Merge master.kernel.org:/pub/scm/linux/kernel/git/herbert/crypto-2.6

[linux-drm-fsl-dcu.git] / arch / mips / kernel / signal32.c

diff --git a/arch/mips/kernel/signal32.c b/arch/mips/kernel/signal32.c
index 19bbef001959ce9fe0305867f9af3379d4203604..003f8152b9ed7e6ea7383358872a7bab98c1b682 100644 (file)
--- a/arch/mips/kernel/signal32.c
+++ b/arch/mips/kernel/signal32.c
@@ -12,7 +12,6 @@
 #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/syscalls.h>
@@ -22,6 +21,7 @@
 #include <linux/compat.h>
 #include <linux/suspend.h>
 #include <linux/compiler.h>
+#include <linux/uaccess.h>
 
 #include <asm/abi.h>
 #include <asm/asm.h>
@@ -29,7 +29,6 @@
 #include <linux/bitops.h>
 #include <asm/cacheflush.h>
 #include <asm/sim.h>
-#include <asm/uaccess.h>
 #include <asm/ucontext.h>
 #include <asm/system.h>
 #include <asm/fpu.h>
@@ -176,11 +175,52 @@ struct rt_sigframe32 {
 /*
  * sigcontext handlers
  */
+static int protected_save_fp_context32(struct sigcontext32 __user *sc)
+{
+       int err;
+       while (1) {
+               lock_fpu_owner();
+               own_fpu_inatomic(1);
+               err = save_fp_context32(sc); /* this might fail */
+               unlock_fpu_owner();
+               if (likely(!err))
+                       break;
+               /* touch the sigcontext and try again */
+               err = __put_user(0, &sc->sc_fpregs[0]) |
+                       __put_user(0, &sc->sc_fpregs[31]) |
+                       __put_user(0, &sc->sc_fpc_csr);
+               if (err)
+                       break;  /* really bad sigcontext */
+       }
+       return err;
+}
+
+static int protected_restore_fp_context32(struct sigcontext32 __user *sc)
+{
+       int err, tmp;
+       while (1) {
+               lock_fpu_owner();
+               own_fpu_inatomic(0);
+               err = restore_fp_context32(sc); /* this might fail */
+               unlock_fpu_owner();
+               if (likely(!err))
+                       break;
+               /* touch the sigcontext and try again */
+               err = __get_user(tmp, &sc->sc_fpregs[0]) |
+                       __get_user(tmp, &sc->sc_fpregs[31]) |
+                       __get_user(tmp, &sc->sc_fpc_csr);
+               if (err)
+                       break;  /* really bad sigcontext */
+       }
+       return err;
+}
+
 static int setup_sigcontext32(struct pt_regs *regs,
                              struct sigcontext32 __user *sc)
 {
        int err = 0;
        int i;
+       u32 used_math;
 
        err |= __put_user(regs->cp0_epc, &sc->sc_pc);
 
@@ -200,26 +240,31 @@ static int setup_sigcontext32(struct pt_regs *regs,
                err |= __put_user(mflo3(), &sc->sc_lo3);
        }
 
-       err |= __put_user(!!used_math(), &sc->sc_used_math);
+       used_math = !!used_math();
+       err |= __put_user(used_math, &sc->sc_used_math);
 
-       if (used_math()) {
+       if (used_math) {
                /*
                 * Save FPU state to signal context.  Signal handler
                 * will "inherit" current FPU state.
                 */
-               preempt_disable();
-
-               if (!is_fpu_owner()) {
-                       own_fpu();
-                       restore_fp(current);
-               }
-               err |= save_fp_context32(sc);
-
-               preempt_enable();
+               err |= protected_save_fp_context32(sc);
        }
        return err;
 }
 
+static int
+check_and_restore_fp_context32(struct sigcontext32 __user *sc)
+{
+       int err, sig;
+
+       err = sig = fpcsr_pending(&sc->sc_fpc_csr);
+       if (err > 0)
+               err = 0;
+       err |= protected_restore_fp_context32(sc);
+       return err ?: sig;
+}
+
 static int restore_sigcontext32(struct pt_regs *regs,
                                struct sigcontext32 __user *sc)
 {
@@ -250,19 +295,15 @@ static int restore_sigcontext32(struct pt_regs *regs,
        err |= __get_user(used_math, &sc->sc_used_math);
        conditional_used_math(used_math);
 
-       preempt_disable();
-
-       if (used_math()) {
+       if (used_math) {
                /* restore fpu context if we have used it before */
-               own_fpu();
-               err |= restore_fp_context32(sc);
+               if (!err)
+                       err = check_and_restore_fp_context32(sc);
        } else {
                /* signal handler may have used FPU.  Give it up. */
-               lose_fpu();
+               lose_fpu(0);
        }
 
-       preempt_enable();
-
        return err;
 }
 
@@ -508,6 +549,7 @@ asmlinkage void sys32_sigreturn(nabi_no_regargs struct pt_regs regs)
 {
        struct sigframe32 __user *frame;
        sigset_t blocked;
+       int sig;
 
        frame = (struct sigframe32 __user *) regs.regs[29];
        if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
@@ -521,8 +563,11 @@ asmlinkage void sys32_sigreturn(nabi_no_regargs struct pt_regs regs)
        recalc_sigpending();
        spin_unlock_irq(&current->sighand->siglock);
 
-       if (restore_sigcontext32(&regs, &frame->sf_sc))
+       sig = restore_sigcontext32(&regs, &frame->sf_sc);
+       if (sig < 0)
                goto badframe;
+       else if (sig)
+               force_sig(sig, current);
 
        /*
         * Don't let your children do this ...
@@ -545,6 +590,7 @@ asmlinkage void sys32_rt_sigreturn(nabi_no_regargs struct pt_regs regs)
        sigset_t set;
        stack_t st;
        s32 sp;
+       int sig;
 
        frame = (struct rt_sigframe32 __user *) regs.regs[29];
        if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
@@ -558,8 +604,11 @@ asmlinkage void sys32_rt_sigreturn(nabi_no_regargs struct pt_regs regs)
        recalc_sigpending();
        spin_unlock_irq(&current->sighand->siglock);
 
-       if (restore_sigcontext32(&regs, &frame->rs_uc.uc_mcontext))
+       sig = restore_sigcontext32(&regs, &frame->rs_uc.uc_mcontext);
+       if (sig < 0)
                goto badframe;
+       else if (sig)
+               force_sig(sig, current);
 
        /* The ucontext contains a stack32_t, so we must convert!  */
        if (__get_user(sp, &frame->rs_uc.uc_stack.ss_sp))