signal_64.c 19 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. #include "sigutil.h"
  35. #define _BLOCKABLE (~(sigmask(SIGKILL) | sigmask(SIGSTOP)))
  36. /* {set, get}context() needed for 64-bit SparcLinux userland. */
  37. asmlinkage void sparc64_set_context(struct pt_regs *regs)
  38. {
  39. struct ucontext __user *ucp = (struct ucontext __user *)
  40. regs->u_regs[UREG_I0];
  41. mc_gregset_t __user *grp;
  42. unsigned long pc, npc, tstate;
  43. unsigned long fp, i7;
  44. unsigned char fenab;
  45. int err;
  46. flush_user_windows();
  47. if (get_thread_wsaved() ||
  48. (((unsigned long)ucp) & (sizeof(unsigned long)-1)) ||
  49. (!__access_ok(ucp, sizeof(*ucp))))
  50. goto do_sigsegv;
  51. grp = &ucp->uc_mcontext.mc_gregs;
  52. err = __get_user(pc, &((*grp)[MC_PC]));
  53. err |= __get_user(npc, &((*grp)[MC_NPC]));
  54. if (err || ((pc | npc) & 3))
  55. goto do_sigsegv;
  56. if (regs->u_regs[UREG_I1]) {
  57. sigset_t set;
  58. if (_NSIG_WORDS == 1) {
  59. if (__get_user(set.sig[0], &ucp->uc_sigmask.sig[0]))
  60. goto do_sigsegv;
  61. } else {
  62. if (__copy_from_user(&set, &ucp->uc_sigmask, sizeof(sigset_t)))
  63. goto do_sigsegv;
  64. }
  65. sigdelsetmask(&set, ~_BLOCKABLE);
  66. spin_lock_irq(&current->sighand->siglock);
  67. current->blocked = set;
  68. recalc_sigpending();
  69. spin_unlock_irq(&current->sighand->siglock);
  70. }
  71. if (test_thread_flag(TIF_32BIT)) {
  72. pc &= 0xffffffff;
  73. npc &= 0xffffffff;
  74. }
  75. regs->tpc = pc;
  76. regs->tnpc = npc;
  77. err |= __get_user(regs->y, &((*grp)[MC_Y]));
  78. err |= __get_user(tstate, &((*grp)[MC_TSTATE]));
  79. regs->tstate &= ~(TSTATE_ASI | TSTATE_ICC | TSTATE_XCC);
  80. regs->tstate |= (tstate & (TSTATE_ASI | TSTATE_ICC | TSTATE_XCC));
  81. err |= __get_user(regs->u_regs[UREG_G1], (&(*grp)[MC_G1]));
  82. err |= __get_user(regs->u_regs[UREG_G2], (&(*grp)[MC_G2]));
  83. err |= __get_user(regs->u_regs[UREG_G3], (&(*grp)[MC_G3]));
  84. err |= __get_user(regs->u_regs[UREG_G4], (&(*grp)[MC_G4]));
  85. err |= __get_user(regs->u_regs[UREG_G5], (&(*grp)[MC_G5]));
  86. err |= __get_user(regs->u_regs[UREG_G6], (&(*grp)[MC_G6]));
  87. /* Skip %g7 as that's the thread register in userspace. */
  88. err |= __get_user(regs->u_regs[UREG_I0], (&(*grp)[MC_O0]));
  89. err |= __get_user(regs->u_regs[UREG_I1], (&(*grp)[MC_O1]));
  90. err |= __get_user(regs->u_regs[UREG_I2], (&(*grp)[MC_O2]));
  91. err |= __get_user(regs->u_regs[UREG_I3], (&(*grp)[MC_O3]));
  92. err |= __get_user(regs->u_regs[UREG_I4], (&(*grp)[MC_O4]));
  93. err |= __get_user(regs->u_regs[UREG_I5], (&(*grp)[MC_O5]));
  94. err |= __get_user(regs->u_regs[UREG_I6], (&(*grp)[MC_O6]));
  95. err |= __get_user(regs->u_regs[UREG_I7], (&(*grp)[MC_O7]));
  96. err |= __get_user(fp, &(ucp->uc_mcontext.mc_fp));
