patch-2.4.6 linux/fs/sysv/namei.c

• Lines: 801
• Date: Mon Jul 2 14:03:04 2001
• Orig file: v2.4.5/linux/fs/sysv/namei.c
• Orig date: Tue Sep 5 14:07:30 2000

diff -u --recursive --new-file v2.4.5/linux/fs/sysv/namei.c linux/fs/sysv/namei.c
@@ -12,108 +12,70 @@
  *  Copyright (C) 1997, 1998  Krzysztof G. Baranowski
  */
 
-
-#include <linux/sched.h>
-#include <linux/kernel.h>
 #include <linux/fs.h>
 #include <linux/sysv_fs.h>
-#include <linux/string.h>
-#include <linux/stat.h>
-#include <linux/errno.h>
+#include <linux/pagemap.h>
 
-/* compare strings: name[0..len-1] (not zero-terminated) and
- * buffer[0..] (filled with zeroes up to buffer[0..maxlen-1])
- */
-static inline int namecompare(int len, int maxlen,
-	const char * name, const char * buffer)
+static inline void inc_count(struct inode *inode)
 {
-	if (len > maxlen)
-		return 0;
-	if (len < maxlen && buffer[len])
-		return 0;
-	return !memcmp(name, buffer, len);
+	inode->i_nlink++;
+	mark_inode_dirty(inode);
 }
 
-/*
- * ok, we cannot use strncmp, as the name is not in our data space. [Now it is!]
- * Thus we'll have to use sysv_match. No big problem. Match also makes
- * some sanity tests.
- *
- * NOTE! unlike strncmp, sysv_match returns 1 for success, 0 for failure.
- */
-static int sysv_match(int len, const char * name, struct sysv_dir_entry * de)
+static inline void dec_count(struct inode *inode)
 {
-	if (!de->inode || len > SYSV_NAMELEN)
-		return 0;
-	/* "" means "." ---> so paths like "/usr/lib//libc.a" work */
-	if (!len && (de->name[0]=='.') && (de->name[1]=='\0'))
-		return 1;
-	return namecompare(len, SYSV_NAMELEN, name, de->name);
+	inode->i_nlink--;
+	mark_inode_dirty(inode);
 }
 
-/*
- *	sysv_find_entry()
- *
- * finds an entry in the specified directory with the wanted name. It
- * returns the cache buffer in which the entry was found, and the entry
- * itself (as a parameter - res_dir). It does NOT read the inode of the
- * entry - you'll have to do that yourself if you want to.
- */
-static struct buffer_head * sysv_find_entry(struct inode * dir,
-	const char * name, int namelen, struct sysv_dir_entry ** res_dir)
+static int add_nondir(struct dentry *dentry, struct inode *inode)
 {
-	struct super_block * sb;
-	unsigned long pos, block, offset; /* pos = block * block_size + offset */
-	struct buffer_head * bh;
-
-	*res_dir = NULL;
-	sb = dir->i_sb;
-	if (namelen > SYSV_NAMELEN) {
-		if (sb->sv_truncate)
-			namelen = SYSV_NAMELEN;
-		else
-			return NULL;
-	}
-	bh = NULL;
-	pos = block = offset = 0;
-	while (pos < dir->i_size) {
-		if (!bh) {
-			bh = sysv_file_bread(dir, block, 0);
-			if (!bh) {
-				/* offset = 0; */ block++;
-				pos += sb->sv_block_size;
-				continue;
-			}
-		}
-		if (sysv_match(namelen, name,
-			       *res_dir = (struct sysv_dir_entry *) (bh->b_data + offset) ))
-			return bh;
-		pos += SYSV_DIRSIZE;
-		offset += SYSV_DIRSIZE;
-		if (offset < sb->sv_block_size)
-			continue;
-		brelse(bh);
-		bh = NULL;
-		offset = 0; block++;
+	int err = sysv_add_link(dentry, inode);
+	if (!err) {
+		d_instantiate(dentry, inode);
+		return 0;
 	}
-	brelse(bh);
-	*res_dir = NULL;
-	return NULL;
+	dec_count(inode);
+	iput(inode);
+	return err;
 }
 
