Patch to allow ARM dynamic linker to fix up PC24 relocs...

[Scott Bambrough <scottb@netwinder.org>]

The attached patch adds a cache flush just after the readonly protection
is restored to .text.  I've done this in generic code, because the cache
flush is an extremely expensive operation on the ARM.  We don't want to
do this after every fixup, and only if we do fixups.  The patch as
written should only affect the ARM (or anyone else who defines
CLEAR_CACHE).  For all other targets it will disappear after
pre-processing.  This patch has the fix for the problem Phil Blundell
pointed out.  I've tested it and it seems to work.

1999-12-21  Scott Bambrough  <scottb@netwinder.org>

        * sysdeps/arm/dl-machine.h (CLEAR_CACHE): New macro to force a
        cache flush.
        * elf/dl-reloc.c (_dl_relocate_object): Add call to flush cache
        after .text segment fixups.

Scott

-- 
Scott Bambrough - Software Engineer
REBEL.COM    http://www.rebel.com
NetWinder    http://www.netwinder.org
diff -upr glibc-2.1.2.orig/elf/dl-reloc.c glibc-2.1.2/elf/dl-reloc.c
--- glibc-2.1.2.orig/elf/dl-reloc.c	Sat Feb 20 09:45:53 1999
+++ glibc-2.1.2/elf/dl-reloc.c	Fri Dec 10 10:36:33 1999
@@ -126,6 +126,10 @@ _dl_relocate_object (struct link_map *l,
 	    if (__mprotect (mapstart, mapend - mapstart, prot) < 0)
 	      _dl_signal_error (errno, l->l_name,
 				"can't restore segment prot after reloc");
+
+#ifdef CLEAR_CACHE
+	    CLEAR_CACHE (mapstart, mapend);
+#endif 
 	  }
     }
 }
diff -upr glibc-2.1.2.orig/sysdeps/arm/dl-machine.h glibc-2.1.2/sysdeps/arm/dl-machine.h
--- glibc-2.1.2.orig/sysdeps/arm/dl-machine.h	Tue Aug 10 01:13:22 1999
+++ glibc-2.1.2/sysdeps/arm/dl-machine.h	Fri Dec 10 10:36:57 1999
@@ -35,6 +35,14 @@
   VALID_ELF_ABIVERSION(hdr[EI_ABIVERSION]) \
 )
 
+#define CLEAR_CACHE(BEG,END)						\
+{									\
+  register unsigned long _beg __asm ("a1") = (unsigned long)(BEG);	\
+  register unsigned long _end __asm ("a2") = (unsigned long)(END);	\
+  register unsigned long _flg __asm ("a3") = 0;			\
+  __asm __volatile ("swi 0x9f0002");					\
+}
+
 /* Return nonzero iff E_MACHINE is compatible with the running host.  */
 static inline int __attribute__ ((unused))
 elf_machine_matches_host (Elf32_Half e_machine)