target: Move passthrough CDB parsing into a common function
Aside from whether they handle BIDI ops or not, parsing of the CDB by
kernel and user SCSI passthrough modules should be identical. Move this
into a new passthrough_parse_cdb() and call it from tcm-pscsi and tcm-user.
Reported-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Ilias Tsitsimpis <iliastsi@arrikto.com>
Signed-off-by: Andy Grover <agrover@redhat.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
diff --git a/drivers/target/target_core_device.c b/drivers/target/target_core_device.c
index 7faa6ae..56b20dc 100644
--- a/drivers/target/target_core_device.c
+++ b/drivers/target/target_core_device.c
@@ -33,6 +33,7 @@
#include <linux/kthread.h>
#include <linux/in.h>
#include <linux/export.h>
+#include <asm/unaligned.h>
#include <net/sock.h>
#include <net/tcp.h>
#include <scsi/scsi.h>
@@ -1707,3 +1708,76 @@
target_free_device(g_lun0_dev);
core_delete_hba(hba);
}
+
+/*
+ * Common CDB parsing for kernel and user passthrough.
+ */
+sense_reason_t
+passthrough_parse_cdb(struct se_cmd *cmd,
+ sense_reason_t (*exec_cmd)(struct se_cmd *cmd))
+{
+ unsigned char *cdb = cmd->t_task_cdb;
+
+ /*
+ * Clear a lun set in the cdb if the initiator talking to use spoke
+ * and old standards version, as we can't assume the underlying device
+ * won't choke up on it.
+ */
+ switch (cdb[0]) {
+ case READ_10: /* SBC - RDProtect */
+ case READ_12: /* SBC - RDProtect */
+ case READ_16: /* SBC - RDProtect */
+ case SEND_DIAGNOSTIC: /* SPC - SELF-TEST Code */
+ case VERIFY: /* SBC - VRProtect */
+ case VERIFY_16: /* SBC - VRProtect */
+ case WRITE_VERIFY: /* SBC - VRProtect */
+ case WRITE_VERIFY_12: /* SBC - VRProtect */
+ case MAINTENANCE_IN: /* SPC - Parameter Data Format for SA RTPG */
+ break;
+ default:
+ cdb[1] &= 0x1f; /* clear logical unit number */
+ break;
+ }
+
+ /*
+ * For REPORT LUNS we always need to emulate the response, for everything
+ * else, pass it up.
+ */
+ if (cdb[0] == REPORT_LUNS) {
+ cmd->execute_cmd = spc_emulate_report_luns;
+ return TCM_NO_SENSE;
+ }
+
+ /* Set DATA_CDB flag for ops that should have it */
+ switch (cdb[0]) {
+ case READ_6:
+ case READ_10:
+ case READ_12:
+ case READ_16:
+ case WRITE_6:
+ case WRITE_10:
+ case WRITE_12:
+ case WRITE_16:
+ case WRITE_VERIFY:
+ case WRITE_VERIFY_12:
+ case 0x8e: /* WRITE_VERIFY_16 */
+ case COMPARE_AND_WRITE:
+ case XDWRITEREAD_10:
+ cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
+ break;
+ case VARIABLE_LENGTH_CMD:
+ switch (get_unaligned_be16(&cdb[8])) {
+ case READ_32:
+ case WRITE_32:
+ case 0x0c: /* WRITE_VERIFY_32 */
+ case XDWRITEREAD_32:
+ cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
+ break;
+ }
+ }
+
+ cmd->execute_cmd = exec_cmd;
+
+ return TCM_NO_SENSE;
+}
+EXPORT_SYMBOL(passthrough_parse_cdb);