diff options
Diffstat (limited to 'fs/autofs4')
| -rw-r--r-- | fs/autofs4/autofs_i.h | 183 | ||||
| -rw-r--r-- | fs/autofs4/dev-ioctl.c | 96 | ||||
| -rw-r--r-- | fs/autofs4/expire.c | 226 | ||||
| -rw-r--r-- | fs/autofs4/init.c | 7 | ||||
| -rw-r--r-- | fs/autofs4/inode.c | 217 | ||||
| -rw-r--r-- | fs/autofs4/root.c | 809 | ||||
| -rw-r--r-- | fs/autofs4/symlink.c | 5 | ||||
| -rw-r--r-- | fs/autofs4/waitq.c | 109 | 
8 files changed, 816 insertions, 836 deletions
diff --git a/fs/autofs4/autofs_i.h b/fs/autofs4/autofs_i.h index 3d283abf67d..acf32054edd 100644 --- a/fs/autofs4/autofs_i.h +++ b/fs/autofs4/autofs_i.h @@ -16,6 +16,7 @@  #include <linux/auto_fs4.h>  #include <linux/auto_dev-ioctl.h>  #include <linux/mutex.h> +#include <linux/spinlock.h>  #include <linux/list.h>  /* This is the range of ioctl() numbers we claim as ours */ @@ -38,27 +39,17 @@  /* #define DEBUG */ -#ifdef DEBUG -#define DPRINTK(fmt, args...)				\ -do {							\ -	printk(KERN_DEBUG "pid %d: %s: " fmt "\n",	\ -		current->pid, __func__, ##args);	\ -} while (0) -#else -#define DPRINTK(fmt, args...) do {} while (0) -#endif - -#define AUTOFS_WARN(fmt, args...)			\ -do {							\ +#define DPRINTK(fmt, ...)				\ +	pr_debug("pid %d: %s: " fmt "\n",		\ +		current->pid, __func__, ##__VA_ARGS__) + +#define AUTOFS_WARN(fmt, ...)				\  	printk(KERN_WARNING "pid %d: %s: " fmt "\n",	\ -		current->pid, __func__, ##args);	\ -} while (0) +		current->pid, __func__, ##__VA_ARGS__) -#define AUTOFS_ERROR(fmt, args...)			\ -do {							\ +#define AUTOFS_ERROR(fmt, ...)				\  	printk(KERN_ERR "pid %d: %s: " fmt "\n",	\ -		current->pid, __func__, ##args);	\ -} while (0) +		current->pid, __func__, ##__VA_ARGS__)  /* Unified info structure.  This is pointed to by both the dentry and     inode structures.  Each file in the filesystem has an instance of this @@ -83,20 +74,11 @@ struct autofs_info {  	unsigned long last_used;  	atomic_t count; -	uid_t uid; -	gid_t gid; - -	mode_t	mode; -	size_t	size; - -	void (*free)(struct autofs_info *); -	union { -		const char *symlink; -	} u; +	kuid_t uid; +	kgid_t gid;  };  #define AUTOFS_INF_EXPIRING	(1<<0) /* dentry is in the process of expiring */ -#define AUTOFS_INF_MOUNTPOINT	(1<<1) /* mountpoint status for direct expire */  #define AUTOFS_INF_PENDING	(1<<2) /* dentry pending mount */  struct autofs_wait_queue { @@ -107,8 +89,8 @@ struct autofs_wait_queue {  	struct qstr name;  	u32 dev;  	u64 ino; -	uid_t uid; -	gid_t gid; +	kuid_t uid; +	kgid_t gid;  	pid_t pid;  	pid_t tgid;  	/* This is for status reporting upon return */ @@ -122,7 +104,7 @@ struct autofs_sb_info {  	u32 magic;  	int pipefd;  	struct file *pipe; -	pid_t oz_pgrp; +	struct pid *oz_pgrp;  	int catatonic;  	int version;  	int sub_version; @@ -134,11 +116,13 @@ struct autofs_sb_info {  	int needs_reghost;  	struct super_block *sb;  	struct mutex wq_mutex; +	struct mutex pipe_mutex;  	spinlock_t fs_lock;  	struct autofs_wait_queue *queues; /* Wait queue pointer */  	spinlock_t lookup_lock;  	struct list_head active_list;  	struct list_head expiring_list; +	struct rcu_head rcu;  };  static inline struct autofs_sb_info *autofs4_sbi(struct super_block *sb) @@ -156,7 +140,7 @@ static inline struct autofs_info *autofs4_dentry_ino(struct dentry *dentry)     filesystem without "magic".) */  static inline int autofs4_oz_mode(struct autofs_sb_info *sbi) { -	return sbi->catatonic || task_pgrp_nr(current) == sbi->oz_pgrp; +	return sbi->catatonic || task_pgrp(current) == sbi->oz_pgrp;  }  /* Does a dentry have some pending activity? */ @@ -173,14 +157,7 @@ static inline int autofs4_ispending(struct dentry *dentry)  	return 0;  } -static inline void autofs4_copy_atime(struct file *src, struct file *dst) -{ -	dst->f_path.dentry->d_inode->i_atime = -		src->f_path.dentry->d_inode->i_atime; -	return; -} - -struct inode *autofs4_get_inode(struct super_block *, struct autofs_info *); +struct inode *autofs4_get_inode(struct super_block *, umode_t);  void autofs4_free_ino(struct autofs_info *);  /* Expiration */ @@ -209,16 +186,100 @@ void autofs_dev_ioctl_exit(void);  extern const struct inode_operations autofs4_symlink_inode_operations;  extern const struct inode_operations autofs4_dir_inode_operations; -extern const struct inode_operations autofs4_root_inode_operations; -extern const struct inode_operations autofs4_indirect_root_inode_operations; -extern const struct inode_operations autofs4_direct_root_inode_operations;  extern const struct file_operations autofs4_dir_operations;  extern const struct file_operations autofs4_root_operations; +extern const struct dentry_operations autofs4_dentry_operations; + +/* VFS automount flags management functions */ + +static inline void __managed_dentry_set_automount(struct dentry *dentry) +{ +	dentry->d_flags |= DCACHE_NEED_AUTOMOUNT; +} + +static inline void managed_dentry_set_automount(struct dentry *dentry) +{ +	spin_lock(&dentry->d_lock); +	__managed_dentry_set_automount(dentry); +	spin_unlock(&dentry->d_lock); +} + +static inline void __managed_dentry_clear_automount(struct dentry *dentry) +{ +	dentry->d_flags &= ~DCACHE_NEED_AUTOMOUNT; +} + +static inline void managed_dentry_clear_automount(struct dentry *dentry) +{ +	spin_lock(&dentry->d_lock); +	__managed_dentry_clear_automount(dentry); +	spin_unlock(&dentry->d_lock); +} + +static inline void __managed_dentry_set_transit(struct dentry *dentry) +{ +	dentry->d_flags |= DCACHE_MANAGE_TRANSIT; +} + +static inline void managed_dentry_set_transit(struct dentry *dentry) +{ +	spin_lock(&dentry->d_lock); +	__managed_dentry_set_transit(dentry); +	spin_unlock(&dentry->d_lock); +} + +static inline void __managed_dentry_clear_transit(struct dentry *dentry) +{ +	dentry->d_flags &= ~DCACHE_MANAGE_TRANSIT; +} + +static inline void managed_dentry_clear_transit(struct dentry *dentry) +{ +	spin_lock(&dentry->d_lock); +	__managed_dentry_clear_transit(dentry); +	spin_unlock(&dentry->d_lock); +} + +static inline void __managed_dentry_set_managed(struct dentry *dentry) +{ +	dentry->d_flags |= (DCACHE_NEED_AUTOMOUNT|DCACHE_MANAGE_TRANSIT); +} + +static inline void managed_dentry_set_managed(struct dentry *dentry) +{ +	spin_lock(&dentry->d_lock); +	__managed_dentry_set_managed(dentry); +	spin_unlock(&dentry->d_lock); +} + +static inline void __managed_dentry_clear_managed(struct dentry *dentry) +{ +	dentry->d_flags &= ~(DCACHE_NEED_AUTOMOUNT|DCACHE_MANAGE_TRANSIT); +} + +static inline void managed_dentry_clear_managed(struct dentry *dentry) +{ +	spin_lock(&dentry->d_lock); +	__managed_dentry_clear_managed(dentry); +	spin_unlock(&dentry->d_lock); +}  /* Initializing function */  int autofs4_fill_super(struct super_block *, void *, int); -struct autofs_info *autofs4_init_ino(struct autofs_info *, struct autofs_sb_info *sbi, mode_t mode); +struct autofs_info *autofs4_new_ino(struct autofs_sb_info *); +void autofs4_clean_ino(struct autofs_info *); + +static inline int autofs_prepare_pipe(struct file *pipe) +{ +	if (!pipe->f_op->write) +		return -EINVAL; +	if (!S_ISFIFO(file_inode(pipe)->i_mode)) +		return -EINVAL; +	/* We want a packet pipe */ +	pipe->f_flags |= O_DIRECT; +	return 0; +}  /* Queue management functions */ @@ -226,19 +287,6 @@ int autofs4_wait(struct autofs_sb_info *,struct dentry *, enum autofs_notify);  int autofs4_wait_release(struct autofs_sb_info *,autofs_wqt_t,int);  void autofs4_catatonic_mode(struct autofs_sb_info *); -static inline int autofs4_follow_mount(struct path *path) -{ -	int res = 0; - -	while (d_mountpoint(path->dentry)) { -		int followed = follow_down(path); -		if (!followed) -			break; -		res = 1; -	} -	return res; -} -  static inline u32 autofs4_get_dev(struct autofs_sb_info *sbi)  {  	return new_encode_dev(sbi->sb->s_dev); @@ -254,17 +302,15 @@ static inline int simple_positive(struct dentry *dentry)  	return dentry->d_inode && !d_unhashed(dentry);  } -static inline int __simple_empty(struct dentry *dentry) +static inline void __autofs4_add_expiring(struct dentry *dentry)  { -	struct dentry *child; -	int ret = 0; - -	list_for_each_entry(child, &dentry->d_subdirs, d_u.d_child) -		if (simple_positive(child)) -			goto out; -	ret = 1; -out: -	return ret; +	struct autofs_sb_info *sbi = autofs4_sbi(dentry->d_sb); +	struct autofs_info *ino = autofs4_dentry_ino(dentry); +	if (ino) { +		if (list_empty(&ino->expiring)) +			list_add(&ino->expiring, &sbi->expiring_list); +	} +	return;  }  static inline void autofs4_add_expiring(struct dentry *dentry) @@ -293,5 +339,4 @@ static inline void autofs4_del_expiring(struct dentry *dentry)  	return;  } -void autofs4_dentry_release(struct dentry *);  extern void autofs4_kill_sb(struct super_block *); diff --git a/fs/autofs4/dev-ioctl.c b/fs/autofs4/dev-ioctl.c index eff9a419469..5b570b6efa2 100644 --- a/fs/autofs4/dev-ioctl.c +++ b/fs/autofs4/dev-ioctl.c @@ -103,6 +103,9 @@ static struct autofs_dev_ioctl *copy_dev_ioctl(struct autofs_dev_ioctl __user *i  	if (tmp.size < sizeof(tmp))  		return ERR_PTR(-EINVAL); +	if (tmp.size > (PATH_MAX + sizeof(tmp))) +		return ERR_PTR(-ENAMETOOLONG); +  	return memdup_user(in, tmp.size);  } @@ -159,7 +162,7 @@ static struct autofs_sb_info *autofs_dev_ioctl_sbi(struct file *f)  	struct inode *inode;  	if (f) { -		inode = f->f_path.dentry->d_inode; +		inode = file_inode(f);  		sbi = autofs4_sbi(inode->i_sb);  	}  	return sbi; @@ -183,24 +186,24 @@ static int autofs_dev_ioctl_protosubver(struct file *fp,  	return 0;  } +/* Find the topmost mount satisfying test() */  static int find_autofs_mount(const char *pathname,  			     struct path *res,  			     int test(struct path *path, void *data),  			     void *data)  {  	struct path path; -	int err = kern_path(pathname, 0, &path); +	int