[PATCHv2 for-next 00/24] Misc update for rnbd

[PATCHv2 for-next 00/24] Misc update for rnbd

[Gioh Kim]

This is the misc update for rnbd. It inlcudes:
- Change maintainer
- Change domain address of maintainers' email: from cloud.ionos.com to ionos.com
- Add polling IO mode and document update
- Add some fault-injection points and document update
- Fix memory leak and some bug detected by static code analysis tools
- Code refactoring

V2->V1
- Change the title: for-rc -> for-next
- Remove unnecessary (void) casting requested by Leon

Best regards

Danil Kipnis (1):
  MAINTAINERS: Change maintainer for rnbd module

Dima Stepanov (2):
  block/rnbd-clt-sysfs: Remove copy buffer overlap in
    rnbd_clt_get_path_name
  block/rnbd: Use strscpy instead of strlcpy

Gioh Kim (13):
  Documentation/sysfs-block-rnbd: Add descriptions for remap_device and
    resize
  block/rnbd: Enable the fault-injection
  block/rnbd-srv: Inject a fault at bio processing
  block/rnbd-clt: Inject some fault points
  docs: fault-injection: Add fault-injection manual of RNBD
  docs: Add RTRS/RNBD to the index of fault-injection
  block/rnbd-clt: Replace {NO_WAIT,WAIT} with RTRS_PERMIT_{WAIT,NOWAIT}
  block/rnbd-srv: Prevent a deadlock generated by accessing sysfs in
    parallel
  block/rnbd-srv: Remove force_close file after holding a lock
  block/rnbd-clt: Fix missing a memory free when unloading the module
  block/rnbd-clt: Support polling mode for IO latency optimization
  Documentation/ABI/rnbd-clt: Add description for nr_poll_queues
  block/rnbd-srv: Remove unused arguments of rnbd_srv_rdma_ev

Guoqing Jiang (5):
  block/rnbd-clt: Remove some arguments from
    insert_dev_if_not_exists_devpath
  block/rnbd-clt: Remove some arguments from rnbd_client_setup_device
  block/rnbd-clt: Move add_disk(dev->gd) to rnbd_clt_setup_gen_disk
  block/rnbd: Kill rnbd_clt_destroy_default_group
  block/rnbd: Kill destroy_device_cb

Jack Wang (1):
  block/rnbd-clt: Remove max_segment_size

Md Haris Iqbal (1):
  block/rnbd-clt: Generate kobject_uevent when the rnbd device state
    changes

Tom Rix (1):
  block/rnbd-clt: Improve find_or_create_sess() return check

 Documentation/ABI/testing/sysfs-block-rnbd    |  18 ++
 .../ABI/testing/sysfs-class-rnbd-client       |  13 ++
 Documentation/fault-injection/index.rst       |   2 +
 .../fault-injection/rnbd-fault-injection.rst  | 208 ++++++++++++++++++
 MAINTAINERS                                   |   4 +-
 drivers/block/rnbd/rnbd-clt-sysfs.c           | 138 +++++++++---
 drivers/block/rnbd/rnbd-clt.c                 | 184 +++++++++++-----
 drivers/block/rnbd/rnbd-clt.h                 |  21 +-
 drivers/block/rnbd/rnbd-common.c              |  44 ++++
 drivers/block/rnbd/rnbd-proto.h               |  14 ++
 drivers/block/rnbd/rnbd-srv-sysfs.c           |  41 +++-
 drivers/block/rnbd/rnbd-srv.c                 |  76 +++----
 drivers/block/rnbd/rnbd-srv.h                 |  16 +-
 drivers/infiniband/ulp/rtrs/rtrs-clt.c        |  75 +++++--
 drivers/infiniband/ulp/rtrs/rtrs-clt.h        |   1 -
 drivers/infiniband/ulp/rtrs/rtrs-pri.h        |   1 +
 drivers/infiniband/ulp/rtrs/rtrs-srv.c        |   4 +-
 drivers/infiniband/ulp/rtrs/rtrs.h            |  13 +-
 18 files changed, 712 insertions(+), 161 deletions(-)
 create mode 100644 Documentation/fault-injection/rnbd-fault-injection.rst

-- 
2.25.1

[PATCHv2 for-next 01/24] MAINTAINERS: Change maintainer for rnbd module

[Gioh Kim]

From: Danil Kipnis <danil.kipnis@cloud.ionos.com>

Danil steps down, Haris will take over.
Also update email address to ionos.com, the old
cloud.ionos.com will still work for some time.

Signed-off-by: Danil Kipnis <danil.kipnis@cloud.ionos.com>
Acked-by: Md Haris Iqbal <haris.iqbal@cloud.ionos.com>
Signed-off-by: Jack Wang <jinpu.wang@cloud.ionos.com>
---
 MAINTAINERS | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/MAINTAINERS b/MAINTAINERS
index bf947775390c..723ba354dce6 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -15358,8 +15358,8 @@ N:	riscv
 K:	riscv
 
 RNBD BLOCK DRIVERS
-M:	Danil Kipnis <danil.kipnis@cloud.ionos.com>
-M:	Jack Wang <jinpu.wang@cloud.ionos.com>
+M:	Md. Haris Iqbal <haris.iqbal@ionos.com>
+M:	Jack Wang <jinpu.wang@ionos.com>
 L:	linux-block@vger.kernel.org
 S:	Maintained
 F:	drivers/block/rnbd/
-- 
2.25.1

[PATCHv2 for-next 02/24] Documentation/sysfs-block-rnbd: Add descriptions for remap_device and resize

[Gioh Kim]

From: Gioh Kim <gi-oh.kim@cloud.ionos.com>

Two sysfs entries, remap_device and resize, are missing.

Signed-off-by: Gioh Kim <gi-oh.kim@cloud.ionos.com>
Signed-off-by: Jack Wang <jinpu.wang@cloud.ionos.com>
---
 Documentation/ABI/testing/sysfs-block-rnbd | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/Documentation/ABI/testing/sysfs-block-rnbd b/Documentation/ABI/testing/sysfs-block-rnbd
index 14a6fe9422b3..ec716e1c31a8 100644
--- a/Documentation/ABI/testing/sysfs-block-rnbd
+++ b/Documentation/ABI/testing/sysfs-block-rnbd
@@ -44,3 +44,15 @@ Date:		Feb 2020
 KernelVersion:	5.7
 Contact:	Jack Wang <jinpu.wang@cloud.ionos.com> Danil Kipnis <danil.kipnis@cloud.ionos.com>
 Description:	Contains the device access mode: ro, rw or migration.
+
+What:		/sys/block/rnbd<N>/rnbd/resize
+Date:		Feb 2020
+KernelVersion:	5.7
+Contact:	Jack Wang <jinpu.wang@cloud.ionos.com> Danil Kipnis <danil.kipnis@cloud.ionos.com>
+Description:	Write the number of sectors to change the size of the disk.
+
+What:		/sys/block/rnbd<N>/rnbd/remap_device
+Date:		Feb 2020
+KernelVersion:	5.7
+Contact:	Jack Wang <jinpu.wang@cloud.ionos.com> Danil Kipnis <danil.kipnis@cloud.ionos.com>
+Description:	Remap the disconnected device if the session is not destroyed yet.
-- 
2.25.1

[PATCHv2 for-next 03/24] block/rnbd: Enable the fault-injection

[Gioh Kim]

From: Gioh Kim <gi-oh.kim@cloud.ionos.com>

This patch introduces functions to enable the fault-injection for RTRS.
* rnbd_fault_inject_init/final: initialize the fault-injection
and create a debugfs directory.
* rnbd_fault_inject_add: create a debugfs entry to enable
the fault-injection point.

Signed-off-by: Gioh Kim <gi-oh.kim@cloud.ionos.com>
Signed-off-by: Jack Wang <jinpu.wang@cloud.ionos.com>
---
 drivers/block/rnbd/rnbd-common.c | 44 ++++++++++++++++++++++++++++++++
 drivers/block/rnbd/rnbd-proto.h  | 14 ++++++++++
 2 files changed, 58 insertions(+)

diff --git a/drivers/block/rnbd/rnbd-common.c b/drivers/block/rnbd/rnbd-common.c
index 596c3f732403..84bfbf015f6d 100644
--- a/drivers/block/rnbd/rnbd-common.c
+++ b/drivers/block/rnbd/rnbd-common.c
@@ -21,3 +21,47 @@ const char *rnbd_access_mode_str(enum rnbd_access_mode mode)
 		return "unknown";
 	}
 }
+
+#ifdef CONFIG_FAULT_INJECTION_DEBUG_FS
+static DECLARE_FAULT_ATTR(fail_default_attr);
+
+void rnbd_fault_inject_init(struct rnbd_fault_inject *fj,
+			    const char *dir_name,
+			    u32 err_status)
+{
+	struct dentry *dir, *parent;
+	struct fault_attr *attr = &fj->attr;
+
+	/* create debugfs directory and attribute */
+	parent = debugfs_create_dir(dir_name, NULL);
+	if (!parent) {
+		pr_warn("%s: failed to create debugfs directory\n", dir_name);
+		return;
+	}
+
+	*attr = fail_default_attr;
+	dir = fault_create_debugfs_attr("fault_inject", parent, attr);
+	if (IS_ERR(dir)) {
+		pr_warn("%s: failed to create debugfs attr\n", dir_name);
+		debugfs_remove_recursive(parent);
+		return;
+	}
+	fj->parent = parent;
+	fj->dir = dir;
+
+	/* create debugfs for status code */
+	fj->status = err_status;
+	debugfs_create_u32("status", 0600, dir,	&fj->status);
+}
+
+void rnbd_fault_inject_add(struct dentry *dir, const char *fname, bool *value)
+{
+	debugfs_create_bool(fname, 0600, dir, value);
+}
+
+void rnbd_fault_inject_final(struct rnbd_fault_inject *fj)
+{
+	/* remove debugfs directories */
+	debugfs_remove_recursive(fj->parent);
+}
+#endif
diff --git a/drivers/block/rnbd/rnbd-proto.h b/drivers/block/rnbd/rnbd-proto.h
index c1bc5c0fef71..d13dc1d3a00e 100644
--- a/drivers/block/rnbd/rnbd-proto.h
+++ b/drivers/block/rnbd/rnbd-proto.h
@@ -15,6 +15,7 @@
 #include <linux/inet.h>
 #include <linux/in.h>
 #include <linux/in6.h>
+#include <linux/fault-inject.h>
 #include <rdma/ib.h>
 
 #define RNBD_PROTO_VER_MAJOR 2
@@ -305,6 +306,19 @@ static inline u32 rq_to_rnbd_flags(struct request *rq)
 	return rnbd_opf;
 }
 
+struct rnbd_fault_inject {
+#ifdef CONFIG_FAULT_INJECTION_DEBUG_FS
+	struct fault_attr attr;
+	struct dentry *parent;
+	struct dentry *dir;
+	u32 status;
+#endif
+};
+
 const char *rnbd_access_mode_str(enum rnbd_access_mode mode);
 
+void rnbd_fault_inject_init(struct rnbd_fault_inject *fj,
+			    const char *dev_name, u32 err_status);
+void rnbd_fault_inject_add(struct dentry *dir, const char *fname, bool *value);
+void rnbd_fault_inject_final(struct rnbd_fault_inject *fj);
 #endif /* RNBD_PROTO_H */
-- 
2.25.1

[PATCHv2 for-next 04/24] block/rnbd-srv: Inject a fault at bio processing

[Gioh Kim]

From: Gioh Kim <gi-oh.kim@cloud.ionos.com>

If the fault is enabled, it sends an error to the client
so that the client thinks the target device on the server has failed.

Signed-off-by: Gioh Kim <gi-oh.kim@cloud.ionos.com>
Signed-off-by: Jack Wang <jinpu.wang@cloud.ionos.com>
---
 drivers/block/rnbd/rnbd-srv-sysfs.c | 36 +++++++++++++++++++++++++++++
 drivers/block/rnbd/rnbd-srv.c       |  7 ++++++
 drivers/block/rnbd/rnbd-srv.h       | 13 +++++++++++
 3 files changed, 56 insertions(+)

diff --git a/drivers/block/rnbd/rnbd-srv-sysfs.c b/drivers/block/rnbd/rnbd-srv-sysfs.c
index 05ffe488ddc6..278a981302b9 100644
--- a/drivers/block/rnbd/rnbd-srv-sysfs.c
+++ b/drivers/block/rnbd/rnbd-srv-sysfs.c
@@ -253,3 +253,39 @@ void rnbd_srv_destroy_sysfs_files(void)
 	device_destroy(rnbd_dev_class, MKDEV(0, 0));
 	class_destroy(rnbd_dev_class);
 }
+
+#ifdef CONFIG_FAULT_INJECTION_DEBUG_FS
+void rnbd_srv_fault_inject_init(struct rnbd_srv_fault_inject *fault_inject,
+				const char *dev_name)
+{
+	rnbd_fault_inject_init(&fault_inject->fj, dev_name, -EBUSY);
+	/* injection points */
+	rnbd_fault_inject_add(fault_inject->fj.dir,
+			      "fail-bio", &fault_inject->fail_bio);
+}
+
+void rnbd_srv_fault_inject_fini(struct rnbd_srv_fault_inject *fault_inject)
+{
+	rnbd_fault_inject_final(&fault_inject->fj);
+}
+
+int rnbd_should_fail_bio(struct rnbd_srv_sess_dev *sess_dev)
+{
+	struct rnbd_srv_fault_inject *fault_inject = &sess_dev->fault_inject;
+	if (fault_inject->fail_bio && should_fail(&fault_inject->fj.attr, 1))
+		return fault_inject->fj.status;
+	return 0;
+}
+#else
+void rnbd_srv_fault_inject_init(struct rnbd_srv_fault_inject *fault_inj,
+				const char *dev_name)
+{
+}
+void rnbd_srv_fault_inject_fini(struct rnbd_srv_fault_inject *fault_inject)
+{
+}
+int rnbd_should_fail_bio(struct rnbd_srv_sess_dev *sess_dev)
+{
+	return 0;
+}
+#endif
diff --git a/drivers/block/rnbd/rnbd-srv.c b/drivers/block/rnbd/rnbd-srv.c
index a6a68d44f517..447fb0718525 100644
--- a/drivers/block/rnbd/rnbd-srv.c
+++ b/drivers/block/rnbd/rnbd-srv.c
@@ -88,9 +88,14 @@ void rnbd_endio(void *priv, int error)
 {
 	struct rnbd_io_private *rnbd_priv = priv;
 	struct rnbd_srv_sess_dev *sess_dev = rnbd_priv->sess_dev;
+	int fail_err = 0;
 
 	rnbd_put_sess_dev(sess_dev);
 
+	fail_err = rnbd_should_fail_bio(sess_dev);
+	if (unlikely(fail_err)) /* over-write error which will be sent to client */
+		error = fail_err;
+
 	rtrs_srv_resp_rdma(rnbd_priv->id, error);
 
 	kfree(priv);
@@ -230,6 +235,7 @@ void rnbd_destroy_sess_dev(struct rnbd_srv_sess_dev *sess_dev, bool keep_id)
 	rnbd_put_sess_dev(sess_dev);
 	wait_for_completion(&dc); /* wait for inflights to drop to zero */
 
+	rnbd_srv_fault_inject_fini(&sess_dev->fault_inject);
 	rnbd_dev_close(sess_dev->rnbd_dev);
 	list_del(&sess_dev->sess_list);
 	mutex_lock(&sess_dev->dev->lock);
@@ -811,6 +817,7 @@ static int process_msg_open(struct rtrs_srv *rtrs,
 	rnbd_srv_info(srv_sess_dev, "Opened device '%s'\n", srv_dev->id);
 
 	kfree(full_path);
+	rnbd_srv_fault_inject_init(&srv_sess_dev->fault_inject, kbasename(srv_sess_dev->pathname));
 
 fill_response:
 	rnbd_srv_fill_msg_open_rsp(rsp, srv_sess_dev);
diff --git a/drivers/block/rnbd/rnbd-srv.h b/drivers/block/rnbd/rnbd-srv.h
index b157371c25ed..120e6d64cb82 100644
--- a/drivers/block/rnbd/rnbd-srv.h
+++ b/drivers/block/rnbd/rnbd-srv.h
@@ -45,6 +45,13 @@ struct rnbd_srv_dev {
 	int				open_write_cnt;
 };
 
+struct rnbd_srv_fault_inject {
+#ifdef CONFIG_FAULT_INJECTION_DEBUG_FS
+	struct rnbd_fault_inject fj;
+	bool fail_bio;
+#endif
+};
+
 /* Structure which binds N devices and N sessions */
 struct rnbd_srv_sess_dev {
 	/* Entry inside rnbd_srv_dev struct */
@@ -62,6 +69,7 @@ struct rnbd_srv_sess_dev {
 	struct completion               *destroy_comp;
 	char				pathname[NAME_MAX];
 	enum rnbd_access_mode		access_mode;
+	struct rnbd_srv_fault_inject    fault_inject;
 };
 
 void rnbd_srv_sess_dev_force_close(struct rnbd_srv_sess_dev *sess_dev);
@@ -77,4 +85,9 @@ int rnbd_srv_create_sysfs_files(void);
 void rnbd_srv_destroy_sysfs_files(void);
 void rnbd_destroy_sess_dev(struct rnbd_srv_sess_dev *sess_dev, bool keep_id);
 
+void rnbd_srv_fault_inject_init(struct rnbd_srv_fault_inject *fault_inj,
+				const char *dev_name);
+void rnbd_srv_fault_inject_fini(struct rnbd_srv_fault_inject *fault_inject);
+int rnbd_should_fail_bio(struct rnbd_srv_sess_dev *sess_dev);
+
 #endif /* RNBD_SRV_H */
-- 
2.25.1

[PATCHv2 for-next 05/24] block/rnbd-clt: Inject some fault points

[Gioh Kim]

From: Gioh Kim <gi-oh.kim@cloud.ionos.com>

This patch injects two fault points:
1. generate an IO error
2. generate a unmap failure

