Revert "sd: implement sd_check_events()"
Jens Axboe [Wed, 22 Dec 2010 08:48:49 +0000 (09:48 +0100)]
This reverts commit c8d2e937355d02db3055c2fc203e5f017297ee1f.

We run into merging problems with the SCSI tree, revert this one
so it can be handled by a postmerge tree there.

Signed-off-by: Jens Axboe <jaxboe@fusionio.com>

drivers/scsi/sd.c
drivers/scsi/sd.h

index b179b0e..8d488a9 100644 (file)
@@ -991,50 +991,30 @@ out:
 
 static void set_media_not_present(struct scsi_disk *sdkp)
 {
-       if (sdkp->media_present)
-               sdkp->device->changed = 1;
        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:
-               sdkp->device->changed = 1;
-               /* fall through */
-       case NOT_READY:
-               /* medium not present */
-               if (sshdr->asc == 0x3A) {
-                       set_media_not_present(sdkp);
-                       return 1;
-               }
-       }
-       return 0;
+       sdkp->device->changed = 1;
 }
 
 /**
- *     sd_check_events - check media events
- *     @disk: kernel device descriptor
- *     @clearing: disk events currently being cleared
+ *     sd_media_changed - check if our medium changed
+ *     @disk: kernel device descriptor 
  *
- *     Returns mask of DISK_EVENT_*.
+ *     Returns 0 if not applicable or no change; 1 if change
  *
  *     Note: this function is invoked from the block subsystem.
  **/
-static unsigned int sd_check_events(struct gendisk *disk, unsigned int clearing)
+static int sd_media_changed(struct gendisk *disk)
 {
        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_check_events\n"));
+       SCSI_LOG_HLQUEUE(3, sd_printk(KERN_INFO, sdkp, "sd_media_changed\n"));
+
+       if (!sdp->removable)
+               return 0;
 
        /*
         * If the device is offline, don't send any commands - just pretend as
@@ -1044,6 +1024,7 @@ static unsigned int sd_check_events(struct gendisk *disk, unsigned int clearing)
         */
        if (!scsi_device_online(sdp)) {
                set_media_not_present(sdkp);
+               retval = 1;
                goto out;
        }
 
@@ -1064,30 +1045,26 @@ static unsigned int sd_check_events(struct gendisk *disk, unsigned int clearing)
                                              sshdr);
        }
 
-       /* failed to execute TUR, assume media not present */
-       if (host_byte(retval)) {
+       if (retval) {
                set_media_not_present(sdkp);
+               retval = 1;
                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.
+        * of a disk in the drive. This is kept in the struct scsi_disk
+        * struct and tested at open !  Daniel Roche (dan@lectra.fr)
         */
-       if (!sdkp->media_present)
-               sdp->changed = 1;
        sdkp->media_present = 1;
+
+       retval = sdp->changed;
+       sdp->changed = 0;
 out:
-       /* for backward compatibility */
-       if (sdp->changed)
+       if (retval != sdkp->previous_state)
                sdev_evt_send_simple(sdp, SDEV_EVT_MEDIA_CHANGE, GFP_KERNEL);
+       sdkp->previous_state = retval;
        kfree(sshdr);
-
-       retval = sdp->changed ? DISK_EVENT_MEDIA_CHANGE : 0;
-       sdp->changed = 0;
        return retval;
 }
 
@@ -1180,7 +1157,7 @@ static const struct block_device_operations sd_fops = {
 #ifdef CONFIG_COMPAT
        .compat_ioctl           = sd_compat_ioctl,
 #endif
-       .check_events           = sd_check_events,
+       .media_changed          = sd_media_changed,
        .revalidate_disk        = sd_revalidate_disk,
        .unlock_native_capacity = sd_unlock_native_capacity,
 };
@@ -1316,6 +1293,23 @@ static int sd_done(struct scsi_cmnd *SCpnt)
        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()
  */
@@ -1490,7 +1484,7 @@ static void read_capacity_error(struct scsi_disk *sdkp, struct scsi_device *sdp,
         */
        if (sdp->removable &&
            sense_valid && sshdr->sense_key == NOT_READY)
-               set_media_not_present(sdkp);
+               sdp->changed = 1;
 
        /*
         * We used to set media_present to 0 here to indicate no media
@@ -2345,10 +2339,8 @@ static void sd_probe_async(void *data, async_cookie_t cookie)
 
        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);
@@ -2430,6 +2422,7 @@ static int sd_probe(struct device *dev)
        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)
index c9d8f6c..55488fa 100644 (file)
@@ -55,6 +55,7 @@ struct scsi_disk {
        u8              media_present;
        u8              write_prot;
        u8              protection_type;/* Data Integrity Field */
+       unsigned        previous_state : 1;
        unsigned        ATO : 1;        /* state of disk ATO bit */
        unsigned        WCE : 1;        /* state of disk WCE bit */
        unsigned        RCD : 1;        /* state of disk RCD bit, unused */