[PATCH] Add support for the sys_vmsplice syscall

sys_splice() moves data to/from pipes with a file input/output. sys_vmsplice()
moves data to a pipe, with the input being a user address range instead.

This uses an approach suggested by Linus, where we can hold partial ranges
inside the pages[] map. Hopefully this will be useful for network
receive support as well.

Signed-off-by: Jens Axboe <axboe@suse.de>
diff --git a/include/asm-i386/unistd.h b/include/asm-i386/unistd.h
index d81d6cf..eb4b152 100644
--- a/include/asm-i386/unistd.h
+++ b/include/asm-i386/unistd.h
@@ -321,8 +321,9 @@
 #define __NR_splice		313
 #define __NR_sync_file_range	314
 #define __NR_tee		315
+#define __NR_vmsplice		316
 
-#define NR_syscalls 316
+#define NR_syscalls 317
 
 /*
  * user-visible error numbers are in the range -1 - -128: see