From 24a5d59f3477bcff4c069ff4d0ca9a3e037d0235 Mon Sep 17 00:00:00 2001
From: Jan Kara <jack@suse.cz>
Date: Thu, 18 Jun 2009 12:33:16 +0200
Subject: [PATCH 1/2] udf: Use device size when drive reported bogus number of
 written blocks

Some drives report 0 as the number of written blocks when there are some blocks
recorded. Use device size in such case so that we can automagically mount such
media.

Signed-off-by: Jan Kara <jack@suse.cz>
---
 fs/udf/lowlevel.c | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/fs/udf/lowlevel.c b/fs/udf/lowlevel.c
index 703843f30ffd3..1b88fd5df05d6 100644
--- a/fs/udf/lowlevel.c
+++ b/fs/udf/lowlevel.c
@@ -56,7 +56,12 @@ unsigned long udf_get_last_block(struct super_block *sb)
 	struct block_device *bdev = sb->s_bdev;
 	unsigned long lblock = 0;
 
-	if (ioctl_by_bdev(bdev, CDROM_LAST_WRITTEN, (unsigned long) &lblock))
+	/*
+	 * ioctl failed or returned obviously bogus value?
+	 * Try using the device size...
+	 */
+	if (ioctl_by_bdev(bdev, CDROM_LAST_WRITTEN, (unsigned long) &lblock) ||
+	    lblock == 0)
 		lblock = bdev->bd_inode->i_size >> sb->s_blocksize_bits;
 
 	if (lblock)

From 3391faa4f18e4e33666d3d24e90e3086fcf9b922 Mon Sep 17 00:00:00 2001
From: Roel Kluin <roel.kluin@gmail.com>
Date: Mon, 22 Jun 2009 23:12:29 +0200
Subject: [PATCH 2/2] udf: remove redundant tests on unsigned

first_block and goal are unsigned. When negative they are wrapped and caught by
the other test.

Signed-off-by: Roel Kluin <roel.kluin@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>
---
 fs/udf/balloc.c | 9 ++++-----
 1 file changed, 4 insertions(+), 5 deletions(-)

diff --git a/fs/udf/balloc.c b/fs/udf/balloc.c
index e48e9a3af7631..1e068535b58bf 100644
--- a/fs/udf/balloc.c
+++ b/fs/udf/balloc.c
@@ -238,7 +238,7 @@ static int udf_bitmap_prealloc_blocks(struct super_block *sb,
 
 	mutex_lock(&sbi->s_alloc_mutex);
 	part_len = sbi->s_partmaps[partition].s_partition_len;
-	if (first_block < 0 || first_block >= part_len)
+	if (first_block >= part_len)
 		goto out;
 
 	if (first_block + block_count > part_len)
@@ -297,7 +297,7 @@ static int udf_bitmap_new_block(struct super_block *sb,
 	mutex_lock(&sbi->s_alloc_mutex);
 
 repeat:
-	if (goal < 0 || goal >= sbi->s_partmaps[partition].s_partition_len)
+	if (goal >= sbi->s_partmaps[partition].s_partition_len)
 		goal = 0;
 
 	nr_groups = bitmap->s_nr_groups;
@@ -666,8 +666,7 @@ static int udf_table_prealloc_blocks(struct super_block *sb,
 	int8_t etype = -1;
 	struct udf_inode_info *iinfo;
 
-	if (first_block < 0 ||
-		first_block >= sbi->s_partmaps[partition].s_partition_len)
+	if (first_block >= sbi->s_partmaps[partition].s_partition_len)
 		return 0;
 
 	iinfo = UDF_I(table);
@@ -743,7 +742,7 @@ static int udf_table_new_block(struct super_block *sb,
 		return newblock;
 
 	mutex_lock(&sbi->s_alloc_mutex);
-	if (goal < 0 || goal >= sbi->s_partmaps[partition].s_partition_len)
+	if (goal >= sbi->s_partmaps[partition].s_partition_len)
 		goal = 0;
 
 	/* We search for the closest matching block to goal. If we find