target/mips: Make mips_cpu_tlb_fill sysemu only

The fallback code in cpu_loop_exit_sigsegv is sufficient
for mips linux-user.

This means we can remove tcg/user/tlb_helper.c entirely.
Remove the code from cpu_loop that raised SIGSEGV.

Reviewed-by: Warner Losh <imp@bsdimp.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>

linux-user/mips/cpu_loop.c

@@ -158,17 +158,6 @@ done_syscall:
             }
             env->active_tc.gpr[2] = ret;
             break;
-        case EXCP_TLBL:
-        case EXCP_TLBS:
-        case EXCP_AdEL:
-        case EXCP_AdES:
-            info.si_signo = TARGET_SIGSEGV;
-            info.si_errno = 0;
-            /* XXX: check env->error_code */
-            info.si_code = TARGET_SEGV_MAPERR;
-            info._sifields._sigfault._addr = env->CP0_BadVAddr;
-            queue_signal(env, info.si_signo, QEMU_SI_FAULT, &info);
-            break;
         case EXCP_CpU:
         case EXCP_RI:
             info.si_signo = TARGET_SIGILL;

target/mips/cpu.c

@@ -539,9 +539,9 @@ static const struct SysemuCPUOps mips_sysemu_ops = {
 static const struct TCGCPUOps mips_tcg_ops = {
     .initialize = mips_tcg_init,
     .synchronize_from_tb = mips_cpu_synchronize_from_tb,
-    .tlb_fill = mips_cpu_tlb_fill,
 
 #if !defined(CONFIG_USER_ONLY)
+    .tlb_fill = mips_cpu_tlb_fill,
     .cpu_exec_interrupt = mips_cpu_exec_interrupt,
     .do_interrupt = mips_cpu_do_interrupt,
     .do_transaction_failed = mips_cpu_do_transaction_failed,

target/mips/tcg/meson.build

@@ -28,9 +28,6 @@ mips_ss.add(when: 'TARGET_MIPS64', if_true: files(
   'mxu_translate.c',
 ))
 
-if have_user
-  subdir('user')
-endif
 if have_system
   subdir('sysemu')
 endif

target/mips/tcg/tcg-internal.h

@@ -18,9 +18,6 @@
 void mips_tcg_init(void);
 
 void mips_cpu_synchronize_from_tb(CPUState *cs, const TranslationBlock *tb);
-bool mips_cpu_tlb_fill(CPUState *cs, vaddr address, int size,
-                       MMUAccessType access_type, int mmu_idx,
-                       bool probe, uintptr_t retaddr);
 void mips_cpu_do_unaligned_access(CPUState *cpu, vaddr addr,
                                   MMUAccessType access_type, int mmu_idx,
                                   uintptr_t retaddr) QEMU_NORETURN;
@@ -60,6 +57,10 @@ void mips_cpu_do_transaction_failed(CPUState *cs, hwaddr physaddr,
                                     MemTxResult response, uintptr_t retaddr);
 void cpu_mips_tlb_flush(CPUMIPSState *env);
 
+bool mips_cpu_tlb_fill(CPUState *cs, vaddr address, int size,
+                       MMUAccessType access_type, int mmu_idx,
+                       bool probe, uintptr_t retaddr);
+
 #endif /* !CONFIG_USER_ONLY */
 
 #endif

target/mips/tcg/user/meson.build

@@ -1,3 +0,0 @@
-mips_user_ss.add(files(
-  'tlb_helper.c',
-))

target/mips/tcg/user/tlb_helper.c

@@ -1,59 +0,0 @@
-/*
- * MIPS TLB (Translation lookaside buffer) helpers.
- *
- *  Copyright (c) 2004-2005 Jocelyn Mayer
- *
- * This library is free software; you can redistribute it and/or
- * modify it under the terms of the GNU Lesser General Public
- * License as published by the Free Software Foundation; either
- * version 2.1 of the License, or (at your option) any later version.
- *
- * This library is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
- * Lesser General Public License for more details.
- *
- * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, see <http://www.gnu.org/licenses/>.
- */
-#include "qemu/osdep.h"
-
-#include "cpu.h"
-#include "exec/exec-all.h"
-#include "internal.h"
-
-static void raise_mmu_exception(CPUMIPSState *env, target_ulong address,
-                                MMUAccessType access_type)
-{
-    CPUState *cs = env_cpu(env);
-
-    env->error_code = 0;
-    if (access_type == MMU_INST_FETCH) {
-        env->error_code |= EXCP_INST_NOTAVAIL;
-    }
-
-    /* Reference to kernel address from user mode or supervisor mode */
-    /* Reference to supervisor address from user mode */
-    if (access_type == MMU_DATA_STORE) {
-        cs->exception_index = EXCP_AdES;
-    } else {
-        cs->exception_index = EXCP_AdEL;
-    }
-
-    /* Raise exception */
-    if (!(env->hflags & MIPS_HFLAG_DM)) {
-        env->CP0_BadVAddr = address;
-    }
-}
-
-bool mips_cpu_tlb_fill(CPUState *cs, vaddr address, int size,
-                       MMUAccessType access_type, int mmu_idx,
-                       bool probe, uintptr_t retaddr)
-{
-    MIPSCPU *cpu = MIPS_CPU(cs);
-    CPUMIPSState *env = &cpu->env;
-
-    /* data access */
-    raise_mmu_exception(env, address, access_type);
-    do_raise_exception_err(env, cs->exception_index, env->error_code, retaddr);
-}