target/linux/generic/pending-5.4/400-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 @@ -15,10 +15,12 @@
  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/err.h>
  46  #include <linux/of.h>
  47
  48  #include "mtdcore.h"
  49 +#include "mtdsplit/mtdsplit.h"
  50
  51  /* Our partition linked list */
  52  static LIST_HEAD(mtd_partitions);
  53 @@ -38,6 +40,8 @@ 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 @@ -612,6 +616,7 @@ int mtd_add_partition(struct mtd_info *p
  63         if (ret)
  64                 goto err_remove_part;
  65
  66 +       mtd_partition_split(parent, new);
  67         mtd_add_partition_attrs(new);
  68
  69         return 0;
  70 @@ -698,6 +703,29 @@ 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 +static void mtd_partition_split(struct mtd_info *master, struct mtd_part *part)
  85 +{
  86 +       static int rootfs_found = 0;
  87 +
  88 +       if (rootfs_found)
  89 +               return;
  90 +
  91 +       if (IS_ENABLED(CONFIG_MTD_SPLIT_FIRMWARE) &&
  92 +           !strcmp(part->mtd.name, SPLIT_FIRMWARE_NAME) &&
  93 +           !of_find_property(mtd_get_of_node(&part->mtd), "compatible", NULL))
  94 +               split_firmware(master, part);
  95 +}
  96 +
  97  /*
  98   * This function, given a master MTD object and a partition table, creates
  99   * and registers slave MTD objects which are bound to the master according to
 100 @@ -738,6 +766,7 @@ int add_mtd_partitions(struct mtd_info *
 101                         goto err_del_partitions;
 102                 }
 103
 104 +               mtd_partition_split(master, slave);
 105                 mtd_add_partition_attrs(slave);
 106                 /* Look for subpartitions */
 107                 parse_mtd_partitions(&slave->mtd, parts[i].types, NULL);