License cleanup: add SPDX GPL-2.0 license identifier to files with no license

Many source files in the tree are missing licensing information, which
makes it harder for compliance tools to determine the correct license.

By default all files without license information are under the default
license of the kernel, which is GPL version 2.

Update the files which contain no license information with the 'GPL-2.0'
SPDX license identifier.  The SPDX identifier is a legally binding
shorthand, which can be used instead of the full boiler plate text.

This patch is based on work done by Thomas Gleixner and Kate Stewart and
Philippe Ombredanne.

How this work was done:

Patches were generated and checked against linux-4.14-rc6 for a subset of
the use cases:
 - file had no licensing information it it.
 - file was a */uapi/* one with no licensing information in it,
 - file was a */uapi/* one with existing licensing information,

Further patches will be generated in subsequent months to fix up cases
where non-standard license headers were used, and references to license
had to be inferred by heuristics based on keywords.

The analysis to determine which SPDX License Identifier to be applied to
a file was done in a spreadsheet of side by side results from of the
output of two independent scanners (ScanCode & Windriver) producing SPDX
tag:value files created by Philippe Ombredanne.  Philippe prepared the
base worksheet, and did an initial spot review of a few 1000 files.

The 4.13 kernel was the starting point of the analysis with 60,537 files
assessed.  Kate Stewart did a file by file comparison of the scanner
results in the spreadsheet to determine which SPDX license identifier(s)
to be applied to the file. She confirmed any determination that was not
immediately clear with lawyers working with the Linux Foundation.

Criteria used to select files for SPDX license identifier tagging was:
 - Files considered eligible had to be source code files.
 - Make and config files were included as candidates if they contained >5
   lines of source
 - File already had some variant of a license header in it (even if <5
   lines).

All documentation files were explicitly excluded.

The following heuristics were used to determine which SPDX license
identifiers to apply.

 - when both scanners couldn't find any license traces, file was
   considered to have no license information in it, and the top level
   COPYING file license applied.

   For non */uapi/* files that summary was:

   SPDX license identifier                            # files
   ---------------------------------------------------|-------
   GPL-2.0                                              11139

   and resulted in the first patch in this series.

   If that file was a */uapi/* path one, it was "GPL-2.0 WITH
   Linux-syscall-note" otherwise it was "GPL-2.0".  Results of that was:

   SPDX license identifier                            # files
   ---------------------------------------------------|-------
   GPL-2.0 WITH Linux-syscall-note                        930

   and resulted in the second patch in this series.

 - if a file had some form of licensing information in it, and was one
   of the */uapi/* ones, it was denoted with the Linux-syscall-note if
   any GPL family license was found in the file or had no licensing in
   it (per prior point).  Results summary:

   SPDX license identifier                            # files
   ---------------------------------------------------|------
   GPL-2.0 WITH Linux-syscall-note                       270
   GPL-2.0+ WITH Linux-syscall-note                      169
   ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause)    21
   ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause)    17
   LGPL-2.1+ WITH Linux-syscall-note                      15
   GPL-1.0+ WITH Linux-syscall-note                       14
   ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause)    5
   LGPL-2.0+ WITH Linux-syscall-note                       4
   LGPL-2.1 WITH Linux-syscall-note                        3
   ((GPL-2.0 WITH Linux-syscall-note) OR MIT)              3
   ((GPL-2.0 WITH Linux-syscall-note) AND MIT)             1

   and that resulted in the third patch in this series.

 - when the two scanners agreed on the detected license(s), that became
   the concluded license(s).

 - when there was disagreement between the two scanners (one detected a
   license but the other didn't, or they both detected different
   licenses) a manual inspection of the file occurred.

 - In most cases a manual inspection of the information in the file
   resulted in a clear resolution of the license that should apply (and
   which scanner probably needed to revisit its heuristics).

 - When it was not immediately clear, the license identifier was
   confirmed with lawyers working with the Linux Foundation.

 - If there was any question as to the appropriate license identifier,
   the file was flagged for further research and to be revisited later
   in time.

In total, over 70 hours of logged manual review was done on the
spreadsheet to determine the SPDX license identifiers to apply to the
source files by Kate, Philippe, Thomas and, in some cases, confirmation
by lawyers working with the Linux Foundation.

