Merge branch 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4

* 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: (50 commits)
  jbd2: sparse pointer use of zero as null
  jbd2: Use round-jiffies() function for the "5 second" ext4/jbd2 wakeup
  jbd2: Mark jbd2 slabs as SLAB_TEMPORARY
  jbd2: add lockdep support
  ext4: Use the ext4_ext_actual_len() helper function
  ext4: fix uniniatilized extent splitting error
  ext4: Check for return value from sb_set_blocksize
  ext4: Add stripe= option to /proc/mounts
  ext4: Enable the multiblock allocator by default
  ext4: Add multi block allocator for ext4
  ext4: Add new functions for searching extent tree
  ext4: Add ext4_find_next_bit()
  ext4: fix up EXT4FS_DEBUG builds
  ext4: Fix ext4_show_options to show the correct mount options.
  ext4: Add EXT4_IOC_MIGRATE ioctl
  ext4: Add inode version support in ext4
  vfs: Add 64 bit i_version support
  ext4: Add the journal checksum feature
  jbd2: jbd2 stats through procfs
  ext4: Take read lock during overwrite case.
  ...

1 files changed, 28 insertions, 4 deletions

diff --git a/fs/ext2/super.c b/fs/ext2/super.c
index 154e25f13d77..6abaf75163f0 100644
--- a/fs/ext2/super.c
+++ b/fs/ext2/super.c
@@ -680,11 +680,31 @@ static int ext2_check_descriptors (struct super_block * sb)
 static loff_t ext2_max_size(int bits)
 {
 	loff_t res = EXT2_NDIR_BLOCKS;
-	/* This constant is calculated to be the largest file size for a
-	 * dense, 4k-blocksize file such that the total number of
+	int meta_blocks;
+	loff_t upper_limit;
+
+	/* This is calculated to be the largest file size for a
+	 * dense, file such that the total number of
 	 * sectors in the file, including data and all indirect blocks,
-	 * does not exceed 2^32. */
-	const loff_t upper_limit = 0x1ff7fffd000LL;
+	 * does not exceed 2^32 -1
+	 * __u32 i_blocks representing the total number of
+	 * 512 bytes blocks of the file
+	 */
+	upper_limit = (1LL << 32) - 1;
+
+	/* total blocks in file system block size */
+	upper_limit >>= (bits - 9);
+
+
+	/* indirect blocks */
+	meta_blocks = 1;
+	/* double indirect blocks */
+	meta_blocks += 1 + (1LL << (bits-2));
+	/* tripple indirect blocks */
+	meta_blocks += 1 + (1LL << (bits-2)) + (1LL << (2*(bits-2)));
+
+	upper_limit -= meta_blocks;
+	upper_limit <<= bits;
 
 	res += 1LL << (bits-2);
 	res += 1LL << (2*(bits-2));
@@ -692,6 +712,10 @@ static loff_t ext2_max_size(int bits)
 	res <<= bits;
 	if (res > upper_limit)
 		res = upper_limit;
+
+	if (res > MAX_LFS_FILESIZE)
+		res = MAX_LFS_FILESIZE;
+
 	return res;
 }