diff options
Diffstat (limited to 'drivers/s390/cio/device_pgid.c')
-rw-r--r-- | drivers/s390/cio/device_pgid.c | 448 |
1 files changed, 448 insertions, 0 deletions
diff --git a/drivers/s390/cio/device_pgid.c b/drivers/s390/cio/device_pgid.c new file mode 100644 index 000000000000..0adac8a67331 --- /dev/null +++ b/drivers/s390/cio/device_pgid.c @@ -0,0 +1,448 @@ +/* + * drivers/s390/cio/device_pgid.c + * + * Copyright (C) 2002 IBM Deutschland Entwicklung GmbH, + * IBM Corporation + * Author(s): Cornelia Huck(cohuck@de.ibm.com) + * Martin Schwidefsky (schwidefsky@de.ibm.com) + * + * Path Group ID functions. + */ + +#include <linux/config.h> +#include <linux/module.h> +#include <linux/init.h> + +#include <asm/ccwdev.h> +#include <asm/cio.h> +#include <asm/delay.h> +#include <asm/lowcore.h> + +#include "cio.h" +#include "cio_debug.h" +#include "css.h" +#include "device.h" + +/* + * Start Sense Path Group ID helper function. Used in ccw_device_recog + * and ccw_device_sense_pgid. + */ +static int +__ccw_device_sense_pgid_start(struct ccw_device *cdev) +{ + struct subchannel *sch; + struct ccw1 *ccw; + int ret; + + sch = to_subchannel(cdev->dev.parent); + /* 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; + + /* Reset device status. */ + memset(&cdev->private->irb, 0, sizeof(struct irb)); + /* Try on every path. */ + ret = -ENODEV; + while (cdev->private->imask != 0) { + /* Try every path multiple times. */ + 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) + return ret; + CIO_MSG_EVENT(2, "SNID - Device %04x on Subchannel " + "%04x, lpm %02X, became 'not " + "operational'\n", + cdev->private->devno, sch->irq, + cdev->private->imask); + + } + cdev->private->imask >>= 1; + cdev->private->iretry = 5; + } + return ret; +} + +void +ccw_device_sense_pgid_start(struct ccw_device *cdev) +{ + int ret; + + cdev->private->state = DEV_STATE_SENSE_PGID; + cdev->private->imask = 0x80; + cdev->private->iretry = 5; + memset (&cdev->private->pgid, 0, sizeof (struct pgid)); + ret = __ccw_device_sense_pgid_start(cdev); + if (ret && ret != -EBUSY) + ccw_device_sense_pgid_done(cdev, ret); +} + +/* + * Called from interrupt context to check if a valid answer + * to Sense Path Group ID was received. + */ +static int +__ccw_device_check_sense_pgid(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->esw.esw0.erw.cons && + (irb->ecw[0]&(SNS0_CMD_REJECT|SNS0_INTERVENTION_REQ))) { + /* + * If the device doesn't support the Sense Path Group ID + * command further retries wouldn't help ... + */ + return -EOPNOTSUPP; + } + if (irb->esw.esw0.erw.cons) { + CIO_MSG_EVENT(2, "SNID - device %04x, unit check, " + "lpum %02X, cnt %02d, sns : " + "%02X%02X%02X%02X %02X%02X%02X%02X ...\n", + cdev->private->devno, + irb->esw.esw0.sublog.lpum, + irb->esw.esw0.erw.scnt, + irb->ecw[0], irb->ecw[1], + irb->ecw[2], irb->ecw[3], + irb->ecw[4], irb->ecw[5], + irb->ecw[6], irb->ecw[7]); + return -EAGAIN; + } + if (irb->scsw.cc == 3) { + CIO_MSG_EVENT(2, "SNID - Device %04x on Subchannel " + "%04x, lpm %02X, became 'not operational'\n", + cdev->private->devno, sch->irq, sch->orb.lpm); + return -EACCES; + } + if (cdev->private->pgid.inf.ps.state2 == SNID_STATE2_RESVD_ELSE) { + CIO_MSG_EVENT(2, "SNID - Device %04x on Subchannel %04x " + "is reserved by someone else\n", + cdev->private->devno, sch->irq); + return -EUSERS; + } + return 0; +} + +/* + * Got interrupt for Sense Path Group ID. + */ +void +ccw_device_sense_pgid_irq(struct ccw_device *cdev, enum dev_event dev_event) +{ + struct subchannel *sch; + struct irb *irb; + 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) { + ret = __ccw_device_sense_pgid_start(cdev); + if (ret && ret != -EBUSY) + ccw_device_sense_pgid_done(cdev, ret); + } + return; + } + if (ccw_device_accumulate_and_sense(cdev, irb) != 0) + return; + sch = to_subchannel(cdev->dev.parent); + ret = __ccw_device_check_sense_pgid(cdev); + 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, &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; + case -ETIME: /* Sense path group id stopped by timeout. */ + ccw_device_sense_pgid_done(cdev, -ETIME); + break; + case -EACCES: /* channel is not operational. */ + sch->lpm &= ~cdev->private->imask; + 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); + break; + case -EUSERS: /* device is reserved for someone else. */ + ccw_device_sense_pgid_done(cdev, -EUSERS); + break; + } +} + +/* + * Path Group ID helper function. + */ +static int +__ccw_device_do_pgid(struct ccw_device *cdev, __u8 func) +{ + struct subchannel *sch; + struct ccw1 *ccw; + int ret; + + sch = to_subchannel(cdev->dev.parent); + + /* Setup sense path group id channel program. */ + cdev->private->pgid.inf.fc = func; + ccw = cdev->private->iccws; + if (!cdev->private->flags.pgid_single) { + cdev->private->pgid.