diff options
Diffstat (limited to 'drivers/s390/cio/cio.c')
-rw-r--r-- | drivers/s390/cio/cio.c | 758 |
1 files changed, 758 insertions, 0 deletions
diff --git a/drivers/s390/cio/cio.c b/drivers/s390/cio/cio.c new file mode 100644 index 000000000..6d716db2a --- /dev/null +++ b/drivers/s390/cio/cio.c @@ -0,0 +1,758 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * S/390 common I/O routines -- low level i/o calls + * + * Copyright IBM Corp. 1999, 2008 + * Author(s): Ingo Adlung (adlung@de.ibm.com) + * Cornelia Huck (cornelia.huck@de.ibm.com) + * Arnd Bergmann (arndb@de.ibm.com) + * Martin Schwidefsky (schwidefsky@de.ibm.com) + */ + +#define KMSG_COMPONENT "cio" +#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt + +#include <linux/ftrace.h> +#include <linux/module.h> +#include <linux/init.h> +#include <linux/slab.h> +#include <linux/device.h> +#include <linux/kernel_stat.h> +#include <linux/interrupt.h> +#include <linux/irq.h> +#include <asm/cio.h> +#include <asm/delay.h> +#include <asm/irq.h> +#include <asm/irq_regs.h> +#include <asm/setup.h> +#include <asm/ipl.h> +#include <asm/chpid.h> +#include <asm/airq.h> +#include <asm/isc.h> +#include <linux/sched/cputime.h> +#include <asm/fcx.h> +#include <asm/nmi.h> +#include <asm/crw.h> +#include "cio.h" +#include "css.h" +#include "chsc.h" +#include "ioasm.h" +#include "io_sch.h" +#include "blacklist.h" +#include "cio_debug.h" +#include "chp.h" +#include "trace.h" + +debug_info_t *cio_debug_msg_id; +debug_info_t *cio_debug_trace_id; +debug_info_t *cio_debug_crw_id; + +DEFINE_PER_CPU_ALIGNED(struct irb, cio_irb); +EXPORT_PER_CPU_SYMBOL(cio_irb); + +/* + * Function: cio_debug_init + * Initializes three debug logs for common I/O: + * - cio_msg logs generic cio messages + * - cio_trace logs the calling of different functions + * - cio_crw logs machine check related cio messages + */ +static int __init cio_debug_init(void) +{ + cio_debug_msg_id = debug_register("cio_msg", 16, 1, 11 * sizeof(long)); + if (!cio_debug_msg_id) + goto out_unregister; + debug_register_view(cio_debug_msg_id, &debug_sprintf_view); + debug_set_level(cio_debug_msg_id, 2); + cio_debug_trace_id = debug_register("cio_trace", 16, 1, 16); + if (!cio_debug_trace_id) + goto out_unregister; + debug_register_view(cio_debug_trace_id, &debug_hex_ascii_view); + debug_set_level(cio_debug_trace_id, 2); + cio_debug_crw_id = debug_register("cio_crw", 8, 1, 8 * sizeof(long)); + if (!cio_debug_crw_id) + goto out_unregister; + debug_register_view(cio_debug_crw_id, &debug_sprintf_view); + debug_set_level(cio_debug_crw_id, 4); + return 0; + +out_unregister: + debug_unregister(cio_debug_msg_id); + debug_unregister(cio_debug_trace_id); + debug_unregister(cio_debug_crw_id); + return -1; +} + +arch_initcall (cio_debug_init); + +int cio_set_options(struct subchannel *sch, int flags) +{ + struct io_subchannel_private *priv = to_io_private(sch); + + priv->options.suspend = (flags & DOIO_ALLOW_SUSPEND) != 0; + priv->options.prefetch = (flags & DOIO_DENY_PREFETCH) != 0; + priv->options.inter = (flags & DOIO_SUPPRESS_INTER) != 0; + return 0; +} + +static int +cio_start_handle_notoper(struct subchannel *sch, __u8 lpm) +{ + char dbf_text[15]; + + if (lpm != 0) + sch->lpm &= ~lpm; + else + sch->lpm = 0; + + CIO_MSG_EVENT(2, "cio_start: 'not oper' status for " + "subchannel 0.