signal_64.c 18 KB

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  1. /*
  2. * arch/sparc64/kernel/signal.c
  3. *
  4. * Copyright (C) 1991, 1992 Linus Torvalds
  5. * Copyright (C) 1995, 2008 David S. Miller (davem@davemloft.net)
  6. * Copyright (C) 1996 Miguel de Icaza (miguel@nuclecu.unam.mx)
  7. * Copyright (C) 1997 Eddie C. Dost (ecd@skynet.be)
  8. * Copyright (C) 1997,1998 Jakub Jelinek (jj@sunsite.mff.cuni.cz)
  9. */
  10. #ifdef CONFIG_COMPAT
  11. #include <linux/compat.h> /* for compat_old_sigset_t */
  12. #endif
  13. #include <linux/sched.h>
  14. #include <linux/kernel.h>
  15. #include <linux/signal.h>
  16. #include <linux/errno.h>
  17. #include <linux/wait.h>
  18. #include <linux/ptrace.h>
  19. #include <linux/tracehook.h>
  20. #include <linux/unistd.h>
  21. #include <linux/mm.h>
  22. #include <linux/tty.h>
  23. #include <linux/binfmts.h>
  24. #include <linux/bitops.h>
  25. #include <asm/uaccess.h>
  26. #include <asm/ptrace.h>
  27. #include <asm/pgtable.h>
  28. #include <asm/fpumacro.h>
  29. #include <asm/uctx.h>
  30. #include <asm/siginfo.h>
  31. #include <asm/visasm.h>
  32. #include "entry.h"
  33. #include "systbls.h"
  34. #define _BLOCKABLE (~(sigmask(SIGKILL) | sigmask(SIGSTOP)))
  35. /* {set, get}context() needed for 64-bit SparcLinux userland. */
  36. asmlinkage void sparc64_set_context(struct pt_regs *regs)
  37. {
  38. struct ucontext __user *ucp = (struct ucontext __user *)
  39. regs->u_regs[UREG_I0];
  40. mc_gregset_t __user *grp;
  41. unsigned long pc, npc, tstate;
  42. unsigned long fp, i7;
  43. unsigned char fenab;
  44. int err;
  45. flush_user_windows();
  46. if (get_thread_wsaved() ||
  47. (((unsigned long)ucp) & (sizeof(unsigned long)-1)) ||
  48. (!__access_ok(ucp, sizeof(*ucp))))
  49. goto do_sigsegv;
  50. grp = &ucp->uc_mcontext.mc_gregs;
  51. err = __get_user(pc, &((*grp)[MC_PC]));
  52. err |= __get_user(npc, &((*grp)[MC_NPC]));
  53. if (err || ((pc | npc) & 3))
  54. goto do_sigsegv;
  55. if (regs->u_regs[UREG_I1]) {
  56. sigset_t set;
  57. if (_NSIG_WORDS == 1) {
  58. if (__get_user(set.sig[0], &ucp->uc_sigmask.sig[0]))
  59. goto do_sigsegv;
  60. } else {
  61. if (__copy_from_user(&set, &ucp->uc_sigmask, sizeof(sigset_t)))
  62. goto do_sigsegv;
  63. }
  64. sigdelsetmask(&set, ~_BLOCKABLE);
  65. spin_lock_irq(&current->sighand->siglock);
  66. current->blocked = set;
  67. recalc_sigpending();
  68. spin_unlock_irq(&current->sighand->siglock);
  69. }
  70. if (test_thread_flag(TIF_32BIT)) {
  71. pc &= 0xffffffff;
  72. npc &= 0xffffffff;
  73. }
  74. regs->tpc = pc;
  75. regs->tnpc = npc;
  76. err |= __get_user(regs->y, &((*grp)[MC_Y]));
  77. err |= __get_user(tstate, &((*grp)[MC_TSTATE]));
  78. regs->tstate &= ~(TSTATE_ASI | TSTATE_ICC | TSTATE_XCC);
  79. regs->tstate |= (tstate & (TSTATE_ASI | TSTATE_ICC | TSTATE_XCC));
