[linux.git] / fs / ufs / namei.c

/*
 * linux/fs/ufs/namei.c
 *
 * Migration to usage of "page cache" on May 2006 by
 * Evgeniy Dushistov <[email protected]> based on ext2 code base.
 *
 * Copyright (C) 1998
 * Daniel Pirkl <[email protected]>
 * Charles University, Faculty of Mathematics and Physics
 *
 *  from
 *
 *  linux/fs/ext2/namei.c
 *
 * Copyright (C) 1992, 1993, 1994, 1995
 * Remy Card ([email protected])
 * Laboratoire MASI - Institut Blaise Pascal
 * Universite Pierre et Marie Curie (Paris VI)
 *
 *  from
 *
 *  linux/fs/minix/namei.c
 *
 *  Copyright (C) 1991, 1992  Linus Torvalds
 *
 *  Big-endian to little-endian byte-swapping/bitmaps by
 *        David S. Miller ([email protected]), 1995
 */

#include <linux/time.h>
#include <linux/fs.h>
#include <linux/smp_lock.h>

#include "ufs_fs.h"
#include "ufs.h"
#include "util.h"

static inline int ufs_add_nondir(struct dentry *dentry, struct inode *inode)
{
	int err = ufs_add_link(dentry, inode);
	if (!err) {
		d_instantiate(dentry, inode);
		return 0;
	}
	inode_dec_link_count(inode);
	iput(inode);
	return err;
}

static struct dentry *ufs_lookup(struct inode * dir, struct dentry *dentry, struct nameidata *nd)
{
	struct inode * inode = NULL;
	ino_t ino;
	
	if (dentry->d_name.len > UFS_MAXNAMLEN)
		return ERR_PTR(-ENAMETOOLONG);

	lock_kernel();
	ino = ufs_inode_by_name(dir, dentry);
	if (ino) {
		inode = ufs_iget(dir->i_sb, ino);
		if (IS_ERR(inode)) {
			unlock_kernel();
			return ERR_CAST(inode);
		}
	}
	unlock_kernel();
	d_add(dentry, inode);
	return NULL;
}

/*
 * By the time this is called, we already have created
 * the directory cache entry for the new file, but it
 * is so far negative - it has no inode.
 *
 * If the create succeeds, we fill in the inode information
 * with d_instantiate(). 
 */
static int ufs_create (struct inode * dir, struct dentry * dentry, int mode,
		struct nameidata *nd)
{
	struct inode *inode;
	int err;

	UFSD("BEGIN\n");
	inode = ufs_new_inode(dir, mode);
	err = PTR_ERR(inode);

	if (!IS_ERR(inode)) {
		inode->i_op = &ufs_file_inode_operations;
		inode->i_fop = &ufs_file_operations;
		inode->i_mapping->a_ops = &ufs_aops;
		mark_inode_dirty(inode);
		lock_kernel();
		err = ufs_add_nondir(dentry, inode);
		unlock_kernel();
	}
	UFSD("END: err=%d\n", err);
	return err;
}

static int ufs_mknod (struct inode * dir, struct dentry *dentry, int mode, dev_t rdev)
{
	struct inode *inode;
	int err;

	if (!old_valid_dev(rdev))
		return -EINVAL;
	inode = ufs_new_inode(dir, mode);
	err = PTR_ERR(inode);
	if (!IS_ERR(inode)) {
		init_special_inode(inode, mode, rdev);
		ufs_set_inode_dev(inode->i_sb, UFS_I(inode), rdev);
		mark_inode_dirty(inode);
		lock_kernel();
		err = ufs_add_nondir(dentry, inode);
		unlock_kernel();
	}
	return err;
}

static int ufs_symlink (struct inode * dir, struct dentry * dentry,
	const char * symname)
{
	struct super_block * sb = dir->i_sb;
	int err = -ENAMETOOLONG;
	unsigned l = strlen(symname)+1;
	struct inode * inode;

	if (l > sb->s_blocksize)
		goto out_notlocked;

	lock_kernel();
	inode = ufs_new_inode(dir, S_IFLNK | S_IRWXUGO);
	err = PTR_ERR(inode);
	if (IS_ERR(inode))
		goto out;

