lkml.org 
[lkml]   [2008]   [Jan]   [21]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH 16/49] ext2: Fix the max file size for ext2 file system.
Date
From: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>

The max file size for ext2 file system is now calculated
with hardcoded 4K block size. The patch fixes it to be
calculated with the right block size.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
---
fs/ext2/super.c | 32 ++++++++++++++++++++++++++++----
1 files changed, 28 insertions(+), 4 deletions(-)
diff --git a/fs/ext2/super.c b/fs/ext2/super.c
index 154e25f..6abaf75 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;
}

--
1.5.4.rc3.31.g1271-dirty


\
 
 \ /
  Last update: 2008-01-22 04:13    [from the cache]
©2003-2011 Jasper Spaans