+--- a/drivers/mtd/Kconfig
++++ b/drivers/mtd/Kconfig
+@@ -53,6 +53,16 @@ config MTD_TESTS
+ should normally be compiled as kernel modules. The modules perform
+ various checks and verifications when loaded.
+
++config MTD_ROOTFS_ROOT_DEV
++ bool "Automatically set 'rootfs' partition to be root filesystem"
++ depends on MTD_PARTITIONS
++ default y
++
++config MTD_ROOTFS_SPLIT
++ bool "Automatically split 'rootfs' partition for squashfs"
++ depends on MTD_PARTITIONS
++ default y
++
+ config MTD_REDBOOT_PARTS
+ tristate "RedBoot partition table parsing"
+ depends on MTD_PARTITIONS
+--- a/drivers/mtd/mtdpart.c
++++ b/drivers/mtd/mtdpart.c
+@@ -18,6 +18,8 @@
+ #include <linux/mtd/mtd.h>
+ #include <linux/mtd/partitions.h>
+ #include <linux/mtd/compatmac.h>
++#include <linux/root_dev.h>
++#include <linux/magic.h>
+
+ /* Our partition linked list */
+ static LIST_HEAD(mtd_partitions);
+@@ -37,7 +39,7 @@ struct mtd_part {
+ * the pointer to that structure with this macro.
+ */
+ #define PART(x) ((struct mtd_part *)(x))
+-
++#define IS_PART(mtd) (mtd->read == part_read)
+
+ /*
+ * MTD methods which simply translate the effective address and pass through
+@@ -489,6 +491,156 @@ out_register:
+ return slave;
+ }
+
++#ifdef CONFIG_MTD_ROOTFS_SPLIT
++#define ROOTFS_SPLIT_NAME "rootfs_data"
++#define ROOTFS_REMOVED_NAME "<removed>"
++
++struct squashfs_super_block {
++ __le32 s_magic;
++ __le32 pad0[9];
++ __le64 bytes_used;
++};
++
++
++static int split_squashfs(struct mtd_info *master, int offset, int *split_offset)
++{
++ char buf[512];
++ struct squashfs_super_block *sb = (struct squashfs_super_block *) buf;
++ int len, ret;
++
++ ret = master->read(master, offset, sizeof(*sb), &len, buf);
++ if (ret || (len != sizeof(*sb))) {
++ printk(KERN_ALERT "split_squashfs: error occured while reading "
++ "from \"%s\"\n", master->name);
++ return -EINVAL;
++ }
++
++ if (*((u32 *) buf) != SQUASHFS_MAGIC) {
++ printk(KERN_ALERT "split_squashfs: no squashfs found in \"%s\"\n",
++ master->name);
++ *split_offset = 0;
++ return 0;
++ }
++
++ if (sb->bytes_used <= 0) {
++ printk(KERN_ALERT "split_squashfs: squashfs is empty in \"%s\"\n",
++ master->name);
++ *split_offset = 0;
++ return 0;
++ }
++
++ len = (u32) sb->bytes_used;
++ len += (offset & 0x000fffff);
++ len += (master->erasesize - 1);
++ len &= ~(master->erasesize - 1);
++ len -= (offset & 0x000fffff);
++ *split_offset = offset + len;
++
++ return 0;
++}
++
++static int split_rootfs_data(struct mtd_info *master, struct mtd_info *rpart, const struct mtd_partition *part,
++ int index)
++{
++ struct mtd_partition *dpart;
++ struct mtd_part *slave = NULL;
++ int split_offset = 0;
++ int ret;
++
++ ret = split_squashfs(master, part->offset, &split_offset);
++ if (ret)
++ return ret;
++
++ if (split_offset <= 0)
++ return 0;
++
++ dpart = kmalloc(sizeof(*part)+sizeof(ROOTFS_SPLIT_NAME)+1, GFP_KERNEL);
++ if (dpart == NULL) {
++ printk(KERN_INFO "split_squashfs: no memory for partition \"%s\"\n",
++ ROOTFS_SPLIT_NAME);
++ return -ENOMEM;
++ }
++
++ memcpy(dpart, part, sizeof(*part));
++ dpart->name = (unsigned char *)&dpart[1];
++ strcpy(dpart->name, ROOTFS_SPLIT_NAME);
++
++ dpart->size -= split_offset - dpart->offset;
++ dpart->offset = split_offset;
++
++ if (dpart == NULL)
++ return 1;
++
++ printk(KERN_INFO "mtd: partition \"%s\" created automatically, ofs=%llX, len=%llX \n",
++ ROOTFS_SPLIT_NAME, dpart->offset, dpart->size);
++
++ slave = add_one_partition(master, dpart, index, split_offset);
++ if (!slave) {
++ kfree(dpart);
++ return -ENOMEM;
++ }
++ rpart->split = &slave->mtd;
++
++ return 0;
++}
++
++static int refresh_rootfs_split(struct mtd_info *mtd)
++{
++ struct mtd_partition tpart;
++ struct mtd_part *part;
++ char *name;
++ int index = 0;
++ int offset, size;
