kclient: fix cap_snap flush to reference correct snap

The client was passing the snapid the data was to fall into
instead of the snap it _follows_ (which is now the mds tends
to look at things).  Use snapid-1 instead.  This fixes the
problem of files being written while the snapshot was taken
appearing as 0 bytes in the snapshot.

diff --git a/src/kernel/snap.c b/src/kernel/snap.c
index 03f9766c6e754cf0a7a18ea7890c85541c32565f..4d02987d08814b58d0f29856c1234a6f2ae7f116 100644 (file)
--- a/src/kernel/snap.c
+++ b/src/kernel/snap.c
@@ -319,7 +319,7 @@ void ceph_queue_cap_snap(struct ceph_inode_info *ci,
                kfree(capsnap);
        } else {
                igrab(inode);
-               capsnap->follows = snapc->seq;
+               capsnap->follows = snapc->seq - 1;
                capsnap->context = ceph_get_snap_context(snapc);
                capsnap->issued = __ceph_caps_issued(ci, NULL);
                /* dirty page count moved from _head to this cap_snap;
@@ -364,11 +364,15 @@ int __ceph_finish_cap_snap(struct ceph_inode_info *ci,
        capsnap->ctime = inode->i_ctime;
        capsnap->time_warp_seq = ci->i_time_warp_seq;
        if (capsnap->dirty) {
-               dout(10, "finish_cap_snap %p cap_snap %p snapc %p %llu "
+               dout(10, "finish_cap_snap %p cap_snap %p snapc %p %llu s=%llu"
                     "still has %d dirty pages\n", inode, capsnap,
-                    capsnap->context, capsnap->context->seq, capsnap->dirty);
+                    capsnap->context, capsnap->context->seq,
+                    capsnap->size, capsnap->dirty);
                return 0;
        }
+       dout(10, "finish_cap_snap %p cap_snap %p snapc %p %llu s=%llu clean\n",
+            inode, capsnap, capsnap->context,
+            capsnap->context->seq, capsnap->size);
        return 1;  /* caller should ceph_flush_snaps */
 }