[PATCH V2 00/11] ublk: cleanup & improvement & zc follow-up

[PATCH V2 00/11] ublk: cleanup & improvement & zc follow-up

[Ming Lei]

Hello Jens,

The 1st two fixes ublk_abort_requests(), and adds comment on handling
ubq->canceling.

The 3rd ~ 5th patches are cleanup.

The 6th and 7th are zc-followup.

The 8th & 9th patch implements ->queue_rqs() and improves IOPS by > 10%.

The last two patches are self-test for ->queue_rqs() & segment parameter
change.

V2:
	- use io_uring_cmd_to_pdu() (Uday)
	- improve zc document (Caleb)
	- consolidate segment parameter interface (Caleb)
	- add reviewed-by
	- add one fix and comment on ubq->canceling
	- fix one hang bug in V2


Ming Lei (11):
  ublk: make sure ubq->canceling is set when queue is frozen
  ublk: comment on ubq->canceling handling in ublk_queue_rq()
  ublk: remove two unused fields from 'struct ublk_queue'
  ublk: add helper of ublk_need_map_io()
  ublk: call io_uring_cmd_to_pdu to get uring_cmd pdu
  ublk: add segment parameter
  ublk: document zero copy feature
  ublk: implement ->queue_rqs()
  ublk: rename ublk_rq_task_work_cb as ublk_cmd_tw_cb
  selftests: ublk: add more tests for covering MQ
  selftests: ublk: add test for checking zero copy related parameter

 Documentation/block/ublk.rst                  |  35 ++-
 drivers/block/ublk_drv.c                      | 214 ++++++++++++++----
 include/uapi/linux/ublk_cmd.h                 |  25 ++
 tools/testing/selftests/ublk/Makefile         |   4 +
 tools/testing/selftests/ublk/null.c           |  11 +-
 tools/testing/selftests/ublk/test_common.sh   |   6 +
 .../testing/selftests/ublk/test_generic_02.sh |  44 ++++
 .../testing/selftests/ublk/test_generic_03.sh |  28 +++
 tools/testing/selftests/ublk/test_loop_01.sh  |  14 +-
 tools/testing/selftests/ublk/test_loop_03.sh  |  14 +-
 tools/testing/selftests/ublk/test_loop_05.sh  |  28 +++
 .../testing/selftests/ublk/test_stress_01.sh  |   6 +-
 .../testing/selftests/ublk/test_stress_02.sh  |   6 +-
 .../testing/selftests/ublk/test_stripe_01.sh  |  14 +-
 .../testing/selftests/ublk/test_stripe_03.sh  |  30 +++
 15 files changed, 397 insertions(+), 82 deletions(-)
 create mode 100755 tools/testing/selftests/ublk/test_generic_02.sh
 create mode 100755 tools/testing/selftests/ublk/test_generic_03.sh
 create mode 100755 tools/testing/selftests/ublk/test_loop_05.sh
 create mode 100755 tools/testing/selftests/ublk/test_stripe_03.sh

-- 
2.47.0

[PATCH V2 01/11] ublk: make sure ubq->canceling is set when queue is frozen

[Ming Lei]

Now ublk driver depends on `ubq->canceling` for deciding if the request
can be dispatched via uring_cmd & io_uring_cmd_complete_in_task().

Once ubq->canceling is set, the uring_cmd can be done via ublk_cancel_cmd()
and io_uring_cmd_done().

So set ubq->canceling when queue is frozen, this way makes sure that the
flag can be observed from ublk_queue_rq() reliably, and avoids
use-after-free on uring_cmd.

Fixes: 216c8f5ef0f2 ("ublk: replace monitor with cancelable uring_cmd")
Signed-off-by: Ming Lei <ming.lei@redhat.com>
---
 drivers/block/ublk_drv.c | 39 +++++++++++++++++++++++++++++----------
 1 file changed, 29 insertions(+), 10 deletions(-)

diff --git a/drivers/block/ublk_drv.c b/drivers/block/ublk_drv.c
index c060da409ed8..fbcb7c2ff851 100644
--- a/drivers/block/ublk_drv.c
+++ b/drivers/block/ublk_drv.c
@@ -1446,17 +1446,27 @@ static void ublk_abort_queue(struct ublk_device *ub, struct ublk_queue *ubq)
 	}
 }
 
+/* Must be called when queue is frozen */
+static bool ublk_mark_queue_canceling(struct ublk_queue *ubq)
+{
+	bool canceled;
+
+	spin_lock(&ubq->cancel_lock);
+	canceled = ubq->canceling;
+	if (!canceled)
+		ubq->canceling = true;
+	spin_unlock(&ubq->cancel_lock);
+
+	return canceled;
+}
+
 static bool ublk_abort_requests(struct ublk_device *ub, struct ublk_queue *ubq)
 {
+	bool was_canceled = ubq->canceling;
 	struct gendisk *disk;
 
-	spin_lock(&ubq->cancel_lock);
-	if (ubq->canceling) {
-		spin_unlock(&ubq->cancel_lock);
+	if (was_canceled)
 		return false;
-	}
-	ubq->canceling = true;
-	spin_unlock(&ubq->cancel_lock);
 
 	spin_lock(&ub->lock);
 	disk = ub->ub_disk;
@@ -1468,14 +1478,23 @@ static bool ublk_abort_requests(struct ublk_device *ub, struct ublk_queue *ubq)
 	if (!disk)
 		return false;
 
-	/* Now we are serialized with ublk_queue_rq() */
+	/*
+	 * Now we are serialized with ublk_queue_rq()
+	 *
+	 * Make sure that ubq->canceling is set when queue is frozen,
+	 * because ublk_queue_rq() has to rely on this flag for avoiding to
+	 * touch completed uring_cmd
+	 */
 	blk_mq_quiesce_queue(disk->queue);
-	/* abort queue is for making forward progress */
-	ublk_abort_queue(ub, ubq);
+	was_canceled = ublk_mark_queue_canceling(ubq);
+	if (!was_canceled) {
+		/* abort queue is for making forward progress */
+		ublk_abort_queue(ub, ubq);
+	}
 	blk_mq_unquiesce_queue(disk->queue);
 	put_device(disk_to_dev(disk));
 
-	return true;
+	return !was_canceled;
 }
 
 static void ublk_cancel_cmd(struct ublk_queue *ubq, struct ublk_io *io,
-- 
2.47.0

[PATCH V2 02/11] ublk: comment on ubq->canceling handling in ublk_queue_rq()

[Ming Lei]

In ublk_queue_rq(), ubq->canceling has to be handled after ->fail_io and
->force_abort are dealt with, otherwise the request may not be failed
when deleting disk.

Add comment on this usage.

