system.h 7.4 KB

123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154155156157158159160161162163164165166167168169170171172173174175176177178179180181182183184185186187188189190191192193194195196197198199200201202203204205206207208209210211212213214215216217218219220221222223224225226227228229230231232233234235236237238239240241242243244245246247248249250251252253254255256257258259260261262263264265266267268269270271272273274275276277278279280281282283284285286287288289290291292293
  1. #ifndef __ASM_SYSTEM_H
  2. #define __ASM_SYSTEM_H
  3. #include <linux/kernel.h>
  4. #include <asm/segment.h>
  5. #include <asm/alternative.h>
  6. #ifdef __KERNEL__
  7. #define __STR(x) #x
  8. #define STR(x) __STR(x)
  9. #define __SAVE(reg,offset) "movq %%" #reg ",(14-" #offset ")*8(%%rsp)\n\t"
  10. #define __RESTORE(reg,offset) "movq (14-" #offset ")*8(%%rsp),%%" #reg "\n\t"
  11. /* frame pointer must be last for get_wchan */
  12. #define SAVE_CONTEXT "pushf ; pushq %%rbp ; movq %%rsi,%%rbp\n\t"
  13. #define RESTORE_CONTEXT "movq %%rbp,%%rsi ; popq %%rbp ; popf\t"
  14. #define __EXTRA_CLOBBER \
  15. ,"rcx","rbx","rdx","r8","r9","r10","r11","r12","r13","r14","r15"
  16. /* Save restore flags to clear handle leaking NT */
  17. #define switch_to(prev,next,last) \
  18. asm volatile(SAVE_CONTEXT \
  19. "movq %%rsp,%P[threadrsp](%[prev])\n\t" /* save RSP */ \
  20. "movq %P[threadrsp](%[next]),%%rsp\n\t" /* restore RSP */ \
  21. "call __switch_to\n\t" \
  22. ".globl thread_return\n" \
  23. "thread_return:\n\t" \
  24. "movq %%gs:%P[pda_pcurrent],%%rsi\n\t" \
  25. "movq %P[thread_info](%%rsi),%%r8\n\t" \
  26. LOCK_PREFIX "btr %[tif_fork],%P[ti_flags](%%r8)\n\t" \
  27. "movq %%rax,%%rdi\n\t" \
  28. "jc ret_from_fork\n\t" \
  29. RESTORE_CONTEXT \
  30. : "=a" (last) \
  31. : [next] "S" (next), [prev] "D" (prev), \
  32. [threadrsp] "i" (offsetof(struct task_struct, thread.rsp)), \
  33. [ti_flags] "i" (offsetof(struct thread_info, flags)),\
  34. [tif_fork] "i" (TIF_FORK), \
  35. [thread_info] "i" (offsetof(struct task_struct, thread_info)), \
  36. [pda_pcurrent] "i" (offsetof(struct x8664_pda, pcurrent)) \
  37. : "memory", "cc" __EXTRA_CLOBBER)
  38. extern void load_gs_index(unsigned);
  39. /*
  40. * Load a segment. Fall back on loading the zero
  41. * segment if something goes wrong..
