S/390: Make ucontext_t extendible.

5 files changed, 140 insertions, 7 deletions

diff --git a/sysdeps/unix/sysv/linux/s390/s390-64/getcontext.S b/sysdeps/unix/sysv/linux/s390/s390-64/getcontext-common.S
index db271c5dc5..3e61e30702 100644
--- a/sysdeps/unix/sysv/linux/s390/s390-64/getcontext.S
+++ b/sysdeps/unix/sysv/linux/s390/s390-64/getcontext-common.S
@@ -33,7 +33,7 @@
 ENTRY(__getcontext)
 	lgr     %r1,%r2
 
-	/* sigprocmask (SIG_BLOCK, NULL, &sc->sc_mask).  */
+	/* rt_sigprocmask (SIG_BLOCK, NULL, &sc->sc_mask, sigsetsize).  */
 	la      %r2,SIG_BLOCK
 	slgr	%r3,%r3
 	la	%r4,SC_MASK(%r1)
@@ -62,6 +62,10 @@ ENTRY(__getcontext)
 	/* Set __getcontext return value to 0.  */
 	slgr    %r2,%r2
 
+	/* Store the version number into the uc_flags field.  So far
+	   we do not make use of the reserved bytes so we store a zero.  */
+	stg	%r2,SC_FLGS(%r1)
+
 	/* Store access registers.  */
 	stam    %a0,%a15,SC_ACRS(%r1)
 
diff --git a/sysdeps/unix/sysv/linux/s390/s390-64/nptl/libc.abilist b/sysdeps/unix/sysv/linux/s390/s390-64/nptl/libc.abilist
index 05b5286058..4576fc8d14 100644
--- a/sysdeps/unix/sysv/linux/s390/s390-64/nptl/libc.abilist
+++ b/sysdeps/unix/sysv/linux/s390/s390-64/nptl/libc.abilist
@@ -102,6 +102,7 @@ GLIBC_2.19
  __sigsetjmp F
  _longjmp F
  _setjmp F
+ getcontext F
  longjmp F
  setjmp F
  siglongjmp F
diff --git a/sysdeps/unix/sysv/linux/s390/s390-64/swapcontext.S b/sysdeps/unix/sysv/linux/s390/s390-64/swapcontext.S
index ec92898964..ac74b6bc08 100644
--- a/sysdeps/unix/sysv/linux/s390/s390-64/swapcontext.S
+++ b/sysdeps/unix/sysv/linux/s390/s390-64/swapcontext.S
@@ -33,6 +33,9 @@
   other than the PRESERVED state.  */
 
 ENTRY(__swapcontext)
+	/* While not part of the ABI a system call never clobbers r0
+	   or r1.  So keeping the values here while calling
+	   rt_sigprocmask is ok.  */
 	lgr	%r1,%r2
 	lgr     %r0,%r3
 
@@ -62,21 +65,25 @@ ENTRY(__swapcontext)
 	std     %f14,SC_FPRS+112(%r1)
 	std     %f15,SC_FPRS+120(%r1)
 
-	/* Set __swapcontext return value to 0.  */
-	slgr     %r2,%r2
-
 	/* Store access registers.  */
 	stam    %a0,%a15,SC_ACRS(%r1)
 
+	/* Set __swapcontext return value to 0.  */
+	slgr	%r2,%r2
+
 	/* Store general purpose registers.  */
 	stmg    %r0,%r15,SC_GPRS(%r1)
 
-	/* sigprocmask (SIG_SETMASK, &sc->sc_mask, NULL).  */
-	la      %r2,SIG_BLOCK
+	/* Copy uc_flags into the new ucontext_t.  */
 	lgr	%r5,%r0
+	lg	%r2,SC_FLGS(%r5)
+	stg	%r2,SC_FLGS(%r1)
+
+	/* rt_sigprocmask (SIG_SETMASK, &sc->sc_mask, NULL, sigsetsize).  */
+	la      %r2,SIG_BLOCK
 	la	%r3,SC_MASK(%r5)
-	lghi	%r5,_NSIG8
 	slgr	%r4,%r4
+	lghi	%r5,_NSIG8
 	svc	SYS_ify(rt_sigprocmask)
 
