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Fix superblock overwriting data blocks with smaller block sizes
+16
-3
+14
-1
lib/xks/free_list.ex
+14
-1
lib/xks/free_list.ex
···
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@spec new(keyword) :: t
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def new(opts) do
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block_size = Keyword.fetch!(opts, :block_size)
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# TODO: constant or configurable?
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superblock_copies = 4
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# This is the number of blocks reserved up-front to hold the superblock copies
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# These blocks will never be reserved and therefore never freed
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superblock_reserved_blocks = ceil((c_superblock_size() * superblock_copies) / block_size)
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assert superblock_reserved_blocks >= 1
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extent_block_count = Keyword.fetch!(opts, :extent_block_count)
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assert is_integer(extent_block_count)
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assert extent_block_count >= 1
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table = :ets.new(__MODULE__, [:ordered_set, :public])
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:ets.insert(table, {:max_block, 0})
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# Set max_block to ensure that superblock space is never reserved
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# -1 here because the first block allocated will be (max_block + 1)
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max_block = superblock_reserved_blocks - 1
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assert max_block >= 0
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:ets.insert(table, {:max_block, max_block})
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:ets.insert(table, {:extent_block_count, extent_block_count})
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table
+2
-2
lib/xks/xks.ex
+2
-2
lib/xks/xks.ex
···
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opts: opts,
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block_store: block_store,
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free_list: FreeList.new(extent_block_count: opts.extent_block_count),
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free_list: FreeList.new(block_size: opts.block_size, extent_block_count: opts.extent_block_count),
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manifest: Manifest.new(),
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manifest_log: ManifestLog.new(),
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work_queue: WorkQueue.new(),
···
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opts: opts,
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block_store: block_store,
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free_list: FreeList.new(extent_block_count: opts.extent_block_count),
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free_list: FreeList.new(block_size: opts.block_size, extent_block_count: opts.extent_block_count),
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manifest: Manifest.new(),
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manifest_log: ManifestLog.new(),
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work_queue: WorkQueue.new(),