[PATCH 02/21] system: move SIGBUS signal handling to signal.c

["Daniel P. Berrangé" <berrange@redhat.com>]

Introduce a new file 'system/signal.c' to hold the SIGBUS signal
handler, since subsequent commits are going to expand the signal
handling logic somewhat.

The existing copyright header/license boilerplate is retained
instead of a SPDX tag, to respect historic context.

Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
---
 MAINTAINERS             |   2 +
 include/system/signal.h |  25 ++++++++++
 system/cpus.c           |  76 +---------------------------
 system/meson.build      |   1 +
 system/signal.c         | 107 ++++++++++++++++++++++++++++++++++++++++
 5 files changed, 136 insertions(+), 75 deletions(-)
 create mode 100644 include/system/signal.h
 create mode 100644 system/signal.c

diff --git a/MAINTAINERS b/MAINTAINERS
index fc60193aa3f..6b5aafe43b1 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -553,6 +553,7 @@ F: include/exec/target_long.h
 F: include/qemu/accel.h
 F: include/system/accel-*.h
 F: include/system/cpus.h
+F: include/system/signal.h
 F: include/accel/accel-*.h
 F: accel/accel-*.?
 F: accel/dummy-cpus.?
@@ -562,6 +563,7 @@ F: cpu-common.c
 F: cpu-target.c
 F: qapi/accelerator.json
 F: system/cpus.c
+F: system/signal.c
 
 Apple Silicon HVF CPUs
 M: Alexander Graf <agraf@csgraf.de>
diff --git a/include/system/signal.h b/include/system/signal.h
new file mode 100644
index 00000000000..f8d00221bcf
--- /dev/null
+++ b/include/system/signal.h
@@ -0,0 +1,25 @@
+/*
+ * QEMU System Emulator
+ *
+ * Copyright (c) 2003-2008 Fabrice Bellard
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+void qemu_init_sigbus(void);
diff --git a/system/cpus.c b/system/cpus.c
index e11a5aab6a6..b231ca4c4ac 100644
--- a/system/cpus.c
+++ b/system/cpus.c
@@ -39,28 +39,11 @@
 #include "system/runstate.h"
 #include "system/cpu-timers.h"
 #include "system/whpx.h"
+#include "system/signal.h"
 #include "hw/core/boards.h"
 #include "hw/core/hw-error.h"
 #include "trace.h"
 
-#ifdef CONFIG_LINUX
-
-#include <sys/prctl.h>
-
-#ifndef PR_MCE_KILL
-#define PR_MCE_KILL 33
-#endif
-
-#ifndef PR_MCE_KILL_SET
-#define PR_MCE_KILL_SET 1
-#endif
-
-#ifndef PR_MCE_KILL_EARLY
-#define PR_MCE_KILL_EARLY 1
-#endif
-
-#endif /* CONFIG_LINUX */
-
 /* The Big QEMU Lock (BQL) */
 static QemuMutex bql;
 
@@ -302,63 +285,6 @@ void cpu_handle_guest_debug(CPUState *cpu)
     }
 }
 
-#ifdef CONFIG_LINUX
-static void sigbus_reraise(void)
-{
-    sigset_t set;
-    struct sigaction action;
-
-    memset(&action, 0, sizeof(action));
-    action.sa_handler = SIG_DFL;
-    if (!sigaction(SIGBUS, &action, NULL)) {
-        raise(SIGBUS);
-        sigemptyset(&set);
-        sigaddset(&set, SIGBUS);
-        pthread_sigmask(SIG_UNBLOCK, &set, NULL);
-    }
-    perror("Failed to re-raise SIGBUS!");
-    abort();
-}
-
-static void sigbus_handler(int n, siginfo_t *siginfo, void *ctx)
-{
-    if (siginfo->si_code != BUS_MCEERR_AO && siginfo->si_code != BUS_MCEERR_AR) {
-        sigbus_reraise();
-    }
-
-    if (current_cpu) {
-        /* Called asynchronously in VCPU thread.  */
-        if (kvm_on_sigbus_vcpu(current_cpu, siginfo->si_code, siginfo->si_addr)) {
-            sigbus_reraise();
-        }
-    } else {
-        /* Called synchronously (via signalfd) in main thread.  */
-        if (kvm_on_sigbus(siginfo->si_code, siginfo->si_addr)) {
-            sigbus_reraise();
-        }
-    }
-}
-
-static void qemu_init_sigbus(void)
-{
-    struct sigaction action;
-
-    /*
-     * ALERT: when modifying this, take care that SIGBUS forwarding in
-     * qemu_prealloc_mem() will continue working as expected.
-     */
-    memset(&action, 0, sizeof(action));
-    action.sa_flags = SA_SIGINFO;
-    action.sa_sigaction = sigbus_handler;
-    sigaction(SIGBUS, &action, NULL);
-
-    prctl(PR_MCE_KILL, PR_MCE_KILL_SET, PR_MCE_KILL_EARLY, 0, 0);
-}
-#else /* !CONFIG_LINUX */
-static void qemu_init_sigbus(void)
-{
-}
-#endif /* !CONFIG_LINUX */
 
