selftests: ublk: add ublk_io_buf_idx() for returning io buffer index

Since UBLK_F_PER_IO_DAEMON is added, io buffer index may depend on current
thread because the common way is to use per-pthread io_ring_ctx for issuing
ublk uring_cmd.

Add one helper for returning io buffer index, so we can hide the buffer
index implementation details for target code.

Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

5 files changed, 33 insertions, 20 deletions

diff --git a/tools/testing/selftests/ublk/file_backed.c b/tools/testing/selftests/ublk/file_backed.c
index 889047bd8fa3..228af2580ac6 100644
--- a/tools/testing/selftests/ublk/file_backed.c
+++ b/tools/testing/selftests/ublk/file_backed.c
@@ -39,6 +39,7 @@ static int loop_queue_tgt_rw_io(struct ublk_thread *t, struct ublk_queue *q,
 	__u32 len = iod->nr_sectors << 9;
 	struct io_uring_sqe *sqe[3];
 	void *addr = io->buf_addr;
+	unsigned short buf_index = ublk_io_buf_idx(t, q, tag);
 
 	if (iod->op_flags & UBLK_IO_F_INTEGRITY) {
 		ublk_io_alloc_sqes(t, sqe, 1);
@@ -62,7 +63,7 @@ static int loop_queue_tgt_rw_io(struct ublk_thread *t, struct ublk_queue *q,
 				len,
 				offset);
 		if (auto_zc)
-			sqe[0]->buf_index = tag;
+			sqe[0]->buf_index = buf_index;
 		io_uring_sqe_set_flags(sqe[0], IOSQE_FIXED_FILE);
 		/* bit63 marks us as tgt io */
 		sqe[0]->user_data = build_user_data(tag, ublk_op, 0, q->q_id, 1);
@@ -71,7 +72,7 @@ static int loop_queue_tgt_rw_io(struct ublk_thread *t, struct ublk_queue *q,
 
 	ublk_io_alloc_sqes(t, sqe, 3);
 
-	io_uring_prep_buf_register(sqe[0], q, tag, q->q_id, io->buf_index);
+	io_uring_prep_buf_register(sqe[0], q, tag, q->q_id, buf_index);
 	sqe[0]->flags |= IOSQE_CQE_SKIP_SUCCESS | IOSQE_IO_HARDLINK;
 	sqe[0]->user_data = build_user_data(tag,
 			ublk_cmd_op_nr(sqe[0]->cmd_op), 0, q->q_id, 1);
@@ -79,11 +80,11 @@ static int loop_queue_tgt_rw_io(struct ublk_thread *t, struct ublk_queue *q,
 	io_uring_prep_rw(op, sqe[1], ublk_get_registered_fd(q, 1) /*fds[1]*/, 0,
 			len,
 			offset);
-	sqe[1]->buf_index = tag;
+	sqe[1]->buf_index = buf_index;
 	sqe[1]->flags |= IOSQE_FIXED_FILE | IOSQE_IO_HARDLINK;
 	sqe[1]->user_data = build_user_data(tag, ublk_op, 0, q->q_id, 1);
 
-	io_uring_prep_buf_unregister(sqe[2], q, tag, q->q_id, io->buf_index);
+	io_uring_prep_buf_unregister(sqe[2], q, tag, q->q_id, buf_index);
 	sqe[2]->user_data = build_user_data(tag, ublk_cmd_op_nr(sqe[2]->cmd_op), 0, q->q_id, 1);
 
 	return !!(iod->op_flags & UBLK_IO_F_INTEGRITY) + 2;
diff --git a/tools/testing/selftests/ublk/kublk.c b/tools/testing/selftests/ublk/kublk.c
index e98999bea9b1..9b6f1cd04dc4 100644
--- a/tools/testing/selftests/ublk/kublk.c
+++ b/tools/testing/selftests/ublk/kublk.c
@@ -605,16 +605,17 @@ static void ublk_dev_unprep(struct ublk_dev *dev)
 	close(dev->fds[0]);
 }
 
