+ CC: linux-xfs@xxxxxxxxxxxxxxx On Mon, Sep 09, 2019 at 09:19:31AM +1000, Matthew Bobrowski wrote: > This patch modifies the calling convention for the iomap ->end_io() > callback. Rather than passing either dio->error or dio->size as the > 'size' argument, we instead pass both dio->error and dio->size values > separately. > > In the instance that an error occurred during a write, we currently > cannot determine whether any blocks have been allocated beyond the > current EOF and data has subsequently been written to these blocks > within the ->end_io() callback. As a result, we cannot judge whether > we should take the truncate failed write path. Having both dio->error > and dio->size will allow us to perform such checks within this > callback. > > Signed-off-by: Matthew Bobrowski <mbobrowski@xxxxxxxxxxxxxx> Please note, this patch is now part of the recent end_io improvements posted through by Christoph, and can be found here: https://git.kernel.org/pub/scm/fs/xfs/xfs-linux.git/commit/?h=iomap-5.4-merge&id=db10bd824bc0353702231f1294b58903cb66bac7. > --- > fs/iomap/direct-io.c | 9 +++------ > fs/xfs/xfs_file.c | 8 +++++--- > include/linux/iomap.h | 4 ++-- > 3 files changed, 10 insertions(+), 11 deletions(-) > > diff --git a/fs/iomap/direct-io.c b/fs/iomap/direct-io.c > index 10517cea9682..2ccf1c6460d4 100644 > --- a/fs/iomap/direct-io.c > +++ b/fs/iomap/direct-io.c > @@ -77,13 +77,10 @@ static ssize_t iomap_dio_complete(struct iomap_dio *dio) > loff_t offset = iocb->ki_pos; > ssize_t ret; > > - if (dio->end_io) { > - ret = dio->end_io(iocb, > - dio->error ? dio->error : dio->size, > - dio->flags); > - } else { > + if (dio->end_io) > + ret = dio->end_io(iocb, dio->size, dio->error, dio->flags); > + else > ret = dio->error; > - } > > if (likely(!ret)) { > ret = dio->size; > diff --git a/fs/xfs/xfs_file.c b/fs/xfs/xfs_file.c > index 28101bbc0b78..d49759008c54 100644 > --- a/fs/xfs/xfs_file.c > +++ b/fs/xfs/xfs_file.c > @@ -369,21 +369,23 @@ static int > xfs_dio_write_end_io( > struct kiocb *iocb, > ssize_t size, > + int error, > unsigned flags) > { > struct inode *inode = file_inode(iocb->ki_filp); > struct xfs_inode *ip = XFS_I(inode); > loff_t offset = iocb->ki_pos; > unsigned int nofs_flag; > - int error = 0; > > trace_xfs_end_io_direct_write(ip, offset, size); > > if (XFS_FORCED_SHUTDOWN(ip->i_mount)) > return -EIO; > > - if (size <= 0) > - return size; > + if (error) > + return error; > + if (!size) > + return 0; > > /* > * Capture amount written on completion as we can't reliably account > diff --git a/include/linux/iomap.h b/include/linux/iomap.h > index bc499ceae392..d983cdcf2e72 100644 > --- a/include/linux/iomap.h > +++ b/include/linux/iomap.h > @@ -188,8 +188,8 @@ sector_t iomap_bmap(struct address_space *mapping, sector_t bno, > */ > #define IOMAP_DIO_UNWRITTEN (1 << 0) /* covers unwritten extent(s) */ > #define IOMAP_DIO_COW (1 << 1) /* covers COW extent(s) */ > -typedef int (iomap_dio_end_io_t)(struct kiocb *iocb, ssize_t ret, > - unsigned flags); > +typedef int (iomap_dio_end_io_t)(struct kiocb *iocb, ssize_t size, > + int error, unsigned int flags); > ssize_t iomap_dio_rw(struct kiocb *iocb, struct iov_iter *iter, > const struct iomap_ops *ops, iomap_dio_end_io_t end_io); > int iomap_dio_iopoll(struct kiocb *kiocb, bool spin); > -- > 2.20.1 >