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[v9,03/25] RDMA/rtrs: private headers with rtrs protocol structs and helpers

Message ID 20200221104721.350-4-jinpuwang@gmail.com (mailing list archive)
State New, archived
Headers show
Series RTRS (former IBTRS) RDMA Transport Library and RNBD (former IBNBD) RDMA Network Block Device | expand

Commit Message

Jinpu Wang Feb. 21, 2020, 10:46 a.m. UTC 
From: Jack Wang <jinpu.wang@cloud.ionos.com>

These are common private headers with rtrs protocol structures,
logging, sysfs and other helper functions, which are used on
both client and server sides.

Signed-off-by: Danil Kipnis <danil.kipnis@cloud.ionos.com>
Signed-off-by: Jack Wang <jinpu.wang@cloud.ionos.com>
---
 drivers/infiniband/ulp/rtrs/rtrs-log.h |  28 ++
 drivers/infiniband/ulp/rtrs/rtrs-pri.h | 401 +++++++++++++++++++++++++
 2 files changed, 429 insertions(+)
 create mode 100644 drivers/infiniband/ulp/rtrs/rtrs-log.h
 create mode 100644 drivers/infiniband/ulp/rtrs/rtrs-pri.h

Comments

Bart Van Assche March 1, 2020, 12:37 a.m. UTC | #1 
On 2020-02-21 02:46, Jack Wang wrote:
> +enum rtrs_imm_type {
> +	RTRS_IO_REQ_IMM       = 0, /* client to server */
> +	RTRS_IO_RSP_IMM       = 1, /* server to client */
> +	RTRS_IO_RSP_W_INV_IMM = 2, /* server to client */
> +
> +	RTRS_HB_MSG_IMM = 8,
> +	RTRS_HB_ACK_IMM = 9,
> +
> +	RTRS_LAST_IMM,
> +};

This is the first time in this header file that the abbreviation "hb" is
used. Please add a comment that explains what this abbreviation stands for.

Thanks,

Bart.
Jinpu Wang March 2, 2020, 9:21 a.m. UTC | #2 
On Sun, Mar 1, 2020 at 1:37 AM Bart Van Assche <bvanassche@acm.org> wrote:
>
> On 2020-02-21 02:46, Jack Wang wrote:
> > +enum rtrs_imm_type {
> > +     RTRS_IO_REQ_IMM       = 0, /* client to server */
> > +     RTRS_IO_RSP_IMM       = 1, /* server to client */
> > +     RTRS_IO_RSP_W_INV_IMM = 2, /* server to client */
> > +
> > +     RTRS_HB_MSG_IMM = 8, /* HB: HeartBeat */
> > +     RTRS_HB_ACK_IMM = 9,
> > +
> > +     RTRS_LAST_IMM,
> > +};
>
> This is the first time in this header file that the abbreviation "hb" is
> used. Please add a comment that explains what this abbreviation stands for.
>
> Thanks,
>
> Bart.
Will do, thank you
Leon Romanovsky March 3, 2020, 9:45 a.m. UTC | #3 
On Fri, Feb 21, 2020 at 11:46:59AM +0100, Jack Wang wrote:
> From: Jack Wang <jinpu.wang@cloud.ionos.com>
>
> These are common private headers with rtrs protocol structures,
> logging, sysfs and other helper functions, which are used on
> both client and server sides.
>
> Signed-off-by: Danil Kipnis <danil.kipnis@cloud.ionos.com>
> Signed-off-by: Jack Wang <jinpu.wang@cloud.ionos.com>
> ---
>  drivers/infiniband/ulp/rtrs/rtrs-log.h |  28 ++
>  drivers/infiniband/ulp/rtrs/rtrs-pri.h | 401 +++++++++++++++++++++++++
>  2 files changed, 429 insertions(+)
>  create mode 100644 drivers/infiniband/ulp/rtrs/rtrs-log.h
>  create mode 100644 drivers/infiniband/ulp/rtrs/rtrs-pri.h
>
> diff --git a/drivers/infiniband/ulp/rtrs/rtrs-log.h b/drivers/infiniband/ulp/rtrs/rtrs-log.h
> new file mode 100644
> index 000000000000..53c785b992f2
> --- /dev/null
> +++ b/drivers/infiniband/ulp/rtrs/rtrs-log.h
> @@ -0,0 +1,28 @@
> +/* SPDX-License-Identifier: GPL-2.0-or-later */
> +/*
> + * RDMA Transport Layer
> + *
> + * Copyright (c) 2014 - 2018 ProfitBricks GmbH. All rights reserved.
> + * Copyright (c) 2018 - 2019 1&1 IONOS Cloud GmbH. All rights reserved.
> + * Copyright (c) 2019 - 2020 1&1 IONOS SE. All rights reserved.
> + */
> +#ifndef RTRS_LOG_H
> +#define RTRS_LOG_H
> +
> +#define rtrs_log(fn, obj, fmt, ...)				\
> +	fn("<%s>: " fmt, obj->sessname, ##__VA_ARGS__)
> +
> +#define rtrs_err(obj, fmt, ...)	\
> +	rtrs_log(pr_err, obj, fmt, ##__VA_ARGS__)
> +#define rtrs_err_rl(obj, fmt, ...)	\
> +	rtrs_log(pr_err_ratelimited, obj, fmt, ##__VA_ARGS__)
> +#define rtrs_wrn(obj, fmt, ...)	\
> +	rtrs_log(pr_warn, obj, fmt, ##__VA_ARGS__)
> +#define rtrs_wrn_rl(obj, fmt, ...) \
> +	rtrs_log(pr_warn_ratelimited, obj, fmt, ##__VA_ARGS__)
> +#define rtrs_info(obj, fmt, ...) \
> +	rtrs_log(pr_info, obj, fmt, ##__VA_ARGS__)
> +#define rtrs_info_rl(obj, fmt, ...) \
> +	rtrs_log(pr_info_ratelimited, obj, fmt, ##__VA_ARGS__)
> +
> +#endif /* RTRS_LOG_H */
> diff --git a/drivers/infiniband/ulp/rtrs/rtrs-pri.h b/drivers/infiniband/ulp/rtrs/rtrs-pri.h
> new file mode 100644
> index 000000000000..aecf01a7d8dc
> --- /dev/null
> +++ b/drivers/infiniband/ulp/rtrs/rtrs-pri.h
> @@ -0,0 +1,401 @@
> +/* SPDX-License-Identifier: GPL-2.0-or-later */
> +/*
> + * RDMA Transport Layer
> + *
> + * Copyright (c) 2014 - 2018 ProfitBricks GmbH. All rights reserved.
> + * Copyright (c) 2018 - 2019 1&1 IONOS Cloud GmbH. All rights reserved.
> + * Copyright (c) 2019 - 2020 1&1 IONOS SE. All rights reserved.
> + */
> +
> +#ifndef RTRS_PRI_H
> +#define RTRS_PRI_H
> +
> +#include <linux/uuid.h>
> +#include <rdma/rdma_cm.h>
> +#include <rdma/ib_verbs.h>
> +#include <rdma/ib.h>
> +
> +#include "rtrs.h"
> +
> +#define RTRS_PROTO_VER_MAJOR 2
> +#define RTRS_PROTO_VER_MINOR 0

I think that Jason once said that new submission starts from "1".
There is no RTRS_PROTO_VER_MAJOR == 1 in the wild.

