[linux-2.6-block.git] / fs / autofs / inode.c

// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * Copyright 1997-1998 Transmeta Corporation -- All Rights Reserved
 * Copyright 2005-2006 Ian Kent <raven@themaw.net>
 */

#include <linux/seq_file.h>
#include <linux/pagemap.h>

#include "autofs_i.h"

struct autofs_info *autofs_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;
		ino->count = 1;
	}
	return ino;
}

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

void autofs_free_ino(struct autofs_info *ino)
{
	kfree_rcu(ino, rcu);
}

void autofs_kill_sb(struct super_block *sb)
{
	struct autofs_sb_info *sbi = autofs_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 */
		autofs_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 autofs_show_options(struct seq_file *m, struct dentry *root)
{
	struct autofs_sb_info *sbi = autofs_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_puts(m, ",offset");
	else if (autofs_type_direct(sbi->type))
		seq_puts(m, ",direct");
	else
		seq_puts(m, ",indirect");
	if (sbi->flags & AUTOFS_SBI_STRICTEXPIRE)
		seq_puts(m, ",strictexpire");
	if (sbi->flags & AUTOFS_SBI_IGNORE)
		seq_puts(m, ",ignore");
#ifdef CONFIG_CHECKPOINT_RESTORE
	if (sbi->pipe)
		seq_printf(m, ",pipe_ino=%ld", file_inode(sbi->pipe)->i_ino);
	else
		seq_puts(m, ",pipe_ino=-1");
#endif
	return 0;
}

static void autofs_evict_inode(struct inode *inode)
{
	clear_inode(inode);
	kfree(inode->i_private);
}

static const struct super_operations autofs_sops = {
	.statfs		= simple_statfs,
	.show_options	= autofs_show_options,
	.evict_inode	= autofs_evict_inode,
};

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

const struct fs_parameter_spec autofs_param_specs[] = {
	fsparam_flag	("direct",		Opt_direct),
	fsparam_fd	("fd",			Opt_fd),
	fsparam_u32	("gid",			Opt_gid),
	fsparam_flag	("ignore",		Opt_ignore),
	fsparam_flag	("indirect",		Opt_indirect),
	fsparam_u32	("maxproto",		Opt_maxproto),
	fsparam_u32	("minproto",		Opt_minproto),
	fsparam_flag	("offset",		Opt_offset),
	fsparam_u32	("pgrp",		Opt_pgrp),
	fsparam_flag	("strictexpire",	Opt_strictexpire),
	fsparam_u32	("uid",			Opt_uid),
	{}
};

struct autofs_fs_context {
	kuid_t	uid;
	kgid_t	gid;
	int	pgrp;
	bool	pgrp_set;
};

/*
 * Open the fd.  We do it here rather than in get_tree so that it's done in the
 * context of the system call that passed the data and not the one that
 * triggered the superblock creation, lest the fd gets reassigned.
 */
static int autofs_parse_fd(struct fs_context *fc, struct autofs_sb_info *sbi,
			   struct fs_parameter *param,
			   struct fs_parse_result *result)
{
	struct file *pipe;
	int ret;

	if (param->type == fs_value_is_file) {
		/* came through the new api */
		pipe = param->file;
		param->file = NULL;
	} else {
		pipe = fget(result->uint_32);
	}
	if (!pipe) {
		errorf(fc, "could not open pipe file descriptor");
		return -EBADF;
	}

	ret = autofs_check_pipe(pipe);
	if (ret < 0) {
		errorf(fc, "Invalid/unusable pipe");
		if (param->type != fs_value_is_file)
			fput(pipe);
		return -EBADF;
	}

	if (sbi->pipe)
		fput(sbi->pipe);

	sbi->pipefd = result->uint_32;
	sbi->pipe = pipe;

	return 0;
}

static int autofs_parse_param(struct fs_context *fc, struct fs_parameter *param)
{
	struct autofs_fs_context *ctx = fc->fs_private;
	struct autofs_sb_info *sbi = fc->s_fs_info;
	struct fs_parse_result result;
	kuid_t uid;
	kgid_t gid;
	int opt;

	opt = fs_parse(fc, autofs_param_specs, param, &result);
	if (opt < 0)
		return opt;

