Merge tag 'for-5.15/block-2021-08-30' of git://git.kernel.dk/linux-block

Pull block updates from Jens Axboe:
 "Nothing major in here - lots of good cleanups and tech debt handling,
  which is also evident in the diffstats. In particular:

   - Add disk sequence numbers (Matteo)

   - Discard merge fix (Ming)

   - Relax disk zoned reporting restrictions (Niklas)

   - Bio error handling zoned leak fix (Pavel)

   - Start of proper add_disk() error handling (Luis, Christoph)

   - blk crypto fix (Eric)

   - Non-standard GPT location support (Dmitry)

   - IO priority improvements and cleanups (Damien)o

   - blk-throtl improvements (Chunguang)

   - diskstats_show() stack reduction (Abd-Alrhman)

   - Loop scheduler selection (Bart)

   - Switch block layer to use kmap_local_page() (Christoph)

   - Remove obsolete disk_name helper (Christoph)

   - block_device refcounting improvements (Christoph)

   - Ensure gendisk always has a request queue reference (Christoph)

   - Misc fixes/cleanups (Shaokun, Oliver, Guoqing)"

* tag 'for-5.15/block-2021-08-30' of git://git.kernel.dk/linux-block: (129 commits)
  sg: pass the device name to blk_trace_setup
  block, bfq: cleanup the repeated declaration
  blk-crypto: fix check for too-large dun_bytes
  blk-zoned: allow BLKREPORTZONE without CAP_SYS_ADMIN
  blk-zoned: allow zone management send operations without CAP_SYS_ADMIN
  block: mark blkdev_fsync static
  block: refine the disk_live check in del_gendisk
  mmc: sdhci-tegra: Enable MMC_CAP2_ALT_GPT_TEGRA
  mmc: block: Support alternative_gpt_sector() operation
  partitions/efi: Support non-standard GPT location
  block: Add alternative_gpt_sector() operation
  bio: fix page leak bio_add_hw_page failure
  block: remove CONFIG_DEBUG_BLOCK_EXT_DEVT
  block: remove a pointless call to MINOR() in device_add_disk
  null_blk: add error handling support for add_disk()
  virtio_blk: add error handling support for add_disk()
  block: add error handling for device_add_disk / add_disk
  block: return errors from disk_alloc_events
  block: return errors from blk_integrity_add
  block: call blk_register_queue earlier in device_add_disk
  ...

1 files changed, 9 insertions, 14 deletions

diff --git a/block/blk-iocost.c b/block/blk-iocost.c
index 0e56557cacf2..b3880e4ba22a 100644
--- a/block/blk-iocost.c
+++ b/block/blk-iocost.c
@@ -2988,34 +2988,29 @@ static void ioc_pd_free(struct blkg_policy_data *pd)
 	kfree(iocg);
 }
 
-static size_t ioc_pd_stat(struct blkg_policy_data *pd, char *buf, size_t size)
+static bool ioc_pd_stat(struct blkg_policy_data *pd, struct seq_file *s)
 {
 	struct ioc_gq *iocg = pd_to_iocg(pd);
 	struct ioc *ioc = iocg->ioc;
-	size_t pos = 0;
 
 	if (!ioc->enabled)
-		return 0;
+		return false;
 
 	if (iocg->level == 0) {
 		unsigned vp10k = DIV64_U64_ROUND_CLOSEST(
 			ioc->vtime_base_rate * 10000,
 			VTIME_PER_USEC);
-		pos += scnprintf(buf + pos, size - pos, " cost.vrate=%u.%02u",
-				  vp10k / 100, vp10k % 100);
+		seq_printf(s, " cost.vrate=%u.%02u", vp10k / 100, vp10k % 100);
 	}
 
-	pos += scnprintf(buf + pos, size - pos, " cost.usage=%llu",
-			 iocg->last_stat.usage_us);
+	seq_printf(s, " cost.usage=%llu", iocg->last_stat.usage_us);
 
 	if (blkcg_debug_stats)
-		pos += scnprintf(buf + pos, size - pos,
-				 " cost.wait=%llu cost.indebt=%llu cost.indelay=%llu",
-				 iocg->last_stat.wait_us,
-				 iocg->last_stat.indebt_us,
-				 iocg->last_stat.indelay_us);
-
-	return pos;
+		seq_printf(s, " cost.wait=%llu cost.indebt=%llu cost.indelay=%llu",
+			iocg->last_stat.wait_us,
+			iocg->last_stat.indebt_us,
+			iocg->last_stat.indelay_us);
+	return true;
 }
 
 static u64 ioc_weight_prfill(struct seq_file *sf, struct blkg_policy_data *pd,