My hacks to make the memory map fit

[Martin Cracauer]

Can as well copy it to the list.  This is what I have to do to make
the memory map, that means the placement of shared libraries and the
default place of mmap() calls come out the same way that it does on
Linux (where Linux = one where Fedora doesn't play with the maps).

1) apply appended diff (my version not limited to the Linux
   emulator).  Diff is against 5-stable, but same thing works on
   6-current

2) sysctl vm.cracauer_mmap_offset=402333696
   This introduces a default offset that moves the shared libs high
   enough.

However, ld-xxx.so is still in the way because it has hardcoded
addresses, so you need this:

3) get a `prelink` binary, I use the one from Redhat-9, works on
   linux_base-7 and linux_base-8

4) prelink -r 0x18000000 /compat/linux/lib/ld-2.3.2.so
   (or whatever ld-2.3.2.so you have)

This changes the memory map to what Linux program expect, see appended
example map.

It makes the Linux binary of CMUCL run, including C and C++ libraries
dynamically loaded from CMUCL :-)

I think that some of the problems I have running Cedega (commercial
version of Wine) or Wine itself are related to this.  Didn't test yet
whether this fixes it.

Martin
-- 
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
Martin Cracauer <cracauer at cons.org>   http://www.cons.org/cracauer/
 No warranty.    This email is probably produced by one of my cats 
 stepping on the keys. No, I don't have an infinite number of cats.
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Permission denied, please try again.
Permission denied, please try again.
Index: vm/vm_mmap.c
===================================================================
RCS file: /home/CVS-FreeBSD/src/sys/vm/vm_mmap.c,v
retrieving revision 1.192.2.2
diff -u -r1.192.2.2 vm_mmap.c
--- vm/vm_mmap.c	31 Jan 2005 23:27:03 -0000	1.192.2.2
+++ vm/vm_mmap.c	23 May 2005 16:47:54 -0000
@@ -88,6 +88,11 @@
 static int max_proc_mmap;
 SYSCTL_INT(_vm, OID_AUTO, max_proc_mmap, CTLFLAG_RW, &max_proc_mmap, 0, "");
 
+static vm_offset_t cracauer_mmap_offset;
+SYSCTL_INT(_vm, OID_AUTO, cracauer_mmap_offset, CTLFLAG_RW,
+	   &cracauer_mmap_offset, 0, "");
+
+
 /*
  * Set the maximum number of vm_map_entry structures per process.  Roughly
  * speaking vm_map_entry structures are tiny, so allowing them to eat 1/100
@@ -271,10 +276,12 @@
 		PROC_LOCK(td->td_proc);
 		if (addr == 0 ||
 		    (addr >= round_page((vm_offset_t)vms->vm_taddr) &&
-		    addr < round_page((vm_offset_t)vms->vm_daddr +
-		    lim_max(td->td_proc, RLIMIT_DATA))))
+			addr < round_page((vm_offset_t)vms->vm_daddr +
+			    lim_max(td->td_proc, RLIMIT_DATA)))) {
 			addr = round_page((vm_offset_t)vms->vm_daddr +
-			    lim_max(td->td_proc, RLIMIT_DATA));
+			    lim_max(td->td_proc, RLIMIT_DATA) +
+			    cracauer_mmap_offset);
+		}
 		PROC_UNLOCK(td->td_proc);
 	}
 	if (flags & MAP_ANON) {