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

/* -*- linux-c -*- --------------------------------------------------------- *
 *
 * linux/fs/autofs/inode.c
 *
 *  Copyright 1997-1998 Transmeta Corporation -- All Rights Reserved
 *
 * 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/mm.h>
#include <linux/slab.h>
#include <linux/file.h>
#include <linux/parser.h>
#include <linux/bitops.h>
#include <linux/magic.h>
#include "autofs_i.h"
#include <linux/module.h>

void autofs_kill_sb(struct super_block *sb)
{
	struct autofs_sb_info *sbi = autofs_sbi(sb);
	unsigned int n;

	/*
	 * In the event of a failure in get_sb_nodev the superblock
	 * info is not present so nothing else has been setup, so
	 * just exit when we are called from deactivate_super.
	 */
	if (!sbi)
		return;

	if ( !sbi->catatonic )
		autofs_catatonic_mode(sbi); /* Free wait queues, close pipe */

	autofs_hash_nuke(sbi);
	for ( n = 0 ; n < AUTOFS_MAX_SYMLINKS ; n++ ) {
		if ( test_bit(n, sbi->symlink_bitmap) )
			kfree(sbi->symlink[n].data);
	}

	kfree(sb->s_fs_info);

	DPRINTK(("autofs: shutting down\n"));
	kill_anon_super(sb);
}

static void autofs_read_inode(struct inode *inode);

static struct super_operations autofs_sops = {
	.read_inode	= autofs_read_inode,
	.statfs		= simple_statfs,
};

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

static match_table_t autofs_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_err, NULL}
};

static int parse_options(char *options, int *pipefd, uid_t *uid, gid_t *gid, pid_t *pgrp, int *minproto, int *maxproto)
{
	char *p;
	substring_t args[MAX_OPT_ARGS];
	int option;

	*uid = current->uid;
	*gid = current->gid;
	*pgrp = process_group(current);

	*minproto = *maxproto = AUTOFS_PROTO_VERSION;

	*pipefd = -1;

	if (!options)
		return 1;

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

		token = match_token(p, autofs_tokens, args);
		switch (token) {
		case Opt_fd:
			if (match_int(&args[0], &option))
				return 1;
			*pipefd = option;
			break;
		case Opt_uid:
			if (match_int(&args[0], &option))
				return 1;
			*uid = option;
			break;
		case Opt_gid:
			if (match_int(&args[0], &option))
				return 1;
			*gid = option;
			break;
		case Opt_pgrp:
			if (match_int(&args[0], &option))
				return 1;
			*pgrp = option;
			break;
		case Opt_minproto:
			if (match_int(&args[0], &option))
				return 1;
			*minproto = option;
			break;
		case Opt_maxproto:
			if (match_int(&args[0], &option))
				return 1;
			*maxproto = option;
			break;
		default:
			return 1;
		}
	}
	return (*pipefd < 0);
}

int autofs_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;
	int minproto, maxproto;

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

	s->s_fs_info = sbi;
	sbi->magic = AUTOFS_SBI_MAGIC;
	sbi->pipe = NULL;
	sbi->catatonic = 1;
	sbi->exp_timeout = 0;
	sbi->oz_pgrp = process_group(current);
	autofs_initialize_hash(&sbi->dirhash);
	sbi->queues = NULL;
	memset(sbi->symlink_bitmap, 0, sizeof(long)*AUTOFS_SYMLINK_BITMAP_LEN);
	sbi->next_dir_ino = AUTOFS_FIRST_DIR_INO;
	s->s_blocksize = 1024;
	s->s_blocksize_bits = 10;
	s->s_magic = AUTOFS_SUPER_MAGIC;
	s->s_op = &autofs_sops;
	s->s_time_gran = 1;
	sbi->sb = s;

	root_inode = iget(s, AUTOFS_ROOT_INO);
	root = d_alloc_root(root_inode);
	pipe = NULL;

	if (!root)
		goto fail_iput;

	/* Can this call block?  - WTF cares? s is locked. */
	if ( parse_options(data,&pipefd,&root_inode->i_uid,&root_inode->i_gid,&sbi->oz_pgrp,&minproto,&maxproto) ) {
		printk("autofs: called with bogus options\n");
		goto fail_dput;
	}

	/* Couldn't this be tested earlier? */
	if ( minproto > AUTOFS_PROTO_VERSION || 
	     maxproto < AUTOFS_PROTO_VERSION ) {
		printk("autofs: kernel does not match daemon version\n");
		goto fail_dput;
	}

