774 lines
22 KiB
C
774 lines
22 KiB
C
/*
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* arch/ppc/kernel/signal.c
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*
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* PowerPC version
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* Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org)
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*
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* Derived from "arch/i386/kernel/signal.c"
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* Copyright (C) 1991, 1992 Linus Torvalds
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* 1997-11-28 Modified for POSIX.1b signals by Richard Henderson
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*
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* This program is free software; you can redistribute it and/or
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* modify it under the terms of the GNU General Public License
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* as published by the Free Software Foundation; either version
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* 2 of the License, or (at your option) any later version.
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*/
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#include <linux/sched.h>
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#include <linux/mm.h>
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#include <linux/smp.h>
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#include <linux/smp_lock.h>
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#include <linux/kernel.h>
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#include <linux/signal.h>
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#include <linux/errno.h>
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#include <linux/wait.h>
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#include <linux/ptrace.h>
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#include <linux/unistd.h>
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#include <linux/stddef.h>
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#include <linux/elf.h>
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#include <linux/tty.h>
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#include <linux/binfmts.h>
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#include <linux/suspend.h>
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#include <asm/ucontext.h>
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#include <asm/uaccess.h>
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#include <asm/pgtable.h>
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#include <asm/cacheflush.h>
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#undef DEBUG_SIG
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#define _BLOCKABLE (~(sigmask(SIGKILL) | sigmask(SIGSTOP)))
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extern void sigreturn_exit(struct pt_regs *);
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#define GP_REGS_SIZE min(sizeof(elf_gregset_t), sizeof(struct pt_regs))
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int do_signal(sigset_t *oldset, struct pt_regs *regs);
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/*
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* Atomically swap in the new signal mask, and wait for a signal.
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*/
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int
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sys_sigsuspend(old_sigset_t mask, int p2, int p3, int p4, int p6, int p7,
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struct pt_regs *regs)
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{
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sigset_t saveset;
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mask &= _BLOCKABLE;
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spin_lock_irq(¤t->sighand->siglock);
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saveset = current->blocked;
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siginitset(¤t->blocked, mask);
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recalc_sigpending();
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spin_unlock_irq(¤t->sighand->siglock);
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regs->result = -EINTR;
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regs->gpr[3] = EINTR;
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regs->ccr |= 0x10000000;
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while (1) {
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current->state = TASK_INTERRUPTIBLE;
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schedule();
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if (do_signal(&saveset, regs))
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sigreturn_exit(regs);
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}
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}
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int
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sys_rt_sigsuspend(sigset_t __user *unewset, size_t sigsetsize, int p3, int p4,
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int p6, int p7, struct pt_regs *regs)
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{
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sigset_t saveset, newset;
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/* XXX: Don't preclude handling different sized sigset_t's. */
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if (sigsetsize != sizeof(sigset_t))
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return -EINVAL;
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if (copy_from_user(&newset, unewset, sizeof(newset)))
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return -EFAULT;
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sigdelsetmask(&newset, ~_BLOCKABLE);
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spin_lock_irq(¤t->sighand->siglock);
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saveset = current->blocked;
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current->blocked = newset;
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recalc_sigpending();
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spin_unlock_irq(¤t->sighand->siglock);
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regs->result = -EINTR;
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regs->gpr[3] = EINTR;
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regs->ccr |= 0x10000000;
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while (1) {
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current->state = TASK_INTERRUPTIBLE;
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schedule();
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if (do_signal(&saveset, regs))
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sigreturn_exit(regs);
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}
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}
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int
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sys_sigaltstack(const stack_t __user *uss, stack_t __user *uoss, int r5,
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int r6, int r7, int r8, struct pt_regs *regs)
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{
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return do_sigaltstack(uss, uoss, regs->gpr[1]);
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}
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int
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sys_sigaction(int sig, const struct old_sigaction __user *act,
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struct old_sigaction __user *oact)
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{
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struct k_sigaction new_ka, old_ka;
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int ret;
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if (act) {
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old_sigset_t mask;
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if (!access_ok(VERIFY_READ, act, sizeof(*act)) ||
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__get_user(new_ka.sa.sa_handler, &act->sa_handler) ||
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__get_user(new_ka.sa.sa_restorer, &act->sa_restorer))
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return -EFAULT;
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__get_user(new_ka.sa.sa_flags, &act->sa_flags);
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__get_user(mask, &act->sa_mask);
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siginitset(&new_ka.sa.sa_mask, mask);
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}
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ret = do_sigaction(sig, (act? &new_ka: NULL), (oact? &old_ka: NULL));
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if (!ret && oact) {
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if (!access_ok(VERIFY_WRITE, oact, sizeof(*oact)) ||
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__put_user(old_ka.sa.sa_handler, &oact->sa_handler) ||
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__put_user(old_ka.sa.sa_restorer, &oact->sa_restorer))
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return -EFAULT;
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__put_user(old_ka.sa.sa_flags, &oact->sa_flags);
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__put_user(old_ka.sa.sa_mask.sig[0], &oact->sa_mask);
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}
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return ret;
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}
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/*
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* When we have signals to deliver, we set up on the
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* user stack, going down from the original stack pointer:
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* a sigregs struct
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* a sigcontext struct
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* a gap of __SIGNAL_FRAMESIZE bytes
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*
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* Each of these things must be a multiple of 16 bytes in size.