  80. err |= __get_user(regs->u_regs[UREG_G1], (&(*grp)[MC_G1]));
  81. err |= __get_user(regs->u_regs[UREG_G2], (&(*grp)[MC_G2]));
  82. err |= __get_user(regs->u_regs[UREG_G3], (&(*grp)[MC_G3]));
  83. err |= __get_user(regs->u_regs[UREG_G4], (&(*grp)[MC_G4]));
  84. err |= __get_user(regs->u_regs[UREG_G5], (&(*grp)[MC_G5]));
  85. err |= __get_user(regs->u_regs[UREG_G6], (&(*grp)[MC_G6]));
  86. /* Skip %g7 as that's the thread register in userspace. */
  87. err |= __get_user(regs->u_regs[UREG_I0], (&(*grp)[MC_O0]));
  88. err |= __get_user(regs->u_regs[UREG_I1], (&(*grp)[MC_O1]));
  89. err |= __get_user(regs->u_regs[UREG_I2], (&(*grp)[MC_O2]));
  90. err |= __get_user(regs->u_regs[UREG_I3], (&(*grp)[MC_O3]));
  91. err |= __get_user(regs->u_regs[UREG_I4], (&(*grp)[MC_O4]));
  92. err |= __get_user(regs->u_regs[UREG_I5], (&(*grp)[MC_O5]));
  93. err |= __get_user(regs->u_regs[UREG_I6], (&(*grp)[MC_O6]));
  94. err |= __get_user(regs->u_regs[UREG_I7], (&(*grp)[MC_O7]));
  95. err |= __get_user(fp, &(ucp->uc_mcontext.mc_fp));
  96. err |= __get_user(i7, &(ucp->uc_mcontext.mc_i7));
  97. err |= __put_user(fp,
  98. (&(((struct reg_window __user *)(STACK_BIAS+regs->u_regs[UREG_I6]))->ins[6])));
  99. err |= __put_user(i7,
  100. (&(((struct reg_window __user *)(STACK_BIAS+regs->u_regs[UREG_I6]))->ins[7])));
  101. err |= __get_user(fenab, &(ucp->uc_mcontext.mc_fpregs.mcfpu_enab));
  102. if (fenab) {
  103. unsigned long *fpregs = current_thread_info()->fpregs;
  104. unsigned long fprs;
  105. fprs_write(0);
  106. err |= __get_user(fprs, &(ucp->uc_mcontext.mc_fpregs.mcfpu_fprs));
  107. if (fprs & FPRS_DL)
  108. err |= copy_from_user(fpregs,
  109. &(ucp->uc_mcontext.mc_fpregs.mcfpu_fregs),
  110. (sizeof(unsigned int) * 32));
  111. if (fprs & FPRS_DU)
  112. err |= copy_from_user(fpregs+16,
  113. ((unsigned long __user *)&(ucp->uc_mcontext.mc_fpregs.mcfpu_fregs))+16,
  114. (sizeof(unsigned int) * 32));
  115. err |= __get_user(current_thread_info()->xfsr[0],
  116. &(ucp->uc_mcontext.mc_fpregs.mcfpu_fsr));
  117. err |= __get_user(current_thread_info()->gsr[0],
  118. &(ucp->uc_mcontext.mc_fpregs.mcfpu_gsr));
  119. regs->tstate &= ~TSTATE_PEF;
  120. }
  121. if (err)
  122. goto do_sigsegv;
  123. return;
  124. do_sigsegv:
  125. force_sig(SIGSEGV, current);
  126. }
  127. asmlinkage void sparc64_get_context(struct pt_regs *regs)
  128. {
  129. struct ucontext __user *ucp = (struct ucontext __user *)
  130. regs->u_regs[UREG_I0];
  131. mc_gregset_t __user *grp;
  132. mcontext_t __user *mcp;
  133. unsigned long fp, i7;
  134. unsigned char fenab;
  135. int err;
  136. synchronize_user_stack();
  137. if (get_thread_wsaved() || clear_user(ucp, sizeof(*ucp)))
  138. goto do_sigsegv;
  139. #if 1
  140. fenab = 0; /* IMO get_context is like any other system call, thus modifies FPU state -jj */
  141. #else
