patch-2.1.21 linux/fs/xiafs/namei.c

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diff -u --recursive --new-file v2.1.20/linux/fs/xiafs/namei.c linux/fs/xiafs/namei.c
@@ -1,854 +0,0 @@
-/*
- *  Linux/fs/xiafs/namei.c
- *
- *  Copyright (C) Q. Frank Xia, 1993.
- *  
- *  Based on Linus' minix/namei.c
- *  Copyright (C) Linus Torvalds, 1991, 1992.
- * 
- *  This software may be redistributed per Linux Copyright.
- */
-
-#include <linux/sched.h>
-#include <linux/xia_fs.h>
-#include <linux/kernel.h>
-#include <linux/string.h>
-#include <linux/stat.h>
-#include <linux/fcntl.h>
-#include <linux/errno.h>
-
-#include <asm/uaccess.h>
-
-#include "xiafs_mac.h"
-
-#define RNDUP4(x)	((3+(u_long)(x)) & ~3)
-/*
- * ok, we cannot use strncmp, as the name is not in our data space.
- * Thus we'll have to use xiafs_match. No big problem. Match also makes
- * some sanity tests.
- *
- * NOTE! unlike strncmp, xiafs_match returns 1 for success, 0 for failure.
- */
-static int xiafs_match(int len, const char * name, struct xiafs_direct * dep)
-{
-    int i;
-
-    if (!dep || !dep->d_ino || len > _XIAFS_NAME_LEN)
-        return 0;
-    /* "" means "." ---> so paths like "/usr/lib//libc.a" work */
-    if (!len && (dep->d_name[0]=='.') && (dep->d_name[1]=='\0'))
-        return 1;
-    if (len != dep->d_name_len)
-        return 0;
-    for (i=0; i < len; i++)
-        if (*name++ != dep->d_name[i])
-	    return 0;
-    return 1;
-}
-
-/*
- *	xiafs_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 * 
-xiafs_find_entry(struct inode * inode, const char * name, int namelen, 
-	       struct xiafs_direct ** res_dir, struct xiafs_direct ** res_pre)
-{
-    int i, zones, pos;
-    struct buffer_head * bh;
-    struct xiafs_direct * dep, * dep_pre;
-
-    *res_dir = NULL;
-    if (!inode)
-        return NULL;
-    if (namelen > _XIAFS_NAME_LEN)
-        return NULL;
-
-    if (inode->i_size & (XIAFS_ZSIZE(inode->i_sb) - 1)) {
-        printk("XIA-FS: bad dir size (%s %d)\n", WHERE_ERR);
-	return NULL;
-    }
-    zones=inode->i_size >> XIAFS_ZSIZE_BITS(inode->i_sb);
-    for (i=0; i < zones; i++ ) {
-        bh = xiafs_bread(inode, i, 0);
-	if (!bh)
-	    continue;
-	dep_pre=dep=(struct xiafs_direct *)bh->b_data;
-	if (!i && (dep->d_rec_len != 12 || !dep->d_ino || 
-		   dep->d_name_len != 1 || strcmp(dep->d_name, "."))) {
-	    printk("XIA-FS: bad directory (%s %d)\n", WHERE_ERR);
-	    brelse(bh);
-	    return NULL;
-	}
-	pos = 0;
-	while ( pos < XIAFS_ZSIZE(inode->i_sb) ) {
-	    if (dep->d_ino > inode->i_sb->u.xiafs_sb.s_ninodes ||
-		dep->d_rec_len < 12 || 
-		dep->d_rec_len+(char *)dep > bh->b_data+XIAFS_ZSIZE(inode->i_sb) ||
-		dep->d_name_len + 8 > dep->d_rec_len || dep->d_name_len <= 0 ||
-		dep->d_name[dep->d_name_len] ) {
-	        brelse(bh);
-		return NULL;
-	    }
-	    if (xiafs_match(namelen, name, dep)) {
-	        *res_dir=dep;
-		if (res_pre) 
-		    *res_pre=dep_pre;
-		return bh;
-	    }
-	    pos += dep->d_rec_len;
-	    dep_pre=dep;
-	    dep=(struct xiafs_direct *)(bh->b_data + pos);
-	}
