From 47501f87c61ad2aa234add63e1ae231521dbc3f5 Mon Sep 17 00:00:00 2001 From: Jaegeuk Kim Date: Tue, 26 Nov 2019 15:01:42 -0800 Subject: [PATCH] f2fs: preallocate DIO blocks when forcing buffered_io MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit The previous preallocation and DIO decision like below. allow_outplace_dio !allow_outplace_dio f2fs_force_buffered_io (*) No_Prealloc / Buffered_IO Prealloc / Buffered_IO !f2fs_force_buffered_io No_Prealloc / DIO Prealloc / DIO But, Javier reported Case (*) where zoned device bypassed preallocation but fell back to buffered writes in f2fs_direct_IO(), resulting in stale data being read. In order to fix the issue, actually we need to preallocate blocks whenever we fall back to buffered IO like this. No change is made in the other cases. allow_outplace_dio !allow_outplace_dio f2fs_force_buffered_io (*) Prealloc / Buffered_IO Prealloc / Buffered_IO !f2fs_force_buffered_io No_Prealloc / DIO Prealloc / DIO Reported-and-tested-by: Javier Gonzalez Signed-off-by: Damien Le Moal Tested-by: Shin'ichiro Kawasaki Reviewed-by: Chao Yu Reviewed-by: Javier González Signed-off-by: Jaegeuk Kim --- fs/f2fs/data.c | 13 ------------- fs/f2fs/file.c | 45 ++++++++++++++++++++++++++++++++++----------- 2 files changed, 34 insertions(+), 24 deletions(-) diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c index a034cd0ce021..fc40a72f7827 100644 --- a/fs/f2fs/data.c +++ b/fs/f2fs/data.c @@ -1180,19 +1180,6 @@ int f2fs_preallocate_blocks(struct kiocb *iocb, struct iov_iter *from) int err = 0; bool direct_io = iocb->ki_flags & IOCB_DIRECT; - /* convert inline data for Direct I/O*/ - if (direct_io) { - err = f2fs_convert_inline_inode(inode); - if (err) - return err; - } - - if (direct_io && allow_outplace_dio(inode, iocb, from)) - return 0; - - if (is_inode_flag_set(inode, FI_NO_PREALLOC)) - return 0; - map.m_lblk = F2FS_BLK_ALIGN(iocb->ki_pos); map.m_len = F2FS_BYTES_TO_BLK(iocb->ki_pos + iov_iter_count(from)); if (map.m_len > map.m_lblk) diff --git a/fs/f2fs/file.c b/fs/f2fs/file.c index 85af112e868d..e7fcbd8c23f4 100644 --- a/fs/f2fs/file.c +++ b/fs/f2fs/file.c @@ -3389,18 +3389,41 @@ static ssize_t f2fs_file_write_iter(struct kiocb *iocb, struct iov_iter *from) ret = -EAGAIN; goto out; } - } else { - preallocated = true; - target_size = iocb->ki_pos + iov_iter_count(from); - - err = f2fs_preallocate_blocks(iocb, from); - if (err) { - clear_inode_flag(inode, FI_NO_PREALLOC); - inode_unlock(inode); - ret = err; - goto out; - } + goto write; } + + if (is_inode_flag_set(inode, FI_NO_PREALLOC)) + goto write; + + if (iocb->ki_flags & IOCB_DIRECT) { + /* + * Convert inline data for Direct I/O before entering + * f2fs_direct_IO(). + */ + err = f2fs_convert_inline_inode(inode); + if (err) + goto out_err; + /* + * If force_buffere_io() is true, we have to allocate + * blocks all the time, since f2fs_direct_IO will fall + * back to buffered IO. + */ + if (!f2fs_force_buffered_io(inode, iocb, from) && + allow_outplace_dio(inode, iocb, from)) + goto write; + } + preallocated = true; + target_size = iocb->ki_pos + iov_iter_count(from); + + err = f2fs_preallocate_blocks(iocb, from); + if (err) { +out_err: + clear_inode_flag(inode, FI_NO_PREALLOC); + inode_unlock(inode); + ret = err; + goto out; + } +write: ret = __generic_file_write_iter(iocb, from); clear_inode_flag(inode, FI_NO_PREALLOC);