> +
> +#define RTRS_PROTO_VER_STRING __stringify(RTRS_PROTO_VER_MAJOR) "." \
> +			       __stringify(RTRS_PROTO_VER_MINOR)
> +
> +enum rtrs_imm_const {
> +	MAX_IMM_TYPE_BITS = 4,
> +	MAX_IMM_TYPE_MASK = ((1 << MAX_IMM_TYPE_BITS) - 1),
> +	MAX_IMM_PAYL_BITS = 28,
> +	MAX_IMM_PAYL_MASK = ((1 << MAX_IMM_PAYL_BITS) - 1),
> +};
> +
> +enum rtrs_imm_type {
> +	RTRS_IO_REQ_IMM       = 0, /* client to server */
> +	RTRS_IO_RSP_IMM       = 1, /* server to client */
> +	RTRS_IO_RSP_W_INV_IMM = 2, /* server to client */
> +
> +	RTRS_HB_MSG_IMM = 8,
> +	RTRS_HB_ACK_IMM = 9,
> +
> +	RTRS_LAST_IMM,
> +};
> +
> +enum {
> +	SERVICE_CON_QUEUE_DEPTH = 512,
> +
> +	MAX_PATHS_NUM = 128,
> +
> +	/*
> +	 * With the size of struct rtrs_permit allocated on the client, 4K
> +	 * is the maximum number of rtrs_permits we can allocate. This number is
> +	 * also used on the client to allocate the IU for the user connection
> +	 * to receive the RDMA addresses from the server.
> +	 */
> +	MAX_SESS_QUEUE_DEPTH = 4096,
> +
> +	RTRS_HB_INTERVAL_MS = 5000,
> +	RTRS_HB_MISSED_MAX = 5,
> +
> +	RTRS_MAGIC = 0x1BBD,
> +	RTRS_PROTO_VER = (RTRS_PROTO_VER_MAJOR << 8) | RTRS_PROTO_VER_MINOR,
> +};
> +
> +struct rtrs_ib_dev;
> +
> +struct rtrs_rdma_dev_pd_ops {
> +	struct rtrs_ib_dev *(*alloc)(void);
> +	void (*free)(struct rtrs_ib_dev *dev);
> +	int (*init)(struct rtrs_ib_dev *dev);
> +	void (*deinit)(struct rtrs_ib_dev *dev);
> +};
> +
> +struct rtrs_rdma_dev_pd {
> +	struct mutex		mutex;
> +	struct list_head	list;
> +	enum ib_pd_flags	pd_flags;
> +	const struct rtrs_rdma_dev_pd_ops *ops;
> +};
> +
> +struct rtrs_ib_dev {
> +	struct ib_device	 *ib_dev;
> +	struct ib_pd		 *ib_pd;
> +	struct kref		 ref;
> +	struct list_head	 entry;
> +	struct rtrs_rdma_dev_pd *pool;
> +};
> +
> +struct rtrs_con {
> +	struct rtrs_sess	*sess;
> +	struct ib_qp		*qp;
> +	struct ib_cq		*cq;
> +	struct rdma_cm_id	*cm_id;
> +	unsigned int		cid;
> +};
> +
> +typedef void (rtrs_hb_handler_t)(struct rtrs_con *con);
> +
> +struct rtrs_sess {
> +	struct list_head	entry;
> +	struct sockaddr_storage dst_addr;
> +	struct sockaddr_storage src_addr;
> +	char			sessname[NAME_MAX];
> +	uuid_t			uuid;
> +	struct rtrs_con	**con;
> +	unsigned int		con_num;
> +	unsigned int		recon_cnt;
> +	struct rtrs_ib_dev	*dev;
> +	int			dev_ref;
> +	struct ib_cqe		*hb_cqe;
> +	rtrs_hb_handler_t	*hb_err_handler;
> +	struct workqueue_struct *hb_wq;
> +	struct delayed_work	hb_dwork;
> +	unsigned int		hb_interval_ms;
> +	unsigned int		hb_missed_cnt;
> +	unsigned int		hb_missed_max;
> +};
> +
> +/* rtrs information unit */
> +struct rtrs_iu {
> +	struct list_head        list;
> +	struct ib_cqe           cqe;
> +	dma_addr_t              dma_addr;
> +	void                    *buf;
> +	size_t                  size;
> +	enum dma_data_direction direction;
> +};
> +
> +/**
> + * enum rtrs_msg_types - RTRS message types, see also rtrs/README
> + * @RTRS_MSG_INFO_REQ:		Client additional info request to the server
> + * @RTRS_MSG_INFO_RSP:		Server additional info response to the client
> + * @RTRS_MSG_WRITE:		Client writes data per RDMA to server
> + * @RTRS_MSG_READ:		Client requests data transfer from server
> + * @RTRS_MSG_RKEY_RSP:		Server refreshed rkey for rbuf
> + */
> +enum rtrs_msg_types {
> +	RTRS_MSG_INFO_REQ,
> +	RTRS_MSG_INFO_RSP,
> +	RTRS_MSG_WRITE,
> +	RTRS_MSG_READ,
> +	RTRS_MSG_RKEY_RSP,
> +};
> +
> +/**
> + * enum rtrs_msg_flags - RTRS message flags.
> + * @RTRS_NEED_INVAL:	Send invalidation in response.
> + * @RTRS_MSG_NEW_RKEY_F: Send refreshed rkey in response.
> + */
> +enum rtrs_msg_flags {
> +	RTRS_MSG_NEED_INVAL_F = 1 << 0,
> +	RTRS_MSG_NEW_RKEY_F = 1 << 1,
> +};
> +
> +/**
> + * struct rtrs_sg_desc - RDMA-Buffer entry description
> + * @addr:	Address of RDMA destination buffer
> + * @key:	Authorization rkey to write to the buffer
> + * @len:	Size of the buffer
> + */
> +struct rtrs_sg_desc {
> +	__le64			addr;
> +	__le32			key;
> +	__le32			len;
> +};
> +
> +/**
> + * struct rtrs_msg_conn_req - Client connection request to the server
> + * @magic:	   RTRS magic
> + * @version:	   RTRS protocol version
> + * @cid:	   Current connection id
> + * @cid_num:	   Number of connections per session
> + * @recon_cnt:	   Reconnections counter
> + * @sess_uuid:	   UUID of a session (path)
> + * @paths_uuid:	   UUID of a group of sessions (paths)
> + *
> + * NOTE: max size 56 bytes, see man rdma_connect().
> + */
> +struct rtrs_msg_conn_req {
> +	/* Is set to 0 by cma.c in case of AF_IB, do not touch that.
> +	 * see https://www.spinics.net/lists/linux-rdma/msg22397.html
> +	 */
> +	u8		__cma_version;
> +	/* On sender side that should be set to 0, or cma_save_ip_info()
> +	 * extract garbage and will fail.
> +	 */
> +	u8		__ip_version;
> +	__le16		magic;
> +	__le16		version;
> +	__le16		cid;
> +	__le16		cid_num;
> +	__le16		recon_cnt;
> +	uuid_t		sess_uuid;
> +	uuid_t		paths_uuid;
> +	u8		reserved[12];
> +};
> +
> +/**
> + * struct rtrs_msg_conn_rsp - Server connection response to the client
> + * @magic:	   RTRS magic
> + * @version:	   RTRS protocol version
> + * @errno:	   If rdma_accept() then 0, if rdma_reject() indicates error
> + * @queue_depth:   max inflight messages (queue-depth) in this session
> + * @max_io_size:   max io size server supports
> + * @max_hdr_size:  max msg header size server supports
> + *
> + * NOTE: size is 56 bytes, max possible is 136 bytes, see man rdma_accept().
> + */
> +struct rtrs_msg_conn_rsp {
> +	__le16		magic;
> +	__le16		version;
> +	__le16		errno;
> +	__le16		queue_depth;
> +	__le32		max_io_size;
> +	__le32		max_hdr_size;
> +	__le32		flags;
> +	u8		reserved[36];
> +};
> +
> +/**
> + * struct rtrs_msg_info_req
> + * @type:		@RTRS_MSG_INFO_REQ
> + * @sessname:		Session name chosen by client
> + */
