openwrt/target/linux/generic/backport-4.9/065-v4.13-0005-mtd-partitions-rename-master-to-the-parent-where-app.patch

From 0a9d72b69da6d8dae1abd7990c6c4c749846ef3e Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Rafa=C5=82=20Mi=C5=82ecki?= <rafal@milecki.pl>
Date: Wed, 21 Jun 2017 08:26:44 +0200
Subject: [PATCH] mtd: partitions: rename "master" to the "parent" where
 appropriate
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

This prepares mtd subsystem for the new feature: subpartitions. In some
cases flash device partition can be a container with extra subpartitions
(volumes).

So far there was a flat structure implemented. One master (flash device)
could be partitioned into few partitions. Every partition got its master
and it was enough to get things running.

To support subpartitions we need to store pointer to the parent for each
partition. This is required to implement more natural tree structure and
handle all recursion and offsets calculation.

To make code consistent this patch renamed "master" to the "parent" in
places where we can be dealing with subpartitions.

Signed-off-by: Rafał Miłecki <rafal@milecki.pl>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
---
 drivers/mtd/mtdpart.c | 204 ++++++++++++++++++++++++++------------------------
 1 file changed, 105 insertions(+), 99 deletions(-)

--- a/drivers/mtd/mtdpart.c
+++ b/drivers/mtd/mtdpart.c
@@ -37,10 +37,16 @@
 static LIST_HEAD(mtd_partitions);
 static DEFINE_MUTEX(mtd_partitions_mutex);
 
-/* Our partition node structure */
+/**
+ * struct mtd_part - our partition node structure
+ *
+ * @mtd: struct holding partition details
+ * @parent: parent mtd - flash device or another partition
+ * @offset: partition offset relative to the *flash device*
+ */
 struct mtd_part {
 	struct mtd_info mtd;
-	struct mtd_info *master;
+	struct mtd_info *parent;
 	uint64_t offset;
 	struct list_head list;
 };
@@ -67,15 +73,15 @@ static int part_read(struct mtd_info *mt
 	struct mtd_ecc_stats stats;
 	int res;
 
-	stats = part->master->ecc_stats;
-	res = part->master->_read(part->master, from + part->offset, len,
+	stats = part->parent->ecc_stats;
+	res = part->parent->_read(part->parent, from + part->offset, len,
 				  retlen, buf);
 	if (unlikely(mtd_is_eccerr(res)))
 		mtd->ecc_stats.failed +=
-			part->master->ecc_stats.failed - stats.failed;
+			part->parent->ecc_stats.failed - stats.failed;
 	else
 		mtd->ecc_stats.corrected +=
-			part->master->ecc_stats.corrected - stats.corrected;
+			part->parent->ecc_stats.corrected - stats.corrected;
 	return res;
 }
 
@@ -84,7 +90,7 @@ static int part_point(struct mtd_info *m
 {
 	struct mtd_part *part = mtd_to_part(mtd);
 
-	return part->master->_point(part->master, from + part->offset, len,
+	return part->parent->_point(part->parent, from + part->offset, len,
 				    retlen, virt, phys);
 }
 
@@ -92,7 +98,7 @@ static int part_unpoint(struct mtd_info
 {
 	struct mtd_part *part = mtd_to_part(mtd);
 
-	return part->master->_unpoint(part->master, from + part->offset, len);
+	return part->parent->_unpoint(part->parent, from + part->offset, len);
 }
 
 static unsigned long part_get_unmapped_area(struct mtd_info *mtd,
@@ -103,7 +109,7 @@ static unsigned long part_get_unmapped_a
 	struct mtd_part *part = mtd_to_part(mtd);
 
 	offset += part->offset;
-	return part->master->_get_unmapped_area(part->master, len, offset,
+	return part->parent->_get_unmapped_area(part->parent, len, offset,
 						flags);
 }
 
@@ -132,7 +138,7 @@ static int part_read_oob(struct mtd_info
 			return -EINVAL;
 	}
 
-	res = part->master->_read_oob(part->master, from + part->offset, ops);
+	res = part->parent->_read_oob(part->parent, from + part->offset, ops);
 	if (unlikely(res)) {
 		if (mtd_is_bitflip(res))
 			mtd->ecc_stats.corrected++;
@@ -146,7 +152,7 @@ static int part_read_user_prot_reg(struc
 		size_t len, size_t *retlen, u_char *buf)
 {
 	struct mtd_part *part = mtd_to_part(mtd);
-	return part->master->_read_user_prot_reg(part->master, from, len,
+	return part->parent->_read_user_prot_reg(part->parent, from, len,
 						 retlen, buf);
 }
 
