This patch adds ACL supports to mqueue filesystem.
Based on Linux 3.0.4.

Signed-off-by: Zhou Peng <zhoupeng@nfs.iscas.ac.cn>

diff --git a/fs/Kconfig b/fs/Kconfig
index 19891aa..dbf0aca 100644
--- a/fs/Kconfig
+++ b/fs/Kconfig
@@ -151,6 +151,14 @@ config TMPFS_XATTR
 
 	  If unsure, say N.
 
+config MQUEUE_POSIX_ACL
+       bool "Mqueue POSIX Access Control Lists support"
+       depends on POSIX_MQUEUE
+       select GENERIC_ACL
+       help
+         Mqueue is a file system which is used to suport POSIX msg queue.
+	 Say y to get Access Control Lists support for mqueue file system.
+
 config HUGETLBFS
 	bool "HugeTLB file system support"
 	depends on X86 || IA64 || SPARC64 || (S390 && 64BIT) || \
diff --git a/ipc/mqueue.c b/ipc/mqueue.c
index 14fb6d6..e9d7ea9 100644
--- a/ipc/mqueue.c
+++ b/ipc/mqueue.c
@@ -10,6 +10,9 @@
  *
  * Audit:                   George Wilson           (ltcgcw@us.ibm.com)
  *
+ * ACL:
+ * Copyright (c) 2011       Zhou Peng               (ailvpeng25@gmail.com)
+ *
  * This file is released under the GPL.
  */
 
@@ -33,6 +36,9 @@
 #include <linux/pid.h>
 #include <linux/ipc_namespace.h>
 #include <linux/slab.h>
+#include <linux/xattr.h>
+#include <linux/posix_acl.h>
+#include <linux/generic_acl.h>
 
 #include <net/sock.h>
 #include "util.h"
@@ -76,6 +82,9 @@ struct mqueue_inode_info {
 };
 
 static const struct inode_operations mqueue_dir_inode_operations;
+#ifdef CONFIG_MQUEUE_POSIX_ACL
+static const struct inode_operations mqueue_inode_operations;
+#endif
 static const struct file_operations mqueue_file_operations;
 static const struct super_operations mqueue_super_ops;
 static void remove_notification(struct mqueue_inode_info *info);
@@ -84,6 +93,14 @@ static struct kmem_cache *mqueue_inode_cachep;
 
 static struct ctl_table_header * mq_sysctl_table;
 
+#ifdef CONFIG_MQUEUE_POSIX_ACL
+static const struct xattr_handler *mqueue_xattr_handlers[] = {
+	&generic_acl_access_handler,
+	&generic_acl_default_handler,
+	NULL
+};
+#endif
+
 static inline struct mqueue_inode_info *MQUEUE_I(struct inode *inode)
 {
 	return container_of(inode, struct mqueue_inode_info, vfs_inode);
@@ -122,12 +139,19 @@ static struct inode *mqueue_get_inode(struct super_block *sb,
 		inode->i_gid = current_fsgid();
 		inode->i_mtime = inode->i_ctime = inode->i_atime =
 				CURRENT_TIME;
+#ifdef CONFIG_MQUEUE_POSIX_ACL
+		cache_no_acl(inode);
+#endif
 
 		if (S_ISREG(mode)) {
 			struct mqueue_inode_info *info;
 			struct task_struct *p = current;
 			unsigned long mq_bytes, mq_msg_tblsz;
 
+#ifdef CONFIG_MQUEUE_POSIX_ACL			
+			inode->i_op = &mqueue_inode_operations;
+#endif
+
 			inode->i_fop = &mqueue_file_operations;
 			inode->i_size = FILENT_SIZE;
 			/* mqueue specific info */
@@ -192,6 +216,11 @@ static int mqueue_fill_super(struct super_block *sb, void *data, int silent)
 	sb->s_magic = MQUEUE_MAGIC;
 	sb->s_op = &mqueue_super_ops;
 
+#ifdef CONFIG_MQUEUE_POSIX_ACL
+	sb->s_xattr = mqueue_xattr_handlers;
+	sb->s_flags |= MS_POSIXACL;
+#endif
+
 	inode = mqueue_get_inode(sb, ns, S_IFDIR | S_ISVTX | S_IRWXUGO,
 				NULL);
 	if (!inode) {
@@ -322,6 +351,16 @@ static int mqueue_create(struct inode *dir, struct dentry *dentry,
 		goto out_unlock;
 	}
 
+#ifdef CONFIG_MQUEUE_POSIX_ACL
+	error = generic_acl_init(inode, dir);
+	if (error) {
+		iput(inode);
+		spin_lock(&mq_lock);
+		ipc_ns->mq_queues_count--;
+		goto out_unlock;
+	}
+#endif
+
 	put_ipc_ns(ipc_ns);
 	dir->i_size += DIRENT_SIZE;
 	dir->i_ctime = dir->i_mtime = dir->i_atime = CURRENT_TIME;
@@ -1217,10 +1256,46 @@ out:
 	return ret;
 }
 
+#ifdef CONFIG_MQUEUE_POSIX_ACL
+static int mqueue_setattr(struct dentry *dentry, struct iattr *attr)
+{
+	struct inode *inode = dentry->d_inode;
+	int error;
+
+	error = simple_setattr(dentry, attr);
+	if (error)
+		return error;
+
+	if (attr->ia_valid & ATTR_MODE)
+		error = generic_acl_chmod(inode);
+
+	return error;
+}
+#endif
+
 static const struct inode_operations mqueue_dir_inode_operations = {
 	.lookup = simple_lookup,
 	.create = mqueue_create,
 	.unlink = mqueue_unlink,
+#ifdef CONFIG_MQUEUE_POSIX_ACL
+	.setxattr    = generic_setxattr,
+	.getxattr    = generic_getxattr,
+	.listxattr   = generic_listxattr,
+	.removexattr = generic_removexattr,
+	.check_acl   = generic_check_acl,
+	.setattr     = mqueue_setattr,
+#endif
+};
+
+static const struct inode_operations mqueue_inode_operations = {
+#ifdef CONFIG_MQUEUE_POSIX_ACL
+	.setxattr    = generic_setxattr,
+	.getxattr    = generic_getxattr,
+	.listxattr   = generic_listxattr,
+	.removexattr = generic_removexattr,
+	.check_acl   = generic_check_acl,
+	.setattr     = mqueue_setattr,
+#endif
 };
 
 static const struct file_operations mqueue_file_operations = {