From 7e8b12c60ad38fb90a162df4e6fc120e3bee104e Mon Sep 17 00:00:00 2001 From: Dmitry Monakhov Date: Thu, 11 Apr 2013 23:24:58 -0400 Subject: [PATCH] ext4: defragmentation code cleanup - 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 Signed-off-by: "Theodore Ts'o" Reviewed-by: Akira Fujita --- fs/ext4/move_extent.c | 11 +++++++++-- 1 file changed, 9 insertions(+), 2 deletions(-) diff --git a/fs/ext4/move_extent.c b/fs/ext4/move_extent.c index 661f4ce688ec..309ca899a731 100644 --- a/fs/ext4/move_extent.c +++ b/fs/ext4/move_extent.c @@ -739,6 +739,7 @@ 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; @@ -816,7 +817,13 @@ 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]; @@ -1034,7 +1041,7 @@ move_extent_per_page(struct file *o_filp, struct inode *donor_inode, } /* 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);