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-rw-r--r--arch/blackfin/kernel/signal.c356
1 files changed, 356 insertions, 0 deletions
diff --git a/arch/blackfin/kernel/signal.c b/arch/blackfin/kernel/signal.c
new file mode 100644
index 0000000..316e65c
--- /dev/null
+++ b/arch/blackfin/kernel/signal.c
@@ -0,0 +1,356 @@
+/*
+ * File: arch/blackfin/kernel/signal.c
+ * Based on:
+ * Author:
+ *
+ * Created:
+ * Description:
+ *
+ * Modified:
+ * Copyright 2004-2006 Analog Devices Inc.
+ *
+ * Bugs: Enter bugs at http://blackfin.uclinux.org/
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, see the file COPYING, or write
+ * to the Free Software Foundation, Inc.,
+ * 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include <linux/signal.h>
+#include <linux/syscalls.h>
+#include <linux/ptrace.h>
+#include <linux/tty.h>
+#include <linux/personality.h>
+#include <linux/binfmts.h>
+#include <linux/freezer.h>
+
+#include <asm/uaccess.h>
+#include <asm/cacheflush.h>
+#include <asm/ucontext.h>
+
+#define _BLOCKABLE (~(sigmask(SIGKILL) | sigmask(SIGSTOP)))
+
+struct fdpic_func_descriptor {
+ unsigned long text;
+ unsigned long GOT;
+};
+
+struct rt_sigframe {
+ int sig;
+ struct siginfo *pinfo;
+ void *puc;
+ char retcode[8];
+ struct siginfo info;
+ struct ucontext uc;
+};
+
+asmlinkage int sys_sigaltstack(const stack_t * uss, stack_t * uoss)
+{
+ return do_sigaltstack(uss, uoss, rdusp());
+}
+
+static inline int
+rt_restore_sigcontext(struct pt_regs *regs, struct sigcontext *sc, int *pr0)
+{
+ unsigned long usp = 0;
+ int err = 0;
+
+#define RESTORE(x) err |= __get_user(regs->x, &sc->sc_##x)
+
+ /* restore passed registers */
+ RESTORE(r0); RESTORE(r1); RESTORE(r2); RESTORE(r3);
+ RESTORE(r4); RESTORE(r5); RESTORE(r6); RESTORE(r7);
+ RESTORE(p0); RESTORE(p1); RESTORE(p2); RESTORE(p3);
+ RESTORE(p4); RESTORE(p5);
+ err |= __get_user(usp, &sc->sc_usp);
+ wrusp(usp);
+ RESTORE(a0w); RESTORE(a1w);
+ RESTORE(a0x); RESTORE(a1x);
+ RESTORE(astat);
+ RESTORE(rets);
+ RESTORE(pc);
+ RESTORE(retx);
+ RESTORE(fp);
+ RESTORE(i0); RESTORE(i1); RESTORE(i2); RESTORE(i3);
+ RESTORE(m0); RESTORE(m1); RESTORE(m2); RESTORE(m3);
+ RESTORE(l0); RESTORE(l1); RESTORE(l2); RESTORE(l3);
+ RESTORE(b0); RESTORE(b1); RESTORE(b2); RESTORE(b3);
+ RESTORE(lc0); RESTORE(lc1);
+ RESTORE(lt0); RESTORE(lt1);
+ RESTORE(lb0); RESTORE(lb1);
+ RESTORE(seqstat);
+
+ regs->orig_p0 = -1; /* disable syscall checks */
+
+ *pr0 = regs->r0;
+ return err;
+}
+
+asmlinkage int do_rt_sigreturn(unsigned long __unused)
+{
+ struct pt_regs *regs = (struct pt_regs *)__unused;
+ unsigned long usp = rdusp();
+ struct rt_sigframe *frame = (struct rt_sigframe *)(usp);
+ sigset_t set;
+ int r0;
+
+ 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(&current->sighand->siglock);
+ current->blocked = set;
+ recalc_sigpending();
+ spin_unlock_irq(&current->sighand->siglock);
+
+ if (rt_restore_sigcontext(regs, &frame->uc.uc_mcontext, &r0))
+ goto badframe;
+
+ if (do_sigaltstack(&frame->uc.uc_stack, NULL, regs->usp) == -EFAULT)