Kate also obtained a third independent scan of the 4.13 code base from
FOSSology, and compared selected files where the other two scanners
disagreed against that SPDX file, to see if there was new insights.  The
Windriver scanner is based on an older version of FOSSology in part, so
they are related.

Thomas did random spot checks in about 500 files from the spreadsheets
for the uapi headers and agreed with SPDX license identifier in the
files he inspected. For the non-uapi files Thomas did random spot checks
in about 15000 files.

In initial set of patches against 4.14-rc6, 3 files were found to have
copy/paste license identifier errors, and have been fixed to reflect the
correct identifier.

Additionally Philippe spent 10 hours this week doing a detailed manual
inspection and review of the 12,461 patched files from the initial patch
version early this week with:
 - a full scancode scan run, collecting the matched texts, detected
   license ids and scores
 - reviewing anything where there was a license detected (about 500+
   files) to ensure that the applied SPDX license was correct
 - reviewing anything where there was no detection but the patch license
   was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied
   SPDX license was correct

This produced a worksheet with 20 files needing minor correction.  This
worksheet was then exported into 3 different .csv files for the
different types of files to be modified.

These .csv files were then reviewed by Greg.  Thomas wrote a script to
parse the csv files and add the proper SPDX tag to the file, in the
format that the file expected.  This script was further refined by Greg
based on the output to detect more types of files automatically and to
distinguish between header and source .c files (which need different
comment types.)  Finally Greg ran the script using the .csv files to
generate the patches.

Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/drivers/target/Makefile b/drivers/target/Makefile
index e619c02..4563474 100644
--- a/drivers/target/Makefile
+++ b/drivers/target/Makefile
@@ -1,3 +1,4 @@
+# SPDX-License-Identifier: GPL-2.0
 
 target_core_mod-y		:= target_core_configfs.o \
 				   target_core_device.o \
diff --git a/drivers/target/iscsi/Makefile b/drivers/target/iscsi/Makefile
index 0f18295..8c9ae96 100644
--- a/drivers/target/iscsi/Makefile
+++ b/drivers/target/iscsi/Makefile
@@ -1,3 +1,4 @@
+# SPDX-License-Identifier: GPL-2.0
 iscsi_target_mod-y +=		iscsi_target_parameters.o \
 				iscsi_target_seq_pdu_list.o \
 				iscsi_target_auth.o \
diff --git a/drivers/target/iscsi/cxgbit/Makefile b/drivers/target/iscsi/cxgbit/Makefile
index 4893ec2..d16aaae 100644
--- a/drivers/target/iscsi/cxgbit/Makefile
+++ b/drivers/target/iscsi/cxgbit/Makefile
@@ -1,3 +1,4 @@
+# SPDX-License-Identifier: GPL-2.0
 ccflags-y := -Idrivers/net/ethernet/chelsio/cxgb4
 ccflags-y += -Idrivers/net/ethernet/chelsio/libcxgb
 ccflags-y += -Idrivers/target/iscsi
diff --git a/drivers/target/iscsi/iscsi_target.h b/drivers/target/iscsi/iscsi_target.h
index e0db2ce..42de184 100644
--- a/drivers/target/iscsi/iscsi_target.h
+++ b/drivers/target/iscsi/iscsi_target.h
@@ -1,3 +1,4 @@
+/* SPDX-License-Identifier: GPL-2.0 */
 #ifndef ISCSI_TARGET_H
 #define ISCSI_TARGET_H
 
diff --git a/drivers/target/iscsi/iscsi_target_auth.h b/drivers/target/iscsi/iscsi_target_auth.h
index 1b91c13..d5600ac 100644
--- a/drivers/target/iscsi/iscsi_target_auth.h
+++ b/drivers/target/iscsi/iscsi_target_auth.h
@@ -1,3 +1,4 @@
+/* SPDX-License-Identifier: GPL-2.0 */
 #ifndef _ISCSI_CHAP_H_
 #define _ISCSI_CHAP_H_
 
