[parisc-linux] Re: [parisc-linux-cvs] linux-2.6 carlos
Carlos O'Donell
carlos at baldric.uwo.ca
Fri Apr 30 09:57:45 MDT 2004
On Fri, Apr 30, 2004 at 08:15:48AM -0600, Carlos O'Donell wrote:
> CVSROOT: /var/cvs
> Module name: linux-2.6
> Changes by: carlos 04/04/30 08:15:48
>
> Modified files:
> include/asm-parisc: unistd.h
>
> Log message:
> Update K_INLINE_SYSCALL so userspace apps using the macro work properly.
Lifted from the version I wrote for glibc. I get to clean this up yet
again when we remove the register saves across syscalls.
Index: include/asm-parisc/unistd.h
===================================================================
RCS file: /var/cvs/linux-2.6/include/asm-parisc/unistd.h,v
retrieving revision 1.5
diff -u -p -r1.5 unistd.h
--- a/include/asm-parisc/unistd.h 28 Apr 2004 23:13:37 -0000 1.5
+++ b/include/asm-parisc/unistd.h 30 Apr 2004 14:15:17 -0000
@@ -735,94 +735,141 @@
#ifndef __ASSEMBLY__
-/* The old syscall code here didn't work, and it looks like it's only used
- * by applications such as fdisk which for some reason need to produce
- * their own syscall instead of using same from libc. The code below
- * is leveraged from glibc/sysdeps/unix/sysv/linux/hppa/sysdep.h where
- * it is essentially duplicated -- which sucks. -PB
- */
-
#define SYS_ify(syscall_name) __NR_##syscall_name
-/* The system call number MUST ALWAYS be loaded in the delay slot of
- the ble instruction, or restarting system calls WILL NOT WORK. See
- arch/parisc/kernel/signal.c - dhd, 2000-07-26 */
-#define K_INLINE_SYSCALL(name, nr, args...) ({ \
- unsigned long __sys_res; \
- { \
- register unsigned long __res asm("r28"); \
- K_LOAD_ARGS_##nr(args) \
- asm volatile( \
- "ble 0x100(%%sr2, %%r0)\n\t" \
- " ldi %1, %%r20" \
- : "=r" (__res) \
- : "i" (SYS_ify(name)) K_ASM_ARGS_##nr \
- ); \
- __sys_res = __res; \
- } \
- if (__sys_res >= (unsigned long)-4095) { \
- errno = -__sys_res; \
- __sys_res = (unsigned long)-1; \
- } \
- __sys_res; \
+/* Assume all syscalls are done from PIC code just to be
+ * safe. The worst case scenario is that you lose a register
+ * and save/restore r19 across the syscall. */
+#define PIC
+
+#ifndef ASM_LINE_SEP
+# define ASM_LINE_SEP ;
+#endif
+
+/* Definition taken from glibc 2.3.3
+ * sysdeps/unix/sysv/linux/hppa/sysdep.h
+ */
+
+#ifdef PIC
+/* WARNING: CANNOT BE USED IN A NOP! */
+# define K_STW_PIC stw %r19, -32(%sr0, %sp) ASM_LINE_SEP
+# define K_LDW_PIC ldw -32(%sr0, %sp), %r19 ASM_LINE_SEP
+# define K_STW_ASM_PIC " copy %%r19, %%r4\n"
+# define K_LDW_ASM_PIC " copy %%r4, %%r19\n"
+# define K_USING_GR4 "%r4",
+#else
+# define K_STW_PIC ASM_LINE_SEP
+# define K_LDW_PIC ASM_LINE_SEP
+# define K_STW_ASM_PIC " \n"
+# define K_LDW_ASM_PIC " \n"
+# define K_USING_GR4
+#endif
+
+/* GCC has to be warned that a syscall may clobber all the ABI
+ registers listed as "caller-saves", see page 8, Table 2
+ in section 2.2.6 of the PA-RISC RUN-TIME architecture