	switch (opt) {
	case Opt_fd:
		return autofs_parse_fd(fc, sbi, param, &result);
	case Opt_uid:
		uid = make_kuid(current_user_ns(), result.uint_32);
		if (!uid_valid(uid))
			return invalfc(fc, "Invalid uid");
		ctx->uid = uid;
		break;
	case Opt_gid:
		gid = make_kgid(current_user_ns(), result.uint_32);
		if (!gid_valid(gid))
			return invalfc(fc, "Invalid gid");
		ctx->gid = gid;
		break;
	case Opt_pgrp:
		ctx->pgrp = result.uint_32;
		ctx->pgrp_set = true;
		break;
	case Opt_minproto:
		sbi->min_proto = result.uint_32;
		break;
	case Opt_maxproto:
		sbi->max_proto = result.uint_32;
		break;
	case Opt_indirect:
		set_autofs_type_indirect(&sbi->type);
		break;
	case Opt_direct:
		set_autofs_type_direct(&sbi->type);
		break;
	case Opt_offset:
		set_autofs_type_offset(&sbi->type);
		break;
	case Opt_strictexpire:
		sbi->flags |= AUTOFS_SBI_STRICTEXPIRE;
		break;
	case Opt_ignore:
		sbi->flags |= AUTOFS_SBI_IGNORE;
	}

	return 0;
}

static struct autofs_sb_info *autofs_alloc_sbi(void)
{
	struct autofs_sb_info *sbi;

	sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
	if (!sbi)
		return NULL;

	sbi->magic = AUTOFS_SBI_MAGIC;
	sbi->flags = AUTOFS_SBI_CATATONIC;
	sbi->min_proto = AUTOFS_MIN_PROTO_VERSION;
	sbi->max_proto = AUTOFS_MAX_PROTO_VERSION;
	sbi->pipefd = -1;

	set_autofs_type_indirect(&sbi->type);
	mutex_init(&sbi->wq_mutex);
	mutex_init(&sbi->pipe_mutex);
	spin_lock_init(&sbi->fs_lock);
	spin_lock_init(&sbi->lookup_lock);
	INIT_LIST_HEAD(&sbi->active_list);
	INIT_LIST_HEAD(&sbi->expiring_list);

	return sbi;
}

static int autofs_validate_protocol(struct fs_context *fc)
{
	struct autofs_sb_info *sbi = fc->s_fs_info;

	/* Test versions first */
	if (sbi->max_proto < AUTOFS_MIN_PROTO_VERSION ||
	    sbi->min_proto > AUTOFS_MAX_PROTO_VERSION) {
		errorf(fc, "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);
		return -EINVAL;
	}

	/* 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;

	switch (sbi->version) {
	case 4:
		sbi->sub_version = 7;
		break;
	case 5:
		sbi->sub_version = AUTOFS_PROTO_SUBVERSION;
		break;
	default:
		sbi->sub_version = 0;
	}

	return 0;
}

static int autofs_fill_super(struct super_block *s, struct fs_context *fc)
{
	struct autofs_fs_context *ctx = fc->fs_private;
	struct autofs_sb_info *sbi = s->s_fs_info;
	struct inode *root_inode;
	struct dentry *root;
	struct autofs_info *ino;
	int ret = -ENOMEM;

	pr_debug("starting up, sbi = %p\n", sbi);

	sbi->sb = s;
	s->s_blocksize = 1024;
	s->s_blocksize_bits = 10;
	s->s_magic = AUTOFS_SUPER_MAGIC;
	s->s_op = &autofs_sops;
	s->s_d_op = &autofs_dentry_operations;
	s->s_time_gran = 1;

	/*
	 * Get the root inode and dentry, but defer checking for errors.
	 */
	ino = autofs_new_ino(sbi);
	if (!ino)
		goto fail;

	root_inode = autofs_get_inode(s, S_IFDIR | 0755);
	root_inode->i_uid = ctx->uid;
	root_inode->i_gid = ctx->gid;

	root = d_make_root(root_inode);
	if (!root)
		goto fail_ino;

	root->d_fsdata = ino;

	if (ctx->pgrp_set) {
		sbi->oz_pgrp = find_get_pid(ctx->pgrp);
		if (!sbi->oz_pgrp) {
			ret = invalf(fc, "Could not find process group %d",
				     ctx->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 = &autofs_root_operations;
	root_inode->i_op = &autofs_dir_inode_operations;

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

	sbi->flags &= ~AUTOFS_SBI_CATATONIC;

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

	/*
	 * Failure ... clean up.
	 */
fail_dput:
	dput(root);
	goto fail;
fail_ino:
	autofs_free_ino(ino);
fail:
	return ret;
}

