fs/orangefs/dir.c - kernel/common.git - Git at Google

 /*
  * (C) 2001 Clemson University and The University of Chicago
  *
  * See COPYING in top-level directory.
  */

 #include "protocol.h"
 #include "orangefs-kernel.h"
 #include "orangefs-bufmap.h"

 /*
  * decode routine used by kmod to deal with the blob sent from
  * userspace for readdirs. The blob contains zero or more of these
  * sub-blobs:
  *   __u32 - represents length of the character string that follows.
  *   string - between 1 and ORANGEFS_NAME_MAX bytes long.
  *   padding - (if needed) to cause the __u32 plus the string to be
  *             eight byte aligned.
  *   khandle - sizeof(khandle) bytes.
  */
 static long decode_dirents(char *ptr, size_t size,
                            struct orangefs_readdir_response_s *readdir)
 {
 	int i;
 	struct orangefs_readdir_response_s *rd =
 		(struct orangefs_readdir_response_s *) ptr;
 	char *buf = ptr;
 	int khandle_size = sizeof(struct orangefs_khandle);
 	size_t offset = offsetof(struct orangefs_readdir_response_s,
 				dirent_array);
 	/* 8 reflects eight byte alignment */
 	int smallest_blob = khandle_size + 8;
 	__u32 len;
 	int aligned_len;
 	int sizeof_u32 = sizeof(__u32);
 	long ret;

 	gossip_debug(GOSSIP_DIR_DEBUG, "%s: size:%zu:\n", __func__, size);

 	/* size is = offset on empty dirs, > offset on non-empty dirs... */
 	if (size < offset) {
 		gossip_err("%s: size:%zu: offset:%zu:\n",
 			   __func__,
 			   size,
 			   offset);
 		ret = -EINVAL;
 		goto out;
 	}

         if ((size == offset) && (readdir->orangefs_dirent_outcount != 0)) {
 		gossip_err("%s: size:%zu: dirent_outcount:%d:\n",
 			   __func__,
 			   size,
 			   readdir->orangefs_dirent_outcount);
 		ret = -EINVAL;
 		goto out;
 	}

 	readdir->token = rd->token;
 	readdir->orangefs_dirent_outcount = rd->orangefs_dirent_outcount;
 	readdir->dirent_array = kcalloc(readdir->orangefs_dirent_outcount,
 					sizeof(*readdir->dirent_array),
 					GFP_KERNEL);
 	if (readdir->dirent_array == NULL) {
 		gossip_err("%s: kcalloc failed.\n", __func__);
 		ret = -ENOMEM;
 		goto out;
 	}

 	buf += offset;
 	size -= offset;

 	for (i = 0; i < readdir->orangefs_dirent_outcount; i++) {
 		if (size < smallest_blob) {
 			gossip_err("%s: size:%zu: smallest_blob:%d:\n",
 				   __func__,
 				   size,
 				   smallest_blob);
 			ret = -EINVAL;
 			goto free;
 		}

 		len = *(__u32 *)buf;
 		if ((len < 1) || (len > ORANGEFS_NAME_MAX)) {
 			gossip_err("%s: len:%d:\n", __func__, len);
 			ret = -EINVAL;
 			goto free;
 		}

 		gossip_debug(GOSSIP_DIR_DEBUG,
 			     "%s: size:%zu: len:%d:\n",
 			     __func__,
 			     size,
 			     len);

 		readdir->dirent_array[i].d_name = buf + sizeof_u32;
 		readdir->dirent_array[i].d_length = len;

 		/*
 		 * Calculate "aligned" length of this string and its
 		 * associated __u32 descriptor.
 		 */
 		aligned_len = ((sizeof_u32 + len + 1) + 7) & ~7;
 		gossip_debug(GOSSIP_DIR_DEBUG,
 			     "%s: aligned_len:%d:\n",
 			     __func__,
 			     aligned_len);