Signed-off-by: Gioh Kim <gi-oh.kim@cloud.ionos.com>
Signed-off-by: Jack Wang <jinpu.wang@cloud.ionos.com>
---
 drivers/block/rnbd/rnbd-clt-sysfs.c | 53 +++++++++++++++++++++++++++++
 drivers/block/rnbd/rnbd-clt.c       | 17 +++++++++
 drivers/block/rnbd/rnbd-clt.h       | 15 ++++++++
 3 files changed, 85 insertions(+)

diff --git a/drivers/block/rnbd/rnbd-clt-sysfs.c b/drivers/block/rnbd/rnbd-clt-sysfs.c
index d4aa6bfc9555..d83415875960 100644
--- a/drivers/block/rnbd/rnbd-clt-sysfs.c
+++ b/drivers/block/rnbd/rnbd-clt-sysfs.c
@@ -651,3 +651,56 @@ void rnbd_clt_destroy_sysfs_files(void)
 	device_destroy(rnbd_dev_class, MKDEV(0, 0));
 	class_destroy(rnbd_dev_class);
 }
+
+#ifdef CONFIG_FAULT_INJECTION_DEBUG_FS
+void rnbd_clt_fault_inject_init(struct rnbd_clt_fault_inject *fault_inject,
+				const char *dev_name)
+{
+	rnbd_fault_inject_init(&fault_inject->fj, dev_name, -EBUSY);
+	/* injection points */
+	rnbd_fault_inject_add(fault_inject->fj.dir,
+			      "fail-request", &fault_inject->fail_request);
+	rnbd_fault_inject_add(fault_inject->fj.dir,
+			      "fail-unmap", &fault_inject->fail_unmap);
+}
+
+void rnbd_clt_fault_inject_final(struct rnbd_clt_fault_inject *fault_inject)
+{
+	rnbd_fault_inject_final(&fault_inject->fj);
+}
+
+int rnbd_clt_should_fail_request(struct request *req)
+{
+	struct rnbd_clt_dev *dev = req->rq_disk->private_data;
+	struct rnbd_clt_fault_inject *fault_inject = &dev->fault_inject;
+
+	if (fault_inject->fail_request && should_fail(&fault_inject->fj.attr, 1))
+		return fault_inject->fj.status;
+	return 0;
+}
+
+int rnbd_clt_should_fail_unmap(struct rnbd_clt_dev *dev)
+{
+	struct rnbd_clt_fault_inject *fault_inject = &dev->fault_inject;
+
+	if (fault_inject->fail_unmap && should_fail(&fault_inject->fj.attr, 1))
+		return fault_inject->fj.status;
+	return 0;
+}
+#else
+void rnbd_clt_fault_inject_init(struct rnbd_clt_fault_inject *fault_inj,
+				const char *dev_name)
+{
+}
+void rnbd_clt_fault_inject_final(struct rnbd_clt_fault_inject *fault_inject)
+{
+}
+int rnbd_clt_should_fail_request(struct request *req)
+{
+	return 0;
+}
+int rnbd_clt_should_fail_unmap(struct rnbd_clt_dev *dev)
+{
+	return 0;
+}
+#endif
diff --git a/drivers/block/rnbd/rnbd-clt.c b/drivers/block/rnbd/rnbd-clt.c
index 45a470076652..8c9a02c8b8bd 100644
--- a/drivers/block/rnbd/rnbd-clt.c
+++ b/drivers/block/rnbd/rnbd-clt.c
@@ -411,6 +411,11 @@ static void msg_io_conf(void *priv, int errno)
 	struct rnbd_clt_dev *dev = iu->dev;
 	struct request *rq = iu->rq;
 	int rw = rq_data_dir(rq);
+	int fail_err = 0;
+
+	fail_err = rnbd_clt_should_fail_request(rq);
+	if (unlikely(fail_err)) /* over-write error */
+		errno = fail_err;
 
 	iu->errno = errno;
 
@@ -1161,6 +1166,7 @@ static blk_status_t rnbd_queue_rq(struct blk_mq_hw_ctx *hctx,
 	}
 
 	blk_mq_start_request(rq);
+
 	err = rnbd_client_xfer_request(dev, rq, iu);
 	if (likely(err == 0))
 		return BLK_STS_OK;
@@ -1545,6 +1551,8 @@ struct rnbd_clt_dev *rnbd_clt_map_device(const char *sessname,
 		goto send_close;
 	}
 
+	rnbd_clt_fault_inject_init(&dev->fault_inject, dev->gd->disk_name);
+
 	rnbd_clt_info(dev,
 		       "map_device: Device mapped as %s (nsectors: %zu, logical_block_size: %d, physical_block_size: %d, max_write_same_sectors: %d, max_discard_sectors: %d, discard_granularity: %d, discard_alignment: %d, secure_discard: %d, max_segments: %d, max_hw_sectors: %d, rotational: %d, wc: %d, fua: %d)\n",
 		       dev->gd->disk_name, dev->nsectors,
@@ -1599,8 +1607,16 @@ int rnbd_clt_unmap_device(struct rnbd_clt_dev *dev, bool force,
 	struct rnbd_clt_session *sess = dev->sess;
 	int refcount, ret = 0;
 	bool was_mapped;
+	int fail_err = 0;
 
 	mutex_lock(&dev->lock);
+
+	fail_err = rnbd_clt_should_fail_unmap(dev);
+	if (unlikely(fail_err)) {
+		ret = fail_err;
+		goto err;
+	}
+
 	if (dev->dev_state == DEV_STATE_UNMAPPED) {
 		rnbd_clt_info(dev, "Device is already being unmapped\n");
 		ret = -EALREADY;
@@ -1618,6 +1634,7 @@ int rnbd_clt_unmap_device(struct rnbd_clt_dev *dev, bool force,
 	dev->dev_state = DEV_STATE_UNMAPPED;
 	mutex_unlock(&dev->lock);
 
+	rnbd_clt_fault_inject_final(&dev->fault_inject);
 	delete_dev(dev);
 	destroy_sysfs(dev, sysfs_self);
 	destroy_gen_disk(dev);
diff --git a/drivers/block/rnbd/rnbd-clt.h b/drivers/block/rnbd/rnbd-clt.h
index 537d499dad3b..5ecbe8dedf24 100644
--- a/drivers/block/rnbd/rnbd-clt.h
+++ b/drivers/block/rnbd/rnbd-clt.h
@@ -107,6 +107,14 @@ struct rnbd_queue {
 	struct blk_mq_hw_ctx	*hctx;
 };
 
+struct rnbd_clt_fault_inject {
+#ifdef CONFIG_FAULT_INJECTION_DEBUG_FS
+	struct rnbd_fault_inject fj;
+	bool fail_unmap;
+	bool fail_request;
+#endif
+};
+
 struct rnbd_clt_dev {
 	struct rnbd_clt_session	*sess;
 	struct request_queue	*queue;
@@ -139,6 +147,7 @@ struct rnbd_clt_dev {
 	char			*blk_symlink_name;
 	refcount_t		refcount;
 	struct work_struct	unmap_on_rmmod_work;
+	struct rnbd_clt_fault_inject fault_inject;
 };
 
 /* rnbd-clt.c */
@@ -163,4 +172,10 @@ void rnbd_clt_destroy_default_group(void);
 
 void rnbd_clt_remove_dev_symlink(struct rnbd_clt_dev *dev);
 
+void rnbd_clt_fault_inject_init(struct rnbd_clt_fault_inject *fault_inj,
+			    const char *dev_name);
+void rnbd_clt_fault_inject_final(struct rnbd_clt_fault_inject *fault_inject);
+int rnbd_clt_should_fail_request(struct request *req);
+int rnbd_clt_should_fail_unmap(struct rnbd_clt_dev *dev);
+int rnbd_clt_should_fail_request_timeout(struct request *req);
 #endif /* RNBD_CLT_H */
-- 
2.25.1

[PATCHv2 for-next 06/24] docs: fault-injection: Add fault-injection manual of RNBD

[Gioh Kim]

From: Gioh Kim <gi-oh.kim@cloud.ionos.com>

It describes how to use the fault-injection of RNBD.

Signed-off-by: Gioh Kim <gi-oh.kim@cloud.ionos.com>
---
 .../fault-injection/rnbd-fault-injection.rst  | 208 ++++++++++++++++++
 1 file changed, 208 insertions(+)
 create mode 100644 Documentation/fault-injection/rnbd-fault-injection.rst

diff --git a/Documentation/fault-injection/rnbd-fault-injection.rst b/Documentation/fault-injection/rnbd-fault-injection.rst
new file mode 100644
index 000000000000..21594e5e3c91
--- /dev/null
+++ b/Documentation/fault-injection/rnbd-fault-injection.rst
@@ -0,0 +1,208 @@
+RNBD (RDMA Network Block Device) Fault Injection
+================================================
+This document introduces how to enable and use the error injection of RNBD
+via debugfs in the /sys/kernel/debug directory. When enabled, users can
+enable specific error injection point and change the default status code
+via the debugfs.
+
+Following examples show how to inject an error into the RNBD.
+
+First, enable CONFIG_FAULT_INJECTION_DEBUG_FS kernel config,
+recompile the kernel. After booting up the kernel, map a target device.
+
+On client, /sys/kernel/debug/rnbdX directory is created after mapping.
+And /sys/kernel/debug/<mapped-device> directory is created on server.
+
+Example 1: Inject an error into request processing of rnbd-client
+-----------------------------------------------------------------
+
+::
+
+  echo 1 > /sys/kernel/debug/rnbd0/fault_inject/times
+  echo 100 > /sys/kernel/debug/rnbd0/fault_inject/probability
+  echo 1 > /sys/kernel/debug/rnbd0/fault_inject/fail-request
+  dd if=/dev/rnbd0 of=./dd bs=1k count=10
+
+Expected Result::
+
+  dd succeeds but generates an IO error
+
+Message from dmesg::
+
+  FAULT_INJECTION: forcing a failure.
+  name fault_inject, interval 1, probability 100, space 0, times 1
+  CPU: 4 PID: 0 Comm: swapper/4 Tainted: G           O      5.4.77-pserver+ #167
+  Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.13.0-1ubuntu1.1 04/01/2014
+  Call Trace:
+    <IRQ>
+    dump_stack+0x97/0xe0
+    should_fail.cold+0x5/0x11
+    rnbd_clt_should_fail_request+0x5e/0x80 [rnbd_client]
+    msg_io_conf+0x42/0xb0 [rnbd_client]
+    complete_rdma_req+0x264/0x600 [rtrs_client]
+    rtrs_clt_rdma_done+0x4a2/0x690 [rtrs_client]
+    __ib_process_cq+0x94/0x100 [ib_core]
+    ib_poll_handler+0x3f/0xa0 [ib_core]
+    irq_poll_softirq+0xf8/0x280
+    __do_softirq+0x122/0x550
+    irq_exit+0xfb/0x100
+    do_IRQ+0x8a/0x170
+    common_interrupt+0xf/0xf
+    </IRQ>
+  RIP: 0010:default_idle+0x2b/0x1d0
+  Code: 1f 44 00 00 41 55 41 54 65 44 8b 25 7f fe 0a 5a 55 53 0f 1f 44 00 00 e8 53 65 30 ff e9 07 00 00 00 0f 00 2d b7 59 4b 00 fb f4 <65> 44 8b 25 5d fe 0a 5a 0f 1f 44 00 00 5b 5d 41 5c 41 5d c3 65 8b
+  RSP: 0018:ffff88811963fdc8 EFLAGS: 00000246 ORIG_RAX: ffffffffffffffdd
+  RAX: 0000000000000000 RBX: ffff888119633240 RCX: dffffc0000000000
+  RDX: 0000000000000007 RSI: 0000000000000006 RDI: ffff888119633ad4
+  RBP: 0000000000000004 R08: ffffffffa516d49d R09: 0000000000000000
+  R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000004
+  R13: 0000000000000000 R14: ffff888119633240 R15: 0000000000000000
+    do_idle+0x314/0x370
+    cpu_startup_entry+0x19/0x20
+    start_secondary+0x212/0x280
+    secondary_startup_64+0xa4/0xb0
+  rnbd_client L432: </dev/nullb0@bla> read I/O failed with err: -16
+  blk_update_request: device resource error, dev rnbd0, sector 0 op 0x0:(READ) flags 0x80700 phys_seg 4 prio class 0
+
+Example 2: Inject an error into unmapping of rnbd-client
+--------------------------------------------------------
+
+::
+
+  echo 100 > /sys/kernel/debug/rnbd0/fault_inject/probability
+  echo 1 > /sys/kernel/debug/rnbd0/fault_inject/times
+  echo 1 > /sys/kernel/debug/rnbd0/fault_inject/fail-unmap
+  echo normal > /sys/block/rnbd0/rnbd/unmap_device
+
+Expected Result::
+
+  echo: write error: Device or resource busy
+
+Message from dmesg::
+
+  FAULT_INJECTION: forcing a failure.
+  name fault_inject, interval 1, probability 100, space 0, times 1
+  CPU: 2 PID: 648 Comm: bash Tainted: G           O      5.4.77-pserver+ #169
+  Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.13.0-1ubuntu1.1 04/01/2014
+  Call Trace:
+    dump_stack+0x97/0xe0
+    should_fail.cold+0x5/0x11
+    rnbd_clt_should_fail_unmap+0x38/0x60 [rnbd_client]
+    rnbd_clt_unmap_device+0x3c/0x1c0 [rnbd_client]
+    rnbd_clt_unmap_dev_store.cold+0xe5/0x13f [rnbd_client]
+    kernfs_fop_write+0x141/0x240
+    vfs_write+0xf2/0x250
+    ksys_write+0xc3/0x160
+    do_syscall_64+0x68/0x260
+    entry_SYSCALL_64_after_hwframe+0x49/0xbe
+  RIP: 0033:0x7ff883091504
+  Code: 00 f7 d8 64 89 02 48 c7 c0 ff ff ff ff eb b3 0f 1f 80 00 00 00 00 48 8d 05 f9 61 0d 00 8b 00 85 c0 75 13 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 54 c3 0f 1f 00 41 54 49 89 d4 55 48 89 f5 53
+  RSP: 002b:00007ffe1bc91458 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
+  RAX: ffffffffffffffda RBX: 0000000000000007 RCX: 00007ff883091504
+  RDX: 0000000000000007 RSI: 000056389b73a180 RDI: 0000000000000001
+  RBP: 000056389b73a180 R08: 000000000000000a R09: 00007ff883121e80
+  R10: 000000000000000a R11: 0000000000000246 R12: 00007ff883163760
+  R13: 0000000000000007 R14: 00007ff88315e760 R15: 0000000000000007
+  rnbd_client L335: </dev/nullb0@bla> unmap_device: -16
+  rnbd_client L321: </dev/nullb0@bla> Unmapping device, option: normal.
+
+Example 3: Inject an error into bio process of rnbd-server
+----------------------------------------------------------
+
+After client maps null0b, you can see /sys/kernel/debug/nullb0 directory on server::
+
+  echo 100 > /sys/kernel/debug/nullb0/fault_inject/probability
+  echo 1 > /sys/kernel/debug/nullb0/fault_inject/times
+  echo 1 > /sys/kernel/debug/nullb0/fault_inject/fail-bio
+
+Then you can generate IO on client::
+
+  dd if=/dev/rnbd0 of=./dd bs=1k count=10
+
+Expected Result on client::
+
+  dd succeeds but generates an IO error
+
+Message from dmesg on client::
+
+  rtrs_client L453: <bla>: IO request failed: error=-16 path=ip:192.168.122.142@ip:192.168.122.130 [mlx4_0:1] notify=1
+  rnbd_client L432: </dev/nullb0@bla> read I/O failed with err: -16
+  blk_update_request: device resource error, dev rnbd0, sector 0 op 0x0:(READ) flags 0x80700 phys_seg 4 prio class 0
+
+Message from dmesg on server::
+
+  FAULT_INJECTION: forcing a failure.
+  name fault_inject, interval 1, probability 100, space 0, times 1
+  CPU: 4 PID: 31 Comm: ksoftirqd/4 Tainted: G           O      5.4.77-pserver+ #169
+  Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.13.0-1ubuntu1.1 04/01/2014
+  Call Trace:
+    dump_stack+0x97/0xe0
+    should_fail.cold+0x5/0x11
+    rnbd_should_fail_bio+0x38/0x51 [rnbd_server]
+    rnbd_endio+0x41/0x70 [rnbd_server]
+    rnbd_dev_bi_end_io+0x43/0x50 [rnbd_server]
+    blk_update_request+0x1af/0x520
+    blk_mq_end_request+0x2e/0x200
+    blk_done_softirq+0x16e/0x1c0
+    __do_softirq+0x122/0x550
+    run_ksoftirqd+0x24/0x30
+    smpboot_thread_fn+0x1a2/0x2d0
+    kthread+0x191/0x1e0
+    ret_from_fork+0x3a/0x50
+
+Example 4: Change the status code
+---------------------------------
+
+The default status code is -16 (-EBUSY) but you can change it::
+
+  echo 1 > /sys/kernel/debug/rnbd0/fault_inject/times
+  echo 100 > /sys/kernel/debug/rnbd0/fault_inject/probability
+  echo 1 > /sys/kernel/debug/rnbd0/fault_inject/fail-request
+  echo -10 > /sys/kernel/debug/rnbd0/fault_inject/status
+  dd if=/dev/rnbd0 of=./dd bs=1k count=10
+
+Expected Result::
+
+  The error value is -10
+
+Message from dmesg::
+
+  FAULT_INJECTION: forcing a failure.
+  name fault_inject, interval 1, probability 100, space 0, times 1
+  CPU: 4 PID: 0 Comm: swapper/4 Tainted: G           O      5.4.77-pserver+ #170
+  Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.13.0-1ubuntu1.1 04/01/2014
+  Call Trace:
+  <IRQ>
+    dump_stack+0x97/0xe0
+    should_fail.cold+0x5/0x11
+    rnbd_clt_should_fail_request+0x5e/0x80 [rnbd_client]
+    msg_io_conf+0x42/0xb0 [rnbd_client]
+    complete_rdma_req+0x264/0x600 [rtrs_client]
+    rtrs_clt_rdma_done+0x4a2/0x690 [rtrs_client]
+    __ib_process_cq+0x94/0x100 [ib_core]
+    ib_poll_handler+0x3f/0xa0 [ib_core]
+    irq_poll_softirq+0xf8/0x280
+    __do_softirq+0x122/0x550
+    irq_exit+0xfb/0x100
+    do_IRQ+0x8a/0x170
+    common_interrupt+0xf/0xf
+    </IRQ>
+  RIP: 0010:default_idle+0x2b/0x1d0
+  Code: 1f 44 00 00 41 55 41 54 65 44 8b 25 7f fe 0a 7c 55 53 0f 1f 44 00 00 e8 53 65 30 ff e9 07 00 00 00 0f 00 2d b7 59 4b 00 fb f4 <65> 44 8b 25 5d fe 0a 7c 0f 1f 44 00 00 5b 5d 41 5c 41 5d c3 65 8b
+  RSP: 0018:ffff888114e2fdc8 EFLAGS: 00000246 ORIG_RAX: ffffffffffffffdd
+  RAX: 0000000000000000 RBX: ffff888114e26440 RCX: dffffc0000000000
+  RDX: 0000000000000007 RSI: 0000000000000006 RDI: ffff888114e26cd4
+  RBP: 0000000000000004 R08: ffffffff8316d49d R09: 0000000000000000
+  R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000004
+  R13: 0000000000000000 R14: ffff888114e26440 R15: 0000000000000000
+    ? lockdep_hardirqs_on+0x17d/0x250
+    ? default_idle+0x1d/0x1d0
+    do_idle+0x314/0x370
+    ? arch_cpu_idle_exit+0x40/0x40
+    ? schedule_idle+0x46/0x60
+    cpu_startup_entry+0x19/0x20
+    start_secondary+0x212/0x280
+    ? set_cpu_sibling_map+0xcb0/0xcb0
+    secondary_startup_64+0xa4/0xb0
+  rnbd_client L432: </dev/nullb0@bla> read I/O failed with err: -10
+  blk_update_request: I/O error, dev rnbd0, sector 0 op 0x0:(READ) flags 0x80700 phys_seg 3 prio class 0
-- 
2.25.1

[PATCHv2 for-next 07/24] docs: Add RTRS/RNBD to the index of fault-injection

[Gioh Kim]

From: Gioh Kim <gi-oh.kim@cloud.ionos.com>

Add new documents for RTRS and RNBD to the index file.

