UBI: Add initial support for fastmap self checks

Using this debugfs knob fastmap self checks can be controlled.
Signed-off-by: Richard Weinberger <richard@nod.at>
Reviewed-by: Tanya Brokhman <tlinder@codeaurora.org>

drivers/mtd/ubi/debug.c

@@ -275,6 +275,8 @@ static ssize_t dfs_file_read(struct file *file, char __user *user_buf,
 		val = d->chk_gen;
 	else if (dent == d->dfs_chk_io)
 		val = d->chk_io;
+	else if (dent == d->dfs_chk_fastmap)
+		val = d->chk_fastmap;
 	else if (dent == d->dfs_disable_bgt)
 		val = d->disable_bgt;
 	else if (dent == d->dfs_emulate_bitflips)
@@ -336,6 +338,8 @@ static ssize_t dfs_file_write(struct file *file, const char __user *user_buf,
 		d->chk_gen = val;
 	else if (dent == d->dfs_chk_io)
 		d->chk_io = val;
+	else if (dent == d->dfs_chk_fastmap)
+		d->chk_fastmap = val;
 	else if (dent == d->dfs_disable_bgt)
 		d->disable_bgt = val;
 	else if (dent == d->dfs_emulate_bitflips)
@@ -406,6 +410,13 @@ int ubi_debugfs_init_dev(struct ubi_device *ubi)
 		goto out_remove;
 	d->dfs_chk_io = dent;
 
+	fname = "chk_fastmap";
+	dent = debugfs_create_file(fname, S_IWUSR, d->dfs_dir, (void *)ubi_num,
+				   &dfs_fops);
+	if (IS_ERR_OR_NULL(dent))
+		goto out_remove;
+	d->dfs_chk_fastmap = dent;
+
 	fname = "tst_disable_bgt";
 	dent = debugfs_create_file(fname, S_IWUSR, d->dfs_dir, (void *)ubi_num,
 				   &dfs_fops);

drivers/mtd/ubi/debug.h

@@ -127,4 +127,9 @@ static inline int ubi_dbg_chk_gen(const struct ubi_device *ubi)
 {
 	return ubi->dbg.chk_gen;
 }
+
+static inline int ubi_dbg_chk_fastmap(const struct ubi_device *ubi)
+{
+	return ubi->dbg.chk_fastmap;
+}
 #endif /* !__UBI_DEBUG_H__ */

drivers/mtd/ubi/ubi.h

@@ -356,6 +356,7 @@ struct ubi_wl_entry;
  *
  * @chk_gen: if UBI general extra checks are enabled
  * @chk_io: if UBI I/O extra checks are enabled
+ * @chk_fastmap: if UBI fastmap extra checks are enabled
  * @disable_bgt: disable the background task for testing purposes
  * @emulate_bitflips: emulate bit-flips for testing purposes
  * @emulate_io_failures: emulate write/erase failures for testing purposes
@@ -363,6 +364,7 @@ struct ubi_wl_entry;
  * @dfs_dir: direntry object of the UBI device debugfs directory
  * @dfs_chk_gen: debugfs knob to enable UBI general extra checks
  * @dfs_chk_io: debugfs knob to enable UBI I/O extra checks
+ * @dfs_chk_fastmap: debugfs knob to enable UBI fastmap extra checks
  * @dfs_disable_bgt: debugfs knob to disable the background task
  * @dfs_emulate_bitflips: debugfs knob to emulate bit-flips
  * @dfs_emulate_io_failures: debugfs knob to emulate write/erase failures
@@ -370,6 +372,7 @@ struct ubi_wl_entry;
 struct ubi_debug_info {
 	unsigned int chk_gen:1;
 	unsigned int chk_io:1;
+	unsigned int chk_fastmap:1;
 	unsigned int disable_bgt:1;
 	unsigned int emulate_bitflips:1;
 	unsigned int emulate_io_failures:1;
@@ -377,6 +380,7 @@ struct ubi_debug_info {
 	struct dentry *dfs_dir;
 	struct dentry *dfs_chk_gen;
 	struct dentry *dfs_chk_io;
+	struct dentry *dfs_chk_fastmap;
 	struct dentry *dfs_disable_bgt;
 	struct dentry *dfs_emulate_bitflips;
 	struct dentry *dfs_emulate_io_failures;