  142. fenab = (current_thread_info()->fpsaved[0] & FPRS_FEF);
  143. #endif
  144. mcp = &ucp->uc_mcontext;
  145. grp = &mcp->mc_gregs;
  146. /* Skip over the trap instruction, first. */
  147. if (test_thread_flag(TIF_32BIT)) {
  148. regs->tpc = (regs->tnpc & 0xffffffff);
  149. regs->tnpc = (regs->tnpc + 4) & 0xffffffff;
  150. } else {
  151. regs->tpc = regs->tnpc;
  152. regs->tnpc += 4;
  153. }
  154. err = 0;
  155. if (_NSIG_WORDS == 1)
  156. err |= __put_user(current->blocked.sig[0],
  157. (unsigned long __user *)&ucp->uc_sigmask);
  158. else
  159. err |= __copy_to_user(&ucp->uc_sigmask, &current->blocked,
  160. sizeof(sigset_t));
  161. err |= __put_user(regs->tstate, &((*grp)[MC_TSTATE]));
  162. err |= __put_user(regs->tpc, &((*grp)[MC_PC]));
  163. err |= __put_user(regs->tnpc, &((*grp)[MC_NPC]));
  164. err |= __put_user(regs->y, &((*grp)[MC_Y]));
  165. err |= __put_user(regs->u_regs[UREG_G1], &((*grp)[MC_G1]));
  166. err |= __put_user(regs->u_regs[UREG_G2], &((*grp)[MC_G2]));
  167. err |= __put_user(regs->u_regs[UREG_G3], &((*grp)[MC_G3]));
  168. err |= __put_user(regs->u_regs[UREG_G4], &((*grp)[MC_G4]));
  169. err |= __put_user(regs->u_regs[UREG_G5], &((*grp)[MC_G5]));
  170. err |= __put_user(regs->u_regs[UREG_G6], &((*grp)[MC_G6]));
  171. err |= __put_user(regs->u_regs[UREG_G7], &((*grp)[MC_G7]));
  172. err |= __put_user(regs->u_regs[UREG_I0], &((*grp)[MC_O0]));
  173. err |= __put_user(regs->u_regs[UREG_I1], &((*grp)[MC_O1]));
  174. err |= __put_user(regs->u_regs[UREG_I2], &((*grp)[MC_O2]));
  175. err |= __put_user(regs->u_regs[UREG_I3], &((*grp)[MC_O3]));
  176. err |= __put_user(regs->u_regs[UREG_I4], &((*grp)[MC_O4]));
  177. err |= __put_user(regs->u_regs[UREG_I5], &((*grp)[MC_O5]));
  178. err |= __put_user(regs->u_regs[UREG_I6], &((*grp)[MC_O6]));
  179. err |= __put_user(regs->u_regs[UREG_I7], &((*grp)[MC_O7]));
  180. err |= __get_user(fp,
  181. (&(((struct reg_window __user *)(STACK_BIAS+regs->u_regs[UREG_I6]))->ins[6])));
  182. err |= __get_user(i7,
  183. (&(((struct reg_window __user *)(STACK_BIAS+regs->u_regs[UREG_I6]))->ins[7])));
  184. err |= __put_user(fp, &(mcp->mc_fp));
  185. err |= __put_user(i7, &(mcp->mc_i7));
  186. err |= __put_user(fenab, &(mcp->mc_fpregs.mcfpu_enab));
  187. if (fenab) {
  188. unsigned long *fpregs = current_thread_info()->fpregs;
  189. unsigned long fprs;
  190. fprs = current_thread_info()->fpsaved[0];
  191. if (fprs & FPRS_DL)
  192. err |= copy_to_user(&(mcp->mc_fpregs.mcfpu_fregs), fpregs,
  193. (sizeof(unsigned int) * 32));
  194. if (fprs & FPRS_DU)
  195. err |= copy_to_user(
  196. ((unsigned long __user *)&(mcp->mc_fpregs.mcfpu_fregs))+16, fpregs+16,
  197. (sizeof(unsigned int) * 32));
  198. err |= __put_user(current_thread_info()->xfsr[0], &(mcp->mc_fpregs.mcfpu_fsr));
  199. err |= __put_user(current_thread_info()->gsr[0], &(mcp->mc_fpregs.mcfpu_gsr));