+static int sysv_hash(struct dentry *dentry, struct qstr *qstr)
+{
+	unsigned long hash;
+	int i;
+	const unsigned char *name;
+
+	i = SYSV_NAMELEN;
+	if (i >= qstr->len)
+		return 0;
+	/* Truncate the name in place, avoids having to define a compare
+	   function. */
+	qstr->len = i;
+	name = qstr->name;
+	hash = init_name_hash();
+	while (i--)
+		hash = partial_name_hash(*name++, hash);
+	qstr->hash = end_name_hash(hash);
+	return 0;
+}
+
+struct dentry_operations sysv_dentry_operations = {
+	d_hash:		sysv_hash,
+};
+
 static struct dentry *sysv_lookup(struct inode * dir, struct dentry * dentry)
 {
 	struct inode * inode = NULL;
-	struct sysv_dir_entry * de;
-	struct buffer_head * bh;
+	ino_t ino;
 
-	bh = sysv_find_entry(dir, dentry->d_name.name, dentry->d_name.len, &de);
+	dentry->d_op = dir->i_sb->s_root->d_op;
+	if (dentry->d_name.len > SYSV_NAMELEN)
+		return ERR_PTR(-ENAMETOOLONG);
+	ino = sysv_inode_by_name(dentry);
 
-	if (bh) {
-		int ino = de->inode;
-		brelse(bh);
+	if (ino) {
 		inode = iget(dir->i_sb, ino);
-	
 		if (!inode) 
 			return ERR_PTR(-EACCES);
 	}
@@ -121,399 +83,146 @@
 	return NULL;
 }
 
-/*
- *	sysv_add_entry()
- *
- * adds a file entry to the specified directory, returning a possible
- * error value if it fails.
- *
- * NOTE!! The inode part of 'de' is left at 0 - which means you
- * may not sleep between calling this and putting something into
- * the entry, as someone else might have used it while you slept.
- */
-static int sysv_add_entry(struct inode * dir,
-	const char * name, int namelen,
-	struct buffer_head ** res_buf,
-	struct sysv_dir_entry ** res_dir)
+static int sysv_mknod(struct inode * dir, struct dentry * dentry, int mode, int rdev)
 {
-	struct super_block * sb;
-	int i;
-	unsigned long pos, block, offset; /* pos = block * block_size + offset */
-	struct buffer_head * bh;
-	struct sysv_dir_entry * de;
-
-	*res_buf = NULL;
-	*res_dir = NULL;
-	sb = dir->i_sb;
-	if (namelen > SYSV_NAMELEN) {
-		if (sb->sv_truncate)
-			namelen = SYSV_NAMELEN;
-		else
-			return -ENAMETOOLONG;
-	}
-	if (!namelen)
-		return -ENOENT;
-	bh = NULL;
-	pos = block = offset = 0;
-	while (1) {
-		if (!bh) {
-			bh = sysv_file_bread(dir, block, 1);
-			if (!bh)
-				return -ENOSPC;
-		}
-		de = (struct sysv_dir_entry *) (bh->b_data + offset);
-		pos += SYSV_DIRSIZE;
-		offset += SYSV_DIRSIZE;
-		if (pos > dir->i_size) {
-			de->inode = 0;
-			dir->i_size = pos;
-			mark_inode_dirty(dir);
-		}
-		if (de->inode) {
-			if (namecompare(namelen, SYSV_NAMELEN, name, de->name)) {
-				brelse(bh);
-				return -EEXIST;
-			}
-		} else {
-			dir->i_mtime = dir->i_ctime = CURRENT_TIME;
-			mark_inode_dirty(dir);
-			for (i = 0; i < SYSV_NAMELEN ; i++)
-				de->name[i] = (i < namelen) ? name[i] : 0;
-			mark_buffer_dirty(bh);
-			*res_dir = de;
-			break;
-		}
-		if (offset < sb->sv_block_size)
-			continue;
-		brelse(bh);
-		bh = NULL;
-		offset = 0; block++;
-	}
-	*res_buf = bh;
-	return 0;
+	struct inode * inode = sysv_new_inode(dir, mode);
+	if (!inode)
+		return -ENOSPC;
+	sysv_set_inode(inode, rdev);
+	mark_inode_dirty(inode);
+	return add_nondir(dentry, inode);
 }
 
