kernel: implement automatic rootfs split from the firmware partition in linux 3.10 (disabled by default)

Signed-off-by: Felix Fietkau <nbd@openwrt.org> SVN-Revision: 37283
2013-07-14 12:57:03 +00:00 · 2013-07-14 12:57:03 +00:00 · 656d475043
commit 656d475043
parent b95bdc8ab5
2 changed files with 184 additions and 81 deletions
--- a/target/linux/generic/config-3.10
+++ b/target/linux/generic/config-3.10
@ -1840,6 +1840,8 @@ CONFIG_MTD_ROOTFS_SPLIT=y
 # CONFIG_MTD_SWAP is not set
 # CONFIG_MTD_TESTS is not set
 # CONFIG_MTD_UBI is not set
+# CONFIG_MTD_UIMAGE_SPLIT is not set
+CONFIG_MTD_UIMAGE_SPLIT_NAME="firmware"
 # CONFIG_MUTEX_SPIN_ON_OWNER is not set
 # CONFIG_MV643XX_ETH is not set
 # CONFIG_MVMDIO is not set
--- a/target/linux/generic/patches-3.10/400-rootfs_split.patch
+++ b/target/linux/generic/patches-3.10/400-rootfs_split.patch
@ -1,6 +1,6 @@
 --- a/drivers/mtd/Kconfig
 +++ b/drivers/mtd/Kconfig
-@@ -23,6 +23,14 @@ config MTD_TESTS
+@@ -23,6 +23,23 @@ 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.
 
@ -11,6 +11,15 @@
 +config MTD_ROOTFS_SPLIT
 +	bool "Automatically split 'rootfs' partition for squashfs"
 +	default y
+
+config MTD_UIMAGE_SPLIT
+	bool "Automatically split off rootfs from a kernel partition containing a uImage"
+	default y
+
+config MTD_UIMAGE_SPLIT_NAME
+	string "uImage partition name"
+	depends on MTD_UIMAGE_SPLIT
+	default "firmware"
 +
 config MTD_REDBOOT_PARTS
 	tristate "RedBoot partition table parsing"
@ -26,7 +35,14 @@
 #include <linux/err.h>
 
 #include "mtdcore.h"
-@@ -50,7 +52,7 @@ struct mtd_part {
+@@ -45,12 +47,14 @@ struct mtd_part {
+ 	struct list_head list;
+ };
+ 
+static void mtd_partition_split(struct mtd_info *master, struct mtd_part *part);
+
+ /*
+  * Given a pointer to the MTD object in the mtd_part structure, we can retrieve
  * the pointer to that structure with this macro.
  */
 #define PART(x)  ((struct mtd_part *)(x))
@ -35,10 +51,82 @@
 
 /*
  * MTD methods which simply translate the effective address and pass through
-@@ -613,6 +615,92 @@ int mtd_del_partition(struct mtd_info *m
+@@ -533,8 +537,10 @@ out_register:
+ 	return slave;
+ }
+ 
+-int mtd_add_partition(struct mtd_info *master, char *name,
+-		      long long offset, long long length)
+
+static int
+__mtd_add_partition(struct mtd_info *master, char *name,
+		    long long offset, long long length, bool dup_check)
+ {
+ 	struct mtd_partition part;
+ 	struct mtd_part *p, *new;
+@@ -566,21 +572,24 @@ int mtd_add_partition(struct mtd_info *m
+ 	end = offset + length;
+ 
+ 	mutex_lock(&mtd_partitions_mutex);
+-	list_for_each_entry(p, &mtd_partitions, list)
+-		if (p->master == master) {
+-			if ((start >= p->offset) &&
+-			    (start < (p->offset + p->mtd.size)))
+-				goto err_inv;
+-
+-			if ((end >= p->offset) &&
+-			    (end < (p->offset + p->mtd.size)))
+-				goto err_inv;
+-		}
+	if (dup_check) {
+		list_for_each_entry(p, &mtd_partitions, list)
+			if (p->master == master) {
+				if ((start >= p->offset) &&
+				    (start < (p->offset + p->mtd.size)))
+					goto err_inv;
+
+				if ((end >= p->offset) &&
+				    (end < (p->offset + p->mtd.size)))
+					goto err_inv;
+			}
+	}
+ 
+ 	list_add(&new->list, &mtd_partitions);
+ 	mutex_unlock(&mtd_partitions_mutex);
+ 
+ 	add_mtd_device(&new->mtd);
+	mtd_partition_split(master, new);
+ 
+ 	return ret;
+ err_inv:
+@@ -590,6 +599,12 @@ err_inv:
+ }
+ EXPORT_SYMBOL_GPL(mtd_add_partition);
+ 
+int mtd_add_partition(struct mtd_info *master, char *name,
+		      long long offset, long long length)
+{
+	return __mtd_add_partition(master, name, offset, length, true);
+}
+
+ int mtd_del_partition(struct mtd_info *master, int partno)
+ {
+ 	struct mtd_part *slave, *next;
+@@ -613,6 +628,149 @@ int mtd_del_partition(struct mtd_info *m
 }
 EXPORT_SYMBOL_GPL(mtd_del_partition);
 