err = kern_path_mountpoint(AT_FDCWD, pathname, &path, 0);  	if (err)  		return err;  	err = -ENOENT;  	while (path.dentry == path.mnt->mnt_root) { -		if (path.mnt->mnt_sb->s_magic == AUTOFS_SUPER_MAGIC) { +		if (path.dentry->d_sb->s_magic == AUTOFS_SUPER_MAGIC) {  			if (test(&path, data)) {  				path_get(&path); -				if (!err) /* already found some */ -					path_put(res);  				*res = path;  				err = 0; +				break;  			}  		}  		if (!follow_up(&path)) @@ -212,7 +215,7 @@ static int find_autofs_mount(const char *pathname,  static int test_by_dev(struct path *path, void *p)  { -	return path->mnt->mnt_sb->s_dev == *(dev_t *)p; +	return path->dentry->d_sb->s_dev == *(dev_t *)p;  }  static int test_by_type(struct path *path, void *p) @@ -221,20 +224,6 @@ static int test_by_type(struct path *path, void *p)  	return ino && ino->sbi->type & *(unsigned *)p;  } -static void autofs_dev_ioctl_fd_install(unsigned int fd, struct file *file) -{ -	struct files_struct *files = current->files; -	struct fdtable *fdt; - -	spin_lock(&files->file_lock); -	fdt = files_fdtable(files); -	BUG_ON(fdt->fd[fd] != NULL); -	rcu_assign_pointer(fdt->fd[fd], file); -	FD_SET(fd, fdt->close_on_exec); -	spin_unlock(&files->file_lock); -} - -  /*   * Open a file descriptor on the autofs mount point corresponding   * to the given path and device number (aka. new_encode_dev(sb->s_dev)). @@ -243,7 +232,7 @@ static int autofs_dev_ioctl_open_mountpoint(const char *name, dev_t devid)  {  	int err, fd; -	fd = get_unused_fd(); +	fd = get_unused_fd_flags(O_CLOEXEC);  	if (likely(fd >= 0)) {  		struct file *filp;  		struct path path; @@ -257,14 +246,14 @@ static int autofs_dev_ioctl_open_mountpoint(const char *name, dev_t devid)  		 * corresponding to the autofs fs we want to open.  		 */ -		filp = dentry_open(path.dentry, path.mnt, O_RDONLY, -				   current_cred()); +		filp = dentry_open(&path, O_RDONLY, current_cred()); +		path_put(&path);  		if (IS_ERR(filp)) {  			err = PTR_ERR(filp);  			goto out;  		} -		autofs_dev_ioctl_fd_install(fd, filp); +		fd_install(fd, filp);  	}  	return fd; @@ -360,6 +349,7 @@ static int autofs_dev_ioctl_setpipefd(struct file *fp,  {  	int pipefd;  	int err = 0; +	struct pid *new_pid = NULL;  	if (param->setpipefd.pipefd == -1)  		return -EINVAL; @@ -371,18 +361,33 @@ static int autofs_dev_ioctl_setpipefd(struct file *fp,  		mutex_unlock(&sbi->wq_mutex);  		return -EBUSY;  	} else { -		struct file *pipe = fget(pipefd); -		if (!pipe->f_op || !pipe->f_op->write) { +		struct file *pipe; + +		new_pid = get_task_pid(current, PIDTYPE_PGID); + +		if (ns_of_pid(new_pid) != ns_of_pid(sbi->oz_pgrp)) { +			AUTOFS_WARN("Not allowed to change PID namespace"); +			err = -EINVAL; +			goto out; +		} + +		pipe = fget(pipefd); +		if (!pipe) { +			err = -EBADF; +			goto out; +		} +		if (autofs_prepare_pipe(pipe) < 0) {  			err = -EPIPE;  			fput(pipe);  			goto out;  		} -		sbi->oz_pgrp = task_pgrp_nr(current); +		swap(sbi->oz_pgrp, new_pid);  		sbi->pipefd = pipefd;  		sbi->pipe = pipe;  		sbi->catatonic = 0;  	}  out: +	put_pid(new_pid);  	mutex_unlock(&sbi->wq_mutex);  	return err;  } @@ -447,8 +452,8 @@ static int autofs_dev_ioctl_requester(struct file *fp,  		err = 0;  		autofs4_expire_wait(path.dentry);  		spin_lock(&sbi->fs_lock); -		param->requester.uid = ino->uid; -		param->requester.gid = ino->gid; +		param->requester.uid = from_kuid_munged(current_user_ns(), ino->uid); +		param->requester.gid = from_kgid_munged(current_user_ns(), ino->gid);  		spin_unlock(&sbi->fs_lock);  	}  	path_put(&path); @@ -496,12 +501,11 @@ static int autofs_dev_ioctl_askumount(struct file *fp,   * mount if there is one or 0 if it isn't a mountpoint.   *   * If we aren't supplied with a file descriptor then we - * lookup the nameidata of the path and check if it is the - * root of a mount. If a type is given we are looking for - * a particular autofs mount and if we don't find a match - * we return fail. If the located nameidata path is the - * root of a mount we return 1 along with the super magic - * of the mount or 0 otherwise. + * lookup the path and check if it is the root of a mount. + * If a type is given we are looking for a particular autofs + * mount and if we don't find a match we return fail. If the + * located path is the root of a mount we return 1 along with + * the super magic of the mount or 0 otherwise.   *   * In both cases the the device number (as returned by   * new_encode_dev()) is also returned. @@ -529,16 +533,18 @@ static int autofs_dev_ioctl_ismountpoint(struct file *fp,  	if (!fp || param->ioctlfd == -1) {  		if (autofs_type_any(type)) -			err = kern_path(name, LOOKUP_FOLLOW, &path); +			err = kern_path_mountpoint(AT_FDCWD, +						   name, &path, LOOKUP_FOLLOW);  		else -			err = find_autofs_mount(name, &path, test_by_type, &type); +			err = find_autofs_mount(name, &path, +						test_by_type, &type);  		if (err)  			goto out; -		devid = new_encode_dev(path.mnt->mnt_sb->s_dev); +		devid = new_encode_dev(path.dentry->d_sb->s_dev);  		err = 0;  		if (path.mnt->mnt_root == path.dentry) {  			err = 1; -			magic = path.mnt->mnt_sb->s_magic; +			magic = path.dentry->d_sb->s_magic;  		}  	} else {  		dev_t dev = sbi->sb->s_dev; @@ -551,8 +557,8 @@ static int autofs_dev_ioctl_ismountpoint(struct file *fp,  		err = have_submounts(path.dentry); -		if (follow_down(&path)) -			magic = path.mnt->mnt_sb->s_magic; +		if (follow_down_one(&path)) +			magic = path.dentry->d_sb->s_magic;  	}  	param->ismountpoint.out.devid = devid; @@ -667,12 +673,6 @@ static int _autofs_dev_ioctl(unsigned int command, struct autofs_dev_ioctl __use  			goto out;  		} -		if (!fp->f_op) { -			err = -ENOTTY; -			fput(fp); -			goto out; -		} -  		sbi = autofs_dev_ioctl_sbi(fp);  		if (!sbi || sbi->magic != AUTOFS_SBI_MAGIC) {  			err = -EINVAL; @@ -737,7 +737,7 @@ MODULE_ALIAS_MISCDEV(AUTOFS_MINOR);  MODULE_ALIAS("devname:autofs");  /* Register/deregister misc character device */ -int autofs_dev_ioctl_init(void) +int __init autofs_dev_ioctl_init(void)  {  	int r; diff --git a/fs/autofs4/expire.c b/fs/autofs4/expire.c index a796c9417fb..394e90b02c5 100644 --- a/fs/autofs4/expire.c +++ b/fs/autofs4/expire.c @@ -26,10 +26,6 @@ static inline int autofs4_can_expire(struct dentry *dentry,  	if (ino == NULL)  		return 0; -	/* No point expiring a pending mount */ -	if (ino->flags & AUTOFS_INF_PENDING) -		return 0; -  	if (!do_now) {  		/* Too young to die */  		if (!timeout || time_after(ino->last_used + timeout, now)) @@ -56,7 +52,7 @@ static int autofs4_mount_busy(struct vfsmount *mnt, struct dentry *dentry)  	path_get(&path); -	if (!follow_down(&path)) +	if (!follow_down_one(&path))  		goto done;  	if (is_autofs4_dentry(path.dentry)) { @@ -65,15 +61,6 @@ static int autofs4_mount_busy(struct vfsmount *mnt, struct dentry *dentry)  		/* This is an autofs submount, we can't expire it */  		if (autofs_type_indirect(sbi->type))  			goto done; - -		/* -		 * Otherwise it's an offset mount and we need to check -		 * if we can umount its mount, if there is one. -		 */ -		if (!d_mountpoint(path.dentry)) { -			status = 0; -			goto done; -		}  	}  	/* Update the expiry counter if fs is busy */ @@ -91,24 +78,113 @@ done:  }  /* - * Calculate next entry in top down tree traversal. - * From next_mnt in namespace.c - elegant. + * Calculate and dget next entry in the subdirs list under root.   */ -static struct dentry *next_dentry(struct dentry *p, struct dentry *root) +static struct dentry *get_next_positive_subdir(struct dentry *prev, +						struct dentry *root)  { -	struct list_head *next = p->d_subdirs.next; +	struct autofs_sb_info *sbi = autofs4_sbi(root->d_sb); +	struct list_head *next; +	struct dentry *q; + +	spin_lock(&sbi->lookup_lock); +	spin_lock(&root->d_lock); + +	if (prev) +		next = prev->d_u.d_child.next; +	else { +		prev = dget_dlock(root); +		next = prev->d_subdirs.next; +	} + +cont: +	if (next == &root->d_subdirs) { +		spin_unlock(&root->d_lock); +		spin_unlock(&sbi->lookup_lock); +		dput(prev); +		return NULL; +	} + +	q = list_entry(next, struct dentry, d_u.d_child); +	spin_lock_nested(&q->d_lock, DENTRY_D_LOCK_NESTED); +	/* Already gone or negative dentry (under construction) - try next */ +	if (!d_count(q) || !simple_positive(q)) { +		spin_unlock(&q->d_lock); +		next = q->d_u.d_child.next; +		goto cont; +	} +	dget_dlock(q); +	spin_unlock(&q->d_lock); +	spin_unlock(&root->d_lock); +	spin_unlock(&sbi->lookup_lock); + +	dput(prev); + +	return q; +} + +/* + * Calculate and dget next entry in top down tree traversal. + */ +static struct dentry *get_next_positive_dentry(struct dentry *prev, +						struct dentry *root) +{ +	struct autofs_sb_info *sbi = autofs4_sbi(root->d_sb); +	struct list_head *next; +	struct dentry *p, *ret; + +	if (prev == NULL) +		return dget(root); + +	spin_lock(&sbi->lookup_lock); +relock: +	p = prev; +	spin_lock(&p->d_lock); +again: +	next = p->d_subdirs.next;  	if (next == &p->d_subdirs) {  		while (1) { -			if (p == root) +			struct dentry *parent; + +			if (p == root) { +				spin_unlock(&p->d_lock); +				spin_unlock(&sbi->lookup_lock); +				dput(prev);  				return NULL; +			} + +			parent = p->d_parent; +			if (!spin_trylock(&parent->d_lock)) { +				spin_unlock(&p->d_lock); +				cpu_relax(); +				goto relock; +			} +			spin_unlock(&p->d_lock);  			next = p->d_u.d_child.next; -			if (next != &p->d_parent->d_subdirs) +			p = parent; +			if (next != &parent->d_subdirs)  				break; -			p = p->d_parent;  		}  	} -	return list_entry(next, struct dentry, d_u.d_child); +	ret = list_entry(next, struct dentry, d_u.d_child); + +	spin_lock_nested(&ret->d_lock, DENTRY_D_LOCK_NESTED); +	/* Negative dentry - try next */ +	if (!simple_positive(ret)) { +		spin_unlock(&p->d_lock); +		lock_set_subclass(&ret->d_lock.dep_map, 0, _RET_IP_); +		p = ret; +		goto again; +	} +	dget_dlock(ret); +	spin_unlock(&ret->d_lock); +	spin_unlock(&p->d_lock); +	spin_unlock(&sbi->lookup_lock); + +	dput(prev); + +	return ret;  }  /* @@ -158,18 +234,11 @@ static int autofs4_tree_busy(struct vfsmount *mnt,  	if (!simple_positive(top))  		return 1; -	spin_lock(&dcache_lock); -	for (p = top; p; p = next_dentry(p, top)) { -		/* Negative dentry - give up */ -		if (!simple_positive(p)) -			continue; - +	p = NULL; +	while ((p = get_next_positive_dentry(p, top))) {  		DPRINTK("dentry %p %.