powerpc: move ppc64/kernel/signal.c to arch/powerpc
authorStephen Rothwell <sfr@canb.auug.org.au>
Thu, 3 Nov 2005 04:26:23 +0000 (15:26 +1100)
committerStephen Rothwell <sfr@canb.auug.org.au>
Thu, 3 Nov 2005 05:03:20 +0000 (16:03 +1100)
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
arch/powerpc/kernel/Makefile
arch/powerpc/kernel/signal_64.c [new file with mode: 0644]
arch/ppc64/kernel/Makefile
arch/ppc64/kernel/signal.c [deleted file]

index 601ddbf1c20b06740f767ca09c3855d706d09e84..7a3e1155ac9a7bffb1ee73fb7ff747131f01d278 100644 (file)
@@ -13,7 +13,7 @@ endif
 obj-y                          := semaphore.o cputable.o ptrace.o syscalls.o \
                                   signal_32.o pmc.o
 obj-$(CONFIG_PPC64)            += setup_64.o binfmt_elf32.o sys_ppc32.o \
-                                  ptrace32.o systbl.o
+                                  signal_64.o ptrace32.o systbl.o
 obj-$(CONFIG_ALTIVEC)          += vecemu.o vector.o
 obj-$(CONFIG_POWER4)           += idle_power4.o
 obj-$(CONFIG_PPC_OF)           += of_device.o
diff --git a/arch/powerpc/kernel/signal_64.c b/arch/powerpc/kernel/signal_64.c
new file mode 100644 (file)
index 0000000..ec9d098
--- /dev/null
@@ -0,0 +1,581 @@
+/*
+ *  linux/arch/ppc64/kernel/signal.c
+ *
+ *  PowerPC version 
+ *    Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org)
+ *
+ *  Derived from "arch/i386/kernel/signal.c"
+ *    Copyright (C) 1991, 1992 Linus Torvalds
+ *    1997-11-28  Modified for POSIX.1b signals by Richard Henderson
+ *
+ *  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.
+ */
+
+#include <linux/config.h>
+#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/unistd.h>
+#include <linux/stddef.h>
+#include <linux/elf.h>
+#include <linux/ptrace.h>
+#include <linux/module.h>
+
+#include <asm/sigcontext.h>
+#include <asm/ucontext.h>
+#include <asm/uaccess.h>
+#include <asm/pgtable.h>
+#include <asm/ppcdebug.h>
+#include <asm/unistd.h>
+#include <asm/cacheflush.h>
+#include <asm/vdso.h>
+
+#define DEBUG_SIG 0
+
+#define _BLOCKABLE (~(sigmask(SIGKILL) | sigmask(SIGSTOP)))
+
+#define GP_REGS_SIZE   min(sizeof(elf_gregset_t), sizeof(struct pt_regs))
+#define FP_REGS_SIZE   sizeof(elf_fpregset_t)
+
+#define TRAMP_TRACEBACK        3
+#define TRAMP_SIZE     6
+
+/*
+ * When we have signals to deliver, we set up on the user stack,
+ * going down from the original stack pointer:
+ *     1) a rt_sigframe struct which contains the ucontext     
+ *     2) a gap of __SIGNAL_FRAMESIZE bytes which acts as a dummy caller
+ *        frame for the signal handler.
+ */
+
+struct rt_sigframe {
+       /* sys_rt_sigreturn requires the ucontext be the first field */
+       struct ucontext uc;
+       unsigned long _unused[2];
+       unsigned int tramp[TRAMP_SIZE];
+       struct siginfo *pinfo;
+       void *puc;
+       struct siginfo info;
+       /* 64 bit ABI allows for 288 bytes below sp before decrementing it. */
+       char abigap[288];
+} __attribute__ ((aligned (16)));
+
+
+/*
+ * Atomically swap in the new signal mask, and wait for a signal.
+ */
+long sys_rt_sigsuspend(sigset_t __user *unewset, size_t sigsetsize, int p3, int p4,
+                      int p6, int p7, 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);
+
+       regs->result = -EINTR;
+       regs->gpr[3] = EINTR;
+       regs->ccr |= 0x10000000;
+       while (1) {
+               current->state = TASK_INTERRUPTIBLE;
+               schedule();
+               if (do_signal(&saveset, regs))
+                       return 0;
+       }
+}
+
+long sys_sigaltstack(const stack_t __user *uss, stack_t __user *uoss, unsigned long r5,
+                    unsigned long r6, unsigned long r7, unsigned long r8,
+                    struct pt_regs *regs)
+{
+       return do_sigaltstack(uss, uoss, regs->gpr[1]);
+}
+
+
+/*
+ * Set up the sigcontext for the signal frame.
