[net-next-2.6.git] / fs / ufs / namei.c

/*
 * linux/fs/ufs/namei.c
 *
 * Migration to usage of "page cache" on May 2006 by
 * Evgeniy Dushistov <dushistov@mail.ru> based on ext2 code base.
 *
 * Copyright (C) 1998
 * Daniel Pirkl <daniel.pirkl@email.cz>
 * Charles University, Faculty of Mathematics and Physics
 *
 *  from
 *
 *  linux/fs/ext2/namei.c
 *
 * Copyright (C) 1992, 1993, 1994, 1995
 * Remy Card (card@masi.ibp.fr)
 * 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 (davem@caip.rutgers.edu), 1995
 */

#include <linux/time.h>
#include <linux/fs.h>
#include <linux/ufs_fs.h>
#include <linux/smp_lock.h>
#include "swab.h"	/* will go away - see comment in mknod() */
#include "util.h"

/*
#undef UFS_NAMEI_DEBUG
*/
#define UFS_NAMEI_DEBUG

#ifdef UFS_NAMEI_DEBUG
#define UFSD(x) printk("(%s, %d), %s: ", __FILE__, __LINE__, __FUNCTION__); printk x;
#else
#define UFSD(x)
#endif

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 = iget(dir->i_sb, ino);
		if (!inode) {
			unlock_kernel();
			return ERR_PTR(-EACCES);
		}
	}
	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 = ufs_new_inode(dir, mode);
	int 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();
	}
	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);
		/* NOTE: that'll go when we get wide dev_t */
		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;

	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((char*)&UFS_I(inode)->i_u1.i_data,symname,l);
		inode->i_size = l-1;
	}
	mark_inode_dirty(inode);

	err = ufs_add_nondir(dentry, inode);
out:
	unlock_kernel();
	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)
			new_inode->i_nlink--;
		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;
}

