diff options
author | Paul Mundt <lethal@linux-sh.org> | 2007-11-10 20:07:57 +0900 |
---|---|---|
committer | Paul Mundt <lethal@linux-sh.org> | 2008-01-28 13:18:43 +0900 |
commit | f7a7b15344e2bccdd1c73d42685edfe7d43ec5b7 (patch) | |
tree | 87280639daf814c9a818994926785faf9daded88 /arch/sh64/kernel | |
parent | 76168c21b78a0bd684d4687d14a2bd76bcf92762 (diff) |
sh: Move in the SH-5 signal trampoline impl.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Diffstat (limited to 'arch/sh64/kernel')
-rw-r--r-- | arch/sh64/kernel/signal.c | 750 |
1 files changed, 0 insertions, 750 deletions
diff --git a/arch/sh64/kernel/signal.c b/arch/sh64/kernel/signal.c deleted file mode 100644 index 79fc48cf54c..00000000000 --- a/arch/sh64/kernel/signal.c +++ /dev/null @@ -1,750 +0,0 @@ -/* - * This file is subject to the terms and conditions of the GNU General Public - * License. See the file "COPYING" in the main directory of this archive - * for more details. - * - * arch/sh64/kernel/signal.c - * - * Copyright (C) 2000, 2001 Paolo Alberelli - * Copyright (C) 2003 Paul Mundt - * Copyright (C) 2004 Richard Curnow - * - * Started from sh version. - * - */ -#include <linux/rwsem.h> -#include <linux/sched.h> -#include <linux/mm.h> -#include <linux/smp.h> -#include <linux/kernel.h> -#include <linux/signal.h> -#include <linux/errno.h> -#include <linux/wait.h> -#include <linux/personality.h> -#include <linux/freezer.h> -#include <linux/ptrace.h> -#include <linux/unistd.h> -#include <linux/stddef.h> -#include <asm/ucontext.h> -#include <asm/uaccess.h> -#include <asm/pgtable.h> - - -#define REG_RET 9 -#define REG_ARG1 2 -#define REG_ARG2 3 -#define REG_ARG3 4 -#define REG_SP 15 -#define REG_PR 18 -#define REF_REG_RET regs->regs[REG_RET] -#define REF_REG_SP regs->regs[REG_SP] -#define DEREF_REG_PR regs->regs[REG_PR] - -#define DEBUG_SIG 0 - -#define _BLOCKABLE (~(sigmask(SIGKILL) | sigmask(SIGSTOP))) - -asmlinkage int do_signal(struct pt_regs *regs, sigset_t *oldset); - -/* - * Atomically swap in the new signal mask, and wait for a signal. - */ - -asmlinkage int -sys_sigsuspend(old_sigset_t mask, - unsigned long r3, unsigned long r4, unsigned long r5, - unsigned long r6, unsigned long r7, - struct pt_regs * regs) -{ - sigset_t saveset; - - mask &= _BLOCKABLE; - spin_lock_irq(¤t->sighand->siglock); - saveset = current->blocked; - siginitset(¤t->blocked, mask); - recalc_sigpending(); - spin_unlock_irq(¤t->sighand->siglock); - - REF_REG_RET = -EINTR; - while (1) { - current->state = TASK_INTERRUPTIBLE; - schedule(); - regs->pc += 4; /* because sys_sigreturn decrements the pc */ - if (do_signal(regs, &saveset)) { - /* pc now points at signal handler. Need to decrement - it because entry.S will increment it. */ - regs->pc -= 4; - return -EINTR; - } - } -} - -asmlinkage int -sys_rt_sigsuspend(sigset_t *unewset, size_t sigsetsize, - unsigned long r4, unsigned long r5, unsigned long r6, - unsigned long r7, - struct pt_regs * regs) -{ - sigset_t saveset, newset; - - /* XXX: Don't preclude handling different sized sigset_t's. */ - if (sigsetsize != sizeof(sigset_t)) - return -EINVAL; - - if (copy_from_user(&newset, unewset, sizeof(newset))) - return -EFAULT; - sigdelsetmask(&newset, ~_BLOCKABLE); - spin_lock_irq(¤t->sighand->siglock); - saveset = current->blocked; - current->blocked = newset; - recalc_sigpending(); - spin_unlock_irq(¤t->sighand->siglock); - - REF_REG_RET = -EINTR; - while (1) { - current->state = TASK_INTERRUPTIBLE; - schedule(); - regs->pc += 4; /* because sys_sigreturn decrements the pc */ - if (do_signal(regs, &saveset)) { - /* pc now points at signal handler. Need to decrement - it because entry.S will increment it. */ - regs->pc -= 4; - return -EINTR; - } - } -} - -asmlinkage int -sys_sigaction(int sig, const struct old_sigaction __user *act, - struct old_sigaction __user *oact) -{ - struct k_sigaction new_ka, old_ka; - int ret; - - if (act) { - old_sigset_t mask; - if (!access_ok(VERIFY_READ, act, sizeof(*act)) || - __get_user(new_ka.sa.sa_handler, &act->sa_handler) || - __get_user(new_ka.sa.sa_restorer, &act->sa_restorer)) - return -EFAULT; - __get_user(new_ka.sa.sa_flags, &act->sa_flags); - __get_user(mask, &act->sa_mask); - siginitset(&new_ka.sa.sa_mask, mask); - } - - ret = do_sigaction(sig, act ? &new_ka : NULL, oact ? &old_ka : NULL); - - if (!ret && oact) { - if (!access_ok(VERIFY_WRITE, oact, sizeof(*oact)) || - __put_user(old_ka.sa.sa_handler, &oact->sa_handler) || - __put_user(old_ka.sa.sa_restorer, &oact->sa_restorer)) - return -EFAULT; - __put_user(old_ka.sa.sa_flags, &oact->sa_flags); - __put_user(old_ka.sa.sa_mask.sig[0], &oact->sa_mask); - } - - return ret; -} - -asmlinkage int -sys_sigaltstack(const stack_t __user *uss, stack_t __user *uoss, - unsigned long r4, unsigned long r5, unsigned long r6, - unsigned long r7, - struct pt_regs * regs) -{ - return do_sigaltstack(uss, uoss, REF_REG_SP); -} - - -/* - * Do a signal return; undo the signal stack. - */ - -struct sigframe -{ - struct sigcontext sc; - unsigned long extramask[_NSIG_WORDS-1]; - long long retcode[2]; -}; - -struct rt_sigframe -{ - struct siginfo __user *pinfo; - void *puc; - struct siginfo info; - struct ucontext uc; - long long retcode[2]; -}; - -#ifdef CONFIG_SH_FPU -static inline int -restore_sigcontext_fpu(struct pt_regs *regs, struct sigcontext __user *sc) -{ - int err = 0; - int fpvalid; - - err |= __get_user (fpvalid, &sc->sc_fpvalid); - conditional_used_math(fpvalid); - if (! fpvalid) - return err; - - if (current == last_task_used_math) { - last_task_used_math = NULL; - regs->sr |= SR_FD; - } - - err |= __copy_from_user(¤t->thread.fpu.hard, &sc->sc_fpregs[0], - (sizeof(long long) * 32) + (sizeof(int) * 1)); - - return err; -} - -static inline int -setup_sigcontext_fpu(struct pt_regs *regs, struct sigcontext __user *sc) -{ - int err = 0; - int fpvalid; - - fpvalid = !!used_math(); - err |= __put_user(fpvalid, &sc->sc_fpvalid); - if (! fpvalid) - return err; - - if (current == last_task_used_math) { - grab_fpu(); - fpsave(¤t->thread.fpu.hard); - release_fpu(); - last_task_used_math = NULL; - regs->sr |= SR_FD; - } - - err |= __copy_to_user(&sc->sc_fpregs[0], ¤t->thread.fpu.hard, - (sizeof(long long) * 32) + (sizeof(int) * 1)); - clear_used_math(); - - return err; -} -#else -static inline int -restore_sigcontext_fpu(struct pt_regs *regs, struct