diff options
| -rw-r--r-- | drivers/scsi/sr.c | 46 | ||||
| -rw-r--r-- | drivers/scsi/sr.h | 7 |
2 files changed, 49 insertions, 4 deletions
diff --git a/drivers/scsi/sr.c b/drivers/scsi/sr.c index 4778e27..5fc97d2 100644 --- a/drivers/scsi/sr.c +++ b/drivers/scsi/sr.c @@ -221,14 +221,33 @@ static unsigned int sr_check_events(struct cdrom_device_info *cdi, return 0; events = sr_get_events(cd->device); + cd->get_event_changed |= events & DISK_EVENT_MEDIA_CHANGE; + + /* + * If earlier GET_EVENT_STATUS_NOTIFICATION and TUR did not agree + * for several times in a row. We rely on TUR only for this likely + * broken device, to prevent generating incorrect media changed + * events for every open(). + */ + if (cd->ignore_get_event) { + events &= ~DISK_EVENT_MEDIA_CHANGE; + goto do_tur; + } + /* * GET_EVENT_STATUS_NOTIFICATION is enough unless MEDIA_CHANGE * is being cleared. Note that there are devices which hang * if asked to execute TUR repeatedly. */ - if (!(clearing & DISK_EVENT_MEDIA_CHANGE)) - goto skip_tur; + if (cd->device->changed) { + events |= DISK_EVENT_MEDIA_CHANGE; + cd->device->changed = 0; + cd->tur_changed = true; + } + if (!(clearing & DISK_EVENT_MEDIA_CHANGE)) + return events; +do_tur: /* let's see whether the media is there with TUR */ last_present = cd->media_present; ret = scsi_test_unit_ready(cd->device, SR_TIMEOUT, MAX_RETRIES, &sshdr); @@ -242,12 +261,31 @@ static unsigned int sr_check_events(struct cdrom_device_info *cdi, (scsi_sense_valid(&sshdr) && sshdr.asc != 0x3a); if (last_present != cd->media_present) - events |= DISK_EVENT_MEDIA_CHANGE; -skip_tur: + cd->device->changed = 1; + if (cd->device->changed) { events |= DISK_EVENT_MEDIA_CHANGE; cd->device->changed = 0; + cd->tur_changed = true; + } + + if (cd->ignore_get_event) + return events; + + /* check whether GET_EVENT is reporting spurious MEDIA_CHANGE */ + if (!cd->tur_changed) { + if (cd->get_event_changed) { + if (cd->tur_mismatch++ > 8) { + sdev_printk(KERN_WARNING, cd->device, + "GET_EVENT and TUR disagree continuously, suppress GET_EVENT events\n"); + cd->ignore_get_event = true; + } + } else { + cd->tur_mismatch = 0; + } } + cd->tur_changed = false; + cd->get_event_changed = false; return events; } diff --git a/drivers/scsi/sr.h b/drivers/scsi/sr.h index e036f1d..37c8f6b 100644 --- a/drivers/scsi/sr.h +++ b/drivers/scsi/sr.h @@ -41,6 +41,13 @@ typedef struct scsi_cd { unsigned readcd_known:1; /* drive supports READ_CD (0xbe) */ unsigned readcd_cdda:1; /* reading audio data using READ_CD */ unsigned media_present:1; /* media is present */ + + /* GET_EVENT spurious event handling, blk layer guarantees exclusion */ + int tur_mismatch; /* nr of get_event TUR mismatches */ + bool tur_changed:1; /* changed according to TUR */ + bool get_event_changed:1; /* changed according to GET_EVENT */ + bool ignore_get_event:1; /* GET_EVENT is unreliable, use TUR */ + struct cdrom_device_info cdi; /* We hold gendisk and scsi_device references on probe and use * the refs on this kref to decide when to release them */ |
