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path: root/drivers/s390/cio/device_pgid.c
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Diffstat (limited to 'drivers/s390/cio/device_pgid.c')
-rw-r--r--drivers/s390/cio/device_pgid.c149
1 files changed, 120 insertions, 29 deletions
diff --git a/drivers/s390/cio/device_pgid.c b/drivers/s390/cio/device_pgid.c
index 54cb64ed078..1693a102dcf 100644
--- a/drivers/s390/cio/device_pgid.c
+++ b/drivers/s390/cio/device_pgid.c
@@ -24,6 +24,21 @@
#include "ioasm.h"
/*
+ * Helper function called from interrupt context to decide whether an
+ * operation should be tried again.
+ */
+static int __ccw_device_should_retry(struct scsw *scsw)
+{
+ /* CC is only valid if start function bit is set. */
+ if ((scsw->fctl & SCSW_FCTL_START_FUNC) && scsw->cc == 1)
+ return 1;
+ /* No more activity. For sense and set PGID we stubbornly try again. */
+ if (!scsw->actl)
+ return 1;
+ return 0;
+}
+
+/*
* Start Sense Path Group ID helper function. Used in ccw_device_recog
* and ccw_device_sense_pgid.
*/
@@ -33,12 +48,17 @@ __ccw_device_sense_pgid_start(struct ccw_device *cdev)
struct subchannel *sch;
struct ccw1 *ccw;
int ret;
+ int i;
sch = to_subchannel(cdev->dev.parent);
+ /* Return if we already checked on all paths. */
+ if (cdev->private->imask == 0)
+ return (sch->lpm == 0) ? -ENODEV : -EACCES;
+ i = 8 - ffs(cdev->private->imask);
+
/* Setup sense path group id channel program. */
ccw = cdev->private->iccws;
ccw->cmd_code = CCW_CMD_SENSE_PGID;
- ccw->cda = (__u32) __pa (&cdev->private->pgid);
ccw->count = sizeof (struct pgid);
ccw->flags = CCW_FLAG_SLI;
@@ -48,6 +68,7 @@ __ccw_device_sense_pgid_start(struct ccw_device *cdev)
ret = -ENODEV;
while (cdev->private->imask != 0) {
/* Try every path multiple times. */
+ ccw->cda = (__u32) __pa (&cdev->private->pgid[i]);
if (cdev->private->iretry > 0) {
cdev->private->iretry--;
ret = cio_start (sch, cdev->private->iccws,
@@ -64,7 +85,9 @@ __ccw_device_sense_pgid_start(struct ccw_device *cdev)
}
cdev->private->imask >>= 1;
cdev->private->iretry = 5;
+ i++;
}
+
return ret;
}
@@ -76,7 +99,7 @@ ccw_device_sense_pgid_start(struct ccw_device *cdev)
cdev->private->state = DEV_STATE_SENSE_PGID;
cdev->private->imask = 0x80;
cdev->private->iretry = 5;
- memset (&cdev->private->pgid, 0, sizeof (struct pgid));
+ memset (&cdev->private->pgid, 0, sizeof (cdev->private->pgid));
ret = __ccw_device_sense_pgid_start(cdev);
if (ret && ret != -EBUSY)
ccw_device_sense_pgid_done(cdev, ret);
@@ -91,6 +114,7 @@ __ccw_device_check_sense_pgid(struct ccw_device *cdev)
{
struct subchannel *sch;
struct irb *irb;
+ int i;
sch = to_subchannel(cdev->dev.parent);
irb = &cdev->private->irb;
@@ -124,7 +148,8 @@ __ccw_device_check_sense_pgid(struct ccw_device *cdev)
sch->schid.sch_no, sch->orb.lpm);
return -EACCES;
}
- if (cdev->private->pgid.inf.ps.state2 == SNID_STATE2_RESVD_ELSE) {
+ i = 8 - ffs(cdev->private->imask);
+ if (cdev->private->pgid[i].inf.ps.state2 == SNID_STATE2_RESVD_ELSE) {
CIO_MSG_EVENT(2, "SNID - Device %04x on Subchannel 0.%x.%04x "
"is reserved by someone else\n",
cdev->private->devno, sch->schid.ssid,
@@ -145,10 +170,10 @@ ccw_device_sense_pgid_irq(struct ccw_device *cdev, enum dev_event dev_event)
int ret;
irb = (struct irb *) __LC_IRB;
- /* Retry sense pgid for cc=1. */
+
if (irb->scsw.stctl ==
(SCSW_STCTL_STATUS_PEND | SCSW_STCTL_ALERT_STATUS)) {
- if (irb->scsw.cc == 1) {
+ if (__ccw_device_should_retry(&irb->scsw)) {
