--- zzzz-none-000/linux-5.4.213/drivers/mtd/mtdcore.c	2022-09-15 10:04:56.000000000 +0000
+++ miami-7690-761/linux-5.4.213/drivers/mtd/mtdcore.c	2024-05-29 11:19:52.000000000 +0000
@@ -27,6 +27,7 @@
 #include <linux/reboot.h>
 #include <linux/leds.h>
 #include <linux/debugfs.h>
+#include <linux/root_dev.h>
 #include <linux/nvmem-provider.h>
 
 #include <linux/mtd/mtd.h>
@@ -35,7 +36,9 @@
 #include "mtdcore.h"
 
 struct backing_dev_info *mtd_bdi;
-
+#ifdef CONFIG_KASAN
+bool nand_device_suspended = false;
+#endif
 #ifdef CONFIG_PM_SLEEP
 
 static int mtd_cls_suspend(struct device *dev)
@@ -432,9 +435,12 @@
 			       void *cmd)
 {
 	struct mtd_info *mtd;
-
 	mtd = container_of(n, struct mtd_info, reboot_notifier);
 	mtd->_reboot(mtd);
+#ifdef CONFIG_KASAN
+	nand_device_suspended = true;
+	pr_info("NAND device suspended. Ignoring further read/write requests\n");
+#endif
 
 	return NOTIFY_DONE;
 }
@@ -543,6 +549,7 @@
 }
 EXPORT_SYMBOL_GPL(mtd_pairing_groups);
 
+#ifdef CONFIG_MTD_SUPPORTS_NVMEM
 static int mtd_nvmem_reg_read(void *priv, unsigned int offset,
 			      void *val, size_t bytes)
 {
@@ -587,6 +594,7 @@
 
 	return 0;
 }
+#endif
 
 /**
  *	add_mtd_device - register an MTD device
@@ -676,10 +684,12 @@
 	if (error)
 		goto fail_added;
 
+#ifdef CONFIG_MTD_SUPPORTS_NVMEM
 	/* Add the nvmem provider */
 	error = mtd_nvmem_add(mtd);
 	if (error)
 		goto fail_nvmem_add;
+#endif
 
 	mtd_debugfs_populate(mtd);
 
@@ -698,10 +708,21 @@
 	   of this try_ nonsense, and no bitching about it
 	   either. :) */
 	__module_get(THIS_MODULE);
+
+	if (!strcmp(mtd->name, "rootfs") &&
+	    IS_ENABLED(CONFIG_MTD_ROOTFS_ROOT_DEV) &&
+	    ROOT_DEV == 0) {
+		pr_notice("mtd: device %d (%s) set to be root filesystem\n",
+			  mtd->index, mtd->name);
+		ROOT_DEV = MKDEV(MTD_BLOCK_MAJOR, mtd->index);
+	}
+
 	return 0;
 
+#ifdef CONFIG_MTD_SUPPORTS_NVMEM
 fail_nvmem_add:
 	device_unregister(&mtd->dev);
+#endif
 fail_added:
 	of_node_put(mtd_get_of_node(mtd));
 	idr_remove(&mtd_idr, i);
@@ -744,9 +765,11 @@
 	} else {
 		debugfs_remove_recursive(mtd->dbg.dfs_dir);
 
+#ifdef CONFIG_MTD_SUPPORTS_NVMEM
 		/* Try to remove the NVMEM provider */
 		if (mtd->nvmem)
 			nvmem_unregister(mtd->nvmem);
+#endif
 
 		device_unregister(&mtd->dev);
 
@@ -1042,6 +1065,44 @@
 }
 EXPORT_SYMBOL_GPL(get_mtd_device_nm);
 