-static void ublk_set_auto_buf_reg(const struct ublk_queue *q,
+static void ublk_set_auto_buf_reg(const struct ublk_thread *t,
+				  const struct ublk_queue *q,
 				  struct io_uring_sqe *sqe,
 				  unsigned short tag)
 {
 	struct ublk_auto_buf_reg buf = {};
 
 	if (q->tgt_ops->buf_index)
-		buf.index = q->tgt_ops->buf_index(q, tag);
+		buf.index = q->tgt_ops->buf_index(t, q, tag);
 	else
-		buf.index = q->ios[tag].buf_index;
+		buf.index = ublk_io_buf_idx(t, q, tag);
 
 	if (ublk_queue_auto_zc_fallback(q))
 		buf.flags = UBLK_AUTO_BUF_REG_FALLBACK;
@@ -730,7 +731,7 @@ int ublk_queue_io_cmd(struct ublk_thread *t, struct ublk_io *io)
 		cmd->addr	= 0;
 
 	if (ublk_queue_use_auto_zc(q))
-		ublk_set_auto_buf_reg(q, sqe[0], io->tag);
+		ublk_set_auto_buf_reg(t, q, sqe[0], io->tag);
 
 	user_data = build_user_data(io->tag, _IOC_NR(cmd_op), 0, q->q_id, 0);
 	io_uring_sqe_set_data64(sqe[0], user_data);
diff --git a/tools/testing/selftests/ublk/kublk.h b/tools/testing/selftests/ublk/kublk.h
index 48634d29c084..311a75da9b21 100644
--- a/tools/testing/selftests/ublk/kublk.h
+++ b/tools/testing/selftests/ublk/kublk.h
@@ -150,7 +150,8 @@ struct ublk_tgt_ops {
 	void (*usage)(const struct ublk_tgt_ops *ops);
 
 	/* return buffer index for UBLK_F_AUTO_BUF_REG */
-	unsigned short (*buf_index)(const struct ublk_queue *, int tag);
+	unsigned short (*buf_index)(const struct ublk_thread *t,
+			const struct ublk_queue *, int tag);
 };
 
 struct ublk_tgt {
@@ -393,6 +394,13 @@ static inline void ublk_set_sqe_cmd_op(struct io_uring_sqe *sqe, __u32 cmd_op)
 	addr[1] = 0;
 }
 
+static inline unsigned short ublk_io_buf_idx(const struct ublk_thread *t,
+					     const struct ublk_queue *q,
+					     unsigned tag)
+{
+	return q->ios[tag].buf_index;
+}
+
 static inline struct ublk_io *ublk_get_io(struct ublk_queue *q, unsigned tag)
 {
 	return &q->ios[tag];
diff --git a/tools/testing/selftests/ublk/null.c b/tools/testing/selftests/ublk/null.c
index 3aa162f08476..7656888f4149 100644
--- a/tools/testing/selftests/ublk/null.c
+++ b/tools/testing/selftests/ublk/null.c
@@ -44,12 +44,12 @@ static int ublk_null_tgt_init(const struct dev_ctx *ctx, struct ublk_dev *dev)
 }
 
 static void __setup_nop_io(int tag, const struct ublksrv_io_desc *iod,
-		struct io_uring_sqe *sqe, int q_id)
+		struct io_uring_sqe *sqe, int q_id, unsigned buf_idx)
 {
 	unsigned ublk_op = ublksrv_get_op(iod);
 
 	io_uring_prep_nop(sqe);
-	sqe->buf_index = tag;
+	sqe->buf_index = buf_idx;
 	sqe->flags |= IOSQE_FIXED_FILE;
 	sqe->rw_flags = IORING_NOP_FIXED_BUFFER | IORING_NOP_INJECT_RESULT;
 	sqe->len = iod->nr_sectors << 9; 	/* injected result */
@@ -61,18 +61,19 @@ static int null_queue_zc_io(struct ublk_thread *t, struct ublk_queue *q,
 {
 	const struct ublksrv_io_desc *iod = ublk_get_iod(q, tag);
 	struct io_uring_sqe *sqe[3];
+	unsigned short buf_idx = ublk_io_buf_idx(t, q, tag);
 
 	ublk_io_alloc_sqes(t, sqe, 3);
 
-	io_uring_prep_buf_register(sqe[0], q, tag, q->q_id, ublk_get_io(q, tag)->buf_index);
+	io_uring_prep_buf_register(sqe[0], q, tag, q->q_id, buf_idx);
 	sqe[0]->user_data = build_user_data(tag,
 			ublk_cmd_op_nr(sqe[0]->cmd_op), 0, q->q_id, 1);
 	sqe[0]->flags |= IOSQE_CQE_SKIP_SUCCESS | IOSQE_IO_HARDLINK;
 
-	__setup_nop_io(tag, iod, sqe[1], q->q_id);
+	__setup_nop_io(tag, iod, sqe[1], q->q_id, buf_idx);
 	sqe[1]->flags |= IOSQE_IO_HARDLINK;
 