Signed-off-by: Ming Lei <ming.lei@redhat.com>
---
 drivers/block/ublk_drv.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/drivers/block/ublk_drv.c b/drivers/block/ublk_drv.c
index fbcb7c2ff851..5b0c885dc38f 100644
--- a/drivers/block/ublk_drv.c
+++ b/drivers/block/ublk_drv.c
@@ -1310,6 +1310,11 @@ static blk_status_t ublk_queue_rq(struct blk_mq_hw_ctx *hctx,
 	if (ublk_nosrv_should_queue_io(ubq) && unlikely(ubq->force_abort))
 		return BLK_STS_IOERR;
 
+	/*
+	 * ->canceling has to be handled after ->force_abort and ->fail_io
+	 * is dealt with, otherwise this request may not be failed in case
+	 * of recovery, and cause hang when deleting disk
+	 */
 	if (unlikely(ubq->canceling)) {
 		__ublk_abort_rq(ubq, rq);
 		return BLK_STS_OK;
-- 
2.47.0

[PATCH V2 03/11] ublk: remove two unused fields from 'struct ublk_queue'

[Ming Lei]

Remove two unused fields(`io_addr` & `max_io_sz`) from `struct ublk_queue`.

Reviewed-by: Caleb Sander Mateos <csander@purestorage.com>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
---
 drivers/block/ublk_drv.c | 2 --
 1 file changed, 2 deletions(-)

diff --git a/drivers/block/ublk_drv.c b/drivers/block/ublk_drv.c
index 5b0c885dc38f..b60f4bd647a1 100644
--- a/drivers/block/ublk_drv.c
+++ b/drivers/block/ublk_drv.c
@@ -143,8 +143,6 @@ struct ublk_queue {
 	struct task_struct	*ubq_daemon;
 	char *io_cmd_buf;
 
-	unsigned long io_addr;	/* mapped vm address */
-	unsigned int max_io_sz;
 	bool force_abort;
 	bool timeout;
 	bool canceling;
-- 
2.47.0

[PATCH V2 04/11] ublk: add helper of ublk_need_map_io()

[Ming Lei]

ublk_need_map_io() is more readable.

Reviewed-by: Caleb Sander Mateos <csander@purestorage.com>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
---
 drivers/block/ublk_drv.c | 13 +++++++++----
 1 file changed, 9 insertions(+), 4 deletions(-)

diff --git a/drivers/block/ublk_drv.c b/drivers/block/ublk_drv.c
index b60f4bd647a1..200504dd67a9 100644
--- a/drivers/block/ublk_drv.c
+++ b/drivers/block/ublk_drv.c
@@ -596,6 +596,11 @@ static inline bool ublk_support_user_copy(const struct ublk_queue *ubq)
 	return ubq->flags & (UBLK_F_USER_COPY | UBLK_F_SUPPORT_ZERO_COPY);
 }
 
+static inline bool ublk_need_map_io(const struct ublk_queue *ubq)
+{
+	return !ublk_support_user_copy(ubq);
+}
+
 static inline bool ublk_need_req_ref(const struct ublk_queue *ubq)
 {
 	/*
@@ -923,7 +928,7 @@ static int ublk_map_io(const struct ublk_queue *ubq, const struct request *req,
 {
 	const unsigned int rq_bytes = blk_rq_bytes(req);
 
-	if (ublk_support_user_copy(ubq))
+	if (!ublk_need_map_io(ubq))
 		return rq_bytes;
 
 	/*
@@ -947,7 +952,7 @@ static int ublk_unmap_io(const struct ublk_queue *ubq,
 {
 	const unsigned int rq_bytes = blk_rq_bytes(req);
 
-	if (ublk_support_user_copy(ubq))
+	if (!ublk_need_map_io(ubq))
 		return rq_bytes;
 
 	if (ublk_need_unmap_req(req)) {
@@ -1867,7 +1872,7 @@ static int __ublk_ch_uring_cmd(struct io_uring_cmd *cmd,
 		if (io->flags & UBLK_IO_FLAG_OWNED_BY_SRV)
 			goto out;
 
-		if (!ublk_support_user_copy(ubq)) {
+		if (ublk_need_map_io(ubq)) {
 			/*
 			 * FETCH_RQ has to provide IO buffer if NEED GET
 			 * DATA is not enabled
@@ -1889,7 +1894,7 @@ static int __ublk_ch_uring_cmd(struct io_uring_cmd *cmd,
 		if (!(io->flags & UBLK_IO_FLAG_OWNED_BY_SRV))
 			goto out;
 
-		if (!ublk_support_user_copy(ubq)) {
+		if (ublk_need_map_io(ubq)) {
 			/*
 			 * COMMIT_AND_FETCH_REQ has to provide IO buffer if
 			 * NEED GET DATA is not enabled or it is Read IO.
-- 
2.47.0

[PATCH V2 05/11] ublk: call io_uring_cmd_to_pdu to get uring_cmd pdu

[Ming Lei]

Call io_uring_cmd_to_pdu() to get uring_cmd pdu, and one big benefit
is the automatic pdu size build check.

Suggested-by: Uday Shankar <ushankar@purestorage.com>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
---
 drivers/block/ublk_drv.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/block/ublk_drv.c b/drivers/block/ublk_drv.c
index 200504dd67a9..1e11816d0b90 100644
--- a/drivers/block/ublk_drv.c
+++ b/drivers/block/ublk_drv.c
@@ -1040,7 +1040,7 @@ static blk_status_t ublk_setup_iod(struct ublk_queue *ubq, struct request *req)
 static inline struct ublk_uring_cmd_pdu *ublk_get_uring_cmd_pdu(
 		struct io_uring_cmd *ioucmd)
 {
-	return (struct ublk_uring_cmd_pdu *)&ioucmd->pdu;
+	return io_uring_cmd_to_pdu(ioucmd, struct ublk_uring_cmd_pdu);
 }
 
 static inline bool ubq_daemon_is_dying(struct ublk_queue *ubq)
-- 
2.47.0

[PATCH V2 06/11] ublk: add segment parameter

[Ming Lei]

IO split is usually bad in io_uring world, since -EAGAIN is caused and
IO handling may have to fallback to io-wq, this way does hurt performance.

ublk starts to support zero copy recently, for avoiding unnecessary IO
split, ublk driver's segment limit should be aligned with backend
device's segment limit.

Another reason is that io_buffer_register_bvec() needs to allocate bvecs,
which number is aligned with ublk request segment number, so that big
memory allocation can be avoided by setting reasonable max_segments limit.

So add segment parameter for providing ublk server chance to align
segment limit with backend, and keep it reasonable from implementation
viewpoint.

