Commit 9d7f0f13 authored by Yehuda Sadeh's avatar Yehuda Sadeh Committed by Sage Weil
Browse files

ceph: refactor messages data section allocation 



Signed-off-by: default avatarYehuda Sadeh <yehuda@hq.newdream.net>
parent 2450418c

fs/ceph/messenger.c

+39 −28
Original line number Diff line number Diff line
@@ -1315,7 +1315,7 @@ static int read_partial_message(struct ceph_connection *con) 
	struct ceph_msg *m = con->in_msg;

	void *p;

	int ret;

	int to, want, left;

	int to, left;

	unsigned front_len, middle_len, data_len, data_off;

	int datacrc = con->msgr->nocrc;

	int skip;
@@ -1351,6 +1351,7 @@ static int read_partial_message(struct ceph_connection *con) 
	data_len = le32_to_cpu(con->in_hdr.data_len);

	if (data_len > CEPH_MSG_MAX_DATA_LEN)

		return -EIO;

	data_off = le16_to_cpu(con->in_hdr.data_off);



	/* allocate message? */

	if (!con->in_msg) {
@@ -1375,7 +1376,10 @@ static int read_partial_message(struct ceph_connection *con) 
		m->front.iov_len = 0;    /* haven't read it yet */

		if (m->middle)

			m->middle->vec.iov_len = 0;

		memcpy(&m->hdr, &con->in_hdr, sizeof(con->in_hdr));



		con->in_msg_pos.page = 0;

		con->in_msg_pos.page_pos = data_off & ~PAGE_MASK;

		con->in_msg_pos.data_pos = 0;

	}



	/* front */
@@ -1393,31 +1397,6 @@ static int read_partial_message(struct ceph_connection *con) 
	}



	/* (page) data */

	data_off = le16_to_cpu(m->hdr.data_off);

	if (data_len == 0)

		goto no_data;



	if (m->nr_pages == 0) {

		con->in_msg_pos.page = 0;

		con->in_msg_pos.page_pos = data_off & ~PAGE_MASK;

		con->in_msg_pos.data_pos = 0;

		/* find pages for data payload */

		want = calc_pages_for(data_off & ~PAGE_MASK, data_len);

		ret = -1;

		mutex_unlock(&con->mutex);

		if (con->ops->prepare_pages)

			ret = con->ops->prepare_pages(con, m, want);

		mutex_lock(&con->mutex);

		if (ret < 0) {

			dout("%p prepare_pages failed, skipping payload\n", m);

			con->in_base_pos = -data_len - sizeof(m->footer);

			ceph_msg_put(con->in_msg);

			con->in_msg = NULL;

			con->in_tag = CEPH_MSGR_TAG_READY;

			return 0;

		}

		BUG_ON(m->nr_pages < want);

	}

	while (con->in_msg_pos.data_pos < data_len) {

		left = min((int)(data_len - con->in_msg_pos.data_pos),

			   (int)(PAGE_SIZE - con->in_msg_pos.page_pos));
@@ -1440,7 +1419,6 @@ static int read_partial_message(struct ceph_connection *con) 
		}

	}



no_data:

	/* footer */

	to = sizeof(m->hdr) + sizeof(m->footer);

	while (con->in_base_pos < to) {
@@ -2136,6 +2114,25 @@ static int ceph_alloc_middle(struct ceph_connection *con, struct ceph_msg *msg) 
	return 0;

}



static int ceph_alloc_data_section(struct ceph_connection *con, struct ceph_msg *msg)

{

	int ret;

	int want;

	int data_len = le32_to_cpu(msg->hdr.data_len);

	unsigned data_off = le16_to_cpu(msg->hdr.data_off);



	want = calc_pages_for(data_off & ~PAGE_MASK, data_len);

	ret = -1;

	mutex_unlock(&con->mutex);

	if (con->ops->prepare_pages)

		ret = con->ops->prepare_pages(con, msg, want);

	mutex_lock(&con->mutex);



	BUG_ON(msg->nr_pages < want);



	return ret;

}



/*

 * Generic message allocator, for incoming messages.

 */
@@ -2146,6 +2143,7 @@ static struct ceph_msg *ceph_alloc_msg(struct ceph_connection *con, 
	int type = le16_to_cpu(hdr->type);

	int front_len = le32_to_cpu(hdr->front_len);

	int middle_len = le32_to_cpu(hdr->middle_len);

	int data_len = le32_to_cpu(hdr->data_len);

	struct ceph_msg *msg = NULL;

	int ret;
@@ -2166,6 +2164,7 @@ static struct ceph_msg *ceph_alloc_msg(struct ceph_connection *con, 
			return ERR_PTR(-ENOMEM);

		}

	}

	memcpy(&msg->hdr, &con->in_hdr, sizeof(con->in_hdr));



	if (middle_len) {

		ret = ceph_alloc_middle(con, msg);
@@ -2175,6 +2174,18 @@ static struct ceph_msg *ceph_alloc_msg(struct ceph_connection *con, 
			return msg;

		}

	}



	if (data_len) {

		ret = ceph_alloc_data_section(con, msg);



		if (ret < 0) {

			*skip = 1;

			ceph_msg_put(msg);

			return NULL;

		}

	}





	return msg;

}