dir.c

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		*result = dir;
		return 0;
	}
	if ((NFS_SERVER(dir)->flags & NFS_MOUNT_NOAC)
	    || !nfs_lookup_cache_lookup(dir, name, &fhandle, &fattr)) {
		if ((error = nfs_proc_lookup(NFS_SERVER(dir), NFS_FH(dir),
		    name, &fhandle, &fattr))) {
			iput(dir);
			return error;
		}
		nfs_lookup_cache_add(dir, name, &fhandle, &fattr);
	}
	if (!(*result = nfs_fhget(dir->i_sb, &fhandle, &fattr))) {
		iput(dir);
		return -EACCES;
	}
	iput(dir);
	return 0;
}

static int nfs_create(struct inode *dir, const char *name, int len, int mode,
		      struct inode **result)
{
	struct nfs_sattr sattr;
	struct nfs_fattr fattr;
	struct nfs_fh fhandle;
	int error;

	*result = NULL;
	if (!dir || !S_ISDIR(dir->i_mode)) {
		printk("nfs_create: inode is NULL or not a directory\n");
		iput(dir);
		return -ENOENT;
	}
	if (len > NFS_MAXNAMLEN) {
		iput(dir);
		return -ENAMETOOLONG;
	}
	sattr.mode = mode;
	sattr.uid = sattr.gid = sattr.size = (unsigned) -1;
	sattr.atime.seconds = sattr.mtime.seconds = (unsigned) -1;
	if ((error = nfs_proc_create(NFS_SERVER(dir), NFS_FH(dir),
		name, &sattr, &fhandle, &fattr))) {
		iput(dir);
		return error;
	}
	if (!(*result = nfs_fhget(dir->i_sb, &fhandle, &fattr))) {
		iput(dir);
		return -EACCES;
	}
	nfs_lookup_cache_add(dir, name, &fhandle, &fattr);
	iput(dir);
	return 0;
}

static int nfs_mknod(struct inode *dir, const char *name, int len,
		     int mode, int rdev)
{
	struct nfs_sattr sattr;
	struct nfs_fattr fattr;
	struct nfs_fh fhandle;
	int error;

	if (!dir || !S_ISDIR(dir->i_mode)) {
		printk("nfs_mknod: inode is NULL or not a directory\n");
		iput(dir);
		return -ENOENT;
	}
	if (len > NFS_MAXNAMLEN) {
		iput(dir);
		return -ENAMETOOLONG;
	}
	sattr.mode = mode;
	sattr.uid = sattr.gid = (unsigned) -1;
	if (S_ISCHR(mode) || S_ISBLK(mode))
		sattr.size = rdev; /* get out your barf bag */
	else
		sattr.size = (unsigned) -1;
	sattr.atime.seconds = sattr.mtime.seconds = (unsigned) -1;
	error = nfs_proc_create(NFS_SERVER(dir), NFS_FH(dir),
		name, &sattr, &fhandle, &fattr);
	if (!error)
	{
		nfs_lookup_cache_add(dir, name, &fhandle, &fattr);
		/* The parent dir inode count may have changed ! */
		nfs_lookup_cache_remove( NULL, dir, NULL);
	}
		
	iput(dir);
	return error;
}

static int nfs_mkdir(struct inode *dir, const char *name, int len, int mode)
{
	struct nfs_sattr sattr;
	struct nfs_fattr fattr;
	struct nfs_fh fhandle;
	int error;

	if (!dir || !S_ISDIR(dir->i_mode)) {
		printk("nfs_mkdir: inode is NULL or not a directory\n");
		iput(dir);
		return -ENOENT;
	}
	if (len > NFS_MAXNAMLEN) {
		iput(dir);
		return -ENAMETOOLONG;
	}
	sattr.mode = mode;
	sattr.uid = sattr.gid = sattr.size = (unsigned) -1;
	sattr.atime.seconds = sattr.mtime.seconds = (unsigned) -1;
	error = nfs_proc_mkdir(NFS_SERVER(dir), NFS_FH(dir),
		name, &sattr, &fhandle, &fattr);
	if (!error) {
		if (fattr.fileid == dir->i_ino)
			printk("Sony NewsOS 4.1R buggy nfs server?\n");
		else
			nfs_lookup_cache_add(dir, name, &fhandle, &fattr);
	}
	iput(dir);
	/* The parent dir link count may have changed */
	nfs_lookup_cache_remove( NULL, dir, NULL);
	return error;
}