+ document. However! r28 is the result and will conflict with
+ the clobber list so it is left out. Also the input arguments
+ registers r20 -> r26 will conflict with the list so they
+ are treated specially. Although r19 is clobbered by the syscall
+ we cannot say this because it would violate ABI, thus we say
+ r4 is clobbered and use that register to save/restore r19
+ across the syscall. */
+
+#define K_CALL_CLOB_REGS "%r1", "%r2", K_USING_GR4 \
+ "%r20", "%r29", "%r31"
+
+#undef K_INLINE_SYSCALL
+#define K_INLINE_SYSCALL(name, nr, args...) ({ \
+ long __sys_res; \
+ { \
+ register unsigned long __res asm("r28"); \
+ K_LOAD_ARGS_##nr(args) \
+ /* FIXME: HACK stw/ldw r19 around syscall */ \
+ asm volatile( \
+ K_STW_ASM_PIC \
+ " ble 0x100(%%sr2, %%r0)\n" \
+ " ldi %1, %%r20\n" \
+ K_LDW_ASM_PIC \
+ : "=r" (__res) \
+ : "i" (SYS_ify(name)) K_ASM_ARGS_##nr \
+ : K_CALL_CLOB_REGS K_CLOB_ARGS_##nr \
+ ); \
+ __sys_res = (long)__res; \
+ } \
+ if ( (unsigned long)__sys_res >= (unsigned long)-4095 ){ \
+ errno = -__sys_res); \
+ __sys_res = -1; \
+ } \
+ __sys_res; \
})
#define K_LOAD_ARGS_0()
-#define K_LOAD_ARGS_1(r26) \
- register unsigned long __r26 __asm__("r26") = (unsigned long)r26; \
- K_LOAD_ARGS_0()
-#define K_LOAD_ARGS_2(r26,r25) \
- register unsigned long __r25 __asm__("r25") = (unsigned long)r25; \
- K_LOAD_ARGS_1(r26)
-#define K_LOAD_ARGS_3(r26,r25,r24) \
- register unsigned long __r24 __asm__("r24") = (unsigned long)r24; \
- K_LOAD_ARGS_2(r26,r25)
-#define K_LOAD_ARGS_4(r26,r25,r24,r23) \
- register unsigned long __r23 __asm__("r23") = (unsigned long)r23; \
- K_LOAD_ARGS_3(r26,r25,r24)
-#define K_LOAD_ARGS_5(r26,r25,r24,r23,r22) \
- register unsigned long __r22 __asm__("r22") = (unsigned long)r22; \
- K_LOAD_ARGS_4(r26,r25,r24,r23)
-#define K_LOAD_ARGS_6(r26,r25,r24,r23,r22,r21) \
- register unsigned long __r21 __asm__("r21") = (unsigned long)r21; \
- K_LOAD_ARGS_5(r26,r25,r24,r23,r22)
+#define K_LOAD_ARGS_1(r26) \
+ register unsigned long __r26 __asm__("r26") = (unsigned long)(r26); \
+ K_LOAD_ARGS_0()
+#define K_LOAD_ARGS_2(r26,r25) \
+ register unsigned long __r25 __asm__("r25") = (unsigned long)(r25); \
+ K_LOAD_ARGS_1(r26)
+#define K_LOAD_ARGS_3(r26,r25,r24) \
+ register unsigned long __r24 __asm__("r24") = (unsigned long)(r24); \
+ K_LOAD_ARGS_2(r26,r25)
+#define K_LOAD_ARGS_4(r26,r25,r24,r23) \
+ register unsigned long __r23 __asm__("r23") = (unsigned long)(r23); \
+ K_LOAD_ARGS_3(r26,r25,r24)
+#define K_LOAD_ARGS_5(r26,r25,r24,r23,r22) \
+ register unsigned long __r22 __asm__("r22") = (unsigned long)(r22); \
+ K_LOAD_ARGS_4(r26,r25,r24,r23)
+#define K_LOAD_ARGS_6(r26,r25,r24,r23,r22,r21) \
+ register unsigned long __r21 __asm__("r21") = (unsigned long)(r21); \
+ K_LOAD_ARGS_5(r26,r25,r24,r23,r22)
+/* Even with zero args we use r20 for the syscall number */
#define K_ASM_ARGS_0
-#define K_ASM_ARGS_1 , "r" (__r26)
-#define K_ASM_ARGS_2 , "r" (__r26), "r" (__r25)