> +struct rtrs_msg_info_req {
> +	__le16		type;
> +	u8		sessname[NAME_MAX];
> +	u8		reserved[15];
> +};
> +
> +/**
> + * struct rtrs_msg_info_rsp
> + * @type:		@RTRS_MSG_INFO_RSP
> + * @sg_cnt:		Number of @desc entries
> + * @desc:		RDMA buffers where the client can write to server
> + */
> +struct rtrs_msg_info_rsp {
> +	__le16		type;
> +	__le16          sg_cnt;
> +	u8              reserved[4];
> +	struct rtrs_sg_desc desc[];
> +};
> +
> +/**
> + * struct rtrs_msg_rkey_rsp
> + * @type:		@RTRS_MSG_RKEY_RSP
> + * @buf_id:		RDMA buf_id of the new rkey
> + * @rkey:		new remote key for RDMA buffers id from server
> + */
> +struct rtrs_msg_rkey_rsp {
> +	__le16		type;
> +	__le16          buf_id;
> +	__le32		rkey;
> +};
> +
> +/**
> + * struct rtrs_msg_rdma_read - RDMA data transfer request from client
> + * @type:		always @RTRS_MSG_READ
> + * @usr_len:		length of user payload
> + * @sg_cnt:		number of @desc entries
> + * @desc:		RDMA buffers where the server can write the result to
> + */
> +struct rtrs_msg_rdma_read {
> +	__le16			type;
> +	__le16			usr_len;
> +	__le16			flags;
> +	__le16			sg_cnt;
> +	struct rtrs_sg_desc    desc[];
> +};
> +
> +/**
> + * struct_msg_rdma_write - Message transferred to server with RDMA-Write
> + * @type:		always @RTRS_MSG_WRITE
> + * @usr_len:		length of user payload
> + */
> +struct rtrs_msg_rdma_write {
> +	__le16			type;
> +	__le16			usr_len;
> +};
> +
> +/**
> + * struct_msg_rdma_hdr - header for read or write request
> + * @type:		@RTRS_MSG_WRITE | @RTRS_MSG_READ
> + */
> +struct rtrs_msg_rdma_hdr {
> +	__le16			type;
> +};
> +
> +/* rtrs.c */
> +
> +struct rtrs_iu *rtrs_iu_alloc(u32 queue_size, size_t size, gfp_t t,
> +			      struct ib_device *dev, enum dma_data_direction,
> +			      void (*done)(struct ib_cq *cq, struct ib_wc *wc));
> +void rtrs_iu_free(struct rtrs_iu *iu, enum dma_data_direction dir,
> +		  struct ib_device *dev, u32 queue_size);
> +int rtrs_iu_post_recv(struct rtrs_con *con, struct rtrs_iu *iu);
> +int rtrs_iu_post_send(struct rtrs_con *con, struct rtrs_iu *iu, size_t size,
> +		      struct ib_send_wr *head);
> +int rtrs_iu_post_rdma_write_imm(struct rtrs_con *con, struct rtrs_iu *iu,
> +				struct ib_sge *sge, unsigned int num_sge,
> +				u32 rkey, u64 rdma_addr, u32 imm_data,
> +				enum ib_send_flags flags,
> +				struct ib_send_wr *head);
> +
> +int rtrs_post_recv_empty(struct rtrs_con *con, struct ib_cqe *cqe);
> +int rtrs_post_rdma_write_imm_empty(struct rtrs_con *con, struct ib_cqe *cqe,
> +				   u32 imm_data, enum ib_send_flags flags,
> +				   struct ib_send_wr *head);
> +
> +int rtrs_cq_qp_create(struct rtrs_sess *rtrs_sess, struct rtrs_con *con,
> +		      u32 max_send_sge, int cq_vector, u16 cq_size,
> +		      u16 wr_queue_size, enum ib_poll_context poll_ctx);
> +void rtrs_cq_qp_destroy(struct rtrs_con *con);
> +
> +void rtrs_init_hb(struct rtrs_sess *sess, struct ib_cqe *cqe,
> +		  unsigned int interval_ms, unsigned int missed_max,
> +		  rtrs_hb_handler_t *err_handler,
> +		  struct workqueue_struct *wq);
> +void rtrs_start_hb(struct rtrs_sess *sess);
> +void rtrs_stop_hb(struct rtrs_sess *sess);
> +void rtrs_send_hb_ack(struct rtrs_sess *sess);
> +
> +void rtrs_rdma_dev_pd_init(enum ib_pd_flags pd_flags,
> +			   struct rtrs_rdma_dev_pd *pool);
> +void rtrs_rdma_dev_pd_deinit(struct rtrs_rdma_dev_pd *pool);
> +
> +struct rtrs_ib_dev *rtrs_ib_dev_find_or_add(struct ib_device *ib_dev,
> +					    struct rtrs_rdma_dev_pd *pool);
> +int rtrs_ib_dev_put(struct rtrs_ib_dev *dev);
> +
> +static inline u32 rtrs_to_imm(u32 type, u32 payload)
> +{
> +	BUILD_BUG_ON(MAX_IMM_PAYL_BITS + MAX_IMM_TYPE_BITS != 32);
> +	BUILD_BUG_ON(RTRS_LAST_IMM > (1<<MAX_IMM_TYPE_BITS));
> +	return ((type & MAX_IMM_TYPE_MASK) << MAX_IMM_PAYL_BITS) |
> +		(payload & MAX_IMM_PAYL_MASK);
> +}
> +
> +static inline void rtrs_from_imm(u32 imm, u32 *type, u32 *payload)
> +{
> +	*payload = imm & MAX_IMM_PAYL_MASK;
> +	*type = imm >> MAX_IMM_PAYL_BITS;
> +}
> +
> +static inline u32 rtrs_to_io_req_imm(u32 addr)
> +{
> +	return rtrs_to_imm(RTRS_IO_REQ_IMM, addr);
> +}
> +
> +static inline u32 rtrs_to_io_rsp_imm(u32 msg_id, int errno, bool w_inval)
> +{
> +	enum rtrs_imm_type type;
> +	u32 payload;
> +
> +	/* 9 bits for errno, 19 bits for msg_id */
> +	payload = (abs(errno) & 0x1ff) << 19 | (msg_id & 0x7ffff);
> +	type = w_inval ? RTRS_IO_RSP_W_INV_IMM : RTRS_IO_RSP_IMM;
> +
> +	return rtrs_to_imm(type, payload);
> +}
> +
> +static inline void rtrs_from_io_rsp_imm(u32 payload, u32 *msg_id, int *errno)
> +{
> +	/* 9 bits for errno, 19 bits for msg_id */
> +	*msg_id = payload & 0x7ffff;
> +	*errno = -(int)((payload >> 19) & 0x1ff);
> +}
> +
> +#define STAT_STORE_FUNC(type, set_value, reset)				\
> +static ssize_t set_value##_store(struct kobject *kobj,			\
> +			     struct kobj_attribute *attr,		\
> +			     const char *buf, size_t count)		\
> +{									\
> +	int ret = -EINVAL;						\
> +	type *sess = container_of(kobj, type, kobj_stats);		\
> +									\
> +	if (sysfs_streq(buf, "1"))					\
> +		ret = reset(&sess->stats, true);			\
> +	else if (sysfs_streq(buf, "0"))					\
> +		ret = reset(&sess->stats, false);			\
> +	if (ret)							\
> +		return ret;						\
> +									\
> +	return count;							\
> +}
> +
> +#define STAT_SHOW_FUNC(type, get_value, print)				\
> +static ssize_t get_value##_show(struct kobject *kobj,			\
> +			   struct kobj_attribute *attr,			\
> +			   char *page)					\
> +{									\
> +	type *sess = container_of(kobj, type, kobj_stats);		\
> +									\
> +	return print(&sess->stats, page, PAGE_SIZE);			\
> +}
> +
> +#define STAT_ATTR(type, stat, print, reset)				\
> +STAT_STORE_FUNC(type, stat, reset)					\
> +STAT_SHOW_FUNC(type, stat, print)					\
> +static struct kobj_attribute stat##_attr = __ATTR_RW(stat)

