[RFC 1/1] ubi: An interface is added for dump the mapping between LEBs and PEBs
From: ZhaoLong Wang
Date: Sat Jul 22 2023 - 06:26:15 EST
A debugfs interface named "detailed_eba_table_info" is added to view
the PEB and LEB mapping information of all volumes on a UBI device.
$ cat /sys/kernel/debug/ubi/ubi1/detailed_eba_table_info
========= vol_name:"test_volA",id:2 ========
logical_block_number physical_block_number
0 274
1 275
2 276
3 277
4 278
......
========= vol_name:"test_volB",id:3 ========
logical_block_number physical_block_number
0 619
1 613
2 614
3 (unmaped)
4 622
......
Signed-off-by: ZhaoLong Wang <wangzhaolong1@xxxxxxxxxx>
---
drivers/mtd/ubi/debug.c | 104 ++++++++++++++++++++++++++++++++++++++++
drivers/mtd/ubi/eba.c | 24 ----------
drivers/mtd/ubi/ubi.h | 24 ++++++++++
3 files changed, 128 insertions(+), 24 deletions(-)
diff --git a/drivers/mtd/ubi/debug.c b/drivers/mtd/ubi/debug.c
index 27168f511d6d..c6be9450b509 100644
--- a/drivers/mtd/ubi/debug.c
+++ b/drivers/mtd/ubi/debug.c
@@ -386,6 +386,7 @@ static const struct file_operations dfs_fops = {
.owner = THIS_MODULE,
};
+
/* As long as the position is less then that total number of erase blocks,
* we still have more to print.
*/
@@ -493,6 +494,106 @@ static const struct file_operations eraseblk_count_fops = {
.release = eraseblk_count_release,
};
+static void *eba_table_seq_start(struct seq_file *s, loff_t *pos)
+{
+ int volumes_length = UBI_MAX_VOLUMES + UBI_INT_VOL_COUNT;
+
+ if (*pos >= 0 && *pos < volumes_length)
+ return pos;
+
+ return NULL;
+}
+
+static void *eba_table_seq_next(struct seq_file *s, void *v, loff_t *pos)
+{
+ int volumes_length = UBI_MAX_VOLUMES + UBI_INT_VOL_COUNT;
+
+ (*pos)++;
+
+ if (*pos >= 0 && *pos < volumes_length)
+ return pos;
+
+ return NULL;
+}
+
+static void eba_table_seq_stop(struct seq_file *s, void *v)
+{
+}
+
+static int eba_table_seq_show(struct seq_file *s, void *iter)
+{
+ struct ubi_device *ubi = s->private;
+ int *vol_idx = iter;
+ struct ubi_volume *vol;
+ int lnum, pnum, vol_id;
+
+ vol = ubi->volumes[*vol_idx];
+ if (vol == NULL)
+ return 0;
+
+ vol_id = vol->vol_id;
+ seq_printf(s, "========= vol_name:\"%s\",id:%d ========\n", vol->name, vol_id);
+ seq_puts(s, "logical_block_number\tphysical_block_number\n");
+ spin_lock(&ubi->volumes_lock);
+ for (lnum = 0; lnum < vol->reserved_pebs; ++lnum) {
+ pnum = vol->eba_tbl->entries[lnum].pnum;
+ if (pnum >= 0)
+ seq_printf(s, "%-22d\t %-11d\n", lnum, pnum);
+ else
+ seq_printf(s, "%-22d\t(unmaped)\n", lnum);
+ }
+ spin_unlock(&ubi->volumes_lock);
+
+ return 0;
+}
+
+static const struct seq_operations eba_table_seq_ops = {
+ .start = eba_table_seq_start,
+ .next = eba_table_seq_next,
+ .stop = eba_table_seq_stop,
+ .show = eba_table_seq_show
+};
+
+static int eba_table_open(struct inode *inode, struct file *f)
+{
+ struct seq_file *s;
+ int err;
+
+ err = seq_open(f, &eba_table_seq_ops);
+ if (err)
+ return err;
+
+ s = f->private_data;
+ s->private = ubi_get_device((unsigned long)inode->i_private);
+
+ if (!s->private)
+ return -ENODEV;
+ else
+ return 0;
+}
+
+static int eba_table_release(struct inode *inode, struct file *f)
+{
+ struct seq_file *s = f->private_data;
+ struct ubi_device *ubi = s->private;
+
+ ubi_put_device(ubi);
+
+ return seq_release(inode, f);
+}
+
+/* File operations for UBI debugfs files which to read
+ * eba_tbl to help developer get the map status of ubi
+ * volumes
+ */
+static const struct file_operations eba_table_fops = {
+ .owner = THIS_MODULE,
+ .open = eba_table_open,
+ .read = seq_read,
+ .llseek = no_llseek,
+ .release = eba_table_release,
+};
+
/**
* ubi_debugfs_init_dev - initialize debugfs for an UBI device.
