1 files changed, 400 insertions, 0 deletions
diff --git a/fs/orangefs/dir.c b/fs/orangefs/dir.c
new file mode 100644
index 000000000000..f30b6ecacdd1
--- /dev/null
+++ b/fs/orangefs/dir.c
@@ -0,0 +1,400 @@
+/*
+ * (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);
+	int buffer_full = 0;
+	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 %s (pos=%llu)\n",
+		     dentry->d_name.name, 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_slot;
+	}
+
+	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_slot;
+	}
+
+	dents_buf = new_op->downcall.trailer_buf;
+	if (dents_buf == NULL) {
+		gossip_err("Invalid NULL buffer in readdir response\n");
+		ret = -ENOMEM;
+		goto out_slot;
+	}
+
+	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 &&
+	    !buffer_full) {
+		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_slot:
+	orangefs_readdir_index_put(buffer_index);
+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,
+};