From: Nicholas Bellinger <nab@daterainc.com>
Date: Sun, 25 Aug 2013 23:10:57 +0000 (-0700)
Subject: target: Do memory allocation for bidi commands using target_alloc_sgl
X-Git-Tag: upstream/snapshot3+hdmi~4313^2~28
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=8cefe07b5e9c2b0212ad6809a219e4489807a746;p=platform%2Fadaptation%2Frenesas_rcar%2Frenesas_kernel.git

target: Do memory allocation for bidi commands using target_alloc_sgl

This patch updates transport_generic_new_cmd() to call target_alloc_sgl()
for SGL + page memory allocation for se_cmd->t_bidi_data_sg.

It also adds the special case for SCF_COMPARE_AND_WRITE to calculate a
different bidi_length based upon se_cmd->t_task_nolb.

Reported-by: Christoph Hellwig <hch@lst.de>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Hannes Reinecke <hare@suse.de>
Cc: Martin Petersen <martin.petersen@oracle.com>
Cc: Chris Mason <chris.mason@fusionio.com>
Cc: James Bottomley <JBottomley@Parallels.com>
Cc: Nicholas Bellinger <nab@linux-iscsi.org>
Signed-off-by: Nicholas Bellinger <nab@daterainc.com>
---

diff --git a/drivers/target/target_core_transport.c b/drivers/target/target_core_transport.c
index 607bc3d..c974e13 100644
--- a/drivers/target/target_core_transport.c
+++ b/drivers/target/target_core_transport.c
@@ -2149,6 +2149,23 @@ transport_generic_new_cmd(struct se_cmd *cmd)
 	    cmd->data_length) {
 		bool zero_flag = !(cmd->se_cmd_flags & SCF_SCSI_DATA_CDB);
 
+		if ((cmd->se_cmd_flags & SCF_BIDI) ||
+		    (cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE)) {
+			u32 bidi_length;
+
+			if (cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE)
+				bidi_length = cmd->t_task_nolb *
+					      cmd->se_dev->dev_attrib.block_size;
+			else
+				bidi_length = cmd->data_length;
+
+			ret = target_alloc_sgl(&cmd->t_bidi_data_sg,
+					       &cmd->t_bidi_data_nents,
+					       bidi_length, zero_flag);
+			if (ret < 0)
+				return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
+		}
+
 		ret = target_alloc_sgl(&cmd->t_data_sg, &cmd->t_data_nents,
 				       cmd->data_length, zero_flag);
 		if (ret < 0)