From: Theodore Ts'o Subject: [PATCH 14/42] ext4: truncate block allocated on a failed ext4_write_begin Date: Thu, 9 Oct 2008 00:05:32 -0400 Message-ID: <1223525160-9887-15-git-send-email-tytso@mit.edu> References: <1223525160-9887-1-git-send-email-tytso@mit.edu> <1223525160-9887-2-git-send-email-tytso@mit.edu> <1223525160-9887-3-git-send-email-tytso@mit.edu> <1223525160-9887-4-git-send-email-tytso@mit.edu> <1223525160-9887-5-git-send-email-tytso@mit.edu> <1223525160-9887-6-git-send-email-tytso@mit.edu> <1223525160-9887-7-git-send-email-tytso@mit.edu> <1223525160-9887-8-git-send-email-tytso@mit.edu> <1223525160-9887-9-git-send-email-tytso@mit.edu> <1223525160-9887-10-git-send-email-tytso@mit.edu> <1223525160-9887-11-git-send-email-tytso@mit.edu> <1223525160-9887-12-git-send-email-tytso@mit.edu> <1223525160-9887-13-git-send-email-tytso@mit.edu> <1223525160-9887-14-git-send-email-tytso@mit.edu> Cc: "Aneesh Kumar K.V" , "Theodore Ts'o" To: linux-ext4@vger.kernel.org, linux-kernel@vger.kernel.org Return-path: Received: from www.church-of-our-saviour.org ([69.25.196.31]:54505 "EHLO thunker.thunk.org" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1757597AbYJIEGN (ORCPT ); Thu, 9 Oct 2008 00:06:13 -0400 In-Reply-To: <1223525160-9887-14-git-send-email-tytso@mit.edu> Sender: linux-ext4-owner@vger.kernel.org List-ID: From: Aneesh Kumar K.V For blocksize < pagesize we need to remove blocks that got allocated in block_write_begin() if we fail with ENOSPC for later blocks. block_write_begin() internally does this if it allocated pages locally. This makes sure we don't have blocks outside inode.i_size during ENOSPC. Signed-off-by: Aneesh Kumar K.V Signed-off-by: "Theodore Ts'o" --- fs/ext4/inode.c | 14 ++++++++++++++ 1 files changed, 14 insertions(+), 0 deletions(-) diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c index f97b347..634f0bc 100644 --- a/fs/ext4/inode.c +++ b/fs/ext4/inode.c @@ -1391,6 +1391,13 @@ retry: unlock_page(page); ext4_journal_stop(handle); page_cache_release(page); + /* + * block_write_begin may have instantiated a few blocks + * outside i_size. Trim these off again. Don't need + * i_size_read because we hold i_mutex. + */ + if (pos + len > inode->i_size) + vmtruncate(inode, inode->i_size); } if (ret == -ENOSPC && ext4_should_retry_alloc(inode->i_sb, &retries)) @@ -2560,6 +2567,13 @@ retry: unlock_page(page); ext4_journal_stop(handle); page_cache_release(page); + /* + * block_write_begin may have instantiated a few blocks + * outside i_size. Trim these off again. Don't need + * i_size_read because we hold i_mutex. + */ + if (pos + len > inode->i_size) + vmtruncate(inode, inode->i_size); } if (ret == -ENOSPC && ext4_should_retry_alloc(inode->i_sb, &retries)) -- 1.5.6.1.205.ge2c7.dirty