openwrt/target/linux/generic/patches-3.14/490-mtd-ubi-add-EOF-marker-support.patch
John Crispin 5d2c810101 kernel: add the ubifs EOF marker support to 3.14 kernel
Without this patch the UBIFS driver is unable to attach to the mtd
storage and mount the root FS.

Fixes a kernel panic with Netgear WNDR4300/3700v4 devices.

Signed-off-by: Gianluca Anzolin <gianluca@sottospazio.it>

SVN-Revision: 43287
2014-11-17 08:34:03 +00:00

52 lines
1.1 KiB
Diff

--- a/drivers/mtd/ubi/attach.c
+++ b/drivers/mtd/ubi/attach.c
@@ -800,6 +800,13 @@ out_unlock:
return err;
}
+static bool ec_hdr_has_eof(struct ubi_ec_hdr *ech)
+{
+ return ech->padding1[0] == 'E' &&
+ ech->padding1[1] == 'O' &&
+ ech->padding1[2] == 'F';
+}
+
/**
* scan_peb - scan and process UBI headers of a PEB.
* @ubi: UBI device description object
@@ -830,9 +837,21 @@ static int scan_peb(struct ubi_device *u
return 0;
}
- err = ubi_io_read_ec_hdr(ubi, pnum, ech, 0);
- if (err < 0)
- return err;
+ if (!ai->eof_found) {
+ err = ubi_io_read_ec_hdr(ubi, pnum, ech, 0);
+ if (err < 0)
+ return err;
+
+ if (ec_hdr_has_eof(ech)) {
+ ubi_msg("EOF marker found, PEBs from %d will be erased",
+ pnum);
+ ai->eof_found = true;
+ }
+ }
+
+ if (ai->eof_found)
+ err = UBI_IO_FF_BITFLIPS;
+
switch (err) {
case 0:
break;
--- a/drivers/mtd/ubi/ubi.h
+++ b/drivers/mtd/ubi/ubi.h
@@ -701,6 +701,7 @@ struct ubi_attach_info {
int mean_ec;
uint64_t ec_sum;
int ec_count;
+ bool eof_found;
struct kmem_cache *aeb_slab_cache;
};