block_device_operations->release() should return void

The value passed is 0 in all but "it can never happen" cases (and those
only in a couple of drivers) *and* it would've been lost on the way
out anyway, even if something tried to pass something meaningful.
Just don't bother.

Signed-off-by: Al Viro <[e-mail]>

arch/um/drivers/ubd_kern.c

···
 static DEFINE_MUTEX(ubd_mutex); /* replaces BKL, might not be needed */
 
 static int ubd_open(struct block_device *bdev, fmode_t mode);
-static int ubd_release(struct gendisk *disk, fmode_t mode);
+static void ubd_release(struct gendisk *disk, fmode_t mode);
 static int ubd_ioctl(struct block_device *bdev, fmode_t mode,
 		     unsigned int cmd, unsigned long arg);
 static int ubd_getgeo(struct block_device *bdev, struct hd_geometry *geo);
···
 	return err;
 }
 
-static int ubd_release(struct gendisk *disk, fmode_t mode)
+static void ubd_release(struct gendisk *disk, fmode_t mode)
 {
 	struct ubd *ubd_dev = disk->private_data;
 
···
 	if(--ubd_dev->count == 0)
 		ubd_close_dev(ubd_dev);
 	mutex_unlock(&ubd_mutex);
-	return 0;
 }
 
 static void cowify_bitmap(__u64 io_offset, int length, unsigned long *cow_mask,

arch/xtensa/platforms/iss/simdisk.c

···
 	return 0;
 }
 
-static int simdisk_release(struct gendisk *disk, fmode_t mode)
+static void simdisk_release(struct gendisk *disk, fmode_t mode)
 {
 	struct simdisk *dev = disk->private_data;
 	spin_lock(&dev->lock);
 	--dev->users;
 	spin_unlock(&dev->lock);
-	return 0;
 }
 
 static const struct block_device_operations simdisk_ops = {

drivers/block/amiflop.c

···
 	return 0;
 }
 
-static int floppy_release(struct gendisk *disk, fmode_t mode)
+static void floppy_release(struct gendisk *disk, fmode_t mode)
 {
 	struct amiga_floppy_struct *p = disk->private_data;
 	int drive = p - unit;
···
 	floppy_off (drive | 0x40000000);
 #endif
 	mutex_unlock(&amiflop_mutex);
-	return 0;
 }
 
 /*

drivers/block/aoe/aoeblk.c

···
 	return -ENODEV;
 }
 
-static int
+static void
 aoeblk_release(struct gendisk *disk, fmode_t mode)
 {
 	struct aoedev *d = disk->private_data;
···
 	if (--d->nopen == 0) {
 		spin_unlock_irqrestore(&d->lock, flags);
 		aoecmd_cfg(d->aoemajor, d->aoeminor);
-		return 0;
+		return;
 	}
 	spin_unlock_irqrestore(&d->lock, flags);
-
-	return 0;
 }
 
 static void

drivers/block/ataflop.c

···
 static int fd_test_drive_present( int drive );
 static void config_types( void );
 static int floppy_open(struct block_device *bdev, fmode_t mode);
-static int floppy_release(struct gendisk *disk, fmode_t mode);
+static void floppy_release(struct gendisk *disk, fmode_t mode);
 
 /************************* End of Prototypes **************************/
 
···
 	return ret;
 }
 
-static int floppy_release(struct gendisk *disk, fmode_t mode)
+static void floppy_release(struct gendisk *disk, fmode_t mode)
 {
 	struct atari_floppy_struct *p = disk->private_data;
 	mutex_lock(&ataflop_mutex);
···
 		p->ref = 0;
 	}
 	mutex_unlock(&ataflop_mutex);
-	return 0;
 }
 