%x.%04x!\n", sch->schid.ssid, + sch->schid.sch_no); + + if (cio_update_schib(sch)) + return -ENODEV; + + sprintf(dbf_text, "no%s", dev_name(&sch->dev)); + CIO_TRACE_EVENT(0, dbf_text); + CIO_HEX_EVENT(0, &sch->schib, sizeof (struct schib)); + + return (sch->lpm ? -EACCES : -ENODEV); +} + +int +cio_start_key (struct subchannel *sch, /* subchannel structure */ + struct ccw1 * cpa, /* logical channel prog addr */ + __u8 lpm, /* logical path mask */ + __u8 key) /* storage key */ +{ + struct io_subchannel_private *priv = to_io_private(sch); + union orb *orb = &priv->orb; + int ccode; + + CIO_TRACE_EVENT(5, "stIO"); + CIO_TRACE_EVENT(5, dev_name(&sch->dev)); + + memset(orb, 0, sizeof(union orb)); + /* sch is always under 2G. */ + orb->cmd.intparm = (u32)(addr_t)sch; + orb->cmd.fmt = 1; + + orb->cmd.pfch = priv->options.prefetch == 0; + orb->cmd.spnd = priv->options.suspend; + orb->cmd.ssic = priv->options.suspend && priv->options.inter; + orb->cmd.lpm = (lpm != 0) ? lpm : sch->lpm; + /* + * for 64 bit we always support 64 bit IDAWs with 4k page size only + */ + orb->cmd.c64 = 1; + orb->cmd.i2k = 0; + orb->cmd.key = key >> 4; + /* issue "Start Subchannel" */ + orb->cmd.cpa = (__u32) __pa(cpa); + ccode = ssch(sch->schid, orb); + + /* process condition code */ + CIO_HEX_EVENT(5, &ccode, sizeof(ccode)); + + switch (ccode) { + case 0: + /* + * initialize device status information + */ + sch->schib.scsw.cmd.actl |= SCSW_ACTL_START_PEND; + return 0; + case 1: /* status pending */ + case 2: /* busy */ + return -EBUSY; + case 3: /* device/path not operational */ + return cio_start_handle_notoper(sch, lpm); + default: + return ccode; + } +} +EXPORT_SYMBOL_GPL(cio_start_key); + +int +cio_start (struct subchannel *sch, struct ccw1 *cpa, __u8 lpm) +{ + return cio_start_key(sch, cpa, lpm, PAGE_DEFAULT_KEY); +} +EXPORT_SYMBOL_GPL(cio_start); + +/* + * resume suspended I/O operation + */ +int +cio_resume (struct subchannel *sch) +{ + int ccode; + + CIO_TRACE_EVENT(4, "resIO"); + CIO_TRACE_EVENT(4, dev_name(&sch->dev)); + + ccode = rsch (sch->schid); + + CIO_HEX_EVENT(4, &ccode, sizeof(ccode)); + + switch (ccode) { + case 0: + sch->schib.scsw.cmd.actl |= SCSW_ACTL_RESUME_PEND; + return 0; + case 1: + return -EBUSY; + case 2: + return -EINVAL; + default: + /* + * useless to wait for request completion + * as device is no longer operational ! + */ + return -ENODEV; + } +} +EXPORT_SYMBOL_GPL(cio_resume); + +/* + * halt I/O operation + */ +int +cio_halt(struct subchannel *sch) +{ + int ccode; + + if (!sch) + return -ENODEV; + + CIO_TRACE_EVENT(2, "haltIO"); + CIO_TRACE_EVENT(2, dev_name(&sch->dev)); + + /* + * Issue "Halt subchannel" and process condition code + */ + ccode = hsch (sch->schid); + + CIO_HEX_EVENT(2, &ccode, sizeof(ccode)); + + switch (ccode) { + case 0: + sch->schib.scsw.cmd.actl |= SCSW_ACTL_HALT_PEND; + return 0; + case 1: /* status pending */ + case 2: /* busy */ + return -EBUSY; + default: /* device not operational */ + return -ENODEV; + } +} +EXPORT_SYMBOL_GPL(cio_halt); + +/* + * Clear I/O operation + */ +int +cio_clear(struct subchannel *sch) +{ + int ccode; + + if (!sch) + return -ENODEV; + + CIO_TRACE_EVENT(2, "clearIO"); + CIO_TRACE_EVENT(2, dev_name(&sch->dev)); + + /* + * Issue "Clear subchannel" and process condition code + */ + ccode = csch (sch->schid); + + CIO_HEX_EVENT(2, &ccode, sizeof(ccode)); + + switch (ccode) { + case 0: + sch->schib.scsw.cmd.actl |= SCSW_ACTL_CLEAR_PEND; + return 0; + default: /* device not operational */ + return -ENODEV; + } +} +EXPORT_SYMBOL_GPL(cio_clear); + +/* + * Function: cio_cancel + * Issues a "Cancel Subchannel" on the specified subchannel + * Note: We don't need any fancy intparms and flags here + * since xsch is executed synchronously. + * Only for common I/O internal use as for now. + */ +int +cio_cancel (struct subchannel *sch) +{ + int ccode; + + if (!sch) + return -ENODEV; + + CIO_TRACE_EVENT(2, "cancelIO"); + CIO_TRACE_EVENT(2, dev_name(&sch->dev)); + + ccode = xsch (sch->schid); + + CIO_HEX_EVENT(2, &ccode, sizeof(ccode)); + + switch (ccode) { + case 0: /* success */ + /* Update information in scsw. */ + if (cio_update_schib(sch)) + return -ENODEV; + return 0; + case 1: /* status pending */ + return -EBUSY; + case 2: /* not applicable */ + return -EINVAL; + default: /* not oper */ + return -ENODEV; + } +} +EXPORT_SYMBOL_GPL(cio_cancel); + +/** + * cio_cancel_halt_clear - Cancel running I/O by performing cancel, halt + * and clear ordinally if subchannel is valid. + * @sch: subchannel on which to perform the cancel_halt_clear operation + * @iretry: the number of the times remained to retry the next operation + * + * This should be called repeatedly since halt/clear are asynchronous + * operations. We do one try with cio_cancel, three tries with cio_halt, + * 255 tries with cio_clear. The caller should initialize @iretry with + * the value 255 for its first call to this, and keep using the same + * @iretry in the subsequent calls until it gets a non -EBUSY return. + * + * Returns 0 if device now idle, -ENODEV for device not operational, + * -EBUSY if an interrupt is expected (either from halt/clear or from a + * status pending), and -EIO if out of retries. + */ +int cio_cancel_halt_clear(struct subchannel *sch, int *iretry) +{ + int ret; + + if (cio_update_schib(sch)) + return -ENODEV; + if (!sch->schib.pmcw.ena) + /* Not operational -> done. */ + return 0; + /* Stage 1: cancel io. */ + if (!(scsw_actl(&sch->schib.scsw) & SCSW_ACTL_HALT_PEND) && + !(scsw_actl(&sch->schib.scsw) & SCSW_ACTL_CLEAR_PEND)) { + if (!scsw_is_tm(&sch->schib.scsw)) { + ret = cio_cancel(sch); + if (ret != -EINVAL) + return ret; + } + /* + * Cancel io unsuccessful or not applicable (transport mode). + * Continue with asynchronous instructions. + */ + *iretry = 3; /* 3 halt retries. */ + } + /* Stage 2: halt io. */ + if (!