It is very strange that you needed to implement _store()/_show() primitives.
Why is that?

> +
> +#endif /* RTRS_PRI_H */
> --
> 2.17.1
>
Jinpu Wang March 3, 2020, 1:52 p.m. UTC | #4 
On Tue, Mar 3, 2020 at 10:45 AM Leon Romanovsky <leon@kernel.org> wrote:
>
> On Fri, Feb 21, 2020 at 11:46:59AM +0100, Jack Wang wrote:
> > From: Jack Wang <jinpu.wang@cloud.ionos.com>
> >
> > These are common private headers with rtrs protocol structures,
> > logging, sysfs and other helper functions, which are used on
> > both client and server sides.
> >
> > Signed-off-by: Danil Kipnis <danil.kipnis@cloud.ionos.com>
> > Signed-off-by: Jack Wang <jinpu.wang@cloud.ionos.com>
> > ---
> >  drivers/infiniband/ulp/rtrs/rtrs-log.h |  28 ++
> >  drivers/infiniband/ulp/rtrs/rtrs-pri.h | 401 +++++++++++++++++++++++++
> >  2 files changed, 429 insertions(+)
> >  create mode 100644 drivers/infiniband/ulp/rtrs/rtrs-log.h
> >  create mode 100644 drivers/infiniband/ulp/rtrs/rtrs-pri.h
> >
> > diff --git a/drivers/infiniband/ulp/rtrs/rtrs-log.h b/drivers/infiniband/ulp/rtrs/rtrs-log.h
> > new file mode 100644
> > index 000000000000..53c785b992f2
> > --- /dev/null
> > +++ b/drivers/infiniband/ulp/rtrs/rtrs-log.h
> > @@ -0,0 +1,28 @@
> > +/* SPDX-License-Identifier: GPL-2.0-or-later */
> > +/*
> > + * RDMA Transport Layer
> > + *
> > + * Copyright (c) 2014 - 2018 ProfitBricks GmbH. All rights reserved.
> > + * Copyright (c) 2018 - 2019 1&1 IONOS Cloud GmbH. All rights reserved.
> > + * Copyright (c) 2019 - 2020 1&1 IONOS SE. All rights reserved.
> > + */
> > +#ifndef RTRS_LOG_H
> > +#define RTRS_LOG_H
> > +
> > +#define rtrs_log(fn, obj, fmt, ...)                          \
> > +     fn("<%s>: " fmt, obj->sessname, ##__VA_ARGS__)
> > +
> > +#define rtrs_err(obj, fmt, ...)      \
> > +     rtrs_log(pr_err, obj, fmt, ##__VA_ARGS__)
> > +#define rtrs_err_rl(obj, fmt, ...)   \
> > +     rtrs_log(pr_err_ratelimited, obj, fmt, ##__VA_ARGS__)
> > +#define rtrs_wrn(obj, fmt, ...)      \
> > +     rtrs_log(pr_warn, obj, fmt, ##__VA_ARGS__)
> > +#define rtrs_wrn_rl(obj, fmt, ...) \
> > +     rtrs_log(pr_warn_ratelimited, obj, fmt, ##__VA_ARGS__)
> > +#define rtrs_info(obj, fmt, ...) \
> > +     rtrs_log(pr_info, obj, fmt, ##__VA_ARGS__)
> > +#define rtrs_info_rl(obj, fmt, ...) \
> > +     rtrs_log(pr_info_ratelimited, obj, fmt, ##__VA_ARGS__)
> > +
> > +#endif /* RTRS_LOG_H */
> > diff --git a/drivers/infiniband/ulp/rtrs/rtrs-pri.h b/drivers/infiniband/ulp/rtrs/rtrs-pri.h
> > new file mode 100644
> > index 000000000000..aecf01a7d8dc
> > --- /dev/null
> > +++ b/drivers/infiniband/ulp/rtrs/rtrs-pri.h
> > @@ -0,0 +1,401 @@
> > +/* SPDX-License-Identifier: GPL-2.0-or-later */
> > +/*
> > + * RDMA Transport Layer
> > + *
> > + * Copyright (c) 2014 - 2018 ProfitBricks GmbH. All rights reserved.
> > + * Copyright (c) 2018 - 2019 1&1 IONOS Cloud GmbH. All rights reserved.
> > + * Copyright (c) 2019 - 2020 1&1 IONOS SE. All rights reserved.
> > + */
> > +
> > +#ifndef RTRS_PRI_H
> > +#define RTRS_PRI_H
> > +
> > +#include <linux/uuid.h>
> > +#include <rdma/rdma_cm.h>
> > +#include <rdma/ib_verbs.h>
> > +#include <rdma/ib.h>
> > +
> > +#include "rtrs.h"
> > +
> > +#define RTRS_PROTO_VER_MAJOR 2
> > +#define RTRS_PROTO_VER_MINOR 0
>
> I think that Jason once said that new submission starts from "1".
> There is no RTRS_PROTO_VER_MAJOR == 1 in the wild.
sorry, v2 protocol is already in our production, we can simple change back to v1


> > +#define STAT_ATTR(type, stat, print, reset)                          \
> > +STAT_STORE_FUNC(type, stat, reset)                                   \
> > +STAT_SHOW_FUNC(type, stat, print)                                    \
> > +static struct kobj_attribute stat##_attr = __ATTR_RW(stat)
>
> It is very strange that you needed to implement _store()/_show() primitives.
> Why is that?
We define the MICRO to save some line of code when implementing the
stats like rdma/reconects/etc, sess rtrs-clt-sysfs.c/srts-srv-sysfs.c

