From bc86cf7af2ebda88056538e8edff852ee627f76a Mon Sep 17 00:00:00 2001
From: Brian Norris <computersforpeace@gmail.com>
Date: Tue, 9 Oct 2012 23:26:06 -0700
Subject: [PATCH 1/7] mtd: nand: fix Samsung SLC NAND identification regression

A combination of the following two commits caused a regression in 3.7-rc1
when identifying some Samsung NAND, so that some previously working NAND
were no longer detected properly:

    commit e3b88bd604283ef83ae6e8f53622d5b1ffe9d43a
    mtd: nand: add generic READ ID length calculation functions

    commit e2d3a35ee427aaba99b6c68a56609ce276c51270
    mtd: nand: detect Samsung K9GBG08U0A, K9GAG08U0F ID

Particularly, a regression was seen on Samsung K9F2G08U0B, with the
following full 8-byte READ ID string:

    ec da 10 95 44 00 ec da

The basic problem is that Samsung manufactures both SLC and MLC NAND
that use a non-standard decoding table for deriving information from
their IDs. I have heuristically determined that all the chips that use
the new table have ID strings which wrap around after the 6th byte.
Unfortunately, I overlooked the fact that some older Samsung SLC (which
use a different decoding table) have "5 byte ID strings" which also wrap
around after the 6th byte.

This patch re-introduces a distinction between these old and new Samsung
NAND by checking that the 6th byte is non-zero, allowing both old and
new Samsung NAND to be detected properly.

Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Tested-by: Brian Norris <computersforpeace@gmail.com>
Reported-by: Marek Vasut <marex@denx.de>
Tested-by: Marek Vasut <marex@denx.de>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
---
 drivers/mtd/nand/nand_base.c | 9 +++++----
 1 file changed, 5 insertions(+), 4 deletions(-)

diff --git a/drivers/mtd/nand/nand_base.c b/drivers/mtd/nand/nand_base.c
index ec6841d8e956..d5ece6ea6f98 100644
--- a/drivers/mtd/nand/nand_base.c
+++ b/drivers/mtd/nand/nand_base.c
@@ -2983,13 +2983,14 @@ static void nand_decode_ext_id(struct mtd_info *mtd, struct nand_chip *chip,
 	/*
 	 * Field definitions are in the following datasheets:
 	 * Old style (4,5 byte ID): Samsung K9GAG08U0M (p.32)
-	 * New style   (6 byte ID): Samsung K9GAG08U0F (p.44)
+	 * New Samsung (6 byte ID): Samsung K9GAG08U0F (p.44)
 	 * Hynix MLC   (6 byte ID): Hynix H27UBG8T2B (p.22)
 	 *
-	 * Check for ID length, cell type, and Hynix/Samsung ID to decide what
-	 * to do.
+	 * Check for ID length, non-zero 6th byte, cell type, and Hynix/Samsung
+	 * ID to decide what to do.
 	 */
-	if (id_len == 6 && id_data[0] == NAND_MFR_SAMSUNG) {
+	if (id_len == 6 && id_data[0] == NAND_MFR_SAMSUNG &&
+			id_data[5] != 0x00) {
 		/* Calc pagesize */
 		mtd->writesize = 2048 << (extid & 0x03);
 		extid >>= 2;

From 5a6ea4af0907f995dc06df21a9c9ef764c7cd3bc Mon Sep 17 00:00:00 2001
From: Sachin Kamat <sachin.kamat@linaro.org>
Date: Tue, 25 Sep 2012 15:27:13 +0530
Subject: [PATCH 2/7] mtd: ofpart: Fix incorrect NULL check in
 parse_ofoldpart_partitions()

The pointer returned by kzalloc should be tested for NULL
to avoid potential NULL pointer dereference later. Incorrect
pointer was being tested for NULL. Bug introduced by commit fbcf62a3
(mtd: physmap_of: move parse_obsolete_partitions to become separate
parser).
This patch fixes this bug.

