diff mbox

[v2] UBI: add debugfs file for tracking PEB state

Message ID 1490379824-1872-1-git-send-email-zach.brown@ni.com
State Superseded
Delegated to: Richard Weinberger
Headers show

Commit Message

Zach Brown March 24, 2017, 6:23 p.m. UTC
From: Ben Shelton <ben.shelton@ni.com>

Add a file under debugfs to allow easy access to the erase count for
each physical erase block on an UBI device.  This is useful when
debugging data integrity issues with UBIFS on NAND flash devices.

Signed-off-by: Ben Shelton <ben.shelton@ni.com>
Signed-off-by: Zach Brown <zach.brown@ni.com>

v2:
* If ubi_io_is_bad eraseblk_count_seq_show just returns the err.
* if ubi->lookuptbl returns null, its no longer treated as an error
  instead info for that block is not printeded
* Removed check for UBI_MAX_ERASECOUNTER since it is impossible to hit
* Removed block state from print, if a block is printed then it is good and if
  it is not printed, then it is bad.

---
 drivers/mtd/ubi/debug.c | 126 +++++++++++++++++++++++++++++++++++++++++++++++-
 1 file changed, 125 insertions(+), 1 deletion(-)

--
2.7.4

Comments

kernel test robot March 25, 2017, 3:23 p.m. UTC | #1
Hi Ben,

[auto build test WARNING on v4.9-rc8]
[also build test WARNING on next-20170324]
[if your patch is applied to the wrong git tree, please drop us a note to help improve the system]

url:    https://github.com/0day-ci/linux/commits/Zach-Brown/UBI-add-debugfs-file-for-tracking-PEB-state/20170325-205127
config: x86_64-rhel (attached as .config)
compiler: gcc-6 (Debian 6.2.0-3) 6.2.0 20160901
reproduce:
        # save the attached .config to linux build tree
        make ARCH=x86_64 

All warnings (new ones prefixed by >>):

   drivers/mtd/ubi/debug.c: In function 'eraseblk_count_seq_show':
>> drivers/mtd/ubi/debug.c:465:19: warning: comparison of constant '0' with boolean expression is always false [-Wbool-compare]
     if (!erase_count < 0)
                      ^
>> drivers/mtd/ubi/debug.c:465:19: warning: logical not is only applied to the left hand side of comparison [-Wlogical-not-parentheses]

vim +/0 +465 drivers/mtd/ubi/debug.c

   449				 "physical_block_number\terase_count\tblock_status\tread_status\n");
   450			return 0;
   451		}
   452	
   453		err = ubi_io_is_bad(ubi, *block_number);
   454		if (err)
   455			return err;
   456	
   457		spin_lock(&ubi->wl_lock);
   458	
   459		wl = ubi->lookuptbl[*block_number];
   460		if (wl)
   461			erase_count = wl->ec;
   462	
   463		spin_unlock(&ubi->wl_lock);
   464	
 > 465		if (!erase_count < 0)
   466			return 0;
   467	
   468		seq_printf(s, "%-22d\t%-11d\n", *block_number, erase_count);
   469	
   470		return 0;
   471	}
   472	
   473	static const struct seq_operations eraseblk_count_seq_ops = {

---
0-DAY kernel test infrastructure                Open Source Technology Center
https://lists.01.org/pipermail/kbuild-all                   Intel Corporation
diff mbox

Patch

diff --git a/drivers/mtd/ubi/debug.c b/drivers/mtd/ubi/debug.c
index f101a49..5f2b65d 100644
--- a/drivers/mtd/ubi/debug.c
+++ b/drivers/mtd/ubi/debug.c
@@ -22,6 +22,7 @@ 
 #include <linux/debugfs.h>
 #include <linux/uaccess.h>
 #include <linux/module.h>
+#include <linux/seq_file.h>


 /**
@@ -386,7 +387,9 @@  static ssize_t dfs_file_write(struct file *file, const char __user *user_buf,
 	return count;
 }

-/* File operations for all UBI debugfs files */
+/* File operations for all UBI debugfs files except
+ * detailed_erase_block_info
+ */
 static const struct file_operations dfs_fops = {
 	.read   = dfs_file_read,
 	.write  = dfs_file_write,
@@ -395,6 +398,121 @@  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.
+ */
+static void *eraseblk_count_seq_start(struct seq_file *s, loff_t *pos)
+{
+	struct ubi_device *ubi = s->private;
+
+	if (*pos == 0)
+		return SEQ_START_TOKEN;
+
+	if (*pos < ubi->peb_count)
+		return pos;
+
+	return NULL;
+}
+
+/* Since we are using the position as the iterator, we just need to check if we
+ * are done and increment the position.
+ */
+static void *eraseblk_count_seq_next(struct seq_file *s, void *v, loff_t *pos)
+{
+	struct ubi_device *ubi = s->private;
+
+	if (v == SEQ_START_TOKEN)
+		return pos;
+	(*pos)++;
+
+	if (*pos < ubi->peb_count)
+		return pos;
+
+	return NULL;
+}
+
+static void eraseblk_count_seq_stop(struct seq_file *s, void *v)
+{
+}
+
+static int eraseblk_count_seq_show(struct seq_file *s, void *iter)
+{
+	struct ubi_device *ubi = s->private;
+	struct ubi_wl_entry *wl;
+	int *block_number = iter;
+	int erase_count = -1;
+	int err;
+
+	/* If this is the start, print a header */
+	if (iter == SEQ_START_TOKEN) {
+		seq_puts(s,
+			 "physical_block_number\terase_count\tblock_status\tread_status\n");
+		return 0;
+	}
+
+	err = ubi_io_is_bad(ubi, *block_number);
+	if (err)
+		return err;
+
+	spin_lock(&ubi->wl_lock);
+
+	wl = ubi->lookuptbl[*block_number];
+	if (wl)
+		erase_count = wl->ec;
+
+	spin_unlock(&ubi->wl_lock);
+
+	if (!erase_count < 0)
+		return 0;
+
+	seq_printf(s, "%-22d\t%-11d\n", *block_number, erase_count);
+
+	return 0;
+}
+
+static const struct seq_operations eraseblk_count_seq_ops = {
+	.start = eraseblk_count_seq_start,
+	.next = eraseblk_count_seq_next,
+	.stop = eraseblk_count_seq_stop,
+	.show = eraseblk_count_seq_show
+};
+
+static int eraseblk_count_open(struct inode *inode, struct file *f)
+{
+	struct seq_file *s;
+	int err;
+
+	err = seq_open(f, &eraseblk_count_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 eraseblk_count_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);
+}
+
+static const struct file_operations eraseblk_count_fops = {
+	.owner = THIS_MODULE,
+	.open = eraseblk_count_open,
+	.read = seq_read,
+	.llseek = seq_lseek,
+	.release = eraseblk_count_release,
+};
+
 /**
  * ubi_debugfs_init_dev - initialize debugfs for an UBI device.
  * @ubi: UBI device description object
@@ -491,6 +609,12 @@  int ubi_debugfs_init_dev(struct ubi_device *ubi)
 		goto out_remove;
 	d->dfs_power_cut_max = dent;

+	fname = "detailed_erase_block_info";
+	dent = debugfs_create_file(fname, S_IRUSR, d->dfs_dir, (void *)ubi_num,
+				   &eraseblk_count_fops);
+	if (IS_ERR_OR_NULL(dent))
+		goto out_remove;
+
 	return 0;

 out_remove: