[S390] Inline assembly cleanup.

Major cleanup of all s390 inline assemblies. They now have a common
coding style. Quite a few have been shortened, mainly by using register
asm variables. Use of the EX_TABLE macro helps  as well. The atomic ops,
bit ops and locking inlines new use the Q-constraint if a newer gcc
is used.  That results in slightly better code.

Thanks to Christian Borntraeger for proof reading the changes.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

1 files changed, 55 insertions, 121 deletions

diff --git a/include/asm-s390/checksum.h b/include/asm-s390/checksum.h
index 471f2af2b16a..37c362d89fad 100644
--- a/include/asm-s390/checksum.h
+++ b/include/asm-s390/checksum.h
@@ -30,57 +30,13 @@
 static inline unsigned int
 csum_partial(const unsigned char * buff, int len, unsigned int sum)
 {
-        /*
-         * Experiments with ethernet and slip connections show that buf
-         * is aligned on either a 2-byte or 4-byte boundary.
-         */
-#ifndef __s390x__
-        register_pair rp;
-
-        rp.subreg.even = (unsigned long) buff;
-        rp.subreg.odd = (unsigned long) len;
-        __asm__ __volatile__ (
-                "0:  cksm %0,%1\n"      /* do checksum on longs */
-                "    jo   0b\n"
-                : "+&d" (sum), "+&a" (rp) : : "cc", "memory" );
-#else /* __s390x__ */
-        __asm__ __volatile__ (
-                "    lgr  2,%1\n"    /* address in gpr 2 */
-                "    lgfr 3,%2\n"    /* length in gpr 3 */
-                "0:  cksm %0,2\n"    /* do checksum on longs */
-                "    jo   0b\n"
-                : "+&d" (sum)
-                : "d" (buff), "d" (len)
-                : "cc", "memory", "2", "3" );
-#endif /* __s390x__ */
-        return sum;
-}
-
-/*
- * csum_partial as an inline function
- */
-static inline unsigned int 
-csum_partial_inline(const unsigned char * buff, int len, unsigned int sum)
-{
-#ifndef __s390x__
-        register_pair rp;
+        register unsigned long reg2 asm("2") = (unsigned long) buff;
+        register unsigned long reg3 asm("3") = (unsigned long) len;
 
-        rp.subreg.even = (unsigned long) buff;
-        rp.subreg.odd = (unsigned long) len;
-        __asm__ __volatile__ (
-                "0:  cksm %0,%1\n"    /* do checksum on longs */
-                "    jo   0b\n"
-                : "+&d" (sum), "+&a" (rp) : : "cc", "memory" );
-#else /* __s390x__ */
-        __asm__ __volatile__ (
-                "    lgr  2,%1\n"    /* address in gpr 2 */
-                "    lgfr 3,%2\n"    /* length in gpr 3 */
-                "0:  cksm %0,2\n"    /* do checksum on longs */
-                "    jo   0b\n"
-                : "+&d" (sum)
-                : "d" (buff), "d" (len)
-                : "cc", "memory", "2", "3" );
-#endif /* __s390x__ */
+        asm volatile(
+                "0:     cksm    %0,%1\n"        /* do checksum on longs */
+                "       jo      0b\n"
+                : "+d" (sum), "+d" (reg2), "+d" (reg3) : : "cc", "memory");
         return sum;
 }
 
@@ -114,7 +70,7 @@ static inline unsigned int
 csum_partial_copy_nocheck (const char *src, char *dst, int len, unsigned int sum)
 {
         memcpy(dst,src,len);
-        return csum_partial_inline(dst, len, sum);
+        return csum_partial(dst, len, sum);
 }
 
 /*
@@ -126,22 +82,22 @@ csum_fold(unsigned int sum)
 #ifndef __s390x__
         register_pair rp;
 
-        __asm__ __volatile__ (
-                "    slr  %N1,%N1\n" /* %0 = H L */
-                "    lr   %1,%0\n"   /* %0 = H L, %1 = H L 0 0 */
-                "    srdl %1,16\n"   /* %0 = H L, %1 = 0 H L 0 */
-                "    alr  %1,%N1\n"  /* %0 = H L, %1 = L H L 0 */
-                "    alr  %0,%1\n"   /* %0 = H+L+C L+H */
-                "    srl  %0,16\n"   /* %0 = H+L+C */
-                : "+&d" (sum), "=d" (rp) : : "cc" );
+        asm volatile(
+                "       slr     %N1,%N1\n"      /* %0 = H L */
+                "       lr      %1,%0\n"        /* %0 = H L, %1 = H L 0 0 */
+                "       srdl    %1,16\n"        /* %0 = H L, %1 = 0 H L 0 */
+                "       alr     %1,%N1\n"       /* %0 = H L, %1 = L H L 0 */
+                "       alr     %0,%1\n"        /* %0 = H+L+C L+H */
+                "       srl     %0,16\n"        /* %0 = H+L+C */
+                : "+&d" (sum), "=d" (rp) : : "cc");
 #else /* __s390x__ */
-        __asm__ __volatile__ (
-                "    sr   3,3\n"   /* %0 = H*65536 + L */
-                "    lr   2,%0\n"  /* %0 = H L, R2/R3 = H L / 0 0 */
-                "    srdl 2,16\n"  /* %0 = H L, R2/R3 = 0 H / L 0 */
-                "    alr  2,3\n"   /* %0 = H L, R2/R3 = L H / L 0 */
-                "    alr  %0,2\n"  /* %0 = H+L+C L+H */
-                "    srl  %0,16\n" /* %0 = H+L+C */
+        asm volatile(
+                "       sr      3,3\n"          /* %0 = H*65536 + L */
+                "       lr      2,%0\n"         /* %0 = H L, 2/3 = H L / 0 0 */
+                "       srdl    2,16\n"         /* %0 = H L, 2/3 = 0 H / L 0 */
+                "       alr     2,3\n"          /* %0 = H L, 2/3 = L H / L 0 */
+                "       alr     %0,2\n"         /* %0 = H+L+C L+H */
+                "       srl     %0,16\n"        /* %0 = H+L+C */
                 : "+&d" (sum) : : "cc", "2", "3");
 #endif /* __s390x__ */
         return ((unsigned short) ~sum);
@@ -155,29 +111,7 @@ csum_fold(unsigned int sum)
 static inline unsigned short
 ip_fast_csum(unsigned char *iph, unsigned int ihl)
 {
-        unsigned long sum;
-#ifndef __s390x__
-        register_pair rp;
-
-        rp.subreg.even = (unsigned long) iph;
-        rp.subreg.odd = (unsigned long) ihl*4;
-        __asm__ __volatile__ (
-                "    sr   %0,%0\n"   /* set sum to zero */
-                "0:  cksm %0,%1\n"   /* do checksum on longs */
-                "    jo   0b\n"
-                : "=&d" (sum), "+&a" (rp) : : "cc", "memory" );
-#else /* __s390x__ */
-        __asm__ __volatile__ (
-                "    slgr %0,%0\n"   /* set sum to zero */
-                "    lgr  2,%1\n"    /* address in gpr 2 */
-                "    lgfr 3,%2\n"    /* length in gpr 3 */
-                "0:  cksm %0,2\n"    /* do checksum on ints */
-                "    jo   0b\n"
-                : "=&d" (sum)
-                : "d" (iph), "d" (ihl*4)
-                : "cc", "memory", "2", "3" );
-#endif /* __s390x__ */
-        return csum_fold(sum);
+        return csum_fold(csum_partial(iph, ihl*4, 0));
 }
 
