target/linux/generic/pending-4.14/401-mtd-add-support-for-different-partition-parser-types.patch

   1 From: Gabor Juhos <juhosg@openwrt.org>
   2 Subject: mtd: add support for different partition parser types
   3
   4 Signed-off-by: Gabor Juhos <juhosg@openwrt.org>
   5 ---
   6  drivers/mtd/mtdpart.c          |   56 ++++++++++++++++++++++++++++++++++++++++
   7  include/linux/mtd/partitions.h |   11 ++++++++
   8  2 files changed, 67 insertions(+)
   9
  10 --- a/drivers/mtd/mtdpart.c
  11 +++ b/drivers/mtd/mtdpart.c
  12 @@ -56,6 +56,10 @@ struct mtd_part {
  13  };
  14
  15  static void mtd_partition_split(struct mtd_info *master, struct mtd_part *part);
  16 +static int parse_mtd_partitions_by_type(struct mtd_info *master,
  17 +                                       enum mtd_parser_type type,
  18 +                                       const struct mtd_partition **pparts,
  19 +                                       struct mtd_part_parser_data *data);
  20
  21  /*
  22   * Given a pointer to the MTD object in the mtd_part structure, we can retrieve
  23 @@ -762,6 +766,27 @@ int mtd_del_partition(struct mtd_info *m
  24  }
  25  EXPORT_SYMBOL_GPL(mtd_del_partition);
  26
  27 +static int
  28 +run_parsers_by_type(struct mtd_part *slave, enum mtd_parser_type type)
  29 +{
  30 +       struct mtd_partitions pparts = { };
  31 +       int err;
  32 +
  33 +       pparts.nr_parts = parse_mtd_partitions_by_type(&slave->mtd, type,
  34 +                                                      &pparts.parts, NULL);
  35 +       if (pparts.nr_parts <= 0)
  36 +               return pparts.nr_parts;
  37 +
  38 +       if (WARN_ON(!pparts.parts))
  39 +               return 0;
  40 +
  41 +       err = add_mtd_partitions(&slave->mtd, pparts.parts, pparts.nr_parts);
  42 +
  43 +       kfree(pparts.parts);
  44 +
  45 +       return err ? err : pparts.nr_parts;
  46 +}
  47 +
  48  #ifdef CONFIG_MTD_SPLIT_FIRMWARE_NAME
  49  #define SPLIT_FIRMWARE_NAME    CONFIG_MTD_SPLIT_FIRMWARE_NAME
  50  #else
  51 @@ -1147,6 +1172,61 @@ void mtd_part_parser_cleanup(struct mtd_
  52         }
  53  }
  54
  55 +static struct mtd_part_parser *
  56 +get_partition_parser_by_type(enum mtd_parser_type type,
  57 +                            struct mtd_part_parser *start)
  58 +{
  59 +       struct mtd_part_parser *p, *ret = NULL;
  60 +
  61 +       spin_lock(&part_parser_lock);
  62 +
  63 +       p = list_prepare_entry(start, &part_parsers, list);
  64 +       if (start)
  65 +               mtd_part_parser_put(start);
  66 +
  67 +       list_for_each_entry_continue(p, &part_parsers, list) {
  68 +               if (p->type == type && try_module_get(p->owner)) {
  69 +                       ret = p;
  70 +                       break;
  71 +               }
  72 +       }
  73 +
  74 +       spin_unlock(&part_parser_lock);
  75 +
  76 +       return ret;
  77 +}
  78 +
  79 +static int parse_mtd_partitions_by_type(struct mtd_info *master,
  80 +                                       enum mtd_parser_type type,
  81 +                                       const struct mtd_partition **pparts,
  82 +                                       struct mtd_part_parser_data *data)
  83 +{
  84 +       struct mtd_part_parser *prev = NULL;
  85 +       int ret = 0;
  86 +
  87 +       while (1) {
  88 +               struct mtd_part_parser *parser;
  89 +
  90 +               parser = get_partition_parser_by_type(type, prev);
  91 +               if (!parser)
  92 +                       break;
  93 +
  94 +               ret = (*parser->parse_fn)(master, pparts, data);
  95 +
  96 +               if (ret > 0) {
  97 +                       mtd_part_parser_put(parser);
  98 +                       printk(KERN_NOTICE
  99 +                              "%d %s partitions found on MTD device %s\n",
 100 +                              ret, parser->name, master->name);
 101 +                       break;
 102 +               }
 103 +
 104 +               prev = parser;
 105 +       }
 106 +
 107 +       return ret;
 108 +}
 109 +
 110  int mtd_is_partition(const struct mtd_info *mtd)
 111  {
 112         struct mtd_part *part;
 113 --- a/include/linux/mtd/partitions.h
 114 +++ b/include/linux/mtd/partitions.h
 115 @@ -73,6 +73,10 @@ struct mtd_part_parser_data {
 116   * Functions dealing with the various ways of partitioning the space
 117   */
 118
 119 +enum mtd_parser_type {
 120 +       MTD_PARSER_TYPE_DEVICE = 0,
 121 +};
 122 +
 123  struct mtd_part_parser {
 124         struct list_head list;
 125         struct module *owner;
 126 @@ -81,6 +85,7 @@ struct mtd_part_parser {
 127         int (*parse_fn)(struct mtd_info *, const struct mtd_partition **,
 128                         struct mtd_part_parser_data *);
 129         void (*cleanup)(const struct mtd_partition *pparts, int nr_parts);
 130 +       enum mtd_parser_type type;
 131  };
 132
 133  /* Container for passing around a set of parsed partitions */