4 files changed, 24 insertions, 41 deletions

diff --git a/fs/proc/base.c b/fs/proc/base.c
index beaa0ce3b82e..e0afd326b688 100644
--- a/fs/proc/base.c
+++ b/fs/proc/base.c
@@ -146,15 +146,22 @@ static unsigned int pid_entry_count_dirs(const struct pid_entry *entries,
 	return count;
 }
 
-static struct fs_struct *get_fs_struct(struct task_struct *task)
+static int get_fs_path(struct task_struct *task, struct path *path, bool root)
 {
 	struct fs_struct *fs;
+	int result = -ENOENT;
+
 	task_lock(task);
 	fs = task->fs;
-	if(fs)
-		atomic_inc(&fs->count);
+	if (fs) {
+		read_lock(&fs->lock);
+		*path = root ? fs->root : fs->pwd;
+		path_get(path);
+		read_unlock(&fs->lock);
+		result = 0;
+	}
 	task_unlock(task);
-	return fs;
+	return result;
 }
 
 static int get_nr_threads(struct task_struct *tsk)
@@ -172,42 +179,24 @@ static int get_nr_threads(struct task_struct *tsk)
 static int proc_cwd_link(struct inode *inode, struct path *path)
 {
 	struct task_struct *task = get_proc_task(inode);
-	struct fs_struct *fs = NULL;
 	int result = -ENOENT;
 
 	if (task) {
-		fs = get_fs_struct(task);
+		result = get_fs_path(task, path, 0);
 		put_task_struct(task);
 	}
-	if (fs) {
-		read_lock(&fs->lock);
-		*path = fs->pwd;
-		path_get(&fs->pwd);
-		read_unlock(&fs->lock);
-		result = 0;
-		put_fs_struct(fs);
-	}
 	return result;
 }
 
 static int proc_root_link(struct inode *inode, struct path *path)
 {
 	struct task_struct *task = get_proc_task(inode);
-	struct fs_struct *fs = NULL;
 	int result = -ENOENT;
 
 	if (task) {
-		fs = get_fs_struct(task);
+		result = get_fs_path(task, path, 1);
 		put_task_struct(task);
 	}
-	if (fs) {
-		read_lock(&fs->lock);
-		*path = fs->root;
-		path_get(&fs->root);
-		read_unlock(&fs->lock);
-		result = 0;
-		put_fs_struct(fs);
-	}
 	return result;
 }
 
@@ -596,7 +585,6 @@ static int mounts_open_common(struct inode *inode, struct file *file,
 	struct task_struct *task = get_proc_task(inode);
 	struct nsproxy *nsp;
 	struct mnt_namespace *ns = NULL;
-	struct fs_struct *fs = NULL;
 	struct path root;
 	struct proc_mounts *p;
 	int ret = -EINVAL;
@@ -610,22 +598,16 @@ static int mounts_open_common(struct inode *inode, struct file *file,
 				get_mnt_ns(ns);
 		}
 		rcu_read_unlock();
-		if (ns)
-			fs = get_fs_struct(task);
+		if (ns && get_fs_path(task, &root, 1) == 0)
+			ret = 0;
 		put_task_struct(task);
 	}
 
 	if (!ns)
 		goto err;
-	if (!fs)
+	if (ret)
 		goto err_put_ns;
 
-	read_lock(&fs->lock);
-	root = fs->root;
-	path_get(&root);
-	read_unlock(&fs->lock);
-	put_fs_struct(fs);
-
 	ret = -ENOMEM;
 	p = kmalloc(sizeof(struct proc_mounts), GFP_KERNEL);
 	if (!p)
@@ -1545,7 +1527,7 @@ static int pid_delete_dentry(struct dentry * dentry)
 	return !proc_pid(dentry->d_inode)->tasks[PIDTYPE_PID].first;
 }
 
-static struct dentry_operations pid_dentry_operations =
+static const struct dentry_operations pid_dentry_operations =
 {
 	.d_revalidate	= pid_revalidate,
 	.d_delete	= pid_delete_dentry,
@@ -1717,7 +1699,7 @@ static int tid_fd_revalidate(struct dentry *dentry, struct nameidata *nd)
 	return 0;
 }
 
-static struct dentry_operations tid_fd_dentry_operations =
+static const struct dentry_operations tid_fd_dentry_operations =
 {
 	.d_revalidate	= tid_fd_revalidate,
 	.d_delete	= pid_delete_dentry,
@@ -2339,7 +2321,7 @@ static int proc_base_revalidate(struct dentry *dentry, struct nameidata *nd)
 	return 0;
 }
 
-static struct dentry_operations proc_base_dentry_operations =
+static const struct dentry_operations proc_base_dentry_operations =
 {
 	.d_revalidate	= proc_base_revalidate,
 	.d_delete	= pid_delete_dentry,
diff --git a/fs/proc/generic.c b/fs/proc/generic.c
index db7fa5cab988..5d2989e9dcc1 100644
--- a/fs/proc/generic.c
+++ b/fs/proc/generic.c
@@ -363,7 +363,7 @@ static int proc_delete_dentry(struct dentry * dentry)
 	return 1;
 }
 
-static struct dentry_operations proc_dentry_operations =
+static const struct dentry_operations proc_dentry_operations =
 {
 	.d_delete	= proc_delete_dentry,
 };
diff --git a/fs/proc/proc_sysctl.c b/fs/proc/proc_sysctl.c
index 94fcfff6863a..9b1e4e9a16bf 100644
--- a/fs/proc/proc_sysctl.c
+++ b/fs/proc/proc_sysctl.c
@@ -7,7 +7,7 @@
 #include <linux/security.h>
 #include "internal.h"
 
-static struct dentry_operations proc_sys_dentry_operations;
+static const struct dentry_operations proc_sys_dentry_operations;
 static const struct file_operations proc_sys_file_operations;
 static const struct inode_operations proc_sys_inode_operations;
 static const struct file_operations proc_sys_dir_file_operations;
@@ -396,7 +396,7 @@ static int proc_sys_compare(struct dentry *dir, struct qstr *qstr,
 	return !sysctl_is_seen(PROC_I(dentry->d_inode)->sysctl);
 }
 
-static struct dentry_operations proc_sys_dentry_operations = {
+static const struct dentry_operations proc_sys_dentry_operations = {
 	.d_revalidate	= proc_sys_revalidate,
 	.d_delete	= proc_sys_delete,
 	.d_compare	= proc_sys_compare,
diff --git a/fs/proc/root.c b/fs/proc/root.c
index f6299a25594e..1e15a2b176e8 100644
--- a/fs/proc/root.c
+++ b/fs/proc/root.c
@@ -83,7 +83,8 @@ static int proc_get_sb(struct file_system_type *fs_type,
 		ns->proc_mnt = mnt;
 	}
 
-	return simple_set_mnt(mnt, sb);
+	simple_set_mnt(mnt, sb);
+	return 0;
 }
 
 static void proc_kill_sb(struct super_block *sb)