-	brelse(bh);
-	if (pos > XIAFS_ZSIZE(inode->i_sb)) {
-	    printk("XIA-FS: bad directory (%s %d)\n", WHERE_ERR);
-	    return NULL;
-	}
-    }
-    return NULL;
-}
-
-int xiafs_lookup(struct inode * dir, const char * name, int len,
-	       struct inode ** result)
-{
-    int ino;
-    struct xiafs_direct * dep;
-    struct buffer_head * bh;
-
-    *result = NULL;
-    if (!dir)
-        return -ENOENT;
-    if (!S_ISDIR(dir->i_mode)) {
-        iput(dir);
-	return -ENOENT;
-    }
-    if (!(bh = xiafs_find_entry(dir, name, len, &dep, NULL))) {
-        iput(dir);
-	return -ENOENT;
-    }
-    ino = dep->d_ino;
-    brelse(bh);
-    if (!(*result = iget(dir->i_sb, ino))) {
-        iput(dir);
-	return -EACCES;
-    }
-    iput(dir);
-    return 0;
-}
-
-/*
- *	xiafs_add_entry()
- *
- * adds a file entry to the specified directory, using the same
- * semantics as xiafs_find_entry(). It returns NULL if it failed.
- *
- * 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 struct buffer_head * xiafs_add_entry(struct inode * dir,
-	const char * name, int namelen, struct xiafs_direct ** res_dir, 
-	struct xiafs_direct ** res_pre)
-{
-    int i, pos, offset;
-    struct buffer_head * bh;
-    struct xiafs_direct * de, * de_pre;
-
-    *res_dir = NULL;
-    if (!dir || !namelen || namelen > _XIAFS_NAME_LEN)
-        return NULL;
-
-    if (dir->i_size & (XIAFS_ZSIZE(dir->i_sb) - 1)) {
-        printk("XIA-FS: bad dir size (%s %d)\n", WHERE_ERR);
-	return NULL;
-    }
-    pos=0;
-    for ( ; ; ) {
-        bh =  xiafs_bread(dir, pos >> XIAFS_ZSIZE_BITS(dir->i_sb), pos ? 1:0);
-	if (!bh)
-	    return NULL;
-	de_pre=de=(struct xiafs_direct *)bh->b_data;
-	if (!pos) {
-	    if (de->d_rec_len != 12 || !de->d_ino || de->d_name_len != 1 ||
-		strcmp(de->d_name, ".")) {
-	        printk("XIA-FS: bad directory (%s %d)\n", WHERE_ERR);
-		brelse(bh);
-		return NULL;
-	    }
-	    offset = 12;
-	    de_pre=de=(struct xiafs_direct *)(bh->b_data+12);
-	} else
-	    offset = 0;
-	while (offset < XIAFS_ZSIZE(dir->i_sb)) {
-	    if (pos >= dir->i_size) {
-	        de->d_ino=0;
-		de->d_name_len=0;
-		de->d_name[0]=0;
-		de->d_rec_len=XIAFS_ZSIZE(dir->i_sb);
-		dir->i_size += XIAFS_ZSIZE(dir->i_sb);
-		dir->i_dirt = 1;
-	    } else {
-	        if (de->d_ino > dir->i_sb->u.xiafs_sb.s_ninodes ||
-		    de->d_rec_len < 12 || 
-		    (char *)de+de->d_rec_len > bh->b_data+XIAFS_ZSIZE(dir->i_sb) ||
-		    de->d_name_len + 8 > de->d_rec_len ||
-		    de->d_name[de->d_name_len]) {
-		    printk("XIA-FS: bad directory entry (%s %d)\n", WHERE_ERR);
-		    brelse(bh);
-		    return NULL;
-		}
-		if (de->d_ino &&
-		    RNDUP4(de->d_name_len)+RNDUP4(namelen)+16<=de->d_rec_len) {
-		    i=RNDUP4(de->d_name_len)+8;
-		    de_pre=de;
-		    de=(struct xiafs_direct *)(i+(u_char *)de_pre);
-		    de->d_ino=0;
-		    de->d_rec_len=de_pre->d_rec_len-i;
-		    de_pre->d_rec_len=i;
-		}
-	    }
-	    if (!de->d_ino && RNDUP4(namelen)+8 <= de->d_rec_len) {
-		/*
-		 * XXX all times should be set by caller upon successful
-		 * completion.