 	/* Load fpu context.  */
diff --git a/sysdeps/unix/sysv/linux/s390/s390-64/sys/ucontext.h b/sysdeps/unix/sysv/linux/s390/s390-64/sys/ucontext.h
new file mode 100644
index 0000000000..b563e98f05
--- /dev/null
+++ b/sysdeps/unix/sysv/linux/s390/s390-64/sys/ucontext.h
@@ -0,0 +1,96 @@
+/* Copyright (C) 2000-2014 Free Software Foundation, Inc.
+   Contributed by Denis Joseph Barrow (djbarrow@de.ibm.com).
+   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/>.  */
+
+#ifndef _SYS_UCONTEXT_H
+#define _SYS_UCONTEXT_H	1
+/* Forward definition to avoid parse errors */
+struct ucontext;
+typedef struct ucontext ucontext_t;
+#include <features.h>
+#include <signal.h>
+
+/* We need the signal context definitions even if they are not used
+   included in <signal.h>.  */
+#include <bits/sigcontext.h>
+
+/* Type for a program status word.  */
+typedef struct
+{
+  unsigned long mask;
+  unsigned long addr;
+} __attribute__ ((__aligned__(8))) __psw_t;
+
+/* Type for a general-purpose register.  */
+typedef unsigned long greg_t;
+
+/* And the whole bunch of them.  We should have used `struct s390_regs',
+   but to avoid name space pollution and since the tradition says that
+   the register set is an array, we make gregset_t a simple array
+   that has the same size as s390_regs.  This is needed for the
+   elf_prstatus structure.  */
+#if __WORDSIZE == 64
+# define NGREG 27
+#else
+# define NGREG 36
+#endif
+/* Must match kernels psw_t alignment.  */
+typedef greg_t gregset_t[NGREG] __attribute__ ((__aligned__(8)));
+
+typedef union
+  {
+    double  d;
+    float   f;
+  } fpreg_t;
+
+/* Register set for the floating-point registers.  */
+typedef struct
+  {
+    unsigned int fpc;
+    fpreg_t fprs[16];
+  } fpregset_t;
+
+/* Bit 0 is reserved for the uc_high_gprs field only available in the
+   32 bit version of ucontext_t.  This bit will never be set for 64
+   bit.  */
+#define UCONTEXT_UC_FLAGS_HIGH_GPRS (1UL << 0)
+
+/* A new uc_flags constant will be defined when actually making use of
+   the reserved space: UCONTEXT_UCFLAGS_RESERVED (1UL << 1).  */
+
+/* Context to describe whole processor state.  */
+typedef struct
+  {
+    __psw_t psw;
+    unsigned long gregs[16];
+    unsigned int aregs[16];
+    fpregset_t fpregs;
+  } mcontext_t;
+
+/* Userlevel context.  */
+struct ucontext
+  {
+    unsigned long int uc_flags;
+    struct ucontext *uc_link;
+    stack_t uc_stack;
+    mcontext_t uc_mcontext;
+    __sigset_t uc_sigmask;
+    char reserved[512];
+  };
+
+
+#endif /* sys/ucontext.h */
diff --git a/sysdeps/unix/sysv/linux/s390/s390-64/ucontext_i.sym b/sysdeps/unix/sysv/linux/s390/s390-64/ucontext_i.sym
new file mode 100644
index 0000000000..6cc9f19624
--- /dev/null
+++ b/sysdeps/unix/sysv/linux/s390/s390-64/ucontext_i.sym
@@ -0,0 +1,25 @@
+#include <stddef.h>
+#include <signal.h>
+#include <sys/ucontext.h>
+
+--
+
+SIG_BLOCK
+SIG_UNBLOCK
+SIG_SETMASK
+
+_NSIG8          (_NSIG / 8)
+
+#define ucontext(member)	offsetof (ucontext_t, member)
+#define mcontext(member)	ucontext (uc_mcontext.member)
+
+SC_FLGS		ucontext (uc_flags)
+SC_LINK		ucontext (uc_link)
+SC_STCK		ucontext (uc_stack.ss_sp)
+SC_STSZ		ucontext (uc_stack.ss_size)
+SC_PSW		mcontext (psw)
+SC_GPRS		mcontext (gregs)
+SC_ACRS		mcontext (aregs)
+SC_FPC		mcontext (fpregs.fpc)
+SC_FPRS		mcontext (fpregs.fprs)
+SC_MASK		ucontext (uc_sigmask)