From 99ba04053a3712498327bd147c22a9877100a904 Mon Sep 17 00:00:00 2001
From: Nicolas Ferre <nicolas.ferre@atmel.com>
Date: Thu, 27 Nov 2008 17:23:49 +0100
Subject: mmc: at91_mci: reorder timer setup and mmc_add_host() call

As said in function comment mmc_add_host() requires that:
"The host must be prepared to start servicing requests
before this function completes."

During this function, at91_mci_request() can be invoqued
without timer beeing setup leading to a kernel Oops.
This has been reported inserting this driver as a module.

Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Reported-by: Wu Xuan <wux@landicorp.com>
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
---
 drivers/mmc/host/at91_mci.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/mmc/host/at91_mci.c b/drivers/mmc/host/at91_mci.c
index 1f8b5b36222c..e556d42cc45a 100644
--- a/drivers/mmc/host/at91_mci.c
+++ b/drivers/mmc/host/at91_mci.c
@@ -1088,6 +1088,8 @@ static int __init at91_mci_probe(struct platform_device *pdev)
 		goto fail0;
 	}
 
+	setup_timer(&host->timer, at91_timeout_timer, (unsigned long)host);
+
 	platform_set_drvdata(pdev, mmc);
 
 	/*
@@ -1101,8 +1103,6 @@ static int __init at91_mci_probe(struct platform_device *pdev)
 
 	mmc_add_host(mmc);
 
-	setup_timer(&host->timer, at91_timeout_timer, (unsigned long)host);
-
 	/*
 	 * monitor card insertion/removal if we can
 	 */
-- 
cgit v1.2.3


From 98444d3dd975653a4a970ecc0dfc30918da92f60 Mon Sep 17 00:00:00 2001
From: Sascha Sommer <saschasommer@freenet.de>
Date: Sat, 29 Nov 2008 07:51:19 +0100
Subject: sdricoh_cs: Add support for Bay Controller devices

Some Ricoh SD card readers seems to advertise themselves slightly differently.
This patches the driver to will recognise an additional product id, and it
appears to work perfectly.

  % pccardctl info
  PRODID_1="RICOH"
  PRODID_2="Bay Controller"
  PRODID_3=""
  PRODID_4=""
  MANFID=0000,0000

Signed-off-by: Charles Lowe <aquasync@gmail.com>
Acked-by: Sascha Sommer <saschasommer@freenet.de>
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
---
 drivers/mmc/host/sdricoh_cs.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/mmc/host/sdricoh_cs.c b/drivers/mmc/host/sdricoh_cs.c
index 1df44d966bdb..435863370017 100644
--- a/drivers/mmc/host/sdricoh_cs.c
+++ b/drivers/mmc/host/sdricoh_cs.c
@@ -82,6 +82,8 @@ static struct pcmcia_device_id pcmcia_ids[] = {
 	/* vendor and device strings followed by their crc32 hashes */
 	PCMCIA_DEVICE_PROD_ID12("RICOH", "Bay1Controller", 0xd9f522ed,
 				0xc3901202),
+	PCMCIA_DEVICE_PROD_ID12("RICOH", "Bay Controller", 0xd9f522ed,
+				0xace80909),
 	PCMCIA_DEVICE_NULL,
 };
 
-- 
cgit v1.2.3


From 062e4fee4400f283307cf8ac1b7931c939010229 Mon Sep 17 00:00:00 2001
From: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Date: Sun, 26 Oct 2008 16:58:25 +0200
Subject: UBIFS: slight compression optimization

If data does not compress, it is better to leave it uncompressed
because we'll read it faster then. So do not compress data if we
save less than 64 bytes.

Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
---
 fs/ubifs/compress.c    | 6 +++---
 fs/ubifs/ubifs-media.h | 7 +++++++
 2 files changed, 10 insertions(+), 3 deletions(-)

diff --git a/fs/ubifs/compress.c b/fs/ubifs/compress.c
index a0ada596b17c..6414d50780e1 100644
--- a/fs/ubifs/compress.c
+++ b/fs/ubifs/compress.c
@@ -119,10 +119,10 @@ void ubifs_compress(const void *in_buf, int in_len, void *out_buf, int *out_len,
 	}
 
 	/*
-	 * Presently, we just require that compression results in less data,
-	 * rather than any defined minimum compression ratio or amount.
+	 * If the data compressed only slightly, it is better to leave it
+	 * uncompressed to improve read speed.
 	 */
-	if (ALIGN(*out_len, 8) >= ALIGN(in_len, 8))
+	if (in_len - *out_len < UBIFS_MIN_COMPRESS_DIFF)
 		goto no_compr;
 
 	return;
diff --git a/fs/ubifs/ubifs-media.h b/fs/ubifs/ubifs-media.h
index 0b378042a3a2..b25fc36cf72f 100644
--- a/fs/ubifs/ubifs-media.h
+++ b/fs/ubifs/ubifs-media.h
@@ -51,6 +51,13 @@
  */
 #define UBIFS_MIN_COMPR_LEN 128
 
+/*
+ * If compressed data length is less than %UBIFS_MIN_COMPRESS_DIFF bytes
+ * shorter than uncompressed data length, UBIFS preferes to leave this data
+ * node uncompress, because it'll be read faster.
+ */
+#define UBIFS_MIN_COMPRESS_DIFF 64
+
 /* Root inode number */
 #define UBIFS_ROOT_INO 1
 
-- 
cgit v1.2.3


From a1dc080c27ec8ea7ca1c8a9b499362a71ebff792 Mon Sep 17 00:00:00 2001
From: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Date: Sat, 1 Nov 2008 14:20:50 +0200
Subject: UBIFS: use bit-fields to store compression type

Save a 4 bytes of RAM per 'struct inode' by stroring inode
compression type in bit-filed, instead of using 'int'.

Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
---
 fs/ubifs/super.c | 8 ++++++++
 fs/ubifs/ubifs.h | 6 +++---
 2 files changed, 11 insertions(+), 3 deletions(-)

diff --git a/fs/ubifs/super.c b/fs/ubifs/super.c
index d80b2aef42b6..21b4103271ec 100644
--- a/fs/ubifs/super.c
+++ b/fs/ubifs/super.c
@@ -2020,6 +2020,14 @@ static int __init ubifs_init(void)
 	BUILD_BUG_ON(UBIFS_INO_NODE_SZ != 160);
 	BUILD_BUG_ON(UBIFS_REF_NODE_SZ != 64);
 
+	/*
+	 * We use 2 bit wide bit-fields to store compression type, which should
+	 * be amended if more compressors are added. The bit-fields are:
+	 * @compr_type in 'struct ubifs_inode' and @default_compr in
+	 * 'struct ubifs_info'.
+	 */
+	BUILD_BUG_ON(UBIFS_COMPR_TYPES_CNT > 4);
+
 	/*
 	 * We require that PAGE_CACHE_SIZE is greater-than-or-equal-to
 	 * UBIFS_BLOCK_SIZE. It is assumed that both are powers of 2.
diff --git a/fs/ubifs/ubifs.h b/fs/ubifs/ubifs.h
index 46b172560a06..4d76aba57ee1 100644
--- a/fs/ubifs/ubifs.h
+++ b/fs/ubifs/ubifs.h
@@ -386,12 +386,12 @@ struct ubifs_inode {
 	unsigned int dirty:1;
 	unsigned int xattr:1;
 	unsigned int bulk_read:1;
+	unsigned int compr_type:2;
 	struct mutex ui_mutex;
 	spinlock_t ui_lock;
 	loff_t synced_i_size;
 	loff_t ui_size;
 	int flags;
-	int compr_type;
 	pgoff_t last_page_read;
 	pgoff_t read_in_a_row;
 	int data_len;
@@ -946,6 +946,7 @@ struct ubifs_mount_opts {
  * @no_chk_data_crc: do not check CRCs when reading data nodes (except during
  *                   recovery)
  * @bulk_read: enable bulk-reads
+ * @default_compr: default compression algorithm (%UBIFS_COMPR_LZO, etc)
  *
  * @tnc_mutex: protects the Tree Node Cache (TNC), @zroot, @cnext, @enext, and
  *             @calc_idx_sz
@@ -986,7 +987,6 @@ struct ubifs_mount_opts {
  * @main_lebs: count of LEBs in the main area
  * @main_first: first LEB of the main area
  * @main_bytes: main area size in bytes
- * @default_compr: default compression algorithm (%UBIFS_COMPR_LZO, etc)
  *
  * @key_hash_type: type of the key hash
  * @key_hash: direntry key hash function
@@ -1196,6 +1196,7 @@ struct ubifs_info {
 	unsigned int big_lpt:1;
 	unsigned int no_chk_data_crc:1;
 	unsigned int bulk_read:1;
+	unsigned int default_compr:2;
 
 	struct mutex tnc_mutex;
 	struct ubifs_zbranch zroot;
@@ -1237,7 +1238,6 @@ struct ubifs_info {
 	int main_lebs;
 	int main_first;
 	long long main_bytes;
-	int default_compr;
 
 	uint8_t key_hash_type;
 	uint32_t (*key_hash)(const char *str, int len);
-- 
cgit v1.2.3


From 553dea4dd531562688ba01c641c7f8fc7abaaf8c Mon Sep 17 00:00:00 2001
From: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Date: Sat, 1 Nov 2008 14:57:49 +0200
Subject: UBIFS: introduce compression mount options

It is very handy to be able to change default UBIFS compressor
via mount options. Introduce -o compr=<name> mount option support.
Currently only "none", "lzo" and "zlib" compressors are supported.

Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
---
 Documentation/filesystems/ubifs.txt |  3 +++
 fs/ubifs/compress.c                 |  6 ++---
 fs/ubifs/sb.c                       | 10 +++++----
 fs/ubifs/super.c                    | 44 +++++++++++++++++++++++++++++++------
 fs/ubifs/ubifs.h                    | 12 ++++++++--
 5 files changed, 59 insertions(+), 16 deletions(-)

diff --git a/Documentation/filesystems/ubifs.txt b/Documentation/filesystems/ubifs.txt
index dd84ea3c10da..2d0db5482d29 100644
--- a/Documentation/filesystems/ubifs.txt
+++ b/Documentation/filesystems/ubifs.txt
@@ -95,6 +95,9 @@ no_chk_data_crc		skip checking of CRCs on data nodes in order to
 			of this option is that corruption of the contents
 			of a file can go unnoticed.
 chk_data_crc (*)	do not skip checking CRCs on data nodes
+compr=none              override defoult comressor and set it to "none"
+compr=lzo               override defoult comressor and set it to "lzo"
+compr=zlib              override defoult comressor and set it to "zlib"
 
 
 Quick usage instructions
diff --git a/fs/ubifs/compress.c b/fs/ubifs/compress.c
index 6414d50780e1..4afb3ea24d44 100644
--- a/fs/ubifs/compress.c
+++ b/fs/ubifs/compress.c
@@ -33,7 +33,7 @@
 /* Fake description object for the "none" compressor */
 static struct ubifs_compressor none_compr = {
 	.compr_type = UBIFS_COMPR_NONE,
-	.name = "no compression",
+	.name = "none",
 	.capi_name = "",
 };
 
@@ -43,13 +43,13 @@ static DEFINE_MUTEX(lzo_mutex);
 static struct ubifs_compressor lzo_compr = {
 	.compr_type = UBIFS_COMPR_LZO,
 	.comp_mutex = &lzo_mutex,
-	.name = "LZO",
+	.name = "lzo",
 	.capi_name = "lzo",
 };
 #else
 static struct ubifs_compressor lzo_compr = {
 	.compr_type = UBIFS_COMPR_LZO,
-	.name = "LZO",
+	.name = "lzo",
 };
 #endif
 
diff --git a/fs/ubifs/sb.c b/fs/ubifs/sb.c
index 0f392351dc5a..c5da201ab54f 100644
--- a/fs/ubifs/sb.c
+++ b/fs/ubifs/sb.c
@@ -179,8 +179,11 @@ static int create_default_filesystem(struct ubifs_info *c)
 	sup->fanout        = cpu_to_le32(DEFAULT_FANOUT);
 	sup->lsave_cnt     = cpu_to_le32(c->lsave_cnt);
 	sup->fmt_version   = cpu_to_le32(UBIFS_FORMAT_VERSION);
-	sup->default_compr = cpu_to_le16(UBIFS_COMPR_LZO);
 	sup->time_gran     = cpu_to_le32(DEFAULT_TIME_GRAN);
+	if (c->mount_opts.override_compr)
+		sup->default_compr = cpu_to_le16(c->mount_opts.compr_type);
+	else
+		sup->default_compr = cpu_to_le16(UBIFS_COMPR_LZO);
 
 	generate_random_uuid(sup->uuid);
 
@@ -582,16 +585,15 @@ int ubifs_read_superblock(struct ubifs_info *c)
 	c->jhead_cnt     = le32_to_cpu(sup->jhead_cnt) + NONDATA_JHEADS_CNT;
 	c->fanout        = le32_to_cpu(sup->fanout);
 	c->lsave_cnt     = le32_to_cpu(sup->lsave_cnt);
-	c->default_compr = le16_to_cpu(sup->default_compr);
 	c->rp_size       = le64_to_cpu(sup->rp_size);
 	c->rp_uid        = le32_to_cpu(sup->rp_uid);
 	c->rp_gid        = le32_to_cpu(sup->rp_gid);
 	sup_flags        = le32_to_cpu(sup->flags);
+	if (!c->mount_opts.override_compr)
+		c->default_compr = le16_to_cpu(sup->default_compr);
 
 	c->vfs_sb->s_time_gran = le32_to_cpu(sup->time_gran);
-
 	memcpy(&c->uuid, &sup->uuid, 16);
-
 	c->big_lpt = !!(sup_flags & UBIFS_FLG_BIGLPT);
 
 	/* Automatically increase file system size to the maximum size */
diff --git a/fs/ubifs/super.c b/fs/ubifs/super.c
index 21b4103271ec..fc81022cc26d 100644
--- a/fs/ubifs/super.c
+++ b/fs/ubifs/super.c
@@ -417,6 +417,11 @@ static int ubifs_show_options(struct seq_file *s, struct vfsmount *mnt)
 	else if (c->mount_opts.chk_data_crc == 1)
 		seq_printf(s, ",no_chk_data_crc");
 
+	if (c->mount_opts.override_compr) {
+		seq_printf(s, ",compr=");
+		seq_printf(s, ubifs_compr_name(c->mount_opts.compr_type));
+	}
+
 	return 0;
 }
 
@@ -878,6 +883,7 @@ static int check_volume_empty(struct ubifs_info *c)
  * Opt_no_bulk_read: disable bulk-reads
  * Opt_chk_data_crc: check CRCs when reading data nodes
  * Opt_no_chk_data_crc: do not check CRCs when reading data nodes
+ * Opt_override_compr: override default compressor
  * Opt_err: just end of array marker
  */
 enum {
@@ -887,6 +893,7 @@ enum {
 	Opt_no_bulk_read,
 	Opt_chk_data_crc,
 	Opt_no_chk_data_crc,
+	Opt_override_compr,
 	Opt_err,
 };
 
@@ -897,6 +904,7 @@ static const match_table_t tokens = {
 	{Opt_no_bulk_read, "no_bulk_read"},
 	{Opt_chk_data_crc, "chk_data_crc"},
 	{Opt_no_chk_data_crc, "no_chk_data_crc"},
+	{Opt_override_compr, "compr=%s"},
 	{Opt_err, NULL},
 };
 
@@ -950,6 +958,28 @@ static int ubifs_parse_options(struct ubifs_info *c, char *options,
 			c->mount_opts.chk_data_crc = 1;
 			c->no_chk_data_crc = 1;
 			break;
+		case Opt_override_compr:
+		{
+			char *name = match_strdup(&args[0]);
+
+			if (!name)
+				return -ENOMEM;
+			if (!strcmp(name, "none"))
+				c->mount_opts.compr_type = UBIFS_COMPR_NONE;
+			else if (!strcmp(name, "lzo"))
+				c->mount_opts.compr_type = UBIFS_COMPR_LZO;
+			else if (!strcmp(name, "zlib"))
+				c->mount_opts.compr_type = UBIFS_COMPR_ZLIB;
+			else {
+				ubifs_err("unknown compressor \"%s\"", name);
+				kfree(name);
+				return -EINVAL;
+			}
+			kfree(name);
+			c->mount_opts.override_compr = 1;
+			c->default_compr = c->mount_opts.compr_type;
+			break;
+		}
 		default:
 			ubifs_err("unrecognized mount option \"%s\" "
 				  "or missing value", p);
@@ -1100,13 +1130,13 @@ static int mount_ubifs(struct ubifs_info *c)
 		goto out_free;
 
 	/*
-	 * Make sure the compressor which is set as the default on in the
-	 * superblock was actually compiled in.
+	 * Make sure the compressor which is set as default in the superblock
+	 * or overriden by mount options is actually compiled in.
 	 */
 	if (!ubifs_compr_present(c->default_compr)) {
-		ubifs_warn("'%s' compressor is set by superblock, but not "
-			   "compiled in", ubifs_compr_name(c->default_compr));
-		c->default_compr = UBIFS_COMPR_NONE;
+		ubifs_err("'compressor \"%s\" is not compiled in",
+			  ubifs_compr_name(c->default_compr));
+		goto out_free;
 	}
 
 	dbg_failure_mode_registration(c);
@@ -2023,8 +2053,8 @@ static int __init ubifs_init(void)
 	/*
 	 * We use 2 bit wide bit-fields to store compression type, which should
 	 * be amended if more compressors are added. The bit-fields are:
-	 * @compr_type in 'struct ubifs_inode' and @default_compr in
-	 * 'struct ubifs_info'.
+	 * @compr_type in 'struct ubifs_inode', @default_compr in
+	 * 'struct ubifs_info' and @compr_type in 'struct ubifs_mount_opts'.
 	 */
 	BUILD_BUG_ON(UBIFS_COMPR_TYPES_CNT > 4);
 
diff --git a/fs/ubifs/ubifs.h b/fs/ubifs/ubifs.h
index 4d76aba57ee1..16840e099eff 100644
--- a/fs/ubifs/ubifs.h
+++ b/fs/ubifs/ubifs.h
@@ -893,13 +893,21 @@ struct ubifs_orphan {
 /**
  * struct ubifs_mount_opts - UBIFS-specific mount options information.
  * @unmount_mode: selected unmount mode (%0 default, %1 normal, %2 fast)
- * @bulk_read: enable bulk-reads
- * @chk_data_crc: check CRCs when reading data nodes
+ * @bulk_read: enable/disable bulk-reads (%0 default, %1 disabe, %2 enable)
+ * @chk_data_crc: enable/disable CRC data checking when reading data nodes
+ *                (%0 default, %1 disabe, %2 enable)
+ * @override_compr: override default compressor (%0 - do not override and use
+ *                  superblock compressor, %1 - override and use compressor
+ *                  specified in @compr_type)
+ * @compr_type: compressor type to override the superblock compressor with
+ *              (%UBIFS_COMPR_NONE, etc)
  */
 struct ubifs_mount_opts {
 	unsigned int unmount_mode:2;
 	unsigned int bulk_read:2;
 	unsigned int chk_data_crc:2;
+	unsigned int override_compr:1;
+	unsigned int compr_type:2;
 };
 
 /**
-- 
cgit v1.2.3


From 5dd7cbc083f3a91fa7454125fe992826701b67bc Mon Sep 17 00:00:00 2001
From: Kukkonen Mika <mika.kukkonen@nokia.com>
Date: Tue, 2 Dec 2008 11:32:49 +0200
Subject: UBIFS: avoid unnecessary checks

I have a habit of compiling kernel with
EXTRA_CFLAGS="-Wextra -Wno-unused -Wno-sign-compare -Wno-missing-field-initializers"
and so fs/ubifs/key.h give lots (~10) of these every time:

CC      fs/ubifs/tnc_misc.o
In file included from fs/ubifs/ubifs.h:1725,
from fs/ubifs/tnc_misc.c:30:
fs/ubifs/key.h: In function 'key_r5_hash':
fs/ubifs/key.h:64: warning: comparison of unsigned expression >= 0 is always true
fs/ubifs/key.h: In function 'key_test_hash':
fs/ubifs/key.h:81: warning: comparison of unsigned expression >= 0 is always true

This patch fixes the warnings.

Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
---
 fs/ubifs/key.h | 32 ++++++++++++++++++--------------
 1 file changed, 18 insertions(+), 14 deletions(-)

diff --git a/fs/ubifs/key.h b/fs/ubifs/key.h
index 3f1f16bc25c9..efb3430a2581 100644
--- a/fs/ubifs/key.h
+++ b/fs/ubifs/key.h
@@ -37,6 +37,22 @@
 #ifndef __UBIFS_KEY_H__
 #define __UBIFS_KEY_H__
 
+/**
+ * key_mask_hash - mask a valid hash value.
+ * @val: value to be masked
+ *
+ * We use hash values as offset in directories, so values %0 and %1 are
+ * reserved for "." and "..". %2 is reserved for "end of readdir" marker. This
+ * function makes sure the reserved values are not used.
+ */
+static inline uint32_t key_mask_hash(uint32_t hash)
+{
+	hash &= UBIFS_S_KEY_HASH_MASK;
+	if (unlikely(hash <= 2))
+		hash += 3;
+	return hash;
+}
+
 /**
  * key_r5_hash - R5 hash function (borrowed from reiserfs).
  * @s: direntry name
@@ -54,16 +70,7 @@ static inline uint32_t key_r5_hash(const char *s, int len)
 		str++;
 	}
 
-	a &= UBIFS_S_KEY_HASH_MASK;
-
-	/*
-	 * We use hash values as offset in directories, so values %0 and %1 are
-	 * reserved for "." and "..". %2 is reserved for "end of readdir"
-	 * marker.
-	 */
-	if (unlikely(a >= 0 && a <= 2))
-		a += 3;
-	return a;
+	return key_mask_hash(a);
 }
 
 /**
@@ -77,10 +84,7 @@ static inline uint32_t key_test_hash(const char *str, int len)
 
 	len = min_t(uint32_t, len, 4);
 	memcpy(&a, str, len);
-	a &= UBIFS_S_KEY_HASH_MASK;
-	if (unlikely(a >= 0 && a <= 2))
-		a += 3;
-	return a;
+	return key_mask_hash(a);
 }
 
 /**
-- 
cgit v1.2.3


From 17c2f9f85c896b48a5d74a9155d99ec5b241a0e6 Mon Sep 17 00:00:00 2001
From: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Date: Fri, 17 Oct 2008 13:31:39 +0300
Subject: UBIFS: separate debugging fields out

Introduce a new data structure which contains all debugging
stuff inside. This is cleaner than having debugging stuff
directly in 'c'.

Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
---
 fs/ubifs/commit.c     | 25 +++++++++---------
 fs/ubifs/debug.c      | 71 +++++++++++++++++++++++++++++++++++++++------------
 fs/ubifs/debug.h      | 51 ++++++++++++++++++++++++++++++------
 fs/ubifs/lprops.c     |  2 +-
 fs/ubifs/lpt_commit.c | 55 +++++++++++++++++++--------------------
 fs/ubifs/orphan.c     |  2 +-
 fs/ubifs/super.c      | 22 +++++-----------
 fs/ubifs/tnc_commit.c |  7 ++---
 fs/ubifs/ubifs.h      | 34 +++---------------------
 9 files changed, 156 insertions(+), 113 deletions(-)

diff --git a/fs/ubifs/commit.c b/fs/ubifs/commit.c
index b49884c8c10e..f3a7945527fb 100644
--- a/fs/ubifs/commit.c
+++ b/fs/ubifs/commit.c
@@ -470,12 +470,12 @@ int dbg_old_index_check_init(struct ubifs_info *c, struct ubifs_zbranch *zroot)
 {
 	struct ubifs_idx_node *idx;
 	int lnum, offs, len, err = 0;
+	struct ubifs_debug_info *d = c->dbg;
 
-	c->old_zroot = *zroot;
-
-	lnum = c->old_zroot.lnum;
-	offs = c->old_zroot.offs;
-	len = c->old_zroot.len;
+	d->old_zroot = *zroot;
+	lnum = d->old_zroot.lnum;
+	offs = d->old_zroot.offs;
+	len = d->old_zroot.len;
 
 	idx = kmalloc(c->max_idx_node_sz, GFP_NOFS);
 	if (!idx)
@@ -485,8 +485,8 @@ int dbg_old_index_check_init(struct ubifs_info *c, struct ubifs_zbranch *zroot)
 	if (err)
 		goto out;
 
-	c->old_zroot_level = le16_to_cpu(idx->level);
-	c->old_zroot_sqnum = le64_to_cpu(idx->ch.sqnum);
+	d->old_zroot_level = le16_to_cpu(idx->level);
+	d->old_zroot_sqnum = le64_to_cpu(idx->ch.sqnum);
 out:
 	kfree(idx);
 	return err;
@@ -509,6 +509,7 @@ int dbg_check_old_index(struct ubifs_info *c, struct ubifs_zbranch *zroot)
 {
 	int lnum, offs, len, err = 0, uninitialized_var(last_level), child_cnt;
 	int first = 1, iip;
+	struct ubifs_debug_info *d = c->dbg;
 	union ubifs_key lower_key, upper_key, l_key, u_key;
 	unsigned long long uninitialized_var(last_sqnum);
 	struct ubifs_idx_node *idx;
@@ -525,9 +526,9 @@ int dbg_check_old_index(struct ubifs_info *c, struct ubifs_zbranch *zroot)
 	     UBIFS_IDX_NODE_SZ;
 
 	/* Start at the old zroot */
-	lnum = c->old_zroot.lnum;
-	offs = c->old_zroot.offs;
-	len = c->old_zroot.len;
+	lnum = d->old_zroot.lnum;
+	offs = d->old_zroot.offs;
+	len = d->old_zroot.len;
 	iip = 0;
 
 	/*
@@ -560,11 +561,11 @@ int dbg_check_old_index(struct ubifs_info *c, struct ubifs_zbranch *zroot)
 		if (first) {
 			first = 0;
 			/* Check root level and sqnum */
-			if (le16_to_cpu(idx->level) != c->old_zroot_level) {
+			if (le16_to_cpu(idx->level) != d->old_zroot_level) {
 				err = 2;
 				goto out_dump;
 			}
-			if (le64_to_cpu(idx->ch.sqnum) != c->old_zroot_sqnum) {
+			if (le64_to_cpu(idx->ch.sqnum) != d->old_zroot_sqnum) {
 				err = 3;
 				goto out_dump;
 			}
diff --git a/fs/ubifs/debug.c b/fs/ubifs/debug.c
index 510ffa0bbda4..0332a856a082 100644
--- a/fs/ubifs/debug.c
+++ b/fs/ubifs/debug.c
@@ -705,7 +705,7 @@ void dbg_dump_leb(const struct ubifs_info *c, int lnum)
 
 	printk(KERN_DEBUG "(pid %d) Dumping LEB %d\n", current->pid, lnum);
 
-	sleb = ubifs_scan(c, lnum, 0, c->dbg_buf);
+	sleb = ubifs_scan(c, lnum, 0, c->dbg->buf);
 	if (IS_ERR(sleb)) {
 		ubifs_err("scan error %d", (int)PTR_ERR(sleb));
 		return;
@@ -2097,7 +2097,7 @@ static int simple_rand(void)
 	return (next >> 16) & 32767;
 }
 
-void dbg_failure_mode_registration(struct ubifs_info *c)
+static void failure_mode_init(struct ubifs_info *c)
 {
 	struct failure_mode_info *fmi;
 
@@ -2112,7 +2112,7 @@ void dbg_failure_mode_registration(struct ubifs_info *c)
 	spin_unlock(&fmi_lock);
 }
 
-void dbg_failure_mode_deregistration(struct ubifs_info *c)
+static void failure_mode_exit(struct ubifs_info *c)
 {
 	struct failure_mode_info *fmi, *tmp;
 
@@ -2146,42 +2146,44 @@ static int in_failure_mode(struct ubi_volume_desc *desc)
 	struct ubifs_info *c = dbg_find_info(desc);
 
 	if (c && dbg_failure_mode)
-		return c->failure_mode;
+		return c->dbg->failure_mode;
 	return 0;
 }
 
 static int do_fail(struct ubi_volume_desc *desc, int lnum, int write)
 {
 	struct ubifs_info *c = dbg_find_info(desc);
+	struct ubifs_debug_info *d;
 
 	if (!c || !dbg_failure_mode)
 		return 0;
-	if (c->failure_mode)
+	d = c->dbg;
+	if (d->failure_mode)
 		return 1;
-	if (!c->fail_cnt) {
+	if (!d->fail_cnt) {
 		/* First call - decide delay to failure */
 		if (chance(1, 2)) {
 			unsigned int delay = 1 << (simple_rand() >> 11);
 
 			if (chance(1, 2)) {
-				c->fail_delay = 1;
-				c->fail_timeout = jiffies +
+				d->fail_delay = 1;
+				d->fail_timeout = jiffies +
 						  msecs_to_jiffies(delay);
 				dbg_rcvry("failing after %ums", delay);
 			} else {
-				c->fail_delay = 2;
-				c->fail_cnt_max = delay;
+				d->fail_delay = 2;
+				d->fail_cnt_max = delay;
 				dbg_rcvry("failing after %u calls", delay);
 			}
 		}
-		c->fail_cnt += 1;
+		d->fail_cnt += 1;
 	}
 	/* Determine if failure delay has expired */
-	if (c->fail_delay == 1) {
-		if (time_before(jiffies, c->fail_timeout))
+	if (d->fail_delay == 1) {
+		if (time_before(jiffies, d->fail_timeout))
 			return 0;
-	} else if (c->fail_delay == 2)
-		if (c->fail_cnt++ < c->fail_cnt_max)
+	} else if (d->fail_delay == 2)
+		if (d->fail_cnt++ < d->fail_cnt_max)
 			return 0;
 	if (lnum == UBIFS_SB_LNUM) {
 		if (write) {
@@ -2239,7 +2241,7 @@ static int do_fail(struct ubi_volume_desc *desc, int lnum, int write)
 		dbg_rcvry("failing in bud LEB %d commit not running", lnum);
 	}
 	ubifs_err("*** SETTING FAILURE MODE ON (LEB %d) ***", lnum);
-	c->failure_mode = 1;
+	d->failure_mode = 1;
 	dump_stack();
 	return 1;
 }
@@ -2344,4 +2346,41 @@ int dbg_leb_map(struct ubi_volume_desc *desc, int lnum, int dtype)
 	return 0;
 }
 
+/**
+ * ubifs_debugging_init - initialize UBIFS debugging.
+ * @c: UBIFS file-system description object
+ *
+ * This function initializes debugging-related data for the file system.
+ * Returns zero in case of success and a negative error code in case of
+ * failure.
+ */
+int ubifs_debugging_init(struct ubifs_info *c)
+{
+	c->dbg = kzalloc(sizeof(struct ubifs_debug_info), GFP_KERNEL);
+	if (!c->dbg)
+		return -ENOMEM;
+
+	c->dbg->buf = vmalloc(c->leb_size);
+	if (!c->dbg->buf)
+		goto out;
+
+	failure_mode_init(c);
+	return 0;
+
+out:
+	kfree(c->dbg);
+	return -ENOMEM;
+}
+
+/**
+ * ubifs_debugging_exit - free debugging data.
+ * @c: UBIFS file-system description object
+ */
+void ubifs_debugging_exit(struct ubifs_info *c)
+{
+	failure_mode_exit(c);
+	vfree(c->dbg->buf);
+	kfree(c->dbg);
+}
+
 #endif /* CONFIG_UBIFS_FS_DEBUG */
diff --git a/fs/ubifs/debug.h b/fs/ubifs/debug.h
index 33d6b95071e4..d6ea1362d56a 100644
--- a/fs/ubifs/debug.h
+++ b/fs/ubifs/debug.h
@@ -25,7 +25,43 @@
 