+/**
+ *	get_mtd_device_by_node - obtain a validated handle for an MTD device
+ *	by of_node
+ *	@of_node: OF node of MTD device to open
+ *
+ *	This function returns MTD device description structure in case of
+ *	success and an error code in case of failure.
+ */
+struct mtd_info *get_mtd_device_by_node(const struct device_node *of_node)
+{
+	int err = -ENODEV;
+	struct mtd_info *mtd = NULL, *other;
+
+	mutex_lock(&mtd_table_mutex);
+
+	mtd_for_each_device(other) {
+		if (of_node == other->dev.of_node) {
+			mtd = other;
+			break;
+		}
+	}
+
+	if (!mtd)
+		goto out_unlock;
+
+	err = __get_mtd_device(mtd);
+	if (err)
+		goto out_unlock;
+
+	mutex_unlock(&mtd_table_mutex);
+	return mtd;
+
+out_unlock:
+	mutex_unlock(&mtd_table_mutex);
+	return ERR_PTR(err);
+}
+EXPORT_SYMBOL_GPL(get_mtd_device_by_node);
+
 void put_mtd_device(struct mtd_info *mtd)
 {
 	mutex_lock(&mtd_table_mutex);
@@ -1933,6 +1994,42 @@
 	mutex_unlock(&mtd_table_mutex);
 	return 0;
 }
+
+#if defined(CONFIG_AVM_ENHANCED)
+static struct proc_dir_entry *proc_bbt_mtd;
+static int mtd_bbt_proc_show(struct seq_file *m, void *v)
+{
+	struct mtd_info *mtd;
+
+	mutex_lock(&mtd_table_mutex);
+	mtd_for_each_device(mtd) {
+		if (mtd->_block_isbad) {
+			uint64_t i;
+			unsigned int badblocks=0;
+			for (i = 0; i < mtd->size; i += mtd->erasesize) {
+				if (mtd->_block_isbad(mtd, i) && ((badblocks+1)>badblocks) )
+					badblocks++;
+			}
+			seq_printf(m, "mtd%d: %u bad blocks\n", mtd->index, badblocks);
+		}
+	}
+	mutex_unlock(&mtd_table_mutex);
+	return 0;
+}
+
+static int mtd_bbt_proc_open(struct inode *inode, struct file *file)
+{
+	return single_open(file, mtd_bbt_proc_show, NULL);
+}
+
+static const struct file_operations mtd_bbt_proc_ops = {
+	.open		= mtd_bbt_proc_open,
+	.read		= seq_read,
+	.llseek		= seq_lseek,
+	.release	= single_release,
+};
+#endif /*--- #if #defined(CONFIG_AVM_ENHANCED) ---*/
+
 #endif /* CONFIG_PROC_FS */
 
 /*====================================================================*/
@@ -1977,6 +2074,10 @@
 
 	proc_mtd = proc_create_single("mtd", 0, NULL, mtd_proc_show);
 
+#if defined(CONFIG_AVM_ENHANCED)
+	proc_bbt_mtd = proc_create("avm/mtd_bbt", 0, NULL, &mtd_bbt_proc_ops);
+#endif
+
 	ret = init_mtdchar();
 	if (ret)
 		goto out_procfs;
@@ -1988,6 +2089,12 @@
 out_procfs:
 	if (proc_mtd)
 		remove_proc_entry("mtd", NULL);
+
+#if defined(CONFIG_AVM_ENHANCED)
+	if (proc_bbt_mtd)
+		remove_proc_entry("mtd_bbt", NULL);
+#endif
+
 	bdi_put(mtd_bdi);
 err_bdi:
 	class_unregister(&mtd_class);
@@ -2002,6 +2109,12 @@
 	cleanup_mtdchar();
 	if (proc_mtd)
 		remove_proc_entry("mtd", NULL);
+
+#if defined(CONFIG_AVM_ENHANCED)
+	if (proc_bbt_mtd)
+		remove_proc_entry("mtd_bbt", NULL);
+#endif
+
 	class_unregister(&mtd_class);
 	bdi_put(mtd_bdi);
 	idr_destroy(&mtd_idr);