Signed-off-by: Gioh Kim <gi-oh.kim@cloud.ionos.com>
Signed-off-by: Jack Wang <jinpu.wang@cloud.ionos.com>
---
 Documentation/fault-injection/index.rst | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/Documentation/fault-injection/index.rst b/Documentation/fault-injection/index.rst
index 8408a8a91b34..669d146af874 100644
--- a/Documentation/fault-injection/index.rst
+++ b/Documentation/fault-injection/index.rst
@@ -11,6 +11,8 @@ fault-injection
     notifier-error-inject
     nvme-fault-injection
     provoke-crashes
+    rnbd-fault-injection
+    rtrs-fault-injection
 
 .. only::  subproject and html
 
-- 
2.25.1

[PATCHv2 for-next 08/24] block/rnbd-clt: Remove some arguments from insert_dev_if_not_exists_devpath

[Gioh Kim]

From: Guoqing Jiang <guoqing.jiang@gmx.com>

Remove 'pathname' and 'sess' since we can dereference it from 'dev'.

Signed-off-by: Guoqing Jiang <guoqing.jiang@gmx.com>
Reviewed-by: Danil Kipnis <danil.kipnis@cloud.ionos.com>
Signed-off-by: Gioh Kim <gi-oh.kim@cloud.ionos.com>
Signed-off-by: Jack Wang <jinpu.wang@cloud.ionos.com>
---
 drivers/block/rnbd/rnbd-clt.c | 9 ++++-----
 1 file changed, 4 insertions(+), 5 deletions(-)

diff --git a/drivers/block/rnbd/rnbd-clt.c b/drivers/block/rnbd/rnbd-clt.c
index 8c9a02c8b8bd..c8de016553a9 100644
--- a/drivers/block/rnbd/rnbd-clt.c
+++ b/drivers/block/rnbd/rnbd-clt.c
@@ -1477,14 +1477,13 @@ static bool exists_devpath(const char *pathname, const char *sessname)
 	return found;
 }
 
-static bool insert_dev_if_not_exists_devpath(const char *pathname,
-					     struct rnbd_clt_session *sess,
-					     struct rnbd_clt_dev *dev)
+static bool insert_dev_if_not_exists_devpath(struct rnbd_clt_dev *dev)
 {
 	bool found;
+	struct rnbd_clt_session *sess = dev->sess;
 
 	mutex_lock(&sess_lock);
-	found = __exists_dev(pathname, sess->sessname);
+	found = __exists_dev(dev->pathname, sess->sessname);
 	if (!found) {
 		mutex_lock(&sess->lock);
 		list_add_tail(&dev->list, &sess->devs_list);
@@ -1528,7 +1527,7 @@ struct rnbd_clt_dev *rnbd_clt_map_device(const char *sessname,
 		ret = PTR_ERR(dev);
 		goto put_sess;
 	}
-	if (insert_dev_if_not_exists_devpath(pathname, sess, dev)) {
+	if (insert_dev_if_not_exists_devpath(dev)) {
 		ret = -EEXIST;
 		goto put_dev;
 	}
-- 
2.25.1

Re: [PATCHv2 for-next 08/24] block/rnbd-clt: Remove some arguments from insert_dev_if_not_exists_devpath

[Chaitanya Kulkarni]

On 3/30/21 00:39, Gioh Kim wrote:
> From: Guoqing Jiang <guoqing.jiang@gmx.com>
>
> Remove 'pathname' and 'sess' since we can dereference it from 'dev'.
>
> Signed-off-by: Guoqing Jiang <guoqing.jiang@gmx.com>
> Reviewed-by: Danil Kipnis <danil.kipnis@cloud.ionos.com>
> Signed-off-by: Gioh Kim <gi-oh.kim@cloud.ionos.com>
> Signed-off-by: Jack Wang <jinpu.wang@cloud.ionos.com>

Looks good.

Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>

[PATCHv2 for-next 09/24] block/rnbd-clt: Remove some arguments from rnbd_client_setup_device

[Gioh Kim]

From: Guoqing Jiang <guoqing.jiang@gmx.com>

Remove them since both sess and idx can be dereferenced from dev. And
sess is not used in the function.

Signed-off-by: Guoqing Jiang <guoqing.jiang@gmx.com>
Reviewed-by: Danil Kipnis <danil.kipnis@cloud.ionos.com>
Signed-off-by: Gioh Kim <gi-oh.kim@cloud.ionos.com>
Signed-off-by: Jack Wang <jinpu.wang@cloud.ionos.com>
---
 drivers/block/rnbd/rnbd-clt.c | 7 +++----
 1 file changed, 3 insertions(+), 4 deletions(-)

diff --git a/drivers/block/rnbd/rnbd-clt.c b/drivers/block/rnbd/rnbd-clt.c
index c8de016553a9..5d085bc80e24 100644
--- a/drivers/block/rnbd/rnbd-clt.c
+++ b/drivers/block/rnbd/rnbd-clt.c
@@ -1360,10 +1360,9 @@ static void rnbd_clt_setup_gen_disk(struct rnbd_clt_dev *dev, int idx)
 		blk_queue_flag_set(QUEUE_FLAG_NONROT, dev->queue);
 }
 
-static int rnbd_client_setup_device(struct rnbd_clt_session *sess,
-				     struct rnbd_clt_dev *dev, int idx)
+static int rnbd_client_setup_device(struct rnbd_clt_dev *dev)
 {
-	int err;
+	int err, idx = dev->clt_device_id;
 
 	dev->size = dev->nsectors * dev->logical_block_size;
 
@@ -1541,7 +1540,7 @@ struct rnbd_clt_dev *rnbd_clt_map_device(const char *sessname,
 	mutex_lock(&dev->lock);
 	pr_debug("Opened remote device: session=%s, path='%s'\n",
 		 sess->sessname, pathname);
-	ret = rnbd_client_setup_device(sess, dev, dev->clt_device_id);
+	ret = rnbd_client_setup_device(dev);
 	if (ret) {
 		rnbd_clt_err(dev,
 			      "map_device: Failed to configure device, err: %d\n",
-- 
2.25.1

Re: [PATCHv2 for-next 09/24] block/rnbd-clt: Remove some arguments from rnbd_client_setup_device

[Chaitanya Kulkarni]

On 3/30/21 00:39, Gioh Kim wrote:
> From: Guoqing Jiang <guoqing.jiang@gmx.com>
>
> Remove them since both sess and idx can be dereferenced from dev. And
> sess is not used in the function.
>
> Signed-off-by: Guoqing Jiang <guoqing.jiang@gmx.com>
> Reviewed-by: Danil Kipnis <danil.kipnis@cloud.ionos.com>
> Signed-off-by: Gioh Kim <gi-oh.kim@cloud.ionos.com>
> Signed-off-by: Jack Wang <jinpu.wang@cloud.ionos.com>

Looks good.

Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>

[PATCHv2 for-next 10/24] block/rnbd-clt: Move add_disk(dev->gd) to rnbd_clt_setup_gen_disk

[Gioh Kim]

From: Guoqing Jiang <guoqing.jiang@gmx.com>

It makes more sense to add gendisk in rnbd_clt_setup_gen_disk, instead
of do it in rnbd_clt_map_device.

Signed-off-by: Guoqing Jiang <guoqing.jiang@gmx.com>
Reviewed-by: Danil Kipnis <danil.kipnis@cloud.ionos.com>
Signed-off-by: Gioh Kim <gi-oh.kim@cloud.ionos.com>
Signed-off-by: Jack Wang <jinpu.wang@cloud.ionos.com>
---
 drivers/block/rnbd/rnbd-clt.c | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/drivers/block/rnbd/rnbd-clt.c b/drivers/block/rnbd/rnbd-clt.c
index 5d085bc80e24..d8b9c552271c 100644
--- a/drivers/block/rnbd/rnbd-clt.c
+++ b/drivers/block/rnbd/rnbd-clt.c
@@ -1358,6 +1358,7 @@ static void rnbd_clt_setup_gen_disk(struct rnbd_clt_dev *dev, int idx)
 
 	if (!dev->rotational)
 		blk_queue_flag_set(QUEUE_FLAG_NONROT, dev->queue);
+	add_disk(dev->gd);
 }
 
 static int rnbd_client_setup_device(struct rnbd_clt_dev *dev)
@@ -1561,8 +1562,6 @@ struct rnbd_clt_dev *rnbd_clt_map_device(const char *sessname,
 		       dev->max_hw_sectors, dev->rotational, dev->wc, dev->fua);
 
 	mutex_unlock(&dev->lock);
-
-	add_disk(dev->gd);
 	rnbd_clt_put_sess(sess);
 
 	return dev;
-- 
2.25.1

Re: [PATCHv2 for-next 10/24] block/rnbd-clt: Move add_disk(dev->gd) to rnbd_clt_setup_gen_disk

[Chaitanya Kulkarni]

On 3/30/21 00:39, Gioh Kim wrote:
> From: Guoqing Jiang <guoqing.jiang@gmx.com>
>
> It makes more sense to add gendisk in rnbd_clt_setup_gen_disk, instead
> of do it in rnbd_clt_map_device.
>
> Signed-off-by: Guoqing Jiang <guoqing.jiang@gmx.com>
> Reviewed-by: Danil Kipnis <danil.kipnis@cloud.ionos.com>
> Signed-off-by: Gioh Kim <gi-oh.kim@cloud.ionos.com>
> Signed-off-by: Jack Wang <jinpu.wang@cloud.ionos.com>

The add disk call seems to be out of the lock, I hope that will not
result in any issues since this patch moves add_disk call when
dev->lock is held.

Looks good.

Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>

Re: [PATCHv2 for-next 10/24] block/rnbd-clt: Move add_disk(dev->gd) to rnbd_clt_setup_gen_disk

[Gioh Kim]

On Wed, Mar 31, 2021 at 1:55 AM Chaitanya Kulkarni
<Chaitanya.Kulkarni@wdc.com> wrote:
>
> On 3/30/21 00:39, Gioh Kim wrote:
> > From: Guoqing Jiang <guoqing.jiang@gmx.com>
> >
> > It makes more sense to add gendisk in rnbd_clt_setup_gen_disk, instead
> > of do it in rnbd_clt_map_device.
> >
> > Signed-off-by: Guoqing Jiang <guoqing.jiang@gmx.com>
> > Reviewed-by: Danil Kipnis <danil.kipnis@cloud.ionos.com>
> > Signed-off-by: Gioh Kim <gi-oh.kim@cloud.ionos.com>
> > Signed-off-by: Jack Wang <jinpu.wang@cloud.ionos.com>
>
> The add disk call seems to be out of the lock, I hope that will not
> result in any issues since this patch moves add_disk call when
> dev->lock is held.

I checked other modules and found that pktcdvd and mtd/ubi does add_disk
when holding mutex.
I hope so.

Thank you.

>
> Looks good.
>
> Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
>
>

[PATCHv2 for-next 11/24] block/rnbd: Kill rnbd_clt_destroy_default_group

[Gioh Kim]

From: Guoqing Jiang <guoqing.jiang@cloud.ionos.com>

No need to have it since we can call sysfs_remove_group in the
rnbd_clt_destroy_sysfs_files.

Then rnbd_clt_destroy_sysfs_files is paired with it's counterpart
rnbd_clt_create_sysfs_files.

Signed-off-by: Guoqing Jiang <guoqing.jiang@ionos.com>
Reviewed-by: Danil Kipnis <danil.kipnis@ionos.com>
Signed-off-by: Gioh Kim <gi-oh.kim@ionos.com>
Signed-off-by: Jack Wang <jinpu.wang@ionos.com>
---
 drivers/block/rnbd/rnbd-clt-sysfs.c | 6 +-----
 drivers/block/rnbd/rnbd-clt.c       | 1 -
 drivers/block/rnbd/rnbd-clt.h       | 1 -
 3 files changed, 1 insertion(+), 7 deletions(-)

diff --git a/drivers/block/rnbd/rnbd-clt-sysfs.c b/drivers/block/rnbd/rnbd-clt-sysfs.c
index d83415875960..2452eb67547c 100644
--- a/drivers/block/rnbd/rnbd-clt-sysfs.c
+++ b/drivers/block/rnbd/rnbd-clt-sysfs.c
@@ -639,13 +639,9 @@ int rnbd_clt_create_sysfs_files(void)
 	return err;
 }
 
-void rnbd_clt_destroy_default_group(void)
-{
-	sysfs_remove_group(&rnbd_dev->kobj, &default_attr_group);
-}
-
 void rnbd_clt_destroy_sysfs_files(void)
 {
+	sysfs_remove_group(&rnbd_dev->kobj, &default_attr_group);
 	kobject_del(rnbd_devs_kobj);
 	kobject_put(rnbd_devs_kobj);
 	device_destroy(rnbd_dev_class, MKDEV(0, 0));
diff --git a/drivers/block/rnbd/rnbd-clt.c b/drivers/block/rnbd/rnbd-clt.c
index d8b9c552271c..fce0f345f796 100644
--- a/drivers/block/rnbd/rnbd-clt.c
+++ b/drivers/block/rnbd/rnbd-clt.c
@@ -1692,7 +1692,6 @@ static void rnbd_destroy_sessions(void)
 	struct rnbd_clt_dev *dev, *tn;
 
 	/* Firstly forbid access through sysfs interface */
-	rnbd_clt_destroy_default_group();
 	rnbd_clt_destroy_sysfs_files();
 
 	/*
diff --git a/drivers/block/rnbd/rnbd-clt.h b/drivers/block/rnbd/rnbd-clt.h
index 5ecbe8dedf24..d2a709f5d7ed 100644
--- a/drivers/block/rnbd/rnbd-clt.h
+++ b/drivers/block/rnbd/rnbd-clt.h
@@ -168,7 +168,6 @@ int rnbd_clt_resize_disk(struct rnbd_clt_dev *dev, size_t newsize);
 int rnbd_clt_create_sysfs_files(void);
 
 void rnbd_clt_destroy_sysfs_files(void);
-void rnbd_clt_destroy_default_group(void);
 
 void rnbd_clt_remove_dev_symlink(struct rnbd_clt_dev *dev);
 
-- 
2.25.1

Re: [PATCHv2 for-next 11/24] block/rnbd: Kill rnbd_clt_destroy_default_group

[Chaitanya Kulkarni]

On 3/30/21 00:39, Gioh Kim wrote:
> From: Guoqing Jiang <guoqing.jiang@cloud.ionos.com>
>
> No need to have it since we can call sysfs_remove_group in the
> rnbd_clt_destroy_sysfs_files.
>
> Then rnbd_clt_destroy_sysfs_files is paired with it's counterpart
> rnbd_clt_create_sysfs_files.
>
> Signed-off-by: Guoqing Jiang <guoqing.jiang@ionos.com>
> Reviewed-by: Danil Kipnis <danil.kipnis@ionos.com>
> Signed-off-by: Gioh Kim <gi-oh.kim@ionos.com>
> Signed-off-by: Jack Wang <jinpu.wang@ionos.com>

Looks good.

Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>

[PATCHv2 for-next 12/24] block/rnbd: Kill destroy_device_cb

[Gioh Kim]

From: Guoqing Jiang <guoqing.jiang@cloud.ionos.com>

We can use destroy_device directly since destroy_device_cb is just the
wrapper of destroy_device.

Signed-off-by: Guoqing Jiang <guoqing.jiang@ionos.com>
Reviewed-by: Danil Kipnis <danil.kipnis@ionos.com>
Signed-off-by: Gioh Kim <gi-oh.kim@ionos.com>
Signed-off-by: Jack Wang <jinpu.wang@ionos.com>
---
 drivers/block/rnbd/rnbd-srv.c | 15 ++++-----------
 1 file changed, 4 insertions(+), 11 deletions(-)

diff --git a/drivers/block/rnbd/rnbd-srv.c b/drivers/block/rnbd/rnbd-srv.c
index 447fb0718525..895e9c313ff0 100644
--- a/drivers/block/rnbd/rnbd-srv.c
+++ b/drivers/block/rnbd/rnbd-srv.c
@@ -183,8 +183,10 @@ static int process_rdma(struct rtrs_srv *sess,
 	return err;
 }
 
-static void destroy_device(struct rnbd_srv_dev *dev)
+static void destroy_device(struct kref *kref)
 {
+	struct rnbd_srv_dev *dev = container_of(kref, struct rnbd_srv_dev, kref);
+
 	WARN_ONCE(!list_empty(&dev->sess_dev_list),
 		  "Device %s is being destroyed but still in use!\n",
 		  dev->id);
@@ -203,18 +205,9 @@ static void destroy_device(struct rnbd_srv_dev *dev)
 		kfree(dev);
 }
 
-static void destroy_device_cb(struct kref *kref)
-{
-	struct rnbd_srv_dev *dev;
-
-	dev = container_of(kref, struct rnbd_srv_dev, kref);
-
-	destroy_device(dev);
-}
-
 static void rnbd_put_srv_dev(struct rnbd_srv_dev *dev)
 {
-	kref_put(&dev->kref, destroy_device_cb);
+	kref_put(&dev->kref, destroy_device);
 }
 
 void rnbd_destroy_sess_dev(struct rnbd_srv_sess_dev *sess_dev, bool keep_id)
-- 
2.25.1

Re: [PATCHv2 for-next 12/24] block/rnbd: Kill destroy_device_cb

[Chaitanya Kulkarni]

On 3/30/21 00:39, Gioh Kim wrote:
> From: Guoqing Jiang <guoqing.jiang@cloud.ionos.com>
>
> We can use destroy_device directly since destroy_device_cb is just the
> wrapper of destroy_device.
>
> Signed-off-by: Guoqing Jiang <guoqing.jiang@ionos.com>
> Reviewed-by: Danil Kipnis <danil.kipnis@ionos.com>
> Signed-off-by: Gioh Kim <gi-oh.kim@ionos.com>
> Signed-off-by: Jack Wang <jinpu.wang@ionos.com>

Looks good.

Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>

[PATCHv2 for-next 13/24] block/rnbd-clt: Replace {NO_WAIT,WAIT} with RTRS_PERMIT_{WAIT,NOWAIT}

[Gioh Kim]

From: Gioh Kim <gi-oh.kim@cloud.ionos.com>

They are defined with the same value and similar meaning, let's remove
one of them, then we can remove {WAIT,NOWAIT}.

Also change the type of 'wait' from 'int' to 'enum wait_type' to make
it clear.

Cc: Jason Gunthorpe <jgg@mellanox.com>
Cc: Leon Romanovsky <leonro@nvidia.com>
Cc: linux-rdma@vger.kernel.org
Signed-off-by: Guoqing Jiang <guoqing.jiang@ionos.com>
Reviewed-by: Md Haris Iqbal <haris.iqbal@ionos.com>
Signed-off-by: Gioh Kim <gi-oh.kim@ionos.com>
Signed-off-by: Jack Wang <jinpu.wang@ionos.com>
---
 drivers/block/rnbd/rnbd-clt.c          | 42 +++++++++++---------------
 drivers/infiniband/ulp/rtrs/rtrs-clt.c |  4 +--
 drivers/infiniband/ulp/rtrs/rtrs.h     |  6 ++--
 3 files changed, 22 insertions(+), 30 deletions(-)

diff --git a/drivers/block/rnbd/rnbd-clt.c b/drivers/block/rnbd/rnbd-clt.c
index fce0f345f796..6aba7b26f260 100644
--- a/drivers/block/rnbd/rnbd-clt.c
+++ b/drivers/block/rnbd/rnbd-clt.c
@@ -312,13 +312,11 @@ static void rnbd_rerun_all_if_idle(struct rnbd_clt_session *sess)
 
 static struct rtrs_permit *rnbd_get_permit(struct rnbd_clt_session *sess,
 					     enum rtrs_clt_con_type con_type,
-					     int wait)
+					     enum wait_type wait)
 {
 	struct rtrs_permit *permit;
 
-	permit = rtrs_clt_get_permit(sess->rtrs, con_type,
-				      wait ? RTRS_PERMIT_WAIT :
-				      RTRS_PERMIT_NOWAIT);
+	permit = rtrs_clt_get_permit(sess->rtrs, con_type, wait);
 	if (likely(permit))
 		/* We have a subtle rare case here, when all permits can be
 		 * consumed before busy counter increased.  This is safe,
@@ -344,7 +342,7 @@ static void rnbd_put_permit(struct rnbd_clt_session *sess,
 
 static struct rnbd_iu *rnbd_get_iu(struct rnbd_clt_session *sess,
 				     enum rtrs_clt_con_type con_type,
-				     int wait)
+				     enum wait_type wait)
 {
 	struct rnbd_iu *iu;
 	struct rtrs_permit *permit;
@@ -354,9 +352,7 @@ static struct rnbd_iu *rnbd_get_iu(struct rnbd_clt_session *sess,
 		return NULL;
 	}
 
-	permit = rnbd_get_permit(sess, con_type,
-				  wait ? RTRS_PERMIT_WAIT :
-				  RTRS_PERMIT_NOWAIT);
+	permit = rnbd_get_permit(sess, con_type, wait);
 	if (unlikely(!permit)) {
 		kfree(iu);
 		return NULL;
@@ -440,16 +436,11 @@ static void msg_conf(void *priv, int errno)
 	schedule_work(&iu->work);
 }
 
-enum wait_type {
-	NO_WAIT = 0,
-	WAIT    = 1
-};
-
 static int send_usr_msg(struct rtrs_clt *rtrs, int dir,
 			struct rnbd_iu *iu, struct kvec *vec,
 			size_t len, struct scatterlist *sg, unsigned int sg_len,
 			void (*conf)(struct work_struct *work),
-			int *errno, enum wait_type wait)
+			int *errno, int wait)
 {
 	int err;
 	struct rtrs_clt_req_ops req_ops;
@@ -481,7 +472,8 @@ static void msg_close_conf(struct work_struct *work)
 	rnbd_clt_put_dev(dev);
 }
 
-static int send_msg_close(struct rnbd_clt_dev *dev, u32 device_id, bool wait)
+static int send_msg_close(struct rnbd_clt_dev *dev, u32 device_id,
+			  enum wait_type wait)
 {
 	struct rnbd_clt_session *sess = dev->sess;
 	struct rnbd_msg_close msg;
@@ -535,7 +527,7 @@ static void msg_open_conf(struct work_struct *work)
 			 * If server thinks its fine, but we fail to process
 			 * then be nice and send a close to server.
 			 */
-			(void)send_msg_close(dev, device_id, NO_WAIT);
+			send_msg_close(dev, device_id, RTRS_PERMIT_NOWAIT);
 		}
 	}
 	kfree(rsp);
@@ -559,7 +551,7 @@ static void msg_sess_info_conf(struct work_struct *work)
 	rnbd_clt_put_sess(sess);
 }
 
-static int send_msg_open(struct rnbd_clt_dev *dev, bool wait)
+static int send_msg_open(struct rnbd_clt_dev *dev, enum wait_type wait)
 {
 	struct rnbd_clt_session *sess = dev->sess;
 	struct rnbd_msg_open_rsp *rsp;
@@ -606,7 +598,7 @@ static int send_msg_open(struct rnbd_clt_dev *dev, bool wait)
 	return err;
 }
 
-static int send_msg_sess_info(struct rnbd_clt_session *sess, bool wait)
+static int send_msg_sess_info(struct rnbd_clt_session *sess, enum wait_type wait)
 {
 	struct rnbd_msg_sess_info_rsp *rsp;
 	struct rnbd_msg_sess_info msg;
@@ -692,7 +684,7 @@ static void remap_devs(struct rnbd_clt_session *sess)
 	 * be asynchronous.
 	 */
 
-	err = send_msg_sess_info(sess, NO_WAIT);
+	err = send_msg_sess_info(sess, RTRS_PERMIT_NOWAIT);
 	if (err) {
 		pr_err("send_msg_sess_info(\"%s\"): %d\n", sess->sessname, err);
 		return;
@@ -716,7 +708,7 @@ static void remap_devs(struct rnbd_clt_session *sess)
 			continue;
 
 		rnbd_clt_info(dev, "session reconnected, remapping device\n");
-		err = send_msg_open(dev, NO_WAIT);
+		err = send_msg_open(dev, RTRS_PERMIT_NOWAIT);
 		if (err) {
 			rnbd_clt_err(dev, "send_msg_open(): %d\n", err);
 			break;
@@ -1248,7 +1240,7 @@ find_and_get_or_create_sess(const char *sessname,
 	if (err)
 		goto close_rtrs;
 
-	err = send_msg_sess_info(sess, WAIT);
+	err = send_msg_sess_info(sess, RTRS_PERMIT_WAIT);
 	if (err)
 		goto close_rtrs;
 
@@ -1531,7 +1523,7 @@ struct rnbd_clt_dev *rnbd_clt_map_device(const char *sessname,
 		ret = -EEXIST;
 		goto put_dev;
 	}
-	ret = send_msg_open(dev, WAIT);
+	ret = send_msg_open(dev, RTRS_PERMIT_WAIT);
 	if (ret) {
 		rnbd_clt_err(dev,
 			      "map_device: failed, can't open remote device, err: %d\n",
@@ -1567,7 +1559,7 @@ struct rnbd_clt_dev *rnbd_clt_map_device(const char *sessname,
 	return dev;
 
 send_close:
-	send_msg_close(dev, dev->device_id, WAIT);
+	send_msg_close(dev, dev->device_id, RTRS_PERMIT_WAIT);
 del_dev:
 	delete_dev(dev);
 put_dev:
@@ -1636,7 +1628,7 @@ int rnbd_clt_unmap_device(struct rnbd_clt_dev *dev, bool force,
 	destroy_sysfs(dev, sysfs_self);
 	destroy_gen_disk(dev);
 	if (was_mapped && sess->rtrs)
-		send_msg_close(dev, dev->device_id, WAIT);
+		send_msg_close(dev, dev->device_id, RTRS_PERMIT_WAIT);
 
 	rnbd_clt_info(dev, "Device is unmapped\n");
 
@@ -1670,7 +1662,7 @@ int rnbd_clt_remap_device(struct rnbd_clt_dev *dev)
 	mutex_unlock(&dev->lock);
 	if (!err) {
 		rnbd_clt_info(dev, "Remapping device.\n");
-		err = send_msg_open(dev, WAIT);
+		err = send_msg_open(dev, RTRS_PERMIT_WAIT);
 		if (err)
 			rnbd_clt_err(dev, "remap_device: %d\n", err);
 	}
diff --git a/drivers/infiniband/ulp/rtrs/rtrs-clt.c b/drivers/infiniband/ulp/rtrs/rtrs-clt.c
index 0a08b4b742a3..7efd49bdc78c 100644
--- a/drivers/infiniband/ulp/rtrs/rtrs-clt.c
+++ b/drivers/infiniband/ulp/rtrs/rtrs-clt.c
@@ -103,11 +103,11 @@ static inline void __rtrs_put_permit(struct rtrs_clt *clt,
  *    up earlier.
  *
  * Context:
- *    Can sleep if @wait == RTRS_TAG_WAIT
+ *    Can sleep if @wait == RTRS_PERMIT_WAIT
  */
 struct rtrs_permit *rtrs_clt_get_permit(struct rtrs_clt *clt,
 					  enum rtrs_clt_con_type con_type,
-					  int can_wait)
+					  enum wait_type can_wait)
 {
 	struct rtrs_permit *permit;
 	DEFINE_WAIT(wait);
diff --git a/drivers/infiniband/ulp/rtrs/rtrs.h b/drivers/infiniband/ulp/rtrs/rtrs.h
index 8738e90e715a..2db1b5eb3ab0 100644
--- a/drivers/infiniband/ulp/rtrs/rtrs.h
+++ b/drivers/infiniband/ulp/rtrs/rtrs.h
@@ -63,9 +63,9 @@ struct rtrs_clt *rtrs_clt_open(struct rtrs_clt_ops *ops,
 
 void rtrs_clt_close(struct rtrs_clt *sess);
 
-enum {
+enum wait_type {
 	RTRS_PERMIT_NOWAIT = 0,
-	RTRS_PERMIT_WAIT   = 1,
+	RTRS_PERMIT_WAIT   = 1
 };
 
 /**
@@ -81,7 +81,7 @@ enum rtrs_clt_con_type {
 
 struct rtrs_permit *rtrs_clt_get_permit(struct rtrs_clt *sess,
 				    enum rtrs_clt_con_type con_type,
-				    int wait);
+				    enum wait_type wait);
 
 void rtrs_clt_put_permit(struct rtrs_clt *sess, struct rtrs_permit *permit);
 
-- 
2.25.1

Re: [PATCHv2 for-next 13/24] block/rnbd-clt: Replace {NO_WAIT,WAIT} with RTRS_PERMIT_{WAIT,NOWAIT}

[Chaitanya Kulkarni]

On 3/30/21 00:39, Gioh Kim wrote:
> From: Gioh Kim <gi-oh.kim@cloud.ionos.com>
>
> They are defined with the same value and similar meaning, let's remove
> one of them, then we can remove {WAIT,NOWAIT}.
>
> Also change the type of 'wait' from 'int' to 'enum wait_type' to make
> it clear.
>
> Cc: Jason Gunthorpe <jgg@mellanox.com>
> Cc: Leon Romanovsky <leonro@nvidia.com>
> Cc: linux-rdma@vger.kernel.org
> Signed-off-by: Guoqing Jiang <guoqing.jiang@ionos.com>
> Reviewed-by: Md Haris Iqbal <haris.iqbal@ionos.com>
> Signed-off-by: Gioh Kim <gi-oh.kim@ionos.com>
> Signed-off-by: Jack Wang <jinpu.wang@ionos.com>

It makes sense to not duplicate the enums, looks good.

Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>

[PATCHv2 for-next 14/24] block/rnbd-srv: Prevent a deadlock generated by accessing sysfs in parallel

[Gioh Kim]

From: Gioh Kim <gi-oh.kim@cloud.ionos.com>

We got a warning message below.
When server tries to close one session by force, it locks the sysfs
interface and locks the srv_sess lock.
The problem is that client can send a request to close at the same time.
By close request, server locks the srv_sess lock and locks the sysfs
to remove the sysfs interfaces.

The simplest way to prevent that situation could be just use
mutex_trylock.

[  234.153965] ======================================================
[  234.154093] WARNING: possible circular locking dependency detected
[  234.154219] 5.4.84-storage #5.4.84-1+feature+linux+5.4.y+dbg+20201216.1319+b6b887b~deb10 Tainted: G           O
[  234.154381] ------------------------------------------------------
[  234.154531] kworker/1:1H/618 is trying to acquire lock:
[  234.154651] ffff8887a09db0a8 (kn->count#132){++++}, at: kernfs_remove_by_name_ns+0x40/0x80
[  234.154819]
               but task is already holding lock:
[  234.154965] ffff8887ae5f6518 (&srv_sess->lock){+.+.}, at: rnbd_srv_rdma_ev+0x144/0x1590 [rnbd_server]
[  234.155132]
               which lock already depends on the new lock.

[  234.155311]
               the existing dependency chain (in reverse order) is:
[  234.155462]
               -> #1 (&srv_sess->lock){+.+.}:
[  234.155614]        __mutex_lock+0x134/0xcb0
[  234.155761]        rnbd_srv_sess_dev_force_close+0x36/0x50 [rnbd_server]
[  234.155889]        rnbd_srv_dev_session_force_close_store+0x69/0xc0 [rnbd_server]
[  234.156042]        kernfs_fop_write+0x13f/0x240
[  234.156162]        vfs_write+0xf3/0x280
[  234.156278]        ksys_write+0xba/0x150
[  234.156395]        do_syscall_64+0x62/0x270
[  234.156513]        entry_SYSCALL_64_after_hwframe+0x49/0xbe
[  234.156632]
               -> #0 (kn->count#132){++++}:
[  234.156782]        __lock_acquire+0x129e/0x23a0
[  234.156900]        lock_acquire+0xf3/0x210
[  234.157043]        __kernfs_remove+0x42b/0x4c0
[  234.157161]        kernfs_remove_by_name_ns+0x40/0x80
[  234.157282]        remove_files+0x3f/0xa0
[  234.157399]        sysfs_remove_group+0x4a/0xb0
[  234.157519]        rnbd_srv_destroy_dev_session_sysfs+0x19/0x30 [rnbd_server]
[  234.157648]        rnbd_srv_rdma_ev+0x14c/0x1590 [rnbd_server]
[  234.157775]        process_io_req+0x29a/0x6a0 [rtrs_server]
[  234.157924]        __ib_process_cq+0x8c/0x100 [ib_core]
[  234.158709]        ib_cq_poll_work+0x31/0xb0 [ib_core]
[  234.158834]        process_one_work+0x4e5/0xaa0
[  234.158958]        worker_thread+0x65/0x5c0
[  234.159078]        kthread+0x1e0/0x200
[  234.159194]        ret_from_fork+0x24/0x30
[  234.159309]
               other info that might help us debug this:

[  234.159513]  Possible unsafe locking scenario:

[  234.159658]        CPU0                    CPU1
[  234.159775]        ----                    ----
[  234.159891]   lock(&srv_sess->lock);
[  234.160005]                                lock(kn->count#132);
[  234.160128]                                lock(&srv_sess->lock);
[  234.160250]   lock(kn->count#132);
[  234.160364]
                *** DEADLOCK ***

[  234.160536] 3 locks held by kworker/1:1H/618:
[  234.160677]  #0: ffff8883ca1ed528 ((wq_completion)ib-comp-wq){+.+.}, at: process_one_work+0x40a/0xaa0
[  234.160840]  #1: ffff8883d2d5fe10 ((work_completion)(&cq->work)){+.+.}, at: process_one_work+0x40a/0xaa0
[  234.161003]  #2: ffff8887ae5f6518 (&srv_sess->lock){+.+.}, at: rnbd_srv_rdma_ev+0x144/0x1590 [rnbd_server]
[  234.161168]
               stack backtrace:
[  234.161312] CPU: 1 PID: 618 Comm: kworker/1:1H Tainted: G           O      5.4.84-storage #5.4.84-1+feature+linux+5.4.y+dbg+20201216.1319+b6b887b~deb10
[  234.161490] Hardware name: Supermicro H8QG6/H8QG6, BIOS 3.00       09/04/2012
[  234.161643] Workqueue: ib-comp-wq ib_cq_poll_work [ib_core]
[  234.161765] Call Trace:
[  234.161910]  dump_stack+0x96/0xe0
[  234.162028]  check_noncircular+0x29e/0x2e0
[  234.162148]  ? print_circular_bug+0x100/0x100
[  234.162267]  ? register_lock_class+0x1ad/0x8a0
[  234.162385]  ? __lock_acquire+0x68e/0x23a0
[  234.162505]  ? trace_event_raw_event_lock+0x190/0x190
[  234.162626]  __lock_acquire+0x129e/0x23a0
[  234.162746]  ? register_lock_class+0x8a0/0x8a0
[  234.162866]  lock_acquire+0xf3/0x210
[  234.162982]  ? kernfs_remove_by_name_ns+0x40/0x80
[  234.163127]  __kernfs_remove+0x42b/0x4c0
[  234.163243]  ? kernfs_remove_by_name_ns+0x40/0x80
[  234.163363]  ? kernfs_fop_readdir+0x3b0/0x3b0
[  234.163482]  ? strlen+0x1f/0x40
[  234.163596]  ? strcmp+0x30/0x50
[  234.163712]  kernfs_remove_by_name_ns+0x40/0x80
[  234.163832]  remove_files+0x3f/0xa0
[  234.163948]  sysfs_remove_group+0x4a/0xb0
[  234.164068]  rnbd_srv_destroy_dev_session_sysfs+0x19/0x30 [rnbd_server]
[  234.164196]  rnbd_srv_rdma_ev+0x14c/0x1590 [rnbd_server]
[  234.164345]  ? _raw_spin_unlock_irqrestore+0x43/0x50
[  234.164466]  ? lockdep_hardirqs_on+0x1a8/0x290
[  234.164597]  ? mlx4_ib_poll_cq+0x927/0x1280 [mlx4_ib]
[  234.164732]  ? rnbd_get_sess_dev+0x270/0x270 [rnbd_server]
[  234.164859]  process_io_req+0x29a/0x6a0 [rtrs_server]
[  234.164982]  ? rnbd_get_sess_dev+0x270/0x270 [rnbd_server]
[  234.165130]  __ib_process_cq+0x8c/0x100 [ib_core]
[  234.165279]  ib_cq_poll_work+0x31/0xb0 [ib_core]
[  234.165404]  process_one_work+0x4e5/0xaa0
[  234.165550]  ? pwq_dec_nr_in_flight+0x160/0x160
[  234.165675]  ? do_raw_spin_lock+0x119/0x1d0
[  234.165796]  worker_thread+0x65/0x5c0
[  234.165914]  ? process_one_work+0xaa0/0xaa0
[  234.166031]  kthread+0x1e0/0x200
[  234.166147]  ? kthread_create_worker_on_cpu+0xc0/0xc0
[  234.166268]  ret_from_fork+0x24/0x30
[  234.251591] rnbd_server L243: </dev/loop1@close_device_session>: Device closed
[  234.604221] rnbd_server L264: RTRS Session close_device_session disconnected

Signed-off-by: Gioh Kim <gi-oh.kim@ionos.com>
Signed-off-by: Md Haris Iqbal <haris.iqbal@ionos.com>
Signed-off-by: Jack Wang <jinpu.wang@ionos.com>
---
 drivers/block/rnbd/rnbd-srv.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/block/rnbd/rnbd-srv.c b/drivers/block/rnbd/rnbd-srv.c
index 895e9c313ff0..f284620ef0d3 100644
--- a/drivers/block/rnbd/rnbd-srv.c
+++ b/drivers/block/rnbd/rnbd-srv.c
@@ -340,7 +340,9 @@ void rnbd_srv_sess_dev_force_close(struct rnbd_srv_sess_dev *sess_dev)
 	struct rnbd_srv_session	*sess = sess_dev->sess;
 
 	sess_dev->keep_id = true;
-	mutex_lock(&sess->lock);
+	/* It is already started to close by client's close message. */
+	if (!mutex_trylock(&sess->lock))
+		return;
 	rnbd_srv_destroy_dev_session_sysfs(sess_dev);
 	mutex_unlock(&sess->lock);
 }
-- 
2.25.1

[PATCHv2 for-next 15/24] block/rnbd-srv: Remove force_close file after holding a lock

[Gioh Kim]

From: Gioh Kim <gi-oh.kim@cloud.ionos.com>

We changed the rnbd_srv_sess_dev_force_close to use try-lock
because rnbd_srv_sess_dev_force_close and process_msg_close
can generate a deadlock.

