diff options
| -rw-r--r-- | 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 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; } |