@@ -154,7 +160,7 @@ static int part_get_user_prot_info(struc
 				   size_t *retlen, struct otp_info *buf)
 {
 	struct mtd_part *part = mtd_to_part(mtd);
-	return part->master->_get_user_prot_info(part->master, len, retlen,
+	return part->parent->_get_user_prot_info(part->parent, len, retlen,
 						 buf);
 }
 
@@ -162,7 +168,7 @@ static int part_read_fact_prot_reg(struc
 		size_t len, size_t *retlen, u_char *buf)
 {
 	struct mtd_part *part = mtd_to_part(mtd);
-	return part->master->_read_fact_prot_reg(part->master, from, len,
+	return part->parent->_read_fact_prot_reg(part->parent, from, len,
 						 retlen, buf);
 }
 
@@ -170,7 +176,7 @@ static int part_get_fact_prot_info(struc
 				   size_t *retlen, struct otp_info *buf)
 {
 	struct mtd_part *part = mtd_to_part(mtd);
-	return part->master->_get_fact_prot_info(part->master, len, retlen,
+	return part->parent->_get_fact_prot_info(part->parent, len, retlen,
 						 buf);
 }
 
@@ -178,7 +184,7 @@ static int part_write(struct mtd_info *m
 		size_t *retlen, const u_char *buf)
 {
 	struct mtd_part *part = mtd_to_part(mtd);
-	return part->master->_write(part->master, to + part->offset, len,
+	return part->parent->_write(part->parent, to + part->offset, len,
 				    retlen, buf);
 }
 
@@ -186,7 +192,7 @@ static int part_panic_write(struct mtd_i
 		size_t *retlen, const u_char *buf)
 {
 	struct mtd_part *part = mtd_to_part(mtd);
-	return part->master->_panic_write(part->master, to + part->offset, len,
+	return part->parent->_panic_write(part->parent, to + part->offset, len,
 					  retlen, buf);
 }
 
@@ -199,14 +205,14 @@ static int part_write_oob(struct mtd_inf
 		return -EINVAL;
 	if (ops->datbuf && to + ops->len > mtd->size)
 		return -EINVAL;
-	return part->master->_write_oob(part->master, to + part->offset, ops);
+	return part->parent->_write_oob(part->parent, to + part->offset, ops);
 }
 
 static int part_write_user_prot_reg(struct mtd_info *mtd, loff_t from,
 		size_t len, size_t *retlen, u_char *buf)
 {
 	struct mtd_part *part = mtd_to_part(mtd);
-	return part->master->_write_user_prot_reg(part->master, from, len,
+	return part->parent->_write_user_prot_reg(part->parent, from, len,
 						  retlen, buf);
 }
 
@@ -214,14 +220,14 @@ static int part_lock_user_prot_reg(struc
 		size_t len)
 {
 	struct mtd_part *part = mtd_to_part(mtd);
-	return part->master->_lock_user_prot_reg(part->master, from, len);
+	return part->parent->_lock_user_prot_reg(part->parent, from, len);
 }
 
 static int part_writev(struct mtd_info *mtd, const struct kvec *vecs,
 		unsigned long count, loff_t to, size_t *retlen)
 {
 	struct mtd_part *part = mtd_to_part(mtd);
-	return part->master->_writev(part->master, vecs, count,
+	return part->parent->_writev(part->parent, vecs, count,
 				     to + part->offset, retlen);
 }
 
