xref: /openbmc/linux/drivers/block/rnbd/rnbd-clt.h (revision d87c25e8)
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 
31 enum rnbd_clt_dev_state {
32 	DEV_STATE_INIT,
33 	DEV_STATE_MAPPED,
34 	DEV_STATE_MAPPED_DISCONNECTED,
35 	DEV_STATE_UNMAPPED,
36 };
37 
38 struct 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 
50 struct 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 
70 struct rnbd_cpu_qlist {
71 	struct list_head	requeue_list;
72 	spinlock_t		requeue_lock;
73 	unsigned int		cpu;
74 };
75 
76 struct 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  */
101 struct 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 
108 struct rnbd_clt_dev {
109 	struct rnbd_clt_session	*sess;
110 	struct request_queue	*queue;
111 	struct rnbd_queue	*hw_queues;
112 	u32			device_id;
113 	/* local Idr index - used to track minor number allocations. */
114 	u32			clt_device_id;
115 	struct mutex		lock;
116 	enum rnbd_clt_dev_state	dev_state;
117 	char			*pathname;
118 	enum rnbd_access_mode	access_mode;
119 	u32			nr_poll_queues;
120 	bool			read_only;
121 	bool			rotational;
122 	bool			wc;
123 	bool			fua;
124 	u32			max_hw_sectors;
125 	u32			max_write_same_sectors;
126 	u32			max_discard_sectors;
127 	u32			discard_granularity;
128 	u32			discard_alignment;
129 	u16			secure_discard;
130 	u16			physical_block_size;
131 	u16			logical_block_size;
132 	u16			max_segments;
133 	size_t			nsectors;
134 	u64			size;		/* device size in bytes */
135 	struct list_head        list;
136 	struct gendisk		*gd;
137 	struct kobject		kobj;
138 	char			*blk_symlink_name;
139 	refcount_t		refcount;
140 	struct work_struct	unmap_on_rmmod_work;
141 };
142 
143 /* rnbd-clt.c */
144 
145 struct rnbd_clt_dev *rnbd_clt_map_device(const char *sessname,
146 					   struct rtrs_addr *paths,
147 					   size_t path_cnt, u16 port_nr,
148 					   const char *pathname,
149 					   enum rnbd_access_mode access_mode,
150 					   u32 nr_poll_queues);
151 int rnbd_clt_unmap_device(struct rnbd_clt_dev *dev, bool force,
152 			   const struct attribute *sysfs_self);
153 
154 int rnbd_clt_remap_device(struct rnbd_clt_dev *dev);
155 int rnbd_clt_resize_disk(struct rnbd_clt_dev *dev, size_t newsize);
156 
157 /* rnbd-clt-sysfs.c */
158 
159 int rnbd_clt_create_sysfs_files(void);
160 
161 void rnbd_clt_destroy_sysfs_files(void);
162 
163 void rnbd_clt_remove_dev_symlink(struct rnbd_clt_dev *dev);
164 
165 #endif /* RNBD_CLT_H */
166