+ */
+
+static long setup_sigcontext(struct sigcontext __user *sc, struct pt_regs *regs,
+                int signr, sigset_t *set, unsigned long handler)
+{
+       /* When CONFIG_ALTIVEC is set, we _always_ setup v_regs even if the
+        * process never used altivec yet (MSR_VEC is zero in pt_regs of
+        * the context). This is very important because we must ensure we
+        * don't lose the VRSAVE content that may have been set prior to
+        * the process doing its first vector operation
+        * Userland shall check AT_HWCAP to know wether it can rely on the
+        * v_regs pointer or not
+        */
+#ifdef CONFIG_ALTIVEC
+       elf_vrreg_t __user *v_regs = (elf_vrreg_t __user *)(((unsigned long)sc->vmx_reserve + 15) & ~0xful);
+#endif
+       long err = 0;
+
+       flush_fp_to_thread(current);
+
+       /* Make sure signal doesn't get spurrious FP exceptions */
+       current->thread.fpscr.val = 0;
+
+#ifdef CONFIG_ALTIVEC
+       err |= __put_user(v_regs, &sc->v_regs);
+
+       /* save altivec registers */
+       if (current->thread.used_vr) {
+               flush_altivec_to_thread(current);
+               /* Copy 33 vec registers (vr0..31 and vscr) to the stack */
+               err |= __copy_to_user(v_regs, current->thread.vr, 33 * sizeof(vector128));
+               /* set MSR_VEC in the MSR value in the frame to indicate that sc->v_reg)
+                * contains valid data.
+                */
+               regs->msr |= MSR_VEC;
+       }
+       /* We always copy to/from vrsave, it's 0 if we don't have or don't
+        * use altivec.
+        */
+       err |= __put_user(current->thread.vrsave, (u32 __user *)&v_regs[33]);
+#else /* CONFIG_ALTIVEC */
+       err |= __put_user(0, &sc->v_regs);
+#endif /* CONFIG_ALTIVEC */
+       err |= __put_user(&sc->gp_regs, &sc->regs);
+       err |= __copy_to_user(&sc->gp_regs, regs, GP_REGS_SIZE);
+       err |= __copy_to_user(&sc->fp_regs, &current->thread.fpr, FP_REGS_SIZE);
+       err |= __put_user(signr, &sc->signal);
+       err |= __put_user(handler, &sc->handler);
+       if (set != NULL)
+               err |=  __put_user(set->sig[0], &sc->oldmask);
+
+       return err;
+}
+
+/*
+ * Restore the sigcontext from the signal frame.
+ */
+
+static long restore_sigcontext(struct pt_regs *regs, sigset_t *set, int sig,
+                             struct sigcontext __user *sc)
+{
+#ifdef CONFIG_ALTIVEC
+       elf_vrreg_t __user *v_regs;
+#endif
+       unsigned long err = 0;
+       unsigned long save_r13 = 0;
+       elf_greg_t *gregs = (elf_greg_t *)regs;
+#ifdef CONFIG_ALTIVEC
+       unsigned long msr;
+#endif
+       int i;
+
+       /* If this is not a signal return, we preserve the TLS in r13 */
+       if (!sig)
+               save_r13 = regs->gpr[13];
+
+       /* copy everything before MSR */
+       err |= __copy_from_user(regs, &sc->gp_regs,
+                               PT_MSR*sizeof(unsigned long));
+
+       /* skip MSR and SOFTE */
+       for (i = PT_MSR+1; i <= PT_RESULT; i++) {
+               if (i == PT_SOFTE)
+                       continue;
+               err |= __get_user(gregs[i], &sc->gp_regs[i]);
+       }
+
+       if (!sig)
+               regs->gpr[13] = save_r13;
+       err |= __copy_from_user(&current->thread.fpr, &sc->fp_regs, FP_REGS_SIZE);
+       if (set != NULL)
+               err |=  __get_user(set->sig[0], &sc->oldmask);
+
+#ifdef CONFIG_ALTIVEC
+       err |= __get_user(v_regs, &sc->v_regs);
+       err |= __get_user(msr, &sc->gp_regs[PT_MSR]);
+       if (err)
+               return err;
+       /* Copy 33 vec registers (vr0..31 and vscr) from the stack */
+       if (v_regs != 0 && (msr & MSR_VEC) != 0)
+               err |= __copy_from_user(current->thread.vr, v_regs,
+                                       33 * sizeof(vector128));
+       else if (current->thread.used_vr)
+               memset(current->thread.vr, 0, 33 * sizeof(vector128));
+       /* Always get VRSAVE back */
+       if (v_regs != 0)
+               err |= __get_user(current->thread.vrsave, (u32 __user *)&v_regs[33]);
+       else
+               current->thread.vrsave = 0;
+#endif /* CONFIG_ALTIVEC */
+
+#ifndef CONFIG_SMP
+       preempt_disable();
+       if (last_task_used_math == current)
+               last_task_used_math = NULL;
+       if (last_task_used_altivec == current)
+               last_task_used_altivec = NULL;
+       preempt_enable();
+#endif
+       /* Force reload of FP/VEC */
+       regs->msr &= ~(MSR_FP | MSR_FE0 | MSR_FE1 | MSR_VEC);
+
+       return err;
+}
+
+/*
+ * Allocate space for the signal frame
+ */
+static inline void __user * get_sigframe(struct k_sigaction *ka, struct pt_regs *regs,
