[S390] cio: introduce cio_commit_config
To change the configuration of a subchannel we alter the modifiable
bits of the subchannel's schib field and issue a modify subchannel.
There can be the case that not all changes were applied -or worse-
quietly overwritten by the hardware. With the next store subchannel
we obtain the current state of the hardware but lose our target
configuration.
With this patch we introduce a subchannel_config structure which
contains the target subchannel configuration. Additionally the msch
wrapper cio_modify is replaced with cio_commit_config which
copies the desired changes to a temporary schib. msch is then
called with the temporary schib. This schib is only written back
to the subchannel if all changes were applied.
Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
diff --git a/drivers/s390/cio/cio.c b/drivers/s390/cio/cio.c
index 9bdb463..8f1cec4 100644
--- a/drivers/s390/cio/cio.c
+++ b/drivers/s390/cio/cio.c
@@ -330,30 +330,70 @@
}
}
-/*
- * Function: cio_modify
- * Issues a "Modify Subchannel" on the specified subchannel
- */
-int
-cio_modify (struct subchannel *sch)
-{
- int ccode, retry, ret;
- ret = 0;
+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)
+{
+ struct schib schib;
+ int ccode, retry, ret = 0;
+
+ if (stsch(sch->schid, &schib) || !css_sch_is_valid(&schib))
+ return -ENODEV;
+
for (retry = 0; retry < 5; retry++) {
- ccode = msch_err (sch->schid, &sch->schib);
- if (ccode < 0) /* -EIO if msch gets a program check. */
+ /* copy desired changes to local schib */
+ cio_apply_config(sch, &schib);
+ ccode = msch_err(sch->schid, &schib);
+ if (ccode < 0) /* -EIO if msch gets a program check. */
return ccode;
switch (ccode) {
case 0: /* successfull */
- return 0;
- case 1: /* status pending */
+ 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 */
return -EBUSY;
- case 2: /* busy */
- udelay (100); /* allow for recovery */
+ case 2: /* busy */
+ udelay(100); /* allow for recovery */
ret = -EBUSY;
break;
- case 3: /* not operational */
+ case 3: /* not operational */
return -ENODEV;
}
}
@@ -396,32 +436,24 @@
if (cio_update_schib(sch))
return -ENODEV;
- for (retry = 5, ret = 0; retry > 0; retry--) {
- sch->schib.pmcw.ena = 1;
- sch->schib.pmcw.isc = sch->isc;
- sch->schib.pmcw.intparm = intparm;
- ret = cio_modify(sch);
- if (ret == -ENODEV)
- break;
- if (ret == -EIO)
+ sch->config.ena = 1;
+ sch->config.isc = sch->isc;
+ sch->config.intparm = intparm;
+
+ for (retry = 0; retry < 3; retry++) {
+ ret = cio_commit_config(sch);
+ if (ret == -EIO) {
/*
- * Got a program check in cio_modify. Try without
+ * Got a program check in msch. Try without
* the concurrent sense bit the next time.
*/
- sch->schib.pmcw.csense = 0;
- if (ret == 0) {
- if (cio_update_schib(sch)) {
- ret = -ENODEV;
- break;
- }
- if (sch->schib.pmcw.ena)
- break;
- }
- if (ret == -EBUSY) {
+ sch->config.csense = 0;
+ } else if (ret == -EBUSY) {
struct irb irb;
if (tsch(sch->schid, &irb) != 0)
break;
- }
+ } else
+ break;
}
sprintf (dbf_txt, "ret:%d", ret);
CIO_TRACE_EVENT (2, dbf_txt);
@@ -436,7 +468,6 @@
int cio_disable_subchannel(struct subchannel *sch)
{
char dbf_txt[15];
- int retry;
int ret;
CIO_TRACE_EVENT (2, "dissch");
@@ -454,27 +485,9 @@
*/
return -EBUSY;
- for (retry = 5, ret = 0; retry > 0; retry--) {
- sch->schib.pmcw.ena = 0;
- ret = cio_modify(sch);
- if (ret == -ENODEV)
- break;
- if (ret == -EBUSY)
- /*
- * The subchannel is busy or status pending.
- * We'll disable when the next interrupt was delivered
- * via the state machine.
