1 files changed, 382 insertions, 0 deletions

diff --git a/arch/um/sys-i386/signal.c b/arch/um/sys-i386/signal.c
new file mode 100644
index 000000000000..76ba87254b25
--- /dev/null
+++ b/arch/um/sys-i386/signal.c
@@ -0,0 +1,382 @@
+/*
+ * Copyright (C) 2004 Jeff Dike (jdike@addtoit.com)
+ * Licensed under the GPL
+ */
+
+#include "linux/signal.h"
+#include "linux/ptrace.h"
+#include "asm/current.h"
+#include "asm/ucontext.h"
+#include "asm/uaccess.h"
+#include "asm/unistd.h"
+#include "frame_kern.h"
+#include "signal_user.h"
+#include "sigcontext.h"
+#include "registers.h"
+#include "mode.h"
+
+#ifdef CONFIG_MODE_SKAS
+
+#include "skas.h"
+
+static int copy_sc_from_user_skas(struct pt_regs *regs,
+                                  struct sigcontext *from)
+{
+        struct sigcontext sc;
+        unsigned long fpregs[HOST_FP_SIZE];
+        int err;
+
+        err = copy_from_user(&sc, from, sizeof(sc));
+        err |= copy_from_user(fpregs, sc.fpstate, sizeof(fpregs));
+        if(err)
+                return(err);
+
+        REGS_GS(regs->regs.skas.regs) = sc.gs;
+        REGS_FS(regs->regs.skas.regs) = sc.fs;
+        REGS_ES(regs->regs.skas.regs) = sc.es;
+        REGS_DS(regs->regs.skas.regs) = sc.ds;
+        REGS_EDI(regs->regs.skas.regs) = sc.edi;
+        REGS_ESI(regs->regs.skas.regs) = sc.esi;
+        REGS_EBP(regs->regs.skas.regs) = sc.ebp;
+        REGS_SP(regs->regs.skas.regs) = sc.esp;
+        REGS_EBX(regs->regs.skas.regs) = sc.ebx;
+        REGS_EDX(regs->regs.skas.regs) = sc.edx;
+        REGS_ECX(regs->regs.skas.regs) = sc.ecx;
+        REGS_EAX(regs->regs.skas.regs) = sc.eax;
+        REGS_IP(regs->regs.skas.regs) = sc.eip;
+        REGS_CS(regs->regs.skas.regs) = sc.cs;
+        REGS_EFLAGS(regs->regs.skas.regs) = sc.eflags;
+        REGS_SS(regs->regs.skas.regs) = sc.ss;
+        regs->regs.skas.fault_addr = sc.cr2;
+        regs->regs.skas.fault_type = FAULT_WRITE(sc.err);
+        regs->regs.skas.trap_type = sc.trapno;
+
+        err = restore_fp_registers(userspace_pid[0], fpregs);
+        if(err < 0){
+                printk("copy_sc_from_user_skas - PTRACE_SETFPREGS failed, "
+                       "errno = %d\n", err);
+                return(1);
+        }
+
+        return(0);
+}
+
+int copy_sc_to_user_skas(struct sigcontext *to, struct _fpstate *to_fp,
+                         struct pt_regs *regs, unsigned long fault_addr,
+                         int fault_type)
+{
+        struct sigcontext sc;
+        unsigned long fpregs[HOST_FP_SIZE];
+        int err;
+
+        sc.gs = REGS_GS(regs->regs.skas.regs);
+        sc.fs = REGS_FS(regs->regs.skas.regs);
+        sc.es = REGS_ES(regs->regs.skas.regs);
+        sc.ds = REGS_DS(regs->regs.skas.regs);
+        sc.edi = REGS_EDI(regs->regs.skas.regs);
+        sc.esi = REGS_ESI(regs->regs.skas.regs);
+        sc.ebp = REGS_EBP(regs->regs.skas.regs);
+        sc.esp = REGS_SP(regs->regs.skas.regs);
+        sc.ebx = REGS_EBX(regs->regs.skas.regs);
+        sc.edx = REGS_EDX(regs->regs.skas.regs);
+        sc.ecx = REGS_ECX(regs->regs.skas.regs);
+        sc.eax = REGS_EAX(regs->regs.skas.regs);
+        sc.eip = REGS_IP(regs->regs.skas.regs);
+        sc.cs = REGS_CS(regs->regs.skas.regs);
+        sc.eflags = REGS_EFLAGS(regs->regs.skas.regs);
+        sc.esp_at_signal = regs->regs.skas.regs[UESP];
+        sc.ss = regs->regs.skas.regs[SS];
+        sc.cr2 = fault_addr;
+        sc.err = TO_SC_ERR(fault_type);
+        sc.trapno = regs->regs.skas.trap_type;
