openwrtv4/target/linux/generic/pending-4.9/431-mtd-bcm47xxpart-check-for-bad-blocks-when-calculatin.patch

From: =?UTF-8?q?Rafa=C5=82=20Mi=C5=82ecki?= <zajec5@gmail.com>
Subject: [PATCH] mtd: bcm47xxpart: check for bad blocks when calculating offsets

Signed-off-by: Rafał Miłecki <zajec5@gmail.com>
---

--- a/drivers/mtd/parsers/parser_trx.c
+++ b/drivers/mtd/parsers/parser_trx.c
@@ -29,6 +29,33 @@ struct trx_header {
 	uint32_t offset[3];
 } __packed;
 
+/*
+ * Calculate real end offset (address) for a given amount of data. It checks
+ * all blocks skipping bad ones.
+ */
+static size_t parser_trx_real_offset(struct mtd_info *mtd, size_t bytes)
+{
+	size_t real_offset = 0;
+
+	if (mtd_block_isbad(mtd, real_offset))
+		pr_warn("Base offset shouldn't be at bad block");
+
+	while (bytes >= mtd->erasesize) {
+		bytes -= mtd->erasesize;
+		real_offset += mtd->erasesize;
+		while (mtd_block_isbad(mtd, real_offset)) {
+			real_offset += mtd->erasesize;
+
+			if (real_offset >= mtd->size)
+				return real_offset - mtd->erasesize;
+		}
+	}
+
+	real_offset += bytes;
+
+	return real_offset;
+}
+
 static const char *parser_trx_data_part_name(struct mtd_info *master,
 					     size_t offset)
 {
@@ -83,21 +110,21 @@ static int parser_trx_parse(struct mtd_i
 	if (trx.offset[2]) {
 		part = &parts[curr_part++];
 		part->name = "loader";
-		part->offset = trx.offset[i];
+		part->offset = parser_trx_real_offset(mtd, trx.offset[i]);
 		i++;
 	}
 
 	if (trx.offset[i]) {
 		part = &parts[curr_part++];
 		part->name = "linux";
-		part->offset = trx.offset[i];
+		part->offset = parser_trx_real_offset(mtd, trx.offset[i]);
 		i++;
 	}
 
 	if (trx.offset[i]) {
 		part = &parts[curr_part++];
 		part->name = parser_trx_data_part_name(mtd, trx.offset[i]);
-		part->offset = trx.offset[i];
+		part->offset = parser_trx_real_offset(mtd, trx.offset[i]);
 		i++;
 	}