kernel/3.10: add more helpers to the mtdsplit code

Signed-off-by: Gabor Juhos <juhosg@openwrt.org>
SVN-Revision: 38111

diff --git a/target/linux/generic/files/drivers/mtd/mtdsplit.c b/target/linux/generic/files/drivers/mtd/mtdsplit.c
index 0ba35fe950b5ccb10b6224950184fb9729e55573..162739f472e929378f7a5e72cc441787e8668211 100644 (file)
--- a/target/linux/generic/files/drivers/mtd/mtdsplit.c
+++ b/target/linux/generic/files/drivers/mtd/mtdsplit.c
@@ -64,3 +64,53 @@ int mtd_get_squashfs_len(struct mtd_info *master,
        return 0;
 }
 EXPORT_SYMBOL_GPL(mtd_get_squashfs_len);
+
+static ssize_t mtd_next_eb(struct mtd_info *mtd, size_t offset)
+{
+       return mtd_rounddown_to_eb(offset, mtd) + mtd->erasesize;
+}
+
+int mtd_check_rootfs_magic(struct mtd_info *mtd, size_t offset)
+{
+       u32 magic;
+       size_t retlen;
+       int ret;
+
+       ret = mtd_read(mtd, offset, sizeof(magic), &retlen,
+                      (unsigned char *) &magic);
+       if (ret)
+               return ret;
+
+       if (retlen != sizeof(magic))
+               return -EIO;
+
+       if (le32_to_cpu(magic) != SQUASHFS_MAGIC &&
+           magic != 0x19852003)
+               return -EINVAL;
+
+       return 0;
+}
+EXPORT_SYMBOL_GPL(mtd_check_rootfs_magic);
+
+int mtd_find_rootfs_from(struct mtd_info *mtd,
+                        size_t from,
+                        size_t limit,
+                        size_t *ret_offset)
+{
+       size_t offset;
+       int err;
+
+       for (offset = from; offset < limit;
+            offset = mtd_next_eb(mtd, offset)) {
+               err = mtd_check_rootfs_magic(mtd, offset);
+               if (err)
+                       continue;
+
+               *ret_offset = offset;
+               return 0;
+       }
+
+       return -ENODEV;
+}
+EXPORT_SYMBOL_GPL(mtd_find_rootfs_from);
+

diff --git a/target/linux/generic/files/drivers/mtd/mtdsplit.h b/target/linux/generic/files/drivers/mtd/mtdsplit.h
index 8ba6c8b2003c8ec210831d6e78ad1ac9b591371f..48cb44c090db1eda2574b88fc013213364c36bbf 100644 (file)
--- a/target/linux/generic/files/drivers/mtd/mtdsplit.h
+++ b/target/linux/generic/files/drivers/mtd/mtdsplit.h
@@ -19,6 +19,14 @@
 int mtd_get_squashfs_len(struct mtd_info *master,
                         size_t offset,
                         size_t *squashfs_len);
+
+int mtd_check_rootfs_magic(struct mtd_info *mtd, size_t offset);
+
+int mtd_find_rootfs_from(struct mtd_info *mtd,
+                        size_t from,
+                        size_t limit,
+                        size_t *ret_offset);
+
 #else
 static inline int mtd_get_squashfs_len(struct mtd_info *master,
                                       size_t offset,
@@ -26,6 +34,19 @@ static inline int mtd_get_squashfs_len(struct mtd_info *master,
 {
        return -ENODEV;
 }
-#endif
+
+static inline int mtd_check_rootfs_magic(struct mtd_info *mtd, size_t offset)
+{
+       return -EINVAL;
+}
+
+static inline int mtd_find_rootfs_from(struct mtd_info *mtd,
+                                      size_t from,
+                                      size_t limit,
+                                      size_t *ret_offset)
+{
+       return -ENODEV;
+}
+#endif /* CONFIG_MTD_SPLIT */
 
 #endif /* _MTDSPLIT_H */