ret = __ccw_device_sense_pgid_start(cdev);
if (ret && ret != -EBUSY)
ccw_device_sense_pgid_done(cdev, ret);
@@ -162,12 +187,6 @@ ccw_device_sense_pgid_irq(struct ccw_device *cdev, enum dev_event dev_event)
memset(&cdev->private->irb, 0, sizeof(struct irb));
switch (ret) {
/* 0, -ETIME, -EOPNOTSUPP, -EAGAIN, -EACCES or -EUSERS */
- case 0: /* Sense Path Group ID successful. */
- if (cdev->private->pgid.inf.ps.state1 == SNID_STATE1_RESET)
- memcpy(&cdev->private->pgid, &css[0]->global_pgid,
- sizeof(struct pgid));
- ccw_device_sense_pgid_done(cdev, 0);
- break;
case -EOPNOTSUPP: /* Sense Path Group ID not supported */
ccw_device_sense_pgid_done(cdev, -EOPNOTSUPP);
break;
@@ -176,13 +195,15 @@ ccw_device_sense_pgid_irq(struct ccw_device *cdev, enum dev_event dev_event)
break;
case -EACCES: /* channel is not operational. */
sch->lpm &= ~cdev->private->imask;
+ /* Fall through. */
+ case 0: /* Sense Path Group ID successful. */
cdev->private->imask >>= 1;
cdev->private->iretry = 5;
/* Fall through. */
case -EAGAIN: /* Try again. */
ret = __ccw_device_sense_pgid_start(cdev);
if (ret != 0 && ret != -EBUSY)
- ccw_device_sense_pgid_done(cdev, -ENODEV);
+ ccw_device_sense_pgid_done(cdev, ret);
break;
case -EUSERS: /* device is reserved for someone else. */
ccw_device_sense_pgid_done(cdev, -EUSERS);
@@ -203,20 +224,20 @@ __ccw_device_do_pgid(struct ccw_device *cdev, __u8 func)
sch = to_subchannel(cdev->dev.parent);
/* Setup sense path group id channel program. */
- cdev->private->pgid.inf.fc = func;
+ cdev->private->pgid[0].inf.fc = func;
ccw = cdev->private->iccws;
if (!cdev->private->flags.pgid_single) {
- cdev->private->pgid.inf.fc |= SPID_FUNC_MULTI_PATH;
+ cdev->private->pgid[0].inf.fc |= SPID_FUNC_MULTI_PATH;
ccw->cmd_code = CCW_CMD_SUSPEND_RECONN;
ccw->cda = 0;
ccw->count = 0;
ccw->flags = CCW_FLAG_SLI | CCW_FLAG_CC;
ccw++;
} else
- cdev->private->pgid.inf.fc |= SPID_FUNC_SINGLE_PATH;
+ cdev->private->pgid[0].inf.fc |= SPID_FUNC_SINGLE_PATH;
ccw->cmd_code = CCW_CMD_SET_PGID;
- ccw->cda = (__u32) __pa (&cdev->private->pgid);
+ ccw->cda = (__u32) __pa (&cdev->private->pgid[0]);
ccw->count = sizeof (struct pgid);
ccw->flags = CCW_FLAG_SLI;
@@ -244,6 +265,48 @@ __ccw_device_do_pgid(struct ccw_device *cdev, __u8 func)
}
/*
+ * Helper function to send a nop ccw down a path.
+ */
+static int __ccw_device_do_nop(struct ccw_device *cdev)
+{
+ struct subchannel *sch;
+ struct ccw1 *ccw;
+ int ret;
+
+ sch = to_subchannel(cdev->dev.parent);
+
+ /* Setup nop channel program. */
+ ccw = cdev->private->iccws;
+ ccw->cmd_code = CCW_CMD_NOOP;
+ ccw->cda = 0;
+ ccw->count = 0;
+ ccw->flags = CCW_FLAG_SLI;
+
+ /* Reset device status. */
+ memset(&cdev->private->irb, 0, sizeof(struct irb));
+
+ /* Try multiple times. */
+ ret = -ENODEV;
+ if (cdev->private->iretry > 0) {
+ cdev->private->iretry--;
+ ret = cio_start (sch, cdev->private->iccws,
+ cdev->private->imask);
+ /* ret is 0, -EBUSY, -EACCES or -ENODEV */
+ if ((ret != -EACCES) && (ret != -ENODEV))
+ return ret;
+ }
+ /* nop command failed on this path. Switch it off. */
+ sch->lpm &= ~cdev->private->imask;
+ sch->vpm &= ~cdev->private->imask;
+ CIO_MSG_EVENT(2, "NOP - Device %04x on Subchannel "
+ "0.%x.%04x, lpm %02X, became 'not operational'\n",
+ cdev->private->devno, sch->schid.ssid,
+ sch->schid.sch_no, cdev->private->imask);
+ return ret;
+}
+
+
+/*
* Called from interrupt context to check if a valid answer
* to Set Path Group ID was received.
