Initial import

1 files changed, 547 insertions, 0 deletions

diff --git a/arch/sparc/kernel/signal_64.c b/arch/sparc/kernel/signal_64.c
new file mode 100644
index 000000000..d88beff47
--- /dev/null
+++ b/arch/sparc/kernel/signal_64.c
@@ -0,0 +1,547 @@
+/*
+ *  arch/sparc64/kernel/signal.c
+ *
+ *  Copyright (C) 1991, 1992  Linus Torvalds
+ *  Copyright (C) 1995, 2008 David S. Miller (davem@davemloft.net)
+ *  Copyright (C) 1996 Miguel de Icaza (miguel@nuclecu.unam.mx)
+ *  Copyright (C) 1997 Eddie C. Dost   (ecd@skynet.be)
+ *  Copyright (C) 1997,1998 Jakub Jelinek   (jj@sunsite.mff.cuni.cz)
+ */
+
+#ifdef CONFIG_COMPAT
+#include <linux/compat.h>	/* for compat_old_sigset_t */
+#endif
+#include <linux/sched.h>
+#include <linux/kernel.h>
+#include <linux/signal.h>
+#include <linux/errno.h>
+#include <linux/wait.h>
+#include <linux/ptrace.h>
+#include <linux/tracehook.h>
+#include <linux/unistd.h>
+#include <linux/mm.h>
+#include <linux/tty.h>
+#include <linux/binfmts.h>
+#include <linux/bitops.h>
+#include <linux/context_tracking.h>
+
+#include <asm/uaccess.h>
+#include <asm/ptrace.h>
+#include <asm/pgtable.h>
+#include <asm/fpumacro.h>
+#include <asm/uctx.h>
+#include <asm/siginfo.h>
+#include <asm/visasm.h>
+#include <asm/switch_to.h>
+#include <asm/cacheflush.h>
+
+#include "sigutil.h"
+#include "systbls.h"
+#include "kernel.h"
+#include "entry.h"
+
+/* {set, get}context() needed for 64-bit SparcLinux userland. */
+asmlinkage void sparc64_set_context(struct pt_regs *regs)
+{
+	struct ucontext __user *ucp = (struct ucontext __user *)
+		regs->u_regs[UREG_I0];
+	enum ctx_state prev_state = exception_enter();
+	mc_gregset_t __user *grp;
+	unsigned long pc, npc, tstate;
+	unsigned long fp, i7;
+	unsigned char fenab;
+	int err;
+
+	flush_user_windows();
+	if (get_thread_wsaved()					||
+	    (((unsigned long)ucp) & (sizeof(unsigned long)-1))	||
+	    (!__access_ok(ucp, sizeof(*ucp))))
+		goto do_sigsegv;
+	grp  = &ucp->uc_mcontext.mc_gregs;
+	err  = __get_user(pc, &((*grp)[MC_PC]));
+	err |= __get_user(npc, &((*grp)[MC_NPC]));
+	if (err || ((pc | npc) & 3))
+		goto do_sigsegv;
+	if (regs->u_regs[UREG_I1]) {
+		sigset_t set;
+
+		if (_NSIG_WORDS == 1) {
+			if (__get_user(set.sig[0], &ucp->uc_sigmask.sig[0]))
+				goto do_sigsegv;
+		} else {
+			if (__copy_from_user(&set, &ucp->uc_sigmask, sizeof(sigset_t)))
+				goto do_sigsegv;
+		}
+		set_current_blocked(&set);
+	}
+	if (test_thread_flag(TIF_32BIT)) {
+		pc &= 0xffffffff;
+		npc &= 0xffffffff;
+	}
+	regs->tpc = pc;
+	regs->tnpc = npc;
+	err |= __get_user(regs->y, &((*grp)[MC_Y]));
+	err |= __get_user(tstate, &((*grp)[MC_TSTATE]));
+	regs->tstate &= ~(TSTATE_ASI | TSTATE_ICC | TSTATE_XCC);
+	regs->tstate |= (tstate & (TSTATE_ASI | TSTATE_ICC | TSTATE_XCC));
+	err |= __get_user(regs->u_regs[UREG_G1], (&(*grp)[MC_G1]));