diff --git a/drivers/target/iscsi/iscsi_target_datain_values.h b/drivers/target/iscsi/iscsi_target_datain_values.h
index 16edeee..a420fbd 100644
--- a/drivers/target/iscsi/iscsi_target_datain_values.h
+++ b/drivers/target/iscsi/iscsi_target_datain_values.h
@@ -1,3 +1,4 @@
+/* SPDX-License-Identifier: GPL-2.0 */
 #ifndef ISCSI_TARGET_DATAIN_VALUES_H
 #define ISCSI_TARGET_DATAIN_VALUES_H
 
diff --git a/drivers/target/iscsi/iscsi_target_device.h b/drivers/target/iscsi/iscsi_target_device.h
index 06dbff5..ab2166f 100644
--- a/drivers/target/iscsi/iscsi_target_device.h
+++ b/drivers/target/iscsi/iscsi_target_device.h
@@ -1,3 +1,4 @@
+/* SPDX-License-Identifier: GPL-2.0 */
 #ifndef ISCSI_TARGET_DEVICE_H
 #define ISCSI_TARGET_DEVICE_H
 
diff --git a/drivers/target/iscsi/iscsi_target_erl0.h b/drivers/target/iscsi/iscsi_target_erl0.h
index 3822d9c..3393407 100644
--- a/drivers/target/iscsi/iscsi_target_erl0.h
+++ b/drivers/target/iscsi/iscsi_target_erl0.h
@@ -1,3 +1,4 @@
+/* SPDX-License-Identifier: GPL-2.0 */
 #ifndef ISCSI_TARGET_ERL0_H
 #define ISCSI_TARGET_ERL0_H
 
diff --git a/drivers/target/iscsi/iscsi_target_erl1.h b/drivers/target/iscsi/iscsi_target_erl1.h
index 54d36bd..5f66b26 100644
--- a/drivers/target/iscsi/iscsi_target_erl1.h
+++ b/drivers/target/iscsi/iscsi_target_erl1.h
@@ -1,3 +1,4 @@
+/* SPDX-License-Identifier: GPL-2.0 */
 #ifndef ISCSI_TARGET_ERL1_H
 #define ISCSI_TARGET_ERL1_H
 
diff --git a/drivers/target/iscsi/iscsi_target_erl2.h b/drivers/target/iscsi/iscsi_target_erl2.h
index 634d01e..93e180d 100644
--- a/drivers/target/iscsi/iscsi_target_erl2.h
+++ b/drivers/target/iscsi/iscsi_target_erl2.h
@@ -1,3 +1,4 @@
+/* SPDX-License-Identifier: GPL-2.0 */
 #ifndef ISCSI_TARGET_ERL2_H
 #define ISCSI_TARGET_ERL2_H
 
diff --git a/drivers/target/iscsi/iscsi_target_login.h b/drivers/target/iscsi/iscsi_target_login.h
index 0e1fd6c..c2495e0 100644
--- a/drivers/target/iscsi/iscsi_target_login.h
+++ b/drivers/target/iscsi/iscsi_target_login.h
@@ -1,3 +1,4 @@
+/* SPDX-License-Identifier: GPL-2.0 */
 #ifndef ISCSI_TARGET_LOGIN_H
 #define ISCSI_TARGET_LOGIN_H
 
diff --git a/drivers/target/iscsi/iscsi_target_nego.h b/drivers/target/iscsi/iscsi_target_nego.h
index 53438bf..835e1b7 100644
--- a/drivers/target/iscsi/iscsi_target_nego.h
+++ b/drivers/target/iscsi/iscsi_target_nego.h
@@ -1,3 +1,4 @@
+/* SPDX-License-Identifier: GPL-2.0 */
 #ifndef ISCSI_TARGET_NEGO_H
 #define ISCSI_TARGET_NEGO_H
 
diff --git a/drivers/target/iscsi/iscsi_target_nodeattrib.h b/drivers/target/iscsi/iscsi_target_nodeattrib.h
index 79cdf06..ce074cb 100644
--- a/drivers/target/iscsi/iscsi_target_nodeattrib.h
+++ b/drivers/target/iscsi/iscsi_target_nodeattrib.h
@@ -1,3 +1,4 @@
+/* SPDX-License-Identifier: GPL-2.0 */
 #ifndef ISCSI_TARGET_NODEATTRIB_H
 #define ISCSI_TARGET_NODEATTRIB_H
 