- */
- break;
- if (ret == 0) {
- if (cio_update_schib(sch)) {
- ret = -ENODEV;
- break;
- }
- if (!sch->schib.pmcw.ena)
- break;
- }
- }
+ sch->config.ena = 0;
+ ret = cio_commit_config(sch);
+
sprintf (dbf_txt, "ret:%d", ret);
CIO_TRACE_EVENT (2, dbf_txt);
return ret;
@@ -817,10 +830,9 @@
* enable console I/O-interrupt subclass
*/
isc_register(CONSOLE_ISC);
- console_subchannel.schib.pmcw.isc = CONSOLE_ISC;
- console_subchannel.schib.pmcw.intparm =
- (u32)(addr_t)&console_subchannel;
- ret = cio_modify(&console_subchannel);
+ console_subchannel.config.isc = CONSOLE_ISC;
+ console_subchannel.config.intparm = (u32)(addr_t)&console_subchannel;
+ ret = cio_commit_config(&console_subchannel);
if (ret) {
isc_unregister(CONSOLE_ISC);
console_subchannel_in_use = 0;
@@ -832,8 +844,8 @@
void
cio_release_console(void)
{
- console_subchannel.schib.pmcw.intparm = 0;
- cio_modify(&console_subchannel);
+ console_subchannel.config.intparm = 0;
+ cio_commit_config(&console_subchannel);
isc_unregister(CONSOLE_ISC);
console_subchannel_in_use = 0;
}
diff --git a/drivers/s390/cio/cio.h b/drivers/s390/cio/cio.h
index fb125ef..5150fba 100644
--- a/drivers/s390/cio/cio.h
+++ b/drivers/s390/cio/cio.h
@@ -45,6 +45,19 @@
/* ... in an operand exception. */
} __attribute__ ((packed));
+/* Target SCHIB configuration. */
+struct schib_config {
+ u64 mba;
+ u32 intparm;
+ u16 mbi;
+ u32 isc:3;
+ u32 ena:1;
+ u32 mme:2;
+ u32 mp:1;
+ u32 csense:1;
+ u32 mbfc:1;
+} __attribute__ ((packed));
+
/*
* subchannel information block
*/
@@ -83,6 +96,7 @@
struct css_driver *driver;
void *private; /* private per subchannel type data */
struct work_struct work;
+ struct schib_config config;
} __attribute__ ((aligned(8)));
#define IO_INTERRUPT_TYPE 0 /* I/O interrupt type */
@@ -101,8 +115,8 @@
extern int cio_cancel (struct subchannel *);
extern int cio_set_options (struct subchannel *, int);
extern int cio_get_options (struct subchannel *);
-extern int cio_modify (struct subchannel *);
extern int cio_update_schib(struct subchannel *sch);
+extern int cio_commit_config(struct subchannel *sch);
int cio_tm_start_key(struct subchannel *sch, struct tcw *tcw, u8 lpm, u8 key);
int cio_tm_intrg(struct subchannel *sch);
diff --git a/drivers/s390/cio/cmf.c b/drivers/s390/cio/cmf.c
index 288482b..6ddd023 100644
--- a/drivers/s390/cio/cmf.c
+++ b/drivers/s390/cio/cmf.c
@@ -185,58 +185,19 @@
static int set_schib(struct ccw_device *cdev, u32 mme, int mbfc,
unsigned long address)
{
- int ret;
- int retry;
struct subchannel *sch;
- struct schib *schib;
sch = to_subchannel(cdev->dev.parent);
- schib = &sch->schib;
- /* msch can silently fail, so do it again if necessary */
- for (retry = 0; retry < 3; retry++) {
- /* prepare schib */
- if (cio_update_schib(sch))
- return -ENODEV;
- schib->pmcw.mme = mme;
- schib->pmcw.mbfc = mbfc;
- /* address can be either a block address or a block index */
- if (mbfc)
- schib->mba = address;
- else
- schib->pmcw.mbi = address;
- /* try to submit it */
- switch(ret = msch_err(sch->schid, schib)) {
- case 0:
- break;
- case 1:
- case 2: /* in I/O or status pending */
- ret = -EBUSY;
- break;
- case 3: /* subchannel is no longer valid */
- ret = -ENODEV;
- break;
- default: /* msch caught an exception */
- ret = -EINVAL;
- break;
- }
- if (cio_update_schib(sch))
- return -ENODEV;
+ sch->config.mme = mme;
+ sch->config.mbfc = mbfc;
+ /* address can be either a block address or a block index */
+ if (mbfc)
+ sch->config.mba = address;
+ else
+ sch->config.mbi = address;
- if (ret)
- break;
-
- /* check if it worked */
- if (schib->pmcw.mme == mme &&
- schib->pmcw.mbfc == mbfc &&
- (mbfc ? (schib->mba == address)
- : (schib->pmcw.mbi == address)))
- return 0;
-
- ret = -EINVAL;
- }
-
- return ret;
+ return cio_commit_config(sch);
}
struct set_schib_struct {
