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author | Sebastian Ott <sebott@linux.ibm.com> | 2018-06-26 16:09:32 +0300 |
---|---|---|
committer | Martin Schwidefsky <schwidefsky@de.ibm.com> | 2018-07-17 08:27:55 +0300 |
commit | d4f5d79e97ca6e903700d3d9455afb5694cc4833 (patch) | |
tree | 13104c4b30fa7e9360f366c4e526640627705652 /drivers/s390/cio/cio.c | |
parent | 05b217f4c5573f34f6799698f7d4162c702132bc (diff) | |
download | linux-d4f5d79e97ca6e903700d3d9455afb5694cc4833.tar.xz |
s390/css: reduce stsch calls
Both css_evaluate_new_subchannel and cio_validate_subchannel used
stsch and css_sch_is_valid to check for a valid device.
Reduce stsch calls during subchannel evaluation by re-using schib
data. Also the type/devno valid information is only checked once.
Signed-off-by: Sebastian Ott <sebott@linux.ibm.com>
Reviewed-by: Peter Oberparleiter <oberpar@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Diffstat (limited to 'drivers/s390/cio/cio.c')
-rw-r--r-- | drivers/s390/cio/cio.c | 65 |
1 files changed, 6 insertions, 59 deletions
diff --git a/drivers/s390/cio/cio.c b/drivers/s390/cio/cio.c index 4b8f29f83421..de744ca158fd 100644 --- a/drivers/s390/cio/cio.c +++ b/drivers/s390/cio/cio.c @@ -526,64 +526,6 @@ int cio_disable_subchannel(struct subchannel *sch) } EXPORT_SYMBOL_GPL(cio_disable_subchannel); -/** - * cio_validate_subchannel - basic validation of subchannel - * @schid: subchannel id - * @schib: subchannel information block to be filled out - * - * Check if subchannel is valid and should be used. - * Return codes: - * 0 on success - * -ENXIO for non-defined subchannels - * -ENODEV for invalid subchannels or blacklisted devices - * -EIO for subchannels in an invalid subchannel set - */ -int cio_validate_subchannel(struct subchannel_id schid, struct schib *schib) -{ - char dbf_txt[15]; - int ccode; - int err; - - sprintf(dbf_txt, "valsch%x", schid.sch_no); - CIO_TRACE_EVENT(4, dbf_txt); - - /* - * The first subchannel that is not-operational (ccode==3) - * indicates that there aren't any more devices available. - * If stsch gets an exception, it means the current subchannel set - * is not valid. - */ - ccode = stsch(schid, schib); - if (ccode) { - err = (ccode == 3) ? -ENXIO : ccode; - goto out; - } - - switch (schib->pmcw.st) { - case SUBCHANNEL_TYPE_IO: - case SUBCHANNEL_TYPE_MSG: - if (!css_sch_is_valid(schib)) - err = -ENODEV; - else if (is_blacklisted(schid.ssid, schib->pmcw.dev)) { - CIO_MSG_EVENT(6, "Blacklisted device detected " - "at devno %04X, subchannel set %x\n", - schib->pmcw.dev, schid.ssid); - err = -ENODEV; - } else - err = 0; - break; - default: - err = 0; - } - if (err) - goto out; - - CIO_MSG_EVENT(4, "Subchannel 0.%x.%04x reports subchannel type %04X\n", - schid.ssid, schid.sch_no, schib->pmcw.st); -out: - return err; -} - /* * do_cio_interrupt() handles all normal I/O device IRQ's */ @@ -707,6 +649,7 @@ 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(); @@ -716,7 +659,11 @@ struct subchannel *cio_probe_console(void) } init_subchannel_id(&schid); schid.sch_no = sch_no; - sch = css_alloc_subchannel(schid); + ret = stsch(schid, &schib); + if (ret) + return ERR_PTR(-ENODEV); + + sch = css_alloc_subchannel(schid, &schib); if (IS_ERR(sch)) return sch; |