5 #include <linux/fs.h>
12  * Replace the fs->{rootmnt,root} with {mnt,dentry}. Put the old values.
15 void set_fs_root(struct fs_struct *fs, const struct path *path)  in set_fs_root()  argument
20 	write_seqlock(&fs->seq);  in set_fs_root()
21 	old_root = fs->root;  in set_fs_root()
22 	fs->root = *path;  in set_fs_root()
23 	write_sequnlock(&fs->seq);  in set_fs_root()
29  * Replace the fs->{pwdmnt,pwd} with {mnt,dentry}. Put the old values.
32 void set_fs_pwd(struct fs_struct *fs, const struct path *path)  in set_fs_pwd()  argument
37 	write_seqlock(&fs->seq);  in set_fs_pwd()
38 	old_pwd = fs->pwd;  in set_fs_pwd()
39 	fs->pwd = *path;  in set_fs_pwd()
40 	write_sequnlock(&fs->seq);  in set_fs_pwd()
57 	struct fs_struct *fs;  in chroot_fs_refs()  local
63 		fs = p->fs;  in chroot_fs_refs()
64 		if (fs) {  in chroot_fs_refs()
66 			write_seqlock(&fs->seq);  in chroot_fs_refs()
67 			hits += replace_path(&fs->root, old_root, new_root);  in chroot_fs_refs()
68 			hits += replace_path(&fs->pwd, old_root, new_root);  in chroot_fs_refs()
73 			write_sequnlock(&fs->seq);  in chroot_fs_refs()
82 void free_fs_struct(struct fs_struct *fs)  in free_fs_struct()  argument
84 	path_put(&fs->root);  in free_fs_struct()
85 	path_put(&fs->pwd);  in free_fs_struct()
86 	kmem_cache_free(fs_cachep, fs);  in free_fs_struct()
91 	struct fs_struct *fs = tsk->fs;  in exit_fs()  local
93 	if (fs) {  in exit_fs()
96 		read_seqlock_excl(&fs->seq);  in exit_fs()
97 		tsk->fs = NULL;  in exit_fs()
98 		kill = !--fs->users;  in exit_fs()
99 		read_sequnlock_excl(&fs->seq);  in exit_fs()
102 			free_fs_struct(fs);  in exit_fs()
108 	struct fs_struct *fs = kmem_cache_alloc(fs_cachep, GFP_KERNEL);  in copy_fs_struct()  local
109 	/* We don't need to lock fs - think why ;-) */  in copy_fs_struct()
110 	if (fs) {  in copy_fs_struct()
111 		fs->users = 1;  in copy_fs_struct()
112 		fs->in_exec = 0;  in copy_fs_struct()
113 		seqlock_init(&fs->seq);  in copy_fs_struct()
114 		fs->umask = old->umask;  in copy_fs_struct()
117 		fs->root = old->root;  in copy_fs_struct()
118 		path_get(&fs->root);  in copy_fs_struct()
119 		fs->pwd = old->pwd;  in copy_fs_struct()
120 		path_get(&fs->pwd);  in copy_fs_struct()
123 	return fs;  in copy_fs_struct()
128 	struct fs_struct *fs = current->fs;  in unshare_fs_struct()  local
129 	struct fs_struct *new_fs = copy_fs_struct(fs);  in unshare_fs_struct()
136 	read_seqlock_excl(&fs->seq);  in unshare_fs_struct()
137 	kill = !--fs->users;  in unshare_fs_struct()
138 	current->fs = new_fs;  in unshare_fs_struct()
139 	read_sequnlock_excl(&fs->seq);  in unshare_fs_struct()
143 		free_fs_struct(fs);  in unshare_fs_struct()
151 	return current->fs->umask;  in current_umask()