-		 */
-	        dir->i_ctime = dir->i_mtime = CURRENT_TIME;
-		dir->i_dirt = 1;
-		memcpy(de->d_name, name, namelen);
-		de->d_name[namelen]=0;
-		de->d_name_len=namelen;
-		mark_buffer_dirty(bh, 1);
-		*res_dir = de;
-		if (res_pre)
-		    *res_pre = de_pre;
-		return bh;
-	    }
-	    offset+=de->d_rec_len;
-	    de_pre=de;
-	    de=(struct xiafs_direct *)(bh->b_data+offset);
-	}
-	brelse(bh);
-	if (offset > XIAFS_ZSIZE(dir->i_sb)) {
-	    printk("XIA-FS: bad directory (%s %d)\n", WHERE_ERR);
-	    return NULL;
-	}
-	pos+=XIAFS_ZSIZE(dir->i_sb);
-    }
-    return NULL;
-}
-
-int xiafs_create(struct inode * dir, const char * name, int len, int mode,
-	struct inode ** result)
-{
-    struct inode * inode;
-    struct buffer_head * bh;
-    struct xiafs_direct * de;
-
-    *result = NULL;
-    if (!dir)
-        return -ENOENT;
-    inode = xiafs_new_inode(dir);
-    if (!inode) {
-        iput(dir);
-	return -ENOSPC;
-    }
-    inode->i_op = &xiafs_file_inode_operations;
-    inode->i_mode = mode;
-    inode->i_dirt = 1;
-    bh = xiafs_add_entry(dir, name, len, &de, NULL);
-    if (!bh) {
-        inode->i_nlink--;
-	inode->i_dirt = 1;
-	iput(inode);
-	iput(dir);
-	return -ENOSPC;
-    }
-    de->d_ino = inode->i_ino;
-    mark_buffer_dirty(bh, 1);
-    brelse(bh);
-    iput(dir);
-    *result = inode;
-    return 0;
-}
-
-int xiafs_mknod(struct inode *dir, const char *name, int len, int mode, int rdev)
-{
-    struct inode * inode;
-    struct buffer_head * bh;
-    struct xiafs_direct * de;
-
-    if (!dir)
-        return -ENOENT;
-    bh = xiafs_find_entry(dir,name,len,&de, NULL);
-    if (bh) {
-        brelse(bh);
-	iput(dir);
-	return -EEXIST;
-    }
-    inode = xiafs_new_inode(dir);
-    if (!inode) {
-        iput(dir);
-	return -ENOSPC;
-    }
-    inode->i_uid = current->fsuid;
-    inode->i_mode = mode;
-    inode->i_op = NULL;
-    if (S_ISREG(inode->i_mode))
-        inode->i_op = &xiafs_file_inode_operations;
-    else if (S_ISDIR(inode->i_mode)) {
-        inode->i_op = &xiafs_dir_inode_operations;
-	if (dir->i_mode & S_ISGID)
-	    inode->i_mode |= S_ISGID;
-    }
-    else if (S_ISLNK(inode->i_mode))
-        inode->i_op = &xiafs_symlink_inode_operations;
-    else if (S_ISCHR(inode->i_mode))
-        inode->i_op = &chrdev_inode_operations;
-    else if (S_ISBLK(inode->i_mode))
-        inode->i_op = &blkdev_inode_operations;
-    else if (S_ISFIFO(inode->i_mode))
-    	init_fifo(inode);
-    if (S_ISBLK(mode) || S_ISCHR(mode))
-        inode->i_rdev = to_kdev_t(rdev);
-    inode->i_atime = inode->i_ctime = inode->i_atime = CURRENT_TIME;
-    inode->i_dirt = 1;
-    bh = xiafs_add_entry(dir, name, len, &de, NULL);
-    if (!bh) {
-        inode->i_nlink--;
-	inode->i_dirt = 1;
-	iput(inode);
-	iput(dir);
-	return -ENOSPC;
-    }
-    de->d_ino = inode->i_ino;