sigcontext __user *sc) -{} -static inline int -setup_sigcontext_fpu(struct pt_regs *regs, struct sigcontext __user *sc) -{} -#endif - -static int -restore_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc, long long *r2_p) -{ - unsigned int err = 0; - unsigned long long current_sr, new_sr; -#define SR_MASK 0xffff8cfd - -#define COPY(x) err |= __get_user(regs->x, &sc->sc_##x) - - COPY(regs[0]); COPY(regs[1]); COPY(regs[2]); COPY(regs[3]); - COPY(regs[4]); COPY(regs[5]); COPY(regs[6]); COPY(regs[7]); - COPY(regs[8]); COPY(regs[9]); COPY(regs[10]); COPY(regs[11]); - COPY(regs[12]); COPY(regs[13]); COPY(regs[14]); COPY(regs[15]); - COPY(regs[16]); COPY(regs[17]); COPY(regs[18]); COPY(regs[19]); - COPY(regs[20]); COPY(regs[21]); COPY(regs[22]); COPY(regs[23]); - COPY(regs[24]); COPY(regs[25]); COPY(regs[26]); COPY(regs[27]); - COPY(regs[28]); COPY(regs[29]); COPY(regs[30]); COPY(regs[31]); - COPY(regs[32]); COPY(regs[33]); COPY(regs[34]); COPY(regs[35]); - COPY(regs[36]); COPY(regs[37]); COPY(regs[38]); COPY(regs[39]); - COPY(regs[40]); COPY(regs[41]); COPY(regs[42]); COPY(regs[43]); - COPY(regs[44]); COPY(regs[45]); COPY(regs[46]); COPY(regs[47]); - COPY(regs[48]); COPY(regs[49]); COPY(regs[50]); COPY(regs[51]); - COPY(regs[52]); COPY(regs[53]); COPY(regs[54]); COPY(regs[55]); - COPY(regs[56]); COPY(regs[57]); COPY(regs[58]); COPY(regs[59]); - COPY(regs[60]); COPY(regs[61]); COPY(regs[62]); - COPY(tregs[0]); COPY(tregs[1]); COPY(tregs[2]); COPY(tregs[3]); - COPY(tregs[4]); COPY(tregs[5]); COPY(tregs[6]); COPY(tregs[7]); - - /* Prevent the signal handler manipulating SR in a way that can - crash the kernel. i.e. only allow S, Q, M, PR, SZ, FR to be - modified */ - current_sr = regs->sr; - err |= __get_user(new_sr, &sc->sc_sr); - regs->sr &= SR_MASK; - regs->sr |= (new_sr & ~SR_MASK); - - COPY(pc); - -#undef COPY - - /* Must do this last in case it sets regs->sr.fd (i.e. after rest of sr - * has been restored above.) */ - err |= restore_sigcontext_fpu(regs, sc); - - regs->syscall_nr = -1; /* disable syscall checks */ - err |= __get_user(*r2_p, &sc->sc_regs[REG_RET]); - return err; -} - -asmlinkage int sys_sigreturn(unsigned long r2, unsigned long r3, - unsigned long r4, unsigned long r5, - unsigned long r6, unsigned long r7, - struct pt_regs * regs) -{ - struct sigframe __user *frame = (struct sigframe __user *) (long) REF_REG_SP; - sigset_t set; - long long ret; - - if (!access_ok(VERIFY_READ, frame, sizeof(*frame))) - goto badframe; - - if (__get_user(set.sig[0], &frame->sc.oldmask) - || (_NSIG_WORDS > 1 - && __copy_from_user(&set.sig[1], &frame->extramask, - sizeof(frame->extramask)))) - goto badframe; - - sigdelsetmask(&set, ~_BLOCKABLE); - - spin_lock_irq(¤t->sighand->siglock); - current->blocked = set; - recalc_sigpending(); - spin_unlock_irq(¤t->sighand->siglock); - - if (restore_sigcontext(regs, &frame->sc, &ret)) - goto badframe; - regs->pc -= 4; - - return (int) ret; - -badframe: - force_sig(SIGSEGV, current); - return 0; -} - -asmlinkage int sys_rt_sigreturn(unsigned long r2, unsigned long r3, - unsigned long r4, unsigned long r5, - unsigned long r6, unsigned long r7, - struct pt_regs * regs) -{ - struct