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authorRalf Baechle <ralf@linux-mips.org>2000-05-12 23:48:34 +0000
committerRalf Baechle <ralf@linux-mips.org>2000-05-12 23:48:34 +0000
commit7fd36ebeeec9244a7431bb010e6e3c5e4848a0d5 (patch)
tree5fb03a9aafdd1cec5f4f6ff7f1873174cb89b66c /arch/s390/kernel/signal.c
parentba2dacab305c598cd4c34a604f8e276bf5bab5ff (diff)
Merge with Linux 2.3.99-pre8. Linus must hate me, too man patches ;-)
Diffstat (limited to 'arch/s390/kernel/signal.c')
-rw-r--r--arch/s390/kernel/signal.c555
1 files changed, 555 insertions, 0 deletions
diff --git a/arch/s390/kernel/signal.c b/arch/s390/kernel/signal.c
new file mode 100644
index 000000000..fd1a5e58a
--- /dev/null
+++ b/arch/s390/kernel/signal.c
@@ -0,0 +1,555 @@
+/*
+ * arch/s390/kernel/signal.c
+ *
+ * S390 version
+ * Copyright (C) 1999 IBM Deutschland Entwicklung GmbH, IBM Corporation
+ * Author(s): Denis Joseph Barrow (djbarrow@de.ibm.com,barrow_dj@yahoo.com)
+ *
+ * Based on Intel version
+ *
+ * Copyright (C) 1991, 1992 Linus Torvalds
+ *
+ * 1997-11-28 Modified for POSIX.1b signals by Richard Henderson
+ */
+
+#include <linux/sched.h>
+#include <linux/mm.h>
+#include <linux/smp.h>
+#include <linux/smp_lock.h>
+#include <linux/kernel.h>
+#include <linux/signal.h>
+#include <linux/errno.h>
+#include <linux/wait.h>
+#include <linux/ptrace.h>
+#include <linux/unistd.h>
+#include <linux/stddef.h>
+#include <asm/ucontext.h>
+#include <asm/uaccess.h>
+
+#define DEBUG_SIG 0
+
+#define _BLOCKABLE (~(sigmask(SIGKILL) | sigmask(SIGSTOP)))
+
+/* pretcode & sig are used to store the return addr on Intel
+ & the signal no as the first parameter we do this differently
+ using gpr14 & gpr2. */
+
+#define SIGFRAME_COMMON \
+__u8 callee_used_stack[__SIGNAL_FRAMESIZE]; \
+struct sigcontext sc; \
+sigregs sregs; \
+__u8 retcode[S390_SYSCALL_SIZE];
+
+typedef struct
+{
+ SIGFRAME_COMMON
+} sigframe;
+
+typedef struct
+{
+ SIGFRAME_COMMON
+ struct siginfo info;
+ struct ucontext uc;
+} rt_sigframe;
+
+asmlinkage int sys_wait4(pid_t pid, unsigned long *stat_addr,
+ int options, unsigned long *ru);
+asmlinkage int FASTCALL(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(struct pt_regs * regs,int history0, int history1, old_sigset_t mask)
+{
+ sigset_t saveset;
+
+ mask &= _BLOCKABLE;
+ spin_lock_irq(&current->sigmask_lock);
+ saveset = current->blocked;
+ siginitset(&current->blocked, mask);
+ recalc_sigpending(current);
+ spin_unlock_irq(&current->sigmask_lock);
+ regs->gprs[2] = -EINTR;
+
+ while (1) {
+ current->state = TASK_INTERRUPTIBLE;
+ schedule();
+ if (do_signal(regs, &saveset))
+ return -EINTR;
+ }
+}
+
+asmlinkage int
+sys_rt_sigsuspend(struct pt_regs * regs,sigset_t *unewset, size_t sigsetsize)
+{
+ 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(&current->sigmask_lock);
+ saveset = current->blocked;
+ current->blocked = newset;
+ recalc_sigpending(current);
