Hey Juan,
I think we're close, please ack this if it looks ok. Thanks, Alex On Thu, 9 Feb 2023 21:20:35 +0200 Avihai Horon <avih...@nvidia.com> wrote: > Add new function qemu_file_get_to_fd() that allows reading data from > QEMUFile and writing it straight into a given fd. > > This will be used later in VFIO migration code. > > Signed-off-by: Avihai Horon <avih...@nvidia.com> > Reviewed-by: Vladimir Sementsov-Ogievskiy <vsement...@yandex-team.ru> > Reviewed-by: Cédric Le Goater <c...@redhat.com> > --- > migration/qemu-file.h | 1 + > migration/qemu-file.c | 34 ++++++++++++++++++++++++++++++++++ > 2 files changed, 35 insertions(+) > > diff --git a/migration/qemu-file.h b/migration/qemu-file.h > index fa13d04d78..9d0155a2a1 100644 > --- a/migration/qemu-file.h > +++ b/migration/qemu-file.h > @@ -148,6 +148,7 @@ int qemu_file_shutdown(QEMUFile *f); > QEMUFile *qemu_file_get_return_path(QEMUFile *f); > void qemu_fflush(QEMUFile *f); > void qemu_file_set_blocking(QEMUFile *f, bool block); > +int qemu_file_get_to_fd(QEMUFile *f, int fd, size_t size); > > void ram_control_before_iterate(QEMUFile *f, uint64_t flags); > void ram_control_after_iterate(QEMUFile *f, uint64_t flags); > diff --git a/migration/qemu-file.c b/migration/qemu-file.c > index 2d5f74ffc2..102ab3b439 100644 > --- a/migration/qemu-file.c > +++ b/migration/qemu-file.c > @@ -940,3 +940,37 @@ QIOChannel *qemu_file_get_ioc(QEMUFile *file) > { > return file->ioc; > } > + > +/* > + * Read size bytes from QEMUFile f and write them to fd. > + */ > +int qemu_file_get_to_fd(QEMUFile *f, int fd, size_t size) > +{ > + while (size) { > + size_t pending = f->buf_size - f->buf_index; > + ssize_t rc; > + > + if (!pending) { > + rc = qemu_fill_buffer(f); > + if (rc < 0) { > + return rc; > + } > + if (rc == 0) { > + return -EIO; > + } > + continue; > + } > + > + rc = write(fd, f->buf + f->buf_index, MIN(pending, size)); > + if (rc < 0) { > + return -errno; > + } > + if (rc == 0) { > + return -EIO; > + } > + f->buf_index += rc; > + size -= rc; > + } > + > + return 0; > +}