Thanks!
Jason Gunthorpe March 3, 2020, 2:05 p.m. UTC | #5 
On Tue, Mar 03, 2020 at 02:52:19PM +0100, Jinpu Wang wrote:
> On Tue, Mar 3, 2020 at 10:45 AM Leon Romanovsky <leon@kernel.org> wrote:
> >
> > On Fri, Feb 21, 2020 at 11:46:59AM +0100, Jack Wang wrote:
> > > From: Jack Wang <jinpu.wang@cloud.ionos.com>
> > >
> > > These are common private headers with rtrs protocol structures,
> > > logging, sysfs and other helper functions, which are used on
> > > both client and server sides.
> > >
> > > Signed-off-by: Danil Kipnis <danil.kipnis@cloud.ionos.com>
> > > Signed-off-by: Jack Wang <jinpu.wang@cloud.ionos.com>
> > >  drivers/infiniband/ulp/rtrs/rtrs-log.h |  28 ++
> > >  drivers/infiniband/ulp/rtrs/rtrs-pri.h | 401 +++++++++++++++++++++++++
> > >  2 files changed, 429 insertions(+)
> > >  create mode 100644 drivers/infiniband/ulp/rtrs/rtrs-log.h
> > >  create mode 100644 drivers/infiniband/ulp/rtrs/rtrs-pri.h
> > >
> > > diff --git a/drivers/infiniband/ulp/rtrs/rtrs-log.h b/drivers/infiniband/ulp/rtrs/rtrs-log.h
> > > new file mode 100644
> > > index 000000000000..53c785b992f2
> > > +++ b/drivers/infiniband/ulp/rtrs/rtrs-log.h
> > > @@ -0,0 +1,28 @@
> > > +/* SPDX-License-Identifier: GPL-2.0-or-later */
> > > +/*
> > > + * RDMA Transport Layer
> > > + *
> > > + * Copyright (c) 2014 - 2018 ProfitBricks GmbH. All rights reserved.
> > > + * Copyright (c) 2018 - 2019 1&1 IONOS Cloud GmbH. All rights reserved.
> > > + * Copyright (c) 2019 - 2020 1&1 IONOS SE. All rights reserved.
> > > + */
> > > +#ifndef RTRS_LOG_H
> > > +#define RTRS_LOG_H
> > > +
> > > +#define rtrs_log(fn, obj, fmt, ...)                          \
> > > +     fn("<%s>: " fmt, obj->sessname, ##__VA_ARGS__)
> > > +
> > > +#define rtrs_err(obj, fmt, ...)      \
> > > +     rtrs_log(pr_err, obj, fmt, ##__VA_ARGS__)
> > > +#define rtrs_err_rl(obj, fmt, ...)   \
> > > +     rtrs_log(pr_err_ratelimited, obj, fmt, ##__VA_ARGS__)
> > > +#define rtrs_wrn(obj, fmt, ...)      \
> > > +     rtrs_log(pr_warn, obj, fmt, ##__VA_ARGS__)
> > > +#define rtrs_wrn_rl(obj, fmt, ...) \
> > > +     rtrs_log(pr_warn_ratelimited, obj, fmt, ##__VA_ARGS__)
> > > +#define rtrs_info(obj, fmt, ...) \
> > > +     rtrs_log(pr_info, obj, fmt, ##__VA_ARGS__)
> > > +#define rtrs_info_rl(obj, fmt, ...) \
> > > +     rtrs_log(pr_info_ratelimited, obj, fmt, ##__VA_ARGS__)
> > > +
> > > +#endif /* RTRS_LOG_H */
> > > diff --git a/drivers/infiniband/ulp/rtrs/rtrs-pri.h b/drivers/infiniband/ulp/rtrs/rtrs-pri.h
> > > new file mode 100644
> > > index 000000000000..aecf01a7d8dc
> > > +++ b/drivers/infiniband/ulp/rtrs/rtrs-pri.h
> > > @@ -0,0 +1,401 @@
> > > +/* SPDX-License-Identifier: GPL-2.0-or-later */
> > > +/*
> > > + * RDMA Transport Layer
> > > + *
> > > + * Copyright (c) 2014 - 2018 ProfitBricks GmbH. All rights reserved.
> > > + * Copyright (c) 2018 - 2019 1&1 IONOS Cloud GmbH. All rights reserved.
> > > + * Copyright (c) 2019 - 2020 1&1 IONOS SE. All rights reserved.
> > > + */
> > > +
> > > +#ifndef RTRS_PRI_H
> > > +#define RTRS_PRI_H
> > > +
> > > +#include <linux/uuid.h>
> > > +#include <rdma/rdma_cm.h>
> > > +#include <rdma/ib_verbs.h>
> > > +#include <rdma/ib.h>
> > > +
> > > +#include "rtrs.h"
> > > +
> > > +#define RTRS_PROTO_VER_MAJOR 2
> > > +#define RTRS_PROTO_VER_MINOR 0
> >
> > I think that Jason once said that new submission starts from "1".
> > There is no RTRS_PROTO_VER_MAJOR == 1 in the wild.
> sorry, v2 protocol is already in our production, we can simple change back to v1

I think my comment in the past was about the verb ABI number

You should arrange this so you can use it in your production, if you
use something else then we are we upstreaming it?

As a community we have had bad experience with companies upstreaming
something that they ultimately do not use.