  200. err |= __put_user(fprs, &(mcp->mc_fpregs.mcfpu_fprs));
  201. }
  202. if (err)
  203. goto do_sigsegv;
  204. return;
  205. do_sigsegv:
  206. force_sig(SIGSEGV, current);
  207. }
  208. struct rt_signal_frame {
  209. struct sparc_stackf ss;
  210. siginfo_t info;
  211. struct pt_regs regs;
  212. __siginfo_fpu_t __user *fpu_save;
  213. stack_t stack;
  214. sigset_t mask;
  215. __siginfo_fpu_t fpu_state;
  216. };
  217. static long _sigpause_common(old_sigset_t set)
  218. {
  219. set &= _BLOCKABLE;
  220. spin_lock_irq(&current->sighand->siglock);
  221. current->saved_sigmask = current->blocked;
  222. siginitset(&current->blocked, set);
  223. recalc_sigpending();
  224. spin_unlock_irq(&current->sighand->siglock);
  225. current->state = TASK_INTERRUPTIBLE;
  226. schedule();
  227. set_restore_sigmask();
  228. return -ERESTARTNOHAND;
  229. }
  230. asmlinkage long sys_sigpause(unsigned int set)
  231. {
  232. return _sigpause_common(set);
  233. }
  234. asmlinkage long sys_sigsuspend(old_sigset_t set)
  235. {
  236. return _sigpause_common(set);
  237. }
  238. static inline int
  239. restore_fpu_state(struct pt_regs *regs, __siginfo_fpu_t __user *fpu)
  240. {
  241. unsigned long *fpregs = current_thread_info()->fpregs;
  242. unsigned long fprs;
  243. int err;
  244. err = __get_user(fprs, &fpu->si_fprs);
  245. fprs_write(0);
  246. regs->tstate &= ~TSTATE_PEF;
  247. if (fprs & FPRS_DL)
  248. err |= copy_from_user(fpregs, &fpu->si_float_regs[0],
  249. (sizeof(unsigned int) * 32));
  250. if (fprs & FPRS_DU)
  251. err |= copy_from_user(fpregs+16, &fpu->si_float_regs[32],
  252. (sizeof(unsigned int) * 32));
  253. err |= __get_user(current_thread_info()->xfsr[0], &fpu->si_fsr);
  254. err |= __get_user(current_thread_info()->gsr[0], &fpu->si_gsr);
  255. current_thread_info()->fpsaved[0] |= fprs;
  256. return err;
  257. }
  258. void do_rt_sigreturn(struct pt_regs *regs)
  259. {
  260. struct rt_signal_frame __user *sf;
  261. unsigned long tpc, tnpc, tstate;
  262. __siginfo_fpu_t __user *fpu_save;
  263. sigset_t set;
  264. int err;
  265. /* Always make any pending restarted system calls return -EINTR */
  266. current_thread_info()->restart_block.fn = do_no_restart_syscall;
  267. synchronize_user_stack ();
  268. sf = (struct rt_signal_frame __user *)
  269. (regs->u_regs [UREG_FP] + STACK_BIAS);
  270. /* 1. Make sure we are not getting garbage from the user */
  271. if (((unsigned long) sf) & 3)
  272. goto segv;
  273. err = get_user(tpc, &sf->regs.tpc);
  274. err |= __get_user(tnpc, &sf->regs.tnpc);
  275. if (test_thread_flag(TIF_32BIT)) {
  276. tpc &= 0xffffffff;
  277. tnpc &= 0xffffffff;
  278. }
  279. err |= ((tpc | tnpc) & 3);
  280. /* 2. Restore the state */
  281. err |= __get_user(regs->y, &sf->regs.y);
  282. err |= __get_user(tstate, &sf->regs.tstate);
