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authorPaul Mundt <lethal@linux-sh.org>2007-11-10 20:07:57 +0900
committerPaul Mundt <lethal@linux-sh.org>2008-01-28 13:18:43 +0900
commitf7a7b15344e2bccdd1c73d42685edfe7d43ec5b7 (patch)
tree87280639daf814c9a818994926785faf9daded88 /arch/sh/kernel/signal_64.c
parent76168c21b78a0bd684d4687d14a2bd76bcf92762 (diff)
downloadop-kernel-dev-f7a7b15344e2bccdd1c73d42685edfe7d43ec5b7.zip
op-kernel-dev-f7a7b15344e2bccdd1c73d42685edfe7d43ec5b7.tar.gz
sh: Move in the SH-5 signal trampoline impl.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Diffstat (limited to 'arch/sh/kernel/signal_64.c')
-rw-r--r--arch/sh/kernel/signal_64.c754
1 files changed, 754 insertions, 0 deletions
diff --git a/arch/sh/kernel/signal_64.c b/arch/sh/kernel/signal_64.c
new file mode 100644
index 0000000..96ba81f
--- /dev/null
+++ b/arch/sh/kernel/signal_64.c
@@ -0,0 +1,754 @@
+/*
+ * 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>
+#include <asm/cacheflush.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(&current->sighand->siglock);
+ saveset = current->blocked;
+ siginitset(&current->blocked, mask);
+ recalc_sigpending();
+ spin_unlock_irq(&current->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(&current->sighand->siglock);
+ saveset = current->blocked;
+ current->blocked = newset;
+ recalc_sigpending();
+ spin_unlock_irq(&current->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(&current->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(&current->thread.fpu.hard);
+ release_fpu();
+ last_task_used_math = NULL;
+ regs->sr |= SR_FD;
+ }
+
+ err |= __copy_to_user(&sc->sc_fpregs[0], &current->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)
+{
+ return 0;
+}
+static inline int
+setup_sigcontext_fpu(struct pt_regs *regs, struct sigcontext __user *sc)
+{
+ return 0;
+}
+#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(&current->sighand->siglock);
+ current->blocked = set;
+ recalc_sigpending();
+ spin_unlock_irq(&current->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(&current->sighand->siglock);
+ current->blocked = set;
+ recalc_sigpending();
+ spin_unlock_irq(&current->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(&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);
+}
+
+/*
+ * 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 = &current->saved_sigmask;
+ else if (!oldset)
+ oldset = &current->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, &current->saved_sigmask, NULL);
+ }
+
+ return 0;
+}
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