kernel: backport upstream ubifs default compression selection fix

Signed-off-by: Rafał Miłecki <rafal@milecki.pl>

1 files changed, 46 insertions, 0 deletions

diff --git a/target/linux/generic/backport-4.19/500-v4.20-ubifs-Fix-default-compression-selection-in-ubifs.patch b/target/linux/generic/backport-4.19/500-v4.20-ubifs-Fix-default-compression-selection-in-ubifs.patch
new file mode 100644
index 0000000000..7bd3ed9fad
--- /dev/null
+++ b/target/linux/generic/backport-4.19/500-v4.20-ubifs-Fix-default-compression-selection-in-ubifs.patch
@@ -0,0 +1,46 @@
+From d62e98ed1efcaa94caa004f622944afdce5f1c3c Mon Sep 17 00:00:00 2001
+From: Gabor Juhos <juhosg@openwrt.org>
+Date: Sun, 9 Dec 2018 18:12:13 +0100
+Subject: [PATCH] ubifs: Fix default compression selection in ubifs
+
+When ubifs is build without the LZO compressor and no compressor is
+given the creation of the default file system will fail. before
+selection the LZO compressor check if it is present and if not fall back
+to the zlib or none.
+
+Signed-off-by: Gabor Juhos <juhosg@openwrt.org>
+Signed-off-by: Hauke Mehrtens <hauke@hauke-m.de>
+Signed-off-by: Richard Weinberger <richard@nod.at>
+---
+ fs/ubifs/sb.c | 13 ++++++++++++-
+ 1 file changed, 12 insertions(+), 1 deletion(-)
+
+--- a/fs/ubifs/sb.c
++++ b/fs/ubifs/sb.c
+@@ -63,6 +63,17 @@
+ /* Default time granularity in nanoseconds */
+ #define DEFAULT_TIME_GRAN 1000000000
+ 
++static int get_default_compressor(struct ubifs_info *c)
++{
++	if (ubifs_compr_present(c, UBIFS_COMPR_LZO))
++		return UBIFS_COMPR_LZO;
++
++	if (ubifs_compr_present(c, UBIFS_COMPR_ZLIB))
++		return UBIFS_COMPR_ZLIB;
++
++	return UBIFS_COMPR_NONE;
++}
++
+ /**
+  * create_default_filesystem - format empty UBI volume.
+  * @c: UBIFS file-system description object
+@@ -186,7 +197,7 @@ static int create_default_filesystem(str
+ 	if (c->mount_opts.override_compr)
+ 		sup->default_compr = cpu_to_le16(c->mount_opts.compr_type);
+ 	else
+-		sup->default_compr = cpu_to_le16(UBIFS_COMPR_LZO);
++		sup->default_compr = cpu_to_le16(get_default_compressor(c));
+ 
+ 	generate_random_uuid(sup->uuid);
+