diff --git a/drivers/s390/cio/css.c b/drivers/s390/cio/css.c
index 76bbb1e..1b2d514 100644
--- a/drivers/s390/cio/css.c
+++ b/drivers/s390/cio/css.c
@@ -128,8 +128,8 @@
{
if (sch) {
/* Reset intparm to zeroes. */
- sch->schib.pmcw.intparm = 0;
- cio_modify(sch);
+ sch->config.intparm = 0;
+ cio_commit_config(sch);
kfree(sch->lock);
kfree(sch);
}
diff --git a/drivers/s390/cio/device.c b/drivers/s390/cio/device.c
index 51e9421..d312701 100644
--- a/drivers/s390/cio/device.c
+++ b/drivers/s390/cio/device.c
@@ -1020,8 +1020,8 @@
sch = to_subchannel(cdev->dev.parent);
css_sch_device_unregister(sch);
/* Reset intparm to zeroes. */
- sch->schib.pmcw.intparm = 0;
- cio_modify(sch);
+ sch->config.intparm = 0;
+ cio_commit_config(sch);
/* Release cdev reference for workqueue processing.*/
put_device(&cdev->dev);
/* Release subchannel reference for local processing. */
@@ -1148,8 +1148,8 @@
spin_unlock_irq(former_parent->lock);
css_sch_device_unregister(former_parent);
/* Reset intparm to zeroes. */
- former_parent->schib.pmcw.intparm = 0;
- cio_modify(former_parent);
+ former_parent->config.intparm = 0;
+ cio_commit_config(former_parent);
}
sch_attach_device(sch, cdev);
out:
@@ -1170,6 +1170,14 @@
dev_fsm_event(cdev, DEV_EVENT_INTERRUPT);
}
+void io_subchannel_init_config(struct subchannel *sch)
+{
+ memset(&sch->config, 0, sizeof(sch->config));
+ sch->config.csense = 1;
+ if ((sch->lpm & (sch->lpm - 1)) != 0)
+ sch->config.mp = 1;
+}
+
static void io_subchannel_init_fields(struct subchannel *sch)
{
if (cio_is_console(sch->schid))
@@ -1184,16 +1192,8 @@
sch->schib.pmcw.dev, sch->schid.ssid,
sch->schid.sch_no, sch->schib.pmcw.pim,
sch->schib.pmcw.pam, sch->schib.pmcw.pom);
- /* Initially set up some fields in the pmcw. */
- sch->schib.pmcw.ena = 0;
- sch->schib.pmcw.csense = 1; /* concurrent sense */
- if ((sch->lpm & (sch->lpm - 1)) != 0)
- sch->schib.pmcw.mp = 1; /* multipath mode */
- /* clean up possible residual cmf stuff */
- sch->schib.pmcw.mme = 0;
- sch->schib.pmcw.mbfc = 0;
- sch->schib.pmcw.mbi = 0;
- sch->schib.mba = 0;
+
+ io_subchannel_init_config(sch);
}
static void io_subchannel_do_unreg(struct work_struct *work)
@@ -1203,8 +1203,8 @@
sch = container_of(work, struct subchannel, work);
css_sch_device_unregister(sch);
/* Reset intparm to zeroes. */
- sch->schib.pmcw.intparm = 0;
- cio_modify(sch);
+ sch->config.intparm = 0;
+ cio_commit_config(sch);
put_device(&sch->dev);
}
@@ -1680,8 +1680,8 @@
spin_lock_irqsave(sch->lock, flags);
/* Reset intparm to zeroes. */
- sch->schib.pmcw.intparm = 0;
- cio_modify(sch);
+ sch->config.intparm = 0;
+ cio_commit_config(sch);
break;
case REPROBE:
ccw_device_trigger_reprobe(cdev);
diff --git a/drivers/s390/cio/device.h b/drivers/s390/cio/device.h
index 104ed66..0f2e63e 100644
--- a/drivers/s390/cio/device.h
+++ b/drivers/s390/cio/device.h
@@ -76,6 +76,7 @@
extern atomic_t ccw_device_init_count;
void io_subchannel_recog_done(struct ccw_device *cdev);
+void io_subchannel_init_config(struct subchannel *sch);
int ccw_device_cancel_halt_clear(struct ccw_device *);
diff --git a/drivers/s390/cio/device_fsm.c b/drivers/s390/cio/device_fsm.c
index e1a3786..9e24967 100644
--- a/drivers/s390/cio/device_fsm.c
+++ b/drivers/s390/cio/device_fsm.c
@@ -1026,11 +1026,12 @@
* we have before performing device selection :/
*/
sch->lpm = sch->schib.pmcw.pam & sch->opm;
- /* Re-set some bits in the pmcw that were lost. */
- sch->schib.pmcw.csense = 1;
- sch->schib.pmcw.ena = 0;
- if ((sch->lpm & (sch->lpm - 1)) != 0)
- sch->schib.pmcw.mp = 1;
+ /*
+ * Use the initial configuration since we can't be shure that the old
+ * paths are valid.
+ */
+ io_subchannel_init_config(sch);
+
/* We should also udate ssd info, but this has to wait. */
/* Check if this is another device which appeared on the same sch. */
if (sch->schib.pmcw.dev != cdev->private->dev_id.devno) {