  97. err |= __get_user(i7, &(ucp->uc_mcontext.mc_i7));
  98. err |= __put_user(fp,
  99. (&(((struct reg_window __user *)(STACK_BIAS+regs->u_regs[UREG_I6]))->ins[6])));
  100. err |= __put_user(i7,
  101. (&(((struct reg_window __user *)(STACK_BIAS+regs->u_regs[UREG_I6]))->ins[7])));
  102. err |= __get_user(fenab, &(ucp->uc_mcontext.mc_fpregs.mcfpu_enab));
  103. if (fenab) {
  104. unsigned long *fpregs = current_thread_info()->fpregs;
  105. unsigned long fprs;
  106. fprs_write(0);
  107. err |= __get_user(fprs, &(ucp->uc_mcontext.mc_fpregs.mcfpu_fprs));
  108. if (fprs & FPRS_DL)
  109. err |= copy_from_user(fpregs,
  110. &(ucp->uc_mcontext.mc_fpregs.mcfpu_fregs),
  111. (sizeof(unsigned int) * 32));
  112. if (fprs & FPRS_DU)
  113. err |= copy_from_user(fpregs+16,
  114. ((unsigned long __user *)&(ucp->uc_mcontext.mc_fpregs.mcfpu_fregs))+16,
  115. (sizeof(unsigned int) * 32));
  116. err |= __get_user(current_thread_info()->xfsr[0],
  117. &(ucp->uc_mcontext.mc_fpregs.mcfpu_fsr));
  118. err |= __get_user(current_thread_info()->gsr[0],
  119. &(ucp->uc_mcontext.mc_fpregs.mcfpu_gsr));
  120. regs->tstate &= ~TSTATE_PEF;
  121. }
  122. if (err)
  123. goto do_sigsegv;
  124. return;
  125. do_sigsegv:
  126. force_sig(SIGSEGV, current);
  127. }
  128. asmlinkage void sparc64_get_context(struct pt_regs *regs)
  129. {
  130. struct ucontext __user *ucp = (struct ucontext __user *)
  131. regs->u_regs[UREG_I0];
  132. mc_gregset_t __user *grp;
  133. mcontext_t __user *mcp;
  134. unsigned long fp, i7;
  135. unsigned char fenab;
  136. int err;
  137. synchronize_user_stack();
  138. if (get_thread_wsaved() || clear_user(ucp, sizeof(*ucp)))
  139. goto do_sigsegv;
  140. #if 1
  141. fenab = 0; /* IMO get_context is like any other system call, thus modifies FPU state -jj */
  142. #else
  143. fenab = (current_thread_info()->fpsaved[0] & FPRS_FEF);
  144. #endif
  145. mcp = &ucp->uc_mcontext;
  146. grp = &mcp->mc_gregs;
  147. /* Skip over the trap instruction, first. */
  148. if (test_thread_flag(TIF_32BIT)) {
  149. regs->tpc = (regs->tnpc & 0xffffffff);
  150. regs->tnpc = (regs->tnpc + 4) & 0xffffffff;
  151. } else {
  152. regs->tpc = regs->tnpc;
  153. regs->tnpc += 4;
  154. }
  155. err = 0;
  156. if (_NSIG_WORDS == 1)
  157. err |= __put_user(current->blocked.sig[0],
  158. (unsigned long __user *)&ucp->uc_sigmask);
  159. else
  160. err |= __copy_to_user(&ucp->uc_sigmask, &current->blocked,
  161. sizeof(sigset_t));
  162. err |= __put_user(regs->tstate, &((*grp)[MC_TSTATE]));
  163. err |= __put_user(regs->tpc, &((*grp)[MC_PC]));
  164. err |= __put_user(regs->tnpc, &((*grp)[MC_NPC]));
  165. err |= __put_user(regs->y, &((*grp)[MC_Y]));
  166. err |= __put_user(regs->u_regs[UREG_G1], &((*grp)[MC_G1]));
  167. err |= __put_user(regs->u_regs[UREG_G2], &((*grp)[MC_G2]));