-    mark_buffer_dirty(bh, 1);
-    brelse(bh);
-    iput(dir);
-    iput(inode);
-    return 0;
-}
-
-int xiafs_mkdir(struct inode * dir, const char * name, int len, int mode)
-{
-    struct inode * inode;
-    struct buffer_head * bh, *dir_block;
-    struct xiafs_direct * de;
-	
-    bh = xiafs_find_entry(dir,name,len,&de, NULL);
-    if (bh) {
-        brelse(bh);
-	iput(dir);
-	return -EEXIST;
-    }
-    if (dir->i_nlink > 64000) {
-        iput(dir);
-        return -EMLINK;
-    }
-    inode = xiafs_new_inode(dir);
-    if (!inode) {
-        iput(dir);
-	return -ENOSPC;
-    }
-    inode->i_op = &xiafs_dir_inode_operations;
-    inode->i_size = XIAFS_ZSIZE(dir->i_sb);
-    inode->i_atime = inode->i_ctime = inode->i_mtime = CURRENT_TIME;
-    inode->i_dirt = 1;
-    dir_block = xiafs_bread(inode,0,1);
-    if (!dir_block) {
-        iput(dir);
-	inode->i_nlink--;
-	inode->i_dirt = 1;
-	iput(inode);
-	return -ENOSPC;
-    }
-    de = (struct xiafs_direct *) dir_block->b_data;
-    de->d_ino=inode->i_ino;
-    strcpy(de->d_name,".");
-    de->d_name_len=1;
-    de->d_rec_len=12;
-    de =(struct xiafs_direct *)(12 + dir_block->b_data);
-    de->d_ino = dir->i_ino;
-    strcpy(de->d_name,"..");
-    de->d_name_len=2;
-    de->d_rec_len=XIAFS_ZSIZE(dir->i_sb)-12;
-    inode->i_nlink = 2;
-    mark_buffer_dirty(dir_block, 1);
-    brelse(dir_block);
-    inode->i_mode = S_IFDIR | (mode & S_IRWXUGO & ~current->fs->umask);
-    if (dir->i_mode & S_ISGID)
-        inode->i_mode |= S_ISGID;
-    inode->i_dirt = 1;
-    bh = xiafs_add_entry(dir, name, len, &de, NULL);
-    if (!bh) {
-        iput(dir);
-	inode->i_nlink=0;
-	iput(inode);
-	return -ENOSPC;
-    }
-    de->d_ino = inode->i_ino;
-    mark_buffer_dirty(bh, 1);
-    dir->i_nlink++;
-    dir->i_dirt = 1;
-    iput(dir);
-    iput(inode);
-    brelse(bh);
-    return 0;
-}
-
-/*
- * routine to check that the specified directory is empty (for rmdir)
- */
-static int empty_dir(struct inode * inode)
-{
-    int i, zones, offset;
-    struct buffer_head * bh;
-    struct xiafs_direct * de;
-
-    if (inode->i_size & (XIAFS_ZSIZE(inode->i_sb)-1) ) {
-        printk("XIA-FS: bad directory (%s %d)\n", WHERE_ERR);
-	return 1;
-    }
-
-    zones=inode->i_size >> XIAFS_ZSIZE_BITS(inode->i_sb);
-    for (i=0; i < zones; i++) {
-        bh =  xiafs_bread(inode, i, 0);
-	if (!i) {
-	    if (!bh) {
-	        printk("XIA-FS: bad directory (%s %d)\n", WHERE_ERR);
-		return 1;
-	    }
-	    de=(struct xiafs_direct *)bh->b_data;
-	    if (de->d_ino != inode->i_ino || strcmp(".", de->d_name) ||
-		    de->d_rec_len != 12 ) {
-	        printk("XIA-FS: bad directory (%s %d)\n", WHERE_ERR);
-		brelse(bh);
-		return 1;	 
-	    }
-	    de=(struct xiafs_direct *)(12 + bh->b_data);
-	    if (!de->d_ino || strcmp("..", de->d_name)) {
-	    	printk("XIA-FS: bad directory (%s %d)\n", WHERE_ERR);