 static const struct block_device_operations floppy_fops = {

drivers/block/cciss.c

···
 static irqreturn_t do_cciss_msix_intr(int irq, void *dev_id);
 static int cciss_open(struct block_device *bdev, fmode_t mode);
 static int cciss_unlocked_open(struct block_device *bdev, fmode_t mode);
-static int cciss_release(struct gendisk *disk, fmode_t mode);
+static void cciss_release(struct gendisk *disk, fmode_t mode);
 static int do_ioctl(struct block_device *bdev, fmode_t mode,
 		    unsigned int cmd, unsigned long arg);
 static int cciss_ioctl(struct block_device *bdev, fmode_t mode,
···
 /*
  * Close.  Sync first.
  */
-static int cciss_release(struct gendisk *disk, fmode_t mode)
+static void cciss_release(struct gendisk *disk, fmode_t mode)
 {
 	ctlr_info_t *h;
 	drive_info_struct *drv;
···
 	drv->usage_count--;
 	h->usage_count--;
 	mutex_unlock(&cciss_mutex);
-	return 0;
 }
 
 static int do_ioctl(struct block_device *bdev, fmode_t mode,

drivers/block/cpqarray.c

···
 	unsigned int log_unit );
 
 static int ida_unlocked_open(struct block_device *bdev, fmode_t mode);
-static int ida_release(struct gendisk *disk, fmode_t mode);
+static void ida_release(struct gendisk *disk, fmode_t mode);
 static int ida_ioctl(struct block_device *bdev, fmode_t mode, unsigned int cmd, unsigned long arg);
 static int ida_getgeo(struct block_device *bdev, struct hd_geometry *geo);
 static int ida_ctlr_ioctl(ctlr_info_t *h, int dsk, ida_ioctl_t *io);
···
 /*
  * Close.  Sync first.
  */
-static int ida_release(struct gendisk *disk, fmode_t mode)
+static void ida_release(struct gendisk *disk, fmode_t mode)
 {
 	ctlr_info_t *host;
 
···
 	host = get_host(disk);
 	host->usage_count--;
 	mutex_unlock(&cpqarray_mutex);
-
-	return 0;
 }
 
 /*

drivers/block/drbd/drbd_main.c

···
 
 int drbd_init(void);
 static int drbd_open(struct block_device *bdev, fmode_t mode);
-static int drbd_release(struct gendisk *gd, fmode_t mode);
+static void drbd_release(struct gendisk *gd, fmode_t mode);
 static int w_md_sync(struct drbd_work *w, int unused);
 static void md_sync_timer_fn(unsigned long data);
 static int w_bitmap_io(struct drbd_work *w, int unused);
···
 	return rv;
 }
 
-static int drbd_release(struct gendisk *gd, fmode_t mode)
+static void drbd_release(struct gendisk *gd, fmode_t mode)
 {
 	struct drbd_conf *mdev = gd->private_data;
 	mutex_lock(&drbd_main_mutex);
 	mdev->open_cnt--;
 	mutex_unlock(&drbd_main_mutex);
-	return 0;
 }
 
 static void drbd_set_defaults(struct drbd_conf *mdev)

drivers/block/floppy.c

···
 		pr_cont("\n");
 }
 
-static int floppy_release(struct gendisk *disk, fmode_t mode)
+static void floppy_release(struct gendisk *disk, fmode_t mode)
 {
 	int drive = (long)disk->private_data;
 
···
 		opened_bdev[drive] = NULL;
 	mutex_unlock(&open_lock);
 	mutex_unlock(&floppy_mutex);
-
-	return 0;
 }
 
 /*

drivers/block/loop.c

···
 	return err;
 }
 
-static int lo_release(struct gendisk *disk, fmode_t mode)
+static void lo_release(struct gendisk *disk, fmode_t mode)
 {
 	struct loop_device *lo = disk->private_data;
 	int err;
···
 		 */
 		err = loop_clr_fd(lo);
 		if (!err)
-			goto out_unlocked;
+			return;
 	} else {
 		/*
 		 * Otherwise keep thread (if running) and config,
···
 
 out:
 	mutex_unlock(&lo->lo_ctl_mutex);
-out_unlocked:
-	return 0;
 }
 
 static const struct block_device_operations lo_fops = {

drivers/block/paride/pcd.c

···
 	return ret;
 }
 
-static int pcd_block_release(struct gendisk *disk, fmode_t mode)
+static void pcd_block_release(struct gendisk *disk, fmode_t mode)
 {
 	struct pcd_unit *cd = disk->private_data;
 	mutex_lock(&pcd_mutex);
 	cdrom_release(&cd->info, mode);
 	mutex_unlock(&pcd_mutex);
-	return 0;
 }
 
 static int pcd_block_ioctl(struct block_device *bdev, fmode_t mode,

drivers/block/paride/pd.c

···
 	}
 }
 
-static int pd_release(struct gendisk *p, fmode_t mode)
+static void pd_release(struct gendisk *p, fmode_t mode)
 {
 	struct pd_unit *disk = p->private_data;
 