/*
 * Validate the parameters and then request a superblock.
 */
static int autofs_get_tree(struct fs_context *fc)
{
	struct autofs_sb_info *sbi = fc->s_fs_info;
	int ret;

	ret = autofs_validate_protocol(fc);
	if (ret)
		return ret;

	if (sbi->pipefd < 0)
		return invalf(fc, "No control pipe specified");

	return get_tree_nodev(fc, autofs_fill_super);
}

static void autofs_free_fc(struct fs_context *fc)
{
	struct autofs_fs_context *ctx = fc->fs_private;
	struct autofs_sb_info *sbi = fc->s_fs_info;

	if (sbi) {
		if (sbi->pipe)
			fput(sbi->pipe);
		kfree(sbi);
	}
	kfree(ctx);
}

static const struct fs_context_operations autofs_context_ops = {
	.free		= autofs_free_fc,
	.parse_param	= autofs_parse_param,
	.get_tree	= autofs_get_tree,
};

/*
 * Set up the filesystem mount context.
 */
int autofs_init_fs_context(struct fs_context *fc)
{
	struct autofs_fs_context *ctx;
	struct autofs_sb_info *sbi;

	ctx = kzalloc(sizeof(struct autofs_fs_context), GFP_KERNEL);
	if (!ctx)
		goto nomem;

	ctx->uid = current_uid();
	ctx->gid = current_gid();

	sbi = autofs_alloc_sbi();
	if (!sbi)
		goto nomem_ctx;

	fc->fs_private = ctx;
	fc->s_fs_info = sbi;
	fc->ops = &autofs_context_ops;
	return 0;

nomem_ctx:
	kfree(ctx);
nomem:
	return -ENOMEM;
}

struct inode *autofs_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_set_ctime_current(inode);
	inode->i_ino = get_next_ino();

	if (S_ISDIR(mode)) {
		set_nlink(inode, 2);
		inode->i_op = &autofs_dir_inode_operations;
		inode->i_fop = &autofs_dir_operations;
	} else if (S_ISLNK(mode)) {
		inode->i_op = &autofs_symlink_inode_operations;
	} else
		WARN_ON(1);