-		brelse(bh);
-		return 1;
-	    }
-	    offset=de->d_rec_len+12;
-	}
-	else
-	    offset = 0;
-	if (!bh)
-	    continue;
-	while (offset < XIAFS_ZSIZE(inode->i_sb)) {
-	    de=(struct xiafs_direct *)(bh->b_data+offset);
-	    if (de->d_ino > inode->i_sb->u.xiafs_sb.s_ninodes ||
-		de->d_rec_len < 12 || 
-		(char *)de+de->d_rec_len > bh->b_data+XIAFS_ZSIZE(inode->i_sb) ||
-		de->d_name_len + 8 > de->d_rec_len ||
-		de->d_name[de->d_name_len]) {
-	        printk("XIA-FS: bad directory (%s %d)\n", WHERE_ERR);
-		brelse(bh);
-		return 1;
-	    }
-	    if (de->d_ino) {
-	        brelse(bh);
-		return 0;
-	    }
-	    offset+=de->d_rec_len;
-	}
-	brelse(bh);
-    }
-    return 1;
-}
-
-static void xiafs_rm_entry(struct xiafs_direct *de, struct xiafs_direct * de_pre)
-{
-    if (de==de_pre) {
-        de->d_ino=0;
-	return;
-    }
-    while (de_pre->d_rec_len+(u_char *)de_pre < (u_char *)de) {
-        if (de_pre->d_rec_len < 12) {
-	    printk("XIA-FS: bad directory entry (%s %d)\n", WHERE_ERR);
-	    return;
-	}
-        de_pre=(struct xiafs_direct *)(de_pre->d_rec_len+(u_char *)de_pre);
-    }
-    if (de_pre->d_rec_len+(u_char *)de_pre > (u_char *)de) {
-        printk("XIA-FS: bad directory entry (%s %d)\n", WHERE_ERR);
-	return;
-    }
-    de_pre->d_rec_len+=de->d_rec_len;
-}
-
-int xiafs_rmdir(struct inode * dir, const char * name, int len)
-{
-    int retval;
-    struct inode * inode;
-    struct buffer_head * bh;
-    struct xiafs_direct * de, * de_pre;
-
-    inode = NULL;
-    bh = xiafs_find_entry(dir, name, len, &de, &de_pre);
-    retval = -ENOENT;
-    if (!bh)
-        goto end_rmdir;
-    retval = -EPERM;
-    if (!(inode = iget(dir->i_sb, de->d_ino)))
-        goto end_rmdir;
-    if ((dir->i_mode & S_ISVTX) && !fsuser() &&
-            current->fsuid != inode->i_uid &&
-            current->fsuid != dir->i_uid)
-        goto end_rmdir;
-    if (inode->i_dev != dir->i_dev)
-        goto end_rmdir;
-    if (inode == dir)	/* we may not delete ".", but "../dir" is ok */
-        goto end_rmdir;
-    if (!S_ISDIR(inode->i_mode)) {
-        retval = -ENOTDIR;
-	goto end_rmdir;
-    }
-    if (!empty_dir(inode)) {
-        retval = -ENOTEMPTY;
-	goto end_rmdir;
-    }
-    if (inode->i_count > 1) {
-        retval = -EBUSY;
-	goto end_rmdir;
-    }
-    if (inode->i_nlink != 2)
-        printk("XIA-FS: empty directory has nlink!=2 (%s %d)\n", WHERE_ERR);
-    xiafs_rm_entry(de, de_pre);
-    mark_buffer_dirty(bh, 1);
-    inode->i_nlink=0;
-    inode->i_dirt=1;
-    dir->i_nlink--;
-    inode->i_ctime = dir->i_ctime = dir->i_mtime = CURRENT_TIME;
-    dir->i_dirt=1;
-    retval = 0;
-end_rmdir:
-    iput(dir);
-    iput(inode);
-    brelse(bh);
-    return retval;
-}
-
-int xiafs_unlink(struct inode * dir, const char * name, int len)
-{
-    int retval;
-    struct inode * inode;
