[linux.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 call kill_anon_super when we are called from
	 * deactivate_super.
	 */
	if (!sbi)
		goto out_kill_sb;

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

	put_pid(sbi->oz_pgrp);

	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);

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

static const struct super_operations autofs_sops = {
	.statfs		= simple_statfs,
	.show_options	= generic_show_options,
};

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

static const 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 = task_pgrp_nr(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;
	pid_t pgid;

	save_mount_options(s, data);

	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;
	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 = autofs_iget(s, AUTOFS_ROOT_INO);
	if (IS_ERR(root_inode))
		goto fail_free;
	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, &pgid, &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, pgid));
	sbi->oz_pgrp = find_get_pid(pgid);

	if (!sbi->oz_pgrp) {
		printk("autofs: could not find process group %d\n", pgid);
		goto fail_dput;
	}

	pipe = fget(pipefd);
	
	if (!pipe) {
		printk("autofs: could not open pipe file descriptor\n");
		goto fail_put_pid;
	}

	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_put_pid:
	put_pid(sbi->oz_pgrp);
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;
fail_unlock:
	return -EINVAL;
}

struct inode *autofs_iget(struct super_block *sb, unsigned long ino)
{
	unsigned int n;
	struct autofs_sb_info *sbi = autofs_sbi(sb);
	struct inode *inode;

	inode = iget_locked(sb, ino);
	if (!inode)
		return ERR_PTR(-ENOMEM);
	if (!(inode->i_state & I_NEW))
		return inode;

	/* 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;

