Newly created block group should reside on empty zones, whose write pointer should always be 0. Also, we can load the zone capacity from the block layer. So, we don't need to REPORT_ZONE to load the info. The reporting zone on a new block group is not only unnecessary, but also can cause a deadlock. When one process do a report zones and another process freezes the block device, the report zones side cannot allocate a tag because the freeze is already started. This can thus result in new block group creation to hang forever, blocking the write path. Naohiro Aota (2): block: introduce zone capacity helper btrfs: zoned: skip reporting zone for new block group fs/btrfs/zoned.c | 18 ++++++++++++++++-- include/linux/blkdev.h | 21 +++++++++++++++++++++ 2 files changed, 37 insertions(+), 2 deletions(-) -- 2.48.1
