From patchwork Mon Oct 22 16:51:34 2012 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Alex Elder X-Patchwork-Id: 1627081 Return-Path: X-Original-To: patchwork-ceph-devel@patchwork.kernel.org Delivered-To: patchwork-process-083081@patchwork1.kernel.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by patchwork1.kernel.org (Postfix) with ESMTP id AC16A4020E for ; Mon, 22 Oct 2012 16:51:38 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755344Ab2JVQvi (ORCPT ); Mon, 22 Oct 2012 12:51:38 -0400 Received: from mail-ie0-f174.google.com ([209.85.223.174]:40328 "EHLO mail-ie0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755015Ab2JVQvh (ORCPT ); Mon, 22 Oct 2012 12:51:37 -0400 Received: by mail-ie0-f174.google.com with SMTP id k13so3910449iea.19 for ; Mon, 22 Oct 2012 09:51:37 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20120113; h=message-id:date:from:user-agent:mime-version:to:subject:references :in-reply-to:content-type:content-transfer-encoding :x-gm-message-state; bh=yn2rnrUL7zvFwHVj6ChJXsYSX3G9W4Tc353OblW/SHI=; b=Jr3Cpcb6tXLt2FiA83KlOLujbvj9U6OZK+hMT38/EXlCY43/tnGv2jt5bX/a6VE2nz N09aSj+cFOTGnTQDz976BuGqYZmsxhcRK2CZxDoVWyT+VVmvbwtkBaPkuBwuFP74rnV7 q47pLlHvJlnTo139VDe1edLar+AQAECrtsNbuO3sfMfTDXEuyMISLX+/eCiETAWMM+UW c6WmA2CcNhbSGe71QP4kTgeaHMljZXyaJuHpXmM6XEidHqryHIszOAGALYqOno+ZkXiU nuiAgFT5126esnbYgz8AERXKQCKUyId7Ouk5VKVMlpl/4dmmYwK6xyVZsmdKSLpGnLqy pFrw== Received: by 10.50.217.225 with SMTP id pb1mr10013194igc.46.1350924697460; Mon, 22 Oct 2012 09:51:37 -0700 (PDT) Received: from [172.22.22.4] (c-71-195-31-37.hsd1.mn.comcast.net. [71.195.31.37]) by mx.google.com with ESMTPS id uj6sm9012582igb.4.2012.10.22.09.51.34 (version=SSLv3 cipher=OTHER); Mon, 22 Oct 2012 09:51:36 -0700 (PDT) Message-ID: <50857996.70502@inktank.com> Date: Mon, 22 Oct 2012 11:51:34 -0500 From: Alex Elder User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:16.0) Gecko/20121011 Thunderbird/16.0.1 MIME-Version: 1.0 To: ceph-devel@vger.kernel.org Subject: [PATCH 2/4] rbd: increase maximum snapshot name length References: <5085791C.9010205@inktank.com> In-Reply-To: <5085791C.9010205@inktank.com> X-Gm-Message-State: ALoCoQk98whj+cD5qf0XdzH3POMZnqhQ3WmmqYzEHfEZugq8X7O3U5mHJxStvMw2YEOAjcYA8KR7 Sender: ceph-devel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: ceph-devel@vger.kernel.org Change RBD_MAX_SNAP_NAME_LEN to be based on NAME_MAX. That is a practical limit for the length of a snapshot name (based on the presence of a directory using the name under /sys/bus/rbd to represent the snapshot). The /sys entry is created by prefixing it with "snap_"; define that prefix symbolically, and take its length into account in defining the snapshot name length limit. Enforce the limit in rbd_add_parse_args(). Also delete a dout() call in that function that was not meant to be committed. Signed-off-by: Alex Elder Reviewed-by: Josh Durgin Reviewed-by: Dan Mick --- drivers/block/rbd.c | 16 +++++++++++----- 1 file changed, 11 insertions(+), 5 deletions(-) ret = device_register(dev); @@ -2797,8 +2800,13 @@ static char *rbd_add_parse_args(struct rbd_device *rbd_dev, if (!rbd_dev->image_name) goto out_err; - /* Snapshot name is optional */ + /* Snapshot name is optional; default is to use "head" */ + len = next_token(&buf); + if (len > RBD_MAX_SNAP_NAME_LEN) { + err_ptr = ERR_PTR(-ENAMETOOLONG); + goto out_err; + } if (!len) { buf = RBD_SNAP_HEAD_NAME; /* No snapshot supplied */ len = sizeof (RBD_SNAP_HEAD_NAME) - 1; @@ -2809,8 +2817,6 @@ static char *rbd_add_parse_args(struct rbd_device *rbd_dev, memcpy(snap_name, buf, len); *(snap_name + len) = '\0'; -dout(" SNAP_NAME is <%s>, len is %zd\n", snap_name, len); - return snap_name; out_err: diff --git a/drivers/block/rbd.c b/drivers/block/rbd.c index 4734446..4858d92 100644 --- a/drivers/block/rbd.c +++ b/drivers/block/rbd.c @@ -61,7 +61,10 @@ #define RBD_MINORS_PER_MAJOR 256 /* max minors per blkdev */ -#define RBD_MAX_SNAP_NAME_LEN 32 +#define RBD_SNAP_DEV_NAME_PREFIX "snap_" +#define RBD_MAX_SNAP_NAME_LEN \ + (NAME_MAX - (sizeof (RBD_SNAP_DEV_NAME_PREFIX) - 1)) + #define RBD_MAX_SNAP_COUNT 510 /* allows max snapc to fit in 4KB */ #define RBD_MAX_OPT_LEN 1024 @@ -2063,7 +2066,7 @@ static int rbd_register_snap_dev(struct rbd_snap *snap, dev->type = &rbd_snap_device_type; dev->parent = parent; dev->release = rbd_snap_dev_release; - dev_set_name(dev, "snap_%s", snap->name); + dev_set_name(dev, "%s%s", RBD_SNAP_DEV_NAME_PREFIX, snap->name); dout("%s: registering device for snapshot %s\n", __func__, snap->name);