-#define K_ASM_ARGS_3 , "r" (__r26), "r" (__r25), "r" (__r24)
-#define K_ASM_ARGS_4 , "r" (__r26), "r" (__r25), "r" (__r24), "r" (__r23)
-#define K_ASM_ARGS_5 , "r" (__r26), "r" (__r25), "r" (__r24), "r" (__r23), "r" (__r22)
-#define K_ASM_ARGS_6 , "r" (__r26), "r" (__r25), "r" (__r24), "r" (__r23), "r" (__r22), "r" (__r21)
+#define K_ASM_ARGS_1 K_ASM_ARGS_0, "r" (__r26)
+#define K_ASM_ARGS_2 K_ASM_ARGS_1, "r" (__r25)
+#define K_ASM_ARGS_3 K_ASM_ARGS_2, "r" (__r24)
+#define K_ASM_ARGS_4 K_ASM_ARGS_3, "r" (__r23)
+#define K_ASM_ARGS_5 K_ASM_ARGS_4, "r" (__r22)
+#define K_ASM_ARGS_6 K_ASM_ARGS_5, "r" (__r21)
+
+/* The registers not listed as inputs but clobbered */
+#define K_CLOB_ARGS_6
+#define K_CLOB_ARGS_5 K_CLOB_ARGS_6, "%r21"
+#define K_CLOB_ARGS_4 K_CLOB_ARGS_5, "%r22"
+#define K_CLOB_ARGS_3 K_CLOB_ARGS_4, "%r23"
+#define K_CLOB_ARGS_2 K_CLOB_ARGS_3, "%r24"
+#define K_CLOB_ARGS_1 K_CLOB_ARGS_2, "%r25"
+#define K_CLOB_ARGS_0 K_CLOB_ARGS_1, "%r26"
-#define _syscall0(type,name) \
-type name(void) \
-{ \
- return K_INLINE_SYSCALL(name, 0); \
+#define _syscall0(type,name) \
+type name(void) \
+{ \
+ return K_INLINE_SYSCALL(name, 0); \
}
-#define _syscall1(type,name,type1,arg1) \
-type name(type1 arg1) \
-{ \
- return K_INLINE_SYSCALL(name, 1, arg1); \
+#define _syscall1(type,name,type1,arg1) \
+type name(type1 arg1) \
+{ \
+ return K_INLINE_SYSCALL(name, 1, arg1); \
}
-#define _syscall2(type,name,type1,arg1,type2,arg2) \
-type name(type1 arg1, type2 arg2) \
-{ \
- return K_INLINE_SYSCALL(name, 2, arg1, arg2); \
+#define _syscall2(type,name,type1,arg1,type2,arg2) \
+type name(type1 arg1, type2 arg2) \
+{ \
+ return K_INLINE_SYSCALL(name, 2, arg1, arg2); \
}
-#define _syscall3(type,name,type1,arg1,type2,arg2,type3,arg3) \
-type name(type1 arg1, type2 arg2, type3 arg3) \
-{ \
- return K_INLINE_SYSCALL(name, 3, arg1, arg2, arg3); \
+#define _syscall3(type,name,type1,arg1,type2,arg2,type3,arg3) \
+type name(type1 arg1, type2 arg2, type3 arg3) \
+{ \
+ return K_INLINE_SYSCALL(name, 3, arg1, arg2, arg3); \
}
-#define _syscall4(type,name,type1,arg1,type2,arg2,type3,arg3,type4,arg4) \
-type name(type1 arg1, type2 arg2, type3 arg3, type4 arg4) \
-{ \
- return K_INLINE_SYSCALL(name, 4, arg1, arg2, arg3, arg4); \
+#define _syscall4(type,name,type1,arg1,type2,arg2,type3,arg3,type4,arg4) \
+type name(type1 arg1, type2 arg2, type3 arg3, type4 arg4) \
+{ \
+ return K_INLINE_SYSCALL(name, 4, arg1, arg2, arg3, arg4); \
}
/* select takes 5 arguments */
@@ -834,13 +881,11 @@ type name(type1 arg1, type2 arg2, type3
/* mmap & mmap2 take 6 arguments */
-
#define _syscall6(type,name,type1,arg1,type2,arg2,type3,arg3,type4,arg4,type5,arg5,type6,arg6) \
type name(type1 arg1, type2 arg2, type3 arg3, type4 arg4, type5 arg5, type6 arg6) \
-{ \
+{ \
return K_INLINE_SYSCALL(name, 6, arg1, arg2, arg3, arg4, arg5, arg6); \
}
-
#ifdef __KERNEL_SYSCALLS__
More information about the parisc-linux
mailing list