+                                 size_t frame_size)
+{
+        unsigned long newsp;
+
+        /* Default to using normal stack */
+        newsp = regs->gpr[1];
+
+       if (ka->sa.sa_flags & SA_ONSTACK) {
+               if (! on_sig_stack(regs->gpr[1]))
+                       newsp = (current->sas_ss_sp + current->sas_ss_size);
+       }
+
+        return (void __user *)((newsp - frame_size) & -16ul);
+}
+
+/*
+ * Setup the trampoline code on the stack
+ */
+static long setup_trampoline(unsigned int syscall, unsigned int __user *tramp)
+{
+       int i;
+       long err = 0;
+
+       /* addi r1, r1, __SIGNAL_FRAMESIZE  # Pop the dummy stackframe */
+       err |= __put_user(0x38210000UL | (__SIGNAL_FRAMESIZE & 0xffff), &tramp[0]);
+       /* li r0, __NR_[rt_]sigreturn| */
+       err |= __put_user(0x38000000UL | (syscall & 0xffff), &tramp[1]);
+       /* sc */
+       err |= __put_user(0x44000002UL, &tramp[2]);
+
+       /* Minimal traceback info */
+       for (i=TRAMP_TRACEBACK; i < TRAMP_SIZE ;i++)
+               err |= __put_user(0, &tramp[i]);
+
+       if (!err)
+               flush_icache_range((unsigned long) &tramp[0],
+                          (unsigned long) &tramp[TRAMP_SIZE]);
+
+       return err;
+}
+
+/*
+ * Restore the user process's signal mask (also used by signal32.c)
+ */
+void restore_sigmask(sigset_t *set)
+{
+       sigdelsetmask(set, ~_BLOCKABLE);
+       spin_lock_irq(&current->sighand->siglock);
+       current->blocked = *set;
+       recalc_sigpending();
+       spin_unlock_irq(&current->sighand->siglock);
+}
+
+
+/*
+ * Handle {get,set,swap}_context operations
+ */
+int sys_swapcontext(struct ucontext __user *old_ctx,
+                   struct ucontext __user *new_ctx,
+                   long ctx_size, long r6, long r7, long r8, struct pt_regs *regs)
+{
+       unsigned char tmp;
+       sigset_t set;
+
+       /* Context size is for future use. Right now, we only make sure
+        * we are passed something we understand
+        */
+       if (ctx_size < sizeof(struct ucontext))
+               return -EINVAL;
+
+       if (old_ctx != NULL) {
+               if (!access_ok(VERIFY_WRITE, old_ctx, sizeof(*old_ctx))
+                   || setup_sigcontext(&old_ctx->uc_mcontext, regs, 0, NULL, 0)
+                   || __copy_to_user(&old_ctx->uc_sigmask,
+                                     &current->blocked, sizeof(sigset_t)))
+                       return -EFAULT;
+       }
+       if (new_ctx == NULL)
+               return 0;
+       if (!access_ok(VERIFY_READ, new_ctx, sizeof(*new_ctx))
+           || __get_user(tmp, (u8 __user *) new_ctx)
+           || __get_user(tmp, (u8 __user *) (new_ctx + 1) - 1))
+               return -EFAULT;
+
+       /*
+        * 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 (__copy_from_user(&set, &new_ctx->uc_sigmask, sizeof(set)))
+               do_exit(SIGSEGV);
+       restore_sigmask(&set);
+       if (restore_sigcontext(regs, NULL, 0, &new_ctx->uc_mcontext))
+               do_exit(SIGSEGV);
+
+       /* This returns like rt_sigreturn */
+       return 0;
+}
+
+
+/*
+ * Do a signal return; undo the signal stack.
+ */
+
+int sys_rt_sigreturn(unsigned long r3, unsigned long r4, unsigned long r5,
+                    unsigned long r6, unsigned long r7, unsigned long r8,
+                    struct pt_regs *regs)
+{
+       struct ucontext __user *uc = (struct ucontext __user *)regs->gpr[1];
+       sigset_t set;
+
+       /* Always make any pending restarted system calls return -EINTR */
+       current_thread_info()->restart_block.fn = do_no_restart_syscall;
+
+       if (!access_ok(VERIFY_READ, uc, sizeof(*uc)))
+               goto badframe;
+
+       if (__copy_from_user(&set, &uc->uc_sigmask, sizeof(set)))
+               goto badframe;
+       restore_sigmask(&set);
+       if (restore_sigcontext(regs, NULL, 1, &uc->uc_mcontext))
+               goto badframe;
+
+       /* do_sigaltstack expects a __user pointer and won't modify
+        * what's in there anyway
+        */
+       do_sigaltstack(&uc->uc_stack, NULL, regs->gpr[1]);
+
+       return regs->result;
+
+badframe:
+#if DEBUG_SIG
+       printk("badframe in sys_rt_sigreturn, regs=%p uc=%p &uc->uc_mcontext=%p\n",
+              regs, uc, &uc->uc_mcontext);
+#endif
+       force_sig(SIGSEGV, current);
+       return 0;
+}
+
+static int setup_rt_frame(int signr, struct k_sigaction *ka, siginfo_t *info,
+               sigset_t *set, struct pt_regs *regs)
+{
+       /* Handler is *really* a pointer to the function descriptor for
+        * the signal routine.  The first entry in the function
+        * descriptor is the entry address of signal and the second
+        * entry is the TOC value we need to use.