Cc: Dmitry Eremin-Solenikov <dbaryshkov@gmail.com>
Cc: Artem Bityutskiy <artem.bityutskiy@intel.com>
Cc: stable@kernel.org
Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
---
 drivers/mtd/ofpart.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/mtd/ofpart.c b/drivers/mtd/ofpart.c
index 64be8f0848b0..d9127e2ed808 100644
--- a/drivers/mtd/ofpart.c
+++ b/drivers/mtd/ofpart.c
@@ -121,7 +121,7 @@ static int parse_ofoldpart_partitions(struct mtd_info *master,
 	nr_parts = plen / sizeof(part[0]);
 
 	*pparts = kzalloc(nr_parts * sizeof(*(*pparts)), GFP_KERNEL);
-	if (!pparts)
+	if (!*pparts)
 		return -ENOMEM;
 
 	names = of_get_property(dp, "partition-names", &plen);

From c36a7ff4578ab6294885aef5ef241aeec4cdb1f0 Mon Sep 17 00:00:00 2001
From: Jiri Engelthaler <engycz@gmail.com>
Date: Thu, 20 Sep 2012 16:49:50 +0200
Subject: [PATCH 3/7] mtd: slram: invalid checking of absolute end address

Fixed parsing end absolute address.

Signed-off-by: Jiri Engelthaler <engycz@gmail.com>
Cc: stable@vger.kernel.org
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
---
 drivers/mtd/devices/slram.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/mtd/devices/slram.c b/drivers/mtd/devices/slram.c
index 8f52fc858e48..5a5cd2ace4a6 100644
--- a/drivers/mtd/devices/slram.c
+++ b/drivers/mtd/devices/slram.c
@@ -240,7 +240,7 @@ static int parse_cmdline(char *devname, char *szstart, char *szlength)
 
 	if (*(szlength) != '+') {
 		devlength = simple_strtoul(szlength, &buffer, 0);
-		devlength = handle_unit(devlength, buffer) - devstart;
+		devlength = handle_unit(devlength, buffer);
 		if (devlength < devstart)
 			goto err_out;
 

From 0131950ebd146b5e31508233352d6f4625af25b1 Mon Sep 17 00:00:00 2001
From: Sachin Kamat <sachin.kamat@linaro.org>
Date: Sat, 22 Sep 2012 11:42:31 +0530
Subject: [PATCH 4/7] mtd: onenand: Make flexonenand_set_boundary static

Fixes the following sparse warning:
drivers/mtd/onenand/onenand_base.c:3697:5: warning:
symbol 'flexonenand_set_boundary' was not declared. Should it be static?

Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org>
Acked-by: Kyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
---
 drivers/mtd/onenand/onenand_base.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/mtd/onenand/onenand_base.c b/drivers/mtd/onenand/onenand_base.c
index 7153e0d27101..b3f41f200622 100644
--- a/drivers/mtd/onenand/onenand_base.c
+++ b/drivers/mtd/onenand/onenand_base.c
@@ -3694,7 +3694,7 @@ static int flexonenand_check_blocks_erased(struct mtd_info *mtd, int start, int
  * flexonenand_set_boundary	- Writes the SLC boundary
  * @param mtd			- mtd info structure
  */
-int flexonenand_set_boundary(struct mtd_info *mtd, int die,
+static int flexonenand_set_boundary(struct mtd_info *mtd, int die,
 				    int boundary, int lock)
 {
 	struct onenand_chip *this = mtd->priv;

