Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752598Ab3GXOGo (ORCPT ); Wed, 24 Jul 2013 10:06:44 -0400 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:45849 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752273Ab3GXOGg (ORCPT ); Wed, 24 Jul 2013 10:06:36 -0400 Content-Type: text/plain; charset="UTF-8" Content-Disposition: inline Content-Transfer-Encoding: 8bit MIME-Version: 1.0 From: Ben Hutchings To: linux-kernel@vger.kernel.org, stable@vger.kernel.org CC: akpm@linux-foundation.org, "Linus Torvalds" , "Paul Clements" , "Rob Landley" Date: Wed, 24 Jul 2013 15:02:45 +0100 Message-ID: X-Mailer: LinuxStableQueue (scripts by bwh) Subject: [70/85] nbd: correct disconnect behavior In-Reply-To: X-SA-Exim-Connect-IP: 192.168.4.101 X-SA-Exim-Mail-From: ben@decadent.org.uk X-SA-Exim-Scanned: No (on shadbolt.decadent.org.uk); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2589 Lines: 78 3.2.49-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Paul Clements commit c378f70adbc1bbecd9e6db145019f14b2f688c7c upstream. Currently, when a disconnect is requested by the user (via NBD_DISCONNECT ioctl) the return from NBD_DO_IT is undefined (it is usually one of several error codes). This means that nbd-client does not know if a manual disconnect was performed or whether a network error occurred. Because of this, nbd-client's persist mode (which tries to reconnect after error, but not after manual disconnect) does not always work correctly. This change fixes this by causing NBD_DO_IT to always return 0 if a user requests a disconnect. This means that nbd-client can correctly either persist the connection (if an error occurred) or disconnect (if the user requested it). Signed-off-by: Paul Clements Acked-by: Rob Landley Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds [bwh: Backported to 3.2: adjust device pointer name] Signed-off-by: Ben Hutchings --- drivers/block/nbd.c | 7 ++++++- include/linux/nbd.h | 1 + 2 files changed, 7 insertions(+), 1 deletion(-) --- a/drivers/block/nbd.c +++ b/drivers/block/nbd.c @@ -598,8 +598,10 @@ static int __nbd_ioctl(struct block_devi if (!lo->sock) return -EINVAL; + lo->disconnect = 1; + nbd_send_req(lo, &sreq); - return 0; + return 0; } case NBD_CLEAR_SOCK: { @@ -629,6 +631,7 @@ static int __nbd_ioctl(struct block_devi lo->sock = SOCKET_I(inode); if (max_part > 0) bdev->bd_invalidated = 1; + lo->disconnect = 0; /* we're connected now */ return 0; } else { fput(file); @@ -701,6 +704,8 @@ static int __nbd_ioctl(struct block_devi set_capacity(lo->disk, 0); if (max_part > 0) ioctl_by_bdev(bdev, BLKRRPART, 0); + if (lo->disconnect) /* user requested, ignore socket errors */ + return 0; return lo->harderror; } --- a/include/linux/nbd.h +++ b/include/linux/nbd.h @@ -68,6 +68,7 @@ struct nbd_device { u64 bytesize; pid_t pid; /* pid of nbd-client, if attached */ int xmit_timeout; + int disconnect; /* a disconnect has been requested by user */ }; #endif -- 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/