+
+        err = save_fp_registers(userspace_pid[0], fpregs);
+        if(err < 0){
+                printk("copy_sc_to_user_skas - PTRACE_GETFPREGS failed, "
+                       "errno = %d\n", err);
+                return(1);
+        }
+        to_fp = (to_fp ? to_fp : (struct _fpstate *) (to + 1));
+        sc.fpstate = to_fp;
+
+        if(err)
+                return(err);
+
+        return(copy_to_user(to, &sc, sizeof(sc)) ||
+               copy_to_user(to_fp, fpregs, sizeof(fpregs)));
+}
+#endif
+
+#ifdef CONFIG_MODE_TT
+
+/* These copy a sigcontext to/from userspace.  They copy the fpstate pointer,
+ * blowing away the old, good one.  So, that value is saved, and then restored
+ * after the sigcontext copy.  In copy_from, the variable holding the saved
+ * fpstate pointer, and the sigcontext that it should be restored to are both
+ * in the kernel, so we can just restore using an assignment.  In copy_to, the
+ * saved pointer is in the kernel, but the sigcontext is in userspace, so we
+ * copy_to_user it.
+ */
+int copy_sc_from_user_tt(struct sigcontext *to, struct sigcontext *from,
+                         int fpsize)
+{
+        struct _fpstate *to_fp, *from_fp;
+        unsigned long sigs;
+        int err;
+
+        to_fp = to->fpstate;
+        from_fp = from->fpstate;
+        sigs = to->oldmask;
+        err = copy_from_user(to, from, sizeof(*to));
+        to->oldmask = sigs;
+        to->fpstate = to_fp;
+        if(to_fp != NULL)
+                err |= copy_from_user(to_fp, from_fp, fpsize);
+        return(err);
+}
+
+int copy_sc_to_user_tt(struct sigcontext *to, struct _fpstate *fp,
+                       struct sigcontext *from, int fpsize)
+{
+        struct _fpstate *to_fp, *from_fp;
+        int err;
+
+        to_fp = (fp ? fp : (struct _fpstate *) (to + 1));
+        from_fp = from->fpstate;
+        err = copy_to_user(to, from, sizeof(*to));
+        if(from_fp != NULL){
+                err |= copy_to_user(&to->fpstate, &to_fp, sizeof(to->fpstate));
+                err |= copy_to_user(to_fp, from_fp, fpsize);
+        }
+        return(err);
+}
+#endif
+
+static int copy_sc_from_user(struct pt_regs *to, void __user *from)
+{
+        int ret;
+
+        ret = CHOOSE_MODE(copy_sc_from_user_tt(UPT_SC(&to->regs), from,
+                                               sizeof(struct _fpstate)),
+                          copy_sc_from_user_skas(to, from));
+        return(ret);
+}
+
+static int copy_sc_to_user(struct sigcontext *to, struct _fpstate *fp,
+                           struct pt_regs *from)
+{
+        return(CHOOSE_MODE(copy_sc_to_user_tt(to, fp, UPT_SC(&from->regs),
+                                              sizeof(*fp)),
+                           copy_sc_to_user_skas(to, fp, from,
+                                                current->thread.cr2,
+                                                current->thread.err)));
+}
+
+static int copy_ucontext_to_user(struct ucontext *uc, struct _fpstate *fp,
+                                 sigset_t *set, unsigned long sp)
+{
+        int err = 0;
+
+        err |= put_user(current->sas_ss_sp, &uc->uc_stack.ss_sp);
+        err |= put_user(sas_ss_flags(sp), &uc->uc_stack.ss_flags);
+        err |= put_user(current->sas_ss_size, &uc->uc_stack.ss_size);
+        err |= copy_sc_to_user(&uc->uc_mcontext, fp, &current->thread.regs);
+        err |= copy_to_user(&uc->uc_sigmask, set, sizeof(*set));
+        return(err);
+}
+
+struct sigframe