@@ -231,7 +237,7 @@ static int part_erase(struct mtd_info *m
 	int ret;
 
 	instr->addr += part->offset;
-	ret = part->master->_erase(part->master, instr);
+	ret = part->parent->_erase(part->parent, instr);
 	if (ret) {
 		if (instr->fail_addr != MTD_FAIL_ADDR_UNKNOWN)
 			instr->fail_addr -= part->offset;
@@ -257,51 +263,51 @@ EXPORT_SYMBOL_GPL(mtd_erase_callback);
 static int part_lock(struct mtd_info *mtd, loff_t ofs, uint64_t len)
 {
 	struct mtd_part *part = mtd_to_part(mtd);
-	return part->master->_lock(part->master, ofs + part->offset, len);
+	return part->parent->_lock(part->parent, ofs + part->offset, len);
 }
 
 static int part_unlock(struct mtd_info *mtd, loff_t ofs, uint64_t len)
 {
 	struct mtd_part *part = mtd_to_part(mtd);
-	return part->master->_unlock(part->master, ofs + part->offset, len);
+	return part->parent->_unlock(part->parent, ofs + part->offset, len);
 }
 
 static int part_is_locked(struct mtd_info *mtd, loff_t ofs, uint64_t len)
 {
 	struct mtd_part *part = mtd_to_part(mtd);
-	return part->master->_is_locked(part->master, ofs + part->offset, len);
+	return part->parent->_is_locked(part->parent, ofs + part->offset, len);
 }
 
 static void part_sync(struct mtd_info *mtd)
 {
 	struct mtd_part *part = mtd_to_part(mtd);
-	part->master->_sync(part->master);
+	part->parent->_sync(part->parent);
 }
 
 static int part_suspend(struct mtd_info *mtd)
 {
 	struct mtd_part *part = mtd_to_part(mtd);
-	return part->master->_suspend(part->master);
+	return part->parent->_suspend(part->parent);
 }
 
 static void part_resume(struct mtd_info *mtd)
 {
 	struct mtd_part *part = mtd_to_part(mtd);
-	part->master->_resume(part->master);
+	part->parent->_resume(part->parent);
 }
 
 static int part_block_isreserved(struct mtd_info *mtd, loff_t ofs)
 {
 	struct mtd_part *part = mtd_to_part(mtd);
 	ofs += part->offset;
-	return part->master->_block_isreserved(part->master, ofs);
+	return part->parent->_block_isreserved(part->parent, ofs);
 }
 
 static int part_block_isbad(struct mtd_info *mtd, loff_t ofs)
 {
 	struct mtd_part *part = mtd_to_part(mtd);
 	ofs += part->offset;
-	return part->master->_block_isbad(part->master, ofs);
+	return part->parent->_block_isbad(part->parent, ofs);
 }
 
 static int part_block_markbad(struct mtd_info *mtd, loff_t ofs)
@@ -310,7 +316,7 @@ static int part_block_markbad(struct mtd
 	int res;
 
 	ofs += part->offset;
-	res = part->master->_block_markbad(part->master, ofs);
+	res = part->parent->_block_markbad(part->parent, ofs);
 	if (!res)
 		mtd->ecc_stats.badblocks++;
 	return res;
@@ -319,13 +325,13 @@ static int part_block_markbad(struct mtd
 static int part_get_device(struct mtd_info *mtd)
 {
 	struct mtd_part *part = mtd_to_part(mtd);
-	return part->master->_get_device(part->master);
+	return part->parent->_get_device(part->parent);
 }
 
 static void part_put_device(struct mtd_info *mtd)
 {
 	struct mtd_part *part = mtd_to_part(mtd);
-	part->master->_put_device(part->master);
+	part->parent->_put_device(part->parent);
 }
 
 static int part_ooblayout_ecc(struct mtd_info *mtd, int section,
@@ -333,7 +339,7 @@ static int part_ooblayout_ecc(struct mtd
 {
 	struct mtd_part *part = mtd_to_part(mtd);
 
-	return mtd_ooblayout_ecc(part->master, section, oobregion);
+	return mtd_ooblayout_ecc(part->parent, section, oobregion);
 }
 
 static int part_ooblayout_free(struct mtd_info *mtd, int section,
@@ -341,7 +347,7 @@ static int part_ooblayout_free(struct mt
 {
 	struct mtd_part *part = mtd_to_part(mtd);
 
-	return mtd_ooblayout_free(part->master, section, oobregion);
+	return mtd_ooblayout_free(part->parent, section, oobregion);
 }
 
 static const struct mtd_ooblayout_ops part_ooblayout_ops = {
@@ -353,7 +359,7 @@ static int part_max_bad_blocks(struct mt
 {
 	struct mtd_part *part = mtd_to_part(mtd);
 
-	return part->master->_max_bad_blocks(part->master,
+	return part->parent->_max_bad_blocks(part->parent,
 					     ofs + part->offset, len);
 }
 