Jason
Jinpu Wang March 3, 2020, 4:13 p.m. UTC | #6 
On Tue, Mar 3, 2020 at 3:05 PM Jason Gunthorpe <jgg@ziepe.ca> wrote:
>
> On Tue, Mar 03, 2020 at 02:52:19PM +0100, Jinpu Wang wrote:
> > On Tue, Mar 3, 2020 at 10:45 AM Leon Romanovsky <leon@kernel.org> wrote:
> > >
> > > On Fri, Feb 21, 2020 at 11:46:59AM +0100, Jack Wang wrote:
> > > > From: Jack Wang <jinpu.wang@cloud.ionos.com>
> > > >
> > > > These are common private headers with rtrs protocol structures,
> > > > logging, sysfs and other helper functions, which are used on
> > > > both client and server sides.
> > > >
> > > > Signed-off-by: Danil Kipnis <danil.kipnis@cloud.ionos.com>
> > > > Signed-off-by: Jack Wang <jinpu.wang@cloud.ionos.com>
> > > >  drivers/infiniband/ulp/rtrs/rtrs-log.h |  28 ++
> > > >  drivers/infiniband/ulp/rtrs/rtrs-pri.h | 401 +++++++++++++++++++++++++
> > > >  2 files changed, 429 insertions(+)
> > > >  create mode 100644 drivers/infiniband/ulp/rtrs/rtrs-log.h
> > > >  create mode 100644 drivers/infiniband/ulp/rtrs/rtrs-pri.h
> > > >
> > > > diff --git a/drivers/infiniband/ulp/rtrs/rtrs-log.h b/drivers/infiniband/ulp/rtrs/rtrs-log.h
> > > > new file mode 100644
> > > > index 000000000000..53c785b992f2
> > > > +++ b/drivers/infiniband/ulp/rtrs/rtrs-log.h
> > > > @@ -0,0 +1,28 @@
> > > > +/* SPDX-License-Identifier: GPL-2.0-or-later */
> > > > +/*
> > > > + * RDMA Transport Layer
> > > > + *
> > > > + * Copyright (c) 2014 - 2018 ProfitBricks GmbH. All rights reserved.
> > > > + * Copyright (c) 2018 - 2019 1&1 IONOS Cloud GmbH. All rights reserved.
> > > > + * Copyright (c) 2019 - 2020 1&1 IONOS SE. All rights reserved.
> > > > + */
> > > > +#ifndef RTRS_LOG_H
> > > > +#define RTRS_LOG_H
> > > > +
> > > > +#define rtrs_log(fn, obj, fmt, ...)                          \
> > > > +     fn("<%s>: " fmt, obj->sessname, ##__VA_ARGS__)
> > > > +
> > > > +#define rtrs_err(obj, fmt, ...)      \
> > > > +     rtrs_log(pr_err, obj, fmt, ##__VA_ARGS__)
> > > > +#define rtrs_err_rl(obj, fmt, ...)   \
> > > > +     rtrs_log(pr_err_ratelimited, obj, fmt, ##__VA_ARGS__)
> > > > +#define rtrs_wrn(obj, fmt, ...)      \
> > > > +     rtrs_log(pr_warn, obj, fmt, ##__VA_ARGS__)
> > > > +#define rtrs_wrn_rl(obj, fmt, ...) \
> > > > +     rtrs_log(pr_warn_ratelimited, obj, fmt, ##__VA_ARGS__)
> > > > +#define rtrs_info(obj, fmt, ...) \
> > > > +     rtrs_log(pr_info, obj, fmt, ##__VA_ARGS__)
> > > > +#define rtrs_info_rl(obj, fmt, ...) \
> > > > +     rtrs_log(pr_info_ratelimited, obj, fmt, ##__VA_ARGS__)
> > > > +
> > > > +#endif /* RTRS_LOG_H */
> > > > diff --git a/drivers/infiniband/ulp/rtrs/rtrs-pri.h b/drivers/infiniband/ulp/rtrs/rtrs-pri.h
> > > > new file mode 100644
> > > > index 000000000000..aecf01a7d8dc
> > > > +++ b/drivers/infiniband/ulp/rtrs/rtrs-pri.h
> > > > @@ -0,0 +1,401 @@
> > > > +/* SPDX-License-Identifier: GPL-2.0-or-later */
> > > > +/*
> > > > + * RDMA Transport Layer
> > > > + *
> > > > + * Copyright (c) 2014 - 2018 ProfitBricks GmbH. All rights reserved.
> > > > + * Copyright (c) 2018 - 2019 1&1 IONOS Cloud GmbH. All rights reserved.
> > > > + * Copyright (c) 2019 - 2020 1&1 IONOS SE. All rights reserved.
> > > > + */
> > > > +
> > > > +#ifndef RTRS_PRI_H
> > > > +#define RTRS_PRI_H
> > > > +
> > > > +#include <linux/uuid.h>
> > > > +#include <rdma/rdma_cm.h>
> > > > +#include <rdma/ib_verbs.h>
> > > > +#include <rdma/ib.h>
> > > > +
> > > > +#include "rtrs.h"
> > > > +
> > > > +#define RTRS_PROTO_VER_MAJOR 2
> > > > +#define RTRS_PROTO_VER_MINOR 0
> > >
> > > I think that Jason once said that new submission starts from "1".
> > > There is no RTRS_PROTO_VER_MAJOR == 1 in the wild.
> > sorry, v2 protocol is already in our production, we can simple change back to v1
>
Hi Jason,

> You should arrange this so you can use it in your production, if you
> use something else then we are we upstreaming it?
We do have the plan to use upstream once we are in upstream, and
that's the reason why we spend the effort to push it upstream,
and we sure would like to see it been used outside of our company, so
more users could benefit.
>
> As a community we have had bad experience with companies upstreaming
> something that they ultimately do not use.

That's the part we are doing now, we want to discuss with the
community to get to a win-win situation.
For myself I joined the community for more than 10 years now, started
from upstream a SAS adapter driver called pm8001, I'm still
maintaining it,
reviewing patches and so on. For RNBD/RTRS, I sure will do the same.