+        */
+       func_descr_t __user *funct_desc_ptr;
+       struct rt_sigframe __user *frame;
+       unsigned long newsp = 0;
+       long err = 0;
+
+       frame = get_sigframe(ka, regs, sizeof(*frame));
+
+       if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
+               goto badframe;
+
+       err |= __put_user(&frame->info, &frame->pinfo);
+       err |= __put_user(&frame->uc, &frame->puc);
+       err |= copy_siginfo_to_user(&frame->info, info);
+       if (err)
+               goto badframe;
+
+       /* 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(regs->gpr[1]),
+                         &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, signr, NULL,
+                               (unsigned long)ka->sa.sa_handler);
+       err |= __copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set));
+       if (err)
+               goto badframe;
+
+       /* Set up to return from userspace. */
+       if (vdso64_rt_sigtramp && current->thread.vdso_base) {
+               regs->link = current->thread.vdso_base + vdso64_rt_sigtramp;
+       } else {
+               err |= setup_trampoline(__NR_rt_sigreturn, &frame->tramp[0]);
+               if (err)
+                       goto badframe;
+               regs->link = (unsigned long) &frame->tramp[0];
+       }
+       funct_desc_ptr = (func_descr_t __user *) ka->sa.sa_handler;
+
+       /* Allocate a dummy caller frame for the signal handler. */
+       newsp = (unsigned long)frame - __SIGNAL_FRAMESIZE;
+       err |= put_user(regs->gpr[1], (unsigned long __user *)newsp);
+
+       /* Set up "regs" so we "return" to the signal handler. */
+       err |= get_user(regs->nip, &funct_desc_ptr->entry);
+       regs->gpr[1] = newsp;
+       err |= get_user(regs->gpr[2], &funct_desc_ptr->toc);
+       regs->gpr[3] = signr;
+       regs->result = 0;
+       if (ka->sa.sa_flags & SA_SIGINFO) {
+               err |= get_user(regs->gpr[4], (unsigned long __user *)&frame->pinfo);
+               err |= get_user(regs->gpr[5], (unsigned long __user *)&frame->puc);
+               regs->gpr[6] = (unsigned long) frame;
+       } else {
+               regs->gpr[4] = (unsigned long)&frame->uc.uc_mcontext;
+       }
+       if (err)
+               goto badframe;
+
+       if (test_thread_flag(TIF_SINGLESTEP))
+               ptrace_notify(SIGTRAP);
+
+       return 1;
+
+badframe:
+#if DEBUG_SIG
+       printk("badframe in setup_rt_frame, regs=%p frame=%p newsp=%lx\n",
+              regs, frame, newsp);
+#endif
+       force_sigsegv(signr, current);
+       return 0;
+}
+
+
+/*
+ * OK, we're invoking a handler
+ */
+static int handle_signal(unsigned long sig, struct k_sigaction *ka,
+                        siginfo_t *info, sigset_t *oldset, struct pt_regs *regs)
+{
+       int ret;
+
+       /* Set up Signal Frame */
+       ret = setup_rt_frame(sig, ka, info, oldset, regs);
+
+       if (ret) {
+               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;
+}
+
+static inline void syscall_restart(struct pt_regs *regs, struct k_sigaction *ka)
+{
+       switch ((int)regs->result) {
+       case -ERESTART_RESTARTBLOCK:
+       case -ERESTARTNOHAND:
+               /* ERESTARTNOHAND means that the syscall should only be
+                * restarted if there was no handler for the signal, and since
+                * we only get here if there is a handler, we dont restart.
+                */
+               regs->result = -EINTR;
+               break;
+       case -ERESTARTSYS:
+               /* ERESTARTSYS means to restart the syscall if there is no
+                * handler or the handler was registered with SA_RESTART
+                */
+               if (!(ka->sa.sa_flags & SA_RESTART)) {
+                       regs->result = -EINTR;
+                       break;
+               }
+               /* fallthrough */
+       case -ERESTARTNOINTR:
+               /* ERESTARTNOINTR means that the syscall should be
+                * called again after the signal handler returns.
+                */
+               regs->gpr[3] = regs->orig_gpr3;
+               regs->nip -= 4;
+               regs->result = 0;
+               break;
+       }
+}
+
+/*
+ * 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;
+       int signr;
+       struct k_sigaction ka;
+
+       /*
+        * If the current thread is 32 bit - invoke the
+        * 32 bit signal handling code
+        */
+       if (test_thread_flag(TIF_32BIT))
+               return do_signal32(oldset, regs);
+
+       if (!oldset)
+               oldset = &current->blocked;
+
+       signr = get_signal_to_deliver(&info, &ka, regs, NULL);
+       if (signr > 0) {
+               /* Whee!  Actually deliver the signal.  */
+               if (TRAP(regs) == 0x0C00)
+                       syscall_restart(regs, &ka);
+
+               /*
+                * Reenable the DABR before delivering the signal to
+                * user space. The DABR will have been cleared if it
+                * triggered inside the kernel.
