ublk_dispatch_req() currently handles 3 different cases: incoming ublk
requests that don't need to wait for a data buffer, incoming requests
that do need to wait for a buffer, and resuming those requests once the
buffer is provided. But the call site that provides a data buffer
(UBLK_IO_NEED_GET_DATA) is separate from those for incoming requests.
So simplify the function by splitting the UBLK_IO_NEED_GET_DATA case
into its own function ublk_get_data(). This avoids several redundant
checks in the UBLK_IO_NEED_GET_DATA case, and streamlines the incoming
request cases.
Don't call ublk_fill_io_cmd() for UBLK_IO_NEED_GET_DATA, as it's no
longer necessary to set io->cmd or the UBLK_IO_FLAG_ACTIVE flag for
ublk_dispatch_req().
Since UBLK_IO_NEED_GET_DATA no longer relies on ublk_dispatch_req()
calling io_uring_cmd_done(), return the UBLK_IO_RES_OK status directly
from the ->uring_cmd() handler.
Signed-off-by: Caleb Sander Mateos <csander@xxxxxxxxxxxxxxx>
---
drivers/block/ublk_drv.c | 49 ++++++++++++++++++++++------------------
1 file changed, 27 insertions(+), 22 deletions(-)
diff --git a/drivers/block/ublk_drv.c b/drivers/block/ublk_drv.c
index 90a38a82f8cc..ea63cee1786e 100644
--- a/drivers/block/ublk_drv.c
+++ b/drivers/block/ublk_drv.c
@@ -1210,29 +1210,16 @@ static void ublk_dispatch_req(struct ublk_queue *ubq,
/*
* We have not handled UBLK_IO_NEED_GET_DATA command yet,
* so immediately pass UBLK_IO_RES_NEED_GET_DATA to ublksrv
* and notify it.
*/
- if (!(io->flags & UBLK_IO_FLAG_NEED_GET_DATA)) {
- io->flags |= UBLK_IO_FLAG_NEED_GET_DATA;
- pr_devel("%s: need get data. qid %d tag %d io_flags %x\n",
- __func__, ubq->q_id, req->tag, io->flags);
- ublk_complete_io_cmd(io, UBLK_IO_RES_NEED_GET_DATA,
- issue_flags);
- return;
- }
- /*
- * We have handled UBLK_IO_NEED_GET_DATA command,
- * so clear UBLK_IO_FLAG_NEED_GET_DATA now and just
- * do the copy work.
- */
- io->flags &= ~UBLK_IO_FLAG_NEED_GET_DATA;
- /* update iod->addr because ublksrv may have passed a new io buffer */
- ublk_get_iod(ubq, req->tag)->addr = io->addr;
- pr_devel("%s: update iod->addr: qid %d tag %d io_flags %x addr %llx\n",
- __func__, ubq->q_id, req->tag, io->flags,
- ublk_get_iod(ubq, req->tag)->addr);
+ io->flags |= UBLK_IO_FLAG_NEED_GET_DATA;
+ pr_devel("%s: need get data. qid %d tag %d io_flags %x\n",
+ __func__, ubq->q_id, req->tag, io->flags);
+ ublk_complete_io_cmd(io, UBLK_IO_RES_NEED_GET_DATA,
+ issue_flags);
+ return;
}
ublk_start_io(ubq, req, io);
ublk_complete_io_cmd(io, UBLK_IO_RES_OK, issue_flags);
}
@@ -2041,10 +2028,28 @@ static int ublk_commit_and_fetch(const struct ublk_queue *ubq,
ublk_put_req_ref(ubq, req);
return 0;
}
+static void ublk_get_data(struct ublk_queue *ubq, struct ublk_io *io,
+ struct request *req)
+{
+ /*
+ * We have handled UBLK_IO_NEED_GET_DATA command,
+ * so clear UBLK_IO_FLAG_NEED_GET_DATA now and just
+ * do the copy work.
+ */
+ io->flags &= ~UBLK_IO_FLAG_NEED_GET_DATA;
+ /* update iod->addr because ublksrv may have passed a new io buffer */
+ ublk_get_iod(ubq, req->tag)->addr = io->addr;
+ pr_devel("%s: update iod->addr: qid %d tag %d io_flags %x addr %llx\n",
+ __func__, ubq->q_id, req->tag, io->flags,
+ ublk_get_iod(ubq, req->tag)->addr);
+
+ ublk_start_io(ubq, req, io);
+}
+
static int __ublk_ch_uring_cmd(struct io_uring_cmd *cmd,
unsigned int issue_flags,
const struct ublksrv_io_cmd *ub_cmd)
{
struct ublk_device *ub = cmd->file->private_data;
@@ -2106,14 +2111,14 @@ static int __ublk_ch_uring_cmd(struct io_uring_cmd *cmd,
goto out;
break;
case UBLK_IO_NEED_GET_DATA:
if (!(io->flags & UBLK_IO_FLAG_OWNED_BY_SRV))
goto out;
- ublk_fill_io_cmd(io, cmd, ub_cmd->addr);
+ io->addr = ub_cmd->addr;
req = blk_mq_tag_to_rq(ub->tag_set.tags[ub_cmd->q_id], tag);
- ublk_dispatch_req(ubq, req, issue_flags);
- return -EIOCBQUEUED;
+ ublk_get_data(ubq, io, req);
+ return UBLK_IO_RES_OK;
default:
goto out;
}
ublk_prep_cancel(cmd, issue_flags, ubq, tag);
return -EIOCBQUEUED;
--
2.45.2