···
 	if (!--disk->access && disk->removable)
 		pd_special_command(disk, pd_door_unlock);
 	mutex_unlock(&pd_mutex);
-
-	return 0;
 }
 
 static unsigned int pd_check_events(struct gendisk *p, unsigned int clearing)

drivers/block/paride/pf.c

···
 		    unsigned int cmd, unsigned long arg);
 static int pf_getgeo(struct block_device *bdev, struct hd_geometry *geo);
 
-static int pf_release(struct gendisk *disk, fmode_t mode);
+static void pf_release(struct gendisk *disk, fmode_t mode);
 
 static int pf_detect(void);
 static void do_pf_read(void);
···
 	return 0;
 }
 
-static int pf_release(struct gendisk *disk, fmode_t mode)
+static void pf_release(struct gendisk *disk, fmode_t mode)
 {
 	struct pf_unit *pf = disk->private_data;
 
 	mutex_lock(&pf_mutex);
 	if (pf->access <= 0) {
 		mutex_unlock(&pf_mutex);
-		return -EINVAL;
+		WARN_ON(1);
+		return;
 	}
 
 	pf->access--;
···
 		pf_lock(pf, 0);
 
 	mutex_unlock(&pf_mutex);
-	return 0;
-
 }
 
 static unsigned int pf_check_events(struct gendisk *disk, unsigned int clearing)

drivers/block/pktcdvd.c

···
 	return ret;
 }
 
-static int pkt_close(struct gendisk *disk, fmode_t mode)
+static void pkt_close(struct gendisk *disk, fmode_t mode)
 {
 	struct pktcdvd_device *pd = disk->private_data;
-	int ret = 0;
 
 	mutex_lock(&pktcdvd_mutex);
 	mutex_lock(&ctl_mutex);
···
 	}
 	mutex_unlock(&ctl_mutex);
 	mutex_unlock(&pktcdvd_mutex);
-	return ret;
 }
 
 

drivers/block/rbd.c

···
 	return 0;
 }
 
-static int rbd_release(struct gendisk *disk, fmode_t mode)
+static void rbd_release(struct gendisk *disk, fmode_t mode)
 {
 	struct rbd_device *rbd_dev = disk->private_data;
 	unsigned long open_count_before;
···
 	mutex_lock_nested(&ctl_mutex, SINGLE_DEPTH_NESTING);
 	put_device(&rbd_dev->dev);
 	mutex_unlock(&ctl_mutex);
-
-	return 0;
 }
 
 static const struct block_device_operations rbd_bd_ops = {

drivers/block/swim.c

···
 	return ret;
 }
 
-static int floppy_release(struct gendisk *disk, fmode_t mode)
+static void floppy_release(struct gendisk *disk, fmode_t mode)
 {
 	struct floppy_state *fs = disk->private_data;
 	struct swim __iomem *base = fs->swd->base;
···
 	if (fs->ref_count == 0)
 		swim_motor(base, OFF);
 	mutex_unlock(&swim_mutex);
-
-	return 0;
 }
 
 static int floppy_ioctl(struct block_device *bdev, fmode_t mode,

drivers/block/swim3.c

···
 static int floppy_ioctl(struct block_device *bdev, fmode_t mode,
 			unsigned int cmd, unsigned long param);
 static int floppy_open(struct block_device *bdev, fmode_t mode);
-static int floppy_release(struct gendisk *disk, fmode_t mode);
+static void floppy_release(struct gendisk *disk, fmode_t mode);
 static unsigned int floppy_check_events(struct gendisk *disk,
 					unsigned int clearing);
 static int floppy_revalidate(struct gendisk *disk);
···
 	return ret;
 }
 