-    struct buffer_head * bh;
-    struct xiafs_direct * de, * de_pre;
-
-repeat:
-    retval = -ENOENT;
-    inode = NULL;
-    bh = xiafs_find_entry(dir, name, len, &de, &de_pre);
-    if (!bh)
-        goto end_unlink;
-    if (!(inode = iget(dir->i_sb, de->d_ino)))
-        goto end_unlink;
-    retval = -EPERM;
-    if (S_ISDIR(inode->i_mode))
-        goto end_unlink;
-    if (de->d_ino != inode->i_ino) {
-        iput(inode);
-	brelse(bh);
-	current->counter = 0;
-	schedule();
-	goto repeat;
-    }
-    if ((dir->i_mode & S_ISVTX) && !fsuser() &&
-	    current->fsuid != inode->i_uid &&
-	    current->fsuid != dir->i_uid)
-        goto end_unlink;
-    if (!inode->i_nlink) {
-        printk("XIA-FS: Deleting nonexistent file (%s %d)\n", WHERE_ERR);
-	inode->i_nlink=1;
-    }
-    xiafs_rm_entry(de, de_pre);
-    mark_buffer_dirty(bh, 1);
-    inode->i_ctime = dir->i_ctime = dir->i_mtime = CURRENT_TIME;
-    dir->i_dirt = 1;
-    inode->i_nlink--;
-    inode->i_dirt = 1;
-    retval = 0;
-end_unlink:
-    brelse(bh);
-    iput(inode);
-    iput(dir);
-    return retval;
-}
-
-int xiafs_symlink(struct inode * dir, const char * name, 
-		int len, const char * symname)
-{
-    struct xiafs_direct * de;
-    struct inode * inode = NULL;
-    struct buffer_head * bh = NULL, * name_block = NULL;
-    int i;
-    char c;
-
-    bh = xiafs_find_entry(dir,name,len, &de, NULL);
-    if (bh) {
-	brelse(bh);
-	iput(dir);
-	return -EEXIST;
-    }
-    if (!(inode = xiafs_new_inode(dir))) {
-        iput(dir);
-	return -ENOSPC;
-    }
-    inode->i_mode = S_IFLNK | S_IRWXUGO;
-    inode->i_op = &xiafs_symlink_inode_operations;
-    name_block = xiafs_bread(inode,0,1);
-    if (!name_block) {
-        iput(dir);
-	inode->i_nlink--;
-	inode->i_dirt = 1;
-	iput(inode);
-	return -ENOSPC;
-    }
-    for (i = 0; i < BLOCK_SIZE-1 && (c=*symname++); i++)
-        name_block->b_data[i] = c;
-    name_block->b_data[i] = 0;
-    mark_buffer_dirty(name_block, 1);
-    brelse(name_block);
-    inode->i_size = i;
-    inode->i_dirt = 1;
-    bh = xiafs_add_entry(dir, name, len, &de, NULL);
-    if (!bh) {
-        inode->i_nlink--;
-	inode->i_dirt = 1;
-	iput(inode);
-	iput(dir);
-	return -ENOSPC;
-    }
-    de->d_ino = inode->i_ino;
-    mark_buffer_dirty(bh, 1);
-    brelse(bh);
-    iput(dir);
-    iput(inode);
-    return 0;
-}
-
-int xiafs_link(struct inode * oldinode, struct inode * dir, 
-	     const char * name, int len)
-{
-    struct xiafs_direct * de;
-    struct buffer_head * bh;
-
-    if (S_ISDIR(oldinode->i_mode)) {
-        iput(oldinode);
-	iput(dir);
-	return -EPERM;
-    }
-    if (oldinode->i_nlink > 64000) {
-        iput(oldinode);
-	iput(dir);
-	return -EMLINK;
-    }
-    bh = xiafs_find_entry(dir, name, len, &de, NULL);
-    if (bh) {
-        brelse(bh);
-	iput(dir);
-	iput(oldinode);