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*
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*/
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struct sigregs {
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struct mcontext mctx; /* all the register values */
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/* Programs using the rs6000/xcoff abi can save up to 19 gp regs
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and 18 fp regs below sp before decrementing it. */
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int abigap[56];
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};
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/* We use the mc_pad field for the signal return trampoline. */
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#define tramp mc_pad
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/*
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* When we have rt signals to deliver, we set up on the
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* user stack, going down from the original stack pointer:
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* one rt_sigframe struct (siginfo + ucontext + ABI gap)
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* a gap of __SIGNAL_FRAMESIZE+16 bytes
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* (the +16 is to get the siginfo and ucontext in the same
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* positions as in older kernels).
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*
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* Each of these things must be a multiple of 16 bytes in size.
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*
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*/
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struct rt_sigframe
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{
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struct siginfo info;
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struct ucontext uc;
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/* Programs using the rs6000/xcoff abi can save up to 19 gp regs
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and 18 fp regs below sp before decrementing it. */
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int abigap[56];
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};
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/*
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* Save the current user registers on the user stack.
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* We only save the altivec/spe registers if the process has used
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* altivec/spe instructions at some point.
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*/
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static int
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save_user_regs(struct pt_regs *regs, struct mcontext __user *frame, int sigret)
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{
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/* save general and floating-point registers */
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CHECK_FULL_REGS(regs);
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preempt_disable();
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if (regs->msr & MSR_FP)
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giveup_fpu(current);
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#ifdef CONFIG_ALTIVEC
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if (current->thread.used_vr && (regs->msr & MSR_VEC))
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giveup_altivec(current);
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#endif /* CONFIG_ALTIVEC */
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#ifdef CONFIG_SPE
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if (current->thread.used_spe && (regs->msr & MSR_SPE))
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giveup_spe(current);
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#endif /* CONFIG_ALTIVEC */
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preempt_enable();
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if (__copy_to_user(&frame->mc_gregs, regs, GP_REGS_SIZE)
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|| __copy_to_user(&frame->mc_fregs, current->thread.fpr,
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ELF_NFPREG * sizeof(double)))
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return 1;
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current->thread.fpscr = 0; /* turn off all fp exceptions */
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#ifdef CONFIG_ALTIVEC
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/* save altivec registers */
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if (current->thread.used_vr) {
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if (__copy_to_user(&frame->mc_vregs, current->thread.vr,
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ELF_NVRREG * sizeof(vector128)))
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return 1;
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/* set MSR_VEC in the saved MSR value to indicate that
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frame->mc_vregs contains valid data */
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if (__put_user(regs->msr | MSR_VEC, &frame->mc_gregs[PT_MSR]))
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return 1;
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}
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/* else assert((regs->msr & MSR_VEC) == 0) */
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/* We always copy to/from vrsave, it's 0 if we don't have or don't
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* use altivec. Since VSCR only contains 32 bits saved in the least
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* significant bits of a vector, we "cheat" and stuff VRSAVE in the
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* most significant bits of that same vector. --BenH
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*/
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if (__put_user(current->thread.vrsave, (u32 __user *)&frame->mc_vregs[32]))
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return 1;
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#endif /* CONFIG_ALTIVEC */
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#ifdef CONFIG_SPE
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/* save spe registers */
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if (current->thread.used_spe) {
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if (__copy_to_user(&frame->mc_vregs, current->thread.evr,
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ELF_NEVRREG * sizeof(u32)))
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return 1;
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/* set MSR_SPE in the saved MSR value to indicate that
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frame->mc_vregs contains valid data */
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if (__put_user(regs->msr | MSR_SPE, &frame->mc_gregs[PT_MSR]))
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return 1;
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}
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/* else assert((regs->msr & MSR_SPE) == 0) */
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/* We always copy to/from spefscr */
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if (__put_user(current->thread.spefscr, (u32 *)&frame->mc_vregs + ELF_NEVRREG))
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return 1;
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#endif /* CONFIG_SPE */
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if (sigret) {
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/* Set up the sigreturn trampoline: li r0,sigret; sc */
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if (__put_user(0x38000000UL + sigret, &frame->tramp[0])
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|| __put_user(0x44000002UL, &frame->tramp[1]))
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return 1;
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flush_icache_range((unsigned long) &frame->tramp[0],
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(unsigned long) &frame->tramp[2]);
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}
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return 0;
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}
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/*
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* Restore the current user register values from the user stack,
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* (except for MSR).
