openwrt/target/linux/generic/patches-3.18/404-mtd-add-more-helper-functions.patch

--- a/drivers/mtd/mtdpart.c
+++ b/drivers/mtd/mtdpart.c
@@ -446,14 +446,12 @@ static struct mtd_part *allocate_partiti
 	if (slave->offset == MTDPART_OFS_APPEND)
 		slave->offset = cur_offset;
 	if (slave->offset == MTDPART_OFS_NXTBLK) {
-		slave->offset = cur_offset;
-		if (mtd_mod_by_eb(cur_offset, master) != 0) {
-			/* Round up to next erasesize */
-			slave->offset = (mtd_div_by_eb(cur_offset, master) + 1) * master->erasesize;
+		/* Round up to next erasesize */
+		slave->offset = mtd_roundup_to_eb(cur_offset, master);
+		if (slave->offset != cur_offset)
 			printk(KERN_NOTICE "Moving partition %d: "
 			       "0x%012llx -> 0x%012llx\n", partno,
 			       (unsigned long long)cur_offset, (unsigned long long)slave->offset);
-		}
 	}
 	if (slave->offset == MTDPART_OFS_RETAIN) {
 		slave->offset = cur_offset;
@@ -673,6 +671,17 @@ run_parsers_by_type(struct mtd_part *sla
 	return nr_parts;
 }
 
+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_SPLIT_FIRMWARE_NAME
 #define SPLIT_FIRMWARE_NAME	CONFIG_MTD_SPLIT_FIRMWARE_NAME
 #else
@@ -956,6 +965,24 @@ int mtd_is_partition(const struct mtd_in
 }
 EXPORT_SYMBOL_GPL(mtd_is_partition);
 
+struct mtd_info *mtdpart_get_master(const struct mtd_info *mtd)
+{
+	if (!mtd_is_partition(mtd))
+		return (struct mtd_info *)mtd;
+
+	return PART(mtd)->master;
+}
+EXPORT_SYMBOL_GPL(mtdpart_get_master);
+
+uint64_t mtdpart_get_offset(const struct mtd_info *mtd)
+{
+	if (!mtd_is_partition(mtd))
+		return 0;
+
+	return PART(mtd)->offset;
+}
+EXPORT_SYMBOL_GPL(mtdpart_get_offset);
+
 /* Returns the size of the entire flash chip */
 uint64_t mtd_get_device_size(const struct mtd_info *mtd)
 {
--- a/include/linux/mtd/partitions.h
+++ b/include/linux/mtd/partitions.h
@@ -90,6 +90,8 @@ int mtd_is_partition(const struct mtd_in
 int mtd_add_partition(struct mtd_info *master, const char *name,
 		      long long offset, long long length);
 int mtd_del_partition(struct mtd_info *master, int partno);
+struct mtd_info *mtdpart_get_master(const struct mtd_info *mtd);
+uint64_t mtdpart_get_offset(const struct mtd_info *mtd);
 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
@@ -333,6 +333,24 @@ static inline uint32_t mtd_mod_by_eb(uin
 	return do_div(sz, mtd->erasesize);
 }
 
+static inline uint64_t mtd_roundup_to_eb(uint64_t sz, struct mtd_info *mtd)
+{
+	if (mtd_mod_by_eb(sz, mtd) == 0)
+		return sz;
+
+	/* Round up to next erase block */
+	return (mtd_div_by_eb(sz, mtd) + 1) * mtd->erasesize;
+}
+
+static inline uint64_t mtd_rounddown_to_eb(uint64_t sz, struct mtd_info *mtd)
+{
+	if (mtd_mod_by_eb(sz, mtd) == 0)
+		return sz;
+
+	/* Round down to the start of the current erase block */
+	return (mtd_div_by_eb(sz, mtd)) * mtd->erasesize;
+}
+
 static inline uint32_t mtd_div_by_ws(uint64_t sz, struct mtd_info *mtd)
 {
 	if (mtd->writesize_shift)