	return inode;
}
Commit	Line	Data
d6910058	1	// SPDX-License-Identifier: GPL-2.0-or-later
ebc921ca IK	2	/*
	3	* Copyright 1997-1998 Transmeta Corporation -- All Rights Reserved
	4	* Copyright 2005-2006 Ian Kent <raven@themaw.net>
ebc921ca IK	5	*/
ebc921ca IK	6
ebc921ca IK	7	#include <linux/seq_file.h>
ebc921ca IK	8	#include <linux/pagemap.h>
6471e938	9
ebc921ca	10	#include "autofs_i.h"
ebc921ca IK	11
	12	struct autofs_info autofs_new_ino(struct autofs_sb_info sbi)
	13	{
	14	struct autofs_info *ino;
	15
	16	ino = kzalloc(sizeof(*ino), GFP_KERNEL);
	17	if (ino) {
	18	INIT_LIST_HEAD(&ino->active);
	19	INIT_LIST_HEAD(&ino->expiring);
	20	ino->last_used = jiffies;
	21	ino->sbi = sbi;
9ccbac76	22	ino->count = 1;
ebc921ca IK	23	}
	24	return ino;
	25	}
	26
	27	void autofs_clean_ino(struct autofs_info *ino)
	28	{
	29	ino->uid = GLOBAL_ROOT_UID;
	30	ino->gid = GLOBAL_ROOT_GID;
	31	ino->last_used = jiffies;
	32	}
	33
	34	void autofs_free_ino(struct autofs_info *ino)
	35	{
ce285c26	36	kfree_rcu(ino, rcu);
ebc921ca IK	37	}
	38
	39	void autofs_kill_sb(struct super_block *sb)
	40	{
	41	struct autofs_sb_info *sbi = autofs_sbi(sb);
	42
	43	/*
	44	* In the event of a failure in get_sb_nodev the superblock
	45	* info is not present so nothing else has been setup, so
	46	* just call kill_anon_super when we are called from
	47	* deactivate_super.
	48	*/
	49	if (sbi) {
	50	/* Free wait queues, close pipe */
	51	autofs_catatonic_mode(sbi);
	52	put_pid(sbi->oz_pgrp);
	53	}
	54
	55	pr_debug("shutting down\n");
	56	kill_litter_super(sb);
	57	if (sbi)
	58	kfree_rcu(sbi, rcu);
	59	}
	60
	61	static int autofs_show_options(struct seq_file m, struct dentry root)
	62	{
	63	struct autofs_sb_info *sbi = autofs_sbi(root->d_sb);
	64	struct inode *root_inode = d_inode(root->d_sb->s_root);
	65
	66	if (!sbi)
	67	return 0;
	68
	69	seq_printf(m, ",fd=%d", sbi->pipefd);
	70	if (!uid_eq(root_inode->i_uid, GLOBAL_ROOT_UID))
	71	seq_printf(m, ",uid=%u",
	72	from_kuid_munged(&init_user_ns, root_inode->i_uid));
	73	if (!gid_eq(root_inode->i_gid, GLOBAL_ROOT_GID))
	74	seq_printf(m, ",gid=%u",
	75	from_kgid_munged(&init_user_ns, root_inode->i_gid));
	76	seq_printf(m, ",pgrp=%d", pid_vnr(sbi->oz_pgrp));
	77	seq_printf(m, ",timeout=%lu", sbi->exp_timeout/HZ);
	78	seq_printf(m, ",minproto=%d", sbi->min_proto);
	79	seq_printf(m, ",maxproto=%d", sbi->max_proto);
	80
	81	if (autofs_type_offset(sbi->type))
874d22d6	82	seq_puts(m, ",offset");
ebc921ca	83	else if (autofs_type_direct(sbi->type))
874d22d6	84	seq_puts(m, ",direct");
ebc921ca	85	else
874d22d6	86	seq_puts(m, ",indirect");
f5162216	87	if (sbi->flags & AUTOFS_SBI_STRICTEXPIRE)
874d22d6	88	seq_puts(m, ",strictexpire");
60d6d04c	89	if (sbi->flags & AUTOFS_SBI_IGNORE)
874d22d6	90	seq_puts(m, ",ignore");
ebc921ca IK	91	#ifdef CONFIG_CHECKPOINT_RESTORE
	92	if (sbi->pipe)
	93	seq_printf(m, ",pipe_ino=%ld", file_inode(sbi->pipe)->i_ino);
	94	else
874d22d6	95	seq_puts(m, ",pipe_ino=-1");
ebc921ca IK	96	#endif
	97	return 0;
	98	}
	99
	100	static void autofs_evict_inode(struct inode *inode)
	101	{
	102	clear_inode(inode);
	103	kfree(inode->i_private);
	104	}
	105
	106	static const struct super_operations autofs_sops = {
	107	.statfs = simple_statfs,
	108	.show_options = autofs_show_options,
	109	.evict_inode = autofs_evict_inode,
	110	};
	111
7efd93ea	112	enum {
7efd93ea IK	113	Opt_direct,
	114	Opt_fd,
	115	Opt_gid,
	116	Opt_ignore,