From 5ffd3412ae5536a4c57469cb8ea31887121dcb2e Mon Sep 17 00:00:00 2001
From: Thomas Betker <thomas.betker@freenet.de>
Date: Wed, 17 Oct 2012 22:59:30 +0200
Subject: [PATCH 5/7] jffs2: Fix lock acquisition order bug in
 jffs2_write_begin

jffs2_write_begin() first acquires the page lock, then f->sem. This
causes an AB-BA deadlock with jffs2_garbage_collect_live(), which first
acquires f->sem, then the page lock:

jffs2_garbage_collect_live
    mutex_lock(&f->sem)                         (A)
    jffs2_garbage_collect_dnode
        jffs2_gc_fetch_page
            read_cache_page_async
                do_read_cache_page
                    lock_page(page)             (B)

jffs2_write_begin
    grab_cache_page_write_begin
        find_lock_page
            lock_page(page)                     (B)
    mutex_lock(&f->sem)                         (A)

We fix this by restructuring jffs2_write_begin() to take f->sem before
the page lock. However, we make sure that f->sem is not held when
calling jffs2_reserve_space(), as this is not permitted by the locking
rules.

The deadlock above was observed multiple times on an SoC with a dual
ARMv7 (Cortex-A9), running the long-term 3.4.11 kernel; it occurred
when using scp to copy files from a host system to the ARM target
system. The fix was heavily tested on the same target system.

Cc: stable@vger.kernel.org
Signed-off-by: Thomas Betker <thomas.betker@rohde-schwarz.com>
Acked-by: Joakim Tjernlund <Joakim.Tjernlund@transmode.se>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
---
 fs/jffs2/file.c | 41 ++++++++++++++++++++++-------------------
 1 file changed, 22 insertions(+), 19 deletions(-)

diff --git a/fs/jffs2/file.c b/fs/jffs2/file.c
index 60ef3fb707ff..1506673c087e 100644
--- a/fs/jffs2/file.c
+++ b/fs/jffs2/file.c
@@ -138,33 +138,39 @@ static int jffs2_write_begin(struct file *filp, struct address_space *mapping,
 	struct page *pg;
 	struct inode *inode = mapping->host;
 	struct jffs2_inode_info *f = JFFS2_INODE_INFO(inode);
+	struct jffs2_sb_info *c = JFFS2_SB_INFO(inode->i_sb);
+	struct jffs2_raw_inode ri;
+	uint32_t alloc_len = 0;
 	pgoff_t index = pos >> PAGE_CACHE_SHIFT;
 	uint32_t pageofs = index << PAGE_CACHE_SHIFT;
 	int ret = 0;
 
-	pg = grab_cache_page_write_begin(mapping, index, flags);
-	if (!pg)
-		return -ENOMEM;
-	*pagep = pg;
-
 	jffs2_dbg(1, "%s()\n", __func__);
 
 	if (pageofs > inode->i_size) {
+		ret = jffs2_reserve_space(c, sizeof(ri), &alloc_len,
+					  ALLOC_NORMAL, JFFS2_SUMMARY_INODE_SIZE);
+		if (ret)
+			return ret;
+	}
+
+	mutex_lock(&f->sem);
+	pg = grab_cache_page_write_begin(mapping, index, flags);
+	if (!pg) {
+		if (alloc_len)
+			jffs2_complete_reservation(c);
+		mutex_unlock(&f->sem);
+		return -ENOMEM;
+	}
+	*pagep = pg;
+
+	if (alloc_len) {
 		/* Make new hole frag from old EOF to new page */
-		struct jffs2_sb_info *c = JFFS2_SB_INFO(inode->i_sb);
-		struct jffs2_raw_inode ri;
 		struct jffs2_full_dnode *fn;
-		uint32_t alloc_len;
 
 		jffs2_dbg(1, "Writing new hole frag 0x%x-0x%x between current EOF and new page\n",
 			  (unsigned int)inode->i_size, pageofs);
 
