Update memshr API and tools

This patch is the folded version of API updates, along with the associated tool
changes to ensure that the build is always consistent.

API updates:
- The source domain in the sharing calls is no longer assumed to be dom0.
- Previously, the mem sharing code would return an opaque handle to index
  shared pages (and nominees) in its global hash table.  By removing the hash
  table, the handle becomes a version, to avoid sharing a stale version of a
  page. Thus, libxc wrappers and tools need to be updated to recall the share
  functions with the information needed to fetch the page (which they readily
  have).

Tool updates:
The only (in-tree, that we know of) consumer of the mem sharing API is the
memshr tool. This is updated to use the new API.

Signed-off-by: Andres Lagar-Cavilla <andres@lagarcavilla.org>
Signed-off-by: Adin Scannell <adin@scannell.ca>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
Committed-by: Tim Deegan <tim@xen.org>

2 files changed, 4 insertions, 4 deletions

diff --git a/tools/blktap2/drivers/tapdisk-vbd.c b/tools/blktap2/drivers/tapdisk-vbd.c
index 41425e2d83..c665f270cc 100644
--- a/tools/blktap2/drivers/tapdisk-vbd.c
+++ b/tools/blktap2/drivers/tapdisk-vbd.c
@@ -1218,14 +1218,14 @@ __tapdisk_vbd_complete_td_request(td_vbd_t *vbd, td_vbd_request_t *vreq,
 #ifdef MEMSHR
 		if (treq.op == TD_OP_READ
 		   && td_flag_test(image->flags, TD_OPEN_RDONLY)) {
-			uint64_t hnd  = treq.memshr_hnd;
+			share_tuple_t hnd = treq.memshr_hnd;
 			uint16_t uid  = image->memshr_id;
 			blkif_request_t *breq = &vreq->req;
 			uint64_t sec  = tapdisk_vbd_breq_get_sector(breq, treq);
 			int secs = breq->seg[treq.sidx].last_sect -
 			    breq->seg[treq.sidx].first_sect + 1;
 
-			if (hnd != 0)
+			if (hnd.handle != 0)
 				memshr_vbd_complete_ro_request(hnd, uid,
 								sec, secs);
 		}
@@ -1297,7 +1297,7 @@ __tapdisk_vbd_reissue_td_request(td_vbd_t *vbd,
 				/* Reset memshr handle. This'll prevent
 				 * memshr_vbd_complete_ro_request being called
 				 */
-				treq.memshr_hnd = 0;
+				treq.memshr_hnd.handle = 0;
 				td_complete_request(treq, 0);
 			} else
 				td_queue_read(parent, treq);
diff --git a/tools/blktap2/drivers/tapdisk.h b/tools/blktap2/drivers/tapdisk.h
index c7013d7ccd..66d508ee52 100644
--- a/tools/blktap2/drivers/tapdisk.h
+++ b/tools/blktap2/drivers/tapdisk.h
@@ -140,7 +140,7 @@ struct td_request {
 	void                        *private;
     
 #ifdef MEMSHR
-	uint64_t                     memshr_hnd;
+	share_tuple_t                memshr_hnd;
 #endif
 };