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-rw-r--r--arch/um/kernel/skas/clone.c44
1 files changed, 44 insertions, 0 deletions
diff --git a/arch/um/kernel/skas/clone.c b/arch/um/kernel/skas/clone.c
new file mode 100644
index 000000000000..4dc55f10cd18
--- /dev/null
+++ b/arch/um/kernel/skas/clone.c
@@ -0,0 +1,44 @@
+#include <sched.h>
+#include <signal.h>
+#include <sys/mman.h>
+#include <sys/time.h>
+#include <asm/unistd.h>
+#include <asm/page.h>
+#include "ptrace_user.h"
+#include "skas.h"
+#include "stub-data.h"
+#include "uml-config.h"
+#include "sysdep/stub.h"
+
+/* This is in a separate file because it needs to be compiled with any
+ * extraneous gcc flags (-pg, -fprofile-arcs, -ftest-coverage) disabled
+ */
+void __attribute__ ((__section__ (".__syscall_stub")))
+stub_clone_handler(void)
+{
+ long err;
+ struct stub_data *from = (struct stub_data *) UML_CONFIG_STUB_DATA;
+
+ err = stub_syscall2(__NR_clone, CLONE_PARENT | CLONE_FILES | SIGCHLD,
+ UML_CONFIG_STUB_DATA + PAGE_SIZE / 2 -
+ sizeof(void *));
+ if(err != 0)
+ goto out;
+
+ err = stub_syscall4(__NR_ptrace, PTRACE_TRACEME, 0, 0, 0);
+ if(err)
+ goto out;
+
+ err = stub_syscall3(__NR_setitimer, ITIMER_VIRTUAL,
+ (long) &from->timer, 0);
+ if(err)
+ goto out;
+
+ err = stub_syscall6(STUB_MMAP_NR, UML_CONFIG_STUB_DATA, PAGE_SIZE,
+ PROT_READ | PROT_WRITE, MAP_FIXED | MAP_SHARED,
+ from->fd, from->offset);
+ out:
+ /* save current result. Parent: pid; child: retcode of mmap */
+ from->err = err;
+ trap_myself();
+}