arch/metag/include/asm/user_gateway.h

   1 /*
   2  * Copyright (C) 2010 Imagination Technologies
   3  */
   4
   5 #ifndef __ASM_METAG_USER_GATEWAY_H
   6 #define __ASM_METAG_USER_GATEWAY_H
   7
   8 #include <asm/page.h>
   9
  10 /* Page of kernel code accessible to userspace. */
  11 #define USER_GATEWAY_PAGE       0x6ffff000
  12 /* Offset of TLS pointer array in gateway page. */
  13 #define USER_GATEWAY_TLS        0x100
  14
  15 #ifndef __ASSEMBLY__
  16
  17 extern char __user_gateway_start;
  18 extern char __user_gateway_end;
  19
  20 /* Kernel mapping of the gateway page. */
  21 extern void *gateway_page;
  22
  23 static inline void set_gateway_tls(void __user *tls_ptr)
  24 {
  25         void **gateway_tls = (void **)(gateway_page + USER_GATEWAY_TLS +
  26                                        hard_processor_id() * 4);
  27
  28         *gateway_tls = (__force void *)tls_ptr;
  29 #ifdef CONFIG_METAG_META12
  30         /* Avoid cache aliases on virtually tagged cache. */
  31         __builtin_dcache_flush((void *)USER_GATEWAY_PAGE + USER_GATEWAY_TLS +
  32                                        hard_processor_id() * sizeof(void *));
  33 #endif
  34 }
  35
  36 extern int __kuser_get_tls(void);
  37 extern char *__kuser_get_tls_end[];
  38
  39 extern int __kuser_cmpxchg(int, int, unsigned long *);
  40 extern char *__kuser_cmpxchg_end[];
  41
  42 #endif
  43
  44 #endif