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+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ * RDMA Network Block Driver
+ *
+ * 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 RNBD_CLT_H
+#define RNBD_CLT_H
+
+#include <linux/wait.h>
+#include <linux/in.h>
+#include <linux/inet.h>
+#include <linux/blk-mq.h>
+#include <linux/refcount.h>
+
+#include "rtrs.h"
+#include "rnbd-proto.h"
+#include "rnbd-log.h"
+
+/* Max. number of segments per IO request, Mellanox Connect X ~ Connect X5,
+ * choose minimial 30 for all, minus 1 for internal protocol, so 29.
+ */
+#define BMAX_SEGMENTS 29
+/* time in seconds between reconnect tries, default to 30 s */
+#define RECONNECT_DELAY 30
+/*
+ * Number of times to reconnect on error before giving up, 0 for * disabled,
+ * -1 for forever
+ */
+#define MAX_RECONNECTS -1
+
+enum rnbd_clt_dev_state {
+ DEV_STATE_INIT,
+ DEV_STATE_MAPPED,
+ DEV_STATE_MAPPED_DISCONNECTED,
+ DEV_STATE_UNMAPPED,
+};
+
+struct rnbd_iu_comp {
+ wait_queue_head_t wait;
+ int errno;
+};
+
+struct rnbd_iu {
+ union {
+ struct request *rq; /* for block io */
+ void *buf; /* for user messages */
+ };
+ struct rtrs_permit *permit;
+ union {
+ /* use to send msg associated with a dev */
+ struct rnbd_clt_dev *dev;
+ /* use to send msg associated with a sess */
+ struct rnbd_clt_session *sess;
+ };
+ struct scatterlist sglist[BMAX_SEGMENTS];
+ struct work_struct work;
+ int errno;
+ struct rnbd_iu_comp comp;
+ atomic_t refcount;
+};
+
+struct rnbd_cpu_qlist {
+ struct list_head requeue_list;
+ spinlock_t requeue_lock;
+ unsigned int cpu;
+};
+
+struct rnbd_clt_session {
+ struct list_head list;
+ struct rtrs_clt *rtrs;
+ wait_queue_head_t rtrs_waitq;
+ bool rtrs_ready;
+ struct rnbd_cpu_qlist __percpu
+ *cpu_queues;
+ DECLARE_BITMAP(cpu_queues_bm, NR_CPUS);
+ int __percpu *cpu_rr; /* per-cpu var for CPU round-robin */
+ atomic_t busy;
+ int queue_depth;
+ u32 max_io_size;
+ struct blk_mq_tag_set tag_set;
+ struct mutex lock; /* protects state and devs_list */
+ struct list_head devs_list; /* list of struct rnbd_clt_dev */
+ refcount_t refcount;
+ char sessname[NAME_MAX];
+ u8 ver; /* protocol version */
+};
+
+/**
+ * Submission queues.
+ */
+struct rnbd_queue {
+ struct list_head requeue_list;
+ unsigned long in_list;
+ struct rnbd_clt_dev *dev;
+ struct blk_mq_hw_ctx *hctx;
+};
+
+struct rnbd_clt_dev {
+ struct rnbd_clt_session *sess;
+ struct request_queue *queue;
+ struct rnbd_queue *hw_queues;
+ u32 device_id;
+ /* local Idr index - used to track minor number allocations. */
+ u32 clt_device_id;
+ struct mutex lock;
+ enum rnbd_clt_dev_state dev_state;
+ char pathname[NAME_MAX];
+ enum rnbd_access_mode access_mode;
+ bool read_only;
+ bool rotational;
+ u32 max_hw_sectors;
+ u32 max_write_same_sectors;
+ u32 max_discard_sectors;
+ u32 discard_granularity;
+ u32 discard_alignment;
+ u16 secure_discard;
+ u16 physical_block_size;
+ u16 logical_block_size;
+ u16 max_segments;
+ size_t nsectors;
+ u64 size; /* device size in bytes */
+ struct list_head list;
+ struct gendisk *gd;
+ struct kobject kobj;
+ char blk_symlink_name[NAME_MAX];
+ refcount_t refcount;
+ struct work_struct unmap_on_rmmod_work;
+};
+
+/* rnbd-clt.c */
+
+struct rnbd_clt_dev *rnbd_clt_map_device(const char *sessname,
+ struct rtrs_addr *paths,
+ size_t path_cnt, u16 port_nr,
+ const char *pathname,
+ enum rnbd_access_mode access_mode);
+int rnbd_clt_unmap_device(struct rnbd_clt_dev *dev, bool force,
+ const struct attribute *sysfs_self);
+
+int rnbd_clt_remap_device(struct rnbd_clt_dev *dev);
+int rnbd_clt_resize_disk(struct rnbd_clt_dev *dev, size_t newsize);
+
+/* rnbd-clt-sysfs.c */
+
+int rnbd_clt_create_sysfs_files(void);
+
+void rnbd_clt_destroy_sysfs_files(void);
+void rnbd_clt_destroy_default_group(void);
+
+void rnbd_clt_remove_dev_symlink(struct rnbd_clt_dev *dev);
+
+#endif /* RNBD_CLT_H */