(scsw_actl(&sch->schib.scsw) & SCSW_ACTL_CLEAR_PEND)) { + if (*iretry) { + *iretry -= 1; + ret = cio_halt(sch); + if (ret != -EBUSY) + return (ret == 0) ? -EBUSY : ret; + } + /* Halt io unsuccessful. */ + *iretry = 255; /* 255 clear retries. */ + } + /* Stage 3: clear io. */ + if (*iretry) { + *iretry -= 1; + ret = cio_clear(sch); + return (ret == 0) ? -EBUSY : ret; + } + /* Function was unsuccessful */ + return -EIO; +} +EXPORT_SYMBOL_GPL(cio_cancel_halt_clear); + +static void cio_apply_config(struct subchannel *sch, struct schib *schib) +{ + schib->pmcw.intparm = sch->config.intparm; + schib->pmcw.mbi = sch->config.mbi; + schib->pmcw.isc = sch->config.isc; + schib->pmcw.ena = sch->config.ena; + schib->pmcw.mme = sch->config.mme; + schib->pmcw.mp = sch->config.mp; + schib->pmcw.csense = sch->config.csense; + schib->pmcw.mbfc = sch->config.mbfc; + if (sch->config.mbfc) + schib->mba = sch->config.mba; +} + +static int cio_check_config(struct subchannel *sch, struct schib *schib) +{ + return (schib->pmcw.intparm == sch->config.intparm) && + (schib->pmcw.mbi == sch->config.mbi) && + (schib->pmcw.isc == sch->config.isc) && + (schib->pmcw.ena == sch->config.ena) && + (schib->pmcw.mme == sch->config.mme) && + (schib->pmcw.mp == sch->config.mp) && + (schib->pmcw.csense == sch->config.csense) && + (schib->pmcw.mbfc == sch->config.mbfc) && + (!sch->config.mbfc || (schib->mba == sch->config.mba)); +} + +/* + * cio_commit_config - apply configuration to the subchannel + */ +int cio_commit_config(struct subchannel *sch) +{ + int ccode, retry, ret = 0; + struct schib schib; + struct irb irb; + + if (stsch(sch->schid, &schib) || !css_sch_is_valid(&schib)) + return -ENODEV; + + for (retry = 0; retry < 5; retry++) { + /* copy desired changes to local schib */ + cio_apply_config(sch, &schib); + ccode = msch(sch->schid, &schib); + if (ccode < 0) /* -EIO if msch gets a program check. */ + return ccode; + switch (ccode) { + case 0: /* successful */ + if (stsch(sch->schid, &schib) || + !css_sch_is_valid(&schib)) + return -ENODEV; + if (cio_check_config(sch, &schib)) { + /* commit changes from local schib */ + memcpy(&sch->schib, &schib, sizeof(schib)); + return 0; + } + ret = -EAGAIN; + break; + case 1: /* status pending */ + ret = -EBUSY; + if (tsch(sch->schid, &irb)) + return ret; + break; + case 2: /* busy */ + udelay(100); /* allow for recovery */ + ret = -EBUSY; + break; + case 3: /* not operational */ + return -ENODEV; + } + } + return ret; +} +EXPORT_SYMBOL_GPL(cio_commit_config); + +/** + * cio_update_schib - Perform stsch and update schib if subchannel is valid. + * @sch: subchannel on which to perform stsch + * Return zero on success, -ENODEV otherwise. + */ +int cio_update_schib(struct subchannel *sch) +{ + struct schib schib; + + if (stsch(sch->schid, &schib) || !css_sch_is_valid(&schib)) + return -ENODEV; + + memcpy(&sch->schib, &schib, sizeof(schib)); + return 0; +} +EXPORT_SYMBOL_GPL(cio_update_schib); + +/** + * cio_enable_subchannel - enable a subchannel. + * @sch: subchannel to be enabled + * @intparm: interruption parameter to set + */ +int cio_enable_subchannel(struct subchannel *sch, u32 intparm) +{ + int ret; + + CIO_TRACE_EVENT(2, "ensch"); + CIO_TRACE_EVENT(2, dev_name(&sch->dev)); + + if (sch_is_pseudo_sch(sch)) + return -EINVAL; + if (cio_update_schib(sch)) + return -ENODEV; + + sch->config.ena = 1; + sch->config.isc = sch->isc; + sch->config.intparm = intparm; + + ret = cio_commit_config(sch); + if (ret == -EIO) { + /* + * Got a program check in msch. Try without + * the concurrent sense bit the