 		/*
 		 * The end of the blob should coincide with the end
 		 * of the last sub-blob.
 		 */
 		if (size < aligned_len + khandle_size) {
 			gossip_err("%s: ran off the end of the blob.\n",
 				   __func__);
 			ret = -EINVAL;
 			goto free;
 		}
 		size -= aligned_len + khandle_size;

 		buf += aligned_len;

 		readdir->dirent_array[i].khandle =
 			*(struct orangefs_khandle *) buf;
 		buf += khandle_size;
 	}
 	ret = buf - ptr;
 	gossip_debug(GOSSIP_DIR_DEBUG, "%s: returning:%ld:\n", __func__, ret);
 	goto out;

 free:
 	kfree(readdir->dirent_array);
 	readdir->dirent_array = NULL;

 out:
 	return ret;
 }

 /*
  * Read directory entries from an instance of an open directory.
  */
 static int orangefs_readdir(struct file *file, struct dir_context *ctx)
 {
 	int ret = 0;
 	int buffer_index;
 	/*
 	 * ptoken supports Orangefs' distributed directory logic, added
 	 * in 2.9.2.
 	 */
 	__u64 *ptoken = file->private_data;
 	__u64 pos = 0;
 	ino_t ino = 0;
 	struct dentry *dentry = file->f_path.dentry;
 	struct orangefs_kernel_op_s *new_op = NULL;
 	struct orangefs_inode_s *orangefs_inode = ORANGEFS_I(dentry->d_inode);
 	struct orangefs_readdir_response_s readdir_response;
 	void *dents_buf;
 	int i = 0;
 	int len = 0;
 	ino_t current_ino = 0;
 	char *current_entry = NULL;
 	long bytes_decoded;

 	gossip_debug(GOSSIP_DIR_DEBUG,
 		     "%s: ctx->pos:%lld, ptoken = %llu\n",
 		     __func__,
 		     lld(ctx->pos),
 		     llu(*ptoken));

 	pos = (__u64) ctx->pos;

 	/* are we done? */
 	if (pos == ORANGEFS_READDIR_END) {
 		gossip_debug(GOSSIP_DIR_DEBUG,
 			     "Skipping to termination path\n");
 		return 0;
 	}

 	gossip_debug(GOSSIP_DIR_DEBUG,
 		     "orangefs_readdir called on %pd (pos=%llu)\n",
 		     dentry, llu(pos));

 	memset(&readdir_response, 0, sizeof(readdir_response));

 	new_op = op_alloc(ORANGEFS_VFS_OP_READDIR);
 	if (!new_op)
 		return -ENOMEM;

 	/*
 	 * Only the indices are shared. No memory is actually shared, but the
 	 * mechanism is used.
 	 */
 	new_op->uses_shared_memory = 1;
 	new_op->upcall.req.readdir.refn = orangefs_inode->refn;
 	new_op->upcall.req.readdir.max_dirent_count =
 	    ORANGEFS_MAX_DIRENT_COUNT_READDIR;

 	gossip_debug(GOSSIP_DIR_DEBUG,
 		     "%s: upcall.req.readdir.refn.khandle: %pU\n",
 		     __func__,
 		     &new_op->upcall.req.readdir.refn.khandle);

 	new_op->upcall.req.readdir.token = *ptoken;

 get_new_buffer_index:
 	buffer_index = orangefs_readdir_index_get();
 	if (buffer_index < 0) {
 		ret = buffer_index;
 		gossip_lerr("orangefs_readdir: orangefs_readdir_index_get() failure (%d)\n",
 			    ret);
 		goto out_free_op;
 	}
 	new_op->upcall.req.readdir.buf_index = buffer_index;

 	ret = service_operation(new_op,
 				"orangefs_readdir",
 				get_interruptible_flag(dentry->d_inode));

 	gossip_debug(GOSSIP_DIR_DEBUG,
 		     "Readdir downcall status is %d.  ret:%d\n",
 		     new_op->downcall.status,
 		     ret);

