fs/autofs4/inode.c - kernel/quantenna - Git at Google

 /*
  * 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>

 struct autofs_info *autofs4_new_ino(struct autofs_sb_info *sbi)
 {
 	struct autofs_info *ino;

 	ino = kzalloc(sizeof(*ino), GFP_KERNEL);
 	if (ino) {
 		INIT_LIST_HEAD(&ino->active);
 		INIT_LIST_HEAD(&ino->expiring);
 		ino->last_used = jiffies;
 		ino->sbi = sbi;
 	}
 	return ino;
 }

 void autofs4_clean_ino(struct autofs_info *ino)
 {
 	ino->uid = GLOBAL_ROOT_UID;
 	ino->gid = GLOBAL_ROOT_GID;
 	ino->last_used = jiffies;
 }

 void autofs4_free_ino(struct autofs_info *ino)
 {
 	kfree(ino);
 }

 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) {
 		/* Free wait queues, close pipe */
 		autofs4_catatonic_mode(sbi);
 		put_pid(sbi->oz_pgrp);
 	}

 	pr_debug("shutting down\n");
 	kill_litter_super(sb);
 	if (sbi)
 		kfree_rcu(sbi, rcu);
 }

 static int autofs4_show_options(struct seq_file *m, struct dentry *root)
 {
 	struct autofs_sb_info *sbi = autofs4_sbi(root->d_sb);
 	struct inode *root_inode = d_inode(root->d_sb->s_root);

 	if (!sbi)
 		return 0;

 	seq_printf(m, ",fd=%d", sbi->pipefd);
 	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);

 	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");
 #ifdef CONFIG_CHECKPOINT_RESTORE
 	if (sbi->pipe)
 		seq_printf(m, ",pipe_ino=%ld", sbi->pipe->f_inode->i_ino);
 	else
 		seq_printf(m, ",pipe_ino=-1");
 #endif
 	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,
 	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, 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];
 	int option;

 	*uid = current_uid();
 	*gid = current_gid();

 	*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 = make_kuid(current_user_ns(), option);
 			if (!uid_valid(*uid))
 				return 1;
 			break;
 		case Opt_gid:
 			if (match_int(args, &option))
 				return 1;
 			*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))
 				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);
 }

 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;
 	int pgrp = 0;
 	bool pgrp_set = false;
 	int ret = -EINVAL;

 	sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
 	if (!sbi)
 		return -ENOMEM;
 	pr_debug("starting up, sbi = %p\n", 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 = NULL;
 	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);
 	mutex_init(&sbi->pipe_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_d_op = &autofs4_dentry_operations;
 	s->s_time_gran = 1;

 	/*
 	 * Get the root inode and dentry, but defer checking for errors.
 	 */
 	ino = autofs4_new_ino(sbi);
 	if (!ino) {
 		ret = -ENOMEM;
 		goto fail_free;
 	}
 	root_inode = autofs4_get_inode(s, S_IFDIR | 0755);
 	root = d_make_root(root_inode);
 	if (!root)
 		goto fail_ino;
 	pipe = NULL;

 	root->d_fsdata = ino;

 	/* Can this call block? */
 	if (parse_options(data, &pipefd, &root_inode->i_uid, &root_inode->i_gid,
 			  &pgrp, &pgrp_set, &sbi->type, &sbi->min_proto,
 			  &sbi->max_proto)) {
 		pr_err("called with bogus options\n");
 		goto fail_dput;
 	}

 	if (pgrp_set) {
 		sbi->oz_pgrp = find_get_pid(pgrp);
 		if (!sbi->oz_pgrp) {
 			pr_err("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 = &autofs4_dir_inode_operations;

 	/* Couldn't this be tested earlier? */
 	if (sbi->max_proto < AUTOFS_MIN_PROTO_VERSION ||
 	    sbi->min_proto > AUTOFS_MAX_PROTO_VERSION) {
 		pr_err("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;

 	pr_debug("pipe fd = %d, pgrp = %u\n", pipefd, pid_nr(sbi->oz_pgrp));
 	pipe = fget(pipefd);

 	if (!pipe) {
 		pr_err("could not open pipe file descriptor\n");
 		goto fail_dput;
 	}
 	ret = autofs_prepare_pipe(pipe);
 	if (ret < 0)
 		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:
 	pr_err("pipe file descriptor does not contain proper ops\n");
 	fput(pipe);
 	/* fall through */
 fail_dput:
 	dput(root);
 	goto fail_free;
 fail_ino:
 	kfree(ino);
 fail_free:
 	put_pid(sbi->oz_pgrp);
 	kfree(sbi);
 	s->s_fs_info = NULL;
 	return ret;
 }

 struct inode *autofs4_get_inode(struct super_block *sb, umode_t mode)
 {
 	struct inode *inode = new_inode(sb);

 	if (inode == NULL)
 		return NULL;

 	inode->i_mode = mode;
 	if (sb->s_root) {
 		inode->i_uid = d_inode(sb->s_root)->i_uid;
 		inode->i_gid = d_inode(sb->s_root)->i_gid;
 	}
 	inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME;
 	inode->i_ino = get_next_ino();