	117	Opt_indirect,
	118	Opt_maxproto,
	119	Opt_minproto,
	120	Opt_offset,
	121	Opt_pgrp,
	122	Opt_strictexpire,
	123	Opt_uid,
	124	};
ebc921ca	125
e6ec453b IK	126	const struct fs_parameter_spec autofs_param_specs[] = {
	127	fsparam_flag ("direct", Opt_direct),
	128	fsparam_fd ("fd", Opt_fd),
	129	fsparam_u32 ("gid", Opt_gid),
	130	fsparam_flag ("ignore", Opt_ignore),
	131	fsparam_flag ("indirect", Opt_indirect),
	132	fsparam_u32 ("maxproto", Opt_maxproto),
	133	fsparam_u32 ("minproto", Opt_minproto),
	134	fsparam_flag ("offset", Opt_offset),
	135	fsparam_u32 ("pgrp", Opt_pgrp),
	136	fsparam_flag ("strictexpire", Opt_strictexpire),
	137	fsparam_u32 ("uid", Opt_uid),
	138	{}
ebc921ca IK	139	};
ebc921ca IK	140
e6ec453b IK	141	struct autofs_fs_context {
	142	kuid_t uid;
	143	kgid_t gid;
	144	int pgrp;
	145	bool pgrp_set;
	146	};
	147
	148	/*
	149	* Open the fd. We do it here rather than in get_tree so that it's done in the
	150	* context of the system call that passed the data and not the one that
	151	* triggered the superblock creation, lest the fd gets reassigned.
	152	*/
	153	static int autofs_parse_fd(struct fs_context fc, struct autofs_sb_info sbi,
	154	struct fs_parameter *param,
	155	struct fs_parse_result *result)
546694b8 IK	156	{
	157	struct file *pipe;
	158	int ret;
	159
e6ec453b IK	160	if (param->type == fs_value_is_file) {
	161	/* came through the new api */
	162	pipe = param->file;
	163	param->file = NULL;
	164	} else {
	165	pipe = fget(result->uint_32);
	166	}
546694b8	167	if (!pipe) {
e6ec453b	168	errorf(fc, "could not open pipe file descriptor");
546694b8 IK	169	return -EBADF;
	170	}
	171
	172	ret = autofs_check_pipe(pipe);
	173	if (ret < 0) {
e6ec453b IK	174	errorf(fc, "Invalid/unusable pipe");
	175	if (param->type != fs_value_is_file)
	176	fput(pipe);
546694b8 IK	177	return -EBADF;
	178	}
	179
	180	if (sbi->pipe)
	181	fput(sbi->pipe);
	182
e6ec453b	183	sbi->pipefd = result->uint_32;
546694b8 IK	184	sbi->pipe = pipe;
	185
	186	return 0;
	187	}
	188
e6ec453b	189	static int autofs_parse_param(struct fs_context fc, struct fs_parameter param)
ebc921ca	190	{
e6ec453b IK	191	struct autofs_fs_context *ctx = fc->fs_private;
	192	struct autofs_sb_info *sbi = fc->s_fs_info;
	193	struct fs_parse_result result;
9bf964c9 IK	194	kuid_t uid;
9bf964c9 IK	195	kgid_t gid;
e6ec453b IK	196	int opt;
	197
	198	opt = fs_parse(fc, autofs_param_specs, param, &result);
	199	if (opt < 0)
	200	return opt;
ebc921ca	201
e6ec453b	202	switch (opt) {
9b273166	203	case Opt_fd:
e6ec453b	204	return autofs_parse_fd(fc, sbi, param, &result);
9b273166	205	case Opt_uid:
e6ec453b	206	uid = make_kuid(current_user_ns(), result.uint_32);
9b273166	207	if (!uid_valid(uid))
e6ec453b IK	208	return invalfc(fc, "Invalid uid");
e6ec453b IK	209	ctx->uid = uid;
9b273166 IK	210	break;
9b273166 IK	211	case Opt_gid:
e6ec453b	212	gid = make_kgid(current_user_ns(), result.uint_32);
9b273166	213	if (!gid_valid(gid))
e6ec453b IK	214	return invalfc(fc, "Invalid gid");
e6ec453b IK	215	ctx->gid = gid;
9b273166 IK	216	break;
9b273166 IK	217	case Opt_pgrp:
e6ec453b IK	218	ctx->pgrp = result.uint_32;
e6ec453b IK	219	ctx->pgrp_set = true;
9b273166 IK	220	break;
9b273166 IK	221	case Opt_minproto:
e6ec453b	222	sbi->min_proto = result.uint_32;
9b273166 IK	223	break;
9b273166 IK	224	case Opt_maxproto:
e6ec453b	225	sbi->max_proto = result.uint_32;
9b273166 IK	226	break;
