Merge tag 'for-linus-20181026' of git://git.kernel.dk/linux-block

Pull more block layer updates from Jens Axboe:

 - Set of patches improving support for zoned devices. This was ready
   before the merge window, but I was late in picking it up and hence it
   missed the original pull request (Damien, Christoph)

 - libata no link power management quirk addition for a Samsung drive
   (Diego Viola)

 - Fix for a performance regression in BFQ that went into this merge
   window (Federico Motta)

 - Fix for a missing dma mask setting return value check (Gustavo)

 - Typo in the gdrom queue failure case (me)

 - NULL pointer deref fix for xen-blkfront (Vasilis Liaskovitis)

 - Fixing the get_rq trace point placement in blk-mq (Xiaoguang Wang)

 - Removal of a set-but-not-read variable in cdrom (zhong jiang)

* tag 'for-linus-20181026' of git://git.kernel.dk/linux-block:
  libata: Apply NOLPM quirk for SAMSUNG MZ7TD256HAFV-000L9
  block, bfq: fix asymmetric scenarios detection
  gdrom: fix mistake in assignment of error
  blk-mq: place trace_block_getrq() in correct place
  block: Introduce blk_revalidate_disk_zones()
  block: add a report_zones method
  block: Expose queue nr_zones in sysfs
  block: Improve zone reset execution
  block: Introduce BLKGETNRZONES ioctl
  block: Introduce BLKGETZONESZ ioctl
  block: Limit allocation of zone descriptors for report zones
  block: Introduce blkdev_nr_zones() helper
  scsi: sd_zbc: Fix sd_zbc_check_zones() error checks
  scsi: sd_zbc: Reduce boot device scan and revalidate time
  scsi: sd_zbc: Rearrange code
  cdrom: remove set but not used variable 'tocuse'
  skd: fix unchecked return values
  xen/blkfront: avoid NULL blkfront_info dereference on device removal

1 files changed, 15 insertions, 42 deletions

diff --git a/drivers/block/null_blk_zoned.c b/drivers/block/null_blk_zoned.c
index 7c6b86d98700..c0b0e4a3fa8f 100644
--- a/drivers/block/null_blk_zoned.c
+++ b/drivers/block/null_blk_zoned.c
@@ -48,54 +48,27 @@ void null_zone_exit(struct nullb_device *dev)
 	kvfree(dev->zones);
 }
 
-static void null_zone_fill_bio(struct nullb_device *dev, struct bio *bio,
-			       unsigned int zno, unsigned int nr_zones)
+int null_zone_report(struct gendisk *disk, sector_t sector,
+		     struct blk_zone *zones, unsigned int *nr_zones,
+		     gfp_t gfp_mask)
 {
-	struct blk_zone_report_hdr *hdr = NULL;
-	struct bio_vec bvec;
-	struct bvec_iter iter;
-	void *addr;
-	unsigned int zones_to_cpy;
-
-	bio_for_each_segment(bvec, bio, iter) {
-		addr = kmap_atomic(bvec.bv_page);
-
-		zones_to_cpy = bvec.bv_len / sizeof(struct blk_zone);
-
-		if (!hdr) {
-			hdr = (struct blk_zone_report_hdr *)addr;
-			hdr->nr_zones = nr_zones;
-			zones_to_cpy--;
-			addr += sizeof(struct blk_zone_report_hdr);
-		}
-
-		zones_to_cpy = min_t(unsigned int, zones_to_cpy, nr_zones);
-
-		memcpy(addr, &dev->zones[zno],
-				zones_to_cpy * sizeof(struct blk_zone));
-
-		kunmap_atomic(addr);
+	struct nullb *nullb = disk->private_data;
+	struct nullb_device *dev = nullb->dev;
+	unsigned int zno, nrz = 0;
 
-		nr_zones -= zones_to_cpy;
-		zno += zones_to_cpy;
+	if (!dev->zoned)
+		/* Not a zoned null device */
+		return -EOPNOTSUPP;
 
-		if (!nr_zones)
-			break;
+	zno = null_zone_no(dev, sector);
+	if (zno < dev->nr_zones) {
+		nrz = min_t(unsigned int, *nr_zones, dev->nr_zones - zno);
+		memcpy(zones, &dev->zones[zno], nrz * sizeof(struct blk_zone));
 	}
-}
 
-blk_status_t null_zone_report(struct nullb *nullb, struct bio *bio)
-{
-	struct nullb_device *dev = nullb->dev;
-	unsigned int zno = null_zone_no(dev, bio->bi_iter.bi_sector);
-	unsigned int nr_zones = dev->nr_zones - zno;
-	unsigned int max_zones;
+	*nr_zones = nrz;
 
-	max_zones = (bio->bi_iter.bi_size / sizeof(struct blk_zone)) - 1;
-	nr_zones = min_t(unsigned int, nr_zones, max_zones);
-	null_zone_fill_bio(nullb->dev, bio, zno, nr_zones);
-
-	return BLK_STS_OK;
+	return 0;
 }
 
 void null_zone_write(struct nullb_cmd *cmd, sector_t sector,