Signed-off-by: Ming Lei <ming.lei@redhat.com>
---
 drivers/block/ublk_drv.c      | 20 +++++++++++++++++++-
 include/uapi/linux/ublk_cmd.h | 25 +++++++++++++++++++++++++
 2 files changed, 44 insertions(+), 1 deletion(-)

diff --git a/drivers/block/ublk_drv.c b/drivers/block/ublk_drv.c
index 1e11816d0b90..a5bcf3aa9d8c 100644
--- a/drivers/block/ublk_drv.c
+++ b/drivers/block/ublk_drv.c
@@ -74,7 +74,7 @@
 #define UBLK_PARAM_TYPE_ALL                                \
 	(UBLK_PARAM_TYPE_BASIC | UBLK_PARAM_TYPE_DISCARD | \
 	 UBLK_PARAM_TYPE_DEVT | UBLK_PARAM_TYPE_ZONED |    \
-	 UBLK_PARAM_TYPE_DMA_ALIGN)
+	 UBLK_PARAM_TYPE_DMA_ALIGN | UBLK_PARAM_TYPE_SEGMENT)
 
 struct ublk_rq_data {
 	struct kref ref;
@@ -580,6 +580,18 @@ static int ublk_validate_params(const struct ublk_device *ub)
 			return -EINVAL;
 	}
 
+	if (ub->params.types & UBLK_PARAM_TYPE_SEGMENT) {
+		const struct ublk_param_segment *p = &ub->params.seg;
+
+		if (!is_power_of_2(p->seg_boundary_mask + 1))
+			return -EINVAL;
+
+		if (p->seg_boundary_mask + 1 < UBLK_MIN_SEGMENT_SIZE)
+			return -EINVAL;
+		if (p->max_segment_size < UBLK_MIN_SEGMENT_SIZE)
+			return -EINVAL;
+	}
+
 	return 0;
 }
 
@@ -2370,6 +2382,12 @@ static int ublk_ctrl_start_dev(struct ublk_device *ub, struct io_uring_cmd *cmd)
 	if (ub->params.types & UBLK_PARAM_TYPE_DMA_ALIGN)
 		lim.dma_alignment = ub->params.dma.alignment;
 
+	if (ub->params.types & UBLK_PARAM_TYPE_SEGMENT) {
+		lim.seg_boundary_mask = ub->params.seg.seg_boundary_mask;
+		lim.max_segment_size = ub->params.seg.max_segment_size;
+		lim.max_segments = ub->params.seg.max_segments;
+	}
+
 	if (wait_for_completion_interruptible(&ub->completion) != 0)
 		return -EINTR;
 
diff --git a/include/uapi/linux/ublk_cmd.h b/include/uapi/linux/ublk_cmd.h
index 7255b36b5cf6..583b86681c93 100644
--- a/include/uapi/linux/ublk_cmd.h
+++ b/include/uapi/linux/ublk_cmd.h
@@ -410,6 +410,29 @@ struct ublk_param_dma_align {
 	__u8	pad[4];
 };
 
+#define UBLK_MIN_SEGMENT_SIZE   4096
+/*
+ * If any one of the three segment parameter is set as 0, the behavior is
+ * undefined.
+ */
+struct ublk_param_segment {
+	/*
+	 * seg_boundary_mask + 1 needs to be power_of_2(), and the sum has
+	 * to be >= UBLK_MIN_SEGMENT_SIZE(4096)
+	 */
+	__u64 	seg_boundary_mask;
+
+	/*
+	 * max_segment_size could be override by virt_boundary_mask, so be
+	 * careful when setting both.
+	 *
+	 * max_segment_size has to be >= UBLK_MIN_SEGMENT_SIZE(4096)
+	 */
+	__u32 	max_segment_size;
+	__u16 	max_segments;
+	__u8	pad[2];
+};
+
 struct ublk_params {
 	/*
 	 * Total length of parameters, userspace has to set 'len' for both
@@ -423,6 +446,7 @@ struct ublk_params {
 #define UBLK_PARAM_TYPE_DEVT            (1 << 2)
 #define UBLK_PARAM_TYPE_ZONED           (1 << 3)
 #define UBLK_PARAM_TYPE_DMA_ALIGN       (1 << 4)
+#define UBLK_PARAM_TYPE_SEGMENT         (1 << 5)
 	__u32	types;			/* types of parameter included */
 
 	struct ublk_param_basic		basic;
@@ -430,6 +454,7 @@ struct ublk_params {
 	struct ublk_param_devt		devt;
 	struct ublk_param_zoned	zoned;
 	struct ublk_param_dma_align	dma;
+	struct ublk_param_segment	seg;
 };
 
 #endif
-- 
2.47.0

[PATCH V2 07/11] ublk: document zero copy feature

[Ming Lei]

Add words to explain how zero copy feature works, and why it has to be
trusted for handling IO read command.

Signed-off-by: Ming Lei <ming.lei@redhat.com>
---
 Documentation/block/ublk.rst | 35 ++++++++++++++++++++++++++---------
 1 file changed, 26 insertions(+), 9 deletions(-)

diff --git a/Documentation/block/ublk.rst b/Documentation/block/ublk.rst
index 1e0e7358e14a..74c57488dc9a 100644
--- a/Documentation/block/ublk.rst
+++ b/Documentation/block/ublk.rst
@@ -309,18 +309,35 @@ with specified IO tag in the command data:
   ``UBLK_IO_COMMIT_AND_FETCH_REQ`` to the server, ublkdrv needs to copy
   the server buffer (pages) read to the IO request pages.
 
-Future development
-==================
-
 Zero copy
 ---------
 
-Zero copy is a generic requirement for nbd, fuse or similar drivers. A
-problem [#xiaoguang]_ Xiaoguang mentioned is that pages mapped to userspace
-can't be remapped any more in kernel with existing mm interfaces. This can
-occurs when destining direct IO to ``/dev/ublkb*``. Also, he reported that
-big requests (IO size >= 256 KB) may benefit a lot from zero copy.
-
+ublk zero copy relies on io_uring's fixed kernel buffer, which provides
+two APIs: `io_buffer_register_bvec()` and `io_buffer_unregister_bvec`.
+
+ublk adds IO command of `UBLK_IO_REGISTER_IO_BUF` to call
+`io_buffer_register_bvec()` for ublk server to register client request
+buffer into io_uring buffer table, then ublk server can submit io_uring
+IOs with the registered buffer index. IO command of `UBLK_IO_UNREGISTER_IO_BUF`
+calls `io_buffer_unregister_bvec()` to unregister the buffer, which is
+guaranteed to be live between calling `io_buffer_register_bvec()` and
+`io_buffer_unregister_bvec()`. Any io_uring operation which supports this
+kind of kernel buffer will grab one reference of the buffer until the
+operation is completed.
+
+ublk server implementing zero copy or user copy has to be CAP_SYS_ADMIN and
+be trusted, because it is ublk server's responsibility to make sure IO buffer
+filled with data for handling read command, and ublk server has to return
+correct result to ublk driver when handling READ command, and the result
+has to match with how many bytes filled to the IO buffer. Otherwise,
+uninitialized kernel IO buffer will be exposed to client application.
+
+ublk server needs to align the parameter of `struct ublk_param_dma_align`
+with backend for zero copy to work correctly.
+
+For reaching best IO performance, ublk server should align its segment
+parameter of `struct ublk_param_segment` with backend for avoiding
+unnecessary IO split, which usually hurts io_uring performance.
 