	DPRINTK(("autofs: pipe fd = %d, pgrp = %u\n", 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->catatonic = 0;

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

fail_fput:
	printk("autofs: pipe file descriptor does not contain proper ops\n");
	fput(pipe);
fail_dput:
	dput(root);
	goto fail_free;
fail_iput:
	printk("autofs: get root dentry failed\n");
	iput(root_inode);
fail_free:
	kfree(sbi);
	s->s_fs_info = NULL;
	kill_anon_super(s);
fail_unlock:
	return -EINVAL;
}

static void autofs_read_inode(struct inode *inode)
{
	ino_t ino = inode->i_ino;
	unsigned int n;
	struct autofs_sb_info *sbi = autofs_sbi(inode->i_sb);

	/* Initialize to the default case (stub directory) */

	inode->i_op = &simple_dir_inode_operations;
	inode->i_fop = &simple_dir_operations;
	inode->i_mode = S_IFDIR | S_IRUGO | S_IXUGO;
	inode->i_nlink = 2;
	inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
	inode->i_blocks = 0;

	if ( ino == AUTOFS_ROOT_INO ) {
		inode->i_mode = S_IFDIR | S_IRUGO | S_IXUGO | S_IWUSR;
		inode->i_op = &autofs_root_inode_operations;
		inode->i_fop = &autofs_root_operations;
		inode->i_uid = inode->i_gid = 0; /* Changed in read_super */
		return;
	} 
	
	inode->i_uid = inode->i_sb->s_root->d_inode->i_uid;
	inode->i_gid = inode->i_sb->s_root->d_inode->i_gid;
	
	if ( ino >= AUTOFS_FIRST_SYMLINK && ino < AUTOFS_FIRST_DIR_INO ) {
		/* Symlink inode - should be in symlink list */
		struct autofs_symlink *sl;

		n = ino - AUTOFS_FIRST_SYMLINK;
		if ( n >= AUTOFS_MAX_SYMLINKS || !test_bit(n,sbi->symlink_bitmap)) {
			printk("autofs: Looking for bad symlink inode %u\n", (unsigned int) ino);
			return;
		}
		