-static int floppy_release(struct gendisk *disk, fmode_t mode)
+static void floppy_release(struct gendisk *disk, fmode_t mode)
 {
 	struct floppy_state *fs = disk->private_data;
 	struct swim3 __iomem *sw = fs->swim3;
···
 		swim3_select(fs, RELAX);
 	}
 	mutex_unlock(&swim3_mutex);
-	return 0;
 }
 
 static unsigned int floppy_check_events(struct gendisk *disk,

drivers/block/xen-blkfront.c

···
 	return err;
 }
 
-static int blkif_release(struct gendisk *disk, fmode_t mode)
+static void blkif_release(struct gendisk *disk, fmode_t mode)
 {
 	struct blkfront_info *info = disk->private_data;
 	struct block_device *bdev;
···
 out:
 	bdput(bdev);
 	mutex_unlock(&blkfront_mutex);
-	return 0;
 }
 
 static const struct block_device_operations xlvbd_block_fops =

drivers/block/xsysace.c

···
 	return 0;
 }
 
-static int ace_release(struct gendisk *disk, fmode_t mode)
+static void ace_release(struct gendisk *disk, fmode_t mode)
 {
 	struct ace_device *ace = disk->private_data;
 	unsigned long flags;
···
 	}
 	spin_unlock_irqrestore(&ace->lock, flags);
 	mutex_unlock(&xsysace_mutex);
-	return 0;
 }
 
 static int ace_getgeo(struct block_device *bdev, struct hd_geometry *geo)

drivers/block/z2ram.c

···
     return rc;
 }
 
-static int
+static void
 z2_release(struct gendisk *disk, fmode_t mode)
 {
     mutex_lock(&z2ram_mutex);
     if ( current_device == -1 ) {
     	mutex_unlock(&z2ram_mutex);
-    	return 0;
+    	return;
     }
     mutex_unlock(&z2ram_mutex);
     /*
      * FIXME: unmap memory
      */
-
-    return 0;
 }
 
 static const struct block_device_operations z2_fops =

drivers/cdrom/gdrom.c

···
 	return ret;
 }
 
-static int gdrom_bdops_release(struct gendisk *disk, fmode_t mode)
+static void gdrom_bdops_release(struct gendisk *disk, fmode_t mode)
 {
 	mutex_lock(&gdrom_mutex);
 	cdrom_release(gd.cd_info, mode);
 	mutex_unlock(&gdrom_mutex);
-	return 0;
 }
 
 static unsigned int gdrom_bdops_check_events(struct gendisk *disk,

drivers/ide/ide-cd.c

···
 	return rc;
 }
 
-static int idecd_release(struct gendisk *disk, fmode_t mode)
+static void idecd_release(struct gendisk *disk, fmode_t mode)
 {
 	struct cdrom_info *info = ide_drv_g(disk, cdrom_info);
 
···
 
 	ide_cd_put(info);
 	mutex_unlock(&ide_cd_mutex);
-
-	return 0;
 }
 
 static int idecd_set_spindown(struct cdrom_device_info *cdi, unsigned long arg)

drivers/ide/ide-gd.c

···
 }
 
 
-static int ide_gd_release(struct gendisk *disk, fmode_t mode)
+static void ide_gd_release(struct gendisk *disk, fmode_t mode)
 {
 	struct ide_disk_obj *idkp = ide_drv_g(disk, ide_disk_obj);
 	ide_drive_t *drive = idkp->drive;
···
 
 	ide_disk_put(idkp);
 	mutex_unlock(&ide_gd_mutex);
-
-	return 0;
 }
 
 static int ide_gd_getgeo(struct block_device *bdev, struct hd_geometry *geo)

drivers/ide/ide-tape.c

···
 	return 0;
 }
 
-static int idetape_release(struct gendisk *disk, fmode_t mode)
+static void idetape_release(struct gendisk *disk, fmode_t mode)
 {
 	struct ide_tape_obj *tape = ide_drv_g(disk, ide_tape_obj);
 
 	mutex_lock(&ide_tape_mutex);
 	ide_tape_put(tape);
 	mutex_unlock(&ide_tape_mutex);
-
-	return 0;
 }
 
 static int idetape_ioctl(struct block_device *bdev, fmode_t mode,

drivers/md/dm.c

···
 	return md ? 0 : -ENXIO;
 }
 
-static int dm_blk_close(struct gendisk *disk, fmode_t mode)
+static void dm_blk_close(struct gendisk *disk, fmode_t mode)
 {
 	struct mapped_device *md = disk->private_data;
 
