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authorWaldemar Brodkorb <wbx@uclibc-ng.org>2016-07-20 23:41:10 +0200
committerWaldemar Brodkorb <wbx@uclibc-ng.org>2016-10-31 18:00:08 +0100
commit7825930078208462655e107677656c45014e91b4 (patch)
tree0911271efdb803f51d366647d1b0893ec3995d87 /libc/sysdeps/linux/microblaze/clone.S
parenta7f8986f6e81b912b35b46dcad4b8258f75c8b29 (diff)
microblaze: use assembly version of clone, fix vfork
Signed-off-by: Waldemar Brodkorb <wbx@uclibc-ng.org>
Diffstat (limited to 'libc/sysdeps/linux/microblaze/clone.S')
-rw-r--r--libc/sysdeps/linux/microblaze/clone.S78
1 files changed, 78 insertions, 0 deletions
diff --git a/libc/sysdeps/linux/microblaze/clone.S b/libc/sysdeps/linux/microblaze/clone.S
new file mode 100644
index 000000000..46d4fe6b4
--- /dev/null
+++ b/libc/sysdeps/linux/microblaze/clone.S
@@ -0,0 +1,78 @@
+/* Copyright (C) 1996-2016 Free Software Foundation, Inc.
+
+ This file is part of the GNU C Library.
+
+ The GNU C Library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Lesser General Public
+ License as published by the Free Software Foundation; either
+ version 2.1 of the License, or (at your option) any later version.
+
+ The GNU C Library is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public
+ License along with the GNU C Library; if not, see
+ <http://www.gnu.org/licenses/>. */
+
+/* clone() is even more special than fork() as it mucks with stacks
+ and invokes a function in the right context after its all over. */
+
+#include <sysdep.h>
+#define _ERRNO_H 1
+#include <bits/errno.h>
+
+/* int clone (int (*fn)(void *arg), void *child_stack, int flags, void *arg,
+ pid_t *ptid, struct user_desc *tls, pid_t *ctid);
+
+ INCOMING: r5 (fn), r6 (child_stack), r7 (flags), r8 (arg), r9 (ptid)
+ r10 (tls), 28 (r1) ctid
+
+ OUTGOING:
+
+ linux: arch/microblaze/entry.S: sys_clone expects
+ r5 (flags) r6 (child stack) r7 (stack_size) r8 (ptid)r9 (ctid)
+ r10 (tls)
+*/
+
+ .text
+ENTRY (__clone)
+ addik r3,r0,-EINVAL
+ beqi r5,1f ; // Invalid func
+ beqi r6,1f ; // Invalid stack
+ addik r6,r6,-8
+ swi r5,r6,0 ; // Push fn onto child's stack
+ swi r8,r6,4 ; // Push arg for child
+ addk r5,r0,r7 ; // flags for clone() syscall
+ addk r7,r0,r0
+ addk r8,r0,r9 ; // parent tid ptr
+ lwi r9,r1,28 ; // child tid ptr
+ addik r12,r0,SYS_ify(clone)
+ brki r14,8
+ addk r0,r0,r0
+ addik r4,r0,-4095
+ cmpu r4,r4,r3
+ bgei r4,1f
+ beqi r3,L(thread_start)
+ rtsd r15,8
+ nop
+
+L(thread_start):
+ lwi r12,r1,0 ; // fn
+ lwi r5,r1,4 ; // arg
+ brald r15,r12
+ nop
+ addk r5,r0,r3
+ addik r12,r0,SYS_ify(exit)
+ brki r14,8
+ nop
+
+1: rsubk r3,r3,r0
+ rtsd r15,8
+ addik r3,r0,-1 /* delay slot. */
+
+END(__clone)
+
+libc_hidden_def (__clone)
+weak_alias (__clone,clone)