  168. err |= __put_user(regs->u_regs[UREG_G3], &((*grp)[MC_G3]));
  169. err |= __put_user(regs->u_regs[UREG_G4], &((*grp)[MC_G4]));
  170. err |= __put_user(regs->u_regs[UREG_G5], &((*grp)[MC_G5]));
  171. err |= __put_user(regs->u_regs[UREG_G6], &((*grp)[MC_G6]));
  172. err |= __put_user(regs->u_regs[UREG_G7], &((*grp)[MC_G7]));
  173. err |= __put_user(regs->u_regs[UREG_I0], &((*grp)[MC_O0]));
  174. err |= __put_user(regs->u_regs[UREG_I1], &((*grp)[MC_O1]));
  175. err |= __put_user(regs->u_regs[UREG_I2], &((*grp)[MC_O2]));
  176. err |= __put_user(regs->u_regs[UREG_I3], &((*grp)[MC_O3]));
  177. err |= __put_user(regs->u_regs[UREG_I4], &((*grp)[MC_O4]));
  178. err |= __put_user(regs->u_regs[UREG_I5], &((*grp)[MC_O5]));
  179. err |= __put_user(regs->u_regs[UREG_I6], &((*grp)[MC_O6]));
  180. err |= __put_user(regs->u_regs[UREG_I7], &((*grp)[MC_O7]));
  181. err |= __get_user(fp,
  182. (&(((struct reg_window __user *)(STACK_BIAS+regs->u_regs[UREG_I6]))->ins[6])));
  183. err |= __get_user(i7,
  184. (&(((struct reg_window __user *)(STACK_BIAS+regs->u_regs[UREG_I6]))->ins[7])));
  185. err |= __put_user(fp, &(mcp->mc_fp));
  186. err |= __put_user(i7, &(mcp->mc_i7));
  187. err |= __put_user(fenab, &(mcp->mc_fpregs.mcfpu_enab));
  188. if (fenab) {
  189. unsigned long *fpregs = current_thread_info()->fpregs;
  190. unsigned long fprs;
  191. fprs = current_thread_info()->fpsaved[0];
  192. if (fprs & FPRS_DL)
  193. err |= copy_to_user(&(mcp->mc_fpregs.mcfpu_fregs), fpregs,
  194. (sizeof(unsigned int) * 32));
  195. if (fprs & FPRS_DU)
  196. err |= copy_to_user(
  197. ((unsigned long __user *)&(mcp->mc_fpregs.mcfpu_fregs))+16, fpregs+16,
  198. (sizeof(unsigned int) * 32));
  199. err |= __put_user(current_thread_info()->xfsr[0], &(mcp->mc_fpregs.mcfpu_fsr));
  200. err |= __put_user(current_thread_info()->gsr[0], &(mcp->mc_fpregs.mcfpu_gsr));
  201. err |= __put_user(fprs, &(mcp->mc_fpregs.mcfpu_fprs));
  202. }
  203. if (err)
  204. goto do_sigsegv;
  205. return;
  206. do_sigsegv:
  207. force_sig(SIGSEGV, current);
  208. }
  209. struct rt_signal_frame {
  210. struct sparc_stackf ss;
  211. siginfo_t info;
  212. struct pt_regs regs;
  213. __siginfo_fpu_t __user *fpu_save;
  214. stack_t stack;
  215. sigset_t mask;
  216. __siginfo_rwin_t *rwin_save;
  217. };
  218. static long _sigpause_common(old_sigset_t set)
  219. {
  220. set &= _BLOCKABLE;
  221. spin_lock_irq(&current->sighand->siglock);
  222. current->saved_sigmask = current->blocked;
  223. siginitset(&current->blocked, set);
  224. recalc_sigpending();
  225. spin_unlock_irq(&current->sighand->siglock);
  226. current->state = TASK_INTERRUPTIBLE;
  227. schedule();
  228. set_restore_sigmask();
  229. return -ERESTARTNOHAND;
  230. }