diff --git a/drivers/target/iscsi/iscsi_target_parameters.h b/drivers/target/iscsi/iscsi_target_parameters.h
index c47b73f..daf47f3 100644
--- a/drivers/target/iscsi/iscsi_target_parameters.h
+++ b/drivers/target/iscsi/iscsi_target_parameters.h
@@ -1,3 +1,4 @@
+/* SPDX-License-Identifier: GPL-2.0 */
 #ifndef ISCSI_PARAMETERS_H
 #define ISCSI_PARAMETERS_H
 
diff --git a/drivers/target/iscsi/iscsi_target_seq_pdu_list.h b/drivers/target/iscsi/iscsi_target_seq_pdu_list.h
index be12343..5a09070 100644
--- a/drivers/target/iscsi/iscsi_target_seq_pdu_list.h
+++ b/drivers/target/iscsi/iscsi_target_seq_pdu_list.h
@@ -1,3 +1,4 @@
+/* SPDX-License-Identifier: GPL-2.0 */
 #ifndef ISCSI_SEQ_AND_PDU_LIST_H
 #define ISCSI_SEQ_AND_PDU_LIST_H
 
diff --git a/drivers/target/iscsi/iscsi_target_tmr.h b/drivers/target/iscsi/iscsi_target_tmr.h
index 64cc5c0..301f093 100644
--- a/drivers/target/iscsi/iscsi_target_tmr.h
+++ b/drivers/target/iscsi/iscsi_target_tmr.h
@@ -1,3 +1,4 @@
+/* SPDX-License-Identifier: GPL-2.0 */
 #ifndef ISCSI_TARGET_TMR_H
 #define ISCSI_TARGET_TMR_H
 
diff --git a/drivers/target/iscsi/iscsi_target_tpg.h b/drivers/target/iscsi/iscsi_target_tpg.h
index 59fd3ca..88576f5 100644
--- a/drivers/target/iscsi/iscsi_target_tpg.h
+++ b/drivers/target/iscsi/iscsi_target_tpg.h
@@ -1,3 +1,4 @@
+/* SPDX-License-Identifier: GPL-2.0 */
 #ifndef ISCSI_TARGET_TPG_H
 #define ISCSI_TARGET_TPG_H
 
diff --git a/drivers/target/iscsi/iscsi_target_transport.c b/drivers/target/iscsi/iscsi_target_transport.c
index c4eb141..0369405 100644
--- a/drivers/target/iscsi/iscsi_target_transport.c
+++ b/drivers/target/iscsi/iscsi_target_transport.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
 #include <linux/spinlock.h>
 #include <linux/list.h>
 #include <linux/module.h>
diff --git a/drivers/target/iscsi/iscsi_target_util.h b/drivers/target/iscsi/iscsi_target_util.h
index 4251605..5e053d6 100644
--- a/drivers/target/iscsi/iscsi_target_util.h
+++ b/drivers/target/iscsi/iscsi_target_util.h
@@ -1,3 +1,4 @@
+/* SPDX-License-Identifier: GPL-2.0 */
 #ifndef ISCSI_TARGET_UTIL_H
 #define ISCSI_TARGET_UTIL_H
 
diff --git a/drivers/target/loopback/tcm_loop.h b/drivers/target/loopback/tcm_loop.h
index 3acc43c..d311090 100644
--- a/drivers/target/loopback/tcm_loop.h
+++ b/drivers/target/loopback/tcm_loop.h
@@ -1,3 +1,4 @@
+/* SPDX-License-Identifier: GPL-2.0 */
 #include <linux/types.h>
 #include <linux/device.h>
 #include <target/target_core_base.h> /* struct se_cmd */
diff --git a/drivers/target/sbp/sbp_target.h b/drivers/target/sbp/sbp_target.h
index 73bcb12..1d101ac 100644
--- a/drivers/target/sbp/sbp_target.h
+++ b/drivers/target/sbp/sbp_target.h
@@ -1,3 +1,4 @@
+/* SPDX-License-Identifier: GPL-2.0 */
 #ifndef _SBP_BASE_H
 #define _SBP_BASE_H
 
diff --git a/drivers/target/target_core_alua.h b/drivers/target/target_core_alua.h
index c69c11b..1902cb5 100644
--- a/drivers/target/target_core_alua.h
+++ b/drivers/target/target_core_alua.h
@@ -1,3 +1,4 @@
+/* SPDX-License-Identifier: GPL-2.0 */
 #ifndef TARGET_CORE_ALUA_H
 #define TARGET_CORE_ALUA_H
 
