partitions.h 3.9 KB

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