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 <dushistov@mail.ru> based on ext2 code base.
	6	*
1da177e4 LT	7	* Copyright (C) 1998
	8	* Daniel Pirkl <daniel.pirkl@email.cz>
	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 (card@masi.ibp.fr)
	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 (davem@caip.rutgers.edu), 1995
	28	*/
	29
	30	#include <linux/time.h>
	31	#include <linux/fs.h>
	32	#include <linux/ufs_fs.h>
	33	#include <linux/smp_lock.h>
1da177e4 LT	34	#include "swab.h" /* will go away - see comment in mknod() */
	35	#include "util.h"
	36
	37	/*
	38	#undef UFS_NAMEI_DEBUG
	39	*/
	40	#define UFS_NAMEI_DEBUG
	41
	42	#ifdef UFS_NAMEI_DEBUG
	43	#define UFSD(x) printk("(%s, %d), %s: ", __FILE__, __LINE__, __FUNCTION__); printk x;
	44	#else
	45	#define UFSD(x)
	46	#endif
	47
1da177e4 LT	48	static inline int ufs_add_nondir(struct dentry dentry, struct inode inode)
	49	{
	50	int err = ufs_add_link(dentry, inode);
	51	if (!err) {
	52	d_instantiate(dentry, inode);
	53	return 0;
	54	}
3257545e	55	inode_dec_link_count(inode);
1da177e4 LT	56	iput(inode);
	57	return err;
	58	}
	59
	60	static struct dentry ufs_lookup(struct inode dir, struct dentry dentry, struct nameidata nd)
	61	{
	62	struct inode * inode = NULL;
	63	ino_t ino;
	64
	65	if (dentry->d_name.len > UFS_MAXNAMLEN)
	66	return ERR_PTR(-ENAMETOOLONG);
	67
	68	lock_kernel();
	69	ino = ufs_inode_by_name(dir, dentry);
	70	if (ino) {
	71	inode = iget(dir->i_sb, ino);
	72	if (!inode) {
	73	unlock_kernel();
	74	return ERR_PTR(-EACCES);
	75	}
	76	}
	77	unlock_kernel();
	78	d_add(dentry, inode);
	79	return NULL;
	80	}
	81
	82	/*
	83	* By the time this is called, we already have created
	84	* the directory cache entry for the new file, but it
	85	* is so far negative - it has no inode.
	86	*
	87	* If the create succeeds, we fill in the inode information
	88	* with d_instantiate().
	89	*/
	90	static int ufs_create (struct inode * dir, struct dentry * dentry, int mode,
	91	struct nameidata *nd)
	92	{
	93	struct inode * inode = ufs_new_inode(dir, mode);
	94	int err = PTR_ERR(inode);
	95	if (!IS_ERR(inode)) {
	96	inode->i_op = &ufs_file_inode_operations;
	97	inode->i_fop = &ufs_file_operations;
	98	inode->i_mapping->a_ops = &ufs_aops;
	99	mark_inode_dirty(inode);
	100	lock_kernel();
	101	err = ufs_add_nondir(dentry, inode);
	102	unlock_kernel();
	103	}
	104	return err;
	105	}
	106
	107	static int ufs_mknod (struct inode * dir, struct dentry *dentry, int mode, dev_t rdev)
	108	{
	109	struct inode *inode;
	110	int err;
	111
	112	if (!old_valid_dev(rdev))
	113	return -EINVAL;
	114	inode = ufs_new_inode(dir, mode);
	115	err = PTR_ERR(inode);
	116	if (!IS_ERR(inode)) {
	117	init_special_inode(inode, mode, rdev);
	118	/* NOTE: that'll go when we get wide dev_t */
	119	ufs_set_inode_dev(inode->i_sb, UFS_I(inode), rdev);
120	mark_inode_dirty(inode);
121	lock_kernel();
122	err = ufs_add_nondir(dentry, inode);
123	unlock_kernel();
124	}
125	return err;
126	}
127
128	static int ufs_symlink (struct inode * dir, struct dentry * dentry,
129	const char * symname)
130	{
131	struct super_block * sb = dir->i_sb;
132	int err = -ENAMETOOLONG;
133	unsigned l = strlen(symname)+1;
134	struct inode * inode;
135
136	if (l > sb->s_blocksize)
137	goto out;
138
139	lock_kernel();
140	inode = ufs_new_inode(dir, S_IFLNK \| S_IRWXUGO);
141	err = PTR_ERR(inode);
142	if (IS_ERR(inode))
143	goto out;
144
145	if (l > UFS_SB(sb)->s_uspi->s_maxsymlinklen) {
146	/* slow symlink */
147	inode->i_op = &page_symlink_inode_operations;
148	inode->i_mapping->a_ops = &ufs_aops;
149	err = page_symlink(inode, symname, l);
150	if (err)
151	goto out_fail;
152	} else {
153	/* fast symlink */
154	inode->i_op = &ufs_fast_symlink_inode_operations;
155	memcpy((char*)&UFS_I(inode)->i_u1.i_data,symname,l);
156	inode->i_size = l-1;
157	}
158	mark_inode_dirty(inode);
159
160	err = ufs_add_nondir(dentry, inode);
161	out:
162	unlock_kernel();
163	return err;
164
165	out_fail:
3257545e	166	inode_dec_link_count(inode);
1da177e4 LT	167	iput(inode);
	168	goto out;
	169	}
	170
	171	static int ufs_link (struct dentry * old_dentry, struct inode * dir,
	172	struct dentry *dentry)
	173	{
	174	struct inode *inode = old_dentry->d_inode;
	175	int error;
	176
	177	lock_kernel();
	178	if (inode->i_nlink >= UFS_LINK_MAX) {
	179	unlock_kernel();
	180	return -EMLINK;
	181	}
	182
	183	inode->i_ctime = CURRENT_TIME_SEC;
3257545e	184	inode_inc_link_count(inode);
1da177e4 LT	185	atomic_inc(&inode->i_count);
	186
	187	error = ufs_add_nondir(dentry, inode);
	188	unlock_kernel();
	189	return error;
	190	}
	191
	192	static int ufs_mkdir(struct inode * dir, struct dentry * dentry, int mode)
	193	{
	194	struct inode * inode;
	195	int err = -EMLINK;
	196
	197	if (dir->i_nlink >= UFS_LINK_MAX)
	198	goto out;
	199
	200	lock_kernel();
3257545e	201	inode_inc_link_count(dir);
1da177e4 LT	202