 static int sysv_create(struct inode * dir, struct dentry * dentry, int mode)
 {
-	int error;
-	struct inode * inode;
-	struct buffer_head * bh;
-	struct sysv_dir_entry * de;
-
-	inode = sysv_new_inode(dir);
-	if (!inode) 
-		return -ENOSPC;
-	inode->i_op = &sysv_file_inode_operations;
-	inode->i_fop = &sysv_file_operations;
-	inode->i_mapping->a_ops = &sysv_aops;
-	inode->i_mode = mode;
-	mark_inode_dirty(inode);
-	error = sysv_add_entry(dir, dentry->d_name.name,
-			       dentry->d_name.len, &bh, &de);
-	if (error) {
-		inode->i_nlink--;
-		mark_inode_dirty(inode);
-		iput(inode);
-		return error;
-	}
-	de->inode = inode->i_ino;
-	mark_buffer_dirty(bh);
-	brelse(bh);
-	d_instantiate(dentry, inode);
-	return 0;
+	return sysv_mknod(dir, dentry, mode, 0);
 }
 
-static int sysv_mknod(struct inode * dir, struct dentry * dentry, int mode, int rdev)
+static int sysv_symlink(struct inode * dir, struct dentry * dentry, 
+	const char * symname)
 {
-	int error;
+	int err = -ENAMETOOLONG;
+	int l = strlen(symname)+1;
 	struct inode * inode;
-	struct buffer_head * bh;
-	struct sysv_dir_entry * de;
 
-	bh = sysv_find_entry(dir, dentry->d_name.name,
-			     dentry->d_name.len, &de);
-	if (bh) {
-		brelse(bh);
-		return -EEXIST;
-	}
-	inode = sysv_new_inode(dir);
+	if (l > dir->i_sb->s_blocksize)
+		goto out;
+
+	err = -ENOSPC;
+	inode = sysv_new_inode(dir, S_IFLNK|0777);
 	if (!inode)
-		return -ENOSPC;
-	inode->i_uid = current->fsuid;
-	init_special_inode(inode, mode, rdev);
-	mark_inode_dirty(inode);
-	error = sysv_add_entry(dir, dentry->d_name.name, 
-			       dentry->d_name.len, &bh, &de);
-	if (error) {
-		inode->i_nlink--;
-		mark_inode_dirty(inode);
-		iput(inode);
-		return error;
-	}
-	de->inode = inode->i_ino;
-	mark_buffer_dirty(bh);
-	brelse(bh);
-	d_instantiate(dentry, inode);
-	return 0;
+		goto out;
+
+	sysv_set_inode(inode, 0);
+	err = block_symlink(inode, symname, l);
+	if (err)
+		goto out_fail;
+
+	err = add_nondir(dentry, inode);
+out:
+	return err;
+
+out_fail:
+	dec_count(inode);
+	iput(inode);
+	goto out;
 }
 
-static int sysv_mkdir(struct inode * dir, struct dentry *dentry, int mode)
+static int sysv_link(struct dentry * old_dentry, struct inode * dir, 
+	struct dentry * dentry)
 {
-	int error;
-	struct inode * inode;
-	struct buffer_head * bh, *dir_block;
-	struct sysv_dir_entry * de;
+	struct inode *inode = old_dentry->d_inode;
 
