avr32: wire up preadv2 and pwritev2 syscalls

This patch wires up the new preadv2 and pwritev2 syscall on AVR32.

On AVR32, all parameters beyond the 5th are passed on the stack. System
calls don't use the stack -- they borrow a callee-saved register
instead. This means that syscalls that take 6 parameters must be called
through a stub that pushes the last parameter on the stack.

Signed-off-by: Hans-Christian Noren Egtvedt <egtvedt@samfundet.no>

3 files changed, 22 insertions, 0 deletions

diff --git a/arch/avr32/include/uapi/asm/unistd.h b/arch/avr32/include/uapi/asm/unistd.h
index 60c0f3afc1f9..d0c1f6db4b8f 100644
--- a/arch/avr32/include/uapi/asm/unistd.h
+++ b/arch/avr32/include/uapi/asm/unistd.h
@@ -338,5 +338,7 @@
 #define __NR_membarrier         323
 #define __NR_mlock2             324
 #define __NR_copy_file_range    325
+#define __NR_preadv2            326
+#define __NR_pwritev2           327
 
 #endif /* _UAPI__ASM_AVR32_UNISTD_H */
diff --git a/arch/avr32/kernel/syscall-stubs.S b/arch/avr32/kernel/syscall-stubs.S
index cb3991552f14..cb256534ed92 100644
--- a/arch/avr32/kernel/syscall-stubs.S
+++ b/arch/avr32/kernel/syscall-stubs.S
@@ -133,3 +133,21 @@ __sys_copy_file_range:
         call    sys_copy_file_range
         sub     sp, -4
         popm    pc
+
+        .global __sys_preadv2
+        .type   __sys_preadv2,@function
+__sys_preadv2:
+        pushm   lr
+        st.w    --sp, ARG6
+        call    sys_preadv2
+        sub     sp, -4
+        popm    pc
+
+        .global __sys_pwritev2
+        .type   __sys_pwritev2,@function
+__sys_pwritev2:
+        pushm   lr
+        st.w    --sp, ARG6
+        call    sys_pwritev2
+        sub     sp, -4
+        popm    pc
diff --git a/arch/avr32/kernel/syscall_table.S b/arch/avr32/kernel/syscall_table.S
index 64d71a781fa8..0eaf94b7a67c 100644
--- a/arch/avr32/kernel/syscall_table.S
+++ b/arch/avr32/kernel/syscall_table.S
@@ -339,4 +339,6 @@ sys_call_table:
         .long   sys_membarrier
         .long   sys_mlock2
         .long   __sys_copy_file_range   /* 325 */
+        .long   __sys_preadv2
+        .long   __sys_pwritev2
         .long   sys_ni_syscall          /* r8 is saturated at nr_syscalls */