[S390] split/move machine check handler code

Split machine check handler code and move it to cio and kernel code
where it belongs to. No functional change.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

1 files changed, 0 insertions, 537 deletions

diff --git a/drivers/s390/s390mach.c b/drivers/s390/s390mach.c
deleted file mode 100644
index 8e437052e076..000000000000
--- a/drivers/s390/s390mach.c
+++ /dev/null
@@ -1,537 +0,0 @@
-/*
- *  drivers/s390/s390mach.c
- *   S/390 machine check handler
- *
- *    Copyright IBM Corp. 2000,2008
- *    Author(s): Ingo Adlung (adlung@de.ibm.com)
- *		 Martin Schwidefsky (schwidefsky@de.ibm.com)
- *		 Cornelia Huck <cornelia.huck@de.ibm.com>
- */
-
-#include <linux/init.h>
-#include <linux/sched.h>
-#include <linux/errno.h>
-#include <linux/workqueue.h>
-#include <linux/time.h>
-#include <linux/device.h>
-#include <linux/kthread.h>
-#include <asm/etr.h>
-#include <asm/lowcore.h>
-#include <asm/cio.h>
-#include <asm/cpu.h>
-#include "s390mach.h"
-
-static struct semaphore m_sem;
-
-static NORET_TYPE void
-s390_handle_damage(char *msg)
-{
-#ifdef CONFIG_SMP
-	smp_send_stop();
-#endif
-	disabled_wait((unsigned long) __builtin_return_address(0));
-	for(;;);
-}
-
-static crw_handler_t crw_handlers[NR_RSCS];
-
-/**
- * s390_register_crw_handler() - register a channel report word handler
- * @rsc: reporting source code to handle
- * @handler: handler to be registered
- *
- * Returns %0 on success and a negative error value otherwise.
- */
-int s390_register_crw_handler(int rsc, crw_handler_t handler)
-{
-	if ((rsc < 0) || (rsc >= NR_RSCS))
-		return -EINVAL;
-	if (!cmpxchg(&crw_handlers[rsc], NULL, handler))
-		return 0;
-	return -EBUSY;
-}
-
-/**
- * s390_unregister_crw_handler() - unregister a channel report word handler
- * @rsc: reporting source code to handle
- */
-void s390_unregister_crw_handler(int rsc)
-{
-	if ((rsc < 0) || (rsc >= NR_RSCS))
-		return;
-	xchg(&crw_handlers[rsc], NULL);
-	synchronize_sched();
-}
-
-/*
- * Retrieve CRWs and call function to handle event.
- */
-static int s390_collect_crw_info(void *param)
-{
-	struct crw crw[2];
-	int ccode;
-	struct semaphore *sem;
-	unsigned int chain;
-	int ignore;
-
-	sem = (struct semaphore *)param;
-repeat:
-	ignore = down_interruptible(sem);
-	chain = 0;
-	while (1) {
-		if (unlikely(chain > 1)) {
-			struct crw tmp_crw;
-
-			printk(KERN_WARNING"%s: Code does not support more "
-			       "than two chained crws; please report to "
-			       "linux390@de.ibm.com!\n", __func__);
-			ccode = stcrw(&tmp_crw);
-			printk(KERN_WARNING"%s: crw reports slct=%d, oflw=%d, "
-			       "chn=%d, rsc=%X, anc=%d, erc=%X, rsid=%X\n",
-			       __func__, tmp_crw.slct, tmp_crw.oflw,
-			       tmp_crw.chn, tmp_crw.rsc, tmp_crw.anc,
-			       tmp_crw.erc, tmp_crw.rsid);
-			printk(KERN_WARNING"%s: This was crw number %x in the "
-			       "chain\n", __func__, chain);
-			if (ccode != 0)
-				break;
-			chain = tmp_crw.chn ? chain + 1 : 0;
-			continue;
-		}
-		ccode = stcrw(&crw[chain]);
-		if (ccode != 0)
-			break;
-		printk(KERN_DEBUG "crw_info : CRW reports slct=%d, oflw=%d, "
-		       "chn=%d, rsc=%X, anc=%d, erc=%X, rsid=%X\n",
-		       crw[chain].slct, crw[chain].oflw, crw[chain].chn,
-		       crw[chain].rsc, crw[chain].anc, crw[chain].erc,
-		       crw[chain].rsid);
-		/* Check for overflows. */
-		if (crw[chain].oflw) {
-			int i;
-
-			pr_debug("%s: crw overflow detected!\n", __func__);
-			for (i = 0; i < NR_RSCS; i++) {
-				if (crw_handlers[i])
-					crw_handlers[i](NULL, NULL, 1);
-			}
-			chain = 0;
-			continue;
-		}
-		if (crw[0].chn && !chain) {
-			chain++;
-			continue;
-		}
-		if (crw_handlers[crw[chain].rsc])
-			crw_handlers[crw[chain].rsc](&crw[0],
-						     chain ? &crw[1] : NULL,
-						     0);
-		/* chain is always 0 or 1 here. */
-		chain = crw[chain].chn ? chain + 1 : 0;
-	}
-	goto repeat;
-	return 0;
-}
-
-struct mcck_struct {
-	int kill_task;
-	int channel_report;
-	int warning;
-	unsigned long long mcck_code;
-};
-
-static DEFINE_PER_CPU(struct mcck_struct, cpu_mcck);
-
-/*
- * Main machine check handler function. Will be called with interrupts enabled
- * or disabled and machine checks enabled or disabled.
