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|
--- a/drivers/mtd/Kconfig
+++ b/drivers/mtd/Kconfig
@@ -23,6 +23,14 @@ config MTD_TESTS
WARNING: some of the tests will ERASE entire MTD device which they
test. Do not use these tests unless you really know what you do.
+config MTD_ROOTFS_ROOT_DEV
+ bool "Automatically set 'rootfs' partition to be root filesystem"
+ default y
+
+config MTD_ROOTFS_SPLIT
+ bool "Automatically split 'rootfs' partition for squashfs"
+ default y
+
config MTD_REDBOOT_PARTS
tristate "RedBoot partition table parsing"
---help---
--- a/drivers/mtd/mtdpart.c
+++ b/drivers/mtd/mtdpart.c
@@ -29,6 +29,8 @@
#include <linux/kmod.h>
#include <linux/mtd/mtd.h>
#include <linux/mtd/partitions.h>
+#include <linux/root_dev.h>
+#include <linux/magic.h>
#include <linux/err.h>
#include "mtdcore.h"
@@ -50,7 +52,7 @@ 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
@@ -613,6 +615,92 @@ int mtd_del_partition(struct mtd_info *m
}
EXPORT_SYMBOL_GPL(mtd_del_partition);
+#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)
+{
+ struct squashfs_super_block sb;
+ int len, ret;
+
+ ret = mtd_read(master, offset, sizeof(sb), &len, (void *) &sb);
+ if (ret || (len != sizeof(sb))) {
+ printk(KERN_ALERT "split_squashfs: error occured while reading "
+ "from \"%s\"\n", master->name);
+ return -EINVAL;
+ }
+
+ if (SQUASHFS_MAGIC != le32_to_cpu(sb.s_magic) ) {
+ printk(KERN_ALERT "split_squashfs: no squashfs found in \"%s\"\n",
+ master->name);
+ *split_offset = 0;
+ return 0;
+ }
+
+ if (le64_to_cpu((sb.bytes_used)) <= 0) {
+ printk(KERN_ALERT "split_squashfs: squashfs is empty in \"%s\"\n",
+ master->name);
+ *split_offset = 0;
+ return 0;
+ }
+
+ len = (u32) le64_to_cpu(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)
+{
+ struct mtd_partition dpart;
+ struct mtd_part *slave = NULL;
+ struct mtd_part *spart;
+ int ret, split_offset = 0;
+
+ spart = PART(rpart);
+ ret = split_squashfs(master, spart->offset, &split_offset);
+ if (ret)
+ return ret;
+
+ if (split_offset <= 0)
+ return 0;
+
+ memcpy(&dpart, part, sizeof(dpart));
+ dpart.name = ROOTFS_SPLIT_NAME;
+
+ dpart.size = rpart->size - (split_offset - spart->offset);
+ dpart.offset = split_offset;
+
+ printk(KERN_INFO "mtd: partition \"%s\" created automatically, ofs=%llX, len=%llX \n",
+ ROOTFS_SPLIT_NAME, dpart.offset, dpart.size);
+
+ slave = allocate_partition(master, &dpart, 0, split_offset);
+ if (IS_ERR(slave))
+ return PTR_ERR(slave);
+ mutex_lock(&mtd_partitions_mutex);
+ list_add(&slave->list, &mtd_partitions);
+ mutex_unlock(&mtd_partitions_mutex);
+
+ add_mtd_device(&slave->mtd);
+
+ rpart->split = &slave->mtd;
+
+ 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
@@ -629,6 +717,9 @@ int add_mtd_partitions(struct mtd_info *
struct mtd_part *slave;
uint64_t cur_offset = 0;
int i;
+#ifdef CONFIG_MTD_ROOTFS_SPLIT
+ int ret;
+#endif
printk(KERN_NOTICE "Creating %d MTD partitions on \"%s\":\n", nbparts, master->name);
@@ -643,6 +734,21 @@ int add_mtd_partitions(struct mtd_info *
add_mtd_device(&slave->mtd);
+ if (!strcmp(parts[i].name, "rootfs")) {
+#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]);
+ /* if (ret == 0)
+ * j++; */
+#endif
+ }
+
cur_offset = slave->offset + slave->mtd.size;
}
--- a/include/linux/mtd/mtd.h
+++ b/include/linux/mtd/mtd.h
@@ -114,6 +114,7 @@ struct nand_ecclayout {
struct module; /* only needed for owner field in mtd_info */
+struct mtd_info;
struct mtd_info {
u_char type;
uint32_t flags;
@@ -226,6 +227,8 @@ struct mtd_info {
int (*_block_markbad) (struct mtd_info *mtd, loff_t ofs);
int (*_suspend) (struct mtd_info *mtd);
void (*_resume) (struct mtd_info *mtd);
+ struct mtd_info *split;
+
/*
* If the driver is something smart, like UBI, it may need to maintain
* its own reference counting. The below functions are only for driver.
|
