diff options
Diffstat (limited to 'drivers/s390/s390mach.c')
| -rw-r--r-- | drivers/s390/s390mach.c | 219 |
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); |