references; bh=72e4QnH4D6K+NkUJS7yS03i2OR/C2I3oUkzItklfg0k=; b=SqWeD9gKBAR8euuF/GdrG1EQ+7WI1z1YhMBTGh+kRhq5Lig9R3OKNTYT4UyKdx9Vnuyet+ lDDixCg6LvOKnZ5Uvoi9FxEZWwdnXobezW47r91D++jPD8aLKJn8MPXoS745ICfosTDV/E MyW1lXGmtsgaF9xnw6XIylcZEpyhN2k= Received: from mx-prod-mc-01.mail-002.prod.us-west-2.aws.redhat.com (ec2-54-186-198-63.us-west-2.compute.amazonaws.com [54.186.198.63]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-245-Pb3mLiR8M_qUIZ8bAPL7CA-1; Mon, 07 Oct 2024 22:48:14 -0400 X-MC-Unique: Pb3mLiR8M_qUIZ8bAPL7CA-1 Received: from mx-prod-int-01.mail-002.prod.us-west-2.aws.redhat.com (mx-prod-int-01.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.4]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mx-prod-mc-01.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id 8624A19560B2; Tue, 8 Oct 2024 02:48:13 +0000 (UTC) Received: from fedora (unknown [10.72.116.102]) by mx-prod-int-01.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id B2F74300018D; Tue, 8 Oct 2024 02:48:08 +0000 (UTC) Date: Tue, 8 Oct 2024 10:48:02 +0800 From: Ming Lei To: Uday Shankar Cc: Jens Axboe , Jonathan Corbet , linux-block@vger.kernel.org, linux-doc@vger.kernel.org Subject: Re: [PATCH v4 4/5] ublk: support device recovery without I/O queueing Message-ID: References: <20241007182419.3263186-1-ushankar@purestorage.com> <20241007182419.3263186-5-ushankar@purestorage.com> Precedence: bulk X-Mailing-List: linux-doc@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: <20241007182419.3263186-5-ushankar@purestorage.com> X-Scanned-By: MIMEDefang 3.4.1 on 10.30.177.4 On Mon, Oct 07, 2024 at 12:24:17PM -0600, Uday Shankar wrote: > ublk currently supports the following behaviors on ublk server exit: > > A: outstanding I/Os get errors, subsequently issued I/Os get errors > B: outstanding I/Os get errors, subsequently issued I/Os queue > C: outstanding I/Os get reissued, subsequently issued I/Os queue > > and the following behaviors for recovery of preexisting block devices by > a future incarnation of the ublk server: > > 1: ublk devices stopped on ublk server exit (no recovery possible) > 2: ublk devices are recoverable using start/end_recovery commands > > The userspace interface allows selection of combinations of these > behaviors using flags specified at device creation time, namely: > > default behavior: A + 1 > UBLK_F_USER_RECOVERY: B + 2 > UBLK_F_USER_RECOVERY|UBLK_F_USER_RECOVERY_REISSUE: C + 2 > > The behavior A + 2 is currently unsupported. Add support for this > behavior under the new flag combination > UBLK_F_USER_RECOVERY|UBLK_F_USER_RECOVERY_FAIL_IO. > > Signed-off-by: Uday Shankar Reviewed-by: Ming Lei Thanks, Ming