 	orangefs_readdir_index_put(buffer_index);

 	if (ret == -EAGAIN && op_state_purged(new_op)) {
 		/* Client-core indices are invalid after it restarted. */
 		gossip_debug(GOSSIP_DIR_DEBUG,
 			"%s: Getting new buffer_index for retry of readdir..\n",
 			 __func__);
 		goto get_new_buffer_index;
 	}

 	if (ret == -EIO && op_state_purged(new_op)) {
 		gossip_err("%s: Client is down. Aborting readdir call.\n",
 			__func__);
 		goto out_free_op;
 	}

 	if (ret < 0 || new_op->downcall.status != 0) {
 		gossip_debug(GOSSIP_DIR_DEBUG,
 			     "Readdir request failed.  Status:%d\n",
 			     new_op->downcall.status);
 		if (ret >= 0)
 			ret = new_op->downcall.status;
 		goto out_free_op;
 	}

 	dents_buf = new_op->downcall.trailer_buf;
 	if (dents_buf == NULL) {
 		gossip_err("Invalid NULL buffer in readdir response\n");
 		ret = -ENOMEM;
 		goto out_free_op;
 	}

 	bytes_decoded = decode_dirents(dents_buf, new_op->downcall.trailer_size,
 					&readdir_response);
 	if (bytes_decoded < 0) {
 		ret = bytes_decoded;
 		gossip_err("Could not decode readdir from buffer %d\n", ret);
 		goto out_vfree;
 	}

 	if (bytes_decoded != new_op->downcall.trailer_size) {
 		gossip_err("orangefs_readdir: # bytes decoded (%ld) "
 			   "!= trailer size (%ld)\n",
 			   bytes_decoded,
 			   (long)new_op->downcall.trailer_size);
 		ret = -EINVAL;
 		goto out_destroy_handle;
 	}

 	/*
 	 *  orangefs doesn't actually store dot and dot-dot, but
 	 *  we need to have them represented.
 	 */
 	if (pos == 0) {
 		ino = get_ino_from_khandle(dentry->d_inode);
 		gossip_debug(GOSSIP_DIR_DEBUG,
 			     "%s: calling dir_emit of \".\" with pos = %llu\n",
 			     __func__,
 			     llu(pos));
 		ret = dir_emit(ctx, ".", 1, ino, DT_DIR);
 		pos += 1;
 	}

 	if (pos == 1) {
 		ino = get_parent_ino_from_dentry(dentry);
 		gossip_debug(GOSSIP_DIR_DEBUG,
 			     "%s: calling dir_emit of \"..\" with pos = %llu\n",
 			     __func__,
 			     llu(pos));
 		ret = dir_emit(ctx, "..", 2, ino, DT_DIR);
 		pos += 1;
 	}

 	/*
 	 * we stored ORANGEFS_ITERATE_NEXT in ctx->pos last time around
 	 * to prevent "finding" dot and dot-dot on any iteration
 	 * other than the first.
 	 */
 	if (ctx->pos == ORANGEFS_ITERATE_NEXT)
 		ctx->pos = 0;

 	gossip_debug(GOSSIP_DIR_DEBUG,
 		     "%s: dirent_outcount:%d:\n",
 		     __func__,
 		     readdir_response.orangefs_dirent_outcount);
 	for (i = ctx->pos;
 	     i < readdir_response.orangefs_dirent_outcount;
 	     i++) {
 		len = readdir_response.dirent_array[i].d_length;
 		current_entry = readdir_response.dirent_array[i].d_name;
 		current_ino = orangefs_khandle_to_ino(
 			&readdir_response.dirent_array[i].khandle);

 		gossip_debug(GOSSIP_DIR_DEBUG,
 			     "calling dir_emit for %s with len %d"
 			     ", ctx->pos %ld\n",
 			     current_entry,
 			     len,
 			     (unsigned long)ctx->pos);
 		/*
 		 * type is unknown. We don't return object type
 		 * in the dirent_array. This leaves getdents
 		 * clueless about type.
 		 */
 		ret =
 		    dir_emit(ctx, current_entry, len, current_ino, DT_UNKNOWN);
 		if (!ret)
 			break;
 		ctx->pos++;
 		gossip_debug(GOSSIP_DIR_DEBUG,
 			      "%s: ctx->pos:%lld\n",
 			      __func__,
 			      lld(ctx->pos));

