move memory_read_from_buffer() from fs.h to string.h

James Bottomley warns that inclusion of linux/fs.h in a low level
driver was always a danger signal.  This patch moves
memory_read_from_buffer() from fs.h to string.h and fixes includes in
existing memory_read_from_buffer() users.

Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Cc: James Bottomley <James.Bottomley@hansenpartnership.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Zhang Rui <rui.zhang@intel.com>
Cc: Bob Moore <robert.moore@intel.com>
Cc: Thomas Renninger <trenn@suse.de>
Cc: Len Brown <lenb@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/drivers/acpi/system.c b/drivers/acpi/system.c
index d8e3f15..91dec44 100644
--- a/drivers/acpi/system.c
+++ b/drivers/acpi/system.c
@@ -26,6 +26,7 @@
 #include <linux/proc_fs.h>
 #include <linux/seq_file.h>
 #include <linux/init.h>
+#include <linux/string.h>
 #include <asm/uaccess.h>
 
 #include <acpi/acpi_drivers.h>
diff --git a/drivers/zorro/zorro-sysfs.c b/drivers/zorro/zorro-sysfs.c
index 3da712c..5290552 100644
--- a/drivers/zorro/zorro-sysfs.c
+++ b/drivers/zorro/zorro-sysfs.c
@@ -15,7 +15,6 @@
 #include <linux/zorro.h>
 #include <linux/stat.h>
 #include <linux/string.h>
-#include <linux/fs.h>
 
 #include "zorro.h"
 
diff --git a/include/linux/fs.h b/include/linux/fs.h
index 9c2ac5c..ff54ae49 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -2006,8 +2006,6 @@
 
 extern ssize_t simple_read_from_buffer(void __user *to, size_t count,
 			loff_t *ppos, const void *from, size_t available);
-extern ssize_t memory_read_from_buffer(void *to, size_t count, loff_t *ppos,
-			const void *from, size_t available);
 
 #ifdef CONFIG_MIGRATION
 extern int buffer_migrate_page(struct address_space *,
diff --git a/include/linux/string.h b/include/linux/string.h
index efdc445..810d80d 100644
--- a/include/linux/string.h
+++ b/include/linux/string.h
@@ -111,5 +111,8 @@
 
 extern bool sysfs_streq(const char *s1, const char *s2);
 
+extern ssize_t memory_read_from_buffer(void *to, size_t count, loff_t *ppos,
+			const void *from, size_t available);
+
 #endif
 #endif /* _LINUX_STRING_H_ */