RDMA/rtrs: private headers with rtrs protocol structs and helpers

/* 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 */

/* 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, /* HB: HeartBeat */

	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;

};

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;

	void			(*hb_err_handler)(struct rtrs_con *con);

	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,

		  void (*err_handler)(struct rtrs_con *con),

		  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 *stats = container_of(kobj, type, kobj_stats);		\

									\

	if (sysfs_streq(buf, "1"))					\

		ret = reset(stats, true);			\

	else if (sysfs_streq(buf, "0"))					\

		ret = reset(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 *stats = container_of(kobj, type, kobj_stats);		\

									\

	return print(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 */