Hi there,
we use Pistachio's system-call bindings in shared libraries, so we
compiled them as position independent code (-fPIC). While there is
already PIC support within the bindings, we still got text-relocations
in our shared libraries. We fixed these issues for our purposes and I
just wanted to share the patch here.
Greetings,
--
Sebastian Sumpf
http://www.genode-labs.com ยท http://genode.org
# HG changeset patch
# Parent b205e69908fea43e434a0ac04232d88ad758f890
diff -r b205e69908fe user/include/l4/ia32/syscalls.h
--- a/user/include/l4/ia32/syscalls.h Mon Sep 13 19:40:40 2010 +0200
+++ b/user/include/l4/ia32/syscalls.h Mon Oct 11 15:10:52 2010 +0200
@@ -47,6 +47,28 @@
# define __L4_CLOBBER_REGS "ebx", "cc"
#endif
+#ifdef __cplusplus
+#define _C_ "C"
+#else
+#define _C_
+#endif
+
+/*
+ * Note: We do not call the __L4*-functions from inline assembly any more,
+ * instead we pass the pointers as input operands. This way there is no need
for
+ * the linker to generate text relocations for position independent code.
+ */
+extern _C_ void __L4_ExchangeRegisters(void);
+extern _C_ void __L4_ThreadControl(void);
+extern _C_ void __L4_SystemClock(void);
+extern _C_ void __L4_ThreadSwitch(void);
+extern _C_ void __L4_Schedule(void);
+extern _C_ void __L4_Ipc(void);
+extern _C_ void __L4_Lipc(void);
+extern _C_ void __L4_Unmap(void);
+extern _C_ void __L4_SpaceControl(void);
+extern _C_ void __L4_ProcessorControl(void);
+extern _C_ void __L4_MemoryControl(void);
L4_INLINE void * L4_KernelInterface (L4_Word_t *ApiVersion,
L4_Word_t *ApiFlags,
@@ -95,32 +117,35 @@
L4_Word_t esi;
} in;
- in.ebp = pager.raw;
- in.ebx = UserDefHandle;
- in.esi = ip;
- in.edi = flags;
+ in.ebp = pager.raw;
+ in.ebx = UserDefHandle;
+ in.esi = ip;
+ in.edi = flags;
__asm__ __volatile__ (
"/* L4_ExchangeRegisters() */ \n"
__L4_SAVE_REGS
" pushl %%esi \n"
+ " pushl %%edi \n"
" movl (%%esi), %%ebp \n"
" movl 4(%%esi), %%edi \n"
" movl 8(%%esi), %%ebx \n"
" movl 12(%%esi), %%esi \n"
- " call __L4_ExchangeRegisters \n"
- " xchgl %%esi, (%%esp) \n"
+ " call *(%%esp) \n"
+ " xchgl %%esi, 4(%%esp) \n"
" movl %%edi, 4(%%esi) \n"
" movl %%ebx, 8(%%esi) \n"
" movl %%ebp, (%%esi) \n"
+ " popl %%edi \n"
" popl %%esi \n"
__L4_RESTORE_REGS
:
"=a" (result), "=c" (*old_control), "=d" (*old_sp), "=S" (*old_ip)
:
- "a" (dest.raw), "c" (control), "d" (sp), "S" (&in)
+ "a" (dest.raw), "c" (control), "d" (sp), "S" (&in),
+ "D" (__L4_ExchangeRegisters)
:
- "edi", "memory", __L4_CLOBBER_REGS);
+ "memory", __L4_CLOBBER_REGS);
old_pager->raw = in.ebp;
*old_flags = in.edi;
@@ -141,7 +166,9 @@
__asm__ __volatile__ (
"/* L4_ThreadControl() */ \n"
__L4_SAVE_REGS
- " call __L4_ThreadControl \n"
+ " movl %%edi, %%ebx \n"
+ " movl %9, %%edi \n"
+ " call *%%ebx \n"
__L4_RESTORE_REGS
: /* outputs */
@@ -156,7 +183,8 @@
"1" (Pager),
"2" (Scheduler),
"3" (SpaceSpecifier),
- "4" (UtcbLocation)
+ "m" (UtcbLocation),
+ "D" (__L4_ThreadControl)
: /* clobbers */
__L4_CLOBBER_REGS);
@@ -171,14 +199,14 @@
__asm__ __volatile__ (
"/* L4_SystemClock() */ \n"
- " call __L4_SystemClock \n"
-
+ " call *%%ecx \n"
: /* outputs */
"=A" (result.raw)
- : /* no inputs */
+ :
+ "c" (__L4_SystemClock)
: /* clobbers */
- "ecx", "esi", "edi");
+ "esi", "edi");
return result;
}
@@ -188,12 +216,13 @@
{
__asm__ __volatile__ (
"/* L4_ThreadSwitch() */ \n"
- " call __L4_ThreadSwitch \n"
+ " call *%%ecx \n"
: /* no outputs */
: /* inputs */
- "a" (dest)
+ "a" (dest),