+ goto badframe;
+
+ return r0;
+
+ badframe:
+ force_sig(SIGSEGV, current);
+ return 0;
+}
+
+static inline int rt_setup_sigcontext(struct sigcontext *sc, struct pt_regs *regs)
+{
+ int err = 0;
+
+#define SETUP(x) err |= __put_user(regs->x, &sc->sc_##x)
+
+ SETUP(r0); SETUP(r1); SETUP(r2); SETUP(r3);
+ SETUP(r4); SETUP(r5); SETUP(r6); SETUP(r7);
+ SETUP(p0); SETUP(p1); SETUP(p2); SETUP(p3);
+ SETUP(p4); SETUP(p5);
+ err |= __put_user(rdusp(), &sc->sc_usp);
+ SETUP(a0w); SETUP(a1w);
+ SETUP(a0x); SETUP(a1x);
+ SETUP(astat);
+ SETUP(rets);
+ SETUP(pc);
+ SETUP(retx);
+ SETUP(fp);
+ SETUP(i0); SETUP(i1); SETUP(i2); SETUP(i3);
+ SETUP(m0); SETUP(m1); SETUP(m2); SETUP(m3);
+ SETUP(l0); SETUP(l1); SETUP(l2); SETUP(l3);
+ SETUP(b0); SETUP(b1); SETUP(b2); SETUP(b3);
+ SETUP(lc0); SETUP(lc1);
+ SETUP(lt0); SETUP(lt1);
+ SETUP(lb0); SETUP(lb1);
+ SETUP(seqstat);
+
+ return err;
+}
+
+static inline void push_cache(unsigned long vaddr, unsigned int len)
+{
+ flush_icache_range(vaddr, vaddr + len);
+}
+
+static inline void *get_sigframe(struct k_sigaction *ka, struct pt_regs *regs,
+ size_t frame_size)
+{
+ unsigned long usp;
+
+ /* Default to using normal stack. */
+ usp = rdusp();
+
+ /* This is the X/Open sanctioned signal stack switching. */
+ if (ka->sa.sa_flags & SA_ONSTACK) {
+ if (!on_sig_stack(usp))
+ usp = current->sas_ss_sp + current->sas_ss_size;
+ }
+ return (void *)((usp - frame_size) & -8UL);
+}
+
+static int
+setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t * info,
+ sigset_t * set, struct pt_regs *regs)
+{
+ struct rt_sigframe *frame;
+ int err = 0;
+
+ frame = get_sigframe(ka, regs, sizeof(*frame));
+
+ err |= __put_user((current_thread_info()->exec_domain
+ && current_thread_info()->exec_domain->signal_invmap
+ && sig < 32
+ ? current_thread_info()->exec_domain->
+ signal_invmap[sig] : sig), &frame->sig);
+
+ err |= __put_user(&frame->info, &frame->pinfo);
+ err |= __put_user(&frame->uc, &frame->puc);
+ err |= copy_siginfo_to_user(&frame->info, info);
+
+ /* 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(rdusp()), &frame->uc.uc_stack.ss_flags);
+ err |= __put_user(current->sas_ss_size, &frame->uc.uc_stack.ss_size);
+ err |= rt_setup_sigcontext(&frame->uc.uc_mcontext, regs);
+ err |= copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set));
+
+ /* Set up to return from userspace. */
+ err |= __put_user(0x28, &(frame->retcode[0]));
+ err |= __put_user(0xe1, &(frame->retcode[1]));
+ err |= __put_user(0xad, &(frame->retcode[2]));
+ err |= __put_user(0x00, &(frame->retcode[3]));
+ err |= __put_user(0xa0, &(frame->retcode[4]));
+ err |= __put_user(0x00, &(frame->retcode[5]));
+
+ if (err)
+ goto give_sigsegv;
+
+ push_cache((unsigned long)&frame->retcode, sizeof(frame->retcode));
+
+ /* Set up registers for signal handler */
+ wrusp((unsigned long)frame);
+ if (get_personality & FDPIC_FUNCPTRS) {
+ struct fdpic_func_descriptor __user *funcptr =
+ (struct fdpic_func_descriptor *) ka->sa.sa_handler;
