target: Minimize #include directives

Remove superfluous #include directives from the include/target/*.h
files. Add missing #include directives to other *.h and *.c files.
Use forward declarations for structures where possible. This
change reduces the build time for make M=drivers/target on my
laptop from 27.1s to 18.7s or by about 30%.

Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Bryant G. Ly <bryantly@linux.vnet.ibm.com>

6 files changed, 29 insertions, 17 deletions

diff --git a/include/target/iscsi/iscsi_target_core.h b/include/target/iscsi/iscsi_target_core.h
index 4ac24f5a3308..275581d483dd 100644
--- a/include/target/iscsi/iscsi_target_core.h
+++ b/include/target/iscsi/iscsi_target_core.h
@@ -1,12 +1,14 @@
 #ifndef ISCSI_TARGET_CORE_H
 #define ISCSI_TARGET_CORE_H
 
-#include <linux/in.h>
-#include <linux/configfs.h>
-#include <net/sock.h>
-#include <net/tcp.h>
-#include <scsi/iscsi_proto.h>
-#include <target/target_core_base.h>
+#include <linux/dma-direction.h>     /* enum dma_data_direction */
+#include <linux/list.h>              /* struct list_head */
+#include <linux/socket.h>            /* struct sockaddr_storage */
+#include <linux/types.h>             /* u8 */
+#include <scsi/iscsi_proto.h>        /* itt_t */
+#include <target/target_core_base.h> /* struct se_cmd */
+
+struct sock;
 
 #define ISCSIT_VERSION                  "v4.1.0"
 #define ISCSI_MAX_DATASN_MISSING_COUNT  16
diff --git a/include/target/iscsi/iscsi_target_stat.h b/include/target/iscsi/iscsi_target_stat.h
index e615bb485d0b..c27dd471656d 100644
--- a/include/target/iscsi/iscsi_target_stat.h
+++ b/include/target/iscsi/iscsi_target_stat.h
@@ -1,6 +1,10 @@
 #ifndef ISCSI_TARGET_STAT_H
 #define ISCSI_TARGET_STAT_H
 
+#include <linux/types.h>
+#include <linux/spinlock.h>
+#include <linux/socket.h>
+
 /*
  * For struct iscsi_tiqn->tiqn_wwn default groups
  */
diff --git a/include/target/iscsi/iscsi_transport.h b/include/target/iscsi/iscsi_transport.h
index 40ac7cd80150..1277e9ba0318 100644
--- a/include/target/iscsi/iscsi_transport.h
+++ b/include/target/iscsi/iscsi_transport.h
@@ -1,6 +1,6 @@
-#include <linux/module.h>
-#include <linux/list.h>
-#include "iscsi_target_core.h"
+#include "iscsi_target_core.h" /* struct iscsi_cmd */
+
+struct sockaddr_storage;
 
 struct iscsit_transport {
 #define ISCSIT_TRANSPORT_NAME   16
diff --git a/include/target/target_core_backend.h b/include/target/target_core_backend.h
index f6f3bc52c1ac..b54b98dc2d4a 100644
--- a/include/target/target_core_backend.h
+++ b/include/target/target_core_backend.h
@@ -1,8 +1,14 @@
 #ifndef TARGET_CORE_BACKEND_H
 #define TARGET_CORE_BACKEND_H
 
+#include <linux/types.h>
+#include <target/target_core_base.h>
+
 #define TRANSPORT_FLAG_PASSTHROUGH              1
 
+struct request_queue;
+struct scatterlist;
+
 struct target_backend_ops {
         char name[16];
         char inquiry_prod[16];
diff --git a/include/target/target_core_base.h b/include/target/target_core_base.h
index c2119008990a..ca8ec7218f39 100644
--- a/include/target/target_core_base.h
+++ b/include/target/target_core_base.h
@@ -1,14 +1,10 @@
 #ifndef TARGET_CORE_BASE_H
 #define TARGET_CORE_BASE_H
 
-#include <linux/in.h>
-#include <linux/configfs.h>
-#include <linux/dma-mapping.h>
-#include <linux/blkdev.h>
-#include <linux/percpu_ida.h>
-#include <linux/t10-pi.h>
-#include <net/sock.h>
-#include <net/tcp.h>
+#include <linux/configfs.h>      /* struct config_group */
+#include <linux/dma-direction.h> /* enum dma_data_direction */
+#include <linux/percpu_ida.h>    /* struct percpu_ida */
+#include <linux/semaphore.h>     /* struct semaphore */
 
 #define TARGET_CORE_VERSION             "v5.0"
 
diff --git a/include/target/target_core_fabric.h b/include/target/target_core_fabric.h
index 5cd6faa6e0d1..358041bad1da 100644
--- a/include/target/target_core_fabric.h
+++ b/include/target/target_core_fabric.h
@@ -1,6 +1,10 @@
 #ifndef TARGET_CORE_FABRIC_H
 #define TARGET_CORE_FABRIC_H
 
+#include <linux/configfs.h>
+#include <linux/types.h>
+#include <target/target_core_base.h>
+
 struct target_core_fabric_ops {
         struct module *module;
         const char *name;