[PATCH 6/9] drivers:mtd:ubi:add hook for UBI bakvol in ubi_io_write

[Bean Huo 霍斌斌 (beanhuo)]

Add hook for UBI bakvol in ubi_io_write.

Modify ubi_io_write, if program lower page of MLC NAND,
Duplicated it and backup one copy into internal log volume by
Dual plane program method.

Signed-off-by: Bean Huo <beanhuo at micron.com>
---
 drivers/mtd/ubi/io.c | 63 +++++++++++++++++++++++++++++++++++++++++++++-------
 1 file changed, 55 insertions(+), 8 deletions(-)

diff --git a/drivers/mtd/ubi/io.c b/drivers/mtd/ubi/io.c
index 5bbd1f0..912c458 100644
--- a/drivers/mtd/ubi/io.c
+++ b/drivers/mtd/ubi/io.c
@@ -236,8 +236,9 @@ int ubi_io_write(struct ubi_device *ubi, const void *buf, int pnum, int offset,
 		 int len)
 {
 	int err;
-	size_t written;
+	size_t retlen;
 	loff_t addr;
+	int skip = 0;
 
 	dbg_io("write %d bytes to PEB %d:%d", len, pnum, offset);
 
@@ -281,14 +282,60 @@ int ubi_io_write(struct ubi_device *ubi, const void *buf, int pnum, int offset,
 	}
 
 	addr = (loff_t)pnum * ubi->peb_size + offset;
-	err = mtd_write(ubi->mtd, addr, len, &written, buf);
-	if (err) {
-		ubi_err(ubi, "error %d while writing %d bytes to PEB %d:%d, written %zd bytes",
-			err, len, pnum, offset, written);
-		dump_stack();
-		ubi_dump_flash(ubi, pnum, offset, len);
+
+#ifdef CONFIG_MTD_UBI_MLC_NAND_BAKVOL
+	if ((offset == 0) && (len == ubi->peb_size))
+		skip = 1;
+
+	if (ubi_check_backup_volume(ubi) && (!skip)) {
+		loff_t addr_temp;
+		unsigned char *buf_temp = (unsigned char *)buf;
+		int len_temp;
+		int writelen = 0;
+
+		addr_temp = addr;
+
+		for (len_temp = len; len_temp > 0; len_temp -= ubi->min_io_size,
+			addr_temp += ubi->min_io_size,
+			buf_temp += ubi->min_io_size) {
+			/* Split data according to min_io_size */
+
+			if (len_temp/ubi->min_io_size)
+				writelen = ubi->min_io_size;
+			else
+				writelen %= ubi->min_io_size;
+
+			if (is_backup_need(ubi, addr_temp)) {
+				err = ubi_backup_data_to_backup_volume(ubi,
+					addr_temp, writelen, &retlen, buf_temp);
+				} else
+				err = mtd_write(ubi->mtd, addr_temp, writelen,
+						&retlen, buf_temp);
+
+			if (err) {
+				ubi_err(ubi, "Writing %d byptes to PEB %d:%d",
+					writelen, pnum, offset);
+				ubi_err(ubi, "Error %d", err);
+				ubi_err(ubi, "Written %zd bytes", retlen);
+				dump_stack();
+				ubi_dump_flash(ubi, pnum, offset, writelen);
+				} else
+				ubi_assert(retlen == writelen);
+		}
 	} else
-		ubi_assert(written == len);
+#endif
+	{
+		err = mtd_write(ubi->mtd, addr, len, &retlen, buf);
+		if (err) {
+			ubi_err(ubi, "Writing %d byptes to PEB %d:%d",
+				len, pnum, offset);
+			ubi_err(ubi, "Error %d", err);
+			ubi_err(ubi, "Written %zd bytes", retlen);
+			dump_stack();
+			ubi_dump_flash(ubi, pnum, offset, len);
+		} else
+			ubi_assert(retlen == len);
+	}
 
 	if (!err) {
 		err = self_check_write(ubi, buf, pnum, offset, len);
-- 
1.9.1