fs/autofs4/inode.c - kernel/msm-4.9 - Gitiles

 /* -*- c -*- --------------------------------------------------------------- *
  *
  * linux/fs/autofs/inode.c
  *
  *  Copyright 1997-1998 Transmeta Corporation -- All Rights Reserved
  *  Copyright 2005-2006 Ian Kent <raven@themaw.net>
  *
  * This file is part of the Linux kernel and is made available under
  * the terms of the GNU General Public License, version 2, or at your
  * option, any later version, incorporated herein by reference.
  *
  * ------------------------------------------------------------------------- */

 #include <linux/kernel.h>
 #include <linux/slab.h>
 #include <linux/file.h>
 #include <linux/seq_file.h>
 #include <linux/pagemap.h>
 #include <linux/parser.h>
 #include <linux/bitops.h>
 #include <linux/magic.h>
 #include "autofs_i.h"
 #include <linux/module.h>

 static void ino_lnkfree(struct autofs_info *ino)
 {
 	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;
 		INIT_LIST_HEAD(&ino->active);
 		INIT_LIST_HEAD(&ino->expiring);
 		atomic_set(&ino->count, 0);
 	}

 	ino->uid = 0;
 	ino->gid = 0;
 	ino->mode = mode;
 	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);
 }

 /*
  * Deal with the infamous "Busy inodes after umount ..." message.
  *
  * Clean up the dentry tree. This happens with autofs if the user
  * space program goes away due to a SIGKILL, SIGSEGV etc.
  */
 static void autofs4_force_release(struct autofs_sb_info *sbi)
 {
 	struct dentry *this_parent = sbi->sb->s_root;
 	struct list_head *next;

 	if (!sbi->sb->s_root)
 		return;

 	spin_lock(&dcache_lock);
 repeat:
 	next = this_parent->d_subdirs.next;
 resume:
 	while (next != &this_parent->d_subdirs) {
 		struct dentry *dentry = list_entry(next, struct dentry, d_u.d_child);

 		/* Negative dentry - don`t care */
 		if (!simple_positive(dentry)) {
 			next = next->next;
 			continue;
 		}

 		if (!list_empty(&dentry->d_subdirs)) {
 			this_parent = dentry;
 			goto repeat;
 		}

 		next = next->next;
 		spin_unlock(&dcache_lock);

 		DPRINTK("dentry %p %.*s",
 			dentry, (int)dentry->d_name.len, dentry->d_name.name);

 		dput(dentry);
 		spin_lock(&dcache_lock);
 	}

 	if (this_parent != sbi->sb->s_root) {
 		struct dentry *dentry = this_parent;

 		next = this_parent->d_u.d_child.next;
 		this_parent = this_parent->d_parent;
 		spin_unlock(&dcache_lock);
 		DPRINTK("parent dentry %p %.*s",
 			dentry, (int)dentry->d_name.len, dentry->d_name.name);
 		dput(dentry);
 		spin_lock(&dcache_lock);
 		goto resume;
 	}
 	spin_unlock(&dcache_lock);
 }

 void autofs4_kill_sb(struct super_block *sb)
 {
 	struct autofs_sb_info *sbi = autofs4_sbi(sb);

 	/*
 	 * In the event of a failure in get_sb_nodev the superblock
 	 * info is not present so nothing else has been setup, so
 	 * 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);

 	/* Clean up and release dangling references */
 	autofs4_force_release(sbi);

 	sb->s_fs_info = NULL;
 	kfree(sbi);

 out_kill_sb:
 	DPRINTK("shutting down");
 	kill_anon_super(sb);
 }

 static int autofs4_show_options(struct seq_file *m, struct vfsmount *mnt)
 {
 	struct autofs_sb_info *sbi = autofs4_sbi(mnt->mnt_sb);
 	struct inode *root_inode = mnt->mnt_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);
 	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);

 	if (autofs_type_offset(sbi->type))
 		seq_printf(m, ",offset");
 	else if (autofs_type_direct(sbi->type))
 		seq_printf(m, ",direct");
 	else
 		seq_printf(m, ",indirect");

 	return 0;
 }

 static const struct super_operations autofs4_sops = {
 	.statfs		= simple_statfs,
 	.show_options	= autofs4_show_options,
 };

 enum {Opt_err, Opt_fd, Opt_uid, Opt_gid, Opt_pgrp, Opt_minproto, Opt_maxproto,
 	Opt_indirect, Opt_direct, Opt_offset};

 static const match_table_t tokens = {
 	{Opt_fd, "fd=%u"},
 	{Opt_uid, "uid=%u"},
 	{Opt_gid, "gid=%u"},
 	{Opt_pgrp, "pgrp=%u"},
 	{Opt_minproto, "minproto=%u"},
 	{Opt_maxproto, "maxproto=%u"},
 	{Opt_indirect, "indirect"},
 	{Opt_direct, "direct"},
 	{Opt_offset, "offset"},
 	{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)
 {
 	char *p;
 	substring_t args[MAX_OPT_ARGS];
 	int option;

 	*uid = current_uid();
 	*gid = current_gid();
 	*pgrp = task_pgrp_nr(current);

 	*minproto = AUTOFS_MIN_PROTO_VERSION;
 	*maxproto = AUTOFS_MAX_PROTO_VERSION;

 	*pipefd = -1;

 	if (!options)
 		return 1;

 	while ((p = strsep(&options, ",")) != NULL) {
 		int token;
 		if (!*p)
 			continue;

 		token = match_token(p, tokens, args);
 		switch (token) {
 		case Opt_fd:
 			if (match_int(args, pipefd))
 				return 1;
 			break;
 		case Opt_uid:
 			if (match_int(args, &option))
 				return 1;
 			*uid = option;
 			break;
 		case Opt_gid:
 			if (match_int(args, &option))
 				return 1;
 			*gid = option;
 			break;
 		case Opt_pgrp:
 			if (match_int(args, &option))
 				return 1;
 			*pgrp = option;
 			break;
 		case Opt_minproto:
 			if (match_int(args, &option))
 				return 1;
 			*minproto = option;
 			break;
 		case Opt_maxproto:
 			if (match_int(args, &option))
 				return 1;
 			*maxproto = option;
 			break;
 		case Opt_indirect:
 			set_autofs_type_indirect(type);
 			break;
 		case Opt_direct:
 			set_autofs_type_direct(type);
 			break;
 		case Opt_offset:
 			set_autofs_type_offset(type);
 			break;
 		default:
 			return 1;
 		}
 	}
 	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;
 	struct dentry * root;
 	struct file * pipe;
 	int pipefd;
 	struct autofs_sb_info *sbi;
 	struct autofs_info *ino;

 	sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
 	if (!sbi)
 		goto fail_unlock;
 	DPRINTK("starting up, sbi = %p",sbi);

 	s->s_fs_info = sbi;
 	sbi->magic = AUTOFS_SBI_MAGIC;
 	sbi->pipefd = -1;
 	sbi->pipe = NULL;
 	sbi->catatonic = 1;
 	sbi->exp_timeout = 0;
 	sbi->oz_pgrp = task_pgrp_nr(current);
 	sbi->sb = s;
 	sbi->version = 0;
 	sbi->sub_version = 0;
 	set_autofs_type_indirect(&sbi->type);
 	sbi->min_proto = 0;
 	sbi->max_proto = 0;
 	mutex_init(&sbi->wq_mutex);
 	spin_lock_init(&sbi->fs_lock);
 	sbi->queues = NULL;
 	spin_lock_init(&sbi->lookup_lock);
 	INIT_LIST_HEAD(&sbi->active_list);
 	INIT_LIST_HEAD(&sbi->expiring_list);
 	s->s_blocksize = 1024;
 	s->s_blocksize_bits = 10;
 	s->s_magic = AUTOFS_SUPER_MAGIC;
 	s->s_op = &autofs4_sops;
 	s->s_time_gran = 1;

