On 7/29/26 17:52, Anuj gupta wrote:
On Wed, Jul 29, 2026 at 7:37 PM Pavel Begunkov <[email protected]> wrote:
+static int io_import_dmabuf(struct io_kiocb *req,
+ int ddir, struct iov_iter *iter,
+ struct io_mapped_ubuf *imu,
+ size_t len, size_t offset,
+ unsigned issue_flags)
+{
+ struct io_regbuf_dma *db = imu->priv;
+ struct dma_buf_io_map *map;
+
+ if (!IS_ENABLED(CONFIG_DMA_SHARED_BUFFER))
+ return -EOPNOTSUPP;
+ if (!len)
+ return -EFAULT;
+ if (req->file != db->target_file)
+ return -EBADF;
+
+ if (req->flags & REQ_F_DROP_DMABUF) {
+ map = req->dmabuf_map;
+ goto init_iter;
+ }
O_DIRECT is checked only during registration; we should recheck
(file->f_flags & O_DIRECT) per request.
Nobody should be able to clear O_DIRECT, unless I missed something?
And fwiw, io_uring wouldn't be the right place to do it.
fcntl(fd, F_SETFL, flags & ~O_DIRECT) on an already registered, already
open fd succeeds. The consequence is that subsequent I/Os switch to
Very exciting.
buffered I/O and cause silent data loss. Something on this path needs
to reject this combination.
Yeah, I'll fix it, thanks
--
Pavel Begunkov
