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!

1 files changed, 219 insertions, 0 deletions

diff --git a/drivers/s390/s390mach.c b/drivers/s390/s390mach.c
new file mode 100644
index 000000000000..ffa996c8a908
--- /dev/null
+++ b/drivers/s390/s390mach.c
@@ -0,0 +1,219 @@
+/*
+ *  drivers/s390/s390mach.c
+ *   S/390 machine check handler
+ *
+ *  S390 version
+ *    Copyright (C) 2000 IBM Deutschland Entwicklung GmbH, IBM Corporation
+ *    Author(s): Ingo Adlung (adlung@de.ibm.com)
+ *		 Martin Schwidefsky (schwidefsky@de.ibm.com)
+ */
+
+#include <linux/config.h>
+#include <linux/init.h>
+#include <linux/sched.h>
+#include <linux/errno.h>
+#include <linux/workqueue.h>
+
+#include <asm/lowcore.h>
+
+#include "s390mach.h"
+
+#define DBG printk
+// #define DBG(args,...) do {} while (0);
+
+static struct semaphore m_sem;
+
+extern int css_process_crw(int);
+extern int chsc_process_crw(void);
+extern int chp_process_crw(int, int);
+extern void css_reiterate_subchannels(void);
+
+extern struct workqueue_struct *slow_path_wq;
+extern struct work_struct slow_path_work;
+
+static void
+s390_handle_damage(char *msg)
+{
+	printk(KERN_EMERG "%s\n", msg);
+#ifdef CONFIG_SMP
+	smp_send_stop();
+#endif
+	disabled_wait((unsigned long) __builtin_return_address(0));
+}
+
+/*
+ * Retrieve CRWs and call function to handle event.
+ *
+ * Note : we currently process CRWs for io and chsc subchannels only
+ */
+static int
+s390_collect_crw_info(void *param)
+{
+	struct crw crw;
+	int ccode, ret, slow;
+	struct semaphore *sem;
+
+	sem = (struct semaphore *)param;
+	/* Set a nice name. */
+	daemonize("kmcheck");
+repeat:
+	down_interruptible(sem);
+	slow = 0;
+	while (1) {
+		ccode = stcrw(&crw);
+		if (ccode != 0)
+			break;
+		DBG(KERN_DEBUG "crw_info : CRW reports slct=%d, oflw=%d, "
+		    "chn=%d, rsc=%X, anc=%d, erc=%X, rsid=%X\n",
+		    crw.slct, crw.oflw, crw.chn, crw.rsc, crw.anc,
+		    crw.erc, crw.rsid);
+		/* Check for overflows. */
+		if (crw.oflw) {
+			pr_debug("%s: crw overflow detected!\n", __FUNCTION__);
+			css_reiterate_subchannels();
+			slow = 1;
+			continue;
+		}
+		switch (crw.rsc) {
+		case CRW_RSC_SCH:
+			pr_debug("source is subchannel %04X\n", crw.rsid);
+			ret = css_process_crw (crw.rsid);
+			if (ret == -EAGAIN)
+				slow = 1;
+			break;
+		case CRW_RSC_MONITOR:
+			pr_debug("source is monitoring facility\n");
+			break;
+		case CRW_RSC_CPATH:
+			pr_debug("source is channel path %02X\n", crw.rsid);
+			switch (crw.erc) {
+			case CRW_ERC_IPARM: /* Path has come. */
+				ret = chp_process_crw(crw.rsid, 1);
+				break;
+			case CRW_ERC_PERRI: /* Path has gone. */
+			case CRW_ERC_PERRN:
+				ret = chp_process_crw(crw.rsid, 0);
+				break;
+			default:
+				pr_debug("Don't know how to handle erc=%x\n",
+					 crw.erc);
+				ret = 0;
+			}
+			if (ret == -EAGAIN)
+				slow = 1;
+			break;
+		case CRW_RSC_CONFIG:
+			pr_debug("source is configuration-alert facility\n");
+			break;
+		case CRW_RSC_CSS:
+			pr_debug("source is channel subsystem\n");
+			ret = chsc_process_crw();
+			if (ret == -EAGAIN)
+				slow = 1;
+			break;
+		default:
+			pr_debug("unknown source\n");
+			break;
+		}
+	}
+	if (slow)
+		queue_work(slow_path_wq, &slow_path_work);
+	goto repeat;
+	return 0;
+}
+
+/*
+ * machine check handler.
+ */
+void
+s390_do_machine_check(void)
+{
+	struct mci *mci;
+
+	mci = (struct mci *) &S390_lowcore.mcck_interruption_code;
+
+	if (mci->sd)		/* system damage */
+		s390_handle_damage("received system damage machine check\n");
+
+	if (mci->pd)		/* instruction processing damage */
+		s390_handle_damage("received instruction processing "
+				   "damage machine check\n");
+
+	if (mci->se)		/* storage error uncorrected */
+		s390_handle_damage("received storage error uncorrected "
+				   "machine check\n");
+
+	if (mci->sc)		/* storage error corrected */
+		printk(KERN_WARNING
+		       "received storage error corrected machine check\n");
+
+	if (mci->ke)		/* storage key-error uncorrected */
+		s390_handle_damage("received storage key-error uncorrected "
+				   "machine check\n");
+
+	if (mci->ds && mci->fa)	/* storage degradation */
+		s390_handle_damage("received storage degradation machine "
+				   "check\n");
+
+	if (mci->cp)		/* channel report word pending */
+		up(&m_sem);
+
+#ifdef CONFIG_MACHCHK_WARNING
+/*
+ * The warning may remain for a prolonged period on the bare iron.
+ * (actually till the machine is powered off, or until the problem is gone)
+ * So we just stop listening for the WARNING MCH and prevent continuously
+ * being interrupted.  One caveat is however, that we must do this per
+ * processor and cannot use the smp version of ctl_clear_bit().
+ * On VM we only get one interrupt per virtally presented machinecheck.
+ * Though one suffices, we may get one interrupt per (virtual) processor.
+ */
+	if (mci->w) {	/* WARNING pending ? */
+		static int mchchk_wng_posted = 0;
+		/*
+		 * Use single machine clear, as we cannot handle smp right now
+		 */
+		__ctl_clear_bit(14, 24);	/* Disable WARNING MCH */
+		if (xchg(&mchchk_wng_posted, 1) == 0)
+			kill_proc(1, SIGPWR, 1);
+	}
+#endif
+}
+
+/*
+ * s390_init_machine_check
+ *
+ * initialize machine check handling
+ */
+static int
+machine_check_init(void)
+{
+	init_MUTEX_LOCKED(&m_sem);
+	ctl_clear_bit(14, 25);	/* disable damage MCH */
+	ctl_set_bit(14, 26);	/* enable degradation MCH */
+	ctl_set_bit(14, 27);	/* enable system recovery MCH */
+#ifdef CONFIG_MACHCHK_WARNING
+	ctl_set_bit(14, 24);	/* enable warning MCH */
+#endif
+	return 0;
+}
+
+/*
+ * Initialize the machine check handler really early to be able to
+ * catch all machine checks that happen during boot
+ */
+arch_initcall(machine_check_init);
+
+/*
+ * Machine checks for the channel subsystem must be enabled
+ * after the channel subsystem is initialized
+ */
+static int __init
+machine_check_crw_init (void)
+{
+	kernel_thread(s390_collect_crw_info, &m_sem, CLONE_FS|CLONE_FILES);
+	ctl_set_bit(14, 28);	/* enable channel report MCH */
+	return 0;
+}
+
+device_initcall (machine_check_crw_init);