include/linux/mtd/blktrans.h

   1 /* SPDX-License-Identifier: GPL-2.0-or-later */
   2 /*
   3  * Copyright © 2003-2010 David Woodhouse <dwmw2@infradead.org>
   4  */
   5
   6 #ifndef __MTD_TRANS_H__
   7 #define __MTD_TRANS_H__
   8
   9 #include <linux/mutex.h>
  10 #include <linux/kref.h>
  11 #include <linux/sysfs.h>
  12
  13 struct hd_geometry;
  14 struct mtd_info;
  15 struct mtd_blktrans_ops;
  16 struct file;
  17 struct inode;
  18
  19 struct mtd_blktrans_dev {
  20         struct mtd_blktrans_ops *tr;
  21         struct list_head list;
  22         struct mtd_info *mtd;
  23         struct mutex lock;
  24         int devnum;
  25         bool bg_stop;
  26         unsigned long size;
  27         int readonly;
  28         int open;
  29         struct kref ref;
  30         struct gendisk *disk;
  31         struct attribute_group *disk_attributes;
  32         struct request_queue *rq;
  33         struct list_head rq_list;
  34         struct blk_mq_tag_set *tag_set;
  35         spinlock_t queue_lock;
  36         void *priv;
  37         bool writable;
  38 };
  39
  40 struct mtd_blktrans_ops {
  41         char *name;
  42         int major;
  43         int part_bits;
  44         int blksize;
  45         int blkshift;
  46
  47         /* Access functions */
  48         int (*readsect)(struct mtd_blktrans_dev *dev,
  49                     unsigned long block, char *buffer);
  50         int (*writesect)(struct mtd_blktrans_dev *dev,
  51                      unsigned long block, char *buffer);
  52         int (*discard)(struct mtd_blktrans_dev *dev,
  53                        unsigned long block, unsigned nr_blocks);
  54         void (*background)(struct mtd_blktrans_dev *dev);
  55
  56         /* Block layer ioctls */
  57         int (*getgeo)(struct mtd_blktrans_dev *dev, struct hd_geometry *geo);
  58         int (*flush)(struct mtd_blktrans_dev *dev);
  59
  60         /* Called with mtd_table_mutex held; no race with add/remove */
  61         int (*open)(struct mtd_blktrans_dev *dev);
  62         void (*release)(struct mtd_blktrans_dev *dev);
  63
  64         /* Called on {de,}registration and on subsequent addition/removal
  65            of devices, with mtd_table_mutex held. */
  66         void (*add_mtd)(struct mtd_blktrans_ops *tr, struct mtd_info *mtd);
  67         void (*remove_dev)(struct mtd_blktrans_dev *dev);
  68
  69         struct list_head devs;
  70         struct list_head list;
  71         struct module *owner;
  72 };
  73
  74 extern int register_mtd_blktrans(struct mtd_blktrans_ops *tr);
  75 extern int deregister_mtd_blktrans(struct mtd_blktrans_ops *tr);
  76 extern int add_mtd_blktrans_dev(struct mtd_blktrans_dev *dev);
  77 extern int del_mtd_blktrans_dev(struct mtd_blktrans_dev *dev);
  78 extern int mtd_blktrans_cease_background(struct mtd_blktrans_dev *dev);
  79
  80 /**
  81  * module_mtd_blktrans() - Helper macro for registering a mtd blktrans driver
  82  * @__mtd_blktrans: mtd_blktrans_ops struct
  83  *
  84  * Helper macro for mtd blktrans drivers which do not do anything special in
  85  * module init/exit. This eliminates a lot of boilerplate. Each module may only
  86  * use this macro once, and calling it replaces module_init() and module_exit()
  87  */
  88 #define module_mtd_blktrans(__mtd_blktrans) \
  89         module_driver(__mtd_blktrans, register_mtd_blktrans, \
  90                                         deregister_mtd_blktrans)
  91
  92 #endif /* __MTD_TRANS_H__ */