*/
@@ -282,6 +345,29 @@ __ccw_device_check_pgid(struct ccw_device *cdev)
return 0;
}
+/*
+ * Called from interrupt context to check the path status after a nop has
+ * been send.
+ */
+static int __ccw_device_check_nop(struct ccw_device *cdev)
+{
+ struct subchannel *sch;
+ struct irb *irb;
+
+ sch = to_subchannel(cdev->dev.parent);
+ irb = &cdev->private->irb;
+ if (irb->scsw.fctl & (SCSW_FCTL_HALT_FUNC | SCSW_FCTL_CLEAR_FUNC))
+ return -ETIME;
+ if (irb->scsw.cc == 3) {
+ CIO_MSG_EVENT(2, "NOP - Device %04x on Subchannel 0.%x.%04x,"
+ " lpm %02X, became 'not operational'\n",
+ cdev->private->devno, sch->schid.ssid,
+ sch->schid.sch_no, cdev->private->imask);
+ return -EACCES;
+ }
+ return 0;
+}
+
static void
__ccw_device_verify_start(struct ccw_device *cdev)
{
@@ -296,9 +382,12 @@ __ccw_device_verify_start(struct ccw_device *cdev)
if ((sch->vpm & imask) != (sch->lpm & imask))
break;
cdev->private->imask = imask;
- func = (sch->vpm & imask) ?
- SPID_FUNC_RESIGN : SPID_FUNC_ESTABLISH;
- ret = __ccw_device_do_pgid(cdev, func);
+ if (cdev->private->options.pgroup) {
+ func = (sch->vpm & imask) ?
+ SPID_FUNC_RESIGN : SPID_FUNC_ESTABLISH;
+ ret = __ccw_device_do_pgid(cdev, func);
+ } else
+ ret = __ccw_device_do_nop(cdev);
if (ret == 0 || ret == -EBUSY)
return;
cdev->private->iretry = 5;
@@ -317,17 +406,20 @@ ccw_device_verify_irq(struct ccw_device *cdev, enum dev_event dev_event)
int ret;
irb = (struct irb *) __LC_IRB;
- /* Retry set pgid for cc=1. */
+
if (irb->scsw.stctl ==
(SCSW_STCTL_STATUS_PEND | SCSW_STCTL_ALERT_STATUS)) {
- if (irb->scsw.cc == 1)
+ if (__ccw_device_should_retry(&irb->scsw))
__ccw_device_verify_start(cdev);
return;
}
if (ccw_device_accumulate_and_sense(cdev, irb) != 0)
return;
sch = to_subchannel(cdev->dev.parent);
- ret = __ccw_device_check_pgid(cdev);
+ if (cdev->private->options.pgroup)
+ ret = __ccw_device_check_pgid(cdev);
+ else
+ ret = __ccw_device_check_nop(cdev);
memset(&cdev->private->irb, 0, sizeof(struct irb));
switch (ret) {
/* 0, -ETIME, -EAGAIN, -EOPNOTSUPP or -EACCES */
@@ -345,11 +437,10 @@ ccw_device_verify_irq(struct ccw_device *cdev, enum dev_event dev_event)
* One of those strange devices which claim to be able
* to do multipathing but not for Set Path Group ID.
*/
- if (cdev->private->flags.pgid_single) {
- ccw_device_verify_done(cdev, -EOPNOTSUPP);
- break;
- }
- cdev->private->flags.pgid_single = 1;
+ if (cdev->private->flags.pgid_single)
+ cdev->private->options.pgroup = 0;
+ else
+ cdev->private->flags.pgid_single = 1;
/* fall through. */
case -EAGAIN: /* Try again. */
__ccw_device_verify_start(cdev);
@@ -418,10 +509,10 @@ ccw_device_disband_irq(struct ccw_device *cdev, enum dev_event dev_event)
int ret;
irb = (struct irb *) __LC_IRB;
- /* Retry set pgid for cc=1. */
+
if (irb->scsw.stctl ==
(SCSW_STCTL_STATUS_PEND | SCSW_STCTL_ALERT_STATUS)) {
- if (irb->scsw.cc == 1)
+ if (__ccw_device_should_retry(&irb->scsw))
__ccw_device_disband_start(cdev);
return;
}
generated by cgit v1.2.3 (git 2.25.1) at 2024-12-15 15:35:25 +0000