-		ret = jffs2_reserve_space(c, sizeof(ri), &alloc_len,
-					  ALLOC_NORMAL, JFFS2_SUMMARY_INODE_SIZE);
-		if (ret)
-			goto out_page;
-
-		mutex_lock(&f->sem);
 		memset(&ri, 0, sizeof(ri));
 
 		ri.magic = cpu_to_je16(JFFS2_MAGIC_BITMASK);
@@ -191,7 +197,6 @@ static int jffs2_write_begin(struct file *filp, struct address_space *mapping,
 		if (IS_ERR(fn)) {
 			ret = PTR_ERR(fn);
 			jffs2_complete_reservation(c);
-			mutex_unlock(&f->sem);
 			goto out_page;
 		}
 		ret = jffs2_add_full_dnode_to_inode(c, f, fn);
@@ -206,12 +211,10 @@ static int jffs2_write_begin(struct file *filp, struct address_space *mapping,
 			jffs2_mark_node_obsolete(c, fn->raw);
 			jffs2_free_full_dnode(fn);
 			jffs2_complete_reservation(c);
-			mutex_unlock(&f->sem);
 			goto out_page;
 		}
 		jffs2_complete_reservation(c);
 		inode->i_size = pageofs;
-		mutex_unlock(&f->sem);
 	}
 
 	/*
@@ -220,18 +223,18 @@ static int jffs2_write_begin(struct file *filp, struct address_space *mapping,
 	 * case of a short-copy.
 	 */
 	if (!PageUptodate(pg)) {
-		mutex_lock(&f->sem);
 		ret = jffs2_do_readpage_nolock(inode, pg);
-		mutex_unlock(&f->sem);
 		if (ret)
 			goto out_page;
 	}
+	mutex_unlock(&f->sem);
 	jffs2_dbg(1, "end write_begin(). pg->flags %lx\n", pg->flags);
 	return ret;
 
 out_page:
 	unlock_page(pg);
 	page_cache_release(pg);
+	mutex_unlock(&f->sem);
 	return ret;
 }
 

From af451af4e0a3a4cd7536843f585c96a9b095a4e8 Mon Sep 17 00:00:00 2001
From: Brian Norris <computersforpeace@gmail.com>
Date: Tue, 9 Oct 2012 23:26:06 -0700
Subject: [PATCH 6/7] mtd: nand: fix Samsung SLC NAND identification regression

A combination of the following two commits caused a regression in 3.7-rc1
when identifying some Samsung NAND, so that some previously working NAND
were no longer detected properly:

    commit e3b88bd604283ef83ae6e8f53622d5b1ffe9d43a
    mtd: nand: add generic READ ID length calculation functions

    commit e2d3a35ee427aaba99b6c68a56609ce276c51270
    mtd: nand: detect Samsung K9GBG08U0A, K9GAG08U0F ID

Particularly, a regression was seen on Samsung K9F2G08U0B, with the
following full 8-byte READ ID string:

    ec da 10 95 44 00 ec da

The basic problem is that Samsung manufactures both SLC and MLC NAND
that use a non-standard decoding table for deriving information from
their IDs. I have heuristically determined that all the chips that use
the new table have ID strings which wrap around after the 6th byte.
Unfortunately, I overlooked the fact that some older Samsung SLC (which
use a different decoding table) have "5 byte ID strings" which also wrap
around after the 6th byte.

This patch re-introduces a distinction between these old and new Samsung
NAND by checking that the 6th byte is non-zero, allowing both old and
new Samsung NAND to be detected properly.

Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Tested-by: Brian Norris <computersforpeace@gmail.com>
Reported-by: Marek Vasut <marex@denx.de>
Tested-by: Marek Vasut <marex@denx.de>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
---
 drivers/mtd/nand/nand_base.c | 9 +++++----
 1 file changed, 5 insertions(+), 4 deletions(-)