	227	case Opt_indirect:
	228	set_autofs_type_indirect(&sbi->type);
	229	break;
	230	case Opt_direct:
	231	set_autofs_type_direct(&sbi->type);
	232	break;
	233	case Opt_offset:
	234	set_autofs_type_offset(&sbi->type);
	235	break;
	236	case Opt_strictexpire:
	237	sbi->flags \|= AUTOFS_SBI_STRICTEXPIRE;
	238	break;
	239	case Opt_ignore:
	240	sbi->flags \|= AUTOFS_SBI_IGNORE;
	241	}
	242
	243	return 0;
	244	}
	245
a7467430	246	static struct autofs_sb_info *autofs_alloc_sbi(void)
ebc921ca	247	{
ebc921ca	248	struct autofs_sb_info *sbi;
ebc921ca IK	249
	250	sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
	251	if (!sbi)
a7467430	252	return NULL;
ebc921ca	253
ebc921ca	254	sbi->magic = AUTOFS_SBI_MAGIC;
9d8719a4	255	sbi->flags = AUTOFS_SBI_CATATONIC;
a7467430 IK	256	sbi->min_proto = AUTOFS_MIN_PROTO_VERSION;
	257	sbi->max_proto = AUTOFS_MAX_PROTO_VERSION;
	258	sbi->pipefd = -1;
	259
ebc921ca	260	set_autofs_type_indirect(&sbi->type);
ebc921ca IK	261	mutex_init(&sbi->wq_mutex);
	262	mutex_init(&sbi->pipe_mutex);
	263	spin_lock_init(&sbi->fs_lock);
ebc921ca IK	264	spin_lock_init(&sbi->lookup_lock);
	265	INIT_LIST_HEAD(&sbi->active_list);
	266	INIT_LIST_HEAD(&sbi->expiring_list);
a7467430 IK	267
	268	return sbi;
	269	}
	270
e6ec453b	271	static int autofs_validate_protocol(struct fs_context *fc)
1f50012d	272	{
e6ec453b IK	273	struct autofs_sb_info *sbi = fc->s_fs_info;
e6ec453b IK	274
1f50012d IK	275	/* Test versions first */
	276	if (sbi->max_proto < AUTOFS_MIN_PROTO_VERSION \|\|
	277	sbi->min_proto > AUTOFS_MAX_PROTO_VERSION) {
e6ec453b	278	errorf(fc, "kernel does not match daemon version "
1f50012d IK	279	"daemon (%d, %d) kernel (%d, %d)\n",
	280	sbi->min_proto, sbi->max_proto,
	281	AUTOFS_MIN_PROTO_VERSION, AUTOFS_MAX_PROTO_VERSION);
	282	return -EINVAL;
	283	}
	284
	285	/* Establish highest kernel protocol version */
	286	if (sbi->max_proto > AUTOFS_MAX_PROTO_VERSION)
	287	sbi->version = AUTOFS_MAX_PROTO_VERSION;
	288	else
	289	sbi->version = sbi->max_proto;
dede3671 IK	290
	291	switch (sbi->version) {
	292	case 4:
	293	sbi->sub_version = 7;
	294	break;
	295	case 5:
	296	sbi->sub_version = AUTOFS_PROTO_SUBVERSION;
	297	break;
	298	default:
	299	sbi->sub_version = 0;
	300	}
1f50012d IK	301
	302	return 0;
	303	}
	304
e6ec453b	305	static int autofs_fill_super(struct super_block s, struct fs_context fc)
a7467430	306	{
e6ec453b IK	307	struct autofs_fs_context *ctx = fc->fs_private;
e6ec453b IK	308	struct autofs_sb_info *sbi = s->s_fs_info;
a7467430 IK	309	struct inode *root_inode;
a7467430 IK	310	struct dentry *root;
a7467430	311	struct autofs_info *ino;
e6ec453b	312	int ret = -ENOMEM;
a7467430 IK	313
	314	pr_debug("starting up, sbi = %p\n", sbi);
	315
	316	sbi->sb = s;
ebc921ca IK	317	s->s_blocksize = 1024;
	318	s->s_blocksize_bits = 10;
	319	s->s_magic = AUTOFS_SUPER_MAGIC;
	320	s->s_op = &autofs_sops;
	321	s->s_d_op = &autofs_dentry_operations;
	322	s->s_time_gran = 1;
	323
	324	/*
	325	* Get the root inode and dentry, but defer checking for errors.
	326	*/
	327	ino = autofs_new_ino(sbi);
e6ec453b IK	328	if (!ino)
	329	goto fail;
	330
ebc921ca	331	root_inode = autofs_get_inode(s, S_IFDIR \| 0755);
e6ec453b IK	332	root_inode->i_uid = ctx->uid;
	333	root_inode->i_gid = ctx->gid;
	334
ebc921ca	335	root = d_make_root(root_inode);
e6ec453b	336	if (!root)
ebc921ca	337	goto fail_ino;
ebc921ca IK	338
	339	root->d_fsdata = ino;
	340
