1 files changed, 33 insertions, 4 deletions

diff --git a/fs/smb/client/file.c b/fs/smb/client/file.c
index f9b302cb8233..2d387485f05b 100644
--- a/fs/smb/client/file.c
+++ b/fs/smb/client/file.c
@@ -111,6 +111,7 @@ static void cifs_issue_write(struct netfs_io_subrequest *subreq)
 		goto fail;
 	}
 
+	wdata->actual_len = wdata->subreq.len;
 	rc = adjust_credits(wdata->server, wdata, cifs_trace_rw_credits_issue_write_adjust);
 	if (rc)
 		goto fail;
@@ -153,7 +154,7 @@ static bool cifs_clamp_length(struct netfs_io_subrequest *subreq)
 	struct cifs_io_request *req = container_of(subreq->rreq, struct cifs_io_request, rreq);
 	struct TCP_Server_Info *server = req->server;
 	struct cifs_sb_info *cifs_sb = CIFS_SB(rreq->inode->i_sb);
-	size_t rsize = 0;
+	size_t rsize;
 	int rc;
 
 	rdata->xid = get_xid();
@@ -166,8 +167,8 @@ static bool cifs_clamp_length(struct netfs_io_subrequest *subreq)
 						     cifs_sb->ctx);
 
 
-	rc = server->ops->wait_mtu_credits(server, cifs_sb->ctx->rsize, &rsize,
-					   &rdata->credits);
+	rc = server->ops->wait_mtu_credits(server, cifs_sb->ctx->rsize,
+					   &rsize, &rdata->credits);
 	if (rc) {
 		subreq->error = rc;
 		return false;
@@ -183,7 +184,8 @@ static bool cifs_clamp_length(struct netfs_io_subrequest *subreq)
 			      server->credits, server->in_flight, 0,
 			      cifs_trace_rw_credits_read_submit);
 
-	subreq->len = min_t(size_t, subreq->len, rsize);
+	subreq->len = umin(subreq->len, rsize);
+	rdata->actual_len = subreq->len;
 
 #ifdef CONFIG_CIFS_SMB_DIRECT
 	if (server->smbd_conn)
@@ -203,12 +205,39 @@ static void cifs_req_issue_read(struct netfs_io_subrequest *subreq)
 	struct netfs_io_request *rreq = subreq->rreq;
 	struct cifs_io_subrequest *rdata = container_of(subreq, struct cifs_io_subrequest, subreq);
 	struct cifs_io_request *req = container_of(subreq->rreq, struct cifs_io_request, rreq);
+	struct TCP_Server_Info *server = req->server;
+	struct cifs_sb_info *cifs_sb = CIFS_SB(rreq->inode->i_sb);
 	int rc = 0;
 
 	cifs_dbg(FYI, "%s: op=%08x[%x] mapping=%p len=%zu/%zu\n",
 		 __func__, rreq->debug_id, subreq->debug_index, rreq->mapping,
 		 subreq->transferred, subreq->len);
 
+	if (test_bit(NETFS_SREQ_RETRYING, &subreq->flags)) {
+		/*
+		 * As we're issuing a retry, we need to negotiate some new
+		 * credits otherwise the server may reject the op with
+		 * INVALID_PARAMETER.  Note, however, we may get back less
+		 * credit than we need to complete the op, in which case, we
+		 * shorten the op and rely on additional rounds of retry.
+		 */
+		size_t rsize = umin(subreq->len - subreq->transferred,
+				    cifs_sb->ctx->rsize);
+
+		rc = server->ops->wait_mtu_credits(server, rsize, &rdata->actual_len,
+						   &rdata->credits);
+		if (rc)
+			goto out;
+
+		rdata->credits.in_flight_check = 1;
+
+		trace_smb3_rw_credits(rdata->rreq->debug_id,
+				      rdata->subreq.debug_index,
+				      rdata->credits.value,
+				      server->credits, server->in_flight, 0,
+				      cifs_trace_rw_credits_read_resubmit);
+	}
+
 	if (req->cfile->invalidHandle) {
 		do {
 			rc = cifs_reopen_file(req->cfile, true);