+	err |= __get_user(regs->u_regs[UREG_G2], (&(*grp)[MC_G2]));
+	err |= __get_user(regs->u_regs[UREG_G3], (&(*grp)[MC_G3]));
+	err |= __get_user(regs->u_regs[UREG_G4], (&(*grp)[MC_G4]));
+	err |= __get_user(regs->u_regs[UREG_G5], (&(*grp)[MC_G5]));
+	err |= __get_user(regs->u_regs[UREG_G6], (&(*grp)[MC_G6]));
+
+	/* Skip %g7 as that's the thread register in userspace.  */
+
+	err |= __get_user(regs->u_regs[UREG_I0], (&(*grp)[MC_O0]));
+	err |= __get_user(regs->u_regs[UREG_I1], (&(*grp)[MC_O1]));
+	err |= __get_user(regs->u_regs[UREG_I2], (&(*grp)[MC_O2]));
+	err |= __get_user(regs->u_regs[UREG_I3], (&(*grp)[MC_O3]));
+	err |= __get_user(regs->u_regs[UREG_I4], (&(*grp)[MC_O4]));
+	err |= __get_user(regs->u_regs[UREG_I5], (&(*grp)[MC_O5]));
+	err |= __get_user(regs->u_regs[UREG_I6], (&(*grp)[MC_O6]));
+	err |= __get_user(regs->u_regs[UREG_I7], (&(*grp)[MC_O7]));
+
+	err |= __get_user(fp, &(ucp->uc_mcontext.mc_fp));
+	err |= __get_user(i7, &(ucp->uc_mcontext.mc_i7));
+	err |= __put_user(fp,
+	      (&(((struct reg_window __user *)(STACK_BIAS+regs->u_regs[UREG_I6]))->ins[6])));
+	err |= __put_user(i7,
+	      (&(((struct reg_window __user *)(STACK_BIAS+regs->u_regs[UREG_I6]))->ins[7])));
+
+	err |= __get_user(fenab, &(ucp->uc_mcontext.mc_fpregs.mcfpu_enab));
+	if (fenab) {
+		unsigned long *fpregs = current_thread_info()->fpregs;
+		unsigned long fprs;
+		
+		fprs_write(0);
+		err |= __get_user(fprs, &(ucp->uc_mcontext.mc_fpregs.mcfpu_fprs));
+		if (fprs & FPRS_DL)
+			err |= copy_from_user(fpregs,
+					      &(ucp->uc_mcontext.mc_fpregs.mcfpu_fregs),
+					      (sizeof(unsigned int) * 32));
+		if (fprs & FPRS_DU)
+			err |= copy_from_user(fpregs+16,
+			 ((unsigned long __user *)&(ucp->uc_mcontext.mc_fpregs.mcfpu_fregs))+16,
+			 (sizeof(unsigned int) * 32));
+		err |= __get_user(current_thread_info()->xfsr[0],
+				  &(ucp->uc_mcontext.mc_fpregs.mcfpu_fsr));
+		err |= __get_user(current_thread_info()->gsr[0],
+				  &(ucp->uc_mcontext.mc_fpregs.mcfpu_gsr));
+		regs->tstate &= ~TSTATE_PEF;
+	}
+	if (err)
+		goto do_sigsegv;
+out:
+	exception_exit(prev_state);
+	return;
+do_sigsegv:
+	force_sig(SIGSEGV, current);
+	goto out;
+}
+
+asmlinkage void sparc64_get_context(struct pt_regs *regs)
+{
+	struct ucontext __user *ucp = (struct ucontext __user *)
+		regs->u_regs[UREG_I0];
+	enum ctx_state prev_state = exception_enter();
+	mc_gregset_t __user *grp;
+	mcontext_t __user *mcp;
+	unsigned long fp, i7;
+	unsigned char fenab;
+	int err;
+
+	synchronize_user_stack();
+	if (get_thread_wsaved() || clear_user(ucp, sizeof(*ucp)))
+		goto do_sigsegv;
+
+#if 1
+	fenab = 0; /* IMO get_context is like any other system call, thus modifies FPU state -jj */
+#else
+	fenab = (current_thread_info()->fpsaved[0] & FPRS_FEF);
+#endif
+		
+	mcp = &ucp->uc_mcontext;
+	grp = &mcp->mc_gregs;
+
+	/* Skip over the trap instruction, first. */