Now rnbd_srv_sess_dev_force_close would do nothing
if it fails to get the lock. So removing the force_close
file should be moved to after the lock. Or the force_close
file is removed but the others are not removed.

Signed-off-by: Gioh Kim <gi-oh.kim@ionos.com>
Signed-off-by: Md Haris Iqbal <haris.iqbal@ionos.com>
Signed-off-by: Jack Wang <jinpu.wang@ionos.com>
---
 drivers/block/rnbd/rnbd-srv-sysfs.c | 5 +----
 drivers/block/rnbd/rnbd-srv.c       | 5 ++++-
 drivers/block/rnbd/rnbd-srv.h       | 3 ++-
 3 files changed, 7 insertions(+), 6 deletions(-)

diff --git a/drivers/block/rnbd/rnbd-srv-sysfs.c b/drivers/block/rnbd/rnbd-srv-sysfs.c
index 278a981302b9..76f9c08f611f 100644
--- a/drivers/block/rnbd/rnbd-srv-sysfs.c
+++ b/drivers/block/rnbd/rnbd-srv-sysfs.c
@@ -147,10 +147,7 @@ static ssize_t rnbd_srv_dev_session_force_close_store(struct kobject *kobj,
 	}
 
 	rnbd_srv_info(sess_dev, "force close requested\n");
-
-	/* first remove sysfs itself to avoid deadlock */
-	sysfs_remove_file_self(&sess_dev->kobj, &attr->attr);
-	rnbd_srv_sess_dev_force_close(sess_dev);
+	rnbd_srv_sess_dev_force_close(sess_dev, attr);
 
 	return count;
 }
diff --git a/drivers/block/rnbd/rnbd-srv.c b/drivers/block/rnbd/rnbd-srv.c
index f284620ef0d3..a71b6f7662f5 100644
--- a/drivers/block/rnbd/rnbd-srv.c
+++ b/drivers/block/rnbd/rnbd-srv.c
@@ -335,7 +335,8 @@ static int rnbd_srv_link_ev(struct rtrs_srv *rtrs,
 	}
 }
 
-void rnbd_srv_sess_dev_force_close(struct rnbd_srv_sess_dev *sess_dev)
+void rnbd_srv_sess_dev_force_close(struct rnbd_srv_sess_dev *sess_dev,
+				   struct kobj_attribute *attr)
 {
 	struct rnbd_srv_session	*sess = sess_dev->sess;
 
@@ -343,6 +344,8 @@ void rnbd_srv_sess_dev_force_close(struct rnbd_srv_sess_dev *sess_dev)
 	/* It is already started to close by client's close message. */
 	if (!mutex_trylock(&sess->lock))
 		return;
+	/* first remove sysfs itself to avoid deadlock */
+	sysfs_remove_file_self(&sess_dev->kobj, &attr->attr);
 	rnbd_srv_destroy_dev_session_sysfs(sess_dev);
 	mutex_unlock(&sess->lock);
 }
diff --git a/drivers/block/rnbd/rnbd-srv.h b/drivers/block/rnbd/rnbd-srv.h
index 120e6d64cb82..b513021efc92 100644
--- a/drivers/block/rnbd/rnbd-srv.h
+++ b/drivers/block/rnbd/rnbd-srv.h
@@ -72,7 +72,8 @@ struct rnbd_srv_sess_dev {
 	struct rnbd_srv_fault_inject    fault_inject;
 };
 
-void rnbd_srv_sess_dev_force_close(struct rnbd_srv_sess_dev *sess_dev);
+void rnbd_srv_sess_dev_force_close(struct rnbd_srv_sess_dev *sess_dev,
+				   struct kobj_attribute *attr);
 /* rnbd-srv-sysfs.c */
 
 int rnbd_srv_create_dev_sysfs(struct rnbd_srv_dev *dev,
-- 
2.25.1

[PATCHv2 for-next 16/24] block/rnbd-clt: Improve find_or_create_sess() return check

[Gioh Kim]

From: Tom Rix <trix@redhat.com>

clang static analysis reports this problem

rnbd-clt.c:1212:11: warning: Branch condition evaluates to a
  garbage value
        else if (!first)
                 ^~~~~~

This is triggered in the find_and_get_or_create_sess() call
because the variable first is not initialized and the
earlier check is specifically for

	if (sess == ERR_PTR(-ENOMEM))

This is false positive.

But the if-check can be reduced by initializing first to
false and then returning if the call to find_or_creat_sess()
does not set it to true.  When it remains false, either
sess will be valid or not.  The not case is caught by
find_and_get_or_create_sess()'s caller rnbd_clt_map_device()

	sess = find_and_get_or_create_sess(...);
	if (IS_ERR(sess))
		return ERR_CAST(sess);

Since find_and_get_or_create_sess() initializes first to false
setting it in find_or_create_sess() is not needed.

Signed-off-by: Tom Rix <trix@redhat.com>
Signed-off-by: Jack Wang <jinpu.wang@ionos.com>
Signed-off-by: Gioh Kim <gi-oh.kim@ionos.com>
---
 drivers/block/rnbd/rnbd-clt.c | 10 ++++------
 1 file changed, 4 insertions(+), 6 deletions(-)

diff --git a/drivers/block/rnbd/rnbd-clt.c b/drivers/block/rnbd/rnbd-clt.c
index 6aba7b26f260..6f955a937f40 100644
--- a/drivers/block/rnbd/rnbd-clt.c
+++ b/drivers/block/rnbd/rnbd-clt.c
@@ -915,6 +915,7 @@ static struct rnbd_clt_session *__find_and_get_sess(const char *sessname)
 	return NULL;
 }
 
+/* caller is responsible for initializing 'first' to false */
 static struct
 rnbd_clt_session *find_or_create_sess(const char *sessname, bool *first)
 {
@@ -930,8 +931,7 @@ rnbd_clt_session *find_or_create_sess(const char *sessname, bool *first)
 		}
 		list_add(&sess->list, &sess_list);
 		*first = true;
-	} else
-		*first = false;
+	}
 	mutex_unlock(&sess_lock);
 
 	return sess;
@@ -1200,13 +1200,11 @@ find_and_get_or_create_sess(const char *sessname,
 	struct rnbd_clt_session *sess;
 	struct rtrs_attrs attrs;
 	int err;
-	bool first;
+	bool first = false;
 	struct rtrs_clt_ops rtrs_ops;
 
 	sess = find_or_create_sess(sessname, &first);
-	if (sess == ERR_PTR(-ENOMEM))
-		return ERR_PTR(-ENOMEM);
-	else if (!first)
+	if (!first)
 		return sess;
 
 	if (!path_cnt) {
-- 
2.25.1

[PATCHv2 for-next 17/24] block/rnbd-clt: Fix missing a memory free when unloading the module

[Gioh Kim]

From: Gioh Kim <gi-oh.kim@cloud.ionos.com>

When unloading the rnbd-clt module, it does not free a memory
including the filename of the symbolic link to /sys/block/rnbdX.

It is found by kmemleak as below.

unreferenced object 0xffff9f1a83d3c740 (size 16):
  comm "bash", pid 736, jiffies 4295179665 (age 9841.310s)
  hex dump (first 16 bytes):
    21 64 65 76 21 6e 75 6c 6c 62 30 40 62 6c 61 00  !dev!nullb0@bla.
  backtrace:
    [<0000000039f0c55e>] 0xffffffffc0456c24
    [<000000001aab9513>] kernfs_fop_write+0xcf/0x1c0
    [<00000000db5aa4b3>] vfs_write+0xdb/0x1d0
    [<000000007a2e2207>] ksys_write+0x65/0xe0
    [<00000000055e280a>] do_syscall_64+0x50/0x1b0
    [<00000000c2b51831>] entry_SYSCALL_64_after_hwframe+0x49/0xbe

Signed-off-by: Gioh Kim <gi-oh.kim@ionos.com>
Signed-off-by: Jack Wang <jinpu.wang@ionos.com>
---
 drivers/block/rnbd/rnbd-clt-sysfs.c | 10 +++++++---
 1 file changed, 7 insertions(+), 3 deletions(-)

diff --git a/drivers/block/rnbd/rnbd-clt-sysfs.c b/drivers/block/rnbd/rnbd-clt-sysfs.c
index 2452eb67547c..885074f2f734 100644
--- a/drivers/block/rnbd/rnbd-clt-sysfs.c
+++ b/drivers/block/rnbd/rnbd-clt-sysfs.c
@@ -432,10 +432,14 @@ void rnbd_clt_remove_dev_symlink(struct rnbd_clt_dev *dev)
 	 * i.e. rnbd_clt_unmap_dev_store() leading to a sysfs warning because
 	 * of sysfs link already was removed already.
 	 */
-	if (dev->blk_symlink_name && try_module_get(THIS_MODULE)) {
-		sysfs_remove_link(rnbd_devs_kobj, dev->blk_symlink_name);
+	if (dev->blk_symlink_name) {
+		if (try_module_get(THIS_MODULE)) {
+			sysfs_remove_link(rnbd_devs_kobj, dev->blk_symlink_name);
+			module_put(THIS_MODULE);
+		}
+		/* It should be freed always. */
 		kfree(dev->blk_symlink_name);
-		module_put(THIS_MODULE);
+		dev->blk_symlink_name = NULL;
 	}
 }
 
-- 
2.25.1

[PATCHv2 for-next 18/24] block/rnbd-clt: Support polling mode for IO latency optimization

[Gioh Kim]

From: Gioh Kim <gi-oh.kim@cloud.ionos.com>

RNBD can make double-queues for irq-mode and poll-mode.
For example, on 4-CPU system 8 request-queues are created,
4 for irq-mode and 4 for poll-mode.
If the IO has HIPRI flag, the block-layer will call .poll function
of RNBD. Then IO is sent to the poll-mode queue.
Add optional nr_poll_queues argument for map_devices interface.

To support polling of RNBD, RTRS client creates connections
for both of irq-mode and direct-poll-mode.

For example, on 4-CPU system it could've create 5 connections:
con[0] => user message (softirq cq)
con[1:4] => softirq cq

After this patch, it can create 9 connections:
con[0] => user message (softirq cq)
con[1:4] => softirq cq
con[5:8] => DIRECT-POLL cq

Cc: Jason Gunthorpe <jgg@mellanox.com>
Cc: Leon Romanovsky <leonro@nvidia.com>
Cc: linux-rdma@vger.kernel.org
Signed-off-by: Gioh Kim <gi-oh.kim@ionos.com>
Signed-off-by: Jack Wang <jinpu.wang@ionos.com>
---
 drivers/block/rnbd/rnbd-clt-sysfs.c    | 56 +++++++++++++----
 drivers/block/rnbd/rnbd-clt.c          | 85 +++++++++++++++++++++++---
 drivers/block/rnbd/rnbd-clt.h          |  5 +-
 drivers/infiniband/ulp/rtrs/rtrs-clt.c | 62 +++++++++++++++----
 drivers/infiniband/ulp/rtrs/rtrs-pri.h |  1 +
 drivers/infiniband/ulp/rtrs/rtrs.h     |  3 +-
 6 files changed, 178 insertions(+), 34 deletions(-)

diff --git a/drivers/block/rnbd/rnbd-clt-sysfs.c b/drivers/block/rnbd/rnbd-clt-sysfs.c
index 885074f2f734..9ea4da7f894a 100644
--- a/drivers/block/rnbd/rnbd-clt-sysfs.c
+++ b/drivers/block/rnbd/rnbd-clt-sysfs.c
@@ -34,6 +34,7 @@ enum {
 	RNBD_OPT_DEV_PATH	= 1 << 2,
 	RNBD_OPT_ACCESS_MODE	= 1 << 3,
 	RNBD_OPT_SESSNAME	= 1 << 6,
+	RNBD_OPT_NR_POLL_QUEUES	= 1 << 7,
 };
 
 static const unsigned int rnbd_opt_mandatory[] = {
@@ -42,12 +43,13 @@ static const unsigned int rnbd_opt_mandatory[] = {
 };
 
 static const match_table_t rnbd_opt_tokens = {
-	{RNBD_OPT_PATH,		"path=%s"	},
-	{RNBD_OPT_DEV_PATH,	"device_path=%s"},
-	{RNBD_OPT_DEST_PORT,	"dest_port=%d"  },
-	{RNBD_OPT_ACCESS_MODE,	"access_mode=%s"},
-	{RNBD_OPT_SESSNAME,	"sessname=%s"	},
-	{RNBD_OPT_ERR,		NULL		},
+	{RNBD_OPT_PATH,			"path=%s"		},
+	{RNBD_OPT_DEV_PATH,		"device_path=%s"	},
+	{RNBD_OPT_DEST_PORT,		"dest_port=%d"  	},
+	{RNBD_OPT_ACCESS_MODE,		"access_mode=%s"	},
+	{RNBD_OPT_SESSNAME,		"sessname=%s"		},
+	{RNBD_OPT_NR_POLL_QUEUES,	"nr_poll_queues=%d"	},
+	{RNBD_OPT_ERR,			NULL			},
 };
 
 struct rnbd_map_options {
@@ -57,6 +59,7 @@ struct rnbd_map_options {
 	char *pathname;
 	u16 *dest_port;
 	enum rnbd_access_mode *access_mode;
+	u32 *nr_poll_queues;
 };
 
 static int rnbd_clt_parse_map_options(const char *buf, size_t max_path_cnt,
@@ -68,7 +71,7 @@ static int rnbd_clt_parse_map_options(const char *buf, size_t max_path_cnt,
 	int opt_mask = 0;
 	int token;
 	int ret = -EINVAL;
-	int i, dest_port;
+	int i, dest_port, nr_poll_queues;
 	int p_cnt = 0;
 
 	options = kstrdup(buf, GFP_KERNEL);
@@ -178,6 +181,19 @@ static int rnbd_clt_parse_map_options(const char *buf, size_t max_path_cnt,
 			kfree(p);
 			break;
 
+		case RNBD_OPT_NR_POLL_QUEUES:
+			if (match_int(args, &nr_poll_queues) || nr_poll_queues < -1 ||
+			    nr_poll_queues > (int)nr_cpu_ids) {
+				pr_err("bad nr_poll_queues parameter '%d'\n",
+				       nr_poll_queues);
+				ret = -EINVAL;
+				goto out;
+			}
+			if (nr_poll_queues == -1)
+				nr_poll_queues = nr_cpu_ids;
+			*opt->nr_poll_queues = nr_poll_queues;
+			break;
+
 		default:
 			pr_err("map_device: Unknown parameter or missing value '%s'\n",
 			       p);
@@ -227,6 +243,20 @@ static ssize_t state_show(struct kobject *kobj,
 
 static struct kobj_attribute rnbd_clt_state_attr = __ATTR_RO(state);
 
+static ssize_t nr_poll_queues_show(struct kobject *kobj,
+				   struct kobj_attribute *attr, char *page)
+{
+	struct rnbd_clt_dev *dev;
+
+	dev = container_of(kobj, struct rnbd_clt_dev, kobj);
+
+	return snprintf(page, PAGE_SIZE, "%d\n",
+			dev->nr_poll_queues);
+}
+
+static struct kobj_attribute rnbd_clt_nr_poll_queues =
+	__ATTR_RO(nr_poll_queues);
+
 static ssize_t mapping_path_show(struct kobject *kobj,
 				 struct kobj_attribute *attr, char *page)
 {
@@ -421,6 +451,7 @@ static struct attribute *rnbd_dev_attrs[] = {
 	&rnbd_clt_state_attr.attr,
 	&rnbd_clt_session_attr.attr,
 	&rnbd_clt_access_mode.attr,
+	&rnbd_clt_nr_poll_queues.attr,
 	NULL,
 };
 
@@ -469,7 +500,7 @@ static ssize_t rnbd_clt_map_device_show(struct kobject *kobj,
 					 char *page)
 {
 	return scnprintf(page, PAGE_SIZE,
-			 "Usage: echo \"[dest_port=server port number] sessname=<name of the rtrs session> path=<[srcaddr@]dstaddr> [path=<[srcaddr@]dstaddr>] device_path=<full path on remote side> [access_mode=<ro|rw|migration>]\" > %s\n\naddr ::= [ ip:<ipv4> | ip:<ipv6> | gid:<gid> ]\n",
+			 "Usage: echo \"[dest_port=server port number] sessname=<name of the rtrs session> path=<[srcaddr@]dstaddr> [path=<[srcaddr@]dstaddr>] device_path=<full path on remote side> [access_mode=<ro|rw|migration>] [nr_poll_queues=<number of queues>]\" > %s\n\naddr ::= [ ip:<ipv4> | ip:<ipv6> | gid:<gid> ]\n",
 			 attr->attr.name);
 }
 