 static QemuThread io_thread;
 
diff --git a/system/meson.build b/system/meson.build
index a6ba7a04f7d..1829de3d25b 100644
--- a/system/meson.build
+++ b/system/meson.build
@@ -24,6 +24,7 @@ system_ss.add(files(
   'rtc.c',
   'runstate-action.c',
   'runstate.c',
+  'signal.c',
   'watchpoint.c',
 ))
 
diff --git a/system/signal.c b/system/signal.c
new file mode 100644
index 00000000000..6d69db2bc79
--- /dev/null
+++ b/system/signal.c
@@ -0,0 +1,107 @@
+/*
+ * QEMU System Emulator
+ *
+ * Copyright (c) 2003-2008 Fabrice Bellard
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+#include "qemu/osdep.h"
+#include "system/signal.h"
+#include "hw/core/cpu.h"
+#include "system/kvm.h"
+
+#ifdef CONFIG_LINUX
+
+#include <sys/prctl.h>
+
+#ifndef PR_MCE_KILL
+#define PR_MCE_KILL 33
+#endif
+
+#ifndef PR_MCE_KILL_SET
+#define PR_MCE_KILL_SET 1
+#endif
+
+#ifndef PR_MCE_KILL_EARLY
+#define PR_MCE_KILL_EARLY 1
+#endif
+
+#endif /* CONFIG_LINUX */
+
+
+#ifdef CONFIG_LINUX
+static void sigbus_reraise(void)
+{
+    sigset_t set;
+    struct sigaction action;
+
+    memset(&action, 0, sizeof(action));
+    action.sa_handler = SIG_DFL;
+    if (!sigaction(SIGBUS, &action, NULL)) {
+        raise(SIGBUS);
+        sigemptyset(&set);
+        sigaddset(&set, SIGBUS);
+        pthread_sigmask(SIG_UNBLOCK, &set, NULL);
+    }
+    perror("Failed to re-raise SIGBUS!");
+    abort();
+}
+
+static void sigbus_handler(int n, siginfo_t *siginfo, void *ctx)
+{
+    if (siginfo->si_code != BUS_MCEERR_AO &&
+        siginfo->si_code != BUS_MCEERR_AR) {
+        sigbus_reraise();
+    }
+
+    if (current_cpu) {
+        /* Called asynchronously in VCPU thread.  */
+        if (kvm_on_sigbus_vcpu(current_cpu, siginfo->si_code,
+                               siginfo->si_addr)) {
+            sigbus_reraise();
+        }
+    } else {
+        /* Called synchronously (via signalfd) in main thread.  */
+        if (kvm_on_sigbus(siginfo->si_code, siginfo->si_addr)) {
+            sigbus_reraise();
+        }
+    }
+}
+
+void qemu_init_sigbus(void)
+{
+    struct sigaction action;
+
+    /*
+     * ALERT: when modifying this, take care that SIGBUS forwarding in
+     * qemu_prealloc_mem() will continue working as expected.
+     */
+    memset(&action, 0, sizeof(action));
+    action.sa_flags = SA_SIGINFO;
+    action.sa_sigaction = sigbus_handler;
+    sigaction(SIGBUS, &action, NULL);
+
+    prctl(PR_MCE_KILL, PR_MCE_KILL_SET, PR_MCE_KILL_EARLY, 0, 0);
+}
+#else /* !CONFIG_LINUX */
+void qemu_init_sigbus(void)
+{
+}
+#endif /* !CONFIG_LINUX */
-- 
2.56.0