next time. + */ + sch->config.csense = 0; + ret = cio_commit_config(sch); + } + CIO_HEX_EVENT(2, &ret, sizeof(ret)); + return ret; +} +EXPORT_SYMBOL_GPL(cio_enable_subchannel); + +/** + * cio_disable_subchannel - disable a subchannel. + * @sch: subchannel to disable + */ +int cio_disable_subchannel(struct subchannel *sch) +{ + int ret; + + CIO_TRACE_EVENT(2, "dissch"); + CIO_TRACE_EVENT(2, dev_name(&sch->dev)); + + if (sch_is_pseudo_sch(sch)) + return 0; + if (cio_update_schib(sch)) + return -ENODEV; + + sch->config.ena = 0; + ret = cio_commit_config(sch); + + CIO_HEX_EVENT(2, &ret, sizeof(ret)); + return ret; +} +EXPORT_SYMBOL_GPL(cio_disable_subchannel); + +/* + * do_cio_interrupt() handles all normal I/O device IRQ's + */ +static irqreturn_t do_cio_interrupt(int irq, void *dummy) +{ + struct tpi_info *tpi_info; + struct subchannel *sch; + struct irb *irb; + + set_cpu_flag(CIF_NOHZ_DELAY); + tpi_info = (struct tpi_info *) &get_irq_regs()->int_code; + trace_s390_cio_interrupt(tpi_info); + irb = this_cpu_ptr(&cio_irb); + sch = (struct subchannel *)(unsigned long) tpi_info->intparm; + if (!sch) { + /* Clear pending interrupt condition. */ + inc_irq_stat(IRQIO_CIO); + tsch(tpi_info->schid, irb); + return IRQ_HANDLED; + } + spin_lock(sch->lock); + /* Store interrupt response block to lowcore. */ + if (tsch(tpi_info->schid, irb) == 0) { + /* Keep subchannel information word up to date. */ + memcpy (&sch->schib.scsw, &irb->scsw, sizeof (irb->scsw)); + /* Call interrupt handler if there is one. */ + if (sch->driver && sch->driver->irq) + sch->driver->irq(sch); + else + inc_irq_stat(IRQIO_CIO); + } else + inc_irq_stat(IRQIO_CIO); + spin_unlock(sch->lock); + + return IRQ_HANDLED; +} + +void __init init_cio_interrupts(void) +{ + irq_set_chip_and_handler(IO_INTERRUPT, + &dummy_irq_chip, handle_percpu_irq); + if (request_irq(IO_INTERRUPT, do_cio_interrupt, 0, "I/O", NULL)) + panic("Failed to register I/O interrupt\n"); +} + +#ifdef CONFIG_CCW_CONSOLE +static struct subchannel *console_sch; +static struct lock_class_key console_sch_key; + +/* + * Use cio_tsch to update the subchannel status and call the interrupt handler + * if status had been pending. Called with the subchannel's lock held. + */ +void cio_tsch(struct subchannel *sch) +{ + struct irb *irb; + int irq_context; + + irb = this_cpu_ptr(&cio_irb); + /* Store interrupt response block to lowcore. */ + if (tsch(sch->schid, irb) != 0) + /* Not status pending or not operational. */ + return; + memcpy(&sch->schib.scsw, &irb->scsw, sizeof(union scsw)); + /* Call interrupt handler with updated status. */ + irq_context = in_interrupt(); + if (!irq_context) { + local_bh_disable(); + irq_enter(); + } + kstat_incr_irq_this_cpu(IO_INTERRUPT); + if (sch->driver && sch->driver->irq) + sch->driver->irq(sch); + else + inc_irq_stat(IRQIO_CIO); + if (!irq_context) { + irq_exit(); + _local_bh_enable(); + } +} + +static int cio_test_for_console(struct subchannel_id schid, void *data) +{ + struct schib schib; + + if (stsch(schid, &schib) != 0) + return -ENXIO; + if ((schib.pmcw.st == SUBCHANNEL_TYPE_IO) && schib.pmcw.dnv && + (schib.pmcw.dev == console_devno)) { + console_irq = schid.sch_no; + return 