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Diffstat (limited to 'arch/mips/kernel/signal.c')
-rw-r--r--arch/mips/kernel/signal.c170
1 files changed, 148 insertions, 22 deletions
diff --git a/arch/mips/kernel/signal.c b/arch/mips/kernel/signal.c
index 5199563c4403..33133d3df3e5 100644
--- a/arch/mips/kernel/signal.c
+++ b/arch/mips/kernel/signal.c
@@ -6,6 +6,7 @@
* Copyright (C) 1991, 1992 Linus Torvalds
* Copyright (C) 1994 - 2000 Ralf Baechle
* Copyright (C) 1999, 2000 Silicon Graphics, Inc.
+ * Copyright (C) 2014, Imagination Technologies Ltd.
*/
#include <linux/cache.h>
#include <linux/context_tracking.h>
@@ -30,6 +31,7 @@
#include <linux/bitops.h>
#include <asm/cacheflush.h>
#include <asm/fpu.h>
+#include <asm/msa.h>
#include <asm/sim.h>
#include <asm/ucontext.h>
#include <asm/cpu-features.h>
@@ -46,8 +48,8 @@ static int (*restore_fp_context)(struct sigcontext __user *sc);
extern asmlinkage int _save_fp_context(struct sigcontext __user *sc);
extern asmlinkage int _restore_fp_context(struct sigcontext __user *sc);
-extern asmlinkage int fpu_emulator_save_context(struct sigcontext __user *sc);
-extern asmlinkage int fpu_emulator_restore_context(struct sigcontext __user *sc);
+extern asmlinkage int _save_msa_context(struct sigcontext __user *sc);
+extern asmlinkage int _restore_msa_context(struct sigcontext __user *sc);
struct sigframe {
u32 sf_ass[4]; /* argument save space for o32 */
@@ -64,17 +66,95 @@ struct rt_sigframe {
};
/*
+ * Thread saved context copy to/from a signal context presumed to be on the
+ * user stack, and therefore accessed with appropriate macros from uaccess.h.
+ */
+static int copy_fp_to_sigcontext(struct sigcontext __user *sc)
+{
+ int i;
+ int err = 0;
+
+ for (i = 0; i < NUM_FPU_REGS; i++) {
+ err |=
+ __put_user(get_fpr64(&current->thread.fpu.fpr[i], 0),
+ &sc->sc_fpregs[i]);
+ }
+ err |= __put_user(current->thread.fpu.fcr31, &sc->sc_fpc_csr);
+
+ return err;
+}
+
+static int copy_fp_from_sigcontext(struct sigcontext __user *sc)
+{
+ int i;
+ int err = 0;
+ u64 fpr_val;
+
+ for (i = 0; i < NUM_FPU_REGS; i++) {
+ err |= __get_user(fpr_val, &sc->sc_fpregs[i]);
+ set_fpr64(&current->thread.fpu.fpr[i], 0, fpr_val);
+ }
+ err |= __get_user(current->thread.fpu.fcr31, &sc->sc_fpc_csr);
+
+ return err;
+}
+
+/*
+ * These functions will save only the upper 64 bits of the vector registers,
+ * since the lower 64 bits have already been saved as the scalar FP context.
+ */
+static int copy_msa_to_sigcontext(struct sigcontext __user *sc)
+{
+ int i;
+ int err = 0;
+
+ for (i = 0; i < NUM_FPU_REGS; i++) {
+ err |=
+ __put_user(get_fpr64(&current->thread.fpu.fpr[i], 1),
+ &sc->sc_msaregs[i]);
+ }
+ err |= __put_user(current->thread.fpu.msacsr, &sc->sc_msa_csr);
+
+ return err;
+}
+
+static int copy_msa_from_sigcontext(struct sigcontext __user *sc)
+{
+ int i;
+ int err = 0;
+ u64 val;
+
+ for (i = 0; i < NUM_FPU_REGS; i++) {
+ err |= __get_user(val, &sc->sc_msaregs[i]);
+ set_fpr64(&current->thread.fpu.fpr[i], 1, val);
+ }
+ err |= __get_user(current->thread.fpu.msacsr, &sc->sc_msa_csr);
+
+ return err;
+}
+
+/*
* Helper routines
*/
-static int protected_save_fp_context(struct sigcontext __user *sc)
+static int protected_save_fp_context(struct sigcontext __user *sc,
+ unsigned used_math)
{
int err;
+ bool save_msa = cpu_has_msa && (used_math & USEDMATH_MSA);
+#ifndef CONFIG_EVA
while (1) {
lock_fpu_owner();
- err = own_fpu_inatomic(1);
- if (!err)
- err = save_fp_context(sc); /* this might fail */
- unlock_fpu_owner();
+ if (is_fpu_owner()) {
+ err = save_fp_context(sc);
+ if (save_msa && !err)
+ err = _save_msa_context(sc);
+ unlock_fpu_owner();
+ } else {
+ unlock_fpu_owner();
+ err = copy_fp_to_sigcontext(sc);
+ if (save_msa && !err)
+ err = copy_msa_to_sigcontext(sc);
+ }
if (likely(!err))
break;
/* touch the sigcontext and try again */
@@ -84,18 +164,44 @@ static int protected_save_fp_context(struct sigcontext __user *sc)
if (err)
break; /* really bad sigcontext */
}
+#else
+ /*
+ * EVA does not have FPU EVA instructions so saving fpu context directly
+ * does not work.