e6ec453b IK	341	if (ctx->pgrp_set) {
e6ec453b IK	342	sbi->oz_pgrp = find_get_pid(ctx->pgrp);
ebc921ca	343	if (!sbi->oz_pgrp) {
e6ec453b IK	344	ret = invalf(fc, "Could not find process group %d",
e6ec453b IK	345	ctx->pgrp);
ebc921ca IK	346	goto fail_dput;
	347	}
	348	} else {
	349	sbi->oz_pgrp = get_task_pid(current, PIDTYPE_PGID);
	350	}
	351
	352	if (autofs_type_trigger(sbi->type))
	353	__managed_dentry_set_managed(root);
	354
	355	root_inode->i_fop = &autofs_root_operations;
	356	root_inode->i_op = &autofs_dir_inode_operations;
	357
9bf964c9 IK	358	pr_debug("pipe fd = %d, pgrp = %u\n",
9bf964c9 IK	359	sbi->pipefd, pid_nr(sbi->oz_pgrp));
ebc921ca	360
9d8719a4	361	sbi->flags &= ~AUTOFS_SBI_CATATONIC;
ebc921ca IK	362
	363	/*
	364	* Success! Install the root dentry now to indicate completion.
	365	*/
	366	s->s_root = root;
	367	return 0;
	368
	369	/*
	370	* Failure ... clean up.
	371	*/
ebc921ca IK	372	fail_dput:
ebc921ca IK	373	dput(root);
e6ec453b	374	goto fail;
ebc921ca IK	375	fail_ino:
ebc921ca IK	376	autofs_free_ino(ino);
e6ec453b	377	fail:
ebc921ca IK	378	return ret;
	379	}
	380
e6ec453b IK	381	/*
	382	* Validate the parameters and then request a superblock.
	383	*/
	384	static int autofs_get_tree(struct fs_context *fc)
	385	{
	386	struct autofs_sb_info *sbi = fc->s_fs_info;
	387	int ret;
	388
	389	ret = autofs_validate_protocol(fc);
	390	if (ret)
	391	return ret;
	392
	393	if (sbi->pipefd < 0)
	394	return invalf(fc, "No control pipe specified");
	395
	396	return get_tree_nodev(fc, autofs_fill_super);
	397	}
	398
	399	static void autofs_free_fc(struct fs_context *fc)
	400	{
	401	struct autofs_fs_context *ctx = fc->fs_private;
	402	struct autofs_sb_info *sbi = fc->s_fs_info;
	403
	404	if (sbi) {
	405	if (sbi->pipe)
	406	fput(sbi->pipe);
	407	kfree(sbi);
	408	}
	409	kfree(ctx);
	410	}
	411
	412	static const struct fs_context_operations autofs_context_ops = {
	413	.free = autofs_free_fc,
	414	.parse_param = autofs_parse_param,
	415	.get_tree = autofs_get_tree,
	416	};
	417
	418	/*
	419	* Set up the filesystem mount context.
	420	*/
	421	int autofs_init_fs_context(struct fs_context *fc)
	422	{
	423	struct autofs_fs_context *ctx;
	424	struct autofs_sb_info *sbi;
	425
	426	ctx = kzalloc(sizeof(struct autofs_fs_context), GFP_KERNEL);
	427	if (!ctx)
	428	goto nomem;
	429
	430	ctx->uid = current_uid();
	431	ctx->gid = current_gid();
	432
	433	sbi = autofs_alloc_sbi();
	434	if (!sbi)
	435	goto nomem_ctx;
	436
	437	fc->fs_private = ctx;
	438	fc->s_fs_info = sbi;
	439	fc->ops = &autofs_context_ops;
	440	return 0;
	441
	442	nomem_ctx:
	443	kfree(ctx);
	444	nomem:
445	return -ENOMEM;
446	}
447
ebc921ca IK	448	struct inode autofs_get_inode(struct super_block sb, umode_t mode)
	449	{
	450	struct inode *inode = new_inode(sb);
	451
	452	if (inode == NULL)
	453	return NULL;
	454
	455	inode->i_mode = mode;
	456	if (sb->s_root) {
	457	inode->i_uid = d_inode(sb->s_root)->i_uid;
	458	inode->i_gid = d_inode(sb->s_root)->i_gid;
	459	}
36aa5eae	460	inode->i_atime = inode->i_mtime = inode_set_ctime_current(inode);
ebc921ca IK	461	inode->i_ino = get_next_ino();
	462
	463	if (S_ISDIR(mode)) {
	464	set_nlink(inode, 2);
	465	inode->i_op = &autofs_dir_inode_operations;
	466	inode->i_fop = &autofs_dir_operations;
	467	} else if (S_ISLNK(mode)) {
	468	inode->i_op = &autofs_symlink_inode_operations;
	469	} else
	470	WARN_ON(1);
	471
	472	return inode;
	473	}