*s",  			p, (int) p->d_name.len, p->d_name.name); -		p = dget(p); -		spin_unlock(&dcache_lock); -  		/*  		 * Is someone visiting anywhere in the subtree ?  		 * If there's no mount we need to check the usage @@ -198,16 +267,13 @@ static int autofs4_tree_busy(struct vfsmount *mnt,  			else  				ino_count++; -			if (atomic_read(&p->d_count) > ino_count) { +			if (d_count(p) > ino_count) {  				top_ino->last_used = jiffies;  				dput(p);  				return 1;  			}  		} -		dput(p); -		spin_lock(&dcache_lock);  	} -	spin_unlock(&dcache_lock);  	/* Timeout of a tree mount is ultimately determined by its top dentry */  	if (!autofs4_can_expire(top, timeout, do_now)) @@ -226,32 +292,21 @@ static struct dentry *autofs4_check_leaves(struct vfsmount *mnt,  	DPRINTK("parent %p %.*s",  		parent, (int)parent->d_name.len, parent->d_name.name); -	spin_lock(&dcache_lock); -	for (p = parent; p; p = next_dentry(p, parent)) { -		/* Negative dentry - give up */ -		if (!simple_positive(p)) -			continue; - +	p = NULL; +	while ((p = get_next_positive_dentry(p, parent))) {  		DPRINTK("dentry %p %.*s",  			p, (int) p->d_name.len, p->d_name.name); -		p = dget(p); -		spin_unlock(&dcache_lock); -  		if (d_mountpoint(p)) {  			/* Can we umount this guy */  			if (autofs4_mount_busy(mnt, p)) -				goto cont; +				continue;  			/* Can we expire this guy */  			if (autofs4_can_expire(p, timeout, do_now))  				return p;  		} -cont: -		dput(p); -		spin_lock(&dcache_lock);  	} -	spin_unlock(&dcache_lock);  	return NULL;  } @@ -264,6 +319,7 @@ struct dentry *autofs4_expire_direct(struct super_block *sb,  	unsigned long timeout;  	struct dentry *root = dget(sb->s_root);  	int do_now = how & AUTOFS_EXP_IMMEDIATE; +	struct autofs_info *ino;  	if (!root)  		return NULL; @@ -272,17 +328,18 @@ struct dentry *autofs4_expire_direct(struct super_block *sb,  	timeout = sbi->exp_timeout;  	spin_lock(&sbi->fs_lock); +	ino = autofs4_dentry_ino(root); +	/* No point expiring a pending mount */ +	if (ino->flags & AUTOFS_INF_PENDING) +		goto out;  	if (!autofs4_direct_busy(mnt, root, timeout, do_now)) {  		struct autofs_info *ino = autofs4_dentry_ino(root); -		if (d_mountpoint(root)) { -			ino->flags |= AUTOFS_INF_MOUNTPOINT; -			root->d_mounted--; -		}  		ino->flags |= AUTOFS_INF_EXPIRING;  		init_completion(&ino->expire_complete);  		spin_unlock(&sbi->fs_lock);  		return root;  	} +out:  	spin_unlock(&sbi->fs_lock);  	dput(root); @@ -302,8 +359,8 @@ struct dentry *autofs4_expire_indirect(struct super_block *sb,  {  	unsigned long timeout;  	struct dentry *root = sb->s_root; +	struct dentry *dentry;  	struct dentry *expired = NULL; -	struct list_head *next;  	int do_now = how & AUTOFS_EXP_IMMEDIATE;  	int exp_leaves = how & AUTOFS_EXP_LEAVES;  	struct autofs_info *ino; @@ -315,25 +372,13 @@ struct dentry *autofs4_expire_indirect(struct super_block *sb,  	now = jiffies;  	timeout = sbi->exp_timeout; -	spin_lock(&dcache_lock); -	next = root->d_subdirs.next; - -	/* On exit from the loop expire is set to a dgot dentry -	 * to expire or it's NULL */ -	while ( next != &root->d_subdirs ) { -		struct dentry *dentry = list_entry(next, struct dentry, d_u.d_child); - -		/* Negative dentry - give up */ -		if (!simple_positive(dentry)) { -			next = next->next; -			continue; -		} - -		dentry = dget(dentry); -		spin_unlock(&dcache_lock); - +	dentry = NULL; +	while ((dentry = get_next_positive_subdir(dentry, root))) {  		spin_lock(&sbi->fs_lock);  		ino = autofs4_dentry_ino(dentry); +		/* No point expiring a pending mount */ +		if (ino->flags & AUTOFS_INF_PENDING) +			goto next;  		/*  		 * Case 1: (i) indirect mount or top level pseudo direct mount @@ -345,11 +390,6 @@ struct dentry *autofs4_expire_indirect(struct super_block *sb,  			DPRINTK("checking mountpoint %p %.*s",  				dentry, (int)dentry->d_name.len, dentry->d_name.name); -			/* Path walk currently on this dentry? */ -			ino_count = atomic_read(&ino->count) + 2; -			if (atomic_read(&dentry->d_count) > ino_count) -				goto next; -  			/* Can we umount this guy */  			if (autofs4_mount_busy(mnt, dentry))  				goto next; @@ -362,6 +402,20 @@ struct dentry *autofs4_expire_indirect(struct super_block *sb,  			goto next;  		} +		if (dentry->d_inode && S_ISLNK(dentry->d_inode->i_mode)) { +			DPRINTK("checking symlink %p %.*s", +				dentry, (int)dentry->d_name.len, dentry->d_name.name); +			/* +			 * A symlink can't be "busy" in the usual sense so +			 * just check last used for expire timeout. +			 */ +			if (autofs4_can_expire(dentry, timeout, do_now)) { +				expired = dentry; +				goto found; +			} +			goto next; +		} +  		if (simple_empty(dentry))  			goto next; @@ -369,7 +423,7 @@ struct dentry *autofs4_expire_indirect(struct super_block *sb,  		if (!exp_leaves) {  			/* Path walk currently on this dentry? */  			ino_count = atomic_read(&ino->count) + 1; -			if (atomic_read(&dentry->d_count) > ino_count) +			if (d_count(dentry) > ino_count)  				goto next;  			if (!autofs4_tree_busy(mnt, dentry, timeout, do_now)) { @@ -383,7 +437,7 @@ struct dentry *autofs4_expire_indirect(struct super_block *sb,  		} else {  			/* Path walk currently on this dentry? */  			ino_count = atomic_read(&ino->count) + 1; -			if (atomic_read(&dentry->d_count) > ino_count) +			if (d_count(dentry) > ino_count)  				goto next;  			expired = autofs4_check_leaves(mnt, dentry, timeout, do_now); @@ -394,11 +448,7 @@ struct dentry *autofs4_expire_indirect(struct super_block *sb,  		}  next:  		spin_unlock(&sbi->fs_lock); -		dput(dentry); -		spin_lock(&dcache_lock); -		next = next->next;  	} -	spin_unlock(&dcache_lock);  	return NULL;  found: @@ -408,9 +458,13 @@ found:  	ino->flags |= AUTOFS_INF_EXPIRING;  	init_completion(&ino->expire_complete);  	spin_unlock(&sbi->fs_lock); -	spin_lock(&dcache_lock); +	spin_lock(&sbi->lookup_lock); +	spin_lock(&expired->d_parent->d_lock); +	spin_lock_nested(&expired->d_lock, DENTRY_D_LOCK_NESTED);  	list_move(&expired->d_parent->d_subdirs, &expired->d_u.d_child); -	spin_unlock(&dcache_lock); +	spin_unlock(&expired->d_lock); +	spin_unlock(&expired->d_parent->d_lock); +	spin_unlock(&sbi->lookup_lock);  	return expired;  } @@ -498,10 +552,6 @@ int autofs4_do_expire_multi(struct super_block *sb, struct vfsmount *mnt,  		ret = autofs4_wait(sbi, dentry, NFY_EXPIRE);  		spin_lock(&sbi->fs_lock); -		if (ino->flags & AUTOFS_INF_MOUNTPOINT) { -			sb->s_root->d_mounted++; -			ino->flags &= ~AUTOFS_INF_MOUNTPOINT; -		}  		ino->flags &= ~AUTOFS_INF_EXPIRING;  		complete_all(&ino->expire_complete);  		spin_unlock(&sbi->fs_lock); diff --git a/fs/autofs4/init.c b/fs/autofs4/init.c index c038727b405..b3db517e89e 100644 --- a/fs/autofs4/init.c +++ b/fs/autofs4/init.c @@ -26,16 +26,17 @@ static struct file_system_type autofs_fs_type = {  	.mount		= autofs_mount,  	.kill_sb	= autofs4_kill_sb,  }; +MODULE_ALIAS_FS("autofs");  static int __init init_autofs4_fs(void)  {  	int err; +	autofs_dev_ioctl_init(); +  	err = register_filesystem(&autofs_fs_type);  	if (err) -		return err; - -	autofs_dev_ioctl_init(); +		autofs_dev_ioctl_exit();  	return err;  } diff --git a/fs/autofs4/inode.c b/fs/autofs4/inode.c index ac87e49fa70..1c55388ae63 100644 --- a/fs/autofs4/inode.c +++ b/fs/autofs4/inode.c @@ -22,77 +22,27 @@  #include "autofs_i.h"  #include <linux/module.h> -static void ino_lnkfree(struct autofs_info *ino) +struct autofs_info *autofs4_new_ino(struct autofs_sb_info *sbi)  { -	if (ino->u.symlink) { -		kfree(ino->u.symlink); -		ino->u.symlink = NULL; -	} -} - -struct autofs_info *autofs4_init_ino(struct autofs_info *ino, -				     struct autofs_sb_info *sbi, mode_t mode) -{ -	int reinit = 1; - -	if (ino == NULL) { -		reinit = 0; -		ino = kmalloc(sizeof(*ino), GFP_KERNEL); -	} - -	if (ino == NULL) -		return NULL; - -	if (!reinit) { -		ino->flags = 0; -		ino->inode = NULL; -		ino->dentry = NULL; -		ino->size = 0; +	struct autofs_info *ino = kzalloc(sizeof(*ino), GFP_KERNEL); +	if (ino) {  		INIT_LIST_HEAD(&ino->active); -		ino->active_count = 0;  		INIT_LIST_HEAD(&ino->expiring); -		atomic_set(&ino->count, 0); +		ino->last_used = jiffies; +		ino->sbi = sbi;  	} +	return ino; +} -	ino->uid = 0; -	ino->gid = 0; -	ino->mode = mode; +void autofs4_clean_ino(struct autofs_info *ino) +{ +	ino->uid = GLOBAL_ROOT_UID; +	ino->gid = GLOBAL_ROOT_GID;  	ino->last_used = jiffies; - -	ino->sbi = sbi; - -	if (reinit && ino->free) -		(ino->free)(ino); - -	memset(&ino->u, 0, sizeof(ino->u)); - -	ino->free = NULL; - -	if (S_ISLNK(mode)) -		ino->free = ino_lnkfree; - -	return ino;  }  void autofs4_free_ino(struct autofs_info *ino)  { -	struct autofs_info *p_ino; - -	if (ino->dentry) { -		ino->dentry->d_fsdata = NULL; -		if (ino->dentry->d_inode) { -			struct dentry *parent = ino->dentry->d_parent; -			if (atomic_dec_and_test(&ino->count)) { -				p_ino = autofs4_dentry_ino(parent); -				if (p_ino && parent != ino->dentry) -					atomic_dec(&p_ino->count); -			} -			dput(ino->dentry); -		} -		ino->dentry = NULL; -	} -	if (ino->free) -		(ino->free)(ino);  	kfree(ino);  } @@ -106,34 +56,34 @@ void autofs4_kill_sb(struct super_block *sb)  	 * just call kill_anon_super when we are called from  	 * deactivate_super.  	 */ -	if (!sbi) -		goto out_kill_sb; - -	/* Free wait queues, close pipe */ -	autofs4_catatonic_mode(sbi); - -	sb->s_fs_info = NULL; -	kfree(sbi); +	if (sbi) { +		/* Free wait queues, close pipe */ +		autofs4_catatonic_mode(sbi); +		put_pid(sbi->oz_pgrp); +	} -out_kill_sb:  	DPRINTK("shutting down");  	kill_litter_super(sb); +	if (sbi) +		kfree_rcu(sbi, rcu);  } -static int autofs4_show_options(struct seq_file *m, struct vfsmount *mnt) +static int autofs4_show_options(struct seq_file *m, struct dentry *root)  { -	struct autofs_sb_info *sbi = autofs4_sbi(mnt->mnt_sb); -	struct inode *root_inode = mnt->mnt_sb->s_root->d_inode; +	struct autofs_sb_info *sbi = autofs4_sbi(root->d_sb); +	struct inode *root_inode = root->d_sb->s_root->d_inode;  	if (!sbi)  		return 0;  	seq_printf(m, ",fd=%d", sbi->pipefd); -	if (root_inode->i_uid != 0) -		seq_printf(m, ",uid=%u", root_inode->i_uid); -	if (root_inode->i_gid != 0) -		seq_printf(m, ",gid=%u", root_inode->i_gid); -	seq_printf(m, ",pgrp=%d", sbi->oz_pgrp); +	if (!uid_eq(root_inode->i_uid, GLOBAL_ROOT_UID)) +		seq_printf(m, ",uid=%u", +			from_kuid_munged(&init_user_ns, root_inode->i_uid)); +	if (!gid_eq(root_inode->i_gid, GLOBAL_ROOT_GID)) +		seq_printf(m, ",gid=%u", +			from_kgid_munged(&init_user_ns, root_inode->i_gid)); +	seq_printf(m, ",pgrp=%d", pid_vnr(sbi->oz_pgrp));  	seq_printf(m, ",timeout=%lu", sbi->exp_timeout/HZ);  	seq_printf(m, ",minproto=%d", sbi->min_proto);  	seq_printf(m, ",maxproto=%d", sbi->max_proto); @@ -148,9 +98,16 @@ static int autofs4_show_options(struct seq_file *m, struct vfsmount *mnt)  	return 0;  } +static void autofs4_evict_inode(struct inode *inode) +{ +	clear_inode(inode); +	kfree(inode->i_private); +} +  static const struct super_operations autofs4_sops = {  	.statfs		= simple_statfs,  	.show_options	= autofs4_show_options, +	.evict_inode	= autofs4_evict_inode,  };  enum {Opt_err, Opt_fd, Opt_uid, Opt_gid, Opt_pgrp, Opt_minproto, Opt_maxproto, @@ -169,8 +126,9 @@ static const match_table_t tokens = {  	{Opt_err, NULL}  }; -static int parse_options(char *options, int *pipefd, uid_t *uid, gid_t *gid, -		pid_t *pgrp, unsigned int *type, int *minproto, int *maxproto) +static int parse_options(char *options, int *pipefd, kuid_t *uid, kgid_t *gid, +			 int *pgrp, bool *pgrp_set, unsigned int *type, +			 int *minproto, int *maxproto)  {  	char *p;  	substring_t args[MAX_OPT_ARGS]; @@ -178,7 +136,6 @@ static int parse_options(char *options, int *pipefd, uid_t *uid, gid_t *gid,  	*uid = current_uid();  	*gid = current_gid(); -	*pgrp = task_pgrp_nr(current);  	*minproto = AUTOFS_MIN_PROTO_VERSION;  	*maxproto = AUTOFS_MAX_PROTO_VERSION; @@ -202,17 +159,22 @@ static int parse_options(char *options, int *pipefd, uid_t *uid, gid_t *gid,  		case Opt_uid:  			if (match_int(args, &option))  				return 1; -			*uid = option; +			*uid = make_kuid(current_user_ns(), option); +			if (!uid_valid(*uid)) +				return 1;  			break;  		case Opt_gid:  			if (match_int(args, &option))  				return 1; -			*gid = option; +			*gid = make_kgid(current_user_ns(), option); +			if (!gid_valid(*gid)) +				return 1;  			break;  		case Opt_pgrp:  			if (match_int(args, &option))  				return 1;  			*pgrp = option; +			*pgrp_set = true;  			break;  		case Opt_minproto:  			if (match_int(args, &option)) @@ -240,21 +202,6 @@ static int parse_options(char *options, int *pipefd, uid_t *uid, gid_t *gid,  	return (*pipefd < 0);  } -static struct autofs_info *autofs4_mkroot(struct autofs_sb_info *sbi) -{ -	struct autofs_info *ino; - -	ino = autofs4_init_ino(NULL, sbi, S_IFDIR | 0755); -	if (!ino) -		return NULL; - -	return ino; -} - -static const struct dentry_operations autofs4_sb_dentry_operations = { -	.d_release      = autofs4_dentry_release, -}; -  int autofs4_fill_super(struct super_block *s, void *data, int silent)  {  	struct inode * root_inode; @@ -263,10 +210,13 @@ int autofs4_fill_super(struct super_block *s, void *data, int silent)  	int pipefd;  	struct autofs_sb_info *sbi;  	struct autofs_info *ino; +	int pgrp = 0; +	bool pgrp_set = false; +	int ret = -EINVAL;  	sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);  	if (!sbi) -		goto fail_unlock; +		return -ENOMEM;  	DPRINTK("starting up, sbi = %p",sbi);  	s->s_fs_info = sbi; @@ -275,7 +225,7 @@ int autofs4_fill_super(struct super_block *s, void *data, int silent)  	sbi->pipe = NULL;  	sbi->catatonic = 1;  	sbi->exp_timeout = 0; -	sbi->oz_pgrp = task_pgrp_nr(current); +	sbi->oz_pgrp = NULL;  	sbi->sb = s;  	sbi->version = 0;  	sbi->sub_version = 0; @@ -283,6 +233,7 @@ int autofs4_fill_super(struct super_block *s, void *data, int silent)  	sbi->min_proto = 0;  	sbi->max_proto = 0;  	mutex_init(&sbi->wq_mutex); +	mutex_init(&sbi->pipe_mutex);  	spin_lock_init(&sbi->fs_lock);  	sbi->queues = NULL;  	spin_lock_init(&sbi->lookup_lock); @@ -292,38 +243,49 @@ int autofs4_fill_super(struct super_block *s, void *data, int silent)  	s->s_blocksize_bits = 10;  	s->s_magic = AUTOFS_SUPER_MAGIC;  	s->s_op = &autofs4_sops; +	s->s_d_op = &autofs4_dentry_operations;  	s->s_time_gran = 1;  	/*  	 * Get the root inode and dentry, but defer checking for errors.  	 */ -	ino = autofs4_mkroot(sbi); -	if (!ino) +	ino = autofs4_new_ino(sbi); +	if (!ino) { +		ret = -ENOMEM;  		goto fail_free; -	root_inode = autofs4_get_inode(s, ino); -	if (!root_inode) -		goto fail_ino; - -	root = d_alloc_root(root_inode); +	} +	root_inode = autofs4_get_inode(s, S_IFDIR | 0755); +	root = d_make_root(root_inode);  	if (!root) -		goto fail_iput; +		goto fail_ino;  	pipe = NULL; -	root->d_op = &autofs4_sb_dentry_operations;  	root->d_fsdata = ino;  	/* Can this call block? */  	if (parse_options(data, &pipefd, &root_inode->i_uid, &root_inode->i_gid, -				&sbi->oz_pgrp, &sbi->type, &sbi->min_proto, -				&sbi->max_proto)) { +			  &pgrp, &pgrp_set, &sbi->type, &sbi->min_proto, +			  &sbi->max_proto)) {  		printk("autofs: called with bogus options\n");  		goto fail_dput;  	} +	if (pgrp_set) { +		sbi->oz_pgrp = find_get_pid(pgrp); +		if (!sbi->oz_pgrp) { +			pr_warn("autofs: could not find process group %d\n", +				pgrp); +			goto fail_dput; +		} +	} else { +		sbi->oz_pgrp = get_task_pid(current, PIDTYPE_PGID); +	} + +	if (autofs_type_trigger(sbi->type)) +		__managed_dentry_set_managed(root); +  	root_inode->i_fop = &autofs4_root_operations; -	root_inode->i_op = autofs_type_trigger(sbi->type) ? -			&autofs4_direct_root_inode_operations : -			&autofs4_indirect_root_inode_operations; +	root_inode->i_op = &autofs4_dir_inode_operations;  	/* Couldn't this be tested earlier? */  	if (sbi->max_proto < AUTOFS_MIN_PROTO_VERSION || @@ -342,14 +304,15 @@ int autofs4_fill_super(struct super_block *s, void *data, int silent)  		sbi->version = sbi->max_proto;  	sbi->sub_version = AUTOFS_PROTO_SUBVERSION; -	DPRINTK("pipe fd = %d, pgrp = %u", pipefd, sbi->oz_pgrp); +	DPRINTK("pipe fd = %d, pgrp = %u", pipefd, pid_nr(sbi->oz_pgrp));  	pipe = fget(pipefd); -	 +  	if (!pipe) {  		printk("autofs: could not open pipe file descriptor\n");  		goto fail_dput;  	} -	if (!pipe->f_op || !pipe->f_op->write) +	ret = autofs_prepare_pipe(pipe); +	if (ret < 0)  		goto fail_fput;  	sbi->pipe = pipe;  	sbi->pipefd = pipefd; @@ -371,28 +334,23 @@ fail_fput:  fail_dput:  	dput(root);  	goto fail_free; -fail_iput: -	printk("autofs: get root dentry failed\n"); -	iput(root_inode);  fail_ino:  	kfree(ino);  fail_free: +	put_pid(sbi->oz_pgrp);  	kfree(sbi);  	s->s_fs_info = NULL; -fail_unlock: -	return -EINVAL; +	return ret;  } -struct inode *autofs4_get_inode(struct super_block *sb, -				struct autofs_info *inf) +struct inode *autofs4_get_inode(struct super_block *sb, umode_t mode)  {  	struct inode *inode = new_inode(sb);  	if (inode == NULL)  		return NULL; -	inf->inode = inode; -	inode->i_mode = inf->mode; +	inode->i_mode = mode;  	if (sb->s_root) {  		inode->i_uid = sb->s_root->d_inode->i_uid;  		inode->i_gid = sb->s_root->d_inode->i_gid; @@ -400,12 +358,11 @@ struct inode *autofs4_get_inode(struct super_block *sb,  	inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME;  	inode->i_ino = get_next_ino(); -	if (S_ISDIR(inf->mode)) { -		inode->i_nlink = 2; +	if (S_ISDIR(mode)) { +		set_nlink(inode, 2);  		inode->i_op = &autofs4_dir_inode_operations;  		inode->i_fop = &autofs4_dir_operations; -	} else if (S_ISLNK(inf->mode)) { -		inode->i_size = inf->size; +	} else if (S_ISLNK(mode)) {  		inode->i_op = &autofs4_symlink_inode_operations;  	} diff --git a/fs/autofs4/root.c b/fs/autofs4/root.c index d5c1401f003..cc87c1abac9 100644 --- a/fs/autofs4/root.c +++ b/fs/autofs4/root.c @@ -26,23 +26,22 @@  static int autofs4_dir_symlink(struct inode *,struct dentry *,const char *);  static int autofs4_dir_unlink(struct inode *,struct dentry *);  static int autofs4_dir_rmdir(struct inode *,struct dentry *); -static int autofs4_dir_mkdir(struct inode *,struct dentry *,int); +static int autofs4_dir_mkdir(struct inode *,struct dentry *,umode_t);  static long autofs4_root_ioctl(struct file *,unsigned int,unsigned long);  #ifdef CONFIG_COMPAT  static long autofs4_root_compat_ioctl(struct file *,unsigned int,unsigned long);  #endif  static int autofs4_dir_open(struct inode *inode, struct file *file); -static struct dentry *autofs4_lookup(struct inode *,struct dentry *, struct nameidata *); -static void *autofs4_follow_link(struct dentry *, struct nameidata *); - -#define TRIGGER_FLAGS   (LOOKUP_CONTINUE | LOOKUP_DIRECTORY) -#define TRIGGER_INTENTS (LOOKUP_OPEN | LOOKUP_CREATE) +static struct dentry *autofs4_lookup(struct inode *,struct dentry *, unsigned int); +static struct vfsmount *autofs4_d_automount(struct