···
 	dm_put(md);
 
 	spin_unlock(&_minor_lock);
-
-	return 0;
 }
 
 int dm_open_count(struct mapped_device *md)

drivers/md/md.c

···
 	return err;
 }
 
-static int md_release(struct gendisk *disk, fmode_t mode)
+static void md_release(struct gendisk *disk, fmode_t mode)
 {
  	struct mddev *mddev = disk->private_data;
 
 	BUG_ON(!mddev);
 	atomic_dec(&mddev->openers);
 	mddev_put(mddev);
-
-	return 0;
 }
 
 static int md_media_changed(struct gendisk *disk)

drivers/memstick/core/mspro_block.c

···
 }
 
 
-static int mspro_block_disk_release(struct gendisk *disk)
+static void mspro_block_disk_release(struct gendisk *disk)
 {
 	struct mspro_block_data *msb = disk->private_data;
 	int disk_id = MINOR(disk_devt(disk)) >> MSPRO_BLOCK_PART_SHIFT;
···
 	}
 
 	mutex_unlock(&mspro_block_disk_lock);
-
-	return 0;
 }
 
-static int mspro_block_bd_release(struct gendisk *disk, fmode_t mode)
+static void mspro_block_bd_release(struct gendisk *disk, fmode_t mode)
 {
-	return mspro_block_disk_release(disk);
+	mspro_block_disk_release(disk);
 }
 
 static int mspro_block_bd_getgeo(struct block_device *bdev,

drivers/message/i2o/i2o_block.c

···
  *
  *	Unlock and unmount the media, and power down the device. Gets called if
  *	the block device is closed.
- *
- *	Returns 0 on success or negative error code on failure.
  */
-static int i2o_block_release(struct gendisk *disk, fmode_t mode)
+static void i2o_block_release(struct gendisk *disk, fmode_t mode)
 {
 	struct i2o_block_device *dev = disk->private_data;
 	u8 operation;
···
 	 * the TID no longer exists.
 	 */
 	if (!dev->i2o_dev)
-		return 0;
+		return;
 
 	mutex_lock(&i2o_block_mutex);
 	i2o_block_device_flush(dev->i2o_dev);
···
 
 	i2o_block_device_power(dev, operation);
 	mutex_unlock(&i2o_block_mutex);
-
-	return 0;
 }
 
 static int i2o_block_getgeo(struct block_device *bdev, struct hd_geometry *geo)

drivers/mmc/card/block.c

···
 	return ret;
 }
 
-static int mmc_blk_release(struct gendisk *disk, fmode_t mode)
+static void mmc_blk_release(struct gendisk *disk, fmode_t mode)
 {
 	struct mmc_blk_data *md = disk->private_data;
 
 	mutex_lock(&block_mutex);
 	mmc_blk_put(md);
 	mutex_unlock(&block_mutex);
-	return 0;
 }
 
 static int

drivers/mtd/mtd_blkdevs.c

···
 	return ret;
 }
 
-static int blktrans_release(struct gendisk *disk, fmode_t mode)
+static void blktrans_release(struct gendisk *disk, fmode_t mode)
 {
 	struct mtd_blktrans_dev *dev = blktrans_dev_get(disk);
 
 	if (!dev)
-		return 0;
+		return;
 
 	mutex_lock(&dev->lock);
 