 References
 ==========
-- 
2.47.0

[PATCH V2 08/11] ublk: implement ->queue_rqs()

[Ming Lei]

Implement ->queue_rqs() for improving perf in case of MQ.

In this way, we just need to call io_uring_cmd_complete_in_task() once for
whole IO batch, then both io_uring and ublk server can get exact batch from
ublk frontend.

Follows IOPS improvement:

- tests

	tools/testing/selftests/ublk/kublk add -t null -q 2 [-z]

	fio/t/io_uring -p0 /dev/ublkb0

- results:

	more than 10% IOPS boost observed

Pass all ublk selftests, especially the io dispatch order test.

Cc: Uday Shankar <ushankar@purestorage.com>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
---
 drivers/block/ublk_drv.c | 131 +++++++++++++++++++++++++++++++++------
 1 file changed, 111 insertions(+), 20 deletions(-)

diff --git a/drivers/block/ublk_drv.c b/drivers/block/ublk_drv.c
index a5bcf3aa9d8c..f97919460515 100644
--- a/drivers/block/ublk_drv.c
+++ b/drivers/block/ublk_drv.c
@@ -81,6 +81,20 @@ struct ublk_rq_data {
 };
 
 struct ublk_uring_cmd_pdu {
+	/*
+	 * Store requests in same batch temporarily for queuing them to
+	 * daemon context.
+	 *
+	 * It should have been stored to request payload, but we do want
+	 * to avoid extra pre-allocation, and uring_cmd payload is always
+	 * free for us
+	 */
+	struct request *req_list;
+
+	/*
+	 * The following two are valid in this cmd whole lifetime, and
+	 * setup in ublk uring_cmd handler
+	 */
 	struct ublk_queue *ubq;
 	u16 tag;
 };
@@ -1170,14 +1184,12 @@ static inline void __ublk_abort_rq(struct ublk_queue *ubq,
 		blk_mq_end_request(rq, BLK_STS_IOERR);
 }
 
-static void ublk_rq_task_work_cb(struct io_uring_cmd *cmd,
-				 unsigned int issue_flags)
+static void ublk_dispatch_req(struct ublk_queue *ubq,
+			      struct io_uring_cmd *cmd,
+			      struct request *req,
+			      unsigned int issue_flags)
 {
-	struct ublk_uring_cmd_pdu *pdu = ublk_get_uring_cmd_pdu(cmd);
-	struct ublk_queue *ubq = pdu->ubq;
-	int tag = pdu->tag;
-	struct request *req = blk_mq_tag_to_rq(
-		ubq->dev->tag_set.tags[ubq->q_id], tag);
+	int tag = req->tag;
 	struct ublk_io *io = &ubq->ios[tag];
 	unsigned int mapped_bytes;
 
@@ -1252,6 +1264,18 @@ static void ublk_rq_task_work_cb(struct io_uring_cmd *cmd,
 	ubq_complete_io_cmd(io, UBLK_IO_RES_OK, issue_flags);
 }
 
+static void ublk_rq_task_work_cb(struct io_uring_cmd *cmd,
+				 unsigned int issue_flags)
+{
+	struct ublk_uring_cmd_pdu *pdu = ublk_get_uring_cmd_pdu(cmd);
+	struct ublk_queue *ubq = pdu->ubq;
+	int tag = pdu->tag;
+	struct request *req = blk_mq_tag_to_rq(
+		ubq->dev->tag_set.tags[ubq->q_id], tag);
+
+	ublk_dispatch_req(ubq, cmd, req, issue_flags);
+}
+
 static void ublk_queue_cmd(struct ublk_queue *ubq, struct request *rq)
 {
 	struct ublk_io *io = &ubq->ios[rq->tag];
@@ -1259,6 +1283,35 @@ static void ublk_queue_cmd(struct ublk_queue *ubq, struct request *rq)
 	io_uring_cmd_complete_in_task(io->cmd, ublk_rq_task_work_cb);
 }
 
+static void ublk_cmd_list_tw_cb(struct io_uring_cmd *cmd,
+		unsigned int issue_flags)
+{
+	struct ublk_uring_cmd_pdu *pdu = ublk_get_uring_cmd_pdu(cmd);
+	struct request *rq = pdu->req_list;
+	struct ublk_queue *ubq = rq->mq_hctx->driver_data;
+	struct request *next;
+
+	while (rq) {
+		struct ublk_io *io = &ubq->ios[rq->tag];
+
+		next = rq->rq_next;
+		rq->rq_next = NULL;
+		ublk_dispatch_req(ubq, io->cmd, rq, issue_flags);
+		rq = next;
+	}
+}
+
+static void ublk_queue_cmd_list(struct ublk_queue *ubq, struct rq_list *l)
+{
+	struct request *rq = rq_list_peek(l);
+	struct ublk_io *io = &ubq->ios[rq->tag];
+	struct ublk_uring_cmd_pdu *pdu = ublk_get_uring_cmd_pdu(io->cmd);
+
+	pdu->req_list = rq;
+	rq_list_init(l);
+	io_uring_cmd_complete_in_task(io->cmd, ublk_cmd_list_tw_cb);
+}
+
 static enum blk_eh_timer_return ublk_timeout(struct request *rq)
 {
 	struct ublk_queue *ubq = rq->mq_hctx->driver_data;
@@ -1297,21 +1350,12 @@ static enum blk_eh_timer_return ublk_timeout(struct request *rq)
 	return BLK_EH_RESET_TIMER;
 }
 
-static blk_status_t ublk_queue_rq(struct blk_mq_hw_ctx *hctx,
-		const struct blk_mq_queue_data *bd)
+static blk_status_t ublk_prep_req(struct ublk_queue *ubq, struct request *rq)
 {
-	struct ublk_queue *ubq = hctx->driver_data;
-	struct request *rq = bd->rq;
 	blk_status_t res;
 
-	if (unlikely(ubq->fail_io)) {
+	if (unlikely(ubq->fail_io))
 		return BLK_STS_TARGET;
-	}
-
-	/* fill iod to slot in io cmd buffer */
-	res = ublk_setup_iod(ubq, rq);
-	if (unlikely(res != BLK_STS_OK))
-		return BLK_STS_IOERR;
 
