kernel: copy kernel 4.19 code to 5.4

No changes were done to the patches while coping them. Currently they do
not apply on top of kernel 5.4.

Signed-off-by: Hauke Mehrtens <hauke@hauke-m.de>

1 files changed, 66 insertions, 0 deletions

diff --git a/target/linux/generic/pending-5.4/491-ubi-auto-create-ubiblock-device-for-rootfs.patch b/target/linux/generic/pending-5.4/491-ubi-auto-create-ubiblock-device-for-rootfs.patch
new file mode 100644
index 0000000000..cb2d525610
--- /dev/null
+++ b/target/linux/generic/pending-5.4/491-ubi-auto-create-ubiblock-device-for-rootfs.patch
@@ -0,0 +1,66 @@
+From: Daniel Golle <daniel@makrotopia.org>
+Subject: ubi: auto-create ubiblock device for rootfs
+
+Signed-off-by: Daniel Golle <daniel@makrotopia.org>
+---
+ drivers/mtd/ubi/block.c | 42 ++++++++++++++++++++++++++++++++++++++++++
+ 1 file changed, 42 insertions(+)
+
+--- a/drivers/mtd/ubi/block.c
++++ b/drivers/mtd/ubi/block.c
+@@ -633,6 +633,44 @@ static void __init ubiblock_create_from_
+ 	}
+ }
+ 
++#define UBIFS_NODE_MAGIC  0x06101831
++static inline int ubi_vol_is_ubifs(struct ubi_volume_desc *desc)
++{
++	int ret;
++	uint32_t magic_of, magic;
++	ret = ubi_read(desc, 0, (char *)&magic_of, 0, 4);
++	if (ret)
++		return 0;
++	magic = le32_to_cpu(magic_of);
++	return magic == UBIFS_NODE_MAGIC;
++}
++
++static void __init ubiblock_create_auto_rootfs(void)
++{
++	int ubi_num, ret, is_ubifs;
++	struct ubi_volume_desc *desc;
++	struct ubi_volume_info vi;
++
++	for (ubi_num = 0; ubi_num < UBI_MAX_DEVICES; ubi_num++) {
++		desc = ubi_open_volume_nm(ubi_num, "rootfs", UBI_READONLY);
++		if (IS_ERR(desc))
++			continue;
++
++		ubi_get_volume_info(desc, &vi);
++		is_ubifs = ubi_vol_is_ubifs(desc);
++		ubi_close_volume(desc);
++		if (is_ubifs)
++			break;
++
++		ret = ubiblock_create(&vi);
++		if (ret)
++			pr_err("UBI error: block: can't add '%s' volume, err=%d\n",
++				vi.name, ret);
++		/* always break if we get here */
++		break;
++	}
++}
++
+ static void ubiblock_remove_all(void)
+ {
+ 	struct ubiblock *next;
+@@ -665,6 +703,10 @@ int __init ubiblock_init(void)
+ 	 */
+ 	ubiblock_create_from_param();
+ 
++	/* auto-attach "rootfs" volume if existing and non-ubifs */
++	if (IS_ENABLED(CONFIG_MTD_ROOTFS_ROOT_DEV))
++		ubiblock_create_auto_rootfs();
++
+ 	/*
+ 	 * Block devices are only created upon user requests, so we ignore
+ 	 * existing volumes.