 	}

 	/*
 	 * we ran all the way through the last batch, set up for
 	 * getting another batch...
 	 */
 	if (ret) {
 		*ptoken = readdir_response.token;
 		ctx->pos = ORANGEFS_ITERATE_NEXT;
 	}

 	/*
 	 * Did we hit the end of the directory?
 	 */
 	if (readdir_response.token == ORANGEFS_READDIR_END) {
 		gossip_debug(GOSSIP_DIR_DEBUG,
 		"End of dir detected; setting ctx->pos to ORANGEFS_READDIR_END.\n");
 		ctx->pos = ORANGEFS_READDIR_END;
 	}

 out_destroy_handle:
 	/* kfree(NULL) is safe */
 	kfree(readdir_response.dirent_array);
 out_vfree:
 	gossip_debug(GOSSIP_DIR_DEBUG, "vfree %p\n", dents_buf);
 	vfree(dents_buf);
 out_free_op:
 	op_release(new_op);
 	gossip_debug(GOSSIP_DIR_DEBUG, "orangefs_readdir returning %d\n", ret);
 	return ret;
 }

 static int orangefs_dir_open(struct inode *inode, struct file *file)
 {
 	__u64 *ptoken;

 	file->private_data = kmalloc(sizeof(__u64), GFP_KERNEL);
 	if (!file->private_data)
 		return -ENOMEM;

 	ptoken = file->private_data;
 	*ptoken = ORANGEFS_READDIR_START;
 	return 0;
 }

 static int orangefs_dir_release(struct inode *inode, struct file *file)
 {
 	orangefs_flush_inode(inode);
 	kfree(file->private_data);
 	return 0;
 }

 /** ORANGEFS implementation of VFS directory operations */
 const struct file_operations orangefs_dir_operations = {
 	.read = generic_read_dir,
 	.iterate = orangefs_readdir,
 	.open = orangefs_dir_open,
 	.release = orangefs_dir_release,
 };
	/*
	* (C) 2001 Clemson University and The University of Chicago
	*
	* See COPYING in top-level directory.
	*/

	#include "protocol.h"
	#include "orangefs-kernel.h"
	#include "orangefs-bufmap.h"

	/*
	* decode routine used by kmod to deal with the blob sent from
	* userspace for readdirs. The blob contains zero or more of these
	* sub-blobs:
	* __u32 - represents length of the character string that follows.
	* string - between 1 and ORANGEFS_NAME_MAX bytes long.
	* padding - (if needed) to cause the __u32 plus the string to be
	* eight byte aligned.
	* khandle - sizeof(khandle) bytes.
	*/
	static long decode_dirents(char *ptr, size_t size,
	struct orangefs_readdir_response_s *readdir)
	{
	int i;
	struct orangefs_readdir_response_s *rd =
	(struct orangefs_readdir_response_s *) ptr;
	char *buf = ptr;
	int khandle_size = sizeof(struct orangefs_khandle);
	size_t offset = offsetof(struct orangefs_readdir_response_s,
	dirent_array);
	/* 8 reflects eight byte alignment */
	int smallest_blob = khandle_size + 8;
	__u32 len;
	int aligned_len;
	int sizeof_u32 = sizeof(__u32);
	long ret;

	gossip_debug(GOSSIP_DIR_DEBUG, "%s: size:%zu:\n", __func__, size);