diff --git a/drivers/mtd/nand/nand_base.c b/drivers/mtd/nand/nand_base.c
index ec6841d8e956..d5ece6ea6f98 100644
--- a/drivers/mtd/nand/nand_base.c
+++ b/drivers/mtd/nand/nand_base.c
@@ -2983,13 +2983,14 @@ static void nand_decode_ext_id(struct mtd_info *mtd, struct nand_chip *chip,
 	/*
 	 * Field definitions are in the following datasheets:
 	 * Old style (4,5 byte ID): Samsung K9GAG08U0M (p.32)
-	 * New style   (6 byte ID): Samsung K9GAG08U0F (p.44)
+	 * New Samsung (6 byte ID): Samsung K9GAG08U0F (p.44)
 	 * Hynix MLC   (6 byte ID): Hynix H27UBG8T2B (p.22)
 	 *
-	 * Check for ID length, cell type, and Hynix/Samsung ID to decide what
-	 * to do.
+	 * Check for ID length, non-zero 6th byte, cell type, and Hynix/Samsung
+	 * ID to decide what to do.
 	 */
-	if (id_len == 6 && id_data[0] == NAND_MFR_SAMSUNG) {
+	if (id_len == 6 && id_data[0] == NAND_MFR_SAMSUNG &&
+			id_data[5] != 0x00) {
 		/* Calc pagesize */
 		mtd->writesize = 2048 << (extid & 0x03);
 		extid >>= 2;

From 6924d99fcdf1a688538a3cdebd1f135c22eec191 Mon Sep 17 00:00:00 2001
From: Brian Norris <computersforpeace@gmail.com>
Date: Wed, 14 Nov 2012 21:46:30 -0800
Subject: [PATCH 7/7] mtd: nand: fix Samsung SLC detection regression

This patch fixes errors seen in identifying old Samsung SLC, due to the
following commits:

    commit e2d3a35ee427aaba99b6c68a56609ce276c51270
    mtd: nand: detect Samsung K9GBG08U0A, K9GAG08U0F ID

    commit e3b88bd604283ef83ae6e8f53622d5b1ffe9d43a
    mtd: nand: add generic READ ID length calculation functions

Some Samsung NAND with "5-byte" ID really appear to have 6-byte IDs, with
wraparound like:

  Samsung K9K8G08U0D
  ec d3 51 95 58 ec ec d3

  Samsung K9F1G08U0C
  ec f1 00 95 40 ec ec f1

  Samsung K9F2G08U0B
  ec da 10 95 44 00 ec da

This bad wraparound makes it hard to reliably detect the difference
between Samsung SLC with 5-byte ID and Samsung SLC with 6-byte ID.

The fix is to, for now, only use the new Samsung table for MLC. We
cannot support the new SLC (K9FAG08U0M) until Samsung gives better ID
decode information.

Note that this applies in addition to the previous regression fix:

    commit bc86cf7af2ebda88056538e8edff852ee627f76a
    mtd: nand: fix Samsung SLC NAND identification regression

Together, these patches completely restore the previous detection
behavior so that we cannot see any more regressions in Samsung SLC NAND
(finger crossed). With luck, I can get a hold of a Samsung
representative and stop having to cross my fingers eventually.

Reported-by: Sylwester Nawrocki <sylvester.nawrocki@gmail.com>
Tested-by: Sylwester Nawrocki <sylvester.nawrocki@gmail.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
---
 drivers/mtd/nand/nand_base.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/mtd/nand/nand_base.c b/drivers/mtd/nand/nand_base.c
index d5ece6ea6f98..1a03b7f673ce 100644
--- a/drivers/mtd/nand/nand_base.c
+++ b/drivers/mtd/nand/nand_base.c
@@ -2990,6 +2990,7 @@ static void nand_decode_ext_id(struct mtd_info *mtd, struct nand_chip *chip,
 	 * ID to decide what to do.
 	 */
 	if (id_len == 6 && id_data[0] == NAND_MFR_SAMSUNG &&
+			(chip->cellinfo & NAND_CI_CELLTYPE_MSK) &&
 			id_data[5] != 0x00) {
 		/* Calc pagesize */
 		mtd->writesize = 2048 << (extid & 0x03);