+ spin_unlock_irq(&current->sigmask_lock);
+ regs->gprs[2] = -EINTR;
+
+ while (1) {
+ current->state = TASK_INTERRUPTIBLE;
+ schedule();
+ if (do_signal(regs, &saveset))
+ return -EINTR;
+ }
+}
+
+asmlinkage int
+sys_sigaction(int sig, const struct old_sigaction *act,
+ struct old_sigaction *oact)
+{
+ struct k_sigaction new_ka, old_ka;
+ int ret;
+
+ if (act) {
+ old_sigset_t mask;
+ if (verify_area(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 (verify_area(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 *uss, stack_t *uoss)
+{
+ struct pt_regs *regs = (struct pt_regs *) &uss;
+ return do_sigaltstack(uss, uoss, regs->gprs[15]);
+}
+
+
+
+
+static int save_sigregs(struct pt_regs *regs,sigregs *sregs)
+{
+ int err;
+ s390_fp_regs fpregs;
+
+ err = __copy_to_user(&sregs->regs,regs,sizeof(s390_regs_common));
+ if(!err)
+ {
+ save_fp_regs(&fpregs);
+ err=__copy_to_user(&sregs->fpregs,&fpregs,sizeof(fpregs));
+ }
+ return(err);
+
+}
+
+static int restore_sigregs(struct pt_regs *regs,sigregs *sregs)
+{
+ int err;
+ s390_fp_regs fpregs;
+ psw_t saved_psw=regs->psw;
+ err=__copy_from_user(regs,&sregs->regs,sizeof(s390_regs_common));
+ if(!err)
+ {
+ regs->orig_gpr2 = -1; /* disable syscall checks */
+ regs->psw.mask=(saved_psw.mask&~PSW_MASK_DEBUGCHANGE)|
+ (regs->psw.mask&PSW_MASK_DEBUGCHANGE);
+ regs->psw.addr=(saved_psw.addr&~PSW_ADDR_DEBUGCHANGE)|
+ (regs->psw.addr&PSW_ADDR_DEBUGCHANGE);
+ err=__copy_from_user(&fpregs,&sregs->fpregs,sizeof(fpregs));
+ if(!err)
+ restore_fp_regs(&fpregs);
+ }
+ return(err);
+}
+
+static int
+restore_sigcontext(struct sigcontext *sc, pt_regs *regs,
+ sigregs *sregs,sigset_t *set)
+{
+ unsigned int err;
+
+ err=restore_sigregs(regs,sregs);
+ if(!err)
+ err=__copy_from_user(&set->sig,&sc->oldmask,SIGMASK_COPY_SIZE);
+ return(err);
+}
+
+int sigreturn_common(struct pt_regs *regs,int framesize)
+{
+ sigframe *frame = (sigframe *)regs->gprs[15];
+ sigset_t set;
+
+ if (verify_area(VERIFY_READ, frame, sizeof(*frame)))
+ return -1;
+ if (restore_sigcontext(&frame->sc,regs,&frame->sregs,&set))
+ return -1;
+ sigdelsetmask(&set, ~_BLOCKABLE);
+ spin_lock_irq(&current->sigmask_lock);
+ current->blocked = set;
+ recalc_sigpending(current);
+ spin_unlock_irq(&current->sigmask_lock);
+ return 0;
+}
+
+asmlinkage int sys_sigreturn(struct pt_regs *regs)
+{
+
+ if (sigreturn_common(regs,sizeof(sigframe)))
+ goto badframe;
+ return regs->gprs[2];
+
+badframe:
+ force_sig(SIGSEGV, current);
+ return 0;
+}
+
+asmlinkage int sys_rt_sigreturn(struct pt_regs *regs)
+{
+ rt_sigframe *frame = (rt_sigframe *)regs->gprs[15];
+ stack_t st;
+
+ if (sigreturn_common(regs,sizeof(rt_sigframe)))
+ goto badframe;
+ 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, regs->gprs[15]);
+ return regs->gprs[2];
+
+badframe:
+ force_sig(SIGSEGV, current);
+ return 0;
+}
+
+/*
+ * Set up a signal frame.
+ */
+
+
+/*
+ * Determine which stack to use..