static int nfs_rmdir(struct inode *dir, const char *name, int len)
{
	int error;

	if (!dir || !S_ISDIR(dir->i_mode)) {
		printk("nfs_rmdir: inode is NULL or not a directory\n");
		iput(dir);
		return -ENOENT;
	}
	if (len > NFS_MAXNAMLEN) {
		iput(dir);
		return -ENAMETOOLONG;
	}
	error = nfs_proc_rmdir(NFS_SERVER(dir), NFS_FH(dir), name);
	nfs_lookup_cache_remove(dir, NULL, name);
	iput(dir);
	return error;
}

static int nfs_sillyrename(struct inode *dir, const char *name, int len)
{
	struct inode	*inode;
	char		silly[16];
	int		slen, ret;

	dir->i_count++;
	if (nfs_lookup(dir, name, len, &inode) < 0)
		return -EIO;		/* arbitrary */
	if (inode->i_count == 1 || NFS_RENAMED_DIR(inode)) {
		iput(inode);
		return -EIO;
	}
	slen = sprintf(silly, ".nfs%ld", inode->i_ino);

	if (len == slen && !strncmp(name, silly, len)) {
		iput(inode);
		return -EIO;		/* DWIM */
	}
	ret = nfs_proc_rename(NFS_SERVER(dir), NFS_FH(dir), name,
					       NFS_FH(dir), silly, 0);
	if (ret >= 0) {
		nfs_lookup_cache_remove(dir, NULL, name);
		nfs_lookup_cache_remove(dir, NULL, silly);
		NFS_RENAMED_DIR(inode) = dir;
		dir->i_count++;
	}
	iput(inode);
	return ret;
}

void nfs_sillyrename_cleanup(struct inode *inode)
{
	struct inode	*dir = NFS_RENAMED_DIR(inode);
	char		silly[14];
	int		error, slen;

	slen = sprintf(silly, ".nfs%ld", inode->i_ino);
	if ((error = nfs_unlink(dir, silly, slen)) < 0) {
		printk("NFS silly_rename cleanup failed (err = %d)\n",
					-error);
	}
	NFS_RENAMED_DIR(inode) = NULL;
}

static int nfs_unlink(struct inode *dir, const char *name, int len)
{
	int error;

	if (!dir || !S_ISDIR(dir->i_mode)) {
		printk("nfs_unlink: inode is NULL or not a directory\n");
		iput(dir);
		return -ENOENT;
	}
	if (len > NFS_MAXNAMLEN) {
		iput(dir);
		return -ENAMETOOLONG;
	}
	if ((error = nfs_sillyrename(dir, name, len)) < 0) {
		error = nfs_proc_remove(NFS_SERVER(dir), NFS_FH(dir), name);
		nfs_lookup_cache_remove(dir, NULL, name);
	}
	iput(dir);
	return error;
}

static int nfs_symlink(struct inode *dir, const char *name, int len,
		       const char *symname)
{
	struct nfs_sattr sattr;
	int error;

	if (!dir || !S_ISDIR(dir->i_mode)) {
		printk("nfs_symlink: inode is NULL or not a directory\n");
		iput(dir);
		return -ENOENT;
	}
	if (len > NFS_MAXNAMLEN) {
		iput(dir);
		return -ENAMETOOLONG;
	}
	if (strlen(symname) > NFS_MAXPATHLEN) {
		iput(dir);
		return -ENAMETOOLONG;
	}
	sattr.mode = S_IFLNK | S_IRWXUGO; /* SunOS 4.1.2 crashes without this! */
	sattr.uid = sattr.gid = sattr.size = (unsigned) -1;
	sattr.atime.seconds = sattr.mtime.seconds = (unsigned) -1;
	error = nfs_proc_symlink(NFS_SERVER(dir), NFS_FH(dir),
		name, symname, &sattr);
	iput(dir);
	return error;
}

static int nfs_link(struct inode *oldinode, struct inode *dir,
		    const char *name, int len)
{
	int error;

