From: Theodore Ts'o Subject: [PATCH 2.6.33.y 37/40] ext4: restart ext4_ext_remove_space() after transaction restart Date: Tue, 1 Jun 2010 08:03:24 -0400 Message-ID: <1275393807-14369-37-git-send-email-tytso@mit.edu> References: <1275393807-14369-1-git-send-email-tytso@mit.edu> Cc: Ext4 Developers List , Dmitry Monakhov , "Theodore Ts'o" To: stable@vger.kernel.org Return-path: Received: from THUNK.ORG ([69.25.196.29]:47271 "EHLO thunker.thunk.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756061Ab0FAMDd (ORCPT ); Tue, 1 Jun 2010 08:03:33 -0400 In-Reply-To: <1275393807-14369-1-git-send-email-tytso@mit.edu> Sender: linux-ext4-owner@vger.kernel.org List-ID: From: Dmitry Monakhov commit 0617b83fa239db9743a18ce6cc0e556f4d0fd567 upstream (as of v2.6.34-git13) If i_data_sem was internally dropped due to transaction restart, it is necessary to restart path look-up because extents tree was possibly modified by ext4_get_block(). https://bugzilla.kernel.org/show_bug.cgi?id=15827 Signed-off-by: Dmitry Monakhov Signed-off-by: "Theodore Ts'o" Acked-by: Jan Kara --- fs/ext4/extents.c | 16 +++++++++------- 1 files changed, 9 insertions(+), 7 deletions(-) diff --git a/fs/ext4/extents.c b/fs/ext4/extents.c index 799416f..1fca430 100644 --- a/fs/ext4/extents.c +++ b/fs/ext4/extents.c @@ -107,11 +107,8 @@ static int ext4_ext_truncate_extend_restart(handle_t *handle, if (err <= 0) return err; err = ext4_truncate_restart_trans(handle, inode, needed); - /* - * We have dropped i_data_sem so someone might have cached again - * an extent we are going to truncate. - */ - ext4_ext_invalidate_cache(inode); + if (err == 0) + err = -EAGAIN; return err; } @@ -2257,7 +2254,7 @@ static int ext4_ext_remove_space(struct inode *inode, ext4_lblk_t start) int depth = ext_depth(inode); struct ext4_ext_path *path; handle_t *handle; - int i = 0, err = 0; + int i, err; ext_debug("truncate since %u\n", start); @@ -2266,23 +2263,26 @@ static int ext4_ext_remove_space(struct inode *inode, ext4_lblk_t start) if (IS_ERR(handle)) return PTR_ERR(handle); +again: ext4_ext_invalidate_cache(inode); /* * We start scanning from right side, freeing all the blocks * after i_size and walking into the tree depth-wise. */ + depth = ext_depth(inode); path = kzalloc(sizeof(struct ext4_ext_path) * (depth + 1), GFP_NOFS); if (path == NULL) { ext4_journal_stop(handle); return -ENOMEM; } + path[0].p_depth = depth; path[0].p_hdr = ext_inode_hdr(inode); if (ext4_ext_check(inode, path[0].p_hdr, depth)) { err = -EIO; goto out; } - path[0].p_depth = depth; + i = err = 0; while (i >= 0 && err == 0) { if (i == depth) { @@ -2376,6 +2376,8 @@ static int ext4_ext_remove_space(struct inode *inode, ext4_lblk_t start) out: ext4_ext_drop_refs(path); kfree(path); + if (err == -EAGAIN) + goto again; ext4_journal_stop(handle); return err; -- 1.6.6.1.1.g974db.dirty