@@ -363,12 +369,12 @@ static inline void free_partition(struct
 	kfree(p);
 }
 
-static struct mtd_part *allocate_partition(struct mtd_info *master,
+static struct mtd_part *allocate_partition(struct mtd_info *parent,
 			const struct mtd_partition *part, int partno,
 			uint64_t cur_offset)
 {
-	int wr_alignment = (master->flags & MTD_NO_ERASE) ? master->writesize:
-							    master->erasesize;
+	int wr_alignment = (parent->flags & MTD_NO_ERASE) ? parent->writesize:
+							    parent->erasesize;
 	struct mtd_part *slave;
 	u32 remainder;
 	char *name;
@@ -379,25 +385,25 @@ static struct mtd_part *allocate_partiti
 	name = kstrdup(part->name, GFP_KERNEL);
 	if (!name || !slave) {
 		printk(KERN_ERR"memory allocation error while creating partitions for \"%s\"\n",
-		       master->name);
+		       parent->name);
 		kfree(name);
 		kfree(slave);
 		return ERR_PTR(-ENOMEM);
 	}
 
 	/* set up the MTD object for this partition */
-	slave->mtd.type = master->type;
-	slave->mtd.flags = master->flags & ~part->mask_flags;
+	slave->mtd.type = parent->type;
+	slave->mtd.flags = parent->flags & ~part->mask_flags;
 	slave->mtd.size = part->size;
-	slave->mtd.writesize = master->writesize;
-	slave->mtd.writebufsize = master->writebufsize;
-	slave->mtd.oobsize = master->oobsize;
-	slave->mtd.oobavail = master->oobavail;
-	slave->mtd.subpage_sft = master->subpage_sft;
-	slave->mtd.pairing = master->pairing;
+	slave->mtd.writesize = parent->writesize;
+	slave->mtd.writebufsize = parent->writebufsize;
+	slave->mtd.oobsize = parent->oobsize;
+	slave->mtd.oobavail = parent->oobavail;
+	slave->mtd.subpage_sft = parent->subpage_sft;
+	slave->mtd.pairing = parent->pairing;
 
 	slave->mtd.name = name;
-	slave->mtd.owner = master->owner;
+	slave->mtd.owner = parent->owner;
 
 	/* NOTE: Historically, we didn't arrange MTDs as a tree out of
 	 * concern for showing the same data in multiple partitions.
@@ -408,70 +414,70 @@ static struct mtd_part *allocate_partiti
 	 * distinguish between the master and the partition in sysfs.
 	 */
 	slave->mtd.dev.parent = IS_ENABLED(CONFIG_MTD_PARTITIONED_MASTER) ?
-				&master->dev :
-				master->dev.parent;
+				&parent->dev :
+				parent->dev.parent;
 	slave->mtd.dev.of_node = part->of_node;
 
 	slave->mtd._read = part_read;
 	slave->mtd._write = part_write;
 
-	if (master->_panic_write)
+	if (parent->_panic_write)
 		slave->mtd._panic_write = part_panic_write;
 
-	if (master->_point && master->_unpoint) {
+	if (parent->_point && parent->_unpoint) {
 		slave->mtd._point = part_point;
 		slave->mtd._unpoint = part_unpoint;
 	}
 