++ int ret;
++
++ part = PART(mtd);
++
++ /* check for the new squashfs offset first */
++ ret = split_squashfs(part->master, part->offset, &offset);
++ if (ret)
++ return ret;
++
++ if ((offset > 0) && !mtd->split) {
++ printk(KERN_INFO "%s: creating new split partition for \"%s\"\n", __func__, mtd->name);
++ /* if we don't have a rootfs split partition, create a new one */
++ tpart.name = (char *) mtd->name;
++ tpart.size = mtd->size;
++ tpart.offset = part->offset;
++
++ /* find the index of the last partition */
++ if (!list_empty(&mtd_partitions))
++ index = list_first_entry(&mtd_partitions, struct mtd_part, list)->index + 1;
++
++ return split_rootfs_data(part->master, &part->mtd, &tpart, index);
++ } else if ((offset > 0) && mtd->split) {
++ /* update the offsets of the existing partition */
++ size = mtd->size + part->offset - offset;
++
++ part = PART(mtd->split);
++ part->offset = offset;
++ part->mtd.size = size;
++ printk(KERN_INFO "%s: %s partition \"" ROOTFS_SPLIT_NAME "\", offset: 0x%06x (0x%06x)\n",
++ __func__, (!strcmp(part->mtd.name, ROOTFS_SPLIT_NAME) ? "updating" : "creating"),
++ (u32) part->offset, (u32) part->mtd.size);
++ name = kmalloc(sizeof(ROOTFS_SPLIT_NAME) + 1, GFP_KERNEL);
++ strcpy(name, ROOTFS_SPLIT_NAME);
++ part->mtd.name = name;
++ } else if ((offset <= 0) && mtd->split) {
++ printk(KERN_INFO "%s: removing partition \"%s\"\n", __func__, mtd->split->name);
++
++ /* mark existing partition as removed */
++ part = PART(mtd->split);
++ name = kmalloc(sizeof(ROOTFS_SPLIT_NAME) + 1, GFP_KERNEL);
++ strcpy(name, ROOTFS_REMOVED_NAME);
++ part->mtd.name = name;
++ part->offset = 0;
++ part->mtd.size = 0;
++ }
++
++ return 0;
++}
++#endif /* CONFIG_MTD_ROOTFS_SPLIT */
++
+ /*
+ * This function, given a master MTD object and a partition table, creates
+ * and registers slave MTD objects which are bound to the master according to
+@@ -502,14 +654,29 @@ int add_mtd_partitions(struct mtd_info *
+ {
+ struct mtd_part *slave;
+ uint64_t cur_offset = 0;
+- int i;
++ int i, j, ret;
+
+ printk(KERN_NOTICE "Creating %d MTD partitions on \"%s\":\n", nbparts, master->name);
+
+- for (i = 0; i < nbparts; i++) {
+- slave = add_one_partition(master, parts + i, i, cur_offset);
++ for (i = 0, j = 0; i < nbparts; i++) {
++ slave = add_one_partition(master, parts + i, j++, cur_offset);
+ if (!slave)
+ return -ENOMEM;
++
++ if (!strcmp(parts[i].name, "rootfs") && slave->registered) {
++#ifdef CONFIG_MTD_ROOTFS_ROOT_DEV
++ if (ROOT_DEV == 0) {
++ printk(KERN_NOTICE "mtd: partition \"rootfs\" "
++ "set to be root filesystem\n");
++ ROOT_DEV = MKDEV(MTD_BLOCK_MAJOR, slave->mtd.index);
++ }
++#endif
++#ifdef CONFIG_MTD_ROOTFS_SPLIT
++ ret = split_rootfs_data(master, &slave->mtd, &parts[i], j);
++ if (ret == 0)
++ j++;
++#endif
++ }
+ cur_offset = slave->offset + slave->mtd.size;
+ }
+
+@@ -517,6 +684,32 @@ int add_mtd_partitions(struct mtd_info *
+ }
+ EXPORT_SYMBOL(add_mtd_partitions);
+
++int refresh_mtd_partitions(struct mtd_info *mtd)
++{
++ int ret = 0;
++
++ if (IS_PART(mtd)) {
++ struct mtd_part *part;
++ struct mtd_info *master;
++
++ part = PART(mtd);
++ master = part->master;
++ if (master->refresh_device)
++ ret = master->refresh_device(master);
++ }
++
++ if (!ret && mtd->refresh_device)
++ ret = mtd->refresh_device(mtd);
++
++#ifdef CONFIG_MTD_ROOTFS_SPLIT
++ if (!ret && IS_PART(mtd) && !strcmp(mtd->name, "rootfs"))
++ refresh_rootfs_split(mtd);
++#endif
++
++ return 0;
++}
++EXPORT_SYMBOL_GPL(refresh_mtd_partitions);
++
+ static DEFINE_SPINLOCK(part_parser_lock);
+ static LIST_HEAD(part_parsers);
+
+--- a/drivers/mtd/devices/block2mtd.c
++++ b/drivers/mtd/devices/block2mtd.c
+@@ -29,6 +29,8 @@ struct block2mtd_dev {
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