- */
-void
-s390_handle_mcck(void)
-{
-	unsigned long flags;
-	struct mcck_struct mcck;
-
-	/*
-	 * Disable machine checks and get the current state of accumulated
-	 * machine checks. Afterwards delete the old state and enable machine
-	 * checks again.
-	 */
-	local_irq_save(flags);
-	local_mcck_disable();
-	mcck = __get_cpu_var(cpu_mcck);
-	memset(&__get_cpu_var(cpu_mcck), 0, sizeof(struct mcck_struct));
-	clear_thread_flag(TIF_MCCK_PENDING);
-	local_mcck_enable();
-	local_irq_restore(flags);
-
-	if (mcck.channel_report)
-		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 (mcck.warning) {	/* 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_cad_pid(SIGPWR, 1);
-	}
-#endif
-
-	if (mcck.kill_task) {
-		local_irq_enable();
-		printk(KERN_EMERG "mcck: Terminating task because of machine "
-		       "malfunction (code 0x%016llx).\n", mcck.mcck_code);
-		printk(KERN_EMERG "mcck: task: %s, pid: %d.\n",
-		       current->comm, current->pid);
-		do_exit(SIGSEGV);
-	}
-}
-EXPORT_SYMBOL_GPL(s390_handle_mcck);
-
-/*
- * returns 0 if all registers could be validated
- * returns 1 otherwise
- */
-static int
-s390_revalidate_registers(struct mci *mci)
-{
-	int kill_task;
-	u64 tmpclock;
-	u64 zero;
-	void *fpt_save_area, *fpt_creg_save_area;
-
-	kill_task = 0;
-	zero = 0;
-	/* General purpose registers */
-	if (!mci->gr)
-		/*
-		 * General purpose registers couldn't be restored and have
-		 * unknown contents. Process needs to be terminated.
-		 */
-		kill_task = 1;
-
-	/* Revalidate floating point registers */
-	if (!mci->fp)
-		/*
-		 * Floating point registers can't be restored and
-		 * therefore the process needs to be terminated.
-		 */
-		kill_task = 1;
-
-#ifndef CONFIG_64BIT
-	asm volatile(
-		"	ld	0,0(%0)\n"
-		"	ld	2,8(%0)\n"
-		"	ld	4,16(%0)\n"
-		"	ld	6,24(%0)"
-		: : "a" (&S390_lowcore.floating_pt_save_area));
-#endif
-
-	if (MACHINE_HAS_IEEE) {
-#ifdef CONFIG_64BIT
-		fpt_save_area = &S390_lowcore.floating_pt_save_area;
-		fpt_creg_save_area = &S390_lowcore.fpt_creg_save_area;
-#else
-		fpt_save_area = (void *) S390_lowcore.extended_save_area_addr;
-		fpt_creg_save_area = fpt_save_area+128;
-#endif
-		/* Floating point control register */
-		if (!mci->fc) {
-			/*
-			 * Floating point control register can't be restored.
-			 * Task will be terminated.
