Commit 5d90cf6d authored by Johannes Berg's avatar Johannes Berg Committed by Richard Weinberger
Browse files

um: further clean up user_syms 



Make some cleanups, add and fix some comments and document
here that we shouldn't export (libc) symbols for "_user.c"
code, rather such should work like hostfs does now.

Signed-off-by: default avatarJohannes Berg <johannes.berg@intel.com>
Signed-off-by: default avatarRichard Weinberger <richard@nod.at>
parent 6d708d1a

arch/um/os-Linux/user_syms.c

+16 −15
Original line number Diff line number Diff line
@@ -3,35 +3,36 @@ 
#include <linux/types.h>

#include <linux/module.h>



/* Some of this are builtin function (some are not but could in the future),

 * so I *must* declare good prototypes for them and then EXPORT them.

 * The kernel code uses the macro defined by include/linux/string.h,

 * so I undef macros; the userspace code does not include that and I

 * add an EXPORT for the glibc one.

/*

 * This file exports some critical string functions and compiler

 * built-in functions (where calls are emitted by the compiler

 * itself that we cannot avoid even in kernel code) to modules.

 *

 * "_user.c" code that previously used exports here such as hostfs

 * really should be considered part of the 'hypervisor' and define

 * its own API boundary like hostfs does now; don't add exports to

 * this file for such cases.

 */



#undef strlen

#undef strstr

#undef memcpy

#undef memset



extern size_t strlen(const char *);

extern void *memmove(void *, const void *, size_t);

extern void *memset(void *, int, size_t);



/* If it's not defined, the export is included in lib/string.c.*/

#ifdef __HAVE_ARCH_STRSTR

#undef strstr

EXPORT_SYMBOL(strstr);

#endif



#ifndef __x86_64__

#undef memcpy

extern void *memcpy(void *, const void *, size_t);

EXPORT_SYMBOL(memcpy);

extern void *memmove(void *, const void *, size_t);

EXPORT_SYMBOL(memmove);

#undef memset

extern void *memset(void *, int, size_t);

EXPORT_SYMBOL(memset);

#endif



#ifdef CONFIG_ARCH_REUSE_HOST_VSYSCALL_AREA

/* needed for __access_ok() */

EXPORT_SYMBOL(vsyscall_ehdr);

EXPORT_SYMBOL(vsyscall_end);

#endif
@@ -44,6 +45,6 @@ extern long __guard __attribute__((weak)); 
EXPORT_SYMBOL(__guard);



#ifdef _FORTIFY_SOURCE

extern int __sprintf_chk(char *str, int flag, size_t strlen, const char *format);

extern int __sprintf_chk(char *str, int flag, size_t len, const char *format);

EXPORT_SYMBOL(__sprintf_chk);

#endif