afs: Print the operation debug_id when logging an unexpected data version

Print the afs_operation debug_id when logging an unexpected change in the
data version.  This allows the logged message to be matched against
tracelines.
Signed-off-by: David Howells <dhowells@redhat.com>
Tested-By: Marc Dionne <marc.dionne@auristor.com>
cc: linux-afs@lists.infradead.org
cc: linux-cachefs@redhat.com
cc: linux-fsdevel@vger.kernel.org
Link: https://lore.kernel.org/r/160588528377.3465195.2206051235095182302.stgit@warthog.procyon.org.uk/ # rfc
Link: https://lore.kernel.org/r/161118146111.1232039.11398082422487058312.stgit@warthog.procyon.org.uk/ # rfc
Link: https://lore.kernel.org/r/161161042180.2537118.2471333561661033316.stgit@warthog.procyon.org.uk/ # v2
Link: https://lore.kernel.org/r/161340405772.1303470.3877167548944248214.stgit@warthog.procyon.org.uk/ # v3
Link: https://lore.kernel.org/r/161539549628.286939.15234870409714613954.stgit@warthog.procyon.org.uk/ # v4
Link: https://lore.kernel.org/r/161653805530.2770958.15120507632529970934.stgit@warthog.procyon.org.uk/ # v5
Link: https://lore.kernel.org/r/161789088290.6155.3494369629853673866.stgit@warthog.procyon.org.uk/ # v6

fs/afs/inode.c

@@ -214,11 +214,12 @@ static void afs_apply_status(struct afs_operation *op,
 
 	if (vp->dv_before + vp->dv_delta != status->data_version) {
 		if (test_bit(AFS_VNODE_CB_PROMISED, &vnode->flags))
-			pr_warn("kAFS: vnode modified {%llx:%llu} %llx->%llx %s\n",
+			pr_warn("kAFS: vnode modified {%llx:%llu} %llx->%llx %s (op=%x)\n",
 				vnode->fid.vid, vnode->fid.vnode,
 				(unsigned long long)vp->dv_before + vp->dv_delta,
 				(unsigned long long)status->data_version,
-				op->type ? op->type->name : "???");
+				op->type ? op->type->name : "???",
+				op->debug_id);
 
 		vnode->invalid_before = status->data_version;
 		if (vnode->status.type == AFS_FTYPE_DIR) {