-			 */
-			asm volatile("lfpc 0(%0)" : : "a" (&zero), "m" (zero));
-			kill_task = 1;
-
-		} else
-			asm volatile("lfpc 0(%0)" : : "a" (fpt_creg_save_area));
-
-		asm volatile(
-			"	ld	0,0(%0)\n"
-			"	ld	1,8(%0)\n"
-			"	ld	2,16(%0)\n"
-			"	ld	3,24(%0)\n"
-			"	ld	4,32(%0)\n"
-			"	ld	5,40(%0)\n"
-			"	ld	6,48(%0)\n"
-			"	ld	7,56(%0)\n"
-			"	ld	8,64(%0)\n"
-			"	ld	9,72(%0)\n"
-			"	ld	10,80(%0)\n"
-			"	ld	11,88(%0)\n"
-			"	ld	12,96(%0)\n"
-			"	ld	13,104(%0)\n"
-			"	ld	14,112(%0)\n"
-			"	ld	15,120(%0)\n"
-			: : "a" (fpt_save_area));
-	}
-
-	/* Revalidate access registers */
-	asm volatile(
-		"	lam	0,15,0(%0)"
-		: : "a" (&S390_lowcore.access_regs_save_area));
-	if (!mci->ar)
-		/*
-		 * Access registers have unknown contents.
-		 * Terminating task.
-		 */
-		kill_task = 1;
-
-	/* Revalidate control registers */
-	if (!mci->cr)
-		/*
-		 * Control registers have unknown contents.
-		 * Can't recover and therefore stopping machine.
-		 */
-		s390_handle_damage("invalid control registers.");
-	else
-#ifdef CONFIG_64BIT
-		asm volatile(
-			"	lctlg	0,15,0(%0)"
-			: : "a" (&S390_lowcore.cregs_save_area));
-#else
-		asm volatile(
-			"	lctl	0,15,0(%0)"
-			: : "a" (&S390_lowcore.cregs_save_area));
-#endif
-
-	/*
-	 * We don't even try to revalidate the TOD register, since we simply
-	 * can't write something sensible into that register.
-	 */
-
-#ifdef CONFIG_64BIT
-	/*
-	 * See if we can revalidate the TOD programmable register with its
-	 * old contents (should be zero) otherwise set it to zero.
-	 */
-	if (!mci->pr)
-		asm volatile(
-			"	sr	0,0\n"
-			"	sckpf"
-			: : : "0", "cc");
-	else
-		asm volatile(
-			"	l	0,0(%0)\n"
-			"	sckpf"
-			: : "a" (&S390_lowcore.tod_progreg_save_area)
-			: "0", "cc");
-#endif
-
-	/* Revalidate clock comparator register */
-	asm volatile(
-		"	stck	0(%1)\n"
-		"	sckc	0(%1)"
-		: "=m" (tmpclock) : "a" (&(tmpclock)) : "cc", "memory");
-
-	/* Check if old PSW is valid */
-	if (!mci->wp)
-		/*
-		 * Can't tell if we come from user or kernel mode
-		 * -> stopping machine.
-		 */
-		s390_handle_damage("old psw invalid.");
-
-	if (!mci->ms || !mci->pm || !mci->ia)
-		kill_task = 1;
-
-	return kill_task;
-}
-
-#define MAX_IPD_COUNT	29
-#define MAX_IPD_TIME	(5 * 60 * USEC_PER_SEC) /* 5 minutes */
-
-/*
- * machine check handler.
- */
-void notrace s390_do_machine_check(struct pt_regs *regs)
-{
-	static DEFINE_SPINLOCK(ipd_lock);
-	static unsigned long long last_ipd;
-	static int ipd_count;
-	unsigned long long tmp;
-	struct mci *mci;
-	struct mcck_struct *mcck;
-	int umode;
-
-	lockdep_off();
-
-	s390_idle_check();
-
-	mci = (struct mci *) &S390_lowcore.mcck_interruption_code;
-	mcck = &__get_cpu_var(cpu_mcck);
-	umode = user_mode(regs);
-
-	if (mci->sd)
-		/* System damage -> stopping machine */
-		s390_handle_damage("received system damage machine check.");
-
-	if (mci->pd) {
-		if (mci->b) {
-			/* Processing backup -> verify if we can survive this */
-			u64 z_mcic, o_mcic, t_mcic;
-#ifdef CONFIG_64BIT
-			z_mcic = (1ULL<<63 | 1ULL<<59 | 1ULL<<29);
-			o_mcic = (1ULL<<43 | 1ULL<<42 | 1ULL<<41 | 1ULL<<40 |
-				  1ULL<<36 | 1ULL<<35 | 1ULL<<34 | 1ULL<<32 |
-				  1ULL<<30 | 1ULL<<21 | 1ULL<<20 | 1ULL<<17 |
-				  1ULL<<16);
-#else
-			z_mcic = (1ULL<<63 | 1ULL<<59 | 1ULL<<57 | 1ULL<<50 |
-				  1ULL<<29);
-			o_mcic = (1ULL<<43 | 1ULL<<42 | 1ULL<<41 | 1ULL<<40 |
-				  1ULL<<36 | 1ULL<<35 | 1ULL<<34 | 1ULL<<32 |
-				  1ULL<<30 | 1ULL<<20 | 1ULL<<17 | 1ULL<<16);
-#endif
-			t_mcic = *(u64 *)mci;
-
-			if (((t_mcic & z_mcic) != 0) ||
-			    ((t_mcic & o_mcic) != o_mcic)) {
-				s390_handle_damage("processing backup machine "
-						   "check with damage.");
-			}
-
-			/*
-			 * Nullifying exigent condition, therefore we might
-			 * retry this instruction.