diff --git a/drivers/target/target_core_file.h b/drivers/target/target_core_file.h
index 526595a..53be5ff 100644
--- a/drivers/target/target_core_file.h
+++ b/drivers/target/target_core_file.h
@@ -1,3 +1,4 @@
+/* SPDX-License-Identifier: GPL-2.0 */
 #ifndef TARGET_CORE_FILE_H
 #define TARGET_CORE_FILE_H
 
diff --git a/drivers/target/target_core_iblock.h b/drivers/target/target_core_iblock.h
index f2a5797..b4aeb25 100644
--- a/drivers/target/target_core_iblock.h
+++ b/drivers/target/target_core_iblock.h
@@ -1,3 +1,4 @@
+/* SPDX-License-Identifier: GPL-2.0 */
 #ifndef TARGET_CORE_IBLOCK_H
 #define TARGET_CORE_IBLOCK_H
 
diff --git a/drivers/target/target_core_internal.h b/drivers/target/target_core_internal.h
index f30e8ac..18e3eb1 100644
--- a/drivers/target/target_core_internal.h
+++ b/drivers/target/target_core_internal.h
@@ -1,3 +1,4 @@
+/* SPDX-License-Identifier: GPL-2.0 */
 #ifndef TARGET_CORE_INTERNAL_H
 #define TARGET_CORE_INTERNAL_H
 
diff --git a/drivers/target/target_core_pr.h b/drivers/target/target_core_pr.h
index 772f914..198fad5 100644
--- a/drivers/target/target_core_pr.h
+++ b/drivers/target/target_core_pr.h
@@ -1,3 +1,4 @@
+/* SPDX-License-Identifier: GPL-2.0 */
 #ifndef TARGET_CORE_PR_H
 #define TARGET_CORE_PR_H
 
diff --git a/drivers/target/target_core_pscsi.h b/drivers/target/target_core_pscsi.h
index b86fb0e..e8458b5 100644
--- a/drivers/target/target_core_pscsi.h
+++ b/drivers/target/target_core_pscsi.h
@@ -1,3 +1,4 @@
+/* SPDX-License-Identifier: GPL-2.0 */
 #ifndef TARGET_CORE_PSCSI_H
 #define TARGET_CORE_PSCSI_H
 
diff --git a/drivers/target/target_core_rd.h b/drivers/target/target_core_rd.h
index 91fc1a3..8b88f9b 100644
--- a/drivers/target/target_core_rd.h
+++ b/drivers/target/target_core_rd.h
@@ -1,3 +1,4 @@
+/* SPDX-License-Identifier: GPL-2.0 */
 #ifndef TARGET_CORE_RD_H
 #define TARGET_CORE_RD_H
 
diff --git a/drivers/target/target_core_ua.h b/drivers/target/target_core_ua.h
index 9740285..b0f4205 100644
--- a/drivers/target/target_core_ua.h
+++ b/drivers/target/target_core_ua.h
@@ -1,3 +1,4 @@
+/* SPDX-License-Identifier: GPL-2.0 */
 #ifndef TARGET_CORE_UA_H
 #define TARGET_CORE_UA_H
 
diff --git a/drivers/target/target_core_xcopy.h b/drivers/target/target_core_xcopy.h
index 7c0b105..26ba4c3 100644
--- a/drivers/target/target_core_xcopy.h
+++ b/drivers/target/target_core_xcopy.h
@@ -1,3 +1,4 @@
+/* SPDX-License-Identifier: GPL-2.0 */
 #include <target/target_core_base.h>
 
 #define XCOPY_HDR_LEN			16
diff --git a/drivers/target/tcm_fc/Makefile b/drivers/target/tcm_fc/Makefile
index 20b14bb..a7d1593 100644
--- a/drivers/target/tcm_fc/Makefile
+++ b/drivers/target/tcm_fc/Makefile
@@ -1,3 +1,4 @@
+# SPDX-License-Identifier: GPL-2.0
 tcm_fc-y +=		tfc_cmd.o \
 			tfc_conf.o \
 			tfc_io.o \