	/* size is = offset on empty dirs, > offset on non-empty dirs... */
	if (size < offset) {
	gossip_err("%s: size:%zu: offset:%zu:\n",
	__func__,
	size,
	offset);
	ret = -EINVAL;
	goto out;
	}

	if ((size == offset) && (readdir->orangefs_dirent_outcount != 0)) {
	gossip_err("%s: size:%zu: dirent_outcount:%d:\n",
	__func__,
	size,
	readdir->orangefs_dirent_outcount);
	ret = -EINVAL;
	goto out;
	}

	readdir->token = rd->token;
	readdir->orangefs_dirent_outcount = rd->orangefs_dirent_outcount;
	readdir->dirent_array = kcalloc(readdir->orangefs_dirent_outcount,
	sizeof(*readdir->dirent_array),
	GFP_KERNEL);
	if (readdir->dirent_array == NULL) {
	gossip_err("%s: kcalloc failed.\n", __func__);
	ret = -ENOMEM;
	goto out;
	}

	buf += offset;
	size -= offset;

	for (i = 0; i < readdir->orangefs_dirent_outcount; i++) {
	if (size < smallest_blob) {
	gossip_err("%s: size:%zu: smallest_blob:%d:\n",
	__func__,
	size,
	smallest_blob);
	ret = -EINVAL;
	goto free;
	}

	len = (__u32 )buf;
	if ((len < 1) \|\| (len > ORANGEFS_NAME_MAX)) {
	gossip_err("%s: len:%d:\n", __func__, len);
	ret = -EINVAL;
	goto free;
	}

	gossip_debug(GOSSIP_DIR_DEBUG,
	"%s: size:%zu: len:%d:\n",
	__func__,
	size,
	len);

	readdir->dirent_array[i].d_name = buf + sizeof_u32;
	readdir->dirent_array[i].d_length = len;

	/*
	* Calculate "aligned" length of this string and its
	* associated __u32 descriptor.
	*/
	aligned_len = ((sizeof_u32 + len + 1) + 7) & ~7;
	gossip_debug(GOSSIP_DIR_DEBUG,
	"%s: aligned_len:%d:\n",
	__func__,
	aligned_len);

	/*
	* The end of the blob should coincide with the end
	* of the last sub-blob.
	*/
	if (size < aligned_len + khandle_size) {
	gossip_err("%s: ran off the end of the blob.\n",
	__func__);
	ret = -EINVAL;
	goto free;
	}
	size -= aligned_len + khandle_size;

	buf += aligned_len;

	readdir->dirent_array[i].khandle =
	(struct orangefs_khandle ) buf;
	buf += khandle_size;
	}
	ret = buf - ptr;
	gossip_debug(GOSSIP_DIR_DEBUG, "%s: returning:%ld:\n", __func__, ret);
	goto out;

	free:
	kfree(readdir->dirent_array);
	readdir->dirent_array = NULL;

	out:
	return ret;
	}

	/*
	* Read directory entries from an instance of an open directory.
	*/
	static int orangefs_readdir(struct file file, struct dir_context ctx)
	{
	int ret = 0;
	int buffer_index;
	/*
	* ptoken supports Orangefs' distributed directory logic, added
	* in 2.9.2.
	*/
	__u64 *ptoken = file->private_data;
	__u64 pos = 0;
	ino_t ino = 0;
	struct dentry *dentry = file->f_path.dentry;
	struct orangefs_kernel_op_s *new_op = NULL;
	struct orangefs_inode_s *orangefs_inode = ORANGEFS_I(dentry->d_inode);
	struct orangefs_readdir_response_s readdir_response;
	void *dents_buf;
	int i = 0;
	int len = 0;
	ino_t current_ino = 0;
	char *current_entry = NULL;
	long bytes_decoded;

	gossip_debug(GOSSIP_DIR_DEBUG,
	"%s: ctx->pos:%lld, ptoken = %llu\n",
	__func__,
	lld(ctx->pos),
	llu(*ptoken));

	pos = (__u64) ctx->pos;