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; + + ccw->cmd_code = CCW_CMD_SET_PGID; + ccw->cda = (__u32) __pa (&cdev->private->pgid); + ccw->count = sizeof (struct pgid); + 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; + } + /* PGID command failed on this path. Switch it off. */ + sch->lpm &= ~cdev->private->imask; + sch->vpm &= ~cdev->private->imask; + CIO_MSG_EVENT(2, "SPID - Device %04x on Subchannel " + "%04x, lpm %02X, became 'not operational'\n", + cdev->private->devno, sch->irq, cdev->private->imask); + return ret; +} + +/* + * Called from interrupt context to check if a valid answer + * to Set Path Group ID was received. + */ +static int +__ccw_device_check_pgid(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->esw.esw0.erw.cons) { + if (irb->ecw[0] & SNS0_CMD_REJECT) + return -EOPNOTSUPP; + /* Hmm, whatever happened, try again. */ + CIO_MSG_EVENT(2, "SPID - device %04x, unit check, cnt %02d, " + "sns : %02X%02X%02X%02X %02X%02X%02X%02X ...\n", + cdev->private->devno, irb->esw.esw0.erw.scnt, + irb->ecw[0], irb->ecw[1], + irb->ecw[2], irb->ecw[3], + irb->ecw[4], irb->ecw[5], + irb->ecw[6], irb->ecw[7]); + return -EAGAIN; + } + if (irb->scsw.cc == 3) { + CIO_MSG_EVENT(2, "SPID - Device %04x on Subchannel " + "%04x, lpm %02X, became 'not operational'\n", + cdev->private->devno, sch->irq, + cdev->private->imask); + return -EACCES; + } + return 0; +} + +static void +__ccw_device_verify_start(struct ccw_device *cdev) +{ + struct subchannel *sch; + __u8 imask, func; + int ret; + + sch = to_subchannel(cdev->dev.parent); + while (sch->vpm != sch->lpm) { + /* Find first unequal bit in vpm vs. lpm */ + for (imask = 0x80; imask != 0; imask >>= 1) + 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 (ret == 0 || ret == -EBUSY) + return; + cdev->private->iretry = 5; + } + ccw_device_verify_done(cdev, (sch->lpm != 0) ? 0 : -ENODEV); +} + +/* + * Got interrupt for Set Path Group ID. + */ +void +ccw_device_verify_irq(struct ccw_device *cdev, enum dev_event dev_event) +{ + struct subchannel *sch; + struct irb *irb; + 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) + __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); + memset(&cdev->private->irb, 0, sizeof(struct irb)); + switch (ret) { + /* 0, -ETIME, -EAGAIN, -EOPNOTSUPP or -EACCES */ + case 0: + /* Establish or Resign Path Group done. Update vpm. */ + if ((sch->lpm & cdev->private->imask) != 0) + sch->vpm |= cdev->private->imask; + else + sch->vpm &= ~cdev->private->imask; + cdev->private->iretry = 5; + __ccw_device_verify_start(cdev); + break; + case -EOPNOTSUPP: + /* + * 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; + /* fall through. */ + case -EAGAIN: /* Try again. */ + __ccw_device_verify_start(cdev); + break; + case -ETIME: /* Set path group id stopped by timeout. */ + ccw_device_verify_done(cdev, -ETIME); + break; + case -EACCES: /* channel is not operational. */ + sch->lpm &= ~cdev->private->imask; + sch->vpm &= ~cdev->private->imask; + cdev->private->iretry = 5; + __ccw_device_verify_start(cdev); + break; + } +} + +void +ccw_device_verify_start(struct ccw_device *cdev) +{ + cdev->private->flags.pgid_single = 0; + cdev->private->iretry = 5; + __ccw_device_verify_start(cdev); +} + +static void +__ccw_device_disband_start(struct ccw_device *cdev) +{ + struct subchannel *sch; + int ret; + + sch = to_subchannel(cdev->dev.parent); + while (cdev->private->imask != 0) { + if (sch->lpm & cdev->private->imask) { + ret = __ccw_device_do_pgid(cdev, SPID_FUNC_DISBAND); + if (ret == 0) + return; + } + cdev->private->iretry = 5; + cdev->private->imask >>= 1; + } + ccw_device_verify_done(cdev, (sch->lpm != 0) ? 0 : -ENODEV); +} + +/* + * Got interrupt for Unset Path Group ID. + */ +void +ccw_device_disband_irq(struct ccw_device *cdev, enum dev_event dev_event) +{ + struct subchannel *sch; + struct irb *irb; + 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) + __ccw_device_disband_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); + memset(&cdev->private->irb, 0, sizeof(struct irb)); + switch (ret) { + /* 0, -ETIME, -EAGAIN, -EOPNOTSUPP or -EACCES */ + case 0: /* disband successful. */ + sch->vpm = 0; + ccw_device_disband_done(cdev, ret); + break; + case -EOPNOTSUPP: + /* + * One of those strange devices which claim to be able + * to do multipathing but not for Unset Path Group ID. + */ + cdev->private->flags.pgid_single = 1; + /* fall through. */ + case -EAGAIN: /* Try again. */ + __ccw_device_disband_start(cdev); + break; + case -ETIME: /* Set path group id stopped by timeout. */ + ccw_device_disband_done(cdev, -ETIME); + break; + case -EACCES: /* channel is not operational. */ + cdev->private->imask >>= 1; + cdev->private->iretry = 5; + __ccw_device_disband_start(cdev); + break; + } +} + +void +ccw_device_disband_start(struct ccw_device *cdev) +{ + cdev->private->flags.pgid_single = 0; + cdev->private->iretry = 5; + cdev->private->imask = 0x80; + __ccw_device_disband_start(cdev); +} |