	if (l > UFS_SB(sb)->s_uspi->s_maxsymlinklen) {
		/* slow symlink */
		inode->i_op = &page_symlink_inode_operations;
		inode->i_mapping->a_ops = &ufs_aops;
		err = page_symlink(inode, symname, l);
		if (err)
			goto out_fail;
	} else {
		/* fast symlink */
		inode->i_op = &ufs_fast_symlink_inode_operations;
		memcpy(UFS_I(inode)->i_u1.i_symlink, symname, l);
		inode->i_size = l-1;
	}
	mark_inode_dirty(inode);

	err = ufs_add_nondir(dentry, inode);
out:
	unlock_kernel();
out_notlocked:
	return err;

out_fail:
	inode_dec_link_count(inode);
	iput(inode);
	goto out;
}

static int ufs_link (struct dentry * old_dentry, struct inode * dir,
	struct dentry *dentry)
{
	struct inode *inode = old_dentry->d_inode;
	int error;

	lock_kernel();
	if (inode->i_nlink >= UFS_LINK_MAX) {
		unlock_kernel();
		return -EMLINK;
	}

	inode->i_ctime = CURRENT_TIME_SEC;
	inode_inc_link_count(inode);
	atomic_inc(&inode->i_count);

	error = ufs_add_nondir(dentry, inode);
	unlock_kernel();
	return error;
}

static int ufs_mkdir(struct inode * dir, struct dentry * dentry, int mode)
{
	struct inode * inode;
	int err = -EMLINK;

	if (dir->i_nlink >= UFS_LINK_MAX)
		goto out;

	lock_kernel();
	inode_inc_link_count(dir);

	inode = ufs_new_inode(dir, S_IFDIR|mode);
	err = PTR_ERR(inode);
	if (IS_ERR(inode))
		goto out_dir;

	inode->i_op = &ufs_dir_inode_operations;
	inode->i_fop = &ufs_dir_operations;
	inode->i_mapping->a_ops = &ufs_aops;

	inode_inc_link_count(inode);

	err = ufs_make_empty(inode, dir);
	if (err)
		goto out_fail;

	err = ufs_add_link(dentry, inode);
	if (err)
		goto out_fail;
	unlock_kernel();

	d_instantiate(dentry, inode);
out:
	return err;

out_fail:
	inode_dec_link_count(inode);
	inode_dec_link_count(inode);
	iput (inode);
out_dir:
	inode_dec_link_count(dir);
	unlock_kernel();
	goto out;
}

static int ufs_unlink(struct inode *dir, struct dentry *dentry)
{
	struct inode * inode = dentry->d_inode;
	struct ufs_dir_entry *de;
	struct page *page;
	int err = -ENOENT;

	de = ufs_find_entry(dir, dentry, &page);
	if (!de)
		goto out;

	err = ufs_delete_entry(dir, de, page);
	if (err)
		goto out;

	inode->i_ctime = dir->i_ctime;
	inode_dec_link_count(inode);
	err = 0;
out:
	return err;
}

static int ufs_rmdir (struct inode * dir, struct dentry *dentry)
{
	struct inode * inode = dentry->d_inode;
	int err= -ENOTEMPTY;

	lock_kernel();
	if (ufs_empty_dir (inode)) {
		err = ufs_unlink(dir, dentry);
		if (!err) {
			inode->i_size = 0;
			inode_dec_link_count(inode);
			inode_dec_link_count(dir);
		}
	}
	unlock_kernel();
	return err;
}

static int ufs_rename(struct inode *old_dir, struct dentry *old_dentry,
		      struct inode *new_dir, struct dentry *new_dentry)
{
	struct inode *old_inode = old_dentry->d_inode;
	struct inode *new_inode = new_dentry->d_inode;
	struct page *dir_page = NULL;
	struct ufs_dir_entry * dir_de = NULL;
	struct page *old_page;
	struct ufs_dir_entry *old_de;
	int err = -ENOENT;

	old_de = ufs_find_entry(old_dir, old_dentry, &old_page);
	if (!old_de)
		goto out;

	if (S_ISDIR(old_inode->i_mode)) {
		err = -EIO;
		dir_de = ufs_dotdot(old_inode, &dir_page);
		if (!dir_de)
			goto out_old;
	}