+ "c" (__L4_ThreadSwitch)
/* no clobbers */
);
@@ -213,7 +242,9 @@
__asm__ __volatile__ (
"/* L4_Schedule() */ \n"
__L4_SAVE_REGS
- " call __L4_Schedule \n"
+ " movl %%edi, %%ebx \n"
+ " movl %9, %%edi \n"
+ " call *%%ebx \n"
__L4_RESTORE_REGS
: /* outputs */
@@ -228,7 +259,8 @@
"1" (PrioControl),
"2" (TimeControl),
"3" (ProcessorControl),
- "4" (PreemptionControl)
+ "m" (PreemptionControl),
+ "D" (__L4_Schedule)
: /* clobbers */
__L4_CLOBBER_REGS);
@@ -246,10 +278,13 @@
L4_Word_t * utcb = __L4_X86_Utcb ();
#if defined(__pic__)
+
__asm__ __volatile__ (
"/* L4_Ipc() */ \n"
__L4_SAVE_REGS
- " call __L4_Ipc \n"
+ " movl %%eax, %%ebx \n"
+ " movl %5, %%eax \n"
+ " call *%%ebx \n"
" movl %%ebp, %%ecx \n"
" movl %%ebx, %%edx \n"
__L4_RESTORE_REGS
@@ -262,11 +297,13 @@
: /* inputs */
"S" (utcb[0]),
- "a" (to.raw),
- "D" (utcb),
+ "m" (to.raw),
+ "D" (utcb),
"c" (Timeouts),
- "d" (FromSpecifier)
+ "d" (FromSpecifier),
+ "a" (__L4_Ipc)
);
+
#else
L4_Word_t dummy;
@@ -282,7 +319,7 @@
"=a" (result),
"=b" (mr1),
"=c" (mr2),
- "=d" (dummy)
+ "=d" (dummy)
: /* inputs */
"S" (utcb[0]),
@@ -317,8 +354,10 @@
__asm__ __volatile__ (
"/* L4_Lipc() */ \n"
__L4_SAVE_REGS
- " call __L4_Lipc \n"
- " movl %%ebp, %%ecx \n"
+ " movl %%eax, %%ebx \n"
+ " movl %5, %%eax \n"
+ " call *%%ebx \n"
+ " movl %%ebp, %%ecx \n"
" movl %%ebx, %%edx \n"
__L4_RESTORE_REGS
@@ -330,10 +369,11 @@
: /* inputs */
"S" (utcb[0]),
- "a" (to.raw),
- "D" (utcb),
+ "m" (to.raw),
+ "D" (utcb),
"c" (Timeouts),
- "d" (FromSpecifier)
+ "d" (FromSpecifier),
+ "a" (__L4_Lipc)
);
#else
L4_Word_t dummy;
@@ -344,7 +384,7 @@
" call __L4_Lipc \n"
" movl %%ebp, %%ecx \n"
__L4_RESTORE_REGS
-
+
: /* outputs */
"=S" (mr0),
"=a" (result),
@@ -355,7 +395,7 @@
: /* inputs */
"S" (utcb[0]),
"a" (to.raw),
- "D" (utcb),
+ "D" (utcb),
"c" (Timeouts),
"d" (FromSpecifier)
);
@@ -378,7 +418,7 @@
__asm__ __volatile__ (
"/* L4_Unmap() */ \n"
__L4_SAVE_REGS
- " call __L4_Unmap \n"
+ " call *%%ecx \n"
__L4_RESTORE_REGS
: /* outputs */
@@ -389,10 +429,11 @@
: /* inputs */
"0" (utcb[0]),
"1" (utcb),
- "2" (control)
+ "2" (control),
+ "c" (__L4_Unmap)
: /* clobbered */
- "ecx", "edx", __L4_CLOBBER_REGS);
+ "edx", __L4_CLOBBER_REGS);
}
@@ -408,7 +449,9 @@
__asm__ __volatile__ (
"/* L4_SpaceControl() */ \n"
__L4_SAVE_REGS
- " call __L4_SpaceControl \n"
+ " movl %%edi, %%ebx \n"
+ " movl %9, %%edi \n"
+ " call *%%ebx \n"
__L4_RESTORE_REGS
: /* outputs */
@@ -423,7 +466,8 @@
"1" (control),
"2" (KernelInterfacePageArea),
"3" (UtcbArea),
- "4" (redirector)
+ "m" (redirector),
+ "D" (__L4_SpaceControl)
: /* clobbers */
__L4_CLOBBER_REGS);
@@ -442,7 +486,7 @@
__asm__ __volatile__ (
"/* L4_ProcessorControl() */ \n"
__L4_SAVE_REGS
- " call __L4_ProcessorControl \n"
+ " call *%%edi \n"
__L4_RESTORE_REGS
: /* outputs */
@@ -456,7 +500,8 @@
"0" (ProcessorNo),
"1" (InternalFrequency),
"2" (ExternalFrequency),
- "3" (voltage)
+ "3" (voltage),
+ "4" (__L4_ProcessorControl)
: /* clobbers */
__L4_CLOBBER_REGS);
@@ -474,11 +519,14 @@
__asm__ __volatile__ (
"/* L4_MemoryControl() */ \n"
__L4_SAVE_REGS
+ " pushl %%edi \n"
+ " movl %8, %%edi \n"
" movl 12(%6), %%ebp \n"
" movl 8(%6), %%ebx \n"
" movl 4(%6), %%edx \n"
" movl (%6), %%ecx \n"
- " call __L4_MemoryControl \n"
+ " call *(%%esp) \n"
+ " popl %%edi \n"
__L4_RESTORE_REGS
: /* outputs */
@@ -492,7 +540,8 @@
"0" (control),
"1" (attributes),
"3" (utcb[0]),
- "4" (utcb)
+ "m" (utcb),
+ "4" (__L4_MemoryControl)
: /* clobbers */
__L4_CLOBBER_REGS);