		inode->i_op = &autofs_symlink_inode_operations;
		sl = &sbi->symlink[n];
		inode->i_private = sl;
		inode->i_mode = S_IFLNK | S_IRWXUGO;
		inode->i_mtime.tv_sec = inode->i_ctime.tv_sec = sl->mtime;
		inode->i_mtime.tv_nsec = inode->i_ctime.tv_nsec = 0;
		inode->i_size = sl->len;
		inode->i_nlink = 1;
	}
}
Commit	Line	Data
1da177e4 LT	1	/* -- linux-c -- --------------------------------------------------------- *
	2	*
	3	* linux/fs/autofs/inode.c
	4	*
	5	* Copyright 1997-1998 Transmeta Corporation -- All Rights Reserved
	6	*
	7	* This file is part of the Linux kernel and is made available under
	8	* the terms of the GNU General Public License, version 2, or at your
	9	* option, any later version, incorporated herein by reference.
	10	*
	11	* ------------------------------------------------------------------------- */
	12
	13	#include <linux/kernel.h>
	14	#include <linux/mm.h>
	15	#include <linux/slab.h>
	16	#include <linux/file.h>
	17	#include <linux/parser.h>
	18	#include <linux/bitops.h>
e18fa700	19	#include <linux/magic.h>
1da177e4 LT	20	#include "autofs_i.h"
	21	#include <linux/module.h>
	22
0e7d7382	23	void autofs_kill_sb(struct super_block *sb)
1da177e4 LT	24	{
	25	struct autofs_sb_info *sbi = autofs_sbi(sb);
	26	unsigned int n;
	27
ba8df43c IK	28	/*
	29	* In the event of a failure in get_sb_nodev the superblock
	30	* info is not present so nothing else has been setup, so
	31	* just exit when we are called from deactivate_super.
	32	*/
	33	if (!sbi)
	34	return;
	35
1da177e4 LT	36	if ( !sbi->catatonic )
	37	autofs_catatonic_mode(sbi); /* Free wait queues, close pipe */
	38
f76baf93	39	autofs_hash_nuke(sbi);
1da177e4 LT	40	for ( n = 0 ; n < AUTOFS_MAX_SYMLINKS ; n++ ) {
	41	if ( test_bit(n, sbi->symlink_bitmap) )
	42	kfree(sbi->symlink[n].data);
	43	}
	44
	45	kfree(sb->s_fs_info);
	46
	47	DPRINTK(("autofs: shutting down\n"));
0e7d7382	48	kill_anon_super(sb);
1da177e4 LT	49	}
	50
	51	static void autofs_read_inode(struct inode *inode);
	52
	53	static struct super_operations autofs_sops = {
	54	.read_inode = autofs_read_inode,
1da177e4 LT	55	.statfs = simple_statfs,
	56	};
	57
	58	enum {Opt_err, Opt_fd, Opt_uid, Opt_gid, Opt_pgrp, Opt_minproto, Opt_maxproto};
	59
	60	static match_table_t autofs_tokens = {
	61	{Opt_fd, "fd=%u"},
	62	{Opt_uid, "uid=%u"},
	63	{Opt_gid, "gid=%u"},
	64	{Opt_pgrp, "pgrp=%u"},
	65	{Opt_minproto, "minproto=%u"},
	66	{Opt_maxproto, "maxproto=%u"},
	67	{Opt_err, NULL}
	68	};
	69
	70	static int parse_options(char options, int pipefd, uid_t uid, gid_t gid, pid_t pgrp, int minproto, int *maxproto)
	71	{
	72	char *p;
	73	substring_t args[MAX_OPT_ARGS];
	74	int option;
	75
	76	*uid = current->uid;
	77	*gid = current->gid;
	78	*pgrp = process_group(current);
	79
	80	minproto = maxproto = AUTOFS_PROTO_VERSION;
	81
	82	*pipefd = -1;
	83
	84	if (!options)
	85	return 1;
	86
	87	while ((p = strsep(&options, ",")) != NULL) {
	88	int token;
	89	if (!*p)
	90	continue;
	91
	92	token = match_token(p, autofs_tokens, args);
	93	switch (token) {
	94	case Opt_fd:
	95	if (match_int(&args[0], &option))
	96	return 1;
	97	*pipefd = option;
	98	break;
	99	case Opt_uid:
	100	if (match_int(&args[0], &option))
	101	return 1;
	102	*uid = option;
	103	break;
	104	case Opt_gid:
	105	if (match_int(&args[0], &option))
	106	return 1;
	107	*gid = option;
	108	break;
	109	case Opt_pgrp:
	110	if (match_int(&args[0], &option))
	111	return 1;
	112	*pgrp = option;
	113	break;
	114	case Opt_minproto:
	115	if (match_int(&args[0], &option))
	116	return 1;
	117	*minproto = option;
	118	break;
119	case Opt_maxproto:
120	if (match_int(&args[0], &option))
121	return 1;
122	*maxproto = option;
123	break;
124	default:
125	return 1;
126	}
127	}
128	return (*pipefd < 0);
129	}
130
131	int autofs_fill_super(struct super_block s, void data, int silent)
132	{
133	struct inode * root_inode;
134	struct dentry * root;
135	struct file * pipe;
136	int pipefd;
137	struct autofs_sb_info *sbi;
138	int minproto, maxproto;
139