+                */
+               if (current->thread.dabr)
+                       set_dabr(current->thread.dabr);
+
+               return handle_signal(signr, &ka, &info, oldset, regs);
+       }
+
+       if (TRAP(regs) == 0x0C00) {     /* System Call! */
+               if ((int)regs->result == -ERESTARTNOHAND ||
+                   (int)regs->result == -ERESTARTSYS ||
+                   (int)regs->result == -ERESTARTNOINTR) {
+                       regs->gpr[3] = regs->orig_gpr3;
+                       regs->nip -= 4; /* Back up & retry system call */
+                       regs->result = 0;
+               } else if ((int)regs->result == -ERESTART_RESTARTBLOCK) {
+                       regs->gpr[0] = __NR_restart_syscall;
+                       regs->nip -= 4;
+                       regs->result = 0;
+               }
+       }
+
+       return 0;
+}
+EXPORT_SYMBOL(do_signal);
index 74892ad032ba8af71b2df9d451ce188f75dc88ef..430cb3900a072eb56909f8f00d84e6803af63d16 100644 (file)
@@ -12,7 +12,6 @@ obj-y               :=        misc.o prom.o
 endif
 
 obj-y               += irq.o idle.o dma.o \
-                       signal.o \
                        align.o pacaData.o \
                        udbg.o ioctl32.o \
                        rtc.o \
diff --git a/arch/ppc64/kernel/signal.c b/arch/ppc64/kernel/signal.c
deleted file mode 100644 (file)
index ec9d098..0000000
+++ /dev/null
@@ -1,581 +0,0 @@
-/*
- *  linux/arch/ppc64/kernel/signal.c
- *
- *  PowerPC version 
- *    Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org)
- *
- *  Derived from "arch/i386/kernel/signal.c"
- *    Copyright (C) 1991, 1992 Linus Torvalds
- *    1997-11-28  Modified for POSIX.1b signals by Richard Henderson
- *
- *  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.
- */
-
-#include <linux/config.h>
-#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/unistd.h>
-#include <linux/stddef.h>
-#include <linux/elf.h>
-#include <linux/ptrace.h>
-#include <linux/module.h>
-
-#include <asm/sigcontext.h>
-#include <asm/ucontext.h>
-#include <asm/uaccess.h>
-#include <asm/pgtable.h>
-#include <asm/ppcdebug.h>
-#include <asm/unistd.h>
-#include <asm/cacheflush.h>
-#include <asm/vdso.h>
-
-#define DEBUG_SIG 0
-
-#define _BLOCKABLE (~(sigmask(SIGKILL) | sigmask(SIGSTOP)))
-
-#define GP_REGS_SIZE   min(sizeof(elf_gregset_t), sizeof(struct pt_regs))
-#define FP_REGS_SIZE   sizeof(elf_fpregset_t)
-
-#define TRAMP_TRACEBACK        3
-#define TRAMP_SIZE     6
-
-/*
- * When we have signals to deliver, we set up on the user stack,
- * going down from the original stack pointer:
- *     1) a rt_sigframe struct which contains the ucontext     
- *     2) a gap of __SIGNAL_FRAMESIZE bytes which acts as a dummy caller
- *        frame for the signal handler.
- */
-
-struct rt_sigframe {
-       /* sys_rt_sigreturn requires the ucontext be the first field */
-       struct ucontext uc;
-       unsigned long _unused[2];
-       unsigned int tramp[TRAMP_SIZE];
-       struct siginfo *pinfo;
-       void *puc;
-       struct siginfo info;
-       /* 64 bit ABI allows for 288 bytes below sp before decrementing it. */
-       char abigap[288];
-} __attribute__ ((aligned (16)));
-
-
-/*
- * Atomically swap in the new signal mask, and wait for a signal.
- */
-long sys_rt_sigsuspend(sigset_t __user *unewset, size_t sigsetsize, int p3, int p4,
-                      int p6, int p7, 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);
-
-       regs->result = -EINTR;
-       regs->gpr[3] = EINTR;
-       regs->ccr |= 0x10000000;
-       while (1) {
-               current->state = TASK_INTERRUPTIBLE;
-               schedule();
-               if (do_signal(&saveset, regs))
-                       return 0;
-       }
-}
-
-long sys_sigaltstack(const stack_t __user *uss, stack_t __user *uoss, unsigned long r5,
-                    unsigned long r6, unsigned long r7, unsigned long r8,
-                    struct pt_regs *regs)
-{
-       return do_sigaltstack(uss, uoss, regs->gpr[1]);
-}
-
-
-/*
- * Set up the sigcontext for the signal frame.
- */
-
-static long setup_sigcontext(struct sigcontext __user *sc, struct pt_regs *regs,
-                int signr, sigset_t *set, unsigned long handler)
-{
-       /* When CONFIG_ALTIVEC is set, we _always_ setup v_regs even if the
-        * process never used altivec yet (MSR_VEC is zero in pt_regs of
-        * the context). This is very important because we must ensure we
-        * don't lose the VRSAVE content that may have been set prior to
-        * the process doing its first vector operation
-        * Userland shall check AT_HWCAP to know wether it can rely on the
-        * v_regs pointer or not
-        */
-#ifdef CONFIG_ALTIVEC
-       elf_vrreg_t __user *v_regs = (elf_vrreg_t __user *)(((unsigned long)sc->vmx_reserve + 15) & ~0xful);
-#endif
-       long err = 0;
-
-       flush_fp_to_thread(current);
-
-       /* Make sure signal doesn't get spurrious FP exceptions */
-       current->thread.fpscr.val = 0;
-
-#ifdef CONFIG_ALTIVEC
-       err |= __put_user(v_regs, &sc->v_regs);
-
-       /* save altivec registers */
-       if (current->thread.used_vr) {
-               flush_altivec_to_thread(current);
-               /* Copy 33 vec registers (vr0..31 and vscr) to the stack */
-               err |= __copy_to_user(v_regs, current->thread.vr, 33 * sizeof(vector128));
-               /* set MSR_VEC in the MSR value in the frame to indicate that sc->v_reg)
-                * contains valid data.
