Josef Bacik cbbfdb4bab btrfs: properly report 0 avail for very full file systems
commit 58bfe2ccec5f9f137b41dd38f335290dcc13cd5c upstream.

A user reported some issues with smaller file systems that get very
full.  While investigating this issue I noticed that df wasn't showing
100% full, despite having 0 chunk space and having < 1MiB of available
metadata space.

This turns out to be an overflow issue, we're doing:

  total_available_metadata_space - SZ_4M < global_block_rsv_size

to determine if there's not enough space to make metadata allocations,
which overflows if total_available_metadata_space is < 4M.  Fix this by
checking to see if our available space is greater than the 4M threshold.
This makes df properly report 100% usage on the file system.

CC: stable@vger.kernel.org # 4.14+
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-10-10 21:53:35 +02:00
..
2023-06-21 15:45:40 +02:00
2021-09-18 13:40:15 +02:00
2023-05-17 11:47:35 +02:00
2023-09-19 12:20:23 +02:00
2023-02-22 12:55:54 +01:00
2023-09-23 11:01:09 +02:00
2022-06-09 10:21:16 +02:00
2023-01-04 11:39:23 +01:00
2023-01-14 10:16:27 +01:00