f8314dc6	140	sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
1da177e4 LT	141	if ( !sbi )
1da177e4 LT	142	goto fail_unlock;
1da177e4 LT	143	DPRINTK(("autofs: starting up, sbi = %p\n",sbi));
	144
	145	s->s_fs_info = sbi;
	146	sbi->magic = AUTOFS_SBI_MAGIC;
ba8df43c IK	147	sbi->pipe = NULL;
ba8df43c IK	148	sbi->catatonic = 1;
1da177e4 LT	149	sbi->exp_timeout = 0;
	150	sbi->oz_pgrp = process_group(current);
	151	autofs_initialize_hash(&sbi->dirhash);
	152	sbi->queues = NULL;
	153	memset(sbi->symlink_bitmap, 0, sizeof(long)*AUTOFS_SYMLINK_BITMAP_LEN);
	154	sbi->next_dir_ino = AUTOFS_FIRST_DIR_INO;
	155	s->s_blocksize = 1024;
	156	s->s_blocksize_bits = 10;
	157	s->s_magic = AUTOFS_SUPER_MAGIC;
	158	s->s_op = &autofs_sops;
	159	s->s_time_gran = 1;
f76baf93	160	sbi->sb = s;
1da177e4 LT	161
	162	root_inode = iget(s, AUTOFS_ROOT_INO);
	163	root = d_alloc_root(root_inode);
	164	pipe = NULL;
	165
	166	if (!root)
	167	goto fail_iput;
	168
	169	/* Can this call block? - WTF cares? s is locked. */
	170	if ( parse_options(data,&pipefd,&root_inode->i_uid,&root_inode->i_gid,&sbi->oz_pgrp,&minproto,&maxproto) ) {
	171	printk("autofs: called with bogus options\n");
	172	goto fail_dput;
	173	}
	174
	175	/* Couldn't this be tested earlier? */
	176	if ( minproto > AUTOFS_PROTO_VERSION \|\|
	177	maxproto < AUTOFS_PROTO_VERSION ) {
	178	printk("autofs: kernel does not match daemon version\n");
	179	goto fail_dput;
	180	}
	181
	182	DPRINTK(("autofs: pipe fd = %d, pgrp = %u\n", pipefd, sbi->oz_pgrp));
	183	pipe = fget(pipefd);
	184
	185	if ( !pipe ) {
	186	printk("autofs: could not open pipe file descriptor\n");
	187	goto fail_dput;
	188	}
	189	if ( !pipe->f_op \|\| !pipe->f_op->write )
	190	goto fail_fput;
	191	sbi->pipe = pipe;
ba8df43c	192	sbi->catatonic = 0;
1da177e4 LT	193
	194	/*
	195	* Success! Install the root dentry now to indicate completion.
	196	*/
	197	s->s_root = root;
	198	return 0;
	199
	200	fail_fput:
	201	printk("autofs: pipe file descriptor does not contain proper ops\n");
	202	fput(pipe);
	203	fail_dput:
	204	dput(root);
	205	goto fail_free;
	206	fail_iput:
	207	printk("autofs: get root dentry failed\n");
	208	iput(root_inode);
	209	fail_free:
	210	kfree(sbi);
ba8df43c IK	211	s->s_fs_info = NULL;
ba8df43c IK	212	kill_anon_super(s);
1da177e4 LT	213	fail_unlock:
	214	return -EINVAL;
	215	}
	216
	217	static void autofs_read_inode(struct inode *inode)
	218	{
	219	ino_t ino = inode->i_ino;
	220	unsigned int n;
	221	struct autofs_sb_info *sbi = autofs_sbi(inode->i_sb);
	222
	223	/* Initialize to the default case (stub directory) */
	224
	225	inode->i_op = &simple_dir_inode_operations;
	226	inode->i_fop = &simple_dir_operations;
	227	inode->i_mode = S_IFDIR \| S_IRUGO \| S_IXUGO;
	228	inode->i_nlink = 2;
	229	inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
	230	inode->i_blocks = 0;
1da177e4 LT	231
	232	if ( ino == AUTOFS_ROOT_INO ) {
	233	inode->i_mode = S_IFDIR \| S_IRUGO \| S_IXUGO \| S_IWUSR;
	234	inode->i_op = &autofs_root_inode_operations;
	235	inode->i_fop = &autofs_root_operations;
	236	inode->i_uid = inode->i_gid = 0; /* Changed in read_super */
	237	return;
	238	}
	239
	240	inode->i_uid = inode->i_sb->s_root->d_inode->i_uid;
	241	inode->i_gid = inode->i_sb->s_root->d_inode->i_gid;
	242
	243	if ( ino >= AUTOFS_FIRST_SYMLINK && ino < AUTOFS_FIRST_DIR_INO ) {
	244	/* Symlink inode - should be in symlink list */
	245	struct autofs_symlink *sl;
	246
	247	n = ino - AUTOFS_FIRST_SYMLINK;
	248	if ( n >= AUTOFS_MAX_SYMLINKS \|\| !test_bit(n,sbi->symlink_bitmap)) {
	249	printk("autofs: Looking for bad symlink inode %u\n", (unsigned int) ino);
	250	return;
	251	}
	252
	253	inode->i_op = &autofs_symlink_inode_operations;
	254	sl = &sbi->symlink[n];
8e18e294	255	inode->i_private = sl;
1da177e4 LT	256	inode->i_mode = S_IFLNK \| S_IRWXUGO;
	257	inode->i_mtime.tv_sec = inode->i_ctime.tv_sec = sl->mtime;
	258	inode->i_mtime.tv_nsec = inode->i_ctime.tv_nsec = 0;
	259	inode->i_size = sl->len;
	260	inode->i_nlink = 1;
	261	}
	262	}