path *); +static int autofs4_d_manage(struct dentry *, bool); +static void autofs4_dentry_release(struct dentry *);  const struct file_operations autofs4_root_operations = {  	.open		= dcache_dir_open,  	.release	= dcache_dir_close,  	.read		= generic_read_dir, -	.readdir	= dcache_readdir, +	.iterate	= dcache_readdir,  	.llseek		= dcache_dir_lseek,  	.unlocked_ioctl	= autofs4_root_ioctl,  #ifdef CONFIG_COMPAT @@ -54,11 +53,11 @@ const struct file_operations autofs4_dir_operations = {  	.open		= autofs4_dir_open,  	.release	= dcache_dir_close,  	.read		= generic_read_dir, -	.readdir	= dcache_readdir, +	.iterate	= dcache_readdir,  	.llseek		= dcache_dir_lseek,  }; -const struct inode_operations autofs4_indirect_root_inode_operations = { +const struct inode_operations autofs4_dir_inode_operations = {  	.lookup		= autofs4_lookup,  	.unlink		= autofs4_dir_unlink,  	.symlink	= autofs4_dir_symlink, @@ -66,20 +65,10 @@ const struct inode_operations autofs4_indirect_root_inode_operations = {  	.rmdir		= autofs4_dir_rmdir,  }; -const struct inode_operations autofs4_direct_root_inode_operations = { -	.lookup		= autofs4_lookup, -	.unlink		= autofs4_dir_unlink, -	.mkdir		= autofs4_dir_mkdir, -	.rmdir		= autofs4_dir_rmdir, -	.follow_link	= autofs4_follow_link, -}; - -const struct inode_operations autofs4_dir_inode_operations = { -	.lookup		= autofs4_lookup, -	.unlink		= autofs4_dir_unlink, -	.symlink	= autofs4_dir_symlink, -	.mkdir		= autofs4_dir_mkdir, -	.rmdir		= autofs4_dir_rmdir, +const struct dentry_operations autofs4_dentry_operations = { +	.d_automount	= autofs4_d_automount, +	.d_manage	= autofs4_d_manage, +	.d_release	= autofs4_dentry_release,  };  static void autofs4_add_active(struct dentry *dentry) @@ -114,14 +103,6 @@ static void autofs4_del_active(struct dentry *dentry)  	return;  } -static unsigned int autofs4_need_mount(unsigned int flags) -{ -	unsigned int res = 0; -	if (flags & (TRIGGER_FLAGS | TRIGGER_INTENTS)) -		res = 1; -	return res; -} -  static int autofs4_dir_open(struct inode *inode, struct file *file)  {  	struct dentry *dentry = file->f_path.dentry; @@ -142,275 +123,38 @@ static int autofs4_dir_open(struct inode *inode, struct file *file)  	 * autofs file system so just let the libfs routines handle  	 * it.  	 */ -	spin_lock(&dcache_lock); -	if (!d_mountpoint(dentry) && list_empty(&dentry->d_subdirs)) { -		spin_unlock(&dcache_lock); +	spin_lock(&sbi->lookup_lock); +	if (!d_mountpoint(dentry) && simple_empty(dentry)) { +		spin_unlock(&sbi->lookup_lock);  		return -ENOENT;  	} -	spin_unlock(&dcache_lock); +	spin_unlock(&sbi->lookup_lock);  out:  	return dcache_dir_open(inode, file);  } -static int try_to_fill_dentry(struct dentry *dentry, int flags) +static void autofs4_dentry_release(struct dentry *de)  { -	struct autofs_sb_info *sbi = autofs4_sbi(dentry->d_sb); -	struct autofs_info *ino = autofs4_dentry_ino(dentry); -	int status; - -	DPRINTK("dentry=%p %.*s ino=%p", -		 dentry, dentry->d_name.len, dentry->d_name.name, dentry->d_inode); - -	/* -	 * Wait for a pending mount, triggering one if there -	 * isn't one already -	 */ -	if (dentry->d_inode == NULL) { -		DPRINTK("waiting for mount name=%.*s", -			 dentry->d_name.len, dentry->d_name.name); - -		status = autofs4_wait(sbi, dentry, NFY_MOUNT); - -		DPRINTK("mount done status=%d", status); - -		/* Turn this into a real negative dentry? */ -		if (status == -ENOENT) { -			spin_lock(&sbi->fs_lock); -			ino->flags &= ~AUTOFS_INF_PENDING; -			spin_unlock(&sbi->fs_lock); -			return status; -		} else if (status) { -			/* Return a negative dentry, but leave it "pending" */ -			return status; -		} -	/* Trigger mount for path component or follow link */ -	} else if (ino->flags & AUTOFS_INF_PENDING || -			autofs4_need_mount(flags)) { -		DPRINTK("waiting for mount name=%.*s", -			dentry->d_name.len, dentry->d_name.name); - -		spin_lock(&sbi->fs_lock); -		ino->flags |= AUTOFS_INF_PENDING; -		spin_unlock(&sbi->fs_lock); -		status = autofs4_wait(sbi, dentry, NFY_MOUNT); - -		DPRINTK("mount done status=%d", status); - -		if (status) { -			spin_lock(&sbi->fs_lock); -			ino->flags &= ~AUTOFS_INF_PENDING; -			spin_unlock(&sbi->fs_lock); -			return status; -		} -	} - -	/* Initialize expiry counter after successful mount */ -	ino->last_used = jiffies; - -	spin_lock(&sbi->fs_lock); -	ino->flags &= ~AUTOFS_INF_PENDING; -	spin_unlock(&sbi->fs_lock); - -	return 0; -} - -/* For autofs direct mounts the follow link triggers the mount */ -static void *autofs4_follow_link(struct dentry *dentry, struct nameidata *nd) -{ -	struct autofs_sb_info *sbi = autofs4_sbi(dentry->d_sb); -	struct autofs_info *ino = autofs4_dentry_ino(dentry); -	int oz_mode = autofs4_oz_mode(sbi); -	unsigned int lookup_type; -	int status; - -	DPRINTK("dentry=%p %.*s oz_mode=%d nd->flags=%d", -		dentry, dentry->d_name.len, dentry->d_name.name, oz_mode, -		nd->flags); -	/* -	 * For an expire of a covered direct or offset mount we need -	 * to break out of follow_down() at the autofs mount trigger -	 * (d_mounted--), so we can see the expiring flag, and manage -	 * the blocking and following here until the expire is completed. -	 */ -	if (oz_mode) { -		spin_lock(&sbi->fs_lock); -		if (ino->flags & AUTOFS_INF_EXPIRING) { -			spin_unlock(&sbi->fs_lock); -			/* Follow down to our covering mount. */ -			if (!follow_down(&nd->path)) -				goto done; -			goto follow; -		} -		spin_unlock(&sbi->fs_lock); -		goto done; -	} - -	/* If an expire request is pending everyone must wait. */ -	autofs4_expire_wait(dentry); - -	/* We trigger a mount for almost all flags */ -	lookup_type = autofs4_need_mount(nd->flags); -	spin_lock(&sbi->fs_lock); -	spin_lock(&dcache_lock); -	if (!(lookup_type || ino->flags & AUTOFS_INF_PENDING)) { -		spin_unlock(&dcache_lock); -		spin_unlock(&sbi->fs_lock); -		goto follow; -	} - -	/* -	 * If the dentry contains directories then it is an autofs -	 * multi-mount with no root mount offset. So don't try to -	 * mount it again. -	 */ -	if (ino->flags & AUTOFS_INF_PENDING || -	    (!d_mountpoint(dentry) && list_empty(&dentry->d_subdirs))) { -		spin_unlock(&dcache_lock); -		spin_unlock(&sbi->fs_lock); - -		status = try_to_fill_dentry(dentry, nd->flags); -		if (status) -			goto out_error; - -		goto follow; -	} -	spin_unlock(&dcache_lock); -	spin_unlock(&sbi->fs_lock); -follow: -	/* -	 * If there is no root mount it must be an autofs -	 * multi-mount with no root offset so we don't need -	 * to follow it. -	 */ -	if (d_mountpoint(dentry)) { -		if (!autofs4_follow_mount(&nd->path)) { -			status = -ENOENT; -			goto out_error; -		} -	} - -done: -	return NULL; - -out_error: -	path_put(&nd->path); -	return ERR_PTR(status); -} - -/* - * Revalidate is called on every cache lookup.  Some of those - * cache lookups may actually happen while the dentry is not - * yet completely filled in, and revalidate has to delay such - * lookups.. - */ -static int autofs4_revalidate(struct dentry *dentry, struct nameidata *nd) -{ -	struct inode *dir = dentry->d_parent->d_inode; -	struct autofs_sb_info *sbi = autofs4_sbi(dir->i_sb); -	int oz_mode = autofs4_oz_mode(sbi); -	int flags = nd ? nd->flags : 0; -	int status = 1; - -	/* Pending dentry */ -	spin_lock(&sbi->fs_lock); -	if (autofs4_ispending(dentry)) { -		/* The daemon never causes a mount to trigger */ -		spin_unlock(&sbi->fs_lock); - -		if (oz_mode) -			return 1; - -		/* -		 * If the directory has gone away due to an expire -		 * we have been called as ->d_revalidate() and so -		 * we need to return false and proceed to ->lookup(). -		 */ -		if (autofs4_expire_wait(dentry) == -EAGAIN) -			return 0; - -		/* -		 * A zero status is success otherwise we have a -		 * negative error code. -		 */ -		status = try_to_fill_dentry(dentry, flags); -		if (status == 0) -			return 1; - -		return status; -	} -	spin_unlock(&sbi->fs_lock); - -	/* Negative dentry.. invalidate if "old" */ -	if (dentry->d_inode == NULL) -		return 0; - -	/* Check for a non-mountpoint directory with no contents */ -	spin_lock(&dcache_lock); -	if (S_ISDIR(dentry->d_inode->i_mode) && -	    !d_mountpoint(dentry) && list_empty(&dentry->d_subdirs)) { -		DPRINTK("dentry=%p %.*s, emptydir", -			 dentry, dentry->d_name.len, dentry->d_name.name); -		spin_unlock(&dcache_lock); - -		/* The daemon never causes a mount to trigger */ -		if (oz_mode) -			return 1; - -		/* -		 * A zero status is success otherwise we have a -		 * negative error code. -		 */ -		status = try_to_fill_dentry(dentry, flags); -		if (status == 0) -			return 1; - -		return status; -	} -	spin_unlock(&dcache_lock); - -	return 1; -} - -void autofs4_dentry_release(struct dentry *de) -{ -	struct autofs_info *inf; +	struct autofs_info *ino = autofs4_dentry_ino(de); +	struct autofs_sb_info *sbi = autofs4_sbi(de->d_sb);  	DPRINTK("releasing %p", de); -	inf = autofs4_dentry_ino(de); -	de->d_fsdata = NULL; - -	if (inf) { -		struct autofs_sb_info *sbi = autofs4_sbi(de->d_sb); - -		if (sbi) { -			spin_lock(&sbi->lookup_lock); -			if (!list_empty(&inf->active)) -				list_del(&inf->active); -			if (!list_empty(&inf->expiring)) -				list_del(&inf->expiring); -			spin_unlock(&sbi->lookup_lock); -		} - -		inf->dentry = NULL; -		inf->inode = NULL; +	if (!ino) +		return; -		autofs4_free_ino(inf); +	if (sbi) { +		spin_lock(&sbi->lookup_lock); +		if (!list_empty(&ino->active)) +			list_del(&ino->active); +		if (!list_empty(&ino->expiring)) +			list_del(&ino->expiring); +		spin_unlock(&sbi->lookup_lock);  	} -} -/* For dentries of directories in the root dir */ -static const struct dentry_operations autofs4_root_dentry_operations = { -	.d_revalidate	= autofs4_revalidate, -	.d_release	= autofs4_dentry_release, -}; - -/* For other dentries */ -static const struct dentry_operations autofs4_dentry_operations = { -	.d_revalidate	= autofs4_revalidate, -	.d_release	= autofs4_dentry_release, -}; +	autofs4_free_ino(ino); +}  static struct dentry *autofs4_lookup_active(struct dentry *dentry)  { @@ -422,7 +166,6 @@ static struct dentry *autofs4_lookup_active(struct dentry *dentry)  	const unsigned char *str = name->name;  	struct list_head *p, *head; -	spin_lock(&dcache_lock);  	spin_lock(&sbi->lookup_lock);  	head = &sbi->active_list;  	list_for_each(p, head) { @@ -436,7 +179,7 @@ static struct dentry *autofs4_lookup_active(struct dentry *dentry)  		spin_lock(&active->d_lock);  		/* Already gone? */ -		if (atomic_read(&active->d_count) == 0) +		if ((int) d_count(active) <= 0)  			goto next;  		qstr = &active->d_name; @@ -452,17 +195,15 @@ static struct dentry *autofs4_lookup_active(struct dentry *dentry)  			goto next;  		if (d_unhashed(active)) { -			dget(active); +			dget_dlock(active);  			spin_unlock(&active->d_lock);  			spin_unlock(&sbi->lookup_lock); -			spin_unlock(&dcache_lock);  			return active;  		}  next:  		spin_unlock(&active->d_lock);  	}  	spin_unlock(&sbi->lookup_lock); -	spin_unlock(&dcache_lock);  	return NULL;  } @@ -477,7 +218,6 @@ static struct dentry *autofs4_lookup_expiring(struct dentry *dentry)  	const unsigned char *str = name->name;  	struct list_head *p, *head; -	spin_lock(&dcache_lock);  	spin_lock(&sbi->lookup_lock);  	head = &sbi->expiring_list;  	list_for_each(p, head) { @@ -490,7 +230,7 @@ static struct dentry *autofs4_lookup_expiring(struct dentry *dentry)  		spin_lock(&expiring->d_lock); -		/* Bad luck, we've already been dentry_iput */ +		/* We've already been dentry_iput or unlinked */  		if (!expiring->d_inode)  			goto next; @@ -507,152 +247,271 @@ static struct dentry *autofs4_lookup_expiring(struct dentry *dentry)  			goto next;  		if (d_unhashed(expiring)) { -			dget(expiring); +			dget_dlock(expiring);  			spin_unlock(&expiring->d_lock);  			spin_unlock(&sbi->lookup_lock); -			spin_unlock(&dcache_lock);  			return expiring;  		}  next:  		spin_unlock(&expiring->d_lock);  	}  	spin_unlock(&sbi->lookup_lock); -	spin_unlock(&dcache_lock);  	return NULL;  } -/* Lookups in the root directory */ -static struct dentry *autofs4_lookup(struct inode *dir, struct dentry *dentry, struct nameidata *nd) +static int autofs4_mount_wait(struct dentry *dentry)  { -	struct autofs_sb_info *sbi; -	struct autofs_info *ino; -	struct dentry *expiring, *active; -	int oz_mode; - -	DPRINTK("name = %.*s", -		dentry->d_name.len, dentry->d_name.name); - -	/* File name too long to exist */ -	if (dentry->d_name.len > NAME_MAX) -		return ERR_PTR(-ENAMETOOLONG); +	struct autofs_sb_info *sbi = autofs4_sbi(dentry->d_sb); +	struct autofs_info *ino = autofs4_dentry_ino(dentry); +	int status = 0; -	sbi = autofs4_sbi(dir->i_sb); -	oz_mode = autofs4_oz_mode(sbi); +	if (ino->flags & AUTOFS_INF_PENDING) { +		DPRINTK("waiting for mount name=%.*s", +			dentry->d_name.len, dentry->d_name.name); +		status = autofs4_wait(sbi, dentry, NFY_MOUNT); +		DPRINTK("mount wait done status=%d", status); +	} +	ino->last_used = jiffies; +	return status; +} -	DPRINTK("pid = %u, pgrp = %u, catatonic = %d, oz_mode = %d", -		 current->pid, task_pgrp_nr(current), sbi->catatonic, oz_mode); +static int do_expire_wait(struct dentry *dentry) +{ +	struct dentry *expiring; -	active = autofs4_lookup_active(dentry); -	if (active) { -		dentry = active; -		ino = autofs4_dentry_ino(dentry); -	} else { +	expiring = autofs4_lookup_expiring(dentry); +	if (!expiring) +		return autofs4_expire_wait(dentry); +	else {  		/* -		 * Mark the dentry incomplete but don't hash it. We do this -		 * to serialize our inode creation operations (symlink and -		 * mkdir) which prevents deadlock during the callback to -		 * the daemon. Subsequent user space lookups for the same -		 * dentry are placed on the wait queue while the daemon -		 * itself is allowed passage unresticted so the create -		 * operation itself can then hash the dentry. Finally, -		 * we check for the hashed dentry and return the newly -		 * hashed dentry. +		 * If we are racing with expire the request might not +		 * be quite complete, but the directory has been removed +		 * so it must have been successful, just wait for it.  		 */ -		dentry->d_op = &autofs4_root_dentry_operations; +		autofs4_expire_wait(expiring); +		autofs4_del_expiring(expiring); +		dput(expiring); +	} +	return 0; +} -		/* -		 * And we need to ensure that the same dentry is used for -		 * all following lookup calls until it is hashed so that -		 * the dentry flags are persistent throughout the request. -		 */ -		ino = autofs4_init_ino(NULL, sbi, 0555); -		if (!ino) -			return ERR_PTR(-ENOMEM); +static struct dentry *autofs4_mountpoint_changed(struct path *path) +{ +	struct dentry *dentry = path->dentry; +	struct autofs_sb_info *sbi = autofs4_sbi(dentry->d_sb); -		dentry->d_fsdata = ino; -		ino->dentry = dentry; +	/* +	 * If this is an indirect mount the dentry could have gone away +	 * as a result of an expire and a new one created. +	 */ +	if (autofs_type_indirect(sbi->type) && d_unhashed(dentry)) { +		struct dentry *parent = dentry->d_parent; +		struct autofs_info *ino; +		struct dentry *new = d_lookup(parent, &dentry->d_name); +		if (!new) +			return NULL; +		ino = autofs4_dentry_ino(new); +		ino->last_used = jiffies; +		dput(path->dentry); +		path->dentry = new; +	} +	return path->dentry; +} -		autofs4_add_active(dentry); +static struct vfsmount *autofs4_d_automount(struct path *path) +{ +	struct dentry *dentry = path->dentry; +	struct autofs_sb_info *sbi = autofs4_sbi(dentry->d_sb); +	struct autofs_info *ino = autofs4_dentry_ino(dentry); +	int status; -		d_instantiate(dentry, NULL); -	} +	DPRINTK("dentry=%p %.*s", +		dentry, dentry->d_name.len, dentry->d_name.name); -	if (!oz_mode) { -		mutex_unlock(&dir->i_mutex); -		expiring = autofs4_lookup_expiring(dentry); -		if (expiring) { -			/* -			 * If we are racing with expire the request might not -			 * be quite complete but the directory has been removed -			 * so it must have been successful, so just wait for it. -			 */ -			autofs4_expire_wait(expiring); -			autofs4_del_expiring(expiring); -			dput(expiring); -		} +	/* The daemon never triggers a mount. */ +	if (autofs4_oz_mode(sbi)) +		return NULL; -		spin_lock(&sbi->fs_lock); -		ino->flags |= AUTOFS_INF_PENDING; +	/* +	 * If an expire request is pending everyone must wait. +	 * If the expire fails we're still mounted so continue +	 * the follow and return. A return of -EAGAIN (which only +	 * happens with indirect mounts) means the expire completed +	 * and the directory was removed, so just go ahead and try +	 * the mount. +	 */ +	status = do_expire_wait(dentry); +	if (status && status != -EAGAIN) +		return NULL; + +	/* Callback to the daemon to perform the mount or wait */ +	spin_lock(&sbi->fs_lock); +	if (ino->flags & AUTOFS_INF_PENDING) {  		spin_unlock(&sbi->fs_lock); -		if (dentry->d_op && dentry->d_op->d_revalidate) -			(dentry->d_op->d_revalidate)(dentry, nd); -		mutex_lock(&dir->i_mutex); +		status = autofs4_mount_wait(dentry); +		if (status) +			return ERR_PTR(status); +		goto done;  	}  	/* -	 * If we are still pending, check if we had to handle -	 * a signal. If so we can force a restart.. +	 * If the dentry is a symlink it's equivalent to a directory +	 * having d_mountpoint() true, so there's no need to call back +	 * to the daemon.  	 */ -	if (ino->flags & AUTOFS_INF_PENDING) { -		/* See if we were interrupted */ -		if (signal_pending(current)) { -			sigset_t *sigset = ¤t->pending.signal; -			if (sigismember (sigset, SIGKILL) || -			    sigismember (sigset, SIGQUIT) || -			    sigismember (sigset, SIGINT)) { -			    if (active) -				dput(active); -			    return ERR_PTR(-ERESTARTNOINTR); +	if (dentry->d_inode && S_ISLNK(dentry->d_inode->i_mode)) { +		spin_unlock(&sbi->fs_lock); +		goto done; +	} + +	if (!d_mountpoint(dentry)) { +		/* +		 * It's possible that user space hasn't removed directories +		 * after umounting a rootless multi-mount, although it +		 * should. For v5 have_submounts() is sufficient to handle +		 * this because the leaves of the directory tree under the +		 * mount never trigger mounts themselves (they have an autofs +		 * trigger mount mounted on them). But v4 pseudo direct mounts +		 * do need the leaves to to trigger mounts. In this case we +		 * have no choice but to use the list_empty() check and +		 * require user space behave. +		 */ +		if (sbi->version > 4) { +			if (have_submounts(dentry)) { +				spin_unlock(&sbi->fs_lock); +				goto done; +			} +		} else { +			if (!simple_empty(dentry)) { +				spin_unlock(&sbi->fs_lock); +				goto done;  			}  		} -		if (!oz_mode) { -			spin_lock(&sbi->fs_lock); -			ino->flags &= ~AUTOFS_INF_PENDING; +		ino->flags |= AUTOFS_INF_PENDING; +		spin_unlock(&sbi->fs_lock); +		status = autofs4_mount_wait(dentry); +		spin_lock(&sbi->fs_lock); +		ino->flags &= ~AUTOFS_INF_PENDING; +		if (status) {  			spin_unlock(&sbi->fs_lock); +			return ERR_PTR(status);  		}  	} +	spin_unlock(&sbi->fs_lock); +done: +	/* Mount succeeded, check if we ended up with a new dentry */ +	dentry = autofs4_mountpoint_changed(path); +	if (!dentry) +		return ERR_PTR(-ENOENT); + +	return NULL; +} + +static int autofs4_d_manage(struct dentry *dentry, bool rcu_walk) +{ +	struct autofs_sb_info *sbi = autofs4_sbi(dentry->d_sb); +	struct autofs_info *ino = autofs4_dentry_ino(dentry); +	int status; + +	DPRINTK("dentry=%p %.