[JFFS2][XATTR] XATTR support on JFFS2 (version. 5)

This attached patches provide xattr support including POSIX-ACL and
SELinux support on JFFS2 (version.5).

There are some significant differences from previous version posted
at last December.
The biggest change is addition of EBS(Erase Block Summary) support.
Currently, both kernel and usermode utility (sumtool) can recognize
xattr nodes which have JFFS2_NODETYPE_XATTR/_XREF nodetype.

In addition, some bugs are fixed.
- A potential race condition was fixed.
- Unexpected fail when updating a xattr by same name/value pair was fixed.
- A bug when removing xattr name/value pair was fixed.

The fundamental structures (such as using two new nodetypes and exclusion
mechanism by rwsem) are unchanged. But most of implementation were reviewed
and updated if necessary.
Espacially, we had to change several internal implementations related to
load_xattr_datum() to avoid a potential race condition.

[1/2] xattr_on_jffs2.kernel.version-5.patch
[2/2] xattr_on_jffs2.utils.version-5.patch

Signed-off-by: KaiGai Kohei <kaigai@ak.jp.nec.com>
Signed-off-by: David Woodhouse <dwmw2@infradead.org>

1 files changed, 5 insertions, 1 deletions

diff --git a/fs/jffs2/super.c b/fs/jffs2/super.c
index ffd8e84b22cc..c8b539ee7d80 100644
--- a/fs/jffs2/super.c
+++ b/fs/jffs2/super.c
@@ -151,7 +151,10 @@ static struct super_block *jffs2_get_sb_mtd(struct file_system_type *fs_type,
 
         sb->s_op = &jffs2_super_operations;
         sb->s_flags = flags | MS_NOATIME;
-
+        sb->s_xattr = jffs2_xattr_handlers;
+#ifdef CONFIG_JFFS2_FS_POSIX_ACL
+        sb->s_flags |= MS_POSIXACL;
+#endif
         ret = jffs2_do_fill_super(sb, data, flags & MS_SILENT ? 1 : 0);
 
         if (ret) {
@@ -293,6 +296,7 @@ static void jffs2_put_super (struct super_block *sb)
                 kfree(c->blocks);
         jffs2_flash_cleanup(c);
         kfree(c->inocache_list);
+        jffs2_clear_xattr_subsystem(c);
         if (c->mtd->sync)
                 c->mtd->sync(c->mtd);