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 /* Max. number of segments per IO request, Mellanox Connect X ~ Connect X5,
  24  * choose minimial 30 for all, minus 1 for internal protocol, so 29.
  25  */
  26 #define BMAX_SEGMENTS 29
  27 /*  time in seconds between reconnect tries, default to 30 s */
  28 #define RECONNECT_DELAY 30
  29 /*
  30  * Number of times to reconnect on error before giving up, 0 for * disabled,
  31  * -1 for forever
  32  */
  33 #define MAX_RECONNECTS -1
  34
  35 enum rnbd_clt_dev_state {
  36         DEV_STATE_INIT,
  37         DEV_STATE_MAPPED,
  38         DEV_STATE_MAPPED_DISCONNECTED,
  39         DEV_STATE_UNMAPPED,
  40 };
  41
  42 struct rnbd_iu_comp {
  43         wait_queue_head_t wait;
  44         int errno;
  45 };
  46
  47 #ifdef CONFIG_ARCH_NO_SG_CHAIN
  48 #define RNBD_INLINE_SG_CNT 0
  49 #else
  50 #define RNBD_INLINE_SG_CNT 2
  51 #endif
  52 #define RNBD_RDMA_SGL_SIZE (sizeof(struct scatterlist) * RNBD_INLINE_SG_CNT)
  53
  54 struct rnbd_iu {
  55         union {
  56                 struct request *rq; /* for block io */
  57                 void *buf; /* for user messages */
  58         };
  59         struct rtrs_permit      *permit;
  60         union {
  61                 /* use to send msg associated with a dev */
  62                 struct rnbd_clt_dev *dev;
  63                 /* use to send msg associated with a sess */
  64                 struct rnbd_clt_session *sess;
  65         };
  66         struct sg_table         sgt;
  67         struct work_struct      work;
  68         int                     errno;
  69         struct rnbd_iu_comp     comp;
  70         atomic_t                refcount;
  71         struct scatterlist      first_sgl[]; /* must be the last one */
  72 };
  73
  74 struct rnbd_cpu_qlist {
  75         struct list_head        requeue_list;
  76         spinlock_t              requeue_lock;
  77         unsigned int            cpu;
  78 };
  79
  80 struct rnbd_clt_session {
  81         struct list_head        list;
  82         struct rtrs_clt        *rtrs;
  83         wait_queue_head_t       rtrs_waitq;
  84         bool                    rtrs_ready;
  85         struct rnbd_cpu_qlist   __percpu
  86                                 *cpu_queues;
  87         DECLARE_BITMAP(cpu_queues_bm, NR_CPUS);
  88         int     __percpu        *cpu_rr; /* per-cpu var for CPU round-robin */
  89         atomic_t                busy;
  90         int                     queue_depth;
  91         u32                     max_io_size;
  92         struct blk_mq_tag_set   tag_set;
  93         struct mutex            lock; /* protects state and devs_list */
  94         struct list_head        devs_list; /* list of struct rnbd_clt_dev */
  95         refcount_t              refcount;
  96         char                    sessname[NAME_MAX];
  97         u8                      ver; /* protocol version */
  98 };
  99
 100 /**
 101  * Submission queues.
 102  */
 103 struct rnbd_queue {
 104         struct list_head        requeue_list;
 105         unsigned long           in_list;
 106         struct rnbd_clt_dev     *dev;
 107         struct blk_mq_hw_ctx    *hctx;
 108 };
 109
 110 struct rnbd_clt_dev {
 111         struct rnbd_clt_session *sess;
 112         struct request_queue    *queue;
 113         struct rnbd_queue       *hw_queues;
 114         u32                     device_id;
 115         /* local Idr index - used to track minor number allocations. */
 116         u32                     clt_device_id;
 117         struct mutex            lock;
 118         enum rnbd_clt_dev_state dev_state;
 119         char                    *pathname;
 120         enum rnbd_access_mode   access_mode;
 121         bool                    read_only;
 122         bool                    rotational;
 123         bool                    wc;
 124         bool                    fua;
 125         u32                     max_hw_sectors;
 126         u32                     max_write_same_sectors;
 127         u32                     max_discard_sectors;
 128         u32                     discard_granularity;
 129         u32                     discard_alignment;
 130         u16                     secure_discard;
 131         u16                     physical_block_size;
 132         u16                     logical_block_size;
 133         u16                     max_segments;
 134         size_t                  nsectors;
 135         u64                     size;           /* device size in bytes */
 136         struct list_head        list;
 137         struct gendisk          *gd;
 138         struct kobject          kobj;
 139         char                    *blk_symlink_name;
 140         refcount_t              refcount;
 141         struct work_struct      unmap_on_rmmod_work;
 142 };
 143
 144 /* rnbd-clt.c */
 145
 146 struct rnbd_clt_dev *rnbd_clt_map_device(const char *sessname,
 147                                            struct rtrs_addr *paths,
 148                                            size_t path_cnt, u16 port_nr,
 149                                            const char *pathname,
 150                                            enum rnbd_access_mode access_mode);
 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 void rnbd_clt_destroy_default_group(void);
 163
 164 void rnbd_clt_remove_dev_symlink(struct rnbd_clt_dev *dev);
 165
 166 #endif /* RNBD_CLT_H */