+{
+        char *pretcode;
+        int sig;
+        struct sigcontext sc;
+        struct _fpstate fpstate;
+        unsigned long extramask[_NSIG_WORDS-1];
+        char retcode[8];
+};
+
+struct rt_sigframe
+{
+        char *pretcode;
+        int sig;
+        struct siginfo *pinfo;
+        void *puc;
+        struct siginfo info;
+        struct ucontext uc;
+        struct _fpstate fpstate;
+        char retcode[8];
+};
+
+int setup_signal_stack_sc(unsigned long stack_top, int sig,
+                          struct k_sigaction *ka, struct pt_regs *regs,
+                          sigset_t *mask)
+{
+        struct sigframe __user *frame;
+        void *restorer;
+        int err = 0;
+
+        stack_top &= -8UL;
+        frame = (struct sigframe *) stack_top - 1;
+        if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
+                return 1;
+
+        restorer = (void *) frame->retcode;
+        if(ka->sa.sa_flags & SA_RESTORER)
+                restorer = ka->sa.sa_restorer;
+
+        err |= __put_user(restorer, &frame->pretcode);
+        err |= __put_user(sig, &frame->sig);
+        err |= copy_sc_to_user(&frame->sc, NULL, regs);
+        err |= __put_user(mask->sig[0], &frame->sc.oldmask);
+        if (_NSIG_WORDS > 1)
+                err |= __copy_to_user(&frame->extramask, &mask->sig[1],
+                                      sizeof(frame->extramask));
+
+        /*
+         * This is popl %eax ; movl $,%eax ; int $0x80
+         *
+         * WE DO NOT USE IT ANY MORE! It's only left here for historical
+         * reasons and because gdb uses it as a signature to notice
+         * signal handler stack frames.
+         */
+        err |= __put_user(0xb858, (short __user *)(frame->retcode+0));
+        err |= __put_user(__NR_sigreturn, (int __user *)(frame->retcode+2));
+        err |= __put_user(0x80cd, (short __user *)(frame->retcode+6));
+
+        if(err)
+                return(err);
+
+        PT_REGS_SP(regs) = (unsigned long) frame;
+        PT_REGS_IP(regs) = (unsigned long) ka->sa.sa_handler;
+        PT_REGS_EAX(regs) = (unsigned long) sig;
+        PT_REGS_EDX(regs) = (unsigned long) 0;
+        PT_REGS_ECX(regs) = (unsigned long) 0;
+
+        if ((current->ptrace & PT_DTRACE) && (current->ptrace & PT_PTRACED))
+                ptrace_notify(SIGTRAP);
+        return(0);
+}
+
+int setup_signal_stack_si(unsigned long stack_top, int sig,
+                          struct k_sigaction *ka, struct pt_regs *regs,
+                          siginfo_t *info, sigset_t *mask)
+{
+        struct rt_sigframe __user *frame;
+        void *restorer;
+        int err = 0;
+
+        stack_top &= -8UL;
+        frame = (struct rt_sigframe *) stack_top - 1;
+        if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
+                return 1;
+
+        restorer = (void *) frame->retcode;
+        if(ka->sa.sa_flags & SA_RESTORER)
+                restorer = ka->sa.sa_restorer;
+
+        err |= __put_user(restorer, &frame->pretcode);
+        err |= __put_user(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);
+        err |= copy_ucontext_to_user(&frame->uc, &frame->fpstate, mask,
+                                     PT_REGS_SP(regs));
+
+        /*
+         * This is movl $,%eax ; int $0x80
+         *
+         * WE DO NOT USE IT ANY MORE! It's only left here for historical
+         * reasons and because gdb uses it as a signature to notice
+         * signal handler stack frames.
