[PATCH] uml: start cross-build support : mk_user_constants

Beginning of cross-build fixes.  Instead of expecting that mk_user_constants
(compiled and executed on the build box) will see the sizeof, etc.  for target
box, we do what every architecture already does for asm-offsets.  Namely, have
user-offsets.c compiled *for* *target* into user-offsets.s and sed it into the
header with relevant constants.  We don't need to reinvent any wheels - all
tools are already there.

This patch deals with mk_user_constants.  It doesn't assume any relationship
between target and build environment anymore - we pick all defines we need
from user-offsets.h.  Later patches will deal with the rest of mk_...  helpers
in the same way.

Signed-off-by: Al Viro <viro@parcelfarce.linux.theplanet.co.uk>
Signed-off-by: Jeff Dike <jdike@addtoit.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

1 files changed, 69 insertions, 0 deletions

diff --git a/arch/um/sys-i386/user-offsets.c b/arch/um/sys-i386/user-offsets.c
new file mode 100644
index 0000000..3ceaabc
--- /dev/null
+++ b/arch/um/sys-i386/user-offsets.c
@@ -0,0 +1,69 @@
+#include <stdio.h>
+#include <signal.h>
+#include <asm/ptrace.h>
+#include <asm/user.h>
+#include <linux/stddef.h>
+
+#define DEFINE(sym, val) \
+        asm volatile("\n->" #sym " %0 " #val : : "i" (val))
+
+#define OFFSET(sym, str, mem) \
+	DEFINE(sym, offsetof(struct str, mem));
+
+void foo(void)
+{
+	OFFSET(SC_IP, sigcontext, eip);
+	OFFSET(SC_SP, sigcontext, esp);
+	OFFSET(SC_FS, sigcontext, fs);
+	OFFSET(SC_GS, sigcontext, gs);
+	OFFSET(SC_DS, sigcontext, ds);
+	OFFSET(SC_ES, sigcontext, es);
+	OFFSET(SC_SS, sigcontext, ss);
+	OFFSET(SC_CS, sigcontext, cs);
+	OFFSET(SC_EFLAGS, sigcontext, eflags);
+	OFFSET(SC_EAX, sigcontext, eax);
+	OFFSET(SC_EBX, sigcontext, ebx);
+	OFFSET(SC_ECX, sigcontext, ecx);
+	OFFSET(SC_EDX, sigcontext, edx);
+	OFFSET(SC_EDI, sigcontext, edi);
+	OFFSET(SC_ESI, sigcontext, esi);
+	OFFSET(SC_EBP, sigcontext, ebp);
+	OFFSET(SC_TRAPNO, sigcontext, trapno);
+	OFFSET(SC_ERR, sigcontext, err);
+	OFFSET(SC_CR2, sigcontext, cr2);
+	OFFSET(SC_FPSTATE, sigcontext, fpstate);
+	OFFSET(SC_SIGMASK, sigcontext, oldmask);
+	OFFSET(SC_FP_CW, _fpstate, cw);
+	OFFSET(SC_FP_SW, _fpstate, sw);
+	OFFSET(SC_FP_TAG, _fpstate, tag);
+	OFFSET(SC_FP_IPOFF, _fpstate, ipoff);
+	OFFSET(SC_FP_CSSEL, _fpstate, cssel);
+	OFFSET(SC_FP_DATAOFF, _fpstate, dataoff);
+	OFFSET(SC_FP_DATASEL, _fpstate, datasel);
+	OFFSET(SC_FP_ST, _fpstate, _st);
+	OFFSET(SC_FXSR_ENV, _fpstate, _fxsr_env);
+
+	DEFINE(HOST_FRAME_SIZE, FRAME_SIZE);
+	DEFINE(HOST_FP_SIZE,
+		sizeof(struct user_i387_struct) / sizeof(unsigned long));
+	DEFINE(HOST_XFP_SIZE,
+	       sizeof(struct user_fxsr_struct) / sizeof(unsigned long));
+
+	DEFINE(HOST_IP, EIP);
+	DEFINE(HOST_SP, UESP);
+	DEFINE(HOST_EFLAGS, EFL);
+	DEFINE(HOST_EAX, EAX);
+	DEFINE(HOST_EBX, EBX);
+	DEFINE(HOST_ECX, ECX);
+	DEFINE(HOST_EDX, EDX);
+	DEFINE(HOST_ESI, ESI);
+	DEFINE(HOST_EDI, EDI);
+	DEFINE(HOST_EBP, EBP);
+	DEFINE(HOST_CS, CS);
+	DEFINE(HOST_SS, SS);
+	DEFINE(HOST_DS, DS);
+	DEFINE(HOST_FS, FS);
+	DEFINE(HOST_ES, ES);
+	DEFINE(HOST_GS, GS);
+	DEFINE(__UM_FRAME_SIZE, sizeof(struct user_regs_struct));
+}