+	if (test_thread_flag(TIF_32BIT)) {
+		regs->tpc   = (regs->tnpc & 0xffffffff);
+		regs->tnpc  = (regs->tnpc + 4) & 0xffffffff;
+	} else {
+		regs->tpc   = regs->tnpc;
+		regs->tnpc += 4;
+	}
+	err = 0;
+	if (_NSIG_WORDS == 1)
+		err |= __put_user(current->blocked.sig[0],
+				  (unsigned long __user *)&ucp->uc_sigmask);
+	else
+		err |= __copy_to_user(&ucp->uc_sigmask, &current->blocked,
+				      sizeof(sigset_t));
+
+	err |= __put_user(regs->tstate, &((*grp)[MC_TSTATE]));
+	err |= __put_user(regs->tpc, &((*grp)[MC_PC]));
+	err |= __put_user(regs->tnpc, &((*grp)[MC_NPC]));
+	err |= __put_user(regs->y, &((*grp)[MC_Y]));
+	err |= __put_user(regs->u_regs[UREG_G1], &((*grp)[MC_G1]));
+	err |= __put_user(regs->u_regs[UREG_G2], &((*grp)[MC_G2]));
+	err |= __put_user(regs->u_regs[UREG_G3], &((*grp)[MC_G3]));
+	err |= __put_user(regs->u_regs[UREG_G4], &((*grp)[MC_G4]));
+	err |= __put_user(regs->u_regs[UREG_G5], &((*grp)[MC_G5]));
+	err |= __put_user(regs->u_regs[UREG_G6], &((*grp)[MC_G6]));
+	err |= __put_user(regs->u_regs[UREG_G7], &((*grp)[MC_G7]));
+	err |= __put_user(regs->u_regs[UREG_I0], &((*grp)[MC_O0]));
+	err |= __put_user(regs->u_regs[UREG_I1], &((*grp)[MC_O1]));
+	err |= __put_user(regs->u_regs[UREG_I2], &((*grp)[MC_O2]));
+	err |= __put_user(regs->u_regs[UREG_I3], &((*grp)[MC_O3]));
+	err |= __put_user(regs->u_regs[UREG_I4], &((*grp)[MC_O4]));
+	err |= __put_user(regs->u_regs[UREG_I5], &((*grp)[MC_O5]));
+	err |= __put_user(regs->u_regs[UREG_I6], &((*grp)[MC_O6]));
+	err |= __put_user(regs->u_regs[UREG_I7], &((*grp)[MC_O7]));
+
+	err |= __get_user(fp,
+		 (&(((struct reg_window __user *)(STACK_BIAS+regs->u_regs[UREG_I6]))->ins[6])));
+	err |= __get_user(i7,
+		 (&(((struct reg_window __user *)(STACK_BIAS+regs->u_regs[UREG_I6]))->ins[7])));
+	err |= __put_user(fp, &(mcp->mc_fp));
+	err |= __put_user(i7, &(mcp->mc_i7));
+
+	err |= __put_user(fenab, &(mcp->mc_fpregs.mcfpu_enab));
+	if (fenab) {
+		unsigned long *fpregs = current_thread_info()->fpregs;
+		unsigned long fprs;
+		
+		fprs = current_thread_info()->fpsaved[0];
+		if (fprs & FPRS_DL)
+			err |= copy_to_user(&(mcp->mc_fpregs.mcfpu_fregs), fpregs,
+					    (sizeof(unsigned int) * 32));
+		if (fprs & FPRS_DU)
+			err |= copy_to_user(
+                          ((unsigned long __user *)&(mcp->mc_fpregs.mcfpu_fregs))+16, fpregs+16,
+			  (sizeof(unsigned int) * 32));
+		err |= __put_user(current_thread_info()->xfsr[0], &(mcp->mc_fpregs.mcfpu_fsr));
+		err |= __put_user(current_thread_info()->gsr[0], &(mcp->mc_fpregs.mcfpu_gsr));
+		err |= __put_user(fprs, &(mcp->mc_fpregs.mcfpu_fprs));
+	}
+	if (err)
+		goto do_sigsegv;
+out:
+	exception_exit(prev_state);
+	return;
+do_sigsegv:
+	force_sig(SIGSEGV, current);
+	goto out;
+}
+
+struct rt_signal_frame {
+	struct sparc_stackf	ss;
+	siginfo_t		info;
