LXR linux/include/linux/mtd/partitions.h

   1/*
   2 * MTD partitioning layer definitions
   3 *
   4 * (C) 2000 Nicolas Pitre <nico@fluxnic.net>
   5 *
   6 * This code is GPL
   7 */
   8
   9#ifndef MTD_PARTITIONS_H
  10#define MTD_PARTITIONS_H
  11
  12#include <linux/types.h>
  13
  14
  15/*
  16 * Partition definition structure:
  17 *
  18 * An array of struct partition is passed along with a MTD object to
  19 * mtd_device_register() to create them.
  20 *
  21 * For each partition, these fields are available:
  22 * name: string that will be used to label the partition's MTD device.
  23 * size: the partition size; if defined as MTDPART_SIZ_FULL, the partition
  24 *      will extend to the end of the master MTD device.
  25 * offset: absolute starting position within the master MTD device; if
  26 *      defined as MTDPART_OFS_APPEND, the partition will start where the
  27 *      previous one ended; if MTDPART_OFS_NXTBLK, at the next erase block;
  28 *      if MTDPART_OFS_RETAIN, consume as much as possible, leaving size
  29 *      after the end of partition.
  30 * mask_flags: contains flags that have to be masked (removed) from the
  31 *      master MTD flag set for the corresponding MTD partition.
  32 *      For example, to force a read-only partition, simply adding
  33 *      MTD_WRITEABLE to the mask_flags will do the trick.
  34 *
  35 * Note: writeable partitions require their size and offset be
  36 * erasesize aligned (e.g. use MTDPART_OFS_NEXTBLK).
  37 */
  38
  39struct mtd_partition {
  40        const char *name;               /* identifier string */
  41        uint64_t size;                  /* partition size */
  42        uint64_t offset;                /* offset within the master MTD space */
  43        uint32_t mask_flags;            /* master MTD flags to mask out for this partition */
  44};
  45
  46#define MTDPART_OFS_RETAIN      (-3)
  47#define MTDPART_OFS_NXTBLK      (-2)
  48#define MTDPART_OFS_APPEND      (-1)
  49#define MTDPART_SIZ_FULL        (0)
  50
  51
  52struct mtd_info;
  53struct device_node;
  54
  55/**
  56 * struct mtd_part_parser_data - used to pass data to MTD partition parsers.
  57 * @origin: for RedBoot, start address of MTD device
  58 */
  59struct mtd_part_parser_data {
  60        unsigned long origin;
  61};
  62
  63
  64/*
  65 * Functions dealing with the various ways of partitioning the space
  66 */
  67
  68struct mtd_part_parser {
  69        struct list_head list;
  70        struct module *owner;
  71        const char *name;
  72        int (*parse_fn)(struct mtd_info *, const struct mtd_partition **,
  73                        struct mtd_part_parser_data *);
  74        void (*cleanup)(const struct mtd_partition *pparts, int nr_parts);
  75};
  76
  77/* Container for passing around a set of parsed partitions */
  78struct mtd_partitions {
  79        const struct mtd_partition *parts;
  80        int nr_parts;
  81        const struct mtd_part_parser *parser;
  82};
  83
  84extern int __register_mtd_parser(struct mtd_part_parser *parser,
  85                                 struct module *owner);
  86#define register_mtd_parser(parser) __register_mtd_parser(parser, THIS_MODULE)
  87
  88extern void deregister_mtd_parser(struct mtd_part_parser *parser);
  89
  90/*
  91 * module_mtd_part_parser() - Helper macro for MTD partition parsers that don't
  92 * do anything special in module init/exit. Each driver may only use this macro
  93 * once, and calling it replaces module_init() and module_exit().
  94 */
  95#define module_mtd_part_parser(__mtd_part_parser) \
  96        module_driver(__mtd_part_parser, register_mtd_parser, \
  97                      deregister_mtd_parser)
  98
  99int mtd_is_partition(const struct mtd_info *mtd);
 100int mtd_add_partition(struct mtd_info *master, const char *name,
 101                      long long offset, long long length);
 102int mtd_del_partition(struct mtd_info *master, int partno);
 103uint64_t mtd_get_device_size(const struct mtd_info *mtd);
 104
 105#endif
 106