commit d84d23d23457b1964537e3af11736b7054875b0f
Author: agr1 <agr1@48a34bb2-7106-0410-bc49-8aa7273d22a1>
Date:   Mon Sep 12 17:53:56 2011 +0000

    Fix send_data_rsp to handle sense data correctly
    
    Remove an overzealous BUG_ON and reorganize the code to cope with commands both
    with or without a tio.
    
    Signed-off-by: Arne Redlich <arne.redlich@googlemail.com>
    
    git-svn-id: https://iscsitarget.svn.sourceforge.net/svnroot/iscsitarget/trunk@462 48a34bb2-7106-0410-bc49-8aa7273d22a1

diff --git a/kernel/iscsi.c b/kernel/iscsi.c
index ee1d85e..423e4da 100644
--- a/kernel/iscsi.c
+++ b/kernel/iscsi.c
@@ -249,6 +249,9 @@ static void do_send_data_rsp(struct iscsi_cmnd *cmnd)
 	LIST_HEAD(send);
 
 	dprintk(D_GENERIC, "%p\n", cmnd);
+
+	BUG_ON(!cmnd->tio);
+
 	pdusize = conn->session->param.max_xmit_data_length;
 	expsize = cmnd_read_size(cmnd);
 	size = min(expsize, tio->size);
@@ -383,29 +386,23 @@ void send_scsi_rsp(struct iscsi_cmnd *req, void (*func)(struct iscsi_cmnd *))
 
 void send_data_rsp(struct iscsi_cmnd *req, void (*func)(struct iscsi_cmnd *))
 {
-	struct iscsi_cmnd *rsp;
-	struct iscsi_scsi_rsp_hdr *rsp_hdr;
-	u32 size;
-
 	func(req);
 
-	assert(req->tio);
-
-	size = min(req->tio->size, cmnd_read_size(req));
-
-	if (req->status == SAM_STAT_GOOD && size)
+	if (req->status == SAM_STAT_GOOD && req->tio && req->tio->size)
 		do_send_data_rsp(req);
 	else {
-		rsp = create_scsi_rsp(req);
-		rsp_hdr = (struct iscsi_scsi_rsp_hdr *) &rsp->pdu.bhs;
-		if ((size = cmnd_read_size(req)) > req->tio->size) {
+		struct iscsi_cmnd *rsp = create_scsi_rsp(req);
+		struct iscsi_scsi_rsp_hdr *rsp_hdr =
+			(struct iscsi_scsi_rsp_hdr *) &rsp->pdu.bhs;
+		const u32 exp_size = cmnd_read_size(req);
+		const u32 size = req->tio ? req->tio->size : 0;
+
+		if (exp_size > size) {
 			rsp_hdr->flags |= ISCSI_FLG_RESIDUAL_UNDERFLOW;
-			rsp_hdr->residual_count =
-					cpu_to_be32(size - req->tio->size);
-		} else if (size < req->tio->size) {
+			rsp_hdr->residual_count = cpu_to_be32(exp_size - size);
+		} else if (exp_size < size) {
 			rsp_hdr->flags |= ISCSI_FLG_RESIDUAL_OVERFLOW;
-			rsp_hdr->residual_count =
-					cpu_to_be32(req->tio->size - size);
+			rsp_hdr->residual_count = cpu_to_be32(size - exp_size);
 		}
 		iscsi_cmnd_init_write(rsp);
 	}