+	struct pt_regs		regs;
+	__siginfo_fpu_t __user	*fpu_save;
+	stack_t			stack;
+	sigset_t		mask;
+	__siginfo_rwin_t	*rwin_save;
+};
+
+void do_rt_sigreturn(struct pt_regs *regs)
+{
+	struct rt_signal_frame __user *sf;
+	unsigned long tpc, tnpc, tstate;
+	__siginfo_fpu_t __user *fpu_save;
+	__siginfo_rwin_t __user *rwin_save;
+	sigset_t set;
+	int err;
+
+	/* Always make any pending restarted system calls return -EINTR */
+	current->restart_block.fn = do_no_restart_syscall;
+
+	synchronize_user_stack ();
+	sf = (struct rt_signal_frame __user *)
+		(regs->u_regs [UREG_FP] + STACK_BIAS);
+
+	/* 1. Make sure we are not getting garbage from the user */
+	if (((unsigned long) sf) & 3)
+		goto segv;
+
+	err = get_user(tpc, &sf->regs.tpc);
+	err |= __get_user(tnpc, &sf->regs.tnpc);
+	if (test_thread_flag(TIF_32BIT)) {
+		tpc &= 0xffffffff;
+		tnpc &= 0xffffffff;
+	}
+	err |= ((tpc | tnpc) & 3);
+
+	/* 2. Restore the state */
+	err |= __get_user(regs->y, &sf->regs.y);
+	err |= __get_user(tstate, &sf->regs.tstate);
+	err |= copy_from_user(regs->u_regs, sf->regs.u_regs, sizeof(regs->u_regs));
+
+	/* User can only change condition codes and %asi in %tstate. */
+	regs->tstate &= ~(TSTATE_ASI | TSTATE_ICC | TSTATE_XCC);
+	regs->tstate |= (tstate & (TSTATE_ASI | TSTATE_ICC | TSTATE_XCC));
+
+	err |= __get_user(fpu_save, &sf->fpu_save);
+	if (!err && fpu_save)
+		err |= restore_fpu_state(regs, fpu_save);
+
+	err |= __copy_from_user(&set, &sf->mask, sizeof(sigset_t));
+	err |= restore_altstack(&sf->stack);
+	if (err)
+		goto segv;
+
+	err |= __get_user(rwin_save, &sf->rwin_save);
+	if (!err && rwin_save) {
+		if (restore_rwin_state(rwin_save))
+			goto segv;
+	}
+
+	regs->tpc = tpc;
+	regs->tnpc = tnpc;
+
+	/* Prevent syscall restart.  */
+	pt_regs_clear_syscall(regs);
+
+	set_current_blocked(&set);
+	return;
+segv:
+	force_sig(SIGSEGV, current);
+}
+
+/* Checks if the fp is valid */
+static int invalid_frame_pointer(void __user *fp)
+{
+	if (((unsigned long) fp) & 15)
+		return 1;
+	return 0;
+}
+
+static inline void __user *get_sigframe(struct ksignal *ksig, struct pt_regs *regs, unsigned long framesize)
+{
+	unsigned long sp = regs->u_regs[UREG_FP] + STACK_BIAS;
+
+	/*
+	 * If we are on the alternate signal stack and would overflow it, don't.
+	 * Return an always-bogus address instead so we will die with SIGSEGV.
+	 */
+	if (on_sig_stack(sp) && !likely(on_sig_stack(sp - framesize)))
+		return (void __user *) -1L;
+
+	/* This is the X/Open sanctioned signal stack switching.  */
+	sp = sigsp(sp, ksig) - framesize;
+
+	/* Always align the stack frame.  This handles two cases.  First,
+	 * sigaltstack need not be mindful of platform specific stack
+	 * alignment.  Second, if we took this signal because the stack
+	 * is not aligned properly, we'd like to take the signal cleanly
+	 * and report that.