*s", +		dentry, dentry->d_name.len, dentry->d_name.name); + +	/* The daemon never waits. */ +	if (autofs4_oz_mode(sbi)) { +		if (rcu_walk) +			return 0; +		if (!d_mountpoint(dentry)) +			return -EISDIR; +		return 0; +	} + +	/* We need to sleep, so we need pathwalk to be in ref-mode */ +	if (rcu_walk) +		return -ECHILD; + +	/* Wait for pending expires */ +	do_expire_wait(dentry); + +	/* +	 * This dentry may be under construction so wait on mount +	 * completion. +	 */ +	status = autofs4_mount_wait(dentry); +	if (status) +		return status; +	spin_lock(&sbi->fs_lock);  	/* -	 * If this dentry is unhashed, then we shouldn't honour this -	 * lookup.  Returning ENOENT here doesn't do the right thing -	 * for all system calls, but it should be OK for the operations -	 * we permit from an autofs. +	 * If the dentry has been selected for expire while we slept +	 * on the lock then it might go away. We'll deal with that in +	 * ->d_automount() and wait on a new mount if the expire +	 * succeeds or return here if it doesn't (since there's no +	 * mount to follow with a rootless multi-mount).  	 */ -	if (!oz_mode && d_unhashed(dentry)) { +	if (!(ino->flags & AUTOFS_INF_EXPIRING)) {  		/* -		 * A user space application can (and has done in the past) -		 * remove and re-create this directory during the callback. -		 * This can leave us with an unhashed dentry, but a -		 * successful mount!  So we need to perform another -		 * cached lookup in case the dentry now exists. +		 * Any needed mounting has been completed and the path +		 * updated so check if this is a rootless multi-mount so +		 * we can avoid needless calls ->d_automount() and avoid +		 * an incorrect ELOOP error return.  		 */ -		struct dentry *parent = dentry->d_parent; -		struct dentry *new = d_lookup(parent, &dentry->d_name); -		if (new != NULL) -			dentry = new; -		else -			dentry = ERR_PTR(-ENOENT); +		if ((!d_mountpoint(dentry) && !simple_empty(dentry)) || +		    (dentry->d_inode && S_ISLNK(dentry->d_inode->i_mode))) +			status = -EISDIR; +	} +	spin_unlock(&sbi->fs_lock); -		if (active) -			dput(active); +	return status; +} -		return dentry; -	} +/* Lookups in the root directory */ +static struct dentry *autofs4_lookup(struct inode *dir, struct dentry *dentry, unsigned int flags) +{ +	struct autofs_sb_info *sbi; +	struct autofs_info *ino; +	struct dentry *active; + +	DPRINTK("name = %.*s", dentry->d_name.len, dentry->d_name.name); + +	/* File name too long to exist */ +	if (dentry->d_name.len > NAME_MAX) +		return ERR_PTR(-ENAMETOOLONG); + +	sbi = autofs4_sbi(dir->i_sb); -	if (active) +	DPRINTK("pid = %u, pgrp = %u, catatonic = %d, oz_mode = %d", +		current->pid, task_pgrp_nr(current), sbi->catatonic, +		autofs4_oz_mode(sbi)); + +	active = autofs4_lookup_active(dentry); +	if (active) {  		return active; +	} else { +		/* +		 * A dentry that is not within the root can never trigger a +		 * mount operation, unless the directory already exists, so we +		 * can return fail immediately.  The daemon however does need +		 * to create directories within the file system. +		 */ +		if (!autofs4_oz_mode(sbi) && !IS_ROOT(dentry->d_parent)) +			return ERR_PTR(-ENOENT); + +		/* Mark entries in the root as mount triggers */ +		if (autofs_type_indirect(sbi->type) && IS_ROOT(dentry->d_parent)) +			__managed_dentry_set_managed(dentry); + +		ino = autofs4_new_ino(sbi); +		if (!ino) +			return ERR_PTR(-ENOMEM); + +		dentry->d_fsdata = ino; +		ino->dentry = dentry; + +		autofs4_add_active(dentry); +		d_instantiate(dentry, NULL); +	}  	return NULL;  } @@ -664,6 +523,7 @@ static int autofs4_dir_symlink(struct inode *dir,  	struct autofs_info *ino = autofs4_dentry_ino(dentry);  	struct autofs_info *p_ino;  	struct inode *inode; +	size_t size = strlen(symname);  	char *cp;  	DPRINTK("%s <- %.*s", symname, @@ -672,45 +532,35 @@ static int autofs4_dir_symlink(struct inode *dir,  	if (!autofs4_oz_mode(sbi))  		return -EACCES; -	ino = autofs4_init_ino(ino, sbi, S_IFLNK | 0555); -	if (!ino) -		return -ENOMEM; +	BUG_ON(!ino); + +	autofs4_clean_ino(ino);  	autofs4_del_active(dentry); -	ino->size = strlen(symname); -	cp = kmalloc(ino->size + 1, GFP_KERNEL); -	if (!cp) { -		if (!dentry->d_fsdata) -			kfree(ino); +	cp = kmalloc(size + 1, GFP_KERNEL); +	if (!cp)  		return -ENOMEM; -	}  	strcpy(cp, symname); -	inode = autofs4_get_inode(dir->i_sb, ino); +	inode = autofs4_get_inode(dir->i_sb, S_IFLNK | 0555);  	if (!inode) {  		kfree(cp);  		if (!dentry->d_fsdata)  			kfree(ino);  		return -ENOMEM;  	} +	inode->i_private = cp; +	inode->i_size = size;  	d_add(dentry, inode); -	if (dir == dir->i_sb->s_root->d_inode) -		dentry->d_op = &autofs4_root_dentry_operations; -	else -		dentry->d_op = &autofs4_dentry_operations; - -	dentry->d_fsdata = ino; -	ino->dentry = dget(dentry); +	dget(dentry);  	atomic_inc(&ino->count);  	p_ino = autofs4_dentry_ino(dentry->d_parent); -	if (p_ino && dentry->d_parent != dentry) +	if (p_ino && !IS_ROOT(dentry))  		atomic_inc(&p_ino->count); -	ino->inode = inode; -	ino->u.symlink = cp;  	dir->i_mtime = CURRENT_TIME;  	return 0; @@ -739,11 +589,11 @@ static int autofs4_dir_unlink(struct inode *dir, struct dentry *dentry)  	/* This allows root to remove symlinks */  	if (!autofs4_oz_mode(sbi) && !capable(CAP_SYS_ADMIN)) -		return -EACCES; +		return -EPERM;  	if (atomic_dec_and_test(&ino->count)) {  		p_ino = autofs4_dentry_ino(dentry->d_parent); -		if (p_ino && dentry->d_parent != dentry) +		if (p_ino && !IS_ROOT(dentry))  			atomic_dec(&p_ino->count);  	}  	dput(ino->dentry); @@ -753,16 +603,66 @@ static int autofs4_dir_unlink(struct inode *dir, struct dentry *dentry)  	dir->i_mtime = CURRENT_TIME; -	spin_lock(&dcache_lock); -	autofs4_add_expiring(dentry); -	spin_lock(&dentry->d_lock); -	__d_drop(dentry); -	spin_unlock(&dentry->d_lock); -	spin_unlock(&dcache_lock); +	spin_lock(&sbi->lookup_lock); +	__autofs4_add_expiring(dentry); +	d_drop(dentry); +	spin_unlock(&sbi->lookup_lock);  	return 0;  } +/* + * Version 4 of autofs provides a pseudo direct mount implementation + * that relies on directories at the leaves of a directory tree under + * an indirect mount to trigger mounts. To allow for this we need to + * set the DMANAGED_AUTOMOUNT and DMANAGED_TRANSIT flags on the leaves + * of the directory tree. There is no need to clear the automount flag + * following a mount or restore it after an expire because these mounts + * are always covered. However, it is necessary to ensure that these + * flags are clear on non-empty directories to avoid unnecessary calls + * during path walks. + */ +static void autofs_set_leaf_automount_flags(struct dentry *dentry) +{ +	struct dentry *parent; + +	/* root and dentrys in the root are already handled */ +	if (IS_ROOT(dentry->d_parent)) +		return; + +	managed_dentry_set_managed(dentry); + +	parent = dentry->d_parent; +	/* only consider parents below dentrys in the root */ +	if (IS_ROOT(parent->d_parent)) +		return; +	managed_dentry_clear_managed(parent); +	return; +} + +static void autofs_clear_leaf_automount_flags(struct dentry *dentry) +{ +	struct list_head *d_child; +	struct dentry *parent; + +	/* flags for dentrys in the root are handled elsewhere */ +	if (IS_ROOT(dentry->d_parent)) +		return; + +	managed_dentry_clear_managed(dentry); + +	parent = dentry->d_parent; +	/* only consider parents below dentrys in the root */ +	if (IS_ROOT(parent->d_parent)) +		return; +	d_child = &dentry->d_u.d_child; +	/* Set parent managed if it's becoming empty */ +	if (d_child->next == &parent->d_subdirs && +	    d_child->prev == &parent->d_subdirs) +		managed_dentry_set_managed(parent); +	return; +} +  static int autofs4_dir_rmdir(struct inode *dir, struct dentry *dentry)  {  	struct autofs_sb_info *sbi = autofs4_sbi(dir->i_sb); @@ -775,16 +675,17 @@ static int autofs4_dir_rmdir(struct inode *dir, struct dentry *dentry)  	if (!autofs4_oz_mode(sbi))  		return -EACCES; -	spin_lock(&dcache_lock); -	if (!list_empty(&dentry->d_subdirs)) { -		spin_unlock(&dcache_lock); +	spin_lock(&sbi->lookup_lock); +	if (!simple_empty(dentry)) { +		spin_unlock(&sbi->lookup_lock);  		return -ENOTEMPTY;  	} -	autofs4_add_expiring(dentry); -	spin_lock(&dentry->d_lock); -	__d_drop(dentry); -	spin_unlock(&dentry->d_lock); -	spin_unlock(&dcache_lock); +	__autofs4_add_expiring(dentry); +	d_drop(dentry); +	spin_unlock(&sbi->lookup_lock); + +	if (sbi->version < 5) +		autofs_clear_leaf_automount_flags(dentry);  	if (atomic_dec_and_test(&ino->count)) {  		p_ino = autofs4_dentry_ino(dentry->d_parent); @@ -801,7 +702,7 @@ static int autofs4_dir_rmdir(struct inode *dir, struct dentry *dentry)  	return 0;  } -static int autofs4_dir_mkdir(struct inode *dir, struct dentry *dentry, int mode) +static int autofs4_dir_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)  {  	struct autofs_sb_info *sbi = autofs4_sbi(dir->i_sb);  	struct autofs_info *ino = autofs4_dentry_ino(dentry); @@ -814,32 +715,25 @@ static int autofs4_dir_mkdir(struct inode *dir, struct dentry *dentry, int mode)  	DPRINTK("dentry %p, creating %.