  283. err |= copy_from_user(regs->u_regs, sf->regs.u_regs, sizeof(regs->u_regs));
  284. /* User can only change condition codes and %asi in %tstate. */
  285. regs->tstate &= ~(TSTATE_ASI | TSTATE_ICC | TSTATE_XCC);
  286. regs->tstate |= (tstate & (TSTATE_ASI | TSTATE_ICC | TSTATE_XCC));
  287. err |= __get_user(fpu_save, &sf->fpu_save);
  288. if (fpu_save)
  289. err |= restore_fpu_state(regs, &sf->fpu_state);
  290. err |= __copy_from_user(&set, &sf->mask, sizeof(sigset_t));
  291. err |= do_sigaltstack(&sf->stack, NULL, (unsigned long)sf);
  292. if (err)
  293. goto segv;
  294. regs->tpc = tpc;
  295. regs->tnpc = tnpc;
  296. /* Prevent syscall restart. */
  297. pt_regs_clear_syscall(regs);
  298. sigdelsetmask(&set, ~_BLOCKABLE);
  299. spin_lock_irq(&current->sighand->siglock);
  300. current->blocked = set;
  301. recalc_sigpending();
  302. spin_unlock_irq(&current->sighand->siglock);
  303. return;
  304. segv:
  305. force_sig(SIGSEGV, current);
  306. }
  307. /* Checks if the fp is valid */
  308. static int invalid_frame_pointer(void __user *fp, int fplen)
  309. {
  310. if (((unsigned long) fp) & 15)
  311. return 1;
  312. return 0;
  313. }
  314. static inline int
  315. save_fpu_state(struct pt_regs *regs, __siginfo_fpu_t __user *fpu)
  316. {
  317. unsigned long *fpregs = current_thread_info()->fpregs;
  318. unsigned long fprs;
  319. int err = 0;
  320. fprs = current_thread_info()->fpsaved[0];
  321. if (fprs & FPRS_DL)
  322. err |= copy_to_user(&fpu->si_float_regs[0], fpregs,
  323. (sizeof(unsigned int) * 32));
  324. if (fprs & FPRS_DU)
  325. err |= copy_to_user(&fpu->si_float_regs[32], fpregs+16,
  326. (sizeof(unsigned int) * 32));
  327. err |= __put_user(current_thread_info()->xfsr[0], &fpu->si_fsr);
  328. err |= __put_user(current_thread_info()->gsr[0], &fpu->si_gsr);
  329. err |= __put_user(fprs, &fpu->si_fprs);
  330. return err;
  331. }
  332. static inline void __user *get_sigframe(struct k_sigaction *ka, struct pt_regs *regs, unsigned long framesize)
  333. {
  334. unsigned long sp = regs->u_regs[UREG_FP] + STACK_BIAS;
  335. /*
  336. * If we are on the alternate signal stack and would overflow it, don't.
  337. * Return an always-bogus address instead so we will die with SIGSEGV.
  338. */
  339. if (on_sig_stack(sp) && !likely(on_sig_stack(sp - framesize)))
  340. return (void __user *) -1L;
  341. /* This is the X/Open sanctioned signal stack switching. */
  342. if (ka->sa.sa_flags & SA_ONSTACK) {
  343. if (sas_ss_flags(sp) == 0)
  344. sp = current->sas_ss_sp + current->sas_ss_size;
  345. }
  346. sp -= framesize;
  347. /* Always align the stack frame. This handles two cases. First,
  348. * sigaltstack need not be mindful of platform specific stack
  349. * alignment. Second, if we took this signal because the stack
  350. * is not aligned properly, we'd like to take the signal cleanly
  351. * and report that.