  231. asmlinkage long sys_sigpause(unsigned int set)
  232. {
  233. return _sigpause_common(set);
  234. }
  235. asmlinkage long sys_sigsuspend(old_sigset_t set)
  236. {
  237. return _sigpause_common(set);
  238. }
  239. void do_rt_sigreturn(struct pt_regs *regs)
  240. {
  241. struct rt_signal_frame __user *sf;
  242. unsigned long tpc, tnpc, tstate;
  243. __siginfo_fpu_t __user *fpu_save;
  244. __siginfo_rwin_t __user *rwin_save;
  245. sigset_t set;
  246. int err;
  247. /* Always make any pending restarted system calls return -EINTR */
  248. current_thread_info()->restart_block.fn = do_no_restart_syscall;
  249. synchronize_user_stack ();
  250. sf = (struct rt_signal_frame __user *)
  251. (regs->u_regs [UREG_FP] + STACK_BIAS);
  252. /* 1. Make sure we are not getting garbage from the user */
  253. if (((unsigned long) sf) & 3)
  254. goto segv;
  255. err = get_user(tpc, &sf->regs.tpc);
  256. err |= __get_user(tnpc, &sf->regs.tnpc);
  257. if (test_thread_flag(TIF_32BIT)) {
  258. tpc &= 0xffffffff;
  259. tnpc &= 0xffffffff;
  260. }
  261. err |= ((tpc | tnpc) & 3);
  262. /* 2. Restore the state */
  263. err |= __get_user(regs->y, &sf->regs.y);
  264. err |= __get_user(tstate, &sf->regs.tstate);
  265. err |= copy_from_user(regs->u_regs, sf->regs.u_regs, sizeof(regs->u_regs));
  266. /* User can only change condition codes and %asi in %tstate. */
  267. regs->tstate &= ~(TSTATE_ASI | TSTATE_ICC | TSTATE_XCC);
  268. regs->tstate |= (tstate & (TSTATE_ASI | TSTATE_ICC | TSTATE_XCC));
  269. err |= __get_user(fpu_save, &sf->fpu_save);
  270. if (!err && fpu_save)
  271. err |= restore_fpu_state(regs, fpu_save);
  272. err |= __copy_from_user(&set, &sf->mask, sizeof(sigset_t));
  273. err |= do_sigaltstack(&sf->stack, NULL, (unsigned long)sf);
  274. if (err)
  275. goto segv;
  276. err |= __get_user(rwin_save, &sf->rwin_save);
  277. if (!err && rwin_save) {
  278. if (restore_rwin_state(rwin_save))
  279. goto segv;
  280. }
  281. regs->tpc = tpc;
  282. regs->tnpc = tnpc;
  283. /* Prevent syscall restart. */
  284. pt_regs_clear_syscall(regs);
  285. sigdelsetmask(&set, ~_BLOCKABLE);
  286. spin_lock_irq(&current->sighand->siglock);
  287. current->blocked = set;
  288. recalc_sigpending();
  289. spin_unlock_irq(&current->sighand->siglock);
  290. return;
  291. segv:
  292. force_sig(SIGSEGV, current);
  293. }
  294. /* Checks if the fp is valid */
  295. static int invalid_frame_pointer(void __user *fp)
  296. {
  297. if (((unsigned long) fp) & 15)
  298. return 1;
  299. return 0;
  300. }
  301. static inline void __user *get_sigframe(struct k_sigaction *ka, struct pt_regs *regs, unsigned long framesize)
  302. {
  303. unsigned long sp = regs->u_regs[UREG_FP] + STACK_BIAS;
  304. /*
  305. * If we are on the alternate signal stack and would overflow it, don't.
