[Qemu-devel] [PATCH][RESEND] Add monitor command for system_reboot

[Ryan Harper <ryanh@us.ibm.com>]

Add a new monitor command (system_reboot) for a soft reboot which uses
system_powerdown to trigger ACPI shutdown in the guest and once shutdown
is complete, trigger a reset instead of exiting qemu.

Depends on commit a6d6552426dcbf726e5549f08b70c9318d6be14b which enabled
ACPI power button support.

V2:
    -added reset handler to lower the reboot flag on reset.

Tested with:
    - Ubuntu 9.04 64-bit guest.
    - SLES 10 SP2 32-bit guest.
    - RHEL 5.3 32 and 64 bit guests.

-- 
Ryan Harper
Software Engineer; Linux Technology Center
IBM Corp., Austin, Tx
ryanh@us.ibm.com


diffstat output:
 hw/acpi.c       |   15 ++++++++++++++-
 monitor.c       |    5 +++++
 qemu-monitor.hx |    8 ++++++++
 sysemu.h        |    2 ++
 vl.c            |   22 +++++++++++++++++++++-
 5 files changed, 50 insertions(+), 2 deletions(-)

---
From: Ryan Harper <ryanh@us.ibm.com>
Subject: [PATCH] Add system_reboot monitor function
Cc: Anthony Liguori <aliguori@us.ibm.com>

This patch adds a new monitor command to trigger a powerdown followed by
system_reset.

Signed-off-by: Ryan Harper <ryanh@us.ibm.com>
---
 hw/acpi.c       |   15 ++++++++++++++-
 monitor.c       |    5 +++++
 qemu-monitor.hx |    8 ++++++++
 sysemu.h        |    2 ++
 vl.c            |   21 +++++++++++++++++++++
 5 files changed, 50 insertions(+), 1 deletions(-)

diff --git a/hw/acpi.c b/hw/acpi.c
index 0465201..aba384c 100644
--- a/hw/acpi.c
+++ b/hw/acpi.c
@@ -151,7 +151,13 @@ static void pm_ioport_writew(void *opaque, uint32_t addr, uint32_t val)
                 sus_typ = (val >> 10) & 7;
                 switch(sus_typ) {
                 case 0: /* soft power off */
-                    qemu_system_shutdown_request();
+                    /* after powerdown, if on system_reboot path, call reset 
+                       instead of shutdown */
+                    if (qemu_reboot_requested()) {
+                        qemu_system_reset_request();
+                    } else {
+                        qemu_system_shutdown_request();
+                    }
                     break;
                 case 1:
                     /* RSM_STS should be set on resume. Pretend that resume
@@ -497,6 +503,12 @@ static void piix4_reset(void *opaque)
     }
 }
 
+static void system_reboot_reset(void *opaque)
+{
+    /* clear reboot flag */
+    qemu_reboot_requested();
+}
+
 i2c_bus *piix4_pm_init(PCIBus *bus, int devfn, uint32_t smb_io_base,
                        qemu_irq sci_irq)
 {
@@ -551,6 +563,7 @@ i2c_bus *piix4_pm_init(PCIBus *bus, int devfn, uint32_t smb_io_base,
     s->smbus = i2c_init_bus(NULL, "i2c");
     s->irq = sci_irq;
     qemu_register_reset(piix4_reset, s);
+    qemu_register_reset(system_reboot_reset, s);
 
     return s->smbus;
 }
diff --git a/monitor.c b/monitor.c
index bad79fe..346e0db 100644
--- a/monitor.c
+++ b/monitor.c
@@ -1223,6 +1223,11 @@ static void do_system_powerdown(Monitor *mon)
     qemu_system_powerdown_request();
 }
 
+static void do_system_reboot(Monitor *mon)
+{
+    qemu_system_reboot_request();
+}
+
 #if defined(TARGET_I386)
 static void print_pte(Monitor *mon, uint32_t addr, uint32_t pte, uint32_t mask)
 {
diff --git a/qemu-monitor.hx b/qemu-monitor.hx
index dc10b75..91799d0 100644
--- a/qemu-monitor.hx
+++ b/qemu-monitor.hx
@@ -339,6 +339,14 @@ STEXI
 Power down the system (if supported).
 ETEXI
 
+    { "system_reboot", "", do_system_reboot,
+      "", "send system power down event, and then reset" },
+STEXI
+@item system_reboot
+
+Power down the system (if supported), and then reset.
+ETEXI
+
     { "sum", "ii", do_sum,
       "addr size", "compute the checksum of a memory region" },
 STEXI
diff --git a/sysemu.h b/sysemu.h
index 06dc4c6..056a491 100644
--- a/sysemu.h
+++ b/sysemu.h
@@ -40,10 +40,12 @@ void cpu_enable_ticks(void);
 void cpu_disable_ticks(void);
 
 void qemu_system_reset_request(void);
+void qemu_system_reboot_request(void);
 void qemu_system_shutdown_request(void);
 void qemu_system_powerdown_request(void);
 int qemu_shutdown_requested(void);
 int qemu_reset_requested(void);
+int qemu_reboot_requested(void);
 int qemu_powerdown_requested(void);
 #ifdef NEED_CPU_H
 #if !defined(TARGET_SPARC) && !defined(TARGET_I386)
diff --git a/vl.c b/vl.c
index 7b7489c..634d386 100644
--- a/vl.c
+++ b/vl.c
@@ -3618,6 +3618,7 @@ static QEMUResetEntry *first_reset_entry;
 static int reset_requested;
 static int shutdown_requested;
 static int powerdown_requested;
+static int reboot_requested;
 static int debug_requested;
 static int vmstop_requested;
 
@@ -3642,6 +3643,13 @@ int qemu_powerdown_requested(void)
     return r;
 }
 
+int qemu_reboot_requested(void)
+{
+    int r = reboot_requested;
+    reboot_requested = 0;
+    return r;
+}
+
 static int qemu_debug_requested(void)
 {
     int r = debug_requested;
@@ -3712,6 +3720,17 @@ void qemu_system_powerdown_request(void)
     qemu_notify_event();
 }
 
+void qemu_system_reboot_request(void)
+{
+    /* Raise the powerdown request to trigger system_powerdown event.
+     * Also raise reboot flag so powerdown handler knows to request
+     * a reset instead of shutdown after the powerdown.
+     */
+    powerdown_requested = 1;
+    reboot_requested = 1;
+    qemu_notify_event();
+}
+
 #ifdef CONFIG_IOTHREAD
 static void qemu_system_vmstop_request(int reason)
 {
@@ -4461,6 +4480,8 @@ static int vm_can_run(void)
 {
     if (powerdown_requested)
         return 0;
+    if (reboot_requested)
+        return 0;
     if (reset_requested)
         return 0;
     if (shutdown_requested)
-- 
1.6.0.4