 /*
@@ -190,47 +124,47 @@ csum_tcpudp_nofold(unsigned long saddr, unsigned long daddr,
                    unsigned int sum)
 {
 #ifndef __s390x__
-        __asm__ __volatile__ (
-                "    alr   %0,%1\n"  /* sum += saddr */
-                "    brc   12,0f\n"
-                "    ahi   %0,1\n"   /* add carry */
+        asm volatile(
+                "       alr     %0,%1\n" /* sum += saddr */
+                "       brc     12,0f\n"
+                "       ahi     %0,1\n"  /* add carry */
                 "0:"
-                : "+&d" (sum) : "d" (saddr) : "cc" );
-        __asm__ __volatile__ (
-                "    alr   %0,%1\n"  /* sum += daddr */
-                "    brc   12,1f\n"
-                "    ahi   %0,1\n"   /* add carry */
+                : "+&d" (sum) : "d" (saddr) : "cc");
+        asm volatile(
+                "       alr     %0,%1\n" /* sum += daddr */
+                "       brc     12,1f\n"
+                "       ahi     %0,1\n"  /* add carry */
                 "1:"
-                : "+&d" (sum) : "d" (daddr) : "cc" );
-        __asm__ __volatile__ (
-                "    alr   %0,%1\n"  /* sum += (len<<16) + (proto<<8) */
-                "    brc   12,2f\n"
-                "    ahi   %0,1\n"   /* add carry */
+                : "+&d" (sum) : "d" (daddr) : "cc");
+        asm volatile(
+                "       alr     %0,%1\n" /* sum += (len<<16) + (proto<<8) */
+                "       brc     12,2f\n"
+                "       ahi     %0,1\n"  /* add carry */
                 "2:"
                 : "+&d" (sum)
                 : "d" (((unsigned int) len<<16) + (unsigned int) proto)
-                : "cc" );
+                : "cc");
 #else /* __s390x__ */
-        __asm__ __volatile__ (
-                "    lgfr  %0,%0\n"
-                "    algr  %0,%1\n"  /* sum += saddr */
-                "    brc   12,0f\n"
-                "    aghi  %0,1\n"   /* add carry */
-                "0:  algr  %0,%2\n"  /* sum += daddr */
-                "    brc   12,1f\n"
-                "    aghi  %0,1\n"   /* add carry */
-                "1:  algfr %0,%3\n"  /* sum += (len<<16) + proto */
-                "    brc   12,2f\n"
-                "    aghi  %0,1\n"   /* add carry */
-                "2:  srlg  0,%0,32\n"
-                "    alr   %0,0\n"   /* fold to 32 bits */
-                "    brc   12,3f\n"
-                "    ahi   %0,1\n"   /* add carry */
-                "3:  llgfr %0,%0"
+        asm volatile(
+                "       lgfr    %0,%0\n"
+                "       algr    %0,%1\n"  /* sum += saddr */
+                "       brc     12,0f\n"
+                "       aghi    %0,1\n"   /* add carry */
+                "0:     algr    %0,%2\n"  /* sum += daddr */
+                "       brc     12,1f\n"
+                "       aghi    %0,1\n"   /* add carry */
+                "1:     algfr   %0,%3\n"  /* sum += (len<<16) + proto */
+                "       brc     12,2f\n"
+                "       aghi    %0,1\n"   /* add carry */
+                "2:     srlg    0,%0,32\n"
+                "       alr     %0,0\n"   /* fold to 32 bits */
+                "       brc     12,3f\n"
+                "       ahi     %0,1\n"   /* add carry */
+                "3:     llgfr   %0,%0"
                 : "+&d" (sum)
                 : "d" (saddr), "d" (daddr),
                   "d" (((unsigned int) len<<16) + (unsigned int) proto)
-                : "cc", "0" );
+                : "cc", "0");
 #endif /* __s390x__ */
         return sum;
 }