  352. */
  353. sp &= ~15UL;
  354. return (void __user *) sp;
  355. }
  356. static inline void
  357. setup_rt_frame(struct k_sigaction *ka, struct pt_regs *regs,
  358. int signo, sigset_t *oldset, siginfo_t *info)
  359. {
  360. struct rt_signal_frame __user *sf;
  361. int sigframe_size, err;
  362. /* 1. Make sure everything is clean */
  363. synchronize_user_stack();
  364. save_and_clear_fpu();
  365. sigframe_size = sizeof(struct rt_signal_frame);
  366. if (!(current_thread_info()->fpsaved[0] & FPRS_FEF))
  367. sigframe_size -= sizeof(__siginfo_fpu_t);
  368. sf = (struct rt_signal_frame __user *)
  369. get_sigframe(ka, regs, sigframe_size);
  370. if (invalid_frame_pointer (sf, sigframe_size))
  371. goto sigill;
  372. if (get_thread_wsaved() != 0)
  373. goto sigill;
  374. /* 2. Save the current process state */
  375. err = copy_to_user(&sf->regs, regs, sizeof (*regs));
  376. if (current_thread_info()->fpsaved[0] & FPRS_FEF) {
  377. err |= save_fpu_state(regs, &sf->fpu_state);
  378. err |= __put_user((u64)&sf->fpu_state, &sf->fpu_save);
  379. } else {
  380. err |= __put_user(0, &sf->fpu_save);
  381. }
  382. /* Setup sigaltstack */
  383. err |= __put_user(current->sas_ss_sp, &sf->stack.ss_sp);
  384. err |= __put_user(sas_ss_flags(regs->u_regs[UREG_FP]), &sf->stack.ss_flags);
  385. err |= __put_user(current->sas_ss_size, &sf->stack.ss_size);
  386. err |= copy_to_user(&sf->mask, oldset, sizeof(sigset_t));
  387. err |= copy_in_user((u64 __user *)sf,
  388. (u64 __user *)(regs->u_regs[UREG_FP]+STACK_BIAS),
  389. sizeof(struct reg_window));
  390. if (info)
  391. err |= copy_siginfo_to_user(&sf->info, info);
  392. else {
  393. err |= __put_user(signo, &sf->info.si_signo);
  394. err |= __put_user(SI_NOINFO, &sf->info.si_code);
  395. }
  396. if (err)
  397. goto sigsegv;
  398. /* 3. signal handler back-trampoline and parameters */
  399. regs->u_regs[UREG_FP] = ((unsigned long) sf) - STACK_BIAS;
  400. regs->u_regs[UREG_I0] = signo;
  401. regs->u_regs[UREG_I1] = (unsigned long) &sf->info;
  402. /* The sigcontext is passed in this way because of how it
  403. * is defined in GLIBC's /usr/include/bits/sigcontext.h
  404. * for sparc64. It includes the 128 bytes of siginfo_t.
  405. */
  406. regs->u_regs[UREG_I2] = (unsigned long) &sf->info;
  407. /* 5. signal handler */
  408. regs->tpc = (unsigned long) ka->sa.sa_handler;
  409. regs->tnpc = (regs->tpc + 4);
  410. if (test_thread_flag(TIF_32BIT)) {
  411. regs->tpc &= 0xffffffff;
  412. regs->tnpc &= 0xffffffff;
  413. }
  414. /* 4. return to kernel instructions */
  415. regs->u_regs[UREG_I7] = (unsigned long)ka->ka_restorer;
  416. return;
  417. sigill:
  418. do_exit(SIGILL);
  419. sigsegv:
  420. force_sigsegv(signo, current);
  421. }
  422. static inline void handle_signal(unsigned long signr, struct k_sigaction *ka,
  423. siginfo_t *info,
  424. sigset_t *oldset, struct pt_regs *regs)
  425. {
  426. setup_rt_frame(ka, regs, signr, oldset,
  427. (ka->sa.sa_flags & SA_SIGINFO) ? info : NULL);
  428. spin_lock_irq(&current->sighand->siglock);
  429. sigorsets(&current->blocked,&current->blocked,&ka->sa.sa_mask);
  430. if (!(ka->sa.sa_flags & SA_NOMASK))
  431. sigaddset(&current->blocked,signr);
  432. recalc_sigpending();
  433. spin_unlock_irq(&current->sighand->siglock);
  434. }
  435. static inline void syscall_restart(unsigned long orig_i0, struct pt_regs *regs,
  436. struct sigaction *sa)
  437. {
  438. switch (regs->u_regs[UREG_I0]) {
  439. case ERESTART_RESTARTBLOCK:
  440. case ERESTARTNOHAND:
  441. no_system_call_restart:
  442. regs->u_regs[UREG_I0] = EINTR;
  443. regs->tstate |= (TSTATE_ICARRY|TSTATE_XCARRY);
  444. break;
  445. case ERESTARTSYS:
  446. if (!(sa->sa_flags & SA_RESTART))
  447. goto no_system_call_restart;
  448. /* fallthrough */
  449. case ERESTARTNOINTR:
  450. regs->u_regs[UREG_I0] = orig_i0;
  451. regs->tpc -= 4;
  452. regs->tnpc -= 4;
  453. }
  454. }
  455. /* Note that 'init' is a special process: it doesn't get signals it doesn't
  456. * want to handle. Thus you cannot kill init even with a SIGKILL even by
  457. * mistake.
