[SCSI] sd: implement sd_check_events()
Replace sd_media_change() with sd_check_events().
* Move media removed logic into set_media_not_present() and
media_not_present() and set sdev->changed iff an existing media is
removed or the device indicates UNIT_ATTENTION.
* Make sd_check_events() sets sdev->changed if previously missing
media becomes present.
* Event is reported only if sdev->changed is set.
This makes media presence event reported if scsi_disk->media_present
actually changed or the device indicated UNIT_ATTENTION. For backward
compatibility, SDEV_EVT_MEDIA_CHANGE is generated each time
sd_check_events() detects media change event.
[jejb: fix boot failure]
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Jens Axboe <jaxboe@fusionio.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
diff --git a/drivers/scsi/sd.c b/drivers/scsi/sd.c
index b65e65a..7d25746 100644
--- a/drivers/scsi/sd.c
+++ b/drivers/scsi/sd.c
@@ -990,30 +990,51 @@
static void set_media_not_present(struct scsi_disk *sdkp)
{
- sdkp->media_present = 0;
- sdkp->capacity = 0;
- sdkp->device->changed = 1;
+ if (sdkp->media_present)
+ sdkp->device->changed = 1;
+
+ if (sdkp->device->removable) {
+ sdkp->media_present = 0;
+ sdkp->capacity = 0;
+ }
+}
+
+static int media_not_present(struct scsi_disk *sdkp,
+ struct scsi_sense_hdr *sshdr)
+{
+ if (!scsi_sense_valid(sshdr))
+ return 0;
+
+ /* not invoked for commands that could return deferred errors */
+ switch (sshdr->sense_key) {
+ case UNIT_ATTENTION:
+ case NOT_READY:
+ /* medium not present */
+ if (sshdr->asc == 0x3A) {
+ set_media_not_present(sdkp);
+ return 1;
+ }
+ }
+ return 0;
}
/**
- * sd_media_changed - check if our medium changed
- * @disk: kernel device descriptor
+ * sd_check_events - check media events
+ * @disk: kernel device descriptor
+ * @clearing: disk events currently being cleared
*
- * Returns 0 if not applicable or no change; 1 if change
+ * Returns mask of DISK_EVENT_*.
*
* Note: this function is invoked from the block subsystem.
**/
-static int sd_media_changed(struct gendisk *disk)
+static unsigned int sd_check_events(struct gendisk *disk, unsigned int clearing)
{
struct scsi_disk *sdkp = scsi_disk(disk);
struct scsi_device *sdp = sdkp->device;
struct scsi_sense_hdr *sshdr = NULL;
int retval;
- SCSI_LOG_HLQUEUE(3, sd_printk(KERN_INFO, sdkp, "sd_media_changed\n"));
-
- if (!sdp->removable)
- return 0;
+ SCSI_LOG_HLQUEUE(3, sd_printk(KERN_INFO, sdkp, "sd_check_events\n"));
/*
* If the device is offline, don't send any commands - just pretend as
@@ -1043,40 +1064,37 @@
sshdr);
}
- if (retval) {
+ /* failed to execute TUR, assume media not present */
+ if (host_byte(retval)) {
set_media_not_present(sdkp);
goto out;
}
+ if (media_not_present(sdkp, sshdr))
+ goto out;
+
/*
* For removable scsi disk we have to recognise the presence
- * of a disk in the drive. This is kept in the struct scsi_disk
- * struct and tested at open ! Daniel Roche (dan@lectra.fr)
+ * of a disk in the drive.
*/
+ if (!sdkp->media_present)
+ sdp->changed = 1;
sdkp->media_present = 1;
-
out:
/*
- * Report a media change under the following conditions:
+ * sdp->changed is set under the following conditions:
*
- * Medium is present now and wasn't present before.
- * Medium wasn't present before and is present now.
- * Medium was present at all times, but it changed while
- * we weren't looking (sdp->changed is set).
+ * Medium present state has changed in either direction.
+ * Device has indicated UNIT_ATTENTION.
*
- * If there was no medium before and there is no medium now then
- * don't report a change, even if a medium was inserted and removed
- * while we weren't looking.
+ * Report SDEV_EVT_MEDIA_CHANGE too for backward compatibility.
*/
- retval = (sdkp->media_present != sdkp->previous_state ||
- (sdkp->media_present && sdp->changed));
- if (retval)
+ if (sdp->changed)
sdev_evt_send_simple(sdp, SDEV_EVT_MEDIA_CHANGE, GFP_KERNEL);
- sdkp->previous_state = sdkp->media_present;
-
- /* sdp->changed indicates medium was changed or is not present */
- sdp->changed = !sdkp->media_present;
kfree(sshdr);
+
+ retval = sdp->changed ? DISK_EVENT_MEDIA_CHANGE : 0;
+ sdp->changed = 0;
return retval;
}
@@ -1169,7 +1187,7 @@
#ifdef CONFIG_COMPAT
.compat_ioctl = sd_compat_ioctl,
#endif
- .media_changed = sd_media_changed,
+ .check_events = sd_check_events,
.revalidate_disk = sd_revalidate_disk,
.unlock_native_capacity = sd_unlock_native_capacity,
};
@@ -1312,23 +1330,6 @@
return good_bytes;
}
-static int media_not_present(struct scsi_disk *sdkp,
- struct scsi_sense_hdr *sshdr)
-{
-
- if (!scsi_sense_valid(sshdr))
- return 0;
- /* not invoked for commands that could return deferred errors */
- if (sshdr->sense_key != NOT_READY &&
- sshdr->sense_key != UNIT_ATTENTION)
- return 0;
- if (sshdr->asc != 0x3A) /* medium not present */
- return 0;
-
- set_media_not_present(sdkp);
- return 1;
-}
-
/*
* spinup disk - called only in sd_revalidate_disk()
*/
@@ -1503,7 +1504,7 @@
*/
if (sdp->removable &&
sense_valid && sshdr->sense_key == NOT_READY)
- sdp->changed = 1;
+ set_media_not_present(sdkp);
/*
* We used to set media_present to 0 here to indicate no media
@@ -2389,8 +2390,10 @@
gd->driverfs_dev = &sdp->sdev_gendev;
gd->flags = GENHD_FL_EXT_DEVT;
- if (sdp->removable)
+ if (sdp->removable) {
gd->flags |= GENHD_FL_REMOVABLE;
+ gd->events |= DISK_EVENT_MEDIA_CHANGE;
+ }
add_disk(gd);
sd_dif_config_host(sdkp);
@@ -2472,7 +2475,6 @@
sdkp->disk = gd;
sdkp->index = index;
atomic_set(&sdkp->openers, 0);
- sdkp->previous_state = 1;
if (!sdp->request_queue->rq_timeout) {
if (sdp->type != TYPE_MOD)