  42. */
  43. #define loadsegment(seg,value) \
  44. asm volatile("\n" \
  45. "1:\t" \
  46. "movl %k0,%%" #seg "\n" \
  47. "2:\n" \
  48. ".section .fixup,\"ax\"\n" \
  49. "3:\t" \
  50. "movl %1,%%" #seg "\n\t" \
  51. "jmp 2b\n" \
  52. ".previous\n" \
  53. ".section __ex_table,\"a\"\n\t" \
  54. ".align 8\n\t" \
  55. ".quad 1b,3b\n" \
  56. ".previous" \
  57. : :"r" (value), "r" (0))
  58. /*
  59. * Clear and set 'TS' bit respectively
  60. */
  61. #define clts() __asm__ __volatile__ ("clts")
  62. static inline unsigned long read_cr0(void)
  63. {
  64. unsigned long cr0;
  65. asm volatile("movq %%cr0,%0" : "=r" (cr0));
  66. return cr0;
  67. }
  68. static inline void write_cr0(unsigned long val)
  69. {
  70. asm volatile("movq %0,%%cr0" :: "r" (val));
  71. }
  72. static inline unsigned long read_cr3(void)
  73. {
  74. unsigned long cr3;
  75. asm("movq %%cr3,%0" : "=r" (cr3));
  76. return cr3;
  77. }
  78. static inline void write_cr3(unsigned long val)
  79. {
  80. asm volatile("movq %0,%%cr3" :: "r" (val) : "memory");
  81. }
  82. static inline unsigned long read_cr4(void)
  83. {
  84. unsigned long cr4;
  85. asm("movq %%cr4,%0" : "=r" (cr4));
  86. return cr4;
  87. }
  88. static inline void write_cr4(unsigned long val)
  89. {
  90. asm volatile("movq %0,%%cr4" :: "r" (val) : "memory");
  91. }
  92. #define stts() write_cr0(8 | read_cr0())
  93. #define wbinvd() \
  94. __asm__ __volatile__ ("wbinvd": : :"memory");
  95. /*
  96. * On SMP systems, when the scheduler does migration-cost autodetection,
  97. * it needs a way to flush as much of the CPU's caches as possible.
  98. */
  99. static inline void sched_cacheflush(void)
  100. {
  101. wbinvd();
  102. }
  103. #endif /* __KERNEL__ */
  104. #define nop() __asm__ __volatile__ ("nop")
  105. #define xchg(ptr,v) ((__typeof__(*(ptr)))__xchg((unsigned long)(v),(ptr),sizeof(*(ptr))))
  106. #define __xg(x) ((volatile long *)(x))
  107. static inline void set_64bit(volatile unsigned long *ptr, unsigned long val)
  108. {
  109. *ptr = val;
  110. }
  111. #define _set_64bit set_64bit
  112. /*
  113. * Note: no "lock" prefix even on SMP: xchg always implies lock anyway
  114. * Note 2: xchg has side effect, so that attribute volatile is necessary,
  115. * but generally the primitive is invalid, *ptr is output argument. --ANK
  116. */
  117. static inline unsigned long __xchg(unsigned long x, volatile void * ptr, int size)
  118. {
  119. switch (size) {
  120. case 1:
  121. __asm__ __volatile__("xchgb %b0,%1"
  122. :"=q" (x)
  123. :"m" (*__xg(ptr)), "0" (x)
  124. :"memory");
  125. break;
  126. case 2:
  127. __asm__ __volatile__("xchgw %w0,%1"
  128. :"=r" (x)
  129. :"m" (*__xg(ptr)), "0" (x)
  130. :"memory");
  131. break;
  132. case 4:
  133. __asm__ __volatile__("xchgl %k0,%1"
  134. :"=r" (x)
  135. :"m" (*__xg(ptr)), "0" (x)
  136. :"memory");
  137. break;
  138. case 8:
  139. __asm__ __volatile__("xchgq %0,%1"
  140. :"=r" (x)
  141. :"m" (*__xg(ptr)), "0" (x)
  142. :"memory");
  143. break;
  144. }
  145. return x;
  146. }
  147. /*
  148. * Atomic compare and exchange. Compare OLD with MEM, if identical,
  149. * store NEW in MEM. Return the initial value in MEM. Success is
  150. * indicated by comparing RETURN with OLD.