	if (new_inode) {
		struct page *new_page;
		struct ufs_dir_entry *new_de;

		err = -ENOTEMPTY;
		if (dir_de && !ufs_empty_dir(new_inode))
			goto out_dir;

		err = -ENOENT;
		new_de = ufs_find_entry(new_dir, new_dentry, &new_page);
		if (!new_de)
			goto out_dir;
		inode_inc_link_count(old_inode);
		ufs_set_link(new_dir, new_de, new_page, old_inode);
		new_inode->i_ctime = CURRENT_TIME_SEC;
		if (dir_de)
			drop_nlink(new_inode);
		inode_dec_link_count(new_inode);
	} else {
		if (dir_de) {
			err = -EMLINK;
			if (new_dir->i_nlink >= UFS_LINK_MAX)
				goto out_dir;
		}
		inode_inc_link_count(old_inode);
		err = ufs_add_link(new_dentry, old_inode);
		if (err) {
			inode_dec_link_count(old_inode);
			goto out_dir;
		}
		if (dir_de)
			inode_inc_link_count(new_dir);
	}

	/*
	 * Like most other Unix systems, set the ctime for inodes on a
 	 * rename.
	 * inode_dec_link_count() will mark the inode dirty.
	 */
	old_inode->i_ctime = CURRENT_TIME_SEC;

	ufs_delete_entry(old_dir, old_de, old_page);
	inode_dec_link_count(old_inode);

	if (dir_de) {
		ufs_set_link(old_inode, dir_de, dir_page, new_dir);
		inode_dec_link_count(old_dir);
	}
	return 0;


out_dir:
	if (dir_de) {
		kunmap(dir_page);
		page_cache_release(dir_page);
	}
out_old:
	kunmap(old_page);
	page_cache_release(old_page);
out:
	return err;
}