 	/*
 	 * Get the root inode and dentry, but defer checking for errors.
 	 */
 	ino = autofs4_mkroot(sbi);
 	if (!ino)
 		goto fail_free;
 	root_inode = autofs4_get_inode(s, ino);
 	if (!root_inode)
 		goto fail_ino;

 	root = d_alloc_root(root_inode);
 	if (!root)
 		goto fail_iput;
 	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)) {
 		printk("autofs: called with bogus options\n");
 		goto fail_dput;
 	}

 	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;

 	/* Couldn't this be tested earlier? */
 	if (sbi->max_proto < AUTOFS_MIN_PROTO_VERSION ||
 	    sbi->min_proto > AUTOFS_MAX_PROTO_VERSION) {
 		printk("autofs: kernel does not match daemon version "
 		       "daemon (%d, %d) kernel (%d, %d)\n",
 			sbi->min_proto, sbi->max_proto,
 			AUTOFS_MIN_PROTO_VERSION, AUTOFS_MAX_PROTO_VERSION);
 		goto fail_dput;
 	}

 	/* Establish highest kernel protocol version */
 	if (sbi->max_proto > AUTOFS_MAX_PROTO_VERSION)
 		sbi->version = AUTOFS_MAX_PROTO_VERSION;
 	else
 		sbi->version = sbi->max_proto;
 	sbi->sub_version = AUTOFS_PROTO_SUBVERSION;

 	DPRINTK("pipe fd = %d, pgrp = %u", pipefd, 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)
 		goto fail_fput;
 	sbi->pipe = pipe;
 	sbi->pipefd = pipefd;
 	sbi->catatonic = 0;

 	/*
 	 * Success! Install the root dentry now to indicate completion.
 	 */
 	s->s_root = root;
 	return 0;

 	/*
 	 * Failure ... clean up.
 	 */
 fail_fput:
 	printk("autofs: pipe file descriptor does not contain proper ops\n");
 	fput(pipe);
 	/* fall through */
 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:
 	kfree(sbi);
 	s->s_fs_info = NULL;
 fail_unlock:
 	return -EINVAL;
 }

 struct inode *autofs4_get_inode(struct super_block *sb,
 				struct autofs_info *inf)
 {
 	struct inode *inode = new_inode(sb);

 	if (inode == NULL)
 		return NULL;

 	inf->inode = inode;
 	inode->i_mode = inf->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;
 	}
 	inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME;

 	if (S_ISDIR(inf->mode)) {
 		inode->i_nlink = 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;
 		inode->i_op = &autofs4_symlink_inode_operations;
 	}

 	return inode;
 }
	/* -- c -- --------------------------------------------------------------- *
	*
	* linux/fs/autofs/inode.c
	*
	* Copyright 1997-1998 Transmeta Corporation -- All Rights Reserved
	* Copyright 2005-2006 Ian Kent <raven@themaw.net>
	*
	* This file is part of the Linux kernel and is made available under
	* the terms of the GNU General Public License, version 2, or at your
	* option, any later version, incorporated herein by reference.
	*
	* ------------------------------------------------------------------------- */

	#include <linux/kernel.h>
	#include <linux/slab.h>
	#include <linux/file.h>
	#include <linux/seq_file.h>
	#include <linux/pagemap.h>
	#include <linux/parser.h>
	#include <linux/bitops.h>
	#include <linux/magic.h>
	#include "autofs_i.h"
	#include <linux/module.h>

	static void ino_lnkfree(struct autofs_info *ino)
	{
	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;
	INIT_LIST_HEAD(&ino->active);
	INIT_LIST_HEAD(&ino->expiring);
	atomic_set(&ino->count, 0);
	}

	ino->uid = 0;
	ino->gid = 0;
	ino->mode = mode;
	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);
	}

	/*
	* Deal with the infamous "Busy inodes after umount ..." message.
	*
	* Clean up the dentry tree. This happens with autofs if the user
	* space program goes away due to a SIGKILL, SIGSEGV etc.
	*/
	static void autofs4_force_release(struct autofs_sb_info *sbi)
	{
	struct dentry *this_parent = sbi->sb->s_root;
	struct list_head *next;

	if (!sbi->sb->s_root)
	return;

	spin_lock(&dcache_lock);
	repeat:
	next = this_parent->d_subdirs.next;
	resume:
	while (next != &this_parent->d_subdirs) {
	struct dentry *dentry = list_entry(next, struct dentry, d_u.d_child);