1; /* found */ + } + return 0; +} + +static int cio_get_console_sch_no(void) +{ + struct subchannel_id schid; + struct schib schib; + + init_subchannel_id(&schid); + if (console_irq != -1) { + /* VM provided us with the irq number of the console. */ + schid.sch_no = console_irq; + if (stsch(schid, &schib) != 0 || + (schib.pmcw.st != SUBCHANNEL_TYPE_IO) || !schib.pmcw.dnv) + return -1; + console_devno = schib.pmcw.dev; + } else if (console_devno != -1) { + /* At least the console device number is known. */ + for_each_subchannel(cio_test_for_console, NULL); + } + return console_irq; +} + +struct subchannel *cio_probe_console(void) +{ + struct subchannel_id schid; + struct subchannel *sch; + struct schib schib; + int sch_no, ret; + + sch_no = cio_get_console_sch_no(); + if (sch_no == -1) { + pr_warn("No CCW console was found\n"); + return ERR_PTR(-ENODEV); + } + init_subchannel_id(&schid); + schid.sch_no = sch_no; + ret = stsch(schid, &schib); + if (ret) + return ERR_PTR(-ENODEV); + + sch = css_alloc_subchannel(schid, &schib); + if (IS_ERR(sch)) + return sch; + + lockdep_set_class(sch->lock, &console_sch_key); + isc_register(CONSOLE_ISC); + sch->config.isc = CONSOLE_ISC; + sch->config.intparm = (u32)(addr_t)sch; + ret = cio_commit_config(sch); + if (ret) { + isc_unregister(CONSOLE_ISC); + put_device(&sch->dev); + return ERR_PTR(ret); + } + console_sch = sch; + return sch; +} + +int cio_is_console(struct subchannel_id schid) +{ + if (!console_sch) + return 0; + return schid_equal(&schid, &console_sch->schid); +} + +void cio_register_early_subchannels(void) +{ + int ret; + + if (!console_sch) + return; + + ret = css_register_subchannel(console_sch); + if (ret) + put_device(&console_sch->dev); +} +#endif /* CONFIG_CCW_CONSOLE */ + +/** + * cio_tm_start_key - perform start function + * @sch: subchannel on which to perform the start function + * @tcw: transport-command word to be started + * @lpm: mask of paths to use + * @key: storage key to use for storage access + * + * Start the tcw on the given subchannel. Return zero on success, non-zero + * otherwise. + */ +int cio_tm_start_key(struct subchannel *sch, struct tcw *tcw, u8 lpm, u8 key) +{ + int cc; + union orb *orb = &to_io_private(sch)->orb; + + memset(orb, 0, sizeof(union orb)); + orb->tm.intparm = (u32) (addr_t) sch; + orb->tm.key = key >> 4; + orb->tm.b = 1; + orb->tm.lpm = lpm ? lpm : sch->lpm; + orb->tm.tcw = (u32) (addr_t) tcw; + cc = ssch(sch->schid, orb); + switch (cc) { + case 0: + return 0; + case 1: + case 2: + return -EBUSY; + default: + return cio_start_handle_notoper(sch, lpm); + } +} +EXPORT_SYMBOL_GPL(cio_tm_start_key); + +/** + * cio_tm_intrg - perform interrogate function + * @sch: subchannel on which to perform the interrogate function + * + * If the specified subchannel is running in transport-mode, perform the + * interrogate function. Return zero on success, non-zero otherwie. + */ +int cio_tm_intrg(struct subchannel *sch) +{ + int cc; + + if (!to_io_private(sch)->orb.tm.b) + return -EINVAL; + cc = xsch(sch->schid); + switch (cc) { + case 0: + case 2: + return 0; + case 1: + return -EBUSY; + default: + return -ENODEV; + } +} +EXPORT_SYMBOL_GPL(cio_tm_intrg); |