+static int nandsim_debugfs_show(struct seq_file *m, void *private)
+{
+ unsigned long wmin = -1, wmax = 0, avg;
+ unsigned long deciles[10], decile_max[10], tot = 0;
+ unsigned int i;
+
+ /* Calc wear stats */
+ for (i = 0; i < wear_eb_count; ++i) {
+ unsigned long wear = erase_block_wear[i];
+ if (wear < wmin)
+ wmin = wear;
+ if (wear > wmax)
+ wmax = wear;
+ tot += wear;
+ }
+
+ for (i = 0; i < 9; ++i) {
+ deciles[i] = 0;
+ decile_max[i] = (wmax * (i + 1) + 5) / 10;
+ }
+ deciles[9] = 0;
+ decile_max[9] = wmax;
+ for (i = 0; i < wear_eb_count; ++i) {
+ int d;
+ unsigned long wear = erase_block_wear[i];
+ for (d = 0; d < 10; ++d)
+ if (wear <= decile_max[d]) {
+ deciles[d] += 1;
+ break;
+ }
+ }
+ avg = tot / wear_eb_count;
+
+ /* Output wear report */
+ seq_printf(m, "Total numbers of erases: %lu\n", tot);
+ seq_printf(m, "Number of erase blocks: %u\n", wear_eb_count);
+ seq_printf(m, "Average number of erases: %lu\n", avg);
+ seq_printf(m, "Maximum number of erases: %lu\n", wmax);
+ seq_printf(m, "Minimum number of erases: %lu\n", wmin);
+ for (i = 0; i < 10; ++i) {
+ unsigned long from = (i ? decile_max[i - 1] + 1 : 0);
+ if (from > decile_max[i])
+ continue;
+ seq_printf(m, "Number of ebs with erase counts from %lu to %lu : %lu\n",
+ from,
+ decile_max[i],
+ deciles[i]);
+ }
+
+ return 0;
+}
+
+static int nandsim_debugfs_open(struct inode *inode, struct file *file)
+{
+ return single_open(file, nandsim_debugfs_show, inode->i_private);
+}
+
+static const struct file_operations dfs_fops = {
+ .open = nandsim_debugfs_open,
+ .read = seq_read,
+ .llseek = seq_lseek,
+ .release = single_release,
+};
+
+/**
+ * nandsim_debugfs_create - initialize debugfs
+ * @dev: nandsim device description object
+ *
+ * This function creates all debugfs files for UBI device @ubi. Returns zero in
+ * case of success and a negative error code in case of failure.
+ */
+static int nandsim_debugfs_create(struct nandsim *dev)
+{
+ struct nandsim_debug_info *dbg = &dev->dbg;
+ struct dentry *dent;
+ int err;
+
+ if (!IS_ENABLED(CONFIG_DEBUG_FS))
+ return 0;
+
+ dent = debugfs_create_dir("nandsim", NULL);
+ if (IS_ERR_OR_NULL(dent)) {
+ int err = dent ? -ENODEV : PTR_ERR(dent);
+
+ NS_ERR("cannot create \"nandsim\" debugfs directory, err %d\n",
+ err);
+ return err;
+ }
+ dbg->dfs_root = dent;
+
+ dent = debugfs_create_file("wear_report", S_IRUSR,
+ dbg->dfs_root, dev, &dfs_fops);
+ if (IS_ERR_OR_NULL(dent))
+ goto out_remove;
+ dbg->dfs_wear_report = dent;
+
+ return 0;
+
+out_remove:
+ debugfs_remove_recursive(dbg->dfs_root);
+ err = dent ? PTR_ERR(dent) : -ENODEV;
+ return err;
+}
+
+/**
+ * nandsim_debugfs_remove - destroy all debugfs files
+ */
+static void nandsim_debugfs_remove(struct nandsim *ns)
+{
+ if (IS_ENABLED(CONFIG_DEBUG_FS))
+ debugfs_remove_recursive(ns->dbg.dfs_root);
+}
+