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*/
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static int
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restore_user_regs(struct pt_regs *regs, struct mcontext __user *sr, int sig)
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{
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unsigned long save_r2 = 0;
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#if defined(CONFIG_ALTIVEC) || defined(CONFIG_SPE)
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unsigned long msr;
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#endif
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/* backup/restore the TLS as we don't want it to be modified */
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if (!sig)
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save_r2 = regs->gpr[2];
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/* copy up to but not including MSR */
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if (__copy_from_user(regs, &sr->mc_gregs, PT_MSR * sizeof(elf_greg_t)))
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return 1;
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/* copy from orig_r3 (the word after the MSR) up to the end */
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if (__copy_from_user(®s->orig_gpr3, &sr->mc_gregs[PT_ORIG_R3],
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GP_REGS_SIZE - PT_ORIG_R3 * sizeof(elf_greg_t)))
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return 1;
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if (!sig)
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regs->gpr[2] = save_r2;
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/* force the process to reload the FP registers from
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current->thread when it next does FP instructions */
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regs->msr &= ~(MSR_FP | MSR_FE0 | MSR_FE1);
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if (__copy_from_user(current->thread.fpr, &sr->mc_fregs,
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sizeof(sr->mc_fregs)))
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return 1;
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#ifdef CONFIG_ALTIVEC
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/* force the process to reload the altivec registers from
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current->thread when it next does altivec instructions */
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regs->msr &= ~MSR_VEC;
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if (!__get_user(msr, &sr->mc_gregs[PT_MSR]) && (msr & MSR_VEC) != 0) {
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/* restore altivec registers from the stack */
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if (__copy_from_user(current->thread.vr, &sr->mc_vregs,
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sizeof(sr->mc_vregs)))
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return 1;
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} else if (current->thread.used_vr)
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memset(¤t->thread.vr, 0, ELF_NVRREG * sizeof(vector128));
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/* Always get VRSAVE back */
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if (__get_user(current->thread.vrsave, (u32 __user *)&sr->mc_vregs[32]))
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return 1;
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#endif /* CONFIG_ALTIVEC */
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#ifdef CONFIG_SPE
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/* force the process to reload the spe registers from
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current->thread when it next does spe instructions */
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regs->msr &= ~MSR_SPE;
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if (!__get_user(msr, &sr->mc_gregs[PT_MSR]) && (msr & MSR_SPE) != 0) {
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/* restore spe registers from the stack */
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if (__copy_from_user(current->thread.evr, &sr->mc_vregs,
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ELF_NEVRREG * sizeof(u32)))
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return 1;
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} else if (current->thread.used_spe)
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memset(¤t->thread.evr, 0, ELF_NEVRREG * sizeof(u32));
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/* Always get SPEFSCR back */
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if (__get_user(current->thread.spefscr, (u32 *)&sr->mc_vregs + ELF_NEVRREG))
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return 1;
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#endif /* CONFIG_SPE */
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#ifndef CONFIG_SMP
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preempt_disable();
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if (last_task_used_math == current)
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last_task_used_math = NULL;
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if (last_task_used_altivec == current)
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last_task_used_altivec = NULL;
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if (last_task_used_spe == current)
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last_task_used_spe = NULL;
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preempt_enable();
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#endif
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return 0;
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}
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/*
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* Restore the user process's signal mask
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*/
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static void
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restore_sigmask(sigset_t *set)
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{
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sigdelsetmask(set, ~_BLOCKABLE);
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spin_lock_irq(¤t->sighand->siglock);
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current->blocked = *set;
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recalc_sigpending();
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spin_unlock_irq(¤t->sighand->siglock);
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}
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/*
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* Set up a signal frame for a "real-time" signal handler
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* (one which gets siginfo).