 	/* With recovery feature enabled, force_abort is set in
 	 * ublk_stop_dev() before calling del_gendisk(). We have to
@@ -1325,6 +1369,29 @@ static blk_status_t ublk_queue_rq(struct blk_mq_hw_ctx *hctx,
 	if (ublk_nosrv_should_queue_io(ubq) && unlikely(ubq->force_abort))
 		return BLK_STS_IOERR;
 
+	if (unlikely(ubq->canceling))
+		return BLK_STS_IOERR;
+
+	/* fill iod to slot in io cmd buffer */
+	res = ublk_setup_iod(ubq, rq);
+	if (unlikely(res != BLK_STS_OK))
+		return BLK_STS_IOERR;
+
+	blk_mq_start_request(rq);
+	return BLK_STS_OK;
+}
+
+static blk_status_t ublk_queue_rq(struct blk_mq_hw_ctx *hctx,
+		const struct blk_mq_queue_data *bd)
+{
+	struct ublk_queue *ubq = hctx->driver_data;
+	struct request *rq = bd->rq;
+	blk_status_t res;
+
+	res = ublk_prep_req(ubq, rq);
+	if (res != BLK_STS_OK)
+		return res;
+
 	/*
 	 * ->canceling has to be handled after ->force_abort and ->fail_io
 	 * is dealt with, otherwise this request may not be failed in case
@@ -1335,12 +1402,35 @@ static blk_status_t ublk_queue_rq(struct blk_mq_hw_ctx *hctx,
 		return BLK_STS_OK;
 	}
 
-	blk_mq_start_request(bd->rq);
 	ublk_queue_cmd(ubq, rq);
-
 	return BLK_STS_OK;
 }
 
+static void ublk_queue_rqs(struct rq_list *rqlist)
+{
+	struct rq_list requeue_list = { };
+	struct rq_list submit_list = { };
+	struct ublk_queue *ubq = NULL;
+	struct request *req;
+
+	while ((req = rq_list_pop(rqlist))) {
+		struct ublk_queue *this_q = req->mq_hctx->driver_data;
+
+		if (ubq && ubq != this_q && !rq_list_empty(&submit_list))
+			ublk_queue_cmd_list(ubq, &submit_list);
+		ubq = this_q;
+
+		if (ublk_prep_req(ubq, req) == BLK_STS_OK)
+			rq_list_add_tail(&submit_list, req);
+		else
+			rq_list_add_tail(&requeue_list, req);
+	}
+
+	if (ubq && !rq_list_empty(&submit_list))
+		ublk_queue_cmd_list(ubq, &submit_list);
+	*rqlist = requeue_list;
+}
+
 static int ublk_init_hctx(struct blk_mq_hw_ctx *hctx, void *driver_data,
 		unsigned int hctx_idx)
 {
@@ -1353,6 +1443,7 @@ static int ublk_init_hctx(struct blk_mq_hw_ctx *hctx, void *driver_data,
 
 static const struct blk_mq_ops ublk_mq_ops = {
 	.queue_rq       = ublk_queue_rq,
+	.queue_rqs      = ublk_queue_rqs,
 	.init_hctx	= ublk_init_hctx,
 	.timeout	= ublk_timeout,
 };
-- 
2.47.0

[PATCH V2 09/11] ublk: rename ublk_rq_task_work_cb as ublk_cmd_tw_cb

[Ming Lei]

The new name is aligned with ublk_cmd_list_tw_cb(), and looks
more readable.

Signed-off-by: Ming Lei <ming.lei@redhat.com>
---
 drivers/block/ublk_drv.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/drivers/block/ublk_drv.c b/drivers/block/ublk_drv.c
index f97919460515..355a59c78539 100644
--- a/drivers/block/ublk_drv.c
+++ b/drivers/block/ublk_drv.c
@@ -1264,8 +1264,8 @@ static void ublk_dispatch_req(struct ublk_queue *ubq,
 	ubq_complete_io_cmd(io, UBLK_IO_RES_OK, issue_flags);
 }
 
-static void ublk_rq_task_work_cb(struct io_uring_cmd *cmd,
-				 unsigned int issue_flags)
+static void ublk_cmd_tw_cb(struct io_uring_cmd *cmd,
+			   unsigned int issue_flags)
 {
 	struct ublk_uring_cmd_pdu *pdu = ublk_get_uring_cmd_pdu(cmd);
 	struct ublk_queue *ubq = pdu->ubq;
@@ -1280,7 +1280,7 @@ static void ublk_queue_cmd(struct ublk_queue *ubq, struct request *rq)
 {
 	struct ublk_io *io = &ubq->ios[rq->tag];
 
-	io_uring_cmd_complete_in_task(io->cmd, ublk_rq_task_work_cb);
+	io_uring_cmd_complete_in_task(io->cmd, ublk_cmd_tw_cb);
 }
 
 static void ublk_cmd_list_tw_cb(struct io_uring_cmd *cmd,
-- 
2.47.0

[PATCH V2 10/11] selftests: ublk: add more tests for covering MQ

[Ming Lei]

Add test test_generic_02.sh for covering IO dispatch order in case of MQ.

Especially we just support ->queue_rqs() which may affect IO dispatch
order.

Add test_loop_05.sh and test_stripe_03.sh for covering MQ.

Signed-off-by: Ming Lei <ming.lei@redhat.com>
---
 tools/testing/selftests/ublk/Makefile         |  3 ++
 tools/testing/selftests/ublk/test_common.sh   |  6 +++
 .../testing/selftests/ublk/test_generic_02.sh | 44 +++++++++++++++++++
 tools/testing/selftests/ublk/test_loop_01.sh  | 14 +++---
 tools/testing/selftests/ublk/test_loop_03.sh  | 14 +++---
 tools/testing/selftests/ublk/test_loop_05.sh  | 28 ++++++++++++
 .../testing/selftests/ublk/test_stress_01.sh  |  6 +--
 .../testing/selftests/ublk/test_stress_02.sh  |  6 +--
 .../testing/selftests/ublk/test_stripe_01.sh  | 14 +++---
 .../testing/selftests/ublk/test_stripe_03.sh  | 30 +++++++++++++
 10 files changed, 132 insertions(+), 33 deletions(-)
 create mode 100755 tools/testing/selftests/ublk/test_generic_02.sh
 create mode 100755 tools/testing/selftests/ublk/test_loop_05.sh
 create mode 100755 tools/testing/selftests/ublk/test_stripe_03.sh

diff --git a/tools/testing/selftests/ublk/Makefile b/tools/testing/selftests/ublk/Makefile
index 7817afe29005..7a8c994de244 100644
--- a/tools/testing/selftests/ublk/Makefile
+++ b/tools/testing/selftests/ublk/Makefile
@@ -4,6 +4,7 @@ CFLAGS += -O3 -Wl,-no-as-needed -Wall -I $(top_srcdir)
 LDLIBS += -lpthread -lm -luring
 
