ext4: truncate block allocated on a failed ext4_write_begin 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" diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c index 5a595af..a1e235d 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))