[RFC PATCH 10/35] libceph: Convert notify_id_pages to a ceph_databuf

[David Howells <dhowells@redhat.com>]

Convert linger->notify_id_pages to a ceph_databuf

Signed-off-by: David Howells <dhowells@redhat.com>
cc: Viacheslav Dubeyko <slava@dubeyko.com>
cc: Alex Markuze <amarkuze@redhat.com>
cc: Ilya Dryomov <idryomov@gmail.com>
cc: ceph-devel@vger.kernel.org
cc: linux-fsdevel@vger.kernel.org
---
 include/linux/ceph/osd_client.h |  2 +-
 net/ceph/osd_client.c           | 24 +++++++++++++-----------
 2 files changed, 14 insertions(+), 12 deletions(-)

diff --git a/include/linux/ceph/osd_client.h b/include/linux/ceph/osd_client.h
index fe51c6ed23af..5ac4c0b4dfcd 100644
--- a/include/linux/ceph/osd_client.h
+++ b/include/linux/ceph/osd_client.h
@@ -349,7 +349,7 @@ struct ceph_osd_linger_request {
 	void *data;
 
 	struct ceph_pagelist *request_pl;
-	struct page **notify_id_pages;
+	struct ceph_databuf *notify_id_buf;
 
 	struct page ***preply_pages;
 	size_t *preply_len;
diff --git a/net/ceph/osd_client.c b/net/ceph/osd_client.c
index e1dbde4bf2b9..fc5c136e793d 100644
--- a/net/ceph/osd_client.c
+++ b/net/ceph/osd_client.c
@@ -2841,9 +2841,7 @@ static void linger_release(struct kref *kref)
 
 	if (lreq->request_pl)
 		ceph_pagelist_release(lreq->request_pl);
-	if (lreq->notify_id_pages)
-		ceph_release_page_vector(lreq->notify_id_pages, 1);
-
+	ceph_databuf_release(lreq->notify_id_buf);
 	ceph_osdc_put_request(lreq->reg_req);
 	ceph_osdc_put_request(lreq->ping_req);
 	target_destroy(&lreq->t);
@@ -3128,10 +3126,13 @@ static void linger_commit_cb(struct ceph_osd_request *req)
 	if (!lreq->is_watch) {
 		struct ceph_osd_data *osd_data =
 		    osd_req_op_data(req, 0, notify, response_data);
-		void *p = page_address(osd_data->pages[0]);
+		struct ceph_databuf *notify_id_buf = lreq->notify_id_buf;
+		void *p;
 
 		WARN_ON(req->r_ops[0].op != CEPH_OSD_OP_NOTIFY ||
-			osd_data->type != CEPH_OSD_DATA_TYPE_PAGES);
+			osd_data->type != CEPH_OSD_DATA_TYPE_DATABUF);
+
+		p = kmap_ceph_databuf_page(notify_id_buf, 0);
 
 		/* make note of the notify_id */
 		if (req->r_ops[0].outdata_len >= sizeof(u64)) {
@@ -3141,6 +3142,8 @@ static void linger_commit_cb(struct ceph_osd_request *req)
 		} else {
 			dout("lreq %p no notify_id\n", lreq);
 		}
+
+		kunmap_local(p);
 	}
 
 out:
@@ -3224,9 +3227,9 @@ static void send_linger(struct ceph_osd_linger_request *lreq)
 			refcount_inc(&lreq->request_pl->refcnt);
 			osd_req_op_notify_init(req, 0, lreq->linger_id,
 					       lreq->request_pl);
-			ceph_osd_data_pages_init(
+			ceph_osd_databuf_init(
 			    osd_req_op_data(req, 0, notify, response_data),
-			    lreq->notify_id_pages, PAGE_SIZE, 0, false, false);
+			    ceph_databuf_get(lreq->notify_id_buf));
 		}
 		dout("lreq %p register\n", lreq);
 		req->r_callback = linger_commit_cb;
@@ -5016,10 +5019,9 @@ int ceph_osdc_notify(struct ceph_osd_client *osdc,
 	}
 
 	/* for notify_id */
-	lreq->notify_id_pages = ceph_alloc_page_vector(1, GFP_NOIO);
-	if (IS_ERR(lreq->notify_id_pages)) {
-		ret = PTR_ERR(lreq->notify_id_pages);
-		lreq->notify_id_pages = NULL;
+	lreq->notify_id_buf = ceph_databuf_reply_alloc(1, PAGE_SIZE, GFP_NOIO);
+	if (!lreq->notify_id_buf) {
+		ret = -ENOMEM;
 		goto out_put_lreq;
 	}