-	return -EEXIST;
-    }
-    bh = xiafs_add_entry(dir, name, len, &de, NULL);
-    if (!bh) {
-        iput(dir);
-	iput(oldinode);
-	return -ENOSPC;
-    }
-    de->d_ino = oldinode->i_ino;
-    mark_buffer_dirty(bh, 1);
-    brelse(bh);
-    iput(dir);
-    oldinode->i_nlink++;
-    oldinode->i_ctime = CURRENT_TIME;
-    oldinode->i_dirt = 1;
-    iput(oldinode);
-    return 0;
-}
-
-static int subdir(struct inode * new_inode, struct inode * old_inode)
-{
-    int ino;
-    int result;
-
-    new_inode->i_count++;
-    result = 0;
-    for (;;) {
-        if (new_inode == old_inode) {
-	    result = 1;
-	    break;
-	}
-	if (new_inode->i_dev != old_inode->i_dev)
-	    break;
-	ino = new_inode->i_ino;
-	if (xiafs_lookup(new_inode,"..",2,&new_inode))
-	    break;
-	if (new_inode->i_ino == ino)
-	    break;
-    }
-    iput(new_inode);
-    return result;
-}
-
-#define PARENT_INO(buffer) \
-    (((struct xiafs_direct *) ((u_char *)(buffer) + 12))->d_ino)
-
-/*
- * rename uses retry to avoid race-conditions: at least they should be minimal.
- * it tries to allocate all the blocks, then sanity-checks, and if the sanity-
- * checks fail, it tries to restart itself again. Very practical - no changes
- * are done until we know everything works ok.. and then all the changes can be
- * done in one fell swoop when we have claimed all the buffers needed.
- *
- * Anybody can rename anything with this: the permission checks are left to the
- * higher-level routines.
- */
-static int do_xiafs_rename(struct inode * old_dir, const char * old_name, 
-			 int old_len, struct inode * new_dir, 
-			 const char * new_name, int new_len,
-			 int must_be_dir)
-{
-    struct inode * old_inode, * new_inode;
-    struct buffer_head * old_bh, * new_bh, * dir_bh;
-    struct xiafs_direct * old_de, * old_de_pre, * new_de, * new_de_pre;
-    int retval;
-
-try_again:
-    old_inode = new_inode = NULL;
-    old_bh = new_bh = dir_bh = NULL;
-    old_bh = xiafs_find_entry(old_dir, old_name, old_len, &old_de, &old_de_pre);
-    retval = -ENOENT;
-    if (!old_bh)
-        goto end_rename;
-    old_inode = __iget(old_dir->i_sb, old_de->d_ino, 0); /* don't cross mnt-points */
-    if (!old_inode)
-        goto end_rename;
-    if (must_be_dir && !S_ISDIR(old_inode->i_mode))
-	goto end_rename;
-    retval = -EPERM;
-    if ((old_dir->i_mode & S_ISVTX) && 
-	    current->fsuid != old_inode->i_uid &&
-	    current->fsuid != old_dir->i_uid && !fsuser())
-        goto end_rename;
-    new_bh = xiafs_find_entry(new_dir, new_name, new_len, &new_de, NULL);
-    if (new_bh) {
-        new_inode = __iget(new_dir->i_sb, new_de->d_ino, 0);
-	if (!new_inode) {
-	    brelse(new_bh);
-	    new_bh = NULL;
-	}
-    }
-    if (new_inode == old_inode) {
-        retval = 0;
-	goto end_rename;
-    }
-    if (new_inode && S_ISDIR(new_inode->i_mode)) {
