block: don't handle bio based drivers in blk_revalidate_disk_zones

bio based drivers only need to update q->nr_zones.  Do that manually
instead of overloading blk_revalidate_disk_zones to keep that function
simpler for the next round of changes that will rely even more on the
request based functionality.

Reviewed-by: Javier González <javier@javigon.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

diff --git a/block/blk-zoned.c b/block/blk-zoned.c
index 0131f9e..51d4276 100644 (file)
--- a/block/blk-zoned.c
+++ b/block/blk-zoned.c
@@ -419,8 +419,9 @@ static int blk_revalidate_zone_cb(struct blk_zone *zone, unsigned int idx,
  *
  * Helper function for low-level device drivers to (re) allocate and initialize
  * a disk request queue zone bitmaps. This functions should normally be called
- * within the disk ->revalidate method. For BIO based queues, no zone bitmap
- * is allocated.
+ * within the disk ->revalidate method for blk-mq based drivers.  For BIO based
+ * drivers only q->nr_zones needs to be updated so that the sysfs exposed value
+ * is correct.
  */
 int blk_revalidate_disk_zones(struct gendisk *disk)
 {
@@ -433,15 +434,8 @@ int blk_revalidate_disk_zones(struct gendisk *disk)
 
        if (WARN_ON_ONCE(!blk_queue_is_zoned(q)))
                return -EIO;
-
-       /*
-        * BIO based queues do not use a scheduler so only q->nr_zones
-        * needs to be updated so that the sysfs exposed value is correct.
-        */
-       if (!queue_is_mq(q)) {
-               q->nr_zones = args.nr_zones;
-               return 0;
-       }
+       if (WARN_ON_ONCE(!queue_is_mq(q)))
+               return -EIO;
 
        /*
         * Ensure that all memory allocations in this context are done as

diff --git a/drivers/block/null_blk_main.c b/drivers/block/null_blk_main.c
index dd60262..068cd0a 100644 (file)
--- a/drivers/block/null_blk_main.c
+++ b/drivers/block/null_blk_main.c
@@ -1576,11 +1576,17 @@ static int null_gendisk_register(struct nullb *nullb)
        disk->queue             = nullb->q;
        strncpy(disk->disk_name, nullb->disk_name, DISK_NAME_LEN);
 
+#ifdef CONFIG_BLK_DEV_ZONED
        if (nullb->dev->zoned) {
-               ret = blk_revalidate_disk_zones(disk);
-               if (ret)
-                       return ret;
+               if (queue_is_mq(nullb->q)) {
+                       ret = blk_revalidate_disk_zones(disk);
+                       if (ret)
+                               return ret;
+               } else {
+                       nullb->q->nr_zones = blkdev_nr_zones(disk);
+               }
        }
+#endif
 
        add_disk(disk);
        return 0;

diff --git a/drivers/md/dm-table.c b/drivers/md/dm-table.c
index 2ae0c19..0a2cc19 100644 (file)
--- a/drivers/md/dm-table.c
+++ b/drivers/md/dm-table.c
@@ -1954,12 +1954,14 @@ void dm_table_set_restrictions(struct dm_table *t, struct request_queue *q,
        /*
         * For a zoned target, the number of zones should be updated for the
         * correct value to be exposed in sysfs queue/nr_zones. For a BIO based
-        * target, this is all that is needed. For a request based target, the
-        * queue zone bitmaps must also be updated.
-        * Use blk_revalidate_disk_zones() to handle this.
+        * target, this is all that is needed.
         */
-       if (blk_queue_is_zoned(q))
-               blk_revalidate_disk_zones(t->md->disk);
+#ifdef CONFIG_BLK_DEV_ZONED
+       if (blk_queue_is_zoned(q)) {
+               WARN_ON_ONCE(queue_is_mq(q));
+               q->nr_zones = blkdev_nr_zones(t->md->disk);
+       }
+#endif
 
        /* Allow reads to exceed readahead limits */
        q->backing_dev_info->io_pages = limits->max_sectors >> (PAGE_SHIFT - 9);

diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h
index 503c4d4..47eb22a 100644 (file)
--- a/include/linux/blkdev.h
+++ b/include/linux/blkdev.h
@@ -375,11 +375,6 @@ static inline unsigned int blkdev_nr_zones(struct gendisk *disk)
        return 0;
 }
 
-static inline int blk_revalidate_disk_zones(struct gendisk *disk)
-{
-       return 0;
-}
-
 static inline int blkdev_report_zones_ioctl(struct block_device *bdev,
                                            fmode_t mode, unsigned int cmd,
                                            unsigned long arg)