-	bh = sysv_find_entry(dir, dentry->d_name.name,
-                              dentry->d_name.len, &de);
-	if (bh) {
-		brelse(bh);
-		return -EEXIST;
-	}
-	if (dir->i_nlink >= dir->i_sb->sv_link_max) 
+	if (S_ISDIR(inode->i_mode))
+		return -EPERM;
+
+	if (inode->i_nlink >= inode->i_sb->sv_link_max)
 		return -EMLINK;
-	inode = sysv_new_inode(dir);
-	if (!inode)
-		return -ENOSPC;
-	inode->i_op = &sysv_dir_inode_operations;
-	inode->i_fop = &sysv_dir_operations;
-	inode->i_size = 2 * SYSV_DIRSIZE;
-	dir_block = sysv_file_bread(inode,0,1);
-	if (!dir_block) {
-		inode->i_nlink--;
-		mark_inode_dirty(inode);
-		iput(inode);
-		return -ENOSPC;
-	}
-	de = (struct sysv_dir_entry *) (dir_block->b_data + 0*SYSV_DIRSIZE);
-	de->inode = inode->i_ino;
-	strcpy(de->name,"."); /* rest of de->name is zero, see sysv_new_block */
-	de = (struct sysv_dir_entry *) (dir_block->b_data + 1*SYSV_DIRSIZE);
-	de->inode = dir->i_ino;
-	strcpy(de->name,".."); /* rest of de->name is zero, see sysv_new_block */
-	inode->i_nlink = 2;
-	mark_buffer_dirty(dir_block);
-	brelse(dir_block);
-	inode->i_mode = S_IFDIR | mode;
-	if (dir->i_mode & S_ISGID)
-		inode->i_mode |= S_ISGID;
-	mark_inode_dirty(inode);
-	error = sysv_add_entry(dir, dentry->d_name.name,
-                               dentry->d_name.len, &bh, &de);
- 	if (error) {
-		inode->i_nlink=0;
-		iput(inode);
-		return error;
-	}
-	de->inode = inode->i_ino;
-	mark_buffer_dirty(bh);
-	dir->i_nlink++;
-	mark_inode_dirty(dir);
-	brelse(bh);
-        d_instantiate(dentry, inode);
- 	return 0;
-}
 
-/*
- * routine to check that the specified directory is empty (for rmdir)
- */
-static int empty_dir(struct inode * inode)
-{
-	struct super_block * sb;
-	unsigned long pos, block, offset; /* pos = block * block_size + offset */
-	struct buffer_head * bh;
-	struct sysv_dir_entry * de;
+	inode->i_ctime = CURRENT_TIME;
+	inc_count(inode);
+	atomic_inc(&inode->i_count);
 
-	block = 0;
-	bh = NULL;
-	pos = offset = 2*SYSV_DIRSIZE;
-	if ((unsigned long)(inode->i_size) % SYSV_DIRSIZE)
-		goto bad_dir;
-	if (inode->i_size < pos)
-		goto bad_dir;
-	bh = sysv_file_bread(inode, 0, 0);
-	if (!bh)
-		goto bad_dir;
-	de = (struct sysv_dir_entry *) (bh->b_data + 0*SYSV_DIRSIZE);
-	if (!de->inode || strcmp(de->name,"."))
-		goto bad_dir;
-	de = (struct sysv_dir_entry *) (bh->b_data + 1*SYSV_DIRSIZE);
-	if (!de->inode || strcmp(de->name,".."))
-		goto bad_dir;
-	sb = inode->i_sb;
-	while (pos < inode->i_size) {
-		if (!bh) {
-			bh = sysv_file_bread(inode, block, 0);
-			if (!bh) {
-				/* offset = 0; */ block++;
-				pos += sb->sv_block_size;
-				continue;
-			}
-		}
-		de = (struct sysv_dir_entry *) (bh->b_data + offset);
-		pos += SYSV_DIRSIZE;
-		offset += SYSV_DIRSIZE;
-		if (de->inode) {
-			brelse(bh);
-			return 0;
-		}
-		if (offset < sb->sv_block_size)
-			continue;
-		brelse(bh);
-		bh = NULL;
-		offset = 0; block++;
-	}
-	brelse(bh);
-	return 1;
-bad_dir:
-	brelse(bh);
-	printk("Bad directory on device %s\n",
-	       kdevname(inode->i_dev));
-	return 1;
+	return add_nondir(dentry, inode);
 }
 
