linux/arch/um/sys-x86_64/unmap.c
Paolo 'Blaisorblade' Giarrusso 60b2737de1 [PATCH] uml: fix linkage of tt mode against NPTL
With Al Viro <viro@parcelfarce.linux.theplanet.co.uk>

To make sure switcheroo() can execute when we remap all the executable
image, we used a trick to make it use a local copy of errno...  this trick
does not work with NPTL glibc, only with LinuxThreads, so use another
(simpler) one to make it work anyway.

Hopefully, a lot improved thanks to merging with the version of Al Viro
(which had his part of problems, though, i.e.  removing a fix to another
bug and not fixing the problem on i386).

Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-21 19:07:32 -07:00

26 lines
564 B
C

/*
* Copyright (C) 2000 Jeff Dike (jdike@karaya.com)
* Licensed under the GPL
*/
#include <linux/mman.h>
#include <asm/unistd.h>
static int errno;
static inline _syscall2(int,munmap,void *,start,size_t,len)
static inline _syscall6(void *,mmap,void *,addr,size_t,len,int,prot,int,flags,int,fd,off_t,offset)
int switcheroo(int fd, int prot, void *from, void *to, int size)
{
if(munmap(to, size) < 0){
return(-1);
}
if(mmap(to, size, prot, MAP_SHARED | MAP_FIXED, fd, 0) != to){
return(-1);
}
if(munmap(from, size) < 0){
return(-1);
}
return(0);
}