target/linux/generic/pending-4.9/400-mtd-add-rootfs-split-support.patch

   1 From: Felix Fietkau <nbd@nbd.name>
   2 Subject: make rootfs split/detection more generic - patch can be moved to generic-2.6 after testing on other platforms
   3
   4 lede-commit: 328e660b31f0937d52c5ae3d6e7029409918a9df
   5 Signed-off-by: Felix Fietkau <nbd@nbd.name>
   6 ---
   7  drivers/mtd/Kconfig            | 17 +++++++++++++++++
   8  drivers/mtd/mtdpart.c          | 35 +++++++++++++++++++++++++++++++++++
   9  include/linux/mtd/partitions.h |  2 ++
  10  3 files changed, 54 insertions(+)
  11
  12 --- a/drivers/mtd/Kconfig
  13 +++ b/drivers/mtd/Kconfig
  14 @@ -12,6 +12,23 @@ menuconfig MTD
  15
  16  if MTD
  17
  18 +menu "OpenWrt specific MTD options"
  19 +
  20 +config MTD_ROOTFS_ROOT_DEV
  21 +       bool "Automatically set 'rootfs' partition to be root filesystem"
  22 +       default y
  23 +
  24 +config MTD_SPLIT_FIRMWARE
  25 +       bool "Automatically split firmware partition for kernel+rootfs"
  26 +       default y
  27 +
  28 +config MTD_SPLIT_FIRMWARE_NAME
  29 +       string "Firmware partition name"
  30 +       depends on MTD_SPLIT_FIRMWARE
  31 +       default "firmware"
  32 +
  33 +endmenu
  34 +
  35  config MTD_TESTS
  36         tristate "MTD tests support (DANGEROUS)"
  37         depends on m
  38 --- a/drivers/mtd/mtdpart.c
  39 +++ b/drivers/mtd/mtdpart.c
  40 @@ -29,10 +29,12 @@
  41  #include <linux/kmod.h>
  42  #include <linux/mtd/mtd.h>
  43  #include <linux/mtd/partitions.h>
  44 +#include <linux/magic.h>
  45  #include <linux/of.h>
  46  #include <linux/err.h>
  47
  48  #include "mtdcore.h"
  49 +#include "mtdsplit/mtdsplit.h"
  50
  51  /* Our partition linked list */
  52  static LIST_HEAD(mtd_partitions);
  53 @@ -52,6 +54,8 @@ struct mtd_part {
  54         struct list_head list;
  55  };
  56
  57 +static void mtd_partition_split(struct mtd_info *master, struct mtd_part *part);
  58 +
  59  /*
  60   * Given a pointer to the MTD object in the mtd_part structure, we can retrieve
  61   * the pointer to that structure.
  62 @@ -678,6 +682,7 @@ int mtd_add_partition(struct mtd_info *p
  63         mutex_unlock(&mtd_partitions_mutex);
  64
  65         add_mtd_device(&new->mtd);
  66 +       mtd_partition_split(parent, new);
  67
  68         mtd_add_partition_attrs(new);
  69
  70 @@ -756,6 +761,35 @@ int mtd_del_partition(struct mtd_info *m
  71  }
  72  EXPORT_SYMBOL_GPL(mtd_del_partition);
  73
  74 +#ifdef CONFIG_MTD_SPLIT_FIRMWARE_NAME
  75 +#define SPLIT_FIRMWARE_NAME    CONFIG_MTD_SPLIT_FIRMWARE_NAME
  76 +#else
  77 +#define SPLIT_FIRMWARE_NAME    "unused"
  78 +#endif
  79 +
  80 +static void split_firmware(struct mtd_info *master, struct mtd_part *part)
  81 +{
  82 +}
  83 +
  84 +void __weak arch_split_mtd_part(struct mtd_info *master, const char *name,
  85 +                                int offset, int size)
  86 +{
  87 +}
  88 +
  89 +static void mtd_partition_split(struct mtd_info *master, struct mtd_part *part)
  90 +{
  91 +       static int rootfs_found = 0;
  92 +
  93 +       if (rootfs_found)
  94 +               return;
  95 +
  96 +       if (!strcmp(part->mtd.name, SPLIT_FIRMWARE_NAME) &&
  97 +           IS_ENABLED(CONFIG_MTD_SPLIT_FIRMWARE))
  98 +               split_firmware(master, part);
  99 +
 100 +       arch_split_mtd_part(master, part->mtd.name, part->offset,
 101 +                           part->mtd.size);
 102 +}
 103  /*
 104   * This function, given a master MTD object and a partition table, creates
 105   * and registers slave MTD objects which are bound to the master according to
 106 @@ -787,6 +821,7 @@ int add_mtd_partitions(struct mtd_info *
 107                 mutex_unlock(&mtd_partitions_mutex);
 108
 109                 add_mtd_device(&slave->mtd);
 110 +               mtd_partition_split(master, slave);
 111                 mtd_add_partition_attrs(slave);
 112                 if (parts[i].types)
 113                         mtd_parse_part(slave, parts[i].types);
 114 --- a/include/linux/mtd/partitions.h
 115 +++ b/include/linux/mtd/partitions.h
 116 @@ -109,5 +109,7 @@ int mtd_add_partition(struct mtd_info *m
 117                       long long offset, long long length);
 118  int mtd_del_partition(struct mtd_info *master, int partno);
 119  uint64_t mtd_get_device_size(const struct mtd_info *mtd);
 120 +extern void __weak arch_split_mtd_part(struct mtd_info *master,
 121 +                                      const char *name, int offset, int size);
 122
 123  #endif