On Nov 26, 2019 / 15:44, Jaegeuk Kim wrote: > On 11/26, Damien Le Moal wrote: > > f2fs_preallocate_blocks() identifies direct IOs using the IOCB_DIRECT > > flag for a kiocb structure. However, the file system direct IO handler > > function f2fs_direct_IO() may have decided that a direct IO has to be > > exececuted as a buffered IO using the function f2fs_force_buffered_io(). > > This is the case for instance for volumes including zoned block device > > and for unaligned write IOs with LFS mode enabled. > > > > These 2 different methods of identifying direct IOs can result in > > inconsistencies generating stale data access for direct reads after a > > direct IO write that is treated as a buffered write. Fix this > > inconsistency by combining the IOCB_DIRECT flag test with the result > > of f2fs_force_buffered_io(). > > > > Reported-by: Javier Gonzalez <[email protected]> > > Signed-off-by: Damien Le Moal <[email protected]> > > --- > > fs/f2fs/data.c | 4 +++- > > 1 file changed, 3 insertions(+), 1 deletion(-) > > > > diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c > > index 5755e897a5f0..8ac2d3b70022 100644 > > --- a/fs/f2fs/data.c > > +++ b/fs/f2fs/data.c > > @@ -1073,6 +1073,8 @@ int f2fs_preallocate_blocks(struct kiocb *iocb, > > struct iov_iter *from) > > int flag; > > int err = 0; > > bool direct_io = iocb->ki_flags & IOCB_DIRECT; > > + bool do_direct_io = direct_io && > > + !f2fs_force_buffered_io(inode, iocb, from); > > > > /* convert inline data for Direct I/O*/ > > if (direct_io) { > > @@ -1081,7 +1083,7 @@ int f2fs_preallocate_blocks(struct kiocb *iocb, > > struct iov_iter *from) > > return err; > > } > > > > - if (direct_io && allow_outplace_dio(inode, iocb, from)) > > + if (do_direct_io && allow_outplace_dio(inode, iocb, from)) > > It seems f2fs_force_buffered_io() includes allow_outplace_dio(). > > How about this?
Thanks. I confirmed that the issue is gone with your patch. Tested-by: Shin'ichiro Kawasaki <[email protected]> > --- > fs/f2fs/data.c | 13 ------------- > fs/f2fs/file.c | 35 +++++++++++++++++++++++++---------- > 2 files changed, 25 insertions(+), 23 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 c0560d62dbee..6b32ac6c3382 100644 > --- a/fs/f2fs/file.c > +++ b/fs/f2fs/file.c > @@ -3386,18 +3386,33 @@ 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); > + goto write; > + } > > - err = f2fs_preallocate_blocks(iocb, from); > - if (err) { > - clear_inode_flag(inode, FI_NO_PREALLOC); > - inode_unlock(inode); > - ret = err; > - goto out; > - } > + if (is_inode_flag_set(inode, FI_NO_PREALLOC)) > + goto write; > + > + if (iocb->ki_flags & IOCB_DIRECT) { > + /* convert inline data for Direct I/O*/ > + err = f2fs_convert_inline_inode(inode); > + if (err) > + goto out_err; > + > + if (!f2fs_force_buffered_io(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); > > -- > 2.19.0.605.g01d371f741-goog > -- Best Regards, Shin'ichiro Kawasaki _______________________________________________ Linux-f2fs-devel mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/linux-f2fs-devel