-                */
-               regs->msr |= MSR_VEC;
-       }
-       /* We always copy to/from vrsave, it's 0 if we don't have or don't
-        * use altivec.
-        */
-       err |= __put_user(current->thread.vrsave, (u32 __user *)&v_regs[33]);
-#else /* CONFIG_ALTIVEC */
-       err |= __put_user(0, &sc->v_regs);
-#endif /* CONFIG_ALTIVEC */
-       err |= __put_user(&sc->gp_regs, &sc->regs);
-       err |= __copy_to_user(&sc->gp_regs, regs, GP_REGS_SIZE);
-       err |= __copy_to_user(&sc->fp_regs, &current->thread.fpr, FP_REGS_SIZE);
-       err |= __put_user(signr, &sc->signal);
-       err |= __put_user(handler, &sc->handler);
-       if (set != NULL)
-               err |=  __put_user(set->sig[0], &sc->oldmask);
-
-       return err;
-}
-
-/*
- * Restore the sigcontext from the signal frame.
- */
-
-static long restore_sigcontext(struct pt_regs *regs, sigset_t *set, int sig,
-                             struct sigcontext __user *sc)
-{
-#ifdef CONFIG_ALTIVEC
-       elf_vrreg_t __user *v_regs;
-#endif
-       unsigned long err = 0;
-       unsigned long save_r13 = 0;
-       elf_greg_t *gregs = (elf_greg_t *)regs;
-#ifdef CONFIG_ALTIVEC
-       unsigned long msr;
-#endif
-       int i;
-
-       /* If this is not a signal return, we preserve the TLS in r13 */
-       if (!sig)
-               save_r13 = regs->gpr[13];
-
-       /* copy everything before MSR */
-       err |= __copy_from_user(regs, &sc->gp_regs,
-                               PT_MSR*sizeof(unsigned long));
-
-       /* skip MSR and SOFTE */
-       for (i = PT_MSR+1; i <= PT_RESULT; i++) {
-               if (i == PT_SOFTE)
-                       continue;
-               err |= __get_user(gregs[i], &sc->gp_regs[i]);
-       }
-
-       if (!sig)
-               regs->gpr[13] = save_r13;
-       err |= __copy_from_user(&current->thread.fpr, &sc->fp_regs, FP_REGS_SIZE);
-       if (set != NULL)
-               err |=  __get_user(set->sig[0], &sc->oldmask);
-
-#ifdef CONFIG_ALTIVEC
-       err |= __get_user(v_regs, &sc->v_regs);
-       err |= __get_user(msr, &sc->gp_regs[PT_MSR]);
-       if (err)
-               return err;
-       /* Copy 33 vec registers (vr0..31 and vscr) from the stack */
-       if (v_regs != 0 && (msr & MSR_VEC) != 0)
-               err |= __copy_from_user(current->thread.vr, v_regs,
-                                       33 * sizeof(vector128));
-       else if (current->thread.used_vr)
-               memset(current->thread.vr, 0, 33 * sizeof(vector128));
-       /* Always get VRSAVE back */
-       if (v_regs != 0)
-               err |= __get_user(current->thread.vrsave, (u32 __user *)&v_regs[33]);
-       else
-               current->thread.vrsave = 0;
-#endif /* CONFIG_ALTIVEC */
-
-#ifndef CONFIG_SMP
-       preempt_disable();
-       if (last_task_used_math == current)
-               last_task_used_math = NULL;
-       if (last_task_used_altivec == current)
-               last_task_used_altivec = NULL;
-       preempt_enable();
-#endif
-       /* Force reload of FP/VEC */
-       regs->msr &= ~(MSR_FP | MSR_FE0 | MSR_FE1 | MSR_VEC);
-
-       return err;
-}
-
-/*
- * Allocate space for the signal frame
- */
-static inline void __user * get_sigframe(struct k_sigaction *ka, struct pt_regs *regs,
-                                 size_t frame_size)
-{
-        unsigned long newsp;
-
-        /* Default to using normal stack */
-        newsp = regs->gpr[1];
-
-       if (ka->sa.sa_flags & SA_ONSTACK) {
-               if (! on_sig_stack(regs->gpr[1]))
-                       newsp = (current->sas_ss_sp + current->sas_ss_size);
-       }
-
-        return (void __user *)((newsp - frame_size) & -16ul);
-}
-
-/*
- * Setup the trampoline code on the stack
- */
-static long setup_trampoline(unsigned int syscall, unsigned int __user *tramp)
-{
-       int i;
-       long err = 0;
-
-       /* addi r1, r1, __SIGNAL_FRAMESIZE  # Pop the dummy stackframe */
-       err |= __put_user(0x38210000UL | (__SIGNAL_FRAMESIZE & 0xffff), &tramp[0]);
