1/* SPDX-License-Identifier: GPL-2.0-or-later */
  2/*
  3 * RDMA Network Block Driver
  4 *
  5 * Copyright (c) 2014 - 2018 ProfitBricks GmbH. All rights reserved.
  6 * Copyright (c) 2018 - 2019 1&1 IONOS Cloud GmbH. All rights reserved.
  7 * Copyright (c) 2019 - 2020 1&1 IONOS SE. All rights reserved.
  8 */
  9
 10#ifndef RNBD_CLT_H
 11#define RNBD_CLT_H
 12
 13#include <linux/wait.h>
 14#include <linux/in.h>
 15#include <linux/inet.h>
 16#include <linux/blk-mq.h>
 17#include <linux/refcount.h>
 18
 19#include <rtrs.h>
 20#include "rnbd-proto.h"
 21#include "rnbd-log.h"
 22
 23/*  time in seconds between reconnect tries, default to 30 s */
 24#define RECONNECT_DELAY 30
 25/*
 26 * Number of times to reconnect on error before giving up, 0 for * disabled,
 27 * -1 for forever
 28 */
 29#define MAX_RECONNECTS -1
 30
 31enum rnbd_clt_dev_state {
 32	DEV_STATE_INIT,
 33	DEV_STATE_MAPPED,
 34	DEV_STATE_MAPPED_DISCONNECTED,
 35	DEV_STATE_UNMAPPED,
 36};
 37
 38struct rnbd_iu_comp {
 39	wait_queue_head_t wait;
 40	int errno;
 41};
 42
 43#ifdef CONFIG_ARCH_NO_SG_CHAIN
 44#define RNBD_INLINE_SG_CNT 0
 45#else
 46#define RNBD_INLINE_SG_CNT 2
 47#endif
 48#define RNBD_RDMA_SGL_SIZE (sizeof(struct scatterlist) * RNBD_INLINE_SG_CNT)
 49
 50struct rnbd_iu {
 51	union {
 52		struct request *rq; /* for block io */
 53		void *buf; /* for user messages */
 54	};
 55	struct rtrs_permit	*permit;
 56	union {
 57		/* use to send msg associated with a dev */
 58		struct rnbd_clt_dev *dev;
 59		/* use to send msg associated with a sess */
 60		struct rnbd_clt_session *sess;
 61	};
 62	struct sg_table		sgt;
 63	struct work_struct	work;
 64	int			errno;
 65	struct rnbd_iu_comp	comp;
 66	atomic_t		refcount;
 67	struct scatterlist	first_sgl[]; /* must be the last one */
 68};
 69
 70struct rnbd_cpu_qlist {
 71	struct list_head	requeue_list;
 72	spinlock_t		requeue_lock;
 73	unsigned int		cpu;
 74};
 75
 76struct rnbd_clt_session {
 77	struct list_head        list;
 78	struct rtrs_clt_sess        *rtrs;
 79	wait_queue_head_t       rtrs_waitq;
 80	bool                    rtrs_ready;
 81	struct rnbd_cpu_qlist	__percpu
 82				*cpu_queues;
 83	DECLARE_BITMAP(cpu_queues_bm, NR_CPUS);
 84	int	__percpu	*cpu_rr; /* per-cpu var for CPU round-robin */
 85	atomic_t		busy;
 86	size_t			queue_depth;
 87	u32			max_io_size;
 88	u32			max_segments;
 89	struct blk_mq_tag_set	tag_set;
 90	u32			nr_poll_queues;
 91	struct mutex		lock; /* protects state and devs_list */
 92	struct list_head        devs_list; /* list of struct rnbd_clt_dev */
 93	refcount_t		refcount;
 94	char			sessname[NAME_MAX];
 95	u8			ver; /* protocol version */
 96};
 97
 98/**
 99 * Submission queues.
100 */
101struct rnbd_queue {
102	struct list_head	requeue_list;
103	unsigned long		in_list;
104	struct rnbd_clt_dev	*dev;
105	struct blk_mq_hw_ctx	*hctx;
106};
107
108struct rnbd_clt_dev {
109	struct kobject		kobj;
110	struct rnbd_clt_session	*sess;
111	struct request_queue	*queue;
112	struct rnbd_queue	*hw_queues;
113	u32			device_id;
114	/* local Idr index - used to track minor number allocations. */
115	u32			clt_device_id;
116	struct mutex		lock;
117	enum rnbd_clt_dev_state	dev_state;
118	refcount_t		refcount;
119	char			*pathname;
120	enum rnbd_access_mode	access_mode;
121	u32			nr_poll_queues;
122	u64			size;		/* device size in bytes */
123	struct list_head        list;
124	struct gendisk		*gd;
125	char			*blk_symlink_name;
126	struct work_struct	unmap_on_rmmod_work;
127};
128
129/* rnbd-clt.c */
130
131struct rnbd_clt_dev *rnbd_clt_map_device(const char *sessname,
132					   struct rtrs_addr *paths,
133					   size_t path_cnt, u16 port_nr,
134					   const char *pathname,
135					   enum rnbd_access_mode access_mode,
136					   u32 nr_poll_queues);
137int rnbd_clt_unmap_device(struct rnbd_clt_dev *dev, bool force,
138			   const struct attribute *sysfs_self);
139
140int rnbd_clt_remap_device(struct rnbd_clt_dev *dev);
141int rnbd_clt_resize_disk(struct rnbd_clt_dev *dev, sector_t newsize);
142
143/* rnbd-clt-sysfs.c */
144
145int rnbd_clt_create_sysfs_files(void);
146
147void rnbd_clt_destroy_sysfs_files(void);
148
149void rnbd_clt_remove_dev_symlink(struct rnbd_clt_dev *dev);
150
151#endif /* RNBD_CLT_H */