const struct inode_operations ufs_dir_inode_operations = {
	.create		= ufs_create,
	.lookup		= ufs_lookup,
	.link		= ufs_link,
	.unlink		= ufs_unlink,
	.symlink	= ufs_symlink,
	.mkdir		= ufs_mkdir,
	.rmdir		= ufs_rmdir,
	.mknod		= ufs_mknod,
	.rename		= ufs_rename,
};
Commit	Line	Data
1da177e4 LT	1	/*
	2	* linux/fs/ufs/namei.c
	3	*
b71034e5 ED	4	* Migration to usage of "page cache" on May 2006 by
	5	* Evgeniy Dushistov <[email protected]> based on ext2 code base.
	6	*
1da177e4 LT	7	* Copyright (C) 1998
	8	* Daniel Pirkl <[email protected]>
	9	* Charles University, Faculty of Mathematics and Physics
	10	*
	11	* from
	12	*
	13	* linux/fs/ext2/namei.c
	14	*
	15	* Copyright (C) 1992, 1993, 1994, 1995
	16	* Remy Card ([email protected])
	17	* Laboratoire MASI - Institut Blaise Pascal
	18	* Universite Pierre et Marie Curie (Paris VI)
	19	*
	20	* from
	21	*
	22	* linux/fs/minix/namei.c
	23	*
	24	* Copyright (C) 1991, 1992 Linus Torvalds
	25	*
	26	* Big-endian to little-endian byte-swapping/bitmaps by
	27	* David S. Miller ([email protected]), 1995
	28	*/
	29
	30	#include <linux/time.h>
	31	#include <linux/fs.h>
1da177e4	32	#include <linux/smp_lock.h>
e5420598 MF	33
e5420598 MF	34	#include "ufs_fs.h"
bcd6d4ec	35	#include "ufs.h"
1da177e4 LT	36	#include "util.h"
1da177e4 LT	37
1da177e4 LT	38	static inline int ufs_add_nondir(struct dentry dentry, struct inode inode)
	39	{
	40	int err = ufs_add_link(dentry, inode);
	41	if (!err) {
	42	d_instantiate(dentry, inode);
	43	return 0;
	44	}
3257545e	45	inode_dec_link_count(inode);
1da177e4 LT	46	iput(inode);
	47	return err;
	48	}
	49
	50	static struct dentry ufs_lookup(struct inode dir, struct dentry dentry, struct nameidata nd)
	51	{
	52	struct inode * inode = NULL;
	53	ino_t ino;
	54
	55	if (dentry->d_name.len > UFS_MAXNAMLEN)
	56	return ERR_PTR(-ENAMETOOLONG);
	57
	58	lock_kernel();
	59	ino = ufs_inode_by_name(dir, dentry);
	60	if (ino) {
b55c460d DH	61	inode = ufs_iget(dir->i_sb, ino);
b55c460d DH	62	if (IS_ERR(inode)) {
1da177e4	63	unlock_kernel();
b55c460d	64	return ERR_CAST(inode);
1da177e4 LT	65	}
	66	}
	67	unlock_kernel();
	68	d_add(dentry, inode);
	69	return NULL;
	70	}
	71
	72	/*
	73	* By the time this is called, we already have created
	74	* the directory cache entry for the new file, but it
	75	* is so far negative - it has no inode.
	76	*
	77	* If the create succeeds, we fill in the inode information
	78	* with d_instantiate().
	79	*/
	80	static int ufs_create (struct inode * dir, struct dentry * dentry, int mode,
	81	struct nameidata *nd)
	82	{
abf5d15f ED	83	struct inode *inode;
	84	int err;
	85
	86	UFSD("BEGIN\n");
	87	inode = ufs_new_inode(dir, mode);
	88	err = PTR_ERR(inode);
	89
1da177e4 LT	90	if (!IS_ERR(inode)) {
	91	inode->i_op = &ufs_file_inode_operations;
	92	inode->i_fop = &ufs_file_operations;
	93	inode->i_mapping->a_ops = &ufs_aops;
	94	mark_inode_dirty(inode);
	95	lock_kernel();
	96	err = ufs_add_nondir(dentry, inode);
	97	unlock_kernel();
	98	}
abf5d15f	99	UFSD("END: err=%d\n", err);
1da177e4 LT	100	return err;
	101	}
	102
	103	static int ufs_mknod (struct inode * dir, struct dentry *dentry, int mode, dev_t rdev)
	104	{
	105	struct inode *inode;
	106	int err;
	107
	108	if (!old_valid_dev(rdev))
	109	return -EINVAL;
	110	inode = ufs_new_inode(dir, mode);
	111	err = PTR_ERR(inode);
	112	if (!IS_ERR(inode)) {
	113	init_special_inode(inode, mode, rdev);
1da177e4 LT	114	ufs_set_inode_dev(inode->i_sb, UFS_I(inode), rdev);
	115	mark_inode_dirty(inode);
	116	lock_kernel();