*s",  		dentry, dentry->d_name.len, dentry->d_name.name); -	ino = autofs4_init_ino(ino, sbi, S_IFDIR | 0555); -	if (!ino) -		return -ENOMEM; +	BUG_ON(!ino); + +	autofs4_clean_ino(ino);  	autofs4_del_active(dentry); -	inode = autofs4_get_inode(dir->i_sb, ino); -	if (!inode) { -		if (!dentry->d_fsdata) -			kfree(ino); +	inode = autofs4_get_inode(dir->i_sb, S_IFDIR | 0555); +	if (!inode)  		return -ENOMEM; -	}  	d_add(dentry, inode); -	if (dir == dir->i_sb->s_root->d_inode) -		dentry->d_op = &autofs4_root_dentry_operations; -	else -		dentry->d_op = &autofs4_dentry_operations; +	if (sbi->version < 5) +		autofs_set_leaf_automount_flags(dentry); -	dentry->d_fsdata = ino; -	ino->dentry = dget(dentry); +	dget(dentry);  	atomic_inc(&ino->count);  	p_ino = autofs4_dentry_ino(dentry->d_parent); -	if (p_ino && dentry->d_parent != dentry) +	if (p_ino && !IS_ROOT(dentry))  		atomic_inc(&p_ino->count); -	ino->inode = inode;  	inc_nlink(dir);  	dir->i_mtime = CURRENT_TIME; @@ -921,8 +815,7 @@ static inline int autofs4_ask_umount(struct vfsmount *mnt, int __user *p)  int is_autofs4_dentry(struct dentry *dentry)  {  	return dentry && dentry->d_inode && -		(dentry->d_op == &autofs4_root_dentry_operations || -		 dentry->d_op == &autofs4_dentry_operations) && +		dentry->d_op == &autofs4_dentry_operations &&  		dentry->d_fsdata != NULL;  } @@ -980,35 +873,25 @@ static int autofs4_root_ioctl_unlocked(struct inode *inode, struct file *filp,  	}  } -static DEFINE_MUTEX(autofs4_ioctl_mutex); -  static long autofs4_root_ioctl(struct file *filp,  			       unsigned int cmd, unsigned long arg)  { -	long ret; -	struct inode *inode = filp->f_dentry->d_inode; - -	mutex_lock(&autofs4_ioctl_mutex); -	ret = autofs4_root_ioctl_unlocked(inode, filp, cmd, arg); -	mutex_unlock(&autofs4_ioctl_mutex); - -	return ret; +	struct inode *inode = file_inode(filp); +	return autofs4_root_ioctl_unlocked(inode, filp, cmd, arg);  }  #ifdef CONFIG_COMPAT  static long autofs4_root_compat_ioctl(struct file *filp,  			     unsigned int cmd, unsigned long arg)  { -	struct inode *inode = filp->f_path.dentry->d_inode; +	struct inode *inode = file_inode(filp);  	int ret; -	mutex_lock(&autofs4_ioctl_mutex);  	if (cmd == AUTOFS_IOC_READY || cmd == AUTOFS_IOC_FAIL)  		ret = autofs4_root_ioctl_unlocked(inode, filp, cmd, arg);  	else  		ret = autofs4_root_ioctl_unlocked(inode, filp, cmd,  			(unsigned long)compat_ptr(arg)); -	mutex_unlock(&autofs4_ioctl_mutex);  	return ret;  } diff --git a/fs/autofs4/symlink.c b/fs/autofs4/symlink.c index b4ea82934d2..1e8ea192be2 100644 --- a/fs/autofs4/symlink.c +++ b/fs/autofs4/symlink.c @@ -14,8 +14,11 @@  static void *autofs4_follow_link(struct dentry *dentry, struct nameidata *nd)  { +	struct autofs_sb_info *sbi = autofs4_sbi(dentry->d_sb);  	struct autofs_info *ino = autofs4_dentry_ino(dentry); -	nd_set_link(nd, (char *)ino->u.symlink); +	if (ino && !autofs4_oz_mode(sbi)) +		ino->last_used = jiffies; +	nd_set_link(nd, dentry->d_inode->i_private);  	return NULL;  } diff --git a/fs/autofs4/waitq.c b/fs/autofs4/waitq.c index 2341375386f..116fd38ee47 100644 --- a/fs/autofs4/waitq.c +++ b/fs/autofs4/waitq.c @@ -42,10 +42,8 @@ void autofs4_catatonic_mode(struct autofs_sb_info *sbi)  	while (wq) {  		nwq = wq->next;  		wq->status = -ENOENT; /* Magic is gone - report failure */ -		if (wq->name.name) { -			kfree(wq->name.name); -			wq->name.name = NULL; -		} +		kfree(wq->name.name); +		wq->name.name = NULL;  		wq->wait_ctr--;  		wake_up_interruptible(&wq->queue);  		wq = nwq; @@ -56,26 +54,27 @@ void autofs4_catatonic_mode(struct autofs_sb_info *sbi)  	mutex_unlock(&sbi->wq_mutex);  } -static int autofs4_write(struct file *file, const void *addr, int bytes) +static int autofs4_write(struct autofs_sb_info *sbi, +			 struct file *file, const void *addr, int bytes)  {  	unsigned long sigpipe, flags;  	mm_segment_t fs;  	const char *data = (const char *)addr;  	ssize_t wr = 0; -	/** WARNING: this is not safe for writing more than PIPE_BUF bytes! **/ -  	sigpipe = sigismember(¤t->pending.signal, SIGPIPE);  	/* Save pointer to user space and point back to kernel space */  	fs = get_fs();  	set_fs(KERNEL_DS); +	mutex_lock(&sbi->pipe_mutex);  	while (bytes &&  	       (wr = file->f_op->write(file,data,bytes,&file->f_pos)) > 0) {  		data += wr;  		bytes -= wr;  	} +	mutex_unlock(&sbi->pipe_mutex);  	set_fs(fs); @@ -104,12 +103,13 @@ static void autofs4_notify_daemon(struct autofs_sb_info *sbi,  	size_t pktsz;  	DPRINTK("wait id = 0x%08lx, name = %.*s, type=%d", -		wq->wait_queue_token, wq->name.len, wq->name.name, type); +		(unsigned long) wq->wait_queue_token, wq->name.len, wq->name.name, type);  	memset(&pkt,0,sizeof pkt); /* For security reasons */  	pkt.hdr.proto_version = sbi->version;  	pkt.hdr.type = type; +  	switch (type) {  	/* Kernel protocol v4 missing and expire packets */  	case autofs_ptype_missing: @@ -146,6 +146,7 @@ static void autofs4_notify_daemon(struct autofs_sb_info *sbi,  	case autofs_ptype_expire_direct:  	{  		struct autofs_v5_packet *packet = &pkt.v5_pkt.v5_packet; +		struct user_namespace *user_ns = sbi->pipe->f_cred->user_ns;  		pktsz = sizeof(*packet); @@ -155,30 +156,25 @@ static void autofs4_notify_daemon(struct autofs_sb_info *sbi,  		packet->name[wq->name.len] = '\0';  		packet->dev = wq->dev;  		packet->ino = wq->ino; -		packet->uid = wq->uid; -		packet->gid = wq->gid; +		packet->uid = from_kuid_munged(user_ns, wq->uid); +		packet->gid = from_kgid_munged(user_ns, wq->gid);  		packet->pid = wq->pid;  		packet->tgid = wq->tgid;  		break;  	}  	default:  		printk("autofs4_notify_daemon: bad type %d!\n", type); +		mutex_unlock(&sbi->wq_mutex);  		return;  	} -	/* Check if we have become catatonic */ -	mutex_lock(&sbi->wq_mutex); -	if (!sbi->catatonic) { -		pipe = sbi->pipe; -		get_file(pipe); -	} +	pipe = get_file(sbi->pipe); +  	mutex_unlock(&sbi->wq_mutex); -	if (pipe) { -		if (autofs4_write(pipe, &pkt, pktsz)) -			autofs4_catatonic_mode(sbi); -		fput(pipe); -	} +	if (autofs4_write(sbi, pipe, &pkt, pktsz)) +		autofs4_catatonic_mode(sbi); +	fput(pipe);  }  static int autofs4_getpath(struct autofs_sb_info *sbi, @@ -186,16 +182,26 @@ static int autofs4_getpath(struct autofs_sb_info *sbi,  {  	struct dentry *root = sbi->sb->s_root;  	struct dentry *tmp; -	char *buf = *name; +	char *buf;  	char *p; -	int len = 0; +	int len; +	unsigned seq; + +rename_retry: +	buf = *name; +	len = 0; -	spin_lock(&dcache_lock); +	seq = read_seqbegin(&rename_lock); +	rcu_read_lock(); +	spin_lock(&sbi->fs_lock);  	for (tmp = dentry ; tmp != root ; tmp = tmp->d_parent)  		len += tmp->d_name.len + 1;  	if (!len || --len > NAME_MAX) { -		spin_unlock(&dcache_lock); +		spin_unlock(&sbi->fs_lock); +		rcu_read_unlock(); +		if (read_seqretry(&rename_lock, seq)) +			goto rename_retry;  		return 0;  	} @@ -208,7 +214,10 @@ static int autofs4_getpath(struct autofs_sb_info *sbi,  		p -= tmp->d_name.len;  		strncpy(p, tmp->d_name.name, tmp->d_name.len);  	} -	spin_unlock(&dcache_lock); +	spin_unlock(&sbi->fs_lock); +	rcu_read_unlock(); +	if (read_seqretry(&rename_lock, seq)) +		goto rename_retry;  	return len;  } @@ -244,6 +253,9 @@ static int validate_request(struct autofs_wait_queue **wait,  	struct autofs_wait_queue *wq;  	struct autofs_info *ino; +	if (sbi->catatonic) +		return -ENOENT; +  	/* Wait in progress, continue; */  	wq = autofs4_find_wait(sbi, qstr);  	if (wq) { @@ -276,6 +288,9 @@ static int validate_request(struct autofs_wait_queue **wait,  			if (mutex_lock_interruptible(&sbi->wq_mutex))  				return -EINTR; +			if (sbi->catatonic) +				return -ENOENT; +  			wq = autofs4_find_wait(sbi, qstr);  			if (wq) {  				*wait = wq; @@ -296,6 +311,9 @@ static int validate_request(struct autofs_wait_queue **wait,  	 * completed while we waited on the mutex ...  	 */  	if (notify == NFY_MOUNT) { +		struct dentry *new = NULL; +		int valid = 1; +  		/*  		 * If the dentry was successfully mounted while we slept  		 * on the wait queue mutex we can return success. If it @@ -303,8 +321,20 @@ static int validate_request(struct autofs_wait_queue **wait,  		 * a multi-mount with no mount at it's base) we can  		 * continue on and create a new request.  		 */ +		if (!IS_ROOT(dentry)) { +			if (dentry->d_inode && d_unhashed(dentry)) { +				struct dentry *parent = dentry->d_parent; +				new = d_lookup(parent, &dentry->d_name); +				if (new) +					dentry = new; +			} +		}  		if (have_submounts(dentry)) -			return 0; +			valid = 0; + +		if (new) +			dput(new); +		return valid;  	}  	return 1; @@ -317,11 +347,23 @@ int autofs4_wait(struct autofs_sb_info *sbi, struct dentry *dentry,  	struct qstr qstr;  	char *name;  	int status, ret, type; +	pid_t pid; +	pid_t tgid;  	/* In catatonic mode, we don't wait for nobody */  	if (sbi->catatonic)  		return -ENOENT; +	/* +	 * Try translating pids to the namespace of the daemon. +	 * +	 * Zero means failure: we are in an unrelated pid namespace. +	 */ +	pid = task_pid_nr_ns(current, ns_of_pid(sbi->oz_pgrp)); +	tgid = task_tgid_nr_ns(current, ns_of_pid(sbi->oz_pgrp)); +	if (pid == 0 || tgid == 0) +		return -ENOENT; +  	if (!dentry->d_inode) {  		/*  		 * A wait for a negative dentry is invalid for certain @@ -361,7 +403,7 @@ int autofs4_wait(struct autofs_sb_info *sbi, struct dentry *dentry,  	ret = validate_request(&wq, sbi, &qstr, dentry, notify);  	if (ret <= 0) { -		if (ret == 0) +		if (ret != -EINTR)  			mutex_unlock(&sbi->wq_mutex);  		kfree(qstr.name);  		return ret; @@ -387,11 +429,10 @@ int autofs4_wait(struct autofs_sb_info *sbi, struct dentry *dentry,  		wq->ino = autofs4_get_ino(sbi);  		wq->uid = current_uid();  		wq->gid = current_gid(); -		wq->pid = current->pid; -		wq->tgid = current->tgid; +		wq->pid = pid; +		wq->tgid = tgid;  		wq->status = -EINTR; /* Status return if interrupted */  		wq->wait_ctr = 2; -		mutex_unlock(&sbi->wq_mutex);  		if (sbi->version < 5) {  			if (notify == NFY_MOUNT) @@ -413,15 +454,15 @@ int autofs4_wait(struct autofs_sb_info *sbi, struct dentry *dentry,  			(unsigned long) wq->wait_queue_token, wq->name.len,  			wq->name.name, notify); -		/* autofs4_notify_daemon() may block */ +		/* autofs4_notify_daemon() may block; it will unlock ->wq_mutex */  		autofs4_notify_daemon(sbi, wq, type);  	} else {  		wq->wait_ctr++; -		mutex_unlock(&sbi->wq_mutex); -		kfree(qstr.name);  		DPRINTK("existing wait id = 0x%08lx, name = %.*s, nfy=%d",  			(unsigned long) wq->wait_queue_token, wq->name.len,  			wq->name.name, notify); +		mutex_unlock(&sbi->wq_mutex); +		kfree(qstr.name);  	}  	/*  | 