···
 unlock:
 	mutex_unlock(&dev->lock);
 	blktrans_dev_put(dev);
-	return 0;
 }
 
 static int blktrans_getgeo(struct block_device *bdev, struct hd_geometry *geo)

drivers/s390/block/dasd.c

···
 	return rc;
 }
 
-static int dasd_release(struct gendisk *disk, fmode_t mode)
+static void dasd_release(struct gendisk *disk, fmode_t mode)
 {
-	struct dasd_device *base;
-
-	base = dasd_device_from_gendisk(disk);
-	if (!base)
-		return -ENODEV;
-
-	atomic_dec(&base->block->open_count);
-	module_put(base->discipline->owner);
-	dasd_put_device(base);
-	return 0;
+	struct dasd_device *base = dasd_device_from_gendisk(disk);
+	if (base) {
+		atomic_dec(&base->block->open_count);
+		module_put(base->discipline->owner);
+		dasd_put_device(base);
+	}
 }
 
 /*

drivers/s390/block/dcssblk.c

···
 #define DCSS_BUS_ID_SIZE 20
 
 static int dcssblk_open(struct block_device *bdev, fmode_t mode);
-static int dcssblk_release(struct gendisk *disk, fmode_t mode);
+static void dcssblk_release(struct gendisk *disk, fmode_t mode);
 static void dcssblk_make_request(struct request_queue *q, struct bio *bio);
 static int dcssblk_direct_access(struct block_device *bdev, sector_t secnum,
 				 void **kaddr, unsigned long *pfn);
···
 	return rc;
 }
 
-static int
+static void
 dcssblk_release(struct gendisk *disk, fmode_t mode)
 {
 	struct dcssblk_dev_info *dev_info = disk->private_data;
 	struct segment_info *entry;
-	int rc;
 
 	if (!dev_info) {
-		rc = -ENODEV;
-		goto out;
+		WARN_ON(1);
+		return;
 	}
 	down_write(&dcssblk_devices_sem);
 	if (atomic_dec_and_test(&dev_info->use_count)
···
 		dev_info->save_pending = 0;
 	}
 	up_write(&dcssblk_devices_sem);
-	rc = 0;
-out:
-	return rc;
 }
 
 static void

drivers/s390/block/scm_blk.c

···
 	return scm_get_ref();
 }
 
-static int scm_release(struct gendisk *gendisk, fmode_t mode)
+static void scm_release(struct gendisk *gendisk, fmode_t mode)
 {
 	scm_put_ref();
-	return 0;
 }
 
 static const struct block_device_operations scm_blk_devops = {

drivers/scsi/sd.c

···
  *
  *	Locking: called with bdev->bd_mutex held.
  **/
-static int sd_release(struct gendisk *disk, fmode_t mode)
+static void sd_release(struct gendisk *disk, fmode_t mode)
 {
 	struct scsi_disk *sdkp = scsi_disk(disk);
 	struct scsi_device *sdev = sdkp->device;
···
 
 	scsi_autopm_put_device(sdev);
 	scsi_disk_put(sdkp);
-	return 0;
 }
 
 static int sd_getgeo(struct block_device *bdev, struct hd_geometry *geo)

drivers/scsi/sr.c

···
 	return ret;
 }
 
-static int sr_block_release(struct gendisk *disk, fmode_t mode)
+static void sr_block_release(struct gendisk *disk, fmode_t mode)
 {
 	struct scsi_cd *cd = scsi_cd(disk);
 	mutex_lock(&sr_mutex);
 	cdrom_release(&cd->cdi, mode);
 	scsi_cd_put(cd);
 	mutex_unlock(&sr_mutex);
-	return 0;
 }
 
 static int sr_block_ioctl(struct block_device *bdev, fmode_t mode, unsigned cmd,

fs/block_dev.c

···
 	}
 	if (bdev->bd_contains == bdev) {
 		if (disk->fops->release)
-			ret = disk->fops->release(disk, mode);
+			disk->fops->release(disk, mode);
 	}
 	if (!bdev->bd_openers) {
 		struct module *owner = disk->fops->owner;

include/linux/blkdev.h

···
 
 struct block_device_operations {
 	int (*open) (struct block_device *, fmode_t);
-	int (*release) (struct gendisk *, fmode_t);
+	void (*release) (struct gendisk *, fmode_t);
 	int (*ioctl) (struct block_device *, fmode_t, unsigned, unsigned long);
 	int (*compat_ioctl) (struct block_device *, fmode_t, unsigned, unsigned long);
 	int (*direct_access) (struct block_device *, sector_t,