 	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(mode)) {
 		inode->i_op = &autofs4_symlink_inode_operations;
 	}

 	return inode;
 }
	/*
	* 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>

	struct autofs_info autofs4_new_ino(struct autofs_sb_info sbi)
	{
	struct autofs_info *ino;

	ino = kzalloc(sizeof(*ino), GFP_KERNEL);
	if (ino) {
	INIT_LIST_HEAD(&ino->active);
	INIT_LIST_HEAD(&ino->expiring);
	ino->last_used = jiffies;
	ino->sbi = sbi;
	}
	return ino;
	}

	void autofs4_clean_ino(struct autofs_info *ino)
	{
	ino->uid = GLOBAL_ROOT_UID;
	ino->gid = GLOBAL_ROOT_GID;
	ino->last_used = jiffies;
	}

	void autofs4_free_ino(struct autofs_info *ino)
	{
	kfree(ino);
	}

	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) {
	/* Free wait queues, close pipe */
	autofs4_catatonic_mode(sbi);
	put_pid(sbi->oz_pgrp);
	}

	pr_debug("shutting down\n");
	kill_litter_super(sb);
	if (sbi)
	kfree_rcu(sbi, rcu);
	}

	static int autofs4_show_options(struct seq_file m, struct dentry root)
	{
	struct autofs_sb_info *sbi = autofs4_sbi(root->d_sb);
	struct inode *root_inode = d_inode(root->d_sb->s_root);

	if (!sbi)
	return 0;

	seq_printf(m, ",fd=%d", sbi->pipefd);
	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);

	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");
	#ifdef CONFIG_CHECKPOINT_RESTORE
	if (sbi->pipe)
	seq_printf(m, ",pipe_ino=%ld", sbi->pipe->f_inode->i_ino);
	else
	seq_printf(m, ",pipe_ino=-1");
	#endif
	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,
	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, 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];
	int option;

	*uid = current_uid();
	*gid = current_gid();

	*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 = make_kuid(current_user_ns(), option);
	if (!uid_valid(*uid))
	return 1;
	break;
	case Opt_gid:
	if (match_int(args, &option))
	return 1;
	*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))
	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);
	}

	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;
	int pgrp = 0;
	bool pgrp_set = false;
	int ret = -EINVAL;

	sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
	if (!sbi)
	return -ENOMEM;
	pr_debug("starting up, sbi = %p\n", 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 = NULL;
	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);
	mutex_init(&sbi->pipe_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_d_op = &autofs4_dentry_operations;
	s->s_time_gran = 1;

	/*
	* Get the root inode and dentry, but defer checking for errors.
	*/
	ino = autofs4_new_ino(sbi);
	if (!ino) {
	ret = -ENOMEM;
	goto fail_free;
	}
	root_inode = autofs4_get_inode(s, S_IFDIR \| 0755);
	root = d_make_root(root_inode);
	if (!root)
	goto fail_ino;
	pipe = NULL;

	root->d_fsdata = ino;

	/* Can this call block? */
	if (parse_options(data, &pipefd, &root_inode->i_uid, &root_inode->i_gid,
	&pgrp, &pgrp_set, &sbi->type, &sbi->min_proto,
	&sbi->max_proto)) {
	pr_err("called with bogus options\n");
	goto fail_dput;
	}

	if (pgrp_set) {
	sbi->oz_pgrp = find_get_pid(pgrp);
	if (!sbi->oz_pgrp) {
	pr_err("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 = &autofs4_dir_inode_operations;

	/* Couldn't this be tested earlier? */
	if (sbi->max_proto < AUTOFS_MIN_PROTO_VERSION \|\|
	sbi->min_proto > AUTOFS_MAX_PROTO_VERSION) {
	pr_err("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;

	pr_debug("pipe fd = %d, pgrp = %u\n", pipefd, pid_nr(sbi->oz_pgrp));
	pipe = fget(pipefd);

	if (!pipe) {
	pr_err("could not open pipe file descriptor\n");
	goto fail_dput;
	}
	ret = autofs_prepare_pipe(pipe);
	if (ret < 0)
	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:
	pr_err("pipe file descriptor does not contain proper ops\n");
	fput(pipe);
	/* fall through */
	fail_dput:
	dput(root);
	goto fail_free;
	fail_ino:
	kfree(ino);
	fail_free:
	put_pid(sbi->oz_pgrp);
	kfree(sbi);
	s->s_fs_info = NULL;
	return ret;
	}

	struct inode autofs4_get_inode(struct super_block sb, umode_t mode)
	{
	struct inode *inode = new_inode(sb);

	if (inode == NULL)
	return NULL;

	inode->i_mode = mode;
	if (sb->s_root) {
	inode->i_uid = d_inode(sb->s_root)->i_uid;
	inode->i_gid = d_inode(sb->s_root)->i_gid;
	}
	inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME;
	inode->i_ino = get_next_ino();

	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(mode)) {
	inode->i_op = &autofs4_symlink_inode_operations;
	}

	return inode;
	}