+ */
+ disable_msa();
+ lose_fpu(1);
+ err = save_fp_context(sc); /* this might fail */
+ if (save_msa && !err)
+ err = copy_msa_to_sigcontext(sc);
+#endif
return err;
}
-static int protected_restore_fp_context(struct sigcontext __user *sc)
+static int protected_restore_fp_context(struct sigcontext __user *sc,
+ unsigned used_math)
{
int err, tmp __maybe_unused;
+ bool restore_msa = cpu_has_msa && (used_math & USEDMATH_MSA);
+#ifndef CONFIG_EVA
while (1) {
lock_fpu_owner();
- err = own_fpu_inatomic(0);
- if (!err)
- err = restore_fp_context(sc); /* this might fail */
- unlock_fpu_owner();
+ if (is_fpu_owner()) {
+ err = restore_fp_context(sc);
+ if (restore_msa && !err) {
+ enable_msa();
+ err = _restore_msa_context(sc);
+ } else {
+ /* signal handler may have used MSA */
+ disable_msa();
+ }
+ unlock_fpu_owner();
+ } else {
+ unlock_fpu_owner();
+ err = copy_fp_from_sigcontext(sc);
+ if (!err && (used_math & USEDMATH_MSA))
+ err = copy_msa_from_sigcontext(sc);
+ }
if (likely(!err))
break;
/* touch the sigcontext and try again */
@@ -105,6 +211,17 @@ static int protected_restore_fp_context(struct sigcontext __user *sc)
if (err)
break; /* really bad sigcontext */
}
+#else
+ /*
+ * EVA does not have FPU EVA instructions so restoring fpu context
+ * directly does not work.
+ */
+ enable_msa();
+ lose_fpu(0);
+ err = restore_fp_context(sc); /* this might fail */
+ if (restore_msa && !err)
+ err = copy_msa_from_sigcontext(sc);
+#endif
return err;
}
@@ -135,7 +252,8 @@ int setup_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc)
err |= __put_user(rddsp(DSP_MASK), &sc->sc_dsp);
}
- used_math = !!used_math();
+ used_math = used_math() ? USEDMATH_FP : 0;
+ used_math |= thread_msa_context_live() ? USEDMATH_MSA : 0;
err |= __put_user(used_math, &sc->sc_used_math);
if (used_math) {
@@ -143,7 +261,7 @@ int setup_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc)
* Save FPU state to signal context. Signal handler
* will "inherit" current FPU state.
*/
- err |= protected_save_fp_context(sc);
+ err |= protected_save_fp_context(sc, used_math);
}
return err;
}
@@ -168,14 +286,14 @@ int fpcsr_pending(unsigned int __user *fpcsr)
}
static int
-check_and_restore_fp_context(struct sigcontext __user *sc)
+check_and_restore_fp_context(struct sigcontext __user *sc, unsigned used_math)
{
int err, sig;
err = sig = fpcsr_pending(&sc->sc_fpc_csr);
if (err > 0)
err = 0;
- err |= protected_restore_fp_context(sc);
+ err |= protected_restore_fp_context(sc, used_math);
return err ?: sig;
}
@@ -215,9 +333,10 @@ int restore_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc)
if (used_math) {
/* restore fpu context if we have used it before */
if (!err)
- err = check_and_restore_fp_context(sc);
+ err = check_and_restore_fp_context(sc, used_math);
} else {
- /* signal handler may have used FPU. Give it up. */
+ /* signal handler may have used FPU or MSA. Disable them. */
+ disable_msa();
lose_fpu(0);
}
@@ -591,23 +710,26 @@ asmlinkage void do_notify_resume(struct pt_regs *regs, void *unused,
}
#ifdef CONFIG_SMP
+#ifndef CONFIG_EVA
static int smp_save_fp_context(struct sigcontext __user *sc)
{
return raw_cpu_has_fpu
? _save_fp_context(sc)
- : fpu_emulator_save_context(sc);
+ : copy_fp_to_sigcontext(sc);
}
static int smp_restore_fp_context(struct sigcontext __user *sc)
{
return raw_cpu_has_fpu
? _restore_fp_context(sc)
- : fpu_emulator_restore_context(sc);
+ : copy_fp_from_sigcontext(sc);
}
+#endif /* CONFIG_EVA */
#endif
static int signal_setup(void)
{
+#ifndef CONFIG_EVA
#ifdef CONFIG_SMP
/* For now just do the cpu_has_fpu check when the functions are invoked */
save_fp_context = smp_save_fp_context;
@@ -617,9 +739,13 @@ static int signal_setup(void)
save_fp_context = _save_fp_context;
restore_fp_context = _restore_fp_context;
} else {
- save_fp_context = fpu_emulator_save_context;
- restore_fp_context = fpu_emulator_restore_context;
+ save_fp_context = copy_fp_from_sigcontext;
+ restore_fp_context = copy_fp_to_sigcontext;
}
+#endif /* CONFIG_SMP */
+#else
+ save_fp_context = copy_fp_from_sigcontext;;
+ restore_fp_context = copy_fp_to_sigcontext;
#endif
return 0;
generated by cgit v1.2.3 (git 2.25.1) at 2024-04-25 00:38:18 +0000