@@ -541,6 +572,7 @@ static ssize_t rnbd_clt_map_device_store(struct kobject *kobj,
 	char sessname[NAME_MAX];
 	enum rnbd_access_mode access_mode = RNBD_ACCESS_RW;
 	u16 port_nr = RTRS_PORT;
+	u32 nr_poll_queues = 0;
 
 	struct sockaddr_storage *addrs;
 	struct rtrs_addr paths[6];
@@ -552,6 +584,7 @@ static ssize_t rnbd_clt_map_device_store(struct kobject *kobj,
 	opt.pathname = pathname;
 	opt.dest_port = &port_nr;
 	opt.access_mode = &access_mode;
+	opt.nr_poll_queues = &nr_poll_queues;
 	addrs = kcalloc(ARRAY_SIZE(paths) * 2, sizeof(*addrs), GFP_KERNEL);
 	if (!addrs)
 		return -ENOMEM;
@@ -565,12 +598,13 @@ static ssize_t rnbd_clt_map_device_store(struct kobject *kobj,
 	if (ret)
 		goto out;
 
-	pr_info("Mapping device %s on session %s, (access_mode: %s)\n",
+	pr_info("Mapping device %s on session %s, (access_mode: %s, nr_poll_queues: %d)\n",
 		pathname, sessname,
-		rnbd_access_mode_str(access_mode));
+		rnbd_access_mode_str(access_mode),
+		nr_poll_queues);
 
 	dev = rnbd_clt_map_device(sessname, paths, path_cnt, port_nr, pathname,
-				  access_mode);
+				  access_mode, nr_poll_queues);
 	if (IS_ERR(dev)) {
 		ret = PTR_ERR(dev);
 		goto out;
diff --git a/drivers/block/rnbd/rnbd-clt.c b/drivers/block/rnbd/rnbd-clt.c
index 6f955a937f40..998cadd73d47 100644
--- a/drivers/block/rnbd/rnbd-clt.c
+++ b/drivers/block/rnbd/rnbd-clt.c
@@ -1171,9 +1171,54 @@ static blk_status_t rnbd_queue_rq(struct blk_mq_hw_ctx *hctx,
 	return ret;
 }
 
+static int rnbd_rdma_poll(struct blk_mq_hw_ctx *hctx)
+{
+	struct rnbd_queue *q = hctx->driver_data;
+	struct rnbd_clt_dev *dev = q->dev;
+	int cnt;
+
+	cnt = rtrs_clt_rdma_cq_direct(dev->sess->rtrs, hctx->queue_num);
+	return cnt;
+}
+
+static int rnbd_rdma_map_queues(struct blk_mq_tag_set *set)
+{
+	struct rnbd_clt_session *sess = set->driver_data;
+
+	/* shared read/write queues */
+	set->map[HCTX_TYPE_DEFAULT].nr_queues = num_online_cpus();
+	set->map[HCTX_TYPE_DEFAULT].queue_offset = 0;
+	set->map[HCTX_TYPE_READ].nr_queues = num_online_cpus();
+	set->map[HCTX_TYPE_READ].queue_offset = 0;
+	blk_mq_map_queues(&set->map[HCTX_TYPE_DEFAULT]);
+	blk_mq_map_queues(&set->map[HCTX_TYPE_READ]);
+
+	if (sess->nr_poll_queues) {
+		/* dedicated queue for poll */
+		set->map[HCTX_TYPE_POLL].nr_queues = sess->nr_poll_queues;
+		set->map[HCTX_TYPE_POLL].queue_offset = set->map[HCTX_TYPE_READ].queue_offset +
+			set->map[HCTX_TYPE_READ].nr_queues;
+		blk_mq_map_queues(&set->map[HCTX_TYPE_POLL]);
+		pr_info("[session=%s] mapped %d/%d/%d default/read/poll queues.\n",
+			sess->sessname,
+			set->map[HCTX_TYPE_DEFAULT].nr_queues,
+			set->map[HCTX_TYPE_READ].nr_queues,
+			set->map[HCTX_TYPE_POLL].nr_queues);
+	} else {
+		pr_info("[session=%s] mapped %d/%d default/read queues.\n",
+			sess->sessname,
+			set->map[HCTX_TYPE_DEFAULT].nr_queues,
+			set->map[HCTX_TYPE_READ].nr_queues);
+	}
+
+	return 0;
+}
+
 static struct blk_mq_ops rnbd_mq_ops = {
 	.queue_rq	= rnbd_queue_rq,
 	.complete	= rnbd_softirq_done_fn,
+	.map_queues     = rnbd_rdma_map_queues,
+	.poll           = rnbd_rdma_poll,
 };
 
 static int setup_mq_tags(struct rnbd_clt_session *sess)
@@ -1187,7 +1232,15 @@ static int setup_mq_tags(struct rnbd_clt_session *sess)
 	tag_set->flags		= BLK_MQ_F_SHOULD_MERGE |
 				  BLK_MQ_F_TAG_QUEUE_SHARED;
 	tag_set->cmd_size	= sizeof(struct rnbd_iu) + RNBD_RDMA_SGL_SIZE;
-	tag_set->nr_hw_queues	= num_online_cpus();
+
+	/* for HCTX_TYPE_DEFAULT, HCTX_TYPE_READ, HCTX_TYPE_POLL */
+	tag_set->nr_maps        = sess->nr_poll_queues ? HCTX_MAX_TYPES : 2;
+	/*
+	 * HCTX_TYPE_DEFAULT and HCTX_TYPE_READ share one set of queues
+	 * others are for HCTX_TYPE_POLL
+	 */
+	tag_set->nr_hw_queues	= num_online_cpus() + sess->nr_poll_queues;
+	tag_set->driver_data    = sess;
 
 	return blk_mq_alloc_tag_set(tag_set);
 }
@@ -1195,7 +1248,7 @@ static int setup_mq_tags(struct rnbd_clt_session *sess)
 static struct rnbd_clt_session *
 find_and_get_or_create_sess(const char *sessname,
 			    const struct rtrs_addr *paths,
-			    size_t path_cnt, u16 port_nr)
+			    size_t path_cnt, u16 port_nr, u32 nr_poll_queues)
 {
 	struct rnbd_clt_session *sess;
 	struct rtrs_attrs attrs;
@@ -1204,6 +1257,17 @@ find_and_get_or_create_sess(const char *sessname,
 	struct rtrs_clt_ops rtrs_ops;
 
 	sess = find_or_create_sess(sessname, &first);
+	if (sess == ERR_PTR(-ENOMEM))
+		return ERR_PTR(-ENOMEM);
+	else if ((nr_poll_queues && !first) ||  (!nr_poll_queues && sess->nr_poll_queues)) {
+		/*
+		 * A device MUST have its own session to use the polling-mode.
+		 * It must fail to map new device with the same session.
+		 */
+		err = -EINVAL;
+		goto put_sess;
+	}
+
 	if (!first)
 		return sess;
 
@@ -1225,7 +1289,7 @@ find_and_get_or_create_sess(const char *sessname,
 				   0, /* Do not use pdu of rtrs */
 				   RECONNECT_DELAY, BMAX_SEGMENTS,
 				   BLK_MAX_SEGMENT_SIZE,
-				   MAX_RECONNECTS);
+				   MAX_RECONNECTS, nr_poll_queues);
 	if (IS_ERR(sess->rtrs)) {
 		err = PTR_ERR(sess->rtrs);
 		goto wake_up_and_put;
@@ -1233,6 +1297,7 @@ find_and_get_or_create_sess(const char *sessname,
 	rtrs_clt_query(sess->rtrs, &attrs);
 	sess->max_io_size = attrs.max_io_size;
 	sess->queue_depth = attrs.queue_depth;
+	sess->nr_poll_queues = nr_poll_queues;
 
 	err = setup_mq_tags(sess);
 	if (err)
@@ -1376,7 +1441,8 @@ static int rnbd_client_setup_device(struct rnbd_clt_dev *dev)
 
 static struct rnbd_clt_dev *init_dev(struct rnbd_clt_session *sess,
 				      enum rnbd_access_mode access_mode,
-				      const char *pathname)
+				      const char *pathname,
+				      u32 nr_poll_queues)
 {
 	struct rnbd_clt_dev *dev;
 	int ret;
@@ -1385,7 +1451,8 @@ static struct rnbd_clt_dev *init_dev(struct rnbd_clt_session *sess,
 	if (!dev)
 		return ERR_PTR(-ENOMEM);
 
-	dev->hw_queues = kcalloc(nr_cpu_ids, sizeof(*dev->hw_queues),
+	dev->hw_queues = kcalloc(nr_cpu_ids /* softirq */ + nr_poll_queues /* poll */,
+				 sizeof(*dev->hw_queues),
 				 GFP_KERNEL);
 	if (!dev->hw_queues) {
 		ret = -ENOMEM;
@@ -1411,6 +1478,7 @@ static struct rnbd_clt_dev *init_dev(struct rnbd_clt_session *sess,
 	dev->clt_device_id	= ret;
 	dev->sess		= sess;
 	dev->access_mode	= access_mode;
+	dev->nr_poll_queues	= nr_poll_queues;
 	mutex_init(&dev->lock);
 	refcount_set(&dev->refcount, 1);
 	dev->dev_state = DEV_STATE_INIT;
@@ -1497,7 +1565,8 @@ struct rnbd_clt_dev *rnbd_clt_map_device(const char *sessname,
 					   struct rtrs_addr *paths,
 					   size_t path_cnt, u16 port_nr,
 					   const char *pathname,
-					   enum rnbd_access_mode access_mode)
+					   enum rnbd_access_mode access_mode,
+					   u32 nr_poll_queues)
 {
 	struct rnbd_clt_session *sess;
 	struct rnbd_clt_dev *dev;
@@ -1506,11 +1575,11 @@ struct rnbd_clt_dev *rnbd_clt_map_device(const char *sessname,
 	if (unlikely(exists_devpath(pathname, sessname)))
 		return ERR_PTR(-EEXIST);
 
-	sess = find_and_get_or_create_sess(sessname, paths, path_cnt, port_nr);
+	sess = find_and_get_or_create_sess(sessname, paths, path_cnt, port_nr, nr_poll_queues);
 	if (IS_ERR(sess))
 		return ERR_CAST(sess);
 
-	dev = init_dev(sess, access_mode, pathname);
+	dev = init_dev(sess, access_mode, pathname, nr_poll_queues);
 	if (IS_ERR(dev)) {
 		pr_err("map_device: failed to map device '%s' from session %s, can't initialize device, err: %ld\n",
 		       pathname, sess->sessname, PTR_ERR(dev));
diff --git a/drivers/block/rnbd/rnbd-clt.h b/drivers/block/rnbd/rnbd-clt.h
index d2a709f5d7ed..685468ccb178 100644
--- a/drivers/block/rnbd/rnbd-clt.h
+++ b/drivers/block/rnbd/rnbd-clt.h
@@ -90,6 +90,7 @@ struct rnbd_clt_session {
 	int			queue_depth;
 	u32			max_io_size;
 	struct blk_mq_tag_set	tag_set;
+	u32			nr_poll_queues;
 	struct mutex		lock; /* protects state and devs_list */
 	struct list_head        devs_list; /* list of struct rnbd_clt_dev */
 	refcount_t		refcount;
@@ -126,6 +127,7 @@ struct rnbd_clt_dev {
 	enum rnbd_clt_dev_state	dev_state;
 	char			*pathname;
 	enum rnbd_access_mode	access_mode;
+	u32			nr_poll_queues;
 	bool			read_only;
 	bool			rotational;
 	bool			wc;
@@ -156,7 +158,8 @@ struct rnbd_clt_dev *rnbd_clt_map_device(const char *sessname,
 					   struct rtrs_addr *paths,
 					   size_t path_cnt, u16 port_nr,
 					   const char *pathname,
-					   enum rnbd_access_mode access_mode);
+					   enum rnbd_access_mode access_mode,
+					   u32 nr_poll_queues);
 int rnbd_clt_unmap_device(struct rnbd_clt_dev *dev, bool force,
 			   const struct attribute *sysfs_self);
 
diff --git a/drivers/infiniband/ulp/rtrs/rtrs-clt.c b/drivers/infiniband/ulp/rtrs/rtrs-clt.c
index 7efd49bdc78c..cf9dbcbc11e7 100644
--- a/drivers/infiniband/ulp/rtrs/rtrs-clt.c
+++ b/drivers/infiniband/ulp/rtrs/rtrs-clt.c
@@ -174,7 +174,7 @@ struct rtrs_clt_con *rtrs_permit_to_clt_con(struct rtrs_clt_sess *sess,
 	int id = 0;
 
 	if (likely(permit->con_type == RTRS_IO_CON))
-		id = (permit->cpu_id % (sess->s.con_num - 1)) + 1;
+		id = (permit->cpu_id % (sess->s.irq_con_num - 1)) + 1;
 
 	return to_clt_con(sess->s.con[id]);
 }
@@ -1400,23 +1400,29 @@ static void rtrs_clt_close_work(struct work_struct *work);
 static struct rtrs_clt_sess *alloc_sess(struct rtrs_clt *clt,
 					 const struct rtrs_addr *path,
 					 size_t con_num, u16 max_segments,
-					 size_t max_segment_size)
+					 size_t max_segment_size, u32 nr_poll_queues)
 {
 	struct rtrs_clt_sess *sess;
 	int err = -ENOMEM;
 	int cpu;
+	size_t total_con;
 
 	sess = kzalloc(sizeof(*sess), GFP_KERNEL);
 	if (!sess)
 		goto err;
 
-	/* Extra connection for user messages */
-	con_num += 1;
-
-	sess->s.con = kcalloc(con_num, sizeof(*sess->s.con), GFP_KERNEL);
+	/*
+	 * irqmode and poll
+	 * +1: Extra connection for user messages
+	 */
+	total_con = con_num + nr_poll_queues + 1;
+	sess->s.con = kcalloc(total_con, sizeof(*sess->s.con), GFP_KERNEL);
 	if (!sess->s.con)
 		goto err_free_sess;
 
+	sess->s.con_num = total_con;
+	sess->s.irq_con_num = con_num + 1;
+
 	sess->stats = kzalloc(sizeof(*sess->stats), GFP_KERNEL);
 	if (!sess->stats)
 		goto err_free_con;
@@ -1435,7 +1441,6 @@ static struct rtrs_clt_sess *alloc_sess(struct rtrs_clt *clt,
 		memcpy(&sess->s.src_addr, path->src,
 		       rdma_addr_size((struct sockaddr *)path->src));
 	strlcpy(sess->s.sessname, clt->sessname, sizeof(sess->s.sessname));
-	sess->s.con_num = con_num;
 	sess->clt = clt;
 	sess->max_pages_per_mr = max_segments * max_segment_size >> 12;
 	init_waitqueue_head(&sess->state_wq);
@@ -1576,9 +1581,14 @@ static int create_con_cq_qp(struct rtrs_clt_con *con)
 	}
 	cq_size = max_send_wr + max_recv_wr;
 	cq_vector = con->cpu % sess->s.dev->ib_dev->num_comp_vectors;
-	err = rtrs_cq_qp_create(&sess->s, &con->c, sess->max_send_sge,
-				 cq_vector, cq_size, max_send_wr,
-				 max_recv_wr, IB_POLL_SOFTIRQ);
+	if (con->c.cid >= sess->s.irq_con_num)
+		err = rtrs_cq_qp_create(&sess->s, &con->c, sess->max_send_sge,
+					cq_vector, cq_size, max_send_wr,
+					max_recv_wr, IB_POLL_DIRECT);
+	else
+		err = rtrs_cq_qp_create(&sess->s, &con->c, sess->max_send_sge,
+					cq_vector, cq_size, max_send_wr,
+					max_recv_wr, IB_POLL_SOFTIRQ);
 	/*
 	 * In case of error we do not bother to clean previous allocations,
 	 * since destroy_con_cq_qp() must be called.
@@ -2631,6 +2641,7 @@ static void free_clt(struct rtrs_clt *clt)
  * @max_segment_size: Max. size of one segment
  * @max_reconnect_attempts: Number of times to reconnect on error before giving
  *			    up, 0 for * disabled, -1 for forever
+ * @nr_poll_queues: number of polling mode connection using IB_POLL_DIRECT flag
  *
  * Starts session establishment with the rtrs_server. The function can block
  * up to ~2000ms before it returns.
@@ -2644,7 +2655,7 @@ struct rtrs_clt *rtrs_clt_open(struct rtrs_clt_ops *ops,
 				 size_t pdu_sz, u8 reconnect_delay_sec,
 				 u16 max_segments,
 				 size_t max_segment_size,
-				 s16 max_reconnect_attempts)
+			         s16 max_reconnect_attempts, u32 nr_poll_queues)
 {
 	struct rtrs_clt_sess *sess, *tmp;
 	struct rtrs_clt *clt;
@@ -2662,7 +2673,7 @@ struct rtrs_clt *rtrs_clt_open(struct rtrs_clt_ops *ops,
 		struct rtrs_clt_sess *sess;
 
 		sess = alloc_sess(clt, &paths[i], nr_cpu_ids,
-				  max_segments, max_segment_size);
+				  max_segments, max_segment_size, nr_poll_queues);
 		if (IS_ERR(sess)) {
 			err = PTR_ERR(sess);
 			goto close_all_sess;
@@ -2887,6 +2898,31 @@ int rtrs_clt_request(int dir, struct rtrs_clt_req_ops *ops,
 }
 EXPORT_SYMBOL(rtrs_clt_request);
 