	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;
		goto done;
	} 
	
	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);
			goto done;
		}
		
		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;
	}

done:
	unlock_new_inode(inode);
	return inode;
}
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
c949d4eb JK	31	* just call kill_anon_super when we are called from
c949d4eb JK	32	* deactivate_super.
ba8df43c IK	33	*/
ba8df43c IK	34	if (!sbi)
c949d4eb	35	goto out_kill_sb;
ba8df43c	36
d78e53c8	37	if (!sbi->catatonic)
1da177e4 LT	38	autofs_catatonic_mode(sbi); /* Free wait queues, close pipe */
1da177e4 LT	39
fa0334f1 SB	40	put_pid(sbi->oz_pgrp);
fa0334f1 SB	41
f76baf93	42	autofs_hash_nuke(sbi);
d78e53c8 SB	43	for (n = 0; n < AUTOFS_MAX_SYMLINKS; n++) {
d78e53c8 SB	44	if (test_bit(n, sbi->symlink_bitmap))
1da177e4 LT	45	kfree(sbi->symlink[n].data);
	46	}
	47
	48	kfree(sb->s_fs_info);
	49
c949d4eb	50	out_kill_sb:
1da177e4	51	DPRINTK(("autofs: shutting down\n"));
0e7d7382	52	kill_anon_super(sb);
1da177e4 LT	53	}
1da177e4 LT	54
ee9b6d61	55	static const struct super_operations autofs_sops = {
1da177e4	56	.statfs = simple_statfs,
979db754	57	.show_options = generic_show_options,
1da177e4 LT	58	};
	59
	60	enum {Opt_err, Opt_fd, Opt_uid, Opt_gid, Opt_pgrp, Opt_minproto, Opt_maxproto};
	61
a447c093	62	static const match_table_t autofs_tokens = {
1da177e4 LT	63	{Opt_fd, "fd=%u"},
	64	{Opt_uid, "uid=%u"},
	65	{Opt_gid, "gid=%u"},
	66	{Opt_pgrp, "pgrp=%u"},
	67	{Opt_minproto, "minproto=%u"},
	68	{Opt_maxproto, "maxproto=%u"},
	69	{Opt_err, NULL}
	70	};
	71
d78e53c8 SB	72	static int parse_options(char options, int pipefd, uid_t uid, gid_t gid,
d78e53c8 SB	73	pid_t pgrp, int minproto, int *maxproto)
1da177e4 LT	74	{
	75	char *p;
	76	substring_t args[MAX_OPT_ARGS];
	77	int option;
	78
73c646e4 DH	79	*uid = current_uid();
73c646e4 DH	80	*gid = current_gid();
a47afb0f	81	*pgrp = task_pgrp_nr(current);
1da177e4 LT	82
	83	minproto = maxproto = AUTOFS_PROTO_VERSION;
	84
	85	*pipefd = -1;
	86
	87	if (!options)
	88	return 1;
	89
	90	while ((p = strsep(&options, ",")) != NULL) {
	91	int token;
	92	if (!*p)
	93	continue;
	94
	95	token = match_token(p, autofs_tokens, args);
	96	switch (token) {
	97	case Opt_fd:
	98	if (match_int(&args[0], &option))
	99	return 1;
	100	*pipefd = option;
	101	break;
	102	case Opt_uid:
	103	if (match_int(&args[0], &option))
	104	return 1;
	105	*uid = option;
	106	break;
	107	case Opt_gid:
	108	if (match_int(&args[0], &option))
	109	return 1;
	110	*gid = option;
	111	break;
	112	case Opt_pgrp:
	113	if (match_int(&args[0], &option))
	114	return 1;
	115	*pgrp = option;
	116	break;
	117	case Opt_minproto:
	118	if (match_int(&args[0], &option))
	119	return 1;
	120	*minproto = option;
	121	break;
	122	case Opt_maxproto:
	123	if (match_int(&args[0], &option))
	124	return 1;
	125	*maxproto = option;
	126	break;
	127	default:
	128	return 1;
	129	}
	130	}
	131	return (*pipefd < 0);
	132	}
	133
	134	int autofs_fill_super(struct super_block s, void data, int silent)
	135	{
	136	struct inode * root_inode;
	137	struct dentry * root;
	138	struct file * pipe;
	139	int pipefd;
	140	struct autofs_sb_info *sbi;
	141	int minproto, maxproto;
fa0334f1	142	pid_t pgid;
1da177e4	143
979db754 MS	144	save_mount_options(s, data);
979db754 MS	145
f8314dc6	146	sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
d78e53c8	147	if (!sbi)
1da177e4	148	goto fail_unlock;
1da177e4 LT	149	DPRINTK(("autofs: starting up, sbi = %p\n",sbi));
	150
	151	s->s_fs_info = sbi;
	152	sbi->magic = AUTOFS_SBI_MAGIC;
ba8df43c IK	153	sbi->pipe = NULL;
ba8df43c IK	154	sbi->catatonic = 1;
1da177e4	155	sbi->exp_timeout = 0;
1da177e4 LT	156	autofs_initialize_hash(&sbi->dirhash);
	157	sbi->queues = NULL;
	158	memset(sbi->symlink_bitmap, 0, sizeof(long)*AUTOFS_SYMLINK_BITMAP_LEN);
	159	sbi->next_dir_ino = AUTOFS_FIRST_DIR_INO;
	160	s->s_blocksize = 1024;
	161	s->s_blocksize_bits = 10;
	162	s->s_magic = AUTOFS_SUPER_MAGIC;
	163	s->s_op = &autofs_sops;