  306. * Return an always-bogus address instead so we will die with SIGSEGV.
  307. */
  308. if (on_sig_stack(sp) && !likely(on_sig_stack(sp - framesize)))
  309. return (void __user *) -1L;
  310. /* This is the X/Open sanctioned signal stack switching. */
  311. if (ka->sa.sa_flags & SA_ONSTACK) {
  312. if (sas_ss_flags(sp) == 0)
  313. sp = current->sas_ss_sp + current->sas_ss_size;
  314. }
  315. sp -= framesize;
  316. /* Always align the stack frame. This handles two cases. First,
  317. * sigaltstack need not be mindful of platform specific stack
  318. * alignment. Second, if we took this signal because the stack
  319. * is not aligned properly, we'd like to take the signal cleanly
  320. * and report that.
  321. */
  322. sp &= ~15UL;
  323. return (void __user *) sp;
  324. }
  325. static inline int
  326. setup_rt_frame(struct k_sigaction *ka, struct pt_regs *regs,
  327. int signo, sigset_t *oldset, siginfo_t *info)
  328. {
  329. struct rt_signal_frame __user *sf;
  330. int wsaved, err, sf_size;
  331. void __user *tail;
  332. /* 1. Make sure everything is clean */
  333. synchronize_user_stack();
  334. save_and_clear_fpu();
  335. wsaved = get_thread_wsaved();
  336. sf_size = sizeof(struct rt_signal_frame);
  337. if (current_thread_info()->fpsaved[0] & FPRS_FEF)
  338. sf_size += sizeof(__siginfo_fpu_t);
  339. if (wsaved)
  340. sf_size += sizeof(__siginfo_rwin_t);
  341. sf = (struct rt_signal_frame __user *)
  342. get_sigframe(ka, regs, sf_size);
  343. if (invalid_frame_pointer (sf))
  344. goto sigill;
  345. tail = (sf + 1);
  346. /* 2. Save the current process state */
  347. err = copy_to_user(&sf->regs, regs, sizeof (*regs));
  348. if (current_thread_info()->fpsaved[0] & FPRS_FEF) {
  349. __siginfo_fpu_t __user *fpu_save = tail;
  350. tail += sizeof(__siginfo_fpu_t);
  351. err |= save_fpu_state(regs, fpu_save);
  352. err |= __put_user((u64)fpu_save, &sf->fpu_save);
  353. } else {
  354. err |= __put_user(0, &sf->fpu_save);
  355. }
  356. if (wsaved) {
  357. __siginfo_rwin_t __user *rwin_save = tail;
  358. tail += sizeof(__siginfo_rwin_t);
  359. err |= save_rwin_state(wsaved, rwin_save);
  360. err |= __put_user((u64)rwin_save, &sf->rwin_save);
  361. set_thread_wsaved(0);
  362. } else {
  363. err |= __put_user(0, &sf->rwin_save);
  364. }
  365. /* Setup sigaltstack */
  366. err |= __put_user(current->sas_ss_sp, &sf->stack.ss_sp);
  367. err |= __put_user(sas_ss_flags(regs->u_regs[UREG_FP]), &sf->stack.ss_flags);
  368. err |= __put_user(current->sas_ss_size, &sf->stack.ss_size);
  369. err |= copy_to_user(&sf->mask, oldset, sizeof(sigset_t));
  370. if (!wsaved) {
  371. err |= copy_in_user((u64 __user *)sf,
  372. (u64 __user *)(regs->u_regs[UREG_FP] +
  373. STACK_BIAS),
  374. sizeof(struct reg_window));
  375. } else {
  376. struct reg_window *rp;
  377. rp = &current_thread_info()->reg_window[wsaved - 1];
  378. err |= copy_to_user(sf, rp, sizeof(struct reg_window));
  379. }
  380. if (info)
  381. err |= copy_siginfo_to_user(&sf->info, info);
  382. else {
  383. err |= __put_user(signo, &sf->info.si_signo);
  384. err |= __put_user(SI_NOINFO, &sf->info.si_code);
  385. }
  386. if (err)
  387. goto sigsegv;
  388. /* 3. signal handler back-trampoline and parameters */
  389. regs->u_regs[UREG_FP] = ((unsigned long) sf) - STACK_BIAS;
  390. regs->u_regs[UREG_I0] = signo;
  391. regs->u_regs[UREG_I1] = (unsigned long) &sf->info;
  392. /* The sigcontext is passed in this way because of how it
  393. * is defined in GLIBC's /usr/include/bits/sigcontext.h
  394. * for sparc64. It includes the 128 bytes of siginfo_t.
