ext4: add interface to advertise ext4 features in sysfs

User-space should have the opportunity to check what features doest ext4
support in each particular copy. This adds easy interface by creating new
"features" directory in sys/fs/ext4/. In that directory files
advertising feature names can be created.

Add lazy_itable_init to the feature list.

Signed-off-by: Lukas Czerner <lczerner@redhat.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>

1 files changed, 10 insertions, 9 deletions

diff --git a/fs/ext4/ialloc.c b/fs/ext4/ialloc.c
index e428f23215c0..87d228aae6b0 100644
--- a/fs/ext4/ialloc.c
+++ b/fs/ext4/ialloc.c
@@ -1274,6 +1274,16 @@ extern int ext4_init_inode_table(struct super_block *sb, ext4_group_t group,
                             ext4_itable_unused_count(sb, gdp)),
                             sbi->s_inodes_per_block);
 
+        if ((used_blks < 0) || (used_blks > sbi->s_itb_per_group)) {
+                ext4_error(sb, "Something is wrong with group %u\n"
+                           "Used itable blocks: %d"
+                           "itable unused count: %u\n",
+                           group, used_blks,
+                           ext4_itable_unused_count(sb, gdp));
+                ret = 1;
+                goto out;
+        }
+
         blk = ext4_inode_table(sb, gdp) + used_blks;
         num = sbi->s_itb_per_group - used_blks;
 
@@ -1283,15 +1293,6 @@ extern int ext4_init_inode_table(struct super_block *sb, ext4_group_t group,
         if (ret)
                 goto err_out;
 
-        if (unlikely(num > EXT4_INODES_PER_GROUP(sb))) {
-                ext4_error(sb, "Something is wrong with group %u\n"
-                           "Used itable blocks: %d"
-                           "Itable blocks per group: %lu\n",
-                           group, used_blks, sbi->s_itb_per_group);
-                ret = 1;
-                goto err_out;
-        }
-
         /*
          * Skip zeroout if the inode table is full. But we set the ZEROED
          * flag anyway, because obviously, when it is full it does not need