	/* are we done? */
	if (pos == ORANGEFS_READDIR_END) {
	gossip_debug(GOSSIP_DIR_DEBUG,
	"Skipping to termination path\n");
	return 0;
	}

	gossip_debug(GOSSIP_DIR_DEBUG,
	"orangefs_readdir called on %pd (pos=%llu)\n",
	dentry, llu(pos));

	memset(&readdir_response, 0, sizeof(readdir_response));

	new_op = op_alloc(ORANGEFS_VFS_OP_READDIR);
	if (!new_op)
	return -ENOMEM;

	/*
	* Only the indices are shared. No memory is actually shared, but the
	* mechanism is used.
	*/
	new_op->uses_shared_memory = 1;
	new_op->upcall.req.readdir.refn = orangefs_inode->refn;
	new_op->upcall.req.readdir.max_dirent_count =
	ORANGEFS_MAX_DIRENT_COUNT_READDIR;

	gossip_debug(GOSSIP_DIR_DEBUG,
	"%s: upcall.req.readdir.refn.khandle: %pU\n",
	__func__,
	&new_op->upcall.req.readdir.refn.khandle);

	new_op->upcall.req.readdir.token = *ptoken;

	get_new_buffer_index:
	buffer_index = orangefs_readdir_index_get();
	if (buffer_index < 0) {
	ret = buffer_index;
	gossip_lerr("orangefs_readdir: orangefs_readdir_index_get() failure (%d)\n",
	ret);
	goto out_free_op;
	}
	new_op->upcall.req.readdir.buf_index = buffer_index;

	ret = service_operation(new_op,
	"orangefs_readdir",
	get_interruptible_flag(dentry->d_inode));

	gossip_debug(GOSSIP_DIR_DEBUG,
	"Readdir downcall status is %d. ret:%d\n",
	new_op->downcall.status,
	ret);

	orangefs_readdir_index_put(buffer_index);

	if (ret == -EAGAIN && op_state_purged(new_op)) {
	/* Client-core indices are invalid after it restarted. */
	gossip_debug(GOSSIP_DIR_DEBUG,
	"%s: Getting new buffer_index for retry of readdir..\n",
	__func__);
	goto get_new_buffer_index;
	}

	if (ret == -EIO && op_state_purged(new_op)) {
	gossip_err("%s: Client is down. Aborting readdir call.\n",
	__func__);
	goto out_free_op;
	}

	if (ret < 0 \|\| new_op->downcall.status != 0) {
	gossip_debug(GOSSIP_DIR_DEBUG,
	"Readdir request failed. Status:%d\n",
	new_op->downcall.status);
	if (ret >= 0)
	ret = new_op->downcall.status;
	goto out_free_op;
	}

	dents_buf = new_op->downcall.trailer_buf;
	if (dents_buf == NULL) {
	gossip_err("Invalid NULL buffer in readdir response\n");
	ret = -ENOMEM;
	goto out_free_op;
	}

	bytes_decoded = decode_dirents(dents_buf, new_op->downcall.trailer_size,
	&readdir_response);
	if (bytes_decoded < 0) {
	ret = bytes_decoded;
	gossip_err("Could not decode readdir from buffer %d\n", ret);
	goto out_vfree;
	}

	if (bytes_decoded != new_op->downcall.trailer_size) {
	gossip_err("orangefs_readdir: # bytes decoded (%ld) "
	"!= trailer size (%ld)\n",
	bytes_decoded,
	(long)new_op->downcall.trailer_size);
	ret = -EINVAL;
	goto out_destroy_handle;
	}

