scsi: core: Rename CONFIG_BLK_SCSI_REQUEST to CONFIG_SCSI_COMMON

CONFIG_BLK_SCSI_REQUEST is rather misnamed as it enables building a small
amount of code shared by the SCSI initiator, target, and consumers of the
scsi_request passthrough API.  Rename it and also allow building it as a
module.

[mkp: add module license]

Link: https://lore.kernel.org/r/20210724072033.1284840-20-hch@lst.de
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

Author: Christoph Hellwig

block/Kconfig

@@ -29,9 +29,6 @@ if BLOCK
 config BLK_RQ_ALLOC_TIME
 	bool
 
-config BLK_SCSI_REQUEST
-	bool
-
 config BLK_CGROUP_RWSTAT
 	bool
 

drivers/block/Kconfig

@@ -305,7 +305,7 @@ config CDROM_PKTCDVD
 	tristate "Packet writing on CD/DVD media (DEPRECATED)"
 	depends on !UML
 	select CDROM
-	select BLK_SCSI_REQUEST
+	select SCSI_COMMON
 	help
 	  Note: This driver is deprecated and will be removed from the
 	  kernel in the near future!

drivers/scsi/Kconfig

@@ -14,12 +14,15 @@ config RAID_ATTRS
 	help
 	  Provides RAID
 
+config SCSI_COMMON
+	tristate
+
 config SCSI
 	tristate "SCSI device support"
 	depends on BLOCK
 	select SCSI_DMA if HAS_DMA
 	select SG_POOL
-	select BLK_SCSI_REQUEST
+	select SCSI_COMMON
 	select BLK_DEV_BSG_COMMON if BLK_DEV_BSG
 	help
 	  If you want to use a SCSI hard disk, SCSI tape drive, SCSI CD-ROM or

drivers/scsi/Makefile

@@ -20,7 +20,7 @@ CFLAGS_aha152x.o =   -DAHA152X_STAT -DAUTOCONF
 obj-$(CONFIG_PCMCIA)		+= pcmcia/
 
 obj-$(CONFIG_SCSI)		+= scsi_mod.o
-obj-$(CONFIG_BLK_SCSI_REQUEST)	+= scsi_common.o
+obj-$(CONFIG_SCSI_COMMON)	+= scsi_common.o
 
 obj-$(CONFIG_RAID_ATTRS)	+= raid_class.o
 

drivers/scsi/scsi_common.c

@@ -7,9 +7,12 @@
 #include <linux/kernel.h>
 #include <linux/string.h>
 #include <linux/errno.h>
+#include <linux/module.h>
 #include <asm/unaligned.h>
 #include <scsi/scsi_common.h>
 
+MODULE_LICENSE("GPL v2");
+
 /* Command group 3 is reserved and should never be used.  */
 const unsigned char scsi_command_size_tbl[8] = {
 	6, 10, 10, 12, 16, 12, 10, 10

drivers/target/Kconfig

@@ -5,7 +5,7 @@ menuconfig TARGET_CORE
 	depends on BLOCK
 	select CONFIGFS_FS
 	select CRC_T10DIF
-	select BLK_SCSI_REQUEST
+	select SCSI_COMMON
 	select SGL_ALLOC
 	default n
 	help

fs/nfsd/Kconfig

@@ -109,7 +109,7 @@ config NFSD_SCSILAYOUT
 	depends on NFSD_V4 && BLOCK
 	select NFSD_PNFS
 	select EXPORTFS_BLOCK_OPS
-	select BLK_SCSI_REQUEST
+	select SCSI_COMMON
 	help
 	  This option enables support for the exporting pNFS SCSI layouts
 	  in the kernel's NFS server. The pNFS SCSI layout enables NFS