  458. */
  459. static void do_signal(struct pt_regs *regs, unsigned long orig_i0)
  460. {
  461. struct k_sigaction ka;
  462. int restart_syscall;
  463. sigset_t *oldset;
  464. siginfo_t info;
  465. int signr;
  466. if (pt_regs_is_syscall(regs) &&
  467. (regs->tstate & (TSTATE_XCARRY | TSTATE_ICARRY))) {
  468. restart_syscall = 1;
  469. } else
  470. restart_syscall = 0;
  471. if (current_thread_info()->status & TS_RESTORE_SIGMASK)
  472. oldset = &current->saved_sigmask;
  473. else
  474. oldset = &current->blocked;
  475. #ifdef CONFIG_COMPAT
  476. if (test_thread_flag(TIF_32BIT)) {
  477. extern void do_signal32(sigset_t *, struct pt_regs *,
  478. int restart_syscall,
  479. unsigned long orig_i0);
  480. do_signal32(oldset, regs, restart_syscall, orig_i0);
  481. return;
  482. }
  483. #endif
  484. signr = get_signal_to_deliver(&info, &ka, regs, NULL);
  485. /* If the debugger messes with the program counter, it clears
  486. * the software "in syscall" bit, directing us to not perform
  487. * a syscall restart.
  488. */
  489. if (restart_syscall && !pt_regs_is_syscall(regs))
  490. restart_syscall = 0;
  491. if (signr > 0) {
  492. if (restart_syscall)
  493. syscall_restart(orig_i0, regs, &ka.sa);
  494. handle_signal(signr, &ka, &info, oldset, regs);
  495. /* A signal was successfully delivered; the saved
  496. * sigmask will have been stored in the signal frame,
  497. * and will be restored by sigreturn, so we can simply
  498. * clear the TS_RESTORE_SIGMASK flag.
  499. */
  500. current_thread_info()->status &= ~TS_RESTORE_SIGMASK;
  501. tracehook_signal_handler(signr, &info, &ka, regs, 0);
  502. return;
  503. }
  504. if (restart_syscall &&
  505. (regs->u_regs[UREG_I0] == ERESTARTNOHAND ||
  506. regs->u_regs[UREG_I0] == ERESTARTSYS ||
  507. regs->u_regs[UREG_I0] == ERESTARTNOINTR)) {
  508. /* replay the system call when we are done */
  509. regs->u_regs[UREG_I0] = orig_i0;
  510. regs->tpc -= 4;
  511. regs->tnpc -= 4;
  512. }
  513. if (restart_syscall &&
  514. regs->u_regs[UREG_I0] == ERESTART_RESTARTBLOCK) {
  515. regs->u_regs[UREG_G1] = __NR_restart_syscall;
  516. regs->tpc -= 4;
  517. regs->tnpc -= 4;
  518. }
  519. /* If there's no signal to deliver, we just put the saved sigmask
  520. * back
  521. */
  522. if (current_thread_info()->status & TS_RESTORE_SIGMASK) {
  523. current_thread_info()->status &= ~TS_RESTORE_SIGMASK;
  524. sigprocmask(SIG_SETMASK, &current->saved_sigmask, NULL);
  525. }
  526. }
  527. void do_notify_resume(struct pt_regs *regs, unsigned long orig_i0, unsigned long thread_info_flags)
  528. {
  529. if (thread_info_flags & _TIF_SIGPENDING)
  530. do_signal(regs, orig_i0);
  531. if (thread_info_flags & _TIF_NOTIFY_RESUME) {
  532. clear_thread_flag(TIF_NOTIFY_RESUME);
  533. tracehook_notify_resume(regs);
  534. if (current->replacement_session_keyring)
  535. key_replace_session_keyring();
  536. }
  537. }