	/* Negative dentry - don`t care */
	if (!simple_positive(dentry)) {
	next = next->next;
	continue;
	}

	if (!list_empty(&dentry->d_subdirs)) {
	this_parent = dentry;
	goto repeat;
	}

	next = next->next;
	spin_unlock(&dcache_lock);

	DPRINTK("dentry %p %.*s",
	dentry, (int)dentry->d_name.len, dentry->d_name.name);

	dput(dentry);
	spin_lock(&dcache_lock);
	}

	if (this_parent != sbi->sb->s_root) {
	struct dentry *dentry = this_parent;

	next = this_parent->d_u.d_child.next;
	this_parent = this_parent->d_parent;
	spin_unlock(&dcache_lock);
	DPRINTK("parent dentry %p %.*s",
	dentry, (int)dentry->d_name.len, dentry->d_name.name);
	dput(dentry);
	spin_lock(&dcache_lock);
	goto resume;
	}
	spin_unlock(&dcache_lock);
	}

	void autofs4_kill_sb(struct super_block *sb)
	{
	struct autofs_sb_info *sbi = autofs4_sbi(sb);

	/*
	* In the event of a failure in get_sb_nodev the superblock
	* info is not present so nothing else has been setup, so
	* 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);

	/* Clean up and release dangling references */
	autofs4_force_release(sbi);

	sb->s_fs_info = NULL;
	kfree(sbi);

	out_kill_sb:
	DPRINTK("shutting down");
	kill_anon_super(sb);
	}

	static int autofs4_show_options(struct seq_file m, struct vfsmount mnt)
	{
	struct autofs_sb_info *sbi = autofs4_sbi(mnt->mnt_sb);
	struct inode *root_inode = mnt->mnt_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);
	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);

	if (autofs_type_offset(sbi->type))
	seq_printf(m, ",offset");
	else if (autofs_type_direct(sbi->type))
	seq_printf(m, ",direct");
	else
	seq_printf(m, ",indirect");

	return 0;
	}

	static const struct super_operations autofs4_sops = {
	.statfs = simple_statfs,
	.show_options = autofs4_show_options,
	};

	enum {Opt_err, Opt_fd, Opt_uid, Opt_gid, Opt_pgrp, Opt_minproto, Opt_maxproto,
	Opt_indirect, Opt_direct, Opt_offset};

	static const match_table_t tokens = {
	{Opt_fd, "fd=%u"},
	{Opt_uid, "uid=%u"},
	{Opt_gid, "gid=%u"},
	{Opt_pgrp, "pgrp=%u"},
	{Opt_minproto, "minproto=%u"},
	{Opt_maxproto, "maxproto=%u"},
	{Opt_indirect, "indirect"},
	{Opt_direct, "direct"},
	{Opt_offset, "offset"},
	{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)
	{
	char *p;
	substring_t args[MAX_OPT_ARGS];
	int option;

	*uid = current_uid();
	*gid = current_gid();
	*pgrp = task_pgrp_nr(current);

	*minproto = AUTOFS_MIN_PROTO_VERSION;
	*maxproto = AUTOFS_MAX_PROTO_VERSION;

	*pipefd = -1;

	if (!options)
	return 1;

	while ((p = strsep(&options, ",")) != NULL) {
	int token;
	if (!*p)
	continue;

	token = match_token(p, tokens, args);
	switch (token) {
	case Opt_fd:
	if (match_int(args, pipefd))
	return 1;
	break;
	case Opt_uid:
	if (match_int(args, &option))
	return 1;
	*uid = option;
	break;
	case Opt_gid:
	if (match_int(args, &option))
	return 1;
	*gid = option;
	break;
	case Opt_pgrp:
	if (match_int(args, &option))
	return 1;
	*pgrp = option;
	break;
	case Opt_minproto:
	if (match_int(args, &option))
	return 1;
	*minproto = option;
	break;
	case Opt_maxproto:
	if (match_int(args, &option))
	return 1;
	*maxproto = option;
	break;
	case Opt_indirect:
	set_autofs_type_indirect(type);
	break;
	case Opt_direct:
	set_autofs_type_direct(type);
	break;
	case Opt_offset:
	set_autofs_type_offset(type);
	break;
	default:
	return 1;
	}
	}
	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;
	struct dentry * root;
	struct file * pipe;
	int pipefd;
	struct autofs_sb_info *sbi;
	struct autofs_info *ino;

	sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
	if (!sbi)
	goto fail_unlock;
	DPRINTK("starting up, sbi = %p",sbi);

	s->s_fs_info = sbi;
	sbi->magic = AUTOFS_SBI_MAGIC;
	sbi->pipefd = -1;
	sbi->pipe = NULL;
	sbi->catatonic = 1;
	sbi->exp_timeout = 0;
	sbi->oz_pgrp = task_pgrp_nr(current);
	sbi->sb = s;
	sbi->version = 0;
	sbi->sub_version = 0;
	set_autofs_type_indirect(&sbi->type);
	sbi->min_proto = 0;
	sbi->max_proto = 0;
	mutex_init(&sbi->wq_mutex);
	spin_lock_init(&sbi->fs_lock);
	sbi->queues = NULL;
	spin_lock_init(&sbi->lookup_lock);
	INIT_LIST_HEAD(&sbi->active_list);
	INIT_LIST_HEAD(&sbi->expiring_list);
	s->s_blocksize = 1024;
	s->s_blocksize_bits = 10;
	s->s_magic = AUTOFS_SUPER_MAGIC;
	s->s_op = &autofs4_sops;
	s->s_time_gran = 1;

	/*
	* Get the root inode and dentry, but defer checking for errors.
	*/
	ino = autofs4_mkroot(sbi);
	if (!ino)
	goto fail_free;
	root_inode = autofs4_get_inode(s, ino);
	if (!root_inode)
	goto fail_ino;

	root = d_alloc_root(root_inode);
	if (!root)
	goto fail_iput;
	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)) {
	printk("autofs: called with bogus options\n");
	goto fail_dput;
	}

	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;

	/* Couldn't this be tested earlier? */
	if (sbi->max_proto < AUTOFS_MIN_PROTO_VERSION \|\|
	sbi->min_proto > AUTOFS_MAX_PROTO_VERSION) {
	printk("autofs: kernel does not match daemon version "
	"daemon (%d, %d) kernel (%d, %d)\n",
	sbi->min_proto, sbi->max_proto,
	AUTOFS_MIN_PROTO_VERSION, AUTOFS_MAX_PROTO_VERSION);
	goto fail_dput;
	}

	/* Establish highest kernel protocol version */
	if (sbi->max_proto > AUTOFS_MAX_PROTO_VERSION)
	sbi->version = AUTOFS_MAX_PROTO_VERSION;
	else
	sbi->version = sbi->max_proto;
	sbi->sub_version = AUTOFS_PROTO_SUBVERSION;

	DPRINTK("pipe fd = %d, pgrp = %u", pipefd, 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)
	goto fail_fput;
	sbi->pipe = pipe;
	sbi->pipefd = pipefd;
	sbi->catatonic = 0;

	/*
	* Success! Install the root dentry now to indicate completion.
	*/
	s->s_root = root;
	return 0;

	/*
	* Failure ... clean up.
	*/
	fail_fput:
	printk("autofs: pipe file descriptor does not contain proper ops\n");
	fput(pipe);
	/* fall through */
	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:
	kfree(sbi);
	s->s_fs_info = NULL;
	fail_unlock:
	return -EINVAL;
	}

	struct inode autofs4_get_inode(struct super_block sb,
	struct autofs_info *inf)
	{
	struct inode *inode = new_inode(sb);

	if (inode == NULL)
	return NULL;

	inf->inode = inode;
	inode->i_mode = inf->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;
	}
	inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME;

	if (S_ISDIR(inf->mode)) {
	inode->i_nlink = 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;
	inode->i_op = &autofs4_symlink_inode_operations;
	}

	return inode;
	}