-	if (master->_get_unmapped_area)
+	if (parent->_get_unmapped_area)
 		slave->mtd._get_unmapped_area = part_get_unmapped_area;
-	if (master->_read_oob)
+	if (parent->_read_oob)
 		slave->mtd._read_oob = part_read_oob;
-	if (master->_write_oob)
+	if (parent->_write_oob)
 		slave->mtd._write_oob = part_write_oob;
-	if (master->_read_user_prot_reg)
+	if (parent->_read_user_prot_reg)
 		slave->mtd._read_user_prot_reg = part_read_user_prot_reg;
-	if (master->_read_fact_prot_reg)
+	if (parent->_read_fact_prot_reg)
 		slave->mtd._read_fact_prot_reg = part_read_fact_prot_reg;
-	if (master->_write_user_prot_reg)
+	if (parent->_write_user_prot_reg)
 		slave->mtd._write_user_prot_reg = part_write_user_prot_reg;
-	if (master->_lock_user_prot_reg)
+	if (parent->_lock_user_prot_reg)
 		slave->mtd._lock_user_prot_reg = part_lock_user_prot_reg;
-	if (master->_get_user_prot_info)
+	if (parent->_get_user_prot_info)
 		slave->mtd._get_user_prot_info = part_get_user_prot_info;
-	if (master->_get_fact_prot_info)
+	if (parent->_get_fact_prot_info)
 		slave->mtd._get_fact_prot_info = part_get_fact_prot_info;
-	if (master->_sync)
+	if (parent->_sync)
 		slave->mtd._sync = part_sync;
-	if (!partno && !master->dev.class && master->_suspend &&
-	    master->_resume) {
+	if (!partno && !parent->dev.class && parent->_suspend &&
+	    parent->_resume) {
 			slave->mtd._suspend = part_suspend;
 			slave->mtd._resume = part_resume;
 	}
-	if (master->_writev)
+	if (parent->_writev)
 		slave->mtd._writev = part_writev;
-	if (master->_lock)
+	if (parent->_lock)
 		slave->mtd._lock = part_lock;
-	if (master->_unlock)
+	if (parent->_unlock)
 		slave->mtd._unlock = part_unlock;
-	if (master->_is_locked)
+	if (parent->_is_locked)
 		slave->mtd._is_locked = part_is_locked;
-	if (master->_block_isreserved)
+	if (parent->_block_isreserved)
 		slave->mtd._block_isreserved = part_block_isreserved;
-	if (master->_block_isbad)
+	if (parent->_block_isbad)
 		slave->mtd._block_isbad = part_block_isbad;
-	if (master->_block_markbad)
+	if (parent->_block_markbad)
 		slave->mtd._block_markbad = part_block_markbad;
-	if (master->_max_bad_blocks)
+	if (parent->_max_bad_blocks)
 		slave->mtd._max_bad_blocks = part_max_bad_blocks;
 
-	if (master->_get_device)
+	if (parent->_get_device)
 		slave->mtd._get_device = part_get_device;
-	if (master->_put_device)
+	if (parent->_put_device)
 		slave->mtd._put_device = part_put_device;
 
 	slave->mtd._erase = part_erase;
-	slave->master = master;
+	slave->parent = parent;
 	slave->offset = part->offset;
 
 	if (slave->offset == MTDPART_OFS_APPEND)
@@ -489,25 +495,25 @@ static struct mtd_part *allocate_partiti
 	}
 	if (slave->offset == MTDPART_OFS_RETAIN) {
 		slave->offset = cur_offset;
-		if (master->size - slave->offset >= slave->mtd.size) {
-			slave->mtd.size = master->size - slave->offset
+		if (parent->size - slave->offset >= slave->mtd.size) {
+			slave->mtd.size = parent->size - slave->offset
 							- slave->mtd.size;
 		} else {
 			printk(KERN_ERR "mtd partition \"%s\" doesn't have enough space: %#llx < %#llx, disabled\n",
-				part->name, master->size - slave->offset,
+				part->name, parent->size - slave->offset,
 				slave->mtd.size);
 			/* register to preserve ordering */
 			goto out_register;
 		}
 	}
 	if (slave->mtd.size == MTDPART_SIZ_FULL)
-		slave->mtd.size = master->size - slave->offset;
+		slave->mtd.size = parent->size - slave->offset;
 
 	printk(KERN_NOTICE "0x%012llx-0x%012llx : \"%s\"\n", (unsigned long long)slave->offset,
 		(unsigned long long)(slave->offset + slave->mtd.size), slave->mtd.name);
 
 	/* let's do some sanity checks */
-	if (slave->offset >= master->size) {
+	if (slave->offset >= parent->size) {
 		/* let's register it anyway to preserve ordering */
 		slave->offset = 0;
 		slave->mtd.size = 0;
@@ -515,16 +521,16 @@ static struct mtd_part *allocate_partiti
 			part->name);
 		goto out_register;
 	}
-	if (slave->offset + slave->mtd.size > master->size) {
-		slave->mtd.size = master->size - slave->offset;
+	if (slave->offset + slave->mtd.size > parent->size) {
+		slave->mtd.size = parent->size - slave->offset;
 		printk(KERN_WARNING"mtd: partition \"%s\" extends beyond the end of device \"%s\" -- size truncated to %#llx\n",
-			part->name, master->name, (unsigned long long)slave->mtd.size);
+			part->name, parent->name, (unsigned long long)slave->mtd.size);
 	}
-	if (master->numeraseregions > 1) {
+	if (parent->numeraseregions > 1) {
 		/* Deal with variable erase size stuff */
-		int i, max = master->numeraseregions;
+		int i, max = parent->numeraseregions;
 		u64 end = slave->offset + slave->mtd.size;
-		struct mtd_erase_region_info *regions = master->eraseregions;
+		struct mtd_erase_region_info *regions = parent->eraseregions;
 
