ocfs2: add mount option and Kconfig option for acl

This patch adds the Kconfig option "CONFIG_OCFS2_FS_POSIX_ACL"
and mount options "acl" to enable acls in Ocfs2.

Signed-off-by: Tiger Yang <tiger.yang@oracle.com>
Signed-off-by: Mark Fasheh <mfasheh@suse.com>

3 files changed, 44 insertions, 1 deletions

diff --git a/Documentation/filesystems/ocfs2.txt b/Documentation/filesystems/ocfs2.txt
index 67310fbbb7df..c2a0871280a0 100644
--- a/Documentation/filesystems/ocfs2.txt
+++ b/Documentation/filesystems/ocfs2.txt
@@ -31,7 +31,6 @@ Features which OCFS2 does not support yet:
         - quotas
         - Directory change notification (F_NOTIFY)
         - Distributed Caching (F_SETLEASE/F_GETLEASE/break_lease)
-        - POSIX ACLs
 
 Mount options
 =============
@@ -79,3 +78,5 @@ inode64			Indicates that Ocfs2 is allowed to create inodes at
                         bits of significance.
 user_xattr      (*)     Enables Extended User Attributes.
 nouser_xattr            Disables Extended User Attributes.
+acl                     Enables POSIX Access Control Lists support.
+noacl           (*)     Disables POSIX Access Control Lists support.
diff --git a/fs/Kconfig b/fs/Kconfig
index ff0e81980207..e8a47f74a839 100644
--- a/fs/Kconfig
+++ b/fs/Kconfig
@@ -268,6 +268,15 @@ config OCFS2_COMPAT_JBD
           is backwards compatible with JBD.  It is safe to say N here.
           However, if you really want to use the original JBD, say Y here.
 
+config OCFS2_FS_POSIX_ACL
+        bool "OCFS2 POSIX Access Control Lists"
+        depends on OCFS2_FS
+        select FS_POSIX_ACL
+        default n
+        help
+          Posix Access Control Lists (ACLs) support permissions for users and
+          groups beyond the owner/group/world scheme.
+
 endif # BLOCK
 
 source "fs/notify/Kconfig"
diff --git a/fs/ocfs2/super.c b/fs/ocfs2/super.c
index 304b63ac78cf..9e7accc68b4b 100644
--- a/fs/ocfs2/super.c
+++ b/fs/ocfs2/super.c
@@ -158,6 +158,8 @@ enum {
         Opt_user_xattr,
         Opt_nouser_xattr,
         Opt_inode64,
+        Opt_acl,
+        Opt_noacl,
         Opt_err,
 };
 
@@ -180,6 +182,8 @@ static const match_table_t tokens = {
         {Opt_user_xattr, "user_xattr"},
         {Opt_nouser_xattr, "nouser_xattr"},
         {Opt_inode64, "inode64"},
+        {Opt_acl, "acl"},
+        {Opt_noacl, "noacl"},
         {Opt_err, NULL}
 };
 
@@ -466,6 +470,8 @@ unlock_osb:
         if (!ret) {
                 /* Only save off the new mount options in case of a successful
                  * remount. */
+                if (!(osb->s_feature_incompat & OCFS2_FEATURE_INCOMPAT_XATTR))
+                        parsed_options.mount_opt &= ~OCFS2_MOUNT_POSIX_ACL;
                 osb->s_mount_opt = parsed_options.mount_opt;
                 osb->s_atime_quantum = parsed_options.atime_quantum;
                 osb->preferred_slot = parsed_options.slot;
@@ -651,6 +657,10 @@ static int ocfs2_fill_super(struct super_block *sb, void *data, int silent)
         }
         brelse(bh);
         bh = NULL;
+
+        if (!(osb->s_feature_incompat & OCFS2_FEATURE_INCOMPAT_XATTR))
+                parsed_options.mount_opt &= ~OCFS2_MOUNT_POSIX_ACL;
+
         osb->s_mount_opt = parsed_options.mount_opt;
         osb->s_atime_quantum = parsed_options.atime_quantum;
         osb->preferred_slot = parsed_options.slot;
@@ -664,6 +674,9 @@ static int ocfs2_fill_super(struct super_block *sb, void *data, int silent)
 
         sb->s_magic = OCFS2_SUPER_MAGIC;
 
+        sb->s_flags = (sb->s_flags & ~MS_POSIXACL) |
+                ((osb->s_mount_opt & OCFS2_MOUNT_POSIX_ACL) ? MS_POSIXACL : 0);
+
         /* Hard readonly mode only if: bdev_read_only, MS_RDONLY,
          * heartbeat=none */
         if (bdev_read_only(sb->s_bdev)) {
@@ -945,6 +958,19 @@ static int ocfs2_parse_options(struct super_block *sb,
                 case Opt_inode64:
                         mopt->mount_opt |= OCFS2_MOUNT_INODE64;
                         break;
+#ifdef CONFIG_OCFS2_FS_POSIX_ACL
+                case Opt_acl:
+                        mopt->mount_opt |= OCFS2_MOUNT_POSIX_ACL;
+                        break;
+                case Opt_noacl:
+                        mopt->mount_opt &= ~OCFS2_MOUNT_POSIX_ACL;
+                        break;
+#else
+                case Opt_acl:
+                case Opt_noacl:
+                        printk(KERN_INFO "ocfs2 (no)acl options not supported\n");
+                        break;
+#endif
                 default:
                         mlog(ML_ERROR,
                              "Unrecognized mount option \"%s\" "
@@ -1017,6 +1043,13 @@ static int ocfs2_show_options(struct seq_file *s, struct vfsmount *mnt)
         if (opts & OCFS2_MOUNT_INODE64)
                 seq_printf(s, ",inode64");
 
+#ifdef CONFIG_OCFS2_FS_POSIX_ACL
+        if (opts & OCFS2_MOUNT_POSIX_ACL)
+                seq_printf(s, ",acl");
+        else
+                seq_printf(s, ",noacl");
+#endif
+
         return 0;
 }