 #ifdef CONFIG_UBIFS_FS_DEBUG
 
-#define UBIFS_DBG(op) op
+/**
+ * ubifs_debug_info - per-FS debugging information.
+ * @buf: a buffer of LEB size, used for various purposes
+ * @old_zroot: old index root - used by 'dbg_check_old_index()'
+ * @old_zroot_level: old index root level - used by 'dbg_check_old_index()'
+ * @old_zroot_sqnum: old index root sqnum - used by 'dbg_check_old_index()'
+ * @failure_mode: failure mode for recovery testing
+ * @fail_delay: 0=>don't delay, 1=>delay a time, 2=>delay a number of calls
+ * @fail_timeout: time in jiffies when delay of failure mode expires
+ * @fail_cnt: current number of calls to failure mode I/O functions
+ * @fail_cnt_max: number of calls by which to delay failure mode
+ * @chk_lpt_sz: used by LPT tree size checker
+ * @chk_lpt_sz2: used by LPT tree size checker
+ * @chk_lpt_wastage: used by LPT tree size checker
+ * @chk_lpt_lebs: used by LPT tree size checker
+ * @new_nhead_offs: used by LPT tree size checker
+ * @new_ihead_lnum: used by debugging to check ihead_lnum
+ * @new_ihead_offs: used by debugging to check ihead_offs
+ */
+struct ubifs_debug_info {
+	void *buf;
+	struct ubifs_zbranch old_zroot;
+	int old_zroot_level;
+	unsigned long long old_zroot_sqnum;
+	int failure_mode;
+	int fail_delay;
+	unsigned long fail_timeout;
+	unsigned int fail_cnt;
+	unsigned int fail_cnt_max;
+	long long chk_lpt_sz;
+	long long chk_lpt_sz2;
+	long long chk_lpt_wastage;
+	int chk_lpt_lebs;
+	int new_nhead_offs;
+	int new_ihead_lnum;
+	int new_ihead_offs;
+};
 
 #define ubifs_assert(expr) do {                                                \
 	if (unlikely(!(expr))) {                                               \
@@ -211,6 +247,9 @@ extern unsigned int ubifs_msg_flags;
 extern unsigned int ubifs_chk_flags;
 extern unsigned int ubifs_tst_flags;
 
+int ubifs_debugging_init(struct ubifs_info *c);
+void ubifs_debugging_exit(struct ubifs_info *c);
+
 /* Dump functions */
 
 const char *dbg_ntype(int type);
@@ -274,9 +313,6 @@ int dbg_force_in_the_gaps(void);
 
 #define dbg_failure_mode (ubifs_tst_flags & UBIFS_TST_RCVRY)
 
-void dbg_failure_mode_registration(struct ubifs_info *c);
-void dbg_failure_mode_deregistration(struct ubifs_info *c);
-
 #ifndef UBIFS_DBG_PRESERVE_UBI
 
 #define ubi_leb_read   dbg_leb_read
@@ -320,8 +356,6 @@ static inline int dbg_change(struct ubi_volume_desc *desc, int lnum,
 
 #else /* !CONFIG_UBIFS_FS_DEBUG */
 
-#define UBIFS_DBG(op)
-
 /* Use "if (0)" to make compiler check arguments even if debugging is off */
 #define ubifs_assert(expr)  do {                                               \
 	if (0 && (expr))                                                       \
@@ -360,6 +394,9 @@ static inline int dbg_change(struct ubi_volume_desc *desc, int lnum,
 #define DBGKEY(key)  ((char *)(key))
 #define DBGKEY1(key) ((char *)(key))
 
+#define ubifs_debugging_init(c)               0
+#define ubifs_debugging_exit(c)               ({})
+
 #define dbg_ntype(type)                       ""
 #define dbg_cstate(cmt_state)                 ""
 #define dbg_get_key_dump(c, key)              ({})
@@ -396,8 +433,6 @@ static inline int dbg_change(struct ubi_volume_desc *desc, int lnum,
 #define dbg_force_in_the_gaps_enabled              0
 #define dbg_force_in_the_gaps()                    0
 #define dbg_failure_mode                           0
-#define dbg_failure_mode_registration(c)           ({})
-#define dbg_failure_mode_deregistration(c)         ({})
 
 #endif /* !CONFIG_UBIFS_FS_DEBUG */
 
diff --git a/fs/ubifs/lprops.c b/fs/ubifs/lprops.c
index f27176e9b70d..10ba663eb329 100644
--- a/fs/ubifs/lprops.c
+++ b/fs/ubifs/lprops.c
@@ -1088,7 +1088,7 @@ static int scan_check_cb(struct ubifs_info *c,
 		}
 	}
 
-	sleb = ubifs_scan(c, lnum, 0, c->dbg_buf);
+	sleb = ubifs_scan(c, lnum, 0, c->dbg->buf);
 	if (IS_ERR(sleb)) {
 		/*
 		 * After an unclean unmount, empty and freeable LEBs
diff --git a/fs/ubifs/lpt_commit.c b/fs/ubifs/lpt_commit.c
index a41434b42785..1aefab9f0b5e 100644
--- a/fs/ubifs/lpt_commit.c
+++ b/fs/ubifs/lpt_commit.c
@@ -1602,7 +1602,7 @@ static int dbg_check_ltab_lnum(struct ubifs_info *c, int lnum)
 {
 	int err, len = c->leb_size, dirty = 0, node_type, node_num, node_len;
 	int ret;
-	void *buf = c->dbg_buf;
+	void *buf = c->dbg->buf;
 
 	dbg_lp("LEB %d", lnum);
 	err = ubi_read(c->ubi, lnum, buf, 0, c->leb_size);
@@ -1731,15 +1731,16 @@ int dbg_chk_lpt_free_spc(struct ubifs_info *c)
  */
 int dbg_chk_lpt_sz(struct ubifs_info *c, int action, int len)
 {
+	struct ubifs_debug_info *d = c->dbg;
 	long long chk_lpt_sz, lpt_sz;
 	int err = 0;
 
 	switch (action) {
 	case 0:
-		c->chk_lpt_sz = 0;
-		c->chk_lpt_sz2 = 0;
-		c->chk_lpt_lebs = 0;
-		c->chk_lpt_wastage = 0;
+		d->chk_lpt_sz = 0;
+		d->chk_lpt_sz2 = 0;
+		d->chk_lpt_lebs = 0;
+		d->chk_lpt_wastage = 0;
 		if (c->dirty_pn_cnt > c->pnode_cnt) {
 			dbg_err("dirty pnodes %d exceed max %d",
 				c->dirty_pn_cnt, c->pnode_cnt);
@@ -1752,35 +1753,35 @@ int dbg_chk_lpt_sz(struct ubifs_info *c, int action, int len)
 		}
 		return err;
 	case 1:
-		c->chk_lpt_sz += len;
+		d->chk_lpt_sz += len;
 		return 0;
 	case 2:
-		c->chk_lpt_sz += len;
-		c->chk_lpt_wastage += len;
-		c->chk_lpt_lebs += 1;
+		d->chk_lpt_sz += len;
+		d->chk_lpt_wastage += len;
+		d->chk_lpt_lebs += 1;
 		return 0;
 	case 3:
 		chk_lpt_sz = c->leb_size;
-		chk_lpt_sz *= c->chk_lpt_lebs;
+		chk_lpt_sz *= d->chk_lpt_lebs;
 		chk_lpt_sz += len - c->nhead_offs;
-		if (c->chk_lpt_sz != chk_lpt_sz) {
+		if (d->chk_lpt_sz != chk_lpt_sz) {
 			dbg_err("LPT wrote %lld but space used was %lld",
-				c->chk_lpt_sz, chk_lpt_sz);
+				d->chk_lpt_sz, chk_lpt_sz);
 			err = -EINVAL;
 		}
-		if (c->chk_lpt_sz > c->lpt_sz) {
+		if (d->chk_lpt_sz > c->lpt_sz) {
 			dbg_err("LPT wrote %lld but lpt_sz is %lld",
-				c->chk_lpt_sz, c->lpt_sz);
+				d->chk_lpt_sz, c->lpt_sz);
 			err = -EINVAL;
 		}
-		if (c->chk_lpt_sz2 && c->chk_lpt_sz != c->chk_lpt_sz2) {
+		if (d->chk_lpt_sz2 && d->chk_lpt_sz != d->chk_lpt_sz2) {
 			dbg_err("LPT layout size %lld but wrote %lld",
-				c->chk_lpt_sz, c->chk_lpt_sz2);
+				d->chk_lpt_sz, d->chk_lpt_sz2);
 			err = -EINVAL;
 		}
-		if (c->chk_lpt_sz2 && c->new_nhead_offs != len) {
+		if (d->chk_lpt_sz2 && d->new_nhead_offs != len) {
 			dbg_err("LPT new nhead offs: expected %d was %d",
-				c->new_nhead_offs, len);
+				d->new_nhead_offs, len);
 			err = -EINVAL;
 		}
 		lpt_sz = (long long)c->pnode_cnt * c->pnode_sz;
@@ -1788,22 +1789,22 @@ int dbg_chk_lpt_sz(struct ubifs_info *c, int action, int len)
 		lpt_sz += c->ltab_sz;
 		if (c->big_lpt)
 			lpt_sz += c->lsave_sz;
-		if (c->chk_lpt_sz - c->chk_lpt_wastage > lpt_sz) {
+		if (d->chk_lpt_sz - d->chk_lpt_wastage > lpt_sz) {
 			dbg_err("LPT chk_lpt_sz %lld + waste %lld exceeds %lld",
-				c->chk_lpt_sz, c->chk_lpt_wastage, lpt_sz);
+				d->chk_lpt_sz, d->chk_lpt_wastage, lpt_sz);
 			err = -EINVAL;
 		}
 		if (err)
 			dbg_dump_lpt_info(c);
-		c->chk_lpt_sz2 = c->chk_lpt_sz;
-		c->chk_lpt_sz = 0;
-		c->chk_lpt_wastage = 0;
-		c->chk_lpt_lebs = 0;
-		c->new_nhead_offs = len;
+		d->chk_lpt_sz2 = d->chk_lpt_sz;
+		d->chk_lpt_sz = 0;
+		d->chk_lpt_wastage = 0;
+		d->chk_lpt_lebs = 0;
+		d->new_nhead_offs = len;
 		return err;
 	case 4:
-		c->chk_lpt_sz += len;
-		c->chk_lpt_wastage += len;
+		d->chk_lpt_sz += len;
+		d->chk_lpt_wastage += len;
 		return 0;
 	default:
 		return -EINVAL;
diff --git a/fs/ubifs/orphan.c b/fs/ubifs/orphan.c
index 9bd5a43d4526..9e6f403f170e 100644
--- a/fs/ubifs/orphan.c
+++ b/fs/ubifs/orphan.c
@@ -899,7 +899,7 @@ static int dbg_scan_orphans(struct ubifs_info *c, struct check_info *ci)
 	for (lnum = c->orph_first; lnum <= c->orph_last; lnum++) {
 		struct ubifs_scan_leb *sleb;
 
-		sleb = ubifs_scan(c, lnum, 0, c->dbg_buf);
+		sleb = ubifs_scan(c, lnum, 0, c->dbg->buf);
 		if (IS_ERR(sleb)) {
 			err = PTR_ERR(sleb);
 			break;
diff --git a/fs/ubifs/super.c b/fs/ubifs/super.c
index fc81022cc26d..ad44822059c7 100644
--- a/fs/ubifs/super.c
+++ b/fs/ubifs/super.c
@@ -1069,11 +1069,9 @@ static int mount_ubifs(struct ubifs_info *c)
 	if (err)
 		return err;
 
