> On Thu, 17 Apr 2014, Namjae Jeon wrote: > > > Date: Thu, 17 Apr 2014 07:27:45 +0900 > > From: Namjae Jeon <namjae.jeon@xxxxxxxxxxx> > > To: Theodore Ts'o <tytso@xxxxxxx> > > Cc: linux-ext4 <linux-ext4@xxxxxxxxxxxxxxx>, > > 'Lukáš Czerner' <lczerner@xxxxxxxxxx> > > Subject: [PATCH 1/3] ext4: fix COLLAPSE_RANGE failure issue on ext4 with 1KB > > block size > > > > From: Namjae Jeon <namjae.jeon@xxxxxxxxxxx> > > > > When formatting with 1KB or 2KB(not aligned with PAGE SIZE) block size, > > xfstests generic/075 and 091 are failing. The offset supplied to function > > truncate_pagecache_range is block size aligned. In this function start offset > > is re-aligned to PAGE_SIZE by rounding_up to the next page boundary. > > Due to this rounding up, old data remains in the page cache when blocksize is > > less than page size and start offset is not aligned with page size. > > In case of collapse range, we need to align start offset to page size boundary > > by doing a round down operation instead of round up. > > Great, thanks for finding it. > > > > > Signed-off-by: Namjae Jeon <namjae.jeon@xxxxxxxxxxx> > > Signed-off-by: Ashish Sangwan <a.sangwan@xxxxxxxxxxx> > > --- > > fs/ext4/extents.c | 11 +++++++---- > > 1 file changed, 7 insertions(+), 4 deletions(-) > > > > diff --git a/fs/ext4/extents.c b/fs/ext4/extents.c > > index 1bb3e4b..f386dd6 100644 > > --- a/fs/ext4/extents.c > > +++ b/fs/ext4/extents.c > > @@ -5404,8 +5404,8 @@ int ext4_collapse_range(struct inode *inode, loff_t offset, loff_t len) > > struct super_block *sb = inode->i_sb; > > ext4_lblk_t punch_start, punch_stop; > > handle_t *handle; > > - unsigned int credits; > > - loff_t new_size; > > + unsigned int credits, rounding; > > + loff_t new_size, ioffset; > > int ret; > > > > /* Collapse range works only on fs block size aligned offsets. */ > > @@ -5428,8 +5428,11 @@ int ext4_collapse_range(struct inode *inode, loff_t offset, loff_t len) > > return ret; > > } > > > > + rounding = max_t(uint, 1 << EXT4_BLOCK_SIZE_BITS(sb), PAGE_CACHE_SIZE); > > + ioffset = offset & ~(rounding - 1); > > That looks like you're expecting that block size might be bigger > than page size. That's definitely not the case at the moment as we > can not have block size > page size. There is a discussion to > support this in the future, but even when the infrastructure is done > we would have to revisit the code anyway. So I do not think this is > needed. Just always round it down to PAGE_SIZE (since that's what > truncate_pagecache is actually using) Right :), I will change it. > > > + > > /* Write out all dirty pages */ > > - ret = filemap_write_and_wait_range(inode->i_mapping, offset, -1); > > + ret = filemap_write_and_wait_range(inode->i_mapping, ioffset, -1); > > if (ret) > > return ret; > > > > @@ -5451,7 +5454,7 @@ int ext4_collapse_range(struct inode *inode, loff_t offset, loff_t len) > > goto out_mutex; > > } > > > > - truncate_pagecache_range(inode, offset, -1); > > + truncate_pagecache_range(inode, ioffset, -1); > > As I mentioned in a different email we can just use > truncate_pagecache(). In fact we should use it because we want to > remove private COWed pages as well I think. Okay, If you send the updated your patch, I will create the patch base on your patch again. Thanks :) > > Thanks! > -Lukas > > > > > /* Wait for existing dio to complete */ > > ext4_inode_block_unlocked_dio(inode); > > -- To unsubscribe from this list: send the line "unsubscribe linux-ext4" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