	203	inode = ufs_new_inode(dir, S_IFDIR\|mode);
	204	err = PTR_ERR(inode);
	205	if (IS_ERR(inode))
	206	goto out_dir;
	207
	208	inode->i_op = &ufs_dir_inode_operations;
	209	inode->i_fop = &ufs_dir_operations;
826843a3	210	inode->i_mapping->a_ops = &ufs_aops;
1da177e4	211
3257545e	212	inode_inc_link_count(inode);
1da177e4 LT	213
	214	err = ufs_make_empty(inode, dir);
	215	if (err)
	216	goto out_fail;
	217
	218	err = ufs_add_link(dentry, inode);
	219	if (err)
	220	goto out_fail;
	221	unlock_kernel();
	222
	223	d_instantiate(dentry, inode);
	224	out:
	225	return err;
	226
	227	out_fail:
3257545e AD	228	inode_dec_link_count(inode);
3257545e AD	229	inode_dec_link_count(inode);
1da177e4 LT	230	iput (inode);
1da177e4 LT	231	out_dir:
3257545e	232	inode_dec_link_count(dir);
1da177e4 LT	233	unlock_kernel();
	234	goto out;
	235	}
	236
b71034e5	237	static int ufs_unlink(struct inode dir, struct dentry dentry)
1da177e4 LT	238	{
1da177e4 LT	239	struct inode * inode = dentry->d_inode;
b71034e5 ED	240	struct ufs_dir_entry *de;
b71034e5 ED	241	struct page *page;
1da177e4 LT	242	int err = -ENOENT;
1da177e4 LT	243
b71034e5	244	de = ufs_find_entry(dir, dentry, &page);
1da177e4 LT	245	if (!de)
	246	goto out;
	247
b71034e5	248	err = ufs_delete_entry(dir, de, page);
1da177e4 LT	249	if (err)
	250	goto out;
	251
	252	inode->i_ctime = dir->i_ctime;
3257545e	253	inode_dec_link_count(inode);
1da177e4 LT	254	err = 0;
1da177e4 LT	255	out:
1da177e4 LT	256	return err;
	257	}
	258
	259	static int ufs_rmdir (struct inode * dir, struct dentry *dentry)
	260	{
	261	struct inode * inode = dentry->d_inode;
	262	int err= -ENOTEMPTY;
	263
	264	lock_kernel();
	265	if (ufs_empty_dir (inode)) {
	266	err = ufs_unlink(dir, dentry);
	267	if (!err) {
	268	inode->i_size = 0;
3257545e AD	269	inode_dec_link_count(inode);
3257545e AD	270	inode_dec_link_count(dir);
1da177e4 LT	271	}
	272	}
	273	unlock_kernel();
	274	return err;
	275	}
	276
b71034e5 ED	277	static int ufs_rename(struct inode old_dir, struct dentry old_dentry,
b71034e5 ED	278	struct inode new_dir, struct dentry new_dentry)
1da177e4 LT	279	{
	280	struct inode *old_inode = old_dentry->d_inode;
	281	struct inode *new_inode = new_dentry->d_inode;
b71034e5 ED	282	struct page *dir_page = NULL;
	283	struct ufs_dir_entry * dir_de = NULL;
	284	struct page *old_page;
1da177e4 LT	285	struct ufs_dir_entry *old_de;
	286	int err = -ENOENT;
	287
b71034e5	288	old_de = ufs_find_entry(old_dir, old_dentry, &old_page);
1da177e4 LT	289	if (!old_de)
	290	goto out;
	291
	292	if (S_ISDIR(old_inode->i_mode)) {
	293	err = -EIO;
b71034e5	294	dir_de = ufs_dotdot(old_inode, &dir_page);
1da177e4 LT	295	if (!dir_de)
	296	goto out_old;
	297	}
	298
	299	if (new_inode) {
b71034e5	300	struct page *new_page;
1da177e4 LT	301	struct ufs_dir_entry *new_de;
	302
	303	err = -ENOTEMPTY;
b71034e5	304	if (dir_de && !ufs_empty_dir(new_inode))
1da177e4	305	goto out_dir;
b71034e5	306
1da177e4	307	err = -ENOENT;
b71034e5	308	new_de = ufs_find_entry(new_dir, new_dentry, &new_page);
1da177e4 LT	309	if (!new_de)
1da177e4 LT	310	goto out_dir;
3257545e	311	inode_inc_link_count(old_inode);
b71034e5	312	ufs_set_link(new_dir, new_de, new_page, old_inode);
1da177e4 LT	313	new_inode->i_ctime = CURRENT_TIME_SEC;
	314	if (dir_de)
	315	new_inode->i_nlink--;
3257545e	316	inode_dec_link_count(new_inode);
1da177e4 LT	317	} else {
	318	if (dir_de) {
	319	err = -EMLINK;
	320	if (new_dir->i_nlink >= UFS_LINK_MAX)
	321	goto out_dir;
	322	}
3257545e	323	inode_inc_link_count(old_inode);
1da177e4 LT	324	err = ufs_add_link(new_dentry, old_inode);
1da177e4 LT	325	if (err) {
3257545e	326	inode_dec_link_count(old_inode);
1da177e4 LT	327	goto out_dir;
	328	}
	329	if (dir_de)
3257545e	330	inode_inc_link_count(new_dir);
1da177e4 LT	331	}
1da177e4 LT	332
b71034e5 ED	333	/*
	334	* Like most other Unix systems, set the ctime for inodes on a
	335	* rename.
	336	* inode_dec_link_count() will mark the inode dirty.
	337	*/
	338	old_inode->i_ctime = CURRENT_TIME_SEC;
1da177e4	339
b71034e5	340	ufs_delete_entry(old_dir, old_de, old_page);
3257545e	341	inode_dec_link_count(old_inode);
1da177e4 LT	342
1da177e4 LT	343	if (dir_de) {
b71034e5	344	ufs_set_link(old_inode, dir_de, dir_page, new_dir);
3257545e	345	inode_dec_link_count(old_dir);
1da177e4	346	}
1da177e4 LT	347	return 0;
1da177e4 LT	348
b71034e5	349
1da177e4	350	out_dir:
b71034e5 ED	351	if (dir_de) {
	352	kunmap(dir_page);
	353	page_cache_release(dir_page);
	354	}
1da177e4	355	out_old:
b71034e5 ED	356	kunmap(old_page);
b71034e5 ED	357	page_cache_release(old_page);
1da177e4	358	out:
1da177e4 LT	359	return err;
	360	}
	361
	362	struct inode_operations ufs_dir_inode_operations = {
	363	.create = ufs_create,
	364	.lookup = ufs_lookup,
	365	.link = ufs_link,
	366	.unlink = ufs_unlink,
	367	.symlink = ufs_symlink,
	368	.mkdir = ufs_mkdir,
	369	.rmdir = ufs_rmdir,
	370	.mknod = ufs_mknod,
	371	.rename = ufs_rename,
	372	};