+int rtrs_clt_rdma_cq_direct(struct rtrs_clt *clt, unsigned int index)
+{
+	int cnt;
+	struct rtrs_con *con;
+	struct rtrs_clt_sess *sess;
+	struct path_it it;
+
+	rcu_read_lock();
+	for (path_it_init(&it, clt);
+	     (sess = it.next_path(&it)) && it.i < it.clt->paths_num; it.i++) {
+		if (unlikely(READ_ONCE(sess->state) != RTRS_CLT_CONNECTED))
+			continue;
+
+		con = sess->s.con[index + 1];
+		cnt = ib_process_cq_direct(con->cq, -1);
+		if (likely(cnt))
+			break;
+	}
+	path_it_deinit(&it);
+	rcu_read_unlock();
+
+	return cnt;
+}
+EXPORT_SYMBOL(rtrs_clt_rdma_cq_direct);
+
 /**
  * rtrs_clt_query() - queries RTRS session attributes
  *@clt: session pointer
@@ -2916,7 +2952,7 @@ int rtrs_clt_create_path_from_sysfs(struct rtrs_clt *clt,
 	int err;
 
 	sess = alloc_sess(clt, addr, nr_cpu_ids, clt->max_segments,
-			  clt->max_segment_size);
+			  clt->max_segment_size, 0);
 	if (IS_ERR(sess))
 		return PTR_ERR(sess);
 
diff --git a/drivers/infiniband/ulp/rtrs/rtrs-pri.h b/drivers/infiniband/ulp/rtrs/rtrs-pri.h
index 8caad0a2322b..00eb45053339 100644
--- a/drivers/infiniband/ulp/rtrs/rtrs-pri.h
+++ b/drivers/infiniband/ulp/rtrs/rtrs-pri.h
@@ -101,6 +101,7 @@ struct rtrs_sess {
 	uuid_t			uuid;
 	struct rtrs_con	**con;
 	unsigned int		con_num;
+	unsigned int		irq_con_num;
 	unsigned int		recon_cnt;
 	struct rtrs_ib_dev	*dev;
 	int			dev_ref;
diff --git a/drivers/infiniband/ulp/rtrs/rtrs.h b/drivers/infiniband/ulp/rtrs/rtrs.h
index 2db1b5eb3ab0..eb050738cda1 100644
--- a/drivers/infiniband/ulp/rtrs/rtrs.h
+++ b/drivers/infiniband/ulp/rtrs/rtrs.h
@@ -59,7 +59,7 @@ struct rtrs_clt *rtrs_clt_open(struct rtrs_clt_ops *ops,
 				 size_t pdu_sz, u8 reconnect_delay_sec,
 				 u16 max_segments,
 				 size_t max_segment_size,
-				 s16 max_reconnect_attempts);
+			         s16 max_reconnect_attempts, u32 nr_poll_queues);
 
 void rtrs_clt_close(struct rtrs_clt *sess);
 
@@ -103,6 +103,7 @@ int rtrs_clt_request(int dir, struct rtrs_clt_req_ops *ops,
 		     struct rtrs_clt *sess, struct rtrs_permit *permit,
 		     const struct kvec *vec, size_t nr, size_t len,
 		     struct scatterlist *sg, unsigned int sg_cnt);
+int rtrs_clt_rdma_cq_direct(struct rtrs_clt *clt, unsigned int index);
 
 /**
  * rtrs_attrs - RTRS session attributes
-- 
2.25.1

[PATCHv2 for-next 19/24] Documentation/ABI/rnbd-clt: Add description for nr_poll_queues

[Gioh Kim]

describe how to set nr_poll_queues and enable the polling

Signed-off-by: Gioh Kim <gi-oh.kim@ionos.com>
---
 Documentation/ABI/testing/sysfs-block-rnbd        |  6 ++++++
 Documentation/ABI/testing/sysfs-class-rnbd-client | 13 +++++++++++++
 2 files changed, 19 insertions(+)

diff --git a/Documentation/ABI/testing/sysfs-block-rnbd b/Documentation/ABI/testing/sysfs-block-rnbd
index ec716e1c31a8..80b420b5d6b8 100644
--- a/Documentation/ABI/testing/sysfs-block-rnbd
+++ b/Documentation/ABI/testing/sysfs-block-rnbd
@@ -56,3 +56,9 @@ Date:		Feb 2020
 KernelVersion:	5.7
 Contact:	Jack Wang <jinpu.wang@cloud.ionos.com> Danil Kipnis <danil.kipnis@cloud.ionos.com>
 Description:	Remap the disconnected device if the session is not destroyed yet.
+
+What:		/sys/block/rnbd<N>/rnbd/nr_poll_queues
+Date:		Feb 2020
+KernelVersion:	5.7
+Contact:	Jack Wang <jinpu.wang@cloud.ionos.com> Danil Kipnis <danil.kipnis@cloud.ionos.com>
+Description:	Contains the number of poll-mode queues
diff --git a/Documentation/ABI/testing/sysfs-class-rnbd-client b/Documentation/ABI/testing/sysfs-class-rnbd-client
index 2aa05b3e348e..0b5997ab3365 100644
--- a/Documentation/ABI/testing/sysfs-class-rnbd-client
+++ b/Documentation/ABI/testing/sysfs-class-rnbd-client
@@ -85,6 +85,19 @@ Description:	Expected format is the following::
 
 		By default "rw" is used.
 
+		nr_poll_queues
+		  specifies the number of poll-mode queues. If the IO has HIPRI flag,
+		  the block-layer will send the IO via the poll-mode queue.
+		  For fast network and device the polling is faster than interrupt-base
+		  IO handling because it saves time for context switching, switching to
+		  another process, handling the interrupt and switching back to the
+		  issuing process.
+
+		  Set -1 if you want to set it as the number of CPUs
+		  By default rnbd client creates only irq-mode queues.
+
+		  NOTICE: MUST make a unique session for a device using the poll-mode queues.
+
 		Exit Codes:
 
 		If the device is already mapped it will fail with EEXIST. If the input
-- 
2.25.1

[PATCHv2 for-next 20/24] block/rnbd-srv: Remove unused arguments of rnbd_srv_rdma_ev

[Gioh Kim]

From: Gioh Kim <gi-oh.kim@cloud.ionos.com>

struct rtrs_srv is not used when handling rnbd_srv_rdma_ev messages, so
cleaned up
rdma_ev function pointer in rtrs_srv_ops also is changed.

Cc: Jason Gunthorpe <jgg@nvidia.com>
Cc: Leon Romanovsky <leonro@nvidia.com>
Cc: linux-rdma@vger.kernel.org
Signed-off-by: Aleksei Marov <aleksei.marov@ionos.com>
Signed-off-by: Jack Wang <jinpu.wang@ionos.com>
Signed-off-by: Gioh Kim <gi-oh.kim@ionos.com>
---
 drivers/block/rnbd/rnbd-srv.c          | 39 ++++++++++----------------
 drivers/infiniband/ulp/rtrs/rtrs-srv.c |  4 +--
 drivers/infiniband/ulp/rtrs/rtrs.h     |  3 +-
 3 files changed, 18 insertions(+), 28 deletions(-)

diff --git a/drivers/block/rnbd/rnbd-srv.c b/drivers/block/rnbd/rnbd-srv.c
index a71b6f7662f5..78bd0ce0ebf0 100644
--- a/drivers/block/rnbd/rnbd-srv.c
+++ b/drivers/block/rnbd/rnbd-srv.c
@@ -119,8 +119,7 @@ rnbd_get_sess_dev(int dev_id, struct rnbd_srv_session *srv_sess)
 	return sess_dev;
 }
 
-static int process_rdma(struct rtrs_srv *sess,
-			struct rnbd_srv_session *srv_sess,
+static int process_rdma(struct rnbd_srv_session *srv_sess,
 			struct rtrs_srv_op *id, void *data, u32 datalen,
 			const void *usr, size_t usrlen)
 {
@@ -350,8 +349,7 @@ void rnbd_srv_sess_dev_force_close(struct rnbd_srv_sess_dev *sess_dev,
 	mutex_unlock(&sess->lock);
 }
 
-static int process_msg_close(struct rtrs_srv *rtrs,
-			     struct rnbd_srv_session *srv_sess,
+static int process_msg_close(struct rnbd_srv_session *srv_sess,
 			     void *data, size_t datalen, const void *usr,
 			     size_t usrlen)
 {
@@ -370,20 +368,18 @@ static int process_msg_close(struct rtrs_srv *rtrs,
 	return 0;
 }
 
-static int process_msg_open(struct rtrs_srv *rtrs,
-			    struct rnbd_srv_session *srv_sess,
+static int process_msg_open(struct rnbd_srv_session *srv_sess,
 			    const void *msg, size_t len,
 			    void *data, size_t datalen);
 
-static int process_msg_sess_info(struct rtrs_srv *rtrs,
-				 struct rnbd_srv_session *srv_sess,
+static int process_msg_sess_info(struct rnbd_srv_session *srv_sess,
 				 const void *msg, size_t len,
 				 void *data, size_t datalen);
 
-static int rnbd_srv_rdma_ev(struct rtrs_srv *rtrs, void *priv,
-			     struct rtrs_srv_op *id, int dir,
-			     void *data, size_t datalen, const void *usr,
-			     size_t usrlen)
+static int rnbd_srv_rdma_ev(void *priv,
+			    struct rtrs_srv_op *id, int dir,
+			    void *data, size_t datalen, const void *usr,
+			    size_t usrlen)
 {
 	struct rnbd_srv_session *srv_sess = priv;
 	const struct rnbd_msg_hdr *hdr = usr;
@@ -397,19 +393,16 @@ static int rnbd_srv_rdma_ev(struct rtrs_srv *rtrs, void *priv,
 
 	switch (type) {
 	case RNBD_MSG_IO:
-		return process_rdma(rtrs, srv_sess, id, data, datalen, usr,
-				    usrlen);
+		return process_rdma(srv_sess, id, data, datalen, usr, usrlen);
 	case RNBD_MSG_CLOSE:
-		ret = process_msg_close(rtrs, srv_sess, data, datalen,
-					usr, usrlen);
+		ret = process_msg_close(srv_sess, data, datalen, usr, usrlen);
 		break;
 	case RNBD_MSG_OPEN:
-		ret = process_msg_open(rtrs, srv_sess, usr, usrlen,
-				       data, datalen);
+		ret = process_msg_open(srv_sess, usr, usrlen, data, datalen);
 		break;
 	case RNBD_MSG_SESS_INFO:
-		ret = process_msg_sess_info(rtrs, srv_sess, usr, usrlen,
-					    data, datalen);
+		ret = process_msg_sess_info(srv_sess, usr, usrlen, data,
+					    datalen);
 		break;
 	default:
 		pr_warn("Received unexpected message type %d with dir %d from session %s\n",
@@ -662,8 +655,7 @@ static char *rnbd_srv_get_full_path(struct rnbd_srv_session *srv_sess,
 	return full_path;
 }
 
-static int process_msg_sess_info(struct rtrs_srv *rtrs,
-				 struct rnbd_srv_session *srv_sess,
+static int process_msg_sess_info(struct rnbd_srv_session *srv_sess,
 				 const void *msg, size_t len,
 				 void *data, size_t datalen)
 {
@@ -704,8 +696,7 @@ find_srv_sess_dev(struct rnbd_srv_session *srv_sess, const char *dev_name)
 	return NULL;
 }
 
-static int process_msg_open(struct rtrs_srv *rtrs,
-			    struct rnbd_srv_session *srv_sess,
+static int process_msg_open(struct rnbd_srv_session *srv_sess,
 			    const void *msg, size_t len,
 			    void *data, size_t datalen)
 {
diff --git a/drivers/infiniband/ulp/rtrs/rtrs-srv.c b/drivers/infiniband/ulp/rtrs/rtrs-srv.c
index d071809e3ed2..f7aa2a7e7442 100644
--- a/drivers/infiniband/ulp/rtrs/rtrs-srv.c
+++ b/drivers/infiniband/ulp/rtrs/rtrs-srv.c
@@ -998,7 +998,7 @@ static void process_read(struct rtrs_srv_con *con,
 	usr_len = le16_to_cpu(msg->usr_len);
 	data_len = off - usr_len;
 	data = page_address(srv->chunks[buf_id]);
-	ret = ctx->ops.rdma_ev(srv, srv->priv, id, READ, data, data_len,
+	ret = ctx->ops.rdma_ev(srv->priv, id, READ, data, data_len,
 			   data + data_len, usr_len);
 
 	if (unlikely(ret)) {
@@ -1051,7 +1051,7 @@ static void process_write(struct rtrs_srv_con *con,
 	usr_len = le16_to_cpu(req->usr_len);
 	data_len = off - usr_len;
 	data = page_address(srv->chunks[buf_id]);
-	ret = ctx->ops.rdma_ev(srv, srv->priv, id, WRITE, data, data_len,
+	ret = ctx->ops.rdma_ev(srv->priv, id, WRITE, data, data_len,
 			   data + data_len, usr_len);
 	if (unlikely(ret)) {
 		rtrs_err_rl(s,
diff --git a/drivers/infiniband/ulp/rtrs/rtrs.h b/drivers/infiniband/ulp/rtrs/rtrs.h
index eb050738cda1..c25a0fd8a607 100644
--- a/drivers/infiniband/ulp/rtrs/rtrs.h
+++ b/drivers/infiniband/ulp/rtrs/rtrs.h
@@ -139,7 +139,6 @@ struct rtrs_srv_ops {
 	 *			message for the data transfer will be sent to
 	 *			the client.
 
-	 *	@sess:		Session
 	 *	@priv:		Private data set by rtrs_srv_set_sess_priv()
 	 *	@id:		internal RTRS operation id
 	 *	@dir:		READ/WRITE
@@ -153,7 +152,7 @@ struct rtrs_srv_ops {
 	 *	@usr:		The extra user message sent by the client (%vec)
 	 *	@usrlen:	Size of the user message
 	 */
-	int (*rdma_ev)(struct rtrs_srv *sess, void *priv,
+	int (*rdma_ev)(void *priv,
 		       struct rtrs_srv_op *id, int dir,
 		       void *data, size_t datalen, const void *usr,
 		       size_t usrlen);
-- 
2.25.1

Re: [PATCHv2 for-next 20/24] block/rnbd-srv: Remove unused arguments of rnbd_srv_rdma_ev

[Chaitanya Kulkarni]

On 3/30/21 00:41, Gioh Kim wrote:
> From: Gioh Kim <gi-oh.kim@cloud.ionos.com>
>
> struct rtrs_srv is not used when handling rnbd_srv_rdma_ev messages, so
> cleaned up
> rdma_ev function pointer in rtrs_srv_ops also is changed.
>
> Cc: Jason Gunthorpe <jgg@nvidia.com>
> Cc: Leon Romanovsky <leonro@nvidia.com>
> Cc: linux-rdma@vger.kernel.org
> Signed-off-by: Aleksei Marov <aleksei.marov@ionos.com>
> Signed-off-by: Jack Wang <jinpu.wang@ionos.com>
> Signed-off-by: Gioh Kim <gi-oh.kim@ionos.com>
> ---

Commit log could be :-

struct rtrs_srv is not used when handling rnbd_srv_rdma_ev messages, so
cleaned up rdma_ev function pointer in rtrs_srv_ops also is changed.

That can be done at the time of applying patch.

Looks good.

Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>

[PATCHv2 for-next 21/24] block/rnbd-clt: Generate kobject_uevent when the rnbd device state changes

[Gioh Kim]

From: Md Haris Iqbal <haris.iqbal@cloud.ionos.com>

When an RTRS session state changes, the transport layer generates an event
to RNBD. Then RNBD will change the state of the RNBD client device
accordingly.

This commit add kobject_uevent when the RNBD device state changes. With
this udev rules can be configured to react accordingly.

Signed-off-by: Md Haris Iqbal <haris.iqbal@ionos.com>
Signed-off-by: Jack Wang <jinpu.wang@ionos.com>
Signed-off-by: Gioh Kim <gi-oh.kim@ionos.com>
---
 drivers/block/rnbd/rnbd-clt-sysfs.c | 1 +
 drivers/block/rnbd/rnbd-clt.c       | 9 ++++++++-
 2 files changed, 9 insertions(+), 1 deletion(-)

diff --git a/drivers/block/rnbd/rnbd-clt-sysfs.c b/drivers/block/rnbd/rnbd-clt-sysfs.c
index 9ea4da7f894a..630351574d1b 100644
--- a/drivers/block/rnbd/rnbd-clt-sysfs.c
+++ b/drivers/block/rnbd/rnbd-clt-sysfs.c
@@ -491,6 +491,7 @@ static int rnbd_clt_add_dev_kobj(struct rnbd_clt_dev *dev)
 			      ret);
 		kobject_put(&dev->kobj);
 	}
+	kobject_uevent(gd_kobj, KOBJ_ONLINE);
 
 	return ret;
 }
diff --git a/drivers/block/rnbd/rnbd-clt.c b/drivers/block/rnbd/rnbd-clt.c
index 998cadd73d47..6f3ca2e3bc02 100644
--- a/drivers/block/rnbd/rnbd-clt.c
+++ b/drivers/block/rnbd/rnbd-clt.c
@@ -110,6 +110,7 @@ static int rnbd_clt_change_capacity(struct rnbd_clt_dev *dev,
 static int process_msg_open_rsp(struct rnbd_clt_dev *dev,
 				struct rnbd_msg_open_rsp *rsp)
 {
+	struct kobject *gd_kobj;
 	int err = 0;
 
 	mutex_lock(&dev->lock);
@@ -128,6 +129,8 @@ static int process_msg_open_rsp(struct rnbd_clt_dev *dev,
 		 */
 		if (dev->nsectors != nsectors)
 			rnbd_clt_change_capacity(dev, nsectors);
+		gd_kobj = &disk_to_dev(dev->gd)->kobj;
+		kobject_uevent(gd_kobj, KOBJ_ONLINE);
 		rnbd_clt_info(dev, "Device online, device remapped successfully\n");
 	}
 	err = rnbd_clt_set_dev_attr(dev, rsp);
@@ -654,14 +657,18 @@ static int send_msg_sess_info(struct rnbd_clt_session *sess, enum wait_type wait
 static void set_dev_states_to_disconnected(struct rnbd_clt_session *sess)
 {
 	struct rnbd_clt_dev *dev;
+	struct kobject *gd_kobj;
 
 	mutex_lock(&sess->lock);
 	list_for_each_entry(dev, &sess->devs_list, list) {
 		rnbd_clt_err(dev, "Device disconnected.\n");
 
 		mutex_lock(&dev->lock);
-		if (dev->dev_state == DEV_STATE_MAPPED)
+		if (dev->dev_state == DEV_STATE_MAPPED) {
 			dev->dev_state = DEV_STATE_MAPPED_DISCONNECTED;
+			gd_kobj = &disk_to_dev(dev->gd)->kobj;
+			kobject_uevent(gd_kobj, KOBJ_OFFLINE);
+		}
 		mutex_unlock(&dev->lock);
 	}
 	mutex_unlock(&sess->lock);
-- 
2.25.1

[PATCHv2 for-next 22/24] block/rnbd-clt: Remove max_segment_size

[Gioh Kim]

From: Jack Wang <jinpu.wang@cloud.ionos.com>

We always map with SZ_4K, so do not need max_segment_size.