	117	err = ufs_add_nondir(dentry, inode);
	118	unlock_kernel();
	119	}
	120	return err;
	121	}
	122
	123	static int ufs_symlink (struct inode * dir, struct dentry * dentry,
	124	const char * symname)
	125	{
	126	struct super_block * sb = dir->i_sb;
	127	int err = -ENAMETOOLONG;
	128	unsigned l = strlen(symname)+1;
	129	struct inode * inode;
	130
	131	if (l > sb->s_blocksize)
344fe786	132	goto out_notlocked;
1da177e4 LT	133
	134	lock_kernel();
	135	inode = ufs_new_inode(dir, S_IFLNK \| S_IRWXUGO);
	136	err = PTR_ERR(inode);
	137	if (IS_ERR(inode))
	138	goto out;
	139
	140	if (l > UFS_SB(sb)->s_uspi->s_maxsymlinklen) {
	141	/* slow symlink */
	142	inode->i_op = &page_symlink_inode_operations;
	143	inode->i_mapping->a_ops = &ufs_aops;
	144	err = page_symlink(inode, symname, l);
	145	if (err)
	146	goto out_fail;
	147	} else {
	148	/* fast symlink */
	149	inode->i_op = &ufs_fast_symlink_inode_operations;
723be1f3	150	memcpy(UFS_I(inode)->i_u1.i_symlink, symname, l);
1da177e4 LT	151	inode->i_size = l-1;
	152	}
	153	mark_inode_dirty(inode);
	154
	155	err = ufs_add_nondir(dentry, inode);
	156	out:
	157	unlock_kernel();
344fe786	158	out_notlocked:
1da177e4 LT	159	return err;
	160
	161	out_fail:
3257545e	162	inode_dec_link_count(inode);
1da177e4 LT	163	iput(inode);
	164	goto out;
	165	}
	166
	167	static int ufs_link (struct dentry * old_dentry, struct inode * dir,
	168	struct dentry *dentry)
	169	{
	170	struct inode *inode = old_dentry->d_inode;
	171	int error;
	172
	173	lock_kernel();
	174	if (inode->i_nlink >= UFS_LINK_MAX) {
	175	unlock_kernel();
	176	return -EMLINK;
	177	}
	178
	179	inode->i_ctime = CURRENT_TIME_SEC;
3257545e	180	inode_inc_link_count(inode);
1da177e4 LT	181	atomic_inc(&inode->i_count);
	182
	183	error = ufs_add_nondir(dentry, inode);
	184	unlock_kernel();
	185	return error;
	186	}
	187
	188	static int ufs_mkdir(struct inode * dir, struct dentry * dentry, int mode)
	189	{
	190	struct inode * inode;
	191	int err = -EMLINK;
	192
	193	if (dir->i_nlink >= UFS_LINK_MAX)
	194	goto out;
	195
	196	lock_kernel();
3257545e	197	inode_inc_link_count(dir);
1da177e4 LT	198
	199	inode = ufs_new_inode(dir, S_IFDIR\|mode);
	200	err = PTR_ERR(inode);
	201	if (IS_ERR(inode))
	202	goto out_dir;
	203
	204	inode->i_op = &ufs_dir_inode_operations;
	205	inode->i_fop = &ufs_dir_operations;
826843a3	206	inode->i_mapping->a_ops = &ufs_aops;
1da177e4	207
3257545e	208	inode_inc_link_count(inode);
1da177e4 LT	209
	210	err = ufs_make_empty(inode, dir);
	211	if (err)
	212	goto out_fail;
	213
	214	err = ufs_add_link(dentry, inode);
	215	if (err)
	216	goto out_fail;
	217	unlock_kernel();
	218
	219	d_instantiate(dentry, inode);
	220	out:
	221	return err;
	222
	223	out_fail:
3257545e AD	224	inode_dec_link_count(inode);
3257545e AD	225	inode_dec_link_count(inode);
1da177e4 LT	226	iput (inode);
1da177e4 LT	227	out_dir:
3257545e	228	inode_dec_link_count(dir);
1da177e4 LT	229	unlock_kernel();
	230	goto out;
	231	}
	232
b71034e5	233	static int ufs_unlink(struct inode dir, struct dentry dentry)
1da177e4 LT	234	{
1da177e4 LT	235	struct inode * inode = dentry->d_inode;
b71034e5 ED	236	struct ufs_dir_entry *de;
b71034e5 ED	237	struct page *page;
1da177e4 LT	238	int err = -ENOENT;
1da177e4 LT	239
b71034e5	240	de = ufs_find_entry(dir, dentry, &page);
1da177e4 LT	241	if (!de)
	242	goto out;
	243
b71034e5	244	err = ufs_delete_entry(dir, de, page);
1da177e4 LT	245	if (err)
	246	goto out;
	247
	248	inode->i_ctime = dir->i_ctime;
3257545e	249	inode_dec_link_count(inode);
1da177e4 LT	250	err = 0;