+ */
+static inline void *
+get_sigframe(struct k_sigaction *ka, struct pt_regs * regs, size_t frame_size)
+{
+ unsigned long sp;
+
+ /* Default to using normal stack */
+ sp = regs->gprs[15];
+
+ /* This is the X/Open sanctioned signal stack switching. */
+ if (ka->sa.sa_flags & SA_ONSTACK) {
+ if (! on_sig_stack(sp))
+ sp = current->sas_ss_sp + current->sas_ss_size;
+ }
+
+ /* This is the legacy signal stack switching. */
+ else if (!user_mode(regs) &&
+ !(ka->sa.sa_flags & SA_RESTORER) &&
+ ka->sa.sa_restorer) {
+ sp = (unsigned long) ka->sa.sa_restorer;
+ }
+
+ return (void *)((sp - frame_size) & -8ul);
+}
+
+static void *setup_frame_common(int sig, struct k_sigaction *ka,
+ sigset_t *set, struct pt_regs * regs,
+ int frame_size,u16 retcode)
+{
+ sigframe *frame;
+ int err;
+
+ frame = get_sigframe(ka, regs,frame_size);
+ if (!access_ok(VERIFY_WRITE, frame,frame_size))
+ return 0;
+ err = save_sigregs(regs,&frame->sregs);
+ if(!err)
+ err=__put_user(&frame->sregs,&frame->sc.sregs);
+ if(!err)
+
+ err=__copy_to_user(&frame->sc.oldmask,&set->sig,SIGMASK_COPY_SIZE);
+ if(!err)
+ {
+ regs->gprs[2]=(current->exec_domain
+ && current->exec_domain->signal_invmap
+ && sig < 32
+ ? current->exec_domain->signal_invmap[sig]
+ : sig);
+ /* Set up registers for signal handler */
+ regs->gprs[15] = (addr_t)frame;
+ regs->psw.addr = FIX_PSW(ka->sa.sa_handler);
+ }
+ /* Set up to return from userspace. If provided, use a stub
+ already in userspace. */
+ if (ka->sa.sa_flags & SA_RESTORER) {
+ regs->gprs[14] = FIX_PSW(ka->sa.sa_restorer);
+ } else {
+ regs->gprs[14] = FIX_PSW(frame->retcode);
+ err |= __put_user(retcode, (u16 *)(frame->retcode));
+ }
+ return(err ? 0:frame);
+}
+
+static void setup_frame(int sig, struct k_sigaction *ka,
+ sigset_t *set, struct pt_regs * regs)
+{
+
+ if(!setup_frame_common(sig,ka,set,regs,sizeof(sigframe),
+ (S390_SYSCALL_OPCODE|__NR_sigreturn)))
+ goto give_sigsegv;
+#if DEBUG_SIG
+ printk("SIG deliver (%s:%d): sp=%p pc=%p ra=%p\n",
+ current->comm, current->pid, frame, regs->eip, frame->pretcode);
+#endif
+ return;
+
+give_sigsegv:
+ if (sig == SIGSEGV)
+ ka->sa.sa_handler = SIG_DFL;
+ force_sig(SIGSEGV, current);
+}
+
+static void setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info,
+ sigset_t *set, struct pt_regs * regs)
+{
+ rt_sigframe *frame;
+ addr_t orig_sp=regs->gprs[15];
+ int err;
+
+ if((frame=setup_frame_common(sig,ka,set,regs,sizeof(rt_sigframe),
+ (S390_SYSCALL_OPCODE|__NR_rt_sigreturn)))==0)
+ goto give_sigsegv;
+
+ err = __copy_to_user(&frame->info, info, sizeof(*info));
+
+ /* Create the ucontext. */
+ err |= __put_user(0, &frame->uc.uc_flags);
+ err |= __put_user(0, &frame->uc.uc_link);
+ err |= __put_user(current->sas_ss_sp, &frame->uc.uc_stack.ss_sp);
+ err |= __put_user(sas_ss_flags(orig_sp),
+ &frame->uc.uc_stack.ss_flags);
+ err |= __put_user(current->sas_ss_size, &frame->uc.uc_stack.ss_size);
+ regs->gprs[3] = (u32)&frame->info;
+ regs->gprs[4] = (u32)&frame->uc;
+
+ if (err)
+ goto give_sigsegv;
+
+#if DEBUG_SIG
+ printk("SIG deliver (%s:%d): sp=%p pc=%p ra=%p\n",
+ current->comm, current->pid, frame, regs->eip, frame->pretcode);
+#endif
+ return;
+
+give_sigsegv:
+ if (sig == SIGSEGV)
+ ka->sa.sa_handler = SIG_DFL;
+ force_sig(SIGSEGV, current);
+}
+
+/*
+ * 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)
+{
+ /* Are we from a system call? */
+ if (regs->orig_gpr2 >= 0) {
+ /* If so, check system call restarting.. */