-       /* li r0, __NR_[rt_]sigreturn| */
-       err |= __put_user(0x38000000UL | (syscall & 0xffff), &tramp[1]);
-       /* sc */
-       err |= __put_user(0x44000002UL, &tramp[2]);
-
-       /* Minimal traceback info */
-       for (i=TRAMP_TRACEBACK; i < TRAMP_SIZE ;i++)
-               err |= __put_user(0, &tramp[i]);
-
-       if (!err)
-               flush_icache_range((unsigned long) &tramp[0],
-                          (unsigned long) &tramp[TRAMP_SIZE]);
-
-       return err;
-}
-
-/*
- * Restore the user process's signal mask (also used by signal32.c)
- */
-void restore_sigmask(sigset_t *set)
-{
-       sigdelsetmask(set, ~_BLOCKABLE);
-       spin_lock_irq(&current->sighand->siglock);
-       current->blocked = *set;
-       recalc_sigpending();
-       spin_unlock_irq(&current->sighand->siglock);
-}
-
-
-/*
- * Handle {get,set,swap}_context operations
- */
-int sys_swapcontext(struct ucontext __user *old_ctx,
-                   struct ucontext __user *new_ctx,
-                   long ctx_size, long r6, long r7, long r8, struct pt_regs *regs)
-{
-       unsigned char tmp;
-       sigset_t set;
-
-       /* Context size is for future use. Right now, we only make sure
-        * we are passed something we understand
-        */
-       if (ctx_size < sizeof(struct ucontext))
-               return -EINVAL;
-
-       if (old_ctx != NULL) {
-               if (!access_ok(VERIFY_WRITE, old_ctx, sizeof(*old_ctx))
-                   || setup_sigcontext(&old_ctx->uc_mcontext, regs, 0, NULL, 0)
-                   || __copy_to_user(&old_ctx->uc_sigmask,
-                                     &current->blocked, sizeof(sigset_t)))
-                       return -EFAULT;
-       }
-       if (new_ctx == NULL)
-               return 0;
-       if (!access_ok(VERIFY_READ, new_ctx, sizeof(*new_ctx))
-           || __get_user(tmp, (u8 __user *) new_ctx)
-           || __get_user(tmp, (u8 __user *) (new_ctx + 1) - 1))
-               return -EFAULT;
-
-       /*
-        * 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 (__copy_from_user(&set, &new_ctx->uc_sigmask, sizeof(set)))
-               do_exit(SIGSEGV);
-       restore_sigmask(&set);
-       if (restore_sigcontext(regs, NULL, 0, &new_ctx->uc_mcontext))
-               do_exit(SIGSEGV);
-
-       /* This returns like rt_sigreturn */
-       return 0;
-}
-
-
-/*
- * Do a signal return; undo the signal stack.
- */
-
-int sys_rt_sigreturn(unsigned long r3, unsigned long r4, unsigned long r5,
-                    unsigned long r6, unsigned long r7, unsigned long r8,
-                    struct pt_regs *regs)
-{
-       struct ucontext __user *uc = (struct ucontext __user *)regs->gpr[1];
-       sigset_t set;
-
-       /* Always make any pending restarted system calls return -EINTR */
-       current_thread_info()->restart_block.fn = do_no_restart_syscall;
-
-       if (!access_ok(VERIFY_READ, uc, sizeof(*uc)))
-               goto badframe;
-
-       if (__copy_from_user(&set, &uc->uc_sigmask, sizeof(set)))
-               goto badframe;
-       restore_sigmask(&set);
-       if (restore_sigcontext(regs, NULL, 1, &uc->uc_mcontext))
-               goto badframe;
-
-       /* do_sigaltstack expects a __user pointer and won't modify
-        * what's in there anyway
-        */
-       do_sigaltstack(&uc->uc_stack, NULL, regs->gpr[1]);
-
-       return regs->result;
-
-badframe:
-#if DEBUG_SIG
-       printk("badframe in sys_rt_sigreturn, regs=%p uc=%p &uc->uc_mcontext=%p\n",
-              regs, uc, &uc->uc_mcontext);
-#endif
-       force_sig(SIGSEGV, current);
-       return 0;
-}
-
-static int setup_rt_frame(int signr, struct k_sigaction *ka, siginfo_t *info,
-               sigset_t *set, struct pt_regs *regs)
-{
-       /* Handler is *really* a pointer to the function descriptor for
-        * the signal routine.  The first entry in the function
-        * descriptor is the entry address of signal and the second
-        * entry is the TOC value we need to use.