  151. */
  152. #define __HAVE_ARCH_CMPXCHG 1
  153. static inline unsigned long __cmpxchg(volatile void *ptr, unsigned long old,
  154. unsigned long new, int size)
  155. {
  156. unsigned long prev;
  157. switch (size) {
  158. case 1:
  159. __asm__ __volatile__(LOCK_PREFIX "cmpxchgb %b1,%2"
  160. : "=a"(prev)
  161. : "q"(new), "m"(*__xg(ptr)), "0"(old)
  162. : "memory");
  163. return prev;
  164. case 2:
  165. __asm__ __volatile__(LOCK_PREFIX "cmpxchgw %w1,%2"
  166. : "=a"(prev)
  167. : "r"(new), "m"(*__xg(ptr)), "0"(old)
  168. : "memory");
  169. return prev;
  170. case 4:
  171. __asm__ __volatile__(LOCK_PREFIX "cmpxchgl %k1,%2"
  172. : "=a"(prev)
  173. : "r"(new), "m"(*__xg(ptr)), "0"(old)
  174. : "memory");
  175. return prev;
  176. case 8:
  177. __asm__ __volatile__(LOCK_PREFIX "cmpxchgq %1,%2"
  178. : "=a"(prev)
  179. : "r"(new), "m"(*__xg(ptr)), "0"(old)
  180. : "memory");
  181. return prev;
  182. }
  183. return old;
  184. }
  185. static inline unsigned long __cmpxchg_local(volatile void *ptr,
  186. unsigned long old, unsigned long new, int size)
  187. {
  188. unsigned long prev;
  189. switch (size) {
  190. case 1:
  191. __asm__ __volatile__("cmpxchgb %b1,%2"
  192. : "=a"(prev)
  193. : "q"(new), "m"(*__xg(ptr)), "0"(old)
  194. : "memory");
  195. return prev;
  196. case 2:
  197. __asm__ __volatile__("cmpxchgw %w1,%2"
  198. : "=a"(prev)
  199. : "r"(new), "m"(*__xg(ptr)), "0"(old)
  200. : "memory");
  201. return prev;
  202. case 4:
  203. __asm__ __volatile__("cmpxchgl %k1,%2"
  204. : "=a"(prev)
  205. : "r"(new), "m"(*__xg(ptr)), "0"(old)
  206. : "memory");
  207. return prev;
  208. case 8:
  209. __asm__ __volatile__("cmpxchgq %1,%2"
  210. : "=a"(prev)
  211. : "r"(new), "m"(*__xg(ptr)), "0"(old)
  212. : "memory");
  213. return prev;
  214. }
  215. return old;
  216. }
  217. #define cmpxchg(ptr,o,n)\
  218. ((__typeof__(*(ptr)))__cmpxchg((ptr),(unsigned long)(o),\
  219. (unsigned long)(n),sizeof(*(ptr))))
  220. #define cmpxchg_local(ptr,o,n)\
  221. ((__typeof__(*(ptr)))__cmpxchg((ptr),(unsigned long)(o),\
  222. (unsigned long)(n),sizeof(*(ptr))))
  223. #ifdef CONFIG_SMP
  224. #define smp_mb() mb()
  225. #define smp_rmb() rmb()
  226. #define smp_wmb() wmb()
  227. #define smp_read_barrier_depends() do {} while(0)
  228. #else
  229. #define smp_mb() barrier()
  230. #define smp_rmb() barrier()
  231. #define smp_wmb() barrier()
  232. #define smp_read_barrier_depends() do {} while(0)
  233. #endif
  234. /*
  235. * Force strict CPU ordering.
  236. * And yes, this is required on UP too when we're talking
  237. * to devices.
  238. */
  239. #define mb() asm volatile("mfence":::"memory")
  240. #define rmb() asm volatile("lfence":::"memory")
  241. #ifdef CONFIG_UNORDERED_IO
  242. #define wmb() asm volatile("sfence" ::: "memory")
  243. #else
  244. #define wmb() asm volatile("" ::: "memory")
  245. #endif
  246. #define read_barrier_depends() do {} while(0)
  247. #define set_mb(var, value) do { (void) xchg(&var, value); } while (0)
  248. #define warn_if_not_ulong(x) do { unsigned long foo; (void) (&(x) == &foo); } while (0)
  249. #include <linux/irqflags.h>
  250. void cpu_idle_wait(void);
  251. extern unsigned long arch_align_stack(unsigned long sp);
  252. extern void free_init_pages(char *what, unsigned long begin, unsigned long end);
  253. #endif