  395. */
  396. regs->u_regs[UREG_I2] = (unsigned long) &sf->info;
  397. /* 5. signal handler */
  398. regs->tpc = (unsigned long) ka->sa.sa_handler;
  399. regs->tnpc = (regs->tpc + 4);
  400. if (test_thread_flag(TIF_32BIT)) {
  401. regs->tpc &= 0xffffffff;
  402. regs->tnpc &= 0xffffffff;
  403. }
  404. /* 4. return to kernel instructions */
  405. regs->u_regs[UREG_I7] = (unsigned long)ka->ka_restorer;
  406. return 0;
  407. sigill:
  408. do_exit(SIGILL);
  409. return -EINVAL;
  410. sigsegv:
  411. force_sigsegv(signo, current);
  412. return -EFAULT;
  413. }
  414. static inline int handle_signal(unsigned long signr, struct k_sigaction *ka,
  415. siginfo_t *info,
  416. sigset_t *oldset, struct pt_regs *regs)
  417. {
  418. int err;
  419. err = setup_rt_frame(ka, regs, signr, oldset,
  420. (ka->sa.sa_flags & SA_SIGINFO) ? info : NULL);
  421. if (err)
  422. return err;
  423. spin_lock_irq(&current->sighand->siglock);
  424. sigorsets(&current->blocked,&current->blocked,&ka->sa.sa_mask);
  425. if (!(ka->sa.sa_flags & SA_NOMASK))
  426. sigaddset(&current->blocked,signr);
  427. recalc_sigpending();
  428. spin_unlock_irq(&current->sighand->siglock);
  429. tracehook_signal_handler(signr, info, ka, regs, 0);
  430. return 0;
  431. }
  432. static inline void syscall_restart(unsigned long orig_i0, struct pt_regs *regs,
  433. struct sigaction *sa)
  434. {
  435. switch (regs->u_regs[UREG_I0]) {
  436. case ERESTART_RESTARTBLOCK:
  437. case ERESTARTNOHAND:
  438. no_system_call_restart:
  439. regs->u_regs[UREG_I0] = EINTR;
  440. regs->tstate |= (TSTATE_ICARRY|TSTATE_XCARRY);
  441. break;
  442. case ERESTARTSYS:
  443. if (!(sa->sa_flags & SA_RESTART))
  444. goto no_system_call_restart;
  445. /* fallthrough */
  446. case ERESTARTNOINTR:
  447. regs->u_regs[UREG_I0] = orig_i0;
  448. regs->tpc -= 4;
  449. regs->tnpc -= 4;
  450. }
  451. }
  452. /* Note that 'init' is a special process: it doesn't get signals it doesn't
  453. * want to handle. Thus you cannot kill init even with a SIGKILL even by
  454. * mistake.
  455. */
  456. static void do_signal(struct pt_regs *regs, unsigned long orig_i0)
  457. {
  458. struct k_sigaction ka;
  459. int restart_syscall;
  460. sigset_t *oldset;
  461. siginfo_t info;
  462. int signr;
  463. /* It's a lot of work and synchronization to add a new ptrace
  464. * register for GDB to save and restore in order to get
  465. * orig_i0 correct for syscall restarts when debugging.
  466. *
  467. * Although it should be the case that most of the global
  468. * registers are volatile across a system call, glibc already
  469. * depends upon that fact that we preserve them. So we can't
  470. * just use any global register to save away the orig_i0 value.