-        */
-       func_descr_t __user *funct_desc_ptr;
-       struct rt_sigframe __user *frame;
-       unsigned long newsp = 0;
-       long err = 0;
-
-       frame = get_sigframe(ka, regs, sizeof(*frame));
-
-       if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
-               goto badframe;
-
-       err |= __put_user(&frame->info, &frame->pinfo);
-       err |= __put_user(&frame->uc, &frame->puc);
-       err |= copy_siginfo_to_user(&frame->info, info);
-       if (err)
-               goto badframe;
-
-       /* 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(regs->gpr[1]),
-                         &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, signr, NULL,
-                               (unsigned long)ka->sa.sa_handler);
-       err |= __copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set));
-       if (err)
-               goto badframe;
-
-       /* Set up to return from userspace. */
-       if (vdso64_rt_sigtramp && current->thread.vdso_base) {
-               regs->link = current->thread.vdso_base + vdso64_rt_sigtramp;
-       } else {
-               err |= setup_trampoline(__NR_rt_sigreturn, &frame->tramp[0]);
-               if (err)
-                       goto badframe;
-               regs->link = (unsigned long) &frame->tramp[0];
-       }
-       funct_desc_ptr = (func_descr_t __user *) ka->sa.sa_handler;
-
-       /* Allocate a dummy caller frame for the signal handler. */
-       newsp = (unsigned long)frame - __SIGNAL_FRAMESIZE;
-       err |= put_user(regs->gpr[1], (unsigned long __user *)newsp);
-
-       /* Set up "regs" so we "return" to the signal handler. */
-       err |= get_user(regs->nip, &funct_desc_ptr->entry);
-       regs->gpr[1] = newsp;
-       err |= get_user(regs->gpr[2], &funct_desc_ptr->toc);
-       regs->gpr[3] = signr;
-       regs->result = 0;
-       if (ka->sa.sa_flags & SA_SIGINFO) {
-               err |= get_user(regs->gpr[4], (unsigned long __user *)&frame->pinfo);
-               err |= get_user(regs->gpr[5], (unsigned long __user *)&frame->puc);
-               regs->gpr[6] = (unsigned long) frame;
-       } else {
-               regs->gpr[4] = (unsigned long)&frame->uc.uc_mcontext;
-       }
-       if (err)
-               goto badframe;
-
-       if (test_thread_flag(TIF_SINGLESTEP))
-               ptrace_notify(SIGTRAP);
-
-       return 1;
-
-badframe:
-#if DEBUG_SIG
-       printk("badframe in setup_rt_frame, regs=%p frame=%p newsp=%lx\n",
-              regs, frame, newsp);
-#endif
-       force_sigsegv(signr, current);
-       return 0;
-}
-
-
-/*
- * OK, we're invoking a handler
- */
-static int handle_signal(unsigned long sig, struct k_sigaction *ka,
-                        siginfo_t *info, sigset_t *oldset, struct pt_regs *regs)
-{
-       int ret;
-
-       /* Set up Signal Frame */
-       ret = setup_rt_frame(sig, ka, info, oldset, regs);
-
-       if (ret) {
-               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;
-}
-
-static inline void syscall_restart(struct pt_regs *regs, struct k_sigaction *ka)
-{
-       switch ((int)regs->result) {
-       case -ERESTART_RESTARTBLOCK:
-       case -ERESTARTNOHAND:
-               /* ERESTARTNOHAND means that the syscall should only be
-                * restarted if there was no handler for the signal, and since
-                * we only get here if there is a handler, we dont restart.
-                */
-               regs->result = -EINTR;
-               break;
-       case -ERESTARTSYS:
-               /* ERESTARTSYS means to restart the syscall if there is no
-                * handler or the handler was registered with SA_RESTART
-                */
-               if (!(ka->sa.sa_flags & SA_RESTART)) {
-                       regs->result = -EINTR;
-                       break;
-               }
-               /* fallthrough */
-       case -ERESTARTNOINTR:
-               /* ERESTARTNOINTR means that the syscall should be
-                * called again after the signal handler returns.
-                */
-               regs->gpr[3] = regs->orig_gpr3;
-               regs->nip -= 4;
-               regs->result = 0;
-               break;
-       }
-}
-
-/*
- * 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;
-       int signr;
-       struct k_sigaction ka;
-
-       /*
-        * If the current thread is 32 bit - invoke the
-        * 32 bit signal handling code
-        */
-       if (test_thread_flag(TIF_32BIT))
-               return do_signal32(oldset, regs);
-
-       if (!oldset)
-               oldset = &current->blocked;
-
-       signr = get_signal_to_deliver(&info, &ka, regs, NULL);
-       if (signr > 0) {
-               /* Whee!  Actually deliver the signal.  */
-               if (TRAP(regs) == 0x0C00)
-                       syscall_restart(regs, &ka);
-
-               /*
-                * Reenable the DABR before delivering the signal to
-                * user space. The DABR will have been cleared if it
-                * triggered inside the kernel.
-                */
-               if (current->thread.dabr)
-                       set_dabr(current->thread.dabr);
-
-               return handle_signal(signr, &ka, &info, oldset, regs);
-       }
-
-       if (TRAP(regs) == 0x0C00) {     /* System Call! */
-               if ((int)regs->result == -ERESTARTNOHAND ||
-                   (int)regs->result == -ERESTARTSYS ||
-                   (int)regs->result == -ERESTARTNOINTR) {
-                       regs->gpr[3] = regs->orig_gpr3;
-                       regs->nip -= 4; /* Back up & retry system call */
-                       regs->result = 0;
-               } else if ((int)regs->result == -ERESTART_RESTARTBLOCK) {
-                       regs->gpr[0] = __NR_restart_syscall;
-                       regs->nip -= 4;
-                       regs->result = 0;
-               }
-       }
-
-       return 0;
-}
-EXPORT_SYMBOL(do_signal);
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