diff options
Diffstat (limited to 'drivers/s390/cio/cio.c')
| -rw-r--r-- | drivers/s390/cio/cio.c | 69 |
1 files changed, 69 insertions, 0 deletions
diff --git a/drivers/s390/cio/cio.c b/drivers/s390/cio/cio.c index 1b350665c823..89216174fcbb 100644 --- a/drivers/s390/cio/cio.c +++ b/drivers/s390/cio/cio.c @@ -170,12 +170,14 @@ cio_start_key (struct subchannel *sch, /* subchannel structure */ 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 @@ -208,6 +210,7 @@ cio_resume (struct subchannel *sch) return -ENODEV; } } +EXPORT_SYMBOL_GPL(cio_resume); /* * halt I/O operation @@ -241,6 +244,7 @@ cio_halt(struct subchannel *sch) return -ENODEV; } } +EXPORT_SYMBOL_GPL(cio_halt); /* * Clear I/O operation @@ -271,6 +275,7 @@ cio_clear(struct subchannel *sch) return -ENODEV; } } +EXPORT_SYMBOL_GPL(cio_clear); /* * Function: cio_cancel @@ -308,7 +313,68 @@ cio_cancel (struct subchannel *sch) 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) { @@ -382,6 +448,7 @@ int cio_commit_config(struct subchannel *sch) } return ret; } +EXPORT_SYMBOL_GPL(cio_commit_config); /** * cio_update_schib - Perform stsch and update schib if subchannel is valid. @@ -987,6 +1054,7 @@ int cio_tm_start_key(struct subchannel *sch, struct tcw *tcw, u8 lpm, u8 key) return cio_start_handle_notoper(sch, lpm); } } +EXPORT_SYMBOL_GPL(cio_tm_start_key); /** * cio_tm_intrg - perform interrogate function @@ -1012,3 +1080,4 @@ int cio_tm_intrg(struct subchannel *sch) return -ENODEV; } } +EXPORT_SYMBOL_GPL(cio_tm_intrg); |