* @ubi: UBI device description object
@@ -556,6 +657,9 @@ int ubi_debugfs_init_dev(struct ubi_device *ubi)
mode, d->dfs_dir,
(void *)ubi_num, &dfs_fops);
+ debugfs_create_file("detailed_eba_table_info", S_IRUSR, d->dfs_dir,
+ (void *)ubi_num, &eba_table_fops);
+
debugfs_create_file("detailed_erase_block_info", S_IRUSR, d->dfs_dir,
(void *)ubi_num, &eraseblk_count_fops);
diff --git a/drivers/mtd/ubi/eba.c b/drivers/mtd/ubi/eba.c
index 655ff41863e2..c856ea73a67c 100644
--- a/drivers/mtd/ubi/eba.c
+++ b/drivers/mtd/ubi/eba.c
@@ -36,30 +36,6 @@
/* Number of physical eraseblocks reserved for atomic LEB change operation */
#define EBA_RESERVED_PEBS 1
-/**
- * struct ubi_eba_entry - structure encoding a single LEB -> PEB association
- * @pnum: the physical eraseblock number attached to the LEB
- *
- * This structure is encoding a LEB -> PEB association. Note that the LEB
- * number is not stored here, because it is the index used to access the
- * entries table.
- */
-struct ubi_eba_entry {
- int pnum;
-};
-
-/**
- * struct ubi_eba_table - LEB -> PEB association information
- * @entries: the LEB to PEB mapping (one entry per LEB).
- *
- * This structure is private to the EBA logic and should be kept here.
- * It is encoding the LEB to PEB association table, and is subject to
- * changes.
- */
-struct ubi_eba_table {
- struct ubi_eba_entry *entries;
-};
-
/**
* ubi_next_sqnum - get next sequence number.
* @ubi: UBI device description object
diff --git a/drivers/mtd/ubi/ubi.h b/drivers/mtd/ubi/ubi.h
index c8f1bd4fa100..1457657901df 100644
--- a/drivers/mtd/ubi/ubi.h
+++ b/drivers/mtd/ubi/ubi.h
@@ -153,6 +153,30 @@ enum {
POWER_CUT_VID_WRITE = 0x02,
};
+/**
+ * struct ubi_eba_entry - structure encoding a single LEB -> PEB association
+ * @pnum: the physical eraseblock number attached to the LEB
+ *
+ * This structure is encoding a LEB -> PEB association. Note that the LEB
+ * number is not stored here, because it is the index used to access the
+ * entries table.
+ */
+struct ubi_eba_entry {
+ int pnum;
+};
+
+/**
+ * struct ubi_eba_table - LEB -> PEB association information
+ * @entries: the LEB to PEB mapping (one entry per LEB).
+ *
+ * This structure is private to the EBA logic and should be kept here.
+ * It is encoding the LEB to PEB association table, and is subject to
+ * changes.
+ */
+struct ubi_eba_table {
+ struct ubi_eba_entry *entries;
+};
+
/**
* struct ubi_vid_io_buf - VID buffer used to read/write VID info to/from the
* flash.
--
2.31.1