From patchwork Tue Jun 7 15:07:39 2011 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Amir G." X-Patchwork-Id: 99234 X-Patchwork-Delegate: tytso@mit.edu Return-Path: X-Original-To: patchwork-incoming@ozlabs.org Delivered-To: patchwork-incoming@ozlabs.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id E5864B6F91 for ; Wed, 8 Jun 2011 01:09:29 +1000 (EST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756559Ab1FGPJ2 (ORCPT ); Tue, 7 Jun 2011 11:09:28 -0400 Received: from mail-wy0-f174.google.com ([74.125.82.174]:60303 "EHLO mail-wy0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755431Ab1FGPJ1 (ORCPT ); Tue, 7 Jun 2011 11:09:27 -0400 Received: by mail-wy0-f174.google.com with SMTP id 21so3629480wya.19 for ; Tue, 07 Jun 2011 08:09:27 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:sender:from:to:cc:subject:date:message-id :x-mailer:in-reply-to:references; bh=Zt02/phFEnvAaXxxL0fCc5/2aGGBN/EWb7st4BU8Imk=; b=toTadTlG4NAfnFMGVtqlqgQZlnfQnhf9YgqASmR++AlAJPgGtCdCKG25sboD/eCbu5 hb8ybWMUMDU2U1wO0IgStoX4KrlLFjdaeAl6F37oZUvkBam5cTed1HlHHbQpQaghYRHH wzTLYJQ+1bfrtHmv/oC6qC9XKRcgjliUYRsPw= DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=sender:from:to:cc:subject:date:message-id:x-mailer:in-reply-to :references; b=Sc96tLH5ciyW+bUm5bbsGG9hYb+n2+fVu6ICIKnfhKxo446T5P5ZO88EwcaXDNdmWw 6pC6vvXgxI7k7j3o3vGyUdMX3jUjvIBXT4Y6kNBhKGdyjhVS0veJ/ySlOcPf3tpZ1vzz sWY5UYwdcX+zlmysCQcfIxOL054v+rvEmV0/g= Received: by 10.227.208.65 with SMTP id gb1mr6487698wbb.42.1307459367319; Tue, 07 Jun 2011 08:09:27 -0700 (PDT) Received: from localhost.localdomain (bzq-218-153-66.cablep.bezeqint.net [81.218.153.66]) by mx.google.com with ESMTPS id en1sm3622645wbb.52.2011.06.07.08.09.25 (version=TLSv1/SSLv3 cipher=OTHER); Tue, 07 Jun 2011 08:09:26 -0700 (PDT) From: amir73il@users.sourceforge.net To: linux-ext4@vger.kernel.org Cc: tytso@mit.edu, lczerner@redhat.com, Amir Goldstein , Yongqiang Yang Subject: [PATCH v1 12/36] ext4: snapshot file - store on disk Date: Tue, 7 Jun 2011 18:07:39 +0300 Message-Id: <1307459283-22130-13-git-send-email-amir73il@users.sourceforge.net> X-Mailer: git-send-email 1.7.4.1 In-Reply-To: <1307459283-22130-1-git-send-email-amir73il@users.sourceforge.net> References: <1307459283-22130-1-git-send-email-amir73il@users.sourceforge.net> Sender: linux-ext4-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-ext4@vger.kernel.org From: Amir Goldstein Snapshot inode is stored differently in memory and on disk. During store and load of snapshot inode, some of the inode flags and fields are converted. Signed-off-by: Amir Goldstein Signed-off-by: Yongqiang Yang --- fs/ext4/inode.c | 33 +++++++++++++++++++++++++++------ 1 files changed, 27 insertions(+), 6 deletions(-) diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c index b210b33..33692fd 100644 --- a/fs/ext4/inode.c +++ b/fs/ext4/inode.c @@ -5183,6 +5183,17 @@ struct inode *ext4_iget(struct super_block *sb, unsigned long ino) */ for (block = 0; block < EXT4_N_BLOCKS; block++) ei->i_data[block] = raw_inode->i_block[block]; + /* snapshot on-disk list is stored in snapshot inode on-disk version */ + if (ext4_snapshot_file(inode)) { + ei->i_next_snapshot_ino = + le32_to_cpu(raw_inode->i_disk_version); + /* + * snapshot volume size is stored in i_disksize. + * in-memory i_size of snapshot files is set to 0 (disabled). + * enabling a snapshot is setting i_size to i_disksize. + */ + inode->i_size = 0; + } INIT_LIST_HEAD(&ei->i_orphan); /* @@ -5447,12 +5458,22 @@ static int ext4_do_update_inode(handle_t *handle, for (block = 0; block < EXT4_N_BLOCKS; block++) raw_inode->i_block[block] = ei->i_data[block]; - raw_inode->i_disk_version = cpu_to_le32(inode->i_version); - if (ei->i_extra_isize) { - if (EXT4_FITS_IN_INODE(raw_inode, ei, i_version_hi)) - raw_inode->i_version_hi = - cpu_to_le32(inode->i_version >> 32); - raw_inode->i_extra_isize = cpu_to_le16(ei->i_extra_isize); + if (ext4_snapshot_file(inode)) { + /* + * Snapshot on-disk list overrides snapshot on-disk version. + * Snapshot files are not writable and have a fixed version. + */ + raw_inode->i_disk_version = + cpu_to_le32(ei->i_next_snapshot_ino); + } else { + raw_inode->i_disk_version = cpu_to_le32(inode->i_version); + if (ei->i_extra_isize) { + if (EXT4_FITS_IN_INODE(raw_inode, ei, i_version_hi)) + raw_inode->i_version_hi = + cpu_to_le32(inode->i_version >> 32); + raw_inode->i_extra_isize = + cpu_to_le16(ei->i_extra_isize); + } } BUFFER_TRACE(bh, "call ext4_handle_dirty_metadata");