 		/* Find the first erase regions which is part of this
 		 * partition. */
@@ -543,7 +549,7 @@ static struct mtd_part *allocate_partiti
 		BUG_ON(slave->mtd.erasesize == 0);
 	} else {
 		/* Single erase size */
-		slave->mtd.erasesize = master->erasesize;
+		slave->mtd.erasesize = parent->erasesize;
 	}
 
 	tmp = slave->offset;
@@ -566,17 +572,17 @@ static struct mtd_part *allocate_partiti
 	}
 
 	mtd_set_ooblayout(&slave->mtd, &part_ooblayout_ops);
-	slave->mtd.ecc_step_size = master->ecc_step_size;
-	slave->mtd.ecc_strength = master->ecc_strength;
-	slave->mtd.bitflip_threshold = master->bitflip_threshold;
+	slave->mtd.ecc_step_size = parent->ecc_step_size;
+	slave->mtd.ecc_strength = parent->ecc_strength;
+	slave->mtd.bitflip_threshold = parent->bitflip_threshold;
 
-	if (master->_block_isbad) {
+	if (parent->_block_isbad) {
 		uint64_t offs = 0;
 
 		while (offs < slave->mtd.size) {
-			if (mtd_block_isreserved(master, offs + slave->offset))
+			if (mtd_block_isreserved(parent, offs + slave->offset))
 				slave->mtd.ecc_stats.bbtblocks++;
-			else if (mtd_block_isbad(master, offs + slave->offset))
+			else if (mtd_block_isbad(parent, offs + slave->offset))
 				slave->mtd.ecc_stats.badblocks++;
 			offs += slave->mtd.erasesize;
 		}
@@ -610,7 +616,7 @@ static int mtd_add_partition_attrs(struc
 	return ret;
 }
 
-int mtd_add_partition(struct mtd_info *master, const char *name,
+int mtd_add_partition(struct mtd_info *parent, const char *name,
 		      long long offset, long long length)
 {
 	struct mtd_partition part;
@@ -623,7 +629,7 @@ int mtd_add_partition(struct mtd_info *m
 		return -EINVAL;
 
 	if (length == MTDPART_SIZ_FULL)
-		length = master->size - offset;
+		length = parent->size - offset;
 
 	if (length <= 0)
 		return -EINVAL;
@@ -633,7 +639,7 @@ int mtd_add_partition(struct mtd_info *m
 	part.size = length;
 	part.offset = offset;
 
-	new = allocate_partition(master, &part, -1, offset);
+	new = allocate_partition(parent, &part, -1, offset);
 	if (IS_ERR(new))
 		return PTR_ERR(new);
 
@@ -683,7 +689,7 @@ int del_mtd_partitions(struct mtd_info *
 
 	mutex_lock(&mtd_partitions_mutex);
 	list_for_each_entry_safe(slave, next, &mtd_partitions, list)
-		if (slave->master == master) {
+		if (slave->parent == master) {
 			ret = __mtd_del_partition(slave);
 			if (ret < 0)
 				err = ret;
@@ -700,7 +706,7 @@ int mtd_del_partition(struct mtd_info *m
 
 	mutex_lock(&mtd_partitions_mutex);
 	list_for_each_entry_safe(slave, next, &mtd_partitions, list)
-		if ((slave->master == master) &&
+		if ((slave->parent == master) &&
 		    (slave->mtd.index == partno)) {
 			ret = __mtd_del_partition(slave);
 			break;
@@ -933,6 +939,6 @@ uint64_t mtd_get_device_size(const struc
 	if (!mtd_is_partition(mtd))
 		return mtd->size;
 
-	return mtd_to_part(mtd)->master->size;
+	return mtd_to_part(mtd)->parent->size;
 }
 EXPORT_SYMBOL_GPL(mtd_get_device_size);