-	io_uring_prep_buf_unregister(sqe[2], q, tag, q->q_id, ublk_get_io(q, tag)->buf_index);
+	io_uring_prep_buf_unregister(sqe[2], q, tag, q->q_id, buf_idx);
 	sqe[2]->user_data = build_user_data(tag, ublk_cmd_op_nr(sqe[2]->cmd_op), 0, q->q_id, 1);
 
 	// buf register is marked as IOSQE_CQE_SKIP_SUCCESS
@@ -86,7 +87,7 @@ static int null_queue_auto_zc_io(struct ublk_thread *t, struct ublk_queue *q,
 	struct io_uring_sqe *sqe[1];
 
 	ublk_io_alloc_sqes(t, sqe, 1);
-	__setup_nop_io(tag, iod, sqe[0], q->q_id);
+	__setup_nop_io(tag, iod, sqe[0], q->q_id, ublk_io_buf_idx(t, q, tag));
 	return 1;
 }
 
@@ -137,11 +138,12 @@ static int ublk_null_queue_io(struct ublk_thread *t, struct ublk_queue *q,
  * return invalid buffer index for triggering auto buffer register failure,
  * then UBLK_IO_RES_NEED_REG_BUF handling is covered
  */
-static unsigned short ublk_null_buf_index(const struct ublk_queue *q, int tag)
+static unsigned short ublk_null_buf_index(const struct ublk_thread *t,
+		const struct ublk_queue *q, int tag)
 {
 	if (ublk_queue_auto_zc_fallback(q))
 		return (unsigned short)-1;
-	return q->ios[tag].buf_index;
+	return ublk_io_buf_idx(t, q, tag);
 }
 
 const struct ublk_tgt_ops null_tgt_ops = {
diff --git a/tools/testing/selftests/ublk/stripe.c b/tools/testing/selftests/ublk/stripe.c
index b967447fe591..dca819f5366e 100644
--- a/tools/testing/selftests/ublk/stripe.c
+++ b/tools/testing/selftests/ublk/stripe.c
@@ -135,6 +135,7 @@ static int stripe_queue_tgt_rw_io(struct ublk_thread *t, struct ublk_queue *q,
 	struct ublk_io *io = ublk_get_io(q, tag);
 	int i, extra = zc ? 2 : 0;
 	void *base = io->buf_addr;
+	unsigned short buf_idx = ublk_io_buf_idx(t, q, tag);
 
 	io->private_data = s;
 	calculate_stripe_array(conf, iod, s, base);
@@ -142,7 +143,7 @@ static int stripe_queue_tgt_rw_io(struct ublk_thread *t, struct ublk_queue *q,
 	ublk_io_alloc_sqes(t, sqe, s->nr + extra);
 
 	if (zc) {
-		io_uring_prep_buf_register(sqe[0], q, tag, q->q_id, io->buf_index);
+		io_uring_prep_buf_register(sqe[0], q, tag, q->q_id, buf_idx);
 		sqe[0]->flags |= IOSQE_CQE_SKIP_SUCCESS | IOSQE_IO_HARDLINK;
 		sqe[0]->user_data = build_user_data(tag,
 			ublk_cmd_op_nr(sqe[0]->cmd_op), 0, q->q_id, 1);
@@ -158,7 +159,7 @@ static int stripe_queue_tgt_rw_io(struct ublk_thread *t, struct ublk_queue *q,
 				t->start << 9);
 		io_uring_sqe_set_flags(sqe[i], IOSQE_FIXED_FILE);
 		if (auto_zc || zc) {
-			sqe[i]->buf_index = tag;
+			sqe[i]->buf_index = buf_idx;
 			if (zc)
 				sqe[i]->flags |= IOSQE_IO_HARDLINK;
 		}
@@ -168,7 +169,7 @@ static int stripe_queue_tgt_rw_io(struct ublk_thread *t, struct ublk_queue *q,
 	if (zc) {
 		struct io_uring_sqe *unreg = sqe[s->nr + 1];
 
-		io_uring_prep_buf_unregister(unreg, q, tag, q->q_id, io->buf_index);
+		io_uring_prep_buf_unregister(unreg, q, tag, q->q_id, buf_idx);
 		unreg->user_data = build_user_data(
 			tag, ublk_cmd_op_nr(unreg->cmd_op), 0, q->q_id, 1);
 	}