From patchwork Tue Apr 9 15:15:59 2013 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Subject: ext4: defragmentation code cleanup From: Dmitri Monakho X-Patchwork-Id: 235110 Message-Id: <1365520559-6622-1-git-send-email-dmonakhov@openvz.org> To: linux-ext4@vger.kernel.org Cc: Dmitry Monakhov Date: Tue, 9 Apr 2013 19:15:59 +0400 - grab_cache_page_write_begin() may not wait on page's writeback since (1d1d1a767206). But it is still reasonable to wait on page's writeback here in order to be on the safe side. - Fix miss typo: pass 'length' instead of 'end' to __block_write_begin() https://bugzilla.kernel.org/show_bug.cgi?id=56241 TESTCASE: git://oss.sgi.com/xfs/cmds/xfstests.git MKFS_OPTIONS="-b1024" ; ./check ext4/304 Signed-off-by: Dmitry Monakhov Reviewed-by: Akira Fujita --- fs/ext4/move_extent.c | 11 +++++++++-- 1 files changed, 9 insertions(+), 2 deletions(-) diff --git a/fs/ext4/move_extent.c b/fs/ext4/move_extent.c index 33e1c08..58b33e9 100644 --- a/fs/ext4/move_extent.c +++ b/fs/ext4/move_extent.c @@ -737,6 +737,7 @@ mext_replace_branches(handle_t *handle, struct inode *orig_inode, donor_off += dext_alen; orig_off += dext_alen; + BUG_ON(replaced_count > count); /* Already moved the expected blocks */ if (replaced_count >= count) break; @@ -814,7 +815,13 @@ mext_page_double_lock(struct inode *inode1, struct inode *inode2, page_cache_release(page[0]); return -ENOMEM; } - + /* + * grab_cache_page_write_begin() may not wait on page's writeback if + * BDI not demand that. But it is reasonable to be very conservative + * here and explicitly wait on page's writeback + */ + wait_on_page_writeback(page[0]); + wait_on_page_writeback(page[1]); if (inode1 > inode2) { struct page *tmp; tmp = page[0]; @@ -1033,7 +1040,7 @@ data_copy: } /* Perform all necessary steps similar write_begin()/write_end() * but keeping in mind that i_size will not change */ - *err = __block_write_begin(pagep[0], from, from + replaced_size, + *err = __block_write_begin(pagep[0], from, replaced_size, ext4_get_block); if (!*err) *err = block_commit_write(pagep[0], from, from + replaced_size);