Thanks!
diff mbox series

Patch

diff --git a/drivers/infiniband/ulp/rtrs/rtrs-log.h b/drivers/infiniband/ulp/rtrs/rtrs-log.h
new file mode 100644
index 000000000000..53c785b992f2
--- /dev/null
+++ b/drivers/infiniband/ulp/rtrs/rtrs-log.h
@@ -0,0 +1,28 @@ 
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ * RDMA Transport Layer
+ *
+ * Copyright (c) 2014 - 2018 ProfitBricks GmbH. All rights reserved.
+ * Copyright (c) 2018 - 2019 1&1 IONOS Cloud GmbH. All rights reserved.
+ * Copyright (c) 2019 - 2020 1&1 IONOS SE. All rights reserved.
+ */
+#ifndef RTRS_LOG_H
+#define RTRS_LOG_H
+
+#define rtrs_log(fn, obj, fmt, ...)				\
+	fn("<%s>: " fmt, obj->sessname, ##__VA_ARGS__)
+
+#define rtrs_err(obj, fmt, ...)	\
+	rtrs_log(pr_err, obj, fmt, ##__VA_ARGS__)
+#define rtrs_err_rl(obj, fmt, ...)	\
+	rtrs_log(pr_err_ratelimited, obj, fmt, ##__VA_ARGS__)
+#define rtrs_wrn(obj, fmt, ...)	\
+	rtrs_log(pr_warn, obj, fmt, ##__VA_ARGS__)
+#define rtrs_wrn_rl(obj, fmt, ...) \
+	rtrs_log(pr_warn_ratelimited, obj, fmt, ##__VA_ARGS__)
+#define rtrs_info(obj, fmt, ...) \
+	rtrs_log(pr_info, obj, fmt, ##__VA_ARGS__)
+#define rtrs_info_rl(obj, fmt, ...) \
+	rtrs_log(pr_info_ratelimited, obj, fmt, ##__VA_ARGS__)
+
+#endif /* RTRS_LOG_H */
diff --git a/drivers/infiniband/ulp/rtrs/rtrs-pri.h b/drivers/infiniband/ulp/rtrs/rtrs-pri.h
new file mode 100644
index 000000000000..aecf01a7d8dc
--- /dev/null
+++ b/drivers/infiniband/ulp/rtrs/rtrs-pri.h
@@ -0,0 +1,401 @@ 
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ * RDMA Transport Layer
+ *
+ * Copyright (c) 2014 - 2018 ProfitBricks GmbH. All rights reserved.
+ * Copyright (c) 2018 - 2019 1&1 IONOS Cloud GmbH. All rights reserved.
+ * Copyright (c) 2019 - 2020 1&1 IONOS SE. All rights reserved.
+ */
+
+#ifndef RTRS_PRI_H
+#define RTRS_PRI_H
+
+#include <linux/uuid.h>
+#include <rdma/rdma_cm.h>
+#include <rdma/ib_verbs.h>
+#include <rdma/ib.h>
+
+#include "rtrs.h"
+
+#define RTRS_PROTO_VER_MAJOR 2
+#define RTRS_PROTO_VER_MINOR 0
+
+#define RTRS_PROTO_VER_STRING __stringify(RTRS_PROTO_VER_MAJOR) "." \
+			       __stringify(RTRS_PROTO_VER_MINOR)
+
+enum rtrs_imm_const {
+	MAX_IMM_TYPE_BITS = 4,
+	MAX_IMM_TYPE_MASK = ((1 << MAX_IMM_TYPE_BITS) - 1),
+	MAX_IMM_PAYL_BITS = 28,
+	MAX_IMM_PAYL_MASK = ((1 << MAX_IMM_PAYL_BITS) - 1),
+};
+
+enum rtrs_imm_type {
+	RTRS_IO_REQ_IMM       = 0, /* client to server */
+	RTRS_IO_RSP_IMM       = 1, /* server to client */
+	RTRS_IO_RSP_W_INV_IMM = 2, /* server to client */
+
+	RTRS_HB_MSG_IMM = 8,
+	RTRS_HB_ACK_IMM = 9,
+
+	RTRS_LAST_IMM,
+};
+
+enum {
+	SERVICE_CON_QUEUE_DEPTH = 512,
+
+	MAX_PATHS_NUM = 128,
+
+	/*
+	 * With the size of struct rtrs_permit allocated on the client, 4K
+	 * is the maximum number of rtrs_permits we can allocate. This number is
+	 * also used on the client to allocate the IU for the user connection
+	 * to receive the RDMA addresses from the server.
+	 */
+	MAX_SESS_QUEUE_DEPTH = 4096,
+
+	RTRS_HB_INTERVAL_MS = 5000,
+	RTRS_HB_MISSED_MAX = 5,
+
+	RTRS_MAGIC = 0x1BBD,
+	RTRS_PROTO_VER = (RTRS_PROTO_VER_MAJOR << 8) | RTRS_PROTO_VER_MINOR,
+};
+
+struct rtrs_ib_dev;
+
+struct rtrs_rdma_dev_pd_ops {
+	struct rtrs_ib_dev *(*alloc)(void);
+	void (*free)(struct rtrs_ib_dev *dev);
+	int (*init)(struct rtrs_ib_dev *dev);
+	void (*deinit)(struct rtrs_ib_dev *dev);
+};
+
+struct rtrs_rdma_dev_pd {
+	struct mutex		mutex;
+	struct list_head	list;
+	enum ib_pd_flags	pd_flags;
+	const struct rtrs_rdma_dev_pd_ops *ops;
+};
+
+struct rtrs_ib_dev {
+	struct ib_device	 *ib_dev;
+	struct ib_pd		 *ib_pd;
+	struct kref		 ref;
+	struct list_head	 entry;
+	struct rtrs_rdma_dev_pd *pool;
+};
+
+struct rtrs_con {
+	struct rtrs_sess	*sess;
+	struct ib_qp		*qp;
+	struct ib_cq		*cq;
+	struct rdma_cm_id	*cm_id;
+	unsigned int		cid;
+};
+
+typedef void (rtrs_hb_handler_t)(struct rtrs_con *con);
+
+struct rtrs_sess {
+	struct list_head	entry;
+	struct sockaddr_storage dst_addr;
+	struct sockaddr_storage src_addr;
+	char			sessname[NAME_MAX];
+	uuid_t			uuid;
+	struct rtrs_con	**con;
+	unsigned int		con_num;
+	unsigned int		recon_cnt;
+	struct rtrs_ib_dev	*dev;
+	int			dev_ref;
+	struct ib_cqe		*hb_cqe;
+	rtrs_hb_handler_t	*hb_err_handler;
+	struct workqueue_struct *hb_wq;
+	struct delayed_work	hb_dwork;
+	unsigned int		hb_interval_ms;
+	unsigned int		hb_missed_cnt;
+	unsigned int		hb_missed_max;
+};
+
+/* rtrs information unit */
+struct rtrs_iu {
+	struct list_head        list;
+	struct ib_cqe           cqe;
+	dma_addr_t              dma_addr;
+	void                    *buf;
+	size_t                  size;
+	enum dma_data_direction direction;
+};
+
+/**
+ * enum rtrs_msg_types - RTRS message types, see also rtrs/README
+ * @RTRS_MSG_INFO_REQ:		Client additional info request to the server
+ * @RTRS_MSG_INFO_RSP:		Server additional info response to the client
+ * @RTRS_MSG_WRITE:		Client writes data per RDMA to server
+ * @RTRS_MSG_READ:		Client requests data transfer from server
+ * @RTRS_MSG_RKEY_RSP:		Server refreshed rkey for rbuf
+ */
+enum rtrs_msg_types {
+	RTRS_MSG_INFO_REQ,
+	RTRS_MSG_INFO_RSP,
+	RTRS_MSG_WRITE,
+	RTRS_MSG_READ,
+	RTRS_MSG_RKEY_RSP,
+};
+
+/**
+ * enum rtrs_msg_flags - RTRS message flags.
+ * @RTRS_NEED_INVAL:	Send invalidation in response.
+ * @RTRS_MSG_NEW_RKEY_F: Send refreshed rkey in response.
+ */
+enum rtrs_msg_flags {
+	RTRS_MSG_NEED_INVAL_F = 1 << 0,
+	RTRS_MSG_NEW_RKEY_F = 1 << 1,
+};
+
+/**
+ * struct rtrs_sg_desc - RDMA-Buffer entry description
+ * @addr:	Address of RDMA destination buffer
+ * @key:	Authorization rkey to write to the buffer
+ * @len:	Size of the buffer
+ */
+struct rtrs_sg_desc {
+	__le64			addr;
+	__le32			key;
+	__le32			len;
+};
+
+/**
+ * struct rtrs_msg_conn_req - Client connection request to the server
+ * @magic:	   RTRS magic
+ * @version:	   RTRS protocol version
+ * @cid:	   Current connection id
+ * @cid_num:	   Number of connections per session
+ * @recon_cnt:	   Reconnections counter
+ * @sess_uuid:	   UUID of a session (path)
+ * @paths_uuid:	   UUID of a group of sessions (paths)
+ *
+ * NOTE: max size 56 bytes, see man rdma_connect().
+ */
+struct rtrs_msg_conn_req {
+	/* Is set to 0 by cma.c in case of AF_IB, do not touch that.
+	 * see https://www.spinics.net/lists/linux-rdma/msg22397.html
+	 */
+	u8		__cma_version;
+	/* On sender side that should be set to 0, or cma_save_ip_info()
+	 * extract garbage and will fail.
+	 */
+	u8		__ip_version;
