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 */
152

source code of linux/drivers/block/rnbd/rnbd-clt.h