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authorLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
committerLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
commit1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch)
tree0bba044c4ce775e45a88a51686b5d9f90697ea9d /drivers/s390/char/sclp_quiesce.c
downloadlinux-dev-1da177e4c3f41524e886b7f1b8a0c1fc7321cac2.tar.xz
linux-dev-1da177e4c3f41524e886b7f1b8a0c1fc7321cac2.zip
Linux-2.6.12-rc2
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
Diffstat (limited to 'drivers/s390/char/sclp_quiesce.c')
-rw-r--r--drivers/s390/char/sclp_quiesce.c99
1 files changed, 99 insertions, 0 deletions
diff --git a/drivers/s390/char/sclp_quiesce.c b/drivers/s390/char/sclp_quiesce.c
new file mode 100644
index 000000000000..83f75774df60
--- /dev/null
+++ b/drivers/s390/char/sclp_quiesce.c
@@ -0,0 +1,99 @@
+/*
+ * drivers/s390/char/sclp_quiesce.c
+ * signal quiesce handler
+ *
+ * (C) Copyright IBM Corp. 1999,2004
+ * Author(s): Martin Schwidefsky <schwidefsky@de.ibm.com>
+ * Peter Oberparleiter <peter.oberparleiter@de.ibm.com>
+ */
+
+#include <linux/config.h>
+#include <linux/module.h>
+#include <linux/types.h>
+#include <linux/cpumask.h>
+#include <linux/smp.h>
+#include <linux/init.h>
+#include <asm/atomic.h>
+#include <asm/ptrace.h>
+#include <asm/sigp.h>
+
+#include "sclp.h"
+
+
+#ifdef CONFIG_SMP
+/* Signal completion of shutdown process. All CPUs except the first to enter
+ * this function: go to stopped state. First CPU: wait until all other
+ * CPUs are in stopped or check stop state. Afterwards, load special PSW
+ * to indicate completion. */
+static void
+do_load_quiesce_psw(void * __unused)
+{
+ static atomic_t cpuid = ATOMIC_INIT(-1);
+ psw_t quiesce_psw;
+ int cpu;
+
+ if (atomic_compare_and_swap(-1, smp_processor_id(), &cpuid))
+ signal_processor(smp_processor_id(), sigp_stop);
+ /* Wait for all other cpus to enter stopped state */
+ for_each_online_cpu(cpu) {
+ if (cpu == smp_processor_id())
+ continue;
+ while(!smp_cpu_not_running(cpu))
+ cpu_relax();
+ }
+ /* Quiesce the last cpu with the special psw */
+ quiesce_psw.mask = PSW_BASE_BITS | PSW_MASK_WAIT;
+ quiesce_psw.addr = 0xfff;
+ __load_psw(quiesce_psw);
+}
+
+/* Shutdown handler. Perform shutdown function on all CPUs. */
+static void
+do_machine_quiesce(void)
+{
+ on_each_cpu(do_load_quiesce_psw, NULL, 0, 0);
+}
+#else
+/* Shutdown handler. Signal completion of shutdown by loading special PSW. */
+static void
+do_machine_quiesce(void)
+{
+ psw_t quiesce_psw;
+
+ quiesce_psw.mask = PSW_BASE_BITS | PSW_MASK_WAIT;
+ quiesce_psw.addr = 0xfff;
+ __load_psw(quiesce_psw);
+}
+#endif
+
+extern void ctrl_alt_del(void);
+
+/* Handler for quiesce event. Start shutdown procedure. */
+static void
+sclp_quiesce_handler(struct evbuf_header *evbuf)
+{
+ _machine_restart = (void *) do_machine_quiesce;
+ _machine_halt = do_machine_quiesce;
+ _machine_power_off = do_machine_quiesce;
+ ctrl_alt_del();
+}
+
+static struct sclp_register sclp_quiesce_event = {
+ .receive_mask = EvTyp_SigQuiesce_Mask,
+ .receiver_fn = sclp_quiesce_handler
+};
+
+/* Initialize quiesce driver. */
+static int __init
+sclp_quiesce_init(void)
+{
+ int rc;
+
+ rc = sclp_register(&sclp_quiesce_event);
+ if (rc)
+ printk(KERN_WARNING "sclp: could not register quiesce handler "
+ "(rc=%d)\n", rc);
+ return rc;
+}
+
+module_init(sclp_quiesce_init);