+	 */
+	sp &= ~15UL;
+
+	return (void __user *) sp;
+}
+
+static inline int
+setup_rt_frame(struct ksignal *ksig, struct pt_regs *regs)
+{
+	struct rt_signal_frame __user *sf;
+	int wsaved, err, sf_size;
+	void __user *tail;
+
+	/* 1. Make sure everything is clean */
+	synchronize_user_stack();
+	save_and_clear_fpu();
+	
+	wsaved = get_thread_wsaved();
+
+	sf_size = sizeof(struct rt_signal_frame);
+	if (current_thread_info()->fpsaved[0] & FPRS_FEF)
+		sf_size += sizeof(__siginfo_fpu_t);
+	if (wsaved)
+		sf_size += sizeof(__siginfo_rwin_t);
+	sf = (struct rt_signal_frame __user *)
+		get_sigframe(ksig, regs, sf_size);
+
+	if (invalid_frame_pointer (sf)) {
+		do_exit(SIGILL);	/* won't return, actually */
+		return -EINVAL;
+	}
+
+	tail = (sf + 1);
+
+	/* 2. Save the current process state */
+	err = copy_to_user(&sf->regs, regs, sizeof (*regs));
+
+	if (current_thread_info()->fpsaved[0] & FPRS_FEF) {
+		__siginfo_fpu_t __user *fpu_save = tail;
+		tail += sizeof(__siginfo_fpu_t);
+		err |= save_fpu_state(regs, fpu_save);
+		err |= __put_user((u64)fpu_save, &sf->fpu_save);
+	} else {
+		err |= __put_user(0, &sf->fpu_save);
+	}
+	if (wsaved) {
+		__siginfo_rwin_t __user *rwin_save = tail;
+		tail += sizeof(__siginfo_rwin_t);
+		err |= save_rwin_state(wsaved, rwin_save);
+		err |= __put_user((u64)rwin_save, &sf->rwin_save);
+		set_thread_wsaved(0);
+	} else {
+		err |= __put_user(0, &sf->rwin_save);
+	}
+	
+	/* Setup sigaltstack */
+	err |= __save_altstack(&sf->stack, regs->u_regs[UREG_FP]);
+
+	err |= copy_to_user(&sf->mask, sigmask_to_save(), sizeof(sigset_t));
+
+	if (!wsaved) {
+		err |= copy_in_user((u64 __user *)sf,
+				    (u64 __user *)(regs->u_regs[UREG_FP] +
+						   STACK_BIAS),
+				    sizeof(struct reg_window));
+	} else {
+		struct reg_window *rp;
+
+		rp = &current_thread_info()->reg_window[wsaved - 1];
+		err |= copy_to_user(sf, rp, sizeof(struct reg_window));
+	}
+	if (ksig->ka.sa.sa_flags & SA_SIGINFO)
+		err |= copy_siginfo_to_user(&sf->info, &ksig->info);
+	else {
+		err |= __put_user(ksig->sig, &sf->info.si_signo);
+		err |= __put_user(SI_NOINFO, &sf->info.si_code);
+	}
+	if (err)
+		return err;
+	
+	/* 3. signal handler back-trampoline and parameters */
+	regs->u_regs[UREG_FP] = ((unsigned long) sf) - STACK_BIAS;
+	regs->u_regs[UREG_I0] = ksig->sig;
+	regs->u_regs[UREG_I1] = (unsigned long) &sf->info;
+
+	/* The sigcontext is passed in this way because of how it
+	 * is defined in GLIBC's /usr/include/bits/sigcontext.h
+	 * for sparc64.  It includes the 128 bytes of siginfo_t.