rt_sigframe __user *frame = (struct rt_sigframe __user *) (long) REF_REG_SP; - sigset_t set; - stack_t __user st; - long long ret; - - if (!access_ok(VERIFY_READ, frame, sizeof(*frame))) - goto badframe; - - if (__copy_from_user(&set, &frame->uc.uc_sigmask, sizeof(set))) - goto badframe; - - sigdelsetmask(&set, ~_BLOCKABLE); - spin_lock_irq(¤t->sighand->siglock); - current->blocked = set; - recalc_sigpending(); - spin_unlock_irq(¤t->sighand->siglock); - - if (restore_sigcontext(regs, &frame->uc.uc_mcontext, &ret)) - goto badframe; - regs->pc -= 4; - - if (__copy_from_user(&st, &frame->uc.uc_stack, sizeof(st))) - goto badframe; - /* It is more difficult to avoid calling this function than to - call it and ignore errors. */ - do_sigaltstack(&st, NULL, REF_REG_SP); - - return (int) ret; - -badframe: - force_sig(SIGSEGV, current); - return 0; -} - -/* - * Set up a signal frame. - */ - -static int -setup_sigcontext(struct sigcontext __user *sc, struct pt_regs *regs, - unsigned long mask) -{ - int err = 0; - - /* Do this first, otherwise is this sets sr->fd, that value isn't preserved. */ - err |= setup_sigcontext_fpu(regs, sc); - -#define COPY(x) err |= __put_user(regs->x, &sc->sc_##x) - - COPY(regs[0]); COPY(regs[1]); COPY(regs[2]); COPY(regs[3]); - COPY(regs[4]); COPY(regs[5]); COPY(regs[6]); COPY(regs[7]); - COPY(regs[8]); COPY(regs[9]); COPY(regs[10]); COPY(regs[11]); - COPY(regs[12]); COPY(regs[13]); COPY(regs[14]); COPY(regs[15]); - COPY(regs[16]); COPY(regs[17]); COPY(regs[18]); COPY(regs[19]); - COPY(regs[20]); COPY(regs[21]); COPY(regs[22]); COPY(regs[23]); - COPY(regs[24]); COPY(regs[25]); COPY(regs[26]); COPY(regs[27]); - COPY(regs[28]); COPY(regs[29]); COPY(regs[30]); COPY(regs[31]); - COPY(regs[32]); COPY(regs[33]); COPY(regs[34]); COPY(regs[35]); - COPY(regs[36]); COPY(regs[37]); COPY(regs[38]); COPY(regs[39]); - COPY(regs[40]); COPY(regs[41]); COPY(regs[42]); COPY(regs[43]); - COPY(regs[44]); COPY(regs[45]); COPY(regs[46]); COPY(regs[47]); - COPY(regs[48]); COPY(regs[49]); COPY(regs[50]); COPY(regs[51]); - COPY(regs[52]); COPY(regs[53]); COPY(regs[54]); COPY(regs[55]); - COPY(regs[56]); COPY(regs[57]); COPY(regs[58]); COPY(regs[59]); - COPY(regs[60]); COPY(regs[61]); COPY(regs[62]); - COPY(tregs[0]); COPY(tregs[1]); COPY(tregs[2]); COPY(tregs[3]); - COPY(tregs[4]); COPY(tregs[5]); COPY(tregs[6]); COPY(tregs[7]); - COPY(sr); COPY(pc); - -#undef COPY - - err |= __put_user(mask, &sc->oldmask); - - return err; -} - -/* - * Determine which stack to use.. - */ -static inline void __user * -get_sigframe(struct k_sigaction *ka, unsigned long sp, size_t frame_size) -{ - if ((ka->sa.sa_flags & SA_ONSTACK) != 0 && ! sas_ss_flags(sp)) - sp = current->sas_ss_sp + current->sas_ss_size; - - return (void __user *)((sp - frame_size) & -8ul); -} - -void sa_default_restorer(void); /* See comments below */ -void sa_default_rt_restorer(void); /* See comments below */ - -static void setup_frame(int sig, struct k_sigaction *ka, - sigset_t *set, struct pt_regs *regs) -{ - struct sigframe __user *frame; - int err = 0; - int signal; - - frame = get_sigframe(ka, regs->regs[REG_SP], sizeof(*frame)); - - if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame))) - goto