From 93aae17af1172c40c6f74b7294e93a90c3cfaa5d Mon Sep 17 00:00:00 2001 From: Tejun Heo Date: Thu, 16 Dec 2010 17:52:17 +0100 Subject: sr: implement sr_check_events() Replace sr_media_change() with sr_check_events(). It normally only uses GET_EVENT_STATUS_NOTIFICATION to check both media change and eject request. If @clearing includes DISK_EVENT_MEDIA_CHANGE, it issues TUR and compares whether media presence has changed. The SCSI specific media change uevent is kept for compatibility. sr_media_change() was doing both media change check and revalidation. The revalidation part is split into sr_block_revalidate_disk(). Signed-off-by: Tejun Heo Cc: Kay Sievers Signed-off-by: Jens Axboe --- drivers/scsi/sr.c | 149 +++++++++++++++++++++++++++++++++++------------------- drivers/scsi/sr.h | 2 +- 2 files changed, 98 insertions(+), 53 deletions(-) (limited to 'drivers/scsi') diff --git a/drivers/scsi/sr.c b/drivers/scsi/sr.c index 310b3fa..be6baf8 100644 --- a/drivers/scsi/sr.c +++ b/drivers/scsi/sr.c @@ -104,14 +104,15 @@ static void sr_release(struct cdrom_device_info *); static void get_sectorsize(struct scsi_cd *); static void get_capabilities(struct scsi_cd *); -static int sr_media_change(struct cdrom_device_info *, int); +static unsigned int sr_check_events(struct cdrom_device_info *cdi, + unsigned int clearing, int slot); static int sr_packet(struct cdrom_device_info *, struct packet_command *); static struct cdrom_device_ops sr_dops = { .open = sr_open, .release = sr_release, .drive_status = sr_drive_status, - .media_changed = sr_media_change, + .check_events = sr_check_events, .tray_move = sr_tray_move, .lock_door = sr_lock_door, .select_speed = sr_select_speed, @@ -165,69 +166,96 @@ static void scsi_cd_put(struct scsi_cd *cd) mutex_unlock(&sr_ref_mutex); } +static unsigned int sr_get_events(struct scsi_device *sdev) +{ + u8 buf[8]; + u8 cmd[] = { GET_EVENT_STATUS_NOTIFICATION, + 1, /* polled */ + 0, 0, /* reserved */ + 1 << 4, /* notification class: media */ + 0, 0, /* reserved */ + 0, sizeof(buf), /* allocation length */ + 0, /* control */ + }; + struct event_header *eh = (void *)buf; + struct media_event_desc *med = (void *)(buf + 4); + struct scsi_sense_hdr sshdr; + int result; + + result = scsi_execute_req(sdev, cmd, DMA_FROM_DEVICE, buf, sizeof(buf), + &sshdr, SR_TIMEOUT, MAX_RETRIES, NULL); + if (scsi_sense_valid(&sshdr) && sshdr.sense_key == UNIT_ATTENTION) + return DISK_EVENT_MEDIA_CHANGE; + + if (result || be16_to_cpu(eh->data_len) < sizeof(*med)) + return 0; + + if (eh->nea || eh->notification_class != 0x4) + return 0; + + if (med->media_event_code == 1) + return DISK_EVENT_EJECT_REQUEST; + else if (med->media_event_code == 2) + return DISK_EVENT_MEDIA_CHANGE; + return 0; +} + /* - * This function checks to see if the media has been changed in the - * CDROM drive. It is possible that we have already sensed a change, - * or the drive may have sensed one and not yet reported it. We must - * be ready for either case. This function always reports the current - * value of the changed bit. If flag is 0, then the changed bit is reset. - * This function could be done as an ioctl, but we would need to have - * an inode for that to work, and we do not always have one. + * This function checks to see if the media has been changed or eject + * button has been pressed. It is possible that we have already + * sensed a change, or the drive may have sensed one and not yet + * reported it. The past events are accumulated in sdev->changed and + * returned together with the current state. */ - -static int sr_media_change(struct cdrom_device_info *cdi, int slot) +static unsigned int sr_check_events(struct cdrom_device_info *cdi, + unsigned int clearing, int slot) { struct scsi_cd *cd = cdi->handle; - int retval; - struct scsi_sense_hdr *sshdr; + bool last_present; + struct scsi_sense_hdr sshdr; + unsigned int events; + int ret; - if (CDSL_CURRENT != slot) { - /* no changer support */ - return -EINVAL; - } + /* no changer support */ + if (CDSL_CURRENT != slot) + return 0; + + events = sr_get_events(cd->device); + /* + * 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; + + /* 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); - sshdr = kzalloc(sizeof(*sshdr), GFP_KERNEL); - retval = scsi_test_unit_ready(cd->device, SR_TIMEOUT, MAX_RETRIES, - sshdr); /* * Media is considered to be present if TUR succeeds or fails with * sense data indicating something other than media-not-present * (ASC 0x3a). */ - if (!scsi_status_is_good(retval) && - (!scsi_sense_valid(sshdr) || sshdr->asc == 0x3a)) { - /* - * Probably no media in the device. Mark as changed, and - * we will figure it out later once the drive is available - * again. - */ - cd->device->changed = 1; - /* This will force a flush, if called from check_disk_change */ - retval = 1; - goto out; - }; + cd->media_present = scsi_status_is_good(ret) || + (scsi_sense_valid(&sshdr) && sshdr.asc != 0x3a); - retval = cd->device->changed; - cd->device->changed = 0; - /* If the disk changed, the capacity will now be different, - * so we force a re-read of this information */ - if (retval) { - /* check multisession offset etc */ - sr_cd_check(cdi); - get_sectorsize(cd); + if (last_present != cd->media_present) + events |= DISK_EVENT_MEDIA_CHANGE; +skip_tur: + if (cd->device->changed) { + events |= DISK_EVENT_MEDIA_CHANGE; + cd->device->changed = 0; } -out: - /* Notify userspace, that media has changed. */ - if (retval != cd->previous_state) + /* for backward compatibility */ + if (events & DISK_EVENT_MEDIA_CHANGE) sdev_evt_send_simple(cd->device, SDEV_EVT_MEDIA_CHANGE, GFP_KERNEL); - cd->previous_state = retval; - kfree(sshdr); - - return retval; + return events; } - + /* * sr_done is the interrupt routine for the device driver. * @@ -512,10 +540,25 @@ out: return ret; } -static int sr_block_media_changed(struct gendisk *disk) +static unsigned int sr_block_check_events(struct gendisk *disk, + unsigned int clearing) { struct scsi_cd *cd = scsi_cd(disk); - return cdrom_media_changed(&cd->cdi); + return cdrom_check_events(&cd->cdi, clearing); +} + +static int sr_block_revalidate_disk(struct gendisk *disk) +{ + struct scsi_cd *cd = scsi_cd(disk); + struct scsi_sense_hdr sshdr; + + /* if the unit is not ready, nothing more to do */ + if (scsi_test_unit_ready(cd->device, SR_TIMEOUT, MAX_RETRIES, &sshdr)) + return 0; + + sr_cd_check(&cd->cdi); + get_sectorsize(cd); + return 0; } static const struct block_device_operations sr_bdops = @@ -524,7 +567,8 @@ static const struct block_device_operations sr_bdops = .open = sr_block_open, .release = sr_block_release, .ioctl = sr_block_ioctl, - .media_changed = sr_block_media_changed, + .check_events = sr_block_check_events, + .revalidate_disk = sr_block_revalidate_disk, /* * No compat_ioctl for now because sr_block_ioctl never * seems to pass arbitary ioctls down to host drivers. @@ -597,6 +641,7 @@ static int sr_probe(struct device *dev) sprintf(disk->disk_name, "sr%d", minor); disk->fops = &sr_bdops; disk->flags = GENHD_FL_CD; + disk->events = DISK_EVENT_MEDIA_CHANGE | DISK_EVENT_EJECT_REQUEST; blk_queue_rq_timeout(sdev->request_queue, SR_TIMEOUT); @@ -606,7 +651,7 @@ static int sr_probe(struct device *dev) cd->disk = disk; cd->capacity = 0x1fffff; cd->device->changed = 1; /* force recheck CD type */ - cd->previous_state = 1; + cd->media_present = 1; cd->use = 1; cd->readcd_known = 0; cd->readcd_cdda = 0; diff --git a/drivers/scsi/sr.h b/drivers/scsi/sr.h index 81fbc0b..e036f1d 100644 --- a/drivers/scsi/sr.h +++ b/drivers/scsi/sr.h @@ -40,7 +40,7 @@ typedef struct scsi_cd { unsigned xa_flag:1; /* CD has XA sectors ? */ unsigned readcd_known:1; /* drive supports READ_CD (0xbe) */ unsigned readcd_cdda:1; /* reading audio data using READ_CD */ - unsigned previous_state:1; /* media has changed */ + unsigned media_present:1; /* media is present */ 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 */ -- cgit v1.1