	/*
	* orangefs doesn't actually store dot and dot-dot, but
	* we need to have them represented.
	*/
	if (pos == 0) {
	ino = get_ino_from_khandle(dentry->d_inode);
	gossip_debug(GOSSIP_DIR_DEBUG,
	"%s: calling dir_emit of \".\" with pos = %llu\n",
	__func__,
	llu(pos));
	ret = dir_emit(ctx, ".", 1, ino, DT_DIR);
	pos += 1;
	}

	if (pos == 1) {
	ino = get_parent_ino_from_dentry(dentry);
	gossip_debug(GOSSIP_DIR_DEBUG,
	"%s: calling dir_emit of \"..\" with pos = %llu\n",
	__func__,
	llu(pos));
	ret = dir_emit(ctx, "..", 2, ino, DT_DIR);
	pos += 1;
	}

	/*
	* we stored ORANGEFS_ITERATE_NEXT in ctx->pos last time around
	* to prevent "finding" dot and dot-dot on any iteration
	* other than the first.
	*/
	if (ctx->pos == ORANGEFS_ITERATE_NEXT)
	ctx->pos = 0;

	gossip_debug(GOSSIP_DIR_DEBUG,
	"%s: dirent_outcount:%d:\n",
	__func__,
	readdir_response.orangefs_dirent_outcount);
	for (i = ctx->pos;
	i < readdir_response.orangefs_dirent_outcount;
	i++) {
	len = readdir_response.dirent_array[i].d_length;
	current_entry = readdir_response.dirent_array[i].d_name;
	current_ino = orangefs_khandle_to_ino(
	&readdir_response.dirent_array[i].khandle);

	gossip_debug(GOSSIP_DIR_DEBUG,
	"calling dir_emit for %s with len %d"
	", ctx->pos %ld\n",
	current_entry,
	len,
	(unsigned long)ctx->pos);
	/*
	* type is unknown. We don't return object type
	* in the dirent_array. This leaves getdents
	* clueless about type.
	*/
	ret =
	dir_emit(ctx, current_entry, len, current_ino, DT_UNKNOWN);
	if (!ret)
	break;
	ctx->pos++;
	gossip_debug(GOSSIP_DIR_DEBUG,
	"%s: ctx->pos:%lld\n",
	__func__,
	lld(ctx->pos));

	}

	/*
	* we ran all the way through the last batch, set up for
	* getting another batch...
	*/
	if (ret) {
	*ptoken = readdir_response.token;
	ctx->pos = ORANGEFS_ITERATE_NEXT;
	}

	/*
	* Did we hit the end of the directory?
	*/
	if (readdir_response.token == ORANGEFS_READDIR_END) {
	gossip_debug(GOSSIP_DIR_DEBUG,
	"End of dir detected; setting ctx->pos to ORANGEFS_READDIR_END.\n");
	ctx->pos = ORANGEFS_READDIR_END;
	}

	out_destroy_handle:
	/* kfree(NULL) is safe */
	kfree(readdir_response.dirent_array);
	out_vfree:
	gossip_debug(GOSSIP_DIR_DEBUG, "vfree %p\n", dents_buf);
	vfree(dents_buf);
	out_free_op:
	op_release(new_op);
	gossip_debug(GOSSIP_DIR_DEBUG, "orangefs_readdir returning %d\n", ret);
	return ret;
	}

	static int orangefs_dir_open(struct inode inode, struct file file)
	{
	__u64 *ptoken;

	file->private_data = kmalloc(sizeof(__u64), GFP_KERNEL);
	if (!file->private_data)
	return -ENOMEM;

	ptoken = file->private_data;
	*ptoken = ORANGEFS_READDIR_START;
	return 0;
	}

	static int orangefs_dir_release(struct inode inode, struct file file)
	{
	orangefs_flush_inode(inode);
	kfree(file->private_data);
	return 0;
	}

	/** ORANGEFS implementation of VFS directory operations */
	const struct file_operations orangefs_dir_operations = {
	.read = generic_read_dir,
	.iterate = orangefs_readdir,
	.open = orangefs_dir_open,
	.release = orangefs_dir_release,
	};