  471. *
  472. * In particular %g2, %g3, %g4, and %g5 are all assumed to be
  473. * preserved across a system call trap by various pieces of
  474. * code in glibc.
  475. *
  476. * %g7 is used as the "thread register". %g6 is not used in
  477. * any fixed manner. %g6 is used as a scratch register and
  478. * a compiler temporary, but it's value is never used across
  479. * a system call. Therefore %g6 is usable for orig_i0 storage.
  480. */
  481. if (pt_regs_is_syscall(regs) &&
  482. (regs->tstate & (TSTATE_XCARRY | TSTATE_ICARRY)))
  483. regs->u_regs[UREG_G6] = orig_i0;
  484. if (current_thread_info()->status & TS_RESTORE_SIGMASK)
  485. oldset = &current->saved_sigmask;
  486. else
  487. oldset = &current->blocked;
  488. #ifdef CONFIG_COMPAT
  489. if (test_thread_flag(TIF_32BIT)) {
  490. extern void do_signal32(sigset_t *, struct pt_regs *);
  491. do_signal32(oldset, regs);
  492. return;
  493. }
  494. #endif
  495. signr = get_signal_to_deliver(&info, &ka, regs, NULL);
  496. restart_syscall = 0;
  497. if (pt_regs_is_syscall(regs) &&
  498. (regs->tstate & (TSTATE_XCARRY | TSTATE_ICARRY))) {
  499. restart_syscall = 1;
  500. orig_i0 = regs->u_regs[UREG_G6];
  501. }
  502. if (signr > 0) {
  503. if (restart_syscall)
  504. syscall_restart(orig_i0, regs, &ka.sa);
  505. if (handle_signal(signr, &ka, &info, oldset, regs) == 0) {
  506. /* A signal was successfully delivered; the saved
  507. * sigmask will have been stored in the signal frame,
  508. * and will be restored by sigreturn, so we can simply
  509. * clear the TS_RESTORE_SIGMASK flag.
  510. */
  511. current_thread_info()->status &= ~TS_RESTORE_SIGMASK;
  512. }
  513. return;
  514. }
  515. if (restart_syscall &&
  516. (regs->u_regs[UREG_I0] == ERESTARTNOHAND ||
  517. regs->u_regs[UREG_I0] == ERESTARTSYS ||
  518. regs->u_regs[UREG_I0] == ERESTARTNOINTR)) {
  519. /* replay the system call when we are done */
  520. regs->u_regs[UREG_I0] = orig_i0;
  521. regs->tpc -= 4;
  522. regs->tnpc -= 4;
  523. pt_regs_clear_syscall(regs);
  524. }
  525. if (restart_syscall &&
  526. regs->u_regs[UREG_I0] == ERESTART_RESTARTBLOCK) {
  527. regs->u_regs[UREG_G1] = __NR_restart_syscall;
  528. regs->tpc -= 4;
  529. regs->tnpc -= 4;
  530. pt_regs_clear_syscall(regs);
  531. }
  532. /* If there's no signal to deliver, we just put the saved sigmask
  533. * back
  534. */
  535. if (current_thread_info()->status & TS_RESTORE_SIGMASK) {
  536. current_thread_info()->status &= ~TS_RESTORE_SIGMASK;
  537. sigprocmask(SIG_SETMASK, &current->saved_sigmask, NULL);
  538. }
  539. }
  540. void do_notify_resume(struct pt_regs *regs, unsigned long orig_i0, unsigned long thread_info_flags)
  541. {
  542. if (thread_info_flags & _TIF_SIGPENDING)
  543. do_signal(regs, orig_i0);
  544. if (thread_info_flags & _TIF_NOTIFY_RESUME) {
  545. clear_thread_flag(TIF_NOTIFY_RESUME);
  546. tracehook_notify_resume(regs);
  547. if (current->replacement_session_keyring)
  548. key_replace_session_keyring();
  549. }
  550. }