libceph: record byte count not page count

Record the byte count for an osd request rather than the page count.
The number of pages can always be derived from the byte count (and
alignment/offset) but the reverse is not true.

Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Josh Durgin <josh.durgin@inktank.com>

1 files changed, 29 insertions, 21 deletions

diff --git a/net/ceph/osd_client.c b/net/ceph/osd_client.c
index f9cf44504484..202af14dc6dc 100644
--- a/net/ceph/osd_client.c
+++ b/net/ceph/osd_client.c
@@ -107,6 +107,7 @@ static int calc_layout(struct ceph_file_layout *layout, u64 off, u64 *plen,
  */
 void ceph_osdc_release_request(struct kref *kref)
 {
+	int num_pages;
 	struct ceph_osd_request *req = container_of(kref,
 						    struct ceph_osd_request,
 						    r_kref);
@@ -124,13 +125,17 @@ void ceph_osdc_release_request(struct kref *kref)
 		ceph_msg_put(req->r_reply);
 
 	if (req->r_data_in.type == CEPH_OSD_DATA_TYPE_PAGES &&
-			req->r_data_in.own_pages)
-		ceph_release_page_vector(req->r_data_in.pages,
-					 req->r_data_in.num_pages);
+			req->r_data_in.own_pages) {
+		num_pages = calc_pages_for((u64)req->r_data_in.alignment,
+						(u64)req->r_data_in.length);
+		ceph_release_page_vector(req->r_data_in.pages, num_pages);
+	}
 	if (req->r_data_out.type == CEPH_OSD_DATA_TYPE_PAGES &&
-			req->r_data_out.own_pages)
-		ceph_release_page_vector(req->r_data_out.pages,
-					 req->r_data_out.num_pages);
+			req->r_data_out.own_pages) {
+		num_pages = calc_pages_for((u64)req->r_data_out.alignment,
+						(u64)req->r_data_out.length);
+		ceph_release_page_vector(req->r_data_out.pages, num_pages);
+	}
 
 	ceph_put_snap_context(req->r_snapc);
 	ceph_pagelist_release(&req->r_trail);
@@ -1753,8 +1758,12 @@ int ceph_osdc_start_request(struct ceph_osd_client *osdc,
 
 	osd_data = &req->r_data_out;
 	if (osd_data->type == CEPH_OSD_DATA_TYPE_PAGES) {
+		unsigned int page_count;
+
 		req->r_request->pages = osd_data->pages;
-		req->r_request->page_count = osd_data->num_pages;
+		page_count = calc_pages_for((u64)osd_data->alignment,
+						(u64)osd_data->length);
+		req->r_request->page_count = page_count;
 		req->r_request->page_alignment = osd_data->alignment;
 #ifdef CONFIG_BLOCK
 	} else if (osd_data->type == CEPH_OSD_DATA_TYPE_BIO) {
@@ -1967,11 +1976,11 @@ int ceph_osdc_readpages(struct ceph_osd_client *osdc,
 	osd_data = &req->r_data_in;
 	osd_data->type = CEPH_OSD_DATA_TYPE_PAGES;
 	osd_data->pages = pages;
-	osd_data->num_pages = calc_pages_for(page_align, *plen);
+	osd_data->length = *plen;
 	osd_data->alignment = page_align;
 
-	dout("readpages  final extent is %llu~%llu (%d pages align %d)\n",
-	     off, *plen, osd_data->num_pages, page_align);
+	dout("readpages  final extent is %llu~%llu (%llu bytes align %d)\n",
+	     off, *plen, osd_data->length, page_align);
 
 	rc = ceph_osdc_start_request(osdc, req, false);
 	if (!rc)
@@ -2013,10 +2022,9 @@ int ceph_osdc_writepages(struct ceph_osd_client *osdc, struct ceph_vino vino,
 	osd_data = &req->r_data_out;
 	osd_data->type = CEPH_OSD_DATA_TYPE_PAGES;
 	osd_data->pages = pages;
-	osd_data->num_pages = calc_pages_for(page_align, len);
+	osd_data->length = len;
 	osd_data->alignment = page_align;
-	dout("writepages %llu~%llu (%d pages)\n", off, len,
-		osd_data->num_pages);
+	dout("writepages %llu~%llu (%llu bytes)\n", off, len, osd_data->length);
 
 	rc = ceph_osdc_start_request(osdc, req, true);
 	if (!rc)
@@ -2112,23 +2120,23 @@ static struct ceph_msg *get_reply(struct ceph_connection *con,
 		struct ceph_osd_data *osd_data = &req->r_data_in;
 
 		if (osd_data->type == CEPH_OSD_DATA_TYPE_PAGES) {
-			int want;
+			unsigned int page_count;
 
-			want = calc_pages_for(osd_data->alignment, data_len);
 			if (osd_data->pages &&
-				unlikely(osd_data->num_pages < want)) {
+				unlikely(osd_data->length < data_len)) {
 
-				pr_warning("tid %lld reply has %d bytes %d "
-					"pages, we had only %d pages ready\n",
-					tid, data_len, want,
-					osd_data->num_pages);
+				pr_warning("tid %lld reply has %d bytes "
+					"we had only %llu bytes ready\n",
+					tid, data_len, osd_data->length);
 				*skip = 1;
 				ceph_msg_put(m);
 				m = NULL;
 				goto out;
 			}
+			page_count = calc_pages_for((u64)osd_data->alignment,
+							(u64)osd_data->length);
 			m->pages = osd_data->pages;
-			m->page_count = osd_data->num_pages;
+			m->page_count = page_count;
 			m->page_alignment = osd_data->alignment;
 #ifdef CONFIG_BLOCK
 		} else if (osd_data->type == CEPH_OSD_DATA_TYPE_BIO) {