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*/
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static void
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handle_rt_signal(unsigned long sig, struct k_sigaction *ka,
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siginfo_t *info, sigset_t *oldset, struct pt_regs * regs,
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unsigned long newsp)
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{
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struct rt_sigframe __user *rt_sf;
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struct mcontext __user *frame;
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unsigned long origsp = newsp;
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/* Set up Signal Frame */
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/* Put a Real Time Context onto stack */
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newsp -= sizeof(*rt_sf);
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rt_sf = (struct rt_sigframe __user *) newsp;
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/* create a stack frame for the caller of the handler */
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newsp -= __SIGNAL_FRAMESIZE + 16;
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if (!access_ok(VERIFY_WRITE, (void __user *) newsp, origsp - newsp))
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goto badframe;
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/* Put the siginfo & fill in most of the ucontext */
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if (copy_siginfo_to_user(&rt_sf->info, info)
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|| __put_user(0, &rt_sf->uc.uc_flags)
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|| __put_user(0, &rt_sf->uc.uc_link)
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|| __put_user(current->sas_ss_sp, &rt_sf->uc.uc_stack.ss_sp)
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|| __put_user(sas_ss_flags(regs->gpr[1]),
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&rt_sf->uc.uc_stack.ss_flags)
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|| __put_user(current->sas_ss_size, &rt_sf->uc.uc_stack.ss_size)
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|| __put_user(&rt_sf->uc.uc_mcontext, &rt_sf->uc.uc_regs)
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|| __copy_to_user(&rt_sf->uc.uc_sigmask, oldset, sizeof(*oldset)))
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goto badframe;
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/* Save user registers on the stack */
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frame = &rt_sf->uc.uc_mcontext;
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if (save_user_regs(regs, frame, __NR_rt_sigreturn))
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goto badframe;
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if (put_user(regs->gpr[1], (unsigned long __user *)newsp))
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goto badframe;
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regs->gpr[1] = newsp;
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regs->gpr[3] = sig;
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regs->gpr[4] = (unsigned long) &rt_sf->info;
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regs->gpr[5] = (unsigned long) &rt_sf->uc;
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regs->gpr[6] = (unsigned long) rt_sf;
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regs->nip = (unsigned long) ka->sa.sa_handler;
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regs->link = (unsigned long) frame->tramp;
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regs->trap = 0;
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return;
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badframe:
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#ifdef DEBUG_SIG
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printk("badframe in handle_rt_signal, regs=%p frame=%p newsp=%lx\n",
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regs, frame, newsp);
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#endif
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force_sigsegv(sig, current);
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}
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static int do_setcontext(struct ucontext __user *ucp, struct pt_regs *regs, int sig)
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{
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sigset_t set;
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struct mcontext __user *mcp;
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if (__copy_from_user(&set, &ucp->uc_sigmask, sizeof(set))
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|| __get_user(mcp, &ucp->uc_regs))
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return -EFAULT;
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restore_sigmask(&set);
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if (restore_user_regs(regs, mcp, sig))
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return -EFAULT;
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return 0;
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}
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int sys_swapcontext(struct ucontext __user *old_ctx,
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struct ucontext __user *new_ctx,
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int ctx_size, int r6, int r7, int r8, struct pt_regs *regs)
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{
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unsigned char tmp;
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/* Context size is for future use. Right now, we only make sure
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* we are passed something we understand
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*/
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if (ctx_size < sizeof(struct ucontext))
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return -EINVAL;
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if (old_ctx != NULL) {
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if (!access_ok(VERIFY_WRITE, old_ctx, sizeof(*old_ctx))
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|| save_user_regs(regs, &old_ctx->uc_mcontext, 0)
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|| __copy_to_user(&old_ctx->uc_sigmask,
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¤t->blocked, sizeof(sigset_t))
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|| __put_user(&old_ctx->uc_mcontext, &old_ctx->uc_regs))
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return -EFAULT;
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}
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if (new_ctx == NULL)
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return 0;
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if (!access_ok(VERIFY_READ, new_ctx, sizeof(*new_ctx))
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|| __get_user(tmp, (u8 __user *) new_ctx)
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|| __get_user(tmp, (u8 __user *) (new_ctx + 1) - 1))
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return -EFAULT;
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/*
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* If we get a fault copying the context into the kernel's
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* image of the user's registers, we can't just return -EFAULT
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* because the user's registers will be corrupted. For instance
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* the NIP value may have been updated but not some of the
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* other registers. Given that we have done the access_ok
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* and successfully read the first and last bytes of the region
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* above, this should only happen in an out-of-memory situation
|
|
* or if another thread unmaps the region containing the context.
