target: Fix volume size misreporting for volumes > 2TB

commit 904f0bc4 upstream.

the target infrastructure fails to send the correct conventional size
to READ_CAPACITY that force a retry with READ_CAPACITY_16, which reads
the capacity for devices > 2TB.  Fix by adding the correct return to
trigger RC(16).
Reported-by: Ben Jarvis <bjarvismn@gmail.com>
Signed-off-by: Signed-off-by: Nicholas A. Bellinger <nab@linux-iscsi.org>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

drivers/target/target_core_cdb.c

@@ -667,7 +667,13 @@ target_emulate_readcapacity(struct se_cmd *cmd)
 {
 	struct se_device *dev = SE_DEV(cmd);
 	unsigned char *buf = cmd->t_task->t_task_buf;
-	u32 blocks = dev->transport->get_blocks(dev);
+	unsigned long long blocks_long = dev->transport->get_blocks(dev);
+	u32 blocks;
+
+	if (blocks_long >= 0x00000000ffffffff)
+		blocks = 0xffffffff;
+	else
+		blocks = (u32)blocks_long;
 
 	buf[0] = (blocks >> 24) & 0xff;
 	buf[1] = (blocks >> 16) & 0xff;