mke2fs: Add check to make sure inode_size * num_inodes isn't too big

A quick patch to sanity check the inode ratio vs the inode size.  In
some cases Lustre users have tried specifying an inode size of 4096
bytes, while keeping an inode ratio of one inode per 4096 bytes.  I'm
sure more people will do this now that large inodes are available in
ext4 and documented in e2fsprogs.

Signed-off-by: Andreas Dilger <adilger@clusterfs.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>

diff --git a/misc/ChangeLog b/misc/ChangeLog
index 4a96f75..3b57d0c 100644 (file)
--- a/misc/ChangeLog
+++ b/misc/ChangeLog
@@ -1,3 +1,8 @@
+2007-05-22  Theodore Tso  <tytso@mit.edu>
+
+       * mke2fs.c (PRS): Add sanity check if the inode size * inode count
+               is bigger than the filesystem size.     
+
 2007-05-18  Theodore Tso  <tytso@mit.edu>
 
        * mke2fs.c (main): Save the raid stride to the superblock

diff --git a/misc/mke2fs.c b/misc/mke2fs.c
index 0a37137..737e3da 100644 (file)
--- a/misc/mke2fs.c
+++ b/misc/mke2fs.c
@@ -1489,6 +1489,20 @@ static void PRS(int argc, char *argv[])
                ((__u64) fs_param.s_blocks_count * blocksize)
                        / inode_ratio;
 
+       if ((((long long)fs_param.s_inodes_count) *
+            (inode_size ? inode_size : EXT2_GOOD_OLD_INODE_SIZE)) >=
+           (((long long)fs_param.s_blocks_count) * 
+            EXT2_BLOCK_SIZE(&fs_param))) {
+               com_err(program_name, 0, _("inode_size (%u) * inodes_count "
+                                         "(%u) too big for a\n\t"
+                                         "filesystem with %lu blocks, "
+                                         "specify higher inode_ratio (-i)\n\t"
+                                         "or lower inode count (-N).\n"),
+                       inode_size ? inode_size : EXT2_GOOD_OLD_INODE_SIZE,
+                       fs_param.s_inodes_count, fs_param.s_blocks_count);
+               exit(1);
+       }
+
        /*
         * Calculate number of blocks to reserve
         */