On 6/30/23 9:25?AM, David Howells wrote:
> diff --git a/io_uring/rw.c b/io_uring/rw.c
> index 1bce2208b65c..1cade1567162 100644
> --- a/io_uring/rw.c
> +++ b/io_uring/rw.c
> @@ -655,12 +655,13 @@ static bool need_complete_io(struct io_kiocb *req)
> S_ISBLK(file_inode(req->file)->i_mode);
> }
>
> -static int io_rw_init_file(struct io_kiocb *req, fmode_t mode)
> +static int io_rw_init_file(struct io_kiocb *req, unsigned int io_direction)
> {
> struct io_rw *rw = io_kiocb_to_cmd(req, struct io_rw);
> struct kiocb *kiocb = &rw->kiocb;
> struct io_ring_ctx *ctx = req->ctx;
> struct file *file = req->file;
> + fmode_t mode = (io_direction == WRITE) ? FMODE_WRITE : FMODE_READ;
> int ret;
>
> if (unlikely(!file || !(file->f_mode & mode)))
Not ideal to add a branch here, probably better to just pass in both?
> @@ -870,7 +871,7 @@ int io_write(struct io_kiocb *req, unsigned int issue_flags)
> iov_iter_restore(&s->iter, &s->iter_state);
> iovec = NULL;
> }
> - ret = io_rw_init_file(req, FMODE_WRITE);
> + ret = io_rw_init_file(req, WRITE);
> if (unlikely(ret)) {
> kfree(iovec);
> return ret;
> @@ -914,7 +915,6 @@ int io_write(struct io_kiocb *req, unsigned int issue_flags)
> __sb_writers_release(file_inode(req->file)->i_sb,
> SB_FREEZE_WRITE);
> }
> - kiocb->ki_flags |= IOCB_WRITE;
>
> if (likely(req->file->f_op->write_iter))
> ret2 = call_write_iter(req->file, kiocb, &s->iter);
>
One concern here is that we're using IOCB_WRITE here to tell if
sb_start_write() has been done or not, and hence whether
kiocb_end_write() needs to be called. You know set it earlier, which
means if we get a failure if we need to setup async data, then we know
have IOCB_WRITE set at that point even though we did not call
sb_start_write().
--
Jens Axboe