 TEST_PROGS := test_generic_01.sh
+TEST_PROGS += test_generic_02.sh
 
 TEST_PROGS += test_null_01.sh
 TEST_PROGS += test_null_02.sh
@@ -11,8 +12,10 @@ TEST_PROGS += test_loop_01.sh
 TEST_PROGS += test_loop_02.sh
 TEST_PROGS += test_loop_03.sh
 TEST_PROGS += test_loop_04.sh
+TEST_PROGS += test_loop_05.sh
 TEST_PROGS += test_stripe_01.sh
 TEST_PROGS += test_stripe_02.sh
+TEST_PROGS += test_stripe_03.sh
 
 TEST_PROGS += test_stress_01.sh
 TEST_PROGS += test_stress_02.sh
diff --git a/tools/testing/selftests/ublk/test_common.sh b/tools/testing/selftests/ublk/test_common.sh
index 75f54ac6b1c4..a88b35943227 100755
--- a/tools/testing/selftests/ublk/test_common.sh
+++ b/tools/testing/selftests/ublk/test_common.sh
@@ -23,6 +23,12 @@ _get_disk_dev_t() {
 	echo $(( (major & 0xfff) << 20 | (minor & 0xfffff) ))
 }
 
+_run_fio_verify_io() {
+	fio --name=verify --rw=randwrite --direct=1 --ioengine=libaio \
+		--bs=8k --iodepth=32 --verify=crc32c --do_verify=1 \
+		--verify_state_save=0 "$@" > /dev/null
+}
+
 _create_backfile() {
 	local my_size=$1
 	local my_file
diff --git a/tools/testing/selftests/ublk/test_generic_02.sh b/tools/testing/selftests/ublk/test_generic_02.sh
new file mode 100755
index 000000000000..3e80121e3bf5
--- /dev/null
+++ b/tools/testing/selftests/ublk/test_generic_02.sh
@@ -0,0 +1,44 @@
+#!/bin/bash
+# SPDX-License-Identifier: GPL-2.0
+
+. "$(cd "$(dirname "$0")" && pwd)"/test_common.sh
+
+TID="generic_02"
+ERR_CODE=0
+
+if ! _have_program bpftrace; then
+	exit "$UBLK_SKIP_CODE"
+fi
+
+_prep_test "null" "sequential io order for MQ"
+
+dev_id=$(_add_ublk_dev -t null -q 2)
+_check_add_dev $TID $?
+
+dev_t=$(_get_disk_dev_t "$dev_id")
+bpftrace trace/seq_io.bt "$dev_t" "W" 1 > "$UBLK_TMP" 2>&1 &
+btrace_pid=$!
+sleep 2
+
+if ! kill -0 "$btrace_pid" > /dev/null 2>&1; then
+	_cleanup_test "null"
+	exit "$UBLK_SKIP_CODE"
+fi
+
+# run fio over this ublk disk
+fio --name=write_seq \
+    --filename=/dev/ublkb"${dev_id}" \
+    --ioengine=libaio --iodepth=16 \
+    --rw=write \
+    --size=512M \
+    --direct=1 \
+    --bs=4k > /dev/null 2>&1
+ERR_CODE=$?
+kill "$btrace_pid"
+wait
+if grep -q "io_out_of_order" "$UBLK_TMP"; then
+	cat "$UBLK_TMP"
+	ERR_CODE=255
+fi
+_cleanup_test "null"
+_show_result $TID $ERR_CODE
diff --git a/tools/testing/selftests/ublk/test_loop_01.sh b/tools/testing/selftests/ublk/test_loop_01.sh
index c882d2a08e13..1ef8b6044777 100755
--- a/tools/testing/selftests/ublk/test_loop_01.sh
+++ b/tools/testing/selftests/ublk/test_loop_01.sh
@@ -6,6 +6,10 @@
 TID="loop_01"
 ERR_CODE=0
 
+if ! _have_program fio; then
+	exit "$UBLK_SKIP_CODE"
+fi
+
 _prep_test "loop" "write and verify test"
 
 backfile_0=$(_create_backfile 256M)
@@ -14,15 +18,7 @@ dev_id=$(_add_ublk_dev -t loop "$backfile_0")
 _check_add_dev $TID $? "${backfile_0}"
 
 # run fio over the ublk disk
-fio --name=write_and_verify \
-    --filename=/dev/ublkb"${dev_id}" \
-    --ioengine=libaio --iodepth=16 \
-    --rw=write \
-    --size=256M \
-    --direct=1 \
-    --verify=crc32c \
-    --do_verify=1 \
-    --bs=4k > /dev/null 2>&1
+_run_fio_verify_io --filename=/dev/ublkb"${dev_id}" --size=256M
 ERR_CODE=$?
 
 _cleanup_test "loop"
diff --git a/tools/testing/selftests/ublk/test_loop_03.sh b/tools/testing/selftests/ublk/test_loop_03.sh
index 269c96787d7d..e9ca744de8b1 100755
--- a/tools/testing/selftests/ublk/test_loop_03.sh
+++ b/tools/testing/selftests/ublk/test_loop_03.sh
@@ -6,6 +6,10 @@
 TID="loop_03"
 ERR_CODE=0
 
+if ! _have_program fio; then
+	exit "$UBLK_SKIP_CODE"
+fi
+
 _prep_test "loop" "write and verify over zero copy"
 
 backfile_0=$(_create_backfile 256M)
@@ -13,15 +17,7 @@ dev_id=$(_add_ublk_dev -t loop -z "$backfile_0")
 _check_add_dev $TID $? "$backfile_0"
 
 # run fio over the ublk disk
-fio --name=write_and_verify \
-    --filename=/dev/ublkb"${dev_id}" \
-    --ioengine=libaio --iodepth=64 \
-    --rw=write \
-    --size=256M \
-    --direct=1 \
-    --verify=crc32c \
-    --do_verify=1 \
-    --bs=4k > /dev/null 2>&1
+_run_fio_verify_io --filename=/dev/ublkb"${dev_id}" --size=256M
 ERR_CODE=$?
 