give_sigsegv; - - signal = current_thread_info()->exec_domain - && current_thread_info()->exec_domain->signal_invmap - && sig < 32 - ? current_thread_info()->exec_domain->signal_invmap[sig] - : sig; - - err |= setup_sigcontext(&frame->sc, regs, set->sig[0]); - - /* Give up earlier as i386, in case */ - if (err) - goto give_sigsegv; - - if (_NSIG_WORDS > 1) { - err |= __copy_to_user(frame->extramask, &set->sig[1], - sizeof(frame->extramask)); } - - /* Give up earlier as i386, in case */ - if (err) - goto give_sigsegv; - - /* Set up to return from userspace. If provided, use a stub - already in userspace. */ - if (ka->sa.sa_flags & SA_RESTORER) { - DEREF_REG_PR = (unsigned long) ka->sa.sa_restorer | 0x1; - - /* - * On SH5 all edited pointers are subject to NEFF - */ - DEREF_REG_PR = (DEREF_REG_PR & NEFF_SIGN) ? - (DEREF_REG_PR | NEFF_MASK) : DEREF_REG_PR; - } else { - /* - * Different approach on SH5. - * . Endianness independent asm code gets placed in entry.S . - * This is limited to four ASM instructions corresponding - * to two long longs in size. - * . err checking is done on the else branch only - * . flush_icache_range() is called upon __put_user() only - * . all edited pointers are subject to NEFF - * . being code, linker turns ShMedia bit on, always - * dereference index -1. - */ - DEREF_REG_PR = (unsigned long) frame->retcode | 0x01; - DEREF_REG_PR = (DEREF_REG_PR & NEFF_SIGN) ? - (DEREF_REG_PR | NEFF_MASK) : DEREF_REG_PR; - - if (__copy_to_user(frame->retcode, - (unsigned long long)sa_default_restorer & (~1), 16) != 0) - goto give_sigsegv; - - /* Cohere the trampoline with the I-cache. */ - flush_cache_sigtramp(DEREF_REG_PR-1, DEREF_REG_PR-1+16); - } - - /* - * Set up registers for signal handler. - * All edited pointers are subject to NEFF. - */ - regs->regs[REG_SP] = (unsigned long) frame; - regs->regs[REG_SP] = (regs->regs[REG_SP] & NEFF_SIGN) ? - (regs->regs[REG_SP] | NEFF_MASK) : regs->regs[REG_SP]; - regs->regs[REG_ARG1] = signal; /* Arg for signal handler */ - - /* FIXME: - The glibc profiling support for SH-5 needs to be passed a sigcontext - so it can retrieve the PC. At some point during 2003 the glibc - support was changed to receive the sigcontext through the 2nd - argument, but there are still versions of libc.so in use that use - the 3rd argument. Until libc.so is stabilised, pass the sigcontext - through both 2nd and 3rd arguments. - */ - - regs->regs[REG_ARG2] = (unsigned long long)(unsigned long)(signed long)&frame->sc; - regs->regs[REG_ARG3] = (unsigned long long)(unsigned long)(signed long)&frame->sc; - - regs->pc = (unsigned long) ka->sa.sa_handler; - regs->pc = (regs->pc & NEFF_SIGN) ? (regs->pc | NEFF_MASK) : regs->pc; - - set_fs(USER_DS); - -#if DEBUG_SIG - /* Broken %016Lx */ - printk("SIG deliver (#%d,%s:%d): sp=%p pc=%08Lx%08Lx link=%08Lx%08Lx\n", - signal, - current->comm, current->pid, frame, - regs->pc >> 32, regs->pc & 0xffffffff, - DEREF_REG_PR >> 32, DEREF_REG_PR & 0xffffffff); -#endif - - return; - -give_sigsegv: - force_sigsegv(sig, current); -} - -static void setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info, - sigset_t *set, struct pt_regs *regs) -{ - struct rt_sigframe __user *frame; - int err = 0; - int signal; - - frame = get_sigframe(ka, regs->regs[REG_SP], sizeof(*frame)); - - if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame))) - goto give_sigsegv; - - signal = current_thread_info()->exec_domain - && current_thread_info()->exec_domain->signal_invmap - && sig < 32 - ? current_thread_info()->exec_domain->signal_invmap[sig] - : sig; - - err |= __put_user(&frame->info, &frame->pinfo); - err |= __put_user(&frame->uc, &frame->puc); - err |= copy_siginfo_to_user(&frame->info, info); - - /* Give up earlier as i386, in case */ - if (err) - goto give_sigsegv; - - /* Create the ucontext. */ - err |= __put_user(0, &frame->uc.uc_flags); - err |= __put_user(0, &frame->uc.uc_link); - err |= __put_user((void *)current->sas_ss_sp, - &frame->uc.uc_stack.ss_sp); - err |= __put_user(sas_ss_flags(regs->regs[REG_SP]), - &frame->uc.uc_stack.ss_flags); - err |= __put_user(current->sas_ss_size, &frame->uc.uc_stack.ss_size); - err |= setup_sigcontext(&frame->uc.uc_mcontext, - regs, set->sig[0]); - err |= __copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set)); - - /* Give up earlier as i386, in case */ - if (err) - goto give_sigsegv; - - /* Set up to return from userspace. If provided, use a stub - already in userspace. */ - if (ka->sa.sa_flags & SA_RESTORER) { - DEREF_REG_PR = (unsigned long) ka->sa.sa_restorer | 0x1; - - /* - * On SH5 all edited pointers are subject to NEFF - */ - DEREF_REG_PR = (DEREF_REG_PR & NEFF_SIGN) ? - (DEREF_REG_PR | NEFF_MASK) : DEREF_REG_PR; - } else { - /* - * Different approach on SH5. - * . Endianness independent asm code gets placed in entry.S . - * This is limited to four ASM instructions corresponding - * to two long longs in size. - * . err checking is done on the else branch only - * . flush_icache_range() is called upon __put_user() only - * . all edited pointers are subject to NEFF - * . being code, linker turns ShMedia bit on, always - * dereference index -1. - */ - - DEREF_REG_PR = (unsigned long) frame->retcode | 0x01; - DEREF_REG_PR = (DEREF_REG_PR & NEFF_SIGN) ? - (DEREF_REG_PR | NEFF_MASK) : DEREF_REG_PR; - - if (__copy_to_user(frame->retcode, - (unsigned long long)sa_default_rt_restorer & (~1), 16) != 0) - goto give_sigsegv; - - flush_icache_range(DEREF_REG_PR-1, DEREF_REG_PR-1+15); - } - - /* - * Set up registers for signal handler. - * All edited pointers are subject to NEFF. - */ - regs->regs[REG_SP] = (unsigned long) frame; - regs->regs[REG_SP] = (regs->regs[REG_SP] & NEFF_SIGN) ? - (regs->regs[REG_SP] | NEFF_MASK) : regs->regs[REG_SP]; - regs->regs[REG_ARG1] = signal; /* Arg for signal handler */ - regs->regs[REG_ARG2] = (unsigned long long)(unsigned long)(signed long)&frame->info; - regs->regs[REG_ARG3] = (unsigned long long)(unsigned long)(signed long)&frame->uc.uc_mcontext; - regs->pc = (unsigned long) ka->sa.sa_handler; - regs->pc = (regs->pc & NEFF_SIGN) ? (regs->pc | NEFF_MASK) : regs->pc; - - set_fs(USER_DS); - -#if DEBUG_SIG - /* Broken %016Lx */ - printk("SIG deliver (#%d,%s:%d): sp=%p pc=%08Lx%08Lx link=%08Lx%08Lx\n", - signal, - current->comm, current->pid, frame, - regs->pc >> 32, regs->pc & 0xffffffff, - DEREF_REG_PR >> 32, DEREF_REG_PR & 0xffffffff); -#endif - - return; - -give_sigsegv: - force_sigsegv(sig, current); -} - -/* - * OK, we're invoking a handler - */ - -static void -handle_signal(unsigned long sig, siginfo_t *info, struct k_sigaction *ka, - sigset_t *oldset, struct pt_regs * regs) -{ - /* Are we from a system call? */ - if (regs->syscall_nr >= 0) { - /* If so, check system call restarting.. */ - switch (regs->regs[REG_RET]) { - case -ERESTART_RESTARTBLOCK: - case -ERESTARTNOHAND: - regs->regs[REG_RET] = -EINTR; - break; - - case -ERESTARTSYS: - if (!(ka->sa.sa_flags & SA_RESTART)) { - regs->regs[REG_RET] = -EINTR; - break; - } - /* fallthrough */ - case -ERESTARTNOINTR: - /* Decode syscall # */ - regs->regs[REG_RET] = regs->syscall_nr; - regs->pc -= 4; - } - } - - /* Set up the stack frame */ - if (ka->sa.sa_flags & SA_SIGINFO) - setup_rt_frame(sig, ka, info, oldset, regs); - else - setup_frame(sig, ka, oldset, regs); - - spin_lock_irq(¤t->sighand->siglock); - sigorsets(¤t->blocked,¤t->blocked,&ka->sa.sa_mask); - if (!(ka->sa.sa_flags & SA_NODEFER)) - sigaddset(¤t->blocked,sig); - recalc_sigpending(); - spin_unlock_irq(¤t->sighand->siglock); -} - -/* - * Note that 'init' is a special process: it doesn't get signals it doesn't - * want to handle. Thus you cannot kill init even with a SIGKILL even by - * mistake. - * - * Note that we go through the signals twice: once to check the signals that - * the kernel can handle, and then we build all the user-level signal handling - * stack-frames in one go after that. - */ -int do_signal(struct pt_regs *regs, sigset_t *oldset) -{ - siginfo_t info; - int signr; - struct k_sigaction ka; - - /* - * We want the common case to go fast, which - * is why we may in certain cases get here from - * kernel mode. Just return without doing anything - * if so. - */ - if (!user_mode(regs)) - return 1; - - if (try_to_freeze()) - goto no_signal; - - if (test_thread_flag(TIF_RESTORE_SIGMASK)) - oldset = ¤t->saved_sigmask; - else if (!oldset) - oldset = ¤t->blocked; - - signr = get_signal_to_deliver(&info, &ka, regs, 0); - - if (signr > 0) { - /* Whee! Actually deliver the signal. */ - handle_signal(signr, &info, &ka, oldset, regs); - - /* - * If a signal was successfully delivered, the saved sigmask - * is in its frame, and we can clear the TIF_RESTORE_SIGMASK - * flag. - */ - if (test_thread_flag(TIF_RESTORE_SIGMASK)) - clear_thread_flag(TIF_RESTORE_SIGMASK); - - return 1; - } - -no_signal: - /* Did we come from a system call? */ - if (regs->syscall_nr >= 0) { - /* Restart the system call - no handlers present */ - switch (regs->regs[REG_RET]) { - case -ERESTARTNOHAND: - case -ERESTARTSYS: - case -ERESTARTNOINTR: - /* Decode Syscall # */ - regs->regs[REG_RET] = regs->syscall_nr; - regs->pc -= 4; - break; - - case -ERESTART_RESTARTBLOCK: - regs->regs[REG_RET] = __NR_restart_syscall; - regs->pc -= 4; - break; - } - } - - /* No signal to deliver -- put the saved sigmask back */ - if (test_thread_flag(TIF_RESTORE_SIGMASK)) { - clear_thread_flag(TIF_RESTORE_SIGMASK); - sigprocmask(SIG_SETMASK, ¤t->saved_sigmask, NULL); - } - - return 0; -} |