hugetlbfs: allow the creation of files suitable for MAP_PRIVATE on the vfs internal...

[linux-flexiantxendom0-natty.git] / fs / hugetlbfs / inode.c

diff --git a/fs/hugetlbfs/inode.c b/fs/hugetlbfs/inode.c
index a93b885..06b7c26 100644 (file)
--- a/fs/hugetlbfs/inode.c
+++ b/fs/hugetlbfs/inode.c
@@ -507,6 +507,13 @@ static struct inode *hugetlbfs_get_inode(struct super_block *sb, uid_t uid,
                inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME;
                INIT_LIST_HEAD(&inode->i_mapping->private_list);
                info = HUGETLBFS_I(inode);
+               /*
+                * The policy is initialized here even if we are creating a
+                * private inode because initialization simply creates an
+                * an empty rb tree and calls spin_lock_init(), later when we
+                * call mpol_free_shared_policy() it will just return because
+                * the rb tree will still be empty.
+                */
                mpol_shared_policy_init(&info->policy, NULL);
                switch (mode & S_IFMT) {
                default:
@@ -931,13 +938,19 @@ static struct file_system_type hugetlbfs_fs_type = {
 
 static struct vfsmount *hugetlbfs_vfsmount;
 
-static int can_do_hugetlb_shm(void)
+static int can_do_hugetlb_shm(int creat_flags)
 {
-       return capable(CAP_IPC_LOCK) || in_group_p(sysctl_hugetlb_shm_group);
+       if (creat_flags != HUGETLB_SHMFS_INODE)
+               return 0;
+       if (capable(CAP_IPC_LOCK))
+               return 1;
+       if (in_group_p(sysctl_hugetlb_shm_group))
+               return 1;
+       return 0;
 }
 
 struct file *hugetlb_file_setup(const char *name, size_t size, int acctflag,
-                                               struct user_struct **user)
+                               struct user_struct **user, int creat_flags)
 {
        int error = -ENOMEM;
        struct file *file;
@@ -949,7 +962,7 @@ struct file *hugetlb_file_setup(const char *name, size_t size, int acctflag,
        if (!hugetlbfs_vfsmount)
                return ERR_PTR(-ENOENT);
 
-       if (!can_do_hugetlb_shm()) {
+       if (!can_do_hugetlb_shm(creat_flags)) {
                *user = current_user();
                if (user_shm_lock(size, *user)) {
                        WARN_ONCE(1,