-static int sysv_rmdir(struct inode * dir, struct dentry * dentry)
+static int sysv_mkdir(struct inode * dir, struct dentry *dentry, int mode)
 {
-	int retval;
 	struct inode * inode;
-	struct buffer_head * bh;
-	struct sysv_dir_entry * de;
+	int err = -EMLINK;
 
-	inode = dentry->d_inode;
-	bh = sysv_find_entry(dir, dentry->d_name.name, dentry->d_name.len, &de);
-	retval = -ENOENT;
-	if (!bh || de->inode != inode->i_ino)
-		goto end_rmdir;
-
-	if (!empty_dir(inode)) {
-		retval = -ENOTEMPTY;
-		goto end_rmdir;
-	}
-	if (inode->i_nlink != 2)
-		printk("empty directory has nlink!=2 (%d)\n", inode->i_nlink);
-	de->inode = 0;
-	mark_buffer_dirty(bh);
-	inode->i_nlink=0;
-	dir->i_nlink--;
-	inode->i_ctime = dir->i_ctime = dir->i_mtime = CURRENT_TIME;
-	mark_inode_dirty(inode);
-	mark_inode_dirty(dir);
-	retval = 0;
-end_rmdir:
-	brelse(bh);
-	return retval;
-}
+	if (dir->i_nlink >= dir->i_sb->sv_link_max) 
+		goto out;
 
-static int sysv_unlink(struct inode * dir, struct dentry * dentry)
-{
-	int retval;
-	struct inode * inode;
-	struct buffer_head * bh;
-	struct sysv_dir_entry * de;
+	inc_count(dir);
 
-	retval = -ENOENT;
-	inode = dentry->d_inode;
-	bh = sysv_find_entry(dir, dentry->d_name.name, dentry->d_name.len, &de);
-	if (!bh || de->inode != inode->i_ino)
-		goto end_unlink;
-	if (!inode->i_nlink) {
-		printk("Deleting nonexistent file (%s:%lu), %d\n",
-		        kdevname(inode->i_dev), inode->i_ino, inode->i_nlink);
-		inode->i_nlink=1;
-	}
-	de->inode = 0;
-	mark_buffer_dirty(bh);
-	dir->i_ctime = dir->i_mtime = CURRENT_TIME;
-	mark_inode_dirty(dir);
-	inode->i_nlink--;
-	inode->i_ctime = dir->i_ctime;
-	mark_inode_dirty(inode);
-	retval = 0;
-end_unlink:
-	brelse(bh);
-	return retval;
-}
+	if (dir->i_mode & S_ISGID)
+		mode |= S_ISGID;
 
-static int sysv_symlink(struct inode * dir, struct dentry * dentry, 
-		 const char * symname)
-{
-	struct inode * inode;
-	struct sysv_dir_entry * de;
-	struct buffer_head * bh;
-	int err;
-	int l;
-
-	err = -ENAMETOOLONG;
-	l = strlen(symname)+1;
-	if (l > dir->i_sb->sv_block_size_1)
-		goto out;
 	err = -ENOSPC;
-	if (!(inode = sysv_new_inode(dir)))
-		goto out;
+	inode = sysv_new_inode(dir, S_IFDIR|mode);
+	if (!inode)
+		goto out_dir;
+	sysv_set_inode(inode, 0);
 
-	inode->i_mode = S_IFLNK | 0777;
-	inode->i_op = &sysv_symlink_inode_operations;
-	inode->i_mapping->a_ops = &sysv_aops;
-	err = block_symlink(inode, symname, l);
+	inc_count(inode);
+
+	err = sysv_make_empty(inode, dir);
 	if (err)
-		goto out_no_entry;
-	mark_inode_dirty(inode);
-	err = sysv_add_entry(dir, dentry->d_name.name,
-                           dentry->d_name.len, &bh, &de);
+		goto out_fail;
+
+	err = sysv_add_link(dentry, inode);
 	if (err)
-		goto out_no_entry;
-	de->inode = inode->i_ino;
-	mark_buffer_dirty(bh);
-	brelse(bh);
+		goto out_fail;
+
         d_instantiate(dentry, inode);
 out:
 	return err;
-out_no_entry:
-	inode->i_nlink--;
-	mark_inode_dirty(inode);
+
+out_fail:
+	dec_count(inode);
+	dec_count(inode);
 	iput(inode);
+out_dir:
+	dec_count(dir);
 	goto out;
 }
 