|
|
* We kill the task with a SIGSEGV in this situation.
|
|
*/
|
|
if (do_setcontext(new_ctx, regs, 0))
|
|
do_exit(SIGSEGV);
|
|
sigreturn_exit(regs);
|
|
/* doesn't actually return back to here */
|
|
return 0;
|
|
}
|
|
|
|
int sys_rt_sigreturn(int r3, int r4, int r5, int r6, int r7, int r8,
|
|
struct pt_regs *regs)
|
|
{
|
|
struct rt_sigframe __user *rt_sf;
|
|
|
|
/* Always make any pending restarted system calls return -EINTR */
|
|
current_thread_info()->restart_block.fn = do_no_restart_syscall;
|
|
|
|
rt_sf = (struct rt_sigframe __user *)
|
|
(regs->gpr[1] + __SIGNAL_FRAMESIZE + 16);
|
|
if (!access_ok(VERIFY_READ, rt_sf, sizeof(struct rt_sigframe)))
|
|
goto bad;
|
|
if (do_setcontext(&rt_sf->uc, regs, 1))
|
|
goto bad;
|
|
|
|
/*
|
|
* It's not clear whether or why it is desirable to save the
|
|
* sigaltstack setting on signal delivery and restore it on
|
|
* signal return. But other architectures do this and we have
|
|
* always done it up until now so it is probably better not to
|
|
* change it. -- paulus
|
|
*/
|
|
do_sigaltstack(&rt_sf->uc.uc_stack, NULL, regs->gpr[1]);
|
|
|
|
sigreturn_exit(regs); /* doesn't return here */
|
|
return 0;
|
|
|
|
bad:
|
|
force_sig(SIGSEGV, current);
|
|
return 0;
|
|
}
|
|
|
|
int sys_debug_setcontext(struct ucontext __user *ctx,
|
|
int ndbg, struct sig_dbg_op *dbg,
|
|
int r6, int r7, int r8,
|
|
struct pt_regs *regs)
|
|
{
|
|
struct sig_dbg_op op;
|
|
int i;
|
|
unsigned long new_msr = regs->msr;
|
|
#if defined(CONFIG_4xx) || defined(CONFIG_BOOKE)
|
|
unsigned long new_dbcr0 = current->thread.dbcr0;
|
|
#endif
|
|
|
|
for (i=0; i<ndbg; i++) {
|
|
if (__copy_from_user(&op, dbg, sizeof(op)))
|
|
return -EFAULT;
|
|
switch (op.dbg_type) {
|
|
case SIG_DBG_SINGLE_STEPPING:
|
|
#if defined(CONFIG_4xx) || defined(CONFIG_BOOKE)
|
|
if (op.dbg_value) {
|
|
new_msr |= MSR_DE;
|
|
new_dbcr0 |= (DBCR0_IDM | DBCR0_IC);
|
|
} else {
|
|
new_msr &= ~MSR_DE;
|
|
new_dbcr0 &= ~(DBCR0_IDM | DBCR0_IC);
|
|
}
|
|
#else
|
|
if (op.dbg_value)
|
|
new_msr |= MSR_SE;
|
|
else
|
|
new_msr &= ~MSR_SE;
|
|
#endif
|
|
break;
|
|
case SIG_DBG_BRANCH_TRACING:
|
|
#if defined(CONFIG_4xx) || defined(CONFIG_BOOKE)
|
|
return -EINVAL;
|
|
#else
|
|
if (op.dbg_value)
|
|
new_msr |= MSR_BE;
|
|
else
|
|
new_msr &= ~MSR_BE;
|
|
#endif
|
|
break;
|
|
|
|
default:
|
|
return -EINVAL;
|
|
}
|
|
}
|
|
|
|
/* We wait until here to actually install the values in the
|
|
registers so if we fail in the above loop, it will not
|
|
affect the contents of these registers. After this point,
|
|
failure is a problem, anyway, and it's very unlikely unless
|
|
the user is really doing something wrong. */
|
|
regs->msr = new_msr;
|
|
#if defined(CONFIG_4xx) || defined(CONFIG_BOOKE)
|
|
current->thread.dbcr0 = new_dbcr0;
|
|
#endif
|
|
|
|
/*
|
|
* If we get a fault copying the context into the kernel's
|
|
* image of the user's registers, we can't just return -EFAULT
|
|
* because the user's registers will be corrupted. For instance
|
|
* the NIP value may have been updated but not some of the
|
|
* other registers. Given that we have done the access_ok
|
|
* and successfully read the first and last bytes of the region
|
|
* above, this should only happen in an out-of-memory situation
|
|
* or if another thread unmaps the region containing the context.
