target: Update QUEUE ALGORITHM MODIFIER control page default

[sfrench/cifs-2.6.git] / drivers / target / target_core_cdb.c

diff --git a/drivers/target/target_core_cdb.c b/drivers/target/target_core_cdb.c
index 9828300236619354f98a082e3670a8f9a280a2dc..145739bcf7528368b58f20b46d623a846097561e 100644 (file)
--- a/drivers/target/target_core_cdb.c
+++ b/drivers/target/target_core_cdb.c
@@ -774,6 +774,35 @@ target_modesense_control(struct se_device *dev, unsigned char *p)
        p[0] = 0x0a;
        p[1] = 0x0a;
        p[2] = 2;
+       /*
+        * From spc4r23, 7.4.7 Control mode page
+        *
+        * The QUEUE ALGORITHM MODIFIER field (see table 368) specifies
+        * restrictions on the algorithm used for reordering commands
+        * having the SIMPLE task attribute (see SAM-4).
+        *
+        *                    Table 368 -- QUEUE ALGORITHM MODIFIER field
+        *                         Code      Description
+        *                          0h       Restricted reordering
+        *                          1h       Unrestricted reordering allowed
+        *                          2h to 7h    Reserved
+        *                          8h to Fh    Vendor specific
+        *
+        * A value of zero in the QUEUE ALGORITHM MODIFIER field specifies that
+        * the device server shall order the processing sequence of commands
+        * having the SIMPLE task attribute such that data integrity is maintained
+        * for that I_T nexus (i.e., if the transmission of new SCSI transport protocol
+        * requests is halted at any time, the final value of all data observable
+        * on the medium shall be the same as if all the commands had been processed
+        * with the ORDERED task attribute).
+        *
+        * A value of one in the QUEUE ALGORITHM MODIFIER field specifies that the
+        * device server may reorder the processing sequence of commands having the
+        * SIMPLE task attribute in any manner. Any data integrity exposures related to
+        * command sequence order shall be explicitly handled by the application client
+        * through the selection of appropriate ommands and task attributes.
+        */
+       p[3] = (dev->se_sub_dev->se_dev_attrib.emulate_rest_reord == 1) ? 0x00 : 0x10;
        /*
         * From spc4r17, section 7.4.6 Control mode Page
         *