-			 */
-
-			spin_lock(&ipd_lock);
-
-			tmp = get_clock();
-
-			if (((tmp - last_ipd) >> 12) < MAX_IPD_TIME)
-				ipd_count++;
-			else
-				ipd_count = 1;
-
-			last_ipd = tmp;
-
-			if (ipd_count == MAX_IPD_COUNT)
-				s390_handle_damage("too many ipd retries.");
-
-			spin_unlock(&ipd_lock);
-		}
-		else {
-			/* Processing damage -> stopping machine */
-			s390_handle_damage("received instruction processing "
-					   "damage machine check.");
-		}
-	}
-	if (s390_revalidate_registers(mci)) {
-		if (umode) {
-			/*
-			 * Couldn't restore all register contents while in
-			 * user mode -> mark task for termination.
-			 */
-			mcck->kill_task = 1;
-			mcck->mcck_code = *(unsigned long long *) mci;
-			set_thread_flag(TIF_MCCK_PENDING);
-		}
-		else
-			/*
-			 * Couldn't restore all register contents while in
-			 * kernel mode -> stopping machine.
-			 */
-			s390_handle_damage("unable to revalidate registers.");
-	}
-
-	if (mci->cd) {
-		/* Timing facility damage */
-		s390_handle_damage("TOD clock damaged");
-	}
-
-	if (mci->ed && mci->ec) {
-		/* External damage */
-		if (S390_lowcore.external_damage_code & (1U << ED_ETR_SYNC))
-			etr_sync_check();
-		if (S390_lowcore.external_damage_code & (1U << ED_ETR_SWITCH))
-			etr_switch_to_local();
-		if (S390_lowcore.external_damage_code & (1U << ED_STP_SYNC))
-			stp_sync_check();
-		if (S390_lowcore.external_damage_code & (1U << ED_STP_ISLAND))
-			stp_island_check();
-	}
-
-	if (mci->se)
-		/* Storage error uncorrected */
-		s390_handle_damage("received storage error uncorrected "
-				   "machine check.");
-
-	if (mci->ke)
-		/* Storage key-error uncorrected */
-		s390_handle_damage("received storage key-error uncorrected "
-				   "machine check.");
-
-	if (mci->ds && mci->fa)
-		/* Storage degradation */
-		s390_handle_damage("received storage degradation machine "
-				   "check.");
-
-	if (mci->cp) {
-		/* Channel report word pending */
-		mcck->channel_report = 1;
-		set_thread_flag(TIF_MCCK_PENDING);
-	}
-
-	if (mci->w) {
-		/* Warning pending */
-		mcck->warning = 1;
-		set_thread_flag(TIF_MCCK_PENDING);
-	}
-	lockdep_on();
-}
-
-/*
- * s390_init_machine_check
- *
- * initialize machine check handling
- */
-static int
-machine_check_init(void)
-{
-	init_MUTEX_LOCKED(&m_sem);
-	ctl_set_bit(14, 25);	/* enable external damage 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)
-{
-	struct task_struct *task;
-
-	task = kthread_run(s390_collect_crw_info, &m_sem, "kmcheck");
-	if (IS_ERR(task))
-		return PTR_ERR(task);
-	ctl_set_bit(14, 28);	/* enable channel report MCH */
-	return 0;
-}
-
-device_initcall (machine_check_crw_init);