bcm53xx: fix UBI EOF patch to allow sysupgrade after first installation

With previous version of patch info about need of erasing blocks was
stored once per boot. It was breaking in following scenario:
1) First boot after installation (erasing blocks after 0xdeadc0de)
2) Doing sysupgrade (with ubidetach & ubiformat)
3) Attaching UBI again (it caused all blocks to be erased)

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

SVN-Revision: 45387

target/linux/bcm53xx/patches-3.18/500-UBI-Detect-EOF-mark-and-erase-all-remaining-blocks.patch

@@ -1,4 +1,4 @@
-From f41f8b42db092e505382f7120994de21590dff48 Mon Sep 17 00:00:00 2001
+From 2a2af518266a29323cf30c3f9ba9ef2ceb1dd84b Mon Sep 17 00:00:00 2001
 From: =?UTF-8?q?Rafa=C5=82=20Mi=C5=82ecki?= <zajec5@gmail.com>
 Date: Thu, 16 Oct 2014 20:52:16 +0200
 Subject: [PATCH] UBI: Detect EOF mark and erase all remaining blocks
@@ -8,20 +8,39 @@ Content-Transfer-Encoding: 8bit
 
 Signed-off-by: Rafał Miłecki <zajec5@gmail.com>
 ---
- drivers/mtd/ubi/io.c | 5 +++++
- 1 file changed, 5 insertions(+)
+ drivers/mtd/ubi/attach.c | 5 +++++
+ drivers/mtd/ubi/io.c     | 4 ++++
+ drivers/mtd/ubi/ubi.h    | 1 +
+ 3 files changed, 10 insertions(+)
 
+diff --git a/drivers/mtd/ubi/attach.c b/drivers/mtd/ubi/attach.c
+index 380268b..8f525c2 100644
+--- a/drivers/mtd/ubi/attach.c
++++ b/drivers/mtd/ubi/attach.c
+@@ -95,6 +95,9 @@ static int self_check_ai(struct ubi_device *ubi, struct ubi_attach_info *ai);
+ static struct ubi_ec_hdr *ech;
+ static struct ubi_vid_hdr *vidh;
+ 
++/* Set on finding block with 0xdeadc0de, indicates erasing all blocks behind */
++bool erase_all_next;
++
+ /**
+  * add_to_list - add physical eraseblock to a list.
+  * @ai: attaching information
+@@ -1418,6 +1421,8 @@ int ubi_attach(struct ubi_device *ubi, int force_scan)
+ 	if (!ai)
+ 		return -ENOMEM;
+ 
++	erase_all_next = false;
++
+ #ifdef CONFIG_MTD_UBI_FASTMAP
+ 	/* On small flash devices we disable fastmap in any case. */
+ 	if ((int)mtd_div_by_eb(ubi->mtd->size, ubi->mtd) <= UBI_FM_MAX_START) {
+diff --git a/drivers/mtd/ubi/io.c b/drivers/mtd/ubi/io.c
+index d361349..f3d29ce 100644
 --- a/drivers/mtd/ubi/io.c
 +++ b/drivers/mtd/ubi/io.c
-@@ -727,6 +727,7 @@ bad:
-  * o %UBI_IO_FF if only 0xFF bytes were read (the PEB is supposedly empty)
-  * o a negative error code in case of failure.
-  */
-+static bool erase_all_next = false;
- int ubi_io_read_ec_hdr(struct ubi_device *ubi, int pnum,
- 		       struct ubi_ec_hdr *ec_hdr, int verbose)
- {
-@@ -753,6 +754,10 @@ int ubi_io_read_ec_hdr(struct ubi_device
+@@ -753,6 +753,10 @@ int ubi_io_read_ec_hdr(struct ubi_device *ubi, int pnum,
  	}
  
  	magic = be32_to_cpu(ec_hdr->magic);
@@ -32,3 +51,18 @@ Signed-off-by: Rafał Miłecki <zajec5@gmail.com>
  	if (magic != UBI_EC_HDR_MAGIC) {
  		if (mtd_is_eccerr(read_err))
  			return UBI_IO_BAD_HDR_EBADMSG;
+diff --git a/drivers/mtd/ubi/ubi.h b/drivers/mtd/ubi/ubi.h
+index 1259e72..142ee3d 100644
+--- a/drivers/mtd/ubi/ubi.h
++++ b/drivers/mtd/ubi/ubi.h
+@@ -743,6 +743,7 @@ extern struct mutex ubi_devices_mutex;
+ extern struct blocking_notifier_head ubi_notifiers;
+ 
+ /* attach.c */
++extern bool erase_all_next;
+ int ubi_add_to_av(struct ubi_device *ubi, struct ubi_attach_info *ai, int pnum,
+ 		  int ec, const struct ubi_vid_hdr *vid_hdr, int bitflips);
+ struct ubi_ainf_volume *ubi_find_av(const struct ubi_attach_info *ai,
+-- 
+1.8.4.5
+