-static int sysv_link(struct dentry * old_dentry, struct inode * dir, 
-	      struct dentry * dentry)
+static int sysv_unlink(struct inode * dir, struct dentry * dentry)
 {
-	struct inode *oldinode = old_dentry->d_inode;
-	int error;
+	struct inode * inode = dentry->d_inode;
+	struct page * page;
 	struct sysv_dir_entry * de;
-	struct buffer_head * bh;
+	int err = -ENOENT;
 
-	if (S_ISDIR(oldinode->i_mode)) {
-		return -EPERM;
-	}
-	if (oldinode->i_nlink >= oldinode->i_sb->sv_link_max) {
-		return -EMLINK;
-	}
-	bh = sysv_find_entry(dir, dentry->d_name.name,
-                             dentry->d_name.len, &de);
-	if (bh) {
-		brelse(bh);
-		return -EEXIST;
-	}
-	error = sysv_add_entry(dir, dentry->d_name.name,
-                               dentry->d_name.len, &bh, &de);
-	if (error) {
-		brelse(bh);
-		return error;
-	}
-	de->inode = oldinode->i_ino;
-	mark_buffer_dirty(bh);
-	brelse(bh);
-	oldinode->i_nlink++;
-	oldinode->i_ctime = CURRENT_TIME;
-	mark_inode_dirty(oldinode);
-	atomic_inc(&oldinode->i_count);
-        d_instantiate(dentry, oldinode);
-	return 0;
+	de = sysv_find_entry(dentry, &page);
+	if (!de)
+		goto out;
+
+	err = sysv_delete_entry (de, page);
+	if (err)
+		goto out;
+
+	inode->i_ctime = dir->i_ctime;
+	dec_count(inode);
+out:
+	return err;
 }
 
-#define PARENT_INO(buffer) \
-(((struct sysv_dir_entry *) ((buffer) + 1*SYSV_DIRSIZE))->inode)
+static int sysv_rmdir(struct inode * dir, struct dentry * dentry)
+{
+	struct inode *inode = dentry->d_inode;
+	int err = -ENOTEMPTY;
+
+	if (sysv_empty_dir(inode)) {
+		err = sysv_unlink(dir, dentry);
+		if (!err) {
+			dec_count(inode);
+			dec_count(dir);
+		}
+	}
+	return err;
+}
 
