drivers/block/rnbd/rnbd-clt.h

   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 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
 131 struct 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);
 137 int rnbd_clt_unmap_device(struct rnbd_clt_dev *dev, bool force,
 138                            const struct attribute *sysfs_self);
 139
 140 int rnbd_clt_remap_device(struct rnbd_clt_dev *dev);
 141 int rnbd_clt_resize_disk(struct rnbd_clt_dev *dev, sector_t newsize);
 142
 143 /* rnbd-clt-sysfs.c */
 144
 145 int rnbd_clt_create_sysfs_files(void);
 146
 147 void rnbd_clt_destroy_sysfs_files(void);
 148
 149 void rnbd_clt_remove_dev_symlink(struct rnbd_clt_dev *dev);
 150
 151 #endif /* RNBD_CLT_H */