-#ifdef CONFIG_UBIFS_FS_DEBUG
-	c->dbg_buf = vmalloc(c->leb_size);
-	if (!c->dbg_buf)
-		return -ENOMEM;
-#endif
+	err = ubifs_debugging_init(c);
+	if (err)
+		return err;
 
 	err = check_volume_empty(c);
 	if (err)
@@ -1139,18 +1137,16 @@ static int mount_ubifs(struct ubifs_info *c)
 		goto out_free;
 	}
 
-	dbg_failure_mode_registration(c);
-
 	err = init_constants_late(c);
 	if (err)
-		goto out_dereg;
+		goto out_free;
 
 	sz = ALIGN(c->max_idx_node_sz, c->min_io_size);
 	sz = ALIGN(sz + c->max_idx_node_sz, c->min_io_size);
 	c->cbuf = kmalloc(sz, GFP_NOFS);
 	if (!c->cbuf) {
 		err = -ENOMEM;
-		goto out_dereg;
+		goto out_free;
 	}
 
 	sprintf(c->bgt_name, BGT_NAME_PATTERN, c->vi.ubi_num, c->vi.vol_id);
@@ -1350,14 +1346,12 @@ out_wbufs:
 	free_wbufs(c);
 out_cbuf:
 	kfree(c->cbuf);
-out_dereg:
-	dbg_failure_mode_deregistration(c);
 out_free:
 	kfree(c->bu.buf);
 	vfree(c->ileb_buf);
 	vfree(c->sbuf);
 	kfree(c->bottom_up_buf);
-	UBIFS_DBG(vfree(c->dbg_buf));
+	ubifs_debugging_exit(c);
 	return err;
 }
 
@@ -1394,8 +1388,7 @@ static void ubifs_umount(struct ubifs_info *c)
 	vfree(c->ileb_buf);
 	vfree(c->sbuf);
 	kfree(c->bottom_up_buf);
-	UBIFS_DBG(vfree(c->dbg_buf));
-	dbg_failure_mode_deregistration(c);
+	ubifs_debugging_exit(c);
 }
 
 /**
@@ -1879,7 +1872,6 @@ static int ubifs_fill_super(struct super_block *sb, void *data, int silent)
 		goto out_iput;
 
 	mutex_unlock(&c->umount_mutex);
-
 	return 0;
 
 out_iput:
diff --git a/fs/ubifs/tnc_commit.c b/fs/ubifs/tnc_commit.c
index 8ac76b1c2d55..3c0af452887b 100644
--- a/fs/ubifs/tnc_commit.c
+++ b/fs/ubifs/tnc_commit.c
@@ -553,8 +553,8 @@ static int layout_in_empty_space(struct ubifs_info *c)
 	}
 
 #ifdef CONFIG_UBIFS_FS_DEBUG
-	c->new_ihead_lnum = lnum;
-	c->new_ihead_offs = buf_offs;
+	c->dbg->new_ihead_lnum = lnum;
+	c->dbg->new_ihead_offs = buf_offs;
 #endif
 
 	return 0;
@@ -1002,7 +1002,8 @@ static int write_index(struct ubifs_info *c)
 	}
 
 #ifdef CONFIG_UBIFS_FS_DEBUG
-	if (lnum != c->new_ihead_lnum || buf_offs != c->new_ihead_offs) {
+	if (lnum != c->dbg->new_ihead_lnum ||
+	    buf_offs != c->dbg->new_ihead_offs) {
 		ubifs_err("inconsistent ihead");
 		return -EINVAL;
 	}
diff --git a/fs/ubifs/ubifs.h b/fs/ubifs/ubifs.h
index 16840e099eff..7e090a5e2bf6 100644
--- a/fs/ubifs/ubifs.h
+++ b/fs/ubifs/ubifs.h
@@ -910,6 +910,8 @@ struct ubifs_mount_opts {
 	unsigned int compr_type:2;
 };
 
+struct ubifs_debug_info;
+
 /**
  * struct ubifs_info - UBIFS file-system description data structure
  * (per-superblock).
@@ -972,8 +974,6 @@ struct ubifs_mount_opts {
  * @ileb_nxt: next pre-allocated index LEBs
  * @old_idx: tree of index nodes obsoleted since the last commit start
  * @bottom_up_buf: a buffer which is used by 'dirty_cow_bottom_up()' in tnc.c
- * @new_ihead_lnum: used by debugging to check ihead_lnum
- * @new_ihead_offs: used by debugging to check ihead_offs
  *
  * @mst_node: master node
  * @mst_offs: offset of valid master node
@@ -1157,15 +1157,7 @@ struct ubifs_mount_opts {
  * @always_chk_crc: always check CRCs (while mounting and remounting rw)
  * @mount_opts: UBIFS-specific mount options
  *
- * @dbg_buf: a buffer of LEB size used for debugging purposes
- * @old_zroot: old index root - used by 'dbg_check_old_index()'
- * @old_zroot_level: old index root level - used by 'dbg_check_old_index()'
- * @old_zroot_sqnum: old index root sqnum - used by 'dbg_check_old_index()'
- * @failure_mode: failure mode for recovery testing
- * @fail_delay: 0=>don't delay, 1=>delay a time, 2=>delay a number of calls
- * @fail_timeout: time in jiffies when delay of failure mode expires
- * @fail_cnt: current number of calls to failure mode I/O functions
- * @fail_cnt_max: number of calls by which to delay failure mode
+ * @dbg: debugging-related information
  */
 struct ubifs_info {
 	struct super_block *vfs_sb;
@@ -1221,10 +1213,6 @@ struct ubifs_info {
 	int ileb_nxt;
 	struct rb_root old_idx;
 	int *bottom_up_buf;
-#ifdef CONFIG_UBIFS_FS_DEBUG
-	int new_ihead_lnum;
-	int new_ihead_offs;
-#endif
 
 	struct ubifs_mst_node *mst_node;
 	int mst_offs;
@@ -1399,21 +1387,7 @@ struct ubifs_info {
 	struct ubifs_mount_opts mount_opts;
 
 #ifdef CONFIG_UBIFS_FS_DEBUG
-	void *dbg_buf;
-	struct ubifs_zbranch old_zroot;
-	int old_zroot_level;
-	unsigned long long old_zroot_sqnum;
-	int failure_mode;
-	int fail_delay;
-	unsigned long fail_timeout;
-	unsigned int fail_cnt;
-	unsigned int fail_cnt_max;
-	long long chk_lpt_sz;
-	long long chk_lpt_sz2;
-	long long chk_lpt_wastage;
-	int chk_lpt_lebs;
-	int new_nhead_lnum;
-	int new_nhead_offs;
+	struct ubifs_debug_info *dbg;
 #endif
 };
 
-- 
cgit v1.2.3


From 552ff3179d1e93a3e982357544c059f3e9a5516e Mon Sep 17 00:00:00 2001
From: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Date: Thu, 23 Oct 2008 11:49:28 +0300
Subject: UBIFS: add debugfs support

We need to have a possibility to see various UBIFS variables
and ask UBIFS to dump various information. Debugfs is what
we need.

Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
---
 fs/ubifs/debug.c | 173 +++++++++++++++++++++++++++++++++++++++++++++++++------
 fs/ubifs/debug.h |  27 ++++++++-
 fs/ubifs/super.c |  12 ++++
 fs/ubifs/ubifs.h |   1 +
 4 files changed, 193 insertions(+), 20 deletions(-)

diff --git a/fs/ubifs/debug.c b/fs/ubifs/debug.c
index 0332a856a082..56842772c804 100644
--- a/fs/ubifs/debug.c
+++ b/fs/ubifs/debug.c
@@ -32,6 +32,7 @@
 #include "ubifs.h"
 #include <linux/module.h>
 #include <linux/moduleparam.h>
+#include <linux/debugfs.h>
 
 #ifdef CONFIG_UBIFS_FS_DEBUG
 
@@ -988,22 +989,20 @@ static int dbg_check_key_order(struct ubifs_info *c, struct ubifs_zbranch *zbr1,
 	err = 1;
 	key_read(c, &dent1->key, &key);
 	if (keys_cmp(c, &zbr1->key, &key)) {
-		dbg_err("1st entry at %d:%d has key %s", zbr1->lnum,
-			zbr1->offs, DBGKEY(&key));
-		dbg_err("but it should have key %s according to tnc",
-			DBGKEY(&zbr1->key));
-			dbg_dump_node(c, dent1);
-			goto out_free;
+		ubifs_err("1st entry at %d:%d has key %s", zbr1->lnum,
+			  zbr1->offs, DBGKEY(&key));
+		ubifs_err("but it should have key %s according to tnc",
+			  DBGKEY(&zbr1->key)); dbg_dump_node(c, dent1);
+		goto out_free;
 	}
 
 	key_read(c, &dent2->key, &key);
 	if (keys_cmp(c, &zbr2->key, &key)) {
-		dbg_err("2nd entry at %d:%d has key %s", zbr1->lnum,
-			zbr1->offs, DBGKEY(&key));
-		dbg_err("but it should have key %s according to tnc",
-			DBGKEY(&zbr2->key));
-			dbg_dump_node(c, dent2);
-			goto out_free;
+		ubifs_err("2nd entry at %d:%d has key %s", zbr1->lnum,
+			  zbr1->offs, DBGKEY(&key));
+		ubifs_err("but it should have key %s according to tnc",
+			  DBGKEY(&zbr2->key)); dbg_dump_node(c, dent2);
+		goto out_free;
 	}
 
 	nlen1 = le16_to_cpu(dent1->nlen);
@@ -1015,14 +1014,14 @@ static int dbg_check_key_order(struct ubifs_info *c, struct ubifs_zbranch *zbr1,
 		goto out_free;
 	}
 	if (cmp == 0 && nlen1 == nlen2)
-		dbg_err("2 xent/dent nodes with the same name");
+		ubifs_err("2 xent/dent nodes with the same name");
 	else
-		dbg_err("bad order of colliding key %s",
+		ubifs_err("bad order of colliding key %s",
 			DBGKEY(&key));
 
-	dbg_msg("first node at %d:%d\n", zbr1->lnum, zbr1->offs);
+	ubifs_msg("first node at %d:%d\n", zbr1->lnum, zbr1->offs);
 	dbg_dump_node(c, dent1);
-	dbg_msg("second node at %d:%d\n", zbr2->lnum, zbr2->offs);
+	ubifs_msg("second node at %d:%d\n", zbr2->lnum, zbr2->offs);
 	dbg_dump_node(c, dent2);
 
 out_free:
@@ -2103,7 +2102,7 @@ static void failure_mode_init(struct ubifs_info *c)
 
 	fmi = kmalloc(sizeof(struct failure_mode_info), GFP_NOFS);
 	if (!fmi) {
-		dbg_err("Failed to register failure mode - no memory");
+		ubifs_err("Failed to register failure mode - no memory");
 		return;
 	}
 	fmi->c = c;
@@ -2383,4 +2382,144 @@ void ubifs_debugging_exit(struct ubifs_info *c)
 	kfree(c->dbg);
 }
 