	164	s->s_time_gran = 1;
f76baf93	165	sbi->sb = s;
1da177e4	166
62328a02 DH	167	root_inode = autofs_iget(s, AUTOFS_ROOT_INO);
	168	if (IS_ERR(root_inode))
	169	goto fail_free;
1da177e4 LT	170	root = d_alloc_root(root_inode);
	171	pipe = NULL;
	172
	173	if (!root)
	174	goto fail_iput;
	175
	176	/* Can this call block? - WTF cares? s is locked. */
d78e53c8	177	if (parse_options(data, &pipefd, &root_inode->i_uid,
fa0334f1	178	&root_inode->i_gid, &pgid, &minproto,
d78e53c8	179	&maxproto)) {
1da177e4 LT	180	printk("autofs: called with bogus options\n");
	181	goto fail_dput;
	182	}
	183
	184	/* Couldn't this be tested earlier? */
d78e53c8 SB	185	if (minproto > AUTOFS_PROTO_VERSION \|\|
d78e53c8 SB	186	maxproto < AUTOFS_PROTO_VERSION) {
1da177e4 LT	187	printk("autofs: kernel does not match daemon version\n");
	188	goto fail_dput;
	189	}
	190
fa0334f1 SB	191	DPRINTK(("autofs: pipe fd = %d, pgrp = %u\n", pipefd, pgid));
	192	sbi->oz_pgrp = find_get_pid(pgid);
	193
	194	if (!sbi->oz_pgrp) {
	195	printk("autofs: could not find process group %d\n", pgid);
	196	goto fail_dput;
	197	}
	198
1da177e4 LT	199	pipe = fget(pipefd);
1da177e4 LT	200
d78e53c8	201	if (!pipe) {
1da177e4	202	printk("autofs: could not open pipe file descriptor\n");
fa0334f1	203	goto fail_put_pid;
1da177e4	204	}
fa0334f1	205
d78e53c8	206	if (!pipe->f_op \|\| !pipe->f_op->write)
1da177e4 LT	207	goto fail_fput;
1da177e4 LT	208	sbi->pipe = pipe;
ba8df43c	209	sbi->catatonic = 0;
1da177e4 LT	210
	211	/*
	212	* Success! Install the root dentry now to indicate completion.
	213	*/
	214	s->s_root = root;
	215	return 0;
	216
	217	fail_fput:
	218	printk("autofs: pipe file descriptor does not contain proper ops\n");
	219	fput(pipe);
fa0334f1 SB	220	fail_put_pid:
fa0334f1 SB	221	put_pid(sbi->oz_pgrp);
1da177e4 LT	222	fail_dput:
	223	dput(root);
	224	goto fail_free;
	225	fail_iput:
	226	printk("autofs: get root dentry failed\n");
	227	iput(root_inode);
	228	fail_free:
	229	kfree(sbi);
ba8df43c	230	s->s_fs_info = NULL;
1da177e4 LT	231	fail_unlock:
	232	return -EINVAL;
	233	}
	234
62328a02	235	struct inode autofs_iget(struct super_block sb, unsigned long ino)
1da177e4	236	{
1da177e4	237	unsigned int n;
62328a02 DH	238	struct autofs_sb_info *sbi = autofs_sbi(sb);
	239	struct inode *inode;
	240
	241	inode = iget_locked(sb, ino);
	242	if (!inode)
	243	return ERR_PTR(-ENOMEM);
	244	if (!(inode->i_state & I_NEW))
	245	return inode;
1da177e4 LT	246
	247	/* Initialize to the default case (stub directory) */
	248
	249	inode->i_op = &simple_dir_inode_operations;
	250	inode->i_fop = &simple_dir_operations;
	251	inode->i_mode = S_IFDIR \| S_IRUGO \| S_IXUGO;
	252	inode->i_nlink = 2;
	253	inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
1da177e4	254
d78e53c8	255	if (ino == AUTOFS_ROOT_INO) {
1da177e4 LT	256	inode->i_mode = S_IFDIR \| S_IRUGO \| S_IXUGO \| S_IWUSR;
	257	inode->i_op = &autofs_root_inode_operations;
	258	inode->i_fop = &autofs_root_operations;
62328a02	259	goto done;
1da177e4 LT	260	}
	261
	262	inode->i_uid = inode->i_sb->s_root->d_inode->i_uid;
	263	inode->i_gid = inode->i_sb->s_root->d_inode->i_gid;
	264
d78e53c8	265	if (ino >= AUTOFS_FIRST_SYMLINK && ino < AUTOFS_FIRST_DIR_INO) {
1da177e4 LT	266	/* Symlink inode - should be in symlink list */
	267	struct autofs_symlink *sl;
	268
	269	n = ino - AUTOFS_FIRST_SYMLINK;
d78e53c8	270	if (n >= AUTOFS_MAX_SYMLINKS \|\| !test_bit(n,sbi->symlink_bitmap)) {
1da177e4	271	printk("autofs: Looking for bad symlink inode %u\n", (unsigned int) ino);
62328a02	272	goto done;
1da177e4 LT	273	}
	274
	275	inode->i_op = &autofs_symlink_inode_operations;
	276	sl = &sbi->symlink[n];
8e18e294	277	inode->i_private = sl;
1da177e4 LT	278	inode->i_mode = S_IFLNK \| S_IRWXUGO;
	279	inode->i_mtime.tv_sec = inode->i_ctime.tv_sec = sl->mtime;
	280	inode->i_mtime.tv_nsec = inode->i_ctime.tv_nsec = 0;
	281	inode->i_size = sl->len;
	282	inode->i_nlink = 1;
	283	}
62328a02 DH	284
	285	done:
	286	unlock_new_inode(inode);
	287	return inode;
1da177e4	288	}