|
|
* We kill the task with a SIGSEGV in this situation.
|
|
*/
|
|
if (do_setcontext(ctx, regs, 1)) {
|
|
force_sig(SIGSEGV, current);
|
|
goto out;
|
|
}
|
|
|
|
/*
|
|
* It's not clear whether or why it is desirable to save the
|
|
* sigaltstack setting on signal delivery and restore it on
|
|
* signal return. But other architectures do this and we have
|
|
* always done it up until now so it is probably better not to
|
|
* change it. -- paulus
|
|
*/
|
|
do_sigaltstack(&ctx->uc_stack, NULL, regs->gpr[1]);
|
|
|
|
sigreturn_exit(regs);
|
|
/* doesn't actually return back to here */
|
|
|
|
out:
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* OK, we're invoking a handler
|
|
*/
|
|
static void
|
|
handle_signal(unsigned long sig, struct k_sigaction *ka,
|
|
siginfo_t *info, sigset_t *oldset, struct pt_regs * regs,
|
|
unsigned long newsp)
|
|
{
|
|
struct sigcontext __user *sc;
|
|
struct sigregs __user *frame;
|
|
unsigned long origsp = newsp;
|
|
|
|
/* Set up Signal Frame */
|
|
newsp -= sizeof(struct sigregs);
|
|
frame = (struct sigregs __user *) newsp;
|
|
|
|
/* Put a sigcontext on the stack */
|
|
newsp -= sizeof(*sc);
|
|
sc = (struct sigcontext __user *) newsp;
|
|
|
|
/* create a stack frame for the caller of the handler */
|
|
newsp -= __SIGNAL_FRAMESIZE;
|
|
|
|
if (!access_ok(VERIFY_WRITE, (void __user *) newsp, origsp - newsp))
|
|
goto badframe;
|
|
|
|
#if _NSIG != 64
|
|
#error "Please adjust handle_signal()"
|
|
#endif
|
|
if (__put_user((unsigned long) ka->sa.sa_handler, &sc->handler)
|
|
|| __put_user(oldset->sig[0], &sc->oldmask)
|
|
|| __put_user(oldset->sig[1], &sc->_unused[3])
|
|
|| __put_user((struct pt_regs *)frame, &sc->regs)
|
|
|| __put_user(sig, &sc->signal))
|
|
goto badframe;
|
|
|
|
if (save_user_regs(regs, &frame->mctx, __NR_sigreturn))
|
|
goto badframe;
|
|
|
|
if (put_user(regs->gpr[1], (unsigned long __user *)newsp))
|
|
goto badframe;
|
|
regs->gpr[1] = newsp;
|
|
regs->gpr[3] = sig;
|
|
regs->gpr[4] = (unsigned long) sc;
|
|
regs->nip = (unsigned long) ka->sa.sa_handler;
|
|
regs->link = (unsigned long) frame->mctx.tramp;
|
|
regs->trap = 0;
|
|
|
|
return;
|
|
|
|
badframe:
|
|
#ifdef DEBUG_SIG
|
|
printk("badframe in handle_signal, regs=%p frame=%p newsp=%lx\n",
|
|
regs, frame, newsp);
|
|
#endif
|
|
force_sigsegv(sig, current);
|
|
}
|
|
|
|
/*
|
|
* Do a signal return; undo the signal stack.