+	 */
+	regs->u_regs[UREG_I2] = (unsigned long) &sf->info;
+
+	/* 5. signal handler */
+	regs->tpc = (unsigned long) ksig->ka.sa.sa_handler;
+	regs->tnpc = (regs->tpc + 4);
+	if (test_thread_flag(TIF_32BIT)) {
+		regs->tpc &= 0xffffffff;
+		regs->tnpc &= 0xffffffff;
+	}
+	/* 4. return to kernel instructions */
+	regs->u_regs[UREG_I7] = (unsigned long)ksig->ka.ka_restorer;
+	return 0;
+}
+
+static inline void syscall_restart(unsigned long orig_i0, struct pt_regs *regs,
+				   struct sigaction *sa)
+{
+	switch (regs->u_regs[UREG_I0]) {
+	case ERESTART_RESTARTBLOCK:
+	case ERESTARTNOHAND:
+	no_system_call_restart:
+		regs->u_regs[UREG_I0] = EINTR;
+		regs->tstate |= (TSTATE_ICARRY|TSTATE_XCARRY);
+		break;
+	case ERESTARTSYS:
+		if (!(sa->sa_flags & SA_RESTART))
+			goto no_system_call_restart;
+		/* fallthrough */
+	case ERESTARTNOINTR:
+		regs->u_regs[UREG_I0] = orig_i0;
+		regs->tpc -= 4;
+		regs->tnpc -= 4;
+	}
+}
+
+/* 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.
+ */
+static void do_signal(struct pt_regs *regs, unsigned long orig_i0)
+{
+	struct ksignal ksig;
+	int restart_syscall;
+	bool has_handler;
+	
+	/* It's a lot of work and synchronization to add a new ptrace
+	 * register for GDB to save and restore in order to get
+	 * orig_i0 correct for syscall restarts when debugging.
+	 *
+	 * Although it should be the case that most of the global
+	 * registers are volatile across a system call, glibc already
+	 * depends upon that fact that we preserve them.  So we can't
+	 * just use any global register to save away the orig_i0 value.
+	 *
+	 * In particular %g2, %g3, %g4, and %g5 are all assumed to be
+	 * preserved across a system call trap by various pieces of
+	 * code in glibc.
+	 *
+	 * %g7 is used as the "thread register".   %g6 is not used in
+	 * any fixed manner.  %g6 is used as a scratch register and
+	 * a compiler temporary, but it's value is never used across
+	 * a system call.  Therefore %g6 is usable for orig_i0 storage.
+	 */
+	if (pt_regs_is_syscall(regs) &&
+	    (regs->tstate & (TSTATE_XCARRY | TSTATE_ICARRY)))
+		regs->u_regs[UREG_G6] = orig_i0;
+
+#ifdef CONFIG_COMPAT
+	if (test_thread_flag(TIF_32BIT)) {
+		do_signal32(regs);
+		return;
+	}
+#endif	
+
+	has_handler = get_signal(&ksig);
+
+	restart_syscall = 0;
+	if (pt_regs_is_syscall(regs) &&
+	    (regs->tstate & (TSTATE_XCARRY | TSTATE_ICARRY))) {
+		restart_syscall = 1;
+		orig_i0 = regs->u_regs[UREG_G6];
+	}
+
+	if (has_handler) {
+		if (restart_syscall)
+			syscall_restart(orig_i0, regs, &ksig.ka.sa);
+		signal_setup_done(setup_rt_frame(&ksig, regs), &ksig, 0);
+	} else {
+		if (restart_syscall) {
+			switch (regs->u_regs[UREG_I0]) {
+			case ERESTARTNOHAND:
+	     		case ERESTARTSYS:
+			case ERESTARTNOINTR:
+				/* replay the system call when we are done */
+				regs->u_regs[UREG_I0] = orig_i0;
+				regs->tpc -= 4;
+				regs->tnpc -= 4;
+				pt_regs_clear_syscall(regs);
+			case ERESTART_RESTARTBLOCK:
+				regs->u_regs[UREG_G1] = __NR_restart_syscall;
+				regs->tpc -= 4;
+				regs->tnpc -= 4;
+				pt_regs_clear_syscall(regs);
+			}
+		}
+		restore_saved_sigmask();
+	}
+}
+
+void do_notify_resume(struct pt_regs *regs, unsigned long orig_i0, unsigned long thread_info_flags)
+{
+	user_exit();
+	if (thread_info_flags & _TIF_SIGPENDING)
+		do_signal(regs, orig_i0);
+	if (thread_info_flags & _TIF_NOTIFY_RESUME) {
+		clear_thread_flag(TIF_NOTIFY_RESUME);
+		tracehook_notify_resume(regs);
+	}
+	user_enter();
+}
+