 _cleanup_test "loop"
diff --git a/tools/testing/selftests/ublk/test_loop_05.sh b/tools/testing/selftests/ublk/test_loop_05.sh
new file mode 100755
index 000000000000..2e6e2e6978fc
--- /dev/null
+++ b/tools/testing/selftests/ublk/test_loop_05.sh
@@ -0,0 +1,28 @@
+#!/bin/bash
+# SPDX-License-Identifier: GPL-2.0
+
+. "$(cd "$(dirname "$0")" && pwd)"/test_common.sh
+
+TID="loop_05"
+ERR_CODE=0
+
+if ! _have_program fio; then
+	exit "$UBLK_SKIP_CODE"
+fi
+
+_prep_test "loop" "write and verify test"
+
+backfile_0=$(_create_backfile 256M)
+
+dev_id=$(_add_ublk_dev -q 2 -t loop "$backfile_0")
+_check_add_dev $TID $? "${backfile_0}"
+
+# run fio over the ublk disk
+_run_fio_verify_io --filename=/dev/ublkb"${dev_id}" --size=256M
+ERR_CODE=$?
+
+_cleanup_test "loop"
+
+_remove_backfile "$backfile_0"
+
+_show_result $TID $ERR_CODE
diff --git a/tools/testing/selftests/ublk/test_stress_01.sh b/tools/testing/selftests/ublk/test_stress_01.sh
index 7177f6c57bc5..a8be24532b24 100755
--- a/tools/testing/selftests/ublk/test_stress_01.sh
+++ b/tools/testing/selftests/ublk/test_stress_01.sh
@@ -27,20 +27,20 @@ ublk_io_and_remove()
 
 _prep_test "stress" "run IO and remove device"
 
-ublk_io_and_remove 8G -t null
+ublk_io_and_remove 8G -t null -q 4
 ERR_CODE=$?
 if [ ${ERR_CODE} -ne 0 ]; then
 	_show_result $TID $ERR_CODE
 fi
 
 BACK_FILE=$(_create_backfile 256M)
-ublk_io_and_remove 256M -t loop "${BACK_FILE}"
+ublk_io_and_remove 256M -t loop -q 4 "${BACK_FILE}"
 ERR_CODE=$?
 if [ ${ERR_CODE} -ne 0 ]; then
 	_show_result $TID $ERR_CODE
 fi
 
-ublk_io_and_remove 256M -t loop -z "${BACK_FILE}"
+ublk_io_and_remove 256M -t loop -q 4 -z "${BACK_FILE}"
 ERR_CODE=$?
 _cleanup_test "stress"
 _remove_backfile "${BACK_FILE}"
diff --git a/tools/testing/selftests/ublk/test_stress_02.sh b/tools/testing/selftests/ublk/test_stress_02.sh
index 2a8e60579a06..2159e4cc8140 100755
--- a/tools/testing/selftests/ublk/test_stress_02.sh
+++ b/tools/testing/selftests/ublk/test_stress_02.sh
@@ -27,20 +27,20 @@ ublk_io_and_kill_daemon()
 
 _prep_test "stress" "run IO and kill ublk server"
 
-ublk_io_and_kill_daemon 8G -t null
+ublk_io_and_kill_daemon 8G -t null -q 4
 ERR_CODE=$?
 if [ ${ERR_CODE} -ne 0 ]; then
 	_show_result $TID $ERR_CODE
 fi
 
 BACK_FILE=$(_create_backfile 256M)
-ublk_io_and_kill_daemon 256M -t loop "${BACK_FILE}"
+ublk_io_and_kill_daemon 256M -t loop -q 4 "${BACK_FILE}"
 ERR_CODE=$?
 if [ ${ERR_CODE} -ne 0 ]; then
 	_show_result $TID $ERR_CODE
 fi
 
-ublk_io_and_kill_daemon 256M -t loop -z "${BACK_FILE}"
+ublk_io_and_kill_daemon 256M -t loop -q 4 -z "${BACK_FILE}"
 ERR_CODE=$?
 _cleanup_test "stress"
 _remove_backfile "${BACK_FILE}"
diff --git a/tools/testing/selftests/ublk/test_stripe_01.sh b/tools/testing/selftests/ublk/test_stripe_01.sh
index c01f3dc325ab..7e387ef656ea 100755
--- a/tools/testing/selftests/ublk/test_stripe_01.sh
+++ b/tools/testing/selftests/ublk/test_stripe_01.sh
@@ -6,6 +6,10 @@
 TID="stripe_01"
 ERR_CODE=0
 
+if ! _have_program fio; then
+	exit "$UBLK_SKIP_CODE"
+fi
+
 _prep_test "stripe" "write and verify test"
 
 backfile_0=$(_create_backfile 256M)
@@ -15,15 +19,7 @@ dev_id=$(_add_ublk_dev -t stripe "$backfile_0" "$backfile_1")
 _check_add_dev $TID $? "${backfile_0}"
 
 # run fio over the ublk disk
-fio --name=write_and_verify \
-    --filename=/dev/ublkb"${dev_id}" \
-    --ioengine=libaio --iodepth=32 \
-    --rw=write \
-    --size=512M \
-    --direct=1 \
-    --verify=crc32c \
-    --do_verify=1 \
-    --bs=4k > /dev/null 2>&1
+_run_fio_verify_io --filename=/dev/ublkb"${dev_id}" --size=512M
 ERR_CODE=$?
 
 _cleanup_test "stripe"
diff --git a/tools/testing/selftests/ublk/test_stripe_03.sh b/tools/testing/selftests/ublk/test_stripe_03.sh
new file mode 100755
index 000000000000..c1b34af36145
--- /dev/null
+++ b/tools/testing/selftests/ublk/test_stripe_03.sh
@@ -0,0 +1,30 @@
+#!/bin/bash
+# SPDX-License-Identifier: GPL-2.0
+
+. "$(cd "$(dirname "$0")" && pwd)"/test_common.sh
+
+TID="stripe_03"
+ERR_CODE=0
+
+if ! _have_program fio; then
+	exit "$UBLK_SKIP_CODE"
+fi
+
+_prep_test "stripe" "write and verify test"
+
+backfile_0=$(_create_backfile 256M)
+backfile_1=$(_create_backfile 256M)
+
+dev_id=$(_add_ublk_dev -q 2 -t stripe "$backfile_0" "$backfile_1")
+_check_add_dev $TID $? "${backfile_0}"
+
+# run fio over the ublk disk
+_run_fio_verify_io --filename=/dev/ublkb"${dev_id}" --size=512M
+ERR_CODE=$?
+
+_cleanup_test "stripe"
+
+_remove_backfile "$backfile_0"
+_remove_backfile "$backfile_1"
+
+_show_result $TID $ERR_CODE
-- 
2.47.0

[PATCH V2 11/11] selftests: ublk: add test for checking zero copy related parameter

[Ming Lei]

ublk zero copy usually requires to set dma and segment parameter correctly,
so hard-code null target's dma & segment parameter in non-default value,
and verify if they are setup correctly by ublk driver.

