// 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 ([email protected])
* Cornelia Huck ([email protected])
* Arnd Bergmann ([email protected])
* Martin Schwidefsky ([email protected])
*/
#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)virt_to_phys(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 = virt_to_dma32(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;
tpi_info = &get_irq_regs()->tpi_info;
trace_s390_cio_interrupt(tpi_info);
irb = this_cpu_ptr(&cio_irb);
if (!tpi_info->intparm) {
/* Clear pending interrupt condition. */
inc_irq_stat(IRQIO_CIO);
tsch(tpi_info->schid, irb);
return IRQ_HANDLED;
}
sch = phys_to_virt(tpi_info->intparm);
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)virt_to_phys(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)virt_to_phys(sch);
orb->tm.key = key >> 4;
orb->tm.b = 1;
orb->tm.lpm = lpm ? lpm : sch->lpm;
orb->tm.tcw = virt_to_dma32(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);
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