+ switch (regs->gprs[2]) {
+ case -ERESTARTNOHAND:
+ regs->gprs[2] = -EINTR;
+ break;
+
+ case -ERESTARTSYS:
+ if (!(ka->sa.sa_flags & SA_RESTART)) {
+ regs->gprs[2] = -EINTR;
+ break;
+ }
+ /* fallthrough */
+ case -ERESTARTNOINTR:
+ regs->gprs[2] = regs->orig_gpr2;
+ regs->psw.addr -= 2;
+ }
+ }
+
+ /* 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);
+
+ if (ka->sa.sa_flags & SA_ONESHOT)
+ ka->sa.sa_handler = SIG_DFL;
+
+ if (!(ka->sa.sa_flags & SA_NODEFER)) {
+ spin_lock_irq(&current->sigmask_lock);
+ sigorsets(&current->blocked,&current->blocked,&ka->sa.sa_mask);
+ sigaddset(&current->blocked,sig);
+ recalc_sigpending(current);
+ spin_unlock_irq(&current->sigmask_lock);
+ }
+}
+
+/*
+ * 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;
+ 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 (!oldset)
+ oldset = &current->blocked;
+
+ for (;;) {
+ unsigned long signr;
+
+ spin_lock_irq(&current->sigmask_lock);
+ signr = dequeue_signal(&current->blocked, &info);
+ spin_unlock_irq(&current->sigmask_lock);
+
+ if (!signr)
+ break;
+
+ if ((current->flags & PF_PTRACED) && signr != SIGKILL) {
+ /* Let the debugger run. */
+ current->exit_code = signr;
+ current->state = TASK_STOPPED;
+ notify_parent(current, SIGCHLD);
+ schedule();
+
+ /* We're back. Did the debugger cancel the sig? */
+ if (!(signr = current->exit_code))
+ continue;
+ current->exit_code = 0;
+
+ /* The debugger continued. Ignore SIGSTOP. */
+ if (signr == SIGSTOP)
+ continue;
+
+ /* Update the siginfo structure. Is this good? */
+ if (signr != info.si_signo) {
+ info.si_signo = signr;
+ info.si_errno = 0;
+ info.si_code = SI_USER;
+ info.si_pid = current->p_pptr->pid;
+ info.si_uid = current->p_pptr->uid;
+ }
+
+ /* If the (new) signal is now blocked, requeue it. */
+ if (sigismember(&current->blocked, signr)) {
+ send_sig_info(signr, &info, current);
+ continue;
+ }
+ }
+
+ ka = &current->sig->action[signr-1];
+ if (ka->sa.sa_handler == SIG_IGN) {
+ if (signr != SIGCHLD)
+ continue;
+ /* Check for SIGCHLD: it's special. */
+ while (sys_wait4(-1, NULL, WNOHANG, NULL) > 0)
+ /* nothing */;
+ continue;
+ }
+
+ if (ka->sa.sa_handler == SIG_DFL) {
+ int exit_code = signr;
+
+ /* Init gets no signals it doesn't want. */
+ if (current->pid == 1)
+ continue;
+
+ switch (signr) {
+ case SIGCONT: case SIGCHLD: case SIGWINCH:
+ continue;
+
+ case SIGTSTP: case SIGTTIN: case SIGTTOU:
+ if (is_orphaned_pgrp(current->pgrp))
+ continue;
+ /* FALLTHRU */
+
+ case SIGSTOP:
+ current->state = TASK_STOPPED;
+ current->exit_code = signr;
+ if (!(current->p_pptr->sig->action[SIGCHLD-1].sa.sa_flags & SA_NOCLDSTOP))
+ notify_parent(current, SIGCHLD);
+ schedule();
+ continue;
+
+ case SIGQUIT: case SIGILL: case SIGTRAP:
+ case SIGABRT: case SIGFPE: case SIGSEGV:
+ if (do_coredump(signr, regs))
+ exit_code |= 0x80;
+ /* FALLTHRU */
+
+ default:
+ lock_kernel();
+ sigaddset(&current->signal, signr);
+ recalc_sigpending(current);
+ current->flags |= PF_SIGNALED;
+ do_exit(exit_code);
+ /* NOTREACHED */
+ }
+ }
+
+ /* Whee! Actually deliver the signal. */
+ handle_signal(signr, ka, &info, oldset, regs);
+ return 1;
+ }
+
+ /* Did we come from a system call? */
+ if ( regs->trap == 0x20 /* System Call! */ ) {
+ /* Restart the system call - no handlers present */
+ if (regs->gprs[2] == -ERESTARTNOHAND ||
+ regs->gprs[2] == -ERESTARTSYS ||
+ regs->gprs[2] == -ERESTARTNOINTR) {
+ regs->gprs[2] = regs->orig_gpr2;
+ regs->psw.addr -= 2;
+ }
+ }
+ return 0;
+}