[PATCH] Introduce sys_splice() system call

This adds support for the sys_splice system call. Using a pipe as a
transport, it can connect to files or sockets (latter as output only).

From the splice.c comments:

   "splice": joining two ropes together by interweaving their strands.

   This is the "extended pipe" functionality, where a pipe is used as
   an arbitrary in-memory buffer. Think of a pipe as a small kernel
   buffer that you can use to transfer data from one end to the other.

   The traditional unix read/write is extended with a "splice()" operation
   that transfers data buffers to or from a pipe buffer.

   Named by Larry McVoy, original implementation from Linus, extended by
   Jens to support splicing to files and fixing the initial implementation
   bugs.

Signed-off-by: Jens Axboe <axboe@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

2 files changed, 2 insertions, 0 deletions

diff --git a/arch/i386/kernel/syscall_table.S b/arch/i386/kernel/syscall_table.S
index 326595f3fa4d..ce3ef4fa0551 100644
--- a/arch/i386/kernel/syscall_table.S
+++ b/arch/i386/kernel/syscall_table.S
@@ -312,3 +312,4 @@ ENTRY(sys_call_table)
         .long sys_unshare               /* 310 */
         .long sys_set_robust_list
         .long sys_get_robust_list
+        .long sys_splice
diff --git a/arch/ia64/kernel/entry.S b/arch/ia64/kernel/entry.S
index 0e3eda99e549..750e8e7fbdc3 100644
--- a/arch/ia64/kernel/entry.S
+++ b/arch/ia64/kernel/entry.S
@@ -1605,5 +1605,6 @@ sys_call_table:
         data8 sys_ni_syscall                    // reserved for pselect
         data8 sys_ni_syscall                    // 1295 reserved for ppoll
         data8 sys_unshare
+        data8 sys_splice
 
         .org sys_call_table + 8*NR_syscalls     // guard against failures to increase NR_syscalls