ublk: remove ublk_commit_and_fetch()

Remove ublk_commit_and_fetch() and open code request completion.

Consolidate accesses to struct ublk_io in UBLK_IO_COMMIT_AND_FETCH_REQ. When
the ublk_io daemon task restriction is relaxed in the future, ublk_io will
need to be protected by a lock. Unregister the auto-registered buffer and
complete the request last, as these don't need to happen under the lock.

Signed-off-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20250713143415.2857561-10-ming.lei@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>

diff --git a/drivers/block/ublk_drv.c b/drivers/block/ublk_drv.c
index 1b22fd5f5610df527f84489d5fadc4a55a3b1e85..252cae345b3a0802a361d34e49ec00f33fbc7940 100644 (file)
--- a/drivers/block/ublk_drv.c
+++ b/drivers/block/ublk_drv.c
@@ -714,13 +714,12 @@ static inline void ublk_put_req_ref(struct ublk_io *io, struct request *req)
                __ublk_complete_rq(req);
 }
 
-static inline void ublk_sub_req_ref(struct ublk_io *io, struct request *req)
+static inline bool ublk_sub_req_ref(struct ublk_io *io, struct request *req)
 {
        unsigned sub_refs = UBLK_REFCOUNT_INIT - io->task_registered_buffers;
 
        io->task_registered_buffers = 0;
-       if (refcount_sub_and_test(sub_refs, &io->ref))
-               __ublk_complete_rq(req);
+       return refcount_sub_and_test(sub_refs, &io->ref);
 }
 
 static inline bool ublk_need_get_data(const struct ublk_queue *ubq)
@@ -2243,21 +2242,13 @@ static int ublk_check_commit_and_fetch(const struct ublk_queue *ubq,
        return 0;
 }
 
-static void ublk_commit_and_fetch(const struct ublk_queue *ubq,
-                                 struct ublk_io *io, struct io_uring_cmd *cmd,
-                                 struct request *req, unsigned int issue_flags,
-                                 __u64 zone_append_lba, u16 buf_idx)
+static bool ublk_need_complete_req(const struct ublk_queue *ubq,
+                                  struct ublk_io *io,
+                                  struct request *req)
 {
-       if (buf_idx != UBLK_INVALID_BUF_IDX)
-               io_buffer_unregister_bvec(cmd, buf_idx, issue_flags);
-
-       if (req_op(req) == REQ_OP_ZONE_APPEND)
-               req->__sector = zone_append_lba;
-
        if (ublk_need_req_ref(ubq))
-               ublk_sub_req_ref(io, req);
-       else
-               __ublk_complete_rq(req);
+               return ublk_sub_req_ref(io, req);
+       return true;
 }
 
 static bool ublk_get_data(const struct ublk_queue *ubq, struct ublk_io *io,
@@ -2290,6 +2281,7 @@ static int __ublk_ch_uring_cmd(struct io_uring_cmd *cmd,
        unsigned tag = ub_cmd->tag;
        struct request *req;
        int ret;
+       bool compl;
 
        pr_devel("%s: received: cmd op %d queue %d tag %d result %d\n",
                        __func__, cmd->cmd_op, ub_cmd->q_id, tag,
@@ -2367,8 +2359,16 @@ static int __ublk_ch_uring_cmd(struct io_uring_cmd *cmd,
                io->res = ub_cmd->result;
                req = ublk_fill_io_cmd(io, cmd);
                ret = ublk_config_io_buf(ubq, io, cmd, ub_cmd->addr, &buf_idx);
-               ublk_commit_and_fetch(ubq, io, cmd, req, issue_flags,
-                                     ub_cmd->zone_append_lba, buf_idx);
+               compl = ublk_need_complete_req(ubq, io, req);
+
+               /* can't touch 'ublk_io' any more */
+               if (buf_idx != UBLK_INVALID_BUF_IDX)
+                       io_buffer_unregister_bvec(cmd, buf_idx, issue_flags);
+               if (req_op(req) == REQ_OP_ZONE_APPEND)
+                       req->__sector = ub_cmd->zone_append_lba;
+               if (compl)
+                       __ublk_complete_rq(req);
+
                if (ret)
                        goto out;
                break;