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  1. 21 1月, 2021 3 次提交
  3. 15 1月, 2021 12 次提交
  5. 14 1月, 2021 12 次提交
  7. 13 1月, 2021 3 次提交
  9. 12 1月, 2021 4 次提交
  11. 11 1月, 2021 4 次提交
  13. 10 1月, 2021 2 次提交
    • C
      bcache: set bcache device into read-only mode for BCH_FEATURE_INCOMPAT_OBSO_LARGE_BUCKET · 5342fd42
      由 Coly Li 提交于 
      If BCH_FEATURE_INCOMPAT_OBSO_LARGE_BUCKET is set in incompat feature
set, it means the cache device is created with obsoleted layout with
obso_bucket_site_hi. Now bcache does not support this feature bit, a new
BCH_FEATURE_INCOMPAT_LOG_LARGE_BUCKET_SIZE incompat feature bit is added
for a better layout to support large bucket size.

For the legacy compatibility purpose, if a cache device created with
obsoleted BCH_FEATURE_INCOMPAT_OBSO_LARGE_BUCKET feature bit, all bcache
devices attached to this cache set should be set to read-only. Then the
dirty data can be written back to backing device before re-create the
cache device with BCH_FEATURE_INCOMPAT_LOG_LARGE_BUCKET_SIZE feature bit
by the latest bcache-tools.

This patch checks BCH_FEATURE_INCOMPAT_OBSO_LARGE_BUCKET feature bit
when running a cache set and attach a bcache device to the cache set. If
this bit is set,
- When run a cache set, print an error kernel message to indicate all
  following attached bcache device will be read-only.
- When attach a bcache device, print an error kernel message to indicate
  the attached bcache device will be read-only, and ask users to update
  to latest bcache-tools.

Such change is only for cache device whose bucket size >= 32MB, this is
for the zoned SSD and almost nobody uses such large bucket size at this
moment. If you don't explicit set a large bucket size for a zoned SSD,
such change is totally transparent to your bcache device.

Fixes: ffa47032 ("bcache: add bucket_size_hi into struct cache_sb_disk for large bucket")
Signed-off-by: NColy Li <colyli@suse.de>
Signed-off-by: NJens Axboe <axboe@kernel.dk>
      5342fd42
    • C
      bcache: introduce BCH_FEATURE_INCOMPAT_LOG_LARGE_BUCKET_SIZE for large bucket · b16671e8
      由 Coly Li 提交于 
      When large bucket feature was added, BCH_FEATURE_INCOMPAT_LARGE_BUCKET
was introduced into the incompat feature set. It used bucket_size_hi
(which was added at the tail of struct cache_sb_disk) to extend current
16bit bucket size to 32bit with existing bucket_size in struct
cache_sb_disk.

This is not a good idea, there are two obvious problems,
- Bucket size is always value power of 2, if store log2(bucket size) in
  existing bucket_size of struct cache_sb_disk, it is unnecessary to add
  bucket_size_hi.
- Macro csum_set() assumes d[SB_JOURNAL_BUCKETS] is the last member in
  struct cache_sb_disk, bucket_size_hi was added after d[] which makes
  csum_set calculate an unexpected super block checksum.

To fix the above problems, this patch introduces a new incompat feature
bit BCH_FEATURE_INCOMPAT_LOG_LARGE_BUCKET_SIZE, when this bit is set, it
means bucket_size in struct cache_sb_disk stores the order of power-of-2
bucket size value. When user specifies a bucket size larger than 32768
sectors, BCH_FEATURE_INCOMPAT_LOG_LARGE_BUCKET_SIZE will be set to
incompat feature set, and bucket_size stores log2(bucket size) more
than store the real bucket size value.

The obsoleted BCH_FEATURE_INCOMPAT_LARGE_BUCKET won't be used anymore,
it is renamed to BCH_FEATURE_INCOMPAT_OBSO_LARGE_BUCKET and still only
recognized by kernel driver for legacy compatible purpose. The previous
bucket_size_hi is renmaed to obso_bucket_size_hi in struct cache_sb_disk
and not used in bcache-tools anymore.

For cache device created with BCH_FEATURE_INCOMPAT_LARGE_BUCKET feature,
bcache-tools and kernel driver still recognize the feature string and
display it as "obso_large_bucket".

With this change, the unnecessary extra space extend of bcache on-disk
super block can be avoided, and csum_set() may generate expected check
sum as well.

Fixes: ffa47032 ("bcache: add bucket_size_hi into struct cache_sb_disk for large bucket")
Signed-off-by: NColy Li <colyli@suse.de>
Cc: stable@vger.kernel.org # 5.9+
Signed-off-by: NJens Axboe <axboe@kernel.dk>
      b16671e8