+         */
+        err |= __put_user(0xb8, (char __user *)(frame->retcode+0));
+        err |= __put_user(__NR_rt_sigreturn, (int __user *)(frame->retcode+1));
+        err |= __put_user(0x80cd, (short __user *)(frame->retcode+5));
+
+        if(err)
+                return(err);
+
+        PT_REGS_SP(regs) = (unsigned long) frame;
+        PT_REGS_IP(regs) = (unsigned long) ka->sa.sa_handler;
+        PT_REGS_EAX(regs) = (unsigned long) sig;
+        PT_REGS_EDX(regs) = (unsigned long) &frame->info;
+        PT_REGS_ECX(regs) = (unsigned long) &frame->uc;
+
+        if ((current->ptrace & PT_DTRACE) && (current->ptrace & PT_PTRACED))
+                ptrace_notify(SIGTRAP);
+        return(0);
+}
+
+long sys_sigreturn(struct pt_regs regs)
+{
+        unsigned long sp = PT_REGS_SP(&current->thread.regs);
+        struct sigframe __user *frame = (struct sigframe *)(sp - 8);
+        sigset_t set;
+        struct sigcontext __user *sc = &frame->sc;
+        unsigned long __user *oldmask = &sc->oldmask;
+        unsigned long __user *extramask = frame->extramask;
+        int sig_size = (_NSIG_WORDS - 1) * sizeof(unsigned long);
+
+        if(copy_from_user(&set.sig[0], oldmask, sizeof(&set.sig[0])) ||
+           copy_from_user(&set.sig[1], extramask, sig_size))
+                goto segfault;
+
+        sigdelsetmask(&set, ~_BLOCKABLE);
+
+        spin_lock_irq(&current->sighand->siglock);
+        current->blocked = set;
+        recalc_sigpending();
+        spin_unlock_irq(&current->sighand->siglock);
+
+        if(copy_sc_from_user(&current->thread.regs, sc))
+                goto segfault;
+
+        /* Avoid ERESTART handling */
+        PT_REGS_SYSCALL_NR(&current->thread.regs) = -1;
+        return(PT_REGS_SYSCALL_RET(&current->thread.regs));
+
+ segfault:
+        force_sig(SIGSEGV, current);
+        return 0;
+}
+
+long sys_rt_sigreturn(struct pt_regs regs)
+{
+        unsigned long __user sp = PT_REGS_SP(&current->thread.regs);
+        struct rt_sigframe __user *frame = (struct rt_sigframe *) (sp - 4);
+        sigset_t set;
+        struct ucontext __user *uc = &frame->uc;
+        int sig_size = _NSIG_WORDS * sizeof(unsigned long);
+
+        if(copy_from_user(&set, &uc->uc_sigmask, sig_size))
+                goto segfault;
+
+        sigdelsetmask(&set, ~_BLOCKABLE);
+
+        spin_lock_irq(&current->sighand->siglock);
+        current->blocked = set;
+        recalc_sigpending();
+        spin_unlock_irq(&current->sighand->siglock);
+
+        if(copy_sc_from_user(&current->thread.regs, &uc->uc_mcontext))
+                goto segfault;
+
+        /* Avoid ERESTART handling */
+        PT_REGS_SYSCALL_NR(&current->thread.regs) = -1;
+        return(PT_REGS_SYSCALL_RET(&current->thread.regs));
+
+ segfault:
+        force_sig(SIGSEGV, current);
+        return 0;
+}
+
+/*
+ * Overrides for Emacs so that we follow Linus's tabbing style.
+ * Emacs will notice this stuff at the end of the file and automatically
+ * adjust the settings for this buffer only.  This must remain at the end
+ * of the file.
+ * ---------------------------------------------------------------------------
+ * Local variables:
+ * c-file-style: "linux"
+ * End:
+ */