1 files changed, 117 insertions, 20 deletions

diff --git a/arch/mips/kernel/signal32.c b/arch/mips/kernel/signal32.c
index 3d60f7750fa8..299f956e4db3 100644
--- a/arch/mips/kernel/signal32.c
+++ b/arch/mips/kernel/signal32.c
@@ -30,6 +30,7 @@
 #include <asm/sim.h>
 #include <asm/ucontext.h>
 #include <asm/fpu.h>
+#include <asm/msa.h>
 #include <asm/war.h>
 #include <asm/vdso.h>
 #include <asm/dsp.h>
@@ -42,8 +43,8 @@ static int (*restore_fp_context32)(struct sigcontext32 __user *sc);
 extern asmlinkage int _save_fp_context32(struct sigcontext32 __user *sc);
 extern asmlinkage int _restore_fp_context32(struct sigcontext32 __user *sc);
 
-extern asmlinkage int fpu_emulator_save_context32(struct sigcontext32 __user *sc);
-extern asmlinkage int fpu_emulator_restore_context32(struct sigcontext32 __user *sc);
+extern asmlinkage int _save_msa_context32(struct sigcontext32 __user *sc);
+extern asmlinkage int _restore_msa_context32(struct sigcontext32 __user *sc);
 
 /*
  * Including <asm/unistd.h> would give use the 64-bit syscall numbers ...
@@ -78,17 +79,96 @@ struct rt_sigframe32 {
 };
 
 /*
+ * 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_sigcontext32(struct sigcontext32 __user *sc)
+{
+        int i;
+        int err = 0;
+        int inc = test_thread_flag(TIF_32BIT_FPREGS) ? 2 : 1;
+
+        for (i = 0; i < NUM_FPU_REGS; i += inc) {
+                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_sigcontext32(struct sigcontext32 __user *sc)
+{
+        int i;
+        int err = 0;
+        int inc = test_thread_flag(TIF_32BIT_FPREGS) ? 2 : 1;
+        u64 fpr_val;
+
+        for (i = 0; i < NUM_FPU_REGS; i += inc) {
+                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_sigcontext32(struct sigcontext32 __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_sigcontext32(struct sigcontext32 __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;
+}
+
+/*
  * sigcontext handlers
  */
-static int protected_save_fp_context32(struct sigcontext32 __user *sc)
+static int protected_save_fp_context32(struct sigcontext32 __user *sc,
+                                       unsigned used_math)
 {
         int err;
+        bool save_msa = cpu_has_msa && (used_math & USEDMATH_MSA);
         while (1) {
                 lock_fpu_owner();
-                err = own_fpu_inatomic(1);
-                if (!err)
-                        err = save_fp_context32(sc); /* this might fail */
-                unlock_fpu_owner();
+                if (is_fpu_owner()) {
+                        err = save_fp_context32(sc);
+                        if (save_msa && !err)
+                                err = _save_msa_context32(sc);
+                        unlock_fpu_owner();
+                } else {
+                        unlock_fpu_owner();
+                        err = copy_fp_to_sigcontext32(sc);
+                        if (save_msa && !err)
+                                err = copy_msa_to_sigcontext32(sc);
+                }
                 if (likely(!err))
                         break;
                 /* touch the sigcontext and try again */
@@ -101,15 +181,29 @@ static int protected_save_fp_context32(struct sigcontext32 __user *sc)
         return err;
 }
 
-static int protected_restore_fp_context32(struct sigcontext32 __user *sc)
+static int protected_restore_fp_context32(struct sigcontext32 __user *sc,
+                                          unsigned used_math)
 {
         int err, tmp __maybe_unused;
+        bool restore_msa = cpu_has_msa && (used_math & USEDMATH_MSA);
         while (1) {
                 lock_fpu_owner();
-                err = own_fpu_inatomic(0);
-                if (!err)
-                        err = restore_fp_context32(sc); /* this might fail */
-                unlock_fpu_owner();
+                if (is_fpu_owner()) {
+                        err = restore_fp_context32(sc);
+                        if (restore_msa && !err) {
+                                enable_msa();
+                                err = _restore_msa_context32(sc);
+                        } else {
+                                /* signal handler may have used MSA */
+                                disable_msa();
+                        }
+                        unlock_fpu_owner();
+                } else {
+                        unlock_fpu_owner();
+                        err = copy_fp_from_sigcontext32(sc);
+                        if (restore_msa && !err)
+                                err = copy_msa_from_sigcontext32(sc);
+                }
                 if (likely(!err))
                         break;
                 /* touch the sigcontext and try again */
@@ -147,7 +241,8 @@ static int setup_sigcontext32(struct pt_regs *regs,
                 err |= __put_user(mflo3(), &sc->sc_lo3);
         }
 
-        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) {
@@ -155,20 +250,21 @@ static int setup_sigcontext32(struct pt_regs *regs,
                  * Save FPU state to signal context.  Signal handler
                  * will "inherit" current FPU state.
                  */
-                err |= protected_save_fp_context32(sc);
+                err |= protected_save_fp_context32(sc, used_math);
         }
         return err;
 }
 
 static int
-check_and_restore_fp_context32(struct sigcontext32 __user *sc)
+check_and_restore_fp_context32(struct sigcontext32 __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_context32(sc);
+        err |= protected_restore_fp_context32(sc, used_math);
         return err ?: sig;
 }
 
@@ -205,9 +301,10 @@ static int restore_sigcontext32(struct pt_regs *regs,
         if (used_math) {
                 /* restore fpu context if we have used it before */
                 if (!err)
-                        err = check_and_restore_fp_context32(sc);
+                        err = check_and_restore_fp_context32(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);
         }
 
@@ -566,8 +663,8 @@ static int signal32_init(void)
                 save_fp_context32 = _save_fp_context32;
                 restore_fp_context32 = _restore_fp_context32;
         } else {
-                save_fp_context32 = fpu_emulator_save_context32;
-                restore_fp_context32 = fpu_emulator_restore_context32;
+                save_fp_context32 = copy_fp_to_sigcontext32;
+                restore_fp_context32 = copy_fp_from_sigcontext32;
         }
 
         return 0;