 /*
  * Anybody can rename anything with this: the permission checks are left to the
@@ -522,83 +231,78 @@
 static int sysv_rename(struct inode * old_dir, struct dentry * old_dentry,
 		  struct inode * new_dir, struct dentry * new_dentry)
 {
-	struct inode * old_inode, * new_inode;
-	struct buffer_head * old_bh, * new_bh, * dir_bh;
-	struct sysv_dir_entry * old_de, * new_de;
-	int retval;
-
-	old_inode = old_dentry->d_inode;
-	new_inode = new_dentry->d_inode;
-	new_bh = dir_bh = NULL;
-	old_bh = sysv_find_entry(old_dir, old_dentry->d_name.name,
-				old_dentry->d_name.len, &old_de);
-	retval = -ENOENT;
-	if (!old_bh || old_de->inode != old_inode->i_ino)
-		goto end_rename;
-	retval = -EPERM;
-	new_bh = sysv_find_entry(new_dir, new_dentry->d_name.name,
-				new_dentry->d_name.len, &new_de);
-	if (new_bh) {
-		if (!new_inode) {
-			brelse(new_bh);
-			new_bh = NULL;
-		}
-	}
+	struct inode * old_inode = old_dentry->d_inode;
+	struct inode * new_inode = new_dentry->d_inode;
+	struct page * dir_page = NULL;
+	struct sysv_dir_entry * dir_de = NULL;
+	struct page * old_page;
+	struct sysv_dir_entry * old_de;
+	int err = -ENOENT;
+
+	old_de = sysv_find_entry(old_dentry, &old_page);
+	if (!old_de)
+		goto out;
+
 	if (S_ISDIR(old_inode->i_mode)) {
-		if (new_inode) {
-			retval = -ENOTEMPTY;
-			if (!empty_dir(new_inode))
-				goto end_rename;
-		}
-		retval = -EIO;
-		dir_bh = sysv_file_bread(old_inode, 0, 0);
-		if (!dir_bh)
-			goto end_rename;
-		if (PARENT_INO(dir_bh->b_data) != old_dir->i_ino)
-			goto end_rename;
-		retval = -EMLINK;
-		if (!new_inode && new_dir != old_dir &&
-				new_dir->i_nlink >= new_dir->i_sb->sv_link_max)
-			goto end_rename;
+		err = -EIO;
+		dir_de = sysv_dotdot(old_inode, &dir_page);
+		if (!dir_de)
+			goto out_old;
 	}
-	if (!new_bh) {
-		retval = sysv_add_entry(new_dir, new_dentry->d_name.name,
-					new_dentry->d_name.len, &new_bh, &new_de);
-		if (retval)
-			goto end_rename;
-	}
-	new_de->inode = old_inode->i_ino;
-	old_de->inode = 0;
-	old_dir->i_ctime = old_dir->i_mtime = CURRENT_TIME;
-	mark_inode_dirty(old_dir);
-	new_dir->i_ctime = new_dir->i_mtime = CURRENT_TIME;
-	mark_inode_dirty(new_dir);
+
 	if (new_inode) {
-		new_inode->i_nlink--;
+		struct page * new_page;
+		struct sysv_dir_entry * new_de;
+
+		err = -ENOTEMPTY;
+		if (dir_de && !sysv_empty_dir(new_inode))
+			goto out_dir;
+
+		err = -ENOENT;
+		new_de = sysv_find_entry(new_dentry, &new_page);
+		if (!new_de)
+			goto out_dir;
+		inc_count(old_inode);
+		sysv_set_link(new_de, new_page, old_inode);
 		new_inode->i_ctime = CURRENT_TIME;
-		mark_inode_dirty(new_inode);
-	}
-	mark_buffer_dirty(old_bh);
-	mark_buffer_dirty(new_bh);
-	if (dir_bh) {
-		PARENT_INO(dir_bh->b_data) = new_dir->i_ino;
-		mark_buffer_dirty(dir_bh);
-		old_dir->i_nlink--;
-		mark_inode_dirty(old_dir);
-		if (new_inode) {
+		if (dir_de)
 			new_inode->i_nlink--;
-			mark_inode_dirty(new_inode);
-		} else {
-			new_dir->i_nlink++;
-			mark_inode_dirty(new_dir);
+		dec_count(new_inode);
+	} else {
+		if (dir_de) {
+			err = -EMLINK;
+			if (new_dir->i_nlink >= new_dir->i_sb->sv_link_max)
+				goto out_dir;
+		}
+		inc_count(old_inode);
+		err = sysv_add_link(new_dentry, old_inode);
+		if (err) {
+			dec_count(old_inode);
+			goto out_dir;
 		}
+		if (dir_de)
+			inc_count(new_dir);
+	}
+
+	sysv_delete_entry(old_de, old_page);
+	dec_count(old_inode);
+
+	if (dir_de) {
+		sysv_set_link(dir_de, dir_page, new_dir);
+		dec_count(old_dir);
 	}
-	retval = 0;
-end_rename:
-	brelse(dir_bh);
-	brelse(old_bh);
-	brelse(new_bh);
-	return retval;
+	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;
 }
 
 /*