-        retval = -EEXIST;
-	goto end_rename;
-    }
-    retval = -EPERM;
-    if (new_inode && (new_dir->i_mode & S_ISVTX) && 
-	    current->fsuid != new_inode->i_uid &&
- 	    current->fsuid != new_dir->i_uid && !fsuser())
-        goto end_rename;
-    if (S_ISDIR(old_inode->i_mode)) {
-        retval = -EEXIST;
-	if (new_bh)
-	    goto end_rename;
-	if ((retval = permission(old_inode, MAY_WRITE)) != 0)
-	    goto end_rename;
-	retval = -EINVAL;
-	if (subdir(new_dir, old_inode))
-	    goto end_rename;
-	retval = -EIO;
-	dir_bh = xiafs_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_dir->i_nlink > 64000)
-	    goto end_rename;
-    }
-    if (!new_bh)
-        new_bh = xiafs_add_entry(new_dir, new_name, new_len, &new_de, &new_de_pre);
-    retval = -ENOSPC;
-    if (!new_bh) 
-        goto end_rename;
-    /* sanity checking */
-    if ( (new_inode && (new_de->d_ino != new_inode->i_ino))
-	    || (new_de->d_ino && !new_inode)
-	    || (old_de->d_ino != old_inode->i_ino)) {
-        xiafs_rm_entry(new_de, new_de_pre);
-        brelse(old_bh);
-	brelse(new_bh);
-	brelse(dir_bh);
-	iput(old_inode);
-	iput(new_inode);
-	current->counter=0;
-	schedule();
-	goto try_again;
-    }
-    xiafs_rm_entry(old_de, old_de_pre);
-    new_de->d_ino = old_inode->i_ino;
-    if (new_inode) {
-        new_inode->i_nlink--;
-	new_inode->i_dirt = 1;
-    }
-    mark_buffer_dirty(old_bh, 1);
-    mark_buffer_dirty(new_bh, 1);
-    if (dir_bh) {
-        PARENT_INO(dir_bh->b_data) = new_dir->i_ino;
-	mark_buffer_dirty(dir_bh, 1);
-	old_dir->i_nlink--;
-	new_dir->i_nlink++;
-	old_dir->i_dirt = 1;
-	new_dir->i_dirt = 1;
-    }
-    retval = 0;
-end_rename:
-    brelse(dir_bh);
-    brelse(old_bh);
-    brelse(new_bh);
-    iput(old_inode);
-    iput(new_inode);
-    iput(old_dir);
-    iput(new_dir);
-    return retval;
-}
-
-/*
- * Ok, rename also locks out other renames, as they can change the parent of
- * a directory, and we don't want any races. Other races are checked for by
- * "do_rename()", which restarts if there are inconsistencies.
- *
- * Note that there is no race between different filesystems: it's only within
- * the same device that races occur: many renames can happen at once, as long
- * as they are on different partitions.
- */
-int xiafs_rename(struct inode * old_dir, const char * old_name, int old_len,
-	struct inode * new_dir, const char * new_name, int new_len,
-	int must_be_dir)
-{
-    static struct wait_queue * wait = NULL;
-    static int lock = 0;
-    int result;
-
-    while (lock)
-        sleep_on(&wait);
-    lock = 1;
-    result = do_xiafs_rename(old_dir, old_name, old_len,
-			   new_dir, new_name, new_len,
-			   must_be_dir);
-    lock = 0;
-    wake_up(&wait);
-    return result;
-}

FUNET's LINUX-ADM group, linux-adm@nic.funet.fi
TCL-scripts by Sam Shen, slshen@lbl.gov