+	__le16		magic;
+	__le16		version;
+	__le16		cid;
+	__le16		cid_num;
+	__le16		recon_cnt;
+	uuid_t		sess_uuid;
+	uuid_t		paths_uuid;
+	u8		reserved[12];
+};
+
+/**
+ * struct rtrs_msg_conn_rsp - Server connection response to the client
+ * @magic:	   RTRS magic
+ * @version:	   RTRS protocol version
+ * @errno:	   If rdma_accept() then 0, if rdma_reject() indicates error
+ * @queue_depth:   max inflight messages (queue-depth) in this session
+ * @max_io_size:   max io size server supports
+ * @max_hdr_size:  max msg header size server supports
+ *
+ * NOTE: size is 56 bytes, max possible is 136 bytes, see man rdma_accept().
+ */
+struct rtrs_msg_conn_rsp {
+	__le16		magic;
+	__le16		version;
+	__le16		errno;
+	__le16		queue_depth;
+	__le32		max_io_size;
+	__le32		max_hdr_size;
+	__le32		flags;
+	u8		reserved[36];
+};
+
+/**
+ * struct rtrs_msg_info_req
+ * @type:		@RTRS_MSG_INFO_REQ
+ * @sessname:		Session name chosen by client
+ */
+struct rtrs_msg_info_req {
+	__le16		type;
+	u8		sessname[NAME_MAX];
+	u8		reserved[15];
+};
+
+/**
+ * struct rtrs_msg_info_rsp
+ * @type:		@RTRS_MSG_INFO_RSP
+ * @sg_cnt:		Number of @desc entries
+ * @desc:		RDMA buffers where the client can write to server
+ */
+struct rtrs_msg_info_rsp {
+	__le16		type;
+	__le16          sg_cnt;
+	u8              reserved[4];
+	struct rtrs_sg_desc desc[];
+};
+
+/**
+ * struct rtrs_msg_rkey_rsp
+ * @type:		@RTRS_MSG_RKEY_RSP
+ * @buf_id:		RDMA buf_id of the new rkey
+ * @rkey:		new remote key for RDMA buffers id from server
+ */
+struct rtrs_msg_rkey_rsp {
+	__le16		type;
+	__le16          buf_id;
+	__le32		rkey;
+};
+
+/**
+ * struct rtrs_msg_rdma_read - RDMA data transfer request from client
+ * @type:		always @RTRS_MSG_READ
+ * @usr_len:		length of user payload
+ * @sg_cnt:		number of @desc entries
+ * @desc:		RDMA buffers where the server can write the result to
+ */
+struct rtrs_msg_rdma_read {
+	__le16			type;
+	__le16			usr_len;
+	__le16			flags;
+	__le16			sg_cnt;
+	struct rtrs_sg_desc    desc[];
+};
+
+/**
+ * struct_msg_rdma_write - Message transferred to server with RDMA-Write
+ * @type:		always @RTRS_MSG_WRITE
+ * @usr_len:		length of user payload
+ */
+struct rtrs_msg_rdma_write {
+	__le16			type;
+	__le16			usr_len;
+};
+
+/**
+ * struct_msg_rdma_hdr - header for read or write request
+ * @type:		@RTRS_MSG_WRITE | @RTRS_MSG_READ
+ */
+struct rtrs_msg_rdma_hdr {
+	__le16			type;
+};
+
+/* rtrs.c */
+
+struct rtrs_iu *rtrs_iu_alloc(u32 queue_size, size_t size, gfp_t t,
+			      struct ib_device *dev, enum dma_data_direction,
+			      void (*done)(struct ib_cq *cq, struct ib_wc *wc));
+void rtrs_iu_free(struct rtrs_iu *iu, enum dma_data_direction dir,
+		  struct ib_device *dev, u32 queue_size);
+int rtrs_iu_post_recv(struct rtrs_con *con, struct rtrs_iu *iu);
+int rtrs_iu_post_send(struct rtrs_con *con, struct rtrs_iu *iu, size_t size,
+		      struct ib_send_wr *head);
+int rtrs_iu_post_rdma_write_imm(struct rtrs_con *con, struct rtrs_iu *iu,
+				struct ib_sge *sge, unsigned int num_sge,
+				u32 rkey, u64 rdma_addr, u32 imm_data,
+				enum ib_send_flags flags,
+				struct ib_send_wr *head);
+
+int rtrs_post_recv_empty(struct rtrs_con *con, struct ib_cqe *cqe);
+int rtrs_post_rdma_write_imm_empty(struct rtrs_con *con, struct ib_cqe *cqe,
+				   u32 imm_data, enum ib_send_flags flags,
+				   struct ib_send_wr *head);
+
+int rtrs_cq_qp_create(struct rtrs_sess *rtrs_sess, struct rtrs_con *con,
+		      u32 max_send_sge, int cq_vector, u16 cq_size,
+		      u16 wr_queue_size, enum ib_poll_context poll_ctx);
+void rtrs_cq_qp_destroy(struct rtrs_con *con);
+
+void rtrs_init_hb(struct rtrs_sess *sess, struct ib_cqe *cqe,
+		  unsigned int interval_ms, unsigned int missed_max,
+		  rtrs_hb_handler_t *err_handler,
+		  struct workqueue_struct *wq);
+void rtrs_start_hb(struct rtrs_sess *sess);
+void rtrs_stop_hb(struct rtrs_sess *sess);
+void rtrs_send_hb_ack(struct rtrs_sess *sess);
+
+void rtrs_rdma_dev_pd_init(enum ib_pd_flags pd_flags,
+			   struct rtrs_rdma_dev_pd *pool);
+void rtrs_rdma_dev_pd_deinit(struct rtrs_rdma_dev_pd *pool);
+
+struct rtrs_ib_dev *rtrs_ib_dev_find_or_add(struct ib_device *ib_dev,
+					    struct rtrs_rdma_dev_pd *pool);
+int rtrs_ib_dev_put(struct rtrs_ib_dev *dev);
+
+static inline u32 rtrs_to_imm(u32 type, u32 payload)
+{
+	BUILD_BUG_ON(MAX_IMM_PAYL_BITS + MAX_IMM_TYPE_BITS != 32);
+	BUILD_BUG_ON(RTRS_LAST_IMM > (1<<MAX_IMM_TYPE_BITS));
+	return ((type & MAX_IMM_TYPE_MASK) << MAX_IMM_PAYL_BITS) |
+		(payload & MAX_IMM_PAYL_MASK);
+}
+
+static inline void rtrs_from_imm(u32 imm, u32 *type, u32 *payload)
+{
+	*payload = imm & MAX_IMM_PAYL_MASK;
+	*type = imm >> MAX_IMM_PAYL_BITS;
+}
+
+static inline u32 rtrs_to_io_req_imm(u32 addr)
+{
+	return rtrs_to_imm(RTRS_IO_REQ_IMM, addr);
+}
+
+static inline u32 rtrs_to_io_rsp_imm(u32 msg_id, int errno, bool w_inval)
+{
+	enum rtrs_imm_type type;
+	u32 payload;
+
+	/* 9 bits for errno, 19 bits for msg_id */
+	payload = (abs(errno) & 0x1ff) << 19 | (msg_id & 0x7ffff);
+	type = w_inval ? RTRS_IO_RSP_W_INV_IMM : RTRS_IO_RSP_IMM;
+
+	return rtrs_to_imm(type, payload);
+}
+
+static inline void rtrs_from_io_rsp_imm(u32 payload, u32 *msg_id, int *errno)
+{
+	/* 9 bits for errno, 19 bits for msg_id */
+	*msg_id = payload & 0x7ffff;
+	*errno = -(int)((payload >> 19) & 0x1ff);
+}
+
+#define STAT_STORE_FUNC(type, set_value, reset)				\
+static ssize_t set_value##_store(struct kobject *kobj,			\
+			     struct kobj_attribute *attr,		\
+			     const char *buf, size_t count)		\
+{									\
+	int ret = -EINVAL;						\
+	type *sess = container_of(kobj, type, kobj_stats);		\
+									\
+	if (sysfs_streq(buf, "1"))					\
+		ret = reset(&sess->stats, true);			\
+	else if (sysfs_streq(buf, "0"))					\
+		ret = reset(&sess->stats, false);			\
+	if (ret)							\
+		return ret;						\
+									\
+	return count;							\
+}
+
+#define STAT_SHOW_FUNC(type, get_value, print)				\
+static ssize_t get_value##_show(struct kobject *kobj,			\
+			   struct kobj_attribute *attr,			\
+			   char *page)					\
+{									\
+	type *sess = container_of(kobj, type, kobj_stats);		\
+									\
+	return print(&sess->stats, page, PAGE_SIZE);			\
+}
+
+#define STAT_ATTR(type, stat, print, reset)				\
+STAT_STORE_FUNC(type, stat, reset)					\
+STAT_SHOW_FUNC(type, stat, print)					\
+static struct kobj_attribute stat##_attr = __ATTR_RW(stat)
+
+#endif /* RTRS_PRI_H */