|
|
*/
|
|
int sys_sigreturn(int r3, int r4, int r5, int r6, int r7, int r8,
|
|
struct pt_regs *regs)
|
|
{
|
|
struct sigcontext __user *sc;
|
|
struct sigcontext sigctx;
|
|
struct mcontext __user *sr;
|
|
sigset_t set;
|
|
|
|
/* Always make any pending restarted system calls return -EINTR */
|
|
current_thread_info()->restart_block.fn = do_no_restart_syscall;
|
|
|
|
sc = (struct sigcontext __user *)(regs->gpr[1] + __SIGNAL_FRAMESIZE);
|
|
if (copy_from_user(&sigctx, sc, sizeof(sigctx)))
|
|
goto badframe;
|
|
|
|
set.sig[0] = sigctx.oldmask;
|
|
set.sig[1] = sigctx._unused[3];
|
|
restore_sigmask(&set);
|
|
|
|
sr = (struct mcontext __user *) sigctx.regs;
|
|
if (!access_ok(VERIFY_READ, sr, sizeof(*sr))
|
|
|| restore_user_regs(regs, sr, 1))
|
|
goto badframe;
|
|
|
|
sigreturn_exit(regs); /* doesn't return */
|
|
return 0;
|
|
|
|
badframe:
|
|
force_sig(SIGSEGV, current);
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* 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.
|
|
*/
|
|
int do_signal(sigset_t *oldset, struct pt_regs *regs)
|
|
{
|
|
siginfo_t info;
|
|
struct k_sigaction ka;
|
|
unsigned long frame, newsp;
|
|
int signr, ret;
|
|
|
|
if (current->flags & PF_FREEZE) {
|
|
refrigerator(PF_FREEZE);
|
|
signr = 0;
|
|
if (!signal_pending(current))
|
|
goto no_signal;
|
|
}
|
|
|
|
if (!oldset)
|
|
oldset = ¤t->blocked;
|
|
|
|
newsp = frame = 0;
|
|
|
|
signr = get_signal_to_deliver(&info, &ka, regs, NULL);
|
|
no_signal:
|
|
if (TRAP(regs) == 0x0C00 /* System Call! */
|
|
&& regs->ccr & 0x10000000 /* error signalled */
|
|
&& ((ret = regs->gpr[3]) == ERESTARTSYS
|
|
|| ret == ERESTARTNOHAND || ret == ERESTARTNOINTR
|
|
|| ret == ERESTART_RESTARTBLOCK)) {
|
|
|
|
if (signr > 0
|
|
&& (ret == ERESTARTNOHAND || ret == ERESTART_RESTARTBLOCK
|
|
|| (ret == ERESTARTSYS
|
|
&& !(ka.sa.sa_flags & SA_RESTART)))) {
|
|
/* make the system call return an EINTR error */
|
|
regs->result = -EINTR;
|
|
regs->gpr[3] = EINTR;
|
|
/* note that the cr0.SO bit is already set */
|
|
} else {
|
|
regs->nip -= 4; /* Back up & retry system call */
|
|
regs->result = 0;
|
|
regs->trap = 0;
|
|
if (ret == ERESTART_RESTARTBLOCK)
|
|
regs->gpr[0] = __NR_restart_syscall;
|
|
else
|
|
regs->gpr[3] = regs->orig_gpr3;
|
|
}
|
|
}
|
|
|
|
if (signr == 0)
|
|
return 0; /* no signals delivered */
|
|
|
|
if ((ka.sa.sa_flags & SA_ONSTACK) && current->sas_ss_size
|
|
&& !on_sig_stack(regs->gpr[1]))
|
|
newsp = current->sas_ss_sp + current->sas_ss_size;
|
|
else
|
|
newsp = regs->gpr[1];
|
|
newsp &= ~0xfUL;
|
|
|
|
/* Whee! Actually deliver the signal. */
|
|
if (ka.sa.sa_flags & SA_SIGINFO)
|
|
handle_rt_signal(signr, &ka, &info, oldset, regs, newsp);
|
|
else
|
|
handle_signal(signr, &ka, &info, oldset, regs, newsp);
|
|
|
|
if (!(ka.sa.sa_flags & SA_NODEFER)) {
|
|
spin_lock_irq(¤t->sighand->siglock);
|
|
sigorsets(¤t->blocked,¤t->blocked,&ka.sa.sa_mask);
|
|
sigaddset(¤t->blocked, signr);
|
|
recalc_sigpending();
|
|
spin_unlock_irq(¤t->sighand->siglock);
|
|
}
|
|
|
|
return 1;
|
|
}
|
|
|