Signed-off-by: Ming Lei <ming.lei@redhat.com>
---
 tools/testing/selftests/ublk/Makefile         |  1 +
 tools/testing/selftests/ublk/null.c           | 11 +++++++-
 .../testing/selftests/ublk/test_generic_03.sh | 28 +++++++++++++++++++
 3 files changed, 39 insertions(+), 1 deletion(-)
 create mode 100755 tools/testing/selftests/ublk/test_generic_03.sh

diff --git a/tools/testing/selftests/ublk/Makefile b/tools/testing/selftests/ublk/Makefile
index 7a8c994de244..d98680d64a2f 100644
--- a/tools/testing/selftests/ublk/Makefile
+++ b/tools/testing/selftests/ublk/Makefile
@@ -5,6 +5,7 @@ LDLIBS += -lpthread -lm -luring
 
 TEST_PROGS := test_generic_01.sh
 TEST_PROGS += test_generic_02.sh
+TEST_PROGS += test_generic_03.sh
 
 TEST_PROGS += test_null_01.sh
 TEST_PROGS += test_null_02.sh
diff --git a/tools/testing/selftests/ublk/null.c b/tools/testing/selftests/ublk/null.c
index 899875ff50fe..91fec3690d4b 100644
--- a/tools/testing/selftests/ublk/null.c
+++ b/tools/testing/selftests/ublk/null.c
@@ -17,7 +17,8 @@ static int ublk_null_tgt_init(const struct dev_ctx *ctx, struct ublk_dev *dev)
 
 	dev->tgt.dev_size = dev_size;
 	dev->tgt.params = (struct ublk_params) {
-		.types = UBLK_PARAM_TYPE_BASIC,
+		.types = UBLK_PARAM_TYPE_BASIC | UBLK_PARAM_TYPE_DMA_ALIGN |
+			UBLK_PARAM_TYPE_SEGMENT,
 		.basic = {
 			.logical_bs_shift	= 9,
 			.physical_bs_shift	= 12,
@@ -26,6 +27,14 @@ static int ublk_null_tgt_init(const struct dev_ctx *ctx, struct ublk_dev *dev)
 			.max_sectors		= info->max_io_buf_bytes >> 9,
 			.dev_sectors		= dev_size >> 9,
 		},
+		.dma = {
+			.alignment 		= 4095,
+		},
+		.seg = {
+			.seg_boundary_mask 	= 4095,
+			.max_segment_size 	= 32 << 10,
+			.max_segments 		= 32,
+		},
 	};
 
 	if (info->flags & UBLK_F_SUPPORT_ZERO_COPY)
diff --git a/tools/testing/selftests/ublk/test_generic_03.sh b/tools/testing/selftests/ublk/test_generic_03.sh
new file mode 100755
index 000000000000..b551aa76cb0d
--- /dev/null
+++ b/tools/testing/selftests/ublk/test_generic_03.sh
@@ -0,0 +1,28 @@
+#!/bin/bash
+# SPDX-License-Identifier: GPL-2.0
+
+. "$(cd "$(dirname "$0")" && pwd)"/test_common.sh
+
+TID="generic_03"
+ERR_CODE=0
+
+_prep_test "null" "check dma & segment limits for zero copy"
+
+dev_id=$(_add_ublk_dev -t null -z)
+_check_add_dev $TID $?
+
+sysfs_path=/sys/block/ublkb"${dev_id}"
+dma_align=$(cat "$sysfs_path"/queue/dma_alignment)
+max_segments=$(cat "$sysfs_path"/queue/max_segments)
+max_segment_size=$(cat "$sysfs_path"/queue/max_segment_size)
+if [ "$dma_align" != "4095" ]; then
+	ERR_CODE=255
+fi
+if [ "$max_segments" != "32" ]; then
+	ERR_CODE=255
+fi
+if [ "$max_segment_size" != "32768" ]; then
+	ERR_CODE=255
+fi
+_cleanup_test "null"
+_show_result $TID $ERR_CODE
-- 
2.47.0

Re: [PATCH V2 05/11] ublk: call io_uring_cmd_to_pdu to get uring_cmd pdu

[Caleb Sander Mateos]

On Thu, Mar 27, 2025 at 2:52 AM Ming Lei <ming.lei@redhat.com> wrote:
>
> Call io_uring_cmd_to_pdu() to get uring_cmd pdu, and one big benefit
> is the automatic pdu size build check.
>
> Suggested-by: Uday Shankar <ushankar@purestorage.com>
> Signed-off-by: Ming Lei <ming.lei@redhat.com>

Reviewed-by: Caleb Sander Mateos <csander@purestorage.com>

Re: [PATCH V2 00/11] ublk: cleanup & improvement & zc follow-up

[Jens Axboe]

On Thu, 27 Mar 2025 17:51:09 +0800, Ming Lei wrote:
> The 1st two fixes ublk_abort_requests(), and adds comment on handling
> ubq->canceling.
> 
> The 3rd ~ 5th patches are cleanup.
> 
> The 6th and 7th are zc-followup.
> 
> [...]

Applied, thanks!

[01/11] ublk: make sure ubq->canceling is set when queue is frozen
        commit: 9c397ab202da574da65be6f4901d6260ad28d420
[02/11] ublk: comment on ubq->canceling handling in ublk_queue_rq()
        commit: 2563451efc04e6e32b089696d221498277b5addb
[03/11] ublk: remove two unused fields from 'struct ublk_queue'
        commit: b4ce4eae5c0e3afcdf4a1fb8c85e5c171a2ea5db
[04/11] ublk: add helper of ublk_need_map_io()
        commit: 8a799a1616dd34724d9283ca0c4b96003da53d6a
[05/11] ublk: call io_uring_cmd_to_pdu to get uring_cmd pdu
        commit: 639cf001d7cca2bdaccff3f545d80394b6b36a53
[06/11] ublk: add segment parameter
        commit: e14e391fc9cc38a54f7528077930eae4f573b58e
[07/11] ublk: document zero copy feature
        commit: 9f7862ebfb05db6ce88f6eeb0e6144cda284cdc2
[08/11] ublk: implement ->queue_rqs()
        commit: d7aad08075f13bd9eb9cc73df831278f6c843aa4
[09/11] ublk: rename ublk_rq_task_work_cb as ublk_cmd_tw_cb
        commit: 48c74741b43f77e7fef74f2ad2bb714bdf1675e1
[10/11] selftests: ublk: add more tests for covering MQ
        commit: 7e1121b53e27978c5e33f241e87f4ffee45febd9
[11/11] selftests: ublk: add test for checking zero copy related parameter
        commit: 888ba37f212022926462d7d0b993ee5354a30907

Best regards,
-- 
Jens Axboe