+ __get_user(regs->pc, &funcptr->text);
+ __get_user(regs->p3, &funcptr->GOT);
+ } else
+ regs->pc = (unsigned long)ka->sa.sa_handler;
+ regs->rets = (unsigned long)(frame->retcode);
+
+ regs->r0 = frame->sig;
+ regs->r1 = (unsigned long)(&frame->info);
+ regs->r2 = (unsigned long)(&frame->uc);
+
+ return 0;
+
+ give_sigsegv:
+ if (sig == SIGSEGV)
+ ka->sa.sa_handler = SIG_DFL;
+ force_sig(SIGSEGV, current);
+ return -EFAULT;
+}
+
+static inline void
+handle_restart(struct pt_regs *regs, struct k_sigaction *ka, int has_handler)
+{
+ switch (regs->r0) {
+ case -ERESTARTNOHAND:
+ if (!has_handler)
+ goto do_restart;
+ regs->r0 = -EINTR;
+ break;
+
+ case -ERESTARTSYS:
+ if (has_handler && !(ka->sa.sa_flags & SA_RESTART)) {
+ regs->r0 = -EINTR;
+ break;
+ }
+ /* fallthrough */
+ case -ERESTARTNOINTR:
+ do_restart:
+ regs->p0 = regs->orig_p0;
+ regs->r0 = regs->orig_r0;
+ regs->pc -= 2;
+ break;
+ }
+}
+
+/*
+ * OK, we're invoking a handler
+ */
+static int
+handle_signal(int sig, siginfo_t *info, struct k_sigaction *ka,
+ sigset_t *oldset, struct pt_regs *regs)
+{
+ int ret;
+
+ /* are we from a system call? to see pt_regs->orig_p0 */
+ if (regs->orig_p0 >= 0)
+ /* If so, check system call restarting.. */
+ handle_restart(regs, ka, 1);
+
+ /* set up the stack frame */
+ ret = setup_rt_frame(sig, ka, info, oldset, regs);
+
+ if (ret == 0) {
+ spin_lock_irq(&current->sighand->siglock);
+ sigorsets(&current->blocked, &current->blocked,
+ &ka->sa.sa_mask);
+ if (!(ka->sa.sa_flags & SA_NODEFER))
+ sigaddset(&current->blocked, sig);
+ recalc_sigpending();
+ spin_unlock_irq(&current->sighand->siglock);
+ }
+ return ret;
+}
+
+/*
+ * 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.
+ */
+asmlinkage void do_signal(struct pt_regs *regs)
+{
+ siginfo_t info;
+ int signr;
+ struct k_sigaction ka;
+ sigset_t *oldset;
+
+ current->thread.esp0 = (unsigned long)regs;
+
+ if (try_to_freeze())
+ goto no_signal;
+
+ if (test_thread_flag(TIF_RESTORE_SIGMASK))
+ oldset = &current->saved_sigmask;
+ else
+ oldset = &current->blocked;
+
+ signr = get_signal_to_deliver(&info, &ka, regs, NULL);
+ if (signr > 0) {
+ /* Whee! Actually deliver the signal. */
+ if (handle_signal(signr, &info, &ka, oldset, regs) == 0) {
+ /* a signal was successfully delivered; the saved
+ * sigmask will have been stored in the signal frame,
+ * and will be restored by sigreturn, so we can simply
+ * clear the TIF_RESTORE_SIGMASK flag */
+ if (test_thread_flag(TIF_RESTORE_SIGMASK))
+ clear_thread_flag(TIF_RESTORE_SIGMASK);
+ }
+
+ return;
+ }
+
+no_signal:
+ /* Did we come from a system call? */
+ if (regs->orig_p0 >= 0)
+ /* Restart the system call - no handlers present */
+ handle_restart(regs, NULL, 0);
+
+ /* if there's no signal to deliver, we just put the saved sigmask
+ * back */
+ if (test_thread_flag(TIF_RESTORE_SIGMASK)) {
+ clear_thread_flag(TIF_RESTORE_SIGMASK);
+ sigprocmask(SIG_SETMASK, &current->saved_sigmask, NULL);
+ }
+}
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