+static inline unsigned long
+mtd_pad_erasesize(struct mtd_info *mtd, int offset, int len)
+{
+	unsigned long mask = mtd->erasesize - 1;
+
+	len += offset & mask;
+	len = (len + mask) & ~mask;
+	len -= offset & mask;
+	return len;
+}
+
 +#ifdef CONFIG_MTD_ROOTFS_SPLIT
 +#define ROOTFS_SPLIT_NAME "rootfs_data"
 +#define ROOTFS_REMOVED_NAME "<removed>"
@ -77,105 +165,118 @@
 +	}
 +
 +	len = (u32) le64_to_cpu(sb.bytes_used);
-+	len += (offset & 0x000fffff);
-+	len +=  (master->erasesize - 1);
-+	len &= ~(master->erasesize - 1);
-+	len -= (offset & 0x000fffff);
+	len = mtd_pad_erasesize(master, offset, len);
 +	*split_offset = offset + len;
 +
 +	return 0;
 +}
 +
-+static int split_rootfs_data(struct mtd_info *master, struct mtd_info *rpart, const struct mtd_partition *part)
+static void split_rootfs_data(struct mtd_info *master, struct mtd_part *part)
 +{
-+	struct mtd_partition dpart;
-+	struct mtd_part *slave = NULL;
-+	struct mtd_part *spart;
-+	int ret, split_offset = 0;
+	unsigned int split_offset = 0;
+	unsigned int split_size;
+	int ret;
 +
-+	spart = PART(rpart);
-+	ret = split_squashfs(master, spart->offset, &split_offset);
+	ret = split_squashfs(master, part->offset, &split_offset);
 +	if (ret)
-+		return ret;
+		return;
 +
 +	if (split_offset <= 0)
-+		return 0;
+		return;
 +
-+	memcpy(&dpart, part, sizeof(dpart));
-+	dpart.name = ROOTFS_SPLIT_NAME;
+	split_size = part->mtd.size - (split_offset - part->offset);
+	printk(KERN_INFO "mtd: partition \"%s\" created automatically, ofs=0x%x, len=0x%x\n",
+		ROOTFS_SPLIT_NAME, split_offset, split_size);
 +
-+	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;
+	__mtd_add_partition(master, ROOTFS_SPLIT_NAME, split_offset,
+			    split_size, false);
 +}
 +#endif /* CONFIG_MTD_ROOTFS_SPLIT */
 +
+#ifdef CONFIG_MTD_UIMAGE_SPLIT
+#define UBOOT_MAGIC	0x27051956
+
+static void split_uimage(struct mtd_info *master, struct mtd_part *part)
+{
+	struct {
+		__be32 magic;
+		__be32 pad[2];
+		__be32 size;
+	} hdr;
+	size_t len;
+
+	if (strcmp(part->mtd.name, CONFIG_MTD_UIMAGE_SPLIT_NAME) != 0)
+		return;
+
+	if (mtd_read(master, part->offset, sizeof(hdr), &len, (void *) &hdr))
+		return;
+
+	if (len != sizeof(hdr) || hdr.magic != cpu_to_be32(UBOOT_MAGIC))
+		return;
+
+	len = be32_to_cpu(hdr.size) + 0x40;
+	len = mtd_pad_erasesize(master, part->offset, len);
+	if (len + master->erasesize > part->mtd.size)
+		return;
+
+	__mtd_add_partition(master, "rootfs", part->offset + len,
+			    part->mtd.size - len, false);
+}
+#endif
+
+void __weak arch_split_mtd_part(struct mtd_info *master, const char *name,
+                                int offset, int size)
+{
+}
+
+
+static void mtd_partition_split(struct mtd_info *master, struct mtd_part *part)
+{
+	static int rootfs_found = 0;
+
+	if (rootfs_found)
+		return;
+
+	if (!strcmp(part->mtd.name, "rootfs")) {
+		rootfs_found = 1;
+
+#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, part->mtd.index);
+		}
+#endif
+#ifdef CONFIG_MTD_ROOTFS_SPLIT
+		split_rootfs_data(master, part);
+#endif
+	}
+
+#ifdef CONFIG_MTD_UIMAGE_SPLIT
+	split_uimage(master, part);
+#endif
+
+	arch_split_mtd_part(master, part->mtd.name, part->offset,
+			    part->mtd.size);
+}
 /*
  * 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 *
+@@ -642,6 +800,7 @@ int add_mtd_partitions(struct mtd_info *
+ 		mutex_unlock(&mtd_partitions_mutex);
 
 		add_mtd_device(&slave->mtd);
+		mtd_partition_split(master, slave);
 
-+		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/partitions.h
+++ b/include/linux/mtd/partitions.h
+@@ -84,5 +84,7 @@ int mtd_add_partition(struct mtd_info *m
+ 		      long long offset, long long length);
+ int mtd_del_partition(struct mtd_info *master, int partno);
+ uint64_t mtd_get_device_size(const struct mtd_info *mtd);
+extern void __weak arch_split_mtd_part(struct mtd_info *master,
+				       const char *name, int offset, int 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.
+ #endif