Cc: Jason Gunthorpe <jgg@mellanox.com>
Cc: Leon Romanovsky <leonro@nvidia.com>
Cc: linux-rdma@vger.kernel.org
Signed-off-by: Jack Wang <jinpu.wang@ionos.com>
Reviewed-by: Md Haris Iqbal <haris.iqbal@ionos.com>
Signed-off-by: Gioh Kim <gi-oh.kim@ionos.com>
---
 drivers/block/rnbd/rnbd-clt.c          |  1 -
 drivers/infiniband/ulp/rtrs/rtrs-clt.c | 15 +++++----------
 drivers/infiniband/ulp/rtrs/rtrs-clt.h |  1 -
 drivers/infiniband/ulp/rtrs/rtrs.h     |  1 -
 4 files changed, 5 insertions(+), 13 deletions(-)

diff --git a/drivers/block/rnbd/rnbd-clt.c b/drivers/block/rnbd/rnbd-clt.c
index 6f3ca2e3bc02..9d1bc49d5595 100644
--- a/drivers/block/rnbd/rnbd-clt.c
+++ b/drivers/block/rnbd/rnbd-clt.c
@@ -1295,7 +1295,6 @@ find_and_get_or_create_sess(const char *sessname,
 				   paths, path_cnt, port_nr,
 				   0, /* Do not use pdu of rtrs */
 				   RECONNECT_DELAY, BMAX_SEGMENTS,
-				   BLK_MAX_SEGMENT_SIZE,
 				   MAX_RECONNECTS, nr_poll_queues);
 	if (IS_ERR(sess->rtrs)) {
 		err = PTR_ERR(sess->rtrs);
diff --git a/drivers/infiniband/ulp/rtrs/rtrs-clt.c b/drivers/infiniband/ulp/rtrs/rtrs-clt.c
index cf9dbcbc11e7..db15257dc978 100644
--- a/drivers/infiniband/ulp/rtrs/rtrs-clt.c
+++ b/drivers/infiniband/ulp/rtrs/rtrs-clt.c
@@ -1400,7 +1400,7 @@ static void rtrs_clt_close_work(struct work_struct *work);
 static struct rtrs_clt_sess *alloc_sess(struct rtrs_clt *clt,
 					 const struct rtrs_addr *path,
 					 size_t con_num, u16 max_segments,
-					 size_t max_segment_size, u32 nr_poll_queues)
+					 u32 nr_poll_queues)
 {
 	struct rtrs_clt_sess *sess;
 	int err = -ENOMEM;
@@ -1442,7 +1442,7 @@ static struct rtrs_clt_sess *alloc_sess(struct rtrs_clt *clt,
 		       rdma_addr_size((struct sockaddr *)path->src));
 	strlcpy(sess->s.sessname, clt->sessname, sizeof(sess->s.sessname));
 	sess->clt = clt;
-	sess->max_pages_per_mr = max_segments * max_segment_size >> 12;
+	sess->max_pages_per_mr = max_segments;
 	init_waitqueue_head(&sess->state_wq);
 	sess->state = RTRS_CLT_CONNECTING;
 	atomic_set(&sess->connected_cnt, 0);
@@ -2538,7 +2538,6 @@ static struct rtrs_clt *alloc_clt(const char *sessname, size_t paths_num,
 				  void	(*link_ev)(void *priv,
 						   enum rtrs_clt_link_ev ev),
 				  unsigned int max_segments,
-				  size_t max_segment_size,
 				  unsigned int reconnect_delay_sec,
 				  unsigned int max_reconnect_attempts)
 {
@@ -2568,7 +2567,6 @@ static struct rtrs_clt *alloc_clt(const char *sessname, size_t paths_num,
 	clt->port = port;
 	clt->pdu_sz = pdu_sz;
 	clt->max_segments = max_segments;
-	clt->max_segment_size = max_segment_size;
 	clt->reconnect_delay_sec = reconnect_delay_sec;
 	clt->max_reconnect_attempts = max_reconnect_attempts;
 	clt->priv = priv;
@@ -2638,7 +2636,6 @@ static void free_clt(struct rtrs_clt *clt)
  * @pdu_sz: Size of extra payload which can be accessed after permit allocation.
  * @reconnect_delay_sec: time between reconnect tries
  * @max_segments: Max. number of segments per IO request
- * @max_segment_size: Max. size of one segment
  * @max_reconnect_attempts: Number of times to reconnect on error before giving
  *			    up, 0 for * disabled, -1 for forever
  * @nr_poll_queues: number of polling mode connection using IB_POLL_DIRECT flag
@@ -2654,7 +2651,6 @@ struct rtrs_clt *rtrs_clt_open(struct rtrs_clt_ops *ops,
 				 size_t paths_num, u16 port,
 				 size_t pdu_sz, u8 reconnect_delay_sec,
 				 u16 max_segments,
-				 size_t max_segment_size,
 			         s16 max_reconnect_attempts, u32 nr_poll_queues)
 {
 	struct rtrs_clt_sess *sess, *tmp;
@@ -2663,7 +2659,7 @@ struct rtrs_clt *rtrs_clt_open(struct rtrs_clt_ops *ops,
 
 	clt = alloc_clt(sessname, paths_num, port, pdu_sz, ops->priv,
 			ops->link_ev,
-			max_segments, max_segment_size, reconnect_delay_sec,
+			max_segments, reconnect_delay_sec,
 			max_reconnect_attempts);
 	if (IS_ERR(clt)) {
 		err = PTR_ERR(clt);
@@ -2673,7 +2669,7 @@ struct rtrs_clt *rtrs_clt_open(struct rtrs_clt_ops *ops,
 		struct rtrs_clt_sess *sess;
 
 		sess = alloc_sess(clt, &paths[i], nr_cpu_ids,
-				  max_segments, max_segment_size, nr_poll_queues);
+				  max_segments, nr_poll_queues);
 		if (IS_ERR(sess)) {
 			err = PTR_ERR(sess);
 			goto close_all_sess;
@@ -2951,8 +2947,7 @@ int rtrs_clt_create_path_from_sysfs(struct rtrs_clt *clt,
 	struct rtrs_clt_sess *sess;
 	int err;
 
-	sess = alloc_sess(clt, addr, nr_cpu_ids, clt->max_segments,
-			  clt->max_segment_size, 0);
+	sess = alloc_sess(clt, addr, nr_cpu_ids, clt->max_segments, 0);
 	if (IS_ERR(sess))
 		return PTR_ERR(sess);
 
diff --git a/drivers/infiniband/ulp/rtrs/rtrs-clt.h b/drivers/infiniband/ulp/rtrs/rtrs-clt.h
index 692bc83e1f09..98ba5d0a48b8 100644
--- a/drivers/infiniband/ulp/rtrs/rtrs-clt.h
+++ b/drivers/infiniband/ulp/rtrs/rtrs-clt.h
@@ -166,7 +166,6 @@ struct rtrs_clt {
 	unsigned int		max_reconnect_attempts;
 	unsigned int		reconnect_delay_sec;
 	unsigned int		max_segments;
-	size_t			max_segment_size;
 	void			*permits;
 	unsigned long		*permits_map;
 	size_t			queue_depth;
diff --git a/drivers/infiniband/ulp/rtrs/rtrs.h b/drivers/infiniband/ulp/rtrs/rtrs.h
index c25a0fd8a607..feb76af95e96 100644
--- a/drivers/infiniband/ulp/rtrs/rtrs.h
+++ b/drivers/infiniband/ulp/rtrs/rtrs.h
@@ -58,7 +58,6 @@ struct rtrs_clt *rtrs_clt_open(struct rtrs_clt_ops *ops,
 				 size_t path_cnt, u16 port,
 				 size_t pdu_sz, u8 reconnect_delay_sec,
 				 u16 max_segments,
-				 size_t max_segment_size,
 			         s16 max_reconnect_attempts, u32 nr_poll_queues);
 
 void rtrs_clt_close(struct rtrs_clt *sess);
-- 
2.25.1

[PATCHv2 for-next 23/24] block/rnbd-clt-sysfs: Remove copy buffer overlap in rnbd_clt_get_path_name

[Gioh Kim]

From: Dima Stepanov <dmitrii.stepanov@cloud.ionos.com>

cppcheck report the following error:
  rnbd/rnbd-clt-sysfs.c:522:36: error: The variable 'buf' is used both
  as a parameter and as destination in snprintf(). The origin and
  destination buffers overlap. Quote from glibc (C-library)
  documentation
  (http://www.gnu.org/software/libc/manual/html_mono/libc.html#Formatted-Output-Functions):
  "If copying takes place between objects that overlap as a result of a
  call to sprintf() or snprintf(), the results are undefined."
  [sprintfOverlappingData]
Fix it by initializing the buf variable in the first snprintf call.

Fixes: 91f4acb2801c ("block/rnbd-clt: support mapping two devices")
Signed-off-by: Dima Stepanov <dmitrii.stepanov@ionos.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Jack Wang <jinpu.wang@ionos.com>
---
 drivers/block/rnbd/rnbd-clt-sysfs.c | 6 +-----
 1 file changed, 1 insertion(+), 5 deletions(-)

diff --git a/drivers/block/rnbd/rnbd-clt-sysfs.c b/drivers/block/rnbd/rnbd-clt-sysfs.c
index 630351574d1b..b1d04115e049 100644
--- a/drivers/block/rnbd/rnbd-clt-sysfs.c
+++ b/drivers/block/rnbd/rnbd-clt-sysfs.c
@@ -515,11 +515,7 @@ static int rnbd_clt_get_path_name(struct rnbd_clt_dev *dev, char *buf,
 	while ((s = strchr(pathname, '/')))
 		s[0] = '!';
 
-	ret = snprintf(buf, len, "%s", pathname);
-	if (ret >= len)
-		return -ENAMETOOLONG;
-
-	ret = snprintf(buf, len, "%s@%s", buf, dev->sess->sessname);
+	ret = snprintf(buf, len, "%s@%s", pathname, dev->sess->sessname);
 	if (ret >= len)
 		return -ENAMETOOLONG;
 
-- 
2.25.1

Re: [PATCHv2 for-next 23/24] block/rnbd-clt-sysfs: Remove copy buffer overlap in rnbd_clt_get_path_name

[Chaitanya Kulkarni]

On 3/30/21 00:41, Gioh Kim wrote:
> From: Dima Stepanov <dmitrii.stepanov@cloud.ionos.com>
>
> cppcheck report the following error:
>   rnbd/rnbd-clt-sysfs.c:522:36: error: The variable 'buf' is used both
>   as a parameter and as destination in snprintf(). The origin and
>   destination buffers overlap. Quote from glibc (C-library)
>   documentation
>   (http://www.gnu.org/software/libc/manual/html_mono/libc.html#Formatted-Output-Functions):
>   "If copying takes place between objects that overlap as a result of a
>   call to sprintf() or snprintf(), the results are undefined."
>   [sprintfOverlappingData]
> Fix it by initializing the buf variable in the first snprintf call.
>
> Fixes: 91f4acb2801c ("block/rnbd-clt: support mapping two devices")
> Signed-off-by: Dima Stepanov <dmitrii.stepanov@ionos.com>
> Cc: Arnd Bergmann <arnd@arndb.de>
> Signed-off-by: Jack Wang <jinpu.wang@ionos.com>

Looks good.

Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>

[PATCHv2 for-next 24/24] block/rnbd: Use strscpy instead of strlcpy

[Gioh Kim]

From: Dima Stepanov <dmitrii.stepanov@cloud.ionos.com>

During checkpatch analyzing the following warning message was found:
  WARNING:STRLCPY: Prefer strscpy over strlcpy - see:
  https://lore.kernel.org/r/CAHk-=wgfRnXz0W3D37d01q3JFkr_i_uTL=V6A6G1oUZcprmknw@mail.gmail.com/
Fix it by using strscpy calls instead of strlcpy.

Signed-off-by: Dima Stepanov <dmitrii.stepanov@cloud.ionos.com>
Signed-off-by: Jack Wang <jinpu.wang@ionos.com>
---
 drivers/block/rnbd/rnbd-clt-sysfs.c | 6 +++---
 drivers/block/rnbd/rnbd-clt.c       | 4 ++--
 drivers/block/rnbd/rnbd-srv.c       | 6 +++---
 3 files changed, 8 insertions(+), 8 deletions(-)

diff --git a/drivers/block/rnbd/rnbd-clt-sysfs.c b/drivers/block/rnbd/rnbd-clt-sysfs.c
index b1d04115e049..3c3172af08da 100644
--- a/drivers/block/rnbd/rnbd-clt-sysfs.c
+++ b/drivers/block/rnbd/rnbd-clt-sysfs.c
@@ -99,7 +99,7 @@ static int rnbd_clt_parse_map_options(const char *buf, size_t max_path_cnt,
 				kfree(p);
 				goto out;
 			}
-			strlcpy(opt->sessname, p, NAME_MAX);
+			strscpy(opt->sessname, p, NAME_MAX);
 			kfree(p);
 			break;
 
@@ -142,7 +142,7 @@ static int rnbd_clt_parse_map_options(const char *buf, size_t max_path_cnt,
 				kfree(p);
 				goto out;
 			}
-			strlcpy(opt->pathname, p, NAME_MAX);
+			strscpy(opt->pathname, p, NAME_MAX);
 			kfree(p);
 			break;
 
@@ -511,7 +511,7 @@ static int rnbd_clt_get_path_name(struct rnbd_clt_dev *dev, char *buf,
 	int ret;
 	char pathname[NAME_MAX], *s;
 
-	strlcpy(pathname, dev->pathname, sizeof(pathname));
+	strscpy(pathname, dev->pathname, sizeof(pathname));
 	while ((s = strchr(pathname, '/')))
 		s[0] = '!';
 
diff --git a/drivers/block/rnbd/rnbd-clt.c b/drivers/block/rnbd/rnbd-clt.c
index 9d1bc49d5595..6e5d4a02a9b7 100644
--- a/drivers/block/rnbd/rnbd-clt.c
+++ b/drivers/block/rnbd/rnbd-clt.c
@@ -583,7 +583,7 @@ static int send_msg_open(struct rnbd_clt_dev *dev, enum wait_type wait)
 
 	msg.hdr.type	= cpu_to_le16(RNBD_MSG_OPEN);
 	msg.access_mode	= dev->access_mode;
-	strlcpy(msg.dev_name, dev->pathname, sizeof(msg.dev_name));
+	strscpy(msg.dev_name, dev->pathname, sizeof(msg.dev_name));
 
 	WARN_ON(!rnbd_clt_get_dev(dev));
 	err = send_usr_msg(sess->rtrs, READ, iu,
@@ -805,7 +805,7 @@ static struct rnbd_clt_session *alloc_sess(const char *sessname)
 	sess = kzalloc_node(sizeof(*sess), GFP_KERNEL, NUMA_NO_NODE);
 	if (!sess)
 		return ERR_PTR(-ENOMEM);
-	strlcpy(sess->sessname, sessname, sizeof(sess->sessname));
+	strscpy(sess->sessname, sessname, sizeof(sess->sessname));
 	atomic_set(&sess->busy, 0);
 	mutex_init(&sess->lock);
 	INIT_LIST_HEAD(&sess->devs_list);
diff --git a/drivers/block/rnbd/rnbd-srv.c b/drivers/block/rnbd/rnbd-srv.c
index 78bd0ce0ebf0..d6ec16d7211d 100644
--- a/drivers/block/rnbd/rnbd-srv.c
+++ b/drivers/block/rnbd/rnbd-srv.c
@@ -304,7 +304,7 @@ static int create_sess(struct rtrs_srv *rtrs)
 	mutex_unlock(&sess_lock);
 
 	srv_sess->rtrs = rtrs;
-	strlcpy(srv_sess->sessname, sessname, sizeof(srv_sess->sessname));
+	strscpy(srv_sess->sessname, sessname, sizeof(srv_sess->sessname));
 
 	rtrs_srv_set_sess_priv(rtrs, srv_sess);
 
@@ -443,7 +443,7 @@ static struct rnbd_srv_dev *rnbd_srv_init_srv_dev(const char *id)
 	if (!dev)
 		return ERR_PTR(-ENOMEM);
 
-	strlcpy(dev->id, id, sizeof(dev->id));
+	strscpy(dev->id, id, sizeof(dev->id));
 	kref_init(&dev->kref);
 	INIT_LIST_HEAD(&dev->sess_dev_list);
 	mutex_init(&dev->lock);
@@ -595,7 +595,7 @@ rnbd_srv_create_set_sess_dev(struct rnbd_srv_session *srv_sess,
 
 	kref_init(&sdev->kref);
 
-	strlcpy(sdev->pathname, open_msg->dev_name, sizeof(sdev->pathname));
+	strscpy(sdev->pathname, open_msg->dev_name, sizeof(sdev->pathname));
 
 	sdev->rnbd_dev		= rnbd_dev;
 	sdev->sess		= srv_sess;
-- 
2.25.1

Re: [PATCHv2 for-next 24/24] block/rnbd: Use strscpy instead of strlcpy

[Chaitanya Kulkarni]

On 3/30/21 00:41, Gioh Kim wrote:
> From: Dima Stepanov <dmitrii.stepanov@cloud.ionos.com>
>
> During checkpatch analyzing the following warning message was found:
>   WARNING:STRLCPY: Prefer strscpy over strlcpy - see:
>   https://lore.kernel.org/r/CAHk-=wgfRnXz0W3D37d01q3JFkr_i_uTL=V6A6G1oUZcprmknw@mail.gmail.com/
> Fix it by using strscpy calls instead of strlcpy.
>
> Signed-off-by: Dima Stepanov <dmitrii.stepanov@cloud.ionos.com>
> Signed-off-by: Jack Wang <jinpu.wang@ionos.com>

Looks good.

Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>

Re: [PATCHv2 for-next 00/24] Misc update for rnbd

[Jason Gunthorpe]

On Tue, Mar 30, 2021 at 09:37:28AM +0200, Gioh Kim wrote:
 
>  Documentation/ABI/testing/sysfs-block-rnbd    |  18 ++
>  .../ABI/testing/sysfs-class-rnbd-client       |  13 ++
>  Documentation/fault-injection/index.rst       |   2 +
>  .../fault-injection/rnbd-fault-injection.rst  | 208 ++++++++++++++++++
>  MAINTAINERS                                   |   4 +-
>  drivers/block/rnbd/rnbd-clt-sysfs.c           | 138 +++++++++---
>  drivers/block/rnbd/rnbd-clt.c                 | 184 +++++++++++-----
>  drivers/block/rnbd/rnbd-clt.h                 |  21 +-
>  drivers/block/rnbd/rnbd-common.c              |  44 ++++
>  drivers/block/rnbd/rnbd-proto.h               |  14 ++
>  drivers/block/rnbd/rnbd-srv-sysfs.c           |  41 +++-
>  drivers/block/rnbd/rnbd-srv.c                 |  76 +++----
>  drivers/block/rnbd/rnbd-srv.h                 |  16 +-
>  drivers/infiniband/ulp/rtrs/rtrs-clt.c        |  75 +++++--
>  drivers/infiniband/ulp/rtrs/rtrs-clt.h        |   1 -
>  drivers/infiniband/ulp/rtrs/rtrs-pri.h        |   1 +
>  drivers/infiniband/ulp/rtrs/rtrs-srv.c        |   4 +-
>  drivers/infiniband/ulp/rtrs/rtrs.h            |  13 +-

I did not see anything to comment on in the drivers/infiniband part,
so you can have an

Acked-by: Jason Gunthorpe <jgg@nvidia.com>

To flow through the block tree.

*However* do not create merge conflicts with the patches you already
sent to the rdma tree. It is Ionos's responsibility to prevent this.

Jason