UBIFS: Implement read-only UBIFS support in U-Boot

The U-Boot UBIFS implementation is largely a direct copy from the current
Linux version (2.6.29-rc6). As already done in the UBI version we have an
"abstraction layer" to redefine or remove some OS calls (e.g. mutex_lock()
...). This makes it possible to use the original Linux code with very
little changes. And by this we can better update to later Linux versions.

I removed some of the Linux features that are not used in the U-Boot
version (e.g. garbage-collection, write support).

Signed-off-by: Stefan Roese <sr@denx.de>
CC: Artem Bityutskiy <dedekind@infradead.org>
CC: Adrian Hunter <ext-Adrian.Hunter@nokia.com>

2 files changed, 93 insertions, 1 deletions

diff --git a/include/linux/math64.h b/include/linux/math64.h
new file mode 100644
index 0000000000..6d760d75c4
--- /dev/null
+++ b/include/linux/math64.h
@@ -0,0 +1,85 @@
+#ifndef _LINUX_MATH64_H
+#define _LINUX_MATH64_H
+
+#include <linux/types.h>
+
+#if BITS_PER_LONG == 64
+
+/**
+ * div_u64_rem - unsigned 64bit divide with 32bit divisor with remainder
+ *
+ * This is commonly provided by 32bit archs to provide an optimized 64bit
+ * divide.
+ */
+static inline u64 div_u64_rem(u64 dividend, u32 divisor, u32 *remainder)
+{
+	*remainder = dividend % divisor;
+	return dividend / divisor;
+}
+
+/**
+ * div_s64_rem - signed 64bit divide with 32bit divisor with remainder
+ */
+static inline s64 div_s64_rem(s64 dividend, s32 divisor, s32 *remainder)
+{
+	*remainder = dividend % divisor;
+	return dividend / divisor;
+}
+
+/**
+ * div64_u64 - unsigned 64bit divide with 64bit divisor
+ */
+static inline u64 div64_u64(u64 dividend, u64 divisor)
+{
+	return dividend / divisor;
+}
+
+#elif BITS_PER_LONG == 32
+
+#ifndef div_u64_rem
+static inline u64 div_u64_rem(u64 dividend, u32 divisor, u32 *remainder)
+{
+	*remainder = do_div(dividend, divisor);
+	return dividend;
+}
+#endif
+
+#ifndef div_s64_rem
+extern s64 div_s64_rem(s64 dividend, s32 divisor, s32 *remainder);
+#endif
+
+#ifndef div64_u64
+extern u64 div64_u64(u64 dividend, u64 divisor);
+#endif
+
+#endif /* BITS_PER_LONG */
+
+/**
+ * div_u64 - unsigned 64bit divide with 32bit divisor
+ *
+ * This is the most common 64bit divide and should be used if possible,
+ * as many 32bit archs can optimize this variant better than a full 64bit
+ * divide.
+ */
+#ifndef div_u64
+static inline u64 div_u64(u64 dividend, u32 divisor)
+{
+	u32 remainder;
+	return div_u64_rem(dividend, divisor, &remainder);
+}
+#endif
+
+/**
+ * div_s64 - signed 64bit divide with 32bit divisor
+ */
+#ifndef div_s64
+static inline s64 div_s64(s64 dividend, s32 divisor)
+{
+	s32 remainder;
+	return div_s64_rem(dividend, divisor, &remainder);
+}
+#endif
+
+u32 iter_div_u64_rem(u64 dividend, u32 divisor, u64 *remainder);
+
+#endif /* _LINUX_MATH64_H */
diff --git a/include/ubi_uboot.h b/include/ubi_uboot.h
index b4152192a2..74312abf03 100644
--- a/include/ubi_uboot.h
+++ b/include/ubi_uboot.h
@@ -18,7 +18,12 @@
 #include <malloc.h>
 #include <div64.h>
 #include <linux/crc32.h>
+#include <linux/types.h>
+#include <linux/list.h>
+#include <linux/rbtree.h>
+#include <linux/string.h>
 #include <linux/mtd/mtd.h>
+#include <linux/mtd/ubi.h>
 
 #ifdef CONFIG_CMD_ONENAND
 #include <onenand_uboot.h>
@@ -193,7 +198,7 @@ static inline long IS_ERR(const void *ptr)
 
 /* module */
 #define THIS_MODULE		0
-#define try_module_get(...)	0
+#define try_module_get(...)	1
 #define module_put(...)		do { } while (0)
 #define module_init(...)
 #define module_exit(...)
@@ -206,7 +211,9 @@ static inline long IS_ERR(const void *ptr)
 #define MODULE_AUTHOR(...)
 #define MODULE_LICENSE(...)
 
+#ifndef __UBIFS_H__
 #include "../drivers/mtd/ubi/ubi.h"
+#endif
 
 /* functions */
 extern int ubi_mtd_param_parse(const char *val, struct kernel_param *kp);