	if (!oldinode) {
		printk("nfs_link: old inode is NULL\n");
		iput(oldinode);
		iput(dir);
		return -ENOENT;
	}
	if (!dir || !S_ISDIR(dir->i_mode)) {
		printk("nfs_link: dir is NULL or not a directory\n");
		iput(oldinode);
		iput(dir);
		return -ENOENT;
	}
	if (len > NFS_MAXNAMLEN) {
		iput(oldinode);
		iput(dir);
		return -ENAMETOOLONG;
	}
	error = nfs_proc_link(NFS_SERVER(oldinode), NFS_FH(oldinode),
		NFS_FH(dir), name);

	nfs_lookup_cache_remove(dir, oldinode, NULL);
	NFS_CACHEINV(oldinode);
	iput(oldinode);
	iput(dir);
	return error;
}

static int nfs_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)
{
	int error;

	if (!old_dir || !S_ISDIR(old_dir->i_mode)) {
		printk("nfs_rename: old inode is NULL or not a directory\n");
		iput(old_dir);
		iput(new_dir);
		return -ENOENT;
	}
	if (!new_dir || !S_ISDIR(new_dir->i_mode)) {
		printk("nfs_rename: new inode is NULL or not a directory\n");
		iput(old_dir);
		iput(new_dir);
		return -ENOENT;
	}
	if (old_len > NFS_MAXNAMLEN || new_len > NFS_MAXNAMLEN) {
		iput(old_dir);
		iput(new_dir);
		return -ENAMETOOLONG;
	}
	error = nfs_proc_rename(NFS_SERVER(old_dir),
		NFS_FH(old_dir), old_name,
		NFS_FH(new_dir), new_name,
		must_be_dir);

	nfs_lookup_cache_remove(old_dir, NULL, old_name);
	nfs_lookup_cache_remove(new_dir, NULL, new_name);
	iput(old_dir);
	iput(new_dir);
	return error;
}

/*
 * Many nfs protocol calls return the new file attributes after
 * an operation.  Here we update the inode to reflect the state
 * of the server's inode.
 */

void nfs_refresh_inode(struct inode *inode, struct nfs_fattr *fattr)
{
	int was_empty;

	if (!inode || !fattr) {
		printk("nfs_refresh_inode: inode or fattr is NULL\n");
		return;
	}
	if (inode->i_ino != fattr->fileid) {
		printk("nfs_refresh_inode: inode number mismatch\n");
		return;
	}
	was_empty = (inode->i_mode == 0);
	
	/*
	 * Some (broken?) NFS servers return 0 as the file type.
	 * We'll assume that 0 means the file type has not changed.
	 */
	if(!(fattr->mode & S_IFMT)){
		inode->i_mode = (inode->i_mode & S_IFMT) |
				(fattr->mode & ~S_IFMT);
	}else{
		inode->i_mode = fattr->mode;
	}
	inode->i_nlink = fattr->nlink;
	inode->i_uid = fattr->uid;
	inode->i_gid = fattr->gid;

	/* Size changed from outside: invalidate caches on next read */
	if (inode->i_size != fattr->size)
		NFS_CACHEINV(inode);
	if (NFS_OLDMTIME(inode) != fattr->mtime.seconds)
		NFS_ATTRTIMEO(inode) = NFS_MINATTRTIMEO(inode);
	inode->i_size = fattr->size;
	if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode))
		inode->i_rdev = to_kdev_t(fattr->rdev);
	else
		inode->i_rdev = 0;
	inode->i_blocks = fattr->blocks;
	inode->i_atime = fattr->atime.seconds;
	inode->i_mtime = fattr->mtime.seconds;
	inode->i_ctime = fattr->ctime.seconds;
	if (S_ISREG(inode->i_mode))
		inode->i_op = &nfs_file_inode_operations;
	else if (S_ISDIR(inode->i_mode))
		inode->i_op = &nfs_dir_inode_operations;
	else if (S_ISLNK(inode->i_mode))
		inode->i_op = &nfs_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)) {
		if (was_empty)
			init_fifo(inode);
	} else
		inode->i_op = NULL;
	nfs_lookup_cache_refresh(inode, fattr);
}