target/linux/generic/pending-4.9/401-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 @@ -733,6 +737,36 @@ 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_partition *parts;
  31 +       int nr_parts;
  32 +       int i;
  33 +
  34 +       nr_parts = parse_mtd_partitions_by_type(&slave->mtd, type, (const struct mtd_partition **)&parts,
  35 +                                               NULL);
  36 +       if (nr_parts <= 0)
  37 +               return nr_parts;
  38 +
  39 +       if (WARN_ON(!parts))
  40 +               return 0;
  41 +
  42 +       for (i = 0; i < nr_parts; i++) {
  43 +               /* adjust partition offsets */
  44 +               parts[i].offset += slave->offset;
  45 +
  46 +               mtd_add_partition(slave->parent,
  47 +                                 parts[i].name,
  48 +                                 parts[i].offset,
  49 +                                 parts[i].size);
  50 +       }
  51 +
  52 +       kfree(parts);
  53 +
  54 +       return nr_parts;
  55 +}
  56 +
  57  #ifdef CONFIG_MTD_SPLIT_FIRMWARE_NAME
  58  #define SPLIT_FIRMWARE_NAME    CONFIG_MTD_SPLIT_FIRMWARE_NAME
  59  #else
  60 @@ -1109,6 +1143,61 @@ void mtd_part_parser_cleanup(struct mtd_
  61         }
  62  }
  63
  64 +static struct mtd_part_parser *
  65 +get_partition_parser_by_type(enum mtd_parser_type type,
  66 +                            struct mtd_part_parser *start)
  67 +{
  68 +       struct mtd_part_parser *p, *ret = NULL;
  69 +
  70 +       spin_lock(&part_parser_lock);
  71 +
  72 +       p = list_prepare_entry(start, &part_parsers, list);
  73 +       if (start)
  74 +               mtd_part_parser_put(start);
  75 +
  76 +       list_for_each_entry_continue(p, &part_parsers, list) {
  77 +               if (p->type == type && try_module_get(p->owner)) {
  78 +                       ret = p;
  79 +                       break;
  80 +               }
  81 +       }
  82 +
  83 +       spin_unlock(&part_parser_lock);
  84 +
  85 +       return ret;
  86 +}
  87 +
  88 +static int parse_mtd_partitions_by_type(struct mtd_info *master,
  89 +                                       enum mtd_parser_type type,
  90 +                                       const struct mtd_partition **pparts,
  91 +                                       struct mtd_part_parser_data *data)
  92 +{
  93 +       struct mtd_part_parser *prev = NULL;
  94 +       int ret = 0;
  95 +
  96 +       while (1) {
  97 +               struct mtd_part_parser *parser;
  98 +
  99 +               parser = get_partition_parser_by_type(type, prev);
 100 +               if (!parser)
 101 +                       break;
 102 +
 103 +               ret = (*parser->parse_fn)(master, pparts, data);
 104 +
 105 +               if (ret > 0) {
 106 +                       mtd_part_parser_put(parser);
 107 +                       printk(KERN_NOTICE
 108 +                              "%d %s partitions found on MTD device %s\n",
 109 +                              ret, parser->name, master->name);
 110 +                       break;
 111 +               }
 112 +
 113 +               prev = parser;
 114 +       }
 115 +
 116 +       return ret;
 117 +}
 118 +
 119  int mtd_is_partition(const struct mtd_info *mtd)
 120  {
 121         struct mtd_part *part;
 122 --- a/include/linux/mtd/partitions.h
 123 +++ b/include/linux/mtd/partitions.h
 124 @@ -73,6 +73,10 @@ struct mtd_part_parser_data {
 125   * Functions dealing with the various ways of partitioning the space
 126   */
 127
 128 +enum mtd_parser_type {
 129 +       MTD_PARSER_TYPE_DEVICE = 0,
 130 +};
 131 +
 132  struct mtd_part_parser {
 133         struct list_head list;
 134         struct module *owner;
 135 @@ -81,6 +85,7 @@ struct mtd_part_parser {
 136         int (*parse_fn)(struct mtd_info *, const struct mtd_partition **,
 137                         struct mtd_part_parser_data *);
 138         void (*cleanup)(const struct mtd_partition *pparts, int nr_parts);
 139 +       enum mtd_parser_type type;
 140  };
 141
 142  /* Container for passing around a set of parsed partitions */