From: Andy Grover <agrover@redhat.com>
Date: Tue, 28 May 2013 23:55:21 +0000 (-0700)
Subject: target: Don't allocate pages for NULLIO devices
X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=670caa9f762647802a1b19749f127ac28949ca5a;p=linux-beck.git

target: Don't allocate pages for NULLIO devices

Signed-off-by: Andy Grover <agrover@redhat.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
---

diff --git a/drivers/target/target_core_rd.c b/drivers/target/target_core_rd.c
index 0921a64b5550..51127d15d5c5 100644
--- a/drivers/target/target_core_rd.c
+++ b/drivers/target/target_core_rd.c
@@ -139,6 +139,11 @@ static int rd_build_device_space(struct rd_dev *rd_dev)
 			rd_dev->rd_page_count);
 		return -EINVAL;
 	}
+
+	/* Don't need backing pages for NULLIO */
+	if (rd_dev->rd_flags & RDF_NULLIO)
+		return 0;
+
 	total_sg_needed = rd_dev->rd_page_count;
 
 	sg_tables = (total_sg_needed / max_sg_per_table) + 1;