+/*
+ * Root directory for UBIFS stuff in debugfs. Contains sub-directories which
+ * contain the stuff specific to particular file-system mounts.
+ */
+static struct dentry *debugfs_rootdir;
+
+/**
+ * dbg_debugfs_init - initialize debugfs file-system.
+ *
+ * UBIFS uses debugfs file-system to expose various debugging knobs to
+ * user-space. This function creates "ubifs" directory in the debugfs
+ * file-system. Returns zero in case of success and a negative error code in
+ * case of failure.
+ */
+int dbg_debugfs_init(void)
+{
+	debugfs_rootdir = debugfs_create_dir("ubifs", NULL);
+	if (IS_ERR(debugfs_rootdir)) {
+		int err = PTR_ERR(debugfs_rootdir);
+		ubifs_err("cannot create \"ubifs\" debugfs directory, "
+			  "error %d\n", err);
+		return err;
+	}
+
+	return 0;
+}
+
+/**
+ * dbg_debugfs_exit - remove the "ubifs" directory from debugfs file-system.
+ */
+void dbg_debugfs_exit(void)
+{
+	debugfs_remove(debugfs_rootdir);
+}
+
+static int open_debugfs_file(struct inode *inode, struct file *file)
+{
+	file->private_data = inode->i_private;
+	return 0;
+}
+
+static ssize_t write_debugfs_file(struct file *file, const char __user *buf,
+				  size_t count, loff_t *ppos)
+{
+	struct ubifs_info *c = file->private_data;
+	struct ubifs_debug_info *d = c->dbg;
+
+	if (file->f_path.dentry == d->dump_lprops)
+		dbg_dump_lprops(c);
+	else if (file->f_path.dentry == d->dump_budg) {
+		spin_lock(&c->space_lock);
+		dbg_dump_budg(c);
+		spin_unlock(&c->space_lock);
+	} else if (file->f_path.dentry == d->dump_budg) {
+		mutex_lock(&c->tnc_mutex);
+		dbg_dump_tnc(c);
+		mutex_unlock(&c->tnc_mutex);
+	} else
+		return -EINVAL;
+
+	*ppos += count;
+	return count;
+}
+
+static const struct file_operations debugfs_fops = {
+	.open = open_debugfs_file,
+	.write = write_debugfs_file,
+	.owner = THIS_MODULE,
+};
+
+/**
+ * dbg_debugfs_init_fs - initialize debugfs for UBIFS instance.
+ * @c: UBIFS file-system description object
+ *
+ * This function creates all debugfs files for this instance of UBIFS. Returns
+ * zero in case of success and a negative error code in case of failure.
+ *
+ * Note, the only reason we have not merged this function with the
+ * 'ubifs_debugging_init()' function is because it is better to initialize
+ * debugfs interfaces at the very end of the mount process, and remove them at
+ * the very beginning of the mount process.
+ */
+int dbg_debugfs_init_fs(struct ubifs_info *c)
+{
+	int err;
+	const char *fname;
+	struct dentry *dent;
+	struct ubifs_debug_info *d = c->dbg;
+
+	sprintf(d->debugfs_dir_name, "ubi%d_%d", c->vi.ubi_num, c->vi.vol_id);
+	d->debugfs_dir = debugfs_create_dir(d->debugfs_dir_name,
+					      debugfs_rootdir);
+	if (IS_ERR(d->debugfs_dir)) {
+		err = PTR_ERR(d->debugfs_dir);
+		ubifs_err("cannot create \"%s\" debugfs directory, error %d\n",
+			  d->debugfs_dir_name, err);
+		goto out;
+	}
+
+	fname = "dump_lprops";
+	dent = debugfs_create_file(fname, S_IWUGO, d->debugfs_dir, c,
+				   &debugfs_fops);
+	if (IS_ERR(dent))
+		goto out_remove;
+	d->dump_lprops = dent;
+
+	fname = "dump_budg";
+	dent = debugfs_create_file(fname, S_IWUGO, d->debugfs_dir, c,
+				   &debugfs_fops);
+	if (IS_ERR(dent))
+		goto out_remove;
+	d->dump_budg = dent;
+
+	fname = "dump_tnc";
+	dent = debugfs_create_file(fname, S_IWUGO, d->debugfs_dir, c,
+				   &debugfs_fops);
+	if (IS_ERR(dent))
+		goto out_remove;
+	d->dump_tnc = dent;
+
+	return 0;
+
+out_remove:
+	err = PTR_ERR(dent);
+	ubifs_err("cannot create \"%s\" debugfs directory, error %d\n",
+		  fname, err);
+	debugfs_remove_recursive(d->debugfs_dir);
+out:
+	return err;
+}
+
+/**
+ * dbg_debugfs_exit_fs - remove all debugfs files.
+ * @c: UBIFS file-system description object
+ */
+void dbg_debugfs_exit_fs(struct ubifs_info *c)
+{
+	debugfs_remove_recursive(c->dbg->debugfs_dir);
+}
+
 #endif /* CONFIG_UBIFS_FS_DEBUG */
diff --git a/fs/ubifs/debug.h b/fs/ubifs/debug.h
index d6ea1362d56a..a6b70f8aac9c 100644
--- a/fs/ubifs/debug.h
+++ b/fs/ubifs/debug.h
@@ -43,6 +43,13 @@
  * @new_nhead_offs: used by LPT tree size checker
  * @new_ihead_lnum: used by debugging to check ihead_lnum
  * @new_ihead_offs: used by debugging to check ihead_offs
+ *
+ * debugfs_dir_name: name of debugfs directory containing this file-system's
+ *                   files
+ * debugfs_dir: direntry object of the file-system debugfs directory
+ * dump_lprops: "dump lprops" debugfs knob
+ * dump_budg: "dump budgeting information" debugfs knob
+ * dump_tnc: "dump TNC" debugfs knob
  */
 struct ubifs_debug_info {
 	void *buf;
@@ -61,6 +68,12 @@ struct ubifs_debug_info {
 	int new_nhead_offs;
 	int new_ihead_lnum;
 	int new_ihead_offs;
+
+	char debugfs_dir_name[100];
+	struct dentry *debugfs_dir;
+	struct dentry *dump_lprops;
+	struct dentry *dump_budg;
+	struct dentry *dump_tnc;
 };
 
 #define ubifs_assert(expr) do {                                                \
@@ -251,7 +264,6 @@ int ubifs_debugging_init(struct ubifs_info *c);
 void ubifs_debugging_exit(struct ubifs_info *c);
 
 /* Dump functions */
-
 const char *dbg_ntype(int type);
 const char *dbg_cstate(int cmt_state);
 const char *dbg_get_key_dump(const struct ubifs_info *c,
@@ -274,7 +286,6 @@ void dbg_dump_tnc(struct ubifs_info *c);
 void dbg_dump_index(struct ubifs_info *c);
 
 /* Checking helper functions */
-
 typedef int (*dbg_leaf_callback)(struct ubifs_info *c,
 				 struct ubifs_zbranch *zbr, void *priv);
 typedef int (*dbg_znode_callback)(struct ubifs_info *c,
@@ -354,6 +365,12 @@ static inline int dbg_change(struct ubi_volume_desc *desc, int lnum,
 	return dbg_leb_change(desc, lnum, buf, len, UBI_UNKNOWN);
 }
 
+/* Debugfs-related stuff */
+int dbg_debugfs_init(void);
+void dbg_debugfs_exit(void);
+int dbg_debugfs_init_fs(struct ubifs_info *c);
+void dbg_debugfs_exit_fs(struct ubifs_info *c);
+
 #else /* !CONFIG_UBIFS_FS_DEBUG */
 
 /* Use "if (0)" to make compiler check arguments even if debugging is off */
@@ -434,6 +451,10 @@ static inline int dbg_change(struct ubi_volume_desc *desc, int lnum,
 #define dbg_force_in_the_gaps()                    0
 #define dbg_failure_mode                           0
 
-#endif /* !CONFIG_UBIFS_FS_DEBUG */
+#define dbg_debugfs_init()                         0
+#define dbg_debugfs_exit()
+#define dbg_debugfs_init_fs(c)                     0
+#define dbg_debugfs_exit_fs(c)                     0
 
+#endif /* !CONFIG_UBIFS_FS_DEBUG */
 #endif /* !__UBIFS_DEBUG_H__ */
diff --git a/fs/ubifs/super.c b/fs/ubifs/super.c
index ad44822059c7..2dbaa4fc2cbb 100644
--- a/fs/ubifs/super.c
+++ b/fs/ubifs/super.c
@@ -1258,6 +1258,10 @@ static int mount_ubifs(struct ubifs_info *c)
 		}
 	}
 
+	err = dbg_debugfs_init_fs(c);
+	if (err)
+		goto out_infos;
+
 	err = dbg_check_filesystem(c);
 	if (err)
 		goto out_infos;
@@ -1369,6 +1373,7 @@ static void ubifs_umount(struct ubifs_info *c)
 	dbg_gen("un-mounting UBI device %d, volume %d", c->vi.ubi_num,
 		c->vi.vol_id);
 
+	dbg_debugfs_exit_fs(c);
 	spin_lock(&ubifs_infos_lock);
 	list_del(&c->infos_list);
 	spin_unlock(&ubifs_infos_lock);
@@ -2078,12 +2083,18 @@ static int __init ubifs_init(void)
 	register_shrinker(&ubifs_shrinker_info);
 
 	err = ubifs_compressors_init();
+	if (err)
+		goto out_shrinker;
+
+	err = dbg_debugfs_init();
 	if (err)
 		goto out_compr;
 
 	return 0;
 
 out_compr:
+	ubifs_compressors_exit();
+out_shrinker:
 	unregister_shrinker(&ubifs_shrinker_info);
 	kmem_cache_destroy(ubifs_inode_slab);
 out_reg:
@@ -2098,6 +2109,7 @@ static void __exit ubifs_exit(void)
 	ubifs_assert(list_empty(&ubifs_infos));
 	ubifs_assert(atomic_long_read(&ubifs_clean_zn_cnt) == 0);
 
+	dbg_debugfs_exit();
 	ubifs_compressors_exit();
 	unregister_shrinker(&ubifs_shrinker_info);
 	kmem_cache_destroy(ubifs_inode_slab);
diff --git a/fs/ubifs/ubifs.h b/fs/ubifs/ubifs.h
index 7e090a5e2bf6..4cf28e85de78 100644
--- a/fs/ubifs/ubifs.h
+++ b/fs/ubifs/ubifs.h
@@ -1158,6 +1158,7 @@ struct ubifs_debug_info;
  * @mount_opts: UBIFS-specific mount options
  *
  * @dbg: debugging-related information
+ * @dfs: debugfs support-related information
  */
 struct ubifs_info {
 	struct super_block *vfs_sb;
-- 
cgit v1.2.3


From 45e12d901fee57bccf90f6940155724954e1aac7 Mon Sep 17 00:00:00 2001
From: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Date: Fri, 31 Oct 2008 11:42:18 +0200
Subject: UBIFS: run debugging checks only if they are enabled

Do not forget to check whether lpt debugging is enabled before
running the check functions. This commit also makes some spelling
fixes.

Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
---
 fs/ubifs/lpt.c        | 3 +--
 fs/ubifs/lpt_commit.c | 9 +++++++++
 2 files changed, 10 insertions(+), 2 deletions(-)

diff --git a/fs/ubifs/lpt.c b/fs/ubifs/lpt.c
index db8bd0e518b2..93c181c742f2 100644
--- a/fs/ubifs/lpt.c
+++ b/fs/ubifs/lpt.c
@@ -36,7 +36,7 @@
  * can be written into a single eraseblock. In that case, garbage collection
  * consists of just writing the whole table, which therefore makes all other
  * eraseblocks reusable. In the case of the big model, dirty eraseblocks are
- * selected for garbage collection, which consists are marking the nodes in
+ * selected for garbage collection, which consists of marking the clean nodes in
  * that LEB as dirty, and then only the dirty nodes are written out. Also, in
  * the case of the big model, a table of LEB numbers is saved so that the entire
  * LPT does not to be scanned looking for empty eraseblocks when UBIFS is first
@@ -156,7 +156,6 @@ int ubifs_calc_lpt_geom(struct ubifs_info *c)
 	}
 
 	c->check_lpt_free = c->big_lpt;
-
 	return 0;
 }
 
diff --git a/fs/ubifs/lpt_commit.c b/fs/ubifs/lpt_commit.c
index 1aefab9f0b5e..7bbf03518c7f 100644
--- a/fs/ubifs/lpt_commit.c
+++ b/fs/ubifs/lpt_commit.c
@@ -1604,6 +1604,9 @@ static int dbg_check_ltab_lnum(struct ubifs_info *c, int lnum)
 	int ret;
 	void *buf = c->dbg->buf;
 
+	if (!(ubifs_chk_flags & UBIFS_CHK_LPROPS))
+		return 0;
+
 	dbg_lp("LEB %d", lnum);
 	err = ubi_read(c->ubi, lnum, buf, 0, c->leb_size);
 	if (err) {
@@ -1704,6 +1707,9 @@ int dbg_chk_lpt_free_spc(struct ubifs_info *c)
 	long long free = 0;
 	int i;
 
+	if (!(ubifs_chk_flags & UBIFS_CHK_LPROPS))
+		return 0;
+
 	for (i = 0; i < c->lpt_lebs; i++) {
 		if (c->ltab[i].tgc || c->ltab[i].cmt)
 			continue;
@@ -1735,6 +1741,9 @@ int dbg_chk_lpt_sz(struct ubifs_info *c, int action, int len)
 	long long chk_lpt_sz, lpt_sz;
 	int err = 0;
 
+	if (!(ubifs_chk_flags & UBIFS_CHK_LPROPS))
+		return 0;
+
 	switch (action) {
 	case 0:
 		d->chk_lpt_sz = 0;
-- 
cgit v1.2.3


From 787845bdeadd368eedeace92d5bf53f5aa1450ba Mon Sep 17 00:00:00 2001
From: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Date: Fri, 31 Oct 2008 12:17:42 +0200
Subject: UBIFS: dump stack in LPT check functions

It is useful to know how we got to the checking function when
hunting the bugs.

Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
---
 fs/ubifs/lpt_commit.c | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/fs/ubifs/lpt_commit.c b/fs/ubifs/lpt_commit.c
index 7bbf03518c7f..c5c07f9cd22c 100644
--- a/fs/ubifs/lpt_commit.c
+++ b/fs/ubifs/lpt_commit.c
@@ -320,6 +320,7 @@ no_space:
 	dbg_err("LPT out of space at LEB %d:%d needing %d, done_ltab %d, "
 		"done_lsave %d", lnum, offs, len, done_ltab, done_lsave);
 	dbg_dump_lpt_info(c);
+	dump_stack();
 	return err;
 }
 
@@ -548,6 +549,7 @@ no_space:
 	dbg_err("LPT out of space mismatch at LEB %d:%d needing %d, done_ltab "
 	        "%d, done_lsave %d", lnum, offs, len, done_ltab, done_lsave);
 	dbg_dump_lpt_info(c);
+	dump_stack();
 	return err;
 }
 
@@ -1722,6 +1724,7 @@ int dbg_chk_lpt_free_spc(struct ubifs_info *c)
 		dbg_err("LPT space error: free %lld lpt_sz %lld",
 			free, c->lpt_sz);
 		dbg_dump_lpt_info(c);
+		dump_stack();
 		return -EINVAL;
 	}
 	return 0;
@@ -1803,8 +1806,10 @@ int dbg_chk_lpt_sz(struct ubifs_info *c, int action, int len)
 				d->chk_lpt_sz, d->chk_lpt_wastage, lpt_sz);
 			err = -EINVAL;
 		}
-		if (err)
+		if (err) {
 			dbg_dump_lpt_info(c);
+			dump_stack();
+		}
 		d->chk_lpt_sz2 = d->chk_lpt_sz;
 		d->chk_lpt_sz = 0;
 		d->chk_lpt_wastage = 0;
-- 
cgit v1.2.3


From 2ba5f7ae8165b3f575dd3a7d8bb18f421fab8273 Mon Sep 17 00:00:00 2001
From: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Date: Fri, 31 Oct 2008 17:32:30 +0200
Subject: UBIFS: introduce LPT dump function

Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
---
 fs/ubifs/debug.c      |  28 +++++++----
 fs/ubifs/debug.h      |  45 +++++++++--------
 fs/ubifs/lpt.c        |  27 ++++++-----
 fs/ubifs/lpt_commit.c | 131 ++++++++++++++++++++++++++++++++++++++++++++++++--
 fs/ubifs/ubifs.h      |   3 ++
 5 files changed, 186 insertions(+), 48 deletions(-)

diff --git a/fs/ubifs/debug.c b/fs/ubifs/debug.c
index 56842772c804..934db1855f09 100644
--- a/fs/ubifs/debug.c
+++ b/fs/ubifs/debug.c
@@ -646,7 +646,8 @@ void dbg_dump_lprops(struct ubifs_info *c)
 	struct ubifs_lprops lp;
 	struct ubifs_lp_stats lst;
 
-	printk(KERN_DEBUG "(pid %d) Dumping LEB properties\n", current->pid);
+	printk(KERN_DEBUG "(pid %d) start dumping LEB properties\n",
+	       current->pid);
 	ubifs_get_lp_stats(c, &lst);
 	dbg_dump_lstats(&lst);
 
@@ -657,6 +658,8 @@ void dbg_dump_lprops(struct ubifs_info *c)
 
 		dbg_dump_lprop(c, &lp);
 	}
+	printk(KERN_DEBUG "(pid %d) finish dumping LEB properties\n",
+	       current->pid);
 }
 
 void dbg_dump_lpt_info(struct ubifs_info *c)
@@ -664,6 +667,7 @@ void dbg_dump_lpt_info(struct ubifs_info *c)
 	int i;
 
 	spin_lock(&dbg_lock);
+	printk(KERN_DEBUG "(pid %d) dumping LPT information\n", current->pid);
 	printk(KERN_DEBUG "\tlpt_sz:        %lld\n", c->lpt_sz);
 	printk(KERN_DEBUG "\tpnode_sz:      %d\n", c->pnode_sz);
 	printk(KERN_DEBUG "\tnnode_sz:      %d\n", c->nnode_sz);
@@ -704,8 +708,8 @@ void dbg_dump_leb(const struct ubifs_info *c, int lnum)
 	if (dbg_failure_mode)
 		return;
 
-	printk(KERN_DEBUG "(pid %d) Dumping LEB %d\n", current->pid, lnum);
-
+	printk(KERN_DEBUG "(pid %d) start dumping LEB %d\n",
+	       current->pid, lnum);
 	sleb = ubifs_scan(c, lnum, 0, c->dbg->buf);
 	if (IS_ERR(sleb)) {
 		ubifs_err("scan error %d", (int)PTR_ERR(sleb));
@@ -722,6 +726,8 @@ void dbg_dump_leb(const struct ubifs_info *c, int lnum)
 		dbg_dump_node(c, snod->node);
 	}
 
+	printk(KERN_DEBUG "(pid %d) finish dumping LEB %d\n",
+	       current->pid, lnum);
 	ubifs_scan_destroy(sleb);
 	return;
 }
@@ -769,7 +775,7 @@ void dbg_dump_heap(struct ubifs_info *c, struct ubifs_lpt_heap *heap, int cat)
 {
 	int i;
 
-	printk(KERN_DEBUG "(pid %d) Dumping heap cat %d (%d elements)\n",
+	printk(KERN_DEBUG "(pid %d) start dumping heap cat %d (%d elements)\n",
 	       current->pid, cat, heap->cnt);
 	for (i = 0; i < heap->cnt; i++) {
 		struct ubifs_lprops *lprops = heap->arr[i];
@@ -778,6 +784,7 @@ void dbg_dump_heap(struct ubifs_info *c, struct ubifs_lpt_heap *heap, int cat)
 		       "flags %d\n", i, lprops->lnum, lprops->hpos,
 		       lprops->free, lprops->dirty, lprops->flags);
 	}
+	printk(KERN_DEBUG "(pid %d) finish dumping heap\n", current->pid);
 }
 
 void dbg_dump_pnode(struct ubifs_info *c, struct ubifs_pnode *pnode,
@@ -785,7 +792,7 @@ void dbg_dump_pnode(struct ubifs_info *c, struct ubifs_pnode *pnode,
 {
 	int i;
 
