block: Modify revalidate zones

Modify the interface of blk_revalidate_disk_zones() to add an optional
driver callback function that a driver can use to extend processing
done during zone revalidation. The callback, if defined, is executed
with the device request queue frozen, after all zones have been
inspected.

Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com>
Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

diff --git a/block/blk-zoned.c b/block/blk-zoned.c
index c822cfa..23831fa 100644 (file)
--- a/block/blk-zoned.c
+++ b/block/blk-zoned.c
@@ -471,14 +471,19 @@ static int blk_revalidate_zone_cb(struct blk_zone *zone, unsigned int idx,
 /**
  * blk_revalidate_disk_zones - (re)allocate and initialize zone bitmaps
  * @disk:      Target disk
+ * @update_driver_data:        Callback to update driver data on the frozen disk
  *
  * 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 blk-mq based drivers.  For BIO based
  * drivers only q->nr_zones needs to be updated so that the sysfs exposed value
  * is correct.
+ * If the @update_driver_data callback function is not NULL, the callback is
+ * executed with the device request queue frozen after all zones have been
+ * checked.
  */
-int blk_revalidate_disk_zones(struct gendisk *disk)
+int blk_revalidate_disk_zones(struct gendisk *disk,
+                             void (*update_driver_data)(struct gendisk *disk))
 {
        struct request_queue *q = disk->queue;
        struct blk_revalidate_zone_args args = {
@@ -512,6 +517,8 @@ int blk_revalidate_disk_zones(struct gendisk *disk)
                q->nr_zones = args.nr_zones;
                swap(q->seq_zones_wlock, args.seq_zones_wlock);
                swap(q->conv_zones_bitmap, args.conv_zones_bitmap);
+               if (update_driver_data)
+                       update_driver_data(disk);
                ret = 0;
        } else {
                pr_warn("%s: failed to revalidate zones\n", disk->disk_name);

diff --git a/drivers/block/null_blk_zoned.c b/drivers/block/null_blk_zoned.c
index 9e4bcda..46641df 100644 (file)
--- a/drivers/block/null_blk_zoned.c
+++ b/drivers/block/null_blk_zoned.c
@@ -73,7 +73,7 @@ int null_register_zoned_dev(struct nullb *nullb)
        struct request_queue *q = nullb->q;
 
        if (queue_is_mq(q))
-               return blk_revalidate_disk_zones(nullb->disk);
+               return blk_revalidate_disk_zones(nullb->disk, NULL);
 
        blk_queue_chunk_sectors(q, nullb->dev->zone_size_sects);
        q->nr_zones = blkdev_nr_zones(nullb->disk);

diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h
index 73f4f4f..5360696 100644 (file)
--- a/include/linux/blkdev.h
+++ b/include/linux/blkdev.h
@@ -358,7 +358,8 @@ unsigned int blkdev_nr_zones(struct gendisk *disk);
 extern int blkdev_zone_mgmt(struct block_device *bdev, enum req_opf op,
                            sector_t sectors, sector_t nr_sectors,
                            gfp_t gfp_mask);
-extern int blk_revalidate_disk_zones(struct gendisk *disk);
+int blk_revalidate_disk_zones(struct gendisk *disk,
+                             void (*update_driver_data)(struct gendisk *disk));
 
 extern int blkdev_report_zones_ioctl(struct block_device *bdev, fmode_t mode,
                                     unsigned int cmd, unsigned long arg);