1da177e4 LT	251	out:
1da177e4 LT	252	return err;
	253	}
	254
	255	static int ufs_rmdir (struct inode * dir, struct dentry *dentry)
	256	{
	257	struct inode * inode = dentry->d_inode;
	258	int err= -ENOTEMPTY;
	259
	260	lock_kernel();
	261	if (ufs_empty_dir (inode)) {
	262	err = ufs_unlink(dir, dentry);
	263	if (!err) {
	264	inode->i_size = 0;
3257545e AD	265	inode_dec_link_count(inode);
3257545e AD	266	inode_dec_link_count(dir);
1da177e4 LT	267	}
	268	}
	269	unlock_kernel();
	270	return err;
	271	}
	272
b71034e5 ED	273	static int ufs_rename(struct inode old_dir, struct dentry old_dentry,
b71034e5 ED	274	struct inode new_dir, struct dentry new_dentry)
1da177e4 LT	275	{
	276	struct inode *old_inode = old_dentry->d_inode;
	277	struct inode *new_inode = new_dentry->d_inode;
b71034e5 ED	278	struct page *dir_page = NULL;
	279	struct ufs_dir_entry * dir_de = NULL;
	280	struct page *old_page;
1da177e4 LT	281	struct ufs_dir_entry *old_de;
	282	int err = -ENOENT;
	283
b71034e5	284	old_de = ufs_find_entry(old_dir, old_dentry, &old_page);
1da177e4 LT	285	if (!old_de)
	286	goto out;
	287
	288	if (S_ISDIR(old_inode->i_mode)) {
	289	err = -EIO;
b71034e5	290	dir_de = ufs_dotdot(old_inode, &dir_page);
1da177e4 LT	291	if (!dir_de)
	292	goto out_old;
	293	}
	294
	295	if (new_inode) {
b71034e5	296	struct page *new_page;
1da177e4 LT	297	struct ufs_dir_entry *new_de;
	298
	299	err = -ENOTEMPTY;
b71034e5	300	if (dir_de && !ufs_empty_dir(new_inode))
1da177e4	301	goto out_dir;
b71034e5	302
1da177e4	303	err = -ENOENT;
b71034e5	304	new_de = ufs_find_entry(new_dir, new_dentry, &new_page);
1da177e4 LT	305	if (!new_de)
1da177e4 LT	306	goto out_dir;
3257545e	307	inode_inc_link_count(old_inode);
b71034e5	308	ufs_set_link(new_dir, new_de, new_page, old_inode);
1da177e4 LT	309	new_inode->i_ctime = CURRENT_TIME_SEC;
1da177e4 LT	310	if (dir_de)
9a53c3a7	311	drop_nlink(new_inode);
3257545e	312	inode_dec_link_count(new_inode);
1da177e4 LT	313	} else {
	314	if (dir_de) {
	315	err = -EMLINK;
	316	if (new_dir->i_nlink >= UFS_LINK_MAX)
	317	goto out_dir;
	318	}
3257545e	319	inode_inc_link_count(old_inode);
1da177e4 LT	320	err = ufs_add_link(new_dentry, old_inode);
1da177e4 LT	321	if (err) {
3257545e	322	inode_dec_link_count(old_inode);
1da177e4 LT	323	goto out_dir;
	324	}
	325	if (dir_de)
3257545e	326	inode_inc_link_count(new_dir);
1da177e4 LT	327	}
1da177e4 LT	328
b71034e5 ED	329	/*
	330	* Like most other Unix systems, set the ctime for inodes on a
	331	* rename.
	332	* inode_dec_link_count() will mark the inode dirty.
	333	*/
	334	old_inode->i_ctime = CURRENT_TIME_SEC;
1da177e4	335
b71034e5	336	ufs_delete_entry(old_dir, old_de, old_page);
3257545e	337	inode_dec_link_count(old_inode);
1da177e4 LT	338
1da177e4 LT	339	if (dir_de) {
b71034e5	340	ufs_set_link(old_inode, dir_de, dir_page, new_dir);
3257545e	341	inode_dec_link_count(old_dir);
1da177e4	342	}
1da177e4 LT	343	return 0;
1da177e4 LT	344
b71034e5	345
1da177e4	346	out_dir:
b71034e5 ED	347	if (dir_de) {
	348	kunmap(dir_page);
	349	page_cache_release(dir_page);
	350	}
1da177e4	351	out_old:
b71034e5 ED	352	kunmap(old_page);
b71034e5 ED	353	page_cache_release(old_page);
1da177e4	354	out:
1da177e4 LT	355	return err;
	356	}
	357
c5ef1c42	358	const struct inode_operations ufs_dir_inode_operations = {
1da177e4 LT	359	.create = ufs_create,
	360	.lookup = ufs_lookup,
	361	.link = ufs_link,
	362	.unlink = ufs_unlink,
	363	.symlink = ufs_symlink,
	364	.mkdir = ufs_mkdir,
	365	.rmdir = ufs_rmdir,
	366	.mknod = ufs_mknod,
	367	.rename = ufs_rename,
	368	};