-	printk(KERN_DEBUG "(pid %d) Dumping pnode:\n", current->pid);
+	printk(KERN_DEBUG "(pid %d) dumping pnode:\n", current->pid);
 	printk(KERN_DEBUG "\taddress %zx parent %zx cnext %zx\n",
 	       (size_t)pnode, (size_t)parent, (size_t)pnode->cnext);
 	printk(KERN_DEBUG "\tflags %lu iip %d level %d num %d\n",
@@ -804,7 +811,7 @@ void dbg_dump_tnc(struct ubifs_info *c)
 	int level;
 
 	printk(KERN_DEBUG "\n");
-	printk(KERN_DEBUG "(pid %d) Dumping the TNC tree\n", current->pid);
+	printk(KERN_DEBUG "(pid %d) start dumping TNC tree\n", current->pid);
 	znode = ubifs_tnc_levelorder_next(c->zroot.znode, NULL);
 	level = znode->level;
 	printk(KERN_DEBUG "== Level %d ==\n", level);
@@ -816,8 +823,7 @@ void dbg_dump_tnc(struct ubifs_info *c)
 		dbg_dump_znode(c, znode);
 		znode = ubifs_tnc_levelorder_next(c->zroot.znode, znode);
 	}
-
-	printk(KERN_DEBUG "\n");
+	printk(KERN_DEBUG "(pid %d) finish dumping TNC tree\n", current->pid);
 }
 
 static int dump_znode(struct ubifs_info *c, struct ubifs_znode *znode,
@@ -992,7 +998,8 @@ static int dbg_check_key_order(struct ubifs_info *c, struct ubifs_zbranch *zbr1,
 		ubifs_err("1st entry at %d:%d has key %s", zbr1->lnum,
 			  zbr1->offs, DBGKEY(&key));
 		ubifs_err("but it should have key %s according to tnc",
-			  DBGKEY(&zbr1->key)); dbg_dump_node(c, dent1);
+			  DBGKEY(&zbr1->key));
+		dbg_dump_node(c, dent1);
 		goto out_free;
 	}
 
@@ -1001,7 +1008,8 @@ static int dbg_check_key_order(struct ubifs_info *c, struct ubifs_zbranch *zbr1,
 		ubifs_err("2nd entry at %d:%d has key %s", zbr1->lnum,
 			  zbr1->offs, DBGKEY(&key));
 		ubifs_err("but it should have key %s according to tnc",
-			  DBGKEY(&zbr2->key)); dbg_dump_node(c, dent2);
+			  DBGKEY(&zbr2->key));
+		dbg_dump_node(c, dent2);
 		goto out_free;
 	}
 
diff --git a/fs/ubifs/debug.h b/fs/ubifs/debug.h
index a6b70f8aac9c..9820d6999f7e 100644
--- a/fs/ubifs/debug.h
+++ b/fs/ubifs/debug.h
@@ -270,6 +270,8 @@ const char *dbg_get_key_dump(const struct ubifs_info *c,
 			     const union ubifs_key *key);
 void dbg_dump_inode(const struct ubifs_info *c, const struct inode *inode);
 void dbg_dump_node(const struct ubifs_info *c, const void *node);
+void dbg_dump_lpt_node(const struct ubifs_info *c, void *node, int lnum,
+		       int offs);
 void dbg_dump_budget_req(const struct ubifs_budget_req *req);
 void dbg_dump_lstats(const struct ubifs_lp_stats *lst);
 void dbg_dump_budg(struct ubifs_info *c);
@@ -284,6 +286,7 @@ void dbg_dump_pnode(struct ubifs_info *c, struct ubifs_pnode *pnode,
 		    struct ubifs_nnode *parent, int iip);
 void dbg_dump_tnc(struct ubifs_info *c);
 void dbg_dump_index(struct ubifs_info *c);
+void dbg_dump_lpt_lebs(const struct ubifs_info *c);
 
 /* Checking helper functions */
 typedef int (*dbg_leaf_callback)(struct ubifs_info *c,
@@ -411,26 +414,28 @@ void dbg_debugfs_exit_fs(struct ubifs_info *c);
 #define DBGKEY(key)  ((char *)(key))
 #define DBGKEY1(key) ((char *)(key))
 
-#define ubifs_debugging_init(c)               0
-#define ubifs_debugging_exit(c)               ({})
-
-#define dbg_ntype(type)                       ""
-#define dbg_cstate(cmt_state)                 ""
-#define dbg_get_key_dump(c, key)              ({})
-#define dbg_dump_inode(c, inode)              ({})
-#define dbg_dump_node(c, node)                ({})
-#define dbg_dump_budget_req(req)              ({})
-#define dbg_dump_lstats(lst)                  ({})
-#define dbg_dump_budg(c)                      ({})
-#define dbg_dump_lprop(c, lp)                 ({})
-#define dbg_dump_lprops(c)                    ({})
-#define dbg_dump_lpt_info(c)                  ({})
-#define dbg_dump_leb(c, lnum)                 ({})
-#define dbg_dump_znode(c, znode)              ({})
-#define dbg_dump_heap(c, heap, cat)           ({})
-#define dbg_dump_pnode(c, pnode, parent, iip) ({})
-#define dbg_dump_tnc(c)                       ({})
-#define dbg_dump_index(c)                     ({})
+#define ubifs_debugging_init(c)                0
+#define ubifs_debugging_exit(c)                ({})
+
+#define dbg_ntype(type)                        ""
+#define dbg_cstate(cmt_state)                  ""
+#define dbg_get_key_dump(c, key)               ({})
+#define dbg_dump_inode(c, inode)               ({})
+#define dbg_dump_node(c, node)                 ({})
+#define dbg_dump_lpt_node(c, node, lnum, offs) ({})
+#define dbg_dump_budget_req(req)               ({})
+#define dbg_dump_lstats(lst)                   ({})
+#define dbg_dump_budg(c)                       ({})
+#define dbg_dump_lprop(c, lp)                  ({})
+#define dbg_dump_lprops(c)                     ({})
+#define dbg_dump_lpt_info(c)                   ({})
+#define dbg_dump_leb(c, lnum)                  ({})
+#define dbg_dump_znode(c, znode)               ({})
+#define dbg_dump_heap(c, heap, cat)            ({})
+#define dbg_dump_pnode(c, pnode, parent, iip)  ({})
+#define dbg_dump_tnc(c)                        ({})
+#define dbg_dump_index(c)                      ({})
+#define dbg_dump_lpt_lebs(c)                   ({})
 
 #define dbg_walk_index(c, leaf_cb, znode_cb, priv) 0
 #define dbg_old_index_check_init(c, zroot)         0
diff --git a/fs/ubifs/lpt.c b/fs/ubifs/lpt.c
index 93c181c742f2..6d914160ec55 100644
--- a/fs/ubifs/lpt.c
+++ b/fs/ubifs/lpt.c
@@ -557,7 +557,7 @@ static int calc_nnode_num(int row, int col)
  * This function calculates and returns the nnode number based on the parent's
  * nnode number and the index in parent.
  */
-static int calc_nnode_num_from_parent(struct ubifs_info *c,
+static int calc_nnode_num_from_parent(const struct ubifs_info *c,
 				      struct ubifs_nnode *parent, int iip)
 {
 	int num, shft;
@@ -582,7 +582,7 @@ static int calc_nnode_num_from_parent(struct ubifs_info *c,
  * This function calculates and returns the pnode number based on the parent's
  * nnode number and the index in parent.
  */
-static int calc_pnode_num_from_parent(struct ubifs_info *c,
+static int calc_pnode_num_from_parent(const struct ubifs_info *c,
 				      struct ubifs_nnode *parent, int iip)
 {
 	int i, n = c->lpt_hght - 1, pnum = parent->num, num = 0;
@@ -965,7 +965,7 @@ static int check_lpt_type(uint8_t **addr, int *pos, int type)
  *
  * This function returns %0 on success and a negative error code on failure.
  */
-static int unpack_pnode(struct ubifs_info *c, void *buf,
+static int unpack_pnode(const struct ubifs_info *c, void *buf,
 			struct ubifs_pnode *pnode)
 {
 	uint8_t *addr = buf + UBIFS_LPT_CRC_BYTES;
@@ -995,15 +995,15 @@ static int unpack_pnode(struct ubifs_info *c, void *buf,
 }
 
 /**
- * unpack_nnode - unpack a nnode.
+ * ubifs_unpack_nnode - unpack a nnode.
  * @c: UBIFS file-system description object
  * @buf: buffer containing packed nnode to unpack
  * @nnode: nnode structure to fill
  *
  * This function returns %0 on success and a negative error code on failure.
  */
-static int unpack_nnode(struct ubifs_info *c, void *buf,
-			struct ubifs_nnode *nnode)
+int ubifs_unpack_nnode(const struct ubifs_info *c, void *buf,
+		       struct ubifs_nnode *nnode)
 {
 	uint8_t *addr = buf + UBIFS_LPT_CRC_BYTES;
 	int i, pos = 0, err;
@@ -1035,7 +1035,7 @@ static int unpack_nnode(struct ubifs_info *c, void *buf,
  *
  * This function returns %0 on success and a negative error code on failure.
  */
-static int unpack_ltab(struct ubifs_info *c, void *buf)
+static int unpack_ltab(const struct ubifs_info *c, void *buf)
 {
 	uint8_t *addr = buf + UBIFS_LPT_CRC_BYTES;
 	int i, pos = 0, err;
@@ -1067,7 +1067,7 @@ static int unpack_ltab(struct ubifs_info *c, void *buf)
  *
  * This function returns %0 on success and a negative error code on failure.
  */
-static int unpack_lsave(struct ubifs_info *c, void *buf)
+static int unpack_lsave(const struct ubifs_info *c, void *buf)
 {
 	uint8_t *addr = buf + UBIFS_LPT_CRC_BYTES;
 	int i, pos = 0, err;
@@ -1095,7 +1095,7 @@ static int unpack_lsave(struct ubifs_info *c, void *buf)
  *
  * This function returns %0 on success and a negative error code on failure.
  */
-static int validate_nnode(struct ubifs_info *c, struct ubifs_nnode *nnode,
+static int validate_nnode(const struct ubifs_info *c, struct ubifs_nnode *nnode,
 			  struct ubifs_nnode *parent, int iip)
 {
 	int i, lvl, max_offs;
@@ -1139,7 +1139,7 @@ static int validate_nnode(struct ubifs_info *c, struct ubifs_nnode *nnode,
  *
  * This function returns %0 on success and a negative error code on failure.
  */
-static int validate_pnode(struct ubifs_info *c, struct ubifs_pnode *pnode,
+static int validate_pnode(const struct ubifs_info *c, struct ubifs_pnode *pnode,
 			  struct ubifs_nnode *parent, int iip)
 {
 	int i;
@@ -1173,7 +1173,8 @@ static int validate_pnode(struct ubifs_info *c, struct ubifs_pnode *pnode,
  * This function calculates the LEB numbers for the LEB properties it contains
  * based on the pnode number.
  */
-static void set_pnode_lnum(struct ubifs_info *c, struct ubifs_pnode *pnode)
+static void set_pnode_lnum(const struct ubifs_info *c,
+			   struct ubifs_pnode *pnode)
 {
 	int i, lnum;
 
@@ -1226,7 +1227,7 @@ int ubifs_read_nnode(struct ubifs_info *c, struct ubifs_nnode *parent, int iip)
 		err = ubi_read(c->ubi, lnum, buf, offs, c->nnode_sz);
 		if (err)
 			goto out;
-		err = unpack_nnode(c, buf, nnode);
+		err = ubifs_unpack_nnode(c, buf, nnode);
 		if (err)
 			goto out;
 	}
@@ -1815,7 +1816,7 @@ static struct ubifs_nnode *scan_get_nnode(struct ubifs_info *c,
 			       c->nnode_sz);
 		if (err)
 			return ERR_PTR(err);
-		e